Chemokine RANTES is upregulated in monocytes from patients with hyperhomocysteinemia.

Aim: To investigate the changes in plasma level of the chemokine RANTES (regulated upon activation, normal T cells expressed and secreted) and the responsiveness of lipopolysaccharide (LPS)-induced RANTES secretion from monocytes in patients with hyperhomocysteinemia (HHcy).

Methods: The plasma levels of homocysteine (Hcy), folate, and RANTES were measured in 38 control patients with normal Hcy levels and 40 patients with HHcy and the mRNA synthesis of RANTES in isolated human monocytes was determined by RNase protection assays.

Results: The plasma level of RANTES was elevated in HHcy patients compared with controls (median 5.

Signal pathways underlying homocysteine-induced production of MCP-1 and IL-8 in cultured human whole blood.

Aim: To elucidate the mechanisms underlying homocysteine (Hcy)-induced chemokine production.

Methods: Human whole blood was pretreated with inhibitors of calmodulin (CaM), protein kinase C (PKC), protein tyrosine kinase (PTK), mitogen-activated protein kinase (MAPK), and NF-kappaB and activators of PPARgamma for 60 min followed by incubation with Hcy 100 micromol/L for 32 h. The levels of mitogen chemokine protein (MCP)-1 and interleukin-8 (IL-8) were determined by enzyme-linked immunosorbant assay (ELISA).

Homocysteine induces production of monocyte chemoattractant protein-1 and interleukin-8 in cultured human whole blood.

Aim: To investigate whether increased plasma L-homocysteine (Hcy) level could promote monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) in cultured whole blood.

Methods: Human whole blood or different type of peripheral blood cells from health volunteers were incubated with Hcy and/or the inhibitors. MCP-1 and IL-8 level were measured by ELISA assay.