REN and type 2 diabetes mellitus: The development of T2DM in the GK rat is associated with chronic hyperglycemia [31, 32], activation of the renin-angiotensin system (RAS), and increased levels of oxidative stress [33–35] and inflammatory cytokines [2, 31, 32], all of which are known to have marked effects to activate PSCs and enhance their proliferation and generation of ECM.