AFM1 exposure in male balb/c mice and intervention strategies against its immuno-physiological toxicity using clay mineral and lactic acid bacteria alone or in combination

CONTEXT

Aflatoxins are the most harmful mycotoxins that cause human and animal health concerns. Aflatoxin M1 (AFM1) is the primary hydroxylated metabolite of aflatoxin B1 and is linked to the development of hepatocellular carcinoma and immunotoxicity in humans and animals. Because of the important role of dairy products in human life, especially children, AFM1 is such a major concern to humans because of its frequent occurrence in dairy products at concentrations high enough to cause adverse effects to human and animal health. Reduced its bioavailability becomes a high priority in order to protect human and animal health.

OBJECTIVES

This study aimed to investigate, in vivo, the ability of lactic acid bacteria (lactobacillus rhamnosus GAF01, LR) and clay mineral (bentonite, BT) mixture to mitigate/reduce AFM1-induced immunotoxicity, hepatotoxicity, nephrotoxicity and oxidative stress in exposed Balb/c mice.

MATERIALS AND METHODS

The in vivo study was conducted using male Balb/c mice that treated, orally, by AFM1 alone or in combination with LR and/or BT, daily for 10 days as follows: group 1 control received 200 µl of PBS, group 2 treated with LR alone (2.108 CFU/mL), group 3 treated with BT alone (1 g/kg bw), group 4 treated with AFM1 alone (100 μg/kg), group 5 co-treated with LR + AFM1, group 6 co-treated with BT + AFM1, group 7 co-treated with BT + LR + AFM1. Forty-eight h after the end of the treatment, the mice were sacrificed and the blood, spleen, thymus, liver and kidney were collected. The blood was used for biochemical and immunological study. Spleen and thymus samples were used to thymocytes and splenocytes assessments. Liver and kidney samples were the target for evaluation of oxidative stress enzymes status and for histological assays.

RESULTS

The results showed that AFM1 caused toxicities in male Blab/c mice at different levels. Treatment with AFM1 resulted in severe stress of liver and kidney organs indicated by a significant change in the biochemical and immunological parameters, histopathology as well as a disorder in the profile of oxidative stress enzymes levels. Also, it was demonstrated that AFM1 caused toxicities in thymus and spleen organs. The co-treatment with LR and/or BT significantly improved the hepatic and renal tissues, regulated antioxidant enzyme activities, spleen and thymus viability and biochemical and immunological parameters. LR and BT alone showed to be safe during the treatment.

CONCLUSION

In summary, the LR and/or BT was able to reduce the biochemical, histopathological and immunological damages induced by AFM1 and indeed it could be exploited as one of the biological strategies for food and feedstuffs detoxification.

The ameliorative effect of Lactobacillus paracasei BEJ01 against FB1 induced spermatogenesis disturbance, testicular oxidative stress and histopathological damage

Fumonisin B1 (FB1) is a possible carcinogenic molecule for humans as classified by the International Agency for Research on Cancer (IARC) in 2B group. In livestock, it is responsible for several mycotoxicoses and economic losses. Lactobacillus strains, inhabitants of a wide range of foodstuffs and the gastrointestinal tract, are generally recognized as safe (GRAS). Thus, the aim of this work was to evaluate the protective effect of Lactobacillus paracasei (LP) against FB1-induced reprotoxicities including testicular histopathology, sperm quality disturbance, and testosterone level reduction.Pubescent mice were divided randomly into four groups and treated for 10 days. Group 1: Control; Group 2: FB1 (100 μg/kg b.w); Group 3: LP (2 × 109 CFU/kg b.w); Group 4: LP (2 × 109 CFU/kg b.w) and FB1 (100 μg/kg b.w). After the end of the treatment, animals were sacrificed. Plasma, epididymis, and testis were collected for reproductive system studies.Our results showed that FB1 altered epididymal sperm quality, generated oxidative stress, and induced histological alterations. Interestingly, these deleterious effects have been counteracted by the LP administration in mice.In conclusion, LP was able to prevent FB1-reproductive system damage in BALB/c mice and could be validated as an anti-caking agent in an animal FB1-contaminated diet.

