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1.
Int J Pharm X ; 5: 100174, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36908304

RESUMO

The most prevalent conditions among ocular surgery and COVID-19 patients are fungal eye infections, which may cause inflammation and dry eye, and may cause ocular morbidity. Amphotericin-B eye drops are commonly used in the treatment of ocular fungal infections. Lactoferrin is an iron-binding glycoprotein with broad-spectrum antimicrobial activity and is used for the treatment of dry eye, conjunctivitis, and ocular inflammation. However, poor aqueous stability and excessive nasolacrimal duct draining impede these agens' efficiency. The aim of this study was to examine the effect of Amphotericin-B, as an antifungal against Candida albicans, Fusarium, and Aspergillus flavus, and Lactoferrin, as an anti-inflammatory and anti-dry eye, when co-loaded in triblock polymers PLGA-PEG-PEI nanoparticles embedded in P188-P407 ophthalmic thermosensitive gel. The nanoparticles were prepared by a double emulsion solvent evaporation method. The optimized formula showed particle size (177.0 ± 0.3 nm), poly-dispersity index (0.011 ± 0.01), zeta-potential (31.9 ± 0.3 mV), and entrapment% (90.9 ± 0.5) with improved ex-vivo pharmacokinetic parameters and ex-vivo trans-corneal penetrability, compared with drug solution. Confocal laser scanning revealed valuable penetration of fluoro-labeled nanoparticles. Irritation tests (Draize Test), Atomic force microscopy, cell culture and animal tests including histopathological analysis revealed superiority of the nanoparticles in reducing signs of inflammation and eradication of fungal infection in rabbits, without causing any damage to rabbit eyeballs. The nanoparticles exhibited favorable pharmacodynamic features with sustained release profile, and is neither cytotoxic nor irritating in-vitro or in-vivo. The developed formulation might provide a new and safe nanotechnology for treating eye problems, like inflammation and fungal infections.

2.
Chemosphere ; 316: 137845, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36649894

RESUMO

Plastic waste (microplastics) is one of the primary sources of environmental pollutants, serving as a reservoir for them. In this study, previously isolated and screened polymer-degrading bacteria (B. subtilis V8, P. aminophilusB1 4-, P. putida C 2 5, P. aeruginosa V1, and A. calcoaceticus V4) were utilised to examine the biodegradation of LDPE (low-density polyethylene) microplastics. Response surface methodology (RSM) was used to optimize the physicochemical growth parameters (pH, temperature, and ammonium sulphate concentration). By using the polyphasic approach, including CO2 estimation, weight loss analysis, scanning electron microscopy (SEM), fourier transform infrared (FT-IR) spectroscopy, and electrical conductivities examine the plastic biodegradability. After four months, all biodegradable plastic samples were evaluated. When compared to the other tested cultures, P. aeruginosa V1 showed the most significant degradation (CO2evolution of 8.86 g.l-l and percentage weight loss of 18.21 %) with increased electrical conductivity, followed by B. subtilis V8 (CO2 evolution of 8.10 g.l-l and percentage weight loss of 16.12 %), A. calcoaceticus V4 (CO2 evolution of 7.21 g.l-l and percentage weight loss of 15.44 %), P. putida C 2-5 (CO2 evolution of 5.76 g.l-l and percentage weight loss of 13.30 %), and P. aminophilus B1 4- (CO2 evolution of 5.62 g.l-l and percentage weight loss of 11.72 %). The deteriorated materials' exterior modifications (surface alteration) were also examined using SEM analysis, and the chemical bonding alterations (bond vibration-bending) were determined using FT-IR spectroscopy.


