Korean Red Ginseng-Induced SIRT3 Promotes the Tom22-HIF-1α Circuit in Normoxic Astrocytes.

Astrocytes play a key role in brain functioning by providing energy to neurons. Increased astrocytic mitochondrial functions by Korean red ginseng extract (KRGE) have been investigated in previous studies. KRGE administration induces hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in astrocytes in the adult mouse brain cortex. VEGF expression can be controlled by transcription factors, such as the HIF-1α and estrogen-related receptor α (ERRα). However, the expression of ERRα is unchanged by KRGE in astrocytes of the mouse brain cortex. Instead, sirtuin 3 (SIRT3) expression is induced by KRGE in astrocytes. SIRT3 is a nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase that resides in the mitochondria and maintains mitochondrial homeostasis. Mitochondrial maintenance requires oxygen, and active mitochondria enhance oxygen consumption, resulting in hypoxia. The effects of SIRT3 on HIF-1α-mediated mitochondria functions induced by KRGE are not well established. We aimed to investigate the relationship between SIRT3 and HIF-1α in KRGE-treated normoxic astrocyte cells. Without changing the expression of the ERRα, small interfering ribonucleic acid targeted for SIRT3 in astrocytes substantially lowers the amount of KRGE-induced HIF-1α proteins. Reduced proline hydroxylase 2 (PHD2) expression restores HIF-1α protein levels in SIRT3-depleted astrocytes in normoxic cells treated with KRGE. The translocation of outer mitochondrial membranes 22 (Tom22) and Tom20 is controlled by the SIRT3-HIF-1α axis, which is activated by KRGE. KRGE-induced Tom22 increased oxygen consumption and mitochondrial membrane potential, as well as HIF-1α stability through PHD2. Taken together, in normoxic astrocytes, KRGE-induced SIRT3 activated the Tom22-HIF-1α circuit by increasing oxygen consumption in an ERRα-independent manner.

Flavonoids: nutraceutical potential for counteracting muscle atrophy.

Skeletal muscle plays a vital role in the conversion of chemical energy into physical force. Muscle atrophy, characterized by a reduction in muscle mass, is a symptom of chronic disease (cachexia), aging (sarcopenia), and muscle disuse (inactivity). To date, several trials have been conducted to prevent and inhibit muscle atrophy development; however, few interventions are currently available for muscle atrophy. Recently, food ingredients, plant extracts, and phytochemicals have received attention as treatment sources to prevent muscle wasting. Flavonoids are bioactive polyphenol compounds found in foods and plants. They possess diverse biological activities, including anti-obesity, anti-diabetes, anti-cancer, anti-oxidation, and anti-inflammation. The effects of flavonoids on muscle atrophy have been investigated by monitoring molecular mechanisms involved in protein turnover, mitochondrial activity, and myogenesis. This review summarizes the reported effects of flavonoids on sarcopenia, cachexia, and disuse muscle atrophy, thus, providing an insight into the understanding of the associated molecular mechanisms.

Inhibitory Effects of Standardized Leonurus japonicus Extract and Its Bioactive Leonurine on TNF-α-Induced Muscle Atrophy in L6 Myotubes.

Muscle atrophy, characterized by a reduced number and size of myofibers, occurs due to immobilization, aging, and several chronic diseases. Leonurus japonicus, belonging to the Labiatae family, is widely used as a traditional medicine in Korea, China, and Japan. Previous studies have reported that L. japonicus has various physiological activities, such as anti-bacteria, anti-cancer, and liver protection. Leonurine, which is a major bioactive in L. japonicas, is known to possess biological effects including anti-inflammation, anti-fibrosis, anti-angiogenesis, and anti-diabetes. However, the preventive effects of L. japonicas and leonurine on muscle have not been reported. The current study aimed to determine the inhibitory effects of standardized L. japonicus extract (LJE) and leonurine on muscle atrophy by clarifying their underlying molecular mechanisms in tumor necrosis factor-alpha (TNF-α)-stimulated L6 myotubes. LJE and leonurine stimulated the phosphatidylinositol 3-kinase/Akt pathway that was reduced by TNF-α treatment. LJE and leonurine not only increased the mammalian target of rapamycin pathway for protein anabolism but also decreased the mRNA expression of E3 ubiquitin ligases by blocking the translocation of Forkhead box O, which is closely linked with proteolysis. Additionally, LJE and leonurine alleviated inflammatory responses by downregulating TNF-α and interleukin-6 mRNA expression and reducing the protein expression of nuclear factor-kappa B, a major transcriptional factor of proinflammatory cytokines. Collectively, LJE and leonurine have potential as therapeutic candidates for inhibiting the development of skeletal muscle atrophy by activating the PI3K/Akt pathway and reducing inflammatory responses.

