A microRNA checkpoint for Ca2+ signaling and overload in acute pancreatitis

Oxidative stress and acute pancreatitis (Review)

Acute pancreatitis (AP) is a common inflammatory disorder of the exocrine pancreas that causes severe morbidity and mortality. Although the pathophysiology of AP is poorly understood, a substantial body of evidence suggests some critical events for this disease, such as dysregulation of digestive enzyme production, cytoplasmic vacuolization, acinar cell death, edema formation, and inflammatory cell infiltration into the pancreas. Oxidative stress plays a role in the acute inflammatory response. The present review clarified the role of oxidative stress in the occurrence and development of AP by introducing oxidative stress to disrupt cellular Ca2+ balance and stimulating transcription factor activation and excessive release of inflammatory mediators for the application of antioxidant adjuvant therapy in the treatment of AP.

Distribution of TRPC3 and TRPC6 in the human exocrine and endocrine pancreas

BACKGROUND

Expression and function of TRPC3 and TRPC6 in the pancreas is a controversial topic. Investigation in human tissue is seldom. We aimed to provide here a detailed description of the distribution of TRPC3 and TRPC6 in the human exocrine and endocrine pancreas.

METHODS

We collected healthy samples from cadavers (n = 4) and visceral surgery (n = 4) to investigate the respective expression profiles using immunohistochemical tracing with knockout-validated antibodies.

RESULTS

TRPC3- and TRPC6-proteins were detected in different pancreatic structures including acinar cells, as well as epithelial ductal cells from intercalate, intralobular, and interlobular ducts. Respective connective tissue layers appeared unstained. Endocrine islets of Langerhans were clearly and homogenously immunolabeled by the anti-TRPC3 and anti-TRPC6 antibodies. Insular α, β, γ, and δ cells were conclusively stained, although no secure differentiation of cell types was performed.

CONCLUSIONS

Due to aforementioned antibody specificity verification, protein expression in the immunolabeled localizations can be accepted. Our study in human tissue supports previous investigations especially with respect to acinar and insular α and β cells, while other localizations are here reported for the first time to express TRPC3 and TRPC6, ultimately warranting further research.

Biomimetic Trypsin-Responsive Structure-Bridged Mesoporous Organosilica Nanomedicine for Precise Treatment of Acute Pancreatitis

Developing strategies to target injured pancreatic acinar cells (PACs) in conjunction with primary pathophysiology-specific pharmacological therapy presents a challenge in the management of acute pancreatitis (AP). We designed and synthesized a trypsin-cleavable organosilica precursor bridged by arginine-based amide bonds, leveraging trypsin's ability to selectively identify guanidino groups on arginine via Asp189 at the active S1 pocket and cleave the carboxy-terminal (C-terminal) amide bond via catalytic triads. The precursors were incorporated into the framework of mesoporous silica nanoparticles (MSNs) for encapsulating the membrane-permeable Ca2+ chelator BAPTA-AM with a high loading content (∼43.9%). Mesenchymal stem cell membrane coating and surface modification with PAC-targeting ligands endow MSNs with inflammation recruitment and precise PAC-targeting abilities, resulting in the highest distribution at 3 h in the pancreas with 4.7-fold more accumulation than that of naked MSNs. The outcomes transpired as follows: After bioinspired MSNs' skeleton biodegradation by prematurely and massively activated trypsin, BAPTA-AM was on-demand released in injured PACs, thereby effectively eliminating intracellular calcium overload (reduced Ca2+ level by 81.3%), restoring cellular redox status, blocking inflammatory cascades, and inhibiting cell necrosis by impeding the IκBα/NF-κB/TNF-α/IL-6 and CaMK-II/p-RIP3/p-MLKL/caspase-8,9 signaling pathways. In AP mice, a single dose of the formulation significantly restored pancreatic function (lipase and amylase reduced more by 60%) and improved the survival rate from 50 to 91.6%. The formulation offers a potentially effective strategy for clinical translation in AP treatment.

