GhLCYε-3 characterized as a lycopene cyclase gene responding to drought stress in cotton

Drought stress significantly affects crop productivity. Carotenoids are essential photosynthetic pigment for plants, bacteria, and algae, with signaling and antioxidant functions. Lutein is a crucial branch product in the carotenoid synthesis pathway, which effectively improves the stress tolerance of higher plants. lycopene cyclase, a central enzyme for lutein synthesis, holds great significance in regulating lutein production. This research establishes a correlation between lutein content and stress resistance by measuring the drought resistance and lutein content of various cotton materials. To identify which crucial genes are associated with lutein, the lycopene cyclase family (LCYs) was analyzed. The research found that LCYs form a highly conserved family divided into two subfamilies, LCY-ε (lycopene ε-cyclase) and LCY-β (lycopene β-cyclase). Most members of the LCY family contain photoresponsive elements and abscisic acid elements. qRT-PCR demonstrates showed that most genes responded positively to drought stress, and GhLCYε-3 was expressed significantly differently under drought stress. Virus-induced gene silencing (VIGS) assay showed that the content of GhLCYε-3 was significantly increased with MDA and PRO, and the contents of chlorophyll and lutein were significantly decreased in pYL156 plants. The decrease in GhLCYε-3 expression is speculated to lead to reduced lutein content in vivo, resulting in the accumulation of reactive oxygen species (ROS) and decreased drought tolerance. This research enriched the understanding of LCY gene family and lutein function, and provided a new reference for cotton planting in arid areas.

Synopsis

Lycopene cyclase plays an important role in enhancing the ability of scavenging ROS and drought resistance of plants.

Imeglimin attenuates NLRP3 inflammasome activation by restoring mitochondrial functions in macrophages

Imeglimin is a novel oral antidiabetic drug for treating type 2 diabetes. However, the effect of imeglimin on NLRP3 inflammasome activation has not been investigated yet. Here, we aimed to investigate whether imeglimin reduces LPS-induced NLRP3 inflammasome activation in THP-1 macrophages and examine the associated underlying mechanisms. We analyzed the mRNA and protein expression levels of NLRP3 inflammasome components and IL-1β secretion. Additionally, reactive oxygen species (ROS) generation, mitochondrial membrane potential, and mitochondrial permeability transition pore (mPTP) opening were measured by flow cytometry. Imeglimin inhibited NLRP3 inflammasome-mediated IL-1β production in LPS-stimulated THP-1-derived macrophages. In addition, imeglimin reduced LPS-induced mitochondrial ROS production and mitogen-activated protein kinase phosphorylation. Furthermore, imeglimin restored the mitochondrial function by modulating mitochondrial membrane depolarization and mPTP opening. We demonstrated for the first time that imeglimin reduces LPS-induced NLRP3 inflammasome activation by inhibiting mPTP opening in THP-1 macrophages. These results suggest that imeglimin could be a promising new anti-inflammatory agent for treating diabetic complications.

Melanoma-associated melanocortin 1 receptor variants confer redox signaling-dependent protection against oxidative DNA damage

Cutaneous melanoma, a lethal skin cancer, arises from malignant transformation of melanocytes. Solar ultraviolet radiation (UVR) is a major environmental risk factor for melanoma since its interaction with the skin generates DNA damage, either directly or indirectly via oxidative stress. Pheomelanin pigments exacerbate oxidative stress in melanocytes by UVR-dependent and independent mechanisms. Thus, oxidative stress is considered to contribute to melanomagenesis, particularly in people with pheomelanic pigmentation. The melanocortin 1 receptor gene (MC1R) is a major melanoma susceptibility gene. Frequent MC1R variants (varMC1R) associated with fair skin and red or yellow hair color display hypomorphic signaling to the cAMP pathway and are associated with higher melanoma risk. This association is thought to be due to production of photosensitizing pheomelanins as well as deficient induction of DNA damage repair downstream of varMC1R. However, the data on modulation of oxidative DNA damage repair by MC1R remain scarce. We recently demonstrated that varMC1R accelerates clearance of reactive oxygen species (ROS)-induced DNA strand breaks in an AKT-dependent manner. Here we show that varMC1R also protects against ROS-dependent formation of 8-oxodG, the most frequent oxidative DNA lesion. Since the base excision repair (BER) pathway mediates clearance of these DNA lesions, we analyzed induction of BER enzymes in human melanoma cells of varMC1R genotype. Agonist-mediated activation of both wildtype (wtMC1R) and varMC1R significantly induced OGG and APE-1/Ref1, the rate-limiting BER enzymes responsible for repair of 8-oxodG. Moreover, we found that NADPH oxidase (NOX)-dependent generation of ROS was responsible for AKT activation and oxidative DNA damage repair downstream of varMC1R. These observations provide a better understanding of the functional properties of melanoma-associated MC1R alleles and may be useful for the rational development of strategies to correct defective varMC1R responses for efficient photoprotection and melanoma prevention in fair-skinned individuals.

Photo-Switchable Peroxidase/Catalase-Like Activity of Carbon Quantum Dots

Nanozymes possess multi-enzyme activities over the natural enzymes, which produce multi-pathway synergistic effects for varies of biomedical applications. Unfortunately, their multi-enzyme activities are in fighting, significantly reducing the synergistic effects. Dynamic regulation of their multi-enzyme activities is the bottleneck for intelligent therapies. Herein, we construct a novel oxygen-nitrogen functionalized carbon quantum dots (O/N-CQDs) with peroxidase-like (Reactive oxygen species (ROS) producer) activity. Interestingly, the peroxidase-like activity can be reversibly converted to catalase-like (ROS scavenger) activity under visible light irradiation. It is found that both the peroxidase/catalase-like activity of O/N-CQDs can be precisely manipulated by the light intensity. The mechanism of switchable enzyme activities is attributed to the polarization of quinoid nitrogen in polyaniline (PANI) precursor retained on O/N-CQDs under visible light, which consumes the ROS to produce O2 and H2O. As a proof-of-concept demonstration, we are able to non-intrusively up and down regulate the ROS level in cells successfully by simply switching off and on the light respectively, potentially facilitating the precise medicine based on the development of the disease. Indeed, the photo-switchable peroxidase/catalase-like activity of O/N-CQDs opens a non-invasive strategy for better manipulations of the multi-activity of nanozymes, promising their wider and more intelligent biomedical applications.

Proline inhibits postharvest physiological deterioration of cassava by improving antioxidant capacity

Cassava (Manihot esculenta Crantz), a crucial global tuber crop, encounters significant economic losses attributed to postharvest physiological deterioration (PPD). The PPD phenomenon in cassava is closely related to the accumulation of reactive oxygen species (ROS), and amino acids play a pivotal role in regulating signaling pathways and eliminating ROS. In this study, the storage performance of eight cassava varieties were conducted. Cassava cultivar SC5 showed the best storage performance among the eight cassava varieties, but the edible cassava cultivar SC9 performed much worse. Comparative analysis of free amino acids was conducted in eight cassava varieties, revealing changes in proline, aspartic acid, histidine, glutamic acid, threonine, and serine. Exogenous supplementation of these six amino acids was performed to inhibit PPD of SC9. Proline was confirmed as the key amino acid for inhibiting PPD. Treatment with optimal exogenous proline of 5 g/L resulted in a 17.9% decrease in the deterioration rate compared to untreated cassava. Accompanied by a decrease in H2O2 content and an increase in catalase, superoxide dismutase and ascorbate peroxidase activity. Proline treatment proved to be an effective approach to alleviate cell oxidative damage, inhibit PPD in cassava, and prolong shelf life.

OsBBP1, a newly identified protein containing DUF630 and DUF632 domains confers drought tolerance in rice

Domain of unknown function (DUF) protein families, which are uncharacterized and numerous within the Pfam database. Recently, studies have demonstrated that DUFs played crucial roles in plant development, but whether, or how, they function in drought resistance remain unclear. In this study, we identified the Os03g0321500 gene, encoding OsbZIP72 binding protein 1 (OsBBP1), as a target of OsbZIP72 using chromatin immunoprecipitation sequencing in rice. OsBBP1 is a novel member of DUFs, which localize both in the nuclei and cytoplasm of rice protoplasts. Furthermore, yeast one-hybrid and electrophoretic mobility shift assays confirmed the specific binding between OsbZIP72 and OsBBP1. Additionally, a luciferase reporter analysis illustrated that OsbZIP72 activated the expression of OsBBP1. Drought tolerance experiments demonstrate that the OsBBP1 CRISPER-CAS9 transgenic mutants were sensitive to drought stress, but the transgenic OsBBP1 over-expressing rice plants showed enhanced drought resistance. Moreover, drought tolerance experiments in a paddy field suggested that OsBBP1 contributed to less yield or yield-related losses under drought conditions. Mechanistically, OsBBP1 might confer drought resistance by inducing more efficient reactive oxygen species (ROS) scavenging. Several ROS scavenging-related genes showed increased expression levels in OsBBP1 overexpression lines and decreased expression levels in OsBBP1 CRISPER-CAS9 mutants under drought conditions. Thus, OsBBP1, acting downstream of OsbZIP72, contributes to drought resistance and causes less yield or yield-related losses under drought conditions.

