Current Drug Therapy - Volume 10, Issue 1, 2015

Cyclodextrins (CDs) are capable of including compounds hydrophilic or lipophilic, possessing geometry and polarity well-suited with their cavity. Cyclodextrinbased nanosponges (CD-NS), which are anticipated as a new-fangled nanosized delivery system, are ground-breaking hyper-crosslinked cyclodextrin polymers nanostructured within a three-dimensional network. These colloidal systems possess numerous nanocavities which embrace actives (active substances) and forms inclusion complexes; thereby enhancing solubility of drugs, ensuring sustained release for prolonged time and altering pharmacokinetic parameters to improve their bioavailability. As well, by altering the polymer to crosslinker ratios, desired size and release rate of these nanoporous systems can be achieved. Owing to their tiny size, shape and complexity; CD-NS are not only enormously competent for formulating into a wide range of dosage forms but also proficiently evade physicochemical degradation of actives. Development of nanosponges as drug delivery systems, particularly cyclodextrin based nanosponges is brought up in this review article. Efforts have been made to exemplify the characteristics of cyclodextrin based nanosponges along with their applications in pharmaceutical field and drug delivery. Special importance has been given on discussing the preparation methods, characterization techniques and prominent applications of these novel drug delivery carriers for therapeutic purposes.

Application of biopharmaceutical concepts to formulation development has revolutionized strategy for dosage form design. Nanotechnology has become an essential element of pharmaceutical sciences and finds multiple applications in drug delivery systems in enhancing therapeutic performance of drugs. Many of the current “nano” drug delivery systems are pedigree of conventional dosage forms like nanosuspensions, nanoemulsions, and nanomicelles. Nanosuspension is an approach to deliver water insoluble and poorly bioavailable drugs by reducing size to submicron range. Thereby its dissolution rate is increased and hence the bioavailability, where drug dissolution rate is the limiting factor. Nanoemulsions are O/W or W/O emulsion, having droplet size from 20-200 nm that are transparent and do not have the tendency to coalesce. Nanoemulsions show great aesthetic appeal and skin feel and find their application in transdermal delivery of drugs, topical application for systemic drug delivery, oral delivery of proteins and delivering drugs through parenteral and intranasal routes. Nanomicelles are self-assembling nanosized (usually with particle size within a range of 10 to 100 nm) colloidal dispersions with a hydrophobic core and hydrophilic shell. These are currently used as pharmaceutical carriers for solubilizing hydrophobic drugs and provide drug delivery platform to be exploited for multiple routes of administration. All of these nano formulations combine the advantage of maximizing therapeutic benefits with minimized side effects and improved safety, since they have enormous potential of being targeted at cellular level. This review describes various facets of nano drug delivery systems in relation to formulation, characterization, potential benefits and risks, and pharmaceutical applications in drug delivery.

The main objective of present investigation was to study the influence of Piper betle on the permeation of Naproxen sodium gel when applied on skin. This route avoids the side effects of NSAIDS on oral administration like irritation of the gastrointestinal tract, and systemic toxicity and improves the patient compliance and therapeutic efficacy. The leaves of P. betle were subjected to maceration using successive solvent extraction with solvents like n-hexane, chloroform, methanol and water. All four extracts were screened for preliminary phytochemical tests. The carbopol gel formulations containing Naproxen sodium (1% w/w) and selected concentrations (1% / 2% w/w) of synthetic penetrations enhancers or four herbal extracts were prepared as various batches. These formulations were subjected to characterization tests of colour, pH, viscosity, spreadability. Formulations were subjected to ex-vivo permeation of the drug across rat skin using Franz diffusion cell. The permeation using herbal extracts was compared with synthetic penetration enhancer, Transcutol P(TP). The formulation containing 2% w/w of N- hexane extract (NHE) showed better % cumulative release (47.97%) and flux (157.072 µg/cm2.h), as compared to synthetic enhancer transcutol P (43.11% CR and flux as 141.15 µg/cm2..h) and other extracts. Histopathology shows focal stripping of stratum corneum and normal adnexal structure in both these formulations (containing NHE & TP). But mild degeneration of epidermis and dermis was seen along with hemorrhage in skin treated with formulation containing TP. The results suggest that Piper betle may be safer and better option for increasing the skin permeability of Naproxen sodium as compared to synthetic penetration enhancers.

Clinical cancer treatment and therapy have been gradually improved by experimental and clinical advancements worldwide, especially after the advent of different types of individualized cancer therapy (ICT) and new generations of anticancer drugs. Despite the long history of anticancer drug sensitivity testing (DST), its therapeutic benefits to clinical cancer patients are compromised and controversial. DST techniques are diversified and improved a great deal, but they have not been developed into an overwhelming means to cure all cancer patients in clinics. The retrospection and panorama of historic and evolutionary developments of DST including clinical relevance, advantageous, technical cautions, limitations or even shortcomings of varied models and methodologies at present stage are addressed. Possible future directions and novel ideas are also discussed and highlighted.

An important function of endothelial cells is to maintain a balance between the production of vasodilators such as nitric oxide (NO) and vasoconstrictors such as endothelin-1, thereby maintaining vascular tone and blood flow. However in many disease states, including hypoxia and traumatic brain injury, impaired production of NO leads to vasoconstriction, platelet aggregation and oxidative stress. Resveratrol (trans-3,4’,5-trihydroxystilbene) is a polyphenolic compound found in peanuts, mulberries and red wine. It has been shown to display antioxidant activity, inhibit platelet aggregation and induce NO production. The purpose of the present study was to determine the effect of resveratrol on cultured brain endothelial cells in two models of pathology characterized by disrupted NO production – hypoxia alone and then a combination regimen of rapid stretch injury followed by hypoxia. Mouse brain endothelial cells cultured in resveratrol caused a dose-dependent increase in endothelial nitric oxide synthase (eNOS) protein expression. Importantly, resveratrol prevented hypoxia-induced decrease in eNOS expression. This was complemented by reduced cell death, as evidenced by a reduction in propidium iodide staining. However coincubation of resveratrol with the NO inhibitor, L-NAME, did not prevent this protection. Rapid stretch injury and hypoxia produced marked cell necrosis and resveratrol significantly inhibited this death. Our results suggest that resveratrol can prevent hypoxia-induced blunting of eNOS expression and protects endothelial cells from hypoxia alone and a combined regimen of rapid stretch injury and hypoxia.