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Nathan Goodyear

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

  • 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)
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  • 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
       
      Interesting that the effect of progesterone metabolites were found to be independent from ER status, age, and pre/post menopause
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    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

The effects of creatine supplementation o... [Eur J Appl Physiol. 2004] - PubMed - NCBI - 0 views

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    phosphocreatine helps to maintains muscular performance.  This appears to be an early benefit.  The question is does this help in prolonged performance requirements.
Nathan Goodyear

Prostate cancer risk in testoster... [J Steroid Biochem Mol Biol. 2006] - PubMed - NCBI - 0 views

  • In hypogonadal men who were candidates for testosterone therapy, a 14% incidence of occult cancer was found
  • Data from all published prospective studies on circulating level of total and free testosterone do not support the hypothesis that high levels of circulating androgens are associated with an increased risk of prostate cancer
  • Indeed, high-grade prostate cancer has been associated with low plasma level of testosterone.
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    testosterone therapy does not increase prostate cancer.
Nathan Goodyear

Neuroendocrine disorders after... [J Neurol Neurosurg Psychiatry. 2008] - PubMed - NCBI - 0 views

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    The majority of people with PTHP after TBI remain undiagnosed.  The current thought, is that 25% of those with TBI have at least one pituitary hormone deficiency.  It does not have to be total pituitary failure.  Deficiencies can be isolated.
Nathan Goodyear

Hypopituitarism after traumatic brain injury - 0 views

  • PTHP is observed in about 40% of patients with a history of TBI
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    post-traumatic hypopituitarism is found in 40% of those with TBI.  The severity does correlate with the increased likelihood of developing PTHP.  Isolated deficiencies have been found in PTHP.
Nathan Goodyear

The Neurosteroid Allopregnanolone Promotes Proliferation of Rodent and Human Neural Pro... - 0 views

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    allopregnanolone increases human neural stem cells. Not only does allopregnanolone reduce inflammation, it plays a role in neurogenesis and thus recovery.
Nathan Goodyear

ScienceDirect.com - Nutrition - Vitamin C status and perception of effort during exerci... - 0 views

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    A very small study, but vitamin C shown to reduce fatigue, perception of fatigue and reduced heart rate.  This has implications in improving athletic performance.  The question, what does high dose vitamin C due for fatigue, heart rate, and athletic performance.
Nathan Goodyear

Late-night and low-dose dexamethasone-suppressed cortisol in saliva and serum for the d... - 1 views

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    diagnostic accuracy again proven for salivary cortisol. So why does BCBS consider this experimental?  Maybe they just don't read research.
Nathan Goodyear

Breast Cancer and the Environment: A Life Course Approach - Institute of Medicine - 0 views

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    Is breast cancer a product of the environment?  Not totally, but the environment does play a role and the IOM discuss the current knowledge on the environment and breast cancer
Nathan Goodyear

Targeting gut microbiota in obesity: effects of prebiotics and probiotics : Article : N... - 0 views

  • gut microbes have a role in the host's metabolic homeostasis
  • lipopolysaccharide (LPS)
  • Associations between circulating LPS level, consumption of a high-fat diet and the presence of obesity and type 2 diabetes mellitus have been confirmed in humans
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  • associations have been proposed between high-fat diet, metabolic endotoxemia and levels of inflammatory markers (TLRs and SOCS3) in mononuclear cells
  • A link between energy intake (high-fat diet) and metabolic endotoxemia has also been described
  • high-fat diet induces metabolic endotoxemia in healthy individuals.
  • metabolic endotoxemia is associated with systemic and adipose tissue inflammation in pregnant women with obesity
  • A growing amount of evidence indicates that changes in the integrity of the intestinal barrier occur both in the proximal and the distal part of the gut, which can contribute to the entrance of LPS into the systemic circulation
  • intestinal endocannabinoid system
  • The low-grade systemic inflammation that characterizes the obese phenotype is controlled by peptides that are produced in the gut. These peptides are influenced by the presence or absence of the gut microbiota
  • these findings suggest that the gut microbiota modulates the biological systems that regulate the availability of nutrients, energy storage, fat mass development and inflammation in the host, which are all components of the obese phenotype
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    good look of how the the gut health, or lack there of, can influence energy homeostasis and contribute to obesity.  This article points to the presence of LPS playing a role in metabolic endotoxemia.  It does discuss the importance of the microbiota and their possible role in the low-grade systemic inflammation condition that is obesity.
Nathan Goodyear

