title: Phenolic compounds from sandpaper (ficus exasperata) leaf inhibits angiotensin 1 converting enzyme in high cholesterol diet fed rats.
abstract: BACKGROUND
  Sandpaper [Ficus exasperata Vahl (Moraceae)] leaf has been reportedly used in folklore for the management/treatment of cardiovascular diseases with little/or no scientific basis for their action. This study sought to investigate the effect of dietary supplementation of sandpaper leaf on angiotensin-I converting enzyme (ACE) activity in hypercholesterolemia as well as the effect of their phenolic extract on this enzyme in vitro.
  
  
  METHODS
  The phenolic extract was prepared, then, the inhibitory effect of the leaf extract on ACE was determined in vitro. Thereafter, the effect of dietary supplementation of sandpaper leaf on angiotensin-I converting enzyme (ACE) activity in high cholesterol diet fed rats for 14 days was evaluated as well as some biochemical parameters.
  
  
  RESULTS
  The result revealed that under in vitro condition, the phenolic extract inhibited ACE (IC50=14.7µg/mL) in a dose-dependent manner (0-10µg/mL). Feeding high cholesterol diets to rats caused a significant (P<0.05) increase in the ACE activity. However, there was a significant (P<0.05) decrease in the ACE activity as a result of supplementation with the sand paper leaves. Furthermore, there was a significant (P<0.05) increase in the plasma lipid profile with a concomitant increase in malondialdehyde (MDA) content in rat liver and heart tissues. However, supplementing the diet with sandpaper leaf (either 10% or 20%) caused a significant (P<0.05) decrease in the plasma total cholesterol (TC), triglyceride (TG), very low density lipoprotein-cholesterol (VLDL-C), and low-density lipoprotein-cholesterol levels (LDL-C), and in MDA content in the tissues. Conversely, supplementation caused a significant (P<0.05) increase in plasma high-density lipoprotein-cholesterol level when compared with the control diet. Reversed phase HPLC analysis of the extract revealed Quercitrin (43.7mg/g), chlorogenic acid (42.8mg/g) and caffeic acid (33.9mg/g) as the major phenolics in the leaf.
  
  
  CONCLUSIONS
  The inhibition of ACE activity and prevention of hypercholesterolemia by sandpaper leaf could be part of the possible mechanism underlying its anti-hypertensive property which could lay credence to its use in folk medicine. However, these activities may be directly/indirectly attributed to the polyphenolics present.
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology Akure, P.M.B. 704, Akure 340001, Nigeria. Electronic address: goboh2001@yahoo.com.
authors.forename: G
authors.initials: G
authors.lastname: Oboh
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology Akure, P.M.B. 704, Akure 340001, Nigeria; Department of Biochemistry, Afe Babalola University Ado-Ekiti, P.M.B. 5454, Nigeria.
authors.forename: A J
authors.initials: AJ
authors.lastname: Akinyemi
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology Akure, P.M.B. 704, Akure 340001, Nigeria.
authors.forename: F R
authors.initials: FR
authors.lastname: Osanyinlusi
authors.affiliation: Functional Foods and Nutraceuticals Unit, Department of Biochemistry, Federal University of Technology Akure, P.M.B. 704, Akure 340001, Nigeria.
authors.forename: A O
authors.initials: AO
authors.lastname: Ademiluyi
authors.affiliation: Departamento de Quimica, Universidade Federal de Santa Maria (UFSM), Campus Universitário, Camobi 97105-900, Santa Maria RS, Brazil.
authors.forename: A A
authors.initials: AA
authors.lastname: Boligon
authors.affiliation: Departamento de Quimica, Universidade Federal de Santa Maria (UFSM), Campus Universitário, Camobi 97105-900, Santa Maria RS, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Athayde
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D030681:Ficus / Q000737:chemistry; D006937:Hypercholesterolemia / Q000188:drug therapy*; D020128:Inhibitory Concentration 50; D008055:Lipids / Q000097:blood; D008519:Medicine, Traditional; D007703:Peptidyl-Dipeptidase A / Q000187:drug effects; D010636:Phenols / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D018515:Plant Leaves; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D002791:Cholesterol, Dietary; D008055:Lipids; D010636:Phenols; D010936:Plant Extracts; D007703:Peptidyl-Dipeptidase A
keywords: ACE; Hypercholesterolemia; Phenolics; Sandpaper leaf