MicroRNA MiR-27a-5p Alleviates the Cerulein-Induced Cell Apoptosis and Inflammatory Injury of AR42J Cells by Targeting Traf3 in Acute Pancreatitis

Circ_0011446 Regulates Intramuscular Adipocyte Differentiation in Goats via the miR-27a-5p/FAM49B Axis

Intramuscular fat (IMF), or marbling, is a critical indicator of goat meat quality. Non-coding RNAs play a key role in the formation and deposition of IMF in vertebrates by regulating genes involved in its synthesis, degradation, and transport. The competing endogenous RNA (ceRNA) hypothesis identifies circular RNAs (circRNAs) as natural "sponges" for microRNAs (miRNAs). However, the precise mechanisms of circRNAs in goat IMF remain poorly understood. In the current study, we utilized existing sequencing data to construct a ceRNA regulatory network associated with intramuscular adipogenesis and fat deposition in goats. Our goal was to elucidate the post-transcriptional regulatory mechanism of family with sequence similarity 49 member B (FAM49B). Functionally, FAM49B was found to inhibit the differentiation of intramuscular preadipocytes and to directly interact with miR-27a-5p. Mechanistically, dual-luciferase reporter assays and quantitative real-time PCR (qRT-PCR) confirmed the interaction between circ0011446 and miR-27a-5p. Circ0011446 enhanced the expression of FAM49B mRNA and protein through post-transcriptional regulation. As a ceRNA, circ0011446 competitively binds miR-27a-5p, preventing miR-27a-5p from degrading FAM49B. In conclusion, our findings demonstrate that circ0011446 suppresses goat adipogenic differentiation of intramuscular preadipocytes by regulating the expression of the downstream target gene FAM49B through miR-27a-5p sequestration. This study provides a reference for goat meat quality or livestock breeding.

Exosomal miR-27a-5p attenuates inflammation through Toll-like receptor 7 in foodborne Salmonella infections

Salmonella is a common food-borne pathogen that is highly pathogenic and infectious, causing serious harm to livestock breeding and food safety. Uncovering the mechanisms of Salmonella infection and immune evasion can effectively prevent Salmonella contamination of livestock and poultry food. Here, small RNA sequencing results showed that exosomes produced by naïve murine macrophages RAW 264.7 cells contained a unique enrichment of a set of microRNAs (miRNAs) after Salmonella infection. Quantitative real-time polymerase chain reaction (qPCR) analysis verified that the tested miRNA (i.e. miR-27a-5p, miR-92a-1-5p and miR-1249-5p) showed similar expression patterns, consistent with small RNA sequencing data. TargetScan database predicted that the most promising targets for the differentially expressed miRNAs were abundant in the immune system, infectious diseases, and signal transduction pathways. Dual-luciferase reporter assays confirmed that Toll-like receptor 7 (TLR7) was the target of miR-27a-5p. Western blotting and enzyme-linked immunosorbent assay (ELISA) results revealed that overexpression of miR-27a-5p suppressed inflammation by targeting TLR7/nuclear factor kappa-B (NF-κB) signaling pathway and leading interleukin-6 (IL-6) and IL-1β cytokines slightly reduction in recipient macrophages, suggesting that exosomal miR-27a-5p uptake by naïve macrophages may inhibit pro-inflammatory macrophage differentiation. Therefore, these results contribute to our systematic understanding of the mechanism of exosomal miRNA in Salmonella infection, providing a potential target for preventing immune escape from Salmonella.

Visceral Adipocyte-Derived Extracellular Vesicle miR-27a-5p Elicits Glucose Intolerance by Inhibiting Pancreatic β-Cell Insulin Secretion

