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

Towards prolonging ovarian reproductive life: Insights into trace elements homeostasis

Ovarian aging is marked by a reduction in the quantity and quality of ovarian follicles, leading to a decline in female fertility and ovarian endocrine function. While the biological characteristics of ovarian aging are well-established, the exact mechanisms underlying this process remain elusive. Recent studies underscore the vital role of trace elements (TEs) in maintaining ovarian function. Imbalances in TEs can lead to ovarian aging, characterized by reduced enzyme activity, hormonal imbalances, ovulatory disorders, and decreased fertility. A comprehensive understanding of the relationship between systemic and cellular TEs balance and ovarian aging is critical for developing treatments to delay aging and manage age-related conditions. This review consolidates current insights into TEs homeostasis and its impact on ovarian aging, assesses how altered TEs metabolism affects ovarian aging, and suggests future research directions to prolong ovarian reproductive life. These studies are expected to offer novel approaches for mitigating ovarian aging.

Zinc deficiency deteriorates ovarian follicle development and function by inhibiting mitochondrial function

Zinc (Zn) is a crucial trace element essential for human growth and development, particularly for reproductive health. Previous research has shown a decrease in serum zinc concentration with age and individuals with conditions such as polycystic ovary syndrome (PCOS) and diabetes mellitus. However, the specific effects of zinc deficiency on the female reproductive system, especially ovarian function, are not fully understood. In our study, we observed a significant reduction in the total number of follicles and mature follicles in the zinc deficiency group. This reduction correlated with decreased level of anti-Mullerian hormone (AMH) and abnormal gene expression affecting hormone secretion regulation. Furthermore, we found that zinc deficiency disrupted mitochondrial dynamics, leading to oxidative stress in the ovaries, which further inhibited autophagy and increased ovarian apoptosis. These changes ultimately resulted in the failure of germinal vesicle breakdown (GVBD) and reduced oocyte quality. Meanwhile, administration of zinc glycine effectively alleviated the oocyte meiotic arrest caused by dietary zinc deficiency. In conclusion, our findings demonstrated that dietary zinc deficiency can affect hormone secretion and follicle maturation by impairing mitochondrial function and autophagy.

Exploring Serum Zinc and Copper Levels as Potential Biomarkers in Polycystic Ovary Syndrome: A Cross-Sectional Study From Northeast India

Introduction Polycystic ovary syndrome (PCOS) is a prevalent hormonal disorder characterized by irregular menstrual cycles, ovarian cysts, and elevated androgen levels. The potential association between trace elements, specifically copper (Cu) and zinc (Zn), and PCOS has been explored, but a definitive relationship remains unclear. This study aims to investigate the levels of these trace elements in women with PCOS and their potential implications. Methods The study, conducted at Gauhati Medical College & Hospital, involved 60 individuals with PCOS and a matched control group. Ethical approval was obtained, and participants provided written informed consent. The study spanned from July 2021 to June 2022, utilizing a hospital-based case-control study design. Diagnostic criteria adhered to the Rotterdam criteria, and serum copper and zinc levels were quantified using a double-beam UV spectrophotometer. Results In the PCOS group, the mean age was 23.01 ± 3.60 years, while the control group had a mean age of 23.34 ± 3.59 years, with no significant age difference. Mean copper levels were 147.32 ± 16.53 μg/dl in PCOS and 106.88 ± 15.60 μg/dl in controls, indicating a significant increase in PCOS (p < 0.0001). Mean zinc levels were 93.99 ± 6.76 μg/dl in PCOS and 85.42 ± 12.69 μg/dl in controls, also significantly higher in PCOS (p < 0.0001). Conclusion The study highlights significant differences in serum copper and zinc levels between women with PCOS and healthy controls, suggesting potential implications for the syndrome's pathophysiology. Further research is warranted to elucidate the precise roles of these trace elements in PCOS and explore therapeutic interventions.

Exploring the Impact of Nickel Exposure on Female Fertility

Introduction Infertility affects an estimated 186 million individuals globally and is associated with numerous mental health issues. Trace elements are essential for reproductive health, yet the role of nickel in female fertility is not well understood. Previous research has shown conflicting evidence regarding nickel's impact on ovarian function and its potential to disrupt reproductive processes. Methods We utilized data from the National Health and Nutrition Examination Survey (NHANES) focusing on a cohort of 7,839 women, with an emphasis on 1,404 women aged 18 to 35. Logistic regression was employed to investigate the relationship between urinary nickel levels and fertility status, controlling for age, BMI, and race/ethnicity. Results The fertility analysis included 880 fertile and 106 infertile women, identifying age as a significant predictor of fertility status. Nickel exposure did not demonstrate a statistically significant association with fertility. The racial distribution within the groups showed a higher proportion of non-Hispanic White women in the fertile category and Mexican American women in the infertile group, although race was not a significant predictor in the regression model. Conclusions We found no significant relationship between nickel exposure and fertility status when adjusted for race, BMI, and age. Age was the only significant factor associated with fertility. These results highlight the complexity of the interplay between environmental exposures and reproductive health, suggesting that further research is necessary to elucidate the role of nickel and other trace elements in fertility.

Minerals and the Menstrual Cycle: Impacts on Ovulation and Endometrial Health

The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between nutrition and reproductive health. This narrative review aims to elucidate the impacts of minerals on key aspects of the reproductive system: hormonal regulation, ovarian function and ovulation, endometrial health, and oxidative stress. Despite the attention given to specific micronutrients in relation to reproductive disorders, there is a noticeable absence of a comprehensive review focusing on the impact of minerals throughout the menstrual cycle on female fertility. This narrative review aims to address this gap by examining the influence of minerals on reproductive health. Each mineral's contribution is explored in detail to provide a clearer picture of its importance in supporting female fertility. This comprehensive analysis not only enhances our knowledge of reproductive health but also offers clinicians valuable insights into potential therapeutic strategies and the recommended intake of minerals to promote female reproductive well-being, considering the menstrual cycle. This review stands as the first to offer such a detailed examination of minerals in the context of the menstrual cycle, aiming to elevate the understanding of their critical role in female fertility and reproductive health.

Serum Zinc Levels in Women with Polycystic Ovarian Syndrome are Lower as Compared to Those without Polycystic Ovarian Syndrome: A Cohort Study

Background

Zinc is an essential micronutrient, a vital stabiliser and a cofactor in many enzymes such as superoxide dismutase and phospholipase C and also acts as an antioxidant by protecting the sulfhydryl groups of different proteins and enzymes against free radicals. It is unclear if serum zinc levels are correlated with polycystic ovary syndrome (PCOS) and its pathophysiology, although relation between diabetes and insulin resistance has been established.

Aims

This study aimed to investigate circulating serum zinc levels in PCOS subjects compared with non-PCOS subjects.

Settings and Design

In this cohort study, PCOS subjects were compared with normal subjects aged between 18 and 35.

Materials and Methods

All the included subjects underwent measurement of anthropometric parameters, fasting insulin, luteinising hormone, follicle-stimulating hormone, thyroid-stimulating hormone, prolactin, progesterone, oestrogen and serum zinc levels. These values were taken on days 2-5 of the menstrual cycle.

Statistical Analysis Used

Univariate analysis and linear regression were performed for serum zinc levels and fasting insulin levels in PCOS subjects and non-PCOS subjects using SPSS (version 21) and Microsoft Excel (2019).

Results

Serum zinc levels in the PCOS group were lower than in the control group (P = 0.012). Fasting insulin levels in the PCOS group were higher than in non-PCOS subjects (P = 0.001). We found a negative correlation between zinc and fasting insulin (r = -0.580, P < 0.0001) in the normal group and (r = -0.332, P = 0.019) in the PCOS group. A positive correlation was found between body mass index (BMI) and fasting insulin levels in both the PCOS group (r = 0.227, P = 0.112) and normals (r = 0.612, P < 0.0001). A negative statistically significant correlation between BMI and zinc in both the PCOS group (r = -0.378, P = 0.007) and the non-PCOS group (r = -0.7452, P < 0.0001) was seen.

Conclusion

The data suggest that serum zinc levels were found to be lower in PCOS subjects as compared to normal controls and evaluation of these levels may indicate that zinc has a vital role in PCOS pathophysiology.

