| 1. |
- Agudelo, Leandro Z., et al.
(författare)
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Metabolic resilience is encoded in genome plasticity
- 2021
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Metabolism plays a central role in evolution, as resource conservation is a selective pressure for fitness and survival.Resource-driven adaptations offer a good model to study evolutionary innovation more broadly. It remains unknown howresource-driven optimization of genome function integrates chromatin architecture with transcriptional phase transitions.Here we show that tuning of genome architecture and heterotypic transcriptional condensates mediate resilience tonutrient limitation. Network genomic integration of phenotypic, structural, and functional relationships reveals that fattissue promotes organismal adaptations through metabolic acceleration chromatin domains and heterotypic PGC1Acondensates. We find evolutionary adaptations in several dimensions; low conservation of amino acid residues withinprotein disorder regions, nonrandom chromatin location of metabolic acceleration domains, condensate-chromatin stabilitythrough cis-regulatory anchoring and encoding of genome plasticity in radial chromatin organization. We show thatenvironmental tuning of these adaptations leads to fasting endurance, through efficient nuclear compartmentalization oflipid metabolic regions, and, locally, human-specific burst kinetics of lipid cycling genes. This process reduces oxidativestress, and fatty-acid mediated cellular acidification, enabling endurance of condensate chromatin conformations.Comparative genomics of genetic and diet perturbations reveal mammalian convergence of phenotype and structuralrelationships, along with loss of transcriptional control by diet-induced obesity. Further, we find that radial transcriptionalorganization is encoded in functional divergence of metabolic disease variant-hubs, heterotypic condensate composition,and protein residues sensing metabolic variation. During fuel restriction, these features license the formation of largeheterotypic condensates that buffer proton excess, and shift viscoelasticity for condensate endurance. This mechanismmaintains physiological pH, reduces pH-resilient inflammatory gene programs, and enables genome plasticity throughtranscriptionally driven cell-specific chromatin contacts. In vivo manipulation of this circuit promotes fasting-likeadaptations with heterotypic nuclear compartments, metabolic and cell-specific homeostasis. In sum, we uncover here ageneral principle by which transcription uses environmental fluctuations for genome function, and demonstrate howresource conservation optimizes transcriptional self-organization through robust feedback integrators, highlighting obesityas an inhibitor of genome plasticity relevant for many diseases.
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| 2. |
- Atabaki-Pasdar, Naeimeh, et al.
(författare)
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Inferring causal pathways between metabolic processes and liver fat accumulation: an IMI DIRECT study
- 2021
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD) often co-occur. Defining causal pathways underlying this relationship may help optimize the prevention and treatment of both diseases. Thus, we assessed the strength and magnitude of the putative causal pathways linking dysglycemia and fatty liver, using a combination of causal inference methods.Measures of glycemia, insulin dynamics, magnetic resonance imaging (MRI)-derived abdominal and liver fat content, serological biomarkers, lifestyle, and anthropometry were obtained in participants from the IMI DIRECT cohorts (n=795 with new onset T2D and 2234 individuals free from diabetes). UK Biobank (n=3641) was used for modelling and replication purposes. Bayesian networks were employed to infer causal pathways, with causal validation using two-sample Mendelian randomization.Bayesian networks fitted to IMI DIRECT data identified higher basal insulin secretion rate (BasalISR) and MRI-derived excess visceral fat (VAT) accumulation as the features of dysmetabolism most likely to cause liver fat accumulation; the unconditional probability of fatty liver (>5%) increased significantly when conditioning on high levels of BasalISR and VAT (by 23%, 32% respectively; 40% for both). Analyses in UK Biobank yielded comparable results. MR confirmed most causal pathways predicted by the Bayesian networks.Here, BasalISR had the highest causal effect on fatty liver predisposition, providing mechanistic evidence underpinning the established association of NAFLD and T2D. BasalISR may represent a pragmatic biomarker for NAFLD prediction in clinical practice.Competing Interest StatementHR is an employee and shareholder of Sanofi. MIM: The views expressed in this article