Upregulation of circFLNA contributes to laryngeal squamous cell carcinoma migration by circFLNA-miR-486-3p-FLNA axis.

BACKGROUND: Accumulating evidence shows that circular RNAs (circRNAs) plays vital roles in tumor progression. However, the biological functions of circRNAs in laryngeal squamous cell carcinoma (LSCC) metastasis is still unclear. METHODS: qRT-PCR was used to detect circFLNA, miRNAs and FLNA mRNA expression. Transwell assay and western blot were performed to evaluate cell migration ability and to detect FLNA, MMP2 and MLK1 protein expression, respectively. RNA pull-down analysis was used to find the binding-miRNAs of circFLNA. Luciferase reporter assay was used to examine the effect of circFLNA on miRNAs and miR-486-3p on FLNA expression. RESULTS: In this study, we confirmed that a Filamin A (FLNA)-derived hsa_circ_0092012 known as circFLNA, was upregulated in LSCC, and the higher expression of circFLNA was correlated with LSCC lymph node metastasis. Increased circFLNA facilitates LSCC cell migration ability through upregulating FLNA and MMP2 protein expression. Mechanistically, we find that circFLNA sponges miR-486-3p in LSCC cells, relieving miR-486-3p-induced repression of FLNA which promotes LSCC cell migration. Accordingly, FLNA mRNA is overexpressed in LSCC tissues and a higher FLNA level is correlated with poor survival. Dysregulation of the circFLNA/miR-486-3p/FLNA regulatory pathway contributes to LSCC migration. CONCLUSIONS: In summary, our study sheds light on the regulatory mechanism of circFLNA in LSCC migration via sponging miR-486-3p, which downregulates the FLNA protein expression. Targeting circFLNA/miR-486-3p/FLAN axis provides a potential therapeutic target for aggressive LSCC.

Construction of cDNA expression library of watermelon for isolation of ClWRKY1 transcription factors gene involved in resistance to Fusarium wilt.

Full-length cDNAs are very important for genome annotation and functional analysis of genes. The number of full-length cDNAs from watermelon remains limited. Here we report first the construction of a full-length enriched cDNA library from Fusarium wilt stressed watermelon (Citrullus lanatus Thunb.) cultivar PI296341 root tissues using the SMART method. The titer of primary cDNA library and amplified library was 2.21 x 10(6) and 2.0 x 10(10) pfu/ml, respectively and the rate of recombinant was above 85%. The size of insert fragment ranged from 0.3 to 2.0 kb. In this study, we first cloned a gene named ClWRKY1, which was 1981 bp long and encoded a protein consisting of 394 amino acids. It contained two characteristic WRKY domains and two zinc finger motifs. Quantitative real-time PCR showed that ClWRKY1 expression levels reached maximum level at 12 h after inoculation with Fusarium oxysporum f. sp. niveum. The full-length cDNA library of watermelon root tissues is not only essential for the cloning of genes which are known, but also an initial key for the screening and cloning of new genes that might be involved in resistance to Fusarium wilt.

High-fat diet causes increased serum insulin and glucose which synergistically lead to renal tubular lipid deposition and extracellular matrix accumulation.

Renal tubular lipid accumulation is associated with renal injury in the metabolic syndrome, but its mechanisms are not fully elucidated. The purpose of the present study was to investigate the exact mechanism of renal tubular lipid accumulation in the diet-induced metabolic syndrome. The in vivo experiments showed that a high-fat diet induced hyperglycaemia, hyperinsulinaemia and hypertriacylglycerolaemia, subsequent increases in sterol regulatory element binding protein-1 (SREBP-1) and transforming growth factor-ß1 (TGF-ß1), lipid droplet deposit in renal tubular cells and interstitial extracellular matrix accumulation in Wistar rats. A human renal proximal tubular epithelial cell line (HKC) was used to determine the direct role of insulin, and the results revealed that insulin induced SREBP-1, fatty acid synthase (FASN), TGF-ß1 expressions, lipid droplet and extracellular matrix deposits. Knockdown of SREBP-1 by RNA interference technology significantly inhibited FASN, TGF-ß1 up-regulation, lipid and extracellular matrix accumulation caused by insulin. In addition, we found that insulin and high glucose could synergistically increase SREBP-1, FASN, TGF-ß1 and fibronectin expressions in HKC cells. These results indicate that high-fat diet-induced increased serum insulin and glucose synergistically cause renal tubular lipid deposit and extracellular matrix accumulation via the SREBP-1 pathway.

