The beneficial effect of resveratrol on severe acute pancreatitis

Therapeutic effects of resveratrol and β-carotene on L-arginine-induced acute pancreatitis through oxidative stress and inflammatory pathways in rats

Acute pancreatitis (AP) is a severe inflammatory condition affecting the pancreas, often leading to systemic inflammation and organ dysfunction. This study evaluated the effects of resveratrol (RES) and β-carotene (βC) on L-arginine-induced AP in rats. Forty-eight male Sprague Dawley rats were divided into six groups: Control (C), RES (20 mg/kg), βC (50 mg/kg), AP, AP + RES, and AP + βC. The AP model was induced with 250 mg/100 g L-arginine intraperitoneally twice daily with a 1-h interval. The AP group showed significantly elevated oxidative stress (MDA) and reduced GSH levels (p < 0.001). Immunohistochemical (IHC) staining with anti-insulin antibody revealed reduced β + langerhans islet size in the AP group. qPCR analysis indicated significant upregulation of inflammatory genes NF-κB, TNF-α, and IL-1β (p < 0.001), and apoptotic genes Bax and Caspase-3, with downregulation of Bcl-2 (p < 0.001). RES and βC treatments significantly reduced MDA levels and increased GSH levels (p < 0.01 for both) compared to the AP group. The AP + RES and AP + βC groups exhibited preserved β + Langerhans islet size (p < 0.01), suppressed NF-κB, TNF-α, and IL-1β expression, reduced Bax and Caspase-3 levels, and increased Bcl-2 levels (p < 0.01). Histopathological findings supported these results. RES and βC confer significant effects against L-arginine-induced acute pancreatitis by reducing oxidative stress, preserving pancreatic islet integrity, suppressing inflammatory responses, and modulating apoptotic pathways. RES demonstrated a slightly superior efficacy in reducing inflammation and oxidative stress markers, suggesting it may be more effective in treating acute pancreatitis.

Elucidating the mechanism of stigmasterol in acute pancreatitis treatment: insights from network pharmacology and in vitro/in vivo experiments

INTRODUCTION

Acute pancreatitis (AP) is a severe inflammatory disease of the pancreas that could trigger a systemic inflammation and multi-organ dysfunction. Stigmasterol, a natural plant sterol found in various herbs and vegetables, exhibits a significant anti-inflammatory, antioxidant, and cholesterol-lowering effects. However, its therapeutic potential in AP have not been thoroughly investigated.

METHODS

The present study employed network pharmacology combined with experimental verification to explore the protective effect of stigmasterol on AP and its molecular mechanism in a sodium taurocholate (STC)-induced AP mouse model.

RESULTS

Protein-protein interaction (PPI) analysis pinpointed out MAPK3, also named as ERK1, as a promising stigmasterol target in AP therapy. Molecular docking analysis further revealed a strong binding capacity of stigmasterol to ERK1 (-6.57 kL/mol). Furthermore, both in vivo and in vitro studies demonstrated that stigmasterol treatment notably attenuated STC-induced pancreatic injury, as evidented by decreased serum levels of lipase and amylase, improved systemic inflammation, and reduced acinar cell necrosis. At the molecular level, stigmasterol treatment exhibited a significant inhibition on STC-induced activation of ERK signaling pathway in pancreatic acinar cells, leading to the transition of acinar cell death from necrosis to apoptosis, thereby preventing acinar cell necrosis-induced systemic inflammation.

CONCLUSION

This study demonstrated that stigmasterol exhibits a significant protective effect aganist AP, at least in part through enhancing acinar cell apoptosis via modulating the ERK signaling pathways.

The role of Interleukin-22 in severe acute pancreatitis

Severe acute pancreatitis (SAP) begins with premature activation of enzymes, promoted by the immune system, triggering a potential systemic inflammatory response that leads to organ failure with increased mortality and a bleak prognosis. Interleukin-22 (IL-22) is a cytokine that may have a significant role in SAP. IL-22, a member of the IL-10 cytokine family, has garnered growing interest owing to its potential tissue-protective properties. Recently, emerging research has revealed its specific effects on pancreatic diseases, particularly SAP. This paper provides a review of the latest knowledge on the role of IL-22 and its viability as a therapeutic target in SAP.

