Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia

Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease.

Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure

BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF.

肉苁蓉苷A通过JNK/MAPK通路抑制破骨细胞活性

背景:研究证实肉苁蓉苷A具有抗炎、抗氧化和抗骨质疏松的作用,但其对破骨细胞分化和功能的影响及潜在的机制尚缺少研究。目的:探讨肉苁蓉苷A对核因子κB受体活化因子配体诱导的体外破骨细胞分化和骨吸收功能的影响及作用机制。方法:提取与培养4-6周龄C57BL/6小鼠股骨和胫骨中的骨髓巨噬细胞,采用CCK-8毒性实验检验不同浓度的肉苁蓉苷A(5,10,20,40,80,160μmol/L)对骨髓巨噬细胞的毒性,抗酒石酸酸性磷酸酶染色观察不同浓度的肉苁蓉苷A干预破骨细胞的分化情况,确定药物的有效干预浓度。将实验分为阳性对照组、肉苁蓉苷A低、中、高剂量组(40,80,160μmol/L),细胞贴壁后各组均加入50 ng/mL的核因子κB受体活化因子配体诱导破骨细胞分化,肉苁蓉苷A低、中、高剂量组分别加入相应剂量的肉苁蓉苷A进行干预。采用肌动蛋白环鬼笔环肽染色和DAPI染色检测肉苁蓉苷A对破骨细胞形成的影响;骨磨片甲苯胺蓝染色观察肉苁蓉苷A对破骨细胞骨吸收功能的影响;Western blot检测JNK/MAPK通路上下游蛋白的表达情况;RT-qPCR检测抗酒石酸酸性磷酸酶、DC-STAMP、Nfatc-1、Ctsk和c-Fos等破骨细胞分化和骨吸收功能相关基因的表达情况。结果与结论:①抗酒石酸酸性磷酸酶染色、肌动蛋白环染色和骨陷窝甲苯胺蓝染色结果表明,与阳性对照组相比,肉苁蓉苷A对核因子κB受体活化因子配体诱导的体外破骨细胞的分化和骨吸收功能具有呈剂量依赖性的显著抑制作用;②RT-qPCR结果表明,与阳性对照组相比,肉苁蓉苷A高剂量组和低剂量组的抗酒石酸酸性磷酸酶、DC-STAMP、Nfatc-1、Ctsk和c-Fos等的mRNA表达量均显著降低,且肉苁蓉苷A高剂量组的降低效果更加显著;③Western blot结果显示,高剂量肉苁蓉苷A干预10,20,30和60 min时显著抑制p-JNK蛋白的表达;与阳性对照组相比,肉苁蓉苷A低、中、高剂量组显著抑制Nfatc1和c-Fos蛋白的表达,且呈剂量依赖性;④结果说明,肉苁蓉苷A能够通过降低p-JNK蛋白水平,抑制MAPK通路的激活和破骨细胞关键基因的表达,进而抑制破骨细胞的形成和骨吸收功能。

Monocyte and macrophage function in respiratory viral infections

Pulmonary macrophages,such as tissue-resident alveolar and interstitial macrophages and recruited monocyte-derived macrophages,are the major macrophages present in the lungs during homeostasis and diseased conditions.While tissue-resident macrophages act as sentinels of the alveolar space and play an important role in maintaining homeostasis and immune regulation,recruited macrophages accumulate in the respiratory tract after acute viral infections.Despite sharing similar anatomical niches,these macrophages are distinct in terms of their origins,surface marker expression,and transcriptional profiles,which impart macrophages with distinguished characteristics in physi-ological and pathophysiological conditions.In this review,we summarize the current view on these macrophage populations,their shared functions,and what makes them distinct from each other in the context of homeostasis andrespiratoryviral infections.

