Moringa oleifera leaves, seeds, pods, roots, and flowers have been widely used for their medicinal and nutritional properties. Many studies have been conducted on the chemical composition and effectiveness of M. oleifera. In fact, almost every part of M. oleifera has been found to contain essential nutrients and medicinal value. Especially, the leaves of M. oleifera are known to have various nutrients and diverse efficacy. Several studies have assessed the potential toxicity of the leaves when prepared by various methods. The results showed that the M. oleifera leaves when prepared differently were safe in locally used doses and amounts. Moreover, M. oleifera is known to contain various physiological efficacies, including antioxidant, anti-inflammatory, antidiabetic, and anticancer effects and so on. In the latest research, many attempts are being made to utilize the diverse effects of M. oleifera. This research seems to be bringing a promising view of M. oleifera as a therapeutic functional food for various diseases.

Metabolic syndrome, including obesity, glucose intolerance and elevated blood pressure, is related to type 2 diabetes and cardiovascular disease. Previous studies have reported the anti-oxidative, anti-inflammatory and anti-diabetic effects of purple corn extract. We investigated the efficacy of purple corn extract (PC) against high-fat diet (HFD)-induced obesity and glucose intolerance, and examined the underlying mechanisms by analyzing expression of proteins and genes involved in glucose regulation and macrophage infiltration. C57BL/6 mice were fed with normal chow diet (ND), or HFD treated with distilled water (DW, control) or PC, for 10 weeks. Although body weights were similar in the HFD-fed groups, we observed a decrease in the liver and epididymal adipose tissue (EAT) weights, and enhanced glucose tolerance test (GTT) results in the PC group, as compared with DW group. Liver showed increased Akt phosphorylation in the PC-treated mice; however, no changes were observed in the EAT, for all groups. In PC-treated mice, decreased macrophage infiltration was seen in the EAT, with a reduced expression of macrophage marker genes. Finally, proinflammatory cytokine gene expressions were decreased by PC in the EAT, and a modest trend for downregulation was observed in the liver. Hence, we conclude that PC may decrease glucose intolerance by increasing the phosphorylation of Akt and reducing the macrophage infiltration into the EAT.