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1.
J Pharm Sci ; 113(3): 718-724, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37690778

RESUMO

Triggerable coatings, such as pH-responsive polymethacrylate copolymers, can be used to protect the active pharmaceutical ingredients contained within oral solid dosage forms from the acidic gastric environment and to facilitate drug delivery directly to the intestine. However, gastrointestinal pH can be highly variable, which can reduce delivery efficiency when using pH-responsive drug delivery technologies. We hypothesized that biomaterials susceptible to proteolysis could be used in combination with other triggerable polymers to develop novel enteric coatings. Bioinformatic analysis suggested that silk fibroin is selectively degradable by enzymes in the small intestine, including chymotrypsin, but resilient to gastric pepsin. Based on the analysis, we developed a silk fibroin-polymethacrylate copolymer coating for oral dosage forms. In vitro and in vivo studies demonstrated that capsules coated with this novel silk fibroin formulation enable pancreatin-dependent drug release. We believe that this novel formulation and extensions thereof have the potential to produce more effective and personalized oral drug delivery systems for vulnerable populations including patients that have impaired and highly variable intestinal physiology.


Assuntos
Fibroínas , Humanos , Pancreatina , Sistemas de Liberação de Medicamentos , Ácidos Polimetacrílicos , Polímeros , Seda
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2491-2494, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36085797

RESUMO

More than two decades ago it was discovered that nitric oxide (NO) concentrations in gas aspirated during colonoscopy were more than 100 times higher in patients diagnosed with Ulcerative Colitis (UC) than controls. While this provides a diagnostic opportunity, it has not been possible to perform in situ detection of NO via a non-invasive manner. This work presents the feasibility of in situ detection of NO by means of a capsule-like electrochemical gas sensor. Our in vivo results in a large animal model of intestinal inflammation show that NO can be directly detected at the site of inflammation and that it quickly dissipates to surrounding tissues, demonstrating the importance of in situ detection.


Assuntos
Inflamação , Óxido Nítrico , Animais , Biomarcadores , Colonoscopia , Modelos Animais de Doenças , Inflamação/diagnóstico
3.
Sci Transl Med ; 14(651): eabl4135, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35767653

RESUMO

Carbon monoxide (CO) has long been considered a toxic gas but is now a recognized bioactive gasotransmitter with potent immunomodulatory effects. Although inhaled CO is currently under investigation for use in patients with lung disease, this mode of administration can present clinical challenges. The capacity to deliver CO directly and safely to the gastrointestinal (GI) tract could transform the management of diseases affecting the GI mucosa such as inflammatory bowel disease or radiation injury. To address this unmet need, inspired by molecular gastronomy techniques, we have developed a family of gas-entrapping materials (GEMs) for delivery of CO to the GI tract. We show highly tunable and potent delivery of CO, achieving clinically relevant CO concentrations in vivo in rodent and swine models. To support the potential range of applications of foam GEMs, we evaluated the system in three distinct disease models. We show that a GEM containing CO dose-dependently reduced acetaminophen-induced hepatocellular injury, dampened colitis-associated inflammation and oxidative tissue injury, and mitigated radiation-induced gut epithelial damage in rodents. Collectively, foam GEMs have potential paradigm-shifting implications for the safe therapeutic use of CO across a range of indications.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Monóxido de Carbono/uso terapêutico , Colite/tratamento farmacológico , Gases , Inflamação/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Suínos
4.
J Control Release ; 343: 31-42, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34998917

RESUMO

Glycemic control through titration of insulin dosing remains the mainstay of diabetes mellitus treatment. Insulin therapy is generally divided into dosing with long- and short-acting insulin, where long-acting insulin provides basal coverage and short-acting insulin supports glycemic excursions associated with eating. The dosing of short-acting insulin often involves several steps for the user including blood glucose measurement and integration of potential carbohydrate loads to inform safe and appropriate dosing. The significant burden placed on the user for blood glucose measurement and effective carbohydrate counting can manifest in substantial effects on adherence. Through the application of computer vision, we have developed a smartphone-based system that is able to detect the carbohydrate load of food by simply taking a single image of the food and converting that information into a required insulin dose by incorporating a blood glucose measurement. Moreover, we report the development of comprehensive all-in-one insulin delivery systems that streamline all operations that peripheral devices require for safe insulin administration, which in turn significantly reduces the complexity and time required for titration of insulin. The development of an autonomous system that supports maximum ease and accuracy of insulin dosing will transform our ability to more effectively support patients with diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Insulina , Glicemia , Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Insulina de Ação Curta/uso terapêutico
5.
Adv Sci (Weinh) ; 8(24): e2102861, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34713599

