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1.
Neuropharmacology ; : 110059, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38992791

ABSTRACT

Stimulation of the dorsal half of the rat periaqueductal gray (DPAG) with 60-Hz pulses of increasing intensity, 30-µA pulses of increasing frequency, or increasing doses of an excitatory amino acid elicits sequential defensive responses of exophthalmia, immobility, trotting, galloping, and jumping. These responses may be controlled by voltage-gated calcium channel-specific firing patterns. Indeed, a previous study showed that microinjection of the DPAG with 15 nmol of verapamil, a putative blocker of L-type calcium channels, attenuated all defensive responses to electrical stimulation at the same site as the injection. Accordingly, here we investigated the effects of microinjection of lower doses (0.7 and 7 nmol) of both verapamil and mibefradil, a preferential blocker of T-type calcium channels, on DPAG-evoked defensive behaviors of the male rat. Behaviors were recorded either 24 h before or 10 min, 24 h, and 48 h after microinjection. Effects were analyzed by both threshold logistic analysis and repeated measures analysis of variance for treatment by session interactions. Data showed that the electrodes were all located within the dorsolateral PAG. Compared to the effects of saline, verapamil significantly attenuated exophthalmia, immobility, and trotting. Mibefradil significantly attenuated exophthalmia and marginally attenuated immobility while facilitating trotting. While galloping was not attenuated by either antagonist, jumping was unexpectedly attenuated by 0.7 nmol verapamil only. These results suggest that T-type calcium channels are involved in the low-threshold freezing responses of exophthalmia and immobility, whereas L-type calcium channels are involved in the trotting response that precedes the full-fledged escape responses of galloping and jumping.

2.
Int J Biol Macromol ; : 133742, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38986998

ABSTRACT

This study aims to investigate the molecular mechanisms and the neuroprotective effect of hyaluronic acid modified verapamil-loaded carbon quantum dots (VRH-loaded HA-CQDs) against an in-vitro Alzheimer's disease model induced by amyloid beta (Aß) in SH-SY5Y and Neuro 2a neuroblastoma cells. Briefly, different HA-CQDs were prepared using hydrothermal method and optimized by Box-Behnken design to maximize quantum yield and minimize particle size. Serum stable negatively charged VRH-loaded HA-CQDs was successfully prepared by admixing the optimized HA-CQDs and VRH with association efficiency and loading capacity of 81.25 ±â€¯3.65 % and 5.11 ±â€¯0.81 %, respectively. Cells were pretreated with VRH solution or loaded-HA-CQDs followed by exposure to Aß. Compared to the control group, amyloidosis led to reduction in cellular proliferation, mitochondrial membrane potential, expression of cytochrome P450, cytochrome c oxidase, CREB-regulated transcriptional coactivator 3, and mitotic index, along with marked increase in reactive oxygen species (ROS) and inflammatory cytokines. Pretreatment with VRH, either free or loaded HA-CQDs, enhanced cell survival, mitochondrial membrane potential, mitotic index, and gene expression. It also reduced inflammation and ROS. However, VRH-loaded HA-CQDs exhibited superior effectiveness in the measured parameters. These findings suggest that VRH-loaded HA-CQDs have enhanced therapeutic potential compared to free VRH in mitigating amyloidosis negative features.

3.
J Clin Transl Endocrinol ; 36: 100352, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38860154

ABSTRACT

Objectives: To report the safety and side effects associated with taking verapamil for beta-cell preservation in children with newly-diagnosed T1D. Research Design and Methods: Eighty-eight participants aged 8.5 to 17.9 years weighing ≥ 30 kg were randomly assigned to verapamil (N = 47) or placebo (N = 41) within 31 days of T1D diagnosis and followed for 12 months from diagnosis, main CLVer study. Drug dosing was weight-based with incremental increases to full dosage. Side effect monitoring included serial measurements of pulse, blood pressure, liver enzymes, and electrocardiograms (ECGs). At study end, participants were enrolled in an observational extension study (CLVerEx), which is ongoing. No study drug is provided during the extension, but participants may use verapamil if prescribed by their diabetes care team. Results: Overall rates of adverse events were low and comparable between verapamil and placebo groups. There was no difference in the frequency of liver function abnormalities. Three CLVer participants reduced or discontinued medication due to asymptomatic ECG changes. One CLVerEx participant (18 years old), treated with placebo during CLVer, who had not had a monitoring ECG, experienced complete AV block with a severe hypotensive episode 6 weeks after reaching his maximum verapamil dose following an inadvertent double dose on the day of the event. Conclusions: The use of verapamil in youth newly-diagnosed with T1D appears generally safe and well tolerated with appropriate monitoring. We strongly recommend monitoring for potential side effects including an ECG at screening and an additional ECG once full dosage is reached.ClinicalTrials.gov number: NCT04233034.

