Mitochondrial ROS Generation Research Articles

Synergistic neurological threat from Сu and wood smoke particulate matter

Trace metal Cu and carbonaceous airborn particulate matter (PM) are dangerous neuropollutants. Here, the ability of Cu2+ to modulate the neurotoxicity caused by water-suspended wood smoke PM preparations (SPs) and vice versa was examined using presynaptic rat cortex nerve terminals. Interaction of Cu2+ and SPs, changes of particle size and surface properties were shown in the presence of Cu2+ using microscopy, DLS, and IR spectroscopy. In nerve terminals, Cu2+ and SPs per se elevated the ambient levels of excitatory and inhibitory neurotransmitters L-[14C]glutamate and [3H]GABA, respectively. During combined application, Cu2+ significantly enhanced a SPs-induced increase in the ambient levels of both neurotransmitters, thereby demonstrating a cumulative synergistic effect and significant interference in the neurotoxic threat associated with Cu2+and SPs. In fluorimetric measurements, Cu2+ and SPs also demonstrated cumulative synergistic effects on the membrane potential, mitochondrial potential, synaptic vesicle acidification and ROS generation. Therefore, synergistic effects of Cu2+ and SPs on the most crucial presynaptic characteristics and neurohazard of multiple pollutants through excitatory/inhibitory imbalance, disruption of the membrane and mitochondrial potential, vesicle acidification and ROS generation were revealed. Increased expansion and burden of neuropathology may result from underestimation of synergistic interference of the neurotoxic effects of Cu2+ and carbonaceous smoke PM.

Betanin-encapsulated starch nanoparticles: synthesis and cytotoxic effect on colon cancer.

Colorectal cancer (CRC) is a common and life-threatening neoplastic disease that continues to pose a formidable challenge to global health. The present work was performed to evaluate the anticancer properties of betanin and betanin (BT) loaded starch nanoparticles (S-BT). The BT and S-BT were characterized by DLS, SEM, UV spectroscopy, XPS and FTIR. The cytotoxic effect was assessed by MTT and LDH assay. The apoptotic potential of BT and S-BT was assessed by DCFDA, Rh123, AO/EB and DAPI staining methods. Cell cycle arrest was depicted using flow cytometry. The antimetastatic potential of BT and S-BT was evaluated by wound healing assay. The S-BT showed a spherical morphology with a size of 175nm. The betanin contained SNPs were found to have strong encapsulation efficiency and favorable release profiles. Both BT and S-BT exhibited cytotoxicity in SW480 cells but S-BT displayed increased cytotoxicity when compared to BT alone. Loss of mitochondrial membrane potential, nuclear fragmentation, chromatin condensation and generation of ROS, all indicative of apoptotic mode of cell death, were revealed by fluorescence imaging. The cells were arrested in the G2M phase. Moreover, both BT and S-BT were able to inhibit the migratory potential of SW480 cells. Overall, our results indicated that both BT and S-BT were able to induce anticancer effects; and, S-BT was found to have increased therapeutic efficacy when compared to BT alone.

Plasminogen Activation Inhibitor-1 Promotes Resilience to Acute Oxidative Stress in Cerebral Arteries from Females.

Plasminogen activation inhibitor-1 (PAI-1) plays a central role in thrombus formation leading to stroke; however, the contributions of PAI-1 to cellular damage in response to reactive oxygen species which are elevated during reperfusion are unknown. Given that PAI-1 can limit apoptosis, we hypothesized that PAI increases the resilience of cerebral arteries to H2O2 (200 µM). Cell death, mitochondrial membrane potential, and mitochondrial ROS production were evaluated in pressurized mouse posterior cerebral arteries from males and females. The effects of pharmacological and genetic inhibition of PAI-1 signaling were evaluated with the inhibitor PAI-039 (10 µM) and PAI-1 knockout mice, respectively. During exposure to H2O2, PCAs from male mice lacking PAI-1 had reduced mitochondrial depolarization and smooth muscle cell death, and PAI-039 increased EC death. In contrast, mitochondrial depolarization and cell death were augmented in female PCAs. With no effect of PAI-1 inhibition on resting mitochondrial ROS production, vessels from female PAI-1 knockout mice had increased mitochondrial ROS generation during H2O2 exposure. During acute exposure to oxidative stress, protein ablation of PAI-1 enhances cell death in posterior cerebral arteries from females while limiting cell death in males. These findings provide important considerations for blood flow restoration during stroke treatment.

