bluuebunny/crossref_metadata_2025 huggingface dataset:
Sodium-Glucose Cotransporter 2 Inhibitors Improve Pancreatic ß-Cell Function by the Relief of ß-Cell Distress in Japanese Type 2 Diabetes
Authors: YAMAMOTO TSUNEHIKO
Published: June 2018

Sodium-glucose cotransporter 2 inhibitor (SGLT2i) therapies have demonstrated efficacy and safety in the treatment of type 2 diabetes (T2D). Recent studies suggested the potential roles of SGLT2i in the restoration of pancreatic β-cell function. SGLT2i is a new class of antidiabetic agent, independent from insulin action, however, its mechanism are not enough elucidated. We investigated the effects of SGLT2i on pancreatic β-cell function in T2D patients. This open-label, single-arm trial was conducted in our single medical hospital. A total of 30 patients (mean age 57.9±9.0 years, hemoglobin A1c 8.35±1.09%, BMI 29.2±4.5 kg/m2, diabetes duration 9.6±7.0 years) received some kinds of SGLT2i, canagliflozin, dapagliflozin or empagliflozin. Any change in the medication of oral hypoglycemic agents was not prohibited during the period of this trial. After 3 months of treatment, changes in hemoglobin A1c,body weight, fat mass, proinsulin-to-C-peptide ratio (ProINS/CPR, as an indicator of distressed pancreatic β-cell) and secretory units of islets in transplantation index (SUIT, as a marker of pancreatic β-cell function) were evaluated. Mean hemoglobin A1c decreased from 8.35 to 7.39% (p<0.01), and body weight decreased from 81.3 to 79.3 kg (p<0.01), significantly. ProINS/CPR ratio decreased from 0.037 to 0.031 (p=0.022), whereas SUIT index restored from 35.3 to 47.8 (p<0.01). We found a linear negative relationship between δProINS/CPR ratio and δSUIT index (r(2)=0.338, p<0.01). Multivariate analysis revealed that only baseline ProINS/CPR ratio was independently associated with SUIT index restoration (β=0.673, p<0.01), whereas older age, longer diabetic duration, body weight, fat mass, hemoglobin A1c were not associated. These results suggest that SGLT2i improves pancreatic β-cell function by the relief of β-cell distress, independent of the efficacy of glycemic control and body weight loss effect.

Disclosure

T. Yamamoto: None.
Risk Factors for Major Atherosclerotic Cardiovascular Events (MACE) in Type 1 Diabetes (T1D)—The Pittsburgh Epidemiology of Diabetes Complications (EDC) Study
Authors: MILLER RACHEL G. , ORCHARD TREVOR J.
Published: June 2018

The Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications follow-up study (EDIC) recently reported that after age mean HbA1c was the strongest predictor of MACE over 27 year of follow-up. The DCCT/EDIC cohort had a short T1D duration at baseline (mean 6 yr) and those with high blood pressure or cholesterol were excluded so it is unclear if these results apply to longer T1D durations and without risk factor exclusion. We thus replicated these analyses in the Pittsburgh EDC study a prospective cohort study of childhood onset (<17 yr) T1D with 25 year of follow-up and similar age (mean 27 year in both studies) but longer T1D duration (mean 18 yr) at baseline. EDC participants were diagnosed 1950-1980 (n=658 49% women) and examined at 1986-88 baseline. Follow-up exams occurred at 2, 4, 6, 8, 10, 18 and 25 years. MACE incidence (CVD death, MI, stroke) was ascertained by death certificate or self reported and confirmed with medical records. Participants with prevalent CVD were excluded (n=54). Baseline (BL), time varying updated mean (UM) and time varying most recent (MR) risk factors were assessed in Cox models as in DCCT/EDIC. In EDC 18% (107) developed MACE vs. 6% in DCCT/EDIC. The final multivariable model for MACE comprised BL T1D duration (HR 1.1, p<.001), MR albumin excretion rate (AER) (HR 1.3, p<.001), UM SBP (HR 1.03, p<.001), BL smoking (HR 1.9, p=0.003), UM LDLc (HR 1.01, p=0.03) and UM HbA1c (HR 1.2, p=0.03). In DCCT/EDIC the HbA1c effect size was larger while T1D duration, UM SBP, MR (not UM as in EDC) LDLc and MR (not BL as in EDC) smoking predicted with similar effect sizes. ACE inhibitors (protective) and pulse rate also predicted MACE in DCCT/EDIC. While AER was a strong predictor in EDC no renal markers were significant in DCCT/EDIC. These results suggest that at longer T1D duration much of the HbA1c effect on MACE risk is mediated through other factors as recently reported by DCCT/EDIC.

Disclosure

R.G. Miller: None. T.J. Orchard: None.
IGFBP2 Is Increased after Gastric Bypass in Humans—Potential Impact on Hepatic Metabolism
Authors: YUCHI YIXING , CAI WEIKANG , TAKAGI TOKIYO , PAN HUI , DREYFUSS JONATHAN , FOSTER KATHLEEN , VERNON ASHLEY H. , SIMONSON DONALD C. , GOLDFINE ALLISON , HOEFLICH ANDREAS , PATTI MARY E.
Published: June 2018

To identify molecular mechanisms contributing to postoperative metabolic improvements after Roux-en-Y gastric bypass (RYGB), we performed comprehensive proteomic analysis of fasting human plasma samples obtained from the SLIMM-T2D longitudinal clinical trial, which randomized obese individuals with T2D to RYGB surgery or a one-year intensive medical diabetes and weight management (DWM) program, and followed them for 3 years. Somalogic proteomic analysis was performed on plasma collected in the fasting state at baseline and during longitudinal follow-up, and proteins differentially abundant in RYGB vs. DWM at each time point were identified. The protein with highest magnitude of differential abundance at 3 years was insulin-like growth factor binding protein 2 (IGFBP2), upregulated by 2.2-fold in RYGB vs. DWM (p=4.37E-06); differences were confirmed by ELISA. IGFBP2 inversely correlated at 3 years with BMI (r=-0.74, p=5.31E-05) and HbA1c (r=-0.68, p=0.00004). Notably, IGFBP2 levels were increased at the first postoperative study visit (10% weight loss) following RYGB or at similar weight loss for the DWM group, suggesting an early weight-independent contribution.

