Tag Archives: in vitro

Ellagic Acid from Raspberries Inhibits Bone Resorption in Rats

Abstract

Anti-inflammatory Effects of Polyphenolic-Enriched Red Raspberry Extract in an Antigen-Induced Arthritis Rat Model.

The red raspberry ( Rubus idaeus ) fruit contains bioactive polyphenols including anthocyanins and ellagitannins with reported anti-inflammatory properties. This study sought to investigate the cartilage-protecting and anti-inflammatory effects of a polyphenolic-enriched red raspberry extract (RRE; standardized to total polyphenol, anthocyanin, and ellagitannin contents) using (1) an in vitro bovine nasal explant cell culture model and (2) an in vivo adjuvant-induced arthritis rat model. RRE contained 20% total polyphenols (as gallic acid equivalents), 5% anthocyanins (as cyanidin-3-glucoside equivalents), and 9.25% ellagitannins (as ellagic acid equivalents). In the in vitro studies, bovine nasal explants were stimulated with 10 ng/mL IL-1β to induce the release of proteoglycan and type II collagen. On treatment with RRE (50 μg/mL), there was a decrease in the rate of degradation of both proteoglycan and type II collagen. In the in vivo antigen-induced arthritis rat model, animals were gavaged daily with RRE (at doses of 30 and 120 mg/kg, respectively) for 30 days after adjuvant injection (750 μg of Mycobacterium tuberculosis suspension in squalene). At the higher dose, animals treated with RRE had a lower incidence and severity of arthritis compared to control animals. Also, histological analyses revealed significant inhibition of inflammation, pannus formation, cartilage damage, and bone resorption by RRE. This study suggests that red raspberry polyphenols may afford cartilage protection and/or modulate the onset and severity of arthritis.

Jean-Gilles D, Li L, Ma H, Yuan T…
J. Agric. Food Chem. Dec 2011
PMID: 22111586

Furosin Suppresses Osteoclasts in Mouse Cells

Abstract

Furosin, an ellagitannin, suppresses RANKL-induced osteoclast differentiation and function through inhibition of MAP kinase activation and actin ring formation.

Phenolic compounds including tannins and flavonoids have been implicated in suppression of osteoclast differentiation/function and prevention of bone diseases. However, the effects of hydrolysable tannins on bone metabolism remain to be elucidated. In this study, we found that furosin, a hydrolysable tannin, markedly decreased the differentiation of both murine bone marrow mononuclear cells and Raw264.7 cells into osteoclasts, as revealed by the reduced number of tartrate resistant acid phosphatase (TRAP)-positive multinucleated cells and decreased TRAP activity. Furosin appears to target at the early stage of osteoclastic differentiation while having no cytotoxic effect on osteoclast precursors. Analysis of the inhibitory mechanisms of furosin revealed that it inhibited the receptor activator of nuclear factor-kappaB ligand (RANKL)-induced activation of p38 mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase (JNK)/activating protein-1 (AP-1). Furthermore, furosin reduced resorption pit formation in osteoclasts, which was accompanied by disruption of the actin rings. Taken together, these results demonstrate that naturally occurring furosin has an inhibitory activity on both osteoclast differentiation and function through mechanisms involving inhibition of the RANKL-induced p38MAPK and JNK/AP-1 activation as well as actin ring formation.

Park EK, Kim MS, Lee SH, Kim KH…
Biochem. Biophys. Res. Commun. Dec 2004
PMID: 15555594

Ellagic Acid May Be a Natural SERM

Abstract

Evaluation of estrogenic/antiestrogenic activity of ellagic acid via the estrogen receptor subtypes ERalpha and ERbeta.

Ellagic acid is a plant-derived polyphenol, possessing antioxidant, antiproliferative, and antiatherogenic properties. Whether this compound has estrogenic/antiestrogenic activity, however, remains largely unknown. To answer this question, we first investigated the ability of ellagic acid to influence the activity of the estrogen receptor subtypes ERalpha and ERbeta in HeLa cells. Cells co-transfected with an estrogen response element (ERE)-driven luciferase (Luc) reporter gene and an ERalpha- or ERbeta-expression vector were exposed to graded concentrations of ellagic acid. At low concentrations (10(-7) to 10(-9) M), this compound displayed a small but significant estrogenic activity via ERalpha, whereas it was a complete estrogen antagonist via ERbeta. Further evaluation revealed that ellagic acid was a potent antiestrogen in MCF-7 breast cancer-derived cells, increasing, like the pure estrogen antagonist ICI182780, IGFBP-3 levels. Moreover, ellagic acid induced nodule mineralization in an osteoblastic cell line (KS483), an effect that was abolished by the estrogen antagonist. Endometrium-derived epithelial cells (Ishikawa) showed no response to the natural compound by using a cell viability assay (MTT). These findings suggest that ellagic acid may be a natural selective estrogen receptor modulator (SERM).

Papoutsi Z, Kassi E, Tsiapara A, Fokialakis N…
J. Agric. Food Chem. Oct 2005
PMID: 16190622

Creatine May Stimulate Bone Repair in Rats

Abstract

Stimulatory effects of creatine on metabolic activity, differentiation and mineralization of primary osteoblast-like cells in monolayer and micromass cell cultures.

