Amyloid precursor-like protein 2 C-terminal fragments upregulate S100A9 gene and protein expression in BV2 cells

The murine microglial cell line BV2 has neuroprotective effects, but is toxic to neurons by secret-ing inlfammatory cytokines, and is an important target in the treatment of nerve inlfammation and neurodegenerative diseases. In the present study, we observed the effects of transfecting three amyloid precursor-like protein 2 （APLP2） C-terminal fragments （CTFs; C57, C50 and C31） in the pEGFP-N1 vector on S100A9 expression in BV2 cells. Reverse transcription-PCR, western blot assay and immunocytochemistry revealed that S100A9 protein and mRNA expression was greater in BV2 cells after CTF transfection than after mock transfection with an empty vector. Furthermore, transfection of full-length APLP2-751 resulted in low levels of S100A9 protein ex-pression. Our results show that APLP2-CTFs upregulate S100A9 protein and mRNA expression in BV2 cells, and identify a novel pathway involved in neuronal injury and apoptosis, and repair and protection in Alzheimer’s disease.

Effect of salvia miltiorrhiza and ligustrazine hydrochloride injection combined with hydroxyethyl starch injection on serum BNP, Hcy, MMP-2, S100B protein and hemorheology in patients with acute cerebral watershed infarction

Objective:To study the effect of salvia miltiorrhiza and ligustrazine hydrochloride injection combined with hydroxyethyl starch injection on serum BNP, Hcy, MMP-2, S100B protein and hemorheology in patients with acute cerebral watershed infarction.Methods:A total of 90 patientswith acute cerebral watershed infarction in our hospital from August 2014 to December 2016 were enrolled in this study. The subjects were divided into the control group (n=45) and the treatment group (n=45) randomly. The control group was treated with hydroxyethyl starch injection, the treatment group was treated withsalvia miltiorrhiza and ligustrazine hydrochloride injection combined with hydroxyethyl starch injection, and both the two groups were treated for 2 weeks. The serum BNP, Hcy, MMP-2, S100B protein and hemorheology of the two groups before and after treatments were compared.Results:There were no significantly differences of the serum BNP, Hcy, MMP-2, S100B protein and hemorheology of the two groups before treatment. The serum BNP, Hcy, MMP-2, S100B proteinlevels of the two groups after treatment were significantly lower than before treatment, and that of the treatment group after treatment were significantly lower than the control group. The PV, Lr, Mr, Hr and RE of the two groups after treatment were significantly lower than before treatment, and that of the treatment group after treatment were significantly lower than the control group.Conclusion:Salvia miltiorrhiza and ligustrazine hydrochloride injection combined with hydroxyethyl starch injectioncan significantlyimprovetheneurological function and hemorheology, reduce inflammation of the patients with acute cerebral watershed infarction, and it was worthy clinical application.

EudragitS-100对蛋白折叠的促进作用

目的:以重组人角化细胞生长因子(recombinant human keratinocyte growth factor-2,rhKGF-2)为模型,研究一种对pH较为敏感的多聚化合物聚丙烯酸树脂EudragitS-100对蛋白折叠的促进作用及其作用机制。方法:直接将变性蛋白加入到含有不同浓度Eudragit的蛋白复性缓冲液中,采用MTT法、荧光分光光度法、圆二色光谱法以及高效液相色谱法来比较分析不同浓度EudragitS-100对变性rhKGF-2的复性促进作用。结果:在Eudragit S-100作用下,rhKGF-2的复性产率比普通稀释复性法显著增高且最高达到71%。研究表明Eudragit S-100的促进蛋白折叠的作用是基于Eudragit S-100与rh-KGF-2发生了特异性的结合反应。另外,本研究还发现蛋白复性缓冲液中尿素的浓度对蛋白的复性也存在较大影响。结论:Eudragit S-100能显著提高以rhKGF-2为代表的蛋白的正确折叠和复性收率。

S100 calcium-binding protein A9 promotes skin regeneration through toll-like receptor 4 during tissue expansion

