Exacerbation of erythropoietic protoporphyria by hyperthyroidism

Iodine-131 intervention in hyperthyroidism with hepatic insufficiency: Metabolomic evaluation

Hyperthyroidism, often accompanied by hepatic insufficiency (HI), poses significant clinical challenges, highlighting the necessity for identifying optimal treatment strategies and early diagnostic biomarkers to improve patient outcomes. This study aimed to determine the optimal iodine-131 (131I) intervention dose for alleviating hyperthyroidism with HI and to identify serum metabolic biomarkers for early diagnosis using UPLC-Q/TOF-MS technology. A mouse model for early 131I intervention was established to monitor changes in physiological response, body weight, fur condition, thyroid, and liver function. Metabolite identification was achieved through UPLC-Q/TOF-MS and further analyzed via MetaboAnalyst. Six biomarkers were identified and subjected to ROC analysis. Early intervention with 80 μCi 131I per gram of thyroid tissue effectively controlled hyperthyroidism and improved liver function. Metabolomics analysis uncovered 63 differentially abundant metabolites, six of which (L-kynurenine, Taurochenodesoxycholic acid, Glycocholic acid, Phytosphingosine, Tryptamine, and Betaine) were identified as early warning biomarkers. Post-intervention, these biomarkers progressively returned to normal levels. This study demonstrates the efficacy of UPLC-Q/TOF-MS in identifying metabolic biomarkers for early diagnosis of hyperthyroidism with HI and highlights the therapeutic potential of early 131I intervention in normalizing these biomarkers.

Iron in Porphyrias: Friend or Foe?

Iron is a trace element that is important for many vital processes, including oxygen transport, oxidative metabolism, cellular proliferation, and catalytic reactions. Iron supports these functions mainly as part of the heme molecule. Heme synthesis is an eight-step process which, when defective at the level of one of the eight enzymes involved, can cause the development of a group of diseases, either inherited or acquired, called porphyrias. Despite the strict link between iron and heme, the role of iron in the different types of porphyrias, particularly as a risk factor for disease development/progression or as a potential therapeutic target or molecule, is still being debated, since contrasting results have emerged from clinical observations, in vitro studies and animal models. In this review we aim to deepen such aspects by drawing attention to the current evidence on the role of iron in porphyrias and its potential implication. Testing for iron status and its metabolic pathways through blood tests, imaging techniques or genetic studies on patients affected by porphyrias can provide additional diagnostic and prognostic value to the clinical care, leading to a more tailored and effective management.

Homeostasis of iron and hepcidin in erythropoietic protoporphyria

BACKGROUND

Erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP) are genetic abnormalities of heme synthesis that result in excess production of protoporphyrin and that manifest as severe photosensitivity. These disorders are often associated with iron deficiency anaemia (IDA). Our aim was to determine whether hepcidin is increased in EPP/XLP patients, resulting in decreased enteral iron absorption and IDA.

MATERIAL AND METHODS

Eight subjects with EPP, one with XLP and nine controls had baseline blood and urine samples collected, and thereafter were given oral ferrous sulphate (660 mg). Post-iron blood and urine samples were collected at 2, 4, 6 and 8 h. Blood counts, serum cytokines, ferritin and iron studies were analysed at baseline. Serum iron studies, serum and urine hepcidin, and erythropoietin (Epo) were analysed at baseline and subsequent time points.

RESULTS

At baseline, EPP-XLP subjects had lower mean blood haemoglobin (13·9/15·3 g/dL) and serum ferritin (31·6/115 ng/mL) than controls. Serum iron levels increased markedly in both cohorts. Mean serum and urine hepcidin levels were significantly lower in the EPP-XLP group at 4 and 8 h post-iron (serum - 4 h, 3·79/26·6, 8 h, 5·79/34·6 nM; urine - 4 h, 0·85/2·50, 8 h, 1·44/6·63 nM/mM creatinine). Serum cytokines and Epo were normal and not different between groups.

CONCLUSIONS

We conclude that serum and urine hepcidin are not inappropriately increased in EPP/XLP subjects at baseline and do not increase over time as serum iron increases after oral ferrous sulphate. Levels of serum cytokines and Epo are normal in EPP/XLP. The molecular basis for the iron-deficient phenotype in EPP/XLP remains unknown.