Electroacupuncture Improves Blood-Brain Barrier and Hippocampal Neuroinflammation in SAMP8 Mice by Inhibiting HMGB1/TLR4 and RAGE/NADPH Signaling Pathways / 中国结合医学杂志

OBJECTIVE@#To investigate the molecular mechanisms underlying the beneficial effect of electroacupuncture (EA) in experimental models of Alzheimer's disease (AD) in vivo.@*METHODS@#Senescence-accelerated mouse prone 8 (SAMP8) mice were used as AD models and received EA at Yingxiang (LI 20, bilateral) and Yintang (GV 29) points for 20 days. For certain experiments, SAMP8 mice were injected intravenously with human fibrin (2 mg). The Morris water maze test was used to assess cognitive and memory abilities. The changes of tight junctions of blood-brain barrier (BBB) in mice were observed by transmission electron microscope. The expressions of fibrin, amyloid- β (Aβ), and ionized calcium-binding adapter molecule 1 (IBa-1) in mouse hippocampus (CA1/CA3) were detected by reverse transcription-quantitative polymerase chain reaction (qRT-PCR), Western blot or immunohistochemical staining. The expression of fibrin in mouse plasma was detected by enzyme-linked immunosorbent assay. The expressions of tight junction proteins zonula occludens-1 and claudin-5 in hippocampus were detected by qRT-PCR and immunofluorescence staining. Apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining.@*RESULTS@#Fibrin was time-dependently deposited in the hippocampus of SAMP8 mice and this was inhibited by EA treatment (P<0.05 or P<0.01). Furthermore, EA treatment suppressed the accumulation of Aβ in the hippocampus of SAMP8 mice (P<0.01), which was reversed by fibrin injection (P<0.05 or P<0.01). EA improved SAMP8 mice cognitive impairment and BBB permeability (P<0.05 or P<0.01). Moreover, EA decreased reactive oxygen species levels and neuroinflammation in the hippocampus of SAMP8 mice, which was reversed by fibrin injection (P<0.05 or P<0.01). Mechanistically, EA inhibited the promoting effect of fibrin on the high mobility group box protein 1 (HMGB1)/toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE)/nicotinamide adenine dinucleotide phosphate (NADPH) signaling pathways (P<0.01).@*CONCLUSION@#EA may potentially improve cognitive impairment in AD via inhibition of fibrin/A β deposition and deactivation of the HMGB1/TLR4 and RAGE/NADPH signaling pathways.

The Value of Serum HMGB1 and sRAGE in the Diagnosis, Efficacy Monitoring and Prognosis of Newly Diagnosed Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To evaluate the value of high mobility group protein B1 (HMGB1) and soluble receptor for advanced glycation end products (sRAGE) in the diagnosis, efficacy monitoring and prognosis of newly diagnosed multiple myeloma (MM) patients.@*METHODS@#Fifty newly diagnosed MM patients before and after chemotherapy and 50 hematological outpatients from October 2018 to May 2020 were selected. Enzyme linked immunosorbent assay (ELISA) was used to detect the serum HMGB1 and sRAGE levels of the patients. ROC was used to further analyze the efficacy of serum HMGB1 and sRAGE levels on the diagnosis of MM. At the same time, the serum levels of HMGB1 and sRAGE before and after chemotherapy were compared, and their values in the evaluation of curative effect of MM patients were analyzed. According to the mean values of serum HMGB1 and sRAGE, all the patients were divided into different groups, the clinical characteristics and survival status of the patients were compared.@*RESULTS@#Before treatment the serum HMGB1 level of the patients in MM group was higher than that in control group, while sRAGE level was lower (t=11.363,6.127, P<0.001). The AUC of serum HMGB1 and sRAGE in the MM patients was 0.955 and 0.811, respectively. After 3 courses of chemotherapy, HMGB1 level of the patients in CR group was lower than before chemotherapy, while in PD group was higher, as well as sRAGE level of the patients in PR group (P<0.05). There were significant differences in R-ISS stage, HGB, CRP, ESR, CD56, CD117, D13S319 deletion between HMGB1 high expression group and HMGB1 low expression group (χ2=3.920, 6.522, 6.65, 4.16, 3.945, 6.65, 4.16, P<0.05), while there were significant differences in ISS stage, CRP and CD56 between sRAGE low expression group (28 cases) and sRAGE high expression group (22 cases) (χ2=4.565, 4.711, 5.547, P<0.05). Kaplan-Meier survival analysis showed that the patients in HMGB1 low expression group had better survival condition, for PFS Tlow>Thigh (χ2=9.470, P<0.05), and for OS Tlow>Thigh (χ2=7.808, P<0.05); there was no difference in the survival of sRAGE high expression group and low expression group, for PFS Tlow<Thigh (χ2=1.661, P>0.05), and for OS Tlow<Thigh (χ2=2.048, P>0.05). Cox analysis showed that LDH and HMGB1 were the factors affecting the prognosis of the patients, and both of them affected PFS (HR=2.771, 95% CI: 1.002-7.662, P=0.049; HR=6.022, 95% CI: 1.689-21.470, P=0.006), while HMGB1 also affected OS (HR=4.275, 95% CI: 1.183-15.451, P=0.027).@*CONCLUSION@#The serum HMGB1 and sRAGE have certain auxiliary value for the diagnosis and curative effect monitoring of newly diagnosed MM patients, and serum HMGB1 is expected to be an auxiliary detection index for the prognosis of MM.

