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Nathan Goodyear

Fifty- two-Week Treatment With Diet and Exercise Plus Transdermal Testosterone Reverses the Metabolic Syndrome and Improves Glycemic Control in Men With Newly Diagnosed Type 2 Diabetes and Subnormal Plasma Testosterone - Heufelder - 2013 - Journal of Andr - 0 views

  • there appears to be a positive correlation between serum testosterone levels and insulin sensitivity in men across the full spectrum of glucose tolerance (Pitteloud et al, 2005), and this relationship is at least partially direct and not fully dependent on (changes in) elements of the MetS
  • supervised D&E alone led to significant improvements in testosterone concentrations, glycemic control, and components of the MetS
  • diet control, exercise, and testosterone supplementation may be beneficial in the management of men with T2D
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  • androgen-deprivation therapy in males with prostatic cancer may be associated with an increased risk for T2D, which may be caused by negative effects on insulin sensitivity
  • insulin sensitivity, measured by HOMA, improved in both groups and with a significantly greater degree when testosterone was added to supervised D&E
  • Fasting insulin concentrations, a good representative of insulin sensitivity, did show a significant correlation with changes in circulating androgen levels, an observation in support of Pitteloud et al (2005), who showed a direct relationship between insulin sensitivity and circulating testosterone concentrations using the hyper-insulinemic euglycemic clamp technique
  • 52 weeks of testosterone treatment also significantly improved circulation levels of adiponectin and hsCRP, key serum markers of insulin sensitivity and hepatic steatosis
  • The changes in both adiponectin and hsCRP were significantly correlated with the therapy-induced changes in bioavailable testosterone
  • a negative correlation was found between hsCRP levels and bioavailable testosterone
  • serum PSA concentrations did not differ between the 2 treatment groups, indicating that short-term testosterone administration appears to be acceptably safe
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    Study of men with metabolic syndrome and type II Diabetes finds that diet and exercise alone improved glucose control and metabolic syndrome components by 31%.  The addition of Testosterone therapy increased this % to 81%.
Nathan Goodyear

Lipoprotein(a) as a cardiovascular risk factor: current status - 0 views

  • Lipoprotein(a) is a plasma lipoprotein consisting of a cholesterol-rich LDL particle with one molecule of apolipoprotein B100 and an additional protein, apolipoprotein(a)
  • Elevated Lp(a) levels can potentially increase the risk of CVD (i) via prothrombotic/anti-fibrinolytic effects as apolipoprotein(a) possesses structural homology with plasminogen and plasmin but has no fibrinolytic activity and (ii) via accelerated atherogenesis as a result of intimal deposition of Lp(a) cholesterol, or both
  • evidence suggests that apolipoprotein(a) adducts extracellularly and covalently to apolipoprotein B100-containing lipoproteins, predominantly LDL
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  • Lp(a) is relatively refractory to both lifestyle and drug intervention.
  • Other agents reported to decrease Lp(a) to a minor degree (<10%) include aspirin, l-carnitine, ascorbic acid combined with l-lysine, calcium antagonists, angiotensin-converting enzyme inhibitors, androgens, oestrogen, and its replacements (e.g. tibolone), anti-estrogens (e.g. tamoxifen), and thyroxine replacement in hypothyroid subjects
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    full article on the previously posted abstract on Lp(a).  
Nathan Goodyear

Differential Effects of Dehydroepiandrosterone and Testosterone in Prostate and Colon Cancer Cell Apoptosis: The Role of Nerve Growth Factor (NGF) Receptors: Endocrinology: Vol 154, No 7 - 0 views

