Circ_UTRN ameliorates caerulein-induced acute pancreatitis in vitro via reducing inflammation and promoting apoptosis through miR-320-3p/PTK2 axis

Involvement of circ_0029407 in Caerulein-Evoked Cytotoxicity in Human Pancreatic Cells via the miR-579-3p/TLR4/NF-κB Pathway

Acute pancreatitis (AP) is the most prevalent gastrointestinal inflammatory disease. Circular RNAs (circRNAs) are implicated in the development of AP. Here, we identified the precise action of circ_0029407 in AP development. Human pancreatic epithelial cells (HPECs) were stimulated with caerulein. Cell viability, proliferation, and apoptosis were gauged by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and flow cytometry assays, respectively. Circ_0029407, microRNA (miR)-579-3p, and toll-like receptor 4 (TLR4) were quantified by a qRT-PCR or western blot assay. Dual-luciferase reporter and RNA pull-down assays were performed to evaluate the direct relationship between miR-579-3p and circ_0029407 or TLR4. Our results indicated that circ_0029407 was markedly overexpressed in AP serum samples and caerulein-stimulated HPECs. Reduction of circ_0029407 attenuated caerulein-imposed HPEC damage by promoting cell proliferation and repressing cell apoptosis and inflammation. Mechanistically, circ_0029407 contained a miR-579-3p binding site, and miR-579-3p downregulation reversed the effect of circ_0029407 reduction on caerulein-imposed HPEC damage. TLR4 was identified as a direct and functional target of miR-579-3p, and TLR4 overexpression reversed the impact of miR-579-3p upregulation on attenuating caerulein-imposed HPEC damage. Moreover, circ_0029407 regulated the TLR4/nuclear factor NF-kappaB (NF-κB) signaling by acting as a competing endogenous RNA (ceRNA) for miR-579-3p. Our study suggests that circ_0029407 regulates caerulein-imposed cell injury in human pancreatic cells at least in part via the TLR4/NF-κB signaling pathway by functioning as a ceRNA for miR-579-3p.

circ_UTRN inhibits ferroptosis of ARJ21 cells to attenuate acute pancreatitis progression by regulating the miR-760-3p/FOXO1/GPX4 axis

Aim

To explore the function of circ_UTRN in acute pancreatitis (AP).

Methods

After exposing AR42J cells to caerulein, the levels of circ_UTRN, miR-760-3p, and glutathione peroxidase 4 (GPX4) were determined by quantitative polymerase chain reaction. Additionally, GPX4 and forkhead box O1 (FOXO1) protein levels were assessed by western blot. The levels of oxidative stress and ferroptosis in the supernatant of the treated AR42J cells were also assessed using commercial kits.

Results

circ_UTRN inhibited caerulein-induced oxidative stress and ferroptosis by binding with miR-760-3p. Additionally, miR-760-3p directly targeted FOXO1, thereby regulating GPX4 levels. Furthermore, GPX4 knockdown abolished the effect of miR-760-3p downregulation in AP.

Conclusion

circ_UTRN inhibited oxidative stress and ferroptosis by regulating the miR-760-3p/FOXO1/GPX4 axis. This is a potential new treatment strategy for AP.

miRNA transcriptomics analysis shows miR-483-5p and miR-503-5p targeted miRNA in extracellular vesicles from severe acute pancreatitis-associated lung injury patients

AIM

This study sought to identify potential biomarkers and miRNA-mRNA networks within extracellular vesicles (EVs) for detecting severe acute pancreatitis-associated lung injury (SAPALI).

METHODS

Blood-derived EVs were isolated, and their miRNA transcriptomic profiles were comprehensively analyzed using miRBase v.21 database along with miRDeep2 tool to predict novel miRNAs. DEGseq R package was deployed for the identification of differentially expressed miRNAs (DEMs). Protein-protein interaction (PPI) networks were assembled using STRING and Cytoscape. A lung injury model was established using Lipopolysaccharide (LPS)-induced BEAS-2B cells, chosen for their respiratory epithelial origin and pertinent association with lung injury. The expression levels of targeted miRNA and associated proteins, TLR4, NF-κB mRNA were quantified via RT-PCR and Western Blot. Levels of IL-6, IL-1β, TNF-α, and ROS were measured using designated kits. Dual-luciferase reporter assay was conducted to examine the interaction between miRNA and proteins.

