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1.
Artigo em Inglês | MEDLINE | ID: mdl-38309493

RESUMO

Janus kinase (JAK) inhibitors are effective anti-inflammatory agents for treatment of ulcerative colitis (UC).1 According to drug regulatory agencies and international guidelines, JAK inhibitors should be avoided during pregnancy and lactation.2-4 The existing evidence on safety of JAK inhibitors during pregnancy is scarce and almost exclusively limited to tofacitinib.4-7.

2.
Pediatr Res ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012309

RESUMO

BACKGROUND: We aimed to evaluate the predictors of sustainability of biologic drugs for paediatric patients with Crohn's disease (CD). METHODS: The Czech National Prospective Registry of Biologic and Targeted Therapy of Inflammatory Bowel Disease (CREdIT) was used to identify the biologic treatment courses in paediatric patients with CD. Mixed-effects Cox models and propensity score analyses were employed to evaluate predictors of treatment sustainability. RESULTS: Among the 558 observations of 473 patients, 264 were treated with adalimumab (47%), 240 with infliximab (43%), 41 with ustekinumab (7%), and 13 with vedolizumab (2%). Multivariable analysis revealed higher discontinuation risk with infliximab compared to adalimumab (HR = 0.600, 95%CI 0.389-0.926), both overall and in first-line treatment (HR = 0.302, 95%CI 0.103-0.890). Infliximab versus adalimumab was associated with shorter time to escalation (HR = 0.094, 95%CI 0.043-0.203). Propensity-score analysis demonstrated lower sustainability of infliximab (HR = 0.563, 95%CI 1.159-2.725). The time since diagnosis to treatment initiation (HR = 0.852, 95%CI 0.781-0.926) was the most important predictor. Baseline immunosuppressive therapy prolonged sustainability with infliximab (HR = 2.899, 95%CI 1.311-6.410). CONCLUSIONS: Given the results suggesting shorter sustainability, the need for earlier intensification and thus higher drug exposure, and the greater need for immunosuppression with infliximab than with adalimumab, the choice of these drugs cannot be considered completely equitable. IMPACT: Our study identified predictors of sustainability of biologic treatment in paediatric patients with Crohn's disease, including adalimumab (versus infliximab), early initiation of biologic treatment, and normalised baseline haemoglobin levels. Infliximab treatment was associated with earlier intensification, higher drug exposure, and a greater need for immunosuppression. Parents and patients should be fully informed of the disadvantages of intravenous infliximab versus adalimumab during the decision-making process. This study emphasises the importance of not delaying the initiation of biologic therapy in paediatric patients with Crohn's disease.

3.
J Pept Sci ; 29(7): e3478, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36633503

RESUMO

Insulin is a peptide responsible for regulating the metabolic homeostasis of the organism; it elicits its effects through binding to the transmembrane insulin receptor (IR). Insulin mimetics with agonistic or antagonistic effects toward the receptor are an exciting field of research and could find applications in treating diabetes or malignant diseases. We prepared five variants of a previously reported 20-amino acid insulin-mimicking peptide. These peptides differ from each other by the structure of the covalent bridge connecting positions 11 and 18. In addition to the peptide with a disulfide bridge, a derivative with a dicarba bridge and three derivatives with a 1,2,3-triazole differing from each other by the presence of sulfur or oxygen in their staples were prepared. The strongest binding to IR was exhibited by the peptide with a disulfide bridge. All other derivatives only weakly bound to IR, and a relationship between increasing bridge length and lower binding affinity can be inferred. Despite their nanomolar affinities, none of the prepared peptide mimetics was able to activate the insulin receptor even at high concentrations, but all mimetics were able to inhibit insulin-induced receptor activation. However, the receptor remained approximately 30% active even at the highest concentration of the agents; thus, the agents behave as partial antagonists. An interesting observation is that these mimetic peptides do not antagonize insulin action in proportion to their binding affinities. The compounds characterized in this study show that it is possible to modulate the functional properties of insulin receptor peptide ligands using disulfide mimetics.


