Pharmaceutical Sciences
Volume:15 Issue: 4, 2010

Hypercholesterolemia is the main risk factors for atherosclerosis and atherosclerosis is the major cause of heart diseases and stroke. In the present study، we investigated the effect of total extract of Securigera securidaca L. seeds on the serum lipid profile and oxidative stresses caused by hypercholesterolemia. Male Wistar rats randomly divided into 6 groups of 6 animals in each. The rats in normal control group were fed a standard laboratory diet and the other groups were fed a high fat diet for 36 days. Oral treatment with the extract started at day of 16 and continued for last 20 days of the experiment period. At the end of the experiment، portal vein blood and liver were collected to measure the lipid levels and other biochemical factors. The results of this study indicated that short-term treatment by hydroalcoholic extract of S. securidaca L. seeds، produced a significant reduction (p<0. 05) in the level of triglyceride، as well as LDL. Compared to acid ascorbic the extract had a weak antioxidant activity in vitro with no effect on total serum anti-oxidant and serum paraoxonase activity. However، the present results showed that high-fat diet induced elevation of malondialdehyde (MDA) level، both in serum and liver، was suppressed markedly by the extract (p<0. 001). The results of this study indicated that the extract of S. securidaca’s seeds in addition to having considerable hypolipidemic effects in high fat fed rats، was able to decrease lipid peroxidation independent of antioxidant activity.

Nanotechnology will affect human being life impressively over the next decade in different fields, including medicine and pharmacy. Polymeric nanoparticles have been far and wide studied as particulate carriers in the pharmaceutical and medical fields since they show promise as drug delivery systems on account of their controlled and sustained- release properties, sub cellular size, biocompatibility with tissue and cells and enhancing the effectiveness of the loaded drugs. Numerous methods have been developed during the last two decades to formulate the pharmaceutical nanoparticles. These methods have been classified according to whether the particle formation implies a polymerization reaction or arises from a macromolecule or preformed polymer. In the current review the most important methods of preparation are explicated, more than ever those that make use of preformed synthetic polymers. Furthermore, the methods which can be commercialized as well as pharmaceutical aspects are discussed briefly. Pharmaceutical nanoparticles can be prepared using different methods depending on the physicochemical properties of the drug and polymers.

Salvia sahendica as an endemic species of salvia in Sahand-Azerbaijan has been used traditionally for treatment of bacterial, fungi and Dyspepsia diseases. The aim of this study was to investigate the antioxidant activity of various S. sahendica extracts and evaluate the effect of main extract with high antioxidant properties on enzyme and non-enzymatic antioxidant factors in oxidative stress induced by ethanol in rat albino wistar. in this study the antioxidant activity of various extracts of Salvia sahendica was evaluated using 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging assay and then the protective effect of potential extract (with high antioxidant activity) on rat albino weighting 150-200 g which administered orally ethanol for one month was evaluated. Measurement antioxidant activity by scavenging of DPPH radical showed that methanol extract of S. sahendica possesses the highest antioxidant activity (IC50= 17.14 μg/ml). Treatment alcohol rats with S. sahendica methanol extract at a dose of (0.1 g/kg body weight) significantly reduced the level of lipid peroxidation and liver marker enzymes and restored the enzymic and non-enzymatic antioxidants levels in liver and kidney of treated rats. The results of this study strongly indicate that S. sahendica methanol has potent hepatoprotective effect against alcohol induced tissues damage in experimental animals due to its radical scavenging activity. In order to find the function mechanism of this plant and phyotochemical properties, further investigations should be done.

Drug delivery of impermeable drugs through biological membrane is currently one of the major interests in pharmaceutical research. It has been shown that there are different absorption enhancers which can provide rapid absorption in the gastrointestinal tract. The aim of the present project is determining of intestinal absorption of furosemide, an anionic drug, in the prescence of sodium carboxy methyl cellulose (NaCMC), an anionic macromolecule. Methylcellulose is used as a chargeless macromolecule to show the influence of polymer viscosity in dialysis process. The polymers were used at the concentrations of ((NaCMC: 0.5%, 2%, 3%, 6%, 8%), (MC: 0.5, 4%, 8% w/v%)) and drug concentration in all cases were 12.5 μg/ml. The whole process was performed in a receptor chamber in which a dialysis bag was placed as a donor medium. The temperature was kept in 37 °C and samples were collected at different time points up to 4 hours. Finally the samples were analyzed by ultraviolate spectrophotometery at 277.5 nm. Obtained data indicated that the dialysis rate increased by increasing the NaCMC amount up to a certain concentration. This could be explained by donnan equilibrium. Poly electrolytes (like NaCMC) enhance the transport rate of ionic drugs with same electrical charge. However the increased medium viscosity in the dialysis process would limit the donnan effect. The result showed that anionic polymers could be used as absorption enhancers for anionic drugs like frusemide in specific concentrations.

