Hormones, food, stress and infections: their etiological role in autoimmune diseases

Introduction: The etiology of autoimmune diseases is still unknown, but different causes arise. Objective: To describe the role of hormones, diet, stress and infections in the etiology of autoimmune diseases. Methods: A bibliographic review was made using the Google Scholar and articles of free access in the Pubmed and Scielo database from 2015 to 2019. The search terms were used according to the DeCS and MeSH descriptors. Development: It is well known that female hormones increase the risk of autoimmune diseases. Stress can maintain low-grade chronic inflammatory responses that cause tissue damage, initiating or aggravating the clinical manifestations of autoimmunity. An adequate diet allows the guests of the intestinal microbiota to maintain the homeostasis of the immune system. Today, glutamate is used as a flavor enhancer, especially in developed countries. Perhaps it is one of the causes of the higher incidence of autoimmune diseases in these regions. Conclusions: Autoimmune diseases are more frequent in women. Adequate nutrition allows the gut microbiota not to be altered and to maintain immunological homeostasis. Infections and stress situations can trigger or exacerbate the clinical manifestations of autoimmunity(AU)

Neurochemical and behavioral characterization of neuronal glutamate transporter EAAT3 heterozygous mice

BACKGROUND: Obsessive-compulsive disorder (OCD) is a severe neuropsychiatric condition affecting 1-3% of the worldwide population. OCD has a strong genetic component, and the SLC1A1 gene that encodes neuronal glutamate transporter EAAT3 is a strong candidate for this disorder. To evaluate the impact of reduced EAAT3 expression in vivo, we studied male EAAT3 heterozygous and wild-type littermate mice using a battery of behavioral paradigms relevant to anxiety (open field test, elevated plus maze) and compulsivity (marble burying), as well as locomotor activity induced by amphetamine. Using high-performance liquid chromatography, we also determined tissue neurotransmitter levels in cortex, striatum and thalamus-brain areas that are relevant to OCD. RESULTS: Compared to wild-type littermates, EAAT3 heterozygous male mice have unaltered baseline anxiety-like, compulsive-like behavior and locomotor activity. Administration of acute amphetamine (5 mg/kg intraperitoneally) increased locomotion with no differences across genotypes. Tissue levels of glutamate, GABA, dopamine and serotonin did not vary between EAAT3 heterozygous and wild-type mice. CONCLUSIONS: Our results indicate that reduced EAAT3 expression does not impact neurotransmitter content in the corticostriatal circuit nor alter anxiety or compulsive-like behaviors.

Genetic polymorphisms in the glutamate-rich protein of Plasmodium falciparum field isolates from a malaria-endemic area of Brazil

The genetic diversity displayed by Plasmodium falciparum, the most deadly Plasmodium species, is a significant obstacle for effective malaria vaccine development. In this study, we identified genetic polymorphisms in P. falciparum glutamate-rich protein (GLURP), which is currently being tested in clinical trials as a malaria vaccine candidate, from isolates found circulating in the Brazilian Amazon at variable transmission levels. The study was performed using samples collected in 1993 and 2008 from rural villages situated near Porto Velho, in the state of Rondônia. DNA was extracted from 126 P. falciparum-positive thick blood smears using the phenol-chloroform method and subjected to a nested polymerase chain reaction protocol with specific primers against two immunodominant regions of GLURP, R0 and R2. Only one R0 fragment and four variants of the R2 fragment were detected. No differences were observed between the two time points with regard to the frequencies of the fragment variants. Mixed infections were uncommon. Our results demonstrate conservation of GLURP-R0 and limited polymorphic variation of GLURP-R2 in P. falciparum isolates from individuals living in Porto Velho. This is an important finding, as genetic polymorphisms in B and T-cell epitopes could have implications for the immunological properties of the antigen.

Prevalência de dislipidemia em adultos de meia-idade com polimorfismo do gene NOS3 e baixa aptidão cardiorrespiratória / Prevalence of dyslipidemia in middle-aged adults with NOS3 gene polymorphism and low cardiorespiratory fitness

OBJETIVO: Analisar a influência da associação dos polimorfismos do gene da sintase do óxido nítrico endotelial (NOS3) para as posições -786T>C, Glu298Asp e íntron 4b/a e a aptidão cardiorrespiratória sobre as concentrações de nitrito/nitrato, pressão arterial, perfil lipídico e prevalência de doenças cardiometabólicas em adultos. SUJEITOS E MÉTODOS: Noventa e duas pessoas foram divididas de acordo com o genótipo: não polimórficas (NP) e polimórficas (P). Posteriormente, foram subdivididas pela aptidão cardiorrespiratória associada ao genótipo: alta (ANP e AP) ou baixa (BNP e BP). RESULTADOS: Os indivíduos que apresentavam polimorfismo para as posições Glu298Asp+Íntron 4b/a e Glu298Asp+-786T>C e baixa aptidão cardiorrespiratória apresentaram maiores valores de colesterol total e maior prevalência de dislipidemia. CONCLUSÃO: Nossos dados demonstram que os polimorfismos do gene da NOS3 para essas duas associações influenciam os níveis de colesterol plasmático, e essa associação foi mais claramente observada quando os indivíduos apresentavam menor nível de aptidão cardiorrespiratória.

OBJECTIVE: To evaluate the influence of the interaction between endothelial nitric oxide synthase gene (NOS3) polymorphisms at positions -786T>C, Glu298Asp and intron 4b/a, and cardiorespiratory fitness on plasma nitrite/nitrate levels, blood pressure, lipid profile, and prevalence of cardiometabolic disorders. SUBJECTS AND METHODS: Ninety-two volunteers were genotyped for NOS3 polymorphisms at positions (-786T>C and Glu298Asp) and (intron 4b/a) and divided according to the genotype: non-polymorphic (NP) and polymorphic (P). After that, they were subdivided according to the cardiorespiratory fitness associated with genotype: high (HNP and HP) and low (LNP and LP). RESULTS: The subjects with polymorphism for the interactions at positions Glu298Asp + intron 4b/a, and Glu298Asp+-786T>C showed the highest values in total cholesterol, as well as dyslipidemia. CONCLUSION: Our findings show that NOS3 gene polymorphisms at positions -786T>C, Glu298Asp, and intron 4b/a exert negative effects on the lipid profile compared with those who do not carry polymorphisms.

Hb G Makassar (beta 6:Glu-Ala) in a Thai family.

Hemoglobin G Makassar was identified in a family of Thai origin, which was found to share identical properties with hemoglobin S in routine hemoglobin separation both by cellulose acetate electrophoresis and cation-exchange HPLC. It is, therefore, subjects with hemoglobin G Makassar and hemoglobin S who may sometimes be mistakenly identified for each other. In this study, identification of hemoglobin G Makassar was achieved by DNA sequence analysis, which revealed a single nucleotide substitution GAG-->GCG at codon 6 of the beta-globin gene. The hemoglobin variant was hemoglobin G Makassar [beta 6:Glu-->Ala]. This is the first report of hemoglobin G Makassar in Thailand.