Background:In plastic surgery,tissue expansion is widely used for repairing skin defects.However,low expansion efficiency and skin rupture caused by thin,expanded skin remain significant challenges in promoting skin regeneration during expansion.S100 calcium-binding protein A9(S100A9)is essential in promoting wound healing;however,its effects on skin regeneration during tissue expansion remain unclear.The aim of the present study was to explore the role of S100A9 in skin regeneration,particularly collagen production to investigate its importance in skin regeneration during tissue expansion.Methods:The expression and distribution of S100A9 and its receptors-toll-like receptor 4(TLR-4)and receptor for advanced glycation end products were studied in expanded skin.These character-istics were investigated in skin samples of rats and patients.Moreover,the expression of S100A9 was investigated in stretched keratinocytes in vitro.The effects of S100A9 on the proliferation and migration of skin fibroblasts were also observed.TAK-242 was used to inhibit the binding of S100A9 to TLR-4;the levels of collagen I(COL I),transforming growth factor beta(TGF-β),TLR-4 and phospho-extracellular signal-related kinase 1/2(p-ERK1/2)in fibroblasts were determined.Furthermore,fibroblasts were co-cultured with stretched S100A9-knockout keratinocytes by siRNA transfection and the levels of COL I,TGF-β,TLR-4 and p-ERK1/2 in fibroblasts were investigated.Additionally,the area of expanded skin,thickness of the dermis,and synthesis of COL I,TGF-β,TLR-4 and p-ERK1/2 were analysed to determine the effects of S100A9 on expanded skin.Results:Increased expression of S100A9 and TLR-4 was associated with decreased extracellular matrix(ECM)in the expanded dermis.Furthermore,S100A9 facilitated the proliferation and migration of human skin fibroblasts as well as the expression of COL I and TGF-βin fibroblasts via the TLR-4/ERK1/2 pathway.We found that mechanical stretch-induced S100A9 expression and secretion of keratinocytes stimulated COL I,TGF-β,TLR-4 and p-ERK1/2 expression in skin fibroblasts.Recombined S100A9 protein aided expanded skin regeneration and rescued dermal thinning in rats in vivo as well as increasing ECM deposition during expansion.Conclusions:These findings demonstrate that mechanical stretch promoted expanded skin regeneration by upregulating S100A9 expression.Our study laid the foundation for clinically improving tissue expansion using S100A9.

Glial fibrillary acidic protein levels are associated with global histone H4 acetylation after spinal cord injury in rats

Emerging evidence has suggested global histone H4 acetylation status plays an important role in neural plasticity. For instance, the imbalance of this epigenetic marker has been hypothesized as a key factor for the development and progression of several neurological diseases. Likewise, astrocytic reactivity-a wellknown process that markedly influences the tissue remodeling after a central nervous system injury-is crucial for tissue remodeling after spinal cord injury（SCI）. However, the linkage between the above-mentioned mechanisms after SCI remains poorly understood. We sought to investigate the relation between both glial fibrillary acidic protein（GFAP） and S100 calcium-binding protein B（S100B）（astrocytic reactivity classical markers） and global histone H4 acetylation levels. Sixty-one male Wistar rats（aged ~3 months） were divided into the following groups： sham; 6 hours post-SCI; 24 hours post-SCI; 48 hours post-SCI; 72 hours post-SCI; and 7 days post-SCI. The results suggested that GFAP, but not S100B was associated with global histone H4 acetylation levels. Moreover, global histone H4 acetylation levels exhibited a complex pattern after SCI, encompassing at least three clearly defined phases（first phase： no changes in the 6, 24 and 48 hours post-SCI groups; second phase： increased levels in the 72 hours post-SCI group; and a third phase： return to levels similar to control in the 7 days post-SCI group）. Overall, these findings suggest global H4 acetylation levels exhibit distinct patterns of expression during the first week post-SCI, which may be associated with GFAP levels in the perilesional tissue. Current data encourage studies using H4 acetylation as a possible biomarker for tissue remodeling after spinal cord injury.

