The antioxidant activity of lemongrass leaves extract against fibroblasts oxidative stress / Atividade antioxidante do extrato das folhas de capim-limão contra o estresse oxidativo em fibroblastos

Objective : The purpose of this research is to assess the antioxidant activity of lemongrass leaves extract in terms of lowering ROS generation and its effect on the viability and proliferation of fibroblasts under oxidative stress. Material and Methods: The antioxidant activity was measured using the DPPH method and the ROS assay was carried out by fluorescent H2DCFDA staining. Viability and proliferation assays were performed using the Cell Counting Kit-8 (CCK-8) and was read at 450 nm using microplate reader. The groups were divided into 8, namely fibroblasts without treatment (comparison group), fibroblast induced by H2O2 (negative control), fibroblast with H2O2 then treated with ascorbic acid (positive control), and fibroblast with H2O2 then treated with lemongrass leaves extract at various concentrations (10, 20, 30, 40, and 50 ppm). Results: The results showed that the antioxidant activity of lemongrass leaves extract had an IC value of 64.17 ppm. ROS production were reduced by the LgLE of all concentrations if compared with negative control (p=0.819). LgLE can maintained the fibroblast viability with 10 ppm of LgLE was the most optimum concentration (p<0.05). LgLE can induced the proliferation of fibroblast, with the most effective was at 24 h of observation (p<0.05). Conclusion: Lemongrass leaves extract has a strong antioxidant activity that can reduce oxidative stress and increase the viability and proliferation of fibroblasts with the optimum concentration is at 10 ppm. (AU)

Objetivo: O intuito deste estudo foi determinar a ação antioxidante do extrato das folhas de capim-limão no que se refere a diminuição da produção de espécies reativas do oxigênio (EROS) e o seu efeito na viabilidade e proliferação de fibroblastos submetidos à estresse oxidativo. Material e Métodos: A atividade antioxidante foi medida utilizando o método de DPPH e o ensaio de EROS foi realizado pela coloração fluorescente de H2DCFDA. Os ensaios de proliferação e viabilidade foram realizados utilizando-se o kit de contagem de células CCK-8 em microplacas de leitura à 450nm. Os grupos foram divididos em 8: Fibroblastos sem tratamento (grupo controle), Fibroblastos tratados com H2O2 (controle negativo), Fibroblastos tratados com H2O2 e extrato da folha de capim-limão em concentrações variadas (10, 20, 30, 40 e 50 ppm). Resultados: Os resultados mostraram que a atividade antioxidante do extrato de capim-limão teve uma IC50 (com o numeroal subscrito) com valor de 64.17ppm. A produção de ROS foi reduzida pelo tratamento com o extrato em todas as concentrações testadas quando comparado ao grupo controle negativo (p=0.819). O extrato manteve a viabilidade dos fibroblastos, sendo 10ppm a concentração menos tóxica (p<0.05). LgLE pôde induzir a proliferação de fibroblastos, sendo que a melhor eficiencia foi após 24h de observação (p<0.05). Conclusão: O extrato das folhas de capim-limão apresentam forte atividade antioxidante reduzindo o estresse oxidativo e aumentando a viabilidade e proliferação de fibroblastos, sendo a concentração ótima de 10ppm. (AU)

Genotype selection for phytochemical content and pharmacological activities in ethanol extracts of fifteen types of Orthosiphon aristatus (Blume) Miq. leaves using chemometric analysis.

Orthosiphon aristatus (Blume) Miq. of the Lamiaceae family, called as kumis kucing in Indonesia, is a valuable medicinal plant for their pharmacological properties. The present study comprised of fifteen genotypes of O. aristatus was undertaken to evaluate the genotypes based on phytochemical content and pharmacological activities of leaves ethanol extract. Chemometric analysis (correlation and principal component analysis) was also used to investigate the genetic variability based on phytochemical content and pharmacological activities of O. aristatus genotypes. Results of phytochemical characterization showed that total phenolic ranged from 1.48 to 36.08 (maximum in A15) mg GAE/g DW, total flavonoid ranged from 0.10 to 3.07 (maximum in A15) mg QE/g DW, sinensetin ranged from 0.36 to 4.02 (maximum in A11) mg/g DW, and rosmarinic acid ranged 0.06 to 7.25 (maximum in A7) mg/g DW. Antioxidant activity was tested using DPPH and FRAP assay. Antioxidant results showed that DPPH ranged from 1.68 to 15.55 (maximum in A15) µmol TE/g DW and FRAP ranged from 0.07 to 1.60 (maximum in A1 and A7) µmol TE/g DW. The genotype A8 showed the highest cytotoxic activities against HeLa (66.25%) and MCF-7 (61.79%) cell lines. Maximum α-glucosidase inhibitory activity was recorded in genotype A2 with the value of 62.84%. The genotypes A1, A2, A7, A11, and A15 were identified as superior based on their phytochemicals content and pharmacological activities coupled with chemometric analysis. This finding is important for breeding studies and also the pharmaceutical perspective of O. aristatus.

Valproic Acid Exposure of Pregnant Rats During Organogenesis Disturbs Pancreas Development in Insulin Synthesis and Secretion of the Offspring.

Valproic acid (VPA) plays a role in histone modifications that eventually inhibit the activity of histone deacetylase (HDAC), and will affect the expressions of genes Pdx1, Nkx6.1, and Ngn3 during pancreatic organogenesis. This experiment was designed to study the effect of VPA exposure in pregnant rats on the activity of HDAC that controls the expression of genes regulating the development of beta cells in the pancreas to synthesize and secrete insulin. This study used 30 pregnant Sprague-Dawley rats, divided into 4 groups, as follows: (1) a control group of pregnant rats without VPA administration, (2) pregnant rats administered with 250 mg VPA on day 10 of pregnancy, (3) pregnant rats administered with 250 mg VPA on day 13 of pregnancy, and (4) pregnant rats administered with 250 mg VPA on day 16 of pregnancy. Eighty-four newborn rats born to control rats and rats administered with VPA on days 10, 13, and 16 of pregnancy were used to measure serum glucose, insulin, DNA, RNA, and ratio of RNA/DNA concentrations in the pancreas and to observe the microscopical condition of the pancreas at the ages of 4 to 32 weeks postpartum with 4-week intervals. The results showed that at the age of 32 weeks, the offspring of pregnant rats administered with 250 mg VPA on days 10, 13, and 16 of pregnancy had higher serum glucose concentrations and lower serum insulin concentrations, followed by decreased concentrations of RNA, and the ratio of RNA/DNA in the pancreas. Microscopical observations showed that the pancreas of the rats born to pregnant rats administered with VPA during pregnancy had low immunoreaction to insulin. The exposure of pregnant rats to VPA during pregnancy disturbs organogenesis of the pancreas of the embryos that eventually disturb the insulin production in the beta cells indicated by the decreased insulin secretion during postnatal life.