title: Whey Protein Hydrolysate but not Whole Whey Protein Protects Against 7,12-Dimethylbenz(a)anthracene-Induced Mammary Tumors in Rats.
abstract: Effects of intact and processed bovine milk proteins on development of chemically induced mammary tumors in female rats were compared. AIN-93G diets were made with 20% casein (CAS), casein hydrolysate (CASH), intact whey protein (IWP), or whey protein hydrolysate (WPH). Pregnant Sprague-Dawley rats were fed the diets starting at Gestational Day 4. Offspring were fed the same diet. At 50 days, female offspring (44-49/group) were gavaged with sesame oil containing 80 mg/kg of the mammary carcinogen dimethylbenzanthracene (DMBA) and euthanized 62 days posttreatment. Rats fed WPH had an adenocarcinoma incidence of 17% compared to the rats fed CAS, CASH, and IWP diets (34%, 33%, and 36% respectively) (P < 0.001). Median palpable tumor latency for rats fed WPH was greater (61 days, P < 0.001) compared to CAS (44 days), CASH (42 days) and IWP (45 days). Tumor multiplicity was also lower (1.5 vs. 3.0, P < 0.05) in rats fed WPH than in CAS and CASH fed groups. Results demonstrate that hydrolytic processing of whey protein is required for this diet to be effective in reducing DMBA-induced mammary tumors. The bioactive compounds produced during whey protein processing and mechanisms underlying the anticancer effects of WPH are yet to be identified.
authors.affiliation: a Arkansas Children's Nutrition Center and Departments of Pediatrics and Pharmacology & Toxicology , University of Arkansas , Little Rock , Arkansas , USA.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Ronis
authors.forename: Reza
authors.initials: R
authors.lastname: Hakkak
authors.forename: Soheila
authors.initials: S
authors.lastname: Korourian
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Badger
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene / Q000633:toxicity*; D000818:Animals; D002273:Carcinogens / Q000633:toxicity; D002364:Caseins / Q000494:pharmacology; D004032:Diet; D004195:Disease Models, Animal; D005260:Female; D015674:Mammary Neoplasms, Animal / Q000139:chemically induced / Q000188:drug therapy*; D011247:Pregnancy; D020011:Protective Agents / Q000494:pharmacology; D011492:Protein Hydrolysates / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000067816:Whey Proteins / Q000494:pharmacology*
chemical_list: D002273:Carcinogens; D002364:Caseins; D020011:Protective Agents; D011492:Protein Hydrolysates; D000067816:Whey Proteins; D015127:9,10-Dimethyl-1,2-benzanthracene; C475729:casein hydrolysate