Activation of LONP1 by 84-B10 alleviates aristolochic acid nephropathy via re-establishing mitochondrial and peroxisomal homeostasis

Pharmaceutical formulations derived from Aristolochiaceae herbs, which contain aristolochic acids (AAs), are widely used for medicinal purposes. However, exposure to these plants and isolated AAs is linked to renal toxicity, known as AA nephropathy (AAN). Currently, the mechanisms underlying AAN are not fully understood, leading to unsatisfactory treatment strategies. In this study, we explored the protective role of 84-B10 (5-[[2-(4-methoxyphenoxy)-5-(trifluoromethyl) phenyl] amino]-5-oxo-3-phenylpentanoic acid) against AAN. RNA-seq analysis revealed that the mitochondrion and peroxisome were the most affected cellular components following 84-B10 treatment in AAN mice. Consistently, 84-B10 treatment preserved mitochondrial ultrastructure, restored mitochondrial respiration, enhanced the expression of key transporters (carnitine palmitoyltransferase 2) and enzymes (acyl-Coenzyme A dehydrogenase, medium chain) involved in mitochondrial fatty acid β-oxidation, and reduced mitochondrial ROS generation in both aristolochic acid I (AAI)-challenged mice kidneys and cultured proximal tubular epithelial cells. Additionally, 84-B10 treatment increased the expression of key transporters (ATP binding cassette subfamily D) and rate-limiting enzymes (acyl-CoA oxidase 1) involved in peroxisomal fatty acid β-oxidation and restored peroxisomal redox balance. Knocking down LONP1 expression diminished the protective effects of 84-B10 against AAN, suggesting LONP1-dependent protection. In conclusion, our study provides evidence that AAN is associated with significant disturbances in both mitochondrial and peroxisomal functions. The LONP1 activator 84-B10 demonstrates therapeutic potential against AAN, likely by maintaining homeostasis in both mitochondria and peroxisomes.

Diseleno-albumin, a native bio-inspired drug free therapeutic protein induces apoptosis in lung cancer cells through mitochondrial oxidation

Macromolecular therapeutic is the emerging concept in the fields of drug delivery and drug discovery. The present study reports the design and development of a serum albumin based macromolecular chemotherapeutic by conjugating bovine serum albumin (BSA) with 3,3′-diselenodipropionic acid (DSePA), a pharmacologically active organo-diselenide (R-Se-Se-R). The reaction conditions were optimised to achieve the controlled conjugation of BSA with DSePA without causing any significant alteration in its physico-chemical properties or secondary structure and crosslinking. The chemical characterisation of the reaction product through various spectroscopic techniques viz., FT-IR, Raman, XPS, AAS and MALDI-TOF-MS, established the conjugation of about ∼5 DSePA molecules per BSA molecule. The DSePA conjugated BSA (Se-Se-BSA) showed considerable stability in aqueous and lyophilized forms. The cytotoxicity studies by involving cell lines of cancerous and non-cancerous origins indicated that Se-Se-BSA selectively inhibited the proliferation of cancerous cells. The cellular uptake studies by physically labelling Se-Se-BSA with curcumin and following its intracellular fluorescence confirmed that uptake efficiency of Se-Se-BSA was almost similar to that of native BSA. Finally, studies on the mechanism of action of Se-Se-BSA in the A549 (lung adenocarcinoma) cells revealed that it induced mitochondrial ROS generation followed by mitochondrial dysfunction, activation of caspases and apoptosis. Together, these results demonstrate a bio-inspired approach of exploring diselenide (-Se-Se-) grafted serum albumin as the potential drug free therapeutic for anticancer application.

