Expression of fractalkine and CX3CR1 in renal tissues of patients with WHO class IV lupus nephritis

AIM: To observe the expression of fractalkine, and its receptor, CX3CR1, in renal tissues of patients with diffuse proliferative lupus glomerulonephritis (WHO class IV), minimal glomerular abnormalities, and normal kidney. Meanwhile, the correlation among the expression of fractalkine, CX3CR1 and CD68-positive macrophages was investigated, and the role of fractalkine and CX3CR1 in the pathogenesis of lupus nephritis was discussed. METHODS: The expressions of fractalkine, CX3CR1 and CD68 were detected immunohistochemically in kidney tissue sections obtained from twenty-one patients with WHO class IV lupus nephritis, eighteen cases with minimal glomerular abnormalities, and eight normal kidneys which were no abnormality under light microscope. RESULTS: (1) Fractalkine was generally indistinguishable in tissue sections from normal kidney and minimal glomerular abnormalities. CX3CR1-positive cells and CD68-positive macrophages were sparsely detected in the glomeruli and in the cortical interstitium. (2) There were considerable CX3CR1-positive cells and macrophages in both the glomeruli and the interstitium in sections from class IV lupus nephritis. The number of CX3CR1-positive cells significantly correlated with the number of macrophages in the glomeruli and in the interstitium respectively (r=0.956, P<0.01 and r=0.965, P<0.01). (3) Significant expression of fractalkine was seen in the cortical renal tubules from class IV lupus nephritis. The percentage of fractalkine-positive tubules significantly correlated with the number of CX3CR1-positive cells and macrophages in the interstitium respectively (r=0.720, P<0.01 and r=0.770, P<0.01). CONCLUSION: These expression patterns show that fractalkine and CX3CR1 may play an important role in the pathogenesis of class IV lupus nephritis.     

Up-regulation of CD36 induced by casein-induced inflammation promotes renal injury in mice

AIM: To investigate the role of CD36 in casein-induced mouse renal injury.METHODS: Eight-week-old male C57BL/6J mice and CD36 knockout (CD36KO) mice were randomly divided into C57BL/6J saline injection group, C57BL/6J casein injection group and CD36KO casein injection group (n=8 in each group). After 14 weeks of treatment with high-fat diet, the mouse serum, 24 h urine and kidney tissue samples were collected for analysis. The serum content of tumor necrosis factor-α (TNF-α) was measured by ELISA. The renal function markers in the serum and urine were determined by an automatic biochemical analyzer. The pathological changes of the kidney were observed by HE staining and Masson staining. The expression of CD36 and cytokines/chemokines (TNF-α, IL-6 and MCP-1) at mRNA and protein levels in the renal tissues were determined by real-time PCR and Western blot. The content of tissue hydrogen peroxide (H₂O₂) was measured by a commercial kit. The protein levels of Nrf2 and TGF-β1 in the renal tissues were measured by immunohistochemical staining.RESULTS: Compared with saline injection group, casein injection increased the level of TNF-α in the serum and in the kidney tissues of C57BL/6J mice (P<0.05), suggesting that casein injection successfully induced chronic inflammation in C57BL/6J mice. Casein injection also promoted the protein expression of CD36 and TGF-β1 in the renal tissues of the C57BL/6J mice, accompanied with glomerular sclerosis, proteinuria, increased serum creatinine content, increased H₂O₂ content, and decreased Nrf2 protein level and the ability of antioxidant in the kidneys (P<0.05). Furthermore, CD36 deficiency protected the mice from casein-induced renal injury, as evidenced by improved kidney pathological changes and decreased proteinuria. The content of H₂O₂ in the kidneys of casein-treated CD36 knockout mice was also lower than that in casein-treated C57BL/6J mice.CONCLUSION: Inflammatory responses promote the oxidative stress and renal injury in a CD36-dependent manner.     

