فهرست مطالب

Iranian Journal of Basic Medical Sciences
Volume:23 Issue: 1, Jan 2020

  • تاریخ انتشار: 1398/09/09
  • تعداد عناوین: 18
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  • Leila Arabi, Bizhan Malaekeh Nikouei, Ali Roohbakhsh, Bibi Sedigheh Fazly Bazzaz * Pages 1-2
  • Ali Veisi, Ghaidafeh Akbari *, Ali Mard, Gholamreza Badfar, Vahid Zarezade, Mohammad Ali Mirshekar Pages 3-12

    Cancer is a major public health problem worldwide. The most important considerable features of cancer cells are uncontrolled proliferation, up-regulated differentiation, and immortality. Crocin, as a bioactive compound of saffron and as a water-soluble carotenoid has radical scavenging, anti-hyperlipidemia, memory improving, and inhibition of tumor growth effects. The present review was designed to evaluate molecular mechanisms underlying crocin effects against cancer cell lines. Data of this review have been collected from the scientific articles published in databases such as Science Direct, Scopus, PubMed, and Scientific Information Database from 1982 to 2019. According to various literature, crocin inhibits tumor growth, and its spread in several types of cancer including colorectal, pancreatic, breast, and prostate, as well as chronic myelogenous and leukemia. It inhibits telomerase activity, microtubule polymerization, cyclin D1, nuclear factor kappa B (NF-kB), multidrug resistance-associated protein (MRP1), and MRP2 overexpression. Crocin can induce apoptosis through activation of caspase 8, up-regulation of p53 expression, Bax/Bcl-2 ratio, and down-regulation expression of Bcl-2, survivin, and cyclin D1. It also down-regulates matrix metalloproteinase 2 and 9 (MMP2 and MMP9), N-cadherin, and beta-catenin expression, which are involved in tumor invasion and metastasis. Tumor invasion was also inhibited by crocin through increasing E-cadherin expression, cell cycle suppression at G1, G0/G1, S, and G2/M phases. Crocin has therapeutic and preventive effects on cancer cells line. Therefore, it has been suggested that this agent can be administered in patients that suffer from this problem.

    Keywords: Cancer, Cell line, Crocin, Review, Tumor
  • Nooshin Ghayemi, Farshid Sarafzadeh*, Hassan Malekinejad, Mehdi Behfar, Amir Abbas Farshid Pages 13-19
    Objective(s)

    Tendon healing is substantially slow and often associated with suboptimal repair. Cell therapy is one of the promising methods to improve tendon repair. Blastema, a population of undifferentiated cells, represents characteristics of pluripotent mesenchymal stem cells and has the potentials to be used in regenerative medicine. The aim of this study was to investigate the use of blastema allotransplantation in rabbit tendon healing.

    Materials and Methods

    In this study, one rabbit was used as a blastema donor, and twenty-four rabbits were divided into control and treatment groups. Blastema cells were obtained from ear pinna upon punch hole injury in the donor rabbit. Under general anesthesia, a complete transverse tenotomy was performed on the midsubstance of deep digital flexor tendon followed by suture-repair. In the treatment group, 1 × 106 blastema cells suspended in buffer saline were injected intratendinously at the repair site, while the control group received only the buffer saline. Cast coaptation was maintained for two weeks. Eight weeks after the operation, tendons were harvested, and histopathological, biomechanical, and biochemical assays were performed on samples.

    Results

    Mechanical testing showed a significant increase in ultimate load, energy absorption, stiffness, yield load, stress, and strain in blastema-treated tendons compared to controls. Also, higher hydroxyproline content and improved collagen alignment along with lower inflammatory cell infiltration and decreased angiogenesis were observed in blastema-treated tendons.

    Conclusion

    Increased levels of hydroxyproline and improved histopathological and biomechanical parameters in the treatment group suggest that blastema cells could be considered an adjunct to tendon repair in rabbits.

