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1.
Pharm Res ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39044046

RESUMO

PURPOSE: We investigated whether short term infusion of propofol, a highly lipophilic agonist at GABAA receptors, which is in widespread clinical use as anesthetic and sedative, affects passive blood-brain barrier (BBB) permeability in vivo. METHODS: Mice were anesthetized with an intraperitoneal injection of ketamine/xylazine followed by a continuous IV infusion of propofol in lipid emulsion through a tail vein catheter. Control groups received ketamine/xylazine anesthesia and an infusion of Intralipid, or ketamine/xylazine anesthesia only. [13C12]sucrose as a permeability marker was injected as IV bolus 15 min after start of the infusions. Brain uptake clearance, Kin, of sucrose was calculated from the brain concentrations at 30 min and the area under the plasma-concentration time curve. We also measured the plasma and brain concentration of propofol at the terminal time point. RESULTS: The Kin value for propofol-infused mice was significantly higher, by a factor of 1.55 and 1.87, compared to the Intralipid infusion and the ketamine/xylazine groups, respectively, while the control groups were not significantly different. No difference was seen in the expression levels of tight junction proteins in brain across all groups. The propofol plasma concentration at the end of infusion (10.7 µM) matched the clinically relevant range of blood concentrations reported in humans, while concentration in brain was 2.5-fold higher than plasma. CONCLUSIONS: Propofol at clinical plasma concentrations acutely increases BBB permeability, extending our previous results with volatile anesthetics to a lipophilic injectable agent. This prompts further exploration, potentially refining clinical practices and ensuring safety, especially during extended propofol infusion schemes.

2.
Pharm Res ; 40(11): 2747-2758, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37833570

RESUMO

PURPOSE: There is growing interest in seeking pharmacological activation of neurolysin (Nln) for stroke treatment. Discovery of central nervous system drugs remains challenging due to the protection of the blood-brain barrier (BBB). The previously reported peptidomimetic Nln activators display unsatisfactory BBB penetration. Herein, we investigate the next generation of non-peptidomimetic Nln activators with high BBB permeability. METHODS: A BBB-mimicking model was used to evaluate their in vitro BBB permeability. Protein binding, metabolic stability, and efflux assays were performed to determine their unbound fraction, half-lives in plasma and brains, and dependence of BBB transporter P-glycoprotein (P-gp). The in vivo pharmacokinetic profiles were elucidated in healthy and stroke mice. RESULTS: Compounds KS52 and KS73 out of this generation exhibit improved peptidase activity and BBB permeability compared to the endogenous activator and previous peptidomimetic activators. They show reasonable plasma and brain protein binding, improved metabolic stability, and independence of P-gp-mediated efflux. In healthy animals, they rapidly distribute into brains and reach peak levels of 18.69% and 12.10% injected dose (ID)/ml at 10 min. After 4 h, their total brain concentrations remain 7.78 and 12.34 times higher than their A50(minimal concentration required for enhancing 50% peptidase activity). Moreover, the ipsilateral hemispheres of stroke animals show comparable uptake to the corresponding contralateral hemispheres and healthy brains. CONCLUSIONS: This study provides essential details about the pharmacokinetic properties of a new generation of potent non-peptidomimetic Nln activators with high BBB permeability and warrants the future development of these agents as potential neuroprotective pharmaceutics for stroke treatment.


Assuntos
Peptidomiméticos , Acidente Vascular Cerebral , Camundongos , Animais , Barreira Hematoencefálica/metabolismo , Peptidomiméticos/metabolismo , Metaloendopeptidases/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Permeabilidade
3.
Front Pharmacol ; 14: 1227145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693917

