Comparative study of calcium and calcium-related enzymes with differentiation markers in different ages and muscle types in mdx mice
Rhayanna B. Gaglianone1,2, Flavia Fonseca Bloise3, Tania Maria Ortiga-Carvalho3, Thereza Quirico-Santos2, Manoel Luis Costa1 and Claudia Mermelstein1
1Biomedical Sciences Institute, Federal University of Rio de Janeiro, 2Biology Institute, Fluminense Federal University, Niterói and 3Carlos Chagas Filho Biophysical Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
Offprint requests to: Claudia Mermelstein, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. e-mail: mermelstein@ufrj.br or mermelstein@histo.ufrj.br
Summary. Sarcolemma instability and increased calcium influx in muscle fibers are characteristics of the Duchenne muscular dystrophy. Excessive calcium activates calcium-dependent enzymes, such as calpains (CAPN) and matrix metalloproteases (MMP). Here, we analyzed calcium deposits, the activity of CAPN and MMP and the expression of Myh, SERCA and myogenic regulatory factors in different skeletal muscles during myonecrosis (4-weeks) and regeneration (12-weeks) phases of the mdx muscular pathology. Alizarin red staining was used to assess calcium deposits, casein and gelatin zymography were performed to evaluate CAPN and MMP activity, and qPCR was used to evaluate the expression of Myh, Capn, Atp2a1 and Atp2a2, Myod1 and Myog. We observed the following characteristics in mdx muscles: (i) calcium deposits almost exclusively in mdx muscles, (ii) lower CAPN1 activity in mdx muscles, (iii) higher CAPN2 activity in mdx muscles (only at 12 wks), (iv) autolyzed CAPN activity exclusively in mdx muscles, (v) lower expression of Capn1 and higher expression of Capn2 in mdx muscles; (vi) lower expression of Atp2a1 and Atp2a2 in mdx muscles, (vii) higher MMP (pre pro MMP2, pro MMP2, MMP2 and MMP9) activity in mdx muscles, (viii) MMP2 activity exclusively in mdx muscles at 12 wks, (ix) MMP9 activity exclusively in mdx muscles, (x) higher expression of Myog in mdx muscles at 12 wks, and (xi) lower expression of Myh (Myh7, Myh2, Myh1, Myh4) in mdx muscles, particularly Myh7 and Myh2. The collection of our results provides valuable information for a better characterization of mdx pathology phenotype. Histol Histopathol 35, 203-216 (2020)
Key words: Mdx mouse, Muscular dystrophy, Calpain, Calcium, Matrix metalloprotease
DOI: 10.14670/HH-18-145