Clinical scenarios for the use of S100β as a marker of hepatic encephalopathy

AIM: To evaluate the association between serum concentrations of S100β in patients with cirrhosis and the presence of low grade hepatic encephalopathy (HE).METHODS: This was a cross-sectional study. The population was categorized into four groups healthy subjects, cirrhosis without HE, cirrhosis with covert hepatic encephalopathy (CHE) and cirrhosis with overt HE. Kruskal-Wallis, Mann Whitney’s U with Bonferroni adjustment Spearman correlations and area under the ROC were used as appropriate.RESULTS: A total of 61 subjects were included, 46 cirrhotic patients and 15 healthy volunteers. S100β values were different among all groups, and differences remained significant between groups 1 and 2 (P < 0.001), and also between groups 2 and 3 (P = 0.016), but not between groups 3 and 4. In cirrhotic patients with HE S100β was higher than in patients without HE [0.18 (0.14-0.28) ng/mL vs 0.11 (0.06-0.14) ng/mL, P < 0.001]. There was a close correlation between serum concentrations of S100β and psychometric hepatic encephalopathy score in patients with cirrhosis without HE compared to the patients with cirrhosis with CHE (r = -0.413, P = 0.019). ROC curve analysis yielded > 0.13 ng/mL as the best cutoff value of S100β for the diagnosis of HE (sensitivity 83.3%, specificity 63.6%).CONCLUSION: Serum concentrations of S100β are higher in patients with cirrhosis than in healthy volunteers, and are further increased in the presence of hepatic encephalopathy. The results suggest that serum biomarkers such as S100β could help in the correct characterization of incipient stages of HE.

S100A8 promotes epithelial-mesenchymal transition and metastasis under TGF-β/USF2 axis in colorectal cancer

Background:The transforming growth factor-β(TGF-β)pathway plays a pivotal role in inducing epithelial-mesenchymal transition(EMT),which is a key step in cancer invasion and metastasis.However,the regulatory mechanism of TGF-βin inducing EMT in colorectal cancer(CRC)has not been fully elucidated.In previous studies,it was found that S100A8 may regulate EMT.This study aimed to clarify the role of S100A8 in TGF-β-induced EMT and explore the underlying mechanism in CRC.Methods:S100A8 and upstream transcription factor 2(USF2)expression was detected by immunohistochemistry in 412 CRC tissues.Kaplan-Meier survival analysis was performed.In vitro,Western blot,and migration and invasion assays were performed to investigate the effects of S100A8 and USF2 on TGF-β-induced EMT.Mouse metastasis models were used to determine in vivo metastasis ability.Luciferase reporter and chromatin immunoprecipitation assay were used to explore the role of USF2 on S100A8 transcription.Results:During TGF-β-induced EMT in CRC cells,S100A8 and the transcription factor USF2 were upregulated.S100A8 promoted cell migration and invasion and EMT.USF2 transcriptionally regulated S100A8 expression by directly binding to its promoter region.Furthermore,TGF-βenhanced the USF2/S100A8 signaling axis of CRC cells whereas extracellular S100A8 inhibited the USF2/S100A8 axis of CRC cells.S100A8 expression in tumor cells was associated with poor overall survival in CRC.USF2 expression was positively related to S100A8 expression in tumor cells but negatively related to S100A8-positive stromal cells.Conclusions:TGF-βwas found to promote EMT and metastasis through the USF2/S100A8 axis in CRC while extracellular S100A8 suppressed the USF2/S100A8 axis.USF2 was identified as an important switch on the intracellular and extracellular S100A8 feedback loop.

儿童手术应激升高血清髓样相关蛋白8/14的表达

髓样相关蛋白8（myeloid-related protein,MRP 8,又称S100A8或calgranulin A）和髓样相关蛋白14（MRP 14,又称S100A9或calgranulin B）是两种Ca^2＋结合蛋白,属于Ca^2＋结合蛋白S100家族,并且MRP8和MRP14通常以MRP8/14复合物的形式存在[1]。其主要在单核细胞和巨噬细胞等髓系来源的细胞中表达,比如中性粒细胞和单核细胞.

