Deciphering the Lipid-Random Copolymer Interactions and Encoding Their Properties to Design a Hybrid System.

Lipid/copolymer colloidal systems are deemed hybrid materials with unique properties and functionalities. Their hybrid nature leads to complex interfacial phenomena, which have not been fully encoded yet, navigating their properties. Moving toward in-depth knowledge of such systems, a comprehensive investigation of them is imperative. In the present study, hybrid lipid/copolymer structures were fabricated and examined by a gamut of techniques, including dynamic light scattering, fluorescence spectroscopy, cryogenic transmission electron microscopy, microcalorimetry, and high-resolution ultrasound spectroscopy. The biomaterials that were mixed for this purpose at different ratios were 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine and four different linear, statistical (random) amphiphilic copolymers, consisting of oligo(ethylene glycol) methyl ether methacrylate as the hydrophilic comonomer and lauryl methacrylate as the hydrophobic one. The colloidal dispersions were studied for lipid/copolymer interactions regarding their physicochemical, morphological, and biophysical behavior. Their membrane properties and interactions with serum proteins were also studied. The aforementioned techniques confirmed the hybrid nature of the systems and the location of the copolymer in the structure. More importantly, the random architecture of the copolymers, the hydrophobic-to-hydrophilic balance of the nanoplatforms, and the lipid-to-polymer ratio are highlighted as the main design-influencing factors. Elucidating the lipid/copolymer interactions would contribute to the translation of hybrid nanoparticle performance and, thus, their rational design for multiple applications, including drug delivery.

Fabricating Polymer/Surfactant/Cyclodextrin Hybrid Particles for Possible Nose-to-Brain Delivery of Ropinirole Hydrochloride: In Vitro and Ex Vivo Evaluation.

Ropinirole is a non-ergolinic dopamine agonist used to manage Parkinson's disease and it is characterized by poor oral bioavailability. This study aimed to design and develop advanced drug delivery systems composed of poloxamer 407, a non-ionic surfactant (Tween 80), and cyclodextrins (methyl-ß-CD or hydroxy-propyl-ß-CD) for possible brain targeting of ropinirole after nasal administration for the treatment of Parkinson's disease. The hybrid systems were formed by the thin-film hydration method, followed by an extensive physicochemical and morphological characterization. The in vitro cytotoxicity of the systems on HEK293 cell lines was also tested. In vitro release and ex vivo mucosal permeation of ropinirole were assessed using Franz cells at 34 °C and with phosphate buffer solution at pH 5.6 in the donor compartment, simulating the conditions of the nasal cavity. The results indicated that the diffusion-controlled drug release exhibited a progressive increase throughout the experiment, while a proof-of-concept experiment on ex vivo permeation through rabbit nasal mucosa revealed a better performance of the prepared hybrid systems in comparison to ropinirole solution. The encouraging results in drug release and mucosal permeation indicate that these hybrid systems can serve as attractive platforms for effective and targeted nose-to-brain delivery of ropinirole with a possible application in Parkinson's disease. Further ex vivo and in vivo studies to support the results of the present work are ongoing.

Development of Novel Pharmaceutical Forms of the Marine Bioactive Pigment Echinochrome A Enabling Alternative Routes of Administration.

Echinochrome A (EchA), a marine bioactive pigment isolated from various sea urchin species, is the active agent of the clinically approved drug Histochrome®. EchA is currently only available in the form of an isotonic solution of its di- and tri-sodium salts due to its poor water solubility and sensitivity to oxidation. Electrospun polymeric nanofibers have lately emerged as promising drug carriers capable of improving the dissolution and bioavailability of drugs with limited water solubility. In the current study, EchA isolated from sea urchins of the genus Diadema collected at the island of Kastellorizo was incorporated in electrospun micro-/nanofibrous matrices composed of polycaprolactone and polyvinylpyrrolidone in various combinations. The physicochemical properties of the micro-/nanofibers were characterized using SEM, FT-IR, TGA and DSC analyses. The fabricated matrices exhibited variable dissolution/release profiles of EchA, as evidenced in in vitro experiments using gastrointestinal-like fluids (pH 1.2, 4.5 and 6.8). Ex vivo permeability studies using the EchA-loaded micro-/nanofibrous matrices showed an increased permeation of EchA across the duodenum barrier. The results of our study clearly show that electrospun polymeric micro-/nanofibers represent promising carriers for the development of new pharmaceutical formulations with controlled release, as well as increased stability and solubility of EchA, suitable for oral administration, while offering the potential for targeted delivery.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin.

