Cytochrome c oxidase in rat adrenal and liver: effects of anti-androgen treatment and studies in testicular feminized rats

Actions of 17β-estradiol and testosterone in the mitochondria and their implications in aging

A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging.

Expression of mitochondrial biogenesis-signaling factors in brown adipocytes is influenced specifically by 17beta-estradiol, testosterone, and progesterone

Control of mitochondrial biogenesis in brown adipose tissue (BAT), as part of the thermogenesis program, is a complex process that requires the integration of multiple transcription factors to orchestrate mitochondrial and nuclear gene expression. Despite the knowledge of the role of sex hormones on BAT physiology, little is known about the effect of these hormones on the mitochondrial biogenic program. The aim of this study was to determine the effect of testosterone, 17beta-estradiol, and progesterone on the expression of nuclear factors involved in the control of mitochondrial biogenesis and thermogenic function such as ppargamma, pgc1alpha, nrf1, gabpa, and tfam, and also an inhibitor of PI3K-Akt pathway, recently found to be involved in the control of mitochondrial recruitment (pten). For this purpose, an in vitro assay using cell-cultured brown adipocytes was used to address the role of steroid hormones, progesterone, testosterone, and 17beta-estradiol on the mRNA expression of these factors by real-time PCR. Thus 17beta-estradiol seemed to exert a dual effect, activating the PI3K-Akt pathway by inhibiting pten mRNA expression and also inhibiting nrf1 and tfam mRNA expression. Progesterone seemed to positively stimulate mitochondriogenesis and BAT differentiation by increasing the mRNA expression of the gabpa-tfam axis and ppargamma, respectively, but also exerted a negative output by increasing pten mRNA levels. Finally, testosterone inhibited the transcription of pgc1alpha, the master factor involved in UCP1 expression and mitochondrial biogenesis. In conclusion, our results support the idea that sex hormones have direct effects on different mediators of the mitochondriogenesis program.

Stress from exercise in the below sea level environment causes an increase in serum testosterone levels in trained athletes

A comparative study (n = 20) of serum levels of leutinizing hormone (LH) and testosterone (T) between male trained athletes (high-school students, 16-18 years old) living in North and South Shouna in the Jordan Valley (JV), 320-360 meters below sea level, and those living in Ramtha and Irbid, 550-650 meters above sea level, was conducted in November, 1999. Serum levels of LH and T were also measured in these athletes following a 20 Km noncompetitive run. The air temperatures on the day of the experiment was comparable (25 degrees C in North and South Shouna versus 23 degrees C in Ramtha and Irbid). Before exercise, serum levels of LH and T in athletes of the below sea level environment (North and South Shouna) were similar to those levels in athletes of the above sea level environment (Ramtha and Irbid). Exercise caused a significant increase in serum levels of both LH and T only in athletes of North and South Shouna. It seems likely that the higher secretion of LH contributes, at least in part, for the higher serum levels of T following exercise. Taken together, these data suggest that exercise has an effect on LH and T secretion that is similar to that of fasting. And finally, the below sea level environmental factors, such as the high barometric pressure, as well as the genetic background of the athletes affect the pituitary and adrenal cortex as well as testicular tissue, resulting in the secretion of more LH and T.

Seasonal pattern of leutinizing, follicle-stimulating hormone, testosterone and progesterone in adult population of both sexes in the Jordan Valley

Differences were observed in hormonal levels between in both sexes of people living in Irbid City (620 meters above sea level) and in the Jordan Valley (360 meters below sea level). In addition, exercise was shown to differentially affect hormonal levels of both sexes at the above and below sea level locations. Serum levels of leutinizing hormone (LH) and testosterone (T) in adult male and serum levels of follicle-stimulating hormone (FSH) and progesterone (P) in adult female people were investigated in Irbid City and in the Jordan Valley during the years 1997 and 1998. The levels of these hormones were followed each month during this period. In males living in Irbid City, LH and T peaked from March through June, and in females at the same site, FSH and P also peaked from March through June. These data confirm the seasonal variation in sex hormones reported elsewhere in (wo)man and in other species. In males and females of the Jordan Valley, serum levels of LH, FSH, T and P were all higher than those of Irbid City throughout the year. Additionally, peaks of LH and T in male and FSH and P in female subjects in the Jordan Valley were observed from March through September. The high levels of these hormones and the extension of their peaks are suggested to be due to effects of the environmental factors of the Jordan Valley (high temperature, high barometric pressure) compared to those in Irbid City and other areas located at above sea level altitude.