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The pathogenesis of hypertension is known to involve a diverse range of contributing factors including genetic, environmental, hormonal, hemodynamic and inflammatory forces, to name a few. There is mounting evidence to suggest that the gut microbiome plays an important role in the development and pathogenesis of hypertension. The gastrointestinal tract, which houses the largest compartment of immune cells in the body, represents the intersection of the environment and the host. Accordingly, lifestyle factors shape and are modulated by the microbiome, modifying the risk for hypertensive disease. One well-studied example is the consumption of dietary fibers, which leads to the production of short-chain fatty acids and can contribute to the expansion of anti-inflammatory immune cells, consequently protecting against the progression of hypertension. Dietary interventions such as fasting have also been shown to impact hypertension via the microbiome. Studying the microbiome in hypertensive disease presents a variety of unique challenges to the use of traditional model systems. Integrating microbiome considerations into preclinical research is crucial, and novel strategies to account for reciprocal host-microbiome interactions, such as the wildling mouse model, may provide new opportunities for translation. The intricacies of the role of the microbiome in hypertensive disease is a matter of ongoing research, and there are several technical considerations which should be accounted for moving forward. In this review we provide insights into the host-microbiome interaction and summarize the evidence of its importance in the regulation of blood pressure. Additionally, we provide recommendations for ongoing and future research, such that important insights from the microbiome field at large can be readily integrated in the context of hypertension.

CKD is characterized by a sustained proinflammatory response of the immune system, promoting hypertension and cardiovascular disease. The underlying mechanisms are incompletely understood but may be linked to gut dysbiosis. Dysbiosis has been described in adults with CKD; however, comorbidities limit CKD-specific conclusions.We analyzed the fecal microbiome, metabolites, and immune phenotypes in 48 children (with normal kidney function, CKD stage G3-G4, G5 treated by hemodialysis [HD], or kidney transplantation) with a mean±SD age of 10.6±3.8 years.Serum TNF-Gut barrier dysfunction and microbial metabolite imbalance apparently mediate the proinflammatory immune phenotype, thereby driving the susceptibility to cardiovascular disease. The data highlight the importance of the microbiota-immune axis in CKD, irrespective of confounding comorbidities.

Chronic kidney disease (CKD) is characterized by a sustained pro-inflammatory response. The underlying mechanisms are incompletely understood, but may be linked to gut dysbiosis. Dysbiosis has been described in adults with CKD; however, comorbidities limit CKD-specific conclusions. We analyzed the fecal microbiome, metabolites and immune phenotypes in children at three different CKD stages (G3-G4, G5 (hemodialysis), after kidney transplantation) and healthy controls. Serum TNF-α and sCD14 were stage-dependently elevated, indicating inflammation and gut barrier dysfunction. We observed microbiome alterations in CKD, including a diminished production of short-chain fatty acids. Bacterial tryptophan metabolites were increased in CKD. CKD serum activated the aryl hydrocarbon receptor and stimulated TNF-α production by monocytes, corresponding to a shift towards intermediate/non-classical monocytes. Unsupervised T cell analysis revealed pro-inflammatory shifts in MAIT and Treg cells. Thus, gut barrier dysfunction and microbial metabolites exacerbate inflammation and may therefore contribute to the increased cardiovascular burden in CKD.

AIMS: Hypertension (HTN) can lead to heart and kidney damage. The gut microbiota has been linked to HTN, although it is difficult to estimate its significance due to the variety of other features known to influence HTN. In the present study, we used germ-free (GF) and colonized (COL) littermate mice to quantify the impact of microbial colonization on organ damage in HTN. METHODS AND RESULTS: Four-week-old male GF C57BL/6J littermates were randomized to remain GF or receive microbial colonization. HTN was induced by subcutaneous infusion with angiotensin (Ang) II (1.44 mg/kg/d) and 1% NaCl in the drinking water; sham-treated mice served as control. Renal damage was exacerbated in GF mice, whereas cardiac damage was more comparable between COL and GF, suggesting that the kidney is more sensitive to microbial influence. Multivariate analysis revealed a larger effect of HTN in GF mice. Serum metabolomics demonstrated that the colonization status influences circulating metabolites relevant to HTN. Importantly, GF mice were deficient in anti-inflammatory fecal short-chain fatty acids (SCFA). Flow cytometry showed that the microbiome has an impact on the induction of anti-hypertensive myeloid-derived suppressor cells and pro-inflammatory Th17 cells in HTN. In vitro inducibility of Th17 cells was significantly higher for cells isolated from GF than conventionally raised mice. CONCLUSIONS: Microbial colonization status of mice had potent effects on their phenotypic response to a hypertensive stimulus, and the kidney is a highly microbiota-susceptible target organ in HTN. The magnitude of the pathogenic response in GF mice underscores the role of the microbiome in mediating inflammation in HTN. TRANSLATION PERSPECTIVE: To assess the potential of microbiota-targeted interventions to prevent organ damage in hypertension, an accurate quantification of microbial influence is necessary. We provide evidence that the development of hypertensive organ damage is dependent on colonization status and suggest that a healthy microbiota provides anti-hypertensive immune and metabolic signals to the host. In the absence of normal symbiotic host-microbiome interactions, hypertensive damage to the kidney in particular is exacerbated. We suggest that hypertensive patients experiencing perturbations to the microbiota, which are common in CVD, may be at a greater risk for target-organ damage than those with a healthy microbiome.