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Development of a Novel Apigenin Dosage form as a Substitute for the Modern Triple Antithrombotic Regimen.

The simultaneous administration of three antiplatelet agents has been proposed as an efficient strategy for the secondary prevention of atherothrombotic events and is included in the European guidelines. However, this strategy presented an increased risk of bleeding; therefore, the identification of new antiplatelet agents, with improved efficacy and diminished side effects, is of great importance. In silico studies, UPLC/MS Q-TOF plasma stability, in vitro platelet aggregation experiments, and pharmacokinetic studies were exploited. In the present study, it has been predicted that the flavonoid apigenin could target different platelet activation pathways, including P2Y12, protease-activated receptor-1 (PAR-1), and cyclooxygenase 1 (COX-1). To enhance apigenin's potency, hybridization with docosahexaenoic acid (DHA) was performed, as fatty acids have illustrated potent efficacy against cardiovascular diseases (CVDs). The new molecular hybrid, termed 4'-DHA-apigenin, demonstrated enhanced inhibitory activity against platelet aggregation induced by thrombin receptor activator peptide-6 (TRAP-6), adenosine diphosphate (ADP), and arachidonic acid (AA), with respect to the parent apigenin. The 4'-DHA-apigenin hybrid illustrated an almost 2-fold enhanced inhibitory activity, with respect to apigenin, and an almost 3-fold enhanced inhibitory activity, with respect to DHA, for the ADP-induced platelet aggregation. Additionally, the hybrid presented a more than 12-fold enhanced inhibitory activity with respect to DHA for the TRAP-6 induced platelet aggregation. Furthermore, a 2-fold enhanced inhibitory activity was recorded for the 4'-DHA-apigenin hybrid for the AA-induced platelet aggregation with respect to apigenin. To surmount the reduced LC-MS based plasma stability, a novel dosage form in olive oil has been developed. The 4'-DHA-apigenin olive oil-based formulation presented an enhanced antiplatelet inhibitory effect in three activation pathways. To further explore the pharmacokinetic profile of 4'-DHA-apigenin in olive oil formulations, a UPLC/MS Q-TOF protocol has been established to quantify the serum levels of apigenin after oral administration to C57BL/6J wild type mice. The olive oil-based formulation of 4'-DHA-apigenin demonstrated an increase in apigenin bioavailability of 262 %. This study may offer a new therapeutic strategy tailored to improve the treatment of CVDs.

Exercise training inhibits atherosclerosis progression and reduces VE-cadherin levels within atherosclerotic plaques in hypercholesterolemic mice.