Assuntos
Plásticos , Polietileno , Polietileno/química , Plásticos/metabolismo , Microplásticos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Dióxido de Carbono/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental
3.
Fuel (Lond) ; 331: 125720, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36033729

RESUMO

Globally, the demand for masks has increased due to the COVID-19 pandemic, resulting in 490,201 tons of waste masks disposed of per month. Since masks are used in places with a high risk of virus infection, waste masks retain the risk of virus contamination. In this study, a 1 kg/h lab-scale (diameter: 0.114 m, height: 1 m) bubbling fluidized bed gasifier was used for steam gasification (temperature: 800 °C, steam/carbon (S/C) ratio: 1.5) of waste masks. The use of a downstream reactor with activated carbon (AC) for tar cracking and the enhancement of hydrogen production was examined. Steam gasification with AC produces syngas with H2, CO, CH4, and CO2 content of 38.89, 6.40, 21.69, and 7.34 vol%, respectively. The lower heating value of the product gas was 29.66 MJ/Nm3 and the cold gas efficiency was 74.55 %. This study showed that steam gasification can be used for the utilization of waste masks and the production of hydrogen-rich gas for further applications.

4.
Food Chem (Oxf) ; 5: 100145, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36573108

RESUMO

Galactosyltransferase (GalT) is an important enzyme in synthesizing exopolysaccharide (EPS), the major polymer of biofilms protecting cells from severe conditions. However, the contribution to, and regulatory mechanism of GalT, in stressor resistance are still unclear. Herein, we successfully overexpressed GalT in Lactobacillus acidophilus NCFM by genetic engineering. The GalT activity and freeze-drying survival rate of the recombinant strain were significantly enhanced. The EPS yield also increased by 17.8%, indicating a positive relationship between freeze-drying resistance and EPS. RNA-Seq revealed that GalT could regulate the flux of the membrane transport system, pivotal sugar-related metabolic pathways, and promote quorum sensing to facilitate EPS biosynthesis, which enhanced freeze-drying resistance. The findings concretely prove that the mechanism of GalT regulating EPS biosynthesis plays an important role in protecting lactic acid bacteria from freeze-drying stress.

5.
Food Chem X ; 13: 100211, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35498979

RESUMO

A water-soluble heteropolysaccharide (SGP2-1) was purified from Suillus granulatus fruiting bodies by anion-exchange chromatography and gel permeation chromatography. The structural characteristics were analyzed by high-performance gel permeation chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. The immunostimulatory activity was investigated using RAW 264.7 macrophages. Results showed that SGP2-1 with weight average molecular weight of 150.75 kDa was composed of mannose, glucose, and xylose. The backbone of SGP2-1 was mainly composed of â†’ 4)-α-Glcp-(1→, and the terminal group α-d-Glcp â†’ was linked to the main chain by O-6 position. SGP2-1 could significantly enhance pinocytic capacity, reactive oxygen species production, and cytokines secretion. SGP2-1 exerted immunomodulatory effects through interacting with toll-like receptor 2, and activating mitogen-activated protein kinase, phosphatidylinositol-3-kinase/protein kinase B, and nuclear factor-kappa B signaling pathways. These findings indicated that SGP2-1 could be explored as a potential immunomodulatory agent for application in functional foods.

6.
J Tradit Complement Med ; 11(6): 481-492, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765512

RESUMO

BACKGROUND AND AIM: Epithelial ovarian cancer has the deadliest prognosis amongst gynaecological cancers, warranting an unmet need for newer drug targets. Based on its anticancer as well as abortifacient potential, Moringa oleifera Lam. root was hypothesized to have some implications in follicle stimulating hormone receptor (FSHR) dependent cancers like epithelial ovarian cancer. EXPERIMENTAL PROCEDURE: Effect of Moringa oleifera Lam. root extract (MRE) was studied in epithelial ovarian cancer cell line through in vitro studies viz. MTT assay, clonogenic assay, cell cycle analysis, flow cytometry, western blot analysis, immunocytochemical analysis of FSHRand c-Myc expression and in vivo studies viz. effect of MRE in mice model of ovarian carcinoma. The structure of the active compound of MRE was elucidated following solvent extraction, purification through column chromatography, preparative TLC and bioactivity guided structural identification through 1H-NMR, 13C-NMR, DEPT-135, ESIMS,FT-IR spectrophotometry, UV-vis-NIR spectrophotometry and DFT study. RESULTS AND CONCLUSION: Crude MRE displayed cytotoxic activity, induced apoptosis, and attenuated expression of FSHR and c-Myc in ovarian cancer cell line OAW42. MRE also attenuated expression of CD31, FSHR, and c-Myc in tumour xenograft mouse model. Finally, the active compound purified from ethyl acetate-n-hexane subfraction ofMRE, that attenuated viability of ovarian carcinoma cell lines and reduced FSHR and c-Myc expression, was identified as a naturally hydrated-trifattyglyceride, showing aDFT-optimized folded amphipathic structure for easy transportation through hydrophilic and hydrophobic regions in a biological system, indicating its immense therapeutic relevance in epithelial ovarian carcinoma.