RESUMO

Continuous monitoring in the intensive care setting has transformed the capacity to rapidly respond with interventions for patients in extremis. Noninvasive monitoring has generally been limited to transdermal or intravascular systems coupled to transducers including oxygen saturation or pressure. Here it is hypothesized that gastric fluid (GF) and gases, accessible through nasogastric (NG) tubes, commonly found in intensive care settings, can provide continuous access to a broad range of biomarkers. A broad characterization of biomarkers in swine GF coupled to time-matched serum is conducted . The relationship and kinetics of GF-derived analyte level dynamics is established by correlating these to serum levels in an acute renal failure and an inducible stress model performed in swine. The ability to monitor ketone levels and an inhaled anaesthetic agent (isoflurane) in vivo is demonstrated with novel NG-compatible sensor systems in swine. Gastric access remains a main stay in the care of the critically ill patient, and here the potential is established to harness this establishes route for analyte evaluation for clinical management.


Assuntos
Injúria Renal Aguda/metabolismo , Anestésicos Inalatórios/metabolismo , Suco Gástrico/metabolismo , Isoflurano/metabolismo , Monitorização Fisiológica/métodos , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Intubação Gastrointestinal , Cetonas/metabolismo , Estômago/metabolismo , Suínos
6.
Pharm Res ; 37(12): 234, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33123783

RESUMO

PURPOSE: A multitude of different versions of the same medication with different inactive ingredients are currently available. It has not been quantified how this has evolved historically. Furthermore, it is unknown whether healthcare professionals consider the inactive ingredient portion when prescribing medications to patients. METHODS: We used data mining to track the number of available formulations for the same medication over time and correlate the number of available versions in 2019 to the number of manufacturers, the years since first approval, and the number of prescriptions. A focused survey among healthcare professionals was conducted to query their consideration of the inactive ingredient portion of a medication when writing prescriptions. RESULTS: The number of available versions of a single medication have dramatically increased in the last 40 years. The number of available, different versions of medications are largely determined by the number of manufacturers producing this medication. Healthcare providers commonly do not consider the inactive ingredient portion when prescribing a medication. CONCLUSIONS: A multitude of available versions of the same medications provides a potentially under-recognized opportunity to prescribe the most suitable formulation to a patient as a step towards personalized medicine and mitigate potential adverse events from inactive ingredients.


Assuntos
Competência Clínica/estatística & dados numéricos , Composição de Medicamentos/história , Excipientes Farmacêuticos/efeitos adversos , Medicamentos sob Prescrição/química , Prescrições de Medicamentos , História do Século XX , História do Século XXI , Humanos , Excipientes Farmacêuticos/química , Excipientes Farmacêuticos/história , Medicamentos sob Prescrição/efeitos adversos , Medicamentos sob Prescrição/história , Inquéritos e Questionários/estatística & dados numéricos
7.
Proc Natl Acad Sci U S A ; 117(22): 11987-11994, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32424082

RESUMO

Chronic hepatitis C virus (HCV) infection is a leading cause of cirrhosis worldwide and kills more Americans than 59 other infections, including HIV and tuberculosis, combined. While direct-acting antiviral (DAA) treatments are effective, limited uptake of therapy, particularly in high-risk groups, remains a substantial barrier to eliminating HCV. We developed a long-acting DAA system (LA-DAAS) capable of prolonged dosing and explored its cost-effectiveness. We designed a retrievable coil-shaped LA-DAAS compatible with nasogastric tube administration and the capacity to encapsulate and release gram levels of drugs while resident in the stomach. We formulated DAAs in drug-polymer pills and studied the release kinetics for 1 mo in vitro and in vivo in a swine model. The LA-DAAS was equipped with ethanol and temperature sensors linked via Bluetooth to a phone application to provide patient engagement. We then performed a cost-effectiveness analysis comparing LA-DAAS to DAA alone in various patient groups, including people who inject drugs. Tunable release kinetics of DAAs was enabled for 1 mo with drug-polymer pills in vitro, and the LA-DAAS safely and successfully provided at least month-long release of sofosbuvir in vivo. Temperature and alcohol sensors could interface with external sources for at least 1 mo. The LA-DAAS was cost-effective compared to DAA therapy alone in all groups considered (base case incremental cost-effectiveness ratio $39,800). We believe that the LA-DAA system can provide a cost-effective and patient-centric method for HCV treatment, including in high-risk populations who are currently undertreated.


Assuntos
Antivirais/administração & dosagem , Sistemas de Liberação de Medicamentos , Hepatite C Crônica/tratamento farmacológico , Animais , Antivirais/farmacocinética , Benzimidazóis/administração & dosagem , Benzimidazóis/farmacocinética , Carbamatos , Análise Custo-Benefício , Modelos Animais de Doenças , Portadores de Fármacos/farmacocinética , Sistemas de Liberação de Medicamentos/economia , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Fluorenos/administração & dosagem , Fluorenos/farmacocinética , Hepacivirus/efeitos dos fármacos , Imidazóis/administração & dosagem , Imidazóis/farmacocinética , Cirrose Hepática/tratamento farmacológico , Modelos Animais , Pirrolidinas , Ribavirina/administração & dosagem , Ribavirina/farmacocinética , Sofosbuvir/administração & dosagem , Sofosbuvir/farmacocinética , Suínos , Valina/análogos & derivados
8.
Crit Care Med ; 48(4): e299-e307, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32205620

RESUMO

OBJECTIVES: Neurologic damage following cardiac arrest remains a major burden for modern resuscitation medicine. Cardiopulmonary resuscitation with extracorporeal circulatory support holds the potential to reduce morbidity and mortality. Furthermore, the endogenous gasotransmitter carbon monoxide attracts attention in reducing cerebral injury. We hypothesize that extracorporeal resuscitation with additional carbon monoxide application reduces neurologic damage. DESIGN: Randomized, controlled animal study. SETTING: University research laboratory. SUBJECTS: Landrace-hybrid pigs. INTERVENTIONS: In a porcine model, carbon monoxide was added using a novel extracorporeal releasing system after resuscitation from cardiac arrest. MEASUREMENTS AND MAIN RESULTS: As markers of cerebral function, neuromonitoring modalities (somatosensory-evoked potentials, cerebral oximetry, and transcranial Doppler ultrasound) were used. Histopathologic damage and molecular markers (caspase-3 activity and heme oxygenase-1 expression) were analyzed. Cerebral oximetry showed fast rise in regional oxygen saturation after carbon monoxide treatment at 0.5 hours compared with extracorporeal resuscitation alone (regional cerebral oxygen saturation, 73% ± 3% vs 52% ± 8%; p < 0.05). Median nerve somatosensory-evoked potentials showed improved activity upon carbon monoxide treatment, whereas post-cardiac arrest cerebral perfusion differences were diminished. Histopathologic damage scores were reduced compared with customary resuscitation strategies (hippocampus: sham, 0.4 ± 0.2; cardiopulmonary resuscitation, 1.7 ± 0.4; extracorporeal cardiopulmonary resuscitation, 2.3 ± 0.2; extracorporeal cardiopulmonary resuscitation with carbon monoxide application [CO-E-CPR], 0.9 ± 0.3; p < 0.05). Furthermore, ionized calcium-binding adaptor molecule 1 staining revealed reduced damage patterns upon carbon monoxide treatment. Caspase-3 activity (cardiopulmonary resuscitation, 426 ± 169 pg/mL; extracorporeal cardiopulmonary resuscitation, 240 ± 61 pg/mL; CO-E-CPR, 89 ± 26 pg/mL; p < 0.05) and heme oxygenase-1 (sham, 1 ± 0.1; cardiopulmonary resuscitation, 2.5 ± 0.4; extracorporeal cardiopulmonary resuscitation, 2.4 ± 0.2; CO-E-CPR, 1.4 ± 0.2; p < 0.05) expression were reduced after carbon monoxide exposure. CONCLUSIONS: Carbon monoxide application during extracorporeal resuscitation reduces injury patterns in neuromonitoring and decreases histopathologic cerebral damage by reducing apoptosis. This may lay the basis for further clinical translation of this highly salutary substance.


