Unraveling the harmful effect of oxidative stress on male fertility: A mechanistic insight.

Male infertility is a widely debated issue that affects males globally. There are several mechanisms involved. Oxidative stress is accepted to be the main contributing factor, with sperm quality and quantity affected by the overproduction of free radicals. Excess reactive oxygen species (ROS) cannot be controlled by the antioxidant system and, thus, potentially impact male fertility and hamper sperm quality parameters. Mitochondria are the driving force of sperm motility; irregularities in their function may lead to apoptosis, alterations to signaling pathway function, and, ultimately, compromised fertility. Moreover, it has been observed that the prevalence of inflammation may arrest sperm function and the production of cytokines triggered by the overproduction of ROS. Further, oxidative stress interacts with seminal plasma proteomes that influence male fertility. Enhanced ROS production disturbs the cellular constituents, particularly DNA, and sperms are unable to impregnate the ovum. Here, we review the latest information to better understand the relationship between oxidative stress and male infertility, the role of mitochondria, the cellular response, inflammation and fertility, and the interaction of seminal plasma proteomes with oxidative stress, as well as highlight the influence of oxidative stress on hormones; collectively, all of these factors are assumed to be important for the regulation of male infertility. This article may help improve our understanding of male infertility and the strategies to prevent it.

Association of faecal volatiles and steroids with behavioural expression during oestrous cycle of sheep (Ovis aries).

This study was investigated to determine the faecal volatiles, steroid hormones and their correlation with behavioural signs during oestrous cycle in sheep (Ovis aries). This experiment was monitored from pro-oestrous to met-oestrous phases for correlation of endocrine dependence biochemical constituents in faeces and blood to detection of oestrous biomarkers. Medroxyprogesterone acetate sponges were used for 8 days to bring uniformity of oestrus in sheep. Faeces were collected during different phases of cycle and subjected to determination of fatty acids, minerals, oestrogens and progesterone analysis. Likewise, blood samples were also obtained for enzymatic and no-enzymatic antioxidants. The results revealed that faecal progesterone and oestrogen levels significantly increased during pro-oestrous and oestrous phase, respectively (p < .05). The blood plasma enzymatic levels showed significant demarcation during the oestrous phase than other periods (p < .05). There were also reported marked variations in volatile fatty acids across different phases of the oestrous cycle. Interestingly, methyl octanoate, methyl cis-10 pentadecenoate and methyl heptadecanoate volatiles were found to be specific to oestrus period. In addition, methyl hexanoate, methyl palmitoleate and methyl cis-9 oleate were identified in met-oestrus, indicating their possible role to be an oestrous biomarker. It is concluded that the pattern of volatile compounds and faecal steroids, in association with behavioural patterns, could be measured as a non-invasive method of heat detection in sheep.

Understanding the Immune System in Fetal Protection and Maternal Infections during Pregnancy.

The fetal-maternal immune system determines the fate of pregnancy. The trophoblast cells not only give an active response against external stimuli but are also involved in secreting most of the cytokines. These cells have an essential function in fetal acceptance or fetal rejection. Other immune cells also play a pivotal role in carrying out a successful pregnancy. The disruption in this mechanism may lead to harmful effects on pregnancy. The placenta serves as an immune barrier in fetus protection against invading pathogens. Once the infections prevail, they may localize in placental and fetal tissues, and the presence of inflammation due to cytokines may have detrimental effects on pregnancy. Moreover, some pathogens are responsible for congenital fetal anomalies and affect almost all organs of the developing fetus. This review article is designed to address the bacterial and viral infections that threaten pregnancy and their possible outcomes. Moreover, training of the fetal immune system against the exposure of infections and the role of CD49a + NK cells in embryonic development will also be highlighted.

Flavonoid enriched supplementation abrogates prenatal stress and enhances goat kids performance reared in a sub-tropical environment.

The subtropical climatic conditions in the winter season characterized by low temperature may enable to induce cold stress in pregnancy and transition periods which results in the production of reactive oxygen species. However, flavonoid enriched impact on pregnancy and lactation of Beetal goats remains unclear in a subtropical cold environment. Forty-eight multiparous pregnant Beetal goats were randomly assigned into two groups, mid-pregnancy (n = 24), late pregnancy to early lactation (n = 24). Mid-pregnancy and late pregnancy were further sub-grouped into control and supplemented with an equal number of animals. Both groups of animals were offered concentrates while the supplemented group was provided additional flavonoid-rich supplementation (Loxidan) at 120 mg/kg/head during the experimental period of 45 days in each phase of pregnancy plus 33 days of kids suckling period only in late pregnancy to early lactation group. Fractional biochemical analysis of Loxidan feed revealed it contained a rich source of total flavonoids (8268 ±â€¯92.1 µg/g) with total antioxidant capacity (14.6 ±â€¯1.7 µM/g DW). Blood was collected fifteen days apart during mid-pregnancy (60 to 105 days) and late pregnancy plus early lactation (120 to 165 days) for the assessment of serum biochemical parameters. Results revealed that serum profile of total flavonoids, total antioxidant activity, total oxidant status, malondialdehyde, superoxide dismutase, catalase, ascorbic acid, carotenoids, total phenolic, total proteins, and progesterone level showed significant values as compared to the control group in both phases of pregnancy (P < 0.05). Moreover, flavonoid enriched supplementation increased the initial kid's weight and total average weight gain as compared to the control group (P < 0.05). Overall, results illustrate that supplementation increased kid's birth weight, average daily weight gain, and fetal survival. Therefore, flavonoids could be used as an antioxidant regimen to mitigate cold stress of subtropical environment on pregnancy and lactation to improve reproductive traits.