Morbidity in relation to stage of diabetic nephropathy in type-2 diabetic patients

AIMS OF THE STUDY: Type-2 diabetic patients have excessive cardiovascular mortality, primarily related to diabetic nephropathy. The extent of the morbidity due to nephropathy in type-2 diabetes mellitus has not been fully quantified in Nigeria. This study aims to quantify the prevalence of micro- and macrovascular complications in hospitalized type-2 diabetic patients with nephropathy. METHODS: Over a three-year period, 465 type-2 diabetic patients were examined for nephropathy and diabetic associated diseases while on hospital admission. RESULTS: One-hundred-ninety-one patients (41.1%) had signs of different stages of diabetic nephropathy. There is a predominance of the male sex in the nephropathic groups. Disease duration is lowest in the non-nephropathic group (6.5+/-7.1 years) but varies between 9.4+/-4.1 years and 11.7+/-3.5 years in the nephropathic groups. Hypertension, left ventricular hypertrophy, stroke, and myocardial infarction were less common in the non-nephropathic group, p<0.05, but showed an upward trend with progression of nephropathy. Although foot amputation was uncommon, the total percentage of patients with diabetic foot increased with progression of nephropathy (17% in non-nephropathic group versus 67% in patients with chronic renal insufficiency). The overall prevalence of diabetic retinopathy increased with progression of nephropathy, especially the occurrence of proliferative retinopathy. CONCLUSIONS: A high morbidity was already present even in patients without nephropathy that increased in the course of the development of nephropathy. The study identifies patients with diabetic nephropathy as a high-risk group for excess cardiovascular morbidity in Nigeria. Thus, it is imperative to aggressively prevent or slow down progression of diabetic nephropathy.     

Combinational effect of genes for the renin–angiotensin system in conferring susceptibility to diabetic nephropathy

To elucidate the role of the renin–angiotensin system (RAS) in diabetic nephropathy, we examined the association between diabetic nephropathy in a large cohort of Japanese type 2 diabetic patients and polymorphisms within the genes that encode angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II receptor type 1 (AGTR1). Single nucleotide polymorphisms (SNPs) within these genes were genotyped using invader assay in 747 nephropathy cases and 557 control subjects. Eight SNPs within the ACE gene were significantly associated with diabetic nephropathy (P<0.05), including five SNPs in almost complete linkage disequilibrium to the insertion/deletion polymorphism in the 16th intron (P=0.01, odds ratio =1.34, 95% CI 1.07–1.69). Three SNPs within the AGT, including M235T and one SNP in the AGTR1, were also significantly associated with nephropathy (M235T P=0.01, odds ratio =0.74, 95% CI 0.59–0.94). In addition, we found that the allelic mRNA expression corresponding to the 235M allele was significantly higher than that for the 235T allele in normal kidney tissues. Furthermore, we found a significant additional effect of these three genes by a step-wise logistic regression analysis (final empirical P value =0.00005). We concluded that RAS gene polymorphisms may contribute to the susceptibility to diabetic nephropathy in type 2 diabetes. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

Resequencing of the characterised CTGF gene to identify novel or known variants, and analysis of their association with diabetic nephropathy

Connective tissue growth factor (CTGF) has been implicated in the pathogenesis of diabetic nephropathy; however, to date there have been no reports of genomic analysis on this gene. The CTGF gene was comprehensively screened using WAVE (dHPLC) technology and direct capillary sequencing. Single nucleotide polymorphisms (SNPs) with minor allele frequencies greater than 5% were further investigated in an Irish, type 1 diabetic population. The case-control collection consisted of 272 diabetics with nephropathy and 367 non-nephropathic diabetic controls who were genotyped using TaqMan and Pyrosequencing technologies. Ten SNPs were identified, of which seven were novel. Four SNPs are located in the promoter, one in exon 2, two in intron 2 and three in the 3 untranslated region. Based on in silico analysis, three SNPs, c.–650G>C, c.–484T>C and c.247G>C, are potentially functional. Subsequent statistical analysis for common SNPs, c.–650G>C, c.–420InsT, c.–220G>C, c.289+94T>C and c.289+98T>C, in the case-control study revealed no significant differences in genotype or allele frequencies. CTGF has emerged as a biological candidate gene for diabetic nephropathy; however, no significant association was detected between common CTGF SNPs and nephropathy in this population.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.     

