title: Use of combined chemotherapy with etoposide and methotrexate, both associated to lipid nanoemulsions for atherosclerosis treatment in cholesterol-fed rabbits.
abstract: OBJECTIVE
  Treatment of atherosclerotic rabbits with intravenous methotrexate or etoposide carried in lipid nanoemulsions (LDE) markedly reduced the lesions in the aorta. Here, the combined treatment with LDE-methotrexate and LDE-etoposide was investigated aiming to increase the anti-atherosclerosis effect.
  
  
  METHODS
  Thirty-six male rabbits received a diet with 1 % cholesterol for 2 months. After the first month, the animals received 4 weekly intravenous injections of LDE-methotrexate (4 mg/kg dose), LDE-etoposide (6 mg/kg), or a combination of those two drugs, while the control animals were injected with LDE (n = 9 for each group).
  
  
  RESULTS
  LDE-methotrexate+LDE-etoposide reduced aortic lesion areas by 95 % compared with controls and the intima-media ratio was reduced five-fold, whereas LDE-methotrexate reduced the lesions by 81 % and LDE-etoposide by 83 %. Compared to controls, the positive area of macrophages and MMP-9 in the arterial intima was significantly reduced in all treated groups (p < 0.001), but the MMP9 reduction was greater with the combined chemotherapy than the reduction achieved by the isolated treatments. Presence of CD3 positive cells was equal in controls and LDE-methotrexate+LDE-etoposide treated animals. However, FOXP3 positive T lymphocytes in the intima were increased in the LDE-methotrexate+LDE-etoposide rabbits. Weight, food intake evolution and the hematologic parameters suggested that the treatment had very low toxicity.
  
  
  CONCLUSIONS
  Compared to the single treatments with LDE-methotrexate and LDE-etoposide, the combined treatment was more effective in reducing the atherosclerotic lesions. Because the toxicity of the novel drug-target combined scheme was low, those results favor the possibility of future clinical studies in patients with cardiovascular disease.
authors: Lipid Metabolism Laboratory, Heart Institute (INCOR) and the Medical School Hospital, São Paulo, Av. Dr. Eneas C. Aguiar 44, 1 subsolo, São Paulo, SP, CEP 0543000, Brazil.
authors: Antonio C A
authors: AC
authors: Leite
authors: Tatiana V
authors: TV
authors: Solano
authors: Elaine R
authors: ER
authors: Tavares
authors: Raul C
authors: RC
authors: Maranhão
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000473:pathology; D050197:Atherosclerosis / Q000188:drug therapy* / Q000473:pathology; D004359:Drug Therapy, Combination; D004655:Emulsions; D005047:Etoposide / Q000008:administration & dosage* / Q000627:therapeutic use; D008055:Lipids / Q000008:administration & dosage* / Q000737:chemistry; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage* / Q000627:therapeutic use; D049329:Nanostructures / Q000008:administration & dosage* / Q000737:chemistry; D011817:Rabbits
chemical_list: D004655:Emulsions; D008055:Lipids; D005047:Etoposide; D008727:Methotrexate