The Ferroptosis-NLRP1 Inflammasome: The Vicious Cycle of an Adverse Pregnancy

SIRT5 safeguards against T-2 toxin induced liver injury by repressing iron accumulation, oxidative stress, and the activation of NLRP3 inflammasome

T-2 toxin, a highly toxic trichothecene mycotoxin widely found in food and feed, poses a significant threat to human health as well as livestock and poultry industry. Liver, being a crucial metabolic organ, is particularly susceptible to T-2 toxin induced damage characterized by inflammation and oxidative stress. Despite the role of Sirtuin 5 (SIRT5) in mitigating liver injury has been confirmed, its specific impact on T-2 toxin induced liver injury remains to be elucidated. The objective of this study was to investigate the protective role of SIRT5 against T-2 toxin induced liver injury in mice. Following the oral administration of 1 mg/kg.bw of T-2 toxin for 21 consecutive days to SIRT5 knockout (SIRT5-/-) and wild-type (WT) male mice, liver assessments were conducted. Our findings demonstrated that aggravated hepatic pathological injury was observed in SIRT5-/- mice, accompanied by elevated malondialdehyde (MDA) and Fe levels, as well as enhanced expression of glutathione peroxidase 4 (GPX4), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, Gasdermin-D (GSDMD), tumour necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β). These results indicated that SIRT5 alleviated hepatic structural damage and dysfunction, while inhibiting oxidative stress, iron accumulation, and NLRP3 inflammasome activation. Analysis revealed a positive correlation among NLRP3 inflammasome activation, iron accumulation, and oxidative stress. Overall, our study demonstrated that SIRT5 mitigated liver injury induced by T-2 toxin through inhibiting iron accumulation, oxidative stress, and NLRP3 inflammasome activation, providing novel insights into the management and prevention of T-2 toxin poisoning.

Inflammasome activity regulation by PUFA metabolites

Oxidative stress and the accompanying chronic inflammation constitute an important metabolic problem that may lead to pathology, especially when the body is exposed to physicochemical and biological factors, including UV radiation, pathogens, drugs, as well as endogenous metabolic disorders. The cellular response is associated, among others, with changes in lipid metabolism, mainly due to the oxidation and the action of lipolytic enzymes. Products of oxidative fragmentation/cyclization of polyunsaturated fatty acids (PUFAs) [4-HNE, MDA, 8-isoprostanes, neuroprostanes] and eicosanoids generated as a result of the enzymatic metabolism of PUFAs significantly modify cellular metabolism, including inflammation and the functioning of the immune system by interfering with intracellular molecular signaling. The key regulators of inflammation, the effectiveness of which can be regulated by interacting with the products of lipid metabolism under oxidative stress, are inflammasome complexes. An example is both negative or positive regulation of NLRP3 inflammasome activity by 4-HNE depending on the severity of oxidative stress. 4-HNE modifies NLRP3 activity by both direct interaction with NLRP3 and alteration of NF-κB signaling. Furthermore, prostaglandin E2 is known to be positively correlated with both NLRP3 and NLRC4 activity, while its potential interference with AIM2 or NLRP1 activity is unproven. Therefore, the influence of PUFA metabolites on the activity of well-characterized inflammasome complexes is reviewed.

Proteomics Analysis of Human Chorionic Villi Reveals Dysregulated Pathways That Contribute to Recurrent Pregnancy Loss

PURPOSE

Recurrent pregnancy loss (RPL) represents a common disorder with consequences on family and society. As more than half of the RPL cases do not have a clearly identified cause, uncovering the mechanisms behind the idiopathic RPL is urgently needed.

EXPERIMENTAL DESIGN

Using label-free data-independent LC-MS/MS acquisition coupled with ion mobility, we compared the proteome of chorionic villi from 13 RPL cases with 10 age and gestational week-matched elective pregnancies. Transcriptional levels of selected candidate biomarkers were determined in chorionic villi of 35 RPL cases and 25 controls using quantitative polymerase chain reaction (qPCR).

RESULTS

Statistically significant difference in abundance (Benjamini-Hochberg [B-H] p ≤ 0.05) and fold change ≥1.5 showed 128 proteins. Bioinformatics analysis identified complement and coagulation cascades, platelet activation, tricarboxylic acid cycle (TCA) cycle, and ferroptosis as pathways with the highest significance. Correlation with transcriptome datasets revealed a weak statistically significant positive correlation with 45% of the co-differentially expressed proteins/genes displaying the same regulation trend. The transcription levels of neurofilament light polypeptide (NEFL), dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex_mitochondrial (DLST), nitric oxide synthase 3 (NOS3), and ceruloplasmin (CP) were significantly increased in the RPL, consistent with the proteomics findings.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data suggests alteration of several pathways as potential causes of idiopathic RPL from the fetal side and opens the way for investigations concerning clinical management.

Puerarin inhibits Staphylococcus aureus-induced endometritis through attenuating inflammation and ferroptosis via regulating the P2X7/NLRP3 signalling pathway

Endometritis is one of the important causes of infertility. Puerarin (PU) can inhibit oxidative stress and reduce inflammation; however, it is unclear whether PU has a protective effect on the endometritis. In our study, we used Staphylococcus aureus to induce mouse endometritis. The PU group (100 mg/kg PU) and the S. aureus + PU group received daily intraperitoneal injection of PU (25, 50 or 100 mg/kg PU). The results showed that S. aureus significantly increased the levels of MPO, TNF-α, IL-1β and IL-6 in uterine tissue, and increased the expression of p-p65 and p-IκBα proteins in uterine tissue to induce endometritis in mice (p < 0.05). Furthermore, it has been found that S. aureus promotes the occurrence of ferroptosis by reducing GSH and ATP content, increasing MDA and iron content and reducing GPX4 and SLC7A11 protein expression levels (p < 0.05). S. aureus significantly increase the expression of NLRP3, ASC, caspase-1 and P2X7 proteins in uterine tissue (p < 0.05). However, PU obviously reduced the inflammatory response and reversed the changes of ferroptosis and the expression of P2X7 receptor/NLRP3 pathway associated proteins of the uterus induced by S. aureus (p < 0.05). Taken together, these findings emphasize the protective effect of PU on endometritis by regulating the P2X7 receptor/NLRP3 signalling pathway and inhibiting ferroptosis.

