Analysis of Differentially Expressed Long Noncoding RNA in Renal Ischemia-Reperfusion Injury.

BACKGROUND: Renal ischemia-reperfusion (IR) injury is one of the major causes of acute renal failure which seriously endangers the health and life of patients. Currently, there is still lack of comprehensive knowledge of the molecular mechanism of renal IR injury, and the regulatory role of long noncoding RNA (lncRNA) in renal IR damage remains poorly understood. AIM: The aim of this study was to analyze the expression spectrum of lncRNA in renal IR damage in mice and to explore specific lncRNA that may be involved in regulating the development of human renal IR injury. METHODS: RNA-Seq was used to investigate the lncRNA profile of renal IR injury in a mouse model, and conservation analysis was performed on mouse lncRNAs with differential expression (fragments per kilobase of transcript per million mapped reads ≥2) by BLASTN. The potential functions and associated pathways of the differentially expressed lncRNA were explored by bioinformatics analysis. The cell hypoxia model was used to detect the expression of the candidate lncRNA. RESULTS: Of the 45,923 lncRNA transcripts detected in the samples, and 5,868 lncRNAs were found to be significantly differentially expressed (p < 0.05 and fold change ≥ 2) in 24-h IR kidney tissue compared to the expression in the control group. It was found that 56 differently expressed mouse lncRNA transcripts have human homology by analyzing the conserved sequences. We also found that lncRNA-NONHSAT183385.1 expression significantly increased in HK2 cells after 24 h of hypoxia and increased further 6 h after reoxygenation, and after 24 h of reoxygenation it was dramatically downregulated, indicating that NONHSAT183385.1 may be involved in the pathophysiological process of renal tubular epithelial cells in response to ischemia in human renal IR. CONCLUSION: Our study revealed differentially expressed lncRNAs in renal IR damage in mice and identified a set of conserved lncRNAs, which would help to explore lncRNAs that may play important regulatory roles in human renal IR injury.

Inhibition of Notch signaling facilitates the differentiation of human-induced pluripotent stem cells into neural stem cells.

Neural stem cells (NSCs) derived from induced pluripotent stem cells (iPSCs) are becoming an appealing source of cell-based therapies of brain diseases. As such, it is important to understand the molecular mechanisms that regulate the differentiation of iPSCs toward NSCs. It is well known that Notch signaling governs the retention of stem cell features and drives stem cells fate. However, further studies are required to investigate the role of Notch signaling in the NSCs differentiation of iPSCs. In this study, we successfully generated NSCs from human iPSCs using serum-free medium supplemented with retinoic acid (RA) in vitro. We then assessed changes in the expression of Notch signaling-related molecules and some miRNAs (9, 34a, 200b), which exert their regulation by targeting Notch signaling. Moreover, we used a γ-secretase inhibitor (DAPT) to disturb Notch signaling. Data revealed that the levels of the Notch signaling-related molecules decreased, whereas those miRNAs increased, during this differentiation process. Inhibition of Notch signaling accelerated the formation of the neural rosette structures and the expression of NSC and mature neurocyte marker genes. This suggests that Notch signaling negatively regulated the neuralization of human iPSCs, and that this process may be regulated by some miRNAs.

miR-210 activates notch signaling pathway in angiogenesis induced by cerebral ischemia.

The compensatory angiogenesis that occurs after cerebral ischemia increases blood flow to the injured area and limits extension of the ischemic penumbra. In this way, it improves the local blood supply. Fostering compensatory angiogenesis is an effective treatment for ischemic cerebrovascular disease. However, angiogenesis in the adult organism is a complex, multi-step process, and the mechanisms underlying the regulation of angiogenesis are not well understood. Although Notch signaling reportedly regulates the vascularization process that occurs in ischemic tissues, little is known about the role of Notch signaling in the regulation of ischemia-induced angiogenesis after ischemic stroke. Recent research has indicated that miR-210, a hypoxia-induced microRNA, plays a crucial role in regulating the biological processes that occur in blood vessel endothelial cells under hypoxic conditions. This study was undertaken to investigate the role of miR-210 in regulating angiogenesis in response to brain ischemia injury and the role of the Notch pathway in the body's response. We found miR-210 to be significantly up-regulated in adult rat ischemic brain cortexes in which the expression of Notch1 signaling molecules was also increased. Hypoxic models of human umbilical vein endothelial cells (HUVE-12) were used to assess changes in miR-210 and Notch1 expression in endothelial cells. Results were consistent with in vivo findings. To determine the molecular mechanisms behind these phenomena, we transfected HUVE-12 cells with miR-210 recombinant lentiviral vectors. We found that miR-210 overexpression caused up-regulation of Notch1 signaling molecules and induced endothelial cells to migrate and form capillary-like structures on Matrigel. These data suggest that miR-210 is involved in the regulation of angiogenesis in response to ischemic injury to the brain. Up-regulation of miR-210 can activate the Notch signaling pathway, which may contribute to angiogenesis after cerebral ischemia.

