RESUMO
Background and Objectives: Matrix metalloproteinases (MMP) have been implicated as major determinants of tumour growth and metastasis, which are considered two of the main hallmarks of cancer. The interaction of MMP8 and other signalling molecules within and adjacent tumoral tissues, including immune cells, are rather elusive, particularly of adenocarcinoma cell type. In this study, we aimed to investigate the role of MMP8 in non-small cell lung cancer proliferation and invasiveness potential. Materials and Methods: We individually lipofected with two different single guide RNA (sgRNAs) that specifically targeted on MMP8, with CRISPR-Cas 9 protein into the cells. Results: Our results clearly indicated that the lipofection of these complexes could lead to reduced ability of A549 cells to survive and proliferate to form colonies. In addition, when compared to non-transfected cells, the experimental cell groups receiving sgRNAs demonstrated relatively decreased migration rate, hence, wider wound gaps in scratch assay. The quantitative real time-polymerase chain reaction (qRT-PCR) demonstrated significant reduction in the MAP-K, survivin and PI3-K gene expression. MMP8 might have protective roles over tumour growth and spread in our body. Conclusions: The delivery of sgRNAs targeting on the MMP8 gene could induce tumour cell death and arrest cell migratory activity.
Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Neoplasias Pulmonares/genética , Metaloproteinase 8 da Matriz , Invasividade Neoplásica , RNA Guia de CinetoplastídeosRESUMO
Retinal disorders account for a large proportion of ocular disorders that can lead to visual impairment or blindness, and yet our limited knowledge in the pathogenesis and choice of appropriate animal models for new treatment modalities may contribute to ineffective therapies. Although genetic in vivo models are favored, the variable expressivity and penetrance of these heterogeneous disorders can cause difficulties in assessing potential treatments against retinal degeneration. Hence, an attractive alternative is to develop a chemically-induced model that is both cost-friendly and standardizable. Sodium iodate is an oxidative chemical that is used to simulate late stage retinitis pigmentosa and age-related macular degeneration. In this study, retinal degeneration was induced through systemic administration of sodium iodate (NaIO3) at varying doses up to 80â¯mg/kg in Sprague-Dawley rats. An analysis on the visual response of the rats by electroretinography (ERG) showed a decrease in photoreceptor function with NaIO3 administration at a dose of 40â¯mg/kg or greater. The results correlated with the TUNEL assay, which revealed signs of DNA damage throughout the retina. Histomorphological analysis also revealed extensive structural lesions throughout the outer retina and parts of the inner retina. Our results provided a detailed view of NaIO3-induced retinal degeneration, and showed that the administration of 40â¯mg/kg NaIO3 was sufficient to generate disturbances in retinal function. The pathological findings in this model reveal a degenerating retina, and can be further utilized to develop effective therapies for RPE, photoreceptor, and bipolar cell regeneration.
Assuntos
Iodatos/toxicidade , Retina/efeitos dos fármacos , Degeneração Retiniana/patologia , Animais , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Eletrorretinografia , Ratos , Ratos Sprague-Dawley , Retina/patologia , Retina/fisiologiaRESUMO
Dysfunctional or death of retinal photoreceptors is an irreversible phenomenon that is closely associated with a broad range of retinal degenerative diseases, such as retinitis pigmentosa and age-related macular degeneration (AMD), resulting in successive loss of visual function and blindness. In search for viable treatment for retinal degenerative diseases, mesenchymal stem cells (MSCs) has demonstrated promising therapeutic capabilities to repair and replace damaged photoreceptor cells in both in vitro and in vivo conditions. Nevertheless, the dearth of MSC differentiation capacity into photoreceptors has limited its use in cell replacement therapy. Erythropoietin (EPO) has vital role in early neural retinal cell differentiation and demonstrated rescue potential on dying photoreceptor cells. Hence, we aimed to evaluate the differentiation capacity of MSCs into photoreceptor cells in the presence of human EPO protein. We derived the MSC from human Wharton's jelly of umbilical cord and transduced the cells with lentivirus particles encoding EPO and green fluorescent protein (GFP) as reporter gene. The transduced cells were selectively cultured and induced to differentiate into photoreceptors by exposing to photoreceptor differentiation cocktail. Our preliminary results showed that transduced cells exposed to induction medium had an enhanced differentiation capacity when compared to non-transduced cells. Our results demonstrated a novel strategy to increase the yield of in vitro photoreceptor differentiation and may be potentially useful in improving the efficiency of stem cell transplantation for ocular disorders.