Resveratrol suppresses cholestasis-induced liver injury and fibrosis in rats associated with the inhibition of TGFβ1-Smad3-miR21 axis and profibrogenic and hepatic injury biomarkers

Cholestasis caused by slowing or blockage of bile flow is a serious liver disease that can lead to liver fibrosis and cirrhosis. The link between transforming growth factor beta 1 (TGFβ1), Smad family member 3 (Smad3), and microRNA 21 (miR21) in bile duct ligation (BDL)-induced liver fibrosis in the presence and absence of the anti-inflammatory and antioxidant compound, resveratrol (RSV), has not been previously studied. Therefore, we tested whether RSV can protect against BDL-induced liver fibrosis associated with the inhibition of the TGFβ1-Smad3-miR21 axis and profibrogenic and hepatic injury biomarkers. The model group of rats had their bile duct ligated (BDL) for 3 weeks before being killed, whereas, the BDL-treated rats were separated into three groups that received 10, 20, and 30 mg/kg RSV daily until the end of the experiment. Using light microscopy and ultrasound examinations, we documented in the BDL group, the development of hepatic injury and fibrosis as demonstrated by hepatocytes necrosis, bile duct hyperplasia, collagen deposition, enlarged liver with increased echogenicity, irregular nodular border and dilated common bile duct, which were more effectively inhibited by the highest used RSV dosage. In addition, RSV significantly (p ≤ 0.0027) inhibited BDL-induced hepatic TGFβ1, Smad3, miR21, the profibrogenic biomarker tissue inhibitor of metalloproteinases-1 (TIMP-1), malondialdehyde (MDA), interleukin-17a (IL-17a), and blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin. These findings show that RSV at 30 mg/kg substantially protects against BDL-induced liver injuries, which is associated with the inhibition of TGFβ1-Smad3-miR21 axis, and biomarkers of profibrogenesis, oxidative stress, and inflammation.

Resveratrol Ameliorates the Malignant Progression of Pancreatic Cancer by Inhibiting Hypoxia-induced Pancreatic Stellate Cell Activation

Pancreatic cancer is characterized by a hypoxic tumor microenvironment, which is primarily caused by massive fibrosis with pancreatic stellate cells (PSCs) as a main component. Our previous studies have shown that resveratrol can significantly inhibit pancreatic cancer. However, whether resveratrol can inhibit hypoxia-induced cancer development remains unclear. The objective of this study was to explore whether PSCs and hypoxia synergistically mediate aggressiveness in pancreatic cancer and detect the potential pleiotropic protective effects of resveratrol on hypoxia-induced pancreatic cancer progression. Human PSCs were treated with vehicle or resveratrol under normoxic or hypoxic conditions (3% O2), and PSC activation was assessed by immunofluorescence staining. SiRNA was used to silence hypoxia-inducible factor 1 (HIF-1) expression. The invasive capacity of Panc-1 and Mia Paca-2 cells cocultured with conditioned medium from PSCs was assessed by Transwell assays. To examine tumor formation kinetics, KPC (LSL-KrasG12D/+, Trp53fl/+, and Pdx1-Cre) mice were sacrificed at different time points. To investigate the antitumor effects of resveratrol in vivo, 8-wk-old KPC mice were divided into two groups and treated daily with or without 50 mg/kg resveratrol. Our data indicate that hypoxia induces PSC activation via HIF-1 and that the interleukin 6, vascular endothelial growth factor A, and stromal cell-derived factor 1 derived from activated PSCs promote both invasion and the epithelial-mesenchymal transition and inhibit apoptosis in pancreatic cancer cells. However, resveratrol inhibits hypoxia-induced PSC activation, blocks the interplay between PSCs and pancreatic cancer cells, and suppresses the malignant progression of pancreatic cancer and stromal desmoplasia in a KPC mouse model. Our data highlight that activated PSCs and intratumoral hypoxia are essential targets for novel strategies to prevent tumor-microenvironment interactions. Furthermore, the polyphenolic compound resveratrol effectively ameliorates the malignant progression of pancreatic ductal adenocarcinoma.

Effectiveness and therapeutic value of phytochemicals in acute pancreatitis: A review

BACKGROUND

Acute pancreatitis (AP) is an inflammatory disorder of the pancreas that can lead to local and systemic complications. Repeated attacks of AP can lead to chronic pancreatitis, which markedly increases the probability of developing pancreatic cancer. Although many researchers have attempted to identify the pathogenesis involved in the initiation and aggravation of AP, the disease is still not fully understood, and effective treatment is limited to supportive therapy.