Upregulation of microRNA-210 regulates renal angiogenesis mediated by activation of VEGF signaling pathway under ischemia/perfusion injury in vivo and in vitro.

BACKGROUND: MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs that regulate gene expression and function, but little is known about regulation of miRNAs in the kidneys under normal or pathologic conditions. Here, we sought to investigate the potential involvement of miRNAs in renal ischemia/reperfusion (I/R) injury and angiogenesis and to define some of the miRNAs possibly associated with renal angiogenesis. METHODS AND RESULTS: Male Balb/c mice were subjected to a standard renal I/R. CD31 immunostaining indicated a significant increase of microvessels in the ischemic region. VEGF and VEGFR2 expression were increased in renal I/R at both the mRNA and protein levels which were detected by qRT-PCR and Western blot, respectively. More importantly, 76 microRNAs exhibited more than 2-fold changes using Agilent microRNA microarray, which contains downregulation of 40 miRNAs and upregulation of 36 miRNAs. Upregulation of miR-210 was confirmed by qRT-PCR with prominent changes at 4 and 24 h after reperfusion. Furthermore, overexpression of miR-210 in HUVEC-12 cells enhances VEGF and VEGFR2 expression and promotes angiogenesis on Matrigel in vitro. CONCLUSION: These findings suggest miR-210 may be involved in targeting the VEGF signaling pathway to regulate angiogenesis after renal I/R injury, which provides novel insights into the angiogenesis mechanism of renal I/R injury.

Capn4 overexpression indicates poor prognosis of ovarian cancer patients.

Recent studies have shown a close correlation between Capn4 expression and the prognosis of patients with solid tumors. This study aimed to investigate clinical role of Capn4 in ovarian cancer. The expression of Capn4 in 113 ovarian cancer and 35 non-tumor tissue samples were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Capn4 expression was significantly upregulated in ovarian cancer tissues compared with non-tumor tissues (p < 0.01), and was positively correlated to FIGO stage, tumor grade and distant metastasis of ovarian cancer. Kaplan-Meier analysis indicated that patients with high Capn4 expression had shorter overall survival (HR = 1.929, 95%CI: 1.210-3.077, P= 0.006) and progress-free survival (PFS) (HR = 2.043, 95%CI: 1.276-3.271, P= 0.003). Moreover, univariate Cox regression analysis demonstrated that Capn4 overexpression was an unfavorable prognostic factor for ovarian cancer (HR = 2.819, 95%CI: 1.365-3.645, P = 0.003). After the adjustment with age, histological type and tumor size, multivariate Cox regression analysis showed that Capn4 expression level (HR = 2.157,95%CI: 1.091-3.138, P = 0.014), distant metastasis (HR = 1.576, 95%CI: 1.025-3.012, P = 0.028), tumor grade (HR = 1.408, 95%CI: 0.687-2.884, P = 0.037), and FIGO stage (HR = 1.791, 95%CI: 1.016-3.158, P=0.036) were independent poor prognostic indicators for ovarian cancer. In conclusion, Capn4 has the potential as a new prognostic marker for patients with ovarian cancer.

Biological characteristics of human-urine-derived stem cells: potential for cell-based therapy in neurology.

