Post-Translational Modifications of p53 in Ferroptosis: Novel Pharmacological Targets for Cancer Therapy

Dexmedetomidine preconditioning attenuates ferroptosis in myocardial ischemia-reperfusion injury via α2 adrenergic receptor activation

Objective

Dexmedetomidine (Dex) is a potent agonist of the α2 adrenergic receptor that has been shown to possess sedative and hypnotic properties. Dex can protect against myocardial ischemia-reperfusion injury (MIRI) by inhibiting ferroptosis. However, these studies were based on Dex post-conditioning, and the role of α2 adrenergic receptors in this process is unclear. In this study, we investigated whether Dex preconditioning can prevent MIRI by attenuating ferroptosis and whether this effect depends on α2 adrenergic receptors in rats.

Methods

Male Sprague-Dawley rats were randomly assigned to five groups: sham (saline-treated), I/R (ischemia-exposed), Dex + I/R (Dex pre-treatment), Dex + Yoh + I/R (Dex and yohimbine pre-treatment), and Yoh + I/R (yohimbine pre-treatment). Cardiac function, myocardial infarction, and morphological changes were assessed. Transmission electron microscopy was used to analyze mitochondrial morphology. Ferroptosis-related indicators and lipid peroxidation were measured using western blotting and qRT-PCR.

Results

Our findings indicated that Dex preconditioning improved cardiac function, reduced infarct size and apoptosis, and inhibited ferroptosis in the rat myocardium after MIRI. These effects were associated with the upregulation of Nrf2, SLC7A11, and GPX4 expression, as well as the downregulation of Ferritin, TFR1, ACSL4, COX2, IL-1β, IL-6, and TNF-α expression. Importantly, yohimbine, an α2 adrenergic receptor antagonist, abolished these protective effects.

Conclusion

These results suggest that Dex preconditioning can prevent MIRI by attenuating ferroptosis via α2 adrenergic receptor activation and by modulating the Nrf2/SLC7A11/GPX4 pathway.

Ferroptosis: A new strategy for targeting Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a complex pathogenesis, which involves the formation of amyloid plaques and neurofibrillary tangles. Many recent studies have revealed a close association between ferroptosis and the pathogenesis of AD. Factors such as ferroptosis-associated iron overload, lipid peroxidation, disturbances in redox homeostasis, and accumulation of reactive oxygen species have been found to contribute to the pathological progression of AD. In this review, we explore the mechanisms underlying ferroptosis, describe the link between ferroptosis and AD, and examine the reported efficacy of ferroptosis inhibitors in treating AD. Finally, we discuss the potential challenges to ferroptosis inhibitors use in the clinic, enabling their faster use in clinical treatment.

Lipoxygenases at the Intersection of Infection and Carcinogenesis

The persisting presence of opportunistic pathogens like Pseudomonas aeruginosa poses a significant threat to many immunocompromised cancer patients with pulmonary infections. This review highlights the complexity of interactions in the host's defensive eicosanoid signaling network and its hijacking by pathogenic bacteria to their own advantage. Human lipoxygenases (ALOXs) and their mouse counterparts are integral elements of the innate immune system, mostly operating in the pro-inflammatory mode. Taking into account the indispensable role of inflammation in carcinogenesis, lipoxygenases have counteracting roles in this process. In addition to describing the structure-function of lipoxygenases in this review, we discuss their roles in such critical processes as cancer cell signaling, metastases, death of cancer and immune cells through ferroptosis, as well as the roles of ALOXs in carcinogenesis promoted by pathogenic infections. Finally, we discuss perspectives of novel oncotherapeutic approaches to harness lipoxygenase signaling in tumors.

A New Perspective in the Treatment of Ischemic Stroke: Ferroptosis

Ischemic stroke is a common neurological disease. Currently, there are no Food and Drug Administration-approved drugs that can maximize the improvement in ischemic stroke-induced nerve damage. Hence, treating ischemic stroke remains a clinical challenge. Ferroptosis has been increasingly studied in recent years, and it is closely related to the pathophysiological process of ischemic stroke. Iron overload, reactive oxygen species accumulation, lipid peroxidation, and glutamate accumulation associated with ferroptosis are all present in ischemic stroke. This article focuses on describing the relationship between ferroptosis and ischemic stroke and summarizes the relevant substances that ameliorate ischemic stroke-induced neurological damage by inhibiting ferroptosis. Finally, the problems in the treatment of ischemic stroke targeting ferroptosis are discussed, hoping to provide a new direction for its treatment.

