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Gracilaria chorda (GC) is a red algal species that is primarily consumed in Asia. Here, we investigated the effect of GC on obesity-related skeletal muscle wasting. Furthermore, elucidating its impact on the activation of sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) constituted a critical aspect in understanding the underlying mechanism of action. In this study, 6-week-old male C57BL/6 mice were fed a high-fat diet (HFD) for 8 weeks to induce obesity, then continued on the HFD for another 8 weeks while orally administered GC. GC decreased ectopic fat accumulation in skeletal muscle and increased muscle weight, size, and function in obese mice. Furthermore, GC reduced skeletal muscle atrophy and increased hypertrophy in mice. We hypothesized that the activation of SIRT1/PGC1α by GC regulates skeletal muscle atrophy and hypertrophy. We observed that GC increased the expression of SIRT1 and PGC1α in skeletal muscle of mice and in C2C12 cells, which increased mitochondrial function and biogenesis. In addition, when C2C12 cells were treated with the SIRT1-specific inhibitor EX-527, no changes were observed in the protein levels of SIRT1 and PGC1α in the GC-treated C2C12 cells. Therefore, GC attenuated obesity-related muscle wasting by improving mitochondrial function and biogenesis through the activation of SIRT1/PGC1α in the skeletal muscle of mice.
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BACKGROUND: Exercise is an effective strategy to prevent sarcopenia, but high physical inactivity in the elderly requires alternative therapeutic approaches. Exercise mimetics are therapeutic compounds that simulate the beneficial effects of exercise on skeletal muscles. However, the toxicity and adverse effects of exercise mimetics raise serious concerns. PURPOSE: We aimed to search novel plant-based alternatives to activate exercise induced-signaling. METHODS: We used open databases and luciferase assays to identify plant-derived alternatives to activate exercise-induced signaling and compared its efficacy to mild intensity continuous training (MICT) in aged C57BL/6 mice. The nineteen-month-old mice were either fed an experimental diet supplemented with the isolated alternative or subjected to MICT for up to 21 mo of age. RESULTS: Our analysis revealed that Chrysanthemum zawadskii Herbich var latillobum (Maxim.) Kitamura (CZH), a medicinal plant rich in linarin, is a novel activator of peroxisome proliferator-activated receptor δ (PPARδ) and estrogen-related receptor γ (ERRγ), key regulators of exercise-induced positive effects on muscles. CZH supplementation ameliorated the loss of muscle function and mass, and increased PPARδ and ERRγ expression in mouse muscles. CZH also improved mitochondrial functions and proteostasis in aged mice, similar to MICT. Furthermore, CZH and linarin induced the activation of Sestrin 1, a key mediator of exercise benefits, in muscle. Silencing Sestrin 1 negated the increase in myogenesis and mitochondrial respiration by CZH and linarin in primary myoblasts from old mice. CONCLUSION: Our findings suggest the potential of CZH as a novel plant-derived alternative to activate exercise-induced signaling for preventing sarcopenia in sedentary older adults. This could offer a safer therapeutic option for sarcopenia treatment.