Vascular endothelial-cadherin (VE-cadherin), matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) have emerged as key-factors of atherogenesis. The aim of this study was to evaluate the effects of exercise training (ET) on those key-factors in relation to the progression of atherosclerotic lesions in hypercholesterolemic mice. Thirty male, apoE knockout (apoE-/-) mice were randomly assigned to the following equivalent groups: 1) CO-control: High-fat diet (HFD) administration for 12 weeks. 2) EX-exercise: HFD administration as in CO, and during the last 4 weeks (9th -12th week) ET on treadmill (5sessions/week, 60min/session). At the end of study, blood samples were obtained and all mice were sacrificed. Aortic roots were excised and analysed regarding the percentage of aortic stenosis, and the relative concentrations of collagen, elastin, VE-cadherin, MMP-8,-9 and TIMP-1,-2 within the atherosclerotic lesions. Aortic stenosis was significantly lower in the EX than the CO group (39.63 ± 7.22% vs 62.04 ± 8.55%; p < 0.001), along with considerable increase in fibrous cap thickness and of collagen and elastin contents within plaques (p < 0.05). Compared to controls, exercised-treated mice showed reduced intra-plaque relative concentrations of VE-cadherin (15.09 ± 1.89% vs 23.49 ± 3.01%, p < 0.001), MMP-8 (8.51 ± 2.24% vs 18.51 ± 4.08%, p < 0.001) and MMP-9 (12.1 ± 4.86% vs 18.88 ± 6.23%, p < 0.001). Inversely, the relative concentrations of TIMP-1 and TIMP-2 in the ET group were considerably higher by 62.5% and 31.2% than in the EX group (p < 0.05), respectively. Finally, body weight and lipids concentrations did not differ between groups at the end of the study (p > 0.05). ET treatment induced regression of established atherosclerotic lesions in apoE-/- mice and improved their stability. Those effects seemed to be mediated by favourable modification of VE-cadherin, MMPs and TIMPs.

Association of serum levels of osteopontin and osteoprotegerin with adverse outcomes after endovascular revascularisation in peripheral artery disease.

BACKGROUND: Osteoprotegerin (OPG) and osteopontin (OPN) are vascular calcification inhibitors with a known role in the atherosclerotic and inflammatory process. We investigated their relationship with adverse outcomes (restenosis/adverse cardiovascular events) after endovascular revascularisation of patients with peripheral arterial disease (PAD). METHODS: 203 consecutive patients were enrolled in the PAD group (PADG) and 78 age and sex-matched subjects with less than two cardiovascular risk factors served as control group (COG). PADG underwent standard medical assessment at baseline and 12 months after the procedure. During follow up major adverse cardiovascular events (MACEs) including arterial restenosis with need for reintervention were documented and the PADG was divided accordingly into two subgroups. RESULTS: During 12-month follow-up, 82 MACE were recorded (MACE subgroup). The rest of 124 PAD patients remained free of MACE (non-MACE subgroup). At baseline, OPG (9.89 ± 2.85 ng/ml vs 3.47 ± 1.95 ng/ml, p < 0.001) and OPN (79.99 ± 38.29 ng/ml vs 35.21 ± 14.84 ng/ml, p < 0.001) levels were significantly higher in PADG compared to COG, as well as in MACE subgroup compared to non-MACE subgroup (13.29 ± 3.23 ng/ml vs 10.86 ± 3 ng/ml and 96.45 ± 40.12 ng/ml vs 78.1 ± 38.29 ng/ml, respectively). An independent association of PAD with OPG and OPN was found in the whole patient cohort. Although OPG and OPN were significantly related to MACE incidence in the univariate analysis, multiple logistic regression analysis failed to detect any independent predictor of MACE within the PADG. CONCLUSION: Baseline high OPG and OPN levels were independently associated with PAD presence. Even higher levels of those biomarkers were detected among PAD patients with MACE, however, their prognostic role should be further clarified.

Losartan Interactions with 2-Hydroxypropyl-ß-CD.

Losartan potassium salt (LSR) is a well-known antihypertensive drug with proven beneficial effects on human health. Its formulation with the non-toxic 2-hydroxypropyl-ß-cyclodextrin (2-HP-ß-CD) could improve its pharmacological profile. Thus, its molecular interactions are studied using a combination of Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance (NMR) and Molecular Dynamics (MD). First, its complexation is shown through Differential Scanning Calorimetry as lyophilization provided distinct thermal properties in comparison to the mixture. The complexation is further proved by utilizing the chemical shift changes in the complexation and T1 values. Furthermore, the reversible favorable complexation was shown by MD calculations. Such physical chemical properties provide evidence that this formulation must be further explored through biological experiments.

