Loureirin C improves mitochondrial function by promoting NRF2 nuclear translocation to attenuate oxidative damage caused by renal ischemia-reperfusion injury.

Acute kidney injury (AKI) is a common clinical syndrome worldwide, with no effective treatment strategy. Renal ischemia-reperfusion (IR) injury is one of the main AKI features, and the excessive reactive oxygen species (ROS) production during reperfusion causes severe oxidative damage to the kidney. Loureirin C (LC), an active ingredient in the traditional Chinese medicine Chinese dragon's blood, possesses excellent antioxidative properties, but its role in renal IR injury is not clear. In this study, we evaluated the protective effects of LC against renal IR injury in vivo and in vitro by establishing a mice renal IR injury model and a human proximal renal tubular epithelial cell (HK-2) hypoxia/reoxygenation (HR) model. We found that LC ameliorated renal function and tissue structure injury and inhibited renal oxidative stress and ferroptosis in vivo. In vitro, LC scavenged ROS and attenuated mitochondrial dysfunction in HK-2 cells, thereby inhibiting oxidative cellular injury. Furthermore, we found that LC effectively promoted nuclear factor erythroid 2-related factor 2 (NRF2) nuclear translocation and activated downstream target genes heme oxygenase 1 (HO-1) and NADPH quinone oxidoreductase-1 (NQO-1) to enhance cellular antioxidant function. Moreover, NRF2 knockdown and pharmacological inhibition of NRF2 partially eliminated the protective effect of LC. These results confirm that LC can effectively inhibit renal IR injury, and the mechanism may be associated with NRF2 activation by LC.

Transcription factor EB modulates the homeostasis of reactive oxygen species in intestinal epithelial cells to alleviate inflammatory bowel disease.

Transcription factor EB (TFEB), a master lysosomal biogenesis and autophagy regulator, is crucial for cellular homeostasis, and its abnormality is related to diverse inflammatory diseases. Genetic variations in autophagic genes are associated with susceptibility to inflammatory bowel disease (IBD); however, little is known about the role and mechanism of TFEB in disease pathogenesis. In this study, we found that the genetic deletion of TFEB in mouse intestinal epithelial cells (IEC) caused intestinal barrier dysfunction, leading to increased susceptibility to experimental colitis. Mechanistically, TFEB functionally protected IEC in part through peroxisome proliferator-activated receptor gamma coactivator 1alpha (TFEB-PGC1α axis) induction, which consequently suppressed reactive oxygen species. TFEB can directly regulate PGC-1α transcription to control antioxidation level. Notably, TFEB expression is impaired and downregulated in the colon tissues of IBD patients. Collectively, our results indicate that intestinal TFEB participates in oxidative stress regulation and attenuates IBD progression.

Classification and clinical significance of the posterior group of renal calyces.

To study the anatomical orientation of the posterior group of calyces based on reconstructed images of computerized tomography urography (CTU) and provide a novel classification with its clinical significance. Clinical data of a total of 1321 patients, who underwent CTU examination in our hospital were retrospectively analyzed. Among these, a total of 2642 3-dimensional reconstructed images of CTU scans were considered in this study. Based on the morphology of the renal calyces and the influence on the establishment of surgical access, the posterior group renal calyces are classified into 3 major types including pot-belly type, classically branched and elongated branched. The classically branched type is further classified into 3 sub-types: a, b and c, based on the association of minor calyces of the posterior group to the major calyces. Type a is derived from 1 group of major calyces only, type b is derived from 2 groups of major calyces simultaneously, and type c is derived from 3 groups of major calyces simultaneously. Statistical findings revealed that all kidneys possess posterior group calyces. The percentage of occurrence of pot-belly type, classically branched and elongated branched is 8.06%, 73.13%, and 18.81%, respectively. The anatomical typing of the classical branching type occurred in 19.36%, 68.17%, and 12.47% for types a, b, and c, respectively. In this study, the posterior group calyces were found to be present across all patients. The posterior group calyces were highest in the classical branching type, of which anatomical typing was highest in type b. The typing of the posterior group of calyces could provide an anatomical basis for percutaneous nephrolithotomy (PCNL) puncture from the posterior group.

TFAP2C Knockdown Sensitizes Bladder Cancer Cells to Cisplatin Treatment via Regulation of EGFR and NF-κB.

