Trivalent chromium (Cr) and bitter melon (Momordica charantia L., BM) have been shown to independently interact with the insulin signaling pathway leading to improvements in the symptoms of insulin resistance and diabetes in some animal models and human subjects. The aim of this study was to examine whether the combination of the two nutritional supplements could potentially have additive effects on treating these conditions in high-fat-fed streptozotocin (STZ)-induced diabetic rats. The experiment was conducted with 110 male Wistar rats divided into eleven groups and fed either a control or high-fat diet for 7 weeks. Half of the rats on the high-fat diet were injected with STZ (30 mg/kg body mass) to induce diabetes. The high-fat (HF) diets were then supplemented with a combination of Cr (as chromium(III) propionate complex, Cr3: either 10 or 50 mg Cr/kg diet) and bitter melon (lyophilized whole fruit: either 10 or 50 g/kg diet) for 6 weeks. After termination of the experiment, blood and internal organs were harvested for blood biochemical, hematological, and mineral (Cr) analyses using appropriate analytical methods. It was found that neither Cr(III) nor BM was able to significantly affect blood indices in HF and diabetic rats, but BM tended to improve body mass gain, blood glucose, and LDL cholesterol values, but decreased Cr content in the liver and kidneys of the Cr-co-supplemented type 2 diabetic model of rats. Supplementary Cr(III) had no appreciable effect on glucose and lipid metabolism in high-fat-fed STZ-induced diabetic rats. Supplementary BM fruit powder had some observable effects on body mass of high-fat-fed rats; these effects seem to be dampened when BM was co-administered with Cr. Cr(III) and BM appear to act as nutritional antagonists when both administered in food, probably due to binding of Cr by the polyphenol-type compounds present in the plant material.

Graphical Abstract

三价铬（Cr）和苦瓜（苦瓜L.，BM）已经显示出独立地与胰岛素信号传导途径相互作用，从而导致在某些动物模型和人类受试者中胰岛素抵抗和糖尿病的症状得到改善。这项研究的目的是检查两种营养补品的组合是否可能对高脂链脲佐菌素（STZ）诱导的糖尿病大鼠在治疗这些疾病上具有加性作用。实验是将110只雄性Wistar大鼠分为11组，并以对照或高脂饮食喂养7周。高脂饮食的一半大鼠被注射STZ（30 mg / kg体重）以诱发糖尿病。然后在高脂（HF）饮食中补充Cr（作为丙酸铬（III）复合物，Cr3：10或50 mg Cr / kg饮食）和苦瓜（冻干的整个水果：10或50 g / kg饮食）持续6周。实验终止后，使用适当的分析方法采集血液和内脏进行血液生化，血液学和矿物质（Cr）分析。结果发现，Cr（III）和BM均不能显着影响HF和糖尿病大鼠的血液指标，但是BM倾向于改善体重增加，血糖和LDL胆固醇值，但降低了肝脏和肾脏中的Cr含量Cr共补充的2型糖尿病模型的建立。补充Cr（III）对高脂喂养的STZ诱导的糖尿病大鼠的葡萄糖和脂质代谢没有明显影响。补充BM水果粉对高脂饮食大鼠的体重有一些可观察到的影响。当BM与Cr并用时，这些作用似乎会减弱。

图形概要