IGFBP2 is predominantly expressed in liver and upregulated after RYGB in mice (2.8-fold at 8 weeks, GSE68812). To identify IGFBP2-dependent mechanisms contributing to improved hepatic metabolism, we overexpressed mouse IGFBP2 or control vector in mouse AML12 hepatocytes, achieving a 6-fold increase in IGFPB2 protein. qPCR revealed 15-30% downregulation of lipogenic genes (e.g., Fasn, Srebp1) with a 2-fold increase in expression of genes regulating fatty acid oxidation (e.g., Ppara, Ppargc1a). Analysis of metabolism (Seahorse flux analyzer) revealed increased fatty acid oxidation (3-fold, p<0.01 for IGFBP2 vs. control).

In conclusion, increased IGFBP2 expression may contribute to improved hepatic lipid oxidative metabolism, and thus induce systemic metabolic improvement after RYGB surgery.

Disclosure

Y. Yuchi: None. W. Cai: None. T. Takagi: None. H. Pan: None. J. Dreyfuss: None. K. Foster: None. A.H. Vernon: None. D.C. Simonson: Advisory Panel; Self; GI Windows, Inc.. Stock/Shareholder; Self; GI Windows, Inc.. Stock/Shareholder; Spouse/Partner; Phase V Technologies, Inc. A. Goldfine: Employee; Self; Novartis AG. A. Hoeflich: None. M.E. Patti: Research Support; Self; Janssen Pharmaceuticals, Inc.. Other Relationship; Self; Xeris Pharmaceuticals, Inc.. Research Support; Self; Ethicon US, LLC., Coviden, MedImmune. Other Relationship; Self; Novo Nordisk Inc., XOMA Corporation, AstraZeneca, Nestlé. Research Support; Self; Dexcom, Inc.. Consultant; Self; Eiger BioPharmaceuticals.
The SGLT2 Inhibitor Canagliflozin Induces Catabolic Transcriptional and Metabolic Switching and Increases FGF-21 in Mice with Dietary Obesity
Authors: OSATAPHAN SORAVIS , MACCHI CHIARA , SALES VICENCIA , KOZUKA CHISAYO , CHIMENE-WEISS JEREMY I. , TANGJAROENPAISAN YANIN , MORNINGSTAR JORDAN , GERSZTEN ROBERT , PATTI MARY E.
Published: June 2018

Given the impact of SGLT2 inhibitors to reduce overall mortality and CV risk in T2D, improved understanding of cellular and transcriptional mechanisms responsible for metabolic effects is required. We fed C57BL/6J mice a 60% high fat diet (HFD) for 4 weeks prior to assignment to one of 3 groups: (1) 60% HFD, (2) HFD with canagliflozin (CANA, 25 mg/kg/day), and (3) HFD weight-matched (WM) to CANA via caloric restriction. Mice were analyzed after 4-8 weeks. CANA reduced fasting glucose by 47% (P<0.0001), improved glucose tolerance, and 25% lower body weight vs. HFD (p<0.0001). CANA promoted shift toward lipid utilization, with respiratory quotient <0.7 even during feeding, and a 3.7 and 2.0-fold increase in plasma and liver β-hydroxybutyrate (both p<0.01 vs. HFD). In parallel, liver glycogen and cholesterol were reduced by 55% and 28%, and triglycerides were shifted toward polyunsaturated species.

To identify potential mechanisms responsible for these fasting-like phenotypes, we analyzed the molecular impact of CANA. Liver transcriptomic analysis revealed marked downregulation of lipogenesis, glycolysis, and steroid synthesis pathways (p<0.01), while the lipid oxidative regulatory genes PPARα and PGC1α were increased by 2.8 and 4-fold, respectively. CANA significantly increased hepatic FAD+ (2.4-fold) and AMP (1.3-fold), in parallel with a 12-fold increase in AMPK phosphorylation and 50% reduction in Tor-dependent phosphorylation of S6. Hepatic gene expression of FGF-21, a hormonal regulator of fatty acid oxidation and ketogenesis, was increased by 4.5-fold, with parallel 2.2-fold increase in plasma FGF-21 in CANA-treated mice (p<0.vs. HFD for both). These effects were independent of insulin sensitivity or glucagon signaling. Collectively, these data demonstrate CANA induction of a fasting-like state by coordinated transcriptional-metabolic reprogramming, and identify FGF-21 as a potential molecular metabolic switch.

Disclosure

S. Osataphan: None. C. Macchi: None. V. Sales: None. C. Kozuka: None. J.I. Chimene-Weiss: None. Y. Tangjaroenpaisan: None. J. Morningstar: None. R. Gerszten: None. M.E. Patti: Research Support; Self; Janssen Pharmaceuticals, Inc.. Other Relationship; Self; Xeris Pharmaceuticals, Inc.. Research Support; Self; Ethicon US, LLC., Coviden, MedImmune. Other Relationship; Self; Novo Nordisk Inc., XOMA Corporation, AstraZeneca, Nestlé. Research Support; Self; Dexcom, Inc.. Consultant; Self; Eiger BioPharmaceuticals.
The Association of Impaired Fasting Glucose and Serum Fibroblast Growth Factor-21 (FGF-21)
Authors: KIM HANBYUL , CHO HOCHAN
Published: June 2018

Prediabetes includes impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) and there is a strong probability that prediabetes will lead to diabetes mellitus (DM). Serum fibroblast growth factor 21 (FGF-21) is known to increase as a compensatory response to metabolic imbalance under conditions such as obesity, metabolic syndrome, and DM. This study aimed to identify the relationship of serum FGF-21 to prediabetes and to biomarkers of related metabolic diseases. Three hundred five Korean adult patients participated in a cohort study from June 2012 to December 2015. Study subjects comprised of those with normal glucose tolerance(n=165), prediabetes(IFG, IGT, n=87) and type 2 diabetes(n=54). The biochemical parameters were analyzed using auto-analyzer, and the level of FGF-21 was estimated using an ELISA kit. The analysis revealed that FGF-21 levels were significantly higher in the Prediabetes group compared to those in the normal group(193.94±10.62, 343.49±60.94)(P=0.004). One-way ANCOVA was conducted on the correlations between serum FGF-21 levels and other parameters, dyslipidemia(F=7.428, P=0.007), HbA1c(F=11.874, P=0.001) was show statistical significance.

