Gold nanoparticles attenuate the interferon-γ induced SOCS1 expression and activation of NF-κB p65/50 activity via modulation of microRNA-155-5p in triple-negative breast cancer cells.

Objective: Triple-negative breast cancer (TNBC) is a very aggressive form of cancer that grows and spreads very fast and generally relapses. Therapeutic options of TNBC are limited and still need to be explored completely. Gold nanoparticles conjugated with citrate (citrate-AuNPs) are reported to have anticancer potential; however, their role in regulating microRNAs (miRNAs) in TNBC has never been investigated. This study investigated the potential of citrate-AuNPs against tumorigenic inflammation via modulation of miRNAs in TNBC cells. Methods: Gold nanoparticles were chemically synthesized using the trisodium-citrate method and were characterized by UV-Vis spectrophotometry and dynamic light scattering studies. Targetscan bioinformatics was used to analyze miRNA target genes. Levels of miRNA and mRNA were quantified using TaqMan assays. The pairing of miRNA in 3'untranslated region (3'UTR) of mRNA was validated by luciferase reporter clone, containing the entire 3'UTR of mRNA, and findings were further re-validated via transfection with miRNA inhibitors. Results: Newly synthesized citrate-AuNPs were highly stable, with a mean size was 28.3 nm. The data determined that hsa-miR155-5p is a direct regulator of SOCS1 (suppressor-of-cytokine-signaling) expression and citrate-AuNPs inhibits SOCS1 mRNA/protein expression via modulating hsa-miR155-5p expression. Transfection of TNBC MDA-MB-231 cells with anti-miR155-5p markedly increased SOCS1 expression (p<0.001), while citrate-AuNPs treatment significantly inhibited anti-miR155-5p transfection-induced SOCS1 expression (p<0.05). These findings were validated by IFN-γ-stimulated MDA-MB-231 cells. Moreover, the data also determined that citrate-AuNPs also inhibit IFN-γ-induced NF-κB p65/p50 activation in MDA-MB-231 cells transfected with anti-hsa-miR155-5p. Conclusion: Newly generated citrate-AuNPs were stable and non-toxic to TNBC cells. Citrate-AuNPs inhibit IFN-γ-induced SOCS1 mRNA/protein expression and deactivate NF-κB p65/50 activity via negative regulation of hsa-miR155-5p. These novel pharmacological actions of citrate-AuNPs on IFN-γ-stimulated TNBC cells provide insights that AuNPs inhibit IFN-γ induced inflammation in TNBC cells by modulating the expression of microRNAs.

Thymoquinone provides structural protection of human hemoglobin against oxidative damage: Biochemical studies.

Hydroxyl radicals (OH.) are one of the most active reactive oxidants recognized for their deleterious effects to cause protein oxidative damage. Thymoquinone, a monoterpene molecule abundantly present in black cumin and known for its pharmacological activities, but its activity against the OH.-induced protein oxidative damage has never been explored. This study determined the therapeutic potential of thymoquinone against OH.-induced oxidative human hemoglobin damage. Novel data demonstrated that thymoquinone provides structural protection of hemoglobin against oxidative damage. Treatment of hemoglobin with OH. induces hypochromicity at 280 and 405 nm, whereas thymoquinone reversed these hypochromic effects. In addition, OH. cause significant reduction in tryptophan fluorescence, however thymoquinone also reversed these damaging effects. Thymoquinone also reduces OH.-induced hydrophobicity and also reduces OH.-induced carbonylation. Moreover, it also inhibits thermal stabilization of OH.-hemoglobin complex. SDS-PAGE of unmodified hemoglobin showed four bands, which disappeared upon OH. treatment and these changes were also retained by thymoquinone. In conclusion, this is the first study that shows the therapeutic potential of thymoquinone against OH.-induced oxidative damage in human hemoglobin.

Absence of CD74 Isoform at 41kDa Prevents the Heterotypic Associations between CD74 and CD44 in Human Lung Adenocarcinoma-derived Cells.