Comparative Interaction Studies of Quercetin with 2-Hydroxyl-propyl-ß-cyclodextrin and 2,6-Methylated-ß-cyclodextrin.

Quercetin (QUE) is a well-known natural product that can exert beneficial properties on human health. However, due to its low solubility its bioavailability is limited. In the present study, we examine whether its formulation with two cyclodextrins (CDs) may enhance its pharmacological profile. Comparative interaction studies of quercetin with 2-hydroxyl-propyl-ß-cyclodextrin (2HP-ß-CD) and 2,6-methylated cyclodextrin (2,6Me-ß-CD) were performed using NMR spectroscopy, DFT calculations, and in silico molecular dynamics (MD) simulations. Using T1 relaxation experiments and 2D DOSY it was illustrated that both cyclodextrin vehicles can host quercetin. Quantum mechanical calculations showed the formation of hydrogen bonds between QUE with 2HP-ß-CD and 2,6Μe-ß-CD. Six hydrogen bonds are formed ranging between 2 to 2.8 Å with 2HP-ß-CD and four hydrogen bonds within 2.8 Å with 2,6Μe-ß-CD. Calculations of absolute binding free energies show that quercetin binds favorably to both 2,6Me-ß-CD and 2HP-ß-CD. MM/GBSA results show equally favorable binding of quercetin in the two CDs. Fluorescence spectroscopy shows moderate binding of quercetin in 2HP-ß-CD (520 M-1) and 2,6Me-ß-CD (770 M-1). Thus, we propose that both formulations (2HP-ß-CD:quercetin, 2,6Me-ß-CD:quercetin) could be further explored and exploited as small molecule carriers in biological studies.

Design of a Personalized Nasal Device (Matrix-Piston Nasal Device, MPD) for Drug Delivery: a 3D-Printing Application.

The purpose of the current study is the development and the in vitro evaluation of a novel device for the nasal delivery of biodegradable polymeric films. The Matrix-Piston nasal Device (MPD) was designed and then printed employing Fused Deposition Modeling. Particularly, the CAD model of MPD was produced considering the human anatomical features of the nasal cavity and aiming to deliver the formulation on the olfactory region. The device consists of two independent parts constructed by different materials. For the 3D-printing process, different materials were tested to decide the most applicable for each part. More precisely, Thermoplastic Polyurethene (TPU) polymer was selected to print the matrix, while Acrylonitrile Butadiene Styrene (ABS) for the piston. Furthermore, two nasal casts were printed to be used for the assessment of the device. Namely, an hydroxypropyl-methyl cellulose-based drug-free film, containing polyethylene glycol 400 as plasticizer and methyl-ß-cyclodextrin as permeation enhancer, was formed on the MPD to be tested for its ability to be detached from the device and positioned on the artificial olfactory region of the nasal cast. The deposition of the film on the targeted area of the semi-realistic nasal cast took place successfully.

Effects of the Antioxidant Quercetin in an Experimental Model of Ulcerative Colitis in Mice.

Background and Objectives: Quercetin, a member of the flavanol family found in many fruits, vegetables, leaves and grains has been found to have a wide range of biological effects on human physiology. The aim of this study was to investigate the effects of quercetin, when administered orally in the form of the water-soluble inclusion complex with hydroxypropyl-b-cyclodextrin (Que-HP-ß-CD), in an experimental model of ulcerative colitis in mice. Materials and Methods: Animals received either Dextran Sodium Sulphate (DSS), to induce colitis, + Que-HP-ß-CD (Group A), DSS alone (Group B) or no intervention (control, Group C) for 7 days. All animals were weighed daily, and evaluation of colitis was performed using the Disease Activity Index (DAI). On day 7 a blood sample was taken from all animals, they were then euthanised, the large intestine was measured, and histological and immunochemical analyses were performed. Results: The DAI demonstrated an increase over time for the groups receiving DSS (Groups A and B) compared with the control group (Group C), with a significant degree of protection being observed in the group that also received quercetin (Group A): The DAI over time slope for Group B was higher than that for Group A by 0.26 points/day (95% Cl 0.20−0.33, p < 0.01). Weight calculations and immunohistochemistry results validated the DAI findings. Conclusions: In conclusion, the administration of quercetin in an ulcerative colitis model in mice presents a therapeutic/prophylactic potential that warrants further investigation.

