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1.
Heliyon ; 6(11): e05360, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33163675

RESUMO

Natural plants derivatives have gained enormous merits in cancer therapy applications upon formulation with nanomaterials. Curcumin, as a popular research focus has acquired such improvements surpassing its disadvantageous low bioavailability. To this point, the available research data had confirmed the importance of nanomaterial type in orienting cellular response and provoking different toxicological and death mechanisms that may range from physical membrane damage to intracellular changes. This in turn underlines the poorly studied field of nanoformulation interaction with cells as the key determinant in toxicology outcomes. In this work, curcumin-AuNPs-reduced graphene oxide nanocomposite (CAG) was implemented as a model, to study the impact on cellular membrane integrity and the possible redox changes using colon cancer in vitro cell lines (HT-29 and SW-948), representing drug-responsive and resistant subtypes. Morphological and biochemical methods of transmission electron microscopy (TEM), apoptosis assay, reactive oxygen species (ROS) and antioxidants glutathione and superoxide dismutase (GSH and SOD) levels were examined with consideration to suitable protocols and vital optimizations. TEM micrographs proved endocytic uptake with succeeding cytoplasm deposition, which unlike other nanomaterials studied previously, conserved membrane integrity allowing intracellular cytotoxic mechanism. Apoptosis was confirmed with gold-standard morphological features observed in micrographs, while redox parameters revealed a time-dependent increase in ROS accompanied with regressive GSH and SOD levels. Collectively, this work demonstrates the success of graphene as a platform for curcumin intracellular delivery and cytotoxicity, and further highlights the importance of suitable in vitro methods to be used for nanomaterial validation.

2.
PLoS One ; 14(5): e0216725, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31086406

RESUMO

Nanotechnology-based antioxidants and therapeutic agents are believed to be the next generation tools to face the ever-increasing cancer mortality rates. Graphene stands as a preferred nano-therapeutic template, due to the advanced properties and cellular interaction mechanisms. Nevertheless, majority of graphene-based composites suffer from hindered development as efficient cancer therapeutics. Recent nano-toxicology reviews and recommendations emphasize on the preliminary synthetic stages as a crucial element in driving successful applications results. In this study, we present an integrated, green, one-pot hybridization of target-suited raw materials into curcumin-capped gold nanoparticle-conjugated reduced graphene oxide (CAG) nanocomposite, as a prominent anti-oxidant and anti-cancer agent. Distinct from previous studies, the beneficial attributes of curcumin are employed to their fullest extent, such that they perform dual roles of being a natural reducing agent and possessing antioxidant anti-cancer functional moiety. The proposed novel green synthesis approach secured an enhanced structure with dispersed homogenous AuNPs (15.62 ± 4.04 nm) anchored on reduced graphene oxide (rGO) sheets, as evidenced by transmission electron microscopy, surpassing other traditional chemical reductants. On the other hand, safe, non-toxic CAG elevates biological activity and supports biocompatibility. Free radical DPPH inhibition assay revealed CAG antioxidant potential with IC50 (324.1 ± 1.8%) value reduced by half compared to that of traditional citrate-rGO-AuNP nanocomposite (612.1 ± 10.1%), which confirms the amplified multi-potent antioxidant activity. Human colon cancer cell lines (HT-29 and SW-948) showed concentration- and time-dependent cytotoxicity for CAG, as determined by optical microscopy images and WST-8 assay, with relatively low IC50 values (~100 µg/ml), while preserving biocompatibility towards normal human colon (CCD-841) and liver cells (WRL-68), with high selectivity indices (≥ 2.0) at all tested time points. Collectively, our results demonstrate effective green synthesis of CAG nanocomposite, free of additional stabilizing agents, and its bioactivity as an antioxidant and selective anti-colon cancer agent.


Assuntos
Curcumina/química , Curcumina/farmacologia , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Moleculares , Conformação Molecular , Oxirredução
5.
Eur J Med Chem ; 139: 349-366, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-28806615

RESUMO

Early detection and efficient treatment of cancer disease remains a drastic challenge in 21st century. Throughout the bulk of funds, studies, and current therapeutics, cancer seems to aggressively advance with drug resistance strains and recurrence rates. Nevertheless, nanotechnologies have indeed given hope to be the next generation for oncology applications. According to US National cancer institute, it is anticipated to revolutionize the perspectives of cancer diagnosis and therapy. With such success, nano-hybrid strategy creates a marvelous preference. Herein, graphene-gold based composites are being increasingly studied in the field of oncology, for their outstanding performance as robust vehicle of therapeutic agents, built-in optical diagnostic features, and functionality as theranostic system. Additional modes of treatments are also applicable including photothermal, photodynamic, as well as combined therapy. This review aims to demonstrate the various cancer-related applications of graphene-gold based hybrids in terms of detection and therapy, highlighting the major attributes that led to designate such system as a promising ally in the war against cancer.


Assuntos
Ouro/uso terapêutico , Grafite/uso terapêutico , Nanocompostos/uso terapêutico , Neoplasias/tratamento farmacológico , Relação Dose-Resposta a Droga , Ouro/química , Grafite/química , Humanos , Estrutura Molecular , Nanocompostos/química , Neoplasias/diagnóstico , Relação Estrutura-Atividade
6.
Int J Mol Sci ; 17(9)2016 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-27618893

RESUMO

Benzyl α-l-rhamnopyranoside 4, obtained by both conventional and microwave assisted glycosidation techniques, was subjected to 2,3-O-isopropylidene protection to yield compound 5 which on benzoylation and subsequent deprotection of isopropylidene group gave the desired 4-O-benzoylrhamnopyranoside 7 in reasonable yield. Di-O-acetyl derivative of benzoate 7 was prepared to get newer rhamnopyranoside. The structure activity relationship (SAR) of the designed compounds was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antimicrobial activities verified the predictions obtained by the PASS software. Protected rhamnopyranosides 5 and 6 exhibited slight distortion from regular ¹C4 conformation, probably due to the fusion of pyranose and isopropylidene ring. Synthesized rhamnopyranosides 4-8 were employed as test chemicals for in vitro antimicrobial evaluation against eight human pathogenic bacteria and two fungi. Antimicrobial and SAR study showed that the rhamnopyranosides were prone against fungal organisms as compared to that of the bacterial pathogens. Interestingly, PASS prediction of the rhamnopyranoside derivatives 4-8 were 0.49 < Pa < 0.60 (where Pa is probability 'to be active') as antibacterial and 0.65 < Pa < 0.73 as antifungal activities, which showed significant agreement with experimental data, suggesting rhamnopyranoside derivatives 4-8 were more active against pathogenic fungi as compared to human pathogenic bacteria thus, there is a more than 50% chance that the rhamnopyranoside derivative structures 4-8 have not been reported with antimicrobial activity, making it a possible valuable lead compound.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Oligossacarídeos/química , Ramnose/química , Bactérias/efeitos dos fármacos , Sequência de Carboidratos , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Software , Relação Estrutura-Atividade
7.
Molecules ; 21(7)2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27367658

RESUMO

A new series of multipotent antioxidants (MPAOs), namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT) were designed and subsequently synthesized. The structure-activity relationship (SAR) of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS). The antioxidant activities of the synthesized compounds 4-10 were tested by the DPPH bioassay. The synthesized compounds 4-10 inhibited stable DPPH free radicals at a level that is 10(-4) M more than the well-known standard antioxidant BHT. Compounds 8-10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7). With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Hidroxitolueno Butilado/química , Desenho de Fármacos , Bases de Schiff/química , Triazóis/química , Triazóis/farmacologia , Antioxidantes/síntese química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/antagonistas & inibidores , Radicais Livres/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espécies Reativas de Oxigênio/química , Triazóis/síntese química
8.
PLoS One ; 11(6): e0156022, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27272221

RESUMO

A series of new 2-(ethylthio)benzohydrazone derivatives (1-6) were prepared and characterised by IR, 1H NMR, and 13C NMR spectroscopy and mass spectrometry. The newly prepared compounds were screened for their in vitro antioxidant activities using free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Among them, most powerful antioxidant, compound 1 has been selected in order to illustrate anti-ulcer effect on ethanol-induced gastric mucosal lesions in rats. Four groups of Sprague Dawley rats were respectively treated with 10% Tween 20 as ulcer control group, 20 mg/kg omeprazole as reference group, 50 mg/kg and 100 mg/kg compound 1 as experimental animals. Macroscopically, ulcer control group showed extensive hemorrhagic lesions of gastric mucosa compared with omeprazole or compound 1. Rats pre-treated with compound 1 showed increased in gastric pH and gastric mucus. Histologically, ulcer control group showed severe damage to gastric mucosa with edema and leucocytes infiltration of submucosal layer. In immunohistochemical analysis, rats which were pre-treated with compound 1 showed up-regulation of HSP70 and down-regulation of Bax proteins. In conclusion, the gastroprotective effect of compound 1 may be due to its antioxidant activity, and/or due to up-regulation of HSP70 and down-regulation of Bax protein in stained tissue section.


Assuntos
Antioxidantes/farmacologia , Mucosa Gástrica/metabolismo , Gastrite/tratamento farmacológico , Hidrazonas/farmacologia , Animais , Antioxidantes/síntese química , Antioxidantes/química , Regulação para Baixo/efeitos dos fármacos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Edema/metabolismo , Edema/patologia , Feminino , Mucosa Gástrica/patologia , Gastrite/induzido quimicamente , Gastrite/metabolismo , Gastrite/patologia , Glicoproteínas/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Hidrazonas/síntese química , Hidrazonas/química , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Leucócitos/metabolismo , Leucócitos/patologia , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos , Proteína X Associada a bcl-2/biossíntese
9.
Eur J Med Chem ; 101: 295-312, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26150290

RESUMO

Hindered phenols find a wide variety of applications across many different industry sectors. Butylated hydroxytoluene (BHT) is a most commonly used antioxidant recognized as safe for use in foods containing fats, pharmaceuticals, petroleum products, rubber and oil industries. In the past two decades, there has been growing interest in finding novel antioxidants to meet the requirements of these industries. To accelerate the antioxidant discovery process, researchers have designed and synthesized a series of BHT derivatives targeting to improve its antioxidant properties to be having a wide range of antioxidant activities markedly enhanced radical scavenging ability and other physical properties. Accordingly, some structure-activity relationships and rational design strategies for antioxidants based on BHT structure have been suggested and applied in practice. We have identified 14 very sensitive parameters, which may play a major role on the antioxidant performance of BHT. In this review, we attempt to summarize the current knowledge on this topic, which is of significance in selecting and designing novel antioxidants using a well-known antioxidant BHT as a building-block molecule. Our strategy involved investigation on understanding the chemistry behind the antioxidant activities of BHT, whether through hydrogen or electron transfer mechanism to enable promising anti-oxidant candidates to be synthesized.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/farmacologia , Animais , Antioxidantes/síntese química , Hidroxitolueno Butilado/síntese química , Desenho de Fármacos , Humanos , Estrutura Molecular
10.
Eur J Med Chem ; 87: 564-77, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25299680

RESUMO

New multipotent antioxidants (MPAOs), namely 1,3,4-thiadiazoles and 1,2,4-triazoles bearing the well-known free radical scavenger butylated hydroxytoluene (BHT), were designed and synthesized using an acid-(base-) catalyzed intramolecular dehydrative cyclization reaction of the corresponding 1-acylthiosemicarbazides. The structure-activity relationship (SAR) of the designed antioxidants was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antioxidant activity using DPPH and lipid peroxidation assays verified the predictions obtained by the PASS-assisted design strategy. Compounds 4a-b, 5a-b and 6a-b showed an inhibition of stable DPPH free radicals at a 10(-4) M more than the well-known standard antioxidant BHT. Compounds with p-methoxy substituents (4b, 5b and 6b) were more active than o-methoxy substituents (4a, 5a and 6a). With an IC50 of 2.85 ± 1.09 µM, compound 6b exhibited the most promising in vitro inhibition of lipid peroxidation, inhibiting Fe(2+)-induced lipid peroxidation of essential oils derived from the egg yolk-based lipid-rich medium by 86.4%. The parameters for the drug-likeness of these BHT derivatives were also evaluated according to Lipinski's 'rule-of-five'. All of the BHT derivatives were found to violate one of Lipinski's parameters (Log P ≥ 5) even though they have been found to be soluble in protic solvents. The predictive TPSA and %ABS data allow for the conclusion that these compounds could have a good capacity for penetrating cell membranes. Therefore, these novel MPAOs containing lipophilic and hydrophilic groups can be proposed as potential antioxidants for tackling oxidative stress and lipid peroxidation processes.


Assuntos
Antioxidantes/farmacologia , Hidroxitolueno Butilado/análogos & derivados , Desenho de Fármacos , Antioxidantes/síntese química , Antioxidantes/química , Hidroxitolueno Butilado/síntese química , Hidroxitolueno Butilado/farmacologia , Modelos Moleculares , Relação Estrutura-Atividade
11.
ScientificWorldJournal ; 2014: 301879, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24701154

RESUMO

The antifibrotic effects of traditional medicinal herb Caesalpinia sappan (CS) extract on liver fibrosis induced by thioacetamide (TAA) and the expression of transforming growth factor ß1 (TGF-ß1), α-smooth muscle actin (αSMA), and proliferating cell nuclear antigen (PCNA) in rats were studied. A computer-aided prediction of antioxidant and hepatoprotective activities was primarily performed with the Prediction Activity Spectra of the Substance (PASS) Program. Liver fibrosis was induced in male Sprague Dawley rats by TAA administration (0.03% w/v) in drinking water for a period of 12 weeks. Rats were divided into seven groups: control, TAA, Silymarin (SY), and CS 300 mg/kg body weight and 100 mg/kg groups. The effect of CS on liver fibrogenesis was determined by Masson's trichrome staining, immunohistochemical analysis, and western blotting. In vivo determination of hepatic antioxidant activities, cytochrome P450 2E1 (CYP2E1), and matrix metalloproteinases (MPPS) was employed. CS treatment had significantly increased hepatic antioxidant enzymes activity in the TAA-treated rats. Liver fibrosis was greatly alleviated in rats when treated with CS extract. CS treatment was noted to normalize the expression of TGF-ß1, αSMA, PCNA, MMPs, and TIMP1 proteins. PASS-predicted plant activity could efficiently guide in selecting a promising pharmaceutical lead with high accuracy and required antioxidant and hepatoprotective properties.


Assuntos
Caesalpinia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/prevenção & controle , Extratos Vegetais/uso terapêutico , Tioacetamida/toxicidade , Animais , Previsões , Cirrose Hepática/metabolismo , Masculino , Fitoterapia/métodos , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
12.
BMC Complement Altern Med ; 13: 343, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24305067

RESUMO

BACKGROUND: Hepatocellular carcinoma is a common type of tumour worldwide with a high mortality rate and with low response to current cytotoxic and chemotherapeutic drugs. The prediction of activity spectra for the substances (PASS) software, which predicted that more than 300 pharmacological effects, biological and biochemical mechanisms based on the structural formula of the substance was efficiently used in this study to reveal new multitalented actions for Vitex negundo (VN) constituents. METHODS: Experimental studies based on antioxidant and antiproliferative assays verified the predictions obtained by the PASS-predicted design strategy. Antioxidant activity of VN extract was studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Ferric reducing or antioxidant power (FRAP) assays. The antiproliferative activity of VN extract against WRL68 and HepG2 was investigated based on methylthiazol tetrazolium (MTT) spectrophotometric assay. RESULTS: VN extract showed 79.43% inhibition of DPPH stable radical with IC50 13.31 ± 0.18 µg/ml. This inhibition was too closed to butylated hydroxyl toluene (BHT) 82.53% (IC5013.8 ± 0.14) and gallic acid 89.51% (IC50 3.1 ± 0.08). VN extract exhibited the strongest free radical scavenging power compared with two commercial antioxidants, BHT and ascorbic acid. VN increased the activities of antioxidant enzymes in normal embryonic liver cells (WRL68) including, superoxide dismutase (SOD) and glutathione peroxidase (GPX) compared with to H2O2 group. The ethanolic extract of VN showed cytotoxicity to HepG2 cells in a dose and time-dependent manner with IC50 66.46 µg/ml, 57.36 µg/ml and 65.12 µg/ml at 24, 48, and 72-hours incubation respectively, with no sensitivity in WRL68 cells. This was associated with significant elevation in lactate dehydrogenase (LDH) release in HepG2 cells. In addition, the activation of caspase-3 enzyme suggesting that the observed cytotoxicity was mediated via an intrinsic apoptosis pathway. CONCLUSIONS: PASS-predicted plant activity could efficiently help in selecting a promising pharmaceutical leads with high accuracy and required antioxidant and antiproliferative properties. This is the first report on PASS-predicted VN activity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Vitex/química , Análise de Variância , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Caspase 3/metabolismo , Forma Celular , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Células Hep G2 , Humanos , Peróxido de Hidrogênio/metabolismo , Concentração Inibidora 50 , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Malondialdeído/metabolismo , Software
13.
Artigo em Inglês | MEDLINE | ID: mdl-23762157

RESUMO

The hepatoprotective activity of ethanolic extract from the leaves of Vitex negundo (VN) was conducted against thioacetamide- (TAA-) induced hepatic injury in Sprague Dawley rats. The therapeutic effect of the extract was investigated on adult male rats. Rats were divided into seven groups: control, TAA, Silymarin (SY), and VN high dose and low dose groups. Rats were administered with VN extract at two different doses, 100 mg/kg and 300 mg/kg body weight. After 12 weeks, the rats administered with VN showed a significantly lower liver to body weight ratio. Their abnormal levels of biochemical parameters and liver malondialdehyde were restored closer to the normal levels and were comparable to the levels in animals treated with the standard drug, SY. Gross necropsy and histopathological examination further confirmed the results. Progression of liver fibrosis induced by TAA in rats was intervened by VN extract administration, and these effects were similar to those administered with SY. This is the first report on hepatoprotective effect of VN against TAA-induced liver fibrosis.

14.
BMC Complement Altern Med ; 13: 294, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24499255

RESUMO

BACKGROUND: Oxidative stress due to abnormal induction of reactive oxygen species (ROS) molecules is believed to be involved in the etiology of many diseases. Evidences suggest that ROS is involved in nephrotoxicity through frequent exposure to industrial toxic agents such as thioacetamide (TAA). The current investigation was designed to explore the possible protective effects of the leaves of Vitex negundo(VN) extract against TAA-induced nephrotoxicity in rats. METHODS: Twenty four Sprague Dawleyrats were divided into four groups: (A) Normal control, (B) TAA (0.03% w/v in drinking water), (C) VN100 (VN 100 mg/kg + TAA) and (D) VN300 (VN 300 mg/kg + TAA). Blood urea and serum creatinine levels were measured,supraoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels of renal tissue were assayed. Histopathological analysis together with the oxidative stress nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22phox in kidney sections were examined in all experimental groups. RESULTS: Blood urea and serum creatinine levels were increased in TAA group as a result of the nephrotoxicity compared to the VN100 and VN300 groups where, the levels were significantly decreased (p < 0.05). Renal MDA level was significantly decreased (p < 0.05) in the VN-treated groups with increased CAT and SOD activities compared to the TAA group. Light microscopic examination of renal tissues stained by H&E stain and Masson's Trichrome for TAA-treated groups revealed severe histopathological changes, whereas specimens obtained from VN-treated groups showed only mild changes. These findings were supported by immunohistochemical results. CONCLUSIONS: VN extract acts as a natural potent antioxidant to prevent ongoing TAA-induced nephrotoxicity in rats, both biochemically and morphologically.


Assuntos
Nefropatias/tratamento farmacológico , Rim/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Vitex/química , Administração Oral , Animais , Antioxidantes/administração & dosagem , Catalase/metabolismo , Humanos , Rim/enzimologia , Rim/metabolismo , Nefropatias/induzido quimicamente , Nefropatias/enzimologia , Nefropatias/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tioacetamida/toxicidade
15.
BMJ Case Rep ; 20122012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23087269

RESUMO

Absence of the distal crease of the fingers is usually associated with a flexion deformity. A single crease of one or more fingers is found in many syndromes. We present this report as a rare case of absence of interphalangeal crease of the right ring finger with restriction of flexion but without any other anomaly.


Assuntos
Anquilose , Articulações dos Dedos/anormalidades , Dedos/anormalidades , Amplitude de Movimento Articular , Adulto , Anquilose/congênito , Feminino , Humanos , Estudantes de Medicina , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-23365597

RESUMO

Polygonum chinense is a Malaysian ethnic plant with various healing effects. This study was to determine preventive effect of aqueous leaf extract of P. chinense against ethanol-induced gastric mucosal injury in rats. Sprague Dawley rats were divided into seven groups. The normal and ulcer control groups were orally administered with distilled water. The reference group was orally administered with 20 mg/kg omeprazole. The experimental groups received the extracts 62.5, 125, 250, and 500 mg/kg, accordingly. After sixty minutes, distilled water and absolute ethanol were given (5 mL/kg) to the normal control and the others, respectively. In addition to histology, immunohistochemical and periodic acid schiff (PAS) stains, levels of lipid peroxidation, malondialdehyde (MDA), antioxidant enzymes, and superoxide dismutase (SOD) were measured. The ulcer group exhibited severe mucosal damages. The experimental groups significantly reduced gastric lesions and MDA levels and increased SOD level. Immunohistochemistry of the experimental groups showed upregulation and downregulation of Hsp70 and Bax proteins, respectively. PAS staining in these groups exhibited intense staining as compared to the ulcer group. Acute toxicity study revealed the nontoxic nature of the extract. Our data provide first evidence that P. chinense extract could significantly prevent gastric ulcer.

17.
Indian J Pharmacol ; 43(1): 64-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21455425

RESUMO

OBJECTIVES: This study was conducted to determine the effect of ethanolic extract of the dried stems of Tinospora crispa in a male rat model of hepatic fibrosis caused by the hepatotoxin, thioacetamide. MATERIALS AND METHODS: The extract was gavaged daily to the rats, at doses of 100 and 200 mg/kg along with thioacetamide at a dose of 200 mg/kg twice weekly. To assess the effectivity of extract, against thioacetamide, the activity of aminotransferases (alanine aminotransferase, aspartate aminotransferase), alkaline phosphatase (AP); and bilirubin were measured, together with morphological and histopathological indices in the liver of healthy and thioacetamide-treated rats. RESULTS: A significant increase in the activity of liver enzymes, bilirubin and G-glutamyl transferase and gross and histopathological changes were determined. Although previous in vitro study established that this extract had strong antioxidant activity, this in vivo study establishes that this extract contains hepatotoxins whose identity may be quite different from those compounds with antioxidant properties. CONCLUSION: The study confirms that complete reliance on data obtained using in vitro methodologies may lead to erroneous conclusions pertaining to the safety of phytopharmaceuticals.

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