Macrophages in pancreatitis: Mechanisms and therapeutic potential. Biomed Pharmacother. 2020;131:110693. [PMID: 32882586 DOI: 10.1016/j.biopha.2020.110693]

Toll-like receptors in kidney ischemia-reperfusion injury: Modulating macrophage responses for therapeutic insights

Kidney ischemia-reperfusion (I/R) injury is an acute clinical condition associated with inflammation and tissue damage during and after ischemia and reperfusion periods. In I/R injury, macrophages contribute to injury, and a family of proteins called toll-like receptors seem to have an immune modulatory role. When activated, TLRs initiate a series of signaling pathways, including MyD88 and TRIF. These pathways regulate the activation of tissue macrophages into either 'classically activated' M1 or 'alternatively activated' M2 phenotypes. Indeed, the relative abundance of these macrophage phenotypes defines the tissue injury level, which consequently requires reparative processes. The initial effector pro-inflammatory M1 macrophages aggravate tissue injury. Conversely, tissue reparative and anti-inflammatory M2 macrophages promote tissue repair and resolution-increased TLR signalling results in increased inflammation, prolonged healing and even renal failure. New evidence indicates that the change of macrophage responses through pharmacological targeting of the TLR pathways that regulate inflammation and tissue repair may have therapeutic implications. Some experimental treatment methods, in which early phases have been elaborated through experimental animal models, are TLR antagonists, small molecule inhibitors and nanotechnology-based delivery systems for Antisense oligonucleotide. Nevertheless, because the pathways regulated by TLRs and the subsets of macrophages are so countless and entangled, more extensive study is needed to provide more targeted actions. These findings shed light on the role and regulation of TLRs in macrophages during kidney I/R injury and investigate potential treatments with the potential to enhance care in this highly damaging condition.

Exosomes in acute pancreatitis: Pathways to cellular death regulation and clinical application potential

Acute pancreatitis (AP) is a severe inflammatory condition of the digestive system which, in severe cases, can lead to persistent organ failure (POF). Developing novel therapeutic interventions and diagnostic biomarkers is critical to improve the management and prognosis of this disease. Exosomes, small extracellular vesicles, can reflect the inflammatory state of the pancreas, providing valuable insights into disease progression. Moreover, these vesicles are essential mediators of intercellular communication, modulating inflammatory responses by affecting patterns of cell death and macrophage polarization-key factors in determining AP clinical outcomes. Their stability, bioavailability, and capacity to transport various bioactive molecules render exosomes promising tools for early diagnosis and precision therapy, potentially enhancing patient outcomes. This review highlights the innovative potential of exosomes in transforming the management of AP, providing a foundation for more accurate diagnostics and targeted treatments with clinical applicability.

Exosomes and MicroRNAs: key modulators of macrophage polarization in sepsis pathophysiology

Sepsis is a highly dangerous and complex condition that can result in death. It is characterized by a strong reaction to an infection, causing dysfunction in multiple bodily systems and a high risk of mortality. The transformation of macrophages is a vital stage in the procedure as they possess the capability to interchange between two separate types: M1, which promotes inflammation, and M2, which inhibits inflammation. The choice greatly affects the immune response of the host. This analysis underscores the rapidly expanding roles of exosomes and microRNAs (miRNAs) in regulating the trajectory of macrophage polarization during episodes of sepsis. Exosomes, extremely small extracellular vesicles, facilitate cellular communication by transferring biologically active compounds, including miRNAs, proteins, and lipids. We investigate the impact of changes in exosome production and composition caused by sepsis on macrophage polarization and function. Unique microRNAs present in exosomes play a significant role in controlling crucial signaling pathways that govern the phenotype of macrophages. Through thorough examination of recent progress in this area, we clarify the ways in which miRNAs derived from exosomes can either aggravate or alleviate the inflammatory reactions that occur during sepsis. This revelation not only deepens our comprehension of the underlying mechanisms of sepsis, but it also reveals potential new biomarkers and targets for treatment. This assessment aims to amalgamate diverse research investigations and propose potential avenues for future investigations on the influence that exosomes and miRNAs have on macrophage polarization and the body's response to sepsis. These entities are essential for controlling the host's reaction to sepsis and hold important functions in this mechanism.

Kinsenoside alleviates experimental acute pancreatitis by suppressing M1 macrophage polarization via the TLR4/STAT1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Acute pancreatitis (AP) is an inflammatory disease that can progress to systemic immune responses and multi-organ damage in its severe forms. Anoectochilus roxburghii (Wall.) Lindl. (AR), a traditional Chinese medicinal plant, has been reported to exhibit anti-inflammatory, hypoglycemic, hepatoprotective, and analgesic properties. Kinsenoside (KD), the primary bioactive glycoside in AR, is responsible for many of its therapeutic effects. Given its anti-inflammatory and immunomodulatory properties, KD may have the potential to mitigate pancreatic inflammation in AP. However, its protective role in AP has not yet been investigated.

AIM OF THE STUDY

This study aimed to investigate the protective effects of the natural active compound KD against acute pancreatitis (AP) and its associated molecular mechanisms.

MATERIALS AND METHODS

Two AP mouse models were established: one by intraperitoneal injection of caerulein combined with lipopolysaccharide (LPS) and the other by retrograde injection of sodium taurocholate (NaT) into the biliopancreatic duct. KD (2.5, 5, 10 mg/kg) was administered as a pre-treatment 1 h before the induction of AP. The severity of AP was evaluated through histopathological analysis, while macrophage infiltration and phenotypic changes in pancreatic tissues were examined using immunofluorescence staining and flow cytometry. Bone marrow-derived macrophages (BMDMs) were polarized into the M1 phenotype through two distinct methods: stimulation with LPS and interferon-γ (IFNγ) and indirect co-culture with pancreatic acinar cells. Changes in macrophage phenotype after KD supplementation (100, 200, and 400 μM) were analyzed using quantitative Reverse Transcription PCR (qRT-PCR) and flow cytometry. Network pharmacology and transcriptomic sequencing were utilized to identify potential targets and pathways affected by KD, with validation of key signaling pathways performed through qPCR and Western blot analysis.

RESULTS

In two models of AP mice, KD at a high dose (10 mg/kg) significantly alleviated pancreatic damage. It reduced pancreatic edema, necrosis, and inflammatory cell infiltration, with a notable decrease in macrophage infiltration. Furthermore, KD (10 mg/kg) administration significantly reduced serum lipase by 53.62% in the Caerulein + LPS model and 41.14% in the NaT model, as well as amylase by 28.13% and 27.99%, respectively. Additionally, KD (10 mg/kg) administration mitigated systemic inflammation and lung injury during AP. Both in vivo and in vitro experiments demonstrated that KD (400 μM) significantly reduced the proportion of M1 macrophages. Furthermore, KD (400 μM) downregulated the mRNA expression of M1-associated genes, including Nos2, Tnf, Il1b, and Il6, in macrophages stimulated by both LPS + IFNγ and pancreatic acinar cell-conditioned media. Network pharmacology and transcriptomic analyses identified toll-like receptor 4 (TLR4) as a potential target of KD in the context of AP. KD (400 μM) was shown to inhibit the activation of the TLR4/STAT1 signaling pathway in macrophages exposed to inflammatory stimuli.

CONCLUSIONS

KD administration mitigated experimental AP induced by diverse etiologies through the inhibition of M1 macrophage polarization via the TLR4/STAT1 signaling pathway. These findings highlight KD as a promising therapeutic candidate with potential clinical applications in the management of AP.

Transcriptomic characterization of human pancreatic CD206- and CD206 + macrophages

Macrophages reside in all organs and participate in homeostatic- and immune regulative processes. Little is known about pancreatic macrophage gene expression. In the present study, global gene expression was characterized in human pancreatic macrophage subpopulations. CD206- and CD206 + macrophages were sorted separately from pancreatic islets and exocrine tissue to high purity using flow cytometry, followed by RNA-seq analysis. Comparing CD206- with CD206 + macrophages, CD206- showed enrichment in histones, proliferation and cell cycle regulation, glycolysis and SPP1-associated immunosuppressive polarization while CD206 + showed enrichment in complement and coagulation-, IL-10 and IL-2RA immune regulation, as well as scavenging-related gene sets. Comparing islet CD206- with exocrine CD206-, enrichments in islet samples included two sets involved in immune regulation, while enrichments in exocrine samples included sets related to extracellular matrix and immune activation. Fewer differences were found between CD206 + macrophages, with enrichments in islet samples including two IL2-RA related gene sets, while enrichments in exocrine samples included sets related to extracellular matrix and immune activation. Comparing macrophages between individuals with normoglycemia, elevated HbA1c or type 2 diabetes, only a few diverse differentially expressed genes were identified. This work characterizes global gene expression and identifies differences between CD206- and CD206 + macrophage populations within the human pancreas.

Annexin A1 regulates inflammatory-immune response and reduces pancreatic and extra- pancreatic injury during severe acute pancreatitis

Severe acute pancreatitis (SAP) poses significant challenges due to its complex pathophysiology, which includes inflammatory-immune responses that cause considerable damage to both the pancreas and other tissues. In this study, we explored the role of Annexin A1 (Anxa1), a glucocorticoid-regulated protein recognized for its anti-inflammatory properties, in regulating inflammation during acute pancreatitis. Using flow cytometry, single-cell RNA sequencing, and gene expression analysis, we examined how Anxa1 expression is regulated in myeloid cells throughout acute pancreatitis, employing various animal models to evaluate the consequences of modulating Anxa1 on injuries induced by SAP. Our findings revealed dynamic regulation of Anxa1 expression in myeloid cells, with mice lacking Anxa1 exhibiting worsened pancreatic injury and heightened systemic inflammation, resulting in significant damage to extra-pancreatic organs such as the lungs, liver, and kidneys. In contrast, treatment with Ac2-26, a synthetic peptide derived from Anxa1, effectively mitigated both pancreatic and extra-pancreatic inflammation and tissue damage. Overall, this study highlights the critical role of Anxa1 in modulating inflammatory responses during acute pancreatitis. Targeting Anxa1 presents a promising therapeutic strategy to mitigate pancreatic injury and prevent systemic complications associated with severe acute pancreatitis.