Metabolomic analysis to detect urinary molecular changes associated with bipolar depression.

Bipolar disorder (BD) is a debilitating mental disorder with complex clinical manifestations and low diagnostic accuracy. Depressive episodes are most common in the course of BD with high comorbidity and suicide rates, which present greater clinical challenges than mania and hypomania episodes. However, there are no objective biomarkers for bipolar depression. The aim of this study was to detect urinary metabolite biomarkers that could be useful for the diagnosis of bipolar depression. Nuclear magnetic resonance spectroscopy was used to profile urine samples of patients with bipolar depression (n = 37) and healthy volunteers (n = 48). Data were analyzed using Orthogonal Partial Least Square Discriminant Analysis and t-test. Differential metabolites were identified (VIP > 1 and p < 0.05), and further analyzed using Metabo Analyst 3.0 to identify associated metabolic pathways. In total, we identified seven metabolites differentially expressed in patients with BD and healthy controls. Compared with healthy group, the levels of betaine, glycerol, hippuric acid, indole sulfate, trimethylamine oxide, and urea in urine samples of BD patients were significantly higher, while the level of inositol was significantly lower. Most of these small molecules are related to lipid metabolism and gut microbiota metabolism. These differential metabolites could provide critical insight into the pathological mechanisms of bipolar depression. The results of this study provide a meaningful reference for similar and further studies in the future.

[The expression of suppressor of cytokine signaling-1/3 in renal tubular epithelial cells induced by high glucose].

OBJECTIVE: To observe the morphologic changes and the expression of suppressor of cytokine signaling-1/3 (SOCS-1/3) in renal tubular epithelial cells induced by high glucose (HG) and to investigate their significance. METHODS: The renal tubular epithelial cell line (HKCs) cultured in vitro were divided into blank control group, HG group, and Janus kinase 2 inhibitor AG490 group. HKC of blank control group was cultured for 8 hours in 5.5 mmol/L glucose, and the other two groups were cultured in 300.0 mmol/L glucose or 300.0 mmol/L glucose+10 µmol/L AG490 for 2, 4, 6, 12, 24, 48 hours (n=6). The morphology and ultrastructure were observed with inversion microscope and electron microscope at different time points. Protein expression of SOCS-1/3 was assayed by immunocytochemistry and Western blotting; SOCS-1/3 mRNA was assessed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Under inversion microscope it was showed that 12 hours after being cultured with HG, the cells assumed a spindle-shape, with irregular protrusions, and cellular membrane became indistinguishable with prolongation of time, with increase of intracellular granules. Under the electron microscope, it was seen that there was distinct decrease in microvilli on the cell membrane and mitochondria, with an increase in rough endoplasmic reticulum. The cellular changes were not obvious in AG490 group. Furthermore, immunocytochemistry and Western blotting showed that the immunoreactivity was localized in the cytoplasm as well as in the nuclei, and there was basic expression of SOCS-1/3 protein in normal HKC (0.218±0.023, 0.337±0.009). HG was shown to induce up-regulation of the expression of SOCS-1/3 protein at 4, 6, 12, 24 hours compared with blank control group. The expression of SOCS-1 was highest at 4 hours (1.022±0.072), and that of SOCS-3 was highest at 6 hours (1.256±0.105, both P<0.01), while the expression of SOCS-1/3 protein in AG490 group was lower than that in HG group (4 hours SOCS-1: 0.589±0.167, 6 hours SOCS-3 : 0.656±0.075, both P<0.05). However, HG induced a higher expression of SOCS-1/3 mRNA at 2, 4, 6, 12 hours compared with blank control group. The expression of SOCS-1 was highest at 4 hours (1.716±0.098 vs. 0.475±0.045, P<0.05), and that of SOCS-3 was highest at 6 hours (2.848±0.116 vs. 0.749±0.086, P<0.01), while the expression of SOCS-1/3 mRNA in AG490 group was lower (4 hours SOCS-1: 0.865±0.075, 6 hours SOCS-3: 0.923±0.116, both P<0.05). CONCLUSION: HG could produce morphology and ultrastructure changes in renal tubular epithelial cell, and it induces up-regulation of SOCS-1/3 expression. These changes might be related with negative regulation of Janus kinase (JAK)/signal transducers and activators of transcription (STAT)/SOCS pathway.

