Nrf-2 overexpression in mesenchymal stem cells reduces oxidative stress-induced apoptosis and cytotoxicity

Repeated Sulforaphane Treatment Reverses Depressive-like Behavior and Exerts Antioxidant Effects in the Olfactory Bulbectomy Model in Mice

Growing evidence suggests that activators of nuclear factor erythroid-derived 2-like 2 (Nrf2), such as sulforaphane, may represent promising novel pharmacological targets for conditions related to oxidative stress, including depressive disorder. Therefore, we conducted a study to explore the behavioral and biochemical effects of repeated (14 days) sulforaphane (SFN) treatment in the olfactory bulbectomy (OB) animal model of depression. An open field test (OFT), splash test (ST), and spontaneous locomotor activity test (LA) were used to assess changes in depressive-like behavior and the potential antidepressant-like activity of SFN. The OB model induced hyperactivity in mice during the OFT and LA as well as a temporary loss of self-care and motivation in the ST. The repeated administration of SFN (10 mg/kg) effectively reversed these behavioral changes in OB mice across all tests. Additionally, a biochemical analysis revealed that SFN (10 mg/kg) increased the total antioxidant capacity in the frontal cortex and serum of the OB model. Furthermore, SFN (10 mg/kg) significantly enhanced superoxide dismutase activity in the serum of OB mice. Overall, the present study is the first to demonstrate the antidepressant-like effects of repeated SFN (10 mg/kg) treatment in the OB model and indicates that these benefits may be linked to improved oxidative status.

Regulation of the Nrf2/HO-1 axis by mesenchymal stem cells-derived extracellular vesicles: implications for disease treatment

This comprehensive review inspects the therapeutic potential of mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) across multiple organ systems. Examining their impact on the integumentary, respiratory, cardiovascular, urinary, and skeletal systems, the study highlights the versatility of MSC-EVs in addressing diverse medical conditions. Key pathways, such as Nrf2/HO-1, consistently emerge as central mediators of their antioxidative and anti-inflammatory effects. From expediting diabetic wound healing to mitigating oxidative stress-induced skin injuries, alleviating acute lung injuries, and even offering solutions for conditions like myocardial infarction and renal ischemia-reperfusion injury, MSC-EVs demonstrate promising therapeutic efficacy. Their adaptability to different administration routes and identifying specific factors opens avenues for innovative regenerative strategies. This review positions MSC-EVs as promising candidates for future clinical applications, providing a comprehensive overview of their potential impact on regenerative medicine.

USP8 prevents aberrant NF-κB and Nrf2 activation by counteracting ubiquitin signals from endosomes

K63-linked ubiquitin chains attached to plasma membrane proteins serve as tags for endocytosis and endosome-to-lysosome sorting. USP8 is an essential deubiquitinase for the maintenance of endosomal functions. Prolonged depletion of USP8 leads to cell death, but the major effects on cellular signaling pathways are poorly understood. Here, we show that USP8 depletion causes aberrant accumulation of K63-linked ubiquitin chains on endosomes and induces immune and stress responses. Upon USP8 depletion, two different decoders for K63-linked ubiquitin chains, TAB2/3 and p62, were recruited to endosomes and activated the TAK1-NF-κB and Keap1-Nrf2 pathways, respectively. Oxidative stress, an environmental stimulus that potentially suppresses USP8 activity, induced accumulation of K63-linked ubiquitin chains on endosomes, recruitment of TAB2, and expression of the inflammatory cytokine. The results demonstrate that USP8 is a gatekeeper of misdirected ubiquitin signals and inhibits immune and stress response pathways by removing K63-linked ubiquitin chains from endosomes.

Valproic acid and/or rapamycin preconditioning protects hair follicle stem cells from oxygen glucose serum deprivation-induced oxidative injury via activating Nrf2 pathway

Among leading causes of the ischemic stroke pathogenesis, oxidative stress strongly declines rate of stem cell engraftment at the injury site, and disables stem cell-based therapy as a key treatment for ischemia stroke. To overcome this therapeutic limitation, preconditioning has been represented a possible approach to augment the adaptation and viability of stem cells to oxidative stress. Here, we illustrated protective impacts of valproic acid (VPA) and/or rapamycin (RAPA) preconditioning unto oxygen glucose and serum deprivation (OGSD)-stimulated cell damage in hair follicle-derived stem cells (HFSCs) and surveyed the plausible inducement mechanisms. OGSD, as an in vitro cell injury model, was established and HFSCs viability was observed using MTT assay after VPA, RAPA, and VPA-RAPA preconditioning under OGSD. ROS and MDA production was assessed to reflect oxidative stress. Real-time PCR and western blotting were employed to investigate Nrf2 expression. The activity of Nrf2-related antioxidant enzymes including NQO1, GPx and GSH level were examined. VEGF and BDNF mRNA expression levels were analyzed. Our results showed that VPA and/or RAPA preconditioning ameliorated OGSD-induced decline in HFSCs viability. In addition, they considerably prohibited ROS and MDA generation in the OGSD-treated HFSCs. Furthermore, VPA and/or RAPA preconditioning stimulated Nrf2 nuclear repositioning and NQO1 and GPx activity and GSH amount, as well as expression of paracrine factors VEGF and BDNF in OGSD-treated HFSCs. Thus, the protective effects afforded by VPA and/or RAPA preconditioning, which involved Nrf2-modulated oxidant stress and regulation of VEGF and BDNF expression, display a simple strategy to augment cell-transplantation efficiency for ischemic stroke.

Fucoxanthin diminishes oxidative stress damage in human placenta-derived mesenchymal stem cells through the PI3K/Akt/Nrf-2 pathway

Placenta-derived mesenchymal stem cells (PL-MSCs) have therapeutic potential in various clinical contexts due to their regenerative and immunomodulatory properties. However, with increasing age or extensive in vitro culture, their viability and function are gradually lost, thus restricting their therapeutic application. The primary cause of this deterioration is oxidative injury from free radicals. Therefore, enhancing cell viability and restoring cellular repair mechanisms of PL-MSCs in an oxidative stress environment are crucial in this context. Fucoxanthin, a carotenoid derived from brown seaweed, demonstrates antioxidant activity by increasing the production of antioxidant enzymes and lowering the levels of reactive oxygen species (ROS). This study aimed to determine whether fucoxanthin protects PL-MSCs from hydrogen peroxide (H2O2)-induced oxidative stress. After characterization, PL-MSCs were co-treated with fucoxanthin and H2O2 for 24 h (co-treatment) or pre-treated with fucoxanthin for 24 h followed by H2O2 for 24 h (pre-treatment). The effects of fucoxanthin on cell viability and proliferation were examined using an MTT assay. The expression of antioxidant enzymes, PI3K/Akt/Nrf-2 and intracellular ROS production were investigated in fucoxanthin-treated PL-MSCs compared to the untreated group. The gene expression and involvement of specific pathways in the cytoprotective effect of fucoxanthin were investigated by high-throughput NanoString nCounter analysis. The results demonstrated that co-treatment and pre-treatment with fucoxanthin restored the viability and proliferative capacity of PL-MSCs. Fucoxanthin treatment increased the expression of antioxidant enzymes in PL-MSCs cultured under oxidative stress conditions and decreased intracellular ROS accumulation. Markedly, fucoxanthin treatment could restore PI3K/Akt/Nrf-2 expression in H2O2-treated PL-MSCs. High-throughput analysis revealed up-regulation of genes involved in cell survival pathways, including cell cycle and proliferation, DNA damage repair pathways, and down-regulation of genes in apoptosis and autophagy pathways. This study demonstrated that fucoxanthin protects and rescues PL-MSCs from oxidative stress damage through the PI3K/Akt/Nrf-2 pathway. Our data provide the supporting evidence for the use of fucoxanthin as an antioxidant cytoprotective agent to improve the viability and proliferation capacity of PL-MSCs both in vitro and in vivo required to increase the effectiveness of MSC expansion for therapeutic applications.

CXCL10 and Nrf2-upregulated mesenchymal stem cells reinvigorate T lymphocytes for combating glioblastoma

BACKGROUND

Lack of tumor-infiltrating T lymphocytes and concurrent T-cell dysfunction have been identified as major contributors to glioblastoma (GBM) immunotherapy resistance. Upregulating CXCL10 in the tumor microenvironment (TME) is a promising immunotherapeutic approach that potentially increases tumor-infiltrating T cells and boosts T-cell activity but is lacking effective delivery methods.

METHODS

In this study, mesenchymal stem cells (MSCs) were transduced with a recombinant lentivirus encoding Cxcl10, Nrf2 (an anti-apoptosis gene), and a ferritin heavy chain (Fth) reporter gene in order to increase their CXCL10 secretion, TME survival, and MRI visibility. Using FTH-MRI guidance, these cells were injected into the tumor periphery of orthotopic GL261 and CT2A GBMs in mice. Combination therapy consisting of CXCL10-Nrf2-FTH-MSC transplantation together with immune checkpoint blockade (ICB) was also performed for CT2A GBMs. Thereafter, in vivo and serial MRI, survival analysis, and histology examinations were conducted to assess the treatments' efficacy and mechanism.

RESULTS

CXCL10-Nrf2-FTH-MSCs exhibit enhanced T lymphocyte recruitment, oxidative stress tolerance, and iron accumulation. Under in vivo FTH-MRI guidance and monitoring, peritumoral transplantation of CXCL10-Nrf2-FTH-MSCs remarkably inhibited orthotopic GL261 and CT2A tumor growth in C57BL6 mice and prolonged animal survival. While ICB alone demonstrated no therapeutic impact, CXCL10-Nrf2-FTH-MSC transplantation combined with ICB demonstrated an enhanced anticancer effect for CT2A GBMs compared with transplanting it alone. Histology revealed that peritumorally injected CXCL10-Nrf2-FTH-MSCs survived longer in the TME, increased CXCL10 production, and ultimately remodeled the TME by increasing CD8+ T cells, interferon-γ+ cytotoxic T lymphocytes (CTLs), GzmB+ CTLs, and Th1 cells while reducing regulatory T cells (Tregs), exhausted CD8+ and exhausted CD4+ T cells.

CONCLUSIONS

MRI-guided peritumoral administration of CXCL10 and Nrf2-overexpressed MSCs can significantly limit GBM growth by revitalizing T lymphocytes within TME. The combination application of CXCL10-Nrf2-FTH-MSC transplantation and ICB therapy presents a potentially effective approach to treating GBM.

Revolutionizing bone regeneration: advanced biomaterials for healing compromised bone defects

In this review, we explore the application of novel biomaterial-based therapies specifically targeted towards craniofacial bone defects. The repair and regeneration of critical sized bone defects in the craniofacial region requires the use of bioactive materials to stabilize and expedite the healing process. However, the existing clinical approaches face challenges in effectively treating complex craniofacial bone defects, including issues such as oxidative stress, inflammation, and soft tissue loss. Given that a significant portion of individuals affected by traumatic bone defects in the craniofacial area belong to the aging population, there is an urgent need for innovative biomaterials to address the declining rate of new bone formation associated with age-related changes in the skeletal system. This article emphasizes the importance of semiconductor industry-derived materials as a potential solution to combat oxidative stress and address the challenges associated with aging bone. Furthermore, we discuss various material and autologous treatment approaches, as well as in vitro and in vivo models used to investigate new therapeutic strategies in the context of craniofacial bone repair. By focusing on these aspects, we aim to shed light on the potential of advanced biomaterials to overcome the limitations of current treatments and pave the way for more effective and efficient therapeutic interventions for craniofacial bone defects.

Preconditioning adipose-derived mesenchymal stem cells with dimethyl fumarate promotes their therapeutic efficacy in the brain tissues of rats with Alzheimer's disease

AIM

Transplantation of mesenchymal stem cell (MSC) has been suggested to be a promising method for treating neurodegenerative conditions, including Alzheimer's disease (AD). However, the poor survival rate of transplanted MSCs has limited their therapeutic application. This study aimed to evaluate whether preconditioning MSCs with dimethyl fumarate (DMF), a Nrf2 inducer, could enhance MSC therapeutic efficacy in an amyloid-β (Aβ_1-42)-induced AD rat model.

METHODS

The survival and antioxidant capacity of MSCs treated with DMF were assessed in vitro. Aβ_1-42 intrahippocampal injection was used to create a rat model of AD. Following the transplantation of MSCs preconditioned with DMF and using the Morris blue maze test, spatial learning and memory were assessed. Using RT-qPCR, we evaluated the gene expression related to apoptosis and neurotrophins in the hippocampus region.

RESULTS

Treatment with DMF enhanced cell survival and Nrf2 protein expression in MSCs in vitro. Preconditioning with DMF also enhanced the efficacy of transplanted MSCs in rescuing learning and spatial memory deficits in Aβ-AD rats. Besides, DMF preconditioning enhanced the neuroprotective effect of transplanted MSCs in the hippocampus of rats treated with Aβ_1-42 by decreasing the expression of apoptotic markers (Bax, caspase 3, and cytochrome c), and elevating the expression of the anti-apoptotic marker Bcl2 and neurotrophins, including BDNF and NGF.

CONCLUSION

Preconditioning MSCs with DMF boosted the therapeutic efficacy of these cells; therefore, it could serve as a targeted strategy for increasing the therapeutic efficacy of MSCs in treating neurodegenerative disorders, including AD.

Association of nanoparticles and Nrf2 with various oxidative stress-mediated diseases

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regultes the cellular antioxidant defense system at the posttranscriptional level. During oxidative stress, Nrf2 is released from its negative regulator Kelch-like ECH-associated protein 1 (Keap1) and binds to antioxidant response element (ARE) to transcribe antioxidative metabolizing/detoxifying genes. Various transcription factors like aryl hydrocarbon receptor (AhR) and nuclear factor kappa light chain enhancer of activated B cells (NF-kB) and epigenetic modification including DNA methylation and histone methylation might also regulate the expression of Nrf2. Despite its protective role, Keap1/Nrf2/ARE signaling is considered as a pharmacological target due to its involvement in various pathophysiological conditions such as diabetes, cardiovascular disease, cancer, neurodegenerative diseases, hepatotoxicity and kidney disorders. Recently, nanomaterials have received a lot of attention due to their unique physiochemical properties and are also used in various biological applications, for example, biosensors, drug delivery systems, cancer therapy, etc. In this review, we will be discussing the functions of nanoparticles and Nrf2 as a combined therapy or sensitizing agent and their significance in various diseases such as diabetes, cancer and oxidative stress-mediated diseases.

Ferroptosis As Ultimate Target of Cancer Therapy

Significance: The significance of ferroptosis in cancer therapeutics has now been unveiled. Specific ferroptosis inducers are expected as a promising strategy for cancer treatment, especially in cancers with epithelial mesenchymal transition and possibly in cancers with activated Hippo signaling pathways, both of which cause resistance to traditional chemotherapy but tend to show ferroptosis susceptibility. Recent Advances: Ferroptosis is a new form of regulated non-apoptotic cell death, which is characterized by iron-dependent lipid peroxidation, leading eventually to plasma membrane rupture. Its core mechanisms have been elucidated, consisting of a driving force as catalytic Fe(II)-dependent Fenton reaction and an incorporation of polyunsaturated fatty acids to membrane phospholipids via peroxisome-dependent and -independent pathways, and suppressing factors as prevention of lipid peroxidation with glutathione peroxidase 4 and direct membrane repair via coenzyme Q10 and ESCRT-III pathways. Critical Issues: Developments of ferroptosis inducers are in progress by nanotechnology-based drugs or by innovative engineering devices. Especially, low-temperature (non-thermal) plasma is a novel technology at the preclinical stage. The exposure can induce ferroptosis selectively in cancer cells rich in catalytic Fe(II). Future Directions: We also summarize and discuss the recently uncovered responsible molecular mechanisms in association with iron metabolism, ferroptosis and cancer therapeutics. Targeting ferroptosis in addition to the current therapeutic modalities would be important to cure advanced-stage cancer.

Incorporation of paclitaxel in mesenchymal stem cells using nanoengineering upregulates antioxidant response, CXCR4 expression and enhances tumor homing

Engineered mesenchymal stem cells (MSCs) have been investigated extensively for gene delivery and, more recently, for targeted small molecule delivery. While preclinical studies demonstrate the potential of MSCs for targeted delivery, clinical studies suggest that tumor homing of native MSCs may be inefficient. We report here a surprising finding that loading MSCs with the anticancer drug paclitaxel (PTX) by nanoengineering results in significantly improved tumor homing compared to naïve MSCs. Loading PTX in MSCs results in increased levels of mitochondrial reactive oxygen species (ROS). In response to this oxidative stress, MSCs upregulate two important set of proteins. First were critical antioxidant proteins, most importantly nuclear factor erythroid 2-like 2 (Nrf2), the master regulator of antioxidant responses; upregulation of antioxidant proteins may explain how MSCs protect themselves from drug-induced oxidative stress. The second was CXCR4, a direct target of Nrf2 and a key mediator of tumor homing; upregulation of CXCR4 suggested a mechanism that may underlie the improved tumor homing of nanoengineered MSCs. In addition to demonstrating the potential mechanism of improved tumor targeting of nanoengineered MSCs, our studies reveal that MSCs utilize a novel mechanism of resistance against drug-induced oxidative stress and cell death, explaining how MSCs can deliver therapeutic concentrations of cytotoxic payload while maintaining their viability.

The role of Nrf2 in periodontal disease by regulating lipid peroxidation, inflammation and apoptosis

Nuclear factor E2-related factor 2(Nrf2) is a transcription factor that mainly regulates oxidative stress in the body. It initiates the expression of several downstream antioxidants, anti-inflammatory proteins and detoxification enzymes through the Kelch-like ECH-associating protein 1 (Keap1) -nuclear factor E2-related factor 2(Nrf2) -antioxidant response element (ARE) signaling pathway. Its anti-apoptosis, anti-oxidative stress and anti-inflammatory effects have gradually become the focus of periodontal disease research in recent years. In this paper, the structure and function of Nrf2 pathway and its mechanism of action in the treatment of periodontitis in recent years were analyzed and summarized, so as to further clarify the relationship between Nrf2 pathway and oxidative stress in the occurrence and development of periodontitis, and to provide ideas for the development of new treatment drugs targeting Nrf2 pathway.

Pyrogallol enhances therapeutic effect of human umbilical cord mesenchymal stem cells against LPS-mediated inflammation and lung injury via activation of Nrf2/HO-1 signaling

The main challenges in clinical applications of mesenchymal stem cells (MSCs) are attributed to their heterogeneity. It is believed that preconditioning of MSCs with active compounds may enhance the expression of potentially therapeutic molecules and thus achieve stable and effective therapeutic outcomes. In the present study, we investigated the mechanism by which pyrogallol increased the therapeutic efficacy of human umbilical cord mesenchymal stem cells (hUCMSCs) against LPS-induced acute lung injury (ALI). hUCMSCs with pyrogallol treatment increased expression of HO-1 at both mRNA and protein levels, accompanied by Kelch-Like ECH-Associated Protein 1 (Keap1) degradation, and upregulation of the Nrf2 protein levels as well as nuclear translocation of Nrf2. Moreover, the modulation of Keap1 and Nrf2 as well as HO-1 upregulation by pyrogallol was reversed by pretreatment with N-acetylcysteine (NAC) and a P38 kinase inhibitor (SB203580). Whereas, NAC pretreatment abrogated pyrogallol-mediated activation of P38 kinase, indicating that pyrogallol-derived ROS led to P38 kinase activation, thus promoting Nrf2/HO-1 signaling. Additionally, we found that the induction of p62 by the pyrogallol-mediated ROS/P38/Nrf2 axis interacted with Keap1 and resulted in autophagic degradation of Keap1, which created a positive feedback loop to further release of Nrf2. Furthermore, the increased expression of HO-1 in pyrogallol-pretreated hUCMSCs led to enhanced inhibitory effects on LPS-mediated TLR4/P-P65 signaling in BEAS-2B cells, resulting in increasing suppression of LPS-indued expression of a series of pro-inflammatory mediators. Compared to untreated hUCMSCs, Sprague-Dawley (SD) rats with pyrogallol-primed hUCMSCs transplantation showed enhanced improvements in LPS-mediated lung pathological alterations, the increased lung index (lung/body ratio), apoptosis of epithelial cells, the activation of TLR4/NF-κB signaling as well as the release of pro-inflammatory mediators. Together, these results suggested that hUCMSCs with pyrogallol pretreatment enhanced the therapeutic efficacy of hUCMSCs, which may provide a promising therapeutic strategy to maximize the therapeutic efficacy of hUCMSC-based therapy for treating LPS-associated ALI.

FAIM Enhances the Efficacy of Mesenchymal Stem Cell Transplantation by Inhibiting JNK-Induced c-FLIP Ubiquitination and Degradation

Background

The poor survival rates of transplanted mesenchymal stem cells (MSCs) in harsh microenvironments impair the efficacy of MSCs transplantation in myocardial infarction (MI). Extrinsic apoptosis pathways play an important role in the apoptosis of transplanted MSCs, and Fas apoptosis inhibitory molecule (FAIM) is involved in regulation of the extrinsic apoptosis pathway. Thus, we aimed to explore whether FAIM augmentation protects MSCs against stress-induced apoptosis and thereby improves the therapeutic efficacy of MSCs.

Methods

We ligated the left anterior descending coronary artery (LAD) in the mouse heart to generate an MI model and then injected FAIM-overexpressing MSCs (MSCs_FAIM) into the peri-infarction area in vivo. Moreover, FAIM-overexpressing MSCs were challenged with oxygen, serum, and glucose deprivation (OGD) in vitro, which mimicked the harsh microenvironment that occurs in cardiac infarction.

Results

FAIM was markedly downregulated under OGD conditions, and FAIM overexpression protected MSCs against OGD-induced apoptosis. MSCs_FAIM transplantation improved cell retention, strengthened angiogenesis, and ameliorated heart function. The antiapoptotic effect of FAIM was mediated by cellular-FLICE inhibitory protein (c-FLIP), and FAIM augmentation improved the protein expression of c-FLIP by reducing ubiquitin–proteasome-dependent c-FLIP degradation. Furthermore, FAIM inhibited the activation of JNK, and treatment with the JNK inhibitor SP600125 abrogated the reduction in c-FLIP protein expression caused by FAIM silencing.

Conclusions

Overall, these results indicated that FAIM curbed the JNK-mediated, ubiquitination–proteasome-dependent degradation of c-FLIP, thereby improving the survival of transplanted MSCs and enhancing their efficacy in MI. This study may provide a novel approach to strengthen the therapeutic effect of MSC-based therapy.

S-allylmercapto-N-acetylcysteine protects bone cells from oxidation and improves femur microarchitecture in healthy and diabetic mice

Oxidative stress is involved in the deterioration of bone quality and mechanical strength in both diabetic and aging adults. Therefore, we studied the ability of the antioxidant compound, S-allylmercapto-N-acetylcysteine (ASSNAC) to protect bone marrow stromal cells (BMSCs) from advanced glycation end-products (AGEs) cytotoxicity and improve bone microarchitecture of adult healthy and obese/diabetic (db/db) female mice. ASSNAC effect on AGEs-treated cultured rat BMSCs was evaluated by Neutral Red and XTT cell survival and reactive oxygen species (ROS) level assays. Its effect on healthy (C57BL/6) and obese/diabetic (C57BLKS/J Lepr^db+/+; db/db) female mice femur parameters, such as (1) number of adherent BMSCs, (2) percentage of CD73⁺/CD45^- cells in bone marrow (BM), (3) glutathione level in BM cells, and (4) femur microarchitecture parameters by microcomputed tomography, was studied. ASSNAC treatment protected BMSCs by significantly decreasing AGEs-induced ROS production and increasing their cellular resistance to the cytotoxic effect of AGEs. ASSNAC treatment of healthy female mice (50 mg/kg/day; i.p.; age 12-20 weeks) significantly increased the number of BMSCs (+60%), CD73⁺/CD45^- cells (+134%), and glutathione level (+110%) in the femur bone marrow. Furthermore, it increased the femur length (+3%), cortical diameter (+3%), and cortical areal moment of inertia (Ct.MOI; +10%) a surrogate for biomechanical strength. In db/db mice that demonstrated a compromised trabecular bone and growth plate microarchitecture, ASSNAC treatment restored the trabecular number (Tb.N, +29%), bone volume fraction (Tb.BV/TV, +130%), and growth plate primary spongiosa volumetric bone mineral density (PS-vBMD, +7%) and thickness (PS-Th, +18%). In conclusion, this study demonstrates that ASSNAC protects bone marrow cells from oxidative stress and may improve bone microarchitecture in adult healthy and diabetic female mice.

Coenzyme Q10 inhibits intracranial aneurysm formation and progression in a mouse model

BACKGROUND

The aim of this study was to investigate the effect of coenzyme Q10 (CoQ10), a commonly used nutritional supplement, on intracranial aneurysm (IA) initiation and progression in a mouse model, as well as the mechanism.

METHODS

Hydrogen peroxide (H₂O₂) was used to treat mouse-derived vascular smooth muscle cells (VSMCs) to induce oxidative injury, followed by incubation with CoQ10. In the mouse IA model established by elastase injection, CoQ10 was orally administered at 10 mg/kg every other day for 14 days, during which the incidence of IA, rupture rate, symptom-free survival, and systolic blood pressure were recorded.

RESULTS

CoQ10 promoted the expression of nuclear factor erythroid 2-related factor 2 and antioxidant enzymes. In H₂O₂-treated VSMCs, reactive oxygen species and cell apoptosis were reduced by CoQ10. In IA mice, CoQ10 treatment decreased the rupture rate of IA, improved the symptom-free survival, and reduced systolic blood pressure. Macrophage infiltration and expression of pro-inflammatory cytokines in the cerebral arteries were mitigated by CoQ10 treatment.

CONCLUSIONS

CoQ10 is effective in reducing oxidative stress in VSMCs, thereby attenuating IA formation and rupture in mice. CoQ10 also alleviates inflammation and restores normal phenotypes of VSMCs in the cerebral arteries. Our data suggest that CoQ10 is a potentially effective drug for managing IA.

IMPACT

To investigate the effect of CoQ10, a commonly used nutritional supplement, on IA initiation and progression in a mouse model, as well as the mechanism. CoQ10 promoted the expression of Nrf2 and antioxidant enzymes. In H₂O₂-treated VSMCs, ROS and cell apoptosis were reduced by CoQ10. CoQ10 is effective in reducing oxidative stress in VSMCs, thereby attenuating IA formation and rupture in mice.

Glucose-6-Phosphate Dehydrogenase, Redox Homeostasis and Embryogenesis

Normal embryogenesis requires complex regulation and precision, which depends on multiple mechanistic details. Defective embryogenesis can occur by various mechanisms. Maintaining redox homeostasis is of importance during embryogenesis. NADPH, as produced from the action of glucose-6-phosphate dehydrogenase (G6PD), has an important role in redox homeostasis, serving as a cofactor for glutathione reductase in the recycling of glutathione from oxidized glutathione and for NADPH oxidases and nitric oxide synthases in the generation of reactive oxygen (ROS) and nitrogen species (RNS). Oxidative stress differentially influences cell fate and embryogenesis. While low levels of stress (eustress) by ROS and RNS promote cell growth and differentiation, supra-physiological concentrations of ROS and RNS can lead to cell demise and embryonic lethality. G6PD-deficient cells and organisms have been used as models in embryogenesis for determining the role of redox signaling in regulating cell proliferation, differentiation and migration. Embryogenesis is also modulated by anti-oxidant enzymes, transcription factors, microRNAs, growth factors and signaling pathways, which are dependent on redox regulation. Crosstalk among transcription factors, microRNAs and redox signaling is essential for embryogenesis.