Assuntos
Eritropoetina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Diferenciação Celular , Células Cultivadas , Eritropoetina/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células Fotorreceptoras de Vertebrados/citologia , Rodopsina/metabolismo , Transativadores/metabolismo , Geleia de Wharton/citologiaRESUMO
Retinal degeneration is a prominent feature in ocular disorders. In exploring possible treatments, Mesenchymal Stem Cells (MSCs) have been recognized to yield therapeutic role for retinal degenerative diseases. Studies have also displayed that erythropoietin (EPO) administration into degenerative retina models confers significant neuroprotective actions in limiting pathological cell death. In this study, we aimed to use MSCs to deliver EPO and to evaluate the ability of EPO to rescue retinal neurons from dying upon reactive oxidative stress induction. We derived human MSCs from Wharton's jelly (hWJMSCs) of the umbilical cord and cells were transduced with lentivirus particles encoding EPO and a reporter gene of green fluorescent protein (GFP). The supernatants of both transduced and non-transduced cells were collected and used as a pre-conditioning medium for Y79 retinoblastoma cells (retinal neuron cell line) following exposure to glutamate induction. Retinal cells exposed to glutamate showed reduced mitochondrial depolarization and enhanced improvement in cell viability when incubated with pre-conditioned media of transduced cells. Our results established a proof-of-concept that MSCs could be used as a candidate for the delivery of EPO therapeutic gene in the treatment of retinal degenerations.
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Flowers of Tabernaemontana divaricata (L.) R. Br., (Apocynaceae) are used in traditional medicine for analgesic property. The present study was performed to isolate the active principles and investigate the mechanisms involved in the anti-nociception caused by T. divaricata flower methanolic extract (TDFME). The extract in the doses of 125, 250 and 500 mg/kg, p.o was subjected to various assays in acetic acid induced abdominal writhing and formalin induced paw licking test models. Naloxone, L-Arginine, Glibenclamide and Glutamate were used as inducers while Morphine, L-NAME, Methylene blue and Aspirin served as standard drugs. The phytochemical analysis led to the isolation of three indole alkaloids namely Voacangine, Catharanthine and O-acetyl Vallesamine. The anti-nociception produced by TDFME was attenuated significantly (p< 0.001) by the intra-peritoneal pretreatment of naloxone, L-Arginine and glibenclamide. The nociception produced by glutamate was inhibited by TDFME. TDFME also enhanced the antinociceptive activity of L-NAME when given in combination. However TDFME co-administration did not produce significant results with methylene blue indicating lack of cGMP involvement. These results indicate that TDFME produces anti-nociception action mediated by opioid, nitric oxide, K+-ATP and glutamate mechanisms and the effect is largely related to the indole alkaloids.