[The effect of Janus kinase 2 inhibitor AG490 on renal tubular epithelial-myofibroblast transdifferentiation induced by interleukin-1ß].

OBJECTIVE: To investigate the effect of AG490, a Janus kinase 2 inhibitor, on epithelial-myofibroblast transdifferentiation induced by interleukin-1ß (IL-1ß). METHODS: Cultured human renal tubular epithelial cell line (HKCs) were divided into three groups: blank control group, IL-1ß (5 ng/ml) group and AG490 group (IL-1ß 5 ng/ml+AG490 10 µmol/L). The cells in all groups were collected at 24, 48, 72 hours after intervention. Immunocytochemistry and Western blotting analysis were used to determine the expressions of cytokeratin-18 (CK-18) and α-smooth muscle actin (α-SMA). RESULTS: The higher expression of CK-18 (1.25±0.08) and mild expression of α-SMA (0.17±0.01) were found in blank control group. In IL-1ß group, the protein level of CK-18 was gradually decreased with prolongation of stimulus (24 hours : 0.69±0.04, 48 hours: 0.52±0.03, 72 hours: 0.30±0.01), while the expression level of α-SMA was gradually increased (24 hours: 0.56±0.04, 48 hours: 1.05±0.07, 72 hours: 1.43±0.07), and the difference between blank control group and IL-1ß group was statistically significant (all P<0.05). The administration of AG490 could restore the expression of CK-18 (24 hours: 1.07±0.07, 48 hours: 0.93±0.06, 72 hours: 0.83±0.06), and inhibit the expression of α-SMA induced by IL-1ß (24 hours: 0.33± 0.01, 48 hours: 0.52±0.01, 72 hours: 0.61±0.04). There was significant difference between AG490 group and IL-1ß group (all P<0.05). The results of immunocytochemistry and that of Western blotting were identical. CONCLUSION: IL-1ß can induce the transdifferentiation of renal tubular epithelial cells, up-regulate the expression of α-SMA, induce the renal tubular epithelial cells to transform to myofibroblast, while AG490 can inhibit the effect of IL-1ß.

Upregulation of ERp57 promotes clear cell renal cell carcinoma progression by initiating a STAT3/ILF3 feedback loop.