are those of the author(s) and not necessarily those of the NHS, the NIHR, or the Department of Health. MIM has served on advisory panels for Pfizer, NovoNordisk and Zoe Global, has received honoraria from Merck, Pfizer, Novo Nordisk and Eli Lilly, and research funding from Abbvie, Astra Zeneca, Boehringer Ingelheim, Eli Lilly, Janssen, Merck, NovoNordisk, Pfizer, Roche, Sanofi Aventis, Servier, and Takeda. As of June 2019, MIM is an employee of Genentech, and a holder of Roche stock. AM is a consultant for Lilly and has received research grants from several diabetes drug companies. PWF has received research grants from numerous diabetes drug companies and fess as consultant from Novo Nordisk, Lilly, and Zoe Global Ltd. He is currently the Scientific Director in Patient Care at the Novo Nordisk Foundation. Other authors declare non competing interests.Funding StatementThe work leading to this publication has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement 115317 (DIRECT) resources of which are composed of financial contribution from the European Union Seventh Framework Programme (FP7/2007-2013) and EFPIA companies in kind contribution. NAP is supported in part by Henning och Johan Throne-Holsts Foundation, Hans Werthen Foundation, an IRC award from the Swedish Foundation for Strategic Research and a European Research Council award ERC-2015-CoG - 681742_NASCENT. HPM is supported by an IRC award from the Swedish Foundation for Strategic Research and a European Research Council award ERC-2015-CoG - 681742_NASCENT. AGJ is supported by an NIHR Clinician Scientist award (17/0005624). RK is funded by the Novo Nordisk Foundation (NNF18OC0031650) as part of a postdoctoral fellowship, an IRC award from the Swedish Foundation for Strategic Research and a European Research Council award ERC-2015-CoG - 681742_NASCENT. AK, PM, HF, JF and GNG are supported by an IRC award from the Swedish Foundation for Strategic Research and a European Research Council award ERC-2015-CoG - 681742_NASCENT. TJM is funded by an NIHR clinical senior lecturer fellowship. S.Bru acknowledges support from the Novo Nordisk Foundation (grants NNF17OC0027594 and NNF14CC0001). ATH is a Wellcome Trust Senior Investigator and is also supported by the NIHR Exeter Clinical Research Facility. JMS acknowledges support from Science for Life Laboratory (Plasma Profiling Facility), Knut and Alice Wallenberg Foundation (Human Protein Atlas) and Erling-Persson Foundation (KTH Centre for Precision Medicine). MIM is supported by the following grants; Wellcome (090532, 098381, 106130, 203141, 212259); NIH (U01-DK105535). PWF is supported by an IRC award from the Swedish Foundation for Strategic Research and a European Research Council award ERC-2015-CoG - 681742_NASCENT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:Approval for the study protocol was obtained from each of the regional research ethics review boards separately (Lund, Sweden: 20130312105459927, Copenhagen, Denmark: H-1-2012-166 and H-1-2012-100, Amsterdam, Netherlands: NL40099.029.12, Newcastle, Dundee and Exeter, UK: 12/NE/0132), and all participants provided written informed consent at enrolment. The research conformed to the ethical principles for medical research involving human participants outlined in the Declaration of Helsinki.All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesAuthors agree to make data and materials supporting the results or analyses presented in their paper available upon reasonable request
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| 3. |
- Bennet, Louise, et al.
(författare)
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Dubbelt så hög risk för diabetes typ 2 hos svenskar födda i Irak
- 2015
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Ingår i: Läkartidningen. - 0023-7205. ; 112:16, s. 1-4
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The MEDIM study reports that Immigrants from the Middle East to Sweden – independently of other diabetes related risk factors – have a twice as high type 2 diabetes risk as compared to non-immigrated Swedes. Diabetes onset occurs 6 years earlier in this group and is partly explained by family history and/or obesity. But the MEDIM study has identified that Middle Eastern background per se is an independent risk factor for earlier disease onset. Immigrants from the Middle East free of diabetes have a more pronounced insulin resistance and worse glycaemic control than non-immigrated Swedes independently of age, obesity or other risk factors for diabetes. To be able to reduce the risk of diabetes and offer an equal health care, glucose/HbA1c should be controlled on wide indications, and risk evaluation and preventive actions provided earlier for this population at high risk for type 2 diabetes. © 2015, Swedish Medical Association. All rights reserved.
