Impact of Aging on Steroid Hormone Biosynthesis and Secretion

Abstract

Steroid hormones are lipophilic, low-molecular weight organic compounds all of which are derived from cholesterol. They are primarily synthesized by steroidogenic glands such as gonads (ovary and testis), the adrenal gland and, during pregnancy, by the placental trophoblasts. Limited steroid synthesis also takes place in the brain. Steroid hormones are crucial for the proper functioning of the body. They mediate a wide variety of vital physiological functions, ranging from maintaining normal reproductive function and secondary sexual characteristics, to regulating virtually every metabolic process in the body. Like many age-related endocrine disorders, aging also progressively impacts the tissue-specific synthesis and secretion of steroid hormones. The goal of this review is to summarize the effects of aging on steroid hormone synthesis and secretion by the adrenal gland and gonads of both human and experimental animal models, to describe the potential involvement of excessive oxidative stress in mediating age-related alterations in steroidogenesis, and to discuss the possible underlying mechanisms involved.

p38 MAPK regulates steroidogenesis through transcriptional repression of STAR gene

“…Extensive experimental evidence now indicates that aging in humans and animal models is associated with a general decline in steroid hormone production (Zaidi, et al 2012). Similarly, a number of in vitro studies have clearly shown that isolated adrenocortical cells and testicular Leydig cells (Zaidi et al 2012) of older rats of several different strains synthesize and secrete less steroid hormone in response to tropic hormone or its second messenger, cAMP, than do cells from young animals.…”

“…Similarly, a number of in vitro studies have clearly shown that isolated adrenocortical cells and testicular Leydig cells (Zaidi et al 2012) of older rats of several different strains synthesize and secrete less steroid hormone in response to tropic hormone or its second messenger, cAMP, than do cells from young animals. These changes in steroid hormone production and secretion do not appear to be a function of reduced tropic hormone signaling or a defect in steroid hormone synthesizing enzymes.…”

“…Previous work from this laboratory has shown that an adequate amount of cholesterol is not available to the adrenal (adrenocortical cells) and testis (Leydig cells) in aging rats (Liao, et al 1993; Popplewell and Azhar 1987; Sun, et al 2008; Zaidi et al 2012) for the initial and rate limiting step in steroid biosynthesis, i.e., translocation of cholesterol from the outer mitochondrial membrane to the P450 side-chain cleavage enzyme (P450scc/Cyp11A1), which is localized in the matrix side of the inner mitochondrial membrane and converts cholesterol to pregnenolone, the precursor of all steroid hormones (Hu, et al 2010; Miller and Bose 2011; Stocco and Clark 1996; Stocco 2001). This aging-induced attenuation of cholesterol transport to mitochondria is not due to a loss of cellular cholesterol stores, but results from down-regulation of steroidogenic acute regulatory protein (StAR) (Leers-Sucheta, et al 1999; Luo, et al 2001; Sun et al 2008; Wang, et al 2005), and peripheral-type benzodiazepine receptor (PBR) or translocator protein (TSPO) (Culty, et al 2002; Sun et al 2008).…”

Experimental Study for the Effect of Methyl Rednisolone on the Sexual Hormones Levels

“…Steroid hormones contain steroid nucleus and synthesized in the body from cholesterol , steroid hormones are a steroid that acts as hormones , it's endogenously derived from Cholesterol , the main classification of steroid hormones are corticosteroids ( typically made in the adrenal cortex , hence corticoids ) and sex steroids hormones which include androgens (male sex hormones) , oestrogens (female or follicular hormones) and gestogens (corpus luteum hormone ) [5]. Sex hormones belong to steroid hormones that are secreted by genital glands ( testes and ovaries ) and adrenal cortex and the placenta during pregnancy .…”

Experimental study of the influence of recombinant human lactoferrin on the levels of androgens and basic parameters of lipid and protein metabolism

“…Помимо общеизвестной роли в регуляции половой функции, тестостерон обладает разносторонним стимулирующим действием на организм: активирует анаболические реакции, выражающиеся, в частности, в наращивании мышечной массы и уменьшении висцерального жира; поддерживает нормальное функционирование центральных нейронов; увеличивает экспрессию ряда регуляторных белков [6,7]. Показано его влияние на клеточный и гуморальный ответ иммунной системы [8].…”