Osteoprotective Effect of Echinocystic Acid, a Triterpone Component from Eclipta prostrata, in Ovariectomy-Induced Osteoporotic Rats

Echinocystic acid activates PPARγ to alleviate mannan-induced psoriasis and psoriatic arthritis in mice

Previous studies have shown that echinocystic acid (EA) can reduce arthritis and skin damage, but the role of EA in psoriatic arthritis is unclear. This study aims to prove the role of EA in psoriatic arthritis, which was induced by intraperitoneal injection of mannan in C57BL/6J mice. The mice were divided into a control group, mannan group, mannan + EA (low-dose) group, and mannan + EA (high-dose) group. Joint tissue damage was scored, and pathological changes in joint tissue and ear skin damage were examined by HE staining. Pathway enrichment of EA drug targets was performed through the target enrichment website, and the mRNA and protein expression levels of pathway-related proteins in joint tissues and ears were verified using the PCR and western blot. The results show that injection of mannan into mice resulted in joint inflammatory infiltration and tissue damage, hyperkeratosis, and acanthosis of the ear skin, while these symptoms were alleviated after high-dose EA treatment. Pathway enrichment analysis showed that the EA drug treatment target is concentrated on the PPAR pathway. The mRNA and protein results showed that the mRNA and protein expression levels of peroxisome proliferator-activated receptor γ (PPARγ) in the joint tissues and ears of mice with psoriatic arthritis decreased, and the expression of PPARγ was activated after high-dose EA treatment. In conclusion, EA increases PPARγ expression and reduces joint and skin damage in mice with psoriatic arthritis.

Indoxyl sulfate exacerbates alveolar bone loss in chronic kidney disease through ferroptosis

OBJECTIVES

The purpose of this study was to determine whether indoxyl sulfate (IS) is involved in alveolar bone deterioration and to elucidate the mechanism underlying alveolar bone loss in chronic kidney disease (CKD) patients.

MATERIALS AND METHODS

Mice were divided into the control group, CP group (ligature-induced periodontitis), CKD group (5/6 nephrectomy), and CKD + CP group. The concentration of IS in the gingival crevicular fluid (GCF) was determined by HPLC. The bone microarchitecture was evaluated by micro-CT. MC3T3-E1 cells were stimulated with IS, and changes in mitochondrial morphology and ferroptosis-related factors were detected. RT-PCR, western blotting, alkaline phosphatase activity assays, and alizarin red S staining were utilized to assess how IS affects osteogenic differentiation.

RESULTS

Compared with that in the other groups, alveolar bone destruction in the CKD + CP group was more severe. IS accumulated in the GCF of mice with CKD. IS activated the aryl hydrocarbon receptor (AhR) in vitro, inhibited MC3T3-E1 cell osteogenic differentiation, caused changes in mitochondrial morphology, and activated the SLC7A11/GPX4 signaling pathway. An AhR inhibitor attenuated the aforementioned changes induced by IS.

CONCLUSIONS

IS activated the AhR/SLC7A11/GPX4 signaling pathway, inhibited osteogenesis in MC3T3-E1 cells, and participated in alveolar bone resorption in CKD model mice through ferroptosis.

Plant-derived natural medicines for the management of osteoporosis: A comprehensive review of clinical trials

Background

Osteoporosis is a chronic and systemic skeletal disease that is defined by low bone mineral density (BMD) along with an increase in bone fragility and susceptibility to fracture. This study aimed to overview clinical evidence on the use of herbal medicine for management of osteoporosis.

Methods

Electronic databases including Pubmed, Medline, Cochrane library, and Scopus were searched until November 2022 for any clinical studies on the efficacy and/or safety of plant-derived medicines in the management of osteoporosis.

