Higher MMP2 abundance and gelatinolytic activity in 28- & 70-d mdx compared with wild-type mice is alleviated in mdx mice with pre-natal taurine supplementation.

Higher MMP2 abundance and gelatinolytic activity in 28- & 70-d mdx compared with wild-type mice is alleviated in mdx mice with pre-natal taurine supplementation. Am J Physiol Cell Physiol. 2020 Mar 25;: Authors: Ren X, Xu H, Barker RG, Lamb GD, Murphy RM Abstract Duchenne muscular dystrophy (DMD) is a severe, progressive muscle wasting disorder that leads to early death. The mdx mouse is a naturally occurring mutant model for DMD. It lacks dystrophin and displays peak muscle cell necrosis at ~28 days (D28), but in contrast to DMD, mdx mice experience muscle regeneration by D70. We hypothesised that matrix metalloproteinase-2 (MMP2) and/or MMP9 play key roles in the degeneration / regeneration phases in mdx mice. MMP2 abundance in muscle homogenates, measured by calibrated western blotting and activity, measured by zymogram, were lower at D70 compared with D28 in both mdx and wild-type (WT) mice. Importantly, MMP2 abundance was higher in both D28 and D70 mdx mice than in age-matched WT mice. The higher MMP2 abundance was not due to infiltrating macrophages, because MMP2 content was still higher in isolated muscle fibers where most macrophages had been removed. Pre-natal supplementation with the amino acid taurine, which improved muscle strength in D28 mdx mice, produced ~2-fold lower MMP2 activity, indicating that increased MMP2 abundance is not required when muscle damage is attenuated. There was no difference in MMP9 abundance b...
Source: American Journal of Physiology. Cell Physiology - Category: Cytology Authors: Tags: Am J Physiol Cell Physiol Source Type: research