AimsHypertension (HTN) can lead to heart and kidney damage. The gut microbiota has been linked to HTN, although it is difficult to estimate its significance due to the variety of other features known to influence HTN. In the present study, we used germ-free (GF) and colonized (COL) littermate mice to quantify the impact of microbial colonization on organ damage in HTN.Methods and resultsFour-week-old male GF C57BL/6J littermates were randomized to remain GF or receive microbial colonization. HTN was induced by subcutaneous infusion with angiotensin (Ang) II (1.44mg/kg/d) and 1% NaCl in the drinking water; sham-treated mice served as control. Renal damage was exacerbated in GF mice, whereas cardiac damage was more comparable between COL and GF, suggesting that the kidney is more sensitive to microbial influence. Multivariate analysis revealed a larger effect of HTN in GF mice. Serum metabolomics demonstrated that the colonization status influences circulating metabolites relevant to HTN. Importantly, GF mice were deficient in anti-inflammatory fecal short-chain fatty acids (SCFA). Flow cytometry showed that the microbiome has an impact on the induction of anti-hypertensive myeloid-derived suppressor cells and pro-inflammatory Th17 cells in HTN. In vitro inducibility of Th17 cells was significantly higher for cells isolated from GF than conventionally raised mice.ConclusionsMicrobial colonization status of mice had potent effects on their phenotypic response to a hypertensive stimulus, and the kidney is a highly microbiota-susceptible target organ in HTN. The magnitude of the pathogenic response in GF mice underscores the role of the microbiome in mediating inflammation in HTN.Translation PerspectiveTo assess the potential of microbiota-targeted interventions to prevent organ damage in hypertension, an accurate quantification of microbial influence is necessary. We provide evidence that the development of hypertensive organ damage is dependent on colonization status and suggest that a healthy microbiota provides anti-hypertensive immune and metabolic signals to the host. In the absence of normal symbiotic host-microbiome interactions, hypertensive damage to the kidney in particular is exacerbated. We suggest that hypertensive patients experiencing perturbations to the microbiota, which are common in CVD, may be at a greater risk for target-organ damage than those with a healthy microbiome.

Metabolites produced by the microbiome such as short chain fatty acids (SCFAs) and tryptophan metabolites have been shown to impact the pathogenesis of hypertension. The microenvironment of the host gastrointestinal (GI) tract acts as the site-of-action for many host-microbiome interactions, although this space is not readily accessible. Fecal or serum samples are commonly used as a proxy, relying on the assumption that the obtained information should in some respect represent what is seen at the host epithelial interface. We surmised that it would be feasible to overcome the limitations of such indirect analysis by isolating interstitial fluid (IF) from the gut mucosa. We have established two methodologies to isolate IF from small segments of along GI tract, a centrifugation-based and elution-based approach in rats and mice. For rats and mice, 51 Cr-EDTA tracer experiments were used to demonstrate that fluid obtained was from an extracellular origin and can be reliably considered IF. Using GC-MS, we could identify several SCFAs (acetate, butyrate, propionate, valerate) within eluted IF samples. We were able to empirically measure the enrichment of these metabolites in eluted IF from the colon of rats compared to the duodenum (for propionate; mean difference=59.57 μM, p-value < 0.0001) or the serum (for propionate; mean difference= 60.25 μM, p-value < 0.0001). LC-MS based shotgun proteomics revealed that proteins annotated to the extracellular phase were site-specifically identifiable in IF and were differentially expressed when compared to matched serum samples. Furthermore, we could demonstrate that the use of tissue for IF isolation does not impede the use of other methods such as immunophenotyping or histology. Absolute CD45+ cells from the lamina propria measured using flow cytometry were not influenced by IF methods (p-value = 0.8344) but were unsurprisingly influenced by the gut segment which was analyzed (p-value = 0.0010). The ability to collect IF and directly measure metabolites at the site-of-action overcomes the limitations of indirect analysis of fecal samples or serum from the systemic circulation, and thus offers direct insight into this hitherto underexplored compartment.

