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2.
Sci Rep ; 11(1): 6355, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737657

RESUMO

Using two-sensor electrochemical recordings in freely moving rats, we examined the relationship between physiological and drug-induced oxygen fluctuations in the brain and periphery. Animals chronically implanted with oxygen sensors in the nucleus accumbens (NAc) and subcutaneous (SC) space were subjected to several mildly arousing stimuli (sound, tail-pinch and social interaction) and intravenous injections of cocaine and heroin. Arousing stimuli induced rapid increases in NAc oxygen levels followed by and correlated with oxygen decreases in the SC space. Therefore, cerebral vasodilation that increases cerebral blood flow and oxygen entry into brain tissue results from both direct neuronal activation and peripheral vasoconstriction, which redistributes arterial blood from periphery to the brain. The latter factor could also explain a similar pattern of oxygen responses found in the substantia nigra reticulata, suggesting hyperoxia as a global phenomenon with minor structural differences during early time intervals following the stimulus onset. While arousing stimuli and cocaine induced similar oxygen responses in the brain and SC space, heroin induced a biphasic down-up brain oxygen fluctuation associated with a monophasic oxygen decrease in the SC space. Oxygen decreases occurred more rapidly and stronger in the SC space, reflecting a drop in blood oxygen levels due to respiratory depression.


Assuntos
Encéfalo/fisiopatologia , Cocaína/efeitos adversos , Heroína/efeitos adversos , Neurônios/efeitos dos fármacos , Oxigênio/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Cocaína/farmacologia , Heroína/farmacologia , Humanos , Entorpecentes/efeitos adversos , Entorpecentes/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Fenômenos Fisiológicos/efeitos dos fármacos , Ratos , Ratos Long-Evans , Vigília/efeitos dos fármacos , Vigília/fisiologia
3.
Biomolecules ; 9(9)2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492031

RESUMO

The short postharvest life of cassava is mainly due to its rapid postharvest physiological deterioration (PPD) and cell oxidative damage, however, how to effectively control this remains elusive. In this study, South China 5 cassava slices were sprayed with water and methyl jasmonate (MeJA) to study the effects of MeJA on reactive oxygen species, antioxidant enzymes, quality, endogenous hormone levels, and melatonin biosynthesis genes. We found that exogenous MeJA could delay the deterioration rate for at least 36 h and alleviate cell oxidative damage through activation of superoxide dismutase, catalase, and peroxidase. Moreover, MeJA increased the concentrations of melatonin and gibberellin during PPD, which had a significant effect on regulating PPD. Notably, exogenous MeJA had a significant effect on maintaining cassava quality, as evidenced by increased ascorbic acid content and carotenoid content. Taken together, MeJA treatment is an effective and promising way to maintain a long postharvest life, alleviate cell oxidative damage, and regulate storage quality in cassava.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Manihot/efeitos dos fármacos , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Acetatos/química , Acetatos/isolamento & purificação , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Manihot/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxilipinas/química , Oxilipinas/isolamento & purificação , Fenômenos Fisiológicos/efeitos dos fármacos , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação
4.
J Proteomics ; 206: 103436, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31265922

RESUMO

We report the effects of protein from different duck products on the intestinal flora and physiology of rats. After 30 days of feeding, rats fed water-boiled salted duck protein had the lowest gut microbial diversity and richness. Allobaculum, Lactobacillus, Coprococcus and Eubacterium increased in rats fed wine-cured duck protein, while rats fed water-boiled salted and wine-cured duck protein showed increased serum urea (UREA) concentrations and serum cholesterol (CHOL) to HDL-cholesterol (HDLC) ratios, but decreased retroperitoneal white adipose tissue (rWAT) and perirenal white adipose tissue (pWAT) to body weight ratios. The changes in gut bacteria were mainly associated with the fat-mass index (weight of rWAT or pWAT to body weight ratio), accompanied by the opposite correlation with UREA content. SIGNIFICANCE: It showed that protein from different duck products impacted the intestinal flora and caused physiological changes in rats. Different sources of processed protein vary in their digestibility and digestive kinetics, all of which can affect the intestinal microbiota and physiology. We report the effects is an effort to map the complex interactions of "host physiology-nutrition-microbiota" in order to provide some insights into that food processing can be improved to promote beneficial gut microbes and enhance human health.


