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1.
Bioinformatics ; 40(5)2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38741151

RESUMO

MOTIVATION: Systems biology aims to better understand living systems through mathematical modelling of experimental and clinical data. A pervasive challenge in quantitative dynamical modelling is the integration of time series measurements, which often have high variability and low sampling resolution. Approaches are required to utilize such information while consistently handling uncertainties. RESULTS: We present BayModTS (Bayesian modelling of time series data), a new FAIR (findable, accessible, interoperable, and reusable) workflow for processing and analysing sparse and highly variable time series data. BayModTS consistently transfers uncertainties from data to model predictions, including process knowledge via parameterized models. Further, credible differences in the dynamics of different conditions can be identified by filtering noise. To demonstrate the power and versatility of BayModTS, we applied it to three hepatic datasets gathered from three different species and with different measurement techniques: (i) blood perfusion measurements by magnetic resonance imaging in rat livers after portal vein ligation, (ii) pharmacokinetic time series of different drugs in normal and steatotic mice, and (iii) CT-based volumetric assessment of human liver remnants after clinical liver resection. AVAILABILITY AND IMPLEMENTATION: The BayModTS codebase is available on GitHub at https://github.com/Systems-Theory-in-Systems-Biology/BayModTS. The repository contains a Python script for the executable BayModTS workflow and a widely applicable SBML (systems biology markup language) model for retarded transient functions. In addition, all examples from the paper are included in the repository. Data and code of the application examples are stored on DaRUS: https://doi.org/10.18419/darus-3876. The raw MRI ROI voxel data were uploaded to DaRUS: https://doi.org/10.18419/darus-3878. The steatosis metabolite data are published on FairdomHub: 10.15490/fairdomhub.1.study.1070.1.


Assuntos
Teorema de Bayes , Fluxo de Trabalho , Animais , Ratos , Humanos , Camundongos , Biologia de Sistemas/métodos , Fígado/metabolismo , Software , Imageamento por Ressonância Magnética/métodos
2.
Biomech Model Mechanobiol ; 23(2): 631-653, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402347

RESUMO

Metabolic zonation refers to the spatial separation of metabolic functions along the sinusoidal axes of the liver. This phenomenon forms the foundation for adjusting hepatic metabolism to physiological requirements in health and disease (e.g., metabolic dysfunction-associated steatotic liver disease/MASLD). Zonated metabolic functions are influenced by zonal morphological abnormalities in the liver, such as periportal fibrosis and pericentral steatosis. We aim to analyze the interplay between microperfusion, oxygen gradient, fat metabolism and resulting zonated fat accumulation in a liver lobule. Therefore we developed a continuum biomechanical, tri-phasic, bi-scale, and multicomponent in silico model, which allows to numerically simulate coupled perfusion-function-growth interactions two-dimensionally in liver lobules. The developed homogenized model has the following specifications: (i) thermodynamically consistent, (ii) tri-phase model (tissue, fat, blood), (iii) penta-substances (glycogen, glucose, lactate, FFA, and oxygen), and (iv) bi-scale approach (lobule, cell). Our presented in silico model accounts for the mutual coupling between spatial and time-dependent liver perfusion, metabolic pathways and fat accumulation. The model thus allows the prediction of fat development in the liver lobule, depending on perfusion, oxygen and plasma concentration of free fatty acids (FFA), oxidative processes, the synthesis and the secretion of triglycerides (TGs). The use of a bi-scale approach allows in addition to focus on scale bridging processes. Thus, we will investigate how changes at the cellular scale affect perfusion at the lobular scale and vice versa. This allows to predict the zonation of fat distribution (periportal or pericentral) depending on initial conditions, as well as external and internal boundary value conditions.


Assuntos
Fígado Gorduroso , Fígado , Humanos , Fígado/fisiologia , Glucose , Ácido Láctico/metabolismo , Fígado Gorduroso/metabolismo , Simulação por Computador , Oxigênio/metabolismo
3.
Front Pharmacol ; 15: 1404938, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818378

