An Intermediate Concentration of Calcium with Antioxidant Supplement in Culture Medium Enhances Proliferation and Decreases the Aging of Bone Marrow Mesenchymal Stem Cells.

Human bone marrow stem cells (HBMSCs) are isolated from the bone marrow. Stem cells can self-renew and differentiate into various types of cells. They are able to regenerate kinds of tissue that are potentially used for tissue engineering. To maintain and expand these cells under culture conditions is difficult-they are easily triggered for differentiation or death. In this study, we describe a new culture formula to culture isolated HBMSCs. This new formula was modified from NCDB 153, a medium with low calcium, supplied with 5% FBS, extra growth factor added to it, and supplemented with N-acetyl-L-cysteine and L-ascorbic acid-2-phosphate to maintain the cells in a steady stage. The cells retain these characteristics as primarily isolated HBMSCs. Moreover, our new formula keeps HBMSCs with high proliferation rate and multiple linage differentiation ability, such as osteoblastogenesis, chondrogenesis, and adipogenesis. It also retains HBMSCs with stable chromosome, DNA, telomere length, and telomerase activity, even after long-term culture. Senescence can be minimized under this new formulation and carcinogenesis of stem cells can also be prevented. These modifications greatly enhance the survival rate, growth rate, and basal characteristics of isolated HBMSCs, which will be very helpful in stem cell research.

Green Tea Catechin (-)-Epigallocatechin-3-Gallate (EGCG) Facilitates Fracture Healing.

Green tea drinking can ameliorate postmenopausal osteoporosis by increasing the bone mineral density. (-)-Epigallocatechin-3-gallate (EGCG), the abundant and active compound of tea catechin, was proven to be able to reduce bone loss and ameliorate microarchitecture in female ovariectomized rats. EGCG can also enhance the osteogenic differentiation of murine bone marrow mesenchymal stem cells and inhibit the osteoclastogenesis in RAW264.7 cells by modulation of the receptor activator of nuclear factor-kB (RANK)/RANK ligand (RANKL)/osteoprotegrin (OPG) (RANK/RANKL/OPG) pathway. Our previous study also found that EGCG can promote bone defect healing in the distal femur partially via bone morphogenetic protein-2 (BMP-2). Considering the osteoinduction property of BMP-2, we hypothesized that EGCG could accelerate the bone healing process with an increased expression of BMP-2. In this manuscript, we studied whether the local use of EGCG can facilitate tibial fracture healing. Fifty-six 4-month-old rats were randomly assigned to two groups after being weight-matched: a control group with vehicle treatment (Ctrl) and a study group with 10 µmol/L, 40 µL, EGCG treatment (EGCG). Two days after the operation, the rats were treated daily with EGCG or vehicle by percutaneous local injection for 2 weeks. The application of EGCG enhanced callus formation by increasing the bone volume and subsequently improved the mechanical properties of the tibial bone, including the maximal load, break load, stiffness, and Young's modulus. The results of the histology and BMP-2 immunohistochemistry staining showed that EGCG treatment accelerated the bone matrix formation and produced a stronger expression of BMP-2. Taken together, this study for the first time demonstrated that local treatment of EGCG can accelerate the fracture healing process at least partly via BMP-2.

(-)-Epigallocatechin-3-gallate (EGCG) enhances healing of femoral bone defect.