Studies on Regulation of Global Protein Profile and Cellular Bioenergetics of Differentiating SH-SY5Y Cells

The SH-SY5Y cells differentiated by sequential exposure of retinoic acid (RA) and brain-derived neurotrophic growth factor (BDNF) are a well-employed cellular model for studying the mechanistic aspects of neural development and neurodegeneration. Earlier studies from our lab have identified dramatic upregulation (77 miRNAs) and downregulation (17 miRNAs) of miRNAs in SH-SY5Y cells differentiated with successive exposure of RA + BDNF and demonstrated the essential role of increased levels of P53 proteins in coping with the differentiation-induced changes in protein levels. In continuation to our earlier studies, we have performed unbiased LC-MS/MS global protein profiling of naïve and differentiated SH-SY5Y cells and analyzed the identified proteins in reference to miRNAs identified in our earlier studies to identify the cellular events regulated by both identified miRNAs and proteins. Analysis of LC-MS/MS data has shown a significant increase and decrease in levels of 215 and 163 proteins, respectively, in differentiated SH-SY5Y cells. Integrative analysis of miRNA identified in our previous studies and protein identified in the present study is carried out to discover novel miRNA-protein regulatory modules to elucidate miRNA-protein regulatory relationships of differentiating neurons. In silico network analysis of miRNAs and proteins deregulated upon SH-SY5Y differentiation identified cell cycle, synapse formation, axonogenesis, differentiation, neuron projection, and neurotransmission, as the topmost involved pathways. Further, measuring mitochondrial dynamics and cellular bioenergetics using qPCR and Seahorse XFp Flux Analyzer, respectively, showed that differentiated cells possess increased mitochondrial dynamics and OCR relative to undifferentiated cells. In summary, our studies have identified a novel set of proteins deregulated during neuronal differentiation and establish the role of miRNAs identified in earlier studies in the regulation of proteins identified by LC-MS/MS-based global profiling of differentiating neurons, which will help in future studies related to neural development and neurodegeneration.

Mesenchymal stem cells have ameliorative effect on the colitis model via Nrf2/HO-1 pathway

Purpose:

To evaluate the ameliorative effect of mesenchymal stem cells (MSCs) on acetic acid colitis model via Nrf2/HO-1 pathway in rats.

Methods:

In this study, 30 rats were divided into three groups. Acute colitis was induced by rectal administration of 4% solution of acetic acid. MSCs were injected intraperitoneally in the treatment group.

Results:

Increased levels of tumor necrosis factor-α (TNF-α), pentraxin-3, and malondialdehyde (MDA) in colitis group were revealed biochemically. Increased level of TNF-α and decreased levels of Nrf2 and interleukin-10 (IL-10) were observed in rectum tissues. Increased fibrous tissue proliferation, vascularization and inflammatory cell infiltration were described in the colitis group. Significant improvement was observed in MSCs treated group histopathologically. Increased immunopositivity of TNF-α, vascular endothelial growth factor (VEGF) and CD68 markers was observed in the colitis group cells, and decreased level of this positivity was observed in MSCs treated group.

Conclusions:

Biochemical, histopathological and immunohistochemical results strongly support the ameliorative effect of MSCs against acetic induced colitis model via Nrf2/HO-1 pathway in rats.

The Role of NRF2 in Bone Metabolism - Friend or Foe?

Bone metabolism is closely related to oxidative stress. As one of the core regulatory factors of oxidative stress, NRF2 itself and its regulation of oxidative stress are both involved in bone metabolism. NRF2 plays an important and controversial role in the regulation of bone homeostasis in osteoblasts, osteoclasts and other bone cells. The role of NRF2 in bone is complex and affected by several factors, such as its expression levels, age, sex, the presence of various physiological and pathological conditions, as well as its interaction with certains transcription factors that maintain the normal physiological function of the bone tissue. The properties of NRF2 agonists have protective effects on the survival of osteogenic cells, including osteoblasts, osteocytes and stem cells. Activation of NRF2 directly inhibits osteoclast differentiation by resisting oxidative stress. The effects of NRF2 inhibition and hyperactivation on animal skeleton are still controversial, the majority of the studies suggest that the presence of NRF2 is indispensable for the acquisition and maintenance of bone mass, as well as the protection of bone mass under various stress conditions. More studies show that hyperactivation of NRF2 may cause damage to bone formation, while moderate activation of NRF2 promotes increased bone mass. In addition, the effects of NRF2 on the bone phenotype are characterized by sexual dimorphism. The efficacy of NRF2-activated drugs for bone protection and maintenance has been verified in a large number of in vivo and in vitro studies. Additional research on the role of NRF2 in bone metabolism will provide novel targets for the etiology and treatment of osteoporosis.

Cashing in on ferroptosis against tumor cells: Usher in the next chapter

Ferroptosis is a new type of non-apoptotic regulated cell death (RCD) driven by unrestricted lethal lipid peroxidation, which is totally distinct from other forms of RCD in genetic and biochemical characteristics. It is generally believed that iron dependency, malfunction of the redox system, and excessive lipid peroxidation are the main hallmarks of ferroptosis. Accumulating pieces of evidence over the past few years have shown that ferroptosis is tightly related to various types of diseases, especially cancers. Ferroptosis has recently attracted great attention in the field of cancer research. A plethora of evidence shows that employing ferroptosis as a powerful weapon can remarkably enhance the efficacy of tumor cell annihilation. Better knowledge of the ferroptosis mechanisms and their interplay with cancer biology would enable us to use this fashionable tool in the best way. Herein, we will briefly present the relevant mechanisms of ferroptosis, the multifaceted relation between ferroptosis and cancer, encompassing tumor immunity, overcoming chemoresistance, and epithelial to mesenchymal transition. In the end, we will also briefly discuss the potential approaches to ferroptosis-based cancer therapy, such as using drugs and small molecules, nanoparticles, mitochondrial targeting, and photodynamic therapy.

A standardized extract of Asparagus officinalis stem improves HSP70-mediated redox balance and cell functions in bovine cumulus-granulosa cells

Heat shock (HS) protein 70 (HSP70), a well-known HS-induced protein, acts as an intracellular chaperone to protect cells against stress conditions. Although HS induces HSP70 expression to confer stress resistance to cells, HS causes cell toxicity by increasing reactive oxygen species (ROS) levels. Recently, a standardized extract of Asparagus officinalis stem (EAS), produced from the byproduct of asparagus, has been shown to induce HSP70 expression without HS and regulate cellular redox balance in pheochromocytoma cells. However, the effects of EAS on reproductive cell function remain unknown. Here, we investigated the effect of EAS on HSP70 induction and oxidative redox balance in cultured bovine cumulus-granulosa (CG) cells. EAS significantly increased HSP70 expression; however, no effect was observed on HSP27 and HSP90 under non-HS conditions. EAS decreased ROS generation and DNA damage and increased glutathione (GSH) synthesis under both non-HS and HS conditions. Moreover, EAS synergistically increased HSP70 and HSF1 expression and increased progesterone levels in CG cells. Treatment with an HSP70 inhibitor significantly decreased GSH level, increased ROS level, and decreased HSF1, Nrf2, and Keap1 expression in the presence of EAS. Furthermore, EAS significantly increased progesterone synthesis. Thus, EAS improves HSP70-mediated redox balance and cell function in bovine CG cells.

Combination Therapy of Metadichol Nanogel and Lipocalin-2 Engineered Mesenchymal Stem Cells Improve Wound Healing in Rat Model of Excision Injury

Purpose: Currently, several disorders including burns, trauma, excisional and diabetic wounds, and bedsores threaten the human health. Application of mesenchymal stem cells (MSCs) is recommended for treatment of skin disorders. However, because of oxidative stress and inflammation after skin injury, survival of transplanted MSCs is low which in turn negatively affects the efficiency of the MSCs-based therapy. In an attempt to address the aforementioned challenge and introducing a novel potential therapeutic strategy, we employed combination therapy by lipocalin 2 (Lcn2)-engineered MSCs and a Metadichol (an inverse agonist of vitamin D receptor (VDR)) nanogel in a rat model of excisional wound.

Methods: First, human umbilical cord MSCs (hUC-MSCs) was transfected by a recombinant plasmid encoding Lcn2 gene. Next, a combination of Metadichol nanogel and the engineered MSCs was co-applied on wound in rat model of excision injury. Finally the improvement of wound healing in experimental groups was evaluated by photography and histological assessments (hematoxylin and eosin staining).

Results: Our findings revealed that the repair rate was higher in the group received combination therapy comparing to control groups. Notably, Metadichol+Lcn2-MSCs showed significantly higher wound contraction rate compared to control group at all time points (P value < 0.001). Furthermore, wound repair rate was 95% 14 days after surgery, and 100% after 21 days in the treatment groups. Our results also revealed that the combination therapy improved and accelerated the wound healing process.

Conclusion: Our findings suggest a novel potential therapeutic strategy i.e. Lcn2-engineered MSCs and Metadichol for wound healing. However, further preclinical and clinical studies are required.

