Proximal tubular MBD2 promotes autophagy to drive the progression of AKI caused by vancomycin via regulation of miR-597-5p/S1PR1 axis.

Our recent investigation has indicated that the global deletion of MBD2 can mitigate the progression of AKI induced by VAN. Nevertheless, the role and regulatory mechanisms of proximal tubular MBD2 in this pathophysiological process have yet to be elucidated. Our preceding investigation revealed that autophagy played a crucial role in advancing AKI induced by VAN. Consequently, we postulated that MBD2 present in the proximal tubule could upregulate the autophagic process to expedite the onset of AKI. In the present study, we found for the first time that MBD2 mediated the autophagy production induced by VAN. Through the utilization of miRNA chip analysis, we have mechanistically demonstrated that MBD2 initiates the activation of miR-597-5p through promoter demethylation. This process leads to the suppression of S1PR1, which results in the induction of autophagy and apoptosis in renal tubular cells. Besides, PT-MBD2-KO reduced autophagy to attenuate VAN-induced AKI via regulation of the miR-597-5p/S1PR1 axis, which was reversed by rapamycin. Finally, the overexpression of MBD2 aggravated the diminished VAN-induced AKI in autophagy-deficient mice (PT-Atg7-KO). These data demonstrate that proximal tubular MBD2 facilitated the process of autophagy via the miR-597-5p/S1PR1 axis and subsequently instigated VAN-induced AKI through the induction of apoptosis. The potentiality of MBD2 being a target for AKI was established.

EGFR mediated the renal cell apoptosis in rhabdomyolysis-induced model via upregulation of autophagy.

AIMS: Rhabdomyolysis is a life-threatening condition. One of the most common complications of rhabdomyolysis is acute kidney injury (AKI), and 10 % of all AKI patients present with rhabdomyolysis. EGFR is associated with different types of AKI. However, the function and regulatory mechanism of EGFR in rhabdomyolysis-induced AKI model remain unknown. Here, we performed the experiments to explore the role of EGFR in this model. MAIN METHODS: We used proximal tubule-specific Atg7 knockout mice and Wa-2 mice to establish animal models. Then, the samples were collected for pathology assay and IB detection. In vitro, the BUMPT cells treated with myoglobin were collected for the detection of apoptosis and autophagy. IB detection were processed for the analysis of protein expressions, FCM analysis for the cell apoptosis, GFP-LC3 transfection and immunofluorescent for autophagy. KEY FINDINGS: EGFR promotes autophagy to mediate rhabdomyolysis-induced AKI via STAT3/Atg7 axis, and gefitinib is a potential therapeutic option for AKI. Here, we demonstrated that EGFR was activated by myoglobin and glycerol both in vitro and in vivo, respectively. Genetic or pharmacological inhibition of EGFR ameliorated myoglobin and glycerol-induced renal cell apoptosis. Mechanistically, EGFR mediated autophagy induction via STAT3/Atg7 axis, thereby resulting in kidney cell apoptosis. Furthermore, Wa-2 mice or gefitinib treatment prevented the progression of rhabdomyolysis-induced AKI as well as renal cell apoptosis and autophagy via inhibiting STAT3/Atg7 axis. SIGNIFICANCE: Researchers can use this finding to better study the function and regulatory mechanism of EGFR in RM-induced AKI model. And gefitinib represents a potential target for treatment of AKI.

CircRNA_45478 promotes ischemic AKI by targeting the miR-190a-5p/PHLPP1 axis.

A few studies suggested that circular RNAs were involved in the development of ischemic acute kidney injury (AKI). However, the function and regulation mechanism of circRNA_45478 in ischemic AKI remains unknown. In the present study, ischemic injury induced the expressions of circRNA_45478 in mouse proximal tubule-derived cell lines (BUMPT cells) and kidneys of C57BL/6 mice. Functionally, circRNA_45478 mediated I/R-induced apoptosis in BUMPT cells. Mechanistically, circRNA_45478 upregulated the expression of Pleckstrin homology (PH) domain leucine-rich repeat protein phosphatase 1 (PHLPP1) via sponging of microRNA (miR)-190a-5p. Finally, inhibition of circRNA_45478 significantly alleviated the progression of ischemic AKI through regulation of the miR-190a-5p/PHLPP1 pathway. Taken together, our data showed that circRNA_45478/miR-190a-5p/PHLPP1 axis mediated the progression of ischemic AKI.

Inhibition of PKC-δ reduce rhabdomyolysis-induced acute kidney injury.

