RESUMO
Ethnopharmacobotanical information reports that Parkinsonia aculeata infusion is used to control diabetes-related complications and dyslipidemia. However, few studies are reported on the safe use of this species. The aim of this study is to evaluate the acute toxicity, embryotoxicity and cytotoxicity of a polar fraction obtained from hydroethanolic extract of P. aculeata (PfrHEPA). For the acute toxicity test, we considered the Up and Down method which the guidelines are described by the Organization for Economic Cooperation and Development (OECD N°425). The animals were treated with PfrHEPA (2000 mg/kg) or with distilled water (10 ml/kg) by gavage and observed from Day 1 to14. For embryotoxicity assay, zebrafish embryos were exposed to PfrHEPA (100 mg/L) and toxicity parameters were observed during four consecutive days. The cytotoxicity of PfrHEPA (5, 10, 25, 50, 75 and 100 µg/ml, respectively) was performed on normal cell lines (mesenchymal stem cells, African green monkey renal cells and mouse pre-adipocytes 3 T3-L1 using the MTT salt reduction assay. In the acute toxicity test, no mortality was observed in mice treated with PfrHEPA (2000 mg/kg), as well as behavioral changes, histopathological abnormalities and hematological and biochemical variables. In the embryotoxicity test, no abnormal changes related to the toxicological parameters were observed in the period of 96 h. Regarding the cytotoxicity assay, PfrHEPA showed no cytotoxic effect on the normal cell lines tested, with an IC50 value > 100 µg/ml. These results suggest the safe use of P. aculeata, however, more trials are needed for PfrHEPA to be presented as new safe therapeutic proposal for the control of metabolic disorders.
RESUMO
Introduction: Since photobiomodulation therapy (PBMT) favors in vitro mesenchymal stem cell (MSC) preconditioning before MSC transplantation, increasing the proliferation of these cells without molecular injuries by conserving their characteristics, in the present in vitro study we analyzed the effect of PBMT on the proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs). Methods: Irradiation with an InGaAIP Laser (660 nm, 10 mW, 2.5 J/cm2 , 0.08 cm2 spot size, and 10 s) was carried out. The cells were divided into four groups: CONTROL [cells grown in Dulbecco's Modified Eagle Medium (DMEM)], OSTEO (cells grown in an osteogenic medium); PBMT (cells grown in DMEM+PBMT), and OSTEO+PBMT (cells grown in an osteogenic medium plus PBMT). The cell proliferation curve was obtained over periods of 24, 48 and 72 hours using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Osteogenic differentiation was analyzed by the formation of calcium nodules over periods of 7, 14 and 21 days. Morphometric analysis was performed to quantify the total area of nodular calcification. Results: The highest cell proliferation and cell differentiation occurred in the OSTEO+PBMT group, followed by the PBMT, OSTEO and CONTROL groups respectively, at the observed times (P <0.05). Conclusion: PBMT enhanced the osteogenic proliferation and the differentiation of hUCMSCs during the periods tested, without causing damage to the cells and preserving their specific characteristics, a fact that may represent an innovative pretreatment in the application of stem cells.