Pancreatic β-cell dysfunction caused by obesity can be associated with alterations in the levels of miRNAs. However, the role of miRNAs in such processes remains elusive. Here, we show that pancreatic islet miR-27a-5p, which is markedly increased in obese mice and impairs insulin secretion, is mainly delivered by visceral adipocyte-derived extracellular vesicles (EVs). Depleting miR-27a-5p significantly improved insulin secretion and glucose intolerance in db/db mice. Supporting the function of EV miR-27a-5p as a key pathogenic factor, intravenous injection of miR-27a-5p-containing EVs showed their distribution in mouse pancreatic islets. Tracing the injected adeno-associated virus (AAV)-miR-27a-5p (AAV-miR-27a) or AAV-FABP4-miR-27a-5p (AAV-FABP4-miR-27a) in visceral fat resulted in upregulating miR-27a-5p in EVs and serum and elicited mouse pancreatic β-cell dysfunction. Mechanistically, miR-27a-5p directly targeted L-type Ca2+ channel subtype CaV1.2 (Cacna1c) and reduced insulin secretion in β-cells. Overexpressing mouse CaV1.2 largely abolished the insulin secretion injury induced by miR-27a-5p. These findings reveal a causative role of EV miR-27a-5p in visceral adipocyte-mediated pancreatic β-cell dysfunction in obesity-associated type 2 diabetes mellitus.

ARTICLE HIGHLIGHTS

Lonicerin protects pancreatic acinar cells from caerulein-induced apoptosis, inflammation, and ferroptosis by activating the SIRT1/GPX4 signaling pathway

Acute pancreatitis (AP) is a familiar emergency of digestive system characterized by pancreatic inflammation. Lonicerin (LCR) has been reported to exert anti-inflammatory and immunomodulatory characteristics in several inflammatory diseases. Nevertheless, its role and mechanism involved in AP are still unknown. This study was designed to explore the protective effect and potential mechanism of LCR in AP. In this study, LCR and ferrostatin-1 alleviated, but erastin aggravated caerulein (CAE) exposure-induced cytotoxicity and reduction of cell viability in AR42J cells. LCR exhibited a protective role in CAE-treated AR42J cells, as evidenced by alleviation of apoptosis, inflammation, and ferroptosis. Mechanistically, LCR decreased the phosphorylation level of nuclear factor-kappa B p65 and increased the levels of silent information regulator 1 (SIRT1) and glutathione peroxidase 4 (GPX4) in CAE-treated AR42J cells. Furthermore, functional rescue experiments manifested that knockdown of SIRT1 partially negated the inhibitory action of LCR against CAE-induced apoptosis, inflammation, and ferroptosis in AR42J cells. Overall, LCR mitigates apoptosis, inflammation, and ferroptosis in CAE-exposed AR42J cells, which is related to the activation of the SIRT1/GPX4 signaling pathway.

MALAT1: A key regulator in lung cancer pathogenesis and therapeutic targeting

Lung cancer remains a formidable global health burden, necessitating a comprehensive understanding of the underlying molecular mechanisms driving its progression. Recently, lncRNAs have become necessary controllers of various biological functions, including cancer development. MALAT1 has garnered significant attention due to its multifaceted role in lung cancer progression. Lung cancer, among other malignancies, upregulates MALAT1. Its overexpression has been associated with aggressive tumor behavior and poor patient prognosis. MALAT1 promotes cellular proliferation, epithelial-mesenchymal transition (EMT), and angiogenesis in lung cancer, collectively facilitating tumor growth and metastasis. Additionally, MALAT1 enhances cancer cell invasion by interacting with numerous signaling pathways. Furthermore, MALAT1 has been implicated in mediating drug resistance in lung cancer, contributing to the limited efficacy of conventional therapies. Recent advancements in molecular biology and high-throughput sequencing technologies have offered fresh perspectives into the regulatory networks of MALAT1 in lung cancer. It exerts its oncogenic effects by acting as a ceRNA to sponge microRNAs, thereby relieving their inhibitory effects on target genes. Moreover, MALAT1 also influences chromatin remodeling and post-translational modifications to modulate gene expression, further expanding its regulatory capabilities. This review sheds light on the multifaceted roles of MALAT1 in lung cancer progression, underscoring its potential as an innovative therapeutic target and diagnostic biomarker. Targeting MALAT1 alone or combined with existing therapies holds promise to mitigate lung cancer progression and improve patient outcomes.

miR-455-3p ameliorates pancreatic acinar cell injury by targeting Slc2a1

Objective

With the number of patients with acute pancreatitis (AP) increasing year by year, it is pressing to explore new key genes and markers for the treatment of AP. miR-455-3p/solute carrier family 2 member 1 (Slc2a1) obtained through bioinformatics analysis may participate in the progression of AP.

