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1.
Bioorg Chem ; 134: 106451, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907048

RESUMO

Cytotoxic peptides derived from spider venoms have been considered as promising candidates for anticancer treatment. The novel cell penetrating peptide LVTX-8, which is a 25-residue amphipathic α-helical peptide isolated from spider Lycosa vittata, exhibited potent cytotoxicity and is a potential precursor for further anticancer drug development. Nevertheless, LVTX-8 may be easily degraded by multiple proteases, inducing the proteolytic stability problem and short half-life. In this study, ten LVTX-8-based analogs were rationally designed and the efficient manual synthetic method was established by the DIC/Oxyma based condensation system. The cytotoxicity of synthetic peptides was systematically evaluated against seven cancer cell lines. Seven of the derived peptides exhibited high cytotoxicity towards tested cancer in vitro, which was better than or comparable to that of natural LVTX-8. In particular, both N-acetyl and C-hydrazide modified LVTX-8 (825) and the conjugate methotrexate (MTX)-GFLG-LVTX-8 (827) possessed more durable anticancer efficiency, higher proteolytic stability, as well as lower hemolysis. Finally, we confirmed that LVTX-8 could disrupt the integrity of cell membrane, target the mitochondria and reduce the mitochondrial membrane potential to induce the cell death. Taken together, the structural modifications were conducted on LVTX-8 for the first time and the stability significantly improved derivatives 825 and 827 may provide useful references for the modifications of cytotoxic peptides.


Assuntos
Antineoplásicos , Peptídeos Penetradores de Células , Neoplasias , Venenos de Aranha , Humanos , Venenos de Aranha/farmacologia , Venenos de Aranha/química , Venenos de Aranha/metabolismo , Antineoplásicos/farmacologia , Metotrexato/química , Peptídeos Penetradores de Células/química
2.
Acta Pharmacol Sin ; 44(1): 201-210, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35794372

RESUMO

The use of oncolytic peptides with activity against a wide range of cancer entities as a new and promising cancer therapeutic strategy has drawn increasing attention. The oncolytic peptide LTX-315 derived from bovine lactoferricin (LfcinB) was found to be highly effective against suspension cancer cells, but not adherent cancer cells. In this study, we tactically fused LTX-315 with rhodamine B through a hybridization strategy to design and synthesize a series of nucleus-targeting hybrid peptides and evaluated their activity against adherent cancer cells. Thus, four hybrid peptides, NTP-212, NTP-217, NTP-223 and NTP-385, were synthesized. These hybrid peptides enhanced the anticancer activity of LTX-315 in a panel of adherent cancer cell lines by 2.4- to 37.5-fold. In model mice bearing B16-F10 melanoma xenografts, injection of NTP-385 (0.5 mg per mouse for 3 consecutive days) induced almost complete regression of melanoma, prolonged the median survival time and increased the overall survival. Notably, the administered dose of NTP-385 was only half the effective dose of LTX-315. We further revealed that unlike LTX-315, which targets the mitochondria, NTP-385 disrupted the nuclear membrane and accumulated in the nucleus, resulting in the transfer of a substantial amount of reactive oxygen species (ROS) from the cytoplasm to the nucleus through the fragmented nuclear membrane. This ultimately led to DNA double-strand break (DSB)-mediated intrinsic apoptosis. In conclusion, this study demonstrates that hybrid peptides obtained from the fusion of LTX-315 and rhodamine B enhance anti-adherent cancer cell activity by targeting the nucleus and triggering DNA DSB-mediated intrinsic apoptosis. This study also provides an advantageous reference for nucleus-targeting peptide modification.


