Spautin-1 Ameliorates Acute Pancreatitis via Inhibiting Impaired Autophagy and Alleviating Calcium Overload

Interleukin-22 Alleviates Caerulein-Induced Acute Pancreatitis by Activating AKT/mTOR Pathway

BACKGROUND

Acute pancreatitis (AP) is one of the most common acute abdominal disorders; due to the lack of specific treatment, the treatment of acute pancreatitis, especially serious acute pancreatitis (SAP), is difficult and challenging. We will observe the changes of Interleukin -22 levels in acute pancreatitis animal models, and explore the mechanism of Interleukin -22 in acute pancreatitis.

OBJECTIVE

This study aims to assess the potential protective effect of Interleukin -22 on caerulein-induced acute pancreatitis and to explore its mechanism.

METHODS

Blood levels of amylase and lipase and Interleukin -22 were assessed in mice with acute pancreatitis. In animal model and cell model of caerulein-induced acute pancreatitis, the mRNA levels of P62 and Beclin-1 were determined using PCR, and the protein expression of P62, LC3-II, mTOR, AKT, p-mTOR, and p-AKT were evaluated through Western blot analysis.

RESULTS

Interleukin -22 administration reduced blood amylase and lipase levels and mitigated tissue damage in acute pancreatitis mice model. Interleukin -22 inhibited the relative mRNA levels of P62 and Beclin-1, and the Interleukin -22 group showed a decreased protein expression of LC3-II and P62 and the phosphorylation of the AKT/mTOR pathway. Furthermore, we obtained similar results in the cell model of acute pancreatitis.

CONCLUSION

This study suggests that Interleukin -22 administration could alleviate pancreatic damage in caerulein-induced acute pancreatitis. This effect may result from the activation of the AKT/mTOR pathway, leading to the inhibition of autophagy. Consequently, Interleukin -22 shows potential as a treatment.

Interleukin‑22 alleviates arginine‑induced pancreatic acinar cell injury via the regulation of intracellular vesicle transport system: Evidence from proteomic analysis

Acute pancreatitis (AP) is a severe inflammatory condition characterized by the activation of pancreatic enzymes within acinar cells, leading to tissue damage and inflammation. Interleukin (IL)-22 is a potential therapeutic agent for AP owing to its anti-inflammatory properties and ability to promote tissue repair. The present study evaluated the differentially expressed proteins in arginine-induced pancreatic acinar cell injury following treatment with IL-22, and the possible mechanisms involved in IL-22-mediated alleviation of AP. AR42J cells were stimulated using L-arginine to establish an acinar cell injury model in vitro and the damaged cells were subsequently treated with IL-22. The characteristics of the model and the potential therapeutic effects of IL-22 were examined by CCK-8 assay, flow cytometry, TUNEL assay, transmission electron microscopy and ELISA. Differentially expressed proteins in cells induced by arginine and treated with IL-22 were assessed using liquid chromatography-mass spectrometry. The identified proteins were further subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis to elucidate their functional roles. The present study demonstrated that arginine-stimulated cells showed significant pathological changes resembling those in AP, which were alleviated after IL-22 treatment. Proteomic analysis then demonstrated that in IL-22-treated cells, proteins related to the formation and fusion of autophagosomes with lysosomes were significantly downregulated, whereas endocytosis related proteins were enriched in the upregulated proteins. After IL-22 treatment, western blotting demonstrated reduced expression of autophagy-associated proteins. In conclusion, by inhibiting the formation and fusion of autophagosomes with lysosomes, IL-22 may have mitigated premature trypsinogen activation, subsequently minimizing acinar cell injury induced by L-arginine. This was accompanied by concurrent upregulation of endocytosis, which serves a pivotal role in sustaining regular cellular material transport and signal propagation. This research underscored the potential of IL-22 in mitigating arginine-induced AR42J injury, which could be valuable in refining treatment strategies for AP.

