Discovery of distinct protein profiles for polycystic ovary syndrome with and without insulin resistance by surface-enhanced laser adsorption/ionization time of flight mass spectrometry

Multi-omics insights and therapeutic implications in polycystic ovary syndrome: a review

Polycystic ovary syndrome (PCOS) is a common gynecological disease that causes adverse effects in women in their reproductive phase. Nonetheless, the molecular mechanisms remain unclear. Over the last decade, sequencing and omics approaches have advanced at an increased pace. Omics initiatives have come to the forefront of biomedical research by presenting the significance of biological functions and processes. Thus, multi-omics profiling has yielded important insights into understanding the biology of PCOS by identifying potential biomarkers and therapeutic targets. Multi-omics platforms provide high-throughput data to leverage the molecular mechanisms and pathways involving genetic alteration, epigenetic regulation, transcriptional regulation, protein interaction, and metabolic alterations in PCOS. The purpose of this review is to outline the prospects of multi-omics technologies in PCOS research by revealing novel biomarkers and therapeutic targets. Finally, we address the knowledge gaps and emerging treatment strategies for the management of PCOS. Future PCOS research in multi-omics at the single-cell level may enhance diagnostic and treatment options.

Association of Serum Heavy Metals and Trace Element Concentrations with Reproductive Hormone Levels and Polycystic Ovary Syndrome in a Chinese Population

To investigate the serum concentrations of 11 heavy metals and trace elements in patients with polycystic ovary syndrome (PCOS). A total of 369 women (including 96 patients with PCOS) were studied. No differences with statistical significance in the median barium, cadmium, lead, arsenic, chromium, gallium, strontium, and vanadium concentrations were observed between the patients with PCOS and the control group. Serum nickel (Ni) (P = 0.000) and copper (Cu) (P = 0.000) levels were significantly higher, but zinc (Zn) levels (P = 0.009) were significantly lower in patients with PCOS compared with the control group. The results of the association between metal levels and hormone levels indicated that Ni, Cu, and Zn may play a role in the pathogenesis of PCOS related with reproductive hormone levels. The findings in the present study should be investigated with further trials in order to obtain new insights into PCOS.

Validation of proteomic biomarkers previously found to be differentially expressed in women with polycystic ovary syndrome: a cross-sectional study

OBJECTIVES

The aim of this study was to independently validate proteomic biomarkers previously reported to be differentially expressed in women with Polycystic Ovary Syndrome (PCOS) compared with controls. This study focused on plasma proteomic biomarkers.

METHODS

This was a cross-sectional study at the University of Nottingham, in which samples from 30 PCOS and 30 control women were analysed by Western blotting.

RESULTS

Mean abundance ratios from Western blots of plasma total haptoglobin and haptoglobin beta proteins were 1.25 (CI 1.11-1.4) and 1.24 (CI 1.04-1.44). The mean abundance ratio from the blots of alpha-2 macroglobulin was however 1.05 (CI, 1-1.1). The mean PCOS/control BMI ratio was 1.18 (CI 1.17-1.20). There was no correlation between PCOS/control BMI ratio and alpha-2 macroglobulin, total haptoglobin and haptoglobin beta abundance ratios. There was also no correlation between PCOS/control insulin ratio and alpha-2 macroglobulin, total haptoglobin and haptoglobin beta abundance ratios.

CONCLUSIONS

Total haptoglobin and haptoglobin beta chain protein abundance was found to be elevated in women with PCOS compared with controls. We were unable to confirm decreased alpha-2 macroglobulin levels as reported in a previous study. Independent validation studies are required to validate early promising proteomic biomarkers in PCOS.

