Anti-hyperuricemia effect of hesperetin is mediated by inhibiting the activity of xanthine oxidase and promoting excretion of uric acid.

Hesperetin is a natural flavonoid with many biological activities. In view of hyperuricemia treatment, the effects of hesperetin in vivo and in vitro, and the underlying mechanisms, were explored. Hyperuricemia models induced by yeast extract (YE) or potassium oxonate (PO) in mice were created, as were models based on hypoxanthine and xanthine oxidase (XOD) in L-O2 cells and sodium urate in HEK293T cells. Serum level of uric acid (UA), creatinine (CRE), and urea nitrogen (BUN) were reduced significantly after hesperetin treatment in vivo. Hesperetin provided hepatoprotective effects and inhibited xanthine oxidase activity markedly, altered the level of malondialdehyde (MDA), glutathione peroxidase (GSH-PX) and catalase (CAT), downregulated the XOD protein expression, toll-like receptor (TLR)4, nucleotide binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, interleukin-18 (IL-18), upregulated forkhead box O3a (FOXO3a), manganese superoxide dismutase (MnSOD) in a uric acid-synthesis model in mice. Protein expression of organic anion transporter 1 (OAT1), OAT3, organic cationic transporter 1 (OCT1), and OCT2 was upregulated by hesperetin intervention in a uric acid excretion model in mice. Our results proposal that hesperetin exerts a uric acid-lowering effect through inhibiting xanthine oxidase activity and protein expression, intervening in the TLR4-NLRP3 inflammasome signaling pathway, and up-regulating expression of FOXO3a, MnSOD, OAT1, OAT3, OCT1, and OCT2 proteins. Thus, hesperetin could be a promising therapeutic agent against hyperuricemia.

Neferine ameliorates nonalcoholic steatohepatitis through regulating AMPK pathway.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD), peculiarly nonalcoholic steatohepatitis (NASH), has become the main cause of liver transplantation and liver-related death. However, the US Food and Drug Administration has not approved a specific medication for treating NASH. Neferine (NEF), a natural bisbenzylisoquinoline alkaloid separated from the traditional Chinese medicine Nelumbinis plumula, has a variety of pharmacological properties, especially on metabolic diseases. Nevertheless, the anti-NASH effect and mechanisms of NEF remain unclear. PURPOSE: This study aimed to investigate the amelioration of NEF on NASH and the potential mechanisms. STUDY DESIGN: HepG2 cells, hepatic stellate cells (HSCs) and high-fat diet (HFD)+carbon tetrachloride (CCl4) induced C57BL/6 mice were used to observe the effect of NEF against NASH and investigate the engaged mechanism. METHODS: HSCs and HepG2 cells stimulated by oleic acid (OA) were treated with NEF. C57BL/6 mice were fed with HFD+CCl4 to induce NASH mouse model and treated with or without NEF (5 mg/kg or 10 mg/kg, once daily, i.p) for 4 weeks. RESULTS: NEF significantly attenuated the accumulation of lipid droplets, intracellular triglyceride (TG) levels and hepatocytes apoptosis in OA-exposed HepG2 cells. NEF not only enhanced the AMPK and ACC phosphorylation in OA-stimulated HepG2 cells, but also reduced inflammatory response and fibrosis in lipopolysaccharide (LPS)-stimulated HepG2 and in LX-2, respectively. In HFD+CCl4-induced NASH mice, pathological staining confirmed NEF treatment mitigated hepatic lipid deposition, inflammatory cell infiltration as well as hepatic fibrosis. Furthermore, the liver weight, serum and hepatic TG and total cholesterol (TC) and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were decreased compared with the model group. HFD+CCl4 also induced the upregulation of specific proteins and genes associated to inflammation (ILs, TNF-α, NLRP3, ASC, CCL2 and CXCL10) and hepatic fibrosis (collagens, α-SMA, TGF-ß and TIPM1), which were also suppressed by NEF treatment. CONCLUSION: Our results demonstrated that NEF played a protective role in hepatic steatosis via the regulation of AMPK pathways, which may serve as an attractive candidate for a potential novel strategy on prevention and treatment of NASH.