  • Several studies indicate that DHEA may enhance cancer-promoting activities in several prostate cancer cell lines acting as agonist or antagonist for the intracellular AR
  • the estrogenic metabolites of DHEA, 5a-androstane-3b, 17b-diol (3b-Adiol) and E2 bind to estrogen receptors but not to AR
  • no specific receptor has been identified for DHEA
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  • Different members of neurotrophins are expressed during cancer progression, suggesting their involvement in cell proliferation, anoikis protection, and malignancy
  • Regulation of the apoptotic machinery in prostate and colon cancer cells by testosterone occurs rapidly and is initiated at the plasma membrane level through specific membrane-binding sites not involving the classical cytoplasmic AR
  • testosterone exerts potent regulatory effects on prostate and colon cancer cell apoptosis
  • Testosterone increased cell death in a dose-dependent manner
  • testosterone antagonizes the prosurvival effects of DHEA in neuronal cells, blocking its binding to NGF receptors
  • treatment of cells with DHEA exerted a strong antiapoptotic effect,
  • Androgens hold a central role in prostate and colon cancer biology
  • elevated levels of DHEA or its sulfate ester DHEA-sulfate in young adults are associated to low incidence of androgen-dependent tumors
  • DHEA may play a protective role in young prostate
  • The decline of DHEA with aging may contribute to prostate cancer progression associated with advanced age
  • DHEA is an effective antiapoptotic factor, reversing the serum deprivation-induced apoptosis in prostate cancer cells (DU145 and LNCaP cell lines) as well as in colon cancer cells
  • NGF appears to exert similar antiapoptotic actions in both prostate and color cancer cells
  • exposure of prostate DU145 and colon Caco2 cancer cells to testosterone totally blocked the protective effects of both DHEA and NGF. These findings suggest that testosterone acts as an antagonist of DHEA and NGF
  • These findings support the hypothesis that testosterone may inhibit cancer cell growth by antagonizing the proliferative, antiapoptotic effects of endogenous factors, such as DHEA or NGF, in the case of prostate and colon cancer cells
  • intratumor hormonal microenvironment may play a critical role in tumor progression.
  • The paracrine interactions of androgens with locally produced NGF may define tumor cell fate
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    Full article of previously posted abstract.  Cancers are unique.  Not all cancers are alike.  Whether they are tissue specific or not, cancers are unique.  This article describes the uniqueness of DHEA and Testosterone cancer, with particular attention to colon.
Nathan Goodyear

Exercise-Associated Muscle Cramps - 0 views

  • athletes who develop EAMC often ingest similar amounts of fluid during exercise as do their noncramping counterparts
  • Oral fluid ingestion may be ineffective, and intravenous fluid may provide a faster delivery for athletes suffering from acute EAMC
  • It is interesting that stretching the affected muscle almost immediately relieves EAMC
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  • Stretching, the primary treatment for acute EAMC
  • National Athletic Trainers’ Association recommends that athletes prone to muscle cramping add 0.3 to 0.7 g/L of salt to their drinks to stave off muscle cramps
  • Others have recommended adding higher amounts of sodium (about 3.0 to 6.0 g/L) to sports drinks based on the frequency of EAMC
  • intravenous infusion of fluids removes this delay, and it has been used to aid athletes who develop acute EAMC
  • maintaining hydration and adequate electrolyte levels is a good prevention strategy for individuals susceptible to EAMC
  • Fluid volumes of 1.8 L per hour have been well tolerated by tennis athletes who are susceptible to EAMC
  • Monitoring an athlete’s body weight is an easy method of ensuring adequate fluid replacement and individualizes each athlete’s fluid needs
  • the National Athletic Trainers’ Association and the American College of Sports Medicine recommend a volume of fluid that allows for less than a 2% body weight reduction
  • Endurance training may also serve as an effective means of preventing EAMC by expanding plasma volume and the extracellular fluid compartment15 and delaying neuromuscular fatigue
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    Exercise associated muscle cramps or EAMC is not worked out.  The theories include dehydration, mineral/electrolyte deficiencies, and neuromuscular activity.
Nathan Goodyear

Androgen Therapy Improves Insulin Sensitivity and Decreases Leptin Level in Healthy Adult Men With Low Plasma Total Testosterone - 0 views

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    Three month study of men with low T, found that Testosterone therapy improved insulin sensitivity and reduced leptin levels.  The group of men here were described as "healthy, non-obese men".   Remember, low T is a biomarker of poor health in men, so the authors statement about the study group is inaccurate.  This also points to a relatively quick metabolic effect by Testosterone and a direct effect on insulin receptor effect and adipocyte leptin release.
Nathan Goodyear

Testosterone level in men with type 2 diabetes mellitus and related metabolic effects: A review of current evidence - 0 views

