title: Multiple cellular effects of leaf extracts from Parinari curatellifolia.
abstract: BACKGROUND
  Parinari curatellifolia is a prominent plant in folk medicine in Sub-Saharan Africa. The plant decoctions are used to treat various ailments, including the treatment of cancer, pneumonia, fever, microbial infections and anti-inflammation. The aims of the study were to investigate the effects of P. curatellifolia leaf extracts on cell inflammatory and proliferative activity.
  
  
  METHODS
  Parinari curatellifolia fresh leaves were collected from Centenary in Mashonaland Central Province of Zimbabwe. Plant extracts were prepared using methanol, water, acetone and ethanol. Firstly, the effects of the extracts were determined on xanthine oxidase activity. Kinetic constants were determined for the extracts that showed inhibitory effects. Then the effects of Parinari curatellifolia water extract on LPS, menadione and hydrogen peroxide-activated nitric oxide production in RAW 264.7 cells was determined by quantifying the amount of nitrites formed. Finally, the effects of P. curatellifolia on the proliferation of Jurkat-T cells as well as its modulation of cisplatin-induced cell- cytotoxicity was investigated on a Jurkat human T-cell lymphoma cell line.
  
  
  RESULTS
  There was significant XO inhibitory activity by the ethanol and methanol extracts at 15.6 μg/ml and 3.9 μg/ml respectively. The IC50 determination for allopurinol, ethanol extract and methanol extract were 0.43 μg/ml, 1.38 μg/ml and 2.19 μg/ml respectively. The kinetic results showed that the ethanol and methanol extracts were allosteric inhibitors of XO. The water extract of P. curatellifolia inhibited NO production in RAW cells when LPS was used as an activator. P. curatellifolia and cisplatin showed dose-dependent cytotoxicity on Jurkat-T cells. Isolated DNA from the cells showed that there was DNA cleavage on cells exposed to P. curatellifolia indicating that apoptosis may be a mechanism by which P. curatellifolia exerts its cytotoxicity on Jurkat-T cells.
  
  
  CONCLUSIONS
  These results scientifically support the use of P. curatellifolia leaf extracts in the management of pain, inflammatory and neoplastic conditions. P. curatellifolia thus has multiple biological effects, thus, validating its use in traditional medical uses.
authors.affiliation: School of Pharmacy, College of Health Sciences, University of Zimbabwe, Mt. Pleasant, Harare, Zimbabwe.
authors.forename: Mitchelle
authors.initials: M
authors.lastname: Gororo
authors.affiliation: Department of Biochemistry, University of Zimbabwe, Mt. Pleasant, Harare, Zimbabwe.
authors.forename: Theresa
authors.initials: T
authors.lastname: Chimponda
authors.affiliation: Department of Biochemistry, University of Zimbabwe, Mt. Pleasant, Harare, Zimbabwe.
authors.forename: Elaine
authors.initials: E
authors.lastname: Chirisa
authors.affiliation: Department of Biochemistry, University of Zimbabwe, Mt. Pleasant, Harare, Zimbabwe. smukanganyama@medic.uz.ac.zw.|Bio-molecular Interactions Analyses Group, Department of Biochemistry, University of Zimbabwe, P.O. Box MP 167, Mt. Pleasant, Harare, Zimbabwe. smukanganyama@medic.uz.ac.zw.
authors.forename: Stanley
authors.initials: S
authors.lastname: Mukanganyama
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects*; D045469:Chrysobalanaceae / Q000737:chemistry*; D006801:Humans; D019169:Jurkat Cells; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry*; D020011:Protective Agents / Q000737:chemistry / Q000494:pharmacology*; D000067996:RAW 264.7 Cells; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: D010936:Plant Extracts; D020011:Protective Agents; D009569:Nitric Oxide; D014969:Xanthine Oxidase
keywords: Apoptosis; Gout; Jurkat T cells; Nitric oxide production; Parinari curatellifolia; RAW 264.7 murine macrophages; Xanthine oxidase