Lung cancer is a leading cause of cancer-associated death in all over the globe. This study was undertaken to determine the expression and interaction of membrane-bound receptors CD74 and CD44 in human lung adenocarcinoma cells and their associated signaling was also attempted. Levels of CD74 and CD44 were studied in human lung adenocarcinoma-evolved cells A549 and H460. CD74-mediated downstream signaling was studied by the nuclear-transcription-factor NF-κB and prostaglandin E2 (PGE2) production. Flow-cytometric analysis showed that both CD74 and CD44 were perfectly expressed in A549 cells. Importantly, Western immunoblotting showed that A549 cells expressed only two isoforms of CD74 at 33 and 35 kDa but isoform at 41 kDa was absent. These results were verified in H460 cells. Confocal microscopy showed CD74 and CD44 was colocalized but heterotypic interaction between them was missing in both A549 and H460 cells. Activation of NF-κB and production of PGE2 in human lung cancer cells were comparable with other cancer cells. In conclusion, this is the first study that shows A549 and H460 cells expressed two distinctive isoforms of CD74 but isoform at 41 kDa was absent. Due to the absence of this isoform, the direct physical interaction between them CD74 and CD44 was lacking. Furthermore, the data also demonstrated that lacking of direct physical interaction between CD74 and CD44 had no effect on NF-κB activation and PGE2 production indicating that CD74-mediated downstream signaling occurs either through coreceptors or indirect interaction with CD44 in human lung cancer cells.Abbreviation: CD: cluster of differentiation; SCLC: small cell lung cancer; NSCLC: nonsmall cell lung cancer; SCC: squamous cell carcinoma; ADC: adenocarcinoma; LCC: large cell carcinoma.

Bisphenol A modified DNA: A possible immunogenic stimulus for anti-DNA autoantibodies in systemic lupus erythematosus.

Anti-DNA antibodies are now considered as a universal diagnostic feature for the patients with systemic lupus erythematosus (SLE) but the mechanism(s) involved in the generation of these autoantibodies remains to be investigated. Bisphenol A (BPA) is a synthetic phenol extensively used in the manufacturing of polycarbonated plastics. Upon mixing in the diet, it causes several health hazards. This study was undertaken to investigate the contribution of BPA induced DNA damage in SLE patients. Human DNA was modified by BPA in-vitro and the binding characteristics of SLE circulating immunoglobulin Gs (SLE-IgGs) with BPA damaged DNA (BPA-DNA) were screened and compared with the IgGs from normal healthy humans (NH-IgGs). Immunogenicity of BPA-DNA was determined by immunisation in rabbits. DNA from SLE patients (SLE-DNA) or healthy humans (NH-DNA) were isolated and their binding specificity with rabbit anti-BPA-DNA-IgGs was studied. Treatment of human DNA with BPA caused extensive damaged. Circulating SLE-IgGs showed strong recognition of BPA-DNA. BPA-DNA induced high titre antibodies in rabbits. Rabbit anti-BPA-DNA-IgGs showed strong cross reaction with isolated DNA from SLE patients. In short, we concluded that the structural alterations in DNA by BPA, generate neo-epitopes that may be a factor responsible for the induction of anti-DNA autoantibodies in SLE.

Author Correction: MicroRNA-125b-5p regulates IL-1ß induced inflammatory genes via targeting TRAF6-mediated MAPKs and NF-κB signaling in human osteoarthritic chondrocytes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Stress Associated Alterations in Dietary Behaviours of Undergraduate Students of Qassim University, Saudi Arabia.

BACKGROUND: Psychological stress associated eating habits among public health have now become a global concern. AIM: This study was undertaken to investigate the levels of psychological stress among undergraduate students of Qassim University and to explore the stress associated alterations in their eating habits. METHODS: This is a cross-sectional survey conducted on 614 undergraduate students of Qassim University, Saudi Arabia. A self-administered questionnaire was used, which included questions on socio-demography and eating habits. Level of stress was measured by a standardised questionnaire highlights the levels of non-chronic stimulation through difficulty relaxing, nervous arousal and being easily upset/agitated, irritable / over-reactive and impatient. RESULTS: Our results show that 28.2% of total participants suffered from some extent of stress. Among stressed participants, 17.3%, 49.1%, 24.8% and 8.7% of participants suffered from mild, moderate, severe and extremely severe stress, respectively. Stressed participants were more preferred to eat junk foods such as fast foods, snacks and beverages as compared with unstressed participants (p < 0.05) and the junk food preference was increased with the increase of stress levels. Moreover, non-stressed participants preferred more healthy foods such as vegetarian food, fresh fruits as compared with stressed participants (p < 0.05). Taste and easy to access were the main reasons for the preference of junk foods by the stressed participants. CONCLUSIONS: This is the first comprehensive study from Saudi Arabia to show stress associated dietary alterations in undergraduates of Qassim University. Data concluded that most of the young adults followed a healthy eating pattern, but a significant number from them were affected by stress. Therefore, specific intervention programs are strongly recommended for the reduction of stress and to improve their quality of life.