Omentin-1 and vaspin serum levels in patients with pre-clinical carotid atherosclerosis and the effect of statin therapy on them.

BACKGROUND: Omentin-1 and vaspin are novel adipokines, and their association with atherosclerosis is still under investigation. The present study aimed to assess the relationship of those adipokines with preclinical, non-significant carotid atherosclerosis and the impact of statin therapy on their levels, suggesting a link between adiposity and atherosclerosis. METHODS: Eighty-four statin-free subjects with non-significant, preclinical carotid atherosclerosis and elevated LDL- cholesterol levels (>130 mg/dl) were recruited to receive atorvastatin (from 10 to 80 mg per day) (atorvastatin group - AG group). Forty-six age- and gender-matched healthy individuals, without any chronic disease served as controls (control group - CG). Clinical parameters, metabolic profile, serum omentin-1, vaspin concentrations and ultrasound measurements of carotid thickening were obtained at the beginning and after 12 months. RESULTS: At baseline, AG showed lower omentin-1 and vaspin serum levels than CG (p ≤ 0.001). Along the entire study population at baseline, omentin-1 levels were independently related to LDL-cholesterol, while vaspin levels were independently associated with hsCRP and the presence of carotid atherosclerosis (p < 0.05). Within AG, 12-months atorvastatin treatment significantly increased omentin-1 (from 202.79 ± 91.41 ng/ml to 262.56 ± 101 ng/ml, p < 0.001) and vaspin concentrations (from 1.29 ± 0.51 ng/ml to 1.70 ± 0.5 ng/ml, p = 0.002). In standard multiple regression analysis, the presence of carotid atherosclerosis related to baseline vaspin levels (ß = -0.232, p < 0.001), while the atorvastatin-induced increase of vaspin was independently associated with hsCRP reduction (ß = -0.198, p = 0.045). CONCLUSION: Low omentin-1 and vaspin serum levels associated with preclinical, non-significant carotid atherosclerosis. Notably, atorvastatin administration significantly increased both adipokines, but the underlying mechanisms and the clinical impact of those changes requires further investigation.

Population pharmacokinetics of anidulafungin in ICU patients assessing inter- and intrasubject variability.

AIMS: The population pharmacokinetics (PK) of anidulafungin in critically ill patients hospitalized in intensive care units (ICUs) was explored with the intention of evaluating and optimizing dosing regimens. METHODS: A PK study was conducted in a cohort of 13 patients treated with anidulafungin using intensive sampling during multiple periods per patient and the high-performance liquid chromatography method for drug quantification. A population PK model was developed to describe the concentration-time course of anidulafungin and the inter-individual (IIV) and interoccasion variability (IOV) of the PK parameters. Model-based PK simulations have been performed to estimate the probability of target attainment (PTA), given the pharmacokinetic/pharmacodynamic target of free 24-hour area under the free drug concentration-time curve over minimum inhibitory concentration for several dosing regimens. RESULTS: A two-compartment PK model, with first-order elimination, best described the data with population clearance (CL) and central/peripheral volume of distribution (V1/V2) of 0.778 L/h and 10.2/21.1 L, respectively, and a mean ± s.d. AUC0-24 of 119.97 ± 46.23 mg·h/L. Pronounced IIV and IOV variability was found for CL (38% and 31%) and V1 (47% and 30%), respectively. Sequential Organ Failure Assessment (SOFA) and Body Mass Index (BMI) were found to be covariates on CL and V1, respectively. Low PTA values were calculated for borderline Clinical & Laboratory Standards Institute (CLSI)-susceptible Candida strains. CONCLUSIONS: Although anidulafungin exposure was found comparable to that in healthy volunteers, elevated interindividual and significant interoccasion variability was found in critically ill ICU patients, which resulted in reduced PTA values in these patients.

