ABSTRACT
Osteoarthritis (OA) is a progressive disease that causes pain, stiffness, and inflammation in the affected joints. Currently, there are no effective treatments for preventing the worst outcomes, such as synovitis or cartilage degradation. Sarcodia montagneana and Corbicula fluminea are common species found in the ocean or in freshwater areas. Their extracts are demonstrated to possess both antioxidative and anti-inflammatory functions. This study aimed to investigate the synergistic effects of the extracts of Sarcodia montagneana (SME) and Corbicula fluminea (FCE) on reducing local and systemic inflammation, as well as their efficacy in OA symptom relief. An in vitro monocytic LPS-treated THP-1 cell model and in vivo MIA-induced mouse OA model were applied, and the results showed that the combinatory usage of SME and FCE effectively suppressed IFN-γ and TNF-α production when THP-1 cells were treated with LPS. SME and FCE also significantly decreased the systemic TNF-α level and joint swelling and prevented the loss of proteoglycan in the cartilage within the joints of OA mice. The data shown here provide a potential solution for the treatment of osteoarthritis.
ABSTRACT
We investigated the influence of hydroxyl groups on the anti-quorum-sensing (anti-QS) and anti-biofilm activity of structurally similar cyclic dipeptides, namely cyclo(L-Pro-L-Tyr), cyclo(L-Hyp-L-Tyr), and cyclo(L-Pro-L-Phe), against Pseudomonas aeruginosa PAO1. Cyclo(L-Pro-L-Phe), lacking hydroxyl groups, displayed higher virulence factor inhibition and cytotoxicity, but showed less inhibitory ability in biofilm formation. Cyclo(L-Pro-L-Tyr) and cyclo(L-Hyp-L-Tyr) suppressed genes in both the las and rhl systems, whereas cyclo(L-Pro-L-Phe) mainly downregulated rhlI and pqsR expression. These cyclic dipeptides interacted with the QS-related protein LasR, with similar binding efficiency to the autoinducer 3OC12-HSL, except for cyclo(L-Pro-L-Phe) which had lower affinity. In addition, the introduction of hydroxyl groups significantly improved the self-assembly ability of these peptides. Both cyclo(L-Pro-L-Tyr) and cyclo(L-Hyp-L-Tyr) formed assembly particles at the highest tested concentration. The findings revealed the structure-function relationship of this kind of cyclic dipeptides and provided basis for our follow-up research in the design and modification of anti-QS compounds.
ABSTRACT
Bacterial infections are one of the major contributing factors to human mortality, which can cause secondary damage to the injured area, such as leading to inflammation, tissue death, and even personal death. Herein, we developed a novel cyclodextrin (CD)-modified amphiphilic microgel with a 3D network nanostructure that encapsulates hydrophilic indocyanine green (ICG) as a trigger for photothermal therapy (PTT) and hydrophobic N,N'-disubstituted-butyl-N,N'-dinitro-1,4-benzenediamine (BNN6) as a heat-sensitive nitric oxide (NO) donor (CD@I-B) to cope with bacteria-infected wound therapy. This biocompatible microgel showed excellent broad-spectrum antibacterial capability under near-infrared (NIR) laser irradiation, while the photothermal conversion process promotes the deswelling of the microgel and release of NO, which synergistically accelerates wound healing. The therapy strategy by synergizing NO delivery with PTT promoted the formation of neovascularization and collagen fiber as well as the elimination of inflammation cells, thus facilitating wound healing. Our study further demonstrates the fantastic opportunities of applying high-performance microgels to provide all-in-one sites for treating wound sterilization and healing.
