-The Duchenne muscular systrophy (DMD) is a muscular dystrophy with cognitive impairment present in 20-30% of the cases. In the present study, in order to study the relationship between the α-dystroglycan (α-DG) immunostaining in skeletal muscle and cognitive performance in DMD patients, 19 were assessed. Twelve patients performed the intelligence quotient (IQ) below the average. Among the 19 patients, two were assessed by the Stanford-Binet test and 17 by Wechsler Intelligence Scale for Children-III (WISC-III). Nine patients performed a verbal IQ below the average, only three patients performed an average verbal IQ. The muscle biopsies immunostained with antibodies to α-DG showed that 17 patients presented a low expression, below 25% of the total fibers. Two patients presented α-DG immunostaining above 40% and an IQ within the average. No significant statistical relationship was demonstrated among total IQ, verbal IQ and execution IQ and α-DG immunostaining at these patients muscle samples.KEY WORDS: Duchenne muscular dystrophy, α-dystroglycan, cognitive impairment, dystrophin.
Distrofia muscular de Duchenne: imunoexpressão da α-distroglicana em musculatura esqueléti-ca e performance cognitivaRESUMO -A distrofia muscular de Duchenne (DMD) é uma distrofia muscular com comprometimento cognitivo presente em 20-30% dos casos. No presente estudo, com a finalidade de estudar a relação entre a imunoexpressão da α-distroglicana (α-DG) em musculatura esquelética e a performance cognitiva em pacientes com DMD, foram avaliadas 19 crianças. Doze pacientes apresentaram o quociente de inteligência (QI) abaixo da média. Entre os 19 pacientes, dois foram avaliados pelo teste de Stanford-Binet e 17 pelo Wechsler Intelligence Scale para crianças-III (WISC-III). Nove apresentaram QI verbal abaixo da média, e apenas três QI verbal na média. As biopsias musculares com os anticorpos para α-DG mostraram que 17 pacientes apresentaram baixa expressão, abaixo de 25% do total de fibras. Dois pacientes apresentaram a imunoexpressão da α-DG acima de 40% e QI dentro da média. Não foi demonstrada relação estatisticamente significante entre o QI total, QI verbal e QI de execução e a imunoexpressão da α-DG . PALAVRAS-CHAVE: distrofia muscular de Duchenne, α-distroglicana, déficit cognitivo, distrofina.The Duchenne muscular dystrophy (DMD) is defined as an X linked recessive disorder, and the main features being progressive muscular weakness related to dystrophin protein deficiency in the skeletal muscle 1 . There is a wide range of symptoms in DMD, which delay diagnosis, because the initial observations are non-specific and the age when boys present the first symptoms is variable 2 . In the majority of boys, the common symptoms begin, before four years old, and are commonly characterized by abnormal gait, walking with difficulty and frequent fall overs. Other symptoms include delays in motor milestones and awkward gait 1 . The DMD is characterized by the absence of dystrophin the skeletal muscle 3 . The dystrophin is a protein that is...