Cisplatin is the first-line chemotherapy for advanced or metastatic bladder cancer. Nevertheless, approximately half of patients with BCa are insensitive to cisplatin therapy or develop cisplatin resistance during the treatment process. Therefore, it is especially crucial to investigate ways to enhance the sensitivity of tumor cells to cisplatin. Transcription factor AP-2 gamma (TFAP2C) is involved in cancer development and chemotherapy sensitivity. However, its relationship with chemotherapy has not been studied in BCa. In this study, we aimed to investigate the therapeutic potential of TFAP2C in human BCa. Results based on TCGA (The Cancer Genome Atlas), GTEx (The Genotype-Tissue Expression) and GEO (Gene Expression Omnibus) data showed that TFAP2C expression was upregulated in BCa tissues and that its high expression was associated with poor prognosis. Meanwhile, we demonstrated the overexpression of TFAP2C in BCa clinical specimens. Subsequently, in vitro, we knocked down TFAP2C in BCa cells and found that TFAP2C knockdown further increased cell cycle arrest and apoptosis caused by cisplatin. In addition, the inhibitory effect of cisplatin on BCa cell migration and invasion was enhanced by TFAP2C knockdown. Our data indicated that cisplatin increased epidermal growth factor receptor (EGFR) and nuclear factor-kappaB (NF-κB) activation levels, but TFAP2C knockdown suppressed this effect. Finally, in vivo data further validated these findings. Our study showed that TFAP2C knockdown affected the activation levels of EGFR and NF-κB and enhanced the anti-tumor effects of cisplatin in vivo and in vitro. This provides a new direction to improve the efficacy of traditional cisplatin chemotherapy.

CDK1 Promotes Epithelial-Mesenchymal Transition and Migration of Head and Neck Squamous Carcinoma Cells by Repressing ∆Np63α-Mediated Transcriptional Regulation.

∆Np63α is a key transcription factor overexpressed in types of squamous cell carcinomas (SCCs), which represses epithelial-mesenchymal transition (EMT) and cell migration. In this study, we found that CDK1 phosphorylates ∆Np63α at the T123 site, impairing its affinity to the target promoters of its downstream genes and its regulation of them in turn. Database analysis revealed that CDK1 is overexpressed in head and neck squamous cell carcinomas (HNSCCs), especially the metastatic HNSCCs, and is negatively correlated with overall survival. We further found that CDK1 promotes the EMT and migration of HNSCC cells by inhibiting ∆Np63α. Altogether, our study identified CDK1 as a novel regulator of ΔNp63α, which can modulate EMT and cell migration in HNSCCs. Our findings will help to elucidate the migration mechanism of HNSCC cells.

HO-1 Contributes to Luteolin-Triggered Ferroptosis in Clear Cell Renal Cell Carcinoma via Increasing the Labile Iron Pool and Promoting Lipid Peroxidation.

Ferroptosis, a novel form of regulated cell death characterized by disrupted iron metabolism and the accumulation of lipid peroxides, has exhibited enormous potential in the therapy of cancer particularly clear cell renal cell carcinoma (ccRCC). Luteolin (Lut), a natural flavonoid widely existing in various fruits and vegetables, has been proven to exert potent anticancer activity in vitro and in vivo. However, previous studies on the anticancer mechanism of Lut have been shown in apoptosis but not ferroptosis. In the present study, we identified that Lut substantially inhibited the survival of ccRCC in vitro and in vivo, and this phenomenon was accompanied by excessively increased intracellular Fe2+ and abnormal depletion of GSH. In addition, Lut induced the imbalance of mitochondrial membrane potential, classical morphological alterations of mitochondrial ferroptosis, generation of ROS, and occurrence of lipid peroxidation in an iron-dependent manner in ccRCC cells. However, these alterations induced by Lut could be reversed to some extent by the iron ion chelator deferiprone or the ferroptosis inhibitor ferrostatin-1, indicating that ccRCC cells treated with Lut underwent ferroptosis. Mechanistically, molecular docking further established that Lut probably promoted the heme degradation and accumulation of labile iron pool (LIP) by excessively upregulating the HO-1 expression, which led to the Fenton reaction, GSH depletion, and lipid peroxidation in ccRCC, whereas blocking this signaling pathway evidently rescued the Lut-induced cell death of ccRCC by inhibiting ferroptosis. Altogether, the current study shows that the natural compound monomer Lut exerted anticancer efficacy by excessively upregulating HO-1 expression and activating LIP to trigger ferroptosis in ccRCC and could be a promising and potent drug candidate for ccRCC treatment.

Naringin Alleviates H2O2-Inhibited Osteogenic Differentiation of Human Adipose-Derived Stromal Cells via Wnt/ß-Catenin Signaling.

Osteoporosis is an age-related systemic bone disease that places a heavy burden on patients and society. In this study, we aimed to investigate the effects of naringin (NAR) on the osteogenic differentiation of human adipose-derived stromal cells (ADSCs). The results demonstrated that NAR pretreatment effectively abated H2O2-induced cell death and ROS accumulation in ADSCs undergoing osteogenic differentiation (ADSCs-OD). In addition, we also observed that the impaired extracellular matrix mineralization and ALP activity in H2O2-stimulated ADSCs-OD were notably rescued by NAR pretreatment. Moreover, the effects of H2O2 exposure on Wnt/ß-catenin signaling in ADSCs-OD were largely reversed by NAR pretreatment. Collectively, our findings indicated that NAR could protect ADSCs-OD against H2O2-inhibited osteogenic differentiation.

microRNA-486-5p is implicated in the cisplatin-induced apoptosis and acute inflammation response of renal tubular epithelial cells by targeting HAT1.