Assuntos
Analgésicos/farmacologia , Flores/química , Alcaloides Indólicos/farmacologia , Metanol/química , Extratos Vegetais/farmacologia , Tabernaemontana/química , Animais , Relação Dose-Resposta a Droga , Masculino , CamundongosRESUMO
In view of the report on anti-nociceptive activity of Leathery Murdah, Terminalia coriacea {Roxb.} Wight & Arn. (Combretaceae) leaves, the present study was conducted to isolate the active constituents and identify the underlying mechanisms. The methanolic extract of T. coriacea leaves (TCLME) at doses 125, 250 and 500â¯mg/kg orally, was subjected to various in-vivo assays in acetic acid induced writhing and formalin induced paw-licking tests with aspirin (100â¯mg/kg) and morphine (5â¯mg/kg) as reference drugs. Three flavonoids, rutin, robinin and gossypetin 3-glucuronide 8-glucoside were isolated and characterized from TCLME for the first time. The extract showed significant (pâ¯<â¯0.001) dose-dependent anti-nociceptive activity in glutamate induced paw licking in mice. The involvement of opioid pathway was confirmed as naloxone (5â¯mg/kg, i.p) treatment blocked the analgesic activity of the test extract. Similarly, glibenclamide (an ATP - sensitive potassium channel inhibitor) at dose of 10â¯mg/kg, i.p increased writhing in acetic acid model. It reversed the inhibitory effects of TCLME when administered in combination. Treatment of TCLME alone and in combination with l-arginine (100â¯mg/kg, i.p) significantly (pâ¯<â¯0.001) reduced writhing while pre-treatment with l-NAME (20â¯mg/kg, i.p) further enhanced the analgesic action of TCLME indicating involvement of nitric oxide pathway.
Assuntos
Analgésicos/farmacologia , Flavonoides/farmacologia , Metanol/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Terminalia/química , Animais , Relação Dose-Resposta a Droga , Glibureto/farmacologia , Canais KATP/antagonistas & inibidores , Masculino , Camundongos , Peptídeos Opioides/metabolismo , Manejo da Dor/métodos , Extratos Vegetais/químicaRESUMO
A new series of 1-phenyl-3-(4-(pyridin-3-yl)phenyl)urea derivatives were synthesized and subjected to in vitro antiproliferative screening against National Cancer Institute (NCI)-60 human cancer cell lines of nine different cancer types. Fourteen compounds 5a-n were synthesized with three different solvent exposure moieties (4-hydroxylmethylpiperidinyl and trimethoxyphenyloxy and 4-hydroxyethylpiperazine) attached to the core structure. Substituents with different π and σ values were added on the terminal phenyl group. Compounds 5a-e with a 4-hydroxymethylpiperidine moiety showed broad-spectrum antiproliferative activity with higher mean percentage inhibition values over the 60-cell line panel at 10 µM concentration. Compound 5a elicited lethal rather than inhibition effects on SK-MEL-5 melanoma cell line, 786-0, A498, RXF 393 renal cancer cell lines, and MDA-MB-468 breast cancer cell line. Two compounds, 5a and 5d showed promising mean growth inhibitions and thus were further tested at five-dose mode to determine median inhibitory concentration (IC50) values. The data revealed that urea compounds 5a and 5d are the most active derivatives, with significant efficacies and superior potencies than paclitaxel in 21 different cancer cell lines belonging particularly to renal cancer and melanoma cell lines. Moreover, 5a and 5d had superior potencies than gefitinib in 38 and 34 cancer cell lines, respectively, particularly colon cancer, breast cancer and melanoma cell lines.
Assuntos
Antineoplásicos , Proliferação de Células/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Compostos de Fenilureia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Compostos de Fenilureia/síntese química , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologiaRESUMO
ABSTRACT BACKGROUND Leathery Murdah, Terminalia coriacea (Roxb.) Wight & Arn. from family Combretaceae is used in Ayurveda and Siddha traditional systems of medicine to heal ulcers. OBJECTIVE The present study was conducted to assess the gastroprotective effect and understand the fundamental mechanism of action of Leathery Murdah, Terminalia coriacea (Roxb.) Wight & Arn. Leaf Methanolic Extract. METHODS The test extract was screened for anti-ulcer activity by Aspirin induced ulcerogenesis in pyloric ligation and ethanol induced gastric ulcers at three doses - 125, 250, and 500 mg/kg, p.o. using Ranitidine 50 mg/kg and Misoprostol 100 μg/kg as standard drug in respective models. Seven parameters were carefully examined, that is, ulcer index, total protein, mucin, catalase, malondialdehyde, and superoxide dismutase levels and histopathology. High Performance Liquid Chromatographic - Ultra Violet profiling and Liquid Chromatography - Mass Spectral analysis of crude Terminalia coriacea leaves methanolic extract were carried out as a part of chemical characterization to identify bioactive compounds. RESULTS All the test doses exhibited significant gastroprotective function, particularly the higher doses demonstrated improved action. The results revealed a significant increase in the levels of catalase, superoxide dismutase, and Mucin with reduction in ulcer index, the levels of total protein, and malondialdehyde. Histopathological observations also illustrated the gastroprotective effect of Terminalia coriacea leaves methanolic extract. CONCLUSION Terminalia coriacea leaves methanolic extract exhibited strong anti-oxidant and anti-secretory activities mediated gastroprotection besides inducing the gastric mucosal production. The observed pharmacological response can be attributed to the flavonoidal compounds namely - Quercetin-3-O-rutinoside, Luteolin-7-O-glucoside, Myricetin hexoside, Quercetin-3-O-glucoside, Isorhamnetin-3-O-rhamnosylglucoside and Isorhamnetin-3-O-glucoside identified in the extract for the first time with High Performance Liquid Chromatographic - Ultra Violet and Liquid Chromatography - Mass Spectral analysis.
