Sodium butyrate alleviates deoxynivalenol-induced hepatic cholesterol metabolic dysfunction via RORγ-mediated histone acetylation modification in weaning piglets

Background:Cholesterol is an essential component of lipid rafts in cell plasma membrane,which exerts a hepatoprotective role against mycotoxin exposure in pigs,and cholesterol metabolism is vulnerable to epigenetic histone acetylation.Therefore,our present study aimed to investigate whether a histone deacetylase inhibitor(sodium butyrate [NaBu]) could protect the porcine liver from deoxynivalenol(DON) exposure by modulating cholesterol metabolism.Herein,we randomly divided 28 pigs into four groups,which were fed an uncontaminated basal diet,contaminated diet(4 mg DON/kg),uncontaminated diet supplemented with 0.2% NaBu or 4 mg/kg DON contaminated diet(4 mg DON/kg) supplemented with 0.2% NaBu for 28 d.Results:We found that the serum alanine transaminase(ALT),aspartate transaminase(AST),and alkaline phosphatase(ALP) were all increased in pigs exposed to DON,indicative of significant liver injury.Furthermore,the cholesterol content in the serum of DON-exposed pigs was significantly reduced,compared to the healthy Vehicle group.Transcriptome analysis of porcine liver tissues revealed that the cholesterol homeostasis pathway was highly enriched due to DON exposure.In which we validated by qRT-PCR and western blotting that the cholesterol program was markedly activated.Importantly,NaBu effectively restored parameters associated with liver injury,along with the cholesterol content and the expression of key genes involved in the cholesterol biosynthesis pathway.Mechanistically,we performed a ChIP-seq analysis of H3K27ac and showed that NaBu strongly diminished DON-increased H3K27ac genome-wide enrichment.We further validated that the elevated H3K27ac and H3K9ac occupancies on cholesterol biosynthesis genes were both decreased by NaBu,as determined by ChIP-qPCR analysis.Notably,nuclear receptor RORγ,a novel regulator of cholesterol biosynthesis,was found in the hyperacetylated regions.Again,a remarkable increase of RORγ at both mRNA and protein levels in DON-exposed porcine livers was drastically reduced by NaBu.Consistent with RORγ expression,NaBu also hindered RORγ transcriptional binding enrichments on these activated cholesterol biosynthesis genes like HMGCR,SQLE,and DHCR24.Furthermore,we conducted an in vitro luciferase reporter assay to verify that porcine RORγ directly bonds to the promoters of the above target genes.Conclusions:Collectively,our results demonstrate the utility of the natural product Na Bu as a potential anti-mycotoxin nutritional strategy for regulating cholesterol metabolism via RORγ-mediated histone acetylation modification.

Effects of bamboo vinegar powder on growth performance and mRNA expression levels of interleukin-10,interleukin-22,and interleukin-25 in immune organs of weaned piglets

The aim of this study was to explore the effects of bamboo vinegar powder on growth performance,diarrhea situation and mRNA expression levels of cytokines i.e., interleukin-10(IL-10), interleukin-22(IL-22), and interleukin-25(IL-25) in immune organs of weaned piglets, and to accumulate theoretical data for the application of bamboo vinegar powder in weaned piglet production. Forty-five crossbred(Duroc × Landrace × Yorkshire, all male) weaned piglets with similar body weight(6.74 ± 0.17 kg) at 31 days of age were randomly assigned to 5 treatments with 3 replicates per treatment and 3 piglets in each replicate. The five treatments were as follows: CON(a basal diet), ANT(the basal diet + 0.12% antibiotics),BV1(the basal diet + 0.1% bamboo vinegar powder), BV5(the basal diet + 0.5% bamboo vinegar powder),BV10(the basal diet + 1.0% bamboo vinegar powder). This experiment lasted 35 days. The growth performance and diarrhea situation were recorded. The relative mRNA expression levels of IL-10, IL-22 and IL-25 in liver, spleen, duodenum and mesenteric lymph nodes were detected by real-time PCR. Feed:gain of BV5 was significantly lower than that of CON(P < 0.05). In comparison with CON, diarrhea rate and diarrhea index of BV1 and BV5 all tended to decrease(P < 0.1). Compared with CON, mRNA expression level of IL-10 in liver of ANT tended to be lower(P < 0.1) and these of BV1, BV5 and BV10 were significantly reduced(P < 0.05). The mRNA expression levels of IL-10 in duodenum of ANT, BV1, BV5 and BV10 were all lower than those of CON, of which BV10 had significantly decreased IL-10 mRNA expression in duodenum(P < 0.05). The mRNA expression levels of IL-22 in duodenum of ANT, BV1, BV5 and BV10 all tended to be inhibited compared with CON(P < 0.1). With the increase of bamboo vinegar powder dosage, mRNA expression levels of IL-25 in spleen and mesenteric lymph nodes of BV1, BV5 and BV10 tended to be up-regulated. Overall, bamboo vinegar powder could improve growth performance,and regulate mRNA expression levels of IL-10, IL-22 and IL-25 in immune organs of weaned piglets. The dosage at 0.5% showed optimum effects.

Construction of multiple shRNA vectors targeting PEDV and TGEV and production of transgenic SCNT porcine embryos in vitro

Porcine viral diarrhea is an acute and highly contagious enteric disease of pigs that causes huge economic losses worldwide. Porcine epidemic diarrhea virus(PEDV) and transmissible gastroenteritis virus(TGEV) are the main pathogens responsible for piglet viral diarrhea. However, currently there is no speci?c drug available for the effective treatment of viral diarrhea.Therefore, it is necessary to seek an effective method to diminish PEDV and TGEV infection rates. RNA interference has been applied successfully to inhibit the virus replication. It provides a potential strategy for breeding resistant pigs. In this study, four promoters and four short hairpin RNA(shRNA) vectors with LoxP sites at each end of the selectable marker genes were constructed to target PEDV and TGEV. These vectors were then transfected into porcine fetal ?broblasts, G418 resistant transfectants were con?rmed by PCR and transgenic SCNT porcine blastocysts were obtained. These results have paved the way for future production of marker-free transgenic resistant to PEDV and TEGV pigs by SCNT.