title: Inhibition of Platelet Aggregation by the Leaf Extract of Carica papaya During Dengue Infection: An In Vitro Study.
abstract: Dengue cases were reported to undergo platelet activation and thrombocytopenia by a poorly understood mechanism. Recent studies suggested that Carica papaya leaf extract could recover the platelet count in dengue cases. However, no studies have attempted to unravel the mechanism of the plant extract in platelet recovery. Since there are no available drugs to treat dengue and considering the significance of C. papaya in dengue treatment, the current study aimed to evaluate two research questions: First one is to study if the C. papaya leaf extract exerts its action directly on platelets and second one is to understand if the extract can specifically inhibit the platelet aggregation during dengue viral infection. Sixty subjects with dengue positive and 60 healthy subjects were recruited in the study. Platelet-rich plasma (PRP) and platelet-poor plasma were prepared from both the dengue-infected and healthy control blood samples. Effect of the leaf extract obtained from C. papaya leaves was assessed on plasma obtained as well as platelets collected from both healthy and dengue-infected individuals. Platelet aggregation was significantly reduced when leaf extract preincubated with dengue plasma was added into control PRP, whereas no change in aggregation when leaf extract incubated-control plasma was added into control PRP. Upon direct addition of C. papaya leaf extract, both dengue PRP and control PRP showed a significant reduction in platelet aggregation. Within the dengue group, PRP from severe and nonsevere cases showed a significant decrease in aggregation without any difference between them. From the study, it is evident that C. papaya leaf extract can directly act on platelet. The present study, the first of its kind, found that the leaf extract possesses a dengue-specific neutralizing effect on dengue viral-infected plasma that may exert a protective role on platelets.
authors.affiliation: 1 Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER) , Puducherry, India .
authors.forename: Shobia
authors.initials: S
authors.lastname: Chinnappan
authors.affiliation: 1 Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER) , Puducherry, India .
authors.forename: Vijayakumar Shettikothanuru
authors.initials: VS
authors.lastname: Ramachandrappa
authors.affiliation: 2 Department of Medicine, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER) , Puducherry, India .
authors.forename: Kadhiravan
authors.initials: K
authors.lastname: Tamilarasu
authors.affiliation: 3 School of Chemical and Biotechnology, SASTRA University , Thanjavur, India .
authors.forename: Uma Maheswari
authors.initials: UM
authors.lastname: Krishnan
authors.affiliation: 3 School of Chemical and Biotechnology, SASTRA University , Thanjavur, India .|4 Central Inter-Disciplinary Research Facility (CIDRF) , A Unit of Sri Balaji Educational and Charitable Public Trust, Puducherry, India .
authors.forename: Agiesh Kumar Balakrishna
authors.initials: AK
authors.lastname: Pillai
authors.affiliation: 1 Department of Biochemistry, Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER) , Puducherry, India .
authors.forename: Soundravally
authors.initials: S
authors.lastname: Rajendiran
mesh_terms: D001792:Blood Platelets / Q000187:drug effects*; D029441:Carica / Q000378:metabolism*; D003715:Dengue / Q000188:drug therapy; D003716:Dengue Virus / Q000472:pathogenicity; D006801:Humans; D007194:India; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000378:metabolism*; D015539:Platelet Activation / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D013921:Thrombocytopenia / Q000188:drug therapy
chemical_list: D010936:Plant Extracts; D010975:Platelet Aggregation Inhibitors