Investigation of the Association of Serum Trace Elements Concentrations and Serum Biochemical Parameters with the Risk of Polycystic Ovary Syndrome: a Case-Control Study

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrinological syndrome characterized by hyperandrogenism of ovarian origin and is often considered a predisposing factor for metabolic disorders. The objective of the study was to investigate serum levels of (a) trace elements (copper (Cu), zinc (Zn), magnesium (Mg), selenium (Se), iron (Fe), chromium (Cr), and manganese (Mn)); and (b) biochemical parameters (glucose, cholesterol, triglycerides, high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), albumin, total protein, creatinine, and C-reactive protein (CRP) with risk of PCOS. Another objective was to explore the relationship between serum trace elements and biochemical variables. Serum trace elements were estimated by inductively coupled plasma mass spectrometry (ICP-MS) and biochemical parameters were estimated by colorimetric methods in 99 PCOS cases and 82 controls. Linear and non-linear associations of serum variables with PCOS risk were studied under logistic, probit, GAM, and BKMR model. Statistical analyses were performed using IBM SPSS 22.0 and R package version 4.2.1. All studied serum trace elements (except Zn) are significantly associated with PCOS. Combined effect analysis revealed Mg-Se and Fe-Cu association with PCOS risk. A significant association of cholesterol, HDL-C, LDL-C, CRP, and albumin was observed. Furthermore, linear regression analysis suggests an association between Mg-Cu and Mg-Fe-Mn with HDL-C; Fe and Cr-Cu with albumin; and Cu-Se with cholesterol and LDL-C both.

Copper in Gynecological Diseases

Copper (Cu) is an essential micronutrient for the correct development of eukaryotic organisms. This metal plays a key role in many cellular and physiological activities, including enzymatic activity, oxygen transport, and cell signaling. Although the redox activity of Cu is crucial for enzymatic reactions, this property also makes it potentially toxic when found at high levels. Due to this dual action of Cu, highly regulated mechanisms are necessary to prevent both the deficiency and the accumulation of this metal since its dyshomeostasis may favor the development of multiple diseases, such as Menkes' and Wilson's diseases, neurodegenerative diseases, diabetes mellitus, and cancer. As the relationship between Cu and cancer has been the most studied, we analyze how this metal can affect three fundamental processes for tumor progression: cell proliferation, angiogenesis, and metastasis. Gynecological diseases are characterized by high prevalence, morbidity, and mortality, depending on the case, and mainly include benign and malignant tumors. The cellular processes that promote their progression are affected by Cu, and the mechanisms that occur may be similar. We analyze the crosstalk between Cu deregulation and gynecological diseases, focusing on therapeutic strategies derived from this metal.

Heavy Metals and Essential Elements in Association with Oxidative Stress in Women with Polycystic Ovary Syndrome-A Systematic Review

Altered levels of heavy metals and essential elements have been associated with oxidative stress (OS) and metabolic and hormonal changes in women with polycystic ovary syndrome (PCOS). We aimed to summarize the knowledge on the association of heavy metals and essential elements with OS in PCOS. An electronic literature search using PubMed for studies published between January 2008 and April 2023 was conducted. We evaluated heavy metals and essential elements in relation to OS in PCOS in 15 articles. PCOS women had increased antimonium (Sb), cadmium (Cd), lead (Pb), mercury (Hg), arsenic (As), tellurium (Te), thallium (Tl) and osmium (Os) blood levels and decreased zinc (Zn) blood levels; the results of copper (Cu) blood levels were conflicting. Some studies showed a significant correlation between heavy metals (Sb, Cd, Pb, Hg, As, Te and Tl) and essential elements (Se, Zn, Cr, Ca, Mg and Cu) and markers of OS and chronic inflammation. Heavy metals (Sb, Cd, Pb and Hg) and essential elements (Zn, Cr, Se, Ca, Mg and Cu) were associated with metabolic and hormonal characteristics in PCOS. There might be a possible benefit from supplementation therapy in reducing OS and endocrinological problems related to PCOS. Our review confirmed an association between heavy metals and essential elements with OS in PCOS women. This systematic review is registered in PROSPERO under number CRD42023418453.

The association between polycystic ovary syndrome and environmental pollutants based on animal and human study; a systematic review

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders. This abnormality is identified with hyperandrogenism, polycystic ovary and ovulation disorder. Environmental factors are one of the etiologies of this disease. In this systematic review, a search was performed with the keywords of polycystic ovary syndrome, PCOS, pesticides, organochlorine, heavy metals, PCBs, PAHs, bisphenol A, BPA, phthalates, mycotoxin, Tributyltin, TBT, environmental contaminants, regardless of publication time. 567 studies were obtained and after assessing 26 articles were finally selected. 61 % of the studies were attributed to bisphenol A. The positive correlation was seen between bisphenol A, tributyltin, air pollutants and organic contaminates with this disease. The association between this syndrome and bisphenol A in adolescents was also confirmed. Zinc has led to a reduction in the incidence of disease in almost all research literature. This issue can be considered in the prevention of the disease.

Female infertility in the era of obesity: The clash of two pandemics or inevitable consequence?

Obesity is an epidemic that has led to a rise in the incidence of many comorbidities: among others, reduced fertility is often under-evaluated in clinical practice. The mechanisms underlying the link between reduced fertility and obesity are numerous, with insulin resistance, hyperglycaemia and the frequent coexistence of polycystic ovary syndrome being the most acknowledged. However, several other factors concur, such as gut microbiome alterations, low-grade chronic inflammation and oxidative stress. Not only do women with obesity take longer to conceive, but in vitro fertilization (IVF) is also less likely to succeed. We herein provide an updated state-of-the-art regarding the molecular bases of what we could define as dysmetabolic infertility, focusing on the clinical aspects, as well as possible treatment.

Exposure to heavy metals and hormone levels in midlife women: The Study of Women's Health Across the Nation (SWAN)

Exposure to heavy metals may alter the circulating levels of sex hormones. However, epidemiologic studies on heavy metals and sex hormones have been limited, and results have been inconsistent. We assessed the associations of heavy metals assayed in urine, including arsenic, cadmium, lead, and mercury, with repeated measures of serum estradiol (E2), follicle-stimulating hormone (FSH), testosterone, and sex hormone-binding globulin (SHBG) levels in the Study of Women's Health Across the Nation Multi-Pollutant Study. The sample included 1355 White, Black, Chinese, and Japanese women, aged 45-56 years at baseline (1999-2000), whose serum hormone levels were repeatedly measured through 2017. Urinary metal concentrations were measured at baseline. Linear mixed effect models were used to calculate percent changes in serum hormone levels per doubling of urinary metal concentrations, adjusting for demographics, socioeconomic status, lifestyle, health-related factors, and urinary creatinine. After multivariable adjustment, a doubling of urinary metal concentration was associated with lower E2 levels by 2.2% (95% CI: 4.0%, -0.3%) for mercury and 3.6% (95% CI: 5.7%, -1.6%) for lead; higher FSH levels by 3.4% (95% CI: 0.9%, 5.9%) for lead; and higher SHBG levels by 3.6% (95% CI: 1.3%, 5.9%) for cadmium. The overall joint effect using the Bayesian kernel machine regression showed that metal mixtures were inversely associated with E2 and positively associated with FSH levels. No association was found between metals and testosterone levels. Results from this prospective cohort study demonstrate that environmental heavy metal exposures, including cadmium, mercury, and lead, may disturb circulating levels of E2, FSH, and SHBG in midlife women.

Oxidative stress in the ovaries of mice chronically exposed to a low lead concentration: A generational approach

Lead (Pb) is a heavy metal that alters the oxidation-reduction balance, affecting reproductive health and transfer during pregnancy and lactation. However, the multigenerational impact of exposure to low concentrations of Pb on mammalian ovaries has not been assessed. This study evaluated general parameters, histology, redox state (RS), protein carbonylation (PC), lipid peroxidation (LP), and hormone concentrations in the ovaries of mice (CD1® ICR) of three successive generations with both unigenerational (E1) and multigenerational (E2) exposure to 0.2 ppm lead acetate through the drinking water and a control group. Body weight, food consumption, the number of born pups, and their weight after weaning were not significantly affected by Pb exposure in E1 and E2. However, the ovaries of three successive generations of the E1 group, in which only the F0 was exposed, showed alterations in the ovarian histoarchitecture, increase in follicular atresia, decrease in the number of available follicles, and a significant RS and PC elevation that were surprisingly similar to those observed in the E2 group. LP increased in the second generation of E1 and E2, while hormone concentration was not altered. This is the first demonstration that exposure to low concentration of Pb induces multigenerational histological alterations and oxidative stress in mouse ovaries, that the termination of this exposure does not ensure the safety of later generations and that the lack of modifications in general parameters may facilitate the silent development of pathologies that affect ovarian health.

Exposure to multiple toxic metals and polycystic ovary syndrome risk: Endocrine disrupting effect from As, Pb and Ba

BACKGROUND

Polycystic ovarian syndrome (PCOS) affects 5 % ~ 20 % of women of reproductive age and is a serious health problem. Whether exposure to lead (Pb), mercury (Hg), arsenic (As), barium (Ba) or (cadmium) Cd is associated with an increased risk of PCOS, particularly their joint effect as well as their association with the clinical phenotype of PCOS is limited and unclear.

OBJECTIVES

We aimed to explore the associations of the blood Pb, Hg, As, Ba and Cd levels and risk of PCOS in Chinese women of reproductive age.