In conclusion, our results revealed that serum FGF-21 level serves as a marker predicting IFG.

Disclosure

H. Kim: None. H. Cho: None.
Low Hepatic Fat and Stearoyl-CoA Desaturase Activity Contribute to Paradoxically Normal Triglyceride-Rich Lipoproteins in Insulin Resistant Black Women—The Federal Women Study
Authors: CHUNG STEPHANIE T. , GALVAN-DE LA CRUZ MIRELLA , BERNSTEIN SHANNA , ONUZURUIKE ANTHONY , MATTHAN NIRUPA R. , OUWERKERK RONALD , MABUNDO LILIAN , SAMPSON MAUREEN L. , COURVILLE AMBER B. , GHARIB AHMED M. , LICHTENSTEIN ALICE H. , REMALEY ALAN , SUMNER ANNE E.
Published: June 2018

In black women, triglycerides (TG) are paradoxically normal in the presence of insulin resistance (IR). This TG paradox while partially explained by low visceral fat, might be further clarified by delineating the association of triglyceride rich lipoprotein (TRLP) subclasses with hepatic fat, IR and stearoyl-CoA enzyme activity (SCD-116, a marker of de novo lipogenesis). We hypothesized that fasting TRLP, hepatic fat and SCD-116 activity would be lower in black vs. white women. In 122 federally employed women without diabetes, we compared fasting TRLP number and size (measured with NMR) in 73 black (58 African American and 15 African immigrant) and 49 white; age 44±10 (mean±SD), range 24- 62y; BMI 30.0±5.6, range 20.3-45.2 kg/m2. Hepatic and visceral fat were measured by proton MRS. RBC fatty acid profiles were measured by gas chromatography (mol %) and used to estimate SCD-116 (16:1n-7/to 16:0). Total, large, medium and small TRLPs, visceral fat, SCD-116 were similar in blacks and lower than in whites before and after adjustment for age and body fat (P<0.001). Blacks had lower SI (2.28 (1.52) vs. 2.74 (2.81), median(IQR) P=0.05, and hepatic fat (0.7 (1.1) vs. 1.2 (2.1), P=0.03. SCD-116 correlated with hepatic fat (r=0.34, P<0.01). Habitual physical activity, dietary fatty acid profiles were similar (P>0.1). In multivariate linear models, age, SCD-116, body fat, visceral fat and SI, but not race or liver fat, were independently associated with total TRLP (adjR2=0.44, P<0.01). Medium and large TRLP number was independently predicted by visceral fat and SCD-116 activity (adjR2=0.37, P<0.01); race was the only predictor for small TRLPs (adjR2=0.14, P<0.01). Therefore, lower hepatic fat and SCD-116 maybe important contributors to the paradoxically normal fasting TRLP in insulin resistant black women.

Disclosure

S.T. Chung: None. M. Galvan-De La Cruz: None. S. Bernstein: None. A. Onuzuruike: None. N.R. Matthan: None. R. Ouwerkerk: None. L. Mabundo: None. M.L. Sampson: None. A.B. Courville: None. A.M. Gharib: None. A.H. Lichtenstein: None. A. Remaley: None. A.E. Sumner: None.
Canagliflozin, an SGLT2 Inhibitor, Prevents Development of Hepatocellular Carcinoma (HCC) from Nonalcoholic Steatohepatitis (NASH) in a Mouse Model of NASH-HCC Under Diabetic State
Authors: JOJIMA TERUO , WAKAMATU SYO , IIJIMA TOSHIE , USUI ISAO , ASO YOSHIMASA
Published: June 2018

Nonalcoholic steatohepatitis (NASH) can result in liver cirrhosis and hepatocellular carcinoma (HCC). Several studies have shown that some SGLT2 inhibitors alleviate hepatic steatosis or steatohepatitis in type 2 diabetic mice or rats. First, we investigated the effects of canagliflozin (CANA), an SGLT2 inhibitor, on steatohepatitis and fibrosis in a novel diabetes nonalcoholic steatohepatitis (NASH) -HCC progression model mice. We next investigated inhibitory effects of CANA on development of HCC in this model mice. Mice aged 5 weeks were divided into two groups (vehicle and CANA 30 mg/kg) and fed for 3 more weeks. The histological nonalcoholic fatty liver disease activity score (NAS) was lower in the CANA group than in the vehicle group. The expression of type 1 and 3 collagen mRNA was reduced in the CANA group. Mice aged 5 weeks were divided into three groups of 9 animals: vehicle, CANA initial administration 30mg/kg (5 to 9 W), CANA continuous administration 30 mg/kg (5 to 16W). At the age of 16 weeks, the NAS was significantly lower in the CANA continuous administration group than in the vehicle or the CANA initial administration groups. The number of hepatic tumors was significantly smaller in the CANA continuous administration group than in the vehicle group. Immunohistochemistry showed that expression of glutamine synthetase, a marker of HCC, was reduced in the CANA continuous administration group compared with the vehicle group. Furthermore, the CANA continuous administration significantly decreased expression of mRNAs for α-fetoprotein, a tumor maker of HCC, compared with the vehicle administration.

In conclusion, canagliflozin attenuates development of NASH showing anti-steatotic and anti-inflammatory effects, and prevents progression of HCC from NASH.