The 5,7-Dimethoxyflavone Suppresses Sarcopenia by Regulating Protein Turnover and Mitochondria Biogenesis-Related Pathways.

Sarcopenia is a muscle disease featured by the loss of muscle mass and dysfunction with advancing age. The 5,7-dimethoxyflavone (DMF), a major flavone found in Kaempferia parviflora, has biological activities, including anti-diabetes, anti-obesity, and anti-inflammation. However, its anti-sarcopenic effect remains to be elucidated. This current study investigated the inhibitory activity of DMF on sarcopenia. Eighteen-month-old mice were orally administered DMF at the dose of 25 mg·kg-1·day-1 or 50 mg·kg-1·day-1 for 8 weeks. DMF not only stimulated grip strength and exercise endurance but also increased muscle mass and volume. Besides, DMF stimulated the phosphatidylinositol 3-kinase-Akt pathway, consequently activating the mammalian target of rapamycin-eukaryotic initiation factor 4E-binding protein 1-70-kDa ribosomal protein S6 kinase pathway for protein synthesis. DMF reduced the mRNA expression of E3 ubiquitin ligase- and autophagy-lysosomal-related genes involved in proteolysis via the phosphorylation of Forkhead box O3. DMF upregulated peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, nuclear respiratory factor 1, and mitochondrial transcription factor A along with the increase of relative mitochondrial DNA content. DMF alleviated inflammatory responses by reducing the tumor necrosis factor-alpha and interleukin-6 serum and mRNA levels. Collectively, DMF can be used as a natural agent to inhibit sarcopenia via improving protein turnover and mitochondria function.

Estimation of an Appropriate Human Dose of Boesenbergia pandurata Extracts Based on Allometric Scaling Data of Panduratin A in Mice, Rats, and Dogs.

It can be difficult to identify health/functional foods that exert therapeutic benefits for alleviating gingivitis and periodontitis. Recently, extracts of Boesenbergia pandurata (Roxb.), which is a tropical plant, have shown promising inhibitory activity against lipopolysaccharide-induced periodontitis. As a result, a clinical trial is being planned to assess utility of B. pandurata (Roxb.) extracts for promoting oral health; this study was designed to determine an appropriate human dose of the extracts for the trial. Pharmacokinetic studies of panduratin A, which is an active substance in fingerroot, were carried out in mice, rats, and dogs after oral administration of the extracts. The clearance data for each species were used to estimate clearance in humans through allometric scaling based on the maximum lifespan potential, and a daily dose providing sufficient anti-periodontitis activity was estimated for use in the clinical trial. The findings indicated that allometric scaling is a reasonable approach that is relatively free of safety issues and can be used to determine doses of substances for incorporation into health/functional foods appropriate for humans.

Red Bean Extract Inhibits Immobilization-Induced Muscle Atrophy in C57BL/6N Mice.

Muscle atrophy, which is characterized by a decrease in muscle mass, function, and protein content, can be caused by aging, disease, and physical inactivity. Red bean or Adzuki bean (Vigna angularis) has been consumed as an edible legume. Red bean possesses various functional properties, such as antidiabetes, antiaging, anti-inflammatory, anticancer, and hepatoprotective activities. However, little is known about its potential inhibitory effect on muscle atrophy. In this study, we investigated the inhibitory effect of red bean extract (RBE) on muscle atrophy in an immobilized hindlimb muscle of C57BL/6J mice. RBE dose-dependently increased grip strength, exercise endurance, muscle weight, and myofiber area. At the molecular level, RBE significantly reduced the mRNA expression of proteolysis-related genes, such as muscle ring finger and muscle atrophy F-box by preventing the translocation of Forkhead box 3. RBE also activated the phosphatidylinositol 3 kinase/Akt pathway, subsequently stimulating the mammalian target of rapamycin/70-kDa ribosomal protein S6 kinase/eukaryotic initiation factor 4E binding protein 1 pathway involved in protein synthesis. Overall, red bean could be used as a functional food ingredient or therapeutic agent to inhibit muscle atrophy.

