Effects of candesartan in hypertensive patients with type 2 diabetes mellitus on inflammatory parameters and their relationship to pulse pressure

Role of C-Reactive Protein, An Inflammatory Biomarker in The Development of Atherosclerosis and Its Treatment

This article deals with the role of c-reactive protein (CRP) in the development of atherosclerosis and its treatment. CRP has a predictive value in ischemic heart disease, restenosis, coronary artery disease, aortic atherosclerosis, and cerebrovascular disease. This article deals with the synthesis and mechanism of CRP-induced atherosclerosis and its treatment. CRP increases the formation of numerous atherogenic biomolecules such as reactive oxygen species (ROS), cytokines (interleukin [IL]-1β and IL-6), cell adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, activated complement C 5 , monocyte colony-stimulating factor, and numerous growth factors [insulin-like growth factor, platelet-derived growth factor, and transforming growth factor-β]). ROS mildly oxidizes low-density lipoprotein (LDL)-cholesterol to form minimally modified LDL which is further oxidized to form oxidized LDL. The above atherogenic biomolecules are involved in the development of atherosclerosis and has been described in detail in the text. This paper also deals with the treatment modalities for CRP-induced atherosclerosis which includes lipid-lowering drugs, antihypertensive drugs, antioxidants, aspirin, antidiabetic drugs, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, regular physical activity, weight reduction, and stoppage of cigarette smoking. In conclusion, CRP induces atherosclerosis through increases in atherogenic biomolecules and the treatment modalities would prevent, regress, and slow the progression of CRP-induced atherosclerosis.

Interventions targeted at oxidatively generated modifications of nucleic acids focused on urine and plasma markers

Oxidative stress is associated with the development and progression of numerous diseases. However, targeting oxidative stress has not been established in the clinical management of any disease. Several methods and markers are available to measure oxidative stress, including direct measurement of free radicals, antioxidants, redox balance, and oxidative modifications of cellular macromolecules. Oxidatively generated nucleic acid modifications have attracted much interest due to the pre-mutagenic oxidative modification of DNA into 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), associated with cancer development. During the last decade, the perception of RNA has changed from that of a 'silent messenger' to an 'active contributor', and, parallelly oxidatively generated RNA modifications measured as 8-oxo-7,8-dihydro-guanosine (8-oxoGuo), has been demonstrated as a prognostic factor for all-caused and cardiovascular related mortality in patients with type 2 diabetes. Several attempts have been made to modify the amount of oxidative nucleic acid modifications. Thus, this review aims to introduce researchers to the measurement of oxidatively generated nucleic acid modifications as well as critically review previous attempts and provide future directions for targeting oxidatively generated nucleic acid modifications.

Potential Protective Role of Blood Pressure-Lowering Drugs on the Balance between Hemostasis and Fibrinolysis in Hypertensive Patients at Rest and During Exercise

In patients with hypertension, the triad represented by endothelial dysfunction, platelet hyperactivity, and altered fibrinolytic function disturbs the equilibrium between hemostasis and fibrinolysis and translates into a hypercoagulable state, which underlies the risk of thrombotic complications. This article reviews the scientific evidence regarding some biological effects of antihypertensive drugs, which can protect patients from the adverse consequences of hypertensive disease, improving endothelial function, enhancing antioxidant activity, and restoring equilibrium between hemostatic and fibrinolytic factors. These protective effects appear not to be mediated through blood pressure reduction and are not shared by all molecules of the same pharmacological class.

Circulating microparticles and central blood pressure according to antihypertensive strategy

OBJECTIVES

This prospective, randomized, open-label study aimed to compare the effects of antihypertensive treatment based on amlodipine or hydrochlorothiazide on the circulating microparticles and central blood pressure values of hypertensive patients.

METHODS

The effects of treatments on circulating microparticles were assessed during monotherapy and after the consecutive addition of valsartan and rosuvastatin followed by the withdrawal of rosuvastatin. Each treatment period lasted for 30 days. Central blood pressure and pulse wave velocity were measured at the end of each period. Endothelial, monocyte, and platelet circulating microparticles were determined by flow cytometry. Central blood pressure values and pulse wave velocity were recorded at the end of each treatment period.

RESULTS

No differences in brachial blood pressure were observed between the treatment groups throughout the study. Although similar central blood pressure values were observed during monotherapy, lower systolic and diastolic central blood pressure values and early and late blood pressure peaks were observed in the amlodipine arm after the addition of valsartan alone or combined with rosuvastatin. Hydrochlorothiazide-based therapy was associated with a lower number of endothelial microparticles throughout the study, whereas a higher number of platelet microparticles was observed after rosuvastatin withdrawal in the amlodipine arm.

CONCLUSIONS

Despite similar brachial blood pressure values between groups throughout the study, exposure to amlodipine was associated with lower central blood pressure values after combination with valsartan, indicating a beneficial interaction. Differences between circulating microparticles were modest and were mainly influenced by rosuvastatin withdrawal in the amlodipine arm.