Potential protective effect of lactic acid bacteria against zearalenone causing reprotoxicity in male mice

Zearalenone (ZEN) is a worldwide fusarotoxin that poses a threat to the consumer due to its chronic toxicity. Herein we examined the effects of ZEN on adult mouse testis, focusing on oxidative stress, biochemical and morphological parameters. In addition, since cytoskeletal remodeling is a key event for the production of good quality gametes, the expression and localization of two proteins, Dishevelled-associated activator of morphogenesis 1 (DAAM1) and Prolyl endopeptidase (PREP), involved in cytoskeletal dynamics during spermatogenesis were evaluated. To ameliorate the testicular dysfunction induced by ZEN we tested the eventual protective effects of lactic bacteria Lactobacillus plantarum MON03 (LP) on its reprotoxicity. Adult male mice were then treated daily for 2 wks by oral gavage with ZEN and/or LP. The results confirmed that ZEN altered sperm parameters, generated oxidative stress and provoked structural alteration, evidenced by the increased number of abnormal seminiferous tubules and of apoptotic cells, particularly Leydig cells. Interestingly, at molecular level we evaluated, for the first time, the ability of ZEN to alter DAAM1 and PREP protein level and localization. Moreover, the co-treatment with LP, thanks to its capacity to reduce ZEN bioavailability in the gastrointestinal tract, ameliorated all the considered parameters. These results suggest the use of this probiotic as food supplement to prevent/counteract ZEN-induced reprotoxicity.

Immunological effects of AFM1 in experimental subchronic dosing in mice prevented by lactic acid bacteria

AIM

Recently, higher contamination by aflatoxin M1 (AFM1) has been detected in many countries. Unfortunately, many tons of contaminated milk and milk byproducts are removed from the food chain to avoid human contamination; as a consequence of higher economic losses. Fewest number of studies are interested to AFM1 detoxification using lactic acid bacteria.

MATERIALS AND METHODS

In this study, AFM1-degradation using Lactobacillus paracasei BEJ01 (LPBEJ01) was tested in vitro. The preventive effect of LPBEJ01 against AFM1 immunobiological effects in mice are treated orally during 3 weeks with 100 µg AFM1, LPBEJ01 (2 × 10⁹ CFU/ml∼2 mg/kg p.c.) and a mixture of AFM1 and LPBEJ01.

RESULTS

In vitro LPBEJ01 was found able to absorb 98% of AFM1 (100 µg/ml) in liquid medium after 24 h and more than 95% of AFM1 could be eliminated after 24 h in a solid-state fermentation. Animals treated with AFM1 obtained lower body weight than the control ones. The mitogenic response of spleen mononuclear cells (SMCs) in vivo was higher in mice treated with AFM1. The SMC of mice treated with AFM1 produced lower levels of IL-2, higher levels IL-4 and no effect on IL-10 production. The peritoneal macrophages of mice that treated with AFM1 released less H₂O₂, while mice exposed orally with the mixture of AFM1 and LPBEJ01 produced higher levels.

CONCLUSION

LPBEJ01 was safe and it did not have any sign of toxicity. It can be used as an additive for AFM1-detoxification contamination in the food chain in countries suffering from this problem.

Zearalenone nephrotoxicity: DNA fragmentation, apoptotic gene expression and oxidative stress protected by Lactobacillus plantarum MON03

The present study was conducted to determine the abilities of the living Lactobacillus plantarum MON03 cells to degrade Zearalenone (ZEN) in liquid medium, and to elucidate the preventive effect in ZEN-contaminated balb/c mice showing kidney damage. The DNA fragmentation, Bcl-2 and Bax gene expression, caspase-3 activity, mRNA level of inflammation-regulating cytokines and histology of kidney tissues were examined. Female Balb/c mice were divided into four groups (10/group) and treated daily for 2 wk by oral gavage with lactic acid bacteria (L. plantarum MON03) 2 × 10⁹ CFU/L, ~2 mg/kg only, ZEN (40 mg/kg BW) only, ZEN (40 mg/kg BW) + lactic acid bacteria (L. plantarum MON03, 2 × 10⁹ CFU/L, ~2 mg/kg). Control group received vehicle. At the end of experiment, the kidney was collected for the determination of DNA fragmentation, Bcl-2 and Bax gene expression,caspase-3 activity, Malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) content, as well as for any alterations in expression of total antioxidant activity (TAC) and mRNA levels of inflammation-regulating cytokines (e.g., IL-10, IL-6, TNF-alpha). The results indicated that, kidney cells exposure to ZEN led to increased caspase-3 activity, MDA, and IL-10, IL-6, TNF-alpha and Bax mRNA levels, but decreased TAC content and down-regulated expression of GSH-Px and CAT and Bcl-2 mRNA. Co-treatment with ZEN plus LP suppressed the levels of DNA fragmentation; normalized kidney MDA and increased CAT levels, up-regulated expression of GSH-Px and CAT, and normalized mRNA levels of the analyzed cytokines. It's concluded that ZEN might have toxic effects in kidney. Further, it can be seen that use of LP induced protective effects against the oxidative stress and kidney toxicity of ZEN in part through adhesion (and so likely diminished bioavailability).