Metals and electrolytes in sclerotic hippocampi in patients with drug-resistant mesial temporal lobe epilepsy

Abstract

An altered metal and electrolyte profile has been implicated in the pathologic mechanisms of chronic epilepsy; however, no study has comprehensively measured hippocampal concentrations of these elements in patients with mesial temporal lobe epilepsy and hippocampal sclerosis (mTLE-HS). We therefore analyzed hippocampi of 24 patients with drug-resistant mTLE-HS (mean age 35.69.4years) who underwent anterior temporal lobe resection and amygdalohippocampectomy and 17 hippocampi obtained by autopsy from 13 controls (mean age 40.5 +/- 12.9years), using inductively coupled plasma optical emission spectrometry (ICP-OES). Epileptic hippocampi showed significantly lower concentrations (g/g of tissue) of copper (HS: 2.34 +/- 0.12; control {[}C]: 3.57 +/- 0.33; p<0.001), manganese (HS: 0.205 +/- 0.030; C: 0.409 +/- 0.064; p=0.004), and potassium (HS: 2,001 +/- 59; C: 2,322 +/- 61; p<0.001), and increased sodium levels (HS: 1,131 +/- 22; C: 1,040 +/- 25; p=0.010). Zinc, iron, calcium, and magnesium levels did not differ in HS and controls. In summary, copper and manganese levels are deficient, whereas iron level is unchanged in hippocampi from patients with mTLE-HS. Our results provide a basis for understanding the potential involvement of different metals and electrolytes in the pathology of HS. A PowerPoint slide summarizing this article is available for download in the Supporting Information section .