7.
Toxicol Rep ; 8: 1721-1728, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692422

RESUMO

The present study sought to investigate the effects of amino-functionalized tannic acid-templated mesoporous silica nanoparticles (TA-MS-NH2 NPs) on giving rats protection against iron-induced liver toxicity. To this end, the TA-MS-NH2 NPs were characterized using field-emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR). Moreover, 50 Wistar rats were randomly divided into one control group (group 1) and four experimental groups (groups 2- 5) (n = 10), each of which received 100 mg/kg oral normal saline and FeSO4, respectively. Then, post-exposure hepatotoxicity and oxidative stress markers were measured in two intervals, i.e., after 4 and 24 h, followed by the measurement of the acute iron toxicity. Furthermore, hepatotoxicity markers, including the alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total antioxidant capacity (TAC), were measured via Ferric Reducing Antioxidant Power (FRAP) and 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) assays. Also, malondialdehyde (MDA), total thiol groups, advanced oxidation protein products (AOPP), and nitrite/nitrate (NOx) levels were measured as oxidative stress markers in the serum samples. The results indicated that oral administration of iron significantly elevated the liver enzymes and altered the level of oxidative stress markers. It was also found that treatment with TA-MS-NH2 NPs meaningfully protected against hepatotoxicity, decreased ALT, AST, ALP, and significantly improved oxidative stress markers by decreasing MDA, AOPP, and NOx levels and increasing TAC and thiol group contents, proving that TA-MS-NH2 NPs could protect rats against iron-induced acute liver toxicity through their antioxidant features.

8.
Saudi J Biol Sci ; 28(8): 4311-4317, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34354413

RESUMO

Asthma as chronic airway disease has high prevalence in children and imbalance of Th1/Th2 is a critical mechanism in pathogenesis of the asthma. Baicalein as a cell protective and anti-inflammatory flavonoid may have anti-asthma effect. Therefore, for better using lung, baicalein was used in chitosan-nanoparticle as anti-asthma treatment. Baicalein was loaded and encapsulated in chitosan nanoparticle. The morphology, physical characters (particle size, zeta potential and FT-IR) were analyzed. Drug encapsulation and loading capacity, accumulative release-time were studied. After asthma model producing, the mice were treated with L-B-NP and E-B-NP. At least, MCh challenge test, Cytokines measurement and Lung Histopathology were done. Nanoparticles had average size 285 ± 25 nm with negative charge -2.5 mV. The L-B-NP decreased penh value and E-B-NP decreased inflammation. Both nanoparticles increased IL-12 and decreased IL-5. Also, L-B-NP decreased mucus secretion in bronchi. L-B-NP and E-B-NP control immune-allergo-inflammatory response of asthma. L-B-NP controlled AHR and E-B-NP controlled inflammation that can be used as controlling anti-asthma drug.

9.
Mater Today Bio ; 11: 100114, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34169268

RESUMO

Materials made of recombinant spider silk proteins are promising candidates for cardiac tissue engineering, and their suitability has so far been investigated utilizing primary rat cardiomyocytes. Herein, we expanded the tool box of available spider silk variants and demonstrated for the first time that human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes attach, contract, and respond to pharmacological treatment using phenylephrine and verapamil on explicit spider silk films. The hiPSC-cardiomyocytes contracted for at least 14 days on films made of positively charged engineered Araneus diadematus fibroin 4 (eADF4(κ16)) and three different arginyl-glycyl-aspartic acid (RGD)-tagged spider silk variants (positively or negatively charged and uncharged). Notably, hiPSC-cardiomyocytes exhibited different morphologies depending on the spider silk variant used, with less spreading and being smaller on films made of eADF4(κ16) than on RGD-tagged spider silk films. These results indicate that spider silk engineering is a powerful tool to provide new materials suitable for hiPSC-based cardiac tissue engineering.

10.
Comput Struct Biotechnol J ; 19: 2938-2949, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34136093

RESUMO

The Nerve Growth Factor (NGF) neurotrophin acts in the maintenance and growth of neuronal populations. Despite the detailed knowledge of NGF's role in neuron physiology, the structural and mechanistic determinants of NGF bioactivity modulated by essential endogenous ligands are still lacking. We present the results of an integrated structural and advanced computational approach to characterize the extracellular ATP-NGF interaction. We mapped by NMR the interacting surface and ATP orientation on NGF and revealed the functional role of this interaction in the binding to TrkA and p75NTR receptors by SPR. The role of divalent ions was explored in conjunction with ATP. Our results pinpoint ATP as a likely transient molecular modulator of NGF signaling, in health and disease states.

11.
Acta Pharm Sin B ; 11(4): 989-1002, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33996411

RESUMO

The aim was to evaluate the potential of mucus-permeating nanoparticles for the oral administration of insulin. These nanocarriers, based on the coating of zein nanoparticles with a polymer conjugate containing PEG, displayed a size of 260 nm with a negative surface charge and an insulin payload of 77 µg/mg. In intestinal pig mucus, the diffusivity of these nanoparticles (PPA-NPs) was found to be 20-fold higher than bare nanoparticles (NPs). These results were in line with the biodistribution study in rats, in which NPs remained trapped in the mucus, whereas PPA-NPs were able to cross this layer and reach the epithelium surface. The therapeutic efficacy was evaluated in Caenorhabditis elegans grown under high glucose conditions. In this model, worms treated with insulin-loaded in PPA-NPs displayed a longer lifespan than those treated with insulin free or nanoencapsulated in NPs. This finding was associated with a significant reduction in the formation of reactive oxygen species (ROS) as well as an important decrease in the glucose and fat content in worms. These effects would be related with the mucus-permeating ability of PPA-NPs that would facilitate the passage through the intestinal peritrophic-like dense layer of worms (similar to mucus) and, thus, the absorption of insulin.

12.
Saudi J Biol Sci ; 28(4): 2229-2235, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33935565

RESUMO

Cheeseweed mallow (Malva parviflora L.) was used to biosynthesize silver nanoparticles. The biosynthesized silver nanoparticles were classified by UV-vis Spectroscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). The shape and size distribution were visualized by Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), and Zeta potential analysis. The chemical composition of M. parviflora leaf extract was identified by Gas Chromatography and Mass Spectroscopy (GC/MS). Finally, in vitro antifungal assay was done to assess the potential of biosynthesized silver nanoparticles and crude leaf extract of M. parviflora for inhibiting the mycelial growth of phytopathogenic fungi. The UV-vis analysis manifests the formation of silver nanoparticles. FTIR analysis established that chemicals of the leaf extract stabilized the biosynthesized silver nanoparticles by binding with the free silver ions. The TEM, FE-SEM and zeta potential analyzer confirmed that the biosynthesized silver nanoparticles were mostly spherical with an average diameter of 50.6 nm. The biosynthesized silver nanoparticles and leaf extract of M. parviflora effectively mitigate the mycelial growth of Helminthosporium rostratum, Fusarium solani, Fusarium oxysporum, and Alternaria alternata. The maximum reduction in mycelial growth by biosynthesized nanoparticles was observed against H. rostratum (88.6%). Whereas, the leaf extract of M. parviflora was most effective against F. solani (65.3%). Thus, the biosynthesis of nanoparticle assisted by M. parviflora is a feasible and eco-friendly method for the synthesis of silver nanoparticles. Further the silver nanoparticles and leaf extract of M. parviflora could be explored for the development of the fungicide.