RESUMO

Introduction: Despite the prevalence of the perception that electronic cigarettes (e-cig) are a safer alternative to tobacco smoke, growing concern about their potential toxic impact warrants adequate investigation focusing on special populations like maternal and pediatric groups. This study evaluated the consequences of maternal e-cig use on neonatal neuroinflammation, oxidative stress, and mitochondrial function in primary cultured neurons and postnatal day (PD) 7 and 90 brain. Methodology: Pregnant CD1 mice were exposed to e-cig vapor (2.4% nicotine) from gestational day 5 (E5) till PD7, and the primary neurons were isolated from pups at E16/17. Cellular total reactive oxygen species (ROS) and mitochondrial superoxide were measured in primary neurons using CM-H2DCFDA and Mitosox red, respectively. Mitochondrial function was assessed by Seahorse XF Cell Mitostress analysis. The level of pro-inflammatory cytokines was measured in primary neurons and PD7 and PD90 brains by RT-PCR and immunobead assay. Western blot analysis evaluated the expression of antioxidative markers (SOD-2, HO-1, NRF2, NQO1) and that of the proinflammatory modulator NF-κB. Results: Significantly higher level of total cellular ROS (p < 0.05) and mitochondrial superoxide (p < 0.01) was observed in prenatally e-cig-exposed primary neurons. We also observed significantly reduced antioxidative marker expression and increased proinflammatory modulator and cytokines expression in primary neurons and PD7 (p < 0.05) but not in PD90 postnatal brain. Conclusion: Our findings suggest that prenatal e-cig exposure induces postnatal neuroinflammation by promoting oxidative stress (OS), increasing cytokines' levels, and disrupting mitochondrial function. These damaging events can alter the fetal brain's immune functions, making such offspring more vulnerable to brain insults.

4.
Pharmaceutics ; 15(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37242599

RESUMO

Our lab previously established that metformin, a first-line type two diabetes treatment, activates the Nrf2 pathway and improves post-stroke recovery. Metformin's brain permeability value and potential interaction with blood-brain barrier (BBB) uptake and efflux transporters are currently unknown. Metformin has been shown to be a substrate of organic cationic transporters (Octs) in the liver and kidneys. Brain endothelial cells at the BBB have been shown to express Octs; thus, we hypothesize that metformin uses Octs for its transport across the BBB. We used a co-culture model of brain endothelial cells and primary astrocytes as an in vitro BBB model to conduct permeability studies during normoxia and hypoxia using oxygen-glucose deprivation (OGD) conditions. Metformin was quantified using a highly sensitive LC-MS/MS method. We further checked Octs protein expression using Western blot analysis. Lastly, we completed a plasma glycoprotein (P-GP) efflux assay. Our results showed that metformin is a highly permeable molecule, uses Oct1 for its transport, and does not interact with P-GP. During OGD, we found alterations in Oct1 expression and increased permeability for metformin. Additionally, we showed that selective transport is a key determinant of metformin's permeability during OGD, thus, providing a novel target for improving ischemic drug delivery.

5.
Fluids Barriers CNS ; 20(1): 17, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899432

RESUMO

Electronic nicotine delivery systems (ENDS), also commonly known as electronic cigarettes (e-cigs) are considered in most cases as a safer alternative to tobacco smoking and therefore have become extremely popular among all age groups and sex. It is estimated that up to 15% of pregnant women are now using e-cigs in the US which keeps increasing at an alarming rate. Harmful effects of tobacco smoking during pregnancy are well documented for both pregnancy and postnatal health, however limited preclinical and clinical studies exist to evaluate the long-term effects of prenatal e-cig exposure on postnatal health. Therefore, the aim of our study is to evaluate the effect of maternal e-cig use on postnatal blood-brain barrier (BBB) integrity and behavioral outcomes of mice of varying age and sex. In this study, pregnant CD1 mice (E5) were exposed to e-Cig vapor (2.4% nicotine) until postnatal day (PD) 7. Weight of the offspring was measured at PD0, PD7, PD15, PD30, PD45, PD60 and PD90. The expression of structural elements of the BBB, tight junction proteins (ZO-1, claudin-5, occludin), astrocytes (GFAP), pericytes (PDGFRß) and the basement membrane (laminin α1, laminin α4), neuron specific marker (NeuN), water channel protein (AQP4) and glucose transporter (GLUT1) were analyzed in both male and female offspring using western blot and immunofluorescence. Estrous cycle was recorded by vaginal cytology method. Long-term motor and cognitive functions were evaluated using open field test (OFT), novel object recognition test (NORT) and morris water maze test (MWMT) at adolescence (PD 40-45) and adult (PD 90-95) age. In our study, significantly reduced expression of tight junction proteins and astrocyte marker were observed in male and female offspring until PD 90 (P < 0.05). Additionally, prenatally e-cig exposed adolescent and adult offspring showed impaired locomotor, learning, and memory function compared to control offspring (P < 0.05). Our findings suggest that prenatal e-cig exposure induces long-term neurovascular changes of neonates by disrupting postnatal BBB integrity and worsening behavioral outcomes.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Vaping , Gravidez , Feminino , Animais , Masculino , Camundongos , Humanos , Barreira Hematoencefálica , Nicotina , Proteínas de Junções Íntimas
7.
Fluids Barriers CNS ; 19(1): 74, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085043

