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.

Supplementation with sodium butyrate improves growth and antioxidant function in dairy calves before weaning

Background: There is increasing research interest in using short-chain fatty acids(SCFAs) including butyrate as potential alternatives to antibiotic growth promoters in animal production. This study was conducted to evaluate the effects of supplementation of sodium butyrate(SB) in liquid feeds(milk, milk replacer, and the mixture of both)on the growth performance, rumen fermentation, and serum antioxidant capacity and immunoglobins in dairy calves before weaning. Forty healthy female Holstein calves(4-day-old, 40 ± 5 kg of body weight) were housed in individual hutches and randomly allocated to 1 of 4 treatment groups(n = 10 per group) using the RAND function in Excel. The control group was fed no SB(SB0), while the other three groups were supplemented with 15(SB15),30(SB30), or 45(SB45) g/d of SB mixed into liquid feeds offered. The calves were initially fed milk only(days 2 to 20), then a mixture of milk and milk replacer(days 21 to 23), and finally milk replacer only(days 24 to 60).Results: The SB supplementation enhanced growth and improved feed conversion into body weight gain compared with the SB0 group, and the average daily gain increased quadratically with increasing SB supplementation. No significant effect on rumen pH;concentrations of NH_3-N, individual and total VFAs;or acetate:propionate(A:P) ratio was found during the whole experimental period. Serum glutathione peroxidase activity increased linearly with the increased SB supplementation, while the serum concentration of maleic dialdehyde linearly decreased. Serum concentrations of immunoglobulin A, immunoglobulin G, or immunoglobulin M were not affected by the SB supplementation during the whole experimental period.Conclusions: Under the conditions of this study, SB supplementation improved growth performance and antioxidant function in pre-weaned dairy calves. We recommended 45 g/d as the optimal level of SB supplementation mixed into liquid feeds(milk or milk replacer) to improve the growth and antioxidant function of dairy calves before weaning.

Sodium butyrate protects against toxin-induced acute liver failure in rats

BACKGROUND: Acute liver failure(ALF) is a serious clinical syndrome with high mortality. Sodium butyrate has been shown to alleviate organ injury in a wide variety of preclinical models of critical diseases. The aim of this study was to investigate the protective effect of sodium butyrate on ALF in rats.METHODS: All rats were randomly divided into control,model and sodium butyrate treatment groups. Except the control group, the rats were induced ALF animal model by subcutaneous injection of human serum albumin+D- galactosamine+lipopolysaccharide. After induction of ALF,the rats in the treatment group received sodium butyrate(500mg/kg) at 12-hour or 24-hour time point. Fourty-eight hours after ALF induction, the animals were sacrificed and samples were harvested. Serum endotoxin, high mobility group box-1(HMGB1), liver function parameters, tumor necrosis factoralpha(TNF-α) and interferon-gamma(IFN-γ) were measured.The expression of HMGB1 and nuclear factor-kappa B(NF-κB)p65 protein in liver tissue was detected by Western blotting. The histological changes of liver and intestine were examined. The survival duration was also observed.RESULTS: Serum endotoxin, alanine aminotransferase, HMGB1,TNF-α and IFN-γ were significantly increased and the liver histology showed more severe histopathological injury in the model group compared with the control group(P<0.05).Compared to the model group, sodium butyrate treatment significantly improved the histopathological changes in the liver and intestine, reduced serum endotoxin and inflammatory cytokines, suppressed HMGB1 and NF-кB p65 proteins in liver tissue, and prolonged the survival duration regardless of treatment at 12 hours or 24 hours after induction of ALF(P<0.05).CONCLUSIONS: Sodium butyrate protected the liver from toxin-induced ALF in rats. The mechanisms may be due to direct hepatoprotection and decreased intestinal permeability.

Sodium Butyrate Induces Apoptosis of Human Colon Cancer Cells by Modulating ERK and Sphingosine Kinase 2

Objective To investigate the role of extracellular signal-regulated kinase （ERK） in apoptosis of human colon cancer （HCT116） cells. Methods After the HCT116 cells were pretreated with specific ERK inhibitor （U0126） or specific siRNA and exposed to 10 mmol/L sodium butyrate （NaBT） for 24 h, their apoptosis was detected by flow cytometry, levels of SphK2 and ERK protein were measured by Western blot, and translocation of SphK2 was assayed by immunofluorescence microscopy. Results The U0126 and siRNAs specific for SphK2 blocked the export of SphK2 from nuclei to cytoplasm and increased the apoptosis of HCT116 cells following NaBT exposure. Over-expression of PKD decreased NaBT-induced apoptosis of HCT116 cells, which was reversed by U0126. Furthermore, transfection of HCT116 cells with constitutively activated PKD plasmids recovered the UO126-blocked export of SphK2. Conclusion ERK regulates the export of SphK2 and apoptosis of HCT116 cells by modulating PKD. Modulation of these molecules may help increase the sensitivity of colon cancer cells to the physiologic anti-colon cancer agent, NaBT.