Materials and Methods

The C57BL/6 mouse model of AP was constructed for subsequent studies. Through bioinformatics analysis, the differentially expressed genes related to AP were screened and hub genes were identified. A caerulein-induced AP animal model was constructed to detect the pathological changes of mouse pancreas by HE staining. The concentrations of amylase and lipase were measured. Primary mouse pancreatic acinar cells were isolated and subjected to microscopy to observe their morphology. The enzymatic activities of trypsin and amylase were detected. The secretion of inflammatory cytokines in mouse were measured with the ELISA kits of TNF-α, IL-6 and IL-1β to determine pancreatic acinar cell damage. A binding site between the Slc2a1 3' UTR region and the miR-455-3p sequence was verified by dual-luciferase reporter assay. The expression of miR-455-3p was quantified by qRT-PCR, and Slc2a1 were detected by western blot.

Results

A total of five (Fyn, Gadd45a, Sdc1, Slc2a1, and Src) were identified by bioinformatics analysis, and miR-455-3p/Slc2a1 were further studied. HE staining results showed that the AP models were successfully established by caerulein induction. In mice with AP, the expression of miR-455-3p was reduced, while that of Slc2a1 was increased. In the caerulein-induced cell model, the expression of Slc2a1 was significantly reduced after intervention of miR-455-3p mimics, whereas increased after miR-455-3p inhibitor treatment. miR-455-3p decreased the secretion of inflammatory cytokines in the cell supernatant, reduced the activity of trypsin and amylase, and alleviated the cell damage induced by caerulein. In addition, Slc2a1 3'UTR region was bound by miR-455-3p, and its protein expression was also regulated.

Conclusion

miR-455-3p alleviated caerulein-induced mouse pancreatic acinar cell damage by regulating the expression of Slc2a1.

Total flavonoids of Chrysanthemum indicum L inhibit acute pancreatitis through suppressing apoptosis and inflammation

Acute pancreatitis (AP) is one of the most common acute abdomen. Inflammation and apoptosis are closely linked with AP development. Total flavonoids of Chrysanthemum indicum L (TFC) has been proved to inhibit inflammation and apoptosis. If TFC could suppress AP remains unclear. AP animal and cell models were established with Cerulein. The pancreatic tissue injury was measured with HE staining. Inflammatory factors were detected with ELISA method. The protein expression was evaluated with Western blotting. Inhibition of AP in vivo was achieved by TFC by inhibiting serum amylase, myeloperoxidase (MPO), and water content of pancreatic tissue. The increased inflammatory response and activation of NF-κB signaling pathway in AP rats were inhibited after TFC treatment. The activation of NF-κB signaling pathway, increase of cell apoptosis and inflammatory factors in AR42J cells were suppressed by TFC. We demonstrated that TFC could significantly inhibit AP through restraining serum amylase, MPO, water content of pancreatic tissue, inflammation levels, apoptosis, and NF-κB signaling pathway activation. This study might clarify the potential inhibition mechanism of TFC in AP development.

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.

Liver transcriptomics reveals microRNA features of the host response in a mouse model of dengue virus infection

BACKGROUND

Organ dysfunction, especially liver injury, caused by dengue virus (DENV) infection has been associated with fatal cases in dengue patients around the world. However, the pathophysiological mechanisms of liver involvement in dengue remain unclear. There is accumulating evidence that miRNAs are playing an important role in regulating viral pathogenesis, and it can help in diagnostic and anti-viral therapies development.

METHODS

We collected liver tissues of DENV-infected for small RNA sequencing to identify significantly different express miRNAs during dengue virus infection, and the identified target genes of these miRNAs were annotated by biological function and pathway enrichment.

RESULTS

31 significantly altered miRNAs were identified, including 16 up-regulated and 15 down-regulated miRNAs. By performing a series of miRNA prediction and signaling pathway enrichment analyses, the down-regulated miRNAs of mmu-miR-484, mmu-miR-1247-5p and mmu-miR-6538 were identified to be the crucial miRNAs. Further analysis revealed that the inflammation and immune responses involving Hippo, PI3K-Akt, MAPK, Wnt, mTOR, TGF-beta, Tight junction, and Platelet activation were modulated collectively by these three key miRNAs during DENV infection. These pathways are considered to be closely associated with the pathogenic mechanism and treatment strategy of dengue patients.

CONCLUSION

The miRNAs identified by sequencing, especially miR-484 may be the potential therapeutic targets for liver involvement in dengue patients which involves the regulation of vascular permeability and expression of inflammatory cytokines.

