DEFAR - Departamento de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530
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Resultados da Pesquisa
Item Effects of experimental conditions on solubility measurements for BCS classification in order to improve the biowaiver guidelines.(2021) Monteiro, Patrícia Fernanda; Barcellos, Neila Marcia Silva; Caldeira, Tamires Guedes; Reis, Adriana Cotta Cardoso; Ribeiro, Amanda Santos; Souza, Jacqueline deAmong the methods described for determining the solubility, shake-flask is suitable to evaluate the equilibrium solubility according to the BCS. Nevertheless, experimental conditions related to the shake-flask method are not well described. Evaluating the effects of experimental conditions on solubility measurements by shake-flask method is important and contributes in biowaiver decision. For this work, propranolol hydrochloride and nimesulide were used as model compound of high and low solubility, respectively. Equilibrium solubility was evaluated at 37 oC, 100 rpm during 48 hours in buffer media. Effects of the rotation speed, temperature, substance in excess and aliquot withdrawn were evaluated. Small variations of temperature caused significant differences in the solubility and then this parameter must be controlled. Excess of raw material influenced the results of the nimesulide, then, little excess is recommended. Rotation speed did not cause differences in the equilibrium solubilities, but at 150 rpm the equilibrium was reached faster. Aliquot did not present significant differences, but excessive withdrawn should be avoided. Therefore, the evaluation of equilibrium solubility using shake-flask method must be performed in physiological pH conditions, 37 ± 1 oC, substance in excess 10% above saturation, 50, 100 or 150 rpm and aliquot withdrawn not more than 10% of the media volume.Item Novel insights to enhance therapeutics with acyclovir in the management of herpes simplex encephalitis.(2021) Assis, Maria Silvia Gurgel; Pedrosa, Taciane Cristina Fernandes; Moraes, Fernanda Segurasse de; Caldeira, Tamires Guedes; Pereira, Gislaine Ribeiro; Souza, Jacqueline de; Ruela, Andre Luís MoraisAcyclovir is an antiviral drug poorly absorbed in the gastrointestinal tract due to its hydrophilicity, with low oral bioavailability (~20%). Although acyclovir is prescribed in the management of herpes simplex encephalitis (HSE), the disease has a poor prognosis, particularly if the treatment is delayed, reaching mortality rates of 70% if left untreated. Thus, high acyclovir doses are administered by intravenous (IV) infusion, usually at a dosage of 10 mg kg1 8-hourly in adults with normal renal function. However, the mortality related to HSE treated with acyclovir remains high (~20%) and permanent sequelae are commonly reported after 1 year (~50%). This review analyzed clinical trials following IV acyclovir administration. Novel insights aiming to improve drug bioavailability were reviewed, including acyclovir or its prodrugs, leading to the systemic distribution of the drug or drug targeting. Much research effort has been made to improve antiviral therapy, searching for delivery systems increasing acyclovir bioavailability by non-invasive pathways, such as oral and nasal pathways, or parenterally administered nanotechnology-based systems leading to drug targeting. Nanocarriers administered by non-invasive pathways represent feasible alternatives to treat HSE, even though not be industrially manufactured yet.Item Stability and degradation kinetics of an ethanolic extract and tincture of aerial parts from lychnophora passerina (Brazilian arnica).(2021) Ugoline, Bruno César de Albuquerque; Souza, Jacqueline de; Caldeira, Tamires Guedes; Guimarães, Dênia Antunes SaúdePrevious studies have demonstrated the anti-infammatory and antihyperuricemic activities of dried ethanolic extract of the aerial parts of Lychnophora passerina (Mart ex DC.) Gardner, Asteraceae, and then the potential to become a pharmaceutical product. However, many of the constituents present in these medicines can be degraded, raising serious concerns about the stability of products. Considering the impact on the quality of herbal medicines, this study evalu- ated the stability of a dried ethanolic extract and tincture of the aerial parts of L. passerina. For the accelerated stability study, the dried ethanolic extract and tincture were stored at 40±2 °C for 6 months. For the long-term stability study, the dried ethanolic extract was stored at 30±2 °C for 12 months. The organoleptic properties and goyazensolide content were analyzed. The pH, relative