Effect of lupus recipe on immune system and lymphocyte subsets proliferation in splenic cells of lupus-prone BXSB mice

AIM: To investigate the effects of lupus recipe on immune system and lymphocyte subsets proliferation in splenic cells in BXSB mice. METHODS: Eighteen male BXSB mice model was used in the experiment. The model mice were divided into three groups: un-treated model group, lupus recipe (LR) treated group, and prednisone treated group. All model mice were killed in 10 weeks. The control group consisted of 6 syngeneic normal C57BL/6 male mice. The levels of total IgG and anti-dsDNA antibody in serum were detected by ELISA. The percentages of lymphocyte subsets (CD3+, CD4+, CD8+ T lymphocytes and CD19+, CD23+ B lymphocytes) were detected by using flow cytometry analysis. RESULTS: (1) The serum levels of total IgG and anti-dsDNA antibody in un-treated model group were higher than that in other groups. There was no differences among LR treated group, prednisone treated group and control group. (2) The percentages of CD3+, CD4+, CD8+ T lymphocytes and CD19+, CD23+ B lymphocytes in model group were obviously higher than that in normal control. (3) Compared to un-treated model group, the percentages of CD4+, CD8+ T lymphocytes and CD19+, CD23+ B lymphocytes in LR or prednisone treated group were significantly reduced, which closely reached the levels in normal group. CONCLUSIONS: The immune functions of T and B lymphocytes in BXSB mice are up-regulated. LR inhibits the activation of T and B lymphocytes, reduces the serum levels of IgG and auto-antibody production.     

Effects of arsenic trioxide on T-bet/GATA3 signal pathway in MRL/lpr mice

AIM: To investigate the effect of arsenic trioxide (ATO) on T-bet/GATA3 signal pathway in MRL/lpr mice.METHODS: MRL/lpr mice and C57BL/6J mice at the age of 20 weeks were chosen and then divided in 2 different sub-groups, respectively. The mice in 2 sub-groups received ATO (0.4 mg·kg^-1·d^-1) and sodium chloride (NS, volume weight-determined) by intraperitoneal injection respectively for 2 months. Afterward, the spleens were isolated from the MRL/lpr and C57BL/6J mice under pathogen-free condition and the suspensions were prepared. The mRNA level of T-bet, GATA3, IFN-γ,IL-4 and the mRNA ratio of T-bet/GATA3 were detected by RT-qPCR. The protein expression of T-bet and GATA3 was determined by Western blot. The serum levels of IFN-γ and IL-4 were measured by ELISA.RESULTS: The mRNA and protein levels of T-bet, IFN-γ and the mRNA ratio of T-bet/GATA3 in NS group of MRL/lpr mice were higher than those in NS group of C57BL/6J mice (P<0.05). However, the GATA3 and IL-4 were lower in NS group of MRL/lpr mice in both mRNA and protein level (P<0.05). In MRL/lpr mice, the mRNA and protein levels of T-bet, IFN-γ and the mRNA ratio of T-bet/GATA3 were lower in ATO group compared with NS group (P<0.05), no difference was found in GATA3 and IL-4. No difference of the indexes mentioned above between ATO group and NS group in C57BL/6J mice was observed.CONCLUSION: ATO may affect the signaling pathway of T-bet/GATA3 to down-regulate the mRNA expression and the protein secretion of IFN-γ by decreasing the expression of T-bet in MRL/lpr mice.     

Molecular mechanism of BMSC intracerebral transplantation in improving learning and memory abilities of AD mice