Cryptochrome 2 Suppresses Epithelial-Mesenchymal Transition by Promoting Trophoblastic Ferroptosis in Unexplained Recurrent Spontaneous Abortion

Unexplained recurrent spontaneous abortion (URSA) is a serious reproductive issue that affects women of childbearing age. Studies have shown a close association between disrupted circadian rhythm and impaired epithelial-mesenchymal transition (EMT) in trophoblasts during URSA, although the underlying mechanism is not known. The current study investigated the regulatory relationship between circadian rhythm gene cryptochrome 2 (CRY2) and ferroptosis on the migratory ability of trophoblast cells. Cell proliferation experiments, wound-healing assays, and expression of related markers were conducted to study EMT. Trophoblastic ferroptosis was confirmed by the expressions of malondialdehyde, glutathione, mitochondrial membrane potential, divalent iron ions, and related genes. The results showed significant increased expression of CRY2 and decreased expression of brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) in the URSA villous tissues, accompanied by iron-dependent oxidative changes and abnormal expression of ferroptosis-related proteins. CRY2 and BMAL1 were co-localized and functioned as a feedback loop, which regulated the dynamic changes of EMT-related markers in trophoblast cells. CRY2 promoted trophoblastic ferroptosis, whereas BMAL1 had the opposite effect. Particularly, the ferroptosis inhibitor (ferrostatin-1) effectively reversed the trophoblastic ferroptosis and EMT inhibition caused by CRY2 overexpression. Collectively, these results suggest that CRY2 regulates trophoblastic ferroptosis and hinders cellular EMT and migratory ability by suppressing BMAL1 expression.

Effects of early pregnancy on NOD-like receptor expression in the ovine endometrium

Introduction

Nucleotide-binding domain (NOD)-like receptors (NLRs) are expressed in the endometrium, and involved in modulating the female innate immune responses. There are conceptus-endometrial interactions during pregnancy, which ensure immune homeostasis of the maternal-fetal interface. The purpose of this study was to explore the effects of early pregnancy on NLR expression in the ovine endometrium.

Methods

Endometrial tissues were collected at day 16 of the estrous cycle, and at days 13, 16 and 25 of pregnancy (n = 6 for each group), and RT-qPCR, western blot and immunohistochemistry analysis were used to analyze the expression of NLRs, including NOD1, NOD2, major histocompatibility complex class II transactivator (CIITA), neuronal apoptosis inhibitor protein (NAIP), NLR family, pyrin domain-containing 1 (NLRP1), NLRP3 and NLRP7.

Results

Expression levels of NOD1, NOD2, NAIP, CIITA, NLRP1 and NLRP3 declined, but expression level of NLRP7 increased in the endometria during early pregnancy compared with nonpregnant ewes. In addition, NOD2 and CIITA proteins were located in the endometrium in a protein type-, cell type- and pregnancy status-specific manner.

Discussion

Early pregnancy modulated expression of NLR family in the ovine endometrium, which may be essential for conceptus-endometrial interactions and maternal-fetal interface immune homeostasis.

A preliminary study unveils CISD2 as a ferroptosis-related therapeutic target for recurrent spontaneous abortion through immunological analysis and two-sample mendelian randomization

Recurrent spontaneous abortion (RSA) affects approximately 1 % of women striving for conception, posing a significant clinical challenge. This study aimed to identify a prognostic signature in RSA and elucidate its molecular mechanisms. Prognostic gene impacts were further assessed in HTR-8/SVneo and human primary extravillous trophoblast (EVT) cells in vitro experiments. A total of 6168 differentially expressed genes (DEGs) were identified, including 3035 upregulated and 3133 downregulated genes. WGCNA pinpointed 8 significant modules and 31 ferroptosis-related DEGs in RSA. Optimal clustering classified RSA patients into three distinct subgroups, showing notable differences in immune cell composition. Six feature genes (AEBP2, CISD2, PML, RGS4, SRSF9, STK11) were identified. The diagnostic model showed high predictive capabilities (AUC: 0.966). Mendelian randomization indicated a significant association between CISD2 levels and RSA (OR: 1.069, P-value: 0.049). Furthermore, the downregulation of CISD2 promotes ferroptosis in HTR-8/SVneo and human primary EVT cells. CISD2 emerged as a pivotal gene in RSA, serving as a ferroptosis-related therapeutic target. The diagnostic model based on gene expression and Mendelian randomization provides novel insights into the pathogenesis of RSA.

Research trends of ferroptosis and pyroptosis in Parkinson's disease: a bibliometric analysis

Objective

This study aims to visualize the trends and hotspots in the research of "ferroptosis in PD" and "pyroptosis in PD" through bibliometric analysis from the past to 2024.

Methods

Literature was retrieved from the Web of Science Core Collection (WoSCC) from the past to February 16, 2024, and bibliometric analysis was conducted using Vosviewer and Citespace.

Results

283 and 542 papers were collected in the field of "ferroptosis in PD" and "pyroptosis in PD." The number of publications in both fields has increased yearly, especially in "ferroptosis in PD," which will become the focus of PD research. China, the United States and England had extensive exchanges and collaborations in both fields, and more than 60% of the top 10 institutions were from China. In the fields of "ferroptosis in PD" and "pyroptosis in PD," the University of Melbourne and Nanjing Medical University stood out in terms of publication numbers, citation frequency, and centrality, and the most influential journals were Cell and Nature, respectively. The keyword time zone map showed that molecular mechanisms and neurons were the research hotspots of "ferroptosis in PD" in 2023, while memory and receptor 2 were the research hotspots of "pyroptosis in PD" in 2023, which may predict the future research direction.

Conclusion

This study provides insights into the development, collaborations, research themes, hotspots, and tendencies of "ferroptosis in PD" and "pyroptosis in PD." Overall situation of these fields is available for researchers to further explore the underlying mechanisms and potential treatments.

NLRP inflammasomes in health and disease

NLRP inflammasomes are a group of cytosolic multiprotein oligomer pattern recognition receptors (PRRs) involved in the recognition of pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) produced by infected cells. They regulate innate immunity by triggering a protective inflammatory response. However, despite their protective role, aberrant NLPR inflammasome activation and gain-of-function mutations in NLRP sensor proteins are involved in occurrence and enhancement of non-communicating autoimmune, auto-inflammatory, and neurodegenerative diseases. In the last few years, significant advances have been achieved in the understanding of the NLRP inflammasome physiological functions and their molecular mechanisms of activation, as well as therapeutics that target NLRP inflammasome activity in inflammatory diseases. Here, we provide the latest research progress on NLRP inflammasomes, including NLRP1, CARD8, NLRP3, NLRP6, NLRP7, NLRP2, NLRP9, NLRP10, and NLRP12 regarding their structural and assembling features, signaling transduction and molecular activation mechanisms. Importantly, we highlight the mechanisms associated with NLRP inflammasome dysregulation involved in numerous human auto-inflammatory, autoimmune, and neurodegenerative diseases. Overall, we summarize the latest discoveries in NLRP biology, their forming inflammasomes, and their role in health and diseases, and provide therapeutic strategies and perspectives for future studies about NLRP inflammasomes.

Excessive fluoride induces ovarian function impairment by regulating levels of ferroptosis in fluorosis women and ovarian granulosa cells

The aim of this study was to investigate the role of ferroptosis in fluorosis women and the in vitro molecular mechanisms leading to ovarian dysfunction and abnormal hormone secretion by sodium fluoride (NaF) treatment of KGN cells. Fifty women with fluorosis as Fluorosis group and fifty healthy women as Control group were included in this study. The levels of lipid peroxidation and activities of antioxidant enzyme were assessed by photometric methods. The content of iron and glutathione (GSH) in serum was measured by microplate method. KGN cells were treated by different concentration of NaF (0, 1, 2, 4 and 8 ×10-3 M) for 24 h. The mRNA and protein expression levels of ferroptosis-related molecules, including glutathione peroxidase 4 (GPX4), solute carrier family 7 member (SLC7A11), nuclear factor erythroid 2-related factor 2 (Nrf2), ferritin heavy chain 1 (FTH1) and p53, were assessed by qRT-PCR and western blot analysis. Fluorosis group women had a significant higher levels of iron, Malondialdehyde (MDA), FSH and LH, and a lower levels of E2 and antioxidant enzyme in serum than that in the control group. The representative molecular changes of ferroptosis, such as the decrease in GPX4, Nrf2 and SLC7A11 expression (mRNA and protein expression), the increase in protein expression of p53, and a reduced level of E2 were observed in KGN cells treated by excessive NaF.It is concluded therefore that NaF increases the expression of p53 and inhibits ovarian granulosa cell ferroptosis preventive protein expression, resulting in abnormal hormone secretion and the ovarian dysfunction.

FRP-XGBoost: Identification of ferroptosis-related proteins based on multi-view features

Ferroptosis represents a novel form of programmed cell death. Pan-cancer bioinformatics analysis indicates that identifying and modulating ferroptosis offer innovative approaches for preventing and treating diverse tumor pathologies. However, the precise detection of ferroptosis-related proteins via conventional wet-laboratory techniques remains a formidable challenge, largely due to the constraints of existing methodologies. These traditional approaches are not only labor-intensive but also financially burdensome. Consequently, there is an imperative need for the development of more sophisticated and efficient computational tools to facilitate the detection of these proteins. In this paper, we presented a XGBoost and multi-view features-based machine learning prediction method for predicting ferroptosis-related proteins, which was referred to as FRP-XGBoost. In this study, we explored four types of protein feature extraction methods and evaluated their effectiveness in predicting ferroptosis-related proteins using six of the most commonly used traditional classifiers. To enhance the representational power of the hybrid features, we employed a two-step feature selection technique to identify the optimal subset of features. Subsequently, we constructed a prediction model using the XGBoost algorithm. The FRP-XGBoost achieved an accuracy of 96.74 % in 10-fold cross-validation and a further accuracy of 91.52 % in an independent test. The implementation source code of FRP-XGBoost is available at https://github.com/linli5417/FRP-XGBoost.

NLRP3 inflammasome pathway, the hidden balance in pregnancy: A comprehensive review

The balance of the inflammatory response is indispensable during pregnancy. Inflammasomes are the cytosolic supramolecular protein complexes activated by pattern recognition receptors. These receptors recognize the pathogen and damage/danger-associated molecular patterns. NLRP3 inflammasome complex consists mainly of NLRP3 (leucine-rich repeat-containing and pyrin domain-containing protein 3), a cytosolic sensor molecule, ASC (apoptosis-associated speck-like protein containing a CARD) protein and a cysteine protease pro-caspase-1 as an effector molecule. This complex has a role in producing inflammatory cytokines, interleukin 1 beta and interleukin 18, and inflammasome-dependent programmed cell death pathway pyroptosis. In this review, we focused on and summarised the NLRP3 inflammasome and its roles in normal and pathological pregnancies. The NLRP3 inflammasome pathway influences endometrial receptivity and embryo invasion by inducing epithelial-mesenchymal transition. Abnormal inflammasome activation in the endometrium may adversely affect endometrial receptivity. In addition, NLRP3 inflammasome pathway overactivation may mediate the abnormal inflammatory response at the maternal-fetal interface and be associated with pregnancy complications, such as recurrent implantation failure, pregnancy loss, pre-term birth and pre-eclampsia. Therefore, targeting the NLRP3 inflammasome pathway could develop a new therapeutic approach to prevent the aforementioned pregnancy pathologies.

Modified Shoutai Pill inhibited ferroptosis to alleviate recurrent pregnancy loss

ETHNOPHARMACOLOGICAL RELEVANCE

Modified Shoutai Pill, also called Jianwei Shoutai Pill (JSP), is a traditional Chinese medicine prescription that has been used as an effective agent for the treatment of miscarriage.

AIM OF THE STUDY

To explore the potential molecular mechanism of JSP against recurrent pregnancy loss (RPL).

