Extract and fraction from Ulmus wallichiana Planchon promote peak bone achievement and have a nonestrogenic osteoprotective effect

Catechin and flavonoid glycosides from the Ulmus genus: Exploring their nutritional pharmacology and therapeutic potential in osteoporosis and inflammatory conditions

This review investigates the therapeutic effects of Ulmus species extracts, traditionally used as tea ingredients in East Asia, on bone health and inflammatory conditions. Through the analysis of 9757 studies, narrowing down to 56 pertinent ones, we evaluated the safety and efficacy of Ulmus extracts. The focus was on catechin glycosides (CG) and flavonoid glycosides (FG), key compounds identified for their potential benefits. The research highlights the extracts' role in enhancing bone mineral density (BMD) by stimulating osteoblast activity and suppressing osteoclast differentiation, suggesting a protective effect against osteoporosis. Furthermore, the extracts demonstrated significant anti-inflammatory properties by modulating inflammatory markers and pathways. The findings confirm the historical use of Ulmus extracts in East Asia for health benefits and recommend further exploration into functional foods and nutraceuticals. The review calls for more rigorous research, including clinical trials, to establish optimal use and integration into modern health solutions. It underscores the potential of Ulmus extracts in promoting bone health and managing inflammation, advocating for a bridge between traditional practices and contemporary scientific validation. In conclusion, Ulmus extracts, a material long consumed as tea ingredients in East Asia, exhibit significant potential for improving bone health and reducing inflammation. This review calls for additional research to explore their full therapeutic capabilities, emphasizing the need for optimized extraction methods and clinical trials. It reinforces the importance of bridging traditional knowledge with contemporary scientific approaches to health and dietary solutions, promoting overall wellness.

Potential use of barks of woody vascular plants in bone mending: A review

The use of synthetic drugs to overcome bone ailments causes severe side effects, but the application of herbals is helpful in maintaining bone health and accelerating bone mending. Currently, there is no oral allopathic medicine to hasten bone healing, though folk and traditional practices have adopted herbal to fasten the recovery from bone ailments. Earliest recovery is a universally desired phenomenon, especially for elderly people where many more cases of traumatic injuries are common along the compromised body immunity. The computerized database search engines, such as Google Scholar, PubMed, ScienceDirect, Springer Link, etc., and textbooks were used to collect all relevant information about barks for bone mending activity published from 1990 onwards using certain keywords such as bark, folklore/ traditional bone healing practices, and phytopharmacology. The results obtained were compiled to make this review and related information is tabulated herewith. Traditional herbal bone healing exists in every society in the world. The plant barks of a few species (e.g., Ficus religiosa, Prunus cerasoides, Terminalia arjuna, etc.) have outstanding significance for bone healing because of their special chemical composition and novel properties to reduce swelling, pain, soreness, and speedy recovery of functions. Mostly bark extracts are rich in polyphenols, and minerals, represented with antioxidant, immunostimulatory, antibacterial properties, etc. There is a diversity of bark utilization for bone healing from different plant species, globally, of which only a few have been phytopharmacologically deciphered. Validated bark ingredients as medicine or food supplements are more useful due to the least side effects. Entrepreneurs have a scope to use bioactive obtained from plant barks that have not been scientifically screened till now. The research focused on the commercial application of plant barks as green medicine needs fingerprints of bioactive and clinically validated data including the concentration of biomarkers in the blood (IC50) for reducing the healing period. Phytopharmacological screening of barks used in folk medicine and synthesizing the therapeutics at mega quantities in industries is an array of hopes for sustainable utilization of natural resources. The bio-stimulating knowledge of certain herbal ingredients will be helpful in the development of synergistic formulations for rapid bone mending.

Promising Therapeutic Treatments for Cardiac Fibrosis: Herbal Plants and Their Extracts

Cardiac fibrosis is closely associated with multiple heart diseases, which are a prominent health issue in the global world. Neurohormones and cytokines play indispensable roles in cardiac fibrosis. Many signaling pathways participate in cardiac fibrosis as well. Cardiac fibrosis is due to impaired degradation of collagen and impaired fibroblast activation, and collagen accumulation results in increasing heart stiffness and inharmonious activity, leading to structure alterations and finally cardiac function decline. Herbal plants have been applied in traditional medicines for thousands of years. Because of their naturality, they have attracted much attention for use in resisting cardiac fibrosis in recent years. This review sheds light on several extracts from herbal plants, which are promising therapeutics for reversing cardiac fibrosis.

Orthobiologics with phytobioactive cues: A paradigm in bone regeneration

Bone injuries occur due to various traumatic and disease conditions. Healing of bone injury occurs via a multi-stage intricate process. Body has the potential to rectify most of the bone injuries but some severe traumatic cases with critical size defects may require interventions. Autografts are still considered the "gold standard" for fracture healing but due to limitations associated with it, new alternatives are warranted. The field of orthobiologics has provided novel approaches using scaffolds, bioactive molecules, stem cells for the treatment of bone defects. Phyto-bioactives have been widely used in alternative medicine and folklore practices for curing bone ailments. It is believed that different bioactive constituents in plants work synergistically to give the therapeutic efficacy. Bioactives in plants extracts act upon different signal transduction pathways aiding in bone healing. The present review focuses on the use, chemical composition, mode of delivery, mechanism of action, and possible future strategies of three medicinal plants popularly used in traditional medicine for bone healing: Cissus quadrangularis, Withania somnifera and Tinospora cordifolia. Plants extracts seem to be a natural and non-toxic therapeutic alternative in treating bone injuries. Most of the studies on bone healing for these plants have reported oral administration of the extracts and presented them as a safe alternative without any side effects despite giving higher doses. Forthcoming studies could be directed towards the local delivery of extracts at the defect site. Unification of herbal extracts and orthobiologics could be an interesting direction in the field of bone healing in future. The present review intends to provide a bird's eye view of different strategies used in bone healing, mechanisms involved and future direction of advancements using phytobioactives and orthobiologics.

Stimulation of liver IGF-1 expression promotes peak bone mass achievement in growing rats: a study with pomegranate seed oil

Peak bone mass (PBM) achieved at adulthood is a strong determinant of future onset of osteoporosis, and maximizing it is one of the strategies to combat the disease. Recently, pomegranate seed oil (PSO) has been shown to have bone-sparing effect in ovariectomized mice. However, its effect on growing skeleton and its molecular mechanism remain unclear. In the present study, we evaluated the effect of PSO on PBM in growing rats and associated mechanism of action. PSO was given at various doses to 21-day-old growing rats for 90 days by oral gavage. The changes in bone parameters were assessed by micro-computed tomography and histology. Enzyme-linked immunosorbent assay was performed to analyze the levels of serum insulin-like growth factor type 1 (IGF-1). Western blotting from bone and liver tissues was done. Chromatin immunoprecipitation assay was performed to study the histone acetylation levels at IGF-1 gene. The results of the study show that PSO treatment significantly increases bone length, bone formation rate, biomechanical parameters, bone mineral density and bone microarchitecture along with enhancing muscle and brown fat mass. This effect was due to the increased serum levels of IGF-1 and stimulation of its signaling in the bones. Studies focusing on acetylation of histones in the liver, the major site of IGF-1 synthesis, showed enrichment of acetylated H3K9 and H3K14 at IGF-1 gene promoter and body. Further, the increased acetylation at H3K9 and H3K14 was associated with a reduced HDAC1 protein level. Together, our data suggest that PSO promotes the PBM achievement via increased IGF-1 expression in liver and IGF-1 signaling in bone.

Cardioprotective Effect of Ulmus wallichiana Planchon in β-Adrenergic Agonist Induced Cardiac Hypertrophy

Ulmus wallichiana Planchon (Family: Ulmaceae), a traditional medicinal plant, was used in fracture healing in the folk tradition of Uttarakhand, Himalaya, India. The present study investigated the cardioprotective effect of ethanolic extract (EE) and butanolic fraction (BF) of U. wallichiana in isoprenaline (ISO) induced cardiac hypertrophy in Wistar rats. Cardiac hypertrophy was induced by ISO (5 mg/kg/day, subcutaneously) in rats. Treatment was performed by oral administration of EE and BF of U. wallichiana (500 and 50 mg/kg/day). The blood pressure (BP) and heart rate (HR) were measured by non-invasive blood pressure measurement technique. Plasma renin, Ang II, NO, and cGMP level were estimated using an ELISA kit. Angiotensin converting enzyme activity was estimated. BP and HR were significantly increased in ISO group (130.33 ± 1.67 mmHg vs. 111.78 ± 1.62 mmHg, p < 0.001 and 450.51 ± 4.90 beats/min vs. 347.82 ± 6.91 beats/min, respectively, p < 0.001). The BP and HR were significantly reduced (EE: 117.53 ± 2.27 mmHg vs. 130.33 ± 1.67 mmHg, p < 0.001, BF: 119.74 ± 3.32 mmHg vs. 130.33 ± 1.67 mmHg, p < 0.001); HR: (EE: 390.22 ± 8.24 beats/min vs. 450.51 ± 4.90 beats/min, p < 0.001, BF: 345.38 ± 6.79 beats/min vs. 450.51 ± 4.90 beats/min, p < 0.001) after the treatment of EE and BF of U. wallichiana, respectively. Plasma renin, Ang II, ACE activity was decreased and NO, cGMP level were increased. The EE and BF of U. wallichiana down regulated the expression of ANP, BNP, TNF-α, IL-6, MMP9, β1-AR, TGFβ1 and up regulated NOS3, ACE2 and Mas expression level, respectively. Thus, this study demonstrated that U. wallichiana has cardioprotective effect against ISO induced cardiac hypertrophy.

Evaluation of anti-hypertensive activity of Ulmus wallichiana extract and fraction in SHR, DOCA-salt- and L-NAME-induced hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ulmus wallichiana Planchon (Himalayan Elm), a traditional medicinal plant, used in fracture healing in folk tradition of Uttarakhand, Himalaya, India. It is also used as diuretic. U. rhynchophylla, native to China, known as Gou Teng in Chinese medicine, is used for hypertension (WHO). U. macrocarpa has antihypertensive and vasorelaxant activity. However, no detailed studies related to hypertension have been reported previously, so we have explored the antihypertensive activity of U. wallichiana.

