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1.
Food Chem ; 449: 139223, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604032

RESUMO

Recently some major safety concerns have been raised on organic contaminants in widely consumed plants such as coffee. Hence, this study aimed to develop specifically optimized methods for determining organic contaminants, such as pesticides and polychlorinated biphenyls (PCBs), in coffee using GC-MS/MS and LC-MS/MS. QuEChERS method was used as a base extraction method, and 27 experiments were studied using design of experiments with categorical variables (extraction buffers, cleanup sorbents, and coffee roasting degree) to find the optimum method for each matrix type. The optimum method for green coffee was acetate buffer and chitosan for clean-up, while no-buffer extraction and the PSA + C18 method were ideal for light and dark-roasted coffee. The optimized methods were validated in accordance with SANTE/11312/2021. Furthermore, ten real samples (4 green, and 6 roasted) from the markets were analysed; ortho-phenylphenol was found in all the roasted coffee samples, and carbendazim was found in one green coffee sample.


Assuntos
Coffea , Café , Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Café/química , Contaminação de Alimentos/análise , Coffea/química , Bifenilos Policlorados/análise , Bifenilos Policlorados/química , Cromatografia Líquida/métodos , Ensaios de Triagem em Larga Escala/métodos , Praguicidas/análise , Praguicidas/química
2.
Bioengineered ; 15(1): 2302246, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38214443

RESUMO

Most anti-CD40 antibodies show robust agonism only upon binding to FcγR+ cells, such as B cells, macrophages, or DCs, but a few anti-CD40 antibodies display also strong intrinsic agonism dependent on the recognized epitope and/or isotype. It is worth mentioning, however, that also the anti-CD40 antibodies with intrinsic agonism can show a further increase in agonistic activity when bound by FcγR-expressing cells. Thus, conventional antibodies appear not to be sufficient to trigger the maximum possible CD40 activation independent from FcγR-binding. We proved here the hypothesis that oligomeric and oligovalent anti-CD40 antibody variants generated by genetic engineering display high intrinsic, thus FcγR-independent, agonistic activity. We generated tetra-, hexa- and dodecavalent variants of six anti-CD40 antibodies and a CD40-specific nanobody. All these oligovalent variants, even when derived of bivalent antagonistic anti-CD40 antibodies, showed strongly enhanced CD40 agonism compared to their conventional counterparts. In most cases, the CD40 agonism reached the maximum response induced by FcγR-bound anti-CD40 antibodies or membrane CD40L, the natural engager of CD40. In sum, our data show that increasing the valency of anti-CD40 antibody constructs by genetic engineering regularly results in molecules with high intrinsic agonism and level out the specific limitations of the parental antibodies.


Assuntos
Imunoglobulina G , Receptores de IgG , Imunoglobulina G/genética , Receptores de IgG/genética , Antígenos CD40/genética , Ligante de CD40/genética , Engenharia Genética
3.
Theranostics ; 14(2): 496-509, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169605

RESUMO

Background: Selective TNFR2 activation can be used to treat immune pathologies by activating and expanding regulatory T-cells (Tregs) but may also restore anti-tumour immunity by co-stimulating CD8+ T-cells. Oligomerized TNFR2-specific TNF mutants or anti-TNFR2 antibodies can activate TNFR2 but suffer either from poor production and pharmacokinetics or in the case of anti-TNFR2 antibodies typically from the need of FcγR binding to elicit maximal agonistic activity. Methods: To identify the major factor(s) determining FcγR-independent agonism of anti-TNFR2 antibodies, we systematically investigated a comprehensive panel of anti-TNFR2 antibodies and antibody-based constructs differing in the characteristics of their TNFR2 binding domains but also in the number and positioning of the latter. Results: We identified the domain architecture of the constructs as the pivotal factor enabling FcγR-independent, thus intrinsic TNFR2-agonism. Anti-TNFR2 antibody formats with either TNFR2 binding sites on opposing sites of the antibody scaffold or six or more TNFR2 binding sites in similar orientation regularly showed strong FcγR-independent agonism. The affinity of the TNFR2 binding domain and the epitope recognized in TNFR2, however, were found to be of only secondary importance for agonistic activity. Conclusion: Generic design principles enable the generation of highly active bona fide TNFR2 agonists from nearly any TNFR2-specific antibody.


