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Beneficial effects of baicalein on a model of allergic rhinitis

Abstract

Allergic rhinitis (AR) is a common disease that causes severe inflammation and even disabilities. Previous studies have reported baicalein to have an anti-inflammatory effect. However, the pharmacological action of baicalein on anaphylaxis has not been clarified yet. This study assessed the in vivo protective effect of baicalein post-treatment in an ameliorating ovalbumin (OVA)-sensitized AR rat model. Baicalein attenuated histological alterations, aberrant tissue repair and inflammation after OVA-induced AR. Baicalein reduced the frequency of nasal/ear rubs and sneezes in rats, and inhibited generation of several inflammatory cytokines (TNF-α, IL-1β, and IL-6) in both blood and nasal lavage of rats. Infiltrations of eosinophils, lymphocyte, and neutrophils were decreased in baicalein-administered rats. Furthermore, baicalein inhibited the expression of STAT3 phosphorylation in the nasal mucosa. In summary, baicalein attenuated OVA-induced AR and inflammation, which suggests it as a promising therapeutic agent for the alleviation of AR-associated inflammation and pathology.

Open access
Branched PLGA derivatives with tailored drug delivery properties

Abstract

Despite several shortcomings such as extreme hydrophobicity, low drug capacity, characteristic triphasic drug release pattern with a high burst effect, poly(lactic-co-glycolic acid derivatives are widely used in drug delivery. Most frequent attempts to improve their properties are blending with other polymers or synthesis of block copolymers. We introduce a new class of branched poly(lactic-co-glycolic acid) derivatives as promising biodegradable carriers for prolonged or targeted drug release systems, employed as thin adhesive films, solid dispersions, in situ forming implants or nanoparticles. A series of poly(lactic-co-glycolic acid) derivatives with lower molar mass and star or comb architecture were synthesized by a simple, catalyst free, direct melt polycondensation method not requiring purification of the obtained sterile product by precipitation. Branching monomers used were mannitol, pentaerythritol, dipentaerythritol, tripentaerythritol and polyacrylic acid. The products were characterized by molar mass averages, average branching ratio, rheological and thermal properties.

Open access
Development and validation of a UPLC-MS method for determination of atazanavir sulfate by the “analytical quality by design” approach

Abstract

A UPLC-MS method for the estimation of atazanavir sulfate was developed using the “analytical quality by design” approach. The critical chromatographic quality attributes identified were retention time, theoretical plates and peak tailing. The critical method parameters established were percent of organic modifier, flow rate and injection volume. Optimization performed using Box-Behnken Design (BBD) established 10 % organic modifier, 0.4 mL min−1 flow rate and 6-µL injection volume as the optimum method conditions. Atazanavir sulfate eluted at 5.19 min without any interference. Method validation followed international guidelines. The method has proven linearity in the range of 10–90 µg mL−1. Recovery was between 100.2–101.0 % and precision within the accepted limits (RSD 0.2–0.7 %). LOD and LOQ were 2.68 and 8.14 µg mL−1, resp. Stress testing stability studies showed atazanavir sulfate to degrade under acidic and basic conditions. The suggested technique is simple, rapid and sustainable. It is, therefore, suggested for routine analysis of atazanavir sulfate.

Open access
Modified release of furosemide from Eudragits® and poly(ethylene oxide)-based matrices and dry-coated tablets

Abstract

Modified release of furosemide from tablet formulations is preferred by patients, because of physiological problems, acute diuresis being the most serious, compared to the forms designed for immediate release. With this in view, we aimed at achieving furosemide’s longer gastric retention and waste minimization by preparing matrix and compression coated tablets incorporating different grades of Eudragit® and poly(ethylene oxide) (PEO), polyvinylpyrrolidone (PVP) and lactose monohydrate. Dissolution profiles of the new formulations were compared with that of the main stream drug Lasix®, 40 mg tablets. The results indicate that the use of Eudragit® in conjunction with either PVP or lactose monohydrate led to a slower release rate in the intestinal fluids compared to Lasix®. Moreover, furosemide release in the intestinal pH from matrix tablets and compression coated tablets was not noticeably different. Formulations incorporating PEO led to sustained release, in intestinal fluids, which depended on the molecular weight of PEO.

Open access
Poly(3-hydroxybutyrate): Promising biomaterial for bone tissue engineering

Abstract

Poly(3-hydroxybutyrate) is a natural polymer, produced by different bacteria, with good biocompatibility and biodegradability. Cardiovascular patches, scaffolds in tissue engineering and drug carriers are some of the possible biomedical applications of poly(3-hydroxybutyrate). In the past decade, many researchers examined the different physico-chemical modifications of poly(3-hydroxybutyrate) in order to improve its properties for use in the field of bone tissue engineering. Poly(3-hydroxybutyrate) composites with hydroxyapatite and bioglass are intensively tested with animal and human osteoblasts in vitro to provide information about their biocompatibility, biodegradability and osteoinductivity. Good bone regeneration was proven when poly(3-hydroxy-butyrate) patches were implanted in vivo in bone tissue of cats, minipigs and rats. This review summarizes the recent reports of in vitro and in vivo studies of pure poly(3-hydroxy-butyrate) and poly(3-hydroxybutyrate) composites with the emphasis on their bioactivity and biocompatibility with bone cells.

