Effect of Buguzhi (Psoralea corylifolia fruit) extract on bone formation

Bushen huoxue decoction inhibits RANKL-stimulated osteoclastogenesis and glucocorticoid-induced bone loss by modulating the NF-κB, ERK, and JNK signaling pathways

Glucocorticoid-induced osteoporosis (GIOP) is the most common form of secondary osteoporosis, which is caused by a disorder in bone metabolism due to excessive activation of osteoclasts. Bushen Huoxue decoction (BHD) is an herbal formula with multiple pharmacological effects, including anti-inflammatory, antioxidant activity and stem cell migration promotion. However, the effect of BHD on osteoclastogenesis has not been reported. In this study, we aimed to elucidate the effect of BHD on RANKL-stimulated osteoclastogenesis and explored its underlying mechanisms of action in vitro. Our results show that BHD had no effect on BMMs and RAW264.7 cells viability, but inhibited RANKL-induced osteoclast formation in vitro. Furthermore, BHD attenuated RANKL-induced NF-κB, ERK, and JNK signaling. The attenuation of NF-κB, ERK, and JNK activation were enough to impede downstream expression of c-fos and NFATc1 and related specific genes. Meanwhile, we investigated the therapeutic effect of BHD on glucocorticoid-induced osteoporosis (GIOP) mice. The result indicated that BHD prevents glucocorticoid-induced osteoporosis and preserves bone volume by repressing osteoclast activity. Collectively, BHD shows significant osteoclast inhibition and holds great promise in the treatment of osteoporosis.

The efficacy and safety of Xianling Gubao capsules in the treatment of knee osteoarthritis: A protocol for a randomized, double-blind, controlled trial

BACKGROUND

Knee osteoarthritis (KOA) is a chronic degenerative joint disease, which is the most common type of osteoarthritis. The clinical manifestations are pain, swelling, and dysfunction of the knee joint, which seriously reduces the quality of life of patients and causes a huge social burden. At present, western medicine mainly focuses on symptomatic treatment, such as anti-inflammatory and pain relief, joint cavity injection, joint replacement, etc. The curative effect has certain limitations. Xianling Gubao capsule has some advantages in the treatment of KOA, but it lacks high-quality clinical research to verify it. Therefore, the purpose of this study is to evaluate the efficacy and safety of Xianling Gubao capsule in the treatment of KOA.

METHODS

A randomized, double-blind, double-simulation, parallel controlled trial design was used to study the efficacy and safety of Xianling Gubao capsules in the treatment of KOA. The patients were randomly divided into a treatment group and the control group according to 1:1. The treatment group: Xianling Gubao capsule + glucosamine hydrochloride capsule simulation agent treatment; the control group: glucosamine hydrochloride capsule + Xianling Gubao capsule simulation agent treatment. Both groups received standard treatment for 8 weeks and followed up for 30 days. And at the same time, pay attention to its efficacy and safety indicators. Observation indicators include: the western Ontario and McMaster universities osteoarthritis index, hospital for special surgery knee score, liver and kidney function, adverse reactions, etc. Data analysis was performed using SPSS 25.0 software.

DISCUSSION

This study will evaluate the efficacy and safety of Xianling Gubao capsule in the treatment of KOA. The results of this experiment will provide evidence support for Xianling Gubao capsule in the treatment of KOA.

TRIAL REGISTRATION

OSF Registration number: DOI 10.17605/OSF.IO/ERM9C.

Neobavaisoflavone inhibits osteoclastogenesis through blocking RANKL signalling-mediated TRAF6 and c-Src recruitment and NF-κB, MAPK and Akt pathways

