Azmat Ali Khan

Antimicrobial activity of clove oil and its potential in the treatment of vaginal candidiasis

In the present study, we evaluated antimicrobial activity of clove oil against a range of fungal pathogens including that responsible for urogenital infection. Clove oil was found to possess strong antifungal activity against opportunistic fungal pathogens such as Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus, etc. The oil was found to be extremely successful in the treatment of experimental murine vaginitis in model animals. On evaluating various formulations, topical administration of the liposomized clove oil was found to be most effective against treatment of vaginal candidiasis.

Synthesis and characterization of novel PUFA esters exhibiting potential anticancer activities: An in vitro study

Polyunsaturated fatty acids (PUFAs) have been reported to play a regulatory role in tumour growth progression. In the present study, we have synthesized ester derivatives of two important PUFA viz., linoleic acid (LA) and arachidonic acid (AA) with propofol, a widely used general anaesthetic-sedative agent. The novel propofol ester analogues have been found to inhibit various cancer cell lines in a dose-dependent manner. Moreover, the compounds have been found to induce apoptotic cell death by enhancing the release of cytochrome c and expression of caspase-3. The data of the present study suggest that novel propofol-PUFA esters have strong potential to emerge as effective anticancer agents.

Synthesis and Characterization of Novel n-9 Fatty Acid Conjugates Possessing Antineoplastic Properties

The present study enumerates the synthesis, spectroscopic characterization, and evaluation of anticancer potential of esters of two n-9 fatty acids viz., oleic acid (OLA) and ricinoleic acid (RCA) with 2,4- or 2,6-diisopropylphenol. The synthesis strategy involved esterification of the hydroxyl group of diisopropylphenol (propofol) to the terminal carboxyl group of n-9 fatty acid. The synthesized propofol-n-9 conjugates having greater lipophilic character were tested initially for cytotoxicity in-vitro. The conjugates showed specific growth inhibition of cancer cell lines whereas no effect was observed in normal cells. In general, pronounced growth inhibition was found against the human skin malignant melanoma cell line (SK-MEL-1). The anticancer potential was also determined by testing the effect of these conjugates on cell migration, cell adhesion and induction of apoptosis in SK-MEL-1 cancer cells. Propofol-OLA conjugates significantly induced apoptosis in contrast to propofol-RCA conjugates which showed only weak signals for cytochrome c. Conclusively, the synthesized novel ester conjugates showed considerable moderation of anti-tumor activity. This preliminary study places in-house synthesized conjugates into the new class of anticancer agents that possess selectivity toward cancer cells over normal cells.

Synthesis and characterization of 2-substituted benzimidazoles and their evaluation as anticancer agent.

In this work, we report a series of benzimidazole derivatives synthesized from benzene-1,2-diamine and aryl-aldehydes at room temperature. The synthesized compounds have been characterized on the basis of elemental analysis and various spectroscopic studies viz., IR, (1)H- and (13)C-NMR, ESI-MS as well by X-ray single X-ray crystallographic study. Interaction of these compounds with CT-DNA has been examined with fluorescence experiments and showed significant binding ability. All the synthesized compounds have been screened for their antitumor activities against various human cancer cell lines viz., Human breast adenocarcinoma cell line (MCF-7), Human leukemia cell line (THP-1), Human prostate cancer cell lines (PC-3) and adenocarcinomic human alveolar basal epithelial cell lines (A-549). Interestingly, all the compounds showed significant anticancer activity.

Efficacy of amoxicillin bearing microsphere formulation in treatment of Listeria monocytogenes infection in Swiss albino mice.

The present study deals with the evaluation of the efficacy of amoxicillin bearing poly-lactic-glycolic acid (PLGA) microsphere formulation in treatment of experimental listeriosis in Swiss albino mice. Amoxicillin bearing PLGA microspheres were prepared by water-in-oil-in-water emulsion technique. PLGA microwspheres significantly regulated sustained release of encapsulated drug over extended time period. The rate of release increased in temperature dependent manner. Amoxicillin bearing PLGA microsphere successfully cleared bacterial burdens in vital organs (kidney, spleen, and brain) and also increased survival rate of treated animals in comparison to free form of the drug. The higher efficacy of microsphere based novel formulation of amoxicillin could be attributed to its targeted delivery to infected macrophages as well as sustained release over extended period of time.

