• Biomolecules & Therapeutics
• /
• 제27권6호
• /
• pp.522-529
• /
• 2019

M1/M2 polarization of immune cells including microglia has been well characterized. It mediates detrimental or beneficial roles in neuroinflammatory disorders including cerebral ischemia. We have previously found that sphingosine 1-phospate receptor subtype 1 ($S1P_1$) in post-ischemic brain following transient middle cerebral artery occlusion (tMCAO) can trigger microglial activation, leading to brain damage. Although the link between $S1P_1$ and microglial activation as a pathogenesis in cerebral ischemia had been clearly demonstrated, whether the pathogenic role of $S1P_1$ is associated with its regulation of M1/M2 polarization remains unclear. Thus, this study aimed to determine whether $S1P_1$ was associated with regulation of M1/M2 polarization in post-ischemic brain. Suppressing $S1P_1$ activity with its functional antagonist, AUY954 (5 mg/kg, p.o.), attenuated mRNA upregulation of M1 polarization markers in post-ischemic brain at 1 day and 3 days after tMCAO challenge. Similarly, suppressing $S1P_1$ activity with AUY954 administration inhibited M1-polarizatioin-relevant $NF-{\kappa}B$ activation in post-ischemic brain. Particularly, $NF-{\kappa}B$ activation was observed in activated microglia of post-ischemic brain and markedly attenuated by AUY954, indicating that M1 polarization through $S1P_1$ in post-ischemic brain mainly occurred in activated microglia. Suppressing $S1P_1$ activity with AUY954 also increased mRNA expression levels of M2 polarization markers in post-ischemic brain, further indicating that $S1P_1$ could also influence M2 polarization in post-ischemic brain. Finally, suppressing $S1P_1$ activity decreased phosphorylation of M1-relevant ERK1/2, p38, and JNK MAPKs, but increased phosphorylation of M2-relevant Akt, all of which were downstream pathways following $S1P_1$ activation. Overall, these results revealed $S1P_1$-regulated M1/M2 polarization toward brain damage as a pathogenesis of cerebral ischemia.

• 동의생리병리학회지
• /
• 제38권1호
• /
• pp.32-37
• /
• 2024

The aim of this study was to investigate the role of Daesiho-tang (Da Chai Hu-Tang) water extract (DSTE) in regulating chronic stress-induced cancer progression, focusing on its activity in modulating tumor-associated macrophages (TAMs). Different stimuli can polarize TAMs into immune-stimulating M1 macrophages or immunosuppressive M2 macrophages. During cancer progression, M2 phenotype increases and supports tumor growth, angiogenesis and metastasis. Notably, chronic stress-induced catecholamines promote M2 macrophage polarization. In this study, we investigated whether DSTE regulates norepinephrine (NE)-induced M2 macrophage polarization in RAW 264.7 mouse macrophage cells. Even though NE itself did not increase the expression of M2 markers, the conditioned media of NE-treated 4T1 mouse breast cancer cells (NE CM) significantly up-regulated M2 markers in RAW 264.7 cells, suggesting that NE-regulated cancer cell secretome stimulated M2 polarization. However, such increase was abrogated by DSTE. NE CM also induced phosphorylation of signal transducer and activator of transcription 6 (STAT6) in RAW 264.7 cells, which was clearly reversed by pretreatment with DSTE, demonstrating that DSTE inhibited M2 polarization by inactivating STAT6. Finally, M2-polarized RAW264.7 cells by NE CM markedly increased the migration of 4T1 cells. However, such increase was completely reversed by co-treating RAW264.7 cells with NE CM and DSTE, indicating that DSTE attenuated cancer cell migration by blocking M2 polarization. Taken together, our results suggest a probable use of DSTE for cancer patients under chronic stress by regulating M2 macrophage polarization.