Stem cells in human urine have gained attention in recent years; however, urine-derived stem cells (USCs) are far from being well elucidated. In this study, we compared the biological characteristics of USCs with adipose-derived stem cells (ASCs) and investigated whether USCs could serve as a potential cell source for neural tissue engineering. USCs were isolated from voided urine with a modified culture medium. Through a series of experiments, we examined the growth rate, surface antigens, and differentiation potential of USCs, and compared them with ASCs. USCs showed robust proliferation ability. After serial propagation, USCs retained normal karyotypes. Cell surface antigen expression of USCs was similar to ASCs. With lineage-specific induction factors, USCs could differentiate toward the osteogenic, chondrogenic, adipogenic, and neurogenic lineages. To assess the ability of USCs to survive, differentiate, and migrate, they were seeded onto hydrogel scaffold and transplanted into rat brain. The results showed that USCs were able to survive in the lesion site, migrate to other areas, and express proteins that were associated with neural phenotypes. The results of our study demonstrate that USCs possess similar biological characteristics with ASCs and have multilineage differentiation potential. Moreover USCs can differentiate to neuron-like cells in rat brain. The present study shows that USCs are a promising cell source for tissue engineering and regenerative medicine.

Human induced pluripotent stem cell-derived neural stem cells survive, migrate, differentiate, and improve neurologic function in a rat model of middle cerebral artery occlusion.

INTRODUCTION: Stroke is a major cause of permanent neurologic damage, with few effective treatments available to restore lost function. Induced pluripotent stem cells (iPSCs) have the potential to generate all cell types in vitro and can be generated from a stroke patient. Therefore, iPSCs are attractive donor sources of genetically identical "patient-specific" cells to hold promise in therapy for stroke. In the present study, we established a four-stage culture system by using serum-free medium and retinoic acid (RA) to differentiate iPSCs into neural stem cells (NSCs) effectively and stably. Our hypothesis was that iPSC-derived NSCs would survive, migrate, and differentiate in vivo, and improve neurologic function after transplantation into the brains of rats with ischemic stroke. METHODS: Human iPSCs (iPS-S-01) and human ESCs (HuES17) were used to differentiate into NSCs by using our four-stage culture system. iPSCs and differentiated NSCs were characterized by immunocytochemistry staining and reverse transcription-polymerase chain reaction (RT-PCR) analysis. After establishment of focal cerebral ischemia with occlusion of the middle cerebral artery (MCA) and cell transplantation, animals were killed at 1 week and 2 weeks to analyze survival, migration, and differentiation of implanted cells in brain tissue. Animal behavior was evaluated via rope grabbing, beam walking, and Morris water maze tests. RESULTS: iPSCs were efficiently induced into NSCs by using a newly established four-stage induction system in vitro. iPSCs expressed pluripotency-associated genes Oct4, Sox2, and Nanog before NSC differentiation. The iPSC-derived NSCs spontaneously differentiated into neurons and astrocytes, which highly express ß-tubulin and glial fibrillary acidic protein (GFAP), respectively. On transplantation into the striatum, CM-DiI labeled iPSC-derived NSCs were found to migrate into the ischemia area at 1 week and 2 weeks, and animal-function recovery was significantly improved in comparison with control groups at 3 weeks. CONCLUSIONS: The four-stage induction system is stable and effective to culture, differentiate, and induce iPSCs to NSCs by using serum-free medium combined with retinoic acid (RA). Implanted iPSC-derived NSCs were able to survive, migrate into the ischemic brain area to differentiate into mature neural cells, and seem to have potential to restore lost neurologic function from damage due to stroke in a rat model.

[Regulatory effects of lanthanum chloride on the activation of nuclear factor kappa B inhibitor kinase beta induced by tumor necrosis factor alpha].

