Dried or fresh ground leaves are used to prepare papaya leaf extract which contain beneficial compounds such as flavonoids and other plant phenols, and alkaloids such as saponins, carpaine, anthraquinone, and cardiac glycosides including tannins and carposide. The compounds found within papaya leaf extract make it a rich source for antioxidant and free radical scavenging activity and RBC membrane stability, and papaya leaf extract may have a protective role against hemolysis in stressful conditions.
Bone marrow is suppressed by the dengue virus via circulating interleukin levels that are produced by activated immune cells inducing low platelet counts. Drawing nutrition from macrophages, monocytes, and endothelial cells the dengue virus will typically gravitate towards them and as a result focal apoptosis and necrosis may occur which can lead to platelet aggregation, platelet peripheral destruction, and infection. Vascular permeability increases due to proinflammatory factors as complement activation is a result of the inflammatory cascade.
Papaya leaf extract has been shown to help neutralize plasma containing dengue virus and significantly decrease platelet aggregation. ALOX12 has been shown to be increased by 15 times, the enzyme promotes platelet production via increased numbers and differentiation of megakaryocytes. PTAFR gene which is platelet specific is increased 13.5 fold following extract administration. Serine protease NS3 and NS2B are key to dengue virus replication are inhibited by quercetin which is one of the flavonoids in papaya leaves which prevent viral assembly which in one study was associated with platelet count rise in 24 hours as was total WBC count increased significantly.
With respect to disease and patient parameters poor reporting on part for most trials makes quality of available evidence low. Parameters design limitations an objective nature focused upon the platelet count, it is considered likely by researchers that the findings support further research into the significant beneficial properties of papaya leaf extract. Data needs to be measured and reported more appropriately before any definitive conclusions can be made.
