Mahsa Darbandi

Bio: Mahsa Darbandi is an academic researcher from Avicenna Research Institute. The author has contributed to research in topics: Medicine & Sperm. The author has an hindex of 7, co-authored 16 publications receiving 254 citations. Previous affiliations of Mahsa Darbandi include Academic Center for Education, Culture and Research.

Reactive oxygen species and male reproductive hormones

Abstract: Reports of the increasing incidence of male infertility paired with decreasing semen quality have triggered studies on the effects of lifestyle and environmental factors on the male reproductive potential There are numerous exogenous and endogenous factors that are able to induce excessive production of reactive oxygen species (ROS) beyond that of cellular antioxidant capacity, thus causing oxidative stress In turn, oxidative stress negatively affects male reproductive functions and may induce infertility either directly or indirectly by affecting the hypothalamus-pituitary-gonadal (HPG) axis and/or disrupting its crosstalk with other hormonal axes This review discusses the important exogenous and endogenous factors leading to the generation of ROS in different parts of the male reproductive tract It also highlights the negative impact of oxidative stress on the regulation and cross-talk between the reproductive hormones It further describes the mechanism of ROS-induced derangement of male reproductive hormonal profiles that could ultimately lead to male infertility An understanding of the disruptive effects of ROS on male reproductive hormones would encourage further investigations directed towards the prevention of ROS-mediated hormonal imbalances, which in turn could help in the management of male infertility

HYPOGLYCEMIC EFFECT OF AQUATIC EXTRACT OF STEVIA IN PANCREAS OF DIABETIC RATS: PPARγ-DEPENDENT REGULATION OR ANTIOXIDANT POTENTIAL

Abstract: Background: Traditional medicines with anti-diabetic effects are considered suitable supplements to treat diabetes. Among medicinal herbs, Stevia Rebaudiana Bertoni is famous for its sweet taste and beneficial effect in regulation of glucose. However, little is known about the exact mechanism of stevia in pancreatic tissue. Therefore, this study investigated the possible effects of stevia on pancreas in managing hyperglycemia seen in streptozotocin-induced Sprague-Dawley rats. Methods: Sprague-Dawley rats were divided into four groups including normoglycemic, diabetic and two more diabetic groups in which, one was treated with aquatic extract of stevia (400 mg/kg) and the other with pioglitazone (10 mg/kg) for the period of 28 days. After completion of the experimental duration, rats were dissected; blood samples and pancreas were further used for detecting biochemical and histopathological changes. FBS, TG, cholestrol, HDL, LDL, ALT and AST levels were measured in sera. Moreover, MDA (malondialdehyde) level, catalase activity, levels of insulin and PPARγ mRNA expression were also measured in pancreatic tissue. Results: Aquatic extract of stevia significantly reduced the FBS, triglycerides, MDA, ALT, AST levels and normalized catalase activity in treated rats compared with diabetic rats (p<0.05). In addition to this, stevia surprisingly, increased PPARγ and insulin mRNA levels in treated rats (p<0.05). Furthermore, stevia compensated for the histopathological damage in diabetic rats. Conclusion: It is concluded that stevia acts on pancreatic tissue to elevate the insulin level and exerts beneficial anti-hyperglycemic effects through the PPARγ-dependent mechanism and stevia’s antioxidant properties.

Reactive oxygen species-induced alterations in H19-Igf2 methylation patterns, seminal plasma metabolites, and semen quality

Abstract: This study was conducted in order to investigate the effects of reactive oxygen species (ROS) levels on the seminal plasma (SP) metabolite milieu and sperm dysfunction. Semen specimens of 151 normozoospermic men were analyzed for ROS by chemiluminescence and classified according to seminal ROS levels [in relative light units (RLU)/s/106 sperm]: group 1 (n = 39): low (ROS < 20), group 2 (n = 38): mild (20 ≤ ROS < 40), group 3 (n = 31): moderate (40 ≤ ROS < 60), and group 4 (n = 43): high (ROS ≥ 60). A comprehensive analysis of SP and semen parameters, including conventional semen characteristics, measurement of total antioxidant capacity (TAC), sperm DNA fragmentation index (DFI), chromatin maturation index (CMI), H19-Igf2 methylation status, and untargeted seminal metabolic profiling using nuclear magnetic resonance spectroscopy (1H-NMR), was carried out. The methylation status of H19 and Igf2 was significantly different in specimens with high ROS (P < 0.005). Metabolic fingerprinting of these SP samples showed upregulation of trimethylamine N-oxide (P < 0.001) and downregulations of tryptophan (P < 0.05) and tyrosine/tyrosol (P < 0.01). High ROS significantly reduced total sperm motility (P < 0.05), sperm concentration (P < 0.001), and seminal TAC (P < 0.001) but increased CMI and DFI (P < 0.005). ROS levels have a positive correlation with Igf2 methylation (r = 0.19, P < 0.05), DFI (r = 0.40, P < 0.001), CMI (r = 0.39, P < 0.001), and trimethylamine N-oxide (r = 0.45, P < 0.05) and a negative correlation with H19 methylation (r = − 0.20, P < 0.05), tryptophan (r = − 0.45, P < 0.05), sperm motility (r = − 0.20, P < 0.05), sperm viability (r = − 0.23, P < 0.01), and sperm concentration (r = − 0.30, P < 0.001). Results showed significant correlation between ROS levels and H19-Igf2 gene methylation as well as semen parameters. These findings are critical to identify idiopathic male infertility and its management through assisted reproduction technology (ART).