4.
Int J Cardiol ; 410: 132228, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38844092

ABSTRACT

BACKGROUND: no-reflow can complicate up to 25% of pPCI and is associated with significant morbidity and mortality. We aimed to compare the outcomes of intracoronary epinephrine and verapamil with intracoronary adenosine in the treatment of no-reflow after primary percutaneous coronary intervention (pPCI). METHODS: 108 STEMI patients had no-reflow during pPCI were assigned into four groups. Group 1, in which epinephrine and verapamil were injected through a well-cannulated guiding catheter. Group 2, in which same drugs were injected in the distal coronary bed through a microcatheter or perfusion catheter. Group 3, in which adenosine was injected through a guiding catheter. Group 4, in which adenosine was injected in distal coronary bed. Primary end point was the achievement of TIMI III flow and MBG II or III. Secondary end point was major adverse cardiovascular and cerebrovascular events (MACCEs) during hospital stay. RESULTS: The study groups did not differ in their baseline characteristics. Primary end point was achieved in 15 (27.8%) patients in the guide-delivery arm compared with 34 (63%) patients in the local-delivery arm, p < 0.01. However, the primary end point did not differ between the epinephrine/verapamil group and the adenosine group (27 (50%) vs 22 (40.7%), p = 0.334). The secondary end points were similar between the study groups. CONCLUSION: Local delivery of epinephrine, verapamil and adenosine in the distal coronary bed is more effective in achieving TIMI III flow with MBG II or III compared with their guide-delivery in patients who suffered no-reflow during pPCI. There was no difference between epinephrine/verapamil Vs. adenosine.


Subject(s)
Adenosine , Epinephrine , No-Reflow Phenomenon , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Verapamil , Humans , Verapamil/administration & dosage , Male , Female , Adenosine/administration & dosage , Epinephrine/administration & dosage , Middle Aged , Percutaneous Coronary Intervention/methods , No-Reflow Phenomenon/etiology , No-Reflow Phenomenon/drug therapy , ST Elevation Myocardial Infarction/drug therapy , ST Elevation Myocardial Infarction/therapy , ST Elevation Myocardial Infarction/surgery , Aged , Vasodilator Agents/administration & dosage , Treatment Outcome , Prospective Studies
5.
Cells ; 13(11)2024 May 30.
Article in English | MEDLINE | ID: mdl-38891081

ABSTRACT

This study unveils verapamil's compelling cytoprotective and proliferative effects on pancreatic ß-cells amidst diabetic stressors, spotlighting its unforeseen role in augmenting cholecystokinin (CCK) expression. Through rigorous investigations employing MIN6 ß-cells and zebrafish models under type 1 and type 2 diabetic conditions, we demonstrate verapamil's capacity to significantly boost ß-cell proliferation, enhance glucose-stimulated insulin secretion, and fortify cellular resilience. A pivotal revelation of our research is verapamil's induction of CCK, a peptide hormone known for its role in nutrient digestion and insulin secretion, which signifies a novel pathway through which verapamil exerts its therapeutic effects. Furthermore, our mechanistic insights reveal that verapamil orchestrates a broad spectrum of gene and protein expressions pivotal for ß-cell survival and adaptation to immune-metabolic challenges. In vivo validation in a zebrafish larvae model confirms verapamil's efficacy in fostering ß-cell recovery post-metronidazole infliction. Collectively, our findings advocate for verapamil's reevaluation as a multifaceted agent in diabetes therapy, highlighting its novel function in CCK upregulation alongside enhancing ß-cell proliferation, glucose sensing, and oxidative respiration. This research enriches the therapeutic landscape, proposing verapamil not only as a cytoprotector but also as a promoter of ß-cell regeneration, thereby offering fresh avenues for diabetes management strategies aimed at preserving and augmenting ß-cell functionality.


