1.Yishen Huashi Granules Protect Kidneys of db/db Mice via p38 MAPK Signaling Pathway
Kaidong ZHOU ; Sitong WANG ; Ge JIN ; Yanmo CAI ; Xin ZHOU ; Yunhua LIU ; Xinxue ZHANG ; Min ZHANG ; Zongjiang ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(3):58-68
ObjectiveTo explore the mechanism of Yishen Huashi granules in alleviating renal tubular epithelial cell injury and relieving diabetic kidney disease by regulating the mitogen-activated protein kinase (MAPK) signaling pathway. MethodsThe db/db mice of 12 weeks old were randomly assigned into model , dapagliflozin (1.6 mg·kg-1), and Yishen Huashi granules (4.7 g·kg-1), and db/m mice were used as the control group. The general conditions of mice were observed, and fasting blood glucose and 24-h urinary protein and albumin-to-creatinine ratio (ACR) were measured at weeks 0 and 12 of administration. After 12 weeks of treatment, the levels of serum creatinine (SCr), blood urea (UREA), triglycerides (TG), total cholesterol (TC), and low density lipoprotein (LDL) were measured. The pathological changes in the renal tissue were observed by hematoxylin-eosin (HE) staining, Periodic acid-Schiff (PAS) staining, Mallory staining, and transmission electron microscopy. Real-time PCR was employed to determine the mRNA levels of monocyte chemotactic protein-1 (MCP-1) and CC chemokine receptor-2 (CCR2) in the renal tissue of mice. The immunohistochemical assay was employed to examine the expression of p38, phospho-p38 (p-p38), MCP-1, and CCR2 in the renal tissue of mice. Western blotting was employed to measure the protein levels of p-p38, p38, MCP-1, and CCR2 in the renal tissue of mice.HK-2 cells cultured in vitro were grouped as follows: negative control, high glucose(30 mmol·L-1), Yishen Huashi granule-containing serum, and SB203580. After 48 h of cell culture in each group, RNA were extracted and the levels of MCP-1, and CCR2 mRNA were determined by Real-time PCR,proteins were extracted and the levels of p38, p-p38, MCP-1, and CCR2 were determined by Western blot. ResultsThe in vivo experiments showed that before treatment, other groups had higher body weight, blood glucose level, 24 h urinary protein, and ACR than the control group (P<0.05,P<0.01). After 12 weeks of treatment, compared with the model group, the Yishen Huashi granules group showed improved general conditions, a decreasing trend in body weight, lowered levels of blood glucose, 24-h urinary protein, and ACR (P<0.01), reduced SCr and UREA (P<0.01), and declined levels of TC, TG, and LDL (P<0.05,P<0.01). Compared with the model group, the Yishen Huashi granules group showed alleviated damage and interstitial fibrosis in the renal tissue as well as reductions in glomerular foot process fusion and basement membrane thickening. Moreover, the Yishen Huashi granules group showed down-regulated mRNA levels of MCP-1 and CCR2 (P<0.01), reduced positive expression of p-p38, MCP-1, and CCR2 (P<0.01), and down-regulated protein levels of p-p38/p38, MCP-1, and CCR2 (P<0.05) in the renal tissue. The cell experiment showed that compared with the high glucose group, the Yishen Huashi granule-containing serum group showcased down-regulated mRNA levels of MCP-1 and CCR2 (P<0.01) and down-regulated protein levels of p-p38/p38, MCP-1, and CCR2(P<0.05,P<0.01). ConclusionYishen Huashi granules can regulate glucose-lipid metabolism, reduce 24 h urinary protein and ACR, improve the renal function, alleviate the renal tubule injury caused by high glucose, and protect renal tubule epithelial cells in db/db mice by reducing MCP-1/CCR2 activation via the p38 MAPK signaling pathway.
