High-density lipoprotein response to 5-alpha-dihydrotestosterone and testosterone in Macaca fascicularis: a hormone-responsive primate model for the study of atherosclerosis

Association of Androgenetic Alopecia with Metabolic Syndrome: A Case-control Study on 100 Patients in a Tertiary Care Hospital in South India

BACKGROUND

Androgenetic alopecia (AGA) is the most common cause of hair loss. Although it is a medically benign condition, it can have a significant psychosocial impact on patients. "Metabolic syndrome" (MetS) is a collection of clinical signs that focus on cardiovascular and diabetes-related parameters. Despite the high burden of AGA and MetS in India, specific data on the participants are relatively sparse.

AIM OF THE STUDY

The aim of is to study the association of AGA with MetS and its parameters.

MATERIALS AND METHODS

A case-control study was undertaken in a tertiary care hospital from December 2015 to November 2016 with 100 cases and controls in the age group of 20-50 years. Diagnosis of MetS was based on the National Cholesterol Education Program Adult Treatment Panel III. Independent t-test was used as a test of significance. Categorical data were assessed using Chi-square test of significance. P <0.05 was considered to be significant.

RESULTS

MetS was seen in 53% of cases and 17% of controls (P = 0.001). The mean serum triglyceride level (P = 0.015, P < 0.05), mean systolic blood pressure (P = 0.003, P < 0.05), high-density lipoprotein levels in males (P < 0.001), and waist circumference in males (P = 0.022, P < 0.05) were statistically significant in patients with androgenetic alopecia when compared to healthy controls.

CONCLUSION

A higher prevalence of MetS was noted in androgenic alopecia. Early screening for MetS is beneficial in patients with androgenic alopecia.

Androgenetic alopecia, metabolic syndrome, and insulin resistance: Is there any association? A case-control study

CONTEXT

Although several previous studies have investigated the association of metabolic syndrome (MS) and insulin resistance (IR) with androgenetic alopecia (AGA), the results have been inconsistent.

AIM

We attempted to assess the presence of MS and IR in patients with AGA. This may help to detect if AGA can be considered as a clue for underlying serious systemic diseases.

MATERIALS AND METHODS

One hundred male patients with stages III-VII AGA, in Hamilton-Norwood classification, and 100 normal, gender- and age-matched control subjects were included. Anthropometric measures, blood pressure, fasting glucose, fasting insulin, high-density lipoprotein cholesterol, and triglycerides were measured for the all participants. The presence of MS and IR was evaluated.

RESULTS

There were statistically significant differences regarding mean values of body weight (P < 0.001), height (P = 0.002), waist circumference (P < 0.001), body mass index (P < 0.001), systolic (P < 0.001), and diastolic blood pressure (P < 0.001), fasting glucose (P < 0.001), triglycerides (P < 0.001), high-density lipoprotein cholesterol (P < 0.01), fasting insulin (P = 0.02) and homeostasis model assessment of insulin resistance (P < 0.001) between cases and controls. A statistically significant association was found between AGA and MS (P = 0.002) and between AGA and IR (P < 0.001). Multiple logistic regression analysis revealed that waist circumference (>102 cm) was the most significant risk factor for developing MS. It increased the risk of MS by 1.25-folds (95% CI = 1.10-1.42, P < 0.001).

CONCLUSION

Our results support the recommendation for assessing MS and IR in all young males with stage III or higher AGA. Early intervention is critical to reduce the risk and complications of cardiovascular disease and type 2 diabetes mellitus later in life.

Sex hormones and the changes in adolescent male lipids: longitudinal studies in a biracial cohort

OBJECTIVE

To determine the role of increasing free testosterone and estradiol in pubertal changes in male lipids.

METHODS

We conducted a 3-year, longitudinal, observation study with biannual visits of 251 black and 285 white boys who were 10 to 15 years of age at enrollment. Sex hormones, lipid parameters, and body composition measures were obtained according to a standard protocol. The body mass index (kg/m(2)) was used to characterize obesity.