AIM OF THE STUDY

To investigate the pharmacological effect of ethanolic extract (EE) and butanolic fraction (BF) of U. wallichiana in hypertensive rats.

MATERIALS AND METHODS

SHR, DOCA-salt- and L-NAME-induced hypertension models were used. Treatment was performed by oral administration of EE and BF of U. wallichiana (500mg/kg/day and 50mg/kg/day) for 14 days. Then blood pressure was measured by non-invasive blood pressure (NIBP) measurement technique. Invasive blood pressure (IBP) was also reported to support the NIBP data. Concentrations of plasma renin, angiotensin II (Ang II), nitrate/nitrite (NO), cGMP were estimated. Angiotensin-converting enzyme (ACE) activity and ROS activity were also estimated.

RESULTS

Blood pressure was significantly higher in SHR as compared to normotensive wistar group (170.59±0.83mmHg vs 121.54±1.24mmHg, respectively). SBP was increased in DOCA-salt induced group compared to their control (132.77±3.90mmHg vs 107.85±5.95mmHg, respectively) and L-NAME-induced group compared to their control (168.55±5.07mmHg vs 113.03±4.13mmHg, respectively). The treatment of extract and fraction of U. wallichiana significantly decreased the blood pressure in SHR+EE (151.26±1.85mmHg, p<0.001), SHR+BF (140.44±1.16mmHg, p<0.001); DOCA+EE (113.43±5.44mmHg, p<0.05), DOCA+BF (105.09±5.12mmHg, p<0.05) and L-NAME+EE (119.76±4.39mmHg, p<0.001), L-NAME+BF (117.50±7.27mmHg, p<0.001) compared to their respective diseased control groups. The plasma renin, Ang II and ACE activity were also significantly decreased and augmented the NO and cGMP levels. It also down regulated the expression of Renin, ACE, NOS3 and TGF-β1 at mRNA levels.

CONCLUSIONS

The EE and BF probably reducing the BP via Renin-angiotensin-aldosterone system and NO/cGMP signaling pathway. The decrease in blood pressure may be due to presence of quercetin analogue flavonoids (2S,3S)-(+)-3',4',5,7-tetrahydroxydihydroflavonol-6-C-β-D-glucopyranoside; 6-Glucopyranosyl-3,3',4',5,7-pentahydroxyflavone; 6-Glucopyranosyl-4',5,7-trihydroxyflavanone and (2S,3S)-(+)-4',5,7-trihydroxydihydroflavonol-6-C-β-D-glucopyranoside, may be due to its antioxidant activity. Thus EE and BF of U. wallichiana found to have the potential ability to be used as herbal medicament to treat hypertension.

Potential osteogenic activity of ethanolic extract and oxoflavidin isolated from Pholidota articulata Lindley

ETHNOPHARMACOLOGICAL RELEVANCE

Pholidota articulata Lindley (PA) locally known as Hadjojen (bone jointer) belongs to family Orchidaceae is used for healing fractures in folklore tradition of Kumaon region of Uttarakhand, Himalaya, India. Bone is a dynamic organ and is constantly being remodeled in order to facilitate growth and repair. This process requires the involvement of bone forming osteoblast and bone resorbing osteoclast cells, which function in generating and mineralizing bone, giving strength and rigidity to the skeletal system. Present study was aimed to determine the therapeutic potential of ethanolic extract of PA and its isolated compound oxoflavidin, by characterizing their fracture healing properties.

MATERIALS AND METHODS

Ovariectomized (Ovx) estrogen deficient adult female Balb/c mice were used for in vivo evaluation of osteogenic or bone healing potential of ethanolic extract of PA. Further, its isolated compounds were tested for their osteogenic efficacy using alkaline phosphatase assay and mineralization assay in vitro in mice calvarial osteoblasts.

RESULTS

The ethanolic extract of PA exhibited significant restoration of trabecular micro-architecture in both femoral and tibial bones. Additionally, treatment with PA extract led to better bone quality and devoid of any uterine estrogenicity in ovariectomized estrogen deficient mice. One of the isolated compound, oxoflavidin enhanced ALP activity (a marker of osteoblast differentiation), mineral nodule formation and mRNA levels of osteogenic markers like BMP-2, Type 1 Collagen, RUNX-2 and osteocalcin.

CONCLUSION

These results warrant that ethanolic extract of PA and it's pure compound oxoflavidin have fracture healing properties. The extract and oxoflavidin exhibit a strong threapeutical potential for the treatment and management of postmenopausal osteoporosis.

Ethanol extract of Peperomia pellucida (Piperaceae) promotes fracture healing by an anabolic effect on osteoblasts

ETHNOPHARMACOLOGICAL RELEVANCE

The whole plant or some part of Peperomia pellucida (L.) HBK is used in some parts of Cameroon as a treatment for fracture healing.

AIM OF THE STUDY

To evaluate the effect of ethanolic extracts of Peperomia pellucida (L.), a Cameroonian medicinal plant on bone regeneration following bone and marrow injury, and determine the mode of action.

