| First Author | Branyan K | Year | 2023 |
| Journal | Matrix Biol | Volume | 115 |
| Pages | 48-70 | PubMed ID | 36435425 |
| Mgi Jnum | J:338943 | Mgi Id | MGI:7410708 |
| Doi | 10.1016/j.matbio.2022.11.007 | Citation | Branyan K, et al. (2022) Elevated TGFbeta Signaling Contributes to Cerebral Small Vessel Disease in Mouse Models of Gould Syndrome. Matrix Biol |
| abstractText | BACKGROUND: Cerebral small vessel disease (CSVD) is a leading cause of stroke and vascular cognitive impairment and dementia. Studying monogenic CSVD can reveal pathways that are dysregulated in common sporadic forms of the disease and may represent therapeutic targets. Mutations in collagen type IV alpha 1 (COL4A1) and alpha 2 (COL4A2) cause highly penetrant CSVD as part of a multisystem disorder referred to as Gould syndrome. COL4A1 and COL4A2 form heterotrimers [a1alpha1alpha2(IV)] that are fundamental constituents of basement membranes. However, their functions are poorly understood and the mechanism(s) by which COL4A1 and COL4A2 mutations cause CSVD are unknown. METHODS: We used histological, molecular, genetic, pharmacological, and in vivo imaging approaches to characterize central nervous system (CNS) vascular pathologies in Col4a1 mutant mouse models of monogenic CSVD to provide insight into underlying pathogenic mechanisms. RESULTS: We describe developmental CNS angiogenesis abnormalities characterized by impaired retinal vascular outgrowth and patterning, increased numbers of mural cells with abnormal morphologies, altered contractile protein expression in vascular smooth muscle cells (VSMCs) and age-related loss of arteriolar VSMCs in Col4a1 mutant mice. Importantly, we identified elevated TGFbeta signaling as a pathogenic consequence of Col4a1 mutations and show that genetically suppressing TGFbeta signaling ameliorated CNS vascular pathologies, including partial rescue of retinal vascular patterning defects, prevention of VSMC loss, and significant reduction of intracerebral hemorrhages in Col4a1 mutant mice aged up to 8 months. CONCLUSIONS: This study identifies a novel biological role for collagen alpha1alpha1alpha2(IV) as a regulator of TGFbeta signaling and demonstrates that elevated TGFbeta signaling contributes to CNS vascular pathologies caused by Col4a1 mutations. Our findings suggest that pharmacologically suppressing TGFbeta signaling could reduce the severity of CSVD, and potentially other manifestations associated with Gould syndrome and have important translational implications that could extend to idiopathic forms of CSVD. |
