Comparative effects of different dihydropyridines on the expression of adhesion molecules induced by TNF-alpha on endothelial cells

New Insights into the Nephroprotective Potential of Lercanidipine

Kidneys are responsible for many crucial biological processes in the human body, including maintaining the water-electrolyte balance, pH, and blood pressure (BP), along with the elimination of toxins. Despite this, chronic kidney disease (CKD), which affects more and more people, is a disease that develops insidiously without causing any symptoms at first. The main purpose of this article is to summarize the existing literature on lercanidipine, with a particular focus on its nephroprotective properties. Lercanidipine is a third-generation dihydropyridine (DHP) blocker of calcium channels, and as such it possesses unique qualities such as high lipophilicity and high vascular selectivity. Furthermore, it acts by reversibly inhibiting L-type and T-type calcium channels responsible for exerting positive renal effects. It has been shown to reduce tissue inflammation and tubulointerstitial fibrosis, contributing to a decrease in proteinuria. Moreover, it exhibited antioxidative effects and increased expression of molecules responsible for repairing damaged tissues. It also decreased cell proliferation, preventing thickening of the vascular lumen. This article summarizes studies simultaneously comparing the effect of lercanidipine with other antihypertensive drugs. There is still a lack of studies on the medications used in patients with CKD, and an even greater lack of studies on those used in patients with concomitant hypertension. Therefore, further studies on lercanidipine and its potential in hypertensive patients with coexisting CKD are required.

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.

Lercanidipine in the Management of Hypertension: An Update

Calcium channel blockers (CCBs), particularly dihydropyridine-CCBs, (DHP-CCBs), have an established role in antihypertensive therapy, either as monotherapy or in combination with other antihypertensive drugs. Two hundred and fifty-one papers published in PubMed in English between January 1, 1990, and October 31, 2016, were identified using the keyword "lercanidipine." Lercanidipine is a lipophilic third-generation DHP-CCB, characterized by high vascular selectivity and persistence in the smooth muscle cell membranes. Lercanidipine is devoid of sympathetic activation, and unlike the first and second generation of DHP-CCBs, it dilates both the afferent and the efferent glomerular arteries, while preserving the intraglomerular pressure. In addition, lercanidipine prevents renal damage induced by angiotensin II and demonstrates anti-inflammatory, antioxidant, and anti-atherogenic properties through an increasing bioavailability of endothelial nitric oxide. It is associated with a regression of microvascular structural modifications in hypertensive patients. The efficacy of lercanidipine has been demonstrated in patients with different degrees of hypertension, in the young and elderly and in patients with isolated systolic hypertension. In patients with diabetes and renal impairment, lercanidipine displays a renal protection with a significant decrease of microalbuminuria and improvement of creatinine clearance. Lercanidipine is well tolerated and is associated with a very low rate of adverse events, particularly ankle edema, compared with amlodipine and nifedipine. In conclusion, lercanidipine produces a sustained blood pressure-lowering activity with a high rate of responder/normalized patients, associated with a favorable tolerability profile.

Effects of Administration of Amlodipine and Lacidipine on Inflammation-Induced Bone Loss in the Ovariectomized Rat

This study was performed to evaluate the possible protective effect of two calcium channel blocker's "lacidipine (LAC) and amlodipine (AML)" on bone metabolism in an experimental ovariectomized and inflammation-induced osteoporosis rat model (OVXinf). For the purpose of this study, the rats were divided into eight groups, each containing eight rats: sham-operated control (group 1, SH), sham + inflammation (group 2, SHinf), ovariectomy (group 3, OVX), ovariectomy + inflammation (group 4, OVXinf), ovariectomy + LAC 4 mg/kg (group 5, OVX + LAC), ovariectomy + inflammation + LAC 4 mg/kg (group 6, OVXinf + LAC), ovariectomy + AML 5 mg/kg (group 7, OVX + AML), ovariectomy + inflammation + AML 5 mg/kg (group 8, OVXinf + AML). The levels of osteocalcin and osteopontin decreased in OVXinf + LAC and OVXinf + AML groups. The serum levels of TNF-α, IL-1β, and IL-6 were increased significantly in the OVXinf rats compared with the SH group. Gene expression levels of the osteogenic factor runt-related transcription factor 2 (Runx2) and type I collagen 1A1 (Col1A1) significantly decreased in the OVXinf group, when compared with the control group. AML or LAC administrations increased the levels of Runx2 and Col1A1. These results suggest that amlodipine and lacidipine may be a novel therapeutic target for radical osteoporosis treatment in hypertensive patients.

