Laminin isoforms in atherosclerotic arteries from mice and man
Uwe Rauch1, Amit Saxena1, Stefan Lorkowski2, Jürgen Rauterberg3, Harry Björkbacka4, Madeleine Durbeej1 and Anna Hultgårdh-Nilsson1
1Institute of Experimental Medical Sciences, Lunds University, Lund, Sweden, 2Institute of Nutrition, Friedrich Schiller University, Jena, Germany, 3Leibniz Institute of Arteriosclerosis Research, Münster, Germany, and 4Institute of Clinical Science, Lunds University, Malmö, Sweden.
Offprint requests to: Dr. Uwe Rauch, Institute of Experimental Medical Sciences, Lunds University, MBC B12, 22184 Lund, Sweden. e-mail: uwe.rauch@med.lu.se
Summary. The properties of the arterial vasculature depend to a large extent on the activities of smooth muscle cells, which, in turn, are determined by their extracellular environment. During pathological conditions, such as atherosclerosis, this interaction is altered. In close proximity to medial smooth muscle cells are basement membrane components, such as different isoforms of laminin. These proteins can have great impact on cellular function via interaction with cell surface integrins. However, knowledge of laminins in smooth muscle cell basement membranes during normal and pathological conditions is scarce.
Therefore, we have analyzed the presence of laminin isoforms in atherosclerotic lesions of apolipoprotein E (ApoE)-deficient mice. Our study revealed that the laminin chain isotype composition within atherosclerotic plaque tissue was different from the chain composition in the media. In addition, obvious differences in laminin chain composition could be observed in areas of the media, which were or were not associated with plaque tissue. Our major findings demonstrate that laminin gamma3 was exclusively present in media associated with plaque tissue. Laminin alpha2 was also enriched in these medial areas. Plaque tissue was predominantly enriched in laminin alpha5 chains. This general distribution applied to lesions both with and without a fibrous cap-like structure. The differential distribution of laminin chains were partially accompanied by changes in the presence of the integrin alpha subunits 7 and V.
The distribution of laminin chains in human atherosclerotic arteries, with different size and morphology, grossly resembled their distribution in mouse arteries. Histol Histopathol 26, 711-724 (2011)
Key words: Laminin, Atherosclerosis, Smooth muscle cell
DOI: 10.14670/HH-26.711