Synthetic and Natural Radioprotective Agents: Recent Status and their Underlying Mechanism of Action.

Various substances possessing radiation scavenging properties, known as radioprotectors, play a crucial role in shielding organisms from the harmful effects of ionizing radiation (IR) by preventing cellular damage caused by free radicals. Initially, synthetic radioprotectors were developed using thiol synthetic compounds. However, among these, only amifostine (WR-2721) underwent clinical testing as a radioprotector. Various composites with different chemical structures other than thiol compounds were also investigated. However, synthetic radioprotectors are known to be associated with severe side effects, which lead to an inclination towards natural substances. Plants and natural products have emerged as promising sources of radioprotectors, renowned for their non-toxic nature across a broad range of doses and their cost-effectiveness. Radioprotectors are employed in diverse pharmaceutical approaches to mitigate the toxicities induced by radiation. The present review encompasses a detailed account of various synthetic and naturally occurring compounds possessing radioprotective properties, and different investigations related to their radioprotective action, ranging from free radicals scavenging to gene therapy, have also been precisely covered. Numerous radioprotectors have different mechanisms of action, and have proven benefits of naturally occurring compounds over chemically synthesized ones.

Amphiphilic, lauric acid-coupled pluronic-based nano-micellar system for efficient glipizide delivery.

Glipizide; an insulin secretagogue belonging to the sulfonylurea class, is a widely used antidiabetic drug for managing type 2 diabetes. However, the need for life-long administration and repeated doses poses challenges in maintaining optimal blood glucose levels. In this regard, orally active sustained-release nano-formulations can be a better alternative to traditional antidiabetic formulations. The present study explored an innovative approach by formulating orally active sustained-release nano-micelles using the amphiphilic lauric acid-conjugated-F127 (LAF127) block copolymer. LAF127 block copolymer was synthesized through esterification and thoroughly characterized before being employed to develop glipizide-loaded nano-micelles (GNM) via the thin-film hydration technique. The optimized formulation exhibited mean particle size of 341.40 ± 3.21 nm and depicted homogeneous particle size distribution with a polydispersity index (PDI) < 0.2. The formulation revealed a surface charge of -17.11 ± 6.23 mV. The in vitro release studies of glipizide from developed formulation depicted a sustained release profile. Drug loaded micelles exhibited a substantial reduction in blood glucose levels in diabetic rats for a duration of up to 24 h. Notably, neither the blank nano-micelles of LAF127 nor the drug loaded micelles manifested any indications of toxicity in healthy rats. This study provides an insight on suitability of synthesized LAF127 block copolymer for development of effective oral drug delivery systems for anti-diabetic activity without any significant adverse effects.

Comparative Evaluation of Postoperative Sensitivity Following Restoration of Class I Lesions with Different Restorative Materials: An In Vivo Study.

AIM AND OBJECTIVE: This study was undertaken to compare postoperative sensitivity in posterior class I restorations using etch-and-rinse and self-etch composite resins, GC Fuji IX, and Cention-N. MATERIALS AND METHODS: The sample size consisted of 160 participants. After clinical and radiographic examination, the participants were randomly assigned to four groups consisting of 40 participants each according to the restorative materials used. Class I cavity was prepared and was restored on each patient and after restoration postoperative sensitivity was evaluated at 24 h, 48 h, and 7 days using the visual analog scale (VAS). The results were tabulated and statistically analyzed using analysis of variance (ANOVA) and post-hoc multiple comparison tests. RESULTS: There were significant differences present between the groups at 24 h, 48 h, and 7 days. We found that the materials causing least postoperative sensitivity are ranked according to superiority as GC Fuji IX > nano-hybrid composite using self-etch adhesive > Cention-N > nano-hybrid composite using etch-and-rinse adhesive. CONCLUSION: Both GC Fuji IX and self-etch adhesive showed less postoperative sensitivity as compared to etch-and-rinse and Cention-N at 24 h. With GC Fuji IX and self-etch adhesive postoperative sensitivity was decreased while Cention-N also showed good results at 48 h and 7 days. Etch-and-rinse adhesive showed maximum postoperative sensitivity as compared to other groups at 24 h, 48 h, and 7 days. CLINICAL SIGNIFICANCE: Teeth restored with resin composites are susceptible to sensitivity. The restorative material used and their handling can influence postoperative sensitivity.

