- 學位論文
土肉桂葉精油對糖尿病大鼠之抗氧化及抗發炎作用
The antioxidative and anti-inflammatory effects of leaf essential oil of Cinnamomum osmophloeum Kaneh. on diabetic rats
摘要
本研究室過去研究發現，台灣本土土肉桂葉精油 (TC) 對DM大鼠具有改善口服葡萄糖耐受性及胰島素耐受性之功能。本研究目的為觀察TC對DM大鼠氧化壓力及發炎反應之影響。實驗以STZ (65 mg/kg BW) 誘發大鼠DM，隔日灌食低、中或高劑量精油 (13、26或54 mg/kg BW) 及肉桂醛 (40 mg/kgBW；CA)，且以口服降血糖藥glibenclamide (1.2 mg/kgBW；GC) 做為正控制組，共灌食八次。結果發現，TC顯著逆轉DM所增加之胰臟、骨骼肌及周邊血中脂質過氧化程度，且在胰臟及周邊血之改善效果顯著優於CA及GC。此外，TC顯著提升DM大鼠骨骼肌、胰臟及腎臟抗氧化酵素Superoxide dismutase (SOD)、Glutathione reductase (GRd) 及Glutathione peroxidase (GPx) 活性，在骨骼肌及腎臟中效果優於CA及GC，而在胰臟中效果與CA相當但優於GC。TC顯著增加DM大鼠骨骼肌、胰臟及腎臟中總麩胱甘肽 (GSH) 含量，效果均優於CA及GC。另外，在周邊血中TC可顯著增加抗氧化酵素SOD及GPx之活性且也可顯著增加GSH含量，效果與CA相當但優於GC。在抗發炎作用方面，TC顯著逆轉DM所增加之骨骼肌、胰臟、腎臟及周邊血中IL-1β、TNF-α及一氧化氮衍生物(NO)濃度，在胰臟中效果優於CA及GC，在骨骼肌、腎臟及周邊血中效果與CA相當但優於GC。由本研究結果得知，土肉桂葉精油在糖尿病狀態下具抗氧化及抗發炎效果，且抗氧化作用優於肉桂醛，推論其作用成分除了肉桂醛外尚來自於精油中其他成分。
並列摘要
According to previous study, cinnamon extract have functions of anti-diabetic effect. Our previous study found the leave essential oil of Cinnamomum osmophloeum Kaneh. (TC) can improve oral-glucose tolerance and insulin tolerance in diabetic rats. The aim of the present study is to investigate the effect of TC on oxidative stress and inflammatory condition in diabetes. Male Wistar rats were induced to be diabetes with Streptozotocin (STZ, 65 mg/kg BW) and received every other day for eight times by gavage low, medium or high dose of TC (13、26 or 54 mg/kg BW), Cinnamaldehyde (CA, 40 mg/kg BW), glibenclamide (GC, 1.2 mg/kg BW) or vehicle (corn oil, 2 ml/kg BW). Rats of control group received corn oil only and injected with saline. TC significantly reversed the lipid peroxidation in skeletal muscle, pancreas and peripheral blood in diabetes and was more effective than that of CA and GC. TC significantly reversed activities of antioxidant enzymes, SOD, GRd and GPx in skeletal muscle, pancreas and kidney in diabetes, and showed to be more effective than that of CA and GC in skeletal muscle and kidney, and more effective than that of GC in pancreas. TC also significantly reversed total GSH content in skeletal muscle, pancreas, and kidney in diabetic rats to an extent greater than that of CA and GC. In addition, TC significantly reversed activities of SOD and GPx, and total GSH level in peripheral blood to an extent similar to that of CA and greater than that of GC. In the other hand, TC significantly reversed levels of IL-1β, TNF-α, and NO on skeletal muscle, pancreas, kidney, and peripheral blood of diabetic rats, and showed to be more effective than that of CA and GC in pancreas, and more effective than that of GC on skeletal muscle, kidney and peripheral blood. In conclusion, the present study demonstrated an anti-diabetic effect of TC via anti-oxidant and anti-inflammatory effects. The better effects of TC than CA suggesting that there is other effective compositions present in TC.