Assuntos
Insulina , Receptor de Insulina , Insulina/metabolismo , Dissulfetos/química , Peptídeos/química
4.
J Pept Sci ; 29(4): e3461, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36336650

RESUMO

Insulin is a key hormone involved in the regulation of overall energetic homeostasis of the organism. The dimeric character of the receptor for insulin evokes ideas about its activation or inhibition with peptide dimers that could either trigger or block the structural transition of the insulin receptor, leading to its activation. Herewith, we present the chemical engineering and biological characterization of several series of insulin dimers or dimers of specific peptides that should be able to bind receptors for insulin or insulin growth factor 1. The hormones or peptides in the dimers were interconnected with different linkers, consisting of triazole moieties and 3, 6, 8, 11, or 23 polyethylene glycol units. The prepared dimers were weaker in binding to insulin receptors than human insulin. However, some of the insulin dimers showed preferential binding specificity toward the isoform A of the insulin receptor, and the insulin dimers also stimulated the insulin receptor more strongly than would be consistent with their binding affinities. Our results suggest that designing insulin dimers may be a promising strategy for modulating the ability of the hormone to activate the receptor or to alter its specificity toward insulin receptor isoforms.


Assuntos
Peptídeos , Receptor de Insulina , Humanos , Receptor de Insulina/metabolismo , Peptídeos/química , Insulina/metabolismo , Isoformas de Proteínas , Polietilenoglicóis
5.
J Pediatr Gastroenterol Nutr ; 76(2): e36-e44, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36705698

RESUMO

OBJECTIVES: We prospectively compared the postvaccination immunity to messenger ribonucleic acid BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine of our pediatric patients over 12 years old with inflammatory bowel disease (IBD) to that of healthy controls and looked for predictors of its robustness. METHODS: Anti-receptor binding domain, anti-spike S2, and anti-nucleocapsid immunoglobin-G (IgG) and immunoglobin-A levels were measured in 139 pediatric patients with IBD [65 fully vaccinated (2 doses), median age 16.3, interquartile range (IQR) 15.2-17.8 years, median time from vaccination (IQR) 61.0 (42.0-80.0) days] and 1744 controls (46, 37-57 years) using microblot array. RESULTS: All IBD and control patients developed positive anti-receptor binding domain IgG antibodies at comparable titers. The proportion of observations with positive anti-spike S2 IgG was higher in patients with IBD than in controls [63% vs 21%, odds ratio 2.99 (1.51-5.90)], as was its titer [median (IQR) 485 (92-922) vs 79 [33-180] IU/mL]. Anti-receptor binding domain and anti-spike S2 IgG levels were associated with IBD status. We found an association between anti-spike S2 IgG levels and time since vaccination (ß -4.85, 95% CI -7.14 to 2.71, P = 0.0001), history of SARS-CoV-2 polymerase chain reaction positivity (206.76, 95% CI 39.93-374.05, P = 0.0213), and anti-tumor necrosis factor treatment (-239.68, 95% CI -396.44-83.55, P = 0.0047). Forty-three percent of patients reported vaccination side effects (mostly mild). Forty-six percent of observations with positive anti-nucleocapsid IgG had a history of SARS-CoV-2 infection. CONCLUSIONS: Patients with IBD produced higher levels of postvaccination anti-spike S2 antibodies than controls. Previous SARS-CoV-2 infection is associated with higher production of postvaccination antibodies and anti-tumor necrosis factor treatment with lower production.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Humanos , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunoglobulina G , Necrose , SARS-CoV-2 , Fator de Necrose Tumoral alfa , Vacinação , Adolescente , Adulto , Pessoa de Meia-Idade
6.
Bioorg Chem ; 107: 104548, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33358613

RESUMO

Multi-orthogonal molecular scaffolds can be applied as core structures of bioactive compounds. Here, we prepared four tri-orthogonal scaffolds based on adamantane or proline skeletons. The scaffolds were used for the solid-phase synthesis of model insulin mimetics bearing two different peptides on the scaffolds. We found that adamantane-derived compounds bind to the insulin receptor more effectively (Kd value of 0.5 µM) than proline-derived compounds (Kd values of 15-38 µM) bearing the same peptides. Molecular dynamics simulations suggest that spacers between peptides and central scaffolds can provide greater flexibility that can contribute to increased binding affinity. Molecular modeling showed possible binding modes of mimetics to the insulin receptor. Our data show that the structure of the central scaffold and flexibility of attached peptides in this type of compound are important and that different scaffolds should be considered when designing peptide hormone mimetics.