Open access
Prediction of drug-drug plasma protein binding interactions of resveratrol in combination with celecoxib and leflunomide by molecular docking combined with an ultrafiltration technique

Abstract

The present study is aimed at computational prediction of the molecular interactions between resveratrol, celecoxib, leflunomide and human serum albumin (HSA) and then investigates the plasma protein binding of resveratrol combined with celecoxib or leflunomide by an ultrafiltration technique. Molecular operating environment (MOE, 2008.10) software package was used to explore molecular interactions between the drugs and HSA. Molecular docking was adopted to predict the interactions between resveratrol and other drugs and then the ultrafiltration technique was used to verify the docking results. In in vitro experiments, a mixture of resveratrol and celecoxib or leflunomide was added to rat plasma for determination of the plasma protein binding rate. Molecular docking results have shown that resveratrol interacts with HSA mainly through hydrogen bond and π-π stacking, while celecoxib and leflunomide bind only with the hydrogen bond. Celecoxib or leflunomide, even at high tested doses, did not affect the plasma protein binding of resveratrol, thus suggesting pharmacological suitability of the investigated combinations.

Open access
Qualitative and quantitative HPLC-ELSD-ESI-MS analysis of steroidal saponins in fenugreek seed

Abstract

Fenugreek seeds are known as a source of various compounds, the most common of which are steroidal saponins. However, despite the growing interest in this plant material as a healing agent, spice and dietary supplement ingredient, the composition of Polish fenugreek seeds remains unknown. Therefore, the steroidal saponin complex in the seeds of T. foenum-graecum cultivated in Poland was qualitatively and quantitatively analyzed by the HPLC-ELSDESI-MS method. Two C-18 columns connected in series were used for the first time in analysis of fenugreek saponins and ELS detector parameters were optimized. A total of 26 furostanol saponins were revealed, of which 24 were tentatively identified. The HPLC-ELSD method developed for quantitative analysis was preliminarily validated and the determined amount of steroidal saponins in Polish fenugreek seeds was 0.14 %.

Open access
Self-microemulsifying drug delivery systems of Moringa oleifera extract for enhanced dissolution of kaempferol and quercetin

Abstract

The aim of the present study was to develop self-microemulsifying drug delivery systems (SMEDDS) of the extract of Moringa oleifera, a herbal medicinal plant. Kaempferol and quercetin, the flavonoids present in the leaf extract of M. oleifera, were chosen as markers for quantification. The optimized formulation of SMEDDS consisted of propylene glycol dicaprylocaprate, polysorbate 80, and polyethylene glycol 400 (PEG 400) in a percentage ratio of 20:60:20 (m/m). SMEDDS emulsified immediately (within 20 s) after dilution in water, resulting in transparent microemulsions with a droplet size of 49 nm. SMEDDS could increase the solubility of kaempferol and quercetin to nearly 100 % within 15 min, whereas only a 30 % improvement in solubility was achieved in the case of crude extract. These results demonstrated SMEDDS to be a promising strategy to improve the solubility of M. oleifera extract-derived drugs, which, in turn, could prove beneficial to the herbal medicine field.

Open access
Sildenafil alters biogenic amines and increases oxidative damage in brain regions of insulin-hypoglycemic rats

Abstract

The aim of the present study was to determine the effect of sildenafil on dopamine, 5-hydroxyindol acetic acid (5-HIAA) and selected biomarkers of oxidative stress in the brain of hypoglycemic rats. The animals were treated intraperitoneally as follows: group 1 (control), saline solution; group 2, insulin (10 U per rat or 50 U kg−1); group 3, insulin + single dose of sildenafil (50 U kg−1 + 50 mg kg–1); group 4, insulin + three doses of sildenafil every 24 hours (50 U kg−1 + 50 mg kg−1). In groups 2, 3 and 4, insulin was administered every 24 hours for 10 days. Blood glucose was measured after the last treatment. On the last day of the treatment, the animals´ brains were extracted to measure the levels of oxidative stress markers [H2O2, Ca2+,Mg2+-ATPase, glutathione and lipid peroxidation (TBARS)], dopamine and 5-HIAA in the cortex, striatum and cerebellum/medulla oblongata by validated methods. The results suggest that administration of insulin in combination with sildenafil induces hypoglycemia and hypotension, enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines. Administration of insulin and sildenafil promotes biometabolic responses in glucose control, namely, it induces hypoglycemia and hypotension. It also enhances oxidative damage and provokes changes in the brain metabolism of biogenic amines.

Open access
TLC-densitometric analysis of allantoin in Symphytum officinale L. roots

Abstract

A TLC-densitometric method for determination of allantoin in Symphytum officinale root was developed. Densitometric quantification of allantoin was carried out on TLC Si60 plates with butanol-50 % methanol/formic acid, 66.5:33.2:0.3 (V/V/V) as developing solvent, at a wavelength of 190 nm. The method was preliminarily validated in terms of specificity, linearity, precision, limit of detection, limit of quantification, recovery and robustness. The results of TLC quantification were compared with HPLC analysis carried out on a HILIC Luna NH2 100A column, with mobile phase consisting of acetonitrile/water 80:20 (V/V) and UV detection at 190 and 210 nm. Allantoin content was determined in two herbal products and it varied from 0.94 to 2.09 %, depending on the producer, and was in agreement with literature reports.

Open access