Targeting autophagy in pancreatic cancer: The cancer stem cell perspective

Pancreatic cancer is currently the seventh leading cause of cancer-related deaths worldwide, with the estimated death toll approaching half a million annually. Pancreatic ductal adenocarcinoma (PDAC) is the most common (>90% of cases) and most aggressive form of pancreatic cancer, with extremely poor prognosis and very low survival rates. PDAC is initiated by genetic alterations, usually in the oncogene KRAS and tumor suppressors CDKN2A, TP53 and SMAD4, which in turn affect a number of downstream signaling pathways that regulate important cellular processes. One of the processes critically altered is autophagy, the mechanism by which cells clear away and recycle impaired or dysfunctional organelles, protein aggregates and other unwanted components, in order to achieve homeostasis. Autophagy plays conflicting roles in PDAC and has been shown to act both as a positive effector, promoting the survival of pancreatic tumor-initiating cells, and as a negative effector, increasing cytotoxicity in uncontrollably expanding cells. Recent findings have highlighted the importance of cancer stem cells in PDAC initiation, progression and metastasis. Pancreatic cancer stem cells (PaCSCs) comprise a small subpopulation of the pancreatic tumor, characterized by cellular plasticity and the ability to self-renew, and autophagy has been recognised as a key process in PaCSC maintenance and function, simultaneously suggesting new strategies to achieve their selective elimination. In this review we evaluate recent literature that links autophagy with PaCSCs and PDAC, focusing our discussion on the therapeutic implications of pharmacologically targeting autophagy in PaCSCs, as a means to treat PDAC.

Trends and recent developments in pharmacotherapy of acute pancreatitis

Acute pancreatitis (AP), a complex inflammatory disease of the pancreas, is associated with increased morbidity and mortality. Currently, no specific therapies are approved for its treatment, and management is primarily based on supportive care. Despite enhanced understanding of AP pathogenesis, patients remain at significant risk owing to a lack of targeted drug treatments. Therefore, there is an urgent need for effective pharmacological therapeutic measures which may inhibit the early systemic inflammation, thereby preventing subsequent organ failure. This narrative review summarizes the available treatment options for AP and highlights the potential drug classes and pharmacologic therapies including those under clinical development. Although, several therapies targeting different aspects of AP pathogenesis have been investigated, some therapies with promising preclinical activity have been rendered ineffective in clinical trials. Other novel drug classes or molecules including dabigatran (anticoagulant), ulinastatin (protease inhibitor), infliximab (monoclonal antibody), spautin-A41 (autophagy inhibitor), and CM4620-Injectible Emulsion (calcium channel inhibitor) await further clinical assessment. Alternative treatment options using stem cells and nanoparticles are also being explored and may hold promise for AP therapy. However, challenges for exploring targeted treatment approaches include disease complexity, timing of therapeutic intervention, and establishing appropriate clinical endpoints. Understanding the role of specific biomarkers may help in identifying appropriate targets for drug discovery and facilitate determining relevant clinical study endpoints to monitor disease severity and progression, thereby aiding in design of more precise therapies with improved clinical outcomes.

Autophagy: A Key Player in Pancreatic Cancer Progression and a Potential Drug Target

Simple Summary

With the mortality rate of pancreatic cancer predicted to rise over the coming years, it is essential that effective treatment strategies are developed as soon as possible. Pancreatic cancer has always proven very difficult to treat due to its fast growing and aggressive nature. Chemotherapeutic treatment has struggled to increase the survival rate of pancreatic cancer patients due to effective chemo-resistant properties that derive from the supporting tumor microenvironment and autophagy, a vital survival pathway. This review will explore how the autophagy pathway and tumor microenvironment help to sustain tumor survival under stress and expand into a metastatic state. Due to the comprehensive understanding of the autophagy pathway, we will highlight the potential chinks in the pancreatic tumor’s armor and identify potential targets to overcome chemo-resistance in pancreatic cancer. We will also present novel autophagy inhibitors that could reduce tumor survival and how they could be most effectively conceived.

