Probiotics to improve testicular function (Andrology 5:439-444, 2017) - a comment on mechanism of action and therapeutic potential of probiotics beyond reproduction

Dietary supplementation of multi-strain probiotic in male rainbow trout (Oncorhynchus mykiss) broodstock: Effects on feed efficiency, hemato-biochemical parameters, immune response, and semen quality

The present study aimed to determine the effects of dietary probiotic supplementation on feed efficiency, physiological parameters, and semen quality of male rainbow trout (Oncorhynchus mykiss) broodstock. For this purpose, a total of 48 breeders with an average initial weight of 1366.1 ± 33.8 g were divided into 4 groups and 3 replicates. Fish were fed with diets containing 0 (control), 1 × 10⁹ (P1), 2 × 10⁹ (P2), and 4 × 10⁹ (P3) CFU multi-strain probiotic kg^-1 diet for 8 weeks. According to the results, P2 treatment significantly enhanced body weight increase, specific growth rate, and protein efficiency ratio and decreased feed conversion ratio. Moreover, the highest values of red blood cells count, hemoglobin, and hematocrit values were observed in P2 treatment (P < 0.05). The lowest levels of glucose, cholesterol, and triglyceride were found in P1, P2, and P3 treatments, respectively. Also, the highest levels of total protein and albumin were obtained in P2 and P1 treatments (P < 0.05). Based on the results, plasma enzymes contents were significantly decreased in P2 and P3 treatments. In terms of immune parameters, the complement component 3, complement component 4, and immunoglobulin M levels were increased in all probiotic-fed treatments (P < 0.05). For spermatological features, the highest spermatocrit value, sperm concentration, and motility time were observed in the P2 treatment (P < 0.05). Consequently, we conclude that multi-strain probiotics can be used as functional feed additives in male rainbow trout broodstock to enhance semen quality, improve physiological responses, and better feed efficiency.

Ligilactobacillus salivarius PS11610 exerts an effect on the microbial and immunological profile of couples suffering unknown infertility

PROBLEM

Unknown or idiopathic infertility has been associated with urogenital tract dysbiosis, reducing pregnancy and delivery ratios during assisted reproductive treatments (ART). The Ligilactobacillus salivarius PS11610 strain has shown extraordinary antimicrobial activity in vitro against urogenital pathogens as well as other probiotic characteristics. Therefore, an intervention study was performed to evaluate the effect of L. salivarius PS11610 on the microbial composition of urogenital tract in infertile couples with bacterial dysbiosis.

METHOD OF STUDY

Seventeen couples undergoing ART diagnosed with unknown infertility were selected. After confirming urogenital dysbiosis, they started a 6-month treatment with L. salivarius PS11610 (1 dose/12 h for female and 1 dose/24 h for male). Vaginal, seminal, glans, uterine and plasma samples were collected for determination of the microbiome and immune profile at the beginning and the end of the treatment.

RESULTS

Supplementation with L. salivarius PS11610 significantly modified the urogenital microbiome composition in male and female samples, solving dysbiosis of 67% of the couples. Pathogens disappeared from the vaginal samples whereas Lactobacilli percentage increased after 3 and 6 months of treatment. Moreover, L. salivarius PS11610 changed the uterine microbiome that could be associated with a change of the uterine immune profile. Additionally, the probiotic intake could be associated with the observed change in the systemic immunological profile of couples. Finally, the pregnant and delivery ratio were improved.

CONCLUSIONS

Probiotic supplementation with L. salivarius PS11610 improved the male and female urogenital tract microbiome, modulating the immune system and increasing pregnancy success in couples undergoing ART.

The Use of Probiotics for Management and Improvement of Reproductive Eubiosis and Function

Reproductive tract dysbiosis, due to the action of pathogens and/or unhealthy lifestyle, has been related to many reproductive diseases and disorders in mammalian species. Classically, such a problem has been confronted by the administration of antibiotics. Despite their effectiveness for controlling disease, treatments with antibiotics may negatively affect the fertility of males and females and, mainly, may induce antibiotic resistance. Accordingly, safer alternatives for maintaining reproductive system eubiosis, such as probiotics, are required. The present review summarizes the current knowledge on the biodiversity of the microbiota at the reproductive tract, possible changes in the case of dysbiosis, and their relationships with adequate reproductive health and functioning in both females and males. Afterwards, mechanisms of action and benefits of different probiotics are weighed since the biological activities of probiotics may provide a promising alternative to antibiotics for maintaining and restoring reproductive eubiosis and function. However, at present, it is still necessary for further research to focus on: (a) identifying mechanisms by which probiotics can affect reproductive processes; (b) the safety of probiotics to the host, specifically when consumed during sensitive reproductive windows such as pregnancy; and (c) the hazards instructions and regulatory rules required for marketing these biological-based therapies with sufficient safety. Thus, in this review, to draw a comprehensive overview with a relatively low number of clinical studies in this field, we showed the findings of studies performed either on human or animal models. This review strategy may help provide concrete facts on the eligible probiotic strains, probiotics colonization and transfer route, and prophylactic and/or therapeutic effects of different probiotic strains.