Dimethyl fumarate prevents cytotoxicity and apoptosis mediated by oxidative stress in human adipose-derived mesenchymal stem cells

BACKGROUND

The poor survival rate and undesirable homing of transplanted stem cells are the major challenges in stem cell therapy. Addressing the challenge would improve the therapeutic efficacy of these cells. Dimethyl fumarate (DMF) is an anti-inflammatory drug that exerts its effects through the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Therefore, its cytoprotective effects on human adipose-derived MSCs (hASCs) against various oxidative stresses have been investigated in this study.

METHODS AND RESULTS

hASCs were cultured with different concentrations of DMF to evaluate the cytotoxicity of DMF on hASCs using Cell Counting Kit-8 (CCK-8). Besides, the migration ability of the cells after DMF treatment was evaluated using the Transwell method. Furthermore, the expression of HO-1 and NQO-1 was determined using RT-PCR. The cytoprotective effects of DMF on hASCs against the oxidative stress caused by H₂O₂ and Ultra Violet (UV) were evaluated by assessing cell proliferation and apoptosis. Our results demonstrated that under oxidative stress conditions induced by H₂O₂ and UV, DMF increased the survival rate and proliferation of the cells and prevented apoptosis. Moreover, the expression of HO-1 and NQO-1 was upregulated in hASCs pretreated with DMF which confirms the activation of the Nrf2 pathway. However, DMF significantly decreased migration in hADSCs (P < 0.0001).

CONCLUSION

Our findings indicate that DMF enhances the proliferation capability and viability of hASCs and prevents their apoptosis in harsh stressful microenvironments. However, the applicability of DMF as a cytoprotective factor for the augmentation of hASCs requires in-depth preclinical and clinical studies.

SA/G hydrogel containing NRF2-engineered HEK-293-derived CM improves wound healing efficacy of WJ-MSCs in a rat model of excision injury

AIM OF THE STUDY

Skin wounds are a major public health issue due to the lack of real effective remedies. Mesenchymal stem cells (MSCs) are considered as a promising therapeutic strategy for wound injuries; however, low survival rate following transplantation limited their application. In an attempt to introduce a novel potential wound dressing and improve wound healing properties, the current study was conducted.

MATERIAL AND METHODS

we prepared conditioned medium (CM) harvested from HEK-293 cells overexpressing nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of antioxidant genes expression. Then, the CM was loaded in a biodegradable hydrogel. Next, in an animal model of full-thickness excision wound, wharton's jelly derived-mesenchymal stem cells (WJ-MSCs) were transplanted at the margins of the wound followed by application of the hydrogel on injury site. Finally, wound healing characteristics were evaluated by proper methods.

RESULTS

Our findings revealed that, the NRF2-CM protected the WJ-MSCs against H₂O₂-induced toxicity in vitro. Furthermore, in vivo results showed that, SA/G hydrogel containing NRF2-CM significantly (P < 0.01) promoted WJ-MSCs survival, increased angiogenesis, accelerated wound contraction, and promoted wound healing compared to other groups.

CONCLUSION

Though further preclinical and clinical studies regarding mechanisms behind the protection and also safety of the strategy are needed, our findings strongly suggest that the prepared wound dressing enhanced the efficacy of therapeutic potential of WJ-MSCs by providing an enriched/antioxidant niche support.

Epigenetic plasticity and redox regulation of neural stem cell state and fate

The neural stem cells (NSCs) are essential for normal brain development and homeostasis. The cell state (i.e. quiescent versus activated) and fate (i.e. the cell lineage of choice upon differentiation) of NSCs are tightly controlled by various redox and epigenetic regulatory mechanisms. There is an increasing appreciation that redox and epigenetic regulations are intimately linked, but how this redox-epigenetics crosstalk affects NSC activity remains poorly understood. Another unresolved topic is whether the NSCs actually contribute to brain ageing and neurodegenerative diseases. In this review, we aim to 1) distill concepts that underlie redox and epigenetic regulation of NSC state and fate; 2) provide examples of the redox-epigenetics crosstalk in NSC biology; and 3) highlight potential redox- and epigenetic-based therapeutic opportunities to rescue NSC dysfunctions in ageing and neurodegenerative diseases.

Transplantation of Umbilical Cord-Derived Mesenchymal Stem Cells Overexpressing Lipocalin 2 Ameliorates Ischemia-Induced Injury and Reduces Apoptotic Death in a Rat Acute Myocardial Infarction Model

Myocardial infarction (MI) is a leading cause of death worldwide and requires development of efficient therapeutic strategies . Mesenchymal stem cells (MSCs) -based therapy of MI has been promising but inefficient due to undesirable microenvironment of the infarct tissue. Hence, the current study was conducted to fortify MSCs against the unfavorable microenvironment of infarct tissue via overexpression of Lipocalin 2 (Lcn2) as a cytoprotective factor. The engineered cells (Lcn2-MSCs) were transplanted to infarcted heart of a rat model of MI. According to our findings, Lcn2 overexpression resulted in increased MSCs survival in the MI tissue (p < 0.05) compared to non-engineered cells. Furthermore, the infusion of Lcn2-MSCs mitigated Left ventricle (LV) remodeling, decreased fibrosis (p < 0.0001), and reduced apoptotic death of the LVs' cells (p < 0.0001) compared to the control. Our findings suggest a potential novel therapeutic strategy for MI, however, further investigations such as safety and efficacy assessments in large animals followed by clinical trials are required.

MSCs and Inflammatory Cells Crosstalk in Regenerative Medicine: Concerted Actions for Optimized Resolution Driven by Energy Metabolism

Mesenchymal stromal cells (MSCs) are currently widely used in cell based therapy regarding to their remarkable efficacy in controlling the inflammatory status in patients. Despite recent progress and encouraging results, inconstant therapeutic benefits are reported suggesting that significant breakthroughs in the understanding of MSCs immunomodulatory mechanisms of action remains to be investigated and certainly apprehended from original point of view. This review will focus on the recent findings regarding MSCs close relationship with the innate immune compartment, i.e. granulocytes and myeloid cells. The review will also consider the intercellular mechanism of communication involved, such as factor secretion, cell-cell contact, extracellular vesicles, mitochondria transfer and efferocytosis. Immune-like-properties of MSCs supporting part of their therapeutic effect in the clinical setting will be discussed, as well as their potentials (immunomodulatory, anti-bacterial, anti-inflammatory, anti-oxidant defenses and metabolic adaptation…) and effects mediated, such as cell polarization, differentiation, death and survival on various immune and tissue cell targets determinant in triggering tissue regeneration. Their metabolic properties in term of sensing, reacting and producing metabolites influencing tissue inflammation will be highlighted. The review will finally open to discussion how ongoing scientific advances on MSCs could be efficiently translated to clinic in chronic and age-related inflammatory diseases and the current limits and gaps that remain to be overcome to achieving tissue regeneration and rejuvenation.

Mesenchymal Stem Cells Transplantation in Intracerebral Hemorrhage: Application and Challenges

Intracerebral hemorrhage (ICH) is one of the leading causes of death and long-term disability worldwide. Mesenchymal stem cell (MSC) therapies have demonstrated improved outcomes for treating ICH-induced neuronal defects, and the neural network reconstruction and neurological function recovery were enhanced in rodent ICH models through the mechanisms of neurogenesis, angiogenesis, anti-inflammation, and anti-apoptosis. However, many key issues associated with the survival, differentiation, and safety of grafted MSCs after ICH remain to be resolved, which hinder the clinical translation of MSC therapy. Herein, we reviewed an overview of the research status of MSC transplantation after ICH in different species including rodents, swine, monkey, and human, and the challenges for MSC-mediated ICH recovery from pathological microenvironment have been summarized. Furthermore, some efficient strategies for the outcome improvement of MSC transplantation were proposed.

Harnessing adipose‑derived stem cells to release specialized secretome for the treatment of hepatitis B

Mesenchymal stem cells (MSCs) have the function of repairing damaged tissue, which is known to be mediated by the secretome, the collection of secretory materials shed from MSCs. Adjusting the culture conditions of MSCs can lead to a significant difference in the composition of the secretome. It was hypothesized that pre‑sensitization of MSCs with specific disease‑causing agents could harness MSCs to release the therapeutic materials specialized for the disease. To validate this hypothesis, the present study aimed to generate a 'disease‑specific secretome' for hepatitis caused by hepatitis B virus using hepatitis BX antigen (HBx) as a disease‑causing material. Secretary materials (HBx‑IS) were collected following the stimulation of adipose‑derived stem cells (ASCs) with 100‑fold diluted culture media of AML12 hepatocytes that had been transfected with pcDNA‑HBx for 24 h. An animal model of hepatitis B was generated by injecting HBx into mice, and the mice were subsequently intravenously administered a control secretome (CS) or HBx‑IS. Compared with the CS injection, the HBx‑IS injection significantly reduced the serum levels of interleukin‑6 and tumor necrosis factor‑α (pro‑inflammatory cytokines). Western blot analysis and immunohistochemistry of the liver specimens revealed that the HBx‑IS injection led to a higher expression of liver regeneration‑related markers, including hepatocyte growth factor and proliferating cell nuclear antigen, a lower expression of pro‑apoptotic markers, such as cleaved caspase 3 and Bim in mouse livers, and a lower expression of pro‑inflammatory markers (F4/80 and CD68) compared to the CS injection. HBx‑IS exhibited higher liver regenerative, anti‑inflammatory and anti‑apoptotic properties, particularly in the mouse model of hepatitis B compared to CS. This suggests that the secretome obtained by stimulating ASCs with disease‑causing agents may have a more prominent therapeutic effect on the specific disease than the naïve secretome.