Assuntos
Receptores de IgG , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral/agonistas , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Receptores de IgG/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T Reguladores , Anticorpos/metabolismo , Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
4.
Clin Ophthalmol ; 17: 2429-2441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37609643

RESUMO

Background: Glaucoma is a degenerative optic neuropathy that causes anatomical and functional visual impairment. Aim and Objectives: This investigation's primary goal was to perform a qualitative and quantitative assessment of macular and peripapillary vessels to detect the impairment of blood flow in glaucomatous patients with or without myopia which can affect the prognosis of glaucoma and visual field. Subjects and Methods: This prospective, cross-sectional, observational research was performed for glaucomatous patients with and without myopia who attend the outpatient clinic at the ophthalmology department, at Benha University. The study was conducted on 50 subjects with glaucomatous eyes, divided into two groups: the first group consisted of (25 subjects) of glaucoma with myopia and the second group (25 subjects) of glaucoma with the same severity of mean deviation in the visual field of group 1 without myopia, using OCTA to measure retinal vessel density (superficial vessel density) and OCT thickness ILM-RPE, RNFL thickness, GCL and small vessel density (RADIAL PERI PAPILLARY PLEXUS). Results: Regarding demographic data of myopia in the studied eyes, there were (9) 18% with low myopia with no significance, (32) 64% with moderate myopia, and (9) 18% with high myopia, with open-angle glaucoma patients showed a highly significant decline in total retinal nerve fiber layer thickness, superior-nasal RNFL thickness, Inferior-nasal RNFL thickness, superior-temporal RNFL and inferior-temporal RNFL thickness compared to open-angle glaucoma patients without myopia. Conclusion: Our results show that microvascular attenuation occurs more significantly in OAG than in myopia. When both myopia and OAG are present, there is a higher reduction in microvascular attenuation than with either disease alone. The development and progression of glaucoma in individuals with high myopia are more aggressive than in low or non-myopia, so by using OCTA detection of early microvascular changes in high myopia, individuals help the early detection and management of glaucoma.

5.
Front Immunol ; 14: 1194610, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545514

RESUMO

Fibroblast growth factor (FGF)-inducible 14 (Fn14) activates the classical and alternative NFκB (nuclear factor 'kappa-light-chain-enhancer' of activated B-cells) signaling pathway but also enhances tumor necrosis factor (TNF)-induced cell death. Fn14 expression is upregulated in non-hematopoietic cells during tissue injury and is also often highly expressed in solid cancers. In view of the latter, there were and are considerable preclinical efforts to target Fn14 for tumor therapy, either by exploiting Fn14 as a target for antibodies with cytotoxic activity (e.g. antibody-dependent cellular cytotoxicity (ADCC)-inducing IgG variants, antibody drug conjugates) or by blocking antibodies with the aim to interfere with protumoral Fn14 activities. Noteworthy, there are yet no attempts to target Fn14 with agonistic Fc effector function silenced antibodies to unleash the proinflammatory and cell death-enhancing activities of this receptor for tumor therapy. This is certainly not at least due to the fact that anti-Fn14 antibodies only act as effective agonists when they are presented bound to Fcγ receptors (FcγR). Thus, there are so far no antibodies that robustly and selectively engage Fn14 signaling without triggering unwanted FcγR-mediated activities. In this study, we investigated a panel of variants of the anti-Fn14 antibody 18D1 of different valencies and domain architectures with respect to their inherent FcγR-independent ability to trigger Fn14-associated signaling pathways. In contrast to conventional 18D1, the majority of 18D1 antibody variants with four or more Fn14 binding sites displayed a strong ability to trigger the alternative NFκB pathway and to enhance TNF-induced cell death and therefore resemble in their activity soluble (TNF)-like weak inducer of apoptosis (TWEAK), one form of the natural occurring ligand of Fn14. Noteworthy, activation of the classical NFκB pathway, which naturally is predominately triggered by membrane-bound TWEAK but not soluble TWEAK, was preferentially observed with a subset of constructs containing Fn14 binding sites at opposing sites of the IgG scaffold, e.g. IgG1-scFv fusion proteins. A superior ability of IgG1-scFv fusion proteins to trigger classical NFκB signaling was also observed with the anti-Fn14 antibody PDL192 suggesting that we identified generic structures for Fn14 antibody variants mimicking soluble and membrane-bound TWEAK.


