Ramesh Chandra

Publications of Ramesh Chandra

• Implications of Nanoscale Based Drug Delivery Systems in Delivery and Targeting Tubulin Binding Agent, Noscapine in Cancer Cells.

  Authors: Ramesh Chandra, Jitender Madan, Prashant Singh, Ankush Chandra, Pradeep Kumar, Vritika Tomar, Sujata K Dass

  Current drug metabolism. 05/2012;

  Noscapine, a tubulin binding anticancer agent undergoing Phase I/II clinical trials, inhibits tumor growth in nude mice bearing human xenografts of breast, lung, ovarian, brain, and prostrate origin.Noscapine, a tubulin binding anticancer agent undergoing Phase I/II clinical trials, inhibits tumor growth in nude mice bearing human xenografts of breast, lung, ovarian, brain, and prostrate origin. The analogues of noscapine like 9-bromonoscapine (EM011) is 5 to 10-fold more active than parent compound, noscapine. Noscapinoids inhibit the proliferation of cancer cells that are resistant to paclitaxel and epothilone. Noscapine also potentiated the anticancer activity of doxorubicin in a synergistic manner against triple negative breast cancer (TNBC). However, physicochemical and pharmacokinetic (ED50~300-600 mg/kg bodyweight) limitations of noscapine present hurdle in development of commercial anticancer formulations. Therefore, objectives of the present review are to summarize the chemotherapeutic potential of noscapine and implications of nanoscale based drug delivery systems in enhancing the therapeutic efficacy of noscapine in cancer cells. We have constructed noscapine-enveloped gelatin nanoparticles, NPs and poly (ethylene glycol) grafted gelatin NPs as well as inclusion complex of noscapine in β-cyclodextrin (β-CD) and evaluated their physicochemical characteristics. The Fe3O4 NPs were also used to prepare noscapine loaded magnetic polymeric NPs (NMNP) which encapsulate the noscapine on the surface of the polymer matrix, whereas the molecular weight of polymer plays a crucial role in the capacity of drug loading on the polymer surface. The enhanced noscapine delivery using µPAR-targeted optical-MR imaging trackable NPs offer a great potential for image directed targeted delivery of noscapine. Human Serum Albumin NPs (150-300 nm) as efficient noscapine drug delivery systems have also been developed for potential use in breast cancer.

• Galactosylated gelatin nanovectors of doxorubicin inhibit cell proliferation and induce apoptosis in hepatocarcinoma cells.

  Authors: Monika Garg, Jitender Madan, Ravi Shankar Pandey, Satish Sardana, Anju Katyal, Ramesh Chandra

  Anti-cancer drugs. 03/2012;

  We have synthesized and characterized doxorubicin (DOX)-loaded galactosylated gelatin nanovectors using in vitro and in vivo for targeting liver cells including hepatocarcinoma cells. GalactosylatedWe have synthesized and characterized doxorubicin (DOX)-loaded galactosylated gelatin nanovectors using in vitro and in vivo for targeting liver cells including hepatocarcinoma cells. Galactosylated and nongalactosylated gelatin nanovectors (GL-GN-DOX and GN-DOX) were spherical in shape and had mean sizes of about 95.1 and 88.3 nm, respectively. In-vitro release of DOX from nanovectors followed first-order kinetics and was pH dependent. Galactosylated formulation released 95.2% of DOX compared with 86.6% by nongalactosylated formulation at pH 5.8. However, the release rate was suppressed at pH 7.4. Further, we showed that GL-GN-DOX had greater growth inhibitory effect on HepG2 in terms of low inhibitory concentration (IC50; 0.35 µg/ml) compared with GN-DOX (0.75 µg/ml) and induced caspase-3-mediated apoptosis in HepG2 cells. This might be due to efficient internalization of galactosylated nanovectors by HepG2 cells compared with unmodified formulation. Pharmacokinetic and biodistribution analyses show that galactosylated formulation deposits 24.5 µg/g of DOX in targeted tissue (liver) in comparison with heart (0.3 µg/g) at a single dose of 10 mg/kg. These results suggest that DOX-loaded galactosylated gelatin nanovectors warrant future in-depth antitumor study to scale-up technology and may be used for the management of hepatocarcinoma.

• Cationic polymer based nanocarriers for delivery of therapeutic nucleic acids.

  Authors: Surendra Nimesh, Nidhi Gupta, Ramesh Chandra

  Journal of biomedical nanotechnology. 08/2011; 7(4):504-20.