Standardized Siegesbeckia orientalis L. Extract Increases Exercise Endurance Through Stimulation of Mitochondrial Biogenesis.

Siegesbeckia orientalis has been reported to exhibit anti-allergic, anti-infertility, anti-inflammatory, anti-rheumatic, and immunosuppressive activities. However, there are very few studies describing its stimulatory effects on exercise capacity. This study elucidated whether S. orientalis extract (SOE) standardized to kirenol content can enhance exercise endurance by increasing mitochondrial biogenesis. SOE significantly improved the running distance and time in mice fed normal diet (ND) and high-fat diet (HFD). SOE also enhanced mitochondrial biogenesis by stimulating the mitochondrial regulatory genes including peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α), estrogen-related receptor α (ERRα), nuclear respiratory factor 1 (NRF-1), and mitochondrial transcription factor A (TFAM) in the skeletal muscles of ND and HFD mice. Furthermore, SOE upregulated the AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1)/PGC-1α/peroxisome proliferator-activated receptor delta (PPARδ) signaling pathway in the skeletal muscles of ND and HFD mice. Kirenol markedly increased adenosine triphosphate production and mitochondrial activity by stimulating the expression of markers of mitochondrial biogenesis and upregulating the AMPK/SIRT1/PGC-1α/PPARδ signaling pathway in L6 myotubes. These results show that SOE has the potential to be used to develop an exercise supplement capable of stimulating mitochondrial biogenesis through the AMPK/SIRT1/PGC-1α/PPARδ signaling pathway.

Agastache rugosa Kuntze Attenuates UVB-Induced Photoaging in Hairless Mice through the Regulation of MAPK/AP-1 and TGF-ß/ Smad Pathways.

Chronic exposure to ultraviolet (UV) radiation, regarded as a major cause of extrinsic aging or photoaging characterized by wrinkle formation and skin dehydration, exerts adverse effects on skin by causing the overproduction of reactive oxygen species. Agastache rugosa Kuntze, known as Korean mint, possesses a wide spectrum of biological properties including antioxidation, anti-inflammation, and anti-atherosclerosis. Previous studies have reported that A. rugosa protected human keratinocytes against UVB irradiation by restoring the anti-oxidant defense system. However, the anti-photoaging effect of A. rugosa extract (ARE) in animal models has not yet been evaluated. ARE was orally administered to hairless mice at doses of 100 or 250 mg/kg/day along with UVB exposure for 12 weeks. ARE histologically improved UVB-induced wrinkle formation, epidermal thickening, erythema, and hyperpigmentation. In addition, ARE recovered skin moisture by improving skin hydration and transepidermal water loss (TEWL). Along with this, ARE increased hyaluronic acid levels by upregulating HA synthase genes. ARE markedly increased the density of collagen and the amounts of hydroxypoline via two pathways. First, ARE significantly downregulated the mRNA expression of matrix metalloproteinases responsible for collagen degradation by inactivating the mitogen-activated protein kinase/activator protein 1 pathway. Second, ARE stimulated the transforming growth factor beta/Smad signaling, consequently raising the mRNA levels of collagen-related genes. In addition, ARE not only increased the mRNA expression of antioxidant enzymes but also decreased inflammatory cytokines by blocking the protein expression of nuclear factor kappa B. Collectively, our findings suggest that A. rugosa may be a potential preventive and therapeutic agent for photoaging.

Inhibitory Effect of Standardized Curcuma xanthorrhiza Supercritical Extract on LPS-Induced Periodontitis in Rats.

Periodontitis, which is a severe inflammatory disease caused by endotoxins secreted from oral pathogens, destructs gingival tissue and alveolar bone. Curcuma xanthorrhiza, commonly called Java turmeric, has been shown to possess anti-bacterial and anti-inflammatory activities. The present study evaluated the inhibitory effect of C. xanthorrhiza supercritical extract (CXS) standardized with xanthorrhizol on lipopolysaccharide (LPS)-induced periodontitis in an animal model. LPS was topically injected into the periodontium of Sprague-Dawley rats to induce periodontitis and CXS (30 and 100 mg·kg-1·day-1) was orally administered after day 12. Histologically, CXS inhibited the collapse of gingival tissue by preventing cell infiltration. CXS significantly downregulated the expression of matrix metalloproteases (MMPs) and inflammation-related biomarkers, such as nuclear factor-kappa B (NF-κB) and interleukin-1 beta (IL-1ß) in gingival tissue. CXS also improved bone remodeling by downregulating osteoclastic transcription factors, such as nuclear factor of activated T-cells c1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K. In addition, CXS upregulated osteoblast differentiation-related markers, alkaline phosphate (ALP) and collagen type I alpha (COLA1). Thus, CXS can ameliorate periodontitis by inhibiting inflammation and improving bone remodeling.