2.Current Status and Prospects of Research on the Potential Neurobiological Mechanisms of Acupuncture in the Treatment of Tobacco Dependence
Shumin CHEN ; Jin CHANG ; Chaoren TAN ; Hao ZHU ; Jinsheng YANG ; Zhao LIU ; Yingying WANG
Journal of Traditional Chinese Medicine 2025;66(4):421-426
This paper comprehensively discusses on the potential neurobiological mechanisms of acupuncture in the treatment of tobacco dependence, focusing on three important aspects, including acupuncture's regulation of tobacco dependence behavior, effects of acupuncture on withdrawal syndrome, and the role of acupuncture in preventing relapse. It is found that acupuncture can inhibit drug-seeking behavior by regulating the reward pathway and related neurons, such as dopamine, thus modulating tobacco dependence behavior. It also alleviates withdrawal symptoms by improving the oral environment of smokers and reducing negative emotions after quitting. Furthermore, acupuncture can prevent relapse by decreasing brain network activity related to smoking cravings and improving cognitive brain functions like addiction memory. Currently, research on the specific neurobiological mechanism of acupuncture in treating tobacco dependence and the involved neural circuits is limited. Future research directions are proposed, including the evaluation of clinical effects, exploration of specific therapeutic mechanisms, investigation of brain pathology, and strengthening the exploration of brain functions. Additionally, combining modern technologies to clarify the neural circuits involved in acupuncture intervention will provide a basis for acupuncture treatment of tobacco addiction.
3.Mid-long term follow-up reports on head and neck rhabdomyosarcoma in children
Chao DUAN ; Sidou HE ; Shengcai WANG ; Mei JIN ; Wen ZHAO ; Xisi WANG ; Zhikai LIU ; Tong YU ; Lejian HE ; Xiaoman WANG ; Chunying CUI ; Xin NI ; Yan SU
Chinese Journal of Pediatrics 2025;63(1):62-69
Objective:To analyze the clinical characteristics of children with head and neck rhabdomyosarcoma (RMS) and to summarize the mid-long term efficacy of Beijing Children′s Hospital Rhabdomyosarcoma 2006 (BCH-RMS-2006) regimen and China Children′s Cancer Group Rhabdomyosarcoma 2016 (CCCG-RMS-2016) regimen.Methods:A retrospective cohort study. Clinical data of 137 children with newly diagnosed head and neck RMS at Beijing Children′s Hospital, Capital Medical University from March 2013 to December 2021 were collected. Clinical characteristic of patients at disease onset and the therapeutic effects of patients treated with the BCH-RMS-2006 and CCCG-RMS-2016 regimens were compared. The treatments and outcomes of patients with recurrence were also summarized. Survival analysis was performed by Kaplan-Meier method, and Log-Rank test was used for comparison of survival rates between groups.Results:Among 137 patients, there were 80 males (58.4%) and 57 females (41.6%), the age of disease onset was 59 (34, 97) months. The primary site in the orbital, non-orbital non-parameningeal, and parameningeal area were 10 (7.3%), 47 (34.3%), and 80 (58.4%), respectively. Of all patients, 32 cases (23.4%) were treated with the BCH-RMS-2006 regimen and 105 (76.6%) cases were treated with the CCCG-RMS-2016 regimen. The follow-up time for the whole patients was 46 (20, 72) months, and the 5-year progression free survival (PFS) and overall survival (OS) rates for the whole children were (60.4±4.4)% and (69.3±4.0)%, respectively. The 5-year OS rate was higher in the CCCG-RMS-2016 group than in BCH-RMS-2006 group ((73.0±4.5)% vs. (56.6±4.4)%, χ2=4.57, P=0.029). For the parameningeal group, the 5-year OS rate was higher in the CCCG-RMS-2016 group (61 cases) than in BCH-RMS-2006 group (19 cases) ((57.3±7.6)% vs. (32.7±11.8)%, χ2=4.64, P=0.031). For the group with meningeal invasion risk factors, the 5-year OS rate was higher in the CCCG-RMS-2016 group (54 cases) than in BCH-RMS-2006 group (15 cases) ((57.7±7.7)% vs. (30.0±12.3)%, χ2=4.76, P=0.029). Among the 10 cases of orbital RMS, there was no recurrence. In the non-orbital non-parameningeal RMS group (47 cases), there were 13 (27.6%) recurrences, after re-treatment, 7 cases survived. In the parameningeal RMS group (80 cases), there were 40 (50.0%) recurrences, with only 7 cases surviving after re-treatment. Conclusions:The overall prognosis for patients with orbital and non-orbital non-parameningeal RMS is good. However, children with parameningeal RMS have a high recurrence rate, and the effectiveness of re-treatment after recurrence is poor. Compared with the BCH-RMS-2006 regimen, the CCCG-RMS-2016 regimen can improve the treatment efficacy of RMS in the meningeal region.