    Keywords: Cell-, Tissue-based therapy, Collagen, Ear Auricle, Hydroxyproline, Regenerative medicine, Tendons
  • Sreedhar Bodiga, Poorna Venkata Satya, Vijaya Lakshmi * Pages 20-29
    Objective(s)

    Dietary phytate is known to protect against azoxymethane (AOM)-induced preneoplastic lesions.  The present study was designed to determine whether dietary phytate affects mutation frequency in colon epithelial cells challenged with azoxymethane in vivo, through lowering the formation of O6-methyl guanosine (O6-MeG) and 8-hydroxy deoxyguanosine (8-OHdG) adducts.

    Materials and Methods

    We used Fisher F344 rats induced with AOM for 20 weeks and undertook 1% or 2% phytate supplementation for subsequent 16 weeks to monitor the mutation frequencies of one of the candidate genes, K-ras, along with DNA adduct load.

    Results

    Dietary phytate significantly suppressed aberrant crypt foci formation and effectively inhibited colon tumor formation in a dose-dependent manner. DNA sequencing results demonstrated that 60% of the colon tumors from AOM-treated and control diet fed animals showed GGT to GAT transition and 40% of the tumors showed GGT to GTT transversion at codon 12, along with 18% of the tumors showing GGC to CGC transversion at codon 13. Phytate supplementation at 1 and 2% lowered the frequency of GGT > GAT to 30 and 10%, respectively. Phytate supplementation also nullified the codon 13 mutations. No mutations were observed at codon 61 in any of the experimental groups.

    Conclusion

    The lowered frequency of K-ras mutations correlated with decreased formation of hydroxyl radicals, O5-meG and 8-OH-dG levels in phytate-supplemented animals with lowered tumor burden.

    Keywords: Azoxymethane, Colon, DNA adducts, Hydroxyl radical, Inositol hexaphosphate, K-ras
  • Zohreh Sadat Ghoreshi, Razieh Kabirifar, Ameneh Khodarahmi, Alireza Karimollah, Ali Moradi * Pages 30-35
    Objective(s)

    Atorvastatin is a cholesterol-lowering agent capable of inhibiting 3-hydroxy-3-methylglutaryl coenzyme A reductase. Recent studies have demonstrated new facets of atorvastatin, such as antioxidant and anti-fibrotic properties. We investigated the effect of atorvastatin on hepatic injury via the measurement of the antioxidant capacity and protein expression of NOX1, Rac1-GTP, and Rac1 in a rat biliary duct ligation (BDL) model.

    Materials and Methods

    This study is regarded as experimental interventional research in which a total of 32 adult male Wistar rats (200-250 g) were assigned to 4 groups (eight rats per group) as follows: Control group; Control + At group (15 mgkgday atorvastatin); BDL group, and BDL+ At group (15 mgkgday atorvastatin). Expression levels of Rac1, NOX1, and Rac1-GTP were determined by western blot analysis. Besides, specific biomarkers of oxidative stress in hepatic tissues of all animals were also analyzed.

    Results

    Atorvastatin reduced liver injury via a decrease in the expression of NOX1, Rac1-GTP, and Rac1 in the BDL group (P<0.05), while the increased contents of protein thiol groups were observed, and the protein carbonylation was decreased in atorvastatin-treated BDL rats compared to the BDL group (P<0.05). Also, administration of atorvastatin in the BDL group significantly lowered oxidative stress through increasing the activity of catalase and superoxide dismutase in comparison with the BDL group (P<0.05).

    Conclusion

    It seems that atorvastatin has potential advantages in mitigation of liver fibrosis by a decrease in the expression of NOX1, Rac1-GTP, and Rac1, along with, a reduction in oxidative stress of liver tissues in rats induced by BDL.