Circulating Biomarkers of Macrophage Activation in Different Stages of Chronic Pancreatitis: A Pilot Study

OBJECTIVES

Activation of type M2 macrophages has been implicated in the pathogenesis of chronic pancreatitis (CP). In a clinical pilot study, we investigated blood-based markers of macrophage activation at different stages of CP.

MATERIALS AND METHODS

We performed a cross-sectional analysis of prospectively collected plasma samples from healthy controls and patients with suspected or definitive CP according to the M-ANNHEIM criteria. Plasma concentrations of soluble CD163 (sCD163), soluble CD206 (sCD206), and monocyte chemoattractant protein-1 (MCP-1) were analyzed using enzyme-linked immunosorbent assays. Group and pairwise comparisons of analytes were performed using regression models and area under the receiver operating curves (AUC-ROC).

RESULTS

In total, 73 subjects with CP (28 suspected CP and 45 definitive CP) and 40 controls were included. Compared to controls, the median plasma concentrations of sCD163 ( P  = 0.019) and sCD206 ( P  = 0.033) were elevated in patients with definitive CP. sCD206 was also elevated in patients with definitive CP ( P  = 0.042) compared to suspected CP. ROC analysis revealed the optimal sCD163 cutpoint to distinguish definitive CP from controls was 1.84 mg/mL (AUC-ROC 0.65; 95% confidence interval [CI], 0.54-0.77). The optimal sCD206 cutpoint to distinguish definitive CP from controls was 0.24 mg/mL (AUC-ROC 0.66; 95% CI, 0.54-0.78). MCP-1 concentrations showed no differences across subgroups.

CONCLUSION

Our study demonstrates that subjects with definitive CP, sampled during a clinically quiescent phase, exhibited increased levels of sCD163 and sCD206. This indicates the presence of activated M2 macrophages in patients with CP at advanced, but not early, clinical stages.

Targeted inhibitors of S100A9 alleviate chronic pancreatitis by inhibiting M2 macrophage polarization via the TAOK3-JNK signaling pathway

Background

Chronic pancreatitis (CP) is a fibro-inflammatory syndrome with unclear pathogenesis and futile therapy. CP's microenvironment disrupts the fine-tuned balance of macrophage polarization toward a predominance of the M2-like phenotype associated with fibrosis. S100A9 is mainly expressed in monocytes as a potent regulator of macrophage phenotype and function. Here, we investigated the S100A9-related mechanisms underlying CP pathology induced by macrophages polarization.

Methods

S100a9 knockout (S100a9 -/-) mice and an in vitro coculture system of macrophages overexpressing S100a9 and primary PSCs were constructed to investigate the effects and mechanisms of S100A9-mediated macrophage polarization on pancreatic inflammation and fibrosis underpinning CP pathology. Furthermore, a variety of S100A9-targeted small-molecule compounds were screened from U.S. Food and Drug Administration (FDA)-listed drug libraries through molecular docking and virtual screening techniques.

Results

In CP progression, S100A9 upregulation induces M2 macrophage polarization to accelerate fibrosis via thousand-and-one amino acid kinase 3 (TAOK3)-c-Jun N-terminal kinase (JNK) signaling pathway, and loss of S100A9 reduces CP injury in vitro and in vivo. Coimmunoprecipitation (co-IP) and molecular docking experiments proved that S100A9 may interact directly with TAOK3 through salt bridges and hydrogen bonding interactions of the residues in the S100A9 protein. Furthermore, cobamamide and daptomycin, as inactivators of the S100A9-TAOK3 interaction, can improve CP by inhibiting the polarization of M2 macrophages.

Conclusions

S100A9 is a significant promoter of M2-like macrophage-induced fibrosis in CP via the TAOK3-JNK signaling pathway. Cobamamide and daptomycin, targeted inhibitors of the S100A9-TAOK3 interaction, may become candidate drugs for CP immunotherapy.

Genome Mining for Hub Genes Related to Endoplasmic Reticulum Stress in Pancreatitis: A Perspective from In Silico Characterization

Pancreatitis, as a common exocrine pancreatic disease, poses a daunting challenge to patients' health and the medical system. Endoplasmic reticulum stress (ERS) plays an essential role in the pathologic process of pancreatitis. However, its mechanism is not fully understood. Therefore, this study was designed to deepen the understanding of the pathogenic mechanism of the disease by screening key ERS-related genes (ERSRGs) associated with pancreatitis. Pancreatitis mRNA data for GSE194331 (Normal: 32, Pancreatitis: 87) and pancreatitis GSE143754 (Normal: 9, Pancreatitis: 6) were downloaded from the GEO database and were used as a training and validation set, respectively. First, the training set GSE194331 was differentially expressed and intersected with the ERSRGs (n = 265) obtained from the MSigDB database to result in 42 differentially expressed ERSRGs (DE-ERSRGs). Subsequently, five candidate genes were further screened by PPI network and MCC and MCODE algorithms. However, according to the ROC curve results, AUC values of CCND1, BCL2, PIK3R1, and BCL2L1 were all greater than 0.6, indicating that they had good diagnostic performance, which was verified by the GSE143754 data set. Based on the GeneMANIA network, it was found that hub genes BCL2 and BCL2L1 may be the key factors in the regulation of mitochondrial metabolism. 24 differentially expressed pancreatitis-related genes (DE-PRGs) were found by difference analysis and Venn analysis. Hub genes BCL2 and PIK3R1 that were significantly correlated with 24 DE-PRGs were determined by Spearman analysis. ssGSEA algorithm was further used to reveal the significant correlation between these hub genes and the immune microenvironment of pancreatitis. The miRNA and lncRNA targeting hub genes were predicted using miRWalk, TargetScan, miRDB, and ENCORI databases, providing research directions for the mechanism of pancreatitis. Finally, the Network Analyst website was used to predict potential compounds associated with the hub gene. In conclusion, this study not only further supports the role of ERS in the development of pancreatitis but also provides a new perspective and direction for the development of biomarkers and mechanism of pancreatitis. At the same time, the results of this study provide a reliable research direction for the targeted treatment of pancreatitis.

Biotechnological advances in 3D modeling of cancer initiation. Examples from pancreatic cancer research and beyond

In recent years, biofabrication technologies have garnered significant attention within the scientific community for their potential to create advancedin vitrocancer models. While these technologies have been predominantly applied to model advanced stages of cancer, there exists a pressing need to develop pertinent, reproducible, and sensitive 3D models that mimic cancer initiation lesions within their native tissue microenvironment. Such models hold profound relevance for comprehending the intricacies of cancer initiation, to devise novel strategies for early intervention, and/or to conduct sophisticated toxicology assessments of putative carcinogens. Here, we will explain the pivotal factors that must be faithfully recapitulated when constructing these models, with a specific focus on early pancreatic cancer lesions. By synthesizing the current state of research in this field, we will provide insights into recent advances and breakthroughs. Additionally, we will delineate the key technological and biological challenges that necessitate resolution in future endeavors, thereby paving the way for more accurate and insightfulin vitrocancer initiation models.

YAP promotes fibrosis by regulating macrophage to myofibroblast transdifferentiation and M2 polarization in chronic pancreatitis

Chronic pancreatitis (CP) is a clinical entity characterized by progressive inflammation and irreversible fibrosis of the pancreas, which ultimately leads to exocrine and/or endocrine insufficiency as well as an increased risk of pancreatic cancer. Currently, there are no specific or effective approved therapies for CP. Herein, we show that macrophage to myofibroblast transdifferentiation (MMT) and M2 macrophage polarization are associated with both human CP and CP experimental mouse models. In addition, we show YAP is activated in macrophages during CP. Furthermore, we used the YAP agonist XMU-MP-1 (XMU) and the YAP inhibitor Verteporfin (VP) to modulate YAP expression levels. In vitro experiments revealed that XMU upregulated YAP expression, thereby promoting MMT and enhancing M2 macrophage polarization; conversely, VP downregulated YAP expression, inhibiting these effects. In vivo studies indicated that XMU exacerbated acinar cell atrophy and interstitial fibrosis in caerulein-induced mouse models of CP, while VP mitigated these adverse effects associated with CP. These findings provide new insights into the pathogenic mechanisms underlying CP, and offer potential therapeutic targets for CP.