BACKGROUND: ERp57 dysfunction has been shown to contribute to tumorigenesis in multiple malignances. However, the role of ERp57 in clear cell renal carcinoma (ccRCC) remains unclear. METHODS: Cell proliferation ability was measured by MTT and colony forming assays. Western blotting and quantitative real-time PCR (qRT-PCR) were performed to measure protein and mRNA expression. Co-immunoprecipitation (CoIP) and proximity ligation assay (PLA) were performed to detect protein-protein interaction. Chromatin immunoprecipitation (ChIP), ribonucleoprotein immunoprecipitation (RIP), and oligo pull-down were used to confirm DNA-protein and RNA-protein interactions. Promoter luciferase analysis was used to detect transcription factor activity. RESULTS: Here we found ERp57 was overexpressed in ccRCC tissues, and the higher levels of ERp57 were correlated with poor survival in patients with ccRCC. In vivo and in vitro experiments showed that ccRCC cell proliferation was enhanced by ERp57 overexpression and inhibited by ERp57 deletion. Importantly, we found ERp57 positively regulated ILF3 expression in ccRCC cells. Mechanically, ERp57 was shown to bind to STAT3 protein and enhance the STAT3-mediated transcriptional activity of ILF3. Furthermore, ILF3 levels were increased in ccRCC tissues and associated with poor prognosis. Interestingly, we revealed that ILF3 could bind to ERp57 and positively regulate its expression by enhancing its mRNA stability. Furthermore, ccRCC cell proliferation was moderated via the ERp57/STAT3/ILF3 feedback loop. CONCLUSIONS: In summary, our results indicate that the ERp57/STAT3/ILF3 feedback loop plays a key role in the oncogenesis of ccRCC and provides a potential therapeutic target for ccRCC treatment.

[Expression and clinical implication of platelet-derived growth factor-D and platelet-derived growth factor-beta in childhood IgA nephropathy].

OBJECTIVE: To investigate the clinical implication of platelet-derived growth factor (PDGF)-D and PDGF-beta in IgA nephropathy in childhood. METHODS: Forty-seven children with IgA nephropathy and 26 controls were enrolled for study, and their serum, urine and renal biopsy specimens were examined. The patients were divided into control group [including serum, urine specimens of 13 healthy children and 13 renal biopsy samples of non-IgA nephropathy in children], mild proliferation (MP) group (13 patients), focal proliferation (FP) group (19 patients), and proliferation sclerosis (PS) group (15 patients). Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were used to determine contents of PDGF-D, PDGF-beta and PDGF-B in blood, urine and renal tissues. The levels of 24-hour urinary protein excretion, serum albumin (Alb), serum blood urea nitrogen (BUN) and creatinine (Cr) were also determined. RESULTS: Compared with control group, levels of PDGF-D and PDGF-B were progressively elevated in blood and urine of IgA nephropathy children with increase in severity of glomerular damage (all P<0.01). Serum as well as urinary PDGF-D and PDGF-B levels were positively correlated with 24-hour urinary protein excretion (PDGF-D blood: r=0.546, urine: r=0.760; PDGF-B blood: r=0.634, urine: r=0.577, respectively, P<0.01), while negatively correlated with serum Alb levels in IgA nephropathy patients (PDGF-D blood: r=-0.649, urine: r=-0.528; PDGF-B blood: r=-0.613, urine: r=-0.531, respectively, P<0.01). Contents of PDGF-D and PDGF-beta in renal tissue were much higher than those of control group (P<0.01). Along with the increase in severity of glomerular pathology, their contents increased gradually. PDGF-B was only significantly expressed in renal tissue in FP group and PS group. CONCLUSION: PDGF-D might significantly enhance the development of mesangial proliferation and tubulointerstitial fibrosis. In comparison with PDGF-B, PDGF-D appears to reflect more sensitive to the severity and prognosis of IgA nephropathy.

[Expression and implication of osteopontin in renal cortex of diabetic rats].

OBJECTIVE: To investigate the expression and implication of osteopontin (OPN) in renal cortex of diabetic rats. METHODS: Experimental diabetes was reproduced in uninephrectomized rats by giving streptozotocin (STZ). The animals were divided into two groups: control group and diabetic group (each n=24). Immunohistochemistry and Western blotting were used to detect the protein expression of OPN, CD68, and proliferating cell nuclear antigen (PCNA). At the same time the mRNA expression of OPN was detected by in situ hybridization. RESULTS: Compared with control group, blood glucose, blood urea nitrogen (BUN), 24-hour urine protein quantum and quantification of OPN protein significantly increased while creatinine clearance rate (CCr) was significantly decreased in diabetic rat group 1, 2, 4 and 8 weeks after STZ injection. The protein of PCNA were also higher than that of control group 1 and 2 weeks after STZ injection (all P<0.05), and the increase in CD68 was observed at week 4 and week 8. CONCLUSION: Overexpression of OPN may be responsible for the proliferation of tubular cells at early stage of diabetic nephropathy and for the accumulation of macrophage at later stage.

