Anisodamine alleviates lipopolysaccharide-induced pancreatic acinar cell injury through NLRP3 inflammasome and NF-κB signaling pathway

Activation of Nrf2/ARE pathway by Anisodamine (654-2) for Inhibition of cellular aging and alleviation of Radiation-Induced lung injury

BACKGROUND

Radiation-induced lung injury (RILI) is a common side effect of thoracic tumor radiotherapy, including early-stage radiation-induced lung injury (RP) and late-stage radiation-induced pulmonary fibrosis (RIPF). Currently, it is urgently needed to clarify the pathogenesis of RILI and find safe and effective RILI treatment methods. Irradiation causes DNA damage and oxidative stress in tissues and cells, induces cellular senescence, and promotes the occurrence and development of RILI. In recent years, Anisodamine (654-2) has shown potential therapeutic value in acute lung injury, acute kidney injury, chlamydial pneumonia, and COVID-19. However, there is currently no research on the mechanism of 654-2-mediated cellular senescence and its preventive and therapeutic effects on RILI.

PURPOSE

This study aimed to investigate the protective effect and mechanism of 654-2 on X-ray-induced RILI.

METHODS

In vivo experiments involved a mouse RILI model with 18 Gy X-ray irradiation. Mice were divided into control, model, medication (control + 654-2), and treatment (model + 654-2) groups. And mice in medication and treatment groups were intraperitoneal injection of 5 mg/kg 654-2 every other day until being sacrificed at week 6. In vitro experiments used MLE-12 cells irradiated with 16 Gy and divided into control, model, and model + 654-2（2 μM and 10 μM） groups. Various assays were performed to evaluate lung tissue morphology, fibrosis, apoptosis, cytokine expression, cellular senescence, protein expression, and antioxidant capacity.

RESULTS

654-2 mitigated pulmonary pathological damage, inflammation, DNA damage, cellular senescence, and apoptosis in RILI mice and MLE-12 cells. It restored epithelial cell proliferation ability and enhanced antioxidant capacity. Additionally, 654-2 activated the Nrf2/ARE pathway, increased Nrf2 phosphorylation, and upregulated antioxidant gene expression. Inhibition of Nrf2 reversed the effects of 654-2 on ROS production, antioxidant capacity, and cell senescence.

CONCLUSION

654-2 can activate the Nrf2/ARE pathway, enhance cellular antioxidant capacity, and inhibit cellular senescence, thereby exerting a protective effect against RILI.

Research Progress on Natural Small-Molecule Compounds for the Prevention and Treatment of Sepsis

Sepsis is a serious disease with high mortality and has been a hot research topic in medical research in recent years. With the continuous reporting of in-depth research on the pathological mechanisms of sepsis, various compounds have been developed to prevent and treat sepsis. Natural small-molecule compounds play vital roles in the prevention and treatment of sepsis; for example, compounds such as resveratrol, emodin, salidroside, ginsenoside, and others can modulate signaling through the NF-κB, STAT3, STAT1, PI3K, and other pathways to relieve the inflammatory response, immunosuppression, and organ failure caused by sepsis. Here, we discuss the functions and mechanisms of natural small-molecule compounds in preventing and treating sepsis. This review will lay the theoretical foundation for discovering new natural small-molecule compounds that can potentially prevent and treat sepsis.

Acinar cells and the development of pancreatic fibrosis

Pancreatic fibrosis is caused by excessive deposition of extracellular matrixes of collagen and fibronectin in the pancreatic tissue as a result of repeated injury often seen in patients with chronic pancreatic diseases. The most common causative conditions include inborn errors of metabolism, chemical toxicity and autoimmune disorders. Its pathophysiology is highly complex, including acinar cell injury, acinar stress response, duct dysfunction, pancreatic stellate cell activation, and persistent inflammatory response. However, the specific mechanism remains to be fully clarified. Although the current therapeutic strategies targeting pancreatic stellate cells show good efficacy in cell culture and animal models, they are not satisfactory in the clinic. Without effective intervention, pancreatic fibrosis can promote the transformation from pancreatitis to pancreatic cancer, one of the most lethal malignancies. In the normal pancreas, the acinar component accounts for 82% of the exocrine tissue. Abnormal acinar cells may activate pancreatic stellate cells directly as cellular source of fibrosis or indirectly via releasing various substances and initiate pancreatic fibrosis. A comprehensive understanding of the role of acinar cells in pancreatic fibrosis is critical for designing effective intervention strategies. In this review, we focus on the role of and mechanisms underlying pancreatic acinar injury in pancreatic fibrosis and their potential clinical significance.

Update on the sources, pharmacokinetics, pharmacological action, and clinical application of anisodamine

Anisodamine is an anticholinergic drug extracted and isolated from the Anisodus tanguticus (Maxim.) Pascher of the Solanaceae family which is also a muscarinic receptor antagonist. Owing to the lack of natural sources of anisodamine, synthetic products are now used. Using ornithine and arginine as precursor compounds, putrescine is catalyzed by different enzymes and then undergoes a series of reactions to produce anisodamine. It has been used clinically to protect cardiac function and treat septic shock, acute pancreatitis, calculous renal colic, bronchial asthma, blood circulation disturbances, jaundice, analgesia, vertigo, acute poisoning, and other conditions.This review describes the relevant pharmacokinetic parameters. Anisodamine is poorly absorbed in the gastrointestinal tract, and it is not as effective as intravenous administration. For clinical medication, intravenous infusion should be used rather than rapid intravenous injection. With the advancement of research in recent years, the application scope of anisodamine has expanded, with significant developments and application values surging.This review systematically describes the sources, pharmacokinetics, pharmacological effects and clinical application of anisodamine, in order to provide a basis for clinical use.

The role of NLRP3 inflammasome in hepatocellular carcinoma

Inflammasomes play an important role in innate immunity. As a signal platform, they deal with the excessive pathogenic products and cellular products related to stress and injury. So far, the best studied and most characteristic inflammasome is the NLR-family pyrin domain-containing protein 3(NLRP3) inflammasome, which is composed of NLRP3, apoptosis associated speck like protein (ASC) and pro-caspase-1. The formation of NLRP3 inflammasome complexes results in the activation of caspase-1, the maturation of interleukin (IL)-1β and IL-18, and pyroptosis. Many studies have demonstrated that NLRP3 inflammasome not only participates in tumorigenesis, but also plays a protective role in some cancers. Hepatocellular carcinoma (HCC) is a major cause of cancer-related mortality. Currently, due to the lack of effective treatment methods for HCC, the therapeutic effect of HCC has not been ideal. Therefore, it is particularly urgent to explore the pathogenesis of HCC and find its effective treatment methods. The increasing evidences indicate that NLRP3 inflammasome plays a vital role in HCC, however, the related mechanisms are not fully understood. Hence, we focused on the recent progress about the role of NLRP3 inflammasome in HCC, and analyzed the relevant mechanisms in detail to provide reference for the future in-depth researches.

Thioredoxin-interacting protein deficiency protects against severe acute pancreatitis by suppressing apoptosis signal-regulating kinase 1

Acute pancreatitis is a common acute inflammatory abdominal disease. When acute pancreatitis progresses to severe acute pancreatitis (SAP), it can lead to systemic inflammation and even multiple organ failure. Thioredoxin-interacting protein (TXNIP) is an important protein involved in redox reactions of the inflammatory response. However, the specific role of TXNIP in SAP remains unclear. In this study, we investigated the role of thioredoxin interacting protein (TXNIP) in acute pancreatitis when induced by high doses of arginine. We found that pancreatic damage and the inflammatory response associated with acute pancreatitis were largely restrained in TXNIP knock-out mice but were enhanced in mice overexpressing TXNIP. Interestingly, the phosphorylation of p38, JNK, and ASK1 diminished in TXNIP-KO mice with pancreatitis in comparison with wild-type mice. The role of oxidative stress in SAP was explored in two models: TXNIP and AVV-TXNIP. TXNIP knockdown or the inhibition of ASK1 by gs-4997 abrogated the increase in p-p38, p-JNK, and p-ASK1 in AR42J cells incubated with L-Arg. The administration of gs-4997 to mice with pancreatitis largely reduced the upregulation of IL-6, IL-1β, TNF-α, and MCP-1. Systemic inflammatory reactions and injury in the lungs and kidneys were assessed in TXNIP-KO and AVV-TXNIP mice with expected outcomes. In conclusion, TXNIP is a novel mediator of SAP and exerts action by regulating inflammatory responses and oxidative stress via the ASK1-dependent activation of the JNK/p38 pathways. Thus, targeting TXNIP may represent a promising approach to protect against SAP.

