Discovery of novel serum metabolic biomarkers in patients with polycystic ovarian syndrome and premature ovarian failure

Several widely recognized metabolites play a role in regulating the pathophysiological processes of various disorders. Nonetheless, the lack of effective biomarkers for the early diagnosis of polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF) has led to the discovery of serum-based metabolic biomarkers for these disorders. We aimed to identify various differentially expressed metabolites (DEMs) through serum-based metabolic profiling in patients with PCOS and POF and in healthy individuals by using liquid chromatography–mass spectrometry analysis. Furthermore, heatmap clustering, correlation, and Z-score analyses were performed to identify the top DEMs. Kyoto Encyclopedia of Genes and Genomes enriched pathways of DEMs were determined using metabolite-based databases. Moreover, the clinical significance of these DEMs was evaluated on the basis of area under the receiver operating characteristic curve. Significantly dysregulated expressions of several metabolites were observed in the intergroup comparisons of the PCOS, POF, and healthy control groups. Furthermore, 6 DEMs were most frequently observed among the three groups. The expressions of these DEMs were not only directly correlated but also exhibited potential significance in patients with PCOS and POF. Novel metabolites with up/downregulated expressions can be discovered in patients with PCOS and POF using serum-based metabolomics; these metabolites show good diagnostic performance and can act as effective biomarkers for the early detection of PCOS and POF. Furthermore, these metabolites might be involved in the pathophysiological mechanisms of PCOS and POF via interplay with corresponding genes.

Matrigel/Umbilical Cord-Derived Mesenchymal Stem Cells Promote Granulosa Cell Proliferation and Ovarian Vascularization in a Mouse Model of Premature Ovarian Failure

In women of reproductive age, severe injuries to the ovary are often accompanied by premature ovarian failure (POF), which can result in amenorrhea or infertility. Hormone replacement therapy has been used to treat POF; however, it has limited therapeutic efficiency and may cause several side effects. In this study, we aimed to fabricate a Matrigel scaffold loaded with human umbilical cord-derived mesenchymal stem cells (MSCs) and explore its potential to restore ovarian function and repair ovarian structures in vitro and in vivo. POF mouse models were established by injecting mice with cyclophosphamide for 15 consecutive days. Then, MSC/Matrigel was transplanted into the ovaries of the mice. Five weeks later, the morphology of the ovaries and follicles was observed by hematoxylin/eosin staining, and the tissue fibrosis ratio was measured using Masson's trichrome staining. The number of blood vessels was evaluated by α-smooth muscle actin and CD31 immunofluorescence, and Ki67 expression was used to determine the proliferation of granulosa cells. The expression of vascular endothelial growth factor (VEGF)-A was assessed by western blotting. The Matrigel scaffold regulated the expression of VEGF-A in vitro. Moreover, it promoted MSC survival and proliferation and prevented MSC apoptosis in vivo. After the transplantation of the MSC/Matrigel, the number of follicles was significantly increased in the mice with POF, and the tissue fibrosis ratio was reduced. Furthermore, the MSC/Matrigel significantly improved the proliferation rate of granulosa cells, increased the number of blood vessels, and upregulated the expression of VEGF-A. These findings demonstrate that MSC/Matrigel may support follicular development and help restore ovarian structures in vivo.

Thiol-disulfide homeostasis and ischemia-modified albumin as a marker of oxidative stress in patients with sarcopenia

AIM

Sarcopenia is characterized by progressive and generalized loss of skeletal muscle mass and strength. Chronic inflammatory conditions and increased oxidative stress are in the pathogenesis of sarcopenia. Our aim was to evaluate the relationship between sarcopenia and thiol-disulfide homeostasis and ischemia-modified albumin levels as an oxidative stress marker.

METHODS

Patients aged ≥65 years were recruited in this study. Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People criterion. Total thiol, native thiol, disulfide and ischemia-modified albumin levels were measures according to clinical and laboratory features. Patients were divided into two groups according to their sarcopenia presence; thiol-disulfide homeostasis and ischemia-modified albumin levels were evaluated between these groups.