Proteomic and metabolomic approaches to the study of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is considered a complex multifactorial disorder resulting from the interaction of genetic, environmental, and lifestyle influences. Nontargeted proteomics and metabolomics have been used in the past years with the aim of identifying molecules potentially involved in the pathophysiology of this frequent disorder. The biomolecules identified so far participate in many metabolic pathways, including energy metabolism (glucose and lipid metabolism), protein metabolic processes and protein folding, cytoskeleton structure, immune response, inflammation and iron metabolism, fibrinolysis and thrombosis, oxidative stress and intracellular calcium metabolism. These molecules provide key information about molecular functions altered in PCOS and raise questions concerning their precise role in the pathogenesis of this syndrome. The biomolecules identified by nontargeted proteomic and metabolomic approaches should be considered as candidates in future studies aiming to define specific molecular phenotypes of PCOS.

Different protein expression patterns associated with polycystic ovary syndrome in human follicular fluid during controlled ovarian hyperstimulation

Polycystic ovary syndrome (PCOS) is one of the most common causes of anovulatory infertility, affecting 5-10% of females during their reproductive life. Currently the pathology of PCOS is largely unknown. To identify the differential protein expression in follicular fluids from PCOS and normal subjects during controlled ovarian hyperstimulation, we performed an initial proteomic study including two-dimensional gel electrophoresis (2DE) analysis and mass spectroscopy, and confirmed results by western blot. Thirty-two protein spots were shown to be significantly differentially expressed between PCOS and normal follicular fluids, of which 20 unique proteins were identified to be associated with cellular metabolism and physiological processes; 13 of these proteins were upregulated while seven were downregulated in PCOS follicular fluids. Western blotting analyses confirmed the differential expressions for three randomly selected proteins, i.e. upregulated α1-antitrypsin, apolipoprotein A-I and transferrin in follicular fluid from PCOS patients than normal controls. Furthermore, semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that mRNA levels of serine palmitoyltransferase 2, serine/threonine-protein kinase male germ cell-associated kinase (MAK) and DNA damage-regulated autophagy modulator protein 2 decreased significantly in granulosa cells of PCOS patients compared with normal samples. These results increase our understanding of PCOS and the identified genes may serve as candidate biomarkers to develop diagnostic and therapeutic tools.

Nature of light: spectroscopic techniques in obstetrics and gynecology applications

In recent years, advances in spectroscopic techniques led to an increase in their medical applications. In medical sciences, emphasis is increasingly placed on instrumental techniques and accurate, quantitative measurements. It is especially apparent in diagnosis, where imaging techniques and laboratory results have became invaluable and compulsory. Breakthroughs in biochemistry made it possible to characterize physiological processes and living organisms at the molecular level. This led to a proliferation of new methods such as DNA tests and the use of biomarkers in daily clinical practice. Characterization of molecular structure and determination of the composition of a mixture are the fields of analytical chemistry and analytical biochemistry.

Application of proteomics to the study of polycystic ovary syndrome

BACKGROUND

Clinical proteomics consists of qualitative and quantitative profiling of proteins present in clinical specimens such as body fluids or tissues, with the aim of discovering novel proteins and cellular pathways associated with the disease of interest.

AIM

To review the proteomic studies conducted to date that addressed different aspects of the pathogenesis of polycystic ovary syndrome (PCOS).

METHODS

Descriptive review of studies that applied proteomic techniques to the study of PCOS. Published articles were identified using the Entrez-PubMed online search facilities.

RESULTS

Most studies conducted to date focused on protein variations in plasma and different target tissues. Plasma proteomics analysis revealed that PCOS associates changes in protein expression in several acute-phase response proteins. Moreover, some of these molecules play major roles in iron metabolism and low-grade chronic inflammation. Studies using omental adipose tissue from morbidly obese women with or without PCOS revealed differences in abundance of proteins that may be involved in lipid and glucose metabolism, oxidative stress processes, and adipocyte differentiation. Moreover, identification of differentially expressed proteins in ovarian tissue, granulosa cells or T lymphocites may help to characterize more clearly some aspects of this disorder.

CONCLUSIONS

Although the application of proteomic techniques to the study of PCOS is in its early infancy, studies conducted to date highlight its heterogeneous nature. Aside from androgen excess, several pathways related to intermediate metabolism, oxidative stress processes, inflammation and iron metabolism appear to be involved in the pathophysiology of PCOS.

