ACE2 and type 2 diabetes mellitus: ANGII: angiotensin II; ACE: angiotensin-converting enzyme; ACE2: angiotensin-converting enzyme 2; AT1R: angiotensin receptor 1; AT2R: angiotensin receptor 2; HPA: hypothalamic-pituitary-adrenal; TACE: tumor necrosis factor/angiotensin convertase; OXs: orexins; ANG (1-7): angiotensin (1-7); OXA: orexin A; OXB: orexin B; ARDS: acute respiratory distress syndrome; OXRs: orexin receptors; T2DM: type 2 diabetes mellitus; GCs: glucocorticoids; CRH: corticotropin-releasing hormone; RAS: renin-angiotensin system.