Disclosure

T. Jojima: Research Support; Self; mitsubishi tanabe phama corporation. S. Wakamatu: None. T. Iijima: None. I. Usui: None. Y. Aso: None.
Lactobacillus Pentosus Strain S-PT84 Attenuates Insulin Resistance and Steatohepatitis by Maintaining Gut Permeability and Polarizing M2 Macrophages
Authors: SAKAI YURIKO , NAGASHIMADA MAYUMI , OTA TSUGUHITO
Published: June 2018

Obesity or high-fat diet enhances gut permeability and metabolic endotoxemia, which can trigger insulin resistance and NASH. However, there are few promising treatments targeting lipotoxicity-mediated endotoxemia in NASH. The Lactobacillus pentosus strain S-PT84 has immunomodulatory functions including Th1/Th2 balance modulatory effects and natural killer (NK)/NKT cell activation. In this study, we examined the effect of S-PT84 on diet-induced NASH. C57BL/6 mice were fed a high-cholesterol/high-fat diet (CL) alone or with 1×1010 S-PT84 (CL + S-PT) for 22 weeks. We quantified intrahepatic immune cells using a fluorescence-activated cell sorter (FACS). S-PT84 administration improved hepatic steatosis by decreasing TG and FFA levels by 34% and 37%, respectively. S-PT84 also inhibited the development of hepatic inflammation and fibrosis, lowering F4/80+ macrophage/Kupffer cell infiltration and the hydroxyproline content of the liver. S-PT84 administration in mice fed a CL diet led to improved hyperinsulinemia as well as enhanced hepatic insulin signal assessed by phospho-Akt. FACS analysis revealed that mice fed the CL+S-PT had 71% more CD11c-CD206+ M2 macrophages than mice fed the CL diet, resulting in a predominance of the M2 over the M1 macrophage population. S-PT84, however, showed little effect on NK/NKT cell and T regulatory cell populations in the liver. Furthermore, CL diet increased intestinal permeability as measured with the carboxyfluoresce assay and increased plasma lipopolysaccharide binding protein (LBP) levels. S-PT84 diminished increased intestinal permeability and plasma LBP levels. Additionally, S-PT84 reduced IL-17 producing T cells and increased ZO-1, occludin, and claudin proteins constituting tight junction in colon.

In conclusion, S-PT84 treatment attenuated lipotoxicity-induced insulin resistance and NASH by maintaining gut permeability and polarizing M2 liver macrophages.

Disclosure

Y. Sakai: None. M. Nagashimada: None. T. Ota: None.
Development of In Vitro NASH Model with Mechanically Compliant Substrate
Authors: MORISHIMA MASAKI , HORIKAWA KAZUKI , FUNAKI MAKOTO
Published: June 2018

Although a sedentary lifestyle is known to play a role in nonalcoholic steatohepatitis (NASH), understanding of the molecular mechanism of NASH development is incomplete and effective treatment is still greatly sought. Part of this challenging situation in tackling NASH is a lack of an appropriate in vitro hepatocyte culture that reproduces in vivo cellular functions ex vivo. Emerging evidence suggests that matching the stiffness of substrates with that of tissues helps reproducing in vivo functions of cells derived from them. Thus, we hypothesized that primary hepatocytes on 500 Pa polyacrylamide (PAA) gels, whose stiffness matches that of the liver, may exhibit steatosis and a pro-inflammatory response when treated with either fructose or palmitate to model over-nutrition. To this end, rat primary hepatocytes were seeded on either 500 Pa PAA gels or glass coverslips, which represent a conventional but unphysiological stiff culture device. Cells were cultured in low glucose Dulbecco’s Modified Eagle’s medium, whose glucose concentration matches the normal blood glucose level, with or without addition of 5.5 mM fructose or 0.5 mM palmitate. Addition of fructose or palmitate induced lipid accumulation in cells on 500 Pa gels and increased ROS (reactive oxygen species) accumulation in hepatocytes on 500 Pa PAA gels, but not in hepatocytes on glass. Fructose or palmitate treatment also caused HMGB1 (High Mobility Group Box 1) secretion by hepatocytes, implicating a proinflammatory response by these cells. These results suggest that exposure of hepatocytes on a mechanically compliant substrate to either fructose or palmitate may serve as an excellent ex vivo model of the initial phase of NASH development by showing ability to initiate an inflammatory process.

Disclosure

M. Morishima: None. K. Horikawa: None. M. Funaki: Research Support; Self; Otsuka Holdings Co., Ltd., The Knowledge Cluster from the Ministry of Education, Science, and Culture of Japan. Board Member; Self; Mechanogenic C.C..
The Role of Adipocyte Fatty Acid Binding Protein in the Development of Liver Fibrosis
Authors: WU XIAOPING , SHU LINGLING , LAM KAREN S. , XU AIMIN , HOO RLC
Published: June 2018

Liver fibrosis is the result of chronic liver injury and the first step toward the development of liver cirrhosis and hepatic carcinoma. Under the stress of damage factors, quiescent hepatic stellate cells (qHSCs) trans-differentiate into myofibroblast-like cells, and take the main role of extracellular matrix secretion contributing to the development of liver fibrosis. In recent clinical study, circulating level of A-FABP, was found to positively correlate with the stages of liver fibrosis and liver cirrhosis. Here, we investigate the role of A-FABP in the development of liver fibrosis. A-FABP knockout (A-FABP KO) mice and their wild type (WT) littermates were subjected to bile duct ligation (BDL) for two weeks to induce liver fibrosis. Plasma and hepatic A-FABP were significantly elevated in BDL treated WT mice. Liver sinusoidal endothelial cell (LSEC) was identified as the major cellular source of hepatic A-FABP in response to BDL. In the BDL treated groups, comparing to the WT mice, A-FABP KO mice showed significantly reduced collagen formation and HSC activation which were accompanied by an attenuated induction of hepatic expression of transforming growth factor beta 1 (TGFβ1), a central regulator in hepatic fibrogenesis. As the LSECs and HSCs are closely attached to each other, we hypothesize that LSECs-derived A-FABP may act in a paracrine manner to stimulate the expression of TGFβ1 in HSCs. Our in vitro study demonstrated that treatment of recombinant A-FABP protein (rA-FABP) significantly induced the expression of TGFβ1 in primary HSCs. Mechanistically, BDL induces the release of A-FABP from LSECs which stimulates the TGFβ1 gene transcription through enhancing the activator protein-1 (AP-1) activity on its promoter via upregulating the phosphorylation of c-Jun, a component of AP-1.

In conclusion, A-FABP contributes to the development of liver fibrosis via enhancing the expression of TGFβ1 in HSCs.

