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Nathan Goodyear

Adipose Tissue Inflammation in Obesity and Metabolic Syndrome - - Satoshi Nishimura - D... - 0 views

www.discoverymedicine.com/...obesity-and-metabolic-syndrome

inflammation obesity metabolic syndrome fat adipose tissue innate immune system humoral

shared by Nathan Goodyear on 21 Dec 11 - No Cached
  • Activation of inflammatory pathways in adipocytes impairs triglyceride storage and increases release of free fatty acids, an excess of which is known to induce insulin resistance in muscle and liver
  • recent studies have shown that large numbers of macrophages infiltrate obese adipose tissue,
  • It has been postulated that a paracrine loop involving free fatty acids and inflammatory cytokines establishes a vicious cycle between adipocytes and macrophages that propagates the inflammation
  • ...5 more annotations...
  • not only does interrupting the accumulation of macrophages within obese adipose tissue suppresses adipose inflammation in various animal models, it also ameliorates systemic insulin resistance and metabolic abnormalities, suggesting macrophages are key effector cells involved in adipose inflammation
  • activation of the leukocyte adhesion cascade, a hallmark of inflammation
  • Thus, obese visceral adipose tissue is clearly a site of chronic inflammation
  • CD8+ T cells within obese adipose tissue induce activation and migration of monocytes/macrophages, and in cooperation with the adipose tissue, they also induce macrophage differentiation. At the same time, obese adipose tissue activates CD8+ T cells, creating a vicious cycle involving CD8+ T cells, macrophages, and obese adipose tissue that propagates local inflammation
  • In obese adipose tissue there is a shift to dominance of CD8+ and TH1 T cells, which appears to propagate inflammation
  • Nathan Goodyear on 21 Dec 11
     
    fascinating read how the immune system and resultant inflammation results in obesity.
Nathan Goodyear

Adipose tissue macrophages: p... [Curr Opin Clin Nutr Metab Care. 2011] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...21587064

adipose tissue macrophages ATMs adipose tissue obesity M2 M1 macrophages

shared by Nathan Goodyear on 04 Jan 13 - No Cached
  • Nathan Goodyear on 04 Jan 13
     
    adipose tissue changes the macrophage type from M2 to M1 dominance.  This reveals the microenvironment found in adipose tissue and the effect on the adipose tissue macrophages.
Nathan Goodyear

The 4-Pregnene and 5α-Pregnane Progesterone Metabolites Formed in Nontumorous... - 0 views

cancerres.aacrjournals.org/...936.full

progesterone metabolism cancer risk 4-pregnene 5alpha-pregnane

shared by Nathan Goodyear on 17 Feb 12 - No Cached
  • We report here the first evidence that tumorous breast tissue exhibits elevated 5α-reductase activity, which promotes significant increases in 5α-pregnanes, especially 5αP,4 whereas the normal (nontumorous) breast tissue produces more 4-pregnenes, especially 3αHP
  • 3αHP and other 4-pregnenes inhibit, whereas 5αP and other 5α-pregnanes stimulate, breast cell proliferation and detachment
  • it is evident that breast tissue can convert progesterone into two classes of metabolites: the δ-4-pregnenes (which retain the C4–5 double bond), and the 5α-reduced 21-carbon steroids (5α-pregnanes)
  • ...12 more annotations...
  • irreversible action of 5α-reductase
  • in normal (nontumorous) breast tissue, the 4-pregnene metabolites of progesterone greatly exceeded the 5α-pregnanes, whereas in tumorous tissue, 5α-pregnanes exceeded 4-pregnenes.
  • These differences in 5α-pregnane and 4-pregnene amounts were largely attributable to differences in 5αP and 3αHP production in tumorous and nontumorous tissues
  • the metabolic activities were in general similar, regardless of the age and ER state of the patient or whether she was pre- or postmenopausal.
  • These findings suggest greatly elevated 5α-reductase activity in tumorous, as compared with nontumorous, breast tissue.
  • progesterone metabolites that retain the C-4 double bond (i.e., the 4-pregnenes) exert an antiproliferative effect in the three cell lines that were tested, whereas the 5α-pregnanes stimulate breast cell line proliferation.
  • the degree of mitogenicity would be determined by the ratio of 5α-pregnanes:4-pregnenes. Tissues with a high 4-pregnene:5α-pregnane ratio would maintain a higher degree of normalcy, whereas those with a high 5α-pregnane:4-pregnene ratio would tend toward tumorigenicity
  • The observations that progesterone metabolites affect both ER-positive and ER-negative cells as well as tumorigenic (MCF-7) and nontumorigenic (MCF-10A) cells strengthen the argument that these factors may be endocrinologically relevant for all forms of breast cancer.
  • progesterone metabolites as the active endocrine/paracrine/autocrine factors
  • Estrogen-based therapies elicit responses in only one-third of all breast cancer patients, and most of these show relapse.
  • the metabolic activities were in general similar, regardless of the age and ER state of the patient or whether she was pre- or postmenopausal.
    • Nathan Goodyear
      Nathan Goodyear on 27 Jan 14
       
      Interesting that the effect of progesterone metabolites were found to be independent from ER status, age, and pre/post menopause
  • Nathan Goodyear on 17 Feb 12
     
    Different progesterone metabolites shown to have different tumor effects.  Implications are that, just as estrogen metabolism effects cancer risk, so does progesterone metabolism.
Nathan Goodyear

Inflammation and insulin resistance 10.1016/j.febslet.2007.11.057 : FEBS Letters | Scie... - 0 views

www.sciencedirect.com/...S0014579307012082

inflammation insulin resistance IR PPAR TNF-alpha IL-6 IL-10 IL-1Beta JNK GLT-4 Resistin adiponectin Gherlin NF-kapppB iNOS lkkb obesity TLR-4

