Iranian Journal of Basic Medical Sciences
Year:2016 | Volume:19 | Issue:8|Papers Count:15

Objective(s): In food industry, the inhibition of tyrosinase is very important, because this enzyme catalyzes the oxidation of phenolic compounds found in fruits and vegetables into quinones, which contribute in undesirable color and taste of fruits and vegetables. Teucrium polium L. var. gnaphalodes (Lamiaceae), a wild-growing flowering plant that has many applications in food preparations and traditional medicine. In Persian language, this medicinal herb is called Kalpoureh. Materials and Methods: 1D-and 2D-NMR experiments were used to determine the chemical structures of the isolated compounds. Antioxidant and tyrosinase inhibitory activities of the isolated compounds were evaluated using DPPH, FRAP and mushroom tyrosinase inhibition assays. Results: In this research, we isolated two phenylpropanoid glycosides including verbascoside and poliumoside and two flavonoids including jaranol and isorhoifolin using chromatographic techniques. We found promising antioxidant and anti-tyrosinase compounds from Teucrium polium L. var. gnaphalodes. Conclusion: To date, different compounds have been isolated and characterized from T. polium including terpenoids and flavonoids. But no phytochemical study has been reported from T. polium var. gnaphalodes. Poliumoside and jaranol showed promising antioxidant and tyrosinase inhibitory activities, respectively.

Objective(s): Activation of acid-sensing ion channel 1a (ASIC1a) is responsible for tissue injury caused by acidosis in nervous systems. But its physiological and pathological roles in nucleus pulposus cells (NPCs) are unclear. The aim of this study is to investigate whether ASIC1a regulates the survival of NPCs in the acidic environment of degenerated discs. Materials and Methods: NPCs were isolated and cultured followed by immunofluorescent staining and Western-blot analysis for ASIC1a. Intracellular calcium ([Ca2+]i) was determined by Ca2+-imaging using Fura-2-AM. Cell necrosis, apoptosis, and senescence following acid exposure were determined using lactate dehydrogenase (LDH) release assay, annexin V-fluorescein isothiocyanate/propidium iodide dual-staining and cell cycle analysis, respectively, followed by Western-blot analysis for apoptosis-related proteins (Bax, Bcl-2, and caspase-3) and senescence-related proteins (p53, p21, and p16). Effects of treatment with psalmotoxin-1 (PcTX1, blocker of ASIC1a) on [Ca2+]i and cell survival were investigated. Results: ASIC1a was detected in healthy NPCs, and its expression was significantly higher in degenerated cells. When NPCs were treated with PcTX1, acid-induced increases in [Ca2+]i were significantly inhibited. PcTX1 treatment also resulted in decreased LDH release, cell apoptosis and cell cycle arrest in acid condition. Acid exposure decreased the expression of Bcl-2 and increased the expression of Bax, cleaved caspase-3 and senescence-related proteins (p53, p21, and p16), which was inhibited by PcTX1. Conclusion: The present findings suggest that further understanding of ASIC1a functionality may provide not only a novel insight into intervertebral disc biology but also a novel therapeutic target for intervertebral disc degeneration.

Objective(s): The aim of this study was to estimate effects of hyperbaric (HB) treatment by determination of CD15s and CD11b leukocyte proinflammatory markers expression. In addition, this study describes changes in CD77 and CD34 expression on rat endothelial cells in renal, pulmonary and cardiac tissue following exposure to hyperbaric pressure. Materials and Methods: Expression of CD11b and CD15s on leukocytes, as well as CD77 and CD34 expression on endothelial cells in cell suspensions of renal, pulmonary and cardiac tissue in rats after hyperbaric treatment and in control rats were determined by flow cytometry. Results: Hyperbaric treatment significantly increased percentage of leukocytes expressing CD15s+CD11b-(from 1. 71± 1. 11 to 23. 42± 2. 85, P<0. 05). Hyperbaric treatment significantly decreased sum percentage of CD77+CD34-and CD77+CD34+ renal cells (from 16. 35± 5. 5 to 4. 48 ± 1. 28, P<0. 05). Hyperbaric treatment significantly increased percentage of CD34+ pulmonary cells (from 3. 27± 2. 01 to 11. 92± 6. 22, P<0. 05). Our study is the first reporting the hyperbaric environment influence on CD34+ heart cells in rats. Conclusion: The current findings of increased percentage of leukocytes expressing endothelial selectin ligand CD15s after hyperbaric treatment, point its role in endothelial damage prevention. We found out a significantly increase in percentage of CD34+ cardiac cells as well as CD34+ pulmonary cells in rats after HB treatment which could be a part of repair mechanism of injured endothelium caused by hyperoxia.