Pyroptosis in acute pancreatitis and its therapeutic regulation

Pyroptosis defines a new type of GSDMs-mediated programmed cell death, distinguishes from the classical concepts of apoptosis and necrosis-mediated cell death and is prescribed by cell swelling and membrane denaturation, leading to the extensive secretion of cellular components and low-grade inflammatory response. However, NLRP3 inflammasome activation can trigger its downstream inflammatory cytokines, leading to the activation of pyroptosis-regulated cell death. Current studies reveal that activation of caspase-4/5/11-driven non-canonical inflammasome signaling pathways facilitates the pathogenesis and progression of acute pancreatitis (AP). In addition, a large number of studies have reported that NLRP3 inflammasome-dependent pyroptosis is a crucial player in driving the course of the pathogenesis of AP. Excessive uncontrolled GSDMD-mediated pyroptosis has been implicated in AP. Therefore, the pyroptosis-related molecule GSDMD may be an independent prognostic biomarker for AP. The present review paper summarizes the molecular mechanisms of pyroptotic signaling pathways and their pathophysiological impacts on the progress of AP. Moreover, we briefly present some experimental compounds targeting pyroptosis-regulated cell death for exploring novel therapeutic directions for the treatment and management of AP. Our review investigations strongly suggest that targeting pyroptosis could be an ideal therapeutic approach in AP.

Anisodamine enhances macrophage M2 polarization through suppressing G9a-mediated IRF4 silencing to alleviate LPS-induced acute lung injury

Acute lung injury (ALI) is a serious inflammatory lung disease. Imbalances in the polarization of classically activated (M1) and alternatively activated (M2) macrophages are closely related to ALI. Anisodamine has a promising therapeutic effect for septic shock. Nevertheless, the role of Anisodamine in progression of ALI remains to be investigated. Our results showed that Anisodamine significantly reduced lung damage, myeloperoxidase (MPO) activity, lung wet/dry ratio, total cell number and protein concentrations in bronchoalveolar lavage fluid (BALF), and decreased IL-6 level and the levels of M1 phenotypic markers, while increased IL-10 level and the levels of M2 phenotypic markers in mice with a nasal instillation of lipopolysaccharide (LPS). Bone marrow-derived macrophages (BMDMs) were stimulated or transfected with LPS plus Anisodamine or LPS plus G9a shRNA. Anisodamine and downregulation of G9a both promoted BMDM M2 polarization caused by IL-4 treatment and inhibited M1 polarization resulted from LPS treatment. ChIP assay revealed that Anisodamine inhibited G9a-mediated methylation and expression suppression on IRF4. Overexpression of G9a or silence of IRF4 reversed the improvement effect of Anisodamine on lung tissue injury, evidencing by an increase of MPO activity and the restoration of LPS-induced alterations of M1 and M2 polarization. In conclusion, Anisodamine protected against LPS-induced ALI, during which Anisodamine suppressed the LPS-stimulated alterations of macrophage M1 and M2 polarization through inhibiting G9a mediated methylation of IRF4, suggesting that Anisodamine was a potential therapeutic drug to alleviate ALI. Significance Statement Anisodamine treatment was able to attenuate lung injury and pulmonary edema after the stimulation of LPS, and the specific mechanism was through reversing the LPS-induced alterations of M1 and M2 polarization by inhibiting G9a mediated silencing of IRF4, which suggests the Anisodamine has the potential to alleviate ALI.

