Kunshen Liu

Potent potentiating diuretic effects of prednisone in congestive heart failure.

Abstract: Animal studies showed glucocorticoids could specifically dilate renal vasculature, regulate synthesis and release of atrial natriuretic peptide (ANP), upregulate ANP receptors on vascular endothelial cells, and thus have potent potentiating diuresis and natriuresis effects in animal studies; however, their diuretic efficacy in humans is yet to be known. Therefore, we designed this randomized, double- blind, placebo-controlled, clinical study to determine the diuretic efficacy of prednisone, a glucocorticoid, in patients with congestive heart failure (CHF). Methods: Twenty clinically stable patients with CHF without overt fluid retention were randomized to a prednisone group or placebo group. Prednisone (1 mg/kg/day with a maximum dose of 60 mg/day) was added to standard care for 7 days, leaving other medications unchanged. Variables included urine volume and electrolytes, serum electrolytes, and change from baseline in serum creatinine. Results: Adding prednisone resulted in striking diuresis and natriuresis with time. As compared with the placebo group, the maximum of mean daily urine volume was 810.5 mL larger than those in the placebo group (95% confidence intervals [CI] 276.25 to 1344.86, P < 0.05). The maximum mean daily sodium excretion was 123.8 mmol higher than those patients given placebo (95% CI 11.4 to 236.2, P < 0.05). The placebo-corrected effect on change from baseline in serum creatinine was −19.5 μmol/L (95% CI −7.4 to −31.6, P < 0.01), favoring prednisone. Conclusions: This pilot study showed that prednisone had potent potentiating diuretic effects in patients with heart failure and might improve renal function in the same time. Further prospective randomized clinical studies are warranted to determine the preferable dose and its efficacy in decompensated congestive heart failure.

Glucocorticoids Improve Renal Responsiveness to Atrial Natriuretic Peptide by Up-Regulating Natriuretic Peptide Receptor-A Expression in the Renal Inner Medullary Collecting Duct in Decompensated Heart Failure

In heart failure, the renal responsiveness to exogenous and endogenous atrial natriuretic peptide (ANP) is blunted. The mechanisms of renal hyporesponsiveness to ANP are complex, but one potential mechanism is decreased expression of natriuretic peptide receptor-A (NPR-A) in inner medullary collecting duct (IMCD) cells. Newly emerging evidence shows that glucocorticoids could produce potent diuresis and natriuresis in patients with heart failure, but the precise mechanism is unclear. In the present study, we found dexamethasone (Dex) dramatically increased the expression of NPR-A in IMCD cells in vitro. The NPR-A overexpression induced by Dex presented in a time- and dose-dependent manner, which emerged after 12 h and peaked after 48 h. The cultured IMCD cells were then stimulated with exogenous rat ANP. Consistent with the findings with NPR-A expression, Dex greatly increased cGMP (the second messenger for the ANP) generation in IMCD cells, which presented in a time- and dose-dependent manner as well. In rats with decompensated heart failure, Dex dramatically increased NPR-A expression in inner renal medulla, which was accompanied by a remarkable increase in renal cGMP generation, urine flow rate, and renal sodium excretion. It is noteworthy that Dex dramatically lowered plasma ANP, cGMP levels, and left ventricular end diastolic pressure. These favorable effects induced by Dex were glucocorticoid receptor (GR)-mediated and abolished by the GR antagonist 17β-hydroxy-11β-[4-dimethylamino phenyl]-17α-[1-propynyl]estra-4,9-dien-3-one (RU486). Collectively, glucocorticoids could improve renal responsiveness to ANP by up-regulating NPR-A expression in the IMCD and induce a potent diuretic action in rats with decompensated heart failure.

Inhibition of Dehydration-Induced Water Intake by Glucocorticoids Is Associated with Activation of Hypothalamic Natriuretic Peptide Receptor-A in Rat

Atrial natriuretic peptide (ANP) provides a potent defense mechanism against volume overload in mammals. Its primary receptor, natriuretic peptide receptor-A (NPR-A), is localized mostly in the kidney, but also is found in hypothalamic areas involved in body fluid volume regulation. Acute glucocorticoid administration produces potent diuresis and natriuresis, possibly by acting in the renal natriuretic peptide system. However, chronic glucocorticoid administration attenuates renal water and sodium excretion. The precise mechanism underlying this paradoxical phenomenon is unclear. We assume that chronic glucocorticoid administration may activate natriuretic peptide system in hypothalamus, and cause volume depletion by inhibiting dehydration-induced water intake. Volume depletion, in turn, compromises renal water excretion. To test this postulation, we determined the effect of dexamethasone on dehydration-induced water intake and assessed the expression of NPR-A in the hypothalamus. The rats were deprived of water for 24 hours to have dehydrated status. Prior to free access to water, the water-deprived rats were pretreated with dexamethasone or vehicle. Urinary volume and water intake were monitored. We found that dexamethasone pretreatment not only produced potent diuresis, but dramatically inhibited the dehydration-induced water intake. Western blotting analysis showed the expression of NPR-A in the hypothalamus was dramatically upregulated by dexamethasone. Consequently, cyclic guanosine monophosphate (the second messenger for the ANP) content in the hypothalamus was remarkably increased. The inhibitory effect of dexamethasone on water intake presented in a time- and dose-dependent manner, which emerged at least after 18-hour dexamethasone pretreatment. This effect was glucocorticoid receptor (GR) mediated and was abolished by GR antagonist RU486. These results indicated a possible physiologic role for glucocorticoids in the hypothalamic control of water intake and revealed that the glucocorticoids can act centrally, as well as peripherally, to assist in the normalization of extracellular fluid volume.

