DARU, Journal of Pharmaceutical Sciences
Volume:19 Issue: 4, 2011

Background and the purpose of the study:Olanzapine is an antipsychotic used in treatment of schizophrenia. This research was carried out to design oral controlled release matrix pellets of water insoluble drug Olanzapine (OZ), using blend of Sodium Alginate (SA) and Glyceryl Palmito-Stearate (GPS) as matrix polymers, micro crystalline cellulose (MCC) as spheronizer enhancer and Sodium Lauryl Sulphate (SLS) as pore forming agent.Olanzapine is an antipsychotic used in treatment of schizophrenia. This research was carried out to design oral controlled release matrix pellets of water insoluble drug Olanzapine (OZ), using blend of Sodium Alginate (SA) and Glyceryl Palmito-Stearate (GPS) as matrix polymers, micro crystalline cellulose (MCC) as spheronizer enhancer and Sodium Lauryl Sulphate (SLS) as pore forming agent. OZ formulations were developed by the pelletization technique by drug loaded pellets and characterized with regard to the drug content, size distribution, Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction study (XRD). Stability studies were carried out on the optimized formulation for a period of 90 days at 40 ± 2 °C and 75 ± 5% relative humidity.Results and major The drug content was in the range of 93.34-98.12 %. The mean particle size of the drug loaded pellets was in the range 1024 to 1087μm. SEM photographs and calculated sphericity factor confirmed that the prepared formulations were spherical in nature. The compatibility between drug and polymers in the drug loaded pellets was confirmed by DSC and FTIR studies. Stability studies indicated that pellets are stable. XRD patterns revealed the crystalline nature of the pure OZ. Loose surface crystal study indicated that crystalline OZ is present in all formulations and more clear in formulation F5. Drug release was controlled for more than 24 hrs and mechanism of the drug release followed by Fickian diffusion. It may be concluded that F5 is an ideal formulation for once a day administration.

Background and the purpose of the study:Studies show that chitosan nanoparticles increase mucoadhesivity and penetration of large molecules across mucosal surface. The aim of the present study was to investigate the use of thiolated chitosan in the development of polysaccharide-coated nanoparticles in order to confer specific functionality to the system.Methyl methacrylate nanoparticles were coated with thiolated chitosan using a radical polymerization method. Thiolation was carried out using glutathione (GSH) to improve mucoadhesivity and permeation enhancing properties of chitosan. Mucoadhesion studies were carried out by calculating the amount of mucin adsorbed on nanoparticles in a specific period of time. Complement consumption was assessed in human serum (HS) by measurement of the hemolytic capacity of the complement system after contact with nanoparticles. The FT-IR and 1HNMR spectra both confirmed the synthesis and showed the conjugation of thiolated chitosan to methyl methacrylate (MMA) homopolymer. Nanoparticles were spherical having a mean diameter within the range of about 334-650 nm and their positive zeta potential values indicated the presence of the cationic polysaccharide at the nanoparticle surface. Increasing the amount of thiolated chitosan led to mucoadhesivity and complement activation. However there was not dose dependent correlation between these phenomenons and the absence of thiolated chitosan led to particles with larger size, and without ability to activate complement process. Major It can be concluded that nanoparticles could be used for the mucosal delivery of peptides and proteins. Results show that the thiolated chitosan had higher mucoadhesion and complement activation than unmodified chitosan.

Background and the Purpose of the study:Many drug substances and variety of naturally occurring dietary or herbal components are capable of interaction with the CYP enzyme system. The aim of the study was to investigate the effect of pomegranate juice pretreatment on the bioavailability of buspirone in rabbits.White New Zealand rabbits weighing 2.1±0.13 Kg were selected for study. The bioavailability of buspirone after pre-treatment with pomegranate juice (10 ml Kg-1 for seven days) was compared with an oral solution of 10 mg kg-1 of buspirone in distilled water. Animals were allowed free access to food and water, until night prior to dosing and were fasted for 10 hrs. In the first phase oral solution (10 mg kg-1) was administered through feeding tube followed by rinsing with 10 ml of water. In the second phase, the group was pretreated with pomegranate juice for 7 days and study was conducted after 15 days of washout period.Results and The results showed that there was a significant (p<0.05) difference in the bioavailability of buspirone after pre-treatment with pomegranate juice.This increase in bioavailability might be due to inhibition of CYP3A4. Further studies are required to prove this mechanism in humans.

Background and the purpose of the study:Different methods have been proposed to modify glassy carbon electrode in order to determine dopamine (DA), as one of the most important neurotransmitters in central nervous systems of mammalian. These methods are time comsuming and in some cases expensive. In this work, a very simple and cheap pretreatment method is developed for the bare glassy carbon electrode (GCE) to determine DA in the presence of Ascorbic acid (AA).Cyclic voltammetry as an electrochemical activation procedure was used for activation of glassy carbon electrode in order to separate diffrential pulse peaks of DA and AA. The effect of different parameters such as pH for supporting electrolyte, range of potential and the number of cycles were investigated. Finally, differential pulse voltammetry was used to determine DA in the presence of AA.On the activated electrode under optimum condition, anodic peak of AA shifted to negative potentials and peak current decreased, but the peak current of DA increased. The peak current was linearly proportional to the bulk concentration of DA in the range of 6.5×10-7- 1.8×10-5 mol l-1. The limit of detection was 6.2×10-7 mol l-1.A simple and cheap method was developed for the activation of glassy carbon electrode. It was possible to determine DA in the presence of AA on the treated electrode. The proposed method was used to determine DA in pharmacutical samples.