Subject(s)
Cell Proliferation , Cholecystokinin , Insulin-Secreting Cells , Verapamil , Zebrafish , Animals , Verapamil/pharmacology , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/drug effects , Cholecystokinin/metabolism , Cholecystokinin/pharmacology , Cell Proliferation/drug effects , Regeneration/drug effects , Cell Line , Mice , Disease Models, Animal , Insulin/metabolism , Glucose/metabolism
6.
EBioMedicine ; 105: 105206, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38901147

ABSTRACT

BACKGROUND: Cerebral vasospasm (CV) is a feared complication which occurs after 20-40% of subarachnoid haemorrhage (SAH). It is standard practice to admit patients with SAH to intensive care for an extended period of resource-intensive monitoring. We used machine learning to predict CV requiring verapamil (CVRV) in the largest and only multi-center study to date. METHODS: Patients with SAH admitted to UCLA from 2013 to 2022 and a validation cohort from VUMC from 2018 to 2023 were included. For each patient, 172 unique intensive care unit (ICU) variables were extracted through the primary endpoint, namely first verapamil administration or no verapamil. At each institution, a light gradient boosting machine (LightGBM) was trained using five-fold cross validation to predict the primary endpoint at various hospitalization timepoints. FINDINGS: A total of 1750 patients were included from UCLA, 125 receiving verapamil. LightGBM achieved an area under the ROC (AUC) of 0.88 > 1 week in advance and ruled out 8% of non-verapamil patients with zero false negatives. Our models predicted "no CVRV" vs "CVRV within three days" vs "CVRV after three days" with AUCs = 0.88, 0.83, and 0.88, respectively. From VUMC, 1654 patients were included, 75 receiving verapamil. VUMC predictions averaged within 0.01 AUC points of UCLA predictions. INTERPRETATION: We present an accurate and early predictor of CVRV using machine learning with multi-center validation. This represents a significant step towards optimized clinical management and resource allocation in patients with SAH. FUNDING: Robert E. Freundlich is supported by National Center for Advancing Translational Sciences federal grant UL1TR002243 and National Heart, Lung, and Blood Institute federal grant K23HL148640; these funders did not play any role in this study. The National Institutes of Health supports Vanderbilt University Medical Center which indirectly supported these research efforts. Neither this study nor any other authors personally received financial support for the research presented in this manuscript. No support from pharmaceutical companies was received.

7.
Life Sci ; 352: 122877, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38942358

ABSTRACT

AIMS: The study evaluated the antiviral effect of Verapamil against respiratory syncytial virus (RSV) and investigated its underlying mechanism. MATERIALS AND METHODS: RSV-infected BALB/c mice were treated with Verapamil. Body weight, survival rates, viral load, lung damage, inflammatory factors, and the expression of RSV fusion (F) protein were analyzed. In cellular studies, intracellular Ca2+ and viral titers were measured in the presence of Verapamil, Calcium Chloride, and EGTA. A time-of-addition assay assessed the antiviral effect of Verapamil. KEY FINDINGS: Mice infected with RSV and treated with Verapamil exhibited a significant decrease in weight loss, an increase in survival rates, and reductions in viral titers, RSV F protein expression, inflammatory responses, and lung tissue injury. Verapamil reduced intracellular calcium levels, which correlated with reduced viral titers. The addition of calcium chloride reversed the anti-viral effects mediated by Verapamil, while EGTA potentiated them. The antiviral activity of Verapamil was observed during the early phase of RSV infection, likely by blocking Ca2+ channels and inhibiting virus replication. SIGNIFICANCE: Verapamil effectively inhibits RSV infection by blocking calcium channels and reducing intracellular calcium levels, thereby impeding viral replication. Thus, Verapamil shows promise as a treatment for RSV.

8.
Int J Antimicrob Agents ; 64(2): 107233, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38824971

ABSTRACT

Acinetobacter baumannii, which is predominantly responsible for hospital-acquired infections, presents a tremendous clinical challenge due to its increasing antibiotic resistance to colistin (COL), a last-line antibiotic. As a result, the combination of antimicrobial and non-antimicrobial agents is emerging as a more popular treatment approach against infections caused by COL-resistant A. baumannii. This study administered COL and verapamil (VER), that is an antihypertensive and antiarrhythmic agent. We found that the susceptibility of A. baumannii to COL was restored both in vitro and in vivo. Scanning electron microscope and Crystal violet staining showed inhibition of the VER/COL combination on bacterial biofilm formation. Cytotoxicity assay and haemolysis test were used to confirm in vitro safety evaluation. Further experiments using propidium iodide staining revealed that the VER/COL combination improved the therapeutic efficacy of COL by modifying the permeability of bacterial membranes. As demonstrated by reactive oxygen species experiments, the drug combination caused the accumulation of bacterial reactive oxygen species and their eventual death. Additionally, VER/COL treatment significantly reduced the efflux of Rhodamine 123 (Rh123). For the first time, this study identifies the anti-hypertensive drug VER as a COL potentiator against A. baumannii, providing a potential treatment approach against A. baumannii infections and improving patient outcomes.