Abstract

Pancreatic cancer is known to have the lowest survival outcomes among all major cancers, and unfortunately, this has only been marginally improved over last four decades. The innate characteristics of pancreatic cancer include an aggressive and fast-growing nature from powerful driver mutations, a highly defensive tumor microenvironment and the upregulation of advantageous survival pathways such as autophagy. Autophagy involves targeted degradation of proteins and organelles to provide a secondary source of cellular supplies to maintain cell growth. Elevated autophagic activity in pancreatic cancer is recognized as a major survival pathway as it provides a plethora of support for tumors by supplying vital resources, maintaining tumour survival under the stressful microenvironment and promoting other pathways involved in tumour progression and metastasis. The combination of these features is unique to pancreatic cancer and present significant resistance to chemotherapeutic strategies, thus, indicating a need for further investigation into therapies targeting this crucial pathway. This review will outline the autophagy pathway and its regulation, in addition to the genetic landscape and tumor microenvironment that contribute to pancreatic cancer severity. Moreover, this review will also discuss the mechanisms of novel therapeutic strategies that inhibit autophagy and how they could be used to suppress tumor progression.

Novel Effects of Statins on Cancer via Autophagy

Cancer is one of the main causes of death globally. Most of the molecular mechanisms underlying cancer are marked by complex aberrations that activate the critical cell-signaling pathways that play a pivotal role in cell metabolism, tumor development, cytoskeletal reorganization, and metastasis. The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of the rapamycin (PI3K/AKT/mTOR) pathway is one of the main signaling pathways involved in carcinogenesis and metastasis. Autophagy, a cellular pathway that delivers cytoplasmic components to lysosomes for degradation, plays a dual role in cancer, as either a tumor promoter or a tumor suppressor, depending on the stage of the carcinogenesis. Statins are the group of drugs of choice to lower the level of low-density lipoprotein (LDL) cholesterol in the blood. Experimental and clinical data suggest the potential of statins in the treatment of cancer. In vitro and in vivo studies have demonstrated the molecular mechanisms through which statins inhibit the proliferation and metastasis of cancer cells in different types of cancer. The anticancer properties of statins have been shown to result in the suppression of tumor growth, the induction of apoptosis, and autophagy. This literature review shows the dual role of the autophagic process in cancer and the latest scientific evidence related to the inducing effect exerted by statins on autophagy, which could explain their anticancer potential.

ATG7-enhanced impaired autophagy exacerbates acute pancreatitis by promoting regulated necrosis via the miR-30b-5p/CAMKII pathway

The present study was performed to explore whether and how impaired autophagy could modulate calcium/calmodulin-dependent protein kinase II (CAMKII)-regulated necrosis in the pathogenesis of acute pancreatitis (AP). Wistar rats and AR42J cells were used for AP modeling. When indicated, genetic regulation of CAMKII or ATG7 was performed prior to AP induction. AP-related necrotic injury was positively regulated by the incubation level of CAMKII. ATG7 positively modulated the level of CAMKII and necrosis following AP induction, indicating that there might be a connection between impaired autophagy and CAMKII-regulated necrosis in the pathogenesis of AP. microRNA (miR)-30b-5p was predicted and then verified as the upstream regulator of CAMKII mRNA in our setting of AP. Given that the level of miR-30b-5p was negatively correlated with the incubation levels of ATG7 after AP induction, a rescue experiment was performed and indicated that the miR-30b-5p mimic compromised ATG7 overexpression-induced upregulation of CAMKII-regulated necrosis after AP induction. In conclusion, our results indicate that ATG7-enhanced impaired autophagy exacerbates AP by promoting regulated necrosis via the miR-30b-5p/CAMKII pathway.