AIM: To investigate the effect of bone marrow mesenchymal stem cell (BMSC) transplantation on learning and memory abilities and pathological changes of Alzheimer disease (AD) mice and the molecular mechanisms. METHODS: C57/BL6 wild-type (WT) and transgenic (Tg) mice were randomly divided into 4 groups:WT/PBS group, WT/BMSCs group, Tg/PBS group and Tg/BMSCs group. The mice were administered with PBS or BMSCs via intracerebroventricular injection. Spatial learning and memory abilities of the mice were evaluated by Morris water maze test on the 3rd day after surgery. Real-time PCR was applied to detect the mRNA expression of CX3C chemokine ligand 1 (CX3CL1), CX3C chemokine receptor 1 (CX3CR1), IL-1β, TNF-α, Nurr1, YM1, insulin-degrading enzyme (IDE) and matrix metalloproteinase 9 (MMP9). The protein levels of CX3CL1 and Aβ42 were measured by ELISA. Western blot was used to detect the protein expression of postsynaptic density protein 95 (PSD95) and synaptophysin (SYP). RESULTS: The transplanted BMSCs were observed near the hippocampus of APP/PS1 mice on the 10th postoperative day. The escape latency of the mice in Tg/PBS group was significantly longer than that in the WT/PBS mice (P<0.05). Compared with Tg/PBS group, the escape latency of Tg/BMSCs group was significantly shorter (P<0.05), and the mRNA and protein levels of CX3CL1 in Tg/BMSCs group were significantly higher than those in Tg/PBS group (P<0.01). The results of immunohistofluorescence staining showed that BMSC transplantation promoted the activation of microglia in the brain of WT and Tg mice. The mRNA expression of YM1 was up-regulated in WT/BMSCs group and Tg/BMSCs group (P<0.05). Compared with WT/PBS mice, the mRNA expression of TNF-α in the cortex and hippocampus of Tg/PBS group was significantly increased (P<0.05), and the mRNA expression of Nurr1 in the cortex was significantly decreased (P<0.01). Meanwhile, the mRNA expression of TNF-α in the cortex of Tg/BMSCs mice was decreased (P<0.01) and the mRNA expression of CX3CR1 and Nurr1 was up-regulated compared with Tg/PBS group (P<0.05). The results of Western blot showed that the protein levels of PSD95, p85, p110 and p-Akt in Tg/BMSCs group were significantly higher than those in Tg/PBS group (P<0.05). Finally, BMSC transplantation reduced the protein level of Aβ42 in APP/PS1 mice (P<0.05), and increased the mRNA expression of IDE and MMP9 in the hippocampus (P<0.05). CONCLUSION: BMSC transplantation modulates neuroinflammatory responses and promotes neuroprotective factor and synaptic protein expression, thus improving the learning and memory abilities in the APP/PS1 mice, which may be achieved by up-regulating the expression of CX3CL1.     

Development and study of experimental C57BL/6 mouse lupus nephritis model induced by pristane

AIM To establish a C57BL/6 mouse lupus nephritis model induced by pristane and to explore the pathogenic mechanism of this model. METHODS Thirty C57BL/6 mice were randomly divided into 2 groups. The mice in model group were intraperitoneally injected with 0.5 mL pristane, while the mice in control group were injected with 0.5 mL normal saline. The state of health and survival of the animals were monitored during the whole experiment. The activation of macrophages, granulocytes, dendritic cells and B cells in spleen and the markers on B cells were detected by flow cytometry on the 10th day after injection. The serum levels of antinuclear antibodies (ANA) and anti-double strand DNA antibodies (anti-dsDNA) were measured every month after injection by indirect immunofluorescence assay, and proteinuria was checked mouthy by Albustix test strips. Eight months after injection, all mice were killed, and the kidneys were slided and stained with HE or PE-labeled IgG to analyze the expression of interferon-γ (IFN-γ) and interleukin-4 (IL-4). The evidence of glomerulonephritis was histopathologically observed, and the ultrastructural changes of the glomerulus were determined by transmission electron microscopy. RESULTS Ten days after the pristane injection, the populations of macrophages, granulocytes, dendritic cells and B cells were increased significantly compared with control mice (P<0.05). The expression of B7-1, B7-2 and MHC-II on the B cells was also increased (P<0.05). The serum levels of ANA and anti-dsDNA were increased from 3 to 8 months (P<0.05). Meanwhile, part of the mice showed different degrees of ascites, emaciation or even death, part of the mice had proteinuria 4 months later, and 8 months later, all of the model mice had proteinuria, with 1~20 g/L of urine protein. At the 8th month, a large number of heterotopic lymphoid tissues appeared in the abdominal cavity. The deposition of immune complexes in glomeruli and mesangial areas was serious. The expression of IFN-γ in the renal tissues was increased. Pathological damages such as lymphocyte infiltration, tissue necrosis and deposition of electron dense substances were obvious in the model mice. In control group, autoantibodies and proteinuria was not detected under the same experimental condition. Meanwhile, no evidence of glomerulonephritis in the control mice was observed. CONCLUSION The C57BL/6 mouse model of lupus nephritis induced by pristane is established successfully.     

