Nitric oxide synthase and its function in animal reproduction: an update

Nitric oxide (NO), a free radical labile gas, is involved in the regulation of various biological functions and physiological processes during animal reproduction. Recently, increasing evidence suggests that the biological role and chemical fate of NO is dependent on dynamic regulation of its biosynthetic enzyme, three distinct nitric oxide synthase (NOS) according to their structure, location and function. The impact of NOS isoforms on reproductive functions need to be timely elucidated. Here, we focus on and the basic background and latest studies on the development, structure, importance inhibitor, location pattern, complex functions. Moreover, we summarize the exactly mechanisms which involved some cell signal pathways in the regulation of NOS with cellular and molecular level in the animal reproduction. Therefore, this growing research area provides the new insight into the important role of NOS male and female reproduction system. It also provides the treatment evidence on targeting NOS of reproductive regulation and diseases.

Endocrine disrupting micropollutants in water and their effects on human fertility and fecundity

INTRODUCTION AND OBJECTIVE

Micropollutants (MPs) are defined as persistent and biologically-active substances which occur in the environment in trace amounts, mainly as a result of industrial processes and human domestic activity. The published experimental data prove that, among other things, MPs present in the environment may also affect and disturb hormonal balance in humans, resulting in impairment of the reproductive function. In addition to the many MPs disrupting endocrine function described in literature and which exert an effect on human reproductive function, the study presents a review of current literature concerning the exposure to Bisphenol A, phthalates, organochlorine pesticides, and pyrethroids.

REVIEW METHODS

Two independent authors searched in PubMed and Google scholar (any date until September 2022) for studies concerning chosen endocrine-disrupting MPs in water and their effects on human fertility and fecundity.

BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE

The review of the literature showed that EDMs present in the environment may create risk in the prenatal and postnatal development following premature birth, and exert a negative effect on fertility and reproductive functions in humans, especially during the perinatal period.

SUMMARY

The presented review of literature indicates a negative effect of exposure to BPA, phthalates, OC and OP pesticides, as well as to pyrethroids, regarding human reproductive health. It also demonstrated considerable differences according to gender. Generally, there is a definitely stronger evidence for the presence of a cause-effect relationship between the discussed EDMs and a decreased fertility and fecundity in males. The negative effect of exposure to Bisphenol A, phthalates, selected organochlorine pesticides and pyrethroids appears to be quite well documented.

Microbiota of female genital tract - functional overview of microbial flora from vagina to uterine tubes and placenta

Microorganisms and eukaryotic human cells coexist in synergistic relationships in nearly every niche of the human body. The female genital tract consisting of the vagina, uterus with its cervix and endometrium, uterine tubes and ovaries - harbors its own typical microbiota, which accounts for 9 % of the total bacterial population in females. To this organ system, we also assigned the microbiome of the placenta, which has not been studied much until now. Among the spectrum of microbial species, the female genital tract is mainly dominated by Lactobacillus species, which are considered to be one of the simplest yet most important microbial communities. However, this relationship between macro- and micro-organisms seems to have a number of physiological functions, e.g., the vaginal and cervical microbiota have unique impact on reproductive health. The aim of this review was to provide current view on female genital tract microbiota and its role in reproductive health. We describe in detail the association of vaginal or tubal epithelium with microbiota or the role of microbiota in normal placental function.

[The effect of sex hormones and pregnancy on development and progression of uveal melanoma]

The analysis of literature revealed that men experience uveal melanoma (UM) more frequently and with worse prognosis. There are also descriptions of an aggressive course of UM in pregnant women. These facts prompted researchers to analyze the effect of sex hormones and pregnancy on the development and progression of UM. Many years of international experience have refuted the presence of a reliable difference between 5-year survival and 5-year survival without metastases between non-pregnant women with UM and pregnant women with UM. That data is regarded as level 3 evidence. The experts have concluded that UM is not a contraindication to current or future pregnancy, and exogenous hormones (oral contraceptives or hormone replacement therapy) do not affect the incidence and prognosis of UM. Publications provide evidence of expression of the receptors of certain sex hormones (ER, ERRα, LH and LHRH) in primary UM, as well as overexpression of the ESR1 and ESR2 genes in UM with poor predictive characteristics. Overall AR mRNA expression in UM was low, but it was higher in epithelial UMs. The fact of expression of estrogen receptors in UM gives grounds to experiment with them as a target for therapy.

Lipid Metabolism and Relevant Disorders to Female Reproductive Health

BACKGROUND

Lipids are essential components of cells that participate in metabolic and endocrine regulation and reproductive functions. The main organs where lipid regulation takes place are the liver and adipose tissue. Besides, when each tissue specific action cannot be exerted, it could lead to several endocrine-metabolic disorders closely related to PCOS, such as non-alcoholic fatty liver disease (NAFLD) and obesity.

OBJECTIVE

This work aims to discuss the impact of lipid alterations on metabolic and reproductive health. Therefore, this review focus on the importance of carrying out an integrated study of the molecular pathways affected in PCOS for developing target therapies.

