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1.
Cells ; 13(3)2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38334654

ABSTRACT

Noradrenaline and adrenaline, and their cognate receptors, are currently accepted to participate in cancer progression. They may also participate in cancer initiation, although their role in this phase is much less explored. The aim of this work was to study the influence of adrenergic stimulation in several processes related to breast cancer carcinogenesis, using several adrenergic agonists in the MCF-10A non-tumorigenic breast cells. Activation of the ß-adrenoceptors promoted an epithelial phenotype in MCF-10A cells, revealed by an increased expression of the epithelial marker E-cadherin and a decrease in the mesenchymal markers, N-cadherin and vimentin. MCF-10A cell motility and migration were also impaired after the ß-adrenoceptors activation. Concomitant with this effect, ß-adrenoceptors decrease cell protrusions (lamellipodia and filopodia) while increasing cell adhesion. Activation of the ß-adrenoceptors also decreases MCF-10A cell proliferation. When the MCF-10A cells were cultured under low attachment conditions, activation the of ß- (likely ß2) or of α2-adrenoceptors had protective effects against cell death, suggesting a pro-survival role of these adrenoceptors. Overall, our results showed that, in breast cells, adrenoceptor activation (mainly through ß-adrenoceptors) may be a risk factor in breast cancer by inducing some cancer hallmarks, providing a mechanistic explanation for the increase in breast cancer incidences that may be associated with conditions that cause massive adrenergic stimulation, such as stress.


Subject(s)
Breast Neoplasms , Breast , Humans , Female , Breast/metabolism , Breast Neoplasms/metabolism , Epithelial Cells/metabolism , Adrenergic Agents/metabolism , Carcinogenesis/metabolism
3.
Cancers (Basel) ; 15(15)2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37568828

ABSTRACT

Perilipins (PLINs) are the most abundant proteins in lipid droplets (LD). These LD-associated proteins are responsible for upgrading LD from inert lipid storage structures to fully functional organelles, fundamentally integrated in the lipid metabolism. There are five distinct perilipins (PLIN1-5), each with specific expression patterns and metabolic activation, but all capable of regulating the activity of lipases on LD. This plurality creates a complex orchestrated mechanism that is directly related to the healthy balance between lipogenesis and lipolysis. Given the essential role of PLINs in the modulation of the lipid metabolism, these proteins can become interesting targets for the treatment of lipid-associated diseases. Since reprogrammed lipid metabolism is a recognized cancer hallmark, and obesity is a known risk factor for cancer and other comorbidities, the modulation of PLINs could either improve existing treatments or create new opportunities for the treatment of these diseases. Even though PLINs have not been, so far, directly considered for pharmacological interventions, there are many established drugs that can modulate PLINs activity. Therefore, the aim of this study is to assess the involvement of PLINs in diseases related to lipid metabolism dysregulation and whether PLINs can be viewed as potential therapeutic targets for cancer and obesity.

5.
Rev Port Cardiol ; 42(4): 373-383, 2023 04.
Article in English, Portuguese | MEDLINE | ID: mdl-36893838

ABSTRACT

SARS-CoV-2 infection and its clinical manifestations (COVID-19) quickly evolved to a pandemic and a global public health emergency. The limited effectivity of available treatments aimed at reducing virus replication and the lessons learned from other coronavirus infections (SARS-CoV-1 or NL63) that share the internalization process of SARS-CoV-2, led us to revisit the COVID-19 pathogenesis and potential treatments. Virus protein S binds to the angiotensin-converting enzyme 2 (ACE2) initiating the internalization process. Endosome formation removes ACE2 from the cellular membrane preventing its counter-regulative effect mediated by the metabolism of angiotensin II to angiotensin (1-7). Internalized virus-ACE2 complexes have been identified for these coronaviruses. SARS-CoV-2 presents the highest affinity for ACE2 and produces the most severe symptoms. Assuming ACE2 internalization is the trigger for COVID-19 pathogenesis, accumulation of angiotensin II can be viewed as the potential cause of symptoms. Angiotensin II is a strong vasoconstrictor, but has also important roles in hypertrophy, inflammation, remodeling, and apoptosis. Higher levels of ACE2 in the lungs explain the acute respiratory distress syndrome as primary symptoms. Most of the described findings and clinical manifestations of COVID-19, including increased interleukin levels, endothelial inflammation, hypercoagulability, myocarditis, dysgeusia, inflammatory neuropathies, epileptic seizures and memory disorders can be explained by excessive angiotensin II levels. Several meta-analyses have demonstrated that previous use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers were associated with better prognosis for COVID-19. Therefore, pragmatic trials to assess the potential therapeutic benefits of renin-angiotensin-aldosterone system inhibitors should be urgently promoted by health authorities to widen the therapeutic options for COVID-19.


