Nrf2 Expression Research Articles

Melatonin Improves Oxidative Stress Injury in Retinopathy of Prematurity by Targeting miR-23a-3p/Nrf2

Purpose Melatonin has promising protective effects for retinopathy. However, its roles in retinopathy of prematurity (ROP) and the underlying mechanisms remain unknown. We aimed to explore its roles and mechanisms in a ROP model. Methods Hematoxylin and eosin staining were used to observe the morphology of the retina. Immunofluorescence was used to detect positive (Nrf2+ and VEGF+) cells. Immunohistochemistry was used to detect the level of nuclear expression of PCNA in retinal tissue. Transmission electron microscope (TEM) was used to observe the morphology and structure of pigment cells. qRT-PCR was used to assay the expression of miR-23a-3p, Nrf2, and HO-1. Western blotting was used to detect the expression of Nrf2, HO-1, β-actin, and Lamin B1. Results Melatonin or miR-23a-3p antagomir treatment could ameliorate the Oxygen-induced pathological changes, increased the expression of Nrf2 and HO-1, SOD, and GSH-Px, and decreased the expression of VEGF, miR-23a-3p, MDA and the apoptosis in the ROP model. Further target prediction and luciferase reporter assays confirmed the targeted binding relationship between miR-23a-3p and Nrf2. Conclusion Our study showed that melatonin could ameliorate H2O2-induced apoptosis and oxidative stress injury in RGC cells by mediating miR-23a-3p/Nrf2 signaling pathway, thereby improving retinal degeneration.

Different mechanisms guide the antinociceptive effect of bone marrow-mononuclear cells and bone marrow-mesenchymal stem/stromal cells in trigeminal neuralgia

AimsTrigeminal neuralgia (TN) is a type of chronic orofacial pain evoked by trivial stimuli that manifests as episodes of excruciating and sudden, recurrent paroxysmal pain. Most patients are refractory to pharmacological therapy used for the treatment of TN. Mononuclear cells (MNC) and mesenchymal stem/stromal cells (MSC) have shown therapeutic potential in painful neuropathies, but their mechanism of action is not fully understood. The present work aimed to investigate the antinociceptive effect and mechanism of action of MNC and MSC in experimental TN. Materials and methodsMice submitted to the chronic constriction injury of the infraorbital nerve (CCI-ION) mouse model of TN received a single intravenous injection of saline, MNC, or MSC (1 × 106 cells/mouse). The effect of the treatments on the behavioral signs of painful neuropathy, morphological aspects of the infraorbital nerve, and inflammatory and oxidative stress markers in the infraorbital nerve were assessed. Key findingsMNC and MSC improved behavioral painful neuropathy, activated key cell signaling antioxidant pathways by increasing Nrf2 expression, and reduced the proinflammatory cytokines IL-1β and TNF-α. However, treatment with MSC, but not MNC, was associated with a sustained increase of IL-10 and with the re-establishment of the morphometric pattern of the infraorbital nerve, indicating a difference in the mechanism of action between MNC and MSC. In line with this result, in IL-10 knockout mice, MSC transplantation did not induce an antinociceptive effect. SignificanceImportantly, these data suggest an IL-10-induced disease-modifying profile related to MSC treatment and reinforce cell therapy's potential in treating trigeminal neuralgia.

Nrf2/ASPM axis regulated vasculogenic mimicry formation in hepatocellular carcinoma under hypoxia.

Hypoxic microenvironment is a common feature of most solid tumors including hepatocellular carcinoma (HCC). Vasculogenic mimicry (VM) formation by tumor cells could provide blood supply to tumor cells under hypoxia. NFE2 like basic leucine zipper (bZIP) transcription factor 2 (Nrf2), a regulator of cellular homeostasis, may promote tumor progression in the hypoxic conditions. However, the role and regulatory mechanisms of Nrf2 in HCC are not fully elucidated. Nrf2 and assembly factor for spindle microtubules (ASPM) expression modulations were conducted by lentiviral transfections. Western blot, immunofluorescence, ChIP-qPCR, dual-luciferase reporter gene assay, flow cytometry, RNA sequencing, multiple bioinformatics databases analysis, cell function assays in vitro, mouse model in vivo and human HCC tissues were employed to assess the effect of Nrf2/ASPM axis on HCC progression under hypoxia. Nrf2 and ASPM expression facilitated epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs) feature, and VM formation of HCC cells under hypoxia. Furthermore, Nrf2-regulated ASPM expression, via binding directly to the promoter region of ASPM and transcriptionally promoting ASPM expression. ASPM re-expression in Nrf2 knockdown cells or ASPM knockdown in Nrf2 overexpression cells reversed the cellular function caused by Nrf2. Meantime, retinol metabolism pathway was disrupted following abnormal ASPM expression. Nrf2/ASPM axis in murine models accelerated tumor growth and VM, corroborating in vitro findings. All-trans retinoic acid treatment reversed stemness and VM of HCC cells in vitro and in vivo. Clinically, Nrf2 and ASPM expressions were related to poor prognosis of HCC patients. Nrf2 drives EMT, CSCs characteristics and VM in HCC under hypoxia through the modulation of ASPM. Retinol metabolism pathway was dysregulated in HCC cells with ASPM overexpression. Nrf2/ASPM axis and related pathway provided potential therapeutic target for HCC.

