Ashwagandha Ethanol Extract Attenuates Sarcopenia-Related Muscle Atrophy in Aged Mice

The investigation focused on the impact of Withania somnifera (ashwagandha) extract (WSE) on age-related mechanisms affecting skeletal muscle sarcopenia-related muscle atrophy in aged mice. Beyond evaluating muscular aspects, the study explored chronic low-grade inflammation, muscle regeneration, and mitochondrial biogenesis. WSE administration, in comparison to the control group, demonstrated no significant differences in body weight, diet, or water intake, affirming its safety profile. Notably, WSE exhibited a propensity to reduce epidermal and abdominal fat while significantly increasing muscle mass at a dosage of 200 mg/kg. The muscle-to-fat ratio, adjusted for body weight, increased across all treatment groups. WSE administration led to a reduction in the pro-inflammatory cytokines TNF-α and IL-1β, mitigating inflammation-associated muscle atrophy. In a 12-month-old mouse model equivalent to a 50-year-old human, WSE effectively preserved muscle strength, stabilized grip strength, and increased muscle tissue weight. Positive effects were observed in running performance and endurance. Mechanistically, WSE balanced muscle protein synthesis/degradation, promoted fiber differentiation, and enhanced mitochondrial biogenesis through the IGF-1/Akt/mTOR pathway. This study provides compelling evidence for the anti-sarcopenic effects of WSE, positioning it as a promising candidate for preventing sarcopenia pending further clinical validation.

The efficacy and safety of Codonopsis lanceolata water extract for sarcopenia: A study protocol for randomized, double-blind, placebo-controlled clinical trial

INTRODUCTION

This study aimed to propose a protocol to demonstrate the efficacy of Codonopsis lanceolata water extract for the improvement of skeletal muscle mass (SMM) and function (muscle strength or performance function) and its safety compared to a placebo in adults with reduced muscle strength.

METHODS AND ANALYSIS

A randomized double-blind placebo-controlled clinical trial was conducted. Participants will be recruited from the Korean Medicine Hospital in South Korea. One hundred and four adults with reduced muscle strength will be randomly assigned a 1:1 ratio to either the experimental or placebo comparator groups. The participants will consume the product corresponding to their assigned group for the following 12 weeks, and efficacy and safety tests will be conducted. This is the first clinical trial of C lanceolata water extract in adults with reduced muscle strength. The results of this study would provide a clinical basis for the efficacy and safety of C lanceolata water extract in patients with sarcopenia.

ETHICS AND DISSEMINATION

This trial was approved by the Institutional Review Board (IRB) of Kyung Hee University Korean Medicine Hospital at Gangdong on July 15, 2021 (amendment number: MLB_DDE_H01 [ver. 01]). When a change was made in the clinical trial plan, the IRB reviewed and approved the revised clinical trial plan. The study was registered on the Clinical Research Information Service website on December 3, 2021 (registration number: PRE20211203-003; https://cris.nih.go.kr/cris/search/detailSearch.do?seq=20841&status=1&seq_group=20841&search_page=M). The results of this clinical trial will be reported in the future. Every document related to the clinical trial, such as the electronic case report form, will be recorded and classified by the subject identification code and not by the subject name.

Codonopsis lanceolata and its active component Tangshenoside I ameliorate skeletal muscle atrophy via regulating the PI3K/Akt and SIRT1/PGC-1α pathways

BACKGROUND

Skeletal muscle atrophy is caused by aging, disuse, malnutrition, and several diseases. However, there are still no effective drugs or treatments for muscle atrophy. Codonopsis lanceolata (CL), a traditional medicinal plant and food, has been reported to have anti-oxidative, anti-inflammatory, anti-tumor, and anti-obesity effects.

PURPOSE

This study aimed to investigate the efficacy and active component of CL on muscle atrophy in vitro and to confirm the effect of CL and its active component on muscle atrophy and the underlying molecular mechanisms in vivo.

STUDY

design/Methods This study used the dexamethasone (Dex)-induced muscle atrophy C2C12 myotube model and immobilization (IM)-induced muscle atrophy C57BL/6 mice model. In vitro study, the myotube diameter was measured. In vivo study, the grip strength, muscle mass (quadriceps, gastrocnemius, and soleus) and muscle fiber cross-sectional area (CSA) was measured. Western blot analysis and qRT-PCR were performed to confirm the underlying molecular mechanisms Results:In vitro study, CL and its main component, Tangshenoside I (TSI), effectively restored C2C12 myotube diameters decreased by Dex. Surprisingly, TSI was identified as the active component responsible for the overall efficacy of CL on muscle atrophy. In vivo study, CL and TSI, dose-dependently increased grip strength, mass muscle, and muscle fiber CSA reduced by IM. In the molecular mechanism studies, CL and TSI increased muscle protein synthesis via activating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin complex 1 (mTORC1) pathway and decreased muscle protein degradation via inhibiting the muscle ring finger-1 (MuRF1) and muscle atrophy F-box protein (Atrogin-1) expressions. It also upregulated mitochondrial biogenesis via the silent information regulator 1 (SIRT1)/ peroxisome proliferator-activated receptor gamma and coactivator-1 alpha (PGC-1α) pathway.

CONCLUSION

This study suggests that CL and its active component, TSI, can be potential drug candidates for the prevention and treatment of muscle atrophy.

The Administration of Panax Ginseng Berry Extract Attenuates High-Fat-Diet-Induced Sarcopenic Obesity in C57BL/6 Mice

Sarcopenia and obesity are serious health problems that are highly related to several metabolic diseases. Sarcopenic obesity, a combined state of sarcopenia and obesity, results in higher risks of metabolic diseases and even mortality than sarcopenia or obesity alone. Therefore, the development of therapeutic agents for sarcopenic obesity is crucial. C57BL/6 mice were fed with a high-fat diet (HFD) for 9 weeks. Then, mice were administered with Panax ginseng berry extract (GBE) for an additional 4 weeks, with continuous HFD intake. GBE significantly decreased the food efficiency ratio, serum lipid and insulin levels, adipose tissue weights, and adipocyte size. It significantly increased the grip strength, muscle masses, and myofiber cross-sectional area. It deactivated the protein kinase C (PKC) theta and zeta, resulting in activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway, which is known to regulate muscle synthesis and degradation. Furthermore, it inhibited the production of inflammatory cytokines in the muscle tissue. GBE attenuated both obesity and sarcopenia. Thus, GBE is a potential agent to prevent or treat sarcopenic obesity.

Codonopsis lanceolata ameliorates sarcopenic obesity via recovering PI3K/Akt pathway and lipid metabolism in skeletal muscle

BACKGROUND

The incidence of sarcopenic obesity, muscle atrophy induced by obesity, has steadily increased and is emerging as a health problem. Although the anti-obesity effect of Codonopsis lanceolata (CL) is known, its efficacy against sarcopenic obesity has not been studied.

PURPOSE

We aimed to investigate the effect of CL on sarcopenic obesity and the changes in the related mechanisms to confirm the potential of CL as an effective natural therapeutic agent for sarcopenic obesity.

METHODS

C57BL/6 mice were fed a high-fat diet (HFD) for 9 weeks, and CL was administered for 6 weeks with HFD feeding. Body weight and grip strength were measured twice a week. After sacrifice, muscle fiber histological analysis, blood lipid analysis, muscle triglyceride extraction, western blot, and real-time PCR were performed. High-performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS) analysis and in vitro experiments using C2C12 cells were performed to verify the main and active compounds of CL. Confluent C2C12 cells were differentiated for 4 days, and then the main compound of CL was co-treated with palmitic acid for 24 h.

RESULTS

CL reduced body weight, mass of three fat tissues (epididymal fat, mesenteric fat, and perirenal fat), adipocyte cross-sectional area (CSA), and improved insulin signaling. Simultaneously, CL improved grip strength, mass of three muscle tissues (quadriceps, gastrocnemius, and soleus), and muscle fiber CSA. These results were due to the recovery of both the phosphatidylinositol-3-kinase (PI3K)/ protein kinase B (Akt) signaling pathway and lipid metabolisms in skeletal muscle. Lipids accumulated in skeletal muscle interrupt the PI3K/Akt pathway, but CL reduced intramyocellular triglyceride concentration by restoring gene expression of factors related to triglyceride synthesis and fatty acid oxidation. Therefore, the activated PI3K/Akt pathway enhanced muscle protein synthesis by increasing phosphorylation of ribosomal protein S6 kinase 1 and eIF4E-binding protein 1 and suppressed muscle protein degradation by decreasing expression of muscle ring finger-1 and muscle atrophy F-box protein. In addition, tangshenoside I (TS) was verified as the main compound of CL by HPLC-ESI-MS analysis, and its efficacy of inhibiting myotube atrophy and lipid accumulation in myotubes was confirmed, verifying that TS is an active compound.