Background and the purpose of the study:Several plant essential oils, as well as terpenes present in essential oils, have shown gastroprotective activity. The aim of the present work was to evaluate the gastroprotective activity of α-terpineol, a monoterpene alcohol which is present in essential oils of various plants.The gastroprotective activity of α-terpineol was evaluated in rats by assessing the changes in ethanol and indomethacin-induced gastric ulcer scores and on gastric secretory volume and total acidity in pylorus-ligated rats. Alpha-terpineol was administrated orally at the doses of 10, 30, and 50 mg/kg one hour before administration of the ulcer inducing agents by the pylorus ligation procedure. The involvement of endogenous prostaglandins in the protective effect of α-terpineol in ethanol-induced gastric lesions test was assessed by administration of indomethacin (10 mg/kg, s.c.) 30 min before oral administration of α-terpineol at the dose of 50 mg/kg.α-terpineol presented gastroprotective activity against ethanol-induced ulcers at the doses of 10, 30, and 50 mg/kg. Epoxy-carvone at the dose of 10 mg/kg did not present gastroprotective activity against ulcer induced by indomethacin, but at the doses of 30 and 50 mg/kg it attenuated the gastric damages induced by this agent significantly. Pretreatment with indomethacin did not prevent the gastroprotective effect of α-terpineol on ethanol-induced ulcers. Alpha-terpineol also did not affect the gastric secretion in pylorus-ligated rats.Major The results suggest that α-terpineol presents gastroprotective action which does not involve either an increase in the synthesis of endogenous prostaglandin or a decrease in the gastric acid secretion.

Background and the purpose of the study: Thymoquinone (TQ) is one of the active components of Nigella sativa. The plant has been used in herbal medicine for treatment of many diseases including liver complications. The present study aimed to investigate protective effects of TQ on Aflatoxin B1 (AFB1) induced liver toxicity in mice. Animals were divided into six groups and treated intraperitoneally. Group 1 (blank) served as vehicle, group 2 (positive control) received AFB1, Group 3 was treated with 9 mg/kg of TQ, Groups 4, 5 and 6 were treated with 4.5, 9 and 18 mg/kg of TQ, respectively. After three consecutive days, except for groups 1 and 3, animals were administered with a single dose of AFB1 (2 mg/kg). All the animals were killed 24 hrs following the AFB1 administration under ether anesthesia. Biochemical parameters including AST, ALT and ALP in serum samples and glutathione (GSH) and malondialdehyde (MDA) contents in liver homogenates were determined. Liver sections were collected for histopathological examination. Findings of this study showed that AST, ALT, ALP and MDA levels were significantly lower in the TQ treated animals as compared to AFB1 group (group 2). Furthermore, TQ was able to recover glutathione content (GSH) of liver tissue. The best response, however, was observed with the dose of 9 mg/kg. Liver sections of AFB1 intoxicated mice showed inflammation, necrosis, hyperplasia of kupffer and infiltration of mononuclear cells, dilation of sinusoids and disruption of hepatocytes, while treatment with TQ helped to normalize liver architecture in accordance to biochemical findings. Taken collectively, TQ has a protective role with optimum dose of 9 mg/kg in AFB1 hepatotoxicity.

Background and the purpose of the Study: Extract of Boswellia Serrata species has been used in the Indian traditional medicine in the treatment of various inflammatory diseases. The present study was designed to evaluate anti-inflammatory effects of Frankincense in the treatment of gingivitis, which is a periodontal tissue inflammatory disease. This double blind randomized placebo controlled trial was carried out among high school female students with moderate plaque-induced gingivitis. Based on either administration of 0.1 gram of Frankincense extract or 0.2 gram of its powder or placebo and whether the patients undergone scaling and root planning (SRP) or not, they were randomly assigned to 6 groups. The primary efficacy outcome was changes in Gingival Index (Loe & Sillness) and the secondary outcomes were alteration in plaque index (Sillness & Loe), bleeding index (Cowell) and probing pocket depth (WHO probe). All indices were measured in the 0, 7th and 14th days of the study. Seventy five patients ranged of 15-18 years old were enrolled. At the end of the study, the indices in all groups showed significant decreases in comparison to the first day (p< 0.05), except for the bleeding index in the group without SRP and drug therapy (p=0.111). More precise analysis of data revealed that SRP in association with Frankincense application (either extract or powder) can lead to remarkable decrease in inflammatory indices in comparison to the groups without SRP and drug therapy (p<0.001). In addition, no significant difference was observed between powder or extract therapy (p >0.05) and between patients received either SRP or treatment alone (p=0.169). Frankincense, a safe and low-cost herbal medicine, may be feasibly applied to improve inflammation based disease of gingival as an adjunct to the conventional mechanical therapy.

