Upregulation of PGC-1α expression by pioglitazone mediates prevention of sepsis-induced acute lung injury

Abstract The imbalance between pro-inflammatory M1 and anti-inflammatory M2 macrophages plays a critical role in the pathogenesis of sepsis-induced acute lung injury (ALI). Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) may modulate macrophage polarization toward the M2 phenotype by altering mitochondrial activity. This study aimed to investigate the role of the PGC-1α agonist pioglitazone (PGZ) in modulating sepsis-induced ALI. A mouse model of sepsis-induced ALI was established using cecal ligation and puncture (CLP). An in vitro model was created by stimulating MH-S cells with lipopolysaccharide (LPS). qRT-PCR was used to measure mRNA levels of M1 markers iNOS and MHC-II and M2 markers Arg1 and CD206 to evaluate macrophage polarization. Western blotting detected expression of peroxisome proliferator-activated receptor gamma (PPARγ) PGC-1α, and mitochondrial biogenesis proteins NRF1, NRF2, and mtTFA. To assess mitochondrial content and function, reactive oxygen species levels were detected by dihydroethidium staining, and mitochondrial DNA copy number was measured by qRT-PCR. In the CLP-induced ALI mouse model, lung tissues exhibited reduced PGC-1α expression. PGZ treatment rescued PGC-1α expression and alleviated lung injury, as evidenced by decreased lung wet-to-dry weight ratio, pro-inflammatory cytokine secretion (tumor necrosis factor-α, interleukin-1β, interleukin-6), and enhanced M2 macrophage polarization. Mechanistic investigations revealed that PGZ activated the PPARγ/PGC-1α/mitochondrial protection pathway to prevent sepsis-induced ALI by inhibiting M1 macrophage polarization. These results may provide new insights and evidence for developing PGZ as a potential ALI therapy.

Inhibitory effects of Ginkgo biloba extract on renal inflammation in diabetic nephropathy model mice and its mechanism / 中国药房

OBJECTIVE To investigate the inhibitory effects of Ginkgo biloba extract （GBE） on renal inflammation in diabetic nephropathy （DN） model mice， and its potential mechanism. METHODS KK/Ay mice were fed with high fat and high sugar to induce DN model. They were divided into model group， positive control group [metformin 200 mg/（kg·d）]， GBE low-dose and high-dose groups [100， 200 mg/（kg·d）]， with 6 mice in each group. Six C57BL/6J mice were fed with a regular diet as the control group. Administration groups were given relevant liquid intragastrically， control group and model group were given constant volume of normal saline intragastrically， once a day， for 8 consecutive weeks. The body weight， fasting blood glucose， 24-hour food intake， 24-hour urine output， monocyte chemoattractant protein-1 （MCP-1）， interleukin-12 （IL-12）， IL-10， advanced glycation end products （AGEs）， blood urea nitrogen （BUN） and serum creatinine （Scr） of mice were measured， and the ratio of bilateral kidneys to body weight was also calculated. The pathological injury and fibrotic changes of the renal cortex were observed， and the expressions of macrophage polarization marker proteins [type M1： inducible nitric oxide synthase （iNOS）； type M2： arginase-1 （Arg-1）] and AGEs-the receptor of advanced glycation end products （RAGE）/Ras homolog gene pharm_chenjing@163.com family member A （RhoA）/Rho-associated coiled-coil forming protein kinase （ROCK） signaling pathway-related proteins were determined in renal cortex. RESULTS Compared with the model group， the symptoms such as renal cortical hyperplasia， vacuoles， infiltration of inflammatory cells， and renal cortical fibrosis had been improved in GBE low-dose and high-dose groups； body weight， serum level of IL-10， the expression of Arg-1 in the renal cortex were significantly higher than model group （P＜ 0.01）； fasting blood glucose， 24-hour food intake， 24-hour urine output， serum levels of MCP-1， IL-12， BUN， Scr and AGEs， the ratio of bilateral kidneys to body weight， renal injury score， the proportion of renal interstitial fibrosis， the protein expressions of iNOS， RAGE， RhoA and ROCK1 （except for GBE low-dose group） in renal cortex were significantly lower than model group （P＜0.01）. CONCLUSIONS GBE could improve kidney damage and alleviate inflammatory response in DN model mice， the mechanism of which may be related to inhibiting the AGEs-RAGE/RhoA/ROCK signaling pathway and regulating macrophage polarization.

Modified Xiaoyaosan Alleviates Depression-like Behaviors by Regulating Activation of Hippocampal Microglia Cells in Rat Model of Juvenile Depression / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Baihuan Xiaoyao Decoction （Xiaoyaosan added with Lilii Bulbus and Albiziae Cortex） in alleviating depression-like behaviors of juvenile rats by regulating the polarization of microglia. MethodSixty juvenile SD rats were randomized into normal control， model， fluoxetine， and low-， medium-， and high-dose （5.36， 10.71， 21.42 g·kg-1， respectively） Baihuan Xiaoyao decoction groups. The rat model of juvenile depression was established by chronic unpredictable mild stress （CUMS）. The sucrose preference test （SPT） was carried out to examine the sucrose preference of rats. Forced swimming test （FST） was carried out to measure the immobility time of rats. The open field test （OFT） was conducted to measure the total distance， the central distance， the number of horizontal crossings， and the frequency of rearing. Morris water maze （MWM） was used to measure the escape latency and the number of crossing the platform. The immunofluorescence assay was employed to detect the expression of inducible nitric oxide synthase （iNOS， the polarization marker of M1 microglia） and CD206 （the polarization marker of M2 microglia）. Real-time polymerase chain reaction was employed to determine the mRNA levels of iNOS， CD206， pro-inflammatory cytokines ［tumor necrosis factor （TNF）-α， interleukin （IL）-1β， and IL-6］ and anti-inflammatory cytokines （IL-4 and IL-10） in the hippocampus. Western blotting was employed to determine the protein levels of iNOS and CD206 in the hippocampus. The levels of IL-4 and IL-6 in the hippocampus were detected by enzyme-linked immunosorbent assay. ResultCompared with the normal control group， the model rats showed a reduction in sucrose preference （P<0.05）， an increase in immobility time （P<0.05）， decreased motor and exploratory behaviors （P<0.05）， and weakened learning and spatial memory （P<0.05）. In addition， the model rats showed up-regulated mRNA and protein levels of iNOS and mRNA levels of IL-1β， IL-6， and TNF-α （P<0.05）. Compared with the model group， Baihuan Xiaoyao decoction increased the sucrose preference value （P<0.05）， shortened the immobility time （P<0.01）， increased the motor and exploratory behaviors （P<0.05）， and improved the learning and spatial memory （P<0.01）. Furthermore， the decoction down-regulated the positive expression and protein level of iNOS， lowered the levels of TNF-α， IL-1β， and IL-6 （P<0.01）， promoted the positive expression of CD206， and elevated the levels of IL-4 and IL-10 （P<0.01） in the hippocampus of the high dose group. Moreover， the high-dose Baihuan Xiaoyao decoction group had higher sucrose preference value （P<0.01）， shorter immobility time （P<0.01）， longer central distance （P<0.01）， stronger learning and spatial memory （P<0.01）， higher positive expression and protein level of iNOS （P<0.01）， lower levels of TNF-α， IL-1β， and IL-6 （P<0.05， P<0.01）， lower positive expression and mRNA level of iNOS （P<0.05）， and higher levels of IL-4 and IL-10 （P<0.05， P<0.01） than the fluoxetine group. ConclusionBaihuan Xiaoyao decoction can improve the depression-like behavior of juvenile rats by inhibiting the M1 polarization and promoting the M2 polarization of microglia in the hippocampus.

Effect of Xuefu Zhuyu Capsules on Polarization of Macrophages in Mice with Atherosclerosis / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Xuefu Zhuyu capsules against atherosclerosis via regulating polarization of macrophages based on Notch1/jagged canonical Notch ligand 1（Jagged1）/Hes family BHLH transcription factor 1（Hes1） signaling pathway. MethodThe mouse models with atherosclerosis were prepared by feeding the mice with an ApoE-/- high-fat diet for four weeks， and they were randomly divided into the model group， Xuefu Zhuyu capsule group， and atorvastatin group. C57BL/6 mice were fed as a normal group. The Xuefu Zhuyu capsule group was intragastrically given Xuefu Zhuyu capsules （0.728 g·kg-1·d-1）， and the atorvastatin group was intragastrically given atorvastatin tablet （6.07 mg·kg-1·d-1）. The normal group and the model group were given equal volume of the deionized water by intragastric administration， and the intervention lasted for 12 weeks. Aortic plaque morphology was observed by hematoxylin-eosin （HE） staining， and aortic plaque area and lipid deposition were observed by oil red O staining. The positive expression levels of CD86 and CD206 in aortic tissue were detected by immunohistochemistry， and serum levels of tumor necrosis factor （TNF）-α， interleukin（IL）-1β， transforming growth factor （TGF）-β1， and IL-10 were detected by enzyme-linked immunosorbent assay （ELISA）. The relative mRNA expressions of inducible nitric oxide synthase （iNOS）， arginase-1 （Arg-1）， Notch1， Jagged1， and Hes1 in aortic tissue were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The relative protein expression of iNOS， Arg-1， Notch1， Jagged1， and Hes1 in aortic tissue was detected by Western blot. ResultCompared with the normal group， the model group had significant aortic plaque and lipid deposition， and the expression levels of pro-inflammatory cytokines TNF-α and IL-1β were increased （P<0.01）. The expression level of anti-inflammatory cytokine TGF-β1 showed a downward trend， but the difference was not statistically significant. The mRNA and protein expressions of iNOS were increased （P<0.01）. The protein expression of Arg-1 was decreased （P<0.01）， and the mRNA expression of related pathway molecule Jagged1， as well as the protein expressions of Notch1， Jagged1， and Hes1 were increased in the model group （P<0.05， P<0.01）. Compared with those in the model group， the plaque area and lipid deposition had a decreasing trend in the Xuefu Zhuyu capsule group， and the expressions of TNF-α and IL-1β showed a downward trend. The expression of TGF-β1 was increased （P<0.05）， and the expression of macrophage marker CD86 was decreased. The mRNA and protein expressions of iNOS were decreased （P<0.01）. The mRNA and protein expressions of Arg-1 were increased （P<0.05， P<0.01）. Furthermore， the mRNA and protein expressions of Notch1， Jagged1， and Hes1 were decreased （P<0.01）. ConclusionXuefu Zhuyu capsules can reduce aortic plaque area and lipid deposition in mice with atherosclerosis， alleviate inflammation， inhibit M1 macrophages， and promote the expression of M2 macrophages， and the mechanism may be related to the regulation of Notch1/Jagged1/Hes1 signaling pathway.

Effects of Siglec-E on parthenolide inhibiting microglia M1 polarization and targeting MAPK/NF-κB pathway / 陆军军医大学学报

Objective To explore the impact of the sialic acid binding lectin-E(Siglec-E)on the inhibitory properties of parthenolide(PTL)against lipopolysaccharide(LPS)-induced M1 polarization of microglia(BV2).Methods ①Single cell sequencing data of Siglece related mouse brain tissue was obtained from Gene Expression Omnibus(GEO)database and divided into the WT group(n=3)and the Siglece-/-group(n=4).The microglia cells were screened,and the enrichment analysis was performed to analyze related differential genes and pathways.BV2 cells were constructed by the shRNA interference technique and were divided into NC-shRNA and Siglece-shRNA to detect the expression level of Siglec-E(Siglece).② NC-shRNA and Siglece-shRNA cells were respectively divided into the Control group,LPS group,PTL group and PTL+LPS group(n=3).The mRNA levels of markers of M1 polarization in microglia,iNOS,IL-1 β and IL-6,were detected by RT-qPCR.Siglecefl/fl and Cx3cr1cre mice were mated to obtain microglia-specific Siglece deletion(Siglecefl/fl×Cx3cr1cre)mice,and LPS-induced neuroinflammation model was established.③ Nine WT and Siglecefl/fl×Cx3cr1cre male mice were assigned to the Control group,LPS group and PTL+LPS group(n=3).RT-qPCR,immunofluorescence assay and Western blotting were used to verify the knock-out effect and polarization-related pathways,and to investigate the mechanism of Siglec-E affecting PTL inhibition of M1 polarization of microglia.Results Compared with the NC-shRNA group,the expression of Siglec-E in the Siglece-shRNA group was significantly decreased(P<0.01),indicating that the Siglec-E knock-down cell model was successfully established.With the stimulation of LPS,mRNA levels ofiNOS,IL-1 β and IL-6 were significantly up-regulated compared with the Control group both in shRNA cells and Siglece-shRNA cells(P<0.01).With the influence of PTL and LPS,the markers of M1 polarization in NC-shRNA cells mentioned before were significantly decreased(P<0.05),while for Siglice-shRNA cells,there were no significant changes in the markers of M1 polarization.PTL inhibited the phosphorylation of JNK and IκB protein(P<0.01)and the nuclear translocation of NF-κB in BV2 cells,down-regulated Siglec-E,and weakened the inhibitory effect.Compared with mice in the WT group,the expression of Siglec-E in microglia of Siglecefl/fl×Cx3cr1cre mice was decreased significantly(P<0.01),and the inhibitory effect of PTL on the phosphorylation of NF-κB in microglia of Siglecefl/fl×Cx3cr1cre mice was also decreased.Conclusion The absence of Siglec-E in microglia attenuates the inhibition of M1 polarization by the MAPK/NF-κB pathway targeted by PTL.

Research progress of microglia polarization involved in chronic pain / 临床麻醉学杂志

Chronic pain has been a prominent public health issue in China for years,affecting over 30%of the population.The mechanism of chronic pain has always been a controversial and difficult topic of pain medicine research.The polarization of microglia inherent in the central nervous system when the external microenvironment changes and the subsequent neuroinflammatory response are critical in chronic pain.Microglia can polarize into pro-inflammatory M1 or anti-inflammatory M2 phenotypes during neuroin-flammatory reactions,exerting neurotoxic or neuroprotective effects in the nervous system,respectively.The aim of the article is proposed to provide an overview of the main mechanisms of microglial polarization and-how it might contribute to chronic pain.

M2 Macrophages regulate cementogenic differentiation of human periodontal ligament stem cells by modu-lating oxidant-antioxidant system and mitophagy / 实用口腔医学杂志

Objective:To investigate the effects of macrophage(Mφ)polarization on the cementogenic differentiation of human perio-dontal ligament stem cells(hPDLSCs)and the underlying mechanism.Methods:Human monocytic THP-1 cells were induced to M0,M1 and M2 Mφ subsets,then RPM1 1640 medium or supernatants of different Mφ phenotypes were mixed with an equal volume of ce-mentoblastic induction medium to generate conditioned mediums(CMs),and termed as CM-Control,CM-M0,CM-M1 and CM-M2,respectively.hPDLSCs were cultured with different CMs,and the hPDLSCs sheets were then wrapped around treated dentin matrix(TDM)to generate cell sheet/dentin complexes.The complexes were subcutaneously implanted into nude mice.The cementum-like tissue formation was evaluated by HE staining,immunofluorescent staining(IMF)and qRT-PCR were used to detect the expression level of cementogenic differentiation-related markers bone sialoprotein(BSP),cementum attachment protein(CAP)and cementum pro-tein-1(CEMP-1),oxidant-antioxidant system-related markers superoxide dismutase 1(SOD1)and nuclear factor erythroid 2-related factor 2(NRF2),mitophagy-related markers PTEN induced putative kinase 1(PINK1)and microtubule asso ciated proteins 1A/1B light chain 3(LC3).Results:In vivo,CM-M2-treated hPDLSCs(CM-M2)group formed more cementum-like tissues and expressed higher protein levels of CAP,CEMP-1,SOD1,PINK1 and LC3 than that in other groups.In vitro tests showed that,compared with CM-Control group,hPDLSCs incubated with CM-M2 increased the levels of BSP(P＜0.01),CAP(P＜0.001),CEMP-1(P＜0.01)and SOD1(P＜0.05),while no statistically significant difference was detected for NRF2(P＞0.05),and increasedthe expression of PINK1(P＜0.05).Conclusion:M2 Mφ regulate the cementogenic differentiation of hPDLSCs possibly via modulating oxidant-antioxidant system and mitophagy.

Effect of heme oxygenase-1-mediated atorvastatin on macrophage polarization and cholesterol accumulation / 中国组织工程研究

BACKGROUND:Studies have shown that atorvastatin can up-regulate the expression of heme oxygenase-1 and enhance the anti-inflammation and anti-oxidative damage ability of cells.However,whether atorvastatin can regulate macrophage polarization,inhibit inflammation and reduce cholesterol accumulation by inducing heme oxygenase-1 expression remains unclear. OBJECTIVE:To investigate the effect of atorvastatin on polarization,inflammation and cholesterol content of oxidized low-density lipoprotein stimulated RAW264.7 macrophages by inducing heme oxygenase-1 expression and its related mechanism. METHODS:Firstly,RAW264.7 cells were randomly divided into six groups and incubated with different concentrations of atorvastatin for 24 hours.The expression of heme oxygenase-1 protein and cell activity were detected to explore the optimal dose of atorvastatin for subsequent studies.RAW264.7 cells were randomly divided into control group,atorvastatin group and heme oxygenase-1 inhibition group.Cells were preincubated with pure medium,atorvastatin 20 μmol/L and atorvastatin 20 μmol/L + zinc protoporphyrin IX 10 μmol/L for 24 hours,and then oxidized low-density lipoprotein 50 mg/L was added for 48 hours.The polarization of macrophages was detected by flow cytometry.The secretion of inflammatory factors such as transforming growth factor β,interleukin 10,interleukin 1β,and tumor necrosis factor α was detected by ELISA.The expression levels of heme oxygenase-1,LC3II,LC3I,P62,PPARγ and ABCA1 were detected by western blot assay.The intracellular cholesterol content was measured with the oxidose method and the accumulation degree of intracellular lipid droplets was evaluated by oil red O staining. RESULTS AND CONCLUSION:(1)Atorvastatin could induce the expression of heme oxygenase-1 protein in macrophages in a dose-dependent manner.(2)Oxidized low-density lipoprotein could induce macrophages to polarize towards M1,secrete proinflammatory factors,and increase the accumulation of intracellular cholesterol.(3)Compared with the control group,the heme oxygenase-1 protein expression of macrophages was increased after atorvastatin intervention,and the cells turned to M2-type polarization and mainly secreted anti-inflammatory factors such as transforming growth factor-β and interleukin-10.PPARγ,ABCA1,LC3II/I and other signal molecules reflecting cholesterol efflux and autophagy increased,and the contents of intracellular cholesterol and lipid droplets decreased significantly(P<0.05).(4)The heme oxygenase-1 inhibition group treated with zinc protoporphyrin IX significantly reversed the above changes in the atorvastatin group.(5)The results have shown that atorvastatin may promote the polarization of macrophages stimulated by oxidized low-density lipoprotein to M2 type and inhibit inflammation by up-regulating the expression of heme oxygenase-1 and by up-regulating PPARγ/ABCA1 signaling pathway and enhancing autophagy.Atorvastatin can increase the outflow of intracellular cholesterol and reduce the accumulation of intracellular lipids.