Assuntos
Neoplasias , Receptores de IgG , Humanos , Receptores de IgG/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Receptor de TWEAK/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , NF-kappa B/metabolismo , Proteínas de Transporte , Imunoglobulina G/metabolismo
6.
Sci Adv ; 9(24): eadf8748, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327341

RESUMO

Staphylococcus aureus is the leading cause of skin and soft tissue infections and is a major health burden due to the emergence of antibiotic-resistant strains. To address the unmet need of alternative treatments to antibiotics, a better understanding of the protective immune mechanisms against S. aureus skin infection is warranted. Here, we report that tumor necrosis factor (TNF) promoted protection against S. aureus in the skin, which was mediated by bone marrow-derived immune cells. Furthermore, neutrophil-intrinsic TNF receptor (TNFR) signaling directed immunity against S. aureus skin infections. Mechanistically, TNFR1 promoted neutrophil recruitment to the skin, whereas TNFR2 prevented systemic bacterial dissemination and directed neutrophil antimicrobial functions. Treatment with a TNFR2 agonist showed therapeutic efficacy against S. aureus and Pseudomonas aeruginosa skin infections, which involved increased neutrophil extracellular trap formation. Our findings revealed nonredundant roles for TNFR1 and TNFR2 in neutrophils for immunity against S. aureus and can be therapeutically targeted for protection against bacterial skin infections.


Assuntos
Neutrófilos , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Infecções Estafilocócicas/tratamento farmacológico
7.
Front Immunol ; 14: 1115667, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051245

RESUMO

Many new immunotherapeutic approaches aim on the stimulatory targeting of receptors of the tumor necrosis factor (TNF) receptor superfamily (TNFRSF) using antibodies with intrinsic or conditional agonism. There is an initial need to characterize corresponding TNFRSF receptor (TNFR)-targeting antibodies with respect to affinity, ligand binding, receptor activation and the epitope recognized. Here, we report a collection of simple and matched protocols enabling the detailed investigation of these aspects by help of Gaussia princeps luciferase (GpL) fusion proteins and analysis of interleukin-8 (IL8) production as an easily measurable readout of TNFR activation. In a first step, the antibodies and antibody variants of interest are transiently expressed in human embryonal kidney 293 cells, either in non-modified form or as fusion proteins with GpL as a reporter domain. The supernatants containing the antibody-GpL fusion proteins can then be used without further purification in cell-free and/or cellular binding studies to determine affinity. Similarly, binding studies with mutated TNFR variants enable the characterization of the antibody binding site within the TNFR ectodomain. Furthermore, in cellular binding studies with GpL fusion proteins of soluble TNFL molecules, the ability of the non-modified antibody variants to interfere with TNFL-TNFR interaction can be analyzed. Last but not least, we describe a protocol to determine the intrinsic and the Fc gamma receptor (FcγR)-dependent agonism of anti-TNFR antibodies which exploits i) the capability of TNFRs to trigger IL8 production in tumor cell lines lacking expression of FcγRs and ii) vector- and FcγR-transfected cells, which produce no or only very low amounts of human IL8. The presented protocols only require standard molecular biological equipment, eukaryotic cell culture and plate readers for the quantification of luminescent and colorimetric signals.


Assuntos
Interleucina-8 , Receptores de IgG , Humanos , Receptores de IgG/metabolismo , Interleucina-8/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Anticorpos , Linhagem Celular Tumoral , Luciferases
9.
Front Immunol ; 13: 888274, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769484