Strain difference of susceptibility to caerulein-induced acute pancreatitis in mice

AIM: To study the difference of susceptibility to caerulein-induced acute pancreatitis (AP) among the mice of C57BL/6J, BALB/c and ICR strains.METHODS: Two-month-old female mice of C57BL/6J, BALB/c and ICR strains (12 mice for each strain) were divided into control group (n=6) and experimental group (n=6), respectively. The mice were intraperitoneally injected with caerulein (50 μg/ kg) in 1 h interval for 7 serial injections in total. The mice in control group were treated with saline according to the same procedure in experimental group. The blood samples were collected at 0 h, 3 h, 6 h, 9 h, 12 h and 24 h after the first injection of caerulein or saline for plasma α-amylase and lipase assays. The mice were sacrificed 24 h after AP induction, and the pancreatic tissues were harvested for further investigating the pathological changes and expression of inflammatory factors.RESULTS: After AP induction, the mice of BALB/c and ICR strains demonstrated more dramatic increase in plasma α-amylase activity and lipase activity than those of C57BL/6J mice. C57BL/6J mice showed milder morphological changes and lower expression of inflammatory factors in pancreata than those of BALB/c and ICR mice.CONCLUSION: The mice of C57BL/6J strain have less susceptibility to caerulein-induced AP than that of BALB/c and ICR mice.     

Protective effect of curcumin on MRL/lpr mice with lupus nephritis and its mechanism

AIM To observe the effect of curcumin （Cur） on lupus nephritis （LN） and its possible mechanism. METHODS Thirty 10-week-old MRL/lpr lupus mice were randomly divided into MRL/lpr group， Cur-L and Cur-H group with 10 mice in each group， and C57BL/6 mice （n=10） served as normal control （NC） group. The mice in Cur-L group and Cur-H group were given intragastric administration of Cur at 100 and 200 mg·kg^-1·d^-1 for 12 weeks， respectively， and the same volume of normal saline was given to the mice in NC group and MRL/lpr group. The urine protein was detected， and the morphological changes of the renal tissue were observed by HE staining after treatment. The levels of serum creatinine （SCr）， blood urea nitrogen （BUN） and serum anti-double-stranded DNA （dsDNA）， and interleukin-1β （IL-1β）， IL-6 and tumor necrosis factor-α （TNF-α） levels in serum and renal tissues were detected. The protein levels of p-IκB， NF-κB， NLRP3 and caspase-1 in the renal tissues were determined by Western blot. RESULTS Compared with MRL/lpr group， the content of urine protein in Cur groups was significantly reduced， and the renal injury was relieved. The SCr， BUN， serum anti-dsDNA， and the serum and renal levels of IL-1， IL-6 and TNF-α were all significantly reduced， and the protein levels of p-IκB， NF-κB， NLRP and caspase-1 in the renal tissue were significantly decreased （P<0.05）. CONCLUSION Cur has a certain protective effect on the kidney of MRL/lpr mice， and its mechanism may be related to the inhibition of NF-κB and NLRP3 signaling pathways.     