A novel aldo-keto reductase gene, OsAKR1, from rice confers higher tolerance to cadmium stress in rice by an in vivo reactive aldehyde detoxification

Elevated levels of cadmium (Cd) have the ability to impede plant development. Aldo-keto reductases (AKRs) have been demonstrated in a number of plant species to improve tolerance to a variety of abiotic stresses by scavenging cytotoxic aldehydes; however, only a few AKRs have been identified to improve Cd tolerance. The OsAKR1 gene was extracted and identified from rice here. After being exposed to Cd, the expression of OsAKR1 dramatically rose in both roots and shoots, although more pronounced in roots. According to a subcellular localization experiment, the nucleus and cytoplasm are where OsAKR1 is primarily found. Mutants lacking OsAKR1 exhibited Cd sensitive phenotype than that of the wild-type (WT) Nipponbare (Nip), and osakr1 mutants exhibited reduced capacity to scavenge methylglyoxal (MG). Furthermore, osakr1 mutants exhibited considerably greater hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels, and increased catalase (CAT) activity in comparison to Nip. The expression of three isomeric forms of CAT was found to be considerably elevated in osakr1 mutants during Cd stress, as demonstrated by quantitative real-time PCR analysis, when compared to Nip. These results imply that OsAKR1 controlled rice's ability to withstand Cd by scavenging harmful aldehydes and turning on the reactive oxygen species (ROS) scavenging mechanism.

Triiodo-L-thyronine (T3) downregulates Npr1 gene (coding for natriuretic peptide receptor-A) transcription in H9c2 cells: involvement of β-AR-ROS signaling

INTRODUCTION

Natriuretic peptide receptor-A (NPR-A) signaling system is considered as an intrinsic productive mechanism of the heart that opposes abnormal cardiac remodeling and hypertrophic growth. NPR-A is coded by Npr1 gene, and its expression is downregulated in the hypertrophied heart.

AIM

We sought to examine the levels of Npr1 gene transcription in triiodo-L-thyronine (T3) treated hypertrophied cardiomyocyte (H9c2) cells, in vitro, and also the involvement of β-adrenergic receptor (β-AR) - Reactive oxygen species (ROS) signaling system in the down-regulation of Npr1 transcription also studied.

MAIN METHODS

Anti-hypertrophic Npr1 gene transcription was monitored in control and T3-treated (dose and time dependent) H9c2 cells, using a real time PCR method. Further, cell size, intracellular cGMP, ROS, hypertrophy markers (ANP, BNP, α-sk, α-MHC and β-MHC), β-AR, and protein kinase cGMP-dependent 1 (PKG-I) genes expression were also determined. The intracellular cGMP and ROS levels were determined by ELISA and DCF dye method, respectively. In addition, to neutralize T3 mediated ROS generation, H9c2 cells were treated with T3 in the presence and absence of antioxidants [curcumin (CU) or N-acetyl-L-cysteine (NAC)].

RESULTS

A dose dependent (10 pM, 100 pM, 1 nM and 10 nM) and time dependent (12 h, 24 h and 48 h) down-regulation of Npr1 gene transcription (20, 39, 60, and 74% respectively; 18, 55, and 85%, respectively) were observed in T3-treated H9c2 cells as compared with control cells. Immunofluorescence analysis also revealed that a marked down regulation of NPR- A protein in T3-treated cells as compared with control cells. Further, a parallel downregulation of cGMP and PKG-I (2.4 fold) were noticed in the T3-treated cells. In contrast, a time dependent increased expression of β-AR (60, 72, and 80% respectively) and ROS (26, 48, and 74%, respectively) levels were noticed in T3-treated H9c2 cells as compared with control cells. Interestingly, antioxidants, CU or NAC co-treated T3 cells displayed a significant reduction in ROS (69 and 81%, respectively) generation and to increased Npr1 gene transcription (81 and 88%, respectively) as compared with T3 alone treated cells.

CONCLUSION

Our result suggest that down regulation of Npr1 gene transcription is critically involved in T3- induced hypertrophic growth in H9c2 cells, and identifies the cross-talk between T3-β-AR-ROS and NPR-A signaling.

circ_WASF2 regulates ferroptosis by miR-634/ GPX4 signaling in pancreatic cancer

PURPOSE

Pancreatic cancer (PC) is one of the most lethal malignant gastrointestinal tumors (GI) characterized by a poor prognosis. Ferroptosis is an emerging programmed cell death that plays an essential role in the progression of various cancers. Ferroptosis is driven by iron-dependent phospholipid peroxidation and is regulated by mitochondrial activity, lipid peroxidation, and reactive oxygen species (ROS). The function and mechanism of ferroptosis in PC need more research.

METHODS

The levels of circRNAs, miRNAs, and mRNAs were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was used for protein detection. CCK8 assays were used to detect cell proliferation. Cell death, lipid peroxidation, ROS, and Fe2+ were detected by indicted kits. Dual-luciferase reporter and RNA pull-down assays were conducted to confirm the interaction between circRNAs, miRNAs, and mRNAs.

RESULTS

In this research, we found that circular RNA hsa_circ_0000003(circ_WASF2) was upregulated in pancreatic cancer cells. The silence of circ_WASF2 inhibited cancer proliferation and increased cell death by increasing ferroptosis accompanied by up-regulation of lipid peroxidation, ROS, and Fe2+. Further studies showed that circ_WASF2 could attenuate ferroptosis by targeting miR-634 and the downstream glutathione peroxidase 4 (GPX4). GPX4 has been well-reported as a central factor in ferroptosis. Our research revealed a new pathway for regulating ferroptosis in PC.

CONCLUSION

In summary, we have determined that circ_WASF2/miR-634/GPX4 contributed to ferroptosis-induced cell death, and provided a possible therapeutic target in PC.

Metabolic dysfunction-associated steatohepatitis treated by poly(ethylene glycol)-block-poly(cysteine) block copolymer-based self-assembling antioxidant nanoparticles

Non-alcoholic steatohepatitis (NASH), now known as metabolic dysfunction-associated steatohepatitis (MASH), involves oxidative stress caused by the overproduction of reactive oxygen species (ROS). Small-molecule antioxidants have not been approved for antioxidant chemotherapy because of severe adverse effects that collapse redox homeostasis, even in healthy tissues. To overcome these disadvantages, we have been developing poly(ethylene glycol)-block-poly(cysteine) (PEG-block-PCys)-based self-assembling polymer nanoparticles (NanoCyses), releasing Cys after in vivo degradation by endogenous enzymes, to obtain antioxidant effects without adverse effects. However, a comprehensive investigation of the effects of polymer design on therapeutic outcomes has not yet been conducted to develop our NanoCys system for antioxidant chemotherapy. In this study, we synthesized different poly(L-cysteine) (PCys) chains whose sulfanyl groups were protected by tert-butyl thiol (StBu) and butyryl (Bu) groups to change the reactivity of the side chains, affording NanoCys(SS) and NanoCys(Bu), respectively. To elucidate the importance of the polymer design, these NanoCyses were orally administered to MASH model mice as a model of oxidative stress-related diseases. Consequently, the acyl-protective NanoCys(Bu) significantly suppressed hepatic lipid accumulation and oxidative stress compared to NanoCys(SS). Furthermore, we substantiated that shorter PCys were much better than longer PCys for therapeutic outcomes and the effects related to the liberation properties of Cys from these nanoparticles. Owing to its antioxidant functions, NanoCyses also significantly attenuated hepatic inflammation and fibrosis in the MASH mouse model.

Dihydroartemisinin, a potential PTGS1 inhibitor, potentiated cisplatin-induced cell death in non-small cell lung cancer through activating ROS-mediated multiple signaling pathways

Dihydroartemisinin (DHA) exerts an anti-tumor effect in multiple cancers, however, the molecular mechanism of DHA and whether DHA facilitates the anti-tumor efficacy of cisplatin in non-small cell lung cancer (NSCLC) are unclear. Here, we found that DHA potentiated the anti-tumor effects of cisplatin in NSCLC cells by stimulating reactive oxygen species (ROS)-mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 MAPK signaling pathways both in vitro and in vivo. Of note, we demonstrated for the first time that DHA inhibits prostaglandin G/H synthase 1 (PTGS1) expression, resulting in enhanced ROS production. Importantly, silencing PTGS1 sensitized DHA-induced cell death by increasing ROS production and activating ER-stress, JNK and p38 MAPK signaling pathways. In summary, our findings provided new experimental basis and therapeutic prospect for the combined therapy with DHA and cisplatin in some NSCLC patients.

Mechanical stress induced mitochondrial dysfunction in cardiovascular diseases: Novel mechanisms and therapeutic targets

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Others and our studies have shown that mechanical stresses (forces) including shear stress and cyclic stretch, occur in various pathological conditions, play significant roles in the development and progression of CVDs. Mitochondria regulate the physiological processes of cardiac and vascular cells mainly through adenosine triphosphate (ATP) production, calcium flux and redox control while promote cell death through electron transport complex (ETC) related cellular stress response. Mounting evidence reveal that mechanical stress-induced mitochondrial dysfunction plays a vital role in the pathogenesis of many CVDs including heart failure and atherosclerosis. This review summarized mitochondrial functions in cardiovascular system under physiological mechanical stress and mitochondrial dysfunction under pathological mechanical stress in CVDs (graphical abstract). The study of mitochondrial dysfunction under mechanical stress can further our understanding of the underlying mechanisms, identify potential therapeutic targets, and aid the development of novel treatments of CVDs.

