Effects of trimetazidine in acute pancreatitis induced by L-arginine

An open-label Phase 2a study to assess the safety and tolerability of trimetazidine in patients with amyotrophic lateral sclerosis

Metabolic imbalance is associated with amyotrophic lateral sclerosis progression. Impaired glucose oxidation and increased reliance on fatty acid oxidation contribute to reduced metabolic flexibility and faster disease progression in amyotrophic lateral sclerosis. We sought to evaluate the safety and tolerability, and explore the pharmacodynamic response of trimetazidine, a partial fatty acid oxidation inhibitor, on oxidative stress markers and energy expenditure in amyotrophic lateral sclerosis. The study was conducted between June 29, 2021 and May 24, 2023. People living with amyotrophic lateral sclerosis, recruited in Australia and the Netherlands, received open-label oral trimetazidine for 12 weeks after an initial 4-week lead-in period. The primary outcome measures were safety and tolerability, as well as the change from baseline in oxidative stress markers malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Secondary outcome measures were change from baseline in energy expenditure, amyotrophic lateral sclerosis functional rating scale-revised, and slow vital capacity (SVC). Linear mixed effects were used to estimate the mean difference in MDA and 8-OHdG between the on- and off-treatment periods. This trial is registered under ClinicalTrial.gov National Clinical Trial (NCT) number NCT04788745 and European Union Drug Regulating Authorities Clinical Trials (EudraCT) number 2020-005018-17. Twenty-one participants received trimetazidine; 19 (90%) completed the treatment period. Trimetazidine was well tolerated; there were 57 adverse events reported, of which 7 (11%) were deemed potentially drug-related, including hot flushes (2), nausea (2), paraesthesia (2) and fatigue (1). MDA was numerically lower during treatment [-0.29 uM; 95% confidence interval (CI) -0.90 to 0.33, P  = 0.36]; 8-OHdG was significantly lower during treatment (-0.12 nM; 95% CI -0.23 to -0.01, P = 0.0245). The decrease in oxidative stress markers was accompanied by a reduction in resting energy expenditure (95 kcal, 95% CI 36.8-154, P = 0.0014). The absence of a placebo group prevented the interpretation of the clinical parameters. Oral trimetazidine was safe and well tolerated among patients with amyotrophic lateral sclerosis. This, combined with the significant reduction in markers of oxidative stress and resting energy expenditure, warrants a larger double-blind placebo-controlled efficacy study.

New insights on pharmacological and therapeutic potentials of trimetazidine beyond anti-anginal drug: A comprehensive review

Trimetazidine (TMZ) is a beneficial and well-tolerable anti-anginal drug which has protective action towards ischemia and reperfusion injury. TMZ performs its anti-ischemic effect by modifying cardiac metabolism without shifting the hemodynamic functions, so it represents an outstanding complementary perspective to the general angina treatment. TMZ possesses a positive impact on the inflammatory profile, and also endothelial function furthermore displays various benefits through minimising the number, as well as the intensity of angina strikes and ameliorating the clinical indication and symptoms of myocardium ischemia. It is administrated as monotherapy along with a combination of different antianginal drugs. Apart from anti-angina action, in recent years TMZ has shown various pharmacological activities such as neuroprotective, renal protective, hepato-protective, cardio-protective effects, and other beneficial pharmacological activities. We select to write the present review article to cover the different pharmacological and therapeutic potentials of TMZ.

Pinocembrin's protective effect against acute pancreatitis in a rat model: The correlation between TLR4/NF-κB/NLRP3 and miR-34a-5p/SIRT1/Nrf2/HO-1 pathways

BACKGROUND

Acute pancreatitis (APS) is a prevalent acute pancreatic inflammation, where oxidative stress, inflammatory signaling pathways, and apoptosis activation contribute to pancreatic injury.

METHODS

Pinocembrin, the predominant flavonoid in propolis, was explored for its likely shielding effect against APS provoked by two intraperitoneal doses of L-arginine (250 mg / 100 g) in a rat model.