Efficacy of losartan for improving insulin resistance and vascular remodeling in hemodialysis patients

Insulin resistance and vascular remodeling are prevalent and predict cardiovascular mortality in hemodialysis patients. Angiotensin II (Ang II) may be involved in both pathogenesis. In the present study, we investigated the effects of the Ang II receptor blocker losartan on insulin resistance, arterial stiffness, and carotid artery structure in hemodialysis patients. Seventy-two hemodialysis patients were randomly assigned to receive either losartan 50 mg qd (n = 36) or β-blocker bisoprolol 5 mg qd (n = 36). At the start and at month 12, ambulatory blood pressure (BP) monitoring, aortic pulse wave velocity (PWV) measurements, and carotid artery ultrasound were performed, and homeostasis model assessment index of insulin resistance (HOMA-IR) was determined. During the study period, bioimpedance method was used to evaluate volume status every 3 months. Home-monitored BPs were measured at least monthly. Ambulatory BP decreased significantly and similarly by either losartan or bisoprolol. Decreases in PWVs in losartan group at the end of month 12 were significantly greater than changes in PWV in bisoprolol group (0.9 ± 0.3 vs. 0.4 ± 0.5 m/s, P = 0.021). Common carotid artery intima-media cross-sectional area decreased significantly only in patients treated with losartan (20.3 ± 4.9 vs. 19.1 ± 5.1 mm(2) , P = 0.001), and HOMA-IR was also reduced in losartan group only (1.9 ± 1.0 vs. 1.7 ± 0.8, P = 0.003). Multiple regression analysis showed significant correlations between changes in PWV and changes in HOMA-IR. With comparable BP-lowering efficacy, losartan achieved better improvement in insulin sensitivity, arterial stiffness, and carotid artery hypertrophy in hemodialysis patients. The regression of arterial stiffness may be in part through attenuation in insulin resistance.

Effects of co-administration of candesartan with pioglitazone on inflammatory parameters in hypertensive patients with type 2 diabetes mellitus: a preliminary report

BACKGROUND

Angiotensin receptor blockers (ARBs) are reported to provide direct protection to many organs by controlling inflammation and decreasing oxidant stress. Pioglitazone, an anti-diabetic agent that improves insulin resistance, was also reported to decrease inflammation and protect against atherosclerosis. This study aimed to evaluate the utility of combination therapy with both medicines from the viewpoint of anti-inflammatory effects.

METHODS

We administered candesartan (12 mg daily) and pioglitazone (15 mg daily) simultaneously for 6 months to hypertensive patients with type 2 diabetes mellitus (T2DM) and evaluated whether there were improvements in the serum inflammatory parameters of high-molecular-weight adiponectin (HMW-ADN), plasminogen activator inhibitor-1 (PAI-1), highly sensitive C-reactive protein (Hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), and urinary-8-hydroxydeoxyguanosine (U-8-OHdG). We then analyzed the relationship between the degree of reductions in blood pressure and HbA1c values and improvements in inflammatory factors. Furthermore, we analyzed the relationship between pulse pressure and the degree of lowering of HbA1c and improvements in inflammatory factors. Finally, we examined predictive factors in patients who received benefits from the co-administration of candesartan with pioglitazone from the viewpoint of inflammatory factors.

RESULTS

After 6 months of treatment, in all patients significant improvements from baseline values were observed in HMW-ADN and PAI-1 but not in VCAM-1, Hs-CRP, and U-8-OHdG. Changes in HbA1c were significantly correlated with changes in HMW-ADN and PAI-1 in all patients, but changes in blood pressure were not correlated with any of the parameters examined. Correlation and multilinear regression analyses were performed to determine which factors could best predict changes in HbA1c. Interestingly, we found a significant positive correlation of pulse pressure values at baseline with changes in HbA1c.

CONCLUSIONS

Our data suggest that the pulse pressure value at baseline is a key predictive factor of changes in HbA1c. Co-administration of candesartan with pioglitazone, which have anti-inflammatory (changes in HMW-ADN and PAI-1) effects and protective effects on organs, could be an effective therapeutic strategy for treating hypertensive patients with type 2 diabetes mellitus.

TRIAL REGISTRATION

UMIN-CTR: UMIN000010142.

AT1-receptor-deficiency induced atheroprotection in diabetic mice is partially mediated via PPARγ

Objective

Peroxisome-proliferator–activated-receptor-γ (PPARγ) acts as a transcriptional regulator of multiple genes involved in glucose and lipid metabolism. In vitro studies showed that activated PPARγ suppresses AT1R-gene expression and vice versa. However, it has not yet been determined in vivo, whether AT1R-PPARγ-interactions play a relevant role in the pathogenesis of diabetic complications and specifically in accelerated atherosclerosis.

Methods and results

ApoE^−/− and ApoE^−/−/AT1R^−/−-mice were rendered diabetic by intraperitoneal injections of streptozotocin. Diabetic and non-diabetic ApoE^−/−-mice were further randomized to receive the AT1R antagonist telmisartan, the selective PPARγ antagonist GW9662, telmisartan and GW9662 or vehicle for 18 weeks. Diabetic and non-diabetic ApoE^−/−/AT1R^−/−-mice were randomized to receive either GW9662 or vehicle. GW9662 treatment in diabetic ApoE^−/− and diabetic ApoE^−/−/AT1^−/−-mice resulted in the highest elevation of fasting blood glucose levels, whereas telmisartan treatment and AT1 deficiency in ApoE^−/−-mice showed the lowest fasting blood glucose levels. Diabetic ApoE^−/−-mice displayed severe impairment of endothelial function, enhanced oxidative stress and increased atherosclerotic lesion formation. ApoE^−/−/AT1R^−/− and telmisartan-treated ApoE^−/−-mice showed a significantly better endothelial function, decreased oxidative stress and reduced atherosclerotic lesion formation. Treatment of diabetic ApoE^−/− and ApoE^−/−/AT1R^−/−-mice with the selective PPARγ antagonist GW9662 omitted the atheroprotective effects of AT1R deficiency or AT1 antagonism.

Conclusion

Genetic disruption or pharmacological inhibition of the AT1R attenuates atherosclerosis and improves endothelial function in diabetic ApoE^−/−-mice via the PPARγ pathway.