TXNIP mediated by EZH2 regulated osteogenic differentiation in hBmscs and MC3T3-E1 cells through the modulation of oxidative stress and PI3K/AKT/Nrf2 pathway.

BACKGROUND: Previous research has identified a significant role of Thioredoxin-interacting protein (TXNIP) in bone loss. The purpose of this investigation was to assess the role and the underlying molecular mechanisms of TXNIP in the osteogenic differentiation of human bone marrow stromal cells (hBMSCs) and pre-osteoblast MC3T3-E1 cells. METHODS: Human bone marrow stem cells (hBMSCs) and MC3T3-E1 cells were used to induce osteogenic differentiation. The expression of genes and proteins was assessed using RT-qPCR and western blot, respectively. ChIP assay was used to validate the interaction between genes. The osteogenic differentiation ability of cells was reflected using ALP staining and detection of ALP activity. The mineralization ability of cells was assessed using ARS staining. DCFCA staining was employed to evaluate the intracellular ROS level. RESULTS: Initially, downregulation of TXNIP and upregulation of EZH2 were observed during osteogenesis in hBMSCs and MC3T3-E1 cells. Additionally, it was discovered that EZH2 negatively regulates TXNIP expression in these cells. Furthermore, experiments indicated that the knockdown of TXNIP stimulated the activation of the PI3K/AKT/Nrf2 signaling pathway in hBMSCs and MC3T3- E1 cells, thus inhibiting the production of reactive oxygen species (ROS). Further functional experiments revealed that overexpression of TXNIP inhibited the osteogenic differentiation in hBMSCs and MC3T3-E1 cells by enhancing ROS produc-tion. On the other hand, knockdown of TXNIP promoted the osteogenic differentiation capacity of hBMSCs and MC3T3-E1 cells through the activation of the PI3K/AKT/Nrf2 pathway. CONCLUSION: In conclusion, this study demonstrated that TXNIP expression, under the regulation of EZH2, plays a crucial role in the osteogenic differentiation of hBMSCs and MC3T3-E1 cells by regulating ROS production and the PI3K/AKT/Nrf2 pathway.

Songorine inhibits oxidative stress-related inflammation through PI3K/AKT/NRF2 signaling pathway to alleviate lipopolysaccharide-induced septic acute lung injury.

OBJECTIVE: The present study aimed to investigate the protective action and mechanism of songorine on sepsis-induced acute lung injury (ALI). METHODS: The sepsis-induced ALI mouse and cell models were established by lipopolysaccharide (LPS) induction. Lung injury was assayed by hematoxylin and eosin staining, lung injury score, and lung wet-to-dry (W/D) weight ratio. Apoptosis in lung tissues was evaluated by TUNEL assay, and the expression of apoptosis-related markers (Bcl2, Bax, and caspase-3) was measured by western blotting. Levels of pro-inflammatory factors and oxidative stress markers in the bronchoalveolar lavage fluid (BALF) of mice were measured by ELISA and RT-qPCR. The expression of PI3K/AKT/NRF2 pathway-related proteins was analyzed by western blotting. RESULTS: Songorine treatment at 40 mg/kg mitigated sepsis-induced ALI, characterized by improved histopathology, lung injury score, and lung W/D weight ratio (p < 0.05). Moreover, songorine markedly attenuated sepsis-induced apoptosis in lung tissues; this was evidenced by an increase in Bcl2 levels and a decrease in Bax and caspase-3 levels (p < 0.01). Also, songorine reduced levels of proinflammatory cytokines (TNF-α, IL-6, IL-1ß and MPO) and oxidative stress regulators (SOD and GSH) in the BALF of LPS-induced sepsis mice and RAW264.7 cells (p < 0.05). In addition, songorine upregulated the PI3K/AKT/NRF2 pathway-related proteins in LPS-induced sepsis mice and RAW264.7 cells (p < 0.05). Furthermore, LY294002 (a PI3K inhibitor) treatment reversed the protective effect of songorine on sepsis-induced ALI. CONCLUSION: Songorine inhibits oxidative stress-related inflammation in sepsis-induced ALI via the activation of the PI3K/AKT/NRF2 signaling pathway.

Dexmedetomidine alleviates hepatic ischaemia-reperfusion injury via the PI3K/AKT/Nrf2-NLRP3 pathway.