RESUMO

There is a lack of systematic research exploring cross-species variation in liver lobular geometry and zonation patterns of critical drug-metabolizing enzymes, a knowledge gap essential for translational studies. This study investigated the critical interplay between lobular geometry and key cytochrome P450 (CYP) zonation in four species: mouse, rat, pig, and human. We developed an automated pipeline based on whole slide images (WSI) of hematoxylin-eosin-stained liver sections and immunohistochemistry. This pipeline allows accurate quantification of both lobular geometry and zonation patterns of essential CYP proteins. Our analysis of CYP zonal expression shows that all CYP enzymes (besides CYP2D6 with panlobular expression) were observed in the pericentral region in all species, but with distinct differences. Comparison of normalized gradient intensity shows a high similarity between mice and humans, followed by rats. Specifically, CYP1A2 was expressed throughout the pericentral region in mice and humans, whereas it was restricted to a narrow pericentral rim in rats and showed a panlobular pattern in pigs. Similarly, CYP3A4 is present in the pericentral region, but its extent varies considerably in rats and appears panlobular in pigs. CYP2D6 zonal expression consistently shows a panlobular pattern in all species, although the intensity varies. CYP2E1 zonal expression covered the entire pericentral region with extension into the midzone in all four species, suggesting its potential for further cross-species analysis. Analysis of lobular geometry revealed an increase in lobular size with increasing species size, whereas lobular compactness was similar. Based on our results, zonated CYP expression in mice is most similar to humans. Therefore, mice appear to be the most appropriate species for drug metabolism studies unless larger species are required for other purposes, e.g., surgical reasons. CYP selection should be based on species, with CYP2E1 and CYP2D6 being the most preferable to compare four species. CYP1A2 could be considered as an additional CYP for rodent versus human comparisons, and CYP3A4 for mouse/human comparisons. In conclusion, our image analysis pipeline together with suggestions for species and CYP selection can serve to improve future cross-species and translational drug metabolism studies.

4.
J Nat Prod ; 76(2): 178-85, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23363083

RESUMO

Assignment of the absolute configuration of cyclic peptides frequently yields challenges, leaving one or more stereogenic centers unassigned due to small quantities of sample and the limited utility of Marfey's or other methods for assigning amino or hydroxy acids. Here, we report isolation of kahalalide Y (1) from Bryopsis pennata for the first time; in addition, the application of a combination of molecular modeling and NOE distance constraint calculations was utilized to determine the conformation of 1 and the absolute configuration of the final stereogenic center of 1. Using the Schrödinger suite, the structure of 1 was sketched in Maestro and minimized using the OPLS2005 force field in Macromodel. A conformational search was performed separately for structures having an R or S configuration at C-3 of the beta-hydroxy fatty acid subunit that completes the cyclic scaffold of 1, after which multiple minimizations for all generated conformers were carried out. The lowest energy conformers of R and S stereoisomers were then subjected to B3LYP geometry optimizations including solvent effects. The S stereoisomer was shown to be in excellent agreement with the NOE-derived distance constraints and hydrogen-bonding stability studies.


Assuntos
Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Modelos Químicos , Moluscos/química , Animais , Havaí , Ligação de Hidrogênio , Conformação Molecular , Ressonância Magnética Nuclear Biomolecular/métodos , Estereoisomerismo
5.
J Vis Exp ; (199)2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37811934

RESUMO

This protocol presents an optimized erythrocytes-free NEVLP system using mouse livers. Ex vivo preservation of mouse livers was achieved by employing modified cannulas and techniques adapted from conventional commercial ex vivo perfusion equipment. The system was utilized to evaluate the preservation outcomes following 12 h of perfusion. C57BL/6J mice served as liver donors, and the livers were explanted by cannulating the portal vein (PV) and bile duct (BD), and subsequently flushing the organ with warm (37 °C) heparinized saline. Then, the explanted livers were transferred to the perfusion chamber and subjected to normothermic oxygenated machine perfusion (NEVLP). Inlet and outlet perfusate samples were collected at 3 h intervals for perfusate analysis. Upon completion of the perfusion, liver samples were obtained for histological analysis, with morphological integrity assessed using modified Suzuki-Score through Hematoxylin-Eosin (HE) staining. The optimization experiments yielded the following findings: (1) mice weighing over 30 g were deemed more suitable for the experiment due to the larger size of their bile duct (BD). (2) a 2 Fr (outer diameter = 0.66 mm) polyurethane cannula was better suited for cannulating the portal vein (PV) when compared to a polypropylene cannula. This was attributed to the polyurethane material's enhanced grip, resulting in reduced catheter slippage during the transfer from the body to the organ chamber. (3) for cannulation of the bile duct (BD), a 1 Fr (outer diameter = 0.33 mm) polyurethane cannula was found to be more effective compared to the polypropylene UT - 03 (outer diameter = 0.30 mm) cannula. With this optimized protocol, mouse livers were successfully preserved for a duration of 12 h without significant impact on the histological structure. Hematoxylin-Eosin (HE) staining revealed a well-preserved morphological architecture of the liver, characterized by predominantly viable hepatocytes with clearly visible nuclei and mild dilation of hepatic sinusoids.