Disclosure

X. Wu: None. L. Shu: None. K.S. Lam: None. A. Xu: None. R. Hoo: None.
cGMP-Dependent Protein Kinase I (cGKI) Modulates Human Hepatic Stellate Cell Activation
Authors: FRANKO ANDRAS , KOVAROVA MARKETA , WAGNER ROBERT , WEIGERT CORA , FEIL ROBERT , FEIL SUSANNE , HAERING HANS-ULRICH , LUTZ STEFAN Z. , PETER ANDREAS
Published: June 2018

Background: Nonalcoholic fatty liver disease and hepatic insulin resistance precede diabetes and may further develop into nonalcoholic steatohepatitis and liver fibrosis/cirrhosis. The activation of hepatic stellate cells (HSC), which is characterized by the loss of retinyl-ester stores, plays a crucial role in the pathophysiology of this process. Since cGMP-dependent protein kinase I (cGKI) deficient (cGKI-KO) mice displayed hepatic insulin resistance and disturbed glucose metabolism, as well as, cGKI is only detected in HSC but not in hepatocytes, we hypothesized that cGKI modulates HSC activation and its metabolic consequences.

Methods: First, retinol storage and gene expression were studied in cGKI-KO mice. Second, we investigated the effects of cGKI-silencing on gene expression and cellular activation in the human stellate cell line LX2. Finally, cGKI expression was investigated in human liver biopsies covering a wide range of liver fat content.

Results: Retinyl-ester level in the liver of cGKI-KO mice was lower compared to wild type animals, which was associated with increased inflammatory gene expression. Activation of LX2 cells showed increased α-smooth muscle actin and matrix metalloproteinase 2 expression, which was augmented by silencing cGKI. On the other hand, activation of LX2 cells by TGFβ suppressed cGKI expression. Furthermore, we detected a negative correlation between cGKI mRNA and liver fat content in human biopsies.

Conclusions: The lower mRNA level of cGKI either in TGFβ activated LX2 cells or in liver biopsies with high fat content suggest that cGKI function might be impaired during HSC activation. Furthermore, the higher expression of inflammatory genes and low retinyl-ester levels in cGKI-KO mice as well as the higher levels of activation markers in cGKI-silenced LX2 cells indicate that cGKI inhibits HSC activation. Since cGKI is a downstream target of nitric oxide (NO), it is conceivable that NO may exert protective effects inhibiting liver fibrosis via cGKI.

Disclosure

A. Franko: None. M. Kovarova: None. R. Wagner: None. C. Weigert: None. R. Feil: None. S. Feil: None. H. Haering: None. S.Z. Lutz: None. A. Peter: None.
Short-Term Exercise Improves Hepatic Insulin Extraction in Individuals with Nonalcoholic Fatty Liver Disease
Authors: HARI ADITHYA , FEALY CIARAN E. , KIRWAN JOHN P.
Published: June 2018

Nonalcoholic fatty liver disease (NAFLD), the hepatic component of insulin resistance syndrome, is pathophysiologically associated with lower hepatic insulin clearance, lower fat oxidation and increased carbohydrate oxidation in a post-absorptive state. Aerobic exercise is purported to be beneficial in NAFLD. To better understand the mechanisms through which short-term, moderate intensity aerobic exercise training could exert these benefits, 13 obese, sedentary adults (age: 58±3.4 years, BMI: 34.3±1.1 kg/m2; means±SEM) with NAFLD (>5% Intra-hepatic lipid content assessed by 1H MR spectroscopy) were recruited into a 7-day exercise training program (treadmill walking for 60 mins, 5 days per week, at 80-85% maximum heart rate). Participants maintained their normal dietary patterns. Pre- and post-intervention assessments included a 75-gm OGTT, CT scans, VO2max and indirect calorimetry. Insulin sensitivity (ISI) was estimated using Soonthorpun model. Hepatic Insulin Extraction (HIE) was calculated as the molar difference in AUCs for insulin and C-peptide (HIE=1-(AUCInsulin÷AUCC-Pep)). The intervention yielded an ∼9% increase in VO2max and HIE (P<0.01). Whole-body insulin sensitivity increased by ∼43% (P<0.05). There was a significant increase in basal fat oxidation (pre vs. post: 47±6 vs. 65±6 mg/min, P<0.05) and decrease in basal carbohydrate oxidation (160±20 vs. 112±15 mg/min, P<0.05). After the intervention, HIE was positively correlated with adiponectin (r=0.56, P<0.05) and negatively correlated with TNF-α (r=-0.78, P<0.001). The change in ISI was negatively correlated with change in subcutaneous abdominal fat depot (r=-0.55, P=0.05). These data suggest that exercise may quickly reverse the pathophysiology of NAFLD by improving

HIE and fasting substrate oxidation. The cardio-metabolic benefit of exercise in individuals with NAFLD is potentially mediated through changes in HIE.

Disclosure

A. Hari: None. C.E. Fealy: None. J.P. Kirwan: None.
Insulin Signaling in Adipocytes Controls Systemic Insulin Sensitivity through the 5-LO-LTB4 Axis
Authors: HOSOOKA TETSUYA , OGAWA WATARU
Published: June 2018

Although adipocytes are major targets of insulin, the influence of impaired insulin action in adipocytes on metabolic homeostasis has been unclear. To provide insight into the role of insulin action in adipocytes, we generated mice that lack 3'-phosphoinositide-dependent kinase1 (PDK1) specifically in adipocytes (A-PDK1KO mice). These mice manifest impairment of metabolic actions of insulin in adipose tissue and a reduction in adipose tissue mass. The mice developed insulin resistance, glucose intolerance, and hepatic steatosis, all of which were markedly attenuated by additional ablation of FoxO1 specifically in adipocytes without an effect on adipose tissue mass, indicating that the PDK1-FoxO1 axis in adipocytes plays an important role in systemic metabolic homeostasis through a mechanism independent of the regulation of adipose tissue mass. Neither circulating levels of adiponectin and leptin nor inflammation in adipose tissue differed between A-PDK1KO mice and adipocyte-specific PDK1/FoxO1 deficient mice (A-PDK1/FoxO1KO mice), indicating that those factors did not account for the difference in metabolic phenotypes of the two genotypes of mice. Microarray and lipidomics analyses revealed that leukotriene B4 (LTB4) levels in plasma and in adipose tissues as well as the expression of 5-lipoxygenase (5-LO), a rate limiting enzyme for LTB4 production, in adipose tissues were increased and normalized in A-PDK1KO and A-PDK1/FoxO1KO mice, respectively. Administration of a 5-LO inhibitor reduced plasma levels of LTB4 and ameliorated insulin resistance and glucose intolerance in A-PDK1KO mice. Furthermore, insulin was found to inhibit LTB4 production through downregulation of 5-LO expression via the PDK1-FoxO1 pathway in isolated adipocytes. These results thus indicate that insulin signaling via the PDK1-FoxO1 pathway negatively regulates the production of LTB4 through the suppression of 5-LO in adipocytes and thereby maintains systemic insulin sensitivity.

