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Nathan Goodyear

Diurnal cortisol rhythm and fatigue in breast canc... [Psychoneuroendocrinology. 2005] ... - 0 views

www.ncbi.nlm.nih.gov/...15358446

cortisol saliva salivary testing breast cancer

shared by Nathan Goodyear on 26 Jan 11 - No Cached
  • Results suggest a subtle dysregulation in hypothalamic-pituitary-adrenal axis functioning in breast cancer survivors with persistent fatigu
  • Nathan Goodyear on 26 Jan 11
     
    salivary cortisol predictive of fatigue in breast cancer survivors
Nathan Goodyear

Salivary cortisol levels throughout childhood and ... [Pediatr Res. 1995] - PubMed result - 1 views

www.ncbi.nlm.nih.gov/...7596692

salivary cortisol

shared by Nathan Goodyear on 26 Jan 11 - No Cached
  • The measurement of salivary cortisol levels is an attractive way of testing adrenal function in infants and children. It provides a reliable tool for the determination of the physiology and developmental characteristics of cortisol metabolism.
  • Nathan Goodyear on 26 Jan 11
     
    salivary cortisol testing is "attractive and reliable" way to follow cortisol in children and adolescence
Nathan Goodyear

Salivary cortisol and DHEA levels in the Korean po... [Yonsei Med J. 2007] - PubMed result - 0 views

www.ncbi.nlm.nih.gov/...17594144

DHEA cortisol saliva salivary hormone testing

shared by Nathan Goodyear on 13 Jul 11 - No Cached
  • As the cortisol and DHEA levels in saliva reflected those in serum, the measurement of steroid levels in saliva provide a useful and practical tool to evaluate adrenal functions, which are essential for clinical diagnosis.
  • Nathan Goodyear on 13 Jul 11
     
    salivary cortisol and DHEA validated.  
Nathan Goodyear

Salivary cortisol determined by enzyme immunoassay is preferable to serum total cortiso... - 0 views

onlinelibrary.wiley.com/...full

saliva salivary cortisol hormone testing

shared by Nathan Goodyear on 12 Jul 11 - No Cached
  • Nathan Goodyear on 12 Jul 11
     
    salivary testing of cortisol proven to be a better test than blood cortisol.  Published in Clinical Endocrinology, '05.  Salivary cortisol testing is best test to evaluate cortisol levels.
Nathan Goodyear

Sex differences in the adult HPA axis and affectiv... [Brain Res. 2014] - PubMed - NCBI - 0 views

www.ncbi.nlm.nih.gov/...24857958

bisphenol A Bisphenol-A BPA xenoestrogen HPA hypothalamic-pituitary-adrenal EDR endocrine disrupter brain hormone hormones

shared by Nathan Goodyear on 27 May 14 - No Cached
  • Nathan Goodyear on 27 May 14
     
    Animal study finds that Bisphenol A exposure in utero has profound different effects in male offspring versus female offspring.  In the male offspring there appears to be an up regulation of the HPA axis.  The opposite appears true in the female off spring.  Additionally, the receptors are effected differently as well.
Nathan Goodyear

The Benefits and Harms of Systemic Testosterone Therapy in Postmenopausal Women With No... - 0 views

press.endocrine.org/...jc.2014-2262

Testosterone women female hormone hormones menopause

shared by Nathan Goodyear on 06 Feb 15 - No Cached
  • Nathan Goodyear on 06 Feb 15
     
    Only abstract available.  Meta-analysis of Testosterone therapy in post-menopausal women finds significant bias, some improvement in sexual function and cholesterol levels, yet safety and long-term data is significantly lacking.  Take this with studies on endogenous Testosterone in women, significant caution needs to be followed with Testosterone in women. Only abstract available here.
Nathan Goodyear

Effect of Dehydroepiandrosterone Replacement on Insulin Sensitivity and Lipids in Hypoa... - 0 views

diabetes.diabetesjournals.org/...765.long

DHEA hypoadrenia adrenal fatiuge insulin resistance insulin resistance sensitivity

shared by Nathan Goodyear on 03 Aug 14 - No Cached
  • Nathan Goodyear on 03 Aug 14
     
