AAV-mediated cardiac gene transfer of wild-type desmin in mouse models for recessive desminopathies

Abstract

Mutations in the human desmin gene cause autosomal-dominant and recessive cardiomyopathies and myopathies with marked phenotypic variability. Here, we investigated the effects of adeno-associated virus (AAV)-mediated cardiac wildtype desmin expression in homozygous desmin knockout (DKO) and homozygous R349P desmin knockin (DKI) mice. These mice serve as disease models for two subforms of autosomal-recessive desminopathies, the former for the one with a complete lack of desmin protein and the latter for the one with solely mutant desmin protein expression in conjunction with protein aggregation pathology in striated muscle. Two-month-old mice were injected with either a single dose of 5 × 10 12 AAV9-hTNT2-mDes (AAV-Des) vector genomes or NaCl as control. One week after injection, mice were subjected to a forced swimming exercise protocol for 4 weeks. Cardiac function was monitored over a period of 15 month after injection and before the mice were sacrificed for biochemical and morphological analysis. AAV-mediated cardiac expression of wildtype desmin in both the homozygous DKO and DKI backgrounds reached levels seen in wild-type mice. Notably, AAV-Des treated DKO mice showed a regular subcellular distribution of desmin as well as a normalization of functional and morphological cardiac parameters. Treated DKI mice, however, showed an aberrant subcellular localization of desmin, unchanged functional cardiac parameters, and a trend toward an increased cardiac fibrosis. In conclusion, the effect of a high-dose AAV9-based desmin gene therapy is highly beneficial for the heart in DKO animals, but not in DKI mice.

The desmin mutation R349P increases contractility and fragility of stem cell-generated muscle micro-tissues

“…Our observation that cell-generated contractile stresses during tetanic stimulation are sufficient to cause a mechanical disintegration of desmin-mutated micro-tissues is consistent with studies in desmin-mutated mice that link high-impact physical exercise to accelerated cardiac tissue damage (50, 51). Furthermore, the slow structural disintegration of desmin-mutated micro-tissues over time without noticeable loss in total force up until late disease stages mimics the clinical course of the disease in humans.…”

Desmin Knock-Out Cardiomyopathy: A Heart on the Verge of Metabolic Crisis

“…One group of upregulated proteins was related to redox reactions and oxidative stress, and comprised glutathione peroxidase 3 (Gpx3), thioredoxin (Txn), thioredoxin domain-containing protein 5 (Txndc5), and protein disulfide-isomerase A4 (Pdia4). In keeping with the above mentioned upregulation of the term “extracellular matrix”, a second group consisting of vimentin (Vim), decorin (Dcn), and lumican (Lum) was significantly upregulated thus reflecting the previously and consistently documented increased interstitial fibrosis of left ventricular cardiac tissue in desmin knock-out mice [ 48 , 49 , 50 ]. In addition to the expected lack of desmin, two metabolism-related proteins, namely fructose-1,6-bisphosphatase isozyme 2 (Fbp2) and mitochondrial methionine-R-sulfoxide reductase B2 (Msrb2), were downregulated.…”

The lncRNA CASC9 alleviates lipopolysaccharide-induced acute kidney injury by regulating the miR-424-5p/TXNIP pathway

“…Thirty male mice (6 weeks old) were randomly divided into three groups (n = 10/group): control group, LPS group, and LPS+CASC9 overexpression group. Mice in the control and LPS groups were injected with CASC9 negative-control adeno-associated virus and those in the LPS+CASC9 group were injected with lncRNA CASC9 overexpression adeno-associated virus (5 × 10 12 vg/mouse, 100 µL) 29 , 30 via the tail vein twice a week for 3 consecutive weeks. All adeno-associated viruses were prepared by Genechem Co., Ltd. (Shanghai, China).…”