RESUMO CONTEXTO Leathery Murdah, Terminalia coriacea (Roxb.) Wight & Arn. da família Combretaceae é usada nos tradicionais sistemas da medicina Ayurveda e Siddha para cicatrização de úlceras. OBJETIVOS O presente estudo foi realizado para avaliar o efeito gastroprotetor e para esclarecer o mecanismo fundamental da ação do extrato metanólico de folhas de Leathery Murdah, Terminalia coracea (Roxb.) Wight & Arn. MÉTODOS O extrato teste foi testado para ação antiulcerogênica induzida pela Aspirina através da ligação pilórica e úlceras gástricas induzidas por etanol em três doses - 125, 250 e 500 mg/kg, via oral, utilizando-se Ranitidina 50 mg/kg e Misoprostol 100 μg/kg como drogas padrão nos respectivos modelos. Sete parâmetros foram cuidadosamente analisados tais como índice ulcerogênico, níveis de proteínas totais, de mucina, de catalase, de malondialdeído e de superoxido dismutase, além da histopatologia. A análise do perfil espectroscópico pela Cromatografia Líquida de Alta Eficiência - Ultravioleta e análise crua pela Cromatografia Líquida - Espectrometria de Massas foram realizadas como parte da caracterização química para identificar os componentes bioativos. RESULTADOS Todas as doses utilizadas exibiram função gastroprotetora, em particular as doses mais elevadas. Os testes revelaram aumentos significantes de catalase, superóxido dismutase e mucina, com diminuição do índice ulcerogênico, dos níveis de proteínas totais, e de malondialdeído. As observações histopatológicas também ilustraram o efeito gastroprotetor do extrato metanólico de folhas de Terminalia coracea. CONCLUSÃO O extrato metanólico de folhas de Terminalia coracea mostrou forte atividade antioxidante e antissecretória além de induzir a produção de mucosa gástrica. A resposta farmacológica observada pode ser atribuída aos compostos flavonoides denominados Quercetin-3-O-rutinosideo, Luteolin-7-O-glucosideo, Myricetin hexosideo, Quercetin-3-O-glucosideo, Isorhamnetin-3-O-rhamnosylglucosideo e Isorhamnetin-3-O-glucosideo, identificados no extrato pela primeira vez pelas análises de Cromatografia Líquida de Alta Eficiência - Ultravioleta e Cromatografia Líquida - Espectrometria de Massas.