  • defined by consistent symptoms and signs of androgen deficiency, and an unequivocally low serum testosterone level
  • the threshold serum testosterone level below which adverse clinical outcomes occur in the general population is not known
  • most population-based studies use the serum testosterone level corresponding to the lower limit, quoted from 8.7 to 12.7 nmol/L, of the normal range for young Caucasian men as the threshold
    • Nathan Goodyear
       
      this equals 251 to 366 in serum Total Testosterone
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  • Researchers tried to examine whether serum total or free testosterone would be a better/more reliable choice when studying the effect of testosterone. The results were mixed. Some reported significant associations of both serum total and free testosterone level with clinical parameters25, whereas others reported that only serum free testosterone26 or only serum total testosterone6 showed significant associations.
  • −0.124 nmol/L/year in serum total testosterone
    • Nathan Goodyear
       
      this equates to a 4 ng/dl decline annually in total Testosterone.
  • In experimental studies, androgen receptor knockout mice developed significant insulin resistance rapidly
  • In mouse models, testosterone promoted differentiation of pluripotent stem cells to the myogenic lineage
  • testosterone decreased insulin resistance by enhancing catecholamine induced lipolysis in vitro, and reducing lipoprotein lipase activity and triglyceride uptake in human abdominal tissue in vivo
  • by promoting lipolysis and myogenesis, testosterone might lead to improved insulin resistance
  • testosterone regulated skeletal muscle genes involved in glucose metabolism that led to decreased systemic insulin resistance
  • In the liver, hepatic androgen receptor signaling inhibited development of insulin resistance in mice
  • independent and inverse association of testosterone with hepatic steatosis shown in a cross-sectional study carried out in humans
  • In short, androgen improves insulin resistance by changing body composition and reducing body fat.
  • Although a low serum testosterone level could contribute to the development of obesity and type 2 diabetes through changes in body composition, obesity might also alter the metabolism of testosterone
  • In obese men, the peripheral conversion from testosterone to estrogen could attenuate the amplitude of luteinizing hormone pulses and centrally inhibit testosterone production
  • leptin, an adipokine, has been shown to be inversely correlated with serum testosterone level in men
  • Leydig cells expressed leptin receptors and leptin has been shown to inhibit testosterone secretion, suggesting a role of obesity and leptin in the pathogenesis of low testosterone
    • Nathan Goodyear
       
