Influence of Supplementation of Ecklonia cava Polyphenols on Learning, Memory, and Brain Fatty Acid Composition in Mice.

AIMS: The objective of this study was to determine the effects of intake of polyphenols from Ecklonia cava on spatial task performance and nervous fatty acid composition in mice fed with a high-fat diet. MATERIALS AND METHODS: Thirty mice were randomly divided into three groups; each group consisted of ten mice. The control group was fed 5% soybean oil as a fat source, whereas the high fat (HF) group was fed a 15% lard diet and the polyphenol (ECP) group was maintained on the HF diet plus 1% E. cava polyphenols. RESULTS: The ECP group exhibited a short escape latency and better memory retention in the Morris water maze test compared with the control and HF groups (P<0.05). In addition, the ECP group showed a greater increase in avoidance latency than that of the HF group (P<0.05). Moreover, the consumption of polyphenols from E. cava presented higher levels of DHA in the brain and retina (P<0.05). CONCLUSION: This study suggested the positive effects of polyphenols from E. cava on memory retention, which might be partially attributed to the increased levels of DHA in the brain.

Oleracone C from Portulaca oleracea attenuates UVB-induced changes in matrix metalloproteinase and type I procollagen production via MAPK and TGF-ß/Smad pathways in human keratinocytes.

BACKGROUND: Chronic exposure to ultraviolet (UV) radiation induces photo-oxidation, which in turn causes the overproduction of matrix metalloproteinases (MMPs) and collagen degradation. These symptoms are referred to as photoaging, which is characterized by skin thickness, irregular pigmentation, elastosis and coarse wrinkles. In this study, the protective effects of oleracone C isolated from Portulaca olerace against UVB-induced changes in MMPs and type I procollagen production were investigated in human keratinocytes. METHODS: Human immortalized keratinocytes have been used as an in vitro cell model to study the abnormal skin barrier development such as in photoaging. The effects of the compound on cell viability were determined by colorimetric MTT assay. This study also measured ROS production using DCFH-DA assay. Releases of MMPs and type Iα1 procollagen were analysed by ELISA. RT-PCR and Western blot were carried out to test the expressions of mRNA and proteins related to MMPs and type I procollagen biosynthesis. RESULT: Effect of oleracone C against UVB-mediated oxidative stress was evaluated measuring its ability to eliminate UVB-induced activation of reactive oxygen species (ROS). Treatment of oleracone C hindered the production of intracellular ROS. UVB exposure increased MMPs (MMP-1, MMP-2 and MMP-9) release from keratinocytes and decreased the release of type I procollagen. Treatment with oleracone C reversed these effects of UVB exposure. Oleracone C treatment also diminished the intracellular expression of MMP-1, MMP-2 and MMP-9 and elevated the type I procollagen. Oleracone C suppressed the UVB irradiation-dependent upregulation phosphorylation of p38 and ERK1/2 in the mitogen-activated protein kinase (MAPK) pathway. Furthermore, oleracone C stimulated collagen production through the TGF-ß signalling pathway, which activates collagen synthesis in UVB-irradiated keratinocytes. CONCLUSION: These findings reasonably suggest ameliorating the potential of oleracone C against the UVB-induced photoaging of the human keratinocytes.