Results

The search yielded 57 results: 19 on single herbs, 16 on multi-component herbal preparations, and 22 on plant-derived secondary metabolites. Risk of fracture, bone alkaline phosphatase, BMD, and specific bone biomarkers are investigated outcomes in these studies. Medicinal plants including Acanthopanax senticosus, Actaea racemosa, Allium cepa, Asparagus racemosus, Camellia sinensis, Cissus quadrangularis, Cornus mas, Nigella sativa, Olea europaea, Opuntia ficus-indica, Pinus pinaster, Trifolium pretense and phytochemicals including isoflavones, ginsenoside, Epimedium prenyl flavonoids, tocotrienols are among plant-derived medicines clinically investigated on osteoporosis. It seems that multi-component herbal preparations were more effective than single-component ones; because of the synergistic effects of their constituents. The investigated herbal medicines demonstrated their promising results in osteoporosis via targeting different pathways in bone metabolism, including balancing osteoblasts and osteoclasts, anti-inflammatory, immunomodulatory, antioxidant, and estrogen-like functions.

Conclusion

It seems that plant-derived medicines have beneficial effects on bone and may manage osteoporosis by affecting different targets and pathways involved in osteoporosis; However, Future studies are needed to confirm the effectiveness and safety of these preparations.

Modulation of Kv7 Channel Currents by Echinocystic Acid

Modulation of KCNQ-encoded voltage-gated potassium Kv7/M channel function represents an attractive strategy to treat neuronal excitability disorders such as epilepsy, pain, and depression. The Kv7 channel group includes five subfamily members (Kv7.1-Kv7.5). Pentacyclic triterpenes display extensive pharmacological activities including antitumor, anti-inflammatory, and antidepression effects. In this study, we investigated the effects of pentacyclic triterpenes on Kv7 channels. Our results show that echinocystic acid, ursonic acid, oleanonic acid, demethylzeylasteral, corosolic acid, betulinaldehyde, acetylursolic acid, and α-boswellic acid gradually exert decreasing degrees of Kv7.2/Kv7.3 channel current inhibition. Echinocystic acid was the most potent inhibitor, with a half-maximal inhibitory concentration (IC50) of 2.5 µM. It significantly shifted the voltage-dependent activation curve in a positive direction and slowed the time constant of activation for Kv7.2/Kv7.3 channel currents. Furthermore, echinocystic acid nonselectively inhibited Kv7.1-Kv7.5 channels. Taken together, our findings indicate that echinocystic acid is a novel and potent inhibitor that could be used as a tool to further understand the pharmacological functions of neuronal Kv7 channels. SIGNIFICANCE STATEMENT: Pentacyclic triterpenes reportedly have multiple potential therapeutic uses such as anticancer, anti-inflammatory, antioxidant, and antidepression effects. In the present study, we show that echinocystic acid, ursonic acid, oleanonic acid, and demethylzeylasteral inhibit Kv7.2/Kv7.3 channels to varying degrees. Of these, echinocystic acid was the most potent Kv7.2/Kv7.3 current inhibitor and inhibited Kv7.1-Kv7.5 currents in a nonselective manner.

Improving the generalizability of protein-ligand binding predictions with AI-Bind

Identifying novel drug-target interactions is a critical and rate-limiting step in drug discovery. While deep learning models have been proposed to accelerate the identification process, here we show that state-of-the-art models fail to generalize to novel (i.e., never-before-seen) structures. We unveil the mechanisms responsible for this shortcoming, demonstrating how models rely on shortcuts that leverage the topology of the protein-ligand bipartite network, rather than learning the node features. Here we introduce AI-Bind, a pipeline that combines network-based sampling strategies with unsupervised pre-training to improve binding predictions for novel proteins and ligands. We validate AI-Bind predictions via docking simulations and comparison with recent experimental evidence, and step up the process of interpreting machine learning prediction of protein-ligand binding by identifying potential active binding sites on the amino acid sequence. AI-Bind is a high-throughput approach to identify drug-target combinations with the potential of becoming a powerful tool in drug discovery.