Genome-wide identification and characterization of the sweet orange (Citrus sinensis) basic helix-loop-helix (bHLH) family reveals a role for CsbHLH085 as a regulator of citrus bacterial canker resistance

Citrus bacterial canker (CBC) is a harmful bacterial disease caused by Xanthomonas citri subsp. citri (Xcc), negatively impacting citrus production worldwide. The basic helix-loop-helix (bHLH) transcription factor family plays crucial roles in plant development and stress responses. This study aimed to identify and annotate bHLH proteins encoded in the Citrus sinensis genome and explore their involvement and functional importance in regulating CBC resistance. A total of 135 putative CsbHLHs TFs were identified and categorized into 16 subfamilies. Their chromosomal locations, collinearity, and phylogenetic relationships were comprehensively analyzed. Upon Xcc strain YN1 infection, certain CsbHLHs were differentially regulated in CBC-resistant and CBC-sensitive citrus varieties. Among these, CsbHLH085 was selected for further functional characterization. CsbHLH085 was upregulated in the CBC-resistant citrus variety, was localized in the nucleus, and had a transcriptional activation activity. CsbHLH085 overexpression in Citrus significantly enhanced CBC resistance, accompanied by increased levels of salicylic acid (SA), jasmonic acid (JA), reactive oxygen species (ROS), and decreased levels of abscisic acid (ABA) and antioxidant enzymes. Conversely, CsbHLH085 virus-induced gene silencing resulted in opposite phenotypic and biochemical responses. CsbHLH085 silencing also affected the expression of phytohormone biosynthesis and signaling genes involved in SA, JA, and ABA signaling. These findings highlight the crucial role of CsbHLH085 in regulating CBC resistance, suggesting its potential as a target for biotechnological-assisted breeding citrus varieties with improved resistance against phytopathogens.

Exploration of novel isoxazole-fused quinone derivatives as anti-colorectal cancer agents through inhibiting STAT3 and elevating ROS level

Colorectal cancer (CRC) is trending to be a major health problem throughout the world. Therapeutics with dual modes of action have shown latent capacity to create ideal anti-tumor activity. Signal transducer and activator of transcription 3 (STAT3) has been proved to be a potential target for the development of anti-colon cancer drug. In addition, modulation of tumor redox homeostasis through deploying exogenous reactive oxygen species (ROS)-enhancing agents has been widely applied as anti-tumor strategy. Thus, simultaneously targeting STAT3 and modulation ROS balance would offer a fresh avenue to combat CRC. In this work, we designed and synthesized a novel series of isoxazole-fused quinones, which were evaluated for their preliminary anti-proliferative activity against HCT116 cells. Among these quinones, compound 41 exerted excellent in vitro anti-tumor effect against HCT116 cell line with an IC50 value of 10.18 ± 0.4 nM. Compound 41 was proved to bind to STAT3 by using Bio-Layer Interferometry (BLI) assay, and can significantly inhibit phosphorylation of STAT3. It also elevated ROS of HCT116 cells by acting as a substrate of NQO1. Mitochondrial dysfunction, apoptosis, and cell cycle arrest, which was caused by compound 41, might be partially due to the inhibition of STAT3 phosphorylation and ROS production induced by 41. Moreover, it exhibited ideal anti-tumor activity in human colorectal cancer xenograft model and good safety profiles in vivo. Overall, this study provided a novel quinone derivative 41 with excellent anti-tumor activity by inhibiting STAT3 and elevating ROS level, and gave insights into designing novel anti-tumor therapeutics by simultaneously modulation of STAT3 and ROS.

Beta hydroxybutyrate induces lung cancer cell death, mitochondrial impairment and oxidative stress in a long term glucose-restricted condition

BACKGROUND

Metabolic plasticity gives cancer cells the ability to shift between signaling pathways to facilitate their growth and survival. This study investigates the role of glucose deprivation in the presence and absence of beta-hydroxybutyrate (BHB) in growth, death, oxidative stress and the stemness features of lung cancer cells.

METHODS AND RESULTS

A549 cells were exposed to various glucose conditions, both with and without beta-hydroxybutyrate (BHB), to evaluate their effects on apoptosis, mitochondrial membrane potential, reactive oxygen species (ROS) levels using flow cytometry, and the expression of CD133, CD44, SOX-9, and β-Catenin through Quantitative PCR. The activity of superoxide dismutase, glutathione peroxidase, and malondialdehyde was assessed using colorimetric assays. Treatment with therapeutic doses of BHB triggered apoptosis in A549 cells, particularly in cells adapted to glucose deprivation. The elevated ROS levels, combined with reduced levels of SOD and GPx, indicate that oxidative stress contributes to the cell arrest induced by BHB. Notably, BHB treatment under glucose-restricted conditions notably decreased CD133 expression, suggesting a potential inhibition of cell survival through the downregulation of CD133 levels. Additionally, the simultaneous decrease in mitochondrial membrane potential and increase in ROS levels indicate the potential for creating oxidative stress conditions to impede tumor cell growth in such environmental settings.

CONCLUSION

The induced cell death, oxidative stress and mitochondria impairment beside attenuated levels of cancer stem cell markers following BHB administration emphasize on the distinctive role of metabolic plasticity of cancer cells and propose possible therapeutic approaches to control cancer cell growth through metabolic fuels.

What can reactive oxygen species (ROS) tell us about the action mechanism of herbicides and other phytotoxins?

Reactive oxygen species (ROS) are formed in plant cells continuously. When ROS production exceeds the antioxidant capacity of the cells, oxidative stress develops which causes damage of cell components and may even lead to the induction of programmed cell death (PCD). The levels of ROS production increase upon abiotic stress, but also during pathogen attack in response to elicitors, and upon application of toxic compounds such as synthetic herbicides or natural phytotoxins. The commercial value of many synthetic herbicides is based on weed death as result of oxidative stress, and for a number of them, the site and the mechanism of ROS production have been characterized. This review summarizes the current knowledge on ROS production in plants subjected to different groups of synthetic herbicides and natural phytotoxins. We suggest that the use of ROS-specific fluorescent probes and of ROS-specific marker genes can provide important information on the mechanism of action of these toxins. Furthermore, we propose that, apart from oxidative damage, elicitation of ROS-induced PCD is emerging as one of the important processes underlying the action of herbicides and phytotoxins.

ROS are universal cell-to-cell stress signals

The interplay between reactive oxygen species (ROS) and the redox state of cells is deeply rooted in the biology of almost all organisms, regulating development, growth, and responses to the environment. Recent studies revealed that the ROS levels and redox state of one cell can be transmitted, as an information 'state' or 'currency', to other cells and spread by cell-to-cell communication within an entire community of cells or an organism. Here, we discuss the different pathways that mediate cell-to-cell signaling in plants, their hierarchy, and the different mechanisms that transmit ROS/redox signaling between different cells. We further hypothesize that ROS/redox signaling between different organisms could play a key role within the 'one world' principle, impacting human health and our future.

Natural endoperoxides as promising anti-leishmanials

BACKGROUND

The discovery of artemisinin, an endoperoxide, encouraged the scientific community to explore endoperoxides as potential anti-parasitic molecules. Although artemisinin derivatives are rapidly evolving as potent anti-malarials, their potential as anti-leishmanials is emerging gradually. The treatment of leishmaniasis, a group of neglected tropical diseases is handicapped by lack of effective vaccines, drug toxicities and drug resistance. The weak antioxidant defense mechanism of the Leishmania parasites due to lack of catalase and a selenium dependent glutathione peroxidase system makes them vulnerable to oxidative stress, and this has been successful exploited by endoperoxides.

PURPOSE

The study aimed to review the available literature on the anti-leishmanial efficacy of natural endoperoxides with a view to achieve insights into their mode of actions.

METHODS

We reviewed more around 110 research and review articles restricted to the English language, sourced from electronic bibliographic databases including PubMed, Google, Web of Science, Google scholar etc. RESULTS: Natural endoperoxides could potentially augment the anti-leishmanial drug library, with artemisinin and ascaridole emerging as potential anti-leishmanial agents. Due to higher reactivity of the cyclic peroxide moiety, and exploiting the compromised antioxidant defense of Leishmania, endoperoxides like artemisinin and ascaridole potentiate their leishmanicidal efficacy by creating a redox imbalance. Furthermore, these molecules minimally impair oxidative phosphorylation; instead inhibit glycolytic functions, culminating in depolarization of the mitochondrial membrane and depletion of ATP. Additionally, the carbon-centered free radicals generated from endoperoxides, participate in chain reactions that can generate even more reactive organic radicals that are toxic to macromolecules, including lipids, proteins and DNA, leading to cell cycle arrest and apoptosis of Leishmania parasites. However, the precise target(s) of the toxic free radicals remains open-ended.

CONCLUSION

In this overview, the spectrum of natural endoperoxide molecules as major anti-leishmanials and their mechanism of action has been delineated. In view of the substantial evidence that natural endoperoxides (e.g., artemisinin, ascaridole) exert a noxious effect on different species of Leishmania, identification and characterization of other natural endoperoxides is a promising therapeutic option worthy of further pharmacological consideration.