Insufficient FUNDC1-dependent mitophagy due to early environmental cadmium exposure triggers mitochondrial redox imbalance to aggravate diet-induced lipotoxicity

Cadmium (Cd) is a toxic contaminant widely spread in natural and industrial environments. Adolescent exposure to Cd increases risk for obesity-related morbidity in young adults including type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD). Despite this recognition, the direct impact of adolescent Cd exposure on the progression of MASLD later in life, and the mechanisms underlying these effects, remain unclear. Here, adolescent rats received control diet or diets containing 2 mg Cd2+/kg feed for 4 weeks, and then HFD containing 15% lard or control diet in young adult rats was selected for 6 weeks to clarify this issue. Data firstly showed that HFD-fed rats in young adulthood due to adolescent Cd exposure exhibited more severe MASLD, evidenced by increased liver damage, disordered serum and hepatic lipid levels, and activated NLRP3 inflammasome. Hepatic transcriptome analysis revealed the potential effects of mitochondrial dysfunction in aggravated MASLD due to Cd exposure. Verification data further confirmed that mitochondrial structure and function were targeted and disrupted during this process, shown by broken mitochondrial ridges, decreased mitochondrial membrane potential, imbalanced mitochondrial dynamic, insufficient ATP concentration, and enhanced mitochondrial ROS generation. However, mitophagy is inactively involved in clearance of damaged mitochondria induced by early Cd in HFD condition due to inhibited mitophagy receptor FUNDC1. In contrast, FUNDC1-dependent mitophagy activation prevents lipotoxicity aggravated by early Cd via suppressing mitochondrial ROS generation. Collectively, our data show that insufficient FUNDC1-dependent mitophagy can drive the transition from HFD-induced MASLD to MASH, and accordingly, these findings will provide a better understanding of potential mechanism of diet-induced metabolic diseases in the context of early environmental Cd exposure.

Acute Metabolic Stress Induces Lymphatic Dysfunction Through KATP Channel Activation.

Lymphatic dysfunction is an underlying component of multiple metabolic diseases, including diabetes, obesity, and metabolic syndrome. We investigated the roles of KATP channels in lymphatic contractile dysfunction in response to acute metabolic stress induced by inhibition of the mitochondrial electron transport chain. Ex vivo popliteal lymphatic vessels from mice were exposed to the electron transport chain inhibitors antimycin A and rotenone, or the oxidative phosphorylation inhibitor/protonophore, CCCP. Each inhibitor led to a significant reduction in the frequency of spontaneous lymphatic contractions and calculated pump flow, without a significant change in contraction amplitude. Contraction frequency was restored by the KATP channel inhibitor, glibenclamide. Lymphatic vessels from mice with global Kir6.1 deficiency or expressing a smooth muscle-specific dominant negative Kir6.1 channel were resistant to inhibition. Antimycin A inhibited the spontaneous action potentials generated in lymphatic muscle and this effect was reversed by glibenclamide, confirming the role of KATP channels. Antimycin A, but not rotenone or CCCP, increased dihydrorhodamine fluorescence in lymphatic muscle, indicating ROS production. Pretreatment with tiron or catalase prevented the effect of antimycin A on wild-type lymphatic vessels, consistent with its action being mediated by ROS. Our results support the conclusion that KATP channels in lymphatic muscle can be directly activated by reduced mitochondrial ATP production or ROS generation, consequent to acute metabolic stress, leading to contractile dysfunction through inhibition of the ionic pacemaker controlling spontaneous lymphatic contractions. We propose that a similar activation of KATP channels contributes to lymphatic dysfunction in metabolic disease.

