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Acer tegmentosum (ATM) has antioxidant and anti-adipogenic activity. However, few studies have investigated the pharmacological activity or mechanism of ATM as an antidepressant agent. We assessed the antidepressant effect of ATM in modulating menopausal depressive symptoms and its mechanisms in ovariectomized (OVX) and repeatedly stressed (RS) female rats. The female rats were randomly divided into four groups: (1) naïve normal (normal) group, (2) OVX + repeated stress + saline-treated (control) group, (3) OVX + repeated stress + ATM (100 mg•kg−1)-treated (ATM100) group and (4) OVX + repeated stress + ATM (400 mg•kg−1)-treated (ATM400) group. We performed a battery of tests, such as the forced swimming test (FST), the sucrose intake test, and social exploration. After behavior testing, serum corticosterone levels were examined, followed by immunohistochemical determination of c-Fos, tyrosine hydroxylase (TH), and interleukin-1 beta (IL-1β) expression in the brain. ATM administration was associated with significantly decreased immobility time in the FST. Also, the control group tended to have decreased sucrose intake and social exploration compared with the normal group. However, ATM treatment was associated with markedly increased sucrose intake and active social exploration. In the paraventricular nucleus, c-Fos and IL-1β expression were significantly decreased in the ATM400 group compared with the control group. Compared with the control group, high-dose ATM administration was also associated with markedly decreased expression of TH-immunoreactive neurons in the locus coeruleus. The study findings demonstrated that ATM treatment effectively decreased behavioral and pathophysiological depression-like responses.

Acer tegmentosum, a deciduous tree belonging to Aceraceae, has been used in traditional oriental medicine for treating hepatic disorders, such as hepatitis, cirrhosis, and liver cancer. We evaluated the estrogen-like effects of A. tegmentosum using an estrogen receptor (ER)-positive breast cancer cell line, namely MCF-7, to identify potential phytoestrogens and found that an aqueous extract of A. tegmentosum promoted cell proliferation in MCF-7 cells. Five phenolic compounds (1–5) were separated and identified from the active fraction using bioassay-guided fractionation of crude A. tegmentosum extract and phytochemical analysis. The chemical structures of the compounds were characterized as vanillic acid (1), 4-hydroxy-benzoic acid (2), syringic acid (3), isoscopoletin (4), and (E)-ferulic acid (5) based on the analysis of their nuclear magnetic resonance spectra and liquid chromatography-mass spectrometry data. All five compounds were evaluated using an E-screen assay for their estrogen-like effects on MCF-7 cells. Among the tested compounds, only 4-hydroxy-benzoic acid (2) promoted the proliferation of MCF-7 cells, which was mitigated by the ER antagonist, ICI 182,780. The mechanism underlying the estrogen-like effect of 4-hydroxy-benzoic acid (2) was evaluated via western blotting analysis to determine the expression levels of extracellular signal-regulated kinase (ERK), phosphoinositide 3-kinase (PI3K), serine/threonine kinase (AKT), and ERα. Our results demonstrated that 4-hydroxy-benzoic acid (2) induced the increase in the protein expression levels of p-ERK, p-AKT, p-PI3K, and p-Erα, concentration dependently. Collectively, these experimental results suggest that 4-hydroxy-benzoic acid (2) is responsible for the estrogen-like effects of A. tegmentosum and may potentially aid in the control of estrogenic effects during menopause.

Acer tegmentosum Maxim., commonly known as Manchurian stripe maple, is a deciduous tree belonging to the family of Aceraceae and has been traditionally used in folk medicine for its remedial effects in liver diseases and traumatic bleedings. With a growing body of experimental evidence for its pharmacological efficacies, such as neuroprotective, hepatoprotective, antioxidant, and anti-inflammatory activities, A. tegmentosum has gradually gained popularity as a health supplement and functional food. However, the large part of essential toxicity information still remained lacking despite the possibility of mutagenic potentials as previously suggested, posing safety concerns for human consumption. In this study, we evaluated 90-day repeated oral toxicity of A. tegmentosum Maxim. water extract (ATWE) in SD rats with acute toxicity assessment in beagle dogs, and reevaluated genotoxicity using a combination of in vitro and in vivo assays. During the oral study period, ATWE did not cause toxicity-related clinical signs and mortality in rodents without adverse effects observed in the analysis of hematology, serum biochemistry, and histopathology, establishing >5,000 mg/kg BW as the NOAEL. In addition, doses up to 5,000 mg/kg BW did not cause acute toxicity in beagle dogs. When assessed for genotoxicity using bacterial reverse mutation, chromosome aberration, and micronucleus formation, ATWE showed lack of mutagenicity and clastogenicity. These results demonstrated that AWTE was safe in the present preclinical study for systemic toxicity and genotoxicity at the tested doses, providing a guideline for safe use in humans.

In this research paper, work relating to microstrip monopole antenna is carried out. The objective is to aim for the ultra-wideband range which is 3.1 to 10.6 GHz. For this, a bio-inspired novel Korean striped maple leaf structure; under the binomial name, Acer Tegmentosum is considered. The design is carried out on a ground plane with dimensions 60 × 60 mm (W × L). The substrate used is FR4 epoxy with dielectric constant 4.4. The overall leaf dimension was taken to be 43.48 mm in terms of width with two adjacent petals of length 25.12 mm each and a center petal of length 16.42 mm. The maple leaf patch is supported by a partial ground of dimension 60 × 13.5 mm (W × L). Simulations were done and bandwidth achieved was 9.62 GHz (152.98%) from 1.47 GHz to 11.1 GHz with a peak gain of 6.53 dB. Comparisons are drawn for different antenna parameters. The proposed monopole structure is also fabricated and tested where a good agreement between simulated and measured results was seen.

