Bariatric surgery induces morphological changes in the extensor digitorum longus muscle in the offspring of obese rats.

INTRODUCTION: The effects of the maternal nutritional environment on the growth and metabolism of the offspring, and its impacts on health in adult life are defined as metabolic programming. Thus, the objective of this study was to evaluate the effects of Roux-en-Y gastric bypass (RYGB) on the morphology of muscle fiber and neuromuscular junction (NMJ) of the offspring of rats submitted to RYGB. METHODS: Three-week-old Wistar rats were separated into two groups: 1) CAF SHAM which received a cafeteria diet and was submitted to a sham operation and 2) CAF RYGB, which received a cafeteria diet and was submitted to RYGB. The first generation (F1) offspring (male) was named according to the treatment of mothers as CAF SHAM-F1 and CAF RYGB-F1 and received a standard diet after weaning. At 17 weeks, the animals were euthanized, and the extensor digitorum longus muscle (EDL) was collected and processed in light microscopy and transmission electron microscopy for morphological and morphometric analysis. RESULTS: The CAF RYGB-F1 group showed a reduction in the weight of the EDL muscle and also a reduction in the area of type I, IIa and IIb fibers and a nucleus/fiber ratio. This same group also showed an increase in the capillary density and myofibrillar disorganization and in the Z-line, as well as a reduction in the area of the NMJs. CONCLUSION: The RYGB surgery in mothers produced morphological changes in the skeletal striated muscles of the offspring.

An evaluation of an animal model of cerebral palsy: the effects on the morphology of the extensor digitorum longus muscle / Evaluación de un modelo animal de parálisis cerebral: los efectos sobre la morfología del músculo extensor largo de los dedos

Cerebral Palsy (CP) refers to chronic childhood encephalopathy. The objective of this study was to verify effects of CP model that combines prenatal exposure to LPS, perinatal anoxia and sensorimotor restriction on EDL muscle. Male Wistar rat pups were separated: a) Control - pups of mothers injected with saline during pregnancy and b) Cerebral Palsy - pups of mothers injected with LPS during pregnancy, and submitted to perinatal anoxia and sensorimotor restriction. The CP group presented hypertrophy in the type IIB fibers and increase of nuclei/fiber and capillary/fiber ratios. The intrafusal fibers of CP group presented 26 % atrophy in the crosssectional area and intramuscular collagen volume increase 34 %. CP group showed myofibrillar disruption and Z-line disorganization and the NMJs presented increases of 22 % in area.This animal model of CP produces motor deficits and macro and microscopic alterations and in the ultrastructure of the EDL muscle.

La parálisis cerebral (PC) se refiere a la encefalopatía crónica infantil. El objetivo de este estudio fue verificar los efectos del modelo PC que combina la exposición prenatal a LPS, la anoxia perinatal y la restricción sensitivo-motora en el músculo extensor largo de los dedos (MELD). Se separaron las crías de ratas Wistar machos: a) Control: crías de madres inyectadas con solución salina durante la preñez y b) Parálisis cerebral: crías de madres inyectadas con LPS durante la preñez y sometidas a anoxia perinatal y restricción sensitivo-motora. El grupo PC presentó hipertrofia en las fibras tipo IIB y aumento de la relación núcleo / fibra y capilar / fibra. Las fibras intrafusales del grupo PC presentaron un 26 % de atrofia en el área de la sección transversal y el volumen de colágeno intramuscular aumentó un 34 %. El grupo PC mostró disrupción miofibrilar y desorganización de la línea Z y los NMJ presentaron aumentos de 22 % en el área. Este modelo animal de PC produce déficit motores y alteraciones macro y microscópicas y cambios en la ultraestructura del MELD.