Albumin-Coated Mesoporous Silica Nanoparticles of Docetaxel: Preparation, Characterization, and Pharmacokinetic Evaluation.

The potential of albumin-coated hollow mesoporous silica nanoparticles (A-HMSNs) to optimize the chemotherapeutic efficacy of docetaxel (DTX) was explored. The synthesized A-DTX-HMSNs had a nanometric size range, offered large surface area with numerous pores, and offered high drug entrapment and loading, that is, 79.18% ± 1.4% and 19.11% ± 1.30%, respectively. Fourier transform infrared spectroscopy and differential scanning calorimetry studies confirmed drug loading and the presence of albumin onto the developed systems, and the drug release followed Higuchi profile. A-HMSNs significantly enhanced the pharmacokinetic profile of DTX by eightfold vis-à-vis the pure DTX. The enhanced plasma levels (Cmax, Tmax, area under the curve), prolonged drug release, long circulation time, lower clearance, hemocompatability, and substantially higher drug loading offered by these nanocarriers inherit promise of a safer and efficacious formulation of DTX.

Optimization and Development of Methotrexate- and Resveratrol-Loaded Nanoemulsion Formulation Using Box-Behnken Design for Rheumatoid Arthritis.

Methotrexate (MTX) is the first line of choice for the management of rheumatoid arthritis (RA) and has been reported for its low bioavailability and side effects. Combination therapy has been widely investigated to overcome bioavailability issues and to reduce adverse effects associated with monotherapy. Various phytoconstituents such as resveratrol (RSV) and curcumin have been found to possess potent anti-inflammatory activity via downregulating the signaling of cytokines (interleukin [IL]-1, IL-6, and tumor necrosis factor alpha) and nuclear factor kappa B signaling. The prime objective of this study was to develop transdermal gel containing MTX-RSV loaded nanoemulsions (NEs) to overcome bioavailability issues and adverse effects of RA monotherapy. The NEs optimized by using Box-Behnken Design were incorporated within gel, and an in vitro skin permeation study performed on rat skin by using vertical Franz diffusion cells exhibited controlled drug release up to 48 h. Subsequently, anti-inflammatory and potential anti-arthritic activities of the combination in nanocarrier were assessed in rats and showed 78.76 ± 4.16% inhibition in inflammation and better anti-arthritic effects. Consequently, integration of dual delivery with nanotechnology can hopefully produce successful therapeutic options for rheumatic diseases.

Resveratrol-loaded folate targeted lipoprotein-mimetic nanoparticles with improved cytotoxicity, antioxidant activity and pharmacokinetic profile.

The aim of present study was to develop folate receptor targeted lipoprotein-mimetic nanoparticles of resveratrol (RSV). Lipoprotein-mimicking nanocarrier (RSV-FA-LNPs) comprising of phosphatidyl choline, cholesterol, stearyl amine and folic acid-tagged bovine serum albumin (FA-BSA) were prepared. Folic acid was conjugated to bovine serum albumin by amide bond at a binding rate of 9.46 ± 0.49 folate molecules per bovine serum albumin. The particle size and entrapment efficiency of the developed nanoparticles was found to be 291.37 ± 3.81 nm and 91.96 ± 1.83%, respectively. The in vitro release study depicted that developed nanocarrier prolonged the drug release till 72 h in phosphate buffer saline (pH 7.4). The anticancer potential of RSV in case of RSV-FA-LNPs was found to be substantially improved against MCF-7 cells overexpressing folate receptors compared to non-targeted nanoparticles. The pharmacokinetics studies after intravenous administration in healthy Wistar rats depicted that lipoprotein mimicking nanoparticles presented the longer circulation time (>48 h) compared to free drug which disappeared in few hours (6 h). The in vitro and preclinical findings of the present study demonstrated the applicability of lipoprotein mimicking nanocarriers for the safer and effective delivery of bioactives.