Extraction from edible plants is a highly important process that has various biological functions. To maximize biological activity, extraction methods should facilitate optimal extraction of functional phytochemicals. In this study, the optimal hydrothermal extraction conditions of Acer tegmentosum were determined using response surface methodology (RSM), and HepG2 cells were treated with optimized extract and hydrogen peroxide. In a central composition design, the independent variables were extraction temperature (X1: 70&ndash, 90 &deg, C), extraction time (X2: 2&ndash, 6 h), and solvent-to-solid ratio (X3: 50&ndash, 150). The maximum total phenolic contents (276.70 &plusmn, 10.11 mg GAE/g) and DPPH (2,2-diphenyl-1-pictylhydrazyl) activity (33.45 &plusmn, 2.20%) of A. tegmentosum were estimated at optimized extraction conditions, as follows: X1: 89.34 &deg, C, X2: 7.36 h, X3: 184.09. Using the calculated extraction conditions, functional phytochemicals were extracted by hydrothermal extraction and freeze-dried. A. tegmentosum treatment (&gt, 10 &mu, g/mL) of HepG2 cells remarkably attenuated hydrogen-peroxide-inducible hepatic cellular death and reactive oxygen species production in vitro.

We investigated the effect of Acer tegmentosum Maxim (ATM) on adipocyte differentiation in 3T3-L1 cells and anti-obesity properties in obese rats fed a high-fat diet (HFD). Cellular lipid content in DMI (dexamethasone, 3&ndash, isobutyl&ndash, 1&ndash, methylxanthine, and insulin mixture)-treated cells increased, while ATM treatment caused a significant reduction in lipid accumulation in differentiated 3T3-L1 cells. ATM (60 ug/mL) caused inhibition of adipogenesis via down-regulation of the CCAAT/enhancer binding protein &beta, (C/EBP&beta, ) (48%), C/EBP&alpha, (66%), and peroxisome proliferator-activated receptor &gamma, (PPAR&gamma, ) (64%) expressions in 3T3-L1 cells. Moreover, ATM induced a decrease in the expressions of adipocyte-specific genes, such as adipocyte fatty acid-binding protein-2 (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL). Protein kinase B (Akt) and glycogen synthase kinase 3&beta, (GSK3&beta, ) phosphorylation was also decreased by ATM treatment of 3T3-L1 adipocytes. We investigated the anti-obesity effects of ATM on HFD-induced obese rats. Rats fed with an HFD demonstrated elevations in body weight gain, while the administration of ATM reversed body weight (BW) gains and adipose tissue weights in rats fed an HFD. ATM supplementation caused a decrease in the circulating triglyceride and total cholesterol levels and led to inhibition of lipid accumulation in the adipose tissues in HFD-induced obese rats. Epididymal fat exhibited significantly larger adipocytes in the HFD group than it did in the ATM-treated group. These results demonstrate that ATM administration caused a reduction in adiposity via attenuation in adipose tissue mass and adipocyte size.

Acer tegmentosum (ATM) has antioxidant and anti-adipogenic activity. However, few studies have investigated the pharmacological activity or mechanism of ATM as an antidepressant agent. We assessed the antidepressant effect of ATM in modulating menopausal depressive symptoms and its mechanisms in ovariectomized (OVX) and repeatedly stressed (RS) female rats. The female rats were randomly divided into four groups: (1) naïve normal (normal) group, (2) OVX + repeated stress + saline-treated (control) group, (3) OVX + repeated stress + ATM (100 mg•kg−1)-treated (ATM100) group and (4) OVX + repeated stress + ATM (400 mg•kg−1)-treated (ATM400) group. We performed a battery of tests, such as the forced swimming test (FST), the sucrose intake test, and social exploration. After behavior testing, serum corticosterone levels were examined, followed by immunohistochemical determination of c-Fos, tyrosine hydroxylase (TH), and interleukin-1 beta (IL-1β) expression in the brain. ATM administration was associated with significantly decreased immobility time in the FST. Also, the control group tended to have decreased sucrose intake and social exploration compared with the normal group. However, ATM treatment was associated with markedly increased sucrose intake and active social exploration. In the paraventricular nucleus, c-Fos and IL-1β expression were significantly decreased in the ATM400 group compared with the control group. Compared with the control group, high-dose ATM administration was also associated with markedly decreased expression of TH-immunoreactive neurons in the locus coeruleus. The study findings demonstrated that ATM treatment effectively decreased behavioral and pathophysiological depression-like responses.

The molecular phylogeny of Bacidia s.s. in the Russian Far East was investigated using 62 nucleotide sequences from the ITS nrDNA region, 22 of which were newly obtained. Phylogenetic reconstructions employed Bayesian inference and maximum likelihood searches using MrBayes and RAxML. In addition, ITS2 secondary structures added further support using Compensatory Base Changes. As a result of morphological and phylogenetic studies, four new species of Bacidia are described. Bacidia areolata sp. nov. belongs to the suffusa group. It was collected once in Khabarovskiy Krai, the Russian Far East, on the bark of Acer tegmentosum and is closely related to B. suffusa but differs in having a smooth, cracked to areolate thallus and shorter spores. Bacidia elongata sp. nov. is a member of the fraxinea group and is similar to B. fraxinea but differs in having a wide zone of cells with enlarged lumina along the edge of the exciple. In fact, this zone of enlarged cells, in combination with its overall habit, places it morphologically close to B. suffusa, B. millegrana and B. campalea. Bacidia kurilensis sp. nov. is a basal member of the laurocerasi group and closely related to B. biatorina, B. heterochroa, B. laurocerasi and B. salazarensis. However, the combination of a granular thallus, large black apothecia and a green hue in the upper part of the exciple edge as well as in the epihymenium sets it apart from the species mentioned above. Bacidia sachalinensis sp. nov. resolves as a strongly supported member of the polychroa group and is known from a single locality in Sakhalin, the Russian Far East. Its thallus structure and apothecium colour are variable, which is typical for the polychroa group, but it differs from B. polychroa by having shorter spores with fewer septa and a mainly smooth to areolate thallus.

A new flavonoid, 6-carboxyl-(−)-catechin methyl ester (1) was isolated from the stem bark of Acer tegmentosum, along with six known flavonoids (2–7). The structure of compound 1 was determined by spectral analyses, including HR-ESI-MS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. From present investigation, compound 7 was isolated for the first time from the Aceraceae family.