Stingless bee propolis, metformin, and their combination alleviate diabetic cardiomyopathy

Abstract Background and aim: Stingless bee propolis, a resinous compound processed by mandibular secretion of stingless bees, is used for maintenance of hygiene and stability of beehives. Research on stingless bee propolis shows therapeutic properties attributed to polyphenols exhibiting antioxidative, antihyperglycemic and antiischemic effect. However, the cardioprotective effect of stingless bee propolis on diabetic cardiomyopathy is unknown. Methods: Adult male Sprague Dawley rats were randomised to five groups: normal group, diabetic group, diabetic given metformin (DM+M), diabetic given propolis (DM+P) and diabetic given combination therapy (DM+M+P) and treated for four weeks. Body weight, fasting blood glucose, food and water intake were taken weekly. At the end of experiment, biomarkers of oxidative damage were measured in serum and heart tissue. Antioxidants in heart tissue were quantified. Part of left ventricle of heart was processed for histological staining including Haematoxylin and Eosin (H&E) stain for myocyte size and Masson's Trichrome (MT) stain for heart fibrosis and perivascular fibrosis. Results: Propolis alleviated features of diabetic cardiomyopathy such as myocyte hypertrophy, heart fibrosis and perivascular fibrosis associated with improvement in antioxidative status. Conclusion: This study reports beneficial effect of propolis and combination with metformin in alleviating histopathological feature of diabetic cardiomyopathy by modulating antioxidants, making propolis an emerging complementary therapy.

Activación inmune por productos finales de glicación avanzada

Con el objetivo de revisar los avances recientes en la biología de los productos de glica- ción avanzada y su papel en diversas patologías de alta relevancia en salud pública, se realizó una búsqueda dirigida de la bibliografía entre los años 2000 al 2021 en la base de datos PubMed (NCBI) y se usaron como palabras clave "advanced glycation end pro- ducts". Se ha demostrado que el receptor de productos de glicación avanzada induce una activación sostenida del factor de transcripción proinflamatorio NF-kB y suprime una serie de funciones autorreguladoras endógenas. Este efecto influye negativamente en una gran variedad de patologías como diabetes, autoinmunidad, neurodegeneración y enfermedades infecciosas. La acumulación tisular de productos de glicación avanzada está relacionada con procesos de inflamación crónica y disfunción celular, y constituye un blanco prometedor para el diseño de tratamientos enfocados en esta vía de señali- zación. Actualmente se realizan múltiples ensayos clínicos para determinar su utilidad como marcador de lesiones pulmonares en COVID-19.

To review recent advances in the biology of advanced glycation endproducts and its role in diverse pathologies of high relevance for public health, a survey of the literature from the years 2000 to 2021 was performed in PubMed (NCBI) using the key words "advanced glycation endproducts". It has been demonstrated that the receptor for advanced glyca- tion endproducts (RAGE) induces a sustained activation of the pro-inflammatory tran- scription factor NF-kB and suppresses a series of endogenous self-regulating functions. This affects negatively on a wide variety of pathological conditions such as diabetes, au- toimmunity, neurodegeneration and infectious disease. Tissular accumulation of AGEs is linked to chronic inflammation and cellular dysfunction and constitutes a promising target for the design of treatments focused on this signaling pathway. Multiple clinical trials are currently underway to define its usefulness as a marker of pulmonary lesions in COVID-19.