Subject(s)
Microgels , Nitric Oxide , Humans , Photothermal Therapy , Nitric Oxide Donors , Wound Healing , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , InflammationABSTRACT
In this work, we illustrate a strategy for constructing heterochiral peptide architectures with distinct structural, mechanical and thermal characteristics. A series of nanotube structures based on diphenylalanine (FF) and its chiral derivatives were examined. Pronounced effects relating to heterochirality on mechanostability and thermal stability can be identified. The homochiral peptide FF and its enantiomer ff formed nanotubes with high thermal and mechanical stabilities (Young's modulus: 20.3 ± 5.9 GPa for FF and 21.2 ± 4.7 GPa for ff). In contrast, heterochiral nanotubes formed by Ff and fF manifest superstructures along the axial direction with differed thermal and mechanical strength (Young's modulus: 7.3 ± 2.4 GPa for Ff and 8.3 ± 2.1 GPa for fF). Combining their single-crystal XRD structure and in silico results, it was demonstrated that the spatial orientations of aromatic moieties were subtly changed by heterochirality of peptide building blocks, which led to intramolecular face-to-face interactions. As the result, both intermolecular axial and interchannel interactions in heterochiral nanotubes were weakened as reflected in the strikingly deteriorated mechanical and thermal stabilities. Conversely, two aromatic side chains of the homochiral peptides were staggered and formed interdigitated steric zippers, which served as strong glues that secured the robustness of nanotubes in both axial and radial orientation. Furthermore, the generality of the heterochiral-mediated stereochemical effects was demonstrated in other "FF class" dipeptides, including fluorinated Ff, FW and FL. Our results unequivocally revealed the relationship between amino acid chirality, peptide molecule packing, and physical stabilities of "FF class" dipeptide self-assembled materials and provide valuable molecular insights into chirality-mediated stereochemical interactions in determining the properties of peptide architectures.
Subject(s)
Nanotubes , Peptides , Peptides/chemistry , Dipeptides/chemistry , Phenylalanine/chemistry , Amino Acids/chemistry , Nanotubes/chemistry , StereoisomerismABSTRACT
Pseudomonas aeruginosa infections pose a huge threat to cystic fibrosis patients, as well as those suffering from immunodeficiency. Antimicrobial resistance, especially multi-drug resistance, due to its ability to aggregate the compact biofilm, makes it more inefficient to treat this pathogen with traditional antibiotics. Biofilm and quorum sensing (QS) have become the alternative targets for treating P. aeruginosa infections. Previously, a cyclic dipeptide cyclo(L-Trp-L-Ser) has been identified as a QS inhibitor of P. aeruginosa. On the other hand, some monosaccharides have been proved lectin-targeting behavior and to mediate biofilm formation and adhesion of P. aeruginosa. We constructed novel cyclic dipeptide-carbohydrate conjugates as a low molecular weight dual-functional QS inhibitor, which can not only enhance its anti-QS activity but also enable good anti-biofilm and anti-adhesion ability. The IC50 of galactosylated c(WS) on biofilm formation and glass adhesion was 1/6 and 1/4 of that of the unmodified cyclic dipeptide, respectively. And the ability to eliminate the preformed biofilm was increased 10-fold. Furthermore, the carbohydrate conjugates can increase the germicidal efficiency of clinical antibiotic azithromycin when used synergistically. Our results provide a novel scaffold for developing anti-virulence adjuvants when taken with clinical antibiotics.
Subject(s)
Pseudomonas Infections , Pseudomonas aeruginosa , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacterial Adhesion , Biofilms , Carbohydrates/therapeutic use , Dipeptides/pharmacology , Glycosylation , Humans , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/metabolism , Quorum Sensing , Virulence Factors/metabolismABSTRACT
Inflenza A viruses (IAVs) are highly transmissible and pathogenic Orthomyxoviruses, which have led to worldwide outbreaks and seasonal pandemics of acute respiratory diseases, causing serious threats to public health. Currently used anti-influenza drugs may cause neurological side effects, and they are increasingly less effective against mutant strains. To help prevent the spread of IAVs, in this work, we have developed quercetin-derived carbonized nanogels (CNGsQur) that display potent viral inhibitory, antioxidative, and anti-inflammatory activities. The antiviral CNGsQur were synthesized by mild carbonization of quercetin (Qur), which successfully preserved their antioxidative and anti-inflammatory properties while also contributed enhanced properties, such as water solubility, viral binding, and biocompatibility. Antiviral assays of co-treatment, pre-treatment, and post-treatment indicate that CNGsQur interacts with the virion, revealing that the major antiviral mechanism resulting in the inhibition of the virus is by their attachment on the cell surface. Among them, the selectivity index (SI) of CNGsQur270 (>857.1) clearly indicated its great potential for clinical application in IAVs inhibition, which was much higher than that of pristine quercetin (63.7) and other clinical drugs (4-81). Compared with quercetin at the same dose, the combined effects of viral inhibition, antioxidative and anti-inflammatory activities impart the superior therapeutic effects of CNGsQur270 aerosol inhalation in the treatment of IAVs infection, as evidenced by a mouse model. These CNGsQur effectively prevent the spread of IAVs and suppress virus-induced inflammation while also exhibiting good in vivo biocompatibility. CNGsQur shows much promise as a clinical therapeutic agent against infection by IVAs.
Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A virus , Animals , Anti-Inflammatory Agents/pharmacology , Antiviral Agents/pharmacology , Influenza A Virus, H1N1 Subtype/physiology , Mice , Quercetin/pharmacologyABSTRACT
The use of conventional fabrication methods rapidly developed the performance and notable enhancements of optoelectronic devices. However, it proved challenging to develop and demonstrate stable optoelectronic devices with biodegradability and biocompatibility properties towards sustainable development and extensive applications. This study incorporates a water-soluble Cr-phycoerythrin (Cr-PE) biomaterial to observe its optical and electronic properties effects on the pristine indium gallium zinc oxide (IGZO)-based photodetector. The fabricated photodetector demonstrates an extended absorption detection region, enhanced optoelectronic performance, and switchable function properties. The resulting photocurrent and responsivity of the IGZO/Cr-PE structure have increased by 5.7 and 7.1 times as compared to the pristine IGZO photodetector. It was also observed that the photodetector could operate in UV and UV-visible with enhanced optical properties by effectively adding the water-soluble Cr-PE. Also, the sensing region of IGZO photodetector becomes changeable. It exhibits switchable dual detection by alternatively dripping and removing the Cr-PE on the IGZO layer. Different measurement parameters such as detectivity, repeatability, and sensitivity are highlighted to effectively prove the advantage of including Cr-PE on the photodetector structure. This study contributes to understanding the potential functions in improving optoelectronic devices through an environmental-friendly method.
Subject(s)
Gallium , Indium , Biocompatible Materials , Gallium/chemistry , Indium/chemistry , Water , ZincABSTRACT
Having infected by Helicobacter pylori, the infection often leads to gastritis, gastric ulcer, or even gastric cancer. The disease is typically treated with antibiotics as they used to effectively inhibit or kill H. pylori, thus reducing the incidence of gastric adenoma and cancer to significant extent. H. pylori, however, has developed drug resistance to many clinically used antibiotics over the years, highlighting the crisis of antibiotic failure during the H. pylori treatment. We report here that the fucoidan from Sargassum hemiphyllum can significantly reduce the infection of H. pylori without developing to drug resistance. Fucoidan appears to be a strong anti-inflammation agent as manifested by the RAW264.7 cell model examination. Fucoidan can prohibit H. pylori adhesion to host cells, thereby reducing the infection rate by 60%, especially in post treatment in the AGS cell model assay. Mechanistically, fucoidan intervenes the adhesion of BabA and AlpA of H. pylori significantly lowering the total count of H. pylori and the level of IL-6 and TNF-α in vivo. These results all converge on the same fact that fucoidan is an effective agent in a position to protect the stomach from the H. pylori infection by reducing both the total count and induced inflammation.