4.Effect of Shenkang Injection on Podocyte Apoptosis and GRP78/CHOP Signaling Pathway in db/db Mice with Diabetic Kidney Disease Based on Endoplasmic Reticulum Stress
Yanmo CAI ; Sitong WANG ; Xin ZHOU ; Ge JIN ; Kaidong ZHOU ; Yunhua LIU ; Fengfeng ZHANG ; Xinxue ZHANG ; Zongjiang ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(12):81-90
ObjectiveTo investigate the mechanism of Shenkang injection in delaying diabetic kidney disease by regulating endoplasmic reticulum stress and attenuating podocyte apoptosis through the Glucose regulated protein 78 ( GRP78 ) / transcription factor C / EBP homologous protein ( CHOP ) signaling pathway (GRP78/CHOP) signaling pathway. MethodsFor the animal experiment, 10 12-week-old db/m mice were selected as a normal group, and 30 12-week-old db/db mice were randomly divided into a model group, a Shenkang injection group (15.6 mL·kg-1), and a dapagliflozin group (1.6 mg·kg-1). To observe the general condition of mice, fasting blood glucose, urinary albumin/urine creatinine (ACR), and 24 h urine protein quantification were detected in each group before drug administration. After 12 weeks of drug treatment, mice were tested for fasting blood glucose, total cholesterol (TC), triglyceride (TG), low-density cholesterol (LDL), ACR, 24 h urine protein quantification, blood creatinine (SCr), and blood urea (UREA). Hematoxylin-eosin (HE) staining, periodic acid-Schiff (PAS) staining, and transmission electron microscopy were used to observe the pathologic morphology in renal tissue. Immunohistochemistry was used to detect the expressions of nephroprotective marker protein (Nephrin), glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X protein (Bax) in renal tissue. Western blot was used to detect the expressions of GRP78, CHOP, Bcl-2, Bax, and Nephrin proteins, and Real-time polymerase chain reaction (Real-time PCR) was employed to detect the expressions of Nephrin, GRP78, CHOP, Bcl-2, and Bax mRNAs in renal tissue. ResultsBefore drug administration, compared with those in the normal group, the body mass of db/db mice was significantly increased, and blood glucose, 24 h urine protein quantification, and ACR were significantly elevated in the Shenkang injection group and Dapagliflozin group (P<0.01). After 12 weeks of administration, compared with those in the model group, the general state of mice in the Shenkang injection group was significantly improved, and the body mass was decreased. The blood glucose was significantly reduced (P<0.01), and blood lipids TC, TG, and LDL were significantly decreased (P<0.05, P<0.01). The 24 h urine protein quantification and ACR were significantly decreased (P<0.05), and SCr and UREA were significantly reduced (P<0.01). Compared with those of the model group, the pathologic results of the Shenkang injection group showed that proliferation of mesangial cells, reduction of inflammatory cell infiltration, and alleviation of renal tubular vacuolization and podocyte damage were observed in renal tissue of mice. Electron microscopy showed that fusion of the pedicle protruding and thickening of the basement membrane were reduced. Immunohistochemistry results showed that the expressions of GRP78, CHOP, and Bax proteins were significantly reduced (P<0.01), and the expressions of Nephrin and Bcl-2 proteins were significantly increased (P<0.01) in renal tissue of the Shenkang injection group. Western blot results showed that the expressions of Nephrin and Bcl-2 in the Shenkang injection group were significantly increased (P<0.05, P<0.01), and the expressions of GRP78, CHOP, and Bax proteins were significantly decreased (P<0.05, P<0.01). Real-time PCR results showed that the expressions of GRP78, CHOP, and Bax mRNAs were down regulated in the Shenkang injection group (P<0.01), and the expressions of Nephrin and Bcl-2 mRNAs were up regulated (P<0.01). ConclusionShenkang injection inhibits endoplasmic reticulum stress response and podocyte apoptosis by regulating the GRP78/CHOP signaling pathway, which in turn ensures the integrity of glomerular filtration barrier, reduces the occurrence of proteinuria, improves renal function, and thus delays the progression of diabetic kidney disease.