Prussian blue nanoparticles promote wound healing of diabetic skin / 中国组织工程研究

BACKGROUND:Inflammation,oxidative stress and bacterial infection are the main causes of delayed wound healing in diabetes.In recent years,various inorganic nanomaterials have been widely used in the treatment of skin wound healing due to their antibacterial activities,but their effects on anti-oxidation and anti-inflammation are limited. OBJECTIVE:To investigate the effect of Prussian blue nanoparticles on the wound repair of diabetes in terms of antioxidant,anti-inflammatory and photothermal antibacterial activities. METHODS:Prussian blue nanoparticles were prepared and characterized.(1)In vitro:The biocompatibility of Prussian blue nanoparticles with different concentrations was detected by MTT assay.The cytoprotective effect of Prussian blue nanoparticles and the intracellular reactive oxidative species level were examined under the condition of hydrogen peroxide.The ability of Prussian blue nanoparticles to decompose hydrogen peroxide and superoxide anion radicals was tested;the effect of Prussian blue nanoparticles on lipopolysaccharide-induced macrophage inflammation was investigated.The photothermal antibacterial activity of Prussian blue nanoparticles was detected by the plate colony counting method.(2)In vivo:ICR mice were intraperitoneally injected with streptozotocin to establish a diabetes mouse model.After the model was successfully established,a 6 mm wound was created on the back with a hole punch.There were the control group(no treatment),the Prussian blue group and the Prussian blue with light group.The wound healing and histomorphological changes were observed. RESULTS AND CONCLUSION:(1)In vitro:Prussian blue nanoparticles in 25-200 μg/mL were non-toxic to cells.Prussian blue nanoparticles had the extremely strong antioxidant capacity and mitigated the intracellular reactive oxidative species at a high oxidative stress environment,resulting in a pronounced cytoprotective effect.The Prussian blue nanoparticles not only exhibited hydrogen peroxide degradation activity but also showed strong superoxide scavenging ability.Prussian blue nanoparticles also displayed significant anti-inflammatory activity and extremely strong antibacterial ability after light irradiation.(2)In vivo:After 14 days,the wound sizes of the Prussian blue group and Prussian blue with light group were significantly reduced,and the healing speed of Prussian blue with light group was the fastest.Hematoxylin-eosin and Masson staining showed a lot of granulation tissue formation and collagen deposition in the Prussian blue group and the Prussian blue with light group,of which the Prussian blue with light group was the most.Immunofluorescence staining displayed that,compared with the control group,the expressions of α-SMA and CD31 were increased significantly in Prussian blue group and Prussian blue with light group(P<0.05),but F4/80 expression was decreased significantly in Prussian blue group and Prussian blue with light group(P<0.05),indicating more obvious improvement in the Prussian blue with light group.(3)These results showed that Prussian blue nanoparticles could promote the skin wound healing of the diabetes mouse model by exerting anti-inflammatory,antioxidant and antibacterial effects.

Overexpression of miR-378a promotes macrophage M2 polarization and inhibits M1 polarization / 中国组织工程研究

BACKGROUND:M2 macrophages have the function of reducing inflammatory factors and promoting tissue healing.Therefore,how to regulate M2 polarization of macrophages has been a hot research topic in recent years,and some miRNAs have been found to have this function. OBJECTIVE:To investigate the effects of miR-378a on the polarization of the Raw264.7 macrophage cell line. METHODS:The M1 polarization of macrophages was induced by lipopolysaccharide and interferon-γ.Interleukin-4 induced M2 polarization and the expression of endogenous miR-378a in each cell type was detected using qRT-PCR to verify whether miR-378a was involved in the polarization of macrophages.By transfection with lentivirus as the vector of overexpression of miR-378a,the stable expression of miR-378a cell lines was screened.Macrophage M1 polarization was induced synergically by lipopolysaccharide and interferon-γ.Macrophage M2 polarization was induced by interleukin-4.The levels of M1/M2 polarization-related cytokines in the supernatant of the macrophage culture medium were determined by enzyme-linked immunosorbent assay.qRT-PCR was used to detect the polarization characteristics of M1/M2-type macrophages and the mRNA expression levels of related cytokines. RESULTS AND CONCLUSION:(1)The expression level of endogenous miR-378a in Raw264.7 cells of each group increased after macrophage polarization.(2)Compared with the non-transfected group,the expressions of proinflammatory cytokine-induced nitric oxide synthase,tumor necrosis factor-α,interleukin-6 and interleukin-1β in macrophage M1 induced polarization were significantly decreased in the miR-378a transfection group(P<0.05);the levels of inducible nitric oxide synthase,tumor necrosis factor-α and interleukin-6 in cell supernatant were also significantly decreased(P<0.05).(3)Compared with the non-transfected group,the expressions of CD206,interleukin-10 and arginase-I in macrophage M2 induced polarization were significantly increased(P<0.05);the levels of CD206 and interleukin-10 in cell supernatant were also significantly increased(P<0.05)in the miR-378a transfection group.(4)It is indicated that overexpression of miR-378a promotes the M2 polarization of macrophages and inhibits the M1 polarization of macrophages.

