scholarly journals L-Theanine Reduced the Development of Knee Osteoarthritis in Rats via Its Anti-Inflammation and Anti-Matrix Degradation Actions: In Vivo and In Vitro Study

Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1988 ◽  
Author(s):  
Hui Bai ◽  
Zhiheng Zhang ◽  
Yue Li ◽  
Xiaopeng Song ◽  
Tianwen Ma ◽  
...  

The etiology of osteoarthritis (OA) is multifactorial, with no effective disease-modifying-drugs. L-theanine has been reported to inhibit inflammatory responses in some diseases and this study aimed to investigate the effect of L-theanine on Interleukin-1(IL-1)β-stimulated chondrocytes, and in an injury-induced OA rat model. Primary chondrocytes were stimulated by IL-1β (10 ng/mL) for 24 h and then co-cultured with L-theanine for 24 h. The effects of L-theanine on IL-1β-stimulated expression of pro-inflammatory cytokines and hydrolytic enzyme were analyzed using Western blotting, quantitative polymerase chain reaction (q-PCR) and enzyme-linked immunosorbent assay (ELISA) kits. An immunofluorescence assay was used to detect nuclear factor kappa B (NF-κB) phosphorylation. OA was induced by anterior cruciate ligament transection (ACLT) surgery in rats and celecoxib was used as a positive control. OA severity was measured using the Osteoarthritis Research Society International (OARSI) grading system to describe histological changes. The results showed that L-theanine decreased the expression of pro-inflammatory mediators, including cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE-2), inducible nitric oxide synthase (iNOS), and nitric oxide (NO), both in vivo and in vitro. L-theanine treatment inhibited IL-1β-induced upregulation of matrix metalloproteinases (MMP)-3 and MMP-13, as well as inhibited NF-κB p65 activation. In vivo animal model showed that L-theanine administration (200 mg/kg) significantly alleviated OA lesions and decreased OARSI score. Our data indicated that L-theanine decreased inflammatory cytokines and protected extracellular matrix degradation through inhibition of the NF-κB pathway, and L-theanine may be considered a promising therapeutic strategy in OA prevention.

2021 ◽  
Author(s):  
Cheng Ding ◽  
Chuang Yang ◽  
Tao Cheng ◽  
Xingyan Wang ◽  
Qiaojie Wang ◽  
...  

Abstract Background:Inflammatory osteolysis is a major complication of total joint replacement surgery that can cause prosthesis failure and necessitate revision surgery. Macrophages are key effector immune cells in inflammatory responses, but excessive M1-polarization of dysfunctional macrophages leads to the secretion of pro-inflammatory cytokines and severe loss of bone tissue. Here, we report the development of macrophage-biomimetic porous SiO2-coated ultrasmall Se particles (Porous Se@SiO2 nanospheres) for the management of inflammatory osteolysis. Results: Macrophage-membrane-coated porous Se@SiO2 nanospheres(M-Se@SiO2) can attenuate lipopolysaccharide (LPS)-induced inflammatory osteolysis by a dual-immunomodulatory effect. As macrophage membrane decoys, these nanoparticles reduce toxin levels and neutralize pro-inflammatory cytokines. Moreover, the release of Se can induce the polarization of macrophages toward the anti-inflammatory M2-phenotype. These effects are mediated via the inhibition of p65, p38, and extracellular signal-regulated kinase(ERK) signaling. Additionally, the immune environment created by M-Se@SiO2 reduces the inhibition of osteogenic differentiation caused by pro-inflammation cytokines, confirmed through in vitro and in vivo experiments.Conclusion: Our findings suggest that M-Se@SiO2 has an immunomodulatory role in LPS-induced inflammation and bone remodeling, which demonstrates that M-Se@SiO2 is a promising engineered nano-platform for the treatment of osteolysis arising after arthroplasty.