Network pharmacology-based analysis of signaling pathways of an anti-osteoporotic triterpenoid from Acyranthes bidentata Blume root

In Korea folk remedies, Acyranthes bidentata Blume is a functional food plant to treat bone diseases; especially, its roots have been used to alleviate osteoporosis (OP), but its key chemical compound(s) and mechanism of action against osteoporosis have not reported yet. This study suggests that Acyranthes bidentata Blume root (ABBR) has promising compound(s) against OP. We utilized network pharmacology to evaluate the therapeutic value. The chemical compounds from Acyranthes bidentata Blume root (ABBR) were identified by gas chromatography-mass spectrum (GC-MS); their physicochemical properties have been evaluated by SwissADME. Next, the target(s) related to a triterpenoid or OP-related targets were investigated by public databases. The signaling pathways from final targets were visualized, constructed, and analyzed by RPackage. Finally, we performed a molecular docking (MD) to explore key target(s) and compound(s) by employing AutoDockVina tools; the residues of amino acids interacted with ligands were identified by LigPlot + v.22. A total of 24 chemicals were accepted by the Lipinski's rules. We found a sole triterpenoid from ABBR via GC-MS, suggesting that might be a potent ligand to alleviate OP. Thereby, the 42 targets were associated with the triterpenoid; the 19 targets among them were connected to OP-targets (1426). The final 19 targets were related directly to 8 signaling pathways on STRING database. On Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and a key signaling pathway (PPAR signaling pathway), four key targets (PPARA, PPARD, FABP3, and FABP4) and a key compound (Methyl 3β-hydroxyolean-18-en-28-oate) were selected via MD. Collectively, the triterpenoid from ABBR might have potent anti-osteoporotic efficacy by activating PPARA, PPARD, FABP3, and FABP4 on PPAR signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03362-5.

A Review on the Molecular Mechanisms of Action of Natural Products in Preventing Bone Diseases

The drugs used for treating bone diseases (BDs), at present, elicit hazardous side effects that include certain types of cancers and strokes, hence the ongoing quest for the discovery of alternatives with little or no side effects. Natural products (NPs), mainly of plant origin, have shown compelling promise in the treatments of BDs, with little or no side effects. However, the paucity in knowledge of the mechanisms behind their activities on bone remodeling has remained a hindrance to NPs’ adoption. This review discusses the pathological development of some BDs, the NP-targeted components, and the actions exerted on bone remodeling signaling pathways (e.g., Receptor Activator of Nuclear Factor κ B-ligand (RANKL)/monocyte/macrophage colony-stimulating factor (M-CSF)/osteoprotegerin (OPG), mitogen-activated protein kinase (MAPK)s/c-Jun N-terminal kinase (JNK)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), Kelch-like ECH-associated protein 1 (Keap-1)/nuclear factor erythroid 2–related factor 2 (Nrf2)/Heme Oxygenase-1 (HO-1), Bone Morphogenetic Protein 2 (BMP2)-Wnt/β-catenin, PhosphatidylInositol 3-Kinase (PI3K)/protein kinase B (Akt)/Glycogen Synthase Kinase 3 Beta (GSK3β), and other signaling pathways). Although majority of the studies on the osteoprotective properties of NPs against BDs were conducted ex vivo and mostly on animals, the use of NPs for treating human BDs and the prospects for future development remain promising.

Anti-inflammatory effects of Eclipta prostrata Linné on house dust mite-induced atopic dermatitis in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Atopic dermatitis (AD) is a kind of inflammation on the skin following with swollen, itchy, dryness and cracked skin. Though the exact cause of AD is unknown, there are evidence that people with AD have a compromised skin barrier along with inflammation. Eclipta prostrata Linné is a traditional herbal medicinal plant, has been used for the diabetes, obesity, jaundice, and inflammation. We supposed E. prostrata L. has an anti-inflammatory effect on the skin.

AIM OF THE STUDY

We aimed to assess the effect of E. prostrata L. EtOH extract (EP) and elucidate the associated molecular mechanisms.

MATERIALS AND METHODS

The effect of EP and the molecular mechanisms were eluciated in house dust mite (HDM)-induced AD mice model and TNF-α/IFN-γ-stimulated HaCaT keratinocytes by histological analysis, enzyme-linked immunosorbent assay, quantitative real time polymerase chain reaction, and Western blot.

RESULTS

The results revealed that EP improved the progression of AD symptoms, decreasing epidermis/dermis thickness, infiltrated immune cells, and restored the skin barrier dysfunction and imbalanced immune response. EP suppressed the expressions of T helper (Th)1, Th2, Th17 cytokines, phosphorylation of extracellular signal-regulated kinase/signal transducer and activator of transcription 1 in skin of HDM-induced AD mice as well as inhibition the translocation of nuclear factor-κB in HaCaT keratinocytes.

