Glucagon-like peptide-1 (GLP-1) receptor agonists are a relatively new treatment option for obesity and type 2 diabetes. Treatment has been shown to result in in weight loss and improved glycemic... Show moreGlucagon-like peptide-1 (GLP-1) receptor agonists are a relatively new treatment option for obesity and type 2 diabetes. Treatment has been shown to result in in weight loss and improved glycemic control. In this thesis, the effects of treatment on the different adipose tissue depots and on cardiac function are described. In a randomised controlled trial, we treated patients with type 2 diabetes from South Asian descent, a population with increased risk to develop type 2 diabetes and cardiovascular disease compared to Western Europeans, with liraglutide, a GLP-1 receptor agonist, or placebo, and studied these subjects with MRI. We concluded that liraglutide and possibly other GLP-1 receptor agonists can be a good strategy to reduce the volume of visceral adipose tissue. This reduction was accompanied by a significant improvement of glycemic control. Lastly, we provided evidence that liraglutide does not improve cardiac function and myocardial tissue characteristics and thus does not improve diabetic cardiomyopathy. In addition, in another study, we studied the mechanism behind GLP-1 receptor agonism induced weight loss and concluded that liraglutide induces weight loss in humans by decreasing energy intake rather than by activating brown adipose tissue or increasing energy expenditure. Show less
Type 2 diabetes en hart- en vaatziekten (‘cardiometabole ziekten’) leiden wereldwijd tot veel sterfte. Vergeleken met mensen van West-Europese afkomst hebben Zuid-Aziaten een verhoogd risico op... Show moreType 2 diabetes en hart- en vaatziekten (‘cardiometabole ziekten’) leiden wereldwijd tot veel sterfte. Vergeleken met mensen van West-Europese afkomst hebben Zuid-Aziaten een verhoogd risico op deze ziekten. Dit komt gedeeltelijk door hun ongunstige lichaamssamenstelling met veel buikvet en vetopslag in organen zoals spieren en lever, wat hun werking verstoort. Het verminderen van overgewicht verlaagt het risico op type 2 diabetes en hart- en vaatziekten. Verminderen van voedselinname en verhogen van het energieverbruik kan hieraan bijdragen. Een veelbelovende aanpak om het energieverbruik te verhogen, is het stimuleren van vet- en suikerverbranding door lichaamseigen bruin vetweefsel. In dit proefschrift onderzochten wij eerst mechanismen die bijdragen aan cardiometabole ziekten in Zuid-Aziaten. Wij observeerden verminderde Wnt signaaltransductie in wit vet van Zuid-Aziaten, wat samenhing met minder insulinegevoeligheid in dit weefsel. Ook vonden wij een andere samenstelling van LDL-deeltjes in Zuid-Aziaten, wat samenhing met een verhoogde neiging van deze deeltjes om samen te klonteren. Daarna onderzochten wij de effectiviteit van geneesmiddelen om bruin vet activiteit te verhogen en de cardiometabole gezondheid te verbeteren. Wij lieten zien dat stimuleren van de beta-adrenerge receptor de stofwisseling verhoogt en vetverbranding door bruin vet stimuleert, echter niet méer dan koudeblootstelling. Ook vonden wij dat GLP-1 receptoragonisme de suikeropname door bruin vet stimuleert, wat mogelijk bijdraagt aan een gunstig effect op het lichaamsgewicht en suiker- en vetstofwisseling. Deze studies hebben bijgedragen aan kennis over risicofactoren voor cardiometabole ziekten en de ontwikkeling van nieuwe therapeutische strategieën om deze ziekten tegen te gaan, vooral in Zuid-Aziaten. Show less
Aims Data on the effect of liraglutide on glycemic endpoints in people with T2DM using multiple daily insulin injections (MDI) are scarce, especially in the context of ethnicity. Methods This is a... Show moreAims Data on the effect of liraglutide on glycemic endpoints in people with T2DM using multiple daily insulin injections (MDI) are scarce, especially in the context of ethnicity. Methods This is a secondary analysis of the placebo-controlled randomized clinical "MAGNA VICTORIA" trials in Western European (WE) and South Asian (SA) people with T2DM. Participants had inadequate glycemic control despite using metformin and/or sulfonylurea derivatives and/or insulin. Participants were assigned to liraglutide (1.8 mg) or placebo for 6 months, in addition to standard care. The primary endpoint number of participants reaching target HbA1c was compared for liraglutide versus placebo