Carbamazepine and levetiracetam-loaded PLGA nanoparticles prepared by nanoprecipitation method: in vitro and in vivo studies

Apolipoprotein E3 functionalized lipid-drug conjugated nanoparticles of Levetiracetam for enhanced delivery to the brain: In-vitro cell line studies and in-vivo study

A significant portion of brain-tumor patients suffer from 'brain-tumor-related epilepsy (BTE)' which results in depression, anxiety and hampered quality of life. Conventional anti-epileptic drugs indicate negative interaction with other drugs augmenting the poor outcome of overall therapy. Levetiracetam (LVM) has evidenced effectiveness for BTE but its hydrophilicity restricts the passage into blood-brain barrier. The majority of lipid nanoparticles fails to load hydrophilic drug sufficiently. Therefore, lipid-drug conjugates (LDC) were synthesized using stearic acid via amide bond formation confirmed by FTIR and NMR. The nanoparticles of synthesized LDC were prepared by solvent injection method followed by functionalization with Apolipoprotein E3 (ApoE3@LDC-NP). The nanoparticles were characterized by DSC, XRD, particle size (131.6 ± 1.24 nm), zeta potential (-15.6 ± 0.09 mV), and for storage stability. In-vitro release study indicated initial burst release of 20 ± 0.63 % followed by sustained release up to 30 h (66 ± 1.40 %) for ApoE3@LDC-NP. The cell-line study on HEK293 indicated no significant cytotoxic effect and greater cell uptake through U87MG cell line. The pharmacokinetic and bio-distribution study indicated 2.5-fold greater brain-targeting of ApoE3@LDC-NP as compared to LVM solution. It proved safe in the haemolysis study and exhibited the absence of tissue necrosis. Thus, ApoE3@LDC-NP might be a promising approach for effective brain-targeting of LVM for improved clinical response in BTE.

PLGA nanoparticle loaded with antioxidants and photosensitizer for ROS shock mediated phototherapy of triple negative breast cancer

The potential use of antioxidants for photodynamic therapy (PDT) is investigated in this study. PDT causes reactive oxygen species (ROS)-mediated cell death; on the contrary, antioxidants scavenge ROS. The use of a photosensitizer along with an antioxidant photosensitizer compensates for the loss of ROS due to the use of antioxidant, eventually leading to cell death. In this work, for PDT and photothermal therapy (PTT), we have combined the photosensitizer IR 792 perchlorate dye with the antioxidants alpha-tocopherol (A) andp-coumaric acid (C) encapsulated in a polymeric nanocarrier (AC IR NPs). We have reported the synthesis of AC IR NPs using poly lactic-co-glycolic acid (PLGA) by nanoprecipitation method. The size of the polymeric nanoparticles was found to be 80.4 ± 15.6 nm, with a spherical morphology observed by scanning electron microscopy and transmission electron microscopy. The synthesized AC IR NPs demonstrated good biocompatibility in fibroblast cell lines (L929). Furthermore, the efficacy assessment of the as prepared nanosystemin vitroon breast cancer cell lines (4T1) revealed a significant cell death of nearly 80%. This could be attributed to the ROS generation leading to oxidative stress and inhibition of metastasis. This study provides evidence that the combination of antioxidant drugs along with photosensitizers have the potential to be an effective therapy for treating triple negative breast cancer.

