Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2022 Nov;39(11):2439-2473.
doi: 10.1007/s10815-022-02625-7. Epub 2022 Oct 3.

A brief insight into the etiology, genetics, and immunology of polycystic ovarian syndrome (PCOS)

Affiliations
Review

A brief insight into the etiology, genetics, and immunology of polycystic ovarian syndrome (PCOS)

Sana Siddiqui et al. J Assist Reprod Genet. 2022 Nov.

Abstract

Polycystic ovarian syndrome (PCOS) is a prevailing endocrine and metabolic disorder occurring in about 6-20% of females in reproductive age. Most symptoms of PCOS arise early during puberty. Since PCOS involves a combination of signs and symptoms, thus it is considered as a heterogeneous disorderliness. The most accepted diagnostic criteria is Rotterdam criteria which involves two of the latter three features: (a) hyperandrogenism, (b) oligo- or an-ovulation, and (c) polycystic ovaries. The persistent hormonal imbalance leads to multiple small antral follicles formation and irregular menstrual cycle, ultimately causing infertility among females. Insulin resistance, cardiovascular diseases, abdominal obesity, psychological disorders, infertility, and cancer are also related to PCOS. These pathophysiologies associated with PCOS are interrelated with each other. Hyperandrogenism causes insulin resistance and hyperglycemia, leading to ROS formation, oxidative stress, and abdominal adiposity. In consequence, inflammation, ROS production, insulin resistance, and hyperandrogenemia also increase. Elevation of AGEs in the body either produced endogenously or consumed from diet exaggerates PCOS symptoms and is also related to ovarian dysfunction. This review summarizes how AGE formation, inflammation, and oxidative stress are significantly essential in PCOS progression. Alterations during prenatal development like exposure to excess AMH, androgens, or toxins (bisphenol-A, endocrine disruptors, etc.) may also be the etiologic mechanism behind PCOS. Although the etiology of this disorder is unclear, environmental and genetic factors are primarily involved. Physical inactivity, as well as unhealthy eating habits, has a vital role in the progression of PCOS. This review outlines a collection of specific genes phenotypically linked with PCOS. Furthermore, beneficial effect of metformin in maintaining endocrine abnormalities and ovarian function is also mentioned. Kisspeptin is a protein which helps in onset of puberty and increases GnRH pulsatile release during ovulation as well as role of KNDy neurons in GnRH pulsatile signal required for reproduction are also elaborated. This review also focuses on the immunology related to PCOS involving chronic low-grade inflammation, and how the alterations within the follicular microenvironment are intricated in the development of infertility in PCOS patients. How PCOS develops following antiepileptic and psychiatric medication is also expanded in this review. Initiation of antiandrogen treatment in early age (≤ 25 years) might be helpful in spontaneous conception in PCOS women. The role of BMP (bone morphogenetic proteins) in folliculogenesis and their expression in oocytes and granulosa cells are also explained. GDF8 and SERPINE1 expression in PCOS is given in detail.

Keywords: AMH; Advanced glycation end products (AGEs); Antiandrogen treatment; BMP (bone morphogenetic proteins); Chronic low-grade inflammation; GDF8; Genetics; Hyperandrogenism; Insulin resistance; Kisspeptin; Metformin; Oxidative stress; Polycystic ovarian syndrome; SERPINE1.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Abdominal adiposity, hyperinsulinemia, hyperandrogenism, inflammation, and oxidative stress are involved in the development of PCOS. Persistent hyperinsulinemia causes insulin resistance which in turn triggers ovarian theca cells to increase androgen production leading to hyperandrogenism. Abdominal adiposity also triggers hyperandrogenism, cytokine secretion, oxidative stress, which leads to inflammation and poor oocyte quality
Fig. 2
Fig. 2
Factors involved in the etiology of PCOS
Fig. 3
Fig. 3
Pathophysiological mechanism of PCOS, depicting defects in hypothalamic-pituitary-ovarian axis, adrenal cortex, increasing oxidative stress, and pro-inflammatory cytokines
Fig. 4
Fig. 4
Inter-relationship between insulin resistance, AGEs (advanced glycation end products), inflammation, and oxidative stress
Fig. 5
Fig. 5
Different genes having a specific role in the development of PCOS
Fig. 6
Fig. 6
Immunology involved in PCOS inflammatory cytokines and LPS circulating in the bloodstream on binding with their receptors IL-R1 and TLR-4 respectively generates an inflammatory cascade within granulosa cells by inducing expression of immune response genes through phosphorylation of NF-κB, an NLRP3 inflammasome is generated by binding of NLRP3, ASC, and caspase-1 which induces inflammation, further inflammation also damages mitochondria by generating ROS within mitochondria, this whole cascade of inflammation arrests growth of granulosa cells

Similar articles

Cited by

References

    1. A. Szilagyi and I. Szabo, “Endocrine characteristics of polycystic ovary syndrome (PCOS),” IJEB Vol.41(07) [July 2003], 2003, Accessed: Jan. 18, 2022. [Online]. Available: http://nopr.niscair.res.in/handle/123456789/17119 - PubMed
    1. Balen AH, et al. The management of anovulatory infertility in women with polycystic ovary syndrome: an analysis of the evidence to support the development of global WHO guidance. Hum Reprod Update. 2016;22(6):687–708. doi: 10.1093/HUMUPD/DMW025. - DOI - PubMed
    1. Escobar-Morreale HF. Polycystic ovary syndrome: definition, aetiology, diagnosis and treatment. Nature Rev Endocrinol. 2018;14(5):270–284. doi: 10.1038/nrendo.2018.24. - DOI - PubMed
    1. R. Azziz et al., “Polycystic ovary syndrome,” Nature Reviews Disease Primers 2016 2:110.1038/nrdp.2016.57. - PubMed
    1. Witchel SF, Oberfield SE, Peña AS. Polycystic ovary syndrome: pathophysiology, presentation, and treatment with emphasis on adolescent girls. J Endocr Soc. 2019;3(8):1545–1573. doi: 10.1210/JS.2019-00078. - DOI - PMC - PubMed

Substances