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1.
Int J Biol Macromol ; 271(Pt 1): 132360, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38810432

RESUMO

Injectable adhesive hydrogels combining rapid gelling with robust adhesion to wet tissues are highly required for fast hemostasis in surgical and major trauma scenarios. Inspired by the cross-linking mechanism of mussel adhesion proteins, we developed a bionic double-crosslinked (BDC) hydrogel of poly (γ-glutamic acid) (PGA)/poly (N-(2-hydroxyethyl) acrylamide) (PHEA) fabricated through a combination of photo-initiated radical polymerization and hydrogen bonding cross-linking. The BDC hydrogel exhibited an ultrafast gelling process within 1 s. Its maximum adhesion strength to wet porcine skin reached 254.5 kPa (9 times higher than that of cyanoacrylate (CA) glue) and could withstand an ultrahigh burst pressure of 626.4 mmHg (24 times higher than that of CA glue). Notably, the BDC hydrogel could stop bleeding within 10 s from a rat liver incision 10 mm long and 5 mm deep. The wound treated with the BDC hydrogel healed faster than the control groups, underlining the potential for emergency rescue and wound care scenarios.


Assuntos
Hidrogéis , Ácido Poliglutâmico , Ácido Poliglutâmico/química , Ácido Poliglutâmico/análogos & derivados , Animais , Hidrogéis/química , Ratos , Pressão , Reagentes de Ligações Cruzadas/química , Cicatrização/efeitos dos fármacos , Suínos , Acrilamidas/química
2.
Biomater Sci ; 11(24): 7845-7855, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37901969

RESUMO

Massive bleeding and wound infection due to severe traumas pose a huge threat to the life and health of sufferers; therefore, it is of clinical importance to fabricate adhesives with rapid hemostatic and superior antibacterial capabilities. However, the weak wet adhesion and insufficient function of existing bioadhesives limits their practical application. In this study, a sandcastle worm protein inspired polyelectrolyte self-coacervate adhesive of poly-γ-glutamic acid (PGA) and lysozyme (LZM) was developed. The adhesive exhibited strong underwater adhesion to various surfaces (>250 kPa for solid plates and >50 kPa for soft tissues) and maintained a 80 kPa even when soaked in water for 7 days. Rat liver and tail defect bleeding models revealed that the hemostatic efficiency was superior to that of commercial samples. The in vitro antimicrobial tests showed that the bacterial inhibition to Staphylococcus aureus and Escherichia coli reached almost 100%. Additionally, the infected wound regeneration model demonstrated that the healing rate of the adhesive group was about 100% within 15 days, which was greater than that of the control group. In vitro and in vivo experiments proved that this facilely prepared adhesive will be a promising material to fulfil the integration functions for rapid wound closure and facilitating wound healing.


Assuntos
Adesivos , Hemostáticos , Ratos , Animais , Adesivos/farmacologia , Biomimética , Cicatrização , Hemostasia , Hemostáticos/farmacologia , Escherichia coli , Aderências Teciduais , Hemorragia , Hidrogéis/farmacologia , Antibacterianos/farmacologia
3.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37721785