    Keywords: Atorvastatin, Biliary duct-ligation, Liver fibrosis, NOX1, Oxidative stress, Rac1, Rac1-GTP
  • Mohammad Chamani *, Hamid Reza Khodaei, Ali Asghar Sadeghi, Seyed Hossein Hejazi, Reza Majidzadeh, Faeze Fazel Pages 36-45
    Objective(s)

    Zinc is an effective factor in the reproductive system. Insulin resistance (IR) is known as an important disorder in patients with polycystic ovary syndrome (PCOS). Mammalian target of rapamycin (mTOR), which controls key cell activities, in particular, is activated in disorders such as PCOS. The present study was conducted to observe the therapeutic effects of organic zinc on IR, mTOR gene expression, and pathogenesis of PCOS in a rat model induced-PCOS.

    Materials and Methods

    Experimental treatments were performed on control and treated groups, consisting of healthy controls (Control, water, and standard feed intake and daily injection of sesame oil alone), Polycystic control (PCO, injection of 4 mg/kg estradiol valerate (EV) for four weeks). Treated groups (PCO-ZM 25, PCO-ZM 75, and PCO-ZM 175) after 4 weeks of receiving EV, were daily given three levels of 25, 75, and 175 mg zinc methionine/kg BW for 15 days, respectively.

    Results

    Injection of EV dramatically increased body and ovarian weights, levels of LH, testosterone, estradiol, triglyceride, fasting insulin, fasting glucose, HOMA-IR, IGF-1, gene expression of mTOR, and number of cysts (P<0.05). It also reduced the level of progesterone, HDL-C, and the number of antral follicles (P<0.05). However, by increasing zinc-methionine application especially at 175 mg/kg BW, the induction effects of EV were improved on ovarian cysts (P<0.05).

    Conclusion

    Organic zinc showed beneficial effects in the EV induced PCOS rats via decreased insulin resistance and mTOR expression, restored the hormonal profile, and decreased the number of cysts in the ovaries.

    Keywords: insulin resistance, mTOR, Polycystic ovary syndrome, Rat, Zinc-methionine
  • Yucel Duman *, Yasemin Ersoy, Nafia Gursoy, Baris Otlu, Sibel Altunisik Pages 46-50
    Objective(s)

    Infections due to carbapenemase-producing Klebsiella pneumoniae are associated with high morbidity and mortality. In this study, we report a hospital outbreak due to co-producing OXA-48 and NDM-1 K. pneumoniae clone. The aim of the study is to investigate the clonal relationship of strains, risk factors of outbreak and infection control measures.

    Materials and Methods

    Once an outbreak was suspected at the end of December 2017 in our intensive care unit (ICU), carbapenem resistance K. pneumoniae identified in patients’ specimens. An outbreak analysis was begun to determine the risk factors and dissemination of the cases. A case-control study was conducted to determine the risk factors. To control the outbreak; tight contact prevention, good clean-up the medical devices and hospital environment, were done. Staff training programs such as hand hygiene, disinfection, wearing aprons, good cleaning were created. Carbapenem resistance genes determined by PCR. Clonal relationships of strains investigated by PFGE.

    Results

    We investigate 21 carbapenem-resistant K. pneumonia strains. Nine of them were found co-produced NDM-1 and OXA-48, 11 strains produced OXA-48, and one strain produced NDM-1. Seven strains of co-producing NDM-1 and OXA-48 were found clonally related with PFGE. We could not determine any risk factor except rectal colonization in the case-control study.

    Conclusion

    The interventions that successfully controlled this outbreak were hand hygiene, tight contact prevention, good clean-up of the hospital environment and medical devices. As a result, we believe that it would be beneficial to take infection control measures to prevent the spread of these strains to the community and hospital settings.

    Keywords: Carbapenemase, Klebsiella pneumoniae, NDM, OXA-48, Outbreak
  • Alireza Rezaee Khorasany, Marjan Razavi, Elahe Taghiabadi, Hossein Hosseinzadeh *, Abbass Tabatabaee Pages 51-62
    Objective(s)

    The drinking of ethanol causes the wide range of clinical illness and morphological changes including hepatotoxicity and nephrotoxicity. In the current study, the protective properties of crocin versus oxidative stress, apoptosis and inflammation induced by ethanol were assessed.