Molecular modeling and analysis of hepatitis E virus (HEV) papain-like cysteine protease.

Abstract The biochemical or biophysical characterization of a papain-like cysteine protease in HEV ORF1-encoded polyprotein still remains elusive. Very recently, we have demonstrated the indispensability of ORF1 protease-domain cysteines and histidines in HEV replication, ex vivo (Parvez, 2013). In this report, the polyprotein partial sequences of HEV strains and genetically-related RNA viruses were analyzed, in silico. Employing the consensus-prediction results of RUBV-p150 protease as structural-template, a 3D model of HEV-protease was deduced. Similar to RUBV-p150, a ‘papain-like β-barrel fold’ structurally confirmed the classification of HEV-protease. Further, we recognized a catalytic ‘Cys434-His443’ dyad homologue of RUBV-p150 (Cys1152-His1273) and FMDV-Lpro (Cys51-His148) in line with our previous mutational analysis that showed essentiality of ‘His443’ but not ‘His590’ in HEV viability. Moreover, a RUBV ‘Zn2+ binding motif’ (Cys1167-Cys1175-Cys1178-Cys1225-Cys1227) equivalent of HEV was identified as ‘Cys457-His458-Cys459 and Cys481-Cys483’ residues within the ‘β-barrel fold’. Notably, unlike RUBV, ‘His458’ also clustered therein, that was in conformity with the consensus cysteine protease ‘Zn2+-binding motif’. By homology, we also proposed an overlapping ‘Ca2+-binding site’ ‘D-X-[DNS]-[ILVFYW]-[DEN]-G-[GP]-XX-DE’ signature, and a ‘proline-rich motif’ interacting ‘tryptophan (W437-W472)’ module in the modeled structure. Our analysis of the predicted model therefore, warrants critical roles of the ‘catalytic dyad’ and ‘divalent metal-binding motifs’ in HEV protease structural-integrity, ORF1 self-processing, and RNA replication. This however, needs further experimental validations.

HPLC method with monolithic column for simultaneous determination of irbesartan and hydrochlorothiazide in tablets

Abstract A simple, sensitive and accurate HPLC method with high throughput has been developed and validated for the simultaneous determination of irbesartan (IRB) and hydrochlorothiazide (HCT) in combined pharmaceutical dosage forms. The proposed method employed, for the first time, a monolithic column in the analysis. Optimal chromatographic separation of the analytes was achieved on Chromolith® Performance RP-18e column using a mobile phase consisting of phosphate buffer (pH 4)/acetonitrile (50:50, V/V) pumped isocratically at a flow rate of 1.0 mL min-1. The eluted analytes were monitored with a UV detector set at 270 nm. Under the optimum chromatographic conditions, linear relationship with a good correlation coefficient (R ≥ 0.9997) was found between the peak area and the corresponding concentrations of both IRB and HCT in the ranges of 10-200 and 1-20 ng mL-1. The limits of detection were 2.34 and 0.03 ng mL-1 for IRB and HCT, respectively. The intra- and inter-assay precisions were satisfactory as the RSD values did not exceed 3 %. The accuracy of the proposed method was > 97 %. The proposed method had high throughput as the analysis involved a simple procedure and a very short run- -time of < 3 min. The results demonstrated that the method is applicable in the quality control of combined pharmaceutical tablets containing IRB and HCT

Anticancer efficacy of a novel propofol–linoleic acid-loaded escheriosomal formulation against murine hepatocellular carcinoma