Insight on Heterocycles as p53‐MDM2 Protein‐Protein Interaction Inhibitors: Molecular Mechanism for p53 Activation

Transcription factor p53, also known as tumor suppressor protein. Encoded by the TP53 gene, the guardian of genome p53 regulates many gene pathways. Nevertheless, the molecular mechanisms of p53 functioning have been known for a few decades, and the exact role of p53 in cancer therapy is unclear. Also, comprehensive literature on heterocycles as p53‐MDM2 protein‐protein interaction inhibitors is limited. This review covers the molecular mechanism for the p53‐MDM2 interaction and its inhibition by the heterocyclic small molecules. We hope the present comprehensive study will help to develop heterocycles as anticancer drugs that induce apoptosis in tumor cells.

Antioxidant Systems as Modulators of Ferroptosis: Focus on Transcription Factors

Ferroptosis is a type of programmed cell death that differs from apoptosis, autophagy, and necrosis and is related to several physio-pathological processes, including tumorigenesis, neurodegeneration, senescence, blood diseases, kidney disorders, and ischemia-reperfusion injuries. Ferroptosis is linked to iron accumulation, eliciting dysfunction of antioxidant systems, which favor the production of lipid peroxides, cell membrane damage, and ultimately, cell death. Thus, signaling pathways evoking ferroptosis are strongly associated with those protecting cells against iron excess and/or lipid-derived ROS. Here, we discuss the interaction between the metabolic pathways of ferroptosis and antioxidant systems, with a particular focus on transcription factors implicated in the regulation of ferroptosis, either as triggers of lipid peroxidation or as ferroptosis antioxidant defense pathways.

Novel Insights on Ferroptosis Modulation as Potential Strategy for Cancer Treatment: When Nature Kills

Significance: The multifactorial nature of the mechanisms implicated in cancer development still represents a major issue for the success of established antitumor therapies. The discovery of ferroptosis, a novel form of programmed cell death distinct from apoptosis, along with the identification of the molecular pathways activated during its execution, has led to the uncovering of novel molecules characterized by ferroptosis-inducing properties. Recent advances: As of today, the ferroptosis-inducing properties of compounds derived from natural sources have been investigated and interesting findings have been reported both in vitro and in vivo. Critical Issues: Despite the efforts made so far, only a limited number of synthetic compounds have been identified as ferroptosis inducers, and their utilization is still limited to basic research. In this review, we analyzed the most important biochemical pathways involved in ferroptosis execution, with particular attention to the newest literature findings on canonical and non-canonical hallmarks, together with mechanisms of action of natural compounds identified as novel ferroptosis inducers. Compounds have been classified based on their chemical structure, and modulation of ferroptosis-related biochemical pathways has been reported. Future Directions: The outcomes herein collected represent a fascinating starting point from which to take hints for future drug discovery studies aimed at identifying ferroptosis-inducing natural compounds for anticancer therapies. Antioxid. Redox Signal. 40, 40-85.

The regulatory effects of p53 on the typical and atypical ferroptosis in the pathogenesis of osteosarcoma: A systematic review

