Drug functionalized microbial polysaccharide based nanofibers as transdermal substitute.

In order to promote the natural healing process, drug-functionalized nanofibrous transdermal substitute was fabricated using gellan as chief polymer and polyvinyl alcohol (PVA) as supporting polymer via electrospinning technique. These fabricated nanofibers physiochemically mimic the extracellular matrix (ECM) which supports the cell growth. For neo-tissue regeneration in a sterilized environment, amoxicillin (Amx) was entrapped within these nanofibers. Entrapment of Amx in the nanofibers was confirmed by FESEM, FTIR, XRD and TG analysis. In vitro cell culture studies revealed that the fabricated non-cytotoxic nanofibers promoted enhance cell adherence and proliferation of human keratinocytes. A preliminary in vivo study performed on rat model for full thickness skin excision wound demonstrated the prompt re-epithelialization in early phase and quicker collagen deposition in later phases of wound healing in case of Amx-functionalized gellan/PVA nanofibers. Data collectively confirmed the potential usage of gellan based electrospun nanofibers as transdermal substitute for faster skin restoration.

Eucalyptol/ ß-cyclodextrin inclusion complex loaded gellan/PVA nanofibers as antifungal drug delivery system.

Fungal infections pose a serious threat to humankind due to the toxicity of conventional antifungal therapy and continuous emerging incidence of multidrug resistance. Essential oils fascinated researchers because of their broad antimicrobial activity and minimal cytotoxicity. However, hydrophobic, volatile and low water solubility of essential oils hinder their applications in pharmaceutical industries. Therefore, in this study we have loaded eucalyptol/ ß-cyclodextrin inclusion complex to gellan/polyvinyl alcohol nanofibers (EPNF) to eradicate Candida albicans and Candida glabrata biofilms. The electrospun nanofibers characterized by various physicochemical techniques and it was observed that EPNF possess highly hydrophilic surface property that facilitate rapid drug release. EPNF inhibited approximately 70% biofilm of C. albicans and C. glabrata. Time kill results depicted that eucalyptol (EPTL) encapsulation in the nanofibers prolonged its antifungal activity than the pure EPTL. Electron microscopy studies revealed that EPNF disrupted the cell surface of Candida. Collectively the current study suggested nanofiber encapsulation enhanced antibiofilm activity of eucalyptol and these nanoscale systems can serve as an alternative therapeutic strategy to treat fungal infections. Further, the developed nanofibrous materials can be applied as cost effective coating agent for biomedical implants.

Ofloxacin loaded gellan/PVA nanofibers - Synthesis, characterization and evaluation of their gastroretentive/mucoadhesive drug delivery potential.

The purpose of this investigation is to formulate a gastroretentive sustained drug release system for ofloxacin to improve its retention time, pharmacological activity, bioavailability and therapeutic efficacy in the stomach. Ofloxacin loaded gellan/poly vinyl alcohol (PVA) nanofibers were fabricated using a simple and versatile electrospinning technique. The fabricated nanofibers were evaluated for percent drug encapsulation efficiency and in vitro drug release in simulated gastric medium (pH1.2). The in vitro release profile and kinetic studies for drug indicated the sustained release of ofloxacin from the nanofibers through Fickian diffusion kinetics. The antimicrobial activity of the ofloxacin loaded nanofibers was assessed in comparison to the pure ofloxacin by means of minimal inhibitory concentrations (MIC) against microbial strains of Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The optimized ofloxacin loaded gellan/PVA nanofibers displayed biphasic drug release profile with considerable mucoadhesion and gastric retention in the rat's gastric mucosal membrane. Data obtained, suggested that the developed gastroretentive drug delivery can potentially enhance the pharmacological activity of ofloxacin and can also serve as a viable alternative for improving drug bioavailability via oral route.

Synthesis of PLGA nanoparticles of tea polyphenols and their strong in vivo protective effect against chemically induced DNA damage.

In spite of proficient results of several phytochemicals in preclinical settings, the conversion rate from bench to bedside is not very encouraging. Many reasons are attributed to this limited success, including inefficient systemic delivery and bioavailability under in vivo conditions. To achieve improved efficacy, polyphenolic constituents of black (theaflavin [TF]) and green (epigallocatechin-3-gallate [EGCG]) tea in poly(lactide-co-glycolide) nanoparticles (PLGA-NPs) were entrapped with entrapment efficacy of ~18% and 26%, respectively. Further, their preventive potential against 7,12-dimethylbenzanthracene (DMBA)-induced DNA damage in mouse skin using DNA alkaline unwinding assay was evaluated. Pretreatment (topically) of mouse skin with either TF or EGCG (100 µg/mouse) doses exhibits protection of 45.34% and 28.32%, respectively, against DMBA-induced DNA damage. However, pretreatment with TF-loaded PLGA-NPs protects against DNA damage 64.41% by 1/20th dose of bulk, 71.79% by 1/10th dose of bulk, and 72.46% by 1/5th dose of bulk. Similarly, 51.28% (1/20th of bulk), 57.63% (1/10th of bulk), and 63.14% (1/5th of bulk) prevention was noted using EGCG-loaded PLGA-NP doses. These results showed that tea polyphenol-loaded PLGA-NPs have ~30-fold dose-advantage than bulk TF or EGCG doses. Additionally, TF- or EGCG-loaded PLGA-NPs showed significant potential for induction of DNA repair genes (XRCC1, XRCC3, and ERCC3) and suppression of DNA damage responsive genes (p53, p21, MDM2, GADD45α, and COX-2) as compared with respective bulk TF or EGCG doses. Taken together, TF- or EGCG-loaded PLGA-NPs showed a superior ability to prevent DMBA-induced DNA damage at much lower concentrations, thus opening a new dimension in chemoprevention research.

Management of amlodipine-induced gingival enlargement: Series of three cases.

Gingival enlargement is one of the side effects associated with certain drugs. Amlodipine, a calcium channel blocker, used as antihypertensive drug has been found associated with gingival hyperplasia. This case series presents diagnosis and management of amlodipine-induced gingival hyperplasia. Amlodipine-induced gingival enlargement was diagnosed and managed by thorough scaling and root planning. Drug substitution and surgical intervention was performed in first two cases. The pathogenesis of gingival enlargement is uncertain and the treatment is still largely limited to the maintenance of an improved level of oral hygiene and surgical removal of the overgrown tissue. Several factors may influence the relationship between the drugs and gingival tissues as discussed by Seymour et al. Meticulous oral hygiene maintenance, switchover to alternative drug, professional scaling and root planning and surgical excision of enlarged gingival tissue may help overcome the effect of these drugs.