The effects of creatine (Cr) supplementation on primary rat osteoblast-like cells cultured as monolayer and micromass were investigated. Cr was added to the medium at concentrations of either 10 or 20 mM. At various time points, the cell cultures were analyzed morphologically, metabolically and biochemically. The degree of differentiation of primary osteoblast-like cell cultures was higher in micromass cultures compared to monolayer cultures, as judged by alkaline phosphatase (ALP) activity and extent of mineralization. In both culture systems, Cr supplementation showed positive effects, which were dependent on the organizational level of the osteoblast-like cells in such a way that the cells in monolayer culture showed significantly increased metabolic activity, ALP activity and mineralization in the presence of Cr than without the supplement. In micromass cultures, Cr also significantly enhanced ALP activity and mineralization, without affecting metabolic activity. The effect of Cr on ALP activity was more pronounced at higher concentrations of Cr, but 20 mM Cr already showed some adverse effects on cell viability. In conclusion, chemically pure Cr added to low serum cell culture medium has a stimulatory effect on metabolic activity, differentiation and mineralization of osteoblast-like cells indicating that Cr supplementation could also be used as a potential clinical intervention to stimulate cell growth, differentiation and mineralization during bone repair in vivo.

Gerber I, ap Gwynn I, Alini M, Wallimann T
Eur Cell Mater 2005
PMID: 16025431 | Free Full Text

Pomegranate Enhances Bone Formation in Mice

Abstract

Effects of pomegranate extracts on cartilage, bone and mesenchymal cells of mouse fetuses.

Pomegranate is a rich source of polyphenols, which are believed to be responsible for the oestrogenic activities of extracts of this fruit in mice. One of these potential activities is the prevention of bone loss. The objectives of the present study were to determine the effects of pomegranate extract on chondrogenesis and osteogenesis in mouse embryos in vivo and limb bud cultures in vitro. A total of fifty pregnant Balb/c mice were given vehicle, pomegranate juice extract (PJE), pomegranate husk extract (PHE) or a mixture of husk and juice extract (PME). Their embryos were stained with alizarin red S and alcian blue, and the length of the femur, tibia and their ossification zones were measured on day 19 of gestation. Bone Ca content in pregnant mice was also measured. Mice treated with PJE showed an increase in bone Ca content. Dietary supplementation with all extracts significantly increased embryo femur length and osteogenesis index. Mesenchymal cells from fetal limb buds were cultured and exposed to 10, 100, 1000 and 10 000 μg/ml of PJE, PHE or PME. The number of viable cells was greater in cultures exposed to the extracts than in control cultures. The number of cartilage nodules and their diameters were greater in extract-treated cell cultures, a finding which reflected increased cell proliferation and differentiation rates. In conclusion, the findings of the present study suggest that pomegranate is able to enhance bone formation.

Monsefi M, Parvin F, Talaei-Khozani T
Br. J. Nutr. Mar 2012
PMID: 21781378

Pomegranate Stimulates Mouse Osteoblast Cells

Abstract

Stimulation of osteoblastic differentiation and inhibition of interleukin-6 and nitric oxide in MC3T3-E1 cells by pomegranate ethanol extract.

In this experiment, we studied the effects of pomegranate fruit extract (PE) on the function of osteoblastic MC3T3-E1 cells and the production of local factors in osteoblasts. PE (16 approximately 250 microg/ml) significantly increased the growth of MC3T3-E1 cells (P < 0.05). Moreover, PE (50 microg/ml) caused a significant elevation of alkaline phosphatase (ALP) activity and collagen content in the cells. We then examined the effect of PE on the TNF-alpha-induced production of interleukin-6 (IL-6) and nitric oxide (NO) in osteoblasts. Treatment with PE (10 approximately 50 microg/ml) decreased the TNF-alpha (10(-10) M)-induced production of IL-6 and NO in osteoblasts.

Kim YH, Choi EM
Phytother Res May 2009
PMID: 19107859

Cissus May Increase Local IGF-1 in Osteoblasts

Abstract

Cissus quadrangularis augments IGF system components in human osteoblast like SaOS-2 cells.

Osteoporosis is a public health problem which is associated with significant morbidity and mortality. Growth factors are produced locally in the bone and control cellular events such as induction of bone growth. Signaling through the Insulin-like growth factor (IGF)-I receptor (IGF-IR) by locally synthesized IGF-I or IGF-II in osteoblast is considered crucial for normal development and for bone remodeling. Traditional use of Cissus quadrangularis (C. quadrangularis) in the treatment of bone disorders have been documented, however its regulatory effects on IGF system components remain largely unknown. The present study is employed to delineate the effects of ethanolic extract of C. quadrangularis on the regulation of IGF system components in human osteoblast like SaOS-2 cells. RT-PCR analysis revealed an increase in the mRNA expression of IGF-I, IGF-II, IGF-IR in cells treated with C. quadrangularis when compared with control cells. The mRNA expression of IGF binding protein-3 (IGFBP-3) did not differ significantly between control and C. quadrangularis treated cells. Immunoradiometric analysis revealed increased levels of IGF-I, IGF-II and IGFBP-3 in the conditioned medium of C. quadrangularis treated cultures when compared with control. Western blotting analysis revealed increase in protein levels of IGF-IR in cells treated with C. quadrangularis. These results indicate positive regulation of C. quadrangularis on the IGF system components of human osteoblast like SaOS-2 cells.