Effect of Electroacupuncture Preconditioning on Serum S100 β and NSE in Patients undergoing Craniocerebral Tumor Resection

Objective：To investigate the effect of electroacupuncture preconditioning on the serum level of S100 calcium-binding protein beta（S100β）and neuron-specific enolase（NSE）in patients undergoing craniocerebral tumor operation.Methods：A total of 32 patients,who would go through craniocerebral tumor resection under general anesthesia,were randomly assigned to two groups,16 in each group.Patients in the electroacupuncture（EA）group received electroacupuncture on Fengfu acupoint（Du16）and Fengchi acupoint （GB20）for 30 min,2 h before operation.The stimulus is 1-4 mA with a density wave frequency of 2/15 Hz. Patients in the control group received no pretreatment.Anesthesia was maintained with remifentanil at the dose of 4-8 mg/kg per hour,pumped intravenous drip of vecuronium at 1.0-2.0μg/kg each hour,and discontinuous intravenous dripped with vecuronium bromide at 0.5-1 mg.The serum levels of S100βand NSE were measured with ELISA before operation,before skin incision,after tumor removal,at the end of operation,and at 24 h after operation.Results：The serum level of S100βand NSE did not change before skin incision.The serum level of NSE increased significantly and the level of S100βincreased insignificantly after the tumor resection. The serum levels of S100βand NSE in the EA group and the control group were 1.16±0.28μg/L vs 1.47±0.33μg/L,24.7±13.3μg/L vs 31.4±14.1μg/L at the end of the operation,respectively.Twenty-four h after operation,the correspondence indices were 1.18±0.31μg/L vs 1.55±0.26μg/L,and 25.5±12.4μg/L vs 32.4±11.7μg/L.The two indices at these two time points were significantly increased than those before operation, respectively（P〈0.05）.At the end of the operation and 24 h post-operation,the serum levels of S100βand NSE in the EA group were significantly lower than those in the control group（P〈0.05）.Conclusion：Electroacupuncture Fengchi and Fengfu for 30 min before craniocerbral tumor operation could decrease the serum level of S100βand NSE,thus may have potential protective effect on brain damage,which needs to befurther studied.

S100钙结合蛋白B在骨性关节炎软骨损伤修复中的作用及机制研究

目的探讨S100钙结合蛋白B(S100B)在骨性关节炎(osteoarthritis,OA)软骨损伤修复中的作用及机制。方法取20只新西兰兔随机分为对照组和模型组,每组10只。模型组兔右膝关节制动法制备软骨损伤模型,对照组不作任何处理。4周后采用ELISA法检测关节液IL-1β、TNF-α水平,实时荧光定量PCR(real-time fluorescence quantitative PCR,qRT-PCR)和Western blot检测软骨组织S100B、FGF-2、FGF受体1(FGF receptor 1,FGFR1)基因及蛋白表达。分离培养人滑膜成纤维细胞(synovial fibroblasts,SF),观察过表达、干扰S100B以及拮抗FGFR1对细胞IL-1β和TNF-α水平(ELISA法)以及FGF-2和FGFR1基因(qRT-PCR检测)和蛋白(Western blot检测)表达的影响。结果 ELISA检测示模型组兔关节液中IL-1β和TNF-α表达水平均明显高于对照组(P<0.05);qRT-PCR和Western blot检测示,模型组兔软骨组织S100B、FGF-2、FGFR1 mRNA和蛋白表达量均显著高于对照组(P<0.05)。过表达和干扰S100能够分别显著升高和降低脂多糖(lipopolysaccharides,LPS)诱导的IL-1β和TNF-α水平及FGF-2和FGFR1 mRNA和蛋白表达,差异均有统计学意义(P<0.05)。而拮抗FGFR1能够显著降低LPS诱导的IL-1β和TNF-α水平及FGF-2和FGFR1 mRNA和蛋白表达,差异均有统计学意义(P<0.05)。结论 S100B能够调节SF炎性反应并可能影响OA软骨损伤修复,其机制可能与激活FGF-2/FGFR1信号通路有关。