20 results on '"Mohan, V."'
Search Results
2. Design and analysis of solitary AC–AC converter using reduced components for efficient power generation system
- Author
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Nandakumar, K., Mohan, V., Alsaif, Faisal, and Senthilkumar, S.
- Published
- 2024
- Full Text
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3. Highly conductive anion exchange membranes based on polymer networks containing imidazolium functionalised side chains
- Author
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Ebrahim Abouzari-Lotf, Mohan V. Jacob, Hossein Ghassemi, Masoumeh Zakeri, Mohamed Mahmoud Nasef, Yadollah Abdolahi, Ali Abbasi, and Arshad Ahmad
- Subjects
Medicine ,Science - Abstract
Abstract Two novel types of anion exchange membranes (AEMs) having imidazolium-type functionalised nanofibrous substrates were prepared using the facile and potentially scalable method. The membranes’ precursors were prepared by graft copolymerization of vinylbenzyl chloride (VBC) onto syndiotactic polypropylene (syn-PP) and polyamide-66 (PA-66) nanofibrous networks followed by crosslinking with 1,8-octanediamine, thermal treatment and subsequent functionalisation of imidazolium groups. The obtained membranes displayed an ion exchange capacity (IEC) close to 1.9 mmol g–1 and ionic (OH-) conductivity as high as 130 mS cm–1 at 80 °C. This was coupled with a reasonable alkaline stability representing more than 70% of their original conductivity under accelerated degradation test in 1 M KOH at 80 °C for 360 h. The effect of ionomer binder on the performance of the membrane electrode assembly (MEA) in AEM fuel cell was evaluated with the optimum membrane. The MEA showed a power density of as high as 440 mW cm−2 at a current density is 910 mA cm−2 with diamine crosslinked quaternized polysulfone (DAPSF) binder at 80 °C with 90% humidified H2 and O2 gases. Such performance was 2.3 folds higher than the corresponding MEA performance with quaternary ammonium polysulfone (QAPS) binder at the same operating conditions. Overall, the newly developed membrane was found to possess not only an excellent combination of physico-chemical properties and a reasonable stability but also to have a facile preparation procedure and cheap ingredients making it a promising candidate for application in AEM fuel cell.
- Published
- 2021
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4. Highly conductive anion exchange membranes based on polymer networks containing imidazolium functionalised side chains
- Author
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Abouzari-Lotf, Ebrahim, Jacob, Mohan V., Ghassemi, Hossein, Zakeri, Masoumeh, Nasef, Mohamed Mahmoud, Abdolahi, Yadollah, Abbasi, Ali, and Ahmad, Arshad
- Published
- 2021
- Full Text
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5. Eco-friendly nanocomposites derived from geranium oil and zinc oxide in one step approach
- Author
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Al-Jumaili, Ahmed, Mulvey, Peter, Kumar, Avishek, Prasad, Karthika, Bazaka, Kateryna, Warner, Jeffrey, and Jacob, Mohan V.
- Published
- 2019
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6. Eco-friendly nanocomposites derived from geranium oil and zinc oxide in one step approach
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Peter Mulvey, Avishek Kumar, Mohan V. Jacob, Ahmed Al-Jumaili, Karthika Prasad, Kateryna Bazaka, and Jeffrey H. Warner
- Subjects
0301 basic medicine ,Materials science ,lcsh:Medicine ,chemistry.chemical_element ,One-Step ,Zinc ,engineering.material ,Article ,03 medical and health sciences ,0302 clinical medicine ,Coating ,X-ray photoelectron spectroscopy ,lcsh:Science ,chemistry.chemical_classification ,Multidisciplinary ,Nanocomposite ,Thin layers ,lcsh:R ,Thermal decomposition ,Polymer ,030104 developmental biology ,chemistry ,Chemical engineering ,engineering ,lcsh:Q ,030217 neurology & neurosurgery - Abstract
Nanocomposites offer attractive and cost-effective thin layers with superior properties for antimicrobial, drug delivery and microelectronic applications. This work reports single-step plasma-enabled synthesis of polymer/zinc nanocomposite thin films via co-deposition of renewable geranium essential oil-derived polymer and zinc nanoparticles produced by thermal decomposition of zinc acetylacetonate. The chemical composition, surfaces characteristics and antimicrobial performance of the designed nanocomposite were systematically investigated. XPS survey proved the presence of ZnO in the matrix of formed polymers at 10 W and 50 W. SEM images verified that the average size of a ZnO nanoparticle slightly increased with an increase in the power of deposition, from approximately 60 nm at 10 W to approximately 80 nm at 50 W. Confocal scanning laser microscopy images showed that viability of S. aureus and E.coli cells significantly reduced on surfaces of ZnO/polymer composites compared to pristine polymers. SEM observations further demonstrated that bacterial cells incubated on Zn/Ge 10 W and Zn/Ge 50 W had deteriorated cell walls, compared to pristine polymers and glass control. The release of ZnO nanoparticles from the composite thin films was confirmed using ICP measurements, and can be further controlled by coating the film with a thin polymeric layer. These eco-friendly nanocomposite films could be employed as encapsulation coatings to protect relevant surfaces of medical devices from microbial adhesion and colonization.
