This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA (shRNA) targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside (PAN)-induced podocyte injury. Two DNA sequences containing the small hairpin structure targeting TRPC6 were designed, synthesized and then inserted into the green fluorescence protein (GFP)-contained plasmids (pGC) to establish the plasmids pGCsi-TRPC6A and pGCsi-TRPC6B. Plasmids expressing scrambled shRNA were used as negative control and named pGCsi-NC. These plasmids were transfected into a conditionally immortalized murine podocyte cell line by using liposome. Flow cytometry was used to examine the transfection efficiency. TRPC6 mRNA and protein expression levels were detected by RT-PCR and Western blotting. Cultured podocytes were divided into four groups: control group, PAN treatment group, PAN+TRPC6 shRNA transfected group and PAN+scrambled shRNA transfected group. The paracelluar permeability to BSA was evaluated by Millicell-PCF Inserts and cell viability was measured by the trypan blue assay. Immunofluorescent assay was used to observe the distribution of α-actinin-4 and α-tubulin. The results showed that the transfection efficiency of the shRNA expression vector was about 45%. Expression levels of TRPC6 mRNA and protein were downregulated after transfection with pGCsi-TRPC6A and pGCsi-TRPC6B. Knocking down TRPC6 gene could effectively reverse the PAN-induced increase in the paracelluar permeability to BSA. The distribution of α-actinin-4 and α-tubulin was disrupted after treatment with PAN, which was reversed by knocking down TRPC6 gene. It was concluded that knocking down TRPC6 gene could effectively prevent podocytes from the permeability increase induced by PAN, which may be related to the regulation of podocyte cytoskeleton.
Animals ; Cell Membrane Permeability ; drug effects ; physiology ; Cell Survival ; drug effects ; physiology ; Cells, Cultured ; Gene Knockdown Techniques ; Mice ; Mice, Knockout ; Podocytes ; drug effects ; physiology ; Puromycin Aminonucleoside ; pharmacology ; TRPC Cation Channels ; genetics ; metabolism

This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA (shRNA) targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside (PAN)-induced podocyte injury. Two DNA sequences containing the small hairpin structure targeting TRPC6 were designed, synthesized and then inserted into the green fluorescence protein (GFP)-contained plasmids (pGC) to establish the plasmids pGCsi-TRPC6A and pGCsi-TRPC6B. Plasmids expressing scrambled shRNA were used as negative control and named pGCsi-NC. These plasmids were transfected into a conditionally immortalized murine podocyte cell line by using liposome. Flow cytometry was used to examine the transfection efficiency. TRPC6 mRNA and protein expression levels were detected by RT-PCR and Western blotting. Cultured podocytes were divided into four groups: control group, PAN treatment group, PAN+TRPC6 shRNA transfected group and PAN+scrambled shRNA transfected group. The paracelluar permeability to BSA was evaluated by Millicell-PCF Inserts and cell viability was measured by the trypan blue assay. Immunofluorescent assay was used to observe the distribution of α-actinin-4 and α-tubulin. The results showed that the transfection efficiency of the shRNA expression vector was about 45%. Expression levels of TRPC6 mRNA and protein were downregulated after transfection with pGCsi-TRPC6A and pGCsi-TRPC6B. Knocking down TRPC6 gene could effectively reverse the PAN-induced increase in the paracelluar permeability to BSA. The distribution of α-actinin-4 and α-tubulin was disrupted after treatment with PAN, which was reversed by knocking down TRPC6 gene. It was concluded that knocking down TRPC6 gene could effectively prevent podocytes from the permeability increase induced by PAN, which may be related to the regulation of podocyte cytoskeleton.

To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved, 36 male Sprague-Dawley rats were randomly divided into control group, adriamycin nephropathy (AN) group and eplerenone-treated group (100 mg·kg(-1)·d(-1) eplerenone). Blood pressure, 24-h urinary protein, serum potassium, sodium and creatinine were measured 28 days after adriamycin injection (a single tail intravenous injection of 6.5 mg/kg adriamycin). The morphological changes of renal tissues were observed by light and electron microscopy. Immunohistochemistry and Western blotting were performed to examine the expression of TGF-β(1) and desmin in renal cortex. The results showed that 28 days after adriamycin injection, there were no significant changes in the level of serum potassium, sodium, creatinine concentrations and blood pressure values in the rats of the three groups. Meanwhile, the 24-h proteinuria excretion in the AN group was significantly higher than that in the control group (P<0.01), but that in the eplerenone-treated group was substantially reduced when compared with that in the AN group (P<0.05). Mild mesangial cell proliferation and matrix expansion, diffuse deformation and confluence of foot processes in podocytes were found in the AN group. By contrast, rats in the eplerenone-treated group exhibited obvious attenuation of these morphological lesions. The protein expression of TGF-β(1) and desmin in the AN group was markedly up-regulated in contrast to that in the control group (P<0.01), whereas that in the eplerenone-treated group was much lower than in the AN group (P<0.05). It was concluded that eplerenone may ameliorate the proteinuria and the development of pathological alteration in adriamycin-induced nephropathy presumably via the inhibition of cytokine release, and restore the morphology of podocytes independent of its blood pressure-lowing effects.

