Effect of gut hormones on bone metabolism and their possible mechanisms in the treatment of osteoporosis.

Bone is a highly dynamic organ that changes with the daily circadian rhythm. During the day, bone resorption is suppressed due to eating, while it increases at night. This circadian rhythm of the skeleton is regulated by gut hormones. Until now, gut hormones that have been found to affect skeletal homeostasis include glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), glucose-dependent insulinotropic polypeptide (GIP), and peptide YY (PYY), which exerts its effects by binding to its cognate receptors (GLP-1R, GLP-2R, GIPR, and Y1R). Several studies have shown that GLP-1, GLP-2, and GIP all inhibit bone resorption, while GIP also promotes bone formation. Notably, PYY has a strong bone resorption-promoting effect. In addition, gut microbiota (GM) plays an important role in maintaining bone homeostasis. This review outlines the roles of GLP-1, GLP-2, GIP, and PYY in bone metabolism and discusses the roles of gut hormones and the GM in regulating bone homeostasis and their potential mechanisms.

Integration of network pharmacology with experimental validation to reveal the mechanism of action of Longdan Xiegan Decoction against HSV2 infection and determine its effective components.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese Medicine (TCM) has made enormous strides recently in the discovery of anti-herpes simplex virus (HSV) drugs under the guidance of TCM theory. Longdan Xiegan Decoction (LXD), a formulation recorded in the Pharmacopoeia of the People's Republic of China, has proved to be effective against HSV infection. However, its effective components and action mechanism remain unclear. AIM OF THE STUDY: To investigate the effective components and mechanisms of LXD in treating HSV infection based on network pharmacology and experimental validation. MATERIALS AND METHODS: The anti-HSV activities of key compounds predicted by network analysis were detected by antiviral tests. High-performance liquid chromatography (HPLC) was applied to identify the main components of the LXD aqueous extract. Time-of-addition assay and infectivity inhibition reversibility assay were conducted to identify the potential antiviral mechanisms of licochalcone B (LCB). Additionally, we assessed the antiviral effect of LCB in vivo by use of body weight, viral load, histological analysis, and scoring of genital lesions in an HSV2-infected mouse model. RESULTS: Our data demonstrated that some components exhibited significant anti-HSV1/2 activity in vitro, including quercetin, kaempferol, wogonin, formononetin, naringenin, baicalein, isorhamnetin, glabridin, licochalcone A, echinatin, oroxylin A, isoliquiritigenin, pinocembrin, LCB and acacetin. HPLC analysis showed that LCB was the main component of LXD aqueous extract. In vitro experiments revealed that LCB not only inactivated HSV2 particles, but also inhibited HSV2 multiplication through the inhibition of the phosphorylation of Akt and its downstream targets. In vivo experiments confirmed that LCB could significantly reduce viral titer, delay weight loss, and alleviate pathological changes in vaginal tissue in vaginal infection mouse models. CONCLUSION: LCB acted as the main component of LXD, with significant anti-HSV2 infection effects both in vivo and in vitro. This study provides additional evidence of the healing efficacy of LXD against HSV infection and presents an efficient analytical method for further investigation of the mechanisms of TCM in prevention and treatment of various diseases.

Salidroside alleviates dexamethasone-induced inhibition of bone formation via transforming growth factor-beta/Smad2/3 signaling pathway.

Glucocorticoid-induced osteoporosis is the third epidemic osteoporosis following postmenopausal and senileosteoporosis. According to one study, salidroside made ovariectomized rats' bones strong. Salidroside's potential for treating glucocorticoid-induced osteoporosis remains unproven. This study aimed to investigate the protective effect and mechanism of salidroside on dexamethasone-induced osteogenic differentiation and bone formation in MC3T3-E1 cells and zebrafish. The study proved that salindroside had no harmful impact on MC3T3E1 cells. Salidroside significantly relieved dexamethasone-induced inhibition of ALP (alkaline phosphatase) activity and mineralization in MC3T3-E1 cells, and promoted osteogenic differentiation of cells. Salidroside increased the expression of osteopontin (OPN), runt-related transcription factor 2 (Runx2), osterix (Osx), transforming growth factor-beta (TGF-ß) proteins and promoted the phosphorylation of Smad2/3 in MC3T3-E1 cells treated with dexamethasone. In addition, the effect of salidroside in relieving dexamethasone-induced inhibition of osteogenic differentiation in MC3T3-E1 cells can be blocked by TGF-ß receptor type I/II inhibitor (LY2109761). At the same time, we found that salidroside significantly alleviated the inhibition of dexamethasone-induced bone formation in zebrafish and promoted the mineralization of zebrafish skulls. LY2109761 reversed the protective impact of salidroside on dexamethasone-mediated bone impairment in zebrafish. These findings suggested that salidroside alleviated dexamethasone-induced inhibition of osteogenic differentiation and bone formation via TGF-ß/Smad2/3 signaling pathway.