- Published
- 2018
7. Photostability of plasma polymerized γ-terpinene thin films for encapsulation of OPV
- Author
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Kateryna Bazaka, Jakaria Ahmad, Mohan V. Jacob, Michael Oelgemöller, and Ashraf Uddin
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Organic electronics ,chemistry.chemical_classification ,Multidisciplinary ,Materials science ,business.industry ,Energy conversion efficiency ,chemistry.chemical_element ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Oxygen ,Article ,0104 chemical sciences ,chemistry ,Chemical engineering ,Polymerization ,Photovoltaics ,Irradiation ,Thin film ,0210 nano-technology ,business - Abstract
Optically transparent, smooth, defect-free, chemically inert and with good adhesion to a variety of substrates, plasma polymers from plant-derived secondary metabolites have been identified as promising encapsulating materials for organic electronics and photovoltaics. Here, we demonstrate that an encapsulating layer of plasma polymerized γ-terpinene reduces degradation-related loss in conversion efficiency in PCPDTBT:PC70BM solar cells under ambient operating conditions. The stability of γ-terpinene films was then investigated under extreme UV irradiation conditions as a function of deposition power. When exposed to ambient air, prolonged exposure to UV–A and UV–B light led to notable ageing of the polymer. Photooxidation was identified as the main mechanism of degradation, confirmed by significantly slower ageing when oxygen was restricted through the use of a quartz cover. Under unnatural high-energy UV–C irradiation, significant photochemical degradation and oxidation occurred even in an oxygen-poor environment.
- Published
- 2017
8. Plant-derived cis-β-ocimene as a precursor for biocompatible, transparent, thermally-stable dielectric and encapsulating layers for organic electronics
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Ryan Destefani, Mohan V. Jacob, and Kateryna Bazaka
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Materials science ,Transistors, Electronic ,Polymers ,Band gap ,Acyclic Monoterpenes ,Biocompatible Materials ,02 engineering and technology ,Dielectric ,Alkenes ,010402 general chemistry ,01 natural sciences ,Article ,Materials Testing ,OLED ,Thermal stability ,Thin film ,chemistry.chemical_classification ,Organic electronics ,Multidisciplinary ,Plant Extracts ,business.industry ,Electrochemical Techniques ,Equipment Design ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Refractometry ,chemistry ,Thermodynamics ,Optoelectronics ,Adsorption ,0210 nano-technology ,business ,Layer (electronics) - Abstract
This article presents low-temperature, one-step dry synthesis of optically transparent thermally-stable, biocompatible cis−β−ocimene-based thin films for applications as interlayer dielectric and encapsulating layer for flexible electronic devices, e.g. OLEDs. Morphological analysis of thin films shows uniform, very smooth (Rq
- Published
- 2016
9. Photostability of plasma polymerized γ-terpinene thin films for encapsulation of OPV
- Author
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Bazaka, Kateryna, primary, Ahmad, Jakaria, additional, Oelgemöller, Michael, additional, Uddin, Ashraf, additional, and Jacob, Mohan V., additional