Resolvin D1 Suppresses H2O2-Induced Senescence in Fibroblasts by Inducing Autophagy through the miR-1299/ARG2/ARL1 Axis

ARG2 has been reported to inhibit autophagy in vascular endothelial cells and keratinocytes. However, studies of its mechanism of action, its role in skin fibroblasts, and the possibility of promoting autophagy and inhibiting cellular senescence through ARG2 inhibition are lacking. We induced cellular senescence in dermal fibroblasts by using H2O2. H2O2-induced fibroblast senescence was inhibited upon ARG2 knockdown and promoted upon ARG2 overexpression. The microRNA miR-1299 suppressed ARG2 expression, thereby inhibiting fibroblast senescence, and miR-1299 inhibitors promoted dermal fibroblast senescence by upregulating ARG2. Using yeast two-hybrid assay, we found that ARG2 binds to ARL1. ARL1 knockdown inhibited autophagy and ARL1 overexpression promoted it. Resolvin D1 (RvD1) suppressed ARG2 expression and cellular senescence. These data indicate that ARG2 stimulates dermal fibroblast cell senescence by inhibiting autophagy after interacting with ARL1. In addition, RvD1 appears to promote autophagy and inhibit dermal fibroblast senescence by inhibiting ARG2 expression. Taken together, the miR-1299/ARG2/ARL1 axis emerges as a novel mechanism of the ARG2-induced inhibition of autophagy. Furthermore, these results indicate that miR-1299 and pro-resolving lipids, including RvD1, are likely involved in inhibiting cellular senescence by inducing autophagy.

Novel Ubiquitin Specific Protease-13 Inhibitors Alleviate Neurodegenerative Pathology

Ubiquitin Specific Protease-13 (USP13) promotes protein de-ubiquitination and is poorly understood in neurodegeneration. USP13 is upregulated in Alzheimer’s disease (AD) and Parkinson’s disease (PD), and USP13 knockdown via shRNA reduces neurotoxic proteins and increases proteasome activity in models of neurodegeneration. We synthesized novel analogues of spautin-1 which is a non-specific USP13 inhibitor but unable to penetrate the brain. Our synthesized small molecule compounds are able to enter the brain, more potently inhibit USP13, and significantly reduce alpha-synuclein levels in vivo and in vitro. USP13 inhibition in transgenic mutant alpha-synuclein (A53T) mice increased the ubiquitination of alpha-synuclein and reduced its protein levels. The data suggest that novel USP13 inhibitors improve neurodegenerative pathology via antagonism of de-ubiquitination, thus alleviating neurotoxic protein burden in neurodegenerative diseases.

Targeting USP13-mediated drug tolerance increases the efficacy of EGFR inhibition of mutant EGFR in non-small cell lung cancer

In non-small cell lung cancer (NSCLC), activating mutations in the epidermal growth factor receptor (EGFR) induce sensitivity to EGFR tyrosine kinase inhibitors. Despite impressive clinical responses, patients ultimately relapse as a reservoir of drug-tolerant cells persist, which ultimately leads to acquired resistance mechanisms. We performed an unbiased high-throughput siRNA screen to identify proteins that abrogate the response of EGFR-mutant NSCLC to EGFR-targeted therapy. The deubiquitinase USP13 was a top hit resulting from this screen. Targeting USP13 increases the sensitivity to EGFR inhibition with small molecules in vitro and in vivo. USP13 selectively stabilizes mutant EGFR in a peptidase-independent manner by counteracting the action of members of the Cbl family of E3 ubiquitin ligases. We conclude that USP13 is a strong mutant EGFR-specific cotarget that could improve the treatment efficacy of EGFR-targeted therapies.