Monocyte to high-density lipoprotein cholesterol ratio as a predictor of the activity of thyroid-associated ophthalmopathy

AIM:To evaluate the relationship between monocyte to high-density lipoprotein cholesterol ratio(MHR)and the disease activity of thyroid-associated ophthalmopathy(TAO).METHODS:A total of 87 patients were classified into two groups based on clinical activity score(CAS)scoring criteria:high CAS group(n=62,the CAS score was≥3);low CAS group(n=25,the CAS score was<3).In addition,a group of healthy people(n=114)were included to compared the MHR.Proptosis,MHR,average signal intensity ratio(SIR),average lacrimal gland(LG)-SIR,average extraocular muscles(EOM)area from 87 patients with TAO were calculated in magnetic resonance imaging(MRI),and compared between these two groups.Correlation testing was utilized to evaluate the association of parameters among the clinical variables.RESULTS:Patients in high CAS group had a higher proptosis(P=0.041)and MHR(P=0.048).Compared to the healthy group,the MHR in the TAO group was higher(P=0.001).Correlation testing declared that CAS score was strongly associated with proptosis and average SIR,and MHR was positively associated with CAS score,average SIR,and average LG-SIR.The area under the receiver operating characteristic curve(AUC)of MHR was 0.6755.CONCLUSION:MHR,a novel inflammatory biomarker,has a significant association with CAS score and MRI imaging(average SIR and LG-SIR)and it can be a new promising predictor during the active phase of TAO.

Effect of NF-κB and p38 MAPK in activated monocytes/macrophages on pro-inflammatory cytokines of rats with acute pancreatitis

AIM: Proinfiammatory cytokines TNF-α and IL-6 play a main role in acute pancreatitis (AP). Cytokine biosynthesis runs through two major signaling pathways at the level of proteins: nuclear transcription factor-κB (NF-κB) and p38 mitogen-activated protein kinase (p38 MAPK). The aim of the study was to investigate the effect of NF-κB and p38 MAPK in activated monocytes/macrophages on cytokines of rats with acute pancreastitis.METHODS: Taurocholate (3 % and 5 %) at doses of 1 mL/kg was administered into the biliopancreatic duct of male Sprague-Dawley (SD) rats to reduce acute edematous pancreariris (AEP) and acute necrotizing pancreatitis (ANP).Pancreatic tissues were prepared immediately after death.At this point, blood was obtained for determination of serum amylase and pro-inflammatory TNF-α and IL-6. Activated monocytes/macrophages were captured from blood and so were ascites. NF-κB and p38 MAPK in activated monocytes/macrophages were measured by immunohistochemistry method. Pancreatic tissue samples were prepared for routine light microscopy, using hematoxylin and eosin (HE) staining.RESULTS: The serum levels of amylase were 3 056.00±1 232.35 IU/L and 4 865.12±890.34 IU/L at 3 and 6 hours in ANP group, which were significantly higher than those (3 056.00±1 232.35 TU/L and 3 187.17±821.16 IU/L) (P<0.05,respectively) in AEP group. In ascites the levels were 3.32±1.01 g and 3.76±1.12 g at 3 and 6 hours in ANP group,which were significantly higher than those (1.43±1.02 g and 2.56±1.21 g) (P<0.05, respectively) in AEP group. The serum levels of TNF-α were 54.27±23.48 pg/ml and 67.83±22.02 pg/ml in AEP group and 64.28±20.79 pg/ml and 106.59±43.71 pg/ml in ANP group, and the serum levels of IL-6 were 428.12±140.30 pg/ml and 420.13±139.40 pg/ml in AEP group and 1 600.32±309.78 pg/ml and 2 203.76±640.85 pg/ml in ANP group, which were far significantly higher than those in sham group (P<0.001, respectively). The serum level of TNF-α 6 hours after establishment of the studied model and that of IL-6 at 3 and 6 hours in ANP group were significantly higher than those in AEP (P<0.05, P<0.001, P<0.05). In ANP group, the levels of serum TNF-α and IL-6 6 hours after establishment of the studied model were significantly higher than those 3 hours after establishment of studied model (P<0.05, P<0.05, respectively). Three and 6 hours after establishment of the model, typical pathological changes of AEP and ANP were found, such as large numbers of inflammatory cells, edema, hemorrhage, necrosis, large amount of ascites. In AEP, NF-κB and p38 MAPK in activated monocytes/macrophages were moderately found at 3 and 6 hours after introduction of the model. However, in ANP,the expression of NF-κB and p38 MAPK in activated monocytes/macrophages was upregulated evidently at 3 and 6 hours after introduction of the model, reaching their highest levels at 6 hours after introduction of the model, which were consistent with the levels of TNF-α and IL-6.CONCLUSION: Cytokine TNF-α and IL-6 play a main rolein acute pancreatitis, expression of NF-κB and p38 MAPK in activated monocytes/macrophages might play a major role in cytokine transcription and biosynthesis.

