Vitamin B6 Alleviates Lipopolysaccharide-induced Myocardial Injury by Ferroptosis and Apoptosis Regulation

Delivery of exogenous miR-19b by Wharton's Jelly Mesenchymal Stem Cells attenuates transplanted kidney ischemia/reperfusion injury by regulating cellular metabolism

Renal ischemia-reperfusion injury (IRI) frequently occurs following kidney transplantation, and exosomes derived from umbilical cord mesenchymal stem cells (WJ-MSC-Exos) have shown promise in treating IRI in transplanted kidneys. Our study delved into the potential mechanism of WJ-MSC-Exos in ameliorating IRI in transplanted kidneys, revealing that miR-19b is abundantly present in WJ-MSC-Exos. Both in vivo and in vitro experiments demonstrated that the absence of miR-19b abolished the protective effects of WJ-MSC-Exos against renal IRI. Mechanistically, miR-19b suppressed glycogen synthase kinase-3β (GSK3β) expression, thereby stabilizing PDXK protein through direct binding. Treatment with WJ-MSC-Exos led to reduced PDXK levels and enhanced pyridoxine accumulation, ultimately mitigating IRI in transplanted kidneys and I/R-induced HK2 cell apoptosis. These findings elucidate the underlying mechanism of WJ-MSC-Exos in alleviating IRI in transplanted kidneys, unveiling novel therapeutic targets for post-kidney transplantation IRI and providing a solid theoretical foundation for the clinical application of WJ-MSC-Exos in IRI treatment post-transplantation.

Vitamin B6 alleviates osteoarthritis by suppressing inflammation and apoptosis

BACKGROUND

Although various anti-inflammatory medicines are widely recommended for osteoarthritis (OA) treatment, no significantly clinical effect has been observed. This study aims to examine the effects of vitamin B6, a component that has been reported to be capable of alleviating inflammation and cell death in various diseases, on cartilage degeneration in OA.

METHODS

Collagen-induced arthritis (CIA) mice model were established and the severity of OA in cartilage was determined using the Osteoarthritis Research Society International (OARSI) scoring system. The mRNA and protein levels of indicators associated with extracellular matrix (ECM) metabolism, apoptosis and inflammation were detected. The effect of vitamin B6 (VB6) on the mice were assessed using HE staining and masson staining. The apoptosis rate of cells was assessed using TdT-mediated dUTP nick end labeling.

RESULTS

Our results showed a trend of improved OARSI score in mice treated with VB6, which remarkably inhibited the hyaline cartilage thickness, chondrocyte disordering, and knees hypertrophy. Moreover, the VB6 supplementation reduced the protein expression of pro-apoptosis indicators, including Bax and cleaved caspase-3 and raised the expression level of anti-apoptosis marker Bcl-2. Importantly, VB6 improved ECM metabolism in both in vivo and in vitro experiments.

CONCLUSIONS

This study demonstrated that VB6 alleviates OA through regulating ECM metabolism, inflammation and apoptosis in chondrocytes and CIA mice. The findings in this study provide a theoretical basis for targeted therapy of OA, and further lay the theoretical foundation for studies of mechanisms of VB6 in treating OA.

Vitamin B6 alleviates chronic sleep deprivation-induced hippocampal ferroptosis through CBS/GSH/GPX4 pathway

Several studies have found that sleep deprivation (SD) can lead to neuronal ferroptosis and affect hippocampal function. However, there are currently no effective interventions. Vitamin B6 is a co-factor for key enzymes in the transsulfuration pathway which is critical for maintaining cell growth in the presence of cysteine deprivation. The results showed that SD inhibited cystine-glutamate antiporter light chain subunit xCT protein expression and caused cysteine deficiency, which reduced the synthesis of the glutathione (GSH) to trigger neuronal ferroptosis. Nissl staining further revealed significant neuronal loss and shrinkage in the CA1 and CA3 regions of the hippocampus in SD mice. Typical ferroptotic indicators characterized by lipid peroxidation and iron accumulation were showed in the hippocampus after sleep deprivation. As expected, vitamin B6 could alleviate hippocampal ferroptosis by upregulating the expression of cystathionine beta-synthase (CBS) in the transsulfuration pathway, thereby replenishing the intracellular deficient GSH and restoring the expression of GPX4. Similar anti-ferroptotic effects of vitamin B6 were demonstrated in HT-22 cells treated with ferroptosis activator erastin. Furthermore, vitamin B6 had no inhibitory effect on erastin-induced ferroptosis in CBS-knockout HT22 cells. Our findings suggested chronic sleep deprivation caused hippocampal ferroptosis by disrupting the cyst(e)ine/GSH/GPX4 axis. Vitamin B6 alleviated sleep deprivation-induced ferroptosis by enhancing CBS expression in the transsulfuration pathway.