Hepatic ischaemia-reperfusion (I/R) injury constitutes a tough difficulty in liver surgery. Dexmedetomidine (Dex) plays a protective role in I/R injury. This study investigated protective mechanism of Dex in hepatic I/R injury. The human hepatocyte line L02 received hypoxia/reoxygenation (H/R) treatment to stimulate cell model of hepatic I/R. The levels of pyroptosis proteins and inflammatory factors were detected. Functional rescue experiments were performed to confirm the effects of miR-494 and JUND on hepatic I/R injury. The levels of JUND, PI3K/p-PI3K, AKT/p-AKT, Nrf2, and NLRP3 activation were detected. The rat model of hepatic I/R injury was established to confirm the effect of Dex in vivo. Dex reduced pyroptosis and inflammation in H/R cells. Dex increased miR-494 expression, and miR-494 targeted JUND. miR-494 inhibition or JUND upregulation reversed the protective effect of Dex. Dex repressed NLRP3 inflammasome by activating the PI3K/AKT/Nrf2 pathway. In vivo experiments confirmed the protective effect of Dex on hepatic I/R injury. Overall, Dex repressed NLRP3 inflammasome and alleviated hepatic I/R injury via the miR-494/JUND/PI3K/AKT/Nrf2 axis.

Resveratrol Attenuates the Cytotoxicity Induced by Amyloid-ß1-42 in PC12 Cells by Upregulating Heme Oxygenase-1 via the PI3K/Akt/Nrf2 Pathway.

Oxidative stress and cytotoxic damage induced by amyloid beta (Aß) have been considered pivotal in the pathogenesis of Alzheimer's disease (AD) and may represent a target for treatment. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway elicits a survival signal to protect against multiple injuries, and the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), a downstream target of the PI3K/Akt pathway, can bind to HO-1. Resveratrol, a natural polyphenol derived from grapes, has been widely reported to have diverse antioxidative effects against AD, but the mechanisms have not been fully elucidated. The present study aims to investigate the effects of resveratrol on Aß1-42-induced cytotoxicity in PC12 cells and to explore the potential mechanisms of these effects. PC12 cells were cultured and treated with Aß1-42. Oxidative stress was assessed by measuring malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels. After treating with resveratrol at different concentrations (0, 10, 20, 40 µM) and for different durations (24, 48, 72 h), the generation of MDA, GSH, and SOD were detected; cell viability was assessed by MTT assay. The production of reactive oxygen species (ROS) was determined using an ROS Assay Kit. Western blotting was used to detect the protein expression. Our studies showed that pretreatment with resveratrol could reduce Aß1-42-induced oxidative stress in PC12 cells by inhibiting the generation of MDA and ROS and increasing the production of SOD and GSH. Resveratrol markedly attenuated the Aß1-42-induced loss in cell viability in PC12 cells in both a dose- and time-dependent manner. More importantly, resveratrol stimulated the activation of HO-1, Nrf2, PI3K, and phosphorylated Akt. Notably, the neuroprotective effects of resveratrol were eliminated by the HO-1 inhibitor zinc protoporphyrin IX (ZnPP), Nrf2 small interfering RNA (siRNA), and the PI3K/Akt inhibitor LY294002. Taken together, the findings suggest that the cytoprotection of resveratrol against the cytotoxicity induced by Aß1-42 in PC12 cells is through the upregulation of HO-1 expression via the activation of the PI3K/AKT/Nrf2 intracellular signaling pathway, which might provide novel insights for understanding the mechanism of the neuroprotective effect of resveratrol as an anti-AD drug.

Protective effects of triptolide against oxidative stress in retinal pigment epithelium cells via the PI3K/AKT/Nrf2 pathway: a network pharmacological method and experimental validation.

