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Vaccinium bracteatum Thunb. Leaves (VBL) are a component of traditional herbal medicines. However, molecular mechanisms of VBL in stress-related memory impairment are still unclear. This study aimed to investigate the spatial memory improvement effects of VBL in an animal model of chronic restraint stress (CRS) by using Y maze test and identified possible protective mechanisms against oxidative stress inducers (e.g., corticosterone and hydrogen peroxide [H2O2]) in SH-SY5Y neuronal cells. VBL showed neuroprotective effects via reduced release of lactate dehydrogenase (LDH) in corticosterone or H2O2-induced cell death that was mediated through the regulation of cleaved caspase-3 and Nrf2 pathways. Furthermore, CRS-exposed mice were orally administered VBL (10, 50, 100, and 200 mg/kg) daily for 21 days. CRS-exposed mice treated with VBL showed significantly increased spontaneous alternation in short-term memory (STM) and long-term memory (LTM) trials, and number of total arm entries in LTM trials as measured by the Y maze test. Moreover, VBL (50, 100, and 200 mg/kg) decreased acetylcholinesterase (AChE) activity in the hippocampus (HC, [Formula: see text] ¡ 0.01 and [Formula: see text] ¡ 0.001, respectively) and prefrontal cortex (PFC). CRS-exposed mice treated with VBL had dramatically decreased total Tau and Tau phosphorylation in the synapse of the HC and PFC which might be mediated by the regulation of CaMKII and GSK3[Formula: see text] phosphorylation. Additionally, VBL reduced CRS-induced upregulation of N-methyl-D-aspartate (NMDA) receptor subunits (NMDAR1, 2A, and 2B). Thus, VBL exerts spatial memory improvement by regulating CRS-induced NMDA receptor neurotoxicity and Tau hyperphosphorylation.

This study was preformed to establish a simple and reliable HPLC/UV analytical method to determine p-coumaric acid contents for the standardization of water extracts of Allium hookeri and Curcuma longa complex as functional health food ingredients. The quantitative HPLC method was optimized using a reversed-phase C18 column at 35°C with methanol and H2O (30:70, v/v) as the gradient mobile phase at a flow rate of 1.0 mL/min and along with detection wavelength of UV 300 nm. This HPLC/UV analytical method exhibited good specificity and high linearity in the tested range of 1.0–10.0 mg/mL with excellent coefficient of determination (R2) of 1.0. The limit of detection and limit of quantification were 0.08 and 0.24 μg/mL, respectively. In addition, the relative standard deviation values from the intra and inter-day precision measurements were 0.4 and 0.1%, respectively. These results indicate that the established HPLC/UV analytical method is simple, specific, precise, accurate, and reproducible and so could be employed in the quantitative analysis of p-coumaric acid as a functional compound in Allium hookeri Thwaites and Curcuma longa complex.

Background Quercus acuta Thunb. (Fagaceae) or Japanese evergreen oak is cultivated as an ornamental plant in South Korea, China, Japan, and Taiwan and used in traditional medicine. The acorn or fruit of Quercus acuta Thunb. (QAF) is the main ingredient of acorn jelly, a traditional food in Korea. Its leaf was recently shown to have potent xanthine oxidase inhibitory and anti-hyperuricemic activities; however, there have been no studies on the biological activity of QAF extracts. Solar ultraviolet light triggers photoaging of the skin, which increases the production of reactive oxygen species (ROS) and expression of matrix metalloproteinase (MMPs), and destroys collagen fibers, consequently inducing wrinkle formation. The aim of this study was to investigate the effect of water extracts of QAF against UVB-induced skin photoaging and to elucidate the underlying molecular mechanisms in human keratinocytes (HaCaT). Methods In this study, we used HPLC to identify the major active components of QAF water extracts. Anti-photoaging effects of QAF extracts were evaluated by analyzing ROS procollagen type I in UVB-irradiated HaCaT keratinocytes. Antiradical activity was determined using 2,2-diphenyl-1-picrylhydrazyl and 2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) assays. The expression of MMP-1 was tested by western blotting and ELISA kits. QAF effects on phosphorylation of the MAPK (p38, JNK, and ERK) pathway and transcription factor AP-1, which enhances the expression of MMPs, were analyzed by western blots. Results We identified two major active components in QAF water extracts, gallotannic acid and ellagic acid. The QAF aqueous extracts recovered UVB-induced cell toxicity and reduced oxidative stress by inhibiting intracellular ROS generation in HaCaT cells. QAF rescued UVB-induced collagen degradation by suppressing MMP-1 expression. The anti-photoaging activities of QAF were associated with the inhibition of UVB-induced phosphorylation of extracellular signal-regulated kinase (ERK) and activator protein 1 (AP-1). Our findings indicated that QAF prevents UVB-induced skin damage due to collagen degradation and MMP-1 activation via inactivation of the ERK/AP-1 signaling pathway. Overall, this study strongly suggests that QAF exerts anti-skin-aging effects and is a potential natural biomaterial that inhibits UVB-induced photoaging. Conclusion These results show that QAF water extract effectively prevents skin photoaging by enhancing collagen deposition and inhibiting MMP-1 via the ERK/AP-1 signaling pathway.

This study aims to screen and identify the multi-mechanism antistress effects of an extract of Hippophae rhamnoides L. (HR) leaves on corticosterone (CORT)-induced injury, N-methyl-d-aspartate (NMDA) receptor and serotonin 6 (5-hydroxytryptamine 6, 5-HT6) receptor activity tests (in vitro), electric foot shock and forced swimming tests (FSTs) (in vivo), and tests for hippocampal CORT and monoamine levels (ex vivo), in search of active principles and underlying mechanisms of action. We confirmed that the water extract of HR (HRW) and various ethanol extracts of HR confer protective effects against CORT-induced impairments in SH-SY5Y cells and antagonistic effects on NMDA receptors and the 5-HT6 receptor by using primary cultured rat hippocampal neurons and a stable 5-HT6 receptor-expressing cell line, respectively. In addition, we confirmed the antistress effects of HRW in an electric foot shock stress model in mice and explored the underlying mechanisms of its action. We observed that HRW treatmen...

In this study, we investigated the relationship between anti-inflammatory mechanisms and the combined ameliorating effects of rose hip powder (RHP) and green tea seed extract (GTSE) in a monosodium iodoacetate (MIA)-induced osteoarthritis (OA) animal model. We confirmed the individual effects of RHP (500 mg/kg bw) and GTSE (50 mg/kg bw) in the OA model. Treatment with the mixture of RHP and GTSE (Mix) resulted in significantly enhanced stance and propulsion times compared to treatment with RHP or GTSE alone. To examine the combined effects of RHP and GTSE in vivo, pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were measured. The administration of Mix significantly reduced the expression of pro-inflammatory cytokines. Additionally, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions were attenuated to a greater extent after the administration of Mix compared to the other treatments. Furthermore, we evaluated the anti-osteoarthritic ...