Novel Interplay between p53 and HO-1 in Embryonic Stem Cells

Stem cells genome safeguarding requires strict oxidative stress control. Heme oxygenase-1 (HO-1) and p53 are relevant components of the cellular defense system. p53 controls cellular response to multiple types of harmful stimulus, including oxidative stress. Otherwise, besides having a protective role, HO-1 is also involved in embryo development and in embryonic stem (ES) cells differentiation. Although both proteins have been extensively studied, little is known about their relationship in stem cells. The aim of this work is to explore HO-1-p53 interplay in ES cells. We studied HO-1 expression in p53 knockout (KO) ES cells and we found that they have higher HO-1 protein levels but similar HO-1 mRNA levels than the wild type (WT) ES cell line. Furthermore, cycloheximide treatment increased HO-1 abundance in p53 KO cells suggesting that p53 modulates HO-1 protein stability. Notably, H₂O₂ treatment did not induce HO-1 expression in p53 KO ES cells. Finally, SOD2 protein levels are also increased while Sod2 transcripts are not in KO cells, further suggesting that the p53 null phenotype is associated with a reinforcement of the antioxidant machinery. Our results demonstrate the existence of a connection between p53 and HO-1 in ES cells, highlighting the relationship between these stress defense pathways.

Hydrogen Peroxide-Preconditioned Human Adipose-Derived Stem Cells Enhance the Recovery of Oligodendrocyte-Like Cells after Oxidative Stress-Induced Damage

Oxidative stress associated with neuroinflammation is a key process involved in the pathophysiology of neurodegenerative diseases, and therefore, has been proposed as a crucial target for new therapies. Recently, the therapeutic potential of human adipose-derived stem cells (hASCs) has been investigated as a novel strategy for neuroprotection. These cells can be preconditioned by exposing them to mild stress in order to improve their response to oxidative stress. In this study, we evaluate the therapeutic potential of hASCs preconditioned with low doses of H₂O₂ (called HC016 cells) to overcome the deleterious effect of oxidative stress in an in vitro model of oligodendrocyte-like cells (HOGd), through two strategies: i, the culture of oxidized HOGd with HC016 cell-conditioned medium (CM), and ii, the indirect co-culture of oxidized HOGd with HC016 cells, which had or had not been exposed to oxidative stress. The results demonstrated that both strategies had reparative effects, oxidized HC016 cell co-culture being the one associated with the greatest recovery of the damaged HOGd, increasing their viability, reducing their intracellular reactive oxygen species levels and promoting their antioxidant capacity. Taken together, these findings support the view that HC016 cells, given their reparative capacity, might be considered an important breakthrough in cell-based therapies.

Sesn2 attenuates the damage of endothelial progenitor cells induced by angiotensin II through regulating the Keap1/Nrf2 signal pathway

Endothelial progenitor cell (EPC) dysfunction is an important physiopathological mechanism in the dynamics of the formation of atherosclerosis. It has been reported that angiotensin II (Ang-II) damages the function of EPCs in atherosclerotic plaque through induction of oxidative stress. Sestrin 2 (Sesn2) serves as an antioxidant role in oxidative stress, however, the exact mechanisms underlying the dynamics of how Sesn2 may factor into EPCs after Ang-II treatments needs to be illustrated. We isolated EPCs from human umbilical cord blood samples and treated with Ang-II. Western blotting, qRT-PCR, transwell assays, immunofluorescence and so on were used to investigate the mechanisms underlying the roles of Sesn2 in EPCs treated with Ang-II. Ang-II was found to promote the apoptosis of EPCs as well as inhibited the mRNA and protein expression of Sesn2. Upregulation of Sesn2 attenuated the negative effect of Ang-II. Sesn2 increased the protein expression of Nrf2 by enhancing P62-dependent autophagy. Silencing of Nrf2 enhanced the degree of apoptosis of EPCs as well as resulted in the impairment of EPC functions through inducing the promotion of (reactive oxygen species) ROS production. Our study results indicated that Sesn2 facilitated the viability of EPCs After treatment with Ang-II, as well as provided a potential therapeutic target to alleviate the progression of atherosclerosis.

Iron depletion with deferoxamine protects bone marrow-derived mesenchymal stem cells against oxidative stress-induced apoptosis

Bone marrow mesenchymal stem cells (BM-MSCs) are multipotent cells with self-renewal properties, making them an ideal candidate for regenerative medicine. Recently, numerous studies show that about more than 99% of transplanted cells are destroyed because of the stressful microenvironment. Meanwhile, in the target organs, iron overload can produce oxidative stress introducing it as the most important stress factor. The present study was aimed at increasing BM-MSCs' viability against oxidative stress microenvironment using iron depletion by deferoxamine (DFO). Mesenchymal stem cells are isolated and characterized from rat bone marrow. Then, the sensitivity of BM-MSCs against H2O2-induced oxidative stress was evaluated through half of the inhibitory concentration (IC50) estimation by using MTT assay. The maximum non-inhibitory concentration of DFO on BM-MSCs was determined. The next step was the comparison between DFO pre-treated BM-MSCs and untreated cells against H2O2-induced apoptosis. BM-MSCs were identified with morphologic and flow cytometry analysis. IC50 of H2O2 was determined as 0.55 mM at 4 h. Also, the maximum non-inhibitory concentration of DFO was ascertained as 5 μM at 48 h. Our results demonstrated that pretreatment with DFO significantly potentiates BM-MSCs against H2O2-induced oxidative stress which was confirmed by MTT assay, AO/EB double staining, DAPI staining, and activated caspase 3 quantification as well as western blot test. Expression of cleaved caspase 3 and pAKT/AKT ratio obviously demonstrated DFO can resist the cells against cytotoxicity. These findings may help to develop better stem cell culture medium for MSC-based cell therapy. Moreover, regulation of cell stress can be used in practical subjects.

Immunomodulatory and Antioxidative potentials of adipose-derived Mesenchymal stem cells isolated from breast versus abdominal tissue: a comparative study

BACKGROUND

Adipose-derived stem cells (ASCs) are considered ideal candidates for both research and cellular therapy due to ease of access, large yield, feasibility, and efficacy in preclinical and clinical studies. Unlike the subcutaneous abdominal fat depot, breast ASCs features are still not well recognized, limiting their possible therapeutic use. ASCs were found to exert immunomodulatory and antioxidative activities for maintaining homeostasis and functionality of diseased/damaged tissues. This study aims to investigate the immunomodulatory and antioxidative potentials of breast versus abdominal isolated ASCs to find out which anatomical site provides ASCs with better immunoregulatory and oxidative stress resistance capabilities.

METHODS

ASCs were isolated from abdominal and breast tissues. Gene expression analysis was conducted for a panel of immunomodulatory and antioxidative genes, as well as adipokines and proliferation genes. Flow cytometric analysis of a group of immunomodulatory surface proteins was also performed. Finally, the significantly expressed genes have undergone protein-protein interaction and functional enrichment in silico analyses.

RESULTS

Our results revealed similar morphological and phenotypic characteristics for both breast and abdominal ASCs. However, a significant elevation in the expression of two potent immunosuppressive genes, IL-10 and IDO as well as the expression of the multifaceted immunomodulatory adipokine, visfatin, was detected in breast versus abdominal ASCs. Moreover, a significant overexpression of the antioxidative genes, GPX1, SIRT5, and STAT3 and the proliferation marker, Ki67, was also observed in breast ASCs relative to abdominal ones. In silico analysis showed that both of the differentially upregulated immunomodulatory and antioxidative mediators integratively involved in multiple biological processes and pathways indicating their functional association.

CONCLUSION

Breast ASCs possess superior immunomodulatory and antioxidative capabilities over abdominal ASCs. Our findings shed light on the possible therapeutic applications of breast ASCs in immune-related and oxidative stress-associated diseases.

Vascular toxicity associated with anti-angiogenic drugs

Over the past two decades, the treatment of cancer has been revolutionised by the highly successful introduction of novel molecular targeted therapies and immunotherapies, including small-molecule kinase inhibitors and monoclonal antibodies that target angiogenesis by inhibiting vascular endothelial growth factor (VEGF) signaling pathways. Despite their anti-angiogenic and anti-cancer benefits, the use of VEGF inhibitors (VEGFi) and other tyrosine kinase inhibitors (TKIs) has been hampered by potent vascular toxicities especially hypertension and thromboembolism. Molecular processes underlying VEGFi-induced vascular toxicities still remain unclear but inhibition of endothelial NO synthase (eNOS), reduced nitric oxide (NO) production, oxidative stress, activation of the endothelin system, and rarefaction have been implicated. However, the pathophysiological mechanisms still remain elusive and there is an urgent need to better understand exactly how anti-angiogenic drugs cause hypertension and other cardiovascular diseases (CVDs). This is especially important because VEGFi are increasingly being used in combination with other anti-cancer dugs, such as immunotherapies (immune checkpoint inhibitors (ICIs)), other TKIs, drugs that inhibit epigenetic processes (histone deacetylase (HDAC) inhibitor) and poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors, which may themselves induce cardiovascular injury. Here, we discuss vascular toxicities associated with TKIs, especially VEGFi, and provide an up-to-date overview on molecular mechanisms underlying VEGFi-induced vascular toxicity and cardiovascular sequelae. We also review the vascular effects of VEGFi when used in combination with other modern anti-cancer drugs.