PURPOSE: Among aging adults, age-related macular degeneration (AMD), is a prevalent cause of blindness. Nevertheless, its progression may be halted by antioxidation in retinal pigment epithelium (RPE). The primary effective constituent of Tripterygium wilfordii Hook. F., triptolide (TP), has demonstrated anti-inflammatory, antiproliferative, and antioxidant properties. The mechanics of the protective effect of triptolide against the oxidative damage in retinal pigment epithelial (RPE) were assessed in this study. METHODS: ARPE-19 cells were pretreated with TP, and then exposed to sodium iodate (SI). First, cell viability was assessed using CCK-8. Subsequently, we measured indicators for cell oxidation including reactive oxygen species (ROS), catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA). Then, we used network pharmacological analysis and molecular docking to explore the signaling pathway of TP. Last, we used western blot, ELISA, and immunofluorescence assays to clarify the potential mechanistic pathways. RESULTS: The network pharmacology data suggested that TP may inhibit AMD by regulating the PI3K/Akt signaling pathway. Experimental results showed that the potential mechanism is that it regulates the PI3K/Akt pathway and promotes Nrf2 phosphorylation and activation, thereby raising the level of antioxidant factors (HO-1, NQO1) and reducing the generation of ROS, which inhibit oxidative damage. CONCLUSION: Our findings suggested that the effect of TP on SI-exposed RPE cells principally relies on the regulation of oxidative stress through the PI3K/Akt/Nrf2 signaling pathway.

Protective effect of dexmedetomidine against delayed bone healing caused by morphine via PI3K/Akt mediated Nrf2 antioxidant defense system.

Background: As a class of analgesics, opioids are frequently used to treat both acute and chronic moderate to severe pain. Patients frequently receive opioid painkillers after orthopedic accidents or surgeries. Evidence suggests that opioid drug users have a 55.1% higher risk of fracture and poor bone repair than non-users of opioid drugs. The key pathogenic alterations in the incidence and progression of poor bone repair are over apoptosis and aging of osteoblasts due to the stress caused by oxidation. Dexmedetomidine (Dex) has been proven to protect against a variety of degenerative illnesses by reducing oxidative stress. However, nothing is known about how it affects bone repair. Methods: PI3K/Akt/Nrf2 pathway was detected by immunofluorescence and Western blot. SOD, CAT, JC-1, dihydroethidium and mitosox were used in the Oxidative Stress. Micro-CT, H&E and Masson's staining, immunohistochemically were performed to evaluate the therapeutic effects of DEX on calvarial defects in the morphine-induced rat model. Results: We found that morphine-induced an imbalance in the metabolism and catabolism of primary rat Osteoblasts. However, these conditions could be inhibited by DEX treatment. In the meantime, DEX induced the expression of Nrf2-regulated antioxidant enzymes such as NQO1, HO-1, GCLm, GCLc, and TrxR1. DEX-mediated Nrf2 activation is linked to the PI3K/Akt signaling system. Furthermore, it has been established that intravenous DEX enhanced the growth of bone healing in a model of a surgically produced rat cranial lesion. Conclusion: This is the first description of the unique DEX mechanism acting as a Nrf2 activator against morphine-mediated oxidative harm, raising the possibility that the substance may be used to prevent bone defects.

Protective effects of Huang-Qi-Ge-Gen decoction against diabetic liver injury through regulating PI3K/AKT/Nrf2 pathway and metabolic profiling.

ETHNOPHARMACOLOGICAL RELEVANCE: Huang-Qi-Ge-Gen decoction (HGD) is a traditional Chinese medicine prescription that has been used for centuries to treat "Xiaoke" (the name of diabetes mellitus in ancient China). However, the ameliorating effects of HGD on diabetic liver injury (DLI) and its mechanisms are not yet fully understood. AIM OF THE STUDY: To elucidate the ameliorative effect of HGD on DLI and explore its material basis and potential hepatoprotective mechanism. MATERIALS AND METHODS: A diabetic mice model was induced by feeding a high-fat diet and injecting intraperitoneally with streptozotocin (40 mg kg-1) for five days. After the animals were in confirmed diabetic condition, they were given HGD (3 or 12 g kg-1, i. g.) for 14 weeks. The effectiveness of HGD in treating DLI mice was evaluated by monitoring blood glucose and blood lipid levels, liver function, and pathological conditions. Furthermore, UPLC-MS/MS was used to identify the chemical component profile in HGD and absorption components in HGD-treated plasma. Network pharmacology and molecular docking were performed to predict the potential pathway of HGD intervention in DLI. Then, the results of network pharmacology were validated by examining biochemical parameters and using western blotting. Lastly, urine metabolites were analyzed by metabolomics strategy to explore the effect of HGD on the metabolic profile of DLI mice. RESULTS: HGD exerted therapeutic potential against the disorders of glucose metabolism and lipid metabolism, liver dysfunction, liver steatosis, and fibrosis in a DLI model mice induced by HFD/STZ. A total of 108 chemical components in HGD and 18 absorption components in HGD-treated plasma were preliminarily identified. Network pharmacology and molecular docking results of the absorbed components in plasma indicated PI3K/AKT as a potential pathway for HGD to intervene in DLI mice. Further experiments verified that HGD markedly reduced liver oxidative stress in DLI mice by modulating the PI3K/AKT/Nrf2 signaling pathway. Moreover, 19 differential metabolites between normal and DLI mice were detected in urine, and seven metabolites could be significantly modulated back by HGD. CONCLUSIONS: HGD could ameliorate diabetic liver injury by modulating the PI3K/AKT/Nrf2 signaling pathway and urinary metabolic profile.