The cardiovascular-protective properties of saffron and its potential pharmaceutical applications: A critical appraisal of the literature.

Saffron, the dried stigma of Crocus sativus L., is used in traditional medicine for its healing properties and the treatment of various pathological conditions. The present literature review aimed to summarize and evaluate the preclinical and clinical data regarding the protective effects and mechanisms of saffron and its main components (crocin, crocetin, safranal) on cardiovascular risk factors and diseases. Many in vitro and animal studies have been conducted implicating antioxidant, hypolipidemic, anti-diabetic, and antiinflammatory impact of saffron and its constituents. Notably, there is evidence of direct atherosclerosis regression and stabilization in valid atherosclerosis-prone animal models. However, current clinical trials have shown mostly weak effects of saffron and its constituents on cardiovascular risk factors: (a) Modest lowering of fasting blood glucose, without significant reduction of HbA1c in type 2 diabetic patients, (b) moderate/controversial hypolipidemic effects, (c) negligible hypotensive effect, and (d) inconsistent modification of metabolic syndrome parameters. There are important drawbacks in clinical trial design, including the absence of pharmacokinetic/pharmacodynamic tests, the wide variance of doses and cohorts' characteristics, the small number of patients, the short duration. Therefore, large, properly designed, high-quality clinical trials, focusing on specific conditions are required to evaluate the biological/pharmacological activities and firmly establish the clinical efficacy of saffron and its possible therapeutic uses in cardiovascular diseases.

Comparative pharmacokinetics of the three echinocandins in ICU patients.

BACKGROUND: We conducted a prospective study in ICU patients of two tertiary hospitals in order to determine basic pharmacokinetic (PK) parameters, associated variation and target attainment rates for anidulafungin, micafungin and caspofungin. METHODS: Serum samples from patients treated for 7 days with the standard doses of anidulafungin (N = 13), micafungin (N = 14) or caspofungin (N = 7) were analysed by validated chromatographic methods. PK parameters determined with non-compartmental analysis were correlated with demographic, laboratory and disease severity characteristics. The percentages of patients attaining drug exposures described in the summary of product characteristics (SmPC) documents and preclinical PK/PD targets for stasis were estimated. RESULTS: The median (range) AUC24 was 101.46 (54.95-274.15) mg·h/L for anidulafungin, 79.35 (28.00-149.30) mg·h/L for micafungin and 48.46 (19.44-103.69) mg·h/L for caspofungin. The interindividual variability of anidulafungin, micafungin and caspofungin AUC24 was 46%-58%, attributed mainly to variability in volume of distribution (V), clearance (CL) and in both V and CL, respectively. Significant correlations were found between anidulafungin AUC24 and BMI (rs = -0.670, P = 0.012) and liver enzymes (rs = 0.572-0.665, P = 0.013-0.041) and between caspofungin Cmin and transaminase levels (rs = -0.775 to -0.786, P = 0.036-0.041). Less than 50% of our patients attained the corresponding SmPC median AUC24s and none of the patients attained the PK/PD targets for Candida albicans and Candida parapsilosis. CONCLUSIONS: Anidulafungin exposure in ICU patients was comparable with that reported in non-ICU patients and in healthy volunteers. Micafungin exposure was comparable to that of other patients but ∼30% lower than that in healthy volunteers, whereas caspofungin exposure was rather low (∼50% lower than in healthy volunteers). Larger interindividual variability (50%-60%) was recorded in ICU patients compared with other groups for all three echinocandins.

Preparation and Biophysical Characterization of Quercetin Inclusion Complexes with ß-Cyclodextrin Derivatives to be Formulated as Possible Nose-to-Brain Quercetin Delivery Systems.

