The protective effects of a fermented substance from Saccharomyces cerevisiae on carbon tetrachloride-induced liver damage in rats

Elucidating the causal association between gut microbiota and intrahepatic cholangiocarcinoma through Mendelian randomization analysis

Background

Intrahepatic cholangiocarcinoma (ICC) is an aggressive liver cancer with poor prognosis. The gut microbiota has been linked to ICC, but evidence for causality is lacking. Elucidating causal gut microbiota-ICC links could inform prevention and treatment strategies.

Materials and methods

We performed a bidirectional two-sample Mendelian randomization (MR) study to investigate causal associations between gut microbiota and ICC risk. Genome-wide significant single nucleotide polymorphisms (SNPs) associated with gut microbiota abundances were utilized as instrumental variables (IVs). Multiple methods assessed causality and sensitivity analyses evaluated result robustness. Bioinformatics analysis of genetic loci linked to gut microbiota and ICC examined potential mechanisms.

Results

Genetically predicted increases in Veillonellaceae, Alistipes, Enterobacteriales, and Firmicutes were suggestively associated with higher ICC risk, while increases in Anaerostipes, Paraprevotella, Parasutterella, and Verrucomicrobia appeared protective. Bioinformatics analysis revealed differentially expressed genes near gut microbiota-associated loci may influence ICC through regulating pathways and tumor immune microenvironment.

Conclusion

Our findings provide suggestive evidence for causal links between specific gut microbiota and ICC risk.

Combination of Selenomethionine and N-Acetylcysteine Alleviates the Joint Toxicities of Aflatoxin B1 and Ochratoxin A by ERK MAPK Signal Pathway in Porcine Alveolar Macrophages

Our previous studies showed that aflatoxin B1 (AFB1) and ochratoxin A (OTA) could trigger joint immune toxicity. Little is known about the combined effects of selenomethionine (SeMet) and N-acetylcysteine (NAC) on the joint toxicities of the two toxins. In this study, results showed that SeMet or NAC alone or in combination significantly alleviated the downswing of cell viability, glutathione production, and phagorytosis induced by AFB1 and OTA in porcine alveolar macrophages. The uptrend of lactate dehydrogenase activities, apoptosis, reactive oxygen species levels, and the relative mRNA of inflammatory cytokines triggered by the two toxins was decreased. Combination of them was more effective than single application. Knockdown of p38, c-JUN N-terminal kinase (JNK), or extracellular signal-regulated kinase (ERK) via use of the corresponding specific siRNA could alleviate the joint toxicities of AFB1 and OTA. However, the ERK but not p38 or JNK pathway was involved in the protection of SeMet and NAC against the immunotoxicity. In conclusion, combination of SeMet and NAC might be a new therapeutic orientation for preventing the joint toxicities induced by AFB1 and OTA.

Protective effects of selenium-glutathione-enriched probiotics on CCl4-induced liver fibrosis

Hepatic fibrosis is a common pathological basis of liver cirrhosis and hepatocellular carcinomas. So, prevention and treatment of liver fibrosis is one of the crucial therapeutic goals in hepatology. Organic selenium, glutathione or probiotics supplementation could ameliorate hepatic fibrosis, respectively. The purpose of this study is to develop a novel selenium-glutathione-enriched probiotics (SGP) and to investigate its protective effect on CCl₄-induced liver fibrosis in rats. Yeast strains with the high-yield glutathione were isolated and identified by analysis of 26S ribosomal DNA sequences. The fermentation parameters of SGP were optimized through single-factor, Plackett-Burman (PB) design and response surface methodology (RSM). The final SGP contained 38.4 μg/g of organic selenium, 34.1 mg/g of intracellular glutathione, approximately 1×10¹⁰ CFU/g live Saccharomyces cerevisiae and 1×10¹² CFU/g live Lactobacillus acidophilus. SGP had better protective effects on liver fibrosis than selenium, glutathione or probiotics, respectively. The hepatic silent information regulator 1 (SIRT1) level was down-regulated and oxidative stress, endoplasmic reticulum (ER) stress, inflammation and phosphorylated MAPK was increased in CCl₄-treated rats. However, SGP can significantly reverse these changes caused by CCl₄. Our findings suggest that SGP was effective in attenuating liver fibrosis by the activation of SIRT1 signaling and attenuating hepatic oxidative stress, ER stress, inflammation and MAPK signaling.

Protective effects of Selenium-enriched probiotics on carbon tetrachloride-induced liver fibrosis in rats

This study aimed to investigate the effects of Se-enriched probiotics (SP) on the liver fibrosis induced by CCl4 in rats. The results showed that SP significantly decreased serum alanine aminotransferase (87.0 ± 1.96 U/L), aspartate aminotransferase (101 ± 3.13 U/L), hepatic hydroxyproline (898 ± 72.5 μg/g), and malondialdehyde (2.39 ± 0.34 nmol/mg) levels, but increased glutathione peroxidase (37.2 ± 3.19 U/mg), superoxide dismutase (201 ± 19.2 U/mg), and glutathione levels (3.32 ± 0.25 mg/g) (P < 0.05) in rats treated by CCl4. SP suppressed hepatic inflammation and necrosis induced by CCl4. Moreover, SP significantly reduced the expression of α-smooth muscle actin, collagen, TGF-β1, TIMP-1, and inflammation-related gene and induced apoptosis of activated hepatic stellate cells (P < 0.05) in rats treated by CCl4. Our results suggest that SP could protect the liver from fibrosis by attenuating hepatic oxidative stress, suppressing hepatic inflammation, and inducing apoptosis of hepatic stellate cells.

Hepatoprotective action of Radix Paeoniae Rubra aqueous extract against CCl4-induced hepatic damage

In the present study the capacity of Radix Paeoniae Rubra aqueous extract (RPRAE) as an antioxidant to protect against carbon tetrachloride (CCl₄)-induced oxidative stress and hepatotoxicity in Wistar rats was investigated. Six groups of rats were used. Radix Paeoniae Rubra aqueous extract (100 or 200 or 300 mg/kg of bw) or bifendate (100 mg/kg of bw) were given daily by gavage to the animals on 28 consecutive days to elucidate the protective effects against CCl₄-induced hepatotoxicity. The 20% CCl₄/olive oil was gavage of gastric tube twice a week (on the third and seventh days of each week). The animals of normal control group were given only vehicle. The animals of CCl₄-treated group were administered with CCl₄ twice a week (on the third and seventh days of each week) and with vehicle on rest of the days. The test materials were found effective as hepatoprotective agents, as evidenced by plasma and liver biochemical parameters. Therefore, the results of this study show that Radix Paeoniae Rubra aqueous extract can protect the liver against CCl₄-induced oxidative damage in rats, and the hepatoprotective effects might be correlated with its antioxidant and free radical scavenger effects.