Efficacy of the combination of amlodipine and candesartan in hypertensive patients with coronary artery disease: a subanalysis of the HIJ-CREATE study

BACKGROUND

The effects of the combination of angiotensin II receptor blocker (ARB) plus dihydropyridine calcium channel blockers (DHP-CCBs), which is known as a potent antihypertensive drug regimen, on cardiovascular events remain unclear.

OBJECTIVE

The purpose of this post hoc subgroup analysis was to compare the incidence of major adverse cardiovascular events (MACE) of patients treated with candesartan and amlodipine with that of those with candesartan and non-amlodipine CCBs in hypertensive patients with coronary artery disease (CAD).

METHODS

HIJ-CREATE was a multicenter, prospective, randomized, controlled study that compared the effects of candesartan-based with those of non-ARB-based standard therapy on MACE in 2049 hypertensive patients with CAD. In the candesartan group, a total of 335 patients were treated with DHP-CCBs (amlodipine: 170 and non-amlodipine-CCBs: 165) at the baseline. In this sub-analysis, we compared, among the participants allocated to candesartan regimen, the long-term effects of amlodipine and non-amlodipine CCBs that were concomitantly given with ARB, although the choice of CCB was not randomized.

RESULTS

The median follow-up was 3.9 years. Treatment using amlodipine with candesartan reduced the risk of MACE by 38% (hazard ratio, 0.62; 95% confidence interval, 0.41-0.94, p=0.025), as compared to patients treated with non-amlodipine-CCBs and candesartan. In a multivariate analysis, combination therapy of candesartan with amlodipine was an independent predictor of reduced risk of MACE.

CONCLUSIONS

The results suggest that the combination of amlodipine and candesartan is more beneficial in reducing MACE in hypertensive patients with CAD compared to non-amlodipine-DHP-CCBs in combination therapy with candesartan. Further investigation in larger-scale prospective randomized studies is required to reach any conclusion as to the superiority of combination therapy of candesartan with amlodipine.

Inhibition of human astrocyte and microglia neurotoxicity by calcium channel blockers

We examined the effects of L-type calcium channel blockers (CCBs) on toxicity exerted by activated human astrocytes and microglia towards SH-SY5Y human neuronal cells. The CCBs nimodipine (NDP) and verapamil (VPM) both significantly suppressed toxic secretions from human astrocytes and astrocytoma U-373 MG cells that were induced by interferon (IFN)-γ. NDP also inhibited neurotoxic secretions of human microglia and monocytic THP-1 cells that were induced by the combination of lipopolysaccharide and IFN-γ. In human astrocytes, both NDP and VPM reduced IFN-γ-induced phosphorylation of signal transducer and activator of transcription (STAT) 3. They also inhibited the astrocytic production of IFN-γ-inducible T cell α chemoattractant (I-TAC). These results suggest that CCBs attenuate IFN-γ-induced neurotoxicity of human astrocytes through inhibition of the STAT3 signaling pathway. L-type CCBs, especially NDP, might be a useful treatment option for a broad spectrum of neurodegenerative diseases, including Alzheimer disease, where the pathology is believed to be exacerbated by neurotoxic glial activation.

Effect of amlodipine + candesartan on cardiovascular events in hypertensive patients with coronary artery disease (from The Heart Institute of Japan Candesartan Randomized Trial for Evaluation in Coronary Artery Disease [HIJ-CREATE] Study)

Combination therapy with calcium channel blockers and angiotensin II receptor blockers is recommended as one of the effective therapies for hypertension. However, it remains unclear whether this combination reduces major adverse cardiovascular events (MACEs) in patients with hypertension with coronary artery disease (CAD). The purpose of the present study was to examine the effects of amlodipine plus candesartan on MACEs in patients with hypertension with CAD. The study population was drawn from The Heart Institute of Japan Candesartan Randomized Trial for Evaluation in Coronary Artery Disease (HIJ-CREATE), which was a multicenter, prospective, randomized controlled trial including 2,049 patients with hypertension with angiographically documented CAD. Subgroup analysis was performed in patients treated with amlodipine at baseline (n = 388). The median follow-up period was 4.3 years. Treatment using amlodipine plus candesartan reduced the risk for MACEs by 39% (p = 0.015) compared to that using amlodipine without angiotensin II receptor blockers. Among the individual events constituting MACEs, the incidence of unstable angina pectoris requiring hospitalization was significantly lower, by 52% (p = 0.007). In conclusion, amlodipine plus candesartan demonstrated a more favorable effect on reducing cardiovascular events in patients with hypertension with CAD compared to amlodipine-based therapy without candesartan.