RESUMO

BACKGROUND: The short and long-term health effects of JUUL electronic cigarette (e-Cig) are largely unknown and warrant extensive research. We hypothesized that JUUL exposure could cause cerebrovascular toxicities impacting the progression and outcome of ischemic stroke comparable to tobacco smoke (TS) exposure. METHODS: We exposed male C57 mice to TS/JUUL vapor for 14 days. LCMS/MS was used to measure brain and plasma nicotine and cotinine level. Transient middle cerebral artery occlusion (tMCAO) followed by reperfusion was used to mimic ischemic stroke. Plasma levels of IL-6 and thrombomodulin were assessed by enzyme-linked immunosorbent assay. At the same time, western blotting was used to study blood-brain barrier (BBB) tight junction (TJ) proteins expression and key inflammatory and oxidative stress markers. RESULTS: tMCAO upregulated IL-6 and decreased plasma thrombomodulin levels. Post-ischemic brain injury following tMCAO was significantly worsened by JUUL/TS pre-exposure. TJ proteins expression was also downregulated by JUUL/TS pre-exposure after tMCAO. Like TS, exposure to JUUL downregulated the expression of the antioxidant Nrf2. ICAM-1 was upregulated in mice subjected to tMCAO following pre-exposure to TS or JUUL, with a greater effect of TS than JUUL. CONCLUSIONS: These results suggest that JUUL exposure could negatively impact the cerebrovascular system, although to a lesser extent than TS exposure.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , AVC Isquêmico , Animais , Barreira Hematoencefálica , Interleucina-6 , Masculino , Camundongos , Trombomodulina , Proteínas de Junções Íntimas
8.
Int J Mol Sci ; 23(15)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35955647

RESUMO

Proper regulation of energy metabolism in the brain is crucial for maintaining brain activity in physiological and different pathophysiological conditions. Ischemic stroke has a complex pathophysiology which includes perturbations in the brain energy metabolism processes which can contribute to worsening of brain injury and stroke outcome. Smoking and diabetes are common risk factors and comorbid conditions for ischemic stroke which have also been associated with disruptions in brain energy metabolism. Simultaneous presence of these conditions may further alter energy metabolism in the brain leading to a poor clinical prognosis after an ischemic stroke event. In this review, we discuss the possible effects of smoking and/or diabetes on brain glucose utilization and mitochondrial energy metabolism which, when present concurrently, may exacerbate energy metabolism in the ischemic brain. More research is needed to investigate brain glucose utilization and mitochondrial oxidative metabolism in ischemic stroke in the presence of smoking and/or diabetes, which would provide further insights on the pathophysiology of these comorbid conditions and facilitate the development of therapeutic interventions.