FIBRINOGEN-LIKE PROTEIN 2 PROTECTS THE AGGRAVATION OF HYPERTRIGLYCERIDEMIA ON THE SEVERITY OF HYPERTRIGLYCERIDEMIA ACUTE PANCREATITIS BY REGULATING MACROPHAGES

ABSTRACT

Objective: The mechanisms underlying the increased severity of hypertriglyceridemia acute pancreatitis (HTG-AP) remain poorly understood. Fibrinogen-like protein 2 (FGL2) has been identified as a regulator of macrophage activity, mediating immune suppression. This study aims to examine the role of FGL2 in the susceptibility to severe conditions of HTG-AP. Methods: Both wild-type and FGL2 gene knockout C57BL/6 mice were utilized to establish HTG, AP, and HTG-AP models using P-407 and/or caerulein. Serum levels of triglycerides, total cholesterol, amylase, and lipase were assessed via biochemical analysis. Pancreatic and lung tissue injuries were evaluated using hematoxylin and eosin staining. TNF-α, IL-1β, and IL-6 levels in serum and pancreatic tissues were quantified using enzyme-linked immunosorbent assay. Immunohistochemistry was used to assess the expression of FGL2, the macrophage marker CD68, and M1/M2 macrophage markers iNOS/CD163. Results: The animal models were successfully established. Compared to wild-type mice, FGL2 knockout resulted in increased pathological injury scores in the pancreas and lungs, as well as elevated TNF-α, IL-1β, and IL-6 levels in serum and pancreatic tissue in the HTG group, with more pronounced effects observed in the HTG-AP group. The AP group alone did not exhibit significant changes due to FGL2 knockout. Further analysis revealed that FGL2 knockout increased CD68 expression but reduced CD163 expression in the pancreatic tissues in the HTG group. In the HTG-AP group, there was a marked increase in CD68 and iNOS expressions, coupled with a reduction in CD163 expression. Conclusion: FGL2 knockout in HTG and HTG-AP mice resulted in increased inflammatory responses and a significant imbalance in M2 macrophages. These findings suggest that FGL2 plays a crucial role in mitigating the aggravation of HTG on the severity of HTG-AP by modulating macrophage activity.

Macrophage-mimicking nanotherapy for attenuation of acute pancreatitis

Acute pancreatitis (AP) is a highly fatal pancreatic inflammation. In recent years, synthetic nanoparticles have been extensively developed as drug carriers to address the challenges of systemic adverse reactions and lack of specificity in drug delivery. However, systemically administered nanoparticle therapy is rapidly cleared from circulation by the mononuclear phagocyte system (MPS), leading to suboptimal drug concentrations in inflamed tissues and suboptimal pharmacokinetics. To address this challenge, we herein demonstrate a surface masking strategy that involves coating the surface of selenylated Poria cocos polysaccharide nanoparticles with a layer of macrophage plasma membrane to circumvent MPS sequestration, thereby enhancing the therapeutic efficacy of selenylated Poria cocos polysaccharide nanoparticles. Nanoparticles encapsulated with macrophage membranes can simulate the active homing efficacy of macrophages to inflamed lesions during AP, resulting in excessive infiltration of macrophages in pancreatic inflammation sites and prolonged tissue retention time. This technique converts non-adhesive lipid nanoparticles into bioadhesive nanoparticles, increasing local tissue accumulation under inflammatory conditions, including the pancreas and vulnerable lungs. The mechanism is related to targeting pro-inflammatory macrophages. In murine models of mild and severe AP, intravenous treatment with macrophage-mimicking nanoparticles effectively reduces systemic inflammation level and diminishes the recruitment of macrophages and neutrophils. Mechanistic studies elucidate that macrophage membrane-biomimetic selenylated Poria cocos polysaccharide nanoparticles primarily mitigate pancreatic inflammation by inhibiting the AKT/mTOR pathway to reverse autophagic flux impairment. This allows us to envision that the developed biomimetic nanotherapy approach could potentially serve as a novel strategy for pancreatic drug therapy.

YKL-40 as a risk stratification marker in acute pancreatitis: A prospective study

BACKGROUND/OBJECTIVES

Increased systemic concentrations of YKL-40 are seen in various inflammatory conditions. We explored the relationship between the serum YKL-40 concentrations and subsequent disease severity in patients with acute pancreatitis (AP).

METHODS

Consecutive adults with AP were prospectively enrolled, and classified as having mild, moderate or severe disease. On admission and 48 h later, C-reactive protein (CRP), YKL-40, interleukin-6 and 8 (IL-6, IL-8), and tumor necrosis factor alpha (TNF-α) concentrations were measured. Patients were also classified as those with low (<50 ng/mL, in the range seen in 30 age and sex-matched non-AP subjects), high (≥190 ng/mL, seen in most of the other inflammatory conditions), and intermediate YKL-40 (50-189 ng/mL).

RESULTS

Incidence of mild, moderate and severe AP among the 150 enrolled patients was 80 (53.3 %), 59 (39.3 %), and 11 (7.4 %), respectively. Both on admission and 48 h later, high YKL-40 (vs. intermediate or low) was strongly associated with higher odds of a more severe AP, independently of the concurrent IL-8 and TNF-α concentrations (OR around 3.5-4.0, or higher). On admission, the association was independent also of the concurrent CRP, whereas the association between the later concentrations and the outcome was conditional on CRP - uncertain at low, strong at high CRP. The high YKL-40 - outcome association at both time-points was conditional on concurrent IL-6: uncertain if IL-6 was low, strong if IL-6 was high.

CONCLUSIONS

Serum YKL-40 is a plausible candidate for further evaluation as an early biochemical indicator of subsequent AP severity, particularly if considered jointly with CRP and/or IL-6.

Artesunate protects against a mouse model of cerulein and lipopolysaccharide‑induced acute pancreatitis by inhibiting TLR4‑dependent autophagy

Severe acute pancreatitis (SAP) is a severe clinical condition associated with high rates of morbidity and mortality. Multiple organ dysfunction syndrome that follows systemic inflammatory response syndrome is the leading cause of SAP‑related death. Since the inflammatory mechanism of SAP remains unclear, there is currently a lack of effective drugs available for its treatment. Therefore, it is important to study effective therapeutic drugs and their molecular mechanisms based on studying the inflammatory mechanism of SAP. In the present study, in vivo, a mouse model of AP induced by cerulein (CR) combined with lipopolysaccharide (LPS) was established to clarify the therapeutic effect of artesunate (AS) in AP mice by observing the gross morphological changes of the pancreas and surrounding tissues, calculating the pancreatic coefficient, and observing the histopathology of the pancreas. The serum amylase activity in AP mice was detected by iodine colorimetry and the superoxide dismutase activity in the pancreas was detected by WST‑1 assay. The levels of proinflammatory cytokines in the serum, the supernatant of pancreatic tissue homogenates and the peritoneal lavage fluid were detected by ELISA assay. The total number of peritoneal macrophages was assessed using the cellular automatic counter, and the expression of proteins related to autophagy, and the TLR4 pathway was detected by immunohistochemistry and western blotting. In vitro, the effect of trypsin (TP) combined with LPS was observed by detecting the release of proinflammatory cytokine levels from macrophages by ELISA assay, and detecting the expression of proteins related to autophagy and the TLR4 pathway by immunofluorescence and western blotting. The present study revealed that AS reduced pancreatic histopathological damage, decreased pancreatic TP and serum amylase activities, increased superoxide dismutase activity, and inhibited pro‑inflammatory cytokine levels in a mouse model of AP induced by cerulein combined with lipopolysaccharide. In vitro, TP combined with LPS was found to synergistically induce pro‑inflammatory cytokine release from mouse macrophages and RAW264.7 cells, while AS could inhibit cytokine release. Furthermore, CR combined with LPS synergistically increased amylase activity in acinar cells, whereas AS decreased amylase activity. Autophagy serves an important role in the release of pro‑inflammatory cytokines. In the present study, it was revealed that the autophagy inhibitor LY294002 suppressed the release of pro‑inflammatory cytokines from macrophages treated with TP combined with LPS, and pro‑inflammatory cytokine release was not further reduced by AS combined with LY294002. Furthermore, AS not only inhibited the expression of important molecules in the Toll‑like receptor 4 (TLR4) signaling pathway, but also inhibited autophagy proteins and reduced the number of autolysosomes in mice with AP and in macrophages. In conclusion, these results suggested that AS may protect against AP in mice via inhibition of TLR4‑dependent autophagy; therefore, AS may be considered a potential therapeutic agent against SAP.

Based on the immune system: the role of the IL-2 family in pancreatic disease

The IL-2 family, consisting of IL-2, IL-4, IL-7, IL-9, IL-15 and IL-21, is a key regulator of the immune response. As an important endocrine and digestive organ, the function of the pancreas is regulated by the immune system. Studies have shown that each cytokine of the IL-2 family influences the occurrence and development of pancreatic diseases by participating in the regulation of the immune system. In this paper, we review the structural and functional characteristics of IL-2 family members, focus on their molecular mechanisms in pancreatic diseases including acute pancreatitis, chronic pancreatitis and pancreatic cancer, and highlight the importance of the related proteins in the regulation of immune response and disease progression, which will provide valuable insights for new biomarkers in pancreatic diseases, early diagnosis of the diseases, assessment of the disease severity, and development of new therapeutic regimens. The insights of the study are summarized in the following sections.

Sex-dependent modulation of caerulein-induced acute pancreatitis in C57BL/6J mice

Acute pancreatitis (AP) is a life-threatening condition, with a higher mortality rate in men than women and in which estrogens might play a protective role. This study aimed to investigate sex-dependent differences in a mouse model of caerulein-induced AP. Thirty-six C57BL/6J mice (19 females and 17 males) were treated intraperitoneally with phosphate-buffered saline or caerulein, and sacrificed 12 hours, 2 days, or 7 days after the last injection. Blood was collected for amylase, lipase, and glucose determination. Severity and extent of inflammation, apoptosis, and acinar to ductal metaplasia (ADM) in pancreatic tissue were scored histologically and total macrophages, major histocompatibility complex (MHC)-II+ cells, M2 macrophages, T and B cells, neutrophils, apoptosis, and ADM were marked immunohistochemically and quantified by digital image analysis. Serum amylase had a peak at 12 hours, without differences between the sexes. In females, pancreatitis reached a peak at 12 hours with a fast recovery while, in males, the peak was delayed to day 2 with residual apoptosis still present. Macrophages were the main inflammatory cell population, followed by T cells, B cells and neutrophils, without differences between sexes. In males, CD206+ cells and apoptosis were higher at both days 2 and 7, and cytokeratin-19+ (CK19+) ADM was higher at day 7 compared with females. The results of this study revealed a faster onset and resolution of caerulein-induced AP in female mice compared with male mice, supporting a sex-dependent modulation of acute pancreatitis.