Background: The aim of this study was to investigate the effect of Acer tegmentosum Maxim (ATM) on adipocyte differentiation in 3T3-L1 adipocyte-derived cells and anti-obesity properties in high fat diet (HFD)-induced obese rats. Methods: 3T3-L1 adipocytes and HFD-induced obese rats were treated with ATM, and its effect on gene expression was analyzed using RT-PCR and Western blotting experiments. Results: Cellular lipid contents in DMI (dexamethasone, 3-isobutyl-1-methylxanthine, and insulin mixture)-treated cells increased, while ATM treatment caused a significant reduction in lipid accumulation in differentiated 3T3-L1 cells. ATM caused inhibition of adipogenesis via down-regulation of the CCAAT/enhancer binding protein β (C/EBPβ), C/EBPα, and peroxisome proliferator-activated receptor γ (PPARγ) expressions in 3T3-L1 cells. Moreover, treatment with ATM caused a decrease in the expressions of adipocyte-specific genes, such as adipocyte fatty acid-binding protein-2 (aP2), fatty acid synthase (FAS), and lipoprotein lipase (LPL), compared with DMI-stimulated adipocytes. In addition, phosphorylation levels of protein kinase B (Akt) and its downstream substrate, glycogen synthase kinase 3β (GSK3β), were significantly decreased by ATM treatment of 3T3-L1 adipocytes. Together, these results indicated that ATM caused inhibition of both adipocyte differentiation via suppression of the C/EBP family and PPARγ expressions and the Akt signaling pathway in 3T3-L1 adipocytes. In the present study, we further investigated anti-obesity effects of ATM on HFD-induced obese rats. Rats fed with HFD demonstrated elevations in body weight gain, while the administration of ATM significantly reversed BW gains and adipose tissue weights in rats fed HFD. ATM supplementation also caused a decrease in the circulating triglyceride levels and total cholesterol levels and led to inhibition of lipid accumulation in the adipose tissues in HFD-induced obesity in rats. Furthermore, epididymal fat exhibited larger adipocytes in the HFD group, whereas the ATM-treated group was significantly smaller than that of HFD group. These results strongly demonstrate that ATM administration caused a reduction in adiposity via attenuation in adipose tissue mass and adipocyte size. Conclusion: These finding demonstrated that ATM exerted anti-obesity effects through inhibition of adipocyte differentiation and adipogenesis, leading to a decrease in BW and fat tissue mass in HFD-induced obesity in rats.

We previously reported that Acer tegmentosum extract, which is traditionally used to treat liver disease in Korea, may help reduce fat accumulation, improve liver metabolism, and suppress inflammation in alcoholic liver disease. The active ingredient was found to be 6-O-galloylsalidroside, which was isolated from the methanol extract of A. tegmentosum. We hypothesized that 6-O-galloylsalidroside extracted from A. tegmentosum may help protect from liver damage and attenuate hepatic fat accumulation associated with chronic alcohol consumption. In the present study, we aimed to investigate whether 6-O-galloylsalidroside can regulate alcoholic fatty liver and liver injury in mice. For this purpose, mice were fed with Lieber-DeCarli 5% ethanol diet for 11 days to induce steatosis and liver injury. Oral 6-O-galloylsalidroside was administered once a day for 11 days. Intrahepatic lipid accumulation caused by alcohol consumption was measured using in vivo 1H magnetic resonance imaging. Hepatic steatosis was observed histologically in tissue samples stained with hematoxylin and eosin, as well as Oil Red O. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured, as well as the triglyceride content in liver homogenates. On magnetic resonance spectroscopy, 6-O-galloylsalidroside appeared to alleviate alcohol-induced steatosis, which was reflected in decreased hepatic and serum triglyceride levels despite ethanol feeding. Furthermore, 6-O-galloylsalidroside treatment was associated with decreased RNA expression of Cd36, which plays an important role in the development of alcoholic steatosis through the hepatic de novo lipogenesis pathway. Furthermore, treatment with 6-O-galloylsalidroside inhibited the expression of cytochrome P4502E1 and attenuated hepatocellular damage, reflected in reduced ALT and AST levels. These findings suggest that 6-O-galloylsalidroside extracted from A. tegmentosum might serve as a bioactive agent for treating alcoholic fatty liver and liver damage.

Objective Periodontitis disease is a chronic inflammation, and the prevention or treatment of periodontal disease is important for improving oral health and averting systemic diseases.Acer tegmentosum Maxim (ATM) is a type of deciduous tree in Korea. ATM extracts have been traditionally used to treat various dieases. This study investigated the effects of ATM extract on mitigation of periodontitis in vitro and in vivo. Design The current study investigated whether extracts ofAcer tegmentosum Maxim (ATM) attenuated periodontitis induced by Porphyromonas gingivalis-derived lipopolysaccharide (LPS) in vitro and in vivo. We used a rat model of experimental periodontitis that received oral administration of 1 mg/kg P. gingivalis-derived LPS for 10 days. Periodontitis models was treated with two different dosages of ATM (30 or 100 mg/kg) during the same period of periodontal induction for histological analysis. Results The results indicated that aqueous ATM extracts effectively ameliorated ligature-induced periodontitis through of the antibacterial, anti-oxidative, and anti-inflammatory activities. Conclusion These pre-clinical results suggest the need for further studies on the anti-periodontitis effect of ATM in humans. Thus, ATM could be used as a natural anti-periodontitis agent for the treatment of periodontitis.

A new phenolic glycoside, 4-hydroxyphenylethyl-1-O-β-D-[6′-O-(4-hydroxybenzoyl)]-glucopyranoside (1) was isolated from the stem bark of Acer tegmentosum, along with seven known phenolic compounds (2–8). The structure of compound 1 was determined by spectral analyses, including HR-ESI-MS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. Compounds 3 and 4 were found in the family Aceraceae for the first time.

Phytoestrogens derived from plants have attracted the attention of the general public and the medical community due to their potentially beneficial role in relieving menopausal symptoms. The deciduous tree Acer tegmentosum Maxim (Aceraceae) has long been utilized in Korean folk medicine to alleviate many physiological disorders, including abscesses, surgical bleeding, and liver diseases. In order to explore structurally and/or biologically new constituents from Korean medicinal plants, a comprehensive phytochemical study was carried out on the bark of A. tegmentosum. One new phenolic compound with a 1,4-benzodioxane scaffold, isoamericanoic acid B (1), as well as with nine known phenolic compounds (2⁻10), were successfully isolated from the aqueous extracts of the bark of A. tegmentosum. A detailed analysis using 1D and 2D NMR spectroscopy, electronic circular dichroism (ECD) spectral data, and LC/MS afforded the unambiguous structural determination of all isolated compounds, including the new compound 1. In addition, compounds 2, 4, 5, and 9 were isolated and identified from the bark of A. tegmentosum for the first time. All isolated compounds were tested for their estrogenic activities using an MCF-7 BUS cell proliferation assay, which revealed that compounds 1, 2, and 10 showed moderate estrogenic activity. To study the mechanism of this estrogenic effect, a docking simulation of compound 1, which showed the best estrogenic activity, was conducted with estrogen receptor (ER) -α and ER-β, which revealed that it interacts with the key residues of ER-α and ER-β. In addition, compound 1 had slightly higher affinity for ER-β than ER-α in the calculated Gibbs free energy for 1:ER-α and 1:ER-β. Thus, the present experimental evidence demonstrated that active compound 1 from A. tegmentosum could be a promising phytoestrogen for the development of natural estrogen supplements.