Associations of high-mobility group box 1 and receptor for advanced glycation end products with acute lung injury in patient with acute aortic dissection

SUMMARY OBJECTIVE: To investigate the associations of high-mobility group box 1 and its specific receptor, receptor for advanced glycation end products with acute lung injury in patients with acute aortic dissection. METHODS: A total of 96 acute aortic dissection patients were divided into acute aortic dissection with acute lung injury group (38 cases) and acute aortic dissection without acute lung injury group (58 cases), according to partial pressure of oxygen/fraction of inspired oxygen. In addition, 44 healthy individuals were selected for the control group. The blood samples were taken. The serum high-mobility group box 1 and receptor for advanced glycation end products levels were detected by enzyme-linked immunosorbent assay, and the partial pressure of oxygen/fraction of inspired oxygen was measured. RESULTS: 24 h after admission, the high-mobility group box 1 and receptor for advanced glycation end products levels in acute aortic dissection with acute lung injury and acute aortic dissection without acute lung injury groups were significantly higher than those in the control group, respectively (p<0.05), and each index in acute aortic dissection with acute lung injury group was significantly higher than that in acute aortic dissection without acute lung injury group (p<0.05). At each time point within 96 h after admission, compared with acute aortic dissection without acute lung injury group, in acute aortic dissection with acute lung injury group, the high-mobility group box 1 and receptor for advanced glycation end products levels were increased, respectively, and the partial pressure of oxygen/fraction of inspired oxygen was decreased. The correlation analysis showed that, in acute aortic dissection patients, the high-mobility group box 1 and receptor for advanced glycation end products levels were negatively correlated with partial pressure of oxygen/fraction of inspired oxygen, respectively (p<0.05). CONCLUSIONS: The serum high-mobility group box 1 and receptor for advanced glycation end products levels may be associated with the occurrence of acute lung injury in acute aortic dissection patients. Monitoring the high-mobility group box 1 and receptor for advanced glycation end products levels can evaluate the risk of acute aortic dissection with acute lung injury.

Soluble receptor for advanced glycation end-products inhibits myocardial fibrosis of ischemia/reperfusion mice / 解剖学报

Objective To investigate the effect of soluble receptor for advanced glycation end-products (sRAGE) on inflammation in myocardial ischemia/reperfusion ( I/R ) mice and its mechanism. Methods Myocardial I/R injury model was conducted by left anterior descending ligation for 30 minutes and reperfusion for 2 weeks in male C57BL/6 mice aged 6-8 weeks. The mice were randomly divided into four groups with five C57BL/6 mice in each group. The cardiac function was detected by echocardiography, the inflammatory cells infiltration was observed by HE staining, the myocardial fibrosis was detected by Masson and Sirius red staining, the expression of galectin-3 was detected by immunohistochemical staining. Results Compared with the sham group, the cardiac function decreased, the inflammatory cells infiltrated increased among the myocardial tissue, the percentage of myocardial fibrosis area increased, and the expression of galectin-3 increased in I/R groups. After exogenous sRAGE treatment, the cardiac function of mice was significantly improved, the inflammatory cells infiltration decreased, the myocardial fibrosis area decreased, and the expression of galectin-3 decreased as well. Conclusion sRAGE may reduce inflammatory cells infiltration in mice heart by inhibiting the expression of galectin-3, and then alleviating myocardial fibrosis during myocardial ischemia/reperfusion injury.

The Effects of Open-Lung Strategy on Lung Injury Markers in Patients under General Anesthesia with Low-tidal-volume Ventilation / 中山大学学报(医学科学版)

@#【Objective】To determine the effects of an open-lung strategy（OLS）comprising moderate positive end- expiratory pressure （PEEP） and intermittent recruitment manoeuvres（RMs） on plasma levels of lung epithelial injury markers［i.e. soluble receptor for advanced glycation end products（sRAGE）and Clara cell protein（CC16）］during low- tidal-volume ventilation for surgery.【Methods】One hundred patients who were undergoing laparoscopic colorectal cancer resection under low-tidal-volume ventilation were enrolled in this study. They were randomly assigned（1∶1）to the OLS group（using PEEP of 6~8 cmH2O and intermittent RM），or the NOLS group（without using PEEP and RM）. Blood samples were taken before anesthesia induction（T1），immediately after surgery（T2）and the postoperative day 3（T3）to measure the plasma concentrations of sRAGE and CC16. 【Results】 Significant differences were not observed in the concentrations of sRAGE and CC16 at T1，T2 and T3 between the two groups（all P > 0.05）. For all the enrolled patients， the concentrations of sRAGE at T2 and T3 were higher than that at T1，the concentration of sRAGE at T3 was higher than that at T2，and the concentration of CC16 at T3 was higher than that at T1 and T2（all P < 0.05）.【Conclusions】In patients under general anesthesia with low-tidal-volume ventilation，the using of an OLS comprising medium PEEP and intermittent RMs can not alter plasma levels of lung epithelial injury markers（sRAGE and CC16）in three days after surgery.