Role of lymphocyte-to-monocyte ratio as a predictive marker for diabetic coronary artery disease: A cross-sectional study

BACKGROUND The lymphocyte to monocyte ratio(LMR)is considered a marker of systemic inflammation in cardiovascular disease and acts as predictor of mortality in coronary artery disease.AIM To investigate the predictive role of LMR in diabetic coronary artery disease patients.METHODS This cross-sectional study was conducted at tertiary care super-specialty hospital at New Delhi,India.A total of 200 angiography-proven coronary artery disease(CAD)patients were enrolled and grouped into two categories:Group I[CAD patients with type 2 diabetes mellitus(T2DM)and glycated hemoglobin(HbA1c)levels≥6.5%],and Group II(CAD patients without T2DM and HbA1c levels<6.5%).Serum lipoproteins,HbA1c,and complete blood count of enrolled patients were analyzed using fully automatic analyzers.RESULTS The logistic regression analysis showed an odds ratio of 1.48(95%CI:1.28-1.72,P<0.05)for diabetic coronary artery disease patients(Group I)in unadjusted model.After adjusting for age,gender,diet,smoking,and hypertension history,the odds ratio increased to 1.49(95%CI:1.29-1.74,P<0.01)in close association with LMR.Further adjustment for high cholesterol and triglycerides yielded the same odds ratio of 1.49(95%CI:1.27-1.75,P<0.01).Receiver operating characteristic curve analysis revealed 74%sensitivity,64%specificity,and 0.74 area under the curve(95%CI:0.67-0.80,P<0.001),suggesting moderate predictive accuracy for diabetic CAD patients.CONCLUSION LMR showed positive association with diabetic coronary artery disease,with moderate predictive accuracy.These findings have implications for improving CAD management in diabetics,necessitating further research and targeted interventions.

长链非编码RNA通过p38MAPK信号通路直接或间接影响骨质疏松症

背景:近年来大量的研究发现长链非编码RNA参与骨质疏松症的发生和发展。p38MAPK信号通路参与骨髓间充质干细胞、成骨细胞以及破骨细胞的分化等过程而参与骨质疏松症的发展,而长链非编码RNA可通过影响p38MAPK信号通路,直接或间接参与骨质疏松症的发生及发展过程。目的:综述长链非编码RNA通过p38MAPK信号通路,直接或间接影响骨质疏松症的进展,为长链非编码RNA在骨质疏松症中预防和治疗提供一个新思路。方法:检索PubMed、中国知网和万方数据库的相关文献,以“长链非编码RNA,骨质疏松,间充质干细胞,成骨细胞,破骨细胞,p38信号通路”为中文检索词,以“long non-coding RNA,osteoporosis,mesenchymal stem cells,osteoblasts,osteoclast,p38 signaling pathway”为英文检索词,排除陈旧、重复以及可信度低的观点,将检索到的文献进行归纳、总结和分析,选取76篇具有代表性的文章。结果与结论:(1)长链非编码RNA通过多种途径参与骨质疏松症的防治,包括促进骨髓间充质干细胞的成骨分化、促进成骨细胞分化和成骨细胞分泌活性、抑制破骨细胞增殖和对骨的吸收作用,以及调节成骨相关细胞通路的激活或抑制,激活p38MAPK信号通路延缓骨质疏松症进展,抑制该信号通路抑制破骨细胞的吸收作用,从而影响骨质疏松的发生和发展。(2)相应长链非编码RNA的过表达或低表达会通过p38MAPK信号通路来影响成骨细胞和破骨细胞的增殖或分化,调节骨重塑过程,进而影响骨质疏松症的发生和发展。大量的基础研究结果显示,长链非编码RNA和p38MAPK信号通路或许可以成为骨质疏松症治疗中的潜在应用和临床转化价值;且相应的长链非编码RNA过表达或低表达慢病毒、转染质粒,相应的p38MAPK信号通路抑制剂等在体外细胞实验及动物模型中都被证实有靶向调控作用。(3)因此,通过靶向调控长链非编码RNA和p38MAPK信号通路来调节骨髓间充质干细胞的分化和功能,或通过长链非编码RNA和p38MAPK信号通路来抑制破骨细胞的增殖分化,或许能提供一种创新的治疗策略,可以延缓骨质疏松症的进展。