Phytoestrogens derived from plants have attracted the attention of the general public and the medical community due to their potentially beneficial role in relieving menopausal symptoms. The deciduous tree Acer tegmentosum Maxim (Aceraceae) has long been utilized in Korean folk medicine to alleviate many physiological disorders, including abscesses, surgical bleeding, and liver diseases. In order to explore structurally and/or biologically new constituents from Korean medicinal plants, a comprehensive phytochemical study was carried out on the bark of A. tegmentosum. One new phenolic compound with a 1,4-benzodioxane scaffold, isoamericanoic acid B (1), as well as with nine known phenolic compounds (2–10), were successfully isolated from the aqueous extracts of the bark of A. tegmentosum. A detailed analysis using 1D and 2D NMR spectroscopy, electronic circular dichroism (ECD) spectral data, and LC/MS afforded the unambiguous structural determination of all isolated compounds, including the new compound 1. In addition, compounds 2, 4, 5, and 9 were isolated and identified from the bark of A. tegmentosum for the first time. All isolated compounds were tested for their estrogenic activities using an MCF-7 BUS cell proliferation assay, which revealed that compounds 1, 2, and 10 showed moderate estrogenic activity. To study the mechanism of this estrogenic effect, a docking simulation of compound 1, which showed the best estrogenic activity, was conducted with estrogen receptor (ER) -α and ER-β, which revealed that it interacts with the key residues of ER-α and ER-β. In addition, compound 1 had slightly higher affinity for ER-β than ER-α in the calculated Gibbs free energy for 1:ER-α and 1:ER-β. Thus, the present experimental evidence demonstrated that active compound 1 from A. tegmentosum could be a promising phytoestrogen for the development of natural estrogen supplements.

Ethnopharmacological relevance Acer tegmentosum Maxim (AT), the East Asian stripe maple, is an herb used to treat liver disease and is approved as a functional food in Korea. AT protects against hepatic disorders, atopic dermatitis, and diabetes mellitus. Aim of the study We explored the mechanism of the hepatoprotective effects of AT extract in in vitro and in vivo levels. Materials and methods AT extract from Acer tegmentosum Maxim was extracted by hot water. Hepatoprotective effects of AT extract were confirmed using carbon tetrachloride (CCl4)- or alcohol-induced mouse model, and H2O2- or alcohol-induced HepG2 (liver hepatocellular carcinoma cell line) cells by measuring GOT, GPT, TG, and MDA levels. Hematoxylin and eosin (H&E) staining was used to observe the pathological analysis. Cytotoxicity or protective effect of AT extract was confirmed using MTT assay in HepG2 cells. Antioxidant effect of AT extract was measured using DPPH or H2DCFDA assay. Mechanism study of antioxidant and autophagy was carried out using western blotting and immunofluorescence analysis. Results AT extract increased the viability of HepG2 cells treated with H2O2 and ethanol, and protected the liver against damage induced by CCl4 and alcohol. The AT extract increased the levels of nuclear respiratory factor 2 (Nrf2) and heme oxygenase-1 (HO-1). The level of microtubule-associated protein light chain 3 (LC3)-Ⅱ, beclin-1, autophagy-related genes (Atg) such as Atg3 and Atg12-5 as markers of autophagy activation was also increased. Moreover, the AT extract increased activation of mitogen-activated protein kinase (MAPK), which regulated autophagy and HO-1. Conclusion Therefore, these results indicate that the AT extract has a hepatoprotective effect by increasing antioxidant activity and inducing autophagy.

The aim of the present study was to sequence and analyze the complete plastid genome (i.e. plastome) of Acer tegmentosum Maxim. The plastome of A. tegmentosum was 156,435 bp in length and included both large (86,265 bp) and small (18,102 bp) single-copy regions, which were separated by a pair of identical inverted repeats (26,034 bp). The plastome contained 77 unique protein-coding genes, 30 tRNA genes, and four rRNA genes. In addition, the gene order and organization of the A. tegmentosum plastome were consistent with those of plastomes from other members of the Sapindaceae, and the overall GC content of the plastome was 37.8%. A phylogenetic tree that was based on 76 protein-coding genes demonstrated a sister relationship within genus Acer.

Ethnopharmacological relevance Atopic dermatitis (AD) is a chronic and relapsing inflammatory condition characterized by pruritic and eczematous skin lesions that requires safe and effective pharmacological therapy. The bark of Acer tegmentosum Maxim trees has been used in Korean folk and traditional medicine to treat abscesses, surgical bleeding, liver diseases, and AD. Aim of study To investigate the therapeutic effect of A. tegmentosum , on a mouse model of Dermatophagoides farinae (Df)-induced AD. Methods Development of AD-like skin lesions was induced by repetitive skin contact with barrier-disrupted backs of NC/Nga mice with Df body ointment, and the effects of A. tegmentosum were evaluated on the basis of histopathological skin assessment results, ear swelling, and cytokine production in the dorsal skin. The component of A. tegmentosum , salidroside, inhibited the production of TSLP in KCMH-1 cells, which indicated that its production could be pharmacologically regulated. Results Topical application of A. tegmentosum for 1 week after Df body ointment challenge significantly reduced ear swelling and improved dorsal skin lesions. Suppression of dermatitis by combined therapy was accompanied by a decrease in the skin level of Th2 cytokines, such as interleukin (IL)-4, IL-5 and IL-13, plasma levels of thymus and activation-regulated chemokine, and IgE. Induction of thymic stromal lymphopoietin, which leads to a systemic Th2 response, was also reduced in in vivo and in vitro by A. tegmentosum and salidroside. Conclusions Our findings suggest that A. tegmentosum treatment has a significant therapeutic effect on Df-induced AD-like skin lesions on NC/Nga mice through inhibition of thymic stromal lymphopoietin and IgE via a mechanism that may inhibit Th2-mediated immune responses. These results suggest that A. tegmentosum and salidroside may be useful tools for the treatment of AD.