RESUMO

The purpose of this study was to investigate whether prolactin (PRL) regulates the proliferation of pigeon crop epithelium through the Hippo signaling pathway during the breeding cycle. Twenty-four pairs of adult pigeons were allotted to four groups by different breeding stages, and their crops and serum were sampled. Eighteen pairs of young pigeons were selected and divided into three groups for the injection experiments. The results showed that the serum PRL content and crop epithelial thickness of pigeons increased significantly at day 17 of incubation (I17) and day 1 of chick-rearing (R1). In males, the mRNA levels of yes-associated transcriptional regulator (YAP) and snail family transcriptional repressor 2 (SNAI2) were peaked at I17, and the gene levels of large tumor suppressor kinase 1 (LATS1), serine/threonine kinase 3 (STK3), TEA domain transcription factor 3 (TEAD3), connective tissue growth factor (CTGF), MYC proto-oncogene (c-Myc) and SRY-box transcription factor 2 (SOX2) reached the maximum value at R1. In females, the gene expression of YAP, STK3, TEAD3, and SOX2 reached the greatest level at I17, the expression profile of SAV1, CTGF, and c-Myc were maximized at R1. In males, the protein levels of LATS1 and YAP were maximized at R1 and the CTGF expression was upregulated at I17. In females, LATS1, YAP, and CTGF reached a maximum value at I17, and the expression level of phosphorylated YAP was minimized at I17 in males and females. Subcutaneous injection of prolactin (injected for 6 d, 10 µg per kg body weight every day) on the left crop of pigeons can promote the proliferation of crop epithelium by increasing the CTGF level and reducing the phosphorylation level of YAP. YAP-TEAD inhibitor verteporfin (injection for 6 d, 2.5 mg per kg body weight every day) can inhibit the proliferation of crop epithelium induced by prolactin by inhibiting YAP and CTGF expression. In conclusion, PRL can participate in crop cell proliferation of pigeons by promoting the expression of YAP and CTGF in Hippo pathway.


This study evaluated whether prolactin (PRL) regulates the proliferation of pigeon crops through Hippo signaling pathway during the breeding cycle. Twenty-four pairs of adult pigeons were allotted to four groups by different breeding stages, and their crops and serum were sampled. Eighteen pairs of young pigeons were selected and divided into three groups for the injection experiments. The crop epithelial thickness and serum PRL content of pigeons increased significantly at day 17 of incubation (I17) and day 1 of chick-rearing (R1). In males and females, the mRNA and protein levels of yes-associated transcriptional regulator (YAP) reached the maximum value at R1 and I17, respectively, and phosphorylation level of YAP were minimized at I17. Subcutaneous injection of prolactin on pigeon crops can promote the proliferation of crop epithelium by increasing the connective tissue growth factor (CTGF) level and reducing the phosphorylation level of YAP. YAP-TEAD inhibitor verteporfin can inhibit the proliferation of crop epithelium induced by prolactin by inhibiting YAP and CTGF expression. In conclusion, PRL can participate in crop cell proliferation of pigeons by promoting the expression of YAP and CTGF in Hippo pathway.


Assuntos
Columbidae , Via de Sinalização Hippo , Masculino , Feminino , Animais , Columbidae/fisiologia , Prolactina/farmacologia , Melhoramento Vegetal , Proliferação de Células , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Peso Corporal
4.
Waste Manag ; 169: 52-61, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37406504

RESUMO

Poor properties and high concentrations of heavy metals are still major concerns of successful application of animal manure-derived biochar into the environment. This work thus proposed to add chlorine-based additives (Cl-additives, i.e., CaCl2, MgCl2, KCl, NaCl, and PVC, 50 g Cl/ kg) to improve biochar properties and enhance heavy metal volatilization during swine manure pyrolysis. The results showed that the addition of CaCl2 could improve the retention of carbon (C) by up to 13.1% during pyrolysis, whereas other Cl-additives had little effect on it. Moreover, CaCl2 could enhance the aromaticity of biochar, as indicated by lower H/C ratio than raw biochar. Pretreatment with CaCl2, MgCl2 and PVC reduced phosphorus (P) solubility but increased its bioavailability via the formation of chlorapatite (Ca5(PO4)3Cl). The CaCl2 was more effective for enhancing the volatilization efficiency of heavy metals than other Cl-additives, except for Pb that tended to react with the generated Ca5(PO4)3Cl to form more stable and less volatile Pb5(PO4)3Cl. However, high pyrolysis temperature (900℃) was essential for CaCl2 to simultaneously decrease the bioavailability of heavy metals. Our results indicated that co-pyrolysis of swine manure with CaCl2 is a promising strategy to increase C retention, P bioavailability, and volatilization of heavy metals, and, at higher temperature, reduce the bioavailability of biochar-born heavy metals.


