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Teleost IgT/Z plays a principal role in the defense mechanisms against infectious agents in the mucosal compartments and in systemic immunity. Previously, Nile tilapia (Oreochromis niloticus) IgT was discovered and characterized at transcription level. In this work, we generated a monoclonal antibody (mAb) that specifically recognized the Nile tilapia IgT. BALB/c mice were immunized with three synthetic peptides conjugated to KLH. The sequences of these peptides derived from the constant region of the Nile tilapia IgT heavy chain. ELISA and Western blotting confirmed the specificity of the polyclonal sera and the culture supernatant from a positive hybridoma clone. We observed immunoreactivity against a recombinant IgT fragment and native IgT in skin mucus. The anti-IgT mAb did not cross-react with purified tilapia IgM. Direct ELISA analysis allowed the quantification of skin mucus IgM and IgT concentrations. Flow cytometry analysis revealed differences in the percentage of IgT+ B cell populations between juveniles and adults in peripheral blood, head kidney and spleen lymphocytes and among the tissues analyzed. For further validation of the anti-IgT mAb utility, a recombinant vaccine candidate against sea lice (TT-P0 Ls) was injected into juvenile tilapia. Direct ELISA results revealed a differential secretion of skin mucus IgT and IgM after immunostimulation. In addition, the percentages of IgT+ B cells were determined at 7 days after booster and ex-vivo stimulation by flow cytometry. This mAb constitutes an important immunological tool to study the biological function and structural characteristics of tilapia IgT.

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Chronic Non-Communicable Diseases (NCDs) have been considered a global health problem, characterized as diseases of multiple factors, which are developed throughout life, and regardless of genetics as a risk factor of important relevance, the increase in mortality attributed to the disease to environmental factors and the lifestyle one leads. Although the reactive species (ROS/RNS) are necessary for several physiological processes, their overproduction is directly related to the pathogenesis and aggravation of NCDs. In contrast, dietary polyphenols have been widely associated with minimizing oxidative stress and inflammation. In addition to their antioxidant power, polyphenols have also drawn attention for being able to modulate both gene expression and modify epigenetic alterations, suggesting an essential involvement in the prevention and/or development of some pathologies. Therefore, this review briefly explained the mechanisms in the development of some NCDs, followed by a summary of some evidence related to the interaction of polyphenols in oxidative stress, as well as the modulation of epigenetic mechanisms involved in the management of NCDs.

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Nile tilapia (Oreochromis niloticus) is a freshwater fish, which is extensively cultivated worldwide and constitutes one of the model species for the study of fish immunology. Monoclonal antibodies are very advantageous molecular tools for studying teleost immune system. Specifically, monoclonal antibodies that react with immunoglobulins are used successfully in the study of the humoral immune response of several fish species. In the present study, we produced and characterized a monoclonal antibody against tilapia IgM heavy chain using a peptide-based strategy. The peptide sequence was selected from the surface-exposed region between CH3-CH4 domains. The specificity of the polyclonal serum and the hybridoma culture supernatant obtained by immunization with the peptide conjugated to keyhole limpet hemocyanin were evaluated by western blotting, both showing reactivity against tilapia serum IgM. The purified mAb was able to recognize secreted IgM by western blotting and ELISA and membrane IgM by flow cytometry. We also demonstrated that the antibody doesn't cross-react with a recombinant IgT fragment. This tool allowed us to study for the first time the stimulation of mucosal immunity after Pituitary Adenylate Cyclase Activating Polypeptide administration. Overall, the results demonstrated the utility of this mAb to characterize humoral immune response in O. niloticus.

