Effects of betaine and ascorbic acid supplementation on serum gonadotropin, testicular histological analysis and sperm quality in male Japanese quails during the dry season

Mechanisms underlying reproductive responses of Japanese quails to heat stress conditions

Exposure to heat stress can cause a significant increase in the death rate and disease susceptibility of poultry birds, ultimately impacting the profitability of the poultry industry. Despite being a more economical choice, Japanese quails (Coturnix japonica) are not immune to the harmful effects of heat stress. Quails may experience negative effects on their reproductive performance due to excessive reactive molecules caused by heat stress. However, they have developed various mechanisms to maintain their reproductive abilities in such conditions. The neuroendocrine system in birds plays a vital role in regulating their reproductive responses to thermal stress, and it is also connected to other environmental factors such as photoperiod that can impact their reproductive performance. Hormones are crucial in the complex interactions necessary for sexual maturation and reproductive responses to heat stress in Japanese quails living in stressful thermal conditions.

Betaine alleviates spermatogenic cells apoptosis of oligoasthenozoospermia rat model by up-regulating methyltransferases and affecting DNA methylation

BACKGROUND

Oligoasthenozoospermia is the most common type of semen abnormality in male infertile patients. Betaine (BET) has been proved to have pharmacological effects on improving semen quality. BET also belongs to endogenous physiological active substances in the testis. However, the physiological function of BET in rat testis and its pharmacological mechanism against oligoasthenozoospermia remain unclear.

PURPOSE

This research aims to prove the therapeutic effect and potential mechanism of BET on oligoasthenozoospermia rat model induced by Tripterygium wilfordii glycosides (TWGs).

METHODS

The oligoasthenozoospermia rat model was established by a continuous gavage of TWGs (60 mg/kg) for 28 days. Negative control group, oligoasthenozoospermia group, positive drug group (levocarnitine, 300 mg/kg), and 200 mg/kg, 400 mg/kg, and 800 mg/kg BET groups were created for exploring the therapeutic effect of BET on the oligoasthenozoospermia rat model. The therapeutic effect was evaluated by HE and TUNEL staining. Immunofluorescence assay of DNMT3A, PIWIL1, PRMT5, SETDB1, BHMT2, and METTL3, methylation capture sequencing, Pi-RNA sequencing, and molecular docking were used to elucidate potential pharmacological mechanisms.

RESULTS

It is proved that BET can significantly restore testicular pathological damage induced by TWGs, which also can significantly reverse the apoptosis of spermatogenic cells. The spermatogenic cell protein expression levels of DNMT3A, PIWIL1, PRMT5, SETDB1, BHMT2, and METTL3 significantly decreased in oligoasthenozoospermia group. 400 mg/kg and 800 mg/kg BET groups can significantly increase expression level of the above-mentioned proteins. Methylation capture sequencing showed that BET can significantly increase the 5mC methylation level of Spata, Spag, and Specc spermatogenesis-related genes. Pi-RNA sequencing proved that the above-mentioned genes produce a large number of Pi-RNA under BET intervention. Pi-RNA can form complexes with PIWI proteins to participate in DNA methylation of target genes. Molecular docking indicated that BET may not directly act as substrate for methyltransferase and instead participates in DNA methylation by promoting the methionine cycle and increasing S-adenosylmethionine synthesis.

CONCLUSION

BET has a significant therapeutic effect on oligoasthenozoospermia rat model induced by TWPs. The mechanism mainly involves that BET can increase the methylation level of Spata, Specc, and Spag target genes through the PIWI/Pi-RNA pathway and up-regulation of methyltransferases (including DNA methyltransferases and histone methyltransferases).

Effect of ascorbic acid on metabolic status, lipid peroxidation, antioxidant activity and quality of frozen Indian red jungle fowl (Gallus gallus murghi) semen

The Indian red jungle fowl population is decreasing in its natural habitat. Its conservation through semen cryopreservation with sufficient live sperm recovery rate is requisite where ascorbic acid could play significant role to mitigate cryo-incited injuries. The objective was to elucidate the effect of ascorbic acid on freezability of Indian red jungle fowl sperm. Pooled semen was aliquoted and diluted (1:5) with red fowl extender having ascorbic acid: 0.0 (control), 1.0, 2.0 and 4.0 mM. Diluted samples were cryopreserved and semen quality was assessed at post-dilution, cooling, equilibration and freeze-thawing stages. Sperm metabolic status, antioxidant potential and lipid peroxidation were studied at post-dilution and freeze-thawing. Sperm motility did not differ (p > .05) in experimental extenders and control at post-dilution and cooling; however, it was recorded higher (p < .05) with ascorbic acid at 2.0 mM compared with other levels at post-equilibration and post-thawing stage. Sperm viability, plasma membrane and acrosome intactness were recorded higher (p < .05) with 2.0 mM ascorbic acid compared with other concentrations of ascorbic acid at all stages of cryopreservation. Sperm metabolic status and antioxidant potential were recorded higher (p < .05), while lipid peroxidation was recorded lowest (p < .05) with 2.0 mM ascorbic acid compared with 1.0, 4.0 mM and control. In conclusion, ascorbic acid at 2.0 mM in red fowl extender improves quality, metabolic status and antioxidant potential of frozen Indian red jungle fowl semen through ameliorating lipid peroxidation.

