Epithelial membrane protein 2 is a prognostic indictor for patients with urothelial carcinoma of the upper urinary tract.

Upper urinary tract urothelial carcinoma is a relatively uncommon disease and is diagnosed more frequently at advanced stages. The prognosis of these patients mainly has been related to tumor stage and grade. As a result, the definition of prognostic indicators enabling precise patient selection is mandatory for neoadjuvant or adjuvant therapies. The epithelial membrane protein (EMP2) was identified as one of the up-regulated genes by isoflavones. EMP2 overexpression suppressed foci formation, anchorage-independent growth in vitro, and tumorigenicity in severe combined immunodeficiency mice (all P < 0.05). In addition, a cross-talk between EMP2 and integrins αV and ß3 was shown in the regulation of cell adhesion and migration. Higher EMP2 expression was associated with a better progression-free survival (P = 0.008) and cancer-related death (P < 0.001). EMP2 was identified as a tumor-suppressor gene in urinary tract urothelial carcinoma and may be an innovative co-targeting candidate for designing integrin-based cancer therapy.

Caffeine regulates osteogenic differentiation and mineralization of primary adipose-derived stem cells and a bone marrow stromal cell line.

Caffeine consumption reportedly influences bone mineral density and body weight. However, the effects of caffeine on bone metabolism are still controversial, and whether the dosage of caffeine influences osteogenic differentiation is yet to be clarified. In the present study, we cultured primary adipose-derived stem cells (ADSCs) and a bone marrow stromal cell line (M2-10B4) in osteogenic differentiation media containing varying concentrations of caffeine. Caffeine had biphasic effects: 0.1 mM caffeine significantly enhanced mineralization and alkaline phosphatase (ALP) activity. Consistent with these observations, a caffeine concentration of 0.1 mM upregulated the osteogenic differentiation marker genes ALP and osteocalcin (OCN), and elevated osteoprotegerin (OPG), Runt-related transcription factor 2 (RUNX2) and Sirtuin 1 (SIRT1) levels. However, a concentration of caffeine greater than 0.3 mM suppressed the differentiation of both the cell types. These findings indicate that caffeine has a beneficial effect on ADSCs and bone marrow stromal cells, enhancing differentiation to osteoblasts; this effect, which is mediated via RUNX2 activation at low doses is significantly suppressed at high doses.

Leukemic cells resist lysosomal inhibition through the mitochondria-dependent reduction of intracellular pH and oxidants.

Acidic lysosomes are indispensable for cancer development and linked to chemotherapy resistance. Chloroquine (CQ) and functional analogues have been considered as a potential solution to overcome the cancer progression and chemoresistance by inhibiting the lysosome-mediated autophagy and multidrug exocytosis. However, their anti-cancer efficacy in most clinical trials demonstrated modest improvement. In this study, we investigated the detailed mechanisms underlying the acquired resistance of K562 leukemic cells to CQ treatment. In response to 5-80 µM CQ, the lumen pH of endosomal-lysosomal system immediately increased and gradually reached dynamic equilibrium within 24 h. Leukemic cells produced more acidic organelles to tolerate 5-10 µM CQ. CQ (20-80 µM) concentration-dependently triggered cytosolic pH (pHi) rise, G0/G1 arrest, mitochondrial depolarization/fragmentation, and necrotic/apoptotic cell death. Oxidant induction by CQ was responsible for the mitochondria-dependent cytotoxicity and partial pHi elevation. Cells that survived the CQ cytotoxicity were accompanied with increased mitochondria. Under the 80 µM CQ challenge, co-treatment with the inhibitor of F0 part of mitochondrial H+-ATP synthase, oligomycin (40 nM), prevented the elevation of oxidants as well as pHi, and attenuated stresses on mitochondria, cell survival, and cell proliferation. Besides, oligomycin-treated cells obviously displayed the lysosomal peripheralization and plasma membrane blebbing, suggesting that these cells were in process of lysosomal exocytosis and microvesicle release. Enhanced motion of these secretory processes allowed the cells to exclude CQ and repair necrotic injury. Together, the oxidant production and the proton dynamic interconnection among lysosomes, mitochondria, and cytosol are crucial for leukemic susceptibility to lysosomotropic chemotherapeutics.