    Materials and Methods

    The male Wistar rats were divided into seven groups consisting of 6 rats in control, ethanol (50% v/v - 5 g/kg), crocin (10, 20 and 40 mg/Kg) plus ethanol, crocin 20 and 40 mg/Kg.

    Results

    The MDA level was remarkably enhanced, while the content of GSH was significantly diminished in the kidney and liver of alcoholic rat but protective groups restored the level of MDA and GSH contents. Ethanol consumption induced hepatotoxicity and nephrotoxicity as evidenced by biochemical abnormalities and histopathological damages but crocin improved them. Also, crocin restored the TNF-α and IL-6 levels in the liver. The consumption of ethanol enhanced the levels of caspase-3, -8, -9 and Bax/Bcl-2 ratio (mRNA and protein) but, western blot and real-time PCR data confirmed that crocin treatment prevented apoptosis induced by ethanol.

    Conclusion

    This research demonstrates that crocin has protective activities against ethanol toxic effects in rat liver and kidney via anti-inflammatory, antioxidant, and anti-apoptotic effects.

    Keywords: Crocin, Ethanol, Hepatotoxicity Nephrotoxicity, Oxidative stress
  • Tahereh Ghadiri *, Ali Gorji, Gelareh Vakilzadeh, Vahid Hajali, Fariba Khodagholi, Mohammad Sharifzadeh Pages 63-70
    Objective(s)
    While traumatic brain injury (TBI) is a predisposing factor for development of post-traumatic epilepsy (PTE), the occurrence of seizures following brain trauma can infuriate adverse consequences of brain injury. However, the effect of seizures in epileptogenesis after mild TBI cannot yet be accurately confirmed. This study was designed to investigate the histopathological and molecular modifications induced by seizures on traumatized brain.
    Materials and Methods
    Using a new method, head was traumatized and seizures were evoked by sub-convulsive dose of pentylenetetrazole (PTZ) fifteen days after induction of focal mild TBI. Convulsion assessments were performed one hour after PTZ injection and was followed by histopathological and molecular evaluations.
    Results
    A significantly higher score and longer duration of seizure attacks as well as higher number of epileptiform discharges were observed in the TBI+PTZ group compared to sham and TBI groups. An elevated number of apoptotic cells was observed in the TBI+PTZ group compared to sham and TBI rats. Molecular investigations revealed higher levels of Bax/Bcl2 ratio, Caspase 3, and NF-κB in the TBI+PTZ group compared to the other animal groups. The value of Nrf2 did not change after mild TBI compared to sham and PTZ control groups. Occurrence of seizures after TBI, however, significantly decreased the level of Nrf2.
    Conclusion
    Our data indicated that seizure occurrence following mild TBI aggravates cell injury and death via activation of neuroinflammatory processes and may increase the risk of PTE. Additionally, our results suggest a potential protective role of Nrf2 after chemically evoked PTE.
    Keywords: Apoptosis, Convulsive, Hippocampus, Neuroinflammation, Post-traumatic, Seizure
  • Aydan Özgörgülü, SEDA Cetinkaya * Pages 71-78
    Objective(s)

    Resveratrol (RSV) is a naturally occurring plant polyphenol with cardioprotective, neuroprotective, immunoregulatory, and anticancer properties and is biologically effective against various diseases. This study aimed to investigate the chemopreventive effect of different doses of RSV against hepatocellular carcinoma (HCC) induced by  diethylnitrosamine (DEN) in rats.

    Materials and Methods

    The rats were randomly divided into  six groups of seven  rats each  (n=42). The control group (group 1) was injected with saline, group 2 with dimethyl sulfoxide (DMSO), group 3 with DEN, group 4 with DEN and 50 mg/kg of RSV (DEN+RSV 50), group 5 with DEN and 75 mg/kg of RSV (DEN+RSV 75), and group 6 with DEN and 100 mg/kg of RSV (DEN+RSV 100). Pro-apoptotic Bax/anti-apoptotic Bcl-2 and tumor suppressor p53 markers were analyzed by immunostaining.