RÉSUMÉ: CONTEXTE: L'exposition chronique aux rayons ultraviolets (UV) induit la photo-oxydation, qui à son tour entraîne la surproduction de métalloprotéases matricielles (MMP) et la dégradation du collagène. Ces symptômes sont appelés photovieillissement, qui se caractérise par une épaisseur de la peau, une pigmentation irrégulière, une élastose et des rides grossières. Dans cette étude, les effets protecteurs de l'oléracone C isolée à partir du pourpier potager contre les changements induits par les UVB dans les MMP et la production de procollagène de type I ont été étudiés dans les kératinocytes humains. MÉTHODES: Les kératinocytes humains immortalisés ont été utilisés comme modèle cellulaire in vitro pour étudier le développement anormal de la barrière cutanée, comme c'est le cas dans le photovieillissement. Les effets du composé sur la viabilité cellulaire ont été déterminés par test colorimétrique au MTT. Cette étude a également mesuré la production de DRO à l'aide du dosage DCFH-DA. Les productions de MMP et de procollagène de type Iα1 ont été analysées par la méthode ELISA. La RT-PCR et le Western blot ont été réalisés pour tester les expressions de l'ARNm, et des protéines liées aux MMP et à la biosynthèse du procollagène de type I. RÉSULTAT: L'effet de l'oléracone C contre le stress oxydatif médié par les UVB a été évalué en mesurant sa capacité à éliminer l'activation induite par les UVB des dérivés réactifs de l'oxygène (DRO). Le traitement par oléracone C a empêché la production de DRO intracellulaires. L'exposition aux UVB a augmenté la production de MMP (MMP-1, MMP-2 et MMP-9) par les kératinocytes et a diminué la production de procollagène de type I. Le traitement par oléracone C a inversé ces effets de l'exposition aux UVB. Le traitement par oléracone C a également diminué l'expression intracellulaire de MMP-1, MMP-2 et MMP-9, et a augmenté le taux de procollagène de type I. L'oléracone C a supprimé la phosphorylation de régulation à la hausse dépendante de l'exposition aux UVB de p38 et ERK1/2 dans la voie de la protéine kinase activée par des agents mitogènes (Mitogen-Activated Protein Kinase, MAPK). En outre, l'oléracone C a stimulé la production de collagène par la voie de signalisation de TGF-ß, qui active la synthèse du collagène dans les kératinocytes exposés aux UVB. CONCLUSION: Ces résultats indiquent raisonnablement une amélioration du potentiel de l'oléracone C contre le photovieillissement induit par les UVB des kératinocytes humains.

Inhibitory Effects of Sesquiterpenoids Isolated from Artemisia scoparia on Adipogenic Differentiation of 3T3-L1 Preadipocytes.

Obesity and related complications are significant health issues in modern society, largely attributed to a sedentary lifestyle and a carbohydrate-rich diet. Since anti-obesity drugs often come with severe side effects, preventative measures are being sought globally, including dietary changes and functional foods that can counteract weight gain. In this context, plant-based metabolites are extensively studied for their advantageous biological effects against obesity. Several plants within the Artemisia genus have been reported to possess anti-adipogenic properties, preventing adipocytes from maturing and accumulating lipids. The present study investigated the anti-adipogenic potential of two sesquiterpenoids, reynosin and santamarine, isolated from A. scoparia in adipose-induced 3T3-L1 preadipocytes. Differentiating 3T3-L1 adipocytes treated with these isolated compounds displayed fewer adipogenic characteristics compared to untreated mature adipocytes. The results indicated that cells treated with reynosin and santamarine accumulated 55.0% and 52.5% fewer intracellular lipids compared to untreated control adipocytes, respectively. Additionally, the mRNA expression of the key adipogenic marker, transcription factor PPARγ, was suppressed by 87.2% and 91.7% following 60 µM reynosin and santamarine treatment, respectively, in differentiated adipocytes. Protein expression was also suppressed in a similar manner, at 92.7% and 82.5% by 60 µM reynosin and santamarine treatment, respectively. Likewise, SERBP1c and C/EBPα were also downregulated at both gene and protein levels in adipocytes treated with samples during differentiation. Further analysis suggested that the anti-adipogenic effect of the compounds might be a result of AMPK activation and the subsequent suppression of MAPK phosphorylation. Overall, the present study suggested that sesquiterpenoids, reynosin, and santamarine were two potential bioactive compounds with anti-adipogenic properties. Further research is needed to explore other bioactive agents within A. scoparia and elucidate the in vivo action mechanisms of reynosin and santamarine.

Ligustrum japonicum Thunb. Fruits Exert Antiosteoporotic Properties in Bone Marrow-Derived Mesenchymal Stromal Cells via Regulation of Adipocyte and Osteoblast Differentiation.