Effect of Pterostilbene Regulating Nuclear Factor E2-Related Factor 2 on Apoptosis of Colon Cancer Cells in Vitro

Objective To investigate the effects of pterostilbene on human colon cancer LoVo cells and study the regulatory mechanism of nuclear factor E2-related factor 2 (Nrf2) in the process of pterostilbene acting on LoVo cells. Methods LoVo cells were treated with different concentrations (5,10,20,40,60,80,100 μmol/L) of pterostilbene.Cell viability,migration,invasion,and apoptosis were examined by CCK-8,scratch,Transwell,and TUNEL assays,respectively.The mitochondrial membrane potential was measured by the mitochondrial membrane potential assay kit with JC-1.The reactive oxygen species level was measured by 2',7'-dichlorofluorescein diacetate.The protein levels of Nrf2,phosphorylated Nrf2,heme oxygenase 1,and apoptotic proteins (Bcl2 and Bax) were determined by Western blotting.In addition,cell viability,Nrf2 expression,and apoptosis rate were determined after co-application of the Nrf2-specific agonist sulforaphane. Results Compared with the control group,40,60,80,100 μmol/L pterostilbene reduced the viability of LoVo cells (P=0.014,P<0.001,P<0.001,P<0.001).Pterostilbene at 5,10,20 μmol/L did not show effects on cell viability but inhibited cell migration (P=0.008,P<0.001,P<0.001) and invasion (all P<0.001).Pterostilbene at 40,60,80 μmol/L increased apoptosis (P=0.014,P<0.001,P<0.001),promoted mitochondrial membrane potential depolarization (P=0.026,P<0.001,P<0.001) and reactive oxygen species accumulation (all P<0.001),and down-regulated the expression of phosphorylated Nrf2 (P=0.030,P<0.001,P<0.001),heme oxygenase 1 (P=0.015,P<0.001,P<0.001),and Bcl2 (P=0.039,P<0.001,P<0.001) in LoVo cells.Pterostilbene at 60,80 μmol/L down-regulated Nrf2 expression (P=0.001,P<0.001) and up-regulated Bax expression (both P<0.001).The application of sulforaphane reversed the effects of pterostilbene on cell viability (P<0.001),apoptosis (P<0.001),and Nrf2 expression (P=0.022). Conclusion Pterostilbene is a compound that can effectively inhibit colon cancer cells by inhibiting the Nrf2 pathway.

Retinal Penetrating Adeno-Associated Virus.

The most common method of delivery of genes to the outer retina uses recombinant adeno-associated virus (AAV) injected into the subretinal space using a surgical procedure. In contrast, most drugs are delivered to the retina using an intravitreal approach in an office setting. The objective of the current study was to develop AAV vectors that can reach the outer retina via intravitreal injection. Recently, we described a molecular chaperone (Nuc1) that enhanced the penetration of small and large molecules, including AAV, into the retina. The Nuc1 amino acid sequence or a truncated version of Nuc1 (IKV) was genetically incorporated into an exposed loop of AAV2/9 VP1 protein. These novel recombinant AAV vectors expressing green fluorescent protein (GFP) or nuclear factor erythroid 2 p45-related factor 2 (Nrf2) were injected into the vitreous of C57Bl/6J or Nrf2 knockout mice, respectively. The amount of GFP expression or oxidative stress as measured by 8-Hydroxy-2'-deoxyguanosine staining in C57Bl/6J or Nrf2 knockout mice, respectively, was quantified. Incorporation of Nuc1 into AAV2/9 did not lead to significant expression of GFP in the murine retina. However, incorporation of IKV into AAV2/9 led to robust expression of GFP in photoreceptors and retinal pigment epithelium (RPE) via the intravitreal and subretinal routes of delivery. Furthermore, expression of Nrf2 using an IKV vector led to a reduction in oxidative stress in the retina of C57Bl/6J and Nrf2 knockout mice. We have developed a novel AAV vector that enables delivery of transgenes to the outer retina of mice, including photoreceptors and RPE following intravitreal injection.

The role of uncoupling protein 2 in experimental periodontitis-associated renal injury in rats.