MATERIALS AND METHODS

In vivo, CBA/J mated DBA/2 mice were used to conduct RPL model, while CBA/J mated BALB/c mice were seen as the control group. Mice were orally administered with JSP, Fer-1 (a ferroptosis inhibitor) or distilled water from day 0.5-12.5 of gestation (GD 0.5-12.5). Pregnancy outcomes were analyzed and ferroptosis related indexes of the whole implantation sites were measured on GD 12.5. In vitro, human trophoblast cell line HTR-8/SVneo was cultured and treated with RAS-selective lethal small molecule 3 (RSL3) (a ferroptosis agonist) or different concentrations of JSP. Then, ferroptosis related indexes were tested to analyze whether JSP could inhibit ferroptosis in HTR-8/SVneo cells.

RESULTS

In vivo consequences demonstrated that JSP or Fer-1 alleviated pregnancy outcomes including lower resorption rate and abortion rate. In addition, excessive iron accumulation and MDA level were inhibited, while GSH and GPX content were raised under JSP or Fer-1 exposure. Also, JSP or Fer-1 enhanced protein expressions of GPX4 and SLC7A11 which suppress ferroptosis, and lightened protein expression of ACSL4 which boosts ferroptosis. In vitro, JSP rescued HTR-8/SVneo cell death and migration ability that were injured by RSL3. Furthermore, JSP inhibited RSL3-induced intracellular reactive oxygen species (ROS), lipid ROS and iron deposition.

CONCLUSIONS

Collectively, our findings illustrated that the mechanism of JSP in treating RPL might be related to inhibiting ferroptosis, which provided a novel insight into the application of JSP in RPL intervention.

The Role of Histone Deacetylases in NLRP3 Inflammasomesmediated Epilepsy

Epilepsy is one of the most common brain disorders that not only causes death worldwide, but also affects the daily lives of patients. Previous studies have revealed that inflammation plays an important role in the pathophysiology of epilepsy. Activation of inflammasomes can promote neuroinflammation by boosting the maturation of caspase-1 and the secretion of various inflammatory effectors, including chemokines, interleukins, and tumor necrosis factors. With the in-depth research on the mechanism of inflammasomes in the development of epilepsy, it has been discovered that NLRP3 inflammasomes may induce epilepsy by mediating neuronal inflammatory injury, neuronal loss and blood-brain barrier dysfunction. Therefore, blocking the activation of the NLRP3 inflammasomes may be a new epilepsy treatment strategy. However, the drugs that specifically block NLRP3 inflammasomes assembly has not been approved for clinical use. In this review, the mechanism of how HDACs, an inflammatory regulator, regulates the activation of NLRP3 inflammasome is summarized. It helps to explore the mechanism of the HDAC inhibitors inhibiting brain inflammatory damage so as to provide a potential therapeutic strategy for controlling the development of epilepsy.

An investigation of the distributions of ferroptosis and necroptosis mediators in the maternal-fetal interface at different days of rat pregnancy

Ferroptosis and necroptosis are recognized as playing major roles in the regulation of various physiological processes. However, the physiological role of the cell death mediated by these two pathways in the developmental process has not yet been clearly established. This study investigated ferroptosis and necroptosis signalling pathways in maternal-fetal tissue in the different gestational days (GD) of rat pregnancy using immunohistochemical and western blot methods in order to fill this gap. Twenty-four female Wistar albino rats were mated and divided into three groups. Maternal-fetal tissue samples were collected on GD 5, 12 and 19 of pregnancy. Expression and total protein levels of the markers glutathione peroxidase-4, soluble transporter family 7 member 11, transferrin receptor, receptor-interacting serine/threonine-protein kinase 1, receptor-interacting serine/threonine-protein kinase 3 and mixed lineage kinase domain-like protein were investigated on both the maternal and fetal surfaces of the placenta using immunohistochemical and western blot methods. The results showed varying levels of protein expression of both ferroptosis and necroptosis mediators in the GD 5, 12 and 19 of pregnancy. Immunohistochemical analyses revealed that these mediators were located on both the maternal (decidua and metrial gland) and fetal surfaces (labyrinth zone, yolk sac and basal zone) and that their expression levels changed in the different GD. The findings revealed the existence of important ferroptosis and necroptosis pathway mediators in rat maternal-fetal tissue. These results may provide a molecular framework for a better understanding of the communication between the placenta, decidua and fetus during the developmental process.

Ferroptosis: an important player in the inflammatory response in diabetic nephropathy

Diabetic nephropathy (DN) is a chronic inflammatory disease that affects millions of diabetic patients worldwide. The key to treating of DN is early diagnosis and prevention. Once the patient enters the clinical proteinuria stage, renal damage is difficult to reverse. Therefore, developing early treatment methods is critical. DN pathogenesis results from various factors, among which the immune response and inflammation play major roles. Ferroptosis is a newly discovered type of programmed cell death characterized by iron-dependent lipid peroxidation and excessive ROS production. Recent studies have demonstrated that inflammation activation is closely related to the occurrence and development of ferroptosis. Moreover, hyperglycemia induces iron overload, lipid peroxidation, oxidative stress, inflammation, and renal fibrosis, all of which are related to DN pathogenesis, indicating that ferroptosis plays a key role in the development of DN. Therefore, this review focuses on the regulatory mechanisms of ferroptosis, and the mutual regulatory processes involved in the occurrence and development of DN and inflammation. By discussing and analyzing the relationship between ferroptosis and inflammation in the occurrence and development of DN, we can deepen our understanding of DN pathogenesis and develop new therapeutics targeting ferroptosis or inflammation-related regulatory mechanisms for patients with DN.

Ferroptosis in acute kidney injury following crush syndrome: A novel target for treatment

BACKGROUND

Crush syndrome (CS) is a kind of traumatic and ischemic injury that seriously threatens life after prolonged compression. It is characterized by systemic inflammatory reaction, myoglobinuria, hyperkalemia and acute kidney injury (AKI). Especially AKI, it is the leading cause of death from CS. There are various cell death forms in AKI, among which ferroptosis is a typical form of cell death. However, the role of ferroptosis has not been fully revealed in CS-AKI.

AIM OF REVIEW

This review aimed to summarize the evidence of ferroptosis in CS-AKI and its related molecular mechanism, discuss the therapeutic significance of ferroptosis in CS-AKI, and open up new ideas for the treatment of CS-AKI.

