Iranian Journal of Basic Medical Sciences
Volume:14 Issue: 1, Jan-Feb 2011

Objective(s)Opioid abuse is still remained a major mental health problem, a criminal legal issue and may cause ischemic brain changes including stroke and brain edema. In the present study, we investigated whether spontaneously withdrawal syndrome might affect stroke outcomes.Materials and MethodsAddiction was induced by progressive incremental doses of morphine over 7 days. Behavioral signs of withdrawal were observed 24, 48 and 72 hr after morphine deprivation and total withdrawal score was determined. Cerebral ischemia was induced 18-22 hr after the last morphine injection by placing a natural clot into the middle cerebral artery (MCA). Neurological deficits were evaluated at 2, 24 and 48 hr after ischemia induction, and infarct size and brain edema were determined at 48 hr after stroke.ResultsMorphine withdrawal animals showed a significant increase in total withdrawal score and decrease of weight gain during the 72 hr after the last morphine injection. Compared to the addicted and control animals, infarct volume and brain edema were significantly increased in the morphine deprived animals (P< 0.05) at 48 hr after cerebral ischemia. Also, neurological deficits were higher in the morphine-withdrawn rats at 48 hr after stroke (P< 0.05). ConclusionOur data indicates that spontaneous withdrawal syndrome may worsen stroke outcomes. Further investigations are necessary to elucidate mechanisms of opiate withdrawal syndrome on stroke.

Objective(s)This study was aimed to assess the possible laxative and prokinetic effects of the boiled extract of Rosadamascena.Materials and MethodsRats in two groups (n= 7) of test and control were gavaged either with the extract or placebo, respectively. The number, weight and water percentage of feces were studied up to 24 hr. In order to assess the possible osmotic laxative effects of the drug, the jejunum in anesthetized rats (n= 7) was randomly divided into 4 cm segments and 0.5 ml of the extract, lactulose or saline was injected in each segment. The volumes of the contents in each segment were measured after 1 hr. In order to assess the intestinal transit time, fasting rats were gavaged with either the extract or placebo. Thirty minutes following the last medication, all rats were gavaged with phenol red and methyl cellulose (1.5 ml). The test and the control rats, in groups of 4, were sacrificed at 30 min, 1, 2 and 4 hr, and the amounts of the phenol red in various parts of the gastrointestinal tract were measured. Results Boiled extract of R. damascena significantly increased feces number and its percentage of water, but had no effects on the transit time of intestinal ingesta. The volume of the contents in jejunum segments had significantly increased with the extract or lactulose compared to placebo. Conclusion Boiled extract of R. damascena apparently exerts its laxative effects, at least in part, via osmotic infiltration of fluids into the intestine.

Objective (s) Porin is a mitochondrial outer membrane channel, which usually functions as the pathway for the movement of various substances in and out of the mitochondria and is considered to be a component of the permeability transition (PT) pore complex that plays a role in the PT. We addressed the hypothesis that porin interacts with other mitochondrial proteins after ischemic injury.Materials and MethodsFor this purpose, we used in vivo 4-vessel occlusion model of rat brain and porin purification method by hydroxyapatite column. After SDS gel electrophoresis and silver nitrate staining, Western blotting was done for porin, adenine nucleotide translocase and cyclophilin-D proteins.Results Porin was purified from mitochondrial mixture in ischemic brain and control groups. Investigation of interaction of adenine nucleotide transposes (ANT) and cyclophilin-D with porin by Western blotting showed no proteins co-purified with porin from injured tissues.Conclusion The present study implies that there may not be interaction between porin, and ANT or cyclophilin-D, and if there is any, it is not maintained during the purification procedure.

Objective(s)Some investigation has indicated that adipose-derived stem cells possess different surface epitopes and differentiation potential according to the localization of fat pad from which the cells were derived. In the present study proliferation capacity and aging of such cells were explored.Materials and MethodsAdherent cells were isolated from the collagenase digests of adipose tissues excised from rat epicardial and epididymal regions and propagated with several subcultures. The cells were then investigated whether or not they were able to differentiate into bone, cartilage and adipose cell lineages. Studied cells from two adipose tissues were also compared with respect to their in vitro proliferation capacity. The presence of senescent cells in the culture was determined and compared using senescence-associated (SA) ß-galactosidase staining method. ResultsSuccessful differentiations of the cells were indicative of their mesenchymal stem cells (MSCs) identity. Epicardial adipose-derived cells tended to have a short population doubling time (45±9.6 hr) than the epididymal adipose-derived stem cells (69±16 hr, P< 0.05). Colonogenic activity and the growth curve characteristics were all better in the culture of stem cells derived from epicardial compared to epididymal adipose tissue. Comparatively more percentage of senescent cells was present at the cultures derived from epididymal adipose tissue (P< 0.05).ConclusionOur data emphasize on the differences existed between the stem cells derived from adipose depots of different anatomical sites in terms of their proliferative capacity and in vitro aging. Such data can help understand varying results reported by different laboratories involved in adipose stem cell investigations.

