Notoginsenoside R_1 interferes with renal oxidative stress and Nrf2/HO-1 signaling pathway to alleviate kidney injury in mice with IgA nephropathy and its mechanism / 中国中药杂志

The purpose of this study was to investigate the effect of notoginsenoside R_1(NGR_1) on alleviating kidney injury by regulating renal oxidative stress and the Nrf2/HO-1 signaling pathway in mice with IgA nephropathy(IgAN) and its mechanism. The mouse model of IgAN was established using a variety of techniques, including continuous bovine serum albumin(BSA) gavage, subcutaneous injections of carbon tetrachloride(CCl_4) castor oil, and tail vein injections of lipopolysaccharide(LPS). After successful modeling, mice with IgAN were randomly separated into a model group, low, medium, and high-dose NGR_1 groups, and a losartan group, and C57BL6 mice were utilized as normal controls. The model and normal groups were given phosphate buffered saline(PBS) by gavage, the NGR_1 groups were given varying dosages of NGR_1 by gavage, and the losartan group was given losartan by gavage for 4 weeks. The 24-hour urine of mice was collected after the last administration, and serum and kidney tissues of mice were taken at the end of the animal experiment. Then urine red blood cell count(URBCC), 24-hour urine protein(24 h protein), serum creatinine(Scr), and blood urea nitrogen(BUN) levels were measured. The enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of galactose-deficient IgA1(Gd-IgA1), kidney injury molecule 1(Kim-1), and neutropil gelatinase-associated lipocalin(NGAL) in the mouse serum. The assay kits were used to detect the levels of malondialdehyde(MDA) and superoxide dismutase(SOD), and immunofluorescence(IF) was used to detect the expression level of glutathione peroxidase 4(GPX4) in the mesangial region. Western blot was used to detect the protein expression of nuclear transcription factor E2 related factor 2(Nrf2)/heme oxygenase 1(HO-1) signaling pathway in the renal tissue. Hematoxylin-eosin(HE) staining was used to observe pathological alterations in the glomerulus of mice. The results revealed that, as compared with the model group, the serum Gd-IgA1 level, URBCC, 24 h protein level, renal damage markers(Kim-1 and NGAL) in the high-dose NGR_1 group decreased obviously and renal function indicators(BUN, Scr) improved significantly. The activity of SOD activity and expression level of GPX4 increased significantly in the high-dose NGR_1 group, whereas the expression level of MDA reduced and protein expression levels of Nrf2 and HO-1 increased. Simultaneously, HE staining of the renal tissue indicated that glomerular damage was greatly decreased in the high-dose NGR_1 group. In conclusion, this study has clarified that NGR_1 may alleviate the kidney injury of mice with IgAN by activating the Nrf2/HO-1 signaling pathway, improving antioxidant capacity, and reducing the level of renal oxidative stress.

Primary study on the effect of glucose on mouse CD4+ T cell differentiation and its mechanism / 上海交通大学学报（医学版）

Objective :To study the effect of glucose on mouse CD4+ T cell differentiation. Methods :Mouse naïve CD4+ T cells cultured in the regulatory T cell (Treg), Th1, Th17 or Th2 differention condition were treated with different concentrations of glucose for 5 days. Treg, Th1, Th17 or Th2 percentages were measured by flow cytometry. Quantitative real-time PCR was used to detect the gene expressions of related cytokines and transcriptional factors. Results :The proportions of Treg and Th2 as well as the gene expressions of transforming growth factor-β, interleukin-4 (IL-4) and IL-13, and transcriptional factors, Foxp3 (forkhead box P3) and Gata3 (GATA binding protein 3), were increased significantly with the treatment of increasing concentration of glucose. On the contrary, with the glucose treatment, the percentages of Th1 and Th17 were reduced, and the gene expressions of the related cytokines and cytokine receptors, such as interferon-γ, IL-17A, IL-17F, IL-22 and IL-23R, and the related transcriptional factors, Tbx21 (T-box transcription factor 21) and RORC (RAR related orphan receptor C), were decreased consistently. Conclusion :Glucose promotes Treg and Th2 differentiation while inhibits Th1 and Th17 differentiation in vitro.

Effect of HIPK2 gene on viability, apoptosis and JAK2/STAT3 signaling pathway in NRK-52E renal tubular epithelial cells induced by hypoxia and reoxygenation / 中国病理生理杂志