Assuntos
Cloro , Metais Pesados , Suínos , Animais , Esterco , Pirólise , Cloreto de Cálcio , Chumbo , Volatilização , Carvão Vegetal
5.
Adv Healthc Mater ; 12(24): e2300669, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37314335

RESUMO

Adhesives with strong underwater adhesion performance are urgently needed in diverse areas. However, designing adhesives with long-term stability to diverse materials underwater in a facile way is challenging. Here, inspired by aquatic diatoms, a series of novel biomimetic universal adhesives is reported that shows tunable performance with robust and long-lasting stable underwater adhesion to various substrates, including wet biological tissues. The versatile and robust wet-contact adhesives are pre-polymerized by N-[tris(hydroxymethyl)methyl]acrylamide, n-butyl acrylate, and methylacrylic acid in dimethyl sulfoxide and spontaneously coacervated in water triggered by solvent exchange. The synergistic interaction between hydrogen bonding and hydrophobic interaction allows the hydrogels with instant and strong adhesion to various substrate surfaces. The slowly formed covalent bonds enhance cohesion and adhesion strength in hours. The spatial and timescale-dependent adhesion mechanism endows the adhesives with strong and long-lasting stable underwater adhesion to be coupled with fault-tolerant convenient surgical operations.


Assuntos
Adesivos , Diatomáceas , Adesivos/química , Água/química , Solventes , Hidrogéis/química
6.
Molecules ; 28(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37175360

RESUMO

Carbon sequestration is the primary function of biochar. Hence, it is necessary to design biochar with high carbon (C) retention and low C loss. In this study, three P compounds, including KH2PO4, Ca(H2PO4)2, and NH4H2PO4, were premixed with corn stalk (1:4, w/w), aiming to produce biochars (CSB+K, CSB+Ca, and CSB+N) with high C sequestration and slow release of P at three temperatures (300, 500, and 700 °C). The addition of all P sources obviously increased C retention, with the order of NH4H2PO4 (65.6-83.5%) > Ca(H2PO4)2 (60.4-78.2%) > KH2PO4 (50.1-76.1%), compared with the pristine biochar (47.8-73.6%). The addition of Ca(H2PO4)2 and KH2PO4 led to an increase in aromaticity and graphitization, as evidenced by H/C, FTIR, Raman and XPS analysis, whereas an opposite result occurred on CSB+N. Furthermore, all three phosphates reduced C loss of biochars with H2O2 oxidation, and CSB+Ca showed the best effect. Ca(H2PO4)2 and KH2PO4 pretreated biochars had higher resistance to K2Cr2O7 oxidation and thermal treatment. In contrast, the C loss of NH4H2PO4-added biochar at 500 and 700 °C with K2Cr2O7 oxidation was increased by 54% and 36%, respectively. During the pyrolysis process, Ca(H2PO4)2 was transformed into insoluble Ca2P2O7, leading to the lowest P release rate of CSB+Ca. This study indicates that co-pyrolysis of corn stalk and Ca(H2PO4)2 is optimal for increasing C retention, enhancing C stability and improving slow-release performance of P regardless of pyrolysis temperature.


Assuntos
Fosfatos , Fósforo , Temperatura , Sequestro de Carbono , Pirólise , Peróxido de Hidrogênio , Carvão Vegetal , Carbono
7.
J Ginseng Res ; 47(3): 420-428, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37252284

