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Glucocorticoids (GCs) are widely used as powerful anti-inflammatory and immunosuppressive therapeutics in multiple pathological conditions. However, compelling evidence indicates that they might promote neurodegeneration by altering mitochondrial homeostatic processes. Although the effect of dexamethasone on cell survival and homeostasis has been widely investigated, the effect of other glucocorticoids needs to be explored in more detail. In this report, we have compared the neurotoxicity induced by dexamethasone, prednisolone, betamethasone, and hydrocortisone in cultured neuroblastoma cells, through the analysis of several parameters such as cell viability, ER stress, oxidative stress, and mitochondrial fusion and fission markers. Interestingly, we have found that synthetic glucocorticoids may impact neuronal viability by affecting different cellular responses, suggesting that their therapeutic use should be consciously decided after careful consideration of benefits and detrimental effects.
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Supervivencia Celular , Glucocorticoides , Neuroblastoma , Estrés Oxidativo , Glucocorticoides/farmacología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Neuroblastoma/patología , Línea Celular Tumoral , Humanos , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estrés del Retículo Endoplásmico/fisiología , Dexametasona/farmacología , Hidrocortisona/farmacología , Prednisolona/farmacología , Betametasona/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismoRESUMEN
Progressive cartilage deterioration leads to chronic inflammation and loss of joint function, causing osteoarthritis (OA) and joint disease. Although symptoms vary among individuals, the disease can cause severe pain and permanent disability, and effective therapies are urgently needed. Human Adipose-Derived Stem Cells (ADSCs) may differentiate into chondrocytes and are promising for treating OA. Moreover, recent studies indicate that electromagnetic fields (EMFs) could positively affect the chondrogenic differentiation potential of ADSCs. In this work, we investigated the impact of EMFs with frequencies of 35 Hertz and 58 Hertz, referred to as extremely low frequency-EMFs (ELF-EMFs), on the chondrogenesis of ADSCs, cultured in both monolayer and 3D cell micromasses. ADSC cultures were daily stimulated for 36 min with ELF-EMFs or left unstimulated, and the progression of the differentiation process was evaluated by morphological analysis, extracellular matrix deposition, and gene expression profiling of chondrogenic markers. In both culturing conditions, stimulation with ELF-EMFs did not compromise cell viability but accelerated chondrogenesis by enhancing the secretion and deposition of extracellular matrix components at earlier time points in comparison to unstimulated cells. This study showed that, in an appropriate chondrogenic microenvironment, ELF-EMFs enhance chondrogenic differentiation and may be an important tool for supporting and accelerating the treatment of OA through autologous adipose stem cell therapy.
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Tejido Adiposo , Diferenciación Celular , Condrogénesis , Campos Electromagnéticos , Células Madre Mesenquimatosas , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Tejido Adiposo/citología , Células Cultivadas , Condrocitos/citología , Condrocitos/metabolismo , Matriz Extracelular/metabolismo , Supervivencia Celular/efectos de la radiaciónRESUMEN
(1) Background: Dry eye disease (DED) is a multifactorial ocular surface disease characterized by an imbalance in ocular surface homeostasis, and tear substitutes constitute the first line of treatment. The present study aimed to evaluate the changes in the signs and symptoms of patients with DED treated with a novel tear substitute containing the GlicoPro® complex. (2) Methods: Patients with DED not successfully responding to other tear substitutes were enrolled and treated with a novel ophthalmic solution (two drops four times daily). Patients were examined before starting the study treatment (T0) and after 30 (T1) and 60 (T2) days of treatment by means of Keratograph for the evaluation of the following: (i) tear meniscus height (TMH); (ii) noninvasive Keratograph break-up time (NIKBUT); (iii) bulbar redness; and (iv) infrared meibography. The SANDE questionnaire was administered to assess ocular discomfort symptoms. Analysis of the tear content of proenkephalin and Met/Leu-enkephalin was also performed. (3) Results: At T2, a significant improvement in NIKBUT first, average, and class, TMH, and SANDE score was found. The tear content of proenkephalins was significantly higher at T1, whereas processed active Met/Leu-enkephalins increased at both T1 and T2. (4) Conclusions: Our novel tear substitute based on GlicoPro® resulted in a significant improvement in ocular discomfort symptoms, tear volume, and stability in the patients treated. The increase in active peptides processed in tears may represent the pathophysiological substrate underlying this finding.