Quercetin (Que) is a flavonoid associated with high oxygen radical scavenging activity and potential neuroprotective activity against Alzheimer's disease. Que's oral bioavailability is limited by its low water solubility and extended peripheral metabolism; thus, nasal administration may be a promising alternative to achieve effective Que concentrations in the brain. The formation of Que-2-hydroxypropylated-ß-cyclodextrin (Que/HP-ß-CD) complexes was previously found to increase the molecule's solubility and stability in aqueous media. Que-methyl-ß-cyclodextrin (Que/Me-ß-CD) inclusion complexes were prepared, characterized, and compared with the Que/HP-ß-CD complex using biophysical and computational methods (phase solubility, fluorescence and NMR spectroscopy, differential scanning calorimetry (DSC), and molecular dynamics simulations (MDS)) as candidates for the preparation of nose-to-brain Que's delivery systems. DSC thermograms, NMR, fluorescence spectroscopy, and MDS confirmed the inclusion complex formation of Que with both CDs. Differences between the two preparations were observed regarding their thermodynamic stability and inclusion mode governing the details of molecular interactions. Que's solubility in aqueous media at pH 1.2 and 4.5 was similar and linearly increased with both CD concentrations. At pH 6.8, Que's solubility was higher and positively deviated from linearity in the presence of HP-ß-CD more than with Me-ß-CD, possibly revealing the presence of more than one HP-ß-CD molecule involved in the complex. Overall, water solubility of lyophilized Que/Me-ß-CD and Que/HP-ß-CD products was approximately 7-40 times and 14-50 times as high as for pure Que at pH 1.2-6.8. In addition, the proof of concept experiment on ex vivo permeation across rabbit nasal mucosa revealed measurable and similar Que permeability profiles with both CDs and negligible permeation of pure Que. These results are quite encouraging for further ex vivo and in vivo evaluation toward nasal administration and nose-to-brain delivery of Que.

Hyperhydration using different hydration agents does not affect the haematological markers of the athlete biological passport in euhydrated volunteers.

Athlete Biological Passport (ABP) is an indirect approach, implemented by WADA, aimed at detecting blood manipulation based on abnormal changes in haematological markers. Cases report the use of hyperhydration as masking method during anti-doping urine sample collection which could potentially mask suspicious fluctuations on ABP profiles. This study investigated the hyperhydration effect on haemoglobin concentration, reticulocyte percentage and OFF-hr score (an algorithm based on haemoglobin concentration and reticulocyte percentage), with and without recombinant human erythropoietin (rHuEPO) administration. A five-week clinical study performed; Baseline and rHuEPO Phase. Water and a sports drink were used as hyperhydration agents. To examine the hyperhydration effect on the normal ABP profile per volunteer, hyperhydration was implemented at 0, 24 and 48 hours during the baseline. During the rHuEPO phase, volunteers received Epoetin beta (3000 IU) with hyperhydration to be implemented at 0, 24 and 48 hours after drug administration. Blood and urine samples were collected and analysed according to WADA guidelines. No significant effect on ABP markers was observed due to hyperhydration at any time during the study. Pre- and post-hyperhydration data were not statistically different compared to individual baseline data. In conclusion, hyperhydration does not affect the ABP haematological markers under the examined conditions.

Host-Guest Interactions between Candesartan and Its Prodrug Candesartan Cilexetil in Complex with 2-Hydroxypropyl-ß-cyclodextrin: On the Biological Potency for Angiotensin II Antagonism.