CONCLUSION

CL is an effective natural material for sarcopenic obesity that suppresses muscle atrophy by inhibiting the accumulation of lipids in skeletal muscle through restoration of impaired PI3K/Akt pathway and lipid metabolism.

Protective Effects of Spirulina maxima against Blue Light-Induced Retinal Damages in A2E-Laden ARPE-19 Cells and Balb/c Mice

Age-related macular degeneration (AMD) is a significant visual impairment in older people, and there is no treatment for dry AMD. Spirulina maxima (S. maxima), a cyanobacterium, has inhibitory effects against oxidative stress. However, the protective effects of S. maxima and its underlying mechanisms on blue light (BL)-caused macular degeneration are unknown. We aimed to investigate the protective effects of S. maxima on blue light-caused retinal damage and demonstrate its underlying mechanisms in human retinal pigment epithelial (ARPE-19) cells and Balb/c retinas. Additionally, the active component of S. maxima was examined in the RPE cells. In vitro, S. maxima decreased BL-induced RPE cell death by inhibiting reactive oxygen species (ROS) production. S. maxima inhibited BL-induced inflammation via regulating the NF-κB pathway, inflammatory-related gene expression, and the apoptosis pathway in RPE cells. In vivo, administration of S. maxima inhibited BL-induced retinal degeneration by restoring the thicknesses of whole retina, ONL (outer nuclear layer), INL (inner nuclear layer), and PL (photoreceptor layer) by BL exposure. Phycocyanin exerted protective effects in the pre-and post-treatment system. Therefore, S. maxima could be a potential nutraceutical approach to intercept the patho-physiological processes leading to dry AMD and advancement to wet AMD. Moreover, phycocyanin was a major active compound of S. maxima. These findings need to be investigated in human studies, particularly through a clinical trial.

Deacetylasperulosidic Acid Ameliorates Pruritus, Immune Imbalance, and Skin Barrier Dysfunction in 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis NC/Nga Mice

The prevalence of atopic dermatitis (AD), a disease characterized by severe pruritus, immune imbalance, and skin barrier dysfunction, is rapidly increasing worldwide. Deacetylasperulosidic acid (DAA) has anti-atopic activity in the three main cell types associated with AD: keratinocytes, mast cells, and eosinophils. Our study investigated the anti-atopic activity of DAA in 2,4-dinitrochlorobenzene-induced NC/Nga mice. DAA alleviated the symptoms of AD, including infiltration of inflammatory cells (mast cells and eosinophils), epidermal thickness, ear thickness, and scratching behavior. Furthermore, DAA reduced serum IgE, histamine, and IgG1/IgG2a ratio and modulated the levels of AD-related cytokines and chemokines, namely interleukin (IL)-1β, IL-4, IL-6, IL-9, IL-10, IL-12, tumor necrosis factor-α, interferon-γ, thymic stromal lymphopoietin, thymus and activation-regulated chemokine, macrophage-derived chemokine, and regulated on activation the normal T cell expressed and secreted in the serum. DAA restored immune balance by regulating gene expression and secretion of Th1-, Th2-, Th9-, Th17-, and Th22-mediated inflammatory factors in the dorsal skin and splenocytes and restored skin barrier function by increasing the expression of the pro-filaggrin gene and barrier-related proteins filaggrin, involucrin, and loricrin. These results suggest DAA as a potential therapeutic agent that can alleviate the symptoms of AD by reducing pruritus, modulating immune imbalance, and restoring skin barrier function.

Oyster Hydrolysates Attenuate Muscle Atrophy via Regulating Protein Turnover and Mitochondria Biogenesis in C2C12 Cell and Immobilized Mice

Sarcopenia, also known as skeletal muscle atrophy, is characterized by significant loss of muscle mass and strength. Oyster (Crassostrea gigas) hydrolysates have anti-cancer, antioxidant, and anti-inflammation properties. However, the anti-sarcopenic effect of oyster hydrolysates remains uninvestigated. Therefore, we prepared two different oyster hydrolysates, namely TGPN and PNY. This study aimed to determine the anti-muscle atrophy efficacy and molecular mechanisms of TGPN and PNY on both C2C12 cell lines and mice. In vitro, the TGPN and PNY recovered the dexamethasone-induced reduction in the myotube diameters. In vivo, TGPN and PNY administration not only improved grip strength and exercise endurance, but also attenuated the loss of muscle mass and muscle fiber cross-sectional area. Mechanistically, TGPN and PNY increased the expression of protein synthesis-related protein levels via phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of the rapamycin pathway, and reduced the expression of protein degradation-related protein levels via the PI3K/Akt/forkhead box O pathway. Also, TGPN and PNY stimulated NAD-dependent deacetylase sirtuin-1(SIRT1), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), nuclear respiratory factor 1,2, mitochondrial transcription factor A, along with mitochondrial DNA content via SIRT1/PGC-1α signaling. These findings suggest oyster hydrolysates could be used as a valuable natural material that inhibits skeletal muscle atrophy via regulating protein turnover and mitochondrial biogenesis.

Lithospermum erythrorhizon Alleviates Atopic Dermatitis-like Skin Lesions by Restoring Immune Balance and Skin Barrier Function in 2.4-Dinitrochlorobenzene-Induced NC/Nga Mice

The incidence of atopic dermatitis (AD), a disease characterized by an abnormal immune balance and skin barrier function, has increased rapidly in developed countries. This study investigated the anti-atopic effect of Lithospermum erythrorhizon (LE) using NC/Nga mice induced by 2,4-dinitrochlorobenzene. LE reduced AD clinical symptoms, including inflammatory cell infiltration, epidermal thickness, ear thickness, and scratching behavior, in the mice. Additionally, LE reduced serum IgE and histamine levels, and restored the T helper (Th) 1/Th2 immune balance through regulation of the IgG1/IgG2a ratio. LE also reduced the levels of AD-related cytokines and chemokines, including interleukin (IL)-1β, IL-4, IL-6, tumor necrosis factor-α (TNF-α), thymic stromal lymphopoietin, thymus and activation-regulated chemokine, macrophage-derived chemokine, regulated on activation, normal T cell expressed and secreted, and monocyte chemoattractant protein-1 in the serum. Moreover, LE modulated AD-related cytokines and chemokines expressed and secreted by Th1, Th2, Th17, and Th22 cells in the dorsal skin and splenocytes. Furthermore, LE restored skin barrier function by increasing pro-filaggrin gene expression and levels of skin barrier-related proteins filaggrin, involucrin, loricrin, occludin, and zonula occludens-1. These results suggest that LE is a potential therapeutic agent that can alleviate AD by modulating Th1/Th2 immune balance and restoring skin barrier function.

Synergetic effect of soluble whey protein hydrolysate and Panax ginseng berry extract on muscle atrophy in hindlimb-immobilized C57BL/6 mice

Background

Sarcopenia, defined as loss of muscle mass and strength with age, becomes a public health concern as the elderly population increases. This study aimed to determine whether the mixture of soluble whey protein hydrolysate (WPH) and Panax ginseng berry extract (GBE) has a synergetic effect on sarcopenia and, if so, to identify the relevant mechanisms and optimal mixing ratio.

Methods

In the first experiment, C57BL/6 mice were hindlimb immobilized for one-week and then administered WPH 800 mg/kg, GBE 100 mg/kg, WPH 800 mg/kg+ GBE 100 mg/kg mixture, and Fructus Schisandrae extract (SFE) 200 mg/kg for two weeks. In the second experiment, experimental design was same, but mice were administered three different doses of WPH and GBE mixture (WPH 800 mg/kg+ GBE 100 mg/kg, WPH 800 mg/kg+ GBE 90 mg/kg, WPH 1000 mg/kg+ GBE 75 mg/kg).

Results

In the first experiment, we confirmed the synergetic effect of WPH and GBE on muscle mass and identified that GBE was more effective on the protein synthesis side, and WPH tended to be slightly more effective for protein degradation. In the second experiment, among three different ratios, the WPH 800 mg/kg+ GBE 100 mg/kg was most effective for muscle mass and strength. The mixtures activated muscle protein synthesis via PI3K/Akt/mTORc1 pathway and inhibited muscle protein degradation via suppressing ubiquitin-proteasome system (UPS) and autophagy-lysosome system (ALS), and these effects were more GBE dose-dependent than WPH.

