Suitability of high-molecular-weight tissue-derived elastin polypeptides and their particles as cosmetic biomaterials.

We aimed to determine the coacervation properties of high-molecular-weight (HMW) tissue-derived elastin (TDE) and to examine the potential use of TDE particles as a cosmetic biomaterial. TDE solutions were filtered and divided into three fractions (1-3) according to the molecular weight of the elastin. The turbidity of fraction 2, which contained a large portion (58%) of HMW elastin polypeptides (>100 kDa), was measured under several pH values (3.0-11.0) and NaCl concentrations (0-1000 mM) to examine its coacervation ability. HMW TDE exhibited coacervation under the physiological conditions (temperature, pH, and NaCl concentration) of the skin surface. We performed inclusion and release experiments using three model chemicals with different molecular weights and measured the size and zeta potential of the fraction 3 particles to investigate the suitability of HMW elastin polypeptides. Fraction 3, which contained a larger portion (64%) of HMW elastin polypeptides, displayed a strong coacervation property at a phase transition temperature of 19.8 ± 0.1°C. The inclusion ratio of the model chemical Biebrich Scarlet (BS) with a molecular weight of <600 was approximately 92.1 ± 0.7%. The release profiles of BS from the particles linearly increased and reached a plateau after 15 days. Moreover, the average size of the particles with BS was 474.2 ± 24.6 nm. The low-molecular-weight (LMW) elastin peptides have moisturizing and whitening functions for the skin. We concluded that TDE, as a mixture of HMW polypeptides and LMW peptides, can potentially serve as a multifunctional and effective cosmetic biomaterial.

Factors Regulating or Regulated by Myogenic Regulatory Factors in Skeletal Muscle Stem Cells.

MyoD, Myf5, myogenin, and MRF4 (also known as Myf6 or herculin) are myogenic regulatory factors (MRFs). MRFs are regarded as master transcription factors that are upregulated during myogenesis and influence stem cells to differentiate into myogenic lineage cells. In this review, we summarize MRFs, their regulatory factors, such as TLE3, NF-κB, and MRF target genes, including non-myogenic genes such as taste receptors. Understanding the function of MRFs and the physiology or pathology of satellite cells will contribute to the development of cell therapy and drug discovery for muscle-related diseases.

Tumor necrosis factor alpha regulates myogenesis to inhibit differentiation and promote proliferation in satellite cells.

TNF-α and NF-κB signaling is involved in the wasting of skeletal muscle in various conditions, in addition to cancer cachexia. TNF-α and NF-κB signaling promotes the expression level of muscle RING finger protein 1, a ubiquitin ligase, causing muscle degradation. Several studies have indicated that of TNF-α and NF-κB signaling suppresses muscle differentiation by reducing the levels of MyoD protein. On the other hand, TNF-α and NF-κB is required for myoblast proliferation. Thus, the role of TNF-α and NF-κB signaling in the process of myogenesis and regeneration of skeletal muscle is not completely elucidated. Here, we reported that TNF-α reduced the width of single fibers of skeletal muscle in an organ culture model. TNF-α and p65 repressed the transactivation of MyoD and suppressed myoblast differentiation. In addition, TNF-α increased the number of satellite cells, and NF-κB signaling was promoted at the proliferation stage during skeletal muscle regeneration in vivo. TNF-α and NF-κB signaling regulate myogenesis to inhibit differentiation and promote proliferation in satellite cells.

Vignacyanidin Polyphenols Isolated from Vigna Angularis Bean Promote Osteoblast Differentiation.

BACKGROUND/AIM: An effective bone regenerative method needs to be established for the dental field. To identify a novel osteogenic factor for bone regeneration, we examined the effect of vignacyanidin (VIG) on osteoblastogenesis. MATERIALS AND METHODS: W20-17 cells, MC3T3-E1 cells, and primary cultured murine calvarial osteoblasts were used. Osteoblast differentiation was stimulated by ß-glycerophosphate, ascorbic acid, or bone morphogenetic protein (BMP)-4. Adipogenesis was induced using dexamethasone, 3-isobutyl-1-methylxanthine, insulin, and rosiglitazone. Differentiation or proliferation markers were determined using western blotting and/or the quantitative reverse transcription polymerase chain reaction. Adipogenic cells were visualized by Oil Red O staining. RESULTS: VIG treatment increased the expression of osteoblastic markers and alkaline phosphatase activity of osteoblast-lineage cells in a concentration-dependent manner. However, adipogenesis and cell proliferation were not affected by VIG. CONCLUSION: VIG treatment promoted osteoblast differentiation in osteoblast-lineage cells.