5.Effect of Shenkang Injection on Podocyte Apoptosis and GRP78/CHOP Signaling Pathway in db/db Mice with Diabetic Kidney Disease Based on Endoplasmic Reticulum Stress
Yanmo CAI ; Sitong WANG ; Xin ZHOU ; Ge JIN ; Kaidong ZHOU ; Yunhua LIU ; Fengfeng ZHANG ; Xinxue ZHANG ; Zongjiang ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(12):81-90
ObjectiveTo investigate the mechanism of Shenkang injection in delaying diabetic kidney disease by regulating endoplasmic reticulum stress and attenuating podocyte apoptosis through the Glucose regulated protein 78 ( GRP78 ) / transcription factor C / EBP homologous protein ( CHOP ) signaling pathway (GRP78/CHOP) signaling pathway. MethodsFor the animal experiment, 10 12-week-old db/m mice were selected as a normal group, and 30 12-week-old db/db mice were randomly divided into a model group, a Shenkang injection group (15.6 mL·kg-1), and a dapagliflozin group (1.6 mg·kg-1). To observe the general condition of mice, fasting blood glucose, urinary albumin/urine creatinine (ACR), and 24 h urine protein quantification were detected in each group before drug administration. After 12 weeks of drug treatment, mice were tested for fasting blood glucose, total cholesterol (TC), triglyceride (TG), low-density cholesterol (LDL), ACR, 24 h urine protein quantification, blood creatinine (SCr), and blood urea (UREA). Hematoxylin-eosin (HE) staining, periodic acid-Schiff (PAS) staining, and transmission electron microscopy were used to observe the pathologic morphology in renal tissue. Immunohistochemistry was used to detect the expressions of nephroprotective marker protein (Nephrin), glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X protein (Bax) in renal tissue. Western blot was used to detect the expressions of GRP78, CHOP, Bcl-2, Bax, and Nephrin proteins, and Real-time polymerase chain reaction (Real-time PCR) was employed to detect the expressions of Nephrin, GRP78, CHOP, Bcl-2, and Bax mRNAs in renal tissue. ResultsBefore drug administration, compared with those in the normal group, the body mass of db/db mice was significantly increased, and blood glucose, 24 h urine protein quantification, and ACR were significantly elevated in the Shenkang injection group and Dapagliflozin group (P<0.01). After 12 weeks of administration, compared with those in the model group, the general state of mice in the Shenkang injection group was significantly improved, and the body mass was decreased. The blood glucose was significantly reduced (P<0.01), and blood lipids TC, TG, and LDL were significantly decreased (P<0.05, P<0.01). The 24 h urine protein quantification and ACR were significantly decreased (P<0.05), and SCr and UREA were significantly reduced (P<0.01). Compared with those of the model group, the pathologic results of the Shenkang injection group showed that proliferation of mesangial cells, reduction of inflammatory cell infiltration, and alleviation of renal tubular vacuolization and podocyte damage were observed in renal tissue of mice. Electron microscopy showed that fusion of the pedicle protruding and thickening of the basement membrane were reduced. Immunohistochemistry results showed that the expressions of GRP78, CHOP, and Bax proteins were significantly reduced (P<0.01), and the expressions of Nephrin and Bcl-2 proteins were significantly increased (P<0.01) in renal tissue of the Shenkang injection group. Western blot results showed that the expressions of Nephrin and Bcl-2 in the Shenkang injection group were significantly increased (P<0.05, P<0.01), and the expressions of GRP78, CHOP, and Bax proteins were significantly decreased (P<0.05, P<0.01). Real-time PCR results showed that the expressions of GRP78, CHOP, and Bax mRNAs were down regulated in the Shenkang injection group (P<0.01), and the expressions of Nephrin and Bcl-2 mRNAs were up regulated (P<0.01). ConclusionShenkang injection inhibits endoplasmic reticulum stress response and podocyte apoptosis by regulating the GRP78/CHOP signaling pathway, which in turn ensures the integrity of glomerular filtration barrier, reduces the occurrence of proteinuria, improves renal function, and thus delays the progression of diabetic kidney disease.
