Optimal dosing time of Dachengqi decoction for protection of extrapancreatic organs in rats with experimental acute pancreatitis

Genetic and pharmacological targeting of HINT2 promotes OXPHOS to alleviate inflammatory responses and cell necrosis in acute pancreatitis

The necrosis of pancreatic acinar cells is a key molecular event in the progression of acute pancreatitis (AP), with disturbances in mitochondrial energy metabolism considered to be a direct causative factor of acinar cell necrosis. Histidine triad nucleotide-binding protein 2 (HINT2) has been implicated in the development of various diseases, whereas its involvement in the progression of AP remains unclear. This study aims to investigate the role of HINT2 in AP. HINT2 expression in pancreatic tissues was significantly downregulated after AP. The results of glutathione-S-transferase (GST) pull-down and proteomics analyses revealed the involvement of HINT2 in regulating mitochondrial oxidative phosphorylation (OXPHOS) in AP mice. Moreover, lentivirus-mediated HINT2 overexpression not only alleviated AP-induced ATP depletion, but also relieved inflammatory responses and cell necrosis. Mechanistically, HINT2 interacted with cytochrome C oxidase II (MTCO2) to promote mitochondrial OXPHOS, thereby reducing ROS accumulation and inhibiting the activation of inflammatory signaling pathway. Besides, HINT2 act as a direct pharmacological target of Emo to elicit protective effects on AP. Importantly, Emo upregulates the expression of HINT2 and OXPHOS complex proteins and enhances the interaction between HINT2 and MTCO2. Furthermore, CRISPR/Cas9-mediated HINT2 knockout significantly impaired the protective effects of Emo against AP-induced mitochondrial energy metabolism disorders, inflammatory responses, and acinar cell necrosis. Overall, these results uncover a previously unexplored role for HINT2 in maintaining mitochondrial energy metabolism in pancreatic acinar cells and reveals novel mechanism and target for Emo-mediated AP remission.

Analysing pharmacodynamic interactions of traditional Chinese medicine in treating acute pancreatitis based on OPLS method

Acute pancreatitis (AP) is a surgical abdominal disease for which the Dachengqi Decoction (DCQD) of traditional Chinese medicine (TCM) is widely used in China. This study aims to analyse the pharmacodynamic interactions and quantitative relationship of DCQD in the treatment of AP based on orthogonal partial least squares (OPLS) analysis. The experimental data show organic chemical components as candidate pharmacodynamic substances (PS) in the blood and include pharmacodynamic indicators (PIs). Taking each PI as the target and using OPLS method to construct three types of mathematical equations, including the mathematical relationship between the pharmacodynamic substances and each target pharmacodynamic indicator (PS-TPI); the mathematical relationship between the pharmacodynamic substances, the pharmacodynamics indicators and each target pharmacodynamic indicator (PS, PI-TPI); and the mathematical relationship between the pharmacodynamic indicators and each target pharmacodynamic indicator (PI-TPI). Through analysis, we find that the R2Y(cum) values and VIP values indicate that PS and PI are the follow-up factors of TPI; the coefficient value indicates that there is a quantitative relationship between the PS and the TPI; and there also is a quantitative relationship between PI and TPI. The results demonstrated that PS and other PIs are the important influencing factors of TPI, and that there are interactions and quantitative relationships among the PIs.

Dao-Chi Powder Ameliorates Pancreatitis-Induced Intestinal and Cardiac Injuries via Regulating the Nrf2-HO-1-HMGB1 Signaling Pathway in Rats

Dao-Chi powder (DCP) has been widely used in the treatment of inflammatory diseases in the clinical practice of traditional Chinese medicine, but has not been used in acute pancreatitis (AP). This study aimed to evaluate the effect of DCP on severe AP (SAP) and SAP-associated intestinal and cardiac injuries. To this end, an SAP animal model was established by retrograde injection of 3.5% taurocholic acid sodium salt into the biliopancreatic ducts of rats. Intragastric DCP (9.6 g/kg.BW) was administered 12 h after modeling. The pancreas, duodenum, colon, heart and blood samples were collected 36 h after the operation for histological and biochemical detection. The tissue distributions of the DCP components were determined and compared between the sham and the SAP groups. Moreover, molecular docking analysis was employed to investigate the interactions between the potential active components of DCP and its targets (Nrf2, HO-1, and HMGB1). Consequently, DCP treatment decreased the serum levels of amylase and the markers of gastrointestinal and cardiac injury, further alleviating the pathological damage in the pancreas, duodenum, colon, and heart of rats with SAP. Mechanistically, DCP rebalanced the pro-/anti-inflammatory cytokines and inhibited MPO activity and MDA levels in these tissues. Furthermore, Western blot and RT-PCR results showed that DCP intervention enhanced the expression of Nrf2 and HO-1 in the duodenum and colon of rats with SAP, while inhibiting the expression of HMGB1 in the duodenum and heart. HPLC-MS/MS analysis revealed that SAP promoted the distribution of ajugol and oleanolic acid to the duodenum, whereas it inhibited the distribution of liquiritigenin to the heart and ajugol to the colon. Molecular docking analysis confirmed that the six screened components of DCP had relatively good binding affinity with Nrf2, HO-1, and HMGB1. Among these, oleanolic acid had the highest affinity for HO-1. Altogether, DCP could alleviated SAP-induced intestinal and cardiac injuries via inhibiting the inflammatory responses and oxidative stress partially through regulating the Nrf2/HO-1/HMGB1 signaling pathway, thereby providing additional supportive evidence for the clinical treatment of SAP.

Significant Succession of Intestinal Bacterial Community and Function During the Initial 72 Hours of Acute Pancreatitis in Rats

Acute pancreatitis (AP) is followed by structural and functional changes in the intestine, resulting from microbiome dysbiosis. However, it remains unclear how gut microbiome changes within the initial 72h of onset. In this study, severe acute pancreatitis (SAP), mild acute pancreatitis (MAP), and sham operation (SO) were replicated in rat models. 16S ribosomal RNA gene sequencing was used to explore the gut bacteria community. The predicted Cluster of Orthologous Genes (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways were associated with the 16S rRNA profiles. Compared to the SO group, significant community succession was found during the initial 72h in AP group. At 72 h after AP induction, the Firmicutes/Bacteroidetes (F/B) ratios were significantly different, with the highest ratio in SAP group and the lowest in MAP group. Lactobacillus was the most abundant genus, but it nearly disappeared in SAP rats at 72 h. Clostridiaceae 1 and Clostridium sensu stricto 1 were significantly enriched in AP group. Bacteroidales S24-7 and Bacteroidales S24-7 group norank were enriched in MAP group, while Collinsella, Morganella, and Blautia were enriched in SAP group. Lactobacillus was significantly correlated with nine COGs. Nine COGs showed significant differences between AP group and SO group. Moreover, four COGs showed significant differences between the MAP and SAP groups. KEGG Level_3 pathways propanoate metabolism (Ko00640) in AP group was significantly higher than that in SO group. The aspartate‒ammonia ligase and four KEGG orthology terms of the AP group were lower than that in the SO group, respectively. All these results suggest that the intestinal bacterial community structure and function was changed during the initial 72h in AP rats. The intestinal F/B ratio and the relative abundance of Lactobacillus could be potential markers for early diagnosis of MAP and SAP. The genus Clostridium sensu stricto 1 was the most enriched genus in AP, and may be an important marker for AP.