      So what is "unequivocal"?
  • Baltimore Longitudinal Study of Aging (BLSA) cohort made up of 3,565 middle-class, mostly Caucasian men from the USA, the incidence of low serum total testosterone increased from approximately 20% of men aged over 60 years, 30% over 70 years, to 50% over 80 years-of-age
  • 30–44% sex hormone binding globulin (SHBG)-bound testosterone and 54–68% albumin-bound testosterone
  • As the binding of testosterone to albumin is non-specific and therefore not tight, the sum of free and albumin-bound testosterone is named bioavailable testosterone, which reflects the hormone available at the cellular level
  • Serum total testosterone is composed of 0.5–3.0% of free testosterone unbound to plasma proteins
  • alterations in SHBG concentration might affect total serum testosterone level without altering free or bioavailable testosterone
  • listed in Table​T
  • A significant, independent and longitudinal effect of age on testosterone has been observed with an average change of −0.124 nmol/L/year in serum total testosterone28. The same trend has been shown in Europe and Australia
  • Asian men residing in HK and Japan, but not those living in the USA, had 20% higher serum total testosterone than in Caucasians living in the USA, as shown in a large multinational observational prospective cohort of the Osteoporotic Fractures in Men Study
  • subjects with chronic diseases consistently had a 10–15% lower level compared with age-matched healthy subjects
  • In Caucasians, the mean serum total testosterone level for men in large epidemiological studies has been reported to range from 15.1 to 16.6 nmol/L
  • Asians, higher values, ranging from 18.1 to 19.1 nmol/L, were seen in Korea and Japan
  • Chinese middle-aged men reported a similar mean serum testosterone level of 17.1 nmol/L in 179 men who had a family history of type 2 diabetes and 17.8 nmol/L in 128 men who had no family history of type 2 diabetes
  • The reduction of total testosterone was 0.4% per year in both groups
  • HK involving a cohort of 1,489 community-dwelling men with a mean age of 72 years, a mean serum total testosterone of 19.0 nmol/L was reported
  • pro-inflammatory factors, such as tumor necrosis factor-α in the testes, could locally inhibit testosterone biosynthesis in Leydig cells47, and testosterone treatment in men was shown to reduce the level of tumor necrosis factor-α
  • In Asians, a genetic deletion polymorphism of uridine diphosphate-glucuronosyltransferase UGT2B17 was associated with reduced androgen glucuronidation. This resulted in higher level of active androgen in Asians as compared to Caucasians, as Caucasians' androgen would be glucuronidated into inactive forms faster.
  • Compared with Caucasians, the frequency of this deletion polymorphism of UGT2B17 was 22-fold higher in Asian subjects
  • Other researchers have suggested that environmental, but not genetic, factors influenced serum total testosterone
  • The basal and ligand-induced activity of the AR is inversely associated with the length of the CAG repeat chain
  • In the European Male Aging Study, increased estrogen/androgen ratio in association with longer AR CAG repeat was observed
  • a smaller number of AR CAG repeat had been shown to be associated with benign prostate hypertrophy and faster prostate growth during testosterone treatment
  • In India, men with CAG ≤19 had increased risk of prostate cancer
  • the odds of having a short CAG repeat (≤17) were substantially higher in patients with lymph node-positive prostate cancer than in those with lymph node-negative disease or in the general population
  • assessing the polymorphism at the AR level could be a potential tool towards individualized assessment and treatment of hypogonadism.
  • In elderly men, there was reduced testicular response to gonadotropins with suppressed and altered pulsatility of the hypothalamic pulse generator
  • a significant, independent and longitudinal effect of age on serum total testosterone level had been observed
  • A significant graded inverse association between serum testosterone level and insulin levels independent of age has also been reported in Caucasian men
  • Low testosterone is commonly associated with a high prevalence of MES
  • most studies showed that changes in serum testosterone level led to changes in body composition, insulin resistance and the presence of MES, the reverse might also be possible
  • MES predicted a 2.6-fold increased risk of development of low serum testosterone level independent of age, smoking and other potential confounders
  • Other prospective studies have shown that development of MES accelerated the age-related decline in serum testosterone level
  • In men with type 2 diabetes, changes in serum testosterone level over time correlated inversely with changes in insulin resistance
  • weight loss by either diet control or bariatric surgery led to a substantial increase in total testosterone, especially in morbidly obese men, and the rise in serum testosterone level was proportional to the amount of weight lost
  • To date, published clinical trials are small, of short duration and often used pharmacological, not physiological, doses of testosterone
  • In the population-based Osteoporotic Fractures in Men Study cohort from Sweden, men in the highest quartile of serum testosterone level had the lowest risk of cardiovascular events compared with men in the other three quartiles (hazard ratio [HR] 0.70
  • low serum total testosterone was associated with a significant fourfold higher risk of cardiovascular events when comparing men from the lowest testosterone tertile with those in the highest tertile
  • Shores et al. were the first to report that low serum testosterone level, including both serum total and free testosterone, was associated with increased mortality
  • low serum total testosterone predicted increased risk of cardiovascular mortality with a HR of 1.38
  • low serum total testosterone increased all-cause (HR 1.35, 95% CI 1.13–1.62, P < 0.001) and cardiovascular mortality (HR 1.25
  • European Association for the Study of Diabetes 2013 suggested there was an inverse relationship between serum testosterone level and acute myocardial infarction
  • Diabetic men in the highest quartile of serum total testosterone had a significantly reduced risk of acute MI when compared with those in the lower quartiles
  • serum total testosterone level in the middle two quartiles at baseline predicted reduced incidence of death compared with having the highest and lowest levels
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    Nice review of Testosterone levels and some of the evidence linking Diabetes with low T.  However, the conclusion by the authors regarding what is causing the low T in men with Diabetes is baffling.  The literature does not point to one cause, it is clearly multifactorial--obesity, inflammation, high aromatase activity...I would suggest the authors continue their readings in the manner.
Nathan Goodyear