Effect of Betulic Acid on RAGE/NF-κB/iNOS Signaling Pathway Expression in Steatosis Cell / 中国实验方剂学杂志

Objective::To investigate the effect of betulic acid(BA) on steatosis LO2 cells. Method::LO2 cells were intervened with BA at different gradient concentrations (0, 10, 20, 40, 80, 160, 250 μmol·L-1) for 24 hours. methyl thiazolyl tetrazolium(MTT) staining was used to observed cell viability to determine the final concentration of BA. The cells were divided into control, model, dimethylsulfoxide (DMSO) and BA groups, as well as BA groups intervened with low, middle and high concentrations. First, model, DMSO and BA group's cells were cultured in 10% Lipid Mix 1 medium for 24 hours to establish a nonalcoholic fatty liver model. Then, DMSO group and low, medium and high-concentration groups were separately cultured with 0.1%DMSO medium and 20, 40, 80 μmol·L-1 BA medium for 24 hours. And control and model groups were cultured in drug-free medium for 24 hours. Oil red O staining and Nile red staining were used to observe the intracellular lipid droplets. Immunofluorescence was used to detect the protein expression of inducible nitric oxide synthase (iNOS). Western blot was used to detect the protein expression levels of receptor for advanced glycation end-products (RAGE), nuclear factor κB p65 (NF-κB p55) and iNOS. Result::BA within the concentration of 80 μmol·L-1 had no significant toxicity on LO2 cells. Compared with control group, the intracellular lipid droplets were significantly increased in the model group, and the expressions of oxidative stress-related proteins RAGE, NF-κB p65 and iNOS also increased significantly(P<0.05). Compared with model group, the intracellular lipid droplets in DMSO group were similar to those in model group, with no significant difference in the three protein expressions between the two groups. However, the intracellular lipid droplets deposition in the BA group was significantly decreased. And the expressions of RAGE, NF-κB p65 and iNOS proteins in high-concentration BA group were significantly decreased(P<0.05, P<0.01). Conclusion::BA can significantly improve the intracellular fat deposition in LO2 cells, which was probably related to the inhibition of the expressions of oxidative stress-related proteins RAGE, NF-κB p65 and iNOS.

Effect of advanced glycation end products on metabolism of bone tissue cells / 中国组织工程研究

BACKGROUND: With the research and development of bone tissue engineering, it has been found that advanced glycation end products can accumulate in bone tissue and affect the structure and biomechanical properties of bone. At present, many researchers have discovered that advanced glycation end products/receptor for advanced glycation end products can induce pathological changes of osteoblasts, osteoclasts and osteocytes through special mechanisms, thereby leading to imbalance of bone reconstruction, decrease of bone strength and increase of fracture incidence. OBJECTIVE: To review the effects of advanced glycation end products on bone biomechanics and the mechanism of advanced glycation end products/receptor for advanced glycation end products on bone tissue cells. METHODS: The first author searched the relevant articles regarding the effect of advanced glycation end products/receptor for advanced glycation end products on metabolism of bone tissue cells published in PubMed, Web of Science and Medline database from January 2005 to July 2019. The results were limited to English literatures. RESULTS AND CONCLUSION: Finally, 54 representative literatures were selected for summary. The effects of advanced glycation end products on collagen cross-linking can significantly reduce bone strength. Advanced glycation end products/receptor for advanced glycation end products affects bone metabolism through pathological mechanism changes of bone tissue cells, which results in essential changes of bone tissue cells. Finally, it will lead to imbalance of bone metabolism and increase of bone fragility. The osteoporosis is directly related to the activity change of bone tissue cells, but the specific mechanism needs further study. The change of this special mechanism may provide a unique pathological mechanism, diagnosis methods, treatment and prevention strategies for osteoporosis in the future.

The alterations and clinical significance of serum S100A8/A9 and sRAGE in patients with chronic obstructive pulmonary disease / 中华检验医学杂志