  The design and development of nucleic acids based therapeutics for the treatment of diseases arising from genetic abnormalities has made significant progress over the past few years. Advances inThe design and development of nucleic acids based therapeutics for the treatment of diseases arising from genetic abnormalities has made significant progress over the past few years. Advances in synthetic oligonucleotide chemistry resulted in synthesis of nucleic acids that are relatively stable in in vivo environments. However, cellular targeting and intracellular delivery of nucleic acids still remains a challenge. Further, development of nucleic acids based therapeutics depends on the progress of safe and effective carriers for systemic administration. Cationic vectors with diminished cytotoxicity and enhanced efficacy are rapidly emerging as systems of choice. These vectors protect nucleic acids from enzymatic degradation by forming condensed complexes along with targeted tissue and cellular delivery. During the past few years, myriad of reports have appeared reporting delivery of nucleic acids mediated by nanocarriers. This review provides an overview of various nanocarriers employed for in vitro and in vivo delivery of therapeutically relevant nucleic acids e.g., DNA, siRNA, LNA, PNA etc.

• Strategies and advances in nanomedicine for targeted siRNA delivery.

  Authors: Surendra Nimesh, Nidhi Gupta, Ramesh Chandra

  Nanomedicine (London, England). 06/2011; 6(4):729-46.

  siRNA are a rapidly emerging class of new therapeutic molecules for the treatment of inherited and acquired diseases. However, poor cellular uptake and instability in physiological conditions limitssiRNA are a rapidly emerging class of new therapeutic molecules for the treatment of inherited and acquired diseases. However, poor cellular uptake and instability in physiological conditions limits its therapeutic potential, hence a need to develop a delivery system that can protect and efficiently transport siRNA to the target cells has arisen. Nanoparticles have been proposed as suitable delivery vectors with reduced cytotoxicity and enhanced efficacy. These delivery vectors form condensed complexes with siRNA which, in turn, provides protection to siRNA against enzymatic degradation and further leads to tissue and cellular targeting. Nanoparticles derived from polymers, such as chitosan and polyethylenimine have found numerous applications owing to ease of manipulation, high stability, low cost and high gene carrying capability. This article focuses on various aspects of nanomedicine based siRNA delivery with emphasis on targeted delivery to tumors.

• Rational design, synthesis and biological evaluations of amino-noscapine: a high affinity tubulin-binding noscapinoid.

  Authors: Pradeep K Naik, Biswa Prasun Chatterji, Surya N Vangapandu, Ritu Aneja, Ramesh Chandra, Srinivas Kanteveri, Harish C Joshi

  Journal of computer-aided molecular design. 05/2011; 25(5):443-54.

  Noscapine and its derivatives are important microtubule-interfering agents shown to have potent anti-tumor activity. The binding free energies (ΔG (bind)) of noscapinoids computed using linearNoscapine and its derivatives are important microtubule-interfering agents shown to have potent anti-tumor activity. The binding free energies (ΔG (bind)) of noscapinoids computed using linear interaction energy (LIE) method with a surface generalized Born (SGB) continuum solvation model were in agreement with the experimental ΔG (bind) with average root mean square error of 0.082 kcal/mol. This LIE-SGB model guided us in designing a novel derivative of noscapine, amino-noscapine [(S)-3-((R)-9-amino-4-methoxy-6-methyl-5,6,7,8-tetrahydro [1, 3] dioxolo[4,5-g]isoquinolin-5-yl)-6,7-dimethoxy isobenzo-furan-1(3H)-one] that has higher tubulin binding activity (predicted ΔG (bind) = -6.438 kcal/mol and experimental ΔG (bind) = -6.628 kcal/mol) than noscapine, but does not significantly change the total extent of the tubulin subunit/polymer ratio. The modes of interaction of amino-noscapine with the binding pocket of tubulin involved three hydrogen bonds and are distinct compared to noscapine which involved only one hydrogen bond. Also the patterns of non-bonded interactions are albeit different between both the lignads. The 'blind docking' approach (docking of ligand with different binding sites of a protein and their evaluations) as well as the reasonable accuracy of calculating ΔG (bind) using LIE-SGB model constitutes the first evidence that this class of compounds binds to tubulin at a site overlapping with colchicine-binding site or close to it. Our results revealed that amino-noscapine has better anti-tumor activity than noscapine.

• Long-circulating poly(ethylene glycol)-grafted gelatin nanoparticles customized for intracellular delivery of noscapine: preparation, in-vitro characterization, structure elucidation, pharmacokinetics, and cytotoxicity analyses.

  Authors: Jitender Madan, Neerupma Dhiman, Satish Sardana, Ritu Aneja, Ramesh Chandra, Anju Katyal

  Anti-cancer drugs. 04/2011; 22(6):543-55.

  Noscapine, the tubulin-binding anticancer agent, when administered orally, requires high ED(50) (300-600 mg/kg), whereas intravenous administration (10 mg/kg) results in rapid elimination of the drugNoscapine, the tubulin-binding anticancer agent, when administered orally, requires high ED(50) (300-600 mg/kg), whereas intravenous administration (10 mg/kg) results in rapid elimination of the drug with a half-life of 0.39 h. Hence, the development of long-circulating injectable nanoparticles can be an interesting option for designing a viable formulation of noscapine for anticancer activity. Noscapine-enveloped gelatin nanoparticles and poly(ethylene glycol)-grafted gelatin nanoparticles were constructed and characterized. Data indicate that smooth and spherical shaped nanoparticles of 127 ± 15 nm were engineered with maximum entrapment efficiency of 65.32 ± 3.81%. Circular dichroism confirms that nanocoacervates retained the α-helical content of gelatin in ethanol whereas acetone favored the formation of a random coil. Moreover, the Fourier transform infrared and powder X-ray diffraction pattern prevents any significant change in the noscapine-loaded gelatin nanoparticles in comparison with individual components. In-vitro release kinetic data suggest a first-order release of noscapine (85.1%) from gelatin nanoparticles with a release rate constant of 7.611×10(-3). It is to be noted that there is a 1.43-fold increase in the area under the curve up to the last sampling point for the noscapine-loaded poly(ethylene glycol)-grafted gelatin nanoparticles over the noscapine-loaded gelatin nanoparticles and a 13.09-fold increase over noscapine. Cytotoxicity analysis of the MCF-7 cell line indicated that the IC(50) value of the noscapine-loaded poly(ethylene glycol)-grafted gelatin nanoparticles was equivalent to 20.8 μmol/l, which was significantly (P<0.05) lower than the IC(50) value of the noscapine-loaded gelatin nanoparticles (26.3 μmol/l) and noscapine (40.5 μmol/l).Noscapine-loaded poly(ethylene glycol)-grafted gelatin nanoparticles can be developed as a promising therapeutic agent for the management of breast cancer.

• A rapid and simple route for the synthesis of lead and palladium nanoparticles in tetrazolium based ionic liquid.

  Authors: Prashant Singh, Pradeep Kumar, Kamlesh Kumari, Pankaj Sharma, Subho Mozumdar, Ramesh Chandra

  Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy. 02/2011; 78(2):909-12.

  In the present work, we report a novel method for the synthesis of palladium and lead nanoparticles by the reduction method in tetrazolium ring based ionic liquid. Palladium and lead nanoparticlesIn the present work, we report a novel method for the synthesis of palladium and lead nanoparticles by the reduction method in tetrazolium ring based ionic liquid. Palladium and lead nanoparticles so-prepared were well characterized by powder X-ray diffraction measurements (pXRD), transmission electron microscopy (TEM) and quasi elastic light scattering (QELS) techniques. Powder X-ray diffraction (pXRD) analysis revealed all relevant Bragg's reflection for crystal structure of palladium and lead. Powder X-ray diffraction plots also revealed no oxidized material of palladium and lead nanoparticles. TEM showed nearly uniform distribution of the particles in methanol and confirmed by QELS. Typical applications of palladium nanoparticles include in vitro use and sensor design applications. Palladium nanoparticles is also ideal for spin coating, self-assembly and monolayer formation. Palladium nanoparticles can also be considered as potential new catalysts.

• Insulinotropic effect of cinnamaldehyde on transcriptional regulation of pyruvate kinase, phosphoenolpyruvate carboxykinase, and GLUT4 translocation in experimental diabetic rats.

  Authors: Prachi Anand, K Y Murali, Vibha Tandon, P S Murthy, Ramesh Chandra

  Chemico-biological interactions. 04/2010; 186(1):72-81.

