Scutellarin protects against diabetic cardiomyopathy via inhibiting oxidative stress and inflammatory response in mice.

Background: Scutellarin (Scu) shows both anti-inflammatory and antioxidant activities. The study investigates cardioprotective effects of Scu in mice with type 1 diabetes and the underlying molecular mechanism.

Methods: Streptozotocin (STZ) was used to induce diabetic cardiomyopathy (DCM) in C57BL/6 mice by intraperitoneal injection (i.p.). Normal and diabetic mice were divided into 6 groups: control, diabetic model group (DM), DM + Scu (5 mg/kg), DM + Scu (10 mg/kg), DM + Scu (20 mg/kg), DM + pioglitazone (Pio) (10 mg/kg). Scu was administered to the mice intraperitoneally and Pio was administrated by oral. Mice in control and DM groups were simply treated normal saline. Four weeks later, myocardial function, myocardial fibrosis, the levels inflammatory factors and oxidative stress were detected.

Results: Scu improved cardiac function and reduced heart injury in diabetic mice, which was indicated by increasing Left ventricular (LV) end-diastolic volume (LVVd), fractional shortening (FS), and ejection fraction (EF) levels and decreased pathological changes of heart. Scu inhibited the level of myocardial fibrosis by reducing the release of inflammatory cytokines and increasing activities of antioxidant enzymes. Further study showed that Scu inhibited the activation of nucleotide-binding oligomerization domain-like receptor with a pyrin domain 3 (NLRP3) and nuclear factor-kappa B (NF-κB) and activated phospho-protein kinase B (p-AKT), nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase (HO-1).

Conclusions: Scu protects against DCM in STZ-induced diabetic mice by inhibiting oxidative stress and inflammatory responses and might be a potential therapeutic agent to treat DCM.