Correction: Zheng et al. Geniposide Ameliorated Dexamethasone-Induced Cholesterol Accumulation in Osteoblasts by Mediating the GLP-1R/ABCA1 Axis. Cells 2021, 10, 3424.

The authors wish to make the following changes to their paper [...].

Identification of phytochemicals in Qingfei Paidu decoction for the treatment of coronavirus disease 2019 by targeting the virus-host interactome.

Qingfei Paidu decoction (QFPDD) has been clinically proven to be effective in the treatment of coronavirus disease 2019 (COVID-19). However, the bioactive components and therapeutic mechanisms remain unclear. This study aimed to explore the effective components and underlying mechanisms of QFPDD in the treatment of COVID-19 by targeting the virus-host interactome and verifying the antiviral activities of its active components in vitro. Key active components and targets were identified by analysing the topological features of a compound-target-pathway-disease regulatory network of QFPDD for the treatment of COVID-19. The antiviral activity of the active components was determined by a live virus infection assay, and possible mechanisms were analysed by pseudotyped virus infection and molecular docking assays. The inhibitory effects of the components tested on the virus-induced release of IL-6, IL-1ß and CXCL-10 were detected by ELISA. Three components of QFPDD, oroxylin A, hesperetin and scutellarin, exhibited potent antiviral activities against live SARS-CoV-2 virus and HCoV-OC43 virus with IC50 values ranging from 18.68 to 63.27 µM. Oroxylin A inhibited the entry of SARS-CoV-2 pseudovirus into target cells and inhibited SARS-CoV-2 S protein-mediated cell-cell fusion by binding with the ACE2 receptor. The active components of QFPDD obviously inhibited the IL-6, IL-1ß and CXCL-10 release induced by the SARS-CoV-2 S protein. This study supports the clinical application of QFPDD and provides an effective analysis method for the in-depth study of the mechanisms of traditional Chinese medicine (TCM) in the prevention and treatment of COVID-19.

Novel Sigma-2 receptor ligand A011 overcomes MDR in adriamycin-resistant human breast cancer cells by modulating ABCB1 and ABCG2 transporter function.

Multidrug resistance (MDR) is thought to be one of the main reasons for the failure of chemotherapy in cancers. ATP-binding cassette subfamily B member 1 (ABCB1) or P-glycoprotein (P-gp) and ATP-binding cassette subfamily G member 2 (ABCG2) play indispensable roles in cancer cell MDR. Sigma-2 (σ2) receptor is considered to be a cancer biomarker and a potential therapeutic target due to its high expression in various proliferative tumors. Recently, σ2 receptor ligands have been shown to have promising cytotoxic effects against cancer cells and to modulate the activity of P-glycoprotein (ABCB1) in vitro experiments, but their specific effects and mechanisms remain to be elucidated. We found that A011, a σ2 receptor ligand with the structure of 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline, showed promising cytotoxicity against breast cancer MCF-7 and adriamycin-resistant MCF-7 (MCF-7/ADR), induced apoptosis, and reversed adriamycin (ADR) and paclitaxel resistance in MCF-7/ADR cells. Furthermore, we demonstrated that A011 increased the accumulation of rhodamine 123 and mitoxantrone in MCF-7/ADR cells. A011 significantly decreased the ATPase activity of the ABCB1 and down-regulated ABCG2 protein expression. In addition, A011, administered alone or in combination with ADR, significantly inhibited tumor growth in the MCF-7/ADR tumor-bearing nude mouse model. A011 may be a potential therapeutic agent for the treatment of tumor resistance.