RESULTS

Lipids play a major role in PCOS pathogenesis. In this regard, failures in lipid regulation, synthesis, and/or homeostasis contribute to metabolic and reproductive abnormalities, such as those seen in PCOS. Several lipid pathways and regulators are altered in this pathology, leading to dysfunctions that worsen reproductive functions. Therefore, there are several treatments to manage dyslipidemias. Non-pharmacological therapies are considered a first line treatment being the pharmacological treatments a second line option.

CONCLUSION

The best treatment to improve the lipid profile is a lifestyle intervention, a combination of hypocaloric diet and exercise. Regarding pharmacological therapies, a combination of fibrate and statins would be the most recommended drugs. Still, in PCOS women, treatment with metformin or TZDs not only modulates the lipid metabolism, but also improves the ovulation. Also, metformin with lifestyle interventions has positive effects on the metabolic and reproductive features of PCOS patients.

A pilot study on the effect of early provision of dietary docosahexaenoic acid on testis development, functions, and sperm quality in rats exposed to prenatal ethanol

BACKGROUND

Prenatal ethanol (EtOH) exposure is associated with adverse effect on the male reproductive function. Dietary docosahexaenoic acid (DHA) is known to improve testis function and sperm parameters, thereby male fertility. This study piloted whether dietary DHA influences testis development and function in rats exposed to prenatal EtOH.

METHODS

Pregnant female Sprague-Dawley rats (n = 30) received either EtOH (3 g/kg, twice a day, n = 14) or dextrose (n = 16) throughout pregnancy. Moreover, they were fed either diet supplemented with (Cont + DHA, n = 8, EtOH + DHA, n = 6) or without DHA (1.4% w/w of total fatty acids) (Cont, EtOH, n = 8 each), with pups being continued on their mothers' diet after weaning. Tissues were collected at gestational day (GD) 20, postnatal day (PD) 4, 21, 49 and 90 for analyzing testicular developmental markers and sperm parameters, and plasma for testosterone.

RESULTS

Dietary DHA increased serum testosterone at GD20 (p < .05) and sperm normal morphology at PD90 (p < .0001) compared to the group without DHA supplementation. Dietary DHA also increased the height of germinal epithelium at peripuberty, PD49 (p < .03). The EtOH exposure induced a marked decline in the testicular gene expression of StAR at PD49 (p < .02) than those of non-EtOH treated group.

CONCLUSIONS

These findings indicate that dietary DHA may positively contribute to male fertility by impacting sperm normal morphology likely by increasing fetal testosterone level. Prenatal EtOH exposure did not adversely affect the overall testis developmental markers during development and sperm parameters in adulthood.

Breast Cancer in Turkey; An Analysis of 20.000 Patients with Breast Cancer

Objective

Breast cancer is the most common type of cancer and the leading cause of cancer-related deaths in women in Turkey. This study presents the characteristics of patients registered in National Breast Cancer Registry Program of Turkish Federation of Breast Diseases Societies.

Materials and Methods

The registry contains 242 variables under 10 categories and 699 questions. Patients were recorded (online and offline) from nationwide breast centers around Turkey.

Results

Twenty-thousand patients were registered between May 2005 and April 2017 at 36 centers. After data cleaning, 19,503 women were included in the study. The median age at diagnosis was 51 [14-97]; 17.2% were younger than 40 and 37.2% were premenopausal; 13.6% were nulliparous. Breast conserving surgery rate was 39.3%. Histopathology was invasive ductal cancer in 77%. Majority of patients had stage II cancer (48.3%). Estrogen, progesterone and HER-2 receptor positivity rates in invasive breast cancer were 72.5%, 62.5% and 21.8%, respectively. The mean tumor diameter was 2.5±1.7 cm. During the mean 51.6 months of follow-up, the local/regional and systemic recurrence rates were 3.7% and 5.2%, respectively; five and 10-year overall survival rates were 86% and 76%.

Conclusion

Despite increasing number of screening centers and free-of-charge mammography (ages 40 to 69) and mobile screening systems in recent years, a significant portion of patients were diagnosed at advanced stage due to lack of breast cancer awareness. In contrast with the study published 5 years ago, there was a decrease in the rate of pre-menopausal women and an increase in the breast conserving surgery.

Effects of apelin on reproductive functions: relationship with feeding behavior and energy metabolism

Apelin is an adipose tissue derived peptidergic hormone. In this study, 40 male Sprague-Dawley rats were used (four groups; n = 10). Apelin-13 at three different dosages (1, 5 and 50 μg/kg) was given intraperitoneally while the control group received vehicle the same route for a period of 14 days. In results, apelin-13 caused significant decreases in serum testosterone, luteinizing hormone and follicle-stimulating hormone levels (p < 0.05). Administration of apelin-13 significantly increased body weights, food intake, serum low-density lipoprotein and total cholesterol levels (p < 0.05), but caused significant decreases in high-density lipoprotein levels (p < 0.05). Serum glucose and triglyceride levels were not significantly altered by apelin-13 administration. Significant decreases in both uncoupling protein (UCP)-1 levels in the white and brown adipose tissues and UCP-3 levels in the biceps muscle (p < 0.05) were noted. The findings of the study suggest that apelin-13 may not only lead to obesity by increasing body weight but also cause infertility by suppressing reproductive hormones.