Placenta-derived mesenchymal stem cells in promoting acute skin wound healing in rats / 中国组织工程研究

BACKGROUND:Currently,a variety of mesenchymal stem cells have been confirmed to have the effect of promoting wound repair,but there is still a lack of relevant research on whether placenta-derived mesenchymal stem cells can promote acute skin wound healing. OBJECTIVE:To investigate the effect of placenta-derived mesenchymal stem cell transplantation on the healing of acute skin wound in rats. METHODS:Twenty SD rats were divided into PBS group and stem cell group by the random number table method,with 10 rats in each group.All rats were selected to establish a full-thickness skin defect model.In the PBS group and stem cell group,PBS buffer and placenta-derived mesenchymal stem cells were immediately injected on the wound surface and wound margin immediately and on day 8 after modeling.The wound healing was observed immediately and on days 2,4,6,8,10,12,and 14 after modeling.The skin tissue of the wound surface was taken on day 14 and treated with hematoxylin-eosin staining,Masson staining,immunohistochemical staining and immunofluorescence staining. RESULTS AND CONCLUSION:(1)The wound surface of the rats in each group decreased with the prolongation of treatment time.The wound healing rate and wound epithelization rate of the stem cell group at 14 days were higher than those of the PBS group(P<0.01),and the wound contracture rate was lower than that of the PBS group(P<0.01).(2)The results of hematoxylin-eosin staining showed that the skin wound healing of the stem cell group was better than that of the PBS group;the degree of wound epithelization was higher,and the morphology of collagen fibers was close to that of normal skin.(3)Masson staining results showed that compared with the PBS group,collagen fibers in the skin wound tissue of the stem cell group were significantly increased and thicker,and the content of collagen fibers in the new tissue was significantly higher than that of the PBS group(P<0.01).(4)Immunohistochemical staining showed that the number of new capillaries in the stem cell group was higher than that in the PBS group(P<0.01),while the expressions of tumor necrosis factor-α and interleukin-6 were lower than those in the PBS group(P<0.01).(5)Immunofluorescence staining showed that the number of M2 macrophages in the new wounds of the stem cell group was higher than that of the PBS group(P<0.01),while the number of M1 macrophages was less than that in the PBS group(P<0.01).These findings indicate that placenta-derived mesenchymal stem cells can accelerate skin wound healing,promote wound epithelization,and reduce wound contracture,which may be related to the promotion of capillary angiogenesis,regulation of collagen fiber production,inhibition of inflammation,and regulation of macrophage polarization to M2 type.

The role of macrophage polarization in the pathogenesis and treatment of periodontitis / 中国组织工程研究

BACKGROUND:Host immune response triggered by plaque biofilm is an initiator of periodontitis progression and destruction.Macrophages are an important component of the innate immune response,which play an important role in inflammation occurrence and development. OBJECTIVE:To review the relationship between macrophage polarization and periodontitis and the related progress in the treatment of periodontitis by regulating macrophage polarization. METHODS:PubMed and CNKI databases were searched for relevant literature published from 1990 to 2023,with"macrophage polarization,M1/M2 macrophage,periodontitis,periodontitis treatment,macrophage polarization and periodontitis,osteoimmunology,ferroptosis,macrophage polarization and ferroptosis,periodontitis and ferroptosis"as the English and Chinese search terms.After the initial screening,96 articles were selected for review. RESULTS AND CONCLUSION:The switch between different phenotypes of macrophages is closely related to the tissue destruction caused by periodontitis,and various cytokines and inflammatory mediators secreted from macrophages are involved in the destruction and repair of periodontal tissue.Therefore,regulation of macrophage polarization and cytokine secretion in inflammatory state helps to alleviate periodontitis inflammation and improve the periodontal microenvironment,thereby reducing tissue destruction or promoting periodontal tissue regeneration.Many studies have been conducted to develop drugs or biomaterials to modulate macrophage function for the purpose of immunomodulatory treatment of periodontitis.However,macrophages act throughout the development of periodontitis and play an important role in the process of anti-infection,bone destruction and bone repair,and polarization is a complex and dynamic process influenced by many factors.Therefore,further exploration on possible mechanisms is still needed to clarify the interaction between materials or drugs and macrophages.

Silk fibroin methacryloyl hydrogel loaded with Scriptaid regulates polarization of microglia cells / 中国组织工程研究

BACKGROUND:Microglia cells play a major role in maintaining the balance as well as the development and function reconstruction of the central nervous system.As a histone deacetylase inhibitor,Scriptaid can inhibit neuroinflammation and enhance neuroprotection. OBJECTIVE:To investigate the effect of silk fibroin methacryloyl hydrogel loaded with Scriptaid on the behaviors of microglia cells. METHODS:Microglia(BV2 cells)were cultured in medium containing different concentrations of Scriptaid(0,0.1,0.5,1,2,5,10 μmol/L).The optimal concentration of Scriptaid was screened by the CCK-8 assay and live/dead cell staining.Silk fibroin methacryloyl hydrogels loaded with or without Scriptaid were prepared using photocuring.The micromorphology,swelling properties,mechanical properties,slow release properties,and hydrophilicity of the hydrogels were characterized.Microglia(BV2 cells)were inoculated in the subventricular region of 24-well Transwell and cultured in five groups.In the control group,the cell culture medium was added to the lower chamber.In the lipopolysaccharide group,Scriptaid group,hydrogel group,and drug-loaded hydrogel group,cell culture media containing lipopolysaccharide were added into the lower chamber.After 24 hours of lipopolysaccharide intervention,in the Scriptaid group,hydrogel group and drug-loaded hydrogel group,Scriptaid,silk fibroin methacryloyl hydrogel,and silk fibroin methacryloyl hydrogel loaded with Scriptaid were added to the upper chamber,respectively.The culture medium was replaced with ordinary culture medium and continued to culture for 24 hours.The cell viability was detected by CCK-8 assay,and the cell phenotype was detected by immunofluorescence staining of induced nitric oxide synthase and arginase 1. RESULTS AND CONCLUSION:(1)Compared with the group without Scriptaid,the viability and number of BV2 cells were decreased after Scriptaid added.When Scriptaid 2 μmol/L or above was added,the cell viability was lower than the standardized cell viability(70%),and the number of BV2 cells was significantly reduced.Therefore,1 μmol/L Scriptaid was selected to be loaded into the hydrogel.(2)Characterization experiments showed that the addition of Scriptaid did not affect the microscopic morphology,swelling rate of water absorption,compression modulus and hydrophilicity of silk fibroin methacryloyl hydrogel,and silk fibroin methacryloyl hydrogel had slow release performance.(3)The result of CCK-8 assay showed that compared with the control group,silk fibroin methacryloyl hydrogel significantly increased the viability of BV2 cells(P<0.001).(4)Immunofluorescence staining showed that compared with the control group,the expression of inducible nitric oxide synthase was increased in the lipopolysaccharide group(P<0.01);the expression of inducible nitric oxide synthase was decreased(P<0.01)and the expression of arginase 1 was increased(P<0.001)in the drug-loaded hydrogel group;the expression of arginase 1 was increased in the Scriptaid group(P<0.01).(5)The results indicate that Scriptaid-loaded silk fibroin methacryloyl hydrogel is able to promote polarization of microglia to the M2 type after lipopolysaccharide induction.

