Current Drug Delivery - Volume 18, Issue 10, 2021

The use of PLGA in the pharmaceutical industry has only increased as we move towards more and more advanced delivery carrier systems. The qualities of PLGA like biocompatibility, biodegradability and a tunable degradation and drug release has only helped in keeping up the release requirements desired for various delivery platforms. Fine-tuning the release and degradation rate is gaining more and more attention as researchers keep pushing the boundaries of novel delivery carriers. Various experiments are being performed to understand the degradation behavior of PLGA under various physiological and process-related conditions. The understanding of these parameters has helped formulate various ways in which one can fine-tune the properties that can lead to the release of active ingredients encapsulated within. Various techniques have been tried and tested including changes like chemical modification, physical blending and surface modifications and have found to be effective means of release modulation in delivery systems like parenteral, orals, topicals and tissue engineering scaffolds. In this review, all these experiments and implications thereon have been discussed in detail.

Cancer is a global multifactorial disease consisting of over 200 types of cancers. It is well recognized that primary prevention is an effective way to fight cancers by using natural polyphenolic anticancer foods, vegetables, and fruits, avoiding exposure to the carcinogenic environment, smoking cessation, and through lifestyle modifications. The present review provides up-todate information on the effects and functions of pomegranate juice and its bioactive components on the most widespread six cancer types. Pomegranate contains important polyphenolic compounds, such as ellagitannins and punicalagin, with strong antioxidant ability for scavenging free radicals and producing metal-chelates in the biological tissues. The in vitro and in vivo studies suggests that antioxidant and anti-inflammation properties of pomegranate constitute have major antimutagenic and antiproliferative activities for regulating gene expression, modulating cellular mechanisms, and limiting the ability of cancers to metastasize. A limited number of clinical studies have suggested that pomegranate ingredients have the potential for the prevention and treatment of cancer, especially colorectal and prostate cancer. In cancer therapy, it remains a clinical dilemma to hit the right target without inducing side effects. The costly anticancer chemotherapies are often associated with drug resistance and serious side effects in vital organs and noncancerous neighboring cells. It appears that the pomegranate-based phytotherapy would be affordable and cost-effective for next-generation non-pharmacologic anticancer remedies with lesser side effects. However, well-designed, randomized, double-blind, and multi-center studies are needed to establish the long-term safety, efficacy, and dose schedules for orally deliverable pomegranate formulations.

Wound healing is a biological phenomenon of the body involving sequential biochemical processes that are primarily involved in restoring the cellular integrity of the organ. The market related to wound-care products has extensively been expanded and crossed over fifteen billion US dollars, along with twelve billion US dollars for treating wound scars. Different bioactive compounds have shown their various pharmacological actions including wound healing activity. Natural bioactive agents have gained much attention in wound management due to their beneficial nature of possessing least side effects. Some of the bioactive compounds which have shown pronounced wound healing potentials,such as curcumin, quercetin, lawsone, resveratrol, aloe vera, astragaloside, essential oils, growth factors, andrographolide, bilirubin, etc. Most of the natural bioactive agents have limited applicability in clinical practices due to poor aqueous solubility, fast degradation rate and low bioavailability. These problems have been overcome in last few years by encapsulating them into nano-formulations. The nanomaterials of bioactive agents offer discrete advantages like high surface area to volume ratio and nanoscale size offering alternations in physical and chemical properties. These nanomaterials also have sustained controlled release delivery, which seems to be very effective for the lengthy process of wound healing. Many investigations by the global researchers have focused on the emergence of nanomaterials in wound healing applications. In the present review, different natural bioactive agents in the form of nanoformulations have been discussed for wound healing potentials.

Nanomaterials have applications in almost every field and among them, green nanomaterials have various biological applications. Green nanomaterials are specifically useful for drug and DNA delivery applications. Considering that cellulose is the most abundant and easily available biomolecule, it has been used for preparing greener cellulose nanomaterials. Cellulosic nanowhiskers are a cost-effective and green alternative to chemical non-viral gene delivery systems. Cellulose nanowhiskers are commonly extracted from plant sources, and they are generally prepared by sulfuric and hydrochloric acid hydrolysis of plant cellulose. In this review, the topic of cellulose nanowhiskers as green biocompatible materials for gene and drug delivery is discussed with several practical examples.

