The physicochemical and biopharmaceutical properties of fragmented keratin as a new drug carrier

Safety Assessment of Keratin and Keratin-Derived Ingredients as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 8 keratin-derived ingredients, which function mainly as skin and hair conditioning agents in personal care products. The Panel reviewed relevant data provided in this safety assessment and concluded that the 8 keratin-derived ingredients are safe in the present practices of use and concentration described in this safety assessment.

Xijiao Dihuang Decoction () and Rehmannia glutinosa Libosch. protect mice against lipopolysaccharide and tumor necrosis factor alpha-induced acute liver failure

OBJECTIVE

To investigate the hepatoprotective effect of Xijiao Dihuang Decoction (, XJDHD) on lipopolysaccharide (LPS)- and tumor necrosis factor alpha (TNF-α)-induced acute liver failure (ALF) as well as the underlying mechanism of action, and to clarify the key herbs and components of XJDHD.

METHODS

LPS/D-galactosamine (D-GalN) or TNF-α/D-GalN were intraperitoneally injected into C57BL/6J mice to induce ALF. Simultaneously, XJDHD or its individual herbs and components were orally administered. Survival rates, transaminase levels in serum, and hepatic histology were examined to evaluate the effects of XJDHD. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and real-time polymerase chain reaction were additionally performed to expound the mechanism underlying the anti-apoptotic activity of XJDHD.

RESULTS

Oral administration of XJDHD protected mice from lethal liver failure induced by LPS and TNF-α, with notable amelioration of liver injury in histology and a significant decrease in transaminase levels in serum. XJDHD significantly inhibited apoptosis of hepatocytes and enhanced expression of the antiapoptosis genes, c-Flip, Iap1, Gadd45b and A20. In addition, Rehmannia glutinosa Libosch. was identified as the key herb of XJDHD and galactose as the effective component of Rehmannia glutinosa Libosch. that protects against ALF.

CONCLUSIONS

XJDHD inhibits TNF-α-induced apoptosis of hepatocytes by promoting the expression of nuclear factor κ B-regulated anti-apoptotic genes. Rehmannia glutinosa Libosch. is the effective herb of XJDHD and galactose is an active component in this protection.

Clinical and nutritional benefits of cysteine-enriched protein supplements

PURPOSE OF REVIEW

To review recently published research into the use of dietary cysteine and/or its derivatives as functional food supplements that will enhance antioxidant status and improve outcome in certain diseases.

RECENT FINDINGS

L-cysteine is now widely recognized as a conditionally essential or (indispensible) sulphur amino acid. It plays a key role in the metabolic pathways involving methionine, taurine and glutathione (GSH), and may help fight chronic inflammation by boosting antioxidant status. In stressed and inflammatory states, sulphur amino acid metabolism adapts to meet the increased requirements for cysteine as a rate-limiting substrate for GSH. Critically ill patients receiving enteral or parenteral nutrition, enriched with cysteine, exhibit decreased cysteine catabolism and improved GSH synthesis. The naturally occurring cysteine-rich proteins, whey or keratin, have the potential to be manufactured into high quality, high cysteine-containing functional foods for clinical investigation.

SUMMARY

Cysteine-rich proteins, such as keratin, may have advantages over the simple amino acid or its derivatives, as nutraceuticals, to safely and beneficially improve antioxidant status in health and disease.