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1.
Immunology ; 169(3): 292-308, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36726218

RESUMO

The reported enterovirus A 71 (EVA71) vaccines and immunoglobin G (IgG) antibodies have no cross-antiviral efficacy against other enterovirus A (EV-A) which caused hand, foot and mouth disease (HFMD). Here we constructed an IgM antibody (20-IgM) based on our previous discovery to address the resistance encountered by IgG-based immunotherapy. Although binding to the same conserved neutralizing epitope within the GH loop of EV-As VP1, the antiviral breath and potency of 20-IgM are still higher than its parental 20-IgG1. The 20-IgM blocks the interaction between the EV-As and its receptors, scavenger receptor class B, member 2 (SCARB2) and Kringle-containing transmembrane protein 1(KREMEN1) of the host cell. The 20-IgM also neutralizes the EV-As at the post-attachment stages, including postattachment neutralization, uncoating and RNA release inhibition after internalization. Mechanistically, the dual blockage effect of 20-IgM is dependent on both a conserved site targeting and high affinity binding. Meanwhile, 20-IgM provides cross-antiviral efficacy in EV-As orally infected neonatal ICR mice. Collectively, 20-IgM and its property exhibit excellent antiviral activity with a dual-blockage inhibitory effect at both the pre- and post-attachment stages. The finding enhances our understanding of IgM-mediated immunity and highlights the potential of IgM subtype antibodies against enterovirus infections.


Assuntos
Enterovirus Humano A , Doença de Mão, Pé e Boca , Animais , Camundongos , Anticorpos Neutralizantes , Enterovirus Humano A/química , Enterovirus Humano A/genética , Camundongos Endogâmicos ICR , Imunoglobulina G , Imunoglobulina M
2.
Exp Eye Res ; 190: 107823, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600485

RESUMO

Administration of RC28-E, a VEGF/bFGF dual decoy receptor (IgG1 Fc-fusion protein), have shown relative therapeutic value in ocular in vivo models, including laser-induced choroidal neovascularization (CNV) in monkeys and streptozotocin (STZ)-induced diabetic retinopathy (DR) in rats. In the present study, we have elucidated the pharmacokinetics profiles of RC28-E at the systemic, vitreous and aqueous humor after administration in a primate model (Macaca fascicularis). Moreover, here we tease out the ocular tissue distribution of RC28-E after intravitreal administration, and we also determine the systemic bioavailability after both intravitreal and intravenous administration. Our results show that RC28-E is rapidly and well-distributed into ocular tissues after intravitreal administration. Drug exposure in choroid and retina was approximately one-quarter and one-twelfth of that in vitreous humor, while its half-life in vitreous and aqueous humor were well-sustained (3.3 and 3.0 days). Remarkably, RC28-E could cross the blood-ocular barrier, and the systemic bioavailability of RC28-E was ~25%. No drug accumulation after multiple administration was noticed, but low titers of antibody produce against RC28-E were detected. Overall, RC28-E exhibited high clinical value due to adequate pharmacokinetic profiling, safety and efficacy.


Assuntos
Humor Aquoso/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacocinética , Proteínas Recombinantes de Fusão/farmacocinética , Fator A de Crescimento do Endotélio Vascular/farmacocinética , Corpo Vítreo/metabolismo , Animais , Disponibilidade Biológica , Barreira Hematorretiniana , Corioide/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Fator 2 de Crescimento de Fibroblastos/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Injeções Intravítreas , Cristalino/metabolismo , Macaca fascicularis , Masculino , Proteínas Recombinantes de Fusão/imunologia , Retina/metabolismo , Distribuição Tecidual , Fator A de Crescimento do Endotélio Vascular/imunologia
3.
J Ethnopharmacol ; 305: 116115, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36587881

