Design, Synthesis, Evaluation and Computational Studies of Nipecotic Acid-Acetonaphthone Hybrids as Potential Antiepileptic Agents.

BACKGROUND: Nipecotic acid is considered to be one of the most potent inhibitors of neuronal and glial γ-aminobutyric acid (GABA) uptake in vitro. However, nipecotic acid does not readily cross the blood-brain barrier (BBB) following peripheral administration, owing to its hydrophilic nature. OBJECTIVE: A series of substituted acetonaphthones tethered nipecotic acid derivatives were designed and synthesized with an aim to improve the lipophilicity and the blood-brain barrier (BBB) permeation. METHODS: Synthesized compounds were tested in mice models of PTZ, pilocarpine, and DMCM induced epilepsy, in vivo. The rota-rod test was performed to determine the acute neurotoxicity of the potential leads (4a, 4b, and 4i). These potential hybrids were also evaluated for their ability to cross the BBB by an in vitro parallel artificial membrane permeability BBB assay (PAMPA-BBB). The leads were subjected to in silico molecular docking and dynamics studies on homology modelled protein of human GABA (γ-amino butyric acid) transporter 1 (GAT1) and prediction of their pharmacokinetic properties. RESULT: Amongst the synthesized derivatives, compounds 3a, 3b, 3i, 4a, 4b, and 4i exhibited increased latency of seizures against subcutaneous pentylenetetrazole (scPTZ) induced seizures in mice. Derivatives 4a, 4b, 4i were more effective compared to nipecotic acid ester counterparts 3a, 3b and 3i placing the importance of the presence of free carboxyl group in the centre. The findings revealed that 4i was comparatively more permeable (Pe= 8.89) across BBB than the standard tiagabine (Pe= 7.86). In silico studies proved the consensual interactions of compound 4i with the active binding pocket. CONCLUSION: Some nipecotic acid-acetonaphthone hybrids with considerable anti-epileptic activity, drug like properties and the ability to permeate the BBB have been successfully synthesized.

Design, synthesis, evaluation and molecular modelling studies of some novel 5,6-diphenyl-1,2,4-triazin-3(2H)-ones bearing five-member heterocyclic moieties as potential COX-2 inhibitors: A hybrid pharmacophore approach.

A series of novel hybrids comprising of 1,3,4-oxadiazole/thiadiazole and 1,2,4-triazole tethered to 5,6-diphenyl-1,2,4-triazin-3(2H)-one were designed, synthesised and evaluated as COX-2 inhibitors for the treatment of inflammation. The synthesised hybrids were characterised using FT-IR, 1H NMR, 13C NMR, elemental (C,H,N) analyses and assessed for their anti-inflammatory potential by in vitro albumin denaturation assay. Compounds exhibiting activity comparable to indomethacin and celecoxib were further evaluated for in vivo anti-inflammatory activity. Oral administration of promising compounds 3c-3e and 4c-4e did not evoke significant gastric, hepatic and renal toxicity in rats. These potential compounds exhibited reduced malondialdehyde (MDA) content on the gastric mucosa suggesting their protective effects by inhibition of lipid peroxidation. Based on the outcome of in vitro COX assay, compounds 3c-3e and 4c-4e (IC50 0.60-1.11µM) elicited an interesting profile as competitive selective COX-2 inhibitors. Further, selected compounds 3e and 4c were found devoid of cardiotoxicity post evaluation on myocardial infarcted rats. The in silico binding mode of the potential compounds into the COX-2 active site through docking and molecular dynamics exemplified their consensual interaction and subsequent COX-2 inhibition with significant implications for structure-based drug design.

siRNA Therapy, Challenges and Underlying Perspectives of Dendrimer as Delivery Vector.