In Older Men an Optimal Plasma Testosterone Is Associated With Reduced All-Cause Mortality and Higher Dihydrotestosterone With Reduced Ischemic Heart Disease Mortality, While Estradiol Levels Do Not Predict Mortality: The Journal of Clinical Endocrinology - 0 views

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    men with Testosterone levels in the middle quintiles had the lowest risk of death compared to low and high quintile levels.  
Nathan Goodyear

A Prospective Study of Plasma Ferritin Level and Incident Diabetes - 0 views

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    Ferritin more than just associated with diabetes; appears to play a role in the development of diabetes.
Nathan Goodyear

The Effect of Simvastatin on Plasma Steroid Hormone Levels in Metformin-Treated Women with Non-Classic Congenital Adrenal Hyperplasia. - PubMed - NCBI - 0 views

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    Statins are known to reduce Testosterone in men; new study finds statins reduce all androgens in women.
Nathan Goodyear

Stuck at the bench: Potential natural neuroprotective compounds for concussion - 0 views

  • Long-chain polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are highly enriched in neuronal synaptosomal plasma membranes and vesicles
  • The predominant CNS polyunsaturated fatty acid is DHA
  • effective supplementation and/or increased ingestion of dietary sources rich in EPA and DHA, such as cold-water fish species and fish oil, may help improve a multitude of neuronal functions, including long-term potentiation and cognition.
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  • multiple preclinical studies have suggested that DHA and/or EPA supplementation may have potential benefit through a multitude of diverse, but complementary mechanisms
  • pre-injury dietary supplementation with fish oil effectively reduces post-traumatic elevations in protein oxidation
  • The benefits of pre-traumatic DHA supplementation have not only been independently confirmed,[150] but DHA supplementation has been shown to significantly reduce the number of swollen, disconnected and injured axons when administered following traumatic brain injury.
  • DHA has provided neuroprotection in experimental models of both focal and diffuse traumatic brain injury
  • potential mechanisms of neuroprotection, in addition to DHA and EPA's well-established anti-oxidant and anti-inflammatory properties
  • Despite abundant laboratory evidence supporting its neuroprotective effects in experimental models, the role of dietary DHA and/or EPA supplementation in human neurological diseases remains uncertain
  • Several population-based, observational studies have suggested that increased dietary fish and/or omega-3 polyunsaturated fatty acid consumption may reduce risk for ischemic stroke in several populations
  • Randomized control trials have also demonstrated significant reductions in ischemic stroke recurrence,[217] relative risk for ischemic stroke,[2] and reduced incidence of both symptomatic vasospasm and mortality following subarachnoid hemorrhage
  • Clinical trials in Alzheimer's disease have also been largely ineffective
  • The clinical evidence thus far appears equivocal
  • curcumin has gained much attention from Western researchers for its potential therapeutic benefits in large part due to its potent anti-oxidant[128,194,236] and anti-inflammatory properties
  • Curcumin is highly lipophilic and crosses the blood-brain barrier enabling it to exert a multitude of different established neuroprotective effects
  • in the context of TBI, a series of preclinical studies have suggested that pre-traumatic and post-traumatic curcumin supplementation may bolster the brain's resilience to injury and serve as a valuable therapeutic option
  • Curcumin may confer significant neuroprotection because of its ability to act on multiple deleterious post-traumatic, molecular cascades
  • studies demonstrated that both pre- and post-traumatic curcumin administration resulted in a significant reduction of neuroinflammation via inhibition of the pro-inflammatory molecules interleukin 1β and nuclear factor kappa B (NFκB)
  • no human studies have been conducted with respect to the effects of curcumin administration on the treatment of TBI, subarachnoid or intracranial hemorrhage, epilepsy or stroke
  • studies have demonstrated that resveratrol treatment reduces brain edema and lesion volume, as well as improves neurobehavioral functional performance following TBI
  • green tea consumption or supplementation with its derivatives may bolster cognitive function acutely and may slow cognitive decline
  • At least one population based study, though, did demonstrate that increased green tea consumption was associated with a reduced risk for Parkinson's disease independent of total caffeine intake
  • a randomized, placebo-controlled trial demonstrated that administration of green tea extract and L-theanine, over 16 weeks of treatment, improved indices of memory and brain theta wave activity on electroencephalography, suggesting greater cognitive alertness