CONCLUSIONS

Collectively, EP improved the allergic inflammation of the skin through recovery the skin barrier, and regulation the immune balance. These results suggest EP may have therapeutic potential as an anti-atopic agent.

Eclipta prostrata (L.) L. (Asteraceae): Ethnomedicinal Uses, Chemical Constituents, and Biological Activities

Eclipta prostrata (L.) L. (Syn.: Eclipta alba (L.) Hassak, Family: Asteraceae) is an important medicinal plant in the tropical and subtropical regions. It is widely used in treating various diseases of skin, liver and stomach in India, Nepal, Bangladesh, and other countries. The main aim of this review was to collect and analyze the available information on traditional uses, phytoconstituents, and biological activities of E. prostrata. The scientific information was collected from the online bibliographic databases such as Scopus, MEDLINE/PubMed, Google Scholar, SciFinder, etc. and books and proceedings. The active phytochemicals were coumestan derivatives, phenolic acid derivatives, flavonoids, triterpenoid and steroid saponins, substituted thiophenes, etc. Various extracts and isolated compounds of E. prostrata showed a wide range of biological activities such as antimicrobial, anticancer, hepatoprotective, neuroprotective and hair growth promoting activities. Relatively a few studies have been performed to reveal the exact phytoconstituents responsible for their corresponding pharmacological activities. Future studies should focus on detailed mechanism based studies using animal models and clinical studies.

Combined Extract of Leonurus japonicus Houtt, Eclipta prostrata L., and Pueraria lobata Ohwi Improved Hot Flashes and Depression in an Ovariectomized Rat Model of Menopause

Menopause leads to ovarian hormone loss, which causes symptoms such as weight gain, hot flashes, and depression. Exploring nutraceuticals is important for treating menopausal symptoms that extensively impact women's quality of life. We hypothesized that a combination of Leonurus japonicus Houtt, Eclipta prostrata L., and Pueraria lobata Ohwi (LEPE) would alleviate menopausal symptoms in an ovariectomized menopausal rat model. Bilateral ovariectomy was performed and animals were assigned to five groups: (1) Sham, (2) Vehicle, (-) Control, (3) LEPE (100 mg/kg bw), (4) LEPE (200 mg/kg bw), and (5) Estradiol (3 μg/kg bw). LEPE was orally administered daily for 12 weeks. LEPE supplementation did not affect growth performance (body weight and feed intake) or body composition (lean mass and fat in tissue). LEPE did not cause deviations in aspartate aminotransferase, alanine aminotransferase, estradiol, and follicle-stimulating hormone levels, indicating no hepatotoxicity or endocrine disturbance. LEPE decreased type I collagen (CTX-1) but did not affect bone mineral density or osteocalcin. LEPE decreased tail temperature and increased rectal temperature, improving menopause-related vasomotor symptoms. Furthermore, LEPE ameliorated depression-related behavior, including in forced swimming and tail suspension tests. Thus, LEPE may improve menopausal symptoms by enhancing vasomotor symptoms and depression in an ovariectomized rat menopause model.

The Beneficial Effect of Boswellic Acid on Bone Metabolism and Possible Mechanisms of Action in Experimental Osteoporosis

Estrogen is instrumental in the pathological process of osteoporosis because a deficiency of this hormone increases the release of bone-resorbing cytokines. Acetyl-11-keto-β-boswellic acid (AKBA), a constituent from Boswellia serrata, has an anti-inflammatory effect by inhibiting tumor necrosis factor-α (TNF-α) expression, which leads to a decline in receptor activator of nuclear factor-kappa B (NF-κB) ligand, and consequently, a reduction in osteoclast activity. Hence, AKBA may be beneficial against bone loss during osteoporosis. Therefore, the current study intended to evaluate the beneficial effects of AKBA in ovariectomy-induced osteoporosis and to investigate its mechanism of action. Sham-operation or ovariectomy female Sprague Dawley rats were used for evaluating the antiosteoporotic effect of AKBA in this study. AKBA (35 mg/kg, p.o.) and estradiol (0.05 mg/kg, i.m.) were administered for 42 days. At the end of the experiment, body and uterus weights, serum and urine calcium and phosphorus, serum alkaline phosphatase, and urinary creatinine levels, besides serum levels of NF-κB and TNF-α were determined. Weight, length, thickness, hardness, calcium content, as well as the bone mineral density of femur bone and lumbar vertebra were measured. A histopathological examination was also carried out. AKBA ameliorated all tested parameters and restored a normal histological structure. Thus, AKBA showed good antiosteoporotic activity, which may be mediated through its suppression of the NF-κB-induced TNF-α signaling pathway.