Assuntos
Animais , Masculino , Ratos , Úlcera Gástrica/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Terminalia/química , Antiulcerosos/administração & dosagem , Úlcera Gástrica/induzido quimicamente , Anti-Inflamatórios não Esteroides , Aspirina , Ratos Wistar , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mucosa Gástrica/efeitos dos fármacosRESUMO
BACKGROUND: Leathery Murdah, Terminalia coriacea (Roxb.) Wight & Arn. from family Combretaceae is used in Ayurveda and Siddha traditional systems of medicine to heal ulcers. OBJECTIVE: The present study was conducted to assess the gastroprotective effect and understand the fundamental mechanism of action of Leathery Murdah, Terminalia coriacea (Roxb.) Wight & Arn. Leaf Methanolic Extract. METHODS: The test extract was screened for anti-ulcer activity by Aspirin induced ulcerogenesis in pyloric ligation and ethanol induced gastric ulcers at three doses - 125, 250, and 500 mg/kg, p.o. using Ranitidine 50 mg/kg and Misoprostol 100 µg/kg as standard drug in respective models. Seven parameters were carefully examined, that is, ulcer index, total protein, mucin, catalase, malondialdehyde, and superoxide dismutase levels and histopathology. High Performance Liquid Chromatographic - Ultra Violet profiling and Liquid Chromatography - Mass Spectral analysis of crude Terminalia coriacea leaves methanolic extract were carried out as a part of chemical characterization to identify bioactive compounds. RESULTS: All the test doses exhibited significant gastroprotective function, particularly the higher doses demonstrated improved action. The results revealed a significant increase in the levels of catalase, superoxide dismutase, and Mucin with reduction in ulcer index, the levels of total protein, and malondialdehyde. Histopathological observations also illustrated the gastroprotective effect of Terminalia coriacea leaves methanolic extract. CONCLUSION: Terminalia coriacea leaves methanolic extract exhibited strong anti-oxidant and anti-secretory activities mediated gastroprotection besides inducing the gastric mucosal production. The observed pharmacological response can be attributed to the flavonoidal compounds namely - Quercetin-3-O-rutinoside, Luteolin-7-O-glucoside, Myricetin hexoside, Quercetin-3-O-glucoside, Isorhamnetin-3-O-rhamnosylglucoside and Isorhamnetin-3-O-glucoside identified in the extract for the first time with High Performance Liquid Chromatographic - Ultra Violet and Liquid Chromatography - Mass Spectral analysis.
Assuntos
Antiulcerosos/administração & dosagem , Extratos Vegetais/administração & dosagem , Úlcera Gástrica/tratamento farmacológico , Terminalia/química , Animais , Anti-Inflamatórios não Esteroides , Aspirina , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mucosa Gástrica/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamenteRESUMO
Channa striata (Bloch.) is a fresh water fish belonging to the family Channidae. The stripped snakehead fish possesses wide range of medicinal properties. In view of traditional use of C. striata for wound healing, the present study was undertaken to investigate the beneficial effects of orally administered freeze dried aqueous extract of Channa striata (AECS) in experimentally induced gastric ulcers in Wistar rats. Aspirin induced ulcerogenesis in pyloric ligation model was used for the assessment of antiulcer activity and Ranitidine (50 mg/kg) was employed as the standard drug. The various gastric parameters like volume of gastric juice, pH, free and total acidities, ulcer index, and levels of antioxidant enzymes like catalase, superoxide dismutase, and lipid peroxidation marker malondialdehyde were determined. AECS at concentrations of 40% and 50% w/v significantly decreased the volume of gastric juice and increased the levels of catalase while considerable decrease in free and total acidities and increase in superoxide dismutase were observed with the treatment of standard drug and AECS (50% w/v). All the test doses of AECS markedly decreased ulcer index and malondialdehyde compared to the standard drug whereas AECS 30% w/v did not alter volume of gastric juice, pH, free and total acidities, catalase, and superoxide dismutase. From these findings, it can be concluded that AECS is devoid of acid neutralizing effects at lower doses and possesses antisecretory and antiulcer activities and this could be related to its antioxidant mechanism.