Zonal-Layered Chondrocyte Sheets for Repairment of Full-Thickness Articular Cartilage Defect: A Mini-Pig Model.

The cell sheet technique is a promising approach for tissue engineering, and the present study is aimed to determine a better configuration of cell sheets for cartilage repair. For stratified chondrocyte sheets (S-CS), articular chondrocytes isolated from superficial, middle, and deep zones were stacked accordingly. Heterogeneous chondrocyte sheets (H-CS) were obtained by mixing zonal chondrocytes. The expressions of chondrocytes, cytokine markers, and glycosaminoglycan (GAG) production were assessed in an in vitro assay. The curative effect was investigated in an in vivo porcine osteochondral defect model. The S-CS showed a higher cell viability, proliferation rate, expression of chondrogenic markers, secretion of tissue inhibitor of metalloproteinase, and GAG production level than the H-CS group. The expressions of ECM destruction enzyme and proinflammatory cytokines were lower in the S-CS group. In the mini-pigs articular cartilage defect model, the S-CS group had a higher International Cartilage Repair Society (ICRS) macroscopic score and displayed a zonal structure that more closely resembled the native cartilage than those implanted with the H-CS. Our study demonstrated that the application of the S-CS increased the hyaline cartilage formation and improved the surgical outcome of chondrocyte implication, offering a better tissue engineering strategy for treating articular cartilage defects.

Shockwave Treatment Enhanced Extracellular Matrix Production in Articular Chondrocytes Through Activation of the ROS/MAPK/Nrf2 Signaling Pathway.

OBJECTIVE: Shockwave application is a potential treatment for osteoarthritis (OA), but the underlying mechanism remains unknown. Oxidative stress and a counterbalancing antioxidant system might be the key to understanding this mechanism. We hypothesized that reactive oxygen species (ROS) and the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2),which is an important regulator of cellular redox homeostasis, are plausible elements. DESIGN: Porcine chondrocytes were cultured in a 3-dimensional pellet model and subjected to shockwaves. The effects of shockwaves with various energy-flux densities on optimal extracellular matrix (ECM) synthesis were assessed. ROS, mitogen-activated protein kinase (MAPK) signaling, and the redox activity of Nrf2 were measured. To investigate the signaling mechanism involved in the shockwave treatment in chondrocytes, specific inhibitors of ROS, MAPK signaling, and Nrf2 activity were targeted. RESULTS: Shockwaves increased ECM synthesis without affecting cell viability or proliferation. Furthermore, they induced transient ROS production mainly through xanthine oxidase. The phosphorylation of ERK1/2 and p38 and the nuclear translocation of Nrf2 were activated by shockwaves. By contrast, suppression of ROS signaling mitigated shockwave-induced MAPK phosphorylation, Nrf2 nuclear translocation, and ECM synthesis. Pretreatment of chondrocytes with the specific inhibitors of MEK1/2 and p38, respectively, mitigated the shockwave-induced nuclear translocation of Nrf2 and ECM synthesis. Nrf2 inhibition by both small hairpin RNA knockdown and brusatol reduced the shockwave-enhanced ECM synthesis. CONCLUSIONS: Shockwaves activated Nrf2 activity through the induction of transient ROS signaling and subsequently enhanced ECM synthesis in chondrocytes. This study provided fundamental evidence confirming the potential of shockwaves for OA management.

Arecoline induces HA22T/VGH hepatoma cells to undergo anoikis - involvement of STAT3 and RhoA activation.

BACKGROUND: Our previous study showed that, in basal cell carcinoma cells, arecoline reduces levels of the tumor cell survival factor interleukin-6 (IL-6), increases levels of tumor suppressor factor p53, and elicits cell cycle arrest, followed by apoptosis. In preliminarily studies, we observed that arecoline induces detachment of the human-derived hepatoma cell line HA22T/VGH from the extracellular matrix. In the present study, we explored the fate of the detached HA22T/VGH cells and investigated the underlying mechanism. METHODS: HA22T/VGH cells or primary cultured rat hepatocytes were treated with arecoline, then changes in morphology, viability, apoptosis, and the expression of surface beta1-integrin, apoptosis-related proteins, and IL-6 were examined. Furthermore, activation of the signal transducer and activator of transcription 3 (STAT3) pathway and the RhoA/Rock signaling pathway, including p190RhoGAP and Src homology-2 domain-containing phosphatase SHP2, was examined. RESULTS: A low concentration of arecoline (

The envelope glycoprotein domain III of Dengue virus type 2 induced the expression of anticoagulant molecules in endothelial cells.