AIM:To investigate the effect of homeodomain-interacting protein kinase 2 (HIPK2) on the viabi-lity, apoptosis and JAK2/STAT3 signaling pathway in NRK-52E renal tubular epithelial cells induced by hypoxia and reox-ygenation (H/R). METHODS:HIPK2 small interfering RNA (siRNA) was transfected into NRK-52E cells by Lipo-fectamineTM 2000, and normal control group (control group) and negative control group (HIPK2-NC group) were set up. After H/R, the cell viability was measured by CCK-8 assay, the apoptotic rate and Ca2+ fluorescence intensity were ana-lyzed by flow cytometry, and the protein levels of Ki67, cleaved caspase-3, caspase-12, Bcl-2, Bax, p-JAK2 and p-STAT3 were determined by Western blot. RESULTS:Compared with control group, the protein expression of HIPK2 in the NRK-52E cells was significantly decreased after transfection with HIPK2 siRNA (P<0.05). Compared with control group, the cell viability and the protein expression of Ki67 and Bcl-2 in H/R group were also significantly decreased, and the apoptotic rate, the Ca2+ fluorescence intensity and the protein levels of cleaved caspase-3, caspase-12, Bax, p-JAK2 and p-STAT3 were significantly increased (P<0.05). Compared with H/R group, the cell viability and the protein expression of Ki67 and Bcl-2 in HIPK2-siRNA+H/R group were significantly increased, while the apoptotic rate, the Ca2+ fluorescence inten-sity and the protein levels of cleaved caspase-3, caspase-12, Bax, p-JAK2 and p-STAT3 were significantly decreased (P<0.05). CONCLUSION:Inhibition of HIPK2 gene expression promotes H/R-induced growth of NRK-52E renal tubular epi-thelial cells, and reduces the apoptosis. The mechanism is related to down-regulating the JAK2/STAT3 signaling pathway.

Human placenta-derived mesenchymal stem cell transplantation provides neuroprotection against cerebral infarction in rats / 中国组织工程研究

BACKGROUND: Bone marrow mesenchymal stem cells improve neurological functional recovery from cerebral infarction, but they are a rare population in the bone marrow with difficulty in cell separation and purification. OBJECTIVE: To investigate the neuroprotective effects and the potential mechanisms of human placenta-derived mesenchymal stem cell transplantation for cerebral infarction in rats. METHODS: Totally 120 rats subjected to middle cerebral artery occlusion were randomized into treatment group and control (n=60 per group). The rats were intravenously treated with human placenta-derived mesenchymal stem cells in the treatment group or the phosphate buffer saline in the control group. Then, a modified neurological severity score was assessed at 1, 3, 7, 14 days post transplantation, and measurement of infarct volume in the ischemic brain was performed using 2,3,5-triphenyltetrazolium chloride staining at 14 days post transplantation. The anti-human specific immunostain for mitochondria in the ischemic brain was performed and the mitochondria-positive cells were counted; TUNEL immunostaining was performed and TUNEL positive cells were counted. ELISA assays for brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also performed in the ischemic brain. RESULTS AND CONCLUSION: At 1, 3, 7 and 14 days after treatment, the modified neurological severity score in the treatment group was significantly lower than that in the control group (P < 0.05). At 14 days after treatment, the infarct volume in the treatment group was significantly lower than that in the control group (P < 0.05), only few mitochondria-positive cells were present in the ischemic brain, and the number of TUNEL positive cells in the treatment group was significantly less than that in the control group (P < 0.05). At 3 and 14 days after treatment, BDNF expression levels in the treatment group were significantly higher than those in the control group (P < 0.05). At 7 and 14 days after treatment, VEGF expression levels in the treatment group were significantly higher than those in the control (P < 0.05). At 7 days after treatment, HGF expression level in the treatment group was significantly higher than that in the control group (P < 0.05). To conclude, intravenous administration of human placenta-derived mesenchymal stem cells can promote neuroprotective effects against cerebral infarction. These effects may be related to the increase of BDNF, VEGF and HGF expression and the decrease of apoptosis in the ischemic brain.

Study on the micropermeability of resin-dentin bonding interfaces with ethanol-wet bonding technique / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the micropermeability on bonding hydrophobic adhesive to dentin with ethanol-wet bonding under simulated pulp pressure.</p><p><b>METHODS</b>Twenty-four intact human third molars were used in the study. After the enamel of occlusal surfaces was removed, the molars were randomly divided into six groups. Adper Scotchbond Multi-Purpose was used in the control group; in the experimental groups, the dentin surfaces were saturated with ethanol for 20 s (group 1), 1 min (group 2), 2 min (group 3), 3 min (group 4) or with a series of increasing ethanol concentrations before application of hydrophobic adhesive (group 5). All the bonding procedures were done under simulated pulp pressure. After 24 hours, micro-tensile bond strength test were performed on the specimens. Bonding interfaces were observed under laser scanning confocal microscope (LSCM) after the pulp chamber were filled with a water-soluble fluoroprobe rhodamine B for 3 hours.</p><p><b>RESULTS</b>Compared with the control group [(38.14 ± 4.97) MPa], bond strengths in group 1 [(21.02 ± 7.23) MPa] and group 2 [(29.64 ± 3.81) MPa] were statistically lower (P > 0.05), while bond strength in group 3 [(38.40 ± 5.03) MPa], group 4 [(37.26 ± 4.68) MPa] and group 5 [(40.12 ± 5.95) MPa] were similar to the control group (P < 0.05). The images taken by LSCM showed that with extension of ethanol-wet time, the deposition of fluorescent dye in hybrid layer and along the dentinal tubules decreased gradually. Especially in group 5, only spare fluorescent dye deposition could be detected in the hybrid layer.</p><p><b>CONCLUSIONS</b>Dentin saturated with ethanol for more than 2 min before bonding hydrophobic adhesive to dentin could provide favorable bond strength and decreased the micropermeability of bonding interfaces under simulated pulp pressure.</p>