  Diabetes mellitus is a chronic metabolic disorder affecting about 6% of population worldwide with its complications and is rapidly reaching epidemic scale. Cinnamomum zeylanicum is widely used inDiabetes mellitus is a chronic metabolic disorder affecting about 6% of population worldwide with its complications and is rapidly reaching epidemic scale. Cinnamomum zeylanicum is widely used in alternative system of medicine for treatment of diabetes. In the present study, we have performed bioassay guided fractionation of chloroform extract of C. zeylaniucm and identified cinnamaldehyde (CND) as an active principle against diabetes. In continuation to it, a detailed study was undertaken to elucidate its mode of antidiabetic action in STZ induced diabetic rats. Oral administration of CND (20 mg/kg bw) to diabetic rats for 2 months showed significant improvement (p<0.001) in muscle and hepatic glycogen content. In vitro incubation of pancreatic islets with CND enhanced the insulin release compared to glibenclamide. The insulinotropic effect of CND was found to increase the glucose uptake through glucose transporter (GLUT4) translocation in peripheral tissues. The treatment also showed a significant improvement in altered enzyme activities of pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK) and their mRNA expression levels. Furthermore, the median lethal dose (LD(50)) of CND could not be obtained even at 20 times (0.4 g/kg bw) of its effective dose. With the high margin of safety of CND, it can be developed as a potential therapeutic candidate for the treatment of diabetes.

• Synthesis and electrochemical studies of charge-transfer complexes of thiazolidine-2,4-dione with sigma and pi acceptors.

  Authors: Prashant Singh, Pradeep Kumar, Anju Katyal, Rashmi Kalra, Sujata K Dass, Satya Prakash, Ramesh Chandra

  Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy. 03/2010; 75(3):983-91.

  In the present work, we report the synthesis and characterization of novel charge-transfer complexes of thiazolidine-2,4-dione (TZD) with sigma acceptor (iodine) and pi acceptors (chloranil,In the present work, we report the synthesis and characterization of novel charge-transfer complexes of thiazolidine-2,4-dione (TZD) with sigma acceptor (iodine) and pi acceptors (chloranil, dichlorodicyanoquinone, picric acid and duraquinone). We also evaluated their thermal and electrochemical properties and we conclude that these complexes are frequency dependent. Charge-transfer complex between thiazolidine-2,4-dione and iodine give best conductivity. In conclusion, complex with sigma acceptors are more conducting than with pi acceptors.

• Synthesis and characterization of silver and gold nanoparticles in ionic liquid.

  Authors: Prashant Singh, Kamlesh Kumari, Anju Katyal, Rashmi Kalra, Ramesh Chandra

  Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy. 08/2009; 73(1):218-20.

  In this paper, we report the reduction of silver and gold salts by methanolic solution of sodium borohydride in tetrazolium based ionic liquid as a solvent at 30 degrees C leads to pure phase ofIn this paper, we report the reduction of silver and gold salts by methanolic solution of sodium borohydride in tetrazolium based ionic liquid as a solvent at 30 degrees C leads to pure phase of silver and gold nanoparticles. Silver and gold nanoparticles so-prepared were well characterized by powder X-ray diffraction measurements (XRD), transmission electron microscopy (TEM) and QELS. XRD analysis revealed all relevant Bragg's reflection for crystal structure of silver and gold metal. XRD spectra also revealed no oxidation of silver nanoparticles to silver oxide. TEM showed nearly uniform distribution of the particles in methanol and it was confirmed by QELS. Silver and gold nanoparticles in ionic liquid can be easily synthesized and are quite stable too.

• Inclusion complexes of noscapine in beta-cyclodextrin offer better solubility and improved pharmacokinetics.

  Authors: Jitender Madan, Neerupma Dhiman, Vinod Parmar, Satish Sardana, Prasad Bharatam, Ritu Aneja, Ramesh Chandra, Anju Katyal

  Cancer chemotherapy and pharmacology. 08/2009;

