| 1. |
- de Mello, Vanessa D., et al.
(författare)
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Indolepropionic acid and novel lipid metabolites are associated with a lower risk of type 2 diabetes in the Finnish Diabetes Prevention Study
- 2017
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Wide-scale profiling technologies including metabolomics broaden the possibility of novel discoveries related to the pathogenesis of type 2 diabetes (T2D). By applying non-targeted metabolomics approach, we investigated here whether serum metabolite profile predicts T2D in a well-characterized study population with impaired glucose tolerance by examining two groups of individuals who took part in the Finnish Diabetes Prevention Study (DPS); those who either early developed T2D (n = 96) or did not convert to T2D within the 15-year follow-up (n = 104). Several novel metabolites were associated with lower likelihood of developing T2D, including indole and lipid related metabolites. Higher indolepropionic acid was associated with reduced likelihood of T2D in the DPS. Interestingly, in those who remained free of T2D, indolepropionic acid and various lipid species were associated with better insulin secretion and sensitivity, respectively. Furthermore, these metabolites were negatively correlated with low-grade inflammation. We replicated the association between indolepropionic acid and T2D risk in one Finnish and one Swedish population. We suggest that indolepropionic acid, a gut microbiota-produced metabolite, is a potential biomarker for the development of T2D that may mediate its protective effect by preservation of alpha-cell function. Novel lipid metabolites associated with T2D may exert their effects partly through enhancing insulin sensitivity.
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| 2. |
- Kolehmainen, Marjukka, et al.
(författare)
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Healthy Nordic diet downregulates the expression of genes involved in inflammation in subcutaneous adipose tissue in individuals with features of the metabolic syndrome.
- 2015
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 101:1, s. 228-239
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Previously, a healthy Nordic diet (ND) has been shown to have beneficial health effects close to those of Mediterranean diets.OBJECTIVE: The objective was to explore whether the ND has an impact on gene expression in abdominal subcutaneous adipose tissue (SAT) and whether changes in gene expression are associated with clinical and biochemical effects.DESIGN: Obese adults with features of the metabolic syndrome underwent an 18- to 24-wk randomized intervention study comparing the ND with the control diet (CD) (the SYSDIET study, carried out within Nordic Centre of Excellence of the Systems Biology in Controlled Dietary Interventions and Cohort Studies). The present study included participants from 3 Nordic SYSDIET centers [Kuopio (n = 20), Lund (n = 18), and Oulu (n = 18)] with a maximum weight change of ±4 kg, highly sensitive C-reactive protein concentration <10 mg/L at the beginning and the end of the intervention, and baseline body mass index (in kg/m(2)) <38. SAT biopsy specimens were obtained before and after the intervention and subjected to global transcriptome analysis with Gene 1.1 ST Arrays (Affymetrix).RESULTS: Altogether, 128 genes were differentially expressed in SAT between the ND and CD (nominal P < 0.01; false discovery rate, 25%). These genes were overrepresented in pathways related to immune response (adjusted P = 0.0076), resulting mainly from slightly decreased expression in the ND and increased expression in the CD. Immune-related pathways included leukocyte trafficking and macrophage recruitment (e.g., interferon regulatory factor 1, CD97), adaptive immune response (interleukin32, interleukin 6 receptor), and reactive oxygen species (neutrophil cytosolic factor 1). Interestingly, the regulatory region of the 128 genes was overrepresented for binding sites for the nuclear transcription factor κB.CONCLUSION: A healthy Nordic diet reduces inflammatory gene expression in SAT compared with a control diet independently of body weight change in individuals with features of the metabolic syndrome. The study was registered at clinicaltrials.gov as NCT00992641.
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| 3. |
- Meijnikman, A. S., et al.
(författare)
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Hyperinsulinemia Is Highly Associated With Markers of Hepatocytic Senescence in Two Independent Cohorts
- 2022
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 71:9, s. 1929-1936
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Tidskriftsartikel (refereegranskat)abstract
- Cellular senescence is an essentially irreversible growth arrest that occurs in response to various cellular stressors and may contribute to development of type 2 diabetes mellitus and nonalcoholic fatty liver disease (NAFLD). In this article, we investigated whether chronically elevated insulin levels are associated with cellular senescence in the human liver. In 107 individuals undergoing bariatric surgery, hepatic senescence markers were assessed by immunohistochemistry as well as transcriptomics. A subset of 180 participants from the ongoing Finnish Kuopio OBesity Surgery (KOBS) study was used as validation cohort. We found plasma insulin to be highly associated with various markers of cellular senescence in liver tissue. The liver transcriptome of individuals with high insulin revealed significant upregulation of several genes associated with senescence: p21, TGFβ, PI3K, HLA-G, IL8, p38, Ras, and E2F. Insulin associated with hepatic senescence independently of NAFLD and plasma glucose. By using transcriptomic data from the KOBS study, we could validate the association of insulin with p21 in the liver. Our results support a potential role for hyperinsulinemia in induction of cellular senescence in the liver. These findings suggest possible benefits of lowering insulin levels in obese individuals with insulin resistance.