shared by Nathan Goodyear on 10 Jan 12 - No Cached
  • A subsequent study by Yuan et al. showed that Tnf treatment of 3T3L1 adipocytes induces insulin resistance and that this could be prevented by pretreatment of cells with aspirin
  • Activation of the Tnf receptor results in stimulation of NFκB signaling via Ikkb
  • Insulin is a pleiotropic hormone
  • ...25 more annotations...
  • the percentage of macrophages in a given adipose tissue depot is positively correlated with adiposity and adipocyte size
  • Il-10 is an anti-inflammatory cytokine produced by macrophages and lymphocytes
  • Il-10 exerts its anti-inflammatory activity by inhibiting Tnf-induced NFκB activation by reducing IKK activity [38]
  • adipose tissue macrophages are responsible for nearly all adipose tissue Tnf expression and a significant portion of Nos2 and Il6 expression
  • One theory holds that the expansion of adipose tissue leads to adipocyte hypertrophy and hyperplasia and that large adipocytes outstrip the local oxygen supply leading to cell autonomous hypoxia with activation of cellular stress pathways
  • The use of the anti-inflammatory compounds, salicylate and its derivative aspirin, for treating symptoms of T2DM dates back over 100 years
  • elevated levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin (IL-8) have all been reported in various diabetic and insulin resistant states
  • overnutrition and obesity are often accompanied by elevations in tissue and circulating FFA concentrations, and saturated FFAs can directly activate pro-inflammatory responses
  • Adipokines such as resistin, leptin and adiponectin, which are secreted by adipocytes, can also affect inflammation and insulin sensitivity
  • In skeletal muscle insulin promotes glucose uptake by stimulating translocation of the GLUT4 glucose transporter
  • macrophages are also capable of undergoing a phenotypic switch from an M1 state, which was defined as the “classically activated” pro-inflammatory macrophage, to the M2 state or the “alternatively activated” non-inflammatory cell
  • saturated fatty acids are the most potent inducers of this inflammatory response
  • Several inducers of insulin resistance, including FFAs, pro-inflammatory cytokines and oxidative stress, activate the expression of Nos2, the gene that encodes iNOS (reviewed in [33]
  • Adipose tissue insulin signaling results in decreased hormone sensitive lipase activity and this anti-lipolytic effect inhibits free fatty acid (FFA) efflux out of adipocytes.
  • In the liver, insulin inhibits the expression of key gluconeogenic enzymes and, therefore, insulin resistance in liver leads to elevated hepatic glucose production
  • elevated JNK activity in liver, adipose tissue and skeletal muscle of obese insulin resistant mice, and knockout of Jnk1 (Jnk1−/−) leads to amelioration of insulin resistance in high fat diet
  • Adipose tissue from obese mice contains proportionately more M1 macrophages, whereas, lean adipose tissue contains more M2 macrophages, and increased M1 content positively correlates with inflammation, macrophage infiltration and insulin resistance
  • C-reactive protein (CRP)
  • these studies highlight the possibility that increased iNOS activity plays a direct role in the pathogenesis of insulin resistance
  • the important role of Ikkb in the development of obesity and inflammation-induced insulin resistance.
  • It is probable that local concentrations of inflammatory mediators, such as FFAs, Tnf or other cytokines/adipokines contribute to this polarity switch
  • Tnf and other cytokines/chemokines are symptomatic of inflammation, and while they propagate and/or maintain the inflammatory state, they are not the initial cause(s) of inflammation
  • Tlr4, in particular, is stimulated by lipopolysaccharide (LPS), an endotoxin released by gram-negative bacteria
  • Tlr4 belongs to the family of Toll-like receptors that function as pattern recognition receptors that guard against microorganismal infections as part of the innate immune system.
  • Tlr4 stimulation results in the activation of both Ikkb/NFκB and JNK/AP-1 signaling, culminating in the expression and secretion of pro-inflammatory cytokines/chemokines, including, Il1b, IL-6, Tnf, Mcp1, etc. (reviewed in [57
  • Nathan Goodyear on 10 Jan 12
     
    Great review of all the known components in the inflammation, insulin resistance link
Nathan Goodyear

PPARs, Obesity, and Inflammation - 0 views

www.ncbi.nlm.nih.gov/...PMC1783744

obesity inflammation PPARs perioxisome proliferator-activated receptor

shared by Nathan Goodyear on 16 Jan 12 - No Cached
  • increase of 61% within 10 years
  • Many of the inflammatory markers found in plasma of obese individuals appear to originate from adipose tissue
  • obesity is a state of chronic low-grade inflammation that is initiated by morphological changes in the adipose tissue.
  • ...19 more annotations...
  • secretion of MCP-1, resistin, and other proinflammatory cytokines is increased by obesity, the adipose secretion of the anti-inflammatory protein adiponectin is decreased
  • the peroxisome proliferators- activated receptor (PPAR) family are involved in the regulation of inflammation and energy homestasis
  • natural agonists, including unsaturated fatty acids and eicosanoids
  • PPARα also regulates inflammatory processes, mainly by inhibiting inflammatory gene expression
  • upregulation of COX-2 is seen in alcoholic steatohepatitis and nonalcoholic steatohepatitis and has been directly linked to the progression of steatosis to steatohepatitis, the inhibitory effect of PPARα on COX-2 may reduce steatohepatitis
  • PPARα agonists have a clear anorexic effect resulting in decreased food intake, evidence is accumulating that PPARα may also directly influence adipose tissue function, including its inflammatory status.
  • PPARα may govern adipose tissue inflammation in three different ways: (1) by decreasing adipocyte hypertrophy, which is known to be connected with a higher inflammatory status of the tissue [3, 11, 59], (2) by direct regulation of inflammatory gene expression via locally expressed PPARα, or (3) by systemic events likely originating from liver
  • PPARγ is considered the master regulator of adipogenesis
  • Unsaturated fatty acids and several eicosanoids serve as endogenous agonists of PPARγ
  • PPARγ2, which is adipose-tissue specific
  • two different molecular mechanisms have been proposed by which anti-inflammatory actions of PPARγ are effectuated: (1) via interference with proinflammatory transcription factors including STAT, NF-κB, and AP-1
  • and (2) by preventing removal of corepressor complexes from gene promoter regions resulting in suppression of inflammatory gene transcription
  • diet-induced obesity is associated with increased inflammatory gene expression in adipose tissue via adipocyte hypertrophy and macrophage infiltration
  • PPARγ is able to reverse macrophage infiltration, and subsequently reduces inflammatory gene expression
  • Inflammatory adipokines mainly originate from macrophages which are part of the stromal vascular fraction of adipose tissue [18, 19], and accordingly, the downregulation of inflammatory adipokines in WAT by PPARγ probably occurs via effects on macrophages
  • By interfering with NF-κB signaling pathways, PPARγ is known to decrease inflammation in activated macrophages
  • Recent data suggest that activation of PPARγ in fatty liver may protect against inflammation
  • PPARs may influence the inflammatory response either by direct transcriptional downregulation of proinflammatory genes
  • anti-inflammatory properties of PPARs in human obesity
  • Nathan Goodyear on 16 Jan 12
     
    PPARs play pivotal in obesity.  PPARs appear to reduce the inflammatory cascade associated with obesity.  Downregulation of PPARs are associated with increased inflammation.  Natural PPARs include unsaturated fats and eicosanoids.
Nathan Goodyear

Biological functions and clinical implications of oestrogen receptors alfa and beta in ... - 0 views

onlinelibrary.wiley.com/...full

ER estrogen receptors ER-alpha ER alpha ER-beta ER beta hormones hormone

shared by Nathan Goodyear on 21 Jan 14 - No Cached
  • ERα-positive cells respond to E2 with increased proliferation
  • ERβ was artificially introduced into these cells, E2-induced proliferation was inhibited
  • The proliferative response to E2 seems to be determined by the ratio of ERα/ERβ. The functions of ERβ in the breast are probably related to its antiproliferative as well as its prodifferentiative functions
  • ...7 more annotations...
  • The risk of developing PC seems to be related to the diet
  • In the human prostate, ERβ is expressed in the basal epithelial cells and AR in the luminal epithelium.
  • For many years, DHT was considered to be the main hormone guiding prostate development and function. However, the idea was challenged when in 2001 Mahendroo et al. showed that mice in which both forms of 5α-reductase had been inactivated, have a normal functional prostate [50]. The question was then raised as to what is the real function of DHT in the prostate. In 1989 we hypothesized that DHT is a precursor of an oestrogen, 5α-androstane-3β,17β-diol (3β-Adiol) and that physiological levels of an oestrogen could be produced in the total absence of aromatase [51]. We later demonstrated that 3β-Adiol is abundant in the prostate and is a good natural ligand for ERβ
  • The overall effect of oestrogens in the immune system is determined by a balance between ERα and ERβ signalling
  • The hypothesis of our group is that ERβ plays an important role in regulating the differentiation of pluripotent haematopoietic progenitor cells whereas ERα induces proliferation
  • In tissues and cell lines of mammary epithelium for example, it has been noticed that E2 in the presence of ERα elicits proliferation, but in the presence of ERβ it inhibits proliferation
  • ERα and ERβ have distinctive tissue distributions and to the great surprise of endocrinologists [7] many tissues previously thought to be ‘oestrogen-insensitive tissues’ were found to be ERβ positive and oestrogen sensitive. The most notable of the ERα-negative ERβ-abundant tissues were the epithelium of the rodent ventral prostate [8], the granulosa cells of the ovaries [9] and the parenchyma of the lungs
  • Nathan Goodyear on 21 Jan 14
     