Protective effects of sodium butyrate on rotavirus inducing endoplasmic reticulum stress-mediated apoptosis via PERK-eIF2αsignaling pathway in IPEC-J2 cells

Background:Rotavirus(RV)is a major pathogen that causes severe gastroenteritis in infants and young animals.Endoplasmic reticulum(ER)stress and subsequent apoptosis play pivotal role in virus infection.However,the protective mechanisms of intestinal damage caused by RV are poorly defined,especially the molecular pathways related to enterocytes apoptosis.Thus,the aim of this study was to investigate the protective effect and mechanism of sodium butyrate(SB)on RV-induced apoptosis of IPEC-J2 cells.Results:The RV infection led to significant cell apoptosis,increased the expression levels of ER stress(ERS)markers,phosphorylated protein kinase-like ER kinase(PERK),eukaryotic initiation factor 2 alpha(eIF2α),caspase9,and caspase3.Blocking PERK pathway using specific inhibitor GSK subsequently reversed RV-induced cell apoptosis.The SB treatment significantly inhibited RV-induced ERS by decreasing the expression of glucose regulated protein 78(GRP78),PERK,and eIF2α.In addition,SB treatment restrained the ERS-mediated apoptotic pathway,as indicated by downregulation of C/EBP homologous protein(CHOP)mRNA level,as well as decreased cleaved caspase9 and caspase3 protein levels.Furthermore,siRNA-induced GPR109a knockdown significantly suppressed the protective effect of SB on RV-induced cell apoptosis.Conclusions:These results indicate that SB exerts protective effects against RV-induced cell apoptosis through inhibiting ERS mediated apoptosis by regulating PERK-eIF2αsignaling pathway via GPR109a,which provide new ideas for the prevention and control of RV.

Effect and Comparison of Sodium Butyrate and Trichostatin A on the Proliferation/Differentiation of K562

In order to explore the molecular mechanisms of sodium butyrate and trichostatin A on K562 cell proliferation/differentiation, K562 cells were grown in the absence or presence of sodium butyrate or trichostatin A The percentage of viable cells was determined by trypan blue exclusion Differentiation was determined by nitro-blue tetrazolium (NBT) reduction and cell surface adhesion molecules analyzed by FACS Cell cycle distribution was studied after DNA staining by propidium iodide Cell cycle regulatory proteins were detected by Western blot and reverse transcription-polymerase chain reaction The results showed that sodiun butyrate blocked cells mainly at the G0/G1 phase of the cell cycle, whereas trichostatin A arrested the cells at G2 phase Sodium butyrate could down-regulate the mRNA expression of cyclin D1, but not affect its protein expression; down-regulate the protein expression of cyclin D3, but not affect its mRNA expression Trichostatin A showed similar effects on cyclin D1 and D3 as sodium butyrate Both sodium butyrate and trichostatin A could stimulate p21 expression of K562 cells at mRNA and protein levels It may be concluded that sodium butyrate and trichostatin A could promote the proliferation/differentiation of the K562 cells, which might be contributed to the induced expression of cyclin D3 and p21 proteins

The Effect of Sodium Butyrate in Combination with ATRA on the Proliferation/Differentiation of SKM-1