Background: Having various limitations in conventional drug delivery system, it is important to focus on the target-specific drug delivery system where we can deliver the drug without any degradation. Among various challenges that are thrown to a formulation scientist, delivering the drug to its right site, in its right dose, is also an important aim. A focused drug transport aims to extend, localize, target and have a safe drug interaction with the diseased tissue. Objective: The aim of targeted drug delivery is to make the required amount of the drug available at its desired site of action. Drug targeting can be accomplished in a number of ways that include enzyme mediation, pH-dependent release, use of special vehicles, receptor targeting, among other mechanisms. Intelligently designed targeted drug delivery systems also offer the advantages of a low dose of the drug along with reduced side effects which ultimately improves patient compliance. Incidences of dose dumping and dosage form failure are negligible. A focused drug transport aims to have a safe drug interaction with the diseased tissue. Conclusion: This review focuses on the available targeting techniques from experiment to perfection for delivery to the colon, brain, and other sites of interest. Overall, the article should make an excellent read for the researchers in this area. Newer drug targets may be identified and exploited for successful drug targeting.

Artificial intelligence is an emerging sector in almost all fields. It is not confined only to a particular category and can be used in various fields like research, technology, and health. AI mainly concentrates on how computers analyze data and mimic the human thought process. As drug development involves high R & D costs and uncertainty in time consumption, artificial intelligence can serve as one of the promising solutions to overcome all these demerits. Due to the availability of enormous data, there are chances of missing out on some crucial details. To solve these issues, algorithms like machine learning, deep learning, and other expert systems are being used. On successful implementation of AI in the pharmaceutical field, the delays in drug development, failure at the clinical and marketing level can be reduced. This review comprises information regarding the development of AI, its subfields, its overall implementation, and its application in the pharmaceutical sector and provides insights on challenges and limitations concerning AI.

Cyclodextrin based nanosponges are the designed nanocarriers for the projected delivery of complex drugs. They are multifunctional hypercrosslinked cyclodextrin polymers connected in a three-dimensional, mesh-like network. Their functional characteristics can be fabricated by using different crosslinkers or their different rations with polymer. They can encapsulate various hydrophilic, lipophilic, small-sized or large-sized drug molecules. They offer formulation flexibility and are primarily used for solubility, bioavailability and stability enhancement purposes. This system is also pliable for co-delivery of pharmaceutical entities, improving therapeutic efficacy and patient compliance. If the surface of nanosponge is coupled with an appropriate ligand, even a target specific drug delivery can be achieved. It has a variety of applications in the field of pharmacy for the delivery of tricky drug molecules, proteins, enzymes, natural moieties and gaseous compounds. The list of its applications further widens with the development of nanodiagnostics, nanosensors, biomimetics and scaffolds based on nanosponges. The sudden explosion of research in this working area signifies cyclodextrin nanosponge based products in the market soon.

Background: As per the World Health Organization survey, it has been found that dermatophyte infections are affecting around one-fourth of the world’s population. The dermatophytes are commonly keratinophilic in nature which can multiply and invade the keratinized tissues and affect various parts of the human body like nails, skin, and hair. The luliconazole is an antifungal drug utilized against dermatophytes which causes athlete's foot and ringworm etc. fungal infections of the skin or nails caused by Candida albicans (C.P. Robin) Berkhout and Trichophyton mentagrophytes (Robin) Blanchard. Objective: The study aimed to develop the luliconazole topical cream with turmeric oil and penetration enhancer to improve permeability and enhance antifungal activity. Methods: To prepare the luliconazole topical cream, various compositions of formulation were melted and mixed with varying concentrations of turmeric oil. The oil, drug, and aqueous phases were prepared separately and mixed stepwise in a vessel under continuous stirring at control conditions. Results: The optimized LC2 cream showed pH 6.45±0.12, which is considered suitable to avoid irritation upon topical application. The LC2 cream formulation also showed significantly (p<0.05) more permeability with a permeation flux (0.347 mg/cm2/h) against an aqueous suspension of the drug (0.215 mg/cm2/h). The LC2 cream followed the Higuchi model and showed the drug release from cream via a diffusion mechanism with super case II transport mechanism. Furthermore, the antifungal activity of optimized cream was found better than marketed cream. Conclusion: It is concluded that the prepared luliconazole cream can be an effective anti-fungal treatment with enhanced drug delivery into the skin to treat athlete's foot and ringworm etc. caused by dermatophytes namely C. albicans and Trichophyton spp.