Thymoquinone, artemisinin, and thymol attenuate proliferation of lung cancer cells as Sphingosine kinase 1 inhibitors

Sphingosine-1-phosphate (S1P) formed via catalytic actions of sphingosine kinase 1 (SphK1) behaves as a pro-survival substance and activates downstream target molecules associated with various pathologies, including initiation, inflammation, and progression of cancer. Here, we aimed to investigate the SphK1 inhibitory potentials of thymoquinone (TQ), Artemisinin (AR), and Thymol (TM) for the therapeutic management of lung cancer. We implemented docking, molecular dynamics (MD) simulations, enzyme inhibition assay, and fluorescence measurement studies to estimate binding affinity and SphK1 inhibitory potential of TQ, AR, and TM. We further investigated the anti-cancer potential of these compounds on non–small cell lung cancer (NSCLC) cell lines (H1299 and A549), followed by estimation of mitochondrial ROS, mitochondrial membrane potential depolarization, and cleavage of DNA by comet assay. Enzyme activity and fluorescence binding studies suggest that TQ, AR, and TM significantly inhibit the activity of SphK1 with IC50 values of 35.52 µM, 42.81 µM, and 53.68 µM, respectively, and have an excellent binding affinity. TQ shows cytotoxic effect and anti-proliferative potentials on H1299 and A549 with an IC50 value of 27.96 µM and 54.43 µM, respectively. Detection of mitochondrial ROS and mitochondrial membrane potential depolarization shows promising TQ-induced oxidative stress on H1299 and A549 cell lines. Comet assay shows promising TQ-induced oxidative DNA damage. In conclusion, TQ, AR, and TM act as potential inhibitors for SphK1, with a strong binding affinity. In addition, the cytotoxicity of TQ is linked to oxidative stress due to mitochondrial ROS generation. Overall, our study suggests that TQ is a promising inhibitor of SphK1 targeting lung cancer therapy.

Vaccarin Ameliorates Doxorubicin-Induced Cardiotoxicity via Inhibition of p38 MAPK Mediated Mitochondrial Dysfunction.

Doxorubicin is a frequently used chemotherapeutic agent for treating various malignancies. However, it leads to severe cardiotoxic side effects, such as heart failure, and elevates the risk of sudden cardiac death among cancer patients. While oxidative stress has been identified as the primary cause of doxorubicin-induced cardiotoxicity, therapeutic antioxidant approaches have yielded unsatisfactory outcomes. The aim of this study is to explore the therapeutic potential of vaccarin, an active flavonoid glycoside extracted from traditional Chinese herbal agent Semen Vaccariae, in doxorubicin-induced cardiotoxicity. We observed that vaccarin significantly ameliorates doxorubicin-induced heart dysfunction in mouse model and suppresses oxidative stress mediated cell apoptosis via specifically inhibiting the activation of p38 MAPK pathway. In vitro, we observed that vaccarin alleviates doxorubicin-induced mitochondrial membrane depolarization and ROS generation in H9c2 cell, but the p38 MAPK agonist anisomycin reverses these effects. Our findings provide a promising natural antioxidant to protect against DOX-induced cardiotoxicity.

Dopamine D2 Receptor Activation Blocks GluA2/ROS Positive Feedback Loop to Alienate Chronic-Migraine-Associated Pain Sensitization.

Chronic migraine is a disabling disorder without effective therapeutic medicine. AMPA receptors have been proven to be essential to pathological pain and headaches, but the related regulatory mechanisms in chronic migraine have not yet been explored. In this study, we found that the level of surface GluA2 was reduced in chronic migraine rats. Tat-GluR23Y (a GluA2 endocytosis inhibitor) reduced calcium inward flow and weakened synaptic structures, thus alleviating migraine-like pain sensitization. In addition, the inhibition of GluA2 endocytosis reduced the calcium influx and alleviated mitochondrial calcium overload and ROS generation in primary neurons. Furthermore, our results showed that ROS can induce allodynia and GluA2 endocytosis in rats, thus promoting migraine-like pain sensitization. In our previous study, the dopamine D2 receptor was identified as a potential target in the treatment of chronic migraine, and here we found that dopamine D2 receptor activation suppressed chronic-migraine-related pain sensitization through blocking the GluA2/ROS positive feedback loop in vivo and in vitro. Additionally, ligustrazine, a core component of ligusticum chuanxiong, was shown to target the dopamine D2 receptor, thereby alleviating ROS production and abnormal nociception in CM rats. This study provides valuable insight into the treatment of chronic migraine.

