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A gastrointestinal–renal kaliuretic signaling axis has been proposed to regulate potassium excretion in response to acute potassium ingestion independent of the extracellular potassium concentration and aldosterone. Here we studied this presumed axis in 32 individuals in our clinical pharmacology unit while on a 20mmol sodium and 60mmol potassium diet. The serum potassium concentration, potassium excretion, aldosterone, and insulin were measured following either a 35mmol oral potassium load, a potassium- and sodium-deficient complex meal, or a potassium-deficient complex meal plus 35mmol potassium. This design allowed determination of the component effects on potassium handling of the meal and potassium load separately. The meal plus potassium test was repeated following aldosterone blockade with eplerenone to specifically evaluate the role of aldosterone. In response to the potassium-deficient meal plus 35mmol potassium, the serum potassium did not increase but the hourly mean potassium excretion increased sharply. This kaliuresis persisted following aldosterone blockade with eplerenone, further suggesting independence from aldosterone. Thus, a gastrointestinal–renal kaliuretic signaling axis exists in humans mediating potassium excretion independent of changes in the serum potassium concentration and aldosterone. The implication of this mechanism is yet to be determined but may account for a significant component of potassium excretion following a complex potassium-rich meal.

A gastrointestinal–renal natriuretic signaling axis has been proposed to regulate sodium excretion in response to acute sodium ingestion. Such an axis is thought to be regulated by a gastrointestinal sodium sensor coupled to the activation/release of a natriuretic signal and could have important clinical and scientific implications. Here we systematically tested for this putative axis and the potential involvement of the gastrointestinal-derived natriuretic prohormones prouroguanylin and proguanylin in 15 healthy volunteers. There was no difference in sodium excretion following equivalent oral or intravenous sodium loads during either high- or low-sodium diets. Furthermore, serum concentrations of prouroguanylin and proguanylin did not increase, did not differ following oral or intravenous sodium, and did not correlate with sodium excretion. Thus, our results do not support an acute gastrointestinal–renal natriuretic axis or a central role for prouroguanylin or proguanylin in humans. If such an axis does exist, it is not characterized by a significant difference in the pattern of sodium excretion following either an oral or intravenous sodium load.

Aldosterone has been implicated in the pathogenesis of progressive cardiovascular disease. Drospirenone (DRSP) is a novel progestin with aldosterone receptor antagonist activity developed for hormone replacement therapy (HRT) as DRSP /17-beta estradiol (DRSP/E2). We investigated the additive effect of DRSP/E2 on 24-hour ambulatory blood pressure in 24 post-menopausal women with mild hypertension treated with enalapril maleate (E). Design: Double-blind, randomized, two parallel group trial. Subjects: 24 non-smoking postmenopausal women receiving E 10 mg bid prior to study were randomized to DRSP/E2 + E (n=12) or placebo (P) + E (n=12) for 14 days . Procedures: 24-hour ambulatory systolic and diastolic blood pressure and serum aldosterone were determined on the day prior to first dose of DRSP/E2 or P (Day -1) and on study Day 14. Both systolic (p=.014) and diastolic (p=.007) mean 24-hour ambulatory blood pressures were decreased from baseline in the DRSP/E2 + E group compared to P + E. No change in systolic or diastolic 24-hour ambulatory blood pressures were observed in the P + E group. Aldosterone increased from baseline by 2.6 (4.5) in the DRSP/E2 + E group, and fell by 0.33 (5.5) in the P + E group (p=0.08). Our results suggest a significant additive blood-pressure lowering effect of DRSP/E2 on both systolic and diastolic blood pressure in hypertensive postmenopausal women receiving E consistent with an antimineralocorticoid effect. In view of the negative results of trials of standard HRT, a HRT with antimineralocorticoid effects could offer a novel potential mechanism for reducing cardiovascular endpoints in postmenopausal women.