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- 2017
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10. Plant-derived cis-β-ocimene as a precursor for biocompatible, transparent, thermally-stable dielectric and encapsulating layers for organic electronics
- Author
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Bazaka, Kateryna, primary, Destefani, Ryan, additional, and Jacob, Mohan V., additional
- Published
- 2016
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11. An Improved Method for High Quality Metagenomics DNA Extraction from Human and Environmental Samples
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Bag, Satyabrata, primary, Saha, Bipasa, additional, Mehta, Ojasvi, additional, Anbumani, D., additional, Kumar, Naveen, additional, Dayal, Mayanka, additional, Pant, Archana, additional, Kumar, Pawan, additional, Saxena, Shruti, additional, Allin, Kristine H., additional, Hansen, Torben, additional, Arumugam, Manimozhiyan, additional, Vestergaard, Henrik, additional, Pedersen, Oluf, additional, Pereira, Verima, additional, Abraham, Philip, additional, Tripathi, Reva, additional, Wadhwa, Nitya, additional, Bhatnagar, Shinjini, additional, Prakash, Visvanathan Gnana, additional, Radha, Venkatesan, additional, Anjana, R. M., additional, Mohan, V., additional, Takeda, Kiyoshi, additional, Kurakawa, Takashi, additional, Nair, G. Balakrish, additional, and Das, Bhabatosh, additional
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- 2016
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12. Understanding the predictive accuracy of the InsuTAG index over other surrogate indices in normoglycaemic, non-obese males from Southern India.
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Jebasingh FK, Anoop S, Dasgupta R, Kurian ME, Joseph A, Rebekah G, Mohan V, and Thomas N
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- Adolescent, Humans, Male, Young Adult, Asian People, Blood Glucose, Fasting, Glucose Clamp Technique, India, Insulin, Insulin Resistance
- Abstract
We aimed to evaluate the predictive accuracy of InsuTAG index against M value of the hyperinsulinaemic-Euglycaemic clamp (HEC) procedure and fasting surrogate indices of insulin sensitivity/resistance in young, normoglycaemic, Asian Indian males. HEC studies were done in young (mean age 19.7 ± 1 years), non-obese (mean BMI 19.2 ± 2.6 kg/m
2 ), normoglycemic Asian Indian males (n = 110) and the M value was calculated. Surrogate indices namely InsuTAG index, HOMA-IR, FG-IR, QUICKI and McAuley index were calculated. Pearson's correlation and ROC-AUC at 95% CI were applied. Significant negative correlation was observed for InsuTAG index with the M value (r - 0.23, p = 0.01), McAuley index (r - 0.65, p < 0.01), QUICKI (r - 0.34, p < 0.01) and FGIR (r - 0.35, p < 0.01). Significant positive correlations of InsuTAG index were observed for BMI and waist circumference. The ROC-AUC was higher for InsuTAG index (0.75) than FGIR (0.30), QUICKI (0.31), and McAuley index (0.20). The InsuTAG cut-off value ≥ 19.13 showed 66.7% sensitivity and 69.2% specificity in this study group., (© 2023. The Author(s).)- Published
- 2023
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13. Identification of appropriate biochemical parameters and cut points to detect Maturity Onset Diabetes of Young (MODY) in Asian Indians in a clinic setting.