2019 ◽  
Vol 20 (14) ◽  
pp. 3574 ◽  
Author(s):  
Hye-Sun Lim ◽  
Yu Jin Kim ◽  
Bu-Yeo Kim ◽  
Soo-Jin Jeong

The purpose of the present study was to evaluate the effects of bakuchiol on the inflammatory response and to identify the molecular mechanism of the inflammatory effects in a lipopolysaccharide (LPS)-stimulated BV-2 mouse microglial cell line and mice model. The production of prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay. The mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), TNF-α, and IL-6 was measured using reverse transcription–polymerase chain reaction analysis. Mitogen-activated protein kinase (MAPK) phosphorylation was determined by western blot analysis. In vitro experiments, bakuchiol significantly suppressed the production of PGE2 and IL-6 in LPS-stimulated BV-2 cells, without causing cytotoxicity. In parallel, bakuchiol significantly inhibited the LPS-stimulated expression of iNOS, COX-2, and IL-6 in BV-2 cells. However, bakuchiol had no effect on the LPS-stimulated production and mRNA expression of TNF-α or on LPS-stimulated c-Jun NH2-terminal kinase phosphorylation. In contrast, p38 MAPK and extracellular signal-regulated kinase (ERK) phosphorylation were inhibited by bakuchiol. In vivo experiments, Bakuchiol reduced microglial activation in the hippocampus and cortex tissue of LPS-injected mice. Bakuchiol significantly suppressed LPS-injected production of TNF-α and IL-6 in serum. These results indicate that the anti-neuroinflammatory effects of bakuchiol in activated microglia are mainly regulated by the inhibition of the p38 MAPK and ERK pathways. We suggest that bakuchiol may be beneficial for various neuroinflammatory diseases.


Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3508
Author(s):  
Yukiko Takahashi ◽  
Takeshi Kawasaki ◽  
Hironori Sato ◽  
Yoshinori Hasegawa ◽  
Steven M. Dudek ◽  
...  

Excessive inflammation in the lung is a primary cause of acute respiratory distress syndrome (ARDS). CD26/dipeptidyl peptidase-4 (DPP4) is a transmembrane protein that is expressed in various cell types and exerts multiple pleiotropic effects. We recently reported that pharmacological CD26/DPP4 inhibition ameliorated lipopolysaccharide (LPS)-induced lung injury in mice and exerted anti-inflammatory effects on human lung microvascular endothelial cells (HLMVECs), in vitro. However, the mechanistic roles of CD26/DPP4 in lung injury and its effects on HLMVECs remain unclear. In this study, transcriptome analysis, followed by various confirmation experiments using siRNA in cultured HLMVECs, are performed to evaluate the role of CD26/DPP4 in response to the pro-inflammatory involved in inflammation, barrier function, and regenerative processes in HLMVECs after pro-inflammatory stimulation. These are all functions that are closely related to the pathophysiology and repair process of lung injury. Confirmatory experiments using flow cytometry; enzyme-linked immunosorbent assay; quantitative polymerase chain reaction; dextran permeability assay; WST-8 assay; wound healing assay; and tube formation assay, reveal that the reduction of CD26/DPP4 via siRNA is associated with altered parameters of inflammation, barrier function, and the regenerative processes in HLMVECs. Thus, CD26/DPP4 can play a pathological role in mediating injury in pulmonary endothelial cells. CD26/DPP4 inhibition can be a new therapeutic strategy for inflammatory lung diseases, involving pulmonary vascular damage.


2021 ◽  
Author(s):  
xiuli zhang ◽  
Dahua Wu ◽  
Dandan Li ◽  
Jian Liu ◽  
Chang Lei ◽  
...  