6.Retinoic acid ameliorates rheumatoid arthritis by attenuating inflammation and modulating macrophage polarization through MKP-1/MAPK signaling pathway
Mengyuan XIN ; Hangyu JIN ; Xiangyu GUO ; Liang ZHAO ; Xiangdan LI ; Dongyuan XU ; Long ZHENG ; Lan LIU
The Korean Journal of Physiology and Pharmacology 2025;29(1):45-56
Macrophages are innate immune cells connected with the development of inflammation. Retinoic acid has previously been proved to have anti-inflammatory and anti-arthritic properties. However, the exact mechanism through which retinoic acid modulates arthritis remains unclear. This study aimed to investigate whether retinoic acid ameliorates rheumatoid arthritis by modulating macrophage polarization. This study used retinoic acid to treat mice with adjuvant arthritis and evaluated anti-inflammatory effects by arthritis score, thermal nociceptive sensitization test, histopathologic examination and immunofluorescence assays. In addition, its specific anti-arthritic mechanism was investigated by flow cytometry, cell transfection and inflammatory signaling pathway assays in RAW264.7 macrophages in vitro. Retinoic acid significantly relieved joint pain and attenuated inflammatory cell infiltration in mice. Furthermore, this treatment modulated peritoneal macrophage polarization, increased levels of arginase 1, as well as decreased inducible nitric oxide synthase expression. In vitro, we verified that retinoic acid promotes macrophage transition from the M1 to M2 type by upregulating mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) expression and inhibiting P38, JNK and ERK phosphorylation in lipopolysaccharide-stimulated RAW264.7 cells. Notably, the therapeutic effects of retinoic acid were inhibited by MKP-1 knockdown. Retinoic acid exerts a significant therapeutic effect on adjuvant arthritis in mice by regulating macrophage polarization through the MKP-1/MAPK pathway, and play an important role in the treatment of rheumatic diseases.
7.Retinoic acid ameliorates rheumatoid arthritis by attenuating inflammation and modulating macrophage polarization through MKP-1/MAPK signaling pathway
Mengyuan XIN ; Hangyu JIN ; Xiangyu GUO ; Liang ZHAO ; Xiangdan LI ; Dongyuan XU ; Long ZHENG ; Lan LIU
The Korean Journal of Physiology and Pharmacology 2025;29(1):45-56
Macrophages are innate immune cells connected with the development of inflammation. Retinoic acid has previously been proved to have anti-inflammatory and anti-arthritic properties. However, the exact mechanism through which retinoic acid modulates arthritis remains unclear. This study aimed to investigate whether retinoic acid ameliorates rheumatoid arthritis by modulating macrophage polarization. This study used retinoic acid to treat mice with adjuvant arthritis and evaluated anti-inflammatory effects by arthritis score, thermal nociceptive sensitization test, histopathologic examination and immunofluorescence assays. In addition, its specific anti-arthritic mechanism was investigated by flow cytometry, cell transfection and inflammatory signaling pathway assays in RAW264.7 macrophages in vitro. Retinoic acid significantly relieved joint pain and attenuated inflammatory cell infiltration in mice. Furthermore, this treatment modulated peritoneal macrophage polarization, increased levels of arginase 1, as well as decreased inducible nitric oxide synthase expression. In vitro, we verified that retinoic acid promotes macrophage transition from the M1 to M2 type by upregulating mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) expression and inhibiting P38, JNK and ERK phosphorylation in lipopolysaccharide-stimulated RAW264.7 cells. Notably, the therapeutic effects of retinoic acid were inhibited by MKP-1 knockdown. Retinoic acid exerts a significant therapeutic effect on adjuvant arthritis in mice by regulating macrophage polarization through the MKP-1/MAPK pathway, and play an important role in the treatment of rheumatic diseases.
8.Retinoic acid ameliorates rheumatoid arthritis by attenuating inflammation and modulating macrophage polarization through MKP-1/MAPK signaling pathway
Mengyuan XIN ; Hangyu JIN ; Xiangyu GUO ; Liang ZHAO ; Xiangdan LI ; Dongyuan XU ; Long ZHENG ; Lan LIU
The Korean Journal of Physiology and Pharmacology 2025;29(1):45-56
Macrophages are innate immune cells connected with the development of inflammation. Retinoic acid has previously been proved to have anti-inflammatory and anti-arthritic properties. However, the exact mechanism through which retinoic acid modulates arthritis remains unclear. This study aimed to investigate whether retinoic acid ameliorates rheumatoid arthritis by modulating macrophage polarization. This study used retinoic acid to treat mice with adjuvant arthritis and evaluated anti-inflammatory effects by arthritis score, thermal nociceptive sensitization test, histopathologic examination and immunofluorescence assays. In addition, its specific anti-arthritic mechanism was investigated by flow cytometry, cell transfection and inflammatory signaling pathway assays in RAW264.7 macrophages in vitro. Retinoic acid significantly relieved joint pain and attenuated inflammatory cell infiltration in mice. Furthermore, this treatment modulated peritoneal macrophage polarization, increased levels of arginase 1, as well as decreased inducible nitric oxide synthase expression. In vitro, we verified that retinoic acid promotes macrophage transition from the M1 to M2 type by upregulating mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) expression and inhibiting P38, JNK and ERK phosphorylation in lipopolysaccharide-stimulated RAW264.7 cells. Notably, the therapeutic effects of retinoic acid were inhibited by MKP-1 knockdown. Retinoic acid exerts a significant therapeutic effect on adjuvant arthritis in mice by regulating macrophage polarization through the MKP-1/MAPK pathway, and play an important role in the treatment of rheumatic diseases.