Analysis of the Peripheral Blood Helper T-Cell 17- Cell Level and Monocyte/Lymphocyte Ratio for Colorectal Cancer Prognosis Prediction

Objective: To investigate the value of peripheral blood helper T cell 17 cell level and monocyte/lymphocyte ratio to predict the prognosis of colorectal cancer patients. Methods: 74 colorectal cancer patients who attended Hospital 960 from January 2021 to January 2022 were retrospectively analyzed. Clinical data of the patients were collected, including gender, age, and histologic type. Immunohistochemical indexes such as Th17 cell level and monocyte/ lymphocyte ratio in the peripheral blood of patients were also collected. The prognosis of patients after treatment, as well as peripheral blood Th17 and MLR levels, were observed and analyzed. Results: After follow-up after treatment, in the final 74 patients, the prognosis was good in 32 patients, accounting for 43.24%, and the prognosis was bad in 42 patients, accounting for 56.76%. There were no significant differences between the average age and tumor diameters of the good prognosis and poor prognosis groups (P > 0.05). However, the TNM staging, intervention taken, differentiation degree, presence of distant metastasis, presence of lymph node metastasis, Th17 level, and MLR level are significantly different between the two groups (P < 0.05). Conclusion: Peripheral blood Th17 and MLR have predictive value for the prognosis of colorectal cancer patients, and high levels of peripheral blood Th17 and MLR imply poor prognosis. The detection of peripheral blood Th17 and MLR levels is simple and convenient and can be used as indicators to provide a reference for the prognostic assessment of colorectal cancer patients.

Culture of Porcine Peripheral Blood Monocyte-derived Dendritic Cells in vitro

[Objective] This study aimed to establish an in vitro culture model for porcine peripheral blood monocyte-derived dendritic cells （MoDCs）. [Method] Fresh peripheral blood mononuclear cells （PBMCs） were separated from pig, and precursor dendritic cells were obtained by adherence method. The dendritic cells were treated by recombinant porcine granulocyte-monocyte colony stimulating factor （rpGM-CSF） and recombinant porcine interleukin-4 （rplL-4） together, and lipopolysaccharide （LPS） respectively. The cells in different time periods were collected. The morphology of the collected cells was observed by scanning electron microscopy; the expression of surface molecules and phagocytic ability to FITC-dextran were detected by flow cy- tometry; and the stimulating ability for allogeneic T cells was detected by mixed lymphocyte reaction. [Result] The DCs suffering maturation induction in vitro showed typical dendritic morphology; compared with those of DCs untreated by LPS, the cell surface expression of CDla, CD80, CD86, SLAII and CD172a of DCs treated by LPS was significantly increased, the phagocytic ability was reduced slightly, and the stimulating ability for allogeneic T cells was enhanced to some extent. [Conclusion] An in vitro culture method was successfully established for porcine MoDCs in this study, laying a foundation for further study on the role of porcine MoDCs in immunoregulation and anti-virus infection.

Arsenic trioxide inhibites transgenic tumor necrosis factor-α promoter activity in vascular smooth muscle cells and THP-1 monocytes in vitro

Aim This study was to evaluate the effect of arsenic trioxide （As2O3） on the transgenic TNF-α promoter activity in cultured vascular smooth muscle cells （VSMCs） and THP-1 monocytes. Methods Human TNF-α promoter was constructed by reporter gene system and was transiently transfected into VSMCs and THP-1 in vitro. The promoter activity was tested by luciferase activity with or without LPS and Ang Ⅱ stimulation, before and after different dosage of As2O3 treatment. Results 1. TNF-α promoter effectively expressed in VSMCs and THP-1 compared with CMV promoter （58.3% and 80.9%, respectively）. Both LPS and Ang Ⅱ significantly up-regulated TNF-α promoter activity （P〈0.05）. 2. As2O3 significantly inhibited, both intact and LPS/Ang Ⅱ stimulated promoter activity, in a dose dependent manner （P〈0.05）, and in both cell type. Conclusion These results manifested that, the inhibition effect of As2O3 on the activity of human TNF-α promoter indicated its potential inhibition on pro-inflammatory cytokine genes expression at transcriptional level and its potential anti-inflammatory property in the cardiovascular system.