METHODS

A case-control study was used and included 369 women with PCOS and 441 controls. The levels of Pb, Hg, As, Ba and Cd were measured in fasting blood samples collected on the 2nd or 3rd day of menstruation or vaginal bleeding after drug withdrawal; basal sex hormone levels, fasting glucose and fasting insulin were measured simultaneously. Unconditional logistic regression models were used to assess the relationship of the blood Pb, Hg, As, Ba or Cd levels with PCOS risk. Bayesian kernel machine regression (BKMR) was used to assess the joint effect of Pb, Hg, As, Ba and Cd on PCOS risk and estimate which metal or metals contributed most to the association. Multiple linear regression models were used to investigate the relationships between the levels of selected metals and parameters of the clinical PCOS phenotype.

RESULTS

The mean ± SD ages of women in the case and control groups were 28.80 ± 3.39 and 28.97 ± 2.39 years, respectively; their mean ± SD BMIs were 23.86 ± 3.51 kg/m² and 22.08 ± 3.14 kg/m², respectively. The blood levels of three metals (Pb, As and Ba) were statistically associated with PCOS risk based on single-metal models. With each natural logarithm transformed (ln) unit increase in blood concentrations of Pb, higher likelihood of PCOS can be found, the adjusted odd ratio (aOR) and 95 % confidence interval (CI) was 1.83 (1.35-2.48), and these for As and Ba were 2.49 (1.86-3.33) and 1.20 (1.04-1.39), respectively. Compared with women at the first tertile group, higher likelihoods of PCOS among women in the second and third tertiles of the Pb group were observed, aORs and 95 % CIs were 1.81 (1.22-2.68) and 2.08 (1.42-3.04), respectively; and higher likelihoods of PCOS among women in the third tertiles of As and Ba group were also observed, the aORs and 95%CIs were 2.83 (1.93-4.15) and 1.89 (1.32-2.72), respectively. BKMR analysis also showed a statistically significant and positive joint effect of five metals on PCOS risk when the blood levels of five metals were all above the 55th percentile compared with their median levels, and As (100 %) and Pb (67.44 %) were the major contributors to the association. The blood As levels were positively associated with the luteinizing hormone (LH) levels and LH/FSH (follicle-stimulating hormone) ratio values, the blood Ba levels were negatively associated with the FSH levels, and the blood Pb levels were positively associated with the fasting insulin levels and homeostasis model assessment of insulin resistance (HOMA-IR) values.

CONCLUSIONS

Our results suggest a positive association between exposure to multiple toxic metals (Pb, Hg, As, Ba and Cd) and PCOS risk. As and Pb were the major contributors, evaluated either as a single agent or metal mixture; and Pb, As, and Ba were associated with different parameters of the clinical PCOS phenotype. Additional studies are warranted to confirm these associations, particularly regarding the synergistic effect of toxic metals.

Assessment of Serum Elements Concentration and Polycystic Ovary Syndrome (PCOS): Systematic Review and Meta-analysis

Change in the levels of trace elements has been linked with PCOS pathogenesis by various studies, whereas some had reported no such association. Therefore, in order to evaluate association of eleven trace element (Cu, Zn, Cr, Cd, Se, Mn, Fe, Mg, Co, Ni and Pb) serum concentration with PCOS pathogenesis, current systematic review and meta-analysis has been carried out. Literature search was conducted using PubMed, Central Cochrane Library, Google Scholar and Science Direct databases with appropriate keywords. Studies published upto 3rd of September were evaluated for eligibility with suitable inclusion and exclusion criteria. Only case-control studies examining the association of serum trace element concentrations between PCOS cases and controls were selected. Present meta-analysis identified 32 articles with 2317 PCOS and 1898 controls. The serum Cu (MD = 15.40; 95% CI = 4.32 to 26.48; p = 0.006), Co (MD = 0.01; 95% CI = 0.01 to 0.02; p = 0.000), Cr (MD = 0.04; 95% CI = 0.00 to 0.07; p = 0.03) and Fe (MD = 12.98; 95% CI = 5.87-20.09; p = 0.0003) concentration is significantly higher, while lower concentration has been observed for Se (MD =  - 0.99; 95% CI =  - 1.31 to - 0.67; p = 0.000) and Mg (MD =  - 223.41; 95% CI =  - 391.60 to - 55.23; p = 0.009) among women with PCOS in comparison with the healthy group. Concentration of other elements which were analysed is not significantly related to PCOS. In short, PCOS women has higher serum concentrations of Cu, Co, Cr and Fe and lower concentrations of Se and Mg. Studies with sub-population of obese, non-obese and with and without insulin resistance are important to understand the pathomechanism of these elements in the syndrome.

Evaluation of trace-element contamination from serum collection tubes used by the California Biobank Program

BACKGROUND

Serum samples archived by the California Biobank Program (CBP) can be a valuable resource to researchers with multiple benefits: affordability, relatively large sample sizes, and racial and geographical representativeness. However, there has been little attention given to the reliability of CBP samples for trace-element analysis. The objectives of this study are to estimate the contamination levels from the serum separation tubes (SST, BD 367983) utilized by the CBP for 13 trace elements (Cr, Mn, Co, As, Se, Sr, Mo, Cd, Sb, Hg, Tl, Pb and U) and to evaluate the feasibility of the use of CBP serum samples for biomonitoring trace elements in human body.

METHODS

Serum separation tubes were tested using deionized (DI) water and whole blood and compared with two alternative sampling devices, plasma separation tubes (PST, BD 365047) and acid-cleaned blood tubes (ABT, BD 367856).

RESULTS AND CONCLUSIONS

The leaching tests for SSTs with DI water demonstrated that detectable levels of Cr, Mn, Co, Sr, Sb, Pb and U were measured, while Sb was elevated. Tests of PSTs also revealed contamination of Mn, Co, Sr and Sb, with Co and Sr being much higher than those found from SSTs. As a more direct approach to estimate trace element contamination, a 45-day time series was conducted using human blood. The differences in elemental concentrations leached into serum/plasma was not considerable between the three types of sampling tubes for Cr, As, Se, Mo, Cd, Hg and Tl. However, SSTs had far greater concentrations than the ABTs for Mn, Co, Sr, Sb and U. For Co and Sr, the PSTs had higher concentrations throughout the experiment than both ABTs and SSTs. Pb showed lower concentrations from the PSTs than the other tubes; we speculate this may be due to re-suspension of settled cellular materials that are elevated in Pb, or re-dissolution of Pb from these materials. Trace-element measurements from 200 samples archived by the CBP using SSTs suggest that SST contamination was negligible for Se and Mo. For Mn, As, Sr, Cd and Hg, based on our leaching results, only a fraction of these samples had considerably high concentrations (e.g., > 10×) compared to the contamination from the SST. For Cr, Co, Sb, Tl, Pb and U, analyte levels were too low in most samples compared to the contamination from the SSTs. Our study also demonstrated that the PSTs could be a "cleaner" alternative to SSTs for analytes such as Cr, As, Cd, Hg, Tl, Pb and U.

Zinc, Copper, Magnesium Levels in Polycystic Ovarian Syndrome Patients

Background:

Background: Polycystic ovarian syndrome (PCOS) is one of the most common endocrine diseases and the status of trace elements is not clear.

Aim and Objectives:

Aim and Objectives: In the present cross-sectional study, the potential relationships between serum levels of zinc, copper, magnesium and PCOS were explored.

Materials and Methods:

Materials and Methods: One hundred participants with PCOS and 100 healthy controls were studied. They were in the age group (15-35 years) with the same socio-demographic characteristics. Blood samples were drawn to estimate the levels of serum zinc, copper, magnesium by autoanalyzer.

Results:

Results: Serum zinc and magnesium levels were found significantly higher among the study group as compared to the control group. Serum copper levels were significantly lower in the study group. Among the PCOS women, serum copper levels were significantly correlated with age and BMI. Serum magnesium and zinc levels had a maximum area under the ROC curve and the high discriminating power of serum magnesium correlated with zinc levels for PCOS.

Conclusion:

Conclusion: These results suggest that trace elements have a role in the pathogenesis of PCOS and their possible supplementation may have a role in the management of PCOS.