RESULTS

Pinocembrin ameliorated the histological and immunohistochemical changes in pancreatic tissues and lowered the activities of pancreatic amylase and lipase that were markedly elevated with L-arginine administration. Moreover, pinocembrin reinstated the oxidant/antioxidant equilibrium, which was perturbed by L-arginine, and boosted the pancreatic levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Pinocembrin markedly reduced the elevation in serum C-reactive protein (CRP) level induced by L-arginine. Additionally, it decreased the expression of high motility group box protein 1 (HMGB1), toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and NOD-like receptor (NLR) Family Pyrin Domain Containing 3 (NLRP3) inflammasome in the pancreas. Furthermore, it also reduced myeloperoxidase (MPO) activity. Pinocembrin markedly downregulated miR-34a-5p expression and upregulated the protein levels of peroxisome proliferator-activated receptor alpha (PPAR-α) and Sirtuin 1 (SIRT1) and the gene expression level of the inhibitor protein of NF-κB (IκB-α), along with normalizing the Bax/Bcl-2 ratio.

CONCLUSIONS

Pinocembrin notably improved L-arginine-induced APS by its antioxidant, anti-inflammatory, and anti-apoptotic activities. Pinocembrin exhibited a protective role in APS by suppressing inflammatory signaling via the TLR4/NF-κB/NLRP3 pathway and enhancing cytoprotective signaling via the miR-34a-5p/SIRT1/Nrf2/HO-1 pathway.

Sitagliptin ameliorates L-arginine-induced acute pancreatitis via modulating inflammatory cytokines expression and combating oxidative stress

Background

Acute pancreatitis (AP) is an inflammatory condition that resolves spontaneously, but occasionally, develops into systemic inflammation, organ failure and mortality. Oxidative stress and activation of inflammatory pathways represent major players in AP pathogenesis. Current management of AP relies on attenuating injuries to the pancreas and putting the inflammatory process under control. In this study, we investigated the role of sitagliptin in modulating L-arginine-induced AP in rats.

Methods

Swiss rats were subdivided into a healthy control group, AP group (a single dose of L-arginine 250 mg/100 g, intraperitoneal), and sitagliptin + L-arginine-treated group (10 mg sitagliptin/kg body weight/day, orally). Sitagliptin treatment started 1 hour after L-arginine injection and continued for 3days. Biochemical and histopathological investigations were performed on serum and tissue samples collected from test animals.

Results

L-arginine increased pancreatic meyloperoxidase and serum amylase- and lipase activities and serum levels of TNF-α, LT-α, IFN-γ, IL-1α/β, IL-6, IL-10, IL-12, and IL-15. AP animals showed elevated MDA and NO and decreased GSH and serum calcium levels. Histopathological changes were observed by H&E staining. Sitagliptin treatment significantly ameliorated these biochemical and histological changes diminishing the signs of AP.

Conclusion

Sitagliptin treatment was effective in ameliorating L-arginine-induced AP which can be regarded to its anti-inflammatory and antioxidant effect.

Sodium pyruvate improves the plasma amino acid profile in rats with L-arginine-induced acute pancreatitis

Plasma amino acid levels are altered upon many pathological conditions including acute pancreatitis. It is unclear whether amino acids can be used as specific biomarker of acute pancreatitis severity or recovery. Development of acute pancreatitis is associated with mitochondrial dysfunction and decreased cytosolic ATP level. Sodium pyruvate is considered as a potential treatment of pancreatitis due to its ability to sustain mitochondrial oxidative and ATP-productive capacity in vitro. This study investigated the effect of sodium pyruvate on pancreatic morphology and plasma amino acid levels in rats with acute pancreatitis. Acute pancreatitis in rats was induced by administration of L-arginine (5 g/kg) Experimental treatment group received sodium pyruvate (1 g/kg) for 4 days. On day 8 of the experiment, animals were killed, blood was collected and plasma amino acid concentration was determined with high-performance liquid chromatography. Histological examination showed large areas of fibrosis in the pancreas of animals treated with L-arginine irrespectively of sodium pyruvate administration. Sodium pyruvate improved the plasma amino acid levels. Rats with acute pancreatitis had significantly lower levels of most essential and non-essential amino acids and increased glutamate and aspartate in plasma. Administration of sodium pyruvate completely or partially restored the levels of methionine, phenylalanine, tryptophan, leucine, isoleucine, aspartate, asparagine and ornithine levels, while increasing glutamine and serine to levels significantly higher than control. Plasma lysine, alanine, arginine and taurine remained unaffected in all experimental groups. Sodium pyruvate may be considered for use as a maintenance therapy in acute pancreatitis.