    Study finds 50 mg of DHEA improves insulin sensitivity in Hypoadrenal women.  The authors also found and increase in DHEAS, bioavailable T, androstenedione, and a reduced SHBG, insulin, and glucagon.
Nathan Goodyear

Leptin and Androgens in Male Obesity: Evidence for Leptin Contribution to Reduced Andro... - 0 views

press.endocrine.org/...jcem.84.10.6082

obesity leptin low T low Testosterone Testosterone low T leydig cells LH leutenizing hormone men male hormones hormone

shared by Nathan Goodyear on 04 Sep 14 - No Cached
  • in male obesity basal and LH-stimulated androgen levels are reduced and inversely correlated with circulating leptin
  • functional leptin receptors are present in rodent Leydig cells
  • it is conceivable that in males high leptin concentrations may have a direct inhibitory effect(s) on Leydig cell function.
  • ...18 more annotations...
  • insulin is an important inhibitor of the synthesis of SHBG
  • no correlation between leptin and SHBG levels
  • SHBG reduction in obesity is a minor determinant of lowered androgen levels
  • SHBG can explain only up to 3% of the correlation
  • testicular T de novo production is impaired in obese men and that leptin seems to be the best hormonal predictor of this blunted response to LH stimulation
  • The low basal 17-OH-P levels found in massively obese men are consistent with a global impairment of Leydig cell steroidogenic function in this group of subjects.
  • These findings indicate that obese men have a FM-related defect in the enzymatic conversion of 17-OH-P to T, which is revealed by hCG stimulation.
  • Other studies have investigated the adrenal function in male obesity and have shown that basal cortisol and 17-OH-progesterone levels tend to decrease with the increase in the degree of obesity
  • High E2 can inhibit the expression and activity of the 17,20-lyase and may be responsible for this steroidogenic lesion
  • However, stimulated E2 levels were not higher in the obese than in controls, excluding the fact that the lower androgen response was due to an increased aromatization of T to E2 and that estrogens have a major role in the observed defect of 17,20-lyase activity in obese men.
  • the percentage increase in the 17-OH-progesterone to T molar ratio paralleled the increase in leptin levels of obese men
  • Multiple regression analysis indicated that the best hormonal predictor of the obesity-related reduction in T and FT basal levels and androgen changes after hCG stimulation was serum leptin concentration
  • insulin has no negative influences on androgen production in obese men
  • insulin is known to have stimulatory actions on T production that have been demonstrated in obese and normal weight men (57) and in Leydig cells in culture
  • the negative correlation between insulin and basal T can be partly explained by the inhibitory action of insulin on SHBG production
  • hypogonadal men have higher circulating leptin levels compared with hypogonadal patients under effective androgen substitution therapy
  • The impaired androgen response to LH stimulus was due to a defect in the enzymatic conversion of 17-OH-progesterone to T, which was disclosed by a leptin-related increase in 17-OH-progesterone to T ratio
  • Estrogens, which are inhibitory modulators of LH pulsatility and bioactivity
  • Nathan Goodyear on 04 Sep 14
     
    Leptin appears to be a good marker of low Testosterone.  This study proposes that the mechanism of action is potentially 2 fold: first, a decrease in LH release by leptin (kisspeptin?) and 2nd, a directed decrease in Testosterone production by the leydig cells in the testes.
Nathan Goodyear

The Effect of Simvastatin on Plasma Steroid Hormone Levels in Metformin-Treated Women w... - 0 views

www.ncbi.nlm.nih.gov/...26824284

statins statin therapy Testosterone androgens DHEA hormones women CAH

shared by Nathan Goodyear on 02 Feb 16 - No Cached
  • Nathan Goodyear on 02 Feb 16
     
    Statins are known to reduce Testosterone in men; new study finds statins reduce all androgens in women.
Nathan Goodyear

