Effect of VEGFC on lymph flow and inflammation-induced alveolar bone loss.

The lymphatic system plays a crucial role in the maintenance of tissue fluid homeostasis and the immunological response to inflammation. The effects of lymphatic drainage dysfunction on periodontitis have not been well studied. Here we show that lymphatic vessel endothelial receptor 1 (LYVE1)+ /podoplanin (PDPN)+ lymphatic vessels (LVs) are increased in the periodontal tissues, with accumulation close to the alveolar bone surface, in two murine periodontitis models: rheumatoid arthritis (RA)-associated periodontitis and ligature-induced periodontitis. Further, PDPN+ /alpha-smooth muscle actin (αSMA)- lymphatic capillaries are increased, whereas PDPN+ /αSMA+ collecting LVs are decreased significantly in the inflamed periodontal tissues. Both mouse models of periodontitis have delayed lymph flow in periodontal tissues, increased TRAP-positive osteoclasts, and significant alveolar bone loss. Importantly, the local administration of adeno-associated virus for vascular endothelial growth factor C, the major growth factor that promotes lymphangiogenesis, increases the area and number of PDPN+ /αSMA+ collecting LVs, promotes local lymphatic drainage, and reduces alveolar bone loss in both models of periodontitis. Lastly, LYVE1+ /αSMA- lymphatic capillaries are increased, whereas LYVE1+ /αSMA+ collecting LVs are decreased significantly in gingival tissues of patients with chronic periodontitis compared with those of clinically healthy controls. Thus, our findings reveal an important role of local lymphatic drainage in periodontal inflammation-mediated alveolar bone loss. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The gut-joint axis mediates the TNF-induced RA process and PBMT therapeutic effects through the metabolites of gut microbiota.

The gut-joint axis, one of the mechanisms that mediates the onset and progression of joint and related diseases through gut microbiota, and shows the potential as therapeutic target. A variety of drugs exert therapeutic effects on rheumatoid arthritis (RA) through the gut-joint axis. However, the anti-inflammatory and immunomodulatory effect of novel photobiomodulatory therapy (PBMT) on RA need further validation and the involvement of gut-joint axis in this process remains unknown. The present study demonstrated the beneficial effects of PBMT on RA, where we found the restoration of gut microbiota homeostasis, and the related key pathways and metabolites after PBMT. We also discovered that the therapeutic effects of PBMT on RA mainly through the gut-joint axis, in which the amino acid metabolites (Alanine and N-acetyl aspartate) play the key role and rely on the activity of metabolic enzymes in the target organs. Together, the results prove that the metabolites of amino acid from gut microbiota mediate the regulation effect on the gut-joint axis and the therapeutic effect on rheumatoid arthritis of PBMT.

Huangqi Guizhi Wuwu Decoction Improves Arthritis and Pathological Damage of Heart and Lung in TNF-Tg Mice.

Background: Huangqi Guizhi Wuwu Decoction (HGWD) is a traditional and effective Chinese medicine compound decoction for the treatment of rheumatoid arthritis (RA). However, there is few research on the treatment of rheumatoid cardiopulmonary complications. The present study was to study whether HGWD can alleviate the pathological changes caused by rheumatoid arthritis and cardiopulmonary complications. Methods: Five 3-month-old TNF-Tg mice were treated with HGWD (9.1 g/kg) once a day or the same dose of normal saline lasted for 8 weeks, and wild-type littermates of the same age were used as a negative control, and methotrexate (MTX) was intraperitoneally administered as a positive control. After the treatment, pathological staining was performed on the mouse ankle joints, heart, and lungs. Result: It was found that HGWD reduced the inflammation of the ankle joint synovium in TNF-Tg mice, and reduced myocardial hypertrophy, inflammatory infiltration and fibrosis of heart, as well as lung inflammation and fibrosis. Immunohistochemical staining with anti-TNF-α antibody showed that HGWD reduced the expression of TNF-α in the heart of TNF-Tg mice. Conclusion: In conclusion, HGWD alleviates joint inflammation in TNF-Tg mice and reduces the pathological changes of the heart and lungs.

Notoginsenoside R1 (NG-R1) Promoted Lymphatic Drainage Function to Ameliorating Rheumatoid Arthritis in TNF-Tg Mice by Suppressing NF-κB Signaling Pathway.