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Combining exercise with fasting is known to boost fat mass-loss, but detailed analysis on the consequential mobilization of visceral and subcutaneous WAT-derived fatty acids has not been performed. In this study, a subset of fasted male rats (66 h) was submitted to daily bouts of mild exercise. Subsequently, by using gas chromatography-flame ionization detection, the content of 22 fatty acids (FA) in visceral (v) versus subcutaneous (sc) white adipose tissue (WAT) depots was compared to those found in response to the separate events. Findings were related to those obtained in serum and liver samples, the latter taking up FA to increase gluconeogenesis and ketogenesis. Each separate intervention reduced scWAT FA content, associated with increased levels of adipose triglyceride lipase (ATGL) protein despite unaltered AMP-activated protein kinase (AMPK) Thr172 phosphorylation, known to induce ATGL expression. The mobility of FAs from vWAT during fasting was absent with the exception of the MUFA 16:1 n-7 and only induced by combining fasting with exercise which was accompanied with reduced hormone sensitive lipase (HSL) Ser563 and increased Ser565 phosphorylation, whereas ATGL protein levels were elevated during fasting in association with the persistently increased phosphorylation of AMPK at Thr172 both during fasting and in response to the combined intervention. As expected, liver FA content increased during fasting, and was not further affected by exercise, despite additional FA release from vWAT in this condition, underlining increased hepatic FA metabolism. Both fasting and its combination with exercise showed preferential hepatic metabolism of the prominent saturated FAs C:16 and C:18 compared to the unsaturated FAs 18:1 n-9 and 18:2 n-6:1. In conclusion, depot-specific differences in WAT fatty acid molecule release during fasting, irrelevant to their degree of saturation or chain length, are mitigated when combined with exercise, to provide fuel to surrounding organs such as the liver which is correlated with increased ATGL/ HSL ratios, involving AMPK only in vWAT.
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Ácidos Grasos , Esterol Esterasa , Ratas , Masculino , Animales , Esterol Esterasa/metabolismo , Ácidos Grasos/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Lipasa/metabolismo , Lipólisis/fisiología , Obesidad/metabolismo , Ayuno/metabolismo , Tejido Adiposo/metabolismoRESUMEN
This study evaluated the effects of supplementing with natural functional feed on the plasma fatty acid profile of lactating Italian Holstein-Friesian dairy cows. Thirty cows in mid-lactation received the natural olive extract PHENOFEED DRY (500 mg/cow/day) which mainly comprises hydroxytyrosol, tyrosol and verbascoside. The total content of polyphenols and the antioxidant power of standard feed, enriched feed and pure extract was evaluated respectively by Folin-Ciocalteu and DPPH assay, and a characterization in HPLC-UV (High-Performance Liquid Chromatography-Ultraviolet) of bioactive molecules present in the extract PHENOFEED DRY was performed. PHENOFEED DRY was provided for 60 days, and the plasma profile of fatty acids was determined by Gas Chromatography. The administration of enriched feed resulted in an increase in the ratio of Omega-6 to Omega-3 polyunsaturated fatty acids from 3:1 to 4:1 (p<0.001). This was not influenced by the calving order. The addition of polyphenols helped to keep monounsaturated (MUFA) and saturated (SFA) levels constant and results in a significant increase in polyunsaturated (PUFA) fatty acid after 15 days of administration. The Omega-6/Omega-3 ratio was in the optimal range. The findings show that inclusion of natural functional food such as plant polyphenols helps to maintain a healthy blood fatty acid profile in lactating dairy cows.
