Iranian Journal of Basic Medical Sciences
Volume:18 Issue: 8, Aug 2015

Sulfur mustard (SM, bis- (2-chloroethyl) sulphide) is a chemical warfare agent that causes DNA alkylation, protein modification and membrane damage. SM can trigger several molecular pathways involved in inflammation and oxidative stress, which cause cell necrosis and apoptosis, and loss of cells integrity and function. Epigenetic regulation of gene expression is a growing research topic and is addressed by DNA methylation, histone modification, chromatin remodeling, and noncoding RNAs expression. It seems SM can induce the epigenetic modifications that are translated into change in gene expression. Classification of epigenetic modifications long after exposure to SM would clarify its mechanism and paves a better strategy for the treatment of SM-affected patients. In this study, we review the key aberrant epigenetic modifications that have important roles in chronic obstructive pulmonary disease (COPD) and compared with mustard lung.

In this study, we aimed at evaluation of electrophysiological and histopathalogical characteristics of statin-induced muscle injury as well as clinical features of patients who develop this condition in terms of frequency and pattern of evolution. Forty patients (age 39-74 years) including 25 subjects with type 2 diabetes mellitus, 9 with cardiovascular diseases and 6 with hyperlipidemia, who were receiving atrovastatin 40 mg/day for variable period, were studied. Thirty three healthy subjects (age 31-74 years) served as control group. Creatine phosphokinease level, thyroid function, motor unit potential parameters and muscle fiber conduction velocity of biceps brachii and tibialis anterior muscles were measured. Creatine phosphokinase level was elevated in statin users, particularly in those with diabetes mellitus. Less than 50% of statinusers experienced symptoms related to muscle injury. Muscle fiber conduction velocity of the biceps brachii muscle was significantly reduced. Statinusers with diabetes mellitus showed significant changes in electrophysiological parameters as compared to those with cardiovascular diseases and hyperlipidemia. Muscle biopsies showed muscle fiber variation in size, fibrosis and mild inflammatory cell infiltration. Immunohistochemical evaluation of muscle biopsies showed positive expression of Bcl-2 and one patient showed positive P53 immunohistochemical expression with elevated level of creatine phosphokinase. Atorvastatin increased average creatine kinase, suggesting, statins produce mild muscle injury even in asymptomatic subjects. Diabetic statin users were more prone to develop muscle injury than others. Muscle fiber conduction velocity evaluation is recommended as a simple and reliable test to diagnose statin-induced myopathy instead of invasive muscle biopsy.

In this study the effect of oral administration of honey on serum glucose, lipids, stress oxidative markers, and morphology of langerhans islets in noise induced hyperglycemic rats was investigated. Male Wistar rats were divided into control, hyperglycemic, honey treated control, and honey treated hyperglycemic groups. For induction of hyperglycemia, noise stress was used. Serum glucose, triglyceride (TG), total cholesterol, low density lipoprotein (LDL), and high density lipoprotein (HDL)-cholesterol levels were determined before the study and at 4th and 8th weeks after the study. Markers of oxidative stress in brain were also measured. Morphology of langerhans islets in four groups was evaluated using Gomori staining method. Treatment of noise induced hyperglycemic rats with honey produced a hypoglycemic effect and appropriate changes regarding serum lipids in treated diabetic group at 4th and 8th weeks as compared to the control group. Meanwhile, honey treatment significantly ameliorated the increased malondialdehyde (MDA) content and reduced the activity of superoxide dismutase (SOD) in brain. Histology of langerhans islets in hyperglycemic group showed a lower number and granularity of beta cells; honey treatment produced beneficial change in this respect. Oral administration of honey in experimental model of diabetes showed a significant hypoglycemic effect and led to appropriate changes in serum lipid profiles.

Neuropathic pain remains a clinical problem and is poorly relieved by conventional analgesics. This study was designed to determine whether maprotiline administration was effective in alleviating symptoms of neuropathic pain and whether the antinociceptive effect of maprotiline mediated through the opioid system. Neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve in rats, which resulted in thermal hyperalgesia, and mechanical and cold allodynia. Maprotiline (10, 20 and 40 mg/kg, IP) was administered on the 7th and 14th days after surgery. To study the role of the opioid system in the antinociceptive effects of maprotiline, maprotiline (20 mg/kg, IP) was administered in combination with naloxone (1 mg/kg, SC) on the 7th post-surgery day. Behavioral tests were done at 45 min after drug injections on the 7th and 14th days after surgery. Systemic administration of maprotiline blocked heat hyperalgesia, cold allodynia and reduced mechanical allodynia. Also antihyperalgesic effect of maprotiline was reversed by pretreatment with naloxone. Our results suggest that maprotiline can be considered a potential therapeutic for the treatment of neuropathic pain, and the opioid system may be involved in the antihyperalgesic effects of maprotiline.