Caffeine can alleviate non-alcoholic fatty liver disease by augmenting LDLR expression via targeting EGFR.

Increasing low-density lipoprotein receptor (LDLR) protein levels represents a key strategy for the prevention and treatment. Berberine can reportedly alleviate non-alcoholic fatty liver disease (NAFLD) by increasing the LDLR expression in an ERK1/2 signaling-dependent manner of NAFLD. Studies have shown that caffeine can inhibit fat deposition in the livers of mice; however, caffeine has not been reported to alleviate NAFLD by augmenting the LDLR expression via targeting EGFR. Here, an MTT assay, western blotting, RT-qPCR, immunohistochemistry, and surface plasmon resonance (SPR) analysis were used to investigate the role of caffeine in low-density lipoprotein cholesterol (LDL-C) clearance both in vitro and in vivo. In vitro, we found that caffeine could activate the EGFR-ERK1/2 signaling pathway in HepG2 cells, leading to increased LDLR mRNA and protein expression, and this effect could be inhibited by cetuximab. The SPR assay results have indicated that caffeine may increase the LDLR expression by directly binding to the EGFR extracellular domain and activating the EGFR-ERK1/2 signaling pathway. In vivo, caffeine markedly improved fatty liver and related blood indices in ApoE KO mice with high-fat-diet-induced NAFLD. Consistent with our in vitro results, we found that caffeine could also activate EGFR-ERK1/2 signaling and promote the LDLR expression in ApoE KO mice. In summary, caffeine can enhance the LDLR expression by directly binding to EGFR and activating the EGFR-ERK1/2 signaling pathway. EGFR signaling may represent a novel target for the prevention and treatment of NAFLD.

Dimeric-(-)-epigallocatechin-3-gallate inhibits the proliferation of lung cancer cells by inhibiting the EGFR signaling pathway.

Non-small cell lung cancer (NSCLC) is one of the most general malignant tumors. The overexpression of epidermal growth factor receptor (EGFR) is a common marker in NSCLC, and it plays an important role in the proliferation, invasion, and metastasis of cancer cells. At present, drugs developed with EGFR as a target suffer from drug resistance, so it is necessary to study new compounds for the treatment of NSCLC. The active substance in green tea is EGCG, which has anti-cancer effects. In this study, we synthesized dimeric-(-)-epigallocatechin-3-gallate (prodelphinidin B-4-3,3‴-di-O-gallate, PBOG), and explored the effect of PBOG on lung cancer cells. PBOG can inhibit the proliferation and migration of NCI-H1975 cells, promote cell apoptosis, and inhibit cell cycle progression. In addition, PBOG can bind to the EGFR ectodomain protein and change the secondary structure of the protein. At the same time, PBOG decreases the expression of EGFR and downstream protein phosphorylation. Animal experiments confirmed that PBOG can inhibit tumor growth by inhibiting EGFR phosphorylation. Collectively, our study results show that PBOG may induce a decrease in intracellular phosphorylated EGFR expression by binding to the EGFR ectodomain protein, thereby inducing apoptosis and inhibiting cell cycle progression, thus providing a new strategy to treat lung cancer.

20(S)-Protopanaxadiol decreases atherosclerosis in ApoE KO mice by increasing the levels of LDLR and inhibiting its binding with PCSK9.

Chinese medicinal and edible plants such as Panax notoginseng and ginseng are widely used for the treatment of atherosclerosis (AS). AS is the main pathological basis of cardiac-cerebral vascular disease, which seriously threatens human health and quality of life. Low-density lipoprotein (LDL) is the main pathogenic factor of AS. The LDL receptor (LDLR) is an important protein that functions to mediate the uptake and degradation of plasma LDL. Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) can mediate the internalization and degradation of LDLR. So, increasing the LDLR level by inhibiting PCSK9 is an important means of prevention and treatment of AS. In this study, by combining interaction technology (surface plasmon resonance, SPR) of small molecule compounds with membrane receptor proteins, cell experiments, and in vivo experiments, it is proved for the first time that 20(S)-protopanaxadiol (PPD), as a hydrolytic product of Panax notoginseng saponins in the intestinal tract, can bind to the extracellular domain of LDLR and inhibit the role of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in mediating LDLR degradation. The results showed that PPD significantly reduced aortic plaques and hepatic steatosis in HFD-fed ApoE KO mice. LDLR protein levels were elevated in the liver tissues isolated from PPD-treated HFD-fed ApoE KO mice and PPD-treated HepG2 cells. Our findings demonstrated that PPD significantly increased LDLR levels and reduced AS in the HFD-fed ApoE KO mice on account of LDLR degradation being inhibited by PPD inhibiting the interaction between PCSK9 and LDLR.