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Long-lived individuals (LLIs) are considered an ideal model to study healthy human aging. Blood fatty acid (FA) profile of a cohort of LLIs (90-111 years old, n = 49) from Sicily was compared to adults (18-64 years old, n = 69) and older adults (65-89 years old, n = 54) from the same area. Genetic variants in key enzymes related to FA biosynthesis and metabolism were also genotyped to investigate a potential genetic predisposition in determining the FA profile. Gas chromatography was employed to determine the FA profile, and genotyping was performed using high-resolution melt (HRM) analysis. Blood levels of total polyunsaturated FA (PUFA) and total trans-FA decreased with age, while the levels of saturated FA (SFA) remained unchanged. Interestingly, distinctively higher circulatory levels of monounsaturated FA (MUFA) in LLIs compared to adults and older adults were observed. In addition, among LLIs, rs174537 in the FA desaturase 1/2 (FADS1/2) gene was associated with linoleic acid (LA, 18:2n-6) and docosatetraenoic acid (DTA, 22:4n-6) levels, and the rs953413 in the elongase of very long FA 2 (ELOVL2) was associated with DTA levels. We further observed that rs174579 and rs174626 genotypes in FADS1/2 significantly affect delta-6 desaturase (D6D) activity. In conclusion, our results suggest that the LLIs have a different FA profile characterized by high MUFA content, which indicates reduced peroxidation while maintaining membrane fluidity.
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Ácidos Grasos Monoinsaturados , Ácidos Grasos , Humanos , Anciano , Anciano de 80 o más Años , Ácidos Grasos Monoinsaturados/análisis , Ácidos Grasos Monoinsaturados/metabolismoRESUMEN
In the COVID-19 pandemic year 2021, several countries have implemented a vaccine certificate policy, the "Green Pass Policy" (GPP), to reduce virus spread and to allow safe relaxation of COVID-19 restrictions and reopening of social and economic activities. The rationale for the GPP is based on the assumption that vaccinated people should maintain a certain degree of immunity to SARS-CoV-2. Here we describe and compare, for the first time, the humoral immune response to mRNA-1273, BNT162b2, Ad26.COV2.S, and ChAdOx1 nCoV-19 vaccines in terms of antibody titer elicited, neutralizing activity, and epitope reactogenicity among 369 individuals aged 19 to 94 years. In parallel, we also considered the use of a rapid test for the determination of neutralizing antibodies as a tool to guide policymakers in defining booster vaccination strategies and eligibility for Green Pass. Our analysis demonstrates that the titer of antibodies directed towards the receptor-binding domain (RBD) of SARS-CoV-2 Spike is significantly associated with age and vaccine type. Moreover, natural COVID-19 infection combined with vaccination results, on average, in higher antibody titer and higher neutralizing activity as compared to fully vaccinated individuals without prior COVID-19. We also found that levels of anti-Spike RBD antibodies are not always strictly associated with the extent of inhibition of RBD-ACE2 binding, as we could observe different neutralizing activities in sera with similar anti-RBD concentrations. Finally, we evaluated the reactivity to four synthetic peptides derived from Spike protein on a randomly selected serum sample and observed that similar to SARS-CoV-2 infection, vaccination elicits a heterogeneous antibody response with qualitative individual features. On the basis of our results, the use of rapid devices to detect the presence of neutralizing antibodies, even on a large scale and repeatedly over time, appears helpful in determining the duration of the humoral protection elicited by vaccination. These aspects and their implications for the GPP are discussed.