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Chrysanthemum , Ratones Endogámicos C57BL , Sarcopenia , Transducción de Señal , Animales , Chrysanthemum/química , Transducción de Señal/efectos de los fármacos , Ratones , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Condicionamiento Físico Animal , Masculino , PPAR delta/metabolismo , Extractos Vegetales/farmacología , Receptores de Estrógenos/metabolismo , Humanos , Envejecimiento/efectos de los fármacos , GlicósidosRESUMEN
BACKGROUND: Muscle atrophy is characterized by decreased muscle mass, function, and strength. Synthetic glucocorticoids, including dexamethasone (Dexa), are commonly used to treat autoimmune diseases. However, prolonged exposure of Dexa with high dose exerts severe side effects, including muscle atrophy. The purpose of this study was to investigate whether Gromwell root extract (GW) can prevent Dexa-induced muscle atrophy in C2C12 cells and mice and to characterize the composition of GW to identify bioactive compounds. METHODS: For in vitro experiments, GW (0.5 and 1 µg/mL) or lithospermic acid (LA, 5 and 10 µM) was added to C2C12 myotubes on day 4 of differentiation and incubated for 24 h, along with 50 µM Dexa. For in vivo experiment, four-week-old male C57BL/6 mice were randomly divided into the four following groups (n = 7/group): Con group, Dexa group, GW0.1 group, and GW0.2 group. Mice were fed experimental diets of AIN-93 M with or without 0.1 or 0.2% GW for 4 weeks. Subsequently, muscle atrophy was induced by administering an intraperitoneal injection of Dexa at a dose of 15 mg/kg/day for 38 days, in conjunction with dietary intake. RESULTS: In Dexa-induced myotube atrophy, treatment with GW increased myotube diameter, reduced the expression of muscle atrophy markers, and enhanced the expression of myosin heavy chain (MHC) isoforms in C2C12 cells. Supplementation with the GW improved muscle function and performance in mice with Dexa-induced muscle atrophy, evidenced in the grip strength and running tests. The GW group showed increased lean body mass, skeletal muscle mass, size, and myosin heavy chain isoform expression, along with reduced skeletal muscle atrophy markers in Dexa-injected mice. Supplementation with GW increased protein synthesis and decreased protein degradation through the Akt/mammalian target of rapamycin and glucocorticoid receptor/forkhead box O3 signaling pathways, respectively. We identified LA as a potential bioactive component of the GW. LA treatment increased myotube diameter and decreased the expression of muscle atrophy markers in Dexa-induced C2C12 cells. CONCLUSIONS: These findings underscore the potential of the GW in preventing Dexa-induced skeletal muscle atrophy and highlight the contribution of LA to its effects.
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Fuzhuan brick tea (FBT) is a post-fermented tea fermented by the fungus Eurotium cristatum and is mainly produced in Hunan Province, China. Our previous study revealed that FBT extract prevents obesity by increasing energy expenditure and mitochondrial content in mice. Therefore, in this study, we hypothesized that FBT extract could be effective in alleviating obesity-induced muscle atrophy by addressing mitochondrial dysfunction, and aimed to explore the underlying molecular mechanism of FBT extract in high-fat diet-induced obese mice. FBT extract increased skeletal muscle weight and size, myosin heavy chain isoforms, and muscle performance in obese mice. Additionally, FBT extract reduced obesity-induced intramuscular lipids, skeletal muscle inflammation, and the expression of skeletal muscle atrophy markers, and increased the expression of fibronectin type III domain-containing protein 5 in skeletal muscles. Obesity-induced skeletal muscle mitochondrial dysfunction was improved by FBT extract as analyzed through mitochondrial morphology, fatty acid oxidation, respiratory chain complexes, and mitochondrial dynamics and biogenesis. Epigallocatechin, a major bioactive compound in FBT extract, attenuated palmitic acid-induced muscle atrophy by regulating mitochondrial functions in C2C12 cells. In conclusion, FBT extract may prevent obesity-induced muscle atrophy by alleviating mitochondrial dysfunction in mice.
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Enfermedades Mitocondriales , Té , Ratones , Animales , Ratones Obesos , Obesidad/metabolismo , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/etiología , Atrofia Muscular/prevención & control , Músculo Esquelético/metabolismo , Extractos Vegetales/farmacologíaRESUMEN
BACKGROUND: Geniposide (GP) is an iridoid glycoside that is present in nearly 40 species, including Gardenia jasminoides Ellis. GP has been reported to exhibit neuroprotective effects in various Alzheimer's disease (AD) models; however, the effects of GP on AD models of Caenorhabditis elegans (C. elegans) and aging-accelerated mouse predisposition-8 (SAMP8) mice have not yet been evaluated. PURPOSE: To determine whether GP improves the pathology of AD and sarcopenia. METHODS: AD models of C. elegans and SAMP8 mice were employed and subjected to behavioral analyses. Further, RT-PCR, histological analysis, and western blot analyses were performed to assess the expression of genes and proteins related to AD and muscle atrophy. RESULTS: GP treatment in the AD model of C. elegans significantly restored the observed deterioration in lifespan and motility. In SAMP8 mice, GP did not improve cognitive function deterioration by accelerated aging but ameliorated physical function deterioration. Furthermore, in differentiated C2C12 cells, GP ameliorated muscle atrophy induced by dexamethasone treatment and inhibited FoxO1 activity by activating AKT. CONCLUSION: Although GP did not improve the AD pathology in SAMP8 mice, we suggest that GP has the potential to improve muscle deterioration caused by aging. This effect of GP may be attributed to the suppression of FoxO1 activity.