Disclosure

T. Hosooka: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc. W. Ogawa: Research Support; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Abbott.
Impact of Type 1 Diabetes on 24-Hour Energy Expenditure and Metabolic Flexibility
Authors: CARNERO ELVIS A. , CORBIN KAREN D. , BOCK CHRISTOPHER P. , SMITH STEVEN R. , PRATLEY RICHARD E.
Published: June 2018

Type 1 diabetes (T1D) is associated with an increase in resting metabolic rate, but the impact of T1D on other components of 24-hour energy expenditure (EE) and metabolic flexibility (MF) is not known. We measured 24-hour EE, its components and substrate oxidation rates in 11 patients with T1D and 12 nondiabetic, age and BMI matched controls (HC) using whole room calorimetry. MF was defined as the respiratory quotient (RQ) kinetic response after ingesting a standard high CHO breakfast. Briefly, the kinetics between the lowest RQ pre-breakfast and the highest RQ after breakfast were analyzed by a simple linear regression between time (1-minute resolution) and RQ units (RQUnits). Subjects with T1D had marginally higher 24-hour EE and higher 24-hour non-exercise EE, but sleeping EE and basal EE were not significantly different (Table 1). There were no differences in 24-h respiratory quotient (RQ) or sleeping RQ, but MF during the breakfast meal was significantly lower in T1D vs. HC (p=0.042). Among patients with T1D, MF was related to the glycemic response to breakfast. These data suggest that T1D is characterized by alterations in EE and MF. These results have implications for glycemic and weight management among patients with T1D.

Disclosure

E.A. Carnero: None. K.D. Corbin: None. C.P. Bock: None. S.R. Smith: None. R.E. Pratley: Other Relationship; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eisai Inc., GlaxoSmithKline plc., Janssen Pharmaceuticals, Inc., Lexicon Pharmaceuticals, Inc., Ligand Pharmaceuticals, Inc., Eli Lilly and Company, Merck & Co., Inc., Novo Nordisk Inc., Pfizer Inc., Sanofi-Aventis, Takeda Development Center Americas, Inc..
Relating Disinhibited Eating Behaviors to Resting State Functional Connectivity in Young Children
Authors: SHAPIRO ALLISON L.B. , JOHNSON SUSAN L. , MOHL BRIANNE , WILKENING GRETA , LEGGET KRISTINA T. , DABELEA DANA , TREGELLAS JASON R.
Published: June 2018

The prevalence of obesity among children in the United States is alarming, with recent work implicating disinhibited eating behaviors (DEBs) as a potential pathway toward obesity development. DEBs have been documented among young children, and are associated with longitudinal weight gain. However, the underlying neurobiology of DEBs in young, healthy weight children, prior to obesity development, remains unknown. This study investigated the relationship between DEBs and intrinsic neuronal connectivity in young children. We tested the hypothesis that greater DEBs would be positively associated with higher neuronal connectivity in the default mode network (DMN) and the salience network, and lower connectivity in the executive control network. The Eating in the Absence of Hunger paradigm was implemented to measure DEBs, with post-lunch calories consumed from highly palatable foods used as our main predictor. Resting state functional magnetic resonance imaging was used to examine neuronal connectivity within the networks of interest. Eighteen typically developing, healthy weight children (mean age = 5.8 years; BMI z-score = -0.6) were included in this analytic sample. Independent component analysis was used to isolate brain networks of interest. Associations between calories consumed and the three networks of interest were examined with second-level general linear models. A significant positive association was observed between calories consumed and functional connectivity in anterior cingulate cortex, a major anterior DMN hub (ACC; x=-6, y=14, z=41; t=5.23; p < 0.01, corrected). No other associations were significant. While preliminary, our results are consistent with previous studies in adults relating both DEBs and obesity status to altered neuronal response in the ACC. Our data suggest that aspects of the neurobiology of DEB are detectable in young, healthy weight children, providing a potential tool to better understand the development of obesity in this population.

Disclosure

A.L.B. Shapiro: None. S.L. Johnson: None. B. Mohl: None. G. Wilkening: None. K.T. Legget: None. D. Dabelea: None. J.R. Tregellas: None.
Sensory Innervation of the Pancreatic Islet
Authors: MAKHMUTOVA MADINA , WEITZ JONATHAN , DIAZ RAYNER RODRIGUEZ , ALMACA JOANA , BERNAL-MIZRACHI ERNESTO , CAICEDO ALEJANDRO
Published: June 2018

Sensory innervation of viscera is an important component for proper maintenance of body homeostasis. Visceral stimuli are detected by free nerve endings of the vagus nerve and are transmitted to the hindbrain via sensory neurons. However, the signals that activate vagal sensory neurons in the periphery are not known. The objective of this study is to identify and characterize the population of vagal sensory neurons that innervates the pancreas. Using immunohistochemistry for sensory neuronal marker substance P, we show that sensory innervation targets islet periphery. Upon islet damage (in NOD model or following streptozotocin (STZ) treatment), density of islet sensory innervation increases. Expression of the immediate early gene c-Fos, shows that hindbrain neurons in the nucleus of the solitary tract (NTS) respond to severe islet inflammation induced by STZ. We assessed response profile of pancreatic sensory neurons using in-vivo calcium imaging of mouse vagal sensory ganglion (nodose). This method allows us to monitor in real time the response profile of sensory neurons and identify pancreas-specific subpopulations by chemical stimulation of the exteriorized pancreas. We have identified sensory neurons that respond to pancreatic application of serotonin (5HT) and cholecystokinin (CCK). The observed response profile suggests that these neuronal populations are tuned to sense differentially endocrine and exocrine pancreas. While endocrine sensory neurons are sensing local 5HT that is co-released with insulin, exocrine neurons sense CCK a hormone that stimulates release of digestive enzymes. Altogether our data suggest that pancreatic sensory neurons could be important regulators of pancreatic physiology. By taking a snapshot of endocrine and exocrine pancreatic microenvironments and sending this information to the brain, sensory neurons might trigger feedback loops and help the organ to be tuned to physiological needs.