Study background: As a rare condition, osteosarcoma affects approximately 3% of all cancer patients. Its exact pathogenesis remains largely unclear. The role of p53 in up- and down-regulating atypical and typical ferroptosis in osteosarcoma remains unclear. The primary objective of the present study is investigating the role of p53 in regulating typical and atypical ferroptosis in osteosarcoma. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and the Patient, Intervention, Comparison, Outcome, and Studies (PICOS) protocol were used in the initial search. The literature search was performed in six electronic databases, including EMBASE, Cochrane library of trials, Web of Science, PubMed, Google Scholar, and Scopus Review, using keywords connected by Boolean operators. We focused on studies that adequately defined patient profiles described by PICOS. Results and discussion: We found that p53 played fundamental up- and down-regulatory roles in typical and atypical ferroptosis, resulting in either advancement or suppression of tumorigenesis, respectively. Direct and indirect activation or inactivation of p53 downregulated its regulatory roles in ferroptosis in osteosarcoma. Enhanced tumorigenesis was attributed to the expression of genes associated with osteosarcoma development. Modulation of target genes and protein interactions, especially SLC7A11, resulted in enhanced tumorigenesis. Conclusion: Typical and atypical ferroptosis in osteosarcoma were regulatory functions of p53. The activation of MDM2 inactivated p53, leading to the downregulation of atypical ferroptosis, whereas activation of p53 upregulated typical ferroptosis. Further studies should be performed on the regulatory roles of p53 to unmask its possible clinical applications in the management of osteosarcoma.

The effect of narcotics on ferroptosis-related molecular mechanisms and signalling pathways

Ferroptosis is a novel programmed cell death form characterized by iron-mediated reactive oxygen species-induced lipid peroxidation and subsequent cell damage that is distinct from apoptosis, necroptosis, pyroptosis, and autophagy. Most studies on ferroptosis are based on its function and mechanism, but there have been relatively few studies on the effects of drugs, especially anaesthetics, on ferroptosis. Therefore, we summarized the recent literature on the effects of anaesthetics on ferroptosis to understand the underlying mechanism. In particular, we focused on the targets of various anaesthetics in different mechanisms of ferroptosis and the effects of ferroptosis induction or inhibition by narcotics on various diseases. The aims of this review are to provide a relatively reasonable drug regimen for clinicians, to explore potential ferroptosis protection drugs and targets, to reduce perioperative complications and to improve the postoperative performance of patients, especially those who are critically ill.

Polyphenol-Rich Date Palm Fruit Seed (Phoenix Dactylifera L.) Extract Inhibits Labile Iron, Enzyme, and Cancer Cell Activities, and DNA and Protein Damage

Date palm fruit seed (Phoenix dactylifera L.) extract (DSE), an under-utilized resource, is a rich source of polyphenols with high potency for disease prevention and antioxidative activities. For the first time, the present study demonstrated that DSE inhibits labile iron activity and DNA and BSA damage and inhibits acetylcholinesterase and tyrosinase activities. Moreover, DSE reduces the proliferation of hepatic, colorectal, and breast cancer cells dose-dependently through apoptotic mechanisms. Furthermore, DSE significantly suppressed the expression of both BCl-2 and P21 genes and increased the P53 expression level when compared with the untreated cells and the 5-FU treated cells. These findings suggest a strong potential for DSE in protecting against the iron-catalyzed ferroptosis that results in programmed cell death. The results also confirm the efficacy of DSE against cancer cells. Therefore, DSE constitutes a valuable candidate for developing functional foods and for natural compound-based chemotherapy for the pharmaceutical and nutraceutical industries.

The potential interplay between G-quadruplex and p53: their roles in regulation of ferroptosis in cancer

Ferroptosis is a novel form of regulated cell death trigged by various biological processes, and p53 is involved in different ferroptosis regulations and functions as a crucial regulator. Both DNA and RNA can fold into G-quadruplex in GC-rich regions and increasing shreds of evidence demonstrate that G-quadruplexes have been associated with some important cellular events. Investigation of G-quadruplexes is thus vital to revealing their biological functions. Specific G-quadruplexes are investigated to discover new effective anticancer drugs. Multiple modulations have been discovered between the secondary structure G-quadruplex and p53, probably further influencing the ferroptosis in cancer. G-quadruplex binds to ferric iron-related structures directly and may affect the p53 pathways as well as ferroptosis in cancer. In addition, G-quadruplex also interacts with p53 indirectly, including iron-sulfur cluster metabolism, telomere homeostasis, lipid peroxidation, and glycolysis. In this review, we summarized the latent interplay between G-quadruplex and p53 which focused mainly on ferroptosis in cancer to provide the potential understanding and encourage future studies.