Role of Api6 in lung inflammation induced by high fat/cholesterol food in C57BL/6J mice

AIM：To investigate the function of apoptosis inhibitor 6 (Api6) in lung inflammation induced by high-fat high-cholesterol diet (HFD/HCD) in male C57BL/6J mice. METHODS：Male C57BL/6J mice (6~8 weeks old) were randomly divided into 2 groups and treated with regular diet and HFD/HCD, respectively. After 16 weeks of feeding, the lung tissues were collected and the pulmonary inflammatory status was determined by immunohistochemistry and ELISA. The mRNA and protein expression levels of Api6 were determined by real-time PCR and Western blotting. The apoptotic rate of bronchioalveolar lavage cells was examined by flow cytometry. RAW264.7 cells were cultured in vitro and the apoptosis induced by oxidized low-density lipoprotein (oxLDL) was detected by flow cytometry. RESULTS：Accumulation of macrophages and increases in both tumor necrosis factor α and monocyte chemoattractant protein 1 were observed in the lung tissues of 16-week HFD/HCD-fed C57BL/6J mice. Compared with the regular diet-fed mice, the expression of Api6 at mRNA and protein levels in the lung tissues was highly increased in the HFD/HCD-fed mice (P<0.01). Meanwhile, the apoptotic rate of bronchioalveolar lavage macrophages from the HFD/HCD-fed mice was highly inhibited (P<0.01). In vitro, 500 μg/L recombinant Api6 significantly inhibited the apoptosis of RAW264.7 cells induced by oxLDL (P<0.05). CONCLUSION：HFD/HCD feeding results in the accumulation of macrophages in the lung of C57BL/6J mice, which may partly due to the increased expression of Api6 and its anti-apoptotic role in macrophages.     

L-4F attenuates the injury of lupus nephritis in a lupus mouse model

AIM: To investigate the effects of apolipoprotein A-I mimetic peptide L-4F on the process of nephropathia in apoE-/-Fas-/-C57BL/6 lupus mice. METHODS: The apoE-/-Fas-/-C57BL/6 lupus mice (8~9 weeks old, female) were treated with L-4F by peritoneal injection for 25 weeks. RESULTS: Compared with the vehicle controls, the mice treated with L-4F presented smaller lymph nodes and glomerular tufts (P<0.05), lower serum levels of IgG antibodies to double-stranded DNA (P<0.05) and oxidized phospholipids, as well as lower levels of inflammatory factors including IL-6 and TNF-α (P<0.05). Furthermore, serum adiponectin level in apoE-/-Fas-/-C57BL/6 mice was significantly increased after L-4F treatment for 25 weeks. CONCLUSION: L-4F treatment significantly attenuates the development of lupus nephritis in apoE-/-Fas-/-C57BL/6 lupus mice, indicating a potential clinical value of L-4F in the treatment of lupus nephritis.     

The therapeutic effect of embryonic stem cells on acute lung injury induced by bleomycin in mice

AIM: The aim of this study was to observe and compare the therapy effect of different kinds of embryonic stem cells (ESCs) on pulmonary injury of mice exposed to bleomycin. These embryonic stem cells were C57BL/6J-ESC,S8-ESC and human-ESC.METHODS: (1) Fifty C57BL/6J female mice were divided randomly into five groups, which were blank control group, bleomycin model group, bleomycin model injected with C57BL/6J-ESC group, bleomycin model with S8-ESC group and bleomycin model with human ESC group. Every group has ten mice. (2) The mice of control group were administrated 0.9% sodium chloride solution and the mice in other four groups were administrated bleomycin intratracheally. Three different kinds of ESCs were administrated to the mice in three different ESCs-treated groups respectively one hour after bleomycin exposure. The life-span and hydrocyproline concentration were examined. The pathologic changes of the lung and the engraftment of the ESCs in the injured lung were observed. RESULTS: (1) The death rate in three different ESCs-treated groups declined much more obviously than that in the control group on 8 days after bleomycin exposure (bleomycin model group 50%, C57BL/6J-ESC group 37.5%, S8-ESC group 20%, human-ESC group 20%). (2) The extent of pathologic changes of the lung in S8-ESC group was lighter significantly than that in the bleomycin model group, but in C57BL/6J-ESC group and human-ESC group, their pathologic changes were similar to that in bleomycin model group. (3) The hydrocyproline concentration in S8-ESC group was lower distinctly than that in bleomycin model group (P<0.01); the hydrocyproline concentration in human-ESC group was also lower than that in bleomycin model group (P<0.05); there was no significant difference between C57BL/6J-ESC group and bleomycin model group (P>0.05). (4) The positive signals of three kinds of ESCs could be found in the lung at 1, 3, 12 and 24 hours after the stem cells were administrated, but signals were the strongest 3 hours after stem cells were given. All of the signals disappeared three days later. CONCLUSION: S8-ESCs transplantation can improve the tolerence of mice to bleomycin and ameliorate acute lung injury.     

