👤 Annika Thorsell

Alcohol use disorder (AUD) remains a major public health problem, with few effective medications currently available. However, peptides of the gut-brain axis appear to offer promising therapeutic targets for AUD as they influence the mesolimbic reward circuitry. Here, we examined the effects of tirzepatide, a long-acting dual glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) agonist approved for diabetes and obesity, using behavioural assays (locomotor activity and conditioned place preference), alcohol intake paradigms (intermittent access two-bottle choice, drinking in the dark and the alcohol deprivation effect), and molecular analyses (microdialysis, electrophysiology and proteomics) in rodents. First, tirzepatide effectively attenuated the rewarding properties of alcohol, measured through locomotor stimulation, conditioned place preference, and accumbal dopamine release (P < 0.001). Subsequently, this GLP-1R/GIPR agonist dose-dependently reduced voluntary alcohol consumption (P < 0.001), prevented binge (P < 0.01) and relapse-like drinking (P < 0.001), and maintained efficacy during repeated administration (P < 0.001). Finally, tirzepatide induced sustained synaptic depression in the lateral septum (P < 0.05) and further altered histone regulatory proteins in this region (P < 0.05), suggesting a potential neural substrate for its effects. Moreover, the GLP-1R/GIPR agonist affected metabolic parameters including body weight (P < 0.001), adipose tissue mass (P < 0.01), hepatic triglycerides (P < 0.01) and circulating pro-inflammatory cytokines (P < 0.05). Together, our findings suggest tirzepatide modulates alcohol-related behaviours through reward-related mechanisms while also affecting physiological consequences associated with long-term alcohol use. Given tirzepatide's established clinical use and the consistency of effects observed here, these results support further investigation for treating AUD and associated complications. The study is supported by grants from the Swedish Research Council (2023-2600, 2020-00559, 2020-01463, 2024-03054), LUA/ALF (723941 & 1005347) from the Sahlgrenska University Hospital, Alcohol Research Council of the Swedish Alcohol Retailing Monopoly (FO2024-0048), National Institutes of Health (NIH) (P50 AA010761 & U01 AA014095), U.S. Department of Veterans Affairs Office of Research and Development (BLR&D I01BX000813 & IK6BX006299), Herbert & Karin Jacobssons Foundation (2024-Forskning-225), Adlerbertska Research Foundation (2024-791), Wilhelm & Martina Lundgren's Research Foundation (2024-SA-4698), Åke Wibergs Foundation (M24-0216), Swedish Diabetes Foundation (DIA 2024-898) and Mary von Sydow Foundation (2024-36 & 2024-185). Thaynnam A Emous held an international internship scholarship from the São Paulo Research Foundation (FAPESP), Process Number #2023/18470-5, while conducting research at the University of Gothenburg. Show less

BackgroundApolipoprotein C-III (apoC-III) is a regulator of triglyceride (TG) metabolism, and due to its association with risk of cardiovascular disease, is an emergent target for pharmacological intervention. The impact of substantially lowering apoC-III on lipoprotein metabolism is not clear.MethodsWe investigated the kinetics of apolipoproteins B48 and B100 (apoB48 and apoB100) in chylomicrons, VLDL1, VLDL2, IDL, and LDL in patients heterozygous for a loss-of-function (LOF) mutation in the APOC3 gene. Studies were conducted in the postprandial state to provide a more comprehensive view of the influence of this protein on TG transport.ResultsCompared with non-LOF variant participants, a genetically determined decrease in apoC-III resulted in marked acceleration of lipolysis of TG-rich lipoproteins (TRLs), increased removal of VLDL remnants from the bloodstream, and substantial decrease in circulating levels of VLDL1, VLDL2, and IDL particles. Production rates for apoB48-containing chylomicrons and apoB100-containing VLDL1 and VLDL2 were not different between LOF carriers and noncarriers. Likewise, the rate of production of LDL was not affected by the lower apoC-III level, nor were the concentration and clearance rate of LDL-apoB100.ConclusionThese findings indicate that apoC-III lowering will have a marked effect on TRL and remnant metabolism, with possibly significant consequences for cardiovascular disease prevention.Trial registrationClinicalTrials.gov NCT04209816 and NCT01445730.FundingSwedish Heart-Lung Foundation, Swedish Research Council, ALF grant from the Sahlgrenska University Hospital, Novo Nordisk Foundation, Sigrid Juselius Foundation, Helsinki University Hospital Government Research funds, Finnish Heart Foundation, and Finnish Diabetes Research Foundation. Show less

To investigate how apolipoprotein C-III (apoC-III) metabolism is altered in subjects with type 2 diabetes, whether the perturbed plasma triglyceride concentrations in this condition are determined primarily by the secretion rate or the removal rate of apoC-III, and whether improvement of glycaemic control using the glucagon-like peptide-1 analogue liraglutide for 16 weeks modifies apoC-III dynamics. Postprandial apoC-III kinetics were assessed after a bolus injection of [5,5,5- Improved glycaemic control by liraglutide therapy for 16 weeks significantly reduced apoC-III secretion rate (561 ± 198 vs. 652 ± 196 mg/d, P = 0.03) and apoC-III levels (10.0 ± 3.8 vs. 11.7 ± 4.3 mg/dL, P = 0.035) in subjects with type 2 diabetes. Change in apoC-III secretion rate was significantly associated with the improvement in indices of glucose control (r = 0.67; P = 0.009) and change in triglyceride area under the curve (r = 0.59; P = 0.025). In line with this, the apoC-III secretion rate was higher in subjects with type 2 diabetes compared with BMI-matched non-diabetic subjects (676 ± 208 vs. 505 ± 174 mg/d, P = 0.042). The results reveal that the secretion rate of apoC-III is associated with elevation of triglyceride-rich lipoproteins in subjects with type 2 diabetes, potentially through the influence of glucose homeostasis on the production of apoC-III. Show less