Genistein attenuated oxidative stress, inflammation, and apoptosis in L-arginine induced acute pancreatitis in mice

Aim

Acute pancreatitis is a common and potentially serious condition. However, a specific treatment for this condition is still lacking. Genistein, with its anti-oxidant and anti-inflammatory effects, could possibly be used to tackle the underlying pathophysiology of acute pancreatitis. Therefore, the aim of this study was to investigate the effects of genistein on oxidative stress, inflammation, and apoptosis in acute pancreatitis induced by L-arginine in mice.

Methods

Twenty-four male ICR mice were equally divided into 4 groups: Control (Con); Acute pancreatitis (AP) group: Two doses of i.p. 350 mg/100 g body weight (BW) of L-arginine were administered 1 h apart; AP and low-dose genistein (LG) group: mice were given i.p. injection of 10 mg/kg genistein 2 h prior to L-arginine injection followed by once-daily dosing for 3 days; and AP and high-dose genistein (HG) group: mice were given 100 mg/kg genistein with the similar protocol as the LG group. Pancreatic tissue was evaluated for histopathological changes and acinar cell apoptosis, malondialdehyde (MDA) levels, immunohistochemical staining for myeloperoxidase (MPO), nuclear factor-kappa beta (NF-kB), and 4-hydroxynonenal (4-HNE). Serum levels of amylase (AMY), c-reactive protein (CRP), and interleukin (IL)-6 were measured.

Results

Significant increases in the degree of acinar cell apoptosis, pancreatic MDA, serum IL-6 and amylase, MPO, NF-kB and 4-HNE positivity were observed in the AP group. All these parameters declined after low- and high-dose genistein treatment. Severe pancreatic inflammation, edema, and acinar cell necrosis were observed in the AP group. Significant improvement of histopathological changes was seen in both low- and high-dose genistein groups. There were no significant differences in any parameters between low and high doses of genistein.

Conclusion

Genistein could attenuate the severity of histopathological changes in acute pancreatitis through its anti-oxidant, anti-inflammatory, and anti-apoptotic properties.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03689-9.

The protective effects of trimetazidine against ovary ischemia-reperfusion injury via the TLR4/Nf-kB signal pathway

Late diagnosis and treatment of ovarian ischemia can lead to worsening of ischemia, irreversible damage to ovarian functions and infertility. In this process, there is no approved medical treatment that can reduce the negative effects of ischemia and contribute positively to ovarian functions during reperfusion after detorsion. Rats were randomly assigned into one of six groups of eight animals each. The groups were designed as follows: The control group, The ischemia(I) group, The Ischemia + Trimetazidine (I + TMZ) (20 mg/kg) group, and The ischemia-reperfusion group (I/R). The Ischemia-Reperfusion + Trimetazidine (I/R + TMZ) (20 mg/kg) group, and The Sham + Trimetazidine (Sham + TMZ) (20 mg/kg) group. In this study performed thiobarbituric acid reactive substances (TBARS), total thiol (-SH), interleukin 1 beta (IL-1β), interleukin 6 (IL-6), toll-like receptor 4 (TLR4), and nuclear factor-kappa B(NF-κβ). Increased oxidative stress and inflammation were as a result of ovarian I and I/R application. Trimetazidine (TMZ), was sufficient to reduce the oxidative stress and inflammation. TLR4 and NF-κβ, which were upregulated by oxidative stress and inflammation, were regressed by TMZ. TMZ should be considered as a potential therapeutic agent in addition to surgery in the clinical treatment of ovarian torsion.