MATERIALS AND METHODS

Ethanol extract of Peperomia pellucida was administered at 100 and 200mg/kg doses orally to adult female Sprague-Dawley rats having a drill hole injury (0.8mm) in the femur diaphysis. Vehicle (gum-acacia in distilled water) was given to the control group. After 12 days of treatment, animals were euthanized and femur bones collected. Confocal microscopy of calcein labeling at the drill hole site was performed to evaluate bone regeneration. 3-D microarchitecture of drill hole site was analyzed by micorocomputed tomography. Osteogenic effects of the extract were evaluated by assessing mineralized nodule formation of bone marrow stromal cells and expression of osteogenic genes (mRNA level of type-1 collagen, bone morphogenetic protein-2 and osteocalcin genes) in the femur.

RESULTS

Ethanol extract from Peperomia Pellucida (L.) dose-dependently induced bone regeneration at the fracture site. At 200mg/kg dose, the extract significantly increased mineral deposition compared to controls. The extract also improved microarchitecture of the regenerating bone evident from increased bone volume fraction, trabecular thickness, trabecular number, and decreased trabecular separation and structure model index. In addition, the extract increased the formation of mineralized nodules from the bone marrow stromal cells. Furthermore, the extract induced the expression of osteogenic genes in the femur including type 1 collagen, osteocalcin and BMP-2, compared to control.

CONCLUSION

Ethanolic extract of P. pellucid (L.) accelerates fracture repair in rats via stimulatory effects on osteoblast differentiation and mineralization, thereby justifying its traditional use.

Greater Skeletal Gains in Ovary Intact Rats at Maturity Are Achieved by Supplementing a Standardized Extract of Butea monosperma Stem Bark that Confers Better Bone Conserving Effect following Ovariectomy and Concurrent Treatment Withdrawal

With a longitudinally designed study, we tested whether an acetone soluble fraction (ASF) from the stem bark of Butea monosperma resulted in maximizing bone gain in rats during growth and maturation and thus protected against osteopenia following ovariectomy (OVx) with concomitant treatment withdrawal. Female rats at weaning were given ASF (100 mg/kg/d) or vehicle for 12 weeks, and baseline skeletal parameters (micro-CT) and total plasma antioxidant status (TAS) were measured. At this stage, one group was OVx and the other group was sham operated. Vehicle group (untreated) after OVx was given E2 or continued with vehicle (OVx control). ASF group after OVx was given vehicle (ASF withdrawn, ASFW). After another 12 weeks, all groups were killed and various skeletal parameters were determined. ASF resulted in substantially better skeletal parameters and higher plasma TAS over control at maturity. Rats treated with ASF before OVx had reduced rates of bone loss compared to OVx control. Twelve weeks after OVx, the ASFW group exhibited better trabecular microarchitectural preservation, bone turnover profiles, increased cortical deposition, and biomechanical strength over the OVx control, and the effects were comparable to OVx + E2 group. ASF supplementation during skeletal growth could maximize bone accrual and could confer increased resistance to post-OVx osteopenia despite treatment withdrawal.

Positive skeletal effects of cladrin, a naturally occurring dimethoxydaidzein, in osteopenic rats that were maintained after treatment discontinuation

Effects of cladrin treatment and withdrawal in osteopenic rats were studied. Cladrin improved trabecular microarchitecture, increased lumbar vertebral compressive strength, augmented coupled remodeling, and increased bone osteogenic genes. A significant skeletal gain was maintained 4 weeks after cladrin withdrawal. Findings suggest that cladrin has significant positive skeletal effects.

INTRODUCTION

We showed that a standardized extract of Butea monosperma preserved trabecular bone mass in ovariectomized (OVx) rats. Cladrin, the most abundant bioactive compound of the extract, promoted peak bone mass achievement in growing rats by stimulating osteoblast function. Here, we studied the effects of cladrin treatment and withdrawal on the osteopenic bones.

METHODS

Adult female Sprague-Dawley rats were OVx and left untreated for 12 weeks to allow for significant estrogen deficiency-induced bone loss, at which point cladrin (1 and 10 mg/kg/day) was administered orally for another 12 weeks. Half of the rats were killed at the end of the treatments and the other half at 4 weeks after treatment withdrawal. Sham-operated rats and OVx rats treated with PTH or 17β-estradiol (E2) served as various controls. Efficacy was evaluated by bone microarchitecture using microcomputed tomographic analysis and fluorescent labeling of bone. qPCR and western blotting measured mRNA and protein levels in bone and uterus. Specific ELISA was used for measuring levels of serum PINP and urinary CTx.

RESULTS

In osteopenic rats, cladrin treatment dose dependently improved trabecular microarchitecture, increased lumbar vertebral compression strength, bone formation rate (BFR), cortical thickness (Cs.Th), serum PINP levels, and expression of osteogenic genes in bones; and reduced expression of bone osteoclastogenic genes and urinary CTx levels. Cladrin had no uterine estrogenicity. Cladrin at 10 mg/kg maintained acquired skeletal gains 4 weeks after withdrawal.

CONCLUSION

Cladrin had positive skeletal effects in osteopenic rats that were maintained after treatment withdrawal.