Disclosure

M. Makhmutova: None. J. Weitz: None. R. Rodriguez Diaz: None. J. Almaca: None. E. Bernal-Mizrachi: None. A. Caicedo: None.
Westernized Diet–Induced Insulin Resistance in Mice Is Associated with Focal Duodenal Hyperplasia
Authors: GHOSH SOUMITRA , RUBINO FRANCESCO , WISMANN PERNILLE , RIGBOLT KRISTOFFER , RAJAGOPALAN HARITH , MAGGS DAVID
Published: June 2018

Westernized diet (WD; high fat and sugar) induces an insulin resistant state associated with obesity and type 2 diabetes (T2D). Duodenal exclusion surgery in obese T2D patients implicates the duodenum as a key GI region involved in insulin resistance. To identify adaptive changes of pathophysiological relevance, detailed analyses of the GI tract was undertaken following exposure of mice to WD. Metabolic indices and stereological characteristics of the whole gut, mucosal surface and transcriptome were investigated in C57BI/6J male mice fed either chow (lean) or WD (60% fat; 20% sugar) for 7 or 13 weeks (10 mice/cohort). Compared to lean, WD gained more weight and had higher plasma glucose, insulin and total cholesterol (Table) with differences greater at 13 vs. 7 weeks. Unlike other intestinal segments, focal hyperplasia was observed in the duodenum with increased weight and surface area (∼40%). The hyperplastic duodenum was characterized by increased chromogranin-A staining of enteroendocrine (EE) cells. Transcriptomic analysis revealed differences between WD and lean groups (both 7 and 13 weeks) with enrichment for genes involved in lipid and glucose metabolism. Exposure to WD induces adaptive responses in duodenal mucosa, EE cell population, and transcriptome. These findings suggest a potential role of the duodenum in insulin resistance and may explain the insulin-sensitizing effect of duodenal exclusion.

Disclosure

S. Ghosh: Consultant; Self; Fractyl Laboratories, Inc. F. Rubino: Advisory Panel; Self; Fractyl Laboratories, Inc.. Consultant; Self; Fractyl Laboratories, Inc., Ethicon US, LLC.. Speaker's Bureau; Self; Ethicon US, LLC.. Consultant; Self; Medtronic. Advisory Panel; Self; GI Dynamics Inc.. Consultant; Self; GI Dynamics Inc.. Speaker's Bureau; Self; Novo Nordisk Inc.. Research Support; Self; Ethicon US, LLC.. P. Wismann: None. K. Rigbolt: Employee; Self; Gubra. Stock/Shareholder; Self; Gubra. H. Rajagopalan: Stock/Shareholder; Self; Fractyl Laboratories, Inc.. Board Member; Self; Fractyl Laboratories, Inc.. Employee; Self; Fractyl Laboratories, Inc. D. Maggs: Stock/Shareholder; Self; Fractyl Laboratories, Inc.. Employee; Self; Fractyl Laboratories, Inc.. Stock/Shareholder; Spouse/Partner; Gelesis. Employee; Spouse/Partner; Gelesis.
The Sarcoplasmic Reticulum Calcium ATPase Pump Is a Major Regulator of Whole–Body Glucose Metabolism
Authors: MARIA ZAHRA , CAMPOLO ALLISON , GRAY SHANELL SHOOP , HARTSON STEVEN , LACOMBE VERONIQUE
Published: June 2018

The heart is a very active metabolic organ which exerts endocrine effects by secreting natriuretic peptides. However, its role in the regulation of whole-body metabolism has received scarce attention. Therefore, we hypothesized that cardiac-specific overexpression of the sarcoplasmic reticulum calcium ATPase (SERCA) pump, which tightly regulates cytosolic calcium, modulates whole-body glucose homeostasis during healthy and diabetic states. Diabetes was induced by streptozotocin injections in wild type (WT) and transgenic (TG) mice overexpressing the SERCA pump in the heart (n=4-10/group). Translocation of glucose transporters (GLUTs) was measured in insulin-sensitive tissues using a photolabeled biotinylation assay. The cardiac secretome function was analyzed by mass spectrometry. We reported that blood glucose concentration was lower in diabetic TG mice compared to diabetic WT mice (p=0.023). Cell surface GLUT-4 and -8 protein content was downregulated in the heart of WT diabetic vs. healthy mice (by 56% and 71%, p=0.01 and p<0.001, respectively), which was rescued in TG diabetic mice. In addition, diabetes induced a downregulation of cell surface GLUT4 trafficking in skeletal muscle, and white and brown adipose tissue of WT mice (by 79%, 68% and 74%, respectively, P<0.05), which was restored in TG diabetic mice. We further identified 28 and 32 candidate proteins that have a high probability (i.e., > 95%) of being secreted by the ventricle and atria of TG mice, respectively. Of these, 13 and 10 potentially secreted proteins by the atria and ventricle, respectively, were involved in metabolic processes.

In conclusion, these data suggest that cardiac-specific SERCA overexpression rescued hyperglycemia by improving glucose transport in insulin-sensitive tissues of diabetic TG mice. Insights gained from this study could identify the SERCA pump and its secreted proteins as novel pharmacological targets to regulate glucose homeostasis in diabetic patients.

Disclosure

Z. Maria: None. A. Campolo: None. S. Shoop Gray: None. S. Hartson: None. V. Lacombe: None.
Coadministration of GLP-1 and Y2R Receptor Agonists Synergize to Promote Muscle Glucose Uptake and Induce Diabetic Remission
Authors: BOLAND BRANDON , HOWARD VICTOR G. , BEATON MICHELLE , WILL SARAH , OLDHAM STEPHANIE , TREVASKIS JAMES , RHODES CHRISTOPHER J. , GRIMSBY JOE
Published: June 2018

