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.

Pathogenesis of Idiopathic Pulmonary Fibrosis and Modulating Effect of Chinese Medicine： A Review / 中国实验方剂学杂志

Idiopathic pulmonary fibrosis （IPF）， as a progressive lung disease， has a poor prognosis and no reliable and effective therapies. IPF is mainly treated by organ transplantation and administration of chemical drugs， which are ineffective and induce side effects， failing to meet the clinical needs. Therefore， developing safer and more effective drugs has become an urgent task， which necessitates clear understanding of the pathogenesis of IPF. The available studies about the pathogenesis of IPF mainly focus on macrophage polarization， epithelial-mesenchymal transition （EMT）， oxidative stress， and autophagy， while few studies systematically explain the principles and links of the pathogeneses. According to the traditional Chinese medicine theory， Qi deficiency and blood stasis and Qi-Yang deficiency are the key pathogeneses of IPF. Therefore， the Chinese medicines or compound prescriptions with the effects of replenishing Qi and activating blood， warming Yang and tonifying Qi， and eliminating stasis and resolving phlegm are often used to treat IPF. Modern pharmacological studies have shown that such medicines play a positive role in inhibiting macrophage polarization， restoring redox balance， inhibiting EMT， and regulating cell autophagy. However， few studies report how Chinese medicines regulate the pathways in the treatment of IPF. By reviewing the latest articles in this field， we elaborate on the pathogenesis of IPF and provide a comprehensive overview of the mechanism of the active ingredients or compound prescriptions of Chinese medicines in regulating IPF. Combining the pathogenesis of IPF with the modulating effects of Chinese medicines， we focus on exploring systemic treatment options for IPF， with a view to providing new ideas for the in-depth study of IPF and the research and development of related drugs.

Role of Macrophage Polarization in Chronic Low-grade Inflammation of PCOS Based on Theory of Spleen Being in Charge of Defensive Function / 中国实验方剂学杂志

Polycystic ovary syndrome （PCOS） is a reproductive endocrine disorder characterized by coexisting reproductive dysfunction and glucolipid metabolic disturbance， affecting 8%-13% of women of reproductive age and 3%-11% of adolescent females. Due to the highly heterogeneous clinical features， symptom-oriented individualized strategies are commonly adopted for the treatment of PCOS. Chronic low-grade inflammation is one of the core mechanisms for the occurrence of PCOS. Macrophages， as foundational cells of innate immunity， play an indispensable role in modulating systemic inflammatory responses. The imbalance of macrophage M1/M2 polarization is involved in chronic low-grade inflammation in PCOS via pathways such as activating pro-inflammatory responses， disrupting ovarian tissue repair， stimulating excessive synthesis of androgens， and promoting the occurrence of insulin resistance. Reshaping the phenotype of macrophages might serve as a potential therapeutic strategy for PCOS. Traditional Chinese medicine （TCM） holds that spleen deficiency and phlegm dampness is a crucial pathogenesis of PCOS. The spleen， being in charge of defensive function， plays a key role in ensuring normal physiological functions such as transportation and defense against external pathogen during the occurrence and development of PCOS. The imbalance of macrophage polarization resembles the transition from spleen being in charge of defensive function to spleen losing its defensive role in TCM. Therefore， this paper， for the first time， explores the deep connection between macrophage polarization and the pathogenesis of chronic low-grade inflammation in PCOS from the TCM theory of spleen being in charge of defensive function， providing theoretical support and new research directions for the treatment and drug research of PCOS.

Hydrogen therapy promotes macrophage polarization to the M2 subtype by inhibiting the NF-κB signaling pathway / 中国辐射卫生