“2012年园艺植物染色体倍性操作与遗传改良学术研讨会”预备通知

自2008年11月在中国农业科学院郑州果树研究所成功召开园艺植物染色体倍性操作与遗传改良研讨会以来,我国科研人员在该领域的研究取得了可喜的成绩。为进一步总结近几年来在该领域的研究进展,促进园艺植物倍性育种研究,同时为该领域的专家、学者和同仁们提供良好的交流平台。中国园艺学会定于2012年4月中旬在重庆召开园艺植物染色体倍性操作与遗传改良学术研讨会。欢迎从事该研究领域及相关研究工作的人员参加。     

Effects of ketamine on α-synuclein and astrocyte in mice with Parkinson disease induced by MPTP

AIM To investigate the effects of ketamine at subanesthetic dose on α-synuclein and astrocyte in mice with Parkinson disease (PD) induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). METHODS Thirty-six healthy male C57BL/6 mice were randomly divided into 3 groups (12 mice per group): NaCl group (intraperitoneal injection of saline), MPTP group (intraperitoneal injection of MPTP) and ketamine group (intraperitoneal injection of MPTP and ketamine). The behavioral differences among the mice in the 3 groups were examined by tail suspension test and gait analysis test. Immunofluorescence staining and Western blot were used to detect the expression of α-synuclein and glial fibrillary acidic protein (GFAP) in the substantia nigra (SN), caudate putamen (CP) and visual cortex (CX). RESULTS According to the results of tail suspension test and gait analysis test, the mice in MPTP group showed increased duration of immobility and shortened step length compared with NaCl group, while those in ketamine group showed decreased duration of immobility and expanded step length compared with MPTP group (P<0.05). According to the results of immunofluorescence staining and Western blot, the mice in MPTP group showed significantly increased expression of α-synuclein and GFAP in SN, CP and CX compared with NaCl group, while those in ketamine group showed significantly decreased expression of a-synuclein and GFAP in SN, CP and CX compared with MPTP group (P<0.05). CONCLUSION Ketamine at subanesthetic dose inhibits the expression of α-synuclein and the proliferation of astrocytes in MPTP-induced PD mice.     

Effect of L-glutamine on obesity and insulin resistance in high-fat diet-induced C57BL/6J mice

AIM:To explore the effect of L-glutamine (Gln) on obesity and insulin resistance in high-fat diet(HFD)-induced C57BL/6J mice. METHODS:Male C57BL/6J mice (n=60) were randomly divided into normal control (NC) group, HFD group, HFD+L-alanine (Ala) group and HFD+Gln group. Each group had 15 mice. The body weight of the mice was recorded weekly. Fasting blood glucose (FBG) of the mice was tested after 12-h fasting only with water-drinking at the end of the 16th week. The mice were sacrificed and epididymal fat pad was measured. The levels of insulin (INS), leptin (LEP), adiponectin (APN) and glucagon-like peptide-1 (GLP-1) were measured by ELISA. The insulin resistance index (IRI) and insulin sensitivity index (ISI) were calculated. RESULTS:Compared with NC group, the body weight, epididymal fat pad weight, and the levels of FBG, INS, IRI and LEP increased significantly in HFD group (P<0.05), while the levels of ISI and APN decreased significantly (P<0.05). Compared with HFD group, the body weight, and the levels of FBG, IRI and LEP decreased significantly in HFD+Gln group (P<0.05), while the levels of ISI and APN increased significantly (P<0.05). No significant difference of serum GLP-1 levels the four groups was observed. CONCLUSION:L-glutamine reduces the body weight and attenuates the insulin resistance of HFD-induced mice.     

Effect of puerarin injection on epithelial-mesenchymal transition in renal tubular epithelial cells of diabetic KKAy mice

AIM:To observe the effect of puerarin injection on the expression of epithelial-mesenchymal transition-related proteins in KKAy mice with renal interstitial fibrosis (RIF). METHODS:Sixteen KKAy mice were randomly divided into model group (n=8) and puerarin injection treatment group (n=8), and 8 C57BL/6J mice were used as normal controls. The mice in treatment group were intraperitoneally given puerarin injection from the 14th week. The blood glucose levels were observed on a daily basis. The mice were sacrificed at the 24th week.The renal pathological changes were observed under light microscope. The expression of α-smooth muscle actin (α-SMA), transforming growth factor β1 (TGF-β1) and transforming growth factor β type I receptor (TGF-β-RI) in the renal tissues were examined by immunohistochemical staining. RESULTS:Fibrosis was found in the KKAy mice of model group, while the mice in treatment group showed a slight increase in renal interstitium. Treatment with puerarin injection decreased the protein expression levels of α-SMA, TGF-β1 and TGF-β-RI in the kidney tissues as compared with those in model group. CONCLUSION: Puerarin injection reduces the expression of α-SMA, and restrains the protein expression of TGF-β1 and TGF-β-RI in the kidney tissue of KKAy mice. These changes may inhibit and reverse the process of epithelial-mesenchymal transition, thus delaying the occurrence and development of RIF.     

Panaxadiol saponins and dexamethasone have similar actions on LPS-induced AKI in mice

AIM：To investigate whether the panaxadiol saponins (PDS) and dexamethasone (DEX) have similar effects on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). METHODS：C57BL/6 mice were randomly divided into 4 groups: the control mice received intraperitoneal injection of normal saline; in LPS group, the mice were subjected to intraperitoneal injection of LPS (10 mg/kg); in PDS + LPS group and DEX + LPS group, the mice were injected intraperitoneally with PDS (25.0 mg/kg) and DEX(2.5 mg/kg) 1 h before LPS injection, respectively. The blood was collected from the hearts, and the kidneys were collected for the biochemical and Western blotting analysis 12 h after LPS injection. RESULTS：LPS induced AKI, evidenced by markedly increased blood urea nitrogen (BUN) and creatinine (CREA) contents compared with control group (P<0.01). However, serum contents of CREA and BUN obviously reduced in PDS + LPS group and DEX + LPS groups compared with LPS group (P<0.05). Both PDS and DEX decreased the production of TNF-α and IL-6 by inhibiting renal NF-κB signaling activation. PDS and DEX also down-regulated the expression of inducible nitric oxide synthase, up-regulated the expression of manganese superoxide dismutase and reduced oxidative stress in the kidneys of LPS-challenged mice. In addition, treatment with PDS and DEX significantly increased the nuclear glucocorticoid receptor in the kidneys of LPS-treated mice. CONCLUSION：PDS and DEX have inhibitory effects on LPS-induced AKI mice. However, it is unclear whether PDS reduces LPS-induced AKI via direct action on glucocorticoid receptor.     

Expression of scavenger receptor B1 (SR-B1) in the liver of high fat and sugar diet-induced diabetic mice

AIM: To investigate serum lipid and the expression of SR-B1 in the livers of diabetic mice. METHODS: Ten normal diet, female C57BL/6J mice, fifteen high fat and sugar diet female C57BL/6J mice, five fed 8 weeks and ten fed 16 weeks were used in the experiment. Serum total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), insulin (INS) and the expression of SR-B1 in the livers were measured. RESULTS: 1. In the high fat and sugar diet mice, serum TC and FBG at 16 weeks were significantly higher than that in normal diet mice (P<0.05). 2. The expression of SR-B1 protein in the liver of high fat and sugar diet mice was the higher than that in normal mice, and the SR-B1 expression in the liver of the mouse fed 16 weeks was also higher than that fed 8 weeks. CONCLUSION: The expression of SR-B1 protein in the liver of type 2 diabetes mice is higher than that in normal mice, perhaps it is related to the decrease in serum HDL-C.     