[Effects of fluvastatin on the expression of Janus kinase 2/signal transducers and activators of transcription (JAK/STAT) in glomerular mesangial cells under high concentration of glucose].

OBJECTIVE: To investigate the effects of fluvastatin on activation of Janus kinase 2 (JAK2) and signal transducers and activators of transcription 1, 3 (STAT1, 3) in glomerular mesangial cells(GMCs) under high concentration of glucose. METHODS: Rat GMCs were cultured in vitro, and they were treated with glucose and fluvastatin respectively. Tyrosine phosphorylation of JAK2 (p-JAK2) expression was detected by immunoprecipitation and Western blotting analysis. The protein expressions of JAK2, STAT1, p-STAT1, STAT3 and p-STAT3 were assessed by Western blotting. The protein synthesis of transforming growth factor-beta1 (TGF-beta1) and fibronectin (FN) in the supernatants of the GMCs were determined by enzyme-linked immunoadsorbent assay (ELISA). TGF-beta1 mRNA was assessed by reverse transcription and polymerase chain reaction (RT-PCR). RESULTS: Compared with low glucose control group, the expressions of p-JAK2 (802+/-124 vs.204+/-31), p-STAT1 (2,856.6+/-337.8 vs. 617.7+/-76.2), p-STAT3 (3,049.8+/-421.3 vs. 946.7+/-141.2) and TGF-beta1 mRNA were significantly up-regulated in GMCs under high glucose medium, and the concentration of TGF-beta1 in the supernatants [(2.87+/-0.34) microg/L vs. (1.20+/-0.11) microg/L] and FN [(6.34+/-0.61) mg/L vs. (3.24+/-0.26) mg/L, both P<0.01] were higher in the supernatants. The expression levels of p-JAK2 (412+/-67), p-STAT1 (1,178.4+/-137.1), p-STAT3 (1,572.6+/-181.2) and TGF-beta1 mRNA were significantly lower in fluvastatin group than those in high glucose group. The concentration of TGF-beta1 [(1.94+/-0.27) microg/L] and FN [(4.27+/-0.33)mg/L] in the supernatants in fluvastatin group were lower than those in high glucose control group (all P<0.05). CONCLUSION: Fluvastatin can inhibit overproduction of TGF-beta1 and FN in GMCs under high concentration of glucose, the underlying mechanism may partly be attributable to its influence on phosphorylation of JAK/STAT.

[Effect of JAK/STAT pathway activation on high glucose-induced transdifferentiation in renal proximal tubular epithelial cells].

OBJECTIVE: To evaluate the effect of JAK/STAT signaling pathway activation on the transdifferentiation and secretion of transforming growth factor-beta1 (TGF-beta1) induced by high glucose in renal proximal tubular epithelial cells. METHODS: Human kidney cells (HKC) were cultured and then divided into four groups: low glucose (LG) group, high glucose (HG) group, high mannitol (LG + M) group, and HG + AG490 group. Immunoprecipitation and Western blot analysis were used to determine the expression of tryosine phosphorylated Janus kinase 2 ( p-JAK2). The protein expressions of STAT1, STAT3, p-STAT1, and p-STAT3 and the expressions of alpha-SMA and E-Cadherin were observed by Western blot. The contents of TGF-B1, fibronectin and type I collagen in the supernatants of the cultured HKC were detected by enzyme-linked immunosorbent assay (ELISA). The expression of TGF-beta1 mRNA was measured by reverse transcription and polymerase chain reaction (RT-PCR). RESULTS: Compared with LG group, the expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta1, mRNA were significantly increased in HG group from 6 to 72 hours. Meanwhile, the contents of TGF-beta1 and collagen I in the supernatants and the expression of alpha-SMA increased and the expression of E-Cadherin decreased. The expressions of JAK2, p-STAT1, p-STAT3, and TGF-beta mRNA as well as the levels of TGF-beta1 and collagen I in the supernatant s in HG + AG490 group were significantly lower than in the HG group. The expressions of alpha-SMA and E-Cadherin were also decreased in HG + AG490 group. CONCLUSION: Activation of JAK/STAT signaling pathway may be involved in the high glucose-induced transdifferentiation and overproduction of TGF-beta1, and ECM proteins in HKCs.