Subject(s)
Antineoplastic Agents/therapeutic use , Helicobacter Infections/drug therapy , Polysaccharides/therapeutic use , Sargassum/chemistry , Animals , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cytokines/metabolism , Drug Evaluation, Preclinical , Helicobacter pylori/drug effects , Humans , Mice , Mice, Inbred BALB C , Polysaccharides/isolation & purification , Polysaccharides/pharmacology , RAW 264.7 Cells , Stomach/drug effects , Stomach/immunology , Stomach/metabolismABSTRACT
Atopic dermatitis (AD) is a T helper (Th) 2 cell-mediated allergic disease, which features increased number of immunocytes and level of Th2-associated cytokines. Fucoidan is well known a naturally occurring agent effectively ameliorating many AD symptoms. Though these alleviative effects are exhilarating, the mechanisms behind, however, are still rather limited. In this study, we report that fucoidan derived from Cladosiphon okamuranus (FT) inhibits nitric oxide (NO) production by exerting its anti-inflammatory ability. Topical application on animals show that FT promotes skin repair, reduces immunocyte proliferation, and decreases serum IgE level. In histological analysis, FT favorably reduces epidermal hyperplasia and eosinophilic infiltration. The pharmacodynamics mechanism of FT is determined by means of down-regulating AD-associated cytokines (IL-4, IL-5, IL-22, IL-33, and TSLP) and up-regulating TGF-ß1 level. Moreover, FT can regulate systemic immunity by enhancing tolerogenic dendritic cells (Tol-DCs) to activate regulatory T cells (Treg) differentiation and to decrease the population of Th22 and memory B cells. Overall, topical application of FT is able to enhance Treg secreting TGF-ß1 and to down-regulate Th2 cell-mediated immunity so that AD symptoms are significantly alleviated. Thereby, FT is an ideal drug candidate potentially replacing or complementing corticosteroids to be developed and used as a therapeutic agent to treat AD.
Subject(s)
Dermatitis, Atopic/drug therapy , Polysaccharides/administration & dosage , Polysaccharides/therapeutic use , Seaweed/chemistry , Administration, Topical , Animals , Anti-Ulcer Agents/administration & dosage , Anti-Ulcer Agents/therapeutic use , Cell Survival/drug effects , Dermatitis, Atopic/chemically induced , Dinitrochlorobenzene/toxicity , Drug Administration Schedule , Male , Memory B Cells/drug effects , Memory B Cells/physiology , Mice , Mice, Inbred BALB C , Nitric Oxide/metabolism , Polysaccharides/chemistry , RAW 264.7 Cells , T-Lymphocytes, Regulatory , Th2 Cells/drug effects , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolismABSTRACT
Atopic dermatitis (AD) is a long-term allergic skin disorder that occurs most frequently in children. Currently, the common treatment of AD is corticosteroids; however, the drugs cause serious side effects. Therefore, there are many patients who seek complementary and alternative treatments such as healthy food. We report that fucoidan from Cladosiphon okamuranus (COP) exhibit exceptional immuno-modulatory effects significantly improving atopic dermatitis (AD) at both in vitro and in vivo levels: First, we performed the P815 cell degranulation assay, of which the results revealed that COP possesses anti-degranulation activity suggesting COP is very conducive to relieving allergic reactions of AD. Next, we performed the animal model examination, of which AD was significantly improved, suggesting COP can focally and globally modulate the immune systems of animals. The systemic improvements were manifested clearly by decreased epidermal hyperplasia, reduced infiltration of eosinophils, and decreased expression of AD-associated cytokines. Notably, COP reduced epidermal hyperplasia by downregulating the expression of IL-22. COP displayed therapeutic effects, which is comparable to corticosteroids but lack corticosteroid side effects, such as weight loss in our animal study. COP is multitudinous immunomodulatory abilities to serve as a healthy food supplement at the current stage, not least beneficial to atopic dermatitis.