- Author
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Aarthy R, Aston-Mourney K, Amutha A, Mikocka-Walus A, Anjana RM, Unnikrishnan R, Jebarani S, Venkatesan U, Gopi S, Radha V, and Mohan V
- Subjects
- Adolescent, Humans, Cholesterol, HDL genetics, C-Peptide, Glycated Hemoglobin, India, Mutation, Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 1 diagnosis
- Abstract
Maturity Onset Diabetes of the Young (MODY) is a monogenic form of diabetes which is detected by genetic testing. We looked at clinical and biochemcial variables that could help detect possible MODY among Asian Indians with youth-onset diabetes. From the diabetes electronic medical records of a diabetes care centre in Chennai in southern India, demographic, anthropometric, and biochemical details of 34 genetically confirmed MODY participants were extracted. They were compared with patients with type 1 diabetes (T1D) (n = 1011) and type 2 diabetes (T2D) (n = 1605), diagnosed below 30 years of age. Clinical and biochemical variables including body mass index (BMI), glycated hemoglobin, HDL cholesterol, and C-peptide (fasting and stimulated) were analyzed to determine whether cut points could be derived to identify individuals who could be sent for genetic testing to diagnose or rule out MODY in this ethnic group. The age at diagnosis was higher for T2D (26.5 ± 4.0 years) compared to T1D (18.2 ± 6.1 years) and MODY (17.8 ± 6.0 years). Individuals with MODY had BMI, glycated hemoglobin, total cholesterol, triglycerides, HDL cholesterol, and C-peptide levels which were intermediate between T1D and T2D. The identified probable parameters and their cut points to identify cases for MODY genetic screening were BMI 21.2-22.7 kg/m
2 , glycated hemoglobin 7.2-10%, HDL cholesterol 43-45 mg/dl, fasting C -peptide, 1.2-2.1 ng/ml and stimulated C-peptide, 2.1-4.5 ng/ml. Asian Indians with MODY have clinical features that are intermediate between T1D and T2D and selected biochemical parameters, especially stimulated C peptide cut points were the most useful to diagnose MODY., (© 2023. The Author(s).)- Published
- 2023
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14. Development and validation of resource-driven risk prediction models for incident chronic kidney disease in type 2 diabetes.
- Author
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Gurudas S, Nugawela M, Prevost AT, Sathish T, Mathur R, Rafferty JM, Blighe K, Rajalakshmi R, Mohan AR, Saravanan J, Majeed A, Mohan V, Owens DR, Robson J, and Sivaprasad S
- Subjects
- Adult, Aged, Female, Glomerular Filtration Rate, Humans, Incidence, Male, Middle Aged, Prognosis, Renal Insufficiency, Chronic diagnosis, Risk Factors, Diabetes Mellitus, Type 2 complications, Renal Insufficiency, Chronic etiology
- Abstract
Prediction models for population-based screening need, for global usage, to be resource-driven, involving predictors that are affordably resourced. Here, we report the development and validation of three resource-driven risk models to identify people with type 2 diabetes (T2DM) at risk of stage 3 CKD defined by a decline in estimated glomerular filtration rate (eGFR) to below 60 mL/min/1.73m
2 . The observational study cohort used for model development consisted of data from a primary care dataset of 20,510 multi-ethnic individuals with T2DM from London, UK (2007-2018). Discrimination and calibration of the resulting prediction models developed using cox regression were assessed using the c-statistic and calibration slope, respectively. Models were internally validated using tenfold cross-validation and externally validated on 13,346 primary care individuals from Wales, UK. The simplest model was simplified into a risk score to enable implementation in community-based medicine. The derived full model included demographic, laboratory parameters, medication-use, cardiovascular disease history (CVD) and sight threatening retinopathy status (STDR). Two less resource-intense models were developed by excluding CVD and STDR in the second model and HbA1c and HDL in the third model. All three 5-year risk models had good internal discrimination and calibration (optimism adjusted C-statistics were each 0.85 and calibration slopes 0.999-1.002). In Wales, models achieved excellent discrimination(c-statistics ranged 0.82-0.83). Calibration slopes at 5-years suggested models over-predicted risks, however were successfully updated to accommodate reduced incidence of stage 3 CKD in Wales, which improved their alignment with the observed rates in Wales (E/O ratios near to 1). The risk score demonstrated similar model performance compared to direct evaluation of the cox model. These resource-driven risk prediction models may enable universal screening for Stage 3 CKD to enable targeted early optimisation of risk factors for CKD.- Published
- 2021
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15. Asymmetric dimethylarginine (ADMA) accelerates renal cell fibrosis under high glucose condition through NOX4/ROS/ERK signaling pathway.
