Adiponectin deficiency enhanced the severity of cerulein-induced chronic pancreatitis in mice

High-mobility group box 1 fragment ameliorates chronic pancreatitis induced by caerulein in mice

BACKGROUND

Chronic pancreatitis (CP) is a progressive disease characterized by pancreatic fibrosis for which effective treatment options are lacking. Mesenchymal stem cells (MSCs) have shown potential for fibrosis treatment but face limitations in clinical application. The high-mobility group box 1 (HMGB1) fragment mobilizes MSCs from bone marrow into the blood and has emerged as a promising therapeutic agent for tissue regeneration in various pathological conditions. The aim of this study was to investigate the potential therapeutic effects of systemic administration of the HMGB1 fragment in a mouse model of CP.

METHODS

A caerulein-induced CP mouse model was used, and the HMGB1 fragment was administered by tail vein injection. Parameters such as body weight, pancreatic tissue damage, fibrosis, inflammatory cytokine expression, and collagen-related gene expression were evaluated using various assays, including immunohistochemistry, real-time PCR, serum analysis, and single-cell transcriptome analysis. And the migration of MSCs to the pancreas was evaluated using the parabiosis model.

RESULTS

Administration of the HMGB1 fragment was associated with significant improvements in pancreatic tissue damage and fibrosis. It suppressed the expression of inflammatory cytokines and activated platelet-derived growth factor receptor-α+ MSCs, leading to their accumulation in the pancreas. The HMGB1 fragment also shifted gene expression patterns associated with pancreatic fibrosis toward those of the normal pancreas. Systemic administration of the HMGB1 fragment demonstrated therapeutic efficacy in attenuating pancreatic tissue damage and fibrosis in a CP mouse model.

CONCLUSION

These findings highlight the potential of the HMGB1 fragment as a therapeutic target for the treatment of CP.

Circulating Biomarkers Involved in the Development of and Progression to Chronic Pancreatitis-A Literature Review

Chronic pancreatitis (CP) is the end-stage of continuous inflammation and fibrosis in the pancreas evolving from acute- to recurrent acute-, early, and, finally, end-stage CP. Currently, prevention is the only way to reduce disease burden. In this setting, early detection is of great importance. Due to the anatomy and risks associated with direct sampling from pancreatic tissue, most of our information on the human pancreas arises from circulating biomarkers thought to be involved in pancreatic pathophysiology or injury. The present review provides the status of circulating biomarkers involved in the development of and progression to CP.

Pancreatitis initiated pancreatic ductal adenocarcinoma: Pathophysiology explaining clinical evidence

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant lethal disease due to its asymptomatic at its early lesion of the disease and drug resistance. Target therapy associated with molecular pathways so far seems not to produce reasonable outcomes. Understanding of the molecular mechanisms underlying inflammation-initiated tumorigenesis may be helpful for development of an effective therapy of the disease. A line of studies showed that pancreatic tumorigenesis was resulted from pancreatitis, which was caused synergistically by various pancreatic cells. This review focuses on those players and their possible clinic implications, such as exocrine acinar cells, ductal cells, and various stromal cells, including pancreatic stellate cells (PSCs), macrophages, lymphocytes, neutrophils, mast cells, adipocytes and endothelial cells, working together with each other in an inflammation-mediated microenvironment governed by a myriad of cellular signaling networks towards PDAC.

Mechanism of Transplanted Islet Engraftment in Visceral White Adipose Tissue

BACKGROUND

White adipose tissue (WAT) is a candidate transplantation site for islets. However, the mechanism of islet engraftment in WAT has not been fully investigated. In this study, we attempted to clarify the therapeutic effect and mechanism of islet transplantation into visceral WAT.

METHODS

Two hundred mouse islets were transplanted into epididymal WAT of syngeneic diabetic mice by wrapping islets with the tissue (fat-covered group). Mice that received intraperitoneal and renal subcapsular islet transplantations were used as negative and positive control groups, respectively.

RESULTS

The transplant efficacy, including improvements in blood glucose and plasma insulin levels and in glucose tolerance tests, of the fat-covered group was superior to the negative control group and almost equal to the positive control group. Vessel density of engrafted islets in the fat-covered group was higher than that in the positive control group. It was speculated that the mechanism of islet engraftment in WAT might consist of trapping islets in WAT, adhesion of islets via a combination of adhesion factors (fibronectin and integrin β1), and promotion of angiogenesis in islets by expression of angiogenic factors induced by adiponectin.