Ligustrum japonicum fruits have been used as a part of traditional medicinal practices and supplements in Korea and Japan. It has been reported to possess various bioactivities, but its antiosteoporotic potential and active substances have not been reported yet. The present study followed an ALP activity and lipid accumulation-guided screening of L. japonicum fruits for antiosteoporotic compounds and isolated salidroside as an active compound. Antiosteoporotic effects of L. japonicum fruits and salidroside were examined in mesenchymal stromal cells by their ability to enhance osteoblast formation by increased ALP activity and osteogenic marker gene expression while suppressing adipogenesis by inhibition of lipid accumulation and adipocyte marker gene expressions. Results showed that salidroside was able to enhance osteoblast differentiation via Wnt/BMP signaling pathway overactivation and suppress the PPARγ-mediated adipocyte differentiation, both through the MAPK pathway. In conclusion, L. japonicum fruits were suggested to possess antiosteoporotic activities and to be a source of antiosteoporotic substances such as salidroside.

Effect and Comparison of Luteolin and Its Derivative Sodium Luteolin-4'-sulfonate on Adipogenic Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells through AMPK-Mediated PPARγ Signaling.

Luteolin is a common phytochemical from the flavonoid family with a flavone structure. Studies reported several bioactivities for luteolin and similar flavones. Attenuating the increased adipogenesis of bone marrow cells (hBM-MSCs) has been regarded as a therapeutic target against osteoporotic bone disorders. In the present study, the potential roles of luteolin and its sulfonic acid derivative luteolin-OSO3Na in regulating adipogenic differentiation of hBM-MSCs were investigated. Adipo-induced cells were treated with or without compounds, and their effect on adipogenesis was evaluated by adipogenic marker levels such as lipid accumulation and PPARγ pathway activation. Luteolin hindered the adipogenic lipid accumulation in adipo-induced hBM-MSCs. Immunoblotting and reverse transcription-polymerase chain reaction analysis results indicated that luteolin downregulated PPARγ and downstream factors of C/EBPα and SREBP1c expression which resulted in inhibition of adipogenesis. Luteolin-OSO3Na showed similar effects; however, it was significantly less effective compared to luteolin. Investigating p38, JNK, and ERK MAPKs and AMPK activation indicated that luteolin suppressed the MAPK phosphorylation while stimulating AMPK phosphorylation. On the other hand, luteolin-OSO3Na was not able to notably affect the MAPK and AMPK activation. In conclusion, this study suggested that luteolin inhibited adipogenic differentiation of hBM-MSCs via upregulating AMPK activation. Replacing its 4'-hydroxyl group with sulfonic acid sodium salt diminished its antiadipogenic effect indicating its role in regulating AMPK activation. The general significance is that luteolin is a common phytochemical with various health-beneficial effects. The current study suggested that luteolin may serve as a lead compound for developing antiosteoporotic substances with antiadipogenic properties.

3,5-dicaffeoyl­epi-quinic acid from Atriplex gmelinii enhances the osteoblast differentiation of bone marrow-derived human mesenchymal stromal cells via WnT/BMP signaling and suppresses adipocyte differentiation via AMPK activation.

BACKGROUND: Impaired bone formation is one of the reasons behind osteoporosis. Alterations in the patterns of mesenchymal stromal cell differentiation towards adipocytes instead of osteoblasts contribute to osteoporosis progression. Natural anti-osteoporotic agents are effective and safe alternatives for osteoporosis treatment. PURPOSE: In this context, 3,5-dicaffeoyl­epi-quinic acid (DCEQA) which is a derivative of chlorogenic acid with reported bioactivities was studied for its osteogenic differentiation enhancing potential in vitro. METHODS: Anti-osteoporotic effects of DCEQA were investigated in human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) which were induced to differentiate into osteoblasts or adipocytes with or without DCEQA treatment. Changes in the osteogenic and adipogenic markers such as ALP activity and lipid accumulation, respectively, were observed along with differentiation-specific activation of mitogen activated protein kinase (MAPK) pathways. RESULTS: At 10 µM concentration, DCEQA increased the proliferation of bone marrow-derived human mesenchymal stromal cells (hBM-MSCs) during osteoblast differentiation. The expression of osteogenic markers ALP, osteocalcin, Runx2, BMP2 and Wnt 10a was upregulated by DCEQA treatment. The ALP activity and extracellular mineralization were also increased. DCEQA elevated the phosphorylation levels of p38 and JNK MAPKs as well as the activation of ß-catenin and Smad1/5. DCEQA suppressed the lipid accumulation and downregulated expression of adipogenic markers PPARγ, C/EBPα and SREBP1c in adipo-induced hBM-MSCs. DCEQA also decreased the phosphorylation of p38 and ERK MAPKs and stimulated the activation of AMPK in hBM-MSC adipocytes. CONCLUSION: DCEQA was suggested to enhance osteoblast differentiation via stimulating Wnt/BMP signaling. The adipocyte differentiation inhibitory effect of DCEQA was suggested to arise from its ability to increase AMPK phosphorylation. Overall, DCEQA was shown to possess osteogenesis enhancing and adipogenesis inhibitory properties which might facilitate its use against osteoporotic conditions.

Antiphotoaging Effects of 3,5-Dicaffeoyl-epi-quinic Acid via Inhibition of Matrix Metalloproteinases in UVB-Irradiated Human Keratinocytes.

UVB exposure is one of the causes of several skin complications including but not limited to premature aging, wrinkle formation, and hyperpigmentation. UV-induced skin aging is called photoaging, and oxidative stress-induced overexpression of matrix metalloproteinases (MMPs) is the main reason behind the photoaging-mediated collagen degradation. Natural origin inhibitors of MMPs are regarded as a promising approach to prevent or treat photoaging. Therefore, the present study investigated the protective effects of 3,5-dicaffeoyl-epi-quinic acid (DCEQA) in human HaCaT keratinocytes against UVB irradiation-related dysregulation of MMPs. Changes in the mRNA and protein expression and release of MMP-1, -2, and -9 were observed after UVB irradiation with or without DCEQA treatment. In addition, the effect of DCEQA on the activation of p38, JNK, and ERK MAPKs was analyzed. Treatment of UVB-irradiated HaCaT cells with 10 µM DCEQA significantly suppressed the overexpression of both mRNA and protein of MMP-1, -2, and -9 while slightly increasing the diminished type I procollagen production. UVB-induced activation of MAPKs was also ameliorated by DCEQA treatment in a dose-dependent manner. Results indicated that DCEQA treatment was able to protect keratinocytes from UVB-induced photoaging by inhibiting the stimulated production of MMPs and the related decrease in collagen production. It was suggested that DCEQA downregulated the collagen degradation via inhibition of MAPK activation, which resulted in decreased MMP activity.

6-Acetyl-2,2-Dimethylchroman-4-One Isolated from Artemisia princeps Suppresses Adipogenic Differentiation of Human Bone Marrow-Derived Mesenchymal Stromal Cells via Activation of AMPK.

Obesity is a world-wide health concern with increasing mortality and morbidity rates. Development of novel therapeutic agents for obesity from phytochemicals may lead to the effective prevention and control of obesity and obesity-related complications. 6-acetyl-2,2-dimethylchroman-4-one (1) was isolated from a dietary plant, Artemisia princeps. The antiobesity effect of compound 1 was determined in human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) induced to differentiate into adipocytes. Treatment with compound 1 resulted in decreased lipid accumulation and expression of key adipogenic markers, proliferator-activated receptor-γ, CCAAT/enhancer-binding protein-α, and sterol regulatory element-binding transcription factor 1. It was also shown that compound 1 downregulated the adipogenesis-induced p38 and JNK MAPK activation, while upregulating adipogenesis inhibitory ß-catenin-dependent Wnt10b pathway. Compound 1 was also able to stimulate adenosine monophosphate-activated protein kinase phosphorylation, which was suggested to be the underlying mechanism that resulted in inhibition of adipogenesis in hBM-MSCs. In conclusion, 6-acetyl-2,2-dimethylchroman-4-one was identified as a bioactive constituent of A. princeps that exerts antiobesity properties via suppressing adipocyte formation.

3,5-Dicaffeoyl-epi-quinic acid inhibits the PMA-stimulated activation and expression of MMP-9 but not MMP-2 via downregulation of MAPK pathway.