  • Other animal studies have also demonstrated that theanine, another important component of green tea extract, exerts a multitude of neuroprotective benefits in experimental models of ischemic stroke,[63,97] Alzheimer's disease,[109] and Parkinson's disease
  • Theanine, like EGCG, contains multiple mechanisms of neuroprotective action including protection from excitotoxic injury[97] and inhibition of inflammation
  • potent anti-oxidant EGCG which is capable of crossing the blood-nerve and blood-brain barrier,
  • Epigallocatechin-3-gallate also displays neuroprotective properties
  • More recent research has suggested that vitamin D supplementation and the prevention of vitamin D deficiency may serve valuable roles in the treatment of TBI and may represents an important and necessary neuroprotective adjuvant for post-TBI progesterone therapy
  • Progesterone is one of the few agents to demonstrate significant reductions in mortality following TBI in human patients in preliminary trials
  • in vitro and in vivo studies have suggested that vitamin D supplementation with progesterone administration may significantly enhance neuroprotection
  • Vitamin D deficiency may increase inflammatory damage and behavioral impairment following experimental injury and attenuate the protective effects of post-traumatic progesterone treatment.[37]
  • emerging evidence has suggested that daily intravenous administration of vitamin E following TBI significantly decreases mortality and improves patient outcomes
  • high dose vitamin C administration following injury stabilized or reduced peri-lesional edema and infarction in the majority of patients receiving post-injury treatment
  • it has been speculated that combined vitamin C and E therapy may potentiate CNS anti-oxidation and act synergistically with regards to neuroprotection
  • one prospective human study has found that combined intake of vitamin C and E displays significant treatment interaction and reduces the risk of stroke
  • Pycnogenol has demonstrated the ability to slow or reduce the pathological processes associated with Alzheimer's disease
  • Pcynogenol administration, in a clinical study of elderly patients, led to improved cognition and reductions in markers of lipid peroxidase
  • One other point of consideration is that in neurodegenerative disease states like Alzheimer's disease and Parkinson's disease, where there are high levels of reactive oxygen species generation, vitamin E can tend to become oxidized itself. For maximal effectiveness and to maintain its anti-oxidant capacity, vitamin E must be given in conjunction with other anti-oxidants like vitamin C or flavonoids
  • These various factors might account for the null effects of alpha-tocopherol supplementation in patients with MCI and Alzheimer's disease
  • preliminary results obtained in a pediatric population have suggested that post-traumatic oral creatine administration (0.4 g/kg) given within four hours of traumatic brain injury and then daily thereafter, may improve both acute and long-term outcomes
  • Acutely, post-traumatic creatine administration seemed to reduce duration of post-traumatic amnesia, length of time spent in the intensive care unit, and duration of intubation
  • At three and six months post-injury, subjects in the creatine treatment group demonstrated improvement on indices of self care, communication abilities, locomotion, sociability, personality or behavior and cognitive function when compared to untreated controls
  • patients in the creatine-treatment group were less likely to experience headaches, dizziness and fatigue over six months of follow-up
  • CNS creatine is derived from both its local biosynthesis from the essential amino acids methionine, glycine and arginine
  • Studies of patients with CNS creatine deficiency and/or murine models with genetic ablation of creatine kinase have consistently demonstrated significant neurological impairment in the absence of proper creatine, phosphocreatine, or creatine kinase function; thus highlighting its functional importance
  • chronic dosing may partially reverse neurological impairments in human CNS creatine deficiency syndromes
  • Several studies have suggested that creatine supplementation may also reduce oxidative DNA damage and brain glutamate levels in Huntington disease patients
  • Another study highlighted that creatine supplementation marginally improved indices of mood and reduced the need for increased dopaminergic therapy in patients with Parkinson's disease
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    great review of natural therapies in the treatment of concussions
Nathan Goodyear

Sources and Significance of Plasma Levels of Catechols and Their Metabolites in Humans - 0 views

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    Good review of the sources and metabolism of catecholamines in the blood.
Nathan Goodyear

Transfusion of Blood and Blood Products: Indications and Complications - - American Family Physician - 0 views

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    Good review of transfusion indications and complications
Nathan Goodyear