MicroRNA-125b-5p regulates IL-1ß induced inflammatory genes via targeting TRAF6-mediated MAPKs and NF-κB signaling in human osteoarthritic chondrocytes.

Abnormal post-transcriptional modulations in inflammatory genes by microRNAs (miRNAs) play a crucial role in human disorders including arthritis. In this study, we determined the effect of hsa-miR-125b-5p on interleukin (IL)-1ß induced inflammatory genes in human osteoarthritic (OA) chondrocytes. Bioinformatics algorithms showed 3'untranslated region (3'UTR) of TRAF6 mRNA (NM_004620.3) has perfectly matched 'seed-sequence' for hsa-miR-125b-5p. Treatment of cells with IL-1ß up-regulates TRAF6 mRNA and down-regulates hsa-miR-125b-5p expression. This negative correlation between TRAF6 and hsa-miR-125b-5p was verified by transfection with miR-125b mimic (pre-miR-125b). Moreover, transfection with miR-125b mimic caused marked inhibition of IL-1ß-induced phosphorylation of p38-MAPK, JNK-MAPKs and ERK-MAPKs and also suppressed the nuclear levels of NF-κBp50, NF-κBp65 and inhibited the activation of IκBα. Furthermore, transfected chondrocytes with miR-125b mimic in the presence of IL-1ß also showed marked inhibition in the secretion of several proinflammatory cytokines, chemokines and growth factors including IL-6, IL-8, INF-γ, TGF-ß1, IGFBP-1 and PGDF-BB. Importantly, this transfection also significantly inhibited IL-1ß- induced MMP-13 expression/production. In short, this study concludes that hsa-miR-125b-5p acts as a negative co-regulator of inflammatory genes including MMP-13 via targeting TRAF6/MAPKs/NF-κB pathway in human OA chondrocytes.

Elevated Levels of Protein Carbonylation in Patients With Diabetic Nephropathy: Therapeutic and Diagnostic Prospects.

BACKGROUND: Oxidative stress-induced protein oxidation has been reported in diabetes mellitus; however a relationship between protein carbonylation and diabetic nephropathy remains to be determined. This study was undertaken to investigate a correlation between protein carbonylation and diabetic nephropathy. METHODS: Sera from 153 patients with diabetic nephropathy and 142 healthy humans were selected and protein carbonylation was compared. The glycated hemoglobin (HbA1C), postprandial blood glucose (PPBG), disease duration (DD) and serum creatinine were analyzed and were correlated with the levels of protein oxidation. RESULTS: Protein carbonylation was more pronounced in patients with diabetic nephropathy as compared with healthy humans (P < 0.001). The data showed a positive correlation between protein oxidation and HbA1C (P < 0.001, r = 0.752); the carbonylation was high in those patients with high HbA1C (P < 0.01). The data also showed an important correlation between protein oxidation and PPBG (P < 0.0001, r = 0.680); the carbonyl contents were higher in those patients with higher PPBG (P < 0.001). Results also pointed out a positive correlation of protein oxidation with patients DD (P < 0.001, r = 0.769). Importantly, elevated levels of carbonylation in patients with diabetic nephropathy were also correlated with the elevated levels of serum creatinine. CONCLUSIONS: This is the first study that shows a positive correlation between protein carbonylation and diabetic nephropathy. The higher carbonylation in patients with higher HbA1C, blood glucose, DD or serum creatinine indicate that oxidative modifications in proteins play a key role in the progression of diabetic nephropathy.

Epigallocatechin-3-O-gallate modulates global microRNA expression in interleukin-1ß-stimulated human osteoarthritis chondrocytes: potential role of EGCG on negative co-regulation of microRNA-140-3p and ADAMTS5.