- Author
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Jayachandran I, Sundararajan S, Venkatesan S, Paadukaana S, Balasubramanyam M, Mohan V, and Manickam N
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- Animals, Arginine adverse effects, Cell Line, Cell Movement drug effects, Cell Proliferation drug effects, Cells, Cultured, Fibroblasts cytology, Fibroblasts metabolism, Fibroblasts pathology, Fibrosis, Kidney cytology, Kidney metabolism, MAP Kinase Signaling System drug effects, Mesangial Cells cytology, Mesangial Cells metabolism, Mesangial Cells pathology, Models, Biological, Rats, Reactive Oxygen Species metabolism, Arginine analogs & derivatives, Diabetic Retinopathy metabolism, Glucose adverse effects, Kidney pathology, NADPH Oxidase 4 metabolism
- Abstract
We previously reported that the circulatory level of Asymmetric dimethylarginine (ADMA), an endogenous competitive inhibitor of nitric oxide synthase, was increased in diabetic kidney disease patients. However, the mechanism and the role of ADMA in diabetic kidney injury remain unclear. Hence, our principal aim is to investigate the causal role of ADMA in the progression of renal cell fibrosis under high glucose (HG) treatment and to delineate its signaling alterations in kidney cell injury. High Glucose/ADMA significantly increased fibrotic events including cell migration, invasion and proliferation along with fibrotic markers in the renal cells; whereas ADMA inhibition reversed the renal cell fibrosis. To delineate the central role of ADMA induced fibrotic signaling pathway and its downstream signaling, we analysed the expression levels of fibrotic markers, NOX4, ROS and ERK activity by using specific inhibitors and genetic manipulation techniques. ADMA stimulated the ROS generation along with a significant increase in NOX4 and ERK activity. Further, we observed that ADMA activated NOX-4 and ERK are involved in the extracellular matrix proteins accumulation. Also, we observed that ADMA induced ERK1/2 phosphorylation was decreased after NOX4 silencing. Our study mechanistically demonstrates that ADMA is involved in the progression of kidney cell injury under high glucose condition by targeting coordinated complex mechanisms involving the NOX4- ROS-ERK pathway.
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- 2020
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16. Plausible diagnostic value of urinary isomeric dimethylarginine ratio for diabetic nephropathy.
- Author
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Parmar D, Bhattacharya N, Kannan S, Vadivel S, Pandey GK, Ghanate A, Ragi NC, Prabu P, Pramodkumar TA, Manickam N, Mohan V, Sripadi P, Kuppan G, and Panchagnula V
- Subjects
- Adult, Aged, Albuminuria etiology, Albuminuria urine, Arginine urine, Chromatography, High Pressure Liquid, Cross-Sectional Studies, Diabetes Mellitus, Type 2 urine, Diabetic Nephropathies etiology, Diabetic Nephropathies urine, Feasibility Studies, Female, Humans, Male, Middle Aged, Predictive Value of Tests, ROC Curve, Tandem Mass Spectrometry, Albuminuria diagnosis, Arginine analogs & derivatives, Diabetes Mellitus, Type 2 complications, Diabetic Nephropathies diagnosis
- Abstract
Altered circulatory asymmetric and symmetric dimethylarginines have been independently reported in patients with end-stage renal failure suggesting their potential role as mediators and early biomarkers of nephropathy. These alterations can also be reflected in urine. Herein, we aimed to evaluate urinary asymmetric to symmetric dimethylarginine ratio (ASR) for early prediction of diabetic nephropathy (DN). In this cross-sectional study, individuals with impaired glucose tolerance (IGT), newly diagnosed diabetes (NDD), diabetic microalbuminuria (MIC), macroalbuminuria (MAC), and normal glucose tolerance (NGT) were recruited from Dr. Mohans' Diabetes Specialties centre, India. Urinary ASR was measured using a validated high-throughput MALDI-MS/MS method. Significantly lower ASR was observed in MIC (0.909) and MAC (0.741) in comparison to the NGT and NDD groups. On regression models, ASR was associated with MIC [OR: 0.256; 95% CI: 0.158-0.491] and MAC [OR 0.146; 95% CI: 0.071-0.292] controlled for all the available confounding factors. ROC analysis revealed ASR cut-point of 0.95 had C-statistic of 0.691 (95% CI: 0.627-0.755) to discriminate MIC from NDD with 72% sensitivity. Whereas, an ASR cut-point of 0.82 had C-statistic of 0.846 (95% CI: 0.800 - 0.893) had 91% sensitivity for identifying MAC. Our results suggest ASR as a potential early diagnostic biomarker for DN among the Asian Indians.