CIP2A inhibitors TD52 and Ethoxysanguinarine promote macrophage autophagy and alleviates acute pancreatitis by modulating the AKT-mTOR pathway

BACKGROUND

Acute pancreatitis (AP) is a prevalent and serious condition within the digestive system, with approximately 20 % to 30 % of cases advancing to severe acute pancreatitis (SAP). During the initial phases of SAP, macrophages are activated in response to the substantial amounts of acinar cell contents and damage-associated molecular patterns (DAMPs) resulting from acinar cell destruction. Subsequently, activated macrophages release a significant array of pro-inflammatory factors that exacerbate the progression of SAP. Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncogenic protein that is intimately linked to immune regulation. While the role of CIP2A in T-cell-mediated specific immune responses has been reported, its function and mechanism in macrophages, a component of non-specific immunity, have not been widely studied. This research fills this knowledge gap by elucidating the critical role of CIP2A in regulating macrophage autophagy and inflammation. This finding not only expands our understanding of CIP2A in immune modulation but also provides a new scientific basis and potential application prospects for targeting CIP2A in the treatment of AP.

METHODS

We established AP using a combination of palmitoleic acid with anhydrous ethanol or using caerulein alone. The effects of TD52 and Ethoxysanguinarine (Etho) on SAP were evaluated through serological, histopathological, and tissue inflammation observations. The effect of TD52 on macrophage activation in vitro was examined using primary macrophages (PMs) and RAW264.7 cells.

RESULTS

We found that TD52 and Etho inhibit CIP2A expression while reducing the levels of serum amylase, lipase, and inflammatory cytokines, thereby alleviating the pathological symptoms of SAP. Additionally, TD52 could reduce the infiltration of macrophages into pancreatic tissue. Therefore, we established a model of macrophage inflammatory response mimicking the pathophysiological process of AP and detected changes in inflammation, apoptosis, and autophagy through pre-treatment of macrophages with TD52. The results show that inhibiting CIP2A expression decreases the release of inflammatory cytokines and reduces apoptosis in macrophages. Further exploration revealed that TD52 promoted macrophage autophagy regulation and inhibited the AKT-mTOR pathway to modulate macrophage activation.

CONCLUSION

In summary, our findings indicate that TD52 and Etho can alleviate the severity of SAP. TD52 can block the AKT-mTOR pathway to promote macrophage autophagy, thereby improving SAP. Thus, CIP2A may serve as one of the molecular targets in SAP, highlighting its potential as a therapeutic option.

Biochanin-A co-crystal formulation improves bioavailability and ameliorates cerulein-induced pancreatitis by attenuating the inflammation

Co-crystallization of a therapeutic ingredient with an appropriate co-former is a powerful technique to augment the physicochemical and pharmacokinetic properties and the effectiveness of Active Pharmaceutical Ingredients (APIs). Biochanin A (BCA), a flavonoid with medicinal potential, is limited by poor solubility and low oral bioavailability. This study aimed to design and develop a novel BCA-nicotinamide cocrystal as BCC to enhance BCA's oral bioavailability and explore its therapeutic potential for ameliorating cerulein-induced acute pancreatitis (CIAP) by elucidating the target identification utilizing tissue/serum metabolite profiles. The cocrystal was designed by the supramolecular synthon approach and characterized by single-crystal X-ray diffraction that confirms a robust three-dimensional hydrogen-bonded network of BCA and Nicotinamide (NCT) in the crystal. FT-IR and DSC were used to analyze the cocrystal's intermolecular interactions and thermal behavior. BCC exhibited enhanced solubility and drug release compared to BCA alone, resulting in enhanced oral bioavailability and pancreatic tissue concentration. Comparing BCC to BCA in the CIAP model, BCC therapy remarkably reduced cerulein-induced pancreatitis, evidenced by significant reductions in inflammation, acinar cell atrophy, and amylase levels in pancreatic tissues. Further, the cocrystal formulation also down-regulated the oxidative stress markers, inflammatory cytokines and macrophage-related proteins. The study has identified distinct metabolomic signatures linked with AP with the help of Orbitrap Exploris mass spectrometry, which could pave the way for creating focused diagnostic tools for a better prognosis. In conclusion, these results offer new insights into exploring mechanistic pathways associated with specific biomarkers and underscore BCC cocrystal as a promising approach to enhance BCA's therapeutic potential.

Bone marrow mesenchymal stem cell-derived exosomal miR-181a-5p promotes M2 macrophage polarization to alleviate acute pancreatitis through ZEB2-mediated RACK1 ubiquitination

As a common digestive disease, acute pancreatitis (AP) often threatens the life of patients. Bone marrow mesenchymal stem cells (BMSCs) derived exosomes have exhibited some benefits for AP. However, the mechanism remains unclear and deserves to be further investigated. The characteristics of BMSCs-exosomes (BMSCs-Exos) were identified. The abundance of genes and proteins was evaluated using quantitative real-time PCR (RT-qPCR), western blot, enzyme-linked immunosorbent assay (ELISA) and IF assay. Cell apoptosis and CD206-positive cells were measured by flow cytometry. The interactions among miR-181a-5p, Zinc finger E-box binding homeobox 2 (ZEB2) and Receptor for Activated C Kinase 1 (RACK1) were verified using dual luciferase reporter assay, RNA immunoprecipitation (RIP), coimmunoprecipitation (Co-IP). BMSCs-Exos effectively improved AP injury through restraining AR42J cell apoptosis and promoting M2 macrophage polarization, which was realized due to BMSCs-Exos harboring an abundance of miR-181a-5p. Further experiments validated miR-181a-5p silenced ZEB2 and ZEB2 reduced RACK1 expression through mediating RACK1 ubiquitination. ZEB2 knockdown decreased AR42J cell apoptosis and induced M2 macrophage polarization to alleviate AP injury, whereas RACK1 downregulation abolished these phenomena. BMSCs-Exos harboring miR-181a-5p suppressed AR42J cell apoptosis and promoted M2 macrophage polarization to delay AP progression through ZEB2-mediated RACK1 ubiquitination.

Predictive analysis of osteoarthritis and chronic pancreatitis comorbidity: complications and risk factors

Background

The comorbidity of chronic pancreatitis (CP) in patients with osteoarthritis (OA) is insufficiently studied, and the reciprocal impact of these conditions remains poorly understood. This study aimed to investigate potential predictors for the development of CP in OA patients, as well as associated complications.

Methods

A cohort of 181 patients was categorized into four groups: a control group (n=30), patients with OA (n=68), patients with CP (n=31), and patients with OA and comorbid CP (n=52). All four groups had no statistical differences in age and gender. The study utilized the WOMAC index, Visual Analog Scale (VAS), Lequesne index, biochemical assays, and advanced statistical methods to assess joint status in OA patients with comorbid CP. It explored potential predictors of comorbidity development and associated complications.

Results

The study revealed that concurrent CP in OA exacerbates progression and contributes to malnutrition. Body Mass Index (BMI) emerged as a potential predictor for CP comorbidity development in OA patients. Factors such as the WOMAC total score, fecal elastase-1, C-reactive protein (CRP), ferritin, retinol, tocopherol, 25-hydroxyvitamin D3, and BMI were found to influence the development of comorbidity of CP in OA. Additionally, Gastrointestinal Symptom Rating Scale-Diarrhea Syndrome (GSRS-DS), Gastrointestinal Symptom Rating Scale-Constipation Syndrome (GSRS-CS), Qualitative Assessment of the Symptoms and Impact of Pancreatic Exocrine Insufficiency Domain A (PEI-Q-A), retinol, tocopherol, and iron were identified as potential predictors comorbidity CP with exocrine pancreatic insufficiency in OA patients.

Conclusion

The presence of CP in OA patients exacerbates disease progression and complications, necessitating further investigation.

DGA ameliorates severe acute pancreatitis through modulating macrophage pyroptosis

Severe acute pancreatitis (SAP) is an inflammatory disease with varying severity, ranging from mild local inflammation to severe systemic disease, with a high incidence rate and mortality. Current drug treatments are not ideal. Therefore, safer and more effective therapeutic drugs are urgently needed. 7α,14β-dihydroxy-ent-kaur-17-dimethylamino-3,15-dione DGA, a diterpenoid compound derivatized from glaucocalyxin A, exhibits anti-inflammatory activity. In this study, we demonstrated the therapeutic potential of DGA against SAP and elucidated the underlying mechanisms. Treatment with DGA markedly (1) inhibited death of RAW264.7 and J774a.1 cells induced by Nigericin and lipopolysaccharide, (2) alleviated edema, acinar cell vacuolation, necrosis, and inflammatory cell infiltration of pancreatic tissue in mice, and (3) inhibited the activity of serum lipase and the secretion of inflammatory factor IL-1β. DGA significantly reduced the protein expression of IL-1β and NLRP3 and inhibited the phosphorylation of NF-κB. However, DGA exhibited no inhibitory effect on the expression of caspase-1, gasdermin D (GSDMD), NF-κB, TNF-α, or apoptosis-associated speck-like protein (ASC) and on the cleavage of caspase-1 or GSDMD. Molecular docking simulation confirmed that DGA can bind to TLR4 and IL-1 receptor. In conclusion, DGA may effectively alleviate the symptoms of SAP in mice and macrophages by inhibiting the binding of TLR4 and IL-1 receptor to their ligands; therefore, DGA is a promising drug candidate for the treatment of patients with SAP.

