Influence of Lycium barbarum Extract Intake on Oxidative Stress in Wistar Rats

Abstract: This study aimed to analyze the effects of Goji Berry extract (GB, Lycium barbarum) gavage administration on liver tissue oxidative stress in Wistar rats as well as to identify and quantify the content of the major bioactive compounds of the fruit. Four diets were applied: SW - standard diet + water; SG - standard diet + Goji Berry extract (125 mg/kg of animal); PW - palatable diet + water; PG - palatable diet + Goji Berry extract (125 mg/kg of animal). Results showed a significant increase in catalase enzyme activity in the liver of rats treated with GB and also in those intaking the palatable diet without GB when compared to the SW group. An increased mRNA expression of this enzyme in the same tissue and groups was also verified. Regarding lipid peroxidation, the GB extract produced a significant decrease in the oxidation state in the SG and PG groups. The results also showed a significant amount of bioactive compounds in GB extract.

Melatonin has a stimulatory effect on osteoblasts by upregulating COL-I and OPN expression/secretion / Melatonina tem efeito estimulador em osteoblastos, pela regulação positiva da expressão/secreção de COL-I e OPN

ABSTRACT Melatonin (MLT) is a potential signaling molecule in the homeostasis of bone metabolism and may be an important mediator of bone formation and stimulation. The aim of this in vitro study was to evaluate the effect of MLT on the viability, mRNA/protein expression and mineralization of pre-osteoblastic cells. The concentrations 5, 2.5, 1, 0.1 and 0.01 mM MLT were tested on pre-osteoblastic cells (MC3T3) compared to control (no MLT), evaluating proliferation and cell viability (C50), gene expression (RT-PCR) and secretion (ELISA) of COL-I and OPN at 24h, 48h and 72h, and the formation of mineral nodules (alizarin red and fast red) after 10 days of treatment. MLT at 5 and 2.5 mM proved to be cytotoxic (C50), so only 0.01, 0.1 and 1 mM were used for the subsequent analyses. OPN mRNA expression increased with MLT at 0.1 mM - 1 mM, which was followed by increased secretion of OPN both at 24h and 72h compared to the remaining groups (p <0.05). COL-I mRNA and COL-1 secretion followed the same pattern as OPN at 0.1 mM MLT at 72h of treatment (p <0.05). Regarding mineralization, all MLT doses (except 1mM) caused an increase (p <0.05) in the formation of mineral nodules compared to the control. Melatonin at 0.01mM - 1mM had a stimulatory effect on osteoblasts by upregulating COL-I and OPN expression/ secretion and mineralization, thereby fostering osteogenesis.

RESUMO A melatonina (MLT) é uma molécula potencial de sinalização na homeostase do metabolismo ósseo e pode ser um importante mediador da formação e estimulação óssea. O objetivo deste estudo in vitro foi avaliar o efeito da MLT na viabilidade, na expressão do mRNA da proteína e mineralização de células préosteoblásticas. As concentrações de MLT 5, 2,5, 1, 0,1 e 0,01 mM foram testadas em células pré-osteoblásticas da linhagem MC3T3 em comparação ao controle (sem MLT), avaliando a proliferação e a viabilidade celular (C50), expressão gênica (rtPCR) e secreção (Elisa) de Colágeno tipo 1 (COL-I) e osteopontina (OPN) às 24, 48 e 72 horas, além da formação de nódulos minerais por meio do teste vermelho de Alizarina fast red após 10 dias de tratamento. MLT a 5 e 2,5 mM provou ser tóxico (C50). Portanto, as concentrações de 0,01, 0,1 e 1 mM foram utilizadas para as análises subsequentes. A expressão do mRNA da OPN aumentou com MLT a 0,1 mM-1mM, seguida pela secreção aumentada de OPN às 24 e 72 horas em comparação aos demais grupos (p<0,05). O mRNA de COL-I e a secreção de COL-I seguiram o mesmo padrão do OPN a 0,1 mM de MLT em 72 horas de tratamento (p<0,05). Em relação à mineralização, todas as doses de MLT (exceto 1mM) causaram aumento (p<0,05) na formação de nódulos minerais em comparação ao controle. A MLT na concentração entre 0,01mM a 1 mM teve um efeito estimulador sobre os osteoblastos, ao regular positivamente a expressão e secreção de COL-I e OPN, além da mineralização, favorecendo a osteogênese.

Anti-inflammatory Effect of a Goji Berry Extract (Lycium barbarum) in Rats Subjected to Inflammation by Lipopolysaccharides (LPS)

Abstract The present study aimed to evaluate the anti-inflammatory potential of a Lycium barbarum (L. barbarum) fruit extract in Wistar rats submitted to a palatable diet presenting systemic inflammation induced by lipopolysaccharides (LPS). Forty-two Wistar female rats (Rattus Novergicus) were used with 60 days old. The animals were feed for 60 days and divided in six groups (n=7): standard diet+water; standard diet+L. barbarum; palatable diet+water; palatable diet+L. barbarum; standard diet+water+LPS; standard diet+L. barbarum+LPS. A significant difference was shown between the analyzed groups concerning C-reactive protein, with the standard diet+water+LPS group presenting the highest inflammatory response in comparison to the other groups. Decreased inflammatory response was observed in the group administered a palatable diet along with the fruit extract when compared to the group that received only a palatable diet. Significant decrease in glutamic-oxaloacetic transaminase activity was observed in the standard diet+L. barbarum+LPS group compared to the standard diet+water group, as well as in the palatable diet+L. barbarum group compared to the palatable diet+water group. A significant increase in creatinine in the standard diet+water+LPS group was observed in according to the L. barbarum administration groups. The gene expression of the inflammatory markers genes in the liver showed a significant increase in TNF-α and IL-6 genes in the group treated with standard diet+L. barbarum+LPS when compared to the standard diet+LPS group. Thus, the administered L. barbarum extract displays the potential to reduce inflammatory responses induced by LPS and a palatable diet.