Metformin and Molecular Aging in Prediabetes

The Effect of Metformin Treatment on Surrogate Markers of Ageing (Leukocyte Telomere Length and Telomerase Activity), Longevity Gene Expression (Sirtuin 1, p66Shc, p53, Andmammalian Target of Rapamycin ), in North Indian Individuals With the Prediabetes: A Randomized Control Trial

The incidence and prevalence of type 2 diabetes mellitus (T2DM) are increasing globally. The global prevalence of diabetes has nearly doubled since 1980, rising from 4.7% to 8.5% in the adult population. Asian Indians have one of the highest incidence rates of pre-diabetes (10.3%) and type 2 diabetes mellitus (T2DM) (8.8%) among all major ethnic groups, and the conversion from pre-diabetes to diabetes occurs more rapidly in this population.

Metformin has been shown to effectively prevent the progression of prediabetes to overt diabetes. Furthermore, metformin improves lifespan in animal models through an anti-ageing pathway driven by mTOR. Metformin has also been shown to protect endothelial cells from hyperglycaemic damage by directly stimulating the expression of Sirtuin-1 (SIRT1), a deacetylase involved in metabolism and longevity by modulating SIRT1 downstream targets FoxO1 and p53/p21. It is important to note thatSIRT1, andmammalian target of rapamycin (mTOR) form a network that connects cellular metabolism and longevity programmes.

Only one study is available which has explored the relationship of metformin with longevity. Previous study conducted a single-blind randomized placebo-controlled trial in prediabetic subjects in Italy (n, 38) who received metformin 1500mg/day (n, 19) or placebo (n, 19) for 2 months. They demonstrated that metformin use significantly increased insulin sensitivity and metabolic parameters, SIRT1 gene/protein expression, and SIRT1 promoter chromatin accessibility. They also demonstrated that metformin use increased mTOR gene expression with a concurrent decrease in p70S6K phosphorylation and altered the plasma N-glycan profile. These authors concluded that in individuals with prediabetes, metformin ameliorated effector pathways that have been shown to regulate longevity in animal models.

The investigators recently did a study on 797 prediabetic women from north India (492 of whom were obese). In this study the investigators reported that age, obesity, and subcutaneous adiposity (predominantly truncal) are the main causes of leukocyte telomere shortening. It is yet unknown how metformin impacts aging-related genes and surrogate markers of ageing in the Asian Indian population.

This clinical trial aims to evaluate the effects of metformin treatment on surrogate markers of ageing (leukocyte telomere length and telomerase activity), in the setting of pre-diabetes. We intend to compare treatment with metformin for six months, versus placebo in pre-diabetic subjects. We will assess the surrogate markers of ageing (leukocyte telomere length and telomerase activity) and the expression of longevity genes SIRT1, p66Shc, p53 and mTOR in peripheral blood mononuclear cells (PBMCs) before and after 6 months of metformin treatment.

Study Overview

• Status: Completed
• Conditions: Metformin, Prediabetes
• Intervention / Treatment: Drug: Metformin treatment; Drug: Analyzed by qPCR for T/S ratio.

Detailed Description

Research methodology and outcomes measures:

1. Clinical History and Examination: Clinical history and blood pressure.
2. Body mass Index: BMI will be calculated by using formula weight (Kg)/height (m2).
3. Anthropometric Assessment: All circumferences (waist, hip, mid-thigh, mid arm and neck) and skinfolds (biceps, triceps, anterior axillary, subscapular, suprailiac, lateral thoracic and thigh) measurements will be taken. All the measurements will be repeated three times at same position and conditions.

4. Body Composition: Body composition will be measured through multi-frequency bioelectrical impedance (MF-BIA; InBody 770, Cerritos, CA, USA) Visit-2 (Day 90) Visit-3 (Day 180) Compliance check Enrolment of prediabetes subjects (BMI>25kg/m2) (n=112) Investigations: Fasting blood glucose, IGT (2h post-oral glucose load (75g) and HBA1c Group-I: Metformin Group (n=56) Group-II: Placebo Group (n=56) Final Analysis Measurements same as in visit 1 Baseline investigations: Clinical and dietary profiles, blood pressure, anthropometric assessments [body mass index, circumferences (waist, hip, mid-thigh, mid-arm and neck) and skinfolds (biceps, triceps, sub scapular, suprailiac, thigh, lateral thoracic and calf)], body fat, handgrip muscle strength, glycemic and lipid profile other metabolic parameters, fasting serum insulin, C-peptide and HOMA-IR,leukocyte telomerase length and telomerase activity and gene expression of SIRT1, mTOR, p53, p66Shc genes.