Renin-angiotensin system and cancer: A review - 0 views

www.oatext.com/system-and-cancer-A-review.php

renin angiotensin system cancer

shared by Nathan Goodyear on 10 Sep 18 - No Cached
  • crucial role of the RAS in the development and maintenance of cancer
  • kidneys, which produce renin in response to decreased arterial pressure, reduced sodium in the distal tubule, or sympathetic nervous system activity via the β-adrenergic receptors
  • Renin is secreted from the juxtaglomerular cells into the bloodstream where it encounters angiotensinogen (AGN), normally produced by the liver
  • ...22 more annotations...
  • Renin catalyses the conversion of AGN to angiotensin I (ATI), which is quickly cleaved by angiotensin converting enzyme (ACE) to form angiotensin II (ATII)
  • ATII triggers the release of aldosterone from the adrenal glands, which stimulates reabsorption of sodium and water and thereby increases blood volume and blood pressure
  • ATII also acts on smooth muscle to cause vasoconstriction of the arterioles
  • ATII promotes the release of antidiuretic hormone from the posterior pituitary gland, which results in water retention and triggers the thirst reflex
  • ability of non-CSCs to ‘de-differentiate’ into CSCs due to epigenetic or environmental factors, which further increases the complexity of tumour biology and treatment
  • efficacy of RAS modulators on cancer in both cancer models and cancer patients
  • A localised (‘paracrine’) RAS mechanism has been identified in many types of cancers, and interruption of the control of the RAS is thought to be the basis for its role in cancer
  • Components of the RAS are expressed by these CSCs, supporting the hypothesis of the presence of a ‘paracrine RAS’ in regulating these CSCs
  • Renin is an enzyme normally released by the kidneys in response to falling arterial pressure
  • a study of GBM demonstrating overexpression of PRR coupled with the observation that inhibition of renin reduces cellular proliferation and promotes apoptosis
  • PRR has been found to be vital for normal Wnt signalling
  • A major focus of PRR research is its relationship with Wnt signalling
  • suggest a crucial role for PRR activation on the proliferation of CSCs, possibly via Wnt/β-catenin signalling, leading to carcinogenesis.
  • Angiotensin converting enzyme (ACE), also known as CD143, is the endothelial-bound peptidase which physiologically converts ATI to ATII
  • ACE is crucial in the regulation of blood pressure, angiogenesis and inflammation
  • results suggest that an overactive ACE promotes cancer growth and progression, and an inhibited or low-activity ACE may have cancer-protective effects
  • When bound to ATII or ATIII it causes vasoconstriction by stimulating the release of vasopressin, reabsorption of water and sodium by promoting secretion of aldosterone and insulin, fibrosis, cellular growth and migration, pro-inflammation, glucose release from the liver, increased plasma triglyceride concentration, and reduced gluconeogenesis
  • ATIIR1 is a G-protein-coupled receptor, with downstream signalling involved in vasodilation, hypertrophy and NF-κB activation leading to TNF-α and PAI-1 expression
  • ATIIR1 has well-documented links with cancer, with one study demonstrating its overexpression in ~20% of breast cancer patients
  • the effect of RAS dysregulation has been associated with increased VEGF expression and angiogenesis in cancers
  • In ovarian and cervical cancer, ATIIR1 overexpression has been shown to be an indicator of tumour invasiveness
  • administration of ATIIR1 blockers (ARBs) have been associated with reduced tumour size, reduction in tumour vascularisation, lower occurrence of metastases, and lower VEGF levels
  • Nathan Goodyear on 10 Sep 18
     
    Great review on RAS in cancer.
Nathan Goodyear

Overtraining Syndrome - 0 views

www.ncbi.nlm.nih.gov/...PMC3435910

overtraining syndrome OTS exercise athletes cortisol adrenals Testosterone Testosterone:Cortisol hormones

shared by Nathan Goodyear on 29 Jan 16 - No Cached
  • Alterations in the HPA and hypothalamic-pituitary-gonadal axes with a resultant decrease in testosterone:cortisol ratios have been implicated in OTS. Proinflammatory cytokines are potent activators of the HPA system, which cause release of corticotropin-releasing hormone, adrenocorticotropic hormone, and cortisol. These cytokines suppress testosterone through central inhibition
  • Some have suggested that a decreased testosterone:cortisol ratio can be diagnostic of NFO and/or OTS. However, the ratio represents the physiologic strain of training rather than the athlete’s maladaption to that stress
  • Cortisol (catabolic and anti-inflammatory) is converted to inactive cortisone by 11β-HSD2
  • ...2 more annotations...
  • A prospective study found a clinically significant increase in overnight urinary cortisol:cortisone ratio during a high training load period in triathletes, who subsequently underperformed and reported fatigue
  • It is proposed that cytokines may inhibit 11β-HSD2 activity and result in relative increases in cortisol and, hence, catabolism
  • Nathan Goodyear on 29 Jan 16
     