Conclusion

The WPH and GBE mixture having a synergetic effect is a potential agent to prevent sarcopenia.

Acer tataricum subsp. ginnala Inhibits Skin Photoaging via Regulating MAPK/AP-1, NF-κB, and TGFβ/Smad Signaling in UVB-Irradiated Human Dermal Fibroblasts

Skin, the organ protecting the human body from external factors, maintains structural and tensile strength by containing many collagen fibrils, particularly type I procollagen. However, oxidative stress by ultraviolet (UV) exposure causes skin photoaging by activating collagen degradation and inhibiting collagen synthesis. Acer tataricum subsp. ginnala extract (AGE) is a herbal medicine with anti-inflammatory and anti-oxidative effects, but there is no report on the protective effect against skin photoaging. Therefore, we conducted research concentrating on the anti-photoaging effect of Acer tataricum subsp. ginnala (AG) in UVB (20 mJ/cm²)-irradiated human dermal fibroblasts (HDF). Then, various concentrations (7.5, 15, 30 µg/mL) of AGE were treated in HDF for 24 h following UVB irradiation. After we performed AGE treatment, the matrix metalloproteinase1 (MMP1) expression was downregulated, and the type I procollagen level was recovered. Then, we investigated the mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1) and nuclear factor-κB (NF-κB) pathway, which induce collagen breakdown by promoting the MMP1 level and pro-inflammatory cytokines. The results indicated that AGE downregulates the expression of the MAPK/AP-1 pathway, leading to MMP1 reduction. AGE inhibits nuclear translocation of NF-κB and inhibitor of nuclear factor-κB (IκB) degradation. Therefore, it downregulates the expression of MMP1 and pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 increased by UVB. Besides, the TGFβ/Smad pathway, which is mainly responsible for the collagen synthesis in the skin, was also analyzed. AGE decreases the expression of Smad7 and increases TGFβRII expression and Smad3 phosphorylation. This means that AGE stimulates the TGFβ/Smad pathway that plays a critical role in promoting collagen synthesis. Thus, this study suggests that AGE can be a functional material with anti-photoaging properties.

Anti-Osteoarthritic Mechanisms of Chrysanthemum zawadskii var. latilobum in MIA-Induced Osteoarthritic Rats and Interleukin-1β-Induced SW1353 Human Chondrocytes

Background and objectives: Chrysanthemum zawadskii var. latilobum (CZ), which has traditionally been used as a oriental tea in Asia, is known to have anti-inflammatory effects in osteoarthritis (OA). But the mechanism of these effects has not been made clear and it needs to be elucidated specifically for the clinical use of CZE in OA. Materials and Methods: To reveal this mechanism, we first identified which biomarkers were expressed in the joints of rats in which OA had been induced with monosodium iodoacetate and determined whether CZ extract (CZE) could normalize these biomarkers in the progression of OA. The anti-osteoarthritis effect of CZE was evaluated for its capability to inhibit levels of extracellular matrix (ECM)-degrading enzymes and enhance ECM synthesis. We also sought to identify whether the marker compound of CZE, linarin, has anti-osteoarthritic effects in the human chondrosarcoma cell line SW1353. Results: The changes in matrix metalloproteinases (MMPs) were remarkable: among them, MMP-1, MMP-3, MMP-9 and MMP-13 were most strongly induced, whereas their expressions were inhibited by CZE dose dependently. The expressions of the ECM synthetic genes, COL2A1 and ACAN, and the transcription factor SOX9 of these genes were reduced by OA induction and significantly normalized by CZE dose dependently. SOX9 is also a repressor of ECM-degrading aggrecanases, ADAMTS-4 and ADAMTS-5, and CZE significantly reduced the levels of these enzymes dose dependently. Similar results were obtained using the human chondrosarcoma cell line SW1353 with linarin, the biologically active compound of CZE. Conclusions: These anti-osteoarthritic effects suggest that CZE has mechanisms for activating ECM synthesis with SOX9 as well as inhibiting articular ECM-degrading enzymes.

Inhibitory effect of oyster hydrolysate on wrinkle formation against UVB irradiation in human dermal fibroblast via MAPK/AP-1 and TGFβ/Smad pathway

The skin keeps the human body healthy from extrinsic stimuli such as ultraviolet (UV) irradiation. However, chronic exposure of these stimuli reduces the number of proteins that constitute the extracellular matrix (ECM) and causes wrinkle formation. The amount of collagen, the main protein that constitutes connective tissue, is reduced in the human skin due to UV radiation. When human dermal fibroblasts were damaged by UVB, UVB increased the MMPs expressions and degraded type I collagen and other ECM proteins. Oyster (Crassostrea gigas) hydrolysate (OH) is known to have anticancer, antioxidant, and anti-apoptotic effects. To scrutinize the anti-wrinkle effect of the OH in the viewpoint of the balance between collagen degradation and synthesis, we conducted the study in UVB damaged human dermal fibroblasts. We determined type I procollagen, MMPs and related proteins using ELISA kit, qRT-PCR and western blot. In our study, we discovered that OH inhibits collagen degradation by regulating MAPKs, AP-1 and MMPs expression. Also, we found that OH promotes collagen production by enhancing TGFβ receptor II expression and Smad3 phosphorylation. These results showed that OH regulates collagen degradation and stimulates collagen synthesis. Through this study, we found that OH is effective in inhibiting wrinkle formation and restore photo-aged human skin. It indicates that OH can be one of the functional materials in the fields of anti-wrinkle research.

Protective effect of Prunella vulgaris var. L extract against blue light induced damages in ARPE-19 cells and mouse retina

Age-related macular degeneration (AMD) is one of leading causes that induce severe visual impairment and loss in the elderly. Previous studies have suggested that blue light (BL) could induce retinal degeneration, which is a major cause of the onset and development of severe AMD. In the retinal pigment epithelium (RPE) cells, A2E, a lipofuscin fluorophore, is accumulated with aging. When A2E is exposed to BL, it is easily oxidized to A2E-epoxides, leading to oxidative stress and inflammatory response in retina. The aim of this study was to investigate protective effect of Prunella vulagris (P.V) extract against oxidative stress and inflammation caused by BL, and to elucidate the underlying mechanisms in the cultured RPE cells and balb-c mice. In both model studies, P.V extract activated NF-E2 related factor 2 (Nrf-2)/hemeoxygenase-1 (HO-1) signaling pathway, followed by inhibition of ROS/MDA production, GSH depletion and reduction in SOD activity. Furthermore, P.V extract inhibited upregulation of inflammatory related genes (interlukin (IL)-1beta, IL-6, monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor A (VEGF A)) and BL induced RPE cell death, determined by cell viability and histological analyses. The mechanism of protection against inflammation by P.V extract involves inhibition of nuclear translocation of nuclear factor kappa beta (NF-kB) along with degradation of NF-kB inhibitor alpha (IkB alpha). The results suggest that P.V extract could be a potential intervention to prevent the onset and development of severe AMD.

Sesamum indicum L. Oil and Sesamin Induce Auditory-Protective Effects Through Changes in Hearing Loss-Related Gene Expression

Changing consumption patterns and increasing health awareness, especially in Europe, are resulting in an increased demand for sesame seeds. In 2016, Asia imported the highest quantity of sesame seeds, followed by Europe and North America. We examined, for the first time, the effects of treatment with sesame oil and sesamin in hearing impairment models. Sesame oil exhibited an ameliorative effect on auditory impairment in a hair cell line in zebrafish and mice. In ototoxic zebrafish larvae, neuromasts and otic cells increased in numbers because of sesame oil. Furthermore, auditory function in noise-induced hearing loss (NIHL) was studied through auditory brainstem response to evaluate the therapeutic effects of sesame oil. Sesame oil reduced the hearing threshold shift in response to clicks and 8, 16-kHz tone bursts in NIHL mice. Auditory-protective effect of sesame oil was seen in zebrafish and mice; therefore, we used chromatographic analysis to study sesamin, which is the major effective factor in sesame oil. To investigate its effects related to auditory function, we studied the hearing-related gene, Tecta, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT) assay. Auditory cell proliferation was induced by treatment with sesame oil and sesamin using Tecta (Tectorin Alpha) regulation. The expression of Tecta increases in the apex area of the cochlear hair cells as they grow, and their activity is enhanced by sesame oil and sesamin. These results provide a novel mechanistic insight into the sesame oil activities and suggest that sesamin, the key constituent in sesame oil, is responsible for its auditory function related benefits, including protection of auditory cells and reversal of their impairments.