Daily Oral Administration of Protease-Treated Royal Jelly Protects Against Denervation-Induced Skeletal Muscle Atrophy.

Honeybees produce royal jelly (RJ) from their cephalic glands. Royal jelly is a source of nutrition for the queen honey bee throughout its lifespan and is also involved in fertility and longevity. Royal jelly has long been considered beneficial to human health. We recently observed that RJ delayed impairment of motor function during aging, affecting muscle fiber size. However, how RJ affects skeletal muscle metabolism and the functional component of RJ is as of yet unidentified. We demonstrate that feeding mice with RJ daily prevents a decrease in myofiber size following denervation without affecting total muscle weight. RJ did not affect atrophy-related genes but stimulated the expression of myogenesis-related genes, including IGF-1 and IGF receptor. Trans-10-hydroxy-2-decenoic acid (10H2DA) and 10-hydroxydecanoic acid (10HDAA), two major fatty acids contained in RJ. After ingestion, 10H2DA and 10HDAA are metabolized into 2-decenedioic acid (2DA) and sebacic acid (SA) respectively. We found that 10H2DA, 10HDAA, 2DA, and SA all regulated myogenesis of C2C12 cells, murine myoblast cells. These novel findings may be useful for potential preventative and therapeutic applications for muscle atrophy disease included in Sarcopenia, an age-related decline in skeletal muscle mass and strength.

Oral Administration of Geranylgeraniol Rescues Denervation-induced Muscle Atrophy via Suppression of Atrogin-1.

BACKGROUND/AIM: Geranylgeraniol (GGOH), a C20 isoprenoid naturally occurs in several foods. We previously reported that GGOH treatment reduced the expression levels of Atrogin-1 which is involved in skeletal muscle degradation and stimulates the myogenic differentiation of C2C12 myoblasts. However, the effect of GGOH supplementation on skeletal muscle metabolism in vivo is unknown. MATERIALS AND METHODS: Skeletal muscle atrophy was induced by denervation. The expression levels of Atrogin-1 were assessed by western blotting or real time PCR. RESULTS: Intraoral administration of GGOH reduced the decrease in the cross-sectional area of muscle fibers and also suppressed the expression levels of Atrogin-1 in denervation induced muscle atrophy. Also, GGOH treatment suppressed the expression of Atrogin-1 and the decrease in skeletal muscle fiber size by glucocorticoid in vitro. CONCLUSION: Intraoral administration of GGOH rescues denervation-induced muscle atrophy via suppression of Atrogin-1.

VNUT/SLC17A9, a vesicular nucleotide transporter, regulates osteoblast differentiation.

Osteoblasts release adenosine triphosphate (ATP) out of the cell following mechanical stress. Although it is well established that extracellular ATP affects bone metabolism via P2 receptors [such as purinergic receptor P2X7 (P2X7R) and purinergic receptor P2Y2 (P2Y2R)], the mechanism of ATP release from osteoblasts remains unknown. Recently, a vesicular nucleotide transporter [VNUT, solute carrier family 17 member 9 (SLC17A9)] that preserves ATP in vesicles has been identified. The purpose of this study was to elucidate the role of VNUT in osteoblast bone metabolism. mRNA and protein expression of VNUT were confirmed in mouse bone and in osteoblasts by quantitative real-time PCR (qPCR) and immunohistochemistry. Next, when compressive force was applied to MC3T3-E1 cells by centrifugation, the expression of Slc17a9, P2x7r, and P2y2r was increased concomitant with an increase in extracellular ATP levels. Furthermore, compressive force decreased the osteoblast differentiation capacity of MC3T3-E1 cells. shRNA knockdown of Slc17a9 in MC3T3-E1 cells reduced levels of extracellular ATP and also led to increased osteoblast differentiation after the application of compressive force as assessed by qPCR analysis of osteoblast markers such as Runx2, Osterix, and alkaline phosphatase (ALP) as well as ALP activity. Consistent with these observations, knockdown of P2x7r or P2y2r by siRNA partially rescued the downregulation of osteoblast differentiation markers, caused by mechanical loading. In conclusion, our results demonstrate that VNUT is expressed in osteoblasts and that VNUT inhibits osteoblast differentiation in response to compressive force by mechanisms related to ATP release and P2X7R and/or P2Y2R activity.