RESULTS

White boys had higher triglycerides, lower high-density lipoprotein cholesterol (HDL-C), lower apolipoprotein (apo)AI, and higher apoB than black boys. In boys of both races, increased body mass index was associated with increases in triglycerides, low-density lipoprotein cholesterol, apoB and decreases in HDL-C and apoAII. Within this framework, increased free testosterone was associated with increased apoB and decreased HDL-C and apoAI, whereas increased estradiol was associated with increased HDL-C and decreased triglycerides, low-density lipoprotein cholesterol, and apoB.

CONCLUSION

Changes in sex steroid hormones have significant effects on changes in lipid parameters-increasing free testosterone levels has atherogenic effects and increasing estradiol has antiatherogenic effects.

Androgen receptors, 5 alpha-reductase activity and androgen-dependent proliferation of vascular smooth muscle cells

To assess the direct effect of androgen on the development of atherosclerosis, we investigated the effect of androgen and its receptor expression in rat vascular smooth muscle cells (VSMC) isolated from rat aorta. We detected the androgen receptor mRNA in VSMC by reverse transcription of the total RNA coupled with amplification of the resulting cDNA by polymerase chain reaction. Binding studies revealed the presence of a single class of binding sites for testosterone (Kd 7.37 nM, Bmax 10.59 fmol/mg protein) and dihydrotestosterone (DHT; Kd 4.89 nM, Bmax 11.37 fmol/mg protein) in VSMC. Measurement of 5 alpha-reductase activity suggested that testosterone is converted to DHT in VSMC (Km 0.36 microM, Vmax 623 fmol/mg protein/h). Moreover, in the present study, DHT significantly stimulated DNA synthesis of VSMC (120-160% of control). The mitogenic activity of testosterone is much less potent than that of DHT. Considering these results, we concluded that androgen may directly accelerate atherosclerosis by stimulating the proliferation of VSMC.

Serum testosterone level is the major determinant of the male-female differences in serum levels of high-density lipoprotein (HDL) cholesterol and HDL2 cholesterol

We studied prospectively the effect of exogenous testosterone (testosterone undecanoate [TU] 160 mg/d orally) on lipoprotein profiles in eight hypogonadal males and 10 females (female-to-male transsexuals). Testosterone administration to androgen-deficient men and to eugonadal women produced similar serum levels of testosterone (7.67 +/- 5.47 nmol/L v 8.45 +/- 3.81 nmol/L) and 5 alpha-dihydrotestosterone (DHT) (3.27 +/- 3.52 nmol/L v 3.97 +/- 2.35 nmol/L) in the two groups, while serum estradiol levels were three to four times higher in the females (90 +/- 24 pmol/Lv 376 +/- 315 pmol/L). After testosterone treatment serum high-density lipoprotein (HDL) cholesterol levels decreased from 1.41 +/- 0.27 mmol/L to 1.27 +/- 0.22 mmol/L after 3 months and 1.17 +/- 0.23 mmol/L after 6 months (P < .01) in female-to-male transsexuals and from 1.31 +/- 0.39 mmol/L to 1.09 +/- 0.31 mmol/L after 3 months and 1.10 +/- 0.32 mmol/L (P < .05) after 6 months in hypogonadal males. In particular, serum HDL2 cholesterol levels decreased from 0.71 +/- 0.44 mmol/L to 0.45 +/- 0.20 mmol/L after 3 months and 0.49 +/- 0.39 mmol/L after 6 months (P < .01) in female-to-male transsexuals and from 0.52 +/- 0.12 mmol/L to 0.38 +/- 0.18 mmol/L after 3 months and 0.34 +/- 0.19 mmol/L after 6 months (P < .05) in hypogonadal males. Serum apolipoprotein (apo) A1 levels decreased concomitantly. In both sexes, serum levels of HDL cholesterol and HDL2 cholesterol decreased by approximately 15% and 35%, respectively, whereas serum levels of total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol, apo A2, and apo B were not affected.(ABSTRACT TRUNCATED AT 250 WORDS)