IL-33 stimulates expression of the GPR84 (EX33) fatty acid receptor gene and of cytokine and chemokine genes in human adipocytes

Expression of GPCR fatty acid sensor/receptor genes in adipocytes is modulated by inflammatory mediators, particularly IL-1β. In this study we examined whether the IL-1 gene superfamily member, IL-33, also regulates expression of the fatty acid receptor genes in adipocytes. Human fat cells, differentiated from preadipocytes, were incubated with IL-33 at three different dose levels for 3 or 24 h and mRNA measured by qPCR. Treatment with IL-33 induced a dose-dependent increase in GPR84 mRNA at 3 h, the level with the highest dose being 13.7-fold greater than in controls. Stimulation of GPR84 expression was transitory; the mRNA level was not elevated at 24 h. In contrast to GPR84, IL-33 had no effect on GPR120 expression. IL-33 markedly stimulated expression of the IL1B, CCL2, IL6, CXCL2 and CSF3 genes, but there was no effect on ADIPOQ expression. The largest effect was on CSF3, the mRNA level of which increased 183-fold over controls at 3 h with the highest dose of IL-33; there was a parallel increase in the secretion of G-CSF protein into the medium. It is concluded that in human adipocytes IL-33, which is synthesised in adipose tissue, has a strong stimulatory effect on the expression of cytokine and chemokine genes, particularly CSF3, and on the expression of GPR84, a pro-inflammatory fatty acid receptor

IL-1β and TNFα inhibit GPR120 (FFAR4) and stimulate GPR84 (EX33) and GPR41 (FFAR3) fatty acid receptor expression in human adipocytes: implications for the anti-inflammatory action of n-3 fatty acids

Regulation of the expression of GPCR fatty acid receptor genes has been examined in human adipocytes differentiated in culture. TNFα and IL-1β induced a marked reduction in GPR120 expression, mRNA level falling 17-fold at 24h in adipocytes incubated with TNFα. In contrast, GPR84 mRNA was dramatically increased by these cytokines (>500-fold for IL-1β at 4h); GPR41 expression was also stimulated. Rosiglitazone did not affect GPR84 expression, but GPR120 and GPR41 expression increased. Dexamethasone, insulin, linoleic and docosahexaenoic acids, and TUG891 (GPR120 agonist) had little effect on GPR120 and GPR84 expression. TUG891 did not attenuate the pro-inflammatory actions of TNFα and IL-1β. Docosahexaenoic acid slightly countered the actions of IL-1β on CCL2, IL6 and ADIPOQ expression, though not on secretion of these adipokines. GPR120 and GP84 gene expression in human adipocytes is highly sensitive to pro-inflammatory mediators; the inflammation-induced inhibition of GPR120 expression may compromise the anti-inflammatory action of GPR120 agonists

PCR arrays indicate that the expression of extracellular matrix and cell adhesion genes in human adipocytes is regulated by IL-1β (interleukin-1β)

The role of IL-1β in regulating the expression of extracellular matrix (ECM) and cell adhesion genes in human adipocytes has been examined. Adipocytes differentiated in culture were incubated with IL-1β for 4 or 24 h and RNA probed with PCR arrays for 84 ECM and cell adhesion genes. Treatment with IL-1β resulted in changes in the expression at one or both time points of ~50% of the genes probed by the arrays, the majority being down-regulated. Genes whose expression was down-regulated by IL-1β included those encoding several collagen chains and integrin subunits. In contrast, IL-1β induced substantial increases (>10-fold) in the expression of ICAM1, VCAM1, MMP1 and MMP3; the secretion of the encoded proteins was also markedly stimulated. IL-1β has a pervasive effect on the expression of ECM and cell adhesion genes in human adipocytes, consistent with the derangement of tissue structure during inflammation in white fat

IL-1β (interleukin-1β) stimulates the production and release of multiple cytokines and chemokines by human preadipocytes

