Dr. Goodyear

Testosterone therapy in men with low Testosterone was found to improve insulin sensitivity, total cholesterol levels, LDL, Lpa, and sexual performance in men with low T, type II diabetes and/or metabolic syndrome.  There is suggestion that muscle composition was improved as well.

muscle loss, sarcopenia is a significant marker of poor health in men.  This study of 845 men age 45-85 finds that low Testosterone, low vitamin D, low physical activity, smoking, and thin body build are associated with sarcopenia in men.

Study of men and women finds that low free Testosterone, physical activity, and IGF1 is associated with muscle mass in men; no such relationship between sex hormone and muscle mass in women was found.

study of Japanese men finds that low free Testosterone was a predictor of decrease in muscle mass.

Bariatric surgery has a regain of 25-30% of weight loss and a 25% failure to achieve successful weight loss.

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%.

Menopause transition can become a Testosterone dominant phase associated with increased CVD and increased metabolic syndrome.

study of 596 men finds that lower bioavailable Testosterone in those men with Metabolic Syndrome, have an increased cardiovascular mortality in those > 40.

The best marker associated with MetS in older men was low SHBG. Low T, DHT, and cFT were found to be more biomarkers of poor health rather than causal.

Framingham Heart Study finds that low SHBG, not Testosterone was associated with increased risk of metabolic syndrome.

Men with metabolic syndrome found to be associated with higher Estradiol levels.  Thus, Estradiol in "older men", >65 in this study, is associated with metabolic syndrome.

TK-1 is a proliferation biomarker of DNA repair. TK-1 is a nuclear biomarker of cancer prognosis, survival, recurrence and predicts risk of progression of pre-malignant disease.

Upregulation of TK-1 found to be an early event in breast tumor development. This has implications in precancerous tissue and elevations correlate to stage of cancer. TK-1 has also been found to correlate with Cancer recurrence.

Meta-analysis finds that men with low total Testosterone, free Testosterone, and SHBG are more at risk for MetS than those with elevated levels.

Men with metabolic syndrome have lower Testosterone levels when compared to "healthy" individuals.  All men with MetS should have a full androgen analysis performed.  This meta-analysis of 20 studies found Testosterone therapy reduced fasting glucose, HOMA, triglycerides, waist circumference by Testosterone in men with MetS.  This study found that Testosterone therapy increased HDL as well.

low T is associated with increased risk of CV death.  Additionally, Testosterone therapy shown to improve MetS.

In men, 20-94, lower Total Testosterone and SHBG was found to be associated with a higher incidence of metabolic syndrome.  Abstract only.  The greatest association was found with SHBG.

Inflammatory cytokines appear to inhibit hormone production at the levels of the adrenal glands, testes, and ovaries.  This is in addition to suppression at the level of the hypothalamus and pituitary.  One proposed mechanism is via a reduction of sensitivity of the testes to LH.

IL-1beta reduced GNRH and LH production at the level of the Hypothalamus and the Pituitary respectively. What is interesting in this animal model is that greater LH suppression at the pituitary was found to occur in those animals with prior LPS exposure--priming??