Levels of Trace Elements in Erythrocytes as Endocrine Disruptors in Obese and Nonobese Women with Polycystic Ovary Syndrome

Introduction: Polycystic ovary syndrome (PCOS) is one of the most commonly recognized endocrinopathies in women. The literature lacks clear data that allow any meaningful conclusions to be drawn about the influence of trace elements in erythrocytes on the biochemical parameters of PCOS. Materials and methods: This study was conducted among 47 women meeting the Rotterdam criteria for the diagnosis of polycystic ovary syndrome. The research groups included women with PCOS with different BMI values (body mass index): obese women with PCOS (PCOS with BMI ≥ 30, mean BMI index 35.4 ± 4.4 kg/m²), nonobese PCOS women (PCOS with BMI < 30, mean BMI index 25.2 ± 2.8 kg/m²), and healthy control group (CG) with a mean BMI of 23.57 ± 0.9 kg/m². The contents of trace elements in erythrocytes were determined with an inductively coupled plasma atomic emission spectrometer. Results: The only trace element showing significant differences in concentration between the studied groups was nickel (Ni). The level of nickel in the obese women with PCOS (BMI ≥ 30) was significantly higher than in nonobese women (BMI < 30). The content of other trace elements in erythrocytes did not differ significantly between the studied groups. Several significant correlations were found within each of the studied PCOS groups: in the group of obese women, the content of zinc (Zn) in erythrocytes positively correlated with prolactin, the content of magnesium (Mg) positively correlated with testosterone, and the content of manganese (Mn) negatively correlated with thyroid-stimulating hormone. In the group of nonobese women, Zn content correlated positively with testosterone, Ni with luteinizing hormone (LH) and estradiol, and Mg negatively correlated with estradiol. Conclusions: The relationship between the level of trace elements and the level of hormones suggests that, in obese women with PCOS, nickel may play a role in inhibiting the processes of folliculogenesis and ovulation. Research on trace elements and their relationship to ovulatory cycles and the development of PCOS may contribute to reducing the consequences of PCOS and, therefore, should be extended.

Antioxidant status in relation to heavy metals induced oxidative stress in patients with polycystic ovarian syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a global health concern for women of reproductive age, as 6.5% of women worldwide are affected by this syndrome. PCOS is marked by hyperandrogenism, anovulation, menstrual abnormalities, and polycystic ovaries. Metals such as arsenic, cadmium, lead and mercury are considered to be systemic toxicants/human carcinogens and seem to have devastating effects on humans, even at minimal exposures. One of the probable aetiological factors for PCOS has been identified as oxidative stress. In view of the probable associations among oxidative stress, metal toxicity and PCOS, the present study examined the role of heavy metals in the generation of oxidative stress among females. This prospective study included 106 women (56 women diagnosed with PCOS and 50 women who were not diagnosed with PCOS as control women). There were no significant differences in the sociodemographic characteristics between the two groups except for the irregularity of menses and the presence of acne. The serum As, Cd, Pb, and Hg levels increased and the serum glutathione (GSH) and superoxide dismutase (SOD) levels diminished significantly in the PCOS group compared to the control group at P < 0.001. The SOD levels were negatively correlated with the As and Pb levels at P < 0.05. Additionally, the PCOS group exhibited a strong negative correlation between the GSH and As levels (P < 0.01), GSH and Pb levels (P < 0.05) and GSH and Hg levels (P < 0.01). Furthermore, the As levels were positively correlated with increased levels of Cd, Pb and Hg among PCOS women. Significant positive correlations were observed between Pb and Cd and between Cd and Hg at P < 0.001. The outcome of the study provides clear insight into the role of metal-induced oxidative stress, which plays a vital role in the pathophysiology underlying PCOS and suggests the use of these markers as prognostic tools to reduce the consequences of high-risk exposure to these metals among females.

Associations between blood heavy metal(loid)s and serum heme oxygenase-1 in pregnant women: Do their distribution patterns matter?

The relationship between heavy metal(loid)s exposure and oxidative stress damage is a matter of research interest. Our study aimed to investigate the distribution patterns of the nine heavy metal(loid)s in blood of pregnant women, including four toxic heavy metal(loid)s [arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg)] and five typical heavy metal(loid)s [manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn), and selenium (Se)] in blood. Blood samples of 348 women were collected and their concentrations in the serum (sr) and blood cells (bc) were measured, as well as serum heme oxygenase-1 (HO-1) (an oxidative stress marker). Total blood (tb) concentrations of these metal(loid)s and serum-to-blood cell concentration ratios (sr/bc) were further calculated. We found Cu mainly accumulated in the serum compared to the blood cells with Cu^sr/bc = 2.30, whereas Co, Se, and As evenly distributed between these two fractions. Other metal(loid)s mainly concentrated in the blood cells. Co^sr, Cu^sr, Cu^bc, Mn^bc, Zn^bc, Cd^bc, Co^tb, Cu^tb, Mn^tb, Zn^tb, Cd^tb, and Cu^sr/bc were negatively associated with serum HO-1, whereas As^sr, As^bc, As^tb, Zn^sr/bc, Cd^sr/bc, and Hg^sr/bc were positively, indicating of their potential toxicity. We concluded that the distribution patterns of blood heavy metal(loid)s, in particular for Cd, Hg and Zn, which either increased in serum or decreased in blood cells, might be associated with elevated serum oxidative stress, should be considered in environmental health assessments.

The Content of Minerals in the PCOS Group and the Correlation with the Parameters of Metabolism

Polycystic ovary syndrome (PCOS) is a common disease in women of childbearing age. It is characterized by excessive androgen production, ovulation disorders, and developing metabolic syndrome. The aim of the study was to check whether selected minerals were related to the pathophysiological mechanisms of PCOS. The concentrations of minerals were determined using an inductively coupled atomic plasma-emission spectrometer (ICP-AES Jobin Yvon JY-24). Blood samples from PCOS and control women were collected, processed, and digested with a microwave system in women with PCOS with and without insulin resistance and in the control group. It was found: zinc (Zn)-10.14 ± 2.11, 9.89 ± 1.44 and 10.30 ± 1.67; nickel (Ni) 0.001 ± 0.0009, 0.001 ± 0.0006 and 0.002 ± 0.00001; iron (Fe) 868.0 ± 155.8, 835.3 ± 156.4 and 833.0 ± 94.6; manganese (Mn) 0.017 ± 0.006, 0.017 ± 0.008 and 0.020 ± 0.009; copper (Cu) 0.714 ± 0.129, 0.713 ± 0.114 and 0.761 ± 0.146; magnesium (Mg) 48.4 ± 8.3, 50.0 ± 8.4 and 45.3 ± 10.7; sodium (Na) 374.3 ± 84.3, 396.3 ± 66.6 and 367.9 ± 88.9; potassium (K) 2541.8 ± 330.9, 2409.6 ± 347.1 and 2336.9 ± 211.4 (µg/g). Some micronutrient deficiencies may have a negative effect on the lipid profile in PCOS patients (Ni, Na). Further studies are needed to better understand dependencies.

Serum Copper Level and Polycystic Ovarian Syndrome: A Meta-Analysis

INTRODUCTION

The association of serum copper with polycystic ovarian syndrome (PCOS) has been studied for years, but no definite conclusion is drawn. Therefore, we conducted a meta-analysis to investigate serum copper concentrations in PCOS subjects compared with healthy controls.

METHODS

Electronic search was performed in PubMed, Google Scholar, and Scopus up to June 30, 2020, without any restriction. Standardized mean differences (SMDs) with corresponding 95% CIs in serum copper levels were employed with random-effects model. I2 was applied to evaluate heterogeneity among studies.

RESULTS

Nine studies, measuring plasma copper levels in 1,168 PCOS patients and 1,106 controls, were included. Pooled effect size suggested serum copper level was significantly higher in women with PCOS (SMD = 0.51 μg/mL, 95% CI = [0.30, 0.72], p < 0.0001). The overall heterogeneity was not connected with subgroups of the country, but derived from the opposite result of 1 study.

CONCLUSION

Our research generally indicated circulating copper level in PCOS sufferers was significantly higher than normal controls. Large-scale studies are still needed to elucidate the clear relation between copper status and etiology of PCOS.

Potential environmental toxicant exposure, metabolizing gene variants and risk of PCOS-A systematic review

Exposure of environmental toxicants such as potentially toxic metals and pesticides have largely been attributed to produce adverse effects on general women's health and to be more precise on the reproductive system. In order to explore exposure of toxicants and metabolizing gene variants as risk factor for polycystic ovarian syndrome (PCOS), literature search was carried out using the databases PubMed, Central Cochrane Library, Google Scholar, Science Direct with appropriate keywords upto 6 December 2020. While most of the studies indicate higher serum Cu concentration and lower concentration of Mn as risk factor, studies also report presence of higher pesticide concentration in PCOS women. Genes such as MTHFR, CYPs participate in the metabolism of toxicants and may show different response due to underlying genetic variants. Thus, toxicant exposure are to some extent responsible for the pathogenesis of syndrome through oxidative stress and endocrine disruption, but the susceptibility may vary due to the underlying genetic polymorphism of the exposed population.

The Role of Trace Elements in Pseudoexfoliation Syndrome: A Cross-sectional Study

Purpose

Pseudoexfoliation syndrome (PXF) is an age-related condition, characterized by deposition of whitish flake-shaped materials in the anterior segment of the eye. Although it occurs all over the world, a considerable racial variation exists. According to the high frequency of PXF in Iran and the importance of prevention and early treatment, we evaluated the plasma level of iron, zinc, copper, and magnesium in patients with PXF.