Objective@#To analyze the alterations and clinical significance of serum calcium binding protein S100A8/A9 and soluble receptor for advanced glycation end products (sRAGE) levels in patients with chronic obstructive pulmonary disease(COPD).@*Methods@#Enzyme-linked immonosorbent assay was established to detect serum levels of S100A8/A9 and sRAGE in 203 patients with COPD[male166, female 37, aged 52-92 years, average years(69.72±9.079)] and in 41 smoking elderly non-COPD patients[male 35,female 6, aged 55-89 years, average years(68.66±8.74)], and 167 non-smoking healthy subjects as the control group[male 132, female 35, aged 57-92 years, average years(69.13±7.21)] from April 2018 to January 2019. The relationship between the S100A8/A9, sRAGE and clinical biomarkers [the percentage of fored expiratory volume in one second(FEV1) in the predicted value, FEV1/fored vital capacity(FVC), neutrophile granulocyte(NEU)%, pack-year] were investigated. The diagnostic value of S100A8/A9, sRAGE and their combined detection for COPD was analyzed using the subject operating characteristic curve.@*Results@#The serum S100A8/A9 level [(2.70±1.11)μg/ml] in COPD patients was significantly higher than that in the smoking control group [(1.65±0.63) μg/ml] and the non-smoking control group[(0.99±0.48)μg/ml], t=5.807, P<0.000 1; t=18.45, P<0.000 1. The serum S100A8/A9 levels in patients with COPD[GOLD Ⅰ(2.08±1.08) μg/ml, GOLDⅡ (2.58±1.06) μg/ml, GOLD Ⅲ (2.69±1.12) μg/ml, GOLDⅣ (2.95±1.10)μg/ml] were significantly higher than the non-smoking control group(0.99±0.48)μg/ml, t=6.616, P<0.000 1; t=14.56, P<0.000 1; t=17.10, P<0.000 1; t=18.09, P<0.000 1.The serum sRAGE level [(0.29±0.25)ng/ml] in COPD patients was significantly higher than that in the smoking control group[(0.60±0.24)ng/ml] and the non-smoking control group[(0.85±0.35)ng/ml], t=7.367, P<0.000 1; t=18.14, P<0.000 1. The serum sRAGE levels in patients with COPD[GOLD Ⅰ(0.46±0.40),GOLDⅡ (0.28±0.25),GOLD Ⅲ (0.29±0.25),GOLD Ⅳ (0.25±0.19)ng/ml] were significantly lower compared with non-smoking control group[(0.85±0.35)ng/ml], t=3.459, P=0.000 5; t=10.23, P<0.000 1; t=13.95, P<0.000 1; t=11.70, P<0.000 1. Serum S100A8/A9 levels were positively correlated with smoking amount and NEU% (r=0.458 5, P<0.000 1; r=0.228 3, P=0.001 1), negatively correlated with FEV1/FVC, the percentage of FEV1 in the predicted value, and sRAGE(r=-0.190 6, P=0.006 4; r=-0.186 3, P=0.007 8; r=-0.201 7, P=0.003 9). sRAGE levels were negatively correlated with NEU% (r=-0.155 9, P=0.026 4). In the ROC curve, the area under the curve of S100A8/A9, sRAGE and combined detection were 0.922[95%CI(0.897-0.947)], 0.926[95%CI(0.899-0.952)]and 0.966 [95%CI(0.950-0.983)], respectively.@*Conclusion@#S100A8/A9 and sRAGE are closely correlated with the degree of airflow constrains and the levels of serum inflammatory mediators, which are expected to be as potential biomarkers of COPD.

Expression and function of advanced glycosylation end product receptors and intracellular signal molecules in lung adenocarcinoma cells / 安徽医科大学学报

Objective To explore the expression of the receptor for advanced glycosylation end products(RAGE) and its intracellular signaling molecules DIAPH1 in lung adenocarcinoma A549 cells and the effect of RAGE ligands on cell migration and apoptosis. Methods The expressions of RAGE and DIAPH1 in lung adenocarcinoma A549 cells and human bronchial epithelial cells BEAS-2B were tested by qRT-PCR and Western blot. A549 cells was treated with 10,100 μg /ml RAGE ligands CML-AGE and 1,10,100 μg /ml S100B,and wound healing test was used to identify the effect of migration ability. A549 cells was treated with 25,50,100 μg /ml RAGE ligands CMLAGE, the gene expression of BCL-2 and BAX were tested by using qRT-PCR. Results The results of qRT-PCR and Western blot showed,compared with human bronchial epithelium cells BEAS-2B,the expression of RAGE and DIAPH1 were both significantly down-regulated in lung adenocarcinoma A549 cells (P < 0. 001). After treated with 10,100 μg /ml RAGE ligands CML-AGE and 1,10,100 μg /ml S100B ,both groups showed the ligands inhibit lung adenocarcinoma A549 cells migration in concentration-depend manners (P < 0. 01). After treated with 25, 50,100 μg /ml RAGE ligands CML-AGE,the expression of anti-apoptotic gene BCL-2 was down-regulated and proapoptotic gene BAX was upregulated in the experimental group in concentration-depend manners(P < 0. 05),the difference was significant. Conclusion The expression levels of RAGE and DIAPH1 in lung adenocarcinoma A549 cells are both significantly lower than human bronchial epithelium cells BEAS-2B. RAGE ligands can inhibit cells migration and promote cell apoptosis in lung adenocarcinoma A549 cells and may provide a new target for the therapy of lung adenocarcinoma cells.