Interleukin (IL)-10 Gene Polymorphisms Are Associated with Type 2 Diabetes With and Without Nephropathy: A Study of Patients from the Southeast Region of Iran

The impact of several environmental and genetic factors on diabetes and its complications is well documented. It has also been established that cytokines play a key role in the regulation of immune responses which have been shown to be important in the pathogenesis of diabetes. Studies showed that single-nucleotide polymorphisms within the −592 region of interleukin-10 (IL-10) are associated with the regulation of its expression. In this study, we aimed to find polymorphisms of this region that may be associated to type 2 diabetic (T2D) patients with and without nephropathy. In this study, peripheral blood samples were collected from 100 T2D patients without nephropathy, 100 T2D patients with nephropathy, and 100 healthy controls. DNA was extracted, and a polymerase chain reaction-restriction fragment length polymorphism technique was performed to examine the polymorphisms within the −592 region of the IL-10 gene. Our results showed a significant difference between the genotypes and alleles of the −592 region of IL-10 in nephropathic and non-nephropathic patients in comparison to the healthy controls. The differences between the two patient groups in relation to genotypes and alleles were not significant. Results of this study suggest that the functional gene polymorphism of IL-10 reported here may play an important role in the pathogenesis of diabetes, but it seems that these polymorphisms do not have an effect on the nephropathic complications of the disease.     

Association of Polymorphisms in the Vitamin D Receptor Promoter with Idiopathic Short Stature

The genetic alterations of vitamin D receptor (VDR) are related with the growth of long bone. There were a lot of reports regarding an association of polymorphisms in the VDR promoter with many disorders, but not with idiopathic short stature (ISS). We investigated the association of them with ISS. A total of 50 subjects, including 29 ISS patients and 21 healthy controls with their heights within the normal range was recruited. We selected two single nucleotide polymorphisms (SNPs) from VDR promoter (rs11568820 at the Cdx-2 binding site upstream of exon 1e and rs4516035 at -1012 upstream of exon 1a) as candidates, respectively. In genotype analysis, the frequency of A/A genotype at the Cdx-2 binding site locus (rs11568820) upstream of exon 1e of VDR was decreased to 6.9% in ISS patients (28.6% in controls) (P = 0.027). The genetic variation at the Cdx-2 binding site of VDR promoter can be a contributing factor of growth of height.     

Association of rs11643718 SLC12A3 and rs741301 ELMO1 Variants with Diabetic Nephropathy in South Indian Population

This study reports on the association of genetic variants selected from previous genome‐wide association studies for type 2 diabetic nephropathy in south Indians. Eight variants were genotyped in 601 type 2 diabetic subjects without nephropathy (DM) and 583 type 2 diabetic subjects with nephropathy (DN) by MassARRAY. The minor allele frequencies of rs11643718 SLC12A3 variant and rs741301 ELMO1 variant were significantly different between DM and DN groups (P = 0.029 and 0.016, respectively). A combined analysis showed that the subjects carrying the risk genotypes of both these variants (GG of rs11643718 + AG/AA of rs741301) had a significant association with DN with an odds ratio [adjusted for age, sex, Body Mass Index (BMI), HbA1c, and systolic Blood Pressure (BP)] of 1.73 (1.30–2.30, P = 1.72 × 10^–4) as compared to subjects carrying all other genotype combinations. This is the first study to report a significant association of the SLC12A3 rs11643718 and ELMO1 rs741301 (Single nucleotide Polymorphism) SNPs with diabetic nephropathy in south Indians.     

The association of adiponectin serum level and ADIPOQ +45 T/G and ADIPOR1 −106 A/G gene polymorphisms with diabetic nephropathy in type 2 DM

