APBB2 genetic polymorphisms are associated with severe cognitive impairment in centenarians
EXPERIMENTAL GERONTOLOGY
Authors: Golanska, Ewa; Sieruta, Monika; Gresner, Sylwia M.; Pfeffer, Anna; Chodakowska-Zebrowska, Malgorzata; Sobow, Tomasz M.; Klich, Izabela; Mossakowska, Malgorzata; Szybinska, Aleksandra; Barcikowska, Maria; Liberski, Pawel P.
Abstract
APBB2 gene encodes for beta-amyloid precursor protein-binding family B member 2, (APBB2, FE65-like, FE65L1), an adaptor protein binding to the cytoplasmatic domain of beta-amyloid precursor protein (beta APP). Over-expression of APBB2 promotes formation of beta-amyloid (A beta), the main constituent of senile plaques. Polymorphisms within APBB2 gene have been proposed as candidate risk factors for Alzheimer's disease. However, their association with longevity has never been investigated. Here we present the first attempt to analyze APBB2 polymorphisms in centenarians. We used a PCR-RFLP method to analyze two intronic nucleotide substitutions: hCV1558625 (rs17443013) and rs13133980. We found no differences in genotype or allele distribution between centenarians and young controls. After stratification of centenarians upon their cognitive performance, the APBB2 rs13133980 G allele was over-represented in centenarians with severe cognitive impairment compared to individuals without this disability. Also the hCV1558625-rs13133980 AG haplotype increased relative risk for severe cognitive impairment in centenarians. Our results support the concept of APBB2 polymorphism association with cognitive performance in the oldest age. (C) 2013 Elsevier Inc. All rights reserved.
Repeated Traumatic Brain Injury Affects Composite Cognitive Function in Piglets
JOURNAL OF NEUROTRAUMA
Authors: Friess, Stuart H.; Ichord, Rebecca N.; Ralston, Jill; Ryall, Karen; Helfaer, Mark A.; Smith, Colin; Margulies, Susan S.
Abstract
Cumulative effects of repetitive mild head injury in the pediatric population are unknown. We have developed a cognitive composite dysfunction score that correlates white matter injury severity in neonatal piglets with neurobehavioral assessments of executive function, memory, learning, and problem solving. Anesthetized 3- to 5-day-old piglets were subjected to single (n=7), double one day apart (n=7), and double one week apart (n=7) moderate (190 rad/s) rapid non-impact axial rotations of the head and compared to instrumented shams (n=7). Animals experiencing two head rotations one day apart had a significantly higher mortality rate (43%) compared to the other groups and had higher failures rates in visual-based problem solving compared to instrumented shams. White matter injury, assessed by beta-APP staining, was significantly higher in the double one week apart group compared to that with single injury and sham. Worsening performance on cognitive composite score correlated well with increasing severity of white matter axonal injury. In our immature large animal model of TBI, two head rotations produced poorer outcome as assessed by neuropathology and neurobehavioral functional outcomes compared to that with single rotations. More importantly, we have observed an increase in injury severity and mortality when the head rotations occur 24 h apart compared to 7 days apart. These observations have important clinical translation to infants subjected to repeated inflicted head trauma.