Psoralea corylifolia (P corylifolia) has been popularly applied in traditional Chinese medicine decoction for treating osteoporosis and promoting fracture healing since centuries ago. However, the bioactive natural components remain unknown. In this study, applying comprehensive two-dimensional cell membrane chromatographic/C18 column/time-of-flight mass spectrometry (2D CMC/C18 column/TOFMS) system, neobavaisoflavone (NBIF), for the first time, was identified for the bioaffinity with RAW 264.7 cells membranes from the extracts of P corylifolia. Here, we revealed that NBIF inhibited RANKL-mediated osteoclastogenesis in bone marrow monocytes (BMMCs) and RAW264.7 cells dose dependently at the early stage. Moreover, NBIF inhibited osteoclasts function demonstrated by actin ring formation assay and pit-formation assay. With regard to the underlying molecular mechanism, co-immunoprecipitation showed that both the interactions of RANK with TRAF6 and with c-Src were disrupted. In addition, NBIF inhibited the phosphorylation of P50, P65, IκB in NF-κB pathway, ERK, JNK, P38 in MAPKs pathway, AKT in Akt pathway, accompanied with a blockade of calcium oscillation and inactivation of nuclear translocation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1). In vivo, NBIF inhibited osteoclastogenesis, promoted osteogenesis and ameliorated bone loss in ovariectomized mice. In summary, P corylifolia-derived NBIF inhibited RANKL-mediated osteoclastogenesis by suppressing the recruitment of TRAF6 and c-Src to RANK, inactivating NF-κB, MAPKs, and Akt signalling pathways and inhibiting calcium oscillation and NFATc1 translocation. NBIF might serve as a promising candidate for the treatment of osteoclast-associated osteopenic diseases.

Surface area expansion by flower-like nanoscale layered double hydroxides for high efficient stir bar sorptive extraction

Enhancing the surface area of stationary phase is essential in chromatographic science. In this work, nanoscale NiAl-layered double hydroxides (NiAl-LDHs) with flower-like structure was used as a platform for supporting the stationary phase. Then strong hydrophobic p-naphtholbenzein molecule was immobilized onto the LDHs layer as sorbent for stir bar sorptive extraction (SBSE). The flower-like LDHs layer significantly increased the extraction efficiency through increasing the specific surface area and immobilized amounts of stationary phase. In addition, the LDHs can also provide anion exchange ability, which expanded the application of this stir bar for analysis of not only hydrophobic but also anionic analytes. For improving the workability, a poly(ether ether ketone) (PEEK) jacket stir bar with detachable dumbbell-shaped structure was employed. The PEEK jacket with high mechanical strength and dumbbell-shaped structure improved the durability of stir bar and the detectable design allowed elution to be realized with less solvent that enhanced the enrichment factor. The proposed stir bar showed good performance for the extraction of multiple analytes including flavonoids, non-steroid anti-inflammatory drugs and chlorophenoxy acids. By coupling with high performance liquid chromatography-ultraviolet detection (HPLC-UV), the SBSE-HPLC-UV method was applied for the extraction of three active components including bavachin, isobavachalcone and bavachinin in Psoralea corylifolia L. herb with low limit detection of 0.01-0.02 ng/mL.

A Network Pharmacology Approach for Uncovering the Osteogenic Mechanisms of Psoralea corylifolia Linn

Background and Aim

Psoralea corylifolia Linn (PCL) is an herb that is commonly used for alleviating osteoporosis and vitiligo. Although accumulating evidence has demonstrated the antiosteoporotic effect of PCL, the identities of the osteogenic compounds in PCL and their functional targets remain elusive. To investigate the osteogenic ingredients in PCL and their functional mechanisms, network pharmacology analysis was performed on the targets of PCL and osteogenesis.

Methods

The active components of PCL were screened by literature review. The potential protein targets of the active PCL components were predicted with the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Search Tool for Interactions of Chemicals (STITCH), SwissTargetPrediction, and PubChem. The target networks related to PCL and osteogenic differentiation were constructed by using Cytoscape. MC3T3-E1 cells were used to verify the targets.

Results

Twenty-three active components of PCL and 162 potential target proteins were identified. Further analysis reduced the number of potential target proteins to 71. Of the 23 components, bavachalcone, psoralen, bavachinin, neobavaisoflavone, methoxsalen, psoradin, bakuchiol, and angelicin may be the main active components of PCL that promote bone formation. PPARγ and aryl hydrocarbon receptor (AhR) were verified as targets of PCL in MC3T3-E1 cells, and the western blot and immunofluorescence staining results showed that compared to the control, PCL reduced the expression of these targets.

Conclusions

The active components of PCL and the mechanisms by which they promoted osteogenic differentiation were successfully identified using network pharmacology.

Genus Psoralea: A review of the traditional and modern uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Psoralea (Fabaceae) harbours 105 accepted species that are extensively used by local peoples and medicinal practitioners of China, India, and other countries for treatment of tooth decay, psoriasis, leucoderma, leprosy, kidney problems, tuberculosis, indigestion, constipation and impotence. Presently, pharmacological research reports are available on only few species namely Bituminaria bituminosa (Syn: P. bituminosa), P. canescens, P. corylifolia, P. esculenta, P. plicata and P. glandulosa which are valued for their chemical constituents and traditional uses.