The objective of this study was to investigate anticytotoxic and antioxidatative capacities of ethanol extracts from Acer tegmentosum Maxim (A. tegmentosum) stem in vitro. The extract at concentration of 200 ug/mL inhibited 10 and 20 ug/mL arsenic trioxide-induced cytotoxicity of HepG2 cells by 79.3 and 57.5%, respectively. The extract at concentration of 200 ug/mL inhibited 0.2 and 0.5 mM t-BHP-induced cytotoxicity of HepG2 cells by 66.3 and 35.7%, respectively. Antioxidative effects of the extract were examined via measurement of ABTS, superoxide, and peroxyl radical scavenging activities. ABTS radical scavenging activity of the extract was higher than that of -tocopherol. Superoxide scavenging activity of the extract was higher than that of catechin. Oxygen radical absorbance capacity of the extract was higher than that of ascorbic acid. Cupric reducing antioxidant capacity of the extract was higher than that of -tocopherol. The extract at concentrations of 100 and inhibited 10 mM t-BHP-induced lipid peroxidation of HepG2 cells by 38.2 and 80.7%, respectively. The extract prevented supercoiled DNA strand breakage induced by hydroxyl or peroxyl radical. Total phenolic and flavonoid contents of the extract at concentration of were 71.3 nmol/mL gallic acid and 18.8 nmol/mL catechin equivalents, respectively. Thus, strong cytoprotective and antioxidant effects of A. tegmentosum stem extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in polyphenolic contents.

Acer tegmentosum Maxim (AT) is a species of the maple genus, which is native to North-Eastern China and Korea. Traditionally, AT has been already used for pain relief in Korea. On the other hand, its antidepressant-like activity and related molecular mechanisms is not completely understood. Using the Forced Swimming Test (FST), the effects of a subacute treatment with AT(100, 200, and 400 mg/kg, p.o.) on the immobility and FST-induced changes to the immune parameters, cortisol, ACTH, and cytokine, in rats were investigated. The tendency of immobility showed a dose-dependent decrease in FST. The levels of cortisol, IL-6 and IL-1β in the peripheral blood were increased significantly after FST exposure. Overall, these results suggest that AT treatment can decrease the immobility time and the release of pro-inflammatory cytokines in the FST, suggesting that the anti-inflammatory effects of AT might be involved in the antidepressant-like effect.

In this study, we investigated the anticancer activity of a newly isolated compound from Acer tegmentosum Maxim (ATM) in HepG2 cells. This compound was isolated by reverse-phase high-performance liquid chromatography (RP-HPLC) in a butanol-soluble fraction, which was shown to have the strongest anticancer activity. The isolated compound was identified as salidroside using multiple nuclear magnetic resonance (NMR) techniques, including 1H, 13C, correlated spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), and heteronuclear multiple bond correlation (HMBC), as well as electrospray ionization mass spectroscopy (ESI/MS). The activity of salidroside was evaluated in HepG2 cells by analyzing cell proliferation, cell cycle distribution, Hoechst 33342 staining, and Western blots of apoptotic regulatory proteins. The results show that salidroside, an anticancer compound from ATM, exhibits strong apoptotic activity in HepG2 cells. Therefore, ATM extracts could be used as chemotherapeutic agent to induce apoptosis in hepatoblastoma cells.

Acer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n-BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as on-line screening HPLCABTS+ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase fromAcer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n- BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as online screening HPLC-ABTS+ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase from 3 kg of dry biomass. The on-line screening HPLC-ABTS+ assay is rapid and efficient tool to search bioactivity from A. tegmentosum. 3 kg of dry biomass. The on-line screening HPLC-ABTS+ assay is rapid and efficient tool to search bioactivity from A. tegmentosum.

In our ongoing research to discover natural products with neuroprotective effects, hyperoside (quercetin 3-O-galactoside) was isolated from Acer tegmentosum, which has been used in Korean traditional medicine to treat liver-related disorders. Here, we demonstrated that hyperoside protects cultured dopaminergic neurons from death via reactive oxygen species (ROS)-dependent mechanisms, although other relevant mechanisms of hyperoside activity remain largely uncharacterized. For the first time, we investigated the neuroprotective effects of hyperoside on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in neurons, and the possible underlying mechanisms. Hyperoside significantly ameliorated the loss of neuronal cell viability, lactate dehydrogenase release, excessive ROS accumulation and mitochondrial membrane potential dysfunction associated with 6-OHDA-induced neurotoxicity. Furthermore, hyperoside treatment activated the nuclear erythroid 2-related factor 2 (Nrf2), an upstream molecule of heme oxygenase-1 (HO-1). Hyperoside also induced the expression of HO-1, an antioxidant response gene. Remarkably, we found that the neuroprotective effects of hyperoside were weakened by an Nrf2 small interfering RNA, which blocked the ability of hyperoside to inhibit neuronal death, indicating the vital role of HO-1. Overall, we show that hyperoside, via the induction of Nrf2-dependent HO-1 activation, suppresses neuronal death caused by 6-OHDA-induced oxidative stress. Moreover, Nrf2-dependent HO-1 signaling activation represents a potential preventive and therapeutic target in Parkinson&prime, s disease management.

The purpose of this study is to evaluate the antioxidant activities of extracts from Acer tegmentosum Maxim. (AT) and the ability of these extracts to reduce the serum alcohol concentration in rats administered alcohol. The total amount of polyphenols in hot water and ethanol extracts from AT were 71.93±2.2 μg/mg and 152.69 ±1.25 μg/mg, respectively, while the total amount of flavonoids in hot water and ethanol extracts from AT were 7.51±1.34 μg/mg and 5.01±0.83 μg/mg, respectively. FRAP values in AT extracts were 1.67～1.75 μM/μg. AT extracts were capable of directly scavenging DPPH and ABTS free radicals, with higher inhibitory activities for TBA. The hepatoprotective effect of hot water extracts from AT against ethanol-induced oxidative damage was investigated. Ethanol-induced damage on HepG2 liver cells were protected by hot water extracts from AT. Administration of hot water extracts from AT (200 mg/kg) had reduced serum alcohol levels in acute alcohol-treated rats. These results indicate that AT extracts can be protective against alcohol-induced toxicity, potentially through its antioxidant properties.