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COVID-19 , Vacunas Virales , Ad26COVS1 , Animales , Anticuerpos Neutralizantes , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19 , ChAdOx1 nCoV-19 , Humanos , Inmunidad Humoral , Ratones , Ratones Endogámicos BALB C , Pandemias , Políticas , SARS-CoV-2RESUMEN
Molecular tests are the gold standard to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but are associated with a diagnostic delay, while antigen detection tests can generate results within 20 min even outside a laboratory. In order to evaluate the accuracy and reliability of the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit (Ag-RDT), two respiratory swabs were collected simultaneously from 501 patients, with mild or no coronavirus disease 2019 (COVID-19)-related symptoms, and analyzed with both the Reverse Transcriptase-quantitative Polymerase Chain Reaction (RT-qPCR) and the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test. Results were then compared to determine clinical performance in a screening setting. We measured a precision of 97.41% (95% CI 92.42-99.15%) and a recall of 98.26% (95% CI 93.88-99.25%), with a specificity of 99.22% (95% CI 97.74-99.74%), a negative predictive value of 99.48% (95% CI 97.98-99.87%), and an overall accuracy of 99.00% (95% CI 97.69-99.68%). Concordance was described by a Kappa coefficient of 0.971 (95% CI 0.947-0.996). Considering short lead times, low cost, and opportunities for decentralized testing, the Ag-RDT test can enhance the efforts to control SARS-CoV-2 spread in several settings.
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The use of medical devices, such as contact lenses, represents a substantial risk of infection, as they can act as scaffolds for formation of microbial biofilms. Recently, the increasing emergency of antibiotic resistance has prompted the development of novel and effective antimicrobial drugs for biofilm treatment, such as oxidizing agents. The purpose of this study is to investigate the effects of Ozodrop® and Ozodrop® gel, commercial names of ozonated oil in liposomes plus hypromellose, on eradication and de novo formation of biofilms on different supports, such as plastic plates and contact lens. Our results demonstrate that ozonated liposomal sunflower oil plus hypromellose have an excellent inhibitory effect on bacterial viability and on both de novo formation and eradication of biofilms produced on plates and contact lens by Pseudomonas aeruginosa and Staphylococcus aureus. Moreover, we show that Ozodrop® formulations stimulate expression of antimicrobial peptides and that Ozodrop® gel has a strong repair activity on human epithelial cells, suggesting further applications for the treatment of non-healing infected wounds.
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Liposomas , Pseudomonas aeruginosa , Antibacterianos/farmacología , Biopelículas , Humanos , Derivados de la Hipromelosa/farmacología , Liposomas/farmacología , Pruebas de Sensibilidad Microbiana , Staphylococcus aureusRESUMEN
SARS-CoV-2 virus is responsible for the current worldwide coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing hundreds of thousands of deaths. Understanding the antibody response to SARS-CoV-2 is crucial for the development of vaccines, therapeutics and public health interventions. However, lack of consistency in methods used to monitor antibody response to SARS-CoV-2 leaves some uncertainty in our fine understanding of the human antibody response mounted following SARS-CoV-2 infection. We developed a peptide-based enzyme-linked immunosorbent assay (ELISA) by selecting 7 synthetic peptides from the spike, membrane, and nucleocapsid protein sequences of SARS-CoV-2, which effectively detects the antibody response mounted by all COVID-19 convalescent tested. Strikingly, the assay shows a profound difference in antibody response among individual subjects, which may have a significant impact on disease severity. Together, our results define an efficient and specific serological assay to consistently measure the antibody response following SARS-CoV-2 infection, as well as help the design of vaccine and therapeuticals for prevention and treatment of COVID-19.