The BRD4 Inhibitor I-BET-762 Reduces HO-1 Expression in Macrophages and the Pancreas of Mice

In pancreatic cancer, the tumor microenvironment (TME) accounts for up to 90% of the tumor mass. Pancreatitis, characterized by the increased infiltration of macrophages into the pancreas, is a known risk factor for pancreatic cancer. The NRF2 (nuclear factor erythroid 2-related factor 2) transcription factor regulates responses to oxidative stress and can promote cancer and chemoresistance. NRF2 also attenuates inflammation through the regulation of macrophage-specific genes. Heme oxygenase 1 (HO-1) is expressed by anti-inflammatory macrophages to degrade heme, and its expression is dependent on NRF2 translocation to the nucleus. In macrophages stimulated with conditioned media from pancreatic cancer cells, HO-1 protein levels increased, which correlated with higher NRF2 expression in the nuclear fraction. Significant differences in macrophage infiltration and HO-1 expression were detected in LSL-KrasG12D/+; Pdx-1-Cre (KC) mice, Nrf2 whole-body knockout (KO) mice and wildtype mice with pancreatitis. Since epigenetic modulation is a mechanism used by tumors to regulate the TME, using small molecules as epigenetic modulators to activate immune recognition is therapeutically desirable. When the bromodomain inhibitor I-BET-762 was used to treat macrophages or mice with pancreatitis, high levels of HO-1 were reduced. This study shows that bromodomain inhibitors can be used to prevent physiological responses to inflammation that promote tumorigenesis.

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.

Natural products with anti-tumorigenesis potential targeting macrophage

BACKGROUND

Inflammation is a risk factor for tumorigenesis. Macrophage, a subset of immune cells with high plasticity, plays a multifaceted role in this process. Natural products, which are bioactive compounds derived from traditional herbs or foods, have exhibited diverse effects on macrophages and tumorigenesis making them a valuable resource of drug discovery or optimization in tumor prevention.

PURPOSE

Provide a comprehensive overview of the various roles of macrophages in tumorigenesis, as well as the effects of natural products on tumorigenesis by modulating macrophage function.

METHODS

A thorough literature search spanning the past two decades was carried out using PubMed, Web of Science, Elsevier, and CNKI following the PRISMA guidelines. The search terms employed included "macrophage and tumorigenesis", "natural products, macrophages and tumorigenesis", "traditional Chinese medicine and tumorigenesis", "natural products and macrophage polarization", "macrophage and tumor related microenvironment", "macrophage and tumor signal pathway", "toxicity of natural products" and combinations thereof. Furthermore, certain articles are identified through the tracking of citations from other publications or by accessing the websites of relevant journals. Studies that meet the following criteria are excluded: (1) Articles not written in English or Chinese; (2) Full texts were not available; (3) Duplicate articles and irrelevant studies. The data collected was organized and summarized based on molecular mechanisms or compound structure.

RESULTS

This review elucidates the multifaceted effect of macrophages on tumorigenesis, encompassing process such as inflammation, angiogenesis, and tumor cell invasion by regulating metabolism, non-coding RNA, signal transduction and intercellular crosstalk. Natural products, including vitexin, ovatodiolide, ligustilide, and emodin, as well as herbal remedies, have demonstrated efficacy in modulating macrophage function, thereby attenuating tumorigenesis. These interventions mainly focus on mitigating the initial inflammatory response or modifying the inflammatory environment within the precancerous niche.

CONCLUSIONS

These mechanistic insights of macrophages in tumorigenesis offer valuable ideas for researchers. The identified natural products facilitate the selection of promising candidates for future cancer drug development.

Role of Interleukin 6 in Acute Pancreatitis: A Possible Marker for Disease Prognosis

Acute pancreatitis (AP) is a significant cause of morbidity, even in children, and is frequently associated with systemic manifestations. There are many cytokines involved in the inflammatory response characteristic of this disease. Interleukin 6 (IL-6) is one of the most important cytokines involved in AP, beginning from cellular injury and continuing to the systemic inflammatory response and distant organ involvement. IL-6 is a multifunctional cytokine that regulates acute-phase response and inflammation. It is produced by various cells and exerts its biological role on many cells through its high-affinity complex receptor. IL-6 has been investigated as a predicting maker for severe forms of AP. Many studies have validated the use of IL-6 serum levels in the first 48 h as a reliable marker for severe evolution and multisystemic involvement. Still, it has not been used in daily practice until now. This review discusses the main binding mechanisms by which IL-6 triggers cellular response and the AP pathogenetic mechanisms in which IL-6 is involved. We then emphasize the promising role of IL-6 as a prognostic marker, which could be added as a routine marker at admission in children with AP.

From pancreas to lungs: The role of immune cells in severe acute pancreatitis and acute lung injury

BACKGROUND

Severe acute pancreatitis (SAP) is a potentially lethal inflammatory pancreatitis condition that is usually linked to multiple organ failure. When it comes to SAP, the lung is the main organ that is frequently involved. Many SAP patients experience respiratory failure following an acute lung injury (ALI). Clinicians provide insufficient care for compounded ALI since the underlying pathophysiology is unknown. The mortality rate of SAP patients is severely impacted by it.

OBJECTIVE

The study aims to provide insight into immune cells, specifically their roles and modifications during SAP and ALI, through a comprehensive literature review. The emphasis is on immune cells as a therapeutic approach for treating SAP and ALI.

FINDINGS

Immune cells play an important role in the complicated pathophysiology ofSAP and ALI by maintaining the right balance of pro- and anti-inflammatory responses. Immunomodulatory drugs now in the market have low thepeutic efficacy because they selectively target one immune cell while ignoring immune cell interactions. Accurate management of dysregulated immune responses is necessary. A critical initial step is precisely characterizing the activity of the immune cells during SAP and ALI.

CONCLUSION

Given the increasing incidence of SAP, immunotherapy is emerging as a potential treatment option for these patients. Interactions among immune cells improve our understanding of the intricacy of concurrent ALI in SAP patients. Acquiring expertise in these domains will stimulate the development of innovative immunomodulation therapies that will improve the outlook for patients with SAP and ALI.

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.

Deletion of myeloid-specific Orai1 calcium channel does not affect pancreatic tissue damage in experimental acute pancreatitis

BACKGROUND

Store-operated Ca2+ entry (SOCE) mediated by ORAI1 channel plays a crucial role in acute pancreatitis (AP). Macrophage is an important regulator in amplifying pancreatic tissue damage, but little is known about the role of ORAI1 in macrophages. In this study, we examined the effects of macrophage-specific ORAI1 on pancreatic tissue damage in AP.

METHOD

Myeloid-specific Orai1 deficient mice was generated by crossing a LysM-Cre mouse line with Orai1f/f mice. Bone marrow-derived macrophages (BMDMs) were isolated, cultured, and stimulated to induce M1 or M2 macrophage polarization. Intracellular Ca2+ signals were measured by time-lapse confocal microscope imaging, with a Ca2+ indicator (Fluo 4). Experimental AP was induced by hourly intraperitoneal injections of caerulein or retrograde biliopancreatic infusion of sodium taurocholate. Pancreatic tissue damage was assessed by histopathological scoring and immunostaining. Sepsis was induced by intraperitoneal injection of lipopolysaccharide; organ damage and serum pro-inflammatory cytokines were measured.

RESULT

Myeloid-specific Orai1 deletion exhibited minimal effect on SOCE in M0 macrophages and promoted M2 macrophage polarization ex vivo. Myeloid-specific Orai1 deletion did not affect pancreatic tissue damage, nor neutrophil or macrophage infiltration in two models of AP. Similarly, myeloid-specific Orai1 deletion did not influence overall survival rate in a model of sepsis, nor lung, kidney, and liver damage; while serum pro-inflammatory cytokines, including IL-6, TNF-α, and IL-1β were higher in Orai1ΔLysM mice, but were largely reduced in mice with Orai1 inhibitor.

CONCLUSION

Our data suggest that ORAI1 may not be a predominant SOCE channel in macrophages and play a limited role in mediating pancreatic tissue damage in AP.

The Pivotal Role of Macrophages in the Pathogenesis of Pancreatic Diseases

The pancreas is an organ with both exocrine and endocrine functions, comprising a highly organized and complex tissue microenvironment composed of diverse cellular and non-cellular components. The impairment of microenvironmental homeostasis, mediated by the dysregulation of cell-to-cell crosstalk, can lead to pancreatic diseases such as pancreatitis, diabetes, and pancreatic cancer. Macrophages, key immune effector cells, can dynamically modulate their polarization status between pro-inflammatory (M1) and anti-inflammatory (M2) modes, critically influencing the homeostasis of the pancreatic microenvironment and thus playing a pivotal role in the pathogenesis of the pancreatic disease. This review aims to summarize current findings and provide detailed mechanistic insights into how alterations mediated by macrophage polarization contribute to the pathogenesis of pancreatic disorders. By analyzing current research comprehensively, this article endeavors to deepen our mechanistic understanding of regulatory molecules that affect macrophage polarity and the intricate crosstalk that regulates pancreatic function within the microenvironment, thereby facilitating the development of innovative therapeutic strategies that target perturbations in the pancreatic microenvironment.

Circulating immune signatures in chronic pancreatitis with and without preceding acute pancreatitis: A pilot study

OBJECTIVE

To investigate profiles of circulating immune signatures in healthy controls and chronic pancreatitis patients (CP) with and without a preceding history of acute pancreatitis (AP).

METHODS

We performed a phase 1, cross-sectional analysis of prospectively collected serum samples from the PROspective Evaluation of Chronic Pancreatitis for EpidEmiologic and Translation StuDies (PROCEED) study. All samples were collected during a clinically quiescent phase. CP subjects were categorized into two subgroups based on preceding episode(s) of AP. Healthy controls were included for comparison. Blinded samples were analyzed using an 80-plex Luminex assay of cytokines, chemokines, and adhesion molecules. Group and pairwise comparisons of analytes were performed between the subgroups.

