Age, obesity and inflammation at baseline predict the effects of testosterone administration on the metabolic syndrome

The Anti-Inflammatory Effects of Testosterone

Low plasma testosterone (T) levels correlated with metabolic syndrome, cardiovascular diseases, and increased mortality risk. T exerts a significant effect on the regulation of adipose tissue accumulation, and in the glucose and lipids metabolism. Adipocytes are the primary source of the most important adipokines responsible for inflammation and chronic diseases. This review aims to analyze the possible effect of T on the regulation of the proinflammatory cytokines secretion.

A systematic literature search on MEDLINE, Google Scholar, and Cochrane using the combination of the following keywords: “testosterone” with “inflammation,” “cytokines,” “adiponectin, CRP, IL-1B, IL-6, TNFα, leptin” was conducted. Sixteen articles related to the effect of low T level and 18 to the effect of T therapy on proinflammatory cytokine were found.

T exerts a significant inhibitory effect on adipose tissue formation and the expression of various adipocytokines, such as leptin, TNF-α, IL-6, IL-1, and is positively correlated with adiponectin level, whereas a low T level is correlated with increased expression of markers of inflammation. Further studies are necessary to investigate the role of T, integrated with weight loss and physical activity, on its action on the mechanisms of production and regulation of proinflammatory cytokines.

Effects of five-year treatment with testosterone undecanoate on metabolic and hormonal parameters in ageing men with metabolic syndrome

Metabolic and hormonal modifications after long-term testosterone (T) treatment have never been investigated. 20 hypogonadal men (mean T = 241 ng/dL-8.3 nmol/L) with metabolic syndrome (MS, mean age 58) were treated with T-undecanoate injections every 12 weeks for 60 months. 20 matched subjects in whom T was unaccepted or contraindicated served as controls. Primary endpoints were variations from baseline of metabolic and hormonal parameters. In T-group, significant reductions in waist circumference (-9.6 ± 3.8 cm, P < 0.0001), body weight (-15 ± 2.8 Kg, P < 0.0001), and glycosylated hemoglobin (-1.6  ±  0.5%, P < 0.0001) occurred, along with improvements in insulin sensitivity (HOMA-I; -2.8  ±  0.6, P < 0.0001), lipid profile (total/HDL-cholesterol ratio -2.9 ± 1.5, P < 0.0001), systolic and diastolic blood pressure (-23 ± 10 and -16 ± 8 mm Hg, P < 0.0001, resp.), and neck and lumbar T-scores (+0.5 ± 0.15 gr/cm(2), P < 0.0001; +0.7 ± 0.8, P < 0.0001, resp.). Also, serum vitamin D (+14.0 ± 1.3 ng/mL, P < 0.01), TSH (- 0.9 ± 0.3 mUI/mL, P < 0.01), GH (0.74 ± 0.2 ng/mL, P < 0.0001), and IGF1 (105 ± 11 ng/mL, P < 0.01) levels changed in T-group but not in controls. Normalization of T levels in men with MS improved obesity, glycemic control, blood pressure, lipid profile, and bone mineral density compared with controls. Amelioration in hormonal parameters, that is, vitamin D, growth hormone, and thyrotropin plasma levels, were reported.

Testosterone as potential effective therapy in treatment of obesity in men with testosterone deficiency: a review

OBJECTIVE

Obesity negatively affects human health. Limiting food intake, while producing some weight loss, results in reduction of lean body mass. Combined with moderate exercise it produces significant weight loss, maintains lean body mass and improves insulin sensitivity, but appears difficult to adhere to. Bariatric surgery is clinically effective for severely obese individuals compared with non-surgical interventions, but has limitations. Clinical and pre-clinical studies have implicated a role for testosterone (T) in the patho-physiology of obesity.

EVIDENCE ACQUISITION AND SYNTHESIS

A literature search in PubMed on the role of T in counteracting obesity and its complications.

RESULTS

Obesity per se impairs testicular T biosynthesis. Furthermore, lower-than-normal T levels increase accumulation of fat depots, particularly abdominal (visceral) fat. This fat distribution is associated with development of metabolic syndrome (MetS) and its sequels, namely type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). T treatment reverses fat accumulation with significant improvement in lean body mass, insulin sensitivity and biochemical profiles of cardiovascular risk. The contribution of T to combating obesity in hypogonadal men remains largely unknown to medical professionals managing patients with obesity and metabolic syndrome. Many physicians associate T treatment in men with risks for prostate malignancy and CVD. These beliefs are not supported by recent insights.

CONCLUSION

While overall treatment of obesity is unsuccessful, T treatment of hypogonadal men may be effective, also because it improves mood, energy, reduces fatigue and may motivate men to adhere to diet and exercise regimens designed to combat obesity.