Describing nutrition in spinal muscular atrophy: A systematic review.

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease of variable severity. Progressive muscle wasting and impairment in functional ability in SMA have a profound influence on nutritional outcomes. This systematic review summarises the existing evidence on nutrition in SMA. The search strategy was conducted across five databases in August 2014, and updated in March 2016, using key terms relating to growth, nutrition requirements, dietary intake and nutrition management. Studies were selected for inclusion using a two pass method, and data systematically extracted using standardised forms. Thirty-nine studies met eligibility criteria. Body composition is abnormal in patients with SMA, and feeding and swallowing issues are prevalent among sufferers of SMA types I and II. Nutritional management practices vary internationally. There is a paucity of literature regarding nutrition requirements in SMA, although it appears that energy expenditure may be reduced. Children with SMA require individualised nutritional management in order to address their growth and nutrition requirements. There is an urgent need for larger, coordinated, prospective intervention studies of nutrition in SMA.

Effect of diet on the survival and phenotype of a mouse model for spinal muscular atrophy.

Proximal spinal muscular atrophy (SMA) is a leading genetic cause of infant death. Patients with SMA lose alpha-motor neurons in the ventral horn of the spinal cord which leads to skeletal muscle weakness and atrophy. SMA is the result of reduction in Survival Motor Neuron (SMN) expression. Transgenic mouse models of SMA have been generated and are extremely useful in understanding the mechanisms of motor neuron degeneration in SMA and in developing new therapeutic candidates for SMA patients. Several research groups have reported varying average lifespans of SMNDelta7 SMA mice (SMN2(+/+);SMNDelta7(+/+);mSmn(-/-)), the most commonly used mouse model for preclinical therapeutic candidate testing. One environmental factor that varied between research groups was maternal diet. In this study, we compared the effects of two different commercially available rodent chows (PicoLab20 Mouse diet and Harlan-Teklad 22/5 diet) on the survival and motor phenotype of the SMNDelta7 mouse model of SMA. Specifically, the PicoLab20 diet significantly extends the average lifespan of the SMNDelta7 SMA mice by approximately 25% and improved the motor phenotype as compared to the Harlan diet. These findings indicate that maternal diet alone can have considerable impact on the SMA phenotype.