RESULTS

In total, 133 patients with CP (111 with AP and 22 without AP) and 50 healthy controls were included. Among the 80 analytes studied, CP patients with a history of AP had significantly higher serum levels of pro-inflammatory cytokines (interleukin (IL)-6, IL-8, IL-1 receptor antagonist, IL-15) and chemokines (Cutaneous T-Cell Attracting Chemokine (CTACK), Monokine induced Gamma Interferon (MIG), Macrophage-derived Chemokine (MDC), Monocyte Chemoattractant Protein-1 (MCP-1)) compared to CP without preceding AP and controls. In contrast, CP patients without AP had immune profiles characterized by low systemic inflammation and downregulation of anti-inflammatory mediators, including IL-10.

CONCLUSION

CP patients with a preceding history of AP have signs of systemic inflammatory activity even during a clinically quiescent phase. In contrast, CP patients without a history of AP have low systemic inflammatory activity. These findings suggest the presence of two immunologically diverse subtypes of CP.

Bioinformatics and Machine Learning Methods Identified MGST1 and QPCT as Novel Biomarkers for Severe Acute Pancreatitis

Severe acute pancreatitis (SAP) is a life-threatening gastrointestinal emergency. The study aimed to identify biomarkers and investigate molecular mechanisms of SAP. The GSE194331 dataset from GEO database was analyzed using bioinformatics. Differentially expressed genes (DEGs) associated with SAP were identified, and a protein-protein interaction network (PPI) was constructed. Machine learning algorithms were used to determine potential biomarkers. Gene set enrichment analysis (GSEA) explored molecular mechanisms. Immune cell infiltration were analyzed, and correlation between biomarker expression and immune cell infiltration was calculated. A competing endogenous RNA network (ceRNA) was constructed, and biomarker expression levels were quantified in clinical samples using RT-PCR. 1101 DEGs were found, with two modules most relevant to SAP. Potential biomarkers in peripheral blood samples were identified as glutathione S-transferase 1 (MGST1) and glutamyl peptidyltransferase (QPCT). GSEA revealed their association with immunoglobulin regulation, with QPCT potentially linked to pancreatic cancer development. Correlation between biomarkers and immune cell infiltration was demonstrated. A ceRNA network consisting of 39 nodes and 41 edges was constructed. Elevated expression levels of MGST1 and QPCT were verified in clinical samples. In conclusion, peripheral blood MGST1 and QPCT show promise as SAP biomarkers for diagnosis, providing targets for therapeutic intervention and contributing to SAP understanding.

Inhibition of Pck1 in intestinal epithelial cells alleviates acute pancreatitis via modulating intestinal homeostasis

Intestinal barrier dysfunction usually occurred in acute pancreatitis (AP) but the mechanism remains unclear. In this study, RNA sequencing of ileum in L-arginine-induced AP mice demonstrated that phosphoenolpyruvate kinase 1 (Pck1) was significantly up-regulated. Increased Pck1 expression in intestinal epithelial cells (IECs) was further validated in ileum of AP mice and duodenum of AP patients. In AP mice, level of Pck1 was positively correlated with pancreatic and ileal histopathological scores, serum amylase activity, and intestinal permeability (serum diamine oxidase (DAO), D-lactate, and endotoxin). In AP patients, level of Pck1 had a positive correlation with Ranson scores, white blood cell count and C-reactive protein. Inhibition of Pck1 by 3-Mercaptopicolinic acid hydrochloride (3-MPA) alleviated pancreatic and ileal injuries in AP mice. AP + 3-MPA mice showed improved intestinal permeability, including less epithelial apoptosis, increased tight junction proteins (TJPs) expression, decreased serum DAO, D-lactate, endotoxin, and FITC-Dextran levels, and reduced bacteria translocation. Lysozyme secreted by Paneth cells and mucin2 (MUC2) secretion in goblet cells were also partly restored in AP + 3-MPA mice. Meanwhile, inhibition of Pck1 improved intestinal immune response during AP, including elevation of M2/M1 macrophages ratio and secretory immunoglobulin A (sIgA) and reduction in neutrophils infiltration. In vitro, administration of 3-MPA dramatically ameliorated inflammation and injuries of epithelial cells in enteroids treated by LPS. In conclusion, inhibition of Pck1 in IECs might alleviate AP via modulating intestinal homeostasis.

Mitochondrial (mt)DNA-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling promotes pyroptosis of macrophages via interferon regulatory factor (IRF)7/IRF3 activation to aggravate lung injury during severe acute pancreatitis

BACKGROUND

Macrophage proinflammatory activation contributes to the pathology of severe acute pancreatitis (SAP) and, simultaneously, macrophage functional changes, and increased pyroptosis/necrosis can further exacerbate the cellular immune suppression during the process of SAP, where cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) plays an important role. However, the function and mechanism of cGAS-STING in SAP-induced lung injury (LI) remains unknown.

METHODS

Lipopolysaccharide (LPS) was combined with caerulein-induced SAP in wild type, cGAS -/- and sting -/- mice. Primary macrophages were extracted via bronchoalveolar lavage and peritoneal lavage. Ana-1 cells were pretreated with LPS and stimulated with nigericin sodium salt to induce pyroptosis in vitro.

RESULTS

SAP triggered NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation-mediated pyroptosis of alveolar and peritoneal macrophages in mouse model. Knockout of cGAS/STING could ameliorate NLRP3 activation and macrophage pyroptosis. In addition, mitochondrial (mt)DNA released from damaged mitochondria further induced macrophage STING activation in a cGAS- and dose-dependent manner. Upregulated STING signal can promote NLRP3 inflammasome-mediated macrophage pyroptosis and increase serum interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α levels and, thus, exacerbate SAP-associated LI (SAP-ALI). Downstream molecules of STING, IRF7, and IRF3 connect the mtDNA-cGAS-STING axis and the NLRP3-pyroptosis axis.

CONCLUSIONS

Negative regulation of any molecule in the mtDNA-cGAS-STING-IRF7/IRF3 pathway can affect the activation of NLRP3 inflammasomes, thereby reducing macrophage pyroptosis and improving SAP-ALI in mouse model.

The Pathogenesis of Pancreatitis and the Role of Autophagy

The pathogenesis of acute and chronic pancreatitis has recently evolved as new findings demonstrate a complex mechanism operating through various pathways. In this review, the current evidence indicating that several mechanisms act in concert to induce and perpetuate pancreatitis were presented. As autophagy is now considered a fundamental mechanism in the pathophysiology of both acute and chronic pancreatitis, the fundamentals of the autophagy pathway were discussed to allow for a better understanding of the pathophysiological mechanisms of pancreatitis. The various aspects of pathogenesis, including trypsinogen activation, ER stress and mitochondrial dysfunction, the implications of inflammation, and macrophage involvement in innate immunity, as well as the significance of pancreatic stellate cells in the development of fibrosis, were also analyzed. Recent findings on exosomes and the miRNA regulatory role were also presented. Finally, the role of autophagy in the protection and aggravation of pancreatitis and possible therapeutic implications were reviewed.

Novel therapeutics to treat chronic pancreatitis: targeting pancreatic stellate cells and macrophages

INTRODUCTION

Chronic pancreatitis (CP) is a persistent, recurrent, and progressive disorder that is characterized by chronic inflammation and irreversible fibrosis of the pancreas. It is associated with severe morbidity, resulting in intense abdominal pain, diabetes, exocrine and endocrine dysfunction, and an increased risk of pancreatic cancer. The etiological factors are diverse and the major risk factors include smoking, chronic alcoholism, as well as other environmental and genetic factors. The treatment and management of CP is challenging, and no definitive curative therapy is currently available.

AREAS COVERED

This review paper aims to provide an overview of the different cell types in the pancreas that is known to mediate disease progression and outline potential novel therapeutic approaches and drug targets that may be effective in treating and managing CP. The information presented in this review was obtained by conducting a NCBI PubMed database search, using relevant keywords.

EXPERT OPINION

In recent years, there has been an increased interest in the development of novel therapeutics for CP. A collaborative multi-disciplinary approach coupled with a consistent funding for research can expedite progress of translating the findings from bench to bedside.

Pirfenidone alleviates chronic pancreatitis via suppressing the activation of pancreatic stellate cells and the M1 polarization of macrophages

In the realm of fibroinflammatory conditions, chronic pancreatitis (CP) stands out as a particularly challenging ailment, lacking a dedicated, approved treatment. The potential of Pirfenidone (PFD), a drug originally used for treating idiopathic pulmonary fibrosis (IPF), in addressing CP's fibrotic aspects has sparked new interest. This investigation focused on the role of PFD in diminishing fibrosis and immune response in CP, using a mouse model induced by caerulein. The research extended to in vitro studies examining the influence of PFD on pancreatic stellate cells' (PSCs) behavior and the polarization of macrophages into M1 and M2 types. Advanced techniques like RNA sequencing and comprehensive data analyses were employed to decode the molecular interactions of PFD with PSCs. Supplementary experiments using techniques such as quantitative real-time PCR, western blotting, and immunofluorescence were also implemented. Results showed a notable reduction in pancreatic damage in PFD-treated mice, manifested through decreased acinar cell atrophy, lower collagen deposition, and a reduction in macrophage presence. Further investigation revealed PFD's capacity to hinder PSCs' migration, growth, and activation, alongside a reduction in the production and secretion of extracellular matrix proteins. This effect is primarily achieved by interfering with signaling pathways such as TGF-β/Smad, Wnt/β-catenin, and JAK/STAT. Additionally, PFD selectively hampers M1 macrophage polarization through the STAT3 pathway, without impacting M2 polarization. These outcomes highlight PFD's dual mechanism in moderating PSC activity and M1 macrophage polarization, positioning it as a promising candidate for CP therapy.