Assuntos
Patos , Manipulação de Alimentos , Microbioma Gastrointestinal/efeitos dos fármacos , Proteínas de Carne/farmacologia , Fenômenos Fisiológicos/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Dieta , Patos/metabolismo , Manipulação de Alimentos/métodos , Masculino , Produtos da Carne/análise , Ratos , Ratos Sprague-Dawley
5.
Aquat Toxicol ; 212: 20-27, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31039523

RESUMO

Polybrominated diphenyl ethers (PBDEs), a series of highly persistent organic pollutants (POPs), are ubiquitous in marine ecosystems. As key primary producers, microalgae are of great importance on evaluating the environmental outcome of PBDEs pollution. In this study, the toxic mechanisms of BDE-47 on the marine diatom Thalassiosira pseudonana were evaluated by measuring multiple physiological processes. Three concentrations of BDE-47 (25, 15 and 5 µg L-1) were used along with two controls (blank: no BDE-47 or DMSO; negative control: only DMSO). Experiments lasted 144 h (6 days), in which the actual BDE-47 concentrations, cell densities, nutrient (nitrate and phosphate) uptake, pigment compositions, photosynthetic physiology, cell morphology and cellular contents (organic carbon and nitrogen) were measured at 12-48 h intervals. The toxic mechanisms of BDE-47 on T. pseudonana cells were evaluated by measuring multiple physiological processes including photosynthesis, nutrient uptake, cellular material synthesis and cell cycle progressions. The cell divisions of T. pseudonana were severely inhibited by the stress of BDE-47, but the photosynthetic parameters were much less declined and recovered earlier than the cell divisions in the same BDE-47 treatments. The unsuppressed uptake rates of nutrients, increased cell volume and cellular contents indicated the cellular material synthesis proceeded normally. Finally, we found that the cell cycle was arrested in G2/M phase under the stress of BDE-47, we thus concluded that the inhibition of cell divisions by BDE-47 was not due to the lack of energy or cellular materials, where the cell cycle arrest happened; this might be the most important toxicological outcome.


Assuntos
Diatomáceas/efeitos dos fármacos , Diatomáceas/fisiologia , Éteres Difenil Halogenados/toxicidade , Fenômenos Fisiológicos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Carbono/metabolismo , Ciclo Celular/efeitos dos fármacos , Diatomáceas/citologia , Diatomáceas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Estresse Fisiológico/efeitos dos fármacos
6.
Int J Nanomedicine ; 14: 1563-1573, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880965

RESUMO

PURPOSE: Undesirable complement (C) activation by nanomedicines can entail an adverse immune reaction known as C activation-related pseudoallergy (CARPA) in sensitive patients. The syndrome includes cardiopulmonary, hemodynamic, and a variety of other physiological changes that have been well described in man, pigs, dogs, and rats. However, the information on CARPA is scarce and ambiguous in mice, a species widely used in preclinical studies. The present study aimed to fill this gap by exploring signs of CARPA in mice following i.v. administration of AmBisome and Abelcet, which are nano-formulations of Amphotericin B with high risk to cause CARPA. MATERIALS AND METHODS: Anesthetized NMRI mice were intravenously injected with liposomal amphotericin B (Abelcet and AmBisome; 30-300 mg phospholipid/kg), drug-free high cholesterol multilamellar vesicles (HC-MLV), and positive controls, cobra venom factor (CVF) and zymosan, followed by the measurement of blood pressure (BP), heart rate, white blood cell, and platelet counts and plasma thromboxane B2 (TXB2) levels. C activation was assessed by C3a ELISA, a C3 consumption assay (PAN-C3) and a modified sheep red blood cell hemolytic assay. RESULTS: All test agents, except HC-MLV, caused transient hypertension, thrombocytopenia, and elevation of plasma TXB2, which were paralleled by significant rises of plasma C3a in CVF and zymosan-treated animals, wherein the initial hypertension turned into hypotension and shock. Abelcet and AmBisome caused minor, delayed rise of C3a that was not associated with hypertension. The C3a receptor inhibitor SB-290157 attenuated the hypertension caused by Abelcet and decreased the BP thereafter. CONCLUSION: The parallelism between C3a anaphylatoxin production and severity of physiological changes caused by the different agents is consistent with CARPA underlying these changes. Although the reactive dose of liposomal phospholipids was substantially higher than that in other species (pigs, dogs), the mouse seems suitable for studying the mechanism of hypersensitivity reactions to liposomal formulations of amphotericin B, a frequent side effect of these drugs.


