فاطمه صباغ زیارانی

Stress is known to affect many reproductive variables, including gonadotropins and sex steroid levels. Stressors such as crowding can alter the normal function of the ovaries, fallopian tubes, and uterine cycles. In the this study, we investigated the effect of crowding stress on mice oocyte parameters and reproductive organs.

Mice were divided into control, low & high- density crowding stress groups, and kept under stres condition for one month. Superovulation was induced in the mice in all groups by pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). The mice were sacrificed 15 hours after hCG injection. Grade I and IV oocytes were stained with the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method after collection and evaluation. Ovarian, fallopian tubes and uterine horns tissues were evaluated after staining with hematoxylin and eosin (H&E). Data were analyzed by ANOVA. p-value ≤0.05 was considered significant.

The number of grade I and the size of grades I and IV oocytes in the high-density crowding stress group were significantly decreased compared to those in the control group. The rate of DNA fragmentation of grade I and IV oocytes in the low and high- density crowding stress groups demonstrated a significant increase compared to that in the control group. The number of monolayer primary follicles and the height of the fallopian tube epithelium significantly decreased in the high- density crowding stress group compared to those in the control group (p≤0.05).

Crowding as an environmental stress can affect DNA fragmentation by inducing irregularities in follicular and oocyte development.

Optimizing cell culture conditions to improve oocyte growth and maturation in vitro culture conditions has been the focus of many researchers today, but the quality improvement mechanism is not fully understood. Apoptosis or programmed cell death is a process to remove old and damaged cells from tissues and plays a major role in the life of follicles and immature oocytes. Most of the defective reproductive cells as well as extra cells are removed from the ovaries through apoptosis. One of the ways to reduce oxidative stress in the laboratory culture of oocyte maturation is the use of antioxidants. Statins are drugs for the treatment of high cholesterol for which antioxidant and anti-apoptotic properties have been reported. Atorvastatin in high doses has side effects for the heart and kidneys, but in low concentrations, it has antioxidant and anti-inflammatory effects for cells, and no side effects have been reported for it.In this study, we investigated the effect of low-dose atorvastatin on the rate of apoptosis in mouse oocytes. 

24 h after PMSG (Pregnant Mare Serum Gonadotropin) inhection, 200 oocytes were obtained from adult female Wistar rats at the age of 4-5 weeks, were from were divided into 2 groups of 100 including the control group (MEM:Minimum Essential Medium culture+ Growth factor) and the atorvastatin group (MEM culture medium + 2 mg/kg atorvastatin+Growth factor) and cultured in the incubator(35 oC,CO2 %). After 24 hours of oocyte culture, Matured oocytes that met the standards of a healthy mature oocyte(oocytes that were in the first meiosis and had the first and mature polar body) were isolated the amount of apoptosis in each group was checked using tunnel staining and fluorescent microscope, the data were analyzed by variance analysis.

After 24 hours of oocyte culture, the amount of apoptosis in the group receiving atorvastatin in the culture medium and the control group was investigated. The rate of apoptosis in the atorvastatin group and the control group was 24% and 22%, respectively, In the atorvastatin group, apoptosis increased by 2% compared to the control group butt the difference between the two groups was not statistically significant (p =0.11).

According to the findings of this study, atorvastatin in low doses can have a pro-apoptotic effect and cause partial induction of apoptosis in mouse oocytes in a laboratory environment. Although this study was not conducted on other doses of atorvastatin, it is suggested that the effect of other doses of this drug on the rate of apoptosis induction should be investigated in order to make an evidence-based decision regarding its administration and use.

Studies indicate that vaccination is the most effective method of preventing infection with COVID-19. The purpose of this study is to provide vaccination considerations of patients with autoimmune/autoinflammatory rheumatologic diseases, immunodeficiencies, cancer, diabetes, chronic respiratory, and cardiovascular diseases for doctors, healthcare staff, and patients..

In this review study, a search was done in scientific electronic databases such as ISI, Google scholar, Scopus, and PubMed. The most up-to-date, relevant, and   reliable articles published in 2019-2022 were used on the topic of COVID-19 vaccines and vaccination of patients with certain diseases.

Patients with autoimmune diseases should be vaccinated against COVID-19 when the disease activity is under control and there is no co-infection. Mild immunosuppression does not reduce the antibody response to vaccines. Vaccination with all types of vaccines except for live attenuated vaccines is effective for all cancer patients, with the exception of those receiving anti-B cell therapy. Moreover, vaccination of individuals with comorbidities (obesity, cardiovascular diseases, respiratory diseases, and diabetes) which increase the risk of severe COVID-19 is recommended.

The best way to deal with the SARS-CoV-2 virus is to increase vaccination coverage to induce immune responses against this virus. It is recommended that patients with immune system defects, people who take immunosuppressive drugs, and the elderly receive booster doses of the Corona vaccine.

Atorvastatin is one of the high blood cholesterol treatment drugs that recently has been shown to have antioxidant effects in the cell. The aim of this study was to investigate the effects of atorvastatin on in vitro growth and quality of immature mouse oocytes.

Oocytes of 40 NMRI mice were removed after stimulation of ovulation and placed in culture medium. The oocytes were divided into two groups of 200 including control (culture medium) and atorvastatin group (culture medium + 2 μM atorvastatin). Then oocyte qualitative parameters of Zona pellucida thickness (ZP), Perivitelline space size (PVS) and egg diameter (OD) were determined using invert microscope and image-J software.

Quantitative parameters of Zona pellucida thickness and oocyte diameter were increased in the atorvastatin group compared to the control group. In the evaluation of oocytes quality, the number of oocytes with +1 score in the atorvastatin and control groups were (70%) and (55.4%) respectively, and the difference between the two group was significant (p≤0.05). The number of polar bodies with +1 score in the atorvastatin and control groups were (36.18%) and (18.5%) respectively (p≤0.05).

The use of atorvastatin has a significant effect on the growth and final quality of immature oocytes in vitro and in the future, it could possibly be used to increase the efficiency of in vitro fertilization