A011, a novel small-molecule ligand of σ2 receptor, potently suppresses breast cancer progression via endoplasmic reticulum stress and autophagy.

Breast cancer has surpassed lung cancer to become the most commonly diagnosed cancer in women worldwide. Sigma-2 (σ2) receptor is considered to be a potential therapeutic target for breast cancer because of its high expression in breast cancer cells and low expression in normal breast cells. Many σ2 ligands have been reported to have excellent anticancer activity, but their mechanism of action has not been fully elucidated. We discovered that A011 had high affinity and selectivity for σ2 receptor, reduced proliferation in five cancer cell lines, and significantly inhibited the monoclonal formation ability of MCF-7 cells. Furthermore, A011 rapidly increased the levels of intracellular Ca2+ and reactive oxygen species and induced autophagy. Molecular pharmacology studies revealed that A011 induced endoplasmic reticulum stress, activated the PERK-eIF2α-CHOP pathway and inhibited the activation of the PI3K-Akt-mTOR pathway, leading to cell apoptosis. In an in vivo tumor model, A011 showed obvious anti-tumor activity and no significant toxicity. More importantly, our study demonstrated for the first time that endoplasmic reticulum stress is the main mechanism of anti-cancer effects for σ2 ligands, at least for A011. A011 may potentially be useful as a therapeutic agent for treating breast cancer.

Geniposide Ameliorated Dexamethasone-Induced Cholesterol Accumulation in Osteoblasts by Mediating the GLP-1R/ABCA1 Axis.

BACKGROUND: Overexposure to glucocorticoid (GC) produces various clinical complications, including osteoporosis (OP), dyslipidemia, and hypercholesterolemia. Geniposide (GEN) is a natural iridoid compound isolated from Eucommia ulmoides. Our previous study found that GEN could alleviate dexamethasone (DEX)-induced differentiation inhibition of MC3T3-E1 cells. However, whether GEN protected against Dex-induced cholesterol accumulation in osteoblasts was still unclear. METHODS: DEX was used to induce rat OP. Micro-CT data was obtained. The ALP activity and mineralization were determined by the staining assays, and the total intracellular cholesterol was determined by the ELISA kits. The protein expression was detected by western blot. RESULTS: GEN ameliorated Dex-induced micro-structure damages and cell differentiation inhibition in the bone trabecula in rats. In MC3T3-E1 cells, Dex enhanced the total intracellular cholesterol, which reduced the activity of cell proliferation and differentiation. Effectively, GEN decreased DEX-induced cholesterol accumulation, enhanced cell differentiation, and upregulated the expression of the GLP-1R/ABCA1 axis. In addition, inhibition of ABAC1 expression reversed the actions of GEN. Treatment with Exendin9-39, a GLP-1R inhibitor, could abrogate the protective activity of GEN. CONCLUSIONS: GEN ameliorated Dex-induced accumulation of cholesterol and inhibition of cell differentiation by mediating the GLP-1R/ABCA1 axis in MC3T3-E1 cells.

Kaempferol Ameliorates the Inhibitory Activity of Dexamethasone in the Osteogenesis of MC3T3-E1 Cells by JNK and p38-MAPK Pathways.

Kaempferol has been reported to exhibit beneficial effect on the osteogenic differentiation in mesenchymal stem cells (MSC) and osteoblasts. In our previous study, dexamethasone (DEX) demonstrated inhibitory effect on MC3T3-E1 cells differentiation. In this study, we mainly explored the protective effect of kaempferol on the inhibitory activity of DEX in the osteogenesis of MC3T3-E1 cells. We found that kaempferol ameliorated the proliferation inhibition, cell cycle arrest, and cell apoptosis and increased the activity of alkaline phosphatase (ALP) and the mineralization in DEX-treated MC3T3-E1 cells. Kaempferol also significantly enhanced the expression of osterix (Osx) and runt-related transcription factor 2 (Runx2) in MC3T3-E1 cells treated with DEX. In addition, kaempferol attenuated DEX-induced reduction of cyclin D1 and Bcl-2 expression and elevation of p53 and Bax expression. Kaempferol also activated JNK and p38-MAPK pathways in DEX-treated MC3T3-E1 cells. Furthermore, kaempferol improved bone mineralization in DEX-induced bone damage in a zebrafish larvae model. These data suggested that kaempferol ameliorated the inhibitory activity of DEX in the osteogenesis of MC3T3-E1 cells by activating JNK and p38-MAPK signaling pathways. Kaempferol exhibited great potentials in developing new drugs for treating glucocorticoid-induced osteoporosis.

