Small molecule SWELL1 complex induction improves glycemic control and nonalcoholic fatty liver disease in murine Type 2 diabetes.

Type 2 diabetes is associated with insulin resistance, impaired pancreatic ß-cell insulin secretion, and nonalcoholic fatty liver disease. Tissue-specific SWELL1 ablation impairs insulin signaling in adipose, skeletal muscle, and endothelium, and impairs ß-cell insulin secretion and glycemic control. Here, we show that ICl,SWELL and SWELL1 protein are reduced in adipose and ß-cells in murine and human diabetes. Combining cryo-electron microscopy, molecular docking, medicinal chemistry, and functional studies, we define a structure activity relationship to rationally-design active derivatives of a SWELL1 channel inhibitor (DCPIB/SN-401), that bind the SWELL1 hexameric complex, restore SWELL1 protein, plasma membrane trafficking, signaling, glycemic control and islet insulin secretion via SWELL1-dependent mechanisms. In vivo, SN-401 restores glycemic control, reduces hepatic steatosis/injury, improves insulin-sensitivity and insulin secretion in murine diabetes. These findings demonstrate that SWELL1 channel modulators improve SWELL1-dependent systemic metabolism in Type 2 diabetes, representing a first-in-class therapeutic approach for diabetes and nonalcoholic fatty liver disease.

Dominant negative p38 mitogen-activated protein kinase expression inhibits NF-kappaB activation in AR42J cells.

BACKGROUND: The role of the p38 mitogen-activated protein (MAP) kinase in acute pancreatitis pathogenesis is controversial. We hypothesize that p38 plays a role in regulating NF-kappaB activation in exocrine pancreatic cells. METHODS: AR42J cells incorporating an NF-kappaB-responsive luciferase reporter, with and without adenoviral transduction of DNp38, were stimulated with cholecystokinin (CCK) or tumor necrosis factor-alpha (TNF-alpha) prior to measuring NF-kappaB activation. RESULTS: CCK- or TNF-alpha-stimulated NF-kappaB-dependent gene transcription (luciferase assay) was substantially subdued by DNp38 expression. These findings were confirmed by electrophoretic mobility shift assay. Nuclear translocation of the p65 NF-kappaB subunit following agonist stimulation was evident (supershift). Characterization studies showed excellent adenoviral infection efficiency and cell viability in our AR42J cell model. Agonist-stimulated dose- and time-dependent p38 activation, with inhibition by DNp38 expression, was also confirmed. CONCLUSION: The p38 MAP kinase regulates NF-kappaB pathway activation in exocrine pancreatic cells, and thus potentially plays a role in the mechanism of acute pancreatitis pathogenesis..

A novel model of severe gallstone pancreatitis: murine pancreatic duct ligation results in systemic inflammation and substantial mortality.

BACKGROUND: Suitable experimental models of gallstone pancreatitis with systemic inflammation and mortality are limited. We developed a novel murine model of duct-ligation-induced acute pancreatitis associated with multiorgan dysfunction and severe mortality. METHODS: Laparotomy was done on C57/BL6 mice followed by pancreatic duct (PD) ligation, bile duct (BD) ligation without PD ligation, or sham operation. RESULTS: Only mice with PD ligation developed acute pancreatitis and had 100% mortality. Pulmonary compliance was significantly reduced after PD ligation but not BD ligation. Bronchoalveolar lavage fluid neutrophil count and interleukin-1ß concentration, and the plasma creatinine level, were significantly elevated with PD ligation but not BD ligation. Pancreatic nuclear factor κB (p65) and activator protein 1 (c-Jun) were activated within 1 h of PD ligation. CONCLUSION: PD-ligation-induced acute pancreatitis in mice is associated with systemic inflammation, acute lung injury, multiorgan dysfunction and death. The development of this novel model is an exciting and notable advance in the field.

Association of gallbladder hyperkinesia with acalculous chronic cholecystitis: A case-control study.

