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1.
Polymers (Basel) ; 16(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39339021

RESUMO

Low-density polyethylene (LDPE) has been widely used in various applications due to its flexibility, lightness, and low production cost. However, its massive use in disposable products has raised environmental concerns, prompting the search for more sustainable alternatives. This study aims to investigate the mechanical properties achievable in a composite material utilizing low-density polyethylene (LDPE), potato starch (PS), and cellulose microfibrils (MFCA) at loadings of 0.05%, 0.15%, and 0.30%. Initially, the cellulose acetate microfibrils (MFCA) were produced via an electrospinning process. Subsequently, a dispersive mixture of the aforementioned materials was created through the extrusion and pelletizing process to form pellets. These pellets were then molded by injection molding to produce test specimens in accordance with ASTM D 638, the standard for tensile strength testing. The evaluation of the properties was conducted through mechanical tensile tests (ASTM D638), hardness tests (ASTM D 2240), melt flow index (ASTM D1238), and scanning electron microscopy (SEM). This study determined the influence of cellulose acetate microfibril loadings below 0.3% as reinforcement within a thermoplastic LDPE matrix. It was demonstrated that these microfibrils, due to their length-to-diameter ratio, contribute to an enhancement in the mechanical properties.

2.
Brain Sci ; 14(9)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39335427

RESUMO

Parkinsonian syndromes are considered clinicopathological conditions that are challenging to diagnose. Molecular imaging with [18F]-FDOPA and [18F]-FDG contributes to a more accurate clinical diagnosis by evaluating presynaptic dopaminergic pathways and glucose metabolism, respectively. The aim of this study was to correlate diagnoses made from dual PET/CT with the initial clinical diagnoses, as well as during follow-ups in patients with Parkinsonian syndromes. A secondary objective was to describe the imaging findings. Methods: A total of 150 patients with a clinical diagnosis of neurodegenerative Parkinsonism were evaluated using dual PET/CT. Clinically, 82% were diagnosed with PD, while the remaining 18% had an atypical Parkinsonism. Results: Using dual PET/CT, the most frequent diagnosis was PD in 67% of the patients, with the rest being diagnosed with an atypical Parkinsonism. In an agreement analysis between the initial clinical diagnosis and the imaging diagnosis by dual PET/CT, a concordance of 94.1% (n = 95) was observed for PD. In the remaining patients, the clinical diagnosis differed from that suggested by dual PET/CT, with atypical Parkinsonian syndromes being diagnosed as DLB in 40% (n = 4), PSP in 46.7% (n = 7), MSA-C in 75% (n = 6), MSA-P in 70% (n = 7), and CBD in 66.7% (n = 4). A total of 38.66% (n = 58) of patients were followed up (median follow-up of 27 months), with a Kappa coefficient of 0.591 (p < 0.001), suggesting substantial agreement. Conclusions: Dual FDOPA-FDG PET/CT demonstrated moderate agreement with the initial clinical diagnosis of Parkinsonism and moderate to substantial agreement during follow-up. This dual technique, therefore, stands out in differentiating between types of Parkinsonisms.

3.
J Pharm Biomed Anal ; 245: 116186, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692216

RESUMO

The inflorescences of the Mexican gordolobo are used as a folk medicine to treat various respiratory diseases. Currently, the botanical species that bear the name Mexican gordolobo belong to the genera Gnaphalium and Pseudognaphalium. Despite a long history of traditional use, most Mexican gordolobo species have never been fully chemically characterized, and the range of constituents in the species has not been comprehensively reported. To establish a quality control and chemical characterization method, a total of 49 samples belonging to 18 species of Pseudognaphalium and four species of Gnaphalium were studied. Nine flavones were quantified using a UPLC-PDA method. The method was validated in terms of linearity (R2 > 0.99), precision (intra- and inter-day: 0.1-3.9%), accuracy (96-103%), detection limit (10 ng/mL), limit of quantification (25 ng/mL) and robustness. 3-Methylquercetin, luteolin, quercetin, 3,5-dihydroxy-6,7,8-trimethoxyflavone, apigenin and gnaphaliin A were present at relatively high levels in most of the samples analyzed. The samples of P. oxyphyllum and P. liebmannii showed the highest content of the 9 compounds analyzed. Whereas the samples of the 5 species of Gnaphalium showed the lowest levels, including non-detectable, of the 9 compounds quantified. This marks an important difference with Pseudognaphalium species. Furthermore, using UHPLC-ESI-QToF data with targeted and non-targeted approaches, 57 compounds, were identified in Mexican gordolobo samples. Flavonoids were the main group of compounds found in Mexican gordolobo.


Assuntos
Flavonas , Gnaphalium , Extratos Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Flavonas/análise , Flavonas/química , Gnaphalium/química , Extratos Vegetais/química , Extratos Vegetais/análise , Limite de Detecção , Reprodutibilidade dos Testes , México , Controle de Qualidade , Medicina Tradicional/métodos , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas/métodos
4.
Polymers (Basel) ; 15(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37959929

RESUMO

In recent decades, there has been an increasing focus on the alarming decline in global bee populations, given their critical ecological contributions to natural pollination and biodiversity. This decline, marked by a substantial reduction in bee colonies in forested areas, has serious implications for sustainable beekeeping practices and poses a broader risk to ecological well-being. Addressing these pressing issues requires innovative solutions, one of which involves the development and fabrication of beehives crafted from composite materials that are ecologically compatible with bee biology. Importantly, these materials should also exhibit a high resistance to environmental factors, such as ultraviolet (UV) radiation, in order to maintain their mechanical integrity and longevity. To investigate this, we conducted accelerated UV degradation tests on a variety of composite materials to rapidly assess their susceptibility to UV-induced changes. High-density polyethylene (HDPE) served as the matrix material and was reinforced with natural fibers, specifically fique fibers (Furcraea bedinghausii), banana fibers, and goose feathers. Our findings indicate that UV radiation exposure results in a noticeable reduction in the tensile strength of these materials. For example, wood composites experienced a 48% decline in tensile strength over a 60-day period, a rate of deterioration notably higher than that of other tested composite materials. Conversely, HDPE composites fortified with banana fibers initially demonstrated tensile strengths exceeding 9 MPa and 10 MPa. Although these values gradually decreased over the observation period, the composites still displayed favorable stress-strain characteristics. This research underscores the substantial influence of UV radiation on the longevity and efficacy of beehive materials, which in turn affects the durability of natural wood hives exposed to these environmental factors. The resultant increased maintenance and replacement costs for beekeepers further emphasize the need for judicious material selection in beehive construction and point to the viability of the composite materials examined in this study.

5.
J Ethnopharmacol ; 293: 115313, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35461988

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Amphipterygium adstringens Schiede ex Schltdl (Anacardiaceae), commonly known as 'cuachalalate' has been used in Mexican traditional medicine for the treatment of skin and oral lesions, gastric ulcers, and other conditions. The use as wound healing of the bark of this plant has been known since before the Spanish conquest of Mexico. Its uses are mentioned in the first writings of the Spanish in the 16th century. It is important to highlight that its use for wound healing treatment has no scientific previous reports. AIM OF THE STUDY: The objectives of this study were to determine the wound healing effect of the hydroalcoholic extract of the stem bark of Amphipterygium adstringens and its main metabolites, using a model of excision in the back of Wistar rats. To evaluate its antimicrobial effect against common bacteria that living on the skin of wounds and to evaluate its effect on angiogenesis. MATERIALS AND METHODS: The hydroalcoholic extract of cuachalalate (HAE, 10 mg/wound/day), the 3α-hydroxymasticadienoic acid (3 MA, 300 µg/wound/day), the masticadienoic acid (MA, 300 µg/wound/day), and a mixture of anacardic acids (ANA, 300 µg per wound) were tested in a murine excision model topically for 15 days, to evaluate their wound-healing effect. The results were reported in a wound closure percentage (n = 30 animals per treatment curve), using pirfenidone (PIR, 8% in vehicle) as a reference drug. In addition, histologic analysis was performed to evaluate the structure and quality of the scar. The effect on angiogenesis was assessed using the chick embryo chorioallantoic membrane (CAM) model (n = 6 eggs per treatment). The concentration evaluated for each treatment was 300 µg, using as proangiogenic reference drug the histamine (HIS, 5.6 µg) and as antiangiogenic drugs pirfenidone (9 µg) and acetylsalicylic acid (ASA, 9 µg). The antimicrobial test was performed against S. mutans, S. aureus, P. aeruginosa y E. coli using a minimum inhibitory concentration (MIC) assay. RESULTS: The 3α-hydroxymasticadienoic (3 MA) acid and the anacardic acids (ANA) improve the wound closure by approximates 30% (similar to pirfenidone) in comparison with the control-treated with the vehicle in the proliferative phase. On the other hand, the hydroalcoholic extract of cuachalalate (HAE) did not show an effect on the wound healing process. The histologic analysis demonstrated that the three main metabolites showed an improvement in the scar structure. According to the CAM results, it is probable that the main action mechanism of the 3α-hydroxymasticadienoic acid and the anacardic acids is related to their proangiogenic effect. In addition, ANA showed a modest antimicrobial effect. CONCLUSIONS: The 3α-hydroxymasticadienoic acid and anacardic acids showed a better tissue structure and reduced the time closure of the wound. In addition, the anacardic acids showed antimicrobial effects and both metabolites promote angiogenesis, suggesting that these effects may be related to their action mechanism. These metabolites of cuachalalate could be a good alternative for wound healing treatment.


Assuntos
Anacardiaceae , Ácidos Anacárdicos , Anacardiaceae/química , Ácidos Anacárdicos/química , Animais , Embrião de Galinha , Cicatriz , Escherichia coli , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Pseudomonas aeruginosa , Ratos , Ratos Wistar , Staphylococcus aureus , Cicatrização
6.
Plants (Basel) ; 10(5)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923101

RESUMO

Despite the availability of many anti-pain drugs, in the form of NSAIDs, steroids, gabapentinoids, opioids, and antidepressants, in this study we address the natural compounds belonging to the group of Mexican medicinal plants or "Mexican folk medicine", used for pain management in Mexico. Our interest in this subject is due to the growing idea that "natural is harmless" and to the large number of side effects exhibited in pharmacotherapy. The objective of this review was to document the scientific evidence about Mexican medicinal plants and their derivatives used for inflammatory and neuropathic pain treatment, as well as the mechanisms of action implicated in their antinociceptive effects, their possible adverse effects, and the main pharmacological aspects of each plant or compound. Our data review suggested that most studies on Mexican medicinal plants have used inflammatory experimental models for testing. The anti-pain properties exerted by medicinal plants lack adverse effects, and their toxicological assays report that they are safe to consume; therefore, more studies should be performed on preclinical neuropathic pain models. Moreover, there is no convincing evidence about the possible mechanisms of action involved in the anti-pain properties exerted by Mexican plants. Therefore, the isolation and pharmacological characterization of these plant derivatives' compounds will be important in the design of future preclinical studies.

7.
Plants (Basel) ; 10(1)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33429861

RESUMO

Infusions and poultices prepared from the aerial parts of Baccharis heterophylla Kunth (Asteraceae) are widely used in Oaxaca (Mexico) for relieving painful and inflammatory complaints. Therefore, the antinociceptive potential of an aqueous extract (31.6-316 mg/kg, p.o.) and essential oil (30-177 µg/paw, i.pl.) of the plant was assessed using the formalin test. Both preparations inhibited the formalin-induced nociception response (100-316 mg/kg and 100-177 µg/paw, respectively) during the test's second phase. Chemical analysis of the aqueous extract revealed that the major active components were chlorogenic acid (1), 3,4-di-O-(E)-caffeoylquinic acid (2), 3,5-di-O-(E)-caffeoylquinic acid (3), 4,5-di-O-(E)-caffeoylquinic acid (4), 3,5-di-O-(E)-caffeoylquinic acid methyl ester (5), apigenin (6), genkwanin (7), acacetin (8). Compounds 1-5 and 8 are new for B. heterophylla. A high-pressure liquid chromatographic method for quantifying chlorogenic acid (1) and di-caffeoylquinic acids 2-4 in the plant was developed and validated. Analyses of the essential oil and the headspace solid-phase microextraction products, via gas-chromatography-mass spectrometry, revealed that the major volatiles were ß-pinene, myrcene, D-limonene, ß-caryophyllene, and α-caryophyllene, which have demonstrated antinociceptive properties.

8.
Int. j. morphol ; 38(6): 1722-1728, Dec. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1134504

RESUMO

RESUMEN: La neoplasia quística mucinosa del páncreas (NQMP) es un tumor infrecuente, que afecta predominantemente a mujeres (90-95 %), afectando especialmente entre la quinta y séptima década de la vida; cuyo descubrimiento suele ser incidental. Por lo general, son lesiones solitarias, sin compromiso del conducto pancreático principal; poco sintomáticas y asociadas a malignidad (10 % a 40 %). El objetivo de este manuscrito fue reportar un caso de neoplasia quística mucinosa gigante del páncreas intervenida quirúrgicamente y revisar la evidencia existente respecto de sus características morfológicas, terapéuticas y pronósticas. Mujer de 29 años, con masa abdominal poco sintomática. El diagnóstico se verificó por medio de ultrasonografía, tomografía axial computarizada y resonancia nuclear magnética. Se intervino quirúrgicamente, realizándose pancreatectomía corporocaudal con preservación esplénica, sin incidentes. La paciente fue dada de alta al quinto día, sin complicaciones, y evolucionó de forma adecuada, sin complicaciones postoperatorias. La NMQP es una lesión compleja, que puede asociarse a malignidad, pero el diagnóstico preoperatorio de malignidad no puede establecerse con seguridad. El pronóstico depende de un diagnóstico precoz y un tratamiento oportuno.


SUMMARY: Mucinous cystic neoplasm of the pancreas (MCNP) are variable types of tumors, which predominantly affect women (90-95 %), and usually appear incidentally in the 5th to 7th decade of life. They are generally solitary lesions, with no involvement of the main pancreatic duct, rarely symptomatic and are associated with malignancy (10 % to 40 %). The aim of this manuscript was to report a case of giant mucinous cystic neoplasm of the pancreas surgically treated and review the existing evidence regarding its morphological, therapeutic and prognosis characteristics. Patient: A 29-year-old woman with a slightly symptomatic abdominal mass. The diagnosis was verified with ultrasound, computed axial tomography and magnetic nuclear resonance. The patient underwent surgery; an uneventful corporocaudal pancreatectomy with splenic preservation was performed. She was discharged on the fifth day, and has evolved adequately, without postoperative complications. MCNP is a complex lesion, which can be associated with malignancy, but the preoperative diagnosis of malignancy cannot be established with certainty. Its prognosis depends on early diagnosis and timely treatment.


Assuntos
Humanos , Feminino , Adulto , Pancreatectomia/métodos , Neoplasias Pancreáticas/cirurgia , Cistadenoma Mucinoso/cirurgia , Neoplasias Pancreáticas/diagnóstico por imagem , Baço/cirurgia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Cistadenoma Mucinoso/diagnóstico por imagem
9.
Naunyn Schmiedebergs Arch Pharmacol ; 393(8): 1501-1513, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32242245

RESUMO

The co-administration of 3α-hydroxymasticadienoic acid (3α-OH MDA) and diligustilide (DLG) generates a synergist gastroprotective effect on indomethacin-induced gastric damage. However, the related protective activities of the compounds alone (or in combination) remain unclear. In the present study, we evaluated the anti-inflammatory and antioxidative activities, as well as the potential modulation of important gasotransmitters of each compound individually and in combination using the indomethacin-induced gastric damage model. Male Wistar rats were treated orally with the 3α-OH MDA, DLG, or their combination (at a fixed ratio of 1:1, 1:3, and 3:1) 30 min before the generation of gastric mucosal lesions with indomethacin (30 mg/kg, p.o.). Three hours later, the gastric injury (mm2) was determined. Results from these experiments indicate, in addition to maintaining basal levels of PGE2, the gastroprotective effect of the pre-treatment with 3α-OH MDA (70%), DLG (81%), and their combination (72%) which was accompanied by significant decreases in leukocyte recruitment, as well as decreases in TNF-α and LTB4 gastric levels (p < 0.05). We also found that the pre-treatment maintains the basal antioxidant enzyme activities (SOD) and gastric NO and H2S production even in the presence of indomethacin (p < 0.05). In conclusion, when 3α-OH MDA-DLG is given at a 1:1 combination ratio, the gastroprotective effect and the inflammatory, antioxidant, and gaso-modulation properties are not different from those of treatments using the maximum doses of each compound, revealing that this combination produces promising results for the treatment of gastric ulcers.


Assuntos
Anti-Inflamatórios/farmacologia , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Úlcera Gástrica/prevenção & controle , Triterpenos/farmacologia , Animais , Dinoprostona/metabolismo , Modelos Animais de Doenças , Quimioterapia Combinada , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Sulfeto de Hidrogênio/metabolismo , Indometacina , Leucotrieno B4/metabolismo , Masculino , Óxido Nítrico/metabolismo , Ratos Wistar , Úlcera Gástrica/metabolismo , Úlcera Gástrica/patologia , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Toxicol Rep ; 7: 217-232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32042599

RESUMO

Endopleura uchi, is used for the treatment of inflammatory disease and related to the female reproductive tract. The aim of this study was to evaluate the acute toxicity of the Endopleura uchi stem bark hydroethanolic extract (EEu) in zebrafish, emphasizing the histopathological and biochemical parameters, as well as evaluating the in silico pharmacokinetic and toxicological parameters of the phytochemical/pharmacological marker, bergenin, as their metabolites. The animals were orally treated with EEu at a single dose of 75 mg/kg, 500 mg/kg, 1000 mg/kg and 3000 mg/kg. the oral LD50 of the EEu higher to the dose of 3000 mg/kg. Behavioral, biochemical and histopathological changes were dose dependent. In silico pharmacokinetic predictions for bergenin and its metabolites showed moderate absorption in high human intestinal absorption (HIA) and Caco-2 models, reduced plasma protein binding, by low brain tissue binding and no P-glycoprotein (P-Gp) inhibition. Their metabolism is defined by the CYP450 enzyme, in addition to bergenin inhibition of CYP2C9, CYP3A4 and CYP2C19. In the bergenin and its metabolites in silico toxicity test it have been shown to cause carcinogenicity and a greater involvement of the bergenin with the CYP enzymes in the I and II hepatic and renal metabolism's phases was observed. It is possible to suggest that the histopathological damages are involved with the interaction of this major compound and its metabolites at the level of the cellular-biochemical mechanisms which involve the absorption, metabolization and excretion of these possible prodrug and drug.

11.
Sci Rep ; 9(1): 16622, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719599

RESUMO

The study of pharmacological interactions between herbal remedies and conventional drugs is important because consuming traditional herbal remedies as supplements or alternative medicine is fairly common and their concomitant administration with prescribed drugs could either have a favorable or unfavorable effect. Therefore, this work aims to determine the pharmacological interactions of a turmeric acetone extract (TAE) and its main metabolite (curcumin) with common anti-ulcer drugs (ranitidine and bismuth subsalicylate), using an ethanol-induced ulcer model in Wistar rats. The analysis of the interactions was carried out via the Combination Index-Isobologram Equation method. The combination index (CI) calculated at 0.5 of the affected fraction (fa) indicated that the TAE or curcumin in combination with ranitidine had a subadditive interaction. The results suggest that this antagonistic mechanism is associated to the mucoadhesion of curcumin and the TAE, determined by rheological measurements. Contrastingly, both the TAE and curcumin combined with bismuth subsalicylate had an additive relationship, which means that there is no pharmacological interaction. This agrees with the normalized isobolograms obtained for each combination. The results of this study suggest that mucoadhesion of curcumin and the TAE could interfere in the effectiveness of ranitidine, and even other drugs.


Assuntos
Antiulcerosos/uso terapêutico , Bismuto/uso terapêutico , Curcumina/farmacologia , Etanol/efeitos adversos , Compostos Organometálicos/uso terapêutico , Extratos Vegetais/farmacologia , Ranitidina/uso terapêutico , Salicilatos/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Antiulcerosos/antagonistas & inibidores , Curcuma , Modelos Animais de Doenças , Interações Medicamentosas , Mucosa Gástrica/efeitos dos fármacos , Interações Ervas-Drogas , Masculino , Compostos Organometálicos/antagonistas & inibidores , Ranitidina/antagonistas & inibidores , Ratos , Ratos Wistar , Salicilatos/antagonistas & inibidores , Úlcera Gástrica/induzido quimicamente
12.
Rev. bras. farmacogn ; 29(4): 441-444, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042283

RESUMO

Abstract The present work investigates the chemical composition of seeds of Cascabela thevetioides (Kunth) Lippold, an ornamental shrub of México. Six thevetia cardiac glycosides or thevetosides (thevetin A, B, and C, acetylthevetin A, B and C) were identified from the methanol extract of seeds of C. thevetioides by High-Performance Liquid Chromatography-Mass Spectrometry and by comparison of mass spectral fragmentation patterns. Enzymatic hydrolysis of a sample of thevetosides from methanol extract of seeds and subsequent High-Performance Liquid Chromatography-Mass Spectrometry analysis yielded the monoglycosides neriifolin, acetylneriifolin and acetylperuvoside, previously reported for this plant. For the fisrt time thevetin A, B and C, and acetylthevetin A, B and C are reported as components of seeds of C. thevetioides.

13.
Prog Chem Org Nat Prod ; 108: 1-142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30924013

RESUMO

Herbal medicines are an integral element of alternative medical care in Mexico, and the best testimony to their efficacy and cultural value is their persistence in contemporary Mexican marketplaces where the highest percentages of medicinal and aromatic plants are sold. This chapter summarizes current trends in research on medicinal plants in Mexico, with emphasis on work carried out at the authors' laboratories. The most relevant phytochemical and pharmacological profiles of a selected group of plants used widely for treating major national health problems are described.From this contribution, it is evident that in the last five decades a significant amount of research on medicinal plants has been performed by Mexican scientists. Such efforts have led to the publication of many research papers in noted peer-reviewed journals and technical books. The isolation and structural characterization of hundreds of bioactive secondary metabolites have been accomplished, and most importantly, these studies have tended to support the ethnomedical uses of many different species. A multidisciplinary approach for investigating these plants has led to an increased emphasis on areas such as phytopharmacology, phytotoxicology, quality control, regulation, and conservation issues for these valuable resources. The medicinal plants analyzed so far have shown a very broad chemical diversity of their constituents, which have a high potential for exhibiting novel mechanistic effects biologically. The chapter shows also that there is need to conduct additional clinical studies on herbal drugs, in particular because the longstanding traditional evidence for their safety is not always sufficient to assure their rational use. There is also need to move to "omics" approaches for investigating the holistic effect and the influence of groups of phytochemicals on the whole organism. Mexican scientists may be expected to have bright prospects in this regard, which will imbue medicinal plant research with a new dynamism in the future.


Assuntos
Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Medicina Tradicional , México , Fitoterapia , Extratos Vegetais/farmacologia
14.
Phytomedicine ; 58: 152891, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30901665

RESUMO

BACKGROUND: Swietenia humilis seeds are consumed in Mexico to treat type 2 diabetes; the antihyperglycemic effect of this species was previously demonstrated and related to the presence of tetranortriterpenoids of the mexicanolide class. PURPOSE AND STUDY DESIGN: The present investigation was conducted to determine the mechanism of action of selected mexicanolides, including 2-hydroxy-destigloyl-6-deoxyswietenine acetate (1), methyl-2-hydroxy-3-ß-tigloyloxy-1-oxomeliac-8(30)-enate (2) and humilinolide H (3), using in vivo experiments with hyperglycemic mice, and cell-based models. METHODS: Nicotinamide-streptozotocin hyperglycemic mice (50-130 mg/kg, i.p.) were used to build antihyperglycemic drug-response curves using an oral glucose tolerance test model. In vitro studies were carried out on INSE1, H4IIE and C2C12 cells to assess insulin secretion, glucose-6-phosphatase inhibition, glucose uptake and mitochondrial bioenergetics, respectively. RESULTS: The combination of the decoction of S. humilis or 2-hydroxy-destigloyl-6-deoxyswietenine acetate (mexicanolide 1) with glibenclamide resulted in a reduction of the antihyperglycemic effect while a significant increase was observed when they were dosed with metformin. These effects were related to KATP SUR blockade, insulin secretion in INSE1 cells, and modulation of 5-HT2 receptors. Furthermore, mexicanolides 1-3 inhibited glucose-phosphatase in H4IIE cells, and enhanced glucose uptake and spare respiratory capacity in C2C12 myotubes. CONCLUSION: S. humilis mexicanolides interact with pharmacological targets at pancreas (KATP channels), liver (glucose-6-phosphatase), and skeletal muscle (mitochondria and possibly glucose transporters) to modulate glucose homeostasis, and could be a promising resource to treat type 2 diabetes.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Limoninas/farmacologia , Meliaceae/química , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Teste de Tolerância a Glucose , Glibureto/farmacologia , Hipoglicemiantes/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metformina/farmacologia , México , Camundongos Endogâmicos ICR , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Plantas Medicinais/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-29100966

RESUMO

INTRODUCTION: The development of electrochemical sensors for the detection of small molecules has already had a significant effect on the study of biology because of their selectivity and ability to measure low concentrations of small molecules that regulate various functions in living organisms. Hydrogen sulfide (H2S) is a gasotransmitter produced at low levels in several tissues including the stomach. Here, we propose a new method for detecting low concentrations of this transmitter in the rat stomach, in-vivo and in real time, with applications in pharmacology and physiology. METHODS: Wistar rats fasted for 12h. Then, the control group was given an intragastrical dose of saline. l-Cysteine (50mg/kg) or dl-propargylglycine (50mg/kg) were administered to the test groups to modify the H2S levels. Ranitidine (50mg/kg), omeprazole (40mg/kg) or carbenoxolone (30mg/kg) were used as reference anti-ulcer drugs. Thirty minutes later, the electrode was inserted in the middle of the stomach cavity of the anesthetized animals. The basal levels of H2S were recorded every 5min for 30min. Next, gastric lesions were induced with pure ethanol, and the recording continued for 30 additional minutes. RESULTS: The exogenous administration of an H2S precursor (l-cysteine) increased the level of this gasotransmitter whereas dl-propargylglycine, a selective inhibitor of the enzyme cystathionine γ lyase, reduced the total concentration of H2S. The administration of carbenoxolone, a gastroprotective, increased the total amount of H2S. However, the administration of the anti-secretors omeprazole and ranitidine did not modify the total concentration of H2S. DISCUSSION: This work provides the basis for a real-time analysis of the changes in-vivo of the gasotransmitter H2S in the normal and injured stomach and the exploration of the effect of drugs on the regulation of H2S.


Assuntos
Gasotransmissores/análise , Mucosa Gástrica/metabolismo , Sulfeto de Hidrogênio/análise , Eletrodos Seletivos de Íons , Úlcera Gástrica/metabolismo , Animais , Antiulcerosos/farmacologia , Modelos Animais de Doenças , Etanol/toxicidade , Gasotransmissores/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Ratos , Ratos Wistar , Estômago/efeitos dos fármacos , Úlcera Gástrica/induzido quimicamente , Fatores de Tempo
17.
J Med Food ; 20(9): 830-837, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28731787

RESUMO

Dyslipidemia is caused by disturbances in lipid metabolism that lead to chronic elevations of serum lipids, especially low-density lipoprotein (LDL)-cholesterol and triglycerides, increasing the risk of metabolic syndrome, obesity, diabetes, atherogenic processes, and cardiovascular diseases. The oil from the fruits of Euterpe oleracea (OFEO) is rich in unsaturated fatty acids with potential for treating alterations in lipid metabolism. In this study, we aimed to investigate the effect of OFEO on hyperlipidemia induced by Cocos nucifera L. saturated fat (GSC) in Wistar rats. Chromatographic profile showed that unsaturated fatty acids account for 66.08% in OFEO, predominately oleic acid (54.30%), and saturated fatty acids (palmitic acid 31.6%) account for 33.92%. GSC-induced dyslipidemia resulted in an increase in total cholesterol, LDL-cholesterol, triglycerides, glucose, and liver and abdominal fat, as well as atherogenic processes in the thoracic aorta. OFEO treatment did not reduce hypertriglyceridemia, but did reduce total cholesterol and LDL-cholesterol, thus contributing to the antiatherogenic action of OFEO. OFEO treatment inhibited the formation of atheromatous plaques in the vascular endothelium of the treated rats, as well as those who were treated with simvastatin. The results obtained suggest that OFEO has an antiatherogenic effect in a rat model of dyslipidemia.


Assuntos
Cocos/efeitos adversos , Dislipidemias/dietoterapia , Euterpe/química , Ácidos Graxos/efeitos adversos , Óleos de Plantas/metabolismo , Animais , Aorta Torácica/metabolismo , Colesterol/sangue , LDL-Colesterol/sangue , Cocos/química , Dislipidemias/etiologia , Dislipidemias/metabolismo , Ácidos Graxos/metabolismo , Frutas/química , Frutas/metabolismo , Humanos , Masculino , Ratos , Ratos Wistar , Triglicerídeos/sangue
18.
Molecules ; 22(2)2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28216594

RESUMO

Demethylisoencecalin (1) and caleins A (4) and C (5) (3.16-31.6 mg/kg, p.o.), the major components from an infusion of Calea ternifolia controlled postprandial glucose levels during an oral sucrose tolerance test (OSTT, 3 g/kg) in normal and nicotinamide/streptozotocin (NA/STZ, 40/100 mg/kg) hyperglicemic mice. The effects were comparable to those of acarbose (5 mg/kg). During the isolation of 1, 4, and 5, four additional metabolites not previously reported for the plant, were obtained, namely 6-acetyl-5-hydroxy-2-methyl-2-hydroxymethyl-2H-chromene (3), herniarin (6), scoparone (7), and 4',7-dimethylapigenin (8). In addition, the structure of calein C (5) was confirmed by X-ray analysis. Pharmacological evaluation of the essential oil of the species (31.6-316.2 mg/kg, p.o.) provoked also an important decrement of blood glucose levels during an OSTT. Gas chromatography coupled with mass spectrometry (GC-MS) analysis of the headspace solid phase microextraction (HS-SPME)-adsorbed compounds and active essential oil obtained by hydrodistillation revealed that chromene 1 was the major component (19.92%); sesquiterpenes represented the highest percentage of the essential oil content (55.67%) and included curcumene (7.10%), spathulenol (12.95%) and caryophyllene oxide (13.0%). A suitable High Performance Liquid Chromatography (HPLC) method for quantifying chromenes 1 and 6-hydroxyacetyl-5-hydroxy-2,2-dimethyl-2H-chromene (2) was developed and validated according to standard protocols.


Assuntos
Asteraceae/química , Benzopiranos/farmacologia , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Óleos Voláteis/química , Animais , Benzopiranos/química , Benzopiranos/isolamento & purificação , Glicemia , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Plantas Medicinais , Sesquiterpenos/isolamento & purificação , Microextração em Fase Sólida , Testes de Toxicidade Aguda
19.
Pharmacology ; 99(5-6): 268-274, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28219076

RESUMO

BACKGROUND: N-benzylpiperazine (BZP) belongs to a class of piperazine derivatives (PZDs) that have emerged as recreational drugs. These compounds increase the release of dopamine and serotonin. BZP mimics the psychoactive effects of 3,4-methylenedioxymethylamphetamine. BZP is metabolized to N-benzylethylenediamine (BEDA) and benzylamine. The compound N,N'-dibenzylpiperazine (DBZP) is obtained as a byproduct during the synthesis of BZP. Some PZDs have shown effects on memory; however, there are no previous reports on the activity of BZP, BEDA, and DBZP on memory or on a description of their neuropharmacological profile. We evaluated the effects of these compounds on acquisition, formation, and consolidation memory and explored their neuropharmacological profile in mice. METHODS: We used the passive avoidance test to evaluate the nootropic effect and for memory experiments. We also evaluated the sedative, myo-relaxant, motor coordination, anxiogenic, and locomotor activity of these compounds. RESULTS: We showed that BZP, its metabolite BEDA, and the disubstituted analogue DBZP enhance the memory and show anxiogenic effects. BZP, as well as DBZP but not BEDA, showed a strong myo-relaxant effect without impairing motor coordination. CONCLUSIONS: BZP and BEDA enhanced the acquisition and consolidation of memory, whereas DBZP only enhances the acquisition of the memory. BEDA and DBZP have an anxiogenic profile similar to that of BZP. BEDA and DBZP represent new psychoactive compounds with the potential to be new BZP-like recreational entities.


Assuntos
Benzilaminas/farmacologia , Etilenodiaminas/farmacologia , Memória/efeitos dos fármacos , Piperazinas/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos
20.
Pharm Biol ; 55(1): 96-100, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27927103

RESUMO

CONTEXT: Agastache mexicana ssp. mexicana (Kunth) Lint & Epling (Lamiaceae), popularly known as 'toronjil morado', is used in Mexican traditional medicine for the treatment of several diseases such as hypertension, anxiety and respiratory disorders. OBJECTIVE: This study investigates the relaxant action mechanism of A. mexicana ssp. mexicana essential oil (AMEO) in guinea-pig isolated trachea model. MATERIALS AND METHOD: AMEO was analyzed by GC/MS. The relaxant effect of AMEO (5-50 µg/mL) was tested in guinea-pig trachea pre-contracted with carbachol (3 × 10 - 6 M) or histamine (3 × 10 - 5 M) in the presence or absence of glibenclamide (10 - 5 M), propranolol (3 × 10 - 6 M) or 2',5'-dideoxyadenosine (10 - 5 M). The antagonist effect of AMEO (10-300 µg/mL) against contractions elicited by carbachol (10 - 15-10 - 3 M), histamine (10 - 15-10 - 3 M) or calcium (10-300 µg/mL) was evaluated. RESULTS: Essential oil composition was estragole, d-limonene and linalyl anthranilate. AMEO relaxed the carbachol (EC50 = 18.25 ± 1.03 µg/mL) and histamine (EC50 = 13.3 ± 1.02 µg/mL)-induced contractions. The relaxant effect of AMEO was not modified by the presence of propranolol, glibenclamide or 2',5'-dideoxyadenosine, suggesting that effect of AMEO is not related to ß2-adrenergic receptors, ATP-sensitive potassium channels or adenylate cyclase activation. AMEO was more potent to antagonize histamine (pA2' = -1.507 ± 0.122) than carbachol (pA2' = -2.180 ± 0.357). Also, AMEO antagonized the calcium chloride-induced contractions. CONCLUSION: The results suggest that relaxant effect of AMEO might be due to blockade of calcium influx in guinea-pig trachea smooth muscle. It is possible that estragole and d-limonene could contribute majority in the relaxant effect of AMEO.


Assuntos
Agastache/química , Broncoconstrição/efeitos dos fármacos , Broncodilatadores/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Traqueia/efeitos dos fármacos , Animais , Broncodilatadores/isolamento & purificação , Sinalização do Cálcio/efeitos dos fármacos , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Cobaias , Técnicas In Vitro , Masculino , Músculo Liso/metabolismo , Óleos Voláteis/isolamento & purificação , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Traqueia/metabolismo
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