Assuntos
Melanoma , Peptídeos , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Apoptose , DNA
3.
J Mater Res ; 38(3): 633-643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741987

RESUMO

Realizing breathable shape memory fiber-based material with antibacterial and waterproof performances is important for multitiered wearable protection to address the increasing concerns of air pollution. Herein, using an alternating electrospinning-electrospraying technology, we develop a fiber-based membrane with Janus wettability based on a silk fibroin nanofibers-substrate (SFNFs), a polyurethane nanospheres-top layer (PUNSs), and a middle layer of PU nanofibers-mat with in-situ grown silver nanoparticles (PUNFs-AgNPs), which serves separately for skin contact, a self-cleaning physical barrier to resist external aerosol/bacteria (PM2.5 filtration efficiency ~ 98.1%), and a bio-barrier that can sterilize harmful particles and inhibit bacteria proliferation (> 95%). This breathable Janus film (SFNFs/PUNFs-AgNPs/PUNSs, SPAP) with an antibacterial filter shows shape memory stretchability enabled by the thermoplastic PU component, which is mechanically adaptive to human body for wearable protection. This work presents a breathable wearable material for air-filtration and anti-bacteria, promising for applications such as wound dressings, medical masks, protection suits, and multifunctional filters. Graphical abstract: An alternating electrospinning-electrospraying technology was proposed to achieve a silk fibroin-based antibacterial membrane with Janus wettability, as well as good skin affinity and breathability, which serves well as physical and bio-barriers for water resistance, PM2.5 filtration (~98.1%) and bacteria inhibition (efficiency of 95%). This shape memory Janus membrane can adapt mechanically to human body curvatures for functional wearable protections. Supplementary Information: The online version contains supplementary material available at 10.1557/s43578-022-00805-w.

4.
Inorg Chem ; 61(25): 9533-9540, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35687844

RESUMO

A metal-organic framework, {Zn3(BTB)2(µ3-OH)[(CH3)2NH2](H2O)}n (1), was synthesized based on H3BTB (1,3,5-tri(4-carboxyphenyl)benzene). An AC impedance test proves that 1 has a relatively high conductivity performance of 1.52 × 10-3 S·cm-1 at 338 K and 98% RH. The proton conductivity of the composite film 1@CS-9 (CS = chitosan) reaches 1.84 × 10-1 S·cm-1 at 328 K and 98% RH. In addition, 1 is discovered to have a good adsorption effect on iodine vapor, and the adsorption capacity reaches 726 mg·g-1. The multifunctionality caused by dimethylamine cations was investigated for the first time, which has implications for multifunctionality generated by host-guest molecules.

5.
Inorg Chem ; 61(38): 15098-15107, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36094135

RESUMO

A series of heterometallic tetranuclear clusters, Ln2Ni2(NO3)4L4(µ3-OCH3)2·2(CH3CN) (Ln = Gd(1), Tb(2), Dy(3), Ho(4), Er(5); HL = methyl 3-methoxysalicylate), were synthesized solvothermally. The intramolecular synergistic effect of two metal centers of Ln(III) and Ni(II) and the exposed multimetallic sites serving as Lewis acid activators greatly increase the efficiency of the CO2 conversion, and the yield for cluster 3 can be achieved at 96% at atmospheric pressure and low temperature. In particular, the self-assembly multimetal center with polydentate ligand shows good generality and enhanced recyclability. The design of such 3d-4f heterometallic clusters provides an effective strategy for the conversion of CO2 under greener conditions. Meanwhile, magnetic investigations indicate that cluster 1 is a good candidate for magnetic refrigerant materials with a relatively large magnetocaloric effect (MCE) (-ΔSm = 28.5 J kg-1 K-1 at 3.0 K and 7.0 T), and cluster 3 shows single-molecular magnet behavior under zero dc field. Heterometallic clusters with special magnetic properties and good catalytic behavior for the conversion of CO2 are rare. Thus, they are potential bifunctional materials applied in practice.