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| 5. |
- Brito, Ema C, 1961-
(författare)
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Gene x lifestyle interactions in type 2 diabetes mellitus and related traits
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Type 2 diabetes is thought to result from interactions between genetic and lifestyle factors, but few robust examples exist. The overarching aim of this thesis was to discover such interactions by studying cohorts of white youth and adults from northern Europe in which physical activity, genotypes, and diabetes-related traits or diabetes incidence had been ascertained. Methods: The thesis includes four papers. In Paper I, we investigated associations and interactions between 35 common PPARGC1A polymorphisms and cardiovascular and metabolic disease traits in 2,101 Danish and Estonian children from the European Youth Heart Study (EYHS). Paper II used the same cohort to test associations and interactions on cardiometabolic traits for the diabetes-predisposing TCF7L2 polymorphism. In Paper III, we assessed associations for 17 type 2 diabetes gene polymorphisms on impaired glucose regulation (IGR) or incident type 2 diabetes, and tested whether these effects are modified by physical activity in a prospective cohort study of ~16,000 initially non-diabetic Swedish adults – the Malmö Preventive Project (MPP). Paper IV aimed to replicate main genetic effects and gene x physical activity interactions for an FTO polymorphism on obesity in 18,435 primarily non-diabetic Swedish (MPP) and Finnish (Prevalence, Prediction and Prevention of Diabetes in Botnia) adults. Results: In Paper I, nominally significant associations were observed for BMI (rs10018239, P=0.039), waist circumference (rs7656250, P=0.012; rs8192678 [Gly482Ser], P=0.015; rs3755863, P=0.02; rs10018239, P=0.043), systolic blood pressure (rs2970869, P=0.018) and fasting glucose concentrations (rs11724368, P=0.045). Stronger associations were observed for aerobic fitness (rs7656250, P=0.005; rs13117172, P=0.008) and fasting glucose concentrations (rs7657071, P=0.002). None remained significant after correcting for multiple statistical comparisons. We proceeded by testing for gene × physical activity interactions for the polymorphisms that showed statistical evidence of association (P<0.05) in the main effect models, but none was statistically significant. In Paper II, the minor T allele at the rs7903146 variant was associated with higher glucose levels in older (beta=–0.098 mmol/l per minor allele copy, P=0.029) but not in younger children (beta=–0.001 mmol/l per minor allele copy, P=0.972). A significant inverse association between the minor allele at rs7903146 and height was evident in boys (beta=–1.073 cm per minor allele copy, P=0.001), but not in girls. The test of interaction between the TCF7L2 rs7903146 variant and physical activity on HOMA-B was nominally statistically significant (beta=0.022, Pinteraction=0.015), whereby physical activity reduced the effect of the risk allele on estimated beta-cell function. In Paper III, tests of gene x physical activity interactions on IGR-risk for three polymorphisms were nominally statistically significant: CDKN2A/B rs10811661 (Pinteraction=0.015); HNF1B rs4430796 (Pinteraction=0.026); PPARG rs1801282 (Pinteraction=0.04). Consistent interactions were observed for the CDKN2A/B (Pinteraction=0.013) and HNF1B (Pinteraction=0.0009) variants on 2 hr glucose concentrations. Where type 2 diabetes was the outcome, only one statistically significant interaction effect was observed and this was for the HNF1B rs4430796 variant (Pinteraction=0.0004). The interaction effects for HNF1B on 2 hr glucose and incident diabetes remained significant after correction for multiple testing (Pinteraction=0.015 and 0.0068, respectively). In Paper IV, the minor A allele at rs9939609 was associated with higher BMI (P<0.0001). The tests of gene x physical activity interaction on BMI were not statistically significant in either cohort (Sweden: P=0.71, Finland: P=0.18). Conclusions: Variation at PPARGC1A is unlikely to have a major impact on cardiometabolic health in European children, but physical activity may modify the effect of the TFC7L2 variants on beta-cell function in this cohort. In Swedish adults, physical activity modifies the effects of common HNF1B and CDKN2A/B variants on risk of IGR and also modifies the effect of the HNF1B on type 2 diabetes risk. In Swedish and Finnish adults, we were unable to confirm previous reports of an interaction between FTO gene variation and physical activity on obesity predisposition.