KEY SCIENTIFIC CONCEPTS OF REVIEW

One of the main pathological manifestations of CS-AKI is renal tubular epithelial cell dysfunction and cell death, which has been attributed to massive deposition of myoglobin. Large amounts of myoglobin released from damaged muscle deposited in the renal tubules, impeding the normal renal tubules function and directly damaging the tubules with oxidative stress and elevated iron levels. Lipid peroxidation damage and iron overload are the distinguishing features of ferroptosis. Moreover, high levels of pro-inflammatory cytokines and damage-associated molecule pattern molecules (HMGB1, double-strand DNA, and macrophage extracellular trap) in renal tissue have been shown to promote ferroptosis. However, how ferroptosis occurs in CS-AKI and whether it can be a therapeutic target remains unclear. In our current work, we systematically reviewed the occurrence and underlying mechanism of ferroptosis in CS-AKI.

Next Generation, Modifiable Cardiometabolic Biomarkers: Mitochondrial Adaptation and Metabolic Resilience: A Scientific Statement From the American Heart Association

Cardiometabolic risk is increasing in prevalence across the life span with disproportionate ramifications for youth at socioeconomic disadvantage. Established risk factors and associated disease progression are harder to reverse as they become entrenched over time; if current trends are unchecked, the consequences for individual and societal wellness will become untenable. Interrelated root causes of ectopic adiposity and insulin resistance are understood but identified late in the trajectory of systemic metabolic dysregulation when traditional cardiometabolic risk factors cross current diagnostic thresholds of disease. Thus, children at cardiometabolic risk are often exposed to suboptimal metabolism over years before they present with clinical symptoms, at which point life-long reliance on pharmacotherapy may only mitigate but not reverse the risk. Leading-edge indicators are needed to detect the earliest departure from healthy metabolism, so that targeted, primordial, and primary prevention of cardiometabolic risk is possible. Better understanding of biomarkers that reflect the earliest transitions to dysmetabolism, beginning in utero, ideally biomarkers that are also mechanistic/causal and modifiable, is critically needed. This scientific statement explores emerging biomarkers of cardiometabolic risk across rapidly evolving and interrelated "omic" fields of research (the epigenome, microbiome, metabolome, lipidome, and inflammasome). Connections in each domain to mitochondrial function are identified that may mediate the favorable responses of each of the omic biomarkers featured to a heart-healthy lifestyle, notably to nutritional interventions. Fuller implementation of evidence-based nutrition must address environmental and socioeconomic disparities that can either facilitate or impede response to therapy.

The emerging role of ferroptosis in female reproductive disorders

Iron, as an essential trace element for the organism, is vital for maintaining the organism's health. Excessive iron can promote reactive oxygen species (ROS) accumulation, thus damaging cells and tissues. Ferroptosis is a novel form of programmed cell death distinguished by iron overload and lipid peroxidation, which is unique from autophagy, apoptosis and necrosis, more and more studies are focusing on ferroptosis. Recent evidence suggests that ferroptosis is associated with the development of female reproductive disorders (FRDs), including polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI), endometriosis (EMs), ovarian cancer (OC), preeclampsia (PE) and spontaneous abortion (SA). Pathways and genes associated with ferroptosis may participate in processes that regulate granulosa cell proliferation and secretion, oocyte development, ovarian reserve function, early embryonic development and placental oxidative stress. However, its exact mechanism has not been fully revealed. Therefore, our review systematically elaborates the occurrence mechanism of ferroptosis and its research progress in the development of FRDs, with a view to providing literature references for clinical targeting of ferroptosis -related pathways and regulatory factors for the management of FRDs.

Changes in expression levels of Nod-like receptors in the spleen of ewes

Nucleotide-binding oligomerization domain receptors (NOD-like receptors, NLRs) have critical effects on interfaces of the immune and reproductive systems, and the spleen plays a key role in both innate and adaptive immune functions. It is hypothesized that NLR family participates in maternal splenic immune regulation during early pregnancy in sheep. In this study, maternal spleens were collected on day 16 of the estrous cycle, and days 13, 16 and 25 of gestation (n = 6 for each group) in ewes. Expression of NLR family, including NOD1, NOD2, class II transactivator (CIITA), NLR family apoptosis inhibitory protein (NAIP), nucleotide-binding oligomerization domain, Leucine rich repeat and Pyrin domain containing 1 (NLRP1), NLRP3 and NLRP7, was analyzed using quantitative real-time PCR, Western blot and immunohistochemistry analysis. The results revealed that expression levels of NOD1, NOD2, CIITA and NLRP3 were downregulated at days 13 and 16 of pregnancy, but expression of NLRP3 was increased at day 25 of pregnancy. In addition, expression values of NAIP and NLRP7 mRNA and proteins were improved at days 16 and 25 of pregnancy, and NLRP1 was peaked at days 13 and 16 of pregnancy in the maternal spleen. Furthermore, NOD2 and NLRP7 proteins were limited to the capsule, trabeculae and splenic cords. In summary, early pregnancy changes expression of NLR family in the maternal spleen, which may be related with the maternal splenic immunomodulation during early pregnancy in sheep.