Efficacy of soursop juice extender on rooster semen quality, oxidative activity and spermatozoa kinematics

African medicinal plant like soursop (Annona muricate L.) within annonaceae are known for their biological, therapeutic, and pharmacological properties with little or no toxicity. The use of such plant requires good knowledge of the toxicity dosage, purity, suitable extraction solvent and adverse effects. The leaves, seeds, fruits, barks, and roots of African medicinal plants have been used for various nutraceuticals and functional effects according to African folk medicine. The aim of this study is to evaluate the semen quality, oxidative activity and spermatozoa kinematics of rooster semen in soursop juice extender. About 30 roosters were used for the in vitro analysis. Semen was collected twice a week for 2 weeks through dorsal-abdominal massage technique. The evaluation was done hourly until semen quality declined at the 5th-hour. The pooled semen was allotted to seven treatments of semen extenders as undiluted semen, dextrose saline, 10% soursop juice extender, 20% soursop juice extender, 30% soursop juice extender, 40% soursop juice extender, and 50% soursop juice extender for the study. The percentage motility, progressive motility, nonprogressive motility, curvilinear velocity, average path velocity, straight line velocity, linearity, straightness, amplitude of lateral head, beat cross frequency and wobble were analyzed using computer aided sperm analysis. Oxidative status (antioxidant activity and lipid peroxidation) was determined by assay. Result of rooster semen at room temperature and after 1-hour dilution showed that percentage motility, nonprogressive motility, and average path velocity were significantly (P < 0.05) reduced by different soursop juice extenders compared to undiluted semen. After 2-hour dilution of rooster semen, nonprogressive motility, average path velocity, curvilinear velocity, straight line velocity, wobble, liveability and amplitude of lateral head parameters were significantly (P < 0.05) increased by different soursop juice extenders compared to undiluted semen. Antioxidant activity and lipid peroxidation in both room temperature and after 5-hour dilution were affected by different soursop juice extenders in rooster semen. In conclusion, supplementation of soursop juices as an extender to rooster undiluted semen played an improvement role on spermatozoa fertility and oxidative status during processing or preserving ejaculates for insemination.

Functional roles of taurine, L-theanine, L-citrulline, and betaine during heat stress in poultry

Heat stress (HS) is an important environmental stress factor affecting poultry production on a global scale. With the rise in ambient temperature and increasing effects of global warming, it becomes pertinent to understand the effects of HS on poultry production and the strategies that can be adopted to mitigate its detrimental impacts on the performance, health, welfare, immunity, and survival of birds. Amino acids (AAs) have been increasingly adopted as nutritional modifiers in animals to ameliorate the adverse effects of HS. They are essential for protein synthesis, growth, maintenance, reproduction, immunity, stress response, and whole-body homeostasis. However, HS tends to adversely affect the availability, transport, absorption, and utilization of these AAs. Studies have investigated the provision of these AAs to poultry during HS conditions, and variable findings have been reported. Taurine, L-theanine, and L-citrulline are non-essential amino acids that are increasingly gaining attention as nutritional supplements in HS animals. Similarly, betaine is an amino acid derivative that possesses favorable biological properties which contributes to its role as a functional additive during HS. Of particular note, taurine is negligible in plants, while betaine, L-theanine, and L-citrulline can be found in selected plants. These nutrients are barely found in feed ingredients, but their supply has been shown to elicit important physiological roles including anti-stress effects, anti-oxidative, anti-inflammatory, gut promoting, and immunomodulatory functions. The present review provides information on the use of these nutritionally and physiologically beneficial nutrients as functional additives to poultry diets during HS conditions. Presently, although several studies have reported on the positive effects of these additives in human and murine studies, however, there is limited information regarding their utilization during heat stress in poultry nutrition. Therefore, this review aims to expound on the functional properties of these nutrients, their potentials for HS alleviation, and to stimulate further researches on their biological roles in poultry nutrition.

Dietary ascorbic acid and betaine improve stress responses, testosterone levels and some sexual traits in male Japanese quails during the dry season

The experiment investigated the effects of dietary ascorbic acid and betaine stress responses, serum testosterone levels, and some sexual traits in male Japanese quails during the dry season. A total of 240 male Japanese quails (14 days old) were used and randomly assigned to four groups, each group has three replicates (n = 20). Birds in treatment groups were fed ascorbic acid (AA); betaine (BET); and AA + BET in their diets, whereas the control birds were fed only basal diet. Environmental conditions were predominantly outside thermoneutral zone for Japanese quails. Dietary AA ± BET increased (p < .05) serum catalase, reduced glutathione and testosterone, but lowered (p < .05) cortisol levels when compared with control group. Supplemental AA, BET, or AA + BET enhanced (p < .05) cloacal gland size and sexual traits. In conclusion, dietary AA and BET improved stress responses, serum testosterone levels, and some sexual traits in male Japanese quails during the dry season.