The Dual AngII/AVP Receptor Gene N119S/C163R Variant Exhibits Sodium-Induced Dysfunction and Cosegregates With Salt-Sensitive Hypertension in the Dahl Salt-Sensitive Hypertensive Rat Model

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A Functional 12T-insertion polymorphism in the <i>ATP1A1</i> promoter confers decreased susceptibility to hypertension in a male Sardinian population

Identification of susceptibility genes for essential hypertension in humans has been a challenge due to its multifactorial pathogenesis complicated by gene-gene and gene-environment interactions, developmental programing and sex specific differences. These concurrent features make identification of causal hypertension susceptibility genes with a single approach difficult, thus requiring multiple lines of evidence involving genetic, biochemical and biological experimentation to establish causal functional mutations. Here we report experimental evidence encompassing genetic, biochemical and in vivo modeling that altogether support ATP1A1 as a hypertension susceptibility gene in males in Sardinia, Italy. ATP1A1 encodes the α1Na,K-ATPase isoform, the sole sodium pump in vascular endothelial and renal tubular epithelial cells. DNA-sequencing detected a 12-nucleotide long thymidine (12T) insertion(ins)/deletion(del) polymorphism within a poly-T sequence (38T vs 26T) in the ATP1A1 5’-regulatory region associated with hypertension in a male Sardinian population. The 12T-insertion allele confers decreased susceptibility to hypertension (P = 0.035; OR = 0.50 [0.28–0.93]) accounting for 12.1 mmHg decrease in systolic BP (P = 0.02) and 6.6 mmHg in diastolic BP (P = 0.046). The ATP1A1 promoter containing the 12T-insertion exhibited decreased transcriptional activity in in vitro reporter-assay systems, indicating decreased α1Na,K-ATPase expression with the 12T-insertion, compared with the 12T-deletion ATP1A1 promoter. To test the effects of decreased α1Na,K-ATPase expression on blood pressure, we measured blood pressure by radiotelemetry in three month-old, highly inbred heterozygous knockout ATP1A1+/− male mice with resultant 58% reduction in ATP1A1 protein levels. Male ATP1A1+/− mice showed significantly lower blood pressure (P &#60; 0.03) than age-matched male wild-type littermate controls. Concordantly, lower ATP1A1 expression is expected to lower Na-reabsorption in the kidney thereby decreasing sodium-associated risk for hypertension and sodium-induced endothelial stiffness and dysfunction. Altogether, data support ATP1A1 as a hypertension susceptibility gene in a male Sardinian population, and mandate further investigation of its involvement in hypertension in the general population

Sex-specific effects of NLRP6/AVR and ADM <i>loci</i> on susceptibility to essential hypertension in a Sardinian population

Coronary artery disease, heart failure, fatal arrhythmias, stroke, and renal disease are the most common causes of mortality for humans, and essential hypertension remains a major risk factor. Elucidation of susceptibility loci for essential hypertension has been difficult because of its complex, multifactorial nature involving genetic, environmental, and sex- and age-dependent nature. We investigated whether the 11p15.5 region syntenic to rat chromosome 1 region containing multiple blood pressure quantitative trait loci (QTL) detected in Dahl rat intercrosses harbors polymorphisms that contribute to susceptibility/resistance to essential hypertension in a Sardinian population. Initial testing performed using microsatellite markers spanning 18 Mb of 11p15.5 detected a strong association between D11S1318 (at 2.1 Mb, P = 0.004) and D11S1346 (at 10.6 Mb, P = 0.00000004), suggesting that loci in close proximity to these markers may contribute to susceptibility in our Sardinian cohort. NLR family, pyrin domain containing 6/angiotensin-vasopressin receptor (NLRP6/AVR), and adrenomedullin (ADM) are in close proximity to D11S1318 and D11S1346, respectively; thus we tested single nucleotide polymorphisms (SNPs) within NLRP6/AVR and ADM for their association with hypertension in our Sardinian cohort. Upon sex stratification, we detected one NLRP6/AVR SNP associated with decreased susceptibility to hypertension in males (rs7948797G, P = 0.029; OR = 0.73 [0.57-0.94]). For ADM, sex-specific analysis showed a significant association between rs4444073C, with increased susceptibility to essential hypertension only in the male population (P = 0.006; OR = 1.44 [1.13-1.84]). Our results revealed an association between NLRP6/AVR and ADM loci with male essential hypertension, suggesting the existence of sex-specific NLRP6/AVR and ADM variants affecting male susceptibility to essential hypertension