5,7,3',4'-tetramethoxyflavone ameliorates cholesterol dysregulation by mediating SIRT1/FOXO3a/ABCA1 signaling in osteoarthritis chondrocytes.

Dyslipidemia has been associated with the development of osteoarthritis. Our previous study found that 5,7,3',4'-tetramethoxyflavone (TMF) exhibited protective activities against the pathological changes of osteoarthritis. Aim: To investigate the roles of TMF in regulating ABCA1-mediated cholesterol metabolism. Methods: Knockdown and overexpression were employed to study gene functions. Protein-protein interaction was investigated by co-immunoprecipitation, and the subcellular locations of proteins were studied by immunofluorescence. Results: IL-1ß decreased ABCA1 expression and induced apoptosis. Therapeutically, TMF ameliorated the effects of IL-1ß. FOXO3a knockdown expression abrogated the effects of TMF, and FOXO3a overexpression increased ABCA1 expression by interacting with LXRα. TMF promoted FOXO3a nuclear translocation by activating SIRT1 expression. Conclusions: TMF ameliorates cholesterol dysregulation by increasing the expression of FOXO3a/LXRα/ABCA1 signaling through SIRT1 in C28/I2 cells.

Synthesis, binding, and functional properties of tetrahydroisoquinolino-2-alkyl phenones as selective σ2R/TMEM97 ligands.

Sigma-2 receptor (σ2R/TMEM97) has been implicated to play important roles in multiple cellular dysfunctions, such as cell neoplastic proliferation, neuro-inflammation, neurodegeneration, etc. Selective σ2 ligands are believed to be promising pharmacological tools to regulate or diagnose various disorders. As an ongoing effort of discovery of new and selective σ2 ligands, we have synthesized a series of tetrahydroisoquinolino-2-alkyl phenone analogs and identified that 10 of them have moderate to potent affinity and selectivity for σ2R/TMEM97. Especially, 4 analogs showed Ki values ranging from 0.38 to 5.1 nM for σ2R/TMEM97 with no or low affinity for sigma-1 receptor (σ1R). Functional assays indicated that these 4 most potent analogs had no effects on intracellular calcium concentration and were classified as putative σ2R/TMEM97 antagonists according to current understanding. The σ2R/TMEM97 has been suggested to play important roles in the central nervous system. Based on published pharmacological and clinical results from several regarded σ2R/TMEM97 antagonists, these analogs may potentially be useful for the treatment of various neurodegenerative diseases.

Cycloastragenol protects against glucocorticoid-induced osteogenic differentiation inhibition by activating telomerase.

Glucocorticoid-induced osteoporosis (GIOP) that is mainly featured as low bone density and increased risk of fracture is prone to occur with the administration of excessive glucocorticoids. Cycloastragenol (CAG) has been verified to be a small molecule that activates telomerase. Studied showed that up-regulated telomerase was associated with promoting osteogeneic differentiation, so we explored whether CAG could promote osteogenic differentiation to protect against GIOP and telomerase would be the target that CAG exerted its function. Our results demonstrated that CAG prominently increased the ALP activity, mineralization, mRNA of runt-related transcription factor 2, osteocalcin, osteopontin, collagen type I in both MC3T3-E1 cells and dexamethasone (DEX)-treated MC3T3-E1 cells. CAG up-regulated telomerase reverse transcriptase and the protective effect of CAG was blocked by telomerase inhibitor TMPyP4. Moreover, CAG improved bone mineralization in DEX-induced bone damage in a zebrafish larvea model. Therefore, the study showed that CAG could alleviate the osteogenic differentiation inhibition induced by DEX in vitro and in vivo, and CAG might be considered as a candidate drug for the treatment of GIOP.