Deprivation of methionine inhibits osteosarcoma growth and metastasis via C1orf112-mediated regulation of mitochondrial functions

Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens patients’ lives. Thus, there is a dire clinical need to develop a novel therapy to tackle osteosarcoma metastasis. Methionine dependence is a special metabolic characteristic of most malignant tumor cells that may offer a target pathway for such therapy. Herein, we demonstrated that methionine deficiency restricted the growth and metastasis of cultured human osteosarcoma cells. A genetically engineered Salmonella, SGN1, capable of overexpressing an L-methioninase and hydrolyzing methionine led to significant reduction of methionine and S-adenosyl-methionine (SAM) specifically in tumor tissues, drastically restricted the growth and metastasis in subcutaneous xenograft, orthotopic, and tail vein-injected metastatic models, and prolonged the survival of the model animals. SGN1 also sharply suppressed the growth of patient-derived organoid and xenograft. Methionine restriction in the osteosarcoma cells initiated severe mitochondrial dysfunction, as evident in the dysregulated gene expression of respiratory chains, increased mitochondrial ROS generation, reduced ATP production, decreased basal and maximum respiration, and damaged mitochondrial membrane potential. Transcriptomic and molecular analysis revealed the reduction of C1orf112 expression as a primary mechanism underlies methionine deprivation-initiated suppression on the growth and metastasis as well as mitochondrial functions. Collectively, our findings unraveled a molecular linkage between methionine restriction, mitochondrial function, and osteosarcoma growth and metastasis. A pharmacological agent, such as SGN1, that can achieve tumor specific deprivation of methionine may represent a promising modality against the metastasis of osteosarcoma and potentially other types of sarcomas as well.

Integrating single-cell and multi-omic approaches reveals Euphorbiae Humifusae Herba-dependent mitochondrial dysfunction in non-small-cell lung cancer.

Euphorbiae Humifusae Herba (EHH) is a pivotal therapeutic agent with diverse pharmacological effects. However, a substantial gap exists in understanding its pharmacological properties and anti-tumour mechanisms. This study aimed to address this gap by exploring EHH's pharmacological properties, identifying NSCLC therapy-associated protein targets, and elucidating how EHH induces mitochondrial disruption in NSCLC cells, offering insights into novel NSCLC treatment strategies. String database was utilized to explore protein-protein interactions. Subsequently, single-cell analysis and multi-omics further unveiled the impact of EHH-targeted genes on the immune microenvironment of NSCLC, as well as their influence on immunotherapeutic responses. Finally, both invivo and invitro experiments elucidated the anti-tumour mechanisms of EHH, specifically through the assessment of mitochondrial ROS levels and alterations in mitochondrial membrane potential. EHH exerts its influence through engagement with a cluster of 10 genes, including the apoptotic gene CASP3. This regulatory impact on the immune milieu within NSCLC holds promise as an indicator for predicting responses to immunotherapy. Besides, EHH demonstrated the capability to induce mitochondrial ROS generation and perturbations in mitochondrial membrane potential in NSCLC cells, ultimately leading to mitochondrial dysfunction and consequent apoptosis of tumour cells. EHH induces mitochondrial disruption in NSCLC cells, leading to cell apoptosis to inhibit the progress of NSCLC.

Nr1h4 and Thrb ameliorate ER stress and provide protection in the MPTP mouse model of Parkinson's.