BACKGROUND: This is the first case-control study investigating an association between gallbladder hyperkinesia and symptomatic acalculous chronic cholecystitis. METHODS: This retrospective study in a single academic center compared resolution of biliary pain in adults with gallbladder hyperkinesia, defined as a hepatobiliary iminodiacetic acid scan ejection fraction ≥80%, undergoing cholecystectomy (study group) with those treated medically without cholecystectomy (control group). Of 1,477 hepatobiliary iminodiacetic acid scans done between 2013 and 2018, a total of 296 adults without gallstones had an ejection fraction ≥80%, of whom 46 patients met predetermined eligibility criteria. Demographic data, hepatobiliary iminodiacetic acid scan ejection fraction, chronicity of pain, and resolution of pain were compared between groups. RESULTS: Demographics (mean ± standard deviation) in the control group (n = 25) and in the study group (n = 21) were, respectively, age 40 y ± 16 y and 39 y ± 14 y, body mass index 28.9 ± 5.2 and 29.1 ± 7.1 kg/m2, with 15 (60%) and 18 (86%) females in each. Resolution of pain after cholecystectomy occurred in 18 of 21 patients (86%); however, pain persisted in 20 of 25 patients (80%) treated medically after mean follow-up of 36 ± 28 months (range 10-120 months) (P < .01). Pain resolution with cholecystectomy was independent of demographic variables, hepatobiliary iminodiacetic acid scan ejection fraction, and chronicity of pain. The odds of pain resolution was 19.7 times greater with cholecystectomy than without (odds ratio, 19.7; 95% confidence interval, 4.34, 89.43; P < .01), and remained robust even with the odds adjusted for each covariate. Gallbladder histopathology confirmed chronic cholecystitis in all 21 cholecystectomy specimens. CONCLUSION: Symptomatic gallbladder hyperkinesia could be a new indication for cholecystectomy in adults.

Dataset on the performance of a three phase induction motor under balanced and unbalanced supply voltage conditions.

Three phase induction motors (TPIM) are extensively used for various applications in the industry for driving cranes, hoists, lifts, rolling mills, cooling fans, textile operations, and so forth. TPIM are designed to operate on balanced three phase power supply, but sometimes three phase supply line voltages to which the TPIM is connected may be unbalanced. In this data article, the operational data of a TPIM operating under changing voltage scenarios is profiled to determine the variations in the magnitude of the operational parameters of the motor. The magnitude of each of the line voltages was separately varied from the balanced state (0% unbalance) until 5% voltage unbalance condition was achieved, in line with the recommendations and guidelines of the National Electrical Manufactures Association. The motor parameters; both mechanical and electrical, at various slip values were collected in six sets for the 0%, 1%, 2%, 3%, 4%, and 5% unbalance voltage conditions. Frequency distributions and statistical analysis were carried out to identify the data pattern and data variation trends among the parameters in the dataset.

Enteral exclusion increases MAP kinase activation and cytokine production in a model of gallstone pancreatitis.

BACKGROUND: We have previously demonstrated that enteral exclusion augments pancreatic p38 mitogen-activated protein (MAP) kinase activation and tumor necrosis factor-alpha (TNF-alpha) production after bile-pancreatic duct ligation in rats. METHODS: In the present study, we evaluated c-Jun NH(2)-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) activation, and cytokine production, in pancreata of duct-ligated rats with and without duodenal bile-pancreatic juice replacement from a donor rat. We hypothesized that enteral exclusion of bile-pancreatic juice activates stress kinases and induces cytokine production in ligation-induced acute pancreatitis. RESULTS: Increased JNK and ERK activation after ligation are inhibited by bile-pancreatic juice replacement. Increases in pancreatic production of IL-1beta and IL-12 after ligation are significantly subdued by replacement. In additional in vitro studies, we show that cholecystokinin- or TNF-alpha-stimulated nuclear transcription factor kappa-B activation in AR42J cells is inhibited by dominant negative ERK2. CONCLUSIONS: Our novel findings using our Donor Rat Model indicate that bile-pancreatic juice exclusion induces MAP kinase activation and exacerbates cell stress and inflammation in this experimental model of gallstone pancreatitis. and IAP.