Low molecular polypeptide from oyster hydrolysate recovers photoaging in SKH-1 hairless mice

When the human skin is chronically exposed to external stimuli such as ultraviolet (UV) radiation, the skin tissue suffers damage and the structure of the extracellular matrix (ECM) in the skin is disrupted. This eventually causes symptoms such as wrinkles loss of elasticity, skin sagging, and skin cancer. We previously found that hydrolysate extracted from pacific oyster (Crassostrea gigas) is effective in improving wrinkle formation. In this study, we selected a pentapeptide that was expected to have the most wrinkle reduction effect among the various peptides in oyster hydrolysate through preliminary in vitro screening and examined whether the pentapeptide derived from oyster hydrolysate (OHP) is effective in reducing wrinkles in vivo. We investigated the wrinkle-reducing effect of the OHP through 18-week SKH-1 hairless mice model. Our results showed that the OHP reduces wrinkles lengths, depths, and epidermal thickness which were increased by UVB radiation, and restores the amount of collagen. The OHP recovered the activity of antioxidant enzymes and regulated the expression of proinflammatory cytokines. We also found that OHP increases the expression of type I collagen through stimulating the TGFβ/Smad signaling pathway and inhibits the MMPs expression by regulating the MAPK/AP-1 signaling pathway. This study has shown that the OHP plays crucial roles in collagen production and wrinkle reduction in hairless mice and we proved the possibility of the OHP as a component for inhibiting wrinkle formation which was induced by photoaging.

Oral administration of oyster (Crassostrea gigas) hydrolysates protects against wrinkle formation by regulating the MAPK pathway in UVB-irradiated hairless mice

Chronic ultraviolet (UV) irradiation induces wrinkle formation. UV exposure increases reactive oxygen species (ROS) and upregulates the expression of matrix metalloproteinases (MMPs), which results in skin photoaging. Oyster (Crassostrea gigas), which is an abundant food resource in Asia and Europe, contains various sources of biological compounds and has several effects. Also, oyster hydrolysate (OH) has many biological activities. We investigated the inhibitory effects of OH on wrinkle formation in UVB-irradiated hairless mice. We induced UVB irradiation in hairless mice for 18 weeks and administered OH orally from the 9th week to the 18th week. We performed skin replicas and histological analyses in UVB-irradiated hairless mice dorsal skins. To determine the inhibitory mechanism of OH on wrinkle formation, we measured gene and protein expressions in dorsal skin using RT-qPCR and western blot analyses respectively. In our study, OH decreases wrinkle formation, epidermal thickness and collagen degradation in UVB-irradiated hairless mice. The gene expressions of MMPs were decreased and the gene expressions of collagen type I and TIMP-1 were increased in OH administered groups. Like gene expression tendencies, the protein expressions of MMPs were reduced and that of collagen type I was increased. Furthermore, the phosphorylation levels of ERK, JNK, and p38 were reduced in OH administered groups. We found that OH inhibits wrinkle formation, skin thickening, and collagen degradation by downregulating the MMP expression via the regulation of phosphorylation of MAPK. The results showed that OH significantly prevents UVB-induced photoaging in dorsal skin. Consistent with in vivo data, OH has potential as an anti-wrinkle agent.

Panax ginseng (Korea Red Ginseng) repairs diabetic sensorineural damage through promotion of the nerve growth factor pathway in diabetic zebrafish

Background

Diabetic sensorineural damage is a complication of the sensory neural system, resulting from long-term hyperglycemia. Red ginseng (RG) has shown efficacy for treatment of various diseases, including diabetes mellitus; however, there is little research about its benefit for treating sensorineural damage. Therefore, we aim to evaluate RG efficacy in alloxan-induced diabetic neuromast (AIDN) zebrafish.

Methods

In this study, we developed and validated an AIDN zebrafish model. To assess RG effectiveness, we observed morphological changes in live neuromast zebrafish. Also, zebrafish has been observed to have an ultrastructure of hair-cell cilia under scanning electron microscopy. Thus, we recorded these physiological traits to assess hair cell function. Finally, we confirmed that RG promoted neuromast recovery via nerve growth factor signaling pathway markers.

Results

First, we established an AIDN zebrafish model. Using this model, we showed via live neuromast imaging that RG fostered recovery of sensorineural damage. Damaged hair cell cilia were recovered in AIDN zebrafish. Furthermore, RG rescued damaged hair cell function through cell membrane ion balance.

Conclusion

Our data suggest that RG potentially facilitates recovery in AIDN zebrafish, and its mechanism seems to be promotion of the nerve growth factor pathway through increased expression of topomyosin receptor kinase A, transient receptor potential channel vanilloid subfamily type 1, and mitogen-activated protein kinase phosphorylation.

Polyphenol-enriched fraction of Vaccinium uliginosum L. protects selenite-induced cataract formation in the lens of Sprague-Dawley rat pups

PURPOSE

As the aging population is increasing, the incidence of age-related cataract is expected to increase globally. The surgical intervention, a treatment for cataract, still has complications and is limited to developed countries. In this study, we investigated whether the polyphenol-enriched fraction of Vaccinium uliginosum L. (FH) prevents cataract formation in Sprague-Dawley (SD) rat pups.

METHODS

Sixty rat pups were randomly divided into six groups: CTL, Se, FH40, FH80, FH120, and Cur80. The cataract was induced with subcutaneous injection of sodium selenite (18 μmol/kg bodyweight) on postnatal (P) day 10. All groups, except CTL, were injected with sodium selenite, and the FH40, FH80, and FH120 groups were given gastric intubation with FH40 mg/kg, 80 mg/kg, and 120 mg/kg on P9, P10, and P11. The Cur80 group was also given gastric intubation with curcumin 80 mg/kg on P9, P10, and P11. All rat pups were euthanized on P30.

RESULTS

Lens morphological analysis showed that FH dose-dependently inhibited cataract formation. In the Se group, soluble proteins were insolubilized, and the gene expression of the α-, β-, and γ-crystallins was downregulated. However, FH treatment statistically significantly inhibited insolubilization of soluble proteins and downregulation of the gene expression of the α-, β-, and γ-crystallins. In the Se group, the gene and protein levels of m-calpain were downregulated, which were attenuated with FH treatment. In addition, sodium selenite injection caused reduced antioxidant enzymes (superoxide dismutase (SOD) and glutathione peroxidase (GPx)), glutathione (GSH) depletion, and malondialdehyde (MDA) production in the lens. The administration of FH inhibited sodium selenite-induced oxidative stress in a dose-dependent manner. The mechanism of protection against oxidative stress by FH involves NF-E2-related factor (Nrf-2) and hemoxygenase-1 (HO-1). FH treatment inhibited decrease of Nrf-2 in the nucleus fraction and HO-1 in the cytosol fraction. Finally, the FH treatment protected poly (ADP)-ribose polymerase (PARP) from cleavage, determined with western blotting.

CONCLUSIONS

FH showed a preventive effect against cataract formation by inhibiting m-calpain-mediated proteolysis and oxidative stress in the lens. These results suggest that FH could be a potential anticataract agent in age-related cataract.

Anti-melanogenic effects of oyster hydrolysate in UVB-irradiated C57BL/6J mice and B16F10 melanoma cells via downregulation of cAMP signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Pacific oyster (Crassostrea gigas) has been used to treat pigmentary disorders such as freckles, melasma, and moles in Korea.

AIM OF THE STUDY

We aimed to investigate the inhibitory effects of oyster hydrolysate (OH) on melanogenesis in B16F10 melanoma cells and UVB-irradiated C57BL/6J mice.

MATERIAL AND METHODS

The molecular weight distribution and peptide sequences of OH were detected using MALDI-TOF and UHPLC. To evaluate the anti-melanogenic effects of OH, cell viability, melanin content, tyrosinase activity, intracellular cyclic adenosine monophosphate (cAMP) and protein expressions levels were measured in B16F10 cells. In addition, OH was orally administered to UVB-irradiated mice for 9 weeks. After sacrificing the mice, the whitening effects of OH were evaluated based on histological observations and protein expression levels.

