Daniel F Vatner1, Leigh Goedeke2, Joao-Paulo G Camporez2, Kun Lyu3, Ali R Nasiri2, Dongyan Zhang4, Sanjay Bhanot5, Susan F Murray5, Christopher D Still6, Glenn S Gerhard6, Gerald I Shulman2,3,4, Varman T Samuel7,8. 1. Department of Internal Medicine, Yale University School of Medicine, P.O. Box 208020, New Haven, CT, 06520, USA. daniel.vatner@yale.edu. 2. Department of Internal Medicine, Yale University School of Medicine, P.O. Box 208020, New Haven, CT, 06520, USA. 3. Department of Cellular & Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06520, USA. 4. Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT, 06520, USA. 5. Ionis Pharmaceuticals, Carlsbad, CA, 92008, USA. 6. Obesity Institute, Geisinger Health System, Danville, PA, 17822, USA. 7. Department of Internal Medicine, Yale University School of Medicine, P.O. Box 208020, New Haven, CT, 06520, USA. varman.samuel@yale.edu. 8. Veterans Affairs Medical Center, 950 Campbell Ave, BLG 5 3rd floor, West Haven, CT, 06516, USA. varman.samuel@yale.edu.
Abstract
AIMS/HYPOTHESIS: Targeting regulators of adipose tissue lipoprotein lipase could enhance adipose lipid clearance, prevent ectopic lipid accumulation and consequently ameliorate insulin resistance and type 2 diabetes. Angiopoietin-like 8 (ANGPTL8) is an insulin-regulated lipoprotein lipase inhibitor strongly expressed in murine adipose tissue. However, Angptl8 knockout mice do not have improved insulin resistance. We hypothesised that pharmacological inhibition, using a second-generation antisense oligonucleotide (ASO) against Angptl8 in adult high-fat-fed rodents, would prevent ectopic lipid accumulation and insulin resistance by promoting adipose lipid uptake. METHODS: ANGPTL8 expression was assessed by quantitative PCR in omental adipose tissue of bariatric surgery patients. High-fat-fed Sprague Dawley rats and C57BL/6 mice were treated with ASO against Angptl8 and insulin sensitivity was assessed by hyperinsulinaemic-euglycaemic clamps in rats and glucose tolerance tests in mice. Factors mediating lipid-induced hepatic insulin resistance were assessed, including lipid content, protein kinase Cε (PKCε) activation and insulin-stimulated Akt phosphorylation. Rat adipose lipid uptake was assessed by mixed meal tolerance tests. Murine energy balance was assessed by indirect calorimetry. RESULTS: Omental fat ANGPTL8 mRNA expression is higher in obese individuals with fatty liver and insulin resistance compared with BMI-matched insulin-sensitive individuals. Angptl8 ASO prevented hepatic steatosis, PKCε activation and hepatic insulin resistance in high-fat-fed rats. Postprandial triacylglycerol uptake in white adipose tissue was increased in Angptl8 ASO-treated rats. Angptl8 ASO protected high-fat-fed mice from glucose intolerance. Although there was no change in net energy balance, Angptl8 ASO increased fat mass in high-fat-fed mice. CONCLUSIONS/ INTERPRETATION: Disinhibition of adipose tissue lipoprotein lipase is a novel therapeutic modality to enhance adipose lipid uptake and treat non-alcoholic fatty liver disease and insulin resistance. In line with this, adipose ANGPTL8 is a candidate therapeutic target for these conditions.
AIMS/HYPOTHESIS: Targeting regulators of adipose tissue lipoprotein lipase could enhance adipose lipid clearance, prevent ectopic lipid accumulation and consequently ameliorate insulin resistance and type 2 diabetes. Angiopoietin-like 8 (ANGPTL8) is an insulin-regulated lipoprotein lipase inhibitor strongly expressed in murine adipose tissue. However, Angptl8 knockout mice do not have improved insulin resistance. We hypothesised that pharmacological inhibition, using a second-generation antisense oligonucleotide (ASO) against Angptl8 in adult high-fat-fed rodents, would prevent ectopic lipid accumulation and insulin resistance by promoting adipose lipid uptake. METHODS:ANGPTL8 expression was assessed by quantitative PCR in omental adipose tissue of bariatric surgery patients. High-fat-fed Sprague Dawley rats and C57BL/6 mice were treated with ASO against Angptl8 and insulin sensitivity was assessed by hyperinsulinaemic-euglycaemic clamps in rats and glucose tolerance tests in mice. Factors mediating lipid-induced hepatic insulin resistance were assessed, including lipid content, protein kinase Cε (PKCε) activation and insulin-stimulated Akt phosphorylation. Rat adipose lipid uptake was assessed by mixed meal tolerance tests. Murine energy balance was assessed by indirect calorimetry. RESULTS: Omental fat ANGPTL8 mRNA expression is higher in obese individuals with fatty liver and insulin resistance compared with BMI-matched insulin-sensitive individuals. Angptl8ASO prevented hepatic steatosis, PKCε activation and hepatic insulin resistance in high-fat-fed rats. Postprandial triacylglycerol uptake in white adipose tissue was increased in Angptl8ASO-treated rats. Angptl8ASO protected high-fat-fed mice from glucose intolerance. Although there was no change in net energy balance, Angptl8ASO increased fat mass in high-fat-fed mice. CONCLUSIONS/ INTERPRETATION: Disinhibition of adipose tissue lipoprotein lipase is a novel therapeutic modality to enhance adipose lipid uptake and treat non-alcoholic fatty liver disease and insulin resistance. In line with this, adipose ANGPTL8 is a candidate therapeutic target for these conditions.
Authors: Marissa Lightbourne; Anna Wolska; Brent S Abel; Kristina I Rother; Mary Walter; Yevgeniya Kushchayeva; Sungyoung Auh; Robert D Shamburek; Alan T Remaley; Ranganath Muniyappa; Rebecca J Brown Journal: J Endocr Soc Date: 2020-12-04
Authors: C Mele; A Crinò; D Fintini; S Mai; A Convertino; S Bocchini; P Di Paolo; G Grugni; G Aimaretti; M Scacchi; P Marzullo Journal: J Endocrinol Invest Date: 2020-10-16 Impact factor: 4.256