Subject(s)
Dermatitis, Atopic/drug therapy , Dermatitis, Atopic/immunology , Immunomodulation , Phaeophyceae/chemistry , Polysaccharides/therapeutic use , Administration, Oral , Animals , Cell Death/drug effects , Cell Degranulation/drug effects , Cytokines/blood , Cytokines/metabolism , Dermatitis, Atopic/blood , Dinitrochlorobenzene , Disease Models, Animal , Epidermis/drug effects , Epidermis/pathology , Histamine/metabolism , Immunoglobulin E/blood , Immunomodulation/drug effects , Interleukin-4/metabolism , Lymph Nodes/drug effects , Lymph Nodes/pathology , Male , Mast Cells/drug effects , Mast Cells/physiology , Mice, Inbred BALB C , Molecular Weight , Monosaccharides/analysis , Polysaccharides/administration & dosage , Polysaccharides/pharmacologyABSTRACT
Effective antiviral therapeutics are urgently required to fight severe acute respiratory syndrome (SARS) caused by a SARS coronavirus (SARS-CoV). Because polyphenol catechins could confer antioxidative, anti-inflammatory, antiviral, and antimicrobial activities, we assessed the therapeutic effects of catechins against SARS-CoV replication in Vero E6 cells, the preventive effect of catechins on CD25/CD69/CD94/CD8+ cytotoxic T lymphocytes-mediated adaptive immunity, and the protective effect on lipopolysaccharide-induced acute lung injury (ALI) in mice. We found that catechins containing 32.8% epigallocatechin gallate, 15.2% epicatechin gallate, 13.2 epicatechin, 10.8% epigallocatechin, 10.4% gallocatechin, and 4.4% catechin directly inhibited SARS-CoV replication at sub-micromolecular concentrations. Four-week catechins ingestion increased CD8+ T cell percentage, upregulated CD69+/CD25+/CD94-NKG2A/CD8+ T lymphocytes-mediated adaptive immunity, and increased type I cytokines release responding to ovalbumin/alum. Catechins significantly reduced lipopolysaccharide-induced cytokine storm and oxidative stress and ALI by inhibiting PI3K/AKT/mTOR signaling to upregulate Beclin-1/Atg5-Atg12/LC3-II-mediated autophagy mechanism. Pretreatment of autophagy inhibitor 3-Methyladenine reversed the inhibiting effects of catechins on the cytokines and oxidative stress levels and ALI. In conclusion, our data indicated that catechins directly inhibited SARS-CoV replication, potentiated the CD25/CD69/CD94/CD8+ T lymphocytes-mediated adaptive immunity and attenuated lipopolysaccharide-induced ALI and cytokine storm by PI3K/AKT/mTOR-signaling-mediated autophagy, which may be applied to prevent and/or treat SARS-CoV infection.
ABSTRACT
Despite the effectiveness of primary treatment modalities for cancer, the side effects of treatments, medication resistance, and the deterioration of cachexia after disease progression lead to poor prognosis. A supportive treatment modality to overcome these limitations would be considered a major breakthrough. Here, we used two different target drugs to demonstrate whether a nutraceutical formula (fish oil, Se yeast, and micronutrient-enriched nutrition; NuF) can interfere with cancer cachexia and improve drug efficacy. After Lewis lung cancer (LLC) tumor injection, the C57BL/6 mice were orally administered targeted therapy drugs Iressa and Sutent alone or combined with NuF for 27 days. Sutent administration effectively inhibited tumor size but increased the number of lung metastases in the long term. Sutent combined with NuF had no significant difference in tumor weight and metastasis compare with Sutent alone. However, NuF slightly attenuated metastases number in lung may via mesenchymal marker N-cadherin suppression. NuF otherwise increased epithelial-like marker E-cadherin expression and induce NO-mediated intrinsic apoptotic pathway in tumor cells, thereby strengthening the ability of the targeted therapy drug Iressa for inhibiting tumor progression. Our results demonstrate that NuF can promote the anticancer effect of lung cancer to targeted therapy, especially in Iressa, by inhibiting HIF-1α and epithelial-mesenchymal transition (EMT) and inducing the apoptosis of lung cancer cells. Furthermore, NuF attenuates cancer-related cachectic symptoms by inhibiting systemic oxidative stress.
