Antidepressant effects of p-coumaric acid isolated from Vaccinium bracteatum leaves extract on chronic restraint stress mouse model and antagonism of serotonin 6 receptor in vitro.

BACKGROUND: Vaccinium bracteatum Thunb. leaves (VBL) are used in traditional herbal medicines to treat various biological diseases. p-coumaric acid (CA), the main active component of VBL, has neuroprotective effects against corticosterone-induced damage in vitro. However, the effects of CA on immobility induced by chronic restraint stress (CRS) in a mouse model and 5-HT receptor activity have not been investigated. HYPOTHESIS/PURPOSE: We investigated the antagonistic effects of VBL, NET-D1602, and the three components of Gαs protein-coupled 5-HT receptors. Additionally, we identified the effects and mechanism of action of CA, the active component of NET-D1602, in the CRS-exposed model. METHODS: For in vitro analyses, we used 1321N1 cells stably expressing human 5-HT6 receptors and CHO-K1 expressing human 5-HT4 or 5-HT7 receptors cell lines to study the mechanism of action. For in vivo analyses, CRS-exposed mice were orally administered CA (10, 50, or 100 mg/kg) daily for 21 consecutive days. The effects of CA were analyzed by assessing behavioral changes using a forced swim test (FST), measuring levels of hypothalamic-pituitary-adrenal (HPA) axis-related hormones in ntial therapeutic effects as 5-HT6 receptor antagonists for neurodegenerative diseases and depressioserum, and acetylcholinesterase (AChE), monoamines, including 5-HT, dopamine, and norepinephrine, using enzyme-linked immunosorbent assay kits. The underlying molecular mechanisms of the serotonin transporter (SERT), monoamine oxidase A (MAO-A), and extracellular signal-regulated kinase (ERK)/protein kinase B (Akt)/mTORC1 signaling were detected using western blotting. RESULTS: CA was confirmed to be an active component in the antagonistic effects of NET-D1602 on 5-HT6 receptor activity through decreases in cAMP and ERK1/2 phosphorylation. Moreover, CRS-exposed mice treated with CA showed a significantly reduced immobility time in the FST. CA also significantly decreased corticosterone, corticotropin-releasing hormone (CRH), and adrenocorticotropic hormone (ACTH) levels. CA enhanced 5-HT, dopamine, and norepinephrine levels in the hippocampus (HC) and prefrontal cortex (PFC) but decreased MAO-A and SERT protein levels. Similarly, CA significantly upregulated the ERK, Ca2+/calmodulin-dependent protein kinase II (CaMKII), Akt/mTOR/p70S6K/S6 signaling pathways in both HC and the PFC. CONCLUSION: CA contained in NET-D1602 may play the antidepressant effects against CRS-induced depression-like mechanism and the selective antagonist effect of 5-HT6 receptor.

Protective effects of Quercus acuta Thunb. fruit extract against UVB-induced photoaging through ERK/AP-1 signaling modulation in human keratinocytes.

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.

The complete chloroplast genome of Artemisia Montana (Nakai) Pamp. (Asteraceae), a traditional medicinal herb in Korea.

Artemisia Montana (Nakai) Pamp. is a widely used heath food and a well-known traditional Korean herbal medicine. The complete chloroplast genome sequence of A. Montana was determined using high-throughput sequencing technology. Chloroplast genome was 151,133 bp in length, with a large single-copy (LSC) region of 98,497 bp, a small single-copy (SSC) region of 18,352 bp, separated by two inverted repeat (IR) regions of 17,142 bp each. It contained a total of 113 genes, with an overall GC content of 37.5%. The phylogenetic analysis showed that A. montana most closely related to A. feddei. This result will enrich the genetic resources of medicinal plant and useful for future investigation of genetics, evolution and identification of Artemisia species.

Vaccinium bracteatum Improves Spatial Learning and Memory by Regulating N-methyl-D-aspartate Receptors and Tau Phosphorylation in Chronic Restraint Stress-Induced Memory Impaired Mice.

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.

Laxative Activity of the Hot-Water Extract Mixture of Hovenia dulcis Thunb. and Phyllostachys pubescens Mazel in Chronic Constipation Model SD Rats.