PURPOSE: MicroRNAs (miRNAs) are short, non-coding RNAs involved in almost all cellular processes. Epigallocatechin-3-O-gallate (EGCG) is a green tea polyphenol and is known to exert anti-arthritic effects by inhibiting genes associated with osteoarthritis (OA). This study was undertaken to investigate the global effect of EGCG on interleukin-1ß (IL-1ß)-induced expression of miRNAs in human chondrocytes. METHODS: Human chondrocytes were derived from OA cartilage and then treated with EGCG and IL-1ß. Human miRNA microarray technology was used to determine the expression profile of 1347 miRNAs. Microarray results were verified by taqman assays and transfection of chondrocytes with miRNA inhibitors. RESULTS: Out of 1347 miRNAs, EGCG up-regulated expression of 19 miRNAs and down-regulated expression of 17 miRNAs, whereas expression of 1311 miRNAs remains unchanged in IL-1ß-stimulated human OA chondrocytes. Bioinformatics approach showed that 3`UTR of ADAMTS5 mRNA contains the 'seed-matched-sequence' for hsa-miR-140-3p. IL-1ß-induced expression of ADAMTS5 correlated with down-regulation of hsa-miR-140-3p. Importantly, EGCG inhibited IL-1ß-induced ADAMTS5 expression and up-regulated the expression of hsa-miR-140-3p. This EGCG-induced co-regulation between ADAMTS5 and hsa-miR-140-3p becomes reversed in OA chondrocytes transfected with anti-miR-140-3p. CONCLUSIONS: This study provides an important insight into the molecular basis of the reported anti-arthritic effects of EGCG. Our data indicate that the potential of EGCG in OA chondrocytes may be related to its ability to globally inhibit inflammatory response via modulation of miRNAs expressions.

Protein Mediated Oxidative Stress in Patients with Diabetes and its Associated Neuropathy: Correlation with Protein Carbonylation and Disease Activity Markers.

INTRODUCTION: Free radicals have been implicated as Diabetes Mellitus (DM) contributors in type 2 DM and its associated Diabetes Mellitus Neuropathy (DMN). However, the potential for protein mediated oxidative stress to contribute disease pathogenesis remains largely unexplored. AIM: To investigate the status and contribution of protein mediated oxidative stress in patients with DM or DMN and to explore whether oxidative protein modification has a role in DM progression to DM associated neuropathy. MATERIALS AND METHODS: Sera from 42 DM and 37 DMN patients with varying levels of disease activities biomarkers (HbA1C, patients' age or disease duration) and 21 age- and sex-matched healthy controls were evaluated for serum levels of protein mediated oxidative stress. RESULTS: Serum analysis showed significantly higher levels of protein carbonyl contents in both DM and DMN patients compared with healthy controls. Importantly, not only was there an increased number of subjects positive for protein carbonylation, but also the levels of protein carbonyl contents were significantly higher among DM and DMN patients, whose HbA1C were ≥8.8 as compared with patients with lower HbA1C (HbA1C<8.8). Similar pattern of protein carbonyls formation was also observed with patients' ages or with patient's disease durations, suggesting a possible relationship between protein oxidation and disease progression. Furthermore, sera from DMN patients had higher levels of protein carbonylation compared with non-neuropathic DM patients' sera, suggesting an involvement of protein oxidation in the progression of diabetes to diabetes neuropathy. CONCLUSION: These findings support an association between protein oxidation and DM or DMN progression. The stronger response observed in patients with higher HbA1C or patients' ages or disease durations suggests, that protein mediated oxidative stress may be useful in evaluating the progression of DM and its associated DMN and in elucidating the mechanisms of these disorders pathogenesis.

Epigallocatechin-3-O-gallate up-regulates microRNA-199a-3p expression by down-regulating the expression of cyclooxygenase-2 in stimulated human osteoarthritis chondrocytes.