Matrix metalloproteinases (MMPs), especially MMP-2 and MMP-9, are very important gelatinases that are overexpressed during tumor metastasis. Up to date, several MMP inhibitors have been developed from natural sources as well as organic synthesis. In the present study, the MMP-2 and MMP-9 inhibitory effects of 3,5-dicaffeoyl-epi-quinic acid (DCEQA), a caffeoylquinic acid derivative isolated from Atriplex gmelinii, were investigated in phorbol 12-myristate 13-acetate (PMA)-treated human HT1080 fibrosarcoma cells. Gelatin zymography and immunoblotting showed that DCEQA significantly inhibited the PMA-induced activation and expression of MMP-9 but was not able to show any effect against MMP-2. DCEQA treatment was also shown to upregulate the protein expression of tissue inhibitor of MMP-1 along with decreased MMP-9 protein levels. Moreover, the effect of DCEQA on phosphorylation of mitogen activated protein kinases (MAPKs), analyzed by immunoblotting, indicated the DCEQA inhibited the MMP-9 by downregulation of MAPK pathway. Collectively, current results suggested that DCEQA is a potent MMP-9 inhibitor and can be utilized as lead compound for treatment of pathological complications involving enhanced MMP activity such as cancer metastasis.

Anticatabolic and Anti-Inflammatory Effects of Myricetin 3-O-ß-d-Galactopyranoside in UVA-Irradiated Dermal Cells via Repression of MAPK/AP-1 and Activation of TGFß/Smad.

UV irradiation is one of the main causes of extrinsic skin aging. UV-mediated skin aging, also known as photoaging, causes excessive breakdown of extracellular matrix which leads skin to lose its elasticity and strength. Several phytochemicals are known to exert anti-photoaging effects via different mechanisms, partly due to their antioxidant properties. The current study has been carried out to determine the potential anti-photoaging properties of myricetin 3-O-ß-d-galacto-pyranoside (M3G), a flavonol glycoside isolated from L. tetragonum, in UVA-irradiated in vitro models; HaCaT keratinocytes and human dermal fibroblasts (HDFs). UVA-induced changes in MMP-1 and collagen production have been observed in HaCaT keratinocytes and HDFs. Further, UVA-induced activation of MAPK signaling, and pro-inflammatory cytokine production have been investigated. TGFß/Smad pathway has also been analyzed in UVA-irradiated HDFs. Treatment with M3G reversed the UVA-induced changes in MMP-1 and collagen production both in HaCaT keratinocytes and HDFs. UVA-mediated activation of p38, ERK and JNK MAPK activation was also inhibited by M3G treatment in HaCaT keratinocytes. In HDFs, M3G was able to upregulate the TGFß/Smad pathway activation. In addition, M3G downregulated the UVA-induced pro-inflammatory cytokines in keratinocytes and HDFs. It has been suggested that the M3G has exerted potential antiphotoaging properties in vitro, by attenuating UVA-induced changes in MMP-1 and collagen production in keratinocytes and dermal fibroblasts.

Artemisia princeps Inhibits Adipogenic Differentiation of 3T3-L1 Pre-Adipocytes via Downregulation of PPARγ and MAPK Pathways.

Artemisia princeps, the Korean mugwort, is an edible plant that has various beneficial effects on health, and which has been used as a part of traditional folk medicine. The current study investigated the possible effects of solvent (H2O, n-BuOH, 85% aq. MeOH, and n-hexane) partitioned fractions of A. princeps crude extract (APE) on adipogenic differentiation of 3T3-L1 mouse pre-adipocytes. Characteristics of the differentiated adipocytes were evaluated by Oil red O staining of intracellular lipid droplets, analyzing mRNA and protein levels of peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer-binding protein (C/EBP) α, and sterol regulatory element-binding protein (SREBP)-1c, and immunoblotting of phosphorylated mitogen-activated protein kinase (MAPK) pathway proteins such as p38, extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Introduction of APE fractions to differentiating adipocytes resulted in lowered lipid accumulation and downregulation of the PPARγ pathway. APE fractions significantly decreased mRNA and protein expression of PPARγ, C/EBPα, and SREBP-1c. Analysis of MAPK pathway activation showed similar results since treatment with the APE fraction treatment decreased levels of phosphorylated p38, ERK, and JNK. Overall, the n-BuOH and n-hexane fractions were observed to be the most active fractions to suppress adipogenesis-related signaling in 3T3-L1 cells. The promising ability of APE fractions to inhibit adipocyte differentiation of 3T3-L1 cells suggest that A. princeps has potential to be utilized as a source of anti-obesity compounds.

Phlorofucofuroeckol A from Edible Brown Alga Ecklonia Cava Enhances Osteoblastogenesis in Bone Marrow-Derived Human Mesenchymal Stem Cells.

The deterioration of bone formation is a leading cause of age-related bone disorders. Lack of bone formation is induced by decreased osteoblastogenesis. In this study, osteoblastogenesis promoting effects of algal phlorotannin, phlorofucofuroeckol A (PFF-A), were evaluated. PFF-A was isolated from brown alga Ecklonia cava. The ability of PFF-A to enhance osteoblast differentiation was observed in murine pre-osteoblast cell line MC3T3-E1 and human bone marrow-derived mesenchymal stem cells (huBM-MSCs). Proliferation and alkaline phosphatase (ALP) activity of osteoblasts during differentiation was assayed following PFF-A treatment along extracellular mineralization. In addition, effect of PFF-A on osteoblast maturation pathways such as Runx2 and Smads was analyzed. Treatment of PFF-A was able to enhance the proliferation of differentiating osteoblasts. Also, ALP activity was observed to be increased. Osteoblasts showed increased extracellular mineralization, observed by Alizarin Red staining, following PFF-A treatment. In addition, expression levels of critical proteins in osteoblastogenesis such as ALP, bone morphogenetic protein-2 (BMP-2), osteocalcin and ß-catenin were stimulated after the introduction of PFF-A. In conclusion, PFF-A was suggested to be a potential natural product with osteoblastogenesis enhancing effects which can be utilized against bone-remodeling imbalances and osteoporosis-related complications.

Evaluation of anti-adipogenic active homoisoflavonoids from Portulaca oleracea.

This study was performed to isolate antiobesity components from the crude extract of Portulaca oleracea. The crude extract was partitioned into n-hexane, 85% aqueous methanol, n-butanol, and water fractions. Their effects on adipogenic differentiation were evaluated in 3T3-L1 cells. Among the solvent fractions from P. olearacea, the 85% aq. MeOH effectively reduced the levels of lipid accumulation. Further purification of 85% aq. MeOH led to the isolation of the known homoisoflavonoids 1-4, as the active substances. The administration of homoisoflavonoids to adipocyte cells decreased the lipid accumulation and glucose consumption and increased the release of glycerol into culture medium. In particular, homoisoflavonoid 3 effectively down-regulated the adipogenic transcription genes such as peroxisome proliferator activated receptor-γ (PPARγ) and CCAAT/enhancer-binding proteins (C/EBPα), and adipogenic target genes such as fatty acid binding protein 4 (FABP4), fatty acid transport protein 1 (FATP1), and acyl-CoA synthase 1 (ACS1).

Protective effect of 3,5­dicaffeoyl­epi­quinic acid against UVB­induced photoaging in human HaCaT keratinocytes.

Derivatives of caffeoylquinic acid (CQA) have been studied and reported as potent bioactive molecules possessing various health benefits including antioxidant and anti­inflammatory activities. In the present study, the protective effect of 3,5­dicaffeoyl­epi­quinic acid (DCEQA) isolated from Atriplex gmelinii on UVB­induced damages was investigated in human HaCaT keratinocytes. The effect of DCEQA against UVB­induced oxidative stress­mediated damages was determined measuring its ability to alleviate UVB­induced elevation of oxidative stress, proinflammatory response and antioxidant enzyme suppression through nuclear factor­like 2 (Nrf2). Treatment with DCEQA hindered the generation of intracellular reactive oxygen species. Increased levels of proinflammatory cytokines TNF­α, COX­2, IL­6 and IL­1ß following UVB exposure were suppressed by the introduction of DCEQA. Additionally, DCEQA upregulated the mRNA and protein expression of antioxidant enzymes superoxide dismutase­1 and heme oxygenase­1 which were inhibited under UVB irradiation. Antioxidant enzyme regulation transcription factor Nrf2 was also upregulated in the presence of DCEQA. These results suggest that DCEQA prevents photoaging via protection of keratinocytes from UVB irradiation by ameliorating the oxidative stress and pro­inflammatory response.

3,5-Dicaffeoyl-Epi-Quinic Acid Isolated from Edible Halophyte Atriplex gmelinii Inhibits Adipogenesis via AMPK/MAPK Pathway in 3T3-L1 Adipocytes.

Atriplex gmelinii is an edible halophyte that has been suggested to possess various health benefits. In the present study, 3,5-dicaffeoyl-epi-quinic acid (DEQA) isolated from A. gmelinii was tested for its ability to prevent adipogenesis in 3T3-L1 cells. Also, the molecular mechanisms by which DEQA affects differentiation of 3T3-L1 cells were investigated. The introduction of DEQA to differentiating 3T3-L1 preadipocytes resulted in suppressed adipogenesis and lowered expression of adipogenesis-related factors, PPARγ, C/EBPα, and SREBP-1c. Treatment of 3T3-L1 adipocytes with DEQA notably decreased the levels of phosphorylated p38, ERK, and JNK. In addition, presence of DEQA upregulated the levels of both inactive and phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylase (ACC). Taken together, current results indicated that DEQA exhibited a significant antiadipogenesis activity by activation of AMPK and downregulation of MAPK signal pathways in 3T3-L1 preadipocytes.

Effect of the Arctic terrestrial plant Ranunculus hyperboreus on LPS-induced inflammatory response via MAPK pathways.

The Arctic flora hosts a limited number of species due to its extreme environmental conditions which also yield novel and unique secondary metabolites from withstanding plants. Considering a lack of research on bioactivity potential of Arctic flora, Ranunculus hyperboreus, an Arctic plant, was studied for its anti-inflammatory potential as a part of ongoing research on discovering novel natural bioactive products. Solvent-based fractions (H2O, n-BuOH, 85% aq. MeOH, n-hexane) from R. hyperboreus extract were observed to decrease the elevated nitrate amount during the inflammatory response of lipopolysaccharide-induced mouse macrophage RAW264.7 cells. To some extent, treatment with fractions was able to regulate the expression and protein levels of inflammation-related enzymes, iNOS and COX-2, and pro-inflammatory cytokines, TNF-α, IL-1ß, and IL-6. The most active fractions, H2O and 85% aq. MeOH, were suggested to exert their effect through suppressed activation of MAPK pathways, especially JNK. Based on the studies of same species, phenolic glycosides were suggested to be the main active ingredients. To our knowledge, this is the first report of any bioactivity of R. hyperboreus which could be a valuable source of natural bioactive agents against inflammation.

Crude extract and solvent fractions of Calystegia soldanella induce G1 and S phase arrest of the cell cycle in HepG2 cells.

The representative halophyte Calystegia soldanella (L) Roem. et Schult is a perennial vine herb that grows in coastal dunes throughout South Korea as well as in other regions around the world. This plant has long been used as an edible and medicinal herb to cure rheumatic arthritis, sore throat, dropsy, and scurvy. Some studies have also shown that this plant species exhibits various biological activities. However, there are few studies on cytotoxicity induced by C. soldanella treatment in HepG2 human hepatocellular carcinoma cells. In this study, we investigated the viability of HepG2 cells following treatment with crude extracts and four solvent-partitioned fractions of C. soldanella. Of the crude extract and four solvent fractions tested, treatment with the 85% aqueous methanol (aq. MeOH) fraction resulted in the greatest inhibition of HepG2 cell proliferation. Flow cytometry showed that the 85% aq. MeOH fraction induced a G0/G1 and S phase arrest of the cell cycle progression. The 85% aq. MeOH fraction arrested HepG2 cells at the G0/G1 phase in a concentration-dependent manner, and resulted in decreased expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, CDK6, p21, and p27. Additionally, the 85% aq. MeOH fraction treatment also arrested HepG2 cells in the S phase, with decreased expression of cyclin A, CDK2, and CDC25A. Also, treatment with this fraction reduced the expression of retinoblastoma (RB) protein and the transcription factor E2F. These results suggest that the 85% aq. MeOH fraction exhibits potential anticancer activity in HepG2 cells by inducing G0/G1 and S phase arrest of the cell cycle.

Antioxidant Activity of Oxygen Evolving Enhancer Protein 1 Purified from Capsosiphon fulvescens.

This study was conducted to determine the antioxidant activity of a protein purified from Capsosiphon fulvescens. The purification steps included sodium acetate (pH 6) extraction and diethylaminoethyl-cellulose, reversed phase Shodex C4P-50 column chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that the molecular weight of the purified protein was 33 kDa. The N-terminus and partial peptide amino acid sequence of this protein was identical to the sequence of oxygen evolving enhancer (OEE) 1 protein. The antioxidant activity of the OEE 1 was determined in vitro using a scavenging test with 4 types of reactive oxygen species (ROS), including the 2,2-diphenyl-1-picrylhydrazyl radical, hydroxyl radical, superoxide anion, and hydrogen peroxide (H2 O2 ). OEE 1 had higher H2 O2 scavenging activity, which proved to be the result of enzymatic antioxidants rather than nonenzymatic antioxidants. In addition, OEE 1 showed less H2 O2 -mediated ROS formation in HepG2 cells. In conclusion, this study demonstrates that OEE 1 purified from C. fulvescens is an excellent antioxidant.

PTP1B inhibitory effect of alkyl p-coumarates from Calystegia soldanella.

In this report, the PTP1B inhibitory effect of Calystegia soldanella was investigated. Bioassay-guided fractionation of the crude extracts revealed that the n-hexane fraction had the strongest PTP1B inhibitory effect. Nine known alkyl p-coumarates were isolated from the n-hexane fraction, and each compound was evaluated for its effect on PTP1B. All compounds effectively inhibited PTP1B activity. The IC50 values of the compounds were 3 (10.8 µg/mL) > 2 (15.5 µg/mL) > 7 (26.6 µg/mL) > 1 (37.0 µg/mL) > 8 (41.2 µg/mL) > 9 (43.4 µg/mL) > 5 (44.7 µg/mL) > 4 (> 50 µg/mL) > 6 (> 50 µg/mL).

Metabolic engineering of Clostridium acetobutylicum for butyric acid production with high butyric acid selectivity.

A typical characteristic of the butyric acid-producing Clostridium is coproduction of both butyric and acetic acids. Increasing the butyric acid selectivity important for economical butyric acid production has been rather difficult in clostridia due to their complex metabolic pathways. In this work, Clostridium acetobutylicum was metabolically engineered for highly selective butyric acid production. For this purpose, the second butyrate kinase of C. acetobutylicum encoded by the bukII gene instead of butyrate kinase I encoded by the buk gene was employed. Furthermore, metabolic pathways were engineered to further enhance the NADH-driving force. Batch fermentation of the metabolically engineered C. acetobutylicum strain HCBEKW (pta(-), buk(-), ctfB(-) and adhE1(-)) at pH 6.0 resulted in the production of 32.5g/L of butyric acid with a butyric-to-acetic acid ratio (BA/AA ratio) of 31.3g/g from 83.3g/L of glucose. By further knocking out the hydA gene (encoding hydrogenase) in the HCBEKW strain, the butyric acid titer was not further improved in batch fermentation. However, the BA/AA ratio (28.5g/g) obtained with the HYCBEKW strain (pta(-), buk(-), ctfB(-), adhE1(-) and hydA(-)) was 1.6 times higher than that (18.2g/g) obtained with the HCBEKW strain at pH 5.0, while no improvement was observed at pH 6.0. These results suggested that the buk gene knockout was essential to get a high butyric acid selectivity to acetic acid in C. acetobutylicum.