Objective(s) The aim of this study was to investigate glycoconjugates distribution patterns as well as their changes during the course of pituitary portal vasculogenesis and angiogenesis.Materials and MethodsFormalin fixed paraffin sections of 10 to 20 days of Sprague Dawly rat fetuses were processed for histochemical studies using four different horseradish peroxidase (HRP) conjugated lectins. Orange peel fungus (OFA), Vicica villosa (VVA), Glycine max (SBA) and Wistaria floribunda (WFA) specific for α-L-Fucose, D-Gal, α, ß-D-GalNAc and D- GalNAc terminal sugars of glycoconjugates respectively.ResultsOur finding indicated that adenohypophysal cells reacted with OFA on gestational day 10 (E10) and increased progressively to E14. Staining intensity did not change from days 14 to17, then after increased following days to E20 significantly (P< 0.05). A few cells around Rathke’s pouch reacted with VVA on E13, increased to E14 and decreased significantly afterward (P< 0.05). Reaction of some cells around Rathke’s pouch reacted with SBA on E14. This visible reaction was the same as E18 and decreased later (P< 0.05). Many cells around Rathke’s pouch reacted with WFA on E13 and increased on E 14 and E15 and decreased thereafter (P< 0.05).ConclusionReactions of OFA and other tested lectins with endothelial cells around Rathke’s pouch and developing pars distalis were different. These results suggest that embryonic origin of hypophiseal pituitary portal (HPP) system endothelial cells are not the same and our finding also indicated that glycoconjugates with terminal sugars α-L-Fucose, D-Gal, α, ß-D-GalNAc may play critical role(s) in cell interactions and tissue differentiations such as vasculogensis and angiogenesis as well as other developmental precursors in formation of the pituitary gland.

Objective(s)Diabetes mellitus is associated with disturbances of learning and memory and cognitive functioning. Aegle marmelos Corr. from Rutaceae family is widely used in Iranian folk medicine for the treatment of diabetes mellitus. Considering the beneficial antidiabetic and antioxidant potential of A. marmelos, this study was conducted to evaluate the effect of oral administration of A. marmelos on learning and spatial memory in diabetic rats using Morris water maze test.Materials and MethodsConsidering the beneficial antidiabetic potential of A. marmelos, this study was conducted to evaluate the effect of chronic oral administration of A. marmelos as cognitive enhancer, on learning and spatial memory in diabetic rats using Morris water maze test. Male Wistar rats were randomly divided into normal-control, diabetic-control, and A. marmelos-treated diabetic groups (100, 250 and 500 mg/kg, p.o.). Animals were treated for 4 weeks by A. marmelos or normal saline. Diabetes was induced by a single dose i.p. injection of streptozotocin (45 mg/kg). In each group of animals, spatial learning and memory parameters were analyzed. ResultsClear impairment of spatial learning and memory was observed in diabetic group versus normal-control group. A. marmelos showed dose dependent improvement in spatial learning and memory parameters that swimming time (Escape Latency) in normal-control and A. marmelos-treated diabetic animals rats was significantly (P< 0.01) lower than diabetic-control, while swimming speed was significantly (P< 0.05) higher.ConclusionThe study demonstrated that A. marmelos has significant protective affect against diabetes-induced spatial learning and memory deficits. This effect could be attributed to hypoglycemic, hypolipidemic and antioxidant activity of A. marmelos.