Assuntos
Adamantano/química , Insulina/análogos & derivados , Prolina/química , Receptor de Insulina/metabolismo , Animais , Sítios de Ligação , Humanos , Insulina/síntese química , Insulina/metabolismo , Cinética , Simulação de Dinâmica Molecular , Ligação Proteica , Estabilidade Proteica , Estrutura Quaternária de Proteína , Ratos , Receptor de Insulina/química , Técnicas de Síntese em Fase Sólida , Estereoisomerismo
7.
Eur J Pediatr ; 180(9): 3001-3008, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33876264

RESUMO

Studies showing a substantial frequency of dermatologic complications in paediatric Crohn's disease (CD) patients on anti-tumour necrosis factor (TNF) therapy preferentially include patients treated with infliximab. We aimed to identify risk factors for the cumulative incidence of skin complications in a paediatric cohort receiving either adalimumab or infliximab and found an association between current skin complications and the patient's current clinical condition. This study retrospectively evaluated dermatologic complications in an inception cohort of 100 paediatric CD patients receiving the first anti-TNF (Motol PIBD cohort). Patient data were collected every 3 months. The lesions were classified as psoriatic, atopic dermatitis, or others. We used Cox regression to evaluate the association between predefined variables and the time to complication and a generalised linear mixed model to assess the association between the patient's current condition and the occurrence of complications. Among the 89 included children, 35 (39%) presented with dermatologic lesions. The only predictor associated with any complication was infliximab (versus adalimumab) therapy (hazard ratio [HR]: 2.07; 95% confidence interval [CI]: 1.03-4.17; p = 0.04). Infliximab therapy (HR: 5.5; 95%CI: 1.59-19.06; p = 0.01) and a family history of atopy (HR: 3.4; 95%CI 1.35-8.57, p = 0.002) were associated with early manifestation of atopic dermatitis. Lower C-reactive protein levels (odds ratio [OR], 0.947; 95% CI, - 0.898 to 0.998; p = 0.046) and infliximab (versus adalimumab) were associated with the occurrence of any dermatologic complications (OR, 5.93; 95% CI, 1.59-22.07; p = 0.008).Conclusion: The frequency of skin complications seems high in paediatric CD patients treated with anti-TNF and is even higher in those treated with infliximab. What is Known: •The dermatologic complications occur during treatment with anti-tumour necrosis factor. •The frequency of skin complications in paediatric patients with Crohn's disease is high. What is New: •Infliximab (vs. adalimumab) was identified as a strong risk factor for the cumulative incidence of skin complications. •Lower C-reactive protein levels were associated with the current occurrence of dermatologic complications.


Assuntos
Doença de Crohn , Inibidores do Fator de Necrose Tumoral , Criança , Doença de Crohn/complicações , Doença de Crohn/tratamento farmacológico , Humanos , Infliximab/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Fator de Necrose Tumoral alfa
8.
J Biol Chem ; 294(46): 17371-17382, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31558604

RESUMO

Information on how insulin and insulin-like growth factors 1 and 2 (IGF-1 and -2) activate insulin receptors (IR-A and -B) and the IGF-1 receptor (IGF-1R) is crucial for understanding the difference in the biological activities of these peptide hormones. Cryo-EM studies have revealed that insulin uses its binding sites 1 and 2 to interact with IR-A and have identified several critical residues in binding site 2. However, mutagenesis studies suggest that Ile-A10, Ser-A12, Leu-A13, and Glu-A17 also belong to insulin's site 2. Here, to resolve this discrepancy, we mutated these insulin residues and the equivalent residues in IGFs. Our findings revealed that equivalent mutations in the hormones can result in differential biological effects and that these effects can be receptor-specific. We noted that the insulin positions A10 and A17 are important for its binding to IR-A and IR-B and IGF-1R and that A13 is important only for IR-A and IR-B binding. The IGF-1/IGF-2 positions 51/50 and 54/53 did not appear to play critical roles in receptor binding, but mutations at IGF-1 position 58 and IGF-2 position 57 affected the binding. We propose that IGF-1 Glu-58 interacts with IGF-1R Arg-704 and belongs to IGF-1 site 1, a finding supported by the NMR structure of the less active Asp-58-IGF-1 variant. Computational analyses indicated that the aforementioned mutations can affect internal insulin dynamics and inhibit adoption of a receptor-bound conformation, important for binding to receptor site 1. We provide a molecular model and alternative hypotheses for how the mutated insulin residues affect activity.