PARK7 Diminishes Oxidative Stress-Induced Mucosal Damage in Celiac Disease

Coeliac disease (CD) is a chronic, immune-mediated small intestinal enteropathy, accompanied with gluten-triggered oxidative damage of duodenal mucosa. Previously, our research group reported an increased mucosal level of the antioxidant protein Parkinson's disease 7 (PARK7) in children with CD. In the present study, we investigated the role of increased PARK7 level on the epithelial cell and mucosal integrity of the small intestine. The presence of PARK7 was investigated using immunofluorescent staining on duodenal mucosa of children with CD and on FHs74Int duodenal epithelial cells. To investigate the role of oxidative stress, FHs74Int cells were treated with H₂O₂ in the absence or presence of Comp23, a PARK7-binding compound. Intracellular accumulation of reactive oxygen species (ROS) was determined by DCFDA-based assay. Cell viability was measured by MTT, LDH, and Annexin V apoptosis assays. Disruption of cytoskeleton and cell adhesion was investigated by immunofluorescence staining and by real-time RT PCR. Effect of PARK7 on mucosal permeability was investigated ex vivo using intestinal sacs derived from control and Comp-23-pretreated mice. Comp23 treatment reduced the H₂O₂-induced intracellular accumulation of ROS, thus preserving the integrity of the cytoskeleton and also the viability of the FHs74Int cells. Accordingly, Comp23 treatment increased the expression of antioxidants (NRF2, TRX1, GCLC, HMOX1, NQO1), cell-cycle regulators (TP53, CDKN1A, PCNA, BCL2, BAX), and cell adhesion molecules (ZO1, CDH1, VCL, ITGB5) of H₂O₂-treated cells. Pretreatment with Comp23 considerably decreased the small intestinal permeability. In this study, we demonstrate that PARK7-binding Comp23 reduces the oxidative damage of duodenal epithelial cells, via increased expression of NRF2- and P53-regulated genes. Our results suggest that PARK7 plays a significant role in the maintenance of mucosal integrity in CD.

H2O2-preconditioned human adipose-derived stem cells (HC016) increase their resistance to oxidative stress by overexpressing Nrf2 and bioenergetic adaptation

BACKGROUND

Mesenchymal stem cells, including those derived from human adipose tissue (hASCs), are currently being widely investigated for cell therapy. However, when transplanted at the site of injury, the survival and engraftment rates of hASCs are low, mainly due to the harsh microenvironment they encounter, characterized by inflammation and oxidative stress. To overcome these therapeutic limitations, cell preconditioning with low-concentration of hydrogen peroxide (H2O2) has been proposed as a plausible strategy to increase their survival and adaptation to oxidative stress. Nonetheless, the underlying mechanisms of this approach are not yet fully understood. In this study, we analyzed molecular and bioenergetic changes that take place in H2O2 preconditioned hASCs.

METHODS

Long-term exposure to a low concentration of H2O2 was applied to obtain preconditioned hASCs (named HC016), and then, their response to oxidative stress was analyzed. The effect of preconditioning on the expression of Nrf2 and its downstream antioxidant enzymes (HO-1, SOD-1, GPx-1, and CAT), and of NF-κB and its related inflammatory proteins (COX-2 and IL-1β), were examined by Western blot. Finally, the Seahorse XF96 Flux analysis system was used to evaluate the mitochondrial respiration and glycolytic function, along with the total ATP production.

RESULTS

We found that under oxidative conditions, HC016 cells increased the survival by (i) decreasing intracellular ROS levels through the overexpression of the transcription factor Nrf2 and its related antioxidant enzymes HO-1, SOD-1, GPx-1, and CAT; (ii) reducing the secretion of pro-inflammatory molecules COX-2 and IL-1β through the attenuation of the expression of NF-κB; and (iii) increasing the total ATP production rate through the adaption of their metabolism to meet the energetic demand required to survive.

CONCLUSIONS

H2O2 preconditioning enhances hASC survival under oxidative stress conditions by stimulating their antioxidant response and bioenergetic adaptation. Therefore, this preconditioning strategy might be considered an excellent tool for strengthening the resistance of hASCs to harmful oxidative stress.

Flavolignans from Silymarin as Nrf2 Bioactivators and Their Therapeutic Applications

Silymarin (SM) is a mixture of flavolignans extracted from the seeds of species derived from Silybum marianum, commonly known as milk thistle or St. Mary'sthistle. These species have been widely used in the treatment of liver disorders in traditional medicine since ancient times. Several properties had been attributed to the major SM flavolignans components, identified as silybin, isosilybin, silychristin, isosilychristin, and silydianin. Previous research reported antioxidant and protective activities, which are probably related to the activation of the nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), known as a master regulator of the cytoprotector response. Nrf2 is a redox-sensitive nuclear transcription factor able to induce the downstream-associated genes. The disruption of Nrf2 signaling has been associated with different pathological conditions. Some identified phytochemicals from SM had shown to participate in the Nrf2 signaling pathway; in particular, they have been suggested as activators that disrupt interactions in the Keap1-Nrf2 system, but also as antioxidants or with additional actions regarding Nrf2 regulation. Thus, the study of these molecules makes them appear attractive as novel targets for the treatment or prevention of several diseases.

Vascular Cardio-Oncology: Vascular Endothelial Growth Factor inhibitors and hypertension

Since the formation of new blood vessels is essential for tumour growth and metastatic spread, inhibition of angiogenesis by targeting the vascular endothelial growth factor (VEGF) pathway is an effective strategy for various types of cancer, most importantly renal cell carcinoma, thyroid cancer, and hepatocellular carcinoma. However, VEGF inhibitors have serious side effects, most importantly hypertension and nephropathy. In case of fulminant hypertension, this may only be handled by lowering the dosage since the blood pressure rise is proportional to the amount of VEGF inhibition. These effects pathophysiologically and clinically resemble the most severe complication of pregnancy, preeclampsia, in which case an insufficient placenta leads to a rise in sFlt-1 levels causing a decrease in VEGF availability. Due to this overlap, studies in preeclampsia may provide important information for VEGF inhibitor-induced toxicity and vice versa. In both VEGF inhibitor-induced toxicity and preeclampsia, endothelin (ET)-1 appears to be a pivotal player. In this review, after briefly summarizing the anticancer effects, we discuss the mechanisms that potentially underlie the unwanted effects of VEGF inhibitors, focusing on ET-1, nitric oxide and oxidative stress, the renin-angiotensin-aldosterone system, and rarefaction. Given the salt sensitivity of this phenomenon, as well as the beneficial effects of aspirin in preeclampsia and cancer, we next provide novel treatment options for VEGF inhibitor-induced toxicity, including salt restriction, ET receptor blockade, and cyclo-oxygenase inhibition, in addition to classical antihypertensive and renoprotective drugs. We conclude with the recommendation of therapeutic drug monitoring to improve patient outcome.

Nrf2 modulates immunosuppressive ability and cellular senescence of human umbilical cord mesenchymal stem cells

In the application of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) as clinical therapeutics, long term cells ex vivo expansion results in decline in their function. It has been widely concerned that cellular senescence is associated with UC-MSCs immunomodulatory ability. In this study, we evaluated the effects of consecutive passages on cellular senescence and the immunomodulatory abilities of UC-MSCs. Long term-cultured UC-MSCs showed decreased proliferation, senescence phenotypes and impaired immunosuppressive effects on PHA induced peripheral blood mononuclear cell (PBMC) proliferation. We found that Nrf2, a transcription factor that responds to oxidative stress, that showed decreased expression in long term-cultured UC-MSCs, and the further knock-down of Nrf2 in UC-MSCs induced premature senescence, decreased proliferation ability and immunosuppressive abilities. Furthermore, the protein expression of IDO-1 were decreased in response to the downregulation of Nrf2 in UC-MSCs, suggesting that Nrf2 regulates the immunosuppressive properties of UC-MSCs via Nrf2-mediated IDO-1 expression. In conclusion, our results demonstrate that Nrf2 plays a key role in the regulation of the immunosuppressive properties of UC-MSCs, and we suggest that these findings might provide a strategy to enhance the functionality of UC-MSCs for use in therapeutic applications.

Comparison of the Chemical Composition and Biological Activity of Mature and Immature Honey: An HPLC/QTOF/MS-Based Metabolomic Approach

Harvesting uncapped immature honey (IMH) followed by dehydration is a typical counterfeit honey production process, but the differences between IMH and capped mature honey (MH) have not been well described previously. In this study, MH and IMH from Apis mellifera colonies during the same rapeseed flower season were compared. MH was found to have lower water content, lower acidity, and higher fructose content. High-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry-based untargeted metabolomic analysis indicated that MH had a distinct metabolite composition to IMH. Targeted metabolomic analysis on 20 major polyphenolic constituents showed higher accumulation in MH. MH had greater bacteriostatic effect and stronger free radical scavenging effect. While both the honeys mitigated cell damage caused by H₂O₂, the effective dosage of IMH was higher and its inducing effect on the antioxidant gene expression was weaker. Overall, MH was shown to be of better quality than IMH not only because of its richer polyphenolic composition but also because of its stronger biological activity.