Elevated ER stress has been linked to the pathogenesis of several disease conditions including neurodegeneration. In this study, we have holistically determined the differential expression of all the nuclear receptors (NRs) in the presence of classical ER stress inducers. Activation of Nr1h4 and Thrb by their cognate ligands (GW4064 and T3) ameliorates the tunicamycin (TM)-induced expression of ER stress genes. A combination of both ligands is effective in mitigating cell death induced by TM. Further exploration of their protective effects in the Parkinson's disease (PD) model shows that they reduce MPP+-induced dissipation of mitochondrial membrane potential and ROS generation in an in vitro PD model in neuronal cells. Furthermore, the generation of an experimental murine PD model reveals that simultaneous treatment of GW4064 and T3 protects mice from ER stress, dopaminergic cell death, and functional deficits in the MPTP mouse model of PD. Thus, activation of Nr1h4 and Thrb by their respective ligands plays an indispensable role in ER stress amelioration and mounts protective effects in the MPTP mouse model of PD.

Isorhamnetin Alleviates Mitochondrial Injury in Severe Acute Pancreatitis via Modulation of KDM5B/HtrA2 Signaling Pathway.

Severe acute pancreatitis (SAP), a widespread inflammatory condition impacting the abdomen with a high mortality rate, poses challenges due to its unclear pathogenesis and the absence of effective treatment options. Isorhamnetin (ISO), a naturally occurring flavonoid, demonstrates robust antioxidant and anti-inflammatory properties intricately linked to the modulation of mitochondrial function. However, the specific protective impact of ISO on SAP remains to be fully elucidated. In this study, we demonstrated that ISO treatment significantly alleviated pancreatic damage and reduced serum lipase and amylase levels in the mouse model of SAP induced by sodium taurocholate (STC) or L-arginine. Utilizing an in vitro SAP cell model, we found that ISO co-administration markedly prevented STC-induced pancreatic acinar cell necrosis, primarily by inhibiting mitochondrial ROS generation, preserving ATP production, maintaining mitochondrial membrane potential, and preventing the oxidative damage and release of mitochondrial DNA. Mechanistically, our investigation identified that high-temperature requirement A2 (HtrA2) may play a central regulatory role in mediating the protective effect of ISO on mitochondrial dysfunction in STC-injured acinar cells. Furthermore, through an integrated approach involving bioinformatics analysis, molecular docking analysis, and experimental validation, we uncovered that ISO may directly impede the histone demethylation activity of KDM5B, leading to the restoration of pancreatic HtrA2 expression and thereby preserving mitochondrial function in pancreatic acinar cells following STC treatment. In conclusion, this study not only sheds new light on the intricate molecular complexities associated with mitochondrial dysfunction during the progression of SAP but also underscores the promising value of ISO as a natural therapeutic option for SAP.

Cassia fistula L. bark fraction modulated GSK3β/ p53 expression for mitochondrial mediated apoptosis in HeLa cells

In Ayurveda, Cassia fistula L. commonly known as Aragvadha (disease killer) is highly valuable medicinal plant. In the present study, hexane fraction (CaMH), chloroform fraction (CaMC), ethyl acetate fraction (CaME) and methanol fraction (CaMM) isolated from C. fistula bark were explored for their cytotoxic potential against cervical carcinoma (HeLa), breast carcinoma (MCF-7) and osteosarcoma (MG-63) cell lines using MTT assay. Our results unveiled that C. fistula bark fractions were selectively cytotoxic to carcinoma cells and among the tested fractions CaMC fraction had highest selectivity index (SI) with a value of 9.77 in HeLa cells. CaMC fraction actuated apoptosis in HeLa cells, as evident from chromatin condensation, DNA fragmentation, externalization of phosphatidylserine, altered mitochondrial membrane potential and ROS generation. Moreover, CaMC fraction upregulated the expression of GSK3β and p53 which modulated the Bax/ Bcl-2 ratio and initiated the release of cytochrome c from mitochondria. The expression of caspase 3/9 was also found to be upregulated which ultimately induced apoptosis. We also found that CaMC induced cell cycle arrest at G0/G1 phase and significantly inhibited the migration in HeLa cells. GC–MS analysis showed Oleic Acid, Piperine, Isopiperine and Tris(2,4-di‑tert-butylphenyl) phosphate as major constituents which could be attributed to anticancer activity of CaMC. The present study affirms the potential of CaMC fraction in modulating the aberrant signaling pathway for the induction of apoptosis in HeLa cells.