CONCLUSIONS

Visceral WAT is an important candidate for islet transplantation. Adhesion factors and adiponectin might contribute to islet engraftment into WAT. Further studies to elucidate the detailed mechanism are necessary.

Significant of adiponectin in gastropathy: Case-controlled study

Background

Gastropathy is a medical broad term applied for stomach diseases that affect mucosal lining characterized by epithelial injury. There are many types of gastropathy ranging from harmless conditions to more serious ones like cancer.

Aim of the study

to assess the significant effect of adiponectin and its level in patients with gastropathy.

Patients and methods

This case-control study includes 35 patients with gastropathy confirmed by gastroscope and thirty control group. Anthropometric Measurements like Weight, height, waist circumference, body mass index, and waist circumference. Blood sample was collected from the patients and control group and serum tested for lipid profile that includes (cholesterol, triglyceride, HDLP, LDLP) (Human-Germany), and adiponectin (Shanghai Biologic Technology-China) using Enzyme-Linked Immunosorbent Assay (ELISA).

Results

There is a significant difference between the two groups regarding height, weight, waist circumference, and waist to hip ratio (P-value 0.002,0.009, 0.002 and 0.015 respectively). Regarding adiponectin, there is no significant difference between patients (9.54 ± 5.821 and control 9.119 ± 7.062)(P = 0.796). Lipid profile showed a significant increase in cholesterol (p = 0.0001) and triglyceride (0.007) in patients group while there is no significant difference in HDL, LDL and LDL/HDL ratio.

Conclusions

Adiponectin had no role in the development of gastropathy. Patients with gastropathy had a significant increase in the serum level of cholesterol and triglyceride. There is a significant negative correlation between adiponectin and weight, body mass index, waist circumference, triglyceride, and low-density lipoprotein.

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Gastropathy is a medical broad term applied for stomach diseases.

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Effect of adiponectin and its level in patients with gastropathy.

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This case-control study includes 35 patients with gastropathy confirmed by gastroscope and thirty control group.

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Anthropometric Measurements and blood sample were collected from two groups.

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There is a significant difference between two groups regarding height, weight, waist circumference and waist to hip ratio while adiponectin there is no significant difference between two groups.

Cerulein-induced chronic pancreatitis in Swiss albino mice: An improved short-term model for pharmacological screening

There is a need for short-term, reliable and reproducible animal model of chronic pancreatitis (CP) in small animals like mice. This study was aimed to establish the 9 exposures of cerulein-induced CP in mice. Repeated intraperitoneal cerulein injections were performed at 6 consecutive doses (50 μg/kg)/day, 3 days a week for 3 weeks to induce chronic pancreatitis in Swiss albino mice. The severity of damage was assessed by biochemical assays and histopathology. The expression of pro-inflammatory cytokine and fibrotic proteins was assessed by IHC and western blotting. The cerulein treated mice showed significantly elevated plasma amylase (p < .0285) and lipase levels (p < .0022) and resulted in significantly increased pancreatic oxidative (p < .0022) and nitrosative (p < .0022) stress. The hydroxyproline levels were 3.06 fold increased in the cerulein treated mice. The expressions of fibrotic cytokine TGF-β1 by 1.8 folds and pro-inflammatory cytokines TNF-α by 2.3 fold, IL-6 by 2.2 fold and IL-1β by 3.7 fold were markedly increased in cerulein treated mice. The histological evaluations indicated increased inflammatory cells infiltration and deposition of collagen. Moreover, the expression of fibrotic markers such as α-SMA increased by 2.5 folds (p < .00014), collagen1a by 1.3 folds (p < .0258) and fibronectin by 3.5 folds (p < .00014) were significantly increased. Our study demonstrates the superiority of 9 exposures of cerulein-induced CP model in mice with the reduction of duration, cerulein exposure, more economical and mortality rate of mice over the available models. Therefore, our model may be suitable to evaluate the pharmacological effects of new drugs in chronic pancreatitis.