Current insight on the mechanisms of programmed cell death in sepsis-induced myocardial dysfunction

Sepsis is a clinical syndrome characterized by a dysregulated host response to infection, leading to life-threatening organ dysfunction. It is a high-fatality condition associated with a complex interplay of immune and inflammatory responses that can cause severe harm to vital organs. Sepsis-induced myocardial injury (SIMI), as a severe complication of sepsis, significantly affects the prognosis of septic patients and shortens their survival time. For the sake of better administrating hospitalized patients with sepsis, it is necessary to understand the specific mechanisms of SIMI. To date, multiple studies have shown that programmed cell death (PCD) may play an essential role in myocardial injury in sepsis, offering new strategies and insights for the therapeutic aspects of SIMI. This review aims to elucidate the role of cardiomyocyte's programmed death in the pathophysiological mechanisms of SIMI, with a particular focus on the classical pathways, key molecules, and signaling transduction of PCD. It will explore the role of the cross-interaction between different patterns of PCD in SIMI, providing a new theoretical basis for multi-target treatments for SIMI.

Targeting mitochondrial dynamics proteins for the treatment of doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an extensively used chemotherapeutic agent that can cause severe and frequent cardiotoxicity, which limits its clinical application. Although there have been extensive researches on the cardiotoxicity caused by DOX, there is still a lack of effective treatment. It is necessary to understand the molecular mechanism of DOX-induced cardiotoxicity and search for new therapeutic targets which do not sacrifice their anticancer effects. Mitochondria are considered to be the main target of cardiotoxicity caused by DOX. The imbalance of mitochondrial dynamics characterized by increased mitochondrial fission and inhibited mitochondrial fusion is often reported in DOX-induced cardiotoxicity, which can result in excessive ROS production, energy metabolism disorders, cell apoptosis, and various other problems. Also, mitochondrial dynamics disorder is related to tumorigenesis. Surprisingly, recent studies show that targeting mitochondrial dynamics proteins such as DRP1 and MFN2 can not only defend against DOX-induced cardiotoxicity but also enhance or not impair the anticancer effect. Herein, we summarize mitochondrial dynamics disorder in DOX-induced cardiac injury. Furthermore, we provide an overview of current pharmacological and non-pharmacological interventions targeting proteins involved in mitochondrial dynamics to alleviate cardiac damage caused by DOX.

Pharmacological inhibition of ferroptosis as a therapeutic target for sepsis-associated organ damage

Sepsis is a complex clinical syndrome caused by dysfunctional host response to infection, which contributes to excess mortality and morbidity worldwide. The development of life-threatening sepsis-associated organ injury to the brain, heart, kidneys, lungs, and liver is a major concern for sepsis patients. However, the molecular mechanisms underlying sepsis-associated organ injury remain incompletely understood. Ferroptosis, an iron-dependent non-apoptotic form of cell death characterized by lipid peroxidation, is involved in sepsis and sepsis-related organ damage, including sepsis-associated encephalopathy, septic cardiomyopathy, sepsis-associated acute kidney injury, sepsis-associated acute lung injury, and sepsis-induced acute liver injury. Moreover, compounds that inhibit ferroptosis exert potential therapeutic effects in the context of sepsis-related organ damage. This review summarizes the mechanism by which ferroptosis contributes to sepsis and sepsis-related organ damage. We focus on the emerging types of therapeutic compounds that can inhibit ferroptosis and delineate their beneficial pharmacological effects for the treatment of sepsis-related organ damage. The present review highlights pharmacologically inhibiting ferroptosis as an attractive therapeutic strategy for sepsis-related organ damage.

