Reproductive toxicity of manganese dioxide in forms of micro- and nanoparticles in male rats

Background: Manganese Dioxide (MnO2) has long been used in industry, and its application has recently been increasing in the form of nanoparticle. Objective: The present study was an attempt to assess the effects of MnO2 nanoparticles on spermatogenesis in male rats. Materials and Methods: Micro- and nanoparticles of MnO2 were injected (100 mg/kg) subcutaneously to male Wistar rats (150 ± 20 gr) once a week for a period of 4 weeks, and the vehicle group received only normal saline (each group included 8 rats). The effect of these particles on the bodyweight, number of sperms, spermatogonia, spermatocytes, diameter of seminiferous tubes, testosterone, estrogen, follicle stimulating factor, and the motility of sperms were evaluated and then compared among the control and vehicle groups as the criteria for spermatogenesis. Results: The results showed that a chronic injection of MnO2 nanoparticles caused a significant decrease in the number of sperms, spermatogonia, spermatocytes, diameter of seminiferous tubes (p < 0.001) and in the motility of sperms. However, no significant difference was observed in the weight of prostate, epididymis, left testicle, estradiol (p = 0.8) and testosterone hormone (p = 0.2). Conclusion: It seems that the high oxidative power of both particles was the main reason for the disturbances in the function of the testis. It is also concluded that these particles may have a potential reproductive toxicity in adult male rats. Further studies are thus needed to determine its mechanism of action upon spermatogenesis

Safety Assessment of Arctium lappa L. Fruit Extract in Female Wistar Rats: Acute and Repeated Oral Toxicity Studies

Background and objectives: Arctium lappa belonging to the Compositae (Asteraceae) family has been used as a medicinal and nutritional supplement in the world. The fruits, leaves and roots of the plant are well-known for their pharmaceutical effects. Toxicity of the fruit’s extract in female rats was investigated in the present study. Methods: To assess the toxicity profile of Arctium lappa fruit extract (ALFE), it was administered to rats by gavage in acute and repeated models. The animals were divided into two groups: control and test groups. In the acute toxicity model, 1000 and 5000 mg/kg ALFE were administered to the animals. Toxic symptoms, body weight, death and abnormal behaviors were observed for 14 days. In the repeated toxicity model, ALFE (300 mg/kg) was daily administered for 4 weeks. Biochemical and histopathological changes were assessed and compared with the control group. Statistical significance was determined by one-way analyses of variance, followed by the Tukey test using GraphPad Prism 6. Results: No mortality was noticed in the acute test; therefore, the oral LD50 value determined in the female rats was greater than 5000 mg/kg. In the repeated test, the animals received ALFE (300 mg/kg) and no mortality was observed. The hematology and serum chemistry parameters showed no statistically significant changes.  The histopathological studies revealed evidences of microscopic lesions in two main organs lungs and small intestine. Conclusion: The results indicated that the oral acute toxicity of ALFE in the rats was of a low order with LD50 being more than 5000 mg/kg. Moreover, they revealed slight tissue damage to several organs when sub-chronically administered at a dose of 300 mg/kg.  </strong

Safety Assessment of Menthamozaffarianii Essential Oil: Acute and Repeated Toxicity Studies

Background:Menthamozaffarianii, an endemic species from the Labiataefamily, is used in Iranian traditional medicine. This study evaluated the acute and repeated oral toxicity of the Menthamozaffarianii essential oil (MMEO) in rats and mice. Methods:To assess the toxicity profile of the MMEO, we administered the essential oil to 48 rats and mice of both sexes by gavage in acute and repeated models. In acute toxicity, the animals were administered the MMEO (2000 mg/kg) and were monitored for 14 days. In the repeated toxicity, the MMEO was administered (100 mg/kg) daily for 4 weeks. On the 28th day, all the animals were scarified and blood and tissue samples were prepared. All the clinical, biochemical, and histopathological changes were assessed and compared with those in the controls. Statistical significance was determined by one- and two-way analyses of variance, followed by the Tukey test using GraphPad Prism 6. Results: In the acute test, there was no mortality; therefore, the oral LD50 value determined in the mice and rats of both sexes was greater than 2000 mg/kg. In the repeated test, the animals received the MMEO and there was no mortality. In the biochemical analysis, there were significant increases in blood glucose, cholesterol, ALT, AST, ALP, and TSH in the female rats and also in BUN in the male rats. The histopathological studies revealed evidence of microscopic lesions in the liver, kidney, stomach, and small intestine tissues of the MMEO group. Conclusion: The results indicated that the acute toxicity of the MMEO in the mice and rats was of a low order and it revealed slight tissue damage to several organs when given subchronically at a dose of 100 mg/kg