This study examined the laxative effects of hot-water extracts of Hovenia dulcis Thunb. (HD), Phyllostachys pubescens Mazel (PM), and a 2:8 mixture of both (HP) in two chronic constipation models. For the loperamide-induced constipation model, animals were divided into an untreated group, negative control group (loperamide 4 mg/kg), positive control group (bisacodyl 4 mg/kg) group, and six treatment groups (HP 100 or 400, HD 50 or 100, and PM 100 or 400 mg/kg). For the lowfiber diet-induced constipation model, animals were divided into an untreated group (normal diet), negative control group (low-fiber diet), positive control group (Agio granule, 620 mg/kg), and the same treatment groups. Fecal number, weight, fecal water content, and intestinal transit ratio were higher in the groups treated with HP, HD, and PM than in the groups treated with loperamide or lowfiber diet. Thickness of colon mucosa and muscle layers were increased in the treated groups. Colon tension increased in the HP groups, and [Ca2+]i measurements using fura-2 as an indicator showed that HP inhibits ATP-mediated Ca2+ influx in IEC-18 cells. These results showed that the HP mixture has laxative activity by increased mucin secretion and inducing contractile activity and relaxation. It may be a useful therapeutic strategy for ameliorating in chronic constipation.

Sedative and hypnotic effects of Vaccinium bracteatum Thunb. through the regulation of serotonegic and GABAA-ergic systems: Involvement of 5-HT1A receptor agonistic activity.

The present study was conducted to investigate the sedative and hypnotic activities of Vaccinium bracteatum Thunb. fruit (VBFW) in an animal model and to identify the underlying mechanisms of its action. VBFW exhibited sedative effects through a reduction in the locomotor activity in the open field test (OFT). In addition, VBFW significantly reduced the sleep latency and increased total sleep duration in pentobarbital-induced sleeping behaviors in mice. The effects of 4-Chloro-DL-phenylalanine methyl ester hydrochloride (PCPA) were studied in normal and serotonin-depleted mice. Additionally, the changes in the related serum corticosterone (CORT) and neurotransmitter levels were evaluated. Pretreatment with VBFW (50, and 100 mg/kg) produced a significant decrease in the immobility time in the forced swim test (FST), while VBFW 100 plus PCPA treatment attenuated the change in immobility time observed following administration of VBFW alone. However, VBFW plus PCPA treatments did not significantly influence the changes in the locomotor activity that were induced by VBFW alone. The results suggest that VBFW leads to a decrease in the levels of serum CORT and norepinephrine in the hippocampus (HC) region (P < 0.01). Furthermore, PCPA treatment alone decreased serotonin (5-HT) levels in the HC (P < 0.05) and the prefrontal cortex (PFC; P < 0.05), while VBFW plus PCPA significantly increased the 5-HT levels in both the HC and the PFC (P < 0.05). In addition, we also found that VBFW showed a strong agonistic effect at the 5-HT1A receptor by activating 5-HT1A receptor-mediated intracellular Ca2+ and ERK1/2 phosphorylation. Similarly, VBFW (30 and 100 µg/mL) significantly increased the intracellular Cl- influx through its effects on the γ-aminobutyric acid type A receptor (GABAA receptor) subunits (α5, ß1, and ß2) in primary rat cerebellar granule cells. Moreover, the glutamate decarboxylase (GAD)65/67 protein was upregulated following VBFW treatment (30 and 100 µg/mL). The results of our study indicate that VBFW induces sedative and hypnotic effects by regulating the serotonergic and GABAA-ergic systems, which is possibly associated with 5-HT1A receptor agonistic activity. Additionally, this data suggests that VBFW up-regulates intracellular Cl- and GABAA receptor subunits as well as GAD65/67 protein levels.

In vitro and in vivo androgen regulation of Dendropanax morbiferus leaf extract on late-onset hypogonadism.