in the complete dataset and MDI-treated participants using Chi-square test. Liraglutide's efficacy in WE and SA was compared using a generalized linear model. Results Forty-five subjects were randomized to liraglutide and 51 to placebo. In each group, one participant did not complete the study. Liraglutide-treated patients reached target HbA1c more frequently: 23/45 (51%) vs 11/51 (22%), relative probability 2.4 (1.3-4.3), p = 0.002. Subgroup analysis in 43 MDI participants showed that the proportion reaching target HbA1c using liraglutide was significantly higher than in placebo: 9/22 (41%) vs 1/21 (5%), p = 0.005. There was no difference between WE and SA in terms of liraglutide efficacy (p = 0.18). Conclusions Liraglutide treatment resulted in increased chance of reaching target HbA1c as compared to placebo. Liraglutide efficacy was sustained in participants using MDI regimens and those of SA descent. Liraglutide should be considered for T2DM people with inadequate glycemic control despite MDI. Show less
Nahon, K.J.; Janssen, L.G.M.; Mishre, A.S.D.S.; Bilsen, M.P.; Eijk, J.A. van der; Botani, K.; ... ; Rensen, P.C.N. 2020
Aim To compare the effects of cold exposure and the beta 3-adrenergic receptor agonist mirabegron on plasma lipids, energy expenditure and brown adipose tissue (BAT) activity in South Asians versus... Show moreAim To compare the effects of cold exposure and the beta 3-adrenergic receptor agonist mirabegron on plasma lipids, energy expenditure and brown adipose tissue (BAT) activity in South Asians versus Europids. Materials and Methods Ten lean Dutch South Asian (aged 18-30 years; body mass index [BMI] 18-25 kg/m(2)) and 10 age- and BMI-matched Europid men participated in a randomized, double-blinded, cross-over study consisting of three interventions: short-term (similar to 2 hours) cold exposure, mirabegron (200 mg one dose p.o.) and placebo. Before and after each intervention, we performed lipidomic analysis in serum, assessed resting energy expenditure (REE) and skin temperature, and measured BAT fat fraction by magnetic resonance imaging. Results In both ethnicities, cold exposure increased the levels of several serum lipid species, whereas mirabegron only increased free fatty acids. Cold exposure increased lipid oxidation in both ethnicities, while mirabegron increased lipid oxidation in Europids only. Cold exposure and mirabegron enhanced supraclavicular skin temperature in both ethnicities. Cold exposure decreased BAT fat fraction in both ethnicities. After the combination of data from both ethnicities, mirabegron decreased BAT fat fraction compared with placebo. Conclusions In South Asians and Europids, cold exposure and mirabegron induced beneficial metabolic effects. When combining both ethnicities, cold exposure and mirabegron increased REE and lipid oxidation, coinciding with a higher supraclavicular skin temperature and lower BAT fat fraction. Show less
Background The pathogenesis and cardiovascular impact of type 2 diabetes (T2D) may be different in South Asians compared with other ethnic groups. The phenotypic characterization of diabetic... Show moreBackground The pathogenesis and cardiovascular impact of type 2 diabetes (T2D) may be different in South Asians compared with other ethnic groups. The phenotypic characterization of diabetic cardiomyopathy remains debated and little is known regarding differences in T2D-related cardiovascular remodeling across ethnicities. We aimed to characterize the differences in left ventricular (LV) diastolic and systolic function, LV structure, myocardial tissue characteristics and aortic stiffness between T2D patients and controls and to assess the differences in T2D-related cardiovascular remodeling between South Asians and Europeans. Methods T2D patients and controls of South Asian and European descent underwent 3 Tesla cardiovascular magnetic resonance imaging (CMR) and cardiac proton-magnetic resonance spectroscopy (H-1-MRS). Differences in cardiovascular parameters between T2D patients and controls were examined using ANCOVA and were reported as mean (95% CI). Ethnic group comparisons in the association of T2D with cardiovascular remodeling were made by adding the interaction term between ethnicity and diabetes status to the model. Results A total of 131 individuals were included (54 South Asians [50.1 +/- 8.7 years, 33% men, 33 patients vs. 21 controls) and 77 Europeans (58.8 +/- 