Maternal SARS-CoV-2, Placental Changes and Brain Injury in 2 Neonates

Long-term neurodevelopmental sequelae are a potential concern in neonates following in utero exposure to severe acute respiratory syndrome coronavirus disease 2 (SARS-CoV-2). We report 2 neonates born to SARS-CoV-2 positive mothers, who displayed early-onset (day 1) seizures, acquired microcephaly, and significant developmental delay over time. Sequential MRI showed severe parenchymal atrophy and cystic encephalomalacia. At birth, neither infant was SARS-CoV-2 positive (nasopharyngeal swab, reverse transcription polymerase chain reaction), but both had detectable SARS-CoV-2 antibodies and increased blood inflammatory markers. Placentas from both mothers showed SARS-CoV-2-nucleocapsid protein and spike glycoprotein 1 in the syncytiotrophoblast, fetal vascular malperfusion, and significantly increased inflammatory and oxidative stress markers pyrin domain containing 1 protein, macrophage inflammatory protein 1 βη, stromal cell-derived factor 1, interleukin 13, and interleukin 10, whereas human chorionic gonadotropin was markedly decreased. One infant (case 1) experienced sudden unexpected infant death at 13 months of age. The deceased infant's brain showed evidence of SARS-CoV-2 by immunofluorescence, with colocalization of the nucleocapsid protein and spike glycoprotein around the nucleus as well as within the cytoplasm. The constellation of clinical findings, placental pathology, and immunohistochemical changes strongly suggests that second-trimester maternal SARS-CoV-2 infection with placentitis triggered an inflammatory response and oxidative stress injury to the fetoplacental unit that affected the fetal brain. The demonstration of SARS-CoV-2 in the deceased infant's brain also raises the possibility that SARS-CoV-2 infection of the fetal brain directly contributed to ongoing brain injury. In both infants, the neurologic findings at birth mimicked the presentation of hypoxic-ischemic encephalopathy of newborn and neurologic sequelae progressed well beyond the neonatal period.

Regulatory mechanism and research progress of ferroptosis in obstetrical and gynecological diseases

Ferroptosis is a novel type of regulated cell death driven by iron-dependent lipid peroxidation, which is distinguished from traditional types of programmed cell death, such as apoptosis, proptosis and necrosis et al. Impaired iron homeostasis, lipid peroxidation and antioxidants depletion are three hallmarks of ferroptosis. Over the past years, emerging studies support the notion that ferroptosis might be involved in the pathology of obstetrical and gynecological diseases, including preeclampsia (PE), endometriosis (EMs) and polycystic ovarian syndrome (PCOS). In the PE condition, the high sensitivity of trophoblasts towards ferroptosis has been found to potentially link to inflammation, suboptimal vascular remodeling and aberrant hemodynamics, which are three prominent pathophysiological features of PE. As for EMs, compromised ferroptosis of endometrial cells was associated with the formation ectopic lesions, whereas in the nearby lesions, the presence of ferroptosis was suggested to promote the progression of EMs, contributing to the relative clinical manifestations. Ferroptosis has been implicated a crucial role in the initiation of ovarian follicular atresia, which might help to manage ovulation in PCOS patients. Taken together, this review explored the basis of ferroptosis mechanisms and comprehensively summarized the latest discovery of roles of ferroptosis on PE, EMs and PCOS, gaining a deeper insight into the pathogenesis of these obstetrical and gynecological diseases and investigation of novel therapeutic interventions.

The interaction between ferroptosis and inflammatory signaling pathways

Ferroptosis is an iron-dependent regulated cell death driven by excessive lipid peroxidation. Inflammation is one common and effective physiological event that protects against various stimuli to maintain tissue homeostasis. However, the dysregulation of inflammatory responses can cause imbalance of the immune system, cell dysfunction and death. Recent studies have pointed out that activation of inflammation, including the activation of multiple inflammation-related signaling pathways, can lead to ferroptosis. Among the related signal transduction pathways, we focused on five classical inflammatory pathways, namely, the JAK-STAT, NF-κB, inflammasome, cGAS-STING and MAPK signaling pathways, and expounded on their roles in ferroptosis. To date, many agents have shown therapeutic effects on ferroptosis-related diseases by modulating the aforementioned pathways in vivo and in vitro. Moreover, the regulatory effects of these pathways on iron metabolism and lipid peroxidation have been described in detail, contributing to further understanding of the pathophysiological process of ferroptosis. Taken together, targeting these pathways related to inflammation will provide appropriate ways to intervene ferroptosis and diseases.

Novel druggable mechanism of Parkinson's disease: Potential therapeutics and underlying pathogenesis based on ferroptosis

Genetics, age, environmental factors, and oxidative stress have all been implicated in the development of Parkinson's disease (PD); however, a complete understanding of its pathology remains elusive. At present, there is no cure for PD, and currently available therapeutics are insufficient to meet patient needs. Ferroptosis, a distinctive iron-dependent cell death mode characterized by lipid peroxidation and oxidative stress, has pathophysiological features similar to those of PD, including iron accumulation, reactive oxygen species-induced oxidative damage, and mitochondrial dysfunction. Ferroptosis has been identified as a specific pathway of neuronal death and is closely related to the pathogenesis of PD. Despite the similarities in the biological targets involved in PD pathogenesis and ferroptosis, the relationship between novel targets in PD and ferroptosis has been neglected in the literature. In this review, the mechanism of ferroptosis is discussed, and the potential therapeutic targets implicated in both PD and ferroptosis are compared. Furthermore, the anti-PD effects of several ferroptosis inhibitors, as well as clinical studies thereof, and the identification of novel lead compounds for the treatment of PD and the inhibition of ferroptosis are reviewed. It is hoped that this review can promote research to further elucidate the relationship between ferroptosis and PD and provide new strategies for the development of novel ferroptosis-targeting PD therapy.

Role of ferroptosis in pregnancy related diseases and its therapeutic potential

Ferroptosis is a form of regulated cell death characterized by iron overload, overwhelming lipid peroxidation, and disruption of antioxidant systems. Emerging evidence suggests that ferroptosis is associated with pregnancy related diseases, such as spontaneous abortion, pre-eclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, and spontaneous preterm birth. According to these findings, inhibiting ferroptosis might be a potential option to treat pregnancy related diseases. This review summarizes the mechanisms and advances of ferroptosis, the pathogenic role of ferroptosis in pregnancy related diseases and the potential medicines for its treatment.