This study aims to explore changes in uncoupling protein 2 (UCP2) in experimental periodontitis-associated renal injury induced by ligation and investigate the effect of UCP2 on renal injury induced by periodontitis. Twelve Wistar male rats were randomly divided into two groups: control and periodontitis groups. A periodontal model was built by ligating the maxillary first molars area with 0.2 mm orthodontic ligature wire. After 8 weeks, the intraoral condition of the rats was observed and periodontal clinical indices such as gingival bleeding index (BI), periodontal probing depth (PD), and tooth mobility (TM) were detected. The maxillary bone was scanned by Micro CT to observe the alveolar bone resorption. The tissue mineral density (TMD), bone mineral density (BMD), bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular bone separation (Tb.Sp) were recorded, and the distance from the enamel bone boundary to the alveolar crest (CEJ-ABC) of the maxillary first molar was measured. The oxidative stress indexes such as malondialdehyde, glutathione (GSH), and superoxide dismutase (SOD) were detected using frozen rat kidney tissue. The gene expression of UCP2, nuclear factor erythroid 2-related factor 2 (Nrf2), and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) was observed by quantitative real-time polymerase chain reaction (qRT-PCR) test. The gingival tissue of the rats was used for immunohistochemical staining to observe the expression of the UCP2 protein. The fixed rat kidney tissue was used for hematoxylin-eosin (HE), periodic acid-schiff (PAS), MitoSOX Red, JC-1, and immunohistochemical staining to observe the renal histopathology, the level of reactive oxygen species (ROS), the level of mitochondrial membrane potential, and the expression of UCP2, Nrf2, and PGC-1α protein. Rat serum was collected to detect renal function indices, namely, blood urea nitrogen (BUN), creatinine (Cre), and albumin (Alb). Compared with the control group, the periodontitis group showed red, swollen, and soft gingival tissue, with gingival probing bleeding, periodontal PD increased, tooth loosening, alveolar bone resorption, decreased TMD, BMD, BV/TV, and Tb.Th indices, and increased Tb.Sp index, CEJ-ABC, and gingival UCP2 protein expression. Compared with the control group, the levels of MDA and ROS in the kidney tissue of periodontitis rats and the gene and protein expression of UCP2 increased, and the levels of MMP, GSH, and SOD and the gene and protein expression of Nrf2 and PGC-1α decreased. Renal functional indices, namely, BUN, Cre, and Alb, were not significantly different between the two groups. UCP2 may play a role in renal injury induced by periodontitis through oxidative stress.

Protective Effects of Curcumin and its Analogues via the Nrf2 Pathway in Metabolic Syndrome.

Metabolic Syndrome (MetS) refers to a set of medical conditions including insulin resistance, central obesity, atherogenic dyslipidemia, and hypertension. Due to these dysregulations, if not treated, MetS could increase the risk of CVA, CVD, and diabetes. As described by WHO, CVD is the leading cause of mortality in the world which motivates researchers to investigate the management of its risk factors, especially MetS. It is reported that oxidative stress secondary to the abundant generation of free radicals oxygen species (ROS) and the ensuing altered redox status play an important role as a mediator in MetS. As a result, using new antioxidant agents with higher bioavailability has been proposed as an efficient treatment. Curcumin (a polyphenol of the diarylheptanoids class), which is used as a traditional medicine for various diseases including cardiovascular diseases and diabetes, is characterized by its antioxidant properties which, at least in part, are mediated via the activation of the Nrf2/ARE signaling pathway. Nrf2 is a transcription factor that plays a key role in regulating internal defense systems and increases antioxidant levels to decrease oxidative damage and cell apoptosis. Nrf2 expression and stability are enhanced by curcumin, leading to a higher rate of Nrf2 migration to the cell nucleus to regulate ARE gene expression, thus protecting cells against oxidative stress. In this article, we provide a comprehensive review of the molecular effect of curcumin and its derivatives via Nrf2 regulation in several conditions, such as diabetes, hypertension, dyslipidemia, and obesity.

Sulodexide protects endothelial cells against 4-hydroxynonenal-induced oxidative stress and glutathione-dependent redox imbalance by modulation of sestrin2/nuclear factor erythroid 2-related factor 2 pathway.