- Published
- 2020
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17. Perineuronal Net Protein Neurocan Inhibits NCAM/EphA3 Repellent Signaling in GABAergic Interneurons.
- Author
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Sullivan CS, Gotthard I, Wyatt EV, Bongu S, Mohan V, Weinberg RJ, and Maness PF
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- Animals, Cerebral Cortex cytology, Cerebral Cortex metabolism, Humans, Mice, Neural Cell Adhesion Molecules chemistry, Protein Binding, Protein Interaction Domains and Motifs, Receptor Protein-Tyrosine Kinases chemistry, Receptor, EphA3, GABAergic Neurons metabolism, Interneurons metabolism, Neural Cell Adhesion Molecules metabolism, Neurocan metabolism, Receptor Protein-Tyrosine Kinases metabolism, Signal Transduction
- Abstract
Perineuronal nets (PNNs) are implicated in closure of critical periods of synaptic plasticity in the brain, but the molecular mechanisms by which PNNs regulate synapse development are obscure. A receptor complex of NCAM and EphA3 mediates postnatal remodeling of inhibitory perisomatic synapses of GABAergic interneurons onto pyramidal cells in the mouse frontal cortex necessary for excitatory/inhibitory balance. Here it is shown that enzymatic removal of PNN glycosaminoglycan chains decreased the density of GABAergic perisomatic synapses in mouse organotypic cortical slice cultures. Neurocan, a key component of PNNs, was expressed in postnatal frontal cortex in apposition to perisomatic synapses of parvalbumin-positive interneurons. Polysialylated NCAM (PSA-NCAM), which is required for ephrin-dependent synapse remodeling, bound less efficiently to neurocan than mature, non-PSA-NCAM. Neurocan bound the non-polysialylated form of NCAM at the EphA3 binding site within the immunoglobulin-2 domain. Neurocan inhibited NCAM/EphA3 association, membrane clustering of NCAM/EphA3 in cortical interneuron axons, EphA3 kinase activation, and ephrin-A5-induced growth cone collapse. These studies delineate a novel mechanism wherein neurocan inhibits NCAM/EphA3 signaling and axonal repulsion, which may terminate postnatal remodeling of interneuron axons to stabilize perisomatic synapses in vivo.
- Published
- 2018
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18. Influence of depression on genetic predisposition to type 2 diabetes in a multiethnic longitudinal study.
- Author
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Garasia S, Samaan Z, Gerstein HC, Engert JC, Mohan V, Diaz R, Anand SS, and Meyre D
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- Case-Control Studies, Female, Follow-Up Studies, Humans, Longitudinal Studies, Male, Middle Aged, Quantitative Trait, Heritable, Depression genetics, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 psychology, Ethnicity genetics, Genetic Predisposition to Disease
- Abstract
We assessed the association between depression status and prevalent and incident type 2 diabetes (T2D) as well as the interaction between depression and a genetic risk score (GS) based on 20 T2D single-nucleotide polymorphisms (SNPs) in a multi-ethnic longitudinal study. We studied 17,375 participants at risk for dysglycemia. All participants had genotypic and phenotypic data collected at baseline and 9,930 participants were followed-up for a median of 3.3 years. Normal glucose tolerance (NGT), impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) and T2D statuses were determined using an oral glucose tolerance test and the 2003 American Diabetes Association criteria. Depression was diagnosed at baseline using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM IV). Multivariate logistic regression models were adjusted for age, sex, ethnicity and body-mass index and an interaction term GS X depression was added to the model. After appropriate Bonferroni correction, no significant association between depression and T2D-related traits (IFG/IGT, T2D and dysglycemia), and no significant interaction between the GS and depression status was observed at baseline or follow-up. Our longitudinal data do not support an association between depression and abnormal glycemic status. Moreover, depression does not modify the effect of T2D predisposing gene variants.