The role of mitochondrial damage-associated molecular patterns in acute pancreatitis

Acute pancreatitis (AP) is one of the most common gastrointestinal tract diseases with significant morbidity and mortality. Current treatments remain unspecific and supportive due to the severity and clinical course of AP, which can fluctuate rapidly and unpredictably. Mitochondria, cellular power plant to produce energy, are involved in a variety of physiological or pathological activities in human body. There is a growing evidence indicating that mitochondria damage-associated molecular patterns (mtDAMPs) play an important role in pathogenesis and progression of AP. With the pro-inflammatory properties, released mtDAMPs may damage pancreatic cells by binding with receptors, activating downstream molecules and releasing inflammatory factors. This review focuses on the possible interaction between AP and mtDAMPs, which include cytochrome c (Cyt c), mitochondrial transcription factor A (TFAM), mitochondrial DNA (mtDNA), cardiolipin (CL), adenosine triphosphate (ATP) and succinate, with focus on experimental research and potential therapeutic targets in clinical practice. Preventing or diminishing the release of mtDAMPs or targeting the mtDAMPs receptors might have a role in AP progression.

Three-Way Junction-Assisted Rolling Circle Amplification Integrated with trans-Cleavage of Cas12a for Sensitive and Reliable Detection of miRNA

MicroRNAs (miRNAs) serve a crucial role in numerous biological processes, such as acute pancreatitis development. Due to its low abundance and high similarity among homogeneous family members, sensitive and reliable detection of microRNA remains a formidable challenge. By combining the three-way junction-assisted rolling circle amplification (RCA) with the trans-cleavage of Cas12a, we propose a novel fluorescent technique for sensitive miRNA detection. In order to increase the amplification efficiency of RCA-based methods, catalytic hairpin amplification (CHA) is incorporated into the RCA process, playing the roles of specific target recognition and three-way junction formation. Consequently, the method demonstrated a six-orders-of-magnitude detection range and a LOD as low as 27 aM, making it a promising method for the early diagnosis of various diseases.

A Hierarchical Mechanotransduction System: From Macro to Micro

Mechanotransduction is a strictly regulated process whereby mechanical stimuli, including mechanical forces and properties, are sensed and translated into biochemical signals. Increasing data demonstrate that mechanotransduction is crucial for regulating macroscopic and microscopic dynamics and functionalities. However, the actions and mechanisms of mechanotransduction across multiple hierarchies, from molecules, subcellular structures, cells, tissues/organs, to the whole-body level, have not been yet comprehensively documented. Herein, the biological roles and operational mechanisms of mechanotransduction from macro to micro are revisited, with a focus on the orchestrations across diverse hierarchies. The implications, applications, and challenges of mechanotransduction in human diseases are also summarized and discussed. Together, this knowledge from a hierarchical perspective has the potential to refresh insights into mechanotransduction regulation and disease pathogenesis and therapy, and ultimately revolutionize the prevention, diagnosis, and treatment of human diseases.

Acute pancreatitis: pathogenesis and emerging therapies

Acute pancreatitis is a severe inflammatory disorder with limited treatment options. Improved understanding of disease mechanisms has led to new and potential therapies. Here we summarize what we view as some of the most promising new therapies for treating acute pancreatitis, emphasizing the rationale of specific treatments based on disease mechanisms. Targeted pharmacologic interventions are highlighted. We explore potential treatment benefits and risks concerning reducing acute injury, minimizing complications, and improving long-term outcomes. Mechanisms associated with acute pancreatitis initiation, perpetuation, and reconstitution are highlighted, along with potential therapeutic targets and how these relate to new treatments.