Osteocalcin improved Spermatogenesis in Azoospermic Mouse Model

Infertility is one of the major health concerns in the world whose globally incidence rate is on the rise. Several hormones are effective in this process, such as testosterone, estrogen and Osteocalcin (OCN). The Osteocalcin has Gprc6a receptors on leydig cells, which promotes the production of testosterone when mounted on these receptors. Therefore, the aim of this study was to investigate the role of Osteocalcin on the improvement of spermatogenesis and expression of Gprc6a receptors on leydig cells in the azoospermic mouse model.Twenty-five mice (4 to 6 weeks) were randomly divided into five groups: control, sham I Group that was initially injected by busulfan solvent (DMSO) at 5 weeks old and then by Osteocalcin solvent (PBS) after 5 weeks for one month, azoospermia Group that received busulfan (40 mg/kg/ip) at 5 weeks old. Sham II Group received busulfan 40mg/kg/ipandt hen after 5 weeks received PBS and experimental group, including azoospermic mice, was administered by Osteocalcin (3ng/g/d) for one month. After the last injection, the tests were dissected and then exposed to the tissue passage. To measure morphological changes, H & E staining was performed on a number of sections to measure the diameter of the seminiferous tubule, thickness of the germinal layer, count the spermatogonial cells, spermatocyte, round spermatid, long spermatid, Sertoli, leydigandmyoid cells. Image J software was used to conduct quantitative studies. Immunohistochemical method was employed to examine the expression of the specific receptor of Osteocalcin, Gprc6α, in the Leydig cell among the groups.The H & E staining showed a significant difference in the count the spermatogonial cells, spermatocytes, round spermatids, long spermatids, the thickness of the germ layer, the seminiferous tubule diameter between the studied groups (P<0.05).There was also no significant difference in the count of Sertoli, leydig, myoid cells and seminiferous tubule diameter between the groups (P<0.05). In the immune histochemistry, no significant difference was found in the count of GpRC6α-positive leydig cells between the groups (P< 0.05).According to the current results, the OCN plays an important role in spermatogenesis, which has a positive effect on the count of spermatocytes and spermatids, and can be further explored as an appropriate therapeutic strategy proposed for the infertility.

COVID-19 vaccine side effects on menstrual disturbances among Iranian women

Background: Many studies reported of menstrual disturbances as possible side effects of COVID-19 vaccination. Our objective was to evaluate the association between vaccination and the occurrence of menstrual disturbances among Iranian women. Methods: We used to google form questionnaires to collect reports of menstrual disturbances from 455 women aged 15–55 years in Iran. We estimated the relative risk of menstrual disturbances according to vaccination in a self-controlled case-series design after vaccination. We examined the occurrence of such disorders after the first, second and third doses of vaccine. Results: Findings The prevalence of menstrual disturbance was more in latency and heavy bleeding than others disorder after vaccination, although ֮ %50 of women doesn't have any disturbance. We observed increased risks after vaccination also for other menstrual disturbances, in menopausal women too (>10%). Discussion: Menstrual disturbances were generally common regardless of vaccination. We found a significant increase in menstrual disturbances after vaccination, particularly for latency and heavier bleeding than usual, longer duration and for short interval between menstruations. Mechanisms underlying these findings may involve bleeding disturbances in general, as well as endocrine alterations of immune system stimulation and relation to hormonal secretion

Mercuric Chloride Induced Cell Death in Spinal Cord of Embryo in Rat

A B S T R A C TIntroduction: Because of more exposure to mercury compounds, the prenatal and postnatal neurotoxic effects of mercury compounds have gained more attention in last decade. The aim of this study was to investigate the effects of mercuric chloride intoxication on spinal cord development during prenatal period. Methods: 36 adult Sprague-dawley rats after observing vaginal mating plaque (zero day of gestation) were divided into six groups: three control groups that received normal saline solution and three experimental groups that injected with mercuric chloride, 2mg/kg/IP, in 8th, 9th and 10th days of gestation. Then, embryos were removed from uterus in 15th day and spinal cord of embryos was studied by histological techniques. Results: Microscopic study of spinal cord showed that cell death, mitosis division, and extracellular spaces were increased and cells accumulation were decreased in experimental groups. Diameter of ventricular zone was increased and diameter of mantle and marginal zones were decreased. Discussion: The present study showed that mercuric chloride intoxication in prenatal period can induce cell death and results in neural tube deficits in prenatal rats

The interaction between Sertoli cells and luekemia inhibitory factor on the propagation and differentiation of spermatogonial stem cells in vitro

Background: Sertoli cells play a pivotal role in creating microenvironments essential for spermatogonial stem cells (SSCs) self-renewal and commitment to differentiation. Maintenance of SSCs and or induction of in vitro spermiogenesis may provide a therapeutic strategy to treat male infertility. Objective: This study investigated the role of luekemia inhibitory factor (LIF) on the propagation of SSCs and both functions of Sertoli cells on the proliferation and differentiation of these cells. Materials and Methods: SSCs were sorted from the testes of adult male mice by magnetic activated cell sorting and thymus cell antigen 1 antibody. On the other hand, isolated Sertoli cells were enriched using lectin coated plates. SSCs were cultured on Sertoli cells for 7 days in the absence or presence of LIF. The effects of these conditions were evaluated by microscopy and expression of meiotic and post meiotic transcripts by reverse transcriptase polymerase chain reaction. Results: Our data showed that SSCs co-cultured with Sertoli cells in the presence of LIF formed colonies on top of the Sertoli cells. These colonies had alkaline phosphatesase activity and expressed SSCs specific genes. SSCs were enjoyed limited development after the mere removal of LIF, and exhibiting expression of meiotic and postmeiotic transcript and loss of SSCs specific gene expression (p< 0.05). Conclusion: Our findings represent co-culture of SSCs with Sertoli cells provides conditions that may allow efficient proliferation and differentiation of SSCs for male infertility treatment