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Enfermedad de Alzheimer , Caenorhabditis elegans , Iridoides , Ratones , Animales , Enfermedad de Alzheimer/patología , Envejecimiento , Atrofia Muscular/tratamiento farmacológicoRESUMEN
The plant Justicia procumbens is traditionally used in Asia to treat fever, cough, and pain. Previous studies have reported its anticancer and anti-asthmatic properties. However, its potential for preventing androgenic alopecia (AGA) has not yet been reported. AGA is a widespread hair loss condition primarily caused by male hormones. In this study, we examined the hair loss-preventing effects of an aqueous extract of J. procumbens (JPAE) using human hair follicle dermal papilla cell (HFDPC) and a mouse model of testosterone-induced AGA. JPAE treatment increased HFDPC proliferation by activating the Wnt/ß-catenin signaling pathway. Additionally, JPAE increased the expression of Wnt targets, such as cyclin D1 and VEGF, by promoting the translocation of ß-catenin to the nucleus. Administration of JPAE reduced hair loss, increased hair thickness, and enhanced hair shine in an AGA mouse model. Furthermore, it increased the expression of p-GSK-3ß and ß-catenin in the dorsal skin of the mice. These findings imply that JPAE promotes the proliferation of HFDPC and prevents hair loss in an AGA mouse model. JPAE can therefore be used as a functional food and natural treatment option for AGA to prevent hair loss.
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Género Justicia , beta Catenina , Humanos , Ratones , Animales , beta Catenina/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Alopecia/inducido químicamente , Alopecia/prevención & control , Alopecia/metabolismo , Cabello/metabolismo , Vía de Señalización WntRESUMEN
The beneficial effects of Akkermansia muciniphila (Akk) on gut health and inflammation reduction have been demonstrated; however, scientific evidence of hair growth enhancement by Akk has not been reported. Therefore, this study was undertaken to investigate the effect of Akk on improving testosterone-mediated hair growth inhibition. Hair growth inhibition was induced through subcutaneous injection of testosterone into the shaved dorsal skin of C57BL/6 male mice. Live and pasteurized Akk were orally administered at a concentration of 1 × 108 colony-forming unit. After 5 weeks, hair length and skin tissues were analyzed. The live and pasteurized Akk significantly stimulated hair growth, countering the inhibitory effect of testosterone compared to the testosterone-alone group. Hematoxylin and eosin staining revealed a significant increase in hair follicle size in the Akk-treated group. An increase in ß-catenin levels, which are associated with hair growth and cell cycle progression, was also observed. Moreover, the Akk-treated group exhibited increased levels of fibroblast growth factors, including Fgf7, Igf1, Fgf7, Fgf10, and Fgf21. However, no significant difference was observed between the live and pasteurized Akk groups. These results underscore the potential of live and pasteurized Akk in improving testosterone-mediated hair growth inhibition.
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The share of the population that is aging is growing rapidly. In an aging society, technologies and interventions that delay the aging process are of great interest. Dietary restriction (DR) is the most reproducible and effective nutritional intervention tested to date for delaying the aging process and prolonging the health span in animal models. Preventive effects of DR on age-related diseases have also been reported in human. In addition, highly conserved signaling pathways from small animal models to human mediate the effects of DR. Recent evidence has shown that the immune system is closely related to the effects of DR, and functions as a major mechanism of DR in healthy aging. This review discusses the effects of DR in delaying aging and preventing age-related diseases in animal, including human, and introduces the molecular mechanisms that mediate these effects. In addition, it reports scientific findings on the relationship between the immune system and DRinduced longevity. The review highlights the role of immunity as a potential mediator of the effects of DR on longevity, and provides insights into healthy aging in human. [BMB Reports 2023; 56(10): 537-544].
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Restricción Calórica , Longevidad , Animales , Humanos , Envejecimiento , Transducción de Señal , DietaRESUMEN
Alopecia, regardless of gender, exacerbates psychological stress in those affected. The rising prevalence of alopecia has fueled a research interest in preventing hair loss. This study investigates the potential of millet seed oil (MSO) in promoting the proliferation of hair follicle dermal papilla cells (HFDPC) and stimulating hair growth in animals with testosterone-dependent hair growth inhibition as part of a study on dietary treatments to improve hair growth. MSO-treated HFDPC significantly increased cell proliferation and phosphorylation of AKT, S6K1, and GSK3ß proteins. This induces ß-catenin, a downstream transcription factor, to translocate to the nucleus and increase the expression of factors related to cell growth. In a C57BL/6 mice model in which hair growth was inhibited by subcutaneous testosterone injection after shaving the dorsal skin, oral administration of MSO stimulated hair growth in the subject mice by increasing the size and number of hair follicles. These results suggest that MSO is a potent agent that may help prevent or treat androgenetic alopecia by promoting hair growth.
