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1.
ACS Appl Bio Mater ; 5(2): 471-482, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35045699

RESUMO

Desferrioxamine (DFO) upregulates HIF-1α and stimulates expression of vascular endothelial growth factor (VEGF), thereby accelerating neovascularization. As DFO acts primarily upon surrounding vein endothelial cells to stimulate angiogenesis, the angiogenic efficacy of DFO could be reduced in severely injured tissues lacking a sufficient number of vein endothelial cells. We hypothesized that combined administration of DFO and vein endothelial cells is a promising tissue engineering approach for promoting neovascularization. In this study, we evaluated the applicability of this approach using injectable, biocompatible, biodegradable nanocomposite gels consisting of poly(dl-lactide-co-glycolide)-b-polyethylene glycol-b-poly(dl-lactide-co-glycolide) (PLGA-PEG-PLGA) copolymers and clay nanoparticle LAPONITE. The nanocomposites exhibited irreversible thermo-gelation in the presence of DFO, and the mechanical strength was strongly affected by the amount of DFO. The storage moduli of the gels increased with increasing amount of DFO. These results indicate that the interaction between DFO and LAPONITE works as physical cross-linking points and facilitates the formation of the gel network. The nanocomposite gels achieved sustained slow release of DFO due to interactions between DFO and LAPONITE. Human umbilical vein endothelial cells (HUVECs) cultured on DFO-loaded nanocomposite gels exhibited a higher degree of vascular tube formation than cells cultured on nanocomposite gels without DFO. Moreover, the number of branching points and the diameter of the blood vessels regenerated in the gels significantly increased with increasing DFO amount, indicating that DFO released from the gels facilitates vascular tube-forming capacity. As a proof of concept, we demonstrate that the combined administration of DFO and vein endothelial cells using nanocomposite gels promotes greater angiogenesis than DFO administration alone using the same gels by in vivo experiments, confirming the validity of our hypothesis. Considering the multiple advantages of nanocomposite gels with regard to potential vascularization capacity, certain biocompatibility, biodegradability, and injectable cell- and drug-delivery capacity, we concluded that the nanocomposite gels have potential utility as scaffolding biomaterials for vascularization in tissue engineering applications.


Assuntos
Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hidrogéis/farmacologia , Nanogéis , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Biomacromolecules ; 22(10): 4217-4227, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34546743

RESUMO

Systemic enzyme-prodrug therapy (EPT) using nanofactories, nanoparticles encapsulating prodrug-activating enzymes, is a promising concept for anticancer therapy. However, systemic delivery systems can be problematic. As nanofactories are typically carried by the blood circulation to tissues throughout the body, conversion of anticancer drugs in normal tissues can cause severe side effects. To overcome this problem, we developed a novel focal EPT approach utilizing nanocomposite hydrogels composed of a poly(dl-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(dl-lactide-co-glycolide) (PLGA-PEG-PLGA) copolymer, LAPONITE, and ß-galactosidase (ß-gal). The nanocomposite gels can be easily injected locally, and the inherent enzyme activity of ß-gal can be preserved long-term. Prodrug 5-FU-ß-gal readily permeated into the interior space of gels and was converted into the active anticancer drug 5-FU. Importantly, a single local injection of nanocomposite gels and prodrug 5-FU-ß-gal provided long-lasting antitumor activity in vivo without observable side effects, demonstrating the potential utility of injectable biocatalytic hydrogel factories for novel focal EPT systems.


Assuntos
Neoplasias , Pró-Fármacos , Humanos , Hidrogéis , Nanogéis , Polietilenoglicóis
3.
Biomater Sci ; 8(2): 577-585, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31872195

RESUMO

Hypersialylation is the aberrant expression of sialic acid in cell surface glycans and is pervasive in cancer cells. Recent studies have shown that hypersialylation provides a microenvironment conducive to cancer progression, mediated by the interaction between sialic acid and sialic acid-binding receptors. Therefore, a technique to block the interaction between the overexpressed sialic acid on cancer cell surfaces and its receptors is a promising approach to develop new cancer therapies. We focused on hydrogels as an artificial barrier to block this interaction and present here the development of a novel technique for selectively covalently binding a thin hydrogel barrier on sialic acid residues on cancer cell surfaces. This technique effectively inhibited cancer cell adhesion, motility and growth, caused cancer cell death in vitro, and completely suppressed tumor growth in vivo, thereby clearly demonstrating a potent antitumor effect.


Assuntos
Antineoplásicos/farmacologia , Membrana Celular/química , Hidrogéis/farmacologia , Ácido N-Acetilneuramínico/farmacologia , Antineoplásicos/química , Configuração de Carboidratos , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrogéis/química , Células MCF-7 , Ácido N-Acetilneuramínico/química
4.
PLoS One ; 12(12): e0190102, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29267348

RESUMO

Population aging is a global phenomenon, and choosing appropriate medical care for the elderly is critical. Polypharmacy is suspected to increase the risk of adverse events (AEs) in older patients. We examined the AE profiles associated with polypharmacy and aging using the Japanese Adverse Drug Event Report (JADER) database. We attempted to mitigate the effect of patient-related factors using a multiple-logistic regression technique and data subsetting. We selected case reports for AEs as specified in the Medical Dictionary for Regulatory Activities (MedDRA). The association between polypharmacy and "renal disorder" or "hepatic disorder" was evaluated using reporting odds ratio (ROR) and adjusted for covariates using multiple-logistic regression. For renal disorder, advanced polypharmacy showed higher adjusted RORs, because the value of administered drugs group [1.82 (1.76-1.88), ≥ 10] was higher than that of the number of administered drugs group [1.27 (1.24-1.31), 5-9]. The lower limit of the 95% confidence interval (CI) of adjusted ROR for age (≥ 60 years) was > 1 for renal disorder. For hepatic disorder, the adjusted RORs were as follows: 1.17 (1.14-1.20) for the number of administered drugs group (5-9) and 1.14 (1.11-1.18) for the number of administered drugs group (≥ 10). The adjusted RORs of hepatic disorder compared to those of renal disorder had lower adjusted RORs related to the increase in the number of administered drugs. Therefore, elderly individuals should be closely monitored for the occurrence of renal disorder when they are subjected to polypharmacy. This approach might apply to the simultaneous evaluation of the AE risk of polypharmacy and aging.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Polimedicação , Idoso , Feminino , Humanos , Japão , Masculino
5.
Yakugaku Zasshi ; 136(3): 507-15, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-26935094