The inhibitory effects of iron chelators, and FeCl3 chelation on biofilm formation and swarming motility were investigated against an opportunistic human pathogen Pseudomonas aeruginosa. The inhibitory activity of 2,2’-bipyridyl, lipoic acid, kojic acid and picolinic acidonbiofilm formation of P. aeruginosa strain PAO1 and three clinical isolates (P. aeruginosa PAK01,P. aeruginosa PAK02 and P. aeruginosa PAK03) were investigated, based on crystal violet assay, and swarming motility test. The kojic, lipoic and picolinic acid inhibited biofilm formation by 5-33% in all tested P. aeruginosa isolates. When chelated iron was added, biofilm inhibition rates were determined to be 39-57%. Among the tested chelators against P. aeruginosa, lipoic acid (84%) and kojic acid (68%) presented the highest inhibition of swarming motility. This is the first study to report the inhibitory effect of lipoic acid on biofilm formation and swarming motility of P. aeruginosa. It is considered that lipoic and picolinic acids can serve as alternatives for the treatment of the P. aeruginosa infections by inhibiting biofilm formation.

Covering tissue defects using skin flaps is a basic surgical strategy for plastic and reconstructive surgery. The aim of this study was to evaluate the effects of chicken embryo extract (CEE) and bone marrow derived mesenchymal stem cells (BM-MSCs) on random skin flap survival (RSF) in rats. Using chicken embryo extract can be an ideal environment for the growth and proliferation of transplanted cells. Forty albino male Wistar rats were divided into 4 groups; each group consisted of 10 rats. BM-MSCs and CEE were transplanted into subcutaneous tissue in the area, where the flap would be examined. On the 7th postoperative day, the survival areas of the flaps were measured by using digital imaging with software assistance, and tissue was collected for evaluation. Survival area was 19.54±2 in the CEE group and 17.90±2 in the CEE/BM-MSC group when compared to the rates of the total skin flaps, which were significantly higher than the control group (13.47±2) (P<0.05). The biomechanical assessment showed a slight difference, although there was no statistically significant difference between the experimental groups and the control group (P>0.05). The findings from this study demonstrated that in operative treatment with BM-MSCs and CEE transplantation could promote flap survival, but the biomechanical parameters were not contrasted with a saline injection.

N-myc downstream regulated gene 2 (NDRG2) is a candidate gene for tumor suppression. The expression of NDRG2 is down-regulated in several tumors including lung cancer. The aim of this study was to explore the effect of NDRG2 overexpression on invasion, migration, and enzymatic activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in human lung adenocarcinoma A549 cells. A recombinant plasmid encoding green fluorescent protein (GFP)-tagged NDRG2 (pCMV6-AC-NDRG2-GFP) was used to overexpress GFP-tagged NDRG2 in A549 cells. The cells in the experimental group and those in the control group were transfected with pCMV6-AC-NDRG2-GFP and a control plasmid without NDRG2 (pCMV6-AC-GFP), respectively. Fluorescent microscopy and flowcytometry analysis of GFP expression were used to evaluate the cellular expression of GFP-tagged NDRG2 and the efficiency of transfection. The effects of NDRG2 expression on cell invasion and migration were evaluated using transwell filter migration assay. The gelatinase activity of secreted MMP-2 and MMP-9 was measured by gelatin zymography. Our results demonstrated the expression of GFP-tagged NDRG2 in the cytoplasm and nucleus of A549 cells. The findings of transwell assay showed that NDRG2 overexpression reduced migration and invasion of A549 cells compared to control cells. Gelatin zymography analyses revealed that NDRG2 overexpression decreased the gelatinase activity of secreted MMP-2 and MMP-9. These findings suggest that NDRG2 may be a new anti-invasion factor in lung cancer that inhibits MMPs activities.

Up to now, many researches have been performed to improve the antitumoral effect of melanoma differentiation-associated gene-7 (mda-7) protein. The purpose of our research was to construct 3 expression vectors producing mda-7 in fusion with RGD (Arginine-Glycine-Aspartic acid) peptide and evaluate their expression. mda-7 gene with two different RGD sequences was amplified by PCR then was cloned by TA–cloning system. The colonies including these genes were selected by blue–white screening, colony PCR, and sequencing, respectively. Afterward, the genes were sub-cloned into the expression vector following confirmation by colony PCR and sequencing. In addition, these constructs were transfected into 293 and Huh-7 cells for further expression analysis. The mda-7 gene expression was evaluated by RT-PCR and IF (immunofluorescence assay). DNA laddering test and trypan blue exclusion assays were performed to screen cytotoxicity of prepared plasmids. Three different mda-7 genes with terminal RGD peptide were cloned correctly into the expression vectors and their expression was confirmed to be suitable by RT-PCR and IF assay. It was shown that expressions were limited to those transfected, GFP shining cells. No significant cytotoxicity was observed by simple assays in all plasmid treated cells. In expressing cells, all forms of mda-7 protein were localized mainly around ER prenuclear compartment while GFP protein was distributed evenly among them. Theoretically RGD tagged mda-7 would be able to induce apoptosis with more specificity and stronger than the standard one, therefore, these new constructs may have the potential for further researches.

