SNP Study of DPP-4 and GLP-1R in Chinese People (Including Diabetes Patients)

NCT ID: NCT03108521

Last Updated: 2020-07-30

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE4
• Total Enrollment: 119 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-04-21
• Study Completion Date: 2018-10-08

Brief Summary

Incretin-based therapy is currently one of the most popular diabetes treatment approaches. However, differences of response ware found in previous studies. We hypothesis that SNPs of DPP-4, GLP-1 and GLP-1R genes may play crucial roles in the response differences. Therefore, this study aims to investigate the correlation of incretin-related gene polymorphism and individual differences in the response of DPP-4 inhibators (take Sitagliptin as an example). In addition, The distribution differences of the SNPs in diabetics and non-diabetics are evaluated to study the relationships between the SNPs and diabetes onsets.

Detailed Description

Single Nucleotide Polymorphism (SNP) plays an important role in the differences of clinical manifestations and drug responses of diseases. The vast majority of SNP sites are located in the non-coding region of the gene (about 95%), which is called SNP(non-coding SNP (ncSNP), while the other part of SNP is located in the coding region of the gene, which is called coding SNP (cSNP). Furthermore, cSNP can be divided into two categories: SNP that does not change the encoded amino acid sequence is called synonymous SNP(synonymous SNP, SSNP); SNP that changes amino acid sequence is called SNP(non-synonymous SNP (NSNP). Although not involved in coding amino acid, some ncSNPs may also affect the regulation of protein expression. Therefore, it is of great significance to study the effects of NC SNP and cSNP on the occurrence and development of diseases and drugs.

DPP-4 enzyme inhibitor is combined with DPP-4 enzyme in human body to reduce hydrolysis of active GLP-1, thus increasing the level of endogenous active GLP-1. Active GLP-1 combines with its receptor GLP-1R to promote insulin release and inhibit glucagon release in hyperglycemia state, and produces opposite effect in hypoglycemia state.

Based on the above principles, we speculate that SNP of genes that may affect the hypoglycemic effect of DPP-4 enzyme inhibitor are:

1. SNP of DPP-4 enzyme gene. SNP of DPP-4 enzyme gene may affect the enzyme activity and/or protein expression level of DPP-4. Assuming that the effect of DPP-4 enzyme inhibitor is sufficient, patients with higher DPP-4 enzyme activity are more sensitive to DPP-4 enzyme inhibitor drugs; However, for patients with low DPP-4 enzyme activity, DPP-4 enzyme inhibitor drugs cannot play a stronger role in lowering blood sugar.

2. SNP of GLP-1 gene. SNP of GLP-1 gene may affect activity or expression level of GLP-1. Patients with high GLP-1 level are more sensitive to DPP-4 enzyme inhibitor drugs.

3. SNP of GLP-1R gene. SNP of GLP-1R gene may affect activity or expression level of GLP-1R. Patients with high GLP-1R level are also more susceptible to DPP-4 enzyme inhibitor drugs.

However, studies on the hypoglycemic effect of DPP-4, GLP-1 and their receptors on DPP-4 enzyme inhibitors in the treatment of T2DM are rare, which is not conducive to the evaluation of individualized treatment of such drugs. Therefore, this chapter intends to select SNP sites with high mutation frequencies of DPP-4, GLP-1 and GLP-1R genes to study the mutation frequencies of these SNPs in diabetic patients and non-diabetic patients and their effects on DPP-4 enzyme inhibitor sitagliptin's hypoglycemic effect on T2DM patients.

Conditions

Diabetes Mellitus

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Sitagliptin group

Patients in this group will accept Sitagliptin phosphate tablets as their intervention. Specifications: Each tablet 100mg (with sitagliptin dollars). Regimen: The recommended dose is 100mg.QD for 3 months.

Group Type: EXPERIMENTAL

Sitagliptin

Intervention Type: DRUG

100mg.QD for 3 months

non-T2DM group

Subjects in this group are T2D free. We use their gene information to study SNP differences between T2D patients and non-T2DM people.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Sitagliptin

100mg.QD for 3 months

Intervention Type: DRUG

Other Intervention Names

Januvia

Eligibility Criteria

Inclusion Criteria

1. According to diagnostic criteria from Chinese type 2 diabetes prevention and treatment guidelines in diabetes, that published in the Chinese Medical Association Diabetes credits in 2010: Symptoms of diabetes (polydipsia, polyphagia, polyuria, weight loss, itchy skin, blurred vision and other acute metabolic disorders performance caused by hyperglycemia) and RBG≥11.1mmol/L, or fasting plasma glucose (FPG)≥7.0mmol/L, or plasma glucose of 2 hours post glucose-load≥11.1 and patients diagnosed with type 2 diabetes; HbA1c in the range of 7%-10%;

2. Age 40-70 years;

3. Body Mass Index(BMI) 18-40;

4. Did not accepted any antihyperglycemic therapies during the past 4 weeks, or did not change their antihyperglycemic treatment plan in the past 3 months;

5. Did not participate in clinical trials within three months;

6. No serious heart, brain, liver and kidney disease;

7. Signed informed consent.

Exclusion Criteria

1. Have taken any incretin drugs within recent 1 month;

2. Patients with a weakened immune system;

3. C-peptide < 0.3ng/ml;

4. GLP-1 and DPP4-i drugs allergies;

5. Pregnancy and breast-feeding patients;

6. Patients taking drugs that may affect the metabolism of GLP-1 and DPP4;

7. Patients have serious heart, liver, kidney and respiratory dysfunction; Patients have medullary thyroid carcinoma (MTC) with past history or family history, as well as multiple endocrine neoplasia type 2 syndrome (MEN2);

8. Drug abusing and alcoholism within a year.

For non-T2D group--

No major diseases such as tumors, no dyslipidemia, chronic diseases such as hypertension, and non-diabetic patients whose blood sugar and glycated hemoglobin values cannot meet the criteria for diagnosis of T2DM, and the age is over 50 years old.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 70 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Sichuan Provincial People's Hospital

OTHER

Sponsor Role: lead

Responsible Party

Enwu Long

Chief Pharmacist

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Enwu Long, Master

Role: PRINCIPAL_INVESTIGATOR

Director of Pharmacy department

Locations

Sichuan provincial people's hospital

Chengdu, Sichuan, China

Countries

China

References

Holman N, Young B, Gadsby R. Current prevalence of Type 1 and Type 2 diabetes in adults and children in the UK. Diabet Med. 2015 Sep;32(9):1119-20. doi: 10.1111/dme.12791. No abstract available.

Reference Type: BACKGROUND

PMID: 25962518 (View on PubMed)

Palermo A, Maggi D, Maurizi AR, Pozzilli P, Buzzetti R. Prevention of type 2 diabetes mellitus: is it feasible? Diabetes Metab Res Rev. 2014 Mar;30 Suppl 1:4-12. doi: 10.1002/dmrr.2513.

Reference Type: BACKGROUND

PMID: 24353270 (View on PubMed)

Lee YS, Jun HS. Anti-diabetic actions of glucagon-like peptide-1 on pancreatic beta-cells. Metabolism. 2014 Jan;63(1):9-19. doi: 10.1016/j.metabol.2013.09.010. Epub 2013 Oct 17.

Reference Type: BACKGROUND

PMID: 24140094 (View on PubMed)

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Other Identifiers

2015SZ0182

Identifier Type: -

Identifier Source: org_study_id