Doxorubicin (DOX), a widely used chemotherapeutic agent can give rise to serve cardiotoxicity by inducing apoptosis. Curcumin, the active compound of the rhizome of Curcuma longa L. has anti-inflammatory, antioxidant and anti-proliferative activities. Curcumin has been identified to increase cytotoxicity in several cancer cell lines in combination with DOX, but there is no study about its effect and DOX on normal cardiac cells. Therefore, in the present study, we evaluated the effect of curcumin on apoptosis induced by DOX in H9c2 rat heart-derived cells. Materials and MethodsCell viability was determined by MTT assay. Also, activation of caspase-3 was evaluated by spectrophotometry. Quantitative real time RT-PCR was used to evaluate the expression of c-IAP1. Detection of intracellular DOX accumulation was performed by flow cytometry.ResultsNo toxicity observed when the cells exposed for 1 hr to different concentrations of curcumin, but pretreatment of cells with curcumin increased cytotoxicity of DOX in a dose dependent manner. Analysis of caspase-3 activation showed that curcumin pretreatment increased caspase-3 activation. RT-PCR analysis clearly showed that curcumin significantly decreased mRNA gene expression of c-IAP1 compared to cells treated with DOX alone. Pretreatment of H9c2 cells with DOX and curcumin had no effect on the intracellular accumulation of DOX. ConclusionOur observations indicated that subtoxic concentrations of curcumin sensitize H9c2 cells to DOX-induce apoptosis. These results suggest that the use of curcumin in combination with DOX in malignancy must be reevaluated.

Objective(s)Ibuprofen is a problematic drug in tableting, and dissolution due to its poor solubility, hydrophobicity, and tendency to stick to surface. Because of the bad compaction behavior ibuprofen has to be granulated usually before tableting. However, it would be more satisfactory to obtain directly during the crystallization step crystalline particles that can be directly compressed and quickly dissolved. Materials and Methods Crystallization of ibuprofen was carried out using the quasi emulsion solvent diffusion method in presence of surfactant (sodium lauryl sulfate (SLS), Tween 80). The particles were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRPD) and were evaluated for particle size, flowability, drug release and tableting behavior. ResultsIbuprofen particles obtained in the presence of surfactants consisted of numerous plate- shaped crystals which had agglomerated together as near spherical shape. The obtained agglomerates exhibited significantly improved micromeritic properties as well as tableting behavior than untreated drug crystals. The agglomerates size and size distribution was largely controlled by surfactant concentration, but there was no significant influence found on the tableting properties. The dissolution tests showed that the agglomerates obtained in presence of SLS exhibited enhanced dissolution rate while the agglomerates made in the presence of Tween 80 had no significant impact on dissolution rate of ibuprofen in comparison to untreated sample. The XRPD and DSC results showed that during the agglomeration process, ibuprofen did not undergo any polymorphic changes.Conclusion The study highlights the influence of surfactants on crystallization process leading to modified performance.

Objective(s)Matricaria aurea is found abundant in Iran and has large similarities in constituents especially essential oils, flavones and flavonoides as well as traditional uses to the main species; Matricaria recutita L. Anti-inflammatory, antioxidant and spasmolytic properties of the main species suggest that this plant may have beneficial effects on inflammatory bowel diseases so the present study was carried out.Materials and MethodsHydroalcoholic extract of plant with doses of 200, 400, 800 mg/kg were administered orally (p.o.) for 5 days and rectally (i.r.) (400 and 800 mg/kg) at 15 and 2 hr before ulcer induction. To induce colitis, 2 ml of acetic acid 4% was instilled intra-colonically to separate groups of male Wistar rats (n= 6). Normal saline (2 ml), prednisolone (4 mg/kg) and hydrocortisone acetate (20 mg/kg) enema were administered to control and reference groups respectively. The tissue injures were assessed macroscopically and histopathologically. ResultsGreater doses of extract (400 and 800 mg/kg) reduced colon weight/length ratio (P< 0.01) and the highest test dose (800 mg/kg p.o. or i.r.) was effective to decrease tissue damage parameters including ulcer severity, area and index (P< 0.01) as well as inflammation severity and extent, crypt damage and total colitis index (P< 0.01) significantly. ConclusionIt is concluded thatMatricaria aurea extract was effective to protect against acute colitis in acetic acid model and this effect was more significant with the greater doses administered orally or rectally. Further studies are warranted to ascertain the mechanisms that are involved and the responsible active constituents.