Indolepropionic acid inhibition of microglial cell M1 polarization for treatment of spinal cord injury / 中国组织工程研究

BACKGROUND:Indolepropionic acid has been shown to reduce diabetes-induced central nervous system inflammation.However,there is a lack of research on whether to inhibit microglia M1 polarization for the treatment of spinal cord injury. OBJECTIVE:To investigate the mechanism of indolepropionic acid inhibition of microglial cell M1 polarization for the treatment of spinal cord injury through cell and animal experiments. METHODS:(1)In vitro experiments:BV2 cell viability was assessed using the CCK-8 assay to determine optimal concentrations of indolepropionic acid.Subsequently,BV2 cells were categorized into control group,administration group(50 μmol/L indolepropionic acid),lipopolysaccharide group(100 ng/mL lipopolysaccharide),and treatment group(100 ng/mL lipopolysaccharide + 50 μmol/L indolepropionic acid).Nitric oxide content was quantified using the Griess method.Real-time quantitative PCR and western blot assay were employed to measure mRNA and protein levels of pro-inflammatory factors.Cell immunofluorescence staining was conducted to assess inducible nitric oxide synthase expression.The Seahorse assay was employed to assess glycolytic stress levels in BV2 cells.(2)In vivo experiments:30 SD rats were randomly divided into three groups:sham surgery group,spinal cord injury group,and indolepropionic acid group.Motor function recovery in rats after spinal cord injury was assessed using BBB scoring and the inclined plane test.Immunofluorescence staining of spinal cord tissue was conducted to evaluate the expression of inducible nitric oxide synthase in microglial cells.ELISA was employed to measure protein expression levels of the pro-inflammatory cytokines interleukin-1β and tumor necrosis factor-α in spinal cord tissue. RESULTS AND CONCLUSION:(1)In vitro experiments:Indolepropionic acid exhibited significant suppression of BV2 cell viability when its concentration exceeded 50 μmol/L.Indolepropionic acid achieved this by inhibiting the activation of the nuclear factor κB signaling pathway,thereby suppressing the mRNA and protein expression levels of pro-inflammatory cytokines(interleukin-1β and tumor necrosis factor-α),as well as the M1 polarization marker,inducible nitric oxide synthase,in BV2 cells.Additionally,indolepropionic acid notably reduced the glycolytic level in BV2 cells induced by lipopolysaccharides.(2)In vivo experiments:Following indolepropionic acid intervention in spinal cord injury rats,there was a noticeable increase in BBB scores and the inclined plane test angle.There was also a significant decrease in the number of M1-polarized microglial cells in spinal cord tissue,accompanied by a marked reduction in the protein expression levels of pro-inflammatory cytokines(interleukin-1β and tumor necrosis factor-α).(3)These results conclude that indolepropionic acid promotes functional recovery after spinal cord injury by improving the inflammatory microenvironment through inhibition of microglia M1 polarization.

Effect of interleukin-34 on the polarization and migration ability of macrophages derived from human peripheral blood monocytes / 新乡医学院学报

Objective To investigate the effects of interleukin(IL)-34 on the polarization and migration ability of macrophages derived from human peripheral blood monocytes.Methods The CD14+monocytes were isolated from human peripheral blood monocytes by immunomagnetic bead sorting,and the purity of CD14+monocytes was detected by flow cytometry.The CD14+monocytes were divided into M1 type group,IL-34-M1 type group,M2 type group and IL-34-M2 type group.The cells in the M1 type group and IL-34-M1 type group were added granulocyte-macrophage colony stimulating factor(GM-CSF)to induce for 5 days,and half of the fluid was changed,and then the interferon-γ,lipopolysaccharides,IL-6 and GM-CSF were added for another 4-day induction;the cells in the M2 type group and IL-34-M2 type group were added macrophage colony stimulating factor(M-CSF)to induce for 5 days,and half of the fluid was changed,and M-CSF,IL-4,IL-6,and IL-13 were added for another 4-day induction.The cells in IL-34-M1 group and IL-34-M2 group were co-induced with IL-34 at the beginning of induction and on the 5th day of induction.On the 9th day of induction,the proportion of CD14+CD86+cells(M1 type macrophages)and CD14+CD163+cells(M2 type macrophages)in each group was detected by flow cytometry,and the migration ability of cells in the M2 type group and IL-34-M2 type group was detected by the Transwell chamber experiments.Results High purity CD14+monocytes were obtained through magnetic bead sorting,with a CD14 positive rate of(96.77± 2.72)％,which could be used for macrophage induction.The proportion of CD14+CD86+cells in the M1 type group and IL-34-M1 type group was(43.20±7.59)％and(27.87±2.06)％,respectively.The proportion of CD14+CD163+cells in the M2 type group and IL-34-M2 type group was(47.70±4.49)％and(58.95±3.65)％,respectively;the proportion of CD14+CD86+cells in the IL-34-M1 type group was significantly lower than that in the M1 type group(P＜0.05),while the proportion of CD14+CD163+cells in the IL-34-M2 type group was significantly higher than that in the M2 type group(P＜0.05).The number of migrating cells of macrophages in the M2 type group and IL-34-M2 type group was 97.8±9.0 and 205.6±21.9,respectively;the number of migrating cells of macrophages in the IL-34-M2 type group was significantly higher than that in the M2 type group(P＜0.05).Conclusion IL-34 can inhibit the polarization of macrophages derived from human monocytes cells towards M1 type,promote the polarization of macrophages towards M2 type,and enhance the migration ability of M2 type macrophages.