    Awesome article discusses the different balance of ER alpha and ER beta and the effects on tissue as it relates to proliferation versus differentiation.  This has clear implications in disease.  Physicians prescribing hormones without a knowledge and understanding of this are only causing potential harm to their clients.
Nathan Goodyear

American Journal of Obstetrics & Gynecology Home Page - 0 views

www.ajog.org/...fulltext

"Vaginal mesh" immune system

shared by Nathan Goodyear on 31 Aug 18 - No Cached
  • M1 macrophages are characterized by the secretion of reactive oxygen species and proinflammatory cytokines and chemokines and can be identified via the cell surface marker CD86
  • M2 macrophages secrete growth factors and antiinflammatory immune modulators and can be identified by the cell surface marker CD206
  • an overzealous M2 response can also lead to excess tissue deposition and fibrosis
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  • Studies of similar meshes that are used in hernia repair have demonstrated that all polypropylene meshes induce a prolonged inflammatory response at the site of implantation
  • the long-term presence of activated inflammatory cells, such as macrophages at the mesh tissue interface, can impact negatively the ability of the mesh to function as intended.
  • All M1 proinflammatory and M2 proremodeling cytokines and chemokines were increased in mesh explants as compared with nonmesh tissue (Table 3Table 3), which indicated a robust, active, and ongoing host response to polypropylene long after implantation
  • Comparison of the ratio of the M2 proremodeling cytokines (IL-10+IL-4) with the M1 proinflammatory cytokines (TNF-α+IL-12p70) revealed a decrease in mesh explants as compared with controls (P = .003), which indicated a shift towards a proinflammatory profile.
  • Mesh explants contained a higher number of total cells/×200 field when compared with controls (682.46 ± 142.61 cells vs 441.63 ± 126.13 cells; P < .001) and a lower ratio of M2:M1 macrophages (0.260 ± 0.161 cells vs 1.772 ± 1.919; P = .001), which supported an ongoing proinflammatory response.
  • the host response was proportional to the amount of material in contact with the host
  • A persistent foreign body response was observed in mesh-tissue complexes that were excised from women who required surgical excision of mesh months to years after mesh implantation
  • The host response was characterized by a predominance of macrophages with an increase in both proinflammatory and proremodeling cytokines/chemokines along with increased tissue degradation, as evidenced by increased MMP-2 and -9
  • Mesh-tissue complexes removed for mesh exposure had increased pro–MMP-9 that indicated a proinflammatory and tissue destruction–type response
  • The presence of macrophages, elevated cytokines, chemokines, and MMPs in tissue-mesh complexes that were excised from patients with exposure or pain suggests that polypropylene mesh elicits an ongoing host inflammatory response
  • In the presence of a permanent foreign body, the implant is surrounded with a fibrotic capsule because it cannot be degraded
  • For hernia meshes, if the fibers are too close (<1 mm), the fibrotic response to neighboring fibers overlaps, or “bridges,” and results in “bridging fibrosis” or encapsulation of the mesh
  • Gynemesh PS has a highly unstable geometry when loaded that resulted in pore collapse and increasing stiffness of the product
  • mesh shrinkage (50-70%) has been described to occur after transvaginal insertion of prolapse meshes
  • Nathan Goodyear on 31 Aug 18
     
    Mesh and the abnormal immune response.
Nathan Goodyear

Late Disseminated Lyme Disease: Associated Pathology and Spirochete Persistence Post-Tr... - 0 views

