scholarly journals 885 The secretion of TNF-α by inflammatory macrophages has dual effects on subcutaneous adipose precursor cells: inhibition of differentiation and activation of proliferation

2019 ◽  
Vol 139 (5) ◽  
pp. S153
Author(s):  
S. Yoshimoto ◽  
N. Sato ◽  
N. Kohara ◽  
K. Eguchi ◽  
Y. Tsuruta ◽  
...  
2016 ◽  
Vol 36 (1) ◽  
Author(s):  
Abbas Jawad Al-Shabany ◽  
Alan John Moody ◽  
Andrew David Foey ◽  
Richard Andrew Billington

Bacterial lipopolysaccharide induces changes in intracellular NAD+ levels in a pro-inflammatory, but not an anti-inflammatory, macrophage model that are correlated with the release of the pro-inflammatory cytokine tumour necrosis factor-α (TNF-α).


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Junyu Shi ◽  
Yi Zhang ◽  
Xiaomeng Zhang ◽  
Ruiying Chen ◽  
Jianxu Wei ◽  
...  

Abstract Background Periodontitis is a complicated inflammatory disease that damages the tooth-supporting tissues, with limited pharmacotherapy available. Macrophage-targeting therapy is promising for inflammatory diseases. Resveratrol (RSV), a nonflavonoid polyphenol, is known for its anti-inflammatory and immunomodulatory effects. However, its medical application is limited by its poor stability and water-solubility, as well as its low bioavailability. Result A therapeutic resveratrol-loaded liposomal system (Lipo-RSV) was developed to treat periodontitis. The physical properties of Lipo-RSV and its ability to regulate macrophages were investigated. The results showed that Lipo-RSV had good biocompatibility and could re-educate the inflammatory macrophages from M1- to M2-like phenotype through activating p-STAT3 and downregulating p-STAT1. Besides, the Lipo-RSV could scavenge ROS and inhibit the NF-κB signal and inflammasomes, thereby reducing the pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. Conclusion These results revealed that Lipo-RSV could be a potential therapeutic system for the antibiotic-free treatment for periodontal diseases. Graphical Abstract


Cells ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 42
Author(s):  
Simona Cataldi ◽  
Marianna Aprile ◽  
Daniela Melillo ◽  
Inès Mucel ◽  
Sophie Giorgetti-Peraldi ◽  
...  

Low-grade chronic inflammation and reduced differentiation capacity are hallmarks of hypertrophic adipose tissue (AT) and key contributors of insulin resistance. We identified PPARGΔ5 as a dominant-negative splicing isoform overexpressed in the AT of obese/diabetic patients able to impair adipocyte differentiation and PPARγ activity in hypertrophic adipocytes. Herein, we investigate the impact of macrophage-secreted pro-inflammatory factors on PPARG splicing, focusing on PPARGΔ5. We report that the epididymal AT of LPS-treated mice displays increased PpargΔ5/cPparg ratio and reduced expression of Pparg-regulated genes. Interestingly, pro-inflammatory factors secreted from murine and human pro-inflammatory macrophages enhance the PPARGΔ5/cPPARG ratio in exposed adipogenic precursors. TNFα is identified herein as factor able to alter PPARG splicing—increasing PPARGΔ5/cPPARG ratio—through PI3K/Akt signaling and SRp40 splicing factor. In line with in vitro data, TNFA expression is higher in the SAT of obese (vs. lean) patients and positively correlates with PPARGΔ5 levels. In conclusion, our results indicate that inflammatory factors secreted by metabolically-activated macrophages are potent stimuli that modulate the expression and splicing of PPARG. The resulting imbalance between canonical and dominant negative isoforms may crucially contribute to impair PPARγ activity in hypertrophic AT, exacerbating the defective adipogenic capacity of precursor cells.


2019 ◽  
Author(s):  
Shanshan Qi ◽  
Yongkui Li ◽  
Zheng Dai ◽  
Mengxi Xiang ◽  
Guobin Wang ◽  
...  