Inhibitory Effects of Standardized Boesenbergia pandurata Extract and Its Active Compound Panduratin A on Lipopolysaccharide-Induced Periodontal Inflammation and Alveolar Bone Loss in Rats.

Periodontitis, an inflammatory disease of the gingival tissue, triggered by microbial-derived elements, such as lipopolysaccharide (LPS), collapses the periodontal tissues and resorbs the alveolar bone. This study evaluated the inhibitory effects of standardized Boesenbergia pandurata extract (BPE) and panduratin A (PAN) on periodontitis-induced inflammation and alveolar bone loss. Sprague-Dawley rats with LPS-induced periodontitis were orally administered BPE (50 and 200 mg/kg/day) and PAN (20 mg/kg/day) for 8 days. Histological analysis revealed that BPE- and PAN-administered groups showed decreased cell infiltration and alveolar bone resorption. Furthermore, the BPE and PAN significantly alleviated the mRNA and protein expression levels of nuclear factor kappa B (NF-κB), interleukin-1ß, matrix metalloproteinase (MMP)-2, and MMP-8. BPE and PAN also inhibited the expression of nuclear factor of activated T cells, cytoplasmic 1, c-Fos, and ostoclastogenesis-related enzymes, including cathepsin K and tartrate-resistant acid phosphatase (ALP). BPE and PAN not only upregulated the osteoblastogenesis-associated markers, such as collagen type I (COL1A1) and ALP, but also increased the ratio of osteoprotegerin to receptor activator of NF-κB ligand. Collectively, BPE and PAN efficiently prevent destruction of periodontal tissues and stimulating the loss of alveolar bone tissues, strongly indicative of their potential as natural antiperiodontitis agents.

Inhibitory Effects of Curcuma xanthorrhiza Supercritical Extract and Xanthorrhizol on LPS-Induced Inflammation in HGF-1 Cells and RANKL-Induced Osteoclastogenesis in RAW264.7 Cells.

Periodontal disease is triggered by the host immune response to pathogens in the microbial biofilm. Worsening of periodontal disease destroys the tooth-supporting tissues and alveolar bone. As oral inflammation can induce systemic diseases in humans, it is important to prevent periodontal disease. In this study, we demonstrated that Curcuma xanthorrhiza supercritical extract (CXS) and its active compound, xanthorrhizol (XAN), exhibit anti-inflammatory effects on lipopolysaccharide (LPS)-treated human gingival fibroblast-1 cells and anti-osteoclastic effects on receptor activator of nuclear factor kappa B ligand (RANKL)-treated RAW264.7 cells. LPS-upregulated inflammatory factors, such as nuclear factor kappa B p65 and interleukin-1ß, were prominently reduced by CXS and XAN. In addition, RANKL-induced osteoclastic factors, such as nuclear factor of activated T-cells c1, tartrate-resistant acid phosphatase, and cathepsin K, were decreased in the presence of CXS and XAN. CXS and XAN inhibited the mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1) signaling pathway. Collectively, these results provide evidence that CXS and XAN suppress LPS-induced inflammation and RANKL-induced osteoclastogenesis by suppressing the MAPK/AP-1 pathway.

Standardized Kaempferia parviflora Wall. ex Baker (Zingiberaceae) Extract Inhibits Fat Accumulation and Muscle Atrophy in ob/ob Mice.