Objective To investigate the role of hydrogen therapy in reducing radiation-induced lung injury and the specific mechanism. Methods Forty C57BL/6 mice were randomly divided into four groups: normal control group, model group, hydrogen therapy group I, and hydrogen therapy group II. A mouse model of radiation-induced lung injury was established. The pathological changes in the lung tissue of the mice were examined with HE staining. Immunofluorescence staining was used to detect the expression of surface markers of M1 and M2 macrophages to observe macrophage polarization. The expression of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and IL-10 in the lung tissue was measured by immunohistochemistry. The expression of nuclear factor-kappa B (NF-κB) p65 and phosphorylated NF-κB (P-NF-κB) p65 was measured by Western blot. Results HE staining showed that compared with the control group, the model group exhibited alveolar septal swelling and thickening, vascular dilatation and congestion, and inflammatory cell infiltration in the lung tissue; the hydrogen groups had significantly reduced pathological damage and inflammatory response than the model group, with more improvements in hydrogen group II than in hydrogen group I. Immunohistochemical results showed that compared with those in the control group, the levels of the inflammatory cytokines IL-6 and TNF-α were significantly increased in the model group; the hydrogen groups showed significantly decreased IL-6 and TNF-α levels and a significantly increased level of the anti-inflammatory factor IL-10 than the model group, which were more marked in hydrogen group II than in hydrogen group I. Immunofluorescence results showed that compared with the control group, the expression of the surface marker of M1 macrophages in the model group was significantly upregulated; the hydrogen groups showed significantly downregulated M1 marker and significantly upregulated M2 marker, and hydrogen group II showed significantly increased M2 marker compared with hydrogen group I. Western blot results showed that compared with that in the control group, the ratio of P-NF-κB p65/NF-κB p65 in the model group was significantly increased; the P-NF-κB p65/NF-κB p65 ratio was significantly reduced in the hydrogen groups than in the model group, and was significantly lower in hydrogen group II than in hydrogen group I. Conclusion Hydrogen inhalation therapy may reduce the inflammatory response of radiation-induced lung injury by inhibiting the NF-κB signaling pathway to promote the polarization of the macrophage M1 subtype to the M2 subtype.

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.

Treatment of Inflammatory Bowel Disease by Targeting M1/M2 Macrophage Polarization Balance with Traditional Chinese Medicine and Active Components： A Review / 中国实验方剂学杂志

Inflammatory bowel disease （IBD）， consisting of ulcerative colitis and Crohn's disease， is a chronic relapsing inflammatory gastrointestinal disease closely associated with immune dysfunction. The pathogenesis of IBD is closely related to genetic susceptibility， immune system dysfunction， environmental change， and intestinal microbial dysbiosis. Modern research has found that macrophage polarization plays an important role in the development of IBD and can affect the level of inflammatory response， intestinal mucosal repair， and intestinal microbial balance， making it a potential target for IBD treatment. Increasing evidence suggests that traditional Chinese medicine and its active components can regulate macrophage polarization through multiple pathways and balance the M1/M2 macrophage ratio， thus inhibiting inflammatory response， promoting intestinal mucosal repair， and slowing down the progression of IBD. This article summarized the biological processes and targets involved in macrophage polarization and discussed its impact on IBD. It also provided a brief overview of the latest research on how traditional Chinese medicine and its active components can improve IBD by regulating macrophage polarization， so as to provide new directions and strategies for the clinical application of traditional Chinese medicine in IBD treatment.

Advances in Mechanotransduction Pathway of Macrophage / 医用生物力学

Mechanical stimulation in micro-environment ( such as matrix stiffness, surface topography, cyclical stretch) can be perceived by macrophages through receptors on cell membrane, transmitted to the nucleus along the adhesion protein molecular chain and cytoskeleton, and also converted into biochemical signal to stimulate gene transcription. Mechanical stimulation drives various biological functions in macrophages, such as adhesion, proliferation, migration, and polarization, thereby playing a corresponding role in disease progression and tissue regeneration. This study demonstrates the role of micro-environment mechanics in macrophages polarization and function, and elucidates the related mechanism of mechanotransduction pathway in macrophages, so as to provide molecular biomechanics insights into the development of macrophage-targeting immunomodulatorybiomaterials.

Akt2 inhibitor promotes M2 macrophage polarization in rats with periapical inflammation by reducing miR-155-5p expression / 南方医科大学学报

