Acinar cells and the development of pancreatic fibrosis

Advances in the pharmacological mechanisms of berberine in the treatment of fibrosis

The rising incidence of fibrosis poses a major threat to global public health, and the continuous exploration of natural products for the effective treatment of fibrotic diseases is crucial. Berberine (BBR), an isoquinoline alkaloid, is widely used clinically for its anti-inflammatory, anti-tumor and anti-fibrotic pharmacological effects. Until now, researchers have worked to explore the mechanisms of BBR for the treatment of fibrosis, and multiple studies have found that BBR attenuates fibrosis through different pathways such as TGF-β/Smad, AMPK, Nrf2, PPAR-γ, NF-κB, and Notch/snail axis. This review describes the anti-fibrotic mechanism of BBR and its derivatives, and the safety evaluation and toxicity studies of BBR. This provides important therapeutic clues and strategies for exploring new drugs for the treatment of fibrosis. Nevertheless, more studies, especially clinical studies, are still needed. We believe that with the continuous implementation of high-quality studies, significant progress will be made in the treatment of fibrosis.

Dachaihu Decoction alleviates chronic pancreatitis by regulating MAPK signaling pathway: Insights from network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic pancreatitis (CP), a syndrome characterized by inflammatory fibrosis, can impair both the internal and external secretory functions of the pancreas. The global incidence of this disease is gradually increasing. However, the exact pathogenesis remains unclear, resulting in a lack of targeted clinical therapies. According to the principles of traditional Chinese medicine, CP can be attributed to Shaoyang and Yangming syndromes, which manifest as abdominal pain and hypochondriac distension. Dachaihu Decoction (DCHD) is a classic formula from the "Treatise on Febrile and Miscellaneous Disease." It is frequently prescribed for conditions associated with combined Shaoyang and Yangming syndromes. However, the specific mechanisms by which DCHD prevents and treats CP remain unclear and require further investigation.

AIM OF THE STUDY

Using a holistic methodology, including network pharmacology, molecular docking, transcriptomic profiling, and animal experimentation, we explored the potential therapeutic mechanisms of DCHD in CP.

MATERIALS AND METHODS

In a mouse model, caerulein was used to induce CP, and DCHD was administered via gastric lavage to assess its therapeutic effect on pancreatic injury caused by caerulein-induced CP. Subsequently, pancreatic tissues were collected for transcriptomic analysis. Screening of DCHD-active ingredient-target pathways for CP treatment was conducted using network pharmacology and further preliminary validation was performed using molecular docking techniques. Additionally, in vivo and in vitro validation was conducted using animal and cells experiments based on the predicted results.

RESULTS

Our findings suggest that DCHD ameliorates pancreatic acinar cell injury, pancreatic inflammation, and fibrosis in mice with CP. Network pharmacology identified 385 potential targets of DCHD associated with CP. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the therapeutic effect of DCHD on CP may be linked to the mitogen-activated protein kinase (MAPK) signaling pathway. Transcriptomic data supported this finding, as it confirmed that DCHD inhibited the pancreatic MAPK signaling pathway in CP. Molecular docking studies further revealed that the top ten active components of DCHD exhibited strong docking activity with key molecules within the MAPK signaling pathway. Finally, animal experiments confirmed that DCHD effectively reduced the phosphorylation of P38, Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) in pancreatic tissues. In addition, the expression of p-P38, p-JNK, and p-ERK was reduced in pancreatic stellate cells and macrophages in the DCHD group. We further treated CP mice, human pancreatic stellate cell line (hPSCs), and macrophage cell line RAW264.7 with the active component baicalin from DCHD, and found that baicalin effectively reduced pancreatic damage in CP. Additionally, the expression of key proteins in the MAPK signaling pathway was significantly decreased in both hPSCs and RAW264.7.

CONCLUSION

In summary, DCHD plays an important role in the treatment of chronic pancreatitis, and it may become a promising drug against the progression of CP. The role of DCHD in alleviating pancreatic inflammatory cell infiltration and fibrosis may be related to the regulation of the MAPK signaling pathway.

Metabolism and bioenergetics in the pathophysiology of organ fibrosis

Fibrosis is the tissue scarring characterized by excess deposition of extracellular matrix (ECM) proteins, mainly collagens. A fibrotic response can take place in any tissue of the body and is the result of an imbalanced reaction to inflammation and wound healing. Metabolism has emerged as a major driver of fibrotic diseases. While glycolytic shifts appear to be a key metabolic switch in activated stromal ECM-producing cells, several other cell types such as immune cells, whose functions are intricately connected to their metabolic characteristics, form a complex network of pro-fibrotic cellular crosstalk. This review purports to clarify shared and particular cellular responses and mechanisms across organs and etiologies. We discuss the impact of the cell-type specific metabolic reprogramming in fibrotic diseases in both experimental and human pathology settings, providing a rationale for new therapeutic interventions based on metabolism-targeted antifibrotic agents.