RESUMO

Tumor necrosis factor (TNF) receptor-2 (TNFR2) has attracted considerable interest as a target for immunotherapy. Indeed, using oligomeric fusion proteins of single chain-encoded TNFR2-specific TNF mutants (scTNF80), expansion of regulatory T cells and therapeutic activity could be demonstrated in various autoinflammatory diseases, including graft-versus-host disease (GvHD), experimental autoimmune encephalomyelitis (EAE) and collagen-induced arthritis (CIA). With the aim to improve the in vivo availability of TNFR2-specific TNF fusion proteins, we used here the neonatal Fc receptor (FcRn)-interacting IgG1 molecule as an oligomerizing building block and generated a new TNFR2 agonist with improved serum retention and superior in vivo activity. Methods: Single-chain encoded murine TNF80 trimers (sc(mu)TNF80) were fused to the C-terminus of an in mice irrelevant IgG1 molecule carrying the N297A mutation which avoids/minimizes interaction with Fcγ-receptors (FcγRs). The fusion protein obtained (irrIgG1(N297A)-sc(mu)TNF80), termed NewSTAR2 (New selective TNF-based agonist of TNF receptor 2), was analyzed with respect to activity, productivity, serum retention and in vitro and in vivo activity. STAR2 (TNC-sc(mu)TNF80 or selective TNF-based agonist of TNF receptor 2), a well-established highly active nonameric TNFR2-specific variant, served as benchmark. NewSTAR2 was assessed in various in vitro and in vivo systems. Results: STAR2 (TNC-sc(mu)TNF80) and NewSTAR2 (irrIgG1(N297A)-sc(mu)TNF80) revealed comparable in vitro activity. The novel domain architecture of NewSTAR2 significantly improved serum retention compared to STAR2, which correlated with efficient binding to FcRn. A single injection of NewSTAR2 enhanced regulatory T cell (Treg) suppressive activity and increased Treg numbers by > 300% in vivo 5 days after treatment. Treg numbers remained as high as 200% for about 10 days. Furthermore, a single in vivo treatment with NewSTAR2 upregulated the adenosine-regulating ectoenzyme CD39 and other activation markers on Tregs. TNFR2-stimulated Tregs proved to be more suppressive than unstimulated Tregs, reducing conventional T cell (Tcon) proliferation and expression of activation markers in vitro. Finally, singular preemptive NewSTAR2 administration five days before allogeneic hematopoietic cell transplantation (allo-HCT) protected mice from acute GvHD. Conclusions: NewSTAR2 represents a next generation ligand-based TNFR2 agonist, which is efficiently produced, exhibits improved pharmacokinetic properties and high serum retention with superior in vivo activity exerting powerful protective effects against acute GvHD.


Assuntos
Encefalomielite Autoimune Experimental , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Animais , Encefalomielite Autoimune Experimental/metabolismo , Imunoglobulina G/metabolismo , Camundongos , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Linfócitos T Reguladores
10.
Molecules ; 26(10)2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-34065773

RESUMO

The present study reports the synthesis of new purine bioisosteres comprising a pyrazolo[3,4-d]pyrimidine scaffold linked to mono-, di-, and trimethoxy benzylidene moieties through hydrazine linkages. First, in silico docking experiments of the synthesized compounds against Bax, Bcl-2, Caspase-3, Ki67, p21, and p53 were performed in a trial to rationalize the observed cytotoxic activity for the tested compounds. The anticancer activity of these compounds was evaluated in vitro against Caco-2, A549, HT1080, and Hela cell lines. Results revealed that two (5 and 7) of the three synthesized compounds (5, 6, and 7) showed high cytotoxic activity against all tested cell lines with IC50 values in the micro molar concentration. Our in vitro results show that there is no significant apoptotic effect for the treatment with the experimental compounds on the viability of cells against A549 cells. Ki67 expression was found to decrease significantly following the treatment of cells with the most promising candidate: drug 7. The overall results indicate that these pyrazolopyrimidine derivatives possess anticancer activity at varying doses. The suggested mechanism of action involves the inhibition of the proliferation of cancer cells.


Assuntos
Antineoplásicos/síntese química , Compostos de Benzilideno/síntese química , Biomarcadores Tumorais/metabolismo , Neoplasias/metabolismo , Pirazóis/química , Pirimidinas/química , Células A549 , Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos de Benzilideno/química , Compostos de Benzilideno/farmacologia , Biomarcadores Tumorais/química , Células CACO-2 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Concentração Inibidora 50 , Antígeno Ki-67/química , Antígeno Ki-67/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Neoplasias/tratamento farmacológico
11.
Clin Ophthalmol ; 15: 1145-1151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33758497