This study was carried out to investigated optimum mixing ratio of Korean natural Acer tegmentosum for production of functional oyster mushroom. Total nitrogen and carbon sources of Acer tegmentosum were 0.2% and 44.4%, respectively and C/N ratio was 234. Total nitrogen source and pH of substrate mixed with Acer tegmentosum were 2.7~2.9 and 4.8~5.0, respectively. The contents of , and MgO at Acer tegmentosum media were higher than that of the control. Mycerial growth was the fastest at Acer tegmentosum 10%, and slower by increase of Acer tegmentosum substrate. Yields of fruiting body was the highest to 159 g/850 mL at 10% of Acer tegmentosum and dimeter and thick of pileus were the highest, too. The L value of pileus and stipes were decreased by increase of Acer tegmentosum substrate, but there was no significant difference in the a-value and the b-value. The contents of and of fruiting body were increased at Acer tegmentosum substrate, but there was no significant difference in contents of CaO, MgO and .

This study evaluates stoichiometry patterns in the androdioecious Acer tegmentosum, a species characterized by a rare reproductive system where males and hermaphrodites coexist. Altogether 31 hermaphrodites and 29 male plants were harvested and samples of leaves, current-year shoots, branches and coarse roots were analyzed to explore gender differences in biomass, C, N and P concentrations of these four components. The nitrogen to phosphorus relationship of each component was examined using SMA estimates. Males had significantly greater amounts of leaf and coarse root dry matter content than hermaphrodites. C, N and P stoichiometry differed significantly between genders, especially in the newly emerging vegetative components (leaves and shoots). Males had higher C/N and C/P ratios in current-year shoots and lower C/P ratios in leaves and branches. Hermaphrodites had higher N/P ratios in the leaves and branches. Males had higher rates of increase in leaf P content than hermaphrodites. This study suggests that stoichiometry patterns may be significantly affected by gender.

This study was performed to investigate the preventing effects to liver injury of Acer tegmentosum Maxim. extract (ATE). After oral administration ATE to SD rats, liver injuries were induced by CCl4, galactosamine or ethionine treatments. The aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride and cholesterols in blood were used as indicators of liver damage. When acute hepatitis was induced by CCl4 or galactosamine, ATE-fed rats showed low level of AST and ALT in plasma than the ATE-unfed rats. In case of ethionine-induced fatty liver, the triglyceride in plasma were shown to reduced level in ATE-fed rats than ATE-unfed rats. These results indicate that Acer tegmentosum Maxim. extract protected hepatic failure.

The objective of this study was to investigate the anticancer effects of Acer tegmentosum M. extracts. HepG2 hepatocarcinoma cells were treated with ethanol, chloroform, ethylacetate, butanol, aqueous fraction and hot water extract. The antiproliferative effect was evaluated by trypan blue exclusion, MTT-based viability assay and morphology. The trypan blue test showed that anticancer effect of the A. tegmentosum M. extracts on HepG2 cells increased gradually in proportion to the increasing concentration of the fractions. The butanol fraction showed the highest anticancer activity against HepG2 cells (p

While Acer tegmentosum M. (AT) has been widely used as a popular folk remedy to prevent or treat liver diseases in Korea, the scientific evidences for the usage of AT against liver disease are poorly documented. To address this issue, we compared hepatoprotection of hot water extract (WEAT) from three parts of AT, boughs (E1), twigs (E2), and leaves (E3), on CCl4-induced acute hepatic injury in mice by way of morphometric and biochemical examination: liver function test, antioxidant enzymes activity of liver, histopathological and ultrastructural examination of liver, and antioxidant capacity (DPPH assay) of WEAT. We found that only oral intake group of WEAT-boughs showed significant differences in aspartate transaminase (AST), alanine transaminase (ALT) levels and glutathione peroxidase (GPx) activities as compared to CCl4 control group, whereas the glutathione levels were significantly low in all WEAT-pretreated groups. Consistently, histopathological and ultrastructural findings displayed hepatoprotection in the order of WEAT-boughs >WEAT-twigs>WEAT-leaves. Collectively, these results indicate that of three WEAT, WEAT-bough extract has the highest hepatoprotection against CCl4-induced acute hepatic injury in mice via the possible regulation of antioxidant enzyme activities in liver.

현재까지 산겨릅나무의 식물화학적인 연구는 수피부에 국한되어 있으며, 목질부의 성분연구는 전혀 보고된 것이 없다. 본 연구는 산겨릅나무 목질부로부터 2개의 flavan 3-ol, 3개의 phenolic acid/alcohol 및 2개의 coumarin 화합물을 컬럼크로마토그래피를 연속적으로 실시하여 분리하였다. 화합물의 구조는 $^1H$ -NMR, $^{13}C$ -NMR, 2D-NMR 및 MS 스펙트럼을 분석하여, (+)-catechin (1), (-)-epicatechin (2), $p$ -hydroxybenzaldehyde (3), syringic alcohol (4), $p$ -tyrosol (5), scopoletin (6) 및 cleomiscosin A (7)으로 동정하였으며, 그 중 $p$ -hydroxybenzaldehyde (3), syringic alcohol (4), scopoletin (6) 및 cleomiscosin A (7)는 산겨릅나무에서는 처음 분리하였다. 화합물의 DPPH 라디칼 소거활성 측정 결과 (+)-catechin (1)과 (-)-epicatechin (2)은 양성 대조구로 사용한 BHA보다 우수한 항산화 활성을 나타냈다. 【There have been few reports on the constituents and biological activity of stem bark of $Acer$ $tegmentosum$ , and no phytochemical and biological studies have been reported for stem wood of $A.$ $tegmentosum$ . Two flavan 3-ols (1 and 2), three phenolic acid/alcohols (3~5), and two coumarins (6 and 7) were isolated from the stem wood of $A.$ $tegmentosum$ by repeated column chromatography. The structure of isolated compounds were identified as (+)-catechin (1), (-)-epicatechin (2), $p$ -hydroxybenzaldehyde (3), syringic alcohol (4), $p$ -tyrosol (5), scopoletin (6), and cleomiscosin A (7) on the basis of spectroscopic evidences such as $^1H$ -NMR, $^{13}C$ -NMR, 2D-NMR and MS spectrum. $p$ -Hydroxybenzaldehyde (3), syringic alcohol (4), scopoletin (6), and cleomiscosin A (7) have not been reported from this plant so far. (+)-Catechin (1) and (-)-epicatechin (2) showed the higher 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than butylated hydroxyanisole (BHA) used as a positive control.】