Assuntos
Fator de Crescimento Insulin-Like I/química , Insulina/química , Receptor IGF Tipo 1/química , Receptor de Insulina/química , Anormalidades Múltiplas/genética , Sequência de Aminoácidos/genética , Sítios de Ligação/genética , Transtornos do Crescimento/genética , Humanos , Insulina/análogos & derivados , Insulina/síntese química , Insulina/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/química , Fator de Crescimento Insulin-Like II/genética , Mutação/genética , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica/genética , Domínios Proteicos/genética , Receptor IGF Tipo 1/genética , Receptor de Insulina/genética
9.
Scand J Gastroenterol ; 51(2): 196-202, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26329773

RESUMO

BACKGROUND: Discontinuation of anti-TNF therapy in patients with inflammatory bowel diseases (IBD) in remission remains a controversial issue. The aims of our study were to assess the proportion of patients who relapse after cessation of biological treatment, and to identify potential risk factors of disease relapse. METHODS: Consecutive IBD patients who discontinued anti-TNF therapy in steroid-free clinical and endoscopic remission were prospectively followed. Multiple logistic regression and Cox proportional-hazards models were used to assess the predictors of disease relapse. RESULTS: Seventy-eight IBD patients (Crohn's disease, CD 61; ulcerative colitis, UC 17) were included and followed for a median of 30 months (range 7-47). A total of 32 (53%) CD patients and nine (53%) UC patients relapsed by the end of the follow-up with a median time to relapse of 8 months (range 1-25) in CD patients and 14 months (range 4-37) in UC patients, respectively. The cumulative probabilities of maintaining remission at 6, 12, and 24 months were 82%, 59%, and 51% in CD patients, and 77%, 77%, and 64% in UC patients, respectively. Survival of CD patients who were in deep remission (clinical and endoscopic healing; faecal calprotectin <150 mg/kg; CRP ≤5 mg/l) was not better compared with those who did not fulfill these criteria. In multivariate models, only colonic CD protected patients from disease relapse. CONCLUSIONS: Approximately half of the IBD patients relapsed within 2 years after anti-TNF discontinuation. In CD patients, no difference between those who were or were not in deep remission was found. Colonic localization protected patients from relapse.


Assuntos
Adalimumab/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Infliximab/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab/efeitos adversos , Adolescente , Adulto , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Proteína C-Reativa/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Progressão da Doença , Endoscopia Gastrointestinal , Fezes/química , Feminino , Seguimentos , Humanos , Infliximab/efeitos adversos , Complexo Antígeno L1 Leucocitário/análise , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Indução de Remissão , Fatores de Risco , Fatores de Tempo , Suspensão de Tratamento , Adulto Jovem
10.
BMC Genet ; 16: 53, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25997498

RESUMO

BACKGROUND: Alliinase is an important enzyme occurring in Allium species that converts precursors of sulfuric compounds, cysteine sulfoxides into a biologically active substance termed allicin. Allicin facilitates garlic defense against pests and produces health-promoting compounds. Alliinase is encoded by members of a multigene family that has not yet been sufficiently characterized, namely with regard to the copy numbers occurring within the genome and the polymorphisms among the family members. RESULTS: We cloned 45 full-length alliinase amplicons of cultivar (cv.) Jovan. Sequence analyses revealed nine different sequence variants (SVs), confirming the multilocus nature of this gene family. Several mutations in exons, mainly occurring in the first exon coding for vacuolar signal peptide, were found. These results enabled us to identify sequences with putatively modified vacuole-targeting abilities. We found additional sequence variants using partial amplicons. We estimated that the minimum number of gene copies in the diploid genome of the investigated cultivar was fourteen. We obtained similar results for another three cultivars, which differed in bolting type and place of origin. The further identification of high degree of polymorphisms in the intron regions allowed us to develop a specific polymerase chain reaction assay capable to capture intron length polymorphism (ILP). This assay was used to screen 131 additional accessions. Polymorphic data were used for cluster analysis, which separated the bolting and non-bolting garlic types and those with high cysteine-sulfoxide contents in a similar way as AFLP analysis in previous study. These newly developed markers can be further applied for the selection of desirable garlic genotypes. CONCLUSIONS: Detailed analysis of sequences confirmed multigenic nature of garlic alliinase. Intron and exon polymorphism analysis generated similar results as whole genome variability assessed previously by AFLP. Detected polymorphism is thus also associated with cysteine-sulphoxide content in individual genotypes. ILP markers capable to detect intron polymorphisms were newly developed. Developed markers could be applied in garlic breeding. Higher genetic variability found in bolting genotypes may indicates longer period of their sexual propagation in comparison with nonbolting genotypes.