Abstract Background Zuogui Jiangtang Jieyu formulation (ZGJTJY) is a Chinese polyherbal prescription for diabetes-related depression (DD). The mechanism underlying hippocampal M1/M2 polarization in DD and the ZGJTJY treatment effects remain unclear. This study aimed to investigate M1/M2 microglial polarization in the hippocampus of DD rats and HAPI (highly aggressively proliferating immortalized) cells simulating the DD state, as well as to examine the ZGJTJY intervention effects, both in vivo and in vitro. Methods We subjected Sprague Dawley rats to a high-fat diet, streptozotocin, and unpredictable chronic mild stress; subsequently, we orally administered ZGJTJY. HAPI cells were induced using high glucose and corticosterone; subsequently, ZGJTJY-containing serum was added to examine changes in M1/M2 microglial polarization. Moreover, metformin combined with fluoxetine (DMGB/F) was used as a positive drug for evaluating the ZGJTJY intervention. Laser confocal scanning was used to examine the microglial morphology. Further, real-time PCR was used to determine M1 markers (MHCII, iNOS, MCP-1, CD11b), M2 markers (Arg1, Mrc1, Ym1), pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), and anti-inflammatory cytokines (IL-4, IL-10). Additionally, an enzyme-linked immunosorbent assay was used to examine inflammatory cytokines. Results There was significant activation of M1 polarization in the hippocampus of DD rats and HAPI cells induced using high glucose and corticosterone. Compared with DMGB/F, ZGJTJY inhibited and promoted M1 and M2 polarization, respectively; moreover, it decreased the M1-to-M2 polarization ratio both in vivo and in vitro. Conclusions The study indicated that hippocampal M1 polarization is crucially involved in DD pathogenesis; moreover, there is a need for further research on the neuroprotective effect of Chinese medicine associated with M2-polarized microglia.


Author(s):  
Kristin E. D. Weimer ◽  
Hunter Roark ◽  
Kimberley Fisher ◽  
C. Michael Cotten ◽  
David A. Kaufman ◽  
...  

Abstract Objective Very low birth weight preterm infants are at risk for life-threatening infections in the NICU. Breast milk protects against infections but carries the risk of infection by cytomegalovirus (CMV) shed in mother's milk. Lactoferrin is a breast milk and saliva protein with potent neutralizing activity against CMV. Study Design VLBW, maternal breast milk fed infants in the NICU and their lactating mothers were enrolled and followed for 3 months/discharge. Breast milk and infant saliva samples were collected biweekly. Maternal CMV status was determined on breast milk. CMV was measured using quantitative polymerase chain reaction and lactoferrin by enzyme-linked immunosorbent assay. Results In an in vitro neutralization assay, the IC90 of purified human lactoferrin against CMV was 2.08 ng/mL. Bovine lactoferrins were more potent, IC90s > 10-fold higher. Lactoferrin was detected in all breast milk (median: 3.3 × 106 ng/mL) and saliva (median: 84.4 ng/swab) samples. Median CMV load in breast milk was 893 copies/mL. There was no correlation between breast milk lactoferrin concentration and CMV load. Five infants acquired postnatal CMV. There was no difference in saliva or breast milk lactoferrin concentration for mother–infant pairs and postnatal CMV acquisition. Conclusion Lactoferrin neutralizes CMV in vitro, but concentrations in breast milk and saliva are likely too low for effective neutralization in vivo.


Biomolecules ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 611
Author(s):  
Chae Young Lee ◽  
Han Gyung Kim ◽  
Sang Hee Park ◽  
Seok Gu Jang ◽  
Kyung Ja Park ◽  
...  

