ObjectiveTo study the effect and mechanism of lipopolysaccharide (LPS) on osteoclasts formation and its bone resorption function.MethodsBone marrow-derived macrophages (BMMs) were extracted from the marrow of femur and tibia of 4-week-old male C57BL/6 mice. Flow cytometry was used to detect BMMs. The effect of different concentrations of LPS (0, 100, 200, 500, 1 000, 2 000 ng/mL) on BMMs activity was examined by cell counting kit 8 (CCK-8) activity test. In order to investigate the effect of LPS on osteoclastogenesis, BMMs were divided into macrophage colony-stimulating factor (M-CSF) group, M-CSF+receptor activator of nuclear factor κB ligand (RANKL) group, M-CSF+RANKL+50 ng/mL LPS group, M-CSF+RANKL+100 ng/mL LPS group. After the completion of culture, tartrate resistant acid phosphatase (TRAP) staining was used to observe the formation of osteoclasts. In order to investigate the effect of LPS on the expression of Connexin43, BMMs were divided into the control group (M-CSF+RANKL) and the LPS group (M-CSF+RANKL+100 ng/mL LPS); and the control group (M-CSF+RANKL), 50 ng/mL LPS group (M-CSF+RANKL+50 ng/mL LPS), and 100 ng/mL LPS group (M-CSF+RANKL+100 ng/mL LPS). The expressions of Connexin43 mRNA and protein were detected by Western blot and real-time fluorescent quantitative PCR, respectively. In order to investigate the effect of LPS on osteoclast bone resorption, BMMs were divided into M-CSF group, M-CSF+RANKL group, M-CSF+RANKL+50 ng/mL LPS group, and M-CSF+RANKL+100 ng/mL LPS group. Bone absorption test was used to detect the ratio of bone resorption area.ResultsThe flow cytometry test confirmed that the cultured cells were BMMs, and CCK-8 activity test proved that the 100 ng/mL LPS could promote the proliferation of BMMs, showing significant differences when compared with the 0, 200, 500, 1 000, and 2 000 ng/mL LPS (P<0.05). TRAP staining showed no osteoclast formation in M-CSF group. Compared with M-CSF+RANKL group, the osteoclasts in M-CSF+RANKL+50 ng/mL LPS group and M-CSF+RANKL+100 ng/mL LPS group were larger with more nuclei, while the osteoclasts in M-CSF+RANKL+100 ng/mL LPS group were more obvious, and the differences in the ratio of osteoclast area between groups were statistically significant (P<0.05). Western blot result showed that the relative expression of Connexin43 protein in LPS group was significantly higher than that in control group (P<0.05). Real-time fluorescent quantitative PCR showed that the relative expression of Connexin43 mRNA in control group, 50 ng/mL LPS group, and 100 ng/mL LPS group increased gradually, and the differences between groups were statistically significant (P<0.05). Bone resorption test showed that osteoclast bone resorption did not form in M-CSF group, but the ratio of bone resorption area increased gradually in M-CSF+RANKL group, M-CSF+RANKL+50 ng/mL LPS group, and M-CSF+RANKL+100 ng/mL LPS group, and the differences between groups were statistically significant (P<0.05).ConclusionLPS at concentration of 100 ng/mL can promote the expression of Connexin43, resulting in increased osteoclastogenesis and enhanced osteoclastic bone resorption.
Objective To understand the role and mechanism of tumor associated macrophages (TAM) on the occurrence and development of primary liver cancer, and its application in the treatment. MethodThe related literatures about the researches of relation between TAM and primary liver cancer at home and abroad in recent years were collected, sorted out, and made a review. Results Under different stimulating factors, TAM could be polarized to anti-tumor type 1 TAMs or tumor-promoting type 2 TAMs, and type 2 TAMs was the main part in the tumor microenvironment. Through some mechanisms such as vascularity-promoting, invasion-promoting, and immunosuppression to promote the occurrence and development of tumors, and potential treatment plans for primary liver cancer could be found by targeting TAM from different perspectives. Conclusion TAM has a wide range of effects on primary liver cancer, and their mechanisms are complex, understanding the relation between them and make an effective control of TAM could provide new therapeutic ideas and plans for clinical treatment of primary liver cancer.