Dengue virus (DV) causes a non-specific febrile illness known as Dengue fever (DF), and a severe life-threatening illness, Dengue hemorrhagic fever/Dengue shock syndrome (DHF/DSS). Hemostatic changes induced by this virus involve three main factors: thrombocytopenia, endothelial cell damage, and significant abnormalities of the coagulation and fibrinolysis systems. The pathogenesis of bleeding in DV infections remains unknown. In this article, we focused on the DV activating endothelial cells and altering the parameters of hemostasis system. The expression of hemostasis-related factors, Thrombomodulin, TF, TFPI, t-PA, and PAI-1, in DV-infected cells were determined by RT-PCR. Flow cytometry analysis and immunofluorescence staining confirmed that the expression levels of TM in the DV-infected HMEC-1 and THP-1 cells were increased. In addition, the purified recombinant domain III of the envelope glycoprotein of DV (EIII) could induce the expression of TM in the HMEC-1 cells and THP-1 cells. The TM expression induced by DV or EIII in the endothelial cells and monocytic cells suggests that the EIII of DV plays an important role in the pathogenesis of DHF/DSS.

Effects of pulsed low-intensity ultrasound on human child chondrocytes.

The effect of pulsed low-intensity ultrasound (PLIUS) on human articular chondrocytes was evaluated in an in vitro 3-D agarose gel culture model. Chondrocytes isolated from young children's articular cartilage of ablated polydactylia were embedded in gel after expansion and exposed to PLIUS on the third day after embedding. Another group of cells was exposed to sham PLIUS as a control. Different intensities of PLIUS treatment-18 mW/cm(2), 48 mW/cm(2), 72 mW/cm(2) and 98 mW/cm(2) (1.0 MHz, with burst duration of 200 micros repeated at 1.0 kHz)-were administered for 20 min/d, and the medium was replaced twice a week. The cultures were evaluated for aggrecan synthesis by enzyme-linked immunosorbent assay (ELISA), type II collagen production by Western blotting or ELISA and cell proliferation by total DNA measurement. The PLIUS was found to increase aggrecan synthesis in a time-dependent manner. The maximal response was observed at an intensity of 48 mW/cm(2). After 14 d of exposure at this intensity, the aggrecan synthesis was 214 +/- 26% of control, and type II collagen synthesis was 148.5 +/- 8.0% of control. However, PLIUS treatment revealed no significant influence on cell proliferation, confirming that the stimulation of aggrecan and type II collagen synthesis by PLIUS was not the result of an increase in chondrocyte cell proliferation. In addition, it was found that human chondrocytes harvested from older donors become less responsive to PLIUS. From this in vitro 3-D study of cultured human chondrocytes, our findings suggest that PLIUS may be applied to the tissue engineering of cartilage constructs.

Anti-proliferative activity of biochanin A in human osteosarcoma cells via mitochondrial-involved apoptosis.

Biochanin A is a major isoflavone in red clover and a potent chemopreventive agent against cancer. However, the effects of biochanin A on human osteosarcoma cells have never been clarified. This study investigated the anti-proliferative potential of biochanin A in osteosarcoma cells. The results indicate that biochanin A inhibited cell growth and colony formation in a dose-dependent manner with a minimal toxicity to normal cells. The combination of doxorubicin and biochanin A could synergistically inhibit osteosarcoma cell growth. The cytotoxic effect of biochanin A via the induction of apoptosis as evidenced by formation of apoptotic bodies, externalization of phosphatidylserine, accumulation of sub-G1 phase cells, caspase 3 activation, and cleavage of PARP. Apoptosis was associated with loss of the mitochondrial membrane potential, release of cytochrome c, caspase 9 activation, increased Bax expression, and reduced Bcl-2 and Bcl-XL expression. Pre-treatment with a caspase-9 specific inhibitor (Z-LEHD-FMK) partially attenuated cell death, suggesting involvement of the intrinsic mitochondrial apoptotic cascade. However, pre-treatment with the JNK inhibitor SP600125, the MEK inhibitor PD-98059, and the p38 MAPK inhibitor SB203580 or the antioxidants vitamin E, N-acetylcysteine, and glutathione failed to prevent biochanin A-induced cell death. Our results suggest that biochanin A inhibits cell growth and induces apoptosis in osteosarcoma cells by triggering activation of the intrinsic mitochondrial pathway and caspase-9 and -3 and increasing the Bax: Bcl-2/Bcl-XL ratio.

