Ethanol Extracts of Fresh Davallia formosana (WL1101) Inhibit Osteoclast Differentiation by Suppressing RANKL-Induced Nuclear Factor- κ B Activation

Euonymus alatus (Thunb.) Siebold Prevents Osteoclast Differentiation and Osteoporosis

Euonymus alatus (Thunb.) Siebold, a traditional medicinal plant, has been used in China and several other Asian countries to address a variety of health concerns. The extensive research conducted on E. alatus is driven by its diverse pharmacological applications. However, its biological effects on osteoclastogenesis and osteoporosis have not been previously studied. In this research, we investigated the impact of an ethanolic extract of E. alatus (EEEA) on osteoclast differentiation and function as well as estrogen deficiency-induced bone loss. We found that EEEA inhibits osteoclast differentiation by downregulating the expression of the receptor activator of nuclear factor-κB ligand (RANKL) in osteoclast-supporting cells and by directly impeding RANKL-mediated signaling pathways for osteoclastogenesis in precursor cells. In addition, EEEA inhibited the bone-resorptive function of mature osteoclasts in vitro. Furthermore, oral administration of EEEA significantly alleviated bone loss in an ovariectomy-induced osteoporosis mouse model. Additionally, we identified phytochemicals in EEEA that have suppressive effects on osteoclast differentiation and bone loss. Collectively, these results suggest that EEEA holds potential as a biotherapeutic candidate for anti-postmenopausal osteoporosis.

Eucommia, Cuscuta, and Drynaria Extracts Ameliorate Glucocorticoid-Induced Osteoporosis by Inhibiting Osteoclastogenesis Through PI3K/Akt Pathway

Osteoporosis is one of the most common diseases in the world which resulted in heavy socioeconomic burden and a public health threat. Glucocorticoid-induced osteoporosis (GIO) is the most common secondary reason of osteoporosis. Therapeutic strategies using traditional Chinese medicine are under investigation for osteoporosis, with efforts to improve efficacy and clarify the mechanism. The combination of Eucommia, Cuscuta, and Drynaria is widely used in traditional Chinese decoction for osteoporosis treatment, but the experimental efficacy and mechanism are still unclear. Administration of E.C.D. extracts (Eucommia, Cuscuta, and Drynaria) in experimental GIO rats resulted in decreased urinal calcium, phosphorus loss, and decreased expression of RANKL, CTX in serum, increased serum calcium, phosphorus, and OPG level. E.C.D. extracts also improved bone density, structural integrity, and biomechanical function in experimental GIO rats. These finding were associated with E.C.D. extracts’ treatment efficacy to GIO in vivo. The balance between osteoclast and osteoblast activity is essential for bone remodeling and bone related disease. The E.C.D. extracts inhibited Raw 264.7 cell differentiation to osteoclast in vitro. On the other hand, it promoted OPG expression of bone marrow mesenchymal stromal cells (MSCs) which can suppress the osteoclast genesis. E.C.D. extracts also increased the Wnt1 and Runx2 expression which are related to osteoblast formation. It also regulated the paracrine effect of MSC to inhibit osteoclast differentiation. The analysis of HPLC and comprehensive pharmacology identified the constituents of E.C.D. extracts and the potential osteoporosis-related targets mediated by E.C.D. extracts. The KEGG enrichment analysis suggested that PI3K/Akt pathway may be involved in the regulation osteoclast genesis by E.C.D. extracts and the result of Western blot of vitro assays proved it. Collectively, these data demonstrate E.C.D. extracts can inhibit osteoclast differentiation to foster experimental osteoporosis both in vivo and in vitro and it may exert the function of inhibiting osteoclast differentiation through PI3K/Akt pathway.

PERK activator CCT020312 prevents inflammation-mediated osteoporosis in the ovariectomized rats

OBJECTIVE

To investigate the therapeutic effects of PERK activator CCT020312 (CCT) on inflammation-mediated osteoporosis (IMO) in ovariectomized rats.

METHODS

Rats were divided into Sham, IMO, IMO + 1 mg/kg CCT and IMO + 2 mg/kg CCT groups. IMO models were constructed by bilateral ovariectomy (OVX) on 1st day followed by injection with magnesium silicate (Talc) on the 59th day. Sham rats did not undergo OVX surgery and were injected with saline instead of Talc. From 60th to 79th day, rats were treated with DMSO (vehicle control) in the Sham and IMO groups, and 1 or 2 mg/kg CCT020312 in treatment groups. Osteopontin (OPN), osteocalcin (OCN), tartrate-resistant acid phosphatase (TRAP), C-terminal telopeptide of type I collagen (CTX-I), and pro-inflammatory factors were measured on the 80th day. ProdigyDEXA was used to evaluate bone mineral density and content (BMD/BMC). Bone volume/total volume (BV/TV), connectivity density (Conn.D), trabecular number (Tb.N), and trabecular separation (Tb.Sp) was assessed using 3D micro-CT scanner.