Inhibition of Jak/STAT signaling reduces the activation of pancreatic stellate cells in vitro and limits caerulein-induced chronic pancreatitis in vivo

Chronic pancreatitis (CP) is a fibro-inflammatory disease leading to pain, maldigestion, and pancreatic insufficiency. No therapeutic options exist due to a limited understanding of the biology of CP pathology. Recent findings implicate pancreatic stellate cells (PSC) as prominent mediators of inflammatory and fibrotic processes during CP. Here, we utilized primary and immortalized PSC obtained from mice and patients with CP or pancreatic cancer to examine the effect of Jak/STAT and MAPK pathway inhibition in vitro. The well-characterized caerulein model of CP was used to assess the therapeutic efficacy of Jak1/2 inhibition in vivo. Treatment of cultured PSC with the Jak1/2 inhibitor ruxolitinib reduced STAT3 phosphorylation, cell proliferation, and expression of alpha-smooth muscle actin (α-SMA), a marker of PSC activation. Treatment with the MAPK inhibitor, MEK162, had less consistent effects on PSC proliferation and no impact on activation. In the caerulein-induced murine model of CP, administration of ruxolitinib for one week significantly reduced biomarkers of inflammation and fibrosis. These data suggest that the Jak/STAT pathway plays a prominent role in PSC proliferation and activation. In vivo treatment with the Jak1/2 inhibitor ruxolitinib reduced the severity of experimental CP, suggesting that targeting Jak/STAT signaling may represent a promising therapeutic strategy for CP.

Adiponectin as a routine clinical biomarker

Adiponectin is a protein synthesized and secreted predominantly by adipocytes into the peripheral blood. However, circulating adiponectin level is inversely related with body weight, especially visceral fat accumulation. The mechanism of this paradoxical relation remains obscure. Low circulating adiponectin concentrations (hypoadiponectinemia; <4 μg/mL) are associated with a variety of diseases, including dysmetabolism (type 2 diabetes, insulin resistance, hypertension, dyslipidemia, metabolic syndrome, hyperuricemia), atherosclerosis (coronary artery disease, stroke, peripheral artery disease), sleep apnea, non-alcoholic fatty liver disease, gastritis and gastro-esophageal reflux disease, inflammatory bowel diseases, pancreatitis, osteoporosis, and cancer (endometrial cancer, postmenopausal breast cancer, leukemia, colon cancer, gastric cancer, prostate cancer). On the other hand, hyperadiponectinemia is associated with cardiac, renal and pulmonary diseases. This review article focuses on the significance of adiponectin as a clinical biomarker of obesity-related diseases. Routine measurement of adiponectin in patients with lifestyle-related diseases is highly recommended.

Adiponectin in inflammatory and immune-mediated diseases

Circulating levels of adiponectin (APN) are reduced in obesity and associated comorbidities, with inflammation playing an important role in downregulating APN production. In contrast to obesity and metabolic disease, elevated systemic and local levels of APN are present in patients with inflammatory and immune-mediated diseases, including autoimmune and pulmonary conditions, heart and kidney failure, viral hepatitis, organ transplantation and perhaps critical illness. A positive association between inflammation and APN is usually reported in inflammatory/immune pathologies, in contrast with the negative correlation typical of metabolic disease. This review discusses the role of APN in modulation of inflammation and immunity and the potential mechanisms leading to increased levels of APN in inflammatory/immune diseases, including modification of adipose tissue physiology; relative contribution of different tissues and adipose depots; hormonal, pharmacological, nutritional and life style factors; the potential contribution of the microbiota as well as the role of altered APN clearance and release from T-cadherin-associated tissue reservoirs. Potential reasons for some of the apparently contradictory findings on the role of APN as a modulator of immunity and inflammation are also discussed, including a comparison of types of recombinant APN used for in vitro studies and strain-dependent differences in the phenotype of APN KO mice.

Adipokine levels in the course of mild biliary pancreatitis

OBJECTIVES

Obesity markedly increases the risk of severe acute pancreatitis (AP). Several adipokines have been ascribed a role as a predictor of clinical severity in AP. Therefore, the aim of this study was to investigate a possible relationship between leptin and adiponectin and mild biliary AP.