Echinocystic acid alleviated hypoxic-ischemic brain damage in neonatal mice by activating the PI3K/Akt/Nrf2 signaling pathway.

Neonatal hypoxic-ischemic encephalopathy (HIE) is considered a major cause of death and long-term neurological injury in newborns. Studies have demonstrated that oxidative stress and apoptosis play a major role in the progression of neonatal HIE. Echinocystic acid (EA), a natural plant extract, shows great antioxidant and antiapoptotic activities in various diseases. However, it has not yet been reported whether EA exerts a neuroprotective effect against neonatal HIE. Therefore, this study was undertaken to explore the neuroprotective effects and potential mechanisms of EA in neonatal HIE using in vivo and in vitro experiments. In the in vivo study, a hypoxic-ischemic brain damage (HIBD) model was established in neonatal mice, and EA was administered immediately after HIBD. Cerebral infarction, brain atrophy and long-term neurobehavioral deficits were measured. Hematoxylin and eosin (H&E), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and dihydroethidium (DHE) staining were performed, and the contents of malondialdehyde (MDA) and glutathione (GSH) were detected. In the in vitro study, an oxygen-glucose deprivation/reperfusion (OGD/R) model was employed in primary cortical neurons, and EA was introduced during OGD/R. Cell death and cellular ROS levels were determined. To illustrate the mechanism, the PI3K inhibitor LY294002 and Nrf2 inhibitor ML385 were used. The protein expression levels of p-PI3K, PI3K, p-Akt, Akt, Nrf2, NQO1, and HO-1 were measured by western blotting. The results showed that EA treatment significantly reduced cerebral infarction, attenuated neuronal injury, and improved brain atrophy and long-term neurobehavioral deficits in neonatal mice subjected to HIBD. Meanwhile, EA effectively increased the survival rate in neurons exposed to OGD/R and inhibited oxidative stress and apoptosis in both in vivo and in vitro studies. Moreover, EA activated the PI3K/Akt/Nrf2 pathway in neonatal mice following HIBD and in neurons after OGD/R. In conclusion, these results suggested that EA alleviated HIBD by ameliorating oxidative stress and apoptosis via activation of the PI3K/Akt/Nrf2 signaling pathway.

Saikosaponin A and D attenuate skeletal muscle atrophy in chronic kidney disease by reducing oxidative stress through activation of PI3K/AKT/Nrf2 pathway.