The purpose of this study is preparation and evaluation of enteric release piroxicam microparticles having soild dispersion structure in presence of Eudragit S100 to improve the dissolution rate and reduce the local gastrointestinal irritation of piroxicam. Microparticles were prepared by spherical crystallization method with different ratio of drug, Eudragit S100 (enteric polymer) and Aerosil as an antiadhesion agent. The micromeritic properties such as particle size, shape and flowability were investigated and in vitro release characteristics of microparticles were evaluated. The physical state of piroxicam in microparticles was analysed using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffractometry. The stability of microspheres was also evaluated in a 3-month accelerating condition stability. The results showed that spherical and uniform microparticles were obtained with high encapsulation efficiency (>90%) and improved micromeritics properties. The physical state investigations indicated that crystalline form of piroxicam in microparticles was disordered, suggesting that piroxicam was highly dispersed in microparticles as amorphous state. Also microparticles were stable after 3 mounth storage in accelerating conditions. Drug release studies showed that piroxicam in microparticles was well protected in an acidic medium and increased dissolution rate in basic medium from the polymeric solid molecular dispersion as compared with the crystalline pure drug. Thus, present study demonstrated the high potential of spherical crystallization technique for obtaining stable microparticles of poorly water soluble drugs using enteric polymers carriers.

Floating drug delivery system is one of the novel methods in drug delivery. This study evaluates the relationship and influence of formulation factors such as polymer type, drug: polymer ratio and gas forming agents on drug release and floating properties of matrices containing HPMC Kl00M and carbopol 974P and indomethacin as a model drug. In the present study attempt was made to form Indomethacin floating formulations using HPMC kl00M, carbopol 974P, lactose and floating agents in different ratios. Tablets were prepared by direct compression method. The physicochemical properties of tablets prepared were investigated. Rate of drug release was studied using USP II at pH 1.2 and 7.2. For study the release kinetics of indomethacin from the matrix tablets, the release data were fitted to the zero order, first order, higuchi and pepas equations. The results showed that all the polymers used in this study could slow down the release of indomethacin from the matrices prepared. Addition of gas generating agent to the formulation containing HPMC alone can modify the floating properties of related matrices. Incorporation of carbopol was found to compromise the floating capacity of related formulations due to the difference in the basic properties of HPMC and Carbopol in water uptake potential. Results showed that the effect of combination of polymers and floating agents on drug release and its kinetic. The use of HPMC K100M and lactose in 1:1 ratio and incorporation of 5% of floating agents can lead to suitable floating formulation of indomethacin.

Interleukin-11 (IL-11) is a thrombopoietic growth factor that stimulates the proliferation of hematopoietic stem cells and megakaryocytes and induces megakaryocyte maturation resulting in increased platelet production. IL-11 has recently been approved for treatment of chemotherapy induced thrombocytopenia in cancer patients. This cytokine is the first growth factor that gained FDA approval for this application. The aim of this study was cloning and recombinant expression of human IL-11 in E. coli. RNA was extracted from a human bone marrow sample and used for cDNA synthesis. cDNA was applied for amplification of IL-11 gene by PCR. The PCR product was cloned, sequenced and expressed in E. coli using pET28a expression vector. Amplification of human IL-11 gene using primers designed on mature full length coding region of IL-11 resulted in a 531 bp fragment as visualized by agarose gel electrophoresis. Sequencing of the cloned fragment confirmed the identity of sequence of cloned gene. Expression by pET28a vector resulted in a high level production of recombinant IL-11 which appeared as a 24 kDa protein in the SDS-PAGE analysis of induced culture. The result of the present study indicated that the E. coli expression system is a suitable expression system for recombinant expression of human IL-11 and could be used for mass production of this cytokine due to high-density cell growth and fast product formation.

Although liquisolid formulations can show a fast dissolution rate, loading factor is not very high due to lack of good flowability and compactibility. Therefore, the aim of the present study was to improve flow, compactibility and dissolution of piroxicam liquisolid formulations by incorporating different types of microcrystalline cellulose. Several formulations were prepared and their physico-mechanical and dissolution behaviors were investigated. In the present study, propylene glycol, silica and sodium starch glycolate were used as non-volatile solvent, coating material and disintegranting agent respectively. Physical stability of the liquisolid formulations was also investigated to see the effect of aging on hardness and dissolution. Comparing all hardness data showed that liquisolid compacts containing avicel PH101 and 200 showed superior compactibility than those formulations containing avicel 102. Although avicel PH 200 on its own had better flowability than other grades, in liquisolid formulations avicel PH 101 showed better performance than other grades in terms of flowability. The results showed that a better dissolution rate was obtained with liquisolid formulations containing avicel PH 101 and 102 compared to the formulations containing avicel PH 200. The results showed these liquisolid formulations were stable under the stored conditions and hardness and dissolution behaviours of liquisolid formulations were not significantly affected by aging. It could be concluded that by choosing the right type of carrier flow and hardness of liquisolid formulations can be improved without any significant negative effect on dissolution performance of piroxicam liquisolid compacts.