title: Protein Malnutrition Pre- and Postnatal and Nutritional Rehabilitation Modulates the Morphology of Muscle Fibers in Wistar Rats.
abstract: This study investigated the effects of pre- and postnatal conditions of protein deficiency followed to nutritional rehabilitation in the morphology of skeletal muscle. Twelve Wistar male rats were distributed in two groups: nourished (N), with normal protein diet and undernourished (U), with low protein diet. The respective diet was maintained until animals completed 21 days of life. After that, part of group U (n = 4) received normal protein diet, forming a third group, renourished group (R). Forty-two-day-old animals were euthanized and we performed histopathological and morphometric analysis of the soleus muscle. Analysis stained in hematoxylin and eosin (H&E) of the group N revealed polygonal and equidistant muscle fibers, with normal distribution in muscle fascicles. However, D group had rounded and disorganized fibers with different distances between them in muscle fascicles. R group presented muscle fibers with several formats, polygonal and rounded, and some muscle fascicles starting the reorganization process. In N group, analysis of the connective tissue showed predominance of type I collagen and a lower amount collagen type III, both well organized. Whereas U group had a predominance of disorganized type III collagen, in R group, there was return of type I collagen, but partially organized. Muscle fiber area of U (163.18 ± 52.55 μm2) and R (381.79 ± 26.62 μm2) groups was smaller than N (1229.2 μm2± 61.12 μm2). Muscle fibers density of groups U (3369 ± 1226 fibers/mm2) and R (1979 ± 28 fibers/mm2) was larger than N (830 ± 113 fibers/mm2). The nutritional rehabilitation in the present study showed an attempt of reorganization of the muscle tissue.
authors: a Department of Biosciences , Federal University of São Paulo , SP , Brazil.
authors: Thays de Souza
authors: TS
authors: Lopes
authors: a Department of Biosciences , Federal University of São Paulo , SP , Brazil.
authors: Hananiah Tardivo
authors: HT
authors: Quintana
authors: a Department of Biosciences , Federal University of São Paulo , SP , Brazil.
authors: Jeferson André
authors: JA
authors: Bortolin
authors: b Institute of Biological Sciences , University of São Paulo , SP , Brazil.
authors: Paulo Henrique
authors: PH
authors: Matos Alves
authors: b Institute of Biological Sciences , University of São Paulo , SP , Brazil.
authors: Regina de Souza
authors: RS
authors: Bolina Matos
authors: b Institute of Biological Sciences , University of São Paulo , SP , Brazil.
authors: Edson Aparecido
authors: EA
authors: Liberti
authors: a Department of Biosciences , Federal University of São Paulo , SP , Brazil.
authors: Flavia de
authors: F
authors: Oliveira
mesh_terms: D000818:Animals; D018753:Diet, Protein-Restricted / Q000009:adverse effects*; D004044:Dietary Proteins / Q000008:administration & dosage*; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000378:metabolism / Q000473:pathology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology*; D011502:Protein-Energy Malnutrition / Q000178:diet therapy / Q000378:metabolism / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004044:Dietary Proteins
keywords: connective tissue; dietary proteins; metabolism; morphology; skeletal muscle; undernutrition