Amlodipine reduces the antimigratory effect of diclofenac in spontaneously hypertensive rats

Amlodipine, an antihypertensive drug, and diclofenac, an antiinflammatory drug, may generally be combined, particularly in elderly patients; therefore, the potential for their interaction is high. We aim to determine if amlodipine interferes with the antimigratory effect of diclofenac. For this, male spontaneously hypertensive rats (SHRs) were treated with either diclofenac (1 mg.kg.d, 15 d) alone or combined with amlodipine (10 mg.kg.d, 15 d). Leukocyte rolling, adherence, and migration were studied by intravital microscopy. Diclofenac did not change (180.0 +/- 2.3), whereas amlodipine combined (163.4 +/- 5.1) or not (156.3 +/- 4.3) with diclofenac reduced the blood pressure (BP) levels in SHR (183.1 +/- 4.4). Diclofenac and amlodipine reduced leukocyte adherence, migration, and ICAM-1 expression, whereas only diclofenac reduced rolling leukocytes as well. Combined with amlodipine, the effect of the diclofenac was reduced. Neither treatment tested increased the venular shear rate or modified the venular diameters, number of circulating leukocytes, P-selectin, PECAM-1, L-selectin, or CD-18 expressions. No difference could be found in plasma concentrations of both drugs given alone or in association. In conclusion, amlodipine reduces leukocyte migration in SHR, reducing endothelial cell ICAM-1 expression. Amlodipine reduces the effect of the diclofenac, possibly by the same mechanism. A pharmacokinetic interaction as well as an effect on the other adhesion molecules tested could be discarded.

Cilnidipine and Telmisartan Similarly Improves Vascular Damage in Hypertensive Patients

This study was designed to compare the effects of 12-month blood pressure (BP) control using cilnidipine and telmisartan on vascular damage in untreated hypertensive patients. One hundred patients were randomly assigned to either a cilnidipine group or a telmisartan group. The extent of vascular damage was assessed before and after treatment by measuring urinary albumin excretion (UAE), pulse wave velocity (PWV), and intima-media thickness (IMT) of the carotid arteries in each patient. Both drugs similarly decreased BP without altering plasma markers for oxidative stress or inflammation. Both UAE and PWV were significantly improved in both groups, but IMT was significantly reduced only in the cilnidipine group. Multiple regression analyses suggested that the UAE may have decreased as a result of a reduction in intraglomerular pressure caused by telmisartan or by efferent arteriolar dilation caused by cilnidipine. In addition, the PWV may have decreased as a result of the improvement in lipid metabolism caused by telmisartan or the reduction in plasma levels of aldosterone caused by cilnidipine. However, the analyses could not identify any definitive causal relationships or suggest the mechanism responsible for the improvement in IMT caused by cilnidipine. Thus, telmisartan and cilnidipine have unique properties for inhibiting vascular complications.

Amelioration of hypertensive heart failure by amlodipine may occur via antioxidative effects

Although recent clinical studies have suggested that long-acting calcium channel blockers (CCBs) have beneficial effects on heart failure, the precise mechanism is unknown. In this study, Dahl salt-sensitive rats fed a high salt diet were treated with the long-acting CCB amlodipine, the low-molecular-weight membrane permeable superoxide dismutase mimetic 4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl (Tempol), or saline from 11 weeks after birth. The cardiac geometry and function, and gene expression profiles were determined at 17 weeks. Dahl salt-sensitive rats fed a high salt diet followed by saline as a non-treatment control (HS group) showed a marked increase in blood pressure and developed concentric hypertrophy at 11 weeks, followed by left ventricular (LV) dilation and congestive heart failure by 17 weeks. The treatment with amlodipine (AMLO group) or Tempol (TEMP group) significantly inhibited the development of LV hypertrophy and cardiac dysfunction. Analysis using an Affymetrix GeneChip U34 revealed that the expression levels of 195 genes were changed by the treatment with amlodipine. Among these 195 genes, 110 genes were increased in HS rats and decreased in AMLO rats. And of these 110 genes, 54 genes were also decreased in TEMP rats. In contrast, 85 genes were decreased in HS rats and increased in AMLO rats. Of these 85 genes, 38 genes were also increased in TEMP rats. Approximately 48% of the genes were changed in similar fashion in AMLO and TEMP rats, suggesting that amlodipine shows beneficial effects on heart failure mainly via antioxidative mechanisms.