METHODS

We included 24 consecutive patients with mild biliary AP and 24 consecutive healthy age- and sex-matched controls. Clinical severity was classified by the Ranson score. ELISA was used to assess leptin and adiponectin levels on admission and in remission. Complete blood cell counts and other laboratory tests were also performed at baseline and in remission.

RESULTS

Leptin, adiponectin, insulin and HOMA-IR measurements showed no difference in pancreatitis patients both on admission and in remission compared to the control group. No difference was found in leptin, insulin or HOMA-IR levels in the course of pancreatitis. However, adiponectin levels were higher in remission compared to admission.

CONCLUSIONS

Increased adiponectin levels in remission may be an indication of improvement in this condition. Further studies are needed to determine whether adiponectin provides protection from AP.

Serum levels of adipocyte fatty acid-binding protein are decreased in chronic pancreatitis

OBJECTIVE

Chronic pancreatitis (CP) is associated with an increased risk for diabetes mellitus and vascular disease. Adipocyte fatty acid-binding protein (AFABP) is a novel adipokine that is independently associated with the metabolic syndrome and cardiovascular disease. In the current study, we investigated serum AFABP levels in CP patients compared with sex- and body mass index-matched controls.

METHODS

Adipocyte fatty acid-binding protein was determined with enzyme-linked immunosorbent assay in control subjects (n = 60) and diabetic as well as nondiabetic CP (n = 60) patients and correlated to clinical and biochemical measures of glucose and lipid metabolism, as well as renal function in both groups.

RESULTS

Median serum AFABP levels were significantly lower in CP patients compared with controls (12.5 vs 20.9 μg/L, P = 0.003). Furthermore, body mass index, sex, and CP independently predicted circulating AFABP. In contrast, no significant difference in circulating AFABP could be demonstrated between diabetic and nondiabetic CP patients.

CONCLUSIONS

Circulating AFABP is paradoxically lower in CP patients and does not depend on pancreatic diabetes. Our data do not support a role of circulating AFABP in metabolic and vascular risk in CP patients.

Protective role of adiponectin against ethanol-induced gastric injury in mice

Adiponectin is an anti-inflammatory molecule released from adipocytes, and serum adiponectin concentrations are reduced in obesity. We previously reported that gastric erosion occurs in association with obesity and low serum adiponectin levels. In the present study, we examined adiponectin-knockout (APN-KO) mice to elucidate the role of adiponectin in gastric mucosal injury. Gastric injury was induced by oral administration of ethanol in wild-type (WT) and APN-KO mice. Ethanol treatment induced severe gastric injury in APN-KO mice compared with WT mice. In APN-KO mice, increased apoptotic cells and decreased expression of prostaglandin E(2) (PGE(2)) were detected in the injured stomach. We next assessed the effect of adiponectin on the cellular response to ethanol treatment and wound repair in rat gastric mucosal cells (RGM1). Adiponectin induced the expression of PGE(2) and cyclooxygenase 2 (COX-2) in ethanol-treated RGM1 cells. RGM1 cells exhibited efficient wound repair accompanied by increased PGE(2) expression in the presence of adiponectin. Coadministration of adiponectin with celecoxib, a COX-2 inhibitor, inhibited efficient wound repair. These findings indicate that adiponectin has a protective role against ethanol-induced gastric mucosal injury in mice. This effect may be partially mediated by the efficient wound repair of epithelial cells via increased PGE(2) expression.

