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Complex structure of cyanobacterium Nostoc sp. exopolysaccharide (EPS), with apparent molecular weight 214 × 103 g/mol, can be deduced from its composition. Chemical and NMR analyses found four dominant sugar monomers, namely (1 → 4)-linked α- l -arabinopyranose, β- d -glucopyranose, β- d -xylopyranose and (1 → 3)-linked β- d -mannopyranose, two different uronic acids and a lactyl group, with (1 → 4,6)-linked β- d -glucopyranose as the only branch point suggest a complex structure of this polymer. The dominant uronic acid is α-linked, but it remained unidentified. β- d -Glucuronic acid was present in lower amount. Their position as well as that of lactyl remained undetermined too. Different doses of orally administered EPS in guinea pigs evoked a significant decrease in cough effort and a decrease in airway reactivity. The antitussive efficacy and bronchodilator effect of higher doses of EPS were found to be similar to that of the antitussive drug codeine and the antiasthmatic salbutamol. Without significant cytotoxicity on the RAW 264.7 cells, EPS stimulated the macrophage cells to produce pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and prostaglandins (PGs) and nitric oxide (NO) via induction of COX-2 and iNOS expression, respectively, suggesting that this biopolymer potentiates an early innate immune response and can therefore be used as a new immune modulator.

Background and purpose Glycosylation of phenolic compounds has been reported to increase water-solubility, reduce toxicity, and sometimes give improved or novel pharmacological activities. Present study was aimed to evaluate and compare the beneficial effects of quercetin aglycone (Quer) and its glycosylated derivative, quercetin 3-O-xyloside (Quer-Xyl), against acute pancreatitis (AP). Methods The cellular acute pancreatitis model was established by treating the rat pancreatic acinar cells (AR42J) with lipopolysaccharide (10 µg/ml) and cerulein (10−7 M). The cytotoxicity of Quer or Quer-Xyl on AR42J cells was assessed by MTT assay. Calcium and ROS levels were fluorometrically determined. The ER stress levels (PERK, GRP78), expression levels of amylase and lipase, and apoptotic markers (caspase-3 and -9) were measured by RT-PCR, western blotting, or fluorometric assay. Results While Quer increased the mRNA expressions of AP marker enzymes, amylase and lipase, Quer-Xyl dose-dependently reversed their expressions. Quer-Xyl suppressed intracellular ROS production and both mRNA and protein levels of GRP78 and PERK, which were significantly elevated in cerulein and LPS-treated AR42J cells. Further, RT-PCR and fluorescence assay revealed that Quer-Xyl dose-dependently augmented the mRNA expressions and activities of caspase-3 and -9. Conclusion These results showed that Quer-Xyl, but not Quer, has a significant anti-pancreatitis activity through attenuating intracellular ROS production and ER stress response and enhancing apoptotic cell death, suggesting that it might be useful as a potent functional ingredient in health-beneficial foods or as a therapeutic agent to prevent or treat AP.

Colorectal cancer is the third most diagnosed cancer and a leading cause of cancer death. Dissatisfaction with currently available anti-colorectal cancer drugs caused by unwanted side effects and low efficacy necessitates new therapeutic agents. In the present study, a sulfated glucuronorhamnoxylan polysaccharide (named SPS-CF) purified from a green alga Capsosiphon fulvescens was evaluated for its anti-cancer activity in vitro and in vivo against colorectal cancer. The SPS-CF treatment resulted in a dose-dependent inhibition of the HT-29 human colon cancer cell growth up to 40% at 500 μg/mL. This inhibitory activity was shown to be mediated by upregulation of the cleavage of caspase-8, -9, -3 and poly (ADP-ribose) polymerase (PARP), induction of DNA fragmentation, and disruption of mitochondrial membrane potential (MMP), demonstrating that SPS-CF causes apoptotic death of HT-29 cancer cells though activation of caspase-dependant pathway. Administration of SPS-CF to BALB/c-nude mice bearing HT-29 cell-xenograft tumor also reduced the tumor growth. The results of this study demonstrated that the SPS-CF effectively inhibits the colorectal tumor growth both in vitro and in vivo by induction of apoptotic death of tumor cells, suggesting that it can be a potent ingredient for health-beneficial foods or anti-cancer agents to prevent or ameliorate human colon cancer.

Non-small-cell lung cancer (NSCLC) is the most frequent type of lung cancer with a high mortality rate. Glycosylation of phenolic compounds may increase water-solubility and pharmacological activities and reduce the toxicity of aglycones. This study aimed to evaluate and compare the anticancer effect of aloe emodin 3-O-glucoside (AE3G) and its aglycone, aloe emodin (AE), against NSCLC.A human adenocarcinoma cell line (A549) and other human non-small cell lung carcinoma cell lines (NCI-H460 cells and NCI-H1299 cells) and BALB/c nu/nu xenograft mice harbouring A549 cells were used as the NSCLC models. Inhibition of cell migration, disruption of mitochondrial membrane potential (MMP), DNA fragmentation, and expression levels of apoptotic proteins were measured by western blot, wound healing assay, JC-1 staining, or TUNEL staining. Histopathological changes in tumour tissues were observed by HE and TUNEL staining.With no significant cytotoxicity against noncancerous cells (Vero cells), AE3G (5-50 μM) significantly and more effectively inhibited the growth, attachment, migration, Bcl-2 expression, and activation of MEK/ERK and Akt signalling proteins and induced cytochrome c release and Bax expression in A549 cells than AE. AE3G also significantly decreased the growth of other NSCLC cells, NCI-H460 cells and NCI-H1299 cells. AE3G suppressed the mRNA expression of matrix metalloproteinases, MMP2 and MMP9, and augmented the collapse of the mitochondrial MMP, cleavage of caspases (caspase 9, 8, and 3) and PARP, and DNA fragmentation. Intraperitoneal injection of AE3G (13 and 26 mg/kg/day) reduced the tumour volume and weight and induced apoptotic cell death in tumour tissues of xenograft NSCLC mice.The present study demonstrated that AE3G significantly and more effectively diminished human NSCLC cell growth and migration by triggering mitochondria-dependent intrinsic apoptosis than AE, providing AE3G as a new potent candidate to prevent or treat human NSCLC.

Excessive osteoclast differentiation and/or bone resorptive function causes a gradual loss of bone, leading to the pathogenesis of bone diseases such as osteoporosis (OP). In this study, a sulfated glucuronorhamnoxylan polysaccharide (designated SPS-CF) of the green alga Capsosiphon fulvescens was evaluated for anti-osteoporotic activity using osteoclastic cells differentiated from RAW264.7 macrophages by receptor activator of NF-κB ligand (RANKL) treatment and ovariectomized (OVX) female mice as a postmenopausal OP model. With negligible cytotoxicity, SPS-CF (50 μg/mL) significantly suppressed tartrate-resistant acid phosphatase (TRAP) activity, actin ring formation, and expression of matrix metalloproteinase 9 (MMP-9), cathepsin K, TRAF6, p-Pyk2, c-Cbl, c-Src, gelsolin, carbonic anhydrase II (CA II), and integrin β3, indicating that SPS-CF inhibits the differentiation and bone resorptive function of osteoclasts. Removal of sulfate groups from SPS-CF abolished its anti-osteoclastogenic activities, demonstrating that sulfate groups are critical for its activity. Oral administration of SPS-CF (400 mg/kg/day) to OVX mice significantly augmented the bone mineral density (BMD) and serum osteoprotegerin (OPG)/RANKL ratio. These results demonstrated that SPS-CF exerts significant anti-osteoporotic activity by dampening osteoclastogenesis and bone resorption via downregulation of TRAF6-c-Src-Pyk2-c-Cbl-gelsolin signaling and augmentation of serum OPG/RANKL ratios in OVX mice, suggesting that SPS-CF can be a novel anti-osteoporotic compound for treating postmenopausal OP.

Aim Due to on-going safety concerns or lack of efficacy of currently used medications for the treatment of osteoporosis (OP), identifying new therapeutic agents is an important part of research. In the present study, potential anti-osteoporotic activity of a natural flavonoid glycoside, trilobatin (phloretin 4-O-glucoside, Tri) was evaluated. Material and methods Osteoclastic cells were established by treating the RAW264.7 macrophage cells with RANKL and ovariectomized (OVX) C57BL/6 female mice were used as an animal model of postmenopausal OP. Actin ring formation, expression levels of osteoclastogenic marker genes and bone resorptive proteins were measured by RT-PCR, western blot, or fluorometric assays. Bone mineral density (BMD) was determined by pDEXA densitometric measurement and serum osteoprotegerin (OPG) and RANKL were measured by ELISA. Key finding Tri (5–20 μM) significantly inhibited osteoclast formation and actin ring formation in RANKL-induced osteoclasts. Tri attenuated expression of osteoclastogenic genes (MMP-9 and cathepsin K), bone resorptive proteins (CA II and integrin β3), and osteoclastogenic signalling proteins (TRAF6, p-Pyk2, c-Cbl, and c-Src). Oral administration of Tri to OVX mice augmented BMD and serum OPG/RANKL ratio. Interestingly, while Tri and phloretin aglycone (Phl) showed similar levels of in vitro anti-osteoclastogenic activity, Tri more potently ameliorated bone loss than Phl in OVX mice. Significance This study demonstrated that Tri inhibits osteoclastic cell differentiation and bone resorption by down-regulating the expression of osteoclastogenic marker genes and signalling proteins, bone resorptive proteins, and by augmenting serum OPG/RANKL ratio, suggesting that Tri can be a novel anti-osteoporotic compound for treating senile and postmenopausal OP.

Whereas the fruits and a small portion of root bark of Lycium trees are commonly marketed in Korea as traditional medicine or functional foods, majority of their whole roots have been largely discarded. To develop the whole root of these plants as more value-added materials, this study aimed to evaluate the potential immunostimulating activity of a water extract (GTR-101) from L. chinense Miller roots using macrophages. The GTR-101 (0-500 μg/ml) significantly, dose-dependently increased the secretion of pro-inflammatory cytokines (TNF-α and IL-6), chemokines (RANTES and MIP-1α), nitric oxide, and the expression of inducible nitric oxide synthase, and activated the Akt, NF-κB, and MAPKs (ERK and p38) signaling proteins. GTR-101 also significantly enhanced the phagocytic activity of RAW 264.7 cells and bone marrow-derived macrophages. These results suggest that GTR-101 stimulates the early innate immunity via inducing the pro-inflammatory cytokine and chemokine secretion and enhancing the phagocytic activity of macrophages. PRACTICAL APPLICATIONS: The GTR-101 prepared from L. chinense Miller roots may be useful for enhancing body's defense systems especially in the elderly and cancer patients with an impaired or reduced immune response and may thus be effectively used as a natural immunostimulating ingredient in health foods or complementary medicine.

Lung cancer is diagnosed at an advanced stage due to its unrecognized symptoms, resulting in high mortality. In recent decades, research into the development of an early diagnostic method for lung cancer has expanded in order to overcome the high mortality rate. Calpain 2 (CAPN2) has been suggested as a tumor marker linked to angiogenesis, cell proliferation, and migration in non-small cell lung cancer. In this study, CAPN2 enzyme-activatable near-infrared peptide sensor linked to human serum albumin (HSA–CAPN2) was developed. Intracellular localization and strong recovered fluorescence signals of HSA–CAPN2 were observed in in vitro experiments using A549-Luc cells, and signal recovery was inhibited by ALLN (a CAPN2 inhibitor). In vivo distribution and signal recovery evaluations performed using A549-Luc cell xenograft mice revealed that HSA–CAPN2 accumulated in the tumor region and produced high fluorescent signal recovery. Three-dimensional reconstructed images using single-plane illumination microscopy...

Nonsmall cell lung cancer (NSCLC) is a leading cause of global cancer mortality. Recently, combinatorial treatment approaches have shown promise as they better address tumor heterogeneity. However, drug pharmacokinetics and tissue distribution differences remain problematic. To overcome these issues and improve therapeutic efficacies, the use of nanomedicines has been suggested. We devised a CD44 receptor target hyaluronic acid (HA)-decorated glycol chitosan (GC) nanoparticle which is conjugated to doxorubicin (DOX) by a pH-sensitive linker and coloaded celecoxib (CXB; HA-GC-DOX/CXB). Successful chemical conjugation of GC to DOX was confirmed and HA-GC-DOX/CXB showed ∼150 nm of uniform spherical shape. HA-GC-DOX/CXB were stable at pH 7.4 but steadily increased in size and released drugs at pH 6.0 and 4.0. In vitro NSCLC cells showed that DOX and CXB combination therapy has synergism in both free drug and nanoparticle formulation. In vivo NSCLC xenograft mice showed DOX and CXB exhibited a synergistic tumor suppressive effect in HA-GC-DOX/CXB. Furthermore, HA-GC-DOX/CXB dramatically inhibited tumor growth compared to other treatments as well as suppressed inflammation and metastasis-related gene/protein in the tumor tissues. Our findings demonstrate HA-GC-DOX/CXB is a potential anticancer therapy that controlled release under acidic tumor microenvironments and enhanced CD44 overexpressed tumor target efficacy.

Potential anti-obesity effects of quinizarin, a plant anthraquinone, were investigated using 3 T3-L1 preadipocyte cells and high-fat diet (HD)-induced obese mice.Cell viability was determined using the MTT assay. Triglyceride (TG) and lipid accumulation were determined using a TG assay kit and Oil Red O staining, respectively. Adipogenic, lipogenic, and lipolytic gene and protein expression was measured by RT-PCR or Western blot. Serum biochemical indices, including cholesterol and blood glucose, in HD-fed obese mice were determined using corresponding assay kits. Histological analysis was performed with haematoxylin and eosin (HE) staining.Quinizarin (0-10 μM) significantly reduced intracellular TG and lipid droplets during the differentiation of preadipocytes. Quinizarin significantly suppressed the expression of adipocyte differentiation marker proteins, such as CCAAT/enhancer-binding protein β (C/EBP-β), C/EBP-α, PPAR-γ, and aP2, and lipogenic marker proteins, including SREBP1c, SREBP2, fatty acid synthase (FAS), and acetyl-CoA carboxylase 1 (ACC1), reduced ACC2 expression and increased carnitine palmitoyltransferase 1 (CPT1) expression. Oral administration of quinizarin (15-30 mg/kg/day) to HD-fed mice for 6 weeks reduced the body weight gain and size of liver adipocytes and epididymal fat tissues, with significant reductions in liver TG and serum total cholesterol, blood glucose, LDL, and HDL levels.The results of this study indicated that quinizarin exerts anti-obesity effects by inhibiting both adipogenesis and lipogenesis and stimulating lipolysis in vitro and in vivo mainly by downregulating the SREBP signalling pathway; thus, it might be a potent candidate as a health-beneficial food or therapeutic agent to prevent or treat obesity.

Present study was aimed to investigate the potential anti-obesity effects of maysin, a major flavonoid of corn silk, in vitro and in vivo using 3T3-L1 preadipocyte cells and C57BL/6 mice. Maysin decreased the levels of intracellular lipid droplets and triglycerides (TG), and down-regulated the protein expression levels of C/EBP-β, C/EBP-α, PPAR-γ, and aP2 in 3T3-L1 preadipocyte cells, suggesting that maysin inhibits lipid accumulation and adipocyte differentiation. In addition, maysin was shown to induce the apoptotic cell death in 3T3-L1 preadipocyte cells via activation of caspase cascades and mitochondrial dysfunction, which may ultimately lead to reduction of adipose tissue mass. Furthermore, oral administration of maysin (25mg/kg body weight) decreased weight gain and epididymal fat weight in high-fat diet (HFD)-fed C57BL/6 mice. Administration of maysin also reduced serum levels of TG, total-cholesterol, LDL-cholesterol, and glucose. Taken collectively, these results suggest for the first time that the purified maysin exerts an anti-obesity effect in vitro and in vivo. These observations may support the applicability of maysin as a potent functional ingredient in health-beneficial foods or as a therapeutic agent to prevent or treat obesity.

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Quercetin is a natural plant flavonoid that has been reported to possess a wide range of beneficial health effects, including anti-cancer and anti-inflammatory activities. Glycosylation of natural flavonoids with various sugar moieties can affect their physical, chemical, and biological properties. In this study, quercetin 3-O-xyloside (Quer-xyl) was enzymatically synthesized, and the immunomodulatory activities of quercetin and Quer-xyl were evaluated and compared. The results showed that Quer-xyl more effectively induced the secretion of TNF-α and IL-6 than quercetin by 2.5 and 1.5-fold, respectively. Quer-xyl dose-dependently induced the inducible nitric oxide synthase (iNOS) expression and increased the production of nitric oxide (NO) 1.3-fold more than quercetin. Quer-xyl also increased the phosphorylation of ASK1 and MAPKs (JNK and p38). Treatment with NQDI-1 (an inhibitor of ASK1) significantly attenuated the Quer-xyl-induced up-regulation of TNF-α secretion. The activation and subsequent nuclear translocation of NF-κB were substantially enhanced upon treatment with Quer-xyl (2.5-20 μM), while NQDI-1 treatment blocked the nuclear translocation of NF-κB. These results demonstrated that Quer-xyl can enhance the early innate immunity more effectively than quercetin by activating macrophages to secrete TNF-α and IL-6 through up-regulation of the redox-dependent ASK1/MAPK/NF-κB signaling pathway, suggesting for the first time that Quer-xyl may represent a new immunostimulator.

Rapid pathogen testing is expected to play a critical role in infection control and in limiting epidemics. Smartphones equipped with state-of-the-art computing and imaging technologies have emerged as new point-of-use (POU) sensing platforms. We herein report a new assay format for fast, sensitive and portable detection of avian influenza-associated antibodies.

Emodin (Emo) is a natural plant anthraquinone derivative with a wide spectrum of pharmacological properties, including anticancer, antioxidant, and hepatoprotective activities. Glycosylation of natural anthraquinones with various sugar moieties can affect their physical, chemical, and biological functions. In this study, the potential immunomodulatory activities of Emo and its glycosylated derivative, emodin 8-O-glucoside (E8G), were evaluated and compared using murine macrophage RAW264.7 cells and human monocytic THP-1 cells. The results showed that E8G (20 μM) induced the secretion of TNF-α and IL-6 from RAW264.7 cells more effectively than unglycosylated Emo aglycone, by 4.9- and 1.6-fold, respectively, with no significant cytotoxicity in the concentration range tested (up to 20 μM). E8G (2.5–20 μM) significantly and dose-dependently induced inducible nitric oxide synthase (iNOS) expression by up to 3.2-fold compared to that of untreated control following a remarkable increase in nitric oxide (NO) production. E8G also significantly increased the expression of TLR-2 mRNA and the phosphorylation of MAPKs (JNK and p38). The activation and subsequent nuclear translocation of NF-κB was substantially enhanced upon treatment with E8G (2.5–20 μM). Moreover, E8G markedly induced macrophage-mediated phagocytosis of apoptotic Jurkat T cells. These results demonstrated that E8G far more strongly stimulates the secretion of proinflammatory cytokines, such as TNF-α and IL-6, and NO production from macrophages through upregulation of the TLR-2/MAPK/NF-κB signalling pathway than its nonglycosylated form, Emo aglycone. These results suggest for the first time that E8G may represent a novel immunomodulator, enhancing the early innate immunity.

Low molecular weight mannogalactofucans (LMMGFs) prepared by enzymatic degradation of high molecular weight Undaria galactofucan (MF) were evaluated for their anti-cancer effects against human prostate cancer. Correlation NMR and linkage analyses confirmed that LMMGFs consist mainly of α-fucose and β-galactose units: α-fucose units are 1,3-linked; β-galactose units are terminal, 1,3- and/or 1,6-linked; both sugars are partially sulphated, fucose at positions O-2 and/or O-4 and galactose at O-3. Mannose residue, as a minor sugar, presents as the 1,4-linked terminal units. LMMGFs more significantly induced cell cycle arrest at the G0/G1 phase and cell death via suppression of the Akt/GSK-3β/β-catenin pathway than MF in human PC-3 prostate cancer cells. LMMGFs upregulated mRNA expression of death receptor-5 (DR-5), the ratio of Bax to Bcl-2, the cleavage of caspases and PARP, the depolarisation of mitochondrial membrane potential, and ROS generation. LMMGFs (200-400 mg/kg) effectively reduced both tumour volume and size in a xenografted mouse model. These results demonstrated that LMMGFs attenuate the growth of human prostate cancer cells both in vitro and in vivo, suggesting that LMMGFs can be used as a potent functional ingredient in health-beneficial foods or as a therapeutic agent to prevent or treat androgen-independent human prostate cancer. Graphical Abstract.

Although ginseng marc is a by-product obtained during manufacturing of various commercial ginseng products and has been routinely discarded as a waste, it still contains considerable amounts of potential bioactive compounds, including saponins and polysaccharides. Previously, we reported that ginseng oligosaccharides derived from ginseng marc polysaccharides by enzymatic hydrolysis exert immunostimulatory activities in macrophages and these activated macrophages are in turn able to inhibit the growth of skin melanoma cells by inducing apoptosis. In the present study, a more detailed investigation of the immunostimulatory activity and underlying action mechanisms of an enzymatic hydrolysate (GEH) containing these oligosaccharides derived from ginseng marc polysaccharides was performed. The levels of proinflammatory cytokines and anti-inflammatory cytokines were measured in GEH-stimulated RAW264.7 macrophages using RT-PCR analysis and ELISA. The expression levels of Toll-like receptor 2 (TLR2) and TLR4, Dectin-1, and MerTK were measured by RT-PCR analysis or western blot analysis, and the phagocytic activities of GEH-challenged bone marrow-derived macrophages toward apoptotic Jurkat cells were assayed using fluorescence microscopy. GEH induced the production of both proinflammatory cytokines TNF-α and IL-6, and anti-inflammatory cytokine IL-10 in RAW 264.7 cells. The expression of the TLR2 and MerTK mRNAs was increased upon GEH treatment. Phagocytosis of apoptotic Jurkat cells was enhanced in GEH-treated macrophages. Based on the results, this enzymatic hydrolysate (GEH) containing oligosaccharides exerts immunostimulatory effects by maintaining the balance between M1 and M2 cytokines, facilitating macrophage activation and contributing to the efficient phagocytosis of apoptotic cells. Therefore, the GEH could be developed as value-added, health-beneficial food materials with immunostimulatory effects.

Panax ginseng C.A. Meyer has been traditionally consumed to prevent or treat various medical disorders due to its diverse health benefits. Polysaccharides isolated from Panax ginseng have been known to possess various pharmacological activities, including immune modulating, anti-diabetic, and anti-obesity properties. Despite the increasing number of reports on the bioactivities of ginseng polysaccharides, little is known regarding the medicinal potential of ginseng-derived oligosaccharides. In this study, we prepared a lower-molecular weight oligosaccharide (GOS, MW. 2.2kDa) from ginseng polysaccharides (MW. 11-605kDa) by enzymatic degradation and evaluated for its immunostimulating activities in RAW 264.7 murine macrophage cells. GOS was shown to be a glucan type oligosaccharide mainly containing glucose residues (97.48 in molar %). Treatment with GOS (100-500μg/ml) dose-dependently enhanced the production of TNF-α, IL-6, and NO in RAW 264.7 cells. Western blot analysis indicated that GOS dose-dependently induced the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), p38, and nuclear factor κB (NFκB), which are upstream signalling molecules for cytokine production. While GOS was not cytotoxic to the RAW 264.7 macrophage cells at the concentration tested (up to 1000μg/ml), when B16F10 melanoma cells were co-cultured with the GOS-activated macrophages, the cell viability of melanoma cells was dose-dependently decreased through the induction of apoptotic cell death. Taken together, these results suggested that ginseng marc-derived GOS has anti-cancer activity in vitro against melanoma cells by potentiating macrophage function.

Lanthanide-doped upconverting nanoparticles (UCNPs) have recently attracted enormous attention in the field of biological imaging owing to their unique optical properties: (1) efficient upconversion photoluminescence, which is intense enough to be detected at the single-particle level with a (nonscanning) wide-field microscope setup equipped with a continuous wave (CW) near-infrared (NIR) laser (980 nm), and (2) resistance to photoblinking and photobleaching. Moreover, the use of NIR excitation minimizes adverse photoinduced effects such as cellular photodamage and the autofluorescence background. Finally, the cytotoxicity of UCNPs is much lower than that of other nanoparticle systems. All these advantages can be exploited simultaneously without any conflicts, which enables the establishment of a novel UCNP-based platform for wide-field two-photon microscopy. UCNPs are also useful for multimodal in vivo imaging because simple variations in the composition of the lattice atoms and dopant ions integrated into the particles can be easily implemented, yielding various distinct biomedical activities relevant to magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET). These multiple functions embedded in a single type of UCNPs play a crucial role in precise disease diagnosis. The application of UCNPs is extended to therapeutic fields such as photodynamic and photothermal cancer therapies through advanced surface conjugation schemes.

Glycosylation of natural flavonoids with various sugar moieties can affect their physicochemical and pharmacological properties. In this study, the plant flavonoids quercetin aglycon (Quer) and quercetin 3-O-glucoside (Q3G) were evaluated and compared for their potential anti-obesity effects. The Q3G dose-dependently reduced the TG contents and lipid accumulation in 3T3-L1 adipocyte cells, by 52% and 60% at 20μM, respectively, compared to differentiated control (100%), which were 1.6-fold and 2.4-fold higher reduction than Quer. The Q3G (20μM) also more significantly reduced the expression of adipogenic markers such as C/EBP-β, C/EBP-α, PPAR-γ, and aP2 than Quer, indicating that the Q3G suppresses both adipocyte differentiation and lipogenesis more effectively than Quer in vitro. Comparing to those in the high-fat diet (HFD) fed mice control group for 10 weeks, both the body and liver weights and the size of adipocytes in epididymal adipose tissues were significantly reduced in HFD mice fed with Q3G for another 6 weeks (30mg/kg body weight by oral administration), accompanied by the reductions of TG, total cholesterol, and HDL-cholesterol in serum. The Q3G also reduced the levels of the lipid metabolism-associated proteins, PPAR-γ, SREBP-1c, and FAS in the liver tissues. These results clearly demonstrated that Q3G exhibits a stronger anti-obesity effect than Quer and its anti-obesity effect is mediated via inhibition of adipocyte differentiation and lipogenesis, decreasing serum lipid levels by altering hepatic lipid metabolism, and reducing body weight gain. The results of this study suggest that the Q3G, but not Quer, can be a potent functional ingredient of beneficial health foods or a therapeutic agent to prevent or treat obesity.

A water-soluble polysaccharide (JS-MP-1) was isolated and purified from the Korean mulberry fruits Oddi (Morus alba L.) by crushing the fresh fruits then performing ethanol precipitation and DEAE-cellulose ion exchange chromatography. The neutral monosaccharide composition of the purified JS-MP-1 was determined to be composed mainly of galactose (37.6%, in mole percent), arabinose (36.3%), and rhamnose (18.4%), while other major sugars such as glucose, xylose, mannose, and fucose were present as minor components. HPLC analysis revealed that JS-MP-1 contains both galacturonic acid (GalA) and glucuronic acid (GlcA) at approximately 4:1 in mole percent. Monosaccharide composition, Fourier-transform infrared (FTIR) analysis, biochemical analysis, and elemental analysis suggested that JS-MP-1 is an acidic heteropolysaccharide, most likely a rhamnoarabinogalacturonan type plant pectic polysaccharide, with an apparent molecular mass of 1600 kDa containing no, or if any, negligible level of sulfate esters and proteins. Enzyme-Linked Immunosorbent Assay and RT-PCR analysis demonstrated that JS-MP-1 significantly stimulates murine RAW264.7 macrophage cells to release chemokines (RANTES and MIP-1α) and proinflammatory cytokines (TNF-α and IL-6) and to induce the expression of iNOS and COX-2, which are responsible for the production of NO and prostaglandin PGE2, respectively. These results suggest that the mulberry fruit-derived polysaccharide JS-MP-1 can act as a potent immunomodulator, and these observations may support the applicability of this polysaccharide as an immunotherapeutic adjuvant or the water extracts of the mulberry fruit as a beneficial health food.

Aims Anti-allergic effects and action mechanism of phloretin (Phl) and biochanin A (BioA) on the IgE–antigen complex-mediated allergic responses in rat basophilic leukemia RBL-2H3 cells were investigated. Main methods Cell viability, formation of reactive oxygen species (ROS), DPPH radical-scavenging activity, β-hexosaminidase release, production of interleukin (IL)-4, IL-13, and tumor necrosis factor-alpha (TNF-α) and phosphorylation of Akt and mitogen-activated protein kinase (MAPK) were determined by MTT assay, 2,7-dichlorofluorescein diacetate (DCF-DA) assay, DPPH radical-scavenging assay, reverse transcriptase polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and western blot analysis, respectively. Key findings Ph1 and BioA dose-dependently inhibited the formation of ROS and the release of β-hexosaminidase from the RBL-2H3 cells and also showed DPPH radical-scavenging activity. Ph1 and BioA suppressed the antigen-induced phosphorylation of the downstream signaling intermediates, including MAPK and Akt, which are critical for the production of pro-inflammatory cytokines, and also significantly attenuated the production of IgE-mediated pro-inflammatory cytokines, such as IL-4, IL-13, and TNF-α. Significance Phloretin and biochanin A attenuate the degranulation and allergic cytokine production through inhibition of intracellular ROS production and the phosphorylation of Akt and the MAPKs, such as ERK1/2, p38, and JNK. The results of this study suggested that these two plant flavonoids may have potent anti-allergic activity in vitro.

Low-molecular-weight mannogalactofucans (LMMGFs, Undaria pinnatifida sporophyll galactofucan (MF) and evaluated or their antiviral activities and underlying action mechanisms against herpes simplex virus type 1 (HSV-1). The 50% inhibitory concentrations (IC 50 ) of LMMGFs and MF were 2.64 and 2.42 μg/mL, respectively. LMMGFs inhibited the viral entry on the host cell surface and also exhibited inhibitory activity directly against viral particles, as observed in a virucidal assay. LMMGFs dose-dependently enhanced the mRNA expression of Toll-like receptor 2 (TLR2) and stimulated the phosphorylation of Akt and JNK in Vero cells. These results clearly demonstrated that LMMGFs use TLR2 as their receptor, preventing HSV-1 infection on the host cell surface and antagonizing viral adsorption via TLR2 pathway activation in Vero cells.

Theprerequisiteforthesuccessfulbiomedicaluseofnanoparticles is their colloidal stability in harsh biologicalenvironments. One main approach to render nanoparticleswater-dispersible is replacing the hydrophobic cappingligands with hydrophilic ones that harbor anchoring groupssuch as carboxylic acids, thiols, phosphines, and amines

Uniform and extremely small-sized iron oxide nanoparticles (ESIONs) of4 nm were synthesized via the thermal decomposition of iron-oleate complex in the presence of oleyl alcohol. Oleyl alcohol lowered the reaction temperature by reducing iron-oleate complex, resulting in the production of small-sized nanoparticles. XRD pattern of 3 nm-sized nanoparticles revealed maghemite crystal structure. These nanoparticles exhibited very low magnetization derived from the spin-canting effect. The hydrophobic nanoparticles can be easily transformed to water-dispersible and biocompatible nanoparticles by capping with the poly(ethylene glycol)-derivatized phosphine oxide (PO-PEG) ligands. Toxic response was not observed with Fe concentration up to 100 μg/mL in MTT cell proliferation assay of POPEG-capped 3 nm-sized iron oxide nanoparticles. The 3 nm-sized nanoparticles exhibited a high r(1) relaxivity of 4.78 mM(-1) s(-1) and low r(2)/r(1) ratio of 6.12, demonstrating that ESIONs can be efficient T(1) contrast agents. The high r(1) relaxivities of ESIONs can be attributed to the large number of surface Fe(3+) ions with 5 unpaired valence electrons. In the in vivo T(1)-weighted magnetic resonance imaging (MRI), ESIONs showed longer circulation time than the clinically used gadolinium complex-based contrast agent, enabling high-resolution imaging. High-resolution blood pool MR imaging using ESIONs enabled clear observation of various blood vessels with sizes down to 0.2 mm. These results demonstrate the potential of ESIONs as T(1) MRI contrast agents in clinical settings.

Trypsin-coated magnetic nanoparticles (EC-TR/NPs), prepared via a simple multilayer random crosslinking of the trypsin molecules onto magnetic nanoparticles, were highly stable and could be easily captured using a magnet after the digestion was complete. EC-TR/NPs showed a negligible loss of trypsin activity after multiple uses and continuous shaking, whereas the conventional immobilization of covalently attached trypsin on NPs resulted in a rapid inactivation under the same conditions due to the denaturation and autolysis of trypsin. A single model protein, a five-protein mixture, and a whole mouse brain proteome were digested at atmospheric pressure and 37°C for 12 h or in combination with pressure cycling technology at room temperature for 1 min. In all cases, EC-TR/NPs performed equally to or better than free trypsin in terms of both the identified peptide/protein number and the digestion reproducibility. In addition, the concomitant use of EC-TR/NPs and pressure cycling technology resulted in very rapid (∼1 min) and efficient digestions with more reproducible digestion results.

A water-soluble polysaccharide (SPS-CF) was isolated and purified from Korean Capsosiphon fulvescens by dilute acid extraction, ethanol precipitation, and DEAE-cellulose ion exchange chromatography. The purified SPS-CF was shown to be a glucuronogalactomannan with a molecular mass of 385 kDa and the monosaccharide composition of the SPS-CF was determined to be mannose (55.4% in mole percentage), galactose (25.3%), glucuronic acid (16.3%), and arabinose (0.8%). Fourier-transform infrared and elemental analysis indicated that the purified SPS-CF is a sulfated polysaccharide containing significant amount of sulfate esters (5.7% in mass). Enzyme Linked Immunosorbent Assay showed that the SPS-CF significantly stimulates the release of the pro-inflammatory cytokines, TNF-alpha and IL-6, in a dose-dependent manner. RT-PCR analysis demonstrated that the SPS-CF also induced a more than two-fold increase in the expression of iNOS and COX-2, responsible for the induction of NO and PGE2, respectively, at 5 microg/ml in RAW264.7 murine macrophages. These results suggest that the sulfated SPS-CF isolated from C. fulvescens has potent immunostimulating activity.

This study examined the estrogenic activity produced by aqueous extracts of silkworm (Bombyx mori) pupae in ovariectomized (OVX) rats. The components of silkworm pupae were extracted in distilled water at room temperature for 6 hours. The ovaries of six-week old female rats were then bilaterally removed. One week after OVX, the animals were treated with 200, 400 or 600 mg/kg/day of silkworm pupae extracts. The body weights of the OVX rats increased remarkably compared to the control rats, however their relative uterus weights to body weights decreased significantly. Treatment with the aqueous extracts of silkworm pupae dramatically improved the decreased uterus weights of OVX rats, with the highest increase observed in treatment with 200 mg/kg/day of the aqueous extracts. Additionally, treatment with aqueous extracts (200 mg/kg/day) of silkworm pupae significantly elevated the serum 17β-estradiol contents of OVX rats when compared to the control animals. To examine the toxic effects of silkworm pupae on the hepatic functions of OVX rats, the levels of serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) were measured. The serum GOT and GPT levels did not change in response to the administration of aqueous extracts (200, 400 and 600 mg/kg/day) for 4-weeks. Taken together, these results suggest that the aqueous extracts of silkworm pupae may have estrogenic activity, which suggests that silkworm pupae may be useful in the prevention and/or treatment of menopausal disorders caused by deficiencies in female sexual hormones, including estrogen.

When cellular glucose concentrations fall below normal levels, in general the extent of protein O-GlcNAc modification (O-GlcNAcylation) decreases. However, recent reports demonstrated increased O-GlcNAcylation by glucose deprivation in HepG2 and Neuro-2a cells. Here, we report increased O-GlcNAcylation in non-small cell lung carcinoma A549 cells and various other cells in response to glucose deprivation. Although the level of O-GlcNAc transferase was unchanged, the enzyme contained less O-GlcNAc, and its activity was increased. Moreover, O-GlcNAcase activity was reduced. The studied cells contain glycogen, and we show that its degradation in response to glucose deprivation provides a source for UDP-GlcNAc required for increased O-GlcNAcylation under this condition. This required active glycogen phosphorylase and resulted in increased glutamine:fructose-6-phosphate amidotransferase, the first and rate-limiting enzyme in the hexosamine biosynthetic pathway. Interestingly, glucose deprivation reduced the amount of phosphofructokinase 1, a regulatory glycolytic enzyme, and blocked ATP synthesis. These findings suggest that glycogen is the source for increased O-GlcNAcylation but not for generating ATP in response to glucose deprivation and that this may be useful for cancer cells to survive.