Adiponectin encoded by ADIPOQ, gene (adiponectin, C1Q and Collagen Domain-Containing) is an adipocyte-derived protein, plays a major role in mediating insulin sensitivity, and lower plasma adiponectin concentration has been linked to microangiopathies in type 2 diabetes mellitus (DM). It has been hypothesized that blood adiponectin concentration may reflect the extent of kidney damage in diabetic patients. Our aim was to study genetic polymorphisms in adiponectin genes (ADIPOQ +45 T/G and adiponectin receptor 1 (ADIPOR1) ?106 A/G) and the serum level of adiponectin in type 2 DM and to correlate this with the stages of diabetic nephropathy. Forty-eight patients with type 2 DM were recruited from Internal Medicine Department and Nephrology Outpatient Clinic in Kasr El Aini Hospital, Cairo University, from April 2011 until March 2012. They were divided into normoalbuminuric (nonnephropathic), n?=?17; and nephropathic group, n?=?31; who were further subdivided into microalbuminuric, macroalbuminuric, and end-stage renal disease groups. They were compared to ten healthy control subjects. Blood urea, creatinine, HbA1c, and adiponectin were measured. ADIPOQ +45 T/G and ADIPOR1 ?106 A/G gene polymorphisms were analyzed by PCR RFLP. Serum adiponectin was significantly lower in nephropathic group versus nonnephropathic and control group (P?=?0.026) with the lowest level in macroalbuminuric group (P?<?0.001). Serum urea, blood glucose, HbA1c, and duration of diabetes were found to be independent predictors of adiponectin level, r ²?=?0.59. In case of ADIPOQ, most of the cases carried the TT genotype, and there was absence of GG genotype in both cases and control. The ADIPOR1 gene polymorphism was strongly associated with type 2 DM and diabetic nephropathy. The G allele of ADIPOR1 was found to be a risk factor for type 2 DM with OR 3.1 (95 % confidence interval 1.1–8.5), P?=?0.028. This evidence highlights the role of ADIPOR1 in the pathogenesis of diabetic nephropathy and type 2 diabetes (T2D), suggesting AdipoR1 as a promising target for the treatment of T2D patients, particularly those who have microalbuminuria. Also, adiponectin serum level is a biomarker for kidney disease and may be targeted for prevention and treatment.     

Novel polymorphisms of the human cholecystokinin a receptor gene: An association analysis with schizophrenia

The cholecystokinin A receptor (CCK‐AR) modulates CCK‐stimulated dopamine release in the posterior nucleus accumbens, and its gene is mapped to 4p15.2‐15.1 with the dopamine receptor 5 (DR5) gene. We speculated that alterations in the CCK‐AR lead to an increase in dopamine release, which may in turn constitute a predisposition in schizophrenia. We investigated genetic variations in the promoter region and the coding region of the CCK‐AR gene. An association analysis was conducted between 83 unrelated schizophrenic patients and 80 healthy controls. Novel polymorphisms (201A→G, 246G→A in the promoter region, 1260T→A, 1266T→C in intron 1 within the 3′ mRNA splice acceptor site consensus sequence, and Leu306Leu in exon 5) were found in addition to the variants (608G→A in intron 1, 3849C→T [Ile296Ile] in exon 5) reported previously. Significant differences were found in the allele frequencies of the 201A→G nucleotide substitution in the promoter region between patients and controls (P = 0.0181, odds ratio: 1.972, after Bonferroni correction: P = 0.0543). These differences were also found between the patients with paranoid type and controls (P = 0.0274, odds ratio = 3.667, after Bonferroni correction: P = 0.0822). Our analyses suggest that the 201A allele frequency was higher in the schizophrenic group, especially in the paranoid type, than in the control group at a rate that was not quite significant after Bonferroni correction. Am J. Med Genet. (Neuropsychiatr. Genet.) 96:141–145, 2000. © 2000 Wiley‐Liss, Inc.     

Impaired Primary Immune Response in Type-1 Diabetes: Results from a Controlled Vaccination Study

Patients with diabetes have an increased risk for infections, but information on their adoptive immunity is incomplete and contradictory. Twenty patients with diabetes type-1 and 20 patients with type-2 diabetes were vaccinated with T-cell-dependent primary protein antigens (hepatitis A viral antigen, HAV; diphtheria toxoid) and a T-cell-independent polysaccharide antigen (pneumococcal polysaccharide). In parallel, the proliferative response of CD4⁺ T-cells to the primary protein antigens keyhole limpet hemocyanin (KLH) and sperm whale myoglobin (SWM) was measured in vitro using monocyte-derived dendritic cells (MDDC) as antigen-presenting cells. Compared to healthy controls, type-1 diabetes patients mounted a significantly impaired primary antibody response to hepatitis A vaccine (median HAV antibody titer after the first vaccination, 53 IU/L in diabetic patients vs 212 IU/L in the controls, P = 0.017) and diphtheria toxoid (median serum antibodies after vaccination, patients, 0.94 IU/ml, controls, 6.38 IU/ml, P = 0.004), while the response to pneumococcal polysaccharide was normal. Type-2 diabetes patients had a comparable metabolic dysregulation but showed a normal antibody response following vaccination, demonstrating that the effect was not due to hyperglycemia. Antigen-induced interferon-γ and interleukin-13 release was reduced in type-1 diabetes patients, localizing the impairment to the level of antigen-presenting cell–T-cell interaction. In addition, the proliferative response of CD4⁺ T-cells derived from type-1 diabetes patients to KLH and SWM was significantly reduced (P ≤ 0.01). FACS analysis of CD80 (B7.1), CD86 (B7.2), and HLA-DR expression on MDDC could not demonstrate significant differences in the expression of these molecules between type-1 and type-2 diabetes patients and healthy controls. An association of low HAV antibody response with HLA-DR3,4 expression in the patients was shown. Our results indicate that the primary antibody response to T-cell dependent antigens as well as the T-cell response to primary protein antigens is reduced in type-1 diabetes patients and that additional booster immunization can overcome the defect.     