OBJECTIVE@#To investigate the effect of Akt2 inhibitor on macrophage polarization in the periapical tissue in a rat model of periapical inflammation.@*METHODS@#Rat models of periapical inflammation were established in 28 normal SD rats by opening the pulp cavity of the mandibular first molars, followed by injection of normal saline and Akt2 inhibitor into the left and right medullary cavities, respectively. Four rats without any treatment served as the healthy control group. At 7, 14, 21 and 28 days after modeling, 7 rat models and 1 control rat were randomly selected for observation of inflammatory infiltration in the periapical tissues by X-ray and HE staining. Immunohistochemistry was used to detect the expression and localization of Akt2, macrophages and the inflammatory mediators. RT-PCR was performed to detect the mRNA expressions of Akt2, CD86, CD163, inflammatory mediators, miR-155-5p and C/EBPβ to analyze the changes in macrophage polarization.@*RESULTS@#X-ray and HE staining showed that periapical inflammation was the most obvious at 21 days after modeling in the rats. Immunohistochemistry and RT-PCR showed that compared with those in the control rats, the expressions of Akt2, CD86, CD163, miR-155-5p, C/EBPβ, and IL-10 increased significantly in the rat models at 21 days (P < 0.05). Compared with saline treatment, treatment with the Akt2 inhibitor significantly decreased the expression levels of Akt2, CD86, miR-155-5p and IL-6 and the ratio of CD86+M1/CD163+M2 macrophages (P < 0.05) and increased the expression levels of CD163, C/EBPβ and IL-10 in the rat models (P < 0.05).@*CONCLUSION@#Inhibition of Akt2 can delay the progression of periapical inflammation in rats and promote M2 macrophage polarization in the periapical inflammatory microenvironment possibly by reducing miR-155-5p expression and activating the expression of C/EBPβ in the Akt signaling pathway.

Effect of Fangji Fulingtang on Macrophage Polarization and Oxidative Stress in Mouse Model of Myocardial Fibrosis / 中国实验方剂学杂志

ObjectiveTo investigate the effects of Fangji Fulingtang on macrophage polarization and oxidative stress in the mouse model of myocardial fibrosis. MethodThe mouse model of myocardial fibrosis was established by subcutaneous injection of isoproterenol （ISO， 5 mg·kg-1·d-1）. Fifty C57BL/6J mice were randomly assigned into control （0.9% NaCl）， model （0.9% NaCl）， low- and high-dose （3.315 g·kg-1·d-1 and 13.26 g·kg-1·d-1， respectively） Fangji Fulingtang （FFD-L and FFD-H， respectively）， and metoprolol tartrate （Meto， 15 mg·kg-1·d-1） groups， with 10 mice each group. After 2 weeks of treatment， the heart appearance， cardiac weight index （CWI）， heart weight （HW）/tibia length （TL） ratio， and myocardial histopathological alterations were observed. Meanwhile， the serum levels of creatine kinase-MB （CK-MB）， transforming growth factor-β1 （TGF-β1）， tumor necrosis factor-α （TNF-α）， interleukin （IL）-1β， IL-6， IL-10， malondialdehyde （MDA）， superoxide dismutase （SOD）， and glutathione （GSH） were measured by enzyme-linked immunosorbent assay （ELISA）. The expression levels of CD86 and CD206 were observed by immunohistochemical staining. ResultCompared with the model group， the FFD-L， FFD-H， and Meto groups showed improved heart appearance， decreased CWI and HW/TL ratio （P<0.01）， lowered serum levels of CK-MB， TGF-β1， TNF-α， IL-1β， and IL-6 （P<0.05， P<0.01）， and elevated IL-10 level （P<0.05）. Furthermore， the three groups showed reduced infiltration of inflammatory cells， myocardial injury， collagen deposition， and myocardial fibrosis， decreased CD86， SOD， and GSH （P<0.01）， and increased CD206 and MDA （P<0.01）. ConclusionFangji Fulingtang can mitigate ISO-induced myocardial fibrosis by regulating macrophage polarization and oxidative stress.

Research progress of macrophage polarization in the treatment of aortic dissection / 中国胸心血管外科临床杂志

@#Aortic dissection is one of the most devastating cardiovascular diseases. One of the most important pathological features of aortic dissection is local inflammatory response, including the infiltration of inflammatory cells, extracellular matrix degradation, and smooth muscle cell phenotype switch. Macrophages which are the core of the inflammatory response play an extremely pivotal role in the progression of inflammation and tissue remodeling. Macrophages can be artificially divided into M1 and M2 types, of which the M1-type promotes inflammation while the M2-type is associated with the regression of inflammation and tissue healing. Mastering the switch of phenotypic transformation of macrophages may be of great help in inhibiting the inflammation of aortic tissue and facilitating tissue healing, as well as the treatment of aortic dissection. In this paper, we focus on the polarization of macrophages and discuss the role of macrophages in aortic dissection, the polarization pathway and the effect of related polarizing agents on the treatment of aortic dissection.