Trimetazidine alone or in combination with gemcitabine and/or abraxane decreased cell viability, migration and ATP levels and induced apoptosis of human pancreatic cells

BACKGROUND

Trimetazidine (TMZ) is an anti-ischemic agent that can inhibit the fatty acid oxidation. It has been stated that inhibition of fatty acid oxidation may be an acceptable approach to cancer treatment.

METHODS

We examined the effects of TMZ alone or together with abraxane (ABX) and/or gemcitabine (GEM) on cell viability, apoptosis, adhesion, migration and ATP levels of human pancreatic cancer cell line PANC-1.

RESULTS

TMZ significantly reduced the cell viability at higher concentrations. Lower cell viability values were found in cells co-treated with TMZ + GEM, TMZ + ABX and GEM + ABX. The combined treatment of TMZ with ABX and/or GEM significantly increased the apoptosis rates. The highest percentages of apoptosis were found in TMZ + ABX or TMZ + ABX + GEM treatments. TMZ alone or together with ABX and/or GEM significantly reduced the ATP levels. The lowest migration rates were also found at TMZ + ABX and TMZ + ABX + GEM treatments.

CONCLUSIONS

Our study is the first study to indicate that TMZ can induce cytotoxicity and apoptosis and reduce migration and ATP levels, especially in cells co-treated with ABX and/or GEM. A combination strategy based on inhibition of fatty acid oxidation and anticancer drugs may be more effective in the treatment of pancreatic cancers.

The effect of trimethazidine on mortality in an experimental acute pancreatitis model1

BACKGROUND/AIMS

Acute pancreatitis has a high morbidty and mortality. Its physiopathogenesis has not been enlightened up to the present. This study aims to investigate trimetazidine (antiischemic, antioxidant and cardioprotective agent) 's effects on the acute pancreatitis.

MATERIALS AND METHODS

In this study, four aqual groups are formed with 43 female Spraque-dawley type rats weighed between230-300 gr (mean 265 gr). 0.9% NaCl is injected intraperitoneally after laparotomy to the Group 1 (n=6). Group 2 (n=6) is control group that without any intervention. Acute pancreatitis is formed in Group 3 (n=16) via injection of Na-taurokolat in the common bile duct. Group 4 (n=15) is being formed pancreatitis and treated with Trimetazidine. In group 4 Trimetazidine 10 mg/kg/day drugs were given, 30 minutes, 24 and 72 hours after formation of acute pancreatitis, in three equal doses by orogastric way. In all groups, the rats have been laparatomised 72 hours later under general anesthesia and pancreas tissues has been extracted and studied histopathologically. Amylase, lipase, lactate dehydrogenase, aspartate transaminase, alanine tranaminase levels in the rats serum and superoxide dismutase, catalase, glutathione, malondialdehyde, nitric oxide, protein carbonyl, glutathione peroxidase levels in the rats tissue also have been looked up.

RESULTS

Serum and tissue findings and histopathologically examination of the pancreas tissues show significant decrease in the treatment group compare to study group.

CONCLUSION

Trimetazidine protects pancreas tissue and decreases the mortality by significantly lowering the biochemical and histopathological changes in the early stages of acute pancreatitis.

Comparing the preventive effect of sodium hydrosulfide, leptin, and curcumin against L-arginine induced acute pancreatitis in rats: role of corticosterone and inducible nitric oxide synthase

OBJECTIVES

Acute pancreatitis (AP) is a life-threatening condition. Using antioxidants in AP is insufficient and conflicting. Therefore, this study compared the effect of hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS), leptin or curcumin pretreatment on AP induced by L-arginine.