• 대한약침학회지
• /
• 제22권4호
• /
• pp.253-259
• /
• 2019

Objectives: It is reported that tumor-associated macrophages (TAMs) contribute to cancer progression by promoting tumor growth and metastasis. The purpose of this study is to investigate the effect of different fractions of Adenophora triphylla var. japonica (AT) on the polarization of macrophages into the M2 phenotype, a major phenotype of TAMs. Methods: We isolated hexane, ethyl acetate, and butanol fractions from crude ethanol extract of AT. The cytotoxicity of AT in RAW264.7 cells was examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RAW264.7 cells were polarized into the M2 phenotype by treatment with interleukin (IL)-4 and IL-13. The expression of M2 macrophage marker genes was detected by reverse transcription polymerase chain reaction (RT-PCR). The phosphorylation level of signal transducer and activator of transcription 6 (STAT6) was investigated by western blot analysis. The migration of Lewis lung carcinoma (LLC) cells was examined by transwell migration assay using conditioned media (CM) collected from RAW264.7 cells as a chemoattractant. Results: Among various fractions of AT, the ethyl acetate fraction of AT (EAT) showed the most significant suppressive effect on the mRNA expression of M2 macrophage markers, including arginase-1, interleukin (IL)-10 and mannose receptor C type 1 (MRC-1), up-regulated by treatment of IL-4 and IL-13. In addition, EAT suppressed the phosphorylation of STAT6, a critical regulator of IL-4 and IL-13-induced M2 macrophage polarization. Finally, the increased migration of Lewis lung carcinoma (LLC) cells by CM from M2-polarized RAW264.7 cells was reduced by CM from RAW264.7 cells co-treated with EAT and M2 polarization inducers. Conclusion: We demonstrated that EAT attenuated cancer cell migration through suppression of macrophage polarization toward the M2 phenotype. Additional preclinical or clinical researches are needed to evaluate its regulatory effects on macrophage polarization and anti-cancer activities.

• Archives of Plastic Surgery
• /
• 제50권4호
• /
• pp.432-442
• /
• 2023

Background Macrophages play a major role in wound healing and prevent infection from the outside. Polarization conversion of macrophages regulates aspects of inflammation, and two macrophages, M1 (classically activated) and M2 (alternatively activated), exist at both ends of broad-spectrum macrophage polarization. Thus, we aimed to investigate whether macrophage polarization can be artificially regulated. To this end, MgSO4 and small-interfering RNA (siRNA) targeting magnesium transport 1 (MAGT1) were used to investigate the effects of intracellular magnesium (Mg2+) concentrations on the differentiation of macrophages in vitro. Methods THP-1 derived macrophages maintained in a culture medium containing 5 mM MgSO4 and siRNA to inhibit the expression of MAGT1. As comparative groups, THP-1 derived macrophages polarized into M1 and M2 macrophages by treatment with M1, M2 inducer cytokine. The polarization status of each group of cells was confirmed by cell surface antigen expression and cytokine secretion. Results We found that MgSO4 treatment increased CD163 and CD206, similar to the effect noted in the M2 group. The expression of CD80 and HLA-DR was increased in the group treated with MAGT1 siRNA, similar to the effect noted in the M1 group. Functional assays demonstrated that the group treated with MgSO4 secreted higher levels of IL-10, whereas the MAGT1 siRNA-treated group secreted higher levels of IL-6 cytokines. Additionally, the conditional medium of the Mg2+ treated group showed enhanced migration of keratinocytes and fibroblasts. Conclusion Mg2+ can help to end the delay in wound healing caused by persistent inflammation in the early stages.