    Results

    Superoxide dismutase, glutathione, and malondialdehyde concentrations were not statistically significant in DEN+RSV 100 group but were closest to the concentrations in control group. Liver function tests showed that enzyme activity (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transferase) increased in DEN+RSV 50 and DEN+RSV 100 groups compared with control group but decreased in DEN+RSV 50 and DEN+RSV 100 groups compared with DEN group. Bax/Bcl-2 and p53 analysis showed a statistically significant increase in apoptotic cells in DEN+RSV 100 group.

    Conclusion

    A 100 mg/kg dose of RSV may be a promising treatment for HCC.

    Keywords: Apoptosis, Diethylnitrosamine, Hepatocellular carcinoma, In vivo, Resveratrol
  • Parisa Habibi, Alireza Alihemmati, Nasser Ahmadiasl, Abolfazl Fateh, Enaiat Anvari * Pages 79-85
    Objective(s)
    The useful and effective role of exercise program to prevent cardiac tissue apoptosis and fibrosis in ovariectomized type 2 diabetic (T2DM) rats (OVR.D) is well known. The current study aimed to investigate the simultaneous effects of T2DM and swimming plan on the expression of some apoptotic, anti-apoptotic biomarkers and glycogen changes in the cardiac muscle tissue of ovariectomized (OVR) rats.
    Materials and Methods
    Forty rats were randomly sorted into 4 equal categories; sham, OVR, OVR.D and diabetic ovariectomized with an 8 week of swimming plan (OVR.D.E). Lipid profile and miR-133, Bcl-2, Bax, caspase-3 and caspase-8 levels were evaluated in the cardiac tissue.
    Results
    Ovariectomy significantly (P-value<0.05) increased cholesterol, triglyceride, LDL, Bax, caspase-3, caspase-8 and decreased (P-value<0.05) HDL, miR-133, Bcl-2 in the cardiac tissue and a further reduction in the expression of miR-133, Bcl-2 and an enhancement in Bax, caspase-3 and caspase-8 in OVR.D rats was observed (P-value<0.01). However, exercise training significantly reversed all the measured parameters (P-value<0.05). Also, exercise training improved abnormal tissue structure, fragmentation and irregular form of glycogen granules in the OVR.D.E compared to OVR and OVR.D animals.
    Conclusion
    Exercise training could prevent the cardiac disturbance, enhance the expression of anti-apoptotic markers and decrease apoptotic biomarkers in the hearts of OVR.D animals. Therefore, based on the findings of this study suggested using the exercise’s beneficial effects for prevention of the cardiac cell death in OVR.D animals.
    Keywords: Apoptosis regulatory-proteins, Caspase-3, Caspase-8, Diabetes Mellitus, microRNAs, Type 2
  • Mehrdad Jahanshahi *, Emsehgol Nikmahzar, Ali Sayyahi Pages 86-92
    Objective(s)
    Vitamin E may have beneficial effects on oxidative stress and Aβ-associated reactive oxygen species production in Alzheimer’s disease. But, the exact role of vitamin E as a treatment for Alzheimer’s disease pathogenesis still needs to be studied. Hence, we examined the therapeutic effects of vitamin E on the density of congophilic amyloid plaques and neurofibrillary tangles in rats’ hippocampi.
    Materials and Methods
    Wistar rats were randomly assigned to control (no drug treatment), sham scopolamine (3 mg/kg)+saline and Sham scopolamine+sesame oil groups, and three experimental groups that received scopolamine+vitamin E (25, 50, and 100 mg/kg/day) daily for 14 days after scopolamine injection. The rats’ brains were collected immediately following transcardial perfusion and fixed in 4% paraformaldehyde. Pathological brain alterations were monitored through Congo red and bielschowsky silver staining.
    Results
    Scopolamine treatment led to a significant increase in the density of congophilic amyloid plaques and neurofibrillary tangles in the hippocampus. IP injection of vitamin E in three doses (25, 50, and 100 mg/kg/day) significantly reversed the scopolamine-induced increase of the congophilic amyloid plaque density and density of neurofibrillary tangles in the hippocampus. Although vitamin E (25 and 50 mg/kg/day) doses were also effective, but a 100 mg/kg/day dose of vitamin E was more effective in the reduction of congophilic amyloid plaque and neurofibrillary tangle density.
    Conclusion
    Vitamin E could exert a therapeutic effect in the reduction of congophilic amyloid plaque and neurofibrillary tangle density in the hippocampus of scopolamine-treated rats and it is useful for Alzheimer’s disease.
    Keywords: Amyloid plaque, Hippocampus, Neurofibrillary Tangles, Rat, Vitamin E
  • Christian De Jesús Rosas, Eduardo Rivadeneyra, Bertha Alicia León, Rasajna Nadella, Aurora Del Carmen Sánchez, Daniel Rembao, Juan Francisco Rodríguez, Daniel Hernandez Baltazar * Pages 93-101
    Objective(s)