The lipid peroxidation product 4-hydroxynonenal (HNE) may be involved in vascular endothelial cell damage by induction of oxidative stress, apoptosis, and loss of redox homeostasis. There is evidence that stimulation of endothelial cells with 4-HNE induces the activation of the nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/Keap-1) pathway. Sestrin2 protein (SESN2) is one of the key regulators of Nrf2 and is involved in the cellular response to oxidative stress. However, the function of SESN2 in HNE-induced endothelial injury is not yet understood. Sulodexide (SDX) is a mixture of glycosaminoglycans used in clinical practice in the treatment of chronic venous and arterial diseases. While SDX has well-documented endothelial protective properties, little is known about its antioxidant effects. The aim of this study was to elucidate the molecular mechanisms activated by SDX in human umbilical endothelial cells (HUVECs) under HNE-induced oxidative stress. In this experimental model, we decided to evaluate the anti-apoptotic and antioxidant potential of SDX and its effect on the SESN2/Nrf2/GSH pathway. HUVECs were treated with 25 _M HNE or HNE combined with 0.5 LRU/mL SDX for 4 hours. Cell viability, apoptosis and intracellular reactive oxygen species (ROS) production were assessed by MTT assay and fluorescence microscopy. The expressions of Bax, cleaved caspase-3, Keap-1 and Nrf2 were determined by Western blot analysis. The intracellular concentrations of reduced glutathione (GSH) and oxidized glutathione (GSSG) were measured by colorimetric assay. SESN2, glutamate-cysteine ligase catalytic subunit (GCLc) and glutathione synthase (GSS) were assessed using ELISA. RT-qPCR was performed to detect Nrf2, GCLc and GSS mRNA levels. Transient Nrf2 silencing was obtained by short interfering RNA (siRNA). We have demonstrated that SDX can reduce the negative impact of HNE on HUVECs. SDX significantly protected HNE-treated HUVECs from apoptosis (p<0.001) and oxidative stress (p<0.001). SDX treatment significantly reduced Bax (p<0.05) and cleaved caspase-3 (p<0.01) expression. Co-administration of HNE and SDX increased GSH content (p<0.001) and GSH:GSSG ratio (p<0.001) as well as decreased SESN2 concentration (p<0.001) and Nrf2 (p<0.01), GCLc (p<0.05) and GSS (p<0.01) gene expression compared with the HNE group. Moreover, we revealed a negative correlation between SESN2 levels and GSH concentrations (p<0.001). Nrf2 silencing significantly decreased the effect of HNE and SDX on the induction of GCLc and GSS genes. SDX also significantly ameliorated the increase of nuclear Nrf2 in response to HNE (p<0.05). The results confirmed that SDX may protect against HNE-induced endothelial damage through its antioxidant effect and modulation of the SESN2/Nrf2/GSH signaling pathway.

Ultrafiltration of Angelicae Sinensis Radix and Astragali Radix inhibits ferroptosis and improves pulmonary fibrosis in rats by regulating Nrf2/xCT/GPX4 signaling pathway

This study aims to investigate the mechanism of ferroptosis mediated by the nuclear factor-E2-related factor 2(Nrf2)/solute carrier family 7 member 11(SLC7A11, also known as xCT)/glutathione peroxidase 4(GPX4) signaling pathway in radiationinduced pulmonary fibrosis and the intervention effect of Angelicae Sinensis Radix(ASR) and Astragali Radix(AR) ultrafiltration extract. Fifty Wistar rats were randomly divided into five groups, with 10 rats in each group. Except for the blank group without radiation, the rats in each group were anesthetized and subjected to a single local chest irradiation of 40 Gy X-rays once to establish a rat model of radiation-induced pulmonary fibrosis. After radiation, the rats in the intervention groups were orally administered with ASR-AR ultrafiltration extract at doses of 0. 12, 0. 24, and 0. 48 g·kg~(-1), respectively, once a day for 30 days. After 30 days of continuous administration, the levels of oxidative stress indicators superoxide dismutase(SOD) activity, reduced glutathione(GSH),malondialdehyde(MDA), and ferrous ion(Fe~(2+)) in lung tissues of each group were detected by colorimetry. Immunofluorescence was used to detect reactive oxygen species(ROS) fluorescence expression in lung tissues. Hematoxylin-eosin(HE) and Masson staining were performed to observe pathological changes in lung tissues. Immunohistochemistry and Western blot were used to detect the expression levels of Nrf2/xCT/GPX4 signaling pathway and fibrotic proteins in lung tissues. The results showed that compared with the results in the blank group, the levels of Fe~(2+) and MDA in the model group increased, while SOD activity and GSH levels decreased,and ROS levels increased. HE and Masson staining results showed that the structure of lung tissue was seriously damaged, the pulmonary interstitium was significantly proliferated, the alveoli collapsed and consolidated severely, and there were more inflammatory cell aggregates and collagen fiber deposits. Transmission electron microscopy showed that the degree of lung tissue damage in the model group was relatively high, with increased, smaller, and disorganized damaged mitochondria, irregular morphology, shallow matrix,most mitochondria ruptured and shortened, mildly expanded, some mitochondria with increased electron density of the matrix, partial mitochondrial outer membrane rupture, and characteristic changes of ferroptosis-specific mitochondria. Immunohistochemistry showed that the expression of transferrin receptor protein 1(TFR1) in lung tissues was significantly increased, while the expression of GPX4,ferritin heavy chain 1(FTH1), Nrf2, and xCT was significantly decreased. Western blot showed that the expression of α-smooth muscle actin(α-SMA) and collagen Ⅰ protein increased. Compared with the model group, the intervention group with ASR-AR ultrafiltration extract significantly improved lipid peroxidation and antioxidant-related indicators, decreased Fe~(2+) levels, alleviated fibrosis, and decreased the expression of TFR1, α-SMA, and collagen Ⅰ proteins in lung tissues, while increased the expression of GPX4, FTH1, Nrf2, and xCT proteins. In summary, ASR-AR ultrafiltration extract has an ameliorative effect on radiation-induced pulmonary fibrosis, and its mechanism may involve the inhibition of ferroptosis by regulating the Nrf2/xCT/GPX4 signaling pathway.