OBJECTIVE: To investigate the regulatory effects of lanthanum chloride (LaCl3) on the activation of nuclear factor kappa B inhibitor (IκB) kinase beta (IKKß) induced by tumor necrosis factor alpha (TNF-α). METHODS: (1) Hela cells were cultured routinely in vitro. One portion of cells were collected and divided into TNF-α group (cultured with serum-free RMPI 1640 medium containing 20 ng/mL TNF-α for 30 min), low-dose LaCl3 + TNF-α group, moderate-dose LaCl3 + TNF-α group, high-dose LaCl3 + TNF-α group, LaCl3 group (cultured with serum-free RMPI 1640 medium containing 100 µmol/L LaCl3 for 30 min), and control group (cultured with serum-free RMPI 1640 medium for 30 min) according to the random number table. Cells in low-dose LaCl3 + TNF-α group, moderate-dose LaCl3 + TNF-α group, high-dose LaCl3 + TNF-α group were first cultured with serum-free RMPI 1640 medium containing 5, 25, 100 µmol/L LaCl3 for 4 h, and then stimulated with serum-free RMPI 1640 medium containing 20 ng/mL TNF-α for 30 min. There were 3 samples in each group. Cells were collected for detection of intracellular location of NF-κB/p65 protein by immunofluorescence staining. (2) Another portion of cells were collected and divided into TNF-α group, low-dose LaCl3 + TNF-α group, moderate-dose LaCl3 + TNF-α group, high-dose LaCl3 + TNF-α group, and control group with the same treatment as above. There were 3 samples in each group. The protein levels of NF-κB/p65 in nuclei, and the protein levels of IκBα, phosphorylated IκBα (p-IκBα) as well as IKKß and phosphorylated IKKß (p-IKKß) in cytoplasm were determined by Western blotting. The binding activity between NF-κB/p65 in the nuclear and target gene was determined by NF-κB/p65 transcription factor kit (denoted as absorption value). Data were processed with analysis of variance or LSD-t test. RESULTS: (1) High expression of NF-κB/p65 was observed in cytoplasm of control group. High expression of NF-κB/p65 was observed in nuclei of TNF-α group. The expression of NF-κB/p65 in cytoplasm of LaCl3 group was lower than that of control group. In groups treated with LaCl3 and TNF-α, NF-κB/p65 expression levels in nuclei and cytoplasm were decreased along with the increase in the concentration of LaCl3, which were all lower than those in TNF-α group. (2) There was certain amount of NF-κB/p65 protein expressed in nuclei of control group. The expression of NF-κB/p65 protein in nuclei of TNF-α group was higher than that of control group. In groups treated with LaCl3 and TNF-α, the expressions of NF-κB/p65 protein in nuclei were decreased along with an increase in the concentration of LaCl3. The level of IκBα in TNF-α group was significantly decreased but that of p-IκBα increased as compared with those in control group. Along with the increase in the concentration of LaCl3, the levels of IκBα gradually increased and the levels of p-IκBα gradually decreased in groups treated with LaCl3 and TNF-α. There were no statistical differences in expression levels of IKKß among the 5 groups. The expression of p-IKKß could be hardly observed in control group, but it was obviously increased in TNF-α group. The expression levels of p-IKKß in groups treated with LaCl3 and TNF-α were gradually decreased along with the increase in the concentration of LaCl3. The absorption value in TNF-α group was 0.39 ± 0.03, which was higher than that in control group (0, t = -7.23, P<0.01). The absorption values in low-dose LaCl3 +TNF-α group, moderate-dose LaCl3 + TNF-α group, and high-dose LaCl3 +TNF-α group were respectively 0.17 ± 0.03, 0.15 ± 0.03, and 0, which were obviously lower than that in TNF-α group (with t values respectively -6.54, -5.92, -7.23, P values all below 0.01). CONCLUSIONS: LaCl3 can block the activation of NF-κB signaling pathway by blocking the phosphorylation of IKKß of Hela cells.

The suppressive effects of lanthanum on the production of inflammatory mediators in mice challenged by LPS.

Lanthanide ions have been proven to have various biologic effects. Lanthanum with extremely active physical and chemical property was evidenced to possess antibacterial and immune adjustment effects. In the present study, the anti-inflammatory effects of lanthanum chloride (LaCl(3)) on lipopolysaccharide (LPS)-challenged mice were examined in vivo and in vitro. The results indicated that LaCl(3) can greatly decrease the secretion of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1ß as well as TNF-α mRNA expression in the mice challenged with LPS. To clarify the mechanism involved, the effects of LaCl(3) on the activation of nuclear factor (NF)-κB were examined both in liver and in peritoneal macrophages. The LPS-induced activation of NF-κB was significantly blocked by LaCl(3). These findings demonstrate that the inhibition of the LPS-induced inflammatory media, such as TNF-α and IL-1ß, by LaCl(3), is due to the inhibition of NF-κ B activation.

[Inhibitory effect of lanthanum chloride on the expression of inducible nitric oxide synthase in RAW264.7 macrophages induced by lipopolysaccharide].