Influence of galvano-ceramic and metal-ceramic crowns on magnetic resonance imaging / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Magnetic resonance imaging (MRI) is prone to be deformed by artifacts caused by the presence of metallic materials. The aim of this study was to evaluate the artifacts from galvano-ceramic and metal-ceramic crowns in MRI, in order to analyze their influences on diagnostic interpretation of MRI.</p><p><b>METHODS</b>Galvano-ceramic and metal-ceramic crowns (Bio98, Wiron99, SP-78, BioKC97) were fabricated with the same model. All materials were imaged by means of 1.5T MRI apparatus with three different sequences, T1-weighted spin-echo (T1-weighted SE), T2-weighted spin-echo (T2-weighted SE) and Gradient echo (GE). Mean and standard deviation of distilled water signal intensity (SI) around the sample in the region of interest (500 mm2) enclosing the whole artifacts were determined, and compared for evaluation of the homogeneity of signal intensity. Images around the sample were acquired and evaluated.</p><p><b>RESULTS</b>There were statistically significant differences in the values of signal intensity between acrylic resin control and BioKC97, Wiron99 in the three sequences (P<0.001). The mean values of signal intensity for Bio98, SP-78 were significantly different from that of acrylic resin control (RE) in GE sequence (P<0.001). No difference was showed between acrylic resin control and galvano-ceramic crown (P>0.05). Images showed that the greatest artifact was a 25 mm ring with distortion in Wiron99 in GE sequence.</p><p><b>CONCLUSIONS</b>This in vitro study suggested that galvano-ceramic crown had no influence on the MRI, while metal-ceramic crowns caused moderate artifacts in the MRI. Therefore, galvano-ceramic restoration is a valuable alternative in dentistry.</p>

Angiogenesis and its regulatory factors in brain tissue of neonatal rat hypoxic-ischemic encephalopathy / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate possible mechanism of angiogenesis in brain tissue of neonatal rat hypoxic-ischemic encephalopathy (HIE).</p><p><b>METHODS</b>Forty seven-day old neonatal rats were randomly assigned to hypoxic-ischemic (Model group) or sham treatment (Sham group), each group had 20 rats. Five rats from each group were sacrificed on days 1, 3, 7 and 14 after hypoxia-ischemia. Paraffin sections of the brain were stained with anti-endothelial cell, anti-proliferating cell nuclear antigen (PCNA) or anti-vascular endothelial growth factor (VEGF) by using single or double immunohistochemistry. The brain capillary density index (BCDI), brain proliferating capillary density index (BPCDI) and the expression of VEGF were analyzed under the microscope. The expression of VEGF and hypoxia-inducible factor-1alpha (HIF-1alpha) mRNA in hypoxic-ischemic side of the brain was measured by RT-PCR.</p><p><b>RESULTS</b>BCDI around infarct brain tissue in the model group began to rise on day 3 and remained higher than that of the sham group from day 3 to day 14 [day 3: (9.80 +/- 1.05)/HPF vs. (4.90 +/- 0.66)/HPF, P < 0.01;day 14: (13.29 +/- 3.90)/HPF vs. (6.08 +/- 1.50)/HPF, P < 0.01]. Occasional proliferating capillary was found in brain tissue of normal neonatal rats. The density of proliferating brain capillary on day 3 and day 7 of Model group [(0.54 +/- 0.15)/HPF vs. (0.90 +/- 0.25)/HPF] were significantly higher than those of Sham group [(0.12 +/- 0.05)/HPF vs. (0.13 +/- 0.07)/HPF, P < 0.01]. VEGF was mainly expressed in the cytoplasm of neurons, capillary endothelial cells and pial cells. Viable neurons and endothelial cells in the infarct areas also expressed VEGF. The expression of VEGF mRNA in hypoxic-ischemic brain tissue was significantly higher than that of normal control (P < 0.01) and temporally preceded angiogenesis. The expression of VEGF mRNA at 12 hours of HIE model was significantly higher than that of normal control (1.56 +/- 0.27 vs. 0.95 +/- 0.21, P < 0.05). It reached its peak on day 1 and day 3 (1.85 +/- 0.31 vs. 1.86 +/- 0.39), significantly higher than that of normal control (P < 0.01), and decreased by day 7 and day 14, without significant difference compared with normal control (P > 0.05). The expression of HIF-1alpha mRNA was also up-regulated after hypoxic-ischemic treatment. The expression of HIF-1alpha mRNA (1.07 +/- 0.21) was significantly higher than that of normal control (0.64 +/- 0.28, P = 0.048) at 3-hour of HIE model, reached its peak on day 1 (1.73 +/- 0.42, P < 0.01), remained at high expression level on day 3 (1.44 +/- 0.36, P < 0.05) and began to decline by day 7 and day 14 when it was not significantly different from normal control.</p><p><b>CONCLUSIONS</b>Angiogenesis exists in the brain tissue of neonatal rat HIE model. Up-regulation of VEGF expression mediated by HIF-1 may play an important role in the process of angiogenesis.</p>