Regression of atherosclerosis by amlodipine via anti-inflammatory and anti-oxidative stress actions

We examined whether amlodipine, an L-type calcium channel blocker (CCB), has an inhibitory effect on oxidative stress and inflammatory response, and thereby atherosclerosis, in apolipoprotein E-deficient (ApoEKO) mice. Adult male ApoEKO mice (6 weeks of age) were fed a high-cholesterol diet (HCD) for 8 or 10 weeks with or without oral administration of amlodipine (3 mg/kg/day) for 10 weeks or for only the last 2 weeks of the HCD. After HCD feeding, atherosclerotic lesion formation, in situ superoxide production and nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase activity were evaluated in the proximal aorta. The expressions of NADPH oxidase subunits (p47(phox) and rac-1), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) were determined with immunohistochemistry and quantitative real-time reverse-transcription polymerase chain reaction. After 8 to 10 weeks of HCD administration to ApoEKO mice, marked atherosclerotic lesion formation was observed in the proximal aorta. In the atherosclerotic lesion, superoxide production, the expression of NADPH oxidase subunits, and NADPH oxidase activity were enhanced, and the expressions of MCP-1, ICAM-1, and VCAM-1 were increased. These changes were suppressed in mice that were treated with amlodipine for 10 weeks concomitant with HCD administration, with no significant change in blood pressure and plasma cholesterol level. We also observed that treatment with amlodipine for only the last 2 weeks regressed the atherosclerotic lesions with a decrease in oxidative stress and vascular inflammation. Inhibition of the atherosclerotic lesion area and lipid area in the proximal aorta by amlodipine was correlated with its inhibitory actions on oxidative stress, inflammation and the production of adhesive molecules. These results suggest that amlodipine not only inhibits atherosclerotic lesion formation, but also regresses atherosclerosis, and that these effects are at least partly due to inhibition of oxidative stress and inflammatory response.

Calcium [corrected] channel blockers reduce angiotensin II-induced superoxide generation and inhibit lectin-like oxidized low-density lipoprotein receptor-1 expression in endothelial cells

Calcium channel blockers have been shown to limit the progression of atherosclerosis and decrease the incidence of cardiovascular events. To investigate vasoprotective effects beyond the blood pressure-lowering effects of these agents, amlodipine (10(-6) mol/) and manidipine (10(-6) mol/l) were used to pretreat angiotensin (Ang) II-stimulated rat cultured aortic endothelial cells. A 3-h period of Ang II treatment enhanced superoxide generation and the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase protein, as detected by dihydroethidium staining and Western blotting, respectively. Pretreatment with amlodipine or manidipine attenuated the increased production of superoxide and the overexpression of NADPH oxidase. The enhanced expression of heme oxygenase-1 (HO-1) mRNA induced by Ang II was further increased by amlodipine, whereas pretreatment with manidipine led to a reduction in the expression of HO-1. Furthermore, Ang II increased vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1), and monocyte chemoattractant protein-1 (MCP-1) mRNA levels, as determined by reverse transcription (RT)-polymerase chain reaction (PCR). Pretreatment with either amlodipine or manidipine decreased the overexpression of VCAM-1, ICAM-1, and MCP-1. We also demonstrated that amlodipine or manidipine prevented the Ang II-induced increase in lectin-like oxidized low-density lipoprotein receptor1 (LOX-1) content, thereby restoring control levels. These observations showed that amlodipine and manidipine reduced superoxide generation by the inhibition of the overexpression of NADPH oxidase in Ang II-stimulated endothelial cells. Such antioxidant effects of these agents might in turn have led to a decrease in the expression of VCAM-1, ICAM-1 and MCP-1. The salutary effects of calcium channel blockers in atherogenesis include the inhibition of the expression of LOX-1.