Structural characterization and biological evaluation of a new O-acetyl-1,4-linked-ß-d-mannan possessed potential application in hydrophilic polymer materials from Dendrobium devonianum.

To explore the active polysaccharides from Dendrobium devonianum, a novel O-acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)-ß-d-Manp-(1 â†’ (71.4%) residue with internal →4)-2-O-acetyl-ß-d-Manp-(1 â†’ (14.2%), →4)-3-O-acetyl-ß-d-Manp-(1 â†’ (7.1%), and non-reducing end ß-d-Manp-(1 â†’ (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF-α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials.

Discovery of EGFR-Targeted Environment-Sensitive fluorescent probes for cell imaging and efficient tumor detection.

Overexpression of human epidermal growth factor receptor (EGFR) plays an important role in several signaling pathways inside and outside the cell, especially in the processes of cell proliferation, differentiation, and death in various cancers. Due to the complexity of the structure and function of EGFR, research on the fluorescence visualization of EGFR protein visualization has proved challenging. One possible strategy for designing a receptor-targeting fluorescent probe with a switching mechanism is to introduce an environment-sensitive fluorophore into the drug ligand. Based on this strategic molecular design, we introduced two environment-sensitive small molecular fluorophores, dansyl chloride (DNS) and nitrobenzoxadiazole (NBD), to replace the morpholine group of gefitinib, achieving a series of fluorescent molecular probes bearing a switching mechanism. The GN probes exhibited prominent environment sensitivity, suggesting good performance as turn-on EGFR-targeting fluorescent ligands. The representative probe GN3 specifically responded to tumor cells overexpressing EGFR, which was validated with live-cell fluorescence imaging and in vivo xenograft tumor imaging. Ligand-induced EGFR phosphorylation in A431 cells was considerably inhibited by probe GN3, demonstrating that this probe still functions as an EGFR inhibitor. Owing to the turn-on response of GN3 to EGFR in tumor cells, and the competitive replacement behavior to the EGFR inhibitor gefitinib, these probes have the potential to be used for fluorescence imaging of cells overexpressing EGFR.

Synthesis and in vitro biological evaluation of novel dendrocandin analogue as potential anti-tumor agent.

Dendrocandins are characteristic chemical structures of D. officinale and have strong physiological bioactivities. In this study, a dendrocandin analogue (1) has been prepared by total synthesis (9 steps, 12.6% overall yield) in which coupling reaction and Wittig reaction as the key steps. Compound 1 was also evaluated for its anticancer activity in vitro against six human cancer cells (MCF-7, A549, A431, SW480, HepG-2 and HL-60) using MTT assays. Compound 1 showed potent cytotoxicity, with the IC50 value 16.27 ± 0.26 µM. The expression levels of apoptotic proteins indicated that compound 1 can up-regulate the expression of apoptotic proteins, leading to apoptosis. This compound suggested that it's potential as anticancer agent for further development.

Novel Perbutyrylated Glucose Derivatives of (-)-Epigallocatechin-3-Gallate Inhibit Cancer Cells Proliferation by Decreasing Phosphorylation of the EGFR: Synthesis, Cytotoxicity, and Molecular Docking.