Aim: Folate-conjugated Pluronic F87-poly(lactic-co-glycolic acid) block copolymer (FA-F87-PLGA) was synthesized to encapsulate anticancer drug Paclitaxel (PTX) for targeted drug delivery. To further improve the curative effect, D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS or Vitamin E TPGS) was added to form FA-F87-PLGA/TPGS mixed NPs. Methods: FA-F87-PLGA was synthesized by the ring-opening polymerization, and the structure was characterized. PTX-loaded nanoparticles were prepared with the nanoprecipitation method. The physicochemical characteristics were studied to determine the appropriate dose ratio of the FA-F87-PLGA to TPGS. The cytotoxicity against Ovarian Cancer Cells (OVCAR-3) was determined by MTT assay. The Area Under the Curve (AUC) and half-life were measured in the in vivo pharmacokinetic studies. Results: Based on the optimization of particle size and embedding rate of PTX-loaded mixed NPs, the appropriate dosage ratio of FA-F87-PLGA to TPGS was finally determined to be 5:3. According to in vitro release studies, the cumulative release rate of PTX-loaded FA-F87-PLGA/TPGS mixed NPs was 92.04%, which was higher than that of nanoparticles without TPGS. The cytotoxicity studies showed that the IC50 value of PTX-loaded FA-F87-PLGA/TPGS decreased by 75.4 times and 19.7 times after 72 h treatment compared with free PTX injections and PTX-loaded FA-F87- PLGA NPs, respectively. In vivo pharmacokinetic studies indicated that FA-F87-PLGA/TPGS mixed NPs had a longer drug metabolism time and a larger Area Under the Curve (AUC) compared with free PTX injections. Conclusion: FA-F87-PLGA/TPGS mixed NPs are potential candidates for targeted drug delivery systems.

Introduction: Olmesartan Medoxomil (OM) is an angiotensin receptor blocker and has the adverse effect of celiac like enteropathy which was accepted by the FDA in 2013. This disease is characterized by severe diarrhea, weight loss and enteropathy. Although there are many case reports associated with olmesartan-related enteropathy in humans, it has not been described in a long-term animal model study so far. Aim: We developed a self-microemulsifying drug delivery system (OM-SMEDDS) in our previous study to reduce this side effect of the drug and to enhance bioavailability. Methods: In this study, an artificial hypertension model was established with a dose of 185 μmol /kg L-NAME (N ω-nitro-L-arginine methyl ester) twice in a day intraperitoneally in Wistar albino rats. To determine and compare side effects, the OM-Suspension and OM-SMEDDS were administered at 1.3 mg/kg therapeutic dose during one-month period to the rats. Results: Tension of rats was recorded by measuring from their tails with non invasive blood pressure system. We observed celiac like enteropathy findings like villous atrophy and intraepithelial lymphocytosis and clinical changes like weight loss and severe diarrhea after the treatment with OM-Suspension during one-month experiment. It was also observed that the antihypertensive efficacy of the OM-SMEDDS formulation was higher than the suspension during the experiment, which did not cause enteropathy, diarrhea and weight loss by reducing intestinal exposure. Conclusion: Hereby, we evaluated the side effects of two different pharmaceutical forms by designing a sustainable and reproducible celiac rat model that can be induced with olmesartan medoxomil.

Background: The continuing inflammatory response entailed by atherosclerosis is categorised by a pathological surface expression of certain proteins over the endothelium, namely, P-selectins. Thus, to boost the efficiency of drug carriers, these proteins can be used as binding targets. Objectives: Delivery of particles in a specific size range, from 200 to 3200 nm, covered by P-selectin aptamers (PSA), to an atherosclerotic plaque in a pathologically high haematocrit (Hct) blood flow was simulated. The surface of the plaque was assumed to possess a pathologically high expression of P-Selectins. Methods: An in-silico patient-specific model of a Left Anterior Descending (LAD) coronary artery considering the luminal unevenness was built and meshed using the finite element method. Results: The distribution of deposited particles over the plaque in high Hct blood was significantly more homogenous compared to that of particles that travelled in normal blood Hct. Moreover, in the high Hct, the increase in the particle size, from 800 nm forwards, had a trivial effect on the upsurge in the surface density of adhered particles (SDAs) over the targeted endothelium. Yet, in normal blood Hct (45% in this research), the increase in the particle diameter from 800 nm forwards resulted in a significant increase in the SDAs over the targeted plaque. Interestingly, unlike the adsorption pattern of particles in normal Hct, a significant distribution of deposited particles in the post-constriction region of the atherosclerotic plaque was observed. Conclusion: Our findings provide insights into designing optimum carriers of anti-thrombotic/inflammatory drugs specifically for high blood Hct conditions.