Assuntos
Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Alho/genética , Alho/metabolismo , Família Multigênica , Polimorfismo Genético , Liases de Carbono-Enxofre/química , Análise por Conglomerados , Íntrons , Mutação , Análise de Sequência de DNA
11.
J Pediatr Gastroenterol Nutr ; 58(3): 320-4, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24126833

RESUMO

BACKGROUND: Interferon-γ release assay (IGRA) is widely used for screening of latent tuberculosis (TB) before and during biological therapy (BT). An indeterminate result of IGRA represents a limitation in the management of inflammatory bowel disease (IBD). Data on factors influencing IGRA results are scarce in children. The aim of the study was to identify factors influencing IGRA results in children with IBD. METHODS: Seventy-two children with IBD (59 Crohn disease, 11 ulcerative colitis, 2 IBD-unclassified) indicated for BT were tested for TB infection (history, TB skin test, chest radiograph, IGRA; QuantiFERON-TB Gold in tube [QFT]) and consecutively retested using QFT in 1-year intervals. RESULTS: We recorded 165 results of QFT (3% positive, 87% negative, and 10% indeterminate results). During follow-up we identified 4 conversions of negative QFT to positivity (3%) and 4 reversions (4%). Patients with indeterminate results of QFT had significantly lower actual weight-for-height z score (P = 0.022), higher platelet count (P = 0.00017), and lower levels of serum albumin (P = 0.015) compared with patients with positive or negative QFT. Indeterminate QFT was associated with corticosteroid treatment, BT, and disease activity, but not with treatment by immunomodulators. In a subanalysis of patients with Crohn disease alone, Pediatric Crohn's Disease Activity Index was identified as single independent risk factor for indeterminate results (P = 0.00037). CONCLUSIONS: Although corticosteroid treatment is traditionally considered to be the main risk factor for indeterminate results of IGRA, the disease activity of IBD has even more profound effects on the results.


Assuntos
Doenças Inflamatórias Intestinais/complicações , Testes de Liberação de Interferon-gama , Interferon gama/metabolismo , Tuberculose Latente/diagnóstico , Teste Tuberculínico , Adolescente , Corticosteroides/efeitos adversos , Corticosteroides/uso terapêutico , Peso Corporal , Criança , Colite Ulcerativa/complicações , Colite Ulcerativa/patologia , Doença de Crohn/complicações , Doença de Crohn/patologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/patologia , Tuberculose Latente/complicações , Tuberculose Latente/metabolismo , Masculino , Contagem de Plaquetas , Fatores de Risco , Albumina Sérica/metabolismo
12.
Clin Lab ; 60(12): 1993-2000, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25651733

RESUMO

BACKGROUND: Children with suspected bowel inflammation require an invasive endoscopic procedure, which is usually performed under general anesthesia. To improve the selection of candidates for endoscopy, fecal calprotectin level has been proposed as a noninvasive marker of intestinal inflammation. In the future, home testing is a likely option. Thus, the aim of this study was to affirm the association between bedside-measured fecal calprotectin concentration and histological and endoscopic findings in a panel of patients with suspected chronic bowel inflammation. METHODS: Stool samples and microscopic and macroscopic findings from 41 patients, who underwent ileocolonoscopy for suspicion of bowel inflammation, were consecutively obtained between April 2009 and December 2010. Stool samples were analyzed using the bedside fecal calprotectin enzyme-linked immunosorbent assay (Quantum Blue; Bühlmann, Laboratories AG, Switzerland). RESULTS: Fecal calprotectin levels were elevated in 18 children with bowel inflammation on endoscopy (median at the upper limit of undiluted samples, 300 µg/g) compared with 23 children without bowel inflammation (median, 105 µg/g; p < 0.00097). Similarly, the fecal calprotectin level was elevated in 25 children with positive histological findings as assessed by a pathologist (median, 300 µg/g) compared with 16 children without histological inflammation (median, 73 µg/g; p < 0.000014). Based on the optimal area under the curve, we calculated the cutoff fecal calprotectin level for bowel inflammation on endoscopy as 167 µg/g (area under the curve, 0.86; 95% confidence interval (CI), 0.81 - 0.92) and on histological examination as 280 µg/g (area under the curve, 0.78; 95% CI, 0.70 - 0.86). Fecal calprotectin level was more sensitive than endoscopy for diagnosis of microscopic bowel inflammation (p = 0.000014). CONCLUSIONS: Our results clearly show that even the bedside test for fecal calprotectin level, using the optimal cut-off value, is feasible enough in determining candidates for an endoscopic procedure in order to confirm bowel inflammation and is more tightly associated with histological findings than with endoscopic findings. Thus, the calprotectin level reflects histological activity, even in cases with normal endoscopic findings. The bedside test described herein is a sufficient screening method for this purpose.


