Morphological changes of extensor digitorum longus muscle in the offspring of obese rats

Objective: To evaluate the morphology and morphometry of muscle fibers and neuromuscular junctions (NMJs) of the extensor digitorum longus muscle (EDL) in the offspring of obese ratsinduced by a cafeteria diet. Methods: Three-week-old female Wistar rats were randomly divided into two groups: a control (CTL) group that received a standard diet and an obese (OB) group that received a cafeteria diet. The animals were mated at 23 weeks of age. After birth, only males were used for the experiment. The offspring of the first generation (F1) were designated CTL-F1 and OB-F1 according to the treatment of the mothers and received the standard diet. The animals were euthanized at 17 weeks of age and the EDL muscle was collected and routinely processed for morphological and morphometric analysis by light microscopy and transmission electron microscopy. Results: The body weight, retroperitoneal and periepididymal fat weight and capillary/fiber ratio were higher in the OB-F1 group compared to CTL-F1. However, a reduction in the number of nuclei, connective tissue, ultrastructural parameters, and NMJ area and largest diameter o was observed in the OB-F1 group. Conclusion: Feeding mothers an obesogenic diet throughout life induces morphological and morphometric changes in the skeletal muscle fibers and NMJs of their offspring in later life.