Sensing of commensal organisms by the intracellular sensor NOD1 mediates experimental pancreatitis.

The intracellular sensor NOD1 has important host-defense functions relating to a variety of pathogens. Here, we showed that this molecule also participates in the induction of a noninfectious pancreatitis via its response to commensal organisms. Pancreatitis induced by high-dose cerulein (a cholecystokinin receptor agonist) administration depends on NOD1 stimulation by gut microflora. To analyze this NOD1 activity, we induced pancreatitis by simultaneous administration of a low dose of cerulein (that does not itself induce pancreatitis) and FK156, an activator of NOD1 that mimics the effect of gut bacteria that have breached the mucosal barrier. The pancreatitis was dependent on acinar cell production of the chemokine MCP-1 and the intrapancreatic influx of CCR2(+) inflammatory cells. Moreover, MCP-1 production involved activation of the transcription factors NF-κB and STAT3, each requiring complementary NOD1 and cerulein signaling. These studies indicate that gut commensals enable noninfectious pancreatic inflammation via NOD1 signaling in pancreatic acinar cells.

Sodium butyrate attenuated iE-DAP induced inflammatory response in the mammary glands of dairy goats fed high-concentrate diet.

BACKGROUND: Long-term high-concentrate (HC) diet feeding increased bacterial endotoxins, which translocated into the mammary glands of dairy goats and induced inflammatory response. γ-d-Glutamyl-meso-diaminopimelic acid (iE-DAP), bacterial peptidoglycan component, triggered inflammatory response through activating nucleotide oligomerization domain protein 1 (NOD1) signaling pathway. While dietary supplemented with sodium butyrate (SB) relieved inflammatory response and improved animal health and production. To investigate the effects and the mechanisms of action of SB on the inflammatory response in the mammary glands of dairy goats fed HC diet, 12 Saanen dairy goats were randomly assigned into HC group and SB regulated (BHC) group. RESULTS: The results showed that SB supplementation attenuated ruminal pH decrease caused by HC diet in dairy goats resulting in a decrease of proinflammatory cytokines and iE-DAP plasma concentration and the mRNA expression of NOD1 and other inflammation-related genes. The protein levels of NOD1, NF-κB p65 and NF-κB pp65 were decreased by the SB supplementation. The expression of histone deacetylase 3 (HDAC3) was also inhibited by the SB supplementation. Meanwhile, the chromatin compaction ratios and DNA methylation levels of NOD1 and receptor-interacting protein 2 (RIP2) of BHC group were upregulated. CONCLUSION: Collectively, the SB supplementation mitigated the inflammatory response in the mammary glands of dairy goats during HC-induced subacute ruminal acidosis (SARA) by inhibiting the activation of the NOD1/NF-κB signaling pathway through the decrease of the iE-DAP concentration in the rumen fluid and plasma and HDAC3 expression. DNA methylation and chromatin remodeling also contributed to the anti-inflammatory effect of SB. © 2020 Society of Chemical Industry.

Sodium Butyrate Mitigates iE-DAP Induced Inflammation Caused by High-Concentrate Feeding in Liver of Dairy Goats.

The aim of this study is to explore the impact of sodium butyrate on d-glutamyl- meso-diaminopimelic acid (iE-DAP)-induced liver inflammation in dairy goats during subacute ruminal acidosis (SARA) caused by high-concentrate feed. To achieve this aim, 12 lactating dairy goats were randomly divided into two groups: a high-concentrate feed group ( n = 6, concentrate/forage = 6:4) as the control group and a sodium butyrate (SB) with high-concentrate feed group ( n = 6, concentrate/forage = 6:4, with 1% SB by wt.) as the treatment group. A rumen pH below 5.6 lasted for at least 4 h/d due to long-term HC feeding. The concentration of iE-DAP was significantly lower (11.67 ± 3.85 µg/mL, and 7.74 ± 1.46 µg/mL, at the fourth h and sixth h of feeding, respectively) in the SB-treated group than that in the HC group (51.45 ± 5.71 µg/mL, and 18.31 ± 3.83 µg/mL, at the fourth h and sixth h of feeding, respectively). Meanwhile, SB significantly suppressed the mRNA expression of inflammatory genes (NOD1, RIPK2, TAK1, NF-κB/p65, ERK, JNK2, p38, IL-1ß, TNF-α, CCL5, CCL20, CXCL12, FOS, ß-defensin/LAP). Moreover, the protein expression of NOD1, p-IκBα, p-NF-κB/p-p65, p-ERK1/2, p-JNK, p-p38, and HDAC3 was significantly downregulated in the HC+SB group. In conclusion, iE-DAP-induced inflammation and liver disruption generated by the HC diet was mitigated by SB treatment.