RESUMO

The Japanese Ministry of Health, Labor, and Welfare lists hand-foot syndrome as a serious adverse drug event. Therefore, we evaluated its association with anticancer drug therapy using case reports in the Japanese Adverse Drug Event Report (JADER) and the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). In addition, we calculated the reporting odds ratio (ROR) of anticancer drugs potentially associated with hand-foot syndrome, and applied the Weibull shape parameter to time-to-event data from JADER. We found that JADER contained 338224 reports from April 2004 to November 2014, while FAERS contained 5821354 reports from January 2004 to June 2014. In JADER, the RORs [95% confidence interval (CI)] of hand-foot syndrome for capecitabine, tegafur-gimeracil-oteracil, fluorouracil, sorafenib, and regorafenib were 63.60 (95%CI, 56.19-71.99), 1.30 (95%CI, 0.89-1.89), 0.48 (95%CI, 0.30-0.77), 26.10 (95%CI, 22.86-29.80), and 133.27 (95%CI, 112.85-157.39), respectively. Adverse event symptoms of hand-foot syndrome were observed with most anticancer drugs, which carry warnings of the propensity to cause these effects in their drug information literature. The time-to-event analysis using the Weibull shape parameter revealed differences in the time-dependency of the adverse events of each drug. Therefore, anticancer drugs should be used carefully in clinical practice, and patients may require careful monitoring for symptoms of hand-foot syndrome.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Antineoplásicos/efeitos adversos , Conjuntos de Dados como Assunto/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Síndrome Mão-Pé/epidemiologia , Síndrome Mão-Pé/etiologia , Síndrome Mão-Pé/prevenção & controle , Humanos , Japão/epidemiologia , Fatores de Tempo , Estados Unidos , United States Food and Drug Administration
6.
Artigo em Inglês | MEDLINE | ID: mdl-26819726

RESUMO

BACKGROUND: Antipsychotics are potent dopamine antagonists used to treat schizophrenia and bipolar disorder. The aim of this study was to evaluate the relationship between antipsychotic drugs and adverse hyperglycemic events using the FDA Adverse Event Reporting System (FAERS) database. In particular, we focused on adverse hyperglycemic events associated with atypical antipsychotic use, which are major concerns. FINDINGS: We analyzed reports of adverse hyperglycemic events associated with 26 antipsychotic drugs in the FAERS database from January 2004 to March 2013. The Standardized Medical Dictionary for Regulatory Activities Queries (SMQ) preferred terms (PTs) was used to identify adverse hyperglycemic events. The number of adverse hyperglycemic reports for the top eight antipsychotic drugs, quetiapine, olanzapine, risperidone, aripiprazole, haloperidol, clozapine, prochlorperazine, and chlorpromazine was 12,471 (28.9%), 8,423 (37.9%), 5,968 (27.0%), 4,045 (23.7%), 3,445 (31.5%), 2,614 (14.3%), 1,800 (19.8%), and 1,003 (35.7%), respectively. The reporting ratio increased with co-administration of multiple antipsychotic drugs. For example, adverse hyperglycemic events represented 21.6% of reports for quetiapine monotherapy, 39.9% for two-drug polypharmacy, and 66.3% for three-drug polypharmacy. CONCLUSION: Antipsychotic drug polypharmacy may influence signal strength, and may be associated with hyperglycemia. After considering the causality restraints of the current analysis, further robust epidemiological studies are recommended.

7.
Artigo em Inglês | MEDLINE | ID: mdl-26819745

RESUMO

BACKGROUND: Bisphosphonates (BPs) are potent antiresorptive agents used to treat osteoporosis and the complications associated with malignant bone metastasis. The aim of this study was to evaluate the incidence of bisphosphonate-related osteonecrosis of the jaw (BRONJ) using the Japanese Adverse Drug Event Report (JADER) database. In particular, we focused on the time-to-onset profile of BRONJ. FINDINGS: We analyzed reports of BRONJ in the JADER database and calculated the reporting odds ratio (ROR) of BPs potentially associated with BRONJ. We applied the weibull shape parameter to time-to-event data in JADER. The drugs selected for this investigation were seven BPs approved in Japan (alendronate [intraveneous, I.V.], pamidronate, and zoledronate as I.V. BPs; and alendronate (oral), etidronate, minodronate, and risedronate as oral BPs). We analyzed reports of BRONJ events associated with BPs in the JADER database from April 2004 to November 2014. The median value of BRONJ cases caused by alendronate (I.V.), pamidronate, zoledronate, alendronate (oral), etidronate, minodronate, and risedronate were 1342, 812, 486, 863, 1461, 432, and 730 days, respectively. The lower 95 % confidence interval of the Weibull-shape parameter ß for I.V. BPs (pamidronate and zoledronate) exceeded 1. The risk of BRONJ with I.V. BPs increased over time. CONCLUSION: Thus, the incidence of BRONJ with BP treatment should be closely monitored for a 3-year period. Further studies are required to draw conclusions, and we believe that this information about BRONJ induced by BPs will prove beneficial to patients and pharmacists.

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