7.0 years, 56% men, 48 patients vs. 29 controls)]. The ratio of the transmitral early and late peak filling rate (E/A) was lower in T2D patients compared with controls, in South Asians [- 0.20 (- 0.36; - 0.03), P = 0.021] and Europeans [- 0.20 (- 0.36; - 0.04), P = 0.017], whereas global longitudinal strain and aortic pulse wave velocity were similar. South Asian T2D patients had a higher LV mass [+ 22 g (15; 30), P < 0.001] (P for interaction by ethnicity = 0.005) with a lower extracellular volume fraction [- 1.9% (- 3.4; - 0.4), P = 0.013] (P for interaction = 0.114), whilst European T2D patients had a higher myocardial triglyceride content [+ 0.59% (0.35; 0.84), P = 0.001] (P for interaction = 0.002) than their control group. Conclusions Diabetic cardiomyopathy was characterized by impaired LV diastolic function in South Asians and Europeans. Increased LV mass was solely observed among South Asian T2D patients, whereas differences in myocardial triglyceride content between T2D patients and controls were only present in the European cohort. The diabetic cardiomyopathy phenotype may differ between subsets of T2D patients, for example across ethnicities, and tailored strategies for T2D management may be required. Show less
People of South Asian origin have an increased risk of developing type 2 diabetes (T2D) and cardiovascular disease (CVD) compared to people of Western European descent. Not only is the prevalence... Show morePeople of South Asian origin have an increased risk of developing type 2 diabetes (T2D) and cardiovascular disease (CVD) compared to people of Western European descent. Not only is the prevalence of these diseases higher in South Asians, they also occur at a younger age and lower BMI, and have a more severe course. The high prevalence of T2D and CVD in South Asians, who comprise one fifth of the total world__s population, poses a major health and socioeconomic burden worldwide. The underlying cause of this excess risk is, however, still poorly understood. The studies described in this thesis were performed to gain more insight in the pathogenesis of T2D and CVD in South Asians and to provide new leads for preventive strategies and treatment options. For this purpose sophisticated techniques were used such as hyperinsulinemic-euglycemic clamp with stable isotopes, indirect calorimetry, skeletal muscle biopsies, MRI and spectroscopy, and brown fat quantification using PET-CT-imaging, combined with short-term dietary interventions, in healthy lean young adult men and overweight adult men. These studies have led to a number of promising areas for further research. It seems that not one, but multiple metabolic mechanisms have been affected, most likely due to gene-environment interactions. Show less
Nicolaou, M.; Vlaar, E.; Valkengoed, I. van; Middelkoop, B.; Stronks, K.; Nierkens, V. 2014
This thesis focuses on the incidence and risk factors for nephropathy in diabetic and non-diabetic Surinamese South Asians. The Surinamese South Asians, originally descended from the North-East... Show moreThis thesis focuses on the incidence and risk factors for nephropathy in diabetic and non-diabetic Surinamese South Asians. The Surinamese South Asians, originally descended from the North-East India. Due to the former colonial bounds with the Netherlands, a relatively young South Asian migrant population settled in the Netherlands. South Asians have a high prevalence of central obesity and an eight-fold higher prevalence for type 2 diabetes mellitus. We found the following conclusions: 1.Surinamese South Asian persons have a nearly 40-fold higher risk for end-stage diabetic nephropathy in comparison to Dutch European persons. 2.There was no familial predisposition for diabetic nephropathy among South Asian families. 3.South Asian type 2 diabetic patients have a three-fold higher risk for diabetic nephropathy and faster progression of renal insufficiency in comparison to Dutch European patients. 4.Central obesity is an early and independent risk factor for increased albuminuria in normoglycemic South Asian subjects. We assume that the nearly 40-fold higher risk of end-stage diabetic nephropathy in South Asian migrants is primarily caused by central obesity which leads to: a. Early renal injury in the pre-diabetic state. b. Eight-times higher prevalence of type 2 diabetes mellitus. b. More diabetic nephropathy and faster decline in renal function. Show less