Benzyl isothiocyanate promotes apoptosis of oral cancer cells via an acute redox stress-mediated DNA damage response.

Benzyl isothiocyanate (BITC) is a cruciferous vegetable-derived compound with anticancer properties in human cancer cells. However, its anticancer potential and underlying mechanisms remain absent in human oral cancer cells. Results indicate that BITC inhibits growth, promotes G2/M phase arrest and triggers apoptosis of OC2 cells with a minimal toxicity to normal cells. BITC-induced cell death was completely prevented by pretreatment with thiol-containing redox compounds including N-acetyl-l-cysteine (NAC), glutathione (GSH), dithiothreitol, and 2-mercaptoethanol, but not free radical scavengers mito-TEMPO, catalase, apocynin, l-NAME and mannitol. BITC rapidly produced reactive oxygen species and nitric oxide, triggered oxidative DNA damage. BITC effectively decreased the intracellular GSH and GSH/GSSG ratio and redox balance recovery by thiol-containing redox compounds, but not by free radical scavengers. Accordingly, redox stresses-DNA damage response (DDR) activated ATM, Chk2, p53, and p21 and subsequently resulted in G2/M phase arrest by inhibiting Cdc2 and cyclin B1. Notably, BITC-induced apoptosis was associated with reduced Mcl-1 and Bcl-2 expression, diminished mitochondrial membrane potential (ΔΨm), and increased PARP cleavage. These BITC-induced redox stress-mediated DDR and apoptosis could be blocked by NAC and GSH. Therefore, BITC can be a rational drug candidate for oral cancer and acted via a redox-dependent pathway.

The novel targets for anti-angiogenesis of genistein on human cancer cells.

Genistein has been reported to be a natural chemopreventive in several types of human cancer. In our prior study, soy isoflavones were shown to induce cell cycle arrest and apoptosis of bladder cancer cells in the range of human urine excretion. This study was designed to identify the novel molecular basis underlying anti-angiogenic activities of soy isoflavones. An immortalized E6 and five human bladder cancer cell lines were studied by immunoassay, flow cytometry, functional activity, reverse transcription-polymerase chain reaction, immunoblotting, and transwell co-culture in vitro. The efficacy of soy isoflavones on angiogenesis inhibition in vivo was examined by nude mice xenograft and chick chorioallantoic membrane bioassay. Factors analyzed included angiogenic factors, matrix-degrading enzymes, and angiogenesis inhibitors. Genistein was the most potent inhibitor of angiogenesis in vitro and in vivo among the isoflavone compounds tested. It may also account for most of the reduced microvessel density of xenografts observed and the suppressed endothelial migration by soy isoflavones. Genistein exhibited a dose-dependent inhibition of expression/excretion of vascular endothelial growth factor165, platelet-derived growth factor, tissue factor, urokinase plasminogen activator, and matrix metalloprotease-2 and 9, respectively. On the other hand, there was an up-regulation of angiogenesis inhibitors-plasminogen activator inhibitor-1, endostatin, angiostatin, and thrombospondin-1. In addition, a differential inhibitory effect between immortalized uroepithelial cells and most cancer cell lines was also observed. Altogether, we discovered that tissue factor, endostatin, and angiostatin are novel molecular targets of genistein. The current investigation provides further evidence in support of soy-based foods as natural dietary inhibitors of tumor angiogenesis.

Homocysteine at pathophysiologic concentrations activates human monocyte and induces cytokine expression and inhibits macrophage migration inhibitory factor expression.