Ooplasmic transfer in human oocytes: efficacy and concerns in assisted reproduction

Abstract: Ooplasmic transfer (OT) technique or cytoplasmic transfer is an emerging technique with relative success, having a significant status in assisted reproduction. This technique had effectively paved the way to about 30 healthy births worldwide. Though OT has long been invented, proper evaluation of the efficacy and risks associated with this critical technique has not been explored properly until today. This review thereby put emphasis upon the applications, efficacy and adverse effects of OT techniques in human. Available reports published between January 1982 and August 2017 has been reviewed and the impact of OT on assisted reproduction was evaluated. The results consisted of an update on the efficacy and concerns of OT, the debate on mitochondrial heteroplasmy, apoptosis, and risk of genetic and epigenetic alteration. The application of OT technique in humans demands more clarity and further development of this technique may successfully prove its utility as an effective treatment for oocyte incompetence.

Metabolic Fingerprinting of Seminal Plasma from Non-obstructive Azoospermia Patients: Positive Versus Negative Sperm Retrieval.

Abstract: Background Non-obstructive azoospermia (NOA) occurs in approximately 10% of infertile men. Retrieval of the spermatozoa from the testicle of NOA patients is an invasive approach. Seminal plasma is an excellent source for exploring to find the biomarkers for presence of spermatozoa in testicular tissue. The present discovery phase study aimed to use metabolic fingerprinting to detect spermatogenesis from seminal plasma in NOA patients as a non-invasive method. Methods In this study, 20 men with NOA were identified based on histological analysis who had their first testicular biopsy in 2015 at Avicenna Fertility Center, Tehran, Iran. They were divided into two groups, a positive testicular sperm extraction (TESE(+)) and a negative testicular sperm extraction (TESE(-)). Seminal plasma of NOA patients was collected before they underwent testicular sperm extraction (TESE) operation. The metabolomic fingerprinting was evaluated by Raman spectrometer. Principal component analysis (PCA) and an unsupervised statistical method, was used to detect outliers and find the structure of the data. The PCA was analyzed by MATLAB software. Results Metabolic fingerprinting of seminal plasma from NOA showed that TESE (+) versus TESE(-) patients were classified by PCA. Furthermore, a possible subdivision of TESE(-) group was observed. Additionally, TESE(-) patients were in extreme oxidative imbalance compared to TESE(+) patients. Conclusion Metabolic fingerprinting of seminal plasma can be considered as a breakthrough, an easy and cheap method for prediction presence of spermatogenesis in NOA.

Oxidative stress and male infertility: current knowledge of pathophysiology and role of antioxidant therapy in disease management

Abstract: Infertility is a global health problem involving about 15% of couples. Approximately half of the infertility cases are related to male factors. The oxidative stress, which refers to an imbalance in levels of reactive oxygen species (ROS) and antioxidants, is one of the main causes of infertility in men. A small amount of ROS is necessary for the physiological function of sperm including the capacitation, hyperactivation and acrosomal reaction. However, high levels of ROS can cause infertility through not only by lipid peroxidation or DNA damage but inactivation of enzymes and oxidation of proteins in spermatozoa. Oxidative stress (OS) is mainly caused by factors associated with lifestyle. Besides, immature spermatozoa, inflammatory factors, genetic mutations and altering levels of sex hormones are other main source of ROS. Since OS occurs due to the lack of antioxidants and its side effects in semen, lifestyle changes and antioxidant regimens can be helpful therapeutic approaches to overcome this problem. The present study aimed to describe physiological ROS production, roles of genetic and epigenetic factors on the OS and male infertility with various mechanisms such as lipid peroxidation, DNA damage, and disorder of male hormone profile, inflammation, and varicocele. Finally, the roles of oral antioxidants and herbs were explained in coping with OS in male infertility.

Long non-coding RNAs towards precision medicine in gastric cancer: early diagnosis, treatment, and drug resistance

Abstract: Gastric cancer is a deadly disease and remains the third leading cause of cancer-related death worldwide. The 5-year overall survival rate of patients with early-stage localized gastric cancer is more than 60%, whereas that of patients with distant metastasis is less than 5%. Surgical resection is the best option for early-stage gastric cancer, while chemotherapy is mainly used in the middle and advanced stages of this disease, despite the frequently reported treatment failure due to chemotherapy resistance. Therefore, there is an unmet medical need for identifying new biomarkers for the early diagnosis and proper management of patients, to achieve the best response to treatment. Long non-coding RNAs (lncRNAs) in body fluids have attracted widespread attention as biomarkers for early screening, diagnosis, treatment, prognosis, and responses to drugs due to the high specificity and sensitivity. In the present review, we focus on the clinical potential of lncRNAs as biomarkers in liquid biopsies in the diagnosis and prognosis of gastric cancer. We also comprehensively discuss the roles of lncRNAs and their molecular mechanisms in gastric cancer chemoresistance as well as their potential as therapeutic targets for gastric cancer precision medicine.

Hormones and oxidative stress: an overview

Abstract: In aerobes, oxygen is essential for maintenance of life. However, incomplete reduction of oxygen leads to generation of reactive oxygen species. These oxidants oxidise biological macromolecules present in their vicinity and thereby impair cellular functions causing oxidative stress (OS). Aerobes have evolved both enzymatic and nonenzymatic antioxidant defences to protect themselves from OS. Although hormones as means of biological coordination involve in regulation of physiological activities of tissues by regulating metabolism, any change in their normal titre leads to pathophysiological states. While, hormones such as melatonin, insulin, oestrogen, progesterone display antioxidant features, thyroid hormone, corticosteroids and catecholamines elicit free radical generation and OS, and the role of testosterone in inducing OS is debateable. This review is an attempt to understand the impact of free radical generation and cross talk between the hormones modulating antioxidant defence system under various pathophysiological conditions.