Down-regulation of microRNA-23a promotes pancreatic ductal adenocarcinoma initiation and progression by up-regulation of FOXM1 expression

Transcriptional factor Forkhead box M1 (FOXM1) plays an important role in pancreatic ductal adenocarcinoma (PDAC) development and progression. The molecular mechanisms underlying its dysregulation remain unclear. We identified and functionally validated the microRNAs (miRNAs) that critically regulate FOXM1 expression in PDAC. The expression levels of miRNA-23a (miR-23a-3p and -5p) were altered in PDAC cell lines and their effects on FOXM1 signaling and cell proliferation and migration and tumorigenesis were examined in vitro and in vivo using mouse PDAC models. Compared with non-tumor pancreatic tissues, PDAC tissues and cell lines exhibited significantly reduced levels of miR-23a expression. Reduced miR-23a expression and concomitant increase in FOXM1 expression were also observed in acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasia, the major premalignant lesions of PDAC. Transgenic expression of miR-23a reduced the expression of FOXM1 and suppressed cell proliferation and migration in PDAC cells, whereas the inhibitors of miR-23a did the opposite. Loss or reduced levels of miR-23a increased the levels of FOXM1 expression, while increased expression of FOXM1 down-regulated miR-23a expression, suggesting that miR-23a and FOXM1 were mutual negative regulators of their expression in PDAC cells. Therefore, the miR-23a/FOXM1 signaling axis is important in PDAC initiation and progression and could serve as an interventional or therapeutic target for patients with early or late stages of PDAC.

Saikosaponin d protects pancreatic acinar cells against cerulein-induced pyroptosis through alleviating mitochondrial damage and inhibiting cGAS-STING pathway

Acute pancreatitis represents an inflammatory disease featuring pancreatic necrosis and inflammation. Inflammatory injury of pancreatic acinar cells (PACs) is critically involved in the initiation and progression of acute pancreatitis. Pyroptosis, a new kind of programmed cell death concomitant with a low-grade inflammatory reaction, plays a function in acute pancreatitis pathology. It is unclear whether saikosaponin d (SSd), a pharmacologically active natural product, could protect PACs by regulating pyroptosis. Here, we established a PAC injury model in vitro using cerulein to treat AR42J cells. SSd restored viability and proliferation and lowered the release of pancreatic enzymes and inflammatory interleukins in cerulein-treated AR42J cells. Cerulein-induced pyroptosis was evidenced by typical ultrastructural changes and NLRP3/caspase-1 activation in AR42J cells, but SSd attenuated cerulein-induced pyroptosis and inhibited NLRP3/caspase-1 pathway. Mechanically, SSd reduced mitochondrial damage and mtDNA release, and blocked cGAS-STING signaling in AR42J cells treated with cerulein, contributing to the inhibition of NLRP3-mediated pyroptosis. Furthermore, SSd abolished cerulein-elevated oxidative stress in AR42J cells, leading to the mitigation of mitochondrial damage and inhibition of cGAS-STING signaling and pyroptosis. In conclusion, SSd protected PACs against cerulein-induced pyroptosis by alleviating mitochondrial damage and inhibiting the cGAS-STING pathway, and it could be a therapeutic candidate for acute pancreatitis.

Pirfenidone alleviates fibrosis by acting on tumour-stroma interplay in pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a malignancy with a 5-year survival rate of 12%. The abundant mesenchyme is partly responsible for the malignancy. The antifibrotic therapies have gained attention in recent research. However, the role of pirfenidone, an FDA-approved drug for idiopathic pulmonary fibrosis, remains unclear in PDAC.

METHODS

Data from RNA-seq of patient-derived xenograft (PDX) models treated with pirfenidone were integrated using bioinformatics tools to identify the target of cell types and genes. Using confocal microscopy, qRT-PCR and western blotting, we validated the signalling pathway in tumour cells to regulate the cytokine secretion. Further cocultured system demonstrated the interplay to regulate stroma fibrosis. Finally, mouse models demonstrated the potential of pirfenidone in PDAC.

RESULTS

Pirfenidone can remodulate multiple biological pathways, and exerts an antifibrotic effect through inhibiting the secretion of PDGF-bb from tumour cells by downregulating the TGM2/NF-kB/PDGFB pathway. Thus, leading to a subsequent reduction in collagen X and fibronectin secreted by CAFs. Moreover, the mice orthotopic pancreatic tumour models demonstrated the antifibrotic effect and potential to sensitise gemcitabine.

CONCLUSIONS

Pirfenidone may alter the pancreatic milieu and alleviate fibrosis through the regulation of tumour-stroma interactions via the TGM2/NF-kB/PDGFB signalling pathway, suggesting potential therapeutic benefits in PDAC management.

Activation and Regulation of Pancreatic Stellate Cells in Chronic Pancreatic Fibrosis: A Potential Therapeutic Approach for Chronic Pancreatitis

In the complex progression of fibrosis in chronic pancreatitis, pancreatic stellate cells (PSCs) emerge as central figures. These cells, initially in a dormant state characterized by the storage of vitamin A lipid droplets within the chronic pancreatitis microenvironment, undergo a profound transformation into an activated state, typified by the secretion of an abundant extracellular matrix, including α-smooth muscle actin (α-SMA). This review delves into the myriad factors that trigger PSC activation within the context of chronic pancreatitis. These factors encompass alcohol, cigarette smoke, hyperglycemia, mechanical stress, acinar cell injury, and inflammatory cells, with a focus on elucidating their underlying mechanisms. Additionally, we explore the regulatory factors that play significant roles during PSC activation, such as TGF-β, CTGF, IL-10, PDGF, among others. The investigation into these regulatory factors and pathways involved in PSC activation holds promise in identifying potential therapeutic targets for ameliorating fibrosis in chronic pancreatitis. We provide a summary of recent research findings pertaining to the modulation of PSC activation, covering essential genes and innovative regulatory mediators designed to counteract PSC activation. We anticipate that this research will stimulate further insights into PSC activation and the mechanisms of pancreatic fibrosis, ultimately leading to the discovery of groundbreaking therapies targeting cellular and molecular responses within these processes.