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The human life span has been markedly extended since the 1900s, but it has not brought healthy aging to everyone. This increase in life expectancy without an increase in healthspan is a major global concern that imposes considerable health care budgets and degrades the quality of life of older adults. Dietary interventions are a promising strategy to increase healthspan. In this study, we evaluated whether a Gardenia jasminoides Ellis fruit ethanol extract (GFE) increases the life span of Caenorhabditis elegans (C. elegans). Treatment with 10 mg/mL GFE increased the life span by 27.1% when compared to the vehicle group. GFE (10 mg/mL) treatment improved healthspan-related markers (pharyngeal pumping, muscle quality, age-pigment, and reactive oxygen species accumulation) and exerted a protective effect against amyloid ßâ1-42 toxicity. These effects of GFE are related to the inhibition of insulin/IGF-1 signaling and activation of SKN-1/Nrf, thereby promoting the expression of stress resistance-related genes. In addition, treatment with 10 mM geniposide, the most abundant component of GFE, improved healthspan-related markers and increased life span by 18.55% when compared to the vehicle group. Collectively, these findings demonstrate that GFE and its component geniposide increase the life span along with healthspan in C. elegans.
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Proteínas de Caenorhabditis elegans , Gardenia , Animales , Humanos , Anciano , Caenorhabditis elegans , Frutas , Péptidos beta-Amiloides , Calidad de Vida , Proteínas de Caenorhabditis elegans/genética , LongevidadRESUMEN
Small GTPases are key signaling nodes that regulate the cellular processes and subcellular events, and their abnormal activities and dysregulations are closely linked with diverse cancers. Here, we report the development of conformation-selective protein binders for a KRAS mutant. The conformation-specific protein binders were selected from a repebody scaffold composed of LRR (Leucine-rich repeat) modules through phage display and modular engineering against constitute active conformation of KRAS. Epitope of the selected binders was mapped to be located close to switch I of KRAS. The conformation-selective protein binders were shown to effectively block the interaction between active KRAS and RAS-binding domain of BRAF, suppressing the KRAS-mediated downstream signaling.
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Neoplasias , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de Señal , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Dominios Proteicos , MutaciónRESUMEN
Dietary restriction (DR) is a highly effective and reproducible intervention that prolongs longevity in many organisms. The molecular mechanism of action of DR is tightly connected with the immune system; however, the detailed mechanisms and effective downstream factors of immunity that mediate the beneficial effects of DR on aging remain unknown. Here, to investigate the immune signaling that mediates DR effects, we used Caenorhabditis elegans, which has been widely used in research, to understand the underlying molecular mechanisms of aging and immunity. We found that the F-box gene, fbxc-58, a regulator of the innate immune response, is a novel mediator of DR effects on extending the health span of C. elegans. fbxc-58 is upregulated by DR and is necessary for DR-induced lifespan extension and physical health improvement in C. elegans. Furthermore, through DR, fbxc-58 prevents disintegration of the mitochondrial network in body wall muscle during aging. We found that fbxc-58 is a downstream target of the ZIP-2 and PHA-4 transcription factors, the well-known DR mediator, and fbxc-58 extends longevity in DR through an S6 kinase-dependent pathway. We propose that the novel DR effector, fbxc-58, could provide a new mechanistic understanding of the effects of DR on healthy aging and elucidate the signaling mechanisms that link immunity and DR effects with aging.