The Effects of NLRP3 Inflammasome Inhibition in Experimental Acute Pancreatitis: A Systematic Review and Meta-Analysis

ABSTRACT

Acute pancreatitis (AP) is an inflammatory disease, and NLRP3 inflammasome activation is involved in the pathogenesis of AP. Previous research showed that inhibition of NLRP3 inflammasome may exert protective effects on animal models of AP and reduces disease severity. The aim of this systematic review and meta-analysis is to evaluate the effects of drug treatment of NLRP3 inflammasome on the outcomes of experimental AP. PubMed, Embase, Medline, and Web of Science databases were searched for relevant articles without language restrictions. The main outcomes for this study included local pancreatic injury, the incidence of systemic inflammatory responses, and the incidence of organ failure. Twenty-eight animal studies including 556 animals with AP were included in the meta-analysis. Compared with controls, inhibition of NLRP3 inflammasome significantly reduced the pancreatic histopathological scores, serum amylase, and lipase levels. In addition, inhibition of NLRP3 inflammasome reduced the levels of circulating inflammatory cytokines, as well as mitigating severity of AP-associated acute lung injury and acute intestinal injury. To conclude, inhibition of NLRP3 inflammasome has protective effects on AP by mitigating organ injury and systemic inflammation in animal studies, indicating that NLRP3 inflammasome holds promise as a target for specific AP therapy.

miR-340-5p inhibits pancreatic acinar cell inflammation and apoptosis via targeted inhibition of HMGB1

Acute pancreatitis (AP) is a common gastrointestinal disease that affects 1 million individuals worldwide. Inflammation and apoptosis are considered to be important pathogenic mechanisms of AP, and high mobility group box 1 (HMGB1) has been shown to play a particularly important role in the etiology of this disease. MicroRNAs (miRs) are emerging as critical regulators of gene expression and, as such, they represent a promising area of therapeutic target identification and development for a variety of diseases, including AP. Using the online database query (microRNA.org), the current study identified a site in the 3' untranslated region of HMGB1 mRNA that was a viable target for miR-340-5p. The present study aimed to investigate the association between miR-340-5p and HMGB1 expression in pancreatic acinar cells following lipopolysaccharide (LPS) treatment by performing luciferase, western blotting and reverse transcription-quantitative PCR assays. The results suggest that miR-340-5p attenuates the induction of HMGB1 by LPS, thereby inhibiting inflammation and apoptosis via blunted activation of Toll-like receptor 4 and enhanced AKT signaling. Thus, the therapeutic application of miR-340-5p may be a useful strategy in AP via upregulation of HMGB1 and subsequent promotion of inflammation and apoptosis.

Baicalein alleviates pyroptosis and inflammation in hyperlipidemic pancreatitis by inhibiting NLRP3/Caspase-1 pathway through the miR-192-5p/TXNIP axis

OBJECTIVE

Hyperlipidemia is a main reason of pancreatitis. Baicalein can ameliorate the pathological manifestations of pancreatitis. This study evaluated underlying molecular mechanism of baicalein in hyperlipidemic pancreatitis (HP).

METHODS

HP rat model was successfully established and treated with baicalein. Amylase (AMY) activity and concentrations of triglyceride (TG) and total cholesterol (TC) were detected. Levels of pyroptosis-related proteins (GSDMD, IL-1β, IL-18) were detected by Western blot. Expressions of inflammatory factors (IL-6, TNF-α, IL-4) were detected by ELISA. Toxicity of baicalein on pancreatic acinar cells (PACs) was detected by MTT assay. HP cell model was established by 0.1 mM palmitic acid and CCK-8 stimulation. Target relation of miR-192-5p and TXNIP was predicted and verified by RNA22 v2 database and dual-luciferase reporter assay. Expressions of miR-192-5p and TXNIP were detected by RT-qPCR. Pyroptosis and inflammation in PACs were detected after baicalein treatment combined with silencing miR-192-5p or TXNIP overexpression. Protein levels of NLRP3/Caspase-1 pathway in vivo and vitro were detected.