6.
Clin Immunol ; 225: 108679, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33485895

RESUMO

HER2-targeted therapy has not benefited patients with low levels of HER2 expression; however, combination therapy may be effective. Primary analysis of a phase IIb trial investigating the HER2-derived vaccine nelipepimut-S (NPS) did not benefit the intention-to-treat population, but subset analysis showed a benefit in triple-negative breast cancer (TNBC) patients. The subset analysis of this multicenter, randomized, single-blind, phase IIb trial identified significant improvement in 36-month disease-free survival (DFS) between NPS (n = 55) and placebo (n = 44) in TNBC (HR 0.25, p = 0.01) and those who express HLA-A24 (HR 0.41, p = 0.05). The TNBC cohort demonstrated improved 36-month DFS in those with HER2 1+ expression (HR 0.17, p = 0.01), HLA-A24 positivity (HR 0.08, p < 0.01), or in those who received neoadjuvant chemotherapy (HR 0.21, p < 0.01). NPS vaccination with trastuzumab was associated with improved 36-month DFS among patients with TNBC. The observed benefit to this high-risk subgroup warrants confirmation in a phase III trial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Imunoterapia/métodos , Fragmentos de Peptídeos/imunologia , Receptor ErbB-2/imunologia , Trastuzumab/uso terapêutico , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica , Antígeno HLA-A24/metabolismo , Humanos , Análise de Intenção de Tratamento , Recidiva Local de Neoplasia , Efeito Placebo , Medicina de Precisão , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Risco , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/mortalidade
7.
Glycoconj J ; 38(5): 551-560, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34515908

RESUMO

Methylene blue (MB) is one of the most common cationic dyes to detect heparin. As the sulfate residue presented in heparin was the main contributor to bind with MB, the UV performance of the MB with selectively desulfated heparin derivatives was investigated. It was found that the sulfate residue in different heparin analogues did not show the equal ability to attract MB binding. The stoichiometry of sulfate with MB among the heparin and derivatives was verified as a non-constant number. For the two selectively desulfated heparin derivatives: sulfate elimination at 6-O (6-OdeS) and N-acetylated heparin (N-deS-Acetyl), the MB to sulfate ratios were significantly higher than for heparin. For the not fully diminished sulfate at 2-O heparin derivative (2-OdeS), the MB-SO3- ratio of 2-OdeS was between 6-OdeS, N-deS-Acetlyl and heparin. Although in a distinct sulfation position, the MB-SO3- ratio of 6-OdeS and N-deS-Acetyl was almost equal, which agreed with the comparable total desulfation degree between 6-OdeS and N-deS-Acetyl. In addition, compared to heparin groups, the non-desulfated gs-HP showed no significantly different MB-SO3- ratio with heparin. The above results demonstrated that compared with the sulfate location and glycan composition of heparin, the content of sulfate was the most essential factor for the MB binding.


Assuntos
Anticoagulantes/química , Inibidores Enzimáticos/química , Heparina/química , Azul de Metileno/química , Sulfatos/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Estrutura Molecular
8.
Ecotoxicol Environ Saf ; 218: 112284, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33945902

RESUMO

Copper poses huge environmental and public health concerns due to its widespread and persistent use in the past several decades. Although it is well established that at higher levels copper causes nephrotoxicity, the exact mechanisms of its toxicity is not fully understood. Therefore, this experimental study for the first time investigates the potential molecular mechanisms including transcriptomics, metabolomics, serum biochemical, histopathological, cell apoptosis and autophagy in copper-induced renal toxicity in pigs. A total of 14 piglets were randomly assigned to two group (7 piglets per group) and treated with a standard diet (11 mg CuSO4 per kg of feed) and a high copper diet (250 mg CuSO4 per kg of feed). The results of serum biochemical tests and renal histopathology suggested that 250 mg/kg CuSO4 in the diet significantly increased serum creatinine (CREA) and induced renal tubular epithelial cell swelling. Results on transcriptomics and metabolomics showed alteration in 804 genes and 53 metabolites in kidneys of treated pigs, respectively. Combined analysis of transcriptomics and metabolomics indicated that different genes and metabolism pathways in kidneys of treated pigs were involved in glycerophospholipids metabolism and glycosphingolipid metabolism. Furthermore, copper induced mitochondrial apoptosis characterized by increased bax, bak, caspase 3, caspase 8 and caspase 9 expressions while decreased bcl-xl and bcl2/bax expression. Exposure to copper decreased the autophagic flux in terms of increased number of autophagosomes, beclin1 and LC3b/LC3a expression and p62 accumulation. These results indicated that the imbalance of glycosphingolipid metabolism, the impairment of autophagy and increase mitochondrial apoptosis play an important role in copper induced renal damage and are useful mechanisms to understand the mechanisms of copper nephrotoxicity.