Potential antiosteoporotic agents from plants: a comprehensive review

Osteoporosis is a major health hazard and is a disease of old age; it is a silent epidemic affecting more than 200 million people worldwide in recent years. Based on a large number of chemical and pharmacological research many plants and their compounds have been shown to possess antiosteoporosis activity. This paper reviews the medicinal plants displaying antiosteoporosis properties including their origin, active constituents, and pharmacological data. The plants reported here are the ones which are commonly used in traditional medical systems and have demonstrated clinical effectiveness against osteoporosis. Although many plants have the potential to prevent and treat osteoporosis, so far, only a fraction of these plants have been thoroughly investigated for their physiological and pharmacological properties including their mechanism of action. An attempt should be made to highlight plant species with possible antiosteoporosis properties and they should be investigated further to help with future drug development for treating this disease.

A naturally occurring naringenin derivative exerts potent bone anabolic effects by mimicking oestrogen action on osteoblasts

BACKGROUND AND PURPOSE

Naringenin and its derivatives have been assessed in bone health for their oestrogen-'like' effects but low bioavailability impedes clinical potential. This study was aimed at finding a potent form of naringenin with osteogenic action.

EXPERIMENTAL APPROACH

Osteoblast cultures were harvested from mouse calvaria to study differentiation by naringenin, isosakuranetin, poncirin, phloretin and naringenin-6-C-glucoside (NCG). Balb/cByJ ovariectomized (OVx) mice without or with osteopenia were given naringenin, NCG, 17β-oestradiol (E2) or parathyroid hormone (PTH). Efficacy was evaluated by bone microarchitecture using microcomputed tomography and determination of new bone formation by fluorescent labelling of bone. Plasma levels of NCG and naringenin were determined by HPLC.

KEY RESULTS

NCG stimulated osteoblast differentiation more potently than naringenin, while isosakuranetin, poncirin or phloretin had no effect. NCG had better oral bioavailability than naringenin. NCG increased the mRNA levels of oestrogen receptors (ERs) and bone morphogenetic protein (an ER responsive gene) in vivo, more than naringenin. In OVx mice, NCG treatment in a preventive protocol increased bone formation rate (BFR) and improved trabecular microarchitecture more than naringenin or E2. In osteopenic mice, NCG but not naringenin, in a therapeutic protocol, increased BFR and improved trabecular microarchitecture, comparable with effects of PTH treatment. Stimulatory effects of NCG on osteoblasts were abolished by an ER antagonist. NCG transactivated ERβ but not ERα. NCG exhibited no uterine oestrogenicity unlike naringenin.

CONCLUSIONS AND IMPLICATIONS

NCG is a potent derivative of naringenin that has bone anabolic action through the activation of osteoblast ERs and exhibited substantial oral bioavailability.

In vivo efficacy studies of layer-by-layer nano-matrix bearing kaempferol for the conditions of osteoporosis: a study in ovariectomized rat model

A prototype formulation based on layer-by-layer (LbL) nano-matrix was developed to increase bioavailability of kaempferol with improved retention in bone marrow to achieve enhanced bone formation. The layer-by-layer nano-matrix was prepared by sequential adsorption of biocompatible polyelectrolytes over the preformed kaempferol-loaded CaCO(3) template. The system was pharmaceutically characterized and evaluated for osteogenic activity in ovariectomized (OVx) rats. Data have been compared to the standard osteogenic agent parathyroid hormone (PTH). Single oral dose of kaempferol loaded LbL nano-matrix formulation increased bioavailability significantly compared to unformulated kaempferol. Three months of Formulated kaempferol administration to osteopenic rats increased plasma and bone marrow Kaempferol levels by 2.8- and 1.75-fold, respectively, compared to free Kaempferol. Formulated Kaempferol increased bone marrow osteoprogenitor cells, osteogenic genes in femur, bone formation rate, and improved trabecular micro-architecture. Withdrawal of Formulated kaempferol-in OVx rats resulted in the maintenance of bone micro-architecture up to 30days, whereas micro-architectural deterioration was readily observed in OVx rats treated with unformulated kaempferol-within 15days of withdrawal. The developed novel formulation has enhanced anabolic effect in osteopenic rats through increased stimulatory effect in osteoblasts. Treatment post-withdrawal sustenance of formulated kaempferol could become a strategy to enhance bioavailability of flavanoids.

Evaluation of Cameroonian plants towards experimental bone regeneration

ETHNOPHARMACOLOGICAL RELEVANCE

Elephantopus mollis, Spilanthes africana, Urena lobata, Momordica multiflora, Asystasia gangetica and Brillantaisia ovariensis are used in Cameroonian traditional medicine for the treatment of bone diseases and fracture repair. The aim of this study was to evaluate the effect of ethanolic extracts of six Cameroonian medicinal plants on bone regeneration following bone and marrow injury.