Fighting Fire with Fire: Exosomes and Acute Pancreatitis-Associated Acute Lung Injury

Acute pancreatitis (AP) is a prevalent clinical condition of the digestive system, with a growing frequency each year. Approximately 20% of patients suffer from severe acute pancreatitis (SAP) with local consequences and multi-organ failure, putting a significant strain on patients' health insurance. According to reports, the lungs are particularly susceptible to SAP. Acute respiratory distress syndrome, a severe type of acute lung injury (ALI), is the primary cause of mortality among AP patients. Controlling the mortality associated with SAP requires an understanding of the etiology of AP-associated ALI, the discovery of biomarkers for the early detection of ALI, and the identification of potentially effective drug treatments. Exosomes are a class of extracellular vesicles with a diameter of 30-150 nm that are actively released into tissue fluids to mediate biological functions. Exosomes are laden with bioactive cargo, such as lipids, proteins, DNA, and RNA. During the initial stages of AP, acinar cell-derived exosomes suppress forkhead box protein O1 expression, resulting in M1 macrophage polarization. Similarly, macrophage-derived exosomes activate inflammatory pathways within endothelium or epithelial cells, promoting an inflammatory cascade response. On the other hand, a part of exosome cargo performs tissue repair and anti-inflammatory actions and inhibits the cytokine storm during AP. Other reviews have detailed the function of exosomes in the development of AP, chronic pancreatitis, and autoimmune pancreatitis. The discoveries involving exosomes at the intersection of AP and acute lung injury (ALI) are reviewed here. Furthermore, we discuss the therapeutic potential of exosomes in AP and associated ALI. With the continuous improvement of technological tools, the research on exosomes has gradually shifted from basic to clinical applications. Several exosome-specific non-coding RNAs and proteins can be used as novel molecular markers to assist in the diagnosis and prognosis of AP and associated ALI.

Downregulation of lncRNA NEAT1 Relieves Caerulein-Induced Cell Apoptosis and Inflammatory Injury in AR42J Cells Through Sponging miR-365a-3p in Acute Pancreatitis

Mounting evidence suggests that long non-coding RNAs (lncRNAs) and microRNAs exert a critical regulatory role in acute pancreatitis. The present study aimed to explore the role of lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in acute pancreatitis (AP) that was induced by caerulein in rat pancreatic acinar cells (AR42J). The potential target sites of lncRNA NEAT1 and miR-365a-3p were predicted using starBase and were confirmed using dual-luciferase reporter assay. Reverse transcription-quantitative polymerase chain reaction was performed to assess lncRNA NEAT1 and miR-365a-3p expression levels in AP induced by caerulein. Cell Counting Kit-8 and flow cytometry assays were performed to assess AR42J cell viability. Western blotting was performed to evaluate the expression of apoptosis-related proteins. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels were detected by ELISA. The results of the dual-luciferase reporter assay confirmed that miR-365a-3p could bind to NEAT1. LncRNA NEAT1 was upregulated in AR42J cells treated with 10 nmol/l caerulein, and miR-365a-3p was expressed at low levels in an AP model. Overexpression of miR-365a-3p suppressed the apoptosis and inflammatory response of AR42J cells induced by caerulein. Importantly, inhibition of lncRNA NEAT1 decreased apoptosis and inflammation in caerulein-treated AR42J cells, while these effects were reverted upon co-transfection with a miR-365a-3p inhibitor. In conclusion, lncRNA NEAT1 was involved in AP progression by sponging miR-365a-3p and may thus be a novel target for treating patients with AP.

MiR-27a-5p regulates acrylamide-induced mitochondrial dysfunction and intrinsic apoptosis via targeting Btf3 in rats

Acrylamide (AA), a potential carcinogen, is commonly formed in foods rich in carbohydrates at high heat. It is known that AA-induced mitochondrial dysfunction is responsible for its toxicity. Previously we found AA exposure increased miR-27a-5p expression in livers of SD rats. Here, the regulation mechanism of miR-27a-5p in mitochondrial dysfunction was investigated in rat liver cell lines (IAR20) and SD rats. The results showed that the overexpressed miR-27a-5p contributes to modulating mitochondrial dysfunction and Btf3 is identified as its target gene. The knockdown of Btf3 increases the cleaved PARP1 level and the phosphorylation of ATM and p53, which results in mitochondria-dependent apoptosis. Therefore, the miR-27a-5p-Btf3-ATM-p53 axis might play a vital role in the promotion of AA-induced cell apoptosis through disrupting mitochondrial structure and function. This would provide a potential target for the assessment and intervention of AA toxicity.