Rheumatoid arthritis (RA) is a chronic autoimmune disease that is primarily characterized by synovial inflammation. Our previous studies demonstrated that the lymphatic system is critical for the development and maintenance of RA disease, and sufficient lymph drainage helps to improve joint inflammation. In this study, we found that NG-R1, the main active component in the traditional Chinese medicinal herb Sanchi, activating lymphatic function can attenuate synovial inflammation. According to histopathological staining of ankle sections, NG-R1 significantly decreased the area of inflammation and reduced bone destruction of ankle joints in TNF-Tg mice. Near infrared-indocyanine green (NIR-ICG) lymphatic imaging system has shown that NG-R1 significantly improved the lymphatic drainage function. However, the molecular mechanism of its activity is not properly understood. Our in-depth study demonstrates that NG-R1 reduced the inflammatory cytokine production of lymphatic endothelial cells (LECs) stimulated by TNF-α, and the mechanism ameliorated the phosphorylation of IKKα/ß and p65, and the translocation of p65 into the nucleus. In summary, this study proved that NG-R1 promoted lymphatic drainage function to ameliorating rheumatoid arthritis in TNF-Tg mice by suppressing NF-κB signaling pathway.

Study on the efficacy and mechanism of triptolide on treating TNF transgenic mice with rheumatoid arthritis.

OBJECTIVE: To discuss the curative effect and security of triptolide (TPL) on TNF transgenic (TNF-Tg) mice with rheumatoid arthritis (RA), and to explore the mechanism primarily. METHOD: 40 TNF-Tg RA mice were randomlydivided into five groups averagely: the control group, low-dose group (3.3 µg/kg/d TPL), middle-dose group (10 µg/kg/d TPL), high-dose group (33 µg/kg/d TPL) and MTX group (0.1 mg/kg/d MTX). Mice were administrated five days a week for six weeks. The arthritis deformation index, arthritis detumescencepercentage and the level of inflammatory factor in each group were recorded during theadministration. After administration, body weight, liver and renal function indexes, the apoptosis rates of osteoclast precursors (OCP), T and B lymphocytes in the peripheral blood and the number of osteoclast (OC) were detected and compared. µCT scanning and HE staining methods were taken to observethebone histomorphometry and bony erosion. RESULT: After administration, the arthritis deformation indexes were lower and arthritis detumescence percentageswere higher in TPL groups thanthe control group (P < 0.05), and the arthritis detumescence percentage in the high-dose group was higher than the MTX group (P < 0.05). The liver function index ALT increased after administrationin the high-dose group but was lower than that in the MTX group (P < 0.05). The level of IL-1α, IL-1ß, and TNF-α decreased in the TPL groups and MTX group after administration;The apoptosis rates of OCP and T lymphocytes in middle and high dose TPL groups and MTX group were higher than other groups, and that in the high-dose group was higher than the MTX group (P < 0.05). Compared with the other groups, the bony erosion degree was lower and the number of OC was less and the parameters of bone histomorphometry were better in the high-dose group. CONCLUSION: TPL could improvearthritic of TNF-Tg mice by decreasing the levels of pro-inflammatory cytokines, promoting the apoptosis of OCP, inhibiting the generation of OC and bone resorption. There was some toxic and side effect on liver for high-dose TPL which was weaker than the MTX.

Mechanisms Behind the Therapeutic Effects of Er Chen Combined with Tao Hong Si Wu Tang (ECSWT) on Rheumatoid Arthritis / 世界科学技术-中医药现代化

Rheumatoid arthritis (RA) is a chronic autoimmune disorder primarily occurred in small joints.Our previous studies suggested that sufficient lymphatic drainage was favorable for the recovery of RA.This study aimed at exploring the effect of Er Chen combined with Tao Hong Si Wu Tang (ECSWT) on RA in TNF transgenic (TNF-Tg) mice.Ten-week old TNF-Tg mice and WT littermates were detected with indocyanine green-nearinfrared (ICG-NIR) lymphatic imaging system before and after accepting the 12-week intragastric administration of ECSWT.All ankle joints were assessed by micro-CT scanning.According to three dimensional images of Micro-CT,it was found that the ankle joints in the TNF-Tg group were much eroded compared with the control group.The bone mass and structure were protected after the treatment of ECSWT.ICG-NIR results showed that lymphatic clearance rate of the TNF-Tg group decreased compared with those of the control group.In comparison with the TNF-Tg group,ECSWT promoted the repair of lymphatic function.Compared with the control group,the pulse value of the TNF-Tg group declined;while this condition could be rescued by ERSWT.In conclusion,ECSWT mitigated bone erosion of astragalus bone area in TNF-Tg mice in contrast to the saline mice,while promoted the pulse value and clearance of lymphatic vessels afferent from footpad to popliteal lymph node,implying that ECSWT was a promising agent for treating RA through its promoting lymphatic drainage function effects.