  PURPOSE: Noscapine (NOS) is a unique class of tubulin-binding anticancer agents. Their potential usefulness as anticancer drugs is however limited by the poor bioavailability, thus necessitatingPURPOSE: Noscapine (NOS) is a unique class of tubulin-binding anticancer agents. Their potential usefulness as anticancer drugs is however limited by the poor bioavailability, thus necessitating administration of a higher dose regime in the range of 300-600 mg/kg for tumor growth inhibition. To augment bioavailability, we prepared an inclusion complex of NOS in beta-cyclodextrin (beta-CD) and evaluated its physico-chemical characteristics. METHOD AND RESULTS: Our phase-solubility analysis shows a 1:1-complexation (K ( c ) ~0.454 mM(-1)) of NOS with beta-CD that offers better dissolution properties. We confirmed complex formation in solid state by differential scanning calorimetry, powder X-ray diffractometry, Fourier-transform infrared spectroscopy, (1)H nuclear magnetic resonance spectroscopy, rotating frame Overhauser enhancement spectroscopy and by molecular modeling methods. Based upon theoretical calculations in gas phase, we propose O-CH(2)-O- in orientation of NOS in the beta-CD cavity. The thermal behavior data also provides complementary evidences of complex formation. The pharmacokinetic studies showed a 1.87-fold increase in bioavailability of NOS upon complexation in the beta-CD inclusion complex state as compared to free NOS. Furthermore, the complex retains the anticancer attributes of NOS. CONCLUSION: Our studies propose for the first time a stable NOS-beta-CD inclusion complex as an effective approach to enhance the solubility and bioavailability of NOS for anticancer therapy.

• Epileptic seizure-induced hypertension and its prevention by calcium channel blockers: a real-time study in conscious telemetered rats.

  Authors: Mirza Irfan Beig, Ramesh Chandra, Anita Talwar, Mohammad Fahim, Anju Katyal

  Canadian journal of physiology and pharmacology. 07/2009; 87(7):572-80.

  Epileptic seizures are accompanied by changes in autonomic function that in turn influence the cardiovascular system (hypertension and bradyarrhythmia). We have studied possible cardioprotectiveEpileptic seizures are accompanied by changes in autonomic function that in turn influence the cardiovascular system (hypertension and bradyarrhythmia). We have studied possible cardioprotective activity (during the ictal state in conscious animals) of valproic acid, nifedipine, and verapamil, alone and in combination, during pentylenetetrazole (PTZ)-induced seizures. Telemetry system was used for recording EEG, blood pressure, and heart rate in conscious, freely moving rats during seizures. We observed that PTZ-induced seizures were accompanied by hypertension and bradyarrhythmia. Pretreatment with valproic acid did not block seizure-induced hypertension and bradyarrhythmia. Nifedipine alone and in combination with valproic acid blocked seizure-induced hypertension and bradyarrhythmia significantly. We also observed that pretreatment with verapamil alone and in combination with valproic acid did not block seizure-induced hypertension and bradyarrhythmia significantly. Our results suggest that pretreatment with nifedipine alone or in combination with valproic acid provides protection against seizure-induced hypertension and bradyarrhythmia.

• Polyethylenimine nanoparticles as an efficient in vitro siRNA delivery system.

  Authors: Surendra Nimesh, Ramesh Chandra

  European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V. 05/2009;

  Degradation of mRNA by RNA interference is of the most powerful and specific mechanism for gene silencing. Owing to this property, siRNAs are emerging as promising therapeutic agents for theDegradation of mRNA by RNA interference is of the most powerful and specific mechanism for gene silencing. Owing to this property, siRNAs are emerging as promising therapeutic agents for the treatment of inherited and acquired diseases, as well as research tools for the elucidation of gene function in both health and disease. Here we have explored the potential of polyethylenimine (PEI) to deliver siRNA to mammalian cells. Nanoparticles of PEI were prepared by acylating PEI with propionic anhydride followed by cross-linking with polyethylene glycol-bis (phosphate). The nanoparticles size as revealed by DLS studies was found to be approximately 110nm and AFM investigations showed spherical and compact complexes with an average size of 100nm. For electro-neutralization of negative charge of siRNA higher amount of nanoparticles was required as compared to native PEI. The siRNA delivery efficiency of nanoparticles was assessed by using siRNA against gene coding for green fluorescent protein (GFP). The gene silencing efficiency of PEI nanoparticles was found to be comparable to commercially available transfecting agent Lipofectin but with reduced cytotoxicity.

• The effect of the aqueous extract of the roots of Asparagus racemosus on hepatocarcinogenesis initiated by diethylnitrosamine.

  Authors: Alka Agrawal, Meenakshi Sharma, Santosh Kumar Rai, Bharat Singh, Manisha Tiwari, Ramesh Chandra

  Phytotherapy research : PTR. 09/2008; 22(9):1175-82.