Obesity, a metabolic disorder caused by an imbalance between energy intake and energy expenditure, is accompanied with fat accumulation and skeletal muscle atrophy. Kaempferia parviflora Wall. ex Baker, also called black ginger, is known to increase physical fitness performance and improve energy metabolism. In this study, we investigated whether Kaempferia parviflora extract (KPE) alleviates both obesity and muscle atrophy using ob/ob mice. Wild-type C57BL/6J and ob/ob mice were provided with a normal diet ad libitum, and ob/ob mice were orally given KPE at a dose of 100 mg/kg/day or 200 mg/kg/day for eight weeks. KPE significantly decreased body weight, fat volume, and fat weight without affecting appetite. It inhibited the expression of adipogenic transcription factors and lipogenic enzymes by upregulating AMP-activated protein kinase (AMPK) in epididymal fat. In contrast, it markedly increased the muscle fiber size, muscle volume, and muscle mass, resulting in the enhancement of muscle function, such as exercise endurance and grip strength. On the molecular level, it activated the phosphatidylinositol 3 kinase (PI3K)/Akt pathway, a key regulator in protein synthesis in skeletal muscle. KPE could be a promising material to alleviate obesity by inhibiting adipogenesis, lipogenesis, and muscle atrophy.

Piper retrofractum Vahl. Extract, as a PPARδ and AMPK Activator, Suppresses UVB-Induced Photoaging through Mitochondrial Biogenesis and MMPs Inhibition in Human Dermal Fibroblasts and Hairless Mice.

Photoaging occurs by UVB-irradiation and involves production of reactive oxygen species (ROS) and overexpression of matrix metalloproteinases (MMPs), leading to extracellular matrix damage. Piper retrofractum Vahl. is used as a traditional medicine for antiflatulence, expectorant, sedative, and anti-irritant; however, its antiphotoaging effect has not yet been studied. The current study investigated the antiphotoaging effect of standardized Piper retrofractum extract (PRE) on UVB-damaged human dermal fibroblasts and hairless mouse skin. PRE treatment activated the peroxisome proliferator-activated receptor delta (PPARδ) and the adenosine monophosphate-activated protein kinase (AMPK), consequently upregulating mitochondrial synthesis and reducing ROS production. Additionally, PRE inhibited MMPs expression via suppressing mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1). PRE downregulated UVB-induced inflammatory reactions by inhibiting the nuclear factor-kappa B (NF-κB) activity. PRE also enhanced transforming growth factor-beta (TGF-ß) and the Smad signaling pathway, thereby promoting procollagen gene transcription. Furthermore, oral administration of PRE (300 mg/kg/day) similarly regulated the signaling pathways and increased antioxidant enzyme expression, thus attenuating physiological deformations, such as wrinkle formation and erythema response. Collectively, these results suggest that PRE acts as a potent antiphotoaging agent via PPARδ and AMPK activation.

Inhibitory Effects of Boesenbergia pandurata on Age-Related Periodontal Inflammation and Alveolar Bone Loss in Fischer 344 Rats.

Periodontitis, an infective disease caused by oral pathogens and the intrinsic aging process, results in the destruction of periodontal tissues and the loss of alveolar bone. This study investigated whether Boesenbergia pandurata extract (BPE) standardized with panduratin A exerted anti-periodontitis effects, using an aging model representative of naturally occurring periodontitis. In aged rats, the oral administration of BPE (200 mg·kg-1·day-1) for 8 weeks significantly reduced the mRNA and protein expression of interleukin-1ß, nuclear factor-kappa B, matrix metalloproteinase (MMP)-2, and MMP-8 in gingival tissues (p < 0.01). In alveolar bone, histological analysis with staining and micro-computed tomography revealed the attenuation of alveolar bone resorption in the BPE-treated aged group, which led to a significant reduction in the mRNA and protein expression of nuclear factor of activated T-cells c1 (NFATc1), c-Fos, tartrate-resistant acid phosphatase, and cathepsin K (p < 0.01). BPE not only increased the expression of osteoblast differentiation markers, such as alkaline phosphate, and collagen type I (COL1A1), but also increased the ratio of osteoprotegerin to RANKL. Collectively, the results strongly suggested that BPE is a natural resource for the prevention or treatment of periodontal diseases.

Inhibitory Effects of Panduratin A on Periodontitis-Induced Inflammation and Osteoclastogenesis through Inhibition of MAPK Pathways In Vitro.