METHODS

We aim to summarize available literature focused on phytochemicals (berberine, chlorogenic acid, curcumin, emblica officinalis, ellagic acid, cinnamtannin B-1, resveratrol, piperine and lycopene) and discuss their effectiveness and therapeutic value for improving AP.

RESULTS

This study is based on pertinent papers that were retrieved by a selective search using relevant keywords in PubMed and ScienceDirect databases.

CONCLUSIONS

Many phytochemicals hold potential in improving AP symptoms and may be a valuable and effective addition to standard treatment of AP. It has already been proven that the crucial factor for reducing the severity of AP is stimulation of apoptosis along with/or inhibition of necrosis. Supplementation of phytochemicals, which target the balance between apoptosis and necrosis can be recommended in ongoing clinical studies.

Research Progress on the Relationship Between Acute Pancreatitis and Calcium Overload in Acinar Cells

Acute pancreatitis is a human disease with multiple causes that leads to autodigestion of the pancreas. There is sufficient evidence to support the key role of sustained increase in cytosolic calcium concentrations in the early pathogenesis of the disease. To clarify the mechanism of maintaining calcium homeostasis in the cell and pathological processes caused by calcium overload would help to research directly targeted therapeutic agents. We will specifically review the following: intracellular calcium homeostasis and regulation, the occurrence of calcium overload in acinar cells, the role of calcium overload in the pathogenesis of AP, the treatment strategy proposed for calcium overload.

Application of semi-automated ultrasonography on nutritional support for severe acute pancreatitis

OBJECTIVE

To evaluate the application value of semi-automated ultrasound on the guidance of nasogastrojejunal tube replacement for patients with acute severe pancreatitis (ASP), as well as the value of the nutritional support for standardized treatment in clinical practice.

METHODS

The retrospective research was performed in our hospital, and 34 patients suffering from ASP were enrolled into this study. All these identified participants ever received CT scans in order to make definitive diagnoses. Following, these patients received semi-automated ultrasound examinations within 1 days after their onset, in order to provide enteral nutrititon treatment via nasogastrojejunal tube, or freehand nasogastrojejunal tube replacement. In terms of statistical analysis, the application value of semi-automated ultrasound guidance on nasogastrojejunal tube replacement was evaluated, and was compared with tube replacement of no guidance. After cathetering, the additional enteral nutrition was provided, and its therapeutic effect on SAP was analyzed in further.

RESULTS

A total of 34 patients with pancreatitis were identified in this research, 29 cases with necrosis of pancreas parenchyma. After further examinations, 32 cases were SAP, 2 cases were mild acute pancreatitis. When the firm diagnosis was made, additional enteral nutrition (EN) was given, all the patient conditions appeared good, and they all were satisfied with this kind of nutritional support. According to our clinical experience, when there was 200-250 ml liquid in the stomach, the successful rate of intubation appeared higher. Additionally, the comparison between ultrasound-guided and freehand nasogastrojejunal tube replacement was made. According to the statistical results, in terms of the utilization ratio of nutritional support, it was better in ultrasound-guided group, when compared with it in freehand group, within 1 day, after 3 days and after 7 days (7/20 versus 2/14; P < 0.05; 14/20 versus 6/14; P < 0.05; 20/20 versus 12/14; P < 0.05). Besides, the complications caused by cathetering between two groups was not statistically different (P > 0.05).

CONCLUSIONS

It can be indicated that semi-automated ultrasound guidance is a reliable method for nasogastrojejunal tube replacement, and should be substituted for no guidance of cathetering. In terms of therapeutic effect of EN, additional nutritional support contributed to significantly improve the prognosis of SAP patients, and should be widely recommended in clinical practice. Surely, this conclusion should be evaluated in further, by means of randomized controlled trials and economic evaluation.

Inhibiting YAP expression suppresses pancreatic cancer progression by disrupting tumor-stromal interactions

Background

Hippo/YAP pathway is known to be important for development, growth and organogenesis, and dysregulation of this pathway leads to tumor progression. We and others find that YAP is up-regulated in pancreatic ductal adenocarcinoma (PDAC) and associated with worse prognosis of patients. Activated pancreatic stellate cells (PSCs) forming the components of microenvironment that enhance pancreatic cancer cells (PCs) invasiveness and malignance. However, the role and mechanism of YAP in PDAC tumor-stromal interaction is largely unknown.