Methods

In this study, 83 individuals were enrolled; 40 patients with cataract and PXF as the case group and 43 age- and sex-matched individuals with cataract but without PXF as the control group. The serum levels of the mentioned microelements were compared in two groups.

Results

In the case group, 25 (62.5%) male and 15 (37.5%) female subjects participated. In the control group, the corresponding figures were 22 (51.2%) and 21 (48.8%), respectively. The mean age of the case group was 66.07 ± 9.46 and that for the control group was 66.88 ± 8.04 years. Regarding the case group, the serum levels of iron, zinc, copper, and magnesium were 60.58 ± 21.04, 84.7 ± 14.37, 120.23 ± 14.43, and 2.11 ± 0.23, respectively. These serum levels in the control group were 89.07 ± 26.06, 97.51 ± 17.42, 123.33 ± 19.01, and 2.14 ± 0.16. The serum levels of iron and zinc were significantly lower in the case group than the control group (P< 0.0001); however, such a difference was not observed in terms of copper and magnesium serum levels.

Conclusion

Our study demonstrated that the serum iron and zinc levels were lower in PXF patients. Nutritional deficiency may be a cause of zonular weakness in these patients. Heme is a cofactor for the enzyme which contributes to the biosynthesis of fibrillin, the major protein in zonular fibers. Therefore, iron can play a substantial role in the biosynthesis of the fibrils and also in the zonular stability.

Associations between blood cadmium and endocrine features related to PCOS-phenotypes in healthy women of reproductive age: a prospective cohort study

BACKGROUND

Cadmium is an endocrine disrupting chemical that affects the hypothalamic-pituitary-gonadal axis. Though evidence suggests its potential role in altering androgen synthesis and metabolic pathways that are characteristic of polycystic ovary syndrome (PCOS), its relation in healthy women of reproductive age is largely unknown. As women with mild sub-clinical features of PCOS who do not meet the diagnostic criteria of PCOS may still experience reduced fecundability, investigating associations between cadmium and PCOS-phenotypes among healthy women may provide unique insight into the reproductive implications for many on the PCOS spectrum. Therefore, the objective of this study was to evaluate associations between cadmium and androgens, anti-Müllerian hormone (AMH), and metabolic markers in women of reproductive age.

METHODS

This was a prospective cohort study of 251 healthy premenopausal women without self-reported PCOS (mean age 27.3 years and BMI 24.1 kg/m²). Cadmium was measured in blood collected at baseline. Reproductive hormones and metabolic markers were measured in fasting serum 8 times per menstrual cycle for 2 cycles. Linear mixed models and Poisson regression with a robust error variance were used to examine associations between cadmium and reproductive hormones and metabolic markers and anovulation, respectively.

RESULTS

Median (interquartile range) blood cadmium concentrations at baseline were 0.30 (0.19-0.43) µg/L. Higher levels of testosterone (2.2 %, 95 % confidence interval [CI] 0.4, 4.1), sex hormone-binding globulin (2.9 %, 95 % CI 0.5, 5.5), and AMH (7.7 %, 95 % CI 1.1, 14.9) were observed per 0.1 µg/L increase in cadmium concentrations. An 18 % higher probability of a mild PCOS-phenotype (95 % CI 1.06, 1.31), defined by a menstrual cycle being in the highest quartile of cycle-averaged testosterone and AMH levels, was also found per 0.1 µg/L increase in cadmium levels. No associations were observed for insulin and glucose. These findings were consistent even after analyses were restricted to non-smokers or further adjusted for dietary factors to account for potential sources of exposure.

CONCLUSIONS

Overall, among healthy reproductive-aged women, cadmium was associated with endocrine features central to PCOS, but not with metabolic markers. These suggest its potential role in the hormonal milieu associated with PCOS even at low levels of exposure.

Associations of age at natural menopause and occupations in Chinese female workers: A cross-sectional study

AIMS

To investigate the impact of occupation types on age at natural menopause.

METHODS

This is a nation-wide cross-sectional study based on 17,948 female workers aged over 40, who come from different industries or organizations. A face-to-face standardized questionnaire was conducted in all participants with the help of occupational hygienists. Occupational titles were coded according to the International Standard Classification of Occupations (2008) (ISCO08). Cox regression model was used to assess the association between each independent occupation and menopausal timing. Models were adjusted for marriage, education, average annual family income, parity, cigarette smoking, alcohol consumption.

RESULTS

Higher risks of earlier age at natural menopause was found among legislators and senior officials (ISCO Minor group:111, HR = 2.328, P < 0.001), among other health associated professionals (ISCO Minor group: 325, HR = 1.477, P = 0.003), the workers involved in mining and mineral processing (ISCO Minor group: 811, HR = 1.515, P = 0.048) and metal processing and finishing (ISCO Minor group: 812, HR = 1.722, P < 0.001). Reduced risks of earlier age at natural menopause, including: finance professionals (ISCO Minor group: 241, HR = 0.751, P = 0.021), manufacturing and construction supervisors (ISCO Minor group: 312, HR = 0.477, P = 0.002), administrative and specialized secretaries (ISCO Minor group: 334, HR = 0.788, P = 0.045), cleaners and helpers (ISCO Minor group: 911, HR = 0.633, P = 0.01).

CONCLUSIONS

This is the first study to address the influence of occupation types on reproductive aging, showing some specific occupations could be associated with age at natural menopause. Further investigations are necessary to clarify whether it is chance finding or a true association.

Nutritional and dietary aspects in polycystic ovary syndrome: insights into the biology of nutritional interventions

Polycystic Ovary Syndrome (PCOS) is a complex endocrine disorder, which affects 5-17% of reproductive age women and is often associated with obesity and metabolic impairment. Common treatment strategies are based on exercise, diet and nutrient supplementation since PCOS is often linked with obesity and metabolic impairment. Studies have recommended that nutrition is a key factor in the health maintenance of women with PCOS, however, little is known about the subject in the context of such a disease. This narrative review aims to identify dietary and nutritional aspects of PCOS and discuss the role of nutrients in management of polycystic ovary syndrome in view of clinical trials.

Are Heavy Metal Exposure and Trace Element Levels Related to Metabolic and Endocrine Problems in Polycystic Ovary Syndrome?

This study aimed to determine the relationship between the metabolic and endocrinological pathologies in polycystic ovary syndrome (PCOS) and the levels of arsenic, chromium, cadmium, lead, mercury, antimony, zinc, and copper to evaluate the relationship of these toxic metals with inflammatory/oxidative parameters. This study included a total of 154 patients (84 with PCOS, 70 healthy volunteers). Metabolic and endocrine parameters and arsenic, chromium, cadmium, lead, mercury, antimony, zinc, and copper serum levels of the patients were compared between the groups. Considering the action mechanism of toxic metals, serum malondialdehyde (MDA), superoxide dismutase (SOD), serum total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tumor necrosis factor-alpha (TNFα), and high-sensitivity C-reactive protein (HsCRP) levels were determined. Serum TAS (p = 0.002), OSI (p = 0.006), SOD (p = 0.006), zinc (p = 0.010), and copper (p = 0.030) values were statistically lower whereas TOS (p = 0.008), MDA (p < 0.001), HsCRP (p < 0.001), TNFα (p < 0.001), antimony (p < 0.001), cadmium (p < 0.001), lead (p < 0.001), and mercury (p < 0.001) levels were significantly higher in the PCOS group than those determined in the control group. Antimony was positively correlated with fasting glucose (FG) and HOMA-IR while cadmium, in addition to FG and HOMA-IR, positively correlated with insulin and lead had a positive correlation only with FG (p < 0.05). Also, these three heavy metals correlated positively with some oxidative system and inflammatory parameters and negatively with the antioxidant system parameters (p < 0.05). In conclusion, heavy metal exposures in PCOS may be related to insulin resistance and hirsutism through oxidative and inflammatory mechanisms. This approach can be used to identify the risky patient group and to develop new treatment modalities.

Update of the risk assessment of nickel in food and drinking water

The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post-implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL 10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 μg/kg bw. Eczematous flare-up reactions in the skin elicited in nickel-sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest-observed-adverse-effect-level of 4.3 μg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel-sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.

The Role of Zinc in Selected Female Reproductive System Disorders

Zinc is an essential microelement that plays many important functions in the body. It is crucial for the regulation of cell growth, hormone release, immunological response and reproduction. This review focuses on its importance in the reproductive system of women of reproductive and postmenopausal ages, not including its well described role in pregnancy. Only recently, attention has been drawn to the potential role of zinc in polycystic ovary syndrome (PCOS), dysmenorrhea, or endometriosis. This review is mainly based on 36 randomized, controlled studies on reproductive, pre- and post-menopausal populations of women and on research trying to explain the potential impact of zinc and its supplementation in the etiology of selected female reproductive system disorders. In women with PCOS, zinc supplementation has a positive effect on many parameters, especially those related to insulin resistance and lipid balance. In primary dysmenorrhea, zinc supplementation before and during each menstrual cycle seems to be an important factor reducing the intensity of menstrual pain. On the other hand, little is known of the role of zinc in endometriosis and in postmenopausal women. Therefore, further studies explaining the potential impact of zinc and its supplementation on female reproductive system would be highly advisable and valuable.