Compounding Methylene Blue with Selenium-decorated Graphene Quantum Dots to Improve Singlet Oxygen Production for Photodynamic Therapy Application

Graphene quantum dots (GQDs) are known as suitable material to be applied in different fields such as photodynamic therapy (PDT). Herein, GQDs were synthesized by the pyrolysis method and then decorated with selenium (Se). Afterward, they were combined with methylene blue (MB) to increase singlet oxygen generation as well as to apply them more effectively in the PDT method. Furthermore, GQDs were investigated by transmission electron microscope (TEM), photoluminescence spectrum (PL), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM), reactive oxygen species (ROS) measurement, and cytotoxicity measurement. GQDs showed no dependence on the excitation wavelength. The result of ROS measurement proves that the combination of GQD-Se and MB increases singlet oxygen production. Moreover, afterglow measurement approved the beneficial effect of GQD-Se on even deep and near skin tumor treatment. Cytotoxicity measurements under dark conditions, cell viability, and the side effects on human cells were determined by (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) (MTT) assay. Our findings show that under dark conditions, even high concentrations of nanoparticles have no significant effect on cell viability. These findings and the high biocompatibility of GQDs indicate the effective application of GQD-Se-MB in PDT.

ROS-responsive sprayable hydrogel as ROS scavenger and GATA6+ macrophages trap for the prevention of postoperative abdominal adhesions

Postoperative abdominal adhesions are a common clinical problem after surgery and can cause many serious complications. Current most commonly used antiadhesion products are less effective due to their short residence time and focus primary on barrier function. Herein, we developed a sprayable hydrogel barrier (sHA-ADH/OHA-E) with self-regulated drug release based on ROS levels at the trauma site, to serve as a smart inflammatory microenvironment modulator and GATA6+ macrophages trap for non-adherent recovery from abdominal surgery. Sulfonated hyaluronic acid (HA) conjugates modified with adipic dihydrazide (sHA-ADH), and oxidized HA conjugates grafted with epigallocatechin-3-gallate (EGCG) via ROS-cleavable boronate bonds (OHA-E) were synthesized. sHA-ADH/OHA-E hydrogel was facilely fabricated within 5 s after simply mixing sHA-ADH and OHA-E through forming dynamic covalent acylhydrazones. With good biocompatibility, appropriate mechanical strength, tunable shear-thinning, self-healing, asymmetric adhesion, and reasonable in vivo retention time, sHA-ADH/OHA-E hydrogel meets the requirements of a perfect physical barrier. Intriguingly, sulfonic acid groups endowed the hydrogel with satisfactory anti-fibroblast and macrophage attachment capability, and were demonstrated for the first time to act as polyanion traps to prevent GATA6+ macrophages aggregation. Importantly, EGCG could be intelligently released by ROS triggering to alleviate oxidative stress and promote proinflammatory M1 macrophage polarize to antiinflammatory M2 phenotype. Further, the fibrinolytic system balance was restored to reduce fibrosis. Thanks to the above advantages, the sHA-ADH/OHA-E hydrogel exhibited excellent anti-adhesion effects in a rat sidewall defect-cecum abrasion model and is expected to be a promising and clinically translatable antiadhesion barrier.

Transcriptomic analysis reveals mitochondrial dysfunction in the pathogenesis of Nager syndrome in sf3b4-depleted zebrafish

Nager syndrome (NS) is a rare acrofacial dysostosis caused by heterozygous loss-of-function variants in the splicing factor 3B subunit 4 (SF3B4). The main clinical features of patients with NS are characterized by facial-mandibular and preaxial limb malformations. The migration and specification of neural crest cells are crucial for craniofacial development, and mitochondrial fitness appears to play a role in such processes. Here, by analyzing our previously published transcriptome dataset, we aim to investigate the potential involvement of mitochondrial components in the pathogenesis of craniofacial malformations, especially in sf3b4 mutant zebrafish. We identified that oxidative phosphorylation (OXPHOS) defects and overproduction of reactive oxygen species (ROS) due to decreased antioxidants defense activity, which leads to oxidative damage and mitochondrial dysfunction. Furthermore, our results highlight that fish lacking sf3b4 gene, primarily display defects in mitochondrial complex I. Altogether, our findings suggest that mitochondrial dysfunction may contribute to the development of the craniofacial anomalies observed in sf3b4-depleted zebrafish.

BRCA1 protein dose-dependent risk for embryonic oxidative DNA damage, embryopathies and neurodevelopmental disorders with and without ethanol exposure

Although widely known as a tumor suppressor, the breast cancer 1 susceptibility protein (BRCA1) is also important in development, where it regulates fetal DNA repair pathways that protect against DNA damage caused by physiological and drug-enhanced levels of reactive oxygen species (ROS). We previously showed that conditional heterozygous (+/-) knockout (cKO) mouse embryos with a minor 28% BRCA1 deficiency developed normally in culture, but when exposed to the ROS-initiating drug, alcohol (ethanol, EtOH), exhibited embryopathies not evident in wild-type (+/+) littermates. Herein, we characterized a directBrca1 +/- knockout (KO) model with a 2-fold greater (58%) reduction in BRCA1 protein vs. the cKO model. We also characterized and compared learning & memory deficits in both the cKO and KO models. Even saline-exposed Brca1 +/- vs. +/+ KO progeny exhibited enhanced oxidative DNA damage and embryopathies in embryo culture and learning & memory deficits in females in vivo, which were not observed in the cKO model, revealing the potential pathogenicity of physiological ROS levels. The embryopathic EtOH concentration for cultured direct KO embryos was half that for cKO embryos, and EtOH affected Brca1 +/+ embryos only in the direct KO model. The spectrum and severity of EtOH embryopathies in culture were greater in both Brca1 +/- vs. +/+ embryos, and direct KO vs. cKO +/- embryos. Motor coordination deficits were evident in both male and female Brca1 +/- KO progeny exposed in utero to EtOH. The results in our direct KO model with a greater BRCA1 deficiency vs. cKO mice provide the first evidence for BRCA1 protein dose-dependent susceptibility to developmental disorders caused by physiological and drug-enhanced oxidative stress.

Injectable biocompatible RAFT mediated nitroxide nanogels: A robust ROS-reduction antioxidant approach

This work introduces novel nitroxide-based nanogels (NGs) crafted through controlled RAFT (Reversible Addition Fragmentation chain Transfer) polymerization, showcasing over 85% improved shelf-life compared to native superoxide dismutase (SOD) enzymes. These 30-40 nm NGs hold great promise for injectable delivery, effectively reducing foam cell formation and displaying potent antioxidant behavior against various reactive oxygen species (ROS), revolutionizing antioxidant therapy. Featuring a meticulously designed core-shell structure via precise RAFT polymerization, these NGs mimic SOD enzymatic activity with nitroxide-based antioxidants, providing unprecedented defense against ROS. Combining methacrylated 2,2,6,6-Tetramethyl-4-piperidyl methacrylate (PMA) and Glycidyl methacrylate (GMA) monomers with precisely synthesized nitroxyl radicals results in exceptional properties. Validated through comprehensive analytical methods, these NGs exhibit remarkable stability, halting foam cell formation even at high concentrations, and demonstrate notable biocompatibility. Their ability to protect low density lipoprotein (LDL) from oxidation for up to a month positions them at the forefront of combating cardiovascular diseases, especially atherosclerosis. This study pioneers injectable antioxidant therapy, offering an innovative approach to cardiovascular ailments. Targeting narrow plaques signifies a promising intervention, reshaping cardiovascular disease treatments. It highlights the potential of advanced drug delivery in biomedicine, promising more effective cardiovascular disease treatments.

Biotoxicity responses of zebrafish in environmentally relevant concentration of di (2-ethylhexyl) phthalate

As an emerging environmental contaminant, di (2-ethylhexyl) phthalate (DEHP) is widely present in the aquatic environment, however, the effects and underlying mechanisms of DEHP on the aquatic organisms are poorly understood. This study systematically investigated the ecotoxicity induced by chronic exposure to environmental relevant concentrations of DEHP (0.03 mg/L, 0.1 mg/L, and 0.3 mg/L) on zebrafish brain. Results indicated that DEHP exposure significantly increased the levels of ROS and disturbance of the antioxidant enzymes activities in the brain, which may further enhance lipid peroxidation and DNA damage. Furthermore, acetylcholinesterase activity was first stimulated and inhibited by exposure to DEHP, and the antioxidant and apoptosis related genes were mainly upregulated. Risk assessment indicated that the ecotoxicity of DEHP on the zebrafish showed an "enhancement-reduction" trend as the exposure time was prolonged. Overall, these results provided new insights and useful information to ecological risk assessment and environmental management of DEHP pollution.

The development of logic gate-based fluorescent probes that respond to intracellular hydrogen peroxide and pH in tandem

Logic gate-based fluorescent probes are powerful tools for the discriminative sensing of multiple signaling molecules that are expressed in concert during the progression of many diseases such as inflammation, cancer, aging, and other disorders. To achieve logical sensing, multiple functional groups are introduced to the different substitution sites of a single fluorescent dye, which increases the complexity of chemical synthesis. Herein, we report a simple strategy that incorporates just one responsive unit into a hemicyanine dye achieving the logic gate-based sensing of two independent analytes. We introduce boronic acid to hemicyanine to quench the fluorescence, and in the presence of hydrogen peroxide (H2O2), the fluorescence is recovered due to removal of the boronate. Interestingly, the subsequent decrease in pH turned the red fluorescence of hemicyanine to green emissive because of protonation of the phenolic alcohol. This unique feature of the probe enables us to construct "INHIBIT" and "AND" logical gates for the accurate measuring of intracellular H2O2 and acidic pH in tandem. This study offers insight into the simple construction of logic-gate based fluorescent probes for the tandem sensing of multiple analytes that are correlatively produced during disease progression.

