Copper and Selenium stimulates CYP19A1 expression in caprine ovarian granulosa cells: possible involvement of AKT and WNT signalling pathways

Association between female circulating heavy metal concentration and abortion: a systematic review and meta-analysis

Objective

This study aimed to evaluate the association between blood heavy metal (zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd)) concentrations and spontaneous abortion (SA) and recurrent pregnancy loss (RPL) and explore the possible endocrine dysfunction associated with it.

Methods

A literature search was performed in the PubMed, Embase, Cochrane Library, and Web of Science databases up to April 2023. The overall effects were expressed as the standard mean difference (SMD). Subgroup analysis was performed according to the type of abortion (SA or RPL). Stata 16.0 was utilized for data analysis.

Results

Based on the integrated findings, abortion women showed significantly lower Zn (SMD = -1.05, 95% CI: -1.74 to -0.36, p = 0.003) and Cu concentrations (SMD = -1.42, 95% CI: -1.97 to -0.87, p <0.001) and higher Pb (SMD = 1.47, 95% CI: 0.89-2.05, p <0.001) and Cd concentrations (SMD = 1.15, 95% CI: 0.45-1.85, p = 0.001) than normal pregnant women. Subgroup analysis showed that Zn and Cu deficiency and Cd and Pb exposure were significantly (p <0.05) associated with RPL, whereas Cu deficiency and Cd and Pb exposure were significantly (p <0.05) associated with SA.

Conclusion

Zn and Cu deficiencies and Pb and Cd exposure were associated with abortion. Endocrine dysfunction, such as insulin resistance, vitamin D insufficiency, and abnormal thyroid and sex hormone concentrations, is thought to be involved in heavy metal-related abortion.

Association between Serum Copper, Selenium, Zinc, and Serum Estradiol in Women

Objectives. The objective is to examine the associations between serum copper, selenium, zinc, and serum estradiol (E2) among 2388 female participants from the National Health and Nutrition Examination Survey (NHANES). Methods. To estimate the association between serum copper, selenium, zinc, and serum E2, multivariate logistic regression analyses were conducted. Fitted smoothing curves and generalized additive models were also performed. Results. After adjusting for confounding factors, it was found that female serum copper was positively correlated with serum E2. The relationship between serum copper and E2 showed an inverted U-shaped curve (inflection point: 28.57 μmol/L). Serum selenium in women was negatively correlated with serum E2, and in the subgroup of women aged 25-55, the relationship between serum selenium and E2 showed an inverted U-shaped curve (inflection point: 1.39 μmol/L). There was no correlation between serum zinc and serum E2 in women. Conclusions. Our study revealed a correlation between serum copper and selenium and serum E2 in women and identified an inflection point for each.

Arsenic exposure diminishes ovarian follicular reserve and induces abnormal steroidogenesis by DNA methylation

Arsenic contamination is a worldwide public health problem, and the effect of arsenic on male reproduction has been extensively studied; however, data on the biotoxicity of arsenic in terms of female reproduction are more scarce. In this study, a human-cell-animal translational strategy was applied to explore the effect of arsenic exposure on ovarian steroidogenesis and its potential mechanism. We conducted a 1:1 propensity score matched case-control study involving 127 diminished ovarian reserve (DOR) cases and 127 healthy controls. The ovarian follicular fluid levels of 21 metal elements, including arsenic, were measured. The results showed that there were significant differences in follicular fluid metal profiles between DOR patients and controls and that arsenic, molybdenum, and strontium played important roles in DOR progression [OR (95 % CI): 2.203 (1.385, 3.503), 2.308 (1.490, 3.575) and 2.922 (1.864, 4.580), respectively]. In the primary ovarian granulosa cell culture model, we found that treatment with 8 μM arsenic for 24 and 48 h induced a decrease in human granulosa cell viability. The estradiol (E₂) level was significantly decreased after arsenic exposure (P < 0.05), which was dependent on significant alterations (P < 0.05) in key enzymes in steroidogenesis. In addition, a model for sodium arsenite exposure through water in rats from weaning to sexual maturity was established. We evaluated ovarian development by monitoring the estrous cycle, observing ovarian pathology, and calculating the follicular proportion. RT-qPCR, Western blotting, and bisulfite-sequencing PCR were used to investigate the effect of arsenic exposure on ovarian steroidogenesis and its possible mechanism. The results indicated that steroidogenic factor-1 (SF-1) was an important target of the steroidogenesis disorder induced by arsenic exposure. Arsenic significantly increased the DNA methylation level (P < 0.05) in the promoter region of SF-1 to reduce its expression, subsequently decreasing the levels of steroidogenic acute regulatory protein (StAR), P450 cholesterol side-chain cleavage enzyme (CYP11A1), and aromatase (CYP19A1) (P < 0.05), leading to premature depletion of ovarian follicles.