Lung cancer is one of the most commonly occurring cancer mortality worldwide. The epidermal growth factor receptor (EGFR) plays an important role in cellular functions and has become the new promising target. Natural products and their derivatives with various structures, unique biological activities, and specific selectivity have served as lead compounds for EGFR. D-glucose and EGCG were used as starting materials. A series of glucoside derivatives of EGCG (7-12) were synthesized and evaluated for their in vitro anticancer activity against five human cancer cell lines, including HL-60, SMMC-7721, A-549, MCF-7, and SW480. In addition, we investigated the structure-activity relationship and physicochemical property-activity relationship of EGCG derivatives. Compounds 11 and 12 showed better growth inhibition than others in four cancer cell lines (HL-60, SMMC-7721, A-549, and MCF), with IC50 values in the range of 22.90-37.87 µM. Compounds 11 and 12 decreased phosphorylation of EGFR and downstream signaling protein, which also have more hydrophobic interactions than EGCG by docking study. The most active compounds 11 and 12, both having perbutyrylated glucose residue, we found that perbutyrylation of the glucose residue leads to increased cytotoxic activity and suggested that their potential as anticancer agents for further development.

Paenibacillus puerhi sp. nov., isolated from the rhizosphere soil of Pu-erh tea plants (Camellia sinensis var. assamica).

An aerobic, Gram-staining-positive, rod-shaped, endospore-forming and motile bacterial strain, designated SJY2T, was isolated from the rhizosphere soil of tea plants (Camellia sinensis var. assamica) collected in the organic tea garden of the Jingmai Pu-erh tea district in Pu'er city, Yunnan, southwest China. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the genus Paenibacillus. The closest phylogenetic relative was Paenibacillus filicis DSM 23916T (98.1% similarity). The major fatty acids (> 10% of the total fatty acids) were anteiso-C15:0 and isoC16:0. The major respiratory quinone was MK-7 and the major polar lipid was diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylmonomethylethanolamine. The peptidoglycan contained glutamic acid, serine, alanine and meso-diaminopimelic acid. Genome sequencing revealed a genome size of 6.71 Mbp and a G + C content of 53.1%. Pairwise determined whole genome average nucleotide identity (gANI) values and digital DNA-DNA hybridization (dDDH) values suggested that strain SJY2T represents a new species, for which we propose the name Paenibacillus puerhi sp. nov. with the type strain SJY2T (= CGMCC 1.17156T = KCTC 43242T).

Puerhibacterium puerhi gen. nov., sp. nov., a novel member of the family Promicromonosporaceae, isolated from Pu-erh tea pile-fermentation.

A Gram-staining positive aerobic bacterium, designated TLY-12T, was isolated from the Pu-erh tea pile-fermentation process in Pu'er city, Yunnan, China. Strain TLY-12T grew at 15-37 °C (optimum, 30 °C), pH 6.0-11.0 (optimum, pH 9.0) and 0-9.0% (w/v) NaCl (optimum, 3.0%). The major cellular fatty acids were anteiso-C15:0, C16:0 and iso-C16:0. The respiratory quinone were menaquinones MK-9 (H2) and MK-9 (H4). The polar lipids were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylinositol (PI), phosphoglycolipid (PGL), glycolipid (GL) and an unidentified phospholipid (PL). The peptidoglycan contained glutamic acid, aspartic acid, alanine and lysine, with the last named being the diagnostic diamino acid. Whole-cell sugars of the isolate were ribose, galactose and glucose. Phylogenetic analyses of 16S rRNA gene showed that this strain belonged to the family Promicromonosporaceae, and was most closely related to Isoptericola cucumis DSM 101603 T, which gave sequence similarity of 97.9%. Genome sequencing revealed a genome size of 3.91 Mbp and a G + C content of 75.0%. Average nucleotide identity and digital DNA-DNA hybridization values were all below the species threshold of described Promicromonosporaceae species. Genome phylogenetic analysis showed that strain TLY-12T formed a separate evolutionary branch, and was parallel to other related genera of Promicromonosporaceae. Based on the phylogenetic, phenotypic, chemotaxonomic and genome pairwise data, strain TLY-12T is considered to represent a novel species in a new genus in the family Promicromonosporaceae, for which the name Puerhibacterium puerhi gen. nov, sp. nov. is proposed. The type strain is TLY-12T (= CGMCC 1.17157T = KCTC 49467T).