Network pharmacology and in vivo experimental studies reveal the protective effects of 6-hydroxygenistein against hypobaric hypoxia-induced brain injury

Hypobaric hypoxia-induced brain injury (HHBI) is a progressive neurodegenerative disease that has still not been effectively treated. There are several different mechanisms involved in HHBI. Among them, oxidative stress and inflammation response predominate. 6-hydroxygenistein (4′,5,6,7-tetrahydroxyisoflavone, 6-OHG) is a hydroxylated derivative of genistein with excellent antioxidant activity, however, the protective effects and underlying mechanisms against HHBI have not been clarified. In the present study, we aimed to explore the mechanisms of action of 6-OHG on HHBI using network pharmacology and experimental validation. Network pharmacology analysis revealed 186 candidate targets through the intersection of the targets of 6-OHG and related genes in HHBI, which were mainly enriched in oxidative stress and inflammation response. Moreover, key targets of 6-OHG against HHBI, namely Nrf2 and NF-κB, were screened and found to be closely related to oxidative stress and inflammation response. Subsequent in vivo experiments revealed that 6-OHG treatment attenuated oxidative stress and inflammation response, prevented energy disorder and apoptosis as well as maintained the BBB integrity in HHBI mice. In addition, 6-OHG administration up-regulated the expressions of Nrf2 and HO-1 and down-regulated the expressions of NF-κB and NLRP3, thereby inhibiting oxidative stress and inflammation response. Hence, the present study demonstrates that 6-OHG protects against HHBI by stimulating the Nrf2/HO-1 signaling pathway and suppressing the NF-κB/NLRP3 signaling pathway.

Pharmacological characterization of the antidiabetic drug metformin in atherosclerosis inhibition: A comprehensive insight.

Atherosclerosis (AS) is a progressive disease that interferes with blood flow, leading to cardiovascular complications such as hypertension, ischemic heart disease, ischemic stroke, and vascular ischemia. The progression of AS is correlated with inflammation, oxidative stress, and endothelial dysfunction. Various signaling pathways, like nuclear erythroid-related factor 2 (Nrf2) and Kruppel-like factor 2 (KLF2), are involved in the pathogenesis of AS. Nrf2 and KLF2 have anti-inflammatory and antioxidant properties. Thus, activation of these pathways may reduce the development of AS. Metformin, an insulin-sensitizing drug used in the management of type 2 diabetes mellitus (T2DM), increases the expression of Nrf2 and KLF2. AS is a common long-term macrovascular complication of T2DM. Thus, metformin, through its pleiotropic anti-inflammatory effect, may attenuate the development and progression of AS. Therefore, this review aims to investigate the possible role of metformin in AS concerning its effect on Nrf2 and KLF2 and inhibition of reactive oxygen species (ROS) formation. In addition to its antidiabetic effect, metformin can reduce cardiovascular morbidities and mortalities compared to other antidiabetic agents, even with similar blood glucose control by the Nrf2/KLF2 pathway activation. In conclusion, metformin is an effective therapeutic strategy against the development and progression of AS, mainly through activation of the KLF2/Nrf2 axis.

Nrf2-Mediated Antioxidant Response and Drug Efflux Transporters Upregulation as Possible Mechanisms of Resistance in Photodynamic Therapy of Cancers.

Photodynamic therapy (PDT) is a groundbreaking approach involving the induction of cytotoxic reactive oxygen species (ROS) within tumors through visible light activation of photosensitizers (PS) in the presence of molecular oxygen. This innovative therapy has demonstrated success in treating various cancers. While PDT proves highly effective in most solid tumors, there are indications that certain cancers exhibit resistance, and some initially responsive cancers may develop intrinsic or acquired resistance to PDT. The molecular mechanisms underlying this resistance are not fully understood. Recent evidence suggests that, akin to other traditional cancer treatments, the activation of survival pathways, such as the KEAP1/Nrf2 signaling pathway, is emerging as an important mechanism of post-PDT resistance in many cancers. This article explores the dual role of Nrf2, highlighting evidence linking aberrant Nrf2 expression to treatment resistance across a range of cancers. Additionally, it delves into the specific role of Nrf2 in the context of photodynamic therapy for cancers, emphasizing evidence that suggests Nrf2-mediated upregulation of antioxidant responses and induction of drug efflux transporters are potential mechanisms of resistance to PDT in diverse cancer types. Therefore, understanding the specific role(s) of Nrf2 in PDT resistance may pave the way for the development of more effective cancer treatments using PDT.