9.
J Anim Physiol Anim Nutr (Berl) ; 105(5): 908-915, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33713505

RESUMO

The purpose of this study was to investigate the effects of diet type (normal or low Ca and P diets) and 25(OH)D3 supplementation (with or with not 2000 IU/kg 25(OH)D3 ) during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets. A total of 40 sows, which are at their 7th parity, were divided into four groups: control group (standard diet), low Ca group, 25(OH)D3 group and low Ca plus 25(OH)D3 group respectively (10 in each group). The blood of sows on day 100 and 114 of gestation and newborn piglets was collected for serum biochemical analyses. Results showed that the reproductive performance of sows was not influenced by diet type or 25(OH)D3 supplementation (p > 0.05). And the addition of 25(OH)D3 to diet low Ca group caused that the content of serum TG in sows on day 100 of gestation was not different from that of the control group (p > 0.05). The addition of 25(OH)D3 significantly decreases the content of serum TG in sows on day 114 of gestation (p < 0.05). The addition of 25(OH)D3 significantly increased the content of serum UREA and CREA in newborn piglets (p < 0.05). Overall, feeding 2000 IU/kg 25(OH)D3 to aged sows at late gestation had no effects on reproductive performance, but partly contributed to keeping serum TG balance in sows and may indicate increased pressure on kidneys in newborn piglets.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Animais Recém-Nascidos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Paridade , Gravidez , Suínos , Vitamina D/análogos & derivados
10.
Ecotoxicol Environ Saf ; 206: 111366, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010598

RESUMO

To explore the effects of copper (Cu) on energy metabolism and AMPK-mTOR pathway-mediated autophagy in kidney, a total of 240 one-day-old broiler chickens were randomized into four equal groups and fed on the diets with different levels of Cu (11, 110, 220, and 330 mg/kg) for 49 d. Results showed that excess Cu could induce vacuolar degeneration and increase the number of autophagosomes in kidney, and the adenosine triphosphate (ATP) level and mRNA levels of energy metabolism-related genes were decreased with the increasing dietary Cu level. Moreover, immunohistochemistry and immunofluorescence showed that the positive expressions of Beclin1 and LC3-II were mainly located in cytoplasm of renal tubular epithelial cells and increased significantly with the increasing levels of Cu. The mRNA levels of Beclin1, Atg5, LC3-I, LC3-II, Dynein and the protein levels of Beclin1, Atg5, LC3-II/LC3-I and p-AMPKα1/AMPKα1 were markedly elevated in treated groups compared with control group (11 mg/kg Cu). However, the mRNA and protein levels of p62 and p-mTOR/mTOR were significantly decreased with the increasing levels of Cu. These results suggest that impaired energy metabolism induced by Cu may lead to autophagy via AMPK-mTOR pathway in kidney of broiler chickens.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Cobre/toxicidade , Metabolismo Energético/efeitos dos fármacos , Rim/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Galinhas , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Metabolismo Energético/genética , Rim/metabolismo , Rim/patologia , Transdução de Sinais/efeitos dos fármacos
11.
Ecotoxicol Environ Saf ; 200: 110715, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450432

RESUMO

Copper (Cu) is a necessary trace mineral due to its biological activity. Excessive Cu can induce inflammatory response in humans and animals, but the underlying mechanism is still unknown. Here, 240 broilers were used to study the effects of excessive Cu on oxidative stress and NF-κB-mediated inflammatory responses in immune organs. Chickens were fed with diet containing different concentrations of Cu (11, 110, 220, and 330 mg of Cu/kg dry matter). The experiment lasted for 49 days. Spleen, thymus, and bursa of Fabricius (BF) on day 49 were collected for histopathological observation and assessment of oxidative stress status. Additionally, the mRNA and protein levels of NF-κB and inflammatory cytokines were also analyzed. The results indicated that excess Cu could increase the number and area of splenic corpuscle as well as the ratio of cortex and medulla in thymus and BF. Furthermore, excessive Cu intake could decrease activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); but increase contents of malondialdehyde (MDA), TNF-α, IL-1, IL-1ß; up-regulate mRNA levels of TNF-α, IFN-γ, IL-1, IL-1ß, IL-2, iNOS, COX-2, NF-κB and protein levels of TNF-α, IFN-γ, NF-κB, p-NF-κB in immune organs. In conclusion, excessive Cu could cause pathologic changes and induce oxidative stress with triggered NF-κB pathway, and might further regulate the inflammatory response in immune organs of chicken.


