The expression profile of angiogenic genes in critical limb ischemia popliteal arteries.

Critical limb ischemia (CLI) represents the most severe form of peripheral arterial disease (PAD) and is the leading cause of non-traumatic amputations in western populations. In recent years, therapeutic angiogenesis has been considered to be a potential treatment option for CLI patients, however the molecular mechanism of ischemia-induced vascularization is still not fully understood. The identification of genetic factors underlying vascular responses to ischemia will improve our understanding of the biological causes of the disease and enhance personalized therapies in the future. In this work, we determined, for the first time, the expression profile of angiogenesis-related genes utilizing unique human material: the popliteal arteries retrieved during lower limb amputation from patients with CLI. Using custom-designed TaqMan Low-Density Array (TLDA) cards we investigated the mRNA level of 90 genes on CLI samples compared to healthy donors. We identified three significantly up-regulated genes in CLI group: matrix metalloproteinase 9 (MMP-9), VE-cadherin (CDH5) and integrin alpha 4 (ITGA4). However, among all investigated genes, only lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1) was significantly reduced. In order to verify whether hypoxic conditions occur in popliteal arteries of CLI patients, we validated the transcription level of selected proangiogenic genes by real-time PCR on a larger number of samples. These results showed that the expression of key genes involved in angiogenesis, such as MMP9, HGF, HIF1A, VEGF-A and FLT1 were elevated in patients with CLI. Moreover, the study revealed that the expression of VEGF-A and FLT1 was associated with activation of HIF1A transcription. In conclusion, our data revealed the alteration in the mRNA level of genes involved in matrix remodelling, cell-cell adhesion as well as endothelial cell migration and proliferation in human popliteal arteries.

Elevated expression of runt-related transcription factors in human abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) is a multifactorial disease of unknown etiology. AAA is caused by segmental weakening of the aortic walls and progressive aortic dilation leading to the eventual rupture of the aorta, accompanied by intense inflammation. Additionally, studies have indicated a close relationship between the pathogenesis and progression of AAA and cellular immune responses in aneurysm wall tissue. The Runt-related genes (RUNX) encode multifunctional mediators of the of intracellular signal transduction pathways in vascular remodeling, endothelial function, immune response and inflammation. The aim of this study was to evaluate the expression level of RUNX regulatory genes in AAA tissues and to assess the correlations between them. The study was performed on AAA wall-tissue samples obtained from patients with AAA during open aneurysm repair and normal aortic tissues collected from healthy organ donors. There are no proven clinical management strategies or pharmaco-therapeutics to prevent AAA progression once an AAA has been detected. Moreover, so far no biomarkers have been established to indicate the disease status of AAA. Hence, understanding the pathogenesis of AAA has recently become an increasing priority in basic and translational vascular research. We identified significantly higher mRNA and protein level of all of three Runt-related genes in aneurysmal aorta compared to a normal aorta. Increased expression of RUNX2 was demonstrated for the first time in abdominal aortic aneurysm tissue. Additionally, relationships between the activity of RUNX genes in the pathological tissue were identified. The results of elevated expression of RUNX genes and their relationships in the AAA tissues suggest the involvement of conserved Runt-related genes in the pathophysiology of AAA development.

Differential effect of IFN-tau on proliferation and distribution of lymphocyte subsets in one-way mixed lymphocyte reaction in cows and heifers.

IFN-tau is a signaling protein secreted by the bovine conceptus during the peri-implantation period and responsible for pregnancy recognition. Its main role is the prevention of pulsatile release of luteolytic PGF2alpha, but it also exerts immunomodulatory activities characteristic for other type I interferons. The aim of the study was to examine the effect of IFN-tau on the proliferation and distribution of peripheral blood lymphocyte subsets during one-way mixed lymphocyte reaction (MLR) in cows and heifers. IFN-tau inhibited the proliferative response of lymphocytes in MLR both in cows and heifers in a dose-dependent manner, but cow lymphocytes were less susceptible than those ones from heifers. It was also showed that IFN-tau differentially changed lymphocyte subsets distribution in MLR in cows and heifers. In cows, the relative percentage of CD8(+) cells after MRL in the presence of IFN-tau was significantly lower than in heifers. Differential effect of rIFN-tau on proliferation and lymphocyte subsets distribution in a one-way MRL in cows and heifers indicated that the age of the mother is an important factor in immunomodulatory effect towards developing bovine embryo.

Surface charge and the association of liposomes with colon carcinoma cells.

Interaction between the plasma membrane and aggregate lipid surface determines how efficiently the encapsulated drug will be delivered into the cell. Electrostatic interactions are one of the main forces affecting liposome and aggregate association with the charged cell surface. In this study, the effect of surface charge on the association of liposomes with human colon CX-1.1 cancer cells was studied. When phosphatidylserine was incorporated into a lipid bilayer, the amount of liposomes associated with cells tended to increase along with the amount of negatively charged lipid present in the liposomal lipid bilayer. When the cationic lipid dioleoyl-1,2-diacyl-3-trimethylammonium-propane (DOTAP) was included into the liposome formula, their uptake by the cells was also increased. Maximum binding occurred when the amount of positively charged lipids in liposomes was about 10 mol% of lipids.