AIM OF THE REVIEW

This review article provides explicit information on traditional uses, phytochemistry, and pharmacological activities of selected Psoralea species. The possible trends and perspectives for future research on these plants are also discussed.

MATERIALS AND METHODS

An extensive and systematic review of the extant literature was carried out, and the data under various sections were identified using a computerized bibliographic search via the PubMed, Web of Science and Google Scholar, CAB Abstracts, MEDLINE, EMBASE, INMEDPLAN, NATTS as well as several websites.

KEY FINDINGS

A total of 291 bioactive compounds from 06 species of genus Psoralea have been isolated and characterized. However, P. bituminosa alone possess nearly 150 compounds. These bioactive compounds belong to different chemical classes, including flavonoids, coumarins, furanocoumarins, chalcones, quinines, terpenoids and some others due to which these species exhibit significant anti-oxidant, anti-bacterial, anti-fungal, anti-viral, anti-helmintic, anti-diabetic, diuretic, hepatoprotective, anti-cancer and anti-tumor activities. P. corylifolia L. (Babchi), a Chinese traditional medicinal plant has been used in traditional medicine for many decades for its healing properties against numerous skin diseases such as leprosy, psoriasis and leucoderma.

CONCLUSIONS

The in vitro studies and in vivo models have provided a simple bio-scientific justification for various ethnopharmacological uses of Psoralea species. From the toxicological perspective, the root, leaf, and seed extracts and their preparations have been proven to be safe when consumed in the recommended doses. But, meticulous studies on the pharmaceutical standardization, mode of action of the active constituents, and sustainable conservation of Psoralea species are needed, to meet the growing demands of the pharmaceutical industries, and to fully exploit their preventive and therapeutic potentials.

The higher osteoprotective activity of psoralidin in vivo than coumestrol is attributed by its presence of an isopentenyl group and through activated PI3K/Akt axis

Prenylation of bioactive natural compounds has been postulated to be able to enhance the utilization rate and affinity of the compounds with cell membranes, thus promote their bioactivities. Coumestrol, isolated from Medicago sativa, has been known as a phytoestrogen which has bone health benefits. In our previous work, psoralidin, a prenylated coumestrol, was proved to have a higher ability than coumestrol to promote bone formation and to attenuate resorption in vitro. However, it remains to be investigated whether psoralidin will have stronger bone health benefits than coumestrol. In the current study, psoralidin was isolated from Psoralea corylifolia L. and the osteotropic activities of coumestrol and psoralidin were compared in ovariectomized (OVX) rats. Both coumestrol and psoralidin were found to suppress OVX-induced bone loss in vivo, as shown by improved total bone mineral content (t-BMC) or density (t-BMD) and mineral apposition rate, bone biomechanical properties, microstructure and trabecular bone formation, enhanced osteogenic differentiation but suppressed adipogenic differentiation of bone marrow stromal cells (BMSCs), and activation of PI3K/Akt axis and downstream factors such as GSK3β/β-catenin and Nrf-2/HO-1. However, psoralidin was shown to have higher activities than coumestrol in the above measurements/indices. Our findings demonstrate that psoralidin, as a novel anti-osteoporosis candidate, could suppress bone loss in OVX rats and have better osteoprotective effects than coumestrol, which may be related to the presence of the isopentenyl group in psoralidin.

Evaluation on Antimicrobial Activity of Psoraleae semen Extract Controlling the Growth of Gram-Positive Bacteria

This study investigated bacterial growth-inhibitory effect of 69 therapeutic herbal plants extracts on 9 bacterial strains using a disc diffusion assay. Especially, the antimicrobial activity of Psoraleae semen, which showed different activity on pathogenic Gram-positive and Gram-negative bacteria, was evaluated by MIC (minimal inhibition concentration) and biofilm formation assay. The effect of Psoraleae semen extract on bacterial cell membranes was examined by measurement of protein leakage (optical density at 280 nm) and scanning electron microscope (SEM). No clear zone was formed on discs containing Gram-negative bacteria, but Gram-positive bacteria exhibited clear zones. The MICs of Psoraleae semen extract were 8 μg/mL for Streptococcus mutans, and 16 μg/mL for Enterococci and Staphylococcus aureus. In addition, biofilm formation was inhibited at concentration 8-16 μg/mL. Protein leakage values and SEM images revealed that cell membranes of Gram-positive bacteria were impaired following exposure to the extract. Further, the extract inhibited the growth of Listeria monocytogenes in sausages. These results indicate that Psoraleae semen extract could be utilized as a natural antimicrobial agent against Gram-positive bacteria.