Serum uric acid as an index of impaired renal function in congestive heart failure

Background Hyperuricemia is frequently present in patients with heart failure. Many pathological conditions, such as tissue ischemia, renal function impairment, cardiac function impairment, metabolic syndrome, and inflammatory status, may impact uric acid (UA) metabolism. This study was to assess their potential relations to UA metabolism in heart failure. Methods We retrospectively assessed clinical characteristics, echocardiological, renal, metabolic and inflammatory variables selected on the basis of previous evidence of their involvement in cardiovascular diseases and UA metabolism in a large cohort of randomly selected adults with congestive heart failure (n = 553). By clustering of indices, those variables were explored using factor analysis. Results In factor analysis, serum uric acid (SUA) formed part of a principal cluster of renal functional variables which included serum creatinine (SCr) and blood urea nitrogen (BUN). Univariate correlation coefficients between variables of patients with congestive heart failure showed that the strongest correlations for SUA were with BUN (r = 0.48, P < 0.001) and SCr (r = 0.47, P < 0.001). Conclusions There was an inverse relationship between SUA levels and measures of renal function in patients with congestive heart failure. The strong correlation between SUA and SCr and BUN levels suggests that elevated SUA concentrations reflect an impairment of renal function in heart failure.

Prednisone in Uric Acid Lowering in Symptomatic Heart Failure Patients With Hyperuricemia (PUSH-PATH) Study

BACKGROUND Chronic drug interactions that exist between symptomatic congestive heart failure (CHF) therapy and pharmacologic agents used for hyperuricemia and gout are a challenging problem in clinical practice. Recent observational studies showed that prednisone can induce a potent diuresis and lower serum uric acid concentration (SUA) in CHF. We therefore designed a randomized study to compare the effect of prednisone with allopurinol on SUA in symptomatic CHF patients with hyperuricemia. METHODS Thirty-four symptomatic CHF participants with hyperuricemia (≥ 565 μmol/L) were randomized to receive prednisone (1 mg/kg/d, orally) or allopurinol (100 mg, thrice daily, orally) for 4 weeks. The primary outcome measure was change from baseline in SUA. The secondary outcome measures were change from baseline in serum creatinine levels, estimated glomerular filtration rate, daily urine output, body weight, N-terminal pro-B-type natriuretic peptide levels, physician-assessed global clinical status, and New York Heart Association functional class. RESULTS Both prednisone and allopurinol greatly lowered SUA rapidly. The overall SUA-lowering effect did not differ between treatment groups during the study period (P = 0.48, 2-way repeated measures analysis of variance). However, prednisone increased estimated glomerular filtration rate and daily urine output, and lowered body weights and N-terminal pro-B-type natriuretic peptide. Consequently, participants treated with prednisone had an improvement in clinical status. CONCLUSIONS The study showed that the SUA-lowering effect of prednisone and allopurinol is similar in symptomatic CHF patients. Prednisone might be useful for short-term SUA-lowering in CHF patients with hyperuricemia.

Prednisone in Uric Acid Lowering in Symptomatic Heart Failure Patients with Hyperuricemia — The PUSH-PATH3 Study

Objective. To determine the safety and efficacy of prednisone in patients with symptomatic heart failure (HF) and hyperuricemia. Methods. Prednisone therapy was administered for a short time to 191 symptomatic HF patients with hyperuricemia (serum uric acid > 7 mg/dl). Results. Prednisone significantly reduced serum uric acid by 2.99 mg/dl (p < 0.01) and serum creatinine by 0.17 mg/dl (p < 0.01). These favorable effects were associated with a remarkable increase in urine output, improvement in renal function, and improvement in clinical status. Conclusion. Prednisone can be used safely in symptomatic HF patients with hyperuricemia.

Effect of Corticosteroid on Renal Water and Sodium Excretion in Symptomatic Heart Failure: Prednisone for Renal Function Improvement Evaluation Study.

