Iranian Journal of Pharmaceutical Sciences

In this study, microspheres containing estradiol valerate were prepared by solvent evaporation method using poly (glycolide-co-lactide) (PLGA 50:50) and poly
(lactide). The effect of different process variables such as polymer type, drugpolymer ratio, stirring rate, volume of internal phase and temperature of external
phase on the morphology, particle size distribution, encapsulation efficiency and in vitro release profile were investigated. All microspheres had spherical shape with smooth surface. Increasing the internal phase volume and decreasing the external phase temperature resulted in smaller particles. At low drug loadings, PLGA microspheres were larger than PLA ones. Changing the theoretical drug loading from 5 to 20% decreased the drug release rate from PLGA microspheres whereas the result for PLA microspheres was the opposite.

Furin is a Ca2+ -dependent serine protease which cleaves proprotein substrates at the Arg-Xaa-(Lys/Arg)-Arg site to generate biologically active proteins. Furin’s
critical role in many cellular events associated with health disorders such as HIV, SARS, anthrax, and influenza as well as cancer has made inhibitors of this enzyme as therapeutic targets. To this date, the most potent inhibitor of furin is the bioengineered serpin (serine protease inhibitors) protein namely α1-PDX. It was already demonstrated that the reactive site loop (RSL) of all serpins are prime interactive domains responsible for their protease inhibitory function. Therefore, the objective of the present study was to develop small peptides with the RSL structure of serpin α1-PDX, as inhibitors of furin activity. Fifteen peptides were designed from reactive site loop structure of α1-PDX (sequences 367-394) with different mutations in this site, and were synthesized using a solid-phase peptide synthesizer, and characterized by MALDI-tof mass spectrometry and amino acid analysis. The inhibitory effects of the designed peptides against furin activity were evaluated by spectroflourometry using QVEGF-C [Abz-QVHSIIRRßSLP-Y(NO2)-A-CONH2, Abz = 2-amino benzoic acid and Y(NO2) = 3-nitro tyrosine] as substrate. The results showed that all of the designed peptides inhibit furin activity with different efficacies in a time and concentration dependent pattern. Peptides containing His or straight alkyl side chain amino acids in positions P2, P3, P6 and P8 have higher efficacy for blocking furin activity in comparison with peptides containing Arg or Lys in that position. The study further revealed that the peptides inactivate furin in a slow tight binding pattern. Our study provides an alternate strategy for development of efficient peptide-based inhibitors of proprotein convertases such as furin.

Extracellular Ca2+ concentration ([Ca2+]o) may be one of the factors affecting atrial natriuretic factor (ANF) release. In the previous studies, there are opposite reports about the effect of [Ca2+]o on ANF secretion. Therefore, the effect of [Ca2+]o depletion on ANF secretion and gene expression was studied in the present research. Isolated right atria from rats were perfused for 6 and 2 hours in the presence and absence of [Ca2+]o, and ANF secretion were measured using radioimmunoassay method. Cyclohexamide was used in another group as a protein synthesis inhibitor. ANF mRNA level in atria measured by Real time PCR. [Ca2+]o depletion induced a significant increase in basal ANF release. This stimulatory effect peaked at 2 h, then started to decrease and reached around basal levels by 6 h. Protein synthesis inhibition by cyclohexamide did not abolish or significantly decrease the stimulatory effect of Ca2+-free media on ANF secretion. The ANF gene expression was not significantly affected by Ca2+-free media. These results suggest that the contractile and endocrine function of atrial cardiocytes are differently affected by [Ca2+]o and may represent an adaptation to the dual roles of the atrial myocytes contraction and secretion.

Lipases catalyze hydrolysis and synthesis of triacylglycerols. These enzymes, especially the microbial ones, have wide commercial and industrial usage. Bacillus subtilis lipase has interesting properties such as small size and tolerance to basic pH; therefore, developing techniques for its recognition and isolation is the focus of research in many laboratories. In the present study, two factors i.e. MgCl2 concentration and annealing temperature were manipulated for the optimization of the polymerase chain reaction (PCR) condition. As for the MgCl2 concentration, 2.5 mM produced the best results when the annealing temperature was kept at 55 oC. Regarding the annealing temperatures, the best amplification was obtained at 63.9 ^oC. It can be concluded that the PCR conditions for the detection of lipase gene in Bacillus subtilis has been optimized and can be used for the screening and isolation of these bacaterial strains.