RESUMO

PURPOSE: To present outcomes of surgical management of primary congenital glaucoma (PCG) in children less than one year of age in a population based at the Nile Delta. METHODS: A retrospective review of medical records of patients with PCG less than one year of age at presentation who underwent surgical intervention in a tertiary care facility based at the Nile Delta. All patients underwent measurement of intraocular pressure (IOP), horizontal corneal diameter (HCD), cup-to-disc ratio (CDR) before and after surgery and a minimum of 6 months follow up was required. Surgical success was defined as IOP less than 22mmHg without medications and without progression of main disease parameters. RESULTS: The review revealed 44 eyes of 26 consecutive patients who underwent surgical treatment for PCG. Average age at surgery was 5.2 months and mean follow up was 18.5 months. Preoperative IOP was 28.5±4 mmHg, HCD was 13.7±0.7mm, and CDR (when visible) was 0.65±0.18. A total of 69 surgical procedures were performed with an average of 1.56 procedures per eye. Postoperative IOP was 13.3±4.8 mmHg, HCD was 12.8±0.9mm, and CDR was 0.3±0.2 (P<0.0001). Surgical success was achieved in 32 eyes (72.7%) while sight-threatening postoperative complications were reported in 3 eyes. CONCLUSION: Surgical management of PCG younger than one year of age achieved good success rate in the region of the Nile Delta with low rate of visually significant postoperative complications. However, larger studies with longer follow up are needed to fully reveal the overall characteristics of PCG in the region.

12.
Arch Biochem Biophys ; 691: 108513, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32721435

RESUMO

OBJECTIVES: MLN4924 is an inhibitor of NEDD8-activating enzyme (NAE) that interferes with the cullin-RING ubiquitin ligase complexes formation and the nuclear factor kappa B (NF-κB) activation. Here, we investigated the cytotoxic effect of MLN4924 and its ability to sensitize a broad range of cancer cells of different origins to tumour necrosis factor-α (TNF)-induced cell death alongside unravelling its mechanism of action. MATERIALS AND METHODS: Cell viability and caspases processing were determined after MLN4924 treatment either alone or with zVAD-fmk (pan caspase inhibitor), necrostatin-1 (nec-1, RIPK1 inhibitor) and necrosulfonamide (NSA, MLKL inhibitor). Moreover, MLN4924 ability to potentiate TNF-induced cell death was evaluated in 24 cell lines of different cancer origins. The impact of NAE inhibition with MLN4924 on TNF-induced apoptosis and necroptosis was evaluated using zVAD-fmk and nec-1, respectively. RESULTS: MLN4924 alone was able to induce cell death in different cell lines that was attributed to apoptosis induction. Also, MLN4924 sensitized different cancer cell lines to TNF-induced cell death. MLN4924/TNF-induced cell death was apoptosis and necroptosis dependent that may be attributed to MLN4924 inhibition of NF-κB pathway activation. CONCLUSIONS: Targeting NAE and NF-κB pathway with MLN4924 represents a substantial approach to enhance the sensitivity of diverse types of cancer cells. Moreover, the broad in vitro screening of MLN4924 anticancer activity provides a valuable guidance for elucidating the susceptible cancer types for the prospective clinical application of MLN4924.


Assuntos
Apoptose/efeitos dos fármacos , Ciclopentanos/farmacologia , Inibidores Enzimáticos/farmacologia , Necroptose/efeitos dos fármacos , Pirimidinas/farmacologia , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Linhagem Celular Tumoral , Humanos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
13.
BMC Ophthalmol ; 20(1): 298, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32689972

RESUMO

BACKGROUND: To compare surgical outcomes and complications of three inferior oblique weakening procedures; Inferior Oblique Myectomy (IOM), Inferior Oblique combined Resection-Anterior Transposition (IORAT) and Inferior Oblique Anterior Transposition (IOAT) in the management of unilateral Superior Oblique (SO) palsy. METHODS: Retrospective review of medical records of all patients with unilateral SO palsy who underwent one of the aforementioned IO weakening procedures at Benha University hospital was performed. Patients were excluded if surgery was bilateral or combined with other vertical muscle surgery. Primary outcome parameters were improvement of Hypertropia (HT) in primary gaze, side gazes, on alternate head turn, Inferior Oblique Overaction (IOOA), Superior Oblique Underaction (SOUA), correction of head tilt and postoperative complications. RESULTS: The review reveals a total of 65 patients with unilateral SO palsy; 54 congenital and 11 acquired, who met the study criteria and were classified into 3 groups; IOM group (24cases), IORAT group (19cases) and IOAT group (22cases). Compared with IOM, both IORAT and IOAT induced significant correction of HT in primary position, ipsilateral gaze, contralateral head tilt and IOOA. IORAT was significantly more effective than IOAT in correction of HT in ipsilateral gaze and contralateral head tilt while there was no statistical difference between the three groups in correction of HT in ipsilateral gaze, contralateral head tilt and SOUA. Postoperative Anti-elevation was significantly recorded following IORAT (6 cases, 31%) than IOAT (3 cases, 13%) and IOM (one cases, 4%). CONCLUSIONS: The IORAT and IOAT were more superior to IOM in correction of IOOA and HT in the primary position and some other gaze positions. However, superiority of IORAT over the other two procedures should be weighed against its significant association with postoperative underaction of IO muscle and anti-elevation syndrome.


