title: Correlation of antiangiogenic, antioxidant and cytotoxic activities of some Sudanese medicinal plants with phenolic and flavonoid contents.
abstract: BACKGROUND
  Consumption of medicinal plants to overcome diseases is traditionally belongs to the characteristics of most cultures on this earth. Sudan has been a host and cradle to various ancient civilizations and developed a vast knowledge on traditional medicinal plants. The present study was undertaken to evaluate the antioxidant, antiangiogenic and cytotoxic activities of six Sudanese medicinal plants which have been traditionally used to treat neoplasia. Further the biological activities were correlated with phytochemical contents of the plant extracts.
  
  
  METHODS
  Different parts of the plants were subjected to sequential extraction method. Cytotoxicity of the extracts was determined by dimethylthiazol-2-yl)- 2,5diphenyl tetrazolium bromide (MTT) assay on 2 human cancer (colon and breast) and normal (endothelial and colon fibroblast) cells. Anti-angiogenic potential was tested using ex vivo rat aortic ring assay. DPPH (1,1-diphenyl-2-picrylhydrazyl) assay was conducted to screen the antioxidant capabilities of the extracts. Finally, total phenolic and flavonoid contents were estimated in the extracts using colorimetric assays.
  
  
  RESULTS
  The results indicated that out of 6 plants tested, 4 plants (Nicotiana glauca, Tephrosia apollinea, Combretum hartmannianum and Tamarix nilotica) exhibited remarkable anti-angiogenic activity by inhibiting the sprouting of microvessels more than 60%. However, the most potent antiangiogenic effect was recorded by ethanol extract of T. apollinea (94.62%). In addition, the plants exhibited significant antiproliferative effects against human breast (MCF-7) and colon (HCT 116) cancer cells while being non-cytotoxic to the tested normal cells. The IC50 values determined for C. hartmannianum, N. gluaca and T. apollinea against MCF-7 cells were 8.48, 10.78 and 29.36 μg/ml, respectively. Whereas, the IC50 values estimated for N. gluaca, T. apollinea and C. hartmannianum against HCT 116 cells were 5.4, 20.2 and 27.2 μg/ml, respectively. These results were more or less equal to the standard reference drugs, tamoxifen (IC50 = 6.67 μg/ml) and 5-fluorouracil (IC50 = 3.9 μg/ml) tested against MCF-7 and HCT 116, respectively. Extracts of C. hartmannianum bark and N. glauca leaves demonstrated potent antioxidant effect with IC50s range from 9.4-22.4 and 13.4-30 μg/ml, respectively. Extracts of N. glauca leaves and T apollinea aerial parts demonstrated high amount of flavonoids range from 57.6-88.1 and 10.7-78 mg quercetin equivalent/g, respectively.
  
  
  CONCLUSIONS
  These results are in good agreement with the ethnobotanical uses of the plants (N. glauca, T. apollinea, C. hartmannianum and T. nilotica) to cure the oxidative stress and paraneoplastic symptoms caused by the cancer. These findings endorse further investigations on these plants to determine the active principles and their mode of action.
authors.forename: Loiy Elsir A
authors.initials: LE
authors.lastname: Hassan
authors.forename: Mohamed B Khadeer
authors.initials: MB
authors.lastname: Ahamed
authors.forename: Aman S Abdul
authors.initials: AS
authors.lastname: Majid
authors.forename: Hussein M
authors.initials: HM
authors.lastname: Baharetha
authors.forename: Nahdzatul S
authors.initials: NS
authors.lastname: Muslim
authors.forename: Zeyad D
authors.initials: ZD
authors.lastname: Nassar
authors.affiliation: EMAN Research and Testing Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia. aminmalikshah@gmail.com.
authors.forename: Amin M S Abdul
authors.initials: AM
authors.lastname: Majid
mesh_terms: D020533:Angiogenesis Inhibitors / Q000032:analysis / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D001011:Aorta / Q000187:drug effects; D001713:Biphenyl Compounds; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D029765:Combretum / Q000737:chemistry; D005419:Flavonoids / Q000032:analysis / Q000494:pharmacology*; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D010636:Phenols / Q000032:analysis / Q000494:pharmacology*; D010936:Plant Extracts / Q000032:analysis / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013397:Sudan; D032363:Tamaricaceae / Q000737:chemistry; D031304:Tephrosia / Q000737:chemistry; D014026:Nicotiana / Q000737:chemistry
chemical_list: D020533:Angiogenesis Inhibitors; D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; C010574:biphenyl