Yinxieling attenuates psoriasis in mice by regulating oxidative stress and lipid mediators to correct immune cell disorder through the NF-κB/Nrf2 signaling pathways

BackgroundPsoriasis is a chronic skin disease that causes inflammation over time due to immune cell-mediated inflammation, oxidative stress, and lipid mediator imbalance. This study was to investigate the impact of Yinxieling (YXL), a reliable Chinese medicine for the treatment of psoriasis vulgaris, on the redox balance and lipid mediators in mice with IMQ-induced psoriasis. MethodsDaily application of aqueous extract of YXL on IMQ-induced psoriasis-like mice, the efficacy and mechanism of YXL were evaluated by appearance symptoms, oxidative stress indicators, immune balance, and lipid metabolism indicators. ResultsThe results demonstrated that YXL significantly enhanced therapeutic efficacy in a psoriasis mouse model, markedly improving the PASl scores and cutaneous inflammation. Upon YXL treatment, lipid peroxidation levels were significantly reduced, while antioxidant levels correspondingly increased. Additionally, YXL modulated the metabolic enzymes associated with 2-AG, which led to a decrease in CB1 receptor expression and an increase in CB2 receptor expression. In terms of immune modulation, YXL treatment promoted the regulation of T cell populations by down-regulating Th1, Th17, and γδT cells, while up-regulating Th2 and Treg cells, thereby facilitating the formation of an anti-inflammatory state. Further analysis indicated that these regulatory effects were closely associated with the down-regulation of NF-kB expression and the up-regulation of Nrf2 expression. ConclusionIn conclusion, YXL reduces mice dermatitis by inhibiting oxidative stress, elevating endocannabinoid levels and balancing T cell populations in IMQ-induced psoriasis through the NF-κB and Nrf2 signaling pathways. Our results suggest its potential as a therapeutic option for psoriasis by targeting multiple pathways involved in the disease's development.

Effect of New Antidiabetics on Steatosis in Nerve Tissues and Nerve Conduction Velocity: Possible Role of Nerve Growth Factor (NGF)/Synaptophysin and Nrf2/HO-1 Pathways.

The current study aims to investigate the impact of the GLP1 analog (semaglutide) and SGLT2 inhibitor (dapagliflozin) on nerve functions, morphology, and the underlying mechanisms involving nerve growth factor (NGF)/synaptophysin and Nrf2/HO-1 pathways in obese rats. Forty male Sprague Dawley rats, aged six to eight weeks, were classified into five groups; normal group (high-fat diet {HFD} for 12 weeks, metformin group (HFD for 12 weeks + metformin in last four weeks), dapagliflozin group (HFD for 12 weeks +dapagliflozin in last four weeks, semaglutide group (HFD for 12 weeks + semaglutide in last four weeks). At the end of the experiment, the sciatic nerve was collected for nerve conduction study, oxidative stress marker (malondialdehyde, i.e., MDA), real-time polymerase chain reaction (PCR) study (for HO-1 and Nrf2), oil red O staining, electron microscopic examination and immunohistochemistry for NGF and synaptophysin. The HFD group showed a significant rise in blood glucose, serum lipids, homeostatic model assessment (HOMA) index, lipid deposition in nerve tissues, and lipid peroxidation (MDA) in nerve tissues with significant attenuation in nerve conduction velocity (NCV), the expression of Nrf2 and HO-1 genes and significant attenuation in area stained with NGF and synaptophysin. On the other hand, pretreatment with either dapagliflozin or semaglutide led to considerable enhancement in the deteriorated serum and nerve tissue parameters and reversed the pathological changes. New antidiabetic drugs like SGLT2 inhibitors (more powerful) and GLP1 analog might have neuroprotective beneficial effects besides controlling the glycemic state in obese rats. This effect may result from reduced oxidative stress and increased Nrf2 levels, HO-1, synaptophysin, and NGF in the nerve tissues of obese rats.

Empagliflozin mitigates methotrexate-induced nephrotoxicity in male albino rats: insights on the crosstalk of AMPK/Nrf2 signaling pathway

BackgroundThe anti-diabetic drug, empagliflozin (EMPA), has many pleiotropic actions and is challenged recently to possess renoprotective properties. This renoprotective potential is proposed to be mediated via the activation of AMP-activated protein kinase (AMPK)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. This research investigated the renoprotective potential and the mechanistic pathway of EMPA against methotrexate (MTX)-induced nephrotoxicity and evaluated the role of AMPK by utilizing an AMPK inhibitor, dorsomorphin (Dorso).MethodsThirty male Wistar rats, weighing 180–200 g, were divided equally into five groups. Group I represented the control group. Nephrotoxicity was induced in the remaining rats through the administration of a single intraperitoneal injection of MTX (20 mg/kg). Rats were then randomly assigned to: Group 2 (received MTX injection only); Group 3 (received MTX and EMPA 30 mg/kg/day); Group 4 (received MTX and Dorso 0.2 mg/kg/day), Group 5 (received MTX, Dorso, EMPA). After one week, blood samples were collected, the rats were euthanized, and renal tissues were harvested for biochemical and histomorphometric assessments.ResultsMTX produced a significant rise in serum creatinine and tissue MDA levels; an increase in BAX, p53, cytochrome-c expression; a reduction in Bcl2 level; and disruption of renal microarchitecture. In contrast, EMPA therapy in group 3, resulted in a significant improvement of all these parameters, correlated with significant increase in AMPK phosphorylation and Nrf2 expression. Importantly, the co-administration of Dorso, in group 5, prevented EMPA’s beneficial effects.ConclusionEMPA has a potential protective effect against MTX-induced toxicity through the activation of the AMPK/Nrf2 signaling pathway.