Methods

The expression of YAP in Pancreatic cancer cell lines and PDAC samples was examined by Western blot and IHC. The biological role of YAP on cancer cell proliferation, epithelial-mesenchymal transition (EMT) and invasion were evaluated by MTT, Quantitative real-time PCR analysis, Western blot analysis and invasion assay. The effect of YAP on PSC activation was evaluated by PC-PSC co-culture conditions and xenograft PDAC mouse model.

Results

Firstly, knockdown of YAP inhibits PDAC cell proliferation and invasion in vitro. In addition, YAP modulates the PC and PSC interaction via reducing the production of connective tissue growth factor (CTGF) from PCs, inhibits paracrine-mediated PSC activation under PC-PSC co-culture conditions and in turn disrupts TGF-β1-mediated tumor-stromal interactions. Lastly, inhibiting YAP expression prevents tumor growth and suppresses desmoplastic reaction in vivo.

Conclusions

These results demonstrate that YAP contributes to the proliferation and invasion of PC and the activation of PSC via tumor-stromal interactions and that targeting YAP may be a promising therapeutic strategy for PDAC treatment.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0740-4) contains supplementary material, which is available to authorized users.

Potential of resveratrol in mitigating metabolic disturbances induced by ethanol

Alcohol abuse is associated with numerous health problems, including metabolic disturbances and liver damage. Therefore, different compounds are continuously being tested to evaluate their potential effectiveness in reducing these harmful changes. Animal studies clearly show that resveratrol is capable of ameliorating some consequences of ethanol ingestion. Resveratrol is a naturally occurring diphenolic compound having pleiotropic, health-promoting properties. Its beneficial action have been also demonstrated in animal models with ethanol-induced metabolic disturbances and liver injury. In ethanol treated animals, resveratrol effectively reduced liver lipid accumulation. Moreover, this compound diminished necrosis of hepatocytes, and also reduced liver fibrosis. The hepatoprotective action of resveratrol is largely associated with its ant-oxidant and anti-inflammatory properties, and also covers changes in activities of some enzymes. It is known that this compound upregulates the adiponectin-SIRT1-AMPK signaling pathway in the liver. Resveratrol was also found to positively affect blood lipids in animals exposed to ethanol. Moreover, administration of resveratrol to animals with ethanol-induced hypoinsulinemia and insulin resistance was shown to alleviate these disturbances. These outcomes clearly indicate that resveratrol holds great potential to reduce some consequences of ethanol ingestion. However, human studies are required to fully assess its therapeutic value.

Functional/activity network (FAN) analysis of gene-phenotype connectivity liaised by grape polyphenol resveratrol

Resveratrol is a polyphenol that has witnessed an unprecedented yearly growth in PubMed citations since the late 1990s. Based on the diversity of cellular processes and diseases resveratrol reportedly affects and benefits, it is likely that the interest in resveratrol will continue, although uncertainty regarding its mechanism in different biological systems remains.

We hypothesize that insights on disease-modulatory activities of resveratrol might be gleaned by systematically dissecting the publicly available published data on chemicals and drugs. In this study, we tested our hypothesis by querying DTome (Drug-Target Interactome), a web-based tool containing data compiled from open-source databases including DrugBank, PharmGSK, and Protein Interaction Network Analysis (PINA). Four direct protein targets (DPT) and 219 DPT-associated genes were identified for resveratrol. The DPT-associated genes were scrutinized by WebGestalt (WEB-based Gene SeT Analysis Toolkit). This enrichment analysis resulted in 10 identified KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways. Refined analysis of KEGG pathways showed that 2 — one linked to p53 and a second to prostate cancer — have functional connectivity to resveratrol and its four direct protein targets. These results suggest that a functional activity network (FAN) approach may be considered as a new paradigm for guiding future studies of resveratrol. FAN analysis resembles a BioGPS, with capability for mapping a Web-based scientific track that can productively and cost effectively connect resveratrol to its primary and secondary target proteins and to its biological functions.