Acute ischemic stroke is currently a major cause of disability despite improvement in recanalization therapies. Stem cells represent a promising innovative strategy focused on reduction of neurologic sequelae by enhancement of brain plasticity. We performed a phase IIa, randomized, double-blind, placebo-controlled, single-center, pilot clinical trial. Patients aged ≥60 years with moderate to severe stroke (National Institutes of Health Stroke Scale [NIHSS] 8–20) were randomized (1:1) to receive intravenous adipose tissue–derived mesenchymal stem cells (AD-MSCs) or placebo within the first 2 weeks of stroke onset. The primary outcome was safety, evaluating adverse events (AEs), neurologic and systemic complications, and tumor development. The secondary outcome evaluated treatment efficacy by measuring modified Rankin Scale (mRS), NIHSS, infarct size, and blood biomarkers. We report the final trial results after 24 months of follow-up. Recruitment began in December 2014 and stopped in December 2017 after 19 of 20 planned patients were included. Six patients did not receive study treatment: two due to technical issues and four for acquiring exclusion criteria after randomization. The final study sample was composed of 13 patients (4 receiving AD-MSCs and 9 placebo). One patient in the placebo group died within the first week after study treatment delivery due to sepsis. Two non-treatment-related serious AEs occurred in the AD-MSC group and nine in the placebo group. The total number of AEs and systemic or neurologic complications was similar between the study groups. No injection-related AEs were registered, nor tumor development. At 24 months of follow-up, patients in the AD-MSC group showed a nonsignificantly lower median NIHSS score (interquartile range, 3 [3–5.5] vs 7 [0–8]). Neither treatment group had differences in mRS scores throughout follow-up visits up to month 24. Therefore, intravenous treatment with AD-MSCs within the first 2 weeks from ischemic stroke was safe at 24 months of follow-up.

Obstructive sleep apnea (OSA) is a risk factor for type 2 diabetes that adversely impacts glycemic control. However, there is little evidence about the effect of continuous positive airway pressure (CPAP) on glycemic control in patients with diabetes. To assess the effect of CPAP on glycated hemoglobin (HbA1c) levels in patients with suboptimally controlled type 2 diabetes and OSA, and to identify its determinants. In a 6-month, open-label, parallel, and randomized clinical trial, 50 patients with OSA and type 2 diabetes and two HbA1c levels equal to or exceeding 6.5% were randomized to CPAP (n = 26) or no CPAP (control; n = 24), while their usual medication for diabetes remained unchanged. HbA1c levels, Homeostasis Model Assessment and Qualitative Insulin Sensitivity Check Index scores, systemic biomarkers, and health-related quality of life were measured at 3 and 6 months. After 6 months, the CPAP group achieved a greater decrease in HbA1c levels compared with the control group. Insulin resistance and sensitivity measurements (in noninsulin users) and serum levels of IL-1β, IL-6, and adiponectin also improved in the CPAP group compared with the control group after 6 months. In patients treated with CPAP, mean nocturnal oxygen saturation and baseline IL-1β were independently related to the 6-month change in HbA1c levels (r(2) = 0.510, P = 0.002). Among patients with suboptimally controlled type 2 diabetes and OSA, CPAP treatment for 6 months resulted in improved glycemic control and insulin resistance compared with results for a control group. Clinical trial registered with www.clinicaltrials.gov (NCT01801150).