Assuntos
Músculos Oculomotores , Estrabismo , Humanos , Músculos Oculomotores/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Paralisia , Estudos Retrospectivos , Estrabismo/cirurgia , Resultado do Tratamento
14.
J Nat Prod ; 82(11): 3033-3046, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31642313

RESUMO

Three new naphthylisoquinoline dimers, jozibrevines A-C (1a-c), were isolated from the West African shrub Ancistrocladus abbreviatus, along with the known dimer jozimine A2 (1d). The two molecular moieties of 1a-d are coupled via the sterically constrained 3',3″-positions of their two naphthalene units, so that the central biaryl linkage is rotationally hindered. With the two outer axes also being chiral, 1a-d possess three consecutive stereogenic axes. The four isolated dimers all have the same constitutions and identical absolute configurations at the four stereogenic centers, but differ by their axial chirality. They belong to the extremely small class of Dioncophyllaceae-type naphthylisoquinoline dimers, i.e., being devoid of oxygen functions at C-6 and bearing the R-configuration at C-3 in their isoquinoline portions. Besides these dimers, the plant produces predominantly typical Ancistrocladaceae-type monomeric compounds, i.e., with the S-configuration at C-3 and an oxygen function at C-6, such as the new ancistrobrevines K (5) and L (6). Furthermore, a new hybrid-type (i.e., mixed Ancistrocladaceae/Dioncophyllaceae-type) alkaloid was identified, named ancistrobrevine M (7), which is 3R-configured and 6-oxygenated. Remarkable was the discovery of its "inverse hybrid-type" counterpart, dioncoline A (8). It is the as yet only known 3S-configured naphthylisoquinoline lacking an O-functionality at C-6. The new jozibrevines A-C (1a-c) exhibited pronounced antiplasmodial activities in the submicromolar range, with 1a being the most potent compound (IC50, 0.012 µM). Furthermore, jozimine A2 (1d) showed cytotoxicity against human colon carcinoma (HT-29), fibrosarcoma (HT1080), and multiple myeloma (MM.1S) cancer cells, displaying IC50 values of 12.0, 9.0, and 5.0 µM, respectively, whereas jozibrevines A (1a) and B (1b) were nontoxic in this concentration range.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Caryophyllales/química , Isoquinolinas/química , Isoquinolinas/farmacologia , Naftalenos/química , Naftalenos/farmacologia , África Ocidental , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HT29 , Humanos , Estrutura Molecular , Raízes de Plantas/química , Plasmodium falciparum/efeitos dos fármacos
15.
Mar Drugs ; 17(8)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395834

RESUMO

In the present study, LC-HRESIMS-assisted dereplication along with bioactivity-guided isolation led to targeting two brominated oxindole alkaloids (compounds 1 and 2) which probably play a key role in the previously reported antibacterial, antibiofilm, and cytotoxicity of Callyspongia siphonella crude extracts. Both metabolites showed potent antibacterial activity against Gram-positive bacteria, Staphylococcus aureus (minimum inhibitory concentration (MIC) = 8 and 4 µg/mL) and Bacillus subtilis (MIC = 16 and 4 µg/mL), respectively. Furthermore, they displayed moderate biofilm inhibitory activity in Pseudomonas aeruginosa (49.32% and 41.76% inhibition, respectively), and moderate in vitro antitrypanosomal activity (13.47 and 10.27 µM, respectively). In addition, they revealed a strong cytotoxic effect toward different human cancer cell lines, supposedly through induction of necrosis. This study sheds light on the possible role of these metabolites (compounds 1 and 2) in keeping fouling organisms away from the sponge outer surface, and the possible applications of these defensive molecules in the development of new anti-infective agents.