Despite extensive research, the mechanisms underlying rhabdomyolysis-induced acute kidney injury (AKI) remain largely elusive. In this study, we established both cell and murine models of rhabdomyolysis-induced AKI by using myoglobin and glycerin, respectively, and provided evidence that protein kinase Cδ (PKC-δ) was activated in both models and subsequently promoted cell apoptosis. Moreover, we found that this detrimental effect of PKC-δ activation can be reversed by its pharmaceutical inhibitor rottlerin. Furthermore, we detected and confirmed the existence of PKC-δ-mediated myoglobin-induced cell apoptosis and the expression of TNF-α and IL1-ß via regulation of the p38MAPK and ERK1/2 signalling pathways. In summary, our research revealed the role of PKC-δ in renal cell apoptosis and suggests that PKC-δ is a viable therapeutic target for rhabdomyolysis-induced AKI.

CircRNA_30032 promotes renal fibrosis in UUO model mice via miRNA-96-5p/HBEGF/KRAS axis.

In this study, we investigated the role of circular RNA_30032 (circRNA_30032) in renal fibrosis and the underlying mechanisms. The study was carried out using TGF-ß1-induced BUMPT cells and unilateral ureteral obstruction (UUO)-induced mice, respectively, as in vitro and in vivo models. CircRNA_30032 expression was significantly increased by 9.15- and 16.6-fold on days 3 and 7, respectively, in the renal tissues of UUO model mice. In TGF-ß1-treated BUMPT cells, circRNA_30032 expression was induced by activation of the p38 mitogen-activated protein kinase signaling pathway. Quantitative real-time PCR, western blotting and dual luciferase reporter assays showed that circRNA_30032 mediated TGF-ß1-induced and UUO-induced renal fibrosis by sponging miR-96-5p and increasing the expression of profibrotic proteins, including HBEGF, KRAS, collagen I, collagen III and fibronectin. CircRNA_30032 silencing significantly reduced renal fibrosis in UUO model mice by increasing miR-96-5p levels and decreasing levels of HBEGF and KRAS. These results demonstrate that circRNA_30032 promotes renal fibrosis via the miR-96-5p/HBEGF/KRAS axis and suggest that circRNA_30032 is a potential therapeutic target for treatment of renal fibrosis.

Circ_0134111 knockdown relieves IL-1ß-induced apoptosis, inflammation and extracellular matrix degradation in human chondrocytes through the circ_0134111-miR-515-5p-SOCS1 network.

BACKGROUND: Osteoarthritis (OA) is characterized by chondrocyte injury and dysfunction, such as excessive apoptosis, inflammatory response and extracellular matrix (ECM) degradation. Circular RNA (circRNA) deregulation is reported to be involved in OA. Our study aimed to explore the role of circ_0134111 in OA. METHODS: Human chondrocytes were treated with interleukin-1ß (IL-1ß) to mimic OA cell model. The expression of circ_0134111, miR-515-5p and suppressor of cytokine signaling 1 (SOCS1) mRNA was measured by real-time quantitative polymerase chain reaction (RT-qPCR), and the protein levels of SOCS1 and apoptosis-/inflammation-/ECM-related markers were determined by western blot. Cell proliferation and cell apoptosis were assessed using cell counting kit-8 (CCK-8) and flow cytometry assay, respectively. For mechanism analysis, the predicted interaction between miR-515-5p and circ_0134111 or SOCS1 was verified by dual-luciferase reporter assay, pull-down assay and RNA immunoprecipitation (RIP) assay. Rescue experiments were performed to explore the interplay between miR-515-5p and circ_0134111 or SOCS1. RESULTS: Circ_0134111 was overexpressed in OA cartilage tissues and IL-1ß-induced chondrocytes. IL-1ß-induced chondrocyte apoptosis, inflammatory responses and ECM degradation were alleviated by circ_0134111 knockdown or miR-515-5p restoration. Circ_0134111 acted as miR-515-5p sponge to regulate miR-515-5p expression, and miR-515-5p deficiency reversed the effects of circ_0134111 knockdown in IL-1ß-induced chondrocytes. MiR-515-5p directly bound to SOCS1, and circ_0134111 decoyed miR-515-5p to increase SOCS1 level. MiR-515-5p restoration alleviated IL-1ß-induced chondrocyte apoptosis, inflammatory responses and ECM degradation, While SOCS1 overexpression partly abolished these effects. CONCLUSION: Circ_0134111 knockdown alleviated apoptosis, inflammatory responses and ECM degradation in OA cell model by mediating the miR-515-5p-SOCS1 network, hinting that circ_0134111 was involved in OA progression.

[Association between maternal alcohol consumption and risk of congenital heart disease in offspring: a Meta analysis].