  Histopathological studies of the hepatic tissues of Wistar rats treated with diethylnitrosamine (DEN) (200 mg/kg b wt, i.p.) once a week for 2 weeks, followed by treatment with DDT, a tumor promoterHistopathological studies of the hepatic tissues of Wistar rats treated with diethylnitrosamine (DEN) (200 mg/kg b wt, i.p.) once a week for 2 weeks, followed by treatment with DDT, a tumor promoter (0.05% in diet) for 2 weeks and kept under observation for another 18 weeks, demonstrated the development of malignancy. Pretreatment of Wistar rats with the aqueous extract of the roots of Asparagus racemosus prevented the incidence of hepatocarcinogenesis. Immunohistochemical staining of the hepatic tissues of rats treated with DEN showed the presence of p53+ foci (clusters of cells expressing the mutated p53 protein), whereas an absence of p53+ foci was observed in Wistar rats pretreated with the aqueous extract of the roots of Asparagus racemosus. The microsections of the hepatic tissue of rats treated with DEN followed by treatment with the aqueous extract of Asparagus racemosus showed an absence of p53+ foci. The results of the biochemical determinations also show that pretreatment of Wistar rats with the aqueous extract of Asparagus racemosus leads to the amelioration of oxidative stress and hepatotoxicity brought about by treatment with DEN. These results prove that the aqueous extract of the roots of Asparagus racemosus has the potential to act as an effective formulation to prevent hepatocarcinogenesis induced by treatment with DEN. Copyright (c) 2008 John Wiley & Sons, Ltd.

• Effects of nitric oxide modulators on cardiovascular risk factors in mild hyperhomocysteinaemic rat model.

  Authors: Meenakshi Sharma, Santosh Kr Rai, Rakesh Kr Tiwari, Manisha Tiwari, Ramesh Chandra

  Basic & clinical pharmacology & toxicology. 07/2008; 103(1):25-30.

  Hyperhomocysteinaemia is considered to be an independent risk factor in atherosclerosis. In the present article, we observed the effect of nitric oxide modulators on cardiovascular risk factors inHyperhomocysteinaemia is considered to be an independent risk factor in atherosclerosis. In the present article, we observed the effect of nitric oxide modulators on cardiovascular risk factors in mild hyperhomocysteinaemic rats. A rat model of mild hyperhomocysteinaemia was established by administering methionine (1 g/kg body weight, orally) for 4 weeks. The other groups were concomitantly treated with sodium nitroprusside (SNP) and N(omega)-nitro-l-arginine (LNNA) during the induction of hyperhomocysteinaemia. Lipid profile, total antioxidant capacity and the level of homocysteine and NO(x) (nitrates and nitrites) was examined in serum at 0 and 4 weeks. Activity of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the mRNA level of caveolin, P2 receptors and cardiovascular risk factors were also analysed. Stimulated lipid profile of rats by the treatment of methionine (1 g/kg body weight) reduced significantly by the treatment of SNP with methionine. LNNA increased the level of cholesterol in aorta (P < 0.05 versus group II). SNP significantly suppressed the activity of HMG-CoA reductase. The mRNA levels of caveolin (P < 0.05), P2X (P < 0.05) and P2Y (P < 0.05) showed a significant decrease in rats administered with SNP. LNNA showed significant induction in the expression of caveolin (P < 0.01) and P2Y (P < 0.01) expression. The level of P2X showed no remarkable change in animals treated with LNNA and methionine both. These data conclude that nitric oxide modulators modulate the effect of hyperhomocysteinaemia on the other cardiovascular risk factors and confirm the finding that nitric oxide plays an important role in homocysteine-induced cardiovascular diseases.

• In vivo evaluation of anti-oxidant and anti-lipidimic potential of Annona squamosa aqueous extract in Type 2 diabetic models.

  Authors: Rajesh Kumar Gupta, Achyut Narayan Kesari, Sandhya Diwakar, Ameetabh Tyagi, Vibha Tandon, Ramesh Chandra, Geeta Watal

  Journal of ethnopharmacology. 07/2008; 118(1):21-5.

  AIM OF THE STUDY: Diabetes is known to involve oxidative stress and changes in lipid metabolism. Many secondary plant metabolites have been shown to possess antioxidant activities, improving theAIM OF THE STUDY: Diabetes is known to involve oxidative stress and changes in lipid metabolism. Many secondary plant metabolites have been shown to possess antioxidant activities, improving the effects of oxidative stress due to diabetes. The present study was aimed to evaluate the effect of water extract of Annona squamosa leaves on antioxidant enzymes and lipid profile of animal models of type 2, non-insulin dependent diabetes mellitus (NIDDM). MATERIAL AND METHODS: The plant material was extracted with boiling water for 2 h. Albino Wistar rats (n=24) were divided into four groups. Diabetes was induced by streptozotocin injection (ip) at a dose of 50mg/kg. Animals of treated groups were given the dose of 350mg/kg of the extract. The excised rat tissues were rinsed in ice-cold saline, blotted dry and weighed. RESULTS AND CONCLUSIONS: The results clearly suggest that the water extract of Annona squamosa leaves possessed antioxidant activity as shown by increased activities of scavenging enzymes, catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione reductase (GR) and glutathione-s-transferase (GST) and decrease in malondialdehyde levels present in various tissues. Administration of the extract also improved the lipid profile of the treated groups indicating thereby that the high levels of triglyceride and total cholesterol associated with diabetes can also be significantly managed with the extract.

