Olive oil addition to the high-fat diet reduces methylglyoxal (MG-H1) levels increased in hypercholesterolemic rabbits

Methylglyoxal (MG) is a highly reactive compound derived from sugar metabolism, precursor of cytotoxic products named Advanced Glycation End products (AGEs). Increased MG levels and MG-related AGEs have been long associated with diabetes and its complications. The association between MG and hypercholesterolemia -induced by high-fat diets- has not been studied previously, neither the effect of olive oil addition to this diets. OBJECTIVE: To analyze the variations of MG and cholesterol levels under the effect of high-fat and olive oil-enriched diets. METHODS: Sixteen healthy male adult (New Zealand White, 6 months old) rabbits were fed with commercial pellets (control, four rabbits), or with 14% of bovine grease added to the pellets (high-fat diet, twelve rabbits). After six months, bovine grease was reduced to 7% (half fat diet, eight rabbits). Then, 7% of olive oil was added to the pellets (protective diet, four rabbits). Glycaemia, cholesterolemia, HDL-cholesterolemia, triglyceridemia, fructosamine and MG-H1 levels were assessed in all experimental conditions (n = 4). RESULTS: The high-fat diet promoted a hypercholesterolemia associated with increased MG-H1 levels (p > 0.05) in nondiabetic and non-obese rabbits. Replacement of the high-fat diet with olive oil decreased significantly the cholesterolemia and MG-H1 levels (p > 0.05). CONCLUSIONS:Our data indicates that the replacement of a high-fat diet with olive oil can recover normal blood cholesterol values and can decrease MG-H1 levels.