ABSTRACT: Two groups of rats were fed either a high salt diet or a low salt diet. This study aims to look at salt intake in correlation to altering other metabolites and the onset of hypertension
Project description:Several studies have established a link between high-salt diet, inflammation, and hypertension. Vitamin D supplementation has shown anti-inflammatory effects in many diseases; gut microbiota is also associated with a wide variety of cardiovascular diseases, but potential role of vitamin D and gut microbiota in high-salt diet-induced hypertension remains unclear. Therefore, we used rats with hypertension induced by a high-salt diet as the research object and analyzed the transcriptome of their tissues (kidney and colon) and gut microbiome to conduct an overall analysis of the gut–kidney axis. We aimed to confirm the effects of high salt and calcitriol on the gut–kidney immune system and the composition of the intestinal flora. We demonstrate that consumption of a high-salt diet results in hypertension and inflammation in the colon and kidney and alteration of gut microbiota composition and function. High-salt diet-induced hypertension was found to be associated with seven microbial taxa and mainly associated with reduced production of the protective short-chain fatty acid butyrate. Calcitriol can reduce colon and kidney inflammation, and there are gene expression changes consistent with restored intestinal barrier function. The protective effect of calcitriol may be mediated indirectly by immunological properties. Additionally, the molecular pathways of the gut microbiota-mediated BP regulation may be related to circadian rhythm signals, which needs to be further investigated. An innovative association analysis of the microbiota may be a key strategy to understanding the association between gene patterns and host.
Project description:We wanted to understand how a salt restriction diet could improve cardiac damage (ie cardiac hypertrophy, fibrosis, hypertension) in a rat model of metabolic syndrome. We thus performed an Agilent microarray experiment in order to identify expression variations in left ventricles of rats having a normal sodium diet (0,64%) or a low sodium diet (less than 0,01%)
Project description:Supporting microarray data for manuscript entitled "OSTEOPONTIN AND PAI-1 EXPRESSION IN MALIGNANT HYPERTENSION: SUPPRESSION BY p38 MAPK INHIBITORS" submitted to the HYPERTENSION journal. Experiment Overall Design: Male spontaneously hypertensive stroke-prone rats (SHR-SP) were obtained from Charles River (Raleigh, NC). At 11 weeks of age, the SHR-SP were randomized into 2 groups, and fed either powdered chow diet (Purina 5001) with water ad lib; or a high-salt/high-fat diet consisting of 1% NaCl in the drinking water and 24.5% fat in the chow (from Harlan TekLad, Madison, Wisconsin). 6 replicate animals per diet per time point.
Project description:Background. The Dahl salt-sensitive (SS) rat is an established model of salt-sensitive hypertension and renal damage. Recently, sodium-independent dietary effects were shown to be important in the development of the SS hypertensive phenotype. Compared to Dahl SS/JrHsdMcwi (SS/MCW) rats fed a purified diet (AIN-76A), grain-fed Dahl SS/JrHsdMcwiCrl rats (SS/CRL; Teklad 5L2F) were less susceptible to salt-induced hypertension and renal damage. Methods. With the known role of the immune system in hypertension, the present study characterized the immune cells infiltrating SS/MCW and SS/CRL kidneys. To further identify distinct molecular pathways between SS/MCW and SS/CRL, transcriptomic analysis was performed via RNA sequencing in T-cells isolated from the blood and kidneys of low and high salt-fed rats. Results. Following a 3-week high salt (4.0% NaCl) challenge, SS/CRL rats were protected from salt-induced hypertension (116.5±1.2 vs 141.9±14.4 mmHg) and albuminuria (21.7±3.5 vs 162.9±22.2 mg/day) compared to SS/MCW. Additionally, the absolute number of immune cells infiltrating the kidney was significantly reduced in SS/CRL. RNA-seq revealed >50% of all annotated genes in the entire transcriptome to be significantly differentially expressed in T-cells isolated from blood versus kidney. Pathway analysis of significant differentially expressed genes between SS/MCW and SS/CRL renal and circulating T-cells demonstrated salt-induced changes in genes related to inflammation in SS/MCW compared to metabolism-related pathways in SS/CRL. Conclusions. These functional and transcriptomic T-cell differences between SS/MCW and SS/CRL show that sodium-independent dietary effects may influence the immune response and infiltration of immune cells into the kidney, ultimately impacting susceptibility to salt-induced hypertension and renal damage.