Are Oxidative Stress and Inflammation Mediators of Bone Loss Due to Estrogen Deficiency? A Review of Current Evidence

Osteoporosis is one of the major health issues associated with menopause-related estrogen deficiency. Various reports suggest that the hormonal changes related to menopausal transition may lead to the derangement of redox homeostasis and ultimately oxidative stress. Estrogen deficiency and oxidative stress may enhance the expression of genes involved in inflammation. All these factors may contribute, in synergy, to the development of postmenopausal osteoporosis. Previous studies suggest that estrogen may act as an antioxidant to protect the bone against oxidative stress, and as an antiinflammatory agent in suppressing pro-inflammatory and pro-osteoclastic cytokines. Thus, the focus of the current review is to examine the relationship between estrogen deficiency, oxidative stress and inflammation, and the impacts of these phenomena on skeletal health in postmenopausal women.

A review on traditional uses, phytochemistry and pharmacology of Eclipta prostrata (L.) L

ETHNOPHARMACOLOGICAL RELEVANCE

Eclipta prostrata, a traditional herbal medicine, has long been used in Asia and South America for the therapy of hemorrhagic diseases (e.g. hemoptysis, hematemesis, hematuria, epistaxis and uterine bleeding), skin diseases, respiratory disorders, coronary heart disease, hair loss, vitiligo, snake bite and those caused by the deficiency of liver and kidney.

AIM OF THE REVIEW

In this review, we highlight relatively comprehensive and up-to-date information of E. prostrata on traditional uses, phytochemistry, pharmacology and toxicity, along with featuring the gaps in current knowledge, aiming to provide references for future research and possible opportunities for well applications of this medicinal plant.

MATERIALS AND METHODS

Information on E. prostrata was gathered from scientific databases (Google Scholar, Web of Science, Scifinder, Baidu Scholar, PubMed and CNKI). Information was also obtained from local books, Ph.D. theses and M.Sc. dissertations and Chinese Pharmacopoeia. The plant taxonomy was validated by the database "The Plant List".

RESULTS

Various phytochemical classes has been identified and isolated from the plant covering triterpenes, flavonoids, thiopenes, coumestans, steroids and others. Among these, coumestans are reported as the most common ingredients. The isolated crude extracts and individual compounds have been reported to exhibit promising pharmacological properties, such as hepatoprotective, osteoprotective, cytotoxic, hypoglycaemic, anti-inflammatory, anti-microbial, hypolipidemic, promoting hair growth, rejuvenative and neuroprotective effects.

CONCLUSIONS

Until now, significant progress has been witnessed in phytochemistry and pharmacology of E. prostrata. Thus, some traditional uses has been well supported and clarified by modern pharmacological studies. Moreover, E. prostrata also showed therapeutic potential in some refractory diseases such as cancer, dementia and diabetes. But, present findings are still insufficient that cannot satisfactorily explain some mechanisms of action. More well-designed studies in vitro especially in vivo are required to establish links between the traditional uses and bioactivities, discover new skeletons and activity molecules, as well as ensure safety before clinical use.