Alverine, a smooth muscle relaxant, is used to relieve cramps or spasms of the stomach and intestine. Although the effects of alverine on spontaneous and induced contractile activity are well known, its anti-inflammatory activity has not been fully evaluated. In this study, we investigated the anti-inflammatory effects of alverine in vitro and in vivo. The production of nitric oxide (NO) in RAW264.7 cells activated by lipopolysaccharide (LPS) or polyinosinic:polycytidylic acid (poly (I:C)) was reduced by alverine. The mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) was also dose-dependently inhibited by treatment with alverine. In reporter gene assays, alverine clearly decreased luciferase activity, mediated by the transcription factor nuclear factor κB (NF-κB) in TIR-domain-containing adapter-inducing interferon-β (TRIF)- or MyD88-overexpressing HEK293 cells. Additionally, phosphorylation of NF-κB subunits and upstream signaling molecules, including p65, p50, AKT, IκBα, and Src was downregulated by 200 μM of alverine in LPS-treated RAW264.7 cells. Using immunoblotting and cellular thermal shift assays (CETSAs), Src was identified as the target of alverine in its anti-inflammatory response. In addition, HCl/EtOH-stimulated gastric ulcers in mice were ameliorated by alverine at doses of 100 and 200 mg/kg. In conclusion, alverine reduced inflammatory responses by targeting Src in the NF-κB pathway, and these findings provide new insights into the development of anti-inflammatory drugs.


2001 ◽  
Vol 69 (10) ◽  
pp. 6401-6410 ◽  
Author(s):  
Judy M. Hickman-Davis ◽  
J. Russell Lindsey ◽  
Sadis Matalon

ABSTRACT We previously reported that congenic C57BL/6 inducible nitric oxide synthase−/− (iNOS−/−) mice infected withMycoplasma pulmonis developed higher bacterial numbers and lung lesion scores than C57BL/6 iNOS+/+ controls but had similar lung nitrotyrosine levels. The present studies investigated the role of inflammatory cells in nitrotyrosine formation during mycoplasmal infection. iNOS+/+ and iNOS−/−mice were injected with cyclophosphamide (CYP) and inoculated with 107 CFU of M. pulmonis. CYP pretreatment ofM. pulmonis-infected iNOS+/+ and iNOS−/− mice reduced polymorphonuclear cells (PMNs) within bronchoalveolar lavages (BALs) by 88 and 72%, respectively, and whole-lung myeloperoxidase levels by 80 and 78%, respectively, at 72 h postinfection but did not alter the number of alveolar macrophages (AMs) in BALs. CYP treatment also significantly decreased nitrate and nitrite (NOx) levels in BALs and plasma of infected iNOS+/+ mice, whereas neither CYP nor mycoplasmal infection altered NOx in iNOS−/− mice. CYP reduced lung nitrotyrosine levels in both iNOS+/+ and iNOS−/− mice to uninfected-control levels as shown by immunohistochemical staining and enzyme-linked immunosorbent assay and inhibited mycoplasmal killing by iNOS+/+ mice in vivo. CYP inhibited the production of gamma interferon-inducible NOx by iNOS+/+ AMs in vitro but did not alter the number of iNOS-positive AMs, as detected by immunocytochemistry. In addition, AMs from CYP-treated iNOS+/+ mice had significantly decreased ability to kill mycoplasmas in vitro. These results demonstrate that reactive species generated by inflammatory cells as well as PMN myeloperoxidase are important contributors to nitrotyrosine formation during mycoplasmal infection and that treatment with CYP decreases NO⋅ production by AMs and inhibits mycoplasmal killing.


2001 ◽  
Vol 280 (2) ◽  
pp. C280-C287 ◽  
Author(s):  
Cynthia M. Otto ◽  
James E. Baumgardner

Macrophages are commonly cultured at a Po2of 149 Torr, but tissue macrophages in vivo live in an environment of much lower oxygen tension. Despite the many potential mechanisms for changes in oxygen tension to influence nitric oxide (NO) synthesis, there have been few reports investigating the effect of Po2on macrophage NO production. With the use of a culture chamber designed to rigorously control oxygen tension, we investigated the effects of culture Po2on macrophage NO production, inducible nitric oxide synthase (iNOS) activity, iNOS protein, and tumor necrosis factor production. NO production and iNOS activity were linearly related in the range of 39.4 to 677 Torr, but not in the range of 1.03 to 39.4 Torr. Therefore, results obtained in vitro for the high oxygen tensions commonly used in cell culture were quantitatively and qualitatively different from results obtained in cells cultured at the lower oxygen tensions that more accurately reflect the in vivo environment. The influence of oxygen tension on NO production has implications for cell culture methodology and for the relationship between microcirculatory dysfunction and inflammatory responses in rodent models of sepsis.


