Hippeastrum elegans is a Brazilian Amaryllidaceae plant producing galantamine (GAL), an anticholi... more Hippeastrum elegans is a Brazilian Amaryllidaceae plant producing galantamine (GAL), an anticholinesterase drug for Alzheimer's disease, besides other alkaloids such as pseudolycorine (PSE), narciclasine (NAR) and sanguinine (SAN). Therefore, we used a metabolomic approach to investigate the influence of the harvest time on its chemical composition and acetylcholinesterase activity (AChE). Alkaloid extracts were analyzed by UPLC-ESI-MS and 1H NMR, then assessed for AChE inhibitory activity. These data were combined and analyzed by Partial Least Square (PLS) regression. H. elegans was found to be rich in PSE and NAR, achieving higher contents in 270 and 390 days of cultivation, respectively. However, the highest anti-AChE activities were observed for 450 days-bulbs extracts. PLS indicated pseudolycorine as the discriminant compound for this extract, hence responsible for its higher anti-AChE activity jointly with the known AChE inhibitors GAL and SAN. Thus, the cultivation of H. ...
A malaria e uma doenca infecciosa ocasionada pelo protozoario do genero Plasmodim, sendo as princ... more A malaria e uma doenca infecciosa ocasionada pelo protozoario do genero Plasmodim, sendo as principais especies o P. vivax e o P. falciparum, responsaveis por cerca de 198 milhoes de casos e causando milhao de mortes anualmente. A resistencia do parasito aos antimalaricos usuais e as limitacoes existentes no combate ao vetor sao implicacoes que contribuem para a expansao dessa parasitose. O objetivo desse estudo foi testar a atividade antimalarica e toxicidade in vivo, viabilidade celular em celulas Hep-G2, atividade hemolitica e atividade antioxidante do composto 3,4-Dihidroxibenzaldeido. A atividade antimalarica in vivo nao foi satisfatoria nas doses testadas, porem o composto nao apresentou toxidade na dose maxima de 2000 mg/kg in vivo, nem atividade hemolitica in vitro. A viabilidade celular in vitro contra linhagem de celulas Hep-G2 apresentou a IC50 de 440,5 ± 50,8 μg/mL e a atividade antioxidante foi de 95,6%. Embora sejam dados preliminares, este composto e um candidato prom...
The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifol... more The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifolium was evaluated as a neuroprotective agent in the intracerebroventricular (icv) pilocarpine (Pilo) model. To this aim, male mice were subdivided into sham (SO, vehicle), Pilo (300 µg/1 µL icv, followed by the vehicle per os, po) and NMP-treated groups (Pilo 300 µg/1 µL icv, followed by 100 or 200 mg/kg po). The treatments started one day after the Pilo injection and continued for 15 days. The effects of NMP were assessed by characterizing the preservation of cognitive function in both the Y-maze and object recognition tests. The hippocampal cell viability was evaluated by Nissl staining. Additional markers of damage were studied—the glial fibrillary acidic protein (GFAP) and the ionized calcium-binding adaptor molecule 1 (Iba-1) expression using, respectively, immunofluorescence and western blot analyses. We also performed molecular docking experiments revealing that NMP binds to the γ...
Hippeastrum elegans is a Brazilian Amaryllidaceae plant producing galantamine (GAL), an anticholi... more Hippeastrum elegans is a Brazilian Amaryllidaceae plant producing galantamine (GAL), an anticholinesterase drug for Alzheimer's disease, besides other alkaloids such as pseudolycorine (PSE), narciclasine (NAR) and sanguinine (SAN). Therefore, we used a metabolomic approach to investigate the influence of the harvest time on its chemical composition and acetylcholinesterase activity (AChE). Alkaloid extracts were analyzed by UPLC-ESI-MS and 1H NMR, then assessed for AChE inhibitory activity. These data were combined and analyzed by Partial Least Square (PLS) regression. H. elegans was found to be rich in PSE and NAR, achieving higher contents in 270 and 390 days of cultivation, respectively. However, the highest anti-AChE activities were observed for 450 days-bulbs extracts. PLS indicated pseudolycorine as the discriminant compound for this extract, hence responsible for its higher anti-AChE activity jointly with the known AChE inhibitors GAL and SAN. Thus, the cultivation of H. ...
A malaria e uma doenca infecciosa ocasionada pelo protozoario do genero Plasmodim, sendo as princ... more A malaria e uma doenca infecciosa ocasionada pelo protozoario do genero Plasmodim, sendo as principais especies o P. vivax e o P. falciparum, responsaveis por cerca de 198 milhoes de casos e causando milhao de mortes anualmente. A resistencia do parasito aos antimalaricos usuais e as limitacoes existentes no combate ao vetor sao implicacoes que contribuem para a expansao dessa parasitose. O objetivo desse estudo foi testar a atividade antimalarica e toxicidade in vivo, viabilidade celular em celulas Hep-G2, atividade hemolitica e atividade antioxidante do composto 3,4-Dihidroxibenzaldeido. A atividade antimalarica in vivo nao foi satisfatoria nas doses testadas, porem o composto nao apresentou toxidade na dose maxima de 2000 mg/kg in vivo, nem atividade hemolitica in vitro. A viabilidade celular in vitro contra linhagem de celulas Hep-G2 apresentou a IC50 de 440,5 ± 50,8 μg/mL e a atividade antioxidante foi de 95,6%. Embora sejam dados preliminares, este composto e um candidato prom...
The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifol... more The N-methyl-(2S,4R)-trans-4-hydroxy-l-proline-enriched fraction (NMP) from Sideroxylon obtusifolium was evaluated as a neuroprotective agent in the intracerebroventricular (icv) pilocarpine (Pilo) model. To this aim, male mice were subdivided into sham (SO, vehicle), Pilo (300 µg/1 µL icv, followed by the vehicle per os, po) and NMP-treated groups (Pilo 300 µg/1 µL icv, followed by 100 or 200 mg/kg po). The treatments started one day after the Pilo injection and continued for 15 days. The effects of NMP were assessed by characterizing the preservation of cognitive function in both the Y-maze and object recognition tests. The hippocampal cell viability was evaluated by Nissl staining. Additional markers of damage were studied—the glial fibrillary acidic protein (GFAP) and the ionized calcium-binding adaptor molecule 1 (Iba-1) expression using, respectively, immunofluorescence and western blot analyses. We also performed molecular docking experiments revealing that NMP binds to the γ...
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