Objective To review the osteoimmunomodulatory effects and related mechanisms of inorganic biomaterials in the process of bone repair. Methods A wide range of relevant domestic and foreign literature was reviewed, the characteristics of various inorganic biomaterials in the process of bone repair were summarized, and the osteoimmunomodulatory mechanism in the process of bone repair was discussed. Results Immune cells play a very important role in the dynamic balance of bone tissue. Inorganic biomaterials can directly regulate the immune cells in the body by changing their surface roughness, surface wettability, and other physical and chemical properties, constructing a suitable immune microenvironment, and then realizing dynamic regulation of bone repair. Conclusion Inorganic biomaterials are a class of biomaterials that are widely used in bone repair. Fully understanding the role of inorganic biomaterials in immunomodulation during bone repair will help to design novel bone immunomodulatory scaffolds for bone repair.
Acute pancreatitis (AP) is a gastroenterological emergency with an acute onset and a high mortality rate. The main pathogenesis of AP is pancreatic damage and excessive activation of inflammatory cells induced by multiple factors. Due to anatomical features, the liver is the first extrapancreatic organ to be attacked by high concentrations of trypsin and inflammatory mediators during AP. Hepatic macrophages have been shown to be a major source of AP-related inflammatory factors. Interventions targeting hepatic macrophages may be critical to block liver injury/failure during AP, promote tissue repair, and reduce systemic symptoms. This review summarizes the pathological role of hepatic macrophages in AP and targeted interventions to provide new ideas and approaches to resolve the pathogenesis of AP and alleviate concurrent liver injury.
ObjectiveTo compare the different effects of ubiquitin(UB) on human umbilical vein endothelial cells (HUVECs) and macrophages under normal circumstances,and analyze whether UB could protect HUVECs from lipopolysaccharide(LPS) induced injury.
MethodsThe morphologic changes of HUVECs in vitro with up-rising concentrations of UB interventions were observed. HUVECs and human macrophages in vitro were divided into 4 groups according to UB concentration (0.01 μg/mL,0.1 μg/mL, 1 μg/mL, and 10 μg/mL). Supernatant and cells of each group were collected in 24 h after UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA while NF-κB protein level in cells was detected by Western blot. HUVECs were divided into a LPS group(LPS 10 μg/mL) and an UB+LPS group(UB 0.1 μg/mL,LPS 10 μg/mL). The supernatant of the two groups were collected in 8,16 and 24 h after LPS and UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA.
ResultsThe injury of HUVECs got worse with the ascending concentrations of UB.At the concentration of 50 μg/mL,UB induced HUVECs got ballooned and died massively. With the increase of UB concentration,the levels of TNF-α and VCAM-1 in HUVECs' supernatant ascended firstly and then descended,while those in human macrophages' supernatant ascended gradually. zHowever,the tendency of the NF-κB protein level in the two kinds of cells was similar when the concentration of UB increased.At the consentration of 0.1 μg/mL or 1 μg/mL,ubiquitin induced NF-κB protein level obviously increased.At the concentration of 0.01 μg/mL or 10 μg/mL,UB induced the protein level was similar with those of the control group and even decreased slightly. There was no significant difference in TNF-α or VCAM-1 levels at each time point between the LPS group and the UB+LPS group.
ConclusionsUB injuries HUVECs obviously at a low concentration but injuires human macrophages at much higher concentraton. UB can not protect HUVECs from LPS-induced injury in vitro.
Objective To explore the association of macrophages with carcinogenesis and development of gastric cancer. Method The related literatures at home and abroad were consulted and reviewed. Results The microenvironment of gastric cancer could induce the polarization of macrophages，and then the activated macrophages，especially the tumor associated macrophages，could in turn motivate the growth，invasion，and metastasis of tumor cells by secreting a series of active substances. Conclusions Macrophages，especially the tumor associated macrophages play an importantrole in the carcinogenesis and development of gastric cancer. Investigating the macrophages and their interaction with gastric cancer may lead to a profound understanding of carcinogenesis of gastric cancer as well as opening up a new prospectfor treatment.