RESULTS

In B16F10 cells, OH decreased melanin content and tyrosinase activity in a dose-dependent manner. OH exhibited anti-melanogenic activities via downregulation of cAMP signaling pathway, which consequently decreased melanin synthesis. In UVB-irradiated mice groups, OH decreased the number of active melanocytes and melanin granules. The expression of tyrosinase-related proteins and microphthalmia-associated transcription factor (MITF) decreased in the OH-administered groups.

CONCLUSIONS

These results show that OH inhibits melanin synthesis in B16F10 cells via downregulation of cAMP signaling pathway and in UVB-irradiated mice, by decreasing the number of active melanocytes and melanin granules.

Avocado Oil Extract Modulates Auditory Hair Cell Function through the Regulation of Amino Acid Biosynthesis Genes

Sensorineural hearing loss (SNHL) is one of the most common causes of disability, affecting over 466 million people worldwide. However, prevention or therapy of SNHL has not been widely studied. Avocado oil has shown many health benefits but it has not yet been studied in regards to SNHL. Therefore, we aimed to investigate the efficacy of avocado oil on SNHL in vitro and in vivo and elucidate its mode of action. For the present study, we used enhanced functional avocado oil extract (DKB122). DKB122 led to recovery of otic hair cells in zebrafish after neomycin-induced otic cell damage. Also, DKB122 improved auditory sensory transmission function in a mouse model of noise induced-hearing loss and protected sensory hair cells in the cochlea. In addition, RNA sequencing was performed to elucidate the mechanism involved. KEGG pathway enrichment analysis of differentially expressed genes showed that DKB122 protected House Ear Institute-Organ of Corti 1 (HEI-OC1) cells against neomycin-related alterations in gene expression due to oxidative stress, cytokine production and protein synthesis.

Quercetin-3-O-α-l-arabinopyranoside protects against retinal cell death via blue light-induced damage in human RPE cells and Balb-c mice

Age-related macular degeneration (AMD) is among the increasing number of diseases causing irreversible blindness in the elderly. Dry AMD is characterized by the accumulation of lipofuscin in retinal pigment epithelium (RPE) cells. N-Retinylidene-N-retinylethanolamine (A2E), a component of lipofuscin, is oxidized to oxo-A2E under blue light illumination, leading to retinal cell death. The aim of this study was to investigate the protective effect and mechanism of quercetin-3-O-α-l-arabinopyranoside (QA) against blue light (BL)-induced damage in both RPE cells and mice models. Treatment by QA inhibited A2E uptake in RPE cells, as determined by a decrease in fluorescence intensity. QA also protected A2E-laden RPE cells against BL-induced apoptosis. QA inhibited C3 complement activation and poly (ADP-ribose) polymerase (PARP) cleavage, as determined by western blotting. QA showed an inhibitory effect on AP1 and NF-kB activity as estimated in a reporter gene assay. In addition, QA activated the gene expression of aryl hydrocarbon receptor target genes (CYP1A1, CYP1B1) in TCDD-treated RPE cells. In the mice model, oral administration of QA protected against retinal degeneration induced by BL exposure as determined by histological analyses (thickness of retinal layers and immunostaining for caspase-3). In addition, QA inhibited apoptosis and inflammation via inhibition of NF-kB p65 translocation, C3 activation, and PARP cleavage. Collectively, these results revealed the protective mechanism of QA against BL-induced retinal damage both in vitro and in vivo.

Hepaprotective Effect of Standardized Ecklonia stolonifera Formulation on CCl4-Induced Liver Injury in Sprague-Dawley Rats

The liver is an essential organ for the detoxification of exogenous xenobiotics, drugs and toxic substances. The incidence rate of non-alcoholic liver injury increases due to dietary habit change and drug use increase. Our previous study demonstrated that Ecklonia stolonifera (ES) formulation has hepatoprotective effect against alcohol-induced liver injury in rat and tacrine-induced hepatotoxicity in HepG2 cells. This present study was designated to elucidate hepatoprotective effects of ES formulation against carbon tetrachloride (CCl₄)-induced liver injury in Sprague Dawley rat. Sixty rats were randomly divided into six groups. The rats were treated orally with ES formulation and silymarin (served as positive control, only 100 mg/kg/day) at a dose of 50, 100, or 200 mg/kg/day for 21 days. Seven days after treatment, liver injury was induced by intraperitoneal injection of CCl₄ (1.5 ml/kg, twice a week for 14 days). The administration of CCl₄ exhibited significant elevation of hepatic enzymes (like AST and ALT), and decrease of antioxidant related enzymes (superoxide dismutase, glutathione peroxidase and catalase) and glutathione. Then, it leaded to DNA damages (8-oxo-2′-deoxyguanosine) and lipid peroxidation (malondialdehyde). Administration of ES formulation inhibited imbalance of above factors compared to CCl₄ induced rat in a dose dependent manner. Real time PCR analysis indicates that CYP2E1 was upregulated in CCl₄ induced rat. However, increased gene expression was compromised by ES formulation treatment. These findings suggests that ES formulation could protect hepatotoxicity caused by CCl₄ via two pathways: elevation of antioxidant enzymes and normalization of CYP2E1 enzyme.

Anti-obesity effects of Spirulina maxima in high fat diet induced obese rats via the activation of AMPK pathway and SIRT1

Spirulina maxima improved the obese phenotype in high fat diet induced rats by activating AMPK and SIRT1.

Pinus densiflora bark extract prevents selenite-induced cataract formation in the lens of Sprague Dawley rat pups

PURPOSE

Rat pups treated with sodium selenite are typically used as an in vivo model to mimic age-related nuclear cataract. Reactive oxygen species (ROS) production, lipid peroxidation, reduction of antioxidant enzymes, crystalline proteolysis, and apoptosis are considered factors that contribute to pathogenesis of age-related nuclear cataract. In the present study, we investigated whether Pinus densiflora bark extract has potential to prevent cataract formation and elucidated the underlying mechanism.

METHODS

Sprague Dawley rats were divided into six groups (n=10). Group 1 rat pups (the control) were treated with only normal saline. The rat pups in groups 2 to 6 were given a subcutaneous injection with sodium selenite (18 μmol/kg bodyweight) on postnatal (P) day 10. Group 3 rat pups (the positive control) were given gastric intubation with curcumin (80 mg/kg bodyweight) on P9, P10, and P11. The rat pups in groups 4 to 6 were given gastric intubation with P. densiflora bark extract 40 mg/kg, 80 mg/kg, and 120 mg/kg, respectively, on P9, P10, and P11.

RESULTS

This study showed that P. densiflora bark extract dose-dependently prevented cataract formation. Water-soluble protein, glutathione, superoxide dismutase, glutathione peroxidase, and catalase activity levels were found to be high, and conversely, water-insoluble protein, malondialdehyde, and Ca²⁺-ATPase were found to be low in the groups treated with P. densiflora bark extract compared to group 2. Real-time PCR analysis showed αA-crystalline, lens-specific m-calpain (Lp84), lens-specific intermediates (filensin and phakinin), and antiapoptotic factor (Bcl-2) were downregulated, and the apoptotic factors (caspase-3 and Bax) and plasma membrane Ca²⁺-ATPase (PMCA-1) were upregulated in group 2 compared to group 1. P. densiflora bark extract regulated the imbalance of these genes. The increased cleavage form of caspase-3 was lowered in the groups treated with P. densiflora bark extract. In conclusion, P. densiflora bark extract prevented selenite-induced cataract formation via regulating antioxidant enzymes, inhibiting m-calpain-induced proteolysis, and apoptosis, and thus, maintained the transparency of the lens.

CONCLUSIONS

These results suggested that P. densiflora bark extract could be a new agent for preventing age-related nuclear cataract.

Germacrone Attenuates Hyperlipidemia and Improves Lipid Metabolism in High-Fat Diet-Induced Obese C57BL/6J Mice

We previously showed that Aster spathulifolius Maxim extract (ASE) reduced body weight gain and serum and liver lipid levels and significantly suppressed serum insulin and leptin concentrations in high-fat diet (HFD)-induced obese rats. Germacrone (GM) was identified as a potent bioactive constituent of ASE. In this study, we hypothesized that GM can attenuate hyperlipidemia by alleviating fatty acid (FA) synthesis/uptake and improve lipid metabolism by stimulating FA β-oxidation in HFD-induced obese C57BL/6J mice. To induce obesity, mice were fed an HFD for 6 weeks, while control mice were fed a commercial standard diet. The mice were allocated to six groups and fed either a normal diet, HFD, HFD with GM (5, 10, and 20 mg/kg), or HFD with 200 mg/kg Garcinia cambogia extract for 30 days. In the GM groups, body weight gain, visceral fat pad weight, fasting plasma glucose, serum insulin and leptin, and serum, as well as hepatic lipid, levels were attenuated. Transcriptional factors related to lipid metabolism, such as AMP-activated protein kinase α, sterol regulatory element-binding protein (SREBP) 1, SREBP 2, acetyl-CoA carboxylase, peroxisome proliferator-activated receptor (PPAR)-α, PPAR-γ, FA synthase, and carnitine palmitoyltransferase 1, showed higher expression in the GM groups. In summary, GM may help attenuate hyperlipidemia by suppressing FA synthesis and uptake by inhibiting SREBP signaling pathway activation and improve lipid metabolism by stimulating FA β-oxidation by activating the AMPKα signaling pathway in HFD-induced obesity.