Discoveries of GPR39 as an evolutionarily conserved receptor for bile acids and of its involvement in biliary acute pancreatitis

Acute pancreatitis (AP) is one of the most common gastrointestinal diseases. Bile acids (BAs) were proposed to be a cause of AP nearly 170 years ago, though the underlying mechanisms remain unclear. Here, we report that two G protein-coupled receptors, GPR39 and GHSR, mediated cellular responses to BAs. Our results revealed GPR39 as an evolutionarily conserved receptor for BAs, particularly 3-O-sulfated lithocholic acids. In cultured cell lines, GPR39 is sufficient for BA-induced Ca2+ elevation. In pancreatic acinar cells, GPR39 mediated BA-induced Ca2+ elevation and necrosis. Furthermore, AP induced by BAs was significantly reduced in GPR39 knockout mice. Our findings provide in vitro and in vivo evidence demonstrating that GPR39 is necessary and sufficient to mediate BA signaling, highlighting its involvement in biliary AP pathogenesis, and suggesting it as a promising therapeutic target for biliary AP.

Multi-dimensional metabolomic profiling reveals dysregulated ornithine metabolism hallmarks associated with a severe acute pancreatitis phenotype

To reveal dysregulated metabolism hallmark that was associated with a severe acute pancreatitis (SAP) phenotype. In this study, LC-MS/MS-based targeted metabolomics was used to analyze plasma samples from 106 acute pancreatitis (AP) patients (34 mild, 38 moderate, and 34 severe) admitted within 48 hours from abdominal pain onset and 41 healthy controls. Temporal metabolic profiling was performed on days 1, 3, and 7 after admission. A random forest (RF) was performed to significantly determine metabolite differences between SAP and non-SAP (NSAP) groups. Mass spectrometry imaging (MSI) and immunohistochemistry were conducted for the examination of pancreatic metabolite and metabolic enzyme alterations, respectively, on necrosis and paracancerous tissues. Simultaneously determination of serum and pancreatic tissue metabolic alterations using an L-ornithine-induced AP model to discover metabolic commonalities. Twenty-two significant differential metabolites screened by RF were selected to build an accurate model for the prediction of SAP from NSAP (AUC = 0.955). Six of 22 markers were found by MSI with significant alterations in pancreatic lesions, reduced ornithine-related metabolites were also identified. The abnormally expressed arginase2 and ornithine transcarboxylase were further discovered in combination with time-course metabolic profiling in the SAP animal models, the decreased ornithine catabolites were found at a late stage of inflammation, but ornithine-associated metabolic enzymes were activated during the inflammatory process. The plasma metabolome of AP patients is distinctive, which shows promise for early SAP diagnosis. AP aggravation is linked to the activated ornithine metabolic pathway and its inadequate levels of catabolites in in-situ lesion.

MiRNA-26a-5p inhibits preterm labor initiation by targeting and regulating TRPC3 ion channel protein expression

The incidence of preterm birth (PTB) is increasing annually worldwide, leading to various health problems or even fetal deaths. Our previous work demonstrated the activation of transient receptor potential cation channel subfamily C 3 (TRPC3) in mice with PTB, and its activation could promote inward flow of calcium ions and uterine smooth muscle (USM) contraction via regulation of Cav3.2, Cav3.1, and Cav1.2. However, the upstream regulators of TRPC3 and its mechanisms remain unknown. In the present study, the binding of miR-26a-5p to the 3' untranslated region of TRPC3 was predicted by bioinformatics databases (TargetScanHuman and starBase v3.0) and confirmed by a dual-luciferase assay. MiR-26a-5p was downregulated, while TRPC3 was upregulated in the USM tissues of patients with PTB compared to people without PTB. The results showed that miR-26a-5p mimic transfection markedly reduced TRPC3 expression in LPS-stimulated USM cells. Additionally, miR-26a-5p regulated intracellular Ca2+ levels in USM cells by targeting TRPC3. Furthermore, miR-26a-5p inhibited the CPI17/PKC/PLCγ signaling pathway and reduced the expression of Cav3.2, Cav3.1, and Cav1.2. In conclusion, miR-26a-5p regulated the initiation of PTB by targeting TRPC3 and regulating intracellular Ca2+ levels. This study provides a promising diagnostic biomarker and therapeutic target for PTB.

