Rhamnan sulfate reduces atherosclerotic plaque formation and vascular inflammation.

OBJECTIVE: While lipid-lowering drugs have become a mainstay of clinical therapy these treatments only slow the progression of the disease and can have side effects. Thus, new treatment options are needed to supplement the effects of lipid lowering therapy for treating atherosclerosis. We examined the use of an inexpensive and widely available marine polysaccharide rhamnan sulfate as an oral therapeutic for limiting vascular inflammation and atherosclerosis. METHODS AND RESULTS: We found rhamnan sulfate enhanced the barrier function of endothelial cells, preventing the deposition of LDL and maintaining barrier function even in the presence of glycocalyx-degrading enzymes. Rhamnan sulfate was also found to bind directly to FGF-2, PDGF-BB and NF-κB subunits with high affinity. In addition, rhamnan sulfate was a potent inhibitor of NF-κB pathway activation in endothelial cells by TNF-α. We treated ApoE-/- mice with a high fat diet for 4 weeks and then an addition 9 weeks of high fat diet with or without rhamnan sulfate. Rhamnan sulfate reduced vascular inflammation and atherosclerosis in both sexes of ApoE-/- mice but had a stronger therapeutic effect in female mice. Oral consumption of rhamnan sulfate induced a significant decrease in cholesterol plasma levels in female mice but not in male mice. In addition, there was a marked reduction in inflammation for female mice in the liver and aortic root in comparison to male mice. CONCLUSIONS: Rhamnan sulfate has beneficial effects in reducing inflammation, binding growth factors and NF-κB, enhancing endothelial barrier function and reducing atherosclerotic plaque formation in ApoE-/- mice.

Intensive treatment with atorvastatin reduces inflammation in mononuclear cells and human atherosclerotic lesions in one month.

BACKGROUND AND PURPOSE: To investigate the effect of short-term high-dose atorvastatin on blood and plaque inflammation in patients with carotid stenosis. METHODS: Twenty patients undergoing carotid endarterectomy without previous statin treatment were randomized to receive either atorvastatin 80 mg/d (n=11) or no statins (n=9) for 1 month. We studied inflammatory mediators in plasma (enzyme-linked immunosorbent assay), peripheral blood mononuclear cells (PBMCs; quantitative RT-PCR and EMSA) and plaques (immunohistochemistry and Southwestern histochemistry). RESULTS: Atorvastatin significantly decreased total and low-density lipoprotein cholesterol and prostaglandin E2 plasma levels. PBMCs from treated patients showed impaired NF-kappaB activation and MCP-1 and COX-2 mRNA expression. Carotid atherosclerotic plaques demonstrated a significant reduction in macrophage infiltration, activated NF-kappaB, and COX-2 and MCP-1 expression. CONCLUSIONS: Intensive treatment with atorvastatin decreases inflammatory activity of PBMCs and carotid atherosclerotic plaques in 1 month. These data strongly suggest that the antiinflammatory effect of high doses of statins in humans can be seen very early.