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Female adipocyte androgen synthesis and the effects of insulin

View Article: PubMed Central - PubMed

ABSTRACT

The metabolic syndrome is a cluster of metabolic disorders characterized by insulin resistance and hyperinsulinaemia, and its presence can increase the risk of cardiovascular disease significantly. The metabolic syndrome is associated with increased circulating androgen levels in women, which may originate from the ovaries and adrenal glands. Adipocytes are also able to synthesise steroid hormones, and this output has been hypothesised to increase with elevated insulin plasma concentrations. However, the contribution of the adipocytes to the circulating androgen levels in women with metabolic syndrome is limited and the effects of insulin are not fully understood. The aim of this study was to investigate the presence of steroid precursors and synthetic enzymes in human adipocyte biopsies as markers of possible adipocyte androgen synthesis. We examined pre and mature adipocytes taken from tissue biopsies of abdominal subcutaneous adipose tissue of participating women from the Department of Obstetrics and Gynaecology, of the Royal Derby Hospital. The results showed the potential for localised adipocyte androgen synthesis through the presence of the androgen precursor progesterone, as well as the steroid-converting enzyme 17α-hydroxylase. Furthermore, we found the controlled secretion of androstenedione in vitro and that insulin treatment caused levels to increase. Continued examination of a localised source of androgen production is therefore of clinical relevance due to its influence on adipocyte metabolism, its negative impact on female steroidogenic homeostasis, and the possible aggravation this may have when associated to obesity and obesity related metabolic abnormalities such as hyperinsulinaemia.

No MeSH data available.


Comparison of mature adipocyte androstenedione secretion with and without inhibition of the insulin-signalling pathway. Mature adipocytes (n = 12) were treated with insulin with and without the PI3-K inhibitor LY292004 and androstenedione secretion measured. No significant variation was found between treated and untreated cultures.
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f0020: Comparison of mature adipocyte androstenedione secretion with and without inhibition of the insulin-signalling pathway. Mature adipocytes (n = 12) were treated with insulin with and without the PI3-K inhibitor LY292004 and androstenedione secretion measured. No significant variation was found between treated and untreated cultures.

Mentions: With the possible influence insulin may therefore play in androgen synthesis we examined a possible signalling pathway through inhibition of PI3-K, shown to be involved in ovarian steroidogenesis [31]. Fig. 4. shows that no variation in mature adipocyte androgen secretion was seen when comparing insulin stimulation of androgen secretion and inhibition of PI3-K pathway.


Female adipocyte androgen synthesis and the effects of insulin
Comparison of mature adipocyte androstenedione secretion with and without inhibition of the insulin-signalling pathway. Mature adipocytes (n = 12) were treated with insulin with and without the PI3-K inhibitor LY292004 and androstenedione secretion measured. No significant variation was found between treated and untreated cultures.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5121335&req=5

f0020: Comparison of mature adipocyte androstenedione secretion with and without inhibition of the insulin-signalling pathway. Mature adipocytes (n = 12) were treated with insulin with and without the PI3-K inhibitor LY292004 and androstenedione secretion measured. No significant variation was found between treated and untreated cultures.
Mentions: With the possible influence insulin may therefore play in androgen synthesis we examined a possible signalling pathway through inhibition of PI3-K, shown to be involved in ovarian steroidogenesis [31]. Fig. 4. shows that no variation in mature adipocyte androgen secretion was seen when comparing insulin stimulation of androgen secretion and inhibition of PI3-K pathway.

View Article: PubMed Central - PubMed

ABSTRACT

The metabolic syndrome is a cluster of metabolic disorders characterized by insulin resistance and hyperinsulinaemia, and its presence can increase the risk of cardiovascular disease significantly. The metabolic syndrome is associated with increased circulating androgen levels in women, which may originate from the ovaries and adrenal glands. Adipocytes are also able to synthesise steroid hormones, and this output has been hypothesised to increase with elevated insulin plasma concentrations. However, the contribution of the adipocytes to the circulating androgen levels in women with metabolic syndrome is limited and the effects of insulin are not fully understood. The aim of this study was to investigate the presence of steroid precursors and synthetic enzymes in human adipocyte biopsies as markers of possible adipocyte androgen synthesis. We examined pre and mature adipocytes taken from tissue biopsies of abdominal subcutaneous adipose tissue of participating women from the Department of Obstetrics and Gynaecology, of the Royal Derby Hospital. The results showed the potential for localised adipocyte androgen synthesis through the presence of the androgen precursor progesterone, as well as the steroid-converting enzyme 17α-hydroxylase. Furthermore, we found the controlled secretion of androstenedione in vitro and that insulin treatment caused levels to increase. Continued examination of a localised source of androgen production is therefore of clinical relevance due to its influence on adipocyte metabolism, its negative impact on female steroidogenic homeostasis, and the possible aggravation this may have when associated to obesity and obesity related metabolic abnormalities such as hyperinsulinaemia.

No MeSH data available.