Nanometer-sized colloidal particles (nanoparticles) have been extensively used in biomedical applications as a result of their many useful electronic, optical, and magnetic properties that are derived from their nanometer size and composition. Semiconductor nanoparticles (also known as quantum dots) have been applied as fluorescent probes for cell labeling in optical imaging, and gold nanoparticles derivatized with oligonucleotides have been used for sensing complementary DNA strands. Magnetic nanoparticles have been applied to contrast-enhancement agents for magnetic resonance imaging (MRI), magnetic carriers for drug-delivery systems, biosensors, and bioseparation. MRI is one of the most powerful imaging techniques for living organisms as it provides images with excellent anatomical details based on soft-tissue contrast and functional information in a non-invasive and real-time monitoring manner. MRI has further advanced by the development of contrast agents that enable more specific and clearer images and enlargements of detectable organs and systems, leading to a wide scope of applications of MRI not only for diagnostic radiology but also for therapeutic medicine. Current MRI contrast agents are in the form of either paramagnetic complexes or magnetic nanoparticles. Paramagnetic complexes, which are usually gadolinium (Gd) or manganese (Mn) chelates, accelerate longitudinal (T1) relaxation of water protons and exert bright contrast in regions where the complexes localize. For instance, gadolinium diethylenetriaminepentaacetate (Gd-DTPA) has been the most widely used of such complexes and its main clinical applications are focused on detecting the breakage of the blood-brain barrier (BBB) and changes in vascularity, flow dynamics, and perfusion. Manganese-enhanced MRI (MEMRI), which uses manganese ion (Mn) as a T1 contrast agent, is applicable to animals only owing to the toxicity of Mn when it accumulates excessively in tissues and despite the increasing appreciation of this technique in neuroscience research. The recent development of molecular and cellular imaging to help visualize disease-specific biomarkers at the molecular and cellular levels has led to an increased interest in magnetic nanoparticles as MRI contrast agents. In particular, superparamagnetic iron oxide (SPIO) has emerged as the prevailing agent so far. 10] However, the negative contrast effect and magnetic susceptibility artifacts of iron oxide nanoparticles are significant drawbacks of using SPIO in MRI. The resulting dark signal can mislead the clinical diagnosis in T2-weighted MRI because the signal is often confused with the signals from bleeding, calcification, or metal deposits, and the susceptibility artifacts distort the background image. For the extensive applications of MRI to diagnostic radiology and therapeutic medicine and to overcome the [*] Prof. J. H. Lee, Prof. S. T. Kim, Prof. S.-H. Kim Department of Radiology, Samsung Medical Center Sungkyunkwan University School of Medicine Seoul 135-710 (Korea) Fax: (+82)2-3410-0084 E-mail: junghee42.lee@smc.samsung.co.kr

A polyhydric alcohol (PAL) was isolated from Taxus cuspidata and its immunostimulatory activities were assessed. The primary monosaccharide composition of the PAL was determined to be glucose, where HPAEC analysis showed no significant amount of any other sugars. However, glycerol and xylitol were identified as the main sugar alcohols. Fourier-transform infrared (FT-IR) analysis indicated that the purified PAL is a complex glycitol, which structurally contains significant amount of hydroxyl groups. MALDI-TOF mass spectroscopy also demonstrated that PAL is a complex glycitol built in hexose polymerization. Enzyme linked immunosorbent assay showed that the PAL stimulates the release of the proinflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. Furthermore, treatment of RAW 264.7 cells with PAL for 24h remarkably increased the phosphorylation levels of ERK, p38 and JNK in a dose-dependent manner, whereas the total protein levels of ERK (t-ERK), p38 (t-p38) and JNK (t-JNK) remained unchanged. These results clearly demonstrate that PAL stimulates the immune response in RAW 264.7 cells through the activation of MAPKs (ERK, p38 and JNK) signaling pathway. To the best of our knowledge, this is the first study to demonstrate the primary structure and immune-stimulating activities of PAL from the fruit of T. cuspidata.

Corn silk (CS) has long been consumed as a traditional herb in Korea. Maysin is a major flavonoid of CS. The effects of maysin on macrophage activation were evaluated, using the murine macrophage RAW 264.7 cells. Maysin was isolated from CS by methanol extraction, and preparative C18 reverse phase column chromatography. Maysin was nontoxic up to 100 μg/ml, and dose-dependently increased TNF-α secretion and iNOS production by 11.2- and 4.2-fold, respectively, compared to untreated control. The activation and subsequent nuclear translocation of NF-κB was substantially enhanced upon treatment with maysin (1-100 μg/ml). Maysin also stimulated the phosphorylation of Akt and MAPKs (ERK, JNK). These results indicated that maysin activates macrophages to secrete TNF-α and induce iNOS expression, via the activation of the Akt, NF-κB and MAPKs signaling pathways. These results suggest for the first time that maysin can be a new immunomodulator, enhancing the early innate immunity. [BMB Reports 2014; 47(7): 382-387]

Prenylated proteins have been shown to function in important cellular regulatory processes including signal transduction. The enzymes involved in protein prenylation, farnesyl transferase and geranylgeranyl transferase, have been recent targets for development of cancer chemotherapeutics. We have initiated a systematic study of protein prenyl transferases of the malaria parasite, Plasmodium falciparum, to determine whether these enzymes can be developed as targets for antimalarial chemotherapy. We report here the identification of protein farnesyl transferase and protein geranylgeranyl transferase-I in the malaria parasite, P. falciparum. The farnesyl transferase has been partially purified from the cytosolic fraction through ammonium sulfate precipitation and Mono-Q chromatography. Farnesyl and geranylgeranyl transferase-I activities are present at all stages of P. falciparum intraerythrocytic development with maximum specific activity in the ring stage. Geranylgeranyl transferase-I specific activity is two times that of farnesyl transferase in the ring stage. Peptidomimetics and prenyl analogues of protein farnesyl transferase substrates were tested as in vitro inhibitors of partially purified P. falciparum prenyl transferase and of malaria parasite growth. The peptidomimetics were significantly more potent inhibitors than lipid substrate analogues of both the activity of Mono-Q purified enzyme and parasite growth in intraerythrocytic cultures. Exposure of the parasite to the peptidomimetic L-745,631 also showed significant inhibition of morphological development beyond the trophozoite stage. These studies suggest the potential of designing or identifying differential inhibitors of P. falciparum and mammalian prenyl transferases as an approach to novel malaria therapy.

Electrospun polymer nanofibers with entrapped magnetic nanoparticles (magnetic NP-NF) represent a novel scaffold substrate that can be functionalized for single-step isolation and activation of specific lymphocyte subsets. Using a surface-embedded T cell receptor ligand/trigger (anti-CD3 monoclonal antibody), we demonstrate, as proof of principle, the use of magnetic NP-NF to specifically isolate, enrich, and activate CD3+T cells from a heterogeneous cell mixture, leading to preferential expansion of CD8+CD3+T cells. The large surface area, adjustable antibody density, and embedded paramagnetic properties of the NP-NF permitted enhanced activation and expansion; its use represents a strategy that is amenable to an efficient selection process for adoptive cellular therapy as well as for the isolation of other cellular subsets for downstream translational applications. © 2012 American Chemical Society.

Dual-modal in vivo tumor imaging and photodynamic therapy using hexagonal NaYF(4):Yb,Er/NaGdF(4) core-shell upconverting nanoparticles combined with a photosensitizer, chlorin e6, is reported. Tumors can be clearly observed not only in the upconversion luminescence image but also in the magnetic resonance image. In vivo photodynamic therapy by systemic administration is demonstrated under 980 nm irradiation.

The anti-inflammatory effects of low-molecular weight chitosan oligosaccharides (LM-COS) prepared from high-molecular weight chitosan by enzymatic digestion were investigated against allergic reaction and allergic asthma in vivo and in vitro. Allergic asthma is an inflammatory disease of the airways associated with enhanced degranulation and cytokine generation. The LM-COS (

In the present study, the pig CMP-N-acetylneuraminic acid hydroxylase gene (pcmah), a key enzyme for the synthesis of NeuGc (N-glycolylneuraminic acid), was cloned from pig small intestine and characterized. The ORF (open reading frame) of pcmah was 1734 bp, encoding 577 amino acids and consisting of 14 exons. Organ expression pattern analysis reveals that pcmah mRNA is mainly expressed in pig rectum, tongue, spleen and colon tissues, being the most highly expressed in small intestine. In the ectopic expression of pcmah, when pig kidney PK15 cells and human vascular endothelial ECV304 cells were transfected with the cloned pcmah, the NeuGc contents of these transfectants were greater in comparison with vector transfectants used as controls. In addition, in the functional analysis of NeuGc, HSMC (human-serum-mediated cytotoxicity) was elevated in the ectopic NeuGc-expressing pcmah-transfected cells compared with controls. Moreover, binding of human IgM to the pcmah-transfected cells was significantly increased, whereas binding of IgG was slightly increased, indicating that the human IgM type was a major anti-NeuGc antibody. Furthermore, pcmah silencing by shRNA (short hairpin RNA) resulted in a decrease in NeuGc content and xenoantigenicity in PK15. From the results, it was concluded that the pcmah gene was capable of synthesizing the NeuGc acting as a xenoantigen in humans, confirming the NeuGc-mediated rejection response in pig–human xenotransplantation.

Alterations in the glycan chains of cell surface glycoconjugates are frequently involved biological processes such as cell-cell interaction, cell migration, differentiation and development. Cultured embryonic (E18) rat cortical neurons underwent apoptosis in response to camptothecin, and lectin histochemistry showed that binding to apoptotic neurons of FITC-conjugated Maackia amurensis agglutinin (MAA), which is specific for terminal alpha2,3-sialic acid residues, increased progressively with increasing concentrations of camptothecin. Analysis of the total proteins of apoptotic neurons by SDS-PAGE, and lectin blotting using HRP-labeled MAA, revealed that the expression of terminal alpha2,3-sialic acid residues on an unknown protein with an apparent molecular mass of 25.6 kDa also increased in apoptotic neurons. NP-HPLC analysis of the total cellular N-glycans of normal and apoptotic neurons demonstrated that the expression of structurally simpler biantennary types of N-glycans fell by 49% during apoptosis whereas the more branched triantennary types of N-glycans with terminal sialic acid residues increased by up to 59%. These results suggest that increased surface expression of alpha2,3-sialic acid residues and hyperglycosylation of N-glycans is a common feature of cellular responses to changes in cell physiology such as tumorigenesis and apoptosis.

This study was to investigate the antinociceptive effects of moxibustion in a complete Freund's adjuvant (CFA)-induced arthritic rat model, and the effects of moxibustion on immunohistochemical changes at the spinal cord level. Moxibustion was applied to the ipsilateral (right) Zusanli (ST36) acupoint to the lesion side for 9 days to CFA-induced arthritic rats. The stepping force was measured as a behavioral test, c-Fos immunohistochemistry, NO production and nNOS Western blots were examined to evaluate antinociceptive effects. Moxibustion at ST36 significantly improved the stepping force in the affected hind limb in CFA-induced arthritis. Moreover, moxibustion at ST36 suppressed the production of NO and the protein expression of c-Fos and nNOS induced by arthritis. These results suggest that moxibustion at ST36 has a potent antinociceptive effect in an arthritic rat model, and modulates neuronal excitability and endogenous NO production by suppressing c-Fos and nNOS protein expression.

Apoptosis may occur in early embryos where the execution of essential developmental events has failed, and gangliosides, sialic acid-conjugated glycosphingolipids, are proposed to regulate cell differentiation and growth. To evaluate the regulatory roles of ganglioside GM3 in early embryonic development, this study examined its expressional patterns in apoptotic cells during early embryonic development in mice. Pre-implanted embryos were obtained by in vitro fertilization, which were treated at the 4-cell stage with three the apoptosis inducers, actinomycin D, camptothecin and cycloheximide, for 15 h. All three inducers significantly increased the percentage of apoptotic cells, as measured using a TUNEL method, but remarkably reduced the total cell numbers. The numbers of morula and blastocyst stages were significantly decreased by treatment of the embryos with the three apoptosis inducers compared with the control, with a similar result also observed in the number of blastomeres. Staining of early embryos with Hoechst 33342 revealed a significant percentage of apoptotic nuclei. Prominent immunofluorescence microscopy revealed a significant difference in the ganglioside GM3 expression in apoptotic embryos compared with the control, and RT-PCR also demonstrated a dramatic increase in ganglioside GM3 synthase mRNA in the apoptotic embryos. These results suggest that ganglioside GM3 may be pathophysiologically implicated in the regulation of early embryonic development through an apoptotic mechanism.