Roles of Specialized Pro-Resolving Lipid Mediators in Autophagy and Inflammation

Autophagy is a catabolic pathway that accounts for degradation and recycling of cellular components to extend cell survival under stress conditions. In addition to this prominent role, recent evidence indicates that autophagy is crucially involved in the regulation of the inflammatory response, a tightly controlled process aimed at clearing the inflammatory stimulus and restoring tissue homeostasis. To be efficient and beneficial to the host, inflammation should be controlled by a resolution program, since uncontrolled inflammation is the underlying cause of many pathologies. Resolution of inflammation is an active process mediated by a variety of mediators, including the so-called specialized pro-resolving lipid mediators (SPMs), a family of endogenous lipid autacoids known to regulate leukocyte infiltration and activities, and counterbalance cytokine production. Recently, regulation of autophagic mechanisms by these mediators has emerged, uncovering unappreciated connections between inflammation resolution and autophagy. Here, we summarize mechanisms of autophagy and resolution, focusing on the contribution of autophagy in sustaining paradigmatic examples of chronic inflammatory disorders. Then, we discuss the evidence that SPMs can restore dysregulated autophagy, hypothesizing that resolution of inflammation could represent an innovative approach to modulate autophagy and its impact on the inflammatory response.

Mogroside IIE Inhibits Digestive Enzymes via Suppression of Interleukin 9/Interleukin 9 Receptor Signalling in Acute Pancreatitis

The incidence of pancreatitis (AP) is increasing and there is no specific treatment available. Intracellular digestive enzyme activation is a key event in the pathogenesis of AP downstream of cytosolic calcium overload and impaired autophagy. Siraitia grosvenorii (Swingle) was used in Traditional Chinese Medicine to reduce inflammation and facilitate bowel movement. The bioactive components of this plant show hypolipedimic, antidiabetic, antifibrotic activity and have been used against pancreatic cancer. Here, we examined whether mogroside II_E, a major bioactive component of unripe S. grosvenorii fruit, can protect against AP. We found that mogroside II_E decreased the activity of trypsin and cathepsin B induced by cerulein plus lipopolysaccharide (LPS) in the pancreatic acinar cell line AR42J and primary acinar cells in a dose- and time-dependent manner. Mogroside II_E treatment decreased the levels of serum lipase and serum amylase in mice injected with cerulein plus LPS without influencing inflammation significantly. A multi-cytokine array revealed that mogroside II_E decreased the level of interleukin 9 (IL-9) in AP mice. Exogenous IL-9 eliminated the mogroside II_E induced reduction of trypsin and cathepsin B activity and reversed the inhibition of cytosolic calcium and modulation of autophagy mediated by mogroside II_E. An IL-9 receptor antibody neutralized the effect of IL-9, restoring mogroside II_E activity. The mogroside II_E targeted IL-9 may partially arise from Th9 cells. Taken together, we provide experimental evidence that mogroside II_E ameliorates AP in cell models and mice through downregulation of the IL-9/IL-9 receptor pathway.

Fibroblast growth factor 21 alleviates acute pancreatitis via activation of the Sirt1-autophagy signalling pathway

Fibroblast growth factor 21 (FGF21), a metabolic hormone with pleiotropic effects on glucose and lipid metabolism and insulin sensitivity, alleviates the process of acute pancreatitis (AP). However, its mechanism remains elusive. The pathological and physiological characteristics of FGF21 are observed in both patients with AP and cerulein‐induced AP models, and the mechanisms of FGF21 in response to AP are investigated by evaluating the impact of autophagy in FGF21‐treated mice and cultured pancreatic cells. Circulating levels of FGF21 significantly increase in both AP patients and cerulein‐induced AP mice, which is accompanied by the change of pathology in pancreatic injury. Replenishment of FGF21 distinctly reverses cerulein‐induced pancreatic injury and improves cerulein‐induced autophagy damage in vivo and in vitro. Mechanically, FGF21 acts on pancreatic acinar cells to up‐regulate Sirtuin‐1 (Sirt1) expression, which in turn repairs impaired autophagy and removes damaged organs. In addition, blockage of Sirt1 accelerates cerulein‐induced pancreatic injury and weakens the regulative effect in FGF21‐activated autophagy in mice. These results showed that FGF21 protects against cerulein‐induced AP by activation of Sirtuin‐1‐autophagy axis.

