TNF-α signalling and inflammation: interactions between old acquaintances

Abstract

This review concisely summarizes the role of this pro-inflammatory cytokine during inflammation. It is focused mainly on TNF-α intracellular signaling and its influence on the typical inflammatory features in the organism. Being one of the most important pro-inflammatory cytokines, TNF-α participates in vasodilatation and edema formation, and leukocyte adhesion to epithelium through expression of adhesion molecules; it regulates blood coagulation, contributes to oxidative stress in sites of inflammation, and indirectly induces fever. The connection between TNF-α and cancer is mentioned as well.

Turkish Scorzonera Species Extracts Attenuate Cytokine Secretion via Inhibition of NF-κB Activation, Showing Anti-Inflammatory Effect in Vitro

“…3 were (S. tomentosa) selected as representative for analysis of Ex. 1-8, and as visible from the Figure 4, compounds 1-8 (7) and chlorogenic acid (8)] are the main UV-detectable substances observable, which have been later isolated as the major compounds from S. latifolia aerial part. According to our knowledge, this is the first phytochemical study related S. latifolia aerial part and isolation of swertisin (4) as well as 7-methylisoorientin (5) from Scorzonera species.…”

“…As visible, with exception of 8, all phenolics identified in Scorzonera aerial part extracts are glycosides, in majority flavonoids. The presence of all these compounds (1)(2)(3)(4)(5)(6)(7)(8) in the most active extracts (Ex. 1 and Ex.…”

“…The greatest effect on the NF-κB pathway was observed after the treatment of cells with S. tomentosa extract (Ex. 3), which contain the highest amounts of chlorogenic acid (8) and hyperoside (2) among investigated extracts. From the above mentioned, we suggested that chlorogenic acid (8), derivatives of dicaffeoyl-quinic acid (6 and 7), and flavonoids, especially quercetin-3-O-β-D-glucoside (1) and hyperoside (2) could be responsible for the anti-inflammatory activity of tested extracts.…”

“…HPLC analytical method previously published by [22] was optimized and composition of the extracts was tested qualitatively to select main compounds for activity testing. According to this and previous work, eight phenolics: quercetin-3-O-β-D-glucoside (1), hyperoside (2), hydrangenol-8-O-glucoside (3), swertisin (4), 7-methylisoorientin (5), 4,5-O-dicaffeoyl-quinic acid (6), 3,5-O-dicaffeoyl-quinic acid (7), and chlorogenic acid (8), which were isolated as the major phenolic compounds in current study, and terpenoids 9-16, which have been isolated previously [taraxasterol acetate (9), lupeol (10), lupeol acetate (11), β-sitosterol (12), 3-β-hydroxy-fern-8-en-7-one-acetate (13), urs-12-en-11-one-3-acetyl (14), 3-β-hydroxy-fern-7-en-6-one-acetate (15), and olean-12-en-11-one-3-acetyl (16)] were also tested for their inhibitory effects on the TNF-α and IL-1β production.…”

“…They may also directly modulate neutrophil functions across the vascular endothelium [6]. TNF-α, which is reported as a key cytokine in the inflammation, has a wide range of functions for maintaining the normal cellular physiology such as triggering of apoptosis, influence on secretion of cytokines e.g., IL-1, IL-6 and IL-10 as well as activation of T cells and other inflammatory cells [3,8]. TNF-α also causes further activation of the transcription factors NF-κB [9] which regulates about 200 immune, growth, and inflammation-related genes [4].…”