Assuntos
Alcaloides/farmacologia , Callyspongia/química , Oxindóis/farmacologia , Animais , Anti-Infecciosos/farmacologia , Antiprotozoários/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Células HT29 , Halogenação , Humanos , Oceano Índico , Testes de Sensibilidade Microbiana/métodos
16.
Cell Death Dis ; 9(11): 1084, 2018 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-30349023

RESUMO

TNF-like weak inducer of apoptosis (TWEAK) and inhibition of protein synthesis with cycloheximide (CHX) sensitize for poly(I:C)-induced cell death. Notably, although CHX preferentially enhanced poly(I:C)-induced apoptosis, TWEAK enhanced primarily poly(I:C)-induced necroptosis. Both sensitizers of poly(I:C)-induced cell death, however, showed no major effect on proinflammatory poly(I:C) signaling. Analysis of a panel of HeLa-RIPK3 variants lacking TRADD, RIPK1, FADD, or caspase-8 expression revealed furthermore similarities and differences in the way how poly(I:C)/TWEAK, TNF, and TRAIL utilize these molecules for signaling. RIPK1 turned out to be essential for poly(I:C)/TWEAK-induced caspase-8-mediated apoptosis but was dispensable for this response in TNF and TRAIL signaling. TRADD-RIPK1-double deficiency differentially affected poly(I:C)-triggered gene induction but abrogated gene induction by TNF completely. FADD deficiency abrogated TRAIL- but not TNF- and poly(I:C)-induced necroptosis, whereas TRADD elicited protective activity against all three death inducers. A general protective activity against poly(I:C)-, TRAIL-, and TNF-induced cell death was also observed in FLIPL and FLIPS transfectrants.


Assuntos
Apoptose/fisiologia , Citocina TWEAK/metabolismo , Necrose/metabolismo , Poli I-C/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Caspase 8/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cicloeximida/farmacologia , Proteína de Domínio de Morte Associada a Fas/metabolismo , Células HeLa , Humanos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
17.
Mar Drugs ; 16(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134565

RESUMO

A new cyclic hexapeptide, nocardiotide A (1), together with three known compounds-tryptophan (2), kynurenic acid (3), and 4-amino-3-methoxy benzoic acid (4)-were isolated and identified from the broth culture of Nocardiopsis sp. UR67 strain associated with the marine sponge Callyspongia sp. from the Red Sea. The structure elucidation of the isolated compounds were determined based on detailed spectroscopic data including ¹D and ²D nuclear magnetic resonance (NMR) experimental analyses in combination with high resolution electrospray ionization mass spectrometry (HR-ESI-MS), while the absolute stereochemistry of all amino acids components of nocardiotide A (1) was deduced using Marfey's method. Additionally, ten known metabolites were dereplicated using HR-ESI-MS analysis. Nocardiotide A (1) displayed significant cytotoxic effects towards the murine CT26 colon carcinoma, human HeLa cervix carcinoma, and human MM.1S multiple myeloma cell lines. The results obtained revealed sponge-associated Nocardiopsis as a substantial source of lead natural products with pronounced pharmacological activities.


Assuntos
Actinobacteria/química , Antineoplásicos/farmacologia , Callyspongia/microbiologia , Peptídeos Cíclicos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Organismos Aquáticos/microbiologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Oceano Índico , Camundongos , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação
18.
J Interferon Cytokine Res ; 37(7): 310-316, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28472595