RESUMO

Background: Ginsenoside F2 (GF2), a minor component of Panax ginseng, has been reported to possess a wide variety of pharmacological activities. However, its effects on glucose metabolism have not yet been reported. Here, we investigated the underlying signaling pathways involved in its effects on hepatic glucose. Methods: HepG2 cells were used to establish insulin-resistant (IR) model and treated with GF2. Cell viability and glucose uptake-related genes were also examined by real-time PCR and immunoblots. Results: Cell viability assays showed that GF2 up to 50 µM did not affect normal and IR-HepG2 cell viability. GF2 reduced oxidative stress by inhibiting phosphorylation of the mitogen-activated protein kinases (MAPK) signaling components such as c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (ERK1/2), and p38 MAPK, and reducing the nuclear translocation of NF-κB. Furthermore, GF2 activated PI3K/AKT signaling, upregulated the levels of glucose transporter 2 (GLUT-2) and GLUT-4 in IR-HepG2 cells, and promoted glucose absorption. At the same time, GF2 reduced phosphoenolpyruvate carboxykinase and glucose-6-phosphatase expression as well as inhibiting gluconeogenesis. Conclusion: Overall, GF2 improved glucose metabolism disorders by reducing cellular oxidative stress in IR-HepG2 cells via MAPK signaling, participating in the PI3K/AKT/GSK-3ß signaling pathway, promoting glycogen synthesis, and inhibiting gluconeogenesis.

8.
Plant Physiol Biochem ; 196: 1122-1136, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36907700

RESUMO

Pinus massoniana is an important industrial crop tree species commonly used for timber and wood pulp for papermaking, rosin, and turpentine. This study investigated the effects of exogenous calcium (Ca) on P. massoniana seedling growth, development, and various biological processes and revealed the underlying molecular mechanisms. The results showed that Ca deficiency led to severe inhibition of seedling growth and development, whereas adequate exogenous Ca markedly improved growth and development. Many physiological processes were regulated by exogenous Ca. The underlying mechanisms involved diverse Ca-influenced biological processes and metabolic pathways. Calcium deficiency inhibited or impaired these pathways and processes, whereas sufficient exogenous Ca improved and benefited these cellular events by regulating several related enzymes and proteins. High levels of exogenous Ca facilitated photosynthesis and material metabolism. Adequate exogenous Ca supply relieved oxidative stress that occurred at low Ca levels. Enhanced cell wall formation, consolidation, and cell division also played a role in exogenous Ca-improved P. massoniana seedling growth and development. Calcium ion homeostasis and Ca signal transduction-related gene expression were also activated at high exogenous Ca levels. Our study facilitates the elucidation of the potential regulatory role of Ca in P. massoniana physiology and biology and is of guiding significance in Pinaceae plant forestry.


Assuntos
Fenômenos Biológicos , Pinus , Cálcio/metabolismo , Pinus/genética , Pinus/metabolismo , Proteômica/métodos , Plântula/metabolismo , Crescimento e Desenvolvimento
9.
Life (Basel) ; 13(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984003

RESUMO

Effects of different feeding strategies on meat quality and intestinal development in pigeon squabs were investigated. 120 pairs of pigeons with two squabs each were assigned to five groups (four free-choice feeding systems and one complete feeding system): T1 (corn, pea, wheat, and pelleted feed), T2 (corn, wheat, and pelleted feed), T3 (corn, pea, and pelleted feed), T4 (corn and pelleted feed), and T5 (complete pelleted feed). Compared with T5, the diet in T4 made the breast meat redder and more yellow (p < 0.05). T2 and T4 resulted in an enhanced total superoxide dismutase activity of meat. Breast muscle in T1 and T2 was determined to have higher contents of nonessential amino acids, glycine, alanine, and glutamic acid (p < 0.05). The contents of the essential amino acids, lysine, threonine, valine, histidine, and arginine were also higher in T1 (p < 0.05). Villus height, surface area, and alkaline phosphatase activity of the duodenum and jejunum in T2 were the highest among the treatments (p < 0.05). In conclusion, free-choice feeding system can improve the meat quality and intestinal development of pigeon squabs, but which combination method of whole grains to use in the production depends on the feeding purpose.