Causes of 30-day bariatric surgery mortality: with emphasis on bypass obstruction.

BACKGROUND: This is a study of the causes of 30-day postoperative death following surgical treatment for obesity and a search for ways to decrease an already low mortality rate. METHODS: Data were contributed from 1986-2004 to the International Bariatric Surgery Registry by 85 sites, representing 137 surgeons. A spread-sheet was prepared with rows for causes and columns for patients. The 251 causes contributing to 93 deaths were then marked in cells wherever a patient was noted to have one of the causes. Rows and columns were then moved into positions that provided patterns of best fit. RESULTS: 11 patterns were found. 10 had well known initiating causes of death. Overall operative 30-day mortality was 0.24% (93 / 38,501). The most common cause of death was pulmonary embolism (32%, 30/93). 14 deaths were caused by leaks (15%, 14/93), and were equally prevalent after simple (15%, 2/14) or complex (15%, 12/79) operations. Small bowel obstruction caused 8 deaths, exclusively after complex operations. 5 of these involved the bypassed biliopancreatic limb and were defined as "bypass obstruction". CONCLUSIONS: A spread-sheet study of cause of 30-day postoperative death revealed a rapidly lethal initiating complication of Roux-en-Y gastric bypass obstruction that requires the earliest possible recognition and treatment. Bypass obstruction needs a name and code to facilitate recognition, study, prevention and early treatment. Spread-sheet pattern analysis of all available data helped identify the initiating cause of death for individual patients when multiple data elements were present.

Comparison of size of proximal gastric pouch and short-term weight loss following routine upper gastrointestinal contrast study after laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: The authors investigated whether there is any correlation between gastric pouch size measured by routine upper gastrointestinal contrast study (UGI) after laparoscopic Roux-en-Y gastric bypass (LRYGBP) and short-term weight loss. METHODS: The study group consisted of 82 patients (66F, 16M) who underwent LRYGBP. Body mass index before surgery ranged from 35.4 to 71.7 kg/m2, with a mean of 47.4 kg/m2. UGI was performed 1 day after LRYGBP in all patients. Proximal gastric pouch size was estimated by multiplying maximal transverse and longitudinal diameters on AP spot image or film. Percent excess weight loss (%EWL) obtained at 3, 6, 12 and 24 months after surgery was used as an indicator of short-term results. According to the presence of contrast passage through the gastrojejunostomy, each patient was classified into 2 groups: Group A, negative; Group B, positive. RESULTS: There was no correlation between proximal gastric pouch size and %EWL at any point of time (P>0.05). The correlation coefficients calculated for 3, 6, 12 and 24 months after surgery were 0.038, 0.110, 0.015 and 0.042, respectively (Pearson correlation test). The gastric pouch size of Group A was larger than that of Group B (Student t-test, P<0.001). There was no difference in %EWL between Groups A and B at 3 and 6 months after surgery (P>0.05). CONCLUSION: Pouch size area, measured by routine UGI study on the first postoperative day, does not influence short-term postoperative weight loss.

Isolation and Patch-Clamp of Primary Adipocytes.

The patch-clamp technique allows for the study of ion channel activity in the native adipocyte environment to better understand the contributions of ion channels to adipocyte signaling. Here, we describe methods for isolating primary mature adipocytes from both mouse and human white adipose tissues (subcutaneous and visceral). From the same preparation, we describe how to culture and differentiate preadipocytes isolated from the stromal vascular fraction. We then describe in detail patch-clamp methods, including both whole-cell and perforated-patch configurations.

SWELL1 is a regulator of adipocyte size, insulin signalling and glucose homeostasis.