Periodontitis is an inflammatory disease caused by microbial lipopolysaccharide (LPS), destroying gingival tissues and alveolar bone in the periodontium. In the present study, we evaluated the anti-inflammatory and anti-osteoclastic effects of panduratin A, a chalcone compound isolated from Boesenbergia pandurata, in human gingival fibroblast-1 (HGF-1) and RAW 264.7 cells. Treatment of panduratin A to LPS-stimulated HGF-1 significantly reduced the expression of interleukin-1ß and nuclear factor-kappa B (NF-κB), subsequently leading to the inhibition of matrix metalloproteinase-2 (MMP-2) and MMP-8 compared with that in the LPS control (**p < 0.01). These anti-inflammatory responses were mediated by suppressing the mitogen-activated protein kinase (MAPK) signaling and activator protein-1 complex formation pathways. Moreover, receptor activator of NF-κB ligand (RANKL)-stimulated RAW 264.7 cells treated with panduratin A showed significant inhibition of osteoclastic transcription factors such as nuclear factor of activated T-cells c1 and c-Fos as well as osteoclastic enzymes such as tartrate-resistant acid phosphatase and cathepsin K compared with those in the RANKL control (**p < 0.01). Similar to HGF-1, panduratin A suppressed osteoclastogenesis by controlling MAPK signaling pathways. Taken together, these results suggest that panduratin A could be a potential candidate for development as a natural anti-periodontitis agent.

Standardized Kaempferia parviflora Extract Enhances Exercise Performance Through Activation of Mitochondrial Biogenesis.

Exercise enhances mitochondrial biogenesis in skeletal muscle. Increased mitochondrial function and content can contribute to the improvement in skeletal muscle function and the benefits of exercise by increasing the response to energy demands. The effect of standardized Kaempferia parviflora extract (KPE) on exercise performance was accessed in L6 myotubes and C57BL/6J mice. KPE significantly activated peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and increased mitochondrial density in L6 myotubes. KPE also upregulated the expression of transcription factors for mitochondrial biogenesis (estrogen-related receptor-α [ERRα], nuclear respiratory factor-1 [NRF-1], and mitochondrial transcription factor A [Tfam]) through activation of PGC-1α in L6 myotubes. In vivo models including normal diet mice and high-fat diet obese mice showed that KPE effectively enhanced running endurance and increased the skeletal muscle weight/body weight ratio. Furthermore, these observations were associated with a significant upregulation of mitochondrial biogenesis regulatory genes in skeletal muscle tissue. KPE enhanced the protein expression of the sirtuin 1 (SIRT1)/adenosine monophosphate (AMP)-activated protein kinase (AMPK)/PGC-1α/peroxisome proliferator-activated receptor-δ (PPARδ) signaling pathway components in vitro and in vivo, acting as an exercise metabolism regulator. These results suggest that KPE has the potential to enhance exercise performance through mitochondrial biogenesis and the SIRT1/AMPK/PGC-1α/PPARδ signaling pathways.

Panduratin A Prevents Tumor Necrosis Factor-Alpha-Induced Muscle Atrophy in L6 Rat Skeletal Muscle Cells.

Panduratin A, a prenylated chalcone compound, has anti-obesity, anti-bacterial, anti-cancer, anti-inflammatory, and anti-oxidative activities. However, its preventive effect on muscle atrophy has not been studied. The purpose of this study was to evaluate the inhibitory effect of panduratin A on muscle atrophy and to investigate its molecular mechanisms in tumor necrosis factor-alpha (TNF-α)-treated L6 rat skeletal muscle cells. Panduratin A restored the myotube diameter reduced by TNF-α. At the molecular level, panduratin A elevated phosphatidylinositol 3 kinase/Akt/mammalian target of rapamycin pathway and stimulated the MyoD and myogenin mRNA expression decreased by TNF-α. However, panduratin A attenuated the mRNA expression of E3 ubiquitin ligase and autophagy-related genes. Moreover, panduratin A significantly inhibited reactive oxygen species production by increasing the mRNA expression of catalase and superoxide dismutase. Overall, panduratin A might be a useful agent for the treatment of muscle atrophy.

Standardized Kaempferia parviflora Extract Inhibits Intrinsic Aging Process in Human Dermal Fibroblasts and Hairless Mice by Inhibiting Cellular Senescence and Mitochondrial Dysfunction.