Assuntos
Anfotericina B/farmacologia , Ativação do Complemento/efeitos dos fármacos , Fenômenos Fisiológicos/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Hipertensão/fisiopatologia , Imunidade Inata/efeitos dos fármacos , Lipossomos , Masculino , Camundongos Endogâmicos C57BL , Receptores de Complemento/antagonistas & inibidores , Receptores de Complemento/metabolismo
7.
Biomed Eng Online ; 17(1): 72, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29866122

RESUMO

BACKGROUND: Air ions are molecules of air that have become ionized-that is, they have either lost or gained an electrical charge. Past speculation has suggested that exposure to positive air ions may be harmful to one's health, while exposure to negative air ions may be associated with beneficial health effects. Air ions arise from natural sources as well as direct-current transmission lines and commercial ionizers. Several recent clinical studies have suggested therapeutic effects of air ions on various types of depression at exposure levels 10- to 1000-fold higher than most previous human studies. The aim of this study was to assess the evidence from studies of laboratory animals for beneficial or adverse effects of air ions on health. METHODS: Sixty-two studies (1935-2015) in nine topics areas were evaluated for quality and potential systematic bias by ARRIVE guidelines. Standardized mean differences or proportional differences between exposed and control groups were computed for 44 studies to quantitatively assess the strength of the evidence for exposure-related effects. RESULTS: Many of the studies were conducted before 1990 and exhibited various reporting and methodological deficiencies, including small sample size, failure to control for the influence of potential confounding variables, lack of randomized assignment to treatment groups and blinded analyses, and statistical errors relating to treating group-exposed animals as individuals. The highest quality studies consistently reported no effects of exposure on any of the endpoints examined. There were no evident dose-response relationships within or across studies. CONCLUSIONS: Experimental studies of laboratory animals exposed to positive and negative air ions for minutes to years over a five-log unit range of intensities did not suggest any consistent or reliable effects on measures of behavior, learning and memory, neurotransmitters, tracheal function, respiratory infection, cardiovascular function, reproduction and growth, carcinogenesis, or other health endpoints. These data do not provide evidence of adverse or beneficial effects of air ion exposure on health, and did not suggest any biological mechanism of interaction, except perhaps for mechanosensory stimulation of body surfaces by static electric fields at high air ion concentrations.


Assuntos
Ar , Animais de Laboratório , Comportamento Animal/efeitos dos fármacos , Fenômenos Fisiológicos/efeitos dos fármacos , Animais
8.
Parasitol Int ; 67(4): 403-412, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29617630

RESUMO

Control of morbidity associated with schistosomiasis via chemotherapy largely relies on the drug praziquantel. Repeated therapy with praziquantel has created concerns about the possible selection of resistant worms and necessitated the search for novel drugs to treat schistosomiasis. Here, a murine model was infected with Schistosoma mansoni and treated with oral 1,2,6,7-tetraoxaspiro [7.11] nonadecane (N-89), which caused a significant reduction in fecundity and egg burden and reduced morbidity when administered at 5-weeks post-infection. The analysis showed that the mode of action occurred through the ingestion of activated N-89 by the worms, and that there was no direct external effect on the S. mansoni worms. Ultrastructural analysis of the treated worms showed disruptions in the gut lumen and the presence of large volumes of material, suggestive of undigested blood meals or red blood cells. In addition, there were reduced vitelline cells in female worms and damage to sub-tegmental musculature in male worms. Eggs recovered from the treated mice showed both damage to the eggs and the production of immature eggs. Expression of mRNA responsible for gut and digestive function and egg production was also significantly affected by N-89 treatment, whereas control genes for musculature showed no significant changes. Thus, N-89 drastically affected the total digestive function and egg production of S. mansoni worms. Physiological processes requiring heme uptake such as egg production and eggshell formation were subsequently affected, suggesting that the compound could be a possible therapeutic drug candidate for schistosomiasis control.