9.
Heart Rhythm ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38909715

ABSTRACT

BACKGROUND: Direct oral anticoagulants (DOACs) are commonly co-prescribed with amiodarone/diltiazem/verapamil, but whether there is a drug interaction between these drugs is unclear. OBJECTIVE: To investigate the risk of clinical outcomes associated with concomitant use of DOACs and amiodarone/diltiazem/verapamil. METHODS: We identified DOAC users in the Clinical Practice Research Datalink Aurum from 1/1/2011-31/12/2019. We used a cohort design to estimate hazard ratios for Ischaemic stroke, myocardial infarction, venous thromboembolism, intracranial bleeding, gastrointestinal bleeding, other bleeding, cardiovascular mortality, and all-cause mortality comparing DOACs+amiodarone/diltiazem/verapamil users, respectively and DOACs+beta-blocker users. A case-crossover design comparing odds of exposure to different drug initiation patterns for all outcomes in hazard window versus referent window within an individual was also conducted. RESULTS: Of 397,459 DOAC users, we included 9075 co-prescribed amiodarone, 9612 co-prescribed diltiazem, and 2907 co-prescribed verapamil. There was no difference in risk of any outcomes between DOACs+amiodarone/diltiazem/verapamil users, respectively versus DOACs+beta-blocker users in cohort design. However, in case-crossover design, we observed an odds ratio (OR) of 2.09 (99%CI: 1.37-3.18) for all-cause mortality associated with an initiation of a DOAC while taking amiodarone; which was greater than that observed for DOAC monotherapy (OR: 1.30; 99%CI: 1.25-1.35). Similar findings were observed for cardiovascular mortality and all-cause mortality respectively with diltiazem. CONCLUSIONS: Our study shows no evidence of higher bleeding or cardiovascular risk associated with co-prescribed DOACs and amiodarone, diltiazem or verapamil respectively. The elevated risks of cardiovascular and all-cause mortality were only observed during DOAC initiation when diltiazem/amiodarone were being taken.

12.
Int Immunopharmacol ; 133: 112153, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38678669

ABSTRACT

LPS induced sepsis is a complex process involving various immune cells and signaling molecules. Dysregulation of macrophage polarization and ROS production contributed to the pathogenesis of sepsis. PGP is a transmembrane transporter responsible for the efflux of a number of drugs and also expressed in murine macrophages. Natural products have been shown to decrease inflammation and expression of efflux transporters. However, no treatment is currently available to treat LPS induced sepsis. Verapamil and Tangeretin also reported to attenuate lipopolysaccharide-induced inflammation. However, the effects of verapamil or tangeretin on lipopolysaccharide (LPS)-induced sepsis and its detailed anti-inflammatory mechanism have not been reported. Here, we have determined that verapamil and tangeretin protects against LPS-induced sepsis by suppressing M1 macrophages populations and also through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression in macrophages. An hour before LPS (10 mg/kg) was administered; mice were given intraperitoneal injections of either verapamil (5 mg/kg) or tangeretin (5 mg/kg). The peritoneal macrophages from different experimental groups of mice were isolated. Hepatic, pulmonary and splenic morphometric analyses revealed that verapamil and tangeretin decreased the infiltration of neutrophils into the tissues. Verapamil and tangeritin also enhanced the activity of SOD, CAT, GRX and GSH level in all the tissues tested. verapamil or tangeretin pre-treated mice shifted M1 macrophages to M2 type possibly through the inhibition of P-glycoprotein expression via downregulating STAT1/STAT3 and upregulating SOCS3 expression. Hence, both these drugs have shown protective effects in sepsis via suppressing iNOS, COX-2, oxidative stress and NF-κB signaling in macrophages. Therefore, in our study we can summarize that mice were treated with either Vera or Tan before LPS administration cause an elevated IL-10 by the macrophages which enhances the SOCS3 expression, and thereby able to limits STAT1/STAT3 inter-conversion in the macrophages. As a result, NF-κB activity is also getting down regulated and ultimately mitigating the adverse effect of inflammation caused by LPS in resident macrophages. Whether verapamil or tangeretin offers such protection possibly through the inhibition of P-glycoprotein expression in macrophages needs clarification with the bio availability of these drugs under PGP inhibited conditions is a limitation of this study.