BACKGROUND: Previously, we found that (-)-epigallocatechin-3-gallate (EGCG) enhanced osteogenic differentiation of murine bone marrow mesenchymal stem cells by increasing the mRNA expression of osteogenesis-related genes, alkaline phosphatase activity and eventually mineralization. We further found EGCG supplementation preserved bone mass and microarchitecture in female rats during estrogen deficiency in the proximal tibia and lumbar spine at least in part by increasing bone morphogenetic protein-2 (BMP2). BMP2 can enhance de novo bone formation. PURPOSE: In this study, we evaluate the effect of local EGCG application in de novo bone formation in bone defect healing. METHODS: Twenty-four rats aged 4 months were weight-matched and randomly allocated to 2 groups: defect control with vehicle treatment (control) and defect with 10 µM EGCG treatment (EGCG). Daily vehicle and EGCG were applied locally by percutaneous local injection 2 days after defect creation for 2 weeks. Four weeks after treatment, animals were sacrificed for micro-computed tomography (µ-CT) and biomechanical analysis. RESULTS: Local EGCG at femoral defect can enhance de novo bone formation by increasing bone volume and subsequently improve mechanical properties including max load, break point, stiffness, area under the max load curve, area under the break point curve and ultimate stress. CONCLUSIONS: Local EGCG may enhance bone defect healing via at least partly by the de novo bone formation of BMP-2.

Liposomal Encapsulation for Systemic Delivery of Propranolol via Transdermal Iontophoresis Improves Bone Microarchitecture in Ovariectomized Rats.

The stimulatory effects of liposomal propranolol (PRP) on proliferation and differentiation of human osteoblastic cells suggested that the prepared liposomes-encapsulated PRP exerts anabolic effects on bone in vivo. Iontophoresis provides merits such as sustained release of drugs and circumvention of first pass metabolism. This study further investigated and evaluated the anti-osteoporotic effects of liposomal PRP in ovariectomized (OVX) rats via iontophoresis. Rats subjected to OVX were administered with pure or liposomal PRP via iontophoresis or subcutaneous injection twice a week for 12 weeks. Changes in the microarchitecture at the proximal tibia and the fourth lumbar spine were assessed between pure or liposomal PRP treated and non-treated groups using micro-computed tomography. Administration of liposomal PRP at low dose (0.05 mg/kg) via iontophoresis over 2-fold elevated ratio between bone volume and total tissue volume (BV/TV) in proximal tibia to 9.0% whereas treatment with liposomal PRP at low and high (0.5 mg/kg) doses via subcutaneous injection resulted in smaller increases in BV/TV. Significant improvement of BV/TV and bone mineral density (BMD) was also found in the fourth lumbar spine when low-dose liposomal PRP was iontophoretically administered. Iontophoretic low-dose liposomal PRP also elevated trabecular numbers in tibia and trabecular thickness in spine. Enhancement of bone microarchitecture volumes has highlighted that liposomal formulation with transdermal iontophoresis is promising for PRP treatment at the lower dose and with longer duration than its clinical therapeutic range and duration to exhibit optimal effects against bone loss in vivo.

Exercise training ameliorates glucosamine-induced insulin resistance in ovariectomized rats.

OBJECTIVE: Glucosamine (GlcN), which has been reported to induce insulin resistance (IR), is a popular nutritional supplement used to treat osteoarthritis in menopausal women. We previously demonstrated that GlcN treatment caused IR in ovariectomized rats by reducing the expression of glucose transport protein subtype 4 (GLUT-4) in skeletal muscle. In the present study, we hypothesized that endurance exercise training can reverse GlcN-induced IR. METHODS: Fifty female rats were randomly divided into five groups with 10 rats in each group: (1) sham-operated group; (2) sham-operated group with GlcN treatment for 14 days; (3) ovariectomy (OVX) group; (4) OVX with GlcN treatment; and (5) OVX with GlcN treatment followed by exercise training (running program) for 8 weeks. RESULTS: Fasting plasma glucose increased in the OVX + GlcN group, and fasting plasma insulin and the homeostasis model assessment-insulin resistance (HOMA-IR) were significantly higher only in this group. After the rats received exercise training for 8 weeks, no increase in the fasting plasma glucose, insulin, or HOMA-IR was observed. In an intraperitoneal glucose tolerance test, the plasma glucose, plasma insulin, HOMA-IR, and glucose-insulin index were significantly elevated only in the OVX with GlcN treatment group. However, the plasma glucose, plasma insulin, HOMA-IR, and glucose-insulin index decreased after exercise training for 8 weeks, implying that GlcN-induced IR in OVX rats could be reversed through exercise. A histological analysis revealed that exercise training can reduce islet hypertrophy and maintain GLUT-4 in skeletal muscle. CONCLUSIONS: Exercise training can alleviate IR in OVX rats treated with GlcN. Islet hyperplasia was subsequently prevented. Preserving GLUT-4 expression may be one of the mechanisms by which exercise prevents IR.