RESUMO

The major complication of hepatitis C virus (HCV) infection is the induction of hepatic fibrosis. In this study, we investigated the correlation between the expression level of vascular endothelial growth factor (VEGFA) at mRNA and protein levels and the progression of HCV-related liver fibrosis. One hundred twenty subjects were selected for this study: 15 controls and 105 chronic HCV patients with different fibrosis grades (44 F0-F1 and 61 F2-F4). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure VEGFA mRNA in peripheral blood mononuclear cells, while enzyme-linked immunosorbent assay (ELISA) was used to measure the secreted VEGFA protein in serum. Both qRT-PCR and ELISA results showed that HCV patients have significantly higher VEGFA expression than that of controls (P = 0.036 and 0.043, respectively). Moreover, patients with late fibrotic stages (F2-F4) exhibited the highest levels of VEGFA mRNA and protein (P = 0.008 and 0.041, respectively) when compared with controls. An area under the receiver operating characteristic curve (AUC of the ROC) for the circulatory VEGFA protein between HCV patients with fibrosis and healthy controls was 0.92 (P = 0.043). Our data suggest that VEGFA protein is a promising noninvasively diagnostic biomarker for HCV-induced liver fibrosis.


Assuntos
Hepacivirus/fisiologia , Cirrose Hepática/sangue , Cirrose Hepática/virologia , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Biomarcadores/sangue , Feminino , Regulação da Expressão Gênica , Humanos , Leucócitos Mononucleares , Cirrose Hepática/genética , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC
19.
Viral Immunol ; 28(9): 509-16, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26505957

RESUMO

The aim of this study was to assess the impact of genetic variants of oligoadenylate synthetase 1 (OAS1) single-nucleotide polymorphism (SNP) rs10774671 at the exon 7 splice acceptor site on liver fibrosis progression and hepatitis C virus (HCV) outcome in Egyptian HCV genotype 4 patients. In this study, 195 subjects were enrolled; 60 controls and 135 chronic HCV genotype 4 patients with different fibrosis grades. All subjects were genotyped for OAS1 SNP rs10774671 polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. There was an increasing trend of liver fibrosis progression as 52.9% GG, 73.6% GA, and 83.3% AA genotypes were detected in late fibrosis patients (p = 0.025). The AA genotype was higher in the late fibrosis group than in the early fibrosis group (83.3% vs. 16.7%) (p = 0.001). The A allele was significantly affecting the liver fibrosis progression rate, more than the G allele (p = 0.001). The multivariate analysis showed that the OAS1 GA and AA genotypes were independent factors associated with liver progression (p = 0.009, odds ratio [OR] 3.467, 95% confidence interval [CI] 1.273-7.584). In addition, the A allele was associated with liver fibrosis progression (p = 0.014, OR 2.525, 95% CI 1.157-4.545). The polymorphism at OAS1 exon 7 rs3741981 might be a potential genetic marker and can be useful in the assessment of liver fibrosis progression and disease outcome in HCV-infected patients.


Assuntos
2',5'-Oligoadenilato Sintetase/genética , Éxons , Genótipo , Hepacivirus/classificação , Hepatite C Crônica/complicações , Cirrose Hepática/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Alelos , Progressão da Doença , Egito , Feminino , Técnicas de Genotipagem , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prognóstico
20.
J Interferon Cytokine Res ; 35(8): 641-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25868067

RESUMO

To evaluate the frequency of single-nucleotide polymorphism at the -88 myxovirus resistance (MxA) gene promoter region in relation to the status of hepatitis C virus (HCV) progression and response to combined interferon (IFN) in chronic HCV Egyptian patients. One hundred ten subjects were enrolled in the study; 60 HCV genotype 4-infected patients who underwent combined IFN therapy and 50 healthy individuals. All subjects were genotyped for -88 MxA polymorphism by the restriction fragment length polymorphism technique. There was an increasing trend of response to combined IFN treatment as 34.9% of GG, 64.3% of GT, and 66.7% of TT genotypes were sustained responders (P=0.05). The T allele was significantly affecting the response rate more than G allele (P=0.032). Moreover, the hepatic fibrosis score and hepatitis activity were higher in GG genotypes compared with the GT and TT genotypes. The multivariate analysis showed that the MxA GG genotype was an independent factor increasing the no response to IFN therapy (P=0.04, odds ratio [OR] 3.822, 95% confidence interval [CI] 1.056-11.092), also MxA G allele (P=0.0372, OR 2.905, 95% CI 1.066-7.919). MxA -88 polymorphism might be a potential biomarker to predict response to IFN and disease progression in chronic HCV-infected patients.


Assuntos
Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Proteínas de Resistência a Myxovirus/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adulto , Alelos , Estudos de Casos e Controles , Progressão da Doença , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral
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