Effect of citric acid and maltol on the accumulation of aluminum in rat brain and bone.

Deposition of aluminum in the body is responsible for the development of dialysis-related diseases in patients with renal dysfunction and may play a role in the development of certain neurodegenerative disorders. Although citric acid is known to be a strong enhancer of gastrointestinal absorption of aluminum, its effect on aluminum distribution and accumulation is not yet clear. Maltol has been shown to increase the neurotoxicity of aluminum, but little is known about its effect on aluminum deposition in the body. To elucidate the role of citric acid and maltol in aluminum accumulation and toxicity, rats were loaded intraperitoneally during a 7-day period with different amounts of aluminum chloride in absence or presence of citric acid or maltol before analysis of aluminum in serum, brain, bone, and urine. Coadministration of citric acid led to relatively reduced serum levels, as compared with aluminum and aluminum-maltol treatment. This is explained by both tissue elimination and enhanced renal elimination. Only at the highest aluminum dose (8 mg/kg body weight) was an enhancing effect of citric acid on accumulation of aluminum in brain observed; no effect on bone aluminum was seen. Furthermore, it was seen that citric acid alters the distribution pattern of aluminum. This may be explained by the postulation of a characteristic aluminum citrate species in serum. Administration of citric acid may increase this aluminum fraction in serum, thereby inducing an alteration of the distribution pattern. Maltol was shown to be a strong enhancer of aluminum accumulation in serum, brain, and bone. The rise of aluminum in these target tissues was dose dependent.(ABSTRACT TRUNCATED AT 250 WORDS)