The Fractionated Toona sinensis Leaf Extract Induces Apoptosis of Human Osteosarcoma Cells and Inhibits Tumor Growth in a Murine Xenograft Model.

BACKGROUND: Osteosarcoma is a malignant bone tumor prevalent in adolescents with poor prognosis. Toona sinensis showed potent antiproliferation effect on lung, melatonin, ovary, colon, and liver cancers. However, the effects of the species on osteosarcoma cells are rarely investigated. RESULTS: In this study, we found fraction 1 of Toona sinensis leaf (TSL-1) resulted in inhibition of cell viability in MG-63, Saos-2, and U2OS osteosarcoma cell lines, while it only caused a moderate suppressive effect on normal osteoblasts. In addition, TSL-1 significantly elevated lactate dehydrogenase leakage and induced apoptosis and necrosis in Saos-2 cells. TSL-1 increased mRNA expression of pro-apoptotic factor Bad. Most important, TSL-1 significantly suppressed Saos-2 xenograft tumor growth in nude mice by increasing caspase-3. The IC-50 of TSL-1 for the 3 tested osteosarcoma cells is around 1/9 of that for lung cancer cells. CONCLUSION: We demonstrated that TSL-1, a fractionated extract from TSL, caused significant cytotoxicity to osteosarcoma cells due to apoptosis. In vivo xenograft study showed that TSL-1 suppressed the growth of osteosarcoma cells at least in part by inducing apoptosis. Our results indicate that TSL-1 has potential to be a promising anti-osteosarcoma adjuvant functional plant extract.

Rivaroxaban in preventing venous thromboembolism after arthroplastic surgery in Taiwan.

Venous thromboembolism (VTE) is one of the severe complications of total hip arthroplasty (THA) and total knee arthroplasty (TKA). The incidence of VTE could be reduced if preventive antithrombotic medicines are used; however, the incidence of bleeding may increase. Rivaroxaban is a factor Xa inhibitor that prevents VTE after THA or TKA. This study is designed to confirm the efficacy and safety of rivaroxaban in Taiwan. This is a retrospective database study based on the data of 6996 patients provided by the Taiwan National Health Insurance Research Database from 2008 to 2012. The data included the number of prescription, the cost of prescription, and case number for patients treated with antithrombotic agents for the prevention or treatment of joint arthroplasty complications (including THA, TKA, partial hip arthroplasty, revision THA and TKA), and the incidence of thrombosis and hemorrhage from year 2008 to 2012. The overall postoperative VTE rate was 0.49%. Compared with other antithrombotic drugs, rivaroxaban and heparin analogs can reduce the percentage of thrombosis. We also found that the expenditure and hospitalization was less in the rivaroxaban group than in the heparin analogs group. Because some benefits of rivaroxaban were found in our study, further cost-effective and drug safety studies are warranted. It is important to consider the cost-effective principle for the use of antithrombotic drugs in preventing thromboembolic complications after total joint arthroplasty.

Polysaccharides of Trametes versicolor Improve Bone Properties in Diabetic Rats.

