C1q ablation exacerbates amyloid deposition: A study in a transgenic mouse model of ATTRV30M amyloid neuropathy

PLoS One. 2017 Apr 13;12(4):e0175767. doi: 10.1371/journal.pone.0175767. eCollection 2017.

Abstract

ATTRV30M amyloid neuropathy is a lethal autosomal dominant sensorimotor and autonomic neuropathy, caused by deposition of amyloid fibrils composed of aberrant transthyretin (TTR). Ages of onset and penetrance exhibit great variability and genetic factors have been implicated. Complement activation co-localizes with amyloid deposits in amyloidotic neuropathy and is possibly involved in the kinetics of amyloidogenesis. A candidate gene approach has recently identified C1q polymorphisms to correlate with disease onset in a Cypriot cohort of patients with ATTRV30M amyloid neuropathy. In the current study we use a double transgenic mouse model of ATTRV30M amyloid neuropathy in which C1q is ablated to elucidate further a possible modifier role for C1q. Amyloid deposition is found to be increased by 60% in the absence of C1q. Significant up regulation is also recorded in apoptotic and cellular stress markers reflecting extracellular toxicity of pre-fibrillar and fibrillar TTR. Our data further indicate that in the absence of C1q there is marked reduction of macrophages in association with amyloid deposits and thus less effective phagocytosis of TTR.

MeSH terms

  • Amyloid / metabolism*
  • Amyloid Neuropathies, Familial / genetics
  • Amyloid Neuropathies, Familial / metabolism
  • Amyloid Neuropathies, Familial / pathology*
  • Animals
  • Apoptosis
  • Complement C1 / deficiency*
  • Disease Models, Animal
  • Female
  • Humans
  • Mice
  • Mice, Transgenic
  • Mutation
  • Prealbumin / genetics*
  • Prealbumin / metabolism

Substances

  • Amyloid
  • Complement C1
  • Prealbumin

Grants and funding

The work was supported by a grant from the Cyprus Research Promotion Foundation ΥΓΕΙΑ/ΒΙΟΣ/0308(ΒΙΕ)/02 (http://www.research.org.cy/).