To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved,36 male Sprague-Dawley rats were randomly divided into control group,adriamycin nephropathy (AN) group and eplerenone-treated group (100 mg·kg-1·d-1 eplerenone).Blood pressure,24-h urinary protein,serum potassium,sodium and creatinine were measured 28 days after adriamycin injection (a single tail intravenous injection of 6.5 mg/kg adriamycin).The morphological changes of renal tissues were observed by light and electron microscopy.lmmunohistochemistry and Western blotting were performed to examine the expression of TGF-β1 and desmin in renal cortex.The results showed that 28 days after adriamycin injection,there were no significant changes in the level of serum potassium,sodium,creatinine concentrations and blood pressure values in the rats of the three groups.Meanwhile,the 24-h proteinuria excretion in the AN group was significantly higher than that in the control group (P＜0.01),but that in the eplerenone-treated group was substantially reduced when compared with that in the AN group (P＜0.05).Mild mesangial cell proliferation and matrix expansion,diffuse deformation and confluence of foot processes in podocytes were found in the AN group.By contrast,rats in the eplerenone-treated group exhibited obvious attenuation of these morphological lesions.The protein expression of TGF-β1 and desmin in the AN group was markedly up-regulated in contrast to that in the control group (P＜0.01),whereas that in the eplerenone-treated group was much lower than in the AN group (P＜0.05).It was concluded that eplerenone may ameliorate the proteinuria and the development of pathological alteration in adriamycin-induced nephropathy presumably via the inhibition of cytokine release,and restore the morphology of podocytes independent of its blood pressure-lowing effects.

To investigate the effects of ischemia-reperfusion on the levels of nitric oxide and nitric oxide synthase isoforms (nNOS and iNOS), rat organotypic hippocampus slice were cultured in vitro and subjected to ischemia by oxygen-glucose deprivation (OGD) for 30 min and then placed in the normal culture condition. The ischemia-reperfusion produced a time-dependent increase in nitrite levels in the culture medium. Reverse transcriptional-polymerase chain reaction showed augmented levels of mRNA for both nNOS and iNOS when compared with control at 12 h and remained increase at 36 h after OGD (P < 0.05). The protein levels of both nitric oxide synthase isoforms increased significantly as determined by Western Blot. OGD also caused neurotoxicity in this model as revealed by the elevated lactate dehydrogenase (LDH) efflux into the incubation solution. The results suggest that organotypic hippocampus slice is a useful model in studying ischemia-reperfusion brain injury. NO and NOS may play a critical role in the ischemia-reperfusion brain damage in vitro.
Animals, Newborn ; Cell Hypoxia ; Hippocampus/cytology ; Hippocampus/*metabolism ; Nitric Oxide/*metabolism ; Nitric Oxide Synthase Type I/*metabolism ; Nitric Oxide Synthase Type II/*metabolism ; RNA, Messenger/metabolism ; Rats, Sprague-Dawley ; Reperfusion Injury/*metabolism ; Tissue Culture Techniques

The effect of electroacupuncture (EA) on TRPM7 mRNA expression of focal cerebral ischemia in rats and further the role of EA in the relationship between TRPM7 and trkA pathway was investigated. Thirty SD rats were randomly divided into 5 groups : normal group, ischemia/reperfusion group, EA treated group (ischemic rats with EA treatment), TE infusion group (ischemic rats with EA treatment and TE buffer infusion), AS-ODN group (ischemic rats with EA treatment and antisense trkA oligonucleotide infusion). The stroke animal model was established by the modified method of middle cerebral artery occlusion. Antisense trkA oligonucleotide that blocked NGFs effects was injected into cerebroventricle before EA. The TRPM7 mRNA was detected by RT-PCR method. The results showed that there were low TRPM7 mRNA levels in cortex and hippocampus in normal group. Compared with normal group, TRPM7 mRNA expression was increased significantly in ischemia/reperfusion group (P<0.05). A significant reduction in the expression of TR-PM7 mRNA was found in EA treated group in contrast to ischemia/reperfusion group (P<0.05). The expression of TRPM7 mRNA in AS-ODN group was remarkably increased compared with EA treated group and TE infusion group (P<0.05). The results indicated that TRPM7 channels in the ischemic cortex and hippocampus in rats might play a key role in ischemic brain injury. EA could reverse the overexpression of TRPM7 in cerebral ischemia/reperfusion rats. And the inhibitory effect of EA on TRPM7 channels might be through trkA pathway.