Assuntos
Galinhas/imunologia , Cobre/toxicidade , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Bolsa de Fabricius/enzimologia , Bolsa de Fabricius/imunologia , Bolsa de Fabricius/metabolismo , Bolsa de Fabricius/patologia , Catalase/metabolismo , Galinhas/genética , Galinhas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Glutationa Peroxidase/metabolismo , Inflamação/genética , Inflamação/metabolismo , Malondialdeído/metabolismo , NF-kappa B/genética , Baço/enzimologia , Baço/imunologia , Baço/metabolismo , Baço/patologia , Superóxido Dismutase/metabolismo , Timo/enzimologia , Timo/imunologia , Timo/metabolismo , Timo/patologia
12.
Ecotoxicol Environ Saf ; 190: 110063, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846860

RESUMO

Arsenic is a toxic metalloid that can cause male reproductive malfunctions and is widely distributed in the environment. The aim of this study was to investigate the cytotoxicity of arsenic trioxide (ATO) induced GC-1 spermatogonial (spg) cells. Our results found that ATO increased the levels of catalase (CAT) and malonaldehyde (MDA) and reactive oxygen species (ROS), while decreasing glutathione (GSH) and the total antioxidant capacity (T-AOC). Therefore, ATO triggered oxidative stress in GC-1 spg cells. In addition, ATO also caused severe mitochondrial dysfunction that included an increase in residual oxygen consumption (ROX), and decreased the routine respiration, maximal and ATP-linked respiration (ATP-L-R), as well as spare respiratory capacity (SRC), and respiratory control rate (RCR); ATO also damaged the mitochondrial structure, including mitochondrial cristae disordered and dissolved, mitochondrial vacuolar degeneration. Moreover, degradation of p62, LC3 conversion, increasing the number of acidic vesicle organelles (AVOs) and autophagosomes and autolysosomes are demonstrated that the cytotoxicity of ATO may be associated with autophagy. Meanwhile, the metabolomics analysis results showed that 20 metabolites (10 increased and 10 decreased) were significantly altered with the ATO exposure, suggesting that maybe there are the perturbations in amino acid metabolism, lipid metabolism, glycan biosynthesis and metabolism, metabolism of cofactors and vitamins. We concluded that ATO was toxic to GC-1 spg cells via inducing oxidative stress, mitochondrial dysfunction and autophagy as well as the disruption of normal metabolism. This study will aid our understanding of the mechanisms behind ATO-induced spermatogenic toxicity.


Assuntos
Trióxido de Arsênio/toxicidade , Autofagia/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Glutationa/metabolismo , Lisossomos/metabolismo , Masculino , Metabolômica , Camundongos , Mitocôndrias/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Espermatogônias/enzimologia , Espermatogônias/metabolismo
13.
Sheng Li Xue Bao ; 72(2): 133-138, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32328606

RESUMO

Lycopene is an antioxidant which has potential anti-diabetic activity, but the cellular mechanisms have not been clarified. In this study, different concentrations of lycopene were used to treat pancreatic alpha and beta cell lines, and the changes of cell growth, cell apoptosis, cell cycle, reactive oxygen species (ROS), ATP levels and expression of related cytokines were determined. The results exhibited that lycopene did not affect cell growth, cell apoptosis, cell cycle, ROS and ATP levels of alpha cells, while it promoted the growth of beta cells, increased the ratio of S phase, reduced the ROS levels and increased the ATP levels of beta cells. At the same time, lycopene treatment elevated the mRNA expression levels of tnfα, tgfß and hif1α in beta cells. These findings suggest that lycopene plays cell-specific role and activates pancreatic beta cells, supporting its application in diabetes therapy.