10.
J Anim Physiol Anim Nutr (Berl) ; 107(2): 680-690, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35668622

RESUMO

The objective of this study was to explore the carbohydrate contents of crop milk, insulin and glucose concentrations in serum and the expression patterns of AMP-activated protein kinases (AMPKs) and genes related to glucose metabolism in pigeon crops during the breeding period. Crop milk was collected from squabs of rearing Day 1 (R1) to R6. Contents of total sugar and reducing sugar increased to the maximum levels at R6 (p < 0.05). Forty-two pairs of adult pigeons were allotted to seven groups by different breeding stages, and their crops and serum were sampled. No significant differences were found in either insulin or glucose levels in serum. The glucose transporter 2 gene level was the greatest at R15 in females, whereas it was at R7 in males. However, sodium-dependent glucose transporters 1 expression in both sexes decreased from incubation Day 17 (I17) to R7. In females, glucokinase expression peaked at R1, and at R1 and R7 in males. Pyruvate kinase mRNA levels peaked at R7 in females and at R15 males. The mRNA abundance of fructose-1,6-bisphosphatase 1 in both sexes and glucose-6-phosphatase in females decreased after I10. While phosphoenolpyruvate carboxykinase 1 expression decreased after I17 (p < 0.05). Protein levels of AMPKα in crops were minimized at R1 (p < 0.05). In females, expression of AMPKα1 and AMPKα2 was inhibited at I17 and R1 (p < 0.05). In males, AMPKα1 expression was decreased at R7 (p < 0.05) and AMPKα2 was reduced at I10 and R1. pAMPK expression was the lowest at I17 in females, and it was at R7 and R25 in males. Conclusively, glycolysis in pigeon crops was enhanced during chick-rearing, while gluconeogenesis was significantly inhibited. The stability of the insulin level suggests that it was probably not involved in the regulation of glucose metabolism in crop tissues.


Assuntos
Proteínas Quinases Ativadas por AMP , Columbidae , Masculino , Feminino , Animais , Columbidae/fisiologia , Gluconeogênese , Insulina , Glucose , Açúcares , RNA Mensageiro
11.
J Ethnopharmacol ; 302(Pt A): 115865, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36306932

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Centella asiatica (L.) Urb., a potential medicinal plant, is widely used in orient traditional medicine. Its major active constituents include asiaticoside (AS), madecassoside (MS), asiatic acid and madecassic acid. Thereinto, AS is a pentacyclic triterpenoid saponin with a variety of pharmacological effects including antitumor, neuroprotective and wound healing effects. AIM OF THE STUDY: In this review, we summarize the pharmacokinetics, safety and pharmacological properties of AS. MATERIALS AND METHODS: We gathered information about AS from articles published up to 2022 and listed in Google scholar, PubMed, Web of Science, Elsevier, and similar databases. The keywords used in our search included "asiaticoside", "Centella asiatica", "pharmacokinetics", "nerve", "cancer", "skin", etc. RESULTS: AS appeared to degrade through a first-order reaction and had low biotoxicity. However, the pharmacokinetic properties of AS differed according to species. AS is highly blood-brain-barrier permeable without any harmful side effect. It has a variety of pharmacological effects including anti-neural inflammation and anti-cancer properties, as well as protective properties for the skin, cardiovascular system, and pulmonary system. CONCLUSION: This review comprehensively summarized current information regarding the pharmacokinetic and pharmacological properties of AS, and supported the pharmaceutical value of this compound. Future research should focus on improving bioavailability of AS and conducting clinical assessment.


Assuntos
Centella , Triterpenos , Extratos Vegetais/farmacologia , Triterpenos/farmacologia
12.
Front Plant Sci ; 13: 845107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386672

RESUMO

As one of the serious environmental problems worldwide, acid rain (AR) has always caused continuous damage to the forestry ecosystem. Studies have shown that AR can leach calcium ions from plants and soil. Calcium (Ca) is also a crucial regulator of the plant stress response, whereas there are few reports on how Ca regulates the response of AR-resistant woody plants to AR stress. In this study, by setting different exogenous Ca levels, we study the physiological and molecular mechanism of Ca in regulating the Taxus wallichiana var. mairei response to AR stress. Our results showed that low Ca level leads to photosynthesis, and antioxidant defense system decreases in T. wallichiana var. mairei leaves; however, these negative effects could be reversed at high Ca level. In addition, proteomic analyses identified 44 differentially expressed proteins in different Ca level treatments of T. wallichiana var. mairei under AR stress. These proteins were classified into seven groups, which include metabolic process, photosynthesis and energy pathway, cell rescue and defense, transcription and translation, protein modification and degradation, signal transduction, etc. Furthermore, the study found that low Ca level leads to an obvious increase of Ca-related gene expression under AR stress in T. wallichiana var. mairei using qRT-PCR analyses and however can be reversed at high Ca level. These findings would enrich and extend the Ca signaling pathways of AR stress in AR-resistant woody plants and are expected to have important theoretical and practical significance in revealing the mechanism of woody plants tolerating AR stress and protecting forestry ecosystem in soil environment under different Ca levels.

