Accelerated evolution of brain atrophy and "black holes" in MS patients with APOE-epsilon 4.
ABSTRACT Apolipoprotein E (APOE)-epsilon4 has been associated with an unfavorable course of multiple sclerosis (MS). The mechanisms responsible for this are unclear, although cross-sectional MRI demonstrated a higher extent of "black holes" (BHs) in such patients. Here, we have studied the impact of the APOE genotype on both the longitudinal evolution of focal (BH ratio) and global (brain volume change [BVC]) brain tissue damage. Ninety-nine MS patients underwent ApoE genotyping, clinical examination, and magnetic resonance imaging at baseline and after 2.7 +/- 1.1 years to assess lesion load (LL) and BVC. In APOE-epsilon4 patients, the annual reduction in brain volume was fivefold higher (-0.65 +/- 0.61%) than in those without APOE-epsilon4 (-0.13 +/- 0.36%; p = 0.0001). At baseline, T(2) LL and T(1) LL were non-significantly higher in epsilon4 carriers, despite a shorter disease duration and absence of significant clinical differences. During follow-up, T(1) LL increased from 1.2 +/- 2.3 ccm to 1.7 +/- 2.7 ccm in the epsilon4 group, although T(2) LL did not change, leading to a significantly higher increase in the BH ratio [(T(1) LL/T(2) LL) x 100] from 5.5 to 12.4% (p = 0.005). BH ratio remained almost constant in non-epsilon4 patients (5.0 vs 5.7%). Accelerated brain tissue loss and a higher proportion of lesions evolving into BH therefore provide magnetic resonance imaging evidence for more pronounced tissue destruction in MS patients with APOE-epsilon4.
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ABSTRACT: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder of the central nervous system. Evidences linking apolipoprotein E (APOE) to myelin repair, neuronal plasticity, and cerebral inflammatory processes suggest that it may be relevant in MS. The main goal of this study was to determine whether the APOE genotypes and alleles are associated with MS patients. In total, 147 MS cases and 168 control subjects from Iranian population were genotyped for APOE gene using PCR-RFLP method. The frequency of APOE-ε2ε3 genotype was significantly higher in controls than cases (14.3% vs. 6.1%, P=0.009, OR=0.39) whereas APOE-ε3ε4 genotype frequency was significantly higher in cases compared with controls (8.2% vs. 3.6%, P=0.03, OR=2.4). APOE-ε2 allele frequency in cases was significantly lower than that of controls (4.4% vs. 8.0%, P=0.03, OR=0.52). Also male controls were significantly more likely to have APOE-ε2 allele (7.8% vs. 1%, P=0.01, OR=0.11). APOE-ε4 allele frequency in cases was significantly higher than control group (4.8% versus 2.1%, P=0.03, OR=2.35). It seems that individuals carrying APOE-ε4 allele and/or APOE-ε3ε4 genotype develop MS two times more than non-carriers. Also APOE-ε2ε3 genotype or APOE-ε2 allele may have a protective role against MS development in Iranian population. Further investigation would be warranted to understand the role of APOE alleles and genotypes and risk of MS.Journal of the neurological sciences 06/2012; 320(1-2):22-5. · 2.32 Impact Factor
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ABSTRACT: The goal of this work was to assess brain structural and metabolic abnormalities of subjects with SPG11 and their relevance to clinical disability by using quantitative magnetic resonance (MR) metrics. Autosomal recessive hereditary spastic paraplegia (AR-HSP) with thin corpus callosum and cognitive decline is a complex neurological disorder caused by mutations in the SPG11 gene in most cases. Little is known about the process leading to corticospinal and white matter degeneration. We performed conventional MRI/MR spectroscopic imaging ((1)H-MRSI) examinations in 10 HSP patients carrying an SPG11 mutation and in 10 demographically matched healthy controls (HC). We measured in each subject cerebral white matter hyperintensities (WMHs), normalized global and cortical brain volumes, and (1)H-MRSI-derived central brain levels of N-acetylaspartate (NAA) and choline (Cho) normalized to creatine (Cr). Clinical disability was assessed according to patients' autonomy in walking. Conventional MRI showed WMHs in all patients. Global brain volumes were lower in patients than in HC (p < 0.001). Decreased values were diffusely found also in cortical regions (p < 0.01). On (1)H-MRSI, NAA/Cr values were lower in SPG11 patients than in HC (p = 0.002). Cho/Cr values did not differ between patients and HC. Cerebral volume decreases and NAA/Cr in the corona radiata correlated closely with increasing disability scores (p < 0.05). Quantitative MR measures propose that widespread structural and metabolic brain damage occur in SPG11 patients. The correlation of these MR metrics with measures of patients' disease severity suggests that they might represent adequate surrogate markers of disease outcome.Journal of Neurology 05/2011; 258(12):2240-7. · 3.58 Impact Factor
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ABSTRACT: Evidence linking the ε4 allele of APOE to more severe brain MRI abnormalities in multiple sclerosis (MS) has been conflicting and limited to studies of lesion load and whole brain atrophy. The purpose of the present study was to determine whether the ε4 allele of APOE is associated with more extensive brain pathology in MS using structural and diffusion tensor MRI. Using a case-control design, 43 MS patients with the ε4 allele and 47 ε4 negative MS patients underwent structural and diffusion tensor imaging (DTI) at 3T. Hypo- and hyperintense lesion volumes, whole brain and medial temporal volumes, and DTI parameters (fractional anisotropy (FA) and mean diffusivity (MD)) in normal-appearing brain tissue and lesions were compared between the groups. ε4+ and ε4- MS patients were well-matched on demographic characteristics, disease variables, and proportions receiving disease-modifying therapy. ε4+ and ε4- patients did not differ on any MRI or DTI measure. This study refutes a role for the ε4 allele in MRI abnormalities in MS, particularly those linking ε4 to greater T1 hypointense lesion volume and brain atrophy. Previous work on this putative gene-MRI relationship is extended by comparing DTI measures within lesions and normal-appearing brain tissue. A lack of differences in medial temporal regions, areas that have been linked to ε4-associated changes in health and disease, further supports the conclusion that that ε4 is not associated with more subtle MRI markers of brain pathology in MS.NeuroImage 06/2011; 58(3):724-31. · 6.25 Impact Factor