Copper affects steroidogenesis and viability of human adrenocortical carcinoma (NCI-H295R) cell line in vitro

Copper is an environmental risk factor, which has various effects on reproductive endocrinology. In this study human adrenocortical carcinoma (NCI-H295R) cell line was used as an in vitro biological model to study the effect of copper sulfate (CuSO₄.5H₂O) on steroidogenesis and cytotoxicity. The cell cultures were exposed to different concentrations (3.90, 62.50, 250, 500, 1000 µM) of CuSO₄.5H₂O and compared to control group (medium without CuSO₄.5H₂O). Cell viability was measured by the metabolic activity assay. Quantification of sexual steroid production directly from the medium was performed by ELISA assay. Following 48 h culture of NCI-H295R cell line in the presence of CuSO₄.5H₂O a dose-dependent depletion of progesterone release was observed even at the lower concentrations of CuSO₄.5H₂O. The lowest levels of progesterone were detected in groups with the higher doses (≥ 250 µM) of CuSO₄.5H₂O, which elicited significant cytotoxic action. Testosterone production decreased significantly, and this decline was more prominent in comparison to that of progesterone. The lowest release of testosterone was recorded at 1000 µM of CuSO₄.5H₂O. The cytotoxic effect of CuSO₄.5H₂O was evident at all concentrations used in the study. The presented data suggest that copper has detrimental effects on sexual steroid hormones and consecutively on reproductive physiology.

Association of blood metal exposure with testosterone and hemoglobin: A cross-sectional study in Hangzhou Birth Cohort Study

BACKGROUND

Few epidemiological studies have investigated associations of exposure to multiple metals with testosterone homeostasis and erythropoiesis, especially for the pregnant women.

METHODS

Among all the 1644 participants enrolled in Hangzhou Birth Cohort Study (HBCS) at baseline, a total of 918 pregnant women with complete data of interest were analyzed. The whole blood metals levels were examined by inductively coupled plasma mass spectrometry (ICP-MS), and serum testosterone level was evaluated by chemiluminescent microparticle immunoassay (CMIA), and erythropoietic parameters values were extracted from medical record. Multivariable linear regression models were applied to estimate the relationships between metals levels and testosterone level, and between metals levels and erythropoietic parameters, and potential confounders were adjusted.

RESULTS

Single metal model analysis revealed a significant association of blood As, Mn and Pb level with serum testosterone level. After controlling for multiple testing, the dose-response trend with statistical significance (FDR-adjusted p trend <0.05) was observed across tertiles of Pb with testosterone. This association, when by stratified by gender, remained in pregnant women with a male fetus but did not reach significant in those with a female fetus. Furthermore, blood Pb level was positively associated with red blood cell counts, hemoglobin level and hematocrit. Serum testosterone level was positively associated with red blood cell counts, hemoglobin level and hematocrit. Mediation analyses indicated that testosterone might act as a mediator in the association between Pb exposure and erythropoietic parameters.

CONCLUSIONS

Serum testosterone level and hemoglobin level was positively related to blood Pb level among Chinese pregnant women, and testosterone might mediate the effect of Pb exposure on hemoglobin. Additional prospective studies are warranted to confirm the causality.

Status of Serum Copper, Magnesium, and Total Antioxidant Capacity in Patients with Polycystic Ovary Syndrome

This study evaluates serum copper and magnesium and total antioxidant capacity levels in PCOS patients. In this regard, the probable association of copper and magnesium with total antioxidant capacity (TAC) was investigated. In total, 150 women (60 PCOS patients and 90 healthy subjects) participated in this case-control study. PCOS was diagnosed according to the Rotterdam criteria (2003). Serum Cu, Mg, Ca, TAC, insulin levels, and insulin resistance indices were determined. Insulin was measured using ELISA methods. Serum Cu and Mg levels were measured by an atomic absorption spectrophotometer and the Xylidyl Blue method respectively. The correlations between the parameters were analyzed using the Spearman correlation test. Serum Cu level was significantly higher while TAC was significantly lower in the PCOS patients than those in the controls (p = 0.019 and p = 0.002 respectively). No significant difference was detected between the two groups in terms of serum Mg and Ca levels and Ca/Mg ratio. In insulin-resistant PCOS subjects, there was a negative correlation between Mg levels and homeostatic model assessment for insulin resistance (r = - 0.449, p = 0.006) but a positive correlation between Mg levels and quantitative insulin sensitivity check index (r = 0.480, p = 0.003). A negative correlation also existed between Mg levels and TAC in non-insulin-resistant PCOS patients (r = - 0.407, p = 0.04). According to the results, copper and magnesium seem to contribute to oxidative stress and insulin resistance in PCOS patients. Therefore, to prevent long-term metabolic complications in PCOS women, it is recommended that these elements be routinely monitored. Also, significantly lower levels of serum TAC in PCOS patients than in normal women may suggest increased oxidative stress in such patients.

Serum Trace Elements in Patients With Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Polycystic ovary syndrome (PCOS) is reported to be associated with certain trace elements. However, previous data are inconsistent and potentially biased due to small sample sizes. The potential utility of trace element levels for screening of PCOS remains to be established. The aim of this meta-analysis was to investigate the potential relationships between PCOS and serum levels of zinc (Zn), copper (Cu), magnesium (Mg), iron (Fe) and ferritin. We carried out a literature search of PubMed, EMBASE, and Web of Science for relevant cross-sectional/case-control studies published prior to October 2019. Random-effect models were used to estimate the overall standard mean differences (SMDs) between PCOS and healthy control subjects. The screening value of potential microelement biomarkers for PCOS was assessed using the receiver operating characteristic (ROC) curve. Twenty-one studies featuring 2,173 women with PCOS and 1,897 healthy women were selected for analysis. Our results showed that Cu and ferritin levels were significantly higher in women with PCOS than healthy controls, with SMDs of 0.52 [95% confidence interval (CI): 0.38-0.67, I² = 47.6%] and 1.05 (95% CI: 0.25-1.86, I² = 97.0%), respectively. The serum ferritin concentration was distinguished as a potential biomarker for PCOS based on the high area under ROC curve value of 0.71 (95% CI: 0.57-0.86). Although we did not identify a statistical association between serum Zn concentration and PCOS overall, the concentration of Zn in PCOS women with insulin resistance (IR) was lower than that in healthy women (SMD = -0.89, 95% CI: -1.73 to -0.06). Furthermore, the concentrations of Mg (SMD = 0.31, 95% CI: -0.32-0.94, I² = 95.4%) and Fe (SMD = -0.59, 95% CI: -1.29-0.12, I² = 97.2%) were not statistically significant between the PCOS and control groups. We generated hypothetical pathways for associations among serum Cu, ferritin and PCOS. The serum concentrations of both Cu and ferritin were significantly higher in women with PCOS, and ferritin was identified as a potential early indicator for PCOS screening. Further studies are essential to determine the specific underlying mechanisms.

Assessment of Gender Effects and Reference Values of Mane Hair Trace Element Content in English Thoroughbred Horses (North Caucasus, Russia) Using ICP-DRC-MS

The objective of the present study was assessment of gender differences in hair trace element content in English Thoroughbred horses (North Caucasus, Russia) using ICP-DRC-MS and calculation of the reference values. Trace element content in mane hair of 190 stallions and 94 mares (3-7 years old) bred in North Caucasus (Russia) was assessed using inductively coupled plasma mass spectrometry. Mane hair Co, Cr, Mn, Li, Si, and Sr levels in mares exceeded those in stallions by 77%, 63%, 64%, 42%, 39%, and 64%, respectively. Hair Fe and Si content was nearly twofold higher in female horses as compared to the males. Only hair Zn content was 5% higher in stallions as compared to mares. In addition, mares were characterized by 63%, 65%, 29%, and 40% higher levels of As, Pb, Sn, and Ni levels in hair as compared to the respective values in stallions. In turn, hair Al and Hg were more than twofold higher in mares than in stallions. The reference intervals of mane hair content (μg/g) for Co (0.006-0.143), Cr (0.028-0.551), Cu (4.17-6.84), Fe (10.11-442.2), I (0.026-3.69), Mn (0.551-12.55), Se (0.108-0.714), Zn (97.43-167), Li (0.011-0.709), Ni (0.060-0.589), Si (0.665-29.12), V (0.006-0.584), Al (1.98-168.5), As (0.006-0.127), Cd (0.002-0.033), B (0.494-16.13), Pb (0.018-0.436), Sn (0.002-0.144), Sr (1.0-9.46), and Hg (0.0018-0.017) in the total cohort of horses were estimated using the American Society for Veterinary Clinical Pathology Quality Assurance and Laboratory Standard Guidelines. The reference intervals were also estimated for stallions and mares bred in North Caucasus (Russia) and may be used for interpretation of the results of hair trace element analysis in horses.