Effect of HSV-2 Infected Monocytes on the Production of TNF-a and IL-6

Objective: In order to detect the role of monocytes inHSV-2 infection, we studied the effect of herpes sim-plex Virus-2 infection on the production of tumor ne-crosis factor (TNF-σ), interleukin-6 (IL-6) secretedby monocytes. Methods: Monocytes were infected by HSV-2 (333Strain). Culture supernatants were collected at 1, 3,5, 7 days post-infection. The levels of TNF-α, IL-6were measured by enzyme-linked immunosorbent as-say (ELISA). Results: The levels of TNF-α secretion by mono-cytes significantly decreased on first day post-infection. The levels of IL-6 significantly decreasedon first and third days post-infection, and then gradu-ally increased to the control on seventh day post-infection. Conclusions: TNF-α and IL-6 production by mono-cytes was inhibited during HSV-2 infection. The pro-duction of cytokines may play an important role inherpes simplex viurs-2 pathogenicity and immunity.

Effect of Herpes Simplex Virus-2 Infection in Vitro on the Expression of HLA Class II Antigen of Monocytes

Objectives: In order to investigate the role of mono-cytes and human leukocyte antigen (HLA) class II an-tigen in herpes simplex virus-2 (HSV-2) infection, westudied the effect of HSV-2 infection in vitro on theexpression of HLA class II antigen on monocytes.Methods: Monocytes were infected with HSV-2(Strain 333). Culture cells were collected 1, 3, 5 and 7days after infection. The levels of expression of HLAclass II antigen were measured by using alkaline phos-phatase antialkaline phosphatase method (APAAP).Results: The levels of the expression of HLA class IIantigen on monocytes significantly decreased on thefirst day of post-infection, and then gradually returnedto levels found in the controls by the 7th day post-infection.Conclusion: HLA class II antigen expression onmonocytes was inhibited with HSV-2 infection, whichmight be one means of virus escape at an early phase.The expression of HLA class II antigen may play animportant role in herpes simplex viurs-2 pathogenic-ity and immunity.

A Study of Monocyte Excretion of TNF- α and IL-6 and Monocyte Expression of HLA Class Ⅱ Antigen In Genital Herpes

Objective: To study the role of monocytes in the pathogenesis of genital herpes. Methods: TNF- α and IL-6 levels in 27 cases of genital herpes were detected by enzyme linked immunosorbant assay (ELISA). HLA class Ⅱ antigen expression on monocytes were detected by an alkaline phosphatase anti-alkaline phosphatase method. Results: Compared with normal controls, levels of TNF- a and IL - 6 secreted by monocytes responding to LPS mitogen in vitro were significantly decreased [(3.13 ± 0.44ng/ml) vs (4.68 ± 0.54ng/ml), P<0.05 and (3.32 ± 1.06ng/ml) vs (6.46 ± 1.94ng/ ml), P<0.05, respectively]. HLA class Ⅱ antigen expression on monocytes in the genital herpes group was also significantly decreased [HLA-DR (67.48% ± 1.51%) vs (81.03% ± 1.32%), P<0.01 and HLA-DQ (29.54% ± 1.15%) vs (37.63% ± 1.79%), P <0.01 respectively]. Conclusion: These findings suggest that the decreased monocyte function may contribute to the pathogenesis of genital herpes. Augmenting or inducing monocyte function may be important in the prevention, treatment, and reduction of genital herpes cases.