    Cassava (Manihot esculenta Crantz) contains cyanogenic glycosides (linamarin and lotaustralin) that have been associated with neurological disorders in humans and rats. In basal ganglia, the dopaminergic neurons of substantia nigra pars compacta (SNpc) show high cytotoxic susceptibility; therefore, the chronic consumption of cassava (CCC) could induce neurodegeneration in SNpc.  In this study we examine the impact of CCC on the integrity of the nigrostriatal system, including apoptosis and microgliosis.

    Materials and Methods

    Male Wistar rats were administered cassava juice daily (3.57 g/kg and 28.56 g/kg, per os) or linamarin (0.15  mg/ml, IP), and its effects were evaluated in rota-rod and swim tests at days 7, 14, 21, 28, and 35 of administration. In SNpc, oxidative/nitrosative stress was determined by malondialdehyde/4-hydroxyalkenals (MDA-4-HAD) and nitrite contents. Tyrosine hydroxylase immunoreactivity (TH-IR) was evaluated in SNpc, neostriatum (NE), and nucleus accumbens (NA). Apoptosis and microgliosis were determined by active-caspase-3 (C3) and CD11b/c (OX42) expression in the medial region of SNpc.

    Results

    Chronic administration of cassava juice, or linamarin, increased motor impairment. The rats that received 28.56 g/kg cassava showed increased MDA-4-HAD content in SNpc and nitrite levels in NE with respect to controls. Significant loss of TH-IR in SNpc, NE, and NA was not found. The 28.56 g/kg cassava administration produced dopaminergic atrophy and microgliosis, whereas linamarin induced hypertrophy and C3-related apoptosis in SNpc.

    Conclusion

    CCC induces cellular stress on dopaminergic neurons, which could contribute to motor impairment in the rat.

    Keywords: Apoptosis, Inflammation, Hypertrophy, Manihot, Survival
  • Shayan Vafaei, Fatemeh Motejaded, Alireza Ebrahimzadeh* Pages 102-110
    Objective(s)

    Exposure to electromagnetic fields (EMF) emitted from mobile phones may cause a deleterious effect on human health and may affect the male reproductive system. Crocin, a carotenoid isolated from Crocus Sativus L. (Saffron), is a pharmacologically active component of saffron. So, this study was conducted to investigate the protective effect of crocin on the male reproductive system of 60 day old mice after EMF exposure.

    Materials and Methods

    Twenty-four male Balb/c mice were randomly divided into 4 groups: 1. Em group (2100 MHZ); 2. Cr group (50 mg/kg); 3. Em+Cr group (2100 MHZ+50 mg/kg), and 4. Control group. Sperm parameters (count, and abnormal percent), testis weight index, testis volume, seminiferous tubule diameter, germinal epithelium thickness, LH, FSH and testosterone serum level, testicular Heat shock protein A2 (HspA2) immunoreactivity, and apoptosis were evaluated.

    Results

    HspA2 immunoreactivity, apoptosis in the germinal epithelium and abnormal sperm were increased in Em group compared with the control group (P<0.05). Sperm count, LH, and testosterone serum level were decreased in the Em group compared with the control group (P<0.05). These parameters were improved in the Em+Cr group compared with Em group significantly (P<0.05).

