ecdysterone and Osteoporosis

Osteoporosis is an aging process of skeletal tissues with characteristics of reductions in bone mass and microarchitectural deterioration of bone tissue. The present study aimed to investigate the effects of glucocorticoid‑induced osteoporosis on osteoblasts and to examine the roles of β‑ecdysterone (β‑Ecd) involved. In the present study, an in vivo model of osteoporosis was established through the subcutaneous implantation of prednisolone (PRED) into Sprague‑Dawley rats, with or without a subcutaneous injection of β‑Ecd (5 or 10 mg/kg body weight). Expression of Beclin‑1 and microtubule‑associated protein 1A/1B‑light chain 3I/II and apoptosis in lumbar vertebrae tissues was measured by immunofluorescence and TUNEL assays, respectively. Serum concentration of calcium and phosphorus, and the activity of tartrate‑resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) were measured by biochemical assay. Reverse transcription‑quantitative polymerase chain reaction and western blotting was used for detect the expression of related genes and proteins. PRED treatment inhibited bone formation by decreasing bone mineral density, and suppressing the expression of Runt‑related transcription factor 2 and bone morphogenetic protein 2, while enhancing the activity of alkaline phosphatase, upregulating the expression of receptor activator of nuclear factor-κB ligand, and increasing the serum content of calcium, phosphorus and tartrate‑resistant acid phosphatase in rats. Additionally, PRED was revealed to inhibit autophagy through the downregulation of Beclin‑1, autophagy protein 5 and microtubule‑associated protein 1A/1B‑light chain 3I/II expression, whereas it induced the apoptosis, through the activation of caspase‑3 and the suppression of apoptosis regulator BCL2 expression. Notably, the PRED‑induced alterations in bone formation, autophagy and apoptosis were revealed to be attenuated by β‑Ecd administration. In conclusion, the findings of the present study suggested that β‑Ecd may be a promising candidate for the development of therapeutic strategies for the treatment of osteoporosis, through the induction of autophagy and the inhibition of apoptosis in vivo.

Topics: Animals; Apoptosis; Apoptosis Regulatory Proteins; Autophagy; Bone Density Conservation Agents; Drug Evaluation, Preclinical; Ecdysterone; Gene Expression; Male; Osteoblasts; Osteoporosis; Rats, Sprague-Dawley

Ecdysteroids are steroids found in invertebrates and plants. In mammals they have protein anabolic effects. We have recently published antiosteoporotic effects of Tinospora cordifolia (TC) extract and the search for the possible active ingredients yielded the presence of beta-Ecdysone (Ecd). Therefore, we investigated the effects of pure Ecd in ovariectomized rats on morphological changes in joint, epiphyseal cartilage and trabecular tissue. Following ovariectomy rats were fed for 1 month with Ecd containing food at a dose of 52.8 mg/day/animal. Positive and negative control animals received 17-beta Estradiol (E(2), 132 microg/day/animal) and soy free (sf) food respectively. At sacrifice, specimens consisting of upper tibiae-lower femurs and knee joint were harvested and processed for histomorphometry. The parameters measured included thickness of the joint cartilage, thickness of the whole epiphyseal growth plate and its three zones. Furthermore, the percentage of trabecular bone in the metaphysis region of tibiae was quantified. Ecd and E(2) induced a significant increase in the thickness of joint cartilage. The whole epiphyseal growth plate and its proliferative and hypertrophic zones were also increased by Ecd whereas E(2) reduced their size. The percentage of trabecular area in the metaphysis of tibia was significantly increased in Ecd and E(2) treated animals. Results provide a plausible explanation for the antiosteoporotic effects of TC. Hence, TC as well as other Ecd producing plants or pure Ecd may be of value in the prevention and treatment of osteoporosis and osteoarthritis which is of increasing importance due to aging and obesity among individuals.

Topics: Animals; Bone and Bones; Bone Density; Bone Density Conservation Agents; Diet; Drug Therapy, Combination; Ecdysterone; Estradiol; Female; Femur; Growth Plate; Knee Joint; Osteoarthritis, Knee; Osteoporosis; Ovariectomy; Phytotherapy; Plant Extracts; Rats; Rats, Wistar; Soy Foods; Tibia; Tinospora

Estrogens exert beneficial effects in the bone. Their chronic use however bares several risks. Therefore intensive search for non-estrogenic, bone protective compounds is going on. We observed that an extract of Tinospora cordifolia has antiosteoporotic effects and identified 20-OH-Ecdysone (beta-Ecdysone=Ecd) as a possible candidate for this action. Ovariectomized (ovx) rats were treated orally over 3 months with no Ecd (control) or 18, 57 or 121 mg Ecd/day/animal. Estradiol-17beta benzoate (E2) 159 microg/day/animal) fed animals served as positive controls. Bone mineral density (BMD) of tibia was measured by quantitative computer tomography, serum Osteocalcin and CrossLaps were measured in a ligand binding assay. Utilizing an estrogen receptor (ER) containing cytosolic extract of porcine uteri the capability of Ecd to bind to ER was tested. Ecd did not bind to ER. BMD was reduced by more than 50% in the control. In the Ecd animals BMD was dose dependently higher. Serum CrossLaps was lower in the Ecd and E2 group while serum Osteocalcin levels were decreased in the E2 but increased in the Ecd fed animals. Ecd has an antiosteoporotic effect which does not involve activation of ER.

Topics: Animals; Bone Density; Bone Density Conservation Agents; Collagen; Dose-Response Relationship, Drug; Ecdysterone; Female; Osteocalcin; Osteoporosis; Ovariectomy; Peptide Fragments; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Receptors, Estrogen; Swine; Tinospora; Uterus

The effect on bone tissue of beta-ecdysterone, a type of ecdysteroid found in many plants, has not been previously investigated. In this study, we found that beta-ecdysterone treatment significantly induced alkaline phosphatase (ALP) activity in mesenchymal stem cells in a dose-dependent manner. Real-time polymerase chain reaction (PCR) showed that Runx2, osteocalcin, and type I collagen expression also increased. ICI182780, a specific estrogen receptor antagonist, inhibited the upregulation of ALP activity. Moreover, beta-ecdysterone promoted estrogen receptor (ER) reporter gene activity; however, ICI182780 reversed its effect, suggesting that beta-ecdysterone has stimulatory effects on osteogenic differentiation via the ER. Furthermore, beta-ecdysterone alleviated osteoporosis symptoms in a mouse model without obvious side effects. Therefore beta-ecdysterone may be a promising candidate drug for the treatment of osteoporosis.

Topics: Alkaline Phosphatase; Animals; Azo Compounds; Bone and Bones; Bone Density; Bone Density Conservation Agents; Cell Differentiation; Coloring Agents; Ecdysterone; Genes, Reporter; Indicators and Reagents; Male; Mesenchymal Stem Cells; Mice; Mice, Inbred BALB C; Osteogenesis; Osteoporosis; Receptors, Estrogen; Reverse Transcriptase Polymerase Chain Reaction; Tetrazolium Salts; Thiazoles; Transfection; Tretinoin