Bioinformatics analyses of infiltrating immune cell participation on pancreatic ductal adenocarcinoma progression and in vivo experiment of the therapeutic effect of Shuangshen granules

ETHNOPHARMACOLOGICAL RELEVANCE

Shuangshen granules (SSG), a nationally patented Chinese medicinal formula, including Panax quinquefolium L., Panax notoginseng (Burkill) F. H. Chen, and Cordyceps sinensis (Berk.) Sacc., has demonstrated remarkable therapeutic effects on pancreatic cancer in clinical treatment for nearly 10 years. Previous pharmacological researches have found that its main components, including ginsenosides and cordycepin have anticancer or preventive effects on pancreatic ductal adenocarcinoma (PDAC), which may be associated with immune metabolism. However, the underlying pharmacological mechanism of SSG in the truncation effect of PDAC progression is still unclear.

AIM OF THE STUDY

To comprehensively understand the infiltrating immune cells during the different stages of the PDAC development chain and search for immune-related biomarkers that could potentially serve as drug targets through bioinformatic analysis. Meanwhile, the truncation effect of SSG on PDAC progression was also investigated.

MATERIALS AND METHODS

The gene expression profiles at different PDAC developmental stages, including normal pancreas, pancreatic intraepithelial neoplasia (PanIN), and PDAC, were retrieved from the GEO database. The GEO2R tool was used to identify differentially expressed genes among the three groups. Functional enrichment analysis was performed with the GSEA software and Metascape platform. The CIBERSORT algorithm evaluated immune cell infiltration in the three groups, and immune-related biomarkers were identified. Correlation analysis was employed to examine the association between immune cells and the biomarkers. One of these biomarkers was selected for immunohistochemistry validation in human samples. Lastly, the effectiveness of SSG against PDAC progression and the influence on the selected biomarker were validated in vivo. The underlying pharmacological mechanisms were also explored.

RESULTS

One dataset was obtained, where the functional enrichment of DEGs primarily involved immune effector processes and cytokine production of immune cells. The differential immune cells reflected during the progression from PanIN to PDAC were B memory cells, monocytes, M2 macrophages, and activated dendritic cells. The upregulation of ACTA2 was closely associated with M2 macrophage regulation. The immunohistochemistry on human samples validated significant differences in ACTA2 expression levels as the PDAC progressed. Moreover, animal experiments revealed that the national patented drug SSG ameliorated the pathological changes, decreased the expression of ACTA2 and its functional protein α-smooth muscle actin during PDAC progression. The underlying pharmacological mechanism was related to the regulation of macrophage polarization and downregulation of TGF-β/Smad signaling pathway.

CONCLUSIONS

The immunosuppressive environment changes during the PDAC progression. ACTA2 is a potential immuned-target for drug prevention of PDAC, while SSG could be a promising drug candidate.

Toll-like receptor 4 in pancreatic damage and immune infiltration in acute pancreatitis

Acute pancreatitis is a complex inflammatory disease resulting in extreme pain and can result in significant morbidity and mortality. It can be caused by several factors ranging from genetics, alcohol use, gall stones, and ductal obstruction caused by calcification or neutrophil extracellular traps. Acute pancreatitis is also characterized by immune cell infiltration of neutrophils and M1 macrophages. Toll-like receptor 4 (TLR4) is a pattern recognition receptor that has been noted to respond to endogenous ligands such as high mobility group box 1 (HMGB1) protein and or exogenous ligands such as lipopolysaccharide both of which can be present during the progression of acute pancreatitis. This receptor can be found on a variety of cell types from endothelial cells to resident and infiltrating immune cells leading to production of pro-inflammatory cytokines as well as immune cell activation and maturation resulting in the furthering of pancreatic damage during acute pancreatitis. In this review we will address the various mechanisms mediated by TLR4 in the advancement of acute pancreatitis and how targeting this receptor could lead to improved outcomes for patients suffering from this condition.

Gastrodin ameliorates acute pancreatitis by modulating macrophage inflammation cascade via inhibition the p38/NF-κB pathway

Acute pancreatitis (AP) is a prevalent, destructive, non-infectious pancreatic inflammatory disease, which is usually accompanied with systemic manifestations and poor prognosis. Gastrodin (4-hydroxybenzyl alcohol 4-O-β-d-glucopyranoside) has ideal anti-inflammatory effects in various inflammatory diseases. However, its potential effects on AP had not been studied. In this study, serum biochemistry, H&E staining, immunohistochemistry, immunofluorescence, western blot, real-time quantitative PCR (RT-qPCR) were performed to investigate the effects of Gastrodin on caerulein-induced AP pancreatic acinar injury model in vivo and lipopolysaccharide (LPS) induced M1 phenotype macrophage model in vitro. Our results showed that Gastrodin treatment could significantly reduce the levels of serum amylase and serum lipase while improving pancreatic pathological morphology. Additionally, it decreased secretion of inflammatory cytokines and chemokines, and inhibited the levels of p-p38/p38, p-IκB/IκB as well as p-NF-κB p-p65/NF-κB p65. Overall our findings suggested that Gastrodin might be a promising therapeutic option for patients with AP by attenuating inflammation through inhibition of the p38/NF-κB pathway mediated macrophage cascade.

Moluodan promotes DSS-induced intestinal inflammation involving the reprogram of macrophage function and polarization

ETHNOPHARMACOLOGICAL RELEVANCE

Moluodan (MLD) is a traditional Chinese medicine that is composed of 18 herbal medicines based on traditional Chinese medicine theory and practice. It has long been used in treating chronic gastritis and its components were traditionally used in dealing with intestinal inflammation. However, its specific pharmacological mechanism is still unclear.

AIM OF THE STUDY

The upper and lower digestive tract diseases are correlated. In clinical practice, some chronic gastritis patients are also accompanied by intestinal inflammation. Due to the unclear pharmacological mechanism of MLD and its effect on intestinal inflammation, there is doubt whether MLD is still suitable for this type of patient. Therefore, this study aims to elucidate the pharmacological mechanism of MLD and identify its effect in the mouse model of intestinal inflammation.

MATERIALS AND METHODS

Mice intestinal inflammation model was induced by 2.5% dextran sulfate sodium (DSS). The mice were given different concentrations of MLD via oral gavage (0.25, 0.5 g/kg b.w.). Pharmacodynamic indicators were assessed including body weight, colon length, disease activity index (DAI), bloody stool score, inflammatory factors, histological change, etc. RAW264.7 macrophage cells were used for in vitro experiments that illuminated the role of MLD in reprogramming macrophage function and polarization. RT-qPCR and western blots were performed to measure the mRNA and protein levels of macrophage polarization marker and effector molecules. The functions of polarized macrophages were tested using ROS detection probes, Edu assay and wound healing assay.

RESULTS

The administration of MLD exhibited obvious hemostatic effects, while unexpectedly accentuating various aspects of the DSS-induced intestinal inflammation in mice, including increased body weight loss and colon shortening, elevated disease activity index, and intensified colonic tissue damage. Additionally, MLD treatment induced more severe inflammatory cell infiltration and higher proinflammatory cytokines expression in colon tissue. Further results showed that MLD promoted M1 macrophage polarization and stimulated its proinflammatory cytokines expression, while only slightly affecting the function of M2 macrophage. Western blot analysis revealed that MLD induced the phosphorylation of AKT and NF-κB. The polarization of M1 macrophages induced by MLD was inhibited by either an Akt inhibitor or a NF-κB inhibitor.

CONCLUSIONS

Although MLD has an obvious hemostatic effect, it generally promoted the severity of DSS-induced colitis in mice by facilitating macrophage polarization toward the M1 phenotype through the AKT/NF-κB pathway. Our study suggested that MLD may not be suitable for colitis, especially during the acute inflammation stage.

Nicotinamide adenine dinucleotide phosphate oxidase in pancreatic diseases: Mechanisms and future perspectives

Pancreatitis and pancreatic cancer (PC) stand as the most worrisome ailments affecting the pancreas. Researchers have dedicated efforts to unraveling the mechanisms underlying these diseases, yet their true nature continues to elude their grasp. Within this realm, oxidative stress is often believed to play a causal and contributory role in the development of pancreatitis and PC. Excessive accumulation of reactive oxygen species (ROS) can cause oxidative stress, and the key enzyme responsible for inducing ROS production in cells is nicotinamide adenine dinucleotide phosphate hydrogen oxides (NOX). NOX contribute to pancreatic fibrosis and inflammation by generating ROS that injure acinar cells, activate pancreatic stellate cells, and mediate macrophage polarization. Excessive ROS production occurs during malignant transformation and pancreatic carcinogenesis, creating an oxidative microenvironment that can cause abnormal apoptosis, epithelial to mesenchymal transition and genomic instability. Therefore, understanding the role of NOX in pancreatic diseases contributes to a more in-depth exploration of the exact pathogenesis of these diseases. In this review, we aim to summarize the potential roles of NOX and its mechanism in pancreatic disorders, aiming to provide novel insights into understanding the mechanisms underlying these diseases.