Subject(s)
COVID-19 , Renin-Angiotensin System , Humans , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/pharmacology , SARS-CoV-2/metabolism , Angiotensin II/metabolism , Angiotensin II/pharmacology , Peptidyl-Dipeptidase A/metabolism , Peptidyl-Dipeptidase A/pharmacology , Inflammation
6.
Int J Mol Sci ; 24(1)2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36614209

ABSTRACT

Physiologically, ß-adrenoceptors are major regulators of lipid metabolism, which may be reflected in alterations in lipid droplet dynamics. ß-adrenoceptors have also been shown to participate in breast cancer carcinogenesis. Since lipid droplets may be seen as a hallmark of cancer, the present study aimed to investigate the role of ß-adrenoceptors in the regulation of lipid droplet dynamics in MCF-7 breast cancer cells. Cells were treated for up to 72 h with adrenaline (an endogenous adrenoceptor agonist), isoprenaline (a non-selective ß-adrenoceptor agonist) and salbutamol (a selective ß2-selective agonist), and their effects on lipid droplets were evaluated using Nile Red staining. Adrenaline or isoprenaline, but not salbutamol, caused a lipid-accumulating phenotype in the MCF-7 cells. These effects were significantly reduced by selective ß1- and ß3-antagonists (10 nM atenolol and 100 nM L-748,337, respectively), indicating a dependence on both ß1- and ß3-adrenoceptors. These effects were dependent on the cAMP signalling pathway, involving both protein kinase A (PKA) and cAMP-dependent guanine-nucleotide-exchange (EPAC) proteins: treatment with cAMP-elevating agents (forskolin or 8-Br-cAMP) induced lipid droplet accumulation, whereas either 1 µM H-89 or 1 µM ESI-09 (PKA or EPAC inhibitors, respectively) abrogated this effect. Taken together, the present results demonstrate the existence of a ß-adrenoceptor-mediated regulation of lipid droplet dynamics in breast cancer cells, likely involving ß1- and ß3-adrenoceptors, revealing a new mechanism by which adrenergic stimulation may influence cancer cell metabolism.


Subject(s)
Lipid Droplets , Neoplasms , Humans , Isoproterenol/pharmacology , MCF-7 Cells , Cyclic AMP-Dependent Protein Kinases , Adrenergic beta-Agonists/pharmacology , Receptors, Adrenergic, beta , Albuterol/pharmacology , Epinephrine , Guanine Nucleotide Exchange Factors , Adrenergic beta-Antagonists/pharmacology
7.
Eur J Med Res ; 27(1): 86, 2022 Jun 04.
Article in English | MEDLINE | ID: mdl-35659086

ABSTRACT

BACKGROUND: Resistant chronic migraine is a highly disabling condition which is very difficult to treat. The majority of the treatments for migraine prophylaxis are nonspecific and present weak safety profiles, leading to low adherence and discontinuation. Currently, monoclonal antibodies (mAb) targeting the trigeminal sensory neuropeptide, calcitonin gene-related peptide (CGRP), are available for migraine prophylaxis being the first drugs developed specifically to target migraine pathogenesis. The main objective of the current work is to carry out a systematic review of randomised controlled trials that specifically analyse the effectivity and safety of anti-CGRP mAb, comparatively to placebo, in patients with resistant chronic migraine and possibly fill the literature gap or be a source of information to health professionals. Additionally the current knowledge on migraine, particularly resistant chronic migraine, was revisited and summarised. METHODS: Literature search was carried out on MEDLINE, Scopus, Science Direct and ClinicalTrials.gov database, from inception to December 2021. Articles were selected according to prespecified criteria of inclusion and exclusion. Efficacy and safety outcomes included were: change from baseline in monthly migraine days (MMD); ≥50% reduction of MMD values from baseline; change from baseline in monthly acute migraine-specific medication days (MAMD); Migraine-specific Quality of Life Questionnaire (MSQ); and registered adverse events. Additionally, we used the Cochrane risk of bias tool (RoB 2) to assess the risk of bias of the included studies. RESULTS: Four studies were included in this systematic review, involving 2811 resistant chronic migraine patients, 667 in a study using erenumab, 838 in a study using fremanezumab and 1306 in two studies using galcanezumab. When compared to placebo, all investigated anti-CGRP mAb and respective doses demonstrate effectiveness in decreasing MMD, reducing acute medication use and improving the MSQ scores, including, sometimes, reversion of chronic to episodic migraine (efficacy outcomes). Regarding the safety outcomes, the number and type of adverse events did not differ between anti-CGRP mAb-treated and placebo groups. CONCLUSIONS: Anti-CGRP or anti-CGRP receptor monoclonal antibodies are a promising preventive migraine therapy which can be particularly useful for resistant chronic migraine patients.


Subject(s)
Calcitonin Gene-Related Peptide , Migraine Disorders , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/therapeutic use , Calcitonin Gene-Related Peptide/therapeutic use , Humans , Migraine Disorders/chemically induced , Migraine Disorders/drug therapy , Migraine Disorders/prevention & control , Quality of Life , Treatment Outcome
8.
J Cell Physiol ; 237(4): 2107-2127, 2022 04.
Article in English | MEDLINE | ID: mdl-35243626

ABSTRACT

Breast cancer is the most common and deadliest type of cancer in women. Stress exposure has been associated with carcinogenesis and the stress released neurotransmitters, noradrenaline and adrenaline, and their cognate receptors, can participate in the carcinogenesis process, either by regulating tumor microenvironment or by promoting systemic changes. This work intends to provide an overview of the research done in this area and try to unravel the role of adrenergic ligands in the context of breast carcinogenesis. In the initiation phase, adrenergic signaling may favor neoplastic transformation of breast epithelial cells whereas, during cancer progression, may favor the metastatic potential of breast cancer cells. Additionally, adrenergic signaling can alter the function and activity of other cells present in the tumor microenvironment towards a protumor phenotype, namely macrophages, fibroblasts, and by altering adipocyte's function. Adrenergic signaling also promotes angiogenesis and lymphangiogenesis and, systemically, may induce the formation of preneoplastic niches, cancer-associated cachexia and alterations in the immune system which contribute for the loss of quality of life of breast cancer patients and their capacity to fight cancer. Most studies points to a major contribution of ß2 -adrenoceptor activated pathways on these effects. The current knowledge of the mechanistic pathways activated by ß2 -adrenoceptors in physiology and pathophysiology, the availability of selective drugs approved for clinical use and a deeper knowledge of the basic cellular and molecular pathways by which adrenergic stimulation may influence cancer initiation and progression, opens the possibility to use new therapeutic alternatives to improve efficacy of breast cancer treatments.


Subject(s)
Breast Neoplasms , Epinephrine/metabolism , Norepinephrine/metabolism , Stress, Physiological , Breast Neoplasms/pathology , Carcinogenesis , Female , Humans , Quality of Life , Receptors, Adrenergic, beta-2/metabolism , Signal Transduction , Tumor Microenvironment
9.
Int J Mol Sci ; 21(21)2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33120955

ABSTRACT

Adrenaline, which participates in the neuroendocrine response that occurs during stress and perimenopause, may be tumorigenic. This exploratory study aimed at investigating whether non-tumorigenic and tumorigenic human breast epithelial cell lines are able to synthesize adrenaline. The study was carried out in non-tumorigenic (MCF-10A) and tumorigenic (MCF-7) human breast cell lines. Expression of enzymes involved in adrenaline synthesis was characterized by RT-qPCR, immunocytochemistry and western blot. Catecholamines and analogue compounds were quantified by HPLC-ECD. Functional assessment of the impact of drugs on cells' tumorigenic potential was assessed by determination of cell viability and clonogenic ability. Both MCF-10A and MCF-7 cells produce catecholamines, but the capacity to produce adrenaline is lower in MCF-10A cells. ß-adrenoceptor activation increases the capacity of MCF-10A cells to produce adrenaline and favor both cell viability and colony formation. It is concluded that exposure of human breast epithelial cells to ß-adrenoceptor agonists increases cell proliferation and the capacity to produce adrenaline, creating an autocrine potential to spread these adrenergic effects in a feed-forward loop. It is conceivable that these effects are related to tumorigenesis, bringing a new perspective to understand the claimed anticancer effects of propranolol and the increase in breast cancer incidence caused by stress or during perimenopause.


Subject(s)
Adrenergic Agonists/pharmacology , Breast Neoplasms/metabolism , Breast/cytology , Catecholamines/biosynthesis , Receptors, Adrenergic/metabolism , Breast/drug effects , Breast/metabolism , Breast Neoplasms/genetics , Catecholamines/analysis , Cell Line , Cell Proliferation/drug effects , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Culture Media/analysis , Epinephrine/analysis , Epithelial Cells/cytology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Gene Expression Regulation/drug effects , Humans , MCF-7 Cells , Norepinephrine/analysis , Propranolol/pharmacology
10.
Eur J Pharmacol ; 885: 173504, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32858046

ABSTRACT

Leishmania infected macrophages have conditions to produce adenosine. Despite its known immunosuppressive effects, no studies have yet established whether adenosine alter Leishmania parasitic burden upon macrophage infection. This work aimed at investigating whether endogenous adenosine exerts an autocrine modulation of macrophage response towards Leishmania infection, identifying its origin and potential pharmacological targets for visceral leishmaniasis (VL), using THP-1 differentiated macrophages. Adenosine deaminase treatment of infected THP-1 cells reduced the parasitic burden (29.1 ± 2.2%, P < 0.05). Adenosine A2A and A2B receptor subtypes expression was confirmed by RT-qPCR and by immunocytochemistry and their blockade with selective adenosine A2A and A2B antagonists reduced the parasitic burden [14.5 ± 3.1% (P < 0.05) and 12.3 ± 3.1% (P < 0.05), respectively; and 24.9 ± 2.8% (P < 0.05), by the combination of the two antagonists)], suggesting that adenosine A2 receptors are tonically activated in infected THP-1 differentiated macrophages. The tonic activation of adenosine A2 receptors was dependent on the release of intracellular adenosine through equilibrative nucleoside transporters (ENT1/ENT2): NBTI or dipyridamole reduced (~25%) whereas, when ENTs were blocked, adenosine A2 receptor antagonists failed to reduce and A2 agonists increase parasitic burden. Effects of adenosine A2 receptors antagonists and ENT1/2 inhibitor were prevented by L-NAME, indicating that nitric oxide production inhibition prevents adenosine from increasing parasitic burden. Results suggest that intracellular adenosine, released through ENTs, elicits an autocrine increase in parasitic burden in THP-1 macrophages, through adenosine A2 receptors activation. These observations open the possibility to use well-established ENT inhibitors or adenosine A2 receptor antagonists as new therapeutic approaches in VL.


Subject(s)
Adenosine/metabolism , Autocrine Communication/drug effects , Leishmania infantum/drug effects , Leishmaniasis, Visceral/drug therapy , Macrophages/drug effects , Macrophages/parasitology , Receptor, Adenosine A2A/drug effects , Receptor, Adenosine A2B/drug effects , THP-1 Cells/drug effects , Adenosine A2 Receptor Antagonists/pharmacology , Body Burden , Equilibrative Nucleoside Transporter 1/drug effects , Equilibrative-Nucleoside Transporter 2/drug effects , Humans , Leishmaniasis, Visceral/parasitology , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide/biosynthesis , Nitric Oxide Synthase/antagonists & inhibitors
11.
Planta Med ; 86(2): 121-131, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31645066

ABSTRACT

Centaurium erythraea is a plant used in traditional medicine for several cardiovascular disorders, namely hypertension, but there is no scientific evidence able to provide a molecular basis for its claimed antihypertensive effects. After a preliminary screen of extracts obtained from sequential extraction of C. erythraea aerial parts, effects of the methanolic fraction (MFCE) on changes in perfusion pressure of isolated rat mesenteric vascular bed (MVB) and in rat cardiac fibroblasts proliferation were investigated, gathering information on the mechanisms involved in endothelium-dependent effects and their dependence on a pro-proliferative stimulus. The HPLC-DAD determination of the phenolics content of MFCE revealed the presence of 22 phenolic compounds. MFCE reduced (63.3 ± 3.9%; n = 4) perfusion pressure in MVB and almost completely abrogated the Ang II-induced increase in cardiac fibroblasts proliferation. Reduction of the perfusion pressure caused by MFCE was endothelium-dependent and occurred in parallel with an increase in NO release. These effects were inhibited by muscarinic receptor antagonists, by L-NAME (a NO synthase inhibitor), and by ODQ (a soluble guanylate cyclase inhibitor). Experiments revealed that effects required the involvement of K+ channels, being inhibited by tetraethylamonium (TEA; a Ca2+ activated K+ channels inhibitor) and by glibenclamide (an ATP-sensitive K+ channels inhibitor). In conclusion, extracts from C. erythraea, particularly the compounds present in the MFCE, induce endothelium-dependent vasodilation and prevent fibroblast proliferation induced by angiotensin II, which can account for the claimed antihypertensive effects of C. erythraea in traditional medicine.


Subject(s)
Antihypertensive Agents/pharmacology , Centaurium/chemistry , Plant Extracts/pharmacology , Animals , Antihypertensive Agents/isolation & purification , Cell Proliferation/drug effects , Cells, Cultured , Endothelium, Vascular/drug effects , Female , Fibroblasts/drug effects , Male , Plant Extracts/isolation & purification , Rats , Rats, Wistar , Vasodilator Agents/isolation & purification , Vasodilator Agents/pharmacology
12.
Biomolecules ; 9(9)2019 08 24.
Article in English | MEDLINE | ID: mdl-31450593

ABSTRACT

Carbidopa is used for the treatment of Parkinson's disease (PD) as an inhibitor of DOPA decarboxylase, and PD patients taking carbidopa have a lower incidence of various tumors, except for breast cancer and melanoma. Recently, it was shown that carbidopa inhibits tryptophan-2,3-dioxygenase (TDO) and kynureninase enzymes. In the present study, the effect of carbidopa on the viability and metabolic profile of breast cancer MCF-7 and melanoma A375 cells was investigated. Carbidopa was not effective in inhibiting MCF-7 and A375 proliferation. Liquid chromatography and mass spectrometry revealed a new compound, identified as indole-3-acetonitrile (IAN), which promoted a concentration-dependent increase in the viability of both cell lines. The results suggest that treatment with carbidopa may alter tryptophan (Trp) metabolism in breast cancer and melanoma leading to the formation of a pro-proliferative Trp metabolite, which may contribute to its failure in reducing breast cancers and melanoma incidence in PD patients taking carbidopa.


Subject(s)
Carbidopa/pharmacology , Cell Proliferation/drug effects , Indoles/metabolism , Tryptophan/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Female , Humans , Indoles/analysis , Melanoma/metabolism , Melanoma/pathology , Skin Neoplasms/metabolism , Skin Neoplasms/pathology , Spectrometry, Mass, Electrospray Ionization
13.
Molecules ; 23(9)2018 Sep 11.
Article in English | MEDLINE | ID: mdl-30208629

ABSTRACT

Although drugs currently used for the various types of diseases (e.g., antiparasitic, antiviral, antibacterial, etc.) are effective, they present several undesirable pharmacological and pharmaceutical properties. Most of the drugs have low bioavailability, lack of sensitivity, and do not target only the damaged cells, thus also affecting normal cells. Moreover, there is the risk of developing resistance against drugs upon chronic treatment. Consequently, their potential clinical applications might be limited and therefore, it is mandatory to find strategies that improve those properties of therapeutic agents. The development of prodrugs using amino acids as moieties has resulted in improvements in several properties, namely increased bioavailability, decreased toxicity of the parent drug, accurate delivery to target tissues or organs, and prevention of fast metabolism. Herein, we provide an overview of models currently in use of prodrug design with amino acids. Furthermore, we review the challenges related to the permeability of poorly absorbed drugs and transport and deliver on target organs.


Subject(s)
Amino Acids/chemistry , Prodrugs/chemical synthesis , Animals , Biological Availability , Drug Development , Humans , Prodrugs/chemistry , Prodrugs/pharmacokinetics
14.
Pharmacol Res Perspect ; 6(4): e00420, 2018 07.
Article in English | MEDLINE | ID: mdl-30156005

ABSTRACT

Vancomycin is a fundamental antibiotic in the management of severe Gram-positive infections. Inappropriate vancomycin dosing is associated with therapeutic failure, bacterial resistance and toxicity. Therapeutic drug monitoring (TDM) is acknowledged as an important part of the vancomycin therapy management, at least in specific patient subpopulations, but implementation in clinical practice has been difficult because there are no consensus and agglutinator documents. The aims of the present work are to present an overview of the current knowledge on vancomycin TDM and population pharmacokinetic (PPK) models relevant to specific patient subpopulations. Based on three published international guidelines (American, Japanese and Chinese) on vancomycin TDM and a bibliographic review on available PPK models for vancomycin in distinct subpopulations, an analysis of evidence was carried out and the current knowledge on this topic was summarized. The results of this work can be useful to redirect research efforts to address the detected knowledge gaps. Currently, TDM of vancomycin presents a moderate level of evidence and practical recommendations with great robustness in neonates, pediatric and patients with renal impairment. However, it is important to investigate in other subpopulations known to present altered vancomycin pharmacokinetics (eg neurosurgical, oncological and cystic fibrosis patients), where evidence is still unsufficient.


Subject(s)
Anti-Bacterial Agents/pharmacokinetics , Drug Monitoring , Models, Biological , Vancomycin/pharmacokinetics , Aged , Burns/metabolism , Child , Critical Illness , Hematologic Diseases/metabolism , Humans , Infant, Newborn , Neurosurgical Procedures , Obesity/metabolism , Renal Insufficiency/metabolism
15.
Article in English | MEDLINE | ID: mdl-29119938

ABSTRACT

BACKGROUND: Adenosine is a purine, with an adenine group and a ribose sugar, formed endogenously by ATP catabolism both intracellularly and extracellularly. Among the medicinal features of adenosine and its receptors (A1, A2A, A2B and A3), anticancer activity has been an intense field of research. The anticancer potential of adenosine receptor ligands has been brought to the forefront of research and evidenced in innumerous research articles and patents. OBJECTIVE: The present review focuses on the patent literature from 2002 onwards (2002-May 2017). METHODS: Patents were searched and downloaded from the open access patent data bases and are available online. RESULTS: A significant number of patents (65) have been published on adenosine receptor ligands claiming anticancer activity, or presenting new methods of preparation or treatment thereof, from 2002-2017 (May). From these, 35 were published highlighting the promising attributes of compounds/ methods to fight cancer. Most of the compounds act as adenosine A3 receptor agonists, while others act as antagonists for the other adenosine receptor subtypes. The signaling events triggered by activation of adenosine A3 receptor or by blockade of adenosine A1, A2A and A2B receptors can reverse an environment from being pro-cancer to an anti-cancer in the body. CONCLUSION: The promising anticancer effects mediated by adenosine receptor ligands put them in the forefront as new drug candidates. The present compilation can be worthy to medicinal chemists, pharmacologists, biochemists and other researchers focusing on the putative anticancer activity of adenosine receptor ligands.


Subject(s)
Antineoplastic Agents/metabolism , Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy , Neoplasms/metabolism , Patents as Topic , Receptors, Purinergic P1/metabolism , Animals , Clinical Trials as Topic/legislation & jurisprudence , Clinical Trials as Topic/methods , Humans , Ligands , Patents as Topic/legislation & jurisprudence , Purinergic P1 Receptor Agonists/metabolism , Purinergic P1 Receptor Agonists/therapeutic use , Purinergic P1 Receptor Antagonists/metabolism , Purinergic P1 Receptor Antagonists/therapeutic use
16.
Basic Clin Pharmacol Toxicol ; 118(6): 421-31, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26551921

ABSTRACT

Propofol is an anaesthetic widely used in both human beings and animals. However, the characterization of propofol pharmacokinetics (PK) is not well understood when long-term infusions are used. The main objective of this study was to explore the PK behaviour of propofol in a rabbit model during short and prolonged propofol infusions and to develop an internally validated PK model, for propofol dose individualization in the rabbit for future use. Population 1 (P1) was constituted by seven New Zealand rabbits and was used to characterize the PK profile of propofol at short infusions. Animals were anaesthetized with a bolus of 20 mg/kg, followed by an infusion rate of 50 mg/kg/hr of propofol at 1%, which was then maintained for 30 min. A second rabbit population (P2, n = 7) was sedated according to reflexes responses and Index of Consciousness values, for 20 consecutive hours using propofol 2% aiming at characterizing propofol behaviour at long-term infusions. Clinical data and blood samples were collected at specific time-points in both populations. Propofol plasma concentrations were determined by gas chromatography/ion trap mass spectrometry. The NONMEM VII software was used to evaluate the relationships between dose and plasma concentrations. A linear two-compartment model with different central compartment volume and plasma clearance (separately modelled in the two populations) was the one that best described propofol concentrations. The time course of propofol plasma concentrations was well characterized by the PK model developed, which simultaneously accounts for propofol short- and long-term infusions and can be used to optimize future PK studies in rabbits.


Subject(s)
Anesthetics, Intravenous/pharmacokinetics , Models, Biological , Propofol/pharmacokinetics , Anesthetics, Intravenous/administration & dosage , Animals , Dose-Response Relationship, Drug , Gas Chromatography-Mass Spectrometry , Infusions, Intravenous/methods , Male , Propofol/administration & dosage , Rabbits
17.
Biomed Res Int ; 2015: 217047, 2015.
Article in English | MEDLINE | ID: mdl-26539470

ABSTRACT

WHO reported that adherence among patients with chronic diseases averages only 50% in developed countries. This is recognized as a significant public health issue, since medication nonadherence leads to poor health outcomes and increased healthcare costs. Improving medication adherence is, therefore, crucial and revealed on many studies, suggesting interventions can improve medication adherence. One significant aspect of the strategies to improve medication adherence is to understand its magnitude. However, there is a lack of general guidance for researchers and healthcare professionals to choose the appropriate tools that can explore the extent of medication adherence and the reasons behind this problem in order to orchestrate subsequent interventions. This paper reviews both subjective and objective medication adherence measures, including direct measures, those involving secondary database analysis, electronic medication packaging (EMP) devices, pill count, and clinician assessments and self-report. Subjective measures generally provide explanations for patient's nonadherence whereas objective measures contribute to a more precise record of patient's medication-taking behavior. While choosing a suitable approach, researchers and healthcare professionals should balance the reliability and practicality, especially cost effectiveness, for their purpose. Meanwhile, because a perfect measure does not exist, a multimeasure approach seems to be the best solution currently.


Subject(s)
Chronic Disease/drug therapy , Health Care Costs , Medication Adherence , Chronic Disease/economics , Humans
18.
PLoS One ; 10(6): e0129224, 2015.
Article in English | MEDLINE | ID: mdl-26075386

ABSTRACT

Nitric oxide (NO) seems to contribute to vascular homeostasis regulating neurotransmission. This work aimed at assessing the influence of NO from different sources and respective intracellular pathways on sympathetic neurotransmission, in two vascular beds. Electrically-evoked [3H]-noradrenaline release was assessed in rat mesenteric and tail arteries in the presence of NO donors or endothelial/neuronal nitric oxide synthase (NOS) inhibitors. The influence of NO on adenosine-mediated effects was also studied using selective antagonists for adenosine receptors subtypes. Location of neuronal NOS (nNOS) was investigated by immunohistochemistry (with specific antibodies for nNOS and for Schwann cells) and Confocal Microscopy. Results indicated that: 1) in mesenteric arteries, noradrenaline release was reduced by NO donors and it was increased by nNOS inhibitors; the effect of NO donors was only abolished by the adenosine A1 receptors antagonist; 2) in tail arteries, noradrenaline release was increased by NO donors and it was reduced by eNOS inhibitors; adenosine receptors antagonists were devoid of effect; 3) confocal microscopy showed nNOS staining in adventitial cells, some co-localized with Schwann cells. nNOS staining and its co-localization with Schwann cells were significantly lower in tail compared to mesenteric arteries. In conclusion, in mesenteric arteries, nNOS, mainly located in Schwann cells, seems to be the main source of NO influencing perivascular sympathetic neurotransmission with an inhibitory effect, mediated by adenosine A1 receptors activation. Instead, in tail arteries endothelial NO seems to play a more relevant role and has a facilitatory effect, independent of adenosine receptors activation.


Subject(s)
Endothelium, Vascular/metabolism , Mesenteric Arteries/metabolism , Neurons/physiology , Nitric Oxide/metabolism , Synaptic Transmission/physiology , Adenosine A1 Receptor Antagonists/pharmacology , Adenosine Kinase/antagonists & inhibitors , Animals , Hemodynamics , Male , Mesenteric Arteries/drug effects , Nitric Oxide Synthase Type I/metabolism , Rats , Receptor, Adenosine A1/metabolism , Regional Blood Flow
19.
Int J Clin Pharm ; 37(2): 327-34, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25637404

ABSTRACT

BACKGROUND: An aging population and the increasing prevalence of chronic diseases have led to the increased use of medicines. Portugal is one of the European countries where more medicines are consumed and the associated expense is higher. Medicines are associated with enormous health benefits but also with the potential to cause illness and death. A drug related problem (DRP) is an "an event or circumstance involving drug therapy that actually or potentially interferes with desired health outcomes". In the U.S., they represent the 4th-6th leading cause of death and have an estimated cost of 130 billion dollars. Moreover, many of these DRP can be avoided. Elderly are at increased risk of DRP due to multiple factors: pluripathology and consequent polypharmacy, complex dosing regimens, pharmacokinetic/pharmacodynamic and functional/cognitive changes. Therefore, this population would be the one who would benefit most from the prevention, detection and control of DRP. The role of the pharmacist as an integral element of health care has been recognized by various international and European organizations. Providing pharmaceutical care as a patient-centered activity, focusing on their needs related to pharmacotherapy, contributes to guarantee that drug expenditure is a good investment, with benefits that outweigh potential risks. OBJECTIVE: To evaluate the need for pharmaceutical care implementation in institutionalized, polymedicated elderly. METHODS: Descriptive observational cross-sectional study carried out in six Portuguese nursing homes, selected by convenience, in November-December 2013. Each institution selected up to six patients, according to the following inclusion criteria: age ≥65 years, number of medications ≥5 and ability to respond to an interview. All participants signed an informed consent form. Pharmacists carried out a structured interview with each patient and consulted patient medical records to gather demographic data and information on health problems and medications used. To identify DRP, official drug information sources were consulted, and the STOPP and START tool was used. The ATC, the ICD-10 and the PCNE Classification V 6.2 classification systems were used for medicines, health problems and DRP classifications, respectively. For each medicine used, the cheapest equivalent available was also identified. RESULTS: The sample included 31 elderly (64.52 % female, mean age 81.65 ± 6.86). On average, subjects presented a mean of 7.94 ± 2.76 health problems with diseases of the circulatory system being the most common. The sample used a median of ten medicines per patient. Those medicines working in the cardiovascular, nervous and digestive systems were the most frequently used (29.75, 29.43 and 19.30 %, respectively). A total of 484 DRP (median: 15 DRP/patient) was found. The most common DRP were Adverse Drug Event, non-allergic (49.51 %), Drug treatment more costly than necessary (19.11 %), Effect of drug treatment not optimal (14.82 %) and Unnecessary drug treatment (6.16 %). The most cost-effective proposal, would lead to a saving of 3,950/year in the studied sample. CONCLUSION: These results reinforce the need for the implementation of pharmaceutical care services to institutionalized elderly, necessary to improve medicines efficacy and safety, better clinical outcomes and cost reduction.


Subject(s)
Drug-Related Side Effects and Adverse Reactions/prevention & control , Institutionalization/methods , Pharmaceutical Services , Pharmacists , Polypharmacy , Professional Role , Aged , Aged, 80 and over , Cross-Sectional Studies , Drug-Related Side Effects and Adverse Reactions/epidemiology , Female , Homes for the Aged/standards , Humans , Institutionalization/standards , Male , Nursing Homes/standards , Pharmaceutical Services/standards , Pharmacists/standards
20.
Neurochem Int ; 80: 7-13, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25447765

ABSTRACT

The present study intends to clarify if endothelium dysfunction impairs vascular sympathetic neurotransmission. Electrically-evoked tritium overflow (100 pulses/5 Hz) was evaluated in arteries (intact and denuded) or exhibiting some degree of endothelium dysfunction (spontaneously hypertensive arteries), pre-incubated with [(3)H]-noradrenaline in the presence of enzymes (nitric oxide synthase (NOS); nicotinamide adenine dinucleotide phosphate (NADPH) oxidase; xanthine oxidase; cyclooxygenase; adenosine kinase) inhibitors and a nucleoside transporter inhibitor. Inhibition of endothelial nitric oxide synthase with L-NIO dihydrochloride reduced tritium overflow in intact arteries whereas inhibition of neuronal nitric oxide synthase with Nω-Propyl-L-arginine hydrochloride was devoid of effect showing that only endothelial nitric oxide synthase is involved in vascular sympathetic neuromodulation. Inhibition of enzymes involved in reactive oxygen species or prostaglandins production with apocynin and allopurinol or indomethacin, respectively, failed to alter tritium overflow. A facilitation or reduction of tritium overflow was observed in the presence of 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) or of 5-iodotubericidin, respectively, but only in intact arteries. These effects can be ascribed to a tonic inhibitory effect mediated by A1 receptors. In denuded and hypertensive arteries, 7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c] pyrimidine (SCH 58261) reduced tritium overflow, suggesting the occurrence of a tonic activation of A2A receptors. When endogenous adenosine bioavailability was increased by the nucleoside transporter inhibitor, S-(4-Nitrobenzyl)-6-thioinosine, tritium overflow increased in intact, denuded and hypertensive arteries. Among the endothelium-derived substances studied that could alter vascular sympathetic transmission only adenosine/adenosine receptor mediated mechanisms were clearly impaired by endothelium injury/dysfunction.


Subject(s)
Adenosine/metabolism , Arteries/metabolism , Endothelium, Vascular/metabolism , Norepinephrine/metabolism , Tail/blood supply , Tail/metabolism , Animals , Arteries/physiopathology , Endothelium, Vascular/physiopathology , Male , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Reactive Oxygen Species/metabolism , Synaptic Transmission/physiology
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