Chinese Herbal Medicines Attenuate Acute Pancreatitis: Pharmacological Activities and Mechanisms

Acute pancreatitis (AP) is a commonly occurring gastrointestinal disorder. An increase in the annual incidence of AP has been observed, and it causes acute hospitalization and high mortality. The diagnosis and treatment guidelines for AP recommend conservative medical treatments focused on reducing pancreatic secretion and secondary injury, as a primary therapeutic approach. Unfortunately, the existing treatment options have limited impact on the incidence and severity of AP due to the complex and multifaceted pathological process of this disease. In recent decades, Chinese herbal medicines (CHMs) have been used as efficient therapeutic agents to attenuate AP in Asian countries. Despite early cell culture, animal models, and clinical trials, CHMs are capable of interacting with numerous molecular targets participating in the pathogenesis of AP; however, comprehensive, up-to-date communication in this field is not yet available. This review focuses on the pharmacological activities of CHMs against AP in vitro and in vivo and the underlying mechanisms. A computational prediction of few selected and promising plant-derived molecules (emodin, baicalin, resveratrol, curcumin, ligustrazine, and honokiol) to target numerous proteins or networks involved in AP was initially established based on a network pharmacology simulation. Moreover, we also summarized some potential toxic natural products for pancreas in order to more safe and reasonable medication. These breakthrough findings may have important implications for innovative drug research and the future development of treatments for AP.

Chronic Pancreatitis Associated Acute Respiratory Failure

Pancreatitis is a condition characterized by parenchymal inflammation of the pancreas, which is often associated with lung injury due to low level of oxygen and the condition is termed as acute pancreatitis-associated lung injury (APALI). Clinical reports indicated that ~ 20% to 50% of patients from low oxygen levels in blood with acute respiratory distress syndrome (ARDS). ARDS is a severe form of acute lung injury (ALI), a pulmonary disease with impaired airflow making patients difficult to breathe. ALI is frequently observed in patients with severe acute pancreatitis. Approximately one third of severe pancreatitis patients develop acute lung injury and acute respiratory distress syndrome that account for 60% of all deaths within the first week. The major causes of ALI and ARDS are sepsis, trauma, aspiration, multiple blood transfusion, and most importantly acute pancreatitis. The molecular mechanisms of ALI and ARDS are still not well explored, but available reports indicate the involvement of several pro-inflammatory mediators including cytokines (TNF-α, IL-1β, IL-6) and chemokines [like interleukin-8 (IL-8) and macrophage inhibitory factor (MIF)], as well as macrophage polarization regulating the migration and pulmonary infiltration of neutrophils into the pulmonary interstitial tissue, causing injury to the pulmonary parenchyma. Acute lung injury and acute respiratory distress syndrome in acute pancreatitis remains an unsolved issue and needs more research and resources to develop effective treatments and therapies. However, recent efforts have tested several molecules in an experimental model and showed promising results as a treatment option. The current review summarized the mechanism that is operational in pancreatitis-associated acute respiratory failure and respiratory distress syndrome in patients and current treatment options.

YAP Inhibition by Resveratrol via Activation of AMPK Enhances the Sensitivity of Pancreatic Cancer Cells to Gemcitabine

Resveratrol, a natural polyphenol present in most plants, inhibits the growth of numerous cancers both in vitro and in vivo. Aberrant expression of YAP has been reported to activate multiple growth-regulatory pathways and confer anti-apoptotic abilities to many cancer cells. However, the role of resveratrol in YES-activated protein (YAP) expression and that of YAP in pancreatic cancer cells’ response to gemcitabine resistance remain elusive. In this study, we found that resveratrol suppressed the proliferation and cloning ability and induced the apoptosis of pancreatic cancer cells. These multiple biological effects might result from the activation of AMP-activation protein kinase (AMPK) (Thr172) and, thus, the induction of YAP cytoplasmic retention, Ser127 phosphorylation, and the inhibition of YAP transcriptional activity by resveratrol. YAP silencing by siRNA or resveratrol enhanced the sensitivity of gemcitabine in pancreatic cancer cells. Taken together, these findings demonstrate that resveratrol could increase the sensitivity of pancreatic cancer cells to gemcitabine by inhibiting YAP expression. More importantly, our work reveals that resveratrol is a potential anticancer agent for the treatment of pancreatic cancer, and YAP may serve as a promising target for sensitizing pancreatic cancer cells to chemotherapy.

Mechanisms of action of emodin and resveratrol in severe acute pancreatitis: A comparison

Acute pancreatitis (AP) is a common acute abdominal disease, and 20% of AP cases progress to severe acute pancreatitis (SAP). Current studies have found that pancreatic microcirculation disturbance, leukocyte over-activation, inflammatory mediator overexpression, cell apoptosis disorders in damaged tissue, and calcium overload play important roles in SAP progression. Numerous studies have shown that traditional Chinese medicine (TCM) has a protective effect on SAP. In recent ten years, emodin and resveratrol are hot spot in the field of research on the treatment of SAP animal models with TCM. This review attempts to illuminate and compare the potential mechanisms of action of emodin and resveratrol in SAP from the perspective of traditional Chinese pharmacology and modern pharmacology.