Background and the purpose of the study: It has been shown that Nigella sativa L. and Portulaca oleracea L. have many antioxidant components. In the present study, the cytoprotective effect of ethanolic and aqueous extracts of N.sativa and P.oleracea against hemolytic damages induced by free radical initiator, AAPH [2, 2' azobis (2- amidinopropane) hydrochloride] was evaluated. Hemolysis was induced by addition of AAPH. To study the cytoprotective effect, aqueous (50, 200, 300, 400, 800 μg/ml) and ethanolic (25, 100, 150, 200 and 400 μg/ml) extracts of N. sativa and aqueous (25, 50, 100, 150, 200 and 400 μg/ml) and ethanolic (300, 600, 900, 1200 and 1800 μg/ml) extracts of P. oleracea were employed. RBCs were incubated with both extracts and AAPH at 37 °C for 6 hrs. In order to evaluate the impact of the time of addition, extracts were added one and 2 hrs after AAPH. Samples of suspensions were removed at different times and the degree of hemolysis was assessed spectrophotometrically by reading the absorption of supernatants at 540 nm. Aqueous (300, 400 and 800 μg/ml) and ethanolic (150, 200 and 400 μg/ml) extracts of N.sativa and also, aqueous (100, 150, 200 and 400 μg/ml) and ethanolic (1200, 1800 μg/ml) extracts of P.oleracea showed concentration-dependent cytoprotective effects. Addition of extracts one hour after AAPH reduced but did not eliminate protective activities of extracts. Cytorotective effect of aqueous and ethanolic extracts of N. sativa and P. oleracea against AAPH- induced hemolysis may be related to antioxidant properties of these plants.

Background and purpose of the study: Fabaceae is the third largest family of flowering plants. Lack of essential oils in the plants of this family can be an advantage in search for safe and effective medicines. In this study the anticonvulsant effect of the leaves of Albizzia julibrissin, Acacia juliflora, Acacia nubica and aerial parts of Astragalus obtusifolius was evaluated in pentylenetetrazole (PTZ) and maximal electroshock (MES) seizure tests. The hydroalcoholic extracts of the plants were obtained by percolation. Different doses of the extracts were injected to the mice intraperitoneally (i.p.) and occurrence of clonic seizures induced by PTZ (60 mg/kg, i.p.) or tonic seizures induced by MES (50 mA, 50Hz, 1sec) were monitored up to 30 min after administration. Acute toxicity of the extracts was also assessed. The safe and effective extract was then fractionated by dichloromethane and anticonvulsant activity of the fractions was determined. Finally, the constituents of the extract and the fractions were screened by thin layer chromatography. Among the extracts, only A. obtusifolius extract showed low toxicity and protective effect against clonic seizures with ED50 value of 3.97 g/kg. Fractionation of the extract led to increase in anticonvulsant activity and ED50 value of 2.86 g/kg was obtained for the aqueous fraction. Phytochemical screening revealed the presence of alkaloids, flavonoids, anthrones and saponins in the aqueous fraction.Major The presence of anticonvulsant compounds in A. obtusifolius suggests further activity-guided fractionation and analytical studies to find out the potential of this plant as a source of anticonvulsant agent.

Background and the purpose of the study: Pentoxifylline (PTX) is a non-specific cytokine inhibitor that has been reported to attenuate pain in several animal models and humans. However, long-term therapeutic effects of PTX on neuropathic pain in a rat model of chronic constriction injury (CCI) are not completely clear. This study was conducted to examine the effect of long-term administration of PTX on neuropathic pain in rats. Neuropathic pain was induced by sciatic nerve ligation using of CCI model in rats. Rats were randomly assigned into sham, CCI-saline treated, and CCI-PTX treated (30 or 60 mg/kg ip) groups. PTX or saline administered at 30 min before CCI and daily for 14 days post-CCI. At the days of 3, 7, 11 and 14 following CCI, by using standard methods effects of thermal hyperalgesia, thermal and mechanical allodynia in all groups were examined using the standard methods. The CCI-saline treated group showed a significant increase in mechanical and thermal allodynia, and thermal hyperalgesia as compared with the sham group in the tested days. Administration of the higher dose of PTX (60 mg/kg/day), but not the lower dose (30 mg/kg/day) significantly reduced mechanical and thermal allodynia, as compared with the CCI-saline treated group on days of 3, 7, 11 and 14 (all P values<0.001). Also, both doses of PTX significantly reduced thermal hyperalgesia as compared with the CCI-saline treated group on these days (all P values<0.001). Results of this study show that chronic administration of PTX reduces the neuropathic pain in a rat model of CCI. Thus, this drug may have a therapeutic application in the treatment and management of neuropathic pain in humans.