RESULTS

CCT up-regulated Conn.D, BV/TV, and Tb.N, but down-regulated Tb.Sp in IMO rats. Besides, the declined femoral BMD and BMC in IMO rats were elevated after CCT treatment. Besides, IMO rats represented declined OPN and OCN, as well as increased TRAP, CTX-I, and pro-inflammatory factors, whereas those in the treatment groups were ameliorated regarding these indexes, with 2 mg/kg CCT showing better effect.

CONCLUSION

PERK activator CCT020312 can be served as a new therapeutic option for the protection against bone loss in the OVX rat model associated with inflammation probably by manipulating inflammatory factors.

Role of natural products in alleviation of rheumatoid arthritis-A review

Rheumatoid arthritis (RHA) is one of the most prevalent complex, chronic, inflammatory diseases, manifested by elevated oxidative stress and inflammatory biomarkers. Prolonged administration of NSAIDs, steroids, and DMARDs, used in the treatment of RHA, is associated with deleterious side effects. This necessitates the urge of new and safe approaches for RHA management, based on the complementary and alternative system of medicine. Documented evidences have suggested that supplementation with nutritional, dietary, and herbal components; can play a crucial role as an adjuvant, in the alleviation of the RHA symptoms, through their influence on the pathological inflammatory processes. Dietary phenolic compounds, flavonoids, carotenoids, and alkaloids with their ability to modulate prooxidant and pro-inflammatory pathways, have been effective in delaying the arthritic disease progression. Moreover, in scientific explorations, herbs containing phenolic compounds, alkaloids, carotenoids flavonoids, spices such as ginger, turmeric, Ayurvedic formulations, different diets such as Mediterranean diet, vegan diet, beverages, and oils such as sesame oil, rice bran oil, vitamins, and probiotics are proven to modulate the action of inflammatory molecules, involved in RHA pathology. Subsequently, the purpose of this review article is to summarize various in vitro, in vivo, and clinical studies in RHA, which have documented remarkable insights into the anti-inflammatory, antioxidant, analgesic, and immunomodulatory, bone erosion preventing properties of dietary, nutritional, and herbal components with the focus on their molecular level mechanisms involved in RHA. Even though major findings were derived from in vitro studies, several in vivo and clinical studies have established the use of diet, herbal, and nutritional management in RHA treatment. PRACTICAL APPLICATIONS: Thickening of the synovial membrane, bone erosion, and cartilage destruction is known to trigger rheumatoid arthritis causing inflammation and pain in bone joints. Continuous intake of NSAIDs, steroids, and DMARD therapy are associated with detrimental side effects. These side effects can be overcome by the use of dietary, nutritional, and herbal interventions based on the complementary and alternative therapy. This concept portrays the food components and other natural components having the potential to promote health, improve general well-being, and reduce the risk of RHA.

Chinese Herbal Formula Huayu-Qiangshen-Tongbi Decoction Compared With Leflunomide in Combination With Methotrexate in Patients With Active Rheumatoid Arthritis: An Open-Label, Randomized, Controlled, Pilot Study