The Effect of Aromatherapy Treatment on Fatigue and Relaxation for Mothers during the Early Puerperal Period in Japan: A Pilot Study.

BACKGROUND: Early in the postpartum period, mothers are often nervous and tired from the delivery, breast-feeding and caring for a new-born. The aim of this study was to evaluate the process and outcome of using aromatherapy treatments to increase relaxation and decrease fatigue for mothers during the first to the seventh day of the postpartum period. METHODS: This non-randomized controlled study with a quasi-experimental one-group pretest-posttest design was used to evaluate scores in relaxation and fatigue before and after the intervention. Aromatherapy hand treatments were performed on a purposive sample of 34 postpartum mothers in Tokyo, Japan, from May to July 2016. The single treatment included a choice of one of five essential aroma oils through hand and forearm massage. Relaxation and fatigue were measured by self-administered valid and reliable questionnaires. Wilcoxon signed-rank test was conducted to analyze the data before and after the intervention. The software programs SPSS, v. 23.0 (SPSS, Tokyo), was used to analyze the data, with the significance level set at 5%. RESULTS: Valid responses were obtained from 29 participants. A comparison of the scores before and after aroma treatment intervention indicated that the participants' relaxation scores increased significantly (P<0.001) and fatigue scores were significantly reduced (P<0.001). The majority of participants (77.8%) were satisfied with the treatment. CONCLUSION: The aroma treatments significantly improved relaxation and reduced fatigue for mothers in the early puerperal period and were well received. Therefore, a larger study using a pretest-posttest random control trial is recommended.

Investigation of water-soluble elastin as a multifunctional cosmetic material: Moisturizing and whitening effects.

Elastin and collagen are extracellular matrix proteins that are widely distributed in the body. Although elastin essentially functions as a skin moisturizer, there have been few reports on its other fundamental chemical and biological functions. In this study, we investigated the moisturizing and whitening (tyrosinase inhibition) effects of elastin to examine its usefulness as a cosmetic material. Water-soluble hot alkali pig aorta (HAPA)-elastin was prepared from pig aorta using the hot alkali method. HAPA-elastin showed a widely distributed molecular weight and had a coacervation property that mediated reversible self-assembly of its molecules with increasing temperature. Amino acid analysis of HAPA-elastin showed a high content (81.5%) of hydrophobic amino acids such as Gly, Ala, Val, and Pro. Des (desmosine) and Ide (isodesmosine), which are characteristic amino acids of elastin, accounted for more than 0.4% of the total amino acid content. HAPA-elastin showed a moisture-retaining property. The water content of skin samples treated with and without HAPA-elastin was 77.2% ± 7.8% and 49.4% ± 10.1%, respectively. HAPA-elastin also inhibited tyrosinase activity by 11.3% ± 3.9%. The results obtained indicate that elastin has a useful function as a cosmetic material.

Design of Phenylalanine-Containing Elastin-Derived Peptides Exhibiting Highly Potent Self-Assembling Capability.

In this study, we developed a series of Phe-containing elastin-derived peptide-analogs, (Phe-Pro-Gly-Val-Gly)n (n = 1-5) and analyzed their reversible coacervation properties. Compared to the native elastin-derived repeating peptide sequence ((Val-Pro-Gly-Val-Gly)10), one of the Phecontaining 5-mer repeating peptide sequences ((Phe-Pro-Gly-Val-Gly)5) clearly exhibited stronger coacervation properties. The coacervation of (Phe-Pro-Gly-Val-Gly)5 is nearly the same as that of polypeptides (Val-Pro-Gly-Val-Gly)n (n > 40). Although large molecular weights (>10,000 Da) are generally required for the coacervation of elastin-derived peptides, (Phe-Pro-Gly-Val-Gly)5 exhibited reversible coacervation properties despite its low molecular weight (MW = 2,305 Da). High performance liquid chromatography (HPLC) and circular dichroism (CD) analysis revealed that (Phe-Pro-Gly-Val-Gly)5 has high hydrophobicity and an ordered structure with a type II ß-turn, which contributes to the strong coacervation ability of the peptide. In addition, (Phe-Pro-Gly-Val-Gly)5 exhibited an effective particle size distribution (60-70 nm) at body temperature (37°C) and a dispersed small particle size similar to that of the monomer peptides at low temperatures. These properties, along with its small size and simple design, render the peptide suitable for use in biomaterials, including drug-delivery carriers.