A polysaccharide from Eclipta prostrata alleviates experimental autoimmune encephalomyelitis through inhibiting Th17 cells

Eclipta prostrata has long been used as a medicinal herb in China. EAP20-1, a homogeneous polysaccharide with anti-complementary activity had been obtained from E. prostrate by using anion-exchange and size-exclusion chromatography. In this study, we found that EAP20-1 could inhibit in vitro lymphocyte proliferation stimulated by concanavalin-A or anti-CD3/anti-CD28 antibodies. Furthermore, in experimental autoimmune encephalomyelitis (EAE) mice, EAP20-1 treatment relieved the clinical symptoms, accompanied by reduced neuroinflammation and demyelination in spinal cords. Mechanistically, EAP20-1 reduced the mRNA expression of interleukin (IL)-17, IL-22, and RAR-related orphan receptor gamma t (RORγt) in the spleen; inhibited auto-reactive T cell proliferation and decreased the percentage of Th17 cells in response to myelin oligodendrocyte glycoprotein (MOG35-55) ex vivo. Moreover, EAP20-1 directly inhibited naïve CD4 + T cells differentiate into Th17 cells in vitro. These results indicating EAP20-1 could benefit EAE through inhibiting Th17 cell differentiation and suggesting a therapeutic potential of EAP20-1 in MS.

The Antiosteoporosis Effects of Zhuanggu Guanjie Pill In Vitro and In Vivo

We investigated the beneficial effects and underlying mechanisms of Zhuanggu Guanjie (ZGGJ) pill in osteoporosis in vitro and in vivo. Bone marrow macrophages from 4–6-week-old mice were cultured in the presence of macrophage colony-stimulating factor (15 ng/mL) and receptor activator of nuclear factor-κB ligand (30 ng/mL). Osteoclast differentiation was determined by quantification of tartrate-resistant acid phosphatase activity. Gelatin zymography was used to detect the activity of matrix metalloproteinases in osteoclasts. Ovariectomized rats were administered orally with estradiol valerate or ZGGJ for 8 weeks. Blood was collected to measure serum indices. Tibiae were harvested to carry out bone microcomputed tomography scanning, histomorphological analysis, and bone strength determination. ZGGJ inhibited tartrate-resistant acid phosphatase activity, matrix metalloproteinase 9 expression, and bone resorption in vitro. At doses of 0.55, 1.1, and 2.2 g/kg, ZGGJ exerted significant osteoprotective effects including inhibition of bone turnover markers and improved tibia bone strength in ovariectomized rats. Microcomputed tomographic analysis showed that ZGGJ improved the trabecular architecture with increased connectivity density and trabecular thickness and decreased trabecular spacing. These results revealed that ZGGJ prevents bone loss induced by ovariectomy in rats and that inhibition of bone resorption is involved in the bone-protective effects of ZGGJ.

Validated UPLC-MS/MS method for quantification of seven compounds in rat plasma and tissues: Application to pharmacokinetic and tissue distribution studies in rats after oral administration of extract of Eclipta prostrata L

A rapid, sensitive and specific ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed to investigate the pharmacokinetics and tissue distribution of Eclipta prostrata extract. Rats were orally administrated the 70% ethanol extract of E. prostrata, and their plasma as well as various organs were collected. The concentrations of seven main compounds, ecliptasaponin IV, ecliptasaponin A, apigenin, 3'-hydroxybiochanin A, luteolin, luteolin-7-O-glucoside and wedelolactone, were quantified by UPLC-MS/MS through multiple reactions monitoring method. The precisions (RSD) of the analytes were all <15.00%. The extraction recoveries ranged from 74.65 to 107.45% with RSD ≤ 15.36%. The matrix effects ranged from 78.00 to 118.06% with RSD ≤ 15.04%. To conclude, the present pharmacokinetic and tissue distribution studies provided useful information for the clinical usage of Eclipta prostrata L.

New insights into the tonifying kidney-yin herbs and formulas for the treatment of osteoporosis

Osteoporosis is characterized by an increasing osseous fragility and fracture resulting from the low mass and deteriorated microarchitecture in the bone tissue. The hormone replacement therapy and alendronate were frequently used to treat osteoporosis as the primary therapeutic strategy, but their adverse effects have severely limited their extensive clinical application, therefore, it is urgent to develop alternative or complementary therapeutic agents for anti-osteoporosis. Interestingly, with more people focusing on the complementary and alternative medicine, traditional Chinese herbs and formulas are being gradually recognized as safe and effective agents in the treatment of osteoporosis. In particular, a notable trend is that increasing studies are making efforts to clarify the anti-osteoporotic effects and mechanism of the tonifying kidney-yin herbs and formulas, a category of agents identified as effective therapy. Therefore, the purpose of this study is to comprehensively review the tonifying kidney-yin herbs and formulas that have been reported in the treatment of osteoporosis as well as how the agents play their roles in detail. This current study not only will advance our understanding of the actions of tonifying kidney-yin herbs and formulas, but also provide new evidence for the clinic use of the tonifying kidney-yin herbs and formulas in the treatment of osteoporosis.