    Conclusion

    our findings revealed that EMF exposure leads to harmful impressions on the male reproductive system, while crocin can attenuate EMF-induced destructive effects.

    Keywords: Electromagnetic Field, Crocin, Testis, Apoptosis, Heat Shock Protein
  • Sakshi Tyagi, Simranjot Kaur, Nirmal Singh, Amteshwar Jaggi * Pages 111-116
    Objective(s)
    To study the effect of acute and repeated stress on cardioprotection-induced by remote ischemic preconditioning (RIPC).
    Materials and Methods
    RIPC was induced by giving 4 short cycles of ischemia and reperfusion, each consisting of five min. The Langendorff’s apparatus was used to perfuse the isolated rat hearts by subjecting the hearts to global ischemia of 30 min and reperfusion of 120 min. The coronary effluent was collected to measure the levels of lactate dehydrogenase (LDH) and creatine kinase (CK) for the assessment of injury to the myocardium. Myocardial infarct size was measured by the use of triphenyl tetrazolium chloride. Acute stress was induced by subjecting the animals to cold immersion stress for 5 min. However, in the case of stress adaptation, rats were exposed to a homotypic stressor (cold-water immersion stress) each of 5 min duration for five consecutive days.
    Results
    RIPC demonstrated a significant decrease in ischemia-reperfusion-induced myocardial injury in terms of decrease in LDH, CK, and infarct size. However, acute stress for five minutes prior to RIPC significantly abolished its cardioprotective effects. Exogenous administration of adenosine restored RIPC-induced cardioprotective effects in the presence of acute stress. On repeated stress exposure for 5 days, stress adaptation was noted, and there was no effect of repeated stress exposure on RIPC-induced cardioprotection. However, the cardioprotective effects of adenosine were absent in the case of rats subjected to repeated episodes of stress.
    Conclusion
    Acute stress, but not repeated stress exposure, may alter the release of adenosine during RIPC, which may be manifested in the form of reduced cardioprotection during ischemic-reperfusion injury.
    Keywords: Acute stress, Adaptation, Cardioprotection, Cold-water immersion, Remote ischemic preconditioning
  • Hoda Nadimi, Abolghassem Djazayery, Mohammad Hassan Javanbakht, Ahmadreza Dehpour, Ehsan Ghaedi, Hoda Derakhshanian, Hamed Mohammadi, Seyedeh Neda Mousavi, Mahmoud Djalali * Pages 117-123
    Objective(s)
    Cyclic AMP (adenosine monophosphate) response element-binding protein (CREB) and Brain-derived neurotrophic factor (BDNF) are reported to broadly involve in learning capacity and memory. BDNF exerts its functions via tropomyosin receptor kinase B (TrkB). BDNF transcription is regulated by stimulating CREB phosphorylation. The CREB-TrkB-BDNF pathway is reported to be affected by diabetes, which may contribute to its cognitive deficits. This study was conducted to investigate the effect of vitamin D supplementation on the hippocampal fraction of this pathway in an animal model of type-1 diabetes mellitus (T1DM).
    Materials and Methods
    Thirty-six adult male Sprague-Dawley rats were randomly divided into 4 groups as follows: Group 1: normal healthy rats (n=8); group 2: normal healthy rats receiving sesame oil supplementation as placebo (n=8); Group 3: diabetic rats receiving sesame oil (n=10); and Group 4: diabetic rats treated with 4300 IU/kg/week vitamin D dissolved in sesame oil (n=10). Diabetes was induced by intraperitoneal (IP) injection of streptozotocin. Blood and hippocampal samples were acquired at the end of the experiment. RNA was extracted from the hippocampus, and real-time PCR (polymerase chain reaction) was performed for BDNF and TrkB gene expression.
    Results
    Administration of vitamin D (4300 IU/kg/week) in a T1DM animal model increased CREB phosphorylation in the hippocampus, but the serum and hippocampal BDNF levels and TrkB and BDNF gene expression did not change significantly.
    Conclusion
    Vitamin D increased hippocampal CREB phosphorylation in a T1DM animal model. Our findings showed that vitamin D might be protective against central nervous system complications in diabetes. However, future studies are warranted.
    Keywords: Brain-derived neurotrophic factor, CREB, Diabetes, TrkB, Vitamin D
  • Erkan Maytalman, Ilknur Kozanoglu, Menderes Yusuf Terzi, Fazilet Aksu, Arash Alizadeh * Pages 124-132
    Objective(s)