Summary: The effect of electroacupuncture (EA) on TRPM7 mRNA expression of focal cerebral ischemia in rats and further the role of EA in the relationship between TRPM7 and trkA pathway was investigated. Thirty SD rats were randomly divided into 5 groups : normal group, ischemia/reperfusion group, EA treated group (ischemic rats with EA treatment), TE infusion group (ischemic rats with EA treatment and TE buffer infusion),AS-ODN group (ischemic rats with EA treatment and antisense trkA oligonucleotide infusion). The stroke animal model was established by the modified method of middle cerebral artery occlusion. Antisense trkA oligonucleotide that blocked NGF's effects was injected into cerebroventricle before EA. The TRPM7 mRNA was detected by RT-PCR method. The results showed that there were low TRPM7 mRNA levels in cortex and hippocampus in normal group. Compared with normal group, TRPM7 mRNA expression was increased significantly in ischemia/reperfusion group (P<0.05). A significant reduction in the expression of TRPM7 mRNA was found in EA treated group in contrast to ischemia/reperfusion group (P<0.05). The expression of TRPM7 mRNA in AS-ODN group was remarkably increased compared with EA treated group and TE infusion group (P<0.05). The results indicated that TRPM7 channels in the ischemic cortex and hippocampus in rats might play a key role in ischemic brain injury. EA could reverse the overexpression of TRPM7 in cerebral ischemia/reperfusion rats. And the inhibitory effect of EA on TRPM7 channels might be through trkA pathway.

In order to explore the role of connective tissue growth factor (CTGF) in the pathogenesis of renal tubulointerstitial fibrosis, 48 Wistar rats were randomly divided into sham-operated and unilateral ureteral obstruction (UUO) group. On the postoperative day 1, 3, 7 and 14, the rats were killed and the kidneys were removed. The renal tubulointerstitial injury index was evaluated according to the MASSON staining. The mRNA levels of CTGF, transforming growth factor-β1(TGF-β1), collagen Ⅰ (col Ⅰ ), and plasminogen activator inhibitor-1 (PAI-1) were detected using reverse transcriptional-polymerase chain reaction (RT-PCR). Immunohistochemistry was performed to evaluate the protein expression of the above factors, and the relations among them were analyzed. Quantitative expression of CTGF protein in the kidneys was also assessed using Western blot. The results showed that TGF-β1 mRNA level was increased at first day after UUO, followed by a marked elevation of CTGF mRNA level, which began to increase 3 days after UUO (P＜0.01). With the progression of the disease, the mRNA expression of CTGF, col Ⅰ and PAI-1 was increased progressively. Immunohistochemistry revealed that the CTGF protein expression was significantly increased in fibrotic areas and tubular epithelial cells 3 days after UUO. On the post-UUO day 7, the protein level of CTGF was positively related to the renal tubulointerstitial injury index (r =0.62, P＜0.01), the expression of TGF-β1 (r=0.85, P＜0.01), col Ⅰ (r=0.78, P＜0.01),and PAI-1(r=0.76, P＜0.01). Upon Western blot analysis, CTGF protein expression began to increase 3 days after UUO, and appeared progressively throughout the time course (P＜0. 01, as compared with sham-operated group). It is concluded that CTGF can be induced by TGF-β and mediate various profibrotic actions of this cytokine, such as increasing extracellular matrix (ECM)synthesis and decreasing ECM degradation. The increased expression of CTGF may play a crucial role in the development and progression of tubulointerstitial fibrosis.

To investigate the effects of ischemia-reperfusion on the levels of nitric oxide and nitric oxide synthase isoforms (nNOS and iNOS), rat organotypic hippocampus slice were cultured in vitro and subjected to ischemia by oxygen glucose deprivation (OGD) for 30 min and then placed in the normal culture condition. The ischemia-reperfusion produced a time-dependent increase in nitrite levels in the culture medium. Reverse transcriptional-polymerase chain reaction showed augmented levels of mRNA for both nNOS and iNOS when compared with control at 12 h and remained increase at 36 h after OGD (P＜0.05). The protein levels of both nitric oxide synthase isoforms increased significantly as determined by Western Blot. OGD also caused neurotoxicity in this model as revealed by the elevated lactate dehydrogenase (LDH) efflux into the incubation solution. The results suggest that organotypic hippocampus slice is a useful model in studying ischemia-reperfusion brain injury. NO and NOS may play a critical role in the ischemia-reperfusion brain damage in vitro.

The aim of this study was to express and purify human histydyl-tRNA synthetase related gene and to prepare its polyantibody. The open reading frame was amplified by PCR, and then recombined into prokaryotic expression vector pQE30 and transformed into E. coli M15 for expression. The expressed products were induced by IPTG after the reconstructed pQE30 was transferred into M15. After purified by Ni affinity chromatography, the product was identified to be a single band by SDS-PAGE. The rabbits were inoculated with purified products. High-titer polyantibody was successfully prepared. Highly-purified expression product and prepared polyantibody may provide a good basis for further study.
Antibodies ; genetics ; immunology ; Escherichia coli ; genetics ; metabolism ; Histidine-tRNA Ligase ; biosynthesis ; genetics ; immunology ; Humans ; Open Reading Frames ; genetics ; Prokaryotic Cells ; metabolism