Postnatal development of the gastrointestinal tract involves the establishment of the commensal microbiota, the acquisition of immune tolerance via a balanced immune cell composition, and maturation of the intestinal epithelium. While studies have uncovered an interplay between the first two, less is known about the role of the maturing epithelium. Here we show that intestinal-epithelial intrinsic expression of lysine-specific demethylase 1A (LSD1) is necessary for the postnatal maturation of intestinal epithelium and maintenance of this developed state during adulthood. Using microbiota-depleted mice, we find plasma cells, innate lymphoid cells (ILCs), and a specific myeloid population to depend on LSD1-controlled epithelial maturation. We propose that LSD1 controls the expression of epithelial-derived chemokines, such as Cxcl16 , and that this is a mode of action for this epithelial-immune cell interplay in local ILC2s but not ILC3s. Together, our findings suggest that the maturing epithelium plays a dominant role in regulating the local immune cell composition, thereby contributing to gut homeostasis. Post birth the gastrointestinal tract undergoes development including the establishment of the microbiome, establishment of tolerance and maturation of the epithelium. Here the authors show a histone demethylase LSD1 is required for postnatal intestinal epithelium maturation and how this impacts local immune cell composition and gut homeostasis.

Background The disease course and long-term outcome of patients with organic acidurias (OAD) and urea cycle disorders (UCD) are incompletely understood. Aims To evaluate the complex clinical phenotype of OAD and UCD patients at different ages. Results Acquired microcephaly and movement disorders were common in OAD and UCD highlighting that the brain is the major organ involved in these diseases. Cardiomyopathy [methylmalonic (MMA) and propionic aciduria (PA)], prolonged QT c interval (PA), optic nerve atrophy [MMA, isovaleric aciduria (IVA)], pancytopenia (PA), and macrocephaly [glutaric aciduria type 1 (GA1)] were exclusively found in OAD patients, whereas hepatic involvement was more frequent in UCD patients, in particular in argininosuccinate lyase (ASL) deficiency. Chronic renal failure was often found in MMA, with highest frequency in mut 0 patients. Unexpectedly, chronic renal failure was also observed in adolescent and adult patients with GA1 and ASL deficiency. It had a similar frequency in patients with or without a movement disorder suggesting different pathophysiology. Thirteen patients (classic OAD: 3, UCD: 10) died during the study interval, ten of them during the initial metabolic crisis in the newborn period. Male patients with late-onset ornithine transcarbamylase deficiency were presumably overrepresented in the study population. Conclusions Neurologic impairment is common in OAD and UCD, whereas the involvement of other organs (heart, liver, kidneys, eyes) follows a disease-specific pattern. The identification of unexpected chronic renal failure in GA1 and ASL deficiency emphasizes the importance of a systematic follow-up in patients with rare diseases.

Abstract Study Objectives: Emerging evidence suggests a role for sleep in contributing to the progression of Alzheimer disease (AD). Slow wave sleep (SWS) is the stage during which synaptic activity is minimal and clearance of neuronal metabolites is high, making it an ideal state to regulate levels of amyloid beta (Aβ). We thus aimed to examine relationships between concentrations of Aβ42 in the cerebrospinal fluid (CSF) and measures of SWS in cognitively normal elderly subjects. Methods: Thirty-six subjects underwent a clinical and cognitive assessment, a structural MRI, a morning to early afternoon lumbar puncture, and nocturnal polysomnography. Correlations and linear regression analyses were used to assess for associations between CSF Aβ42 levels and measures of SWS controlling for potential confounders. Resulting models were compared to each other using ordinary least squared linear regression analysis. Additionally, the participant sample was dichotomized into “high” and “low” Aβ42 groups to compare SWS bout length using survival analyses. Results: A significant inverse correlation was found between CSF Aβ42 levels, SWS duration and other SWS characteristics. Collectively, total SWA in the frontal lead was the best predictor of reduced CSF Aβ42 levels when controlling for age and ApoE status. Total sleep time, time spent in NREM1, NREM2, or REM sleep were not correlated with CSF Aβ42. Conclusions: In cognitively normal elderly, reduced and fragmented SWS is associated with increases in CSF Aβ42, suggesting that disturbed sleep might drive an increase in soluble brain Aβ levels prior to amyloid deposition.

Among patients with recent MI, therapy with a polypill containing aspirin, ramipril, and atorvastatin led to a lower incidence of major adverse cardiovascular events at a median of 3 years than usual care.