Objective: To investigate the effect of curcumin on the structural change of microvasculature in STZ-induced diabetic rat’s liver.
Material and Method: Diabetic rats were induced by streptozotocin (60 mg/kg BW). Male rats were divided into three groups, control (C), diabetic (DM) and diabetic rats treated with curcumin (DMC) (200 mg/kg BW). After 8 weeks of experiments, blood vessels of rat’s liver were studied under conventional light microscope (LM) and vascular corrosion cast technique with scanning electron microscope (SEM).
Results: LM observation demonstrated that there were pathology and destruction of liver tissues and microvasculature in diabetic animals. The sinusoids around central veins were dilated and filled with red blood cells. There was an accumulation of lipid droplets in the cytoplasm of hepatocytes and hepatocyte nuclei showed pathological sign of pyknosis. Moreover, the inflammation change of liver tissues revealed the infiltration of lymphocytes and increasing of collagen deposition in the area of portal triad. In curcumin-treated rats, the distinguished recovery of liver tissues showed regained normal pattern of central veins, sinusoids, hepatocytes and portal triad, when compared with liver tissues of control group. By using vascular corrosion casting with SEM, the liver blood vessels of DM group revealed higher and expanded sizes, compared with control group; proximal parts of portal veins (C = 577.75 + 126.23, DM = 892 + 35.79, DMC = 469.5 + 85.53 μm), distal parts of portal veins (C = 76.72 + 1.48, DM = 200 + 31.05, DMC = 76.38 + 2.98 μm) and venules (C = 27.03 + 0.55, DM = 45.15 + 5.03, DMC = 28.38 + 3.67 μm) and corresponding to increased blood volumes compared with control group; proximal parts of portal veins (C = 20.8 + 1.28, DM = 62.2 + 3.39, DMC = 14.9 + 0.67 μm3), distal parts of portal veins (C = 0.46 + 0.03, DM = 3.81 + 0.18, DMC = 0.41 + 0.05 μm3) and venules (C = 0.05 + 0.05, DM = 0.24 + 0.013, DMC = 0.05 + 0.05 μm3) respectively. Fascinatingly, liver microvasculature in curcumin treated group developed into regenerate and repair into healthy and normal characteristics.
Conclusion: Efficiency of curcumin treatment beneficially repaired and regenerated liver tissues of diabetic groups and also redeveloped the liver’s microvascular complications. These results optimistically demonstrated the potential use of curcumin as a novel therapeutic agent in liver pathology of diabetic rats.

Keywords: Diabetes mellitus, Streptozotocin, Curcumin, Microvasculature, Vascular corrosion cast, SEM