ajp.amjpathol.org/...fulltext

Lyme Lyme disease borrelia burgdorferi

shared by Nathan Goodyear on 14 Dec 17 - No Cached
  • In this study, we have demonstrated microscopic pathology ranging from minimal to moderate in multiple different tissues previously reported to be involved with LD, including the nervous system (central and peripheral), heart, skeletal muscle, joint-associated tissues, and urinary bladder 12 to 13 months following tick-inoculation of rhesus macaques by Bb strain B31
  • Based on histomorphology, inflammation consisted predominantly of lymphocytes and plasma cells, with rare scattered histiocytes
  • in rare instances, morphologically intact spirochetes were observed in inflamed brain and heart tissue sections from doxycycline-treated animals
  • ...41 more annotations...
  • colocalization of the Bb 23S rRNA probe was not observed in any of the sections of experimental inoculated animals shown to harbor rare persistent spirochetes (Supplemental Figure S1). Previous in vitro work has shown large decreases in Bb rRNA levels when in a stationary phase of growth despite the majority of spirochetes remaining viable
  • The possibility that the spirochetes were intact but dead also exists, though this may be unlikely given the precedence for viable but non-cultivable B. burgdorferi post-treatment
  • The doxycycline dose utilized in this study (5mg/kg) was based on a previous pharmacokinetic analysis of oral doxycycline in rhesus macaques proven to be comparable to levels achieved in humans and was meant to mimic treatment of disseminated LD
  • In addition to the brain of two treated animals, rare morphologically intact spirochetes immunoreactive to OspA were observed in the heart of one treated animal
  • Although we did not measure the doxycycline levels in the cerebrospinal fluid, they have been found to be 12% to 15% of the amount measured in serum
  • We and others have demonstrated the development of a drug-tolerant persister population when B. burgdorferi are treated with antibiotics in vitro
  • The adoption of a dormant or slow-growing phenotype likely allows the spirochetes to survive and re-grow following removal of antibiotic
  • The basic premise that antibiotic tolerance may be an adaptation of the sophisticated stringent response required for the enzootic cycle by the spirochetes is described in a recent review as well
  • Although current IDSA guidelines recommend intravenous ceftriaxone (2g daily for 30 days) over oral doxycycline for treatment of neuroborreliosis, a randomized clinical trial failed to show any enhanced efficacy of I.V. penicillin G to oral doxycycline for treatment of Lyme neuroborreliosis (no treatment failures were reported in this study of 54 patients).
  • we can speculate that the minimal to moderate inflammation that was observed, especially within the CNS and PNS can, in part, explain the breadth of symptoms experienced by late stage Lyme disease patients, such as cognitive impairment and neuralgia.
  • Erythema migrans, the clinical hallmark of early localized Lyme disease, was observed in one of the rhesus macaques from this study.
  • In 2014, a trailblazing study in mice demonstrated a dramatic decline in B. burgdorferi DNA in the tissues for up to eight months after antibiotic treatment followed by the resurgence of B. burgdorferi growth 12 months after treatment
  • This study provides evidence that the slow-growing spirochetes which persist after treatment, but are not cultivable in standard growth media may remain viable.
  • The first well-documented indication of Lyme disease (LD) in the United States occurred in the early 1970s
  • Lyme, Connecticut.
  • Lyme disease is now known to be caused by multiple closely related genospecies classified within the Bb sensu lato complex, representing the most common tick-borne human disease in the Northern Hemisphere
  • approximately 30,000 physician-reported cases occur annually in the United States, the annual incidence has been estimated to be 10-fold higher by the Centers for Disease Control and Prevention.6
  • Current antibiotic therapy guidelines outlined by the Infectious Disease Society of America (IDSA) are successful in the treatment of LD for the majority of LD patients, especially when administered early in disease immediately following identification of erythema migrans (EM)
  • ‘post-treatment Lyme disease syndrome’ (PTLDS)
  • host-adapted spirochetes that persist in the tissues, probably in small numbers, inaccessible or impervious to antibiotic
  • inflammatory responses to residual antigens from dead organisms
  • residual tissue damage following pathogen clearance;
  • autoimmune responses, possibly elicited by antigenic mimicry
  • Experimental studies on immunocompetent mice, dogs, and rhesus macaques have provided evidence for the persistence of Bb spirochetes subsequent to antibiotic treatment in the form of residual spirochetes detected within tissue by IFA and PCR, and recovered by xenodiagnoses
  • Ten male rhesus macaques
  • half (five) of the NHP received antibiotic treatment, consisting of 5 mg/kg oral doxycycline twice per day.
  • Minimal and focal lymphoplasmacytic inflammation
  • inflammation was observed in the leptomeninges overlying a section of temporal cerebral cortex
  • Minimal localized lymphoplasmacytic choroiditis
  • Peripheral nerves contained minimal to moderate lymphoplasmacytic inflammation with a predilection for collagen-rich epineurium and perivascular spaces
  • Inflammation was observed in 56% (5/9) of the NHPs irrespective of treatment group
  • For all animals, inflammation was reserved to perineural tissue
  • The treatment lasted 28 days
  • Minimal to mild lymphoplasmacytic inflammation of either the myocardial interstitium (Figure 2Figure 2A), pericardium (Figure 2Figure 2B), or combination therein was observed in 60% of NHPs
  • A single morphologically intact spirochete, as indicated by positive red immunofluorescence (Figure 2Figure 2C), was observed in the myocardium of one treated animal
  • mild, multifocal lymphoplasmacytic inflammation was observed in one doxycycline-treated animal
  • three animals exhibited minimal to mild lymphoplasmacytic inflammation affecting joint-associated structures
  • 10% to -20% of human patients treated
  • Multiple randomized placebo-controlled studies which evaluated sustained antimicrobial therapy concluded that there is no benefit in alleviating patients’ symptoms and indicated that long-term antibiotic therapy may even be detrimental to patients due to potential associated complications (ie, catheter infection and/or clostridial colitis)
  • and the rapid clearance of dead spirochetes in a murine model
  • higher doses may be needed to combat neuroborreliosis
  • Nathan Goodyear on 14 Dec 17
     
    persistent borrelia burgdorferia were found in the brain (2) and the heart (1) up to 13 months post standard antibiotic treatment suggesting borrelia burdorferia, the cause of Lyme, can persist in a chronic, persistant state poste acute treatment.
fitspresso

https://www.sightcare-co.com/ - 0 views

www.sightcare-co.com

sight care sightcare group training nearsightedness food for eyesight carey codd vitasight vision how to cure bad eye tips fix improve your red light eyes diet improvement skincare malaysia costos de medicare indonesia singapore eyecare

shared by fitspresso on 27 Sep 23 - No Cached
  • fitspresso on 27 Sep 23
     
    Sight Care | Official Site sightcare-co.com · by Sight Care Sight Care Only $49/Bottle Limited Time Offer! Sight Care Special Deal + Special 67% Discount Save $600 + 180 Days Money Back Guarantee #1.The Sight Care vision supplement is a dietary supplement for helping you improve your vision and brain health. Sight Care eye supplements are formulated to provide a synergistic blend of vitamins, minerals, antioxidants, and other bioactive compounds that are essential for maintaining healthy vision Regular Price: 147/per bottle Only for: $49/per bottle What Is Sight Care? This powerful vision support supplement is made with a unique blend of natural ingredients and plant extracts that work together synergistically to deliver numerous benefits for your brain and eye health. With Sight Care, you can expect to experience increased energy levels, improved eyesight, and an overall revitalized sense of well-being. Taking care of your vision health is not just about seeing clearly; it's also about maintaining your overall brain health. As we age, our vision deteriorates, and our eyes and brain can experience a decline in function, but there are steps you can take to support your visual and cognitive health. Regular eye exams are crucial for detecting and treating vision problems early on, and making healthy choices such as eating a nutritious diet and exercising regularly can also help. However, with busy schedules, it can be difficult to find the time to devote to a healthy lifestyle. This is where the Sight Care supplement comes in. It's designed to support both vision and brain health with its blend of natural ingredients that have been shown to promote healthy vision and cognitive function You must not compromise your eye health for momentary exhilaration. If you are glued to digital screens day and night, you must take measures to prevent eye diseases like age-related macular degeneration. The SightCare vision supplement has been made using 100% natura
Nathan Goodyear

ScienceDirect.com - Cell Metabolism - Estrogen Receptors and the Metabolic Network - 0 views

www.sciencedirect.com/...S1550413111003123

ER-alpha ER-beta estrogen receptor receptors metabolic syndrome MetS hormone hormones

