Growth hormone secretagogue peptide-6 enhances oreochromicins transcription and antimicrobial activity in tilapia (Oreochromis sp.).

Growth Hormone-Releasing Peptide 6 (GHRP-6) (His-(D-Trp)-Ala-Trp-(D-Phe)-Lys-NH2) is an agonist of the growth hormone secretagogue receptor. GHRP-6 mimics the effect of ghrelin. The present study focuses on the immunomodulatory effects of GHRP-6 in tilapia with and without the presence of Pseudomonas aeruginosa infection. GHRP-6 up-regulated the transcription levels of three piscidin-like antimicrobial peptides (Oreochromicins I, II, and III) and granzyme in a tissue-dependent manner. Antimicrobial activity stimulation in serum (lysozyme and anti-protease activity) was also confirmed. Besides, GHRP-6 enhanced the in vitro antimicrobial activity against P. aeruginosa in tilapia gills mucus and serum samples and decreased the bacterial load in vivo after infection with this Gram-negative bacterium. Our results evidenced, for the first time, a direct link between a growth hormone secretagogue ghrelin mimetic in fish and the enhancement of antimicrobial peptides transcription, which suggests that this secretagogue is capable to lead the activation of microbicidal activity in tilapia. Thus, these results open new possibilities for GHRP-6 application in aquaculture to stimulate the teleost immune system as an alternative treatment against opportunistic bacteria.

Promiscuous T cell epitopes boosts specific IgM immune response against a P0 peptide antigen from sea lice in different teleost species.

The development of vaccines employing conserved protein antigens, for instance ribosomal protein P0, has as disadvantage the high degree of identity between pathogen and host proteins due to possible induction of tolerance or auto antibodies in the host organism. To overcome this drawback, peptide-based vaccines have been designed with a proved high efficacy. The use of defined peptides as antigens has the problem that they are generally poor immunogenic unless coupled to a carrier protein. Several studies have established the potential for promiscuous T cell epitopes incorporated into chimeric peptides to enhance the immunogenicity in mammals. On the contrary, studies about the role of these epitopes on teleost immune system are scarce. Therefore, the main objective of our present study was to evaluate the potential of promiscuous T cell epitopes to boost specific IgM immune response in teleost fish against a peptide antigen. With this aim, we used a peptide of 35 amino acids from the ribosomal P0 protein of Lepeophtheirus salmonis, an important parasite in salmon aquaculture. We fused this peptide to the C-terminal of T cell epitopes from tetanus toxin and measles virus and produced the chimeric protein in Escherichia coli. Following vaccination, IgM antibody production was monitored in different immunization schemes in Tilapia, African catfish and Atlantic salmon. The results demonstrated for first time that the addition of T cell epitopes at the N-terminal of a target peptide increased IgM specific response in different teleost species, revealing the potential of this approach to develop peptide-based vaccines for aquaculture. The results are also of great importance in the context of vaccine development against sea lice using ribosomal protein P0 as antigen taking into account the key role of P0 in protein synthesis and other essential physiological processes.

Growth hormone releasing peptide-6 enhanced antibody titers against subunit antigens in mice (BALB/c), tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus).

Modern subunit vaccines have excellent safety profiles and improved tolerability, but do not elicit strong immune responses without the addition of adjuvants. Developing a safe and affective adjuvant remains a challenge for peptide-based vaccine design. Growth Hormone Releasing Peptide-6 (GHRP-6) is one of the earliest-developed, synthetic, peptidyl growth hormone secretagogue receptor agonists. These compounds mimic the effect of the endogenous ligand, ghrelin. In the present study, we evaluated the ability of GHRP-6 to enhance the humoral immune response against co-injected antigens in mice, tilapia and African catfish. This peptide was able to increase the antigen-specific antibody response using heterologous proteins and peptides as antigens, which were also formulated in "water in oil" emulsions (Freund and Montanide). As long as we know there is no previous report describing any ghrelin analogous as molecular immunomodulator stimulating a humoral immune response. Further studies will be conducted to evaluate the functionality of this humoral immune response in challenge trials.

Isquemia miocárdica silente en diabéticos tipo 2 / Silent myocardial ischemia in type 2 diabetes patients

