0000000000221328
AUTHOR
Ana Catalán-latorre
Protective effect of grape extract phospholipid vesicles against oxidative stress skin damages
Abstract Grape extract rich in polyphenols (∼129 ± 32 mg of gallic acid equivalents per g of dry extract) was obtained from the pomaces of Cannonau grapes by homogenization in an ethanol/water mixture. The efficacy of ultrasounds in speeding up the extraction kinetics of polyphenols was demonstrated. The extract was incorporated in liposomes and PEVs (penetration enhancer containing vesicles) with Labrasol ® or Labrasol ® /ethanol. All the vesicles were spherical and predominantly unilamellar: liposomes were large (∼927 nm) and polydispersed (PI ∼0.56), while PEVs were small (∼140 nm) and fairly homogeneous (PI ∼0.3). Moreover, PEVs were able to incorporate a high amount of the extract (∼98…
Nutriosomes: Prebiotic delivery systems combining phospholipids, a soluble dextrin and curcumin to counteract intestinal oxidative stress and inflammation
Nutriosomes, new phospholipid nanovesicles specifically designed for intestinal protection were developed by simultaneously loading a water-soluble dextrin (Nutriose® FM06) and a natural antioxidant (curcumin). Nutriosomes were easily fabricated in a one-step, organic solvent-free procedure. The stability and delivery performances of the vesicles were improved by adding hydroxypropyl methylcellulose. All the vesicles were small in size (mean diameter ∼168 nm), negatively charged (zeta potential ∼-38 mV, irrespective of their composition), and self-assembled predominantly in unilamellar vesicles stabilized by the presence of Nutriose®, which was located in both the inter-lamellar and inter-v…
Hydroxypropylmethylcellulose films for the ophthalmic delivery of diclofenac sodium
Abstract Objectives The aim of this study was to prepare diclofenac/hydroxypropylmethylcellulose (HPMC) and diclofenac-loaded nanoparticles/HPMC films as potential systems for ocular delivery. Methods Two different concentration of the polymer were used: 1.5 and 2.0% w/v. Chitosan–hyaluronic acid nanoparticles were prepared by the ionotropic gelation technique. Nanoparticles were characterized by transmission electron microscopy, dynamic light scattering, drug encapsulation efficiency and rheological studies. In-vitro drug studies and corneal penetration release studies were carried out. Drug release mechanism was finally evaluated by fitting the Ritger and Peppas equation to data. In addit…
Freeze-dried eudragit-hyaluronan multicompartment liposomes to improve the intestinal bioavailability of curcumin.
This work aimed at finding an innovative vesicle-type formulation able to improve the bioavailability of curcumin upon oral administration. To this purpose, phospholipid, Eudragit® S100 and hyaluronan sodium salt were combined to obtain eudragit-hyaluronan immobilized vesicles using an easy and environmentally-friendly method. For the first time, the two polymers were combined in a system intended for oral delivery, to enhance curcumin stability when facing the harsh environment of the gastrointestinal tract. Four different formulations were prepared, keeping constant the amount of the phospholipid and varying the eudragit-hyaluronan ratio. The freeze-drying of the samples, performed to inc…
In Situ Study of the Effect of Naringin, Talinolol and Protein-Energy Undernutrition on Intestinal Absorption of Saquinavir in Rats
To study the potential interactions of naringin (NAR), talinolol (TAL) and protein-energy undernutrition (PEU) in the absorption process of saquinavir (SQV), perfusion experiments were performed in the small intestine of rats at different SQV concentrations. The results obtained demonstrated that SQV intestinal absorption was described by simultaneous passive diffusion (kdif = 3.44 hr) and saturable absorption (Vma = 127.31 lM ⁄ hr; Kma =1 0.50lM) together with a capacity-limited efflux (Vms = 270.53 lM ⁄ hr; Kms =2 3.44lM). The competitive inhibition constants of NAR on the SQV input and efflux processes were (IC50)a =3 .98l Ma nd(IC50)s = 5.00 lM, respectively. NAR significantly decreased…
Impact of nutritional status on the pharmacokinetics of erlotinib in rats
Malnourishment is a complex condition in which physiopathological changes take place in multiple systems as a result of energy, protein and nutrient deficiency. The purpose of this study was to evaluate, using an experimental animal model, the impact of nutritional status on the pharmacokinetic profile of erlotinib, a reversible, highly selective, human epidermal growth factor receptor (HER1/EGFR) tyrosine kinase inhibitor. Two groups of rats -WN (well-nourished) and UN (undernourished) - were fed with different diets for 23-26 days. Rats were assigned randomly to one of three erlotinib treatments (n = 42) consisting of a single dose administered intravenously (i.v.), via oral solution or v…
A preclinical study to model taurine pharmokinetics in the undernourished rat
AbstractMalnutrition is a common feature of chronic and acute diseases, often associated with a poor prognosis, including worsening of clinical outcome, owing, among other factors, to dysfunction of the most internal organs and systems affecting the absorption, metabolism and elimination of drugs and nutrients. Taurine is involved in numerous biological processes and is required in increased amounts in response to pathological conditions. The aim of this study was to describe the behaviour of taurine in well-nourished (WN) rats and to analyse the influence of protein–energy undernutrition on the pharmacokinetic (PK) parameters of taurine, using a PK model. Wistar rats were randomly distribu…