9-Demethoxy-medicarpin promotes peak bone mass achievement and has bone conserving effect in ovariectomized mice: Positively regulates osteoblast functions and suppresses osteoclastogenesis

Design, synthesis and biological evaluation of novel pyrimidine derivatives as bone anabolic agents promoting osteogenesis via the BMP2/SMAD1 signaling pathway

Anti-resorptive inhibitors such as bisphosphonates are widely used but they have limited efficacy and serious side effects. Though subcutaneous injection of teriparatide [PTH (1-34)] is an effective anabolic therapy, long-term repeated subcutaneous administration is not recommended. Henceforth, orally bio-available small-molecule-based novel therapeutics are unmet medical needs to improve the treatment. In this study, we designed, synthesized, and carried out a biological evaluation of 31 pyrimidine derivatives as potent bone anabolic agents. A series of in vitro experiments confirmed N-(5-bromo-4-(4-bromophenyl)-6-(2,4,5-trimethoxyphenyl)pyrimidin-2-yl)hexanamide (18a) as the most efficacious anabolic agent at 1 pM. It promoted osteogenesis by upregulating the expression of osteogenic genes (RUNX2 and type 1 col) via activation of the BMP2/SMAD1 signaling pathway. In vitro osteogenic potential was further validated using an in vivo fracture defect model where compound 18a promoted the bone formation rate at 5 mg kg-1. We also established the structure-activity relationship and pharmacokinetic studies of 18a.

9-Demethoxy-medicarpin: A potential bone health supplement for the management of protein deficiency-induced bone loss in growing rats

Human skeleton requires an adequate supply of many different nutritional factors for optimal growth and development. The role of nutrition in bone growth has piqued interest in recent years, especially in relation to maximizing peak bone mass and reducing the risk of osteoporosis. Protein deficiency-induced bone loss was induced in female growing rats. All experimental rodent diets were prepared as per recommendations for growing animals. 9-Demethoxy-medicarpin (DMM) treatment was given to growing Sprague Dawley (SD) rats at 1 mg and 10 mg dose orally for 30 days. Bones were collected for bone mineral density (BMD). Bone marrow cells were isolated from femur for calcium nodule formation. Serum samples were collected for biochemical parameters. We found that DMM treatment speeds up the recovery of musculoskeletal weakness by replenishing nutrients in proven rodent model. DMM supplementation for four weeks showed significantly increased vertebral, femur and tibial BMD compared with the untreated PD group. Albumin levels were significantly enhanced in treatment groups, in which 10 mg dose imparted a better effect. We conclude that DMM treatment led to increased BMD and biochemical parameters in protein deficient condition in growing rats and has potential as a bone growth supplement.

Homotherapy for heteropathy active components and mechanisms of Qiang-Huo-Sheng-Shi decoction for treatment of rheumatoid arthritis and osteoarthritis

Qiang-Huo-Sheng-Shi decoction (QHSSD), a classic traditional Chinese herbal formula, which has been reported to be effective in rheumatoid arthritis (RA) and osteoarthritis (OA). However, the concurrent targeting mechanism of how the aforementioned formula is valid in the two distinct diseases OA and RA, which represents the homotherapy-for-heteropathy principle in traditional Chinese medicine (TCM), have not yet been clarified. In the present study, network pharmacology was adopted to analyze the potential molecular mechanism, and therapeutic effective components of QHSSD on both OA and RA. A total of 153 active ingredients in QHSSD were identified, 142 of which associated with 59 potential targets for the two diseases were identified. By constructing the protein-protein interaction network and the compound-target-disease network, 72 compounds and 10 proteins were obtained as the hub targets of QHSSD against OA and RA. The hub genes of ESR1, PTGS2, PPARG, IL1B, TNF, MMP2, IL6, CYP3A4, MAPK8, and ALB were mainly involved in osteoclast differentiation, the NF-κB and TNF signaling pathways. Moreover, molecular docking results showed that the screened active compounds had a high affinity for the hub genes. This study provides new insight into the molecular mechanisms behind how QHSSD presents homotherapy-for-heteropathy therapeutic efficacy in both OA and RA. For the first time, a two-disease model was linked with a TCM formula using network pharmacology to identify the key active components and understand the common mechanisms of its multi-pathway regulation. This study will inspire more innovative and important studies on the modern research of TCM formulas.