Zinc status and polycystic ovarian syndrome: A systematic review and meta-analysis

Several studies have investigated serum zinc levels in patients with polycystic ovarian syndrome (PCOS), but the results of these studies remain inconclusive. Therefore, to derive a more precise estimation, we conducted a meta-analysis to investigate serum zinc concentrations in women with PCOS in comparison with healthy subjects. Electronic search was performed in PubMed, Scopus, and Google scholar up to April; 4, 2018 without any restriction. Eligible studies that evaluated the levels of zinc status in subjects with PCOS were included. Weighted mean differences (WMDs) with corresponding 95% CIs in serum zinc levels were initially estimated using a random-effects model. Eight studies, measuring circulating zinc levels in 552 PCOS and 464 control subjects, were included. Pooled effect size suggested that serum zinc levels in women with PCOS were not statistically different than their controls (WMD = -4.43 mg/dL; 95% CI = [-10.30, 1.44]; P = 0.139). Exclusion of one study revealed that women with PCOS significantly have lower serum zinc levels compared to healthy controls (WMD: -6.60 mg/dL; 95% CI = [-12.43, -0.76], P = 0.027). Our study indicated that circulating zinc levels in women with PCOS were significantly lower than those in healthy controls when detailed analysis is conducted. Large scale studies are needed to elucidate clear relation between zinc status and etiology of PCOS.

Polycystic ovarian syndrome: Environmental/occupational, lifestyle factors; an overview

Polycystic ovary syndrome (PCOS) is a multifaceted disease of women with infertility that has diverse etiologic factors. Some women may have only a few PCOS-linked symptoms or mild symptoms, whereas others will have severe or all PCOS-linked symptoms. Therefore, PCOS symptoms can differ among women. PCOS is a state of hormonal imbalance, excess terminal hair (hirsutism), hair loss (alopecia), menstruation impairments, metabolic disorders, and cystic appearance on the ovaries. The cysts hamper ovulation, thus reducing the ability of women to become pregnant and result in infertility. The available data suggest that PCOS might originate in utero and the phenotypic appearance of PCOS symptoms may be developed in later life, which could be linked with host factors (endogenous) and exogenous factors like lifestyle, and dietary, environmental or occupational factors. Based upon the available information, it can be postulated that prenatal exposure to excessive androgens might be responsible for androgenization of the fetus, which in turn may alter the program of differentiating target tissues and the phenotypic characteristics of PCOS can be persuaded by exposure of female offspring to various endogenous and exogenous factors at later life. Genetic/host and environmental/lifestyle factors might be related to the pathophysiology of PCOS after prenatal exposure to androgen. Additional studies are necessary to understand the exact mechanism responsible for the manifestation of PCOS because it is a very important issue in female reproduction.

High copper levels in follicular fluid affect follicle development in polycystic ovary syndrome patients: Population-based and in vitro studies

Although the adverse effects of copper overexposure on the liver, kidney, spleen and intestinal organs are well known, information about the impact of copper toxicity on human reproduction is limited. A total of 348 infertile patients were enrolled in our present study, including 89 with polycystic ovary syndrome (PCOS), 145 with fallopian tube obstruction and 114 controls. The follicular fluid concentrations of 22 trace elements were measured by inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis was used to identify trace element profile alterations in different groups. The mRNA levels of steroidogenesis-related genes were measured by real-time PCR. Our results showed that the trace element profile in follicular fluid was obviously altered in PCOS patients. Copper concentrations were significantly (p < .05) higher in the PCOS group than in the other two groups. Increased copper levels in follicular fluid were associated with a higher number of retrievable oocytes in the PCOS group (B = 1.785, p = .001) but a lower rate of high-quality embryos (B = -6.360, p = .050). Moreover, follicular fluid copper levels were positively correlated with follicular fluid progesterone levels (r = 0.275, p = .010) and testosterone levels (r = 0.250, p = .022). Cultured human granulosa cells overexposed to copper showed significantly (p < .05) increased estradiol secretion and decreased testosterone levels. Real-time quantitative PCR revealed a significant (p < .05) increase in CYP19A1 and HSD3b mRNA expression. Our results indicate that increased copper levels in follicular fluid could affect follicle development in PCOS patients, and the mechanism may be related to copper-induced abnormalities in steroidogenesis.

Chromium supplementation does not improve weight loss or metabolic and hormonal variables in patients with polycystic ovary syndrome: A systematic review

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age, and recently, chromium was discussed as an adjuvant way to manage it. Herein, a systematic review was conducted which centered on the effects of chromium on ovarian physiology with a focus on body mass index, as well as hormonal and metabolic dysfunctions in women suffering from PCOS. This review was performed using the guidelines from Preferred Reporting Items for Systematic Reviews. Clinical trials investigating chromium in women with PCOS with outcome measures related to metabolic and hormonal status were included. The search was conducted using PubMed, Scopus, and Google Scholar databases for clinical trials in the English language from the inception of the resources until May 2017 with the terms: chromium, chromium picolinate, CrP, polycystic ovary syndrome, PCOS, and sclerocystic ovary syndrome. The search resulted in 89 articles, and after inclusion and exclusion criteria were applied, 6 articles were selected for analysis. Two studies that evaluated the effect of chromium on body weight or body mass index reported no effect. Another study reported the beneficial effect of chromium on weight reduction. It seems that the effect of chromium in the reduction of blood glucose is insignificant, and results are inconsistent in relation to dyslipidemia. With regard to the effects of chromium on concentrations of sex hormones, a longer duration of treatment is needed to produce significant changes. The articles reviewed demonstrated that chromium supplementation has limited effects on weight reduction, glucose control, lipid profile, and hormonal disturbance of women with PCOS; however, more studies are needed due to the clinical changes observed in patients with PCOS after chromium supplementation.

Safety evaluation of Bon-santé cleanser® polyherbal in male Wistar rats: Further investigations on androgenic and toxicological profile

BACKGROUND

The global increase in acceptance and use of herbal remedies in recent times is still accompanied with poor knowledge of their potential adverse effects and the toxicological implications of their use are underestimated.

METHODS

Bon-santé Cleanser® (BSC), a polyherbal containing Anogeissus leiocarpus, Terminalia ivorensis, Massularia acuminate and Macuna pruriens, is an "energizer and hormone booster". We assessed the effect of BSC on reproductive function after administration for 60 days in male Wistar rats. Rats (150-300 g) were assigned into four groups of 8/group. Control received distilled water (10 ml/kg) while other groups received BSC 250, 500 and 1000 mg/kg/day p.o. respectively. Animals were euthanized by cervical dislocation and samples collected for analysis.

RESULTS

BSC (250 mg/kg) elevated (p < 0.05) follicle stimulating hormone and luteinizing hormone levels respectively. BSC decreased sperm motility and the live-dead ratio at 1000 mg/kg and reduced reproductive hormone at 500 mg/kg and 1000 mg/kg respectively. BSC at 500 mg/kg increased (p < 0.05, F = 3.18-13.21) testicular reduced glutathione level (50.3%) and catalase (43.7%) but not activities of superoxide dismutase, glutathione S-transferase, and malondialdehyde level. Further, BSC influenced Mg, Zn, Cu, P, Mn, Ni and Fe levels (p < 0.05). BSC (1000 mg/kg) decreased testis weight (p < 0.05) and induced mild inflammation characterized by atrophic tubules.

CONCLUSION

Overall, our data suggest BSC at low doses may increase reproductive hormones regulated by FSH and LH as observed in this study. However, BSC administration should be done with caution as it may induce reproductive toxicity in large doses.

Serum Level of Zinc and Copper in Sudanese Women with Polycystic Ovarian Syndrome

The study aimed to evaluate the serum level of zinc and copper in women with polycystic ovarian syndrome (PCOS). A case-control study was conducted at Saad Abualila infertility center (Khartoum, Sudan). The cases were women who had a PCOS based on Rotterdam criteria. The controls were infertile women with no evidence of PCOS. The socio-demographic characteristics and medical history data were gathered using questionnaires. Zinc and copper levels were measured using atomic absorption spectrophotometer. While there was no difference in zinc and copper levels between the two groups (50 women in each arm), mean (SD) of body mass index (BMI) was significantly higher in women with PCOS compared to the controls [28.4 (4.2) vs. 25.6 (5.7) kg/m²; P = 0.006], respectively. There were no significant differences in the level of luteinizing hormone (LH), follicle stimulating hormone (FSH), LH/FSH, prolactin, testosterone, cholesterol, triglycerides and low-density lipoprotein (LDL) between the cases and the controls. In linear regression analyses, none of the investigated factors were associated with PCOS. Zinc and copper were not associated with PCOS in this setting.