   Randomization: Visit 1 (Day 0) Screening Diet and exercise (run in two weeks) 5

5. Handgrip Muscle Strength: Grip strength will be measured using a Jamar Analogue Hand Dynamometer with participants seated, their elbow by their side and flexed to right angles, and a neutral wrist position, the dynamometer handle position II and provision of support underneath the dynamometer.
6. Biochemical measurements: The blood sample shall be drawn after 12 hours overnight fast, subject having taken normal diet in the previous three days. A 75-g OGTT will be performed. Blood samples shall be analyzed for following; blood glucose, A1C, lipids, fasting insulin, C-peptide, Homeostasis Model Assessment (HOMA)- Insulin Resistance (IR), and HOMA- Beta (ß%) and serum glucagon levels.
7. DNA Isolation and Quantification: DNA will be separated from peripheral blood mononuclear cells using the QIAamp DNA extraction kit (Qiagen, Hilden, Germany) and will be stored at -20oC for future experiments. After DNA isolation, the DNA samples will be quantified and diluted to 50 ng/μL. The concentration and quality of DNA will be both measured by using a nanodrop (Nanodrop Technologies, Wilmington, NC, USA) and samples will be included for analysis all will have an optical density ratio A 260/A280> 1.8. h) Measurement of Leukocyte Telomere Length: LTL will be analysed with a quantitative polymerase chain reaction (qPCR) based technique that compares telomere repeat sequence copy number (T) to a reference single copy-gene copy number (S). The telomere length for each sample will be estimated using the telomere to single copy gene ratio (T/S ratio) with the calculation of ΔCt [Ct (telomere)/Ct(single gene)]. T/S ratio for each sample (x) will be normalized to the mean T/S ratio of the reference sample [2-(ΔCtx-ΔCtr) = 2-ΔΔCt], which will be used for the standard curve, both as a reference sample and as a validation sample.

i) Gene expression by real-time PCR: Total RNA will be extracted using aRNeasy Mini Kit, (QIAGEN) cDNA and synthesized with an iScript cDNA synthesis kit (Bio-Rad, USA). Q-PCR assay will be performed in a Thermal Cycler (iCycler iQ5, Bio-Rad, Hercules, CA). Primers for Sirt1, p66Shc, p53, and mTORwill be designed from sequences derived from the GenBank database using Primer 3 (Whitehead Institute, Massachusetts, USA) and Operon's Oligo software (Operon, California, USA), purchased from Eurofins MWG (Ebersberg, Germany). The comparative threshold cycle method (ΔΔCq), which compares differences in the threshold cycle values between groups, will be used to obtain the relative fold change of gene expression.

• Study Type: Interventional
• Enrollment (Actual): 112
• Phase: Not Applicable

Contacts and Locations

Study Locations

• India
  • National Capital Territory of Delhi
    • New Delhi, National Capital Territory of Delhi, India, 110048
      • Anoop misra

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Age: 30-60 years Both genders (male and female)

Diagnosis of pre-diabetes, defined as:

Impaired Fasting Glucose (IFG): Fasting plasma glucose 100-125 mg/dL AND/OR Impaired Glucose Tolerance (IGT): 2-hour plasma glucose 140-199 mg/dL after 75 g oral glucose tolerance test (OGTT)

IGT is mandatory (i.e., every participant must have IGT, even if IFG is also present)

Exclusion Criteria:

Type 1 diabetes mellitus Type 2 diabetes mellitus Pregnancy or lactation Hypoglycemia (blood glucose <70 mg/dL) after medication Acute or chronic inflammatory diseases Immunological diseases (e.g., autoimmune diseases) History of organ transplantation Current or recent steroid therapy Uncontrolled arterial hypertension Known allergy or intolerance to metformin Major surgery or cardiovascular events (e.g., myocardial infarction, stroke) within the last 3 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: placebo for six months; Following a two-week diet and exercise run-in period, subjects will be randomized to receive either metformin (500mg twice daily after meals) or matching placebo for six months. All participants will monitor fasting and postprandial blood glucose (post-breakfast, post-lunch, post-dinner) monthly at home using a glucose meter. Both groups will maintain daily diaries recording tablet consumption and any missed doses. A three-month medication supply will be provided at each visit, with leftover tablets counted to assess compliance.	Drug: Metformin treatment; A computer-generated randomization sequence will be created by an independent statistician using an unrestricted scheme. Allocation will be concealed in serially numbered, sealed, opaque envelopes held by non-study office staff. After a two-week diet and exercise run-in period, subjects will be randomized to receive either metformin (500mg twice daily) or placebo for six months. Participants will monitor fasting and postprandial blood glucose monthly at home. Medication adherence will be tracked through daily diaries and pill counts at three-month visits. Compliance (target ≥85%) will be maintained through biweekly phone calls (urban areas), bi-monthly home visits by health workers (rural areas), and three-monthly motivational sessions.; Other Names: Placebo
Experimental: Effect of metformin treatment on Leukocyte telomere length; Analyzed by qPCR for T/S ratio.	Drug: Metformin treatment; A computer-generated randomization sequence will be created by an independent statistician using an unrestricted scheme. Allocation will be concealed in serially numbered, sealed, opaque envelopes held by non-study office staff. After a two-week diet and exercise run-in period, subjects will be randomized to receive either metformin (500mg twice daily) or placebo for six months. Participants will monitor fasting and postprandial blood glucose monthly at home. Medication adherence will be tracked through daily diaries and pill counts at three-month visits. Compliance (target ≥85%) will be maintained through biweekly phone calls (urban areas), bi-monthly home visits by health workers (rural areas), and three-monthly motivational sessions.; Other Names: Placebo; Drug: Analyzed by qPCR for T/S ratio.; Analyzed by qPCR for T/S ratio.
Experimental: To evaluate the effects of metformin treatment on telomerase activity; Telomerase activity was done by ELISA Mathod	Drug: Metformin treatment; A computer-generated randomization sequence will be created by an independent statistician using an unrestricted scheme. Allocation will be concealed in serially numbered, sealed, opaque envelopes held by non-study office staff. After a two-week diet and exercise run-in period, subjects will be randomized to receive either metformin (500mg twice daily) or placebo for six months. Participants will monitor fasting and postprandial blood glucose monthly at home. Medication adherence will be tracked through daily diaries and pill counts at three-month visits. Compliance (target ≥85%) will be maintained through biweekly phone calls (urban areas), bi-monthly home visits by health workers (rural areas), and three-monthly motivational sessions.; Other Names: Placebo
Experimental: Expression of longevity genes SIRT1, p66Shc, p53 and mTOR; Investigators were assessed the expression of longevity genes SIRT1, p66Shc, p53 and mTOR in peripheral blood mononuclear cells (PBMCs) before and after 6 months of metformin treatment.	Drug: Metformin treatment; A computer-generated randomization sequence will be created by an independent statistician using an unrestricted scheme. Allocation will be concealed in serially numbered, sealed, opaque envelopes held by non-study office staff. After a two-week diet and exercise run-in period, subjects will be randomized to receive either metformin (500mg twice daily) or placebo for six months. Participants will monitor fasting and postprandial blood glucose monthly at home. Medication adherence will be tracked through daily diaries and pill counts at three-month visits. Compliance (target ≥85%) will be maintained through biweekly phone calls (urban areas), bi-monthly home visits by health workers (rural areas), and three-monthly motivational sessions.; Other Names: Placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Leukocyte telomerase length	Leukocyte Telomere Length Measurement: LTL was analyzed using quantitative polymerase chain reaction (qPCR), comparing telomere repeat sequence copy number (T) to a reference single-copy gene (S). Relative fold changes in gene expression will be determined using the comparative threshold cycle method (ΔΔCq), comparing differences in threshold cycle values between groups.	06 months
Telomerase activity	Telomerase activity was done by ELISA method	06 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Expression of longevity genes SIRT1, p66Shc, p53 and mTOR	Total RNA will be extracted using aRNeasy Mini Kit, (QIAGEN) cDNA and synthesized with an iScript cDNA synthesis kit (Bio-Rad, USA). Q-PCR assay will be performed in a Thermal Cycler (iCycler iQ5, Bio-Rad, Hercules, CA). Primers for Sirt1, p66Shc, p53, and mTORwill be designed from sequences derived from the GenBank database using Primer 3 (Whitehead Institute, Massachusetts, USA) and Operon's Oligo software (Operon, California, USA), purchased from Eurofins MWG (Ebersberg, Germany). The comparative threshold cycle method (ΔΔCq), which compares differences in the threshold cycle values between groups, will be used to obtain the relative fold change of gene expression.	6 MONTHS

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight	Body weight was done by standard weight machine	06 month
Height	Height was done by slandered hight scale	06 months
Body Mass Index	BMI by using weight in kilograms (kg) divided by the square of height in meters (m2).	6 MONTHS
Circumferences	Measurement of circumferences (waist, hip, mid-thigh, mid-arm and neck) was measured with a flexible, non-stretchable tape measure	06 months
Skinfold thickness	Skinfolds (biceps, triceps, sub scapular, suprailiac, thigh, lateral thoracic and calf) was measured using skinfold calipers	06 months
Body Composition	Measured via MF-BIA (InBody 770, CA, USA).	6 MONTHS
Handgrip Muscle Strength	ssessed using a Jamar Dynamometer with elbows flexed.	6 MONTHS
Fasting and 75g OGTT	Blood samples were collected after a 12-hour fast for a 75-g OGTT, analyzing glucose	6 MONTHS
HAB1C	A1C was done by slandered laboratory	06 months
Lipids	Lipids were done by RANDOX kit	06 months
Insulin	Serum Insulin done by ELISA kit	06 months
C-peptide	C-peptide done by ELISA Kits	06 months

Collaborators and Investigators

• Sponsor: Diabetes Foundation, India

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2023
• Primary Completion (Actual): January 30, 2025
• Study Completion (Actual): January 30, 2025

Study Registration Dates

• First Submitted: November 24, 2025
• First Submitted That Met QC Criteria: December 11, 2025
• First Posted (Actual): December 24, 2025

Study Record Updates

• Last Update Posted (Actual): December 24, 2025
• Last Update Submitted That Met QC Criteria: December 11, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Nutritional and Metabolic Diseases; Prediabetic State
• Other Study ID Numbers: 2.5/FCDOC/EC/HAO/2022-23

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No