Subject(s)
Carcinoma, Lewis Lung/diet therapy , Carcinoma, Lewis Lung/drug therapy , Chemotherapy, Adjuvant/methods , Fish Oils/pharmacology , Micronutrients/pharmacology , Selenium/pharmacology , Yeast, Dried/pharmacology , Administration, Oral , Animals , Apoptosis/drug effects , Cachexia/drug therapy , Cachexia/etiology , Carcinoma, Lewis Lung/complications , Cell Line, Tumor , Disease Models, Animal , Epithelial-Mesenchymal Transition/drug effects , Fish Oils/administration & dosage , Gefitinib/administration & dosage , Gefitinib/pharmacology , Inflammation/drug therapy , Male , Mice, Inbred C57BL , Micronutrients/administration & dosage , Neoplasm Metastasis/prevention & control , Oxidation-Reduction/drug effects , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/pharmacology , Selenium/administration & dosage , Sunitinib/administration & dosage , Sunitinib/pharmacology , Tumor Burden/drug effects , Yeast, Dried/administration & dosageABSTRACT
(1) Background: Radiotherapy (RT) is one of the major treatments for non-small cell lung cancer, but RT-associated toxicities usually impede its anticancer effect. Nutrient supplementation has been applied for cancer prevention or a complementary measure to anticancer therapy. Here, we explored the influence of total nutrition supplementation before and after cancer occurrence on the anticancer benefit and side effects of RT. (2) Methods: C57BL/6JNarl mice were inoculated with Lewis lung carcinoma cells and then treated with radiotherapy. TNuF, a total nutrition formula, was prescribed by oral gavage. In the preventive groups, TNuF supplementation started from seven days before tumor inoculation. In the complementary groups, TNuF supplementation began after tumor inoculation. (3) Results: TNuF successfully enhanced the anticancer effect of RT against primary tumor and lung metastasis. Additionally, the complementary supplement improved the high serum TNF-α level and the wasting of sartorius muscle in mice receiving RT. In histologic and molecular analysis, TNuF was observed to modulate EGFR, apoptosis, and VEGF and PD-1/PD-L1 pathways. Furthermore, the anticancer benefit of the preventive supplement was comparable to that of the complementary administration. (4) Conclusions: Our results demonstrated that the prescription of the TNuF total nutrition formula before and after cancer diagnosis attains similar benefits in testing subjects with typical anticancer RT. TNuF is also a potential sensitizer to anti-PD-1 immune therapy.
ABSTRACT
Though reactive flavin-N5/C4α-oxide intermediates can be spectroscopically profiled for some flavin-assisted enzymatic reactions, their exact chemical configurations are hardly visualized. Structural systems biology and stable isotopic labelling techniques were exploited to correct this stereotypical view. Three transition-like complexes, the α-ketoacid N5-FMNox complex (I), the FMNox -N5-aloxyl-C'α- -C4α+ zwitterion (II), and the FMN-N5-ethenol-N5-C4α-epoxide (III), were determined from mandelate oxidase (Hmo) or its mutant Y128F (monooxygenase) crystals soaked with monofluoropyruvate (a product mimic), establishing that N5 of FMNox an alternative reaction center can polarize to an ylide-like mesomer in the active site. In contrast, four distinct flavin-C4α-oxide adducts (IV-VII) from Y128F crystals soaked with selected substrates materialize C4α of FMN an intrinsic reaction center, witnessing oxidation, Baeyer-Villiger/peroxide-assisted decarboxylation, and epoxidation reactions. In conjunction with stopped-flow kinetics, the multifaceted flavin-dependent reaction continuum is physically dissected at molecular level for the first time.
Subject(s)
Amycolatopsis/enzymology , Bacterial Proteins/chemistry , Flavins/chemistry , Mixed Function Oxygenases/chemistry , Catalytic Domain , Oxidation-ReductionABSTRACT
Plant type III polyketide synthases produce diverse bioactive molecules with a great medicinal significance to human diseases. Here, we demonstrated versatility of a stilbene synthase (STS) from Pinus Sylvestris, which can accept various non-physiological substrates to form unnatural polyketide products. Three enzymes (4-coumarate CoA ligase, malonyl-CoA synthetase and engineered benzoate CoA ligase) along with synthetic chemistry was practiced to synthesize starter and extender substrates for STS. Of these, the crystal structures of benzoate CoA ligase (BadA) from Rhodopseudomonas palustris in an apo form or in complex with a 2-chloro-1,3-thiazole-5-carboxyl-AMP or 2-methylthiazole-5-carboxyl-AMP intermediate were determined at resolutions of 1.57 Å, 1.7 Å, and 2.13 Å, respectively, which reinforces its capacity in production of unusual CoA starters. STS exhibits broad substrate promiscuity effectively affording structurally diverse polyketide products. Seven novel products showed desired cytotoxicity against a panel of cancer cell lines (A549, HCT116, Cal27). With the treatment of two selected compounds, the cancer cells underwent cell apoptosis in a dose-dependent manner. The precursor-directed biosynthesis alongside structure-guided enzyme engineering greatly expands the pharmaceutical repertoire of lead compounds with promising/enhanced biological activities.