Resveratrol Improves the Cytotoxic Effect of CD8+T Cells in the Tumor Microenvironment by Regulating HMMR/Ferroptosis in Lung Squamous Cell Carcinoma

Ferroptosis, an iron-dependent cell death process, is a potential therapeutic strategy for Lung squamous cell carcinoma (LUSC). Resveratrol (RES) is an anti-tumor polyphenol. However, whether and how RES treats LUSC is not yet known. This study aimed to investigate the effect of RES on LUSC and to explore its potential mechanism. This study used a combination of proteomics, bioinformatics, clinical samples, and cell experiments to study the interaction between HMMR and the ferroptosis signaling pathway and investigate the role of RES in regulating tumor immune microenvironment and anti-tumor by cytotoxic CD8 +T cells in LUSC. Ferroptosis signaling pathway and HMMR were involved in the LUSC tumor immune microenvironment and correlated with worse prognosis of LUSC patients. RES+H520 cells induced a higher level of ferroptosis and MDA, mainly by reducing the expression of GPX4 and SLC7A11, inducing the expression of ACSL4 and TFRC. HMMR, GSH, and SOD contents were lower observed than in H520 cells. When HMMR was expressed, SLC7A11 was also highly expressed in LUSC, and there was an interaction between HMMR expression and SLC7A11. In addition, RES increased the TNF-α, IFN-γ, IL-12, and IL-2 expression and increased the cytotoxic effects of CD8 +T cells expressions in LUSC. Resveratrol regulates SLC7A11-HMMR interaction, activates ferroptosis, enhances the cytotoxic effect of CD8 +T cells, and regulates the tumor immune microenvironment. Based on the pathogenesis of LUSC and the clinical efficacy of RES, this study explored the influence of RES on LUSC, clarified its biological effects, and further provided cell biological basis for the clinical application of RES, which could guide clinical combination and personalized medicine, improve the response rate of immunotherapy and benefit more patients with LUSC.

NLRP3 inflammasome deficiency attenuates cerebral ischemia-reperfusion injury by inhibiting ferroptosis

BACKGROUND

The role of ferroptosis in ischemic stroke has been hotly debated recently, but the mechanism is not clearly clarified. It has been reported that the NLRP3 inflammasome is essential for the progression of ischemic stroke. Whether the ferroptosis after ischemic stroke mediated by the activation of NLRP3 inflammasome is still not reported. In this study, we investigated the effect of NLRP3 deficiency on ferroptosis following cerebral ischemia-reperfusion injury (CIRI) in vivo and in vitro.

MATERIALS

In vivo, we used C57BL/6J mice and NLRP3^-/- mice to establish a model of middle cerebral artery occlusion (MCAO). After 3 days of reperfusion, we assessed neurological function and then performed TTC staining to measure the infarct volume. Besides, we measured the expression of NLRP3 inflammasome-related proteins and the ferroptosis-inhibiting protein glutathione peroxidase 4 (GPX4) by western blotting (WB) and immunofluorescence (IF). Moreover, we evaluated the levels of ferroptosis-related factors (Fe²⁺, MDA and GSH) in the infarct area by using appropriate kits. Furthermore, we used WB to measure the expression of Kelch-like epichlorohydrin-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor 2 (Nrf2), which participate in the progression of ischemic stroke. In vitro, we knocked down NLRP3 with small interfering RNAs (siRNAs) and established an oxygen glucose deprivation/Reperfusion (OGD/R) model in BV2 cells to simulate ischemic conditions. Next, we assessed the viability of BV2 cells by the Cell Counting Kit (CCK)-8 cytotoxicity assay. Moreover, we used WB to measure the expression of NLRP3, IL-1β, GPX4, Keap1 and Nrf2 proteins which are involved in CIRI.

RESULTS

Three days after MCAO, the NLRP3^-/- mice exhibited smaller cerebral infarct volumes and lower neurological deficit scores. The expression of NLRP3 inflammasome-associated proteins (IL-18 and IL-1β) and Keap1/Nrf2 signaling pathway moleculars (Keap1 and Nrf2) in mice brain tissue and BV2 cells were inhibited by NLRP3 knockout/knockdown, while the expression of GPX4, one of the ferroptosis-related factors was increased. Furthermore, the contents of Fe²⁺ and MDA in the brain tissues of NLRP3^-/- mice were decreased, while the content of GSH were increased significantly.

CONCLUSION

Inhibition of the NLRP3 inflammasome alleviates CIRI by inhibiting ferroptosis and inflammation, possibly through a mechanism of the Keap1-Nrf2 pathway.

MicroRNAs: key regulators of the trophoblast function in pregnancy disorders

The placenta is essential for a successful pregnancy and healthy intrauterine development in mammals. During human pregnancy, the growth and development of the placenta are inseparable from the rapid proliferation, invasion, and migration of trophoblast cells. Previous reports have shown that the occurrence of many pregnancy disorders may be closely related to the dysfunction of trophoblasts. However, the function regulation of human trophoblast cells in the placenta is poorly understood. Therefore, studying the factors that regulate the function of trophoblast cells is necessary. MicroRNAs (miRNAs) are small, non-coding, single-stranded RNA molecules. Increasing evidence suggests that miRNAs play a crucial role in regulating trophoblast functions. This review outlines the role of miRNAs in regulating the function of trophoblast cells and several common signaling pathways related to miRNA regulation in pregnancy disorders.

Modulation of Nod-like Receptor Expression in the Thymus during Early Pregnancy in Ewes

Nucleotide-binding oligomerization domain receptors (NOD-like receptors, NLRs) are involved in modulating the innate immune responses of the trophoblast and the placenta in normal pregnancy. The thymus participates in regulation of innate and adaptive immune responses. However, it is unclear whether expression of NLR is modulated in the maternal thymus during early pregnancy. In this study, thymuses were sampled at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation (n = 6 for each group) from ewes after slaughter. Different stages were chosen because the maternal thymus was under the different effects of interferon-tau and/or progesterone or not. RT-qPCR, Western blot and immunohistochemistry analysis were used to analyze the expression of the NLR family, including NOD1; NOD2; major histocompatibility complex class II transactivator (CIITA); NLR family apoptosis inhibitory protein (NAIP); nucleotide-binding oligomerization domain and Leucine-rich repeat and Pyrin domain containing protein 1 (NLRP1), NLRP3 and NLRP7. The results showed that expression level of NOD1 was changed with the pregnancy stages, and expression levels of NOD2, CIITA, NAIP, NLRP1, NLRP3 and NLRP7 mRNA and proteins were peaked at day 13 of pregnancy. The levels of NOD2 and CIITA were increased during early pregnancy. The stainings for NOD2 and NLRP7 proteins were located in epithelial reticular cells, capillaries and thymic corpuscles. In summary, pregnancy stages changed expression of NLR family in the maternal thymus, which may be related to the modulation of maternal thymic immune responses, and beneficial for normal pregnancy in sheep.