[Sensory gating of patients with first-episode schizophrenia].

OBJECTIVE: To investigate the characteristics of sensory gating P50 of patients with first-episode schizophrenia. METHODS: The auditory evoked potentials P50 were recorded in 66 patients (Group Sch) with first-episode schizophrenia and 92 normal controls (Group NC) by using conditioning/testing paradigm presented with auditory double click stimuli. RESULTS: The value of S1-P50 of Group Sch was 3 microV +/- 2 microV, significantly lower than that of Group NC (6 microV +/- 3 microV, P <0.01). The value of S2-P50 of Group Sch was 4 microV +/- 2 microV, significantly higher than that of Group NC (2 microV +/- 1 microV, P < 0.01). The S2/S1 ratio of Group Sc was 81% +/- 40%, significantly higher than that of Group NC (42% +/- 21%, P < 0.01). The value of S2 - S1 of Group Sch was 2 microV +/- 1 mciroV, significantly lower than that of Group Sch (3 mciroV +/- 2 microV). The value of 100 (1-S2/S1) of Group Sch was 19% +/- 17%, significantly lower than that of Group NC (58% +/- 21% , P < 0.01). CONCLUSION: Sensory gating deficit exists in the patients with first-episode schizophrenia, manifested in deficiency of inhibition that can be quantitatively observed by measuring auditory evoked potential P50.

[Protective effects of Lovastatin on early diabetic renal tissue and the possible mechanism].

OBJECTIVE: To investigate the protective effects of Lovastatin on renal function in experimental diabetic nephropathy in rats. and the function of cAMP-responsive element binding protein (CREB1) in this duration. METHODS: Diabetes was induced in male Wistar rats by intrapetitoneal injection of STZ (65 mg/kg). Three groups were divided as: Sham group, diabetic control group and Lovastatin treatment group. Lovastatin (20 mg/kg) was administered daily by gavage from the next day of the induction diabetes for 4 weeks. Upro, ucr in urine and Glu, Scr, BUN in serum were determined. Immunohistochemistry and computer image-pattern analysis system were used to analyze expression of PCNA and p-CREB1. Western blot were performed to valuate the expression of p-CREB1 with their specific corresponding antibodies. CREB1 mRNA was measured by RT-PCR. RESULTS: After Lovastatin treatment, renal function were ameliorative in diabetic rats. Decrements were also found in the expression of and PCNA, p-CREB1 and its mRNA in the treatment group compared with the diabetic group. CONCLUSION: Inhibition of glomerular cAMP-responsive element binding protein 1 may be responsible for the Lovastatin protective function that allevate the renal proliferation and hypertrophy in diabetic rats.

[Effect of losartan on expression of Janus kinase 2 and signal transducer and activator of transcription 3 in glomeruli of diabetic rats].