MATERIALS AND METHODS

Ethanol extract of Cameroonian medicinal plants were administered (each extract at 250, 500 and 750mg/kg doses) orally to adult female Sprague-Dawley rats having a drill hole injury (0.8mm) in the femur diaphysis. Vehicle (gum-acacia in distilled water) was given to the control group. After 12 days of treatment, animals were euthanized and femur bones collected. Confocal microscopy of fractured bone was performed to evaluate bone regeneration (calcein labeling). Only active plant extracts were used for further experiments. Thus, callus was analyzed by microcomputed tomography. Osteogenic effects of the extracts were evaluated by assessing mineralized nodules formation of bone marrow stromal cells and osteoblast recruitment at drill hole site by immunohistochemistry.

RESULTS

Ethanolic extract of the leaves and twigs of Elephantopus mollis (EM) and whole plant of Spilanthes africana (SA) dose-dependently stimulated bone regeneration at the drill hole site. EM at 250 and 750mg/kg doses and SA at 750mg/kg dose significantly increased mineral deposition compared to controls. Both extracts at 500 and 750mg/kg doses improved microarchitecture of the regenerating bone evident from increased bone volume fraction, trabecular thickness, trabecular number, and decreased trabecular separation and structure model index. EM and SA extracts increased the formation of mineralized nodules from the bone marrow stromal cells. In addition, EM and SA extracts increased osteoblast recruitment at the drill hole site evident from increased Runx-2 positive cells following their treatments compared to control.

CONCLUSION

Ethanolic extracts of EM and SA accelerate fracture repair in rats via stimulatory effects on osteoblast differentiation and mineralization, thereby justifying their traditional use.

Protective effect of Sideritis euboea extract on bone mineral density and strength of ovariectomized rats

OBJECTIVE

The aim of this study was to investigate the potential protective effect of Sideritis euboea extract (SID), commonly consumed as "mountain tea," on bone mineral density (BMD) and the strength of the ovariectomized (OVX) rat model of osteoporosis.

METHODS

Thirty-two 10-month-old Wistar rats were separated into controls (sham operated), OVX, and OVX plus SID in their drinking water (dose, 330 mg/kg body weight per day), starting immediately after OVX for 6 months. Tibial BMD at baseline and at 3 and 6 months post-OVX, three-point-bending of the femur, and body and uterine weight at the study end were examined.

RESULTS

BMD percentage change from baseline of the whole tibia was similar in control and OVX + SID rats at 3 months (-3.02% vs -4.67%, P = not significant), revealing a strong osteoprotective effect. At 6 months, the corresponding changes were -6.02% versus -14.37%, P < 0.05, indicating a greater bone loss in treated rats, albeit significantly less than the OVX change (-20.46%; OVX vs OVX + SID, P < 0.05). The proximal (metaphyseal) tibial BMD percentage change from baseline to 3 and 6 months between the OVX and OVX + SID groups (-26.47% vs -15.57% and -31.22% vs -16.57%, respectively) was statistically significant, demonstrating that SID preserved the proximal tibial BMD of the OVX + SID group significantly. Three-point-bending showed a significant increase in the treated compared with the OVX groups. Body and uterine weights were similar in the OVX and treated groups.

CONCLUSIONS

SID significantly protected tibial bone loss and improved femoral biomechanical strength in OVX + SID rats compared with OVX rats.

A naturally occurring rare analog of quercetin promotes peak bone mass achievement and exerts anabolic effect on osteoporotic bone

The effect of quercetin C-glucoside (QCG) on osteoblast function in vitro and bone formation in vivo was investigated. QCG supplementation promoted peak bone mass achievement in growing rats and new bone formation in osteopenic rats. QCG has substantial oral bioavailability. Findings suggest a significant bone anabolic effect of QCG.

INTRODUCTION

Recently, we showed that extracts of Ulmus wallichiana promoted peak bone mass achievement in growing rats and preserved trabecular bone mass and cortical bone strength in ovariectomized (OVx) rats. 3,3',4',5,7-Pentahydroxyflavone-6-C-β-D-glucopyranoside, a QCG, is the most abundant bioactive compound of U. wallichiana extract. We hypothesize that QCG exerts bone anabolic effects by stimulating osteoblast function.

METHODS

Osteoblast cultures were harvested from rat calvaria and bone marrow (BM) to study differentiation and mineralization. In vivo, growing female Sprague Dawley rats and OVx rats with osteopenia were administered QCG (5.0 or 10.0 mg kg(-1) day(-1)) orally for 12 weeks. Efficacy was evaluated by examining changes in bone microarchitecture using histomorphometric and microcomputed tomographic analyses and by determination of new bone formation by fluorescent labeling of bone. Plasma and BM levels of QCG were determined by high-performance liquid chromatography.

RESULTS

QCG was much more potent than quercetin (Q) in stimulating osteoblast differentiation, and the effect of QCG was not mediated by estrogen receptors. In growing rats, QCG increased BM osteoprogenitors, bone mineral density, bone formation rate, and cortical deposition. In osteopenic rats, QCG treatment increased bone formation rate and improved trabecular microarchitecture. Comparison with the sham group (ovary intact) revealed significant restoration of trabecular bone in osteopenic rats treated with QCG. QCG levels in the BM were ~50% of that of the plasma levels.

CONCLUSION

QCG stimulated modeling-directed bone accrual and exerted anabolic effects on osteopenic rats by direct stimulatory effect on osteoprogenitors likely due to substantial QCG delivery at tissue level following oral administration.