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The coronavirus disease 2019 (COVID-19) mRNA vaccine developed by Pfizer/BioNTech has been shown to be capable of developing an excellent antibody response against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, with good production of neutralizing antibodies. Herein, we analyzed differences in the antibody response elicited by inoculation of the Pfizer/BioNTech vaccine through a peptide-based enzyme-linked immunosorbent assay (ELISA) that utilizes synthetic peptides derived from the spike protein in the immuno-adsorbent phase. Immunoreactivity against synthetic peptides was measured at different time points from vaccination and was also correlated with the SARS-CoV-2 neutralizing capacity. Our results indicate that all vaccinated subjects except one show reactive antibodies to at least one peptide at both 30 and 60 days after injection of the first dose. Only one of the 19 analyzed subjects showed no antibody response toward any of the selected peptides, consistently with a lower neutralizing capacity. More importantly, our data showed that the antibody response elicited by inoculation of the two doses of the Pfizer vaccine appears to be qualitatively individual, both in the type of recognized peptides and in the temporal persistence of the antibody response. Together with previous published data, our findings suggest that for effective pandemic control, it is important to constantly monitor the antibody protection in the population, and the assay described here could be a valid tool for this purpose.
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Since the beginning of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, it has been clear that testing large groups of the population was the key to stem infection and prevent the effects of the coronavirus disease of 2019, mostly among sensitive patients. On the other hand, time and cost-sustainability of virus detection by molecular analysis such as reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) may be a major issue if testing is extended to large communities, mainly asymptomatic large communities. In this context, sample-pooling and test grouping could offer an effective solution. Here we report the screening on 1195 oral-nasopharyngeal swabs collected from students and staff of the Università degli Studi del Sannio (University of Sannio, Benevento, Campania, Italy) and analyzed by an in-house developed multiplex RT-qPCR for SARS-CoV-2 detection through a simple monodimensional sample pooling strategy. Overall, 400 distinct pools were generated and, within 24 h after swab collection, five positive samples were identified. Out of them, four were confirmed by using a commercially available kit suitable for in vitro diagnostic use (IVD). High accuracy, sensitivity and specificity were also determined by comparing our results with a reference IVD assay for all deconvoluted samples. Overall, we conducted 463 analyses instead of 1195, reducing testing resources by more than 60% without lengthening diagnosis time and without significant losses in sensitivity, suggesting that our strategy was successful in recognizing positive cases in a community of asymptomatic individuals with minor requirements of reagents and time when compared to normal testing procedures.
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SARS-CoV-2 is a zoonotic betacoronavirus associated with worldwide transmission of COVID-19 disease. By the beginning of March, WHO reported about 113,820,000 confirmed cases including more than 2,527,000 deaths all over the world. However, the true extent of virus circulation or its real infection/fatality ratio is not well-estimated due to the huge portion of asymptomatic infections. In this observational study, we have estimated the prevalence of specific immunoglobulin M and G directed towards SARS-CoV-2 antigen in a cohort of 1383 adult volunteers aged over 65 years old, living in the district of Benevento, in the South of Italy. Serological screening was carried out on capillary blood in September 2020, seven months after pandemic outbreak in Italy, to evaluate virus circulation and antibody response among elderly adults, in which severe symptoms due to viral infection are more common. The overall seroprevalence of anti-SARS-CoV-2 antibodies was 4.70% (CI 3.70%-5.95%) with no statistically significant differences between sexes. Among these, 69.69% (CI 55.61%-77.80%) tested positive to IgM, 23.08% (CI 14.51%-34.64%) to IgG and 9.23% (CI 4.30%-18.71%) was positive for both. All patients that were positive to IgM underwent molecular testing through RT-qPCR on oral-rhino pharyngeal swabs and only one specimen was positive for SARS-CoV-2 RNA detection. Instead, the presence of IgG from screened volunteers was confirmed by re-testing serum samples using both an ELISA assay validated for in vitro diagnostic use (IVD) and a recently published synthetic peptide-based ELISA assay. In conclusion, our report suggests that (1) early restrictions were successful in limiting COVID-19 diffusion in the district of Benevento; (2) rapid serological analysis is an ideal testing for both determining real seroprevalence and massive screening, whereas detection of viral RNA remains a gold standard for identification of infected patients; (3) even among people without COVID-19 related symptoms, the antibody response against SARS-CoV-2 antigens has individual features.