• Guanidinium-grafted polyethylenimine: an efficient transfecting agent for mammalian cells.

  Authors: Surendra Nimesh, Ramesh Chandra

  European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft für Pharmazeutische Verfahrenstechnik e.V. 04/2008; 68(3):647-55.

  Polyethylenimine (PEI) is one of the most efficient polycationic non-viral gene delivery vectors. Its efficiency and cytotoxicity depends on molecular weight, with the 25-kDa PEI being most efficientPolyethylenimine (PEI) is one of the most efficient polycationic non-viral gene delivery vectors. Its efficiency and cytotoxicity depends on molecular weight, with the 25-kDa PEI being most efficient but accompanied with cytotoxicity. In the present study, enhancement in gene delivery efficiency along with reduction in cytotoxicity by attachment of guanidinium side group was explored. The hypothesis was that the guanidination would lead to the delocalization of charge present on primary amines of the polymer thereby leading to enhancement in gene delivery efficiency along with reduction in cytotoxicity. The polymer was guanidinated using O-methylisourea hemisulfate and the chemical linkage characterized by FTIR spectroscopy. The hydrodynamic diameter of guanidinated PEI-DNA complexes was determined using DLS. Subsequently, these complexes were used for DNA binding assay and zeta-potential measurements, taking native PEI as reference. Further, guanidinated PEI-DNA complexes were investigated for their gene delivery efficacy on HEK 293 cells. The hydrodynamic diameter of guanidinated PEI-DNA complexes was found to be in the range of 176-548 nm. As expected, the zeta potential values increased, on increasing the N/P ratios. It was found that guanidinated PEI had higher transfection efficiency at the majority of the N/P ratios tested as compared to commercially available transfecting agent lipofectin and native PEI itself. The toxicity of guanidinated PEI-DNA complexes was also reduced considerably in comparison to PEI polymer, as determined by MTT colorimetric assay. Out of the various derivatives prepared, gPEI 56% was found to be the most efficient in in vitro transfection.

• Preclinical pharmacokinetics and bioavailability of noscapine, a tubulin-binding anticancer agent.

  Authors: Ritu Aneja, Neerupma Dhiman, Jyoti Idnani, Anshumali Awasthi, Sudershan K Arora, Ramesh Chandra, Harish C Joshi

  Cancer chemotherapy and pharmacology. 12/2007; 60(6):831-9.

  BACKGROUND: Noscapine, a naturally occurring antitussive phthalideisoquinoline alkaloid, is a tubulin-binding agent currently in Phase I/II clinical trials for anticancer therapy. Unlike currentlyBACKGROUND: Noscapine, a naturally occurring antitussive phthalideisoquinoline alkaloid, is a tubulin-binding agent currently in Phase I/II clinical trials for anticancer therapy. Unlike currently available antimitotics such as taxanes and vincas, noscapine is water-soluble, well tolerated, and shows no detectable toxicity. OBJECTIVE: The goal was to develop a simple, sensitive, quantitative, selective, and less time-consuming high-performance liquid chromatography (HPLC) method for determination of noscapine and to study its pharmacokinetics in mice models. METHOD: Noscapine was extracted from mice plasma using the protein-precipitation method and detected using a reversed-phase C8 column with mobile phase consisting of 35% acetonitrile and 65% ammonium acetate buffer (pH 4.5) at 232 nm wavelength. Pharmacokinetic studies of noscapine were performed in mice following intravenous bolus at 10 mg/kg and oral administrations at 75, 150, and 300 mg/kg. RESULTS: The standard curves for noscapine estimation were linear between 390 and 50,000 ng/ml (lower limit of quantification was 390 ng/ml) and the recovery was approximately 80%. Following 10 mg/kg intravenous dose, mean plasma concentrations of 7.88 microg/ml were achieved at 5 min in mice and declined with undetectable levels at 4 h. The mean total body clearance was 4.78 l/h. The mean volume of distribution (V (d)) was 5.05 l. Non-compartmental analysis yielded the mean area under the plasma concentration-time curve (AUC) for noscapine as 53.42, 64.08, and 198.35 h microg/ml reaching maximum plasma concentrations (C (max)) of 12.74, 23.24, and 46.73 microg/ml at a t (max) of 1.12, 1.50, and 0.46 h at the linearly increasing dose levels. CONCLUSION: A rapid and simple HPLC/UV method for the quantification of noscapine in plasma has been developed to study pharmacokinetics of noscapine at tumor-suppressive doses in the mouse. Since orally available anticancer drugs are rare, therefore, noscapine, an innocuous agent, having a mean oral bioavailability of 31.5% over the studied dose range merits its further advancement in humans for anticancer therapy.

