| Abstract: | 糖尿病(Diabetes)的主因是胰島β細胞受到氧化逆境傷害，伴隨著β細胞死亡, 因而無法產生足夠胰島素，體內代謝異常繼而產生胰島素阻抗，相互作用下惡性循環。文獻研究報告指出花青素(Anthocyanins, ANT) 對於改善血糖與血脂代謝異常有顯著功效，在於花青素優異的抗炎與抗氧化能力。
因此，本實驗以小鼠進行動物試驗並分為三組: 控制組(Control), 實驗控制組(STZ-control) 和花青素實驗組(STZ-ANT)。兩個實驗組以腹腔注射150 mg/kg鏈脲佐菌素(Streptozotocin , STZ)誘發小鼠高血糖症狀，STZ-ANT組連續28天口管餵食花青素150 mg/kg，本實驗使用的花青素萃取來自台灣台東縣源天然農業有限公司所生產的黑纖米TM (Black indica riceTM)。
空腹血糖在實驗28天後STZ-ANT組低於STZ-control組具有極顯著性差異p<0.01，STZ-ANT組的空腹血糖實驗前後，具有極顯著性差異p<0.01，STZ-control組實驗前後則是無顯著性差異p>0.05。
西方墨點法檢驗小鼠肝臟細胞發現，葡萄糖轉運蛋白4(GLUT4)的表達STZ-ANT組高於STZ-control組1.3倍，具有極顯著性差異p<0.01；證明黑纖米TM花青素(Black indica riceTM ANT, BANT) 增加胰島素接受器GLUT4的敏感性。
腫瘤壞死因子α (TNFα)通過信號轉導會阻礙胰島素介導脂解作用；實驗結果發現STZ-ANT組TNFα的表達低於STZ-control組具有極顯著差異p<0.01，抑制37%的TNFα因子激活，證明黑纖米TM花青素抑制炎症作用。
最後，過氧化物酶體增殖物活化受體γ (Peroxisome proliferator- activated receptor γ, PPARγ)主要在腸和脂肪組織中表達,並且促進脂質儲存和脂肪特異性基因的表達，觸發脂肪細胞分化的主要致脂肪因子，也是肥胖型糖尿病產生胰島素阻抗的關鍵。TNFα路徑與NF-κB訊號的活化都會抑制PPARγ表達，實驗結果發現STZ-ANT組的PPARγ表達高於STZ-Control組具有極顯著性差異p<0.01，證明了黑纖米TM花青素抑制炎症介質TNFα的阻礙，提升胰島素敏感性，加強了胰島素脂肪酸脂肪分解作用。
綜合以上，可以見到在使用黑纖米TM萃取物花青素的STZ-ANT組別，發現有顯著性差異下調炎症因子的表達，從而達到增加胰島素敏感性、抗發炎、降低氧化逆境，降低血糖與發炎症狀的實驗結果。希望藉由本次黑纖米TM花青素(BANT)的實驗基礎，未來投入臨床應用，研發出預防與治療糖尿病的健康食品。
Oxidative stress is the main cause of Diabetes due to damage beta cells of pancreas, along with the inability of beta cells to produce enough insulin, metabolic abnormalities in the body and subsequent insulin resistance, and a vicious circle of interaction. Literature studies reported that anthocyanins (ANT) has a significant effect on improving blood glucose and lipid metabolism, mainly due to its excellent anti-inflammatory and anti-oxidant.
Therefore, the experiment was carried out in mice and divided into three groups: a control group (control group), an experimental control group (STZ-control group), and an anthocyanin experimental group (STZ-ANT). In both experimental groups, hyperglycemia was induced by intraperitoneal injection of 150 mg / kg streptozotocin (STZ). The STZ-ANT group was fed anthocyanin 150 mg / kg for 28 consecutive days. The anthocyanins used in this experiment were extract from Black indica riceTM which are produce by Origin Aguriculture Co. Ltd. in Taitung County Taiwan(R.O.C.).
The blood glucose level in the STZ-ANT group was very significantly lower than the STZ-control group after experiment p<0.01. There was a very significant difference between the STZ-ANT group before and after the fasting blood glucose test p<0.01. The STZ-control group there is no significant difference p>0.05. The Western blot analysis of mouse liver cells revealed that GLUT4 expression in the STZ-ANT group was 1.3 times higher than in the STZ-control group, with a very significant difference of p<0.01; evidence of Black indica riceTM anthocyanins (BANT) increases the sensitivity of the insulin receptor GLUT4.
Tumor necrosis factor alpha (TNFα) blocked insulin-mediated lipolysis by signal transduction; the results showed that the expression of TNFα in STZ-ANT group was significantly lower than that in STZ control group p <0.01, and the inhibition rate of TNFα factor was 37%. It is proved that Black indica riceTM anthocyanins can inhibit inflammation.
Finally, peroxisome proliferator-activated receptor γ (PPARγ) is mainly expressed in the intestine and adipose tissue and promotes the storage of lipids and the expression of fat-specific genes, triggering the main cause of adipocyte differentiation. Adipokines, the key to insulin resistance in obese diabetics. The activation of TNFα pathway and NF-κB signals both inhibited the expression of PPARγ, the results showed that a very significant of STZ-ANT group higher than STZ-Control group p<0.01, to proved the inhibition of inflammatory mediator TNFα through the Black indica riceTM anthocyanin, improve insulin sensitivity, and enhance the lipolysis of fatty acids.
In conclusion, we can see a significant difference in down-regulation of inflammatory molecules in the STZ-ANT group, which can increase insulin sensitivity, anti-inflammatory and reduce oxidative stress. The use of Black indica riceTM anthocyanin (BANT) in this study resulted in reduced hyperglycemia and inflammation. We hope to use this experimental basis to develop healthy foods of BANT to prevent and treat diabetes. |