OBJECTIVE: Homocystinemia is an important independent risk factor for atherosclerosis. Inflammatory cytokines play key roles in the development of atherogenesis. This study investigated the effect of homocysteine on inflammatory cytokine expression. METHODS: Human monocytes were treated in vitro with a variety of DL-homocysteine concentrations that ranged from physiologic concentration to higher than pathophysiologic concentration, and we analyzed their expressions of inflammatory cytokines, including tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, interleukin-8, interleukin-12, and migration inhibitory factor. RESULTS: DL-homocysteine at a marginal physiologic concentration of 2 microg/mL (15 microM) activated monocytes. In addition, DL-homocysteine at the pathophysiologic dose of 25 microg/mL (185 microM) induced mRNA and protein expressions of inflammatory cytokines tumor necrosis factor-alpha, IL-1beta, interleukin-6, interleukin-8, and interleukin-12. Moreover, at the larger dose of 50 microg/mL (370 microM) DL-homocysteine decreased expression of migration inhibitory factor at the mRNA and protein levels. CONCLUSION: These findings suggest that homocysteine may contribute to the initiation and progression of vascular disease by activating monocytes, resulting in the secretion of cytokines that amplify the inflammatory response.

Genistein arrests hepatoma cells at G2/M phase: involvement of ATM activation and upregulation of p21waf1/cip1 and Wee1.

Genistein, a soy isoflavone, has a wide range of biological actions that suggest it may be of use in cancer prevention. We have recently reported that it arrests hepatoma cells at G2/M phase and inhibits Cdc2 kinase activity. In the present study, we examined the signaling pathway by which genistein modulates Cdc2 kinase activity in HepG2 cells and leads to G2/M arrest, and found that it caused an increase in both Cdc2 phosphorylation and expression of the Cdc2-active kinase, Wee1. Genistein also enhanced the expression of the cell cycle inhibitor, p21waf1/cip1, which interacts with Cdc2. Furthermore, phosphorylation/inactivation of Cdc25C phosphatase, which dephosphorylates/activates Cdc2, was increased. Genistein enhanced the activity of the checkpoint kinase, Chk2, which phosphorylates/inactivates Cdc25C, induced accumulation of p53, and activated the ataxia-telangiectasia-mutated (ATM) gene. Caffeine, an ATM kinase inhibitor, inhibited these effects of genistein on Chk2, p53, and p21waf1/cip1. These findings suggest that the effect of genistein on G2/M arrest in HepG2 cells is partly due to ATM-dependent Chk2 activation, an increase in Cdc2 phosphorylation/inactivation as a result of induction of Wee1 expression, and a decrease in Cdc2 activity as a result of induction of p21waf1/cip1 expression.

Inducible nitric oxide synthase mediates MG132 lethality in leukemic cells through mitochondrial depolarization.

Proteasomes are highly expressed in rapidly growing neoplastic cells and essential for controlling the cell cycle process and mitochondrial homeostasis. Pharmacological inhibition of the proteasome shows a significant anticancer effect on hematopoietic malignancies that is usually associated with the generation of reactive oxygen species. In this study, we comprehensively investigated the role of endogenous oxidants in various cellular events of K562 leukemic cells in response to treatment with MG132, a proteasome inhibitor. MG132 at 1.4 µM potently triggered G2/M arrest, mitochondrial depolarization, and apoptosis. By such treatment, the protein level of inducible nitric oxide synthase (iNOS) was doubled and cellular oxidants, including nitric oxide, superoxide, and their derivatives, were increasingly produced. In MG132-treated cells, the increase in iNOS-derived oxidants was responsible for mitochondrial depolarization and caspase-dependent apoptosis, but was insignificant in G2/M arrest. The amount of iNOS was negatively correlated with that of manganese superoxide dismutase (MnSOD). Whereas iNOS activity was inhibited by aminoguanidine, cellular MnSOD levels as well as mitochondrial membrane potentials were upregulated, and consequentially G2/M arrest and apoptosis were thoroughly reversed. It is suggested that cells rich in functional mitochondria possess improved proteasome activity, which antagonizes the cytotoxic and cytostatic effects of MG132. In contrast to iNOS, endothelial NOS-driven cGMP-dependent signaling promoted mitochondrial function and survival of MG132-stressed cells. In conclusion, the functional interplay of proteasomes and mitochondria is crucial for leukemic cell growth, wherein iNOS plays a key role.