Background: Diclofenac Sodium (DS) injection is widely used in the management of acute or chronic pain and inflammatory diseases. It incorporates 20% w/v Transcutol-P as a solubilizer to make the stable injectable formulation. However, the use of Transcutol-P in high concentration leads to adverse effects such as severe nephrotoxicity, etc. Some advancements have resulted in the formulation of an aqueous-based injectable but that too used benzyl alcohol which is reported to be toxic for human use. Objective: This study aimed to develop an injectable Self-Micro Emulsifying Drug Delivery System (SMEDDS) as a novel carrier of DS for prompt release with better safety and efficacy. Methods: A solubility study was performed with different surfactants and co-surfactants. The conventional stirring method was employed for the formulation of SMEDDS. Detailed in vitro characterization was done for different quality control parameters. In vivo studies were performed using Wistar rats for pharmacokinetic evaluation, toxicological analysis, and analgesic activity. Results: The optimized formulation exhibited good physical stability, ideal globule size (156±0.4 nm), quick release, better therapeutics, and safety, increase in LD50 (221.9 mg/kg) to that of the commercial counterpart (109.9 mg/kg). Furthermore, pre-treatment with optimized formulation reduced the carrageenan-induced rat paw oedema by 88±1.2% after 4 h, compared to 77±1.6% inhibition with commercial DS formulation. Moreover, optimized formulation significantly (p<0.05) inhibited the pain sensation in the acetic-acid induced writhing test in mice compared to its commercial equivalent with a better pharmacokinetic profile. Conclusion: The above findings confirmed that liquid SMEDDS can be a successful carrier for the safe and effective delivery of DS.

Background: Parkinsonism has a toxic cascade of neurodegeneration, with akinesia as a major manifestation. Some antioxidants have shown promise against the disease. Astaxanthin is a powerful antioxidant, demonstrates free radical scavenging, and is also a potential neuroprotective agent. Objective: The objective of this study was to formulate astaxanthin-laden nanostructured lipid carriers based thermoreversible gel for better neuronal uptake and better neuronal efficacy. Methods: The method for fabricating astaxanthin-nanostructured lipid carriers (ATX-NLC) was melt-emulsification, and these were optimized using factorial design and further evaluated for diverse parameters. Neurotoxicity was induced in rats by haloperidol. The treated and non-treated rats were then witnessed for their behaviour. TBARs and GSH levels were also determined. Pharmacokinetics was studied via HPLC. Results: The average particle size (by DLS), entrapment efficiency and zeta potential of optimized ATX-NLC were 225.6 ± 3.04 nm, 65.91 ± 1.22% and -52.64 mV, respectively. Astaxanthin release (after 24 h in simulated nasal fluid) from optimized ATX-NLC was 92.5 ± 5.42%. Its thermoreversible nasal gel (ATX-NLC in-situ gel) was prepared using poloxamer-127. The obtained gel showed in-vivo betterment in the behaviour of animals when studied using the rotarod and akinesia test. Pharmacokinetic studies showed better availability of astaxanthin in the brain on the rats treated with ATX-NLC in-situ gel as compared to those treated with ATX-in-situ gel. Conclusion: Astaxanthin-loaded lipidic nanoparticulate gel can be a hopeful adjuvant therapy for Parkinsonism and holds scope for future studies.

Objective: The objective of this study was to develop and optimize a microflora-triggered colon targeted sustained-release dosage form using Gum Ghatti (GG) and Hydroxypropyl Methylcellulose (HPMC K100). Methods: GG and HPMC K100 were used to prepare microflora triggered colon targeted sustained- release dosage form. For evaluation, two different tablets comprising metoprolol succinate and mesalamine as an active ingredient were used with the objective of developing a platform technology for various categories of drugs. The tablets were coated with Eudragit® L100 and Eudragit® S100 to provide enteric coating and evaluated for hardness, thickness, friability, weight variation, disintegration, and drug content. in vitro release studies for the prepared tablets were carried out mimicking the physiological transit time. Further, the effects of microflora were evaluated using rat cecal content. Results: The in vitro dissolution profile of coated matrix tablets showed that 86.03±0.43% of metoprolol succinate and 80.26±0.67% of mesalamine were released at the end of 12 h. The ex vivo dissolution profile of coated matrix tablets showed that 96.50±0.27% of metoprolol succinate and 92.58±0.39% of mesalamine were released at the end of 12 h in the presence of rat ceacal content. The developed formulation was stable when subjected to the standard ICH stability study conditions. Conclusion: The result of this study showed that gum ghatti together with hydroxypropyl methylcellulose could be successfully used for the preparation of microflora-triggered colon targeted matrix tablets.