METHODS

Forty adult male rats were used and classified into: 1) control; 2) AP group [each rat was intraperitoneally (i.p.) injected with 2 doses of L-arginine of 250 mg/100 g body weight (b.w.) with an interval of 1 h]; 3) NaHS+AP group (each rat was i.p. injected with 10 mg/kg b.w. of NaHS 1 h before induction of AP); 4) leptin+AP group (each rat was pretreated with 10 μg/kg b.w. of leptin 30 min before induction of AP; and 5) curcumin+AP group (in which rats were i.p. injected with 150 mg/kg b.w. of curcumin 30 min before induction of AP). Serum amylase, lipase, nitric oxide (NO), tumor necrosis factor alpha (TNF-α), and corticosterone (CORT) levels were assayed. In addition, pancreatic tissues were obtained for histopathological examination and malondialde-hyde (MDA), total antioxidant capacity (TAC), and inducible nitric oxide synthase (iNOS) levels were measured.

RESULTS

All AP treated groups showed significant decrease in serum levels of pancreatic enzymes, NO, and TNF-α, and pancreatic MDA and iNOS levels, while TAC levels were significantly increased. NaHS caused more limitation of inflammation than leptin and curcumin by affecting iNOS. Leptin was more potent than curcumin due to the stimulatory effect of leptin on glucocorticoid release to counteract inflammation.

CONCLUSIONS

NaHS was more effective in AP amelioration than the leptin and curcumin.

Vaccinium macrocarpon Aiton Extract Ameliorates Inflammation and Hyperalgesia through Oxidative Stress Inhibition in Experimental Acute Pancreatitis

We evaluated the effect of the hydroethanolic extract of fruits of Vaccinium macrocarpon (HEVm) in a model of acute pancreatitis (AP) in mice. AP was induced by two injections of L-arginine and animals were treated with HEVm (50, 100, and 200 mg/kg, p.o.) or vehicle (saline) every 24 h, starting 1 h after the induction of AP. Phytochemical analysis of the extract and measurement of inflammatory and oxidative stress parameters, as well as abdominal hyperalgesia, were performed. Catechin, epicatechin, rutin, and anthocyanins were identified in HEVm. Treatment with HEVm decreased L-arginine-induced abdominal hyperalgesia (from 48 to 72 h). Also, treatment with HEVm decreased L-arginine-induced pancreatic edema, pancreatic and pulmonary neutrophil infiltration, and levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6, after 72 h of induction. L-arginine-induced hyperamylasemia and hyperlipasemia were also reduced by the treatment with HEVm in comparison to vehicle-treated group. Moreover, lipoperoxidation, carbonyl radicals, nonprotein sulfhydryl groups, and activity of catalase and superoxide dismutase, but not glutathione peroxidase, were restored by the treatment with HEVm. These results show that treatment with HEVm decreased hyperalgesia and pancreatic/extrapancreatic inflammation and oxidative damage in L-arginine-induced AP, making this extract attractive for future approaches designed to treat this condition.

Trimetazidine Increases Cell Survival and Inhibits the Activation of Inflammatory Response in Sodium Taurocholate–Induced Acute Pancreatitis

Objective:

To evaluate the therapeutic effects of trimetazidine (TMZ) in an experimental acute pancreatitis (AP) model induced with sodium taurocholate (STC).

Summary of Background Data:

At present, AP is considered a disease with no specific treatment. Preventing mitochondrial dysfunction in acinar cells may be an option for specific treatment of AP. TMZ is an anti-ischemic drug with anti-inflammatory, antioxidant, and mitochondrial modulatory effects.

Methods:

Rats were divided into 4 groups. AP was induced in the AP (n = 7) and AP + TMZ (n = 7) groups by an injection of 4% sodium taurocholate to the pancreatic duct. The sham (n = 6) and drug (n = 6) groups were designated as control groups. The AP + TMZ and drug groups were administered TMZ. Samples were taken at 72 hours, and histopathologic changes as well as biochemical parameters were analyzed.