Marcadores de inflamación y perfil lipídico en pacientes obesos

La obesidad es una enfermedad metabólica asociada a insulinorresistencia (IR) y a un estado proinflamatorio, constituyendo un factor de riesgo de diabetes tipo 2 y enfermedad cardiovascular. En condiciones de obesidad, el tejido adiposo sufre una remodelación que favorece la síntesis de adipoquinas proinflamatorias y reactantes de fase aguda que promueven una inflamación crónica de bajo grado. El objetivo de este trabajo fue estudiar los niveles plasmáticos de Fibrinógeno (Fg), PCR ultrasensible (uPCR), TNF-α y mieloperoxidasa (MPO) en pacientes obesos y su correlación con IR e índices antropométricos. Se estudiaron 54 pacientes obesos (20M/34F), de 48±11años, que fueron comparados con 20 individuos sanos de sexo y edades semejantes. En ambos grupos se midió peso, talla, circunferencia de cintura (CC), se calculó el índice de masa corporal (IMC) y se determinó: glucemia y perfil lipídico (Wiener Lab), TNF-α (R&D Systems), MPO (Binding Site Ltd.), Fg (Diag.Stago), Insulina (ECLIA) y se calculó el HOMA. Los datos se analizaron con el programa SPSS 25 y se expresaron como la media±DS. Se consideró significativo un p<0,05. Los pacientes obesos, presentaron valores aumentados de: Fg (385±117 vs. 275±32 mg/dl, p=0,004); uPCR (7,4±5,6 vs. 1,4±1,6 m/dl, p=0,001); Insulina (23±16 vs. 7,2±2,4 uUI/ml, p=0,001), HOMA (5,2±3,9 vs. 2,1±0,3 p=0,001), Colesterol total (223±47 vs. 187±22 mg/dl, p=0,04) y LDL-C (150±45 vs.118±49 mg/dl, p=0,046). Sin embargo, los valores de TNF-α y MPO no mostraron diferencias significativas con los controles. El IMC se correlacionó positivamente con insulina, HOMA, Fg y uPCR, mientras que el CC lo hizo con insulina, HOMA y uPCR. Los resultados sugieren la presencia de un estado inflamatorio de bajo grado asociado a IR en pacientes obesos.Fil: Aleman, Mariano Nicolás. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Luciardi, María Constanza. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Díaz, E. L.. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; ArgentinaFil: Mariani, A. C.. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; ArgentinaFil: Herrera, Héctor Matías. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Albornoz, Estela Roxana. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; ArgentinaFil: Valdez, M. E.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Abregu, Adela Victoria. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Bioquímica Clinica Aplicada. Cátedra de Practica Profesional; ArgentinaXXXVI Jornadas Científicas de la Asociación de Biología de TucumánArgentinaAsociación de Biología de Tucumá

Restructuring of Pancreatic Islets and Insulin Secretion in a Postnatal Critical Window

Function and structure of adult pancreatic islets are determined by early postnatal development, which in rats corresponds to the first month of life. We analyzed changes in blood glucose and hormones during this stage and their association with morphological and functional changes of alpha and beta cell populations during this period. At day 20 (d20), insulin and glucose plasma levels were two- and six-fold higher, respectively, as compared to d6. Interestingly, this period is characterized by physiological hyperglycemia and hyperinsulinemia, where peripheral insulin resistance and a high plasmatic concentration of glucagon are also observed. These functional changes were paralleled by reorganization of islet structure, cell mass and aggregate size of alpha and beta cells. Cultured beta cells from d20 secreted the same amount of insulin in 15.6 mM than in 5.6 mM glucose (basal conditions), and were characterized by a high basal insulin secretion. However, beta cells from d28 were already glucose sensitive. Understanding and establishing morphophysiological relationships in the developing endocrine pancreas may explain how events in early life are important in determining adult islet physiology and metabolism

Application of new indicators to assess the quality of antimicrobial use in intensive care units