Cellular and molecular mechanisms of tissue protection by lipophilic calcium channel blockers

Long-acting third-generation dihydropyridine calcium channel blockers (CCBs) improve endothelial dysfunction and prevent cardiovascular events in humans, but their cellular and molecular mechanisms of tissue protection are not elucidated in detail. We assessed organ (renal) protection by the highly lipophilic CCB lercanidipine in a double-transgenic rat (dTGR) model with overexpression of human renin and angiotensinogen genes. We randomly treated dTGR with lercanidipine (2.5 mg/kg/day; n=20) or vehicle (n=20) for 3 wk. Furthermore, we explored the influence of lercanidipine on protein kinase C (PKC) signaling in vivo and in vitro using endothelial and vascular smooth muscle cell cultures. Cumulative mortality was 60% in untreated dTGR, whereas none of the lercanidipine-treated animals died (P<0.001). We found significantly less albuminuria and improved renal function in lercanidipine-treated dTGR (both P<0.05). Lercanidipine treatment also significantly (P<0.05) reduced blood levels of the endogenous NOS inhibitor asymmetric dimethylarginine. On histological examination, we observed significantly less tissue inflammation and fibrosis in lercanidipine-treated animals (both P<0.05). Lercanidipine significantly inhibited angiotensin (ANG) I-mediated PKC-alpha and -delta activation in vivo and in vitro, partly due to reduced intracellular calcium flux. As a result, lercanidipine improved endothelial cell permeability in vitro. Lercanidipine prevents tissue injury and improves survival in a model of progressive organ damage. These effects may result, at least in part, from inhibition of tissue inflammation as well as improved NO bioavailability. Modulation of PKC activity may be an important underlying intracellular mechanism.

Effects of lacidipine on vascular responses in patients with coronary artery disease

BACKGROUND

To evaluate the effects of the calcium channel blocker lacidipine on vascular responses, such as endothelial function and carotid intima-media thickness (IMT), and on levels of high-sensitivity C-reactive protein (hs-CRP) in patients with coronary artery disease (CAD).

METHODS

Endothelial function was assessed by measuring the flow-mediated vasodilation (FMD) of the brachial artery and IMT was measured in the common, bifurcating, and in the internal carotid artery by using high-resolution ultrasound. The study population consisted of 96 consecutive patients [mean age 60 years, male (n) = 70] who showed at least one coronary artery narrowed by more than 50% (coronary angiography). These patients were randomly assigned to lacidipine treatment (4 mg/day, n = 48) or to a placebo (n = 48). We measured FMD, IMT, and hs-CRP prior to and after 6 months of treatment and following coronary angiography in all patients.

RESULTS

Clinical and medical history revealed no significant differences between the groups. IMT of the common carotid artery was significantly diminished from 0.92 +/- 0.15 to 0.87 +/- 0.15 mm 6 months after treatment with lacidipine (p < 0.005). However, IMT of any region in the carotid artery did not show any significant changes in the placebo group. Endothelial function and hs-CRP levels were slightly improved (insignificant) in the lacidipine group. In the placebo group, there were no significant changes.

CONCLUSION

Lacidipine leads to a significant reduction of the common carotid artery IMT as well as to a decrease in markers of inflammation in patients with CAD during a relatively short period (6 months).

Calcium Channel Blockades Exhibit Anti-Inflammatory and Antioxidative Effects by Augmentation of Endothelial Nitric Oxide Synthase and the Inhibition of Angiotensin Converting Enzyme in the NG-Nitro-L-Arginine Methyl Ester-Induced Hypertensive Rat Aorta: Vasoprotective Effects beyond the Blood Pressure-Lowering Effects of Amlodipine and Manidipine

Long-acting dihydropyridine calcium channel blockades have been shown to limit the progression of atherosclerosis and decrease the incidence of cardiovascular events in humans and animals. To investigate the vasoprotective effects beyond the blood pressure-lowering effects of these agents, amlodipine (20 mg/kg/ day) and manidipine (10 mg/kg/day) were administered by gavage to N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats for 2 weeks. L-NAME treatment (0.7 mg/ml in drinking water) significantly decreased the gene and protein expression of endothelial nitric oxide synthase (eNOS) and increased nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, vascular cell adhesion molecule-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1) mRNA levels in the aorta, as determined by Western blotting and reverse transcription (RT)-polymerase chain reaction (PCR). Amlodipine and manidipine normalized the decreased expression of eNOS gene and protein, and attenuated the overexpression of NADPH oxidase, VCAM-1, and MCP-1 mRNA. Furthermore, amlodipine and manidipine prevented the L-NAME-induced increase in the angiotensin converting enzyme (ACE) mRNA content, thereby restoring control levels in the aorta. On the other hand, hydralazine treatment had no such effect in L-NAME treated rats. Furthermore, the increased expression of manganese superoxide dismutase (Mn-SOD) by L-NAME treatment was not affected by amlodipine, manidipine, or hydralazine. We concluded that the direct anti-inflammatory and antioxidative effects of calcium channel blockades in the aorta of rats with L-NAME-induced hypertension were not likely to have been mediated by the blood pressure-lowering action of these agents, but instead these beneficial effects appear to have been mediated by an augmentation of eNOS expression and by the inhibition of the expression of ACE.

