Lacidipine has antiatherosclerotic effects independent of its actions on lipid metabolism and blood pressure

Lacidipine Attenuates Symptoms of Nicotine Withdrawal in Mice

Nicotine-withdrawal after daily exposure manifests somatic and affective symptom including a range of cognitive deficits. Earlier studies suggested participation of L-type calcium channels (LTCCs) in development of nicotine dependence and expression of withdrawal signs. An upsurge in Ca2+-induced oxidative stress in brain underlies the biochemical events and behavioral signs of nicotine-withdrawal. The present study is aimed to explore the effects of lacidipine (LTCC antagonist) against nicotine-withdrawal. Swiss albino mice were administered ( -)-nicotine hydrogen tartrate (3.35 mg/kg, t.i.d.) from days 1 to 7 and alongside lacidipine (0.3, 1, and 3 mg/kg, i.p.) given from days 1 to 14. Somatic withdrawal signs were noted 48 h after last dose of nicotine. Bay-K8644 (LTCC agonist) was administered in mice subjected to nicotine-withdrawal and lacidipine (3 mg/kg) treatments. Behavioral tests of memory, anxiety, and depression were conducted on days 13 and 14 to assess the effects of lacidipine on affective symptoms of nicotine-withdrawal. Biomarkers of oxido-nitrosative were quantified in the whole brain. Nicotine-withdrawal significantly enhanced somatic signs and symptoms of anxiety, depression, and memory impairment in mice. Lacidipine (1 and 3 mg/kg) attenuated nicotine-withdrawal induced somatic symptoms and also ameliorated behavioral abnormalities. Nicotine-withdrawal triggered an upsurge in brain lipid peroxidation, total nitrite content, and decline in antioxidants, and these effects were attenuated by lacidipine. Bay-K8644 significantly abolished improvement in somatic and affective symptoms, and antioxidant effects by lacidipine in mice subjected to nicotine-withdrawal. Lacidipine mitigated nicotine-withdrawal triggered somatic and affective symptoms owing to decrease in brain oxido-nitrosative stress.

Lacidipine Prevents Scopolamine-Induced Memory Impairment by Reducing Brain Oxido-nitrosative Stress in Mice

Cholinergic deficits and oxido-nitrosative stress are consistently associated with Alzheimer's disease (AD). Previous findings indicate that acetylcholine subdues Ca²⁺ current in the brain. Cholinergic antagonists (e.g., scopolamine) can instigate Ca²⁺-induced redox imbalance, inflammation, and cell-death pathways leading to AD-type memory impairment. Earlier, several Ca²⁺-channel blockers (CCB, e.g., dihydropyridine type) or cholinergic enhancers showed promising results in animal models of AD. In the present research, pretreatment effects of lacidipine (L-type CCB) on learning and memory functions were investigated using the scopolamine mouse model of AD. Swiss albino mice (20-25 g) were administered lacidipine (1 and 3 mg/kg) for 14 days. Scopolamine, an anti-muscarinic drug, was given (1 mg/kg) from days 8 to 14. The mice were subjected to elevated plus maze (EPM) and passive-avoidance (PA) paradigms. Bay-K8644 (a Ca²⁺-channel agonist) was administered before behavioral studies on days 13 and 14. Biochemical parameters of oxidative stress and acetylcholinesterase (AChE) activity were quantified using the whole brain. Behavioral studies showed an increase in transfer latency (TL) in the EPM test and a decrease in step-through latency (STL) in the PA test in scopolamine-administered mice. Scopolamine enhanced the AChE activity and oxidative stress in the brain of mice which resulted in memory impairment. Lacidipine prevented the amnesia against scopolamine and reduced the oxidative stress and AChE activity in the brain of mice. Bay-K8644 attenuated the lacidipine-induced improvement in memory and redox balance in scopolamine-administered mice. Lacidipine can prevent the oxidative stress and improve the cholinergic function in the brain. These properties of lacidipine can mitigate the pathogenesis of AD-type dementia.

Lacidipine attenuates caffeine-induced anxiety-like symptoms in mice: Role of calcium-induced oxido-nitrosative stress

BACKGROUND

Anxiety is a disorder of multi-factorial pathogenesis involving interrelated pathways of neurotransmitters, oxidative stress and metamorphosed calcium-signaling that negatively affects brain functions. Modulation of Ca2+-channels outlines a promising strategy to curb the progression of anxiety-like disorders through attenuation of redox-imbalance. The current research scheme was designed to explore the anxiolytic effects of lacidipine (L-type Ca2+-channel blocker; LCD) pretreatment in caffeine-induced anxiety-like symptom model in mice.

METHODS

Forty-two Swiss albino mice (25-30 g) were distributed to 7 groups (n = 6): Vehicle control, caffeine, alprazolam + caffeine, lacidipine(0.3, 1 and 3 mg/kg, ip)+caffeine and Bay-K8644+LCD(3)+caffeine. Caffeine (25 mg/kg, ip) was administered from day 8 to 14 to induce anxiety-like symptoms in mice. Lacidipine (0.3, 1 and 3 mg/kg, ip) and alprazolam (0.25 mg/kg, ip) were administered from day 1 to 14 in separate groups. Bay-K8644 (Ca2+-channel agonist) was injected on day 14 to delineate the role of Ca2+ in anti-anxiety effect of LCD in caffeine-treated mice. Elevated zero maze and mirror chamber test were employed to assess anxiety-like behavior. Afterwards, the mice were sacrificed and whole brains were harvested for estimation of biomarkers of oxido-nitrosative stress, such as TBARS, GSH, SOD, catalase and total nitrite content.