To explore the molecular mechanisms of sodium butyrate working on SKM-1 cell proliferation/differentiation and to study its synergistic effect with all-trans retinoic acid (ATRA), SKM-1 cells were grown in the absence or presence of sodium butyrate and/or ATRA. The percentage of viable cells was determined by trypan blue exclusion. Differentiation was determined by nitroblue tetrazolium (NBT) reduction and cell surface adhesion molecules was analyzed by FACS. Cell cycle distribution was examined after DNA staining by propidium iodide. D-type cyclins, cdks and P21 mRNA were studied by reverse transcription-polymerase chain reaction. Our results showed that sodiun butyrate and/or ATRA blocked cells mainly in the G 0/G 1 phase of the cell cycle. ATRA inhibited the mRNA expression of CDK6, CDK4, cyclinD3 and cyclinD1. Sodium butyrate inhibited the mRNA expression of CDK2, cyclinD2 and cyclinD1. ATRA and sodium butyrate inhibited the mRNA expression of CDK6, CDK4, CDK2, cyclinD1, cyclinD2 and cyclinD3. Both ATRA and/or sodium butyrate stimulated p21 expression at the mRNA levels. Our results suggest that the effect of sodium butyrate on cell proliferation/differentiation might be linked to its ability to induce expression of p21 mRNA and inhibit the cyclin-cdk complexes. Our observations support the notion that the sodium butyrate works synergistically with ATRA.

MODULATION OF MDR-1 GENE IN HUMAN BREAST CANCER CELLS BY SODIUM BUTYRATE AND DMSO

Objective: To analyze the regulation effect of MDR-1 gene in human breast cancer cell by the differentiating agents, sodium butyrate and dimethyl sulfoxide. Methods: 1. A sensitive assay, RT-PCR, was used to measure the mRNA level before and after the treatment of sodium butyrate, DMSO, using β-actin as control; 2. Evaluated the effect of sodium butyrate, DMSO on MDR-1 gene expression of human breast cancer at the protein level by immunoflow cytometry; 3. P-glycoprotein function was examined after accumulation of the fluorescent drug, Phodamine-123, by flow cytometry; 4. Chemosensitivity to doxorubicin was analyzed using the MTT assay. Results: Sodium butyrate and DMSO were found to increase the MDR characteristics on MDR-1 gene, MDR-1 expression levels, P-glycoprotein function and chemosensitivity to doxorubicin. Conclusion: sodium butyrate, DMSO can modulate the MDR-1 gene at gene level, protein level, protein function level and cell level.

Contribution of Decreased Expression of Ku70 to Enhanced Radiosensitivity by Sodium Butyrate in Glioblastoma Cell Line(U251)

The present study investigated the enhanced radiosensitivity of U-251 cells induced by sodium butyrate（NaB） and its possible mechanisms.Increased radiosensitivity of U251 cells was examined by clonogenic cell survival assays.The expression of Ku70 mRNA and protein was detected by using RT-PCR and Western blotting respectively.γ-H2AX foci were measured at different time points after ionizing irradiation alone or combined with NaB treatment.The results showed that cell survival rate was significantly reduced,both D0 and Dq values were decreased（D0：1.43 Gy vs.1.76 Gy;Dq：1.22 Gy vs.2.05 Gy） after the combined treatment as compared with irradiation alone,and sensitivity enhancing ratio（SER） reached 1.23.The average number of γ-H2AX foci per cell receiving the combined treatment was significantly increased at different time points,and the expression levels of Ku70 mRNA and protein were suppressed by NaB in a dose-dependent manner.It was concluded that enhanced radiosensitivity induced by NaB involves an inhibited expression of Ku70 and an increase in γ-H2AX foci,which suggests decreased ability in DSB repair.

Effects of Nano-sustained Release Sodium Butyrate on Growth and Intestinal Cell Proliferation of Grass Carps

Taking grass carps with the initial weight of about 20g as the research object,the basic feeds of grass carps were added with0.0%,0.1%,0.3%,0.6%,0.8%,and 1% of nano-sustained release sodium butyrate to prepare 6 types of experimental feeds with equal nitrogen and energy.The effects of different concentrations of nano-sustained release sodium butyrate were surveyed on growth and intestinal cell proliferation of grass carps.The experiment was carried out in cages with 50 carps per cage,and each treatment was repeated 3 times for60 days.Experimental results indicated that the addition of nano-sustained release sodium butyrate significantly promoted the growth of grass carps and significantly increased the ratio of intestinal villus to crypt depth.When the addition of nano-sustained release sodium butyrate was0.6%,the weight increase rate,specific growth rate,fullness and intestinal villus height of grass carps were the highest,which was significantly higher than that of the control group(P < 0.05).The study results indicated that addition of appropriate amount of nano-sustained release sodium butyrate can promote the growth of grass carps through increasing the intestinal villus height,and the suitable addition dosage was0.6%.