Resveratrol loaded functionalized nanostructured lipid carriers for breast cancer targeting: Systematic development, characterization and pharmacokinetic evaluation.

Resveratrol (RSV) has shown to possess anti-cancer potential in various studies; however, its poor water solubility, extensive first-pass metabolism, and photostability issues have limited its clinical application. Therefore, the aim of the current investigation was to formulate and optimize a nanostructured lipid carriers (NLCs) based parenteral formulation of RSV for its effective delivery to breast cancer cells. NLCs loaded with RSV (RSV-NLCs) were formulated by the modified solvent injection technique and were systematically optimized using a three level-three factor Box-Behnken design. The optimized RSV-NLCs exhibited an optimum particle size of 88.3 ±â€¯3.1 nm and high entrapment efficiency of 88.0 ±â€¯2.6%. These optimized NLCs were further investigated for the targeting potential using folic acid as the targeting moiety and cell cytotoxicity experiments revealed high cytotoxic effects of folate modified NLCs (RSV-FA-NLCs) compared to unmodified NLCs on MCF-7 cells with high levels of over-expressed folate receptors suggesting the high potential of targeted NLCs in enhancing the therapeutic concentration of RSV to breast cancer cells. In vivo pharmacokinetic studies demonstrated a nine-fold increase in AUC values obtained with RSV-FA-NLCs (57.92 ±â€¯4.15 µg h/mLh) in comparison to free RSV (6.37 ±â€¯1.16 µg h/mLh). The promising results from this investigation corroborated the tremendous potential of lipidic nanocarriers in augmenting the therapeutic potential of RSV.

Mesoporous silica nanoparticles: a smart nanosystem for management of breast cancer.

Breast cancer is the second-leading cause of death in women worldwide owing to aggressive metastasis, lack of early diagnosis and poor access to treatment amenities. During the past decade, mesoporous silica nanoparticles (MSNs) have gained ground for the delivery of a wide variety of chemotherapeutic and bioimaging agents owing to their unique characteristics and straightforward fabrication methods. Present research studies based on MSNs have provided various potential insights in their applicability in breast cancer treatment by improving solubility and stability and decreasing the adverse effects of current treatment regimens. This review focuses on the applicability of this novel modality in the management of breast cancer.

Nanostructured lipid carriers: versatile oral delivery vehicle.

Oral delivery is the most accepted and economical route for drug administration and leads to substantial reduction in dosing frequency. However, this route still remains a challenge for the pharmaceutical industry due to poorly soluble and permeable drugs leading to poor oral bioavailability. Incorporating bioactives into nanostructured lipid carriers (NLCs) has helped in boosting their therapeutic functionality and prolonged release from these carrier systems thus providing improved pharmacokinetic parameters. The present review provides an overview of noteworthy studies reporting impending benefits of NLCs in oral delivery and highlights recent advancements for developing engineered NLCs either by conjugating polymers over their surface or modifying their charge to overcome the mucosal barrier of GI tract for active transport across intestinal membrane.

Dendrimers in drug delivery and targeting: Drug-dendrimer interactions and toxicity issues.

Dendrimers are the emerging polymeric architectures that are known for their defined structures, versatility in drug delivery and high functionality whose properties resemble with biomolecules. These nanostructured macromolecules have shown their potential abilities in entrapping and/or conjugating the high molecular weight hydrophilic/hydrophobic entities by host-guest interactions and covalent bonding (prodrug approach) respectively. Moreover, high ratio of surface groups to molecular volume has made them a promising synthetic vector for gene delivery. Owing to these properties dendrimers have fascinated the researchers in the development of new drug carriers and they have been implicated in many therapeutic and biomedical applications. Despite of their extensive applications, their use in biological systems is limited due to toxicity issues associated with them. Considering this, the present review has focused on the different strategies of their synthesis, drug delivery and targeting, gene delivery and other biomedical applications, interactions involved in formation of drug-dendrimer complex along with characterization techniques employed for their evaluation, toxicity problems and associated approaches to alleviate their inherent toxicity.