Ganweikang extract protects hepatocytes from oxidative injury by activating Nrf2/HO-1 and MAPKs pathways

Ganweikang tablet (GWK) is a traditional Chinese prescription and has been clinically used in treating liver diseases for decades. Although GWK has been shown to exert potential therapeutic effect for hepatotoxicity protection, the underlying biological mechanisms are still not well clarified. In the present study, the compositional analysis of GWK was performed by HPLC analysis, and the hepato-protective effects of GWK were assessed in H2O2-stimulated acute oxidative injured HL-7702 hepatocytes in vitro. As a result, 7 components in GWK were quantified to be 0.06 ± 0.01% (calycosin), 0.46 ± 0.02% (calycosin-7-glucoside), 0.13 ± 0.01% (liquiritin), 0.17 ± 0.02% (glycyrrhizic acid), 0.45 ± 0.02% (forsythoside A), 0.07 ± 0.01% (5-O-methylvisammioside) and 0.45 ± 0.02% (forsythin), respectively. Furthermore, GWK (100, 200 and 400 μg/mL, 24 h) dose-dependently alleviated HL-7702 hepatocytes from H2O2 (200 μM, 2 h)-induced cell apoptosis by decreasing the intracellular reactive oxygen species (ROS) generation and malondialdehyde (MDA) level, as well as the cellular aminotransferases (ALT and AST) activities. GWK increased the expressions of HO-1, NQO1 and Nrf2, while suppressing the expression of KEAP1 in H2O2−stimulated HL-7702 cells. A specific Nrf2 inhibitor, ML385, was further employed to investigate the regulation of Nrf2 in HL-7702 cells stimulated by H2O2. In addition, the activation of MAPKs (JUN, ERK and p38) was simultaneously detected in H2O2−stimulated HL-7702 cells. In conclusion, GWK exerted potential therapeutic effect to protect hepatocytes from acute oxidative injury through activating the Nrf2/HO-1 and MAPKs pathways.

Ellagic acid supplementation ameliorates cisplatin-induced liver injury in mice by inhibiting the NF-κB pathway and activating the Nrf2/HO-1 pathway

Cisplatin (cis-diaminodichloroplatinum II, CDDP), an essential chemotherapeutic agent, can cause potential hepatotoxicity, but the underlying molecular mechanisms remain unclear. In this study, the protective effects of ellagic acid (EA) on CDDP exposure-induced hepatotoxicity and the underlying molecular mechanisms were investigated in a mouse model. Mice were randomly divided into control, CDDP model, EA100 (i.e., 100 mg/kg/day), and CDDP plus 25, 50, or 100 mg/kg/day EA groups. Mice in all the CDDP-treated groups were intraperitoneally injected with 20 mg/kg/day CDDP for two days. For all EA cotreatments, the mice were orally administered EA for seven days. Our results revealed that CDDP treatment resulted in liver dysfunction, oxidative stress, and caspase activation, which were effectively attenuated by EA cotreatment in a dose-dependent manner. Furthermore, EA supplementation significantly downregulated the CDDP exposure-induced protein and mRNA expression of NF-κB, IL-1β, TNF-α, and IL-6 but further upregulated the protein and mRNA expression of Nrf2 and HO-1. Molecular docking analysis revealed strong interactions between EA and the NF-κB or Keap1 proteins. In conclusion, our results revealed that EA supplementation could ameliorate CDDP-induced liver toxicity in mice by activating the Nrf2/HO-1 signaling pathway and inhibiting the NF-kB signaling pathway.