Subject(s)
Acyl Coenzyme A/metabolism , Acyltransferases/metabolism , Coenzyme A Ligases/metabolism , Rhodopseudomonas/enzymology , Acyl Coenzyme A/chemistry , Acyl Coenzyme A/genetics , Apoptosis , Biosynthetic Pathways , Catalytic Domain , Cell Line, Tumor , Cell Shape , Cell Survival , Crystallography, X-Ray , Humans , Models, Molecular , Mutation/genetics , Polyketides/chemistry , Polyketides/metabolismABSTRACT
The aims of this study were to investigate the antioxidant, hypolipidemic and hepatic protective effects of Phascolosoma esculenta polysaccharides (PEP). PEP was prepared from Phascolosoma esculenta by enzyme hydrolysis and its characterization was analyzed. The antioxidant activities of PEP were evaluated by the assays of scavenging 1,1-Diphenyl-2-picrylhydrazyl (DPPH), superoxide anion, hydroxyl radicals and chelating ferrous ion in vitro. It showed that PEP could scavenge radicals effectively and had favorable antioxidant activities. In the meantime, the hypolipidemic effect of PEP was investigated in vivo by using mice model fed with high-fat diet with or without PEP treatment. Compared with the hyperlipidemic mice without treatment, the serum levels of total cholesterol (TC) (30.1-35.7%, p < 0.01), triglyceride (TG) (24.5-50.8%, p < 0.01 or p < 0.05), low-density lipoprotein cholesterol (LDL-C) (49.6-56.8%, p < 0.01) and liver levels of TC (21.0-28.4%, p < 0.01), TG (23.8-37.0%, p < 0.01) decreased significantly, whereas serum high-density lipoprotein cholesterol (HDL-C) (47.7-59.9%, p < 0.01 or p < 0.05) increased significantly after treatment with different dosage of PEP (0.2, 0.4 and 0.8 g per kg body weight, respectively). In addition, superoxide dismutase (SOD) (10.2-22.2% and 18.8-26.9%, p < 0.05), glutathione peroxidase (GSH-Px) (11.9-15.4% and 26.6-30.4%, p < 0.05) activities in serum and liver enhanced markedly while aspartate aminotransferase (AST) (18.7-29.6% and 42.4-58.0%, p < 0.05), alanine transaminase (ALT) (42.7-46.0% and 31.2-42.2%, p < 0.05) activities, as well as the levels of malondialdehyde (MDA) (15.9-24.4% and 15.0-16.8%, p < 0.01 or p < 0.05) in serum and liver reduced markedly. Moreover, the histopathological observation of livers indicated that PEP could attenuate liver cell injury. The animal experimental results demonstrated that PEP exerted hypolipidemic and hepatoprotective roles in hyperlipidemic mice. In summary, our results above suggest that PEP might be a potential natural antioxidant and utilized as a therapeutic candidate for hyperlipidemia.