Expression of the receptor of advanced glycation end products in gingival tissue endothelial cells from type 2 diabetic rats with chronic periodontitis / 口腔疾病防治

Objective @# To evaluate the expression of the receptor for advanced glycation end products (RAGE) in gingival tissue endothelial cells from type 2 diabetic rats with chronic periodontitis and to explore the role of RAGE in the pathogenesis of diabetes in cases with chronic periodontitis.@*Methods@#Sixty 7-week-old female Wistar diabetic obese rats were randomly divided into two groups. Periodontitis was induced in 30 rats by silk ligation, and the other 30 rats were used as the control group in which the periodontal tissues were not treated. One week after periodontal ligation and inoculation, the periodontitis and control group rats were randomly divided into two subgroups; the first subgroup was fed a high-fat diet, and the second group was fed a low-fat diet. Thus, 15 rats per group were included in the high-fat diet periodontitis (HF/P), low-fat diet periodontitis (LF/P), high-fat diet periodontal health (HF/C), and low-fat diet periodontal health (LF/C) groups. Glucose tolerance tests were performed weekly to measure the fasting insulin and blood glucose levels and the insulin resistance index to verify successful construction of the rat diabetes model. After successful modeling of chronic periodontitis, the rats were sacrificed at the 13th week after measurement of the serum necrosis factor-α (TNF-α), interleukin-6 (IL-6) and leptin levels. The tooth periodontal tissues were prepared and sectioned to observe histological changes. Immunofluorescence double staining was used to detect the density of RAGE-positive endothelial cells in the gingival tissues of the four groups.@* Results @#The serum fasting blood glucose and insulin levels and insulin resistance index were significantly higher in the HF/P and HF/C groups than in the LF/P and LF/C groups (P < 0.01). The serum TNF-α and IL-6 levels were significantly higher in the HF/P and LF/P groups than in the HF/C and LF/C groups (P < 0.01). The serum leptin levels were significantly higher in the HF/P group than in the other three groups. The density of RAGE-positive endothelial cells was significantly higher in the HF/P and HF/C groups than in the LF/P (P=0.001) and LF/C groups (P=0.040). The density of RAGE-positive endothelial cells in the HF/P group was higher than that in the HF/C group (P=0.027).@*Conclusion@#Endothelial cells in type 2 diabetic rats with periodontitis have increased gingival tissue RAGE and serum leptin levels.

Construction and identification of recombinant lentiviral plasmid of receptor for advanced glycation end products / 国际生物医学工程杂志

Objective To construct a recombinant lentiviral plasmid of receptor for advanced glycation end products (RAGE) and establish RAGE stable expressing hepatocellular carcinoma cell models in order to explore the pathogenesis of RAGE in the occurrence and development of hepatocellular carcinoma. Methods RAGE gene fragments were amplified by PCR and cloned into the lentiviral expression vector pCDH-CMV-MCS-EF1-Puro. Then the recombinant lentiviral plasmid and packaging plasmid were used to package lentivirus in HEK293T cells by calcium phosphate transfection. Lentivirus supernatant was collected to infect hepatoma cells HepG2 and Huh7. After that cells were screened by puromycin. Finally, RAGE expression was detected by real-time PCR and Western blot. Results RAGE gene fragment was successfully amplified and inserted into lentiviral expression vector. After packaging the lentivirus-infected liver cancer cells, real-time quantitative PCR and Western blot results showed that the mRNA (P<0.05) and protein expression of RAGE cells stably expressing RAGE were significantly higher than that of the control cells. Conclusions The RAGE overexpressing hepatocarcinoma cell line was successfully constructed by using lentiviral expression vector, which laid a good foundation for further study on the pathogenesis of RAGE.

The relationship of MEOX2 and neurovascular dysfunction in Alzheimer's disease model / 药学学报

Present study investigated the role of mesenchyme homeobox 2 (MEOX2) gene in neurovascular dysfunction in Alzheimer's disease (AD) model rats by bilateral intracerebroventricular injection of Aβ1-42. One week after surgery, Morris water maze, immunohistochemistry, biochemical detection, Western blot and real-time PCR were used to detect the indexes. The animal studies were conducted in accordance with the Regulations of Experimental Animal Administration issued by the State Committee of Science and Technology of the People's Republic of China. Compared to the Sham-operated rats, Aβ1-42-operated rats showed obviously cognitive dysfunction, accompanied by increased Aβ, glial fibrillary acidic protein (GFAP), allograft inflammatory factor 1 (AIF1), endothelial nitric oxide synthase (eNOS) and decreased neuron specific enolase (NSE), synaptophysin (SYN), CD34, vascular endothelial growth factor (VEGF) expressions of brain. Aβ1-42-operated rats also increased the endothelin (ET) level and decreased nitric oxide (NO) level in brain tissue. Moreover, MEOX2 expression was decreased correlated with low density lipoprotein receptor-related protein 1 (LRP-1) decreasing and receptor for advanced glycation end products (RAGE) increasing in brain tissues of AD model rats. We found the correlation between MEOX2 gene expression and neurovascular dysfunction, in addition, the decreased MEOX2 may involve in increasing the accumulation of Aβ in brain by relating to the decreased LRP-1 and increased RAGE which is located in blood-brain barrier (BBB) in senescence-accelerated mice.