Prediction of the mechanisms of Xiaoai Jiedu Recipe in the treatment of breast cancer: A comprehensive approach study with experimental validation.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese medicine (TCM) holds a great promise for preventing complex chronic diseases through a holistic way. Certain Chinese medicine formulae from TCM are effective for treating and preventing cancer in clinical practice. Xiaoai Jiedu Recipe (XJR) is a Chinese medicine formula that has been used to treat breast cancer (BC). However, its active ingredients and therapeutic mechanisms on tumor are unclear. Therefore, further investigation is necessary. AIM OF THE STUDY: This study aims to elucidate the active compounds of XJR and its molecular mechanisms for the treatment of BC. MATERIALS AND METHODS: A comprehensive approach was used to clarify the pharmacodynamic basis of XJR and its pharmacological mechanism, including the acquisition of differentially expressed genes of BC, screening of active ingredients and their targets, construction of complex internetwork between drugs and diseases, and analysis of the key subnetwork. Finally, these results were validated by in vitro experiments and comparison with literature reviews. RESULTS: By using bioinformatics, 5211 differentially expressed genes of BC were identified, more than half of them had been reported in previous studies. By using network analysis, 113 potential bioactive compounds in the ten component herbs of XJR and 157 BC-related targets were identified, which were significantly enriched in 85 pathways and 1321 GO terms. The in vitro studies showed that quercetin and ursolic acid, the active components of XJR, could effectively inhibit the proliferation of breast cancer cells, and the combination of the two components could significantly decrease the mitochondrial membrane potential and suppress the activation of PI3K-Akt signaling pathway, thus inducing apoptosis of cancer cells. CONCLUSIONS: XJR played an important role in anti-BC through multi-component, multi-target and multi-pathway mechanisms, in which quercetin and ursolic acid may be the key active components. The anticancer effect of multi-component application was better than that of a single component. This study not only deepened our understanding of the role of TCM in the prevention and treatment of diseases, but also provided a reference for the in-depth research, development and application of the ancient medicine.

Unravel the molecular mechanism of XBP1 in regulating the biology of cancer cells.

Cancer cells are usually exposed to stressful environments, such as hypoxia, nutrient deprivation, and other metabolic dysfunctional regulation, leading to continuous endoplasmic reticulum (ER) stress. As the most conserved branch among the three un-folded protein response (UPR) pathways, Inositol-requiring enzyme 1α (IRE1α)-X-box-binding protein 1 (XBP1) signaling has been implicated in cancer development and progression. Active XBP1 with transactivation domain functions as a transcription factor to regulate the expression of downstream target genes, including many oncogenic factors. The regulatory activity of XBP1 in cell proliferation, apoptosis, metastasis, and drug resistance promotes cell survival, leading to tumorigenesis and tumor progression. In addition, the XBP1 peptides-based vaccination and/or combination with immune-modulatory drug administration have been developed for effective management for several cancers. Potentially, XBP1 is the biomarker of cancer development and progression and the strategy for clinical cancer management.

Geniposide Alleviates Glucocorticoid-Induced Inhibition of Osteogenic Differentiation in MC3T3-E1 Cells by ERK Pathway.

Glucocorticoid (GC) therapy is the leading cause of secondary osteoporosis and the therapeutic and preventative drugs for GC-induced osteoporosis are limited. In this study, we investigated the protective effects of geniposide on dexamethasone (DEX)-induced osteogenic inhibition in MC3T3-E1 cells. The results showed that there was no obvious toxicity on MC3T3-E1 cells when geniposide was used at the doses ranging from 1 to 75 µM. In DEX-treated MC3T3-E1 cells, geniposide promoted the alkaline phosphatase (ALP) activity and the mineralization. In addition, geniposide also significantly increased the mRNA and protein expression of osteopontin (OPN), Runt-related transcription factor 2 (Runx2), and Osterix (Osx) in DEX-treated MC3T3-E1 cells. Furthermore, geniposide activated ERK pathway in DEX-treated MC3T3-E1 cells. The ERK activation inhibitor U0126 and glucagon-like peptide-1 (GLP-1) receptor antagonist exendin 9-39 abolished the geniposide-induced activation of ERK and inhibited the protective effect of geniposide. Taken together, our study revealed that geniposide alleviated GC-induced osteogenic suppression in MC3T3-E1 cells. The effect of geniposide was at least partially associated with activating ERK signaling pathway via GLP-1 receptor. Geniposide might be a potential therapeutic agent for GC-induced osteoporosis.