Phenethyl isothiocyanate induces DNA damage-associated G2/M arrest and subsequent apoptosis in oral cancer cells with varying p53 mutations.

Phenethyl isothiocyanate (PEITC) is a naturally occurring cruciferous vegetable-derived compound that inhibits cell growth and induces apoptosis in oral cancer cells. However, the exact mechanism of PEITC action has not been fully elucidated. This study investigated the molecular mechanism and anticancer potential of PEITC in oral squamous cell carcinoma (OSCC) cells with various p53 statuses. PEITC inhibited the growth of OC2, SCC4, and SCC25 cells (functional p53 mutants) in a dose-dependent manner with low toxicity to normal cells. Treatment with PEITC induced reactive oxygen species production, nitric oxide generation, and GSH depletion and triggered DNA damage response as evidenced by flow cytometry, 8-OHdG formation, and comet assay. Furthermore, the subsequent activation of ATM, Chk2, and p53 as well as the increased expression of downstream proteins p21 and Bax resulted in a G2/M phase arrest by inhibiting Cdc25C, Cdc2, and cyclin B1. The PEITC-induced apoptotic cell death, following a diminished mitochondrial transmembrane potential, reduced the expression of Bcl-2 and Mcl-1, released mitochondrial cytochrome c, and activated caspase 3 and PARP cleavage. The p53 inhibitor pifithrin-α and the antioxidants N-acetylcysteine and glutathione (GSH) protected the cells from PEITC-mediated apoptosis. However, mito-TEMPO, catalase, apocynin, and L-NAME did not prevent PEITC-induced cell death, suggesting that PEITC induced G2/M phase arrest and apoptosis in oral cancer cells via a GSH redox stress and oxidative DNA damage-induced ATM-Chk2-p53-related pathway. These results provide new insights into the critical roles of both GSH redox stress and p53 in the regulation of PEITC-induced G2/M cell cycle arrest and apoptosis in OSCCs.

The preventive effect of biochanin a on bone loss in ovariectomized rats: involvement in regulation of growth and activity of osteoblasts and osteoclasts.

Biochanin A (BCA) is a major isoflavone abundant in red clover (Trifolium pretense). The protective effect of BCA on bone loss in an ovariectomized (OVX) animal model has never been clarified. The objective of this study was to investigate the biological effects of BCA on bone loss in OVX rats in vivo and on the development of osteoblasts and osteoclasts in vitro. Ovariectomy resulted in a marked increase in body weight and a decrease in femoral bone mineral density and trabecular bone volume that was prevented by BCA or 17 ß -estradiol (E2) treatment. However, an increase in uterine weight was observed in E2-treated OVX rats, but not in response to BCA treatment. Treatment with BCA increased the mRNA expression of osterix, collagen type I, alkaline phosphatase (ALP), and osteocalcin and decreased the mRNA expression of tartrate-resistant acid phosphatase (TRAP) and the receptor activator of nuclear factor- κ B ligand (RANKL)/osteoprotegerin (OPG) ratio in the femur of OVX rats. Treatment with BCA or E2 prevented the OVX-induced increase in urinary deoxypyridinoline (DPD) and serum tumor necrosis factor α (TNF- α ) and interleukin-1 ß (IL-1 ß ). In vitro, BCA induced preosteoblasts to differentiate into osteoblasts and increased osteoblast mineralization. BCA inhibited preosteoclasts and osteoclast proliferation and decreased osteoclast bone resorption. These findings suggest that BCA treatment can effectively prevent the OVX-induced increase in bone loss and bone turnover possibly by increasing osteoblastic activities and decreasing osteoclastic activities.

Combined effect of soy isoflavones and vitamin D3 on bone loss in ovariectomized rats.