Assuntos
Colo , Colonoscopia , Fezes/química , Íleo , Mediadores da Inflamação/análise , Doenças Inflamatórias Intestinais/diagnóstico , Complexo Antígeno L1 Leucocitário/análise , Sistemas Automatizados de Assistência Junto ao Leito , Adolescente , Fatores Etários , Área Sob a Curva , Biomarcadores/análise , Estudos de Casos e Controles , Criança , Pré-Escolar , Colo/química , Colo/imunologia , Colo/patologia , Estudos de Viabilidade , Feminino , Humanos , Íleo/química , Íleo/imunologia , Íleo/patologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Masculino , Valor Preditivo dos Testes , Curva ROC , Regulação para Cima
13.
J Clin Lab Anal ; 28(4): 255-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24577896

RESUMO

AIM: To develop and validate high-sensitive (hs) ELISA method for detection of adipophilin (adipose differentiation-related protein, ADRP) in human breast milk (BM) and to analyze adipophilin levels in BM during 12 months of lactation. METHODS: ADRP levels were determined using hsELISA method (Biovendor-Laboratory Medicine, Inc.) in colostrum (D0) and BM of 72 mothers was collected 1, 3, 6, and 12 months following delivery (M1, 3, 6, 12). RESULTS: ADRP was detectable in BM up to 12 months of lactation. Mean levels at D0 were 1.98 ± 0.12; M1, 2.83 ± 0.21; M3, 2.39 ± 0.17; M6, 2.57 ± 0.16; and at M12 3.25 ± 0.21 µg/ml. Significantly higher levels of ADRP were found in M1 and M12 when compared to D0 and in M12 when compared to M3 (overall P = 0.0001). No significant correlation was seen between ADRP levels in BM and adiponectin, body weight of infants, their birth length, body weight gain during the first year of life, or BMI of mothers before pregnancy. CONCLUSIONS: We developed and validated hsELISA for detection of ADRP in human BM. ADRP was detectable in human BM during the whole 12 months of lactation period and its levels were intraindividually well-conserved.


Assuntos
Colostro/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas de Membrana/metabolismo , Leite Humano/metabolismo , Feminino , Humanos , Lactação , Perilipina-2 , Gravidez , Fatores de Tempo
14.
ChemMedChem ; 19(11): e202400145, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38445366

RESUMO

The binding process of insulin to its transmembrane receptor entails a sophisticated interplay between two proteins, each possessing two binding sites. Given the difficulties associated with the use of insulin in the treatment of diabetes, despite its remarkable efficacy, there is interest in smaller and more stable compounds than the native hormone that would effectively activate the receptor. Our study adopts a strategy focused on synthesizing extensive combinatorial libraries of bipodal compounds consisting of two distinct peptides linked to a molecular scaffold. These constructs, evaluated in a resin bead-bound format, were designed to assess their binding to the insulin receptor. Despite notable nonspecific binding, our approach successfully generated and tested millions of compounds. Rigorous evaluations via flow cytometry and specific antibodies revealed peptide sequences with specific interactions at either receptor binding Site 1 or 2. Notably, these sequences bear similarity to peptides discovered through phage display by other researchers. This convergence of chemical and biological methods underscores nature's beauty, revealing general principles in peptide binding to the insulin receptor. Overall, our study deepens the understanding of molecular interactions in ligand binding to the insulin receptor, highlighting the challenges of targeting large proteins with small synthetic peptides.


Assuntos
Técnicas de Química Combinatória , Receptor de Insulina , Receptor de Insulina/metabolismo , Receptor de Insulina/química , Humanos , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/síntese química , Sítios de Ligação , Biblioteca de Peptídeos , Ligantes , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/síntese química , Estrutura Molecular , Ligação Proteica , Insulina/metabolismo , Insulina/química
15.
Adv Mater ; 36(5): e2308965, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994248