A novel quercetin analogue from a medicinal plant promotes peak bone mass achievement and bone healing after injury and exerts an anabolic effect on osteoporotic bone: the role of aryl hydrocarbon receptor as a mediator of osteogenic action

We recently reported that extracts made from the stem bark of Ulmus wallichiana promoted peak bone mass achievement in growing rats and preserved trabecular bone mass and cortical bone strength in ovariectomized (OVX) rats. Further, 6-C-β-D-glucopyranosyl-(2S,3S)-(+)-3',4',5,7-tetrahydroxyflavanol (GTDF), a novel flavonol-C-glucoside isolated from the extracts, had a nonestrogenic bone-sparing effect on OVX rats. Here we studied the effects of GTDF on osteoblast function and its mode of action and in vivo osteogenic effect. GTDF stimulated osteoblast proliferation, survival, and differentiation but had no effect on osteoclastic or adipocytic differentiation. In cultured osteoblasts, GTDF transactivated the aryl hydrocarbon receptor (AhR). Activation of AhR mediated the stimulatory effect of GTDF on osteoblast proliferation and differentiation. Furthermore, GTDF stimulated cAMP production, which mediated osteogenic gene expression. GTDF treatments given to 1- to 2-day-old rats or adult rats increased the mRNA levels of AhR target genes in calvaria or bone marrow stromal cells. In growing female rats, GTDF promoted parameters of peak bone accrual in the appendicular skeleton, including increased longitudinal growth, bone mineral density, bone-formation rate (BFR), cortical deposition, and bone strength. GTDF promoted the process of providing newly generated bone to fill drill holes in the femurs of both estrogen-sufficient and -deficient rats. In osteopenic OVX rats, GTDF increased BFR and significantly restored trabecular bone compared with the ovaries-intact group. Together our data suggest that GTDF stimulates osteoblast growth and differentiation via the AhR and promotes modeling-directed bone accrual, accelerates bone healing after injury, and exerts anabolic effects on osteopenic rats likely by a direct stimulatory effect on osteoprogenitors. Based on these preclinical data, clinical evaluation of GTDF as a potential bone anabolic agent is warranted.

Quercetin-6-C-β-D-glucopyranoside isolated from Ulmus wallichiana planchon is more potent than quercetin in inhibiting osteoclastogenesis and mitigating ovariectomy-induced bone loss in rats

OBJECTIVE

The aim of this study was to determine the skeletal effect of quercetin-6-C-β-D-glucopyranoside (QCG) isolated from the extract of Ulmus wallichiana and compare this effect with quercetin (Q) in a rat model of postmenopausal bone loss.

METHODS

Murine bone marrow cells were used to study the effect of QCG or Q on osteoclast differentiation. QCG or Q (1.0 and 5.0 mg kg(-1) d(-1) doses) was administered orally to ovarietomized (OVx) rats for 12 weeks. Sham-operated + vehicle and OVx + vehicle groups served as positive and negative controls, respectively. Bone mineral density, bone microarchitecture, biomechanical strength, bone turnover markers, and uterotrophic effect were studied. One-way analysis of variance was used to test significance of effects.

RESULTS

QCG at 1.0 nM significantly inhibited differentiation of multinucleated osteoclasts and expression of osteoclastogenic genes from bone marrow cells, whereas Q at 10.0 μM had comparable results. OVx rats treated with QCG exhibited significantly higher bone mass and better microarchitecture in trabecular and cortical bones compared with OVx + vehicle. QCG treatment of OVx rats had better functional impact than did Q-treated OVx rats, evident from increased bone biomechanical strength. Serum osteocalcin and urinary fragments of type 1 collagen were significantly lower in QCG-treated OVx rats compared with OVx + vehicle group. The protective effect of QCG under ovariectomy-induced bone loss setting was found to be significantly better than Q. Uterine histomorphometry parameters of OVx rats did not change with QCG treatment.

CONCLUSIONS

QCG improves bone biomechanical quality more effectively than Q through positive modifications of bone mineral density and bone microarchitecture without a hyperplastic effect on the uterus.

Medicarpin, a legume phytoalexin, stimulates osteoblast differentiation and promotes peak bone mass achievement in rats: evidence for estrogen receptor β-mediated osteogenic action of medicarpin

