Effects of losartan/hydrochlorothiazide on serum uric acid levels and blood pressure in hypertensive patients

Effects of allisartan-isoproxil-based combination antihypertensive regimen in hypertensive patients with microalbuminuria or hyperuricemia

Microalbuminuria and hyperuricemia management are crucial for the integrated management of hypertensive patients. This retrospective post hoc analysis aims to evaluate the optimal allisartan-isoproxil-based combination regimen for hypertensive patients with microalbuminuria or hyperuricemia. A total of 460 hypertensive patients with microalbuminuria and 486 hypertensive patients with hyperuricemia were included in this study. All patients were initially treated with allisartan-isoproxil for 4 weeks. Thereafter, patients with blood pressure (BP) < 140/90 mmHg continued the monotherapy for 8 weeks; patients with BP ≥140/90 mmHg were randomly assigned in a 1:1 ratio to receive allisartan-isoproxil + amlodipine (Group A + C) or allisartan-isoproxil + indapamide (Group A + D) for 8 weeks. The changes of BP, urinary albumin and serum uric acid (UA) were measured. In patients with microalbuminuria, the urinary albumin/creatinine ratio (UACR) significantly decreased by 10.4 mg/g in Group A + C (vs. baseline p = .0035) and 24.2 mg/g in Group A + D (vs baseline p < .0001), intergroup p = NS. In patients with hyperuricemia, serum UA level decreased by 44.5 µmol/L in Group A + C (vs. baseline p = .0003), but increased by 27.2 µmol/L in Group A + D (vs. baseline p = .0167), intergroup p < .0001. The results suggest that for hypertensive patients with microalbuminuria, angiotensin receptor blocker (ARB) + calcium channel blocker (CCB) or ARB+ diuretic both are good choices based on their improvement of microalbuminuria and BP. But for patients with hyperuricemia, ARB + diuretic may further increase the level of UA.

The differential role of uric acid - The purpose or cause of cardiovascular diseases?

For 40 years many studies have been conducted to verify the connection between serum uric acid concentration and cardiovascular diseases, such as myocardial infarction. Unfortunately, it remains unclear which form of uric acid - prooxidant or antioxidant - could be a predictive marker of cardiovascular disease, especially in patients after myocardial infarction. It is well-known that uric acid is an organic compound and the water-soluble final product of purine catabolism, which is catalysed by xanthine oxidoreductase and excreted by kidneys. An increased concentration of UA in human plasma leads to diseases like tumours, renal disorders, atherosclerosis, hypertension, diabetes, metabolic syndrome, polycythaemia vera, haemolytic anaemias, ischemia, oxidative stress, and rare genetic disorders connected with UA degradation. Epidemiological studies have shown that UA might be a marker of oxidative stress, progression of inflammation, or renal disease. A fortiori, it is possible that could also be a predictor for short/long-term survival of patients with CVD. Evidence provided by multiple studies is controversial and mutually exclusive. Among 71 studies the most of them found an independent association between SUA and CVD risk. Some of those studies confirm that CVD risk is higher in women who had elevated SUA levels. On the other hand, many studies reached the opposite conclusion and did not find any relationship between SUA and CVD mortality and morbidity.

Effects of salvianolic acid B and tanshinone IIA on the pharmacokinetics of losartan in rats by regulating the activities and expression of CYP3A4 and CYP2C9

Losartan (LST) is a common chemical drug used to treat high blood pressure and reduce the risk of stroke in certain people with heart disease. Danshen, prepared from the dried root and rhizome of Salvia miltiorrhiza Bunge, has been widely used for prevention and treatment of various cardiovascular and cerebrovascular diseases. There are more than 35 formulations containing Danshen indexed in the 2010 Chinese Pharmacopoeia, which are often combined with LST to treat cardiovascular and cerebrovascular diseases in the clinic. The effects of the two major components of Danshen, salvianolic acid B (SA-B) and tanshinone IIA (Tan IIA), on the pharmacokinetics of losartan and its metabolite, EXP3174, in rats were investigated by liquid chromatography coupled with mass spectrometry (LC-MS). Male Sprague-Dawley rats were randomly assigned to 3 groups: LST, LST+SA-B and LST+Tan IIA, and the main pharmacokinetic parameters were estimated after oral administration of LST, LST+SA-B and LST+Tan IIA. It was found that there are significant differences in the pharmacokinetic parameters among the three groups: Cmax, t1/2, AUC, AUMC in the LST+SA-B group was smaller than those in group LST, while larger in group LST+Tan IIA. Further, the effects of SA-B and Tan IIA on the metabolism of losartan was also investigated using rat liver microsomes in vitro. The results indicated that SA-B can induce the metabolism of LST, while Tan IIA can inhibit the metabolism of LST in rat liver microsomes in vitro by regulating activities of CYP450 enzymes. In addition, the effect of SA-B and Tan IIA on CYP3A4 and CYP2C9 expression was studied in Chang liver cells by western-blotting and Real-time PCR. It was concluded that the two components of Danshen, SA-B and Tan IIA have different influences on the metabolism of LST: SA-B can obviously speed up the metabolism of LST by inducing CYP3A4/CYP2C9 activities and expression, however, Tan IIA can slow down the metabolism of LST by inhibiting CYP3A4/CYP2C9 activities.