Inhibition of mouse B16 melanoma by Sodium butyrate correlated to tumor associated macrophages differentiation suppression

Objective: As one member of the histone deacetylase inhibitor (HDACi) family, Sodium butyrate (NaB) was found out that could be used as a differentiation inducer of much cancer cell. But its effects on tumor microenvironment cells are not well recognized. The goal of this research is to investigate the effect of NaB on B16 melanoma and analysis its relevant mechanism. Methods: We observed the effect of sodium butyrate on B16 melanoma in vivo and in vitro. MTT method was performed to detect cell apoptosis rate after treatment. Tumor associated macrophage infiltration condition was detected by flow cytometry. Western-blotting and immunohistochemical method were used to detect the expression of tumor associated macrophage cytokines. Results: A certain concentration of sodium butyrate could effectively inhibit B16 melanoma growth in vivo and in vitro. Compared with the control group (45.00 ± 3.43%), macrophage differentiation in the 1.0g / kg group (37.54 ± 2.34%), 2.0g / kg group (41.62 ± 3.10%) and 3.0g / kg group (29.28 ± 4.42%) group were all inhibited to varying degrees. The inhibitory effect was most significant in the 5.0 g / kg group (19.92 ± 4.80%), and the difference was statistically significant (P <0.01).At the same time we observed the relevant macrophage factors were down-regulated compared to the control. Conclusion: Sodium butyrate could effectively inhibit B16 melanoma growth through suppressing tumor associated macrophage proliferation and reduce relevant pro-tumor macrophage factors expression, which may help to promote the clinical study of melanoma epigenetic therapy.

Coated sodium butyrate ameliorates high‑energy and low‑protein diet induced hepatic dysfunction via modulating mitochondrial dynamics, autophagy and apoptosis in laying hens

Background Fatty liver hemorrhagic syndrome(FLHS),a fatty liver disease in laying hens,poses a grave threat to the layer industry,stemming from its ability to trigger an alarming plummet in egg production and usher in acute mortality among laying hens.Increasing evidence suggests that the onset and progression of fatty liver was closely related to mitochondria dysfunction.Sodium butyrate was demonstrated to modulate hepatic lipid metabolism,alle-viate oxidative stress and improve mitochondrial dysfunction in vitro and mice models.Nevertheless,there is limited existing research on coated sodium butyrate(CSB)to prevent FLHS in laying hens,and whether and how CSB exerts the anti-FLHS effect still needs to be explored.In this experiment,the FLHS model was induced by administering a high-energy low-protein(HELP)diet in laying hens.The objective was to investigate the effects of CSB on alleviating FLHS with a focus on the role of CSB in modulating mitochondrial function.Methods A total of 288 healthy 28-week-old Huafeng laying hens were arbitrarily allocated into 4 groups with 6 replicates each,namely,the CON group(normal diet),HELP group(HELP diet),CH500 group(500 mg/kg CSB added to HELP diet)and CH750 group(750 mg/kg CSB added to HELP diet).The duration of the trial encompassed a period of 10 weeks.Results The result revealed that CSB ameliorated the HELP-induced FLHS by improving hepatic steatosis and patho-logical damage,reducing the gene levels of fatty acid synthesis,and promoting the mRNA levels of key enzymes of fatty acid catabolism.CSB reduced oxidative stress induced by the HELP diet,upregulated the activity of GSH-Px and SOD,and decreased the content of MDA and ROS.CSB also mitigated the HELP diet-induced inflammatory response by blocking TNF-α,IL-1β,and F4/80.In addition,dietary CSB supplementation attenuated HELP-induced activation of the mitochondrial unfolded protein response(UPRmt),mitochondrial damage,and decline of ATPase activity.HELP diet decreased the autophagosome formation,and downregulated LC3B but upregulated p62 protein expression,which CSB administration reversed.CSB reduced HELP-induced apoptosis,as indicated by decreases in the Bax/Bcl-2,Caspase-9,Caspase-3,and Cyt C expression levels.Conclusions Dietary CSB could ameliorate HELP diet-induced hepatic dysfunction via modulating mitochondrial dynamics,autophagy,and apoptosis in laying hens.Consequently,CSB,as a feed additive,exhibited the capacity to prevent FLHS by modulating autophagy and lipid metabolism.