Assuntos
Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Fenômenos Fisiológicos/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Compostos de Espiro/uso terapêutico , Animais , Modelos Animais de Doenças , Compostos Heterocíclicos com 2 Anéis/administração & dosagem , Compostos Heterocíclicos com 2 Anéis/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/parasitologia , Camundongos , Oócitos/efeitos dos fármacos , Contagem de Ovos de Parasitas , Esquistossomose/tratamento farmacológico , Esquistossomose/parasitologia , Esquistossomose mansoni/parasitologia , Compostos de Espiro/administração & dosagem , Compostos de Espiro/efeitos adversos
9.
Cell ; 173(1): 166-180.e14, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29502969

RESUMO

Brain-wide fluctuations in local field potential oscillations reflect emergent network-level signals that mediate behavior. Cracking the code whereby these oscillations coordinate in time and space (spatiotemporal dynamics) to represent complex behaviors would provide fundamental insights into how the brain signals emotional pathology. Using machine learning, we discover a spatiotemporal dynamic network that predicts the emergence of major depressive disorder (MDD)-related behavioral dysfunction in mice subjected to chronic social defeat stress. Activity patterns in this network originate in prefrontal cortex and ventral striatum, relay through amygdala and ventral tegmental area, and converge in ventral hippocampus. This network is increased by acute threat, and it is also enhanced in three independent models of MDD vulnerability. Finally, we demonstrate that this vulnerability network is biologically distinct from the networks that encode dysfunction after stress. Thus, these findings reveal a convergent mechanism through which MDD vulnerability is mediated in the brain.


Assuntos
Encéfalo/fisiologia , Depressão/patologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Depressão/fisiopatologia , Modelos Animais de Doenças , Estimulação Elétrica , Eletrodos Implantados , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Ketamina/farmacologia , Aprendizado de Máquina , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fenômenos Fisiológicos/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Estresse Psicológico
10.
Mol Cell Endocrinol ; 464: 14-20, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28159654

RESUMO

Anabolic androgenic steroids (AAS) are widely abused by the sporting community. Demonstrating performance enhancing effects of AAS in rigorous scientific studies is fraught with difficulty. In controlled studies, AAS have consistently been reported to increase muscle mass and strength. The clinical evidence that these anabolic effects are independent of, and additive to exercise are supported by preclinical studies suggesting that AAS and exercise affect muscle by overlapping, yet distinct mechanisms. AAS may also improve performance by their actions on other organ systems, such as the vasculature, and the erythropoietic and central nervous system, although this evidence is less strong. While most of the actions of AAS are thought to be mediated via classical androgen receptor-mediated genomic signalling, AAS may also produce rapid effects via non-genomic mechanisms.


Assuntos
Anabolizantes/farmacologia , Androgênios/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Fenômenos Fisiológicos/efeitos dos fármacos , Humanos , Músculos/efeitos dos fármacos , Músculos/fisiologia
11.
Drug Metab Pharmacokinet ; 33(1): 40-42, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29217459

