Heparin and the phenotype of adult human vascular smooth muscle cells

NF-kB affects migration of vascular smooth muscle cells after treatment with heparin and ibrutinib

The migration of vascular smooth muscle cells (VSMCs) is one of the most important events in the remodeling of atherosclerosis plaque. The aim of study was to investigate the role of Heparin in the VSMC migration and its association with the NF-kB, collagen 1 and collagen 3 expression levels. Moreover, the incorporation of Heparin was studied in the VSMC cultures including Betulinic acid and Ibrutinib. Twelve cell groups were cultured and treated with the Heparin, Betulinic acid and Ibrutinib based on the viability and toxicity in 24-h and 48-h periods. The gene and protein expression levels were measured by RT-qPCR and western blotting techniques. The VSMC migration was determined by scratch test. In contrast with Ibrutinib (2 μM), Heparin (30 IU) increased significantly (P < 0.05) the NF-kB gene and protein expression levels and the VSMC migration during the exposure periods. Heparin (15 IU and 30 IU) also increased the collagen 1 gene expression level in the 48-h period while Heparin (5 IU and 15 IU) increased the collagen 3 gene expression levels in both periods. Incorporating Heparin into the cultures including Betulinic acid and Ibrutinib affected the collagen 1 and collagen 3 expression levels. The data suggested that the cell migration relates to NF-kB in the VSMCs treated with Heparin and Ibrutinib. Furthermore, the Heparin doses (5 IU and 15 IU) were safe for VSMCs based on the NF-kB, and collagen 3 expression levels.

LPP, a LIM protein highly expressed in smooth muscle

An 80-kDa protein, prominently expressed in smooth muscle, was microsequenced and identified as LPP, the product of the lipoma-preferred partner gene (Petit MMR, Mols R, Schoenmakers EFPM, Mandahl N, and Van de Ven WJM. Genomics 36: 118-129, 1996). Using a specific anti-LPP antibody, we showed, in Western blots and with immunofluorescence microscopy, the selective expression of LPP in vascular and visceral smooth muscles (approximately 0.5-1 ng/microg total protein). In other mature (noncultured) tissues, including heart and skeletal muscle, the protein is present only in trace amounts and is closely correlated with the levels of the smooth muscle marker alpha-actin. In freshly isolated guinea pig bladder smooth muscle cells, immunofluorescence images showed LPP as linear arrays of punctate, longitudinally oriented staining superimposed with vinculin staining on the plasma membrane surface. A corresponding pattern of periodic labeling at the membrane in transverse sections of bladder smooth muscle suggested an association of LPP with peripheral dense bodies. In cultured rat aortic smooth muscle cells, LPP colocalized with vinculin at focal adhesions but not with p120 catenin or alpha-actinin. Overexpression of the protein increased EGF-stimulated migration of vascular smooth muscle cells in Transwell assays, suggesting the participation of LPP in cell motility. The Rho-kinase inhibitor Y-27632 dissociated focal adhesions and LPP staining at the cell periphery and enhanced the nuclear accumulation of LPP induced by leptomycin B, indicating that LPP has a potential for relocating to the nucleus through a shuttling mechanism that is sensitive to inhibition of Rho-kinase.

Stimulation of human colonic epithelial cells by leukemia inhibitory factor is dependent on collagen-embedded fibroblasts in organotypic culture

The colonic epithelium undergoes a continuous cycle of proliferation, differentiation, and apoptosis. To characterize factors important for colonic homeostasis and its dysregulation, human fetal colonic epithelial cells were isolated and seeded on a collagen type I matrix with embedded colonic fibroblasts. The epithelial cells rapidly spread from clusters and proliferated, and within 3 days, a columnar layer of polarized epithelium surrounded the surface of the constricted collagen matrix. The polarized enterocytes developed brush borders, tight junctions and desmosomes, and goblet and enteroendocrine cells were present. A balance of growth and differentiation was maintained for several weeks in the presence of collagen-embedded fibroblasts and a complex mixture of growth factors. Leukemia inhibitory factor (LIF) was critical for proliferation of enterocytes and inhibited expression of the differentiation marker carbonic anhydrase II. In the presence of LIF, the relative number of goblet cells remained stable, whereas enteroendocrine relative cell number declined. LIF-stimulated epithelial cells remained dependent on the presence of fibroblasts in the matrix. In combination with stem cell factor and endothelin 3, LIF induced formation of disorganized structures of stratified and semi-stratified cells, suggesting that the homeostatic balance in the normal human colon requires cooperation with differentiation-inducing factors.

Heparin/endothelial cell growth supplement regulates matrix gene expression and prolongs life span of vascular smooth muscle cells through modulation of interleukin-1

Vascular smooth muscle cells produce and respond to interleukin-1, a cytokine which modifies inflammation-associated vascular activities including the synthesis of extracellular matrix proteins. We have established vascular smooth muscle cells culture conditions in which heparin, in the presence of endothelial cell growth supplement, promotes cell proliferation and inhibits interleukin-1 and matrix protein expression. To test whether interleukin-1 mediates growth and matrix modulation by heparin/endothelial cell growth supplement, vascular smooth muscle cells were transfected with an Epstein-Barr virus-derived expression vector designed to express interleukin-1 antisense transcripts. RNase protection and ELISA assays demonstrated a complete block of interleukin-1 transcription and protein synthesis. Northern blot analysis also showed that interleukin-1 antisense decreased the expression of matrix genes such as type I collagen, fibronectin, and decorin similar to downregulation after heparin/endothelial cell growth supplement treatment. In contrast, the expression of versican was not affected, indicating a selective suppression of matrix proteins. In addition, interleukin-1 antisense significantly prolonged the life span of vascular smooth muscle cells in culture. Our data suggest that heparin/endothelial cell growth supplement induces matrix remodeling and controls growth and senescence of vascular smooth muscle cells through down-regulation of interleukin-1.