Mechanics rules cell biology

Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction

Indirect co-culture with tenocytes promotes proliferation and mRNA expression of tendon/ligament related genes in rat bone marrow mesenchymal stem cells

Recent evidences have suggested that humoral factors released from the appropriate co-cultured cells influenced the expansion and differentiation of mesenchymal stem cells (MSCs). However, little is known about the proliferation and differentiation of MSCs subjected to co-culture condition with tenocytes. In this study, we aimed to establish a co-culture system of MSCs and tenocytes and investigate the proliferation and tendon/ligament related gene expression of MSCs. MTT assay was used to detect the expansion of MSCs. Semi-quantitative RT-PCR was performed to investigate the expression of proliferation associated c-fos gene and tendon/ligament related genes, including type I collagen (Col I), type III collagen (Col III), tenascin C and scleraxis. Significant increase in MSCs expansion was observed after 3 days of co-culture with tenocytes. The c-fos gene expression was found distinctly higher than for control group on day 4 and day 7 of co-culture. The mRNA expression of four tendon/ligament related genes was significantly up-regulated after 14 days of co-culture with tenocytes. Thus, our research indicates that indirect co-culture with tenocytes promotes the proliferation and mRNA expression of tendon/ligament related genes in MSCs, which suggests a directed differentiation of MSCs into tendon/ligament

Structural properties of protein and their role in polymer nanocomposites

The growing concern over the environment raises the question of\u3cbr/\u3ebiodegradability and renewability in numerous fields, including materials and\u3cbr/\u3eenergy. Therefore, industries and researchers focus more on the development of biomaterials generated from natural sources. In this context, proteins and their unique properties made them ideal candidates to be used in different novel applications and are not limited to films, hydrogels, biological tissue engineering, and polymer composites. In this chapter, authors highlight the different sources of protein and their structural properties. Then, the extraction methods are discussed in detail. Further, the different processing methods to prepare the protein-based composites were explained. In overall, this chapter aims to highlight the recent developments of protein-based materials in different fields, based on the literature