Also there are many investigations ongoing with tissue transplantation of fetal and autologous dopamine containing adrenal medulla and glial cell line neurotrophic releasing factor (GDNF) into the cerebral ventricles or basal ganglia or recently TGF-beta assay inducing copies of genes into the brain to enhance the production of dopamine. Although this research showed promise for the treatment and cure, new approach is needed to test the efficacy and safety. The anticholinergic drugs such as biperiden, procycline, orphenadrine, benzhexol, and benztropine are used to improve the tremor and stiffness to a greater degree than akinesia and are overall Inhibitors,research,lifescience,medical mildly
effective [58]. For this reason, nowadays development of new drugs is increasing and improving pharmacological and pharmacokinetic properties compared with L-DOPA [59]. Practical strategies are, therefore, required to develop a system that can facilitate
the transport of new drugs across the BBB for effective management of Parkinsonism. Liposome Inhibitors,research,lifescience,medical formulation was developed during the last years as sustained release systems for drugs to the brain, providing more Inhibitors,research,lifescience,medical effective transport and increasing L-DOPA concentration in the nigrostriatal system after its chemical and enzymatic degradation [60]. Over 30 years ago, it was developed and characterized a new system with dopamine-containing liposomes which exhibited in vitro sustained release of dopamine. These liposomes were stereotactically implanted into the striatum of rats subjected to unilateral lesions of the substantia nigra. This study suggested that dopamine-containing liposomes can partially ameliorate the deficits associated with a rodent model of Parkinson’s disease and demonstrate Inhibitors,research,lifescience,medical the potential of this technology Inhibitors,research,lifescience,medical as a method for the controlled delivery of therapeutic agents into discrete areas of the brain [54]. In 2002 an interesting patent was presented with a method of liposomes
containing the pharmacological compound coupled to an antibody-binding fragment which link to a receptor molecule present on vascular endothelial cells of the BBB. This antibody fragment allows to bring and fix the liposome to the wall of Rolziracetam the endothelial cells of the BBB and to release the drug just in the receptors of the BBB, allowing the entry of the drug only in the brain. The antibody fragment also has to lack a portion or the entire Fc region of the molecule to minimize clearance of the composition by reticuloendothelial system. The receptors used in this patent were transferrin receptor, insulin receptor, insulin-like growth factor (IGF)-I receptor or IGF-II receptor [61], or glucose transport receptor [62]. Another invention based on the same discovery was presented in 2007; this invention used the liposomes but increasing the mean residence time of a camptothecin compound in the brain tissue and extending the benefit of the drug into the brain [63].