Objective(s)In this study, effects of chronic administration of oral natural honey against ischemia/reperfusion (I/R)-induced cardiac arrhythmias were investigated in isolated rat heart. Materials and MethodsMale Wistar rats were divided into four groups (n= 10-14 rats in each group) and fed with natural honey (1%, 2% and 4% dissolved in the drinking water) for 45 days except for the control group. After anesthesia, the rats’ hearts were isolated quickly, mounted on a Langendorff apparatus and perfused with a modified Krebs-Henseleit solution during stabilization, 30 min regional ischemia followed by 30 min reperfusion. The ECGs were recorded throughout the experiments to analyze cardiac arrhythmias based on the Lambeth conventions. ResultsIn the ischemic phase, honey (1%) significantly reduced (P<0.05) the number and duration of ventricular tachycardia (VT). Honey (1% and 2%) also significantly decreased number of ventricular ectopic beats (VEBs). In addition, incidence and duration of reversible ventricular fibrillation (Rev VF) were lowered by honey 2% (P<0.05). During reperfusion time, VT incidence was 73% in the control group, however natural honey (1%) decreased it to 22% (P<0.05). Honey also produced significant reduction in the incidences of total VF, Rev VF, duration and number of VT. ConclusionFor the first time, the results of present study demonstrated protective effects of chronic oral honey administration against I/R-induced arrhythmias in isolated rat heart. Antioxidant activity, the existence of energy sources such as glucose and fructose and improvement of some hemodynamic functions might be responsible for these effects.

Objective(s)The development of efficient and safe carrier system to transfer DNA into cells is essential in non-viral gene therapy. The aim of the present study was to evaluate the effect of linear polyetheneimine (lPEI) (2500 Da) on the physicochemical and biological properties of lipopolyplexes constructed from liposomes and lPEI. Materials and MethodsDifferent lipopolymers were synthesized from lPEI and acrylate derivatives. Nanocarriers were composed of the lipids (DOPE, DPPE and DOTAP) and the synthesized lipopolymers. After characterization of the prepared vectors by determination of size and zeta potential, transfection activity was tested in Neuro2A cells. Ethidium bromide and MTT test were used to evaluate the DNA condensation ability and cytotoxicity of vectors, respectively. Results Vector’s size ranged from 95 to 337 nm and they had positive charge. The differences in DNA binding properties of lipopolyplexes were not significant. Among lipids, DOTAP showed better impact on transfection efficiency. The highest transfection activity was achieved by liposomal formulation consist of DOTAP and lipopolymer composed of lPEI and hexyl acrylate. The lipopolyplexes showed minimum cytotoxicity to the cultured cells in vitro. Conclusion The results of study confirmed that it is possible to improve gene expression using lipopolyplexes.

Objective(s)Using herbal medicines as a complementary treatment method is increasing in wide variety of diseases. MS14-an herbal-marine preparation-is reported to have anti-inflammatory and immunomodulatory activities; however, the mechanism underlying its therapeutic effect is not known. Macrophages play an important role in host defense mechanisms and carry out their role by producing various mediators including proinflammatory cytokines (TNFa, IL-1b). In this study the effects of orally administered MS14 on TNFa and IL-1b production of BALB/c mice peritoneal macrophages were evaluated. Materials and MethodsMS14 at 100 mg/kg was orally administered for 5 days to BALB/c mice in MS14 group. Sterile normal saline was administered to mice in control group. Peritoneal macrophage were isolated from control and MS14 groups and cultured, then the supernatants were collected and the cytokines IL-1b and TNFa were measured by ELISA test.ResultsSignificant decrease in TNFa and IL-1bproduction of macrophages both at the presence and absence of stimulators was observed. TNFalevels were 64.7±4.6 and 51.1±4.2 pg/ml in drug and control groups respectively (P< 0.05) and 298.7±31.3 and 177.0±26.5 pg/ml in stimulated (PMA+fMLP) cultures of drug and control groups respectively (P< 0.007). The IL-1blevels was 130.1±2.8 pg/ml in control and 65.1±5.6 in MS14 group (P< 0.000).ConclusionIt could be concluded that MS14 is able to cause a decline in some inflammatory responses of immune system, which could be considered as at least one of its immunomodulatory mechanisms.

Objective(s)Diabetes related dysfunction of resistance vessels is associated with vascular occlusive diseases. Vasorelaxant agents may have a role in control of diabetic cardiovascular complications. Gamma aminobutyric acid (GABA) has demonstrated to cause vasorelaxation. The present study was designed to determine i) the vasorelaxatory effect of GABA on diabetic vessels and ii) the role of endothelium in GABA-induced vasorelaxation.Materials and MethodsAfter Diabetes induction,. Mesenteric arteries of animals were perfused. Vascular beds were constricted with phenylephrine. GABA (1 to 50 µM) was added into the medium and perfusion pressure was then recorded. ResultsIn all groups of animals, relaxant response to GABA in mesenteric bed appeared. Although diabetes induction did not change mesenteric bed response to GABA, denuded vessels showed a reduced response to GABA both in control and diabetic animals.ConclusionGABA can induce endothelium dependent vasorelaxation in mesenteric vessels in normal and diabetic rats.