Sodium butyrate promotes gastrointestinal development of preweaning bull calves via inhibiting inflammation,balancing nutrient metabolism,and optimizing microbial community functions

Butyrate promotes the growth and gastrointestinal development of calves.But,the mechanisms behind its effects on signaling pathways of the gastrointestinal tract and rumen microbiome is unclear.This study aimed to reveal transcriptomic pathways of gastrointestinal epithelium and microbial community in response to butyrate supplementation in calves fed a high fiber starter.Fourteen Holstein bull calves(39.9±3.7 kg,14 d of age)were assigned to 2 groups(sodium butyrate group,SB;control group,Ctrl).The SB group received 0.5%SB supplementation.At d 51,the calves were slaughtered to obtain samples for analysis of the transcriptome of the rumen and jejunum epithelium as well as ruminal microbial metagenome.Sodium butyrate supplementation resulted in a higher performance in average daily gain and development of jejunum and rumen papillae.In both the rumen and jejunum epithelium,SB downregulated pathways related to inflammation including NF-κB(PPKCB,CXCL8,CXCL12),interleukin-17(IL17A,IL17B,MMP9),and chemokine(CXCL12,CCL4,CCL8)and up-regulated immune pathways including the intestinal immune network for immunoglobulin A(IgA)production(CD28).Meanwhile,in the jejunum epithelium,SB regulated pathways related to nutritional metabolism including nitrogen metabolism(CA1,CA2,CA3),synthesis and degradation of ketone bodies(HMGCS2,BDH1,LOC100295719),fat digestion and absorption(PLA2G2F,APOA1,APOA4),and the PPAR signaling pathway(FABP4,FABP6,CYP4A11).The metagenome showed that SB greatly increased the relative abundance of Bacillus subtilis and Eubacterium limosum,activated ruminal microbial carbohydrate metabolism pathways and increased the abundance of carbohydrate hydrolysis enzymes.In conclusion,butyrate exhibited promoting effects on growth and gastrointestinal development by inhibiting inflammation,enhancing immunity and energy harvesting,and activating microbial carbohydrate metabolism.These findings provide new insights into the potential mechanisms behind the beneficial effects of butyrate in calf nutrition.

Multi-omics Data Reveal the Effect of Sodium Butyrate on Gene Expression and Protein Modification in Streptomyces

Streptomycetes possess numerous gene clusters and the potential to produce a large amount of natural products.Histone deacetylase(HDAC)inhibitors play an important role in the regulation of histone modifications in fungi,but their roles in prokaryotes remain poorly understood.Here,we investigated the global effects of the HDAC inhibitor,sodium butyrate(SB),on marine-derived Streptomyces olivaceus FXJ 8.021,particularly focusing on the activation of secondary metabolite biosynthesis.The antiSMASH analysis revealed 33 secondary metabolite biosynthetic gene clusters(BGCs)in strain FXJ 8.021,among which the silent lobophorin BGC was activated by SB.Transcriptomic data showed that the expression of genes involved in lobophorin biosynthesis(ge00097–ge00139)and CoA-ester formation(e.g.,ge02824),as well as the glycolysis/gluconeogenesis pathway(e.g.,ge01661),was significantly up-regulated in the presence of SB.Intracellular CoA-ester analysis confirmed that SB triggered the biosynthesis of CoA-ester,thereby increasing the precursor supply for lobophorin biosynthesis.Further acetylomic analysis revealed that the acetylation levels on 218 sites of 190 proteins were up-regulated and those on 411 sites of 310 proteins were down-regulated.These acetylated proteins were particularly enriched in transcriptional and translational machinery components(e.g.,elongation factor GE04399),and their correlations with the proteins involved in lobophorin biosynthesis were established by protein–protein interaction network analysis,suggesting that SB might function via a complex hierarchical.

Sodium butyrate activates HMGCS2 to promote ketone body production through SIRT5-mediated desuccinylation