Targeting ferroptosis as a promising therapeutic strategy to treat cardiomyopathy

Cardiomyopathies are a clinically heterogeneous group of cardiac diseases characterized by heart muscle damage, resulting in myocardium disorders, diminished cardiac function, heart failure, and even sudden cardiac death. The molecular mechanisms underlying the damage to cardiomyocytes remain unclear. Emerging studies have demonstrated that ferroptosis, an iron-dependent non-apoptotic regulated form of cell death characterized by iron dyshomeostasis and lipid peroxidation, contributes to the development of ischemic cardiomyopathy, diabetic cardiomyopathy, doxorubicin-induced cardiomyopathy, and septic cardiomyopathy. Numerous compounds have exerted potential therapeutic effects on cardiomyopathies by inhibiting ferroptosis. In this review, we summarize the core mechanism by which ferroptosis leads to the development of these cardiomyopathies. We emphasize the emerging types of therapeutic compounds that can inhibit ferroptosis and delineate their beneficial effects in treating cardiomyopathies. This review suggests that inhibiting ferroptosis pharmacologically may be a potential therapeutic strategy for cardiomyopathy treatment.

Platelet-rich plasma ameliorates lipopolysaccharide-induced cardiac injury by inflammation and ferroptosis regulation

Sepsis-induced myocardial dysfunction (SIMD) is a fatal disease with no specific treatment worldwide to this day. As a biological product, platelet-rich plasma (PRP) has attracted much attention due to its diverse and potential biological effects. However, its role in lipopolysaccharide (LPS)-induced cardiac injury has not been fully investigated. This study aimed to explore the mechanism of PRP in SIMD. PRP (30 µL) was injected in situ into the heart, and LPS (10 mg/kg) was injected intraperitoneally into mice. Neonatal rat cardiomyocytes were treated with LPS (1 μg/ml) for 24 h. The results showed that, compared with the LPS group, PRP significantly decreased the levels of Lactate dehydrogenase (LDH) and Creatine Kinase MB (CK-MB), and improved cardiac function. In addition, PRP markedly decreased the Malonic dialdehyde (MDA) content, and increased the Superoxide dismutase (SOD) activity and Glutathione (GSH) level, demonstrating that PRP alleviated LPS-induced oxidative stress. The Western blot and qPCR results showed that LPS-induced ferroptosis and inflammation effects in vivo and in vitro were ameliorated after PRP treatment. Moreover, PRP can alleviate erastin-induced ferroptosis and improve cell viability. Mechanistically, p-AKT and p-mTOR expressions were down-regulated after treatment with LPS, while PRP pretreatment could reverse this effect. In summary, our study demonstrated that PRP could play a unique role in reducing LPS-induced cardiac injury through regulation of AKT/mTOR signaling pathways. These findings provide a new therapeutic direction for treating SIMD.

Crosstalk between regulated necrosis and micronutrition, bridged by reactive oxygen species

The discovery of regulated necrosis revitalizes the understanding of necrosis from a passive and accidental cell death to a highly coordinated and genetically regulated cell death routine. Since the emergence of RIPK1 (receptor-interacting protein kinase 1)-RIPK3-MLKL (mixed lineage kinase domain-like) axis-mediated necroptosis, various other forms of regulated necrosis, including ferroptosis and pyroptosis, have been described, which enrich the understanding of pathophysiological nature of diseases and provide novel therapeutics. Micronutrients, vitamins, and minerals, position centrally in metabolism, which are required to maintain cellular homeostasis and functions. A steady supply of micronutrients benefits health, whereas either deficiency or excessive amounts of micronutrients are considered harmful and clinically associated with certain diseases, such as cardiovascular disease and neurodegenerative disease. Recent advance reveals that micronutrients are actively involved in the signaling pathways of regulated necrosis. For example, iron-mediated oxidative stress leads to lipid peroxidation, which triggers ferroptotic cell death in cancer cells. In this review, we illustrate the crosstalk between micronutrients and regulated necrosis, and unravel the important roles of micronutrients in the process of regulated necrosis. Meanwhile, we analyze the perspective mechanism of each micronutrient in regulated necrosis, with a particular focus on reactive oxygen species (ROS).