- Published
- 2017
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19. Longitudinal relationships between glycemic status and body mass index in a multiethnic study: evidence from observational and genetic epidemiology.
- Author
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Ishola AF, Gerstein HC, Engert JC, Mohan V, Diaz R, Anand SS, and Meyre D
- Subjects
- Adult, Blood Glucose, Body Mass Index, Diabetes Mellitus, Type 2 genetics, Female, Genetic Predisposition to Disease, Glucose Tolerance Test, Glycemic Index, Humans, Linear Models, Longitudinal Studies, Male, Middle Aged, Molecular Epidemiology, Observational Studies as Topic, Ethnicity genetics, Obesity genetics, Polymorphism, Single Nucleotide, Prediabetic State genetics
- Abstract
We investigated the relationship between glycemic status and BMI and its interaction with obesity single-nucleotide polymorphisms (SNPs) in a multi-ethnic longitudinal cohort at high-risk for dysglycemia. We studied 17 394 participants from six ethnicities followed-up for 3.3 years. Twenty-three obesity SNPs were genotyped and an unweighted genotype risk score (GRS) was calculated. Glycemic status was defined using an oral glucose tolerance test. Linear regression models were adjusted for age, sex and population stratification. Normal glucose tolerance (NGT) to dysglycemia transition was associated with baseline BMI and BMI change. Impaired fasting glucose/impaired glucose tolerance to type 2 diabetes transition was associated with baseline BMI but not BMI change. No simultaneous significant main genetic effects and interactions between SNPs/GRS and glycemic status or transition on BMI level and BMI change were observed. Our data suggests that the interplay between glycemic status and BMI trajectory may be independent of the effects of obesity genes. This implies that individuals with different glycemic statuses may be combined together in genetic association studies on obesity traits, if appropriate adjustments for glycemic status are performed. Implementation of population-wide weight management programs may be more beneficial towards individuals with NGT than those at a later disease stage.
- Published
- 2016
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- View/download PDF
20. Physical activity and genetic predisposition to obesity in a multiethnic longitudinal study.
- Author
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Reddon H, Gerstein HC, Engert JC, Mohan V, Bosch J, Desai D, Bailey SD, Diaz R, Yusuf S, Anand SS, and Meyre D
- Subjects
- Adult, Alleles, Body Mass Index, Ethnicity genetics, Female, Follow-Up Studies, Genetic Association Studies, Genotype, Humans, Longitudinal Studies, Male, Middle Aged, Patient Outcome Assessment, Polymorphism, Single Nucleotide, Risk, Genetic Predisposition to Disease, Motor Activity, Obesity epidemiology, Obesity genetics
- Abstract
Physical activity (PA) has been shown to reduce the impact of FTO variation and obesity genetic risk scores (GRS) on BMI. We examined this interaction using a quantitative measure of PA and two adiposity indexes in a longitudinal multi-ethnic study. We analyzed the impact of PA on the association between 14 obesity predisposing variants (analyzed independently and as a GRS) and baseline/follow-up obesity measures in the multi-ethnic prospective cohort EpiDREAM (17423 participants from six ethnic groups). PA was analyzed using basic (low-moderate-high) and quantitative measures (metabolic equivalents (METS)), while BMI and the body adiposity index (BAI) were used to measure obesity. Increased PA was associated with decreased BMI/BAI at baseline/follow-up. FTO rs1421085, CDKAL1 rs2206734, TNNl3K rs1514176, GIPR rs11671664 and the GRS were associated with obesity measures at baseline and/or follow-up. Risk alleles of three SNPs displayed nominal associations with increased (NTRK2 rs1211166, BDNF rs1401635) or decreased (NPC1 rs1805081) basic PA score independently of BMI/BAI. Both basic and quantitative PA measures attenuated the association between FTO rs1421085 risk allele and BMI/BAI at baseline and follow-up. Our results show that physical activity can blunt the genetic effect of FTO rs1421085 on adiposity by 36-75% in a longitudinal multi-ethnic cohort.
- Published
- 2016
- Full Text
- View/download PDF
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