density, and dry residue were evaluated for the tincture. In addition, forced degradation and stability studies at room temperature (25±2 °C) were carried out. In glass bottles that were hermetically sealed and protected from light, the dried ethanolic extract remained stable for 3 months when stored at 30±2 °C and for 12 months at 25±2 °C. The tinctures remained stable for 6 months when stored at 25±2 °C. In addition, the dried ethanolic extract and tincture showed zero-order degradation kinetics. The dried ethanolic extract and tincture of L. passerina had greater stability when compared to preparations of other species of Lychnophora. Thus, this species could be directed for phar- maceutical preparations aimed at use by the population.Item Eremantholide C from aerial parts of Lychnophora trichocarpha, as drug candidate : fraction absorbed prediction in humans and BCS permeability class determination.(2021) Caldeira, Tamires Guedes; Guimarães, Dênia Antunes Saúde; González Álvarez, Isabel; Bermejo, Marival; Souza, Jacqueline deBackground Lychnophora trichocarpha (Spreng.) Spreng. ex Sch.Bip has been used in folk medicine to treat pain, inflammation, rheumatism and bruises. Eremantholide C, a sesquiterpene lactone, is one of the substances responsible for the anti-inflammatory and anti-hyperuricemic effects of L. trichocarpha. Objectives Considering the potential to become a drug for the treatment of inflammation and gouty arthritis, this study evaluated the permeability of eremantholide C using in situ intestinal perfusion in rats. From the permeability data, it was possible to predict the fraction absorbed of eremantholide C in humans and elucidate its oral absorption process. Methods In situ intestinal perfusion studies were performed in the complete small intestine of rats using different concentrations of eremantholide C: 960 μg/ml, 96 μg/ml and 9.6 μg/ml (with and without sodium azide), in order to verify the lack of dependence on the measured permeability as a function of the substance concentration in the perfusion solutions. Results Eremantholide C showed Peff values, in rats, greater than 5 × 10−5 cm/s and fraction absorbed predicted for humans greater than 85%. These results indicated the high permeability for eremantholide C. Moreover, its permeation process occurs only by passive route, because there were no statistically significant differences between the Peff values for eremantholide C. Conclusion The high permeability, in addition to the low solubility, indicated that eremantholide C is a biologically active substance BCS class II. The pharmacological activities, low toxicity and biopharmaceutics parameters demonstrate that eremantholide C has the necessary requirements for the development of a drug product, to be administered orally, with action on inflammation, hyperuricemia and gout.Item Gliclazide : biopharmaceutics characteristics to discuss the biowaiver of immediate and extended release tablets.(2020) Mapa, Bruna de Carvalho; Araújo, Lorena Ulhôa; Barcellos, Neila Marcia Silva; Caldeira, Tamires Guedes; Souza, Jacqueline deThe lists of essential medicines of the World Health Organization (WHO) and Brazil include gliclazide as an alternative to the oral antidiabetic drug of first choice, metformin, in the treatment of type 2 diabetes mellitus because of its pharmacokinetic profile and few side effects. Thus, it is also considered by WHO and the International Pharmaceutical Federation (FIP) as a drug candidate to biowaiver, which is the evaluation of how favorable the biopharmaceutics characteristics are in order to obtain waiver from the relative bioavailability/bioequivalence (RB/BE) studies to register new medicines. This paper presents a review about the solubility, permeability and dissolution of gliclazide. A critical analysis of the information allowed to identify gliclazide as a Biopharmaceutics Classification System (BCS) Class II drug. Therefore, new drugs in immediate release dosage forms will not be eligible for biowaiver. Regarding the extended release dosage forms, besides the limited solubility, no information on the comparative dissolution profile was found, which would be necessary to analyze a possible biowaiver for a smaller dosage. It can be concluded that the registration of new medicines containing gliclazide must undergo RB/BE studies, since there is not enough evidence to recommend the replacement and waiver of such studies for immediate and extended release formulations.Item The evaluation of valsartan biopharmaceutics properties.(2020) Castro, Lara Maria Lopes de; Souza, Jacqueline de; Caldeira, Tamires Guedes; Mapa, Bruna de Carvalho; Soares, Anna Flávia Matos; Gomes, Bruna Pegorelli; Croce, Carolina Carvalho Della; Barcellos, Neila Marcia SilvaBackground: Solubility, intestinal permeability and dissolution are the main factors that govern the rate and extent of drugs absorption and are directly related to bioavailability. Biopharmaceutics Classification System (BCS) is an important tool that uses in vitro results for comparison with bioavailability in vivo (biowaiver). Valsartan is widely used in the treatment of hypertension and shows different BCS classification in the literature (BCS class II or III). Objective: This work proposes the study of valsartan biopharmaceutics properties and its BCS classification. Method: High performance liquid chromatography (HPLC) method was developed and validated to quantify the drug in buffers pH 1.2, 4.5 and 6.8. Valsartan solubility was determined in these three different media using shake flask method and intrinsic dissolution rate. Evaluation of dissolution profile from coated tablets was conducted. Results: The low solubility (pH 1.2 and 4.5) and high solubility (pH 6.8) was observed for both solubility methods. Permeability data reported from literature showed that valsartan is a low permeability drug. Valsartan presented rapid release profile only in pH 6.8. Conclusion: We defined that valsartan is a class IV drug, in disagreement with what has been published so far. It is important to emphasize that the conditions considered here are the indicated to define the biopharmaceutics classification by regulatory agencies.Item Polymorphic characterization and implications on biopharmaceutics properties of potential anti-inflammatory drug candidate eremantholide C from Lychnophora trichocarpha (Brazilian Arnica).(2019) Caldeira, Tamires Guedes; Guimarães, Dênia Antunes Saúde; Lacerda, Dâmaris Laignier Rodrigues de; Mussel, Wagner da Nova; Yoshida, Maria Irene; Souza, Jacqueline deObjectives: To perform the polymorphic and physicochemical characterization of the potential anti-inflammatory drug, eremantholide C (EREC), as well as to evaluate the influence of these characteristics on its biopharmaceutics classification. Methods Eremantholide C was obtained from chloroformic extract of Lychnophora trichocarpha and crystallized in two distinct solvents: chloroform (EREC 1) and ethyl acetate (EREC 2). To evaluate the polymorphism, EREC samples were submitted to melting point, purity, infrared spectroscopy, differential scanning calorimetry (DSC), X-ray powder diffraction, optical microscopy and scanning electron microscopy analysis. In addition, EREC samples crystallized after intrinsic dissolution study were submitted to DSC and X-ray powder diffraction analysis. Key findings EREC 1 showed fusion at 234.7–241.6 °C, while EREC 2 showed fusion at 238.6–243.7 °C. No polymorphic transitions were observed during the intrinsic dissolution experiment. A single sharp endothermic peak was obtained for the EREC samples. X-ray diffraction showed no crystallographic differences between the EREC samples. EREC 1 and EREC 2 showed birefringence under polarized light and indefinite morphology; however, the shape of the crystals was common to the two samples. Conclusions: Eremantholide C does not present classical or morphological polymorphism; therefore, there is no influence of crystalline transitions in the solubility and consequently in its biopharmaceutics classification and oral absorption process.Item Determination of intestinal permeability using in situ perfusion model in rats : challenges and advantages to BCS classification applied to digoxin.(2018) Caldeira, Tamires Guedes; Ruiz Picazo, Alejandro; Lozoya Agullo, Isabel; Guimarães, Dênia Antunes Saúde; González Álvarez, Marta; Souza, Jacqueline de; González Álvarez, Isabel; Bermejo, MarivalThe purpose of this work was to describe the closed loop in situ perfusion method in rats and to compare the difficulties and advantages with other methods proposed by regulatory agencies for BCS classification and finally to illustrate its application to evaluate the permeability of digoxin at relevant clinical concentrations. Digoxin was evaluated at two concentration levels: 1.0 μg/ml (with and without sodium azide 65.0 μg/ml) and 6.0 μg/ ml. These concentrations correspond to the ratio of the highest dose strength (0.25 mg) and the highest single dose administered (1.5 mg) and the 250 ml of water. In situ closed loop perfusion studies in rats were performed in the whole small intestine and also in duodenum, jejunum and ileum segments to evaluate the relevance of Pgp secretion in the overall permeability. A kinetic modelling approach involving passive permeation and efflux transport mechanism allowed the estimation of the passive diffusional component and the Michaelis-menten parameters. The estimated Km value demonstrated that at clinical luminal concentrations the efflux process is not saturated and then it could be inhibited by other drugs, excipients or food components leading to the already reported clinical drug-drug and drug-food interations. The present data confirms from a mechanistic point of view these interactions.Item Development and validation of a stability indicating method for quantification of the sesquiterpene lactone eremantholide C from Lychnophora trichocarpha (Brazilian arnica).(2017) Henriques, Bárbara Oliveira; Guimarães, Dênia Antunes Saúde; Caldeira, Tamires Guedes; Souza, Jacqueline dePharmacological activities as anti-inflammatory, anti-hyperuricemic, anti-gouty arthritis, antitumor and trypanocidal activities of the aerial parts from Lychnophora trichocarpha (Spreng.) Spreng. ex Sch.Bip., Asteraceae (Brazilian arnica) have already been proved. Eremantholide C is a sesquiterpene lactone and one of the active chemical constituents responsible for these activities presented by L. trichocarpha. Therefore, the aim of this work was to develop and validate a stability indicating HPLC method for eremantholide C. Eremantholide C stability was evaluated in L. trichocarpha ethanolic extract and in its isolated form. Analytical conditions employed C18 column, acetonitrile/water in gradient elution, flow of 0.8 ml/min at 30 °C. To correct for the loss of analyte during sample preparation the use of coumarin as an internal standard was necessary. The developed method provides good separation and resolution of the peaks, allowing quantification of eremantholide C, isolated or directly in the ethanolic extract, in internal standard presence. Validation results showed that this method is linear in the concentration range 2–180 μg/ml, precise, accurate and specific. Stability studies showed that L. trichocarpha ethanolic extract and eremantholide C remain stable for 6 months when stored at room temperature and impermeable glass bottle, therefore they can be used safely and effectively within this period. While at 40 °C there was stability loss, at 8 °C a stability increase was observed for the extract and the isolated eremantholide C. Forced degradation studies showed that eremantholide C degraded under acidic and alkaline conditions and was stable for three days under neutral and oxidative conditions, and when exposed to high temperature. Thus, with the development of a stability indicative method and the application of it in eremantholide C stability studies, the results can guide the development of new products that adequately preserve the original features of the biologically active substance with quality, safety and efficacy.Item In silico and in vitro prediction of gastrointestinal absorption from potential drug eremantholide C.(2018) Caldeira, Tamires Guedes; Guimarães, Dênia Antunes Saúde; Dezani, André Bersani; Serra, Cristina Helena dos Reis; Souza, Jacqueline deObjectives Analysis of the biopharmaceutical properties of eremantholide C, sesquiterpene lactone with proven pharmacological activity and low toxicity, is required to evaluate its potential to become a drug. Methods Preliminary analysis of the physicochemical characteristics of eremantholide C was performed in silico. Equilibrium solubility was evaluated using the shake‐flask method, at 37.0 °C, 100 rpm during 72 h in biorelevant media. The permeability was analysed using parallel artificial membrane permeability assay, at 37.0 °C, 50 rpm for 5 h. The donor compartment was composed of an eremantholide C solution in intestinal fluid simulated without enzymes, while the acceptor compartment consisted of phosphate buffer. Key findings Physicochemical characteristics predicted in silico indicated that eremantholide C has a low solubility and high permeability. In‐vitro data of eremantholide C showed low solubility, with values for the dose/solubility ratio (ml): 9448.82, 10 389.61 e 15 000.00 for buffers acetate (pH 4.5), intestinal fluid simulated without enzymes (pH 6.8) and phosphate (pH 7.4), respectively. Also, it showed high permeability, with effective permeability of 30.4 × 10−6 cm/s, a higher result compared with propranolol hydrochloride (9.23 × 10−6 cm/s). Conclusions The high permeability combined with its solubility, pharmacological activity and low toxicity demonstrate the importance of eremantholide C as a potential drug candidate.