Pharmacometabolomic Assessments of Atenolol and Hydrochlorothiazide Treatment Reveal Novel Drug Response Phenotypes

Achieving hypertension (HTN) control and mitigating the adverse health effects associated with HTN continues to be a global challenge. Some individuals respond poorly to current HTN therapies, and mechanisms for response variation remain poorly understood. We used a nontargeted metabolomics approach (gas chromatography time-of-flight/mass spectrometry gas chromatography time-of-flight/mass spectrometry) measuring 489 metabolites to characterize metabolite signatures associated with treatment response to anti-HTN drugs, atenolol (ATEN), and hydrochlorothiazide (HCTZ), in white and black participants with uncomplicated HTN enrolled in the Pharmacogenomic Evaluation of Antihypertensive Responses study. Metabolite profiles were significantly different between races, and metabolite responses associated with home diastolic blood pressure (HDBP) response were identified. Metabolite pathway analyses identified gluconeogenesis, plasmalogen synthesis, and tryptophan metabolism increases in white participants treated with HCTZ (P < 0.05). Furthermore, we developed predictive models from metabolite signatures of HDBP treatment response (P < 1 × 10(-5)). As part of a quantitative systems pharmacology approach, the metabolites identified herein may serve as biomarkers for improving treatment decisions and elucidating mechanisms driving HTN treatment responses.

URAT1 gene polymorphisms influence uricosuric action of losartan in hypertensive patients with hyperuricemia

Aims: To explore the effect of urate transporter 1 (URAT1) polymorphisms on the hypertensive patients with hyperuricemia and the uricosuric action of losartan therapy among hypertensive patients with hyperuricemia. Methods: 101 hypertensive patients with hyperuricemia were detected the genotypes of URAT1 rs1529909 and rs3825016 and undergo a 2-weeks following losartan treatment. Before and after treatment, serum uric acid (SUA) and other clinical data were compared between different genotypes of URAT1 patients. Results: The frequency of rs3825016 (C/T) CT genotype was significant higher in the hypertensive patients with hyperuricemia than that in the healthy controls (32.7 vs 18.8%; p = 0.02). After lorsatan treatment, the patients with the rs3825016 (C/T) or rs1529909 (T/C) mutant genotypes had lower decreased value (DV) of SUA compared with the patients who are wild-type of the variant (p = 0.001 and p < 0.001, respectively). Combined the two variants together, the DV of SUA in two variants both wild-type patients higher than that in the two variants mutant patients (p < 0.0001). Conclusion: These results suggest that URAT1 rs3825016 and rs1529909 polymorphisms influence the uricosuric action of losartan.

Original submitted 20 August 2014; Revision submitted 15 April 2015

Influence of compound danshen tablet on the pharmacokinetics of losartan and its metabolite EXP3174 by liquid chromatography coupled with mass spectrometry

Losartan is an effective anti-hypotension drug frequently used in clinic. Compound danshen tablet (CDST) is an important traditional Chinese multiherbal formula composed of Danshen, Sanqi and Bingpian, which is widely used for the treatment of cardiovascular and cerebrovascular diseases in China. More often, losartan and CDST are simultaneously used for the treatment of anti-hypertension in the clinic. The aim of this study was to compare the pharmacokinetics of losartan and EXP3174 after oral administration of single losartan and both losartan and CDST, and to investigate the influence of CDST on the pharmacokinetics of losartan and its metabolite EXP3174. Male Sprague-Dawley rats were randomly assigned to two groups: a losartan-only group and a losartan and CDST group. Plasma concentrations of losartan and EXP3174 were determined by LC-MS at designated points after drug administration, and the main pharmacokinetic parameters were estimated. It was found that there were significant differences (p < 0.05) between the pharmacokinetic parameters of losartan and EXP3174, which showed that CDST influenced the metabolism and excretion of losartan in vivo. The result could be used for clinical medication guidance of losartan and CDST to avoid the occurrence of adverse reactions.