Interfering hsa_circ_0073748 alleviates caerulein-induced ductal cell injury in acute pancreatitis by inhibiting miR-132-3p/TRAF3/NF-κB pathway

Circular RNA hsa_circ_0073748 (circ_0073748) is upregulated in patients with acute pancreatitis (AP), a clinically common sudden inflammatory response. MicroRNA (miR)-132-3p is a stress-induced factor with high conservation between species. Herein, expression and role of circ_0073748 and miR-132-3p in caerulein-induced pancreatitis were studied. Expression levels of circ_0073748, miR-132-3p, TNF receptor associated factor 3 (TRAF3), Bcl-2 and Bcl-2-associated X protein (Bax) were examined by reverse transcription-quantitative PCR and Western blotting. Cell proliferation was measured by MTS and EdU assays. Flow cytometry and assay kits detected apoptosis, inflammatory, and oxidative responses. Western blotting detected nuclear factor (NF)-κB signaling pathway. Circ_0073748 was upregulated and miR-132-3p was downregulated in AP patients' plasma and human pancreatic ductal HPDE6-C7 cells with caerulein induction. Interfering circ_0073748 and reinforcing miR-132-3p improved cell viability, EdU incorporation, and superoxide dismutase (SOD) activity of caerulein-treated HPDE6-C7 cells but suppressed malonaldehyde (MDA), IL-6 and TNF-α levels and apoptosis rate. Moreover, TRAF3 downregulation was allied with circ_0073748 silencing and miR-132-3p overexpression in caerulein-induced HPDE6-C7 cells. Mechanically, circ_0073748 was identified as a sponge for miR-132-3p to modulate TRAF3 expression, thus establishing a competitive endogenous RNA (ceRNA) regulation model. Notably, circ_0073748 blockage could suppress expressions of phosphorylated P65 (p-P65) and p-IκB in caerulein-induced HPDE6-C7 cells by promoting miR-132-3p and inhibiting TRAF3. Silencing circ_0073748 and upregulating miR-132-3p could alleviate caerulein-induced HPDE6-C7 injury and inactivate canonical NF-κB signal by inhibiting TRAF3. Circ_0073748/miR-132-3p/TRAF3 ceRNA pathway might be one underlying mechanism and therapeutic target of caerulein-induced AP.

Protective Effect of miR-193a-5p and miR-320-5p on Caerulein-Induced Injury in AR42J Cells

BACKGROUND

Acute pancreatitis is a common inflammatory disease. MicroRNAs have been implicated in the pathogenesis of acute pancreatitis.

AIMS

The purpose of this study was to investigate the precise roles of miR-193a-5p and miR-320-5p in AP.

METHODS

The levels of miR-193a-5p, miR-320-5p and tumor necrosis factor receptor-associated factor 3 were detected by quantitative real-time polymerase chain reaction. Cell apoptosis was determined using flow cytometry. Enzyme-linked immunosorbent assay was performed to measure TNF-α, IL-6, IL-1β and IL-8 production, amylase activity, and malondialdehyde content. Targeted relationship between miR-193a-5p or miR-320-5p and TRAF3 was confirmed by the dual-luciferase reporter and RNA immunoprecipitation assays.

RESULTS

Our data showed that miR-193a-5p and miR-320-5p were down-regulated in acute pancreatitis serum and caerulein-treated AR42J cells. The increased expression of miR-193a-5p or miR-320-5p alleviated caerulein-induced cell injury in AR42J cells. Tumor necrosis factor receptor-associated factor 3 was a direct target of miR-193a-5p and miR-320-5p in AR42J cells. Moreover, miR-193a-5p and miR-320-5p regulated caerulein-induced AR42J cells injury through targeting tumor necrosis factor receptor-associated factor 3.

CONCLUSION

The present findings demonstrated that miR-193a-5p and miR-320-5p protected AR42J cells against caerulein-induced cell injury by targeting tumor necrosis factor receptor-associated factor 3, highlighting their roles as potential therapeutic targets for acute pancreatitis treatment.