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Proteínas de Caenorhabditis elegans , Envejecimiento Saludable , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Restricción Calórica , Inmunidad Innata/fisiologíaRESUMEN
Codium fragile (C. fragile) is a marine alga with high functional food potential. Recent studies have proven C. fragile extract (CFE) effective against obesity. However, the exact underlying mechanism of CFE's anti-obesity effects remains unclear. Herein, CFE was orally administered to male C57BL/6 mice for 7 weeks, along with a high-fat diet. CFE (100 mg/kg) effectively induced weight loss, lowered serum cholesterol levels, and suppressed adipocyte differentiation in white adipose tissue (WAT). Furthermore, CFE effectively reduced hepatic total triglyceride, cholesterol, and lipid levels, while significantly improving liver size and color. mRNA expression analysis in WAT and liver tissue revealed that CFE significantly suppressed the expression of PPARγ and aP-2 in adipocyte differentiation, and SREBP-1c and FAS in de novo lipogenesis, suggesting that CFE's anti-obesity effect is exerted by gene inhibition. PRACTICAL APPLICATIONS: Research on marine plants with anti-obesity effects has been increasing recently. This study demonstrated that C. fragile extract (CFE) is effective in reducing body weight and suppressing adipocyte differentiation, along with the improvement of fatty liver in mice fed with a high-fat diet (HFD). The anti-obesity effect of CFE was exhibited by the down-regulation of adipogenesis and lipogenesis, respectively. Based on these results, C. fragile could be useful, not only to effectively combat obesity but also in improving obesity-induced liver dysfunction.
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Hígado Graso , Lipogénesis , Animales , Ratones , Incidencia , Ratones Endogámicos C57BL , Obesidad/tratamiento farmacológico , Obesidad/genética , ColesterolRESUMEN
Skeletal muscle atrophy is characterized by reduced muscle function and size. Oxidative stress contributes to muscle atrophy but can be treated with antioxidants. This study investigated the antioxidant activity of a castor oil plant leaf (Ricinus communis L.) extract (RC) and its effects on muscle atrophy. Rutin was identified as the major compound among the thirty compounds identified in RC via LC-MS/MS and was found to inhibit dexamethasone (DEX)-induced muscle atrophy and mitochondrial oxidative stress. Rutin-rich RC showed DPPH and ABTS radical scavenging activities and efficiently reduced the DEX-induced myotube atrophy and mitochondrial oxidative damage in C2C12 cells. RC supplementation prevented the loss of muscle function and muscle mass in DEX-administered mice and ameliorated DEX-induced oxidative stress via Nrf2 signaling. Taken together, both RC and rutin ameliorated muscle atrophy and helped in maintaining redox homeostasis; hence, rutin-rich RC could be a promising functional food that is beneficial for muscle health.
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Schisandra chinensis fruit (Omiza in Korean), used for the production tea or liquor, and is known to enhance skeletal muscle function. However, the effect of Omiza extract (OM) on obesity-induced skeletal muscle atrophy remains unclear. This study investigated the effect of OM on skeletal muscle mass and performance in obese mice. OM increased skeletal muscle weight, size and improved skeletal muscle performance. Further, it also suppressed obesity-induced increases in proinflammatory cytokines, MuRF1, and Atrogin1 in mouse skeletal muscle and enhanced the expression of MHC and the phosphorylation of AKT/mTOR signaling molecules, thereby suppressing myostatin expression and regulating Smad-FOXO signaling. Schizandrin B, a major component of OM inhibited palmitic acid induced atrophy in C2C12 cells via Smad-FOXO regulation, suggesting that it partially contributed to the effects of OM against obesity-induced muscle atrophy. Taken together, OM may have the potential to prevent and treat obesity-induced muscle atrophy.
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Schisandra , Animales , Ciclooctanos , Frutas/metabolismo , Lignanos , Ratones , Músculo Esquelético/metabolismo , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Atrofia Muscular/prevención & control , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Compuestos PolicíclicosRESUMEN
Skeletal muscle atrophy is defined as wasting or loss of muscle. Although glucocorticoids (GCs) are well-known anti-inflammatory drugs, their long-term or high-dose use induces skeletal muscle atrophy. Valeriana fauriei (VF) is used to treat restlessness, anxiety, and sleep disorders; however, its effects on skeletal muscle health have not been investigated. This study investigated whether Valeriana fauriei could ameliorate muscle atrophy. We induced muscle atrophy in vitro and in vivo, by treatment with dexamethasone (DEX), a synthetic GC. In DEX-induced myotube atrophy, Valeriana fauriei treatment increased the fusion index and decreased the expression of muscle atrophic genes such as muscle atrophy F-box (MAFbx/Atrogin-1) and muscle RING-finger protein 1 (MuRF1). In DEX-treated mice with muscle atrophy, Valeriana fauriei supplementation increased the ability to exercise, muscle weight, and cross-sectional area, whereas it inhibited myosin heavy chain isoform transition and the expression of muscle atrophy biomarkers. Valeriana fauriei treatment led to via the downregulation of muscle atrophic genes via inhibition of GC receptor translocation. Valeriana fauriei was also found to act as a reactive oxygen species (ROS) scavenger. Didrovaltrate (DI), an iridoid compound from Valeriana fauriei, was found to downregulate atrophic genes and decrease ROS in the DEX-induced myotube atrophy. Consolidated, our results indicate that Valeriana fauriei prevents DEX-induced muscle atrophy by inhibiting GC receptor translocation. Further, Valeriana fauriei acts as a ROS scavenger, and its functional compound is didrovaltrate. We suggest that Valeriana fauriei and its functional compound didrovaltrate possess therapeutic potentials against muscle atrophy.