Long Exposure to a Diet Supplemented with Antioxidant and Anti-Inflammatory Probiotics Improves Sperm Quality and Progeny Survival in the Zebrafish Model

The aim of the present experiment is to study the effects of oral ingestion of a mixture of two probiotic bacteria on sperm quality and progenies. Three homogeneous groups of juvenile zebrafish were created. Once having reached adulthood (3 months postfertilization; mpf), each group received different feeding regimens: a standard diet (control), a maltodextrin-supplemented diet (vehicle control), or a probiotic-supplemented diet (a mixture (1:1) of Lactobacillus rhamnosus CECT8361 and Bifidobacterium longum CECT7347). The feeding regime lasted 4.5 months. Growth parameters (weight and length) were determined at 3, 5, and 7.5 mpf. Sperm motility was evaluated using computer-assisted sperm analysis at 5 and 7.5 mpf. Progeny survival, hatching rate, and malformation rate were also evaluated. Results showed that probiotic-supplemented diet improved growth parameters compared with the standard diet. The highest percentage of motile spermatozoa was reported in the probiotic-fed group. Concomitantly, the percentage of fast sperm subpopulation was significantly lower in samples derived from control males. Furthermore, there was a significant difference in progeny survival between the probiotic-fed group and the control group at three developmental times (24 hours postfertilization (hpf), 5 days postfertilization (dpf) and 7 dpf). In conclusion, in zebrafish, prolonged ingestion of a mixture of Lactobacillus rhamnosus CECT8361 and Bifidobacterium longum CECT7347 has positive effects on growth, sperm quality, and progeny survival.

Obesity related metabolic endotoxemia is associated with oxidative stress and impaired sperm DNA integrity

Background

Obesity is known to be associated with inflammation, oxidative stress and a resulting reduction in sperm DNA integrity. Importantly, obesity is also reported to be associated with an increase in intestinal permeability with the passage of intestinal bacteria into the circulation (metabolic endotoxemia) that triggers a systemic state of inflammation and resultant oxidative stress. Therefore, we hypothesised that this obesity related increase in intestinal permeability and resultant metabolic endotoxemia (ME) may activate inflammation within the male reproductive tract, leading to increased reactive oxygen species production, sperm oxidative stress and a decline in DNA integrity.

Results

Our pilot study of 37 infertile men confirmed a significant positive correlation between body mass index (BMI), increased intestinal permeability (serum zonulin), metabolic endotoxaemia (LBP), sperm DNA oxidative damage (seminal 8 OhDG) and increasing levels of sperm DNA fragmentation (Halosperm). Metabolic endotoxemia was positively correlated with increasing levels of sperm DNA oxidative damage with this relationship remaining significant, even after adjustment for relevant confounders such as age, BMI and days of abstinence. These observations suggest that metabolic endotoxemia and its associated oxidative stress may be a key driver of sperm DNA damage in obese men.

Conclusion

This study confirms a link between obesity, increasing intestinal permeability and endotoxin exposure, and oxidative mediated sperm DNA damage. This warrants further investigation to fully understand the effect of metabolic endotoxemia on male reproductive function which could result in the new therapies to improve male fertility potential.

Diet Supplemented with Antioxidant and Anti-Inflammatory Probiotics Improves Sperm Quality after Only One Spermatogenic Cycle in Zebrafish Model

Infertility is a medical concern worldwide and could also have economic consequences in farmed animals. Developing an efficient diet supplement with immediate effects on sperm quality is a promising tool for human reproduction and for domesticated animal species. This study aims at elucidating the effect of a short-time probiotic supplementation consisting of a mixture of two probiotic bacteria with proven antioxidant and anti-inflammatory activities on zebrafish sperm quality and male behavior. For this purpose, three homogeneous groups of males in terms of motility (<60%) were established. The control group was fed with a normal standard diet. The other received supplements: One group (vehicle control) was fed with maltodextrin and the other received a probiotic preparation based on a mixture (1:1) of Lactobacillus rhamnosus CECT8361 and Bifidobacterium longum CECT7347. The feeding regime was 21 days corresponding with a single spermatogenesis in zebrafish. The preparation did not modify animal weight, positively affected the number of fluent males, increased sperm concentration, total motility, progressive motility, and fast spermatozoa subpopulations. Moreover, the animals fed with the supplement showed different behavior patterns compared to control groups. Our results suggest a diet-related modulation on the exploration activity indicating a lower stress-like conduct. The studied formulation described here should be considered as advantageous in male reproductive biotechnology.