Dietary isoflavones including genistein and daidzein have been shown to have favorable bone conserving effects during estrogen deficiency in experimental animals and humans. We have evaluated osteogenic effect of medicarpin (Med); a phytoalexin that is structurally related to isoflavones and is found in dietary legumes. Med stimulated osteoblast differentiation and mineralization at as low as 10⁻¹⁰ M. Studies with signal transduction inhibitors demonstrated involvement of a p38 mitogen activated protein kinase-ER-bone morphogenic protein-2 pathway in mediating Med action in osteoblasts. Co-activator interaction studies demonstrated that Med acted as an estrogen receptor (ER) agonist; however, in contrast to 17β-estradiol, Med had no uterine estrogenicity and blocked proliferation of MCF-7 cells. Med increased protein levels of ERβ in osteoblasts. Selective knockdown of ERα and ERβ in osteoblasts established that osteogenic action of Med is ERβ-dependent. Female Sprague-Dawley (weaning) rats were administered Med at 1.0- and 10.0 mg.kg⁻¹ doses by gavage for 30 days along with vehicle control. Med treatment resulted in increased formation of osteoporgenitor cells in the bone marrow and osteoid formation (mineralization surface, mineral apposition/bone formation rates) compared with vehicle group. In addition, Med increased cortical thickness and bone biomechanical strength. In pharmacokinetic studies, Med exhibited oral bioavailability of 22.34% and did not produce equol. Together, our results demonstrate Med stimulates osteoblast differentiation likely via ERβ, promotes achievement of peak bone mass, and is devoid of uterine estrogenicity. In addition, given its excellent oral bioavailability, Med can be potential osteogenic agent.

Medicarpin inhibits osteoclastogenesis and has nonestrogenic bone conserving effect in ovariectomized mice

Medicarpin, a pterocarpan class of naturally occurring benzopyran furanobenzene compound was synthesized in gram scale to investigate its effects on murine bone cells and in ovariectomized (OVx) mice. Medicarpin, at as low as 10(-10)M suppressed osteoclastogenesis in bone marrow cells (BMCs). Medicarpin-induced apoptosis of mature osteoclasts isolated from long bones. Effects of medicarpin in osteoclasts appear to be independent of estrogen receptor (ER) activation as ICI 180,782 failed to abrogate its effects on osteoclasts. In calvarial osteoblasts, medicarpin (10(-10)M) blocked nuclear factor kappaB (NF-kappaB) signaling assessed by tumor necrosis factor alpha (TNFalpha)-stimulated nuclear translocation of p65 subunit of NF-kappaB. Medicarpin also inhibited the expression of TNFalpha in mouse calvarial osteoblasts. This effect was ER dependent as ICI 180,782 reversed the suppressive effect of medicarpin on TNFalpha mRNA levels in osteoblasts. In addition, like 17beta-estradiol, presence of medicarpin inhibited TNFalpha-induced upregulation of interleukin-1, and -6 mRNA levels in osteoblasts. In co-cultures consisting of calvarial osteoblasts and BMCs, presence of medicarpin increased osteoprotegerin (OPG)/receptor activator of NF-kappaB ligand (RANKL) ratio and reduced mRNA levels of osteoclast markers including tartrate-resistant acid phosphatase and RANK. OVx mice administered medicarpin (10.0mgkg(-1)day(-1)) orally for 30days had reduced formation of osteoclasts but increased formation of osteoprogenitor cells in BMCs compared with OVx+vehicle group. Medicarpin treatment to OVx mice maintained parameters of trabecular microarchitecure. Medicarpin exhibited no uterine estrogenicity. Our findings point towards direct and indirect inhibitory effects of medicarpin on osteoclastogenesis in vitro that contribute to its bone sparing effect in OVx mice.

A novel flavonoid, 6-C-beta-d-glucopyranosyl-(2S,3S)-(+)-3',4',5,7-tetrahydroxyflavanone, isolated from Ulmus wallichiana Planchon mitigates ovariectomy-induced osteoporosis in rats

OBJECTIVE

The aim of this study was to determine the skeletal effect of 6-C-beta-d-glucopyranosyl-(2S,3S)-(+)-3',4',5,7-tetrahydroxyflavanone (GTDF)/Ulmoside A, a new compound isolated from the extract of Ulmus wallichiana in a rat model of postmenopausal bone loss.

METHODS

GTDF (1.0 and 5.0 mg kg d) was given orally to ovariectomized (OVx) rats (180-200 g) for 12 weeks. Sham operated + vehicle, ovariectomy + 17beta-estradiol (2.5 microg kg d), and ovariectomy + vehicle groups served as various controls. Bone mineral density (BMD), trabecular microarchitecture, bone biomechanical strength, levels of bone turnover/resorption markers, uterotropic effect, and plasma pharmacokinetics were studied. One-way analysis of variance was used to test significance of effects.

RESULTS

OVx rats treated with both doses of GTDF exhibited significantly higher BMD in the trabecular (distal femur, proximal tibia, and vertebrae) and cortical (femur shaft) regions compared with the ovariectomy + vehicle group. Micro-CT demonstrated that OVx rats treated with 5.0 mg kg day of GTDF had better bone microarchitectural parameters compared with the ovariectomy + vehicle group. Serum osteocalcin and urinary C-terminal teleopeptide of Type I collagen levels in OVx rats treated with GTDF (at both doses) were significantly lower than those in the ovariectomy + vehicle group. At neither of the two doses did GTDF exhibit uterine estrogenicity. A pharmacokinetic study revealed that GTDF achieved maximum plasma concentration (40.67 ng mL) at approximately 1 hour, indicating its slow absorption. Its absolute bioavailability was found to be 1.04% with a plasma elimination half-life of approximately 5 hours.

CONCLUSIONS

GTDF, a novel compound isolated from U wallichiana extract, improves bone biomechanical quality through positive modifications of BMD and trabecular microarchitecture without a hyperplastic effect on the uterus.