13.
Environ Toxicol ; 36(3): 408-416, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33098623

RESUMO

China is the world's largest rare earth producer and exporter, previous studies have shown that rare earth elements can cause oxidative damage in animal testis. However, the molecular mechanisms underlying these observations have yet to be elucidated. In this paper, male mice were fed with different doses (10, 20, and 40 mg/kg BW) of LaCl3 for 90 consecutive days, regulatory role of nuclear factor erythroid-2 related factor 2 (Nrf-2)/antioxidant response element (ARE) pathway in testicular oxidative stress induced by LaCl3 were investigated. Analysis showed that LaCl3 exposure could lead to severe testicular pathological changes and apoptosis in spermatogenic cells, it up-regulated the peroxidation of lipids, proteins and DNA, and induced the excessive levels of reactive oxygen species (ROS) production in mouse testis, reduced the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione S epoxide transferase (GST) as well as the glutathione (GSH) content. Furthermore, exposure to LaCl3 also downregulated the expression of Nrf2 and its target gene products, including heme oxygenase 1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), NAD(P)H dehydrogenase [quinine] 1(NQO1), protein kinase C (PKC), and phosphatidylinositol 3-kinase (PI3K), but upregulated the expression of Kelch-like ECH-related protein 1 (Keap1) in damaged mouse testes. Collectively, our data imply that the oxidative damage induced by LaCl3 in testis was related to inhibition of the Nrf-2/AREs pathway activation.


Assuntos
Lantânio/toxicidade , Estresse Oxidativo/fisiologia , Animais , Elementos de Resposta Antioxidante , Apoptose , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Heme Oxigenase-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testículo/metabolismo
14.
ACS Appl Mater Interfaces ; 12(38): 42576-42585, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32867474

RESUMO

Surface-tethered hierarchical polymer brushes find wide applications in the development of antibacterial surfaces due to the well-defined spatial distribution and the separate but complementary properties of different blocks. Existing methods to achieve such polymer brushes mainly focused on inorganic material substrates, precluding their practical applications on common medical devices. In this work, a hierarchical polymer brush system is proposed and facilely constructed on polymeric substrates via light living graft polymerization. The polymer brush system with micrometer-scale thickness exhibits a unique hierarchical architecture consisting of a poly(hydroxyethyl methacrylate) (PHEMA) outer layer and an anionic inner layer loading with cationic antimicrobial peptide (AMP) via electrostatic attraction. The surface of this system inhibits the initial adhesion of bacteria by the PHEMA hydration outer layer under neutral pH conditions; when bacteria adhere and proliferate on this surface, the bacterially induced acidification triggers the cleavage of labile amide bonds within the inner layer to expose the positively charged amines and vigorously release melittin (MLT), allowing the surface to timely kill the adhering bacteria. The hierarchical surface employs multiple antibacterial mechanisms to combat bacterial infection and shows high sensitiveness and responsiveness to pathogens. A new paradigm is supplied by this modular hierarchical polymer brushes system for the progress of intelligent surfaces on universal polymer substrates, showing great potential to a promising strategy for preventing infection related to medical devices.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Polímeros/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Aderência Bacteriana/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
15.
J Ginseng Res ; 43(4): 600-605, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31695566