High-mobility group box 1 protein (HMGB1) in maternal plasma affects Th17/Treg balance via receptor for advanced glycation end products( RAGE) -IL-6 pathway in preeclamptic pregnancies / 中华微生物学和免疫学杂志

Objective To analyze the relationships of high mobility group box 1 protein (HMGB1) with regulatory T cells (Treg), T helper 17 cells (Th17) and cytokine secrtion in peripheral blood of gravidas with preeclampsia(PE),and to investigate the mechanism of HMGB1 in regulating Th17/Treg ratio via receptor for advanced glycation end products (RAGE)-IL-6 pathway. Methods Forty gravi-das with mild(20 cases) and severe(20 cases) PE were recruited as experimental groups,20 heathy gravi-das in the third trimester of pregnancy were enrolled as control group. Concentrations of HMGB1,IL-6,IL-17 and TGF-β in peripheral blood of all subjects were determined by enzyme-linked immunosorbent assay (ELISA). Real-time quantitative PCR(RT-PCR) was used to detect the expression of RAGE at mRNA lev-el in peripheral blood mononuclear cells(PBMCs). The percentages of Treg and Th17 cells were determined by flow cytometry. RT-PCR was performed to analyze changes in the expression of RAGE,IL-6,Foxp3 and RORγt at mRNA level after the PBMCs isolated from 20 garvidas with PE were cultured in vitro and stimula-ted with recombinant human HMGB1 (rhHMGB1). Results The levels of HMGB1,IL-6,Th17 and IL-17 in peripheral blood of gravidas with PE were significantly higher than those in the normal pregnancy group. Moreover,HMGB1 level was positively correlated with IL-6 level and ratios of Th17/Treg and IL-17/TGF-β in preeclamptic pregancies. In vitro stimulation of PBMCs with rhHMGB1 significantly enhanced the expres-sion of RAGE,IL-6 and RORγt at mRNA level, but suppressed the expression of Foxp3 at mRNA level. Conclusion Enriched HMGB1 in plasma shifts the Th17/Treg balance towards Th17 dominance via the RAGE-IL-6 pathway, which exacerbates inflammation and participates in the onset of preeclampsia during pregnancy.

The Role of Advanced Glycation End Products in Diabetic Vascular Complications

In cases of chronic hyperglycemia, advanced glycation end-products (AGEs) are actively produced and accumulated in the circulating blood and various tissues. AGEs also accelerate the expression of receptors for AGEs, and they play an important role in the development of diabetic vascular complications through various mechanisms. Active interventions for glucose and related risk factors may help improve the clinical course of patients by reducing AGEs. This review summarizes recent updates on AGEs that have a significant impact on diabetic vascular complications.

S100A8 inhibits PDGF-induced proliferation of airway smooth muscle cells dependent on the receptor for advanced glycation end-products

BACKGROUND: Airway remodeling is a key feature of asthma, characterized by increased proliferation of airway smooth muscle cells (ASMCs). S100A8 is a calcium-binding protein with a potential to regulate cell proliferation. Here, the effect of exogenous S100A8 protein on the proliferation of ASMCs induced by platelet-derived growth factor (PDGF) and the underlying molecular mechanism was investigated. METHODS: Rat ASMCs were cultured with or without a neutralizing antibody to the receptor for advanced glycation end-products (RAGE), a potential receptor for S100A8 protein. Purified recombinant rat S100A8 protein was then added into the cultured cells, and the proliferation of ASMCs induced by PDGF was detected by colorimetric-based WST-8 assay and ampedance-based xCELLigence proliferation assay. The expression levels of RAGE in ASMCs were analyzed using western blotting assay. RESULTS: Results showed that exogenous S100A8 inhibited the PDGF-induced proliferation of rat ASMCs in a dose- dependent manner with the maximal effect at 1 µg/ml in vitro. Furthermore, when ASMCs was pre-treated with anti-RAGE neutralizing antibody, the inhibitory effect of S100A8 on PDGF-induced proliferation was significantly suppressed. In addition, neither the treatment with S100A8 or PDGF alone nor the pre-treatment with rS100A8 followed by PDGF stimulation affected the expression levels of RAGE. CONCLUSIONS: Our study demonstrated that S100A8 inhibits PDGF-induced ASMCs proliferation in a manner dependent on membrane receptor RAGE.

