Reduced hepcidin expression enhances iron overload in patients with HbE/β-thalassemia: Α comparative cross-sectional study

Genetic Correlation of HBB, HFE and HAMP Genes to Endocrinal Complications in Egyptian Beta Thalassemia Major Patients

Iron loading is regarded as the primary cause of endocrine abnormalities in thalassemia major patients. Thus, the purpose of the current research was to explore the impact of thalassemia genotypes, hepcidin antimicrobial peptide (HAMP) and hereditary hemochromatosis (HFE) gene variants, and hepcidin expression on serum ferritin and endocrinal complications in thalassemia patients. The study comprised fifty beta-thalassemia cases and fifty age- and sex-matched controls. Genotyping of the Beta-globin gene (HBB), HAMP, and exon 2 of the HFE gene was performed using Sanger sequencing. C282Y (c.845G > A) variant of the HFE gene was determined by PCR-RFLP. Hepcidin mRNA expression was assessed by qRT-PCR. Biochemical and hormonal studies were done for all patients. Hypogonadism and short stature were found in 56% and 20% of the investigated cases, respectively. Molecular studies reported a statistically higher frequency of the HAMP variant c.-582A > G in thalassemic patients than controls. Significant downregulation of hepcidin expression was found in cases compared to healthy subjects that was significantly associated with short stature. Considering the thalassemia alleles, the IVSI.1G > A (β0) allele was statistically related to hypogonadism. Our results proposed that thalassemia genotypes and downregulated hepcidin expression were the potential risk factors for endocrinopathies in our cases. We also demonstrated an increased incidence of the HAMP promoter variant c.- 582A > G that might have a role in the pathogenesis of iron overload in thalassemic cases. Significant downregulation of hepcidin expression, that contributes to increased iron burden, could be used as a future therapeutic target in these patients.

Active Components of Pueraria lobata through the MAPK/ERK Signaling Pathway Alleviate Iron Overload in Alcoholic Liver Disease

OBJECTIVE

To delve into the primary active ingredients and mechanism of Pueraria lobata for alleviating iron overload in alcoholic liver disease.

METHODS

Pueraria lobata's potential targets and signaling pathways in treating alcohol-induced iron overloads were predicted using network pharmacology analysis. Then, animal experiments were used to validate the predictions of network pharmacology. The impact of puerarin or genistein on alcohol-induced iron accumulation, liver injury, oxidative stress, and apoptosis was assessed using morphological examination, biochemical index test, and immunofluorescence. Key proteins implicated in linked pathways were identified using RT-qPCR, western blot analysis, and immunohistochemistry.

RESULTS

Network pharmacological predictions combined with animal experiments suggest that the model group compared to the control group, exhibited activation of the MAPK/ERK signaling pathway, suppression of hepcidin expression, and aggravated iron overload, liver damage, oxidative stress, and hepatocyte death. Puerarin and genistein, the active compounds in Pueraria lobata, effectively mitigated the aforementioned alcohol-induced effects. No statistically significant disparities were seen in the effects above between the two groups receiving drug therapy.

CONCLUSION

This study preliminarily demonstrated that puerarin and genistein in Pueraria lobata may increase hepcidin production to alleviate alcohol-induced iron overload by inhibiting the MAPK/ERK signaling pathway.

Activation of STAT and SMAD Signaling Induces Hepcidin Re-Expression as a Therapeutic Target for β-Thalassemia Patients

Iron homeostasis is regulated by hepcidin, a hepatic hormone that controls dietary iron absorption and plasma iron concentration. Hepcidin binds to the only known iron export protein, ferroportin (FPN), which regulates its expression. The major factors that implicate hepcidin regulation include iron stores, hypoxia, inflammation, and erythropoiesis. When erythropoietic activity is suppressed, hepcidin expression is hampered, leading to deficiency, thus causing an iron overload in iron-loading anemia, such as β-thalassemia. Iron overload is the principal cause of mortality and morbidity in β-thalassemia patients with or without blood transfusion dependence. In the case of thalassemia major, the primary cause of iron overload is blood transfusion. In contrast, iron overload is attributed to hepcidin deficiency and hyperabsorption of dietary iron in non-transfusion thalassemia. Beta-thalassemia patients showed marked hepcidin suppression, anemia, iron overload, and ineffective erythropoiesis (IE). Recent molecular research has prompted the discovery of new diagnostic markers and therapeutic targets for several diseases, including β-thalassemia. In this review, signal transducers and activators of transcription (STAT) and SMAD (structurally similar to the small mothers against decapentaplegic in Drosophila) pathways and their effects on hepcidin expression have been discussed as a therapeutic target for β-thalassemia patients. Therefore, re-expression of hepcidin could be a therapeutic target in the management of thalassemia patients. Data from 65 relevant published experimental articles on hepcidin and β-thalassemia between January 2016 and May 2021 were retrieved by using PubMed and Google Scholar search engines. Published articles in any language other than English, review articles, books, or book chapters were excluded.