Oral testosterone administration to older relatively hypogonadal men results in an increase in muscle mass and a decrease in body fat.

No abstract

The novel peptide hormone insulin-like peptide 3 (INSL3) is a major secretory product of the Leydig cells of the testis, and in adult men is secreted into the blood, giving rise to circulating concentrations ranging from 0.5 to 2.5 ng/mL. We studied a large randomly recruited cohort of 1183 men from South Australia, comparing serum INSL3 concentrations with age, and a variety of endocrine, cognitive and morphological parameters. While INSL3 concentration declines significantly (p < 0.001) and continuously with age from 1.29 +/- 0.47 ng/mL in young men (age 35-44 years) to 0.79 +/- 0.39 ng/mL in the age group 75-80 years, there is no correlation with testosterone or components of the hypothalamo-pituitary-gonadal (HPG) axis, independent of age, nor with any other parameter measured, including thyroid or prostate status and obesity. For men exhibiting normal follicle stimulating hormone (FSH) and high luteinizing hormone (LH) levels, there was a significant inverse correlation with plasma oestradiol. Unilaterally orchidectomized men had INSL3 values intermediate between intact men and anorchid subjects, and showed inverse correlations (p < 0.001) between INSL3 and FSH or LH concentrations, which were independent of age. Taken together, the data show that INSL3 is an independent measure of Leydig cell function (quality and number), which appears to be independent of acute control via the HPG axis. Its decline with age reflects a decline in the properties of the Leydig cell population only, and emphasizes a gonadal component in the age-related decrease in androgen production.

We investigated whether residential environment characteristics related to food (unhealthful/healthful food sources ratio), walkability and public open spaces (POS; number, median size, greenness and type) were associated with incidence of four cardio-metabolic risk factors (pre-diabetes/diabetes, hypertension, dyslipidaemia, abdominal obesity) in a biomedical cohort (n=3205). Results revealed that the risk of developing pre-diabetes/diabetes was lower for participants in areas with larger POS and greater walkability. Incident abdominal obesity was positively associated with the unhealthful food environment index. No associations were found with hypertension or dyslipidaemia. Results provide new evidence for specific, prospective associations between the built environment and cardio-metabolic risk factors.

The close association of storage LUTS with the metabolic syndrome, and of both storage and voiding LUTS with OSA, suggest that these conditions should be considered in men presenting with LUTS.