This study explored the feasibility of a bundle of indicators aimed at assessing the quality of antimicrobial use in intensive care units (ICUs) through an observational prospective study spanning 12 quarters (January 2019-December 2021) in a 1290-bed teaching hospital in Spain. Members of the antimicrobial stewardship programme team selected the indicators to analyse the quality of antimicrobial use based on consumption data from a list proposed in a previous study. Antimicrobial use in the ICU was measured as defined daily dose (DDD) per 100 occupied bed-days. Trends and points of change were analysed with segmented regression. The intravenous macrolides/intravenous respiratory fluoroquinolones ratio in the ICU increased progressively, although not significantly, by 11.14% per quarter, likely related to prioritization of the use of macrolides in serious community-acquired pneumonia and the coronavirus disease 2019 pandemic. A remarkable upward trend of 2.5% per quarter was detected in the anti-methicillin-susceptible Staphylococcus aureus/anti-methicillin-resistant S. aureus agents ratio in the ICU, which could be explained by the low prevalence of methicillin-resistant S. aureus at the study centre. Patterns of amoxicillin-clavulanic acid/piperacillin-tazobactam ratio and diversification of anti-pseudomonal beta-lactams showed an increment in use over the study. The use of these novel indicators provides additional information for the current analysis of DDD. Implementation is feasible, and led to the detection of patterns that agree with local guidelines and cumulative antibiogram reports, and foster targeted improvement actions within antimicrobial stewardship programmes.A.B.G. receives financial support from Subprograma Juan Rodés, Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spain (JR21/00017). G.P. receives a grant from the Plan Andaluz de Investigación, Desarrollo e Innovación, Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía, Spain (Grant PAIDI2020/POSTDOC_21_00831). L.H. and M.M. receive financial support from Subprograma Río Hortega, Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spain (CM19/00152 and CM21/00115).Peer reviewe

Validation of <i>N</i>-myristoyltransferase as Potential Chemotherapeutic Target in Mammal-Dwelling Stages of <i>Trypanosoma cruzi</i>

BACKGROUND:Trypanosoma cruzi causes Chagas disease, an endemic and debilitating illness in Latin America. Lately, owing to extensive population movements, this neglected tropical disease has become a global health concern. The two clinically available drugs for the chemotherapy of Chagas disease have rather high toxicity and limited efficacy in the chronic phase of the disease, and may induce parasite resistance. The development of new anti-T. cruzi agents is therefore imperative. The enzyme N-myristoyltransferase (NMT) has recently been biochemically characterized, shown to be essential in Leishmania major, Trypanosoma brucei, and T. cruzi¸ and proposed as promising chemotherapeutic target in these trypanosomatids. METHODOLOGY/PRINCIPAL FINDINGS:Here, using high-content imaging we assayed eight known trypanosomatid NMT inhibitors, against mammal-dwelling intracellular amastigote and trypomastigote stages and demonstrated that three of them (compounds 1, 5, and 8) have potent anti-proliferative effect at submicromolar concentrations against T. cruzi, with very low toxicity against human epithelial cells. Moreover, metabolic labeling using myristic acid, azide showed a considerable decrease in the myristoylation of proteins in parasites treated with NMT inhibitors, providing evidence of the on-target activity of the inhibitors. CONCLUSIONS/SIGNIFICANCE:Taken together, our data point out to the potential use of NMT inhibitors as anti-T. cruzi chemotherapy

CHIME/FRB Discovery of 25 Repeating Fast Radio Burst Sources

We present the discovery of 25 new repeating fast radio burst (FRB) sources found among CHIME/FRB events detected between 2019 September 30 and 2021 May 1. The sources were found using a new clustering algorithm that looks for multiple events co-located on the sky having similar dispersion measures (DMs). The new repeaters have DMs ranging from $\sim$220 pc cm$^{-3}$ to $\sim$1700 pc cm$^{-3}$, and include sources having exhibited as few as two bursts to as many as twelve. We report a statistically significant difference in both the DM and extragalactic DM (eDM) distributions between repeating and apparently nonrepeating sources, with repeaters having lower mean DM and eDM, and we discuss the implications. We find no clear bimodality between the repetition rates of repeaters and upper limits on repetition from apparently nonrepeating sources after correcting for sensitivity and exposure effects, although some active repeating sources stand out as anomalous. We measure the repeater fraction and find that it tends to an equilibrium of $2.6_{-2.6}^{+2.9}$% over our exposure thus far. We also report on 14 more sources which are promising repeating FRB candidates and which merit follow-up observations for confirmation.Comment: Submitted to ApJ. Comments are welcome and follow-up observations are encouraged