Adipocytes undergo considerable volumetric expansion in the setting of obesity. It has been proposed that such marked increases in adipocyte size may be sensed via adipocyte-autonomous mechanisms to mediate size-dependent intracellular signalling. Here, we show that SWELL1 (LRRC8a), a member of the Leucine-Rich Repeat Containing protein family, is an essential component of a volume-sensitive ion channel (VRAC) in adipocytes. We find that SWELL1-mediated VRAC is augmented in hypertrophic murine and human adipocytes in the setting of obesity. SWELL1 regulates adipocyte insulin-PI3K-AKT2-GLUT4 signalling, glucose uptake and lipid content via SWELL1 C-terminal leucine-rich repeat domain interactions with GRB2/Cav1. Silencing GRB2 in SWELL1 KO adipocytes rescues insulin-pAKT2 signalling. In vivo, shRNA-mediated SWELL1 knockdown and adipose-targeted SWELL1 knockout reduce adiposity and adipocyte size in obese mice while impairing systemic glycaemia and insulin sensitivity. These studies identify SWELL1 as a cell-autonomous sensor of adipocyte size that regulates adipocyte growth, insulin sensitivity and glucose tolerance.

Erratum: SWELL1 is a regulator of adipocyte size, insulin signalling and glucose homeostasis.

This corrects the article DOI: 10.1038/ncb3514.

In vitro evidence for role of ERK, p38, and JNK in exocrine pancreatic cytokine production.

Elucidation of mechanisms of acinar cell cytokine production is essential for a better understanding of acute pancreatitis pathogenesis. We hypothesize that the stress kinases ERK, p38, and JNK play an important role in acinar cell cytokine production. Rat pancreatic fragments were incubated with 100 nM concentration of the cholecystokinin analog caerulein or 100 nM caerulein and specific ERK inhibitor (100 microM PD98059), specific p38 inhibitor (10 microM SB203580), or specific JNK inhibitor (20 microM SP600125). After 3 hours of caerulein treatment, pancreatic fragments were homogenized and assayed for total and phosphorylated ERK, p38, and JNK, and for tumor necrosis factor-alpha or interleukin-1beta concentrations (ELISA). Pancreatic fragments stimulated with caerulein showed activation of ERK, p38, and JNK and increased cytokine concentrations (ANOVA, P<0.05). Specific stress kinase inhibitors significantly attenuated caerulein-induced activation of the corresponding stress kinase and cytokine production; however, the effect of the JNK inhibitor was comparatively less convincing. Increased activation of ERK, p38, and JNK in pancreatic fragments was not associated with significant increases in total ERK, total p38, or total JNK concentrations. The stress kinases ERK and p38 play an important role in caerulein-stimulated exocrine pancreatic overproduction of cytokines. The role of JNK needs further evaluation in this experimental model.

Bile-pancreatic juice exclusion promotes Akt/NF-kappaB activation and chemokine production in ligation-induced acute pancreatitis.

Using a unique surgical model (the donor rat model), we showed previously that duodenal replacement of bile-pancreatic juice, obtained fresh from a donor rat, ameliorates ligation-induced acute pancreatitis. We hypothesize that bile-pancreatic juice exclusion from gut exacerbates Akt/nuclear factor-kappaB (NF-kappaB) pathway activation and induces chemokine production in ligation-induced acute pancreatitis. We compared rats with bile-pancreatic duct ligation to those with duodenal bile-pancreatic juice replacement fresh from a donor rat beginning immediately before duct ligation. Sham control rats had ducts dissected but not ligated. Rats were killed 1 or 3 hours after operation (n = 7/group). Akt activation (immunoblotting, immune-complex kinase assay, and ELISA), inhibitory protein I-kappaB (IkappaB) activation (immunoblotting), and production of chemokines MCP-1 and RANTES (ELISA) were measured in pancreatic homogenates. NF-kappaB was quantitated in nuclear fractions using electrophoretic mobility shift assay. Duct ligation produced significant increases in pancreatic Akt, IkappaB, and NF-kappaB activation and production of MCP-1 and RANTES. Activation of the Akt/NF-kappaB pathway and increased MCP-1 and RANTES production in response to duct ligation were significantly reduced by bile-pancreatic juice replacement (ANOVA, P < 0.05). Bile-pancreatic juice exclusion stimulates Akt/NF-kappaB pathway activation and increases chemokine production in ligation-induced acute pancreatitis.

