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Circulating MicroRNA-15a Associates With Retinal Damage in Patients With Early Stage Type 2 Diabetes
Elena Sangalli1, Elena Tagliabue1, Lucia La Sala1
1IRCCS MultiMedica, Milan, Italy.
Abstract:
Circulating microRNAs are potential biomarkers of type 2 diabetes mellitus (T2DM) and related complications. Here, we investigated the association of microRNA-15a with early retinal damage in T2DM. A cohort of untreated subjects screened for intermediate/high risk of T2DM, according to a score assessment questionnaire, and then recognized to have a normal (NGT) or impaired (IGT) glucose tolerance or T2DM was studied. The thickness of the ganglion cell complex (GCC), an early marker of retinal degeneration anteceding overt retinopathy was assessed by Optical Coherence Tomography. Total and extracellular vesicles (EV)-associated microRNA-15a quantity was measured in plasma by real time PCR. MicroRNA-15a level was significantly higher in subjects with IGT and T2DM compared with NGT. MicroRNA-15a abundance was correlated to body mass index and classical diabetes biomarkers, including fasting glucose, HbA1c, insulinemia, and HOMA-IR. Moreover, GCC thickness was significantly reduced in IGT and T2DM subjects compared with NGT controls. Importantly, total microRNA-15a correlated with GCC in IGT subjects, while in T2DM subjects, EV-microRNA-15a negatively correlated with GCC, suggesting that microRNA-15a may monitor initial retinal damage. The assessment of plasma microRNA-15a may help refining risk assessment and secondary prevention in patients with preclinical T2DM.
Insights
Plasma microRNA-15a levels are elevated in individuals with impaired glucose tolerance and type 2 diabetes mellitus (T2DM). Higher microRNA-15a is linked to early retinal damage, suggesting its potential as a biomarker for T2DM complications.
Area of Science:
- Biochemistry
- Ophthalmology
- Endocrinology
Background:
- Circulating microRNAs (miRNAs) show promise as biomarkers for type 2 diabetes mellitus (T2DM) and its complications.
- Early detection of retinal damage in T2DM is crucial for preventing vision loss.
Purpose of the Study:
- To investigate the association between microRNA-15a and early retinal damage in individuals with T2DM.
- To explore microRNA-15a as a potential biomarker for preclinical T2DM and associated retinopathy.
Main Methods:
- Plasma samples from normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and T2DM subjects were analyzed for microRNA-15a levels using real-time PCR.
- Ganglion cell complex (GCC) thickness, an early indicator of retinal damage, was measured using Optical Coherence Tomography.
- Associations between microRNA-15a levels, clinical parameters, and GCC thickness were evaluated.
Main Results:
- MicroRNA-15a levels were significantly higher in IGT and T2DM groups compared to NGT.
- MicroRNA-15a levels correlated with body mass index and diabetes biomarkers (fasting glucose, HbA1c, HOMA-IR).
- Reduced GCC thickness was observed in IGT and T2DM subjects; microRNA-15a correlated with GCC thickness, particularly EV-associated microRNA-15a in T2DM patients.
Conclusions:
- Plasma microRNA-15a levels are elevated in individuals with glucose intolerance and T2DM.
- MicroRNA-15a, especially EV-associated forms, may serve as a biomarker for early retinal damage in T2DM.
- Assessing plasma microRNA-15a could aid in risk stratification and secondary prevention strategies for preclinical T2DM.