shared by Nathan Goodyear on 11 Oct 12 - No Cached
  • The pro-opiomelanocortin (POMC) neurons have an anorexigenic action and, when activated, reduce food intake through the release of two peptides, α-melanocyte-stimulating hormone (α-MSH) and cocaine-and-amphetamine-regulated transcripts (CART). The neuropeptide Y (NPY) neurons, on the other hand, release NPY hormone and agouti gene-related protein (AgRP), which prevent the binding of α-MSH to MC3R and MC4R, increasing food intake
  • This suggests that the central anorexic effects of E2 may occur via ERβ
  • The main hypothalamic areas involved in food intake and satiety are the arcuate nucleus (ARC), the lateral hypothalamus (LH), the paraventricular nucleus (PVN), the ventromedial hypothalamus (VMH), and the dorsomedial hypothalamus (DMH)
  • ...22 more annotations...
  • Leptin is a potent anorexigenic and catabolic hormone secreted by adipose cells that reduces food intake and increases energy expenditure
  • E2 not only modulates leptin receptor mRNA in the ARC and VMH, but also increases hypothalamic sensitivity to leptin, altering peripheral fat distribution
  • ghrelin. It acts on growth hormone secretagogue receptors (GHSR1a) located in the ARC and is a potent stimulator of food intake
  • It thus appears that of the two ERs, ERα plays a predominant role in the CNS regulation of lipid and carbohydrate homeostasis.
  • Both ERs have been identified in the ARC
  • Stimulation of MCH neurons increases food intake and fat accumulation while its inhibition leads to decreased food intake and reduced fat accumulation.
  • Both ERs have been identified in the LH
  • both ERs have been identified in this nucleus
  • The PVN is the region of the hypothalamus with the highest expression of ERβ and is reported to be weakly ERα positive
  • The VMH is ERα regulated
  • Skeletal muscle is responsible for 75% of the insulin-induced glucose uptake in the body
  • GLUT4 is highly expressed in muscle and represents a rate-limiting step in the insulin-induced glucose uptake
  • data suggest that in the physiological range, E2 is beneficial for insulin sensitivity, whereas hypo- or hyperestrogenism is related to insulin resistance
  • In aging female rats, E2 treatment improves glucose homeostasis mainly through its ability to increase muscle GLUT4 content on the cell membrane
  • It is evident that ERα and ERβ have distinct actions and that much more research is needed to clearly identify the function of each receptor in muscle.
  • E2 prevents accumulation of visceral fat, increases central sensitivity to leptin, increases the expression of insulin receptors in adipocytes, and decreases the lipogenic activity of lipoprotein lipase in adipose tissue
  • In rats, ovariectomy increases body weight, intra-abdominal fat, fasting glucose and insulin levels, and insulin resistance followed by decreased phosphorylation of AMPK and its substrate acetyl-CoA carboxylase in adipose tissue
  • decreased adiponectin, PPARγ coactivator-1α (PGC-1α), and uncoupling protein 2 (UCP2) and increased resistin
  • Men with aromatase deficiency have truncal obesity, elevated blood lipids, and severe insulin resistance
  • Although not all studies are in agreement, polymorphisms of ERα in humans have been associated with risk factors for CVDs
  • Human subcutaneous and visceral adipose tissues express both ERα and ERβ, whereas only ERα mRNA has been identified in brown adipose tissue
  • suggesting that ERα is the main regulator of GLUT4 expression in adipose tissue
  • Nathan Goodyear on 11 Oct 12
     
    very nice article that looks at the balance of ER-alpha/ER-beta and their role in metabolic syndrome.  This article discusses the balance of  these receptors are tissue dependent in their effect.  I like their conclusion: "...but these mechanisms will never be completely understood if they are not considered in the context of a whole system.
Nathan Goodyear

Progesterone metabolites in breast cancer - 1 views

erc.endocrinology-journals.org/...717.full

progesterone metabolism tumor tumorigenesis cancer risk growth hormone hormones 5-beta-pregnanediol 5-alpha-pregnanediol 4-pregnenediol 5-alpha reductase

shared by Nathan Goodyear on 20 Feb 12 - No Cached
  • P metabolites produced within breast tissues might be independently active hormones functioning as cancer-promoting or -inhibiting regulatory agents
  • these P metabolites function as independent pro-or anti-cancer autocrine/paracrine hormones that regulate cell proliferation, adhesion, apoptosis and cytoskeletal, and other cell status molecules via novel receptors located in the cell membrane and intrinsically linked to cell signaling pathways
  • only a fraction of all breast cancer patients respond to this estrogen-based therapy and the response is only temporary
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  • P serves as the precursor for the major steroid hormones (androgens, estrogens, corticosteroids) produced by the gonadal and adrenal cortical tissues.
  • 5α-pregnane, 5β-pregnane, and 4-pregnene metabolites of P
  • These P-metabolizing enzymes included 5α-reductase, 5β-reductase, 3α-hydroxysteroid oxido-reductase (3α-HSO), 3β-HSO, 20α-HSO, 20β-HSO, 6α(β)-, 11β-, 17-, and 21-hydroxylase, and C17–20-lyase
  • Reduction of P to 5α-pregnanes is catalyzed by 5α-reductase and the direct 5α-reduced metabolite of P is 5α-pregnane-3,20-dione (5αP). The 5α-reductase reaction is irreversible
  • The two 4-pregnenes resulting from direct P conversion are 4-pregnen-3α-ol-20-one (3αHP) and 4-pregnen-20α-ol-3-one (20αHP), catalyzed by the actions of 3α-HSO and 20α-HSO respectively
  • the P-metabolizing enzyme activities identified in human breast tissues and cell lines were: 5α-reductase, 3α-HSO, 3β-HSO, 20α-HSO, and 6α-hydroxylase
  • In normal breast tissue, conversion to 4-pregnenes greatly exceeded the conversion to 5α-pregnanes, whereas in tumorous tissue, conversion to 5α-pregnanes greatly exceeded that to 4-pregnenes
  • The results indicated that P 5α-reductase activity is significantly higher, whereas P 3α-HSO and 20α-HSO activities are significantly lower in tumor than in normal tissues
  • he results showed that production of 5α-pregnanes was higher and that of 4-pregnenes was lower in tumorigenic (e.g. MCF-7) than in nontumorigenic (e.g. MCF-10A) cells (Fig. 3c⇑), while differences in ER/P status did not appear to play a role
  • The 5α-pregnane-to-4-pregnene ratios were 7- to 20-fold higher in the tumorigenic than in the nontumorigenic cell lines
  • altered direction in P metabolism, and hence in metabolite ratios, was due to significantly elevated 5α-reductase and depressed 3α- and 20α-HSO activities in breast tumor tissues and tumorigenic cells. It appeared, therefore, that changes in P-metabolizing enzyme activities might be related to the shift toward mammary cell tumorigenicity and neoplasia
  • In vivo, changes in enzyme activity can result from changes in levels of the enzyme due to changes in expression of the mRNA coding for the enzyme, or from changes in the milieu in which the enzyme operates (such as temperature and pH, and concentrations of cofactors, substrates, products, competitors, ions, phospholipids, and other molecules)
  • Overall, the enzyme activity and expression studies strongly suggest that 5α-reductase stimulation and 3α- and 20α-HSO suppression are associated with the transition from normalcy to cancer of the breast
  • The level of expression of 5α-reductase is up-regulated by estradiol and P in the uterus (Minjarez et al. 2001) and by 5α-dihydrotestosterone (DHT) in the prostate
  • 3αHP inhibited whereas 5αP-stimulated proliferation
  • Stimulation in cell numbers was also observed when cells were treated with other 5α-pregnanes, such as 5α-pregnan-3α-ol-20-one, 5α-pregnan-20α-ol-3-one, and 5α-pregnane-3α,20α-diol, whereas other 4-pregnenes such as 20α-HP and 4-pregnene-3α,20α-diol resulted in suppression of cell proliferation
  • Stimulation of cell proliferation with 5αP and inhibition with 3αHP were also observed in all other breast cell lines examined, whether ER/P-negative (MCF-10A, MDA-MB-231) or ER/P-positive (T47D, ZR-75-1) and whether requiring estrogen for tumorigenicity (MCF-7, T47D) or not (MDA-MB-231), or whether they are nontumorigenic (
  • αHP resulted in significant increases in apoptosis and decreases in mitosis, leading to significant decreases in total cell numbers. In contrast, treatment with 5αP resulted in decreases in apoptosis and increases in mitosis.
  • The opposing actions of 5αP and 3αHP on both cell anchorage and proliferation strengthen the hypothesis that the direction of P metabolism in vivo toward higher 5α-pregnane and lower 4-pregnene concentrations could promote breast neoplasia and lead to malignancy.
  • he effects on proliferation and adhesion were not due to P, but due to the 5α-reduced metabolites
  • The studies showed that binding of 5αP or 3αHP occurs in the plasma membrane fractions, but not in the nuclear or cytosolic compartments
  • separate high-specificity, high-affinity, low- capacity receptors for 5αP and 3αHP that are distinct from each other and from the well-studied nuclear/cytosolic P, estrogen, and androgen and corticosteroid receptors
  • The studies thus provided the first demonstration of the existence of specific P metabolite receptors
  • the receptor results suggest that the putative tumorigenic actions of 5αP may be significantly augmented by the estradiol-induced increases in 5αP binding and decreases in 3αHP binding.
  • Estradiol and 5αP resulted in significant dose-dependent increases, whereas 3αHP and 20αHP each resulted in dose-dependent decreases in total ER
  • In combination, estradiol + 5αP or 3αHP + 20αHP resulted in additive increases or decreases respectively in ER numbers.
  • The data suggest that the action of 5αP on breast cancer cells involves modulation of the MAPK signaling pathway
  • current evidence does not appear to support the notion that increased 5α-reductase activity/ expression might significantly alter androgen influences on breast tumor growth.
  • both testosterone and DHT inhibit cell growth more or less to the same extent
  • Note that 5α-reductase reaction is not reversible
  • Nathan Goodyear on 20 Feb 12
     