RESUMO

Microphysiological systems (MPS) are currently attracting a lot of interest from pharmaceutical companies worldwide. In the United States and European Union, several large government projects related to MPS have been initiated, and, in Japan, pharmaceutical companies interested in MPS are watching the recent trends and developments in the field. In July 2017, the Japan Agency for Medical Research and Development initiated a research program to develop chip-based MPS. In this review, we examine the technical aspects of commercializing chip-based MPS.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Indústria Farmacêutica/tendências , Preparações Farmacêuticas/metabolismo , Fenômenos Fisiológicos/fisiologia , Análise Serial de Proteínas/tendências , Indústria Farmacêutica/métodos , Humanos , Preparações Farmacêuticas/administração & dosagem , Fenômenos Fisiológicos/efeitos dos fármacos , Análise Serial de Proteínas/métodos
12.
Int J Biol Macromol ; 108: 1300-1309, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29138000

RESUMO

A prospective completely randomized experimental study was conducted using 48 animals to evaluate the physiometabolic effects of Agave salmiana fructans as a dietary supplement in healthy Wistar rats. Five fructans concentrations from 5 to 20% (w/w) and one control were used in the rats' diet and were divided into six groups (n=8 rats/group). The treatments were carried out for 35days, during which glucose, cholesterol, triglycerides, body-weight gain, food intake, fecal excretion, organ weights, renal and hepatic functions and a histological analysis of the cecum were evaluated. Glucose, cholesterol, triglycerides, renal and hepatic functions were not significantly affected by any treatment. Body-weight gain and food intake were lower in the rat groups fed fructans than in the control group. Increased fecal excretion (p<0.05) was observed only in animals fed 12.5 and 20% fructans. Mice supplemented with fructans exhibited increased weight and length (p<0.05) in the cecum and colon. A histological analysis of the cecum showed cellular proliferation with a dose of 12.5% and membrane lysis at doses of 15 and 20%. In conclusion, the inclusion of 12.5% of Agave salmiana fructans in the animals' diets exerts beneficial physiometabolic effects after the seventh treatment day.


Assuntos
Agave/química , Frutanos/farmacologia , Metabolismo/efeitos dos fármacos , Fenômenos Fisiológicos/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Ceco/anatomia & histologia , Ceco/química , Ceco/efeitos dos fármacos , Colesterol/sangue , Colo/anatomia & histologia , Colo/química , Colo/efeitos dos fármacos , Suplementos Nutricionais/análise , Ingestão de Líquidos/efeitos dos fármacos , Fezes/química , Concentração de Íons de Hidrogênio , Rim/efeitos dos fármacos , Rim/fisiologia , Fígado/efeitos dos fármacos , Fígado/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar , Triglicerídeos/sangue
13.
PLoS One ; 12(3): e0174423, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28328950

RESUMO

Repeated anaesthesia may be required in experimental protocols and in daily veterinary practice, but anaesthesia is known to alter physiological parameters in GPs (Cavia porcellus, GPs). This study investigated the effects of repeated anaesthesia with either medetomidine-midazolam-fentanyl (MMF) or isoflurane (Iso) on physiological parameters in the GP. Twelve GPs were repeatedly administered with MMF or Iso in two anaesthesia sets. One set consisted of six 40-min anaesthesias, performed over 3 weeks (2 per week); the anaesthetic used first was randomized. Prior to Iso anaesthesia, atropine was injected. MMF anaesthesia was antagonized with AFN (atipamezole-flumazenil-naloxone). Abdominally implanted radio-telemetry devices recorded the mean arterial blood pressure (MAP), heart rate (HR) and core body temperature continuously. Additionally, respiratory rate, blood glucose and body weight were assessed. An operable state could be achieved and maintained for 40 min in all GPs. During the surgical tolerance with MMF, the GPs showed a large MAP range between the individuals. In the MMF wake- up phase, the time was shortened until the righting reflex (RR) returned and that occurred at lower MAP and HR values. Repeated Iso anaesthesia led to an increasing HR during induction (anaesthesias 2-6), non-surgical tolerance (anaesthesias 3-6) and surgical tolerance (anaesthesias 4, 6). Both anaesthetics may be used repeatedly, as repeating the anaesthesias resulted in only slightly different physiological parameters, compared to those seen with single anaesthesias. The regular atropine premedication induced HR increases and repeated MMF anaesthesia resulted in a metabolism increase which led to the faster return of RR. Nevertheless, Iso's anaesthesia effects of strong respiratory depression and severe hypotension remained. Based on this increased anaesthesia risk with Iso, MMF anaesthesia is preferable for repeated use in GPs.