ObjectiveTo investigate the expressions of microRNA-155 (miR-155) in different phenotypes of activated macrophages.
MethodsThe THP-1 cells underwent polarized activation into M1, M2 or tumor-associated macrophages (TAMs), and the phenotypes were confirmed by flow cytometry. The miR-155 expression was determined by qRt-PCR in M1 macrophages, M2 macrophages and TAMs.
ResultsThe miR-155 expression significantly decreased in the M2 macrophages (1.83±0.337, P=0.000), TAMs (1.60±0.233, P=0.000) compared with the M1 (6.580±0.637). The phenotype of TAMs was similar to M2. There was no statistically significant difference between TAMs and M2 macrophages in the expression of miR-155 (P=0.546).
ConclusionDifferent expressions of miR-155 in macrophages M1-type and M2-type may be associated with the differentiation or their cellular functions. The phenotypic characteristics TAMs may transform to macrophages to M2-type. And they may have the same functions.
ObjectiveTo investigate the effect of miR-190a-5p on the polarization of bone-marrow-derived macrophage (BMDM) induced by lipopolysaccharides to M1- and M2-types.MethodsBMDM (M1-type) induced by bacterial lipopolysaccharide was a M1 group. The macrophage M1-type interfered with negative control miRNA mimics was a NC group. miR-190a-5p mimics interfered with the M1-type of macrophages in the miR-190a-5p group. Morphological changes of macrophages were observed under a microscope, and the proportion of M2-type macrophages (CD206+, F4/80) was detected by flow cytometry. The mRNA expression levels of argininase-1 (Arg1), inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), target gene C/EBPα and PU.1 were detected by fluorescence quantitative PCR to verify whether C/EBPα and PU.1 were potential target genes of miR-190a-5p. The expression of pathway proteins C/EBPα and PU.1 were detected by Western blotting.ResultsAfter miR-190a-5p mimics interfered with macrophage M1-type, the antenna of macrophages elongated and showed long cord M2-type cell morphological characteristics. miR-190a-5p mimics interfered with M1-type macrophages for 24 h, and the percentage of M2-type macrophages increased significantly (P<0.05). Effects of miR-190a-5p simulator on mRNA expression levels of M1-type macrophages included: the expression of iNOS and TNF-α was significantly decreased (P<0.05), the expression of Arg1 marked by M2 macrophages was significantly increased (P<0.05), and the mRNA expression levels of target genes C/EBPα and PU.1 were significantly decreased (P<0.05). Western blotting results showed that the overexpression of miR-190a-5p significantly inhibited the protein expressions of C/EBPα and PU.1, while the miR-190a-5p inhibitor increased the expressions of both proteins.ConclusionmiR-190a-5p can promote the polarization of BMDM from M1-type to M2-type.
Objective To explore the role of macrophage-stimulating protein ( MSP) and receptor tyrosine kinase RON in the airway inflammation of chronic obstructive pulmonary disease( COPD) , and investigate its possible mechanism. Methods The rat COPDmodel was established by exposing the rats to cigarette smoke daily for three months. Rat alveolar macrophages ( AMs) were isolated in vivo and cultured,and then challenged with different concentrations of MSP for 24 hours. The concentrations of MSP in broncho-alveolar lavage fluid ( BALF) and serum, and the levels of IL-1β, TNF-α, IL-8, and IL-10 in the supernatants were measured by ELISA. The expression of RONmRNA in lung tissue was assessed by reverse transcription-polymerase chain reaction. The levels of RON protein in the lung tissue and AMs cultured in vitro were observed by immunohistochemistry. The activity of superoxide dismutase ( SOD) and malondialdehyde ( MDA) content in the culture solution were measured with chromatometry method. Results Compared with the control group, the concentrations of MSP in serum and BALF of the COPD rats were significantly higher ( P lt;0. 01) . The levels of RONmRNA and RON protein in the COPD rats were also upregulated significantly ( P lt; 0. 01) . MSP evoked the AMs isolated from the normal and COPD rats to generate more content of MDA and caused a reduction in activity of SOD. In addition, MSP stimulated TNF-α, IL-8, IL-1βand IL-10 release fromAMs of the normal and COPD rats dose-dependently. The levels of TNF-α, IL-8, and IL-1βwere higher, while the level of IL-10 and the SOD activity were lower in AMs of the COPD group than those of the control group in the same dose of MSP ( P lt;0. 01) . The more significant increase in the levels of TNF-α, IL-8, IL-1β, and the more notable decrease in the activity of SOD was found in the COPD group compared with the control group. But the degree of increasing MDA and IL-10 in the AMs of the COPD group was lower than that in the control group. Linear correlation analysis showed that the MSP concentration and the RON protein level in the COPD rats were positively associated with the total cellcounts and AM counts in BALF, and were related to the indexes for pulmonary emphysema. Conclusions There is a close correlation between the MSP and receptor tyrosine kinase RON with the airway inflammation of COPD. The mechanism might be that MSP promote the macrophages release inflammatory factors and increase the production of oxygen free radicals.