Objective(s): We investigated the histopathological effects of metamizole sodium (MS) on the sciatic nerve. Materials and Methods: This study was performed using 48 adult male Wistar albino rats. Ten groups were constituted with 6 rats in each group. MS injection into the sciatic nerve (group 1), MS injection into the muscle [group 3 (50 mg/kg, 0. 4 ml) and group 5 (50 mg/kg, 0. 8 ml)], MS injection into the muscle cavity in the vicinity of the sciatic nerve [group 2 (50 mg/kg, 0. 4 ml) and group 4 (50 mg/kg, 0. 8 ml)], normal saline injection into the muscle in the vicinity of the sciatic nerve [group 6A (0. 4 ml) and 6B (0. 8 ml)], subjected to injury by drilling the entire layer of nerve without injecting any drug, normal saline injection in the sciatic nerve, and control group. Nerve and muscle samples were taken 7 days after administrations. Tissue sections were stained using a hematoxylin and eosin-Luxol® fast blue stain, assessed by a histologist. Results: The levels of axonal degeneration of the rats in groups 1, 2, 3, 4, 5, 6A, and 8 were found to be significantly higher compared to the levels of the rats in the control group (P<0. 05). Myelin degeneration of the rats in all groups was found to be significantly higher compared to myelin degeneration of the rats in the control group (P<0. 05). Conclusion: It was observed that MS could lead to injury in the sciatic nerve with a toxic effect due to diffusion.

Objective(s): To investigate the efficacy of interleukin 11 (IL-11) towards the high dose methotrexate (HDMTX)-concurrent rat small intestinal mucositis and its impacts on the proliferation of the human T-lymphoblastic leukemia (CEM) cell line. Materials and Methods: 95 Wistar rats were randomly divided into five groups, the normal control group (A), the methotrexate (MTX) control group (B), the IL-11-pre-treated high-dose group (C), the post-IL-11-treatment high-dose group (D) and the post-IL-11-treatment low-dose group (E). After the intraperitoneal injection of MTX in the groups B-E, the rats were sacrificed at 1, 3, 5 and 7 days. The mortality, morphological and ultrastructural changes of small intestine of each group were observed. The cells were then cultured in vitro, and the MTT method was used to investigate the effects of different concentration of IL-11 on CEM proliferation and also on HDMTX-induced mucositis. Results: IL-11 could reduce the intestinal histopathological score, increase the height of small intestinal villi, promote the proliferation of intestinal lacunar cells and reduce the mortality rate of rats. The IL-11 pre-treatment group exhibited the best efficacies, demonstrating significant difference with the control group (P<0. 01). In addition, the proliferation of CEM was not promoted, indicating that IL-11 could not inhibit HDMTX. Conclusion: IL-11 could reduce the severity of HDMTX-induced intestinal mucositis, and improve the survival rate of experimental rats, and could be safely used as the adjuvant treatment of HDMTX in childhood leukemia.

Objective(s): Tuberculosis is one of the most important infectious diseases with high mortality rates worldwide, especially in developing countries. Interleukin17 (IL-17) is an important acquired immunity cytokine, which is mainly produced by CD4+TH17 cells. It can recruit neutrophils and macrophages to the infected site in the lungs. IL-23 is one of the most important inducers of IL-17. In the present study, the expressions of IL-23 and IL-17 were examined in the pathogenesis of tuberculosis. Materials and Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from subjects with latent tuberculosis infection (LTB) and newly diagnosed active tuberculosis patients (ATB). PBMCs were activated with purified protein derivative (PPD) for 72 hr. Activated cells were harvested, RNA was extracted, and cDNA was synthesized. IL-17 and IL-23 mRNA expressions were evaluated by real-time PCR. The frequency of Th17 cells was examined by flowcytometry. Results: The expressions of IL-17 and IL-23 mRNA were lower in patients than subjects with LTB (P<0. 05). The frequency of IL-17 producing CD4+ T cells in patients with active TB was lower than LTB subjects (P<0. 05). Conclusion: The results of the present study might suggest that IL-17 and IL-23 play critical roles in the immune response against TB.