Use of biological scaffolds and automating the cells directing process with materials such as growth factors and glycosaminoglycans (GAGs) in a certain path may have beneficial effects in tissue engineering and regenerative medicine in future. In this research, chondroitin sulfate sodium was used for impregnation of the scaffolds. It is a critical component in extracellular matrix and plays an important role in signaling pathway; however, little is known about its role within mammalian development and cell linage specification. Due to its porous and appropriate structure and for putting cells in 3D space, the kidney of BALB/c mouse was selected and decellulalized using physical and chemical methods. After decellularization, the scaffold was impregnated in chondroitin sulfate solution (CS) for 24 hr. Then, 60×10 5 human adipose-derived mesenchymal stem cells were seeded on the scaffold to assess their behavior on day 5, 10, 15, 20, and 25. After 48 hr, DAPI staining approved completed decellularized kidney by 1% SDS (sodium dodecyl sulfate). Migration and establishment of a number of cells to the remaining area of the glomerulus was observed. In addition, cell accumulation on the scaffold surface as well as cells migration to the depth of kidney formed an epithelium-like structure. Up to the day 15, microscopic study of different days of seeding showed the gradual adhesion of large number of cells to the scaffold. Glycosaminoglycan could be a right option for impregnation. It is used for smartification and strengthening of natural scaffolds and induction of some behaviors in stem cells.

Estrogen is a sexual hormone that has prominent effects on reproductive and non-reproductive tissues. The aim of this study is to evaluate the effects of estrogen on the proliferation and neural differentiation of human adipose derived stem cells (ADSCs) during neurogenic differentiation. Isolated human ADSCs were trans-differentiated in neural induction medium containing neurobasal medium, N2 and B27 with or without 17β-estradiol (E2) treatment. Proliferation rate and neural differentiation of human ADSCs were assessed using MTT assay, immunostaining and real time RT- PCR analysis, respectively. Analysis of data show that estradiol treatment can significantly increase proliferation rate of differentiated cells (P<0.05). Immunocytochemical and real time RT-PCR analysis revealed that the expression of precursor and mature neuronal markers (nestin and MAP2) was significantly higher in the E2 treated cell cultures when compared to the untreated cell cultures (P<0.05). According to our findings, estrogen can promote proliferation and neuronal differentiation of human ADSCs.

Lectin-like low density lipoprotein receptor (LOX-1) has pivot role in vascular complications, which is upregulated in numerous pathological conditions. Since exercise has beneficial effects in prevention of hyperlipidemic complications, present study examined protective effects of aerobic exercise through reduction of LOX-1 expression in heart during dyslipidemia. Four groups of rats were used (N=25): Normal, Normal and exercise, High fat and High fat and exercise. High fat diet (HFD) was made by adding 10% animal oil, 2% cholesterol and 0.5% colic acid to standard rodent chow. Exercise protocol consisted of swimming 1 hr/day, and 5 days/week for 8 weeks. Plasma lipids were evaluated at the end of experiment, 48 hr after final session of exercise. At the end, rats were sacrificed and heart was removed for determination of malondialdehyde (MDA) content, and LOX-1 expression. HFD meaningfully changed lipid profile (>50%), but chronic exercise had no significant effects on lipid profile. LOX-1 expression was significantly increased in heart of rats fed with HFD, while swimming exercise considerably reduced gene expression of LOX-1. MDA content was significantly enhanced in rats fed with HFD (4.37±0.6 nmol/mg, P<0.01) compared to normal group (1.56±0.48 nmol/mg), whereas swimming exercise decreased MDA level of heart in rats fed with HFD (2.28±0.32, P<0.01). Findings indicated that swimming exercise is able to diminish heart expression of LOX-1 receptor concomitant reduction of oxidative stress. Since these parameters are involved in generation of dyslipidemic complications, swimming exercise is a good candidate to reduce these complications.