叶酸通过JNK/p38 MAPK信号通路调节小鼠C2C12成肌细胞分化

目的:观察叶酸(folic acid,FA)对小鼠C2C12成肌细胞增殖和分化的影响并探讨其作用机制。方法:(1)在小鼠C2C12成肌细胞增殖阶段,采用不同浓度(0、2.5、5、10和20μmol/L)的FA处理C2C12细胞,显微镜下观察各组细胞的状态,MTT法检测细胞活力,EdU法检测细胞增殖情况。(2)在小鼠C2C12成肌细胞分化阶段,将细胞分为对照(control,Ctrl)组(0μmol/L FA)和FA组(10μmol/L FA),于分化的第2天和第4天,采用免疫荧光染色和Western blot检测成肌细胞分化相关蛋白成肌细胞决定蛋白1(myoblast determination protein 1,MyoD)、成肌蛋白(myogenin,MyoG)和肌球蛋白重链(myosin heavy chain,MyHC)的表达水平,并统计各组细胞肌管形成情况。(3)在小鼠C2C12成肌细胞分化第4天时,加入FA处理0、1、3和6 h,采用Western blot检测各时点c-Jun氨基末端激酶(c-Jun N-terminal kinase,JNK)、磷酸化JNK(phosphorylated JNK,p-JNK)、p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)和磷酸化p38 MAPK(phosphorylated p38 MAPK,p-p38 MAPK)蛋白水平。(4)将分化4 d的小鼠C2C12成肌细胞分为Ctrl组、FA组、SP600125(JNK特异性抑制剂)组、SB2035805(p38 MAPK特异性抑制剂)组、FA+SP600125组和FA+SB203580组。C2C12成肌细胞先接受10μmol/L的SP600125或SB203580处理1 h,再经10μmol/L的FA处理24 h,FA组经10μmol/L FA处理24 h,Ctrl组不作处理。采用Western blot检测p-JNK、JNK、p-p38 MAPK、p38 MAPK和MyHC蛋白水平。结果:(1)与0μmol/L FA组相比,其余各浓度组的细胞数量明显增多,细胞活力显著提高(P<0.05),EdU阳性细胞率均显著增加(P<0.05)。(2)与Ctrl组相比,FA组MyoD、MyoG和MyHC的表达水平均显著提高(P<0.05),肌管融合指数显著增加(P<0.05或P<0.01)。(3)与0 h组相比,FA处理1、3和6 h后p-JNK/JNK和p-p38 MAPK/p38 MAPK的比值均显著升高(P<0.05或P<0.01),且随着处理时间的延长,p-JNK/JNK和p-p38 MAPK/p38 MAPK的比值呈现逐渐升高的趋势。(4)与Ctrl组相比,FA组p-JNK、p-p38 MAPK和MyHC蛋白水平显著升高(P<0.01);与FA组相比,FA+SP600125组p-JNK和MyHC蛋白水平显著降低(P<0.05),FA+SB203580组p-p38 MAPK和MyHC蛋白水平显著降低(P<0.05或P<0.01)。结论:FA可以通过激活JNK/p38 MAPK信号通路促进小鼠C2C12成肌细胞分化。

槲皮素调控MAPK通路对绝经后骨质疏松大鼠骨形成的影响

目的探讨槲皮素调节MAPK信号通路对绝经后骨质疏松大鼠模型骨形成的影响。方法将SPF级SD雌性大鼠分为假手术组、模型组、槲皮素低、高剂量组及补佳乐组。通过ELISA法检测大鼠血清雌激素E2水平、骨代谢标志物CBF-α1、CTX-Ⅰ、PINP、OC水平、炎性指标IL-6、TNF-α、IL-1β水平;HE染色观察大鼠骨组织形态学变化;TRAP染色观察N.Oc/BS;显微CT扫描大鼠股骨形态,测定大鼠股骨BMD、Tb.N、Tb.Th、Tb.Sp;WB检测MAPK信号通路相关蛋白表达。结果与假手术组相比,模型组大鼠血清E2、CBF-α1、CTX-Ⅰ、PINP、OC水平降低,IL-6、TNF-α、IL-1β水平增加,N.Oc/BS增加,BMD、Tb.N、Tb.Th降低,Tb.Sp增大(P<0.05);与模型组相比,槲皮素低、高剂量组及补佳乐组大鼠血清E2、CBF-α1、CTX-Ⅰ、PINP、OC水平增加,IL-6、TNF-α、IL-1β水平降低,N.Oc/BS降低,BMD、Tb.N、Tb.Th增高,Tb.Sp减小(P<0.05)。假手术组骨组织形态结构正常;模型组骨皮质厚度变薄,骨小梁数量减少且断裂,排列稀疏;槲皮素低、高剂量组及补佳乐组出现新生骨小梁,数量增加,骨组织形态、结构相对完整、清晰。与假手术组相比,模型组MAPK信号通路相关蛋白水平增加(P<0.05);与模型组相比,槲皮素低、高剂量组及补佳乐组MAPK信号通路相关蛋白水平降低(P<0.05)。结论槲皮素能够调节绝经后骨质疏松大鼠雌激素水平,改善骨代谢异常,缓解骨微结构变化,对骨质疏松具有保护作用。可能是通过抑制MAPK信号通路相关蛋白表达、减少破骨细胞形成、减少骨吸收来实现的。