Targeted pH- and redox-responsive AuS/micelles with low CMC for highly efficient sonodynamic therapy of metastatic breast cancer

The efficacy of injectable micellar carriers is hindered due to the disassembly of micelles into free surfactants in the body, resulting in their dilution below the critical micelle concentration (CMC). Copolymer micelles were developed to address this issue, containing a superhydrophilic zwitterionic block and a superhydrophobic block with a disulfide bond, which exhibited a CMC lower than conventional micellar carriers. Cleavable copolymers composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) zwitterion and polycaprolactone CHLZW as the shell, with gold nanoparticles as their core, were studied to deliver doxorubicin to tumor cells while reducing the side effect of the free cytotoxic agent. The research focused on the impact of gold nanoparticles present in targeted TMT-micelles core on stability and in vivo bioavailability and sonotoxicity of the nanoparticles, as well as their synergistic effect on targeted chemotherapy. The nanomicelles prepared in this study demonstrated excellent biocompatibility and responsiveness to stimuli. PCL-SS-MPC nanomicelles displayed drug release in response to GSH and pH, resulting in high DOX release at GSH 10 mM and pH 5. Our findings, supported by MTT, flow cytometry, and confocal laser scanning microscopy, demonstrated that AuS-PM-TMTM-DOX micelles effectively induced apoptosis and enhanced cellular uptake in MCF7 and MDA-MB231 cell lines. The cytotoxic effects of AuS-PM-DOX/US on cancer cells were approximately 38 % higher compared to AuS-PM-DOX samples at a concentration of IC50 0.68 nM. This increase in cellular toxicity was primarily attributed to the promotion of apoptosis. The introduction of disulfide linkages in AuSNPs resulted in increased ROS production when exposed to ultrasound stimulation, due to a reduction in GSH levels. Compared to other commercially available nanosensitizers such as titanium dioxide, exposure of AuS-PM to ultrasound radiation (1.0 W/cm, 2 min) significantly enhanced cavitation effects and resulted in 3 to 5 times higher ROS production. Furthermore, laboratory experiments using human breast cancer cells (MDA-MB-231, MCF7) demonstrated that the toxicity of AuS-PM in response to ultrasound waves is dose-dependent. The findings of this study suggest that this formulated nanocarrier holds great potential as a viable treatment option for breast cancer. It can induce apoptosis in cancer cells, reduce tumor size, and display notable therapeutic efficacy.

Reactive oxygen species augment contractile responses of saphenous artery in 10-15-day-old but not adult rats: Substantial role of NADPH oxidases

Reactive oxygen species (ROS) produced by NADPH oxidases (NOX, a key source of ROS in vascular cells) are involved in the regulation of vascular tone, but this has been explored mainly for adult organisms. Importantly, the mechanisms of vascular tone regulation differ significantly in early postnatal ontogenesis and adulthood, while the vasomotor role of ROS in immature systemic arteries is poorly understood. We tested the hypothesis that the functional contribution of NADPH oxidase-derived ROS to the regulation of peripheral arterial tone is higher in the early postnatal period than in adulthood. We studied saphenous arteries from 10- to 15-day-old ("young") and 3- to 4-month-old ("adult") male rats using lucigenin-enhanced chemiluminescence, quantitative PCR, Western blotting, and isometric myography. We demonstrated that both basal and NADPH-stimulated superoxide anion radical (O2•-) production was significantly higher in the arteries from young in comparison to adult rats. Importantly, pan-inhibitor of NADPH oxidase VAS2870 (10 μM) reduced NADPH-induced O2•- production in arteries of young rats. Saphenous arteries of both young and adult rats demonstrated high levels of Nox2 and Nox4 mRNAs, while Nox1 and Nox3 mRNAs were not detected. The protein contents of NOX2 and NOX4 were significantly higher in arterial tissue of young compared to adult animals. Moreover, VAS2870 (10 μM) had no effect on methoxamine-induced contractile responses of adult arteries but decreased them significantly in young arteries; such effect of VAS2870 persisted after removal of the endothelium. Finally, NOX2 inhibitor GSK2795039 (10 μM), but not NOX1/4 inhibitor GKT137831 (10 μM) weakened methoxamine-induced contractile responses of arteries from young rats. Thus, ROS produced by NOX2 have a pronounced contractile influence in saphenous artery smooth muscle cells of young, but not adult rats, which is associated with the increased vascular content of NOX2 protein at this age.

MANIPULATING MITOCHONDRIAL REACTIVE OXYGEN SPECIES ALTERS SURVIVAL IN UNEXPECTED WAYS IN A DROSOPHILA MODEL OF NEURODEGENERATION

Reactive oxygen species (ROS) are associated with aging and neurodegeneration, but the significance of this association remains obscure. Here, using a Drosophila model of age-related neurodegeneration, we probe this relationship in the pathologically relevant tissue, the brain, by quantifying three specific mitochondrial ROS and manipulating these redox species pharmacologically. Our goal is to ask whether pathology-associated changes in redox state are detrimental for survival, whether they may be beneficial responses, or whether they are simply covariates of pathology that do not alter viability. We find, surprisingly, that increasing mitochondrial H2O2 correlates with improved survival. We also find evidence that drugs that alter the mitochondrial glutathione redox potential modulate survival primarily through the compensatory effects they induce rather than through their direct effects on the final mitochondrial glutathione redox potential per se. We also find that the response to treatment with a redox-altering drug varies dramatically depending on the age at which the drug is administered, the duration of the treatment, and the genotype of the individual receiving the drug. These data have important implications for the design and interpretation of studies investigating the effect of redox state on health and disease as well as on efforts to modify the redox state to achieve therapeutic goals.

Root-derived long-distance signals trigger ABA synthesis and enhance drought resistance in Arabidopsis

Vascular plants have evolved intricate long-distance signaling mechanisms to cope with environmental stress, with reactive oxygen species (ROS) emerging as pivotal systemic signals in plant stress responses. However, the exact role of ROS as root-to-shoot signals in the drought response has not been determined. In this study, we reveal that compared with wild-type plants, ferric reductase defective 3 (frd3) mutants exhibit enhanced drought resistance concomitant with elevated NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3) transcript levels and abscisic acid (ABA) contents in leaves as well as increased hydrogen peroxide (H2O2) levels in roots and leaves. Grafting experiments distinctly illustrate that drought resistance can be conferred by the frd3 rootstock regardless of the scion genotype, indicating that long-distance signals originating from frd3 roots promote an increase in ABA levels in leaves. Intriguingly, the drought resistance conferred by the frd3 mutant rootstock is weakened by the CAT2-overexpressing scion, suggesting that H2O2 may be involved in long-distance signaling. Moreover, the results of comparative transcriptome and proteome analyses support the drought resistance phenotype of the frd3 mutant. Taken together, our findings substantiate the notion that frd3 root-derived long-distance signals trigger ABA synthesis in leaves and enhance drought resistance, providing new evidence for root-to-shoot long-distance signaling in the drought response of plants.

ROS Balance Autoregulating Core-Shell CeO2@ZIF-8/Au Nanoplatform for Wound Repair

Reactive oxygen species (ROS) plays important roles in living organisms. While ROS is a double-edged sword, which can eliminate drug-resistant bacteria, but excessive levels can cause oxidative damage to cells. A core-shell nanozyme, CeO2@ZIF-8/Au, has been crafted, spontaneously activating both ROS generating and scavenging functions, achieving the multi-faceted functions of eliminating bacteria, reducing inflammation, and promoting wound healing. The Au Nanoparticles (NPs) on the shell exhibit high-efficiency peroxidase-like activity, producing ROS to kill bacteria. Meanwhile, the encapsulation of CeO2 core within ZIF-8 provides a seal for temporarily limiting the superoxide dismutase and catalase-like activities of CeO2 nanoparticles. Subsequently, as the ZIF-8 structure decomposes in the acidic microenvironment, the CeO2 core is gradually released, exerting its ROS scavenging activity to eliminate excess ROS produced by the Au NPs. These two functions automatically and continuously regulate the balance of ROS levels, ultimately achieving the function of killing bacteria, reducing inflammation, and promoting wound healing. Such innovative ROS spontaneous regulators hold immense potential for revolutionizing the field of antibacterial agents and therapies.

A glutathione-independent DJ-1/Pfp1 domain containing glyoxalase III, OsDJ-1C, functions in abiotic stress adaptation in rice

MAIN CONCLUSION

Overexpression of OsDJ-1C in rice improves root architecture, photosynthesis, yield and abiotic stress tolerance through modulating methylglyoxal levels, antioxidant defense, and redox homeostasis. Exposure to abiotic stresses leads to elevated methylglyoxal (MG) levels in plants, impacting seed germination and root growth. In response, the activation of NADPH-dependent aldo-keto reductase and glutathione (GSH)-dependent glyoxalase enzymes helps to regulate MG levels and reduce its toxic effects. However, detoxification may not be carried out effectively due to the limitation of GSH and NADPH in plants under stress. Recently, a novel enzyme called glyoxalase III (GLY III) has been discovered which can detoxify MG in a single step without needing GSH. To understand the physiological importance of this pathway in rice, we overexpressed the gene encoding GLYIII enzyme (OsDJ-1C) in rice. It was observed that OsDJ-1C overexpression in rice regulated MG levels under stress conditions thus, linked well with plants' abiotic stress tolerance potential. The OsDJ-1C overexpression lines displayed better root architecture, improved photosynthesis, and reduced yield penalty compared to the WT plants under salinity, and drought stress conditions. These plants demonstrated an improved GSH/GSSG ratio, reduced level of reactive oxygen species, increased antioxidant capacity, and higher anti-glycation activity thereby indicating that the GLYIII mediated MG detoxification plays a significant role in plants' ability to reduce the impact of abiotic stress. Furthermore, these findings imply the potential of OsDJ-1C in crop improvement programs.