This study investigates the effects of Trametes versicolor (L.:Fr.) Pilát (TVP, also known as Yunzhi) on bone properties in diabetic rats. Forty-five male Wistar rats (8 weeks old) were fed either a chow diet (control) or a high-fat diet throughout the study period of 28 days. Animals in the high-fat-diet group were injected with nicotinamide and streptozotocin to induce diabetes mellitus (DM). The DM rats were divided into a group receiving distilled water (vehicle) and another group receiving TVP at 0.1 g/kg weight by gavage. Relative to the vehicle group, TVP gavage lowered postprandial blood sugar (225 ± 18 mg/dL for TVP vs 292 ± 15 mg/dL for vehicle, p < 0.001) on day 26. Compared to the vehicle group, TVP mitigated DM-induced bone deterioration as determined by increasing bone volume of proximal tibia (22.8 ± 1.4% for TVP vs 16.8 ± 1.3% for vehicle, p = 0.003), trabecular number (p = 0.011), and femoral bone strength (11% in maximal load, 22% in stiffness, 14% in modulus, p < 0.001), and by reducing loss of femoral cortical porosity by 25% (p < 0.001). Our study demonstrates the protective effect of TVP on bone properties was mediated through, in part, the improvement of hyperglycemic control in DM animals.

17ß-estradiol protects against glucosamine-induced pancreatic ß-cell dysfunction.

OBJECTIVE: Glucosamine (GlcN) is a popular supplement for osteoarthritis in postmenopausal women. Although GlcN possibly induces insulin resistance, the effects of GlcN on ß-cell dysfunction are still obscure. METHODS: In the present study, we investigated changes in insulin production and ß-cell apoptosis in pancreatic islets after GlcN treatment in rats with or without ovariectomy and used MIN-6 cells to investigate the protective effects and molecular mechanisms of 17ß-estradiol (E2) in GlcN-induced ß-cell dysfunction. The rats were divided into four groups: (1) sham operation (SHAM; n = 8); (2) SHAM with 750 mg/kg/day GlcN injected intraperitoneally for 14 days (SHAM + GlcN; n = 10); (3) ovariectomy (OVX; n = 9); and (4) OVX with 750 mg/kg/day GlcN injected intraperitoneally for 14 days (OVX + GlcN; n = 9). RESULTS: Both GlcN and ovariectomy reduced the expression of insulin, determined by the staining intensity of insulin and reverse polymerase chain reaction. GlcN alone also induced ß-cell apoptosis, and this adverse effect was aggravated after ovariectomy. In addition, we found that GlcN decreased calcium influx and insulin secretion by decreasing the protein levels of inwardly rectifying potassium in the ATP-sensitive potassium channel. GlcN decreased the protein levels of endoplasmic reticulum (ER) stress-associated proteins, including C/EBP homologous protein, phospho-protein kinase-like endoplasmic reticulum kinase, phospho-eukaryotic initiation factor 2α, and phospho-c-Jun N-terminal kinase. Finally, GlcN decreased cell viability. E2 counteracted GlcN-mediated attenuation in intracellular calcium concentration, extracellular insulin secretion, protein levels of inwardly rectifying potassium, cell viability, and protein levels of ER stress-associated proteins. ICI182.780 inhibited these beneficial effects of E2. CONCLUSIONS: GlcN impairs insulin secretion of ß-cells by inhibiting Ca influx and enhancing ß-cell apoptosis with increases in ER stress-related proteins, whereas E2 counters these adverse effects of GlcN.

Functions and mechanisms of green tea catechins in regulating bone remodeling.

Osteoporosis is caused by an imbalance in bone remodeling, a process involving bone-building osteoblasts and bone-resorptive osteoclasts. Excessive reactive oxygen species and inflammatory responses have been shown to stimulate differentiation and function of osteoclasts while inducing osteoblast apoptosis and suppressing osteoblastic proliferation and differentiation via extracellular signal-regulated kinases (ERK), ERK-dependent nuclear factor-κB and Wnt/ß-catenin signaling pathways. The anti-oxidant and anti-inflammatory green tea catechins (GTC) have been shown to promote osteoblastogenesis, suppress osteoclastogenesis and stimulate the differentiation of mesenchymal stem cells into osteoblasts rather than adipocytes by modulating the signaling pathways. This paper reviews the pharmacokinetics and metabolism of GTC, their bone-protective activities evidenced in in vitro and in vivo studies, and the limited clinical studies supporting these preclinical findings. In light of the physical, economical, and social burdens due to osteoporosis, easily accessible and affordable preventive measures such as GTC deserves further clinical studies prior to its clinical application.