Assuntos
Isquemia Encefálica , Diabetes Mellitus , AVC Isquêmico , Acidente Vascular Cerebral , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Diabetes Mellitus/metabolismo , Metabolismo Energético , Glucose/metabolismo , Humanos , Fumar/efeitos adversos , Acidente Vascular Cerebral/complicações
9.
Fluids Barriers CNS ; 19(1): 46, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672716

RESUMO

BACKGROUND: Knowledge of the entry receptors responsible for SARS-CoV-2 is key to understand the neural transmission and pathogenesis of COVID-19 characterized by a neuroinflammatory scenario. Understanding the brain distribution of angiotensin converting enzyme 2 (ACE2), the primary entry receptor for SARS-CoV-2, remains mixed. Smoking has been shown as a risk factor for COVID-19 severity and it is not clear how smoking exacerbates the neural pathogenesis in smokers. METHODS: Immunohistochemistry, real-time PCR and western blot assays were used to systemically examine the spatial-, cell type- and isoform-specific expression of ACE2 in mouse brain and primary cultured brain cells. Experimental smoking exposure was conducted to evaluate the effect of smoking on brain expression. RESULTS: We observed ubiquitous expression of ACE2 but uneven brain distribution, with high expression in the cerebral microvasculature, medulla oblongata, hypothalamus, subventricular zones, and meninges around medulla oblongata and hypothalamus. Co-staining with cell type-specific markers demonstrates ACE2 is primarily expressed in astrocytes around the microvasculature, medulla oblongata, hypothalamus, ventricular and subventricular zones of cerebral ventricles, and subependymal zones in rhinoceles and rostral migratory streams, radial glial cells in the lateral ventricular zones, tanycytes in the third ventricle, epithelial cells and stroma in the cerebral choroid plexus, as well as cerebral pericytes, but rarely detected in neurons and cerebral endothelial cells. ACE2 expression in astrocytes is further confirmed in primary cultured cells. Furthermore, isoform-specific analysis shows astrocyte ACE2 has the peptidase domain responsible for SARS-CoV-2 entry, indicating astrocytes are indeed vulnerable to SARS-CoV-2 infection. Finally, our data show experimental tobacco smoking and electronic nicotine vaping exposure increase proinflammatory and/or immunomodulatory cytokine IL-1a, IL-6 and IL-5 without significantly affecting ACE2 expression in the brain, suggesting smoking may pre-condition a neuroinflammatory state in the brain. CONCLUSIONS: The present study demonstrates a spatial- and cell type-specific expression of ACE2 in the brain, which might help to understand the acute and lasting post-infection neuropsychological manifestations in COVID-19 patients. Our data highlights a potential role of astrocyte ACE2 in the neural transmission and pathogenesis of COVID-19. This also suggests a pre-conditioned neuroinflammatory and immunocompromised scenario might attribute to exacerbated COVID-19 severity in the smokers.


Assuntos
COVID-19 , Vaping , Enzima de Conversão de Angiotensina 2 , Animais , Astrócitos , Células Endoteliais , Humanos , Camundongos , SARS-CoV-2 , Fumar/efeitos adversos , Transmissão Sináptica , Fumar Tabaco
10.
Neurotoxicology ; 89: 140-160, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35150755

RESUMO

Accumulating evidence suggests that the detrimental effect of nicotine and tobacco smoke on the central nervous system (CNS) is caused by the neurotoxic role of nicotine on blood-brain barrier (BBB) permeability, nicotinic acetylcholine receptor expression, and the dopaminergic system. The ultimate consequence of these nicotine associated neurotoxicities can lead to cerebrovascular dysfunction, altered behavioral outcomes (hyperactivity and cognitive dysfunction) as well as future drug abuse and addiction. The severity of these detrimental effects can be associated with several biological determinants. Sex and age are two important biological determinants which can affect the pharmacokinetics and pharmacodynamics of several systemically available substances, including nicotine. With regard to sex, the availability of gonadal hormone is impacted by the pregnancy status and menstrual cycle resulting in altered metabolism rate of nicotine. Additionally, the observed lower smoking cessation rate in females compared to males is a consequence of differential effects of sex on pharmacokinetics and pharmacodynamics of nicotine. Similarly, age-dependent alterations in the pharmacokinetics and pharmacodynamics of nicotine have also been observed. One such example is related to severe vulnerability of adolescence towards addiction and long-term behavioral changes which may continue through adulthood. Considering the possible neurotoxic effects of nicotine on the central nervous system and the deterministic role of sex as well as age on these neurotoxic effects of smoking, it has become important to consider sex and age to study nicotine induced neurotoxicity and development of treatment strategies for combating possible harmful effects of nicotine. In the future, understanding the role of sex and age on the neurotoxic actions of nicotine can facilitate the individualization and optimization of treatment(s) to mitigate nicotine induced neurotoxicity as well as smoking cessation therapy. Unfortunately, however, no such comprehensive study is available which has considered both the sex- and age-dependent neurotoxicity of nicotine, as of today. Hence, the overreaching goal of this review article is to analyze and summarize the impact of sex and age on pharmacokinetics and pharmacodynamics of nicotine and possible neurotoxic consequences associated with nicotine in order to emphasize the importance of including these biological factors for such studies.