2020 ◽  
Vol 39 (10) ◽  
pp. 1333-1344
Author(s):  
S Li ◽  
L Jiang ◽  
Y Yang ◽  
J Cao ◽  
Q Zhang ◽  
...  

Chronic obstructive pulmonary disease (COPD), characterized by chronic inflammation, is a recognized global health crisis. Sialic acid-binding immunoglobulin-like lectin 1 (siglec1 or CD169), mainly expressed in macrophages and dendritic cells, is markedly upregulated after encountering pathogens or under acute/chronic inflammation conditions. However, it is rarely reported that whether siglec1 plays a role in the development of COPD. In this study, we found that siglec1 had higher expression in the lungs from COPD rats and in peripheral blood mononuclear cells (PBMCs) from COPD patients. Knockdown of siglec1 in vivo and in vitro dramatically decreased pro-inflammatory cytokines production in pulmonary macrophages and alleviated pulmonary inflammatory responses in COPD rats as well as inactivated nuclear factor kappa B (NF-κB) signaling. In addition, we identified a new microRNA, miR-195-5p, which has never explored in COPD, was lower expressed in COPD rats and PBMC of COPD patients, and could negatively modulate siglec1 expression in macrophages. Moreover, overexpression of miR-195-5p via miR-195-5p mimics in vitro and in vivo could significantly alleviate pro-inflammatory cytokines production in pulmonary macrophages and pulmonary inflammatory responses in COPD rats. Together, our findings suggested that miR-195-5p inhibited the development of COPD via targeting siglec1, which might become a therapeutic target to improve COPD.


2020 ◽  
Author(s):  
Yutian Li ◽  
Shan Deng ◽  
Xiaohong Wang ◽  
Wei Huang ◽  
Jing Chen ◽  
...  

Abstract Aims Cardiac dysfunction is a prevalent comorbidity of disrupted inflammatory homeostasis observed in conditions such as sepsis (acute) or obesity (chronic). Secreted and transmembrane protein 1a (Sectm1a) has previously been implicated to regulate inflammatory responses, yet its role in inflammation-associated cardiac dysfunction is virtually unknown. Methods and results Using the CRISPR/Cas9 system, we generated a global Sectm1a-knockout (KO) mouse model and observed significantly increased mortality and cardiac injury after lipopolysaccharide (LPS) injection, when compared with wild-type (WT) control. Further analysis revealed significantly increased accumulation of inflammatory macrophages in hearts of LPS-treated KO mice. Accordingly, ablation of Sectm1a remarkably increased inflammatory cytokines levels both in vitro [from bone marrow-derived macrophages (BMDMs)] and in vivo (in serum and myocardium) after LPS challenge. RNA-sequencing results and bioinformatics analyses showed that the most significantly down-regulated genes in KO-BMDMs were modulated by LXRα, a nuclear receptor with robust anti-inflammatory activity in macrophages. Indeed, we identified that the nuclear translocation of LXRα was disrupted in KO-BMDMs when treated with GW3965 (LXR agonist), resulting in higher levels of inflammatory cytokines, compared to GW3965-treated WT-cells. Furthermore, using chronic inflammation model of high-fat diet (HFD) feeding, we observed that infiltration of inflammatory monocytes/macrophages into KO-hearts were greatly increased and accordingly, worsened cardiac function, compared to WT-HFD controls. Conclusion This study defines Sectm1a as a new regulator of inflammatory-induced cardiac dysfunction through modulation of LXRα signalling in macrophages. Our data suggest that augmenting Sectm1a activity may be a potential therapeutic approach to resolve inflammation and associated cardiac dysfunction.


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