Calcium channel blockade and preservation of renal graft function in cyclosporine-treated recipients: a prospective randomized placebo-controlled 2-year study

BACKGROUND

Studies have provided conflicting results as to the protective role of calcium channel blockers (CCB) in cyclosporine-treated patients with regard to blood pressure control and preservation of renal graft function. Lacidipine is a dihydropyridine CCB that possesses antioxidative, anti-atherosclerotic, and anti-adhesion properties and was shown to prevent cyclosporine-induced nephrotoxicity in a rat model.

METHODS

We conducted a multicenter prospective, randomized, placebo-controlled study in 131 de novo recipients of a cadaveric renal allograft on cyclosporine therapy. The aim of this 2-year study was to assess the effects of lacidipine on graft function (plasma iohexol clearance), renal plasma flow, anastomotic arterial blood flow, deterioration of renal function, blood pressure, acute rejection, and hospitalization rate.

RESULTS

A total of 118 recipients were available for intention-to-treat analysis on efficacy (lacidipine: n=59; placebo: n=59). Graft function assessed by serum creatinine concentration and glomerular filtration rate measured as plasma iohexol clearance, was persistently better in lacidipine-treated patients from 1 year onwards (respectively, P<0.01 and P<0.05). Renal plasma flow and anastomotic blood flow were not significantly higher in lacidipine-treated patients. Three patients on lacidipine therapy and four on placebo experienced treatment failure defined as an increase in serum creatinine from baseline of more than 60% (log-rank test: P=0.57). Study groups did not differ in acute rejection rate, trough blood cyclosporine concentrations, blood pressure, number of antihypertensive drugs, hospitalization rate, and adverse event rate.

CONCLUSIONS

The use of calcium channel blockers in cyclosporine-treated renal recipients results in a significantly better allograft function at 2 years and this effect is independent of blood pressure lowering.

Absolute and relative changes in carotid intima???media thickness and atherosclerotic plaques during long-term antihypertensive treatment

BACKGROUND

In ELSA, a randomized, double-blind trial in 2334 hypertensives, 4-year antihypertensive treatment with lacidipine slowed down progression of carotid atherosclerosis significantly more than atenolol treatment. To avoid bias, the primary outcome was measured blindly at study-end on a randomized sequence of scans, but measurements were limited to the four far walls of common carotids and bifurcations (CBMmax) and to one of each couple of duplicate scans recorded yearly.

OBJECTIVES AND METHODS

Secondary outcomes included measurements made on all duplicate scans of both near and far walls, not only of common carotids and bifurcations, but also of internal carotids (12 walls). These measurements were made blindly during the 4-year study, shortly after recording. To avoid possible readers' drift or bias, 250 duplicate baseline scans were re-read at yearly intervals (longitudinal on-line quality control) and a correction factor calculated.

RESULTS

Measurements during the 4-year study showed a trend toward decreased values, with the lacidipine effect significantly greater than the atenolol one. A trend toward lower values was also observed in the longitudinal quality control of baseline scans. After applying a correction factor calculated from this longitudinal control, all measurements no longer decreased with time, but significantly increased, with progression being significantly smaller in lacidipine than in atenolol patients. Corrected values were quite similar to those calculated on measurements carried out at study-end.

CONCLUSION

The relative benefit of lacidipine over atenolol could be measured precisely by reading scans either during the study or at study-end. However, absolute treatment-related changes (progression versus regression) cannot safely be judged by readings made during a long-term study, unless a longitudinal quality control of readings is performed.