Assuntos
Nicotina , Poluição por Fumaça de Tabaco , Fatores Biológicos , Feminino , Humanos , Masculino , Nicotina/farmacologia , Gravidez , Fumar/efeitos adversos , Nicotiana
11.
Pharmaceutics ; 13(11)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34834200

RESUMO

The blood-brain barrier (BBB) is a fundamental component of the central nervous system (CNS). Its functional and structural integrity is vital to maintain the homeostasis of the brain microenvironment by controlling the passage of substances and regulating the trafficking of immune cells between the blood and the brain. The BBB is primarily composed of highly specialized microvascular endothelial cells. These cells' special features and physiological properties are acquired and maintained through the concerted effort of hemodynamic and cellular cues from the surrounding environment. This complex multicellular system, comprising endothelial cells, astrocytes, pericytes, and neurons, is known as the neurovascular unit (NVU). The BBB strictly controls the transport of nutrients and metabolites into brain parenchyma through a tightly regulated transport system while limiting the access of potentially harmful substances via efflux transcytosis and metabolic mechanisms. Not surprisingly, a disruption of the BBB has been associated with the onset and/or progression of major neurological disorders. Although the association between disease and BBB disruption is clear, its nature is not always evident, specifically with regard to whether an impaired BBB function results from the pathological condition or whether the BBB damage is the primary pathogenic factor prodromal to the onset of the disease. In either case, repairing the barrier could be a viable option for treating and/or reducing the effects of CNS disorders. In this review, we describe the fundamental structure and function of the BBB in both healthy and altered/diseased conditions. Additionally, we provide an overview of the potential therapeutic targets that could be leveraged to restore the integrity of the BBB concomitant to the treatment of these brain disorders.

12.
Int J Mol Sci ; 21(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486196

RESUMO

The recently discovered novel coronavirus, SARS-CoV-2 (COVID-19 virus), has brought the whole world to standstill with critical challenges, affecting both health and economic sectors worldwide. Although initially, this pandemic was associated with causing severe pulmonary and respiratory disorders, recent case studies reported the association of cerebrovascular-neurological dysfunction in COVID-19 patients, which is also life-threatening. Several SARS-CoV-2 positive case studies have been reported where there are mild or no symptoms of this virus. However, a selection of patients are suffering from large artery ischemic strokes. Although the pathophysiology of the SARS-CoV-2 virus affecting the cerebrovascular system has not been elucidated yet, researchers have identified several pathogenic mechanisms, including a role for the ACE2 receptor. Therefore, it is extremely crucial to identify the risk factors related to the progression and adverse outcome of cerebrovascular-neurological dysfunction in COVID-19 patients. Since many articles have reported the effect of smoking (tobacco and cannabis) and vaping in cerebrovascular and neurological systems, and considering that smokers are more prone to viral and bacterial infection compared to non-smokers, it is high time to explore the probable correlation of smoking in COVID-19 patients. Herein, we have reviewed the possible role of smoking and vaping on cerebrovascular and neurological dysfunction in COVID-19 patients, along with potential pathogenic mechanisms associated with it.