Degradation of sphingosine 1-phosphate (S1P), as a bioactive lipid, or deregulation of its production involves in tumor progression, metastasis and chemoresistance. Since the tumor progression effects of S1P and its mechanism in chronic lymphoblastic leukemia and non-small cell lung cancer is not fully understood, we investigated the role and one of the mechanisms of S1P in tumor progression of SKW3 and H1299 cells. The effects of S1P on proliferation, invasion and migration was studied using MTT assay, soft-agar colony forming assay and trans-well migration assay, respectively. In order to find out the mechanisms of S1P action, the role of S1P on expression of Survivin gene was assessed by real-time RT-PCR. Our results demonstrated that although invasion was shown only in H1299 cells, low concentration of S1P, especially at 1 μM, mediated proliferation and migration in both cell lines. In addition, these effects of S1P in tumor progression are S1P receptor-dependent, and Survivin plays a key role in S1P tumorigenesis. Our results confirmed the involvement of S1P and its receptors in tumor progression of SKW3 and H1299. We also investigated another mechanism of S1P involved in cell survival, tumor progression, and Survivin signaling. In conclusion, data demonstrated the importance of this molecule as a target for designing new anticancer drugs such as anti-S1P monoclonal antibody for inhibiting major downstream signaling, which plays significant role in tumorigenesis.

Propofol (2, 6-diisopropylphenol) is an intravenous anesthetic that is commonly used for the general anesthesia. It is well known that the spinal cord is one of the working targets of general anesthesia including propofol. However, there is a lack of investigation of the effects of propofol on spinal dorsal horn which is important for the sensory transmission of nociceptive signals. The objective of this study was to investigate the effects of increasing dosage of propofol on the release of glutamate (Glu), γ-aminobutyric acid (GABA) and glycine (Gly) in the spinal dorsal horn. The efflux of Glu, GABA or Gly in the spinal dorsal horn of rats was detected using transverse spinal microdialysis under an awake condition and various depths of propofol anesthesia. The infusion rates of propofol were, in order, 400 µg/(kg·min), 600 µg/(kg·min) and 800 µg/(kg·min), with a 20 min infusion period being maintained at each infusion rate. Propofol decreased the glutamate efflux within spinal dorsal horn in a dose-dependent manner, and the maximum decrease was 56.8 ± 6.0% at high-dose propofol infusion producing immobility. The inhibitory GABA and Gly efflux was also decreased about 15–20% at low-dose propofol infusion only producing sedation, but did not continue to drop with higher doses of propofol. Propofol decreased both excitatory and inhibitory amino acids efflux in spinal dorsal horn, and the preferential suppression of the excitatory amino acid might be associated with the analgesic effect of propofol.

Cyclophosphamide (CP) toxicity on testis was hampered by squid ink polysaccharide (SIP) via restoration of antioxidant ability in our previous investigations. This study investigated roles of Nrf2/ARE signal pathway in testis of treated mice. Male Kunming mice were employed to undergo treatment with SIP and/or CP. Protein levels of Nrf2, keap-1, histone deacetylase 2 (HDAC2), quinone oxidoreductase 1 (NQO-1), and heme oxygenase 1 (HO-1) and phosphorylation level of protein kinase C (PKC) in testis were evaluated by Western blotting. Data showed that SIP elevated expressions of NQO-1 and HO-1 genes, two downstream target molecules of Nrf2, via activating Nrf2 to play preventive roles on CP-treated testis, and further discovered that upstream regulators of Nrf2, keap-1, HDAC2, and PKC, were concerned with the regulation of Nrf2. These results suggest that SIP could effectively weaken CP-associated testicular damage via Nrf2/ARE signal pathway.

Non-alcoholic steatohepatitis (NASH), is an important component of Non-alcoholic fatty liver disease (NAFLD) spectrum, which progresses to the end stage liver disease, if not diagnosed and treated properly. The disproportionate production of pro- and anti-inflammatory adipokines secreted from fat contributes to the pathogenesis of NASH. In this study, the comparative effect of pioglitazone, quercetin and hydroxy citric acid on extracellular matrix (ECM) component levels were studied in experimentally induced NASH. The experimental protocol consists of using 48 male Wister rats, which were divided into 8 groups. The levels of hyaluronic acid, leptin and adiponectin were monitored in experimental NASH. The experimental NASH rats treated with pioglitazone showed significant decrease in the levels of hyaluronic acid and significant increase in adiponectin levels when compared to experimentally induced NASH group, but did not show any effect on the levels of leptin. Contrary to these two drugs, viz. pioglitazone and hydroxy citric acid, the group treated with quercetin showedsignificant decrease in the levels of hyaluronic acid and leptin and significant decrease in adiponectin levels compared with that of experimentally induced NASH NASH group, offering maximum protection against NASH. Considering our findings, it could be concluded that quercetin may offer maximum protection against NASH by significantly increasing the levels of adiponectin, when compared to pioglitazone and hydroxy citric acid.