六味地黄汤对阿霉素肾病小鼠尿蛋白及肾小球p-p38 MAPK、α-actinin-4、synaptopodin的影响

目的探讨六味地黄汤对阿霉素肾病(adriamycin nephropaghy,ADRN)小鼠尿蛋白的干预作用及可能机制。方法30只SPF级雄性C57BL/6小鼠随机选取5只为空白组,余下小鼠以单次尾静脉注射阿霉素(0.01 g·kg^(-1))复制ADRN模型,2周后将造模成功的小鼠随机分为模型组、贝那普利组及低、中、高剂量六味地黄汤组,每组5只。空白组、模型组予等体积注射用水灌胃,贝那普利组予0.0013 g·kg^(-1)贝那普利灌胃,低、中、高剂量六味地黄汤组分别予9.75、19.5、39 g·kg^(-1)六味地黄汤灌胃,每日1次,连续8周。自动生化仪检测小鼠24 h尿蛋白定量、血清白蛋白、血清肌酐、血清钾;HE染色法、电镜观察小鼠肾脏病理改变及足突形态;免疫组织化学法、Western bolt检测小鼠肾脏磷酸化p38 MAPK(phosphorylated p38 MAPK,p-p38 MAPK)、α-辅肌动蛋白-4(α-actinin-4)、突触孔蛋白(synaptopodin)的表达;RT-PCR检测小鼠肾脏α-actinin-4、synaptopodin mRNA表达。结果与空白组比较,模型组小鼠体质量、24 h尿量、血清白蛋白降低,24 h尿蛋白定量升高(P<0.05);肾小球系膜细胞增生,部分系膜区扩大、肾小管蛋白管型,间质可见炎性细胞浸润,足突广泛融合;α-actinin-4蛋白及mRNA、p-p38 MAPK蛋白表达升高(P<0.05),synaptopodin蛋白及mRNA表达降低(P<0.05)。与模型组比较,各干预组病理改变及足突融合均得到不同程度改善,贝那普利组及中、高剂量六味地黄汤组24 h尿蛋白定量减少,高剂量六味地黄汤组p-p38 MAPK蛋白表达降低(P<0.05),低、中、高剂量六味地黄汤组synaptopodin蛋白及mRNA表达均升高(P<0.05)。贝那普利组及低、中、高剂量六味地黄汤组组间比较,各指标差异无统计学意义(P>0.05)。结论六味地黄汤可能通过抑制p38 MAPK通路活化和上调α-actinin-4、synaptopodin蛋白及mRNA表达,改善肾脏病理及足突融合,减轻足细胞损伤,减少ADRN小鼠尿蛋白。