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Immunoglobulin molecules play an important role in the immune defense system in all jawed vertebrates, by protecting the organism from a wide variety of pathogens. Nile tilapia (Oreochromis niloticus) is extensively cultivated worldwide, with a strong established market demand. It constitutes one of the model species for the study of fish immunology and its genome is currently fully sequenced. The presence of the immunoglobulin M gene in this species is well documented, as well as its major role in systemic immunity. To date, the IgT gene from O. niloticus has not been identified and, therefore, no information is available on the role of this immunoglobulin isotype in the immune response in tilapia. In the present work, novel secreted and membrane immunoglobulin T isotypes and a fragment of IgM were isolated from tilapia head kidney lymphocytes. Their transcriptional profiles were analyzed by quantitative PCR in larval development and in different tissues of healthy or lipopolysaccharide/Edwardsiella tarda-challenged tilapia adults. The presence of IgT and IgM were detected in early stages of larval development. Additionally, these genes exhibited differential expression profiles in basal conditions and after E. tarda infection in adult tilapia, in accord with the proposed effector functions of these immunoglobulins in the systemic and mucosal compartments. Our results suggest the potential involvement of this new Ig in mucosal immunity in tilapia.

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BACKGROUND: Compare glycated hemoglobin (HbA1c ) diagnostic tests for prediabetes and diabetes with plasma glucose criteria and compare the metabolic profiles of people classified by HbA1c versus by glucose levels. METHODS: Participants were recruited for the San Juan Overweight Adults Longitudinal Study. The participants were primarily Hispanic (98%), without previously diagnosed diabetes, and aged 40 to 65 years. Participants classified as normal glycemic, prediabetes, or diabetes on the basis of baseline HbA1c and plasma glucose criteria were compared with respect to baseline cardiometabolic factors. RESULTS: The 1342 participants had a mean age of 50.5 ± 6.8 years and 28% were men. Thirty-one percent were diagnosed with prediabetes by plasma glucose criteria and 53.4% by HbA1c , and 8.1% were diagnosed with diabetes by plasma glucose criteria and 6.3% by HbA1c ; overall concordance rate was 55.1%. The area under the receiver operating characteristic curve of HbA1c compared to plasma glucose criteria was 0.62 for impaired glucose and 0.76 for diabetes. A worse cardiometabolic profile was seen within subgroups that met HbA1c and plasma glucose criteria for diabetes or prediabetes. Those diagnosed with prediabetes by plasma glucose criteria had significantly higher systolic blood pressure and higher homeostatic model assessment than those diagnosed using HbA1c . Participants diagnosed with diabetes by plasma glucose criteria had lower body mass index, smaller waist circumference, and lower insulinogenic and disposition indices, but higher homeostatic model assessment of insulin resistance, than those diagnosed by HbA1c . CONCLUSIONS: Low concordance was seen between HbA1c and glucose measurements. The HbA1c is not a good test for prediabetes but shows reasonable validity for diabetes in this high-risk predominantly female Hispanic population. People classified by HbA1c , plasma glucose criteria, or both show different metabolic profiles; a combined test may be ideal.

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AIM: This study evaluated the efficacy of oral magnesium supplementation in the reduction of plasma glucose levels in adults with prediabetes and hypomagnesaemia. METHODS: A total of 116 men and non-pregnant women, aged 30 to 65 years with hypomagnesaemia and newly diagnosed with prediabetes, were enrolled into a randomized double-blind placebo-controlled trial to receive either 30 mL of MgCl2 5% solution (equivalent to 382 mg of magnesium) or an inert placebo solution once daily for four months. The primary trial endpoint was the efficacy of magnesium supplementation in reducing plasma glucose levels. RESULTS: At baseline, there were no significant statistical differences in terms of anthropometric and biochemical variables between individuals in the supplement and placebo groups. At the end of follow-up, fasting (86.9 ± 7.9 and 98.3 ± 4.6 mg/dL, respectively; P = 0.004) and post-load glucose (124.7 ± 33.4 and 136.7 ± 23.9 mg/dL, respectively; P = 0.03) levels, HOMA-IR indices (2.85 ± 1.0 and 4.1 ± 2.7, respectively; P = 0.04) and triglycerides (166.4 ± 90.6 and 227.0 ± 89.7, respectively; P = 0.009) were significantly decreased, whereas HDL cholesterol (45.6 ± 10.9 and 46.8 ± 9.2 mg/dL, respectively; P = 0.04) and serum magnesium (1.96 ± 0.27 and 1.60 ± 0.26 mg/dL, respectively; P = 0.005) levels were significantly increased in those taking MgCl2 compared with the controls. A total of 34 (29.4%) people improved their glucose status (50.8% and 7.0% in the magnesium and placebo groups, respectively; P < 0.0005). CONCLUSION: Our results show that magnesium supplementation reduces plasma glucose levels, and improves the glycaemic status of adults with prediabetes and hypomagnesaemia.