Intranasal Polymeric and Lipid-Based Nanocarriers for CNS Drug Delivery

Nanomedicine is currently focused on the design and development of nanocarriers that enhance drug delivery to the brain to address unmet clinical needs for treating neuropsychiatric disorders and neurological diseases. Polymer and lipid-based drug carriers are advantageous for delivery to the central nervous system (CNS) due to their safety profiles, drug-loading capacity, and controlled-release properties. Polymer and lipid-based nanoparticles (NPs) are reported to penetrate the blood–brain barrier (BBB) and have been extensively assessed in in vitro and animal models of glioblastoma, epilepsy, and neurodegenerative disease. Since approval by the Food and Drug Administration (FDA) of intranasal esketamine for treatment of major depressive disorder, intranasal administration has emerged as an attractive route to bypass the BBB for drug delivery to the CNS. NPs can be specifically designed for intranasal administration by tailoring their size and coating with mucoadhesive agents or other moieties that promote transport across the nasal mucosa. In this review, unique characteristics of polymeric and lipid-based nanocarriers desirable for drug delivery to the brain are explored in addition to their potential for drug repurposing for the treatment of CNS disorders. Progress in intranasal drug delivery using polymeric and lipid-based nanostructures for the development of treatments of various neurological diseases are also described.

Fighting Epilepsy with Nanomedicines-Is This the Right Weapon?

Epilepsy is a chronic and complex condition and is one of the most common neurological diseases, affecting about 50 million people worldwide. Pharmacological therapy has been, and is likely to remain, the main treatment approach for this disease. Although a large number of new antiseizure drugs (ASDs) has been introduced into the market in the last few years, many patients suffer from uncontrolled seizures, demanding the development of more effective therapies. Nanomedicines have emerged as a promising approach to deliver drugs to the brain, potentiating their therapeutic index. Moreover, nanomedicine has applied the knowledge of nanoscience, not only in disease treatment but also in prevention and diagnosis. In the current review, the general features and therapeutic management of epilepsy will be addressed, as well as the main barriers to overcome to obtain better antiseizure therapies. Furthermore, the role of nanomedicines as a valuable tool to selectively deliver drugs will be discussed, considering the ability of nanocarriers to deal with the less favourable physical-chemical properties of some ASDs, enhance their brain penetration, reduce the adverse effects, and circumvent the concerning drug resistance.

In Vivo Evaluation of Nanoemulsion Formulations for Metformin and Repaglinide Alone and Combination

Repaglinide and Metformin are used to treat Type 2 diabetes. Repaglinide with poor water solubility has relatively low oral bioavailability (56%) and undergoes hepatic first-pass metabolism. The oral bioavailability of metformin HCl is also low (about 50-60%). The purpose of this study was to prepare nanoemulsion formulations containing metformin HCl or repaglinide alone or in combination and characterize them in vitro and in vivo. Nanoemulsion formulations containing metformin HCl and/or repaglinide were successfully prepared and in vitro characterized. In addition, in vivo efficacy of nanoemulsion formulations was evaluated in a streptozotocin-nicotinamide-induced diabetic rat model. Biochemical, histopathological, and immunohistochemical evaluations were also performed. The mean droplet size and zeta potential values of nanoemulsion formulations were in the range of 110.15±2.64-120.23±2.16 nm and -21.95 - -24.33 mV, respectively. The percent entrapment efficiency values of nanoemulsion formulations were in the range of 93.600%-96.152%. All nanoemulsion formulations had a PDI of ≤0.223. A statistically significant decrease was observed in the blood glucose values of the diabetic rats treated with nanoemulsion formulations containing active substance/substances, compared to diabetic rats (control) (p<0.05). Nanoemulsion formulations (especially nanoemulsion containing metformin HCl and repaglinide combination) have a better antidiabetic activity and are more effective in reducing oxidative stress caused by diabetes.

Repositioning of drugs for Parkinson's disease and pharmaceutical nanotechnology tools for their optimization