Correlation between expression of 1 α -hydroxylase and hypocalcaemia in rats with severe pancreatitis

OBJECTIVE

To investigate the essential biochemical indices like 1 -hydroxylase and hypocalcaemia in the rats with severe acute pancreatitis and explore the correlation between them.

METHODS

A total of 120 SPF grade Wistar male rats which were in similar physiological status were selected and randomly divided into two groups: sham group (SO group) and severe acute pancreatitis group (SAP group). Then they were divided into 1 h, 3 h, 6 h, and 12 h subgroups according to the killing time. The severe acute pancreatitis model was established by retrograde injection of 5% sodium taurocholate. Serum calcium, serum creatinine, serum urea nitrogen and serum amylase were measured at different time. Serum 1, 25 dihydroxy vitamin D3 level was determined by enzyme linked immunosorbentassay. The expression of 1-hydroxylase protein in the kidney tissue was determined with Western blotting and immunohistochemistry to observe its location. The pathologic features of the kidney tissue section was observed under light microscope and submicroscopic structure of the proximal convoluted tubule epithelial cell was observed under transmission electron microscope.

RESULTS

Compared with the SO group, rats in the SAP group showed continuous pathological injury as time went by. There was significant increase in serum creatinine, serum urea nitrogen and serum amylase in SAP group compared with the SO group 1, 3, 6, 12 hours after the operation (P<0.05). There was significant decrease in serum calcium and 1, 25 dihydroxy vitamin D3 3, 6, 12 hours after the operation (P<0.05). It also showed that the expression of the 1-hydroxylase protein in kidney tissues was upregulated at 1 h, 3 h and decreased at 6 h, 12 h compared with the SO group. The serum calcium, 1, 25 dihydroxy vitamin D3 and the expression of the 1-hydroxylase protein in kidney tissues of the SAP group showed sustaining decrease. Western blotting showed positive correlation between the 1-hydroxylase expression and serum calcium at 3 h, 6 h and 12 h (r=0.976, P<0.001; r=0.948, P<0.001; r=0.742, P=0.001) and also positive correlation between the 1-hydroxylase expression and serum 1, 25 dihydroxy vitamin D3 at 1 h, 3 h, 6 h and 12 h (r=0.935, P<0.001; r=0.952, P<0.001; r=0.917, P<0.001; r=0.874, P<0.001).

CONCLUSIONS

At the early stage of the kidney injury, the expression of 1-hydroxylase in the kidney tissue is reduced with the progress of the disease and the decrease in its activity has a correlation with the hypocalcaemia.

Antioxidative phytoceuticals to ameliorate pancreatitis in animal models: An answer from nature

Despite enthusiastic efforts directed at elucidating critical underlying mechanisms towards the identification of novel therapeutic targets for severe acute pancreatitis (SAP), the disease remains without a specific therapy to be executed within the first hours to days after onset of symptoms. Although earlier management for SAP should aim to either treat organ failure or reduce infectious complications, the current standard of care for the general management of AP in the first hours to days after onset of symptoms include intravenous fluid replacement, nutritional changes, and the use of analgesics with a close monitoring of vital signs. Furthermore, repeated evaluation of severity is very important, as the condition is particularly unstable in the early stages. In cases where biliary pancreatitis is accompanied by acute cholangitis or in cases where biliary stasis is suspected, an early endoscopic retrograde cholangiopancreatography is recommended. However, practice guidelines regarding the treatment of pancreatitis are suboptimal. In chronic pancreatitis, conservative management strategies include lifestyle modifications and dietary changes followed by analgesics and pancreatic enzyme supplementation. Recently, attention has been focused on phytoceuticals or antioxidants as agents that could surpass the limitations associated with currently available therapies. Because oxidative stress has been shown to play an important role in the pathogenesis of pancreatitis, antioxidants alone or combined with conventional therapy may improve oxidative-stress-induced organ damage. Interest in phytoceuticals stems from their potential use as simple, accurate tools for pancreatitis prognostication that could replace older and more tedious methods. Therefore, the use of antioxidative nutrition or phytoceuticals may represent a new direction for clinical research in pancreatitis. In this review article, recent advances in the understanding of the pathogenesis of pancreatitis are discussed and the paradigm shift underway to develop phytoceuticals and antioxidants to treat it is introduced. Despite the promise of studies evaluating the effects of antioxidants/phytoceuticals in pancreatitis, translation to the clinic has thus far been disappointing. However, it is expected that continued research will provide solid evidence to justify the use of antioxidative phytoceuticals in the treatment of pancreatitis.