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| 6. |
- Chikowore, Tinashe, et al.
(författare)
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GWAS transethnic meta-analysis of BMI in similar to 700k individuals reveals novel gene-smoking interaction in African populations
- 2020
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Ingår i: Genetic Epidemiology. - : John Wiley & Sons. - 0741-0395 .- 1098-2272. ; 44:5, s. 475-476
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Sixty two percent of the 1.12 billion obese people globally reside in low‐middle income countries, 77% of which are in Africa. There is paucity of data on gene‐lifestyle interactions associated with the increasing prevalence of obesity among Africans. We hypothesised that gene‐environment interacting (GEI) variants exhibit heterogenous effects on obesity in transethnic meta‐analysis of marginal SNP associations as a result of modification by an unknown exposure that varies across populations.Body mass index (BMI) genome‐wide association study (GWAS) summary statistics for 678,671 individuals representative of the major global ancestries were aggregated at 21,338,816 SNPs via fixed‐effects meta‐analysis. Lead SNPs attaining genome‐wide significance (P < 5 × 10−8) were tested for heterogeneity in effects between GWAS. Lead SNPs with significant evidence of heterogeneity after Bonferroni correction were then selected for interaction analysis with selected lifestyle factors in an independent AWI‐Gen study of 10,500 African participants. Significant interaction findings were then replicated in 3,177 individuals of African ancestry in the UK Biobank.Of 881 lead SNPs, five had significant heterogenous effects on BMI (P < 5.7 × 10−5). Rs471094, at the CDKAL1 locus had significant interaction with smoking status, which reduced the effect of the BMI raising allele in current smokers (Betaint = −0.949 kg/m2; P int = .002) compared with non‐smokers in AWI‐Gen. This finding was validated in the UK Biobank (Betaint = −1.471 kg/m2, P int = .020; meta‐analysis Betaint = −1.050 kg/m2, P int = .0002). Our results highlight the first gene‐lifestyle interaction on BMI in Africans and demonstrate the utility of transethnic meta‐analysis of GWAS for identifying GEI effects.
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| 7. |
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| 8. |
- Franks, Paul, et al.
(författare)
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Epigenetics and obesity: the devil is in the details
- 2010
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Ingår i: BMC Medicine. - : Springer Science and Business Media LLC. - 1741-7015. ; 8
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Obesity is a complex disease with multiple well-defined risk factors. Nevertheless, susceptibility to obesity and its sequelae within obesogenic environments varies greatly from one person to the next, suggesting a role for gene x environment interactions in the etiology of the disorder. Epigenetic regulation of the human genome provides a putative mechanism by which specific environmental exposures convey risk for obesity and other human diseases and is one possible mechanism that underlies the gene x environment/treatment interactions observed in epidemiological studies and clinical trials. A study published in BMC Medicine this month by Wang et al. reports on an examination of DNA methylation in peripheral blood leukocytes of lean and obese adolescents, comparing methylation patterns between the two groups. The authors identified two genes that were differentially methylated, both of which have roles in immune function. Here we overview the findings from this study in the context of those emerging from other recent genetic and epigenetic studies, discuss the strengths and weaknesses of the study and speculate on the future of epigenetics in chronic disease research. See research article: http://www.biomedcentral.com/1741-7015/8/87/abstract
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