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CARD14/CARMA2 is a scaffold molecule whose genetic alterations are linked to human inherited inflammatory skin disorders. However, the mechanisms through which CARD14/CARMA2 controls innate immune response and chronic inflammation are not well understood. By means of a yeast two-hybrid screening, we identified the UBA Domain Containing 1 (UBAC1), the non-catalytic subunit of the E3 ubiquitin-protein ligase KPC complex, as an interactor of CARMA2sh, the CARD14/CARMA2 isoform mainly expressed in human keratinocytes. UBAC1 participates in the CARMA2sh/TANK complex and promotes K63-linked ubiquitination of TANK. In human keratinocytes, UBAC1 negatively regulates the NF-κF-activating capacity of CARMA2sh following exposure to poly (I:C), an agonist of Toll-like Receptor 3. Overall, our data indicate that UBAC1 participates in the inflammatory signal transduction pathways involving CARMA2sh.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras de Señalización CARD/metabolismo , Guanilato Ciclasa/metabolismo , Proteínas de la Membrana/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Células HEK293 , Células HaCaT , Humanos , FN-kappa B/metabolismo , Unión Proteica , Transducción de Señal , Receptor Toll-Like 3/metabolismo , UbiquitinaciónRESUMEN
Purpose: To determine the levels of pro-inflammatory cytokines and soluble mediators (TNF-α, IL6, IL2, and PDGF-AB) in 28 vitreous biopsies taken from patients with proliferative diabetic retinopathy (PDR) and treated with increasing doses of curcumin (0. 5 and 1 µM), with or without homotaurine (100 µM) and vitamin D3 (50 nM). Materials and Methods: ELISA tests were performed on the supernatants from 28 vitreous biopsies that were incubated with bioactive molecules at 37°C for 20 h. The concentration of the soluble mediators was calculated from a calibration curve and expressed in pg/mL. Shapiro-Wilk test was used to verify the normality of distribution of the residuals. Continuous variables among groups were compared using the General Linear Model (GLM). Homoscedasticity was verified using Levene and Brown-Forsythe tests. Post-hoc analysis was also performed with the Tukey test. A p ≤ 0.05 was considered statistically significant. Results: The post-hoc analysis revealed statistically detectable changes in the concentrations of TNF-α, IL2, and PDGF-AB in response to the treatment with curcumin, homotaurine, and vitamin D3. Specifically, the p-values for between group comparisons are as follows: TNF-α: (untreated vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.008, (curcumin 0.5 µM vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.0004, (curcumin 0.5 µM vs. curcumin 1 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.02, (curcumin 1 µM vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.025, and (homotaurine 100 µM + vitamin D3 50 nM vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.009; IL2: (untreated vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.0023, and (curcumin 0.5 µM vs. curcumin 0.5 µM+ homotaurine 100 µM + vitamin D3 50 nM) p = 0.0028; PDGF-AB: (untreated vs. curcumin 0.5 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.04, (untreated vs. curcumin 1 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.0006, (curcumin 0.5 µM vs. curcumin 1 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.006, and (homotaurine 100 µM + vitamin D3 50 nM vs. curcumin 1 µM + homotaurine 100 µM + vitamin D3 50 nM) p = 0.022. IL6 levels were not significantly affected by any treatment. Conclusions: Pro-inflammatory cytokines are associated with inflammation and angiogenesis, although there is a discrete variability in the doses of the mediators investigated among the different vitreous samples. Curcumin, homotaurine, and vitamin D3 individually have a slightly appreciable anti-inflammatory effect. However, when used in combination, these substances are able to modify the average levels of the soluble mediators of inflammation and retinal damage. Multi-target treatment may provide a therapeutic strategy for diabetic retinopathy in the future. Clinical Trial Registration : The trial was registered at clinical trials.gov as NCT04378972 on 06 May 2020 ("retrospectively registered") https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid = S0009UI8&selectaction = Edit&uid = U0003RKC&ts = 2&cx = dstm4o.
