en Endocrinology Endocrinology Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:14pt"><b><i><span style="color:blue">Background</span></i></b><i><span style="color:blue">:</span></i> Type 2 diabetes mellitus (T2DM), the most prevalent metabolic disorder worldwide, has genetic, epigenetic, and environmental contributors. Among them, circulating microRNAs (miRNAs/miRs) have attracted considerable attention. This study aimed to investigate the regulatory role of miR-103 in T2DM development. </span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Methods:</span></i></b> The miR-103 expression was evaluated in 33 participants with T2DM compared with 38 healthy controls using quantitative real-time polymerase chain reaction (q-RT PCR). Fasting blood glucose (FBS), fasting insulin (Fin), hemoglobin A1c (HbA1c), triglycerides (TG), and cholesterol (Chol) were also determined in serum. Basal insulin resistance and sensitivity were determined using the homeostasis model assessment insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI), respectively<span dir="RTL" lang="FA">.</span><span style="font-size:10.0pt"></span></span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Results:</span></i></b> There was a significant decrease in miR-103 levels in patients with T2DM (p<0.002). Serum miR-103 expression levels showed a strong correlation with age, FBS, HbA1c, TG, Chol levels, and HOMA-IR and QUICKI indices.</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Conclusion</span></i></b><i><span style="color:blue">:</span></i> The downregulation of miR-103 in T2DM patients suggests the diagnostic potential of miR-103 evaluation in conjunction with other diagnostic approaches.</span></span></span><br> &nbsp; MicroRNAs, miR-103, Type 2 Diabetes Mellitus, Insulin Resistance 106 113 http://caspjim.com/browse.php?a_code=A-10-3047-1&slc_lang=en&sid=1 Mahnoosh Rafiee mhn.rafiee@yahoo.com 100319475328460053470 100319475328460053470 No Farzin Sadeghi sadeghifarzin@gmail.com 100319475328460053471 100319475328460053471 No Ali Mirzapour a.mirzapour@gmail.com 100319475328460053472 100319475328460053472 No Soraya Khafri s.khafri@yahoo.com 100319475328460053473 100319475328460053473 No Bahare Korani koranib@gmail.com 100319475328460053474 100319475328460053474 No Atiyeh Al-e-Ahmad atiyeh_aleahmad@yahoo.com 100319475328460053475 100319475328460053475 No Hadi Parsian hadiparsian@yahoo.com 100319475328460053476 100319475328460053476 Yes Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran