Sinomenine reduces MPP+-induced damage in SK-N-SH cells via ANRIL/miR-626 signaling pathway

AIM To investigate the effect of sinomenine (SN) on the damage of human neuroblastoma SK-N-SH cells induced by 1-methyl-4-4 phenylpyridine (MPP⁺) and its mechanism for exploring the pathogenesis of Parkinson disease. METHODS SN was used to treat MPP⁺-induced SK-N-SH cells. The levels of malondialdehyde (MDA) and glutathione (GSH) in cell culture supernatants were measured by ELISA. The apoptosis was analyzed by flow cytometry. The protein expression levels of Bcl-2 and Bax were determined by Western blot. The expression levels of long noncoding RNA ANRIL and microRNA-626 (miR-626) were detected by RT-qPCR. Dual-luciferase reporter assay was used to evaluate the relationship between ANRIL and miR-626. After ANRIL small interfering RNA was transfected into SK-N-SH cells, the effects of ANRIL expression knock-down on MPP⁺-induced SK-N-SH cell apoptosis, the protein expression levels of Bcl-2 and Bax, and the levels of MDA and GSH in cell culture supernatants were examined. RESULTS After treatment with MPP⁺, the apoptotic rate, Bax protein level and ANRIL expression in SK-N-SH cells were increased (P<0.05), and the Bcl-2 protein level and miR-626 expression were decreased (P<0.05). The level of MDA in cell culture supernatants was increased (P<0.05), and the level of GSH was decreased (P<0.05). After SN treatment or ANRIL expression knock-down, decreased apoptotic rate, Bax protein level and ANRIL expression (P<0.05), and increased Bcl-2 protein level and miR-626 expression in MPP⁺-induced SK-N-SH cells were observed (P<0.05). The level of MDA in the cell culture supernatants was decreased (P<0.05), and the level of GSH was increased (P<0.05). CONCLUSION SN attenuates MPP⁺-induced damage in SK-N-SH cells by regulating ANRIL/miR-626 signaling pathway.     

Expression and function of circular RNA_0000231 in non-small-cell lung cancer

AIM: To investigate the expression and function of circular RNA_0000231 (circ_0000231) in non-small-cell lung cancer (NSCLC). METHODS: RT-qPCR was used to detect the expression of circ_0000231 in the NSCLC tissues and cell lines. circ_0000231 small interfering RNA (si-circ_0000231) or negative control siRNA of circ_0000231 (NC) was transfected into the NSCLC cells. The proliferation and apoptosis of the NSCLC cells were detected by CCK-8 assay, colony formation assay and flow cytometry, respectively. The expression of cyclin D1 (CCND1) and anti-apoptotic protein Bcl-2 were determined by RT-qPCR and Western blot. RESULTS: The expression of circ_0000231 in the NSCLC tissues and cell lines was significantly up-regulated compared with precancerous tissues and lung epithelial cells BEAS-2B (P<0.05). After transfection of NSCLC cells with si-circ_0000231, the cell viability, colony formation numbers were significantly decreased, and the apoptotic rate in si-circ_0000231 group was significantly increased as compared with NC group (P<0.01). In addition, the results of RT-qPCR and Western blot showed that transfection of si-circ_0000231 inhibited the expression of CCND1 and Bcl-2 (P<0.01). CONCLUSION: The expression of circ_0000231 is significantly increased in the NSCLC tissues and cells. Knock-down of circ_0000231 expression significantly inhibits the proliferation of NSCLC cells.     

Expression of histone chaperone ASF1B in prostate cancer cells and its effect on cell viability in vitro

AIM To investigate the expression of histone chaperone anti-silencing function 1B （ASF1B） in prostate cancer cells and its effect on cell viability in vitro. METHODS Human prostate cancer PC-3 cells were used， and knockdown of ASF1B was conducted by small interfering RNA （siRNA） transfection into the cells. The cells were divided into control group， siRNA negative control vector （mock） group and siRNA-ASF1B group. The viability of the PC-3 cells treated with ASF1B-siRNA for 12， 24 and 48 h was measured by MTT assay. Flow cytometry was used to analyze cell apoptosis and cell cycle distribution. The mRNA expression of apoptosis-related molecules was detected by RT-qPCR， and the expression levels of MAPK/JNK/ERK signaling pathway-related proteins were determined by Western blot. RESULTS The protein level of ASF1B in the normal cells （benign prostatic hyperplasia） was significantly lower than that in the PC-3 cells （P<0.01）. Compared with control group and mock group， the protein expression level of ASF1B in the PC-3 cells transfected with siRNA-ASF1B plasmid and the viability of the PC-3 cells were significantly decreased （P<0.01）. The apoptotic rate of the PC-3 cells transfected with siRNA-ASF1B plasmid was significantly higher than that in control group （P<0.01）， and the cell cycle was arrested at G₁ phase. The mRNA levels of p53， caspase-3， Bax and PARP-1 in the PC-3 cells transfected with siRNA-ASF1B plasmid were up-regulated compared with those in control group and Mack group （P<0.01）. In addition， the protein levels of MAP2K4 and p-JNK in the PC-3 cells in siRNA-ASF1B group were significantly higher than those in mock group （P<0.01）， while the protein level of p-ERK was significantly lower than that in mock group （P<0.01）. CONCLUSION ASF1B silencing induces G₁ arrest and promotes apoptosis of PC-3 cells. Activating MAPK/JNK/ERK signaling pathway may be a possible contributor to the anti-prostate cancer effect of siRNA-ASF1B.     

Effect of Herba Taxilli extracts combined with miR-375 on viability and apoptosis of osteoarthritic chondrocytes

AIM To study the effects of extracts of Herba Taxilli (Sangjisheng, SJS) on the viability and apoptosis of osteoarthritic chondrocytes and the underlying mechanism. METHODS Human primary osteoarticular chondrocytes (RPOC) were divided into control group, interleukin-1β (IL-1β) group, IL-1β+low-dose extracts of SJS (SJS-L) group, IL-1β+medium-dose extracts of SJS (SJS-M) group, IL-1β+high-dose extracts of SJS (SJS-H) group, IL-1β+anti-miR-NC group, IL-1β+anti-miR-375 group, IL-1β+SJS-H+miR-NC group, IL-1β+SJS-H+miR-375 group. The cell viability was measured by MTT assay, apoptosis was analyzed by flow cytometry, miR-375 expression was detected by qPCR, and the protein levels of cyclin D1, P21, Bcl-2, Bax and caspase-3 were determined by Western blot. RESULTS Compared with control group, the viability of RPOC at 24 h, 48 h and 72 h and the protein expression levels of cyclin D1 and Bcl-2 were significantly decreased (P<0.05), the protein levels of P21, Bax and caspase-3, the apoptotic rate and the expression level of miR-375 were remarkably increased in IL-1β group(P<0.05). Compared with IL-1β group, the cell viability at 24 h, 48 h and 72 h and the protein expression of cyclin D1 in the RPOC were greatly increased (P<0.05), while the expression of P21 was significantly decreased in IL-1β+SJS-M group and IL-1β+SJS-H group(P<0.05).The apoptotic rate, Bax, caspase-3 protein and miR-375 expression were obviously decreased (P<0.05), and Bcl-2 protein level was significantly increased in IL-1β+SJS-H group compared with IL-1β group(P<0.05). Compared with IL-1β+anti-miR-NC group, the expression of miR-375, the protein levels of P21, Bax, caspase-3 and the apoptotic rate in the RPOC of IL-1β+anti-miR-375 group were markedly decreased (P<0.05), while the cell viability at 24 h, 48 h and 72 h and the protein levels of cyclin D1 and Bcl-2 were significantly increased (P<0.05). Over-expression of miR-375 reversed the effects of extracts of SJS on the viability and apoptosis of RPOC with IL-1β stimulation. CONCLUSION The extracts of Herba Taxilli promotes the viability and inhibits apoptosis of RPOC treated with IL-1β, which is related to the regulation of miR-375 expression.     

CHIP participates in high glucose-induced vascular endothelial cell injury

AIM To investigate the effects of carboxy terminus of heat shock protein 70-interacting protein (CHIP) on high glucose (HG)-induced vascular endothelial cell injury. METHODS Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with 5.5 mmol/L glucose (normal glucose， NG) or 25.5 mmol/L glucose (HG) for 24 h. Down-regulation of CHIP expression by RNA interference was conducted. Before the experiment, mannitol was used to eliminate the interference of osmotic pressure. Subsequently, the cells was divided into 4 groups: NG+siRNA NC group, NG+siRNA CHIP group, HG+siRNA NC group, and HG+siRNA CHIP group. Additionally, MTT assay and TUNEL staining were used to detect the viability and apoptosis. The level of endothelin-1 (ET-1) was measured by ELISA, and the level of reactive oxygen species (ROS) was detected by fluorescence probe dihydroethidium. The level of nitric oxide (NO), and the activity of superoxide dismutase (SOD) and inducible nitric oxide synthase (iNOS) in the cells were detected by their respective kits. The mRNA expression of interleukin-8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) was detected by RT-qPCR. The protein levels of CHIP, NADPH oxidase (NOX) 2, NOX4, p38, p65, p-p38, p-p65, Bax and Bcl-2 were determined by Western blot. RESULTS Compared with NG+siRNA NC group, the cell viability was decreased, the apoptosis rate, the mRNA expression of IL-8 and MCP-1, and the level of ROS were increased (P<0.05), the activity of SOD was decreased (P<0.05), while the levels of ET-1, NO and iNOS and the protein levels of p-p38, p-p65 and Bax were increased in HG+siRNA NC group (P<0.05). Compared with HG+siRNA NC group, the inflammatory response, the oxidative stress, the apoptosis rate, and the protein levels of p-p38, p-p65 and Bax were significantly increased in HG+siRNA CHIP group (P<0.05). CONCLUSION Down-regulation of CHIP expression aggravates HG-induced vascular endothelial cell injury.     

High expression of BIRC5 enhances cell viability,inhibits apoptosis and is associated with poor prognosis in gastric cancer

AIM To investigate the expression of baculoviral inhibitor of apoptosis protein repeat-containing protein 5 （BIRC5） in gastric cancer tissue and its relationship with prognosis of gastric cancer patients， and to explore the effect of BIRC5 knock-down on the viability and apoptosis of gastric cancer cells. METHODS The expression of BIRC5 was detected by immunohistochemistry in 67 cases of gastric cancer tissues and paracancerous tissues for analyzing the relationships with clinicopathological characteristics. The mRNA and protein expression levels of BIRC5 in gastric carcinoma cell lines （AGS， MKN-1 and MGC-803） and normal gastric epithelial cell line GES-1 were detected by RT-qPCR and Western blot. The AGS cells were divided into blank group （no treatment）， Ctr-sh group （blank plasmid transfection） and BIRC5-sh group （BIRC5-shRNA plasmid transfection）. The interference efficiency of BIRC5-shRNA was evaluated by Western blot. The cell viability was measured by MTT assay， the apoptosis was analyzed by flow cytometry， and the levels of apoptosis-related proteins cleaved caspase-3， Bax and Bcl-2 were determined by Western blot. RESULTS BIRC5 was mainly expressed in cytoplasm， and the positive expression rate of BIRC5 in the gastric cancer tissues was higher than that in the adjacent tissues （P<0.01）. The positive rates of BIRC5 in the gastric cancer patients at TNM Ⅲ~Ⅳ stages and with lymph node metastasis were higher than those in the patients at TNM Ⅰ~Ⅱ stages and without lymph node metastasis， respectively （P<0.05）. The survival time of the patients with positive BIRC5 expression was shorter than that of the patients with negative BIRC5 expression （P=0.011 2）. The cell viability in BIRC5-sh group was lower than that in blank group and Ctr-sh group at time points of 48， 72 and 96 h. The apoptotic rate in BIRC5-sh group was increased compared with blank group and Ctr-sh group. The protein levels of cleaved caspase-3 and Bax in BIRC5-sh group were higher than those in blank group and Ctr-sh group， while the protein expression of Bcl-2 in BIRC5-sh group was lower than that in blank group and Ctr-sh group （P<0.05）. CONCLUSION High expression of BIRC5 in gastric cancer indicates poor prognosis. BIRC5 promotes the growth of gastric cancer cells and inhibits apoptosis.     

矮化中间砧‘宫藤富士’苹果栽植密度对树体生长、冠层光照和果实产量的影响

2011 年春季定植的矮化中间砧苹果成品苗（3 年根 1 年干的‘宫藤富士’/SH6/平邑甜茶）为试材，设置 7 种不同的栽植密度（株行距分别为 1 m × 3 m、1.5 m × 3 m、2 m × 3 m、0.75 m × 4 m、1 m × 4 m、1.25 m × 4 m 和 1.5 m × 4 m），细纺锤形整枝修剪，自栽植第 2 年，连续 7 年调查 7 种栽植密度对树体生长、冠层光照分布、果实产量和品质的影响。随着树龄的增长，不同栽植密度下树干粗度和总枝量逐年增加，不同处理间树干粗度无显著差异，第 7 年 1 m × 3 m 和 0.75 m × 4 m 两个栽植密度下树体总枝量超过 140 万条 · hm-2，第 8 年均超过 140 万条 · hm-2。栽植前期（第 2 ~ 4 年）各栽植密度树体短枝比例不断增加，长枝比例不断减少，第 5 年各栽植密度枝类组成趋于稳定；综合稳产 3 年（第 6 ~ 8 年）树体的枝类组成数据，4 m 行距的短枝比例明显高于 3 m 行距，长枝比例略低。树体冠层平均相对光照强度由高到低的株行距处理依次为 1.5 m × 4 m（63.87%）、1.25 m × 4 m（61.44%）、2 m × 3 m（61.27%）、1 m × 4 m（59.19%）、0.75 m × 4 m（55.79%）、1.5 m × 3 m（53.67%）和 1 m × 3 m（49.37%）；相同栽植株数下，4 m 行距处理低光效（相对光照强度小于 40%）的区域比例显著小于 3 m 行距。比较前 5 年的累计产量，以行距 4 m 和 1 m × 3 m 的最高。综合稳产 3 年的结果情况，大果率（单果质量 > 200 g 的果实产量占总产量的比例）以 4 m 行距和 2 m × 3 m 的最高。各栽植密度下的果实的可溶性固形物含量、固酸比、果形指数和果实硬度均无显著差异。综上，采用 4 m 行距，1 ~ 1.25 m 株距，树体成形快，稳产后树体结构合理，冠层光照充足，低效光区比例少，前期产量高。     

Effect of 27nt-miRNA on apoptosis of human umbilical vein endothelial cells induced by oxidized low-density lipoprotein

AIM To investigate the effect of 27nt-miRNA （27nt-miR） on apoptosis of human umbilical vein endothelial cells （HUVECs） induced by oxidized low-density lipoprotein （Ox-LDL） and its underlying mechanism. METHODS HUVECs were cultured in vitro and grouped as below： normal control group， Ox-LDL group， 27nt-miR+Ox-LDL group， anti-27nt-miR+Ox-LDL group and negative control+Ox-LDL group. The cells in Ox-LDL group were treated with Ox-LDL at 40 mg/L for 48 h， while those in normal control group were untreated but cultured normally. The cells in 27nt-miR+Ox-LDL group， anti-27nt-miR+Ox-LDL group and negative control+Ox-LDL group were transfected with their corresponding lentiviral vectors under the same procedure， followed by treatment with Ox-LDL at 40 mg/L for 48 h to induce apoptosis. The cell viability was measured by CCK-8 assay. The migration capacity was detected by scratch assay. The caspase-3 activity was measured by caspase-3 activity assay kit. The apoptotic rate was analyzed by Hoechst 33258 and flow cytometry. The mRNA and protein expression levels of Bcl-2， Bax and caspase-3 were determined by RT-qPCR and Western blot. RESUITS： Compared with negative control+Ox-LDL group， the cell viability and migration ability were significantly decreased by over-expression of 27nt-miR in the HUVECs （P<0.05）， while the activity of caspase-3 and apoptosis induced by Ox-LDL were significantly increased （P<0.05）. Furthermore， the mRNA and protein expression levels of Bax and caspase-3 were significantly up-regulated （P<0.05）， and the mRNA and protein expression level of Bcl-2 was down-regulated in 27nt-miR+Ox-LDL group （P<0.05）. Meanwhile， all the above indexes showed an opposite tendency in anti-27nt-miR+Ox-LDL group. CONCLUSION 27nt-miR promotes Ox-LDL-induced apoptosis and inhibits the viability and migration of HUVECs in vitro， possibly through regulating the expression of apoptotic/anti-apoptotic proteins such as Bax，caspase-3 and Bcl-2.     

Effect of compound of Epimedium, Astragalus and Radix Puerariae on expression of ADAM10 in Aβ-induced hippocampal neuron HT22 cells with or without hepcidin expression knock-down

AIM To explore the effect of compound of Epimedium, Astragalus and Radix Puerariae on the expression of a disintegrin and metalloproteinase 10 （ADAM10） in Aβ-induced hippocampal neuron HT22 cells with or without hepcidin （HAMP） expression knock-down for analyzing the pathogenesis of Alzheimer disease （AD） at cell level. METHODS Hippocampal neuron HT22 cells were cultured in vitro and randomly divided into 7 groups： control group, Aβ group （Aβ_25-35-induced HT22 cells）, RNAi group （HAMP gene was silenced in HT22 cells）, Aβ+RNAi group （HAMP gene expression in Aβ_25-35-induced HT22 cells was silenced）, Aβ+TCM group （Aβ_25-35-induced HT22 cells were treated with Epimedium, Astragalus root and Radix Puerariae effective components）, RNAi+TCM group （HT22 cells with HAMP gene silence were treated with Epimedium, Astragalus root and Radix Puerariae effective components） and Aβ+RNAi+TCM group （Aβ_25-35-induced HT22 cells with HAMP gene silence were treated with Epimedium, Astragalus root and Radix Puerariae effective components）. The silence efficiency of HAMP siRNA was detected by qPCR and Western blot. The ADAM10 expression in each group was determined by immunofluorescence, qPCR and Western blot. RESULTS The HAMP siRNA-3 sequence had the highest interference efficiency. Compared with control group, the expression levels of ADAM10 in Aβ group, RNAi group and Aβ+RNAi group were decreased （P<0.05）. Compared with Aβ group,the expression levels of ADAM10 in Aβ+RNAi group was also decreased （P<0.05）, and the expression levels of ADAM10 in Aβ+TCM group was increased （P<0.05）. Compared with RNAi group, the expression levels of ADAM10 in Aβ+RNAi group was decreased （P<0.05）, while the expression levels of ADAM10 in RNAi+TCM group was increased （P<0.05）. Compared with Aβ+RNAi group, the expression levels of ADAM10 in Aβ+RNAi+TCM group was increased （P<0.05）. CONCLUSION The effective components of Epimedium, Astragalus and Radix Puerariae compound promotes the expression of ADAM10 in Aβ_25-35-induced HT22 cells, which mechanism may be related to the expression of HAMP.     

miR-556-3p regulates viability,migration and invasion of endometrial cancer cells by targeting SASH1

AIM To investigate whether microRNA-556-3p （miR-556-3p） regulates the viability, migration and invasion of endometrial cancer cells by targeting SASH1 gene. METHODS The expression of miR-556-3p, and the mRNA and protein levels of SASH1 in endometrial cancer tissues were detected by RT-qPCR and Western blot. Anti-miR-556-3p or pcDNA-SASH1 was transfected into endometrial cancer Ishikawa cells. The cell viability was detected by MTT assay, the migration and invasion abilities of the cells were detected by Transwell chamber method, and the protein expression levels of cyclin D1, p21, matrix metalloproteinase-2 （MMP-2） and MMP-9 were detected by Western blot. StarBase prediction and dual-luciferase reporter experiments were used to analyze the targeting relationship between miR-556-3p and SASH1. Anti-miR-556-3p and si-SASH1 were co-transfected into the Ishikawa cells, and their effects on cell viability, migration and invasion were examined by the methods described above. RESULTS Compared with adjacent tissues, the expression of miR-556-3p in endometrial cancer tissues was increased significantly, and the expression of SASH1 at mRNA and protein levels was decreased significantly （P<0.05）. Inhibition of miR-556-3p expression or induction of SASH1 over-expression obviously reduced the viability of Ishikawa cells, the number of migratory cells, the number of invasive cells and the protein levels of cyclin D1, MMP-2 and MMP-9, and dramatically increased the protein level of p21 （P<0.05）. miR-556-3p targeted SASH1 and negatively regulated its expression. Knock-down of SASH1 expression reversed the inhibitory effect of miR-556-3p expression inhibition on the viability, migration and invasion of Ishikawa cells. CONCLUSION Inhibition of miR-556-3p expression suppresses the viability, migration and invasion of endometrial cancer cells. The mechanism is related to the regulation of its target gene SASH1.     

STC-1 mediates proliferation and apoptosis of gastric cancer cells through Bcl-2

AIM To investigate the effect of stanniocalcin-1 （STC-1） on the proliferation and apoptosis of gastric cancer AGS cells and the role of Bcl-2 in these processes. METHODS The AGS cells were transfected with the plasmids for STC-1 knockdown or over-expression. The cell proliferation was measured by MTT assay and colony formation assay. The migration ability was detected by scratch assay. Apoptosis was analyzed by Hoechst 33342 staining and flow cytometry with annexin V-FITC/PI double staining. The protein expression of Bcl-2， survivin， caspase-3 and cleared caspase-3 was determined by Western blot. The mRNA expression levels of STC-1 and Bcl-2 in 20 cases of clinical gastric cancer tissues and adjacent tissues were detected by RT-qPCR， and the correlation between them was analyzed by Pearson method. RESULTS After over-expression of STC-1， the proliferation and migration abilities of the AGS cells were increased， the expression of Bcl-2 and survivin was increased， while the expression of caspase-3 and cleared caspase-3 was decreased （P<0.05）. After knockdown of STC-1， the proliferation and migration abilities of the AGS cells were decreased， the expression of Bcl-2 and survivin was decreased， while the expression of caspase-3 and cleared caspase-3 was increased （P<0.05）. The mRNA expression levels of STC-1 and Bcl-2 in the gastric cancer tissues were higher than those in the adjacent tissues. Pearson correlation analysis showed that there was a positive correlation between STC-1 and Bcl-2 mRNA expression in the cancer tissues （r=0.308， P=0.011）. CONCLUSION STC-1 may regulate the biological function of gastric cancer cells by altering the expression level of Bcl-2.     

Effect of abnormal expression of PDK4 on glycolysis and proliferation in prostate cancer cells

AIM To investigate the expression of pyruvate dehydrogenase kinase 4 （PDK4） in prostate cancer tissue and its effect on glycolysis and growth of prostate cancer cells. METHODS Immunohistochemistry was used to compare the expression differences of PDK4 protein in benign prostatic hyperplasia （BPH） and prostate cancer tissues. The expression levels of PDK4 in normal prostatic epithelial cells （RWPE-1） and different prostate cancer cell lines （PC3， LNCaP， DU145 and C4-2） were detected by RT-qPCR and Western blot. Recombinant plasmid carrying PDK4-shRNA was constructed， and the expression of PDK4 in prostate cancer PC3 cells was down-regulated by transfection with PDK4-shRNA. The changes in glycolysis level of PC3 cells before and after transfection were determined by cell glycolysis kit， and the effects of PDK4 on the viability and cell cycle distribution of PC3 cells were detected by CCK-8 assay and flow cytometry. RESULTS In prostate cancer tissues， the expression level of PDK4 protein was significantly higher than that in BPH tissues （P<0.05）， and the analysis of immunohistochemical score showed that prostate cancer tissues with high Gleason score displayed significantly higher PDK4 expression than those with low Gleason score （P<0.05）. Compared with normal prostatic epithelial cells， RT-qPCR and Western blot results indicated that the expression level of PDK4 was also significantly increased in prostate cancer cell lines （P<0.05）. In addition， CCK-8 assay results showed that the viability of prostate cancer PC3 cells was significantly decreased after knockdown of PDK4 expression （P<0.05）. The results of flow cytometry demonstrated that knockdown of PDK4 expression in PC3 cells resulted in a notable increase in G₀/G₁ phase arrest （P<0.05）. CONCLUSION PDK4 is highly expressed in prostate cancer tissues and cell lines， and significantly increases in prostate cancer with high Gleason score. In addition， down-regulation of PDK4 expression significantly inhibits glycolysis and growth of prostate cancer cells， resulting in cell cycle arrest at G₀/G₁ phase.     

Effects of platelet-rich plasma on chondrocyte apoptosis and NLRP3/IL-1β signaling pathway in rabbits with osteoarthritis

AIM To explore the effect of platelet-rich plasma (PRP) on rabbit osteoarthritis and its possible mechanism. METHODS The rabbits with knee osteoarthritis were prepared and then divided into model group, sodium hyaluronate (SH) group and PRP group, and another sham operation group was set up, with 6 rabbits in each group. The gross morphological changes of rabbit cartilage were observed. HE staining was used to evaluate the pathomorphological changes of the cartilage. TUNEL staining was used to detect the apoptosis of chondrocytes. The expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/interleukin-1β （IL-1β） signaling pathway-related molecules was observed by immunohistochemical staining, and the protein levels of caspase-3, Bcl-2 and Bax were determined by Western blot. Chondrocytes were isolated and processed according to grouping, and the NLRP3 and IL-1β levels of the cells were measured by ELISA. RESULTS Compared with sham operation group, Pelletier score, Mankin score, chondrocyte apoptotic rate, the positive protein expression rates of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in model group were increased significantly (P<0.05), while the protein expression of Bcl-2 was decreased significantly (P<0.05). Compared with model group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax in SH group and PRP group were decreased significantly (P<0.05), while the protein expression of Bcl-2 was increased significantly (P<0.05). In PRP group, Pelletier score, Mankin score, the apoptotic rate of chondrocytes, the positive protein expression rates of NLRP3, ASC, caspase-1 and IL-1β, and the protein levels of caspase-3 and Bax were lower than those in SH group, while the protein expression of Bcl-2 was higher than that in SH group (P<0.05). Compared with control group, the expression of NL?RP3 and IL-1β in MCC950 (NLRP3 ihibitor) group were significantly reduced (P<0.05), the expression of NLRP3 in eucalyptol (IL-1β inhibitor) group was not significantly changed (P>0.05), and the expression of IL-1β was significantly reduced (P<0.05). CONCLUSION Platelet-rich plasma promotes the repair of cartilage in osteoarthritis rabbits, which has better effect than SH. The mechanism may be related to the inhibition of NLRP3/IL-1β pathway and the reduction of chondrocyte apoptosis.     

SUMO-specific protease 3 aggravates CaPO4-induced mouse abdominal aortic aneurysm formation by promoting macrophage polarization

AIMTo investigate the role of SUMO-specific protease 3 (SENP3) in macrophage polarization and calcium phosphate (CaPO₄)-induced abdominal aortic aneurysm (AAA) formation in mice. METHODS（1） Bone marrow-derived monocytes (BMDMs) in Senp3^flox/flox (wild-type, WT) mice and Senp3^flox/flox; Lyz2-Cre (monocyte-specific SENP3 knockout, i.e. conditioned knockout, cKO) mice were isolated and induced for M1 and M2 polarization. The mRNA and protein expression level of SENP3 were detected by RT-qPCR, Western blot and immunocytofluorescence, and the differential distribution of M1/M2 BMDMs from WT and cKO mice was analyzed. （2） CaPO₄ was administrated to induce AAA model in 8~12-week-old male WT and cKO mice. The AAA incidence, survival rate and maximal aortic diameter were analyzed between the 2 groups. Aortic aneurysm tissues were collected for pathological analysis, and the expression levels of SENP3, interleukin-1β (IL-1β), tumor necrosis factor-α (TNFα), IL-6 and matrix metalloproteinases-9 (MMP-9) were measured by RT-qPCR and Western blot. Dihydroethidium staining in situ in frozen sections was used to analyze the production of reactive oxygen species (ROS). （3） To explore the potential mechanisms, Western blot and co-immunoprecipitation were used to verify the de-SUMO modification of mitogen-activated protein kinase kinase 7 (MKK7) induced by SENP3. Besides, BMDMs were transfected with Flag-MKK7 wild type (Flag-MKK7 WT) and SUMO-modified site K18 mutant (Flag-MKK7 K18R mutant), and then M1 polarization of the cells was induced. The protein levels of p-JNK and MMP-9 in the 2 groups were determined by Western blot. RESULTS(1) SENP3 expression was up-regulated in M1 polarized macrophages (P<0.01), but was down-regulated in M2 polarized macrophages (P<0.01). The expression of SENP3 was decreased during the transformation of M1 to M2 in the macrophages (P<0.01), but was significantly up-regulated during the opposite process (P<0.01). Besides, more M1 macrophages and less M2 macrophages after induction were observed in the BMDMs from cKO mice than those from WT mice. (2) SENP3 expression was up-regulated in AAA tissues (P<0.05). The AAA incidence of cKO mice was significantly reduced after CaPO₄ induction (P<0.01), the survival rate was significantly improved (P<0.05), and maximal aortic diameter was significantly reduced in cKO group (P<0.01). The levels of IL-1β, IL-6 and TNFα, and the production of ROS were significantly down-regulated (P<0.01), meanwhile MMP-9 expression was also down-regulated in cKO mice (P<0.05). (3) the SUMO2/3 modification of MKK7 was reduced during M1 polarization, and MKK7 interaction with SENP3 was enhanced. Significantly up-regulated protein level of p-JNK and MMP-9 were verified in the M1 macrophages transfected with Flag-MKK7 K18R mutant (P<0.05). CONCLUSION SENP3 activates the MAPK/JNK pathway via de-SUMOylation of MKK7, regulates the M1/M2 polarization of macrophages and promotes the protein level of MMP-9, thus aggravating AAA formation.