CaMKII/proteasome/cytosolic calcium/cathepsin B axis was present in tryspin activation induced by nicardipine

Premature trypsinogen activation is the early event of acute pancreatitis. Therefore, the studies on the processes of trypsinogen activation induced by compounds are important to understand mechanism underly acute pancreatitis under various conditions. Calcium overload in the early stage of acute pancreatitis was previously found to cause intracellular trypsinogen activation; however, treatment of acute pancreatitis using calcium channel blockers did not produced consistent results. Proteasome activity that could be inhibited by some calcium channel blocker has recently been reported to affect the development of acute pancreatitis; however, the associated mechanism were not fully understood. Here, the roles of nicardipine were investigated in trypsinogen activation in pancreatic acinar cells. The results showed that nicardipine could increase cathepsin B activity that caused trypsinogen activation, but higher concentration of nicardipine or prolonged treatment had an opposite effect. The effects of short time treatment of nicardipine at low concentration were studied here. Proteasome inhibition was observed under nicardipine treatment that contributed to the up-regulation in cytosolic calcium. Increased cytosolic calcium from ER induced by nicardipine resulted in the release and activation of cathepsin B. Meanwhile, calcium chelator inhibited cathepsin B as well as trypsinogen activation. Consistently, proteasome activator protected acinar cells from injury induced by nicardipine. Moreover, proteasome inhibition caused by nicardipine depended on CaMKII. In conclusion, CaMKII down-regulation/proteasome inhibition/cytosolic calcium up-regulation/cathepsin B activation/trypsinogen activation axis was present in pancreatic acinar cells injury under nicardipine treatment.

AMPK-mediated degradation of Nav1.5 through autophagy

The voltage-gated cardiac sodium channel, Nav1.5, is the key component that controls cardiac excitative electrical impulse and propagation. However, the dynamic alterations of Nav1.5 during cardiac ischemia and reperfusion (I/R) are seldom reported. We found that the protein levels of rat cardiac Nav1.5 were significantly decreased in response to cardiac I/R injury. By simulating I/R injury in cells through activating AMPK by glucose deprivation, AMPK activator treatment, or hypoxia and reoxygenation (H/R), we found that Nav1.5 was down-regulated by AMPK-mediated autophagic degradation. Furthermore, AMPK was found to phosphorylate Nav1.5 at threonine (T) 101, which then regulates the interaction between Nav1.5 and the autophagic adaptor protein, microtubule-associated protein 1 light chain 3 (LC3), by exposing the LC3-interacting region adjacent to T101 in Nav1.5. This study highlights an instrumental role of AMPK in mediating the autophagic degradation of Nav1.5 during cardiac I/R injury.-Liu, X., Chen, Z., Han, Z., Liu, Y., Wu, X., Peng, Y., Di, W., Lan, R., Sun, B., Xu, B., Xu, W. AMPK-mediated degradation of Nav1.5 through autophagy.

Resolvin D1 Resolve Inflammation in Experimental Acute Pancreatitis by Restoring Autophagic Flux

BACKGROUND

Acute pancreatitis (AP) is a common acute gastrointestinal disorders. Increasing evidence indicated that autophagy is involved in the development of AP. Resolvin D1 is an endogenous pro-resolving lipid mediator, which can protect mice from cerulein-induced acute pancreatitis and facilitate autophagy in macrophage, but its mechanism remians unclear.

AIMS

To investigate the effect of resolvin D1 on autophagy in mouse models of cerulein-induced AP.

METHODS

C57BL/6 mice were randomly divided into control group, AP group and resolvin D1 group. The models of cerulein-induced AP were constructed by intraperitoneally cerulein. Resolvin D1 group was established by intraperitoneally resolvin D1 based on AP models, simultaneously, control group received normal saline. The severity of AP, the level of inflammatory cytokines, the number of autophagic vacuoles, and the expression of autophagy-related markers were evaluated among three groups.