Objective(s): Although low-dose radiotherapy (RT) that involves low collateral damage is more suitable for hepatocellular carcinoma (HCC) than traditional high-dose RT, but to achieve satisfactory therapeutic effect with low-dose RT, it is necessary to sensitize HCC cells to irradiation. This study was aimed to determine whether radiosensitivity of HCC cells can be enhanced using miR-26b by targeting erythropoietin producing human hepatocelluar A2 (EphA2). Materials and Methods: The levels of miR-26b and EphA2 expression in multiple HCC cell lines were assessed by qPCR and western blotting, respectively, and compared with those in a hepatic cell line. HCC 97H cells were transfected with miR-26b mimics, EphA2-ShRNA or EphA2 over-expression vector before exposure to low-dose irradiation. Results: Different degrees of miR-26b down-regulation and EphA2 up-regulation were observed in all HCC cell lines, among which the HCC 97H cell line expressed the lowest level of miR-26b and highest level of EphA2. EphA2 was verified as the target of miR-26b by dual luciferase reporter assay. HCC 97H cells transfected with miR-26b mimics or EphA2-ShRNA reduced the expression of EphA2 protein, with significantly lower cell proliferation rate and cell invasion ability and higher apoptosis rate in response to low-dose irradiation than those in the non-transfected cells. These results were reversed after EphA2 was overexpressed by transfection with the EphA2 overexpression vector. Co-transfection with miR-26b mimics and EphA2 overexpression vector barely altered EphA2 expression level and cell response to low-dose irradiation. Conclusion: These data suggest that miR-26b enhances radiosensitivity of HCC 97H cells by targeting EphA2 protein.

Objective(s): Epidermolysis bullosa is one of the most important series of mechano-bullous heritable skin disorders which is categorized into four major types according to the layer that bullae forms within basement membrane zone. In dystrophic form of the disease, blisters are made in the sublamina densa zone, at the level of type VII collagen protein which produce anchoring fibrils. Type VII collagen gene is the only responsible gene for this form. The aim of this study was to survey causative mutations of type VII collagen gene among Iranian patients with epidermolysis bullosa. Materials and Methods: For this purpose, exons 73-75 were investigated by polymerase chain reaction followed by direct sequencing. Results: In current study, we found three different point mutations in type VII collagen alleles in 7 out of 50 patients. Four patients were homozygous for a new deletion which resulted in frame shift (p. Pro2089fs). Two patients were homozygous for a recurrent glycine substitution (p. G2031S) and one patient was detected with an allele carrying a substitution (p. R2069C). Conclusion: The results emphasized heterogeneity in the type VII collagen gene and will provide a sign for early diagnosis and future study of the disease pathogenesis.

Objective(s): Several researchers have reported the relationship between infertility in male and varicocele for so many years but the implication of varicocele in female patients is remains elusive. Here, we aim to examine the effects of unilateral varicose ovarian vein on antioxidant capacity and oocyte quality of rat ovary after the experimental creation of varicocele in female rats. Materials and Methods: In this study, thirty adult female albino rats were divided into three equal groups: Group 1 as the control group has 10 rats, Group 2 as the sham group has 10 rats and they underwent a sham operation and finally Group 3 has the varicocele group has 10 rats. Antioxidant assays for superoxide dismutase, glutathione peroxidase and catalase were performed using specific assay kits and gene expression for Bax, Bmp-15, Hsp-27 and Gdf-9 was done via real time PCR. Results: The adverse effects of the experimentally induced varicocele were reported and recorded on the left ovary compared to the right sided ovary (no varicocele induction) in the varicocele group. Real time PCR data shows that the expression of Gdf-9, Hsp-27 and Bmp-15 genes were all significantly reduced at p≤ 0. 05. Conclusion: The results of this study show that reduced gene expression of Bmp-15, Gdf-9 and Hsp-27, increased gene expression of bax and an imbalance between pro-oxidant/ antioxidant ratio are few of the several mechanisms by which varicocele may lead to infertility in female.