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| 4. |
- Cardona, Alexia, et al.
(författare)
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Epigenome-wide association study of incident type 2 diabetes in a British population : EPIC-Norfolk study
- 2019
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 68:12, s. 2315-2326
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Tidskriftsartikel (refereegranskat)abstract
- Epigenetic changes may contribute substantially to risks of diseases of aging. Previous studies reported seven methylation variable positions (MVPs) robustly associated with incident type 2 diabetes mellitus (T2DM). However, their causal roles in T2DM are unclear. In an incident T2DM case-cohort study nested within the populationbased European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort, we used whole blood DNA collected at baseline, up to 11 years before T2DM onset, to investigate the role of methylation in the etiology of T2DM. We identified 15 novel MVPs with robust associations with incident T2DM and robustly confirmed three MVPs identified previously (near to TXNIP, ABCG1, and SREBF1). All 18 MVPs showed directionally consistent associations with incident and prevalent T2DM in independent studies. Further conditional analyses suggested that the identified epigenetic signals appear related to T2DM via glucose and obesityrelated pathways acting before the collection of baseline samples.We integrated genome-wide genetic data to identify methylation-associated quantitative trait loci robustly associated with 16 of the 18 MVPs and found one MVP, cg00574958 at CPT1A, with a possible direct causal role in T2DM. None of the implicated genes were previously highlighted by genetic association studies, suggesting that DNA methylation studies may reveal novel biological mechanisms involved in tissue responses to glycemia.
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| 5. |
- de Mello, Vanessa, et al.
(författare)
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Human liver epigenetic alterations in non-alcoholic steatohepatitis are related to insulin action
- 2017
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Ingår i: Epigenetics. - : Informa UK Limited. - 1559-2294 .- 1559-2308. ; 12:4, s. 287-295
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Tidskriftsartikel (refereegranskat)abstract
- Both genetic and lifestyle factors contribute to the risk of non-alcoholic steatohepatitis (NASH). Additionally, epigenetic modifications may also play a key role in the pathogenesis of NASH. We therefore investigated liver DNA methylation, as a marker for epigenetic alterations, in individuals with simple steatosis and NASH, and further tested if these alterations were associated with clinical phenotypes. Liver biopsies obtained from 95 obese individuals (age: 49.5 ± 7.7 years, BMI: 43 ± 5.7 kg/m2, type 2 diabetes [T2D]: 35) as a wedge biopsy during a Roux-en-Y gastric bypass operation were investigated. Thirty-four individuals had a normal liver phenotype, 35 had simple steatosis, and 26 had NASH. Genome-wide DNA methylation pattern was analyzed using the Infinium HumanMethylation450 BeadChip. mRNA expression was analyzed from 42 individuals using the HumanHT-12 Expression BeadChip. We identified 1,292 CpG sites representing 677 unique genes differentially methylated in liver of individuals with NASH (q < 0.001), independently of T2D, age, sex, and BMI. Focusing on the top-ranking 30 and another 37 CpG sites mapped to genes enriched in pathways of metabolism (q = 0.0036) and cancer (q = 0.0001) all together, 59 NASH-associated CpG sites correlated with fasting insulin levels independently of age, fasting glucose, or T2D. From these, we identified 30 correlations between DNA methylation and mRNA expression, for example LDHB (r = −0.45, P = 0.003). We demonstrated that NASH, more than simple steatosis, associates with differential DNA methylation in the human liver. These epigenetic alterations in NASH are linked with insulin metabolism.
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| 6. |
- García-Calzón, Sonia, et al.