Late-onset hypogonadism (LOH) is associated with advancing age and is caused by a deficiency in serum testosterone levels. The aim of this study was to examine the effect of a Dendropanax morbiferus H.Lév. leaf extract (DME) on LOH using TM3 cells and aging male rats as in vitro and in vivo models, respectively. The in vitro effects of DME on testosterone levels and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) protein expression in TM3 cells were analyzed. In the in vivo experiments, DME was orally administered to rats at three doses (50, 100, and 200 mg/kg/day) for 4 weeks. DME significantly increased the testosterone levels and 3ß-HSD protein expression in TM3 cells. The DME groups showed significantly increased levels of androgenic hormones such as testosterone and dehydroepiandrosterone sulfate. The sex hormone-binding globulin production was significantly lower in the DME groups than that in the control group, while the neurohormone levels in the hypothalamic-pituitary-gonadal axis markedly increased. No significant differences were observed in the glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, and prostate-specific antigen levels among the DME and control groups. The triglyceride and low-density lipoprotein cholesterol levels were significantly lower, while the high-density lipoprotein cholesterol levels were significantly higher in the DME groups than those in the control group. The latency time in the rotarod, treadmill, and swimming tests increased with the DME treatment. Furthermore, the sperm counts in the epididymis markedly increased. These results suggest that DME can be effectively used to alleviate the symptoms of LOH.

Vaccinium bracteatum Leaf Extract Reverses Chronic Restraint Stress-Induced Depression-Like Behavior in Mice: Regulation of Hypothalamic-Pituitary-Adrenal Axis, Serotonin Turnover Systems, and ERK/Akt Phosphorylation.

The leaves of Vaccinium bracteatum Thunb. are a source of traditional herbal medicines found in East Asia. The present study aimed to evaluate the mechanisms underlying the antidepressant-like effects of water extract of V. bracteatum Thunb. leaves (VBLW) in a mouse model of chronic restraint stress (CRS) and to identify the possible molecular in vitro mechanisms of the neuroprotective effects. The CRS-exposed mice were orally administered VBLW (100 and 200 mg/kg) daily for 21 days consecutively. The behavioral effects of VBLW were assessed through the forced swim test (FST) and the open field test (OFT). The levels of serum corticosterone (CORT), corticotropin releasing hormone (CRH), and adrenocorticotropin hormone (ACTH), brain monoamines, such as serotonin, dopamine, and norepinephrine, and serotonin turnover by tryptophan hydroxylase 2 (TPH2), serotonin reuptake (SERT), and monoamine oxidase A (MAO-A) were evaluated, in addition to the extracellular signal-regulated kinases (ERKs)/protein kinase B (Akt) signaling pathway. CRS-exposed mice treated with VBLW (100 and 200 mg/kg) showed significantly reduced immobility time and increased swimming and climbing times in the FST, and increased locomotor activity in the OFT. Moreover, CRS mice treated with VBLW exhibited significantly decreased CORT and ACTH, but enhanced brain monoamine neurotransmitters. In addition, CRS mice treated with VBLW had dramatically decreased protein levels of MAO-A and SERT, but increased TPH2 protein levels in the hippocampus and the PFC. Similarly, VBLW significantly upregulated the ERKs/Akt signaling pathway in the hippocampus and the PFC. Furthermore, VBLW showed neuroprotective effects via increased CREB phosphorylation in CORT-induced cell injury that were mediated through the ERK/Akt/mTOR signaling pathways. These results suggested that the antidepressant-like effects of VBLW might be mediated by the regulation of the HPA axis, glucocorticoids, and serotonin turnover, such as TPH2, SERT, and MAO-A, as well as the concentration of monoamine neurotransmitters, and the activities of ERK and Akt phosphorylation, which were possibly associated with neuroprotective effects.

Antidepressant-Like Effects of Vaccinium bracteatum in Chronic Restraint Stress Mice: Functional Actions and Mechanism Explorations.