RESUMO

BACKGROUND: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. METHODS: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. RESULTS AND CONCLUSIONS: Two novel, minor triterpenoid saponins, ginsenoside LS1 (1) and 5,6-didehydroginsenoside Rg3 (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with IC50 of 37.38 µM compared with that of NG-monomethyl-L-arginine (IC50 = 90.76 µM). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin E2 and tumor necrosis factor-α. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

16.
J Ethnopharmacol ; 228: 179-187, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30268651

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: A multi-herb Chinese medicinal formula consisting of a variety of medicinal and edible materials has long been consumed as a hot drink and immune enhancer for its efficiency to increase disease resistance in Xinjiang, China. However, no fundamental data has been collected associated with traditional consumption. The present work was designed to evaluate the immunostimulatory role of Xinjiang herbal tea (XMT-WE) in RAW 264.7 macrophages and cyclophosphamide (CTX)-induced immunosuppression mice model. MATERIALS AND METHODS: RAW 264.7 cells were treated with various concentrations of XMT-WE. Nitric oxide (NO) levels were determined using Griess reagents, and pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α were investigated with a cytometric bead array kit. The effects on mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and TNF-α were investigated. Furthermore, activation of nuclear factor (NF)-κB and AP-1 mitogen-activated protein kinase (MAPK) signaling pathways was investigated. RESULTS: Pre-treatment with XMT-WE significantly increased secretion of NO, IL-6, and TNF-α. In addition, XMT-WE markedly increased expression of iNOS, COX-2, and TNF-α as well as AP-1 and NF-κB translocation from the cytoplasm into the nucleus, which was associated with an increase of phosphorylated ERK, JNK, and p38 as well as membrane receptors such as toll-like receptor (TLR) 2 and TLR4. Moreover, XMT-WE promoted the secretion of interleukin-2 (IL-2) and interferon-γ (IFN-γ) in cyclophosphamide (CTX)-induced immunosuppressive mice. CONCLUSION: These results indicated that XMT-WE at 50 µg/ml exerts immunomodulatory activity via TLR2/4-mediated MAPK signaling pathways in RAW 264.7 cells. Furthermore, in vivo experiments revealed that XMT-WE at the dose of 50 and 100 mg/kg strongly stimulated inflammatory cytokines.


Assuntos
Fatores Imunológicos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Chás de Ervas , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Ciclofosfamida , Citocinas/metabolismo , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7 , Transdução de Sinais
17.
Environ Toxicol Pharmacol ; 65: 73-81, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30579107

RESUMO

Senkyunolide H (SNH) is a phthalide isolated from the rhizome of Ligusticum chuanxiong Hort. that has been reported to have several pharmacological activities, including anti-atherosclerotic, antiproliferative, and cytoprotective effects. In this study, we investigated the neuroprotective effects and potential mechanisms of SNH against 1-methyl-4-phenylpyridinium (MPP+)-induced oxidative stress. We demonstrated that SNH pretreatment significantly attenuated MPP+-induced neurotoxicity and apoptosis in PC12 cells. In addition, SNH attenuated the effect of MPP+ on the expression of the pro-apoptotic factors Bax and caspase-3. Meanwhile, SNH prevented oxidative stress by reducing reactive oxygen species generation, mitochondrial membrane potential loss, cytochrome C release, and malondialdehyde levels while increasing antioxidant enzyme activity (e.g., superoxide dismutase, catalase, and glutathione peroxidase). In addition, SNH inhibited nuclear accumulation of nuclear factor-κB and c-Jun N-terminal kinase and phosphorylation p38 mitogen-activated protein kinases (MAPKs). Overall, this investigation provides novel evidence that SNH exerts neuroprotective effects via the ROS-mediated MAPK pathway and represents a potential preventive or therapeutic agent for neuronal disorders.