The polymorphism of manganese superoxide dismutase is associated with diabetic nephropathy in Japanese type 2 diabetic patients

 We evaluated the relationship of an alanine or valine polymorphism at amino acid sequence 16 [Val(16)Ala] of manganese superoxide dismutase (Mn-SOD) with diabetes and diabetic nephropathy in Japanese type 2 diabetic patients. Val(16)Ala genotyping of Mn-SOD was done by polymerase chain reaction-restriction fragment length polymorphism with a restriction enzyme (Bsaw I) in 478 Japanese type 2 diabetic patients and 261 nondiabetic Japanese healthy subjects. The genotype distribution of diabetic and nondiabetic subjects was then compared, and the association of genotype with diabetic nephropathy was evaluated in the diabetic patients. The allele frequency and genotype of the diabetic patients were not different from those of the healthy nondiabetic subjects. The VV type showed a significantly higher frequency in the diabetic patients with nephropathy than did the AA or VA type [VV type: normoalbuminuria 70.8%, microalbuminuria 84.8% (P = 0.0057), macroalbuminuria 84.1% (P = 0.0128)]. Furthermore, logistic regression analysis showed that this polymorphism is associated with diabetic nephropathy independently (odds ratio = 0.461925, P = 0.03). Accordingly, the Val(16)Ala polymorphism of Mn-SOD may be unrelated to the etiology of type 2 diabetes, but it seems to be associated with diabetic nephropathy in Japanese type 2 diabetic patients. Received: August 5, 2002 / Accepted: December 3, 2002 Correspondence to:Y. Tanaka     

A SNP in the ACT gene associated with astrocytosis and rapid cognitive decline in AD

There is biochemical and animal model evidence supporting a pathological role of the ACT gene in AD. However, direct genetic evidence remains controversial and has been mostly limited to individual single nucleotide polymorphism (SNP) analysis. To resolve this apparent conflict we have used a high-density ACT SNP map, constructed haplotypes and explored correlations with phenotype. SNPs were identified by sequencing and used to construct haplotypes in 668 AD patients and 419 controls and a case–control association study was performed. Five SNPs, comprising five common haplotypes, represented 93% of ACT gene variation. Although no single SNP or haplotype was associated with AD status, a SNP in intron 2 was associated with later onset and more rapid cognitive decline (P = 0.04). This SNP was both individually associated with severe astrocytosis (P = 0.004) in AD patients and when combined with the signal sequence SNP (P = 0.002). This suggests that astrocytosis may have a protective function for a limited period in some patients. These SNP associations either support a direct role for the ACT gene, in AD pathology or alternatively reflect linkage with polymorphisms in other genes nearby.     

IFN-γ基因多态性与内蒙古汉族IgA肾病易感性关系的研究

目的:探讨IFN-γ基因+874位点单核苷酸多态性与内蒙古汉族IgA肾病患者易感性的关系.方法:从131例内蒙古汉族IgA肾病的患者和138例健康对照者外周血中提取DNA,采用序列特异性引物聚合酶链反应(PCR-SSP)技术检测IFN-γ基因+874位点单核苷酸多态性.比较两组的基因型和等位基因的分布.结果:IgA肾病...     

No role for estrogen receptor 1 gene intron 1 Pvu II and exon 4 C325G polymorphisms in migraine susceptibility

Background  

We have previously reported an association between the estrogen receptor 1 (ESR1) gene exon 8 G594A polymorphism and migraine susceptibility in two independent Australian cohorts. In this paper we report results of analysis of two further single nucleotide polymorphisms (SNPs) in the ESR1 gene in the same study group, the T/C Pvu II SNP in intron 1 and the C325G SNP in exon 4, as well as results of linkage disequilibrium (LD) analysis on these markers.     