OBJECTIVE: To study the association between maternal alcohol consumption and the risk of congenital heart disease (CHD) in offspring. METHODS: PubMed, Cochrane Library, Web of Science, Google Scholar, China Biology Medicine disc, Wanfang Database, CNKI Database, and Weipu Database were searched for the articles on the association between maternal alcohol consumption and congenital heart disease in offspring. These articles were published up to November 30, 2019. A random effects model or a fixed effects model was used for the pooled analysis of the results of each study, and then the pooled effective value and its 95%CI were calculated. A subgroup analysis was performed to explore heterogeneous regulators. Funnel plots and an Egger's test were used to assess publication bias. RESULTS: A total of 4 409 articles were searched, and 55 articles were finally included in this analysis, among which there were 6 cohort studies and 49 case-control studies. The Meta analysis showed heterogeneity across all studies (I2=74%, P<0.01). The random effects model showed that maternal alcohol consumption was associated with CHD in offspring, with an OR of 1.18 (95%CI: 1.09-1.28). The Egger's test showed a certain degree of publication bias (P<0.05), and after adjustment, the pooled OR of CHD in offspring was 1.10 (95%CI: 1.01-1.21). CONCLUSIONS: Maternal alcohol consumption may increase the risk of CHD in offspring.

Evaluating the osteoimmunomodulatory properties of micro-arc oxidized titanium surface at two different biological stages using an optimized in vitro cell culture strategy.

It is known that introducing a porous ceramic coating on titanium (Ti) implant surface fabricated by micro-arc oxidation (MAO) could enhance the differentiation of osteoblasts. However, the osteogenic capacity of MAO-fabricated coating still remains unknown when immune cells especially macrophages are involved. The influence of the inflammatory microenvironment and the co-influence of the inflammatory microenvironment and surface characteristics of MAO-fabricated coating on osteoblast response need to be explored. In this study, a new in vitro cell culture strategy is proposed by mimicking the biological events happened after implantation based on the recruitment of osteoblasts to biomaterial surfaces to investigate biological performances of MAO-modified Ti surface. It is found that macrophages grown on MAO-modified Ti surface were switched to M1-like phenotype, evidenced by the promoted expressions of inflammatory genes (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß) and production of pro-inflammatory cytokine TNF-α. Moreover, the inflammatory microenvironment created by macrophage/MAO-modified Ti surface interactions could promote the collagen syntheses and matrix mineralization of osteoblast-like cells grown tissue culture plate. When osteoblasts were cultured on MAO-modified Ti surface and cultured by macrophage/MAO-modified Ti surface conditioned medium (CM), the alkaline phosphatase (ALP) activity and collagen synthesis of osteoblast-like cells were promoted. This study suggests that MAO-modified Ti surface is beneficial for osteogenesis at both stages after implantation (before and after osteoblast recruitment to biomaterial surfaces).

lncRNA NR_038323 Suppresses Renal Fibrosis in Diabetic Nephropathy by Targeting the miR-324-3p/DUSP1 Axis.

Several studies have suggested that long intergenic noncoding RNAs are involved in the progression of diabetic nephropathy (DN). However, the exact role and regulatory mechanism of long noncoding RNA (lncRNA) NR_038323 in diabetic nephropathy (DN) remain largely unclear. In the present study, we found that lncRNA NR_038323 overexpression ameliorated the high glucose (HG)-induced expression levels of collagen I, collagen IV, and fibronectin, whereas lncRNA NR_038323 knockdown exerted the opposite effects. Moreover, the results of bioinformatic prediction, luciferase assay, and fluorescence in situ hybridization (FISH) demonstrated that lncRNA NR_038323 directly interacted with miR-324-3p. Additionally, miR-324-3p mimic aggravated the HG-induced expression levels of collagen I, collagen IV, and fibronectin by dual-specificity protein phosphatase-1 (DUSP1) expression to activate p38 mitogen-activated protein kinase (MAPK) and ERK1/2 pathways. In contrast, overexpression of DUSP1 attenuated the HG-induced expression levels of collagen I, collagen IV, and fibronectin via inactivation of p38 MAPK and ERK1/2 pathways. In addition, lncRNA NR_038323 knockdown increased the expression levels of collagen I, collagen IV, and fibronectin by upregulating DUSP1 expression during HG treatment, which were markedly reversed by miR-324-3p inhibitor. Furthermore, these molecular changes were verified in the human kidney samples of DN patients. Finally, overexpression of lncRNA NR_038323 ameliorated the interstitial fibrosis in STZ-induced diabetic nephrology (DN) rat via miR-324-3p/DUSP1/p38MAPK and ERK1/2 axis. In conclusion, our data indicate that overexpression of lncRNA NR_038323 may suppress HG-induced renal fibrosis via the miR-324-3p/DUSP1/p38MAPK and ERK1/2 axis, which provides new insights into the pathogenesis of DN.

Atg7 mediates renal tubular cell apoptosis in vancomycin nephrotoxicity through activation of PKC-δ.