Protective effects of human amniotic membrane derived mesenchymal stem cells (hAMSCs) secreted factors on mouse spermatogenesis and sperm chromatin condensation following unilateral testicular torsion

Testicular torsion is considered a urological disorder that requires immediate detorsion surgery. Ischemia/reperfusion (I/R) injury after testicular torsion detorsion causes of drastic impairment of spermatogenesis and infertility. Cell-free-based approaches seem to be a promising strategy to prevent I/R injury, they have more stable biological properties, and they contain paracrine factors of mesenchymal stem cells. The purpose of this study was to evaluate the protective effects of human amniotic membrane derived mesenchymal stem cells (hAMSCs) secreted factors on mouse sperm chromatin condensation and spermatogenesis improvement after I/R injury. hAMSCs were isolated and characterized by RT- PCR and flow cytometry, preparation of hAMSCs secreted factors was performed. Forty male mice were randomly divided into 4 groups: sham-operated, torsion detorsion, torsion detorsion+ intratesticular injection of DMEM/F-12, and torsion detorsion+ intratesticular injection of hAMSCs secreted factors. After one cycle of spermatogenesis, the mean number of germ cells, Sertoli, Leydig, myoid as well as tubular parameters, Johnson score, and spermatogenesis indexes were evaluated by H& E and PAS stainings. Sperm chromatin condensation and relative expression of c-kit and prm 1 genes were assessed by aniline blue staining and real-time PCR, respectively. The mean number of spermatogenic cells, Leydig, myoid, Sertoli, spermatogenesis parameters, Johnson score, as well as germinal epithelial height and diameters of seminiferous tubules decreased significantly after I/R injury. The thickness of basement membrane and percentage of sperm with excessive histone significantly increased, while the relative expression of c-kit and prm 1 significantly decreased in torsion detorsion group (p 0.001). hAMSCs secreted factors remarkably restored normal sperm chromatin condensation, spermatogenesis parameters and histomorphometric organization of seminiferous tubules via intratesticular injection (p 0.001). Thus, hAMSCs secreted factors may potentially salvage torsion-detorsion-induced infertility

Prenatal Mercuric Chloride Exposure Causes Developmental Deficits in Rat Cortex

Introduction: Environmental pollution with heavy metals such as mercury is a major health problem. Growing studies on the field have shown the deleterious effects of mercury on human and nonhuman nervous system, especially in infants, however the effects of prenatal exposure to mercuricchloride on cortical development are not yet well understood. The aim of this study was to investigate the effect of prenatal exposure to mercuric chloride on morphological characteristics of brain cortex. Methods: Mercuric chloride (2 mg/kg) or normal saline were injected (I.P.) to 36 Sprague – dawley rats in the 8th, 9th or 10th day of gestation. The embryos were surgically removed in the 15th day of gestation, and brain cortices were studied by histological techniques. Results: Histological studies showed that embryos of mercuric chloride treated rats hadcortical neuronal disarrangement withdifferent orientations of nuclei, increased diameter of cortex, increased mitosis of cells, increased cell death, decreased cellular density and increased intracellular space. Conclusion: These findings suggest some micro structural abnormalities in cortical regions after prenatal exposure to mercuric chloride. These structural abnormalities may underliesome neurologic disturbances following mercury intoxication

Prenatal Mercuric Chloride Exposure Causes Developmental Deficits in Rat Cortex

Introduction: Environmental pollution with heavy metals such as mercury is a major health problem. Growing studies on the field have shown the deleterious effects of mercury on human and nonhuman nervous system, especially in infants, however the effects of prenatal exposure to mercuricchloride on cortical development are not yet well understood. The aim of this study was to investigate the effect of prenatal exposure to mercuric chloride on morphological characteristics of brain cortex. Methods: Mercuric chloride (2 mg/kg) or normal saline were injected (I.P.) to 36 Sprague – dawley rats in the 8th, 9th or 10th day of gestation. The embryos were surgically removed in the 15th day of gestation, and brain cortices were studied by histological techniques. Results: Histological studies showed that embryos of mercuric chloride treated rats hadcortical neuronal disarrangement withdifferent orientations of nuclei, increased diameter of cortex, increased mitosis of cells, increased cell death, decreased cellular density and increased intracellular space. Conclusion: These findings suggest some micro structural abnormalities in cortical regions after prenatal exposure to mercuric chloride. These structural abnormalities may underliesome neurologic disturbances following mercury intoxication