An alternative technique for the management of phalangeal enchondromas with pathologic fractures.

PURPOSE: Enchondroma of the hand with a pathologic fracture is generally treated by tumor curettage and bone grafting after the fracture has healed. However, delayed surgery postpones definitive diagnosis and prolongs the period of disability. We have treated pathologic fractures in a single stage through a modified lateral surgical approach with curettage of the tumor and stabilization using injectable calcium sulfate cement. The aim of this study was to report the outcomes of treatment with this material and the modified approach. METHODS: Between 2006 and 2010, we enrolled 8 patients with solitary hand enchondromas and pathologic fractures. The surgical procedure involved a lateral approach, an extended lateral cortical window, thorough tumor evacuation, and reconstruction of the bone defects using commercially available injectable calcium sulfate cement. We performed evaluations before surgery and in the postoperative follow-up series by radiographs and clinical assessments, including measurement of joint motion by goniometry and a visual analog pain scale. RESULTS: The average time of follow-up was 19 months (range, 12-36 mo). The pathologic fractures of all patients healed clinically and radiographically within 8 weeks after surgery, and the mean active motion arcs of the metacarpophalangeal joints and proximal interphalangeal joints of the involved digit were 90° and 94°, respectively at 3-month follow-up. All patients returned to ordinary daily activities without obvious pain by 3 months postoperatively. We found no major complications, such as unacceptable alignment, nonunion, infection, or tumor recurrence, during follow-up. CONCLUSIONS: This study demonstrated the outcomes of early management of phalangeal enchondromas with pathologic fractures using a lateral approach and injectable calcium sulfate cement for reconstruction. This combined approach avoided the need for supplemental internal fixation, allowed early mobilization, and resulted in minimal joint stiffness. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Electromagnetic fields enhance chondrogenesis of human adipose-derived stem cells in a chondrogenic microenvironment in vitro.

We tested the hypothesis that electromagnetic field (EMF) stimulation enhances chondrogenesis in human adipose-derived stem cells (ADSCs) in a chondrogenic microenvironment. A two-dimensional hyaluronan (HA)-coated well (2D-HA) and a three-dimensional pellet culture system (3D-pellet) were used as chondrogenic microenvironments. The ADSCs were cultured in 2D-HA or 3D-pellet, and then treated with clinical-use pulse electromagnetic field (PEMF) or the innovative single-pulse electromagnetic field (SPEMF) stimulation. The cytotoxicity, cell viability, and chondrogenic and osteogenic differentiations were analyzed after PEMF or SPEMF treatment. The modules of PEMF and SPEMF stimulations used in this study did not cause cytotoxicity or alter cell viability in ADSCs. Both PEMF and SPEMF enhanced the chondrogenic gene expression (SOX-9, collagen type II, and aggrecan) of ADSCs cultured in 2D-HA and 3D-pellet. The expressions of bone matrix genes (osteocalcin and collagen type I) of ADSCs were not changed after SPEMF treatment in 2D-HA and 3D-pellet; however, they were enhanced by PEMF treatment. Both PEMF and SPEMF increased the cartilaginous matrix (sulfated glycosaminoglycan) deposition of ADSCs. However, PEMF treatment also increased mineralization of ADSCs, but SPEMF treatment did not. Both PEMF and SPEMF enhanced chondrogenic differentiation of ADSCs cultured in a chondrogenic microenvironment. SPEMF treatment enhanced ADSC chondrogenesis, but not osteogenesis, when the cells were cultured in a chondrogenic microenvironment. However, PEMF enhanced both osteogenesis and chondrogenesis under the same conditions. Thus the combination of a chondrogenic microenvironment with SPEMF stimulation can promote chondrogenic differentiation of ADSCs and may be applicable to articular cartilage tissue engineering.

Fruits and dietary phytochemicals in bone protection.