Ketone bodies have beneficial metabolic activities,and the induction of plasma ketone bodies is a health promotion strategy.Dietary supplementation of sodium butyrate(SB)is an effective approach in the induction of plasma ketone bodies.However,the cellular and molecular mechanisms are unknown.In this study,SB was found to enhance the catalytic activity of 3-hydroxy-3-methylglutaryl-CoA synthase 2(HMGCS2),a rate-limiting enzyme in ketogenesis,to promote ketone body production in hepatocytes.SB administrated by gavage or intraperitoneal injection significantly induced bloodβ-hydroxybutyrate(BHB)in mice.BHB production was induced in the primary hepatocytes by SB.Protein succinylation was altered by SB in the liver tissues with down-regulation in 58 proteins and up-regulation in 26 proteins in the proteomics analysis.However,the alteration was mostly observed in mitochondrial proteins with 41%down-and 65%up-regulation,respectively.Succinylation status of HMGCS2 protein was altered by a reduction at two sites(K221 and K358)without a change in the protein level.The SB effect was significantly reduced by a SIRT5 inhibitor and in Sirt5-KO mice.The data suggests that SB activated HMGCS2 through SIRT5-mediated desuccinylation for ketone body production by the liver.The effect was not associated with an elevation in NAD+/NADH ratio according to our metabolomics analysis.The data provide a novel molecular mechanism for SB activity in the induction of ketone body production.

Dietary supplementation of sodium butyrate enhances lactation performance by promoting nutrient digestion and mammary gland development in dairy cows

This experiment was to evaluate the influence of sodium butyrate(SB)addition on milk production,ruminal fermentation,nutrient digestion,and the development and metabolism regulation of the mammary gland in dairy cows.Forty Holstein dairy cows averaging 710±18.5 kg body weight,72.8±3.66 d in milk(DIM),and 41.4±1.42 kg/d milk production were divided into four treatments blocked by DIM and milk production.Treatments were control group,low SB,medium SB,and high SB with 0,100,200 and 300 g/d of SB addition per cow,respectively.The study lasted for 105 d.Production of milk,milk protein and lactose quadratically increased(P<0.05),while fat-corrected milk,energycorrected milk and milk fat yields linearly increased(P<0.05)with increasing SB addition.The digestibility of dietary dry matter,organic matter,and crude protein linearly increased(P<0.05),whereas the digestibility of ether extract,neutral detergent fibre,and acid detergent fibre quadratically increased(P<0.05).Ruminal pH quadratically decreased(P=0.04),while total volatile fatty acids(VFA)quadratically increased(P=0.03)with increasing SB addition.The acetic acid to propionic acid ratio increased(P=0.03)linearly due to the unaltered acetic acid molar percentage and a linear decrease in propionic acid molar percentage.Ruminal enzymatic activity of carboxymethyl-cellulase and a-amylase,populations of total bacteria,total anaerobic fungi,total protozoa,Ruminococcus albus,R.flavefaciens,Butyrivibrio fibrisolvens,Fibrobacter succinogenes,and Ruminobacter amylophilus linearly increased(P<0.05).Blood glucose,urea nitrogen,and non-esterified fatty acids linearly decreased(P<0.05),while total protein concentration linearly increased(P=0.04).Moreover,the addition of SB at 200 g/d promoted(P<0.05)mRNA and protein expression of PPARγ,SREBF1,ACACA,FASN,SCD,CCNA2,CCND1,PCNA,Bcl-2,GPR41,and the ratios of p-Akt/Akt and p-mTOR/mTOR,but decreased(P<0.05)mRNA and protein expressions of Bax,caspase-3,and caspase-9.The results suggest that milk production and milk fat synthesis increased with SB addition by stimulating rumen fermentation,nutrient digestion,gene and protein expressions concerned with milk fat synthesis and mammary gland development.

Effects of dietary sodium butyrate on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish (Pelteobagrus fulvidraco)

An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate(SB)on growth,digestive enzymes,body composition and nutrient retention-related gene expression of juvenile yellow catfish(Pel-teobagrus fulvidraco).Five isonitmgenous and isolipidic diets(420 g/kg protein and 90 g/kg lipid)were formulated to contain 0(control),250,500,1,000 or 2,000 mg/kg SB.Triplicate groups of 40 fish(BW=1.26±0.01 g)per tank(300-L cylindrical fiberglass tanks)for each diet were fed to apparent satiation twice daily.Stomach,hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses.A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapa-mycin(TOR)and lipoprotein lipase(LPL)in the hepatopancreas and intestine.Fish fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control(P<0.05).Dietary SB inclusion did not alter activities of intestinal amylase,creatine kinase and sodium-potassium adenosine triphosphatase(Na+/K+-ATPase),but increased activities of hepatic trypsin,stomachic lipase,intestinal lipase,alkaline phosphatase and y-glutamyl trans-peptidase for fish fed 1,000 mg/kg SB compared to the control(P<0.05).Intestine length index,intestine somatic index,fold height and muscular thickness of distal intestine were significantly higher in 1,000 mg/kg SB groups compared to the control(P<0.05).Significantly higher levels of whole-body crude protein,ash,calcium,phosphorus,nutrition retention and relative mRNA of intestinal TOR were observed in 1,000 mg/kg SB group(P<0.05).Whole-body lipid content and hepatopancreas LPL mRNA expression in 2,000 mg/kg SB gmup were significantly higher than the control(P<0.05).Relative mRNA levels of intestinal LPL and hepatopancreas TOR were significantly higher in the 500 mg/kg SB group compared to those in other groups(P<0.05).The increased growth performance,digestive enzymes and nutrient retention in fish fed the diets supplemented with SB at 500 and 1,000 mg/kg suggests that SB can be a desirable growth promoter as an antibiotic alternative in diets.