Analysis of Mechanism of Qinggan Jianpi Huoxue Prescription in Treatment of Hepatic Fibrosis Rats by Regulating M1/M2 Macrophages / 中国实验方剂学杂志

ObjectiveTo observe the effect of Qinggan Jianpi Huoxue prescription（QGJPHXP） on the polarization of M1/M2 macrophages in rats with hepatic fibrosis induced by carbon tetrachloride（CCl4）. MethodA rat hepatic fibrosis model was established by intraperitoneal injection of 40% CCl4-olive oil suspension twice a week at the dosage of 2.0 mL·kg-1 for 8 weeks. After the model was successfully established， these rats were randomly divided into the model group， QGJPHXP group（32.084 g·kg-1） and Biejiajian pills（BJJP） group（0.925 5 g·kg-1）， with 12 rats in each group. The blank group was injected intraperitoneally with the same amount of olive oil. The rats in the administration groups were given the corresponding solution according to the dose， and the blank and model groups were given the same dose of purified water， once a day. After 4 weeks of continuous administration， the liver tissues of rats were taken and stained with hematoxylin-eosin（HE） and Masson to observe the pathological changes. The serums were collected to detect the alanine aminotransferase（ALT） and aspartate aminotransferase（AST） levels. Interleukin（IL）-6， IL-12， IL-10， IL-1β， transforming growth factor-β1（TGF-β1） and tumor necrosis factor-α（TNF-α） levels in liver tissues were measured by enzyme-linked immunosorbent assay（ELISA）. The expression levels of CD86 and CD206 were detected by immunohistochemistry（IHC）. Western blot and real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） were used to detect the protein and mRNA expression levels of inducible nitric oxide synthase（iNOS）， arginase-1（Arg-1）， phosphorylated p38 mitogen-activated protein kinase（p-p38 MAPK）， nuclear transcription factor-κB p65（NF-κB p65） in liver tissues of rats. ResultCompared with the blank group， the hepatic cell plate was irregularly arranged, and local inflammatory cell infiltration and fibrous hyperplasia were observed， while the serum levels of ALT and AST were significantly increased in the model group（P<0.01）， and IL-1β， IL-6， IL-12， TGF-β1， TNF-α， CD86， CD206， iNOS， p-p38 MAPK，p38 MAPK and NF-κB p65 levels in liver tissues were obviously increased（P<0.05， P<0.01）， while the levels of IL-10 and Arg-1 were obviously decreased（P<0.05， P<0.01）. Compared with the model group， QGJPHXP group reduced the degree of liver cell fibrosis，and serum levels of ALT and AST（P<0.01）， and IL-1β， IL-6， IL-12， TGF-β1， TNF-α， CD86， iNOS， p-p38 MAPK， p38 MAPK， and NF-κB p65 levels in liver tissues were obviously decreased（P<0.05， P<0.01）， the levels of IL-10， CD206 and Arg-1 were obviously increased in the QGJPHXP group（P<0.05， P<0.01）. ConclusionQGJPHXP has ability to inhibit the activation of pro-inflammatory M1 macrophages， induce the secretion of anti-inflammatory cytokines by M2 macrophages， reduce the release of pro-fibrogenic cytokines， and promote the macrophage polarization of M1 to M2 in liver for tissue repair， thereby serving as an anti-inflammatory and anti-hepatic fibrosis drug.

Regulation of palmitic acid and lipopolysaccharide-induced macrophage polarization by adipokine WNT1-inducible signaling pathway protein 2 / 中华老年医学杂志