Assuntos
Transtornos Cerebrovasculares/epidemiologia , Infecções por Coronavirus/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Pneumonia Viral/epidemiologia , Fumar Tabaco/epidemiologia , Vaping/epidemiologia , COVID-19 , Humanos , Pandemias
13.
Fluids Barriers CNS ; 17(1): 22, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32178700

RESUMO

The blood-brain barrier (BBB) is a fundamental component of the central nervous system. Its functional and structural integrity is vital in maintaining the homeostasis of the brain microenvironment. On the other hand, the BBB is also a major hindering obstacle for the delivery of effective therapies to treat disorders of the Central Nervous System (CNS). Over time, various model systems have been established to simulate the complexities of the BBB. The development of realistic in vitro BBB models that accurately mimic the physiological characteristics of the brain microcapillaries in situ is of fundamental importance not only in CNS drug discovery but also in translational research. Successful modeling of the Neurovascular Unit (NVU) would provide an invaluable tool that would aid in dissecting out the pathological factors, mechanisms of action, and corresponding targets prodromal to the onset of CNS disorders. The field of BBB in vitro modeling has seen many fundamental changes in the last few years with the introduction of novel tools and methods to improve existing models and enable new ones. The development of CNS organoids, organ-on-chip, spheroids, 3D printed microfluidics, and other innovative technologies have the potential to advance the field of BBB and NVU modeling. Therefore, in this review, summarize the advances and progress in the design and application of functional in vitro BBB platforms with a focus on rapidly advancing technologies.


Assuntos
Barreira Hematoencefálica , Modelos Biológicos , Animais , Humanos
14.
Artigo em Inglês | MEDLINE | ID: mdl-31084596

RESUMO

OBJECTIVES: Inflammation is our body's normal defense mechanism, but in some cases, it may be responsible for causing different kinds of disorders. Several antiinflammatory drugs are present for the treatment of these disorders; however, the conventional anti-inflammatory drugs cause side effects when used in the long term and therefore, it is better to use them in a low dose for a shorter duration of time. This study was designed to find out whether there is an augmentation of the therapeutic effectiveness of the antiinflammatory drugs like diclofenac sodium (NSAID), prednisolone (steroid) and atorvastatin (statin) when used in combination with ascorbic acid (antioxidant). METHODS: Wistar Rats (n=144) were selected and divided into 24 groups of 6 rats in each. Carrageenan and formalin were used to induce local inflammation and neuropsychiatric effects, respectively. The inhibitions of such responses were measured after administering a drug alone and in combination with ascorbic acid. RESULTS: In case of carrageenan mediated inflammation, the combination of 5 mg/kg diclofenac and 200 mg/kg ascorbic acid gave the highest inhibition of 74.19% compared to other groups of drugs. The combination of 5 mg/kg diclofenac and 200 mg/kg ascorbic acid gave 97.25% inhibition for formalin-mediated inflammation group. In both cases, combination therapy showed statistically significant anti-inflammatory activities compared to monotherapy (p values <0.05). CONCLUSION: All the data clearly indicate new combinations of drug therapy comprising diclofenac sodium, prednisolone, atorvastatin with ascorbic acid, which may be more effective against both local edema and the neuropsychiatric effect caused due to inflammation.


Assuntos
Ácido Ascórbico/farmacologia , Atorvastatina/farmacologia , Diclofenaco/farmacologia , Prednisolona/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Modelos Animais de Doenças , Combinação de Medicamentos , Cálculos da Dosagem de Medicamento , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inflamação/tratamento farmacológico , Ratos , Resultado do Tratamento
15.
Pharm Res ; 37(1): 12, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873819

RESUMO

Intraperitoneal (IP) route of drug administration in laboratory animals is a common practice in many in vivo studies of disease models. While this route is an easy to master, quick, suitable for chronic treatments and with low impact of stress on laboratory rodents, there is a common concern that it may not be an acceptable route for drug administration in experimental studies. The latter is likely due to sparsity of information regarding pharmacokinetics of pharmacological agents and the mechanisms through which agents get systemic exposure after IP administration. In this review, we summarize the main mechanisms involved in bioavailability of IP administered drugs and provide examples of pharmacokinetic profiles for small and large molecules in comparison to other routes of administration. We conclude with a notion that IP administration of drugs in experimental studies involving rodents is a justifiable route for pharmacological and proof-of-concept studies where the goal is to evaluate the effect(s) of target engagement rather than properties of a drug formulation and/or its pharmacokinetics for clinical translation.