Objective(s): Longan seeds have been used as a folk medicine in China. Longan seed extract (LSE) is known for antioxidative, antiproliferative, hypoglycemic, and hypouremic effects. However, its anti-inflammatory effect has not been shown. Materials and Methods: In this study, Sprague-Dawley (SD) rats were given LSE orally (vehicle, 10, and 30 mg/kg) for 3 days to its test anti-inflammatory effect by injecting λ-carrageenan (CARR) in the right hind paw or lipopolysaccharide (LPS), IP. For the positive control, animals were given aspirin (20 mg/kg) orally and treated likewise. Serum or tissue samples from treated rats were collected after 3 hr of stimulation. Regarding the in vitro study, BV2 microglial cells were stimulated with LPS in the presence of LSE or normal saline for 10 min or 24 hr for Western blot and ELISA assay, respectively. Results: LSE reduced CARR-induced edema in the experimental animals. LSE also reduced LPS/CARR-induced nitric oxide (NO), interleukin-1β (IL1β ), IL6, and COX2 productions. These inflammatory factors were also reduced dose dependently by LSE in LPS-stimulated BV2 cells. Furthermore, Western blot analysis revealed that LSE inhibited LPS activated c-Jun NH2-terminal protein kinase (JNK), extracellular signal-regulated kinases (ERKs), and p38 MAP kinases signaling pathways, caspase-3, inducible NO synthase, and COX2 expressions. Conclusion: LSE pretreatment suppressed CARR-and LPS-induced inflammations and these effects might be through the inhibition of MAP kinases signaling pathways and inflammatory factors.

Objective(s): Hyperthermia is one of the most common environmental stressors that affect multi-biological systems in the body including the central nervous system as well as the hematopoietic organs. The objective of the present study was to investigate the protective role of ethanolic extract of propolis (EEP) on some selective stress markers, hematological, biochemical, and histopathological changes in rats subjected to hyperthermia (40 ° C/12 hr). Materials and Methods: The experimental groups (10 rats each) were classified as follows; Group A; control, (C), was kept at a controlled room temperature (25± 5 ° C). Group B; ethanolic extract of propolis, (EEP), was fed a basal diet supplemented with 3 g EEP/kg diet for 10 days. Group C; heat stress, (HS), was fed a basal diet for 10 days, and then exposed to high temperature (40± 1 ° C) for 12 hr. Group D; co-exposed, (EEP+HS) was fed a basal diet supplemented with 3 g EEP/kg diet for 10 days, and then subjected to high temperature (40± 1 ° C) for 12 hr. At the end of the experimental period, animals were decapitated; blood and tissue samples (brain and spleen) were collected for hematological, biochemical, and histopathological examination. Results: EEP at a dose of 3 g/kg diet has a potent protective effect against hematotoxicity and brain damage as well as oxidative stress induced by heat stress in rats. Conclusion: The present study indicates that pre-treatment with EEP protects from hematotoxicity and neurological damage induced by high environmental temperature.

Objective(s): Enterotoxigenic Escherichia coli (ETEC) strains are one of the primary causes of diarrhea in newborn calves and in humans, pigs, and sheep. IgY technology has been identified as a promising alternative to generating a mass amount of specific antibody for use in immunotherapy and immunodiagnostics. The purpose of this study was to produce specific antibody by egg yolk antibody (IgY) to recombinant FanC protein from ETEC. Materials and Methods: FanC (K99) gene was amplified from ETEC by specific primers and polymerase chain reaction. The gene was cloned and subcloned into pTZ57R/T and pET32a (+) vectors, respectively. Recombinant vector was transferred into E. coli BL21 CodonPlus (DE3). Protein expression was investigated by 1 mM IPTG induction. Hens were immunized by the purified recombinant FanC protein. The activity and specificity of the IgY antibody were detected by dot-blotting, Western blotting, and indirect ELISA. Results: We obtained FanC specific IgYs by immunizing the hens with the recombinant FanC protein. The anti-FanC IgY showed binding specifically to the FanC protein of ETEC. Conclusion: The results emphasize that specific IgY against the recombinant FanC protein could be recommended as a candidate for passive immunization against ETEC infection in animals and humans.