Assuntos
Transplante de Fígado , Polipropilenos , Camundongos , Animais , Amarelo de Eosina-(YS) , Hematoxilina , Poliuretanos , Transplante de Fígado/métodos , Preservação de Órgãos/métodos , Camundongos Endogâmicos C57BL , Fígado/patologia , Perfusão/métodos
6.
Sci Rep ; 12(1): 21825, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36528753

RESUMO

Little is known about the impact of morphological disorders in distinct zones on metabolic zonation. It was described recently that periportal fibrosis did affect the expression of CYP proteins, a set of pericentrally located drug-metabolizing enzymes. Here, we investigated whether periportal steatosis might have a similar effect. Periportal steatosis was induced in C57BL6/J mice by feeding a high-fat diet with low methionine/choline content for either two or four weeks. Steatosis severity was quantified using image analysis. Triglycerides and CYP activity were quantified in photometric or fluorometric assay. The distribution of CYP3A4, CYP1A2, CYP2D6, and CYP2E1 was visualized by immunohistochemistry. Pharmacokinetic parameters of test drugs were determined after injecting a drug cocktail (caffeine, codeine, and midazolam). The dietary model resulted in moderate to severe mixed steatosis confined to periportal and midzonal areas. Periportal steatosis did not affect the zonal distribution of CYP expression but the activity of selected CYPs was associated with steatosis severity. Caffeine elimination was accelerated by microvesicular steatosis, whereas midazolam elimination was delayed in macrovesicular steatosis. In summary, periportal steatosis affected parameters of pericentrally located drug metabolism. This observation calls for further investigations of the highly complex interrelationship between steatosis and drug metabolism and underlying signaling mechanisms.


Assuntos
Fígado Gorduroso , Midazolam , Camundongos , Animais , Midazolam/farmacologia , Cafeína/farmacocinética , Taxa de Depuração Metabólica , Sistema Enzimático do Citocromo P-450/metabolismo
7.
Nat Prod Res ; 36(7): 1842-1850, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32945198

RESUMO

Four undescribed cembranoids, sarcoroseolides A-D (1-4) along with nine reported related cembranoids (5-13) were isolated from the soft coral Sarcophyton roseum. The chemical structures of sarcoroseolides A-D were elucidated by extensive 1 D and 2 D NMR as well as HR-ESIMS spectroscopic data. Moreover, the geometric and absolute configurations were assigned by the modified Mosher's method and/or NOESY experiments. The extract and the isolated metabolites were evaluated for their potential anti-inflammatory and cytotoxic activities.


Assuntos
Antozoários , Diterpenos , Animais , Antozoários/química , Diterpenos/química , Diterpenos/farmacologia , Oceano Índico , Espectroscopia de Ressonância Magnética , Estrutura Molecular
8.
Phytochemistry ; 183: 112598, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33360527

RESUMO

The metabolism of papaverine, the opium benzylisoquinoline alkaloid, with Aspergillus niger NRRL 322, Beauveria bassiana NRRL 22864, Cunninghamella echinulate ATCC 18968 and Cunninghamella echinulate ATCC 1382 has resulted in O-demethylation, O-methylglucosylation and N-oxidation products. Two new metabolites (4″-O-methyl-ß-D-glucopyranosyl) 4'-demethyl papaverine and (4″-O-methyl-ß-D-glucopyranosyl) 6-demethyl papaverine, (Metabolites 5 and 6) together with 4'-O-demethylated papaverine (Metabolite 1), 3'-O-demethylated papaverine (Metabolite 2), 6-O-demethylated papaverine (Metabolite 3) and papaverine N-oxide (Metabolite 4) were isolated. The structure elucidation of the metabolites was based primarily on 1D, 2D-NMR analyses and HRMS. These metabolism results were consistent with the previous plant cell transformation studies on papaverine and isopapaverine and the microbial metabolism of papaveraldine. In silico docking studies of the metabolites using crystals of human phosphodiesterase 10a (hPDE10a) revealed that compounds 4, 1, 6, 3, and 5 possess better docking scores and binding poses with favorable interactions than the native ligand papaverine.