Assuntos
Benzofuranos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fármacos Neuroprotetores/farmacologia , Espécies Reativas de Oxigênio/metabolismo , 1-Metil-4-fenilpiridínio , Animais , Apoptose/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
18.
Toxicon ; 155: 21-26, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30312692

RESUMO

Patulin often contaminates fruits and fruit-base products, which seriously threats the health of consumers. In this study, ozone was used to degrade patulin in aqueous solution, and investigated the cytotoxicity of patulin after ozone detoxification on human hepatic carcinoma cells (HepG2) using MTT assay and apoptosis assay. Patulin was rapidly degraded from 24.59 mg/L to 9.85 mg/L within 180 s by 10.60 mg/L of ozone at a flow rate of 90 mL/min, and reduced by 59.94%. The half maximal inhibitory concentration (IC50) of patulin on HepG2 cells was 9.32 µmol/L after 24 h of exposure, and it showed a dose dependent effect. After 90 s of ozone detoxification, the cell viability of HepG2 cells obviously increased from 42.31% to 93.96%, and the total apoptotic cells significantly reduced from 22.24% to 11.18% after 180 s of ozone treatment. The results clearly show the great potential of ozone in degrading patulin in liquid foods.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Ozônio/química , Patulina/química , Patulina/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Inativação Metabólica/efeitos dos fármacos , Concentração Inibidora 50 , Oxirredução , Ozônio/farmacologia , Patulina/farmacocinética
19.
Carbohydr Polym ; 198: 537-545, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30093032

RESUMO

Ginsenoside compound K (CK) has been shown to exhibit anticancer properties. In this study, chitosan nanoparticles loaded with ginsenoside compound K (CK-NPs) were prepared as a delivery system using a self-assembly technique with amphipathic deoxycholic acid-O carboxymethyl chitosan as the carrier, which improved the water solubility of CK. By evaluating drug loading, entrapment efficiency, and in vitro release behavior, the feasibility of CK-NPs as a drug carrier nanoparticle for the treatment of human hepatic carcinoma cells (HepG2) was investigated. Result revealed that CK and CK-NPs showed a dose-dependent inhibitory effect on HepG2 cells with IC50 values of 23.33 and 16.58 µg/mL, respectively. Furthermore, fluorescence imaging demonstrated that CK-NPs promoted cellular uptake in vitro. Therefore, all results indicated that CK-NPs might be a novel drug delivery system to improve the solubility and enhance the cytotoxic and apoptotic potentials of CK for effective liver cancer chemotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Quitosana/análogos & derivados , Ácido Desoxicólico/administração & dosagem , Portadores de Fármacos/administração & dosagem , Ginsenosídeos/administração & dosagem , Nanopartículas/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Quitosana/administração & dosagem , Quitosana/química , Ácido Desoxicólico/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Ginsenosídeos/química , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química
20.
Plant Physiol Biochem ; 127: 238-247, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29621720

RESUMO

Acid rain (AR) can induce great damages to plants and could be classified into different types according to the different SO42-/NO3- ratio. However, the mechanism of plants' responding to different types of AR has not been elucidated clearly. Here, we found that nitric-rich simulated AR (N-SiAR) induced less leaves injury as lower necrosis percentage, better physiological parameters and reduced oxidative damage in the leaves of N-SiAR treated Arabidopsis thaliana compared with sulfate and nitrate mixed (SN-SiAR) or sulfuric-rich (S-SiAR) simulated AR treated ones. Of these three types of SiAR, N-SiAR treated Arabidopsis maintained the highest of nitrogen (N) content, nitrate reductase (NR) and nitrite reductase (NiR) activity as well as N metabolism related genes expression level. Nitric oxide (NO) content showed that N-SiAR treated seedlings had a higher NO level compared to SN-SiAR or S-SiAR treated ones. A series of NO production and elimination related reagents and three NO production-related mutants were used to further confirm the role of NO in regulating acid rain resistance in N-SiAR treated Arabidopsis seedlings. Taken together, we concluded that an elevated N metabolism and enhanced NO production are involved in the tolerance to different types of AR in Arabidopsis.


Assuntos
Chuva Ácida/efeitos adversos , Arabidopsis/metabolismo , Óxido Nítrico/biossíntese , Nitrogênio/metabolismo , Estresse Oxidativo
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