Results:

Serum amylase, tissue myeloperoxidase activity, malondialdehyde levels, serum cytokine levels, and mast cell degranulation rates were elevated after induction of AP, whereas tissue antioxidant enzyme activities and cell viability rates [determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay] decreased. These parameters were found to be different in the AP group compared with those in all other groups (P < 0.05). A significant improvement of all parameters was achieved with the TMZ treatment of AP. Histologically, significant differences were found between the AP and AP + TMZ groups in terms of leukocyte infiltration, necrosis, and apoptotic cell counts.

Conclusions:

In this study, we demonstrated that TMZ treatment protected the mitochondrial function and prevented the activation of the inflammatory cascade in the sodium taurocholate–induced AP model.

Context-Dependent Epigenetic Regulation of Nuclear Factor of Activated T Cells 1 in Pancreatic Plasticity

BACKGROUND & AIMS

The ability of exocrine pancreatic cells to change the cellular phenotype is required for tissue regeneration upon injury, but also contributes to their malignant transformation and tumor progression. We investigated context-dependent signaling and transcription mechanisms that determine pancreatic cell fate decisions toward regeneration and malignancy. In particular, we studied the function and regulation of the inflammatory transcription factor nuclear factor of activated T cells 1 (NFATC1) in pancreatic cell plasticity and tissue adaptation.

METHODS

We analyzed cell plasticity during pancreatic regeneration and transformation in mice with pancreas-specific expression of a constitutively active form of NFATC1, or depletion of enhancer of zeste 2 homologue 2 (EZH2), in the context of wild-type or constitutively activate Kras, respectively. Acute and chronic pancreatitis were induced by intraperitoneal injection of caerulein. EZH2-dependent regulation of NFATC1 expression was studied in mouse in human pancreatic tissue and cells by immunohistochemistry, immunoblotting, and quantitative reverse transcription polymerase chain reaction. We used genetic and pharmacologic approaches of EZH2 and NFATC1 inhibition to study the consequences of pathway disruption on pancreatic morphology and function. Epigenetic modifications on the NFATC1 gene were investigated by chromatin immunoprecipitation assays.

RESULTS

NFATC1 was rapidly and transiently induced in early adaptation to acinar cell injury in human samples and in mice, where it promoted acinar cell transdifferentiation and blocked proliferation of metaplastic pancreatic cells. However, in late stages of regeneration, Nfatc1 was epigenetically silenced by EZH2-dependent histone methylation, to enable acinar cell redifferentiation and prevent organ atrophy and exocrine insufficiency. In contrast, oncogenic activation of KRAS signaling in pancreatic ductal adenocarcinoma cells reversed the EZH2-dependent effects on the NFATC1 gene and was required for EZH2-mediated transcriptional activation of NFATC1.

CONCLUSIONS

In studies of human and mouse pancreatic cells and tissue, we identified context-specific epigenetic regulation of NFATc1 activity as an important mechanism of pancreatic cell plasticity. Inhibitors of EZH2 might therefore interfere with oncogenic activity of NFATC1 and be used in treatment of pancreatic ductal adenocarcinoma.

Eff ects of hemin, a heme oxygenase-1 inducer in L-arginine-induced acute pancreatitis and associated lung injury in adult male albino rats

Objective. The aim of the current study was to assess the protective outcome of hemin, a heme oxygenase-1 (HO-1) inducer on L-arginine-induced acute pancreatitis in rats. Acute pancreatitis (AP) is considered to be a critical inflammatory disorder with a major impact on the patient health. Various theories have been recommended regarding the pathophysiology of AP and associated pulmonary complications.

Methods. Twenty-four adult male albino rats were randomly divided into four groups: control group, acute pancreatitis (AP), hemin pre-treated AP group, and hemin post-treated AP group.

Results. Administration of hemin before induction of AP significantly attenuated the L-arginine- induced pancreatitis and associated pulmonary complications characterized by the increasing serum levels of amylase, lipase, tumor necrosis factor-α, nitric oxide, and histo-architectural changes in pancreas and lungs as compared to control group. Additionally, pre-treatment with hemin significantly compensated the deficits in total antioxidant capacities and lowered the elevated malondialdehyde levels observed with AP. On the other hand, post-hemin administration did not show any protection against L-arginine-induced AP.

