LEP and type 2 diabetes mellitus: IR in T2DM is primarily associated with low-grade, tissue-specific inflammatory responses induced by various pro-inflammatory and oxidative stress mediators, notably pro-inflammatory cytokines such as interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and numerous chemokines and adipocytokines (e.g., leptin and resistin) (Rehman and Akash, 2016).