Assuntos
Fentanila/administração & dosagem , Isoflurano/administração & dosagem , Medetomidina/administração & dosagem , Midazolam/administração & dosagem , Fenômenos Fisiológicos/efeitos dos fármacos , Anestesia/métodos , Anestésicos Combinados/administração & dosagem , Animais , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Masculino , Taxa Respiratória/efeitos dos fármacos
14.
BMC Syst Biol ; 11(Suppl 7): 129, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29322928

RESUMO

BACKGROUND: Drug development considering individual varieties among patients becomes crucial to improve clinical development success rates and save healthcare costs. As a useful tool to predict individual phenomena and correlations among drug characteristics and individual varieties, recently, whole-body physiologically based pharmacokinetic (WB- PBPK) models are getting more attention. WB-PBPK models generally have a lot of drug-related parameters that need to be estimated, and the estimations are difficult because the observed data are limited. Furthermore, parameter estimation in WB-PBPK models may cause overfitting when applying to individual clinical data such as urine/feces drug excretion for each patient in which Cluster Newton Method (CNM) is applicable for parameter estimation. In order to solve this issue, we came up with the idea of constraint-based perturbation analysis of the CNM. The effectiveness of our approach is demonstrated in the case of irinotecan WB-PBPK model using common organ-specific tissue-plasma partition coefficients (Kp) among the patients as constraints in WB-PBPK parameter estimation. RESULTS: We find strong correlations between age, renal clearance and liver functions in irinotecan WB-PBPK model with personalized physiological parameters by observing the distributions of optimized values of strong convergence drug-related parameters using constraint-based perturbation analysis on CNM. The constraint-based perturbation analysis consists of the following three steps: (1) Estimation of all drug-related parameters for each patient; the parameters include organ-specific Kp. (2) Fixing suitable values of Kp for each organ among all patients identically. (3) Re-estimation of all drug-related parameters other than Kp by using the fixed values of Kp as constraints of CNM. CONCLUSIONS: Constraint-based perturbation analysis could yield new findings when using CNM with appropriate constraints. This method is a new technique to find suitable values and important insights that are masked by CNM without constraints.


Assuntos
Descoberta de Drogas , Modelos Biológicos , Farmacocinética , Fenômenos Fisiológicos/efeitos dos fármacos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Clin Pharmacol Ther ; 102(1): 98-105, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27770430

RESUMO

Physiologically based pharmacokinetic (PBPK) modeling is a valuable tool in drug development and regulatory assessment, as it offers the opportunity to simulate the pharmacokinetics of a compound, with a mechanistic understanding, in a variety of populations and situations. This work reviews the use and impact of such modeling in selected regulatory procedures submitted to the European Medicines Agency (EMA) before the end of 2015, together with its subsequent reflection in public documents relating to the assessment of these procedures. It is apparent that the reference to PBPK modeling in regulatory public documents underrepresents its use. A positive trend over time of the number of PBPK models submitted is shown, and in a number of cases the results of these may impact the decision-making process or lead to recommendations in the product labeling. These results confirm the need for regulatory guidance in this field, which is currently under development by the EMA.


Assuntos
Desenvolvimento de Medicamentos , Controle de Medicamentos e Entorpecentes , Modelos Biológicos , Farmacocinética , Desenvolvimento de Medicamentos/métodos , Desenvolvimento de Medicamentos/normas , Controle de Medicamentos e Entorpecentes/métodos , Controle de Medicamentos e Entorpecentes/organização & administração , Europa (Continente) , Órgãos Governamentais , Humanos , Avaliação das Necessidades , Fenômenos Fisiológicos/efeitos dos fármacos , Formulação de Políticas
16.
J Pharm Sci ; 106(3): 734-737, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27915208

RESUMO

The challenge of bringing innovative medicines to patients in combination with intense competition within the pharmaceutical industry has induced companies to develop quality medicines more efficiently and cost-effectively. State-of-the-art approaches to advance drug development have never been so urgent. One such approach that has been gaining traction within the industry is the application of modeling and simulation. In this commentary, the benefits of physiologically based oral absorption modeling and simulation in drug development are highlighted and suggestions for maximizing its impact are provided.


Assuntos
Simulação por Computador , Absorção Gastrointestinal/fisiologia , Modelos Biológicos , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/metabolismo , Administração Oral , Absorção Gastrointestinal/efeitos dos fármacos , Humanos , Fenômenos Fisiológicos/efeitos dos fármacos , Fenômenos Fisiológicos/fisiologia
17.
PLoS One ; 11(11): e0166060, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829053

RESUMO

Insect odorant receptors (ORs) are 7-transmembrane receptors with inverse membrane topology. They associate with the conserved ion channel Orco. As chaperon, Orco maintains ORs in cilia and, as pacemaker channel, Orco controls spontaneous activity in olfactory receptor neurons. Odorant binding to ORs opens OR-Orco receptor ion channel complexes in heterologous expression systems. It is unknown, whether this also occurs in vivo. As an alternative to this ionotropic transduction, experimental evidence is accumulating for metabotropic odor transduction, implicating that insect ORs couple to G-proteins. Resulting second messengers gate various ion channels. They generate the sensillum potential that elicits phasic-tonic action potentials (APs) followed by late, long-lasting pheromone responses. Because it is still unclear how and when Orco opens after odor-OR-binding, we used tip recordings to examine in vivo the effects of the Orco antagonist OLC15 and the amilorides MIA and HMA on bombykal transduction in the hawkmoth Manduca sexta. In contrast to OLC15 both amilorides decreased the pheromone-dependent sensillum potential amplitude and the frequency of the phasic AP response. Instead, OLC15 decreased spontaneous activity, increased latencies of phasic-, and decreased frequencies of late, long-lasting pheromone responses Zeitgebertime-dependently. Our results suggest no involvement for Orco in the primary transduction events, in contrast to amiloride-sensitive channels. Instead of an odor-gated ionotropic receptor, Orco rather acts as a voltage- and apparently second messenger-gated pacemaker channel controlling the membrane potential and hence threshold and kinetics of the pheromone response.


Assuntos
Proteínas de Insetos/fisiologia , Manduca/fisiologia , Feromônios/fisiologia , Receptores Odorantes/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Western Blotting , Células Cultivadas , Proteínas de Insetos/metabolismo , Ativação do Canal Iônico/efeitos dos fármacos , Canais Iônicos/metabolismo , Canais Iônicos/fisiologia , Masculino , Manduca/metabolismo , Odorantes , Neurônios Receptores Olfatórios/efeitos dos fármacos , Neurônios Receptores Olfatórios/metabolismo , Neurônios Receptores Olfatórios/fisiologia , Feromônios/farmacologia , Fenômenos Fisiológicos/efeitos dos fármacos , Receptores Odorantes/agonistas , Receptores Odorantes/antagonistas & inibidores , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Sistemas do Segundo Mensageiro/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Tioglicolatos/farmacologia , Triazóis/farmacologia
18.
J Environ Sci Health B ; 51(11): 781-9, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27428931

RESUMO

To understand the mechanism underlying organophosphate pesticide toxicity, cyanobacterium Anabaena PCC 7120 was subjected to varied concentrations (0, 5, 10, 20 and 30 mg L(-1)) of profenofos and the effects were investigated in terms of changes in cellular physiology, genomic template stability and protein expression pattern. The supplementation of profenofos reduced the growth, total pigment content and photosynthetic efficiency of the test organism in a dose dependent manner with maximum toxic effect at 30 mg L(-1). The high fluorescence intensity of 2', 7' -dichlorofluorescin diacetate and increased production of malondialdehyde confirmed the prevalence of acute oxidative stress condition inside the cells of the cyanobacterium. Rapid amplified polymorphic DNA (RAPD) fingerprinting and SDS-PAGE analyses showed a significant alteration in the banding patterns of DNA and proteins respectively. A marked increase in superoxide dismutase, catalase, peroxidase activity and a concomitant reduction in glutathione content indicated their possible role in supporting the growth of Anabaena 7120 up to 20 mg L(-1). These findings suggest that the uncontrolled use of profenofos in the agricultural fields may not only lead to the destruction of the cyanobacterial population, but it would also disturb the nutrient dynamics and energy flow.


Assuntos
Anabaena/enzimologia , Catalase/metabolismo , DNA de Algas/efeitos dos fármacos , Inseticidas/toxicidade , Malondialdeído/toxicidade , Organotiofosfatos/toxicidade , Fenômenos Fisiológicos/efeitos dos fármacos , Anabaena/efeitos dos fármacos , Catalase/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Inseticidas/metabolismo , Malondialdeído/metabolismo , Organotiofosfatos/metabolismo , Fotossíntese/efeitos dos fármacos , Técnica de Amplificação ao Acaso de DNA Polimórfico , Superóxido Dismutase/efeitos dos fármacos
19.
AAPS J ; 18(5): 1067-1081, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27365096

RESUMO

The programme for the 2015 AAPS Annual Meeting and Exhibition (Orlando, FL; 25-29 October 2015) included a sunrise session presenting an overview of the state-of-the-art tools for in vitro-in vivo extrapolation (IVIVE) and mechanistic prediction of renal drug disposition. These concepts are based on approaches developed for prediction of hepatic clearance, with consideration of scaling factors physiologically relevant to kidney and the unique and complex structural organisation of this organ. Physiologically relevant kidney models require a number of parameters for mechanistic description of processes, supported by quantitative information on renal physiology (system parameters) and in vitro/in silico drug-related data. This review expands upon the themes raised during the session and highlights the importance of high quality in vitro drug data generated in appropriate experimental setup and robust system-related information for successful IVIVE of renal drug disposition. The different in vitro systems available for studying renal drug metabolism and transport are summarised and recent developments involving state-of-the-art technologies highlighted. Current gaps and uncertainties associated with system parameters related to human kidney for the development of physiologically based pharmacokinetic (PBPK) model and quantitative prediction of renal drug disposition, excretion, and/or metabolism are identified.


Assuntos
Rim/metabolismo , Taxa de Depuração Metabólica/fisiologia , Modelos Biológicos , Preparações Farmacêuticas/metabolismo , Fenômenos Fisiológicos/fisiologia , Animais , Congressos como Assunto , Humanos , Técnicas In Vitro , Rim/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Taxa de Depuração Metabólica/efeitos dos fármacos , Preparações Farmacêuticas/administração & dosagem , Fenômenos Fisiológicos/efeitos dos fármacos
20.
Dev Period Med ; 20(1): 61-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27416627

RESUMO

In this article we present the results of recent studies on the mechanism of action and biological role of α-ketoglutaric acid (AKG) in animals including developmental period of life. AKG is an intermediate in the Krebs cycle, which generates energy for life processes. Administration of AKG has been shown to be beneficial for proper development and function of the skeletal system during growth of young organisms, as well as in adulthood. In the form of a dietary supplement it also contributes to inhibition of osteoporosis in women. Moreover, it promotes the growth of muscle mass and accelerates wound healing. AKG has a significant impact on the morphology of the gastrointestinal tract in healthy animals and animals with damaged gastrointestinal tract mucosa. It is also a promising substance for the treatment of patients with short bowel syndrome, as it stimulates beneficial changes in intestinal morphology. Recent research has also revealed that AKG has neuroprotective effects.


Assuntos
Osso e Ossos/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Crescimento/efeitos dos fármacos , Ácidos Cetoglutáricos/metabolismo , Ácidos Cetoglutáricos/farmacologia , Músculos/efeitos dos fármacos , Fenômenos Fisiológicos/efeitos dos fármacos , Animais , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia
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