title: Protective effect of gallic acid and Syzygium cumini extract against oxidative stress-induced cellular injury in human lymphocytes.
abstract: BACKGROUND
  Syzygium cumini (Myrtaceae) presents antioxidant, anti-inflammatory, hypoglycemic and antibacterial effects; however, the cellular and molecular mechanisms of action in the immune system are not yet completely elucidated.
  
  
  OBJECTIVE
  This study evaluates the in vitro effect of gallic acid and aqueous S. cumini leaf extract (ASc) on adenosine deaminase (ADA) and dipeptidyl peptidase IV (DPP-IV) activities, cell viability and oxidative stress parameters in lymphocytes exposed to 2, 2'-azobis-2-amidinopropane dihydrochloride (AAPH).
  
  
  METHODS
  Lymphocytes were incubated with ASc (100 and 500 µg/ml) and gallic acid (50 and 200 µM) at 37 °C for 30 min followed by incubation with AAPH (1 mM) at 37 °C for 2 h. After the incubation time, the lymphocytes were used for determinations of ADA, DPP-IV and lactate dehydrogenase (LDH) activities, lipid peroxidation, protein thiol (P-SH) group levels and cellular viability by colorimetric methods.
  
  
  RESULTS
  (i) HPLC fingerprinting of ASc revealed the presence of catechin, epicatechin, rutin, quercitrin, isoquercitrin, quercetin, kaempferol and chlorogenic, caffeic, gallic and ellagic acids; (ii) for the first time, ASc reduced the AAPH-induced increase in ADA activity, but no effect was observed on DPP-IV activity; (iii) ASc increased P-SH groups and cellular viability and decreased LDH activity, but was not able to reduce the AAPH-induced lipid peroxidation; (iv) gallic acid showed less protective effects than ASc.
  
  
  CONCLUSIONS
  ASc affects the purinergic system and may modulate adenosine levels, indicating that the extract of this plant exhibits immunomodulatory properties. ASc also may potentially prevent the cellular injury induced by oxidative stress, highlighting its cytoprotective effects.
authors.affiliation: a Postgraduate Program in Pharmacology, Department of Clinical and Toxicology Analysis, Center of Health Sciences, Federal University of Santa Maria (UFSM) , Santa Maria , RS , Brazil .
authors.forename: Karine Santos
authors.initials: KS
authors.lastname: De Bona
authors.affiliation: a Postgraduate Program in Pharmacology, Department of Clinical and Toxicology Analysis, Center of Health Sciences, Federal University of Santa Maria (UFSM) , Santa Maria , RS , Brazil .
authors.forename: Gabriela
authors.initials: G
authors.lastname: Bonfanti
authors.affiliation: b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Paula Eliete Rodrigues
authors.initials: PE
authors.lastname: Bitencourt
authors.affiliation: b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Thainan Paz
authors.initials: TP
authors.lastname: da Silva
authors.affiliation: b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Raphaela Maleski
authors.initials: RM
authors.lastname: Borges
authors.affiliation: b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Aline
authors.initials: A
authors.lastname: Boligon
authors.affiliation: c Franciscan University Center, UNIFRA , Santa Maria , RS , Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Pigatto
authors.affiliation: b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Margareth Lynde
authors.initials: ML
authors.lastname: Athayde
authors.affiliation: a Postgraduate Program in Pharmacology, Department of Clinical and Toxicology Analysis, Center of Health Sciences, Federal University of Santa Maria (UFSM) , Santa Maria , RS , Brazil .|b Postgraduate Program in Pharmaceutical Sciences, UFSM , Santa Maria , Brazil , and.
authors.forename: Maria Beatriz
authors.initials: MB
authors.lastname: Moretto
mesh_terms: D000578:Amidines / Q000494:pharmacology; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D005707:Gallic Acid / Q000494:pharmacology*; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects* / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D027842:Syzygium / Q000737:chemistry*
chemical_list: D000578:Amidines; D000975:Antioxidants; D010936:Plant Extracts; D005707:Gallic Acid; C046728:2,2'-azobis(2-amidinopropane)
keywords: Adenosine deaminase; cellular viability; dipeptidyl peptidase IV; lactate dehydrogenase; lipid peroxidation; plant extract