Novel anti-inflammatory actions of amlodipine in a rat model of arteriosclerosis induced by long-term inhibition of nitric oxide synthesis

Amlodipine (a new class of calcium channel antagonist) has been shown to limit the progression of arteriosclerosis and decrease the incidence of cardiovascular events. The mechanisms underlying the beneficial effects of amlodipine, however, remain unclear. Therefore, we hypothesized that amlodipine attenuates the development of arteriosclerosis through the inhibition of inflammation in vivo. Long-term inhibition of nitric oxide (NO) by administration of a NO synthase inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME), to rats induces coronary vascular inflammation [monocyte infiltration, monocyte chemoattractant protein-1 (MCP-1) expression, increased activity of angiotensin-converting enzyme (ACE)], and arteriosclerosis. Here, we used the rat model to investigate the anti-inflammatory effects of amlodipine in vivo. Treatment with amlodipine markedly inhibited the L-NAME-induced increase in vascular inflammation, oxidative stress, and local ACE and Rho activity and prevented arteriosclerosis. Interestingly, amlodipine prevented the L-NAME-induced increase in MCP-1 receptor CCR2 expression in circulating monocytes. Amlodipine markedly attenuated the high mortality rate at 8 wk of treatment. These data suggest that amlodipine attenuated arteriosclerosis through inhibiting inflammatory disorders in the rat model of long-term inhibition of NO synthesis. The anti-inflammatory effects of amlodipine seem to be mediated not only by the inhibition of local factors such as MCP-1 but also by the decrease in CCR2 in circulating monocytes. Inhibition of the MCP-1 to CCR2 pathway may represent novel anti-inflammatory actions of amlodipine beyond blood pressure lowering.

Antioxidant activity of different dihydropyridines

Lacidipine, a dihydropyridine-based calcium antagonist (DHP), has already been demonstrated to possess antioxidant activity and to reduce the intracellular production of reactive oxygen species (ROS). To verify if this effect is a peculiarity of this molecule, or belongs to other DHPs, the activity of lacidipine was compared with those of amlodipine, lercanidipine, nimodipine, and nifedipine. The DHPs were incorporated in bovine aortic endothelial cells (BAECs). Cu(2+)-oxidized LDL (ox-LDL, 5 microM) was incubated with BAECs for 5 min. 2',7'-Dichlorofluorescein (DCF) as expression of intracellular ROS production was measured by flow cytometry. Ox-LDL induced a strong increase in intracellular ROS formation (p<0.001) that was significantly reduced only with lacidipine and lercanidipine (p from <0.05 to <0.01); the effect of lacidipine, however, resulted in being much more evident than lercanidipine (p<0.01); amlodipine, nimodopine, and nifedipine had no effect on ROS formation. The lowest IC50s, i.e. the concentrations determining the 50% reduction of ROS, were obtained with lacidipine (p<0.01). The inhibitory effect of lacidipine on ox-LDL-induced ROS production in endothelial cells is a peculiarity of this molecule through its antioxidant activity.

Calcium antagonist lacidipine slows down progression of asymptomatic carotid atherosclerosis: principal results of the European Lacidipine Study on Atherosclerosis (ELSA), a randomized, double-blind, long-term trial

BACKGROUND

Most cardiovascular events associated with hypertension are complications of atherosclerosis. Some antihypertensive agents influence experimental models of atherosclerosis through mechanisms independent of blood pressure lowering.

METHODS AND RESULTS

The European Lacidipine Study on Atherosclerosis (ELSA) was a randomized, double-blind trial in 2334 patients with hypertension that compared the effects of a 4-year treatment based on either lacidipine or atenolol on an index of carotid atherosclerosis, the mean of the maximum intima-media thicknesses (IMT) in far walls of common carotids and bifurcations (CBM(max)). This index has been shown by epidemiological studies to be predictive of cardiovascular events. A significant (P<0.0001) effect of lacidipine was found compared with atenolol, with a treatment difference in 4-year CBM(max) progression of -0.0227 mm (intention-to-treat population) and -0.0281 mm (completers). The yearly IMT progression rate was 0.0145 mm/y in atenolol-treated and 0.0087 mm/y in lacidipine-treated patients (completers, 40% reduction; P=0.0073). Patients with plaque progression were significantly less common, and patients with plaque regression were significantly more common in the lacidipine group. Clinic blood pressure reductions were identical with both treatments, but 24-hour ambulatory systolic/diastolic blood pressure changes were greater with atenolol (-10/-9 mm Hg) than with lacidipine (-7/-5 mm Hg). No significant difference between treatments was found in any cardiovascular events, although the relative risk for stroke, major cardiovascular events, and mortality showed a trend favoring lacidipine.

CONCLUSION

The greater efficacy of lacidipine on carotid IMT progression and number of plaques per patient, despite a smaller ambulatory blood pressure reduction, indicates an antiatherosclerotic action of lacidipine independent of its antihypertensive action.