Objective(s): Glioblastoma multiforme (GBM) is one of the most lethal forms of human cancer and temozolomide (TMZ) is currently part of the standard treatment for this disease. Combination therapy using natural substances can enhance the anti-cancer activity of TMZ. The purpose of this study was to evaluate the effect of TMZ in combination with thymoquinone (TQ) on human GBM cell line (U87MG). Materials and Methods: The cell line was treated with TMZ and/or TQ. Cell viability was assessed using trypan blue and MTT assay. The effect of TMZ and/or TQ on colony-forming ability of the cells was investigated. Apoptosis and autophagy were quantified by fluorescent dye staining. The expression level of two autophagy related genes (ATG) were assessed using RT-PCR. Furthermore, nitric oxide (NO) production was detected by Griess reaction. Results: After treatment with TMZ and/or TQ, the cell viability was reduced in a time-and dose-dependent manner, and the cell survival fraction (SF) was significantly decreased (P=0. 000). Apoptosis index of U87MG cells was also significantly increased (P=0. 000). Autophagy was significantly increased by TMZ (P=0. 000) and decreased by TQ (P=0. 018). Also TMZ and/or TQ significantly decreased NO production by U87MG cell (P=0. 000). Conclusion: TQ enhanced the anti-cancer activity of TMZ by inhibition of autophagy at the transcriptional level and decreased the colony-forming ability and NO production of U87MG cell line.

Objective(s): There are few reports have demonstrated the effect of a change-in-light experience on the structure and function of hippocampus. A change-in-light experience also affects the circadian pattern of melatonin secretion. This study aimed to investigate developmental effect of exogenous melatonin on synaptic plasticity of hippocampus of light deprived rats. Materials and Methods: The effects of intracerebroventricular (ICV) injection of 2μ g/5μ l melatonin was evaluated on the basic and tetanized field excitatory post-synaptic potentials (fEPSPs) recorded in the hippocampal CA3-CA1 pathway of normal light-reared (LR) and dark-reared (DR) rats at 2, 4, and 6 weeks of age. Using RT-PCR and western blotting, developmental changes in the expression of melatonin receptors, MT1 and MT2, in the hippocampus were also evaluated. Results: The amplitude of basic responses decreased across age in the LR rats. While light deprivation increased the amplitude of baseline fEPSPs, it decreased the degree of potentiation in post-tetanus responses. Melatonin injection also increased the amplitude of fEPSPs and suppressed the induction of long-term potentiation in both LR and DR rats. The expression of melatonin receptors increased in the hippocampus during brain development, and dark rearing reversed the expression patterns of both receptors. Conclusion: Although melatonin changed basic and tetanized responses of CA1 neurons across age during critical period of brain development, the pattern of its effects did not match the expression pattern of melatonin receptors in the hippocampus. Thus, the effects of melatonin on hippocampal neuronal responses may be exerted through other ways, like intercellular molecules and nuclear hormone receptors.

Objective(s): The objective of this study was to investigate the hepatoprotective effect of licochalcone B (LCB) in a mice model of carbon tetrachloride (CCl4)-induced liver toxicity. Materials and Methods: Hepatotoxicity was induced in mice by a single subcutaneous injection (SC) of CCl4. The LCB was administered orally once a day for seven days (PO) as pretreatment at three doses of 1, 5, and 25 mg/kg/day. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α ), interleukin-6 (IL-6), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed by ELISA. The protein expression degrees of p38 mitogen activated protein kinases (p38) and nuclear factor-k-gene binding (NF-κ B) were assayed by western blotting. Results: CCl4-induced hepatotoxicity was manifested by an increase in the levels of ALT, AST, MDA, IL-6, CRP, and TNF-ɑ , and a decrease in the SOD level and GSH/GSSG ratio in the serum. The histopathological examination of the liver sections revealed necrosis and inflammatory reactions. Pretreatment with LCB decreased the levels of ALT, AST, MDA, GSSG, IL-6, CRP, TNF-ɑ , and the protein expression of p38 and NF-κ B, increased the level of SOD and GSH, and normalized the hepatic histo-architecture. Conclusion: LCB protected the liver from CCl4-induced injury. Protection may be due to inhibition of p38 and NFκ B signaling, which subsequently reduced inflammation in the liver.