Background: Traditional Chinese Medicine is complementary and an alternative to modern medicine. The combination therapies of herbal products with disease-modifying anti-rheumatic drugs are gradually and widely adopted in the management of rheumatoid arthritis (RA) in China. Purpose: To evaluate the efficacy and safety of Huayu-Qiangshen-Tongbi (HQT) decoction, a Chinese medicine formula, combined with methotrexate (MTX) in the treatment of patients with active RA, in comparison with the combination therapy of MTX with leflunomide (LEF). Methods: This pilot study was a monocenter, open-label, randomized controlled trial with two parallel arms. Ninety patients with active RA were randomly allocated to receive either HQT at a dose of 250 ml twice daily or LEF at a dose of 20 mg once daily, and all participants received MTX at a dose of 10-15 mg once weekly. The primary efficacy endpoint was the proportion of patients who achieved a 20% improvement in the American College of Rheumatology criteria (ACR20) after a 24-week treatment. Results: 84.4% (76/90) patients completed the 24-week observation. In the intention-to-treat analysis, the percentage values of patients achieving the ACR20 response criteria were 72.1% (31/43) in MTX + HQT group and 74.4% (32/43) in MTX + LEF group (p = 0.808). No significant difference was observed in other parameters, including ACR50, ACR70, clinical disease activity index good responses, European League Against Rheumatism good response, remission rate, and low disease activity rate. The results of the per-protocol analysis showed consistency with those of the intention-to-treat analysis. The mean change from baseline at week 24 for the van der Heijde modified total sharp score had no significant difference between two groups (3.59 ± 4.75 and 1.34 ± 8.67 in the MTX + HQT group and MTX + LEF group, respectively, p = 0.613). The frequency of adverse events was similar in both groups (11 cases in the MTX + HQT and 17 cases in the MTX + LEF, p > 0.05). Conclusions: In patients with active RA, treatment with the combination of HQT and MTX was associated with improvement in signs, symptoms, and physical function. With a beneficial clinical response and acceptable tolerability, HQT or other Chinese medicine formula may be a good therapeutic option in combination with MTX for RA treatment. Trial registration: Chinese Clinical Trails Registry, ChiCTR-INR-16009031, Registered on 15th August 2016, http://www.chictr.org.cn/enindex.aspx.

In Silico Interaction of the Active Compounds of Scurrula Atropurpurea with the RANK/RANKL/OPG System in Diabetoporosis

Introduction:

Diabetoporosis is a very complex health problem in Indonesia. One approach to the problem is through native Indonesian herbal medicine. The application of Scurrula atropurpurea in the treatment of diabetoporosis has not been revealed, so preliminary in silico study needs to be done.

Aim:

The purpose of the present study was to analyze the interaction between the active compound of Scurrula atropurpurea and the RANKL/RANK/OPG system in the pathomechanism of osteoporosis in diabetes mellitus.

Methods:

The procedures of the study included the search for the constituent amino acid of the RANK/RANKL/OPG system, the search for the structure of the active component of Scurrula atropurpurea, 3D modeling of protein structure, protein-ligand docking and visualization, and analysis of protein-ligand bonding interactions.

Results:

Those bond energies were RANKL-aviculin (–274.96 kJ/mol), RANKL-rutin (–263.12 kJ/mol), RANKL-quercitrin (–256.98 kJ/mol), RANKL-quercetin (–226,50 kJ/mol), RANKL-kaempferol (–221,65 kJ/mol), RANKL-catechin (–214,85 kJ/mol), RANKL-epicatechin (–211.66 kJ/mol), RANKL-caffeine (-171.73 kJ/mol), and RANKL-theobromine (-161.14 kJ/mol). The bond energies were RANK-rutin (-719.26 kJ/mol), RANK-catechin (-680.15 kJ/mol), RANK-caffeine (-654.48 kJ/mol), RANK-theobromine (-651.77 kJ/mol), RANK-quercitrin (-650.68 kJ/mol), RANK-kaempferol (-643.03 kJ/mol), RANK-epicatechin (-641.86 kJ/mol), RANK-quercetin (-641.76 kJ/mol), and RANK-aviculin (-628.62 kJ/mol). Those bond energies were OPG-epicatechin (-590.09 kJ/mol), OPG-theobromine (-578.08 kJ/mol), OPG-caffeine (-568.88 kJ/mol), RANKL-catechin (-560.63 kJ/mol), OPG-quercitrin (-554.50 kJ/mol), OPG-rutin (-547.91 kJ/mol), OPG-quercetin (-545.75 kJ/mol), OPG-kaempferol (-544.48 kJ/mol), and OPG-aviculin (-539.15 kJ/mol).

Conclusion:

The nine active ingredients of Scurrula atropurpurea do not interfere with the physiological function of RANKL to interact with RANK. The initial interaction of RANK with catechin or rutin will facilitate the bond of RANK to RANKL. When forming a complex with OPG, epicatechin will facilitate its interaction with RANKL.