JCI - Inflammation and insulin resistance - 0 views

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    How does inflammation cause insulin resistance?  This in-depth paper helps to explain the current understanding.   More and more obesity is part of a growing inflammatory epidemic.
Nathan Goodyear

Red Versus White Wine as a Nutriti... [J Womens Health (Larchmt). 2011] - PubMed - NCBI - 0 views

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    red wine does appear to have health benefits over white wine through aromatase inhibition.  Aromatase inhibition reduces estrogen levels.  So, if the breast cancer risk is associated with elevated estrogen, then this would logically reduce the risk.  The exact amount is unknown, but aromatase inhibition is a treatment of those with breast CA.
Nathan Goodyear

Supplementation of Vitamin C Reduces Blood Glucose and Improves Glycosylated Hemoglobin... - 0 views

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    Oral vitamin C shown to reduce fast blood glucose, post meal blood glucose, and HgbA1C.  This study was down with metformin.  Vitamin C was used with metformin in those with type II DM.  This supports the use of vitamin C in blood sugar control.  Vitamin C does not increase blood glucose levels.
Nathan Goodyear

The Journal of Bone & Joint Surgery | Article - 0 views

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    It is no surprise that hyperglycemia is associated with increased hospital stay and post operative infection.  I have seen this in my former population.  Especially in prolapse and incontinence surgeries (which I no longer perform).  However, what is interesting is that 1/3 of the non-diabetics are hyperglycemic.  The preparation of the individual has just as much to do with the successful outcome of the surgery as does the surgery itself.
Nathan Goodyear

Is dehydroepiandrosterone a hormone? - 0 views

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    Great review on dehydroepiandrosterone (DHEA): what it is, what it does, and the literature behind our current understanding.
Nathan Goodyear

JAMA Network | JAMA: The Journal of the American Medical Association | Low-Fat Dietary ... - 0 views

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    The women's health initiative dietary modification trial of almost 50,000 women found no association between a low fat diet and a reduction of colorectal cancer.  Translation: a low fat diet does not lower the risk of colorectal cancer.
Nathan Goodyear

Intense sweetness surpasses cocaine reward. [PLoS One. 2007] - PubMed - NCBI - 0 views

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    Rats that were sensitized to cocaine, preferred artificial sweeteners over that of cocaine. Think about that for a moment.  Does that redefine addiction?
Nathan Goodyear

Low Doses of Lipopolysaccharide and Minimally Oxidized Low-Density Lipoprotei... - 0 views

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    LPS and minimal oxidized LDL have synergistic effects on inflammatory signaling.  Together the two promote inflammatory signaling from macrophages at much lower levels than either one alone.  They do this through macrophage NF-KappaB and AP-1 pathways.  And this resultant inflammation promotes atherosclerosis.  Where does all this start?  our diet and our gut.
Nathan Goodyear

Scleroderma - 8 - Fibroblasts, Systemic Sclerosis, Calcitriol - Life Extension Health C... - 0 views

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    nice review of natural therapies for scleroderma.  Life extensions always does a great job of supporting natural therapies with science.
Nathan Goodyear

Androgens and prostate disease Cooper LA, Page ST - Asian J Androl - 0 views

  • intraprostatic androgens are not concomitantly increased when serum androgen levels are raised.
  • The "saturation model" proposes that the prostate is sensitive to very low concentrations of circulating androgens, but that once maximal AR binding is achieved, which occurs at relatively low concentrations of circulating T, further increases in serum T have little impact
  • men with metastatic prostate cancer given T who had been previously treated with castration had worsening of disease, whereas those without prior castration did not
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  • There is little data to support the withholding of T therapy on the basis of concern for precipitating prostate cancer.
  • Both intervention data and physiology studies point to minimal effects on the prostate gland when serum T levels are increased to the mid-normal range with T therapy
  • an individualized care plan to assess the possible risks and benefits of T therapy for each patient is critical to optimizing the use of androgens in male health.
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    Nice review of the mixed data on Testosterone and Prostate disease. It is clear that Testosterone does not precipitate prostate cancer.  The intraprostatic hormone milieu likely is different than that present in the serum.  No surprise there.  5alpha reductase decreases prostate volume, PSA, and low-grade prostate cancer, but actually increases aggressive prostate cancer. Supraphysiologic doping in young men associated with no increase in prostate disease. PSA no longer to be followed in men < 55.  Mortality rate not changed.  PSA change of 1.4 ng/ml is appropriate for additional prostate evaluation.  Testosterone therapy on average increased 0.5 ng/ml. Still, no mention of aromatase activity in this article.  Why is it that hormone sensitive disease in men is only with regards to androgens and women estrogen.
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