Muthusami S, Ramachandran I, Krishnamoorthy S, Govindan R…
Growth Horm. IGF Res. Dec 2011
PMID: 22015109

Cissus Anabolic Actions on Bone Cells

Abstract

Effects of Cissus quadrangularis on the proliferation, differentiation and matrix mineralization of human osteoblast like SaOS-2 cells.

Osteoporosis is a public health problem which is associated with significant morbidity and mortality. The repair of bone defect is still a big challenge for orthopedic surgeons. Traditional use of Cissus quadrangularis (C. quadrangularis) in the treatment of bone disorders has been documented. The present study was employed to delineate the effects of ethanolic extract of C. quadrangularis on the proliferation, differentiation and matrix mineralization of human osteoblast like SaOS-2 cells. Lactate dehydrogenase assayed in the conditioned medium of control and C. quadrangularis treated cells did not differ significantly indicating that ethanolic extract of C. quadrangularis is nontoxic to osteoblastic cells. [(3)H] Thymidine incorporation assay revealed that C. quadrangularis treatment has increased the DNA synthesis of human osteoblastic SaOS-2 cells indicating increased proliferation of these cells. The data on alizarin red and ALP staining revealed increased matrix mineralization of human osteoblast like SaOS-2 cells. The study also revealed that the anabolic actions of ethanolic extract of C. quadrangularis in human osteoblast like cells are mediated through increased mRNA and protein expression of Runx2, a key transcription factor involved in the regulation of bone matrix proteins. Chromatin immunoprecipitation analysis revealed increased transcriptional activity of Runx2 on the promoter of osteocalcin after C. quadrangularis treatment. These results indicate positive regulation of C. quadrangularis on the proliferation, differentiation, and matrix mineralization of human osteoblast like SaOS-2 cells.

Muthusami S, Senthilkumar K, Vignesh C, Ilangovan R…
J. Cell. Biochem. Apr 2011
PMID: 21308732

Cissus, Vitex, and Allophylus May Increase Osteoblasts

Abstract

Anti-osteoporotic constituents from Indian medicinal plants.

The objective of this study was to determine the in vitro osteogenic activities of selected medicinal plants used traditionally in India. The compounds isolated from three plants viz. Allophylus serratus, Cissus quadrangularis and Vitex negundo were evaluated for their in vitro osteogenic activities. Primary cultures of osteoblasts were used to determine the effects of these components on osteoblast functions. Five of the fourteen compounds isolated led to increase in osteoblast differentiation and mineralization. These findings lend support to the use of Allophylus serratus, Cissus quadrangularis and Vitex negundo in traditional medicine.

Kumar M, Rawat P, Dixit P, Mishra D…
Phytomedicine Nov 2010
PMID: 20554183

Cissus Stimulates Osteoblastogenesis in Rats

Abstract

Petroleum ether extract of Cissus quadrangularis (Linn.) enhances bone marrow mesenchymal stem cell proliferation and facilitates osteoblastogenesis.

To evaluate the effects of the petroleum ether extract of Cissus quadrangularis on the proliferation rate of bone marrow mesenchymal stem cells, the differentiation of marrow mesenchymal stem cells into osteoblasts (osteoblastogenesis) and extracellular matrix calcification. This study also aimed to determine the additive effect of osteogenic media and Cissus quadrangularis on proliferation, differentiation and calcification.
MSCs were cultured in media with or without Cissus quadrangularis for 4 weeks and were then stained for alkaline phosphatase. Extracellular matrix calcification was confirmed by Von Kossa staining. marrow mesenchymal stem cells cultures in control media and osteogenic media supplemented with Cissus quadrangularis extract (100, 200, 300 microg/mL) were also subjected to a cell proliferation assay (MTT).
Treatment with 100, 200 or 300 microg/mL petroleum ether extract of Cissus quadrangularis enhanced the differentiation of marrow mesenchymal stem cells into ALP-positive osteoblasts and increased extracellular matrix calcification. Treatment with 300 microg/mL petroleum ether extract of Cissus quadrangularis also enhanced the proliferation rate of the marrow mesenchymal stem cells. Cells grown in osteogenic media containing Cissus quadrangularis exhibited higher proliferation, differentiation and calcification rates than did control cells.
The results suggest that Cissus quadrangularis stimulates osteoblastogenesis and can be used as preventive/ alternative natural medicine for bone diseases such as osteoporosis.

Potu BK, Bhat KM, Rao MS, Nampurath GK…
Clinics (Sao Paulo) 2009
PMID: 19841707 | Free Full Text