Aim of study Acer tegmentosum has been traditionally used for folk medicine to treat hepatic disorders such as hepatitis, hepatic cancer, and hepatic cirrhosis. In this study, we demonstrate the ethno-pharmacological activity of Acer tegmentosum in in vitro and in vivo inflammatory conditions. Results The 70% ethanol extract (At-EE) of Acer tegmentosum dose-dependently diminished the production of nitric oxide (NO), tumour necrosis factor (TNF)-α, and prostaglandin (PG)E2, in lipopolysaccharide (LPS)-activated RAW264.7 cells and peritoneal macrophages, by a transcriptional mechanism. At-EE also suppressed the activation of nuclear factor (NF)-κB, activator protein (AP)-1, and cAMP-responsive element binding (CREB), and simultaneously blocked their upstream inflammatory signalling cascades, including Akt, p38, and JNK. Furthermore, At-EE protected against LPS-induced cell death induced by reactive oxygen species (ROS) and reactive nitrogen species (RNS) and neutralized reactive species generation. In agreement with the in vitro results, orally administered At-EE strongly ameliorated ear oedema formation induced by arachidonic acid. Conclusion At-EE displays strong anti-inflammatory activities in vitro and in vivo, contributing to its major ethno-pharmacological role such as anti-hepatitis remedy and may be applicable to novel anti-inflammatory therapeutics.

The heartwood of Acer tegmentosum(Acereaceae) has been used as a Korean traditional medicinal drug against alcohol poisoning and hepatitis. To find the biologically active substance in A. tegmentosum heartwood, we investigated the protective effects of the heartwood extract and its constituents on pain and gastropathy in mouse. In these experiments, salidroside, a major compound, significantly reduced gastric lesion and pain in mice. Oral administration of salidroside at the 10 and 20 mg/kg doses greatly reduced the gastric lesion induced by HCl/ethanol (inhibitory effect, 51.5 and 68.8%, respectively) and by indomethacin/bethanechol (inhibitory effect, 31.3 and 38.8%, respectively). Salidroside also stabilized pH of gastric juice and the increase of gastric juice secretion and total acid output. Taken together, these results demonstrated that salidroside is the main ingredient of A. tegmentosum heartwood to prevent gastric lesion and pain that can be caused by drinking alcohol.

This study was carried out to investigate antioxidative and hepatoprotective effects of Acer tegmentosum M. (ATM) extracts. Content of total polyphenol of EtOAc fraction was the highest amount among fractions. Electron donating abilities of all fractions were increased as concentrations of each fraction were increased. ATM BuOH fraction showed the highest SOD like activity at low concentration (＜250 ㎍/mL). To investigate the protective effect of ATM on hepatotoxicity, ATM BuOH fraction was administered to mice for 7 consecutive days, and then lipopolysaccharide (LPS) was injected at a dosage of 1 mg/kg. The LPS led to increase of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and blood urea nitrogen (BUN). However, pretreatment with BuOH fraction prior to LPS injection significantly decreased plasma hepatospecific enzyme levels. Histological findings demonstrated that pretreatment with BuOH fraction resulted in an attenuation of LPS induced liver damages.

Acer tegmentosum is a type of deciduous tree that grows in Korea. It has been used in traditional medicine for the treatment of hepatic disorders. In this study, chromatography fractionation and isolation have been successfully used to yield 15 compounds, including 10 flavonoids, 4 phenylethyl glycosides, and 1 other glycoside. Their structures were determined on the basis of their physical and spectral properties [(1)H and (13)C nuclear magnetic resonance (NMR) and mass spectrometry (MS)] and by comparison of these results to similar data in the literature. The total peroxyl radical-scavenging capacity of each isolated compound was evaluated. Among them, the most active components belong to the flavonoids. Among these, quercitrin (1), 6-hydroxy-quercetin-3-O-galactose (6), and (+)-catechin (8) showed stronger activity than the positive control Trolox.

Yamatochaitophorus yichunensis sp. n. is described from specimens collected in northeast China on Acer tegmentosum (Aceraceae). Yamatochaitophorus is also a new generic record for China. Type specimens are deposited in the National Zoological Museum of China, Institute of Zoology, Chinese Academy of Sciences, Beijing, China (NZMC) and the Natural History Museum, London, UK (BMNH).

International audience; AbstractKey messageWe present comparisons about biomass allocation between males and hermaphrodites of androdioeciousAcer tegmentosumMaxim.. Different biomass allocation patterns were found, and males were shown to have a larger investment into coarse roots and foliage.ContextSexual dimorphism in differences of reproductive costs between genders has been widely reported for trees, but we still know little about allometric relationships between tree components in both genders.AimsWe present biomass allocation patterns and relationships between components of the androdioecious A. tegmentosum in a broad-leaved mixed forest in northeastern China. The objectives of this study were to examine how gender affects the biomass structure of androdioecious species and how the gender-related reproductive efforts affect the allometric relationships.MethodsWe harvested 31 hermaphrodite and 29 male A. tegmentosum trees and opted for diameter at breast height, tree height, and crown length as the independent variables and various biomass components as the dependent variables. Five types of function were used to model allometry equations.ResultsBiomass allocation between genders was different, and the best biomass model for each biomass component varies between genders. Males have a higher investment in foliage and coarse root biomass than hermaphrodites, and hermaphrodites invested more in reproduction than males.ConclusionBiomass equations are strongly gender-related. Males tended to invest a larger fraction of the vegetative biomass into leaves and coarse roots.