Conclusions. The current study indicates that the induction of HO-1 by hemin pre-treatment significantly ameliorated the L-arginine-induced pancreatitis and associated pulmonary complications may be due to its anti-inflammatory and antioxidant properties.

TLR4-mediated NF-κB signaling pathway mediates HMGB1-induced pancreatic injury in mice with severe acute pancreatitis

Severe acute pancreatitis (SAP) is an extremely dangerous acute abdominal disorder which causes multiple complications and has a high mortality rate. Previous research has suggested that high-mobility group box 1 (HMGB1) plays an important role in the pathogenesis of SAP; however, the mechanisms underlying this strong correlation remain unclear. In this study, to further investigate whether HMGB1 acts as a stimulating factor, and whether Toll-like receptor 4 (TLR4) acts as its major mediator in the development of pancreatic injury during SAP, recombinant human HMGB1 (rhHMGB1) and TLR4-deficient mice were used. We found that HMGB1 and TLR4 were highly expressed, and nuclear factor-κB (NF-κB) was activated in our mouse model of SAP. We noted that the rhHMGB1 pancreas-targeted injection activated the TLR4-mediated NF-κB signaling pathway and induced pancreatic injury in wild-type mice. In TLR4-deficient mice, the rhHMGB1-induced activation of NF-κB and pathological changes in the pancreas were less evident than in wild-type mice. Therefore, this study provides evidence that HMGB1 promotes the pathogenesis of pancreatitis, and its downstream TLR4-mediated NF-κB signaling pathway is a potential important mediator in the development of this form of pancreatic injury.

Correlation between serum levels of interleukin-6 and severity of acute pancreatitis

AIM: To assess the correlation between serum levels of interleukin (IL-6) and the severity of acute pancreatitis (AP).

METHODS: This study included 138 patients with severe AP (SAP), 126 with mild AP (MAP), and 150 healthy volunteers who underwent physical examination (control group). Serum levels of IL-6 in each group were detected and compared. The complications were recorded. The correlation between serum levels of IL-6 and Ranson score was analyzed, and the risk factors for the severity of AP were analyzed.

RESULTS: IL-6 level and Ranson score in the SAP group were both significantly higher than those in the MAP group and control group. IL-6 level and Ranson score in SAP patients with complications were significantly higher than those in SAP patients without complications (P < 0.05). Spearman correlation analysis showed that serum levels of IL-6 had a positive correlation with Ranson score. Using the severity of AP as the dependent variable, and age, gender, high Ranson score and high IL-6 level as the independent variables, we performed Logistic regression analysis and found that high IL-6 level was a risk factor for the severity of AP.

CONCLUSION: IL-6 is closely linked to the AP severity.

Recent advances in the investigation of pancreatic inflammation induced by large doses of basic amino acids in rodents

It has been known for approximately 30 years that large doses of the semi-essential basic amino acid L-arginine induce severe pancreatic inflammation in rats. Recently, it has been demonstrated that L-arginine can also induce pancreatitis in mice. Moreover, other basic amino acids like L-ornithine and L-lysine can cause exocrine pancreatic damage without affecting the endocrine parenchyma and the ducts in rats. The utilization of these noninvasive severe basic amino acid-induced pancreatitis models is becoming increasingly popular and appreciated as these models nicely reproduce most laboratory and morphological features of human pancreatitis. Consequently, the investigation of basic amino acid-induced pancreatitis may offer us a better understanding of the pathogenesis and possible treatment options of the human disease.