Sodium can accumulate in the skin at concentrations exceeding serum levels. A high sodium environment can lead to pathogenic T helper 17 cell expansion. Psoriasis is a chronic inflammatory skin disease in which IL-17. producing T helper 17 cells play a crucial role. In an observational study, we measured skin sodium content in patients with psoriasis and in age-matched healthy controls by Sodium-23 magnetic resonance imaging. Patients with PASI > 5 showed significantly higher sodium and water content in the skin but not in other tissues than those with lower PASI or healthy controls. Skin sodium concentrations measured by Sodium-23 spectroscopy or by atomic absorption spectrometry in ashed-skin biopsies verified the findings with Sodium-23 magnetic resonance imaging. In vitro T helper 17 cell differentiation of naive CD4(+) cells from patients with psoriasis markedly induced IL-17A expression under increased sodium chloride concentrations. The imiquimod-induced psoriasis mouse model replicated the human findings. Extracellular tracer Chromium-51-EDTA measurements in imiquimod- and sham-treated skin showed similar extracellular volumes, rendering excessive water of intracellular origin. Chronic genetic IL-17A-driven psoriasis mouse models underlined the role of IL-17A in dermal sodium accumulation and inflammation. Our data describe skin sodium as a pathophysiological feature of psoriasis, which could open new avenues for its treatment.

The pathogenesis of hypertension is known to involve a diverse range of contributing factors including genetic, environmental, hormonal, hemodynamic and inflammatory forces, to name a few. There is mounting evidence to suggest that the gut microbiome plays an important role in the development and pathogenesis of hypertension. The gastrointestinal tract, which houses the largest compartment of immune cells in the body, represents the intersection of the environment and the host. Accordingly, lifestyle factors shape and are modulated by the microbiome, modifying the risk for hypertensive disease. One well-studied example is the consumption of dietary fibers, which leads to the production of short-chain fatty acids and can contribute to the expansion of anti-inflammatory immune cells, consequently protecting against the progression of hypertension. Dietary interventions such as fasting have also been shown to impact hypertension via the microbiome. Studying the microbiome in hypertensive disease presents a variety of unique challenges to the use of traditional model systems. Integrating microbiome considerations into preclinical research is crucial, and novel strategies to account for reciprocal host-microbiome interactions, such as the wildling mouse model, may provide new opportunities for translation. The intricacies of the role of the microbiome in hypertensive disease is a matter of ongoing research, and there are several technical considerations which should be accounted for moving forward. In this review we provide insights into the host-microbiome interaction and summarize the evidence of its importance in the regulation of blood pressure. Additionally, we provide recommendations for ongoing and future research, such that important insights from the microbiome field at large can be readily integrated in the context of hypertension.