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Antioxidantes/uso terapéutico , Dexametasona/efectos adversos , Glucocorticoides/efectos adversos , Atrofia Muscular/inducido químicamente , Atrofia Muscular/tratamiento farmacológico , Valeriana/química , Animales , Antioxidantes/farmacología , Humanos , Masculino , RatonesRESUMEN
BACKGROUND & AIMS: The development of nonalcoholic fatty liver disease (NAFLD) can be modulated by microRNAs (miRNA). Dietary polyphenols modulate the expression of miRNA such as miR-467b-3p in the liver. In addition, 6-gingerol (6-G), the functional polyphenol of ginger, has been reported to ameliorate hepatic steatosis; however, the exact mechanism involved and the role of miRNA remain elusive. In this study, we assessed the role of miR-467b-3p in the pathogenesis of hepatic steatosis and the regulation of miR-467b-3p by 6-G through the hepatocyte nuclear factor 4α (HNF4α). METHODS: miR-467b-3p expression was measured in free fatty acid (FFA)-treated hepatocytes or liver from high-fat diet (HFD)-fed mice. Gain- or loss-of-function of miR-467b-3p was induced using miR-467b-3p-specific miRNA mimic or miRNA inhibitor, respectively. 6-G was exposed to FFA-treated cells and HFD-fed mice. The HNF4α/miR-467b-3p/GPAT1 axis was measured in mouse and human fatty liver tissues. RESULTS: We found that miR-467b-3p was down-regulated in liver tissues from HFD-fed mice and in FFA-treated Hepa1-6 cells. Overexpression of miR-467b-3p decreased intracellular lipid accumulation in FFA-treated hepatocytes and mitigated hepatic steatosis in HFD-fed mice via negative regulation of glycerol-3-phosphate acyltransferase-1 (GPAT1). In addition, miR-467b-3p up-regulation by 6-G was observed. 6-G inhibited FFA-induced lipid accumulation and mitigated hepatic steatosis. Moreover, it increased the transcriptional activity of HNF4α, resulting in the increase of miR-467b-3p and subsequent decrease of GPAT1. HNF4α/miR-467b-3p/GPAT1 signaling also was observed in human samples with hepatic steatosis. CONCLUSIONS: Our findings establish a novel mechanism by which 6-G improves NAFLD. This suggests that targeting of the HNF4α/miR-467b-3p/GPAT1 cascade may be used as a potential therapeutic strategy to control NAFLD.