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

  • 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
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  • 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
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    Great review on RAS in cancer.
Nathan Goodyear

Delayed-Onset Hemolytic Anemia in Patients with Travel-Associated Severe Malaria Treated with Artesunate, France, 2011-2013 - Volume 21, Number 5-May 2015 - Emerging Infectious Disease journal - CDC - 0 views

  • delayed hemolytic events occur in ≈20% of patients with severe imported malaria, and 60% of these patients require blood transfusion
  • Delayed-onset anemia (herein referred to as postartesunate delayed-onset hemolysis [PADH] pattern of anemia) has been observed to occur 2–3 weeks after initiation of IV artesunate
  • The mechanism of this anemia is hemolytic, as demonstrated by high serum lactate dehydrogenase (LDH) and low plasma haptoglobin levels
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  • this side effect is associated with artesunate
  • PADH occurred in 27% of patients in this study, but it was rarely associated with severe anemia and was never fatal
  • median delayed drop in hemoglobin levels was 1.3 g/dL
  • This transfusion rate (<5%) is markedly lower than that previously reported for patients with severe imported malaria and delayed-onset anemia (≈60%)
  • Side effects of artesunate frequently include gastrointestinal disturbances, neutropenia (1.3%), reticulocytopenia (0.6%), and elevated liver enzymes (1.1%)
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    artesunate
Nathan Goodyear

Plasma prolactin and breast cancer risk: a meta- analysis | Scientific Reports - 0 views

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    prolactin associated wtih ER+/PR+
Nathan Goodyear

Plasma 25-hydroxyvitamin D concentration and subsequent risk of total and site specific cancers in Japanese population: large case-cohort study within Japan Public Health Center-based Prospective Study cohort | The BMJ - 0 views

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    New Study from BMJ finds that higher vitamin D levels are associated with a decreased relative risk for total cancer.  The most significant inverse association was found with risk of liver cancer. The study divided the vitamin D levels into quartiles.
Nathan Goodyear

The Pharmacokinetics and Interactions of Ivermectin in Humans-A Mini-review - 0 views

  • This drug is extensively metabolized by human liver microsomes by cytochrome P450
  • cytochrome P-4503A4, converting the drug to at least 10 metabolites
  • its elimination half-life is around a day
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  • second rise in plasma levels (mostly occurring between 6 and 12 h after the dose) suggesting an enterohepatic recycling of the drug
  • Ivermectin is exceptionally potent, with effective dosages levels that are unusually low.
  • the optimal dose of ivermectin is 150 μg/kg, but the frequency of administration is still controversial, ranging from 150 μg/kg once to three times yearly.
  • high lipid solubility of ivermectin, this compound is widely distributed within the body.
  • To interrupt the transmission of onchocerciasis in humans, the combination of ivermectin and doxycycline is highly effective as, in infested patients, the ingestion of the anthelmintic (200 μg/kg, single dose) and the antibacterial (100 mg/kg, daily for 6 weeks)
  • ivermectin interactions with another concurrently administered drugs can occur.
  • This issue becames important, as combination chemotherapy is being used with increasing frequency as resistance to antiparasitic agents is becoming more widespread.
  • haematomatous swellings
  • prothrombin times were significantly above baseline by one week to one month after drug ingestion, suggesting an antagonist effect against vitamin K
  • bleeding disorders were not found in 15,000 patients treated with ivermectin (150 μg/kg)
  • prolonged prothrombin ratios were observed in 148 subjects given ivermectin orally. Although no patients suffered bleeding complications, factor II and VII levels were reduced in most of them, suggesting interference with vitamin K metabolism
  • Ivermectin has a minimal effect on coagulation and concern about mass treatment for this reason appears to be unjustified
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    Review of Ivermectin as an anti-parasitic.
Nathan Goodyear

Anti-helminth compound niclosamide downregulates Wnt Signaling and elicits antitumor responses in tumors with activating APC mutations - 0 views

