Risk Factors Analysis Of Type2Diabetes In Henan Urban Population And SIRT1and FOXO1SNPs Genetic Susceptibility To Type2Diabetic Nephropathy

BackgroundThe global prevalence of non-communicable chronic diseases, includingdiabetes, is rapidly increasing as a result of population ageing, urbanization andassociated lifestyle changes. Recently, the prevalence of diabetes has increaseddramatically in recent decades and the number of patients with diabetes in China evenmore than in India. Similarly, as the most populous province of China, the prevalenceof Type2diabetes mellitus (T2DM) in Henan province has increased significantly inrecent decades. Type2diabetes mellitus could result in multiple organ lesion, such ascardiovascular and cerebrovascular diseases, nephropathy, neuropathy and retinopathy.The health care costs for Type2diabetes has become a great financial burden to boththe patients and the whole society. There are no effective methods for the treatment ofdiabetes. Therefore, it is particularly important to prevent the disease to avoid thissituation sustainable development.As a result of environmental and genetic risk factors, lifestyle plays an importantrole in the development of T2DM. There are some studies concentrate on the riskfactors of T2DM, however, the results are different because of the world wide varietyof lifestyle caused by the different regional and ethnic difference. So far, the currentsituation and risk factors for type2diabetic patients in Zhengzhou is still unknown.Therefore, to investigate the prevalence situation and risk factors of type2diabetes inZhengzhou area is particular urgent. In addition, it is also very important tounderstand the impacts of family history on life style factors related type2diabetessince the family history of diabetes is an independent risk factors of T2DM. ObjectiveThe present study was designed to investigate the prevalence of type2diabetesmellitus，and combined with the T2DM family history (DFH) to analyze the impact offamily history on the lifestyle risk factors among Zhengzhou urban adult population.Study design and methodsThis study was the Henan part of the REACTION study，the Cross-sectionalsurvey was conducted in2010-2011. Adopting the random cluster sampling, sixcommunity were randomly selected in Zhengzhou, and10011integratedrepresentative ages30and older urban residents’ data were collected. Theinvestigation mainly includes questionnaire interview (demographic characteristics、family history of type2diabetes、lifestyle and behavioral risk factors、physical activity,diet, weight change, emotional state, etc.), physical examination (height, weight,waist circumference, hip circumference, blood pressure) and laboratory examination(fasting plasma glucose, OGTT-2h blood glucose). To conduct a comprehensiveanalysis of type2diabetes risk factors among ages30and older Zhengzhou urbanadult population.Risk ratios for the most relevant lifestyle variables were calculated byperforming a case-control study separately in DFH-positive and DFH-negative T2DMpatients and controls.1229patients with type2diabetes and8455subjects withoutdiabetes from the above subjects were involved in this study. According to with orwithout T2DM family history the case group and control group were further dividedinto family history positive DFH (+) group and family history of negative DFH (-)group.Results1. The prevalence of type2diabetes in Zhengzhou urban areaThe prevalence rate of type2diabetes for the ages30and older urban residentsin Zhengzhou province was12.72%(standard rate was12.01%), and the prevalencerates for males and females were12.62%,12.73%, respectively. There was nosignificant differences between males and females for the prevalence rates of type2 diabetes (P＞0.05).The prevalence rates of type2diabetes was no significantdifferences between Han and minority population (12.79%for Han vs.9.45%forminority)(P＞0.05).The prevalence rate of type2diabetes increased significantlywith the degree of education (χ2trend=35.813, Ptrend=0.000) and age (χ2trend=35.912,Ptrend=0.000). However, the prevalence rate of type2diabetes was no significantdifferences between different occupation population (P＞0.05).2. Risk factors of type2diabetes in Zhengzhou urban areaFor male: multiple logistic regression analysis showed that the family history ofdiabetes (OR=2.396,95%CI:1.840,3.120), systolic blood pressure levels (OR=1.535,95%CI:1.190,1.535), waist-hip ratio (OR=1.632,95%CI:1.343,1.632),degree of culture (OR=1.121,95%CI:1.012,1.121), potato intake frequency (OR=1.339,95%CI:1.115,1.339) were risk factors for type2diabetes.For female: multiple logistic regression analysis showed that the family historyof diabetes (OR=2.132,95%CI:1.783,2.550), age (OR=1.278,95%CI:1.124,1.278), alcohol drinking (OR=1.260,95%CI:1.0771.260), systolic blood pressurelevels (OR=1.840,95%CI:1.526,1.840), waist-hip ratio (OR=1.968,95%CI:1.648,1.968), degree of culture (OR=1.154,95%CI:1.075,1.154), potato intakefrequency (OR=1.264,95%CI:1.107,1.264) were risk factors for type2diabetes.Fruit intake frequency (OR=0.839,95%CI:0.735,0.957) was