Reduction of iron toxicity in the heart of iron-overloaded mice with natural compounds

Herbal medicines provide regulation against iron overload in cardiovascular diseases: Informing future applications

ETHNOPHARMACOLOGICAL RELEVANCE

Iron is an essential micronutrient for maintaining physiological activities, especially for highly active cardiomyocytes. Inappropriate iron overload or deficiency has a significant impact on the incidence and severity of cardiovascular diseases (CVD). Iron overload exerts potentially deleterious effects on doxorubicin (DOX) cardiomyopathy, atherosclerosis, and myocardial ischemia-reperfusion injury (MI/RI) by participating in lipid peroxides production. Notably, iron overload-associated cell death has been defined as a possible mechanism for ferroptosis. At present, some traditional herbal medicines and extracts have been included in the study of regulating iron overload and the subsequent therapeutic effect on CVD.

AIM OF THE STUDY

To give an outline of iron metabolism and ferroptosis in cardiomyocytes and to focus on herbal medicines and extracts to prevent iron overload in CVD.

MATERIALS AND METHODS

Literature information was systematically collected from ScienceDirect, PubMed, Google Scholar, Web of Science, China National Knowledge Infrastructure, WanFang data, as well as classic books and clinical reports.

RESULTS

After understanding the mechanism of iron overload on CVD, this paper reviews the therapeutic function of various herbal medicines in eliminating iron overload in CVD. These include Chinese herbal compound prescriptions (Salvia miltiorrhiza injection, Gegen Qinlian decoction, Tongxinluo, Banxia-Houpu decoction), plant extracts, phenylpropanoids, flavonoids, terpenoids, and polyphenols. Among them, flavonoids are considered to be the most promising compounds because of their prominent iron chelation. Mechanically, these herbal medicines act on the Nrf2 signaling pathway, AMPK signaling pathway, and KAT5/GPX4 signaling pathway, thereby attenuating iron overload and lipid peroxidation in CVD.

CONCLUSION

Our review provides up-to-date information on herbal medicines that exert cardiovascular protective effects by modulating iron overload and ferroptosis. These herbal medicines hold promise as a template for preventing iron overload in CVD.

Iron overload induced submandibular glands toxicity in gamma irradiated rats with possible mitigation by hesperidin and rutin

BACKGROUND

Radiation triggers salivary gland damage and excess iron accumulates in tissues induces cell injury. Flavonoids are found in some fruits and are utilized as potent antioxidants and radioprotective agents. This study aimed to evaluate the antioxidant and anti-inflammatory effects of hesperidin and rutin on gamma radiation and iron overload induced submandibular gland (SMG) damage and to evaluate their possible impact on mitigating the alteration in mTOR signaling pathway and angiogenesis.

METHODS

Forty-eight adult male Wistar albino rats were randomly assigned to six groups: group C received a standard diet and distilled water; group H received hesperidin at a dose of 100 mg/kg; four times a week for four weeks; group U received rutin at a dose of 50 mg/kg; three times a week for three weeks; group RF received a single dose (5 Gy) of gamma radiation followed by iron at a dose of 100 mg/kg; five times a week for four weeks; group RFH received radiation and iron as group RF and hesperidin as group H; group RFU received radiation and iron as group RF and rutin as group U. SMG specimens from all groups were removed at the end of the experiment; and some were used for biochemical analysis, while others were fixed for histological and immunohistochemical examination.

RESULTS

In the RF group, several genes related to antioxidants (Nrf-2 and SOD) and DNA damage (BRCA1) were significantly downregulated, while several genes related to inflammation and angiogenesis (TNFα, IL-1β and VEGF) and the mTOR signaling pathway (PIK3ca, AKT and mTOR) were significantly upregulated. Acinar cytoplasmic vacuolation, nuclear pyknosis, and interacinar hemorrhage with distinct interacinar spaces were observed as histopathological changes in SMGs. The duct system suffered significant damage, eventually degenerating entirely as the cells were shed into the lumina. VEGF and NF-κB were also significantly overexpressed. Hesperidin and rutin cotreatment generated partial recovery as indicated by significant upregulation of Nrf-2, SOD and BRCA1 and considerable downregulation of TNF-α, IL-1β, VEGF, PIK3ca, AKT, and mTOR. Although some acini and ducts continued to deteriorate, most of them had a normal appearance. There was a notable decrease in the expression of VEGF and NF-κB.