Association of TRB3 Q84R polymorphism with polycystic ovary syndrome in Chinese women

BACKGROUND

Tribbles 3 (TRB3) affects insulin signalling by inhibiting insulin-stimulated Akt phosphorylation and subsequent activation. A single nucleotide polymorphism located in the second extron of the human TRB3 gene is thought to be associated with insulin resistance. The latter is a core abnormality in PCOS independent of obesity. The present study was designed to clarify the relationships of TRB3 Q84R polymorphism with PCOS in a Chinese women group.

METHODS

A case-control study with two groups: PCOS group (n = 336) and control group of infertility women for tubal and/or male factor (n = 116) was performed. Genotyping of the TRB3 R84 variant was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

The frequency of genotype QQ in PCOS women was significantly lower, while genotype QR and RR were significantly higher than that in control group (p < 0.05). However, the difference disappeared after adjustment for BMI. At glucose1h, glucose2h and insulin2h point, the difference between QQ individuals and R84 allele carriers in PCOS women reached statistical significance during OGTT (p < 0.05).

CONCLUSIONS

TRB3 Q84R polymorphism is associated with obesity and especially glucose metabolism and not associated with polycystic ovary syndrome because of compositional characteristics of phenotype in Chinese PCOS women.

Framework for a systems approach to proteomic biomarker profiling in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in females of reproductive age, and its prevalence ranges between 6 and 8%. Associated problems include infertility, menstrual disorders, hirsutism and obesity. In addition, individuals with PCOS may be at increased risk of diabetes, endometrial cancer and, possibly, cardiovascular disease and breast cancer in later life. Biomarkers identified from proteomic analyses may help to improve the clinical management of PCOS, provided that new proteomic data can be integrated with existing knowledge and/or pathways implicated in disease etiology. In this study, a database of identity, descriptions and functions/pathways has been developed from 148 published proteomic biomarkers in PCOS. From analysis of the database, a variety of pathways possibly implicated in PCOS were determined, including those related to fibrinolysis, thrombosis, the antioxidant pathway and the immune system. This database, if developed further, will provide a framework for a systems approach to profiling biomarkers in the future.

Can serum apolipoprotein C-I demonstrate metabolic abnormality early in women with polycystic ovary syndrome?

OBJECTIVE

To evaluate the role of apolipoprotein C-I (apoC-I) levels and assess relationships between apoC-I and clinical features in women with polycystic ovary syndrome (PCOS).

DESIGN

Prospective study.

SETTING

Reproductive Center of Peking University Third Hospital.

PATIENT(S)

Thirty patients with PCOS with insulin resistance, 30 patients with PCOS without insulin resistance, and 30 control individuals.

INTERVENTION(S)

Fasting serum samples.

MAIN OUTCOME MEASURE(S)

Measures of serum apoC-I, androgens, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, apoA1, apoB, heat-shock C-reactive protein, glucose, and homeostasis model assessment of insulin resistance (HOMA-IR).

RESULT(S)

We found differentially expressed proteins by use of the surface-enhanced laser adsorption/ionization (SELDI) protein chip in the serum of women with PCOS and controls. Of these, apoC-I, was highly up-regulated. ApoC-I is associated with glycometabolism and lipid metabolism, but its role in PCOS has been unknown. The serum levels of apoC-I in the patients with PCOS were statistically significantly elevated compared with those of controls, especially in women with insulin resistance. The lean PCOS women had higher apoC-I levels than controls. In patients with PCOS and without any abnormal serum lipid index, apoC-I levels were still higher than in controls. Analysis showed that apoC-I correlated with body mass index, triglycerides, high-density lipoprotein cholesterol, apoA1, and HOMA-IR.

CONCLUSION(S)

ApoC-I may have an important role in glucose and lipid metabolism, and may be useful for early demonstration of metabolic abnormality in women with PCOS.