Resveratrol stimulates AP-1-regulated gene transcription

SCOPE

Many intracellular functions have been attributed to resveratrol, a polyphenolic phytoalexin found in grapes and in other plants, including the regulation of transcription. Here, we have analyzed the impact of resveratrol on the activity of the transcription factor activator protein-1 (AP-1).

METHODS AND RESULTS

Using a chromosomally embedded AP-1-responsive reporter gene, we show that the AP-1 activity was significantly elevated in resveratrol-treated 293 human embryonic kidney and HepG2 hepatoma cells. The 12-O-tetradecanoylphorbol-13-acetate-responsive element, a binding site for c-Jun and c-Fos, was identified as resveratrol-responsive element. Expression of c-Jun and c-Fos, two proteins that constitute AP-1, is upregulated in resveratrol-stimulated HEK293 cells. On the transcriptional level, c-Jun and the ternary complex factor Elk-1 are essential for the activation of AP-1 in resveratrol-treated cells. In addition, mitogen-activated protein kinases and protein kinase C are required to connect resveratrol stimulation with enhanced AP-1 controlled transcription. Finally, we show that resveratrol increased the activities of the AP-1 responsive cyclin D1 and tumor necrosis factor α promoters.

CONCLUSION

Resveratrol regulates gene transcription via activation of stimulus-regulated protein kinases and the stimulus-responsive AP-1 transcription factors. The fact that resveratrol regulates AP-1 activity may explain many of the pleiotropic intracellular alterations induced by resveratrol.

Chemopreventive effects of resveratrol in a rat model of cerulein-induced acute pancreatitis

In the past decades, a greater understanding of acute pancreatitis has led to improvement in mortality rates. Nevertheless, this disease continues to be a health care system problem due to its economical costs. Future strategies such as antioxidant supplementation could be very promising, regarding to beginning and progression of the disease. For this reason, this study was aimed at assessing the effect of exogenous administration of resveratrol during the induction process of acute pancreatitis caused by the cholecystokinin analog cerulein in rats. Resveratrol pretreatment reduced histological damage induced by cerulein treatment, as well as hyperamylasemia and hyperlipidemia. Altered levels of corticosterone, total antioxidant status, and glutathione peroxidase were significantly reverted to control levels by the administration of resveratrol. Lipid peroxidation was also counteracted; nevertheless, superoxide dismutase enzyme was overexpressed due to resveratrol pretreatment. Related to immune response, resveratrol pretreatment reduced pro-inflammatory cytokine IL-1β levels and increased anti-inflammatory cytokine IL-10 levels. In addition, pretreatment with resveratrol in cerulein-induced pancreatitis rats was able to reverse, at least partially, the abnormal calcium signal induced by treatment with cerulein. In conclusion, this study confirms antioxidant and immunomodulatory properties of resveratrol as chemopreventive in cerulein-induced acute pancreatitis.

Protective effects of saizen in combination with stilamin on intestinal mucosa of a rabbit model of severe acute pancreatitis

OBJECTIVES

The objective of this study was to investigate whether the regimen of saizen, a recombinant human somatropin, in combination stilamin, a somatostatin analog, exerts synergistic effect on intestinal mucosa of a rabbit model of severe acute pancreatitis.

METHODS

The rabbits were randomly divided into 3 groups: group A without any treatment, group B with single treatment of stilamin, and group C with treatment of saizen combined with stilamin. The blood levels of D-lactate, insulinlike growth factor 1, prealbumin, and albumin were detected at the 6th, 12th, 24th, 48th, and 72nd hours after modeling. The pathological changes in terms of the villus height, crypt depth, and mucosal thickness were observed. The caspase 3 expression and apoptotic indices were evaluated.

RESULTS

The blood levels of D-lactate at the 48th hour; insulinlike growth factor 1 at the 24th and 48th hours; prealbumin at the 24th, 48th, and 72nd hours; and albumin at the 48th hour in group C were significantly higher than these in the other 2 groups. Pathological changes in group C were slighter; the level of caspase 3 and apoptotic index in group C were significantly lower than those in the other 2 groups.