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The present study was conducted to evaluate the antiulcerogenic effect and recognize the basic mechanism of action of Tabernaemontana divaricata (L.) R. Br. flowers. T. divaricata flower methanolic extract (TDFME) was screened for antiulcer activity versus aspirin and ethanol induced gastric ulcers at three doses--125, 250, and 500 mg/kg--orally using misoprostol as a standard. Besides histopathological examination, seven parameters, that is, ulcer index, total protein, nonprotein sulphhydryls, mucin, catalase, malondialdehyde, and superoxide dismutase levels, were estimated. In addition to HPLC profiling, GC-MS analysis and electrospray ionization--high resolution mass spectral (ESI-HRMS) analysis of crude TDFME were carried out in an attempt to identify known phytochemicals present in the extract on the basis of m/z value. The results revealed a significant increase in the levels of catalase, superoxide dismutase, mucin, and nonprotein sulphhydryls, while they revealed a reduction in ulcer index, the levels of total protein, and malondialdehyde. Histopathological observations also demonstrated the protective effect. Though all the doses of TDFME exhibited gastroprotective function, higher doses were found to be more effective. Mass spectral analysis gave a few characteristic m/z values suggesting the presence of a few known indole alkaloids, while HPLC profiling highlighted the complexity of the extract. TDFME was found to exhibit its gastroprotective effect through antioxidant mechanism and by enhancing the production of gastric mucous.
Assuntos
Antioxidantes/farmacologia , Flores/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prostaglandinas/farmacologia , Úlcera Gástrica/tratamento farmacológico , Tabernaemontana/química , Animais , Antioxidantes/química , Aspirina/efeitos adversos , Catalase/metabolismo , Etanol/efeitos adversos , Masculino , Malondialdeído/metabolismo , Metanol/química , Mucinas/metabolismo , Prostaglandinas/química , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/metabolismo , Superóxido Dismutase/metabolismoRESUMO
Sandalwood (Santalum album L.) is used in various traditional systems of medicine, like Ayurveda, Siddha and Unani medicine to treat a wide range of ailments. In Unani medicine, Safed Sandal is used to treat gastric ulcers, hence the present study was undertaken to confirm this claim. A limit test as per OECD guidelines was conducted at a dose of 5000 mg/kg to determine the acute toxic dose of Hydro-alcoholic extract from S. album stem (SASE). Two test doses of SASE (250 and 500 mg/kg) were subjected to screening of anti-ulcer activity by three in-vivo models namely water immersion - restrain stress, ethanol and indomethacin induced gastric ulceration models in albino wistar rats. A proton-pump inhibitor, Omeprazole 10 mg/kg and H2 receptor antagonist, Ranitidine 50 mg/kg were employed as standard drugs. The results revealed an increase in gastric protection as a significant decrease (p < 0.001) in average number of ulcers, severity of ulcers and cumulative ulcer index was observed in the test groups. Histopathological evidences supported the above findings. The observed anti-ulcer effect of SASE at 500 mg/kg was comparable to that of standard drugs used in the experiments indicating significant anti-ulcer potential especially at higher concentration.
Sándalo (Santalum album L.) se utiliza en diversos sistemas de medicina tradicional, como el Ayurveda, Siddha y Unani para tratar una amplia gama de dolencias. En la medicina Unani, Safed Sandal se usa para tratar úlceras gástricas, por lo tanto, el presente estudio se realizó para confirmar esta afirmación. Una prueba de límite según las directrices de la OCDE se llevó a cabo a una dosis de 5000 mg/kg para determinar la dosis tóxica aguda del extracto hidroalcohólico del tallo de S. álbum (SASE). Dos dosis de prueba de SASE (250 y 500 mg/kg) se sometieron al estudio de la actividad anti-úlcera por tres modelos in vivo, a saber: la inmersión en agua estrés de restricción, y la ulceración gástrica inducida por etanol e indometacina, en ratas Wistar albinas. Un inhibidor de la bomba de protones, omeprazol 10 mg/kg y el antagonista de los receptores H2, ranitidina 50 mg/kg fueron empleados como fármacos estándar. Los resultados revelaron un aumento de la protección gástrica como una disminución significativa (p < 0.001) en el número promedio de úlceras, la gravedad de las úlceras y el índice de úlcera acumulativo se observó en los grupos de prueba. Evidencias histopatológicas apoyaron las conclusiones anteriores. El efecto anti úlcera observado por efecto de SASE a 500 mg/kg fue comparable a la de fármacos estándar utilizados en los experimentos que indican un significativo potencial anti-úlcera, especialmente a mayores concentraciones.