Grass carp peroxiredoxin 5 and 6-mediated autophagy inhibit grass carp reovirus replication and mitigate oxidative stress

Peroxiredoxins (Prxs) are a family of antioxidant enzymes crucial for shielding cells against oxidative damage from reactive oxygen species (ROS). In this study, we cloned and analyzed two grass carp peroxiredoxin genes, CiPrx5 and CiPrx6. These genes exhibited ubiquitous expression across all sampled tissues, with their expression levels significantly modulated upon exposure to grass carp reovirus (GCRV). CiPrx5 was localized in the mitochondria, while CiPrx6 was uniformly distributed in the whole cells. Transfection or transformation of CiPrx5 and CiPrx6 into fish cells or E. coli significantly enhanced host resistance to H2O2 and heavy metals, leading to increased cell viability and reduced cell apoptosis rates. Furthermore, purified recombinant CiPrx5 and CiPrx6 proteins effectively protected DNA against oxidative damage. Notably, overexpression of both peroxiredoxins in fish cells effectively inhibited GCRV replication, reduced intracellular ROS levels induced by GCRV infection and H2O2 treatment, and induced autophagy. Significantly, these functions of CiPrx5 and CiPrx6 in GCRV replication and ROS mitigation were abolished upon treatment with an autophagy inhibitor. In summation, our findings suggest that grass carp Prx5 and Prx6 promote autophagy to inhibit GCRV replication, decrease intracellular ROS, and provide protection against oxidative stress.

Interplay of mitochondria and diabetes: Unveiling novel therapeutic strategies

The interplay between mitochondrial function and diabetes has gained significant attention due to its crucial role in the pathogenesis and progression of the disease. Mitochondria, known as the cellular powerhouses, are essential for glucose metabolism. Dysfunction of these organelles has been implicated in the development of insulin resistance and beta-cell failure, both prominent features of diabetes. This comprehensive review explores the intricate mechanisms involved, including the generation of reactive oxygen species and the impact of mitochondrial DNA (mtDNA) mutations. Moreover, the review delves into emerging therapeutic strategies that specifically target mitochondria, such as mitochondria-targeted antioxidants, agents promoting mitochondrial biogenesis, and compounds modulating mitochondrial dynamics. The potential of these novel approaches is critically evaluated, taking into account their benefits and limitations, to provide a well-rounded perspective. Ultimately, this review emphasizes the importance of advancing our understanding of mitochondrial biology to revolutionize the treatment of diabetes.

Arabidopsis BECLIN1-induced autophagy mediates reprogramming in tapetal programmed cell death by altering the gross cellular homeostasis

In flowering plants, the tapetum degeneration in post-meiotic anther occurs through developmental programmed cell death (dPCD), which is one of the most critical and sensitive steps for the proper development of male gametophytes and fertility. Yet the pathways of dPCD, its regulation, and its interaction with autophagy remain elusive. Here, we report that high-level expression of Arabidopsis autophagy-related gene BECLIN1 (BECN1 or AtATG6) in the tobacco tapetum prior to their dPCD resulted in developmental defects. BECN1 induces severe autophagy and multiple cytoplasm-to-vacuole pathways, which alters tapetal cell reactive oxygen species (ROS)-homeostasis that represses the tapetal dPCD. The transcriptome analysis reveals that BECN1- expression caused major changes in the pathway, resulting in altered cellular homeostasis in the tapetal cell. Moreover, BECN1-mediated autophagy reprograms the execution of tapetal PCD by altering the expression of the key developmental PCD marker genes: SCPL48, CEP1, DMP4, BFN1, MC9, EXI1, and Bcl-2 member BAG5, and BAG6. This study demonstrates that BECN1-mediated autophagy is inhibitory to the dPCD of the tapetum, but the severity of autophagy leads to autophagic death in the later stages. The delayed and altered mode of tapetal degeneration resulted in male sterility.

The naringin/carboxymethyl chitosan/sodium hyaluronate/silk fibroin scaffold facilitates the healing of diabetic wounds by restoring the ROS-related dysfunction of vascularization and macrophage polarization

Chronic diabetic wounds remain a globally recognized clinical challenge, which occurs mainly due to the disturbances of wound microenvironmental induced by high concentrations of reactive oxygen species (ROS). Impairments in angiogenesis and inflammation in the wound microenvironment ultimately impede the normal healing process. Therefore, targeting macrophage and vascular endothelial cell dysfunction is a promising therapeutic strategy. In our study, we fabricated artificial composite scaffolds composed of naringin/carboxymethyl chitosan/sodium hyaluronate/silk fibroin (NG/CMCS/HA/SF) to promote wound healing. The NG/CMCS/HA/SF scaffold demonstrated favorable anti-inflammatory, anti-oxidative, and pro-angiogenic properties in both in vitro and in vivo experiments, effectively promoting the healing of diabetic wounds. The positive therapeutic effects observed indicate that the composite scaffolds have great potential in clinical wound healing applications.

Effects of ultraviolet radiation on cellular functions of the cyanobacterium Synechocystis sp. PCC 6803 and its recovery under photosynthetically active radiation

Cyanobacteria are photosynthetic organisms and challenged by large number of stresses, especially by ultraviolet radiation (UVR). UVR primarily impacts lipids, proteins, DNA, photosynthetic performance, which lowers the fitness and production of cyanobacteria. UVR has a catastrophic effect on cyanobacterial cells and eventually leads to cell death. UVR tolerance in the Synechocystis was poorly studied. Therefore, we irradiated Synechocystis sp. PCC 6803 to varying hours of photosynthetically active radiations (PAR), PAR + UV-A (PA), and PAR + UV-A + UV-B (PAB) for 48 h. To study the tolerance of Synechocystis sp. PCC 6803 against different UVR. The study shows that Chl a and total carotenoids content increased up to 36 h in PAR and PA, after 36 h a decrease was observed. PC increased up to 4-fold in 48 h of PA irradiation compared to 12 h. Maximum increase in ROS was observed under 48 h PAB i.e., 5.8-fold. Flowcytometry (FCM) based analysis shows that 25% of cells do not give fluorescence of Chl a and H2DCFH. In case of cell viability 10% cells were found to be non-viable in 48 h of PAB irradiance compared to 12 h. From the above study it was found that FCM-based approaches would provide a better understanding of the variations that occurred within the Synechocystis cells compared to fluorescence microscopy-based methods.

Refining antimicrobial photodynamic therapy: effect of charge distribution and central metal ion in fluorinated porphyrins on effective control of planktonic and biofilm bacterial forms

Antibiotic resistance represents a pressing global health challenge, now acknowledged as a critical concern within the framework of One Health. Photodynamic inactivation of microorganisms (PDI) offers an attractive, non-invasive approach known for its flexibility, independence from microbial resistance patterns, broad-spectrum efficacy, and minimal risk of inducing resistance. Various photosensitizers, including porphyrin derivatives have been explored for pathogen eradication. In this context, we present the synthesis, spectroscopic and photophysical characteristics as well as antimicrobial properties of a palladium(II)-porphyrin derivative (PdF2POH), along with its zinc(II)- and free-base counterparts (ZnF2POH and F2POH, respectively). Our findings reveal that the palladium(II)-porphyrin complex can be classified as an excellent generator of reactive oxygen species (ROS), encompassing both singlet oxygen (Φ△ = 0.93) and oxygen-centered radicals. The ability of photosensitizers to generate ROS was assessed using a variety of direct (luminescence measurements) and indirect techniques, including specific fluorescent probes both in solution and in microorganisms during the PDI procedure. We investigated the PDI efficacy of F2POH, ZnF2POH, and PdF2POH against both Gram-negative and Gram-positive bacteria. All tested compounds proved high activity against Gram-positive species, with PdF2POH exhibiting superior efficacy, leading to up to a 6-log reduction in S. aureus viability. Notably, PdF2POH-mediated PDI displayed remarkable effectiveness against S. aureus biofilm, a challenging target due to its complex structure and increased resistance to conventional treatments. Furthermore, our results show that PDI with PdF2POH is more selective for bacterial than for mammalian cells, particularly at lower light doses (up to 5 J/cm2 of blue light illumination). This enhanced efficacy of PdF2POH-mediated PDI as compared to ZnF2POH and F2POH can be attributed to more pronounced ROS generation by palladium derivative via both types of photochemical mechanisms (high yields of singlet oxygen generation as well as oxygen-centered radicals). Additionally, PDI proved effective in eliminating bacteria within S. aureus-infected human keratinocytes, inhibiting infection progression while preserving the viability and integrity of infected HaCaT cells. These findings underscore the potential of metalloporphyrins, particularly the Pd(II)-porphyrin complex, as promising photosensitizers for PDI in various bacterial infections, warranting further investigation in advanced infection models.