Impact of ethyl pyruvate on the cognitive function after splenectomy in aged rats / 临床麻醉学杂志

Objective To investigate the impact of ethyl pyruvate (EP) on cognitive function and the expression of high mobility group box 1 (HMGB1) and receptor for advanced glycation end products (RAGE) after splenectomy in aged rats.Methods Eighty-four male aged Sprague-Dawley rats, 18 months old, weighing 500-600 g, were randomly divided into 4 groups (n=21 each) by random number table method: control group (group C), surgery group (group S) ethyl pyruvate group (group E) and solution without EP group (group R).Morris water maze test was performed to evaluate cognitive function 5 days before surgery and 1, 3, 7 days after surgery.Group E was injected with EP 40 mg/kg intrapertoneally after splenectomy, group S and group C were injected with equivalent normal saline after splenectomy, group R was injected with equivalent solution without EP.Rats were killed after Morris water maze test, and the expression of HMGB1 and RAGE protein and mRNA in hippocampus were measured by Western blot and RT-PCR methods.Results Compared with group C, the escape latency and swimming distance were significantly prolonged in groups S, E and R 1 and 3 days after surgery, as well as the expression of HMGB1 and RAGE in hippocampus were significantly up-regulated (P＜0.05).Compared with group S, the escape latency and swimming distance were significantly decreased and the expression of HMGB1 and RAGE were down-regulated in group E 1 and 3 days after surgery (P＜0.05).Compared with the preoperative group, the escape latency and swimming distance were significantly prolonged in groups S, E and R 1 and 3 days after surgery (P＜0.05).Conclusion EP may improve cognitive function in aged rats by down regulating the expression of HMGB1 and RAGE in the hippocampus.

Influence of down-regulation of RAGE receptor on HMGB1 expression and the volume of transplanted tumor / 实用医学杂志

Objective To explore the down-regulation of advanced receptor for advanced glycation end products(RAGE)on expression of high mobility group protein B1(HMGB1)in glioma cells line and the volume change of transplanted tumor in nude mice. Methods HMGB1 expression in glioma LN229 cells line (divided into a control group and a study group) was observed by immunohistochemical assay and Western blot. The control group received normal saline,whereas the study group received RAGE receptor blocking agent FPS-ZM1. Expression of HMGB1 protein was detected by the same methods. The difference of the expression was examined by independent sample t test. 30 Nu/Nu nude mice were randomly divided into two groups;the above two kinds cell lines were injected into the same area of the left back of nude mice. Six weeks after injection ,the volume size was measured six times ,and the variance of repeated measurement data was used to analyze the difference of the volume change. Results HMGB1 protein was mainly expressed in the cytoplasm and nucleus. As compared with the control group,HMGB1 protein expression levels were decreased in the study group(P < 0.05),the growth rate of transplanted tumor in nude mice was significantly faster in the control group than in the study group ,the difference was statistically significant(P < 0.05). Conclusions The growth and invasion of HMGB1 protein may be involved in glioma by RAGE receptor. RAGE receptor blocker FPS-ZM1 can significantly reduce the expression of HMGB1 protein and inhibit the growth of transplanted tumor volume. It is expected to be used for the research on glioma cell apoptosis.

Intrafollicular Soluble RAGE Benefits Embryo Development and Predicts Clinical Pregnancy in Infertile Patients of Advanced Maternal Age Undergoing In Vitro Fertilization / 华中科技大学学报（医学）（英德文版）

Soluble receptor for advanced glycation end products (sRAGE) can decoy the toxic AGEs and is considered to be a protective factor.This study aimed to evaluate the correlation between intrafollicular sRAGE levels and clinical outcomes in infertile women of young or advanced maternal age (AMA) undergoing in vitro fertilization (IVF).A total of 62 young women and 62 AMA women who would undergo IVF were included in this prospective study.The intrafollicular sRAGE concentration was measured to determine its association with the number of retrieved oocytes,fertilized oocytes,high-quality embryos or achievement of clinical pregnancy in young and AMA women,respectively.Besides,correlations between sRAGE and age or follicle-stimulating hormone (FSH) were examined.We found that the intrafollicular sRAGE levels were higher in young patients than those in AMA patients,suggesting that the sRAGE levels were inversely correlated with age.In young patients,sRAGE showed no correlation with the number of retrieved oocytes,fertilized oocytes,high-quality embryos or achievement of clinical pregnancy.But it was found that AMA patients with more retrieved oocytes,fertilized oocytes and high-quality embryos demonstrated higher sRAGE levels,which were a prognostic factor for getting clinical pregnancy independent of age or FSH level.In conclusion,the sRAGE levels decrease with age.Elevated intrafollicular sRAGE levels indicate good follicular growth,fertilization and embryonic development,and successful clinical pregnancy in AMA women,while in young women,the role of sRAGE may not be so predominant.