RESUMO

The management of diabetes in a manner offering autonomous insulin therapy responsive to glucose-directed need, and moreover with a dosing schedule amenable to facile administration, remains an ongoing goal to improve the standard of care. While basal insulins with reduced dosing frequency, even once-weekly administration, are on the horizon, there is still no approved therapy that offers glucose-responsive insulin function. Herein, a nanoscale complex combining both electrostatic- and dynamic-covalent interactions between a synthetic dendrimer carrier and an insulin analogue modified with a high-affinity glucose-binding motif yields an injectable insulin depot affording both glucose-directed and long-lasting insulin availability. Following a single injection, it is even possible to control blood glucose for at least one week in diabetic swine subjected to daily oral glucose challenges. Measurements of serum insulin concentration in response to challenge show increases in insulin corresponding to elevated blood glucose levels, an uncommon finding even in preclinical work on glucose-responsive insulin. Accordingly, the subcutaneous nanocomplex that results from combining electrostatic- and dynamic-covalent interactions between a modified insulin and a synthetic dendrimer carrier affords a glucose-responsive insulin depot for week-long control following a single routine injection.


Assuntos
Dendrímeros , Diabetes Mellitus , Suínos , Animais , Camundongos , Insulina , Glucose , Glicemia
16.
Pediatr Pulmonol ; 58(3): 980-982, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36510661

RESUMO

We report the first described case of pulmonary tularaemia in the pediatric patient receiving infliximab for ulcerative colitis. We highlight the importance of considering Francisella tularensis in diagnostically challenging cases of persistent respiratory symptoms to facilitate early diagnosis and adequate therapy. The TCR-γδ + DN T cells are gaining important role in clinical practice. Polymerase chain reaction assays and serology guarantee early recognition.


Assuntos
Francisella tularensis , Doenças Inflamatórias Intestinais , Tularemia , Adolescente , Criança , Feminino , Humanos , Francisella tularensis/genética , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/efeitos adversos , Reação em Cadeia da Polimerase , Tularemia/diagnóstico , Tularemia/tratamento farmacológico
17.
Int J Pept Res Ther ; 29(2): 33, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891560

RESUMO

Insulin-like growth factor 1 (IGF-1) and its IGF-1 receptor (IGF-1R) belong to an important biological system that is involved in the regulation of normal growth, but that has also been recognized as playing a role in cancer. IGF-1R antagonists could be interesting for the testing of their potential antiproliferative properties as an alternative to IGF-1R tyrosine-kinase inhibitors or anti-IGF-1R monoclonal antibodies. In this study, we were inspired by the successful development of insulin dimers capable of antagonizing insulin effects on the insulin receptor (IR) by simultaneous binding to two separated binding sites and by blocking structural rearrangement of the IR. We designed and produced in Escherichia coli three different IGF-1 dimers in which IGF-1 monomers are interlinked through their N- and C-termini, with linkers having 8, 15 or 25 amino acids. We found that the recombinant products were susceptible to the formation of misfolded or reduced variants, but that some of them were able to bind IGF-1R in low nanomolar affinities and all of them activate IGF-1R proportionally to their binding affinities. Overall, our work can be considered as a pilot study that, although it did not lead to the discovery of new IGF-1R antagonists, explored the possibility of recombinant production of IGF-1 dimers and led to the preparation of active compounds. This work could inspire further studies dealing, for example, with the preparation of IGF-1 conjugates with specific proteins for the study of the hormone and its receptor or for therapeutic applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s10989-023-10499-1.

18.
Crohns Colitis 360 ; 5(4): otad040, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38028954

RESUMO

Background: A subcutaneous formulation of infliximab (IFX-SC) approved to treat patients with inflammatory bowel disease may offer improved efficacy versus intravenous infliximab. Methods: Patients with refractory Crohn's disease (CD, n = 32) previously treated unsuccessfully with at least 2 biologics were treated with IFX-SC and followed from baseline at Week 0 (W0) to Week 30 (W30). The study's primary endpoint was the treatment's persistence at W30, while secondary goals included the analysis of serum infliximab trough levels (TL IFX), dynamics of anti-IFX antibodies (ATIs), and clinical, serum and fecal markers of CD activity during IFX-SC treatment. Results: Midterm treatment persistence with the continuation of treatment after W30 was 53%. TL IFX median values showed rapid, significant upward dynamics and exceeded 15.5 µg/mL at W30, whereas median ATI levels significantly declined. Among ATI-negative patients at W0 (n = 15), only one showed IFX immunogenicity with newly developed ATIs at W30. Among ATI-positive patients at W0, ATI seroconversion from ATI-positive to ATI-negative status was observed in 10 of 17 patients (58.8%). Patients who had continued IFX-SC treatment at W30 showed significant decreases in C-reactive protein (P = .0341), fecal calprotectin (P = .0002), and Harvey-Bradshaw index (P = .0029) since W0. Conclusions: Patients with refractory CD previously treated with at least 2 biologics exhibited clinically relevant improvement with IFX-SC, which showed less immunogenic potential than IFX-IV and highly stable TL IFX.