OBJECTIVE: To explore the influence of lanthanum chloride (LaCl3) on inducible nitric oxide synthase (iNOS) expression in RAW264.7 macrophages with lipopolysaccharide (LPS) induction, and to investigate its possible mechanisms. METHODS: The RAW264.7 macrophages were randomly divided into four groups: i. e, control group (without treatment), LaCl3 group (with treatment of 2.5 micromol/L of LaCl3 for 24 hrs), LaCl3 + LPS group (with treatment of 2.5 micromol/L LaCl3 for 24h), and LPS group (with treatment of 1 mg/L LPS for 24 hrs). The iNOS protein expression was measured by immunofluorescence and Western blot. iNOS gene expression was assayed by reverse transcription-polymerase chain reaction (RT-PCR). NO production in culture supernatant was assayed by nitrate reductase method. RESULTS: Immunofluorescence analysis showed that iNOS was located mainly in the cytoplasm. RAW264.7 cells with overexpression of iNOS accounted for 44.4%, which was obviously higher than that in LaCl3 + LPS group (11.8%, P < 0.05). There was a faint signal of FITC-labeled green tint in control group or LaCl3 group. The iNOS mRNA and protein expression, and the NO content in LPS group were significantly higher than those in control, LaCl3, and LaCl3 + LPS groups (P < 0.05). CONCLUSION: LaCl3 can suppress LPS-induced iNOS overexpression at mRNA and protein level and reduce NO production, indicating that LaCl3 can antagonize the excessive activation of iNOS induced by LPS.

[Effects of lanthanum on inhibition of lipopolysaccharide induced NF-kappaB activation].

OBJECTIVE: To investigate the influence of lanthanum on lipopolysaccharide (LPS) induced NF-KB activation in murine peritoneal macrophage. METHODS: Peritoneal macrophages were isolated and cultured by routine method, and randomly divided into 5 groups: i. e, control group, LPS group (with LPS stimulation for 30 min), La3+ group (with 2.5 micromol/L La3+ group for 30 min) , La3+ + LPS group( with 1 microg/ml LPS stimulation for 30 min after 30 min incubation with DMEM-F12 containing 2.5 microM of lanthanum.) ; La3+/LPS group (with 2.5 microM of lanthanum stimulation for 30 min, and then with 1 microg/ml of LPS for another 30 min after lanthanum was removed. The location of NF-kappaB p65 subunit (NF-kappaB/p65) in Mphi was detected by immunofluorescence and fluorescence microscope. The binding activity of NF-kappaB/p65 with DNA in nuclei was detected by TransAMTM NF-kappaB/p65 Transcription Factor assay kit. Meanwhile, the expression of NF-kappaB/p65 in nuclei, as well as IkappaBalpha in cytoplasm was measured by Western blotting. TNF-alpha content in culture supernatant were detected by ELISA. RESULTS: (1) The green fluorescence in control, La3+, La3+ LPS and La+/LPS groups was mainly located in cytoplasm, while that in LPS group was located in nuclei. The fluorescent intensity in LPS group was (116 +/- 14), which was obviously higher than that in other 4 groups (42 +/-7,73 +/-30,48 +/- 11 and 67 +/- 19, respectively, P <0.01). (2) The IkappaBalpha protein level in cytoplasm in control (0.048 +/- 0.027), La3+ group (0.062 +/- 0.049), La3+ + LPS group (0.066 +/-0.031) and La3+/LPS group (0.108 +/- 0.017) was significantly lower than that in LPS group (0.435 +/-0.066, P <0.01). (3) The expression and activation of nucleus p65 protein in Mphi in LPS group was obviously higher than the other 4 groups, but changes in the IkappaBalpha expression between LPS group and other 4 groups was of controversy. (4) TNFalpha level in the culture supernatant in La3+ group was lower than that in control group ( P < 0.05) and below the detection limit (25 pg/ml). Moreover, it in La3+ + LPS group and La3*/LPS group was lower than that in LPS group (P <0.01), but higher than that in control group. CONCLUSION: LPS can activate the nucleus translocation of NF-kappaB/p65 in Mphi of mice, increase NF-KB/p65 expression and activity, but reduce IkappaBalpha protein expression, which lead to increase of TNFalpha secretion. Lanthanum can inhibit lipopolysaccharide induced NF-kappaB activation.