Assuntos
Encéfalo , Monóxido de Carbono , Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca , Animais , Masculino , Encéfalo/irrigação sanguínea , Monóxido de Carbono/metabolismo , Monóxido de Carbono/uso terapêutico , Reanimação Cardiopulmonar/métodos , Circulação Cerebrovascular/fisiologia , Oxigenação por Membrana Extracorpórea/métodos , Parada Cardíaca/terapia , Suínos , Resultado do Tratamento
9.
Clin Transl Gastroenterol ; 11(12): e00229, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33512801

RESUMO

INTRODUCTION: Bile acids, such as chenodeoxycholic acid, play an important role in digestion but are also involved in intestinal motility, fluid homeostasis, and humoral activity. Colonic delivery of sodium chenodeoxycholate (CDC) has demonstrated clinical efficacy in treating irritable bowel syndrome with constipation but was associated with a high frequency of abdominal pain. We hypothesized that these adverse effects were triggered by local super-physiological CDC levels caused by an unfavorable pharmacokinetic profile of the delayed release formulation. METHODS: We developed novel release matrix systems based on hydroxypropyl methylcellulose (HPMC) for sustained release of CDC. These included standard HPMC formulations as well as bi-layered formulations to account for potential delivery failures due to low colonic fluid in constipated patients. We evaluated CDC release profiles in silico (pharmacokinetic modeling), in vitro and in vivo in swine (pharmacokinetics, rectal manometry). RESULTS: For the delayed release formulation in vitro release studies demonstrated pH triggered dose dumping which was associated with giant colonic contractions in vivo. Release from the bi-layered HPMC systems provided controlled release of CDC while minimizing the frequency of giant contractions and providing enhanced exposure as compared to standard HPMC formulations in vivo. DISCUSSION: Bi-phasic CDC release could help treat constipation while mitigating abdominal pain observed in previous clinical trials. Further studies are necessary to demonstrate the therapeutic potential of these systems in humans.


Assuntos
Ácido Quenodesoxicólico/administração & dosagem , Portadores de Fármacos/química , Derivados da Hipromelose/química , Animais , Ácido Quenodesoxicólico/farmacocinética , Colo/química , Colo/metabolismo , Simulação por Computador , Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/etiologia , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/química , Mucosa Intestinal/metabolismo , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/tratamento farmacológico , Modelos Animais , Modelos Biológicos , Peristaltismo/efeitos dos fármacos , Suínos
10.
Cardiovasc Res ; 116(1): 158-170, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30873524

RESUMO

AIMS: Heart disease of different aetiology remains the leading cause of cardiac arrest (CA). Despite efforts to improve the quality of cardiopulmonary resuscitation (CPR), subsequent myocardial and systemic damage after CA still present a major long-term burden. Low-dose carbon monoxide (CO) is known to exert protective effects in cardiovascular pathophysiology but clinical applications are challenged by unfavourable delivery modes. We tested the hypothesis that extracorporeal resuscitation (E-CPR) in combination with controlled fast onset CO delivery results in improved cardiac physiology and haemodynamics. Damage-associated molecular pattern (DAMP) signalling may be part of the molecular mechanism. METHODS AND RESULTS: In an established porcine model, E-CPR was performed. While E-CPR leads to similar results as compared to a conventional CPR strategy, CO delivery in combination with E-CPR demonstrated significant cardioprotection. Cardiac performance analysis using echocardiography and thermodilution techniques showed a CO-dependent improved cardiac function compared to severe myocardial dysfunction in CPR and E-CPR (left ventricular ejection fraction: Sham 49 ± 5; CPR 26 ± 2; E-CPR 25 ± 2; CO-E-CPR 31 ± 4; P < 0.05). While sublingual microcirculation was significantly compromised in CPR and E-CPR, CO delivery demonstrated a significant improvement in microvascular function (microvascular flow index: Sham 2.9 ± 0.1; CPR 2.2 ± 0.1; E-CPR 1.8 ± 0.1; CO-E-CPR 2.7 ± 0.1; P < 0.01). Histological and serological myocardial damage markers were significantly reduced (hsTroponin-T Sham 0.01 ± 0.001; CPR 1.9 ± 0.2; E-CPR 3.5 ± 1.2; CO-E-CPR 0.5 ± 0.2 ng/mL; P < 0.05). DAMP signalling was decreased ipse facto leading to influence of cardioprotective heat shock and cyclooxygenase response. CONCLUSIONS: CO treatment restores myocardial function and improves systemic macro- and microhaemodynamics in E-CPR through a reduction in DAMPs.


Assuntos
Monóxido de Carbono/farmacologia , Reanimação Cardiopulmonar , Oxigenação por Membrana Extracorpórea , Parada Cardíaca/terapia , Hemodinâmica/efeitos dos fármacos , Mucosa Bucal/irrigação sanguínea , Miócitos Cardíacos/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Alarminas/metabolismo , Animais , Modelos Animais de Doenças , Parada Cardíaca/sangue , Parada Cardíaca/patologia , Parada Cardíaca/fisiopatologia , Microcirculação/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Recuperação de Função Fisiológica , Transdução de Sinais , Sus scrofa , Fatores de Tempo
11.
Am J Physiol Renal Physiol ; 317(6): F1572-F1581, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31482730

RESUMO

Deleterious consequences like acute kidney injury frequently occur upon successful resuscitation from cardiac arrest. Extracorporeal life support is increasingly used to overcome high cardiac arrest mortality. Carbon monoxide (CO) is an endogenous gasotransmitter, capable of reducing renal injury. In our study, we hypothesized that addition of CO to extracorporeal resuscitation hampers severity of renal injury in a porcine model of cardiac arrest. Hypoxic cardiac arrest was induced in pigs. Animals were resuscitated using a conventional [cardiopulmonary resuscitation (CPR)], an extracorporeal (E-CPR), or a CO-assisted extracorporeal (CO-E-CPR) protocol. CO was applied using a membrane-controlled releasing system. Markers of renal injury were measured, and histopathological analyses were carried out. We investigated renal pathways involving inflammation as well as apoptotic cell death. No differences in serum neutrophil gelatinase-associated lipocalin (NGAL) were detected after CO treatment compared with Sham animals (Sham 71 ± 7 and CO-E-CPR 95 ± 6 ng/mL), while NGAL was increased in CPR and E-CPR groups (CPR 135 ± 11 and E-CPR 124 ± 5 ng/mL; P < 0.05). Evidence for histopathological damage was abrogated after CO application. CO increased renal heat shock protein 70 expression and reduced inducible cyclooxygenase 2 (CPR: 60 ± 8; E-CPR 56 ± 8; CO-E-CPR 31 ± 3 µg/mL; P < 0.05). Caspase 3 activity was decreased (CPR 1,469 ± 276; E-CPR 1,670 ± 225; CO-E-CPR 755 ± 83 pg/mL; P < 0.05). Furthermore, we found a reduction in renal inflammatory signaling upon CO treatment. Our data demonstrate improved renal function by extracorporeal CO treatment in a porcine model of cardiac arrest. CO reduced proinflammatory and proapoptotic signaling, characterizing beneficial aspects of a novel treatment option to overcome high mortality.


Assuntos
Monóxido de Carbono/uso terapêutico , Reanimação Cardiopulmonar/métodos , Circulação Extracorpórea/métodos , Parada Cardíaca/tratamento farmacológico , Inflamação/tratamento farmacológico , Nefropatias/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/sangue , Monóxido de Carbono/administração & dosagem , Parada Cardíaca/complicações , Parada Cardíaca/patologia , Inflamação/patologia , Nefropatias/etiologia , Nefropatias/patologia , Testes de Função Renal , Lipocalina-2/metabolismo , Suínos
12.
Sci Transl Med ; 11(483)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867322

RESUMO

Multigram drug depot systems for extended drug release could transform our capacity to effectively treat patients across a myriad of diseases. For example, tuberculosis (TB) requires multimonth courses of daily multigram doses for treatment. To address the challenge of prolonged dosing for regimens requiring multigram drug dosing, we developed a gastric resident system delivered through the nasogastric route that was capable of safely encapsulating and releasing grams of antibiotics over a period of weeks. Initial preclinical safety and drug release were demonstrated in a swine model with a panel of TB antibiotics. We anticipate multiple applications in the field of infectious diseases, as well as for other indications where multigram depots could impart meaningful benefits to patients, helping maximize adherence to their medication.


Assuntos
Antituberculosos/uso terapêutico , Sistemas de Liberação de Medicamentos , Estômago/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Antituberculosos/farmacologia , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Doxiciclina/uso terapêutico , Sistemas de Liberação de Medicamentos/economia , Liberação Controlada de Fármacos , Humanos , Suínos
13.
Sci Transl Med ; 11(483)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30867323

RESUMO

Oral forms of medications contain "inactive" ingredients to enhance their physical properties. Using data analytics, we characterized the abundance and complexity of inactive ingredients in approved medications. A majority of medications contain ingredients that could cause adverse reactions, underscoring the need to maximize the tolerability and safety of medications and their inactive ingredients.


Assuntos
Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/análise , Administração Oral , Animais , Composição de Medicamentos , Excipientes/efeitos adversos , Humanos
14.
Nat Commun ; 10(1): 493, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700712

RESUMO

Devices that interact with living organisms are typically made of metals, silicon, ceramics, and plastics. Implantation of such devices for long-term monitoring or treatment generally requires invasive procedures. Hydrogels offer new opportunities for human-machine interactions due to their superior mechanical compliance and biocompatibility. Additionally, oral administration, coupled with gastric residency, serves as a non-invasive alternative to implantation. Achieving gastric residency with hydrogels requires the hydrogels to swell very rapidly and to withstand gastric mechanical forces over time. However, high swelling ratio, high swelling speed, and long-term robustness do not coexist in existing hydrogels. Here, we introduce a hydrogel device that can be ingested as a standard-sized pill, swell rapidly into a large soft sphere, and maintain robustness under repeated mechanical loads in the stomach for up to one month. Large animal tests support the exceptional performance of the ingestible hydrogel device for long-term gastric retention and physiological monitoring.


Assuntos
Hidrogéis/química , Teste de Materiais , Monitorização Fisiológica/métodos , Administração Oral , Animais , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hidrogéis/efeitos adversos , Hidrogéis/toxicidade , Fenômenos Mecânicos , Estômago/efeitos dos fármacos
15.
Am J Physiol Heart Circ Physiol ; 316(3): H751-H761, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30681364

RESUMO

Extracorporeal circulation can be accompanied by increased vascular permeability leading to pathological fluid balance and organ dysfunction. The second messenger cAMP is involved in capillary permeability and maintains endothelial integrity. The aim of the present study was to evaluate the effect of phosphodiesterase-4 (PDE4) inhibition with rolipram on extracorporeal circulation-induced capillary leakage, microcirculatory dysfunction, and organ injury in rodents. Rats were randomly allocated to the following groups: sham ( n = 5), venoarterial extracorporeal circulation [extracorporeal life support (ECLS), n = 7], ECLS + rolipram ( n = 7), extracorporeal resuscitation (ECPR; n = 7), and ECPR + rolipram ( n = 7). In the groups that underwent ECPR, ECLS-based cardiopulmonary resuscitation (ECPR) was performed after the induction of hypoxic cardiac arrest. Upon return of spontaneous circulation, rolipram was administered intravenously. The mesenteric microcirculation was studied using intravital microscopy, and organ specimens were harvested upon completion of the study. ECLS and ECPR induced a proinflammatory response (cytokines IL-1ß, IL-6, and TNF-α). Although PDE4 expression was upregulated in vascular tissue, PDE4 inhibition abrogated impaired microcirculation and capillary leak (albumin extravasation of the sham group: 1 ± 0.03-fold, ECLS group: 1.2 ± 0.05-fold, ECLS + rolipram group: 0.99 ± 0.04-fold, ECPR group: 1.6 ± 0.04-fold, and ECPR + rolipram group: 1.06 ± 0.02-fold from the sham group, P < 0.05). PDE4 inhibition led to stabilization of vascular cAMP levels but did not affect cytokine levels. Capillary leak was reduced, as demonstrated by the decrease of the systemic biomarkers soluble vascular-endothelial cadherin and activated complement 3. Histological analysis revealed reduced injury to the lungs and kidneys after PDE4 inhibition, with a significant decrease in systemic renal damage markers. Our findings demonstrate that extracorporeal circulation causes an inflammatory reaction associated with decreased vascular cAMP levels, increased vascular permeability, and impaired microcirculation. PDE4 inhibition proved to be capable of reducing these side effects in ECLS and ECPR, leading to reduced microcirculatory, renal, and pulmonary injury. NEW & NOTEWORTHY Various complications are common after extracorporeal circulation. Among these, endothelial injury may cause impaired microcirculation and capillary leak. Here, we report that phosphodiesterase-4 inhibition targeting endothelial cAMP is capable of reducing microvascular complications in a rodent model of extracorporeal resuscitation. Microcirculation and vascular permeability are influenced without targeting extracorporeal circulation-induced inflammation. Thus, pulmonary and renal organ protection may be conferred.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Microcirculação/efeitos dos fármacos , Inibidores da Fosfodiesterase 4/farmacologia , Animais , Síndrome de Vazamento Capilar/etiologia , Síndrome de Vazamento Capilar/prevenção & controle , Débito Cardíaco/efeitos dos fármacos , Reanimação Cardiopulmonar , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/biossíntese , Citocinas/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Ressuscitação , Rolipram/farmacologia , Sistemas do Segundo Mensageiro
16.
Curr Pharm Des ; 24(20): 2264-2282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30039755

RESUMO

Heme oxygenase (HO), the rate-limiting step in the degradation of heme to biliverdin, ferrous ion, and carbon monoxide (CO), is an ancestral protective enzyme conserved across phylogenetic domains. While HO was first described in the late 1960s and progressively characterized in the following decades, there has been a surge of innovation over the past twenty years in efforts to leverage the cytoprotective power of HO in a clinical setting. Despite the plethora of preclinical data indicating extraordinary therapeutic potential, HO has remained elusive from the physician's toolbox. The leading candidate in development, CO, has long been misconstrued as a useless toxic gas. Scientists have crafted an array of CO delivery molecules and devices to harness HO, however, each endeavor was met with limitations preventing translation into clinical practice. In this discussion, we summarize the HO / CO field with a clinical and commercial development perspective. More specifically, given the enormous global efforts and capital investment into the field, we ask: where is the breakthrough therapy?


Assuntos
Monóxido de Carbono/metabolismo , Monóxido de Carbono/farmacologia , Heme Oxigenase-1/metabolismo , Animais , Indução Enzimática , Humanos
17.
Eur J Pharm Biopharm ; 130: 306-313, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30006245

RESUMO

Endogenously produced carbon monoxide (CO) has antioxidant and anti-inflammatory effects which is why CO has been investigated as a possible therapeutic agent for inflammatory disorders in different body systems, including the gastrointestinal (GI) tract. In an effort to develop an easy to use platform for CO delivery to the GI tract, we recently introduced the Oral CO Release System (OCORS) and demonstrated its preventive effect for experimental colitis in a rodent model. Building off on a comprehensive preclinical dataset on efficacy of inhaled and intraperitoneal CO in reducing postoperative ileus (POI), which is being defined as GI transit retardation after abdominal surgery, we evaluated an adapted OCORS platform to ameliorate POI by local CO delivery to the murine small intestine. To match design characteristics of OCORS with the murine physiology we developed a miniaturized version of the OCORS and tailored its release pattern to release CO for 2 h following first order kinetics. Upon intragastric gavage of 20 tablets, 55% of the tablets reached the murine small intestine after 1 h while triggering a blood carboxyhemoglobin rise to 5.2%. Although this is in line with previous systemic CO dosing protocols, GI muscular inflammation and transit retardation by small intestinal manipulation, performed at 1 h after gavage of 20 tablets, was not prevented while the positive control - intravenous nitrite - prevented POI. The results show that local CO treatment of POI is insufficient - suggesting a strong systemic component for effective therapy - thereby providing critical insight into effective design of CO drug delivery in POI.