Germacrone inhibits adipogenesis and stimulates lipolysis via the AMP-activated protein kinase signalling pathway in 3T3-L1 preadipocytes

OBJECTIVES

In a previous study, we reported that Aster spathulifolius Maxim extract (ASE) inhibited lipid accumulation and adipocyte differentiation in 3T3-L1 cells. Of the components in ASE, germacrone (GM) was identified as a potent bioactive constituent. GM is known for its anticancer and antiviral activity. However, the effects of GM and the molecular mechanism by which GM regulates adipogenesis and lipolysis were not reported. Therefore, we investigated the effect of GM on adipogenesis and lipolysis and to elucidate its underlying molecular mechanism.

METHODS

We analysed the contents of intracellular triglyceride and carried out Western blotting and RT-qPCR to investigate the underlying mechanism.

KEY FINDINGS

We demonstrate that GM suppresses adipogenic differentiation and the increase in lipolysis in 3T3-L1 cells. In particular, GM down-regulates the expression of early adipogenesis-related genes (e.g. KLF4, KLF5, C/EBP-β and C/EBP-δ) and major adipogenesis-related genes (C/EBP-α and PPAR-γ). Furthermore, GM increases the protein levels of phosphorylated AMP-activated protein kinase α (AMPKα), phosphorylated acetyl-coenzyme A carboxylase (ACC) and carnitine palmitoyltransferase (CPT1).

CONCLUSIONS

Our results suggest that GM may be a potent bioactive anti-adipogenic and lipolytic constituent via the regulation of adipogenesis, lipolysis and the AMPKα pathway.

Polyphenol-enriched Vaccinium uliginosum L. fractions reduce retinal damage induced by blue light in A2E-laden ARPE19 cell cultures and mice

Polyphenols exert beneficial effects on vision. We hypothesized that polyphenol components of Vaccinium uliginosum L. (V.U.) extract protect retinal pigment epithelial (RPE) cells against blue light-induced damage. Our aim was to test extracts containing polyphenol components to ascertain effects to reduce damage against blue light in RPEs. We measured the activity in fractions eluted from water, ethanol, and HP20 resin (FH), and found that the FH fraction had the highest beneficial activity. We isolated the individual active compounds from the FH fraction using chromatographic techniques, and found that FH contained flavonoids, anthocyanins, phenyl propanoids, and iridoids. Cell cultures of A2E-laden ARPE-19 exposed to blue light after treatment with V.U. extract fractions and their individual constituents indicated improvement. V uliginosum L extract fractions and constituent compounds significantly reduced A2E photo-oxidation-induced RPE cell death and inhibited intracellular A2E accumulation. Furthermore, Balb/c male mice were exposed to blue light at 10000 lux for 1 h/d for 2 weeks to induce retinal damage. One week after the final blue light exposure, retinal damage evaluated revealed that the outer nuclear layer thickness and nuclei count were improved. Histologic examination of murine photoreceptor cells demonstrated that FH, rich in polyphenols, inhibited the loss of outer nuclear layer thickness and nuclei. Our findings suggest that V.U. extract and eluted fractions are a potential source of bioactive compounds that potentially serve a therapeutic approach for age-related macular degeneration.

Protective Effects of Ecklonia stolonifera Extract on Ethanol-Induced Fatty Liver in Rats

Chronic alcohol consumption causes alcoholic liver disease, which is associated with the initiation of dysregulated lipid metabolism. Recent evidences suggest that dysregulated cholesterol metabolism plays an important role in the pathogenesis of alcoholic fatty liver disease. Ecklonia stolonifera (ES), a perennial brown marine alga that belongs to the family Laminariaceae, is rich in phlorotannins. Many studies have indicated that ES has extensive pharmacological effects, such as antioxidative, hepatoprotective, and antiinflammatory effects. However, only a few studies have investigated the protective effect of ES in alcoholic fatty liver. Male Sprague-Dawley rats were randomly divided into normal diet (ND) (fed a normal diet for 10 weeks) and ethanol diet (ED) groups. Rats in the ED group were fed a Lieber-DeCarli liquid diet (containing 5% ethanol) for 10 weeks and administered ES extract (50, 100, or 200 mg/kg/day), silymarin (100 mg/kg/day), or no treatment for 4 weeks. Each treatment group comprised of eight rats. The supplementation with ES resulted in decreased serum levels of triglycerides (TGs), total cholesterol, alanine aminotransferase, and aspartate aminotransferase. In addition, there were decreases in hepatic lipid and malondialdehyde levels. Changes in liver histology, as analyzed by Oil Red O staining, showed that the ES treatment suppressed adipogenesis. In addition, the ES treatment increased the expression of fatty acid oxidation-related genes (e.g., PPAR-α and CPT-1) but decreased the expression of SREBP 1, which is a TG synthesis-related gene. These results suggest that ES extract may be useful in preventing fatty acid oxidation and reducing lipogenesis in ethanol-induced fatty liver.

Protective effects of resveratrol and its analogs on age-related macular degeneration in vitro

Damage of retinal pigment epithelial (RPE) cells by A2E may be critical for age-related macular degeneration (AMD) management. Accumulation and photooxidation of A2E are known to be one of the critical causes in AMD. Here, we evaluated the protective effect of resveratrol (RES), piceatannol (PIC) and RES glycones on blue-light-induced RPE cell death caused by A2E photooxidation. A2E treatment followed by blue light exposure caused significant damages on human RPE cells (ARPE-19). But the damages were attenuated by post- and pre-treatment of RES and PIC in our in vitro models. The results of cell free system and FAB-MS analysis clearly showed that the reduction of A2E by blue light exposure was significantly rescued, and that oxidized forms of A2E were significantly reduced by RES or PIC treatment. Besides, RES or PIC inhibited the intracellular accumulation of A2E. Not only RES and PIC but RES glycones showed protection of ARPE-19 cells against A2E and blue-light-induced photo-damage. These findings demonstrate that RES and its analogs may have protective effects against A2E and blue-light-induced ARPE-19 cell death through regulation of A2E accumulation as well as photooxidation of A2E. Thus RES and its analogs may be beneficial for AMD treatment.

A novel fluorescence-based assay for measuring A2E removal from human retinal pigment epithelial cells to screen for age-related macular degeneration inhibitors

Age-related macular degeneration (AMD) is a common retinal disease that leads to irreversible central vision loss in the elderly population. Recent studies have identified many factors related to the development of dry AMD, such as aging, cigarette smoking, genetic predispositions, and oxidative stress, eventually inducing the accumulation of lipofuscin, which is one of the most critical risk factors. One of the major lipofuscins in retinal pigment epithelial (RPE) cells is N-retinylidene-N-retinylethanolamine (also known as A2E), a pyridinium bis-retinoid. Currently there is a lack of effective therapy to prevent or restore vision loss caused by dry AMD. Recent studies have shown that 430 nm blue light induces the oxidation of A2E and the activation of caspase-3 to subsequently cause the death of RPE cells, suggesting that removal of A2E from retinal pigment cells might be critical for preventing AMD. Here, we developed a fluorescence-labeled A2E analog (A2E-BDP) that functions similar to A2E in RPE cells, but is more sensitive to detection than A2E. A2E-BDP-based tracing of intracellular A2E will be helpful, not only for studying the accumulation and removal of A2E in human RPE cells but also for identifying possible inhibitors of AMD.