Effect of HtrA serine peptidase 3 gene on choroidal neovascularization and M2 macrophage polarization / 眼科新进展

Objective To investigate the effect of the HtrA serine peptidase 3(HTRA3)gene on choroidal neovascu-larization(CNV)and M2 macrophage polarization.Methods Fasting venous blood was collected from 30 patients with wet age-related macular degeneration(wAMD group)and 30 healthy subjects(normal group).The serum HTRA3 messen-ger ribonucleic acid(mRNA)level was detected by quantitative reverse transcription polymerase chain reaction(qRT-PCR).RF/6A cells were randomly divided into the control group,NC-sh group and HTRA3-sh group.Lentiviral vectors of NC-shRNA and HTRA3-shRNA were transfected into RF/6A cells in the NC-sh group and HTRA3-sh group by Lipo-fectamine2000.HTRA3 transfection was detected by qRT-PCR and Western blot.Then,the RF/6A cells were randomly di-vided into the N group,H group,H+NC-sh group and H+HTRA3-sh group.After cell transfection,RF/6A cells in the N group were cultured in a RPMI 1640 complete medium at a normoxia state,and cells in other groups were cultured in a RP-MI 1640 medium with 200 mmol·L-1 CoCl2 at a hypoxia state.Tubule formation was measured by Matrigel.The C57BL/6J mice were divided into the control group,CNV group,CNV+NC-sh group and CNV+HTRA3-sh group,with 12 mice in each group.Mice in the control group were unmodeled mice,and mice in the other groups were laser-induced CNV model mice.NC-shRNA and HTRA3-shRNA lentiviral vectors with a titer of 1 × 1011 TU·mL-1 were administered to mice in the CNV+NC-sh group and CNV+HTRA3-sh group via intravitreal injection.Mice in the control group and CNV group were in-jected with phosphate buffered saline.After 7 days of treatment,the mice were examined by fundus fluorescein angiogra-phy,and the eyeballs received hematoxylin & eosin staining.The mRNA levels of HTRA3,chitinase-like protein 3(Ym-1),arginase 1(Arg-1),inducible nitric oxide synthase(iNOS),cyclooxygenase-2(COX-2)and vascular endothelial growth factor(VEGF)in RF/6A cells or choroidal tissues were detected by qRT-PCR.The protein expression levels of HTRA3,VEGF and nuclear factor kappa B(NF-κB)p65 in RF/6A cells or choroidal tissues were detected by Western blot.Re-sults Compared with the normal group,serum HTRA3 mRNA level of patients in the wAMD group increased(t=11.804,P＜0.001).Compared with the control group and NC-sh group,the expressions of HTRA3 mRNA and protein in RF/6A cells in the HTRA3-sh group decreased(all P＜0.05).Compared with the N group,the number of closed lumen and the mRNA and protein expressions of HTRA3 and VEGF in RF/6A cells in the H group increased(all P＜0.05).Compared with the H+NC-sh group,the number of closed lumen and the mRNA and protein expressions of HTRA3 and VEGF decreased in RF/6A cells in the H+HTRA3-sh group(all P＜0.05).Compared with the control group,the mRNA and protein expression levels of HTRA3 increased,the relative fluorescence intensity of CNV increased,the mRNA levels of Ym-1 and Arg-1 in-creased,the iNOS and COX-2 mRNA levels decreased,and the NF-κB p65 protein expression level increased in mice of the CNV group(all P＜0.05).Compared with the CNV+NC-sh group,the mRNA and protein expression levels of HTRA3 de-creased,the relative fluorescence intensity of CNV decreased,the mRNA levels of Ym-1 and Arg-1 decreased,the mRNA levels of iNOS and COX-2 increased,and the NF-κB p65 protein expression level decreased in mice of the CNV+HTRA3-sh group(all P＜0.05).Conclusion Down-regulation of HTRA3 can inhibit the formation of CNV and the polarization of M2 macrophages.HTRA3 may be an important potential target for the prevention and treatment of wAMD.

Macrophage polarization in calcium oxalate nephrolithiasis:unraveling its role and influencing factors / 中国病理生理杂志

The most prevalent kind of renal calculi,calcium oxalate(CaOx),is characterized by its propensi-ty for recurrence in the urinary system.The development of CaOx renal calculi is greatly affected by macrophage polariza-tion.Particular oxalate causes an imbalance in macrophage polarization,which skews the M1/M2 ratio and makes it easier for CaOx crystals to accumulate in the kidneys and grow into calcium plaques in the renal papilla.Notably,M2 macro-phages can prevent CaOx renal calculi by consuming crystals and reducing inflammatory stress.As a result,immunothera-peutic techniques that alter M1 and M2 macrophage polarization are extremely promising for preventing CaOx renal calcu-li.To clarify the respective roles of M1 and M2 macrophages in the formation of CaOx crystals and provide insights for de-veloping immunotherapeutic interventions against CaOx renal calculi,this review summarizes the mechanisms underlying macrophage polarization in the genesis of CaOx renal calculi.

Vaspin improves insulin sensitivity in type 2 diabetes rats by regulating the polarization of adipose tissue macrophages / 中华内分泌代谢杂志