Isoorientin exerts a urate-lowering effect through inhibition of xanthine oxidase and regulation of the TLR4-NLRP3 inflammasome signaling pathway.

Isoorientin (ISO), a natural flavonoid compound, has been identified in several plants and its biological activity is determined and the study on lowering uric acid has not been reported. In view of the current status of treatment of hyperuricemia, we evaluated the hypouricemic effects of ISO in vivo and in vitro, and explored the underlying mechanisms. Yeast extract-induced hyperuricemia animal model as well as hypoxanthine and xanthine oxidase (XOD) co-induced high uric acid L-O2 cell model and enzymatic experiments in vitro were selected. The XOD activity and uric acid (UA) level were inhibited after the treatment of ISO in vitro and in vivo. Furthermore, serum creatinine (CRE) and blood urea nitrogen (BUN) levels were also significantly reduced and liver damage was recovered in pathological histology after the ISO administration in hyperuricemia animal model. The results of mechanism illustrated that protein expressions such as XOD, toll-like receptor 4 (TLR4), cathepsin B (CTSB), NLRP3, and its downstream caspase-1 as well as interleukin-18 (IL-18) were markedly downregulated by ISO intervention in vitro and in vivo. Our results suggest that ISO exerts a urate-lowering effect through inhibiting XOD activity and regulating TLR4-NLRP3 inflammasome signal pathway, thus representing a promising candidate therapeutic agent for hyperuricemia. Both animal models and in vitro experiments suggested that ISO may effectively lower uric acid produce. The mechanism might be the inhibition of XOD activity and NLRP3 inflammasome of upregulation.

Synthesis, antitumor activity, and molecular docking of (-)-epigallocatechin-3-gallate-4ß-triazolopodophyllotoxin conjugates.

Two new (-)-epigallocatechin-3-gallate-4ß-triazolopodophyllotoxin conjugates (7 and 8) were synthesized and evaluated for biological activity. Compound 8 showed highly potent anticancer activity against A-549 cell line with IC50 of 2.16 ± 1.02 µM, which displayed the highest selectivity index value (SI = 14.5) in A-549 cells. Molecular docking indicated that compound 8 could bind with the active site of Top-II. Therefore, compound 8 might be a promising candidate for further development.

EGCG targeting Notch to attenuate renal fibrosis via inhibition of TGFß/Smad3 signaling pathway activation in streptozotocin-induced diabetic mice.

Renal fibrosis is a characteristic of diabetic nephropathy, which is a serious complication of diabetes. It has been reported that (-)-epigallocatechin gallate (EGCG) attenuates renal fibrosis. However, the molecular mechanism of regulation by EGCG in this process remains unclear. Previous studies showed that abnormal activation of Notch signaling contributes to the development of renal fibrosis. Previous studies have demonstrated that EGCG attenuates Notch1 expression. In this study, we found that the levels of fibronectin and Notch1 expression were decreased in human embryonic kidney cells after treatment with EGCG. We also observed that the type II transforming growth factor beta receptor (TGFßRII) and Smad3 pathway were inhibited in kidney cells by treatment with EGCG. In the diabetic kidney, we found that the activation of Notch signaling was attenuated by administration of EGCG. Moreover, TGFßRII and Smad3 phosphorylation could be inhibited by treatment with EGCG in the kidney. These results indicated that EGCG may improve renal fibrosis by targeting Notch via inhibition of the TGFß/Smad3 pathway in diabetic mice. Our findings provide insight into the therapeutic strategy for diabetes-induced renal fibrosis, and suggest EGCG to be a novel potential medicine for the treatment of chronic kidney disease in patients with diabetes.

Corrigendum: Dendrobium officinale Orchid Extract Prevents Ovariectomy-Induced Osteoporosis In Vivo and Inhibits RANKL-Induced Osteoclast Differentiation In Vitro.

[This corrects the article DOI: 10.3389/fphar.2017.00966.].