    Fantastic read on the effects of progesterone metabolism on tumor and cancer growth.  Tumorigenesis is not just about the hormone, hormone balance, but about the metabolism of hormones.  This is why premarin is so carcinogenic: it is primarily metabolized by the 4-OH estrone pathway.
Nathan Goodyear

Progesterone metabolites regulate induction, growth, and suppression of estrogen- and p... - 0 views

www.ncbi.nlm.nih.gov/...PMC3706910

progesterone metabolites metabolite 5-alpha pregnene 5-alpha pregnenes 5alpha-dihydroprogesterone 4-pregnene 4-pregnenes 3alpha-dihydroprogesterone breast cancer ER PR hormone hormones receptors estrogen

shared by Nathan Goodyear on 28 Jan 14 - No Cached
  • in vitro studies had shown that the progesterone metabolites, 5α-dihydroprogesterone (5αP) and 3α-dihydroprogesterone (3αHP), respectively, exhibit procancer and anticancer effects on receptor-negative human breast cell lines
  • Onset and growth of ER/PR-negative human breast cell tumors were significantly stimulated by 5αP and inhibited by 3αHP
  • When both hormones were applied simultaneously, the stimulatory effects of 5αP were abrogated by the inhibitory effects of 3αHP and vice versa
  • ...31 more annotations...
  • Treatment with 3αHP subsequent to 5αP-induced tumor initiation resulted in suppression of further tumorigenesis and regression of existing tumors
  • Tumorigenesis of ER/PR-negative breast cells is significantly enhanced by 5αP and suppressed by 3αHP, the outcome depending on the relative concentrations of these two hormones in the microenvironment in the breast regions
  • The findings show that the production of 5αP greatly exceeds that of 3αHP in ER/PR-negative tumors and that treatment with 3αHP can effectively block tumorigenesis and cause existing tumors to regress
  • hypothesis that a high 3αHP-to-5αP concentration ratio in the microenvironment may foster normalcy in noncancerous breast regions.
  • a large proportion (about 30% to 60%) of breast tumors are ER and/or PR negative
  • about 90% of normal proliferating breast epithelial cells are receptor negative
  • Our previous in vitro studies had shown that breast tissues and cell lines readily convert progesterone to 5α-pregnanes, such as 5αP, and delta-4-pregnenes, such as 3αHP (Figure ​(Figure1),1), and that tumorous breast tissues [15] and tumorigenic breast cell lines [16] produce higher levels of 5αP and lower levels of 3αHP than do normal breast tissues and nontumorigenic cell lines
  • The progesterone metabolism studies suggested that increases in 5αP and decreases in 3αHP production accompany the shift toward breast cell neoplasia and tumorigenicity
  • In vitro studies on five different human breast cell lines showed that cell proliferation and detachment are significantly increased by 5αP and decreased by 3αHP
  • the prevailing theory of hormonal regulation of breast cancer, as well as hormone-based therapies, revolves around estrogen and/or progesterone and ER/PR-positive breast cells and tumors.
  • Not only do these "receptor-negative" breast cancers fail to benefit from current hormonal therapies, but they also generally exhibit more-aggressive biologic behaviors and poorer prognosis than the receptor-positive ones
  • The results of the studies reported here show for the first time that the progesterone metabolites, 5αP and 3αHP, act as hormones that regulate ER/PR-negative breast tumor formation, growth, and regression
  • The onset of the ER/PR-negative human breast cell tumors in mice was considerably accelerated, and the growth significantly stimulated, by just one or two applications of 5αP
  • In contrast, 3αHP retarded onset of tumor formation, suppressed tumor growth, and inhibited or regressed existing 5αP-induced tumors
  • When both hormones were administered simultaneously, the effects of one were abrogated by the effects of the other.
  • The 5αPR and 3αHPR (which are associated with the plasma membranes of both ER/PR-positive [19] and ER/PR-negative [29] cells) are distinct from each other and from known ER, PR, androgen, and corticosteroid receptors, and lack affinity for other steroids, such as progesterone, estrogen, androgens, corticosteroids, and other progesterone metabolites
  • Levels of 5αPR are upregulated by 5αP itself and estradiol, and downregulated by 3αHP in both ER/PR-positive and -negative cells
  • ndications are that 5αP acts via the surface receptor-linked mitogen-activated protein kinase (MAPK; Erk1/2) pathway; 5αP significantly stimulates activation of Erk1/2 [30], increases the Bcl-2/Bax expression ratio [18] and actin depolymerization [31], and decreases expression of actin and adhesion plaque-associated vinculin [31], resulting in decreased apoptosis and increased mitosis and cell detachment
  • 3αHP appears to suppress protein kinase C (PKC), phospholipase C (PLC), Ca2+ mobilization (unpublished observations), and the Bcl-2/Bax expression ratio [18], and increases expression of the cell-cycle inhibitor p21 [18], resulting in increased apoptosis and decreased proliferation and detachment of breast cell lines.
  • serum from mice with tumors had significantly more 5αP than 3αHP
  • the tumors, which on average had about threefold higher concentrations of 5αP than the respective sera, and >10-fold higher 5αP than 3αHP levels
  • Previous in vitro metabolism studies showed that human breast tumor tissues convert significantly more progesterone to 5α-pregnanes like 5αP and less to 4-pregnenes like 3αHP than do paired normal (nontumorous) tissues
  • Similar differences in progesterone metabolism and enzyme gene expressions were observed between tumorigenic and nontumorigenic breast cell lines
  • breast carcinomas are able to synthesize progesterone
  • The current findings, along with the previous in vitro studies, suggest that the relative concentrations of 5αP and 3αHP in the breast microenvironment constitute important autocrine/paracrine determinants not only for tumorigenesis but also for potential regression of tumors and the maintenance of normalcy of ER/PR-negative breast cells/tissues.
  • Evidence presented here shows that a high concentration of 5αP, relative to 3αHP in the microenvironment, promotes initiation and growth of tumors, whereas a higher concentration of 3αHP, relative to 5αP, suppresses tumorigenesis and promotes normalcy
  • 5α-reductase and 5αPR levels are upregulated by 5αP
  • in the 3αHP-treated mice, the elevated 3αHP levels, relative to 5αP, in the microenvironment could have opposed progression to xenograft neoplasia by its inherent anticancer actions and the suppression of 5αP synthesis and 5αPR expression
  • the opposing actions of the progesterone metabolites also appear to exert some control over the estrogen-regulated effects on breast cancer by their ability to modulate ER numbers in ER-positive cells
  • because both ER/PR-negative and ER/PR-positive, as well as normal and tumorigenic human breast cell lines, have been shown to respond to 5αP and 3αHP in vitro, it is suggested that these endogenously produced progesterone metabolites may also play regulatory hormonal roles in ER/PR-positive breast cancers, as well as in the maintenance of normalcy in nontumorous breast tissues.
  • The in vivo data provide further evidence that progesterone metabolites, such as 5αP and 3αHP, deserve to be considered as active hormones in their own right, rather than inactive waste products
  • Nathan Goodyear on 28 Jan 14
     