RESULTS

Overall, 94 patients were analyzed. The mean age was 75.0 ± 6.71 years. A total of 39% of the patients were diagnosed as probable sarcopenia, 3.2% had sarcopenia, 6.4% had severe sarcopenia and 51.1% were diagnosed as normal. The levels of native thiol, total thiol, disulfide level and disulfide-native thiol, native thiol-total thiol and disulfide-total thiol ratios were similar in patients with sarcopenia when compared with the control group. In addition, there were no differences between albumin and ischemia-modified albumin levels. In univariate regression analysis, handgrip strength was found to be an independent predictor of native thiol and total thiol, and disulfide levels.

CONCLUSION

This is the first study in the literature that evaluates the thiol-disulfide homeostasis and ischemia-modified albumin levels in sarcopenic older patients. Long-term studies are warranted to confirm the relationship between oxidative stress markers and sarcopenia. Geriatr Gerontol Int 2021; 21: 584-589.

Thiol-disulfide homeostasis: an integrated approach with biochemical and clinical aspects

Dynamic thiol-disulfide homeostasis (TDH) is a new area has begun to attract more scrutiny. Dynamic TDH is reversal of thiol oxidation in proteins and represents the status of thiols (-SH) and disulfides (-S-S-). Organic compounds containing the sulfhydryl group is called thiol, composed of sulfur and hydrogen atoms. Disulfides are the most important class of dynamic, redox responsive covalent bonds build in between two thiol groups. For many years, thiol levels were analyzed by several methods. During last years, measurements of disulfide levels have been analyzed by a novel automated method, developed by Erel and Neselioglu. In this method, addition to thiol (termed as native thiol) levels, disulfide levels were also measured and sum of native thiol and disulfide levels were termed as total thiol. Therefore, TDH was begun to be understood in organism. In healthy humans, TDH is maintained within a certain range. Dysregulated dynamic TDH has been implicated several disorders with unknown etiology. A growing body of evidence has demonstrated that the thiol-disulfide homeostasis is involved in variety diseases, such as diabetes mellitus, hypertension, nonsmall cell lung cancer, familial Mediterranean fever (FMF), inflammatory bowel diseases, occupational diseases, gestational diabetes mellitus and preeclampsia. These results may elucidate some pathogenic mechanism or may be a predictor indicating diagnostic clue, prognostic marker or therapeutic sign. In conclusion, protection of the thiol-disulfide homeostasis is of great importance for the human being. Evidence achieved so far has proposed that thiol-disulfide homeostasis is an important issue needs to elucidate wholly.

The role of oxidative stress on subclinical atherosclerosis in premature ovarian insufficiency and relationship with carotid intima-media thickness

Objective: We aimed to investigate the relationship between oxidative stress (OS) and subclinical atherosclerosis in patients with premature ovarian insufficiency (POI), by analyzing the dynamic thiol/disulfide homeostasis (TDH) parameters as an OS marker and carotid intima-media thickness (CIMT).Materials and methods: A total of 69 women, 34 with POI and 35 healthy controls were included in this prospective cross-sectional study. TDH parameters (plasma native thiol, total thiol, disulfide, disulfide/native thiol, native thiol/total thiol, and disulfide/total thiol ratios) and CIMT were measured and compared between the two groups.Results: In primary ovarian insufficiency group, native thiol (p=.009) and total thiol (p=.010) levels were significantly decreased, and CIMT values were significantly increased (p= <.001). CIMT values were negatively correlated with native thiol (r=-0.553, p=.001) and total thiol levels (r=-0.565, p=.001); and positively correlated with age (r = 0.457, p=.007), BMI (r = 0.408, p=.017), and total cholesterol (r = 0.605, p<.001) in POI group.Conclusions: Decreased native thiol and total thiol levels demonstrate the defective anti-oxidant mechanism in POI. Negative correlation between native thiol, total thiol levels, and CIMT means the presence of abnormal anti-oxidant mechanisms may play a role in the development of subclinical atherosclerosis in patients with POI. This is a novel report on the mechanism of subclinical atherosclerosis in women with POI, which needs to be supported with further studies evaluating the pathophysiology of OS.

Does thiol/disulfide homeostasis affect the number of metaphase 2 oocyte in the treatment of in vitro fertilization?

Aim:

To investigate the effect of thiol/disulfide homeostasis on the number of oocytes retrieved and metaphase 2 (M2) oocytes in patients undergoing in vitro fertilization.