• Effect of hyperhomocysteinemia on cardiovascular risk factors and initiation of atherosclerosis in Wistar rats.

  Authors: Meenakshi Sharma, Santosh Kumar Rai, Manisha Tiwari, Ramesh Chandra

  European journal of pharmacology. 12/2007; 574(1):49-60.

  Hyperhomocysteinemia is considered an independent risk factor for atherosclerosis. The present study was designed to assess the effect of high level of serum homocysteine on other cardiovascular riskHyperhomocysteinemia is considered an independent risk factor for atherosclerosis. The present study was designed to assess the effect of high level of serum homocysteine on other cardiovascular risk factors and markers in rats and to study its mode of action in initiating atherosclerosis. To address this issue, four different doses of methionine (0.1 g/kg, 0.25 g/kg, 0.5 g/kg, 1 g/kg) were orally administered to four groups (Group II, III, IV, V respectively) of rats (6 rats in each group) for a period of 8 weeks to get different level of homocysteine in serum. Group I was administered with saline and served as control. Our results revealed that the level of Total cholesterol, Triglyceride, and Oxidized low-density lipoproteins increased significantly with the increase in the level of serum homocysteine. The levels of Resistin, C-reactive protein and cysteinyl-leukotrienes were found to be significantly high in Group IV (P<0.001 vs Group I) and Group V (P<0.001 vs Group I) at 8 weeks. Total antioxidant capacity and nitrite/nitrate level in serum showed negative correlation with the increased dose of methionine. The mRNA expression and the enzyme activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase significantly increased only in livers of rats of Group V. Furthermore, high mRNA expression of P2 receptors and caveolin were found in aorta of rats administered with high dose of methionine (Group IV and V at 8 weeks). Data obtained from in-vitro effect of homocysteine on isolated aortic arch also showed induction in P2 receptors and caveolin with the increase in the concentration of homocysteine. These findings collectively suggest that hyperhomocysteinemia initiates atherosclerosis by modulating the cholesterol biosynthesis and by significantly inducing the level of other cardiovascular risk factors and markers, which play important role in initiating atherosclerosis.

• Preliminary studies on antihyperglycemic effect of aqueous extract of Brassica nigra (L.) Koch in streptozotocin induced diabetic rats.

  Authors: Prachi Anand, K Y Murali, Vibha Tandon, Ramesh Chandra, P S Murthy

  Indian journal of experimental biology. 09/2007; 45(8):696-701.

  In the streptozotocin induced diabetic rats treated separately with aqueous, ethanol, acetone and chloroform extracts of the seeds of B. nigra, the increase in serum glucose value between 0 and 1 hrIn the streptozotocin induced diabetic rats treated separately with aqueous, ethanol, acetone and chloroform extracts of the seeds of B. nigra, the increase in serum glucose value between 0 and 1 hr of glucose tolerance test (GTT) was the least (29 mg/dl) in aqueous extract treated animals while it was 54, 44 and 44 mg/dl with chloroform, acetone and ethanol extracts respectively. In further studies carried out with aqueous extract, the effective dose was found to be 200 mg/kg body weight in GTT. Administration of 200 mg/kg body weight of aqueous extract to diabetic animals daily once for one month brought down fasting serum glucose (FSG) levels while in the untreated group FSG remained at a higher value. In the treated animals the increase in glycosylated hemoglobin (HbA1c) and serum lipids was much less when compared with the levels in untreated diabetic controls. These findings suggest that further studies with the aqueous extract of B. nigra seeds on its antidiabetic activity would be useful.