Therapeutic efficacy and anti-inflammatory mechanism of baicalein on endometriosis progression in patient-derived cell line and mouse model

BackgroundBaicalein is a flavonoid extracted from the roots of Scutellaria baicalensis G. that has anti-inflammatory and antitumor effects. However, therapeutic mechanisms of baicalein in patients with endometriosis in vivo have yet to be elucidated. As a chronic inflammatory gynecological disease, endometriosis causes pain and infertility, and has no complete treatment to date. Current treatment strategies cause several side effects and have high recurrence rates. PurposeThis study aimed to identify the in vivo therapeutic effects of baicalein on endometriosis and verify the action mechanisms of baicalein, focusing on regulating inflammation. MethodsIn this study, an autologous transplant mouse model and patient-derived immortalized human ovarian endometriotic stromal cells (ihOESCs) were used to investigate the therapeutic activities of baicalein. The mouse model was administered with 40 mg/kg baicalein by oral gavage for 4 weeks, and the treatment outcomes of baicalein-treated mice were compared with vehicle- and dienogest-treated groups. ihOESCs were treated with 0–5 μg/ml baicalein for in vitro studies. ResultsBaicalein significantly alleviated the progression of endometriosis in mouse models. Baicalein reduced the expression of proinflammatory cytokines in endometriotic lesions and ihOESCs, and cytokine expression and T cell proportions in mouse spleen. in vitro results showed that baicalein increased mitochondrial calcium flux and induced mitochondrial depolarization and ROS generation in ihOESCs. Ultimately, baicalein inactivated the MAPK/PI3K signaling and induced cell death in ihOESCs. ConclusionIn conclusion, baicalein effectively attenuated the progression of endometriosis through its anti-inflammatory activities. Baicalein can be an alternative or supplemental treatment for endometriosis to ameliorate the side effects of hormonal therapy.

Cell-intrinsic C5a synergizes with Dectin-1 in macrophages to mediate fungal killing

The complement factor C5a is a core effector product of complement activation. C5a, acting through its receptors C5aR1 and C5aR2, exerts pleiotropic immunomodulatory functions in myeloid cells, which is vital for host defense against pathogens. Pattern-recognition receptors (PRRs) are similarly expressed by immune cells as detectors of pathogen-associated molecular patterns. Although there is evidence of cross talk between complement and PRR signaling pathways, knowledge of the full potential for C5a-PRR interaction is limited. In this study, we comprehensively investigated how C5a signaling through C5a receptors can modulate diverse PRR-mediated cytokine responses in human primary monocyte-derived macrophages and observed a powerful, concentration-dependent bidirectional effect of C5a on PRR activities. Unexpectedly, C5a synergized with Dectin-1, Mincle, and STING in macrophages to a much greater extent than TLRs. Notably, we also identified that selective Dectin-1 activation using depleted zymosan triggered macrophages to generate cell-intrinsic C5a, which acted on intracellular and cell surface C5aR1, to help sustain mitochondrial ROS generation, up-regulate TNFα production, and enhance fungal killing. This study adds further evidence to the holistic functions of C5a as a central immunomodulator and important orchestrator of pathogen sensing and killing by phagocytes.