2005 ◽  
Vol 288 (4) ◽  
pp. E741-E747 ◽  
Author(s):  
Tongjian You ◽  
Rongze Yang ◽  
Mary F. Lyles ◽  
Dawei Gong ◽  
Barbara J. Nicklas

Adipose tissue is a major source of inflammatory and thrombotic cytokines. This study investigated the relationship of abdominal subcutaneous adipose tissue cytokine gene expression to body composition, fat distribution, and metabolic risk during obesity. We determined body composition, abdominal fat distribution, plasma lipids, and abdominal subcutaneous fat gene expression of leptin, TNF-α, IL-6, PAI-1, and adiponectin in 20 obese, middle-aged women (BMI, 32.7 ± 0.8 kg/m2; age, 57 ± 1 yr). A subset of these women without diabetes ( n = 15) also underwent an OGTT. In all women, visceral fat volume was negatively related to leptin ( r = −0.46, P < 0.05) and tended to be negatively related to adiponectin ( r = −0.38, P = 0.09) gene expression. Among the nondiabetic women, fasting insulin ( r = 0.69, P < 0.01), 2-h insulin ( r = 0.56, P < 0.05), and HOMA index ( r = 0.59, P < 0.05) correlated positively with TNF-α gene expression; fasting insulin ( r = 0.54, P < 0.05) was positively related to, and 2-h insulin ( r = 0.49, P = 0.06) tended to be positively related to, IL-6 gene expression; and glucose area ( r = −0.56, P < 0.05) was negatively related to, and insulin area ( r = −0.49, P = 0.06) tended to be negatively related to, adiponectin gene expression. Also, adiponectin gene expression was significantly lower in women with vs. without the metabolic syndrome (adiponectin-β-actin ratio, 2.26 ± 0.46 vs. 3.31 ± 0.33, P < 0.05). We conclude that abdominal subcutaneous adipose tissue expression of inflammatory cytokines is a potential mechanism linking obesity with its metabolic comorbidities.


2019 ◽  
Author(s):  
Yu Zhang ◽  
Chengzhe Yang ◽  
Shaohua Ge ◽  
Limei Wang ◽  
Jin Zhang ◽  
...  

Abstract Low concentrations of tumor necrosis factor-alpha and its receptor TNFR2 are both reported to promote osteogenic differentiation of osteoblast precursor cells. Moreover, low concentrations of TNF-α up-regulate the expression of EphB4. However, the molecular mechanisms underlying TNF-α-induced osteogenic differentiation and the roles of TNFR2 and EphB4 have not been fully elucidated. This study showed that with increase in ALP activity, mRNA and protein expression of Runx2, BSP and EphB4, TNFR2 expression was significantly promoted under 0.5 ng/ml TNF-α stimulation in osteoblast precursor cells MC3T3-E1. After TNFR2 was inhibited by gene knockdown with lentivirus-mediated shRNA interference or by a neutralizing antibody against TNFR2, the pro-osteogenic effect of TNF-α was partly reversed, but up-regulation of EphB4 by TNF-α kept unchanged. With EphB4 forward signaling suppressed by a potent inhibitor of EphB4 auto-phosphorylation, NVP-BHG712, TNF-α-enhanced expressions of TNFR2, BSP and Runx2 were significantly decreased. Further investigation into the signaling pathways revealed that TNF-α significantly augmented expression of p-JNK, p-Erk and p-p38, however, only p-Erk expression was significantly inhibited in TNFR2-knockdown cells. In addition, the Erk pathway inhibitor, U0126 (10μM), significantly inhibited the protein levels of Runx2 and BSP when compared with cells treated with TNF-α only. In conclusion, the EphB4, TNFR2 and Erk/MAPK signaling pathway comprise a signaling axis to mediate the positive effect of TNF-α on osteogenic differentiation.


2013 ◽  
Vol 46 (02) ◽  
pp. 94-99
Author(s):  
S. Tiwari ◽  
B. Paul ◽  
S. Kumar ◽  
A. Chandra ◽  
S. Dhananjai ◽  
...  

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