Assuntos
Cunninghamella , Papaverina , Biotransformação , Simulação por Computador , Humanos , Diester Fosfórico Hidrolases
9.
Phytochemistry ; 186: 112745, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33845184

RESUMO

Phytochemical investigation of Callistemon citrinus (Curtis) Skeels (syn. Callistemon lanceolatus (Sm.) Sweet and Melaleuca citrina (Curtis) Dum.Cours.) leaves resulted in the isolation of five undescribed compounds, including one acylphloroglucinol derivative and four monoterpene galloylglucosides, in addition to 29 known diverse secondary metabolites. Interestingly, this study reports chemosystematically significant isolation of the monoterpene galloylglucosides from the genus for the first time. Furthermore, exploration of the isolated compounds as inhibitors of inflammation-related molecular targets, molecular docking studies targeting human adipocyte lipid-binding protein FABP4 (3P6H) and human nitric oxide synthase (3E7G) were carried out in order with the in vitro evaluation of the isolated compounds for their anti-microbial and inhibitory of inducible nitric oxide synthase (iNOS) activities. Molecular docking studies revealed that eighteen compounds showed lower docking scores than ibuprofen, the native ligand in the crystal structure 3P6H, and nine compounds showed lower docking scores than AR-C95791, the native ligand in the binding site of 3E7G. Additionally, in vitro studies revealed that seven compounds showed moderate iNOS inhibitory activity. They also were moderately cytotoxic to HepG2, LLC-PK1 and Vero cells. Pulverulentone A showed moderate antibacterial activity against MRSA (IC50 22.2 µM) and antifungal activity against C. neoformans, while corosolic acid showed strong antibacterial activity against VRE (IC50 15.9 µM).Thus, the in silico and in vitro studies indicated that some isolated compounds hold potentials as inhibitors of iNOS activity and anti-microbial agents.


Assuntos
Myrtaceae , Animais , Chlorocebus aethiops , Simulação de Acoplamento Molecular , Óxido Nítrico Sintase Tipo II , Folhas de Planta , Células Vero
10.
Phytochemistry ; 189: 112828, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34174637

RESUMO

Simple isoquinoline alkaloids (heliamine, dehydroheliamine), a phthalide isoquinoline alkaloid noscapine, and an aporphine alkaloid boldine are biosynthetically derived from an amino acid tyrosine. These substrates and a simple synthetic isoquinoline alkaloid (2-acetyl-7-amino-1,2,3,4-tetrahydroisoquinoline) contain an isoquinoline nucleus. The biotransformation of these substrates via reduction, oxidation, hydroxylation, and N-oxidation reactions with different microorganism produced nine metabolites, namely: N-(2-acetyl-1,2,3,4-tetrahydroisoquinolin-7-yl) acetamide (Metabolite 1), heliamine N-oxide (Metabolite 2), 6,7-dimethoxyisoquinoline (Metabolite 3), 3,4-dihydro-6,7-dimethoxy isoquinolin-1-one (Metabolite 4), heliamine (Metabolite 5), dehydroheliamine N-oxide (Metabolite 6), cotarnine (Metabolite 7), 5-hydroxy cotarnine (Metabolite 8), and boldine N-oxide (Metabolite 9). Primarily, the metabolites are structurally elucidated by one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) analyses, and high-resolution electrospray ionization mass spectrometry (HR-ESIMS). Furthermore, the substrates and their isolated metabolites are evaluated in vitro for their anti-inflammatory, antimicrobial, cytotoxicity, and anticancer activities. The in vitro studies reveal that some of the isolated compounds are potential as anti-inflammatory, antitumor, and antimicrobial leads.