Total flavonoid extract of Epimedium herb increases the peak bone mass of young rats involving enhanced activation of the AC10/cAMP/PKA/CREB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Epimedium sagittatum brevicornum Maxim. is an important traditional Chinese herb that has long been used to promote bone fracture healing and treat osteoporosis.

AIM OF THE STUDY

Achieving peak bone mass by adolescence has now been accepted to be fundamental for preventing osteoporosis in adulthood life. This study investigated the possibility of increasing peak bone mass in young rats using the total flavonoid extract of Epimedium herb (TFE).

MATERIALS AND METHODS

TFE was intragastrically administered to one-month-old Wistar rats at a low (100 mg/kg), middle (200 mg/kg) or high dose (400 mg/kg). Whole body bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry every two weeks. When BMD of any one of TFE groups was found to be significantly higher than that of the control, all rats were sacrificed, serum samples were collected for bone turnover biochemical assays, and femurs, tibiae and vertebrae were isolated and used in BMD, mechanical, micro-structural, histomorphometric and mechanistic studies.

RESULTS

Administration of TFE at middle and high doses for two months significantly increased the whole body, femoral and vertebral BMDs, and improved the bone mechanical and micro-architectural properties. The serum turnover biochemical results and the enhanced expression levels of bone-formation regulatory genes (Runx-2, OSX, and BMP-2) demonstrated that TFE administration increased bone formation but had no effect on bone resorption. The increased phosphorylation levels in femurs of PKA and CREB and expression of AC10 (the only soluble form of adenylyl cyclase) and the increased serum cAMP level after 4 h of TFE administration indicated that TFE promoted bone formation by activating the AC10/cAMP/PKA/CREB pathway in vivo.

CONCLUSIONS

Oral administration of TFE at 200 mg/kg for two months can increase the peak bone mass of growing rats, suggesting the possibility of using total flavonoid extract of Epimedium herb to increase the peak bone mass in adolescence which is important for preventing osteoporosis in adult life.

3-Piperidylethoxypterocarpan: A potential bone anabolic agent that improves bone quality and restores trabecular micro-architecture in ovariectomized osteopenic rats

A series of new 6H-benzofuro[3, 2-c]chromenes (BFC, pterocarpans) with structure-activity relationships were investigated for their potential use in osteoporosis treatment. One of the BFCs 3-piperidylethoxypterocarpan 20 promotes osteoblast differentiation and mineralization at a dose as low as 1 pM via activation of ER/P38MAPK/BMP-2 pathway. When evaluated for in-vivo osteogenic activity in female Sprague-Dawley rats, BFC 20 increased bone mineral density and new bone formation, compared with control at 1.0 and 10.0 mg/kg/body weight by oral gavage for 30 days. The compound was devoid of any uterotrophic effect and led to the new bone formation in adult ovariectomized osteopenic rats. BFC 20 compound also inhibited bone resorption by reducing Ovx induced increase in urinary CTx, thus exhibiting both bone anabolic and anti-catabolic action. Finally, BFC 20 treatment to Ovx rats led to improved trabecular microarchitectural restoration and exhibited therapeutic potential as a dual acting anti-osteoporotic agent for the management of osteoporosis.

Pterocarpan scaffold: A natural lead molecule with diverse pharmacological properties

Phytoalexins are substances produced by plants that act as potent inhibitors of pathogens. Pterocarpans are biologically active isoflavonoids most commonly found in the family Fabaceae that have the ability to act as phytoalexins. It is made up of a tetracyclic ring system possessing benzofuran-benzopyran. A very great number of pterocarpans have been isolated from natural sources and they are proved to have significant biological activities such as anti-microbial, anti-cancerous, anti-inflammatory and anti-malarial activities. Recently, pterocarpans gained lot of attention because of the broad range of anti-cancer activities in various cancer cell lines such as breast, leukemia, cervical, lung, colon and melanoma. Interestingly, pterocarpans exhibited inhibitory potency against many enzymes such as PTP1B, Neuraminidase, and α-glycosidase. In addition, they were shown to have anti-estrogenic and anti-diabetic activities. This review is a comprehensive inventory of the structures and sources of pterocarpans and it emphasizes on the biological evaluations of pterocarpans from various plant sources and their scope as a lead molecule.