A method for examination of L-carnosine， eyeseryl，glutathione and acetyl hexapeptide-8 in cosmetics by HPLC / 上海预防医学

［ Objective:To establish a HPLC method for examination of L-carnosine，eyeseryl，glutathione and acetyl hexapeptide-8 in cosmetics. Method:After being extracted by water， L-carnosine， Eyeseryl， Glutathione， and Acetyl Hexapeptide-8 were examined by HPLC with methanol-0.01% formic acid （V/V） aqueous solution as the mobile phase. The column was Agilent Eclipse XDB-C18 （5 μm， 4.6 mm×150 mm）. The flow rate was 0.5 mL/min. The determination wavelength was set at 210 nm. Results:There was a good linear relationship within the range of 5-100 μg/mL for L-carnosine， eyeseryl， glutathione， and acetyl hexapeptide-8. The recoveries of L-carnosine Eyeseryl Glutathione and Acetyl Hexapeptide-8 were between 92.5%~105.9%， with a RSD from 0.5% to 3.5%. Conclusion:The method is simple， sensitive， specific and reproducible in the examination of L-carnosine， Eyeseryl， Glutathione， and Acetyl Hexapeptide-8 in cosmetics.

Acetyl hexapeptide-3 in a cosmetic formulation acts on skin mechanical properties - clinical study

abstract Acetyl hexapeptide-3 has been used in anti-aging topical formulations aimed at improving skin appearance. However, few basic studies address its effects on epidermis and dermis, when vehiculated in topical formulations. Thus, the objective of this study was to determine the clinical efficacy of acetyl hexapeptide-3 using biophysical techniques. For this purpose, formulations with and without acetyl hexapeptide-3 were applied to the ventral forearm and the face area of forty female volunteers. Skin conditions were evaluated after 2 and 4-week long daily applications, by analyzing the stratum corneum water content and the skin mechanical properties, using three instruments, the Corneometer(r) CM 825, CutometerSEM 575 and ReviscometerRV600. All formulations tested increased the stratum corneum water content in the face region, which remained constant until the end of the study. In contrast, only formulations containing acetyl hexapeptide-3 exhibit a significant effect on mechanical properties, by decreasing the anisotropy of the face skin. No significant effects were observed in viscoelasticity parameters. In conclusion, the effects of acetyl hexapeptide-3 on the anisotropy of face skin characterize the compound as an effective ingredient for improving conditions of the cutaneous tissue, when used in anti-aging cosmetic formulations.

resumo Acetil hexapeptídeo-3 tem sido utilizado como um ingrediente ativo em formulações tópicas antienvelhecimento para a melhoria da aparência cutânea. No entanto, poucos estudos avaliam seus efeitos na epiderme e derme, quando veiculado em formulações tópicas. Portanto, o objetivo desse estudo foi a determinação da eficácia clínica de acetil hexapeptídeo-3 utilizando técnicas de biofísica e de análise de imagem. Para tal, formulações contendo, ou não, acetil hexapeptídeo-3 foram aplicadas no antebraço volar e na face de voluntárias. As condições cutâneas foram avaliadas após duas e quatro semanas de aplicação diária das formulações, por meio da análise no conteúdo aquoso do estrato córneo e avaliação das propriedades mecânicas da pele, utilizando os equipamentos Corneometer(r) CM 825, CutometerSEM 575 e ReviscometerRV600. Todas as formulações avaliadas aumentaram o conteúdo aquoso do estrato córneo na face, o qual permaneceu constante até o fim do estudo. Por outro lado, somente as formulações contendo acetil hexapeptídeo-3 apresentaram efeito significativo nas propriedades mecânicas, por meio da diminuição da anisotropia da pele na face. Não foram observados efeitos significativos para os parâmetros de viscoelasticidade. Em conclusão, os efeitos de acetil hexapeptídeo-3 na pele caracteriza este peptídeo como um ingrediente ativo efetivo para a melhoria das condições cutâneas, quando utilizadas em formulações cosméticas.

Effects of Growth Hormone Releasing Hexapeptide(GHRP-6) on Rat Anterior Pituitary Cell Culture / 대한소아내분비학회지

PURPOSE: GH-releasing peptide(GHRP-6) was shown to possess strong GH-releasing activity both in vitro and in vivo. Chemically,GHRP-6 has no primary sequence homology with GHRH. The GH releasing activity of GHRP-6 has been demonstrated in several animal species including humans. GHRPs could have a considerable physiological and clinical useful for treatment of GH deficient and/or non GH deficient short children in the near future. The aim of this study was to evaluate the GH-releasing activity of GHRP-6 in anterior pituitary cell culture and compared to that of GHRH . METHODS: Spraque-Dawley rats were decapitated and pituitary glands were collected in ice-cold PBS. The anterior pituitaries were minced into small fragments and dissociated by enzymatic digestion. These pituitary cells were suspended in Dulbecco' modified Eagle' medium(DMEM) with fetal calf serum at a concentration of 106cells/mL and then plated onto multiwelled dishes at a density of 1.5*05 cells per 6 well plate. GHRP-6 treated group(10-8, 10-7, 10-6 M), GHRH treated group(10-8, 10-7, 10-6 M) and combined GHRP-6 and GHRH treated group were classified. After replacement of each GHRP and/or GHRH+GHRP, the released GH were measured with RIA in 10 min, 20 min, and 30 min. RESULTS: 1) GHRH(10-8) treatment increased GH release by 15.8+/-3.9ng/mL in 0 min., 69.8+/-4.3ng/mL in 10 min. 78.3+/-5.0ng/mL in 20 min. and 67.8+/-7.2ng/mL in 30 min. In case of GHRP-6(10-8M) treatment increased GH release by 11.0+/-1.4 in 0 min., 90.3+/-12.2 in 10 min., 78.3+/-4.5ng/mL in 20 min. and 78.0+/-4.8ng/mL in 30 min. The released GH levels were markedly increased in 10 min. after GHRP-6 and were not singificantly different from that of GHRH. 2)GHRP+GHRH(10-7M+10-8M) treatment increase GH release by 8.8+/-1.5ng/mL in 0 min., 37.8+/-9.3ng/mL in 10 min., 41.3+/-8.1ng/mL in 20 min. and 40.0+/-7.9ng/mL in 30 min. The released GH levels after GHRP+GHRH treatment was not markedly increased statistically compared to GHRH only. CONCLUSION: GHRP-6 could release GH in rat anterior pituitary cell culture and the released GH amounts were not significantly different from that of GHRH. There was no synergistic additive effect in GHRP+GHRH in rat pituitary cell culture.

Interaction of two LAC repressor protein segments with polynucleotides.

The interaction of the oligopeptides Ala-Gln-GIn-Leu-Ala-Gly-OH and Gln-Leu- Ala-Gly-OMe corresponding, respectively, to the sequence 53–58 and 55–58 of lac repressor protein with four polynucleotides was studied. The two peptides did not interact with poly dA. poly dT, poly d(A-T).poly d(A-T) or poly d(A-G).poly d(C-T). But they interacted in a characteristic way with poly d(A-C). poly d (G-T), the sequences of which are in abundance in the lac operator region. Both the peptides stabilised the melting of poly d (A-C). poly d (G-T) at a peptide to nucleotide ratio (P/N) of 4; at lower ratios, they destabilised the DNA slightly. The circular dichroism of the alternating polynucleotide with CAC/GTG sequences was perturbed by both the oligopeptides. The hexapeptide at a P/N of 4 caused the transformation of the Bform circular dichroism spectrum to a new state, characterised by strong 220 and 240 nm bands, and a rather weak long wavelength spectrum.