Early Pregnancy Modulates Expression of the Nod-like Receptor Family in Lymph Nodes of Ewes

NOD receptors (NLRs) mediate adaptive immune responses and immune tolerance. Nevertheless, it is not clear if gestation modulates the NLR signaling pathway in lymph nodes of ewes. In this study, lymph nodes of ewes were collected at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation (n = 6 for each group). RT-qPCR, Western blot and immunohistochemistry analysis were used to analyze the expression of the NLR family, including NOD1, NOD2, CIITA, NAIP, NLRP1, NLRP3 and NLRP7. The data showed that early gestation enhanced expression of NOD1, CIITA, NLRP1, NLRP3 and NLRP7 mRNA, as well as proteins at day 16 of gestation, and the expression levels of NOD2, CIITA, NLRP1 and NLRP7 were higher at days 13 and 25 of gestation than day 16 of the estrous cycle. However, NOD1 expression was lower on days 13 and 25 of gestation compared to day 16 of the estrous cycle, and early gestation suppressed NAIP expression. In summary, early pregnancy modulated expression of the NLR family in ovine lymph nodes, which participates in immune regulation, and this modulation may be necessary for pregnancy establishment in ewes.

The Role of miRNAs in Dexmedetomidine's Neuroprotective Effects against Brain Disorders

There are limited neuroprotective strategies for various central nervous system conditions in which fast and sustained management is essential. Neuroprotection-based therapeutics have become an intensively researched topic in the neuroscience field, with multiple novel promising agents, from natural products to mesenchymal stem cells, homing peptides, and nanoparticles-mediated agents, all aiming to significantly provide neuroprotection in experimental and clinical studies. Dexmedetomidine (DEX), an α2 agonist commonly used as an anesthetic adjuvant for sedation and as an opioid-sparing medication, stands out in this context due to its well-established neuroprotective effects. Emerging evidence from preclinical and clinical studies suggested that DEX could be used to protect against cerebral ischemia, traumatic brain injury (TBI), spinal cord injury, neurodegenerative diseases, and postoperative cognitive disorders. MicroRNAs (miRNAs) regulate gene expression at a post-transcriptional level, inhibiting the translation of mRNA into functional proteins. In vivo and in vitro studies deciphered brain-related miRNAs and dysregulated miRNA profiles after several brain disorders, including TBI, ischemic stroke, Alzheimer's disease, and multiple sclerosis, providing emerging new perspectives in neuroprotective therapy by modulating these miRNAs. Experimental studies revealed that some of the neuroprotective effects of DEX are mediated by various miRNAs, counteracting multiple mechanisms in several disease models, such as lipopolysaccharides induced neuroinflammation, β-amyloid induced dysfunction, brain ischemic-reperfusion injury, and anesthesia-induced neurotoxicity models. This review aims to outline the neuroprotective mechanisms of DEX in brain disorders by modulating miRNAs. We address the neuroprotective effects of DEX by targeting miRNAs in modulating ischemic brain injury, ameliorating the neurotoxicity of anesthetics, reducing postoperative cognitive dysfunction, and improving the effects of neurodegenerative diseases.

Nanodiamond-Induced Thrombocytopenia in Mice Involve P-Selectin-Dependent Nlrp3 Inflammasome-Mediated Platelet Aggregation, Pyroptosis and Apoptosis

Nanodiamond (ND) has been developed as a carrier to conduct various in vivo diagnostic and therapeutic uses. Safety is one of the major considerations, while the hemocompatibility of ND is not clearly addressed. Here we found that, compared to the other sizes of ND with relatively inert properties, treatments of 50 nm ND induced stronger platelet aggregation, platelet pyroptosis, apoptosis and thrombocytopenia in mice. Blockage treatments of soluble P-selectin, reactive oxygen species (ROS), and Nlrp3 inflammasome inhibitors markedly suppressed such adverse effects, suggesting ND-induced platelet activation and pyroptosis involves surface P-selectin-mediated enhancement of mitochondrial superoxide levels and Nlrp3 inflammasome activation. In addition, challenges of NDs induced less platelet pyroptosis and displayed less thrombocytopenia in P-selectin (Selp^-/-), Nlrp3 (Nlrp3^-/-) and caspase-1 (Casp1^-/-) mutants, as compared to the wild type mice. Blockers of P-selectin, ROS, and Nlrp3 inflammasome pathways could be considered as antidotes for ND induced platelet activation and thrombocytopenia.

Bibliometric Analysis of Ferroptosis in Stroke From 2013 to 2021

Background: Stroke is a major cause of long-term disability and death, but the clinical therapeutic strategy for stroke is limited and more research must be conducted to explore the possible avenues for stroke treatment and recovery. Since ferroptosis is defined, its role in the body has become the focus of attention and discussion, including in stroke.

Methods: In this work, we aim to systematically discuss the “ferroptosis in stroke” research by bibliometric analysis. Documents were retrieved from the Web of Science Core Collection database on October 30, 2021. Statistical analysis and visualization analysis were conducted by the VOSviewer 1.6.15.

Results: Ninety-nine documents were identified for bibliometric analysis. Research on “ferroptosis in stroke” has been rapidly developing and has remained the focus of many scholars and organizations in the last few years, but the Chinese groups in this field still lacked collaboration with others. Documents and citation analysis suggested that Rajiv R. Ratan and Brent R. Stockwell are active researchers, and the research by Qingzhang Tuo, Ishraq Alim, and Qian Li are more important drivers in the development of the field. Keywords associated with lipid peroxidation, ferroptosis, iron, oxidative stress, and cell death had high frequency, but apoptosis, necroptosis, pyroptosis, and autophagy had scant research, and there may be more research ideas in the future by scholars.

Conclusion: Further exploration of the mechanisms of crosstalk between ferroptosis and other programmed cell death may improve clinical applications and therapeutic effects against stroke. Scholars will also continue to pay attention to and be interested in the hot topic “ferroptosis in stroke”, to produce more exciting results and provide new insights into the bottleneck of stroke treatment.