Intracellular delivery of piezotronic-dominated nanocatalysis to mimic mitochondrial ROS generation for powering macrophage immunotherapy

Macrophages are the first line of host defense against bacterial infections and mitochondrial reactive oxygen species (mROS) plays an important role in the bactericidal innate response of macrophages. In this work, we propose the concept of engineering macrophages with artificial mROS generation ability to combat bacterial infection, which is enabled by metal phenolic network-mediated lysosomal escape of piezocatalytic nanoparticles (piezoNPs) and piezotronic effect-enhanced intracellular piezocatalysis. By harvesting ultrasound energy, the engineered macrophages can demonstrate pro-inflammatory phenotype, potent phagocytosis and strong bactericidal activity against Staphylococcus aureus (S. aureus). By in situ engineering macrophages at the infection site with targeting ligand-modified piezoNPs, the treatment of S. aureus abscess is further demonstrated. This study reveals the potential of intracellular piezotronic nanocatalysis in enhancing innate immune response of macrophages, providing a non-invasive modulation of macrophages-mediated immunotherapy.

Impact of the hypoxic microenvironment on spermatogonial stem cells in culture.

The stem cell niche plays a crucial role in the decision to either self-renew or differentiate. Recent observations lead to the hypothesis that O2 supply by blood and local O2 tension could be key components of the testicular niche of spermatogonial stem cells (SSCs). In this study, we investigated the impact of different hypoxic conditions (3.5%, 1%, and 0.1% O2 tension) on murine and human SSCs in culture. We observed a deleterious effect of severe hypoxia (1% O2 and 0.1% O2) on the capacity of murine SSCs to form germ cell clusters when plated at low density. Severe effects on SSCs proliferation occur at an O2 tension ≤1% and hypoxia was shown to induce a slight differentiation bias under 1% and 0.1% O2 conditions. Exposure to hypoxia did not appear to change the mitochondrial mass and the potential of membrane of mitochondria in SSCs, but induced the generation of mitochondrial ROS at 3.5% and 1% O2. In 3.5% O2 conditions, the capacity of SSCs to form colonies was maintained at the level of 21% O2 at low cell density, but it was impossible to amplify and maintain stem cell number in high cell density culture. In addition, we observed that 3.5% hypoxia did not improve the maintenance and propagation of human SSCs. Finally, our data tend to show that the transcription factors HIF-1α and HIF-2α are not involved in the SSCs cell autonomous response to hypoxia.

The Tumor Suppressor SOCS1 Diminishes Tolerance to Oxidative Stress in Hepatocellular Carcinoma.

SOCS1 is a tumor suppressor in hepatocellular carcinoma (HCC). Recently, we showed that a loss of SOCS1 in hepatocytes promotes NRF2 activation. Here, we investigated how SOCS1 expression in HCC cells affected oxidative stress response and modulated the cellular proteome. Murine Hepa1-6 cells expressing SOCS1 (Hepa-SOCS1) or control vector (Hepa-Vector) were treated with cisplatin or tert-butyl hydroperoxide (t-BHP). The induction of NRF2 and its target genes, oxidative stress, lipid peroxidation, cell survival and cellular proteome profiles were evaluated. NRF2 induction was significantly reduced in Hepa-SOCS1 cells. The gene and protein expression of NRF2 targets were differentially induced in Hepa-Vector cells but markedly suppressed in Hepa-SOCS1 cells. Hepa-SOCS1 cells displayed an increased induction of reactive oxygen species but reduced lipid peroxidation. Nonetheless, Hepa-SOCS1 cells treated with cisplatin or t-BHP showed reduced survival. GCLC, poorly induced in Hepa-SOCS1 cells, showed a strong positive correlation with NFE2L2 and an inverse correlation with SOCS1 in the TCGA-LIHC transcriptomic data. A proteomic analysis of Hepa-Vector and Hepa-SOCS1 cells revealed that SOCS1 differentially modulated many proteins involved in diverse molecular pathways, including mitochondrial ROS generation and ROS detoxification, through peroxiredoxin and thioredoxin systems. Our findings indicate that maintaining sensitivity to oxidative stress is an important tumor suppression mechanism of SOCS1 in HCC.