Subject(s)
Antioxidants/pharmacology , Chemical and Drug Induced Liver Injury/prevention & control , Hypolipidemic Agents/pharmacology , Polysaccharides/pharmacology , Protective Agents/pharmacology , Animals , Body Weight/drug effects , Diet, High-Fat , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Iron Chelating Agents/pharmacology , Lipids/blood , Male , Mice , Polysaccharides/chemistry , Polysaccharides/therapeutic useABSTRACT
Lung cancer and its related cachexia are the leading cause of cancer death in the world. In this study, we report the inhibitory effect of the combined therapy of Astragalus membranaceus and Angelica sinensis, on tumor growth and cachexia in tumor-bearing mice. Lewis lung carcinoma cells were inoculated into male C57BL/6 and CAnN.Cg-Foxn1nu nude mice. After tumor inoculation, mice were fed orally by the combination of AM and AS in different doses. In C57BL/6 mice, the combination of AM and AS significantly inhibited the growth of cancer tumor and prevented the loss of body weight and skeletal muscle. It also diminished the formation of free radicals and cytokines, stimulated the differentiation of NK and Tc cells, and rebalanced the ratios of Th/Tc cells, Th1/Th2 cytokines, and M1/M2 tumor-associated macrophages. The herbal combination also downregulated the expression of NFκΒ, STAT3, HIF-1α, and VEGF in tumors. In contrast, the findings were not observed in the nude mice. Therefore, the combination of AM and AS is confirmed to inhibit the progression of lung cancer, cancer cachexia, and cancer inflammation through the immunomodulatory function.
ABSTRACT
The Y128F single mutant of p-hydroxymandelate oxidase (Hmo) is capable of oxidizing mandelate to benzoate via a four-electron oxidative decarboxylation reaction. When benzoylformate (the product of the first two-electron oxidation) and hydrogen peroxide (an oxidant) were used as substrates the reaction did not proceed, suggesting that free hydrogen peroxide is not the committed oxidant in the second two-electron oxidation. How the flavin mononucleotide (FMN)-dependent four-electron oxidation reaction takes place remains elusive. Structural and biochemical explorations have shed new light on this issue. 15 high-resolution crystal structures of Hmo and its mutants liganded with or without a substrate reveal that oxidized FMN (FMNox) possesses a previously unknown electrophilic/nucleophilic duality. In the Y128F mutant the active-site perturbation ensemble facilitates the polarization of FMNox to a nucleophilic ylide, which is in a position to act on an α-ketoacid, forming an N5-acyl-FMNred dead-end adduct. In four-electron oxidation, an intramolecular disproportionation reaction via an N5-alkanol-FMNred C'α carbanion intermediate may account for the ThDP/PLP/NADPH-independent oxidative decarboxylation reaction. A synthetic 5-deaza-FMNox cofactor in combination with an α-hydroxyamide or α-ketoamide biochemically and structurally supports the proposed mechanism.
Subject(s)
Alcohol Oxidoreductases/chemistry , Flavin Mononucleotide/chemistry , Actinobacteria/enzymology , Alcohol Oxidoreductases/genetics , Amycolatopsis , Binding Sites , Cloning, Molecular , Escherichia coli/genetics , Kinetics , Mutation , Oxidation-Reduction , Substrate SpecificityABSTRACT
The chemical constituents in Trifolium repens L. were comprehensively studied by UPLC in this work, and a total number of 308 compounds were detected with 169 ones identified. The possible fragmentation pathways were proposed and fragmentation rules were summarized. On the basis of the concluded strategies, the characterized compounds could be classified into organic acids and their derivatives, alkaloids, amino acids, peptides, flavonoids, oligosaccharides, coumarins, and other types of compounds. This approach provided a rapid way for the identification of constituents in T. repens L., and even in other complex analytes. Among the separation and identification of the constituents, three compounds of great amount were isolated and characterized by NMR. The expression of iNOS and COX-2 in LPS-induced RAW 264.7 cells was suppressed by the pretreatment with three isolated constituents. The results implied they may potentially serve as a remedy for the therapy of inflammation. PRACTICAL APPLICATIONS: This work provided a rapid method for the identification of the complex analyte, which could be used in TCM, natural food and so on. The summarized fragmentation rule could be applied for the analysis of several types of compounds, such as organic acids and their derivatives, alkaloids, amino acids and peptides, flavonoids, oligosaccharides, coumarins, and so on. Most of natural plants contain these kinds of compounds, so these rules could have wide applications. Except the phytochemical investigation, T. repens L. displayed anti-inflammation activity according to the reported literature, and the three isolated constituents may potentially serve as a remedy for the therapy of inflammation referring to the result of this research.