OBJECTIVE: To investigate the effects of losartan on Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 in glomeruli of diabetic rats. METHODS: Sixty Wistar male rats were randomly divided into control group (n=20), diabetes group (n=20), and losartan treatment group (n=20). Diabetes was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg/kg). Losartan (10 mg/kg) was administered daily by gavage from the day following the induction of diabetes. The animals were sacrificed in the weeks 2 and 4 after STZ injection. The renal cortical tissues were obtained and glomeruli were isolated. The protein expressions of JAK2, STAT3 and tyrosine phosphorylated STAT3 (p-STAT3) were assessed respectively by Western blot. Immunoprecipitation and Western blot analysis were used to determine tyrosine phosphorylated JAK2 (p-JAK2). JAK2 and STAT3 mRNA were assayed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Compared with the control group rats, the respective expression of JAK2, p-JAK2, STAT3, p-STAT3, JAK2 mRNA and STAT3 mRNA was significantly increased in the diabetic glomeruli without losartan treatment (all P<0.01). After treatment with losartan, the expression of p-JAK2 and p-STAT3 in the diabetic glomeruli was down-regulated (all P<0.05). However losartan had no effect on the expression of JAK2, STAT3, JAK2 mRNA and STAT3 mRNA in the diabetic glomeruli. CONCLUSION: JAK2 and STAT3 signal proteins may be involved in the kidney damage associated with diabetes. Regulation of phosphorylation of JAK2 and STAT3 may be responsible for the renal protective effects of losartan in diabetic rats.

[Tubular epithelial-myofibroblast transdifferentiation and expressions of hepatocyte growth factor and Smad7 in renal tissues of rat with experimental diabetes].

OBJECTIVE: To investigate the relationship of tubular epithelial-myofibroblast transdifferentiation and the expressions of hepatocyte growth factor (HGF) and Smad7, and to elucidate the role of HGF and Smad7 in diabetic nephropathy. METHODS: Diabetes was induced in male Wistar rats with right nephrectomy and streptozotocin (STZ) administration. The expressions of cytokeratin 18 (CK18), alpha-smooth muscle actin (alpha-SMA), HGF and Smad7 were assayed with immunohistochemistry. The expressions of alpha-SMA, HGF were assayed with flow cytometry. The expression of Smad7 was assessed by Western blot. RESULTS: Compared with those in kidneys of the control group, diabetic kidneys showed down-regulated expression of CK18 and up-regulated expression of alpha-SMA. The expressions of HGF and Smad7 were increased significantly in the kidneys of diabetic rats at first, then they decreased gradually, but were still higher than those of control. CONCLUSION: The tubular epithelial cells may undergo phenotypic alterations and change to myofibroblasts. The absence of up-regulation of HGF and Smad7 may be related with the transdifferentiation of tubular cells in this animal model.

[Effects of benazepril on apoptosis in the kidney of diabetic rats].

AIM: To investigate the effects of angiotensin converting enzyme inhibitor (ACEI) on apoptosis and the expression of Fas and Fas-L in the kidney of diabetic rats. METHODS: Uninephrectomized Spraque-Dawley rats were used to induce diabetes by intraperitoneal injection of streptozotocin (65 mg.kg-1). Benazepril (10 mg.kg-1) was given daily by gavage from the next day of the induction to diabetes for 12 weeks. Apoptosis was evaluated by means of terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling (TUNEL). Flow cytometry and immunohistochemistry were used to detect the expression of Fas and Fas-L. RESULTS: Compared with those in the kidneys of control group, apoptotic cells were more in number and the expression of Fas and Fas-L was higher in the diabetic kidneys (P < 0.05). The number of apoptotic cells and the level of expression of Fas and Fas-L were reduced by benazepril treatment (P < 0.05). CONCLUSION: Angiotensin converting enzyme inhibitor benazepril showed some renal protective effect on diabetic nephropathy, partly through inhibiting apoptosis by down-regulating Fas and Fas-L expression.

[Effects of puerarin on renal function, expressions of MMP-2 and TIMP-2 in diabetic rats].