Objective:To investigate the regulatory effect of WNT1-inducible signaling pathway protein 2(WISP2)on macrophage polarization in palmitic acid(PA)and lipopolysaccharide(LPS)-induced inflammation.Methods:The macrophage cell line RAW264.7 was treated with different concentrations of WISP2 protein, and cell viability was determined by means of luminescence assay using Cell-Titer Glo to determine the concentration of WISP2.The cells were divided into control group, palmitic acid group, palmitic acid combined with different concentrations of WISP2 group(10 μg/L and 100 μg/L)and lipopolysaccharide group, lipopolysaccharide combined with different concentrations of WISP2 group(10 μg/L and 100 μg/L). mRNA expression of M1 and M2 macrophages phenotype of each group were detected by real-time quantitative polymerase chain reaction.The protein expression of important inflammatory factors, TNF-α and IL-6, were evaluated by ELISA.Results:Compared with the control group, both 10 μg/L and 100 μg/L WISP2 groups had no effect on the activity of RAW264.7 cells, but significantly up-regulated the expression of various inflammatory factors, including Tnfα(1.877±0.039, 2.202±0.034, F=309.7, P<0.001), Il6(1.418±0.056, 1.506±0.059, F=81.39, P<0.001), Mcp1(1.620±0.014, 1.982±0.125, F=71.45, P<0.001), Ccl3(1.892±0.118, 1.942±0.132, F=32.93, P<0.001), and iNos(1.691±0.201, 1.548±0.090, F=13.60, P<0.05). mRNA in macrophages, and significantly down-regulated the expression of anti-inflammatory factors, including Tgfβ(1.376±0.025, 2.152±0.107, F=1.846, P<0.05), CD206(2.123±0.031, 3.139±1.663, F=8.037, P<0.05), Il4(2.098±0.464, 2.494±0.141, F=48.68, P<0.01), and Il10(1.303±0.216, 1.574±0.274, F=5.774, P<0.05)mRNA, causing M1 type macrophage polarization.Compared with the control group, 100 μmol/L palmitic acid could mildly but significantly increase the expression of inflammatory factors such as TNF-α and IL-6 at the transcriptional and protein levels.Compared with palmitic acid stimulation alone, the combination of palmitic acid and WISP2 further promoted the protein expression of macrophage inflammatory factors TNF-α[(589.4±17.0)ng/L, (692.6±83.4)ng/L, F=56.38, P<0.05], IL-6[(15.13±1.14)ng/L, (13.33±1.22)ng/L, F=23.32, P<0.001]and the mRNA expression of chemokines Mcp1(160±9.796, 140±18.91, F=141.1, P<0.0001)and C cl3(17.76±1.92, 14.41±1.27, F=125.2, P<0.0001). Compared with the control group, 100 μg/L lipopolysaccharide strongly stimulated the expression of inflammatory factors such as TNF-α[(3444±423)ng/L, F=71.20, P<0.0001]and IL-6[(497.0±41.2)ng/L, F=63.50, P<0.0001]in macrophages at the protein level.Compared with lipopolysaccharide stimulation alone, the combination of lipopolysaccharide and WISP2 further significantly up-regulated the mRNA expression of chemokines Mcp1(106.8±8.7, 118.7±4.6, F=251.5, P<0.0001)and Ccl3(35.3±12.5, 116.4±4.5, F=160.1, P<0.0001). Conclusions:The adipokine WISP2 can promote M1 macrophage polarization in palmitic acid and lipopolysaccharide-induced inflammation, and it had distinct regulation in macrophage polarization under different inflammatory response conditions.

Prophylactic Vitamin C Attenuates Radiation-induced Lung Injury by Modulating Macrophage Polarization and Alveolar Epithelial Cell Apoptosis / 中国生物化学与分子生物学报

With the ongoing epidemic of the Coronavirus disease in China and the widespread development of radiotherapy, radiation-induced lung injury has gradually become a clinical problem that has attracted much attention. The pathogenesis of radiation-induced lung injury is complex, involving an imbalance in the polarization state of alveolar macrophages and an upregulation of alveolar epithelial cell apoptosis. Previous studies have shown that vitamin C is an important antioxidant substance, and preventive use of vitamin C can effectively treat acute lung injury. However, whether prophylactic use of vitamin C can effectively prevent or treat lung injury caused by radioactive substances, and its specific molecular mechanism remains to be studied. The purpose of this study is to investigate whether the prophylactic use of vitamin C to treat the alveolar macrophage cell line RAW 264. 7 and human lung epithelial cells BEAS-2B can effectively control the abnormal polarization of macrophages and the abnormal apoptosis of lung epithelial cells. This study found that after 4 weeks and 8 weeks of radioactive X-ray irradiation, the expression of macrophage M1 polarization state markers such as iNOS was significantly up-regulated (P< 0. 05), and preventive use of vitamin C to treat macrophages and lung epithelial cells can alleviate the polarization state disorder of macrophages and the apoptosis of alveolar epithelial cells caused by external radiation exposure, which is manifested in the down-regulation of the expression of Cleaved Caspase3. In addition, the preventive application of vitamin C treatment can inhibit the MAPK signaling pathway activated by external radiation exposure. Further experimental results showed that the inhibition of the MAPK pathway is the key to inhibiting the M1 polarization of macrophages and the apoptosis of lung epithelial cells. In summary, our findings suggest that vitamin C may play a protective role in acute radiation-induced lung injury by inhibiting macrophage M1 polarization/ promoting macrophage M2 polarization and alleviating alveolar epithelial cell apoptosis. This study will help to better understand the process and mechanism of the preventive effect of vitamin C, a common vitamin, on radiation-induced lung injury.