This study was designed to examine effects of Korean Acer tegmentosum Maximowocz extract, which has traditionally been used for the treatment of liver damages in fat diet-induced obese rats. 40 male SD rats were divided into three groups: normal diet (Control group, n=10), 40% fat diet- induced obese rats (Obesity group, n=15), and Acer tegmentosum Maximowoczextract diet with 40% fat diet-induced obese rats (ATM group, n=15). Hematological and biochemical variables were measured. Histological examinations of liver and adipose tissues were performed with hematoxylin & eosin stain. Total leukocyte, neutrophil, neutrophil/lymphocyte ratio, erythrocyte, platelet, hemoglobin, and red distribution width levels were significantly higher, whereas monocyte levels were lower in obesity group than in control and ATM group. Glucose, total cholesterol, triglyceride, LDL- cholesterol, AST, ALT, and BUN levels in obesity group were significantly greater than those of ATM. ATM group showed significantly lower liver fatty degeneration (steatosis) than obesity group. These results suggest that Korean Acer tegmentosum Maximowocz exerts anti-inflammatory and anti-obesity effects.

Methanol extracts of domestic plants of Korea were evaluated as a potential inhibitor of neutral pH optimum and membrane-associated 60 kDa sphingomyelinase (N-SMase) activity. In this study, we partially purified N-SMase from bovine brain membranes using ammonium sulfate. It was purified approximately 163-fold by the sequential use of DE52, Butyl-Toyopearl, DEAE-Cellulose, and Phenyl-5PW column chromatographies. The purified N-SMase activity was assayed in the presence of the plant extracts of three hundreds species. Based on the in vitro assay, three plant extracts significantly inhibited the N-SMase activity in a time- and concentration-dependent manner. To further examine the inhibitory pattern, a Dixon plot was constructed for each of the plant extracts. The extracts of Abies nephrolepis, Acer tegmentosum, and Ginkgo biloba revealed a competitive inhibition with the inhibition constant (Ki) of 11.9 microg/ mL, 9.4 microg/mL, and 12.9 microg/mL, respectively. These extracts also inhibited in a dose-dependent manner the production of ceramide induced by serum deprivation in human neuroblastoma cell line SH-SY5Y.

In this paper, the methods such as Clumping index, Aggregate index, CASSIE index, Diffusion coefficient C, K index in negative binomial distribution and m*-m wao regression, Taylor power law were used to analyze the spatial distribution pattern of Thuja koraiensis community. The results showed that the spatial distribution pattern of Thuja koraiensis community presented significantly aggregate distribution. Based on 2×2 contingency table, interspecific association analysis was conducted by means of Variance ratio method, χ2-test, Association coefficient, together with point correlation coefficient, The overall relevance of pure forest community where Thuja koraiensis population were distributed and scattered forest of Thuja koraiensis community both showed negative correlation. In the pure forest community, Thuja koraiensis was extremely significantly negatively correlated with Sorbus pohuashanensis(pThuja koraiensis was positively correlated with Euonymus rehderianus, Lonicera edulis, Rubus sachalinensis, Acer tegmentosum, and negatively correlated with other species. Studies suggest that protecting species which are positively correlated with Thuja koraiensis to form an environment conducive to the survival of specific species together has certain guiding significance for the protection and utilization of Thuja koraiensis community.

Chronic alcohol consumption causes alcohol-induced lipogenesis and promotes hepatic injury by preventing the oxidation of hepatocellular fatty acids through the suppression of the activation of AMP-activated protein kinase (AMPK). HIMH0021, an active flavonoid compound, which is a component of the Acer tegmentosum extract, has been shown to protect against liver damage caused by alcohol consumption. Therefore, in this study, we aimed to determine whether HIMH0021 could regulate alcoholic fatty liver and liver injury in mice. Oral administration of 10 days of Lieber-DeCarli ethanol plus a single binge of 30% ethanol (chronic-plus-binge model) induced steatosis and liver injury and inflammation in mice, which appears similar to the condition observed in human patients with alcohol-related diseases. HIMH0021, which was isolated from the active methanol extract of A. tegmentosum, inhibited alcohol-induced steatosis and attenuated the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) during hepatocellular alcohol metabolism, both of which promote lipogenesis as well as liver inflammation. Treatment with HIMH0021 conferred protection against lipogenesis and liver injury, inhibited the expression of cytochrome P4502E1, and increased serum adiponectin levels in the mice subjected to chronic-plus-binge feeding. Furthermore, in hepatocytes, HIMH0021 activated fatty acid oxidation by activating pAMPK, which comprises pACC and CPT1a. These findings suggested that HIMH0021 could be used to target a TNFα-related pathway for treating patients with alcoholic hepatitis.

Fraxin isolated from Acer tegmentosum is reported to exert potent anti-oxidative stress action. However, pharmacological activities of fraxin remain to be elucidated. This study investigated the potential hepatoprotective effects of fraxin and the underlying signaling mechanism involved. Treatment with fraxin significantly lowered the serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in a CCl4-induced hepatotoxicity rat model. In the fraxin-treated group, glutathione (GSH) significantly increased, while the malondialdehyde (MDA) in the liver significantly decreased. Fraxin also showed radical-scavenging activity. Furthermore, it significantly reduced the t-BHP-induced cytotoxicity and production of reactive oxygen species (ROS) in Hep G2. Fraxin protected Hep G2 cells through Nrf2 pathway-dependent HO-1 expression. The results of this study indicate that fraxin shows potent hepatoprotective effects in vitro and in vivo, presumably through direct antioxidant activity and the Nrf2-mediated antioxidant enzyme system.

The stem of Acer tegmentosum has been widely used in Korea for the treatment of hepatic disorders. In this study, we investigated the bone protective effect of water extract of the stem of Acer tegmentosum (WEAT). We found that WEAT inhibits osteoclast differentiation induced by receptor activator of nuclear factor-κB ligand (RANKL), an essential cytokine for osteoclast differentiation. In osteoclast precursor cells, WEAT inhibited RANKL-induced activation of JNK, NF-κB, and cAMP response element-binding protein, leading to suppression of the induction of c-Fos and nuclear factor of activated T cells cytoplasmic 1, key transcription factors for osteoclast differentiation. In addition, WEAT inhibited bone resorbing activity of mature osteoclasts. Furthermore, the oral administration of WEAT reduced RANKL-induced bone resorption and trabecular bone loss in mice. Taken together, our study demonstrates that WEAT possesses a protective effect on bone destruction by inhibiting osteoclast differentiation and function.