(författare)
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Sex Differences in the Methylome and Transcriptome of the Human Liver and Circulating HDL-Cholesterol Levels
- 2018
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 103:12, s. 4395-4408
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Tidskriftsartikel (refereegranskat)abstract
- Context: Epigenetics may contribute to sex-specific differences in human liver metabolism. Objective: To study the impact of sex on DNA methylation and gene expression in human liver. Design/Setting: Cross-sectional, Kuopio Obesity Surgery Study. Participants/Intervention: We analyzed DNA methylation with the Infinium HumanMethylation450 BeadChip in liver of an obese population (34 males, 61 females). Females had a higher high-density lipoprotein (HDL)-cholesterol levels compared with males. Gene expression was measured with the HumanHT-12 Expression BeadChip in a subset of 42 participants. Results: Females displayed higher average methylation in the X-chromosome, whereas males presented higher methylation in autosomes. We found 9455 CpG sites in the X-chromosome and 33,205 sites in autosomes with significant methylation differences in liver between sexes (q < 0.05). When comparing our findings with published studies, 95% of the sex-specific differences in liver methylation in the X-chromosome were also found in pancreatic islets and brain, and 26 autosomal sites showed sex-specific methylation differences in the liver as well as in other human tissues. Furthermore, this sex-specific methylation profile in liver was associated with hepatic gene expression changes between males and females. Notably, females showed higher HDL-cholesterol levels, which were associated with higher KDM6A expression and epigenetic differences in human liver. Accordingly, silencing of KDM6A in cultured liver cells reduced HDL-cholesterol levels and APOA1 expression, which is a major component of HDL particles. Conclusions: Human liver has a sex-specific methylation profile in both the X-chromosome and autosomes, which associates with hepatic gene expression changes and HDL-cholesterol. We identified KDM6A as a novel target that regulates HDL-cholesterol levels.
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| 7. |
- Mancina, Rosellina Margherita, et al.
(författare)
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The MBOAT7-TMC4 Variant rs641738 Increases Risk of Nonalcoholic Fatty Liver Disease in Individuals of European Descent.
- 2016
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Ingår i: Gastroenterology. - : Elsevier BV. - 1528-0012 .- 0016-5085. ; 150:5, s. 1219-1230
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Tidskriftsartikel (refereegranskat)abstract
- Nonalcoholic fatty liver disease (NAFLD) is a leading cause of liver damage and is characterized by steatosis. Genetic factors increase risk for progressive NAFLD. A genome-wide association study showed that the rs641738 C>T variant in the locus that contains the membrane bound O-acyltransferase domain-containing 7 gene (MBOAT7, also called LPIAT1) and transmembrane channel-like 4 gene (TMC4) increased the risk for cirrhosis in alcohol abusers. We investigated whether the MBOAT7-TMC4 is a susceptibility locus for the development and progression of NAFLD.
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| 8. |
- Meuronen, Topi, et al.
(författare)
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FADS1 rs174550 genotype and high linoleic acid diet modify plasma PUFA phospholipids in a dietary intervention study
- 2022
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Ingår i: European Journal of Nutrition. - : Springer Science and Business Media LLC. - 1436-6207 .- 1436-6215. ; 61:2, s. 1109-1120
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Fatty acid desaturase 1 (FADS1) gene encodes for delta-5 desaturase enzyme which is needed in conversion of linoleic acid (LA) to arachidonic acid (AA). Recent studies have shown that response to dietary PUFAs differs between the genotypes in circulating fatty acids. However, interactions between the FADS1 genotype and dietary LA on overall metabolism have not been studied. Objectives: We aimed to examine the interactions of FADS1 rs174550 genotypes (TT and CC) and high-LA diet to identify plasma metabolites that respond differentially to dietary LA according to the FADS1 genotype. Methods: A total of 59 men (TT n = 26, CC n = 33) consumed a sunflower oil supplemented diet for 4 weeks. Daily dose of 30, 40, or 50 ml was calculated based on body mass index. It resulted in 17–28 g of LA on top of the usual daily intake. Fasting plasma samples at the beginning and at the end of the intervention were analyzed with LC–MS/MS non-targeted metabolomics method. Results: At the baseline, the carriers of FADS1 rs174550-TT genotype had higher abundance of long-chain PUFA phospholipids compared to the FADS1 rs174550-CC one. In response to the high-LA diet, LA phospholipids and long-chain acylcarnitines increased and lysophospholipids decreased in fasting plasma similarly in both genotypes. LysoPE (20:4), LysoPC (20:4), and PC (16:0_20:4) decreased and cortisol increased in the carriers of rs174550-CC genotype; however, these genotype–diet interactions were not significant after correction for multiple testing. Conclusion: Our findings show that both FADS1 rs174550 genotype and high-LA diet modify plasma phospholipid composition. Trial registration: The study was registered to ClinicalTrials: NCT02543216, September 7, 2015 (retrospectively registered).