Preliminary study on the effect of Echinococcus multilocaris on phenotypic transformations of glucose metabolism and polarization types in macrophages / 中国血吸虫病防治杂志

Objective To investigate the effects of Echinococcus multilocularis on the phenotypic transformations of glucose metabolism, polarization types and inflammatory responses in macrophages, so as to provide insights into elucidation of echinococcosis pathogenesis. Methods Bone marrow cells were isolated from C57BL/6J mice at ages of 6 to 8 weeks, and induced into bone marrow-derived macrophages (BMDMs) with mouse macrophage colony-stimulating factor (M-CSF), which served as controls (BMDMs-M0). BMDMs-M0 induced M2 macrophages by interleukin-4 for 24 hours served as the IL-4 induction group, and BMDMs-M0 co-cultured with 2.4 ng/mL E. multilocularis cystic fluid (CF) served as the BMDM-CF co-culture group, while BMDMs-M0 co-cultured with E. multilocularis protoscolex (PSC) at a ratio of 500:1 served as the BMDM-PSC co-culture group. The types of polarization of BMDMs co-cultured with E. multilocularis CF and PSC were analyzed using flow cytometry, and the expression of macrophage markers, inflammatory factors, and glucose metabolism-related enzymes was quantified using fluorescent quantitative real-time PCR (qPCR) and Western blotting assays. Results There were significant differences among the four groups in terms of Arginase-1 (Arg1) (F = 1 457.00, P < 0.000 1), macrophages-derived C-C motif chemokine 22 (Ccl22) (F = 22 203.00, P < 0.000 1), resistin-like α (Retnla) (F = 151.90, P < 0.000 1), inducible nitric oxide synthase (iNOS) (F = 107.80, P < 0.001), hexokinase (HK) (F = 9 389.00, P < 0.000 1), pyruvate kinase (PK) (F = 641.40, P < 0.001), phosphofructokinase 1 (PFK1) (F = 43.97, P < 0.01), glucokinase (GK) (F = 432.50, P < 0.000 1), pyruvate dehydrogenase kinases1 (PDK1) (F = 737.30, P < 0.000 1), lactic dehydrogenase (LDH) (F = 3 632.00, P < 0.000 1), glucose transporter 1 (GLUT1) (F = 532.40, P < 0.000 1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) (F = 460.00, P < 0.000 1), citrate synthase (CS) (F = 5 642.00, P < 0.01), glycogen synthase1 (GYS1) (F = 273.30, P < 0.000 1), IL-6 (F = 1 823.00, P < 0.000 1), IL-10 (F = 291.70, P < 0.000 1), IL-1β (F = 986.60, P < 0.000 1), and tumor necrosis factor (TNF)-α (F = 334.80, P < 0.000 1) and transforming growth factor (TGF)-β mRNA expression (F = 163.30, P < 0.001). The proportion of M2 macrophages was significantly higher than that of M1 macrophages in the BMDM-PSC co-culture group [(22.87% ±1.48%) vs. (1.70% ±0.17%); t = 24.61, P < 0.001], and the proportion of M2 macrophages was significantly higher than that of M1 macrophages in the BMDM-CF co-culture group [(20.07% ±0.64%) vs. (1.93% ±0.25%); t = 45.73, P < 0.001]. The mRNA expression of M2 macrophages markers Arg1, Ccl22 and Retnla was significantly higher in the BMDM-CF and BMDM-PSC co-culture groups than in the control group (all P values < 0.01), and no significant difference was seen in the mRNA expression of the M1 macrophage marker iNOS among the three groups (P > 0.05), while qPCR assay quantified higher mRNA expression of key glycolytic enzymes HK, PK and PFK, as well as inflammatory factors IL-10, IL-1β, TNF-α and TGF-β in the BMDM-CF and BMDM-PSC co-culture groups than in the control group (all P values < 0.01). Western blotting assay determined higher HK, PK and PFK protein expression in the BMDM-PSC co-culture group than in the control group (all P values < 0.05), and qPCR quantified higher GLUT1, GAPDH and IL-6 mRNA expression in the BMDM-CF co-culture group than in the control group (all P values < 0.05), while higher HK, PK and PFK protein and mRNA expression (all P values < 0.01), as well as lower IL-6 and TNF-α and higher TGF-β mRNA expression (both P values < 0.05) was detected in the IL-4 induction group than in the control group. Glycolytic stress test showed no significant difference in the extracellular acidification rate (ECAR) of mouse BMDM among the control group, IL-4 induction group and BMDM-PSC co-culture group (F = 124.4, P < 0.05), and a higher ECAR was seen in the BMDM-PSC co-culture group and a lower ECAR was found in the IL-4 induction group than in the control group (both P values < 0.05). Conclusions Treatment of E. multilocularis CF or PSC mainly causes polarization of BMDM into M2 macrophages, and phenotypic transformation of glucose metabolism into high-energy and high-glycolytic metabolism, and affects inflammatory responses in BMDM.