Osteoporosis is a disease of bone characterized by loss of bone matrix and deterioration of bone microstructure that leads to an increased risk of fracture. Cross-sectional studies have shown a positive association between higher fruit intake and higher bone mineral density. In this review, we evaluated animal and cellular studies of dried plum and citrus and berry fruits and bioactive compounds including lycopene, phenolics, favonoids, resveratrol, phloridzin, and pectin derived from tomato, grapes, apples, and citrus fruits. In addition, human studies of dried plum and lycopene were reviewed. Animal studies strongly suggest that commonly consumed antioxidant-rich fruits have a pronounced effect on bone, as shown by higher bone mass, trabecular bone volume, number, and thickness, and lower trabecular separation through enhancing bone formation and suppressing bone resorption, resulting in greater bone strength. Such osteoprotective effects seem to be mediated via antioxidant or anti-inflammatory pathways and their downstream signaling mechanisms, leading to osteoblast mineralization and osteoclast inactivation. In future studies, randomized controlled trials are warranted to extend the bone-protective activity of fruits and their bioactive compounds. Mechanistic studies are needed to differentiate the roles of phytochemicals and other constitutes in bone protection offered by the fruits. Advanced imaging technology will determine the effective doses of phytochemicals and their metabolites in improving bone mass, microarchitecture integrity, and bone strength, which is a critical step in translating the benefits of fruit consumption on osteoporosis into clinical data.

Dietary polyphenols and mechanisms of osteoarthritis.

Osteoarthritis is a condition caused in part by injury, loss of cartilage structure and function, and an imbalance in inflammatory and anti-inflammatory pathways. It primarily affects the articular cartilage and subchondral bone of synovial joints and results in joint failure, leading to pain upon weight bearing including walking and standing. There is no cure for osteoarthritis, as it is very difficult to restore the cartilage once it is destroyed. The goals of treatment are to relieve pain, maintain or improve joint mobility, increase the strength of the joints and minimize the disabling effects of the disease. Recent studies have shown an association between dietary polyphenols and the prevention of osteoarthritis-related musculoskeletal inflammation. This review discusses the effects of commonly consumed polyphenols, including curcumin, epigallocatechin gallate and green tea extract, resveratrol, nobiletin and citrus fruits, pomegranate, as well as genistein and soy protein, on osteoarthritis with an emphasis on molecular antiosteoarthritic mechanisms.

Glucosamine-induced insulin resistance in ovariectomized rats is relevant to decreasing the expression of glucose transport protein subtype 4 in the skeletal muscle and in increasing the size of pancreatic islets.

OBJECTIVE: Glucosamine (GlcN) is a popular nutritional supplement used to treat osteoarthritis in postmenopausal women. Postmenopausal women are at higher risk of type 2 diabetes mellitus and metabolic syndrome because of ovarian hormone deficiency. We used ovariectomized (OVX) rats as the model to investigate whether GlcN would induce insulin resistance (IR) in OVX rats and the underlying mechanisms. METHODS: The rats were divided into four groups: (1) sham-operated group (SHAM), (2) SHAM with GlcN treatment (SHAM + GlcN), (3) OVX group, (4) OVX with GlcN treatment (OVX + GlcN). Intraperitoneal (IP) GlcN was given at 12 weeks after the surgical procedure for 2 weeks. The IP glucose tolerance test (IPGTT) was performed to measure plasma glucose and insulin and to calculate the clinical homeostasis model assessment-IR (HOMA-IR) and glucose-insulin index. Western blot analysis for the detection of glucose transport protein subtype 4 expression in the skeletal muscle and histopathological examination of the changes in pancreatic islets were also performed. RESULTS: Fasting plasma glucose increased in the OVX + GlcN group, and fasting plasma insulin and HOMA-IR were elevated more significantly in this group. In addition, plasma glucose, plasma insulin, HOMA-IR, and glucose-insulin index were significantly elevated only in the OVX with GlcN group after IP glucose injection, implying that IR was induced by GlcN only in female rats without the protection of ovarian hormone. In addition, we found that treatment with GlcN decreased the expression of glucose transport protein subtype 4 in the skeletal muscle and induced pancreatic islet hyperplasia only in OVX rats. CONCLUSIONS: The results demonstrate that female rats do not develop IR upon GlcN treatment except after ovariectomy. Those who take GlcN after menopause or bilateral oophorectomy should watch their blood glucose level closely, especially after meals.