Project description:In the present study we made use of the (1-renin) DOCA-salt mouse model - which has been previously shown to develop cardiac and renal hypertrophy - to evaluate the direct effects of high-salt diet on cardiac function and gene expression profiling. The comparison between low-salt and high-salt DOCA-treated mice will reveal what genes are directly modulated by sodium in (normotensive) DOCA-treated mice. Previous publications: Wang Q, Hummler E, Nussberger J, Clement S, Gabbiani G, Brunner HR, Burnier M. Blood pressure, cardiac, and renal responses to salt and deoxycorticosterone acetate in mice: role of renin genes. J Am Soc Nephrol. 2002;13:1509 –1516. Wang Q, Domenighetti AA, Pedrazzini T, Burnier M. Potassium supplementation reduces cardiac and renal hypertrophy independent of blood pressure in DOCA/salt mice. Hypertension. 2005 Sep;46(3):547-54. Keywords: comparative dose-response treatment (2 groups)
Project description:High salt diets have recently been implicated in hypertension, cardiovascular disease and autoimmune disease. However, whether and how dietary salt affects host antiviral response remain elusive. Here, we report that high salt induces an instant reduction in host antiviral immunity, although this effect is compromised during a long-term high salt diet.
Project description:Dahl-Iwai (DI) salt-sensitive rats were studied using microarrays to identify gender-specific differences in the kidney, both basal differences and responses to a high salt diet. In DI rat kidneys, gene expression profiles demonstrated inflammatory and fibrotic responses selectively in females. Gonadectomy of DI rats abrogated gender differences in gene expression. Gonadectomized female and gonadectomized male DI rats both responded to high salt with the same spectrum of gene expression changes as intact female DI rats. Androgens dominated the gender selective responses to salt. Several androgen-responsive genes were identified with roles potentiating the differential responses to salt including increased male expression of Angiotensin-Vasopressin Receptor and Prolactin Receptor, decreased 5-alpha reductase, and mixed increases and decreases in expression of Cyp4a- genes that can produce eicosanoid hormones. These gender differences potentiate sodium retention by males, and increase kidney function during gestation by females. Keywords: Disease-State Analysis (Salt-Sensitive Hypertension)
Project description:To identify the effect of high-salt diet on immune cells of brain tissues, we isolated immune cells of brain from mice fed with control diet or high-salt diet.
Project description:Serum and glucocorticoid-induced kinase 1 (SGK1) activates the epithelial sodium channel (eNaC) in tubules. We examined renal SGK1 abundance in salt-adaptation and in salt-sensitive hypertension. Sprague-Dawley and Dahl salt-sensitive rats were placed on either 8% or 0.3% NaCl diets for 10 days. Plasma aldosterone levels were approximately 2.5-fold greater on 0.3% versus 8% NaCl diets in both rat strains. Both serum and glucocorticoid-induced kinase 1 transcript and protein abundance were less (P<0.01) in Sprague-Dawley rats and greater (P<0.01) in Dahl salt-sensitive rats on 8% versus 0.3% NaCl diets. The cDNA sequences of serum and glucocorticoid-induced kinase 1 in both strains of rat were the same. The present results provide evidence that the abundance of serum and glucocorticoid-induced kinase 1 in rat kidney may play a role in salt adaptation and the pathogenesis of hypertension and suggests that aldosterone is not the primary inducer of SGK1 in the Sprague-Dawley rat. Keywords = Rattus norvegicus, Sprague Dawley, Dahl SS/Jr, kidney, NaCl diet Keywords: other