    Progesterone metabolites and breast cancer
Nathan Goodyear

Adipose Tissue Recruitment of Leukocytes - 0 views

www.ncbi.nlm.nih.gov/...PMC3381420

obesity adipose tissue macrophages M1 M2 IR insulin resistance inflammation

shared by Nathan Goodyear on 04 Jan 13 - No Cached
  • Nathan Goodyear on 04 Jan 13
     
    good discussion on how adipose tissue recruits macrophages and increases inflammatory signaling initiating insulin resistance.  This reveals how adipose tissue is extremely active.
Nathan Goodyear

The Role of Androgen in the Adipose Tissue of Males - 0 views

www.ncbi.nlm.nih.gov/...PMC3770848

obesity fat adipose tissue Testosterone aromatase DHT androgens male hormones hormones leptin inflammation men

shared by Nathan Goodyear on 18 Nov 16 - No Cached
  • Nathan Goodyear on 18 Nov 16
     
    great review of the current knowledge of how adipose tissue influences androgen production and how androgens influence adipose tissue.  For example, leptin has an androgen inhibition centrally and peripherally.
Nathan Goodyear

Adrenocortical dysregulation as a major player in insulin resistance and onset of obesity - 0 views

ajpendo.physiology.org/...E1465.long

cortisol insulin resistance metabolic syndrome obesity overweight

shared by Nathan Goodyear on 14 Mar 12 - No Cached
  • acute GC secretion during stress mobilizes peripheral amino acids from muscle as well as fatty acids and glycerol from peripheral fat stores to provide substrates for glucose synthesis by the liver
  • chronically elevated GC levels alter body fat distribution and increase visceral adiposity as well as metabolic abnormalities in a fashion reminiscent of metabolic syndrome
  • This local production may play an important role in the onset of obesity and insulin resistance.
  • ...9 more annotations...
  • In adipocytes, cortisol inhibits lipid mobilization in the presence of insulin, thus leading to triglyceride accumulation and retention.
  • Since the density of GC receptors is higher in intra-abdominal (visceral) fat than in other fat depots, the activity of cortisol leading to accumulation of fat is accentuated in visceral adipose tissue (24, 158), providing a mechanism by which excessive endogenous or exogenous GC lead to abdominal obesity and IR
  • obese patients generally have normal or subnormal plasma cortisol concentrations
  • This may be explained by an increased intratissular/cellular concentration of cortisol in adipose tissues
  • Intracellular GC may be produced from recycling of GC metabolites such as cortisone in adipose tissues
  • Local GC recycling metabolism is mediated by 11β-hydroxysteroid dehydrogenase enzymes (11β-HSD1 and 11β-HSD2
  • Cortisol also increases 11β-HSD1 expression in human adipocytes
  • In humans, elevated 11β-HSD1 expression in visceral adipose tissue is also associated with obesity
  • even if obese patients generally have normal or subnormal plasma cortisol concentrations (131, 158), triglyceride accumulation in visceral adipose tissue may be due, at least in part, to the local production of GC in insulin- and GC-responsive organs such as adipose tissue, liver, and skeletal muscle
  • Nathan Goodyear on 14 Mar 12
     
    another nice article on the dysregulation of cortisol and its role in insulin resistance, metabolic syndrome, and obesity.
Nathan Goodyear

Effect of DHEA-sulfate on adiponectin gene expression in adipose tissue from different ... - 0 views

www.eje.org/...593.full

DHEA-S DHEAS adiponectin adipose tissue adipocytes fat cells insulin resistance obesity

shared by Nathan Goodyear on 17 Mar 12 - No Cached
  • Nathan Goodyear on 17 Mar 12
     
    DHEA-S shown to increase genetic expression of adiponectin in human adipose tissue.  This has enormous implications on the link between DHEA and insulin resistance induce obesity. This is a peripheral tissue problem, not a central problem.
Nathan Goodyear

Obesity is associated with macrophage accumulation in adipose tissue - 0 views

www.ncbi.nlm.nih.gov/...PMC296995

obesity inflammation overweight weight-loss WAT white adipose tissue M1 macrophages

shared by Nathan Goodyear on 16 Jan 12 - No Cached
  • Nathan Goodyear on 16 Jan 12
     
    obesity is associated with dysfunctional immune response to adipose tissue.  The cause is inflammation from White adipose tissue resultant in increased recruitment of macrophages and resultant further inflammation.  M1 macrophages are the predominate culprit.
Nathan Goodyear

Progesterone metabolites in breast cancer - 0 views

erc.endocrinology-journals.org/...717.long

progesterone metabolism metabolites breast cancer hormones progesterone metabolites

shared by Nathan Goodyear on 12 Jun 14 - No Cached
  • In breast tumor tissue and tumorigenic cell lines, 5α-reductase activity and mRNA expression are significantly higher, whereas 3α- and 20α-HSO activities and mRNA expression are significantly lower than in normal breast tissue and nontumorigenic cells
  • Studies using various breast cell lines have shown that 5αP and 3αHP have opposing actions in terms of cell proliferation and adhesion; 5αP stimulates cell proliferation (through increased mitosis and decreased apoptosis) and cell detachment, whereas 3αHP suppresses cell proliferation (through decreased mitosis and increased apoptosis) and detachment
  • the paracrine/ autocrine functions of 5αP are cancer-promoting and those of 3αHP are cancer-inhibiting
  • Nathan Goodyear on 12 Jun 14
     