ObjectiveTo investigate the effect of succinate induced polarization of MH-S murine alveolar macrophage cells on hyperoxia-induced epithelial-mesenchymal transition (EMT) of MLE-12 mouse alveolar epithelial cells. Methods Determine the exposure time: MLE-12 cells was cultured in an incubator with 95%O2 for different time to establish a cell model of acute hyperoxia-induced lung injury. The relative expression of EMT-related proteins (E-cadherin, N-cadherin, vimentin) was determined by Western blotting. Co-culture of MLE-12 and MH-S to explore the influence of MH-S on EMT: MLE-12 was divided into hyperoxia group for 0h, hyperoxia group for 48h and co-cultured with MH-S hyperoxia group for 48h (Co). The relative expression of EMT-related proteins was determined by Western blotting. Determination of succinate concentration and its effect on MH-S polarization and succinate receptor GPR91: MLE-12 was cultured in different concentrations of succinate medium for 24h, and the cell viability was determined by CCK-8. MH-S was divided into control group (C) and succinate group (S). Group C was cultured for 24h, and group S was added with succinate at the above concentration. The relative expression of GPR91 and polarization-related factor mRNA in MH-S was measured by RT-qPCR, and the expression of macrophage polarization-related proteins (CD11b, CD206, CD86) was measured by flow cytometry. Study on the effect of succinate on EMT by cell co-culture: MLE-12 and MH-S were co-cultured in a Transwell chamber and divided into control group (Co), succinate group (SUC) and GPR91 inhibitor group (I). Results Expression of EMT-related proteins in four groups of MLE-12 at different times: Compared with 0h, the expression of vimentin and N-cadherin in 24h and 48h increased, while the expression of E-cadherin in 48 h and 72 h decreased (P<0.05), and there was no significant difference in other groups. The follow-up experiment was conducted under hyperoxia conditions for 48h. Influence of MH-S on EMT: The expression of vimentin and N-cadherin in Co group was higher than that in 48h, and the expression of E-cadherin was lower than that in 48h (P<0.05). After 24 h of intervention with different concentrations of succinate on MLE-12, compared with the 0mmol/L, the cell viability of 2.5mmol/L, 1mmol/L and 500 μmol/L increased (P<0.05), and there was no significant difference in other groups, so the 1mmol/L succinate concentration was selected for subsequent experiment. Compared with group C, the expression of GPR91 mRNA in group S increased, and the expression of iNOS and CD86 mRNA in group S increased (P<0.05), but there was no significant difference in other groups. The analysis of flow cytometry showed that 1mmol/L succinate could increase the number and proportion of CD86+CD206– alveolar macrophages. Compared with Co group, the expression of vimentin and N-cadherin in SUC group increased, while the expression of E-cadherin decreased. Compared with SUC group, the expression of vimentin and N-cadherin in group I decreased, while the expression of E-cadherin increased (P<0.05). Conclusion Succinate can induce mouse alveolar macrophages polarization to M1 through GPR91, enhance EMT of mouse alveolar epithelial cell injury model under hyperoxia, and promote the formation of pulmonary fibrosis.