[Systematic review of Shenqi Fuzheng Injection combined with chemotherapy for treatment of breast cancer].

Databases including China Biological Medicine database(CBM), Chinese scientific journals full-text database(VIP), China National Knowledge Infrastructure database(CNKI), WanFang Data, PubMed, and EMbase were searched from inception to March 2018 to collect the randomized controlled trials(RCTs) on Shenqi Fuzheng Injection combined with chemotherapy for the treatment of breast cancer. All included studies were critically appraised by two independent reviewers by following the cochrane systematic review method and using Revman 5.3 software and State 12.0 for data analysis. After screening, 20 RCTs involving 2 095 patients were included in the study. Meta-analysis showed that as compared with control group of chemotherapy alone, Shenqi Fuzheng Injection combined with chemotherapy could improve the clinical curative efficiency, the KPS score, and immune function indexes such as total T cells, Th cells and Ts cells; inhibit the decline of white blood cells(WBC), platelets in blood system, T-lymphocyte subsets such as CD3~+, CD4~+, CD4~+/CD8~+, alleviate myelosuppression and reduce the incidence of side effects such as gastrointestinal adverse reaction, liver and kidney dysfunction and abnormal electrocardiogram. The results revealed that for clinical breast cancer patients, Shenqi Fuzheng Injection combined with chemotherapy could significantly improve its clinical efficacy and reduce adverse reactions. However, the conclusions still need to be verified by high-quality, multi-center, large-sample, prospective, randomized and double-blind clinical trials. In conclusion, this study has systemically evaluated the efficacy and safety of Shenqi Fuzheng Injection combined with chemotherapy in treatment of breast cancer and provided the reference of evidence-based medicine for safe and effective clinical application of medicines.

Biological activity and health promoting effects of psoralidin.

Psoralidin, a prenylated coumestrol isolated from the seed of a traditional Chinese medicine Psoralea corylifolia L., has been demonstrated to exhibit anti-inflammatory, anti-cancer, anti-oxidative, estrogenic, neuroprotective, anti-bacterial, and anti-parasite activities. Due to prenylation, psoralidin exhibits stronger estrogenic activity with no obvious adverse effects and shows a close association with management of osteoporosis and some cancers. However, the hydrophobicity and low bioavailability of psoralidin limit its clinical application, although recent investigation has gained valuable data. This review will discuss the biological activities of psoralidin in health.

Isolation, synthesis, and cytotoxicity evaluation of two impurities in nomegestrol acetate.

Nomegestrol acetate (NOMAc) is a synthetic progesterone analog and classified as a fourth-generation progestin. It has been approved in many countries for oral contraception, hormonal replacement therapy (HRT), and treatment of various gynecological disorders. There are several synthetic routes reported for the synthesis of NOMAc and they all share the very similar last three to five steps toward the conversion of 6-methylene to 6-methyl-6,7-unsaturated structure. Therefore the final product from different processing routes may have similar impurity profiles. In the analysis of NOMAc, we identified two impurities, impurity A (listed in EP 8.0) and impurity B (not specified in EP 8.0). Both impurities were further confirmed by synthesis. In addition, both impurities and NOMAc were evaluated for their in vitro cytotoxicities against L02 liver cells, mesenchymal stem cells, MCF-7 breast cancer cells, and C33A cervical cancer cells. These three analogs are not cytotoxic to the four cell lines at low concentrations (<20 µM). NOMAc and impurity A showed cytotoxicity to L02, MCF-7, and C33A cells at high concentrations, while impurity B did not show significant cytotoxicity to any of the cell lines tested.