Tag Archives: in vitro

Cissus May Increase Osteoblasts via MAPK

Abstract

Cissus quadrangularis extract enhances biomineralization through up-regulation of MAPK-dependent alkaline phosphatase activity in osteoblasts.

Cissus quadrangularis Linn. has been implicated as therapeutic agent for enhancing bone healing. Though its osteogenic activity has been suggested, the underlying mechanism still remains unclear. In the present study, the effects of ethanol extract of C. quadrangularis (CQ-E) on osteoblast differentiation and function were analyzed using murine osteoblastic cells. The results indicated that mRNA expressions of osteoblast-related genes were not affected by the CQ-E treatment. However, alkaline phosphatase (ALP) activity and the extent of mineralized nodules were significantly increased in treated cells compared with controls. The addition of an extracellular regulated kinase 1/2 inhibitor, a Jun N-terminal kinase 1/2/3 inhibitor and a p38 mitogen-activated protein kinase (MAPK) inhibitor resulted in significantly decreased ALP activity, preferentially by p38 MAPK inhibitor. These results suggested that CQ-E may regulate osteoblastic activity by enhancing ALP activity and mineralization process, and the increased ALP activity effect of CQ-E is likely mediated by MAPK-dependent pathway.

Parisuthiman D, Singhatanadgit W, Dechatiwongse T, Koontongkaew S
In Vitro Cell. Dev. Biol. Anim.
PMID: 19057968

Oleuropein (from Olives) Increases Osteoblasts In Vitro

Abstract

Oleuropein enhances osteoblastogenesis and inhibits adipogenesis: the effect on differentiation in stem cells derived from bone marrow.

The effects of oleuropein on the processes of osteoblastogenesis and adipogenesis in mesenchymal stem cells (MSCs) from human bone marrow have been studied. We report that oleuropein, a polyphenol abundant in olive tree products, reduces the expression of peroxisome proliferator-activated receptor gamma (PPARγ), inhibits adipocyte differentiation, and enhances differentiation into osteoblast.
Age-related bone loss is associated with osteoblast insufficiency during continuous bone remodeling. It has been suggested that the formation of osteoblasts in bone marrow is closely associated with adipogenesis, and age-related changes in this relationship could be responsible for the progressive adiposity of bone marrow which occurs with osteoporosis. In addition, the consumption of oleuropein, a major polyphenol in olive leaves and olive oil, has been associated with a reduction in bone loss.
We have analyzed the effects of oleuropein-at concentrations between 10(-6) and 10(-4) M-on the processes of osteoblastogenesis and adipogenesis in MSCs from human bone marrow.
The results show an increase in osteoblast differentiation and a decrease in adipocyte differentiation when there is oleuropein in the culture media. The gene expression of osteoblastogenesis markers, RUNXII, osterix, collagen type I, osteocalcin, or alkaline phosphatase (ALP), was higher in osteoblast-induced oleuropein-treated cells. Also, the ALP activity and extracellular matrix mineralization were higher when oleuropein was present in the media. Oleuropein in MSCs induced adipocytes to produce a decrease in the expression of the genes involved in adipogenesis, the PPARγ, lipoprotein lipase, or fatty acid-binding protein 4, and minor fat accumulation.
Our data suggest that oleuropein, highly abundant in olive tree products included in the traditional Mediterranean diet, could prevent age-related bone loss and osteoporosis.

Santiago-Mora R, Casado-Díaz A, De Castro MD, Quesada-Gómez JM
Osteoporos Int Feb 2011
PMID: 20495905