HIV-1 envelope glycoprotein 120 increases intercellular adhesion molecule-1 expression by human endothelial cells

Human immunodeficiency virus type 1 (HIV-1) infection is often associated with central nervous system damage and vascular complications. However, the mechanisms of this association are largely unknown. We examined the effect of HIV-1 envelope glycoprotein 120 (gp120) on cell adhesion molecule expression by endothelial cells. We found, for the first time, that both soluble and membrane-bound gp120 could significantly increase the expression of human endothelial intercellular adhesion molecule-1 (ICAM-1) at both mRNA and protein levels, but not vascular cell adhesion molecule-1 and E-selectin. The specificity of gp120-mediated response was demonstrated by blocking experiments using a specific monoclonal antibody against gp120, which successfully abolished the gp120-mediated increase of ICAM-1 expression. Furthermore, there was a significant increase of human monocytic cell line THP-1 adherence onto the gp120-treated endothelial monolayers. This increased cell adhesion was effectively blocked by either anti-gp120 or anti-ICAM antibodies. These findings suggest that HIV-1 gp120-mediated endothelial ICAM-1 expression could be one of the important mechanisms of HIV-1 pathogenesis.

Lacidipine inhibits adhesion molecule and oxidase expression independent of blood pressure reduction in angiotensin-induced vascular injury

Dihydropyridines can inhibit gene expression in-vitro and may have a protective vascular effect independent of blood pressure reduction. We tested the hypothesis that lacidipine prevents induction of inducible NO synthase (iNOS), influences leukocyte adhesion and infiltration, inhibits nuclear factor (NF)-kappaB transcription factor activity, and ameliorates end-organ damage in a transgenic rat model of angiotensin (Ang) II--dependent organ sclerosis. We treated rats transgenic for human renin and angiotensinogen (dTGR) from week 4 to 7 with lacidipine (0.3 or 3 mg/kg by gavage). Blood pressure was measured by tail cuff. Organ damage was assessed by histology and immunohistochemistry. Adhesion molecules and cytokines were analyzed by immunohistochemistry. Transcription factors were analyzed by mobility shift assays. Untreated dTGR developed moderate hypertension, cardiac hypertrophy, and severe renal damage with albuminuria. Lacidipine decreased blood pressure slightly at the low dose and substantially at the higher dose. However, both treatments reduced albuminuria and plasma creatinine to the same degree (P<0.05). Intercellular adhesion molecule-1 (ICAM-1) was markedly reduced by lacidipine as well as renal neutrophil and monocyte infiltration. Lacidipine reduced mitogen-activated protein (MAP) kinase phosphorylation and iNOS expression in both cortex and medulla. NF-kappaB and AP-1 were activated in dTGR but reduced by lacidipine. Lacidipine ameliorates Ang II-induced end-organ damage independent of blood pressure lowering, perhaps by inhibiting the MAP kinase pathway and NF-kappaB activation.

Amlodipine increases nitric oxide synthesis in cytokine-stimulated cultured vascualar smooth muscle cells

OBJECTIVE

If calcium channel blockers affect nitric oxide synthesis in the vascular tissue, they could influence disease progression in coronary arteries. We investigated the effects of the calcium channel blocker amlodipine on nitric oxide synthesis by measuring the production of nitrite, a stable metabolite of nitric oxide, in vascular smooth muscle cells.

METHODS

We measured the production of nitrate in cultured rat vascular smooth muscle cells with the Griess reagent Inducible nitric oxide synthase protein and mRNA expression were assayed by Western blotting and reverse transcription-polymerase chain reaction, respectively. The levels of NF-kappaB proteins in nuclear extracts were analyzed by gel retardation assay.

RESULTS

Incubation of cultures with interleukin-1 , (10 ng/ ml) for 24 h caused a significant increase in nitrite generation. Interleukin-1 l-induced nitrite production by vascular smooth muscle cells was significantly increased by amlodipine in a dose-dependent manner. This augmentative effect of amlodipine was completely abolished in the presence of N(G)-monomethyl-L-arginine or actinomycin D. Amlodipine-induced nitrite production was accompanied by increased inducible nitric oxide synthase mRNA and protein accumulation. Interleukin-1 , induced NF-kappaB activation in vascular smooth muscle cells, and addition of amlodipine further increased this NF-kappaB activation. The effect of amlodipine on nitrite production was maintained in the presence of the calcium channel agonist Bay K 8644.

CONCLUSION

Amlodipine enhances nitric oxide synthesis in cytokine-stimulated cultured vascular smooth muscle cells by L-type calcium channel-independent mechanisms.