    Overtraining syndrome described.
Nathan Goodyear

A relationship in adrenal androgen levels between mothers and their children from a dio... - 0 views

www.sciencedirect.com/...S0048969717316911

EDC endocrine disrupting chemicals hormones endocrine disruptors agent orange DHEA androstenedione

shared by Nathan Goodyear on 04 Oct 17 - No Cached
  • Nathan Goodyear on 04 Oct 17
     
    Endocrine Disrupting Chemicals from 1970 still disrupting hormones today.  Three fold increase in DHEA in 3 year old children via saliva and androstenedione in mothers compared to controls.
Nathan Goodyear

The acute effect of high-dose intravenous vitamin C and other nutrients on blood pressu... - 0 views

www.ncbi.nlm.nih.gov/...PMC4864764

vitamin C IV vitamin C hypertension vitamin B12 blood pressure cardiovascular disease CVD

shared by Nathan Goodyear on 14 Aug 17 - No Cached
  • the reduction in BP within the first 10–20 min may be primarily attributed to a direct vasodilatory physiological effect, described as venodilation
  • BP reduction observed after 70–90 min is likely attributable to pharmacokinetically plausible vitamin C absorption and vasodilation because of nitric oxide release
  • Pharmacokinetic studies of IVC administration observed peak plasma levels within the first 90 min, with plasma levels reaching 13350 μmol/l for 50 g of IVC
  • ...6 more annotations...
  • Essential hypertension, associated with endothelial dysfunction because of an impaired nitric oxide/l-arginine pathway and impaired vasodilation can be restored by vitamin C
  • marked increase in BP response when IVB12 is administered
  • The mean BP increased significantly up to 12–16 mmHg systolic and diastolic independent of the dosage of vitamin B12
  • The production of norepinephrine, which can stimulate angiotensin-II production, which in turn influences BP, has been suggested as a possible mechanism for the increase in BP with IVB12
  • excess norephinephrine levels stimulate the sympathetic nervous system, leading to increased cortisol production, which has also been linked to increases in BP
  • Animal studies have found higher serum levels of norepinephrine (noradrenaline) in the adrenal medulla of rats receiving methylcobalamin (methyl-vitamin B12)
  • Nathan Goodyear on 14 Aug 17
     
    IV vitamin C in mostly normotensive patients (> 30 grams) reduced blood pressure.  Some of the patients were pre-hypertensive. Vitamin B12 increase the blood pressure.
Nathan Goodyear

Tumor regionalization after surgery: Roles of the tumor microenvironment and neutrophil... - 0 views

www.nature.com/...s12276-022-00784-2

TME NETosis metastasis surgery cancer tumor microenvironment

shared by Nathan Goodyear on 20 Apr 23 - No Cached
  • tumor surgery must be carefully considered because the risk of metastasis could be increased by the surgical procedure.
  • NETosis, which is the process of forming neutrophil extracellular traps (NETs)
  • surgery-induced metastasis
  • ...61 more annotations...
  • surgery per se can promote cancer metastasis through a series of local and systemic events
  • surgery results in a serious wound that disrupts the structural barrier preventing the outspreading of cancer cells, change the properties of the cancer cells and stromal cells remaining in the tumor microenvironment, or impairs the host defense systems against cancers
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Key point; add to presentation on surgery and metastasis
  • After the primary tumor is surgically removed, the metastases can start to grow vigorously via neoangiogenesis because the circulating inhibitors disappear
  • infection and inflammation during the postoperative period have been reported to increase the risk of cancer recurrence in patients
  • Surgeons have long suspected that surgery, even if it is a necessary step in cancer treatment, facilitates cancer metastasis
  • Surgery-induced cancer metastasis has been well established in animal models
  • tumor cell dissemination, tumor-favoring immune responses, and neoangiogenesis
  • the surgical resection of primary tumors is beneficial is controversial
  • CTCs abruptly increase just after surgery
  • Even externally palpitating tumors for diagnosis could increase the numbers of CTCs in skin cancer and breast cancer
  • excessive glucocorticoids negatively modulate immune functions
  • immune surveillance against tumors is considered to be impaired by surgical stress
  • In addition to glucocorticoids, during stimulation of the HPA axis, the catecholamine hormones epinephrine and norepinephrine are released from the adrenal medulla
  • NK cell suppression may be attributed to increased levels of catecholamines as well as glucocorticoids
  • In mice bearing a primary tumor, it was observed that the removal of the primary tumor facilitated the growth of highly vascularized metastases
  • primary tumors may secrete angiogenic inhibitors as well as angiogenic activators
  • second phase of tumor recurrence and metastasis, which are newly acquired events, rather than just outcomes of incomplete treatment.
    • Nathan Goodyear
      Nathan Goodyear on 23 Apr 23
       