Specific lipase-responsive polymer-coated gadolinium nanoparticles for MR imaging of early acute pancreatitis

Currently, available methods for diagnosis of acute pancreatitis (AP) are mainly dependent on serum enzyme analysis and imaging techniques that are too low in sensitivity and specificity to accurately and promptly diagnose AP. The lack of early diagnostic tools highlights the need to search for a highly effective and specific diagnostic method. In this study, we synthesized a conditionally activated, gadolinium-containing, nanoparticle-based MRI nanoprobe as a diagnostic tool for the early identification of AP. Gadolinium diethylenetriaminepentaacetic fatty acid (Gd-DTPA-FA) nanoparticles were synthesized by conjugation of DTPA-FA ligand and gadolinium acetate. Gd-DTPA-FA exhibited low cytotoxicity and excellent biocompatibility when characterized in vitro and in vivo studies. L-arginine induced a gradual increase in the intensity of the T1-weighted MRI signal from 1 h to 36 h in AP rat models. The increase in signal intensity was most significant at 1 h, 6 h and 12 h. These results suggest that the Gd-DTPA-FA as an MRI contrast agent is highly efficient and specific to detect early AP.

PTD-NBD polypeptide down-regulates expression of NF-κB p65 in inflammatory pancreatic acinar cell injury in rats

AIM: To examine the effect of PTD-NBD polypeptide on the expression of nuclear factor κB (NF-κB) p65 in inflammatory pancreatic acinar cell injury in rats.

METHODS: Rat pancreatic acinar cells were isolated, cultured, and divided into a normal control group, an acute pancreatitis (AP) group and a PTD-NBD polypeptides group. An in vitro model of AP was induced by treating rat pancreatic acinar cells with lipopolysaccharide (10 mg/L). Cell morphological changes were observed, and the contents of amylase, superoxide dismutase (SOD) and IL-1β in culture medium were tested. Expression of NF-κB p65 mRNA and protein in cells was detected by RT-PCR and Western blot 6 and 12 h after modeling, respectively.

RESULTS: Compared to the control group, pancreatic acinar cell swelling and death were increased (6 h: 8.9 ± 0.34 vs 1.1 ± 0.13; 12 h: 9.4 ± 0.26 vs 1.2 ± 0.15, both P < 0.05), the contents of amylase (6 h: 2135.8 ± 347.2 vs 873.5 ± 91.6; 12 h: 3299.6 ± 217.7 vs 917.7 ± 101.9, both P < 0.05) and IL-1β (6 h: 84.9 ± 15.7 vs 39.3 ± 7.9; 12 h: 95.6 ± 17.1 vs 38.9 ± 5.2, both P < 0.05) were increased and the contents of SOD were decreased in culture medium (6 h: 116.3 ± 30.3 vs 176.2 ± 21.6; 12 h: 101.5 ± 25.6 vs 173.6 ± 27.9, P < 0.05), and the expression of NF-κB p65 in pancreatic acinar cells was increased (P < 0.05) in the AP group at 6 and 12 h after modeling. Compared to the AP group, pancreatic acinar cell swelling and death were lessened (6 h: 6.8 ± 0.23 vs 8.9 ± 0.34; 12 h: 7.5 ± 0.19 vs 9.4 ± 0.26, both P < 0.05), the contents of SOD were raised (6 h: 137.6 ± 27.4 vs 116.3 ± 30.3; 12 h: 144.3 ± 23.6 vs 101.5 ± 25.6, both P < 0.05) and the contents of amylase (6 h: 1951.5 ± 211.7 vs 2135.8 ± 347.2; 12 h: 1761.3 ± 231.5 vs 3299.6 ± 217.7, both P < 0.05) and IL-1β (6 h: 66.8 ± 11.6 vs 84.9 ± 15.7; 12 h: 54.8 ± 21.2 vs 95.6 ± 17.1, both P < 0.05) were decreased in culture medium, and the expression of NF-κB p65 mRNA and protein was down-regulated in the PAT-NBD polypeptide group (P < 0.05).

CONCLUSION: PTD-NBD polypeptide can inhibit LPS-induced activation of NF-κB p65, down-regulate IL-1β expression and up-regulate SOD content, thereby reducing inflammatory pancreatic acinar cell injury.