Subject(s)
Flavones , Lipopolysaccharides , STAT1 Transcription Factor , STAT3 Transcription Factor , Suppressor of Cytokine Signaling 3 Protein , Verapamil , Animals , Verapamil/pharmacology , STAT1 Transcription Factor/metabolism , Suppressor of Cytokine Signaling 3 Protein/metabolism , Suppressor of Cytokine Signaling 3 Protein/genetics , Flavones/pharmacology , Flavones/therapeutic use , Mice , STAT3 Transcription Factor/metabolism , Male , Sepsis/drug therapy , Sepsis/immunology , Sepsis/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Down-Regulation/drug effects , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Macrophages, Peritoneal/immunology , Cells, Cultured , Macrophages/drug effects , Macrophages/metabolism , Macrophages/immunology , Signal Transduction/drug effects , Up-Regulation/drug effects
13.
Cell Rep Med ; 5(5): 101520, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38642550

ABSTRACT

Pathogenic variants in MYH7 and MYBPC3 account for the majority of hypertrophic cardiomyopathy (HCM). Targeted drugs like myosin ATPase inhibitors have not been evaluated in children. We generate patient and variant-corrected iPSC-cardiomyocytes (CMs) from pediatric HCM patients harboring single variants in MYH7 (V606M; R453C), MYBPC3 (G148R) or digenic variants (MYBPC3 P955fs, TNNI3 A157V). We also generate CMs harboring MYBPC3 mono- and biallelic variants using CRISPR editing of a healthy control. Compared with isogenic and healthy controls, variant-positive CMs show sarcomere disorganization, higher contractility, calcium transients, and ATPase activity. However, only MYH7 and biallelic MYBPC3 variant-positive CMs show stronger myosin-actin binding. Targeted myosin ATPase inhibitors show complete rescue of the phenotype in variant-positive CMs and in cardiac Biowires to mirror isogenic controls. The response is superior to verapamil or metoprolol. Myosin inhibitors can be effective in genotypically diverse HCM highlighting the need for myosin inhibitor drug trials in pediatric HCM.


Subject(s)
Cardiac Myosins , Cardiomyopathy, Hypertrophic , Induced Pluripotent Stem Cells , Myocytes, Cardiac , Myosin Heavy Chains , Humans , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/drug effects , Cardiomyopathy, Hypertrophic/genetics , Cardiomyopathy, Hypertrophic/drug therapy , Cardiomyopathy, Hypertrophic/pathology , Cardiomyopathy, Hypertrophic/metabolism , Cardiac Myosins/genetics , Cardiac Myosins/metabolism , Child , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Myosin Heavy Chains/genetics , Myosin Heavy Chains/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Genotype , Myosins/metabolism , Myosins/genetics , Male , Female , Sarcomeres/metabolism , Sarcomeres/genetics
14.
J Cardiol Cases ; 29(4): 165-169, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38646079

ABSTRACT

Non-reentrant fascicular tachycardia (NRFT) developed in a 6-year-old Japanese boy. Because of drug-resistant recurrences, he received catheter mapping and ablation at age 10 years. An electrocardiogram exhibited a superior left-axis deviation, a right bundle branch block-type configuration, and relatively narrow QRS with sharp R wave. It suggested verapamil-sensitive ventricular tachycardia (VT), but showed no sensitivity to verapamil or reentrant characteristics in the electrophysiological study. Detailed VT mapping determined the earliest presystolic Purkinje potential on the left posterior fascicle at the mid-ventricular septum. Radiofrequency current applications to the lesion led to his NRFT-free life without restriction. Learning objectives: Purkinje-related idiopathic ventricular tachycardias (VTs) are commonly due to reentrant mechanisms, and non-reentrant fascicular tachycardia (NRFT) is a rare form of idiopathic VT in adults. Although it is crucial to distinguish NRFT from reentrant VTs, there is no information about the electrophysiological studies and the treatment effect in pediatric-onset NRFT.