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1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , Catecoles/farmacología , Alcoholes Grasos/farmacología , Regulación de la Expresión Génica/genética , Factor Nuclear 4 del Hepatocito/genética , MicroARNs/genética , Interferencia de ARN , Animales , Modelos Animales de Enfermedad , Expresión Génica , Genes Reporteros , Factor Nuclear 4 del Hepatocito/química , Humanos , Metabolismo de los Lípidos , Masculino , Ratones , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Relación Estructura-ActividadRESUMEN
SCOPE: γ-Oryzanol, a well-known antioxidant, has been used by body builders and athletes to boost strength and increase muscle gain, without major side effects. However, the effect of γ-Oryzanol on sarcopenia and the underlying molecular mechanism is poorly understood. RESULTS: Aged mice fed with the γ-Oryzanol diet do not show significant changes in muscle weight, but show increased running endurance as well as improved grip strength. The expression and activity of PPARδ and ERRγ are increased in skeletal muscle of γ-Oryzanol supplemented mice. γ-Oryzanol upregulates oxidative muscle fibers by MEF2 transcription factor, and PGC-1α and ERRα expressions. Fatty acid oxidation related genes and mitochondria biogenesis are upregulated by γ-Oryzanol. In addition, γ-Oryzanol inhibits TGF-ß-Smad-NADPH oxidase 4 pathway and inflammatory cytokines such as TNF-α, IL-1ß, IL-6, and p65 NF-κB subunit, which cause skeletal muscle weakness. Collectively, γ-Oryzanol attenuates muscle weakness pathway and increases oxidative capacity by increasing PPARδ and ERRγ activity, which contributes to enhance strength and improve oxidative capacity in muscles, consequently enhancing exercise capacity in aged mice. Particularly, γ-Oryzanol directly binds to PPARδ. CONCLUSIONS: These are the first findings showing that γ-Oryzanol enhances skeletal muscle function in aged mice by regulating PPARδ and ERRγ activity without muscle gain.
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Envejecimiento , PPAR delta/metabolismo , Fenilpropionatos/farmacología , Condicionamiento Físico Animal , Receptores de Estrógenos/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias Musculares , Fuerza Muscular , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Biogénesis de Organelos , Resistencia Física , Receptor Relacionado con Estrógeno ERRalfaRESUMEN
Codium fragile (CF) is a type of green algae consumed as kimchi in Asia. UPLC-QTOF-MS/MS analysis showed that CF contain lysophosphatidyl choline, canthaxanthin, retinoic acid, α-tocopherol, and unsaturated fatty acids, which reportedly improve skeletal muscle health. However, the effect of CF on skeletal muscle mass and function remains to be elucidated. In mice fed with CF extracts, exercise endurance and muscle weight increased. CF extracts enhanced protein synthesis and myogenic differentiation through the mTORC1 pathway. CF extracts also promoted oxidative muscle fiber formation and mitochondrial biogenesis through the PGC-1α-related signaling pathway. Upregulation of PGC-1α by CF extracts was abolished by EX527 SIRT1 inhibitor treatment. Changed signaling molecules in the CF extracts were partially regulated by canthaxanthin, a new compound in CF extracts, suggesting that canthaxanthin contribute synergistically to the effect of CF extracts. Therefore, CF is a potential food source for sport nutrition or prevention of sarcopenia.
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Chlorophyta/química , Músculo Esquelético/efectos de los fármacos , Resistencia Física/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Cantaxantina/análisis , Carbazoles/farmacología , Masculino , Ratones Endogámicos C57BL , Músculo Esquelético/fisiología , Tamaño de los Órganos/efectos de los fármacos , Biogénesis de Organelos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Condicionamiento Físico Animal/fisiología , Resistencia Física/fisiología , Extractos Vegetales/análisis , Algas Marinas/química , Transducción de Señal/efectos de los fármacos , Espectrometría de Masas en Tándem , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Post-menopausal conditions exacerbate the biological aging process and this is often accompanied by visceral adiposity with sarcopenia. Mitochondrial impairment is a hallmark of frailty and sarcopenia in the elderly. However, the exact mechanism underlying the development of obesogenic sarcopenia and the involvement of mitochondria remains unclear. This study confirmed that there is a decline in muscle mass and function as well as mitochondrial dysfunction in the quadriceps of ovariectomized (OVX) mice. To investigate the role of microRNA (miRNA) in this process, we performed miRNA and mRNA arrays and found that miR-141-3p directly targets and downregulates FK506 binding protein 5 (Fkbp5) and Fibin. Overexpression of miR-141-3p decreased mitochondrial function and inhibited myogenic differentiation in C2C12 cells. These effects were mediated by Fkbp5 and Fibin inhibition. Conversely, knockdown of miR-141-3p increased mitochondrial respiration and enhanced myogenesis. Treatment with ß-estradiol effectively reversed the palmitic acid-induced upregulation of miR-141-3p and subsequent downregulation of Fkbp5 and Fibin. In conclusion, miR-141-3p is upregulated in OVX mice, and this is associated with mitochondrial dysfunction through inhibition of Fkbp5 and Fibin. These findings suggest that inhibiting miR-141-3p could be a therapeutic target for alleviating obesogenic sarcopenia.