Mesenchymal stromal cells ameliorate acute lung injury induced by LPS mainly through stanniocalcin-2 mediating macrophage polarization

Background

Acute lung injury (ALI) is a devastating syndrome with no effective pharmacological therapies in the clinic. Mesenchymal stromal cells (MSCs) have been demonstrated to promote inflammation resolution and tissue repair in ALI. However, the specific mechanisms of this have not been clearly elucidated. Stanniocalcin-2 (STC2) is a stress-responsive protein that has anti-oxidative properties. Our previous study found that STC2 is a highly expressed stanniocalcin in MSCs, which may be involved in immunomodulatory activities. However, the role of STC2 in MSCs to resolve ALI has never been elucidated.

Methods

Specific shRNA was used to downregulate STC2 in MSCs. We detected ROS, cell apoptosis, and paracrine factors changes in MSCs. STC2-associated antioxidant genes were also investigated by Co-immunoprecipitation (Co-IP) and immunofluorescence. Macrophage (THP1 cells) phenotype transitions were measured by flow cytometry after coculturing with MSCs in vitro. Then, we used MSCs to treat LPS-induced ALI in mice, and assessed injury scores inflammation, and antioxidant activities in the lungs of the mice. Alveolar macrophage (AM) phenotypes and CFSE-labeled MSC apoptosis in collected bronchoalveolar fluids (BALF) were also analyzed by flow cytometry.

Results

After the STC2 knockdown, MSCs increased ROS generation and cell apoptosis after PX12 pretreatment. The antioxidant protein Nrf2 was colocalized with STC2 in the nucleus. A lack of STC2 expression in MSCs produced less interleukin 10 (IL10) and blunted macrophage polarization in THP1 cells. Furthermore, in the murine LPS-induced ALI model, the STC2 knockdown counteracted the inflammatory resolution and antioxidative effect of MSCs in the lungs. MSC^shSTC2-treated mice had a higher lung injury score than the controls, which may be attributed to diminished AM polarization and increased apoptosis of MSCs in vivo.

Conclusions

Collectively, these results suggested that STC2 is essential to the anti-oxidative and anti-inflammation properties of MSCs and could prove to be crucial for stem cell therapies for ALI.

Enhanced Therapeutic Potential of the Secretome Released from Adipose-Derived Stem Cells by PGC-1α-Driven Upregulation of Mitochondrial Proliferation

Peroxisome proliferator activated receptor λ coactivator 1α (PGC-1α) is a potent regulator of mitochondrial biogenesis and energy metabolism. In this study, we investigated the therapeutic potential of the secretome released from the adipose-derived stem cells (ASCs) transfected with PGC-1α (PGC-secretome). We first generated PGC-1α-overexpressing ASCs by transfecting ASCs with the plasmids harboring the gene encoding PGC-1α. Secretory materials released from PGC-1α-overexpressing ASCs were collected and their therapeutic potential was determined using in vitro (thioacetamide (TAA)-treated AML12 cells) and in vivo (70% partial hepatectomized mice) models of liver injury. In the TAA-treated AML12 cells, the PGC-secretome significantly increased cell viability, promoted expression of proliferation-related markers, such as PCNA and p-STAT, and significantly reduced the levels of reactive oxygen species (ROS). In the mice, PGC-secretome injections significantly increased liver tissue expression of proliferation-related markers more than normal secretome injections did (p < 0.05). We demonstrated that the PGC-secretome does not only have higher antioxidant and anti-inflammatory properties, but also has the potential of significantly enhancing liver regeneration in both in vivo and in vitro models of liver injury. Thus, reinforcing the mitochondrial antioxidant potential by transfecting ASCs with PGC-1α could be one of the effective strategies to enhance the therapeutic potential of ASCs.

Nrf2: Redox and Metabolic Regulator of Stem Cell State and Function

Nuclear factor erythroid 2-related factor 2 (Nrf2) is ubiquitously expressed in most eukaryotic cells and functions to induce a broad range of cellular defenses against exogenous and endogenous stresses, including oxidants, xenobiotics, and excessive nutrient/metabolite supply. Because the production and fate of stem cells are often modulated by cellular redox and metabolic homeostasis, important roles of Nrf2 have emerged in the regulation of stem cell quiescence, survival, self-renewal, proliferation, senescence, and differentiation. In a rapidly advancing field, this review summarizes Nrf2 signaling in the context of stem cell state and function and provides a rationale for Nrf2 as a therapeutic target in stem cell-based regenerative medicine.

Nrf2 Overexpression for the Protective Effect of Skin-Derived Precursors against UV-Induced Damage: Evidence from a Three-Dimensional Skin Model

Background

Skin photodamage is associated with ultraviolet- (UV-) induced reactive oxygen species (ROS) overproduction and nuclear factor erythroid 2-related factor 2 (Nrf2) inactivation. In our previous study, skin-derived precursors (SKPs) were shown to ameliorate a UV-induced damage in mice, probably through Nrf2 activation and ROS scavenging.

Objective

To clarify the mechanism underlying the photoprotective effect of SKPs against UV-induced damage in a three-dimensional (3D) skin model.

Methods

The Nrf2 gene in SKPs was modified using lentiviral infection, and 3D skin models were reconstructed with keratinocytes and fibroblasts on the basis of type I collagen. Subsequently, these models were divided into the following six groups: normal, model, overexpressed, control, silenced, and negative control groups. Prior to irradiation, respective SKPs were injected into the last four groups. Next, all groups except the normal group were exposed to UVA+UVB. Lastly, the pathological and molecular-biological techniques were employed to determine the parameters. Additionally, LY294002, a PI3K inhibitor, was used to investigate the roles of PI3K/Akt and Nrf2/hemeoxygenase-1 (HO-1) in SKP photoprotection.

Results

Normal 3D skin models appeared as milky-white analogs with a clear, well-arranged histological structure. After the skin was exposed to irradiation, it exhibited cell swelling and a disorganized structure and developed nuclear condensation with numerous apoptotic cells. The expressions of cellular protective genes and Nrf2/HO-1/PI3K/Akt proteins remarkably decreased, which were accompanied by increased oxidative stress and decreased antioxidants (P < 0.05). However, these phenomena were reversed by nrf2-overexpressing SKPs. The 3D skin in the overexpressed group showed mild swelling, neatly arranged cells, and few apoptotic cells. Cellular protective genes and Nrf2/HO-1/PI3K/Akt proteins were highly expressed, and the oxidative biomarkers were remarkably ameliorated (P < 0.05). Nevertheless, the expression of these proteins decreased after LY294002 pretreatment regardless of SKP treatment or not. Meanwhile, there were increases in both UV-induced apoptotic cells and ROS level accompanied with SOD and GPX decrease in the presence of LY294002.

Conclusions

Evidence from the 3D skin model demonstrates that the protection of SKPs against UV-mediated damage is primarily via the PI3K/Akt-mediated activation of the Nrf2/HO-1 pathway, indicating that SKPs may be a promising candidate for the treatment of photodermatoses.

A revealing review of mesenchymal stem cells therapy, clinical perspectives and Modification strategies

Multipotent mesenchymal stem cells (MSCs) have been considerably inspected as effective tool for cell-based therapy of inflammatory, immune-mediated, and degenerative diseases, attributed to their immunomodulatory, immunosuppressive, and regenerative potentials. In the present review, we focus on recent research findings of the clinical applications and therapeutic potential of this cell type, MSCs' mechanisms of therapy, strategies to improve their therapeutic potentials such as manipulations and preconditioning, and potential/unexpected risks which should be considered as a prerequisite step before clinical use. The potential risks would probably include undesirable immune responses, tumor formation and the transmission of incidental agents. Then, we also review some of the milestones in the field, briefly discuss challenges and highlight the new guideline suggested for future directions and perspectives.

Fibroblast growth factor 21 Ameliorates diabetes-induced endothelial dysfunction in mouse aorta via activation of the CaMKK2/AMPKα signaling pathway

Endothelial dysfunction initiates and exacerbates hypertension, atherosclerosis and other cardiovascular complications in diabetic mellitus. FGF21 is a hormone that mediates a number of beneficial effects relevant to metabolic disorders and their associated complications. Nevertheless, it remains unclear as to whether FGF21 ameliorates endothelial dysfunction. Therefore, we investigated the effect of FGF21 on endothelial function in both type 1 and type 2 diabetes. We found that FGF21 reduced hyperglycemia and ameliorated insulin resistance in type 2 diabetic mice, an effect that was totally lost in type 1 diabetic mice. However, FGF21 activated AMPKα, suppressing oxidative stress and enhancing endothelium-dependent vasorelaxation of aorta in both types, suggesting a mechanism that is independent of its glucose-lowering and insulin-sensitizing effects. In vitro, we identified a direct action of FGF21 on endothelial cells of the aorta, in which it bounds to FGF receptors to alleviate impaired endothelial function challenged with high glucose. Furthermore, the CaMKK2-AMPKα signaling pathway was activated to suppress oxidative stress. Apart from its anti-oxidative capacity, FGF21 activated eNOS to dilate the aorta via CaMKK2/AMPKα activation. Our data suggest expanded potential uses of FGF21 for the treatment of vascular diseases in diabetes.