Review of the Application of Nanovesicles and the Human Interstitial Fluid in Gastrointestinal Premalignant Lesion Detection, Diagnosis, Prognosis and Therapy

The Therapeutic Potential of Novel Carnosine Formulations: Perspectives for Drug Development

Carnosine (beta-alanyl-L-histidine) is an endogenous dipeptide synthesized via the activity of the ATP-dependent enzyme carnosine synthetase 1 and can be found at a very high concentration in tissues with a high metabolic rate, including muscles (up to 20 mM) and brain (up to 5 mM). Because of its well-demonstrated multimodal pharmacodynamic profile, which includes anti-aggregant, antioxidant, and anti-inflammatory activities, as well as its ability to modulate the energy metabolism status in immune cells, this dipeptide has been investigated in numerous experimental models of diseases, including Alzheimer's disease, and at a clinical level. The main limit for the therapeutic use of carnosine is related to its rapid hydrolysis exerted by carnosinases, especially at the plasma level, reason why the development of new strategies, including the chemical modification of carnosine or its vehiculation into innovative drug delivery systems (DDS), aiming at increasing its bioavailability and/or at facilitating the site-specific transport to different tissues, is of utmost importance. In the present review, after a description of carnosine structure, biological activities, administration routes, and metabolism, we focused on different DDS, including vesicular systems and metallic nanoparticles, as well as on possible chemical derivatization strategies related to carnosine. In particular, a basic description of the DDS employed or the derivatization/conjugation applied to obtain carnosine formulations, followed by the possible mechanism of action, is given. To the best of our knowledge, this is the first review that includes all the new formulations of carnosine (DDS and derivatives), allowing a decrease or complete prevention of the hydrolysis of this dipeptide exerted by carnosinases, the simultaneous blood-brain barrier crossing, the maintenance or enhancement of carnosine biological activity, and the site-specific transport to different tissues, which then offers perspectives for the development of new drugs.

Chrysin loaded nanovesicles ameliorated diabetic peripheral neuropathy. Role of NGF/AKT/GSK-3β pathway

Diabetic peripheral neuropathy (DPN) is a common diabetic complication. Chrysin (CHY) has many biological properties but poor oral bioavailability. This study investigates the effect of CHY and CHY-loaded nanovesicles (CHY-NVs) on streptozotocin (STZ)-induced DPN in rats. CHY-NVs were prepared by using film hydration method. The formula with the best entrapment efficiency%, lowest particle size, highest zeta potential, and highest in vitro CHY released profile was selected, characterized by Differential scanning calorimetry, Fourier transformation infrared spectroscopy analysis, and examined by Transmission electron microscope. Acute toxicity test, pharmacokinetic study and experimental model of diabetes mellitus were performed on the selected formulation. Wistar rats were considered diabetic by administration of a single intraperitoneal dose of STZ (50 mg/kg). 48 h after STZ administration, hyperglycemic rats were randomly assigned into four groups, one group of untreated hyperglycemic rats and the other three groups received daily oral doses of unloaded NVs, CHY-NVs (25 mg/kg), and CHY-NVs (50 mg/kg), respectively for 21 days. Moreover, five additional groups of healthy rats received: distilled water (control), free CHY, unloaded NVs, and CHY-NVs respectively for 21 days. CHY and CHY-NVs maintained body weight and reduced STZ-induced behavioral changes in rotarod, hind paw cold allodynia, tail cold allodynia, tail flick, and hot plate tests. CHY and CHY-NVs lowered blood glucose, glycated hemoglobin, elevated serum reduced glutathione (GSH), and reduced plasma malondialdehyde (MDA) levels. CHY-NVs elevated phosphatidylinositol 3-kinase (Pi3k), phosphorylated protein kinase B (p-AKT), and reduced nuclear factor kappa B (NF-κB), interleukin-6 (IL-6) in sciatic nerve homogenate. CHY and CHY-NVs increased nerve growth factor (NGF) and decreased glycogen synthase kinase-3β (GSK-3β) gene expressions in the sciatic nerve. In conclusion, CHY and CHY-NVs ameliorated STZ-induced DPN behavioral and histopathological changes via attenuating hyperglycemia, exerting anti-oxidant, anti-inflammatory effects, activating NGF/p-AKT/GSK-3β pathway, and its anti-apoptotic effect. The best pharmacokinetic profile and therapeutic effect was observed in rats treated with CHY-loaded NVs.

Supramolecular Vesicles Based on Amphiphilic Pillar[n]arenes for Smart Nano-Drug Delivery

Supramolecular vesicles are the most popular smart nano-drug delivery systems (SDDs) because of their unique cavities, which have high loading carrying capacity and controlled-release action in response to specific stimuli. These vesicles are constructed from amphiphilic molecules via host-guest complexation, typically with targeted stimuli-responsive units, which are particularly important in biotechnology and biomedicine applications. Amphiphilic pillar[n]arenes, which are novel and functional macrocyclic host molecules, have been widely used to construct supramolecular vesicles because of their intrinsic rigid and symmetrical structure, electron-rich cavities and excellent properties. In this review, we first explain the synthesis of three types of amphiphilic pillar[n]arenes: neutral, anionic and cationic pillar[n]arenes. Second, we examine supramolecular vesicles composed of amphiphilic pillar[n]arenes recently used for the construction of SDDs. In addition, we describe the prospects for multifunctional amphiphilic pillar[n]arenes, particularly their potential in novel applications.