Effects of gastric bypass procedures on bone mineral density, calcium, parathyroid hormone, and vitamin D.

Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by 9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n = 14; P < .001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year, by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS) by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS) and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively (25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the first year.

Exacerbation of acute pancreatitis by combined cholinergic stimulation and duct obstruction.

BACKGROUND: The role of cholinergic pathways in the pathogenesis of bile-pancreatic duct ligation (BPDL)-induced acute pancreatitis in rats remains controversial. We hypothesized that cholinergic stimulation exacerbates acute pancreatic inflammation in the presence of duct obstruction. METHODS: We studied 34 rats divided into 5 groups as follows: (1) sham operation; (2) BPDL; (3) BPDL with duodenal bile-pancreatic juice (BPJ) replacement fresh from a donor rat; (4) BPDL with BPJ replacement as in 3 above, and carbachol (CCh) 5 ug/h subcutaneously; or (5) CCh 5 ug/h subcutaneously only. Rats were killed after 6 hours. RESULTS: The P value was less than .05 by analysis of variance. Pancreatic morphologic changes and zymogen fraction hyperamylasemia seen with duct ligation (2 vs. 1) were ameliorated significantly by duodenal BPJ replacement (3 vs. 2), but not when exogenous CCh was administered (4 vs. 3), whereas CCh alone showed no significant changes compared with sham (5 vs. 1). CONCLUSIONS: Cholinergic stimulation and duct obstruction synergistically amplify acinar hyperstimulation and exacerbate acute pancreatitis.

Scheduled intravenous acetaminophen reduces postoperative narcotic analgesic demand and requirement after laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Intravenous (i.v.) acetaminophen has the potential to reduce postoperative narcotic analgesic requirement but this has not been reported in bariatric surgery. As lower dosages could reduce undesirable narcotic side effects, we investigated the opioid-sparing effect of concomitant i.v. acetaminophen in bariatric surgery. METHODS: We performed a retrospective review of our electronic medical records of laparoscopic Roux-en-Y gastric bypasses (LRYGB) performed for severe obesity between 2011 and 2013. We identified 183 patients that received scheduled i.v. acetaminophen in addition to morphine sulfate (MSO4) patient-controlled analgesia (PCA). A cohort of 229 patients from the preceding 2 years who were treated with MSO4 PCA but not acetaminophen was used as a historical control. Patient demographic characteristics and narcotic use data were extracted from electronic medical records. Student's t test or linear regression was used as appropriate (P< .05). RESULTS: During the first 24-hour postoperative period after LRYGB, narcotic analgesic demand (total PCA demand including nondelivery of narcotic due to lock-out) was reduced by 25% with the concomitant use of i.v. acetaminophen (40.5 versus 30.9 average pushes; P<.05). During the same period, narcotic analgesic dosage requirement was cut down by 20% in the study group (average of 29.9 versus 24.1 mg of MSO4; P<.05). Linear regression analysis confirmed that these changes were independent of age, gender, and body mass index distribution, or type 2 diabetes mellitus. CONCLUSION: Scheduled i.v. acetaminophen reduces the demand for and the requirement of narcotic analgesia after LRYGB. We provide new evidence in support of the routine use of multimodal analgesia that includes scheduled i.v. acetaminophen in the initial 24-hour period after bariatric surgery.

Bile-pancreatic juice exclusion increases cholinergic M3 and CCK-A receptor expression and interleukin-6 production in ligation-induced acute pancreatitis.