siRNA technology presents a helpful means of gene silencing in mammalian cells. Advancement in the field includes enhanced attentiveness in the characterization of target and off-target effects employing suitable controls and gene expression microarrays. These will permit expansion in the measurement of single and multiple target combinations and also permit comprehensive efforts to understand mammalian cell processes. Another fact is that the delivery of siRNA requires the creation of a nanoparticulate vector with controlled structural geometry and surface modalities inside the targeted cells. On the other hand, dendrimers represent the class of carrier system where massive control over size, shape and physicochemical properties makes this delivery vector exceptional and favorable in genetic transfection applications. The siRNA therapeutics may be incorporated inside the geometry of the density controlled dendrimers with the option of engineering the structure to the specific needs of the genetic material and its indication. The existing reports on the siRNA carrying and deliverance potential of dendrimers clearly suggest the significance of this novel class of polymeric architecture and certainly elevate the futuristic use of this highly branched vector as genetic material delivery system.

Nanocarriers Assisted siRNA Gene Therapy for the Management of Cardiovascular Disorders.

Cardiovascular diseases (CVDs), primarily myocardial infarction (MI), atherosclerosis, hypertension and congestive heart failure symbolize the foremost cause of death in almost all parts of the world. Besides the traditional therapeutic approaches for the management of CVDs, newer innovative strategies are also emerging on the horizon. Recently, gene silencing via small interfering RNA (siRNA) is one of the hot topics amongst various strategies involved in the management of CVDs. The siRNA mechanism involves natural catalytic processes to silence pathological genes that are overexpressed in a particular disease. Also the versatility of gene expression by siRNA deciphers a prospective tactic to down-regulate diseases associated gene, protein or receptor existing on a specific disease target. This article reviews the application of siRNA against CVDs with special emphasis on gene targets in combination with delivery systems such as cationic hydrogels, polyplexes, peptides, liposomes and dendrimers.

Nanomaterial Based Approaches for the Diagnosis and Therapy of Cardiovascular Diseases.

The increasing prevalence and complexity of cardiovascular diseases demand innovative strategies for diagnostic and therapeutic applications to improve patient care/prognoses. Additionally, various factors constrain present cardiovascular therapies, including low aqueous drug solubility, early metabolism, short half-life and drug delivery limitations. The efficient treatment of cardiovascular diseases requires improvement of traditional drug delivery systems. This can be accomplished by using novel nanomaterial that can incorporate diverse bio-actives along with diagnostic agents in a single carrier, referred to as theranostics. This review discusses the state of the art in the applications to diagnosis and therapy of innovative, nanomaterial- based strategies such as lipid based carriers, nanocapsules, magnetic nanoparticles, gold nanoparticles, protein conjugated nanoparticles, dendrimers and carbon-based nanoformulations with a special emphasis on how they can contribute to improving the management of cardiovascular disease.

Ethosomes and ultradeformable liposomes for transdermal delivery of clotrimazole: A comparative assessment.

THE OBJECTIVE OF WORK WAS TO FORMULATE, EVALUATE AND COMPARE THE TRANSDERMAL POTENTIAL OF NOVEL VESICULAR NANOCARRIERS: ethosomes and ultradeformable liposomes, containing clotrimazole (CLT), an anti-fungal bioactive. The ethosomal formulation (ET4) and ultradeformable liposomal (UL) formulation (TT3) showed highest entrapment 68.73 ± 1.4% and 55.51 ± 1.7%, optimal nanometric size range 132 ± 9.5 nm and 121 ± 9.7 nm, and smallest polydispersity index 0.027 ± 0.011 and 0.067 ± 0.009, respectively. The formulation ET4 provided enhanced transdermal flux 56.25 ± 5.49 µg/cm(2)/h and decreased the lag time of 0.9 h in comparison to TT3 formulation (50.16 ± 3.84 µg/cm(2)/h; 1.0 h). Skin interaction and FT-IR studies revealed greater penetration enhancing effect of ET4 than TT3 formulation. ET4 formulation also had the highest zone of inhibition (34.6 ± 0.57 mm), in contrast to TT3 formulation (29.6 ± 0.57 mm) and marketed cream formulation (19.0 ± 1.00 mm) against candidal species. Results suggested ethosomes to be the most proficient carrier system for dermal and transdermal delivery of clotrimazole.