  • Others have reported that niclosamide inhibits the NF-κB pathway in leukemia cell lines (26) or mTOR signaling in MCF-7 breast cancer cells
  • niclosamide enhances the anti-tumor effect of oxaliplatin
  • In the more rapidly growing tumor (HCT116), a dose of 200 mg/kg of body weight was needed to suppress the tumor growth
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  • however, 100 mg/kg of niclosamide could suppress the growth of the relatively slow-growing tumor (CRC039) to the same level
  • niclosamide was confirmed to inhibit the growth of human CRCs in NOD/SCID mice
  • niclosamide can inhibit Wnt pathway activation in CRC
  • The mechanism of action of the niclosamide in our studies is thought to be through internalization of Fzd1 and downregulation of Wnt pathway intermediaries
  • Recently, Jin et al. (26) reported that niclosamide inhibited the NF-κB pathway and increased reactive oxygen species levels to induce apoptosis in AML cells. In contrast, we did not observe any inhibitory effect of niclosamide on NF-κB signaling in our CRC model
  • oral administration of niclosamide does result in sufficient distribution of the drug into tumor tissue, to prove a prolonged inhibitory effect on Wnt/ß-catenin signaling, resulting in tumor growth inhibition
  • we required higher doses (100 ~ 200 mg/kg body weight) of niclosamide in order to demonstrate significant inhibition of tumor growth in NOD/SCID mice
  • niclosamide concentrations in tumor tissue showed good correlation with those in plasma, suggesting the efficient distribution of niclosamide from blood to tumor tissue
  • we observed downregulation of Dvl2 and ß-catenin cytosolic expression in niclosamide-treated tumor cells in vivo
  • One potential concern for the use of niclosamide as an anticancer therapy is the poor absorption of this drug
  • The Wnt signaling pathway, fundamental to embryonic tissue patterning, is also activated in stem-like cells
  • The canonical Wnt pathway is activated in approximately 80% of sporadic CRC primarily due to mutations in the APC gene
  • recent observations reveal that Wnt ligands or inhibitors may affect the growth and survival of colon cancer cells in spite of the presence of APC or CTNNB1 mutations
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    Niclosamide found to inhibit Wnt/B-catenin signaling pathway, and thus promotion of apoptosis, in colorectal cancer cells in Vivo study.  It was also found to augment chemotherapeutic.
Nathan Goodyear

Oncotarget | Preclinical evaluation of a nanoformulated antihelminthic, niclosamide, in ovarian cancer - 0 views

  • Ovarian cancer is the most lethal gynecologic malignancy in the world
  • paclitaxel represents a breakthrough in the treatment of ovarian cancer, the overall 5-year survival rate of patients with stage III disease is still approximately 40%
  • Targeting cancer stem cells is an emerging concept in cancer therapy
  • ...8 more annotations...
  • Ovarian cancer stem cells play an important role in chemoresistance and cancer recurrence
  • Furthermore, recent studies indicate that niclosamide exhibits anticancer effects against various human cancer cells by acting on multiple cell signaling pathways and inducing mitochondrial uncoupling [16–21]
  • has low systemic bioavailability (~10%) when administered orally, which is beneficial for treating local parasitic infections of the intestines while minimizing systemic exposure
  • The nano-NI demonstrated significantly higher inhibitory effects on sphere formation than the original niclosamide did
  • the nano-NI formulation decreased the metabolic activity of ovarian cancer cells and caused a metabolic shift from oxidative phosphorylation to glycolysis
  • This toxicity evaluation showed that oral nano-NI had no toxic effect on either group of mice in terms of weight, plasma albumin levels, and blood cell counts, and revealed no adverse effects on vital organ function in the rodents, which suggests that nano-NI is safe for animals
  • niclosamide inhibits tumor cell growth by interrupting multiple pathways (Wnt, Notch, STAT3, NF-κB, and mTORc1) and the generation of reactive oxygen species in several cancer cells
  • The current standard therapy for ovarian cancer includes taxanes and platinum-based chemotherapy after cytoreductive surgery. Among treated patients, nearly 70 to 80% will experience disease recurrence
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    nano-Niclosamide more effective than traditional Niclosamide in in vitro and in vivo ovarian cancer.
Nathan Goodyear

Ivermectin distribution in the plasma and tissues of patients infected with Onchocerca volvulus. - PubMed - NCBI - 0 views

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    Ivermectin at 150 mcg/kg showns fat depot retention.
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