Germacrone Inhibits Estrogen Receptor α-Mediated Transcription in MCF-7 Breast Cancer Cells

Estrogen receptor (ER)α-positive breast cancer cells regulate the expression of estrogen-responsive genes, which are involved in cell proliferation, differentiation, and cell cycle progression. Clinically, the inhibition of ERα-mediated gene expression in breast cancer cells has long been considered an effective way to prevent the development and progression of cancer. Germacrone, a terpenoid compound isolated from Rhizoma curcuma, has been known to have antitumor activity in various human cancer cell lines. However, the mechanism by which germacrone inhibits the proliferation of breast cancer cells is still unclear. Here, we demonstrated that germacrone inhibits ERα-mediated gene expression at the transcriptional level in MCF-7 cells. Germacrone inhibits the recruitment of ERα to the estrogen response element on chromatin and consequently compromises the binding of switch/sucrose non-fermentable chromatin remodeling complex and RNA polymerase II to target gene promoter, thereby inhibiting the estrogen-induced chromatin accessibility. In addition, germacrone efficiently potentiates the antitumor activity of methotrexate and 5-fluorouracil. Our results not only provide substantial molecular mechanism of germacrone on ERα-mediated signaling in breast cancer cells but also demonstrate the benefits of germacrone as a combination therapy with other drugs for the treatment of breast cancer. Copyright © 2016 John Wiley & Sons, Ltd.

Solanum tuberosum L. cv Hongyoung extract inhibits 2,4‑dinitrochlorobenzene‑induced atopic dermatitis in NC/Nga mice

Solanum tuberosum L. cv Hongyoung (SH) is a widely consumed anthocyanin-rich food and medicinal plant, which possesses anti-inflammatory and anti-allergic activities. The present study aimed to examine the inhibitory effects of SH extract on atopic dermatitis (AD)-like skin lesions induced by the topical application of 2,4-dinitrochlorobenzene (DNCB) in NC/Nga mice. SH extract was orally administered to the DNCB-treated NC/Nga mice. The anti-AD effects of SH extract were examined by measuring symptom severity; ear thickness; scratching behavior; serum levels of immunoglobulin (Ig)E; T-helper (Th)1, Th2 and Th17 cytokine levels in the spleen; mRNA expression levels of inflammatory cytokines and chemokines; and tissue infiltration of inflammatory cells. The results demonstrated that SH extract inhibited the development of AD-like lesions, and reduced IgE levels and the production of cytokines. Furthermore, SH extract significantly suppressed the expression of AD-associated mRNAs in lesional skin. Histological alterations in the AD-like lesions were visualized using hematoxylin and eosin, and toluidine blue staining in the DNCB-treated group; the alterations were attenuated following SH treatment. In addition, thickening of the epidermis and accumulation of inflammatory cells in the DNCB-treated mice were suppressed by SH treatment. These results suggested that SH extract may suppress the development of AD symptoms through modulation of the Th1 and Th2 responses.

Anti-melanogenic effects of Aster spathulifolius extract in UVB-exposed C57BL/6J mice and B16F10 melanoma cells through the regulation of MAPK/ERK and AKT/GSK3β signalling

OBJECTIVES

Pharmacological studies of Aster spathulifolius Maxim(AS) have demonstrated its anti-allergy, anti-viral and anti-obesity effects, however, its anti-melanogenic effects is still unclear. In this study, the effects of AS extract (ASE) on the inhibition of melanin synthesis were investigated in vitro and in vivo.

METHODS

To perform this study, the contents of melanin and tyrosinase activity were analysed in B16F10 melanoma cells. Western blotting was carried out to determine the underlyling mechanism. Additionally, we investigated the effect of this extract on hyperpigmentation in C57bL/6J mice induced by 3, 6 and 9 weeks of UVB irradiation.

KEY FINDINGS

AS extract led to reduced melanin synthesis through the regulation of MITF and its downstream signals. Furthermore, ASE increased the phosphorylation of MAPK/ERK and Akt/GSK3β signalling pathway components. In vivo study, hypopigmentation effects were also observed. The melanocyte activity and the distribution of melanin granules were decreased in UVB-irradiated mice treated with ASE.

CONCLUSIONS

These results suggest that the ASE may be promising as an active anti-melanogenic component, and further investigations should be performed regarding its potential as a whitening agent in the field of cosmetics.

Anti-Obesity Effects of Aster spathulifolius Extract in High-Fat Diet-Induced Obese Rats

The aim of this study was to investigate the anti-obesity and antihyperlipidemic efficacy and molecular mechanisms of Aster spathulifolius Maxim extract (ASE) in rats with high-fat diet (HFD)-induced obesity. Rats were separately fed a normal diet or a HFD for 8 weeks, then they were treated with ASE (62.5, 125, or 250 mg/kg) for another 4.5 weeks. The ASE supplementation significantly lowered body weight gain, visceral fat pad weights, serum lipid levels, as well as hepatic lipid levels in HFD-induced obese rats. Histological analysis showed that the ASE-treated group showed lowered numbers of lipid droplets and smaller size of adipocytes compared to the HFD group. To understand the mechanism of action of ASE, the expression of genes and proteins involved in obesity were measured in liver and skeletal muscle. The expression of fatty acid oxidation and thermogenesis-related genes (e.g., PPAR-α, ACO, CPT1, UCP2, and UCP3) of HFD-induced obese rats were increased by ASE treatment. On the other hand, ASE treatment resulted in decreased expression of fat intake-related gene ACC2 and lipogenesis-related genes (e.g., SREBP-1c, ACC1, FAS, SCD1, GPATR, AGPAT, and DGAT). Furthermore, ASE treatment increased the level of phosphorylated AMPKα in obese rats. Similarly, the level of phosphorylated ACC, a target protein of AMPKα in ASE groups, was increased by ASE treatment compared with the HFD group. These results suggest that ASE attenuated visceral fat accumulation and improved hyperlipidemia in HFD-induced obese rats by increasing lipid metabolism through the regulation of AMPK activity and the expression of genes and proteins involved in lipolysis and lipogenesis.

Effect of Coenzyme Q10 Supplementation in Statin-Treated Obese Rats

Statins, HMG-CoA reductase inhibitors, are known to cause serious muscle injuries (e.g. myopathy, myositis and rhabdomyolysis), and these adverse effects can be rescued by co-administration of coenzyme Q₁₀ (CoQ₁₀) with statins. The goal of the current research is to assess the efficacy of combined treatment of CoQ₁₀ with Atorvastatin for hyperlipidemia induced by high-fat diet in SD rats. 4-week-old Sprague-Dawley male rats were fed normal diet or high-fat diet for 6 weeks. Then, rats were treated with either Statin or Statin with various dosages of CoQ₁₀ (30, 90 or 270 mg/kg/day, p.o.) for another 6 weeks. Compared to Statin only-treatment, CoQ₁₀ supplementation significantly reduced creatine kinase and aspartate aminotransferase levels in serum which are markers for myopathy. Moreover, CoQ₁₀ supplementation with Statin further reduced total fat, triglycerides, total cholesterol, and low-density lipoprotein-cholesterol. In contrast, the levels of high-density lipoprotein-cholesterol and CoQ₁₀ were increased in the CoQ₁₀ co-treated group. These results indicate that CoQ₁₀ treatment not only reduces the side effects of Statin, but also has an anti-obesity effect. Therefore an intake of supplementary CoQ₁₀ is helpful for solving problem of obese metabolism, so the multiple prescription of CoQ₁₀ makes us think a possibility that can be solved in being contiguous to the obesity problem, a sort of disease of the obese metabolism.

Inhibitory effects of Aster spathulifolius extract on adipogenesis and lipid accumulation in 3T3-L1 preadipocytes

OBJECTIVES

Aster spathulifolius Maxim (AS), known for its anti-viral and anti-allergic activity, is also known to reduce body weight gain in high fat diet-induced obese rats. But its molecular mechanism of the anti-obesity effects is still unclear. So, we investigated the inhibitory effect of AS extract (ASE) on adipogenesis and lipid accumulation to determine the underlying cellular molecular mechanism.

METHODS

To perform this study, the contents of intracellular triglyceride were analysed. Real-time polymerase chain reaction and Western blotting were carried out to investigate the expression of adipogenic transcriptional factors.

KEY FINDINGS

ASE showed the suppression of adipogenic differentiation and the considerable reduction of the lipid accumulation in 3T3-L1 cells. Especially, ASE inhibited the early stage of differentiation via the downregulation of C/EBP-β and C/EBP-δ, which are early adipogenic factors. Major adipogenic factors, such as PPAR-γ and C/EBP-α, were also subsequently inhibited. These findings were supported by Oil Red O staining and intracellular triglyceride levels. A molecular mechanism liking the effect of ASE was identified through the activation of AMPKα pathway. ASE increased protein levels of phosphorylated AMPKα and phosphorylated ACC.