The oxidation of (-)-epigallocatechin-3-gallate inhibits T-cell acute lymphoblastic leukemia cell line HPB-ALL via the regulation of Notch1 expression.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy, and commonly associated with activating mutations in the Notch1 pathway. (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant and active catechin and has been shown to regulate Notch signaling. Taking into account the highly oxidizable and unstable of EGCG, we proposed that EGCG oxides may have greater potential to regulate Notch signaling than EGCG. In this study, we isolated and identified EGCG oxides (compound 2-4), using a chemical oxidation strategy, and evaluated for cytotoxicity against T-cell acute lymphoblastic leukemia cell line (HPB-ALL) by using the MTS assay. We found compound 3 significantly induced cell proliferation inhibition (38.3858 ± 1.67106 µM), cell apoptosis and cell cycle arrest in a dose-dependent manner. Remarkably, compound 3 inhibited expression of Notch1 compared with EGCG in HPB-ALL cells. Meanwhile, we found that compound 3 significantly inhibited c-Myc and Hes1, which are downstream target genes of Notch1. The findings demonstrate for the first time that an oxidation product of EGCG (compound 3) inhibits T-cell acute lymphoblastic leukemia cell line (HPB-ALL) and is a promising agent for cancer therapy deserving further research.

Wound healing can be improved by (-)-epigallocatechin gallate through targeting Notch in streptozotocin-induced diabetic mice.

Delayed wound healing is one of the most prominent clinical manifestations of diabetes and lacks satisfactory treatment options. Persistent inflammation occurs in the late phase of wound healing and impairs the healing process in mice with diabetes mellitus (DM). In this study, we observed that the late wound healing in streptozotocin (STZ)-induced DM mice could be improved by (-)-epigallocatechin gallate (EGCG). The macrophage accumulation, inflammation response, and Notch signaling can be inhibited by EGCG in the skin wounds of DM mice. Furthermore, we found that the LPS-induced inflammation response including overactivated Notch signaling, was inhibited by EGCG in mouse macrophages. Moreover, we confirmed that EGCG could directly bind with mouse Notch-1. In addition, our studies indicated that diabetic wound healing was improved by EGCG treatment before or after the inflammation phase by targeting the Notch signaling pathway, which suggests that the pre-existing diabetic wound healing can be improved by EGCG. To summarize, wound healing can be improved by EGCG through targeting Notch in STZ-induced DM mice. Our findings provide insight into the therapeutic strategy for diabetic wounds and offer EGCG as a novel potential medicine to treat chronic wounds.-Huang, Y.-W., Zhu, Q.-Q., Yang, X.-Y., Xu, H.-H., Sun, B., Wang, X.-J., Sheng, J. Wound healing can be improved by (-)-epigallocatechin gallate through targeting Notch in streptozotocin-induced diabetic mice.

1,4-ß-d-Glucomannan from Dendrobium officinale Activates NF-кB via TLR4 to Regulate the Immune Response.

2,3-O-acetylated-1,4-ß-d-glucomannan (DOP-1-1) is a polysaccharide isolated from the stem of Dendrobium officinale. DOP-1-1 has been demonstrated to have remarkable immunomodulatory properties, but little is known about the influence of its structural diversity on bioactivity (and even less about the exact mechanism underlying its immune responses). First, DOP-1-1 was stabilized at different temperatures and pH conditions based on differential scanning calorimetry and size exclusion-chromatography⁻high-performance liquid chromatography. Then, a detailed study on the effects of DOP-1-1 on a human leukemia monocytic cell line (THP-1) under normal conditions was undertaken. DOP-1-1 promoted the translocation of nuclear factor-kappa B (NF-κB) and degradation of IκB proteins. The expression of genes and proteins closely associated with the immune, survival and apoptotic functions of NF-κB were analyzed by quantitative real-time RT-PCR. Furthermore, CCL4 and IP10 were confirmed to be the novel targets of the immune response stimulated by DOP-1-1. The phosphorylation of NF-кB was inhibited by treatment with a toll-like receptor 4 (TLR4) antagonist (TAK-242) and myeloid differentiation factor 88 (MyD88) inhibitor (ST2825). These data suggested: (i) the O-acetylated glucomannan DOP-1-1 is present in the steady state in low-pH solutions; (ii) DOP-1-1 can induce an immune response through NF-кB mediated by a TLR4 signaling pathway; and (iii) CCL4 and IP10 could be the novel targets of the immune response stimulated by O-acetylated glucomannan.

