Therapeutic effects of 1,25-dihydroxyvitamin D3 on diabetes-induced liver complications in a rat model.
It has been suggested that 1,25-dihydroxyvitamin D3 (vitamin D) plays a protective role against inflammation and insulin resistance (IR) in type 2 diabetes mellitus (T2DM). The present study investigate the hypothesis that vitamin D may exert beneficial effects on the liver in a rat model of T2DM by regulating the expression of inflammation-related cytokines and ameliorating IR induced by inflammation. Normal control group rats were fed a basic diet (NC). Experimental rats received a high-fat diet for 8 weeks and were then injected with streptozotocin (STZ) to induce T2DM. Half of the T2DM model rats received vitamin D (0.03 µg/kg/day) for 8 weeks (vitamin D-treated group; VD; n=11), while the other (T2DM group; DM; n=10) and NC group received an equivalent quantity of peanut oil. Following sacrifice, fasting plasma glucose (FPG) and fasting insulin (FINS) were recorded and homeostasis model assessment of IR (HOMA-IR) was calculated. Liver histopathology was examined using hematoxylin and eosin staining. The levels of the inflammatory cytokines C-Jun N-terminal kinase, C-Jun, tumor necrosis factor-α and interleukin-1β were measured using immunohistology, quantitative polymerase chain reaction and western blot analyses. The results revealed that treatment with vitamin D markedly alleviated the pathological alterations of liver and reduced the expression of inflammatory cytokines at the protein and mRNA levels. Furthermore, decreased levels of FPG, HOMA-IR and increased FINS were detected. In conclusion, the results of the present study indicate that vitamin D has therapeutic effects on diabetes-induced liver complications in T2DM model rats, which may involve the modulation of the inflammatory response, attenuating the crosstalk' between inflammation and IR and ameliorating hyperglycemic state.
Department of Endocrinology, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China.
Lina
L
Liu
Institute of Research, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China.
Guodong
G
Lv
Department of Endocrinology, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China.
Conghua
C
Ning
Department of Endocrinology, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China.
Y E
YE
Yang
Department of Endocrinology, The First Affiliated Hospital, Xinjiang Medical University, Urumqi, Xinjiang 830054, P.R. China.
Jun
J
Zhu
inflammation; insulin resistance; liver; type 2 diabetes mellitus; vitamin D