The fruit of Vaccinium bracteatum Thunb. (VBF) is commonly known as the oriental blueberry in Korea. The aim of this study was to evaluate the antidepressant-like effects of water VBF extract (VBFW) in a mouse model of chronic restraint stress (CRS) and to identify the underlying mechanisms of its action. The behavioral effects of VBFW were assessed in the forced swim test (FST) and open field test (OFT). The levels of serum corticosterone (CORT), brain monoamines, in addition to the extracellular signal-regulated kinases (ERKs)/protein kinase B (Akt) signaling pathway were evaluated. VBFW treatment significantly reduced the immobility time and increased swimming time in FST without altering the locomotor activity in unstressed mice. Furthermore, CRS mice treated with VBFW exhibited a significantly decreased immobility time in FST and serum CORT, increased locomotor activity in OFT, and enhanced brain monoamine neurotransmitters. Similarly, VBFW significantly upregulated the ERKs/Akt signaling pathway in the hippocampus and PFC. In addition, VBFW may reverse CORT-induced cell death by enhancing cyclic AMP-responsive element-binding protein expression through the up-regulation of ERKs/Akt signaling pathways. In addition, VBFW showed the strong antagonistic effect of the 5-HT[Formula: see text] receptor by inhibiting 5-HT-induced intracellular Ca[Formula: see text] and ERK1/2 phosphorylation. Our study provides evidence that antidepressant-like effects of VBFW might be mediated by the regulation of monoaminergic systems and glucocorticoids, which is possibly associated with neuroprotective effects and antagonism of 5-HT[Formula: see text] receptor.

Estrogen Receptor α Regulates Dlx3-Mediated Osteoblast Differentiation.

Estrogen receptor α (ER-α), which is involved in bone metabolism and breast cancer, has been shown to have transcriptional targets. Dlx3 is essential for the skeletal development and plays an important role in osteoblast differentiation. Various osteogenic stimulators and transcription factors can induce the protein expression of Dlx3. However, the regulatory function of ER-α in the Dlx3 mediated osteogenic process remains unknown. Therefore, we investigated the regulation of Dlx3 and found that ER-α is a positive regulator of Dlx3 transcription in BMP2-induced osteoblast differentiation. We also found that ER-α interacts with Dlx3 and increases its transcriptional activity and DNA binding affinity. Furthermore, we demonstrated that the regulation of Dlx3 activity by ER-α is independent of the ligand (estradiol) binding domain. These results indicate that Dlx3 is a novel target of ER-α, and that ER-α regulates the osteoblast differentiation through modulation of Dlx3 expression and/or interaction with Dlx3.

The laxative effects of Maesil (Prunus mume Siebold & Zucc.) on constipation induced by a low-fibre diet in a rat model.

Maesil (the fruit of Prunus mume Siebold & Zucc.) has long been used as an alternative medicine and functional food in Korea and Japan for preventive and therapeutic purposes. We examined the laxative effect of unripe Maesil (UM) and ripe Maesil (RM) in a rat model on constipation induced by a low-fibre diet and the possible mechanisms of Maesil in the rat colon. In vivo studies were conducted on the low-fibre diet-induced constipation rat model, and isolated rat colon was used in in vitro experiments to measure the changes in spontaneous colon contraction generated by Maesil and organic acids as standard and effectual ingredients, respectively. The aqueous extract of both UM and RM applied orally (100 and 300 mg/kg) produced significant increase of faeces frequency (p < 0.05) and moisture (p < 0.001). Moreover, the number faecal pellets number was reduced (p < 0.05) in the distal colons of the Maesil-treated rats. Gastrointestinal (GI) motility, measured by charcoal meal, was activated more fully by UM than in the low-fibre diet group. Both UM and RM and its organic acids produced a dose-dependent stimulation of the spontaneous contractile amplitude (p < 0.001) and frequency (p < 0.01) of the isolated rat colon. Although both UM and RM were an effective laxative, the RM was significantly more effective than the UM in the in vivo and in vitro constipation experiments because of the changes in the composition of organic acids during the ripening of the fruit. Our results demonstrated that Maesil was effective in promoting the frequency of defaecation and contraction of the rat colon, which provided scientific basis to support the use of Maesil as potential therapeutics in treating constipation.

The flavonoids apigenin and luteolin suppress ultraviolet A-induced matrix metalloproteinase-1 expression via MAPKs and AP-1-dependent signaling in HaCaT cells.