The effect of IL-1β on cytokine and chemokine production by human preadipocytes has been examined. Preadipocytes were incubated with IL-1β and cytokine and chemokine release measured at 24 h by protein arrays, while the expression of cytokine/chemokine genes was assessed by qPCR at 4 and 24 h. IL-1β stimulated the secretion of multiple cytokines/chemokines, including IL-6, IL-8, IL-10, IL-13, MCP-4, TNFα and IP-10. IL-10 was not released by un-stimulated preadipocytes, while IL-6 exhibited the greatest response to IL-1β (453-fold increase). IL-16 and IL-12p40 did not respond to IL-1β. qPCR demonstrated that IL-1β markedly stimulated CCL3, CSF3 and CXCL10expression at 4 h (>900-fold mRNA increase). A time-course indicated that while CCL13 (encoding MCP-4) exhibited minimal basal expression in preadipocytes, expression increased progressively following differentiation. Human preadipocytes are highly sensitive to IL-1β, the cytokine stimulating a major inflammatory response in these cells similar to that in mature adipocytes

PCR array and protein array studies demonstrate that IL-1β (interleukin-1β) stimulates the expression and secretion of multiple cytokines and chemokines in human adipocytes

The role of IL-1β in regulating the expression and secretion of cytokines and chemokines by human adipocytes was examined. Adipocytes were incubated with human IL-1β for 4 or 24 h. The expression of a panel of 84 cytokine/chemokine genes was probed using PCR arrays. IL-1β stimulated the expression of >30 cytokine/chemokine genes on the arrays; 15 showed >100-fold increases in mRNA at 4 or 24 h including CSF3, CXCL1, CXCL2, CXCL12 and IL8. CSF3 exhibited a 10,000-fold increase in mRNA at 4 h. ADIPOQ was among the genes whose expression was inhibited. Protein arrays were used to examine the secretion of cytokines/chemokines from adipocytes. IL-1β stimulated the secretion of multiple cytokines/chemokines including MCP-1, IL-8, IP-10, MIP-1α and MCP-4. The most responsive was IP-10, which exhibited a 5,000-fold increase in secretion with IL-1β. IL-1β is likely to play a substantial role in stimulating the inflammatory response in human adipocytes in obesity

BCG vaccine-induced mucosal humoral immunity in human nasal associated lymphoid tissue

Objectives: Mycobacterium tuberculosis (Mtb) is the causative pathogen of tuberculosis (TB). TB vaccine studies have long been conducted. Since the discovery of the successful intradermally administered Mycobacterium bovis Bacillus Calmette–Guérin (BCG) vaccine against TB, no licensed TB mucosal vaccine has yet been approved. Our research aims to investigate the suitability of human NALT-derived MNCs as an in vitro human cell culture model to explore the mucosal humoral immune responses to the BCG vaccine. Moreover, to assure that BCG vaccine able to induce the different antibody isotypes including IgG, IgM and IgA. Methods: Tonsils from 20 patients who underwent elective tonsillectomies at Madinah Germany Hospital were recruited. Tonsillar mononuclear cells (MNCs) were separated and co-cultured in the presence and absence of the BCG vaccine. ELISA was used to measure BCG-induced IgG, IgM and IgA antibodies in the cell culture supernatants following stimulation and culture. Results: Nasal-associated lymphoid tissue (NALT) cell culture as an in vitro model was successfully used to evaluate the BCG-induced humoral immune response. Significant (p = 0.001, n = 20) levels of specific, anti-TB IgG, IgM, and IgA antibody responses were detected in MNCs stimulated with the BCG vaccine compared with unstimulated MNCs. Significant differences were found between anti-TB antibody classes. Anti-TB IgG antibody was significantly higher (mean = 2.33) than anti-TB IgM (mean = 1.37) antibody (p = 0.0001, n = 20). Anti-TB IgM antibody was significantly higher than IgA (mean = 0.93) antibody (p = 0.0018, n = 20). Conclusions: The current human model will be beneficial for the future comprehensive study of other immune components such as cellular immune responses to the BCG vaccine. The model would be ideal to design, improve and study the possible intranasal use of the BCG vaccine

