Training Induced Muscle-Adipose EV Communication
- Conditions
- Prediabetes
- Registration Number
- NCT07106450
- Lead Sponsor
- University of Kentucky
- Brief Summary
This study examines how muscle cells communicate with fat cells through tiny packages called extracellular vesicles (EV) during exercise. These vesicles carry important molecules that may affect how the body processes sugar and fat. The research team observed significant variability in the adipose response to exercise, and used this variability to gain further insight into the mechanism through which mature microRNA-1 (miR-1) changes in adipose tissue. The investigators selected six subjects with the highest increase in miR-1 abundance in adipose tissue after exercise and compared them with the six subjects that had the most dramatic decrease in miR-1 abundance after exercise. The research team observed that participants intrinsically vary in their ability to endocytose EV into adipose tissue. It is unclear whether this variance in receptivity is a cause or consequence of the significant difference in EV-delivery of miR-1 to adipose tissue.
- Detailed Description
This study investigates muscle-derived extracellular vesicle (EV) communication with adipose tissue and how this pathway is altered in pre-diabetes. The investigators will recruit 80 participants (40 euglycemic controls, 40 pre-diabetic) aged 18-30 years, equally distributed by sex. Pre-diabetes will be defined as impaired fasting glucose (100-125 mg/dL), impaired glucose tolerance (2-hour oral glucose tolerance test (OGTT) 140-199 mg/dL), or HbA1C 5.7-6.4%.
Following informed consent and medical screening at the Center for Clinical and Translational Sciences, participants will undergo baseline blood draw and tissue biopsies (subcutaneous adipose and vastus lateralis muscle) one hour prior to exercise. The resistance exercise protocol consists of whole-body resistance training at 80% 1RM (repetition maximum) intensity including bench press, leg press, and pull-downs. Blood samples will be collected immediately post-exercise and at 30, 60, and 90 minutes. Post-exercise biopsies will be obtained approximately 60 minutes after exercise cessation.
Laboratory analyses will include: (1) microRNA-1 (miR-1) quantification in adipose tissue by quantitative reverse transcription polymerase chain reaction (qRT-PCR) as the primary validated outcome of EV uptake; (2) fluorescently-labeled EV uptake assessment in cultured adipocytes using microscopy; (3) RNA sequencing (RNA-seq) of adipose tissue to identify transcriptomic signatures associated with EV uptake capacity; (4) primary cell culture studies using adult-derived human adipocyte stem cells (ADHASC); and (5) EV isolation and characterization using size exclusion chromatography and density gradient centrifugation.
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 80
- Age 30-55 years
- Sedentary lifestyle (exercise <1 day/week for at least 3 months prior to enrollment)
- Able to provide informed consent
- For Control Group: BMI < 27 kg/m², normal glucose tolerance, no more than 1 feature of metabolic syndrome
- For Prediabetic Group: BMI > 30 kg/m², at least 3 features of metabolic syndrome including prediabetes (defined as fasting plasma glucose 100-125 mg/dL OR 2-hour post-load glucose on 75g OGTT 140-199 mg/dL OR HbA1C 5.7-6.4%)
- Pregnancy (confirmed by pregnancy test in women of childbearing potential)
- Type 2 diabetes mellitus
- Cardiovascular contraindications to resistance exercise
- Medical conditions that would interfere with muscle or adipose tissue biopsy procedures
- Use of medications that significantly affect glucose metabolism or exercise response
- Active participation in structured exercise programs (>1 day/week) within 3 months of enrollment
- Inability to safely participate in resistance exercise protocol
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Primary Outcome Measures
Name Time Method miR-1 abundance in adipose tissue 60 minutes post-exercise (single measurement) Quantification of mature microRNA-1 levels in subcutaneous adipose tissue biopsies using quantitative Real Time-PCR as validated biomarker of in vivo extracellular vesicle uptake
Extracellular vesicle uptake capacity in primary adipocytes 24-48 hours post-isolation (in vitro culture) Measurement of fluorescently-labeled extracellular vesicle internalization in cultured primary adipocytes using confocal microscopy to quantify uptake rates in units of vesicles per minute per cell.
- Secondary Outcome Measures
Name Time Method Serum extracellular vesicle miR-1 content Baseline, 0, 30, 60, and 90 minutes post-exercise Time-course analysis of microRNA-1 abundance in isolated serum extracellular vesicles using quantitative RT-PCR to track temporal dynamics of muscle-derived vesicle release
Adipose tissue transcriptomic signatures 60 minutes post-exercise (single measurement) RNA-sequencing analysis of subcutaneous adipose tissue to identify differential gene expression patterns associated with high versus low extracellular vesicle uptake capacity, focusing on endocytotic pathways
Adrenergic receptor gene expression in adipose tissue 60 minutes post-exercise (single measurement) Quantitative RT-PCR measurement of ADRβ1, ADRβ2, and ADRβ3 receptor mRNA levels in subcutaneous adipose tissue as downstream targets of miR-1 delivery
Primary muscle miR-1 transcript levels 60 minutes post-exercise (single measurement) Quantification of pri-miR-1a and pri-miR-1b primary transcript abundance in vastus lateralis muscle biopsies using quantitative RT-PCR to assess exercise-induced miR-1 biogenesis