Intrinsic skin aging is a complex biological phenomenon mainly caused by cellular senescence and mitochondrial dysfunction. This study evaluated the inhibitory effect of Kaempferia parviflora Wall ex. Baker ethanol extract (KPE) on H2O2-stimulated cellular senescence and mitochondrial dysfunction both in vitro and in vivo. KPE significantly increased cell growth and suppressed senescence-associated ß-galactosidase activation. KPE inhibited the expression of cell-cycle inhibitors (p53, p21, p16, and pRb) and stimulated the expression of cell-cycle activators (E2F1 and E2F2). H2O2-induced hyperactivation of the phosphatidylinositol 3-kinase/protein kinase B (AKT) signaling pathway was suppressed by KPE through regulated expression of forkhead box O3a (FoxO3a) and mammalian target of rapamycin (mTOR). KPE attenuated inflammatory mediators (interleukin-6 (IL-6), IL-8, nuclear factor kappa B (NF-κB), and cyclooxygenase-2 (COX-2)) and increased the mRNA expression of PGC-1α, ERRα, NRF1, and Tfam, which modulate mitochondrial biogenesis and function. Consequently, reduced ATP levels and increased ROS level were also reversed by KPE treatment. In hairless mice, KPE inhibited wrinkle formation, skin atrophy, and loss of elasticity by increasing the collagen and elastic fibers. The results indicate that KPE prevents intrinsic aging process in hairless mice by inhibiting cellular senescence and mitochondrial dysfunction, suggesting its potential as a natural antiaging agent.

Oral intake of Boesenbergia pandurata extract improves skin hydration, gloss, and wrinkling: A randomized, double-blind, and placebo-controlled study.

BACKGROUND: Photoaging is a severe skin damage that occurs as a result of exposure to external elements, primarily ultraviolet (UV) irradiation. Chronically, UV-irradiated skin exhibits the signs of sunburn and hyperpigmentation with the destruction of connective tissues. Previously, Boesenbergia pandurata (B. pandurata) and its active compound panduratin A showed antiphotoaging activities in vitro and in vivo. OBJECTIVE: The aim of this study was to investigate the clinical efficacy of B. pandurata intake on skin hydration, gloss, wrinkling, and elasticity. METHODS: A double-blind, placebo-controlled trial was conducted to clinically evaluate the effect of B. pandurata ethanol extract (BPE) containing 8% of panduratin A on human skin hydration, gloss, wrinkling, and elasticity. Ninety-two subjects were randomly assigned to receive tablets containing either BPE or placebo for 12 weeks. RESULTS: The test group had significantly increased skin hydration and gloss and decreased wrinkling compared to the placebo group at 12 weeks. There was no significant difference in skin elasticity between the two groups; however, the increment rate in the test group was higher than that in the placebo group at 12 weeks. None of the subjects developed adverse symptoms during the study period. CONCLUSION: These results suggest that BPE can be used as a nutraceutical or nutricosmetic material for improving human skin hydration, gloss, and wrinkling.

5,7-Dimethoxyflavone Attenuates Obesity by Inhibiting Adipogenesis in 3T3-L1 Adipocytes and High-Fat Diet-Induced Obese C57BL/6J Mice.

The antiobesity effect of 5,7-dimethoxyflavone (DMF) was evaluated in 3T3-L1 adipocytes and high-fat diet (HFD)-induced obese C57BL/6J mice. The accumulation of lipid droplets and triglycerides in adipocytes was dose dependently suppressed by DMF through inhibition of adipogenesis. DMF downregulated the adipogenic transcription factors (peroxisome proliferator-activated receptor [PPAR]γ, CCAAT/enhancer binding protein [C/EBP]α, and sterol regulatory element-binding protein-1c [SREBP-1c]) and lipid synthesis enzymes (fatty acid synthase [FAS], acetyl-CoA carboxylase [ACC], lipoprotein lipase [LPL], and HMG-CoA reductase [HMGR]). AMP-activated protein kinase (AMPK) and AMPK related lipolytic proteins in differentiated adipocytes were activated by DMF. In the animal model, oral administration of DMF (50 mg/kg/day for 6 weeks) significantly decreased body weight gain without affecting food intake. Elevated serum levels of total cholesterol and low-density lipoprotein cholesterol were suppressed by DMF. Fat pad masses were reduced in DMF-treated obese mice, as evidenced by reduced adipocyte size. DMF altered the expression of adipogenic transcription factors in epididymal fat tissue. In addition, DMF attenuated HFD-induced nonalcoholic fatty liver disease by decreasing hepatic triglyceride accumulation. Overall, these results suggest that DMF is a potential natural agent for attenuating obesity and other obesity-related metabolic syndromes.