Background: Recent evidence indicates that prednisone can potentiate renal responsiveness to diuretics in heart failure (HF). However, the optimal dose of prednisone is not known. Method: Thirty-eight patients with symptomatic HF were randomized to receive standard HF care alone (n = 10) or with low-dose (15 mg/d, n = 8), medium-dose (30 mg/d, n = 10), or high-dose prednisone (60 mg/d, n = 10), for 10 days. During this time, we recorded the 24-hour urinary output and the 24-hour urinary sodium excretion, at baseline, on day 5 and day 10. We also monitored the change in the concentration of serum creatinine, angiotensin II, aldosterone, high-sensitive C-reactive protein, tumor necrosis factor-&agr;, interleukin 1&bgr;, and interleukin 6. Results: Low-dose prednisone significantly enhanced urine output. However, the effects of medium- and high-dose prednisone on urine output were less obvious. As for renal sodium excretion, high-dose prednisone induced a more potent natriuresis than low-dose prednisone. Despite the potent diuresis and natriuresis induced by prednisone, serum creatinine, angiotensin II, and aldosterone levels were not elevated. These favorable effects were not associated with an inflammatory suppression by glucocorticoids. Conclusions: Only low-dose prednisone significantly enhanced urine output. However, high-dose prednisone induced a more potent renal sodium excretion than low-dose prednisone.

Relationship between lipids levels and right ventricular volume overload in congestive heart failure

Background The relationship between lipids and coronary artery disease has been well established. However, this is not the case between lipids and heart failure. Ironically, high lipid levels are associated with better outcomes in heart failure, but the mechanisms underlying the phenomenon are not fully understood. This study was performed to test the hypothesis that reduced intestinal lipid absorption due to venous congestion may lead to low lipid levels. Methods We collected data of clinical characteristics, echocardiograph, and lipid profile in 442 unselected patients with congestive heart failure. Correlations between lipid levels [including total cholesterol (TCL), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG)] and right ventricle end diastolic diameter (RVEDD), left ventricle end diastolic diameter (LVEDD), right atrium diameter (RA), left atrium diameter (LA), or left ventricle ejection fraction (LVEF) were analyzed using Pearson correlation and partial correlation. RVEDD, LVEDD, RA, and LA were indexed to the body surface area. Results There was a significantly inverse correlation between TCL levels and RVEDD (r = −0.34, P < 0.001) and RA (r = −0.36, P < 0.001). Other lipids such as LDL-C, HDL-C, and TG had a similar inverse correlation with RVEDD and RA. All these correlations remained unchanged after adjusting for age, gender, smoking status, physical activity levels, comorbidities, and medication use. Conclusions Lipid levels were inversely correlated to RVEDD in patients with congestive heart failure; however, because this was an observational study, further investigation is needed to verify our results as well as identify a causal relationship, if any.

Depression is associated with increased C-reactive protein levels in patients with heart failure and hyperuricemia

Psychological depression is considered a major determinant of health status in patients with heart failure (HF). The incidence of depression in HF is four to five times higher than that in the general population. HF and depression share common pathophysiological features, which include stimulation of the hypothalamus-pituitary-adrenal (HPA) axis and sympathetic activity, and elevated levels of pro-inflammatory cytokines. Over the past decades, growing evidence implicates inflammation activation, as an important pathway, is involved in disease progression in chronic HF. High sensitivity C-reactive protein (hs-CRP), an inflammation cytokine, exerts a detrimental effect on the cardiovascular systems, such as cardiac fibroblasts, myocytes, and vascular cells, by amplifying the inflammatory responsible for adverse ventricular remodeling. Similarly, the link between inflammation and depression also has been well documented over the past two decades. A large amount of evidence shows that subjects with depression have increased level of hs-CRP compared with those without depression. In patients with HF and hyperuricemia, an elevation in uric acid (UA) is associated with impaired renal function and increased increases oxidative stress, resulting in bigger inflammatory burden. However, whether the link between hs-CRP and depression still exists in such population remains unclear. Therefore, we conducted this cross-sectional study to assess the association between hs-CRP and depression patients with HF and hyperuricemia.  The protocol of this cross-sectional study was approved by the institutional ethics committee. This study complied with the Declaration of Helsinki. Inclusion criteria were adult HF patients with New York Heart Association (NYHA) function Class II-IV and systolic dysfunction (left ventricular ejection fraction  45%) and serum uric acid > 7 mg/dL

Prednisone lowers serum uric acid levels in patients with decompensated heart failure by increasing renal uric acid clearance

Clinical studies have shown that large doses of prednisone could lower serum uric acid (SUA) in patients with decompensated heart failure (HF); however, the optimal dose of prednisone and underlying mechanisms are unknown. Thirty-eight patients with decompensated HF were randomized to receive standard HF care alone (n = 10) or with low-dose (15 mg/day, n = 8), medium-dose (30 mg/day, n = 10), or high-dose prednisone (60 mg/day, n = 10), for 10 days. At the end of the study, only high-dose prednisone significantly reduced SUA, whereas low- and medium-dose prednisone and standard HF care had no effect on SUA. The reduction in SUA in high-dose prednisone groups was associated with a significant increase in renal uric acid clearance. In conclusion, prednisone can reduce SUA levels by increasing renal uric acid clearance in patients with decompensated HF.