Morphofunctional characteristics of skeletal muscle in rats with cerebral palsy

Abstract

Summary Knowledge of skeletal muscle adaptations is important to understand the functional deficits in cerebral palsy (CP). This study aimed to investigate the morphofunctional characteristics of skeletal muscle in a CP animal model. Initially, pregnant Wistar rats were injected intraperitoneally with saline or lipopolysaccharide over the last five days of pregnancy. The control group (n = 8) consisted of male pups born to females injected with saline. The CP group (n = 8) consisted of male pups born to females injected with lipopolysaccharide, which were submitted to perinatal anoxia [day of birth, postnatal day 0 (P0)] and sensorimotor restriction (P1‐P30). The open‐field test was undertaken on P29 and P45. On P48, the animals were weighed, and the plantaris muscle was collected and its weight and length were measured. Transverse sections were stained with haematoxylin‐eosin, NADH‐TR, Masson's trichrome and non‐specific esterase reaction for analysis. and transmission electron microscopy was performed. In the CP group, reductions were observed in mobility time, number of crossings and rearing frequency, body weight, muscle weight and length, and nucleus‐to‐fibre and capillary‐to‐fibre ratios. There was a statistically significant increase in the percentage area of the muscle section occupied by collagen; reduction in the area and increase in the number of type I muscle fibres; increase in myofibrillar disorganization and Z‐line disorganization and dissolution; and reduction in the area and largest and smallest diameters of neuromuscular junctions. Thus this animal model of CP produced morphofunctional alterations in skeletal muscle, that were associated with evidence of motor deficits as demonstrated by the open‐field test.

Neonatal kaempferol exposure attenuates gait and strength deficits and prevents altered muscle phenotype in a rat model of cerebral palsy

“…Concurring with our results, Buratti et al (2019) observed that rats subjected to a CP model showed reduced body weight, muscle weight and length and a reduction in the area and increase in the number of type I muscle fibres in the plantaris muscle (Buratti et al, 2019). Studies using the same CP model have found reduced muscle mass in the soleus and tibialis anterior muscle (Marques et al, 2014; Stigger et al, 2011).…”

Maternal exposure to glyphosate‐based herbicide promotes changes in the muscle structure of C57BL/6 mice offspring

“…For morphometric analysis, the area and major and minor diameters of 80 NMJs per animal were determined on microscopic images (×20 objective) by a statistician as also performed in other studies (Buratti et al, 2019; Covatti et al, 2018; Estrada‐Bonilla et al, 2020; Jeronimo et al, 2018; Kuhn et al, 2021).…”

Early neurodevelopmental reflex impairments in a rodent model of cerebral palsy

“…Thus, the period without cast restriction is vital for them to find the nest in order to be nourished and a rapid compensatory sensory maturation of other sensory modalities can occur in order to supply the delay in locomotor development caused by hindlimbs restriction (Smirnov & Sitnikova, 2019). In this sense, most literature using sensorimotor restriction as one component of CP modeling shows decreased body weight in the offspring (Buratti et al, 2019;Delcour, Massicotte, et al, 2018;Lacerda et al, 2017Lacerda et al, , 2019Marcuzzo et al, 2008Marcuzzo et al, , 2010Marques et al, 2014;Sanches et al, 2021;Strata et al, 2004), confirming a recent report pointing to nutritional deficits in CP patients (da Silva et al, 2022). In conclusion, we show that neurodevelopmental milestones are altered in a rodent model of CP based on brain damage and sensorimotor deprivation reinforcing its validity in the study of CP outcomes.…”