BACKGROUND: Skeletal muscle atrophy in chronic kidney disease (CKD) leads to a decline in quality of life and increased risk of morbidity and mortality. We have obtained evidence that oxidative stress is essential in the progression of CKD-related muscle atrophy. Whether Saikosaponin A and D, two emerging antioxidants extracted from Bupleurum chinense DC, alleviate muscle atrophy remains to be further studied. The purpose of this study was to investigate the effects and mechanisms of these two components on CKD complicated with muscle atrophy. METHODS: In this research, muscle dystrophy model was established using 5/6 nephrectomized mice in vivo and in vitro with Dexamethasone (Dex)-managed C2C12 myotubes. RESULTS: The results of RNA-sequencing showed that exposure to Dex affected the antioxidant activity, catalytic activity and enzyme regulator activity of C2C12 cells. According to KEGG analysis, the largest numbers of differentially expressed genes detected were enriched in the PI3K/AKT pathway. In vivo, Saikosaponin A and D remain renal function, cross-section size, fiber-type composition and anti-inflammatory ability. These two components suppressed the expression of MuRF-1 and enhanced the expression of MyoD and Dystrophin. In addition, Saikosaponin A and D maintained redox balance by increasing the activities of antioxidant enzymes while inhibiting the excessive accumulation of reactive oxygen species. Furthermore, Saikosaponin A and D stimulated PI3K/AKT and its downstream Nrf2 pathway in CKD mice. The effects of Saikosaponin A and D on increasing the inner diameter of C2C12 myotube, reducing oxidative stress and enhancing expression of p-AKT, p-mTOR, p70S6K, Nrf2 and HO-1 proteins were observed in vitro. Importantly, we verified that these protective effects could be significantly reversed by inhibiting PI3K and knocking out Nrf2. CONCLUSIONS: In summary, Saikosaponin A and D improve CKD-induced muscle atrophy by reducing oxidative stress through the PI3K/AKT/Nrf2 pathway.

Puerarin inhibited oxidative stress and alleviated cerebral ischemia-reperfusion injury through PI3K/Akt/Nrf2 signaling pathway.

Introduction: Puerarin (PUE) is a natural compound isolated from Puerariae Lobatae Radix, which has a neuroprotective effect on IS. We explored the therapeutic effect and underlying mechanism of PUE on cerebral I/R injury by inhibiting oxidative stress related to the PI3K/Akt/Nrf2 pathway in vitro and in vivo. Methods: The middle cerebral artery occlusion and reperfusion (MCAO/R) rats and oxygen-glucose deprivation and reperfusion (OGD/R) were selected as the models, respectively. The therapeutic effect of PUE was observed using triphenyl tetrazolium and hematoxylin-eosin staining. Tunel-NeuN staining and Nissl staining to quantify hippocampal apoptosis. The reactive oxygen species (ROS) level was detected by flow cytometry and immunofluorescence. Biochemical method to detect oxidative stress levels. The protein expression related to PI3K/Akt/Nrf2 pathway was detected by using Western blotting. Finally, co-immunoprecipitation was used to study the molecular interaction between Keap1 and Nrf2. Results: In vivo and vitro studies showed that PUE improved neurological deficits in rats, as well as decreased oxidative stress. Immunofluorescence and flow cytometry indicated that the release of ROS can be inhibited by PUE. In addition, the Western blotting results showed that PUE promoted the phosphorylation of PI3K and Akt, and enabled Nrf2 to enter the nucleus, which further activated the expression of downstream antioxidant enzymes such as HO-1. The combination of PUE with PI3K inhibitor LY294002 reversed these results. Finally, co-immunoprecipitation results showed that PUE promoted Nrf2-Keap1 complex dissociation. Discussion: Taken together, PUE can activate Nrf2 via PI3K/Akt and promote downstream antioxidant enzyme expression, which could further ameliorate oxidative stress, against I/R-induced Neuron injury.

Pectolinarigenin attenuates hepatic ischemia/reperfusion injury via activation of the PI3K/AKT/Nrf2 signaling pathway.

Hepatic ischemia/reperfusion (I/R) injury is an unavoidable complication of liver hepatectomy, transplantation, and systemic shock. Pectolinarigenin (Pec) is a flavonoid with many biological activities, which include anti-inflammatory, anti-apoptotic, and antioxidant stress. This study explored whether Pec pretreatment could reduce hepatic I/R injury and the potential mechanisms at play. After pretreatment of mice and AML12 cells with Pec, I/R and hypoxia/reoxygenation (H/R) models were established. By examining markers related to liver injury, cell viability, oxidative stress, inflammatory response, and apoptosis, the effect of Pec on important processes involved in hepatic I/R injury was assessed. Protein levels associated with the PI3K/AKT/Nrf2 pathway were analyzed by relative quantification to investigate possible pathways through which Pec plays a role in the I/R process. Pec treatment corrected abnormal transaminase levels resulting from I/R injury, improved liver injury, and increased AML12 cell viability. Moreover, Pec treatment inhibited oxidative stress, inflammation and apoptosis and could activate the PI3K/AKT/Nrf2 pathway during I/R and H/R. Further studies found that LY294002 (PI3K inhibitor) suppressed the protective effect of Pec on hepatic I/R injury. In summary, our results show that Pec inhibits oxidative stress, inflammatory responses, and apoptosis, thereby attenuating I/R-induced liver injury and H/R-induced cell damage via activation of the PI3K/AKT/Nrf2 pathway.