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CARD14/CARMA2sh (CARMA2sh) is a scaffold protein whose mutations are associated with the onset of human genetic psoriasis and other inflammatory skin disorders. Here we show that the immunomodulatory adapter protein TRAF family member-associated NF-κB activator (TANK) forms a complex with CARMA2sh and MALT1 in a human keratinocytic cell line. We also show that CARMA2 and TANK are individually required to activate the nuclear factor κB (NF-κB) response following exposure to polyinosinic-polycytidylic (poly [I:C]), an agonist of toll-like receptor 3. Finally, we present data indicating that TANK is essential for activation of the TBK1/IRF3 pathway following poly (I:C) stimulation, whereas CARMA2sh functions as a repressor of it. More important, we report that two CARMA2sh mutants associated with psoriasis bind less efficiently to TANK and are therefore less effective in suppressing the TBK1/IRF3 pathway. Overall, our data indicate that TANK and CARMA2sh regulate TLR3 signaling in human keratinocytes, which could play a role in the pathophysiology of psoriasis.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras de Señalización CARD/metabolismo , Guanilato Ciclasa/metabolismo , Inflamación/metabolismo , Queratinocitos/metabolismo , Proteínas de la Membrana/metabolismo , Poli I-C/metabolismo , Proteínas Adaptadoras de Señalización CARD/genética , Línea Celular , Guanilato Ciclasa/genética , Células HEK293 , Humanos , Factor 3 Regulador del Interferón/metabolismo , Proteínas de la Membrana/genética , Mutación/genética , FN-kappa B/metabolismo , Unión Proteica/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Psoriasis/genética , Psoriasis/metabolismo , Transducción de Señal/fisiologíaRESUMEN
CARMA proteins represent a family of scaffold molecules which play several crucial biological functions, including regulation of immune response and inflammation, tissue homeostasis, and modulation of G-Protein Coupled Receptor (GPCR) signaling. Among the CARMA proteins, CARD14/CARMA2 and its alternatively spliced isoforms are specifically expressed in epithelial cells and keratinocytes. Recent evidences have shown that CARD14/CARMA2 mediates induction of inflammatory response in keratinocytes, and that mutations in CARD14/CARMA2 gene segregate with familial transmission of chronic inflammatory disorders of the human skin. Similarly to CARD11/CARMA1 and CARD10/CARMA3, CARD14/CARMA2 signaling occurs trough formation of a trimeric complex which includes BCL10 and MALT1 proteins. However, it is becoming increasingly evident that in addition to the CBM complex components, a number of accessory molecules are able to finely modulate the signals conveyed on and amplified by CARD14/CARMA2. The study of these molecules is important both to understand the molecular mechanisms that underlie the role of CARMA2 in keratinocytes and because they represent potential therapeutic targets for the development of therapeutic strategies aiming at the treatment of inflammatory diseases of the human skin. In this review, we provide an overview on the molecular mechanisms mediating CARD14/CARMA2 signaling and its implication in our understanding of the pathogenesis of human inflammatory skin disorders.