Role of IL-6 in the resolution of pancreatitis in obese mice

Obesity increases severity of acute pancreatitis and risk of pancreatic cancer. Pancreatitis and obesity are associated with elevated IL-6, a cytokine involved in inflammation and tumorigenesis. We studied the role of IL-6 in the response of lean and obese mice to pancreatitis induced by IL-12 + IL-18. Lean and diet-induced obese (DIO) WT and IL-6 KO mice and ob/ob mice pretreated with anti-IL-6 antibodies were evaluated at Days 1, 7, and 15 after induction of pancreatitis. Prolonged elevation of IL-6 in serum and visceral adipose tissue was observed in DIO versus lean WT mice, whereas circulating sIL-6R declined in DIO but not lean mice with pancreatitis. The severe inflammation and lethality of DIO mice were also observed in IL-6 KO mice. However, the delayed resolution of neutrophil infiltration; sustained production of CXCL1, CXCL2, and CCL2; prolonged activation of STAT-3; and induction of MMP-7 in the pancreas, as well as heightened induction of serum amylase A of DIO mice, were blunted significantly in DIO IL-6 KO mice. In DIO mice, production of OPN and TIMP-1 was increased for a prolonged period, and this was mediated by IL-6 in the liver but not the pancreas. Results obtained in IL-6 KO mice were confirmed in ob/ob mice pretreated with anti-IL-6 antibodies. In conclusion, IL-6 does not contribute to the increased severity of pancreatitis of obese mice but participates in delayed recovery from acute inflammation and may favor development of a protumorigenic environment through prolonged activation of STAT-3, induction of MMP-7, and sustained production of chemokines.

Association of low serum adiponectin levels with erosive esophagitis in men: an analysis of 2405 subjects undergoing physical check-ups

BACKGROUND

Obesity is a risk factor for gastro-esophageal reflux disease (GERD). It is generally considered that intra-abdominal pressure in obese subjects is involved in the pathogenesis of GERD through acid exposure to the esophagus. Recently, visceral fat has been recognized as an endocrine organ that secretes various adipocytokines including adiponectin. The aim of this study was to elucidate the relation between adiponectin and erosive esophagitis.

METHODS

This was a cross-sectional retrospective observational study: 2405 consecutive subjects who underwent screening esophago-gastro-duodenoscopy with serum adiponectin measurement as part of their physical check-up programs were analyzed. Clinical factors were compared between subjects with and without erosive esophagitis. The association between adiponectin and erosive esophagitis was assessed using a bootstrapping re-sampling method after adjustment for factors that tended to be different in univariate analysis.

RESULTS

Serum adiponectin levels were significantly lower in those with erosive esophagitis (8.17 μg/ml) than in those without (10.1). The erosive esophagitis group had a greater body mass index (BMI) and waist circumference (WC) and a higher prevalence of hiatal hernia. Using the bootstrap method, with a lower adiponectin cut-off value of 3-7 μg/ml, the lower limit of the 95% confidence interval of the adjusted odds ratio consistently exceeded 1 after adjustment for BMI and hiatal hernia in men. When adjusting for WC instead of BMI, the effect of adiponectin was reduced but remained significant at a lower cut-off value (3-3.5 μg/ml).

CONCLUSIONS

Low serum adiponectin levels may be associated with an increased risk for erosive esophagitis in men.

Lower serum level of adiponectin is associated with increased risk of endoscopic erosive gastritis

BACKGROUND

Obesity is recently known as a risk factor for endoscopic gastritis. Adiponectin is an anti-inflammatory cytokine secreted from fat tissue, and its serum concentrations are reduced in obesity. The relation between adiponectin and gastritis remains unclear.

AIMS

The aim of this study was to determine whether lower serum adiponectin level is associated with the risk of endoscopic gastritis.

METHODS

We analyzed medical records of participants of a routine health check-up examination. Association among endoscopic findings, serum adiponectin level, and other clinical factors including age, sex, alcohol habit, smoking habit, body mass index (BMI), blood pressure, cholesterol, triglyceride, glucose, and insulin were investigated. Endoscopic erosive gastritis was defined as a flat or minimally depressed white spot surrounded by a reddish area or small elevation with central umbilications mimicking octopus' suckers.

RESULTS

A total of 2,400 participants were enrolled. BMI was significantly higher in gastritis-positive participants than in gastritis-negative participants. Serum adiponectin levels were significantly lower in gastritis-positive participants than in gastritis-negative participants. Multivariate logistic regression analysis revealed that lower serum adiponectin level (OR 0.96; 95% CI 0.93-0.99), smoking (OR 0.50; 95% CI 0.30-0.80), higher blood pressure (OR 1.02; 95% CI 1.01-1.03), and duodenitis (OR 1.8; 95% CI 1.00-3.09) were significantly associated with endoscopic erosive gastritis.

CONCLUSIONS

Lower serum level of adiponectin may increase the risk of endoscopic erosive gastritis, independently of BMI. Our findings facilitate further study to clarify the role of hypoadiponectinemia in erosive gastritis.