Echinocystic acid ameliorates hyperhomocysteinemia-induced vascular endothelial cell injury through regulating NF-κB and CYP1A1

The present study investigated the role of echinocystic acid (EA) on the expression of nuclear factor (NF)-κB and cytochrome P450 1A1 (CYP1A1), and aortic morphology, in a rat model of hyperhomocysteinemia (Hhcy). A total of 50 Sprague Dawley rats were randomly divided into five groups as follows: Normal control (NC), model control (MC), vitamin control (VC; folic acid 1 mg/kg + vitamin B2 2 mg/kg + vitamin B12 10u g/kg), EA1 (20 mg/kg EA) and EA2 (40 mg/kg EA). Plasma homocysteine (Hcy) levels were determined via high performance liquid chromatography, and the morphology of the aorta was investigated using hematoxylin and eosin staining. Furthermore, aortic mRNA and protein levels of NF-κB and CYP1A1 were measured using reverse transcription-quantitative polymerase chain reaction analysis and western blotting, respectively. Plasma Hcy levels, and aortic mRNA and protein levels of NF-κB and CYP1A1, were significantly lower in the EA-treated group compared with the MC group (all P<0.05). However, the aortic morphology remained normal, including the endothelial cells of the inner layer, and smooth muscle cells of the media layer and adventitia. In conclusion, the results of the present study indicate that EA has a protective role on vascular endothelial cells in Hhcy through decreasing plasma Hcy, and thus NF-κB and CYP1A1 expression.

Echinocystic acid inhibits RANKL-induced osteoclastogenesis by regulating NF-κB and ERK signaling pathways

Receptor activator of nuclear factor-κB ligand (RANKL) is a key factor in the differentiation and activation of osteoclasts. Echinocystic acid (EA), a pentacyclic triterpene isolated from the fruits of Gleditsia sinensis Lam, was reported to prevent reduction of bone mass and strength and improve the cancellous bone structure and biochemical properties in ovariectomy rats. However, the molecular mechanism of EA on the osteoclast formation has not been reported. The purpose of this study was to investigate the effects and mechanism of EA on RANKL-induced osteoclastogenesis. Our results showed that EA inhibited the formation of osteoclast, as well as the expression of osteoclastogenesis-related marker proteins in bone marrow macrophages (BMMs). At molecular levels, EA inhibited RANKL-induced NF-κB activation and ERK phosphorylation in BMMs. In conclusion, the present study demonstrated that EA can suppress osteoclastogenesis in vitro. Moreover, we clarified that these inhibitory effects of EA occur through suppression of NF-κB and ERK activation. Therefore, EA may be a potential agent in the treatment of osteoclast-related diseases such as osteoporosis.

Natural Products from Chinese Medicines with Potential Benefits to Bone Health

Osteoporosis is a progressive, systemic bone disorder characterized by loss of bone mass and microstructure, leading to reduced bone strength and increased risk of fracture. It is often associated with reduced quality of life and other medical complications. The disease is common in the aging population, particularly among postmenopausal women and patients who receive long-term steroidal therapy. Given the rapid growth of the aging population, increasing life expectancy, the prevalence of bone loss, and financial burden to the healthcare system and individuals, demand for new therapeutic agents and nutritional supplements for the management and promotion of bone health is pressing. With the advent of global interest in complementary and alternative medicine and natural products, Chinese medicine serves as a viable source to offer benefits for the improvement and maintenance of bone health. This review summarizes the scientific information obtained from recent literatures on the chemical ingredients of Chinese medicinal plants that have been reported to possess osteoprotective and related properties in cell-based and/or animal models. Some of these natural products (or their derivatives) may become promising leads for development into dietary supplements or therapeutic drugs.