Analysis of Functional SNP in Ifng/Ifngr1 in Chinese Han Population with Tuberculosis

Ifng/Ifngr1 are the main genes that are associated with tuberculosis. We continued to search for other functional single nucleotide polymorphisms (SNP) and investigated their influence on patients with tuberculosis in the Chinese population. Seven SNP located in the ifng and ifngr1 genes were genotyped by ligase detection reaction in 222 cases and 188 ethnically matched controls. A significant genetic association between rs7749390 (located on the exon/intron splice site of the ifngr1 gene) and tuberculosis was observed, and the log‐additive model was accepted as the best inheritance model to fit these data (OR: 1.35, 95% CI: 1.02–1.80, P = 0.038). Haplotype‐specific association analysis revealed that the result was consistent with the individual SNP study. The combination of rs2234711/rs1327474/rs7749390/rs41401746, which was in strong linkage disequilibrium (D′ > 0.75), showed a significant association of ifngr1 with tuberculosis (P = 0.00079). Neither the single SNP nor the haplotype analysis showed a significant association between tuberculosis and the ifng gene markers. Our data implied the involvement of the ifngr1 gene in susceptibility to tuberculosis.     

Association of VKORC1 and CYP2C9 polymorphisms with warfarin dose requirements in Japanese patients

Warfarin is the most commonly used oral anticoagulant for treatment of thromboembolism, but adjustment of the dose appropriate to each patient is not so easy because of the large inter-individual variation in dose requirement. We analyzed single nucleotide polymorphism (SNP) genotypes of the VKORC1 and CYP2C9 genes using DNA from 828 Japanese patients treated with warfarin, and investigated association between SNP genotype and warfarin-maintenance dose. Five SNPs in VKORC1, 5 flanking–1413A>G, intron 1–136T>C, intron 2+124C>G, intron 2+837T>C and exon 3 343G>A, were in absolute linkage disequilibrium, and showed a significant association with daily warfarin dose of these patients. The median warfarin dose of patients with homozygosity for the minor allele was 4.0 mg/day, which is significantly higher than those heterozygous for the minor allele (3.5 mg/day) or those homozygous for the major allele (2.5 mg/day; P=5.1×10^–11 in the case of intron 1–136T>C SNP). We then genotyped the CYP2C9 gene for the Japanese common genetic variant, CYP2C9*3 and, based on the genotype of these two genes, classified patients into three categories, which we call warfarin-responsive index. The median warfarin daily dose varied significantly in this classification according to the warfarin-responsive index (2.0 mg/day for index 0 group, 2.5 mg/day for index 1 group, and 3.5 mg/day for index 2 group; P=4.4×10^–13). Thus, analysis of the combination of VKORC1 and CYP2C9 genotypes should identify warfarin-sensitive patients who require a lower dose of drug, allowing personalized warfarin treatment.     

甲基四氢叶酸还原酶基因多态性与糖尿病肾病关系的研究

目的：探讨甲基四氢叶酸还原酶（methylenetetrahydrofolate reductase,MTHFR)基因多态性与糖尿病肾病（diabetic nephropathy,DN)发生的关系。方法：利用聚合酶链反应－限制性片段长度多态性分析法（PCR－RFLP）检测了85名健康人和经尿微量白蛋白检测确诊的82例合并DN和79例无DN的2型糖尿病患者MTHFR基因第677位碱基多态性。结果：DN患者MTHFR基因变异型纯合子和等位基因频率均明显高于无肾病患者及健康者,P＜0．01。结论：MTHFR基因第677位碱基变异可能是中国汉族人DN发生的一个遗传危险因子。     

Genetic variants in <Emphasis Type="Italic">PCSK9</Emphasis> affect the cholesterol level in Japanese

Mutations in the proprotein convertase subtilisin/kexin 9 (PCSK9) gene have been reported in affected members of two families with autosomal dominant hypercholesterolemia. To investigate the effects of common variants in PCSK9 on the cholesterol level, we conducted an association study using a large cohort representing the general population in Japan (n=1,793). Direct sequencing in all of the exonic regions identified 21 polymorphisms. After consideration of linkage disequilibrium among these polymorphisms, we selected and genotyped nine polymorphisms by the TaqMan method. The intron 1/C(-161)T and exon 9/I474 V polymorphisms were associated with levels of total cholesterol (TC) [C(-161)T, P=0.0285; I474 V, P=0.0069] and low-density lipoprotein cholesterol (LDL-C) [C(-161)T, P=0.0257; I474 V, P=0.0007]. The distributions of these polymorphisms in subjects with miocardial infarction (MI) (n=649) were not different from those in the control population. These results provide the first evidence that common variants intron 1/C(-161)T and exon 9/I474 V in PCSK9 significantly affect TC and LDL-C levels in the general population in Japan.