Supplemental Digital Content is available in the text., Background: Dietary high salt (HS) is a leading risk factor for mortality and morbidity. Serum sodium transiently increases postprandially but can also accumulate at sites of inflammation affecting differentiation and function of innate and adaptive immune cells. Here, we focus on how changes in extracellular sodium, mimicking alterations in the circulation and tissues, affect the early metabolic, transcriptional, and functional adaption of human and murine mononuclear phagocytes. Methods: Using Seahorse technology, pulsed stable isotope-resolved metabolomics, and enzyme activity assays, we characterize the central carbon metabolism and mitochondrial function of human and murine mononuclear phagocytes under HS in vitro. HS as well as pharmacological uncoupling of the electron transport chain under normal salt is used to analyze mitochondrial function on immune cell activation and function (as determined by Escherichia coli killing and CD4+ T cell migration capacity). In 2 independent clinical studies, we analyze the effect of a HS diet during 2 weeks (URL: http://www.clinicaltrials.gov. Unique identifier: NCT02509962) and short-term salt challenge by a single meal (URL: http://www.clinicaltrials.gov. Unique identifier: NCT04175249) on mitochondrial function of human monocytes in vivo. Results: Extracellular sodium was taken up into the intracellular compartment, followed by the inhibition of mitochondrial respiration in murine and human macrophages. Mechanistically, HS reduces mitochondrial membrane potential, electron transport chain complex II activity, oxygen consumption, and ATP production independently of the polarization status of macrophages. Subsequently, cell activation is altered with improved bactericidal function in HS-treated M1-like macrophages and diminished CD4+ T cell migration in HS-treated M2-like macrophages. Pharmacological uncoupling of the electron transport chain under normal salt phenocopies HS-induced transcriptional changes and bactericidal function of human and murine mononuclear phagocytes. Clinically, also in vivo, rise in plasma sodium concentration within the physiological range reversibly reduces mitochondrial function in human monocytes. In both a 14-day and single meal HS challenge, healthy volunteers displayed a plasma sodium increase of and respectively, that correlated with decreased monocytic mitochondrial oxygen consumption. Conclusions: Our data identify the disturbance of mitochondrial respiration as the initial step by which HS mechanistically influences immune cell function. Although these functional changes might help to resolve bacterial infections, a shift toward proinflammation could accelerate inflammatory cardiovascular disease.

Sensitive and precise serology assays are needed to measure the humoral response to antigens of respiratory syncytial virus (RSV) following natural infection or vaccination. We developed and evaluated a collection of electrochemiluminescent (ECL) serology assays using four RSV antigens (F, N, Ga and Gb). To assess the merits of ECL technology, the four ECL serology assays were evaluated using a well-characterized "gold standard" panel of acute and convalescent serum samples from fifty-nine RSV-positive and thirty RSV-negative elderly subjects (≥65 years old). The combined results from the four ECL assays demonstrated good concordance to the "gold standard" diagnosis, reaching 95% diagnostic sensitivity and 100% diagnostic specificity. Additionally, a combination of ECL assays provided higher diagnostic sensitivity than a commercially available diagnostic ELISA or cell-based microneutralization assay. In summary, these data demonstrate the advantages of using ECL-based serology assays and highlight their use as a sensitive diagnostic approach to detect recent RSV infection in an elderly population.

SummaryCotransins are cyclic heptadepsipeptides that bind the Sec61 translocon to inhibit cotranslational translocation of a subset of secreted and type I transmembrane proteins. The few known cotransin-sensitive substrates are all targeted to the translocon by a cleavable signal sequence, previously shown to be a critical determinant of cotransin sensitivity. By profiling two cotransin variants against a panel of secreted and transmembrane proteins, we demonstrate that cotransin side-chain differences profoundly affect substrate selectivity. Among the most sensitive substrates we identified is the proinflammatory cytokine tumor necrosis factor alpha (TNF-α). Like all type II transmembrane proteins, TNF-α is targeted to the translocon by its membrane-spanning domain, indicating that a cleavable signal sequence is not strictly required for cotransin sensitivity. Our results thus reveal an unanticipated breadth of translocon substrates whose expression is inhibited by Sec61 modulators.

Der Einsatz mechatronischer Supportsysteme soll den Operateur bei der Durchführung laparoskopischer Eingriffe unterstützen. Als wichtigster Vertreter einer neuen, zweiten Generation der Kameranachführungssysteme ist der SOLOASSIST Gegenstand der vorliegenden Untersuchung. Anhand der Untersuchungskriterien Funktionalität, Zuverlässigkeit, Handhabung, klinischer Einsatz im Modell- und Tierversuch sowie Akzeptanz bei ärztlichem und nicht-ärztlichem Operationspersonal wird der SOLOASSIST auch in Relation zu einem Vertreter der ersten Generation („AESOP“) evaluiert. The use of a mechatronical support system shall facilitate the surgeon during laparoscopic interventions. As the most important representative of a new, second generation camera control system the SOLOASSIST is the object of the present analysis. By the criteria of functionality, realibility, feasibility, clinical application in in and ex vivo experiments as well as acceptance by the medical staff the SOLOASSIST is evaluated also in relation to a representative of a first generation system (AESOP).

