The beneficial effect of cholesterol-lowering proteins and/or peptides derived from various dietary sources is continuously reported. A non-dietary protein from silk cocoon, sericin, has also demonstrated cholesterol-lowering activity. A sericin hydrolysate prepared by enzymatic hydrolysis was also expected to posses this effect. The present study was aimed at investigating the cholesterol-lowering effect of sericin peptides, so called "sericin-derived oligopeptides" (SDO) both in vivo and in vitro. The results showed that SDO at all three doses tested (10 mg kg day, 50 mg kg day, and 200 mg kg day) suppressed serum total and non-HDL cholesterol levels in rats fed a high-cholesterol diet. Triglyceride and HDL-cholesterol levels were not significantly changed among all groups. The fecal contents of bile acids and cholesterol did not differ among high-cholesterol fed rats. SDO dose-dependently reduced cholesterol solubility in lipid micelles, and inhibited cholesterol uptake in monolayer Caco-2 cells. SDO also effectively bound to all three types of bile salts including taurocholate, deoxytaurocholate, and glycodeoxycholate. Direct interaction with bile acids of SDO may disrupt micellar cholesterol solubility, and subsequently reduce the absorption of dietary cholesterol in intestines. Taking all data together, SDO or sericin peptides exhibit a beneficial effect on blood cholesterol levels and could be potentially used as a health-promoting dietary supplement or nutraceutical product.

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Objective: Artocarpuslakoocha Roxb. Is a traditional medical plant native to Southeast Asia and used as a dried aqueous extract so-called puaghaad. Its role (and its major ingredient, oxyresveratrol) as an antioxidant neuroprotectant were explored.Methods: Differentiated SH-SY5Y neuroblastoma cells in 96-well plates were challenged with 200 µM H2O2 for 4h and either Trolox (100 µM), oxyresveratrol (5-100 µM), or puaghaad (1.2-25 µg/ml) applied 2h before H2O2 or for 20 h after H2O2Results: Continuous presence of both H washout. Cell viability, mitochondrial function, intracellular ROS, and lipid peroxidation were assessed.2O 2 and antioxidant reduced mitochondrial function by ~50% but only by 30% with antioxidant. Sustained 24 h H2O2 showed no recoveries with antioxidants. Cell viability was modestly restored when antioxidants accompanied H2O2 for 4 h and both washed for another 20 h, but little recovery of mitochondrial function even though antioxidants removed ROS and prevent lipid peroxidation. Antioxidants added for 20 h after H2O2 Conclusion:These results show that mitochondrial protection was illusive, yet both tested compounds, puaghaad and oxyresveratrol, improved cell viability and especially ROS levels and lipid peroxidation. The potency oxyresveratrol on theredox-sensitive expression of antioxidant enzymes and its pharmacokinetics suggests that oral puaghaad could provide effective protection in transient neurodegenerative disease. marginally improve mitochondria and modestly restore cell viability, but lipid peroxidation was completely reversed.