Assuntos
Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Licopeno/farmacologia , Trifosfato de Adenosina/metabolismo , Apoptose , Carotenoides/farmacologia , Ciclo Celular , Células Cultivadas , Citocinas/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo
14.
Anal Chem ; 91(21): 13383-13389, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31580650

RESUMO

We report here a modified aptamer selection method, magnetic cross-linking precipitation (MCP)-SELEX, for highly efficient library enrichment and aptamer isolation. MCP-SELEX isolates bound aptamers via highly efficient chemical cross-linking between amino groups of target proteins and activated carboxylic acid groups on magnetic beads (>90% coupling efficiency). Importantly, MCP-SELEX avoids surface interferences in conventional target-fixed methods and substantially minimizes nonspecific binding. The enrichment efficiencies of MCP-SELEX for various proteins (PD-L1, ubiquitin, thrombin, and HSA) were all greatly higher than those of the conventional target-bound magnetic bead based-SELEX (MB-SELEX). Antithrombin aptamer with KD of 33 nM was successfully isolated by four rounds of MCP-SELEX. MCP-SELEX also enabled the efficient aptamer isolation by coupling with MB-SELEX or falling-off-SELEX. We identified structure-switching aptamers (SSAs) that specifically bind to HSA with low nanomolar dissociation constant via three rounds of MCP-SELEX and 1 round of falling-off-SELEX. Our HSA SSAs also have ∼3-fold higher specificity against streptavidin relative to thrombin SSAs discovered through falling-off-SELEX only. The enriched library has ∼78-fold higher signal-to-noise ratio (the number of DNAs eluted by 50 nM HSA divided by the number of DNAs self-dissociated in blank buffer) than that obtained by 4 rounds of direct falling-off-SELEX. We finally demonstrated the application of the selected SSA in fluorescent detection of HSA in urine with diagnostic required sensitivity and dynamic range. We expect that MCP-SELEX may be coupled with other selection methods to substantially accelerate aptamer discovery.


Assuntos
Antitrombinas/química , Aptâmeros de Nucleotídeos , Precipitação Química , Magnetismo , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnica de Seleção de Aptâmeros/métodos
15.
Avian Pathol ; 48(5): 429-436, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31084377

RESUMO

Ascites syndrome (AS) in chickens is associated with profound vascular remodelling and increased pulmonary artery pressure as well as right ventricular hypertrophy. Classical transient receptor potential cation channels (TRPCs) are key regulators of cardiac hypertrophy that act via regulation of calcium influx in mammals. We investigated whether classical transient receptor potential channels in chickens with right ventricular hypertrophy still possess this mechanism for regulating Ca2+ flux. Intravenous injection of cellulose particles was successfully used to induce AS in chickens, and tissues were examined 22 days after treatment. The chickens in the test group showed cardiac hypertrophy with oedema of the cardiac muscle and disruption of myofilaments. The right-to-total ventricle weight ratio (RV/TV), the levels of serum aspartate aminotransferase (AST) and creatine kinase (CK) of the test group were significantly higher than in the control group. Intracellular calcium levels were significantly increased in cardiomyocytes from chickens in the test group. Gene expression of TRPC3, TRPC4, TRPC5, TRPC6 and TRPC7 in heart tissues from the test group showed no significant differences compared with controls. However, TRPC1 protein levels, as well as mRNA levels, were down-regulated in the heart muscle of AS chickens (P < 0.05). Although we observed an increase in calcium concentration, the expression of TRPC1 decreased in cardiac cells. We hypothesized that an increase in intracellular free calcium concentration could inversely regulate calcium channel expression. RESEARCH HIGHLIGHTS Intracellular Ca2+ levels were increased in the myocardium of AS broilers. Expression of TRPC1, which mediates calcium influx, was decreased in the myocardium of AS broilers. The relationship between intracellular Ca2+ levels and expression of TRPC1 requires further study.


Assuntos
Ascite/veterinária , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Galinhas/fisiologia , Animais , Ascite/patologia , Feminino , Regulação da Expressão Gênica , Masculino , Miocárdio/patologia , Miócitos Cardíacos/patologia , RNA Mensageiro/genética , Canais de Cátion TRPC/genética
16.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067654

