title: In Vitro antioxidative activity of pumpkin seed (Cucurbita pepo) protein isolate and its In Vivo effect on alanine transaminase and aspartate transaminase in acetaminophen-induced liver injury in low protein fed rats.
abstract: The antioxidative effects of pumpkin seed protein isolate (Cucurbita pepo) were investigated in vitro. The isolate exhibited about 80% radical scavenging activity, chelating activity of approximately 64% on Fe2+ ions and an inhibition of approximately 10% of xanthine oxidase. Subsequently the effects of the isolate on the plasma activity levels of alanine transaminase and aspartate transaminase against acetaminophen induced acute liver injury in low-protein fed male Sprague-Dawley rats were ascertained. The rats were maintained on a low-protein diet for 5 days and divided into three subgroups. Two subgroups were injected with acetaminophen and the other with an equivalent amount of polyethylene glycol 400. Two hours after intoxication one of the two subgroups was administered with the protein isolate. Rats from the different subgroups were killed at 24, 48 and 72 h after treatment. After 5 days on the low-protein diet the activity levels of the enzymes were significantly higher than their counterparts on a normal balanced diet. The administration of protein isolate after acetaminophen intoxication resulted in significantly reduced activity levels. It is concluded that the protein isolate has promising antioxidative properties. Furthermore, the isolate administration was effective in alleviating the detrimental effects associated with protein malnutrition and acetaminophen intoxication.
authors.affiliation: Department of Biochemistry and Microbiology, University of Zululand, Private Bag X1001, KwaDlangezwa, South Africa.
authors.forename: C Z
authors.initials: CZ
authors.lastname: Nkosi
authors.forename: A R
authors.initials: AR
authors.lastname: Opoku
authors.forename: S E
authors.initials: SE
authors.lastname: Terblanche
mesh_terms: D000410:Alanine Transaminase / Q000187:drug effects; D000818:Animals; D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D001219:Aspartate Aminotransferases / Q000187:drug effects; D028464:Cucurbita / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis; D006520:Hepatitis, Animal / Q000201:enzymology; D007502:Iron Chelating Agents / Q000032:analysis; D008297:Male; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D059808:Polyphenols; D011488:Protein Deficiency / Q000201:enzymology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012639:Seeds / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000032:analysis; D000637:Transaminases / Q000187:drug effects*; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D007502:Iron Chelating Agents; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D013438:Sulfhydryl Compounds; D014969:Xanthine Oxidase; D000637:Transaminases; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase