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1.
Phytother Res ; 35(4): 2108-2118, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33205491

ABSTRACT

The biological activities of water-soluble components of edible mushroom Rubinoboletus ballouii (RB) were seldom reported. Polysaccharides of RB (RBP) were prepared and well-characterized using chemical analyses. The immunomodulatory properties of RBP were investigated using human monocyte-derived dendritic cells (moDC) in vitro, and cyclophosphamide (CTX)-induced immunosuppressive mouse model. Results showed that RBP was found to contain 80.6% (w/w) of neutral sugars including D-fucose, D-mannose, D-glucose and D-galactose (1.7:1.4:1.0:1.8), and 12.5% (w/w) of proteins, which composed of glutamine, threonine, serine, etc. RBP could promote the maturation of moDC and increase the secretion of IL-12p40, IL-10, and TNF-α. Furthermore, the stimulation of IL-12p40 production was inhibited by pretreatment with toll-like receptor (TLR)-4 blocker or NF-κB pathway blocker, suggesting that the activation of moDC by RBP was mediated through NF-κB pathway via TLR-4 receptor. On the other hand, in CTX-treated mice, RBP restored the loss of CD34bright CD45dim hematopoietic stem cells and increased IL-2 production in sera and splenocytes culture supernatant, as well as up-regulated the percentage of CD4+ T helper lymphocyte in mice splenocytes. These findings strongly suggested that RBP are the active ingredients of RB responsible for its immunostimulatory actions and deserved to be further investigated as cancer supplements.


Subject(s)
Basidiomycota/chemistry , NF-kappa B/metabolism , Polysaccharides/therapeutic use , Toll-Like Receptor 4/metabolism , Animals , Humans , Mice , Polysaccharides/pharmacology
2.
Mater Sci Eng C Mater Biol Appl ; 118: 111537, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33255090

ABSTRACT

Aseptic loosening and bacterial infections are the two main causes of failure for metallic implants used for joint replacement. A coating that is both bioactive and possesses antimicrobial properties may address such shortcomings and improve the performance of the implant. We have sought to study the properties of combining hydroxyapatite-based nanoparticles or coatings with baicalein, a plant-extracted molecule with both antibacterial and antioxidant properties. (B-type) carbonated hydroxyapatite nanoparticles prepared by a chemical wet method could subsequently adsorbed by soaking in a baicalein solution. The amount of adsorbed baicalein was determined to be 63 mg.g-1 by thermogravimetric measurements. In a second approach, baicalein was adsorbed on a biomimetic calcium-deficient hydroxyapatite planar coating (12 µm thick) deposited on Ti6Al4V alloy from an aqueous solution of calcium, phosphate, sodium and magnesium salts. Soaking of the hydroxyapatite coated on titanium alloy in a baicalein solution induced partial dissolution/remodeling of the upper surface of the coating. However, the observed remodeling of the surface was much more pronounced in the presence of a baicalein solution, compared to pure water. The presence of adsorbed baicalein on the HAp layer, although it could not be precisely quantified, was assessed by XPS and fluorescence analysis. Planar coatings exhibited significant antibacterial properties against Staphylococcus epidermidis. Baicalein-modified nanoparticles exhibited significant antioxidant properties. These results illustrate the potential of hydroxyapatite used as a carrier for natural biologically-active molecules and also discuss the challenges associated with their applications as antibacterial agents.


Subject(s)
Durapatite , Nanoparticles , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Coated Materials, Biocompatible/pharmacology , Flavanones , Surface Properties , Titanium
3.
Emerg Microbes Infect ; 9(1): 1628-1637, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32619386

ABSTRACT

Antimicrobial photodynamic therapy (aPDT) is an innovative approach to combat multi-drug resistant bacteria. It is known that cationic Zn(II) phthalocyanines (ZnPc) are effective in mediating aPDT against methicillin-resistant Staphylococcus aureus (MRSA). Here we used ZnPc-based photosensitizer named ZnPcE previously reported by our research group to evaluate its aPDT efficacy against broad spectrum of clinically relevant MRSAs. Remarkably, in vitro anti-MRSA activity was achieved using near-infrared (NIR, >610 nm) light with minimal bactericidal concentrations ranging <0.019-0.156 µM against the panel of MRSAs. ZnPcE was not only significantly (p < .05) more potent than methylene blue, which is a clinically approved photosensitizer but also demonstrated low cytotoxicity against human fibroblasts cell line (Hs-27) and human immortalized keratinocytes cell line (HaCaT). The toxicity was further evaluated on human 3-D skin constructs and found ZnPcE did not manifest in vivo skin irritation at ≤7.8 µM concentration. In the murine MRSA wound model, ZnPcE with PDT group demonstrated > 4 log10 CFU reduction and the value is significantly higher (p < .05) than all test groups except positive control. To conclude, results of present study provide a scientific basis for future clinical evaluation of ZnPcE-PDT on MRSA wound infection.


Subject(s)
Indoles/administration & dosage , Methicillin-Resistant Staphylococcus aureus/drug effects , Organometallic Compounds/administration & dosage , Photochemotherapy/methods , Photosensitizing Agents/administration & dosage , Staphylococcal Infections/drug therapy , Administration, Topical , Animals , Cell Line , Disease Models, Animal , Humans , Indoles/chemistry , Indoles/pharmacology , Isoindoles , Male , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Mice , Microbial Sensitivity Tests , Molecular Structure , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Zinc Compounds
4.
Biomedicines ; 8(6)2020 May 29.
Article in English | MEDLINE | ID: mdl-32485946

ABSTRACT

A series of cationic boron dipyrromethene (BODIPY) derivatives were synthesized and characterized with various spectroscopic methods. Having the ability to generate singlet oxygen upon irradiation, these compounds could potentially serve as photosensitizers for antimicrobial photodynamic therapy. Of the five BODIPYs being examined, the dicationic aza-BODIPY analogue (compound 5) demonstrated the highest potency against a broad spectrum of clinically relevant methicillin-resistant Staphylococcus aureus (MRSA), including four ATCC-type strains (ATCC 43300, ATCC BAA-42, ATCC BAA-43, and ATCC BAA-44), two strains carrying specific antibiotic resistance mechanisms [-AAC(6')-APH(2") and RN4220/pUL5054], and ten non-duplicate clinical strains from hospital- and community-associated MRSAs of the important clonal types ST239, ST30, and ST59, which have previously been documented to be prevalent in Hong Kong and its neighboring countries. The in vitro anti-MRSA activity of compound 5 was achieved upon irradiation with near-infrared light (>610 nm) with minimal bactericidal concentrations (MBCs) ranging from 12.5 to 25 µM against the whole panel of MRSAs, except the hospital-associated MRSAs for which the MBCs were in the range of 50-100 µM. Compound 5 was significantly (p < 0.05) more potent than methylene blue, which is a clinically approved photosensitizer, indicating that it is a promising antimicrobial agent that is worthy of further investigation.

5.
J Photochem Photobiol B ; 203: 111776, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31931388

ABSTRACT

Due to the emergence of antibiotic resistance, antimicrobial photodynamic therapy (aPDT) has recently been demonstrated as a promising alternative to antibiotics to treat wound infections caused by multidrug-resistant (MDR) pathogens. This study aimed to evaluate the bacterial killing efficiency of aPDT mediated by methylene blue (MB) loaded thermosensitive hydrogels against methicillin-resistant Staphylococcus aureus (MRSA). Box-Behnken Design method was employed to investigate the impacts of the polymer compositions, Poloxamer 407, Poloxamer 188 and Carbopol 934P, on the gelation temperature (Tsol-gel) and release rate of MB. The viscosity and in vitro bacterial killing efficiency of three selected formulations with Tsol-gel ranged 25-34 °C and MB release in 2 h (the incubation time used for aPDT experiment) ≥ 70%, were assessed. The viscosity was found to increase with increasing P407 content and increasing total gel concentration. In the in vitro aPDT experiment, all tested MB-hydrogels demonstrated >2.5 log10 colony forming unit (CFU) reduction against three clinical relevant MRSA strains. Interestingly, the bacterial reduction increased with decreasing amount of gel added (reduced MB concentration). This was possibly attributed to the increased viscosity at higher gel concentration reducing the diffusion rate of released MB towards bacterial cells leading to reduced aPDT efficiency. In summary, aPDT with the thermosensitive MB hydrogel formulations is a promising treatment strategy for wound infections.


Subject(s)
Anti-Infective Agents/chemistry , Hydrogels/chemistry , Methylene Blue/chemistry , Anti-Infective Agents/metabolism , Anti-Infective Agents/pharmacology , Drug Carriers/chemistry , Drug Liberation , Light , Methicillin-Resistant Staphylococcus aureus/drug effects , Methylene Blue/metabolism , Methylene Blue/pharmacology , Rheology , Temperature , Viscosity
6.
Article in English | MEDLINE | ID: mdl-31551932

ABSTRACT

Glucagon, a key hormone for glucose homeostasis, can exert functional crosstalk with somatotropic axis via modification of IGF-I expression. However, its effect on IGF-I regulation is highly variable in different studies and the mechanisms involved are largely unknown. Using grass carp as a model, the signal transduction and transcriptional mechanisms for IGF-I regulation by glucagon were examined in Cyprinid species. As a first step, the carp HNF1α, a liver-enriched transcription factor, was cloned and confirmed to be a single-copy gene expressed in the liver. In grass carp hepatocytes, glucagon treatment could elevate IGF-I, HNF1α, and CREB mRNA levels, induce CREB phosphorylation, and up-regulate HNF1α and CREB protein expression. The effects on IGF-I, HNF1α, and CREB gene expression were mediated by cAMP/PKA and PLC/IP3/PKC pathways with differential coupling with the MAPK and PI3K/Akt cascades. During the process, protein:protein interaction between HNF1α and CREB and recruitment of RNA Pol-II to IGF-I promoter also occurred with a rise in IGF-I primary transcript level. In parallel study to examine grass carp IGF-I promoter activity expressed in αT3 cells, similar pathways for post-receptor signaling were also confirmed in glucagon-induced IGF-I promoter activation and the trans-activating effect by glucagon was mediated by the binding sites for HNF1α and CREB located in the proximal region of IGF-I promoter. Our findings, as a whole, shed light on a previously undescribed mechanism for glucagon-induced IGF-I gene expression by increasing HNF1α and CREB production via functional crosstalk of post-receptor signaling. Probably, by protein:protein interaction between the two transcription factors and subsequent transactivation via their respective cis-acting elements in the IGF-I promoter, IGF-I gene transcription can be initiated by glucagon at the hepatic level.

7.
Front Immunol ; 10: 364, 2019.
Article in English | MEDLINE | ID: mdl-30886621

ABSTRACT

Interleukin (IL)-33 belongs to IL-1 cytokine family which is constitutively produced from the structural and lining cells including fibroblasts, endothelial cells, and epithelial cells of skin, gastrointestinal tract, and lungs that are exposed to the environment. Different from most cytokines that are actively secreted from cells, nuclear cytokine IL-33 is passively released during cell necrosis or when tissues are damaged, suggesting that it may function as an alarmin that alerts the immune system after endothelial or epithelial cell damage during infection, physical stress, or trauma. IL-33 plays important roles in type-2 innate immunity via activation of allergic inflammation-related eosinophils, basophils, mast cells, macrophages, and group 2 innate lymphoid cells (ILC2s) through its receptor ST2. In this review, we focus on the recent advances of the underlying intercellular and intracellular mechanisms by which IL-33 can regulate the allergic inflammation in various allergic diseases including allergic asthma and atopic dermatitis. The future pharmacological strategy and application of traditional Chinese medicines targeting the IL-33/ST2 axis for anti-inflammatory therapy of allergic diseases were also discussed.


Subject(s)
Hypersensitivity , Immunity, Innate , Interleukin-33/immunology , Humans , Hypersensitivity/immunology , Hypersensitivity/pathology , Hypersensitivity/therapy , Inflammation/immunology , Inflammation/pathology , Inflammation/therapy , Interleukin-1 Receptor-Like 1 Protein/immunology , Leukocytes/immunology , Leukocytes/pathology , Medicine, Chinese Traditional
8.
Article in English | MEDLINE | ID: mdl-30899246

ABSTRACT

In fish models, seasonal change in feeding is under the influence of water temperature. However, the effects of temperature on appetite control can vary among fish species and the mechanisms involved have not been fully characterized. Using goldfish (Carassius auratus) as a model, seasonal changes in feeding behavior and food intake were examined in cyprinid species. In our study, foraging activity and food consumption in goldfish were found to be reduced with positive correlation to the gradual drop in water temperature occurring during the transition from summer (28.4 ± 2.2°C) to winter (15.1 ± 2.6°C). In goldfish with a 4-week acclimation at 28°C, their foraging activity and food consumption were notably higher than their counterparts with similar acclimation at 15°C. When compared to the group at 28°C during summer, the attenuation in feeding responses at 15°C during the winter also occurred with parallel rises of leptin I and II mRNA levels in the liver. Meanwhile, a drop in orexin mRNA along with concurrent elevations of CCK, MCH, POMC, CART, and leptin receptor (LepR) transcript expression could be noted in brain areas involved in feeding control. In short-term study, goldfish acclimated at 28°C were exposed to 15°C for 24 h and the treatment was effective in reducing foraging activity and food intake. The opposite was true in reciprocal experiment with a rise in water temperature to 28°C for goldfish acclimated at 15°C. In parallel time-course study with lowering of water temperature from 28 to 15°C, short-term exposure (6-12 h) of goldfish to 15°C could also increase leptin I and II mRNA levels in the liver. Similar to our seasonality study, transcript level of orexin was reduced along with up-regulation of CCK, MCH, POMC, CART, and LepR gene expression in different brain areas. Our results, as a whole, suggest that temperature-driven regulation of leptin output from the liver in conjunction with parallel modulations of orexigenic/anorexigenic signals and leptin responsiveness in the brain may contribute to the seasonal changes of feeding behavior and food intake observed in goldfish.

9.
J Gen Virol ; 98(12): 3046-3059, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29106348

ABSTRACT

Compared to the enormous species diversity of bats, relatively few parvoviruses have been reported. We detected diverse and potentially novel parvoviruses from bats in Hong Kong and mainland China. Parvoviruses belonging to Amdoparvovirus, Bocaparvovirus and Dependoparvovirus were detected in alimentary, liver and spleen samples from 16 different chiropteran species of five families by PCR. Phylogenetic analysis of partial helicase sequences showed that they potentially belonged to 25 bocaparvovirus, three dependoparvovirus and one amdoparvovirus species. Nearly complete genome sequencing confirmed the existence of at least four novel bat bocaparvovirus species (Rp-BtBoV1 and Rp-BtBoV2 from Rhinolophus pusillus, Rs-BtBoV2 from Rhinolophus sinicus and Rol-BtBoV1 from Rousettus leschenaultii) and two novel bat dependoparvovirus species (Rp-BtAAV1 from Rhinolophus pusillus and Rs-BtAAV1 from Rhinolophus sinicus). Rs-BtBoV2 was closely related to Ungulate bocaparvovirus 5 with 93, 72.1 and 78.7 % amino acid identities in the NS1, NP1 and VP1/VP2 genes, respectively. The detection of bat bocaparvoviruses, including Rs-BtBoV2, closely related to porcine bocaparvoviruses, suggests recent interspecies transmission of bocaparvoviruses between bats and swine. Moreover, Rp-BtAAV1 and Rs-BtAAV1 were most closely related to human AAV1 with 48.7 and 57.5 % amino acid identities in the rep gene. The phylogenetic relationship between BtAAVs and other mammalian AAVs suggests bats as the ancestral origin of mammalian AAVs. Furthermore, parvoviruses of the same species were detected from multiple bat species or families, supporting the ability of bat parvoviruses to cross species barriers. The results extend our knowledge on the diversity of bat parvoviruses and the role of bats in parvovirus evolution and emergence in humans and animals.

10.
Molecules ; 21(4): 519, 2016 Apr 20.
Article in English | MEDLINE | ID: mdl-27104513

ABSTRACT

Atopic dermatitis (AD) is a common allergic skin disease, characterized by dryness, itchiness, thickening and inflammation of the skin. Infiltration of eosinophils into the dermal layer and presence of edema are typical characteristics in the skin biopsy of AD patients. Previous in vitro and clinical studies showed that the Pentaherbs formula (PHF) consisting of five traditional Chinese herbal medicines, Flos Lonicerae, Herba Menthae, Cortex Phellodendri, Cortex Moutan and Rhizoma Atractylodis at w/w ratio of 2:1:2:2:2 exhibited therapeutic potential in treating AD. In this study, an in vivo murine model with oxazolone (OXA)-mediated dermatitis was used to elucidate the efficacy of PHF. Active ingredients of PHF water extract were also identified and quantified, and their in vitro anti-inflammatory activities on pruritogenic cytokine IL-31- and alarmin IL-33-activated human eosinophils and dermal fibroblasts were evaluated. Ear swelling, epidermis thickening and eosinophils infiltration in epidermal and dermal layers, and the release of serum IL-12 of the murine OXA-mediated dermatitis were significantly reduced upon oral or topical treatment with PHF (all p < 0.05). Gallic acid, chlorogenic acid and berberine contents (w/w) in PHF were found to be 0.479%, 1.201% and 0.022%, respectively. Gallic acid and chlorogenic acid could suppress the release of pro-inflammatory cytokine IL-6 and chemokine CCL7 and CXCL8, respectively, in IL-31- and IL-33-treated eosinophils-dermal fibroblasts co-culture; while berberine could suppress the release of IL-6, CXCL8, CCL2 and CCL7 in the eosinophil culture and eosinophils-dermal fibroblasts co-culture (all p < 0.05). These findings suggest that PHF can ameliorate allergic inflammation and attenuate the activation of eosinophils.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Berberine/administration & dosage , Chlorogenic Acid/administration & dosage , Dermatitis, Atopic/drug therapy , Drugs, Chinese Herbal/chemistry , Gallic Acid/administration & dosage , Animals , Anti-Inflammatory Agents/pharmacology , Berberine/pharmacology , Cells, Cultured , Chemokines/metabolism , Chlorogenic Acid/pharmacology , Coculture Techniques , Dermatitis, Atopic/chemically induced , Dermatitis, Atopic/immunology , Disease Models, Animal , Eosinophils/cytology , Eosinophils/drug effects , Fibroblasts/cytology , Fibroblasts/drug effects , Gallic Acid/pharmacology , Humans , Interleukin-12/metabolism , Medicine, Chinese Traditional , Mice , Oxazolone/adverse effects
11.
J Pharm Pharmacol ; 67(1): 107-16, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25212982

ABSTRACT

OBJECTIVES: The aims of this study were to identify the active ingredients from Portulaca oleracea L. (PO) that could provide synergism with antibiotics against methicillin-resistant Staphylococcus aureus (MRSA) and their possible mechanisms of resistance inhibition. METHODS: High-speed counter-current chromatography (HSCCC) coupled with gas chromatography-mass spectrometry and a panel of laboratory MRSA strains were used for checkerboard and efflux inhibitory assays. KEY FINDINGS: Linoleic and oleic acids were identified from HSCCC fraction 18 of PO with synergistic antibacterial activity when combined with erythromycin against RN4220/pUL5054. Ethidium bromide efflux inhibitory studies revealed that linoleic and oleic acids may interfere the activity of MsrA pump. By comparing among a panel of linoleic and oleic acids analogues, unsaturated fatty acids in salt form with cis configuration and an increase in number of double bonds were found to further increase the antibacterial activity when used alone or in combination with antibiotics. CONCLUSION: This study reported for the first time that two active ingredients, namely linoleic and oleic acids, were identified from PO with synergistic antibacterial activity when combined with erythromycin against MRSA RN4220/pUL5054 and possibly act by inhibiting the efflux pumps of the bacteria cells.


Subject(s)
Anti-Bacterial Agents/pharmacology , Erythromycin/pharmacology , Linoleic Acid/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Oleic Acid/pharmacology , Portulaca , Ciprofloxacin/pharmacology , Drug Synergism , Drug Therapy, Combination , Gas Chromatography-Mass Spectrometry , Linoleic Acid/chemistry , Microbial Sensitivity Tests , Oleic Acid/chemistry , Plant Extracts/chemistry
12.
Fetal Diagn Ther ; 35(4): 280-8, 2014.
Article in English | MEDLINE | ID: mdl-24802980

ABSTRACT

INTRODUCTION: Cytokine imbalance has been implicated in placental-related pathologies, i.e. recurrent miscarriage and pre-eclampsia. Such conditions are more prevalent in multiple pregnancies. Twin-to-twin transfusion syndrome (TTTS) is associated with asymmetric placental blood flow and intra-cardiac pressures. We hypothesised that cytokine expression may be aberrant in this condition and that fetoscopic laser ablation (FLA) may cause local cytokine release. MATERIAL AND METHODS: A prospective cohort of monochorionic, diamniotic twins with TTTS (n = 23) was studied. Circulating T helper cell type 1 (TH1)/TH2 maternal cytokines and cytokine-related and angiogenic factors were measured in plasma and amniotic fluid before and after FLA by human FASTQuant or ELISA. Basal comparisons were made with uncomplicated monochorionic and dichorionic (DC) twins. RESULTS: Median maternal plasma platelet-derived growth factor-BB was highest in uncomplicated DC twins (p = 0.049), whereas tissue inhibitor of metalloproteinases (TIMP)-1 was highest in TTTS twins (p = 0.003). In TTTS amniotic fluid, interleukin (IL)-6, IL-1ß, tumour necrosis factor-α, IL-10, IL-4, IL-8, interferon-γ, TIMP-1 and intercellular adhesion molecule-1 were significantly higher than maternal plasma concentrations. There were no significant differences in plasma or amniotic fluid cytokines after FLA, with the exception of amniotic fluid keratinocyte growth factor, which was significantly reduced. DISCUSSION: TTTS is associated with minimal changes in cytokine levels when compared to uncomplicated twins, although the majority of cytokine levels were higher in amniotic fluid than maternal blood. It does not appear that FLA evokes a significant change in cytokines.


Subject(s)
Amniotic Fluid/metabolism , Cytokines/metabolism , Fetofetal Transfusion/surgery , Cytokines/blood , Female , Fetofetal Transfusion/metabolism , Fetoscopy , Humans , Laser Therapy , Pregnancy , Pregnancy Outcome , Pregnancy, Twin , Prospective Studies
13.
Nutr Cancer ; 65(5): 765-74, 2013.
Article in English | MEDLINE | ID: mdl-23859044

ABSTRACT

Medicinal mushrooms have been traditionally used as food nutrient supplements in China for thousands of years. The present study aimed to evaluate the immunomodulatory activities of Ganoderma sinense (GS), an allied species of G. lucidum, using human peripheral blood mononuclear cells (PBMC). Our results showed that the polysaccharide-enriched fraction of GS hot water extract (400 µg/ml) exhibited significant stimulatory effects on PBMC proliferation. When the fruiting bodies of GS were divided into pileus and stipe parts and were separately extracted, the GS stipe polysaccharide-enriched fraction (50-400 µg/ml) showed concentration-dependent immunostimulating effects in PBMC. The productions of tumor necrosis factor-α, interleukin (IL)-10, and transforming growth factor -ß were significantly enhanced by this fraction. In addition, the proportion of CD14(+) monocyte subpopulation within the PBMC was specifically increased. The IL-10 and IL-12 productions in monocyte-derived dendritic cells were significantly enhanced by GS stipe fraction. The composition of monosaccharides of this fraction was determined by ultra performance liquid chromatography and ion exchange chromatography. Our study demonstrated for the first time the immunostimulatory effects of GS stipe polysaccharide-enriched fraction on PBMC and dendritic cells. The findings revealed the potential use of GS (especially including the stipes of fruiting bodies) as adjuvant nutrient supplements for patients, who are receiving immunosuppressive chemotherapies.


Subject(s)
Ganoderma/chemistry , Leukocytes, Mononuclear/drug effects , Polysaccharides/pharmacology , Amino Acids/analysis , Cell Proliferation/drug effects , China , Dendritic Cells/drug effects , Dendritic Cells/immunology , Humans , Interleukin-10/immunology , Interleukin-12/immunology , Leukocytes, Mononuclear/immunology , Polysaccharides/isolation & purification , Transforming Growth Factor beta/immunology , Tumor Necrosis Factor-alpha/immunology
14.
Phytomedicine ; 20(7): 611-4, 2013 May 15.
Article in English | MEDLINE | ID: mdl-23541215

ABSTRACT

Increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) worldwide with limited therapeutic options is a growing public health concern. Natural products have been shown to possess antibacterial actions against MRSA. Flavonoids from natural products have been shown to possess antibacterial actions against MRSA by antagonizing its resistance mechanisms. Diosmin and diosmetin are natural flavonoids found in a variety of citrus fruits. The aim of this study was to investigate whether diosmin and diosmetin could inhibit the growth of MRSA and the in vitro enzymatic activity of a newly discovered MRSA drug target, pyruvate kinase (PK). By using a panel of MRSA strains with known resistant mechanisms, neither diosmin nor diosmetin was shown to possess direct antibacterial activities against all tested MRSA strains. However, in checkerboard assay, we found that diosmetin together with erythromycin, could synergistically inhibit the growth of ABC-pump overexpressed MRSA-RN4220/pUL5054, and time kill assay also showed that the antibacterial activities of diosmetin with erythromycin were bactericidal. Diosmetin was further shown to significantly suppress the MRSA PK activities in a dose dependent manner. In conclusion, the inhibition of MRSA PK by diosmetin could lead to a deficiency of ATP and affect the bacterial efflux pump which might contribute to the antibacterial actions of diosmetin against MRSA.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Anti-Bacterial Agents/pharmacology , Erythromycin/pharmacology , Flavonoids/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Pyruvate Kinase/antagonists & inhibitors , Adenosine Triphosphate/metabolism , Diosmin/pharmacology , Dose-Response Relationship, Drug , Drug Synergism , Methicillin-Resistant Staphylococcus aureus/metabolism , Microbial Sensitivity Tests
15.
Molecules ; 18(3): 2483-500, 2013 Feb 25.
Article in English | MEDLINE | ID: mdl-23439564

ABSTRACT

Pentaherb formula (PHF) has been proven to improve the quality of life of children with atopic dermatitis without side effects. The aim of this study was to elucidate the potential anti-inflammatory and anti-allergic activities of PHF, Moutan Cortex (Danpi/DP) and gallic acid (GA) using human basophils (KU812 cells), which are crucial effector cells in allergic inflammation. PHF, DP and GA could significantly suppress the expression of allergic inflammatory cytokine IL-33-upregulated intercellular adhesion molecule (ICAM)-1, and the release of chemokines CCL2, CCL5, CXCL8 and inflammatory cytokine IL-6 from KU812 cells (all p < 0.05). With the combined use of dexamethasone (0.01 µg/mL) and GA (10 µg/mL), the suppression of ICAM-1 expression and CCL5 and IL-6 release of IL-33-activated KU812 cells were significantly greater than the use of GA alone (all p < 0.05). The suppression of the IL-33-induced activation of intracellular signalling molecules p38 mitogen activated protein kinase, nuclear factor-kB and c-Jun amino-terminal kinase in GA-treated KU812 cells could be the underlying mechanism for the suppression on ICAM-1, chemokines and cytokines. The combined use of dexamethasone with the natural products PHF or DP or GA might therefore enhance the development of a novel therapeutic modality for allergic inflammatory diseases with high potency and fewer side effects.


Subject(s)
Anti-Allergic Agents/pharmacology , Anti-Inflammatory Agents/pharmacology , Drugs, Chinese Herbal/pharmacology , Gallic Acid/pharmacology , Basophils/drug effects , Basophils/metabolism , Cell Adhesion Molecules/metabolism , Cell Line , Chemokines/biosynthesis , Dexamethasone/pharmacology , Humans , Interleukin-33 , Interleukin-6/biosynthesis , Interleukins/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Paeonia , Phosphorylation/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
16.
Eur J Med Chem ; 59: 243-52, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23231968

ABSTRACT

Bigelovin is a sesquiterpene lactone isolated from the plant Inula helianthus-aquatica which was traditionally used in cancer treatment in Yunnan, China. The potent apoptotic activities of bigelovin in human leukemia U937 cells were shown in our previous study. The present study investigated the anti-angiogenic and immunomodulatory effects of bigelovin using transgenic zebrafish Tg(fli1a:EGFP)y1 with fluorescent blood vessels and human peripheral blood mononuclear cells (PBMCs), respectively. Furthermore, the inhibitory activities of bigelovin on the human endothelial cell adhesion molecules (CAMs) were also examined. Our results showed that the growth of subintestinal vessels of the bigelovin-treated zebrafish embryos was significantly inhibited and the gene expressions in angiogenesis signaling pathways (e.g. Ang2 and Tie2) of the zebrafish were down-regulated after bigelovin treatment. Besides, the proliferation and Th1 cytokines productions (e.g. IFN-γ, IL-2 and IL-12) were suppressed in bigelovin-treated PBMCs. On the other hand, bigelovin was shown to significantly inhibit the human monocyte adhesion to human endothelial cells and the gene expressions of inflammation-related CAMs (e.g. ICAM-1, VCAM-1 and E-selectin) were significantly down-regulated in bigelovin-treated human endothelial cells. In summary, our data provide the first evidence that bigelovin possesses anti-angiogenic and immunomodulatory activities, suggesting bigelovin may exert multi-target functions against cancer in animal models.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Helianthus/chemistry , Immunologic Factors/chemistry , Immunologic Factors/pharmacology , Lactones/pharmacology , Neovascularization, Physiologic/drug effects , Plant Extracts/pharmacology , Sesquiterpenes/pharmacology , Animals , Animals, Genetically Modified , China , Embryo, Nonmammalian/drug effects , Gene Expression Regulation/drug effects , Humans , Lactones/chemistry , Lactones/isolation & purification , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification , U937 Cells , Zebrafish
17.
Acta Obstet Gynecol Scand ; 91(10): 1206-11, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22862673

ABSTRACT

OBJECTIVE: To investigate the effects of chorionicity and severe twin to twin transfusion (TTTS) on maternal circulating cell-free messenger RNA (cf-mRNA). DESIGN: Prospective cohort study. SETTING: A UK tertiary referral Fetal Medicine Center. POPULATION: All monochorionic (MC) twins complicated by severe TTTS (n= 23) and a cohort of uncomplicated dichorionic (DC) (n= 10) and MC (n= 7) pregnancies, between October 2006 and December 2007. METHODS: Maternal cf-mRNA encoding glyceraldehyde 3-phosphate dehydrogenase (GAPDH), vascular endothelial growth factor receptor 1(VEGFR-1(Flt-1)), vascular endothelial growth factor A (VEGF-A), Endoglin, placental growth factor (PlGF), tyrosine kinase with immunoglobulin-like and EGF-like domains 1 (Tie-1), angiopoietin 1 (Ang-1) and angiopoietin 2 (Ang-2) were measured by a quantitative two-step real-time PCR assay after extraction from maternal plasma. RESULTS: The amounts of cf-mRNA detectable are reported for uncomplicated DC, MC and TTTS pregnancies, respectively: GAPDH - 80, 100 and 96%; VEGFR-1 - 10, 0 and 26%; VEGF-A- 80, 71 and 96%; Endoglin-70, 71 and 91%; PlGF-70, 57, 26%; Tie-1 0, 43, 0%; Ang-1 71, 50 and 60% and Ang-2 83, 50 and 89%. There was a significant difference in VEGF-A (medians DC -337.3, MC - 390.8, TTTS - 618.6 copies/mL plasma p= 0.024), Endoglin (medians DC-14.49, MC-1171, TTTS - 2896 copies/mL plasma p= 0.027) and Ang-2 (medians DC-13.66, MC-8.49, TTTS 44.80 copies/mL plasma p= 0.007). CONCLUSION: Maternal cf-mRNA could be reliably detected for GAPDH, PlGF, VEGF-A, Endoglin, Ang-1 and Ang-2 in twin pregnancies and a significant difference was demonstrated in VEGF-A, Endoglin and Ang-2 between uncomplicated twins and MC twin pregnancies complicated by TTTS. If such alterations in maternal cf-mRNA precede the onset of clinically apparent disease, this may be used as an adjuvant blood test to complement ultrasound screening.


Subject(s)
Cell-Free System , Chorion , Fetofetal Transfusion/blood , RNA, Messenger/blood , Adult , Angiopoietin-2/blood , Antigens, CD/blood , Biomarkers/blood , Case-Control Studies , Cohort Studies , Endoglin , Female , Fetofetal Transfusion/diagnosis , Fetofetal Transfusion/genetics , Humans , Infant, Newborn , Pregnancy , Prospective Studies , Real-Time Polymerase Chain Reaction , Receptors, Cell Surface/blood , Severity of Illness Index , Twins, Monozygotic , Vascular Endothelial Growth Factor A/blood
18.
Phytother Res ; 26(6): 915-25, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22105892

ABSTRACT

The use of health supplements derived from medicinal herbs as self-medication for the relief of respiratory tract pathology symptoms is increasing in Chinese communities as air pollution is worsening. Twelve herbs from two formulae of our previous studies were evaluated for their anti-inflammatory, immunomodulatory and bronchorelaxant activities in this study. Among the extracts tested, those of Herba Schizonepetae and Radix Glycyrrhizae showed significant inhibitory effects on LPS-induced nitric oxide production (p < 0.05) in mouse macrophage RAW264.7 cells, suggesting their anti-inflammatory activities. Radix Scutellariae and Radix Glycyrrhizae extracts showed significant inhibitory effects on phytohaemagglutinin-induced proliferation in human peripheral blood mononuclear cells (p < 0.05). These extracts also showed inhibition of TNF-α, IFN-γ and IL-10 production. For the bronchorelaxant assay, Rhizoma Cynanchi Stauntonii and Radix Glycyrrhizae extracts showed potent attenuation of the acetylcholine- and carbachol-induced contractions in rat trachea (p < 0.05), implying their relaxant activities. In conclusion, Herba Schizonepetae, Radix Glycyrrhizae, Radix Scutellariae and Rhizoma Cynanchi Stauntonii extracts were demonstrated to exert anti-inflammatory, immunomodulatory and bronchorelaxant activities, which may help to ameliorate the symptoms of respiratory tract pathologies. The findings have thus provided some scientific evidence on the efficacy and mechanisms of action of these herbs, which are useful for the further development of clinical applications.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Bronchodilator Agents/pharmacology , Drugs, Chinese Herbal/pharmacology , Plant Extracts/pharmacology , Acetylcholine/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Bronchodilator Agents/chemistry , Carbachol/pharmacology , Cell Line, Tumor , Cell Proliferation , Cell Survival , Dinoprostone/metabolism , Drug Evaluation, Preclinical , Drugs, Chinese Herbal/chemistry , Glycyrrhiza/chemistry , Humans , Immunologic Factors/chemistry , Immunologic Factors/pharmacology , Interferon-alpha/immunology , Interleukin-10/immunology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/adverse effects , Male , Mice , Muscle Contraction , Muscle, Smooth/drug effects , Muscle, Smooth/metabolism , Nitric Oxide/chemistry , Parasympatholytics/chemistry , Parasympatholytics/pharmacology , Phytohemagglutinins/immunology , Phytohemagglutinins/pharmacology , Plant Extracts/chemistry , Rats , Rats, Sprague-Dawley , Scutellaria baicalensis/chemistry , Trachea/drug effects , Trachea/metabolism , Tumor Necrosis Factor-alpha
19.
J Ethnopharmacol ; 137(1): 767-73, 2011 Sep 01.
Article in English | MEDLINE | ID: mdl-21782012

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Baicalein, the active constituent derived from Scutellaria baicalensis Georgi., has previously been shown to significantly restore the effectiveness of ß-lactam antibiotics and tetracycline against methicillin-resistant Staphylococcus aureus (MRSA). With multiple therapeutic benefits, the antibacterial actions of baicalein may also be involved in overcoming other bacterial resistance mechanisms. The aim of the present study was to further investigate antibacterial activities of baicalein in association with various antibiotics against selected Staphylococcus aureus strains with known specific drug resistance mechanisms. MATERIAL AND METHODS: A panel of clinical MRSA strains was used for further confirmation of the antibacterial activities of baicalein. The effect of baicalein on inhibiting the enzymatic activity of a newly discovered MRSA-specific pyruvate kinase (PK), which is essential for Staphylococcus aureus growth and survival was also examined. RESULTS: In the checkerboard dilution test and time-kill assay, baicalein at 16 µg/ml could synergistically restore the antibacterial actions of ciprofloxacin against the NorA efflux pump overexpressed SA-1199B, but not with the poor NorA substrate, pefloxacin. Moreover, synergistic effects were observed when baicalein was combined with ciprofloxacin against 12 out of 20 clinical ciprofloxacin resistant strains. For MRSA PK studies, baicalein alone could inhibit the enzymatic activity of MRSA PK in a dose-dependent manner. CONCLUSION: Our results demonstrated that baicalein could significantly reverse the ciprofloxacin resistance of MRSA possibly by inhibiting the NorA efflux pump in vitro. The inhibition of MRSA PK by baicalein could lead to a deficiency of ATP which might further contribute to the antibacterial actions of baicalein against MRSA.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Ciprofloxacin/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Enzyme Inhibitors/pharmacology , Flavanones/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Multidrug Resistance-Associated Proteins/metabolism , Pyruvate Kinase/antagonists & inhibitors , Bacterial Proteins/genetics , Dose-Response Relationship, Drug , Drug Synergism , Drug Therapy, Combination , Methicillin-Resistant Staphylococcus aureus/enzymology , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/growth & development , Microbial Sensitivity Tests , Multidrug Resistance-Associated Proteins/genetics , Pyruvate Kinase/metabolism , Time Factors , Up-Regulation
20.
Int J Biol Macromol ; 47(3): 342-7, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20609432

ABSTRACT

Several curcuminoids and sesquiterpenoids isolated from Curcuma longa (CL) have been shown to have many pharmacological activities. In the present study, the immunomodulatory activities of the polar fractions of CL hot water extracts were investigated using human peripheral blood mononuclear cells (PBMC). Our results showed that the high polarity fraction of the hot water extract exhibited stimulatory effects on PBMC proliferation as shown in [methyl-(3)H]-thymidine incorporation assay. In an attempt to isolate the active components responsible for the activities, further partition with ethyl acetate, n-butanol and ethanol, progressively were performed. The cytokine productions (TGF-beta, TNF-alpha, GM-CSF, IL-1alpha, IL-5, IL-6, IL-8, IL-10, IL-13, etc.) have been modulated by a polysaccharide-enriched fraction as shown in ELISA and cytokine protein array. The proportion of CD14 positive stained PBMC was increased by such fraction. The composition of monosaccharide of the active fraction has been determined by GC-MS and gel permeation chromatography. The immunostimulatory effects of C. longa polysaccharides on PBMC were shown for the first time. The findings revealed the potential use of C. longa crude extract (containing curcuminoids and polysaccharides) as an adjuvant supplement for cancer patients, whose immune activities were suppressed during chemotherapies.


Subject(s)
Adjuvants, Immunologic/isolation & purification , Adjuvants, Immunologic/pharmacology , Curcuma/chemistry , Polysaccharides/immunology , Polysaccharides/isolation & purification , Adjuvants, Immunologic/chemistry , Antigens, CD/metabolism , Biological Assay , Cell Proliferation/drug effects , Chromatography, Gel , Cytokines/biosynthesis , Gas Chromatography-Mass Spectrometry , Gene Expression Regulation/immunology , Humans , Polysaccharides/chemistry , T-Lymphocyte Subsets/cytology , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism
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