15.
Biomedicines ; 12(4)2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38672259

ABSTRACT

Tendinopathy is a prevalent condition in orthopedics patients, exerting a profound impact on tendon functionality. However, its underlying mechanism remains elusive and the efficacy of pharmacological interventions continues to be suboptimal. Verapamil is a clinically used medicine with anti-inflammation and antioxidant functions. This investigation aimed to elucidate the impact of verapamil in tendinopathy and the underlying mechanisms through which verapamil ameliorates the severity of tendinopathy. In in vitro experiments, primary tenocytes were exposed to interleukin-1 beta (IL-1ß) along with verapamil at a concentration of 5 µM. In addition, an in vivo rat tendinopathy model was induced through the localized injection of collagenase into the Achilles tendons of rats, and verapamil was injected into these tendons at a concentration of 5 µM. The in vitro findings highlighted the remarkable ability of verapamil to attenuate extracellular matrix degradation and apoptosis triggered by inflammation in tenocytes stimulated by IL-1ß. Furthermore, verapamil was observed to significantly suppress the inflammation-related MAPK/NFκB pathway. Subsequent investigations revealed that verapamil exerts a remediating effect on mitochondrial dysfunction, which was achieved through activation of the Nrf2/HO-1 pathway. Nevertheless, the protective effect of verapamil was nullified with the utilization of the Nrf2 inhibitor ML385. In summary, the in vivo and in vitro results indicate that the administration of verapamil profoundly mitigates the severity of tendinopathy through suppression of inflammation and activation of the Nrf2/HO-1 pathway. These findings suggest that verapamil is a promising therapeutic agent for the treatment of tendinopathy, deserving further and expanded research.

16.
Arch Toxicol ; 98(6): 1827-1842, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38563869

ABSTRACT

Aminoglycosides are commonly used antibiotics for treatment of gram-negative bacterial infections, however, they might act on inner ear, leading to hair-cell death and hearing loss. Currently, there is no targeted therapy for aminoglycoside ototoxicity, since the underlying mechanisms of aminoglycoside-induced hearing impairments are not fully defined. This study aimed to investigate whether the calcium channel blocker verapamil and changes in intracellular & extracellular calcium could ameliorate aminoglycoside-induced ototoxicity in zebrafish. The present findings showed that a significant decreased number of neuromasts in the lateral lines of zebrafish larvae at 5 days' post fertilization after neomycin (20 µM) and gentamicin (20 mg/mL) exposure, which was prevented by verapamil. Moreover, verapamil (10-100 µM) attenuated aminoglycoside-induced toxic response in different external calcium concentrations (33-3300 µM). The increasing extracellular calcium reduced hair cell loss from aminoglycoside exposure, while lower calcium facilitated hair cell death. In contrast, calcium channel activator Bay K8644 (20 µM) enhanced aminoglycoside-induced ototoxicity and reversed the protective action of higher external calcium on hair cell loss. However, neomycin-elicited hair cell death was not altered by caffeine, ryanodine receptor (RyR) agonist, and RyR antagonists, including thapsigargin, ryanodine, and ruthenium red. The uptake of neomycin into hair cells was attenuated by verapamil and under high external calcium concentration. Consistently, the production of reactive oxygen species (ROS) in neuromasts exposed to neomycin was also reduced by verapamil and high external calcium. Significantly, zebrafish larvae when exposed to neomycin exhibited decreased swimming distances in reaction to droplet stimulus when compared to the control group. Verapamil and elevated external calcium effectively protected the impaired swimming ability of zebrafish larvae induced by neomycin. These data imply that prevention of hair cell damage correlated with swimming behavior against aminoglycoside ototoxicity by verapamil and higher external calcium might be associated with inhibition of excessive ROS production and aminoglycoside uptake through cation channels. These findings indicate that calcium channel blocker and higher external calcium could be applied to protect aminoglycoside-induced listening impairments.


