Free fatty acid receptor 2 Free fatty acid receptor 2 Free fatty acid receptor 2 (FFAR2) is a G-protein coupled receptor encoded by the FFAR2 gene. FFAR2 mRNA is expressed in adipose tissue, pancreas, spleen, lymph nodes, bone marrow, and peripheral blood mononuclear cells. FFAR2 transcription is regulated by the XBP1 transcription factor which binds to the core promoter. Mouse studies utilizing Ffar2 gene deletions have implicated the receptor in the regulation of energy metabolism and immune responses. Short Chain Fatty Acids (SCFA's) generated in the processing of fiber by intestinal microbiota act as ligands for the receptor and can affect neutrophil chemotaxis. However, discrepancies
Soft tissue Normally the soft tissue is very hydrated because of the ground substance. The fibroblasts are the most common cell responsible for the production of soft tissues' fibers and ground substance. Variations of fibroblasts, like chondroblasts, may also produce these substances. At small strains, elastin confers stiffness to the tissue and stores most of the strain energy. The collagen fibers are comparatively inextensible and are usually loose (wavy, crimped). With increasing tissue deformation the collagen is gradually stretched in the direction of deformation. When taut, these fibers produce a strong growth in tissue stiffness. The composite behavior is analogous to a