Recent studies have shown that autophagy exhibits a renoprotective role in various models of acute kidney injury (AKI). However, its role in vancomycin (Van)-induced AKI remains largely unclarified. This study was the first to indicate that autophagy was rapidly activated in both human kidney-2 cells and renal tissues, and mammalian target of rapamycin (mTOR) was inactivated via the suppression of ERK1/2 and mTOR during Van treatment. Interestingly, for both in vitro and in vivo experiments, the suppression of autophagy via chloroquine and PT-Atg7-KO significantly ameliorated Van-induced kidney injury and renal tubular cell apoptosis. Global gene expression analysis indicated that the expression levels of 6159 genes were induced by Van treatment in the kidney cortical tissues of PT-Atg7 wild-type mice, and 18 of them were notably suppressed in PT-Atg7-KO mice. These 18 genes were further classified as programmed cell death, protein binding, signal transduction, E3 ubiquitin ligase, nucleoside diphosphate kinase activity, and E1-like activating enzyme. Unexpectedly, following Van treatment, PKC-δ expression was found to be highest among the 4 genes related to cell death, which was remarkably suppressed in vitro and in PT-Atg7-KO mice. In addition, Atg7 could induce renal cell apoptosis during Van treatment via binding to PKC-δ. Likewise, the inhibition of PKCδ ameliorated Van-induced apoptosis in human kidney-2 cells and kidney tissues. Furthermore, the data showed that PT-Atg7-KO exerted a renoprotective effect against Van-induced nephrotoxicity, but this effect was lost after injection with myc-tagged PKCδ. Taken altogether, these results indicate that Van induces autophagy by suppressing the activation of the ERK1/2 and mTOR signaling pathway. In addition, Atg7 mediates Van-induced AKI through the activation of PKCδ. In sum, autophagy inhibition may serve as a novel therapeutic target for treating nephrotoxic AKI induced by Van.-Xu, X., Pan, J., Li, H., Li, X., Fang, F., Wu, D., Zhou, Y., Zheng, P., Xiong, L., Zhang, D. Atg7 mediates renal tubular cell apoptosis in vancomycin nephrotoxicity through activation of PKC-δ.

Association of microstructural and mechanical properties of cancellous bone and their fracture risk assessment tool scores.

This study is to investigate the association between fracture probabilities determined by using the fracture risk assessment tool (FRAX) and the microstructure and mechanical properties of femoral bone trabecula in osteoporosis (OP) and osteoarthritis (OA) patients with hip replacements. By using FRAX, we evaluated fracture risks of the 102 patients with bone replacements. Using micro CT scanning, we obtained the analysis parameters of microstructural properties of cancellous bone. Through morphometric observations, fatigue tests and compression tests, we obtained parameters of mechanical properties of cancellous bones. Relevant Pearson analysis was performed to investigate the association between the fracture probability and the microstructure and mechanical properties of femoral bone trabecula in patients. Fifteen risk factors in FRAX were compared between OP and OA patients. FRAX hip fracture risk score and major osteoporotic in OP and OA patients were significantly different. FRAX was associated with tissue bone mineral density and volumetric bone mineral density. Our study suggests that the probabilities of major osteoporotic and hip fracture using FRAX is associated with bone mass but not with micro bone quality.

Avascular necrosis of the femoral head due to the bilateral injection of heroin into the femoral vein: A case report.

In this study, we report a case of avascular necrosis of the femoral head (ANFH) caused by the bilateral intravenous injection of heroin into the femoral vein. The patient had not used steroids, did not smoke and did not drink excessively. The patient did not present with any systemic diseases that may cause ANFH. ANFH often causes changes to the bone mass of the femoral head, particularly, the weight-bearing bone region. Imaging examination revealed that in addition to the bilateral hip joints, widespread changes to the bone mass existed in the peripheral area, where phlebitis and disseminated thrombosis had been caused by the injection of heroin. These results suggest that this ANFH case was related to the injection of heroin. This case is different from other cases of ANFH which have been caused by steroids and other factors, including smoking, alcohol intake and cytotoxic agents.

A signal to noise ratio measurement for single shot laser pulses by use of an optical Kerr gate.

A new design of signal to noise ratio (SNR) measurement for single shot laser pulses, based on a stepped grating and an optical Kerr gate (OKG), is presented. A single shot laser pulse was simultaneously divided into multi-pulses in both time and space. Intensity-space distribution of laser multi-pulses, which was recorded with a CCD detector, was transformed into intensity-time distribution. Time resolution of 1.95 ps and detection time range of 42.9 ps were obtained, respectively. Moreover, optical spatial localization attenuators were introduced into optical path to acquire wide dynamic range in the SNR measurement and, as a result, the dynamic range has been extended remarkably.