(200-01) Anti-oxidation and anti-diabetic properties of green and yellow papaya (Carica papaya): Stimulation of glucose uptake in liver and myoblasts and wound healing in fibroblast.
Body of Abstract: According to recent statistics, 37.3 million Americans had diabetes in 2019. Its prevalence was highest among African Americans and American-Indians/Alaskan Natives. The objective of the present research was to evaluate green and yellow papaya for anti-oxidation and anti-diabetic properties. Leaves, skin, pulp, and seed extracts from green and yellow papaya were prepared in water or 80% methanol. Total polyphenols were determined using Folin-Ciocalteu method. The anti-oxidation activity was measured by DPPH and FRAP methods. Glucose uptake in liver was assayed using an NBD-glucose analogue. The Glut-2 expression was quantified by ELISA. The triglyceride was measured by an enzymatic assay and wound healing activity was analyzed using microscopy. The methanol or water extracts of green and yellow papaya contained similar concentrations of polyphenols in skin, leaf, and pulp. However, methanol and water extracts of seeds from yellow papaya have higher concentrations of polyphenols compared to green papaya. Both water and methanol extracts of yellow papaya exhibited higher anti-oxidation activity in skin, pulp, and seeds. Old leaves also showed greater antioxidation activity compared to new leaves. Pulp extracts from yellow and green papaya stimulated greater glucose uptake in liver and muscle cells. Similarly, pulp extract stimulated Glut-2 and Glut-4 expression in liver cells and myoblasts, respectively. The skin, pulp, and seeds of green or yellow papaya showed triglyceride-lowering activity in liver cells but yellow papaya had a more potent effect. Seeds from both green and yellow papaya significantly stimulated migration of fibroblast in the wounded area. Further, seeds from both green and yellow papaya also significantly stimulated collagen synthesis in fibroblast cells by almost 3-fold. In conclusion, papaya produced stimulatory effects on glucose uptake, Glut-2/Glut-4 expression, TG reduction and wound-healing activities. This study concludes that different parts of the papaya can be beneficial for preventing diabetes and diabetes-related wound healing (NIFA-USDA-2018-38821-27756).