• The Korean Journal of Physiology and Pharmacology
• /
• 제27권5호
• /
• pp.437-448
• /
• 2023

Diabetic ulcer is usually seen in people with uncontrolled blood sugar. Reportedly, many factors such as impaired glucose metabolism, and macrovascular and microvascular diseases caused angiogenesis disorders and delayed the healing of diabetic ulcers, thus affecting the body's metabolism, nutrition, and immune function. This study aimed to explore the effect of paeonol on skin wound healing in diabetic rats and the related mechanism. A rat model of diabetic ulcer was established. High glucose-treated mouse skin fibroblasts were co-cultured with M1 or M2-polarized macrophages treated with or without paeonol. H&E and Masson staining were used to reveal inflammatory cell infiltration and collagen deposition, respectively. Immunohistochemistry visualized the expression of Ki67, CD31, and vascular endothelial growth factor (VEGF). Western blot was used to detect interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-4, IL-10, CD31, VEGFA, and collagen I/III. The expression of iNOS and arginase 1 was revealed by immunofluorescence staining. Paeonol treatment augmented collagen deposition and the expression of Ki67, CD31, VEGF, and macrophage M2 polarization markers (IL-4 and IL-10) and reduced wound area, inflammatory cell infiltration, and macrophage M1 polarization markers (IL-1β and TNF-α) in the ulcerated area. In vitro, paeonol treatment promoted M2-polarization and repressed M1-polarization in macrophages, thereby improving the repair of cell damage induced by high glucose. Paeonol accelerates the healing of diabetic ulcers by promoting M2 macrophage polarization and inhibiting M1 macrophage polarization.

• 한국자기공명학회논문지
• /
• 제21권4호
• /
• pp.114-118
• /
• 2017

Here, I report solid state Dynamic Nuclear Polarization (DNP) of $^1H$ nuclear spins at 0.3 T and 4.2 K. The DNP polarizer was developed based on a commercial X-band Electron Spin Resonance (ESR) modified for DNP, in combination with a NMR console and a liquid-Helium cryostat. By detuning magnetic field, DNP spectrum was measured to find the optimal condition. At +3 mT detuned from on-resonance field, $^1H$ NMR signal of 60:40 glycerol/water frozen solution doped with 20 mM perdeuterated-Tempone was amplified 43 times. The $^1H$ spin polarization obtained at 4.2 K is over 3100 times higher than that at 300 K. The width of the DNP spectrum, which is five times broader than ESR spectrum, is inconsistent with solid effect or thermal mixing, and presumably suggests a different DNP mechanism.

• 생명과학회지
• /
• 제30권2호
• /
• pp.113-121
• /
• 2020

대식세포는 특성에 따라 크게 classically activated macrophages (M1-phenotype macrophages)와 alternatively activated macrophages (M2-phenotype macrophages) 두 가지의 형태로 나눌 수 있다. M1 대식세포의 경우 직·간접적으로 병원체, 감염된 조직 및 암세포 등을 제거하는 능력을 가진 반면, M2 대식세포의 경우 항염증 반응을 동반한 손상된 세포 조직의 복구 및 세포외기질의 생성에 관여하고 있다. 본 연구에서는 상황버섯 열수추출물을 합성 흡착제인 Diaion HP-20에 통과시켜 소수성 물질을 제거한 시료(PLEP)을 이용하여 인간 유래 THP-1 단핵구 세포주의 염증성 혹은 항염증성 분극화 특성을 알아보았다. 먼저 PLEP 자체의 단핵구 세포에 대한 세포독성을 확인한 결과, 고농도의 300 ㎍/ml에서 세포독성이 확인되지 않았다. 한편 세포의 형태학적 변화를 확인한 결과, PLEP의 농도가 증가함에 따라 M1- phenotype 대식세포와 유사한 flatted and branched 형태가 증가하였다. 대식세포로 분화시킨 THP-1 세포주에 PLEP를 처리한 후, M1 대식세포 분극화 관련 유전자인 TNFα, IL-1β, IL-6, IL-8, CXCL10, CCR7과 M2-분극화 관련 유전자인 MRC-1, DC-SIGN, CCL17, CCL22의 유전자 발현량을 조사하여 분극화 양상을 알아보았다. 그 결과, M1-분극화 관련 유전자들은 PLEP 농도 의존적으로 증가하였지만, M2-분극화 관련 유전자들은 반대로 감소하였다. 또한 ELISA assay를 통하여 M1 분극화 관련 cytokine인 TNFα, IL-1β, IL-6의 발현량이 유전자의 발현량과 동일하게 증가하였다. 이러한 cytokine들의 분비를 촉진시키는 MAPK signaling 또한 PLEP의 농도가 증가함에 따라 촉진되었고 염증성 cytokine과 관련된 전사인자 NF-κB의 활성화도 증가하였다. 따라서 PLEP는 인간 유래 THP-1 세포주에서의 M1 대식세포 분극화를 통해 염증 반응을 유발하는 것으로 확인되어 염증을 촉진하는 천연물질로 이용할 수 있을 것으로 전망된다.

