0000000000319357
AUTHOR
Anna Lisa Scaturro
CNS-targeted valproic-aminoacid conjugate: preliminary studies on pharmacokinetic parameters and antiepileptic activity
Potential transbuccal delivery of l-DOPA methylester prodrug: stability in the environment of the oral cavity and ability to cross the mucosal tissue
Levodopa (l-DOPA) is the most effective pharmacologic agent in Parkinson's disease and remains the "gold standard". Nevertheless, in long-term treatments, dyskinesias and motor complications can emerge. In this work, the combined use of l-DOPA methylester hydrochloride prodrug (LDME) with transbuccal drug delivery was supposed as a good alternative method to optimize the bioavailability of l-DOPA, to maintain constant plasma levels and to decrease the drug unwanted effects. The effects of environmental pH on buccal delivery of LDME were evaluated ex vivo. The increase of pH value from 5.8 to 6.2 implies an improvement of drug permeation. Since the pH increase causes the raising of hydrolyti…
Aminoacidic derivatives as novel CNS-targeted neurotherapeutics
Drug delivery to the CNS is subject to the permeability limitations imposed by the BBB that regulates movements of actives in and out of the brain. During the drug discovery phase a key aspect could be the selection of the compounds properties crucial for brain penetration. Novel CNS-targeted neurotherapeutics should possess the optimal characteristics that allow passive diffusion through the BBB via the transcellular route, or have the structural features necessary to serve as a substrate for one of the endogenous transport systems of the BBB. An attractive and rewarding chemistry-based strategy, employed to increase the CNS transport of poorly penetrating therapeutic agents, is the transi…
A new dopamine amino-acid conjugate: preclinical in vitro studies and evaluation of behavioural effects in rats
It is well established that alterations in the functionality of dopaminergic transmission are associated with neurodegenerative diseases such as Parkinson’s Disease. The purpose of this study was to investigate the activity of a new dopamine amino-acid conjugate: L-phenylalanine-β-(3,4-dihydroxyphenyl) etilamide(DA-Phe) in the central nervous system, by assessing its influence on different behavioural parameters in the rat. Preliminarily, we tested the in vitro stability in plasmatic environment following the disappearance of DA-Phen from human plasma and the concurrent appearance of dopamine. Using rat brain homogenate, we also evaluated the level of DA-Phen cleavage by cerebral enzymes an…
Buccal delivery as a new challenge for treatment of motor fluctuations in Parkinson's Disease
Sintesi, caratterizzazione e nuove strategie formulative per la somministrazione di nuovi derivati dopaminici nella terapia della malattia di Parkinson.
A NEW DOPAMINE-AMINOACID CONJUGATE: SYNTHESIS AND DETERMINATION OF PHYSICO-CHEMICAL PROPERTIES USEFUL TO CROSS THE BBB
Evaluation of the aptitude to cross the BBB of a new dopamine aminoacidic prodrug
One of the most important factors limiting the development of new drugs for the CNS is the ability to cross the BBB which is a barrier that controls the entrance and exit of both endogenous and exogenous compounds. BBB expresses several transport systems that carry actively into the brain important nutrients (e.g. glucose and amino acids) and are able to import or export various xenobiotics including drugs and their metabolites. The content of active in the brain depends on the overall difference between the drug uptake and drug efflux processes [1]. Dopamine (DA) is a crucial neurotransmitter; its striatal depletion is responsible of clinical signs of Parkinson’s disease (PD). Owing to the…
N-Valproyl-L-Phenylalanine as new potential antiepileptic drug: Synthesis, characterization and in vitro studies on stability, toxicity and anticonvulsant efficacy
Valproic acid (VPA) is considered first-line drug in treatment of generalized idiopathic seizures such as absence, generalized tonic-clonic and myoclonic seizures. Among major antiepileptic drugs, VPA is also considered effective in childhood epilepsies and infantile spasms. Due to its broad activity, VPA acts as a mood stabilizer in bipolar disorder and it is useful in migraine prophylaxis. Despite its long-standing usage, severe reactions to VPA, such as liver toxicity and teratogenicity, are reported. To circumvent side effects due to structural characteristics of VPA, we synthesized in good yield a new VPA-aminoacid conjugate, the N-valproyl-L-Phenylalanine, and characterized by FT-IR, …
DESIGN AND CHARACTERIZATION OF MUCOADHESIVE SUBLINGUAL FILMS CONTAINING FUROSEMIDE
Inhibitory effects of N-valproyl-L-tryptophan on high potassium, low calcium and low magnesium-induced CA1 hippocampal epileptiform bursting activity in rat brain slices.
N-valproyl-l-tryptophan (VPA-Tryp), new antiepileptic drug, was tested on CA1 hippocampal epileptiform bursting activity obtained by increasing potassium and lowering calcium and magnesium concentrations in the fluid perfusing rat brain slices. Each slice was treated with a single concentration (0.2, 0.5, 1 or 2 mM) of Valproate (VPA) or VPA-Tryp. Both burst duration and interburst frequency during and after treatment were off-line compared with baseline values. For both parameters, the latency and the length of statistically significant response periods as well as the magnitude of drug-induced responses were calculated. VPA-Tryp evoked fewer and weaker early excitatory effects than VPA on …
Aloin delivery on buccal mucosa: ex vivo studies and design of a new locoregional dosing system
Context: Chemoprevention of potential malignant disorders or cancerous lesions that affect oral mucosae requires extended duration of treatment. Locoregional delivery of natural products could represent a promising strategy for this purpose. Objective: To investigate the aptitude of aloin to permeate through, or accumulate in, the buccal mucosa and to develop a new prolonged oro-mucosal drug delivery system. Materials and Methods: Permeation/accumulation of aloin from Curacao Aloe (containing 50% barbaloin) was evaluated ex vivo, using porcine buccal mucosa as the most useful model to simulate human epithelium. Oro-mucosal matrix tablets were prepared by dispersing aloin (10% w/w) in Eudrag…
Optimization of local delivery of antifungal agents in the oral cavity by a new formulation
In recent years, with the increased use of antibiotics and immunosuppres-sive agents, there was an increased incidence of oral mycosis and Candida albicans is the most common etiologic agent in oropharyngeal candidiasis, especially in patients with HIV. The aim of this work is to develop a new dosage form containing miconazole (MN) to be topically applied on oral mucosa, allowing for a massive penetration of the drug in the tissue. The vehicle for the drug delivery was lipid microparticles incorporated in a hydrophilic gel. The lipospheres were obtained by hot melt encapsulation method using as matrix ingredients a mixtures of esters of fatty acids with higher fatty alcohols, having low mel…