AIM The preparation and characterization of a novel escheriosomal nanoparticle formulation of a potent anticancer conjugate, 2,6-diisopropylphenol-linoleic acid (2,6P-LA), and evaluation of its anticancer efficacy against diethyl nitrosamine-induced hepatocellular carcinoma (HCC) in BALB/c mice. MATERIALS & METHODS Escheriosomized 2,6P-LA nanoparticles were characterized for size, zeta-potential, entrapment efficiency, release kinetics and in vivo toxicity. Their anticancer potential was evaluated on the basis of survival, DNA fragmentation, caspase-3 activation, western blot analysis of apoptotic factors and histopathological changes in hepatocytes of treated animals. RESULTS The escheriosomized 2,6P-LA nanoparticles exhibited low toxicity, biocompatibility and bioavailability. As revealed by apoptosis induction, survival rate, expression profiles of Bax, Bcl-2 and caspase-9, escheriosomized 2,6P-LA nanoparticles were more effective in the treatment of HCC than the free form of 2,6P-LA in experimental animals. CONCLUSION 2,6P-LA-bearing escheriosome nanoparticles are effective in suppressing HCC in mice. Original submitted 17 January 2012; Revised submitted 27 August 2012; Published online 14 January 2013.

In vitro evaluation of cytotoxicity, possible alteration of apoptotic regulatory proteins, and antibacterial activity of synthesized copper oxide nanoparticles

Copper oxide nanoparticles (CuO-NPs) were synthesized using a urea-based thermal decomposition technique, and characterized using different techniques. X-ray diffraction (XRD) and Raman spectroscopy confirmed the phase purity and crystalline structure of CuO-NPs. The size of CuO-NPs was investigated using XRD and was confirmed via dynamic light scattering analysis. CuO-NPs showed an average diameter of ∼20nm. The possible cytotoxicity of CuO-NPs was evaluated in HT-29 and SW620 cancer cell lines. The median inhibitory concentration of CuO-NPs in HT-29 and SW-620 cells was 4.99 and 3.75μg/mL, respectively. The underlying mechanism responsible for apoptosis in colon cancer cells after CuO-NP exposure has not been well understood. In this study, we investigated the possible mechanisms of induction of apoptosis via analysis of the expression of Bcl-2 and Bcl-xL proteins in HT-29 human colon cancer cells after CuO-NP exposure. Western blot assay showed downregulation of Bcl-2 and Bcl-xL protein expression after CuO-NP exposure. Our findings may aid in the understanding of the potential mechanisms responsible for induction of apoptosis owing to inhibition of Bcl-2 and Bcl-xL protein expression. Furthermore, the antibacterial activity assay showed that the synthesized CuO-NPs did not exert significant inhibitory effects against different gram-positive and gram-negative bacteria in vitro.

Vaccine potential of cytosolic proteins loaded fibrin microspheres of Cryptococcus neoformans in BALB/c mice

Cryptococcosis is a leading mycological cause of mortality among immunologically compromised individuals. In order to develop an effective vaccine against Cryptococcus neoformans, the cytosolic proteins (Cp) of the pathogen have been used as an antigen in combination with different formulations. In the present study, we have demonstrated that Cp encapsulated poly-lactide co-glycolide (PLGA) microsphere further co-encapsulated into the biocompatible fibrin cross-linked plasma beads (Fib-PLGA-Cp) mediated cytosolic delivery elicited strong immune response in the BALB/c mice. In contrast, other formulations of Cp failed to impart significant level of protection. The immune response, involved with Fib-PLGA-Cp protection, appear to interact with the target cells by both endocytosis as well as membrane fusion mode, thus helping in the activation of both CD4+ and CD8+ T-cells. Analysis of cytokine profiles in immunized animals revealed that the protective response was associated with the Th1/Th2 polarization in favor of type-1 cytokine [interferons (IFN)-γ and interleukin (IL)-2] cells. Furthermore, vaccination with Fib-PLGA-Cp elicited high immunoglobulin (Ig) Gl and IgG2a isotype response; successfully cleared fungal burden in vital organs and also increased the survival rate of immunized animals. Altogether the present study is a clear indicative of the possible use of fibrin microsphere-based targeted delivery of cytosolic proteins to induce protective immune responses against experimental murine cryptococcosis.