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| 9. |
- Oveis, Jamialahmadi, et al.
(författare)
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Exome-wide Association Study on Alanine Aminotransferase Identifies Sequence Variants in the GPAM and APOE Associated with Fatty Liver Disease.
- 2021
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Ingår i: Gastroenterology. - : Elsevier BV. - 1528-0012 .- 0016-5085. ; 160:5
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Tidskriftsartikel (refereegranskat)abstract
- Fatty liver disease (FLD) is a growing epidemic that is expected to be the leading cause of end-stage liver disease within the next decade. Both environmental and genetic factors contribute to the susceptibility of FLD. Several genetic variants contributing to FLD have been identified in exome-wide association studies. However, there is still a missing hereditability indicating that other genetic variants are yet to be discovered.To find genes involved in FLD, we first examined the association of missense and nonsense variants with alanine aminotransferase (ALT) at an exome-wide level in 425,671 participants from the UK Biobank. We then validated genetic variants with liver fat content in 8,930 participants in whom liver fat measurement was available, and replicated two genetic variants in three independent cohorts comprising 2,621 individuals with available liver biopsy.We identified 190 genetic variants independently associated with ALT after correcting for multiple testing with Bonferroni method. The majority of these variants were not previously associated with this trait. Among those associated, there was a striking enrichment of genetic variants influencing lipid metabolism. We identified the variants rs2792751 in GPAM/GPAT1, the gene encoding glycerol-3-phosphate acyltransferase, mitochondrial, and rs429358 in APOE, the gene encoding apolipoprotein E, as robustly associated with liver fat content and liver disease after adjusting for multiple testing. Both genes affect lipid metabolism in the liver.We identified two novel genetic variants in GPAM and APOE that are robustly associated with steatosis and liver damage. These findings may help to better elucidate the genetic susceptibility to FLD onset and progression.
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| 10. |
- Rantala, Eeva, et al.
(författare)
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Acceptability of workplace choice architecture modification for healthy behaviours
- 2023
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Ingår i: BMC Public Health. - : BioMed Central (BMC). - 1471-2458. ; 23:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Altering the choice architecture of decision contexts can assist behaviour change, but the acceptability of this approach has sparked debate. Considering hypothetical interventions, people generally welcome the approach for promoting health, but little evidence exists on acceptance in the real world. Furthermore, research has yet to explore the implementers’ perspective, acknowledging the multidimensionality of the acceptability construct. Addressing these knowledge gaps, this study evaluated the acceptability of a quasi-experimental implementation-effectiveness trial that modified the worksite choice architecture for healthy eating and daily physical activity.Methods: Fifty-three worksites participated in the 12-month intervention and implemented altogether 23 choice architecture strategies (Mdn 3/site), including point-of-choice prompts and changes to choice availability or accessibility. Retrospective acceptability evaluation built on deductive qualitative content analysis of implementer interviews (n = 65) and quantitative analysis of an employee questionnaire (n = 1124). Qualitative analysis examined implementers’ thoughts and observations of the intervention and its implementation, considering six domains of the Theoretical Framework of Acceptability: ethicality, affective attitude, burden, intervention coherence, opportunity costs, and perceived effectiveness. Quantitative analysis examined employees’ acceptance (7-point Likert scale) of eight specific intervention strategies using Friedman test and mixed-effects logistic regression.Results: Implementers considered the choice architecture approach ethical for workplace health promotion, reported mostly positive affective attitudes to and little burden because of the intervention. Intervention coherence supported acceptance through increased interest in implementation, whereas low perceived utility and high intensity of implementation reduced cost acceptance. Perceived effectiveness was mixed and varied along factors related to the implementer, social/physical work environment, employer, and employee. Employees showed overall high acceptance of evaluated strategies (Mdn 7, IQR 6.4–7), though strategies replacing unhealthy foods with healthier alternatives appeared less supported than providing information or enhancing healthy option availability or accessibility (p-values < 0.02). Greater proportion of male employees per site predicted lower overall acceptance (OR 4.4, 95% CI 1.2–16.5).Conclusions: Work communities appear to approve workplace choice architecture interventions for healthy eating and physical activity, but numerous factors influence acceptance and warrant consideration in future interventions. The study contributes with a theory-based, multidimensional evaluation that considered the perspectives of implementers and influenced individuals across heterogeneous real-world settings.
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