Osteoarthritis (OA) is a most common form of arthritis worldwide leading to significant disability. MicroRNAs (miRNAs) are non-coding RNAs involved in various aspects of cartilage development, homoeostasis and pathology. Several miRNAs have been identified which have shown to regulate expression of target genes relevant to OA pathogenesis such as matrix metalloproteinase (MMP)-13, cyclooxygenase (COX)-2, etc. Epigallocatechin-3-O-gallate (EGCG), the most abundant and active polyphenol in green tea, has been reported to have anti-arthritic effects, however, the role of EGCG in the regulation of miRNAs has not been investigated in OA. Here, we showed that EGCG inhibits COX-2 mRNA/protein expression or prostaglandin E2 (PGE2 ) production via up-regulating microRNA hsa-miR-199a-3p expression in interleukin (IL)-1ß-stimulated human OA chondrocytes. This negative co-regulation of hsa-miR-199a-3p and COX-2 by EGCG was confirmed by transfection of OA chondrocytes with anti-miR-199a-3p. Transfection of OA chondrocytes with anti-miR-199a-3p significantly enhanced COX-2 expression and PGE2 production (P < 0.001), while EGCG treatment significantly inhibited anti-miR-199a-3p transfection-induced COX-2 expression or PGE2 production in a dose-dependent manner. These results were further re-validated by co-treatment of these transfection OA chondrocytes with IL-1ß and EGCG. EGCG treatment consistently up-regulated the IL-1ß-decreased hsa-miR-199a-3p expression (P < 0.05) and significantly inhibited the IL-1ß-induced COX-2 expression/PGE2 production (P < 0.05) in OA chondrocytes transfected with anti-hsa-miR-199a-3p. Taken together, these results clearly indicate that EGCG inhibits COX-2 expression/PGE2 production via up-regulation of hsa-miR-199a-3p expression. These novel pharmacological actions of EGCG on IL-1ß-stimulated human OA chondrocytes provide new suggestions that EGCG or EGCG-derived compounds inhibit cartilage breakdown or pain by up-regulating the expression of microRNAs in human chondrocytes.

Integrated Study of Globally Expressed microRNAs in IL-1ß-stimulated Human Osteoarthritis Chondrocytes and Osteoarthritis Relevant Genes: A Microarray and Bioinformatics Analysis.

This study was undertaken to identify and characterize the globally expressed microRNAs (miRNAs) involved in interleukin-1ß (IL-1ß)-induced joint damage and to predict whether miRNAs can regulate the catabolic effects in osteoarthritis (OA) chondrocytes. Out of 1347 miRNAs analyzed by microarrays in IL-1ß-stimulated OA chondrocytes, 35 miRNAs were down-regulated, 1 miRNA was up-regulated, and the expression of 1311 miRNAs remained unchanged. Bioinformatics analysis showed the key inflammatory mediators and key molecular pathways are targeted by differentially expressed miRNAs. Novel miRNAs identified could have important diagnostic and therapeutic potentials in the development of novel therapeutic strategies for pain managements in OA.

Lactoferrin from Camelus dromedarius Inhibits Nuclear Transcription Factor-kappa B Activation, Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Stimulated Human Chondrocytes.

BACKGROUND: Osteoarthritis (OA) is a progressive joint disorder, which remains the leading cause of chronic disability in aged people. Nuclear factor-kappa B (NF)-κB is a major cellular event in OA and its activation by interleukin-1ß (IL-1ß) plays a critical role in cartilage breakdown in these patients. OBJECTIVE: In this study, we examined the effect of lactoferrin on NF-κB activation, cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) production in stimulated human articular chondrocytes. MATERIALS AND METHODS: Human chondrocytes were derived from OA articular cartilage and treated with camel lactoferrin and then stimulated with IL-1ß. Gene expression was determined by TaqMan assays and protein expression was studied by Western immunoblotting. NF-κB activity and PGE2 levels were determined by ELISA based assays. NF-κB activity was also determined by treatment of chondrocytes with NF-κB specific inhibitor Bay 11-7082. RESULTS: Lactoferrin inhibited IL-1ß-induced activation and nuclear translocation of NF-κB p65 in human OA chondrocytes. Lactoferrin also inhibited mRNA/protein expression of COX-2 and production of PGE2. Moreover, Bay 11-7082 also inhibited IL-1ß-induced expression of COX-2 and production of PGE2. The inhibitory effect of lactoferrin on the IL-1ß induced expression of COX-2 or production of PGE2 was mediated at least in part via suppression of NF-κB activation. CONCLUSIONS: Our data determine camel lactoferrin as a novel inhibitor of IL-1ß-induced activation of NF-κB signaling events and production of cartilage-degrading molecule PGE2 via inhibition of COX-2 expressions. These results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA and other degenerative/inflammatory diseases. SUMMARY: Lactoferrin shows anti-arthritic activity in IL-1ß stimulated primary human chondrocytes.Lactoferrin inhibits IL-1ß-induced NF-κB activation.Lactoferrin inhibits production of cartilage degrading PGE2 via inhibition of COX-2 expression. Abbreviations Used: OA: Osteoarthritis IL-1ß: Interleukin-1 beta NF-κB: Nuclear factor-kappa B COX-2: cyclooxygenase-2 PGE2: prostaglandin E2.