The influence of microbiota on ferroptosis in intestinal diseases

Current knowledge of ferroptosis in the pathogenesis and prognosis of oral squamous cell carcinoma

Therapeutic strategies are the hot-spot issues in treating patients with advanced oral squamous cell carcinoma (OSCC). Mounting studies have proved that triggering ferroptosis is one of the promising targets for OSCC management. In this study, we performed a first attempt to collect the current evidence on the proposed roles of ferroptosis in OSCC through a comprehensive review. Based on clinical data from the relevant studies within this topic, we found that ferroptosis-associated tumor microenvironment, ferroptosis-related genes (FRGs), and ferroptosis-related lncRNAs exhibited a potent prognostic value for OSCC patients. Mechanistically, experimental data revealed that the proliferation and tumorigenesis of OSCC might be associated with the inhibition of cellular ferroptosis through the activation of glutathione peroxidase 4 (GPX4) and adipocyte enhancer-binding protein 1 (AEBP1), suppression of glutathione (GSH) and Period 1 (PER1) expression, and modulation of specific non-coding RNAs (i.e., miR-520d-5p, miR-34c-3p, and miR-125b-5p) and their targeted proteins. Several specific interventions (i.e., Quisinostat, Carnosic acid, hyperbaric oxygen, melatonin, aqueous-soluble sporoderm-removed G. lucidum spore powder, and disulfiram/copper complex) were found to dramatically induce ferroptosis cell death of OSCC via multiple mechanisms. This review highlighted the pivotal role of ferroptosis in the pathogenesis and prognosis of OSCC. Future anticancer therapeutic strategies targeting ferroptosis and its associated molecules might provide a new insight for OSCC treatment.

Targeting ferroptosis in neuroimmune and neurodegenerative disorders for the development of novel therapeutics

Neuroimmune and neurodegenerative ailments impose a substantial societal burden. Neuroimmune disorders involve the intricate regulatory interactions between the immune system and the central nervous system. Prominent examples of neuroimmune disorders encompass multiple sclerosis and neuromyelitis optica. Neurodegenerative diseases result from neuronal degeneration or demyelination in the brain or spinal cord, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. The precise underlying pathogenesis of these conditions remains incompletely understood. Ferroptosis, a programmed form of cell death characterised by lipid peroxidation and iron overload, plays a pivotal role in neuroimmune and neurodegenerative diseases. In this review, we provide a detailed overview of ferroptosis, its mechanisms, pathways, and regulation during the progression of neuroimmune and neurodegenerative diseases. Furthermore, we summarise the impact of ferroptosis on neuroimmune-related cells (T cells, B cells, neutrophils, and macrophages) and neural cells (glial cells and neurons). Finally, we explore the potential therapeutic implications of ferroptosis inhibitors in diverse neuroimmune and neurodegenerative diseases.

Ferroptosis: a potential bridge linking gut microbiota and chronic kidney disease

Ferroptosis is a novel form of lipid peroxidation-driven, iron-dependent programmed cell death. Various metabolic pathways, including those involved in lipid and iron metabolism, contribute to ferroptosis regulation. The gut microbiota not only supplies nutrients and energy to the host, but also plays a crucial role in immune modulation and metabolic balance. In this review, we explore the metabolic pathways associated with ferroptosis and the impact of the gut microbiota on host metabolism. We subsequently summarize recent studies on the influence and regulation of ferroptosis by the gut microbiota and discuss potential mechanisms through which the gut microbiota affects ferroptosis. Additionally, we conduct a bibliometric analysis of the relationship between the gut microbiota and ferroptosis in the context of chronic kidney disease. This analysis can provide new insights into the current research status and future of ferroptosis and the gut microbiota.

Inhibition of ferroptosis: A new direction in the treatment of ulcerative colitis by traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a chronic idiopathic intestinal disease of unknown cause and has been classified as one of the modern intractable diseases by the World Health Organization (WHO). Ferroptosis, as an iron-ion-dependent mode of programmed cell death, is closely related to iron metabolism, lipid peroxidation, and imbalance of the antioxidant system, and plays an important role in the development of UC. In this paper, we will review the regulatory pathways of ferroptosis, the relationship between ferroptosis and the pathogenesis of UC, and the treatment of UC by TCM from the perspective of ferroptosis inhibition, and summarize the mechanism of action of the active ingredients of TCM and TCM compounds to improve UC through ferroptosis inhibition, and look forward to the prospect of the application of ferroptosis inhibition by TCM in the treatment of UC.