Objective:This study aimed to explore the effect of Vaspin on adipose tissue macrophage polarization and its underlying mechanism.Methods:Fifty male SD rats, aged 8 weeks, were chosen and randomly allocated into three groups: the normal control(NC), the type 2 diabetes(T2DM), and various concentrations of Vaspin intervention(V1: 480 ng/kg, V2: 960 ng/kg, V3: 1 440 ng/kg). Vaspin was administered via intraperitoneal injection for 8 weeks. Glucose tolerance and insulin sensitivity were evaluated via intraperitoneal glucose tolerance test(IPGTT), intraperitoneal insulin tolerance test(IPITT) and hyperinsulinemic-euglycemic clamp. Adipose tissue inflammation and macrophage polarization were assessed using immunofluorescence, RT-PCR and western blotting.Results:After 8 weeks of intervention, there were no statistically significant differences in body weight and blood lipid levels among groups. IPGTT, IPITT, and hyperinsulinemic-euglycemic clamp experiments demonstrated that Vaspin intervention improved blood glucose and insulin sensitivity, exhibiting a dose-dependent manner( P<0.05). IF and RT-PCR showed that Vaspin downregulated the expression of CD11c, IL-1β, and TNF-α in eWAT, while upregulating the expression of CD206, IL-10, and PPARγ, which correlated with Vaspin concentration( P<0.05). ELISA revealed that Vaspin intervention reduced the concentrations of IL-1β and TNF-α in serum, while increasing the concentration of IL-10( P<0.05). Western blotting demonstrated that Vaspin downregulated iNOS protein expression, while upregulating Arg1, p-Akt, and PPARγ expression in a dose-dependent manner( P<0.05). Conclusion:Vaspin promotes M2 polarization of adipose tissue macrophages via PPARγ pathway, leading to reduced inflammation and improved insulin sensitivity in T2DM rats.

Research progress in functional polarization of tumor-associated macrophages and targeting strategies / 中华微生物学和免疫学杂志

Tumor-associated macrophages (TAMs) are the predominant immune cells in the tumor microenvironment (TME). They have been shown to play an important immunosuppressive role in the development of TME and promote tumor immune escape, growth and metastasis. It is a current research hotspot to regulate the functional polarization of TAMs through trained immunity (metabolic reprogramming, epigenetic remodeling) to affect the occurrence and development of tumors. Therefore, in-depth research in this field not only presents a more comprehensive perspective on the pathogenesis of immune-mediated diseases, but also can provide new strategies for clinical anti-tumor immunotherapy. This paper outlines the origin of TAMs and the phenotypes and mechanisms of TAMs polarization, discusses the mechanisms by which metabolic reprogramming and epigenetic remodeling regulate TAMs, summarizes the regulation of TAMs activation and polarization by them, and provides an overview of the progress in TAMs at the current stage of clinical practice, hoping to provide reference for the development of new immunoprevention and treatment strategies.

Mechanism of Huangwu Ganfu Ointment in Treatment of Peripheral Inflammatory Hyperalgesia of Knee Osteoarthritis Based on TRPV1 / 中国实验方剂学杂志

ObjectiveTo observe the regulatory effect of Huangwu Ganfu ointment on transient receptor potential anchor protein 1 （TRPV1） receptor expression， macrophage polarization， and p38 mitogen-activated protein kinase （p38 MAPK） signaling pathway in synovial tissue of knee osteoarthritis （KOA） rats with yang deficiency and cold coagulation syndrome and explore the mechanism of relieving peripheral inflammatory hyperalgesia of KOA. MethodForty-eight male SD rats were randomly divided into blank group， model group， high-dose， middle-dose， and low-dose groups of Huangwu Ganfu ointment （9.3， 4.65， 2.325 g·kg-1）， and celecoxib group （20.82 mg·kg-1）. The KOA rat model of yang deficiency and cold coagulation syndrome was established through climate box and swimming for two weeks combined with an injection of sodium iodoacetate （MIA） in the articular cavity. After continuous administration for four weeks， the general condition of rats in each group was observed， and the pain withdrawal threshold （PWT） and joint diameter induced by mechanical stimulation were recorded. The expression levels of interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， nerve growth factor （NGF）， and calcitonin gene-related peptide （CGRP） inflammatory factor were detected by enzyme-linked immunosorbent assay （ELISA）， and the histopathological changes of synovial tissue of the knee joint were observed by hematoxylin-eosin （HE） staining. Western blot was used to detect the protein expression of TRPV1， p38 MAPK， and p-p38 MAPK in synovial tissue of the knee joint， and immunofluorescence （IF） was used to evaluate the polarization of M1/M2 macrophages. ResultCompared with that in the blank group， the overall mental state of the model group was worse， and the autonomous activity was decreased. The body mass was lower， and the joint diameter was increased. The X-ray showed that the osteophyte at the edge of the joint proliferated， and the articular surface was obviously rough. The articular cavity was significantly narrowed， and the PWT was significantly decreased （P<0.01）. The contents of IL-1β， TNF-α， CGRP， and NGF in serum and synovium Krenn score increased significantly （P<0.01）. The protein expression of TRPV1 and p-p38 MAPK/p38 MAPK increased significantly （P<0.01）， and the proportion of M1 macrophages and M1/M2 increased （P<0.01）， while the proportion of M2 macrophages decreased （P<0.01）. Compared with model group， the body mass in the low， middle， and high dose groups of Huangwu Ganfu ointment increased to different degrees （P<0.05， P<0.01）. The diameter of the knee joint in the high dose group of Huangwu Ganfu ointment and celecoxib group decreased （P<0.01）. The recovery of PWT in the high and middle dose groups of Huangwu Ganfu ointment groups was more obvious （P<0.05）. The contents of IL-1β and CGRP in the serum of rats in each administration group were significantly decreased （P<0.01）， and the content of serum TNF-α in the celecoxib group and high dose group of Huangwu Ganfu ointment decreased significantly （P<0.05）. The content of serum NGF in the middle dose group of Huangwu Ganfu ointment decreased significantly （P<0.05）， and the synovium Krenn score decreased in the high dose group of Huangwu Ganfu ointment （P<0.05）. In addition， the protein expression of TRPV1 and p-p38 MAPK/p38 MAPK in synovial tissue decreased significantly in all groups of Huangwu Ganfu ointment （P<0.01）. The proportion of M1 macrophages in synovial tissue in the celecoxib group and all groups of Huangwu Ganfu ointment decreased （P<0.01）， and the proportion of M2 macrophages in the high dose group of Huangwu Ganfu ointment increased （P<0.05）. The M1/M2 in the middle and high dose groups of Huangwu Ganfu ointment decreased （P<0.05）. ConclusionHuangwu Ganfu ointment can mediate the polarization of macrophages to reduce the inflammatory reaction of KOA， alleviate the release of inflammatory pain mediators， and lower the protein expression of TRPV1. The mechanism may be related to the p38 MAPK signaling pathway， so as to improve the peripheral hyperalgesia of KOA.