吡拉西坦通过MAPK通路治疗大鼠脊髓损伤的疗效观察与机制研究

目的:探讨吡拉西坦通过丝裂原激活蛋白激酶(mitogen-activated protein kinase,MAPK)通路治疗脊髓损伤大鼠的作用机制。方法:将54只体重为80~100 g的6周龄SD雌性健康大鼠采用随机数字表法分为假手术组、脊髓损伤组、吡拉西坦组,每组18只。脊髓损伤组、吡拉西坦组使用打击器建立脊髓损伤模型,假手术组不损伤脊髓。吡拉西坦组按照5 ml·kg-1标准予尾静脉注射吡拉西坦,连续干预3 d,每日1次;其他2组注射等剂量、等次数、等时长的生理盐水。分别于术后1、3、7 d处死大鼠并取材,观察并比较大鼠脊髓损伤行为学评分(Basso,Beattie and Bresnahan locomotor rating scale,BBB)的变化,使用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测脊髓炎症因子白细胞介素-6(interleukin-6,IL-6)、白细胞介素-10(interleukin-10,IL-10)、白细胞介素-1β(interleukin-1β,IL-1β)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平变化,HE染色观察脊髓损伤大鼠的形态学变化,免疫组化观察水通道蛋白-4(aquaporin 4,AQP4)表达水平,蛋白质免疫印迹法(western blotting,WB)观察脊髓损伤后MAPK信号通路在大鼠脊髓中的激活状态。结果:假手术组1、3、7 d的BBB评分均为21分;脊髓损伤组分别为(1±1)、(4±1)、(7±2)分;吡拉西坦组分别为(1±1)、(5±1)、(9±2)分;脊髓损伤组与假手术组比较,差异有统计学意义(P<0.05);吡拉西坦组与脊髓损伤比较,差异有统计学意义(P<0.05)。HE染色结果显示,假手术组形态未见异常。脊髓损伤组在术后1 d时,脊髓组织出现出血、变性;术后3 d,脊髓组织内出现片状坏死区;术后7 d,脊髓组织开始缓慢修复。吡拉西坦组术后1 d,脊髓损伤出血面积较脊髓损伤组减小;术后3 d,坏死区域较脊髓损伤组减少,细胞核消失范围较脊髓损伤组缩小;术后7 d,脊髓开始缓慢恢复。假手术组大鼠造模后1、3、7 d脊髓组织中AQP4染色较淡;脊髓损伤组AQP4染色加深,面积增大;吡拉西坦组AQP4染色较脊髓损伤组变淡,较假手术组阳性细胞略增多,染色微深。造模第1、3、7天,脊髓损伤组IL-6,IL-10,IL-1β和TNF-α水平高于手术组和吡拉西坦组(P<0.05)。与脊髓损伤组比,吡拉西坦组HE染色脊髓出血及坏死区域面积减小,免疫组化显示AQP4染色变淡。WB结果显示,造模第3天,脊髓损伤组pERK,p-JNK和p-p38水平高于假手术组和吡拉西坦组(P<0.05)。结论:吡拉西坦不仅在促进脊髓损伤后的运动功能恢复方面表现出显著效果,而且在减少病变面积、调节AQP4表达以减轻水肿,以及通过调控MAPK信号通路降低炎症反应方面均显示出积极的治疗潜力。

构建类固醇抵抗哮喘Balb/c小鼠模型与MAPK信号通路相关性

目的 构建类固醇抵抗型哮喘Balb/c小鼠模型,初步检测MAPK信号通路关键蛋白表达。方法 纳入SPF级Balb/c小鼠20只,分5组,正常对照组(Ctrl组),哮喘组(BA组),哮喘+地塞米松组(BA+DEX组),类固醇抵抗哮喘组(SRA组),类固醇抵抗哮喘+地塞米松组(SRA+DEX组),采用卵清蛋白(OVA)致敏,H&E染色法观察肺组织病理学改变、ELISA法检测肺泡灌洗液(BALF)细胞计数、IgE水平、炎性因子水平变化证实造模成功;Western Blot检测MAPK信号通路关键蛋白的表达量。结果 (1)H&E染色:SRA+DEX组与SRA组比较:支气管管壁增厚、粘膜上皮细胞增生程度差异不明显、支气管周围炎细胞浸润数量减少不明显。(2)SRA组与BA组比较:BALF中的细胞总数增加,EOS百分比下降,给予激素治疗后,BA+DEX组与BA组比较:BALF中的细胞总数、EOS、NEUT百分比下降、MNCs百分比增加;SRA+DEX组与SRA组比较:BALF中的细胞总数、EOS、NEUT百分比下降、MNCs百分比增加。(3)BA组血清中IgE、BALF中的IL-4、IL-17A、IFN-γ含量较Ctrl组显著升高,给予激素治疗后与BA组相比,BALF中的IL-4、IL-17A、 IFN-γ含量降低;SRA+DEX组与SRA组BALF中的IL-4、IFN-γ含量降低,IL-17A无明显改变。(4)SRA组与BA组比较p-p38磷酸化蛋白水平呈下调、 p-ERK1/2蛋白呈上调的趋势。结论 成功构建类固醇抵抗哮喘小鼠模型,初步发现MAPK信号通路蛋白异常表达与类固醇抵抗型哮喘相关。