Subject(s)
Anti-Bacterial Agents , Calcium Channel Blockers , Calcium , Gentamicins , Hair Cells, Auditory , Neomycin , Verapamil , Zebrafish , Animals , Calcium Channel Blockers/pharmacology , Calcium/metabolism , Verapamil/pharmacology , Neomycin/toxicity , Hair Cells, Auditory/drug effects , Hair Cells, Auditory/metabolism , Gentamicins/toxicity , Anti-Bacterial Agents/toxicity , Reactive Oxygen Species/metabolism , Ototoxicity/prevention & control , Aminoglycosides/toxicity , Lateral Line System/drug effects , Larva/drug effects , Hearing Loss/chemically induced , Hearing Loss/prevention & control
17.
Photobiomodul Photomed Laser Surg ; 42(4): 314-320, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38536111

ABSTRACT

Background: Acinetobacter baumannii, a nosocomial pathogen, poses a major public health problem due to generating resistance to several antimicrobial agents. Antimicrobial photodynamic inactivation (APDI) employs a nontoxic dye as a photosensitizer (PS) and light to produce reactive oxygen species that destroy bacterial cells. The intracellular concentration of PS could be affected by factors such as the function of efflux pumps to emit PS from the cytosol. Objective: To evaluate the augmentation effect of an efflux pump inhibitor, verapamil, three multidrug-resistant A. baumannii were subjected to APDI by erythrosine B (EB). Methods and results: The combination of EB and verapamil along with irradiation at 530 nm induced a lethal effect and more than 3 log colony-forming unit reduction to all A. baumannii strains in planktonic state. In contrast, EB and irradiation alone could produce only a sublethal effect on two of the strains. Conclusions: These data suggest that verapamil increases the intracellular concentration of EB, which potentiates the lethal efficacy of APDI. Verapamil could be applied with EB and green light to improve their antimicrobial efficacy against A. baumannii-localized infections.


Subject(s)
Acinetobacter baumannii , Drug Resistance, Multiple, Bacterial , Erythrosine , Fluorescent Dyes , Photosensitizing Agents , Verapamil , Acinetobacter baumannii/drug effects , Acinetobacter baumannii/radiation effects , Drug Resistance, Multiple, Bacterial/drug effects , Drug Resistance, Multiple, Bacterial/radiation effects , Photosensitizing Agents/pharmacology , Verapamil/pharmacology , Erythrosine/metabolism , Fluorescent Dyes/metabolism , Light
18.
Indian J Otolaryngol Head Neck Surg ; 76(1): 237-244, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38440636

ABSTRACT

Keloid, which forms as an excessive tissue response to trauma to the skin, is a benign, hyperproliferative, recurrent growth of dermal collagen without a quiescent or regressive period throughout the process of wound healing. The aim of this study was to evaluate patient satisfaction with treatment and to compare the efficacy of intralesional injection of triamcinolone acetonide against verapamil after keloidectomy with fillet flap in auricular keloids. Our study was Duration based prospective observational study with a Duration of two years from June 2021 till May 2023 with study population inclusive of 50 patients aged between 20 and 70 years having recurrent keloid(s) over the pinna of any size or site. Keloidectomy with fillet flap and intralesional injection of trimcinolone acetonide was performed on 25 patients (30 keloids) in Group A, and keloidectomy with fillet flap and intralesional injection of verapamil was performed on 25 patients (30 keloids) in Group B. With a recurrence rate of 27%, eight keloids in Group A patients had an early recurrence three months following surgery. At nine months, nine more mixed-type cases with a 30% recurrence rate resurfaced. Recurrence seen in eight keloids out of 28 showed a 28.57% recurrence rate 12 months following surgery. Three people in Group B with three sessile keloids experienced an early recurrence at three months after surgery, with a recurrence rate of 10%. At nine months, four more cases of mixed kind returned, with a recurrence rate of 13%. A recurrence rate of 14.28% was found in 4 of 28 keloids at 12 months postoperatively. The Patient and Observer Scar Assesment Scale scores (POSAS scores) were consistently higher than Beausang scores at 1 year, indicating high patient satisfaction compared to physician assessment in both groups A and B. A keloid recurrence-free interval of 11.36 months was obtained by the Kaplan-Meier survival test (p < 0.05) in group A. Keloid recurrence-free interval of 10.98 months was evaluated by the Kaplan-Meier survival test (p < 0.05) in group B. Among Keloidectomy with fillet flap surgery with intralesional injection of triamcinolone acetonide (group A) and keloidectomy with fillet surgery with intralesional injection of verapamil (group B), at each follow-up the success rate of group B was higher than group A indicating better trend of success in this group in terms of both absence of recurrence and absence of complications without statistically significant difference between them which shown both procedures more or less similar.