AIM OF THIS REVIEW

This paper aims to elucidate the mechanism of action of TCM active ingredients and TCM combinations in the treatment of UC by inhibiting ferroptosis. The active ingredients of TCM have the significant advantages of multi-targets and multi-pathways, and ferroptosis is the current research hotspot in the prevention and treatment of UC, so the inhibition of ferroptosis by TCM is a key direction for future research.

MATERIALS AND METHODS

The keywords "ferroptosis", "ulcerative colitis" and "TCM" were searched in Pubmed, CNKI, and Wed of Science databases. Papers related to clinical trials and pharmacological research up to August 2023 were screened for inclusion. Combined with the theory of TCM, we systematically summarized the effects of TCM active ingredients and TCM combinations in inhibiting ferroptosis and thus preventing UC.

RESULTS

A large number of studies have shown that TCM active ingredients and TCM combinations inhibit the inflammatory response and oxidative stress in the course of UC mainly by interfering with iron metabolism, correcting lipid metabolism and peroxidative accumulation, and regulating the processes of glutathione (GSH) and glutathione peroxidase 4 (GPX4), to improve colonic mucosal damage and promote the repair of colonic mucosal tissue.

CONCLUSION

Since the study of ferroptosis in UC is still in the exploratory stage, many issues still deserve attention in the future. This paper reviews the mechanism of ferroptosis inhibition by TCM active ingredients and TCM combinations to prevent and treat UC. In the future, we should also further increase the number of clinical experimental studies to explore whether more TCM medicines can play a therapeutic role in UC by inhibiting ferroptosis, and explore more pathways and genes targeting the inhibition of ferroptosis, to seek more TCM therapies for UC. We believe that the use of TCM active ingredients and TCM combinations to regulate ferroptosis is an important direction for future UC prevention and treatment.

Ferroptosis, Inflammation, and Microbiome Alterations in the Intestine in the Göttingen Minipig Model of Hematopoietic-Acute Radiation Syndrome

Hematopoietic acute radiation syndrome (H-ARS) involves injury to multiple organ systems following total body irradiation (TBI). Our laboratory demonstrated that captopril, an angiotensin-converting enzyme inhibitor, mitigates H-ARS in Göttingen minipigs, with improved survival and hematopoietic recovery, as well as the suppression of acute inflammation. However, the effects of captopril on the gastrointestinal (GI) system after TBI are not well known. We used a Göttingen minipig H-ARS model to investigate captopril's effects on the GI following TBI (60Co 1.79 or 1.80 Gy, 0.42-0.48 Gy/min), with endpoints at 6 or 35 days. The vehicle or captopril (0.96 mg/kg) was administered orally twice daily for 12 days, starting 4 h post-irradiation. Ilea were harvested for histological, protein, and RNA analyses. TBI increased congestion and mucosa erosion and hemorrhage, which were modulated by captopril. GPX-4 and SLC7A11 were downregulated post-irradiation, consistent with ferroptosis at 6 and 35 days post-irradiation in all groups. Interestingly, p21/waf1 increased at 6 days in vehicle-treated but not captopril-treated animals. An RT-qPCR analysis showed that radiation increased the gene expression of inflammatory cytokines IL1B, TNFA, CCL2, IL18, and CXCL8, and the inflammasome component NLRP3. Captopril suppressed radiation-induced IL1B and TNFA. Rectal microbiome analysis showed that 1 day of captopril treatment with radiation decreased overall diversity, with increased Proteobacteria phyla and Escherichia genera. By 6 days, captopril increased the relative abundance of Enterococcus, previously associated with improved H-ARS survival in mice. Our data suggest that captopril mitigates senescence, some inflammation, and microbiome alterations, but not ferroptosis markers in the intestine following TBI.

Underlying Mechanisms behind the Brain-Gut-Liver Axis and Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Metabolic-associated fatty liver disease (MAFLD) includes several metabolic dysfunctions caused by dysregulation in the brain-gut-liver axis and, consequently, increases cardiovascular risks and fatty liver dysfunction. In MAFLD, type 2 diabetes mellitus, obesity, and metabolic syndrome are frequently present; these conditions are related to liver lipogenesis and systemic inflammation. This study aimed to review the connection between the brain-gut-liver axis and MAFLD. The inflammatory process, cellular alterations in hepatocytes and stellate cells, hypercaloric diet, and sedentarism aggravate the prognosis of patients with MAFLD. Thus, to understand the modulation of the physiopathology of MAFLD, it is necessary to include the organokines involved in this process (adipokines, myokines, osteokines, and hepatokines) and their clinical relevance to project future perspectives of this condition and bring to light new possibilities in therapeutic approaches. Adipokines are responsible for the activation of distinct cellular signaling in different tissues, such as insulin and pro-inflammatory cytokines, which is important for balancing substances to avoid MAFLD and its progression. Myokines improve the quantity and quality of adipose tissues, contributing to avoiding the development of MAFLD. Finally, hepatokines are decisive in improving or not improving the progression of this disease through the regulation of pro-inflammatory and anti-inflammatory organokines.

