Endocrine Abstracts

Evidence supports a protective role for testosterone in men with coronary artery disease (CAD) and in the regulation of cytokine function. This study examined the relationship between serum levels of inflammatory cytokines and testosterone in men with CAD. Serum was collected from 69 men (59+1 years) having >75% occlusion of 1 (n=20), 2 (n=18) or 3 (n=31) coronary arteries. Levels of total testosterone (TT), bioavailable testosterone (BT), tumour necrosis factor-alpha (TNFa...

Background: Testosterone treatment has been shown to increase exercise capacity in men with chronic heart failure but the mechanism of benefit is unclear. The purpose of this study was to examine the acute haemodyamic effects of testosterone in men with heart failure.Methods: Twelve men with stable heart failure (age 62.8 (8.8)years; ejection fraction 30.9 (6.3)% (NR>60%)) were enrolled in a double-blind, placebo-controlled cross-over study. Cardiac o...

Leptin is known to be produced by human pituitary adenomas, and inhibits the proliferation of HP75 cells in vitro. The HP75 cell line is derived from gonadotroph tumour cells from a clinically non-functioning human pituitary adenoma transfected with SV40. The aim of this study was to examine the effects of interleukins (IL) IL1-alpha and IL-6 on growth of HP75 cells and their effects on the growth inhibitory actions of leptin.HP75 cells were plated in 2...

BACKGROUND: We have previously shown that men with coronary artery disease (CAD) have lower serum bioavailable testosterone levels than men with normal coronary arteries and this may have detrimental effects in coronary disease. It has been suggested that low androgen levels in men with CAD could be accounted for by the high prevalence of statin therapy and other factors such as smoking. We investigated the effects of statin therapy and smoking on testosterone in men with CAD....

BACKGROUND: Previous work has demonstrated a relationship between impaired carbohydrate metabolism and low serum levels of androgens in men. Men with diabetes have lower testosterone levels, and administration of physiological doses of testosterone improves glucose tolerance in these men. Men with coronary artery disease (CAD) have lower androgen levels than men with normal coronary arteries. We studied the relationship between testosterone, glucose, hypertension and DM in a p...

Objectives: Testosterone deficiency has been associated with depressive symptoms, which may be improved by replacement therapy. Patients with chronic heart failure have a high prevalence of depression, which is associated with early mortality in these patients. Men with heart failure may also have low plasma levels of testosterone, which could contribute to depressed mood. In a clinical study investigating whether testosterone treatment benefits men with heart failure, patient...

Background: Current evidence suggests that testosterone acts as a vasodilator in several vascular beds. This may have implications for men who are androgen deficient, in whom vascular reactivity may be impaired. We have studied vascular responses in vitro in femoral arteries from testicular feminised mice (Tfm), which lack a functional androgen receptor and are consequently androgen resistant and have reduced circulating levels of testosterone. Methods: Femoral arteries from m...

Chronic heart failure (CHF) is associated with maladaptive and prolonged neurohormonal and pro-inflammatory cytokine activation causing a metabolic shift favouring catabolism, vasodilator incapacity, and loss of skeletal muscle bulk and function. In men, androgens are important determinants of anabolic function and physical strength and also possess anti-inflammatory and vasodilatory properties. We conducted a randomised, double blind, placebo controlled trial of testosterone ...

Testosterone has immune-modulating properties and current in-vitro evidence suggests that testosterone may suppress the expression of the pro-inflammatory cytokines Tumour Necrosis Factor (TNF alpha), interleukin (IL)-1 beta and IL-6 and potentiate the expression of the anti-inflammatory cytokine IL-10. We report a randomised single-blind placebo-controlled crossover study of testosterone replacement (Sustanon 100) versus placebo in 27 men (age 62+-9years) with symptomatic and...

Testicular feminised (Tfm) mice bear an X-linked, single base pair deletion in the gene encoding the classical androgen receptor(1) consequently these animals express a truncated, non-functional form of the receptor protein. Affected animals (XTfmY) are rendered insensitive to actions mediated via this receptor. The Tfm mouse is therefore an excellent model for studying non-genomic testosterone signalling mechanisms. Unfortunately, Tfm mice are also deficient in the...