Green tea (Camellia sinensis) aqueous extract alleviates postmenopausal osteoporosis in ovariectomized rats and prevents RANKL-induced osteoclastogenesis in vitro.

BACKGROUND: Green tea (Camelliasinensis [L.] Kuntze) belongs to the plant family Theaceae and is mainly distributed in East Asia, the Indian subcontinent and Southeast Asia. This plant has been proven to be beneficial to human health, and green tea is the second most consumed beverage in the world after water. However, until now, the effect of green tea aqueous extract (GTE) upon postmenopausal osteoporosis has remained unclear. In this study, we investigated the therapeutic effects of GTE on estrogen deficiency-induced osteoporosis and explored the possible mechanisms in vivo and in vitro. MATERIALS AND METHODS: Ovariectomized (OVX) female rats were orally administered with GTE at doses of 60, 120, and 370 mg kg-1 for 13 consecutive weeks. The biochemical parameters, bone gla protein, alkaline phosphatase, acid phosphatase, estrogen, interleukin-1ß, and interleukin-6 in blood samples were detected, and histological change in bones was analyzed by hematoxylin and eosin staining. Meanwhile, the mechanisms of GTE on osteoclast formation were explored in RAW 264.7 cells induced by receptor activation of the nuclear factor kappa B ligand (RANKL). RESULTS: The results showed that GTE could increase bone mass and inhibit trabecular bone loss in OVX rats. Furthermore, real-time quantitative reverse transcription polymerase chain reaction analysis from in vitro experiments also showed that GTE reduced the mRNA expression of osteoclast-associated genes such as cathepsin K (cath-K), c-Fos, matrix metalloproteinase 9, nuclear factor of activated T cells cytoplasmic 1 (NFATc1) and tartrate-resistant acid phosphatase. In addition, GTE caused a reduction in the protein levels of NFATc1, c-Fos, c-src and cath-K. CONCLUSION: Evidence from both animal models and in vitro experiments suggested that GTE might effectively ameliorate the symptoms of osteoporosis in OVX rats and inhibit RANKL-induced osteoclast-specific gene and protein expression.

Combined treatment with Dendrobium candidum and black tea extract promotes osteoprotective activity in ovariectomized estrogen deficient rats and osteoclast formation.

AIMS: Dendrobium candidum (DC) and black tea, are traditional chinese drinks, which contain multiple active ingredients. However, whether or not the combination of these two ingredients can improve osteoporosis remains unknown. This study therefore aimed to examine the effects of the combination of DC and black tea extract (BTE) on osteoporosis. MAIN METHODS: Ovariectomy (OVX)-induced osteoporosis in vivo as well as receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis in vitro was selected. KEY FINDINGS: Results showed that OVX rats that were treated orally with a DC and BTE combination for 12 weeks maintained their calcium (Ca) and phosphorus (P) homeostasis and exhibited significantly enhanced estradiol (E2) and OPG levels. This combination treatment also simultaneously reduced levels of interleukin (IL)-1ß, IL-6 and improved the organ coefficients of the uterus and femur as well as BMD and BMC in OVX rats. In addition, this DC and BTE combination suppressed osteoclast differentiation in the RANKL-stimulated osteoclastogenesis of RAW 264.7 cells and effectively inhibited the expression of osteoclast-associated genes and proteins. The results of this study further highlight the fact that a combination of DC and BTE improved ovariectomy-induced osteoporosis in rats and suppressed RANKL-stimulated osteoclastogenesis in RAW 264.7 cells. SIGNIFICANCE: This combination also significantly alleviated osteoporosis when compared to the alternative sole treatments above, due to synergistic effects among components. One partial mechanism of this combination might be the inhibition of osteoclast proliferation and the regulation of NFATC1/c-Fos expression.