RESULTS

The comparisons between the SAPALI and the control group revealed 10 DEM, including miR-503-5p and miR-483-5p. The cytoHubba plugin in Cytoscape identified three principal miRNA-mRNA interactions: miR-483-5p with PTK2 and HDAC2; miR-28-5p with MAPK1, TP53BP1, SEMA3A; and miR-503-5p with PPP1CB, SEMA6D, EPHB2, UNC5B. The SAPALI model exhibited elevated miR-503-5p, HDAC2 and inflammatory markers, with a decline UNC5B, miR-483-5p and miR-28-5p. Transfection with miR-503-5p and miR-483-5p inhibitors increased the levels of their supposed binding proteins but not miR-28-5p inhibitor. The Dual-luciferase reporter gene assay identified the interaction of miR-503-5p with UNC5B, and miR-483-5p with HDAC2, but not miR-28-5p with TP53BP1.

CONCLUSIONS

Our study maps miRNA-mRNA interactions in SAPALI, identifying miR-503-5p and miR-483-5p as critical regulatory miRNAs.

The Role of MicroRNAs in Pancreatitis Development and Progression

Pancreatitis (acute and chronic) is an inflammatory disease associated with significant morbidity, including a high rate of hospitalization and mortality. MicroRNAs (miRs) are essential post-transcriptional modulators of gene expression. They are crucial in many diseases' development and progression. Recent studies have demonstrated aberrant miRs expression patterns in pancreatic tissues obtained from patients experiencing acute and chronic pancreatitis compared to tissues from unaffected individuals. Increasing evidence showed that miRs regulate multiple aspects of pancreatic acinar biology, such as autophagy, mitophagy, and migration, impact local and systemic inflammation and, thus, are involved in the disease development and progression. Notably, multiple miRs act on pancreatic acinar cells and regulate the transduction of signals between pancreatic acinar cells, pancreatic stellate cells, and immune cells, and provide a complex interaction network between these cells. Importantly, recent studies from various animal models and patients' data combined with advanced detection techniques support their importance in diagnosing and treating pancreatitis. In this review, we plan to provide an up-to-date summary of the role of miRs in the development and progression of pancreatitis.

Enhancing or inhibiting apoptosis? The effects of ucMSC-Ex in the treatment of different degrees of traumatic pancreatitis

The animal models of traumatic pancreatitis (TP) were established to evaluate the specific mechanisms by which umbilical cord mesenchymal stem cell-derived exosomes (ucMSC-Ex) exert therapeutic effects. Sixty four rats were randomly divided into eight groups, including TP groups with three different degrees and relevant groups with ucMSC-Ex treated. The degrees of pancreatic tissue injury were evaluated by Histological Examination. Furthermore, enzyme-linked immunosorbent assay were applied to evaluate the activity of pancreatic enzymes and levels of inflammatory factors in serum. Finally, the apoptotic effects of each group were evaluated by TUNEL, western blot (WB), and real time fluorescence quantitative polymerase chain reaction (RT-qPCR). The pancreatic histopathological score and serum amylase and lipase levels gradually increased in various degrees of TP and the levels in the treatment group were all significantly decreased. The apoptosis index gradually increased in each TP group and significantly decreased in the treatment group in TUNEL results. WB and RT-qPCR showed the same trend, that bax and caspase-3 gradually increased and bcl-2 gradually decreased in TP groups. Compared with TP groups, the expression of bax and caspase-3 were lower while bcl-2 expression was higher in the treatment group. ucMSC-Ex suppressed the inflammatory response and inhibited pancreatic acinar cell apoptosis to promote repair of injured pancreatic tissue.

Sinapic Acid Alleviates Acute Pancreatitis in Association with Attenuation of Inflammation, Pyroptosis, and the AMPK/NF-κB Signaling Pathway

Among the diseases of the digestive system, the incidence of acute pancreatitis (AP) has increased. Although the AP is primarily self-limited, mortality remains high when it progressed to severe acute pancreatitis (SAP). Despite significant advances in new drug development, treatments for AP are not ideal. Here, we discovered a novel hydroxycinnamic acid, sinapic acid (SA), which is widely distributed in plants and is an effective treatment for AP. Using in vitro and in vivo models, we demonstrated that pretreatment with SA ameliorated cerulein-induced pancreatic damage and inflammation and inhibited the activation of Caspase-1 and Caspase-11, which mediate pyroptosis of pancreatic acinar cells during AP. These effects may occur through the inhibition of AMPK phosphorylation and downregulation of NF-[Formula: see text]B. Our findings demonstrate the therapeutic effects and reveal the underlying mechanisms of SA, which warrants its further study as an effective treatment for AP.