19.
Clin Transl Gastroenterol ; 13(5): e00490, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363628

RESUMO

INTRODUCTION: Two antitumor necrosis factor therapies (infliximab [IFX] and adalimumab [ADA]) have been approved for the treatment of pediatric Crohn's disease (CD) but have not been compared in head-to-head trials. The aim of this study was to compare the efficacy and safety of ADA and IFX by propensity score matching in a prospective cohort of pediatric patients with luminal CD and at least a 24-month follow-up. METHODS: Among 100 patients, 75 met the inclusion criteria, and 62 were matched by propensity score. We evaluated time to treatment escalation as the primary outcome and primary nonresponse, predictors of treatment escalation and relapse, serious adverse events, pharmacokinetics, and effect of concomitant immunomodulators as secondary outcomes. RESULTS: There was no difference between ADA and IFX in time to treatment escalation (HR = 0.63 [95% CI 0.31-1.28] P = 0.20), primary nonresponse (P = 0.95), or serious adverse events. The median (interquartile range) trough levels at the primary outcome were 14.05 (10.88-15.40) and 6.15 (2.08-6.58) µg/mL in the ADA and IFX groups, respectively. On a multivariate analysis, the combination of anti-Saccharomyces cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity was a strong independent predictor of treatment escalation (HR 5.19, [95% CI 2.41-11.18], P < 0.0001). The simple endoscopic score for CD, L3 disease phenotype, and use of concomitant immunomodulators for at least the first 6 months revealed a trend toward significance on a univariate analysis. DISCUSSION: Propensity score matching did not reveal substantial differences in efficacy or safety between ADA and IFX. The anti-S. cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity combination is a strong predictor of treatment escalation.


Assuntos
Doença de Crohn , Adalimumab/efeitos adversos , Anticorpos Anticitoplasma de Neutrófilos , Criança , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Humanos , Fatores Imunológicos , Infliximab/uso terapêutico , Pontuação de Propensão , Estudos Prospectivos , Resultado do Tratamento
20.
J Crohns Colitis ; 16(9): 1347-1353, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-35358307

RESUMO

BACKGROUND AND AIMS: Knowledge on the immunogenicity of anti-SARS-CoV-2 vaccines in inflammatory bowel disease [IBD] patients is limited. Therefore, SARS-CoV-2-specific T-cell responses and antibodies were analysed in 60 IBD vaccine recipients and 30 controls. METHODS: SARS-CoV-2 IgG antibodies against the viral spike protein were measured at baseline and at 8 and 26 weeks after the second vaccine dose. SARS-CoV-2 IgG antibodies against the nucleocapsid antigens were measured at week 26. A SARS-CoV-2 interferon-gamma released assay [IGRA] was performed in all vaccinees at week 26. RESULTS: At weeks 0 and 8, no differences were found in anti-spike antibodies between cohorts. At week 26, the decrease in antibody levels was more significant in the IBD cohort compared to the healthy cohort, and anti-nucleocapsid antibodies were not detected in either group. At week 26, 16 of 90 [18%] vaccinated individuals had a negative IGRA test result, seven of 90 [8%] were borderline and 67 [74%] had a positive IGRA result; 22 of the 23 individuals with negative or borderline IGRA results belonged to the IBD cohort. However, the overall functional ability of T-lymphocytes to produce interferon-gamma after the unspecific mitogen stimulation was lower in IBD patients. In vaccinated individuals with low or borderline IGRA, treatment with tumour necrosis factor-alpha inhibitors was the most frequent. In individuals with a significant drop in anti-spike antibody levels, plasmatic interferon-gamma concentrations after the specific SARS-CoV-2 stimulation were also insufficient. CONCLUSIONS: Simple humoral and cellular post-vaccination monitoring is advisable in IBD patients so that repeated vaccine doses may be scheduled.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Vacinas Virais , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunidade Humoral , Imunoglobulina G , Doenças Inflamatórias Intestinais/tratamento farmacológico , Interferon gama , SARS-CoV-2 , Vacinação
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