title: Anti-inflammatory, gastroprotective and anti-ulcerogenic effects of red algae Gracilaria changii (Gracilariales, Rhodophyta) extract.
abstract: BACKGROUND
  Gracilaria changii (Xia et Abbott) Abbott, Zhang et Xia, a red algae commonly found in the coastal areas of Malaysia is traditionally used for foods and for the treatment of various ailments including inflammation and gastric ailments. The aim of the study was to investigate anti-inflammatory, gastroprotective and anti-ulcerogenic activities of a mass spectrometry standardized methanolic extract of Gracilaria changii.
  
  
  METHODS
  Methanolic extract of Gracilaria changii (MeOHGCM6 extract) was prepared and standardized using mass spectrometry (MS). Anti-inflammatory activities of MeOHGCM6 extract were examined by treating U937 cells during its differentiation with 10 μg/ml MeOHGCM6 extract. Tumour necrosis factors-α (TNF-α) response level and TNF-α and interleukin-6 (IL-6) gene expression were monitored and compared to that treated by 10 nM betamethasone, an anti-inflammatory drug. Gastroprotective and anti-ulcerogenic activities of MeOHGCM6 extract were examined by feeding rats with MeOHGCM6 extract ranging from 2.5 to 500 mg/kg body weight (b.w.) following induction of gastric lesions. Production of mucus and gastric juice, pH of the gastric juice and non-protein sulfhydryls (NP-SH) levels were determined and compared to that fed by 20 mg/kg b.w. omeprazole (OMP), a known anti-ulcer drug.
  
  
  RESULTS
  MS/MS analysis of the MeOHGCM6 extracts revealed the presence of methyl 10-hydroxyphaeophorbide a and 10-hydroxypheophytin a, known chlorophyll proteins and several unidentified molecules. Treatment with 10 μg/ml MeOHGCM6 extract during differentiation of U937 cells significantly inhibited TNF-α response level and TNF-α and IL-6 gene expression. The inhibitory effect was comparable to that of betamethasone. No cytotoxic effects were recorded for cells treated with the 10 μg/ml MeOHGCM6 extract. Rats fed with MeOHGCM6 extract at 500 mg/kg b.w. showed reduced absolute ethanol-induced gastric lesion sizes by > 99% (p < 0.05). This protective effect was comparable to that conferred by OMP. The pH of the gastric mucus decreased in dose-dependent manner from 5.51 to 3.82 and there was a significant increase in NP-SH concentrations.
  
  
  CONCLUSIONS
  Results from the study, suggest that the mass spectrometry standardized methanolic extract of Gracillaria changii possesses anti-inflammatory, gastroprotective and anti-ulcerogenic properties. Further examination of the active constituent of the extract and its mechanism of action is warranted in the future.
authors.affiliation: Tropical Infectious Diseases Research and Education Center (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
authors.forename: Meng-Hooi
authors.initials: MH
authors.lastname: Shu
authors.forename: David
authors.initials: D
authors.lastname: Appleton
authors.forename: Keivan
authors.initials: K
authors.lastname: Zandi
authors.forename: Sazaly
authors.initials: S
authors.lastname: AbuBakar
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000032:analysis / Q000494:pharmacology / Q000627:therapeutic use*; D000897:Anti-Ulcer Agents / Q000032:analysis / Q000494:pharmacology / Q000627:therapeutic use*; D001623:Betamethasone / Q000494:pharmacology; D045744:Cell Line, Tumor; D002734:Chlorophyll / Q000032:analysis / Q000494:pharmacology / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005260:Female; D005750:Gastric Juice / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D044724:Gracilaria / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control*; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D009093:Mucus / Q000378:metabolism; D009853:Omeprazole / Q000494:pharmacology; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D013270:Stomach / Q000187:drug effects* / Q000473:pathology; D013276:Stomach Ulcer / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D000897:Anti-Ulcer Agents; D015850:Interleukin-6; D010936:Plant Extracts; D013438:Sulfhydryl Compounds; D014409:Tumor Necrosis Factor-alpha; C406457:phaeophytin a; D002734:Chlorophyll; D001623:Betamethasone; D009853:Omeprazole