RESULTS

An increase in brain oxido-nitrosative stress and anxiety-like behavior was observed in caffeine treated mice. LCD pretreatment attenuated the brain oxido-nitrosative stress and anxiety-like behavior in mice in caffeine treated mice. Anxiolytic effect of LCD was attenuated by Bay-K8644 (0.5 mg/kg) in caffeine treated mice.

CONCLUSION

LCD (L-type Ca2+-channel antagonist) pretreatment attenuated caffeine-induced oxido-nitrosative stress and anxiety-like behavior.

Lacidipine attenuates TNF-α-induced cardiomyocyte apoptosis

This study was designed to investigate whether lacidipine elicited a protective role on cardiomyocyte against apoptosis induced by TNF-α. Neonatal rat cardiomyocytes were randomly assigned into different groups. TUNEL staining was utilized to detect apoptosis, and caspase-3 and caspse-12 were determined. To explore the underlying mechanism, Z-ATAD-FMK (a selective caspase-12 inhibitor) was used to identify the key molecule involved. TNF-α increased caspase-3 expression, which was mediated by increased caspase-12 expression. In the meantime, apoptosis was significantly induced by TNF-α. Lacidipine lowered caspase-12 and caspase-3 expression, and cardiomyocyte apoptosis induced by TNF-α. The results suggest that lacidipine attenuates TNF-α -induced apoptosis via inhibition of caspase-12 and caspase-3 successively.

Effects of urotensin II and its specific receptor antagonist urantide on rat vascular smooth muscle cells

We investigated the effects of urantide, a receptor antagonist of urotensin II (U-II), on the expression of U-II and its receptor GPR14 in rat vascular smooth muscle cells. Vascular smooth muscle cells from rat thoracic aorta were cultured by explant method. Subjects in this experiment were divided into eight groups: normal control group (group C), U-II group (group M), positive control group (Flu group) and urantide-treated groups (10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻⁷ and 10⁻⁶ mol/L). Cultured vascular smooth muscle cells in vitro were studied by immunocytochemistry, biochemistry, and flow cytometry. U-II (10⁻⁸ mol/L) promoted the proliferation of vascular smooth muscle cells at each time point, influenced cell cycle, increased proliferation index and S-phase cell fraction, and dramatically promoted the expression of U-II and GPR14. In the concentration range from 10⁻¹⁰ to 10⁻⁶ mol/L, urantide dramatically inhibited the proliferation of vascular smooth muscle cells and the protein expression of U-II and GPR14, especially at a concentration of 10⁻⁶ mol/L. U-II, binding with its receptor GPR14, promotes vascular smooth muscle cells proliferation and migration, which can be inhibited by urantide. This study provides an evidence for understanding the effects of U-II and its receptor GPR14 on vascular smooth muscle cells.

Lacidipine improves endothelial repair capacity of endothelial progenitor cells from patients with essential hypertension

BACKGROUND

Endothelial progenitor cells (EPCs) play a critical role in maintaining the integrity of vascular endothelium following arterial injury. Lacidipine has a beneficial effect on endothelium of hypertensive patients, but limited data are available on EPCs-mediated endothelial protection. This study tests the hypothesis that lacidipine treatment can improve endothelial repair capacity of EPCs from hypertensive patients through increasing CXC chemokine receptor four (CXCR4) signaling.

METHODS

In vivo reendothelialization capacity of EPCs from hypertensive patients with or without in vitro lacidipine treatment was examined in a nude mouse model of carotid artery injury. Expression of CXCR4 and alteration in migration and adhesion functions of EPCs were evaluated.

RESULTS

Basal CXCR4 expression was markedly reduced in EPCs from hypertensive patients compared with normal subjects. In parallel, the phosphorylation of Janus kinase-2 (JAK-2) of EPCs, a CXCR4 downstream signaling, was also significantly decreased. Lacidipine promoted CXCR4/JAK-2 signaling expression of in vitro EPCs. Transplantation of EPCs pretreated with lacidipine significantly accelerated in vivo reendothelialization. The enhanced in vitro function and in vivo reendothelialization capacity of EPCs were inhibited by shRNA-mediated knockdown of CXCR4 expression or pretreatment with JAK-2 inhibitor AG490, respectively. In hypertensive patients, lacidipine treatment for 4 weeks also resulted in an upregulation of CXCR4/JAK-2 signaling of EPCs, which was associated with augmented EPCs-mediated reendothelialization and improved endothelial function.

CONCLUSION

Deterioration of CXCR4 signaling may lead to impaired EPCs-mediated reendothelialization of hypertensive patients. Lacidipine-modified EPCs via a partially CXCR4 signaling contribute to enhanced endothelial repair capacity in hypertension.