scholarly journals miR-708 Negatively Regulates TNFα/IL-1β Signaling by Suppressing NF-κB and Arachidonic Acid Pathways

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Nicholas J. Monteleone ◽  
Carol S. Lutz

Two pathways commonly dysregulated in autoimmune diseases and cancer are tumor necrosis factor alpha (TNFα) and interleukin 1 beta (IL-1β) signaling. Researchers have also shown that both signaling cascades positively regulate arachidonic acid (AA) signaling. More specifically, TNFα/IL-1β promotes expression of the prostaglandin E2- (PGE2-) producing enzymes, cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1). Exacerbated TNFα, IL-1β, and AA signaling have been associated with many diseases. While some TNFα therapies have significantly improved patients’ lives, there is still an urgent need to develop novel therapeutics that more comprehensively treat inflammatory-related diseases. Recently, researchers have begun to use RNA interference (RNAi) to treat various diseases in the clinic. One type of RNAi is microRNA (miRNA), a class of small noncoding RNA found within cells. One miRNA in particular, miR-708, has been shown to target COX-2 and mPGES-1. Previous studies have also suggested that miR-708 may be a negative regulator of TNFα/IL-1β signaling. Therefore, we studied the relationship between miR-708, TNFα/IL-1β, and AA signaling in diseased lung cells. We found that miR-708 negatively regulates TNFα/IL-1β signaling in nondiseased lung cells, which is lost in diseased lung cells. Transient transfection of miR-708 suppressed TNFα/IL-1β-induced changes in COX-2, mPGES-1, and PGE2 levels. Moreover, miR-708 also suppressed TNFα/IL-1β-induced IL-6 independent of AA signaling. Mechanistically, we determined that miR-708 suppressed IL-6 signaling by reducing expression of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activator inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ). Collectively, our data suggest miR-708 regulates TNFα/IL-1β signaling by inhibiting multiple points of the signaling cascade.

2021 ◽  
Vol 14 ◽  
Author(s):  
Gaber F. Ali ◽  
Hany A. Omar ◽  
Fatema Hersi ◽  
Amira M. Abo-Youssef ◽  
Osama M. Ahmed ◽  
...  

Background: Liver cancer ranks as the 7th and 5th leading cause of cancer morbidity worldwide in men and women, respectively. Hepatocellular carcinoma (HCC) is the most common type of liver cancer and is associated with an increasing global burden of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Objective: The present study aimed to investigate the possible chemopreventive effect of etoricoxib on diethylnitrosamine (DENA) and 2-acetylaminofluorene (2AAF)-induced HCC in male Wistar rats. Methods: HCC was induced by DENA (150 mg/kg/week; i.p) for 2 weeks, then 2AAF (20 mg/kg; p.o) every other day for three successive weeks. Etoricoxib (0.6 mg/kg, p.o.) was given to DENA/2AAF-administered rats for 20 weeks. Results: Etoricoxib significantly suppressed alpha-fetoprotein (AFP) and carbohydrate antigen 19-9 (CA19.9) as liver tumor biomarkers. It also decreased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin levels while increasing serum albumin levels. Besides, it alleviated DENA/2AAF-induced histopathological abrasions and inflammatory cell infiltration. Furthermore, etoricoxib showed a potent antioxidant effect, supported by a significant lipid peroxide reduction and elevation in superoxide dismutase and GSH content activity. In addition, Etoricoxib significantly down-regulated the protein expression of interleukin 1 beta (IL-1β), tumor necrosis factor α (TNFα), nuclear Factor-kappa B (NF-κB), phosphorylated nuclear Factor-kappa B (p-NF-κB), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2). Conclusion: In conclusion, the current results proved that etoricoxib possesses an anticarcinogenic effect via its antioxidant, anti-inflammatory, and modulation of NF-κB/COX-2/PGE2 signaling.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Megumi Kobayashi ◽  
Kenta Watanabe ◽  
Satoshi Yokoyama ◽  
Chiho Matsumoto ◽  
Michiko Hirata ◽  
...  