CONCLUSIONS

The combination of saizen with stilamin can enhance intestinal mucosa barrier function.

Experimental and clinical evidence of antioxidant therapy in acute pancreatitis

Oxidative stress has been shown to play an important role in the pathogenesis of acute pancreatitis (AP). Antioxidants, alone or in combination with conventional therapy, should improve oxidative-stress-induced organ damage and therefore accelerate the rate of recovery. In recent years, substantial amounts of data about the efficiency of antioxidants against oxidative damage have been obtained from experiments with rodents. Some of these antioxidants have been found beneficial in the treatment of AP in humans; however, at present there is insufficient clinical data to support the benefits of antioxidants, alone or in combination with conventional therapy, in the management of AP in humans. Conflicting results obtained from experimental animals and humans may represent distinct pathophysiological mechanisms mediating tissue injury in different species. Further detailed studies should be done to clarify the exact mechanisms of tissue injury in human AP. Herein I tried to review the existing experimental and clinical studies on AP in order to determine the efficiency of antioxidants. The use of antioxidant enriched nutrition is a potential direction of clinical research in AP given the lack of clues about the efficiency and safety of antioxidant usage in patients with AP.

Resveratrol mobilizes Ca2+ from intracellular stores and induces c-Jun N-terminal kinase activation in tumoral AR42J cells

Resveratrol (3,4',5-trihydroxy-trans-stilbene), a phytoalexin naturally found in grapes and red wine, is a redox-active compound endowed with significant positive activities. In this study, the effects of resveratrol on intracellular free Ca(2+) concentration ([Ca(2+)](c)) and on cell viability in tumoral AR42J pancreatic cells are examined. The results show that resveratrol (100 μM and 1 mM) induced changes in [Ca(2+)](c), that consisted of single or short lasting spikes followed by a slow reduction toward a value close to the resting level. Lower concentrations of resveratrol (1 and 10 μM) did not show detectable effects on [Ca(2+)](c). Depletion of intracellular Ca(2+) stores by stimulation of cells with 1 nM CCK-8, 20 pM CCK-8 or 1 μM thapsigargin, blocked Ca(2+) responses evoked by resveratrol. Conversely, prior stimulation of cells with resveratrol inhibited Ca(2+) mobilization in response to a secondary application of CCK-8 or thapsigargin. In addition, resveratrol inhibited oscillations in [Ca(2+)](c) evoked by a physiological concentration of CCK-8 (20 pM). On the other hand, incubation of cells in the presence of resveratrol induced a reduction of cell viability. Finally, incubation of AR42J cells in the presence of resveratrol led to activation of c-Jun N-terminal kinase (JNK), a mitogen-activated protein kinase responsive to stress stimuli. Activation of JNK was reduced in the absence of extracellular Ca(2+). In summary, the results show that resveratrol releases Ca(2+) from intracellular stores, most probably from the endoplasmic reticulum, and reduces AR42J cells viability. Reorganization of cell's survival/death processes in the presence of resveratrol may involve Ca(2+)-mediated JNK activation.

Molecular mechanisms of pancreatic injury

PURPOSE OF REVIEW

Despite being a subject of much scientific scrutiny, the pathogenesis of acute pancreatitis is still not well understood. This article reviews recent advances in our understanding of acute pancreatitis.

RECENT FINDINGS

Zymogen activation, observed within acini early during acute pancreatitis for a long time, was shown to be sufficient to induce acute pancreatitis. Another key early event, NFκB activation, has previously been shown to induce acute pancreatitis. The relationship between these two key early steps is beginning to be clarified. Mechanisms of zymogen activation - pathologic calcium signaling, pH changes, colocalization and autophagy, and of NFκB activation have been investigated intensively along with potential therapeutic targets both upstream and downstream of these key events. Additional key findings have been elucidation of the role of bioenergetics and the dual role of oxidative stress in acute pancreatitis, recognition of endoplasmic reticulum stress as an early step and the status of duct cells as important entities in pancreatic injury.

SUMMARY

Current findings have provided further insight into the roles and mechanisms of zymogen activation and inflammatory pathways in pancreatic injury. Future studies, which will be of great importance in identifying therapeutic targets, are being undertaken to establish the relative contributions of these pathways during acute pancreatitis.