Hydroxypyridinone iron chelators are currently the main candidates for development of orally active iron chelating alternatives to desferrioxamine (DFO). In the present study, the relative efficacy and liver toxicity of a bidentate chelator, 2-methyl-3-hydroxypyridin-4-one (MHPO), was studied in iron overloaded rats and compared with those of DFO. For iron overloading, rats received i.p. injections of 100 mg/kg of iron-dextran twice a week for 4 consecutive weeks. They were
allowed for equilibration of iron after overloading for 15 days. Then the rats received i.p. injections of 200 mg/kg/day of either MHPO or DFO for 15 days. At the end of this period, blood samples were taken and the iron and ferritin concentrations, and the total iron binding capacity (TIBC) were determined. The activities of SGOT, SGPT and ALP were analyzed by standard colorimetric kits. Serum values for iron, TIBC and ferritin were shown to have no significant differences after the administration of either MHPO or DFO in treated rats. SGOT and SGPT values were significantly reduced after the administration of MHPO. DFO, however, was only able to reduce SGPT with the same dose. There were no significant differences between two chelators with regards to ALP. After the administration of MHPO, skin rashes were observed in a way that rats could not move. In conclusion, this study confirms that MHPO is at least as effectives as DFO at mobilizing iron, and reduces liver toxicity, however, with regard to other side effects such as its skin toxicity, further studies are required.

The effect of aqueous extract of Nepata glomerulosa Boiss. aerial parts on morphine withdrawal syndrome was investigated in mice. Dependence was induced by subcutaneous injections of morphine for 3 consecutive days. On day 4, morphine was injected 2 h prior to intraperitoneal injection of naloxone. The number of jumps during a 20 min. period after naloxone injection was considered as a measure of the withdrawal syndrome. Open field and rotarod tests were also performed. The results indicated that the aqueous extract (0.1 to 2.8 g/kg, s.c.) and diazepam (5 mg/kg) reduced the number of jumps (58±2.3 to 10±0.82, p<0.001 vs normal saline, 87±3.4). The extracts also reduced motion balance and locomotion activity. It is concluded that the aqueous extract of N. glomerulosa aerial parts could diminish morphine withdrawal syndrome.

Aprocedure was developed for rapid in vitro germination of Linum album seeds by scarification and exposing to gibberellic acid (GA3) and kinetin (Kn). Concentrations of podophyllotoxin (PTOX) and related aryltetralin lignans α-peltatin, β-peltatin, 5’-demethoxy-6-methoxypodophyllotoxin and 6-methoxypodophyllotoxin (MPTOX) in L. album fresh plant organs were determined by HPLC. A degree of variation was observed in lignan content in different plant parts and growth stages. It was found that PTOX is predominant in productive organs and leaves. The highest amount of PTOX (0.651 mg/100g dry wt.) and MPTOX (0.670 mg/100g dry wt.) and the total quantified lignans were found in the capsules. In vitro cultures were studied for lignans followed by high productive cell line selection. Calli cultures were more productive for MPTOX than PTOX, while suspension cells accumulate comparable amounts of PTOX and MPTOX. The highest amount of PTOX (0.301% mg/g dry wt.) was found in suspension originated immobilized cultures.

The volatile oil obtained by hydrodistillation of the aerial parts of Matricaria chamomilla L. (Asteraceae) growing in Botanical Garden, Isfahan University of Medical Sciences, Iran, was investigated by gas chromatography (GC) and GC/ mass spectrometery (MS). Sixty-three components were characterized, representing 86.21% of the total oil components detected. α-Bisabolol oxide A(25.01%) and abisabolol oxide B (9.43%) were the major constituents of the oil.