Parkinson's disease (PD) significantly affects patients' quality of life and represents a high economic burden for health systems. Given the lack of safe and effective treatments for PD, drug repositioning seeks to offer new medication alternatives, reducing research time and costs compared to the traditional drug development strategy. This review aimed to collect evidence of drugs proposed as candidates to be reused in PD and identify those with the potential to be reformulated into nanocarriers to optimize future repositioning trials. We conducted a detailed search in PubMed, Web of Science, and Scopus from January 2015 at the end of 2021, with the descriptors "Parkinson's disease" and "drug repositioning" or "drug repurposing". We identified 28 drugs as potential candidates, and six of them were found in repositioning clinical trials for PD. However, a limitation of many of these drugs to achieve therapeutic success is their inability to cross the blood-brain barrier (BBB), as is the case with nilotinib, which has shown promising outcomes in clinical trials. We suggest reformulating these drugs in biodegradable nanoparticles (NPs) based on lipids and polymers to perform future trials. As a complementary strategy, we propose functionalizing the NPs surface by adding materials to the surface layer. Among other advantages, functionalization can promote efficient crossing through the BBB and improve the affinity of NPs towards certain brain regions. The main parameters to consider for the design of NPs targeting the central nervous system are highlighted, such as size, PDI, morphology, drug load, and Z potential. Finally, current advances in the use of NPs for Parkinson's disease are cited.

Innovative treatments for epilepsy: Venom peptides, cannabinoids, and neurostimulation

Antiepileptic drugs have been successfully treating epilepsy and providing individuals sustained seizure freedom. However, about 30% of the patients with epilepsy present drug resistance, which means they are not responsive to the pharmacological treatment. Considering this, it becomes extremely relevant to pursue alternative therapeutic approaches, in order to provide appropriate treatment for those patients and also improve their quality of life. In the light of that, this review aims to discuss some innovative options for the treatment of epilepsy, which are currently under investigation, addressing strategies that go from therapeutic compounds to clinical procedures. For instance, peptides derived from animal venoms, such as wasps, spiders, and scorpions, demonstrate to be promising antiepileptic molecules, acting on a variety of targets. Other options are cannabinoids and compounds that modulate the endocannabinoid system, since it is now known that this network is involved in the pathophysiology of epilepsy. Furthermore, neurostimulation is another strategy, being an alternative clinical procedure for drug-resistant patients who are not eligible for palliative surgeries.

Preparation of fluorescent nanoparticles based on broken-rice starch for live-cell imaging

Native broken-rice starch was used to create starch nanoparticles (StNPs) with particle sizes ranging from 100 nm to 800 nm. The fluorescent isothiocyanate poly-l-lysine StNPs (FITC-PLL-StNPs) were created in two steps. First, the StNPs were electrostatically modified by poly-l-lysine (PLL) molecules rich in amino acids. Second, fluorescein isothiocyanate reacted with some amino groups on PLL molecules (FITC). Fluorescence spectrophotometry was used to determine the degree of substitution (DS) and fluorescent properties of fluorescent starches. The study found that FITC-PLL-StNP-200 has higher fluorescence stability, more phagocytic cells, and a better and clearer fluorescence detecting effect than FITC-PLL-St, FITC-PLL-StNP-100, FITC-PLL-StNP-400, and FITC-PLL-StNP-800. The biological evaluation results showed that FITC-PLL-StNP-200 did not affect the viability of HeLa cells at the lysosome labeling concentration. These findings suggest that FITC-PLL-StNP-200 has strong and stable fluorescence, indicating that FITC-PLL-StNP-200 can be used as a fluorescent probe and lysosome marker in a variety of applications, particularly in biomedicine.

Comparative statistical analysis of the release kinetics models for nanoprecipitated drug delivery systems based on poly(lactic-co-glycolic acid)

Poly(lactic-co-glycolic acid) is one of the most used polymers for drug delivery systems (DDSs). It shows excellent biocompatibility, biodegradability, and allows spatio-temporal control of the release of a drug by altering its chemistry. In spite of this, few formulations have reached the market. To characterize and optimize the drug release process, mathematical models offer a good alternative as they allow interpreting and predicting experimental findings, saving time and money. However, there is no general model that describes all types of drug release of polymeric DDSs. This study aims to perform a statistical comparison of several mathematical models commonly used in order to find which of them best describes the drug release profile from PLGA particles synthesized by nanoprecipitation method. For this purpose, 40 datasets extracted from scientific articles published since 2016 were collected. Each set was fitted by the models: order zero to fifth order polynomials, Korsmeyer-Peppas, Weibull and Hyperbolic Tangent Function. Some data sets had few observations that do not allow to apply statistic test, thus bootstrap resampling technique was performed. Statistic evidence showed that Hyperbolic Tangent Function model is the one that best fit most of the data.