OBJECTIVE: Several studies have shown that soy isoflavones have estrogen-like activities and might constitute an alternative to hormone replacement treatment. The present study investigated the effects of soy isoflavones alone and combined with vitamin D3 on prevention of bone loss. METHODS: Sprague-Dawley rats were sham-operated (n = 8) or ovariectomized (OVX; n = 40), and then the OVX rats were randomly assigned to five groups that were untreated or treated for 14 wk with vitamin D3, 17ß-estradiol, soy isoflavone extract (SIE), or vitamin D3 plus SIE. The effects of the isoflavones and 1α,25(OH)(2)D(3) on cultured osteoblasts and osteoclasts also were investigated. RESULTS: In OVX rats, the bone mineral density and trabecular bone volume loss were improved by 17ß-estradiol, SIE, or SIE plus vitamin D3 treatment. SIE treatment was more effective than vitamin D3 or 17ß-estradiol in inhibiting increases in serum tumor necrosis factor-α levels and osteoblast osteoprotegerin expression. SIE plus vitamin D3 was more effective in increasing osterix expression than each alone. Bone cell cultures showed that the isoflavones induced preosteoblasts to differentiate into osteoblasts and increased osteoblast mineralization. Isoflavones inhibited preosteoclasts and osteoclast proliferation and decreased osteoclast resorption. The combination of isoflavones plus 1α,25(OH)(2)D(3) showed additive effects on the increase in cell proliferation of cultured preosteoblasts. CONCLUSION: Treatment with soy isoflavones might be an alternative to hormone replacement therapy in decreasing bone loss from postmenopausal estrogen deficiency. In addition, there are further effects on increasing transcription factor osterix expression and preosteoblast proliferation when these were combined with vitamin D3.

Caffeine inhibits adipogenic differentiation of primary adipose-derived stem cells and bone marrow stromal cells.

Caffeine consumption has been related to loss of body weight and modulates lipid metabolism. However, impacts of caffeine on adipogenic differentiation have not been well determined yet. The present study evaluated the effects of caffeine on adipogenesis using primary rat adipose-derived stem cells (ADSCs) and a mouse bone marrow stromal cell line (M2-10B4) in vitro. ADSCs and M2-10B4 were continuously exposed to caffeine (0.1-1mM) during adipogenic differentiation for 7 and 12 days, respectively. Oil red O and Nile red staining showed that caffeine reduced lipid droplet and adipocyte levels in both cell types. In addition, Nile red staining and FACScan flow cytometry showed that caffeine dose-dependently decreased adipocyte differentiation from 20% to 50% of the control ADSCs and M2-10B4 cells. Caffeine decreased the expression of adipogenesis-related genes including peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-α, adipocyte lipid binding protein, lipoprotein lipase, leptin, and TNFα in a dose-dependent manner. Rather, low concentration of caffeine (0.1mM) significantly increased IL-6 expression, but unexpectedly inhibited that at a concentration more than 0.3mM. Taken together, caffeine was able to effectively inhibit adipogenic differentiation of ADSCs and M2-10B4 cells partly through its inhibition of adipogenesis-related factors.

Biochanin a promotes osteogenic but inhibits adipogenic differentiation: evidence with primary adipose-derived stem cells.

Biochanin A has promising effects on bone formation in vivo, although the underlying mechanism remains unclear yet. This study therefore aimed to investigate whether biochanin A regulates osteogenic and adipogenic differentiation using primary adipose-derived stem cells. The effects of biochanin A (at a physiologically relevant concentration of 0.1-1 µM) were assessed in vitro using various approaches, including Oil red O staining, Nile red staining, alizarin red S staining, alkaline phosphatase (ALP) activity, flow cytometry, RT-PCR, and western blotting. The results showed that biochanin A significantly suppressed adipocyte differentiation, as demonstrated by the inhibition of cytoplasmic lipid droplet accumulation, along with the inhibition of peroxisome proliferator-activated receptor gamma (PPAR γ ), lipoprotein lipase (LPL), and leptin and osteopontin (OPN) mRNA expression, in a dose-dependent manner. On the other hand, treatment of cells with 0.3 µM biochanin A increased the mineralization and ALP activity, and stimulated the expression of the osteogenic marker genes ALP and osteocalcin (OCN). Furthermore, biochanin A induced the expression of runt-related transcription factor 2 (Runx2), osteoprotegerin (OPG), and Ras homolog gene family, member A (RhoA) proteins. These observations suggest that biochanin A prevents adipogenesis, enhances osteoblast differentiation in mesenchymal stem cells, and has beneficial regulatory effects in bone formation.