Title:Alport Syndrome: A Comprehensive Review on Genetics, Pathophysiology, Histology, Clinical and Therapeutic Perspectives
Volume: 28
Issue: 27
Author(s): Ana Luisa Pedrosa, Letícia Bitencourt, Rafaela Moreira Paranhos, Cristiana Afonso Leitáo, Guilherme Costa Ferreira and Ana Cristina Simões e Silva*
Affiliation:
- Interdisciplinary Laboratory of Medical Investigation, Faculty of Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG,Brazil
Keywords:
Alport syndrome, gene mutations, glomerular basal membrane, collagen chains, podocytopathy, renin
angiotensin system, angiotensin converting enzyme inhibitors, angiotensin receptor blockers.
Abstract:
Background: Alport syndrome (AS) is a disease caused by mutations in
COL4A3, COL4A4 or COL4A5, the genes that encode distinct chains of type IV collagen.
The vast majority of cases present as an inherited disorder, although de novo mutations
are present in around 10% of the cases.
Methods: This non-systematic review summarizes recent evidence on AS. We discuss
the genetic and pathophysiology of AS, clinical manifestations, histopathology, diagnostic
protocols, conventional treatment and prognostic markers of the disease. In addition,
we summarize experimental findings with novel therapeutic perspectives for AS.
Results: The deficient synthesis of collagen heterotrimers throughout the organism leads
to impaired basement membranes (BM) in several organs. As a result, the disease manifests
in a wide range of conditions, particularly renal, ocular and auricular alterations.
Moreover, leiomyomatosis and vascular abnormalities may also be present as atypical
presentations. In this framework, diagnosis can be performed based on clinical evaluation,
skin or renal biopsy and genetic screening, the latter being the gold standard. There
are no formally approved treatments for AS, even though therapeutic options have been
described to delay disease progression and increase life expectancy. Novel therapeutic targets
under pre-clinical investigation included paricalcitol, sodium-glucose co-transporter-
2 inhibitors, bardoxolone methyl, anti-microRNA-21 oligonucleotides, recombinant
human pentraxin-2, lysyl oxidase-like-2 blockers, hydroxypropyl-b-cyclodextrin,
sodium 4-phenylbutyrate and stem cell therapy.
Conclusion: AS is still a greatly under and misdiagnosed disorder. The pathophysiology
is still not fully understood and genetics of the disease also have some gaps. Up to know,
there is no specific and effective treatment for AS. Further studies are necessary to establish
novel and effective therapeutic protocols.