RESULTS

The AP models were established successfully. Compared to control group, the number of autophagic vacuoles and expressions of autophagy-related markers including Beclin-1, p62 and LC3-II were increased in AP models, In contrast, the degree of inflammation and levels of inflammatory cytokines in AP models were reduced after resolvin D1 treatment. Moreover, resolvin D1 attenuated the number of autophagic vacuoles and expressions of autophagy-related markers.

CONCLUSIONS

Autophagic flux is impaired in cerulein-induced AP. Resolvin D1 ameliorate the severity of mice with cerulein-induced acute pancreatitis, possible attributing to its reducing impaired autophagy and restoring autophagic flux.

The autophagy inhibitor spautin-1, either alone or combined with doxorubicin, decreases cell survival and colony formation in canine appendicular osteosarcoma cells

Dogs diagnosed with appendicular osteosarcoma typically succumb to metastatic disease within a year of diagnosis. The current standard of care for curative intent, amputation followed by adjuvant chemotherapy, increases survival time but chemoresistance is a major contributor to mortality. Unfortunately, the mechanisms driving the progression of metastatic disease and the development of chemoresistance are unknown. One theory is that autophagy may contribute to chemoresistance by providing neoplastic cells with a mechanism to survive chemotherapy treatment. Our objective was to evaluate the effect of combining an autophagy inhibitor with a standard chemotherapeutic drug on response to chemotherapy in canine appendicular osteosarcoma cells. We hypothesized that combining the autophagy inhibitor spautin-1 with doxorubicin treatment would enhance chemoresponsiveness. Using commercial (D17) and primary cell lines derived from 1° and 2° sites of osteosarcoma, we showed that this combination treatment enhances cell killing and inhibits colony formation. Our findings support the theory that autophagy contributes to chemoresistance in canine appendicular osteosarcoma and indicate that adding an autophagy inhibitor to the standard of care has the potential to improve outcome.

Regulation of Autophagy Affects the Prognosis of Mice with Severe Acute Pancreatitis

BACKGROUND

Acute pancreatitis (AP) is a common inflammatory disease that may develop to severe AP (SAP), resulting in life-threatening complications. Impaired autophagic flux is a characteristic of early AP, and its accumulation could activate oxidative stress and nuclear factor κB (NF-κB) pathways, which aggravate the disease process.

AIM

To explore the therapeutic effects of regulating autophagy after the onset of AP.

METHODS

In this study, intraperitoneal injections of 3-methyladenine (3-MA) and rapamycin (RAPA) in the L-arginine or cerulein plus lipopolysaccharide (LPS) Balb/C mouse model. At 24 h after the last injection, pulmonary, intestinal, renal and pancreatic tissues were analyzed.

RESULTS

We found that 3-MA ameliorated systemic organ injury in two SAP models. 3-MA treatment impaired autophagic flux and alleviated inflammatory activation by modulating the NF-κB signaling pathway and the caspase-1-IL-1β pathway, thus decreasing the injuries to the organs and the levels of inflammatory cytokines.

CONCLUSION

Our study found that the regulation of autophagy could alter the progression of AP induced by L-arginine or cerulein plus LPS in mice.

Design of Small Molecule Autophagy Modulators: A Promising Druggable Strategy

Autophagy is a lysosome-dependent mechanism of intracellular degradation for maintaining cellular homeostasis. Dysregulation of autophagy has been verified to be closely linked to a number of human diseases. Consequently, targeting autophagy has been highlighted as a novel therapeutic strategy for clinical utility. Mounting efforts have been done in recent years to elucidate the mechanisms of autophagy regulation and to identify potential modulators of autophagy. However, most of the compounds target complex and multifaceted pathway and proteins, which may limit the evaluation of therapeutic value and in depth studies as chemical tools. Therefore, the development of specific and active autophagy modulators becomes most desirable. Here, we briefly review the regulation of autophagy and then summarize the recent development of small molecules targeting the core autophagic machinery. Finally, we put forward our viewpoints on the current problems, with the aim to provide reference for future drug discovery and potential therapeutic perspectives on novel, potent, selective autophagy modulators.