title: Ocimum gratissimum L. leaf flavonoid-rich fraction suppress LPS-induced inflammatory response in RAW 264.7 macrophages and peritonitis in mice.
abstract: BACKGROUND
  Ocimum gratissimum L. is a herbaceous plant that has been reported in several ethnopharmacological surveys as a plant readily accessible to the communities and widely used for the treatment of inflammatory diseases. The main goal of this study was to investigate the in vitro and in vivo anti-inflammatory activity and mechanism of action of the ethylacetate fraction of O. gratissimum leaf (EAFOg) and to chemically characterize this fraction.
  
  
  METHODS
  EAFOg was obtained from a sequential methanol extract. The safety profile was evaluated on RAW 264.7 cells, using the alamarBlue® assay. Phenolic contents were determined by spectrophotometry, and metabolites quantified by high performance liquid chromatography. The anti-inflammatory activity of EAFOg and its ability to acts on leucocytes infiltration, inflammatory mediators as NO, IL-1β, TNF-α, and IL-10 in lipopolysaccharide-induced peritonitis in mice and LPS-stimulated RAW 264.7 macrophage were evaluated. In addition, the anti-inflammatory activity of EAFOg was also investigated in arachidonic acid-related enzymes.
  
  
  RESULTS
  Total phenolic and flavonoid contents of EAFOg were 139.76±1.07mg GAE/g and 109.95±0.05mg RE/g respectively. HPLC analysis revealed the presence of rutin, ellagic acid, myricetin and morin. The fraction exhibited no cytotoxic effects on the RAW 264.7 cells. The EAFOg (10, 50 and 200mg/kg) significantly reduced (p<0.05) neutrophils (38.8%, 58.9%, and 66.5%) and monocytes (38.9%, 58.0% and 72.8%) in LPS-induced peritonitis. Also, EAFOg (5, 20 and 100µg/mL) produced significant reduction in NO, IL-1β, and TNF-α in RAW 264.7 cells. However, IL-10 level was not affected by the EAFOg, and it preferentially inhibits COX-2 (IC50=48.86±0.02µg/mL) than COX-1 and 15-LO (IC50>100µg/mL).
  
  
  CONCLUSIONS
  The flavonoid-rich fraction of O. gratissimum leaves demonstrated anti-inflammatory activity via mechanisms that involves inhibition of leucocytes influx, NO, IL-1β, and TNF-α in vivo and in vitro, thus supporting its therapeutic potential in slowing down inflammatory processes in chronic diseases.
authors.affiliation: Department of Basic Health Sciences, Faculty of Medicine, Federal University of Mato Grosso (UFMT), Av. Fernando Correa da Costa, no. 2367, Coxipó, Boa Esperança, Cuiabá 78060-900, Mato Grosso, Brazil; Natural Products Research Laboratory, Faculty of Medicine, Federal University of Tocantins (UFT), Av. NS15, Palmas 77020-210, Tocantins, Brazil.
authors.forename: Abayomi Mayowa
authors.initials: AM
authors.lastname: Ajayi
authors.affiliation: Department of Basic Health Sciences, Faculty of Medicine, Federal University of Mato Grosso (UFMT), Av. Fernando Correa da Costa, no. 2367, Coxipó, Boa Esperança, Cuiabá 78060-900, Mato Grosso, Brazil.
authors.forename: Domingos Tabajara de Oliveira
authors.initials: DTO
authors.lastname: Martins
authors.affiliation: Department of Basic Health Sciences, Faculty of Medicine, Federal University of Mato Grosso (UFMT), Av. Fernando Correa da Costa, no. 2367, Coxipó, Boa Esperança, Cuiabá 78060-900, Mato Grosso, Brazil; Curso da Farmácia, AJES, Faculdades de Vale do Juruena. Avenida Gabriel Müller, s/n AJES - Módulo I, 78320-000, Juína Mato Grosso, Brazil.
authors.forename: Sikiru Olaitan
authors.initials: SO
authors.lastname: Balogun
authors.affiliation: Department of Basic Health Sciences, Faculty of Medicine, Federal University of Mato Grosso (UFMT), Av. Fernando Correa da Costa, no. 2367, Coxipó, Boa Esperança, Cuiabá 78060-900, Mato Grosso, Brazil.
authors.forename: Ruberlei Godinho de
authors.initials: RG
authors.lastname: Oliveira
authors.affiliation: Natural Products Research Laboratory, Faculty of Medicine, Federal University of Tocantins (UFT), Av. NS15, Palmas 77020-210, Tocantins, Brazil.
authors.forename: Sérgio Donizeti
authors.initials: SD
authors.lastname: Ascêncio
authors.affiliation: Natural Products Research Laboratory, Faculty of Medicine, Federal University of Tocantins (UFT), Av. NS15, Palmas 77020-210, Tocantins, Brazil.
authors.forename: Ilsamar Mendes
authors.initials: IM
authors.lastname: Soares
authors.affiliation: Natural Products Research Laboratory, Faculty of Medicine, Federal University of Tocantins (UFT), Av. NS15, Palmas 77020-210, Tocantins, Brazil.
authors.forename: Robson Dos Santos
authors.initials: RDS
authors.lastname: Barbosa
authors.affiliation: Department of Pharmacology & Therapeutics, Faculty of Basic Medical Sciences, College of Medicine, University of Ibadan, Oyo - State, Nigeria. Electronic address: ademowo_g@yahoo.com.
authors.forename: Olusegun George
authors.initials: OG
authors.lastname: Ademowo
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D001202:Ascitic Fluid / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D051545:Cyclooxygenase 1 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D005260:Female; D008070:Lipopolysaccharides; D008264:Macrophages / Q000187:drug effects; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D031339:Ocimum; D010533:Peritoneal Lavage; D010538:Peritonitis / Q000188:drug therapy / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use*; D018515:Plant Leaves; D000067996:RAW 264.7 Cells
chemical_list: D000893:Anti-Inflammatory Agents; D016207:Cytokines; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D010936:Plant Extracts; D009569:Nitric Oxide; C077623:Ptgs2 protein, mouse; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496512:Ptgs1 protein, mouse
keywords: Flavonoid; In vitro; In vivo; Inflammation; Phenolic compounds