Method:

A prospective study of 94 patients who were admitted to the in vitro fertilization clinic was conducted. Serum samples were taken on the oocyte pick-up day and kept until the analysis. Thiol and disulfide were measured in order to evaluate the total thiol/disulfide.

Results:

A statistically significant correlation was observed between disulfide and M2.

Conclusion:

This study provides an inexpensive and noninvasive method to measure oxidative stress, and suggests that there is a positive correlation between the number of M2 and disulfide, resulting in low-impact oxidative stress.

In vitro fertilization success is a most important issue, and a lot of factors have been shown to affect its success. Oxidative stress is one of the most important of these factors. There are a lot of ways to measure oxidative stress, and here we wanted to show the effect of oxidation in in vitro fertilization success by using a new, cheaper method. The study provides an important contribution to the literature by showing the positive effect of a small amount of oxidative stress on oocyte maturation.

Premature ovarian failure and tissue engineering

Premature ovarian failure (POF) usually happens former to the age of 40 and affects the female physiological state premenopausal period. In this condition, ovaries stop working long before the expected menopausal time. Of diagnostic symptoms of the disease, one can mention amenorrhea and hypoestrogenism. The cause of POF in most cases is idiopathic; however, cancer therapy may also cause POF. Commonly utilized therapies such as hormone therapy, in-vitro activation, and regenerative medicine are the most well-known treatments for POF. Hence, these therapies may be associated with some complications. The aim of the present study is to discuss the beneficial effects of tissue engineering for fertility rehabilitation in patients with POF as a newly emerging therapy.

A novel biomarker explaining the role of oxidative stress in exercise and l-tyrosine supplementation: thiol/disulphide homeostasis

The present study aimed to evaluate the relationship between exercise and both l-tyrosine and oxidative stress using thiol/disulphide homeostasis via a novel biomarker in rats. Following the completion of the exercise and l-tyrosine protocol, serum total thiol, native thiol, and disulphide concentrations were determined using a novel automated measurement method. Compared with the control group, serum dynamic disulphide levels were significantly lower in the E group (116.75 ± 10.49; p < .05) and the highest in the LT group (151.0 ± 5.84). The lowest oxidised thiol (49.75 ± 6.18; p = .087) and the highest reduced thiol (75.38 ± 3.16; p = .079) rates were determined to be in the E group. The highest oxidised thiol value was observed in the LT group. Exercise positively affects thiol/disulphide homeostasis, which is a novel indicator of oxidant-antioxidant parameters. Additionally, l-tyrosine appears to be more convenient combined with exercise. The new method used in our study proposes a promising, practical, and useful method for assessing the oxidative stress parameters.

Investigation of serum thiol/disulphide homeostasis in patients with abortus imminens

AIM

The aim of our study is to compare serum thiol/disulphide homeostasis of women diagnosed with abortus imminens (AI) and healthy pregnant women, and to determine whether it has a role in the pathogenesis of the disease or not.

MATERIALS AND METHODS

A total of 100 pregnant women were included in the study. The study group consisted of 50 patients with AI whereas 50 healthy pregnant women were chosen as the control group. All of the patients in the two groups were matched for age, gestational age, and body mass index. Thiol/disulphide levels were analyzed with a newly developed automated spectrophotometric method.

RESULTS

We found significantly reduced levels of native thiol (SH) (370.2 ± 35.2 μmol/l versus 397.6 ± 29.3 μmol/l) and total thiol (406 ± 37.1 μmol/l versus 434.5 ± 29.9 μmol/l), in the sera of the study group compared to the control group (p < .001). But serum levels of disulphide (SS) were statistically insignificant between the two groups (17.9 ± 5.9 μmol/l versus 18.4 ± 4.9 μmol/l, p: .612). Similarly, no significant differences were observed between the two groups in terms of SS/SH, SS/total thiol and SH/total thiol ratios (all p > .05).

CONCLUSIONS

We found a decrease in thiol levels which have antioxidant properties in patients with AI. Decreased antioxidant level in the body is thought to play a role in the etiology of AI. In this regard, further studies are needed to elucidate the potential role of dynamic thiol/disulphide homeostasis in the pathogenesis of AI.