Structure, anti-tumor activity, and potential anti-tumor mechanism of a fungus polysaccharide from Fomes officinalis.

In our ongoing process of discovering bioactive macromolecules, a homogeneous polysaccharide (FOP80-1) was first purified from Fomes officinalis. FOP80-1 with molecular weight of 4560 Da was mainly composed of →3)-d-Galp-(1→, →4)-ß-d-Manp-(1→, →6)-α-d-Glcp-(1→, →3,6)-d-Glcp-(1→, and t--d-Glcp. Besides the structure features, the anti-tumor activity and potential mechanism of FOP80-1 were also investigated. The cellular and zebrafish experiments revealed that FOP80-1 inhibited tumor proliferation, invasion, and metastasis by increasing ROS, arresting cell cycle, inducing apoptosis, and suppressing angiogenesis. Corresponding to the inhibition of angiogenesis, the surface plasmon resonance (SPR) experiments revealed that FOP80-1 had good affinity with VEGF, a crucial protein to regulate angiogenesis. Molecular docking indicated that FOP80-1 could interact with the protein VEGF.

Perilla frutescens seed oil combined with Anredera cordifolia leaf powder attenuates age-related cognitive decline by reducing serum triglyceride and glucose levels in healthy elderly Japanese individuals: a possible supplement for brain health.

We have shown that Anredera cordifolia extract improves learning and memory in a senescence-accelerated mouse model, and that α-linolenic acid (ALA)-rich Perilla frutescens seed oil (PO) improves brain function in healthy Japanese adults and elderly individuals. Herein, we present a 12-month, randomised, double-blind, parallel-armed intervention trial examining the effects of PO supplementation alone or in combination with A. cordifolia leaf powder on brain function in healthy elderly Japanese individuals. Participants were randomly divided into two groups: the PO group received 1.47 mL PO (0.88 g ALA) daily via soft gelatine capsules, and the POAC group received 1.47 mL PO and 1.12 g A. cordifolia leaf powder (1.46 mg vitexin and 1.12 mg adenosine) daily. After 12 months of intervention, the POAC group showed generally higher cognitive index scores than the PO group. The beneficial effects of combined supplementation on cognitive function were associated with increased ALA and eicosapentaenoic acid levels in red blood cell plasma membranes, increased serum biological antioxidant potential, and decreased serum triglyceride, glucose, and N-(epsilon)-carboxymethyl-lysine (CML), an advanced glycation end-product and biochemical marker of oxidative stress levels. The effects of combined supplementation on cognitive function also showed a significant negative correlation with serum CML levels after 12 months of intervention. Our findings suggest that combined long-term supplementation with PO and A. cordifolia more effectively ameliorates age-related cognitive decline than PO alone. These findings may serve as a basis for the development of new supplements for brain health. Clinical Trial Registry, UMIN000040863.

Perilla seed oil in combination with nobiletin-rich ponkan powder enhances cognitive function in healthy elderly Japanese individuals: a possible supplement for brain health in the elderly.

Perilla (Perilla frutescens) seed oil (PO), rich in α-linolenic acid (ALA), can improve cognitive function in healthy elderly Japanese people. Here, supplements containing either PO alone or PO with nobiletin-rich air-dried immature ponkan powder were examined for their effects on cognitive function in 49 healthy elderly Japanese individuals. Patients were enrolled in a 12-month randomized, double-blind, parallel-armed study. Randomized participants in the PO group received soft gelatin capsules containing 1.47 mL (0.88 g of ALA) of PO daily, and those in the PO + ponkan powder (POPP) group received soft gelatin capsules containing both 1.47 mL of PO and 1.12 g ponkan powder (2.91 mg of nobiletin) daily. At the end of intervention, the POPP group showed significantly higher cognitive index scores than the PO group. The pro-cognitive effects of POPP treatment were accompanied by increases in ALA and docosahexaenoic acid levels in red blood cell plasma membranes, serum brain-derived neurotropic factor (BDNF) levels, and biological antioxidant potential. We demonstrate that 12-month intervention with POPP enhances serum BDNF and antioxidant potential, and may improve age-related cognitive impairment in healthy elderly people by increasing red blood cell ω-3 fatty acid levels. Clinical Trial Registry, UMIN000040863.

A dandelion polysaccharide and its selenium nanoparticles: Structure features and evaluation of anti-tumor activity in zebrafish models.

In this study, an inulin fructan (TMP50-2) with moderate anti-tumor activity was obtained from dandelion. To further improve the anti-tumor activity of TMP50-2, a monodisperse and stable spherical nanoparticle (Tw-TMP-SeNP, 50 nm) was fabricated. Physico-chemical analysis revealed that TMP50-2 and Tween 80 were tightly wrapped on the surface of SeNPs by forming CO⋯Se bonds or through hydrogen bonding interaction (OH⋯Se). In vitro anti-tumor assay showed that Tw-TMP-SeNP treatment could significantly inhibit the proliferation of cancer cells (HepG2, A549, and HeLa) in a dose-dependent manner, while HepG2 cells were more susceptible to Tw-TMP-SeNP with an IC50 value of 46.8 µg/mL. The apoptosis induction of HepG2 cells by Tw-TMP-SeNP was evidenced by increasing the proportion of apoptotic cells ranging from 12.5% to 27.4%. Furthermore, in vivo zebrafish model confirmed the anti-tumor activity of Tw-TMP-SeNP by inhibiting the proliferation and migration of tumor cells as well as the angiogenesis of zebrafish embryos.

Structural analysis and biological effects of a neutral polysaccharide from the fruits of Rosa laevigata.

A neutral water-soluble polysaccharide (RLP50-2) was extracted and purified from the fruits of Rosa laevigata. The absolute molecular weight was determined as 1.26 × 104 g/mol. Monosaccharide composition analysis showed that RLP50-2 mainly consisted of glucose, arabinose, and galactose. Structural analysis revealed that RLP50-2 consisted of →5)-α-L-Araf-(1→, →2,5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→, →6)-α-D-Glcp-(1→, →3,6)-ß-D-Glcp-(1→, →4)-α-D-Galp-(1→, →6)-ß-D-Galp-(1→, →2)-ß-D-Xylp-(1→, terminal α-L-arabinose, and terminal ß-D-mannose. Biological assays showed that RLP50-2 had immunomodulatory activities using cell and zebrafish models. Moreover, RLP50-2 showed significantly antitumor activities by inhibiting tumor cell proliferation and migration and blocking angiogenesis. These results suggested that RLP50-2 could be developed as a potential immunomodulatory agent or antitumor candidate drug in biomedicine field.

Cytotoxic and Antiangiogenetic Xanthones Inhibiting Tumor Proliferation and Metastasis from Garcinia xipshuanbannaensis.

Eight prenylated xanthones including four new analogues were extracted and purified from the leaves of Garcinia xipshuanbannaensis. Multiple techniques including UV, 1D and 2D NMR, and HRESIMS were used to determine the structures of the isolated xanthones. These xanthones were evaluated for their cytotoxicity toward human cancer cells, and compound 4 exhibited activity against HeLa cells. A cytotoxic mechanism examination revealed the active compound induced cell apoptosis by arresting the cell cycle, increasing the levels of ROS, and inhibiting the expression of p-STAT3 in HeLa cells. In in vivo zebrafish experiments, compound 4 was found to block tumor proliferation and migration and have antiangiogenetic activity, and thus seems worthy of further laboratory evaluation.

Isolation, structural elucidation, and immunoregulation properties of an arabinofuranan from the rinds of Garcinia mangostana.

In our search for bioactive polysaccharides as immunomodulatory agents, an arabinofuranan (GMP90-1) was purified and characterized from the rinds of Garcinia mangostana L. GMP90-1 (absolute molecular weight: 5.30 × 103 g/mol) was found to be composed of arabinose, galactose, and rhamnose. The backbone of GMP90-1 was determined as (1→5)-linked α-l-Araf, (1→2,3,5)-linked α-l-Araf, (1→3,5)-linked α-l-Araf, (1→6)-linked ß-d-Galp, and (1→2)-linked α-l-Rhap. Conformational analysis revealed GMP90-1 to exist as a rigid rod structure in sodium chloride solution. To explore its potential as immunomodulatory agents, an in vitro cell screening was performed and GMP90-1 was found to significantly enhance the phagocytic uptake of neutral red and improve the secreted level of nitric oxide (NO), interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α (TNF-α) of macrophages. Furthermore, the cellular immunomodulatory activities were confirmed by the in vivo zebrafish experiment, which suggested that GMP90-1 with immunomodulatory effects could be considered as a potential immunomodulatory for immune diseases.

An active heteropolysaccharide from the rinds of Garcinia mangostana Linn.: Structural characterization and immunomodulation activity evaluation.

A previously undescribed polysaccharide, GMP70-1, was isolated from the rinds of Garcinia mangostana Lin. Physicochemical characterization analysis showed that GMP70-1 (absolute molecular weight: 2.01 × 104 g/mol) is a multi-branched acidic heteropolysaccharide with a compact coil chain conformation in sodium chloride solution. The repeated unit of GMP70-1 was mainly composed of (1 → 5)-linked α-L-Araf, (1 → 3, 5)-linked α-L-Araf, (1 → 2, 4)-linked α-L-Rhap, (1 → 4)-linked ß-D-Galp, terminating with t-α-L-Araf, t-α-D-GalpA, and t-ß-D-Galp. To explore the medicinal potential responsible for the bioactivity of G. mangostana, an immunomodulatory assay was performed. The in vitro cell test showed that GMP70-1 possessed a prominent immunoregulatory activity by enhancing the phagocytic uptake of neutral red and promoting the secretion of nitric oxide (NO), reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1ß of macrophages. Furthermore, an in vivo zebrafish evaluation revealed that the production of ROS and NO was significantly increased after treated with GMP70-1.

A fructan from Anemarrhena asphodeloides Bunge showing neuroprotective and immunoregulatory effects.

A novel polysaccharide, AAP70-1, was isolated from Anemarrhena asphodeloides for the first time. The primary structural analysis revealed that AAP70-1 was composed of glucose and fructose, had an absolute molecular weight of 2720 Da, and contained a (2→6)-linked ß-D-fructofuranose (Fruf) backbone and a (2→1,6)-linked ß-D-Fruf side chain with an internal α-D-glucopyranose (Glcp) in the form of a neokestose. To explore the potential factors responsible for the medicinally relevant bioactivities of A. asphodeloides, a biological assay was performed. Using flow cytometry analysis, AAP70-1 was experimentally shown to have neuroprotective effects, and it can prevent and ameliorate neurological damage via reducing apoptosis. The immunomodulation assay further revealed that AAP70-1 can significantly improve immune function by promoting phagocytic capacity and the secretion of cytokines (IL-6, IL-1ß and TNF-α) in RAW264.7 cells. These results suggest that AAP70-1 has potential as a therapeutic agent for central nervous system diseases or as an immunomodulatory agent.

Clerodane diterpenoids from Casearia kurzii and their cytotoxic activities.

A search for bioactive natural products as anticancer lead compounds resulted in the isolation of one previously undescribed and three known clerodane diterpenoids (1-4) from Casearia kurzii. The structures of these compounds were established by analysis of their NMR, MS, and electronic circular dichroism data. The cytotoxic activities of four compounds against three human cancer cell lines were evaluated. Compound 2 was found to be the most active with an IC50 value of 4.1 µM against HeLa cells, and was selected to investigate the possible cytotoxic mechanism.

Cytotoxic diterpenoids as potential anticancer agents from the twigs of Casearia kurzii.

A search for bioactive natural products as anticancer lead compounds has led to the isolation of five new clerodane diterpenoids (1-5) from the twigs of Casearia kurzii. Their structures were elucidated by extensive analysis of their NMR, IR, and HRESIMS data, and the absolute configurations were determined by experimental and calculated electronic circular dichroism (ECD) data analysis. The isolates were biologically evaluated and showed cytotoxic activities toward human lung cancer cells (A549), human cervical cancer cells (HeLa), and human hepatocellular carcinoma cells (HepG2). The most active compound (5) with an IC50 value of 5.3 µM against HeLa cells, was found to induce apoptosis and arrest the HeLa cell cycle at G0/G1 stage to exert cytotoxic effects.

Cytotoxic clerodane diterpenoids from the leaves of Casearia kurzii.

A phytochemical investigation to obtain bioactive substances as lead compounds or agents for cancer led to the obtainment of six new clerodane diterpenoids, designated as kurzipenes A-F (1-6), from the leaves of Casearia kurzii. Their structures were elucidated on the basis of NMR spectroscopic data analysis and the absolute configurations were confirmed by the time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The cytotoxic activities of compounds 1-6 were evaluated against human lung cancer A549 cell line, human cervical cancer Hela cell line, and human hepatocellular carcinoma HepG2 cell line. Most diterpenoids showed potent cytotoxicities against the three selected cancer cell lines. The preliminary mechanism studies revealed that the most active compound 2, with an IC50 value of 5.3 µM against Hela cells, induced apoptosis and arrested the Hela cell cycle at the G0/G1 stage to exert cytotoxic effects.

Nobiletin Reduces Intracellular and Extracellular ß-Amyloid in iPS Cell-Derived Alzheimer's Disease Model Neurons.

Alzheimer's disease (AD) is the most common cause of dementia, with progressive memory impairment. Recently, neprilysin, a ß-amyloid (Aß)-degrading enzyme has become featured as a drug target for AD. Previously, we identified nobiletin from citrus peels as a natural compound possessing anti-dementia activity. In addition, we demonstrated that nobiletin improved memory in memory-impaired animals and, further, that Aß levels were markedly decreased in the brains of these animals. We demonstrated in vitro that nobiletin up-regulates neprilysin expression and activity in human neuroblastoma cells. However, the action of nobiletin with regard to Aß degradation under in vitro AD pathological conditions remains unclear. In this study, we examined whether nobiletin could enhance the degradation of intra- and extracellular Aß using human induced pluripotent stem cell-derived AD model neurons, which generate an excess of Aß1-42 due to the familial AD presenilin-1 mutation. The neurons were treated in the presence or absence of nobiletin. The results of real-time quantitative RT-PCR indicated that neprilysin mRNA levels were significantly up-regulated by nobiletin. Furthermore, immunostaining with an anti-Aß antibody revealed that nobiletin substantially reduced the intraneuronal content of Aß. Interestingly, the results of Aß1-42 immunoassays confirmed that nobiletin also significantly decreased the levels of Aß1-42 released into the cellular medium. These results suggest that nobiletin enhanced the reduction of intra- and that extracellular Aß levels under AD pathologic conditions, and this is associated with the up-regulation of neprilysin expression. Collectively, nobiletin appears to be a promising novel prophylactic seed drug or functional food for AD.

Unfolding of the myosin head by purealin in glycerol.

Purealin is a small bioactive compound obtained from the marine sponge. The compound modulates various types of ATPase activity of myosin from skeletal muscle, cardiac muscle, and smooth muscle. To elucidate the structural basis of these effects of purealin on myosin ATPases, we examined the effect of purealin on the conformation of skeletal muscle myosin in aqueous solution and in glycerol. Analysis of the circular dichroism spectrum of subfragment 1, a single-headed fragment of myosin, revealed that in 10% glycerol purealin decreased the ß-sheet content of S1, but in aqueous solution it had little effect on the secondary structure of S1. A myosin monomer conforms to two pear-like globular heads attached to a long tail. Electron microscopy observations with rotary shadowing revealed that purealin unfolded each globular head to an extended single strand. The tips of the unfolded strand bound each other and formed a ring in one molecule. These results suggest that binding of purealin affects the critical parameters of myosin folding.

Bioactive Terpenoids from Salvia plebeia: Structures, NO Inhibitory Activities, and Interactions with iNOS.

A phytochemical investigation to obtain new NO inhibitors resulted in the identification of six new (1-6) and four known (7-10) terpenoids from Salvia plebeia. Compounds 1 and 2 are new diterpenoids, 3-5 are new meroditerpenoids, 6-9 are sesquiterpenoids, and 10 is a known meroditerpenoid. The structures of these isolates were determined by routine NMR experiments and X-ray diffraction, as well as the electronic circular dichroism spectra. Compounds 1-4 are diterpenoids carrying an oxygen bridge, and 6 is a rare copane-type sesquiterpenoid with a bridged tricyclic framework. The isolates inhibited NO generation induced by lipopolysaccharide in BV-2 cells. The possible mechanism of NO inhibition of some bioactive compounds was also investigated using molecular docking, which revealed interactions of bioactive compounds with the iNOS protein.

Characterization of diterpenoids from Caesalpinia decapetala and their anti-TMV activities.

Caesalpinia decapetala is a versatile medicinal plant belonging to the Fabaceae plant family. In our survey on plant secondary metabolites to obtain bioactive substances for the development of new agricultural anti-TMV agents, the chemical constituents of C. decapetala were investigated. This investigation led to the isolation of three new and ten known diterpenoids. Their structures including absolute configurations were elucidated based on the extensive NMR spectroscopic data analyses and the time-dependent density functional theory calculations. The following biological screenings revealed that most of these diterpenoids possessed anti-TMV activities.

Nerve growth factor enhances the CRE-dependent transcriptional activity activated by nobiletin in PC12 cells.

Prevention and treatment of Alzheimer disease are urgent problems for elderly people in developed countries. We previously reported that nobiletin, a poly-methoxylated flavone from the citrus peel, improved the symptoms in various types of animal models of memory loss and activated the cAMP responsive element (CRE)-dependent transcription in PC12 cells. Nobiletin activated the cAMP/PKA/MEK/Erk/MAPK signaling pathway without using the TrkA signaling activated by nerve growth factor (NGF). Here, we examined the effect of combination of nobiletin and NGF on the CRE-dependent transcription in PC12 cells. Although NGF alone had little effect on the CRE-dependent transcription, NGF markedly enhanced the CRE-dependent transcription induced by nobiletin. The NGF-induced enhancement was neutralized by a TrkA antagonist, K252a. This effect of NGF was effective on the early signaling event elicited by nobiletin. These results suggested that there was crosstalk between NGF and nobiletin signaling in activating the CRE-dependent transcription in PC12 cells.

Di- and Triterpenoids from the Leaves of Casearia balansae and Neurite Outgrowth Promoting Effects of PC12 Cells.

A bioassay-guided phytochemical investigation of the leaves of Casearia balansae led to the isolation of six new cucurbitane-type triterpenoid derivatives (balanterpenes A-F, 1-6) and four new clerdoane-type diterpenoids (balanterpenes G-J, 7-10). The structures of 1-10 were established on the basis of extensive analysis of NMR spectroscopic data, X-ray crystallography, and experimental and calculated electronic circular dichroism spectra. Compound 1 features a ring-expanded triterpenoid skeleton with the C-19 methyl involved in the ring formation, compound 6 possesses a rare hexanortriterpenoid scaffold, and compounds 7-10 may be four new diterpenoid artifacts presumably formed during the extraction and purification processes. Compounds 3 and 7-10 showed promoting effects on neurite outgrowth of PC12 cells with EC50 values in the range 2.9-10.0 µM.

Characterization and Biological Evaluation of Diterpenoids from Casearia graveolens.

Biologically active substances that promote the neurite outgrowth of nerve cells against neuron degeneration may be useful for the treatment of Alzheimer's disease. In a continuing search for bioactive compounds from plants, an ethyl acetate-soluble extract of the twigs of Casearia graveolens showed moderate stimulatory activity of neurite outgrowth from PC12 cells. Further investigation to obtain bioactive compounds led to the isolation of 10 new clerodane diterpenoids, graveopenes A-J (1-10). Their structures including absolute configurations were elucidated based on analysis of their NMR spectroscopic data and experimental and calculated ECD spectra. Compounds 3-6 and 8 were shown to stimulate NGF-mediated neurite outgrowth from PC12 cells.

Bioactive Diterpenoids from the Leaves of Callicarpa macrophylla.

A phytochemical investigation of the leaves of Callicarpa macrophylla led to the isolation of five new diterpenoids (1-5), macrophypenes A-E, and nine known analogues (6-14). The structures of 1-5 were established on the basis of extensive analysis of NMR spectroscopic data, X-ray diffraction data, and experimental and calculated electronic circular dichroism spectra. Compound 1 is a spiroditerpenoid with a novel skeleton, and compound 5 is a rare ent-abietane diterpenoid possessing a peroxide bridge. Compounds 1, 5-7, and 11-14 stimulate nerve growth factor mediated neurite outgrowth from PC12 cells.