Chromium supplementation in women with polycystic ovary syndrome: Systematic review and meta-analysis

AIM

Increasing evidence has suggested that chromium supplementation may improve the clinical symptoms of polycystic ovary syndrome (PCOS), yet the results have been inconsistent. To derive a more precise estimation of the efficacy of chromium, a meta-analysis was performed.

METHODS

Studies published in PubMed, EMBASE and the Cochrane Library up to April 2017 were retrieved. Standardized mean differences (SMD) with 95%CI were calculated for net changes using random-effects or fixed-effects models.

RESULTS

A total of six randomized clinical trials (RCT) with 351 PCOS women were ultimately collected in this meta-analysis. All included RCT were of moderate-high quality. On pooled analysis, insulin resistance was significantly decreased (SMD, -0.84; 95%CI: -1.30 to -0.38; P = 0.0004), while the total testosterone (SMD, 0.36; 95%CI: 0.07-0.65; P = 0.02) and free testosterone (SMD, 0.80; 95%CI: 0.48-1.12; P < 0.00001) were markedly increased in chromium-treated PCOS patients compared with control groups. No significant difference was found in other indexes of insulin metabolism (body mass index, fasting insulin, fasting blood sugar and quantitative insulin sensitivity check index), hormone status (luteinizing hormone, follicle-stimulating hormone and prolactin) and lipid profiles (cholesterol and triglycerides) between the two groups.

CONCLUSION

Supplementation with chromium may not have significant benefits for women with PCOS. More RCT with low heterogeneity, however, are required to corroborate the present findings.

Selenium Administration Alleviates Toxicity of Chromium(VI) in the Chicken Brain

Selenium (Se) can play a protective role against heavy metal toxicity. This experiment aims to evaluate the effect of Se supplementation at different doses on the chicken brains. Oxidative stress was induced in the chicken brains by chromium(VI). A total of 105 Hyland brown male chickens were randomly divided into seven groups, including the control group, poisoned group [6%LD₅₀ K₂Cr₂O₇ body weight (B.W.)], and detoxification groups K₂Cr₂O₇ (6%LD₅₀) + Se (0.31, 0.63, 1.25, 2.50, and 5.00 Na₂SeO₃ mg/kg B.W.) orally in water for 42 days. The chickens were detected by the activities of mitochondrial membrane potential, 2'-benzoyloxycinnamaldehyde, superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), and Ca²⁺-ATPase. Cr(VI) administration caused histopathological damage. In addition, changes in oxidative stress indicators were observed in the chicken's brains. Se supplement increased the levels of GSH, mitochondrial membrane potential (MMP), and Ca²⁺-ATPase and reduced MDA activity in the detoxification groups. However, the high-dose Se supplementation groups of 2.50 and 5.00 mg/kg reduced the activities of GSH, MMP, and Ca²⁺-ATPase; increased the brain-body ratio; and increased SOD activity. In conclusion, Cr(VI) exposure caused oxidative stress. Se exerted a remission effect on toxic responses in the chicken brains. However, a high Se concentration was synergistic to the toxic effect of Cr(VI).

Serum Macroelement and Microelement Concentrations in Patients with Polycystic Ovary Syndrome: a Cross-Sectional Study

Polycystic ovarian syndrome (PCOS) is one of the most common endocrine diseases. However, its pathogenesis is unclear. We aim to explore the potential relationships between serum macroelements/microelements and PCOS. A total of 1137 women were involved in the current study. PCOS was defined according to ESHRE/ASRM, and complete blood samples were collected. Serum macroelements (calcium and magnesium) and microelements (copper, zinc, and iron) were assayed through atomic absorption spectrophotometry. PCOS patients had significantly higher copper concentrations than patients without PCOS (P < 0.001). By contrast, PCOS patients had lower serum calcium levels than patients without PCOS (P < 0.001). No significant differences were observed in the levels of serum zinc, magnesium, and iron between PCOS and non-PCOS patients. PCOS patients with acne had higher magnesium levels than those without acne (P = 0.020), and PCOS patients with hirsutism had lower magnesium levels than those without hirsutism (P = 0.037). High serum copper and low calcium levels may be correlated with PCOS. Magnesium concentrations are correlated with acne and hirsutism in PCOS patients. These results provide clues to explore the mechanism of PCOS and guidance for element treatments in PCOS patients.

Association of serum organochlorine pesticides concentrations with reproductive hormone levels and polycystic ovary syndrome in a Chinese population

To investigate the serum concentrations of organochlorine pesticides (OCPs) in patients with polycystic ovary syndrome (PCOS), a total of 178 women were studied. The concentrations of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in serum were determined using Gas Chromatography Mass-Mass Spectrometer. No differences with statistical significance in the mean HCH, p,p'-DDD, p,p'-DDE concentrations were observed between the patients with PCOS and the control group. Serum p,p'-DDT (P = 0.016) and o,p'-DDT (P = 0.000) levels were significantly higher in patients with PCOS compared with the control group. The results of the association between OCPs levels and hormone levels indicated that o,p'-DDT may play a role in the pathogenesis of PCOS by affecting hormones levels. Further trials should be investigated with the findings in this study to obtain new pathogenesis of PCOS.

Blood Trace Element Concentrations in Polycystic Ovary Syndrome: Systematic Review and Meta-analysis

Polycystic ovary syndrome (PCOS) is a prevalent condition in women of reproductive age. PCOS is characterized by androgen excess and chronic anovulation and associated with low-grade inflammation and metabolic comorbidities. Some trace elements have been linked to pathophysiological mechanisms of oxidative stress and inflammation in different disorders. Therefore, we conducted a systematic review and meta-analysis of the available evidence regarding trace element concentrations in PCOS. We reviewed MEDLINE and EMBASE in search of case-control, cross-sectional, and cohort studies published until September 2015. Of 183 studies identified, six were selected for systematic review. All used the Rotterdam criteria for the diagnosis of PCOS. Two studies evaluating chromium and one assessing cobalt levels did not observe differences between PCOS and controls. Another study recorded similar nickel and vanadium levels between the groups, but lower selenium concentrations in women with PCOS compared to controls. Four studies were included in the random effects model meta-analysis, for a total of 264 PCOS and 151 control women. Copper levels were found to be higher in women with PCOS than in controls [mean difference 0.12 ppm (95 % CI 0.07; 0.17 ppm); I ² = 0 %]. Manganese [mean difference 0.04 ppm (95 % CI -0.05; 0.13 ppm); I ² = 94.4 %] and zinc concentrations [mean difference 0.02 ppm (95 % CI -0.12; 0.16 ppm); I ² = 92.4 %] were similar between the groups. The present results suggest a relationship between increased copper concentration and PCOS. This systematic review and meta-analysis is registered in PROSPERO under number CRD42016034036.

Effects of Zinc Supplementation on Endocrine Outcomes in Women with Polycystic Ovary Syndrome: a Randomized, Double-Blind, Placebo-Controlled Trial

The current study was conducted to evaluate the effects of zinc supplementation on endocrine outcomes, biomarkers of inflammation, and oxidative stress in patients with polycystic ovary syndrome (PCOS). This study was a randomized double-blind, placebo-controlled trial. Forty-eight women (18-40 years) with PCOS diagnosed according to Rotterdam criteria were randomly assigned to receive either 220 mg zinc sulfate (containing 50 mg zinc) (group 1; n = 24) and/or placebo (group 2; n = 24) for 8 weeks. Hormonal profiles, biomarkers of inflammation, and oxidative stress were measured at study baseline and after 8-week intervention. After 8 weeks of intervention, alopecia (41.7 vs. 12.5%, P = 0.02) decreased compared with the placebo. Additionally, patients who received zinc supplements had significantly decreased hirsutism (modified Ferriman-Gallwey scores) (-1.71 ± 0.99 vs. -0.29 ± 0.95, P < 0.001) and plasma malondialdehyde (MDA) levels (-0.09 ± 1.31 vs. +2.34 ± 5.53 μmol/L, P = 0.04) compared with the placebo. A trend toward a significant effect of zinc intake on reducing high-sensitivity C-reactive protein (hs-CRP) levels (P = 0.06) was also observed. We did observe no significant changes of zinc supplementation on hormonal profiles, inflammatory cytokines, and other biomarkers of oxidative stress. In conclusion, using 50 mg/day elemental zinc for 8 weeks among PCOS women had beneficial effects on alopecia, hirsutism, and plasma MDA levels; however, it did not affect hormonal profiles, inflammatory cytokines, and other biomarkers of oxidative stress.