Purpurolide C-based microneedle promotes macrophage-mediated diabetic wound healing via inhibiting TLR4-MD2 dimerization and MYD88 phosphorylation

Delayed wound healing in diabetes is a global challenge, and the development of related drugs is a clinical problem to be solved. In this study, purpurolide C (PC), a small-molecule secondary metabolite of the endophytic fungus Penicillium purpurogenum, was found to promote diabetic wound healing. To investigate the key regulation targets of PC, in vitro RNA-seq, molecular docking calculations, TLR4-MD2 dimerization SDS-PAGE detection, and surface plasmon resonance (SPR) were performed, indicating that PC inhibited inflammatory macrophage activation by inhibiting both TLR4-MD2 dimerization and MYD88 phosphorylation. Tlr4 knockout in vivo attenuated the promotion effect of PC on wound healing. Furthermore, a delivery system consisting of macrophage liposome and GelMA-based microneedle patches combined with PC (PC@MLIP MN) was developed, which overcame the poor water solubility and weak skin permeability of PC, so that successfully punctured the skin and delivered PC to local tissues, and accurately regulated macrophage polarization in diabetic wound management. Overall, PC is an anti-inflammatory small molecule compound with a well-defined structure and dual-target regulation, and the PC@MLIP MN is a promising novel biomaterial for the management of diabetic wound.

An injectable bioactive dressing based on platelet-rich plasma and nanoclay: Sustained release of deferoxamine to accelerate chronic wound healing

Delayed diabetic wound healing has placed an enormous burden on society. The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis. Platelet-rich plasma (PRP) gel, a popular biomaterial in the field of regeneration, has limited applications due to its non-injectable properties and rapid release and degradation of growth factors. Here, we prepared an injectable hydrogel (DPLG) based on PRP and laponite by a simple one-step mixing method. Taking advantages of the non-covalent interactions, DPLG could overcome the limitations of PRP gels, which is injectable to fill irregular injures and could serve as a local drug reservoir to achieve the sustained release of growth factors in PRP and deferoxamine (an angiogenesis promoter). DPLG has an excellent ability in accelerating wound healing by promoting macrophage polarization and angiogenesis in a full-thickness skin defect model in type I diabetic rats and normal rats. Taken together, this study may provide the ingenious and simple bioactive wound dressing with a superior ability to promote wound healing.

Discovery of novel aporphine alkaloid derivative as potent TLR2 antagonist reversing macrophage polarization and neutrophil infiltration against acute inflammation

Toll-like receptor 2 (TLR2) mediated macrophages regulate the protective immune response to infectious microorganisms, but the aberrant activation of macrophages often leads to pathological inflammation, including tissue damage. In this study, we identified antagonists of TLR2 by screening 2100 natural products and subsequently identified Taspine, an aporphine alkaloid, as an excellent candidate. Furthermore, analysis of the 10 steps chemical synthesis route and structural optimization yielded the Taspine derivative SMU-Y6, which has higher activity, better solubility, and improved drug-feasible property. Mechanistic studies and seq-RNA analysis revealed that SMU-Y6 inhibited TLR2 over other TLRs, hindered the formation of TLR2/MyD88 complex, and blocked the downstream NF-κB and MAPK signaling pathway, thus suppressing the release of inflammatory cytokines. SMU-Y6 could stabilize TLR2 and bind to TLR2 protein with a Kd of 0.18 μmol/L. Additionally, SMU-Y6 could efficiently reverse the M1 phenotype macrophage polarization, reduce the production of cytokines as well as infiltration of neutrophiles and alleviate the local inflammation in mice with acute paw edema and colitis. Collectively, we reported the first aporphine alkaloid derivative that selectively inhibits TLR2 with high binding affinity and superior drug-feasible property, thus providing an urgently-needed molecular probe and potential drug candidate for inflammatory and autoimmune disease therapy.