BACKGROUND: Ultraviolet (UV) irradiation causes major changes in skin connective tissues as a result of the degradation of collagen, a major structural component of the extracellular matrix. This process is likely mediated by matrix metalloproteinases (MMPs). Such changes in collagenous skin tissues have been suggested to be causes of cutaneous aging and skin cancer. OBJECTIVE: We investigated the protective effects of apigenin and luteolin on immortalized human keratinocytes (HaCaT) against UVA damage. We then explored the inhibitory effects of apigenin and luteolin on UVA-induced MMP-1 and investigated the molecular mechanism underlying those effects. METHODS: HaCaT cells were treated with apigenin and luteolin for the indicated times followed by irradiation with UVA. Those effects were assessed by semi-quantitative PCR, Western blotting and enzymic activity assays. RESULTS: These two compounds, at concentrations of 1-5µM, increased the viability of, and inhibited ROS production in HaCaT cells exposed to UVA irradiation. Pre-treatment of HaCaT cells with apigenin and luteolin also inhibited UVA-induced production of the collagenases MMP-1. They also suppressed UVA-induced expression of c-Jun and c-Fos and the phosphorylation of three MAP kinases, upstream modulators of AP-1. Furthermore, the same two flavonoids decreased the UVA-induced influx of Ca(2+) into HaCaT cells and the phosphorylation of Ca(2+)/calmodulin-dependent kinases (CaMKs). CONCLUSION: The results indicate that apigenin and luteolin inhibited UVA-induced collagenolytic MMP-1 production by interfering with Ca(2+)-dependent MAPKs and AP-1 signaling. They may thus be potentially useful in the prevention and treatment of skin photoaging.

Bisphenol A-induced aromatase activation is mediated by cyclooxygenase-2 up-regulation in rat testicular Leydig cells.

Bisphenol A (4,4'-dihydroxy-2,2-diphenylpropane; BPA) is an endocrine disruptor that affects the reproductive health of wildlife and possibly of humans. Evidence suggests that BPA interrupts ovarian steroidogenesis by altering steroidogenic enzymes. We evaluated the effect of BPA on aromatase expression in rat testicular Leydig cells. In addition, we investigated whether cyclooxygenase-2 (COX-2) was involved in BPA-induced aromatase expression. BPA induced a time- and concentration-dependent increase in aromatase protein expression in rat testicular Leydig R2C cells. It also increased aromatase gene expression and its enzyme and promoter activity, but reduced testosterone synthesis; increased COX-2 mRNA expression and promoter activity, the production of prostaglandin E(2) (PGE(2)), and the gene expression of PGE(2) (EP2 and EP4) receptors; induced the activation of cyclic adenosine monophosphate (cAMP) response element (CRE) and CREB binding; and increased the phosphorylation of protein kinase A (PKA), Akt, and mitogen-activated protein (MAP) kinase signaling pathways. BPA activation of aromatase was reversed by various inhibitors (COX-2, PKA, Akt, ERK, JNK, and p38). Taken together, these results suggest that BPA increases aromatase activity, which is correlated with COX-2 up-regulation mediated by the CRE, PKA, Akt, and MAP kinase signaling pathways in rat testicular Leydig cells.

Methoxychlor-induced inducible nitric oxide synthase and proinflammatory cytokines expression in macrophages via NF-kappaB, ERK, and p38 mitogen-activated protein kinases.

Methoxychlor (MXC) is a pesticide that was developed as a replacement for dichlorodiphenyltrichloroethane. The influence of MXC on cytokine production or the functions of macrophages is unclear. This study examined the effects of MXC on the production of nitric oxide (NO) and the proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha), and analyzed the molecular mechanism in mouse macrophages. The addition of MXC to macrophages induced the production of NO and proinflammatory cytokines and expression levels of these genes in a dose-dependent manner. The NF-kappaB sites were identified in the promoter of the iNOS and proinflammatory cytokines genes. The transient expression and electrophoretic mobility shift assays revealed that the NF-kappaB transcription factor mediated the MXC-induced increase in the iNOS and proinflammatory cytokines expression levels. In addition, MXC induced the rapid phosphorylation of the ERK1/2 and p38 MAPK. This demonstrates that MXC stimulates the production of NO and proinflammatory cytokines and can up-regulate the expression levels of these genes via NF-kappaB transactivation and ERK1/2 and p38 MAPK phosphorylation. Overall, this study provides evidence showing that MXC has inflammatory potential that is previously unrecognized immunomodulating activity.