a protective factor fortype2diabetes.3. Comparison of Lifestyle Risk Factors by Family History for type2diabetesmellitusThe patients with type2diabetes family history suffering from diabetes with ayounger age compared with those without diabetes family history. After adjusted theage and sex, the number of risk factors of type2diabetes in DFH (+) group are lessthan DFH (-) group’s. Frequent intake of tuber and hypertension were the commonrisk factors for individuals regardless of the DFH status, while frequent intake offreshly squeezed vegetable and fruit juices was the only protective factor amongZhengzhou urban population. we haven’t seen ORs of the risk factors of high bloodpressure and tuber intake for DFH(+) group were lower than DFH(-) group’s.Whereas, some relatively hidden factors such as passive smoking、intaking pickle and etc，might increase the risk of suffering diabetes for DFH(+) population. Inaddition, it was also showed that some common risk factors for T2DM, such assmoking, drinking, obesity might increase the risk of diabetes for DFH (-) people.Conclusions1. The prevalence rate of type2diabetes for the ages30and older urbanresidents in Zhengzhou province was higher compared with the national average, andgrows rapidly. In less than20years, the prevalence of type2diabetes has increasedby nearly three times. The primary prevention of Type2should be a significantpriority for Zhengzhou province.2. Family history of type2diabetes, hypertension, obesity or overweight, degreeof culture and over potato intake are risk factors of type2diabetes for male inZhengzhou Provinces.Family history of type2diabetes, hypertension, alcohol drinking, obesity oroverweight, degree of culture and over potato intake are risk factors of type2diabetesfor female in Zhengzhou Provinces. Eating fruit frequently is a protective factor oftype2diabetes for female in Zhengzhou Provinces.3. The patients with type2diabetes family history suffering from diabetes with ayounger age compared with those without diabetes family history. The number ofRisk factors of type2diabetes in DFH (+) group are less than DFH (-) group’s. It wasindicated that frequent intake of tuber and hypertension were the common risk factorsfor individuals regardless of the DFH status while frequent intake of freshly squeezedvegetable and fruit juices was the only protective factor among zhengzhou urbanpopulation. The ORs of the risk factors of high blood pressure and tuber intake forDFH(+) group were no lower than DFH(-) group’s. According to the above lifestylemodification, these results suggested a limited influence of DFH on risk factors forT2DM，and DFH(+) population could reducing the susceptibility toT2DM bychanging their lifestyle. Diabetic nephropathy (DN) is a major late complication of diabetes that affectsapproximately40%of all patients with diabetes and remains the leading cause ofend-stage renal disease (ESRD) in the United States, and the second cause in China.however, the precise mechanism for Diabetic nephropathy is still unknown. Aprolonged duration,or inadequate metabolic and/or blood pressure control may explainsome cases. But even diabetic individuals with excellent control may still develop renalcomplications of their disease.The vast majority of the variability in incidentnephropathy remains unaccounted for by conventional risk factors. Whereas,investigations on the familial clustering of diabetic nephropathy in T2DM and theheritability of DN and its related traits provide compelling evidence that genetic factorscontribute to its susceptibility.SIRT1, an NAD+dependent deacetylase, may regulate multiple cellular functions,including apoptosis, mitochondrial biogenesis, inflammation, glucose/lipidmetabolism, autophagy, and adaptations to cellular stress, through the deacetylation oftarget proteins, including FOXO1.Previous studies have proved that they plays a keyrole in the development and progression of diabetes and diabetic nephropathy. Ourprevious reports have shown that SIRT1activated by resveratrol may increase theexpression of FOXO1, which increases its antioxidant target genes (CAT) to reduceROS level in the kidneys.These results indicate that SIRT1/FOXO1pathway may beconsidered a potential therapeutic target for DN.However， there are few studies concentrated on the accociation between theSIRT1and FOXO1gene single nucleotide polymorphisms (SNPs) and diabeticnephropathy. Shiro Maeda.et al identified4SNPs and haplotype consisting of the11 SNPs within SIRT1locus were nominally or significantly associated with diabeticnephropathy in Japanese people. Whereas, it has not been reported if the SIRT1genetic polymorphism is associated with diabetic nephropathy in Chinese population.In addition, although FOXO1gene involved in the susceptibility to type2diabeteshave been revealed in some previous studies, we still haven’t seen any study about theassociation between FOXO1gene and diabetic nephropathy.ObjectiveTo explore the genetic role of SIRT1and FOXO1in the development of T2DN,and environmental interactions in diabetic nephropathy suscepbility