Objetivos: determinar la frecuencia de isquemia miocárdica silente en diabéticos tipo 2 y su relación con el control metabólico. Métodos: se realizó un estudio descriptivo transversal en 79 pacientes asintomáticos con diabetes mellitus tipo 2 sin antecedentes de cardiopatía isquémica, hipertensión arterial o de ser fumador, que acudieron a la Consulta de Endocrinología del Hospital Militar Central Dr Carlos J Finlay, entre febrero de 2009 y febrero de 2011. Se les realizó ecocardiografía con doppler tisular y se determinaron los niveles de glucemia en ayunas, posprandial, hemoglobina glucosilada, colesterol y triglicéridos. Las variables clínicas analizadas en relación con la isquemia miocárdica silente fueron: edad, sexo, tiempo de evolución de la diabetes e índice de masa corporal. Para las variables cualitativas se utilizaron distribuciones de frecuencia con el cálculo del porcentaje y para establecer relación entre variables la prueba de chi cuadrado. Resultados: la edad media del total de pacientes fue de 54 años, de ellos el 69,1 por ciento correspondió al sexo masculino y el 31,9 por ciento al femenino. En el 20,2 por ciento de los pacientes se observaron signos de isquemia miocárdica por doppler tisular, y de ellos, un 75 por ciento tuvo niveles patológicos de colesterol total, con relación estadísticamente significativa (p= 0,01), sujetos que tuvieron 4,4 veces más riesgo relativo de presentar isquemia miocárdica, que los pacientes con colesterol normal. Las cifras de glucemia en ayunas, posprandial y hemoglobina glucosilada fueron significativamente mayor en el grupo con isquemia. Los pacientes con niveles elevados de glucemia en ayunas tuvieron 10,5 veces más riesgo de isquemia miocárdica que los que tenían cifras adecuadas. Igualmente, los casos con cifras elevadas de glucemia posprandial presentaron 12 veces más riesgo de enfermar. Conclusiones: la isquemia miocárdica silente es frecuente en los diabéticos tipo 2 y se relaciona con los niveles patológicos de colesterol y el mal control glucémico(AU)

Objectives: to determine the frequency of silent myocardial infarction in type 2 diabetes patients and its relation with the metabolic control. Methods: a cross-sectional descriptive study of 79 asymptomatic patients suffering type 2 diabetes mellitus and without a history of ischemic cardiopathy, blood hypertension or smoking. These patients were seen at the endocrinology service of Dr Carlos J Finlay from February 2009 to February 2011. They underwent Doppler tissue imaging echocardiography and their levels of glycemia on fasting, pospandrial glycemia, glycated haemoglobin, cholesterol and triglycerides were determined. The analyzed clinical variables lfor the silent myocardial ischemia were age, sex, time of evolution of diabetes and body mass index. Frequency distributions and percentage estimations were used for the qualitative variables whereas the Chi square test served to establish relationships among variables. Results: the average age of the patients was 54 years, 69,1 percent were males and 31,9 percent females. The Doppler tissue imaging echocardiography showed signs of myocardial ischemia in 20 percent of these patients, and 75 percent had pathological levels of total cholesterol with statistically significant relation (p=0.01) and their relative risk of developing myocardial ischemia was 4.4 times higher than the rest of patients with normal cholesterol. The values of glycemia on fasting, pospandrial glycemia and glycated haemoglobin were significantly higher than in the ischemic group. The patients having significantly higher values of glycemia on fasting exhibited a risk of myocardial ischemia that was 10.5 times higher than that of the patients with adequate values for this variable. Likewise, the risk of getting sick was 12 times higher in those cases with high values of pospandrial glycemia. Conclusions: silent myocardial ischemia is frequent in type 2 diabetes mellitus patients and is associated with pathological levels of cholesterol and with poor glycemic control(AU)

Asociación entre prácticas en salud, somatización y algunos factores psicosociales en usuarios de clínicas de ASSBASALUD ESE: Manizales (Colombia), 2007 / Association between health practices, somatization and some psychosocial factors in clinics of ASSBASALUD ESE: Manizales (Colombia), 2007

Introducción: La evidencia investigativa sugiere que la población con una patología médica crónica presenta mayor riesgo de desarrollar un cuadro de somatización, definida como una serie de síntomas corporales sin causa orgánica demostrable, y asociada al estrés y cuadros depresivos, ansiosos, que generalmente pasan desapercibidos en la consulta. Este tipo de pacientes terminan convirtiéndose en consultantes crónicos o en abusadores de servicios de salud, lo que genera congestión en la prestación del servicio e incremento en los costos de salud. Metodología: Estudio de corte transversal, con 188 pacientes que asistieron a consultaexterna en los diferentes centros urbanos de Atención en Seguridad Social, Bienestar y Salud, Empresa Social del Estado (ASSBASALUD, ESE) del área urbana de Manizales (Colombia). Resultados: La edad promedio fue 51,3 años, 62,5 por ciento presentaban somatización, 61,9 por ciento ansiedad subclínica, 51,6 por ciento no presentaban depresión, estrés bajo 73,6 por ciento y buena función familiar 42,9 por ciento . Se encontró dependencia significativa entre somatización y ansiedad (p=0,000), depresión (p=0,005) estrés (p=0,000) funcionalidad familiar (p=0,007), entre otras. También se encontró dependencia significativa entre las variables prácticas en salud y somatización (p=0.002), Ansiedad (p=0,014), depresión (p=0.008) a nivel p<0,1 con funcionalidad familiar (p=0,093). Conclusiones: se encontró una alta comorbilidad de somatización en los pacientes con algún grado de depresión, ansiedad y estrés, al igual que deficientes prácticas de salud en este tipo de pacientes.