CONCLUSIONS

ASE showed anti-adipogenic and anti-lipogenic effects through the regulation of adipogenic factors and AMPKα pathway.

Protective effect of fucosterol isolated from the edible brown algae, Ecklonia stolonifera and Eisenia bicyclis, on tert-butyl hydroperoxide- and tacrine-induced HepG2 cell injury

OBJECTIVES

Fucosterol is the primary sterol found in brown algae. Recently, considerable interest has been generated regarding fucosterol due to its potential antioxidant, anti-inflammatory and antidiabetic effects. The aim of this study was to investigate the protective effects of fucosterol on tert-butyl hydroperoxide (t-BHP)- and tacrine-induced oxidative stress in HepG2 cells.

METHODS

Fucosterol by itself exhibited no cytotoxicity at concentrations below 100 μm by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The increased intracellular reactive oxygen species (ROS) and decreased glutathione levels observed in t-BHP- and tacrine-treated HepG2 cells were ameliorated by fucosterol pretreatment, indicating that the protective effects of fucosterol are mediated by the induction of cellular defence mechanisms against oxidative stress. Moreover, elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in tacrine-treated mice were significantly reduced after oral administration of fucosterol.

KEY FINDINGS

The hepatoprotective effects of fucosterol may occur via an increase in the hepatic level of glutathione and a decrease in ROS production, thereby preventing hepatic damage and the resultant increases in ALT and AST activity.

CONCLUSION

These results suggest that fucosterol may be an effective hepatoprotective agent that could be useful for preventive therapies against oxidative stress-related hepatotoxicity.

Protective effect of fucosterol isolated from the edible brown algae, Ecklonia stolonifera and Eisenia bicyclis, on tert-butyl hydroperoxide- and tacrine-induced HepG2 cell injury

OBJECTIVES

Fucosterol is the primary sterol found in brown algae. Recently, considerable interest has been generated regarding fucosterol due to its potential antioxidant, anti-inflammatory and antidiabetic effects. The aim of this study was to investigate the protective effects of fucosterol on tert-butyl hydroperoxide (t-BHP)- and tacrine-induced oxidative stress in HepG2 cells.

METHODS

Fucosterol by itself exhibited no cytotoxicity at concentrations below 100 μm by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The increased intracellular reactive oxygen species (ROS) and decreased glutathione levels observed in t-BHP- and tacrine-treated HepG2 cells were ameliorated by fucosterol pretreatment, indicating that the protective effects of fucosterol are mediated by the induction of cellular defence mechanisms against oxidative stress. Moreover, elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in tacrine-treated mice were significantly reduced after oral administration of fucosterol.

KEY FINDINGS

The hepatoprotective effects of fucosterol may occur via an increase in the hepatic level of glutathione and a decrease in ROS production, thereby preventing hepatic damage and the resultant increases in ALT and AST activity.

CONCLUSION

These results suggest that fucosterol may be an effective hepatoprotective agent that could be useful for preventive therapies against oxidative stress-related hepatotoxicity.

Oral administration of Vaccinium uliginosum L. extract alleviates DNCB-induced atopic dermatitis in NC/Nga mice

Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease that responds to the interplay of environmental, immunological, and genetic factors. To explore the effect of Vaccinium uliginosum (VU) extract on AD, we orally administrated VU total water extract to AD-induced NC/Nga mice. VU extract reduced AD-like skin lesions, ear thickness, and the frequency of scratching episodes in a time-dependent manner. VU also suppressed the levels of IgE and histamine and the ratio of IgG1/IgG2a in the serum of AD-induced NC/Nga mice. VU administration resulted in the reduction of splenic cytokine production, epidermal thickening, and the infiltration of eosinophils, mast cells, and degranulated mast cells induced by 2,4-dinitrochlorobenzene (DNCB). In addition, VU significantly reduced the mRNA expression of chemokine ligands in dorsal skin. Total water extract and subfractions of VU inhibited interleukin (IL)-4 production in splenocytes, suggesting that VU total extract has a Th2 cytokine modulating effect. These results suggest that the VU total water extract could be a candidate therapeutic agent for the treatment of AD through an immunoregulatory effect.

Inhibitory effects of Solanum tuberosum L. var. vitelotte extract on 2,4-dinitrochlorobenzene-induced atopic dermatitis in mice

OBJECTIVES

We aimed to investigate the inhibitory efficacy of Solanum tuberosum L. var. Vitelotte (SV) extract on atopic dermatitis (AD)-like skin lesions induced by the topical application of 2,4-dinitrochlorobenzene in NC/Nga mice.

METHODS

SV extract was administered orally to NC/Nga mice at the dose of 75, 150 or 300 mg/kg for 4 weeks. The effectiveness of SV extract in NC/Nga mice was evaluated by measuring symptom severity, ear thickness, scratching behaviour, serum levels of IgE, IgG1 and IgG2a, T helper 1 (Th1; interferon-γ and IL-12) and Th2 cytokines (IL-4 and IL-13) in spleen, messenger RNA (mRNA) expression of inflammatory cytokines and chemokines in tissue and infiltration of inflammatory cells in tissue.

KEY FINDINGS

Oral administration of SV extract to NC/Nga mice resulted in the inhibition of the development of AD-like skin lesions. SV extract was attenuated AD-like skin lesion, ear thickening and scratching behaviour. SV extract also alleviated infiltrated inflammatory cells in tissue. Production of Th1 and Th2 cytokines was inhibited in splenocyte cultures. Additionally, reduced levels of IgE and IgG1/IgG2a ratio in serum and expression of AD-related mRNAs in lesional skins were observed in SV-treated mice compared with control group.

CONCLUSIONS

SV extract alleviated the exacerbation of AD-like skin lesions in NC/Nga mice by suppressing total serum level of IgE and correcting the Th1/Th2 balance.

Enzogenol improves diabetes-related metabolic change in C57BL/KsJ-db/db mice, a model of type 2 diabetes mellitus

Objectives

Dietary use of pine bark extract has been associated with reduced risk of inflammation and diabetes. In this study, we investigated the antidiabetic effects of enzogenol, proanthocyanidins-rich bioflavonoid extract derived from the pine bark of New Zealand Pinus radiata trees, using C57BL/KsJ-db/db mice.

Methods

After 1-week acclimation period, the db/db mice were divided into vehicle-treated, Enzogenol-treated (12.5, 25 and 50 mg/kg; EZ) and positive control (tea polyphenol 50 mg/kg; TPP) groups.

Key findings

The administration of EZ improved the glucose tolerance and lowered the glycosylated haemoglobin (HbA1C), insulin and glucagon levels in blood. Interestingly, EZ and TPP treatments resulted in reduced hepatic free fatty acid, cholesterol and triglyceride levels in db/db mice. EZ and TPP treatments significantly elevated hepatic AMPK activity, and the expression of proteins related to glucose homeostasis and lipid metabolism, such as glucokinase, peroxisome proliferator-activated receptor (PPAR)α and long-chain acyl-CoA dehydrogenase protein level with a simultaneous reduction of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase protein expression. In addition, the EZ administration groups had an increased hepatic glycogen synthase expression in db/db mice.

Conclusions

These results suggest that EZ may be beneficial in improving insulin resistance and hyperglycaemia in type 2 diabetic mice by enhancing the glucose and lipids metabolism.

Anti-obesity effects of Boussingaulti gracilis Miers var. pseudobaselloides Bailey via activation of AMP-activated protein kinase in 3T3-L1 cells

In a previous study, we demonstrated the anti-obesity and hypolipidemic effects of Boussingaulti gracilis Miers var. pseudobaselloides Bailey in high-fat diet-induced obese rats. The present study investigated the molecular mechanisms by which B. gracilis Miers var. pseudobaselloides Bailey ethanol extract (BGE) conferred antidifferentiation and anti-adipogenic effects in the 3T3-L1 preadipocyte differentiation model. BGE treatment significantly and dose-dependently suppressed lipid accumulation and down-regulated the expression of major transcription factors involved in adipogenesis, such as peroxisome proliferator-activated receptor-γ, CCAAT/enhancer binding protein α, sterol regulatory element-binding proteins, and their target genes. It is important that treatment with BGE increased phosphorylation of AMP-activated protein kinase (AMPK), which is one of the rate-limiting enzymes in the fatty acid synthesis pathway, and its direct downstream protein, acetyl-coenzyme A carboxylase. These results suggest that BGE may exert anti-adipogenic effects through regulation of AMPK activity and expression of genes involved in lipogenesis.