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BACKGROUND: Because the role of 2-h postload glucose and insulin levels as confounders in the relationship between hypertriglyceridemia and development of metabolic glucose disorders (MGD) has not been elucidated, the aim of this study was to determine whether triglyceride levels ≥ 1.7 mmol/L are a risk factor of developing MGD in otherwise healthy men and women. METHODS: A total of 341 healthy men and non-pregnant women, 30 to 50 years of age, were enrolled in a 15-year follow-up study and allocated into the exposed (triglycerides ≥ 1.7 mmol/L) and non-exposed (triglycerides <1.7 mmol/L) groups. Follow-up visits were scheduled every 3 years to complete 5 visits (mean 3.8 visits). At final follow-up, about 15 years later (mean 13.6 years), contact was re-established in 236 individuals to complete 3540 person-years of follow-up. At baseline, all subjects in both groups were required to be free of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), IFG+IGT, and type 2 diabetes. RESULTS: The Poisson regression models, adjusted by age, sex, family history of diabetes, waist circumference, body mass index, total body fat, blood pressure, fasting and postload glucose, fasting and postload insulin, and HOMA-IR index, showed a significant association between triglycerides ≥ 1.7 mmol/L and IFG (relative risk - RR - 1.40; 95% CI 1.2-2.2), IGT (RR 1.60; 95% CI 1.3-2.2), IFG+IGT (RR 1.80; 95% CI 1.5-2.7), and type 2 diabetes (RR 3.0; 95% CI 2.5-3.8). CONCLUSIONS: Serum triglyceride levels ≥ 1.7 mmol/L are an independent risk factor of developing IFG, IGT, IFG+IGT, and type 2 diabetes in young and middle-aged, men and women.

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OBJECTIVE: To test the hypothesis that metabolic syndrome (MetS) is more predictive of carotid intima-media thickness (IMT) than the sum of the individual components of MetS. STUDY DESIGN: We analyzed the relationships between 2 definitions of the MetS and IMT in 461 overweight adolescents aged 10-18 years (median body mass index, 28.6 kg/m(2)). We used regression models and receiver operating characteristics (ROCs) for increased IMT (defined as ≥0.7 mm). RESULTS: The prevalence of MetS was 15.0% and 26.9% according to the 2 definitions applied. At the group level, quantitative IMT was associated with body mass index, blood pressure, glucose levels at 2 hours in an oral glucose tolerance test, and with each of the MetS components (all P < .05). At an individual level, using the MetS definitions alone as a diagnostic test for the presence of increased IMT (area under the ROC curve, 0.60-0.66) was inferior when compared with the sum of all individual components (area under the ROC curve, 0.65-0.85). Adding the presence or absence of MetS to the components did not improve the accuracy. CONCLUSION: Overweight adolescents with MetS demonstrated increased IMT values compared with overweight adolescents without MetS. The best model for diagnosing increased IMT was the sum of the quantitative components of MetS. The use of dichotomized variables reduced the diagnostic accuracy. Thus, in clinical practice, treatment of overweight adolescents should be based on weighing cardiovascular risk factors themselves, rather than on the dichotomous variable MetS.

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This study aimed at investigating differences in the performance of the young elderly and oldest old in tasks evaluating cognitive flexibility/inhibition (Stroop test), selective attention/working memory (Digit Span Subtest), premorbid intelligence/semantic knowledge (Vocabulary Subtest), and decision making (Iowa Gambling Task - IGT). Twenty healthy individuals were divided into two groups: 10 young elderly (M = 62 years, SD = 2.1) and 10 oldest old (M = 80 years, SD = 3.3), both with high educational level (M = 14 years of study, SD = 2.5). Results showed that the groups were only different in terms of decision making. There was also a difference in the learning process of each group; the young elderly reached more favorable scores in the IGT.