Extrachromosomal circular MiR-17-92 amplicon promotes HCC

BACKGROUND AND AIMS

Extrachromosomal circular DNAs (eccDNAs) are prevalent in cancer genomes and emerge as a class of crucial yet less characterized oncogenic drivers. However, the structure, composition, genome-wide frequency, and contribution of eccDNAs in HCC, one of the most fatal and prevalent cancers, remain unexplored. In this study, we provide a comprehensive characterization of eccDNAs in human HCC and demonstrate an oncogenic role of microRNA (miRNA)-17-92-containing eccDNAs in tumor progression.

APPROACH AND RESULTS

Using the circle-sequencing method, we identify and characterize more than 230,000 eccDNAs from 4 paired samples of HCC tumor and adjacent nontumor liver tissues. EccDNAs are highly enriched in HCC tumors, preferentially originate from certain chromosomal hotspots, and are correlated with differential gene expression. Particularly, a series of eccDNAs carrying the miRNA-17-92 cluster are validated by outward PCR and Sanger sequencing. Quantitative PCR analyses reveal that miRNA-17-92-containing eccDNAs, along with the expression of their corresponding miRNAs, are elevated in HCC tumors and associated with poor outcomes and the age of HCC patients. More intriguingly, exogenous expression of artificial DNA circles harboring the miR-17-92 cluster, which is synthesized by the ligase-assisted minicircle accumulation method, can significantly accelerate HCC cell proliferation and migration.

CONCLUSIONS

These findings delineate the genome-wide eccDNAs profiling of HCC and highlight the functional significance of miRNA-containing eccDNAs in tumorigenesis, providing insight into HCC pathogenesis and cancer therapy, as well as eccDNA and miRNA biology.

A novel recombinant ORF7-siRNA delivered by flexible nano-liposomes inhibits varicella zoster virus infection

BACKGROUND

Varicella zoster virus (VZV), which is a human restricted alpha-herpesvirus, causes varicella (chickenpox) and zoster (shingles). The subsequent post-herpetic neuralgia (PHN) due to VZV infection is excruciating for most patients. Thus, developing specific therapeutics against VZV infection is imperative. RNA interference (RNAi) represents an effective approach for alternative antiviral therapy. This study aimed to develop a novel anti-VZV therapeutics based on RNAi.

RESULTS

In this study, we screened and found the open reading frame 7 (ORF7) of the VZV genome was an ideal antiviral target based on RNAi. Therefore, a novel siRNA targeting ORF7 (si-ORF7) was designed to explore the potential of RNAi antiviral treatment strategy toward VZV. We used a bio-engineering approach to manufacture recombinant siRNA agents with high yield in E. coli. Then, the efficacy of recombinant ORF7-siRNA (r/si-ORF7) in inhibiting VZV infection both in cellular level and 3D human epidermal skin model was evaluated. The r/si-ORF7 was proved to inhibit the VZV replication and reduce the virus copy numbers significantly in vitro. Furthermore, flexible nano-liposomes were established to deliver r/si-ORF7 to 3D human epidermal skin model and found r/si-ORF7 also could inhibit the VZV infection, thus maintaining normal skin morphology.

CONCLUSIONS

Taken together, our results highlighted that transdermal administration of antiviral r/si-ORF7 was a promising therapeutic strategy for functional cure of VZV infection.

Circular RNAs in hepatocellular carcinoma: biogenesis, function, and pathology

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Both genetic and environmental factors through a multitude of underlying molecular mechanisms participate in the pathogenesis of HCC. Recently, numerous studies have shown that circular RNAs (circRNAs), an emerging class of non-coding RNAs characterized by the presence of covalent bonds linking 3' and 5' ends, play an important role in the initiation and progression of cancers, including HCC. In this review, we outline the current status of the field of circRNAs, with an emphasis on the functions and mechanisms of circRNAs in HCC and its microenvironment. We also summarize and discuss recent advances of circRNAs as biomarkers and therapeutic targets. These efforts are anticipated to throw new insights into future perspectives about circRNAs in basic, translational and clinical research, eventually advancing the diagnosis, prevention and treatment of HCC.