19.
Parasitol Res ; 123(3): 166, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38506929

ABSTRACT

The hemoparasite Trypanosoma equiperdum belongs to the Trypanozoon subgenus and includes several species that are pathogenic to animals and humans in tropical and subtropical areas across the world. As with all eukaryotic organisms, Ca2+ is essential for these parasites to perform cellular processes thus ensuring their survival across their life cycle. Despite the established paradigm to study proteins related to Ca2+ homeostasis as potential drug targets, so far little is known about Ca2+ entry into trypanosomes. Therefore, in the present study, the presence of a plasma membrane Ca2+-channel in T. equiperdum (TeCC), activated by sphingosine and inhibited by verapamil, is described. The TeCC was cloned and analyzed using bioinformatic resources, which confirmed the presence of several domains, motifs, and a topology similar to the Ca2+ channels found in higher eukaryotes. Biochemical and confocal microscopy assays using antibodies raised against an internal region of human L-type Ca2+ channels indicate the presence of a protein with similar predicted molar mass to the sequence analyzed, located at the plasma membrane of T. equiperdum. Physiological assays based on Fura-2 signals and Mn2+ quenching performed on whole parasites showed a unidirectional Ca2+ entry, which is activated by sphingosine and blocked by verapamil, with the distinctive feature of insensitivity to nifedipine and Bay K 8644. This suggests a second Ca2+ entry for T. equiperdum, different from the store-operated Ca2+ entry (SOCE) previously described. Moreover, the evidence presented here for the TeCC indicates molecular and pharmacological differences with their mammal counterparts, which deserve further studies to evaluate the potential of this channel as a drug target.


Subject(s)
Sphingosine , Trypanosoma , Animals , Humans , Sphingosine/pharmacology , Verapamil/pharmacology , Cell Membrane/metabolism , Calcium/metabolism , Mammals
20.
Front Biosci (Landmark Ed) ; 29(2): 47, 2024 Feb 04.
Article in English | MEDLINE | ID: mdl-38420828

ABSTRACT

BACKGROUND: The leaves of Origanum majorana (O. majorana) are traditionally renowned for treating diarrhea and gut spasms. This study was therefore planned to evaluate its methanolic extract. METHODS: Gas chromatography-mass spectrometry (GC-MS) was used to identify the phytochemicals, and Swiss albino mice were used for an in vivo antidiarrheal assay. Isolated rat ileum was used as an ex vivo assay model to study the possible antispasmodic effect and its mechanism(s). RESULTS: The GC-MS analysis of O. majorana detected the presence of 21 compounds, of which alpha-terpineol was a major constituent. In the antidiarrheal experiment, O. majorana showed a substantial inhibitory effect on diarrheal episodes in mice at an oral dosage of 200 mg/kg, resulting in 40% protection. Furthermore, an oral dosage of 400 mg/kg provided even greater protection, with 80% effectiveness. Similarly, loperamide showed 100% protection at oral doses of 10 mg/kg. O. majorana caused complete inhibition of carbachol (CCh, 1 µM) and high K+ (80 mM)-evoked spasms in isolated ileal tissues by expressing significantly higher potency (p < 0.05) against high K+ compared to CCh, similar to verapamil, a Ca++ antagonist. The verapamil-like predominant Ca++ ion inhibitory action of O. majorana was further confirmed in the ileal tissues that were made Ca++-free by incubating the tissues in a physiological salt solution having ethylenediaminetetraacetic acid (EDTA) as a chelating agent. The preincubation of O. majorana at increasing concentrations (0.3 and 1 mg/mL) shifted towards the right of the CaCl2-mediated concentration-response curves (CRCs) with suppression of the maximum contraction. Similarly, verapamil also caused non-specific suppression of Ca++ CRCs towards the right, as expected. CONCLUSIONS: Thus, this study conducted an analysis to determine the chemical constituents of the leaf extract of O. majorana and provided a detailed mechanistic basis for the medicinal use of O. majorana in hyperactive gut motility disorders.


Subject(s)
Antidiarrheals , Origanum , Rats , Mice , Animals , Antidiarrheals/pharmacology , Antidiarrheals/therapeutic use , Antidiarrheals/chemistry , Jejunum , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Extracts/chemistry , Castor Oil/pharmacology , Castor Oil/therapeutic use , Diarrhea/drug therapy , Verapamil/pharmacology , Verapamil/therapeutic use , Calcium Channels , Spasm/drug therapy
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