Orally disintegrating tablet containing carbamazepine and levetiracetam: formulation and in vitro and in vivo characterization

This study aimed to prepare and characterize the orally disintegrating tablet (ODT) formulations containing the combination of levetiracetam (LEV) and carbamazepine (CBZ) (CBZ + LEV combination) for the treatment of epilepsy. The ODT formulations were prepared using the lyophilization (L) and direct compression (DC) methods. The flowability of the mixed powders used for DC formulation was evaluated. The quality control tests for the ODTs were performed. Also, the antiepileptic effects of pure drugs, their combination, and the suspension of CBZ + LEV-DC-ODT formulation were evaluated in the rats with pentylenetetrazole (PTZ)-induced epilepsy model. The obtained results for the mixed powders of the DC formulation (angle of repose: 26.18 ± 0.794°; compressibility index: 15.24 ± 0.764%) suggest that the flow properties of the powder blend were suitable for the preparation of CBZ + LEV-ODT using DC method. The mean values of diameter and hardness of L-ODTs and DC-ODTs were found to be 16.87 mm and 16.18 mm and 11.96 N and 30.11 N, respectively. The friability of both formulations was <1%. Both formulations were disintegrated in seconds. Drugs in L-ODT had faster dissolution than those in DC-ODT. Compared to the seizure scores obtained for the groups treated with LEV or CBZ, generally, there was a higher decrease in seizure scores in the groups treated with CBZ + LEV combination or the suspension of CBZ + LEV-DC-ODTs. Consequently, the ODT formulations containing the CBZ + LEV combination might be beneficial in the treatment of epilepsy.

Cefaclor Monohydrate-Loaded Colon-Targeted Nanoparticles for Use in COVID-19 Dependent Coinfections and Intestinal Symptoms: Formulation, Characterization, Release Kinetics, and Antimicrobial Activity

Corona virus disease-2019 (COVID-19) emerged in Wuhan, China in December 2019 and was declared as a pandemic by the World Health Organization in March 2020. Although there is no complete treatment protocol for COVID-19, studies on this topic are ongoing, and it is known that broad-spectrum antibiotics such as cephalosporins are used for coinfections and symptoms in COVID-19 patients. Studies have shown that Staphylococcus aureus and Escherichia coli bacteria can cause symptoms such as diarrhea and coinfections accompanying COVID-19. Therefore, in this study, colon-targeted cefaclor monohydrate (CEF)-loaded poly(lactic-co-glycolic acid) (PLGA)-Eudragit S100 nanoparticles (NPs) were prepared using a nanoprecipitation technique. The particle sizes of the CEF-loaded NPs were between 171.4 and 198.8 nm. The encapsulation efficiency was in the range of 58.4%-81.2%. With dissolution studies, it has been concluded that formulations prepared with Eudragit S100 (E-coded) and Eudragit S100+PLGA (EP-coded) are pH-sensitive formulations and they are targetable to the colon, whereas the formulation prepared only with PLGA (P-coded) can release a higher CEF rate in the colon owing to the slow release properties of PLGA. The release kinetics were fitted to the Korsmeyer-Peppas and Weibull models. The antibacterial activity of E-, EP-, and P-coded formulations was 16-fold, 16-fold, and 2-fold higher than CEF, respectively, for S. aureus and E. coli according to the microdilution results. As a result of the time killing experiment, all formulations prepared were found to be more effective than the antibiotic itself for long periods. Consequently, all formulations prepared in this study hope to guide researchers/clinicians in treating both gram-positive and gram-negative bacteria-induced infections, as well as COVID-19 associated coinfections and symptoms.