13.
Coord Chem Rev ; 426: 213544, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32981945

RESUMO

Progress in metal-organic frameworks (MOFs) has advanced from fundamental chemistry to engineering processes and applications, resulting in new industrial opportunities. The unique features of MOFs, such as their permanent porosity, high surface area, and structural flexibility, continue to draw industrial interest outside the traditional MOF field, both to solve existing challenges and to create new businesses. In this context, diverse research has been directed toward commercializing MOFs, but such studies have been performed according to a variety of individual goals. Therefore, there have been limited opportunities to share the challenges, goals, and findings with most of the MOF field. In this review, we examine the issues and demands for MOF commercialization and investigate recent advances in MOF process engineering and applications. Specifically, we discuss the criteria for MOF commercialization from the views of stability, producibility, regulations, and production cost. This review covers progress in the mass production and formation of MOFs along with future applications that are not currently well known but have high potential for new areas of MOF commercialization.

14.
Saudi J Biol Sci ; 27(4): 1024-1040, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32256163

RESUMO

AIM OF THE STUDY: 5-Fluorouracil (5-FU) can't be given orally because of very low bioavailability and produces serious adverse effects. Therefore, the main objective of this research is to develop, evaluate, and comparative effects by different nanoformulations of topical application on chemoprevention of skin cancer in different types of skin. MATERIAL AND METHODS: Castor oil (oil), Transcutol HP (surfactant), and Polyethylene glycol (PEG)-400 (co-surfactant) have taken on the basis of nonionic property and highest nanoemulsion (NE)-region. Aqueous micro titration method with ultra-sonication method (based on high energy) was used for the preparation of 5-FU-NE. Optimized-5-FU-NE was stable thermodynamically, and their characterizations was performed on the basis of globule size, zeta potential, refractive index, and viscosity. Optimized-NE has been converted into 5-FU-NE-Gel with the help of Carbopol® 934 and also performed their permeation studies in the different skins (cow, goat, and rat, ex vivo) using Logan transdermal diffusion cell (DHC-6T). Optimized-5-FU-NE and 5-FU-NE-Gel were evaluated cytotoxic studies (in vitro) on the melanoma cell lines. RESULTS: The permeation of 5-FU from 5-FU-NE-Gel nanoformulation for rat skin model was 1.56 times higher than the 5-FU-NE and 12.51 times higher than the 5-FU-S for the cow and goat skin model. The values of steady state flux and permeability coefficient for 5-FU-NE-Gel of rat skin were higher i.e. 12.0244 ±â€¯1.12 µgcm-2h-1 and 1.2024 ±â€¯0.073 × 10-2 µg cm-2h-1, respectively. Optimized-5-FU-NE and 5-FU-NE-Gel nanoformulation were found to be physically stable. SK-MEL-5 cancer cells have showed the results based on cytotoxicity studies (in vitro) that 5-FU as Optimized-5-FU-NE-Gel is much more efficacious than 5-FU-NE followed by free 5-FU. Localization of 5-FU from 5-FU-NE-Gel was higher with higher permeation in rat skin. CONCLUSION: 5-FU-NE-Gel is found to be for the better to treatment of cutaneous malignancies. It can be developed 5-FU-NE-Gel could be a promising vehicle for the skin cancer chemoprevention.

15.
Acta Pharm Sin B ; 9(1): 19-35, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30766775

RESUMO

In recent years, the coamorphous drug delivery system has been established as a promising formulation approach for delivering poorly water-soluble drugs. The coamorphous solid is a single-phase system containing an active pharmaceutical ingredient (API) and other low molecular weight molecules that might be pharmacologically relevant APIs or excipients. These formulations exhibit considerable advantages over neat crystalline or amorphous material, including improved physical stability, dissolution profiles, and potentially enhanced therapeutic efficacy. This review provides a comprehensive overview of coamorphous drug delivery systems from the perspectives of preparation, physicochemical characteristics, physical stability, in vitro and in vivo performance. Furthermore, the challenges and strategies in developing robust coamorphous drug products of high quality and performance are briefly discussed.

16.
J Biomol Struct Dyn ; 36(12): 3172-3183, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28934908

RESUMO

Human IgG is a defence protein and quite reactive to dicarbonyls. In this study, methylglyoxal-induced modification of IgG was examined by various biochemical and biophysical methods. The methylglyoxal-induced changes in IgG were monitored by UV-visible and fluorescence spectroscopy, Fourier transform infrared spectroscopy, 1-anilinonaphthalene-8-sulfonic acid (ANS), and thermal denaturation studies. Aggregate formation was studied by Thioflavin T (ThT), Congo red (CR) and scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Spectroscopic studies suggested gross changes in MGO-modified IgG. Fluorogenic AGEs appeared during modification and the MGO-modified IgG gained thermostability. The reaction produced oxidative stress in the medium because carbonyl content increased manifold and sulfhydryl groups decreased. Enhanced binding of the MGO-modified IgG by Congo red and Thioflavin T suggests crosslinking and aggregation. This was supported by SEM and TEM results.


Assuntos
Fenômenos Biofísicos , Imunoglobulina G/ultraestrutura , Aldeído Pirúvico/química , Benzotiazóis/química , Glicosilação , Humanos , Imunoglobulina G/química , Imunoglobulina G/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Des Monomers Polym ; 20(1): 406-418, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29491812

RESUMO

Sharply thermo- and pH-responsive pentablock terpolymer with a core-shell-corona structure was prepared by RAFT polymerization of N-isopropylacrylamide and methacrylic acid monomers using PEG-based benzoate-type of RAFT agent. The PEG-based RAFT agent could be easily synthesized by dihydroxyl-capped PEG with 4-cyano-4-(thiobenzoyl) sulfanylpentanoic acids, using esterification reaction. This pentablock terpolymer was characterized by 1H NMR, FT-IR, and GPC. The PDI was obtained by GPC, indicating that the molecular weight distribution was narrow and the polymerization was well controlled. The thermo- and pH-responsive micellization of the pentablock terpolymer in aqueous solution was investigated using fluorescence spectroscopy technique, UV-vis transmittance, and TEM. The LCST of pentablock terpolymer increased (over 50 °C) compared to the NIPAM homopolymer (~32 °C), due to the incorporation of the hydrophilic PEG and PMA blocks in pentablock terpolymer (PNIPAM block as the core, PEG the block and the hydrophilic PMA block as the shell and the corona). Also, pH-dependent phase transition behavior shows at a pH value of about ~5.8, according to pKa of MAA. Thus, in acidic solution at room temperature, the pentablock terpolymer self-assembled to form core-shell-corona micelles, with the hydrophobic PMA block as the core, the PNIPAM block and the hydrophilic PEG block as the shell and the corona, respectively.