• 수산해양교육연구
• /
• 제18권1호
• /
• pp.58-64
• /
• 2006

In order to examine the effect of humidity on hydrogen embrittlement of STS 444 weld zone for boiler with dry and wet welding conditions, this paper was carried out the accelerated hydrogen osmosis test and the electrochemical Tafel polarization test. In 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution, this test is added to load of $1400kg/cm^2$ together with hydrogen osmosis by current of $50 {mA/cm^2}$ for 60 min.. The electrochemical Tafel polarization test was carried out in 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution. Therefore, the effect of humidity on hydrogen embrittlement of STS 444 was considered. The main results are as following: On the basis of hydrogen embrittlement mechanism, that is, integrated electrochemical polarization characteristics with the established mechanism of hydrogen embrittlement, the reduction rate of corrosion current density of weld zone in the wet weld condition is larger than in the dry condition. We can nondestructively predict the degree of hydrogen embrittlement of STS 444 weld zone for boiler through the reduction rate of electrochemical corrosion current density.

• Journal of Ginseng Research
• /
• 제42권1호
• /
• pp.68-74
• /
• 2018

Background: Ginsenosides have been reported to have many health benefits, including anti-inflammatory effects, and the resolution of inflammation is now considered to be an active process driven by M2-type macrophages. In order to determine whether ginsenosides modulate macrophage phenotypes to reduce inflammation, 11 ginsenosides were studied with respect to macrophage polarization and the resolution of inflammation. Methods: Mouse peritoneal macrophages were polarized into M1 or M2 phenotypes. Reverse transcription-polymerase chain reaction, Western blotting, and measurement of nitric oxide (NO) and prostaglandin $E_2$ levels were performed in vitro and in a zymosan-induced peritonitis C57BL/6 mouse model. Results: Ginsenoside $Rg_3$ was identified as a proresolving ginseng compound based on the induction of M2 macrophage polarization. Ginsenoside $Rg_3$ not only induced the expression of arginase-1 (a representative M2 marker gene), but also suppressed M1 marker genes, such as inducible NO synthase, and NO levels. The proresolving activity of ginsenoside $Rg_3$ was also observed in vivo in a zymosan-induced peritonitis model. Ginsenoside $Rg_3$ accelerated the resolution process when administered at peak inflammatory response into the peritoneal cavity. Conclusion: These results suggest that ginsenoside $Rg_3$ induces the M2 polarization of macrophages and accelerates the resolution of inflammation. This finding opens a new avenue in ginseng pharmacology.

• 대한방사성의약품학회지
• /
• 제7권1호
• /
• pp.41-49
• /
• 2021

Diversity and flexibility are two typical hallmarks of macrophages. Two types of macrophages, M1(classically activated macrophages) and M2(alternatively activated macrophages) exist at both ends of the commonly known macrophage polarization. M1 macrophages have inflammatory properties and are primarily responsible for defending against invading bacteria in our body. On the other hand, M2 macrophages are involved in anti-inflammatory responses and tissue remodeling. Polarized migration of macrophages is of increasing interest in regulating the initiation, generation, and resting phases of inflammatory diseases. In this review, it intend to discuss the properties and functions of tumor-associated macrophages based on polarized macrophages that affect inflammatory diseases. In addition, the purpose of this study is to investigate a molecular imaging approach that targets macrophages that affect tumor growth by controlling the polarization of macrophages that affect tumor diagnosis and treatment.