      Another key point
  • double-edged sword
  • HIF-1 in neutrophils plays a critical role in NETosis and bacteria-killing activity
  • neutrophils play various roles in the initiation and progression of cancer
  • NETosis
  • many inflammatory and neoplastic diseases
  • formation of neutrophil extracellular traps (NETs), which are large extracellular complexes composed of chromatin and cytoplasmic/granular proteins1
  • NETosis has been highlighted as an inflammatory event that promotes cancer metastasis
  • Once activated, neutrophils produce intracellular precursors by using DNA, histones, and granular and cytoplasmic proteins and then spread the mature form of NETs out around themselves
  • A series of these events is called NETosis.
  • neutrophil elastase, myeloperoxidase, cathepsin G, proteinase 3, lactoferrin, gelatinase, lysozyme C, calprotectin, neutrophil defensins, and cathelicidins
  • innate immune response against infection
  • Neutrophils are the most abundant type of granulocytes, comprising 40–70% of all white blood cells
  • two types of NEToses, suicidal (or lytic) NETosis and vital NETosis
  • Suicidal NETosis mainly depends on the production of reactive oxygen species (ROS)
  • Since neutrophils die during this process, it is called suicidal NETosis.
  • vital NETosis
  • vital NETosis occurs independently of ROS production
  • Vital NETosis can be induced by Gram-negative bacteria. LPS
  • NETs are present in a variety of cancers, such as lung cancer, colon cancer, ovarian cancer, and leukemia
  • neutrophils actively undergo NETosis in the tumor microenvironment
  • Hypoxia
  • NETosis plays a pivotal role in noninfectious autoimmune diseases,
  • cytokines
  • tumor-derived proteases
  • tumor exosomes
  • NETosis generally actively progresses in the tumor microenvironment.
  • the proliferative cytokines TGFβ and IL-10 and the angiogenic factor VEGF are representative of neutrophil-derived tissue repair proteins.
  • NETosis is a defense system to protect the body from invading pathogens
  • when neutrophils are excessively stimulated, they produce excess NETs, thereby leading to pathological consequences
  • plasma levels of NETosis markers are elevated after major surgeries
  • local invasion, intravasation into the blood or lymphatic vessels, escape from the immune system, anchoring to capillaries in target organs, extravasation into the organs, transformation from dormant cells to proliferating cells, colonization to micrometastases, and growth to macrometastases
  • NETs promote metastasis at multiple steps
  • NETs loosen the ECM and capillary wall to promote the intravasation of cancer cells
  • NETs and platelets wrap CTCs, which protects them from attack by immune cells and shearing force by blood flow
  • NETs promote the local invasion of cancer cells by degrading the extracellular matrix (ECM)
  • neutrophil elastase, matrix metalloproteinase 9, and cathepsin G
  • NETs also promote the intravasation of cancer cells
  • millions of tumor cells are released into the circulation every day,
  • NETs can wrap up CTCs with platelets
  • β1-integrin plays an important role in the interaction between CTCs and NETs
  • NET-platelet-CTC aggregates.
  • After metastasizing to distant tissues, tumor cells are often found to remain dormant for a period of time and unexpectedly regrow late
  • NETs are believed to participate in the reactivation of dormant cancer cells in metastatic regions
  • NET-associated proteases NE and MMP-9 were found to be responsible for the reactivation of dormant cancer cells
  • Nathan Goodyear on 20 Apr 23
     
    Surgery induced metastasis: it is real and steered by NETosis.
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