Gastrodin protects retinal ganglion cells from ischemic injury by activating phosphatidylinositol 3-kinase/protein kinase B/nuclear factor erythroid 2-related factor 2 (PI3K/AKT/Nrf2) signaling pathway.

Glaucoma is a progressive optic neuropathy and improper treatment may cause irreversible damage to visual function. Gastrodin is an effective active substance extracted from Gastrodia elata and possesses antioxidant as well as anti-inflammatory properties. However, the therapeutic potential of gastrodin for retinal ischemia/reperfusion (I/R) injury remains unclear. We adopted oxygen and glucose deprivation/reoxygenation (OGD/R) to induce R28 cells with the aim of simulating glaucomatous neurodegeneration. CCK-8 analysis and TUNEL were applied for examining cell proliferation and apoptosis . In addition, RT-qPCR and ELISA were performed to test the releases of inflammatory factors in cells . Related indicators of intracellular oxidative stress and ROS production were detected by corresponding kits. Moreover, western blot was applied to assay the expressions of PI3K/AKT/Nrf2 pathway-related proteins. OGD/R induction contributed to the decreased cell viability and reduced Bcl-2 protein expression, while the protein contents of Bax, Cyto-C, c-caspase 9 and c-PARP as well as ROS production were ascended. The co-treatment of hypoxia and gastrodin greatly improved R28 cell viability but effectively suppressed cell apoptosis, ROS level and the releases of OGD/R-induced inflammatory factors as well as oxidative stress. In addition, OGD/R stimulation reduced Nrf2, accompanied by a decrease in the phosphorylation levels of PI3K and AKT. Gastrodin significantly promoted the activation of PI3K/AKT/Nrf2 signaling pathway in R28 cells, which was then counteracted by PI3K/AKT inhibitors. In conclusion, the present study suggested that gastrodin has a protective effect on OGD/R-induced R28 cell injury, which is achieved through the activation of the PI3K/AKT/Nrf2 signaling pathway.

FNDC5 Causes Resistance to Sorafenib by Activating the PI3K/Akt/Nrf2 Pathway in Hepatocellular Carcinoma Cells.

In this study, we aimed to reveal the resistance mechanism of hepatocellular carcinoma (HCC) cells to sorafenib by exploring the effect of FNDC5 on sorafenib-induced ferroptosis in HCC cells. We compared the expression level of FNDC5 between sorafenib-resistant and sorafenib-sensitive HCC cell lines and the level of ferroptosis between the groups after treatment with sorafenib. We knocked down FNDC5 in drug-resistant cell lines and overexpressed it in sorafenib-sensitive HCC cell lines to further demonstrate the role of FNDC5 in sorafenib-induced ferroptosis. Using PI3K inhibitors, we revealed the specific mechanism by which FNDC5 functions. In addition, we verified our findings obtained in in vitro experiments using a subcutaneous tumorigenic nude mouse model. The findings revealed that FNDC5 inhibits sorafenib-induced ferroptosis in HCC cells. In addition, FNDC5 activated the PI3K/Akt pathway, which in turn promoted the nuclear translocation of Nrf2 and increased the intracellular antioxidant response, thereby conferring resistance to ferroptosis. Our study provides novel insights for improving the efficacy of sorafenib.

The inhibitory effect and mechanism of Yi-qi-hua-yu-jie-du decoction on the drug resistance of gastric cancer stem cells based on ABC transporters.

