Effect of glutamine supplementation and replacement of tris-egg yolk based extender with defatted cow milk on spermatozoa quality after equilibration and thawing

Taxifolin increased semen quality of Duroc boars by improving gut microbes and blood metabolites

Taxifolin (TAX), as a natural flavonoid, has been widely focused on due to its strong anti-oxidation, anti-inflammation, anti-virus, and even anti-tumor activity. However, the effect of TAX on semen quality was unknown. The purpose of this study was to analyze the beneficial influences of adding feed additive TAX to boar semen in terms of its quality and potential mechanisms. We discovered that TAX increased sperm motility significantly in Duroc boars by the elevation of the protein levels such as ZAG, PKA, CatSper, and p-ERK for sperm quality. TAX increased the blood concentration of testosterone derivatives, antioxidants such as melatonin and betaine, unsaturated fatty acids such as DHA, and beneficial amino acids such as proline. Conversely, TAX decreased 10 different kinds of bile acids in the plasma. Moreover, TAX increased “beneficial” microbes such as Intestinimonas, Coprococcus, Butyrivibrio, and Clostridium_XlVa at the Genus level. However, TAX reduced the “harmful” intestinal bacteria such as Prevotella, Howardella, Mogibacterium, and Enterococcus. There was a very close correlation between fecal microbes, plasma metabolites, and semen parameters by the spearman correlation analysis. Therefore, the data suggest that TAX increases the semen quality of Duroc boars by benefiting the gut microbes and blood metabolites. It is supposed that TAX could be used as a kind of feed additive to increase the semen quality of boars to enhance production performance.

The effect of L-glutamine and trehalose on dog sperm cryopreservation

This study aimed to test different doses of L-glutamine and trehalose in the canine semen diluent while determining their protective effects on spermatological and biochemical indices of the thawed samples. Semen samples were collected from three fertile dogs using the digital manipulation method. The mixed ejaculates were divided into five portions at 37 °C and diluted with additives. Five study groups were formed with L-glutamine (10 and 20 mM), trehalose (25 and 50 mM), and no additives (control). After the dilution, the semen samples were cooled for 1.5 h at 5 °C and frozen (-110 to -120 °C) in liquid nitrogen vapor. Then, they were stored at -196 °C. For spermatological evaluations, samples were thawed at 38 °C for 30 s. L-glutamine (20 mM) was found to be significantly different (P < 0.05) and led to higher percentages of motility, membrane integrity, and acrosome integrity compared to the control group. Considering the total oxidant status (TOS) assay, the lower values were determined in all the antioxidant groups compared to the control group (P < 0.05). Supplementing the semen extender with L-glutamine showed a higher total antioxidant status (TAS) concentration compared to the control group (P < 0.05). As a result of this study, a higher protective effect was found in all the spermatological evaluations after thawing the frozen semen samples, especially in the group containing L-glutamine (20 mM).

DNA damaging effect of paclitaxel in the epididymal sperms as a chemotherapeutic agent and possible remedies to prevent this effect: A study on reproductive potential of male cancer patients of reproductive age

Cancer is a major public health problem, young cancer patients therefore undergo chemotherapy, and most of them may lose their fertility. DNA damage level provides important clues about the quality and reproductive potential of spermatozoa. In this study, we evaluated the levels of both DNA fragmentation and abnormal DNA integrity in the epididymal sperms of New Zealand rabbit (Oryctolagus cuniculus) after cryopreservation using the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assay and the toluidine blue (TB) staining methods and assessed the effects of paclitaxel, resveratrol, l-glutamine (LG), and basal medium eagle (BME) solution on DNA damage. Paclitaxel induced the levels of both DNA damages in the sperms, but resveratrol ameliorated this effect. LG and BME supplementation to the extender prevented the sperm samples from DNA fragmentation after cryopreservation. Chemotherapy drugs containing paclitaxel can cause the sperm DNA to be damaged, and hence adversely affect the fertility of male cancer patients of reproductive age. The administration of resveratrol together with paclitaxel may ameliorate the DNA damage inducing effect of paclitaxel. Sperm banking and cryopreservation with the appropriate cryoprotectants such as LG and BME prior to cancer treatment can also be suggested to all male cancer patients of reproductive age facing cancer treatment for fertility preservation.