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DOI: 10.1055/s-0043-1776760
The Hepatic Porphyrias: Revealing the Complexities of a Rare Disease
Funding This study was funded by the U.S. Department of Health and Human Services, National Institute of Diabetes and Digestive and Kidney Diseases, NIH grant no. 1R01DK124412 to Kari Nejak-Bowen.
Abstract
The porphyrias are a group of metabolic disorders that are caused by defects in heme biosynthesis pathway enzymes. The result is accumulation of heme precursors, which can cause neurovisceral and/or cutaneous photosensitivity. Liver is commonly either a source or target of excess porphyrins, and porphyria-associated hepatic dysfunction ranges from minor abnormalities to liver failure. In this review, the first of a three-part series, we describe the defects commonly found in each of the eight enzymes involved in heme biosynthesis. We also discuss the pathophysiology of the hepatic porphyrias in detail, covering epidemiology, histopathology, diagnosis, and complications. Cellular consequences of porphyrin accumulation are discussed, with an emphasis on oxidative stress, protein aggregation, hepatocellular cancer, and endothelial dysfunction. Finally, we review current therapies to treat and manage symptoms of hepatic porphyria.
Publication History
Article published online:
16 November 2023
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