RESUMO

As a gaseous biological signaling molecule, nitric oxide (NO) regulates many physiological processes in plants. Over the last decades, this low molecular weight compound has been identified as a key signaling molecule to regulate plant stress responses, and also plays an important role in plant development. However, elucidation of the molecular mechanisms for NO in leaf development has so far been limited due to a lack of mutant resources. Here, we employed the NO-deficient mutant nia1nia2 to examine the role of NO in leaf development. We have found that nia1nia2 mutant plants displayed very different leaf phenotypes as compared to wild type Col-0. Further studies have shown that reactive oxygen species (ROS) levels are higher in nia1nia2 mutant plants. Interestingly, ROS-related enzymes ascorbate peroxidase (APX), catalases (CAT), and peroxidases (POD) have shown decreases in their activities. Our transcriptome data have revealed that the ROS synthesis gene RBOHD was enhanced in nia1nia2 mutants and the photosynthesis-related pathway was impaired, which suggests that NO is required for chloroplast development and leaf development. Together, these results imply that NO plays a significant role in plant leaf development by regulating ROS homeostasis.


Assuntos
Arabidopsis/metabolismo , Homeostase , Óxido Nítrico/metabolismo , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento
17.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959775

RESUMO

The physicochemical properties of four 1-alkyl-3-methylimidazolium bromide ([CnC1im]Br, n = 5, 6, 7, 8) ionic liquids (ILs) were investigated in this work by using inverse gas chromatography (IGC) from 303.15 K to 343.15 K. Twenty-eight organic solvents were used to obtain the physicochemical properties between each IL and solvent via the IGC method, including the specific retention volume and the Flory⁻Huggins interaction parameter. The Hildebrand solubility parameters of the four [CnC1im]Br ILs were determined by linear extrapolation to be δ 2 ( [ C 5 C 1 im ] Br ) = 25.78 (J·cm-3)0.5, δ 2 ( [ C 6 C 1 im ] Br ) = 25.38 (J·cm-3)0.5, δ 2 ( [ C 7 C 1 im ] Br ) =24.78 (J·cm-3)0.5 and δ 2 ( [ C 8 C 1 im ] Br ) = 24.23 (J·cm-3)0.5 at room temperature (298.15 K). At the same time, the Hansen solubility parameters of the four [CnC1im]Br ILs were simulated by using the Hansen Solubility Parameter in Practice (HSPiP) at room temperature (298.15 K). The results were as follows: δ t ( [ C 5 C 1 im ] Br ) = 25.86 (J·cm-3)0.5, δ t ( [ C 6 C 1 im ] Br ) = 25.39 (J·cm-3)0.5, δ t ( [ C 7 C 1 im ] Br ) = 24.81 (J·cm-3)0.5 and δ t ( [ C 8 C 1 im ] Br ) = 24.33 (J·cm-3)0.5. These values were slightly higher than those obtained by the IGC method, but they only exhibited small errors, covering a range of 0.01 to 0.1 (J·cm-3)0.5. In addition, the miscibility between the IL and the probe was evaluated by IGC, and it exhibited a basic agreement with the HSPiP. This study confirms that the combination of the two methods can accurately calculate solubility parameters and select solvents.


Assuntos
Imidazóis/química , Líquidos Iônicos/química , Solubilidade , Brometos/química , Cromatografia Gasosa , Solventes/química
18.
J Biol Chem ; 292(24): 10295-10305, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28468826

RESUMO

Neutrophil elastase (NE) can be rapidly taken up by tumor cells that lack endogenous NE expression, including breast cancer, which results in cross-presentation of PR1, an NE-derived HLA-A2-restricted peptide that is an immunotherapy target in hematological and solid tumor malignancies. The mechanism of NE uptake, however, remains unknown. Using the mass spectrometry-based approach, we identify neuropilin-1 (NRP1) as a NE receptor that mediates uptake and PR1 cross-presentation in breast cancer cells. We demonstrated that soluble NE is a specific, high-affinity ligand for NRP1 with a calculated Kd of 38.7 nm Furthermore, we showed that NRP1 binds to the RRXR motif in NE. Notably, NRP1 knockdown with interfering RNA or CRISPR-cas9 system and blocking using anti-NRP1 antibody decreased NE uptake and, subsequently, susceptibility to lysis by PR1-specific cytotoxic T cells. Expression of NRP1 in NRP1-deficient cells was sufficient to induce NE uptake. Altogether, because NRP1 is broadly expressed in tumors, our findings suggest a role for this receptor in immunotherapy strategies that target cross-presented antigens.