    Awesome article on progesterone metabolism in breast cancer.  The author, weibe, describes 2 categories of progesterone metabolites in breast tissue: 5alpha-pregnanes and 4-pregnenes.  The author describes 3 primary enzymes that control the balance between these 2 metabolites--5alpha reductase, 3alpha-HSO, and 20alpha-HSO.  The resultant balance of 5alpha-dihydroprogesterone and 3alpha-dihydroprogesterone helps to determine the cancer potential of breast tissue.
Nathan Goodyear

Effects of Hypo- and Hyperthyroidism on Noradrenergic Activity and Glycerol Concentrati... - 0 views

press.endocrine.org/...jc.2003-030576

thyroid hormone adipose tissue adipose fat obesity metabolism noradrenaline norepinephrine

shared by Nathan Goodyear on 24 Sep 14 - No Cached
  • Nathan Goodyear on 24 Sep 14
     
    Thyroid hormone increased localized norepinephrine production and liposlys resulting in decreases SQ adipose tissue compared to hypothyroid.  This study showed a localized effect of adipose tissue by thyroid hormone. 
Nathan Goodyear

Testosterone: a metabolic hormone in health and disease - 0 views

joe.endocrinology-journals.org/...R25.full

male hormone hormones testosterone hypogonadal-obesity-adipocytokine hypothesis

shared by Nathan Goodyear on 08 May 13 - No Cached
  • E2 and the inflammatory adipocytokines tumour necrosis factor α (TNFα) and interleukin 6 (IL6) inhibit hypothalamic production of GNRH and subsequent release of LH and FSH from the pituitary
  • Leptin, an adipose-derived hormone with a well-known role in regulation of body weight and food intake, also induces LH release under normal conditions via stimulation of hypothalamic GNRH neurons
  • In human obesity, whereby adipocytes are producing elevated amounts of leptin, the hypothalamic–pituitary axis becomes leptin resistant
  • ...39 more annotations...
  • there is evidence from animal studies that leptin resistance, inflammation and oestrogens inhibit neuronal release of kisspeptin
  • Beyond hypothalamic action, leptin also directly inhibits the stimulatory action of gonadotrophins on the Leydig cells of the testis to decrease testosterone production; therefore, elevated leptin levels in obesity may further diminish androgen status
  • Prostate cancer patients with pre-existing T2DM show a further deterioration of insulin resistance and worsening of diabetic control following ADT
  • ADT for the treatment of prostatic carcinoma in some large epidemiological studies has been shown to be associated with an increased risk of developing MetS and T2DM
  • Non-diabetic men undergoing androgen ablation show increased occurrence of new-onset diabetes and demonstrate elevated insulin levels and worsening glycaemic control
  • increasing insulin resistance assessed by glucose tolerence test and hypoglycemic clamp was shown to be associated with a decrease in Leydig cell testosterone secretion in men
  • The response to testosterone replacement of insulin sensitivity is in part dependent on the androgen receptor (AR)
  • Low levels of testosterone have been associated with an atherogenic lipoprotein profile, characterised by high LDL and triglyceride levels
  • a positive correlation between serum testosterone and HDL has been reported in both healthy and diabetic men
  • up to 70% of the body's insulin sensitivity is accounted for by muscle
  • Testosterone deficiency is associated with a decrease in lean body mass
  • relative muscle mass is inversely associated with insulin resistance and pre-diabetes
  • GLUT4 and IRS1 were up-regulated in cultured adipocytes and skeletal muscle cells following testosterone treatment at low dose and short-time incubations
  • local conversion of testosterone to DHT and activation of AR may be important for glucose uptake
  • inverse correlation between testosterone levels and adverse mitochondrial function
  • orchidectomy of male Wistar rats and associated testosterone deficiency induced increased absorption of glucose from the intestine
  • (Kelley & Mandarino 2000). Frederiksen et al. (2012a) recently demonstrated that testosterone may influence components of metabolic flexibility as 6 months of transdermal testosterone treatment in aging men with low–normal bioavailable testosterone levels increased lipid oxidation and decreased glucose oxidation during the fasting state.
  • Decreased lipid oxidation coupled with diet-induced chronic FA elevation is linked to increased accumulation of myocellular lipid, in particular diacylglycerol and/or ceramide in myocytes
  • In the Chang human adult liver cell line, insulin receptor mRNA expression was significantly increased following exposure to testosterone
  • Testosterone deprivation via castration of male rats led to decreased expression of Glut4 in liver tissue, as well as adipose and muscle
  • oestrogen was found to increase the expression of insulin receptors in insulin-resistant HepG2 human liver cell line
  • FFA decrease hepatic insulin binding and extraction, increase hepatic gluconeogenesis and increase hepatic insulin resistance.
  • Only one, albeit large-scale, population-based cross-sectional study reports an association between low serum testosterone concentrations and hepatic steatosis in men (Völzke et al. 2010)
  • This suggests that testosterone may confer some of its beneficial effects on hepatic lipid metabolism via conversion to E2 and subsequent activation of ERα.
  • hypogonadal men exhibiting a reduced lean body mass and an increased fat mass, abdominal or central obesity
  • visceral adipose tissue was inversely correlated with bioavailable testosterone
  • there was no change in visceral fat mass in aged men with low testosterone levels following 6 months of transdermal TRT, yet subcutaneous fat mass was significantly reduced in both the thigh and the abdominal areas when analysed by MRI (Frederiksen et al. 2012b)
  • ADT of prostate cancer patients increased both visceral and subcutaneous abdominal fat in a 12-month prospective observational study (Hamilton et al. 2011)
  • Catecholamines are the major lipolysis regulating hormones in man and regulate adipocyte lipolysis through activation of adenylate cyclase to produce cAMP
  • deficiency of androgen action decreases lipolysis and is primarily responsible for the induction of obesity (Yanase et al. 2008)
  • may be some regional differences in the action of testosterone on subcutaneous and visceral adipose function
  • proinflammatory adipocytokines IL1, IL6 and TNFα are increased in obesity with a downstream effect that stimulates liver production of CRP
  • observational evidence suggests that IL1β, IL6, TNFα and CRP are inversely associated with serum testosterone levels in patients
  • TRT has been reported to significantly reduce these proinflammatory mediators
  • This suggests a role for AR in the metabolic actions of testosterone on fat accumulation and adipose tissue inflammatory response
  • testosterone treatment may have beneficial effects on preventing the pathogenesis of obesity by inhibiting adipogenesis, decreasing triglyceride uptake and storage, increasing lipolysis, influencing lipoprotein content and function and may directly reduce fat mass and increase muscle mass
  • Early interventional studies suggest that TRT in hypogonadal men with T2DM and/or MetS has beneficial effects on lipids, adiposity and parameters of insulin sensitivity and glucose control
  • Evidence that whole-body insulin sensitivity is reduced in testosterone deficiency and increases with testosterone replacement supports a key role of this hormone in glucose and lipid metabolism
  • Impaired insulin sensitivity in these three tissues is characterised by defects in insulin-stimulated glucose transport activity, in particular into skeletal muscle, impaired insulin-mediated inhibition of hepatic glucose production and stimulation of glycogen synthesis in liver, and a reduced ability of insulin to inhibit lipolysis in adipose tissue
  • Nathan Goodyear on 08 May 13
     
    Great review of the Hypogonadal-obesity-adipocytokine hypothesis.
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