Polystyrene nanoplastics induce glycolipid metabolism disorder via NF-κB and MAPK signaling pathway in mice

Nanoplastics-induced developmental and reproductive toxicity, neurotoxicity and immunotoxicity are a focus of widespread attention. However, the effects of nanoplastics (NPs) on glycolipid metabolism and the precise underlying mechanisms are unclear at present. Here, we showed that oral administration of polystyrene nanoparticles (PS-NPs) disrupts glycolipid metabolism, with reactive oxygen species (ROS) identified as a potential key signaling molecule. After PS-NPs treatment, excessive production of ROS induced the inflammatory response and activated the antioxidant pathway through nuclear factor-erythroid factor 2-related factor 2. The activation of nuclear factor-κB (NFκB) signaling pathway induced the phosphorylation of the mitogen-activated protein kinases (MAPK) signaling pathway, which induced the activation of extracellular regulated kinases (ERK) and p38. Constitutive activation of the MAPK signaling proteins induced high continued phosphorylation of insulin receptor substrate-1, in turn, leading to decreased protein kinase B (Akt) activity, which weakened the sensitivity of liver cells to insulin signals and induced insulin resistance. In parallel, phosphorylation of Akt led to loss of control of FoXO1, a key gene of gluconeogenesis, activating transcription of glucose-6-phosphatase (G6PC) and phosphoenolpyruvate carboxykinase (PEPCK) in a manner dependent on PGC1α. Moreover, the activated ERK promoted lipid accumulation through ERK-PPARγ cascades. Therefore, sterol regulatory element-binding protein-1 and levels of its downstream lipogenic enzymes, ACC-1, were up-regulated. Upon treatment with the antioxidant resveratrol, PS-NPs-induced glucose and lipid metabolic disorders were improved by inhibiting ROS-induced activation of NFκB and MAPK signaling pathway in mice. Based on above, PS-NPs exposure disrupts glycolipid metabolism in mice, with ROS identified as a potential key signaling molecule.

Effect of photobiomodulation therapy on the morphology, intracellular calcium concentration, free radical generation, apoptosis and necrosis of human mesenchymal stem cells-an in vitro study

The aim of the study was to investigate the impact of multiwave locked system (MLS M1) emitting synchronized laser radiation at 2 wavelength simultaneous (λ = 808 nm, λ = 905 nm) on the mesenchymal stem cells (MSCs). Human MSCs were exposed to MLS M1 system laser radiation with the power density 195-318 mW/cm2 and doses of energy 3-20 J, in continuous wave emission (CW) or pulsed emission (PE). After irradiation exposure in doses of energy 3 J, 10 J (CW, ƒ = 1000 Hz), and 20 J (ƒ = 2000 Hz), increased proliferation of MSCs was observed. Significant reduction of Fluo-4 Direct™ Ca2+ indicator fluorescence over controls after CW and PE with 3 J, 10 J, and 20 J was noticed. A decrease in fluorescence intensity after the application of radiation with a frequency of 2000 Hz in doses of 3 J, 10 J, and 20 J was observed. In contrary, an increase in DCF fluorescence intensity after irradiation with laser radiation of 3 J, 10 J, and 20 J (CW, ƒ = 1000 Hz and ƒ = 2000 Hz) was also shown. Laser irradiation at a dose of 20 J, emitted at 1000 Hz and 2000 Hz, and 3 J emitted at a frequency of 2000 Hz caused a statistically significant loss of MSC viability. The applied photobiomodulation therapy induced a strong pro-apoptotic effect dependent on the laser irradiation exposure time, while the application of a sufficiently high-energy dose and frequency with a sufficiently long exposure time significantly increased intracellular calcium ion concentration and free radical production by MSCs.

α-lipoic acid modulates prostate cancer cell growth and bone cell differentiation

Prostate cancer (PCa) progression leads to bone modulation in approximately 70% of affected men. A nutraceutical, namely, α-lipoic acid (α-LA), is known for its potent anti-cancer properties towards various cancers and has been implicated in treating and promoting bone health. Our study aimed to explore the molecular mechanism behind the role of α-LA as therapeutics in preventing PCa and its associated bone modulation. Notably, α-LA treatment significantly reduced the cell viability, migration, and invasion of PCa cell lines in a dose-dependent manner. In addition, α-LA supplementation dramatically increased reactive oxygen species (ROS) levels and HIF-1α expression, which started the downstream molecular cascade and activated JNK/caspase-3 signaling pathway. Flow cytometry data revealed the arrest of the cell cycle in the S-phase, which has led to apoptosis of PCa cells. Furthermore, the results of ALP (Alkaline phosphatase) and TRAP (tartrate-resistant acid phosphatase) staining signifies that α-LA supplementation diminished the PCa-mediated differentiation of osteoblasts and osteoclasts, respectively, in the MC3T3-E1 and bone marrow macrophages (BMMs) cells. In summary, α-LA supplementation enhanced cellular apoptosis via increased ROS levels, HIF-1α expression, and JNK/caspase-3 signaling pathway in advanced human PCa cell lines. Also, the treatment of α-LA improved bone health by reducing PCa-mediated bone cell modulation.

Exploring the therapeutic potential of isoorientin in the treatment of osteoporosis: a study using network pharmacology and experimental validation

BACKGROUND

Isoorientin (ISO) is a glycosylated flavonoid with antitumor, anti-inflammatory, and antioxidant properties. However, its effects on bone metabolism remain largely unknown.

METHODS

In this study, we aimed to investigate the effects of ISO on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation in vitro and bone loss in post-ovariectomy (OVX) rats, as well as to elucidate the underlying mechanism. First, network pharmacology analysis indicated that MAPK1 and AKT1 may be potential therapeutic targets of ISO and that ISO has potential regulatory effects on the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathways, as well as oxidative stress. ISO was added to RAW264.7 cells stimulated by RANKL, and its effects on osteoclast differentiation were evaluated using tartrate-resistant acid phosphatase (TRAP) staining, TRAP activity measurement, and F-actin ring analysis. Reactive oxygen species (ROS) production in osteoclasts was detected using a ROS assay kit. The effects of ISO on RANKL-triggered molecular cascade response were further investigated by Western blotting, quantitative real-time polymerase chain reaction, and immunofluorescence staining. In addition, the therapeutic effects of ISO were evaluated in vivo.

RESULTS

ISO inhibited osteoclastogenesis in a time- and concentration-dependent manner. Mechanistically, ISO downregulated the expression of the main transcription factor for osteoclast differentiation by inhibiting MAPK and PI3K/AKT1 signaling pathways. Moreover, ISO exhibited protective effects in OVX-induced bone loss rats. This was consistent with the results derived from network pharmacology.

CONCLUSION

Our findings suggest a potential therapeutic utility of ISO in the management of osteoclast-associated bone diseases, including osteoporosis.

Synergistic bactericidal combinations between gentamicin and chitosan capped ZnO nanoparticles: A promising strategy for repositioning this first-line antibiotic

Gentamicin (GEN), a widely used broad-spectrum antibiotic, faces challenges amid the global emergency of antimicrobial resistance. This study aimed to explore the synergistic effects of zinc oxide nanoparticles (ZnO NPs) in combination with GEN on the bactericidal activity against various bacterial strains. Results showed ZnO NPs with MICs ranging from 0.002 to 1.5 μg/mL, while the precursor salt displayed a MIC range of 48.75-1560 μg/mL. Chitosan (CS)-capped ZnO NPs exhibited even lower MICs than their uncapped counterparts, with the CS-capped synthesized ZnO NPs demonstrating the lowest values. Minimal bactericidal concentrations (MBC) aligned with MIC trends. Combinations of CS-capped synthesized ZnO NPs and GEN proved highly effective, inhibiting bacterial growth at significantly lower concentrations than GEN or ZnO NPs alone. This phenomenon may be attributed to the conformation of CS on the ZnO NPs' surface, enhancing the positive particle surface charge. This possibly facilitates a more effective interaction between ZnO NPs and microorganisms, leading to increased accumulation of zinc and GEN within bacterial cells and an overproduction of reactive oxygen species (ROS). It's crucial to note that, while this study did not specifically involve resistant strains, its primary focus remains on enhancing the overall antimicrobial activity of gentamicin. The research aims to contribute to addressing the global challenge of antimicrobial resistance, recognizing the urgent need for effective strategies to combat this critical issue. The findings, particularly the observed synergy between ZnO NPs and GEN, hold significant implications for repositioning the first-line antibiotic GEN.

Synergistic effects of salt and ultraviolet radiation on the rice-field cyanobacterium Nostochopsis lobatus HKAR-21

Environmental variation has a significant impact on how organisms, including cyanobacteria, respond physiologically and biochemically. Salinity and ultraviolet radiation (UVR)-induced variations in the photopigments of the rice-field cyanobacterium Nostochopsis lobatus HKAR-21 and its photosynthetic performance was studied. We observed that excessive energy dissipation after UVR is mostly caused by Non-Photochemical Quenching (NPQ), whereas photochemical quenching is important for preventing photoinhibition. These findings suggest that ROS production may play an important role in the UVR-induced injury. To reduce ROS-induced oxidative stress, Nostochopsis lobatus HKAR-21 induces the effective antioxidant systems, which includes different antioxidant compounds like carotenoids and enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). The study indicates that Nostochopsis lobatus HKAR-21 exposed to photosynthetically active radiation + UV-A + UV-B (PAB) and PAB + NaCl (PABN) had significantly reduced photosynthetic efficiency. Furthermore, maximum ROS was detected in PAB exposed cyanobacterial cells. The induction of lipid peroxidation (LPO) has been investigated to evaluate the impact of UVR on the cyanobacterial membrane in addition to enzymatic defensive systems. The maximal LPO level was found in PABN treated cells. Based on the findings of this research, it was concluded that salinity and UVR had collegial effects on the major macromolecular components of the rice-field cyanobacterium Nostochopsis lobatus HKAR-21.