Capsaicin, a transient receptor potential vanilloid type 1 (TRPV1) ligand, regulates nerve-related pain-sensitive signals, inflammation, and cancer growth. Capsaicin suppresses interleukin-1-induced osteoclast differentiation, but its roles in bone tissues and bone diseases are not known. This study examined the effects of capsaicin on inflammatory bone resorption and prostaglandin E (PGE) production induced by lipopolysaccharide (LPS) in vitro and on bone mass in LPS-treated mice in vivo. Capsaicin suppressed osteoclast formation, bone resorption, and PGE production induced by LPS in vitro. Capsaicin suppressed the expression of cyclooxygenase-2 (COX-2) and membrane-bound PGE synthase-1 (mPGES-1) mRNAs and PGE production induced by LPS in osteoblasts. Capsaicin may suppress PGE production by inhibiting the expression of COX-2 and mPGES-1 in osteoblasts and LPS-induced bone resorption by TRPV1 signals because osteoblasts express TRPV1. LPS treatment markedly induced bone loss in the femur in mice, and capsaicin significantly restored the inflammatory bone loss induced by LPS in mice. TRPV1 ligands like capsaicin may therefore be potentially useful as clinical drugs targeting bone diseases associated with inflammatory bone resorption.


1997 ◽  
Vol 53 (2) ◽  
pp. 149-160 ◽  
Author(s):  
Patricia Renard ◽  
Marie-Denise Zachary ◽  
Catherine Bougelet ◽  
Marc-Edouard Mirault ◽  
Guy Haegeman ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Xingyong Chen ◽  
Xiaogeng Shi ◽  
Xu Zhang ◽  
Huixin Lei ◽  
Simei Long ◽  
...  

Hypertension is associated with low-grade inflammation, and Toll-like receptor 4 (TLR4) has been shown to be linked to the development and maintenance of hypertension. This study aimed to investigate the effects of scutellarin (administered by oral gavage daily for 2 weeks) on brain TLR4/nuclear factor kappa B-(NF-κB-) mediated inflammation and blood pressure in renovascular hypertensive (using the 2-kidney, 2-clip method) rats. Immunofluorescence and western immunoblot analyses revealed that hypertension contributed to the activation of TLR4 and NF-κB, accompanied by significantly enhanced expression of proinflammatory mediators, such as tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), and interleukin-18 (IL-18). Furthermore, expression of the antiapoptotic protein, myeloid cell leukemia-1 (Mcl1), was decreased, and the pro-apoptotic proteins, Bax and cleavedcaspase-3 p17 were increased in combined cerebral cortical/striatal soluble lysates. Scutellarin significantly lowered blood pressure and attenuated the number of activated microglia and macrophages in brains of hypertensive rats. Furthermore, scutellarin significantly reduced the expression of TLR4, NF-κB p65, TNF-α, IL-1β, IL-18, Bax and cleaved-caspase-3 p17, and increased the expression of Mcl1. Overall, these results revealed that scutellarin exhibits anti-inflammatory and anti-apoptotic properties and decreases blood pressure in hypertensive rats. Therefore, scutellarin may be a potential therapeutic agent in hypertension-associated diseases.


2003 ◽  
Vol 228 (7) ◽  
pp. 786-794 ◽  
Author(s):  
Wieslaw Kozak ◽  
David M. Aronoff ◽  
Olivier Boutaud ◽  
Anna Kozak

Cytochrome P-450 monooxygenase (epoxygenase)-derived arachidonic acid (AA) metabolites, including 11,12-epoxyeicosatrienoic acid (11,12-EET), possess anti-inflammatory and antipyretic properties. Prostaglandin E2 (PGE2), a cyclooxygenase (COX)-derived metabolite of AA, is a well-defined mediator of fever and inflammation. We have tested the hypothesis that 11,12-EET attenuates synthesis of PGE2 in monocytes, which are the cells that are indispensable for induction of fever and initiation of inflammation. Monocytes isolated from freshly collected rat blood were stimulated with lipopolysaccharide (LPS; 100 ng/2 × 105 cells) to induce COX-2 and stimulate generation of PGE2. SKF-525A, an inhibitor of epoxygenases, significantly augmented the lipopolysaccharide-provoked synthesis of PGE2 in cell culture in a concentration-dependent manner. It did not affect, however, elevation of the expression of COX-2 protein in monocytes stimulated with LPS. 11,12-EET also did not affect the induction of COX-2 in monocytes incubated with lipopolysaccharide. However, 11,12-EET suppressed, in a concentration-dependent fashion, the generation of PGE2 in incubates. Preincubation of a murine COX-2 preparation for 0–5 min with three concentrations of 11,12-EET (1, 5, and 10 μM) inhibited the oxygenation of [14C]-labeled AA by the enzyme. The inhibitory effect of 11,12-EET on COX-2 was time-and-concentration-dependent, suggesting a mechanism-based inhibition. Based on these data, we conclude that 11,12-EET suppresses generation of PGE2 in monocytes via modulating the activity of COX-2. These data support the hypothesis that epoxygenasederived AA metabolites constitute a negative feedback on the enhanced synthesis of prostaglandins upon inflammation.


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