Neuroprotection of green tea catechins on surgical menopause-induced overactive bladder in a rat model.

OBJECTIVE: A rat model of ovariectomy-induced voiding dysfunction has been established, which mimicked the urge incontinence in postmenopausal women. Previous studies have identified strong anti-inflammatory/antioxidant properties of green tea and its associated polyphenols. The aim of this study was to evaluate whether the green tea extract, epigallocatechin gallate (EGCG), could prevent an ovariectomy-induced overactive bladder. METHODS: The study included 48 female Sprague-Dawley rats, which were divided into four groups. After bilateral ovariectomy during the following 6-month period, 12 rats received an intraperitoneal injection of saline, 24 rats received either a low-dose (1 µM kg(-1) d(-1)) or a high-dose (10 µM kg(-1) d(-1)) EGCG intraperitoneal injection. The sham group consisted of twelve rats that were not ovariectomized. In vivo isovolumetric cystometrograms were performed in all groups before the animals were euthanized. The immunofluorescence study used neurofilament stains to evaluate intramural nerve damage. Western immunoblots and real-time polymerase chain reaction were performed to determine M2 and M3 muscarinic cholinergic receptors (MChRs) at both protein and messenger RNA (mRNA) expressions. RESULTS: Long-term ovariectomy significantly increased non-voiding contractions, whereas treatment with EGCG significantly attenuated the frequency of non-voiding contractions. Ovariectomy significantly decreased the numbers of neurofilament and increased M2 and M3 MChR protein and mRNA expressions. Treatment with EGCG restored the amount of neurofilament staining and decreased M2 and M3 MChR protein and mRNA overexpressions. CONCLUSIONS: This study confirmed that ovary hormone deficiency induced overactive bladder dysfunction via intramural nerve damage and muscarinic receptor overexpression. EGCG prevented ovariectomy-induced bladder dysfunction through neuroprotective effects in a dose-dependent fashion.

Green tea catechin enhances osteogenesis in a bone marrow mesenchymal stem cell line.

Green tea has been reported to possess antioxidant, antitumorigenic, and antibacterial qualities that regulate the endocrine system. Previous epidemiological studies found that the bone mineral density (BMD) of postmenopausal women with a habit of tea drinking was higher than that of women without habitual tea consumption. However, the effects of green tea catechins on osteogenic function have rarely been investigated. In this study, we tested (-)-epigallocatechin-3-gallate (EGCG), one of the green tea catechins, on cell proliferation, the mRNA expressions of relevant osteogenic markers, alkaline phosphatase (ALP) activity and mineralization. In a murine bone marrow mesenchymal stem cell line, D1, the mRNA expressions of core binding factors a1 (Cbfa1/Runx2), osterix, osteocalcin, ALP increased after 48 h of EGCG treatment. ALP activity was also significantly augmented upon EGCG treatment for 4 days, 7 days and 14 days. Furthermore, mineralizations assayed by Alizarin Red S and von Kossa stain were enhanced after EGCG treatment for 2-4 weeks in D1 cell cultures. However, a 24-h treatment of EGCG inhibited thymidine incorporation of D1 cells. These results demonstrated that long-term treatment of EGCG increases the expressions of osteogenic genes, elevates ALP activity and eventually stimulates mineralization, in spite of its inhibitory effect on proliferation. This finding suggests that the stimulatory effects of EGCG on osteogenesis of mesenchymal stem cells may be one of the mechanisms that allow tea drinkers to possess higher BMD.