Assuntos
Monóxido de Carbono/administração & dosagem , Sistemas de Liberação de Medicamentos , Íleus/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Administração Oral , Animais , Monóxido de Carbono/farmacologia , Carboxihemoglobina/metabolismo , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Íleus/etiologia , Intestino Delgado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Complicações Pós-Operatórias/patologia , Comprimidos
18.
J Control Release ; 279: 336-344, 2018 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-29655987

RESUMO

Carbon monoxide (CO) has demonstrated therapeutic potential in multiple inflammatory conditions including intensive care applications such as organ transplantation or sepsis. Approaches to translate these findings into future therapies, however, have been challenged by multiple hurdles including handling and toxicity issues associated with systemic CO delivery. Here, we describe a membrane-controlled Extracorporeal Carbon Monoxide Release System (ECCORS) for easy implementation into Extracorporeal Membrane Oxygenation (ECMO) setups, which are being used to treat cardiac and respiratory diseases in various intensive care applications. Functionalities of the ECCORS were investigated in a pig model of veno-arterial ECMO. By precisely controlling CO generation and delivery as a function of systemic carboxyhemoglobin levels, the system allows for an immediate onset of therapeutic CO-levels while preventing CO-toxicity. Systemic carboxyhemoglobin levels were profiled in real-time by monitoring exhaled CO levels as well as by pulse oximetry, enabling self-contained and automatic feedback control of CO generation within ECCORS. Machine learning based mathematical modeling was performed to increase the predictive power of this approach, laying foundation for high precision systemic CO delivery concepts of tomorrow.


Assuntos
Monóxido de Carbono/administração & dosagem , Carboxihemoglobina/metabolismo , Oxigenação por Membrana Extracorpórea/métodos , Modelos Teóricos , Animais , Monóxido de Carbono/toxicidade , Aprendizado de Máquina , Oximetria/métodos , Suínos
19.
Eur J Pharm Biopharm ; 118: 3-12, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27836646

RESUMO

The heme oxygenase (HO)/carbon monoxide (CO) system is a physiological feedback loop orchestrating various cell-protective effects in response to cellular stress. The therapeutic use of CO is impeded by safety challenges as a result of high CO-Hemoglobin formation following non-targeted, systemic administration jeopardizing successful CO therapies as of this biological barrier. Another caveat is the use of CO-Releasing Molecules containing toxicologically critical transition metals. An emerging number of local delivery approaches addressing these issues have recently been introduced and provide exciting new starting points for translating the fascinating preclinical potential of CO into a clinical setting. This review will discuss these approaches and link to future delivery strategies aiming at establishing CO as a safe and effective medication of tomorrow.


Assuntos
Monóxido de Carbono/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Heme Oxigenase-1/metabolismo , Heme/metabolismo , Compostos Organometálicos/farmacologia , Administração Cutânea , Administração por Inalação , Administração Oral , Animais , Biliverdina/metabolismo , Monóxido de Carbono/metabolismo , Monóxido de Carbono/uso terapêutico , Carboxihemoglobina/metabolismo , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Transplante de Órgãos/efeitos adversos , Compostos Organometálicos/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/etiologia , Transdução de Sinais , Distribuição Tecidual
20.
J Control Release ; 239: 128-36, 2016 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-27578097

RESUMO

Carbon monoxide (CO) is an endogenous signal transmitter involved in numerous physiological processes including the gastrointestinal (GI) homeostasis. CO has been recognized as potential new therapeutic agent for motility related and inflammatory disorders of the GI tract. A therapeutic use, however, is challenged by inappropriate drug delivery modes. Here we describe a micro scale Oral Carbon Monoxide Release System (M-OCORS) designed for localized and controlled exposure of the GI tract with in situ generated CO. M-OCORS allowed for controlled release profiles lasting for several minutes or up to almost one day. These in vitro release profiles translated into a large pharmacokinetic design space following oral administration in mice and measured as CO-hemoglobin (CO-Hb) formation. M-OCORS with a release profile featuring exposure of the intestine was profiled in two independently performed studies demonstrating preventive effects in chemically induced colitis. M-OCORS significantly reduced damage scores and prevented upregulation of colitis biomarkers.


Assuntos
Monóxido de Carbono/administração & dosagem , Colite/prevenção & controle , Sistemas de Liberação de Medicamentos/métodos , Compostos Organometálicos/administração & dosagem , Administração Oral , Animais , Monóxido de Carbono/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Colite/metabolismo , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Compostos Organometálicos/metabolismo
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