The activity of the Nrf2/Keap1 pathway regulates A549 Non-small-cell Lung Cancer (NSCLC) cells motility through RhoAROCK1 pathway

Purpose: It is observed that Nrf2 transcription factors initiate the production of proteins that play a role in regulating tumor growth, the study aims to discover whether Nrf2 will regulate cell motility in A549 NSCLC cells. The ROCK-RhoA pathway is a significant contributor to cell growth and migration, which can relate to cell motility. There might be a connection between Nrf2 and ROCK-RhoA pathway, the study aims to see whether Nrf2 regulates A549 NSCLC cell motility through ROCK-RhoA pathway. Method: The study will use wound healing assay to visualize cell motility, comparison is made between positive control group(A549 cells treated with brusatol) and negative control group(A549 cells not treated with brusatol), respectively representing the expression level of Nrf2 where it is inhibited or normal. The pathway by which Nrf2 regulates cell motility is studied by western blotting and chemiluminescence. Possible result: There are four main possible results: (1), Nrf2 regulates cell motility in A549 NSCLC cells, the pathway involved in this regulation is ROCK-RhoA pathway. (2), Nrf2 regulates cell motility in A549 cells, however, the pathway involved in this regulation requires further studies to decide. (3), There is no obvious correlation between Nrf2 expression level and cell motility, the inhibition of Nrf2 results in change of expression level of the ROCK-RhoA pathway, however. (4), There is no obvious correlation between Nrf2 expression level and cell motility, ROCK-RhoA pathway is not significantly affected by inhibition of Nrf2 expression, further studies are needed to decide pathways involved. Conclusion: The result of this study provides valuable insights for studying the role of Nrf2 in regulating cell motility and the pathway in the process. It would improve understanding of Nrf2 transcription factor, and how it interacts with pathways to carry out regulation of cell motility. The study also provides future possibilities in terms of cancer treatment and development of gene-based medicine.

Chelerythrine ameliorates Aspergillus fumigatus keratitis through suppressing the LOX-1/p38 MAPK signaling pathway

PurposeAspergillus fumigatus (A. fumigatus) keratitis is a type of infectious corneal disease that significantly impairs vision. The objective of this study is to evaluate the therapeutic potential of chelerythrine (CHE) on A. fumigatus keratitis. MethodsThe antifungal activity of CHE was assessed through various tests including the minimum inhibitory concentration test, scanning electron microscopy, transmission electron microscopy, propidium iodide uptake test and plate count. Neutrophil infiltration and activity were assessed using immunofluorescence staining and the myeloperoxidase test. RT-PCR, western blotting assay, and ELISA were performed to measure the expression levels of proinflammatory cytokines (IL-1β and IL-6), NF-E2-related factor (Nrf2), heme oxygenase-1 (HO-1), and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), as well as to determine the ratio of phosphorylated-p38 (p-p38) mitogen-activated protein kinase (MAPK) to p38 MAPK. ResultsIn vitro, CHE inhibited the growth of A. fumigatus conidia, reduced fungal hyphae survival, and prevented fungal biofilm formation. In vivo, CHE reduced the severity of A. fumigatus keratitis and exhibited an excellent anti-inflammatory effect by blocking neutrophil infiltration. Furthermore, CHE decreased the expression levels of proinflammatory cytokines and LOX-1 at both mRNA and protein levels, while also decreasing the p-p38 MAPK/p38 MAPK ratio. Additionally, CHE increased the expression levels of Nrf2 and HO-1. ConclusionCHE provides protection against A. fumigatus keratitis through multiple mechanisms, including reducing fungal survival, inducing anti-inflammatory effects, enhancing Nrf2 and HO-1 expression, and suppressing the signaling pathway of LOX-1/p38 MAPK.

Characterization and molecular docking of tetrapeptides with cellular antioxidant and ACE inhibitory properties from cricket (Acheta domesticus) protein hydrolysate

Wide-ranging bioactivities of enzymatically digested insect protein to produce peptides have been targeted for functional food development. In this study, fractionated peptides obtained from cricket (Acheta domesticus) protein hydrolysate by alcalase digestion were identified and evaluated for their bioactivities. Peptide fractions F44, F45, and F46, isolated through size exclusion chromatography, demonstrated strong cytoprotective effects on SH-SY5Y and HepG2 cells exposed to H2O2. This was evidenced by a 2-fold decrease in reactive oxygen species (ROS) accumulation in the cells and a 3-fold upregulation of genes encoding antioxidant enzymes. The F45 peptide fractions also showed chemical antioxidant activities ranging from approximately 290 to 393 mg trolox/g peptide, measured by DPPH, ABTS, and FRAP assays. Furthermore, F45 demonstrated the highest angiotensin-converting enzyme I (ACE) inhibitory activity, 57.93 %. F45 induced higher levels of Nrf2, SOD1, SOD2, CAT, GSR, and GPx4 gene expression in SH-SY5Y and HepG2 cells compared to cells treated with H2O2 and no peptides (p < 0.05). Cells treated with H2O2 and F45 exhibited significantly increased antioxidant enzyme activity, including SOD, CAT, GSR, and GPx (p < 0.05). The F45B fraction from F45 was sequenced to obtain FVEG and FYDQ tetrapeptides. Molecular docking analysis revealed their high binding affinity to cellular antioxidant enzymes (SOD, CAT, GSR, GPx1, and GPx4), an antioxidant-related protein (Keap1), and ACE. These results suggest that the novel tetrapeptides from Acheta domesticus demonstrate important biological activities, establishing them as significant cellular antioxidant activities and a potential source of antihypertensive peptides.