Gene Polymorphism Associated With Macroangiopathy in Type 2 Diabetes Patients

Completed

• Conditions: Diabetic Angiopathies
• Interventions: Other: Group A; Other: Group C; Other: Group B

• Registration Number: NCT02882945
• Lead Sponsor: First Affiliated Hospital of Harbin Medical University

Brief Summary

To explore the possible implications of HLA-DRB1\*04 alleles in patients with type 2 DM and macroangiopathy

Detailed Description

Previous studies examining the molecular etiology of diabetes mellitus in China and abroad have mainly focused on the relationship between HLA and type 1 diabetes mellitus (DM) (1-3). Due to the complexity of type 2 DM heredity, few researchers have studied the correlation between type 2 DM and HLA. In recent years, it has been suggested that the development of coronary heart disease (CHD) in diabetic individuals is not merely a complication of diabetic macroangiopathy. CHD and diabetic macroangiopathy share some genetic associations. Previous studies have demonstrated that certain HLA\*DRB1\*04 subtypes are associated with an increased risk of cardiovascular disease.

Experimental methods: For genomic DNA extraction, 3-5ml venous blood samples were collected from all patients. Coagulation was prevented using EDTA.

The procedure for PCR amplification was as follows: denaturing for 100s at 96°C, annealing for 60s at 63°C, 1 cycle; denaturing for 10s at 96°C, annealing for 60s at 63°C, 9 cycles; denaturing for 10 s at 96°C, annealing for 30 s at 59°C; extending for 30 s at 72°C, 20 cycles; maintaining at 4°C. Analyzing PCR products stained by Ethidium Bromide on 2.5% agarose gel electrophoresis. Bands were observed using an ultraviolet light and a biological imaging system.

Statistical method: The degree of agreement with Hardy-Weinberg equilibrium was determined using the χ2 test. A t-test was employed for comparison of CRP levels (M ± s) and a χ2 test was performed to compare allelic frequencies. The relative risk rate (RR) was calculated as (Number of patients with the gene×Number of people in control group without the gene) divided by (Number of people in control group with the gene×Number of the patients without the gene). PC was calculated using Fisher's method if χ2 \> 3.84.

Study Timeline

• Study Start: 2015-05
• Primary Completion: 2015-08
• Study Completion: 2015-09
• Status Verified: 2016-08
• Study First Submitted: 2016-08-25
• Study First Submitted QC: 2016-08-25
• Last Update Submitted: 2016-08-25
• Study First Posted: 2016-08-30
• Last Update Posted: 2016-08-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 470

Inclusion Criteria

• clinical CHD (such as angina pectoris, myocardial infarction) diagnosed by dynamic electrocardiogram and ultrasonic cardiogram;
• coronary atherosclerosis confirmed by coronary angiographic examination;
• cerebral infarction diagnosed by cerebral CT;
• common carotid artery intimal-media thickness (IMT) ≥1.2 mm measured by Doppler ultrasonic examination;
• extensive irregular stenosis of a lower extremity artery (diameter < 3mm) or segmentally obstructed.

Exclusion Criteria

• age < 20 years
• age > 60 years

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Group A	Group A	150 healthy blood donors without a family history of diabetes mellitus
Group C	Group C	120 cases of type 2 DM with macroangiopathy complication (group C), there were 70 males and 50 females, aged 40-53, with an average age of 47 ± 6 years. Among the group C subjects, 65 individuals had CHD; 55 patients had cerebrovascular disease (CVD); and 30 subjects had a combination of peripheral vascular diseases (PVD) and CHD
Group B	Group B	200 cases of type 2 DM without complications (group B), there were 62 males and 108 females, aged 29-53, with an average age of 42 ± 9 years

Primary Outcome Measures

Name	Time	Method
Test of allelic frequencies	At recruitment	A commercially available kit was used for extraction of genomic DNA from the whole blood samples (PEL-FREEZ Inc., USA). Thirty-two pairs of sequence-specific primers (SSP) for HLA-DRB1\*04 alleles were purchased from One Lambda, Inc. (USA), and the Taq enzyme was purchased from Promega Corp. (USA). The PCR-SSP technique was employed to determine the HLA-DRB1\*04 alleles for each subject. Genes were amplified using the 5700 PCR thermal cycler manufactured by Applied Biosystems Inc. (USA).

Secondary Outcome Measures

Name	Time	Method
Evaluation of serum CRP(C-reactive protein) levels	At recruitment	A commercially available 96-well plate ELISA assay kit (introassay CV 1.7%\~3.9%, interassay CV 2.8%\~5.1%) was used to quantify hs-CRP in serum (DSL Inc., USA). All samples were evaluated in duplicate. The absorbance (OD) was determined using a BIO-RAD2550 microwell plate reader (USA).