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Proteínas Adaptadoras de Señalización CARD/metabolismo , Dermatitis/inmunología , Guanilato Ciclasa/metabolismo , Proteínas de la Membrana/metabolismo , Transducción de Señal/inmunología , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/inmunología , Dermatitis/genética , Guanilato Ciclasa/genética , Guanilato Ciclasa/inmunología , Humanos , Queratinocitos/inmunología , Queratinocitos/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Piel/citología , Piel/inmunología , Piel/metabolismoRESUMEN
The nuclear factor (NF)-κB signaling pathway controls a variety of important biological functions, including immune and inflammatory responses, differentiation, cell growth, tumorigenesis, and apoptosis. Two distinct pathways of NF-κB activation are known. The classical, canonical pathway is found virtually in all mammalian cells and NF-κB activation is mediated by the IKK complex, consisting of the IKK1/IKKα and IKK2/IKKß catalytic kinase subunits and the NF-κB essential modulator (NEMO)/IKKγ protein. The NF-κB-driven transcriptional responses to many different stimuli have been widely characterized in the pathophysiology of the mammalian immune system, mainly because this transcription factor regulates the expression of cytokines, growth factors, and effector enzymes in response to ligation of cellular receptors involved in immunity and inflammation. However, an impressive literature produced in the last two decades shows that NF-κB signaling plays an important role also outside of the immune system, performing different roles and functions depending on the type of tissue and organ. In thyroid, NF-κB signaling is crucial for thyrocytes survival and expression of critical thyroid markers, including Nis, Ttf1, Pax8, Tpo, and thyroglobulin, making this transcription factor essential for maintenance of normal thyroid function.
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Regulación de la Expresión Génica/fisiología , FN-kappa B/metabolismo , Glándula Tiroides/fisiología , Animales , Humanos , Familia de Multigenes , FN-kappa B/genética , Unión Proteica , Conformación Proteica , Transducción de Señal/fisiologíaRESUMEN
The three CARD-containing MAGUK (CARMA) proteins function as scaffolding molecules that regulate activation of the pro-inflammatory transcription factor NF-κB. Recently, mutations in CARMA2 have been linked to psoriasis susceptibility due to their acquired altered capacity to activate NF-κB. By means of two-hybrid screening with yeast, we identified RING finger protein 7 (RNF7) as an interactor of CARMA2. We present evidence that RNF7 functions as a negative regulator of the NF-κB-activating capacity of CARMA2. Mechanistically, RNF7 influences CARMA2 signaling by regulating the ubiquitination state of MALT1 and the NF-κB-regulatory molecule NEMO. Interestingly, CARMA2short (CARMA2sh) mutants associated with psoriasis susceptibility escape the negative control exerted by RNF7. In conclusion, our findings identify a new mechanism through which the ability of CARMA2 to activate NF-κB is regulated, which could have significant implications for our understanding of why mutations of this protein trigger human psoriasis.
Asunto(s)
Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Guanilato Ciclasa/genética , Guanilato Ciclasa/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Adaptadoras de Señalización CARD/química , Línea Celular , Regulación de la Expresión Génica , Guanilato Ciclasa/química , Células HEK293 , Humanos , Quinasa I-kappa B/metabolismo , Proteínas de la Membrana/química , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas/metabolismo , Mutación , FN-kappa B/metabolismo , Unión Proteica , Ubiquitina-Proteína Ligasas/química , UbiquitinaciónRESUMEN
The molecular complexes formed by specific members of the family of CARMA proteins, the CARD domain-containing adapter molecule BCL10 and MALT1 (CBM complex) represent a central hub in regulating activation of the pleiotropic transcription factor NF-κB. Recently, missense mutations in CARMA2sh have been shown to cause psoriasis in a dominant manner and with high penetrancy. Here, we demonstrate that in human keratinocytes CARMA2sh plays an essential role in the signal transduction pathway that connects pathogen-associated molecular patterns recognition to NF-κB activation. We also find that the serine/threonine kinase ULK2 binds to and phosphorylates CARMA2sh, thereby inhibiting its capacity to activate NF-κB by promoting lysosomal degradation of BCL10, which is essential for CARMA2sh-mediated NF-κB signaling. Remarkably, CARMA2sh mutants associated with psoriasis escape ULK2 inhibition. Finally, we show that a peptide blocking CARD-mediated BCL10 interactions reduces the capacity of psoriasis-linked CARMA2sh mutants to activate NF-κB. Our work elucidates a fundamental signaling mechanism operating in human keratinocytes and opens to novel potential tools for the therapeutical treatment of human skin disorders.