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harbonah
11-20-2012, 11:14 PM
Open-labeled pilot study of cysteine-rich whey protein isolate supplementation for nonalcoholic steatohepatitis patients.


Open-labeled pilot study of cysteine-rich whey protein isolate supplementation for nonalcoholic steatohepatitis patients.

Abstract
BACKGROUND AND AIMS:
Glutathione (GSH) depletion contributes to liver injury and development of steatohepatitis. Undenatured cysteine-rich whey protein isolate has been clinically proven to raise GSH in several patient groups. The aim of this study was to evaluate the effect of oral supplementation with whey protein on patients with nonalcoholic steatohepatitis (NASH).
METHODS:
In an open-labeled clinical trial, 38 patients (18 male, 20 female; mean age 48 +/- 14 years) with NASH confirmed by computed tomography measurements and liver biochemistries were given with a daily dose of 20 g whey protein isolate for 12 weeks.
RESULTS:
A significant reduction in alanine aminotransferase (ALT) (64 +/- 72 vs 46 +/- 36, P = 0.016) and aspartate aminotransferase (AST) (45 +/- 49 vs 33 +/- 18, P = 0.047) were observed. Plasma glutathione and total antioxidant capacity increased significantly at the end of study (53 +/- 11 vs 68 +/- 11, P < 0.05 and 1.26 +/- 0.10 vs 2.03 +/- 0.10, P < 0.05). Liver attenuation index improved from -13.4 +/- 11.1 to -9.7 +/- 13.1 (P = 0.048). Hepatic macrovesicular steatosis decreased significantly after 12 weeks of supplementation (33.82 +/- 12.82 vs 30.66 +/- 15.96, P = 0.046). Whey protein isolate was well tolerated. No serious adverse events were observed.
CONCLUSIONS:
The results indicate that oral supplementation of cysteine-rich whey protein isolate leads to improvements in liver biochemistries, increased plasma GSH, total antioxidant capacity and reduced hepatic macrovesicular steatosis in NASH patients. The results support the role of oxidative stress in the pathogenesis of this disease.





Open-labeled pilot study of cysteine-rich whey protein isolate supplementation for nonalcoholic steatohepatitis patients. (http://www.ncbi.nlm.nih.gov/pubmed/19638084)

harbonah
11-20-2012, 11:59 PM
Dose-dependent satiating effect of whey relative to casein or soy.



Dose-dependent satiating effect of whey relative to casein or soy.
Abstract
Dietary protein plays a role in body weight regulation, partly because of its effects on appetite. The objective was to compare the effects of high or normal casein-, soy-, or whey-protein breakfasts on appetite, specific hormones, amino acid responses and subsequent energy intake. Twenty-five healthy subjects (mean+/-SEMBMI:23.9+/-0.3 kg/m2; age:22+/-1 years) received standardized breakfasts: custards with either casein-, soy, or whey-protein with either 10/55/35 (normal) or 25/55/20 (high)En% protein/carbohydrate/fat in a randomized, single-blind design. Appetite profile (Visual Analogue Scales) and amino acid concentrations were determined for 4 h whereas plasma glucose, insulin, active Glucagon-like Peptide 1 (GLP-1), and active ghrelin concentrations were determined for 3 h; the sensitive moment for lunch was determined. Subjects returned for a second set of experiments and received the same breakfasts, ad lib lunch was offered 180 min later; energy intake (EI) was assessed. At 10En%, whey decreased hunger more than casein or soy (p <0.05), coinciding with higher leucine, lysine, tryptophan, isoleucine, and threonine responses (p<0.05). At 25En% there were no differences in appetite ratings. Whey triggered the strongest responses in concentrations of active GLP-1 (p<0.05) and insulin (p<0.05) compared with casein and/or soy. There were no differences in EI. In conclusion, differences in appetite ratings between different proteins appeared at a normal concentration; at 10En% whey-protein decreased hunger more than casein- or soy-protein. At 25En% whey-protein triggered stronger responses in hormone concentrations than casein- or soy-protein. The results suggest that a difference in appetite ratings between types of protein appears when certain amino acids are above and below particular threshold values.



Dose-dependent satiating effect of whey relative to casein or soy. (http://www.ncbi.nlm.nih.gov/pubmed/19385022)