ECa 233 Suppresses LPS-Induced Proinflammatory Responses in Macrophages via Suppressing ERK1/2, p38 MAPK and Akt Pathways.

A current anti-inflammatory agent often targets the prevention of inflammatory disorder development. The standardized Centella asiatica ECa 233 extract has been previously reported for anti-inflammatory effect. This study aimed to investigate its anti-inflammatory effect and mechanisms of ECa 233 in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages, through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, nitric oxide (NO) assay, reactive oxygen species (ROS) production assay, enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. Our results found that ECa 233 significantly inhibited LPS-stimulated pro-inflammatory mediators production including ROS, NO and prostaglandin E2 (PGE2), and pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α and interleukin (IL)-1ß without cytotoxicity. In addition, ECa 233 downregulated not only the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), but also the activation of nuclear factor-kappa B (NF-κB), activated protein kinase B (Akt), extracellular signal-regulated kinase (ERK1/2) and p38 mitogen-activated protein kinases (MAPK) induced by LPS. The inhibition of LPS-induced inflammation due to ECa 233 offered an opportunity as a tentatively potential candidate for the prevention and treatment of inflammatory diseases.

Metformin Promotes Neuronal Differentiation via Crosstalk between Cdk5 and Sox6 in Neuroblastoma Cells.

Metformin has recently emerged as a key player in promotion of neuroblastoma differentiation and neurite outgrowth. However, molecular mechanisms of how metformin promotes cellular differentiation have not yet been fully elucidated. In this study, we investigated how metformin promotes cell differentiation, via an inhibition of cell proliferation, by culturing SH-SY5Y neuroblastoma cells with or without metformin. Pretreatment with reactive oxygen species (ROS) scavenger, NAC, revealed that ROS plays a crucial role in induction of cell differentiation. Cell differentiation was observed under various morphological criteria: extension of neuritic processes and neuronal differentiation markers. Treatment with metformin significantly increased neurite length, number of cells with neurite, and expression of neuronal differentiation markers, ß-tubulin III and tyrosine hydroxylase (TH) compared with untreated control. Further investigation found that metformin significantly decreased Cdk5 but increased Sox6 during cell differentiation. Analysis of the mechanism underlying these changes using Cdk5 inhibitor, roscovitine, indicated that expressions of Cdk5 and Sox6 corresponded to metformin treatment. These results suggested that metformin produces neuronal differentiation via Cdk5 and Sox6. In addition, phosphorylated Erk1/2 was decreased while phosphorylated Akt was increased in metformin treatment. Taken together, these findings suggest that metformin promotes neuronal differentiation via ROS activation through Cdk5/Sox6 crosstalk, relating to Erk1/2 and Akt signaling.

Induction of keratinocyte migration by ECa 233 is mediated through FAK/Akt, ERK, and p38 MAPK signaling.

Centella asiatica is widely considered the most important medicinal plant for treating and relieving skin diseases. Recently developed standardized extract of Centella asiatica ECa 233 has demonstrated positive effects on wound healing of incision and burn wound in rats. However, knowledge associated with wound healing mechanism of ECa 233 was scare. Therefore, this study aimed to investigate the effect and underlying molecular mechanisms of ECa 233 on the migration of a human keratinocyte cell line (HaCaT) using scratch wound healing assay. Formation of filopodia, a key protein in cell migration as well as signaling pathways possibly involved were subsequently assessed. It was found that HaCaT cell migration was significantly enhanced by ECa 233 in a concentration- and time-dependent manner. The filopodia formations were accordingly increased in exposure to ECa 233 at concentrations of 0.1-100 µg/ml. Furthermore, ECa 233 was found to significantly upregulate the expression of Rac1 and RhoA and to induce phosphorylation of FAK and Akt as well as ERK and p38 MAPK. Taken all together, it is suggestive that ECa 233 induces cell migration and subsequently promotes wound healing activity, through the activation of FAK, Akt, and MAPK signaling pathways thereby supporting the role of ECa 233 to be further developed for the clinical treatment of wound.

Apium graveolens extract influences mood and cognition in healthy mice.

Apium graveolens is a food flavoring which possesses various health promoting effects. This study investigates the effect of a sub-acute administration of A. graveolens on cognition and anti-depression behaviors via antioxidant and related neurotransmitter systems in mice brains. Cognition and depression was assessed by various models of behavior. The antioxidant system of glutathione peroxidase (GPx), % inhibition of superoxide anion (O2-), and lipid peroxidation were studied. In addition, neurochemical parameters including acetylcholinesterase (AChE) and monoamine oxidase-type A (MAO-A) were also evaluated. Nine groups of male mice were fed for 30 days with different substances-a control, vehicle, A. graveolens extract (65-500 mg/kg), and reference drugs (donepezil and fluoxetine). The results indicated that the effect of the intake of A. graveolens extract (125-500 mg/kg) was similar to the reference drugs, as it improved both spatial and non-spatial memories. Moreover, there was a decrease in immobility time in both the forced swimming and tail suspension tests. In addition, the A. graveolens extract reduced lipid peroxidation of the brain and increased GPx activity and the % inhibition of O2-, whereas the activities of AChE and MAO-A were decreased. Thus, our data have shown that the consumption of A. graveolens extract improved cognitive function and anti-depression activities as well as modulating the endogenous antioxidant and neurotransmitter systems in the brain, resulting in increased neuronal density. This result indicated an important role for A. graveolens extract in preventing age-associated decline in cognitive function associated with depression.

Effects of Apium graveolens Extract on the Oxidative Stress in the Liver of Adjuvant-Induced Arthritic Rats.

Apium graveolens Linn. (Apiaceae) is an indigenous plant of the North and South Americas, Southern Europe, and Asia and has been widely used as a food or a traditional medicine for treatment of inflammation and arthritis. The purpose of this study was to investigate the antioxidant effects of a methanolic extract of A. graveolens (AGE) against liver oxidative stress in an adjuvant-induced arthritic rat model. The AGE (250, 500, and 1,000 mg/kg) was given orally for 24 consecutive days after induction by injecting complete Freund's adjuvant. Liver and spleen weights were recorded. The superoxide anion level, total peroxide (TP), glutathione peroxidase (GPx) activity, superoxide dismutase (SOD) activity, total antioxidant status, and oxidative stress index (OSI) were also measured. AGE treatment significantly decreased the levels of the superoxide anion, TP, and OSI whereas the GPx and SOD activities significantly increased in the liver of the arthritic rats. These results indicated that AGE showed an ameliorative effect against liver oxidative stress in adjuvant-induced arthritic rats by reducing the generation of liver free radicals and increasing the liver antioxidant enzyme activity.