Assuntos
Composição de Medicamentos/métodos , Injeções Intraperitoneais/métodos , Preparações Farmacêuticas/química , Animais , Disponibilidade Biológica , Vias de Administração de Medicamentos , Humanos , Injeções Subcutâneas/métodos , Modelos Animais , Tamanho da Partícula , Farmacocinética , Transdução de Sinais
16.
Curr Cardiol Rep ; 21(10): 111, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463564

RESUMO

Tobacco continues to kill about 0.48 million Americans per year and there are currently 34.3 million smokers in the USA. As a consequence of the First Surgeon General's Report on Tobacco in 1964, tobacco control interventions on part of the government led to a significant decline in conventional tobacco product usage over the last few decades. However, more recently, a new entity in the form of electronic cigarettes has risen rapidly and has exposed a younger population to a plethora of dangerous consequences. Looking at e-cigarettes from the perspective of tobacco control however raises a lot of challenges. There is little doubt that existing smokers of combustible cigarettes who switch to e-cigarettes will be switching to a less harmful product. However, if the younger generation begins using e-cigarettes as a result of targeted marketing, appealing flavors and 'safer alternative' perception, decades of progress made in conventional tobacco control will be negated. Governments at the federal, state, and local levels have a mandate to once again implement new public health policies to ensure that non-conventional tobacco products like e-cigarettes are available as smoking cessation tools for existing smokers but at the same time do not play a role in ruining the health of future generations through addiction and disease. PURPOSE OF REVIEW: To review the present scenario of regulations and policies impacting public health with respect to electronic nicotine delivery systems (ENDS) with the objective of providing a meaningful and balanced view of the challenges at hand with plausible recommendations. RECENT FINDINGS: Nicotine in tobacco is known to cause addiction and dependence. It is particularly potent in children and young adults. E-cigarettes can deliver high concentrations of nicotine, and these concentrations can vary depending on the numerous constituents within the e-cigarette which vary greatly from one another. Use of e-cigarettes is implicated as a risk factor for future cigarette use in young adults. Moreover, e-cigarette usage patterns also depend on several sociodemographic factors. Banning tobacco products has shown to reduce smoking risk in youth and as such, strong e-cigarette regulation measures are needed for prevention. Effective regulation of ENDS faces a multitude of challenges. One such challenge is to prevent youth and non-smokers from getting habituated to nicotine through e-cigarettes. The intention of tobacco companies to sustain sales through harmful marketing strategies that tone down the risks and highlight e-cigarettes as a "much safer alternative" while promoting flavors appealing to children should be immediately prohibited. Another hazard is the endorsement of ENDS as devices meant for enhancing social interaction which opens a path for youth to make erroneous choices under peer pressure. On the other hand, several studies have reported that e-cigarettes significantly reduce an existing smoker's risk of being exposed to toxic tobacco smoke constituents that are normally present in cigarette smoke. This leads to the conclusions that e-cigarettes can be a tool for smoking cessation for current smokers. Public policy must take a multi-dimensional approach to balance these two extremes.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Política de Saúde , Saúde Pública , Abandono do Hábito de Fumar , Adolescente , Criança , Humanos , Política Pública , Fumar , Estados Unidos , Adulto Jovem
17.
Front Pharmacol ; 10: 1481, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920665

RESUMO

Apart from being used as a medicine, cannabis or marijuana is the most widely abused recreational drug all over the world. The legalization and decriminalization of cannabis in Canada and various states of USA may be the underlying reason of the widespread popularity of it among young population. Various studies have reported about the relationship between cannabis use and different detrimental effects like cardiovascular, cerebrovascular, and neurological complications among different age groups. Specifically, the young population is getting adversely affected by this, harmful yet, readily accessible recreational drug. Although the mechanism behind cannabis mediated neurological and cerebrovascular complications has not been elucidated yet, the results of these studies have confirmed the association of these diseases with cannabis. Given the lack of comprehensive study relating these harmful complications with cannabis use, the aim of this narrative literature review article is to evaluate and summarize current studies on cannabis consumption and cerebrovascular/neurological diseases along with the leading toxicological mechanisms.

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