in Chinesesubjects with type2diabetes.MethodsA total of1066subjects were involved in this study. A case-control study wasperformed in Han Chinese population located in henan province.412patients withtype2diabetes and duration≥10years, no diabetic retinopathy,no diabeticnephropathy indicated urinary albumin excretion rate (UAER)<30mg/24h as controlgroup;654patients with type2diabetic nephropathy as case group. The case groupwere further classified into three subgroups:1)DN3,DN patients withmicroalbuminuria (30mg/24h≤UAER<300mg/24h or20μg/min≤UAER<200μg/min);2)DN4, DN patients with overt proteinuria， UAER≥300mg/24h or UAER300μg/min;3) DN5, DN patients with abnormal renal function (glomerular filtrationrate,GFR<90ml/min, including180cases with end-stage renal disease (ESRD)).TheUAER were measured at least twice for each subjects. Five SNPs (rs3818292,rs4746720, rs10823108in SIRT1) and (rs2721068， rs17446614in FOXO1) wereperformed genotyping by PCR-RFLP and DNA sequencing in Chinese han populationswith type2diabetes.SPSS17.0was used to describe the general characteristics of the sample and toanalysis genotypes distribution. Difference in the distribution of demographiccharacteristics and genotype frequencies between cases and controls were evaluatedusing the÷2-test.Hardy-Weinberg equilibrium，D’ linkage disequilibrium (LD) valueand haplotypes were analyzed by using SHEsis software.The associations between rs3818292, rs4746720, rs10823108, rs272106, rs17446614genotypes and risk ofT2DN were estimated by computing the odds ratio (ORs) and their95%confidenceinterval(Cl).Gene–gene and gene-environment ineractions were evaluated by using the MDRsoftware and logistic regression analysis．Results：1.Association of polymorphisms in SIRT1gene withT2DNThe results of single locus analysis revealed that GG genotype and (GG+AG)genotype carriers of SIRT1gene locus rs10823108had1.5times（OR=1.5，95%CI：1.03-2.66) and1.59times(OR=1.69,95%CI:1.11-2.78) higher risk of suffering fromT2DN than AA genotype carriers,respectively. In addition,the significance becomemore significant between DN3、DN4and control group.The distribution of GG genotype and (GG+AG) genotype of SIRT1gene loucsrs3818292is significant difference between the DN4group and Control group.GGgenotype carriers had0.21times lower risk of suffering from T2DN than AA genotypecarriers(OR=0.21，95%CI:0.07-0.71)； GG genotype carriers had0.22times(OR=0.22,95%CI:0.07-0.72)lower risk of suffering from T2DN than(AA+AG)g enotype carriers； G allele carriers had0.64times lower risk of sufferingfrom T2DN than A allele carriers(OR=0.64，95%CI：0.43-0.96).There is nosignificant difference of SIRT1rs4746720between case sample and control sample.No significant difference were found in haplotype analysis.2. Association of polymorphisms in FOXO1gene withT2DNThere is significant difference of FOXO1rs17446614in the comparison ofDN vs Control sample and DN subgroups vs Control sample. GG genotype genotypecarriers had lower risk of suffering from T2DN than AA genotype carriers,GAgenotype genotype carriers had lower risk of suffering from T2DN than AA genotypecarriers,and G allele carriers had lower risk of suffering from T2DN than A allelecarriers. Haplotype analysis show that haplotype defined by GT and GC can reducethe risk of T2DN,OR:0.77,95%CI:(0.63-0.93);OR:0.78,95%CI:(0.65-0.93).3.The interaction of SIRT1and FOXO1gene on the pathogenesis of T2DN The results of gene-environment interaction analysis presented a best modelincluding of two factors (rs17446614and hypertension), which could increase2.85-fold in the T2DN risk in the “high risk group”compared with the “low risk group”.4.Association of environmental factors and type2diabetic nephropathy.After adjusted the impacted factors,Logistic regression analysis suggested that therisk of type2diabetic nephropathy are associated with smoking, hypertension, HbA1C,total cholesterol level and high density lipoprotein cholesterol level,and thecorresponding of ORs and CIs were1.46(1.07-1.98); p<0.01;2.08(1.6-2.68), p=0.02;1.06(1.02-1.10), P<0.01;1.21(1.11-1.33),p<0.01;0.48(0.33-0.69),p<0.01. Noassociations were found between the following factors, including age,gender,bodymass index (BMI),alcohol drinking,serum triglycerides, low density lipoproteincholesterol level and family histories of diabetes with the risk of type2diabeticnephropathy.Conclusion：The SNPs within SIRT1and FOXO1might be involved in the process of diabeticnephropathy in Henan han Chinese case–control studies. GG genotype and GG+AGgenotype in SIRT1gene locus rs10823108, might increase the risk of T2DN,while GGgenotype and G allele in SIRT1gene locus rs3818292, and GG genotype, GA genotypeand G allele in FOXO1gene locus rs17446614might decrease the risk of T2DN. Thegene-environment interactions analysis suggested rs17446614in FOXO1andhypertension might be risk gene-environment interaction of T2DN. The T2DMpatients with smoking,hypertension,higher TC level and poor blood glucose controlwas associated with higher risk of DN,while those with higher plasma HDL levelwas associated with lower risk of DN.