Renin-angiotensin aldosterone system inhibitors are for a long time extensively used for the treatment of cardiovascular and renal diseases. AT1 receptor blockers (ARBs or sartans) act as antihypertensive drugs by blocking the octapeptide hormone Angiotensin II to stimulate AT1 receptors. The antihypertensive drug candesartan (CAN) is the active metabolite of candesartan cilexetil (Atacand, CC). Complexes of candesartan and candesartan cilexetil with 2-hydroxylpropyl-ß-cyclodextrin (2-HP-ß-CD) were characterized using high-resolution electrospray ionization mass spectrometry and solid state 13C cross-polarization/magic angle spinning nuclear magnetic resonance (CP/MAS NMR) spectroscopy. The 13C CP/MAS results showed broad peaks especially in the aromatic region, thus confirming the strong interactions between cyclodextrin and drugs. This experimental evidence was in accordance with molecular dynamics simulations and quantum mechanical calculations. The synthesized and characterized complexes were evaluated biologically in vitro. It was shown that as a result of CAN's complexation, CAN exerts higher antagonistic activity than CC. Therefore, a formulation of CC with 2-HP-ß-CD is not indicated, while the formulation with CAN is promising and needs further investigation. This intriguing result is justified by the binding free energy calculations, which predicted efficient CC binding to 2-HP-ß-CD, and thus, the molecule's availability for release and action on the target is diminished. In contrast, CAN binding was not favored, and this may allow easy release for the drug to exert its bioactivity.

Effect of hyperhydration on the pharmacokinetics and detection of orally administered budesonide in doping control analysis.

The aim of the present study was to investigate if hyperhydration could influence the excretion and subsequent detection of budesonide (BDS) and its main metabolites (6ß-hydroxy-budesonide and 16α-hydroxy-prednisolone) during doping control analysis by leading to concentrations below the WADA reporting level (30 ng/mL). The influence of hyperhydration on the plasma and urinary pharmacokinetic (PK) profiles of BDS and metabolites was also examined. Seven healthy physically active non-smoking Caucasian males participated in a 15-day clinical study. BDS was administered orally at a single dose of 9 mg on Days 1, 7, and 13. Hyperhydration was applied in the morning on two consecutive days, that is, 0 and 24 hours after first fluid ingestion. Water and a commercial sports drink were used as hyperhydration agents (20 mL/kg body weight). Results showed no significant difference (P > 0.05, 95% CI) on plasma or urinary PK parameters under hyperhydration conditions for all the analytes. However, significant differences (P < 0.05, 95% CI) due to hyperhydration were observed on the urinary concentrations of BDS and metabolites. To compensate the dilution effect due to hyperhydration, different adjustment methods were applied based on specific gravity, urinary flow rate, and creatinine. All the applied methods were able to adjust the concentration values close to the baseline ones for each analyte; however, specific gravity was the optimum method in terms of effectiveness and practicability. Furthermore, no masking of the detection sensitivity of BDS or its metabolites was observed due to hyperhydration either in plasma or urine samples.

Hyperhydration-Induced Decrease in Urinary Luteinizing Hormone Concentrations of Male Athletes in Doping Control Analysis.

Low urinary luteinizing hormone (LH) values have been discussed as a marker to detect steroid abuse. However, suppressed LH concentrations related to highly diluted urine samples could be a misleading indication of anabolic steroid abuse. One aim of the present study was to examine the effect of hyperhydration on the interpretation of LH findings during doping control analysis and to investigate different possibilities to correct volume-related changes in urinary LH concentrations. Seven healthy, physically active, nonsmoking White males were examined for a 72-hr period, using water and a commercial sports drink as hyperhydration agents (20 ml/kg body weight). Urine samples were collected and analyzed according to the World Anti-Doping Agency's technical documents. Baseline urinary LH concentrations, expressed as the mean ± SD for each individual, were within the acceptable physiological range (7.11 ± 5.42 IU/L). A comparison of the measured LH values for both hyperhydration phases (Phase A: 4.24 ± 5.60 IU/L and Phase B: 4.74 ± 4.72 IU/L) with the baseline ("normal") values showed significant differences (Phase A: p < .001 and Phase B: p < .001), suggesting the clear effect of urine dilution due to hyperhydration. However, an adjustment of urinary LH concentrations by specific gravity based on a reference value of 1.020 seems to adequately correct the hyperhydration-induced decrease on the LH levels.