To compare the ovarian and endometrial effects of anastrozole and clomiphene when used with gonadotropins in a combination protocol.Prospective randomized trial.Academic infertility center.Fifty infertile women.Women were randomized to receive either 1 mg anastrozole or 100 mg clomiphene citrate for 5 days (cycle days 3-7) followed by FSH injections (days 7-11) for ovulation induction. A subset participated in a crossover arm of the study.Ovarian follicle number and size, E(2) levels, endometrial thickness, pregnancy, and cancellation rates.On cycle day 12, anastrozole cycles were associated with fewer total follicles (1.4 vs. 3.6, P=0.01), fewer mature follicles (0.6 vs. 1.6, P.01), lower serum E(2) (131 pg/mL vs. 613 pg/mL, P.01,) and the same endometrial stripe thickness compared with clomiphene citrate cycles. Cycle cancellation rates were similar between the two groups. On the day of hCG administration in noncancelled cycles, anastrozole cycles were associated with fewer total follicles (1.6 vs. 3.8, P.01), fewer mature follicles (1.3 vs. 2.1, P.01), and an equal endometrial stripe thickness compared with clomiphene citrate cycles. Pregnancy rates were similar between clomiphene (20%) and anastrozole (12%) cycles.Anastrozole when used in conjunction with gonadotropins results in lower E(2) levels and fewer follicles than clomiphene citrate. A combination protocol of anastrozole and gonadotropins may be a safer protocol for patients at higher risk of hyperstimulation and multiple births after infertility treatments.

Objective Polycystic ovary syndrome (PCOS) is associated with biochemical evidence of early atherosclerosis; however, data regarding vascular function are controversial. We hypothesized that resistance vessel function (mediated by the endothelium or smooth muscle) would be impaired in women with PCOS and aimed to determine the contribution of hyperandrogenism, obesity, or insulin resistance to vascular dysfunction. Design Prospective study. Setting University practice. Patient(s) Women with PCOS (n = 24) and age/weight-matched controls (n = 22). Intervention(s) Vascular function was assessed by measuring forearm vasodilatation in response to both endothelium-dependent (acetylcholine/bradykinin) and endothelium-independent dilators (nitroprusside/verapamil). Main Outcome Measure(s) Resistance vessel function. Result(s) Forearm vasodilatation to all four drugs was reduced (>50%) in obese PCOS compared to lean PCOS subjects. There was no significant difference in vascular function between obese or lean women with PCOS compared to corresponding controls. Androgen levels did not correlate with vascular function. Stepwise regression analysis showed that body mass index (BMI) contributed maximally to vascular dysfunction (R2 = 0.47). Conclusion(s) This comprehensive study demonstrates for the first time that obese women with PCOS have markedly reduced vascular smooth muscle function compared to lean subjects with PCOS. In our study obesity and insulin resistance, but not hyperandrogenism, appeared to be significant modulators of vascular function.

The ring-closing metathesis (RCM) of dienynes represents a powerful methodology for the construction of mono- and bicyclic systems containing 1,3-diene functionality. Despite its synthetic potential, the utility of dienyne RCM is significantly reduced due to poor group selectivity. To circumvent this shortcoming, several strategies utilizing steric hindrance, electronic variation, relay metathesis and ring-closure kinetics have been implemented to exert control over the reaction pathways. This article highlights a variety of methods to achieve group-selective enyne RCM of dienynes.

Objective To identify salient variables that influence decision making regarding multifetal reduction (MFR) and describe their effect on individuals over time. Design Prospective, exploratory, descriptive design, using qualitative and quantitative methods. Setting Midwestern tertiary care center. Participants A convenience sample of 11 consecutive consenting couples with triplet or higher-order pregnancies who elected to undergo MFR. Methods Semistructured audiotaped telephone interviews at three points: (a) 2 weeks postreduction, (b) 6 weeks postpartum, and (c) 6 months postpartum; a demographic and marital adjustment questionnaire. Main Outcome Measures Themes identified by content analysis and compared via matrix analysis between males and females and at three points in time; trends in marital adjustment. Results Dominant variables influencing MFR decision making were risks associated with higher-order pregnancies and preservation of infants’ and mothers’ health. Most participants identified emotional issues, including moral and ethical dilemmas, as the most difficult aspect of reduction. Over time, participants reported feeling more positive about their decision; nonetheless, negative feelings emerged progressively. Conclusions Risk aversion favored MFR decision making. Yet, both making and living with the decision were emotionally difficult for this sample. Interventions are needed to assist couples with this decision and its consequences.