BACKGROUND: Using an original model, the Donor Rat Model, we showed that bile-pancreatic juice (BPJ) exclusion from gut exacerbates ligation-induced acute pancreatitis in rats. We also showed that muscarinic cholinergic M3 and CCK-A receptor expression is induced following duct ligation. Increased receptor number potentially could exacerbate cytokine production. We hypothesize that BPJ exclusion is responsible for M3 and CCK-A receptor induction and increased interleukin-6 (IL-6) production. METHODS: M3 and CCK-A receptor expression and IL-6 production were compared in rat pancreata 1 to 3 hours after duct ligation with or without BPJ replacement. RESULTS: Our studies showed that BPJ replacement attenuates duct ligation-induced increases in M3 and CCK-A receptor expression and IL-6 production. CONCLUSIONS: In this model, BPJ exclusion from gut induces M3 and CCK-A receptor expression and increases IL-6 production. In this experimental corollary of gallstone pancreatitis, BPJ exclusion from gut may play a key role in the mechanism of disease pathogenesis.

Cholinergic receptor induction and JNK activation in acute pancreatitis.

BACKGROUND: Cholecystokinin-A (CCK-A) and cholinergic receptor pathways, capable of activating stress kinases p38 mitogen-activated protein kinase (p38(MAPK)) and cJUN N-terminal kinase (JNK), are implicated in the pathogenesis of ligation-induced acute pancreatitis in rats. As ligation-induced acute pancreatitis in rats is associated with CCK-A receptor induction and p38(MAPK) activation, and as receptor induction could amplify acinar hyperstimulation and exacerbate cell stress, we tested the hypothesis that the cholinergic M3 receptor is induced and JNK is activated in this model. METHODS: Cholinergic M3 receptor expression and JNK activation was compared in rats 1, 3, or 24 hours after sham operation or duct ligation. RESULTS: Immunoblot analysis of pancreatic homogenates showed a time-dependent increase in cholinergic M3 receptor protein, total JNK, and phospho-JNK after duct ligation. CONCLUSIONS: There is a rapid and progressive cholinergic M3 receptor induction and JNK activation in ligation-induced acute pancreatitis in rats. These findings may have significance in the mechanism of disease pathogenesis.

Roux-en-Y gastric bypass achieves substantial resolution of migraine headache in the severely obese: 9-year experience in 81 patients.

BACKGROUND: Although migraine headache (MH) is more severe in the obese, the risk of developing MH in the obese population is controversial. The effect of surgical weight loss on morbidly obese patients with MH provides a unique opportunity to evaluate this potential association. METHODS: We analyzed the data from 702 morbidly obese patients who underwent Roux-en-Y gastric bypass (RYGB) from 2000 to 2009. We identified patients with physician-diagnosed MH taking antimigraine medication. RESULTS: The data are presented as the mean ± SEM, with the range in parentheses. Of the 102 patients with preoperative MH, 21 were excluded because they had <12-month follow-up data and 81 were followed up for 38.6 ± 3 months (range 12-123). Of the 81 patients, 90% were women. Their body mass index was 48 ± 1 kg/m(2) (range 37-85), and their age was 40 ± 1 years (range 18-62). After surgical weight loss, clinical improvement in MH was seen in 89% of patients within 5.6 ± .9 months (range 1-36; P < .01, chi-square test), with 57 reporting total resolution and 15 reporting partial resolution (9 experienced no change). Using logistic regression analysis, we showed that the improvement in MH after RYGB was independent of the improvement in migraine-associated co-morbidities, such as sleep apnea, menstrual dysfunction, depression, and anxiety. We also compared patients who developed MH after obesity onset with those who had MH before obesity. The MH after obesity onset group included 51 patients, of whom 48 showed clinical improvement (41 complete, 7 partial, and 3 no improvement). The MH before obesity group included 24 patients, of whom 18 showed clinical improvement (11 complete, 7 partial, and 6 no improvement). The MH after obesity group showed a greater rate of complete resolution of MH after RYGB than did the MH before obesity group (P < .01; chi-square test). CONCLUSIONS: Weight loss after RYGB substantially resolves MH, especially when obesity onset precedes MH onset. It remains to be determined whether RYGB-induced endocrine alterations or a reduction in adipokine burden contribute to migraine improvement.