Targeting BMI-1-mediated epitheliale-mesenchymal transition to inhibit colorectal cancer liver metastasis

Liver is the most common metastatic site for colorectal cancer(CRC),there is no satisfied approach to treat CRC liver metastasis(CRCLM).Here,we investigated the role of a polycomb protein BMI-1 in CRCLM.Immunohistochemical analysis showed that BMI-1 expression in liver metastases was upregulated and associated with T4 stage,invasion depth and right-sided primary tumor.Knockdown BMI-1 in high metastatic HCT116 and LOVO cells repressed the migratory/invasive phenotype and reversed epithelialemesenchymal transition(EMT),while BMI-1 overexpression in low metastatic Ls174 T and DLD1 cells enhanced invasiveness and EMT.The effects of BMI-1 in CRC cells were related to upregulating snail via AKT/GSK-3βpathway.Furthermore,knockdown BMI-1 in HCT116 and LOVO cells reduced CRCLM using experimental liver metastasis mice model.Meanwhile,BMI-1 overexpression in Ls174 T and DLD1 significantly increased CRCLM.Moreover,sodium butyrate,a histone deacetylase and BMI-1 inhibitor,reduced HCT116 and LOVO liver metastasis in immunodeficient mice.Our results suggest that BMI-1 is a major regulator of CRCLM and provide a potent molecular target for CRCLM treatment.

丁酸钠通过GPR43/β-arrestin-2/NF-κB通路在一定程度上预防脂多糖诱导的肝损伤

背景:丁酸盐在多种器官的炎症损伤中起调节作用。然而,其在急性肝损伤中的作用尚未得到充分研究。本研究旨在探讨丁酸盐与脂多糖(LPS)诱导的急性肝损伤的关系及其相关信号通路。方法:选取G蛋白偶联受体43敲除型(GPR43-KO)和野生型(GPR43-WT)雌性C57BL/6小鼠,通过腹腔注射LPS(5 mg/kg)建立LPS诱导的急性肝损伤小鼠模型。在建模前腹腔注射丁酸钠(500 mg/kg)进行预处理。通过血清标记物、组织形态学及TUNEL细胞凋亡检测评估肝损伤程度。同时采用ELISA和RT-PCR检测促炎因子表达水平。在转染GPR43 siRNA及对照组的RAW264.7细胞株中,予丁酸钠(4 mol/mL)预处理,半小时后予LPS(1μg/mL)建立细胞模型。通过RT-PCR检测促炎因子表达量,并通过Western-blot检测TLR4/NF-κB信号通路中的关键信号分子(TLR4、TRAF6、IKKβ、IкBα、phospho-IкBα、p65、phospho-p65)的蛋白表达量,以评估肝脏炎症水平。采用免疫共沉淀法检测GPR43与arrestin-2之间的相互作用。结果:丁酸钠可逆转LPS诱导的肝组织形态学改变和升高的丙氨酸氨基转移酶(ALT)、天冬氨酸氨转移酶(AST)、髓过氧化物酶(MPO)、TUNEL凋亡水平、促炎因子(如TNF-α和IL-6)。与GPR43-WT相比,丁酸钠在GPR43-KO小鼠和GPR43 siRNA RAW264.7细胞中的保护作用减弱。丁酸钠下调RAW264.7细胞TLR4/NF-κB通路中部分信号分子的表达(如phospho-IκBα和phospho-p65),同时可增强GPR43与β-arrestin-2,以及IкBα与β-arrestin-2的相互作用。结论:丁酸钠可通过调控GPR43/β-arrestin-2/NF-κB信号通路抑制炎症反应,从而减轻LPS诱导的肝损伤。