Assuntos
Absorção Fisiológica , Neoplasias da Mama/metabolismo , Apresentação Cruzada , Elastase de Leucócito/metabolismo , Proteínas de Neoplasias/metabolismo , Neuropilina-1/metabolismo , Motivos de Aminoácidos , Anticorpos Bloqueadores/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Feminino , Humanos , Cinética , Elastase de Leucócito/química , Elastase de Leucócito/imunologia , Ligantes , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Neuropilina-1/antagonistas & inibidores , Neuropilina-1/química , Neuropilina-1/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Solubilidade , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
19.
Clin Immunol ; 192: 6-13, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29574039

RESUMO

In this randomized phase Ib trial, we tested combining the E39 peptide vaccine with a vaccine created from E39', an attenuated version of E39. Patients with breast or ovarian cancer, who were disease-free after standard of care therapy, were enrolled and randomized to one of three arms. Arm EE received six E39 inoculations; arm EE' received three E39 inoculations followed by three E39'; and arm E'E received three E39' inoculations, followed by three E39. Within each arm, the first five patients received 500 µg of peptide and the remainder received 1000 µg. Patients were followed for toxicity, and immune responses were measured. This initial analysis after completion of the primary vaccination series has confirmed the safety of both vaccines. Immune analyses suggest incorporating the attenuated version of the peptide improves immune responses and that sequencing of E39 followed by E39' might produce the optimal immune response. TRIAL REGISTRATION: NCT02019524.


Assuntos
Neoplasias da Mama/imunologia , Vacinas Anticâncer/imunologia , Receptores de Folato com Âncoras de GPI/imunologia , Neoplasias Ovarianas/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/terapia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/efeitos adversos , Feminino , Humanos , Hipersensibilidade Tardia/etiologia , Hipersensibilidade Tardia/imunologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/terapia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Vacinação/métodos , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos
20.
Cell Physiol Biochem ; 45(3): 1097-1107, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29439255

RESUMO

BACKGROUND/AIMS: 14-3-3ζ is involved in the regulation of PI3K/Akt pathway which is closely associated with carcinogenesis. However, the clinical significance of combined detection of 14-3-3ζ and p-Akt in hepatocellular carcinoma (HCC) remains unclear. METHODS: Two-hundred pairs of HCC and adjacent liver specimens were subjected to tissue microarray. The association of 14-3-3ζ and p-Akt levels with the postoperative survival and recurrence in HCC patients was analyzed with univariate and multivariate methods. Moreover, the effects of 14-3-3ζ overexpression on the growth of HCC and the expressions of p-Akt and HIF-1α were assessed in a xenograft mouse model. RESULTS: Elevated levels of 14-3-3ζ and p-Akt were detected in HCC and a positive correlation between the levels of 14-3-3ζ and p-Akt was verified. HCC patients with satellite nodules, microvascular invasion, portal vein tumor thrombosis, poor tumor differentiation and an advanced tumor stage tended to have higher levels of 14-3-3ζ and p-Akt. In addition, the postoperative 3-, 5-, and 7-year overall survival rates in HCC patients with 14-3-3ζhigh and p-Akthigh were significantly lower compared with those with 14-3-3ζlow and p-Aktlow, and the cumulative recurrence rate in HCC patients with 14-3-3ζhigh and p-Akthigh was significantly higher than that in those with 14-3-3ζlow and p-Aktlow. The multivariate Cox proportional hazard analysis indicated that concomitant upregulation of 14-3-3ζ and p-Akt was an independent factor that predicted poor survival and high recurrence in HCC patients. Furthermore, animal experiment showed that overexpression of 14-3-3ζ accelerated the growth of HCC xenograft tumors and induced the expressions of p-Akt and HIF-1α in vivo. CONCLUSION: Co-upregulation of 14-3-3ζ and p-Akt predicts poor prognosis in patients with HCC, and 14-3-3ζ-induced activation of the Akt signaling pathway contributes to HCC progression.


Assuntos
Proteínas 14-3-3/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Regulação para Cima , Proteínas 14-3-3/metabolismo , Idoso , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Feminino , Antígenos E da Hepatite B/sangue , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
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