The Effect of Salt-Processed Psoralea corylifolia on Generative Organ Targeting

Psoralen and isopsoralen are two isomers and main effective components within Psoralea corylifolia. In order to investigate the salt-processing effect on tissue distribution characters of psoralen and isopsoralen, a sensitive and accurate ultrahigh pressure liquid chromatographic tandem mass spectrometric (UHPLC-MS/MS) method has been developed and validated for simultaneous determination of the 2 components in rats' tissues after administration of the extracts that came from either crude or salt-processed Psoralea corylifolia L. Data displayed that both areas under the curve (AUC) of psoralen and isopsoralen from salt-processed scurfpea fruit group were significantly increased compared with that of the crude herb group, especially in heart (p < 0.05), ovary, and testes (p < 0.001). Though the RE and RC_max of psoralen and isopsoralen in all of the investigated organs were over 1.0, generative organs kept the maximum value. The experiment manifested that salt-processing of scurfpea fruit can increase the distribution of psoralen and isopsoralen to generative organs, heart and spleen, and the distribution of psoralen and isopsoralen to generative organs is significantly higher compared to heart and spleen (p < 0.01). Results indicate that salt-processing of scurfpea fruit can significantly increase the distribution of psoralen and isopsoralen to generative organs.

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.

Positive skeletal effect of two ingredients of Psoralea corylifolia L. on estrogen deficiency-induced osteoporosis and the possible mechanisms of action

Estrogen replacement therapy (ERT) is utilized as a major regime for treatment of postmenopausal osteoporosis at present. However, long-term supplement of estrogen may cause uterine hyperplasia and hypertension leading to a high risk of endometrial cancer and breast cancer. Psoralea corylifolia L. has long been used as tonic and food additives in many countries. Previous studies had found two ingredients in P. corylifolia L.: bavachin and bakuchiol exhibited osteoblastic activity. The present study was designed to investigate the protective effect of bakuchiol and bavachin on ovariectomy-induced bone loss and explore the possible mechanism. In vivo, bakuchiol and bavachin could prevented estrogen deficiency-induced bone loss in ovariectomized rats without uterotrophic activity. In vitro studies suggested that bakuchiol and bavachin induced primary human osteoblast differentiation by up-regulating the Wnt signalling pathway. This study suggests that such a bone-protective role makes them a promising and safe estrogen supplement for the ERT.

In vivo screening for anti-osteoporotic fraction from extract of herbal formula Xianlinggubao in ovariectomized mice

Background and Objectives

Traditional Chinese Medicine (TCM) Fufang or formula Xianlinggubao (XLGB) is a prescribed TCM drug in China registered for prevention and treatment of osteoporosis. Fufang in TCM is comprised of a group of herbal compounds contributing in group to the treatment efficacy. The present study aims to identify the bioactive fraction(s) in XLGB extract that account(s) dominantly for its osteogenic effects.

Methods

The extract of XLGB formula was separated into three fractions using chromatography, i.e., XLGB-A, XLGB-B and XLGB-C. They were administrated to 4-month old ovariectomized (OVX) mice for 6 weeks to determine which bioactive fraction(s) were more effective for preventing OVX-induced bone loss evaluated by microCT, biomechanical testing and biochemical markers. The main peaks of the key fraction were identified using reference compounds isolated from the fraction. In addition, the effects of the composite compounds in XLGB-B on osteoblasts’ proliferation and mineralization were evaluated in UMR 106 cells.

Results

XLGB-B with a yield of 13.0% from herbal Fufang XLGB was identified as the most potential one among the three fractions for prevention of OVX-induced bone loss confirmed with bone mass, bone microarchitecture, bone strength and bone turnover markers. Nine compounds in HPLC fingerprint were identified in the XLGB-B fraction, including phenylpropanoids from Herba Epimedii, terpenes from Radix Dipsaci and coumarins from Fructus Psoraleae. In addition, the identified compounds effectively promoted proliferation and/or mineralization of osteoblast-like UMR 106 cells in vitro.