18.
Mol Metab ; 5(12): 1162-1174, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27900259

RESUMO

OBJECTIVE: Gut microbiota may promote positive energy balance; however, germfree mice can be either resistant or susceptible to diet-induced obesity (DIO) depending on the type of dietary intervention. We here sought to identify the dietary constituents that determine the susceptibility to body fat accretion in germfree (GF) mice. METHODS: GF and specific pathogen free (SPF) male C57BL/6N mice were fed high-fat diets either based on lard or palm oil for 4 wks. Mice were metabolically characterized at the end of the feeding trial. FT-ICR-MS and UPLC-TOF-MS were used for cecal as well as hepatic metabolite profiling and cecal bile acids quantification, respectively. Hepatic gene expression was examined by qRT-PCR and cecal gut microbiota of SPF mice was analyzed by high-throughput 16S rRNA gene sequencing. RESULTS: GF mice, but not SPF mice, were completely DIO resistant when fed a cholesterol-rich lard-based high-fat diet, whereas on a cholesterol-free palm oil-based high-fat diet, DIO was independent of gut microbiota. In GF lard-fed mice, DIO resistance was conveyed by increased energy expenditure, preferential carbohydrate oxidation, and increased fecal fat and energy excretion. Cecal metabolite profiling revealed a shift in bile acid and steroid metabolites in these lean mice, with a significant rise in 17ß-estradiol, which is known to stimulate energy expenditure and interfere with bile acid metabolism. Decreased cecal bile acid levels were associated with decreased hepatic expression of genes involved in bile acid synthesis. These metabolic adaptations were largely attenuated in GF mice fed the palm-oil based high-fat diet. We propose that an interaction of gut microbiota and cholesterol metabolism is essential for fat accretion in normal SPF mice fed cholesterol-rich lard as the main dietary fat source. This is supported by a positive correlation between bile acid levels and specific bacteria of the order Clostridiales (phylum Firmicutes) as a characteristic feature of normal SPF mice fed lard. CONCLUSIONS: In conclusion, our study identified dietary cholesterol as a candidate ingredient affecting the crosstalk between gut microbiota and host metabolism.


Assuntos
Gorduras na Dieta/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Animais , Colesterol/metabolismo , Colesterol na Dieta/metabolismo , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/metabolismo , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
19.
Saudi Pharm J ; 24(6): 689-697, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27829812

RESUMO

The aim of the paper was to formulate a combined oral dosage form of rosuvastatin calcium and amlodipine besylate and to develop and validate an analytical method to be adopted for both routine quality control assay and in vitro dissolution studies of the formulation. The proposed combination formulation has shown compatibility with the chosen excipients, verified through FT-IR study. A novel gradient RP-HPLC method was developed and validated according to the ICH guideline which was found to be suitable for the simultaneous estimation of rosuvastatin calcium and amlodipine besylate from the formulation. The retention time of 2.7 and 6.08 min allows the analysis of large amount of samples with less mobile phase which makes the method economic. The dissolution profiles of both the drugs in different dissolution medium were encouraging which makes the combination formulation of rosuvastatin calcium and amlodipine besylate superior and effective in achieving patient compliance.

20.
Acta Pharm Sin B ; 6(3): 234-42, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27175335

RESUMO

Bifendate, a synthetic anti-hepatitis drug, exhibits polycrystalline mode phenomena with 2 polymorphs reported (forms A and B). Single crystals of the known crystalline form B and 3 new crystallosolvates involving bifendate solvated with tetrahydrofuran (C), dioxane (D), and pyridine (E) in a stoichiometric ratio of 1:1 were obtained and characterized by X-ray crystallography, thermal analysis, and Fourier transform infrared (FT-IR) spectroscopy. The differences in molecular conformation, intermolecular interaction and crystal packing arrangement for the four polymorphs were determined and the basis for the polymorphisms was investigated. The rotation of single bonds resulted in different orientations for the biphenyl, methyl ester and methoxyl groups. All guest solvent molecules interacted with the host molecule via an interesting intercalative mode along the [1 0 0] direction in the channel formed by the host molecules through weak aromatic stacking interactions or non-classical hydrogen bonds, of which the volume and planarity played an important role in the intercalation of the host with the guest. The incorporation of solvent-augmented rotation of the C-C bond of the biphenyl group had a striking effect on the host molecular conformation and contributed to the formation of bifendate polymorphs. Moreover, the simulated powder X-ray diffraction (PXRD) patterns for each form were calculated on the basis of the single-crystal data and proved to be unique. The single-crystal structures of the four crystalline forms are reported in this paper.

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