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Berberis lycium Royle, a member of the Berberidaceae family, is a high-value medicinal plant with a documented history of usage in traditional medicine and has demonstrated significant therapeutic results among local populations throughout the globe. It is used traditionally in many parts of Pakistan to treat diarrhea, abdominal spasms, coughs, and chest problems. AIM OF THE STUDY: To investigate the antispasmodic, bronchodilator, and antidiarrheal effects of B. lycium and its possible underlying mechanisms through in silico, in vitro, and in vivo studies. MATERIALS AND METHODS: LC ESI-MS/MS analysis was used to identify bioactive components within the hydromethanolic extract of B. lycium. In silico studies, including network pharmacology and molecular docking, were utilized to investigate the antispasmodic and bronchodilator properties of the extract's bioactive components. In vitro pharmacological studies were conducted using isolated rabbit jejunum, trachea, urinary bladder, and rat ileum preparations. In vivo antidiarrheal activities were conducted in mice, including castor oil-induced diarrhea, intestinal transit, and castor oil-induced enteropooling. RESULTS: The LC ESI-MS/MS analysis of the hydromethanolic extract of B. lycium identified 38 bioactive compounds. Network pharmacology study demonstrated that the mechanism of BLR for the treatment of diarrhea might involve IL1B, TLR4, PIK3R1, TNF, PTPRC, IL2, PIK3CD, and ABCB1, whereas, for respiratory ailments, it may involve PIK3CG, TRPV1, STAT3, ICAM1, ACE, PTGER2, PTGS2, TNF, MMP9, NOS2, IL2, CCR5, HRH1, and VDR. Molecular docking research revealed that chlorogenic acid, epigallocatechin, isorhamnetin, quinic acid, gallic acid, camptothecin, formononetin-7-O-glucoside, velutin, caffeic acid, and (S)-luteanine exhibited a higher docking score than dicyclomine with validated proteins of smooth muscle contractions such as CACB2_HUMAN, ACM3_HUMAN, MYLK_HUMAN, and PLCG1_HUMAN. In vitro investigations demonstrated that Blr.Cr, Blr.EtOAc, and Blr.Aq relaxed spontaneously contracting jejunum preparations; carbachol (1 µM)-induced and K+ (80 mM)-induced jejunum, trachea, and urinary bladder contractions in a concentration-dependent manner, similar to dicyclomine. Moreover, Blr.Cr, Blr.EtOAc, and Blr.Aq exhibited a rightward shift in Ca+2 and carbachol cumulative response curves, similar to dicyclomine, demonstrating the coexistence of antimuscarinic and Ca+2 antagonistic mechanisms due to the presence of alkaloids and flavonoids. In vivo antidiarrheal activities showed that the hydromethanolic extract was significantly effective against castor oil-induced diarrhea and castor oil-induced enteropooling, similar to loperamide, and charcoal meal intestinal transit, similar to atropine, in mice at doses of 50, 100, and 200 mg/kg body weight, which supports its traditional use in diarrhea. CONCLUSION: The dual blocking mechanism of muscarinic receptors and Ca+2 channels behind the smooth muscle relaxing activity reveals the therapeutic relevance of B. lycium in diarrhea, abdominal spasms, coughs, and chest problems.


Assuntos
Berberis , Lycium , Ratos , Humanos , Camundongos , Animais , Coelhos , Antidiarreicos/farmacologia , Antidiarreicos/uso terapêutico , Parassimpatolíticos/farmacologia , Parassimpatolíticos/uso terapêutico , Broncodilatadores/farmacologia , Óleo de Rícino , Diciclomina/efeitos adversos , Carbacol/farmacologia , Tosse/induzido quimicamente , Tosse/tratamento farmacológico , Interleucina-2/efeitos adversos , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Íleo , Ratos Sprague-Dawley , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Diarreia/metabolismo , Espasmo
4.
Eur J Pharm Sci ; 121: 251-259, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-29715501

RESUMO

BACKGROUND: Clinical anti-vascular epithelial growth factor (VEGF) therapy trials faced a major challenge due to upregulated expression of other pro-angiogenic factors, such as fibroblast growth factor-2 (FGF-2). RC28, a novel recombinant dual decoy receptor IgG1 Fc-fusion protein, can block VEGFA and FGF-2 simultaneously. It is designed for the treatment of neovascular age-related macular degeneration and other pathological ocular neovascularization. The present study investigated the prevention efficacy of RC28 on choroidal neovascularization (CNV) in a monkey model and compared to the other mono VEGF antagonists; biodistribution and pharmacokinetics performance were also investigated. METHODS: ELISA and endothelial cell proliferation, migration, and tubule formation assay evaluated the bioactivity of RC28 in vitro, and an initial comparison was made among the mono target antagonists, Bevacizumab (Avastin), Ranibizumab (Lucentis), Aflibercept (EYLEA), Conbercept (KH902), and Ranibizumab (Lucentis). Laser-induced CNV in monkeys, and both VEGF and FGF-2 serum levels were detected in animals before and after the CNV model were induced. RC28 prevention efficacy was compared to other VEGF antagonists on CNV with respect to the incidence of CNV and several ophthalmic examinations. Ocular and systemic levels of RC28 were analyzed by 89Zr-labeled RC28 after single intravitreal administration for the biodistribution and pharmacokinetic profiles. RESULTS: RC28 is a unique fusion protein with high affinity to both VEGF and FGF-2, and beneficial to in vitro and in vivo bioactivity. The in vivo pharmacological studies demonstrated that the incidence of CNV formation was largely reduced in RC28 treatment groups with a low dosage as compared to other VEGF antagonist control groups. Furthermore, traces of RC28 were detected as dispersing from eyeballs to the liver after 20 days, and a prolonged half-time pharmacokinetic profile was exhibited.


Assuntos
Neovascularização de Coroide/metabolismo , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Proteínas Recombinantes de Fusão/farmacologia , Neovascularização Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Neovascularização de Coroide/fisiopatologia , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Fragmentos Fab das Imunoglobulinas/genética , Macaca mulatta , Masculino , Ranibizumab/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão/genética , Neovascularização Retiniana/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
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