Tectoridin alleviates caerulein-induced severe acute pancreatitis by targeting ERK2 to promote macrophage M2 polarization

Severe acute pancreatitis (SAP) is an inflammatory disease of the pancreas with a high mortality rate. Macrophages play a crucial role in the pathogenesis of pancreatitis. Tectoridin (Tec) is a highly active isoflavone with anti-inflammatory pharmacological activity. However, the role of Tec in the SAP process is not known. The purpose of this study was to investigate the therapeutic effect and potential mechanism of Tec on SAP. To establish SAP mice by intraperitoneal injection of caerulein and Lipopolysaccharide (LPS), the role of Tec in the course of SAP was investigated based on histopathology, biochemical indicators of amylase and lipase and inflammatory factors. The relationship between Tec and macrophage polarization was verified by immunofluorescence, real-time quantitative PCR and Western blot analysis. We then further predicted the possible targets and signal pathways of action of Tec by network pharmacology and molecular docking, and validated them by in vivo and in vitro. In this study, we demonstrated that Tec significantly reduced pancreatic injury in SAP mice, and decreased serum levels of amylase and lipase. The immunofluorescence and Western blot analysis showed that Tec promoted macrophage M2 polarization. Network pharmacology and molecular docking predicted that Tec may target ERK2 for the treatment of SAP, and in vivo and in vitro experiments proved that Tec inhibited the ERK MAPK signal pathway. In summary, Tec can target ERK2, promote macrophage M2 polarization and attenuate pancreatic injury, Tec may be a potential drug for the treatment of SAP.

Ferritin and Ferritin-to-Hemoglobin Ratio as Promising Prognostic Biomarkers of Severity in Acute Pancreatitis-A Cohort Study

BACKGROUND

Acute pancreatitis is an inflammation of the pancreas with variable outcomes depending on its severity. Multiple systems of prediction have been proposed, each with variable specificity and sensitivity and with uneven clinical use. Ferritin is a versatile protein associated with various acute and chronic conditions.

AIMS

In our study, we aimed to assess the association of serum ferritin and the ferritin-to-hemoglobin ratio (FHR) with the severity of acute pancreatitis.

METHODS

A retrospective study was conducted in our hospital from January 2020 to September 2022 and included 116 patients with acute pancreatitis (graded according to the revised Atlanta classification). Serum ferritin and FHR were determined next to established laboratory parameters in the first 24 h following admission (hematological parameters, amylase, lipase, C-reactive protein, D-dimers, lactate dehydrogenase). We performed a receiver operating characteristic curve analysis for potential predictors. Also, we made correlations and conducted univariate and multivariate analyses for all potential severity biomarkers.

RESULTS

The median values of serum ferritin and FHR differed significantly between patients with severe acute pancreatitis and mild cases (serum ferritin: 352.40 vs. 197.35 ng/mL, p = 0.011; FHR: 23.73 vs. 13.74, p = 0.002) and between patients with organ failure and those without organ failure (serum ferritin: 613.45 vs. 279.65 ng/mL, p = 0.000; FHR: 48.12 vs. 18.64, p = 0.000). The medians of the serum ferritin and FHR levels were significantly higher in non-survivors compared with survivors (serum ferritin: 717.71 vs. 305.67 ng/mL, p = 0.013; FHR: 52.73 vs. 19.58, p = 0.016). Serum ferritin and FHR were good predictors for organ failure and mortality, next to D-dimers and procalcitonin (AUC > 0.753 for organ failure and AUC > 0.794 for mortality). In univariate regression analysis, serum ferritin and FHR were independent variables for moderate-severe forms of acute pancreatitis. Still, adjusting the multivariate analysis, only FHR remained a significant predictor. The cut-offs for serum ferritin and FHR for predicting organ failure were 437.81 ng/mL (sensitivity, 71%; specificity, 75%) and 45.63 (sensitivity, 61%; specificity, 88%), and those for mortality during hospitalization were 516 ng/mL (sensitivity, 83%; specificity, 74%) and 51.58 (sensitivity, 66%; specificity, 86%).

CONCLUSIONS

Serum ferritin and the ferritin-to-hemoglobin ratio stood out in this study as valuable and accessible predictors of disease severity in the early assessment of acute pancreatitis, next to established severity serum markers (CRP, fibrinogen, D-dimers).

Macrophage-derived exosomal miRNA-141 triggers endothelial cell pyroptosis by targeting NLRP3 to accelerate sepsis progression

Sepsis, critical condition marked by severe organ dysfunction from uncontrolled infection, involves the endothelium significantly. Macrophages, through paracrine actions, play a vital role in sepsis, but their mechanisms in sepsis pathogenesis remain elusive. Objective: We aimed to explore how macrophage-derived exosomes with low miR-141 expression promote pyroptosis in endothelial cells (ECs). Exosomes from THP-1 cell supernatant were isolated and characterized. The effects of miR-141 mimic/inhibitor on apoptosis, proliferation, and invasion of Human Umbilical Vein Endothelial Cells (HUVECs) were assessed using flow cytometry, CCK-8, and transwell assays. Key pyroptosis-related proteins, including caspase-1, IL-18, IL-1β, NLR Family Pyrin Domain Containing 3 (NLRP3), ASC, and cleaved-GSDMD, were analyzed via Western blot. The interaction between miR-141 and NLRP3 was studied using RNAhybrid v2.2 and dual-Luciferase reporter assays. The mRNA and protein level of NLRP3 after exosomal miR-141 inhibitor treatment was detected by qPCR and Western blot, respectively. Exosomes were successfully isolated. miR-141 mimic reduced cell death and pyroptosis-related protein expression in HUVECs, while the inhibitor had opposite effects, increasing cell death, and enhancing pyroptosis protein expression. Additionally, macrophage-derived exosomal miR-141 inhibitor increased cell death and pyroptosis-related proteins in HUVECs. miR-141 inhibits NLRP3 transcription. Macrophages facilitate sepsis progression by secreting miR-141 decreased exosomes to activate NLRP3-mediated pyroptosis in ECs, which could be a potentially valuable target of sepsis therapy.

Long non-coding RNA MM2P suppresses M1-polarized macrophages-mediated excessive inflammation to prevent sodium taurocholate-induced acute pancreatitis by blocking SHP2-mediated STAT3 dephosphorylation

M1 macrophage-mediated excessive inflammatory response plays a key role in the onset and progression of acute pancreatitis (AP), and this study aimed to investigate the role and underlying mechanisms by which the macrophage polarization-related long noncoding RNA (lncRNA) MM2P participated in the regulation of AP progression. By performing quantitative reverse-transcription PCR (qRT-PCR) assay, lncRNA MM2P was found to be downregulated in both sodium taurocholate-induced AP model mice tissues and lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and gain-of-function experiments confirmed that overexpression of lncRNA MM2P counteracted inflammatory responses, reduced macrophage infiltration and facilitated M1-to-M2 transformation of macrophages to ameliorate AP development in vitro and in vivo. Further mechanical experiments revealed that lncRNA MM2P inhibited Src homology 2 containing protein tyrosine phosphatase 2 (SHP2)-mediated signal transducer and activator of transcription 3 (STAT3) dephosphorylation to activate the STAT3 signaling, and silencing of SHP2 suppressed M1 type skewing in LPS-induced RAW264.7 cells. Interestingly, our rescuing experiments verified that lncRNA MM2P-induced suppressing effects on M1-polarization of LPS-treated RAW264.7 cells were abrogated by co-treating cells with STAT3 inhibitor stattic. Collectively, our data for the first time revealed that lncRNA MM2P suppressed M1-polarized macrophages to attenuate the progression of sodium taurocholate-induced AP, and lncRNA MM2P might be an ideal biomarker for AP diagnosis and treatment.

Mechanotransductive receptor Piezo1 as a promising target in the treatment of fibrosis diseases

Fibrosis could happen in every organ, leading to organic malfunction and even organ failure, which poses a serious threat to global health. Early treatment of fibrosis has been reported to be the turning point, therefore, exploring potential correlates in the pathogenesis of fibrosis and how to reverse fibrosis has become a pressing issue. As a mechanism-sensitive cationic calcium channel, Piezo1 turns on in response to changes in the lipid bilayer of the plasma membrane. Piezo1 exerts multiple biological roles, including inhibition of inflammation, cytoskeletal stabilization, epithelial-mesenchymal transition, stromal stiffness, and immune cell mechanotransduction, interestingly enough. These processes are closely associated with the development of fibrotic diseases. Recent studies have shown that deletion or knockdown of Piezo1 attenuates the onset of fibrosis. Therefore, in this paper we comprehensively describe the biology of this gene, focusing on its potential relevance in pulmonary fibrosis, renal fibrosis, pancreatic fibrosis, and cardiac fibrosis diseases, except for the role of drugs (agonists), increased intracellular calcium and mechanical stress using this gene in alleviating fibrosis.

The Role and Potential Regulatory Mechanism of STING Modulated Macrophage Apoptosis and Differentiation in Severe Acute Pancreatitis-Associated Lung Injury

This study aims to investigate the role of STING in promoting macrophage apoptosis and regulating macrophage polarization in severe acute pancreatitis (SAP)-associated lung injury in vitro and in vivo. A murine model was established by intraperitoneal injection of caerulein and lipopolysaccharide (LPS). Meanwhile, ANA-1 cells were stimulated with LPS to induce apoptosis in vitro. More primary alveolar macrophages underwent apoptosis and M1 macrophage polarization in the SAP group compared with the control group, which was reversed by inhibiting STING. When ANA-1 cells were induced into M2-type macrophages, the reduction of M1 macrophage markers was accompanied by a decrease of LPS-induced apoptosis. Finally, the inhibitory effect of C-176 on STING ameliorates lung injury and inflammation by adjusting macrophage polarization and rescuing apoptosis. Therefore, inhibiting STING could be a new therapeutic strategy for treating acute pancreatitis-associated lung injury.

Recurrent chronic pancreatitis with intractable pancreatolithiasis

Due to low incidence rate of pancreatic duct stones，Authoritative consensus has not been reached regarding therapeutic choices in clinical practice. This article reports the treatment of a young woman with chronic pancreatitis complicated with refractory multiple pancreatic duct stones, which provides clinical experience for treatment and provides a new way to study the pathogenesis of chronic pancreatitis complicated with pancreatic duct stones.