The proinflammatory property of cisplatin is potentially destructive and contributes to the pathogenesis of acute kidney injury (AKI). The role and upstream regulatory mechanism of histone acetyltransferase 1 (HAT1) in acute kidney inflammation are still unknown. We performed RNA sequencing to filter differentially expressed microRNAs (miRNAs) in the kidney tissue of mice with AKI induced by cisplatin and ischemia-reperfusion. Here, we found that miR-486-5p was upregulated and that the expression of HAT1 was reduced in AKI mouse models and injured human renal proximal tubular epithelial cell (HK-2) model induced by cisplatin. miR-486-5p is implicated in cisplatin-induced kidney damage in vivo. Bioinformatics analysis predicted a potential binding site between miR-486-5p and HAT1. The Luciferase reporter assay and Western blot confirmed that miR-486-5p directly targeted the 3'-untranslated region of HAT1 mRNA and inhibited its expression in the cytoplasm of HK-2 cells. In the in vitro study, inhibiting miR-486-5p reduced apoptosis, and the expression of proinflammatory mediators was induced by cisplatin in HK-2 cells. Simultaneously, the downregulation of miR-486-5p inhibited the activation of the toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB). We further found that HAT1 could inhibit apoptosis and the activation of cisplatin on the TLR4/NF-κB pathway and that the upregulation of miR-486-5p reversed this effect. Therefore, the upregulation of miR-486-5p targeting HAT1 promoted the cisplatin-induced apoptosis and acute inflammation response of renal tubular epithelial cells by activating the TLR4/NF-κB pathway, providing a new basis to highlight the potential intervention of regulating the miR-486-5p/HAT1 axis.

LncRNA TUG1 attenuates ischaemia-reperfusion-induced apoptosis of renal tubular epithelial cells by sponging miR-144-3p via targeting Nrf2.

Renal ischaemia/reperfusion (I/R) injury may induce kidney damage and dysfunction, in which oxidative stress and apoptosis play important roles. Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are reported to be closely related to renal I/R, but the specific molecular mechanism is still unclear. The purpose of this research was to explore the regulatory effect of lncRNA TUG1 on oxidative stress and apoptosis in renal I/R injury. This research revealed that in renal I/R injury and hypoxia/reperfusion (H/R) injury in vitro, the expression level of lncRNA TUG1 was upregulated, and oxidative stress levels and apoptosis levels were negatively correlated with the expression level of lncRNA TUG1. Using bioinformatics databases such as TargetScan and microRNA.org, microRNA-144-3p (miR-144-3p) was predicted to be involved in the association between lncRNA TUG1 and Nrf2. This study confirmed that the level of miR-144-3p was significantly reduced following renal I/R injury and H/R injury in vitro, and miR-144-3p was determined to target Nrf2 and inhibit its expression. In addition, lncRNA TUG1 can reduce the inhibitory effect of miR-144-3p on Nrf2 by sponging miR-144-3p. In summary, our research shows that lncRNA TUG1 regulates oxidative stress and apoptosis during renal I/R injury through the miR-144-3p/Nrf2 axis, which may be a new treatment target for renal I/R injury.

MicroRNA-205 inhibits the apoptosis of renal tubular epithelial cells via the PTEN/Akt pathway in renal ischemia-reperfusion injury.

Renal ischemia-reperfusion injury (IRI) is the main cause of acute kidney injury (AKI). Many studies on renal IRI have been performed recently, but effective treatments are still lacking. Evidence exists that small endogenous noncoding RNAs are involved in the ischemia-reperfusion process. This article aims to investigate whether microRNA-205 (miR-205) is involved in this process and to determine its role in the hypoxia-induced injury of renal tubular epithelial cells (TECs). We found that miR-205 was significantly downregulated in rats with renal IRI and in HK-2 cells with hypoxia-reoxygenation injury (HRI) in vitro. In vitro, overexpression of intracellular miR-205 by transfection of a miR-205 mimic significantly reduced apoptosis, and this antiapoptotic effect was antagonized by a miR-205 inhibitor. Moreover, we confirmed that PTEN is a target of miR-205. miR-205 exerted its protective effect by inhibiting HK-2 cell apoptosis and promoting HK-2 cell proliferation by inhibiting the expression of PTEN during HRI, and this protective effect was blocked by silencing PTEN. Therefore, we confirmed that miR-205 may target the PTEN/Akt signaling pathway to alleviate hypoxia-induced renal cell damage. miR-205 may be a new potential target for the treatment of renal IRI.