Fasting: From Physiology to Pathology

Overnutrition is a risk factor for various human diseases, including neurodegenerative diseases, metabolic disorders, and cancers. Therefore, targeting overnutrition represents a simple but attractive strategy for the treatment of these increasing public health threats. Fasting as a dietary intervention for combating overnutrition has been extensively studied. Fasting has been practiced for millennia, but only recently have its roles in the molecular clock, gut microbiome, and tissue homeostasis and function emerged. Fasting can slow aging in most species and protect against various human diseases, including neurodegenerative diseases, metabolic disorders, and cancers. These centuried and unfading adventures and explorations suggest that fasting has the potential to delay aging and help prevent and treat diseases while minimizing side effects caused by chronic dietary interventions. In this review, recent animal and human studies concerning the role and underlying mechanism of fasting in physiology and pathology are summarized, the therapeutic potential of fasting is highlighted, and the combination of pharmacological intervention and fasting is discussed as a new treatment regimen for human diseases.

Targeting RNA G-quadruplex with repurposed drugs blocks SARS-CoV-2 entry

The rapid emergence of SARS-CoV-2 variants of concern, the complexity of infection, and the functional redundancy of host factors, underscore an urgent need for broad-spectrum antivirals against the continuous COVID-19 pandemic, with drug repurposing as a viable therapeutic strategy. Here we report the potential of RNA G-quadruplex (RG4)-targeting therapeutic strategy for SARS-CoV-2 entry. Combining bioinformatics, biochemical and biophysical approaches, we characterize the existence of RG4s in several SARS-CoV-2 host factors. In silico screening followed by experimental validation identify Topotecan (TPT) and Berbamine (BBM), two clinical approved drugs, as RG4-stabilizing agents with repurposing potential for COVID-19. Both TPT and BBM can reduce the protein level of RG4-containing host factors, including ACE2, AXL, FURIN, and TMPRSS2. Intriguingly, TPT and BBM block SARS-CoV-2 pseudovirus entry into target cells in vitro and murine tissues in vivo. These findings emphasize the significance of RG4 in SARS-CoV-2 pathogenesis and provide a potential broad-spectrum antiviral strategy for COVID-19 prevention and treatment.

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.

Acute Pancreatitis: Diagnosis and Treatment

Acute pancreatitis is a common indication for hospital admission, increasing in incidence, including in children, pregnancy and the elderly. Moderately severe acute pancreatitis with fluid and/or necrotic collections causes substantial morbidity, and severe disease with persistent organ failure causes significant mortality. The diagnosis requires two of upper abdominal pain, amylase/lipase ≥ 3 ×upper limit of normal, and/or cross-sectional imaging findings. Gallstones and ethanol predominate while hypertriglyceridaemia and drugs are notable among many causes. Serum triglycerides, full blood count, renal and liver function tests, glucose, calcium, transabdominal ultrasound, and chest imaging are indicated, with abdominal cross-sectional imaging if there is diagnostic uncertainty. Subsequent imaging is undertaken to detect complications, for example, if C-reactive protein exceeds 150 mg/L, or rarer aetiologies. Pancreatic intracellular calcium overload, mitochondrial impairment, and inflammatory responses are critical in pathogenesis, targeted in current treatment trials, which are crucially important as there is no internationally licenced drug to treat acute pancreatitis and prevent complications. Initial priorities are intravenous fluid resuscitation, analgesia, and enteral nutrition, and when necessary, critical care and organ support, parenteral nutrition, antibiotics, pancreatic exocrine and endocrine replacement therapy; all may have adverse effects. Patients with local complications should be referred to specialist tertiary centres to guide further management, which may include drainage and/or necrosectomy. The impact of acute pancreatitis can be devastating, so prevention or reduction of the risk of recurrence and progression to chronic pancreatitis with an increased risk of pancreas cancer requires proactive management that should be long term for some patients.