CONCLUSIONS

In γ-irradiated rats with iron overload, the administration of hesperidin and rutin may mitigate salivary gland damage.

Vanillin serves as a potential substitute for chemical chelator desferal in iron-overloaded mice

PURPOSE

Iron toxicity occurs under iron-overloaded settings, such as a high iron diet and blood transfusion, and damages important organs. Vanillin has been proven to have potential iron chelation capability. Given the negative effects of commonly used iron chelators like deferoxamine (DFO), we sought to examine the iron chelation potency of vanillin and evaluate its potential effect in the treatment of iron overload-related disorders.

METHODS

42 male NMRI mice were prepared for this purpose, and except for the negative control group, iron overload conditions were generated in them by injecting iron. Then normal saline (as a control), vanillin, and DFO (n = 7) were subsequently given to iron-overloaded mice. In the following, the activity of antioxidant enzymes catalase and superoxide dismutase were measured in the blood serum, brain, kidney, spleen, lung, and liver tissues of mice. Furthermore, the level of lipid peroxidation was determined by measuring the amount of malondialdehyde. Also, Perl's and H&E staining were used to examine the physiopathology changes of tissues.

FINDINGS

Vanillin, a natural antioxidant compound, outperformed deferoxamine, a chemical iron chelator. Along with a decrease in iron content, the activity of catalase and superoxide dismutase enhanced in the iron-overloaded groups that were treated with vanillin. The level of lipid peroxidation was also declined in the iron-overloaded mice receiving vanillin.

CONCLUSION

Vanillin can be used as a suitable substitute for chemical chelators with fewer side effects and equivalent efficiency. We encourage the use of this compound as a natural iron chelator following performing additional safety and efficacy studies.

Research progress on the role of ferroptosis in cardiovascular disease

The cardiovascular disease pathogenesis is extremely complex and seriously threatens human health. Cardiomyocyte death plays a significant role in cardiovascular disease occurrence and development. In addition to the previously revealed modes of cell death (apoptosis, autophagy, and pyroptosis), ferroptosis is highly related to the development of cardiovascular diseases, including arrhythmia, atherosclerosis, and myocardial ischemia/reperfusion. Ferroptosis is a novel cell death pathway driven by lipid peroxidation and iron overload. Lipid, amino acid, and iron metabolism regulate the ferroptosis pathway. Small molecule compounds (iron chelators, antioxidants, and ferroptosis inhibitors) and genetic programming can alleviate or prevent cardiovascular disease by inhibiting the ferroptosis pathway. Ferroptosis plays a key role in various cardiovascular disease occurrence and development, and inhibiting ferroptosis in cardiomyocytes is expected to become a feasible treatment method. In this mini-review, we systematically summarize the molecular mechanisms of ferroptosis in different cardiovascular diseases, delineate the regulatory network between ferroptosis and cardiovascular diseases, and highlight its potential therapeutic targets.

The natural iron chelators' ferulic acid and caffeic acid rescue mice's brains from side effects of iron overload

Studies have shown that iron accumulation in the brain leads to neurogenic disorders. Novel iron chelating agents such as natural remedies are useful to decrease the side effects of iron in the brain. In addition, flavones and polyphenols are capable of chelating metals. In the current study, we evaluated the iron chelating capacity of ferulic acid and caffeic acid in the brain tissues of iron-overloaded mice. The mice received iron dextran intraperitoneally four times a week for 6 weeks. Next, blood samples were taken from the mice. In addition, brain tissues were excised for tissue staining as well as total iron and catalase (CAT) activity assessment. Ferulic acid and caffeic acid significantly decreased iron content in both brain and serum samples. Ferulic acid decreased iron by 50 and 51% more than the iron dextran-treated mice and by 43 and 2% more than desferal (DFO)-treated mice in serum and brain, respectively. In addition, caffeic acid reduced iron 57% more than the iron-treated group and 49 and 2% more than the desferal-treated group in the serum and brain, respectively. The catalase activity decreased with the increase in iron. By administering natural compounds, the catalase activity was increased equal to that of the control group. Thus, ferulic acid and caffeic acid might be possible natural iron chelators for brain iron overload therapy.