Development of an electrode immunosensor using carbon nanofibres-gold nanoparticles-mercaptopropionic acid-polyethylenimine for chicken liver containing colistin

Colistin is not approved for use by humans; however, it has been used in veterinary medicine and as an additive in animal feeds for many years. This study aims to develop an amperometric immunosensor to detect colistin in chicken liver. An anti-colistin antibody was immobilised on the screen-printed electrode's surface using CNF/AuNPs/MPA/PEI to develop the immunosensor. With the help of CV measurements, this sensor was used to analyse the electrical and chemical reaction of colistin after being injected into chicken liver. Furthermore, FE-SEM and FTIR characterized the electrode surface throughout the fabrication process. Based on CV analysis, 0.072 μgkg-1 LOD was calculated with R2 value of 0.995. The results of conventional methods were compared to liver samples obtained from commercial sources to validate the immunosensor. In the constructed immunosensor, colistin had a high level of specificity, stable for more than six months despite an 11 % decline in CV current. It is imperative to highlight that the present study did not include a process of recovering colistin drug from liver tissue. This lack constitutes a constraint of our research and is annotated with suggestions for future work

IL-1β and TNFα inhibit GPR120 (<i>FFAR4</i>) and stimulate GPR84 (<i>EX33</i>) and GPR41 (<i>FFAR3</i>) fatty acid receptor expression in human adipocytes: implications for the anti-inflammatory action of <i>n</i>-3 fatty acids

<p>Regulation of the expression of GPCR fatty acid receptor genes has been examined in human adipocytes differentiated in culture. TNFα and IL-1β induced a marked reduction in <i>GPR120</i> expression, mRNA level falling 17-fold at 24 h in adipocytes incubated with TNFα. In contrast, GPR84 mRNA was dramatically increased by these cytokines (>500-fold for IL-1β at 4 h); <i>GPR41</i> expression was also stimulated. Rosiglitazone did not affect <i>GPR84</i> expression, but <i>GPR120</i> and <i>GPR41</i> expression increased. Dexamethasone, insulin, linoleic and docosahexaenoic acids (DHA), and TUG891 (GPR120 agonist) had little effect on <i>GPR120</i> and <i>GPR84</i> expression. TUG891 did not attenuate the pro-inflammatory actions of TNFα and IL-1β. DHA slightly countered the actions of IL-1β on <i>CCL2</i>, <i>IL6</i> and <i>ADIPOQ</i> expression, though not on secretion of these adipokines. <i>GPR120</i> and <i>GP84</i> gene expression in human adipocytes is highly sensitive to pro-inflammatory mediators; the inflammation-induced inhibition of <i>GPR120</i> expression may compromise the anti-inflammatory action of GPR120 agonists.</p

Research update on aflatoxins toxicity, metabolism, distribution, and detection: A concise overview

Serious health risks associated with the consumption of food products contaminated with aflatoxins (AFs) are worldwide recognized and depend predominantly on consumed AF concentration by diet. A low concentration of aflatoxins in cereals and related food commodities is unavoidable, especially in subtropic and tropic regions. Accordingly, risk assessment guidelines established by regulatory bodies in different countries help in the prevention of aflatoxin intoxication and the protection of public health. By assessing the maximal levels of aflatoxins in food products which are a potential risk to human health, it's possible to establish appropriate risk management strategies. Regarding, a few factors are crucial for making a rational risk management decision, such as toxicological profile, adequate information concerning the exposure duration, availability of routine and some novel analytical techniques, socioeconomic factors, food intake patterns, and maximal allowed levels of each aflatoxin in different food products which may be varied between countries