BACKGROUND: The drug resistance of tumor stem cells is an obstacle in gastric cancer (GC) treatment and the high expression of ABC transporters is a classic reason for drug resistance. This study aimed to construct a reliable GC drug-resistant stem cell model and explore the inhibitory effect and mechanism of Yi-qi-hua-yu-jie-du medicated serum (YQHY) on the drug resistance of GC stem cells based on ABC transporters. METHODS: The tumor stemness biomarker CD44 was primary identification from WGCNA. The magnetic-activated cell sorting (MACS) method was used to separate CD44( +)BGC823/5-Fu (BGC823/5-Fu-CSCs) cells and the stemness characteristics were verified from multiple dimensions. Then, the drug resistance index and expression of ABC transporter genes MDR1 and MRP1 were detected in CD44(-)/CD44(+) cells. The inhibition and apoptosis rates of the cells administrated with YQHY or/and 5-Fu were calculated to confirm that YQHY can suppress the drug resistance of BGC823/5-Fu-CSCs. Afterwards, the effects of YQHY on the expression of MDR1 and MRP1 and the activation of the PI3K/Akt/Nrf2 pathway were observed. Finally, under the administration of IGF-1 (the activator of PI3K/Akt pathway) and Nrf2 siRNA, the mechanism of YQHY on reversing the drug resistance of BGC823/5-Fu-CSCs through inhibiting the expression of MDR1 and MRP1 via PI3K/Akt/Nrf2 was verified. RESULTS: CD44 was a reliable GC stemness biomarker and can be applied to construct the drug-resistant GC stem cell model CD44(+)BGC823/5-Fu. The growth rate, cell proliferation index, soft agar colony formation, expression of stemness specific genes and tumorigenesis ability of CD44(+)BGC823/5-Fu cells were significantly higher than those of CD44(-)BGC823/5-Fu cells. BGC823/5-Fu-CSCs exhibited strong drug resistance to 5-Fu and high expression of ABC transporter genes MDR1 and MRP1 compared to CD44(-) cells. YQHY increased the inhibition and apoptosis rates to efficiently inhibit the drug resistance of BGC823/5-Fu-CSCs. Meanwhile, it suppressed the expression of MDR1 and MRP1 and restrained the activation of PI3K/Akt/Nrf2 signaling pathway. Finally, it was found that IGF-1 partially restored the activation of PI3K/Akt/Nrf2 pathway, alleviated the inhibition of MDR1 and MRP1, blocked the proliferation-inhibitory and apoptosis-promotion effects. YQHY and si-Nrf2 synergistically suppressed the MDR1/MRP1 expression and the drug resistance of BGC823/5-Fu-CSCs. CONCLUSIONS: CD44 was a reliable GC stemness biomarker, and the high expression of ABC transporter genes MDR1 and MRP1 was an important feature of drug-resistant stem cells. YQHY inhibited the MDR1 and MRP1 expression via PI3K/Akt/Nrf2 pathway, thus reversing the drug resistance of BGC823/5-Fu-CSCs.

Arbutin attenuates LPS-induced acute kidney injury by inhibiting inflammation and apoptosis via the PI3K/Akt/Nrf2 pathway.

BACKGROUND: Arbutin (Ar) has anti-oxidative and anti-inflammatory activities. However, the effects of Ar on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) are not clear. PURPOSE: This study aimed to investigate the effects of Ar on LPS-induced AKI in rats. METHODS: The possible data regarding the effects of Ar on AKI were collected by network pharmacology research. Histological changes in the kidney and the levels of blood urea nitrogen, serum creatinine, and kidney injury molecule 1 were measured to assess the effects of Ar on renal function in LPS-induced AKI. The levels of inflammatory were detected by live small-animal imaging, cytometric bead array and enzyme linked immunosorbent assay. The levels of reactive oxygen species and apoptosis of primary kidney cells were detected by flow cytometry. The oxidative stress-related markers were detected by the cuvette assay. The TLR4/NF-κB and PI3K/Akt/Nrf2 levels and apoptosis were detected by Western blot analysis. The effects of GDC-0068 (GDC, Akt inhibitor) on Ar interposed on LPS-induced NRK-52e cell apoptosis were investigated by flow cytometry. RESULTS: The data collected by network pharmacology suggested that Ar might inhibit AKI by exerting an anti-inflammatory effect and regulating the Akt signaling pathway. The experimental results showed that Ar markedly improved renal function, and attenuated inflammation and cell apoptosis via regulating PI3K/Akt/Nrf2 pathway following LPS challenge in vivo, which blocked by GDC effectively in vitro. CONCLUSION: In a word, this study demonstrated that Ar attenuated LPS-induced AKI by inhibiting inflammation and apoptosis via the PI3K/Akt/Nrf2 pathway.