PPARγ gene and protein expression in aortic plaque of different week-old apoE-knock out mice and the relationship with the composition of aortic plaque

AIM: To investigate the relationship of PPARγ gene expression with the composition of aortic plaque in apoE-knock out mice. METHODS: PPARγ gene and protein in aortic area of 20-week-old and 40-week-old apoE-knock out mice were investigated using RT-PCR and immunoblotting. The same aged wild type mice (C57BL/6J) were served as control (n=10). The composition of aortic plaques was analyzed by Movat method and oil red O staining. The expression of antigens such as PPARγ, SM-actin and MOMA-2 in aortic plaque were compared using immunohistochemistry. The relationship of PPARγ with macrophage, smooth muscle cells (SMC), lipid, elastic fiber, collagen and proteoglycan in aortic plaque were analyzed using immunofluorescence. RESULTS: PPARγ gene and protein in aortic wall and plaque of apoE-knock out mice were more significant than that in the same aged C57BL/6J mice (P<0.05). PPARγ expression at 40-week-old apoE-knock out mice was most significant and very low in C57BL/6J mice. More PPARγ expression of gene and protein at 20-week-old C57BL/6J mice than 40-week-old C57BL/6J mice were observed. Compared with 20-week-old apoE^-/- mice, the lipid pool in aortic plaque at 40-week-old apoE^-/- mice were increased remarkably, while elastic fiber, collagen and proteoglycan in plaque were decreased and aortic remodeling was very significant. Even, upregulation of MOMA-2 and downregulation of SM-actin were also detected in latter (P<0.05). In addition to SMC of aortic tunica media, PPARγ also expressed in SMC and macrophages in the aortic plaque of apoE^-/- mice. PPARγ was very enriched in lipid pool of the plaque. CONCLUSION: PPARγ expression level decreases with aging in C57BL/6J mice, while increases with plaque progression in apoE-knock out mice. There is positive correlation between PPARγ expression and lipid composition in plaque. The observed upregulation of PPARγ gene expression in aortic plaque may be a compensatory behavior and protective mechanism in apoE-knock out mice.     

Changes of BMP signaling pathway in mammary glands of mice with mammary hyperplasia

AIM: To determine the expression patterns of bone morphogenetic protein (BMP) signaling components in the mammary glands with hyperplasia (MGH) and the activation of this signaling pathway. METHODS: The female C57BL/C mice (8-weeks-old) were randomly divided into control group and hormone group with 15 mice in each group. The mice in control group were treated with PBS, while the mice in hormone group were intragastric administration with estradiol valerate (2.5 mg/kg) for 25 d, followed by progesterone (4 mg/kg) peritoneal injection for 5 d. At the end of treatments, the mammary glands were collected to determine the morphological changes, the mRNA expression of BMP signaling components and the phosphorylation level of Smad1/5/9. RESULTS: In MGH, a part of BMP signaling pathway molecules were differentially expressed (P<0.05), including BMP ligands BMP2, 4, 5, 6, 7, 9, 13 and 14, BMP receptor BMPR1A, and antagonists Chrdl1 and Twsg, whereas the expression levels of some molecules, such as BMP3, BMP12, BMPR1B, BMPR2, Chrd, Chrdl2 and Noggin, were not altered. The phosphorylation levels of Smad1/5/9 was up-regulated in MGH (P<0.05). CONCLUSION: BMP signaling pathway is activated in MGH through the abnormal expression of its components. BMP signaling pathway may be a new target for MGH therapy.