9.Retinoic acid ameliorates rheumatoid arthritis by attenuating inflammation and modulating macrophage polarization through MKP-1/MAPK signaling pathway
Mengyuan XIN ; Hangyu JIN ; Xiangyu GUO ; Liang ZHAO ; Xiangdan LI ; Dongyuan XU ; Long ZHENG ; Lan LIU
The Korean Journal of Physiology and Pharmacology 2025;29(1):45-56
Macrophages are innate immune cells connected with the development of inflammation. Retinoic acid has previously been proved to have anti-inflammatory and anti-arthritic properties. However, the exact mechanism through which retinoic acid modulates arthritis remains unclear. This study aimed to investigate whether retinoic acid ameliorates rheumatoid arthritis by modulating macrophage polarization. This study used retinoic acid to treat mice with adjuvant arthritis and evaluated anti-inflammatory effects by arthritis score, thermal nociceptive sensitization test, histopathologic examination and immunofluorescence assays. In addition, its specific anti-arthritic mechanism was investigated by flow cytometry, cell transfection and inflammatory signaling pathway assays in RAW264.7 macrophages in vitro. Retinoic acid significantly relieved joint pain and attenuated inflammatory cell infiltration in mice. Furthermore, this treatment modulated peritoneal macrophage polarization, increased levels of arginase 1, as well as decreased inducible nitric oxide synthase expression. In vitro, we verified that retinoic acid promotes macrophage transition from the M1 to M2 type by upregulating mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) expression and inhibiting P38, JNK and ERK phosphorylation in lipopolysaccharide-stimulated RAW264.7 cells. Notably, the therapeutic effects of retinoic acid were inhibited by MKP-1 knockdown. Retinoic acid exerts a significant therapeutic effect on adjuvant arthritis in mice by regulating macrophage polarization through the MKP-1/MAPK pathway, and play an important role in the treatment of rheumatic diseases.
10.Retinoic acid ameliorates rheumatoid arthritis by attenuating inflammation and modulating macrophage polarization through MKP-1/MAPK signaling pathway
Mengyuan XIN ; Hangyu JIN ; Xiangyu GUO ; Liang ZHAO ; Xiangdan LI ; Dongyuan XU ; Long ZHENG ; Lan LIU
The Korean Journal of Physiology and Pharmacology 2025;29(1):45-56
Macrophages are innate immune cells connected with the development of inflammation. Retinoic acid has previously been proved to have anti-inflammatory and anti-arthritic properties. However, the exact mechanism through which retinoic acid modulates arthritis remains unclear. This study aimed to investigate whether retinoic acid ameliorates rheumatoid arthritis by modulating macrophage polarization. This study used retinoic acid to treat mice with adjuvant arthritis and evaluated anti-inflammatory effects by arthritis score, thermal nociceptive sensitization test, histopathologic examination and immunofluorescence assays. In addition, its specific anti-arthritic mechanism was investigated by flow cytometry, cell transfection and inflammatory signaling pathway assays in RAW264.7 macrophages in vitro. Retinoic acid significantly relieved joint pain and attenuated inflammatory cell infiltration in mice. Furthermore, this treatment modulated peritoneal macrophage polarization, increased levels of arginase 1, as well as decreased inducible nitric oxide synthase expression. In vitro, we verified that retinoic acid promotes macrophage transition from the M1 to M2 type by upregulating mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) expression and inhibiting P38, JNK and ERK phosphorylation in lipopolysaccharide-stimulated RAW264.7 cells. Notably, the therapeutic effects of retinoic acid were inhibited by MKP-1 knockdown. Retinoic acid exerts a significant therapeutic effect on adjuvant arthritis in mice by regulating macrophage polarization through the MKP-1/MAPK pathway, and play an important role in the treatment of rheumatic diseases.

Result Analysis
Print
Save
E-mail