Conclusion

XLGB-B with defined phytochemical structures was screened as the key fraction that demonstrated preventive effects on OVX-induced bone loss in mice. The present study laid down a foundation towards a new generation of herbal Fufang characterized with “less herbal materials for achieving equal treatment efficacy” in development strategy of TCM for prevention of OVX-induced osteoporosis.

Identification of phenylpropanoids in fig (Ficus carica L.) leaves

In this study, the phenylpropanoid composition and antioxidant activity of identified components in fig (Ficus carica L.) leaves were examined. Known polyphenols rutin, isoschaftoside, isoquercetin, and chlorogenic acid were identified. Furthermore, caffeoylmalic acid (CMA) was the most abundant polyphenol and was identified for the first time. CMA exhibited antioxidant activity similar to that of vitamin C or catechin. Psoralen and bergapten were identified as known furanocoumarins, with psoralen being the most abundant. Moreover, psoralic acid glucoside (PAG) was identified for the first time. As a precursor of psoralen, PAG content was equivalent to the psoralen content in moles. Notably, the content of these compounds varied between the five fig varieties, and the furanocoumarin and PAG contents varied more than that of the polyphenols. Further investigations concerning the influence of CMA and PAG on human health are necessary to elucidate functionalities of fig leaves.

Delivery of small molecules for bone regenerative engineering: preclinical studies and potential clinical applications

Stimulation of bone regeneration using growth factors is a promising approach for musculoskeletal regenerative engineering. However, common limitations with protein growth factors, such as high manufacturing costs, protein instability, contamination issues, and unwanted immunogenic responses of the host reduce potential clinical applications. New strategies for bone regeneration that involve inexpensive and stable small molecules can obviate these problems and have a significant impact on the treatment of skeletal injury and diseases. Over the past decade, a large number of small molecules with the potential of regenerating skeletal tissue have been reported in the literature. Here, we review this literature, paying specific attention to the prospects for small molecule-based bone-regenerative engineering. We also review the preclinical study of small molecules associated with bone regeneration.

Growth sensitivity in the epiphyseal growth plate, liver and muscle of SD rats is significantly enhanced by treatment with a fermented soybean product (cheonggukjang) through stimulation of growth hormone secretion

Cheonggukjang (CKJ), a fermented soybean product, has been reported to have beneficial effects on various chronic diseases, including cardiovascular disease, cancer and immune diseases. To investigate whether CKJ induces growth sensitivity in mammals, alterations of key parameters related to their growth were analyzed. Sprague‑Dawley (SD) rats were treated with a high concentration of CKJ (H‑CKJ) or a low concentration of CKJ (L‑CKJ) for 10 days, and compared with vehicle-treated rats. The CKJ contained a high concentration of total flavonoids, phenolic compounds, daidzein and genistein, compared with the non-fermented soybean product. Body weight was higher in the H‑CKJ‑treated group compared with that in the vehicle‑ and L‑CKJ‑treated groups, whereas the weights of three organs (the brain, liver and kidney) were higher in the L‑CKJ‑treated group compared with the remaining two groups. However, no significant differences in femur length and weight were detected between the CKJ‑ and vehicle‑treated groups. The thickness of the epiphyseal growth plate in proximal femoral epiphysis was broadest in the H‑CKJ‑treated group compared with the vehicle- and L‑CKJ‑treated groups. Furthermore, the level of growth hormone (GH) was highest in the serum of the L‑CKJ‑treated group, although that of the H‑CKJ‑treated group was lower compared with that in the L‑CKJ group. Moreover, the expression levels of the GH receptor increased in the liver tissue, but not in the muscle tissue, of the L‑CKJ‑ and H‑CKJ‑treated groups. In the downstream signaling pathway of the GH receptor, the phosphorylation levels of Akt and Erk were differentially regulated between the liver and muscle. These results suggest that CKJ extract may enhance the sensitivity of the femur, liver and muscle epiphyseal growth plate in SD rats, through the upregulation of GH secretion.