Sirt1/Foxo Axis Plays a Crucial Role in the Mechanisms of Therapeutic Effects of Erzhi Pill in Ovariectomized Rats

Background. Erzhi pill (EZP), a traditional Chinese herbal formula, has been widely used to treat postmenopausal osteoporosis (PMOP) in China. However, its molecular mechanisms remain unclear. The aim of the present study is to investigate the antiosteoporotic effect of EZP on an ovariectomized rat model of PMOP. We performed the biomarkers of bone metabolism disorder, bone morphology, bone mineral density (BMD), and bone biomechanics to confirm the successful establishment of the PMOP model. We then investigated the expression of biomarkers related to the Sirt1/Foxo axis. We also examined microRNA-132 (miR-132), a regulator in the Sirtuin1 (Sirt1) expression. The bone metabolism disorder, bone morphology, BMD, and bone biomechanics in ovariectomized rats were improved by EZP administration. The antiosteoporotic effect of EZP was confirmed. We also found that the expressions of Sirt1, Runx2, Foxo1, and Foxo3a were downregulated in ovariectomized rats, while being then upregulated by EZP administration. And the expression of PPAR-γ and miR-132 was upregulated in ovariectomized rats and then downregulated by EZP administration. These results provided evidence that Sirt1/Foxo axis related mechanism may play a crucial role in the therapeutic effects of EZP, indicating that Sirt1/Foxo axis can be considered as a potential therapeutic target for PMOP in the future.

Isosteviol Derivative Inhibits Osteoclast Differentiation and Ameliorates Ovariectomy-Induced Osteoporosis

NC-8 (ent-16-oxobeyeran-19-N-methylureido) is an isosteviol-derived analogue with multiple biological effects, including anti-inflammation and anti-bacterial activities and inhibition of HBV viral surface antigen gene expression. In this study, we explored the effects of NC-8 on the formation of osteoclasts from RAW 264.7 cells. We found that NC-8 exerts the novel effect of inhibiting osteoclast-like cell formation. Our experiments showed that RANKL-induced ERK, p38, and JNK phosphorylation were inhibited by NC-8. An ovariectomy-induced osteoporosis animal model was used to examine the protective effects of oral treatment with NC-8. Serum analysis was used to examine markers of osteoblasts, osteoclasts, and renal and hepatic function in rats. Micro CT scanning and histological analysis were used to measure bone loss in ovariectomized rats. Oral administration of NC-8 effectively decreased excess bone resorption and significantly antagonized trabecular bone loss in ovariectomized rats. Serum analysis of C-terminal telopeptide of type-I collagen, an osteoclast marker, also showed that NC-8 administration inhibited excess bone resorption. Furthermore, serum analysis showed that renal and liver function were not affected by these doses of NC-8 during long-term treatment. Our results demonstrate that NC-8 inhibits osteoclast differentiation and effectively ameliorates ovariectomy-induced osteoporosis.

(-)-Epicatechin 3-O-β-D-allopyranoside prevent ovariectomy-induced bone loss in mice by suppressing RANKL-induced NF-κB and NFATc-1 signaling pathways

Background

Davallia formosana Hayata is a herb that has been used in Chinese medicine to treat bone diseases, including arthritis, bone fractures and osteoporosis. The rhizome of D. formosana H. has been found to be rich in (−)-Epicatechin 3-O-β-d-allopyranoside (ECAP), which is considered to be the active component of the plant in terms of its antiosteoporotic effect. This study investigated the molecular mechanism of the antiosteoporotic property of ECAP isolated from the roots of D. formosana H. using both in vitro and in vivo models.

Methods

We studied the effects of ECAP on the signaling pathways of the receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis and ovariectomy-induced osteoporosis. In the in vitro study, the inhibitory action of ECAP on RANKL-induced osteoclastogenesis and the expression of osteoclast-related marker genes were investigated, and in the in vivo study, the effects of ECAP on bone were evaluated using ovariectomized (OVX) mice orally-administered ECAP for 4 weeks.

Results

We demonstrated that ECAP dose-dependently inhibited RANKL- and nuclear factor of activated T-cells, and cytoplasmic 1 (NFATc-1)-induced osteoclastogenesis by RAW 264.7 cells, and reduced the extent of bone resorption. Furthermore, μCT images and TRAP staining showed that oral administration of ECAP to OVX mice prevented bone loss. ECAP administration also exerted recovery effects on serum C-terminal telopeptide of type I collagen and osteocalcin levels in OVX mice. In addition, we also found that MMP-9 expression was decreased in vivo and in vitro.

Conclusions

Overall, our findings suggested that ECAP suppresses RANKL-induced osteoclastogenesis through NF-κB and NFATc-1 signaling pathways, and has the potential for use in osteoporosis treatment.

Davallia bilabiata exhibits anti-angiogenic effect with modified MMP-2/TIMP-2 secretion and inhibited VEGF ligand/receptors expression in vascular endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Davallia bilabiata Hosokawa (D. bilabiata), also called GuSuiBu, is popularly used as a substitute for Drynaria fortunei J. Sm for rheumatoid and degenerative arthritis in traditional Chinese medicine. Little is known about the underlying mechanisms of anti-angiogenesis responsible for arthritis in D. bilabiata which needs to be elucidated.

