An Insight into the Changes in Skin Texture and Properties following Dietary Intervention with a Nutricosmeceutical Containing a Blend of Collagen Bioactive Peptides and Antioxidants.

BACKGROUND: Skin aging is a multifactorial phenomenon which causes alterations in skin physiological functions and, most visibly, phenotypic changes. In particular, during the aging process, hyaluronic acid, collagen, and elastin fibers undergo structural and functional changes. AIMS: This study aimed to give an insight into the photo-protective benefits and efficacy of an oral liquid nutricosmeceutical containing collagen bioactive peptides and antioxidants to counteract the signs of aging. METHODS: A double-blind, randomized, placebo-controlled clinical trial was conducted by an independent esthetic clinic on 120 healthy volunteer subjects for 90 days. Subjects were divided into 2 groups: 60 subjects consumed 1 bottle (50 mL) of the nutricosmeceutical daily and the other 60 consumed 1 bottle (50 mL) of the placebo. Outcome measures were related to skin elasticity (expressed as Young's elasticity modulus) and skin architecture (histological analysis). In addition, the subjects recruited in this study underwent observational assessments through self-assessment questionnaires. RESULTS AND CONCLUSIONS: Overall, we demonstrated a significant increase in skin elasticity (+7.5%), p ≤ 0.001 and an improvement in skin texture after daily oral consumption of the nutricosmeceutical. We also obtained a positive patient feedback through the self-assessment questionnaires. Taken together these results show that this nutricosmeceutical supplement may have photo-protective effects and help improve skin health.

Nucleolar localization and circadian regulation of Per2S, a novel splicing variant of the Period 2 gene.

In this work, we show for the first time that a second splicing variant of the core clock gene Period 2 (Per2), Per2S, is expressed at both the mRNA and protein levels in human keratinocytes and that it localizes in the nucleoli. Moreover, we show that a reversible perturbation of the nucleolar structure acts as a resetting stimulus for the cellular clock. Per2S expression and periodic oscillation upon dexamethasone treatment were assessed by qRT-PCR using specific primers. Western blot (WB) analysis using an antibody against the recombinant human PER2 (abRc) displayed an intense band at a molecular weight of ~55 kDa, close to the predicted size of Per2S, and a weaker band at the expected size of Per2 (~140 kDa). The antibody raised against PER2 pS662 (abS662), an epitope absent in PER2S, detected only the higher band. Immunolocalization studies with abRc revealed a peculiar nucleolar signal colocalizing with the nucleolar marker nucleophosmin, whereas with abS662 the signal was predominantly diffuse all over the nucleus and partially colocalized with abRc in the nucleolus. The analysis of cell fractions by WB confirmed the enrichment of PER2S and the presence of PER2 in the nucleolar compartment. Finally, a pulse (1 h) of actinomycin D (0.01 µg/ml) induced reversible nucleolar disruption, PER2S de-localization and circadian synchronization of clock and Per2S genes. Our work represents the first evidence that the Per2S splicing isoform is a clock component expressed in human cells localizing in the nucleolus. These results suggest a critical role for the nucleolus in the process of circadian synchronization in human keratinocytes.

Effects of collagen-derived bioactive peptides and natural antioxidant compounds on proliferation and matrix protein synthesis by cultured normal human dermal fibroblasts.

Nutraceuticals containing collagen peptides, vitamins, minerals and antioxidants are innovative functional food supplements that have been clinically shown to have positive effects on skin hydration and elasticity in vivo. In this study, we investigated the interactions between collagen peptides (0.3-8 kDa) and other constituents present in liquid collagen-based nutraceuticals on normal primary dermal fibroblast function in a novel, physiologically relevant, cell culture model crowded with macromolecular dextran sulphate. Collagen peptides significantly increased fibroblast elastin synthesis, while significantly inhibiting release of MMP-1 and MMP-3 and elastin degradation. The positive effects of the collagen peptides on these responses and on fibroblast proliferation were enhanced in the presence of the antioxidant constituents of the products. These data provide a scientific, cell-based, rationale for the positive effects of these collagen-based nutraceutical supplements on skin properties, suggesting that enhanced formation of stable dermal fibroblast-derived extracellular matrices may follow their oral consumption.

Daily oral supplementation with collagen peptides combined with vitamins and other bioactive compounds improves skin elasticity and has a beneficial effect on joint and general wellbeing.

Aging is a multifactorial and natural process that causes physiological changes in organs, tissues and cells over time. In the skin and cartilage, aging leads to a decrease in the synthesis and changes in the arrangement of proteoglycans and collagen, in addition to the loss of glycosaminoglycans, which are responsible for the integrity and health of these tissues. We hypothesized that daily oral supplementation with a liquid nutraceutical containing hydrolyzed fish collagen, vitamins, antioxidants and other active ingredients could improve skin texture and elasticity, and in addition have a protective effect on joint health. A double-blind, randomized, placebo-controlled clinical trial was conducted on 120 subjects who consumed either the test product or placebo on a daily basis for 90 days. Subjects consuming the test product had an overall significant increase in skin elasticity (+40%; P < .0001) when compared to placebo. Histological analysis of skin biopsies revealed positive changes in the skin architecture, with a reduction in solar elastosis and improvement in collagen fiber organization in the test product group. As reported in the self-perception questionnaires, these results were confirmed by the subjects' own perceptions in that participants agreed their skin was more hydrated and more elastic. In addition, the consumption of the test product reduced joint pain by -43% and improved joint mobility by +39%. Oral supplementation with collagen bioactive peptides combined with chondroitin sulphate, glucosamine, L-carnitine, vitamins, and minerals significantly improved the clinical parameters related to skin aging and joint health, and therefore, might be an effective solution to slow down the hallmarks of aging.

Peroxiredoxin 2 nuclear levels are regulated by circadian clock synchronization in human keratinocytes.

Circadian rhythms are highly conserved time tracking systems regulating important biological processes at both systemic and cellular levels. The present study was aimed to identify proteins and biological functions circadian regulated in human keratinocytes. HaCaT keratinocytes were entrained by temperature cycles, and a proteomic study was performed on cell fractions isolated under free running conditions at constant temperature. Bioinformatics analysis revealed that molecular clock entrainment was associated with changes in molecular components regulating cell proliferation, energy metabolism, transcription, translation and redox balance. Nuclear levels of the antioxidant enzyme Peroxiredoxin 2 (PRDX2) were found to oscillate rhythmically over two entire 24h long cycles. Donwregulation of PRDX2 resulted in upregulation of the mitochondrion-specific Peroxiredoxin 3 (PRDX3), all other members of the Peroxiredoxin family remained unaltered. Furthermore, PRDX2 knockdown increased intracellular levels of reactive oxygen species (ROS) and impaired cell cycle progression and proliferation. HaCaT cells transduced with a scramble shRNA were used as control. Our work is the first to show that nuclear levels of PRDX2 display circadian oscillation participating in the regulation of human keratinocytes redox balance.