MRPL21 promotes HCC proliferation through TP53 mutation-induced apoptotic resistance

BACKGROUND AND AIMS

The specific mechanisms underlying the inhibition of hepatocellular carcinoma (HCC) proliferation and metastasis by mitochondrial apoptosis are not yet fully understood. However, it plays a vital role in suppressing HCC's ability to proliferate and spread. The involvement of MRPL21, a member within the family of mitochondrial ribosomal proteins (MRPs), is well-documented in both cellular apoptosis and energy metabolism. This study aims to explore and unravel the underlying mechanisms through which MRPL21 contributes to mitochondrial apoptosis and resistance against apoptosis in HCC.

METHODS

To evaluate the level of MRPL21 expression at the gene and protein expression levels, analysis was performed on human liver samples and blood using techniques for quantification. A knockdown plasmid targeting MRPL21 was constructed to investigate its impact on the growth and apoptosis of hepatocellular carcinoma (HCC). To evaluate the impact of MRPL21 knockdown on hepatocellular carcinoma (HCC) cell proliferation and apoptosis, various assays were performed including CCK-8 assays, flow cytometry analysis, detection of reactive oxygen species (ROS), and assessment of mitochondrial membrane potential (MMP). Furthermore, the role of MRPL21 in TP53 mutation was examined using Nutlin-3.

RESULTS

In HCC tissues and blood samples, an upregulation of MRPL21 expression was observed when compared to samples obtained from healthy individuals, and it is correlated with a poor prognosis for HCC. Silencing MRPL21 can effectively suppress Hep3B and HCCLM3 cells proliferation by modulating the mitochondrial membrane potential, it triggers the generation of reactive oxygen species (ROS), thereby leading to G0/G1 cell cycle arrest and initiation of early apoptosis. Furthermore, by inhibiting P53 activity, Nutlin-3 treatment can enhance MRPL21-deficiency-mediated apoptosis in Hep3B and HCCLM3 cells.

CONCLUSION

Through its influence on TP53 mutation, MRPL21 promotes HCC proliferation and progression while conferring resistance to apoptosis. These findings suggest that MRPL21 holds promise as a valuable biomarker for the treatment of HCC.

Empagliflozin prevents oxidative stress in human coronary artery endothelial cells via the NHE/PKC/NOX axis

BACKGROUND

Empagliflozin (EMPA) ameliorates reactive oxygen species (ROS) generation in human endothelial cells (ECs) exposed to 10 % stretch, but the underlying mechanisms are still unclear. Pathological stretch is supposed to stimulate protein kinase C (PKC) by increasing intracellular calcium (Ca2+), therefore activating nicotinamide adenine dinucleotide phosphate oxidase (NOX) and promoting ROS production in human ECs. We hypothesized that EMPA inhibits stretch-induced NOX activation and ROS generation through preventing PKC activation.

METHODS

Human coronary artery endothelial cells (HCAECs) were pre-incubated for 2 h before exposure to cyclic stretch (5 % or 10 %) with either vehicle, EMPA or the PKC inhibitor LY-333531 or PKC siRNA. PKC activity, NOX activity and ROS production were detected after 24 h. Furthermore, the Ca2+ chelator BAPTA-AM, NCX inhibitor ORM-10962 or NCX siRNA, sodium/potassium pump inhibitor ouabain and sodium hydrogen exchanger (NHE) inhibitor cariporide were applied to explore the involvement of the NHE/Na+/NCX/Ca2+ in the ROS inhibitory capacity of EMPA.

RESULTS

Compared to 5 % stretch, 10 % significantly increased PKC activity, which was reduced by EMPA and PKC inhibitor LY-333531. EMPA and LY-333531 showed a similar inhibitory capacity on NOX activity and ROS generation induced by 10 % stretch, which was not augmented by combined treatment with both drugs. PKC-β knockdown inhibits the NOX activation induced by Ca2+ and 10 % stretch. BAPTA, pharmacologic or genetic NCX inhibition and cariporide reduced Ca2+ in static HCAECs and prevented the activation of PKC and NOX in 10%-stretched cells. Ouabain increased ROS generation in cells exposed to 5 % stretch.

CONCLUSION

EMPA reduced NOX activity via attenuation of the NHE/Na+/NCX/Ca2+/PKC axis, leading to less ROS generation in HCAECs exposed to 10 % stretch.

Methyl β-Cyclodextrin-sperm-mediated gene editing (MBCD-SMGE): a simple and efficient method for targeted mutant mouse production

BACKGROUND

Generating targeted mutant mice is a crucial technology in biomedical research. This study focuses on optimizing the CRISPR/Cas9 system uptake into sperm cells using the methyl β-cyclodextrin-sperm-mediated gene transfer (MBCD-SMGT) technique to generate targeted mutant blastocysts and mice efficiently. Additionally, the present study elucidates the roles of cholesterol and reactive oxygen species (ROS) in the exogenous DNA uptake by sperm.

RESULTS

In this study, B6D2F1 mouse sperm were incubated in the c-TYH medium with different concentrations of MBCD (0, 0.75, 1, and 2 mM) in the presence of 20 ng/µl pCAG-eCas9-GFP-U6-gRNA (pgRNA-Cas9) for 30 min. Functional parameters, extracellular ROS, and the copy numbers of internalized plasmid per sperm cell were evaluated. Subsequently, in vitro fertilization (IVF) was performed and fertilization rate, early embryonic development, and transfection rate were assessed. Finally, our study investigated the potential of the MBCD-SMGT technique in combination with the CRISPR-Cas9 system, referred to as MBCD-SMGE (MBCD-sperm-mediated gene editing), for generating targeted mutant blastocysts and mice. Results indicated that cholesterol removal from the sperm membrane using MBCD resulted in a premature acrosomal reaction, an increase in extracellular ROS levels, and a dose-dependent influence on the copy numbers of the internalized plasmids per sperm cell. Moreover, the MBCD-SMGT technique led to a larger population of transfected motile sperm and a higher production rate of GFP-positive blastocysts. Additionally, the current study validated the targeted indel in blastocyst and mouse derived from MBCD-SMGE technique.

CONCLUSION

Overall, this study highlights the significant potential of the MBCD-SMGE technique for generating targeted mutant mice. It holds enormous promise for modeling human diseases and improving desirable traits in animals.

Amino acid derivative of probenecid potentiates apoptosis-inducing effects of vinblastine by increasing oxidative stress in a cancer cell-specific manner

Many chemotherapeutic drugs suffer from multidrug resistance (MDR). Efflux transporters, namely ATP-binding cassettes (ABCs), that pump the drugs out of the cancer cells comprise one major reason behind MDR. Therefore, ABC inhibitors have been under development for ages, but unfortunately, without clinical success. In the present study, an l-type amino acid transporter 1 (LAT1)-utilizing derivative of probenecid (PRB) was developed as a cancer cell-targeted efflux inhibitor for P-glycoprotein (P-gp), breast cancer resistant protein (BCRP) and/or several multidrug resistant proteins (MRPs), and its ability to increase vinblastine (VBL) cellular accumulation and apoptosis-inducing effects were explored. The novel amino acid derivative of PRB (2) increased the VBL exposure in triple-negative human breast cancer cells (MDA-MB-231) and human glioma cells (U-87MG) by 10-68 -times and 2-5-times, respectively, but not in estrogen receptor-positive human breast cancer cells (MCF-7). However, the combination therapy had greater cytotoxic effects in MCF-7 compared to MDA-MB-231 cells due to the increased oxidative stress recorded in MCF-7 cells. The metabolomic study also revealed that compound 2, together with VBL, decreased the transport of those amino acids essential for the biosynthesis of endogenous anti-oxidant glutathione (GSH). Moreover, the metabolic differences between the outcomes of the studied breast cancer cell lines were explained by the distinct expression profiles of solute carriers (SLCs) that can be concomitantly inhibited. Therefore, attacking several SLCs simultaneously to change the nutrient environment of cancer cells can serve as an adjuvant therapy to other chemotherapeutics, offering an alternative to ABC inhibitors.

Formononetin ameliorates cisplatin-induced hair cell death via activation of the PI3K/AKT-Nrf2 signaling pathway

Cisplatin (CDDP) stands as a highly effective chemotherapeutic agent; however, its ototoxicity remains a perplexing challenge in the field. Formononetin (FMNT), a potent flavonoid isolated from Astragalus membranaceus, displays a diverse range of promising pharmacological activities, encompassing antioxidant, anti-apoptotic, and anti-inflammatory effects. Nonetheless, the advantageous effects of FMNT on cisplatin-induced cochlear hair cell injury demand further investigation. This study aimed to assess the protective properties of FMNT against cisplatin-induced hair cell damage by conducting in vitro assays on explant-cultured cochlear hair cells. The findings revealed that FMNT exhibited a notable reduction in cisplatin-induced hair cell apoptosis. Also, FMNT effectively mitigated the accumulation of reactive oxygen species and mitochondrial damage in cochlear explants exposed to cisplatin, while also restoring the turnover of the reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio. Furthermore, our study demonstrated that FMNT protects hair cells against CDDP injury through the activation of the PI3K/AKT-Nrf2 signaling pathway. Consequently, formononetin emerges as a potential therapeutic agent for the treatment of cisplatin-induced ototoxicity.