AIM OF THE STUDY

The present study is intended to investigate the anti-angiogenic effect of D. bilabiata associated with the modulation of matrix metalloproteinases (MMPs) and down regulation of vascular endothelial growth factor (VEGF) ligand/receptors both in vivo and in vitro.

MATERIALS AND METHODS

We investigated the potential anti-angiogenic effect of D. bilabiata by the in vivo neovascularization of chick chorioallantoic membranes (CAM) assay, and the in vitro migration and matrix-induced tube formation assay using human umbilical vascular endothelial cells (HUVECs). The expressions of MMP-2, TIMP-2, RECK and VEGF/VEGFR were analyzed by real-time RT-PCR or Western blot method.

RESULTS

One major compound from water extract of D. bilabiata was identified as Epicatechin 3-O-β-D-allopyranoside. D. bilabiata was confirmed to inhibit in vivo angiogenesis by CAM assay. D. bilabiata also exhibited in vitro anti-angiogenic and anti-regrowth effects as demonstrated by tube formation assay, transwell migration assay and wound healing assay. The mRNA expressions of MMP-2, and MMP-14 were decreased. On the contrary, tissue inhibitor of metalloproteinase-2 (TIMP-2), reversion-inducing cysteine-rich protein with kazal motifs (RECK) were increased by D. bilabiata. The extracellular MMP-2 activity was found to be reduced both in vitro and in vivo by D. bilabiata as determined by gelatin zymography. Results from western blot analysis and ELISA further demonstrated the decrease of MMP-2 and increase of TIMP-2 secretion after D. bilabiata treatment. The gene expressions of VEGF-A, -B, -C, -D and VEGFR-1, -2, -3 were all inhibited by D. bilabiata.

CONCLUSION

We concluded that the anti-angiogenic effect of D. bilabiata was associated with the decreased MMP-2 activity mediated by the upregulation of TIMP-2 and RECK, and the suppression of VEGF/VEGFRs expression.

The treatment of rheumatoid arthritis using Chinese medicinal plants: From pharmacology to potential molecular mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Rheumatoid arthritis (RA) is a common worldwide public health problem. Traditional Chinese Medicine (TCM) achieved some results to some extent in the treatment of rheumatoid arthritis (RA). Especially in China, TCM formulas are used in the clinic because of their advantages. Some of these TCM formulas have been used for thousands of years in ancient China, they pays much attention to strengthening healthy qi, cleaning heat, and wet, activating blood, etc. So TCM in anti-RA drug is considered as a simple and effective method. In addition, TCM are also traditionally used as extracts and many Chinese herbs which are considered to be effective for RA. With the advancement of technologies and research methods, researchers have devoted themselves to exploring new therapeutic materials from troves of TCM. The components of TCM are identified and purified, which include alkaloids, coumarins, flavonoids, saponins and so on. However, little or no review works are found in the research literature on the anti-RA drugs from TCM. The present review aims to provide systematically reorganized information on the ethnopharmacology, phytochemistry and pharmacology of TCM used traditionally against RA. The information recorded in this review will provide new directions for researchers in the future.

MATERIALS AND METHODS

Relevant scientific literatures were collected from Chinese traditional books and Chinese Pharmacopoeia. Several important pharmacology data, clinical observations, animal experiments on effects of anti-RA drugs from TCM and their mechanisms were extracted from a library and electric search (Pubmed, PubChem Compound, Science Direct, Spring Link, Elsevier, Web of Science, CNKI, Wan Fang, Bai du, The Plant List, etc.). We collected information published between 2002 and 2015 on Chinese medicine in the treatment of RA. Information was also acquired from local classic herbal literature, conference papers, government reports, and PhD and MSc dissertations.

RESULTS

This review mainly introduces the current research on anti-RA TCM formulas, extracts and compounds from TCM, pharmacological data and potential mechanisms (inhibit osteoclast proliferation, suppress fibroblast-like synoviocytes (FLSs) growth, decrease the expression of inflammatory cytokines, blocking signal pathways, etc.).

CONCLUSIONS

TCM, as a multi-component and multi-target approach, which is a perfect match with the holistic concept of systems biology, is applicable in the treatment of RA. The synergistic connections of Chinese herbs and mechanisms of related active compounds on RA increase the trust for TCM. TCM as alternative remedies for RA not only has an important position in the world market, but also has an irreplaceable role in the treatment of RA in future.