ERCC4: a potential regulatory factor in inflammatory bowel disease and inflammation-associated colorectal cancer

The pathogenesis of inflammatory bowel disease (IBD) remains unclear and is associated with an increased risk of developing colitis-associated cancer (CAC). Under sustained inflammatory stimulation in the intestines, loss of early DNA damage response genes can lead to tumor formation. Many proteins are involved in the pathways of DNA damage response and play critical roles in protecting genes from various potential damages that DNA may undergo. ERCC4 is a structure-specific endonuclease that participates in the nucleotide excision repair (NER) pathway. The catalytic site of ERCC4 determines the activity of NER and is an indispensable gene in the NER pathway. ERCC4 may be involved in the imbalanced process of DNA damage and repair in IBD-related inflammation and CAC. This article primarily reviews the function of ERCC4 in the DNA repair pathway and discusses its potential role in the processes of IBD-related inflammation and carcinogenesis. Finally, we explore how this knowledge may open novel avenues for the treatment of IBD and IBD-related cancer.

Ferroptosis: Biology and Role in Gastrointestinal Disease

Ferroptosis is a form of nonapoptotic cell death that involves iron-dependent phospholipid peroxidation induced by accumulation of reactive oxygen species, and results in plasma membrane damage and the release of damage-associated molecular patterns. Ferroptosis has been implicated in aging and immunity, as well as disease states including intestinal and liver conditions and cancer. To date, several ferroptosis-associated genes and pathways have been implicated in liver disease. Although ferroptotic cell death is associated with dysfunction of the intestinal epithelium, the underlying molecular basis is poorly understood. As the mechanisms regulating ferroptosis become further elucidated, there is clear potential to use ferroptosis to achieve therapeutic benefit.

Iron toxicity, ferroptosis and microbiota in Parkinson's disease: Implications for novel targets

Parkinson's Disease (PD) is a progressive neurodegenerative disease characterized by loss of dopaminergic neurons in substantia nigra pars compacta (SNpc). Iron (Fe)-dependent programmed cell death known as ferroptosis, plays a crucial role in the etiology and progression of PD. Since SNpc is particularly vulnerable to Fe toxicity, a central role for ferroptosis in the etiology and progression of PD is envisioned. Ferroptosis, characterized by reactive oxygen species (ROS)-dependent accumulation of lipid peroxides, is tightly regulated by a variety of intracellular metabolic processes. Moreover, the recently characterized bi-directional interactions between ferroptosis and the gut microbiota, not only provides another window into the mechanistic underpinnings of PD but could also suggest novel interventions in this devastating disease. Here, following a brief discussion of PD, we focus on how our expanding knowledge of Fe-induced ferroptosis and its interaction with the gut microbiota may contribute to the pathophysiology of PD and how this knowledge may be exploited to provide novel interventions in PD.

The Contribution of the Intestinal Microbiota to the Celiac Disease Pathogenesis along with the Effectiveness of Probiotic Therapy

The development of many human disorders, including celiac disease (CD), is thought to be influenced by the microbiota of the gastrointestinal tract and its metabolites, according to current research. This study's goal was to provide a concise summary of the information on the contribution of the intestinal microbiota to the CD pathogenesis, which was actively addressed while examining the reported pathogenesis of celiac disease (CD). We assumed that a change in gluten tolerance is formed under the influence of a number of different factors, including genetic predisposition and environmental factors. In related investigations, researchers have paid increasing attention to the study of disturbances in the composition of the intestinal microbiota and its functional activity in CD. A key finding of our review is that the intestinal microbiota has gluten-degrading properties, which, in turn, may have a protective effect on the development of CD. The intestinal microbiota contributes to maintaining the integrity of the intestinal barrier, preventing the formation of a "leaky" intestine. On the contrary, a change in the composition of the microbiota can act as a significant link in the pathogenesis of gluten intolerance and exacerbate the course of the disease. The possibility of modulating the composition of the microbiota by prescribing probiotic preparations is being considered. The effectiveness of the use of probiotics containing Lactobacillus and Bifidobacterium bacteria in experimental and clinical studies as a preventive and therapeutic agent has been documented.