Genetic Regulation of Redox Balance in ß-Thalassemia Trait.

ß-Thalassemia (ß-thal) trait is a heterogeneous group of genetic defects leading to decreased ß-globin production, ineffective erythropoiesis, and oxidative stress. The aim is to evaluate the cytoprotective response, at transcriptional and systemic levels, of the variations of global redox balance in ß-thal trait patients. Sixty-six subjects (40 healthy and 26 with ß-thal trait) were analyzed at the Universidad Nacional de Tucumán, Tucumán, Argentina, between 2016 and 2017. The following parameters were evaluated: complete blood count, iron status, hemoglobin (Hb) electrophoresis, Hb A2, thiobarbituric acid reactive species (TBARS), serum catalase (CAT), and superoxide dismutase (SOD) activity, FOXO3a, NRF2, SOD, PRDX2, CAT, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) gene expression. The ß-thal trait group showed a decrease in Hb levels, MCV, and MCH with higher TBARS levels. The SOD activity was significantly increased by 32.0% in ß-thal trait patients respect to the control group. Relative expression of NRF2 was 4.7-fold higher in ß-thal trait than in the control group, while FOXO3a expression was similar in both groups. The SOD, PRDX2, and proinflammatory cytokines transcriptional expression was significantly upregulated in ß-thal trait patients. This is the first study on the genetic regulation of redox balance in ß-thal trait patients in which interesting modifications were observed in the transcript levels of some redox regulators that could be associated with changes in the erythrocyte proteome in this disorder. A better understanding of the pathophysiological mechanisms present in these heterozygous patients would allow adequate therapy in situations such as growth, pregnancy, or high performance sports, favoring a personalized treatment.

Lactobacillus casei beneficially modulates immuno-coagulative response in an endotoxemia model.

: The current study aims at evaluating the effect of the oral administration of Lactobacillus casei CERELA (CRL) 431 on parameters implicated in inflammation-coagulation interaction using a model of acute inflammation induced by lipopolysaccharide (LPS) in mice. Six-week-old Balb/c mice were treated with L. casei for 5 consecutive days. Then treated and untreated mice received an LPS injection (L. casei + LPS and LPS groups, respectively). Liver and kidney were removed, blood samples were obtained, and hemostatic and inflammatory parameters were evaluated at different times post LPS injection. Preventive L. casei administration induced a significant decrease in proinflammatory TNF-α and IL-6 cytokines by decreasing tissue factor expression in liver and kidney. Moreover, the lower expression of tissue factor in the L. casei + LPS group led to a lower activation of the coagulation system, which was observed by the fast systemic restoration of factors VII and V coagulation factors and antithrombin levels. This study highlights the capacity of L. casei to modulate the hemostatic unbalance in an acute endotoxemia model. Our findings showed the ability of L. casei CRL 431 to regulate the immuno-coagulative response. This fact could be helpful to propose new adjunctive strategies addressed to the restoration of physiological anticoagulant mechanisms in sepsis patients.

Molecular characterization and phenotypical study of ß-thalassemia in Tucumán, Argentina.

The main hereditary hemoglobin (Hb) disorder in Argentina is ß-thalassemia (ß-thal). Molecular studies performed in the center of the country exhibited a marked prevalence of the codon 39 (C > T) and IVS-I-110 (G > A) mutations. The northwest region of Argentina has a different demographic history characterized by an important Spanish influx. Seventy-one ß-thal carriers attending the Instituto de Bioquímica Aplicada, Tucumán, Argentina, were investigated for ß-globin gene mutations by real-time polymerase chain reaction (RT-PCR). To examine the genotype-phenotype relationship, mean corpuscular volume (MCV), mean corpuscular Hb (MCH) and Hb A2 were measured. In order to recognize ß-thal, Mentzer Index, Shine & Lal and Red Cell Distribution Width Index (RDWI), were calculated. The ethnic background of subjects revealed that 82.0% of the population was of Italian, Spanish and Arab origin. Seven mutations were detected: codon 39 (45.0%), IVS-I-1 (G > A) (22.5%), IVS-I-110 (16.3%), IVS-II-1 (G > A) (4.1%), IVS-I-1 (G > T) (2.0%), IVS-I-6 (T > C) (2.0%) and IVS-II-745 (G > C) (2.0%). In three families (6.1%), ß-thal mutations were not determined. These results differed from other Argentinian studies because at present codon 39 and IVS-I-1 are the most prevalent; MCV, MCH and Hb A2 did not correlate with the type of mutation (ß(0)/ß(+)). Values of MCV (67.0 fL) and Hb A2 (4.85%) were unable to discriminate between them. Significant differences (p < 0.05) in MCV, MCH and Shine & Lal were observed between the undetermined group and the three most common mutations. These data show different patterns of ß-thal mutations in the center and northwest regions of Argentina. Differences might represent the influence of Spanish immigration.

Cloning and functional characterization of two key enzymes of glycosphingolipid biosynthesis in the amphibian Xenopus laevis.

Gangliosides are a subfamily of complex glycosphingolipids (GSLs) with important roles in many biological processes. In this study, we report the cDNA cloning, functional characterization, and the spatial and temporal expression of Xlcgt and Xlgd3 synthase during Xenopus laevis development. Xlcgt was expressed both maternally and zigotically persisting at least until stage 35. Maternal Xlgd3 synthase mRNA could not be detected and showed a steady-state expression from gastrula to late tailbud stage. Xlcgt is mainly present in involuted paraxial mesoderm, neural folds, and their derivatives. Xlgd3 synthase transcripts were detected in the dorsal blastoporal lip, in the presumptive neuroectoderm, and later in the head region, branchial arches, otic and optic primordia. We determined the effect of glycosphingolipid depletion with 1-phenyl-2-palmitoyl-3-morpholino-1-propanol (PPMP) in mesodermal layer. PPMP-injected embryos showed altered expression domains in the mesodermal markers. Our results suggest that GSL are involved in convergent-extension movements during early development in Xenopus.