Assuntos
Alcaloides , Benzilisoquinolinas , Alcaloides/farmacologia , Benzilisoquinolinas/farmacologia , Isoquinolinas/farmacologia , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
11.
J AOAC Int ; 103(1): 103-116, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31558179

RESUMO

BACKGROUND: Recently, there is a growing interest in quality by design (QbD) in the dietary supplements industry. OBJECTIVE: Effective QbD implementation necessitates a comprehensive understanding of multiple factors such as; the relationship between the critical qualities attributes (CQAs) and the scientific properties of the dietary supplement, the relationship between the manufacturing process, CQAs and the variability in raw materials. There are still two critical challenging concerns to be addressed in the implementation of QbD for herbal drugs. First, the quality variation of botanical raw materials and second, the difficulty in defining the satisfactory ranges of CQAs. METHOD: In order to tackle these challenges, this review provides a snapshot of the numerous techniques that can be used in the identification and characterization of the botanical raw materials, therefore, will help in the successful QbD implementation for botanicals and dietary supplements. CONCLUSIONS: In order to implement this approach and to be considered in the current dietary supplement regulations, fruitful discussions and collaborations between academia, industry and regulatory agencies are required.


Assuntos
Suplementos Nutricionais
12.
Phytomedicine ; 60: 153010, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31301970

RESUMO

BACKGROUND: Moringa oleifera Lam. is known as a drumstick tree that is widely cultivated in various subtropical and tropical provinces. Previous studies indicated that both aqueous and methanolic extracts of M. oleifera leaves have potent inhibitory effects on two major drug metabolizing Cytochrome P450 enzymes, namely, CYP3A4 and CYP2D6. PURPOSE: The current study was aimed to isolate the secondary metabolites from M. oleifera and investigate their cytotoxicity and inhibitory effects on CYP3A4 and CYP2D6 to assess their herb-drug interaction (HDI) potential. METHODS: Chemical structure elucidation was achieved by interpreting the spectroscopic data (UV, IR, 1D, and 2D NMR experiments), confirming by HR-ESI-MS, and comparing with the previously reported data in the literature. All the isolates were evaluated for their cytotoxicity against a panel of cell lines (SK-MEL, KB, BT-549, SK-OV-3, VERO, LLC-PK1, and HepG2) and inhibition of two principal CYP isozymes (CYP3A4 and CYP2D6). RESULTS: Phytochemical investigation of M. oleifera leaves resulted in the isolation and characterization of one new compound, namely omoringone (1), along with twelve known secondary metabolites (2-13) belonging to several chemical classes including flavonoids, terpenoids, lignans, and phenylalkanoids. A plausible biosynthetic pathway for compound 1 was provided. Because of the low isolation yield and limited supply, omoringone (1) and niazirin (12) were successively synthesized. No cytotoxicity was observed on any of the tested cell lines up to 50 µM. The extract exhibited an inhibitory effect on CYP3A4 isoform (IC50 = 52.5 ±â€¯2.5 µg/ml). Among the isolates, 1-4 and 7-9 inhibited CYP3A4 with the IC50 values ranging from 41.5 to 100 µM with no remarkable effect on CYP2D6 isozyme. CONCLUSION: This work aided in ascertaining components of M. oleifera contributing to CYP3A4 inhibition exhibited by the extract using an in vitro assay. Nonetheless, further studies are warranted to determine the bioavailability of the phytochemicals and extrapolate these findings in more physiologically relevant conditions to further establish the clinical relevance of in vitro observations.


Assuntos
Citocromo P-450 CYP2D6/efeitos dos fármacos , Citocromo P-450 CYP3A/efeitos dos fármacos , Interações Ervas-Drogas , Moringa oleifera/química , Extratos Vegetais/farmacologia , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A , Humanos , Isoenzimas/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Árvores
13.
Future Sci OA ; 3(1): FSO162, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28344826

RESUMO

AIM: This study evaluated the potential of bone marrow derived mesenchymal stem cells (MSCs) to regulate cytokines and remodel the lung induced by lipopolysaccharide (LPS; O-antigen). MATERIALS & METHODS: A group of mice (n = 21) was inoculated intraperitoneally with one dose 0.1 ml containing 0.025 mg LPS/mouse, and another treated intravenously with one dose of labeling bone marrow derived MSCs at 7.5 × 105 cell/mouse 4 h after LPS injection. All animals were sacrificed on the 1st, 7th and 14th days post-injection. RESULTS: MSCs increased the level of IL-10 with suppression of TNF-α, decrease of collagen fibers and renewal of alveolar type I cells, together with lung tissue remodeling. CONCLUSION: MSCs were shown to modulate inflammatory cytokines (TNF-α and IL-10) and to differentiate into alveolar type I cells, which prevented fibrosis in lung tissue from LPS-treated mice.

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