Psoralen inhibits bone metastasis of breast cancer in mice

Breast cancer is the most common female malignancy and it frequently metastasizes to bone. Metastatic breast cancer continues to be the primary cause of death for women in East and Southeast Asia. Psoralen is a furocoumarin that can be isolated from the seeds of Psoralea corylifolia L. Psoralen exhibits a wide range of biological properties and has been demonstrated as an antioxidant, antidepressant, anticancer, antibacterial, and antiviral agent. Additionally, it is involved in the formation and regulation of bone. This study investigated whether psoralen can inhibit metastasis of breast cancer to bone in vivo. Histological, molecular biological, and imaging analyses revealed that psoralen inhibits bone metastases in mice. Psoralen may function to inhibit breast cancer cell growth in the bone microenvironment and regulate the function of osteoblasts and osteoclasts in tumor-bearing mice. The results of this study suggest that psoralen is a bone-modifying agent and a potential therapeutic to treat patients with bone metastases.

Separation, identification, and quantification of active constituents in Fructus Psoraleae by high-performance liquid chromatography with UV, ion trap mass spectrometry, and electrochemical detection

The qualitative and quantitative analysis of active constituents in Fructus Psoraleae is presented by high-performance liquid chromatography (HPLC) coupled with different detections. Extracts of Fructus Psoraleae were examined by HPLC with ion trap mass spectrometry (IT-MS) and 18 major compounds of coumarins, benzofuran glycosides, flavonoids, and meroterpene were identified. The determination of four major constituents including bavachin, isobavachalcone, bavachinin, and bakuchiol was accomplished by HPLC with UV, MS, and electrochemical detection (ECD). These methods were evaluated for a number of validation characteristics (repeatability, LOD, calibration range, and recovery). ECD obtained a high sensitivity for analysis of the four components; MS provided a high selectivity and sensitivity for determination of bavachin, isobavachalcone, and bavachinin in negative-ion mode. After optimization of the methods, separation, identification. and quantification of the four components in Fructus Psoraleae were comprehensively tested by HPLC with UV, MS, and ECD.

Psoralen stimulates osteoblast differentiation through activation of BMP signaling

Osteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. In order to improve the treatment of osteoporosis, identification of anabolic and orally available agents with minimal side effects is highly desirable. Psoralen is a coumarin-like derivative extracted from Chinese herbs, which have been used to treat bone diseases for thousands of years. However, the role of Psoralen in osteoblast function and the underlying molecular mechanisms remain poorly understood. In this study, we found that Psoralen promoted osteoblast differentiation in primary mouse calvarial osteoblasts in a dose-dependent manner, demonstrated by up-regulation of expressions of osteoblast-specific marker genes including type I collagen, osteocalcin and bone sialoprotein and enhancement of alkaline phosphatase activity. We further demonstrated that Psoralen up-regulated the expression of Bmp2 and Bmp4 genes, increased the protein level of phospho-Smad1/5/8, and activated BMP reporter (12xSBE-OC-Luc) activity in a dose-dependent manner, as well as enhanced the expression of Osx, the direct target gene of BMP signaling. Deletion of the Bmp2 and Bmp4 genes abolished the stimulatory effect of Psoralen on the expression of osteoblast marker genes, such as Col1, Alp, Oc and Bsp. Our results suggest that Psoralen acts through the activation of BMP signaling to promote osteoblast differentiation and demonstrate that Psoralen could be a potential anabolic agent to treat patients with bone loss-associated diseases such as osteoporosis.

Characterization of isoflavone synthase gene from Psoralea corylifolia: a medicinal plant

Isoflavones are known to possess medicinal properties and implicated in plant-pathogen interaction. We have for the first time isolated and functionally characterized an isoflavones synthase (IFS) gene from a traditionally acclaimed medicinal plant Psoralea corylifolia abundantly growing in tropical and subtropical regions. The IFS catalyzes the exclusive reaction of phenylpropanoid pathway in leguminous plants to produce isoflavones. The full-length cDNA (PcIFS) of the gene comprised 1,563 bp and putatively encodes a polypeptide of 520 amino acid residues. The gene is expressed ubiquitously although at varying levels in different parts of the plant. The expression analysis suggests that the gene is responsive to methyl jasmonate, salicylic acid and wounding. Overexpression of PcIFS in non-leguminous tobacco plant led to the accumulation of isoflavones in petal tissue, suggesting it a functional gene from P. corylifolia involved in isoflavones biosynthesis.