RESUMO
Highly sulfated malto-oligomers, similar to heparin and heparan-sulfate, have good antiviral, antimetastatic, anti-inflammatory and cell growth inhibitory effects. Due to their broad biological activities and simple structure, sulfated malto-oligomer derivatives have a great therapeutic potential, therefore, the development of efficient synthesis methods for their production is of utmost importance. In this work, preparation of α-(1â4)-linked oligoglucosides containing a sulfonatomethyl moiety at position C-6 of each glucose unit was studied by different approaches. Malto-oligomeric sulfonic acid derivatives up to dodecasaccharides were prepared by polymerization using different protecting groups, and the composition of the product mixtures was analyzed by MALDI-MS methods and size-exclusion chromatography. Synthesis of lower oligomers was also accomplished by stepwise and block synthetic methods, and then the oligosaccharide products were persulfated. The antiviral, anti-inflammatory and cell growth inhibitory activity of the fully sulfated malto-oligosaccharide sulfonic acids were determined by in vitro tests. Four tested di- and trisaccharide sulfonic acids effectively inhibited the activation of the TNF-α-mediated inflammatory pathway without showing cytotoxicity.
Assuntos
Oligossacarídeos , Sulfatos , Polimerização , Oligossacarídeos/farmacologia , Ácidos Sulfônicos , Anti-Inflamatórios/farmacologia , Antivirais/farmacologiaRESUMO
Doxorubicin (DOX) is an efficacious and commonly used chemotherapeutic agent. However, its clinical use is limited due to dose-dependent cardiotoxicity. Several mechanisms have been proposed to play a role in DOX-induced cardiotoxicity, such as free radical generation, oxidative stress, mitochondrial dysfunction, altered apoptosis, and autophagy dysregulation. BGP-15 has a wide range of cytoprotective effects, including mitochondrial protection, but up to now, there is no information about any of its beneficial effects on DOX-induced cardiotoxicity. In this study, we investigated whether the protective effects of BGP-15 pretreatment are predominantly via preserving mitochondrial function, reducing mitochondrial ROS production, and if it has an influence on autophagy processes. H9c2 cardiomyocytes were pretreated with 50 µM of BGP-15 prior to different concentrations (0.1; 1; 3 µM) of DOX exposure. We found that BGP-15 pretreatment significantly improved the cell viability after 12 and 24 h DOX exposure. BGP-15 ameliorated lactate dehydrogenase (LDH) release and cell apoptosis induced by DOX. Additionally, BGP-15 pretreatment attenuated the level of mitochondrial oxidative stress and the loss of mitochondrial membrane potential. Moreover, BGP-15 further slightly modulated the autophagic flux, which was measurably decreased by DOX treatment. Hence, our findings clearly revealed that BGP-15 might be a promising agent for alleviating the cardiotoxicity of DOX. This critical mechanism appears to be given by the protective effect of BGP-15 on mitochondria.
Assuntos
Cardiotoxicidade , Doxorrubicina , Humanos , Cardiotoxicidade/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Doxorrubicina/toxicidade , Estresse Oxidativo , Miócitos Cardíacos/metabolismo , Mitocôndrias/metabolismo , Apoptose , Antibióticos Antineoplásicos/toxicidadeRESUMO
Nasal drug delivery has been a focus of scientific interest for decades. A number of drug delivery systems and devices are available and have been highly successful in providing better and more comfortable therapy. The benefits of nasal drug delivery are not in question. The nasal surface provides an excellent context for the targeted delivery of active substances. In addition to the large nasal surface area and intensive absorption, the active substances delivered through the nose overcome the blood-brain barrier and can be delivered directly to the central nervous system. Formulations for nasal administration are typically solutions or liquid dispersed systems such as emulsions or suspensions. Formulation techniques for nanostructures have recently undergone intensive development. Solid-phase heterogeneous dispersed systems represent a new direction in pharmaceutical formulations. The wide range of possible examples and the variety of excipients allow for the delivery of a wide range of active ingredients. The aim of our experimental work was to develop a solid drug delivery system that possesses all of the above-mentioned advantageous properties. In developing solid nanosystems, we not only exploited the advantages of size but also the adhesive and penetration-enhancing properties of excipients. During formulation, several amphiphilic compounds with adhesion properties and penetration enhancing effects were incorporated. We used chlorpromazine (CPZ), which is mainly used in the treatment of psychotic disorders such as schizophrenia and bipolar disorder. Chlorpromazine has been previously investigated by our team in other projects. With the availability of previous methods, the analytical characterization of the drug was carried out effectively. Due to the frequent and severe side effects of the drug, the need for therapeutic dose reduction is indisputable. In this series of experiments, we succeeded in constructing drug delivery systems. Finely divided Na nanoparticles were formed using a Büchi B90 nanospray dryer. An important step in the development of the drug carrier was the selection of suitable inert carrier compounds. Particle size determination and particle size distribution analysis were performed to characterize the prepared nanostructures. As safety is the most important aspect of any drug formulation, all components and systems were tested with different biocompatibility assays. The tests performed demonstrated the safe applicability of our systems. The bioavailability of chlorpromazine was studied as a function of the ratio of the active ingredient administered nasally and intravenously. As described above, most nasal formulations are liquids, but our system is solid, so there is currently no tool available to accurately target this system. As a supplement of the project, a nasal dosing device was developed, corresponding to the anatomical structure; a prototype of the device was made using 3D FDM technology. Our results lay the foundation for the design and industrial scaling of a new approach to the design and production of a high-bioavailability nasal medicinal product.
Assuntos
Clorpromazina , Nanopartículas , Excipientes/química , Administração Intranasal , Sistemas de Liberação de Medicamentos/métodos , Portadores de Fármacos/química , Nanopartículas/química , Tamanho da PartículaRESUMO
Beta-carotene (BC) is a well-known antioxidant. However, increasing evidence shows that under severe oxidative conditions, BC can become pro-oxidant, an effect that may be enhanced in the presence of iron (II). In our earlier studies, we observed that despite increasing heme oxygenase-1 (HO-1) levels in the heart, the protective effects of BC have been lost when it was used at a high concentration. Since iron releases from heme as a consequence of HO-1 activity, we hypothesized that the application of an iron-chelator (IC) would reverse the lost cardiac protection associated with an elevated HO-1 level. Thus, in the present study, we investigated the effects of desferrioxiamine (DFO) in isolated, ischemic/reperfused rat hearts after long-term treatment with vehicle or high-dose (HD) BC. Vehicle or 150 mg/bw kg daily doses of BC were administered to the rats for 4 weeks, and then their hearts were removed and subjected to 30 min of global ischemia (ISA) followed by 120 min of reperfusion (REP). During the experiments, cardiac function was registered, and at the end of the REP period, infarct size (IS) and HO-1 expression were measured. The results show that DFO treatment alone during REP significantly ameliorated postischemic cardiac function and decreased IS, although HO-1 expression was not increased significantly. In hearts isolated from BC-treated rats, no cardioprotective effects, despite an elevated HO-1 level, were observed, while DFO administration after ISA resulted in a mild improvement in heart function and IS. Our results suggest that iron could have a role whether BC exerts antioxidant or pro-oxidant effects in ISA/REP-injured hearts.
Assuntos
Heme Oxigenase-1 , Traumatismo por Reperfusão Miocárdica , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase-1/metabolismo , Ferro/metabolismo , Isquemia/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , beta Caroteno/metabolismo , beta Caroteno/farmacologiaRESUMO
Turmeric has been used for decades for its antioxidant and anti-inflammatory effect, which is due to an active ingredient isolated from the plant, called curcumin. However, the extremely poor water-solubility of curcumin often limits the bioavailability of the drug. The aim of our experimental work was to improve the solubility and thus bioavailability of curcumin by developing self-nano/microemulsifying drug delivery systems (SN/MEDDS). Labrasol and Cremophor RH 40 as nonionic surfactants, Transcutol P as co-surfactant and isopropyl myristate as the oily phase were used during the formulation. The average droplet size of SN/MEDDS containing curcumin was between 32 and 405 nm. It was found that the higher oil content resulted in larger particle size. The drug loading efficiency was between 93.11% and 99.12% and all formulations were thermodynamically stable. The curcumin release was studied at pH 6.8, and the release efficiency ranged between 57.3% and 80.9% after 180 min. The results of the MTT cytotoxicity assay on human keratinocyte cells (HaCaT) and colorectal adenocarcinoma cells (Caco-2) showed that the curcumin-containing preparations were non-cytotoxic at 5 w/v%. According to the results of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide dismutase (SOD) assays, SNEDDS showed significantly higher antioxidant activity. The anti-inflammatory effect of the SN/MEDDS was screened by enzyme-linked immunosorbent assay (ELISA). SNEDDS formulated with Labrasol as surfactant, reduced tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) levels below 60% at a concentration of 10 w/w%. Our results verified the promising use of SN/MEDDS for the delivery of curcumin. This study demonstrates that the SN/MEDDS could be promising alternatives for the formulation of poorly soluble lipophilic compounds with low bioavailability.
Assuntos
Curcumina , Administração Oral , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Disponibilidade Biológica , Células CACO-2 , Curcumina/química , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Excipientes , Humanos , Interleucina-1beta , Óleos/química , Tamanho da Partícula , Solubilidade , Superóxido Dismutase , Tensoativos/química , Fator de Necrose Tumoral alfa , ÁguaRESUMO
BACKGROUND: Cardioprotective effects of H2S are being suggested by numerous studies. Furthermore, H2S plays a role in relaxation of vascular smooth muscle, protects against oxidative stress, and modulates inflammation. Long-term high-dose use of NSAIDs, such as ibuprofen, have been associated with enhanced cardiovascular risk. The goal of the present work is the synthesis and basic pharmacological characterization of a newly designed H2S-releasing ibuprofen derivative. METHODS: Following the synthesis of EV-34, a new H2S-releasing derivative of ibuprofen, oxidative stability assays were performed (Fenton and porphyrin assays). Furthermore, stability of the molecule was studied in rat serum and liver lysates. H2S-releasing ability of the EC-34 was studied with a hydrogen sulfide sensor. MTT (3-(4,5-dimethylthiazol 2-yl)-2,5-(diphenyltetrazolium bromide)) assay was carried out to monitor the possible cytotoxic effect of the compound. Cyclooxygenase (COX) inhibitory property of EV-34 was also evaluated. Carrageenan assay was carried out to compare the anti-inflammatory effect of EV-34 to ibuprofen in rat paws. RESULTS: The results revealed that the molecule is stable under oxidative condition of Fenton reaction. However, EV-34 undergoes biodegradation in rat serum and liver lysates. In cell culture medium H2S is being released from EV-34. No cytotoxic effect was observed at concentrations of 10, 100, 500 µM. The COX-1 and COX-2 inhibitory effects of the molecule are comparable to those of ibuprofen. Furthermore, based on the carrageenan assay, EV-34 exhibits the same anti-inflammatory effect to that of equimolar amount of ibuprofen (100 mg/bwkg). CONCLUSION: The results indicate that EV-34 is a safe H2S releasing ibuprofen derivative bearing anti-inflammatory properties.
Assuntos
Sulfeto de Hidrogênio/química , Ibuprofeno/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Ibuprofeno/farmacologia , Inflamação/tratamento farmacológico , Masculino , Estresse Oxidativo/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Cardiomyopathy is a common side effect of doxorubicin (DOX) chemotherapy. Despite intensive research efforts in the field, there is still no evidence available for routine cardioprotective prophylaxis to prevent cardiotoxicity in the majority of oncological patients at low risk of cardiovascular disease. We have recently demonstrated the advantages of a prophylactic, combined heart failure therapy in an experimental model of DOX-induced cardiomyopathy. In the current work, we focus on individually applied prophylactic medications studied in the same translational environment to clarify their distinct roles in the prevention of DOX cardiotoxicity. METHODS: Twelve-week-old male Wistar rats were divided into 5 subgroups. Prophylactic ß-blocker (BB, bisoprolol), angiotensin-converting enzyme inhibitor (ACEI, perindopril) or aldosterone antagonist (AA, eplerenone) treatments were applied 1 week before DOX administration, then 6 cycles of intravenous DOX chemotherapy were administered. Rats receiving only intravenous DOX or saline served as positive and negative controls. Blood pressure, heart rate, body weight, and echocardiographic parameters were monitored in vivo. Two months after the last DOX administration, the animals were sacrificed, and their heart and serum samples were frozen in liquid nitrogen for histological, mechanical, and biochemical measurements. RESULTS: All prophylactic treatments increased the survival of DOX-receiving animals. The lowest mortality rates were seen in the BB and ACEI groups. The left ventricular ejection fraction was only preserved in the BB group. The DOX-induced increase in the isovolumetric relaxation time could not be prevented by any prophylactic treatment. A decreased number of apoptotic nuclei and a preserved myocardial ultrastructure were found in all groups receiving prophylactic cardioprotection, while the DOX-induced fibrotic remodelling and the increase in caspase-3 levels could only be substantially prevented by the BB and ACEI treatments. CONCLUSION: Primary prophylaxis with cardioprotective agents like BB or ACEI has a key role in the prevention of DOX-induced cardiotoxicity in healthy rats. Future human studies are necessary to implement this finding in the clinical management of oncological patients free of cardiovascular risk factors.
Assuntos
Cardiomiopatias , Preparações Farmacêuticas , Animais , Doxorrubicina/efeitos adversos , Humanos , Masculino , Ratos , Ratos Wistar , Volume Sistólico , Função Ventricular EsquerdaRESUMO
Several groups have demonstrated that induction of heme-oxygenase-1 (HO-1) could protect the myocardium against ischemic events; however, heme accumulation could lead to toxicity. The aim of the present study was to investigate the role of autophagy in heme toxicity. H9c2 cardiomyoblast cells were treated with different dose of hemin or cobalt-protoporphyrin IX (CoPPIX) or vehicle. Cell viability was measured by MTT assay. DCF and MitoSOX staining was employed to detect reactive oxygen species. Western blot analysis was performed to analyse the levels of HO-1, certain autophagy related proteins and pro-caspase-3 as an apoptosis marker. To study the autophagic flux, CytoID staining was carried out and cells were analyzed by fluorescence microscope and flow cytometry. Decreased cell viability was detected at high dose of hemin and CoPPIX treated H9c2 cells in a dose-dependent manner. Furthermore, at concentration of the inducers used in the present study a significantly enhanced level of ROS were detected. As it was expected both treatments induced a robust elevation of HO-1 level. In addition, the Beclin-1- independent autophagy was significantly increased, but caused a defective autophagic flux with triggered activation of caspase-3. In conclusion, these results suggest that overexpression of HO-1 by high dose of hemin and CoPPIX can induce cell toxicity in H9c2 cells via enhanced ROS level and impaired autophagy.
Assuntos
Autofagia , Heme Oxigenase-1/metabolismo , Hemina/metabolismo , Mioblastos Cardíacos/citologia , Protoporfirinas/metabolismo , Animais , Sobrevivência Celular , Mioblastos Cardíacos/metabolismo , Estresse Oxidativo , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Chemotherapy-induced left ventricular dysfunction represents a major clinical problem, which is often only recognised at an advanced stage, when supportive therapy is ineffective. Although an early heart failure treatment could positively influence the health status and clinical outcome, there is still no evidence of routine prophylactic cardioprotection for the majority of patients without previous cardiovascular history awaiting potentially cardiotoxic chemotherapy. In this study, we set out to investigate whether a prophylactic cardioprotective therapy relative to a conventionally scheduled heart failure treatment is more effective in preventing cardiotoxicity in a rodent model of doxorubicin (DOX)-induced cardiomyopathy. METHODS: Male Wistar rats (n = 7-11 per group) were divided into 4 subgroups, namely negative controls receiving intravenous saline (CON), positive controls receiving intravenous DOX (6 cycles; D-CON), and DOX-treated animals receiving either prophylactic (PRE, started 1 week before DOX) or conventionally applied (POST, started 1 month after DOX) combined heart failure therapy of oral bisoprolol, perindopril and eplerenone. Blood pressure, heart rate, body weight and echocardiographic parameters were monitored in vivo, whereas myocardial fibrosis, capillarisation, ultrastructure, myofilament function, apoptosis, oxidative stress and mitochondrial biogenesis were studied in vitro. RESULTS: The survival rate in the PRE group was significantly improved compared to D-CON (p = 0.0207). DOX increased the heart rate of the animals (p = 0.0193), while the blood pressure (p ≤ 0.0105) and heart rate (p = 0.0029) were significantly reduced in the PRE group compared to D-CON and POST. The ejection fraction remained preserved in the PRE group compared to D-CON or POST (p ≤ 0.0237), while none of the treatments could prevent the DOX-induced increase in the isovolumetric relaxation time. DOX decreased the rate of the actin-myosin cross-bridge cycle, irrespective of any treatment applied (p ≤ 0.0433). The myocardium of the D-CON and POST animals displayed pronounced ultrastructural damage, which was not apparent in the PRE group (p ≤ 0.033). While the DOX-induced apoptotic activity could be reduced in both the PRE and POST groups (p ≤ 0.0433), no treatment was able to prevent fibrotic remodelling or the disturbed mitochondrial biogenesis. CONCLUSION: For attenuating DOX-induced adverse myocardial effects, prophylactic cardioprotection has many advantages compared to a late-applied treatment.
Assuntos
Cardiomiopatias/induzido quimicamente , Cardiomiopatias/terapia , Doxorrubicina/efeitos adversos , Insuficiência Cardíaca/terapia , Animais , Apoptose , Cardiomiopatias/diagnóstico por imagem , Caspase 3/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Fibrose , Insuficiência Cardíaca/diagnóstico por imagem , Masculino , Miocárdio/patologia , Miocárdio/ultraestrutura , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos Wistar , Análise de SobrevidaRESUMO
BACKGROUND: The pathological heart contractions, called arrhythmias, especially ventricular fibrillation (VF), are a prominent feature of many cardiovascular diseases leading to sudden cardiac death. The present investigation evaluates the effect of electrically stimulated VF on cardiac functions related to autophagy and apoptotic mechanisms in isolated working rat hearts. METHODS: Each group of hearts was subjected to 0 (Control), 1, 3, or 10 min of spacing-induced VF, followed by 120 min of recovery period and evaluated for cardiac functions, including aortic flow (AF), coronary flow (CF), cardiac output (CO), stroke volume (SV), and heart rate (HR). Hearts were also evaluated for VF effects on infarcted zone magnitude and Western blot analysis was conducted on heart tissue for expression of the apoptotic biomarker cleaved-caspase-3 and the autophagy proteins: p62, P-mTOR/mTOR, LC3BII/LC3BI ratio, and Atg5-12 complexes. RESULTS: Data revealed that VF induced degradation in AF, CF, CO, and SV, which prominently included-variable post-VF capacity for recovery of normal heart rhythm; increased extent of infarcted heart tissue; altered expression of cleaved-caspase-3 suggesting potential for VF-mediated amplification of apoptosis. VF influence on expression of p62, LC3BII/LC3BI, and Atg5-12 proteins was complex, possibly due to differential effects of VF-induced expression on proteins comprising the autophagic program. CONCLUSIONS: VF was observed to cause time-dependent changes in autophagy processes, which with additional analysis under ongoing investigations, likely to yield novel therapeutic targets for the prevention of VF and sudden cardiac death.
Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Sistema Cardiovascular/patologia , Miocárdio/patologia , Fibrilação Ventricular/patologia , Fibrilação Ventricular/fisiopatologia , Animais , Estimulação Cardíaca Artificial , Sistema Cardiovascular/fisiopatologia , Caspase 3/metabolismo , Masculino , Ratos Sprague-DawleyRESUMO
Nowadays, there is a growing interest in compounds derived from plants as potential raw materials for drug development. One of the most studied compounds is beta-carotene (BC). Several clinical studies can be found investigating the cardiovascular effects of BC, however, all these results are controversial. There is an increasing body of evidence showing that besides the well-known antioxidant properties, under strong oxidative circumstances, BC could become prooxidant as well. In this study, we investigated the effects of long-term, low- and high-dose BC treatment in ischemic/reperfused (ISA/REP) hearts isolated from Zucker diabetic fatty (ZDF) rats. The animals were treated with various daily doses of BC for 4 weeks and then hearts were isolated and subjected to 30 min of global ischemia (ISA) followed by 120 min of reperfusion (REP). Blood glucose levels were measured before, after two weeks, and at the end of the treatment. In isolated hearts, the myocardial function was registered. At the end of the reperfusion period, the infarct size (IS) and heme oxygenase-1 (HO-1) expression were measured. The results showed that a low dose of BC treatment significantly improved postischemic recovery, which was reflected in a decreased IS. Interestingly, when BC was applied at high concentrations, the observed protective effects were lost. Although BC treatment increased HO-1 expression, we did not observe a better heart function and/or decreased IS in the high-dose-treated group. Glucose tolerance tests showed a concentration-independent decrease in blood glucose levels. Our results suggest that long-term, low-dose BC treatment could be effective in the treatment of type-2-diabetes and related cardiovascular diseases.
Assuntos
Antioxidantes/uso terapêutico , Cardiomiopatias Diabéticas/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Isquemia Miocárdica/tratamento farmacológico , beta Caroteno/uso terapêutico , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Glicemia/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Coração/efeitos dos fármacos , Masculino , Isquemia Miocárdica/etiologia , Miocárdio/metabolismo , Miocárdio/patologia , Ratos , Ratos Zucker , beta Caroteno/administração & dosagem , beta Caroteno/farmacologiaRESUMO
Recent evidence from studies suggests that aged black garlic also has an effect on health. The major aim of the present study is to compare the effect of raw and aged black garlic on postischemic cardiac recovery. Male Sprague Dawley rats were randomly divided into three groups. Animals of the first group were fed with raw garlic, animals of the second group received aged black garlic, while the third group served as vehicle-treated controls. Upon conclusion of the treatment, isolated hearts were undertaken to ischemia/reperfusion. Heart function and infarct size were measured and the level of HO-1 and iNOS were studied. Superior postischemic cardiac function and reduced infarct size in both garlic treated groups compared to the drug-free control group, indicated cardioprotective effects. However, no significant differences between the garlic treated groups were observed. Western blot analysis revealed that raw garlic enhanced the level of HO-1 before ischemia, while in ischemic samples, we found elevated HO-1 expression in both garlic treated groups. The level of iNOS was the same before ischemia in all groups, however, a markedly reduced iNOS level in ischemic/reperfused hearts originating from control and raw garlic treated animals was observed. Samples from aged black garlic treated animals demonstrated that the level of iNOS was not significantly reduced after ischemia/reperfusion. Taken together these results indicate that not only raw but also aged black garlic possess a cardioprotective effect.
Assuntos
Alho , Heme Oxigenase (Desciclizante)/metabolismo , Traumatismo por Reperfusão Miocárdica/dietoterapia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Ratos , Ratos Sprague-DawleyRESUMO
The molecular mechanisms underlying doxorubicin-induced cardiotoxicity are still being investigated, but are known to involve oxidative stress, mitochondrial dysfunction, and the dysregulation of autophagy. The objective of the current study was to examine the protective role of metformin and its effect on autophagy in doxorubicin-induced cardiotoxicity. Spragueâ»Dawley rats were divided into four groups at random. The doxorubicin-treated group received doxorubicin (3 mg/kg every second day) intraperitoneally. The metformin-treated group received 250 mg/kg/day metformin via gavage. The doxorubicin + metformin-treated group received both at the above-mentioned doses. The control group received vehicle only. Following the two-week treatment, the hearts were isolated, and cardiac functions were registered. Serum levels of lactate dehydrogenase (LDH), creatine kinase iso-enzyme MB (CK-MB) enzyme, Troponin T, and cardiac malondialdehyde (MDA) were also measured. Heart tissue samples were histopathologically examined by using Masson's trichrome staining and Western blot analysis was conducted for evaluating the expression level of AMP-activated protein kinase (AMPK) and autophagy-associated proteins beclin-1, LC3B-II, and p62, respectively. The results revealed that treatment with metformin conferred increased cardiac protection against the development of cardiotoxicity manifested by a significant decrease in serum Troponin T and cardiac MDA levels, and remarkable improvement in heart function in connection with histopathological features. Furthermore, by focusing on the contribution of autophagic proteins, it was found that metformin normalised autophagy, which may help cardiomyocytes survive doxorubicin-induced toxicity. These results promote the use of metformin, which would be a preferable drug for patients receiving doxorubicin.
Assuntos
Autofagia/efeitos dos fármacos , Cardiotônicos/farmacologia , Cardiotoxicidade/etiologia , Doxorrubicina/efeitos adversos , Metformina/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Animais , Biomarcadores , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Células Cultivadas , Feminino , Testes de Função Cardíaca , Peroxidação de Lipídeos/efeitos dos fármacos , Miocárdio/metabolismo , Miocárdio/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
Oxidative stress placed on tissues that involved in pathogenesis of a disease activates compensatory metabolic changes, such as DNA damage repair that in turn causes intracellular accumulation of detritus and 'proteotoxic stress', leading to emergence of 'senescent' cellular phenotypes, which express high levels of inflammatory mediators, resulting in degradation of tissue function. Proteotoxic stress resulting from hyperactive inflammation following reperfusion of ischaemic tissue causes accumulation of proteinaceous debris in cells of the heart in ways that cause potentially fatal arrhythmias, in particular ventricular fibrillation (VF). An adaptive response to VF is occurrence of autophagy, an intracellular bulk degradation of damaged macromolecules and organelles that may restore cellular and tissue homoeostasis, improving chances for recovery. Nevertheless, depending on the type and intensity of stressors and inflammatory responses, autophagy may become pathological, resulting in excessive cell death. The present review examines the multilayered defences that cells have evolved to reduce proteotoxic stress by degradation of potentially toxic material beginning with endoplasmic reticulum-associated degradation, and the unfolded protein response, which are mechanisms for removal from the endoplasmic reticulum of misfolded proteins, and then progressing through the stages of autophagy, including descriptions of autophagosomes and related vesicular structures which process material for degradation and autophagy-associated proteins including Beclin-1 and regulatory complexes. The physiological roles of each mode of proteotoxic defence will be examined along with consideration of how emerging understanding of autophagy, along with a newly discovered regulatory cell type called telocytes, may be used to augment existing strategies for the prevention and management of cardiovascular disease.
Assuntos
Arritmias Cardíacas/genética , Autofagia/genética , Estresse Oxidativo/genética , Fibrilação Ventricular/genética , Arritmias Cardíacas/fisiopatologia , Senescência Celular/genética , Degradação Associada com o Retículo Endoplasmático/genética , Humanos , Isquemia Miocárdica/genética , Isquemia Miocárdica/fisiopatologia , Complexo de Endopeptidases do Proteassoma/genética , Resposta a Proteínas não Dobradas/genética , Fibrilação Ventricular/fisiopatologiaRESUMO
Objective: A rat model is here used to test a hypothesis that Momordica charantia (Bitter melon (BM)) extract favorably alters processes in cardiovascular tissue and is systemically relevant to the pathophysiology of type 2 diabetes (T2DM) and related cardiovascular disease. Methods: Male Lean and Zucker Obese (ZO) rats were gavage-treated for six weeks with 400 mg/kg body weight bitter melon (BM) extract suspended in mucin-water vehicle, or with vehicle (Control). Animals were segregated into four treatment groups, 10 animals in each group, according to strain (Lean or ZO) and treatment (Control or BM). Following six-week treatment periods, peripheral blood was collected from selected animals, followed by sacrifice, thoracotomy and mounting of isolated working heart setup. Results: Body mass of both Lean and ZO rats was unaffected by treatment, likewise, peripheral blood fasting glucose levels showed no significant treatment-related effects. However, some BM treatment-related improvement was noted in postischemic cardiac functions when Lean, BM-treated animals were compared to vehicle treated Lean control rats. Treatment of Lean, but not ZO, rats significantly reduced the magnitude of infarcted zone in isolated hearts subjected to 30 min of ischemia followed by 2 h of working mode reperfusion. Immunohistochemical demonstration of caspase-3 expression by isolated heart tissues subjected to 30 min of ischemia followed by 2 h of reperfusion, revealed significant correlation between BM treatment and reduced expression of this enzyme in hearts obtained from both Lean and ZO animals. The hierarchy and order of caspase-3 expression from highest to lowest was as follows: ZO rats receiving vehicle > ZO rats receiving BM extract > Lean rats treated receiving vehicle > Lean rats administered BM extract. Outcomes of analyses of peripheral blood content of cardiac-related analytics: with particular relevance to clinical application was a significant elevation in blood of ZO and ZO BM-treated, versus Lean rats of total cholesterol (high density lipoprotein HDL-c + low density lipoprotein LDL-c), with an inferred increase in HDL-c/LDL-c ratio-an outcome associated with decreased risk of atherosclerotic disease. Conclusions: BM extract failed to positively affect T2DM- and cardiovascular-related outcomes at a level suggesting use as a standalone treatment. Nevertheless, the encouraging effects of BM in enhancement of cardiac function, suppression of post-ischemic/reperfused infarct size extent and capacity to modulate serum cholesterol, will likely make it useful as an adjuvant therapy for the management of T2DM and related cardiovascular diseases.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Momordica charantia/química , Isquemia Miocárdica/fisiopatologia , Obesidade/complicações , Extratos Vegetais/administração & dosagem , Animais , Caspase 3/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Esquema de Medicação , Regulação da Expressão Gênica/efeitos dos fármacos , Testes de Função Cardíaca/efeitos dos fármacos , Masculino , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/metabolismo , Obesidade/metabolismo , Extratos Vegetais/farmacologia , Ratos , Ratos ZuckerRESUMO
Nowadays, there is an increase in the application of natural products for the prevention of different disorders or adjuvant substances next to pharmacological treatment. Phytochemicals include different chromone derivatives, which possess a wide spectrum of biological activity. The aim of the present study was the investigation of the antioxidant activity, cytotoxicity and oxidative transformation of nine chromone derivatives. First, we investigated the radical scavenging activity (ABTS), the oxygen radical absorption capacity (ORAC) and the ferric reducing antioxidant power (FRAP) of the investigated molecules. The cytotoxic effects of the compounds were tested on H9c2 cell cultures by the MTT assay. Each compound showed a significant ORAC value compared to the reference. However, the compound 865 possess significantly higher FRAP and ABTS activity in comparison with the reference and other tested molecules, respectively. Based on these assays, the compound 865 was selected for further analysis. In these experiments, we investigated the oxidative metabolism of the compound in vitro. The molecule was oxidized by the Fenton reaction, artificial porphyrin and electrochemistry; then, the formed products were identified by mass spectrometry. Four possible metabolites were detected. The results revealed the compound 865 to possess good antioxidant properties and to be stable metabolically; hence, it is worth investigating its effects in vivo.
Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Cromonas/química , Cromonas/farmacologia , Oxirredução/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular , Eletroquímica , Humanos , Espectrometria de Massas , Compostos Fitoquímicos/químicaRESUMO
ß-carotene (BC), a lipid-soluble tetraterpene precursor to vitamin A, widely distributed in plants, including many used in human diet, has well-known health-enhancing properties, including reducing risk of and treatment for certain diseases. Nevertheless, BC may also act to promote disease through the activity of BC derivatives that form in the presence of external toxicants such as cigarette smoke and endogenously-produced reactive oxygen species. The present investigation evaluates the dose-dependent cardioprotective and possibly harmful properties of BC in a rat model. Adult male rats were gavage-fed BC for 4 weeks, at dosages of either 0, 30 or 150 mg/kg/day. Then, hearts excised from the animals were mounted in a "working heart" apparatus and subjected to 30 min of global ischemia, followed by 120 min of reperfusion. A panel of cardiac functional evaluations was conducted on each heart. Infarct size and total antioxidant capacity of the myocardium were assessed. Heart tissue content of heme oxygenase-1 (HO-1) by Western blot analysis; and potential direct cytotoxic effects of BC by MTT assay were evaluated. Hearts taken from rats receiving 30 mg/kg/day BC exhibited significantly improved heart function at lower reperfusion times, but lost this protection at higher BC dosage and longer reperfusion times. Myocardial HO-1 content was significantly elevated dose-responsively to both BC dosage. Finally, in vitro evaluation of BC on H9c2 cells showed that the agent significantly improved vitality of these cells in a dose range of 2.5-10 µM. Although data presented here do not allow for a comprehensive mechanistic explanation for reduced cardioprotection at high dose BC, it is speculated that since Fe2+ produced as a metabolite of HO-1 activity, may determine whether BC acts as an antioxidant or prooxidant agent, the strong induction of this enzyme in response to ischemia/reperfusion-induced oxidative stress may account for the high-dose BC loss of cardioprotection.
Assuntos
Cardiotônicos/farmacologia , Coração/efeitos dos fármacos , beta Caroteno/administração & dosagem , Animais , Antioxidantes/metabolismo , Heme Oxigenase-1/metabolismo , Masculino , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RatosRESUMO
In the present study, we investigated the effects of sour cherry seed extract (SCSE) on a variety of systemic processes that contribute to general health and viability of human subjects. The experiments were conducted according to a double-blind protocol in which six healthy individuals were administered 250-mg/day SCSE for 14 days, while four were treated with placebo. Peripheral blood was collected before and after the treatment period. Samples were analyzed for levels of selected cells, enzymes, or metabolites. Subjects that received SCSE showed increases in the values of mean cell volume, serum transferrin, mean peroxidase index, and representation of peripheral blood lymphocytes. On the other hand, decreases were observed in circulating neutrophils and ferritin levels. Changes observed in the present study do not fit into a clear pattern that might yield additional in-depth understanding of SCSE-mediated alterations in physiologic responses. The most encouraging result of the present study is the absence of any indication of toxicity by subjects consuming the extract.
Assuntos
Extratos Vegetais/farmacologia , Prunus/química , Sementes/química , Adulto , Tamanho Celular , Método Duplo-Cego , Feminino , Ferritinas/sangue , Voluntários Saudáveis , Testes Hematológicos , Heme Oxigenase-1/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Peroxidase/química , Transferrina/químicaRESUMO
Cardiovascular diseases are primary cause of death worldwide, particularly among populations with sedentary lifestyles and diets rich in animal products and processed foods. Currently, public health countermeasures to these disorders focus on costly and often marginally effective interventions administered only after the development of disease. These countermeasures are mainly palliative and fail to address the underlying causes of cardiac pathologies. Previously, the authors of this report have demonstrated that sour cherry seed kernel extract (SCSE), a nontoxic low-cost plant material, strongly preserves tissues through induction of heme oxygenase-1 (HO-1), a critical host antioxidant defense enzyme. This investigation seeks to characterize underlying mechanisms of SCSE-mediated tissue protection. Isolated hearts from Sprague-Dawley rats fed 30 mg·kg·d SCSE for 8 weeks, and untreated controls were mounted in a "working heart" apparatus and subjected to ischemia and reperfusion. A panel of cardiac functional evaluations was conducted on each heart. Infarct size assessments were made along with Western blot and immunohistochemical analysis for selected proteins involved in cardiovascular homeostasis. SCSE treatment was observed to improve postischemic cardiac functions and suppress infarct size. Analysis of the outcomes produced by this study is consistent with SCSE cardioprotection that involve interaction of Bcl-2 and HO-1.
Assuntos
Cardiotônicos/farmacologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Extratos Vegetais/farmacologia , Prunus/química , Animais , Western Blotting , Cardiotônicos/isolamento & purificação , Heme Oxigenase-1/metabolismo , Masculino , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/complicações , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , SementesRESUMO
The external use of curcumin is rare, although it can be a valuable active ingredient in the treatment of certain inflammatory diseases. The aim of our experimental work was to formulate topical dosage forms containing curcumin for the treatment of atopic dermatitis. Curcumin has extremely poor solubility and bioavailability, so we have tried to increase it with the usage of self-emulsifying drug delivery systems. Creams and gels were formulated using penetration-enhancing surfactants and gelling agents. The release of the drug from the vehicle and its penetration through the membrane were determined using a Franz diffusion cell. An MTT cytotoxicity and in vitro antioxidant assays were performed on HaCaT cell line. The in vivo anti-inflammatory effect of the preparations was tested by measuring rat paw edema. In addition, we examined the degree of inflammation induced by UV radiation after pretreatment with the cream and the gel on rats. For the gels containing SNEDDS, the highest penetration was measured after half an hour, while for the cream, it took one hour to reach the maximum concentration. The gel containing Pemulen TR-1 showed the highest drug release. It was determined that the curcumin-containing preparations can be safely applied on the skin and have antioxidant effects. The animal experiments have proven the effectiveness of curcumin-containing topical preparations.