Background: Despite significant biological effects, the clinical use of chrysin has been restricted because of its poor oral bioavailability. Objective: The purpose of the present research was to investigate the targeting potential of Mannose decorated chrysin (5,7- dihydroxyflavone) loaded solid lipid nanocarrier (MC-SLNs) for gastric cancer. Methods: The Chrysin loaded SLNs (C-SLNs) were developed, optimized, characterized and further mannosylated. The C-SLNs were developed with a high shear homogenizer, optimized with 32 full factorial designs and characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) and evaluated for particle size/polydispersity index, zeta-potential, entrapment efficiency, % release and haemolytic toxicity. The ex-vivo cytotoxicity study was performed on gastric cancer (ACG) and normal cell lines. Results: DSC and XRD data predict the chrysin encapsulation in the lipid core and FTIR results confirm the mannosylation of C-SLNs. The optimized C-SLNs exhibited a narrow size distribution with a particle size of 285.65 nm. The % Entrapment Efficiency (%EE) and % controlled release were found to be 74.43% and 64.83%. Once C-SLNs were coated with mannose, profound change was observed in a dependent variable - an increase in the particle size of MC-SLNs (307.1 nm) was observed with 62.87% release and 70.8% entrapment efficiency. Further, the in vitro studies depicted MC- SLNs to be least hemolytic than pure chrysin and C-SLNs. MC-SLNs were most cytotoxic and were preferably taken up ACG tumor cells as evaluated against C-SLNs. Conclusion: These data suggested that the MC-SLNs demonstrated better biocompatibility and targeting efficiency to treat gastric cancer.

Background: The clinical application of glabridin in treating skin diseases has been constrained by the limitations of its poor chemical stability and low skin permeability. Objective: Here, we describe Tip-loading Dissolving Microneedles (TDMNs) encapsulating drugs only in the tips of needles for glabridin delivery with improved stability and skin permeability. Methods: The TDMNs fabricated by solvent casting technique had sufficient mechanical strength to penetrate through the excised rat's skin without fracture. Drug delivery efficiency and drug residual in the skin of TDMNs were 63.16% and 49.28%, respectively. Glabridin encapsulated in the tips of TDMNs was effectively delivered into the abdominal skin of rat, and the in vivo delivery efficiency was inversely proportional to the drug doses. Results: Transepidermal Water Loss (TEWL) significantly increased to 34.80 g/m2·h after the application of TDMNs and returned to normal levels (11.31 g/m2·h) after 8 h, indicating that the TDMNs were well tolerated. The stability of glabridin at room temperature was appreciably improved when loaded in TDMNs. Conclusion: These results suggest that intradermal delivery of glabridin by TDMNs is a safe and efficient alternative to currently available routes of administration.

Objective: The outbreak of COVID-19 caused by SARS-CoV-2 has promptly spread worldwide. This study aimed to predict mature miRNA sequences in the SARS-CoV-2 genome, their effects on protein-protein interactions in the affected cells, and gene-drug relationships to detect possible drug candidates. Methods: Viral hairpin structure prediction, classification of hairpins, mutational examination of precursor miRNA candidate sequences, Minimum Free Energy (MFE) and regional entropy analysis, mature miRNA sequences, target gene prediction, gene ontology enrichment, and Protein-Protein Interaction (PPI) analysis, and gene-drug interactions were performed. Results: A total of 62 candidate hairpins were detected by VMir analysis. Three hairpin structures were classified as true precursor miRNAs by miRBoost. Five different mutations were detected in precursor miRNA sequences in 100 SARS-CoV-2 viral genomes. Mutations slightly elevated MFE values and entropy in precursor miRNAs. Gene ontology terms associated with fibrotic pathways and immune system were found to be enriched in PANTHER, KEGG and Wiki pathway analysis. PPI analysis showed a network between 60 genes. CytoHubba analysis showed SMAD1 as a hub gene in the network. The targets of the predicted miRNAs, FAM214A, PPM1E, NUFIP2 and FAT4, were downregulated in SARS-CoV-2 infected A549 cells. Conclusion: miRNAs in the SARS-CoV-2 virus genome may contribute to the emergence of the Covid-19 infection by activating pathways associated with fibrosis in the cells infected by the virus and modulating the innate immune system. The hub protein between these pathways may be the SMAD1, which has an effective role in TGF signal transduction.