Evolution of Research Related to Macrophage Polarization in Atherosclerosis:A Visualization Analysis / 中国医学科学院学报

Objective To explore the research status,hotspots,and development tendency of macrophage polarization (MP) in atherosclerosis (AS) by systematically reviewing and visually analyzing the articles published recently in this field,so as to provide new ideas for the basic research and translational research on MP in the prevention and treatment of AS.Methods SCI-Expanded was used as the data source for the retrieval of the articles involving MP in AS from 2012 to 2022.CiteSpace 6.1.R3 was employed to visualize the node information of the publishing country/region,institutions,authors,keywords,and citations.Results A total of 381 papers were included.The number of publications in the world showed an increasing trend year by year.China and the United States were leading this field in the number and centrality of publications,and Shandong University in China contributed the largest number of publications.The analysis of the key words and citations showed that the hotspots and frontiers in this field mainly included the pathogenesis of AS,MP markers,macrophage plasticity regulation,and potential therapeutic targets for AS.Conclusions The research on MP in AS was booming during 2012-2022.The differential gene expression and the molecular mechanism of targeted therapy of MP in AS are the research trends in this field,which will provide new measures for the prevention and treatment of AS.

Short-term medication of dapagliflozin exacerbates CCl4 induced acute liver injury / 西安交通大学学报(医学版)

【Objective】 To investigate the role and mechanism of dapagliflozin (Dapa), a sodium glucose co-transporter 2 inhibitor, in acute liver injury. 【Methods】 Eight-week-old C57BL6/J mice were given a single intraperitoneal injection of CCl4 to induce acute liver injury. The mice were preventively given 5 mg/kg Dapa by gavage 24 h and 2 h before CCl4 injection, while those in the control group were given an equal volume of solvent gavage. After 24 h, the mice were anesthetized and sacrificed. H&E staining, plasma biochemistry, RT-qPCR, and Western blotting were used to detect the severity of liver injury and the expressions of macrophage-related genes. 【Results】 In the CCl4 group, hepatic infiltration of inflammatory cells increased, and liver and renal functions significantly deteriorated, which was further aggravated by Dapa. CCl4 could promote the expressions of M1 macrophages and fibrosis-related genes in the liver, but reduce those of M2 and antioxidant-related genes, and the latter was further inhibited by Dapa. In addition, the protein expression of arginase 1 decreased and that of SGLT2 increased after Dapa intervention, while NF-κB pathway did not change significantly, suggesting that Dapa might directly affect the energy metabolism homeostasis in the liver and aggravate acute liver injury induced by CCl4. 【Conclusion】 Dapa can exacerbate hepatic and renal damage in acute stage of liver injury, inhibit macrophages M2 polarization, and aggravate oxidative stress and inflammatory injury induced by CCl4.

Platelet-rich Plasma Induces M2 Macrophage Polarization via Regulating AMPK Singling Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the role of platelet-rich plasma (PRP) in inducing the M2 macrophage polarization via regulating AMPK singling pathway.@*METHODS@#The expressions of M1 marker CD11c and M2 marker CD206 in macrophages of blank control group, LPS group, LPS+PRP group, and LPS+PRP+Compound C group were detected by flow cytometry. Western blot was used to observe the effects of PRP on the expression of AMPK-mTOR signaling pathway-related proteins at different times (12 h, 18 h and 24 h) after LPS treatment. RNA interference technology was used to silence the expression of AMPK in macrophages, and the expression of TGF-β protein was subsequently examined by Western blot.@*RESULTS@#LPS significantly reduced the expression of CD206 and increased the expression of CD11c (P <0.05). After the addition of PRP, the expression of CD206 was significantly increased (P <0.05), while the expression of CD11c was significantly decreased (P <0.05). Compared with LPS group, PRP treatment significantly increased the expressions of p-AMPK and p-ULK1 proteins at 12 h, 18 h and 24 h, while significantly decreased the expression of p-mTOR protein (P <0.05). After the addition of AMPK inhibitor Compound C, the expression of CD206 was significantly reduced (P <0.05) and the expression of CD11c was significantly increased compared with LPS+PRP group (P <0.05). After silencing the expression of AMPK in macrophages, the promotion effect of PRP on TGF-β was significantly reduced (P <0.05).@*CONCLUSION@#PRP can stimulate the transformation of macrophages to M2 type via AMPK signalling pathway.