RESULTS

Baicalein reduced concentrations of TG and TC, AMY activity, and pathological scores in HP rat model, reduced LDH activity, pyroptosis and alleviated inflammation in vivo and in vitro. Mechanically, miR-192-5p targeted TXNIP, and baicalein inhibited pyroptosis and inflammation by up-regulating miR-192-5p and down-regulating TXNIP. Silencing miR-192-5p or TXNIP overexpression partially abolished the anti-pyroptosis and anti-inflammatory effect of baicalein on PACs. Baicalein attenuated HP by inhibiting the NLRP3/Caspase-1 pathway.

CONCLUSION

Baicalein alleviated pyroptosis and inflammation in HP by inhibiting the NLRP3/Caspase-1 pathway through miR-192-5p upregulation and TXNIP inhibition.

Protective effect of anisodamine hydrobromide on lipopolysaccharide-induced acute kidney injury

Anisodamine hydrobromide (AniHBr) is a Chinese medicine used to treat septic shock. However, whether AniHBr could ameliorate septic acute kidney injury and the underlying mechanism were not investigated. In the present study, 18 male Sprague-Dawley rats (200–250 g) were randomly divided into control, lipopolysaccharide (LPS) and LPS+AniHBr groups. Rats were intravenously administrated with LPS or normal saline (for control). After 4 h, the rats were intravenously administrated with AniHBr (LPS+AniHBr) or normal saline at 4 h intervals. Hemodynamic parameters including blood pressure and heart rate were measured. The histopathologic evaluation of kidney tissues was performed. Lactate, creatine kinase, inflammatory cytokines and oxidative stress indicators were determined. Using Seahorse analysis, the metabolic analysis of mitochondrial stress and glycolytic stress in human renal proximal tubular epithelial cells treated with TNF-α in the presence of AniHBr was performed. AniHBr administration significantly reduced serum creatine kinase and lactate following LPS treatment. AniHBr significantly improved hemodynamics in sepsis rats including increase in the mean atrial pressure and reduction in the heart rate. AniHBr significantly attenuated LPS-induced TNF-α, IL-6 and IL-1β in serum, and LPS-induced TNF-α and IL-1β in renal tissues. The LPS-reduced SOD activity and LPS-increased MDA content were reversed by AniHBr. In vitro, TNF-α increased mitochondrial oxygen consumption and glycolysis, but inhibited the ATP generation, which was reversed by AniHBr. Thus, AniHBr protects against the LPS-induced inflammatory cytokines, mitochondrial dysfunction and oxidative stress, and thus attenuates the LPS-induced acute kidney injury, showing AniHBr is a promising therapeutic drug for septic kidney injury.

A narrative review of acute pancreatitis and its diagnosis, pathogenetic mechanism, and management

Acute pancreatitis (AP) is an inflammatory disease that can progress to severe acute pancreatitis (SAP), which increases the risk of death. AP is characterized by inappropriate activation of trypsinogen, infiltration of inflammatory cells, and destruction of secretory cells. Other contributing factors may include calcium (Ca²⁺) overload, mitochondrial dysfunction, impaired autophagy, and endoplasmic reticulum (ER) stress. In addition, exosomes are also associated with pathophysiological processes of many human diseases and may play a biological role in AP. However, the pathogenic mechanism has not been fully elucidated and needs to be further explored to inform treatment. Recently, the treatment guidelines have changed; minimally invasive therapy is advocated more as the core multidisciplinary participation and "step-up" approach. The surgical procedures have gradually changed from open surgery to minimally invasive surgery that primarily includes percutaneous catheter drainage (PCD), endoscopy, small incision surgery, and video-assisted surgery. The current guidelines for the management of AP have been updated and revised in many aspects. The type of fluid to be used, the timing, volume, and speed of administration for fluid resuscitation has been controversial. In addition, the timing and role of nutritional support and prophylactic antibiotic therapy, as well as the timing of the surgical or endoscopic intervention, and the management of complications still have many uncertainties that could negatively impact the prognosis and patients' quality of life. Consequently, to inform clinicians about optimal treatment, we aimed to review recent advances in the understanding of the pathogenesis of AP and its diagnosis and management.