AIM: To investigate the effect of puerarin on expressions of MMP-2 and TIMP-2 in the kidney of diabetic rats. METHODS: Uninephrectomized male Wistar rats were used to induce diabetes by intraperitoneal injection of streptozocin (65 mg x kg(-1)). Puerarin was given daily by intraperitoneal injection from the third day of induction of diabetes for 16 weeks. Using in situ hybridization and immunohistochemistry to detect MMP-2, TIMP-2 mRNA expressions and MMP-2, TIMP-2, collagen IV and Laminin expressions in diabetic kidneys with image analysis system, Flow cytometry was used to detect the expressions of TGFbeta1, MMP-2 and TIMP-2. RESULTS: Compared with those in kidneys of control group, expressions of MMP-2 mRNA and proteins were lower, while the expressions of both TGFbeta1 and TIMP-2 were higher in the diabetic kidney (P < 0.05). The level of MMP-2 expression was advanced, while expression of TIMP-2 was reduced by puerarin treatment (P < 0.05). CONCLUSION: Puerarin showed some renal protective effect on diabetic nephropathy, partly through inhibition of excessive deposition of glomeruli extracellular matrix by up-regulating MMP-2 and down-regulating TIMP-2 expressions besides reducing the blood glucose.

[Effects of lovastatin on renal function and expression of phosphorylating-p38 mitogen-activated protein kinase in experimental diabetic nephropathy in rats].

OBJECTIVE: To investigate the effects of lovastatin on renal function, activity and expression of the p38 mitogen-activated protein kinase (MAPK) and cAMP responsive element-binding protein (CREB) in experimental diabetic nephropathy in rats. METHODS: Eighteen uninephrectomized male Wistar rats were randomly divided into three groups: control (n=6), diabetic (n=6) and lovastatin treatment group (n=6). Diabetes was induced by intraperitoneal injection of STZ (65 mg/kg). Lovastatin (20 mg/kg) was administered daily by gavage from the next day of the induction diabetes for 4 weeks. Four weeks later, animals were sacrificed and samples were collected to determine various parameters, including protein and creatinine in urine (Upro and UCr), and glucose (Glu), creatinine (SCr), blood urea nitrogen (BUN) in serum. Immunohistochemistry and computer image-pattern analysis system were used to analyze activation of P-p38 MAPK and P-CREB, the expression of transferase growth factor-beta(1) (TGF-beta(1)), fibronectin (FN), laminin (LN) in renal glomeruli were also measured. RESULTS: Expression of P-p38 MAPK and P-CREB in diabetic glomeruli in diabetic rats were higher than the controls, the same as the expression of TNF-beta(1), FN, LN(all P<0.01). After lovastatin treatment, expression of P-p38 MAPK, P-CREB and TGF-beta(1), FN, LN were markedly decreased compared with diabetic group(all P<0.01). CONCLUSION: Inhibition of glomerular p38 MAPK signal transduction pathway may be responsible for the decrement of extracellular matrix accumulation and renal protective effects of lovastatin in uninephrectomized rats.

[The relationship between endoplasmic reticulum stress and its particular apoptosis way caspase-12 and apoptosis in renal cortex of diabetic rats].

OBJECTIVE: To investigate the expressions of 78-kDa glucose-regulated protein (GRP78) and Caspase-12 and their relationship with apoptosis in renal cortex of diabetic rats. METHODS: Uninephrectomized Wistar rats were used to induce diabetes by intraperitoneal injection of Streptozotocin (STZ 65 mg/kg). After 8 weeks, the expression and distribution of GRP78, Caspase-12, proliferating cell nuclear antigen (PCNA) were examined by immunohistochemistry. Flow cytometry was used to detect the levels of protein of GRP78 and Caspase-12. Apoptosis was evaluated by means of terminal deoxynucleotidyl transferase-mediated d-UDP nick-end labeling (TUNEL) and Flow cytometry. Serum creatinine, blood urea nitrogen and 24-hour urine protein excretion were checked. RESULTS: Compared with those in normal control group, the numbers of apoptosis and the expression of GRP78, Caspase-12 in glomerular and tubular cells were much higher in the diabetic kidneys at 8 weeks. There was no significant difference between group A and group B. CONCLUSION: Activation of endoplasmic reticulum stress may play an important role in the development of diabetic nephropathy.