One proposed mechanism for the effects of bariatric surgery is the enhanced postprandial release of enteroendocrine L-cell hormones, such as PYY and GLP-1. Four week co-administration of Fc-conjugated GLP-1R and Y2R-selective agonists induced weight loss, reduced %HbA1c, and improved glucose tolerance in DIO and KS db/db mice compared to vehicle or monotherapy control groups. To assess the impact of this combination on glucose control, a hyperinsulinemic/euglycemic clamp was performed in KS db/db mice following two week treatment with vehicle or co-administration of GLP-1/Y2R agonists. A vehicle-treated group weight-matched to combination-treated mice was also assessed. Compared to KS db/db vehicle animals, combination-treated mice exhibited a 16-fold greater glucose infusion rate compared to only 4-fold in weight-matched controls. Glucose uptake was increased 4-fold in the skeletal muscle of combination-treated animals, but was unaltered in adipose or brain. Weight-matched controls did not exhibit increased glucose uptake in any tissue. To better characerize the mechanism of Fc-GLP-1/Fc-Y2R action on peripheral glucose metabolism, lean mice were acutely administered Fc-GLP-1 and/or Fc-Y2R, and then sacrificed to assess brain c-Fos activation. Compared to monotherapies, combination administration led to additive c-Fos activation in hindbrain regions. Strikingly, whereas monotherapy had no effect on the PVH, combination administration led to a synergistic 2-fold increase in c-Fos immunoreactivity. These findings implicate a neuronal population in the PVH as a putative driver of the antidiabetic efficacy observed following co-administration of GLP-1R and Y2R selective peptides, and may represent a novel mechanism to improve insulin sensitivity and skeletal muscle glucose uptake.

Disclosure

B. Boland: Employee; Self; MedImmune. V.G. Howard: Employee; Self; AstraZeneca. Stock/Shareholder; Self; Regeneron Pharmaceuticals, Inc., AstraZeneca. M. Beaton: Employee; Self; MedImmune. Employee; Spouse/Partner; MedImmune. S. Will: Employee; Self; MedImmune. Stock/Shareholder; Self; AstraZeneca. S. Oldham: Stock/Shareholder; Self; AstraZeneca. Employee; Self; MedImmune. J. Trevaskis: Employee; Self; MedImmune. Stock/Shareholder; Self; AstraZeneca. C.J. Rhodes: Stock/Shareholder; Self; AstraZeneca. J. Grimsby: Employee; Self; AstraZeneca.
NFκB Regulation of Mitochondrial Function in Skeletal and Cardiac Muscle
Authors: VALENTINE JOE , LI MENGYAO E. , ZHANG NING , SHOELSON STEVEN E. , MUSI NICOLAS
Published: June 2018

NFκB is a transcription factor that controls immune and inflammatory processes. In muscle, NFκB has been implicated in regulation of muscle mass/function, metabolism, and mitochondrial function. Yet, NFκB’s role in aging-related changes to skeletal muscle and heart remains less defined. To investigate the role of NFκB in aging skeletal muscle and heart, we study a mouse model (MISR mice) with suppressed NFκB signaling in these tissues. Recently we found that these mice have exacerbated loss of skeletal muscle mass during aging. Here, we report that NFκB suppression caused reductions in skeletal muscle mass as early as 1 month of age. Aging per se (in WT mice) lead to a global downregulation of mitochondrial function (reduced respiration and enhanced reactive oxygen species production) and expression of mitochondrial biogenesis genes in skeletal muscle. Furthermore, suppression of NFκB signaling in skeletal muscle resulted in mitochondrial function defects in early life (4 months old), whereas in aged mice (30-33 months old) it had the opposite effect. Contrary to findings in skeletal muscle, in the heart aging increased mitochondrial respiration and reactive oxygen species production (in WT mice) and NFκB suppression protected against the aging related changes to reactive oxygen species production. We conclude that suppression of the canonical NFκB pathway has antagonistic pleiotropic effects (detrimental in early life and advantageous in aging animals) on mitochondrial function in skeletal muscle, but is beneficial throughout the lifespan in the heart. Furthermore, canonical NFκB signaling regulates muscle development and cellular metabolism at the transcriptional and functional levels.

Disclosure

J. Valentine: None. M.E. Li: None. N. Zhang: None. S.E. Shoelson: Consultant; Self; Par Pharmaceuticals. Stock/Shareholder; Self; Catabasis Pharmaceuticals. N. Musi: None.
Assessment of Proinflammatory Mediators of Beta-Cell Circadian Clock Dysfunction in Diabetes
Authors: JAVEED NAUREEN , RAKSHIT KUNTOL , MATVEYENKO ALEKSEY
Published: June 2018

Both type 1 and type 2 diabetes are characterized by a decline in β-cell function and mass partly attributed to exposure of β-cells to proinflammatory cytokines. The molecular mechanisms underlying this process are not well understood, however several lines of evidence have linked the circadian clock with regulation of the deleterious proinflammatory effects in diabetes. Therefore, in this study, we assessed the effect of known proinflammatory mediators of β-cell failure in diabetes (IL-1β, TNFα, IL-6, and IFNγ) on the β-cell circadian clock. Through real-time bioluminescence tracking of islets from Per2:luciferase (a key circadian clock gene reporter) knock-in mice, our data revealed that IL-1β (2 ng/ml) diminished β-cell circadian rhythmicity via impairment of the amplitude and the phase of oscillations (p<0.vs. vehicle). This was in contrast to TNFα, IL-6, and IFNγ, which showed either mild suppression or no effect on the β-cell clock. We next assessed the ability of proinflammatory cytokines to modulate Bmal1 and Clock (two main transcription factors in the circadian pathway) gene and protein expression. Interestingly, studies using INS-1 832/13 cells and cadaveric human islets revealed that IL-1β addition (0.2-5 ng/ml) for 24 h significantly reduced Bmal1 (but not Clock) at both the mRNA (∼40-50%, p<0.05) and protein (10-65%, p<0.05) level in a dose dependent manner. In contrast, other cytokines (IL-6, TNFα, and IFNγ) only modestly diminished Bmal1 expression after 24 h. In assessing a molecular link between IL-1β and the β-cell clock, Bmal1 promoter activity was determined using a BMAL1:luciferase expressing INS-1 832/13 stable-transfected cell line. Importantly, IL-1β (0.01-5 ng/ml) showed a dose dependent decrease in Bmal1 promoter activation (up to 90%). This body of work provides the first novel connection between diabetogenic inflammatory cytokines, specifically IL-1β, as the dominant mediator of β-cell clock dysfunction in diabetes.

Disclosure

N. Javeed: None. K. Rakshit: None. A. Matveyenko: None.