    Cells perform their functional activities by communicating with each other through endogenous substances and receptors. Post-translation, stem cells function properly in new host tissue by carrying specific cell surface receptors. We aimed to characterize muscarinic receptor subtypes in mesenchymal stem cells (MSCs) together with osteogenic and adipogenic differentiation markers.

    Materials and Methods

    mRNA levels of 5 muscarinic receptor subtypes (CHRM1 to 5), BMP-6, and PPARγ during osteogenic and adipogenic differentiation, under the effect of atropine blockade, were measured in MSCs obtained from human fetal membrane (FM) and bone marrow (BM). Additionally, the effect of atropine on differentiation in the 1st, 2nd, and 3rd passages of MSCs, obtained from human FM and BM, were analyzed by RT-qPCR.

    Results

    CHRM1 mRNA levels increased in the FM group, while decreasing in the BM group. We found significant decreases in CHRM3 and CHRM5 mRNA levels in FM and BM groups, respectively. Atropine had variable effects based on cell source and receptor type. BMP-6 mRNA levels in differentiated osteogenic cells increased significantly compared to undifferentiated cells in both FM and BM groups. In MSCs derived from both sources, PPARγ mRNA levels in differentiated adipogenic cells increased significantly. Atropine showed no effect on MSCs differentiation.

    Conclusion

    These results indicate that expressions of muscarinic receptors in MSCs derived from BM and FM can vary and these cells keep the potential of osteogenic and adipogenic differentiation in vitro. Besides, atropine had no effect on adipogenic and osteogenic differentiation of MSCs.

    Keywords: Atropine, bone marrow, Cell differentiation, Gene expression, Human placenta, Mesenchymal stem cells, Muscarinic receptors
  • Rao Muhammad Abid Khan, Sana Anwar, Zaid Ahmed Pirzada * Pages 133-139
    Objective(s)

    Streptococcus pyogenes, a notorious human pathogen is responsible to cause a wide range of infections varies from superficial common clinical illness to severe and life threatening infections. To our knowledge this is the first report exploring the emm types and superantigen/exotoxin gene profile of S. pyogenes from Pakistan.

    Materials and Methods

    A total of 89 S. pyogenes strains were collected predominantly from throat swabs followed by pus, tissues and wound swabs. Profile of five superantigen genes speA, speB, speC, speF and ssa was screened for all the emm types.

    Results

    Extensive heterogeneity among S. pyogenes strains was indicated, revealing 34 different emm types/ subtypes. The most prevalent emm types were emm68 and emm104. Some of the emm types were exclusively isolated from invasive infections while others were isolated only from non-invasive infections indicating the possible link between emm types and invasive/ noninvasive infections. Similarly, erythromycin-resistant strains mainly belonged to three particular emm types. Multiplex PCR analysis indicated the presence of speB 100%, speF 76%, speC 20%, speA 18% and ssa 15%. Interestingly, superantigen genes speC and speA were mainly associated with invasive infections. Among the five superantigens tested, one strain of emm12 harbored all the analyzed exotoxin genes, while 4 strains carried 4 superantigen genes.

    Conclusion

    S. pyogenes clones associated with invasive and non-invasive infections in Pakistan present differences in emm types, superantigens and antimicrobial resistance. The present data indicates the possible link between particular genetic lineage of a bacterium with the manifestation of the infection.

    Keywords: Gas, Exotoxin, Invasive pathogens, Antibiotic resistance, MIC