Iranian Journal of Basic Medical Sciences
Volume:22 Issue: 12, Dec 2019

This paper reviews the potential role of honey as a therapeutic antioxidant to reduce oxidative stress and improve cognitive ageing. All articles indexed to PubMed Central (PMC) were searched using the following key words: honey, antioxidant, memory and ageing. Honey is a natural insect-derived product with therapeutic, medicinal and nutritional values. Antioxidant properties of honey quench biologically-circulating reactive oxygen species (ROS) and counter oxidative stress while restoring the cellular antioxidant defense system. Antioxidant properties of honey may complement its nootropic effects to reduce cognitive ageing.

One of the common heterogeneous reproductive disorders in women of childbearing age is polycystic ovary syndrome (PCOS). It is characterized by lack of fertility due to anovulatory cycles, hyperandrogenemia, polycystic ovaries, hyperinsulinemia, and obesity. Both reproductive anomalies and metabolic disorders are involved in PCOS pathology. Although the role of increased levels of androgens in initiation of PCOS is almost proven, mechanisms of PCOS pathophysiology are not clear. Here we discuss roles of altered metabolic conditions, obesity, and chronic inflammation in PCOS pathophysiology.

In this review, we attempted to identify genes related to obesity and chronic inflammation aspects of PCOS and their physiological functions to explain the pathways that are regulated by these genes and can be a prominent function in PCOS predisposition. For this purpose, published articles and reviews dealing with genetic evaluation of PCOS in women in peer-reviewed journals in PubMed and Google Scholar databases were included in this review.

Obesity and chronic inflammation are not prominent diagnostic features of PCOS, but they play an important role in exacerbating metabolic and hyperandrogenic states. ADIPOQ, FTO TGFβ, and DENND1A as the main obesity- and chronic inflammation-related genes have roles in PCOS pathophysiology.

It seems that genes related to obesity pathology in genomic research association, are related to metabolic aspects and body mass index in PCOS patients. Genomes have roles in chronic inflammation, followed by obesity, in the pathogenesis of PCOS.

Plasmid-mediated quinolone resistance (PMQR) determinants and integrons have a considerable contribution to bacterial drug resistance in Gram-negative pathogens. We studied the prevalence of PMQR genes and integron carriage in multidrug-resistant community isolates of Klebsiella spp. Two hundred and fifty Klebsiella spp. isolates were collected from outpatient specimens between August 2015 and October 2017 in Yazd central Laboratory, Iran. Antibiotic susceptibility was determined against 17 antibiotics and minimum inhibitory concentration (MIC) of ciprofloxacin was measured by E-test. Polymerase chain reaction (PCR) was employed for detection of qnrA, qnrB, qnrS, aac(6’)-Ib-cr, oqxAB and qepA genes. Disc diffusion results showed that 17 isolates (6.8%) were multidrug resistant (MDR), two of which were Klebsiella oxytoca and 15 were Klebsiella pneumoniae. MIC measurements revealed 11 ciprofloxacin-resistant isolates (including the two K. oxytoca), three intermediately-resistant and three ciprofloxacin-susceptible isolates. All ciprofloxacin-resistant and intermediately-resistant isolates carried at least one and up to four PMQR genes. The most prevalent PMQR gene was oqxAB (93.75%) followed by aac(6’)-ib-cr (50.0%), qnrB (25.0%) and qnrS (18.75%) but qnrA and qepA were not detected. Class 1 integron was observed in 14 (82.3%) isolates including nine ciprofloxacin-resistant, two intermediately-resistant, and three susceptible isolates. Class 2 and 3 integrons were not observed. Presence of MDR, multiple PMQR determinants as well as class 1 integron in community isolates of Klebsiella spp. can be an important source of transmission of these opportunistic pathogens.

Varenicline is a selective partial agonist for the nicotinic acetylcholine receptor a4b2 subtype, which is widely used to treat smoking addiction. However, there is still no data about its potential toxic effects on tissues. In this study, we aimed to determine the varenicline-induced toxicity on reproductive and renal tissues in rats.

Rats were randomly divided into two groups: control (n=10) and varenicline (n=24). Then, rats in each group were sub-divided equally as acute and chronic groups. The control rats were orally given distilled water only. Varenicline was administrated orally as follows: 1st–3rd days 9 µg/kg/day, 4th–7th days 9 µg/kg twice daily, and 8th–90th days 18 µg/kg twice daily. The rats of acute and chronic groups were sacrificed on the 45th and 90th days, respectively. Some tissue markers related to oxidative stress were measured, and sperm characteristics were observed.

In the acute group, varenicline led to a significant decrease in SOD activities in both kidney and testis tissues. In the chronic group, varenicline significantly increased MDA and MPO production, and reduced CAT and GPx levels in the kidneys and testes. Also, SOD and GSH levels significantly decreased in the testes. Moreover, sperm characteristics were negatively affected; histopathological deformation was observed in the testes and kidneys in all groups.

This study showed that varenicline could detrimentally affect the kidneys and testes in both acute and chronic term usage. Further studies will provide more insights into the molecular dynamics of this damage.

Hepatic ischemia/reperfusion injury (IRI) is one of the major causes of hepatic failure during liver transplantation, trauma, and infections. The present study investigated the protective effect of intra-portal administration of 2-methoxycinnamaldehyde (2-MCA) on hepatic IRI in rats. Twenty-four rats were equally divided into four groups; 1) sham group, (no IRI or transfusion), 2) Hepatic IRI (60 min ischemia + 120 min reperfusion, 3) Hepatic IRI+ NS (IRI + normal saline), 4) Hepatic IRI+2-MCA, (IRI + 2-MCA). In groups 3 and 4, 1 ml/kg normal saline and 2-MCA were administered slowly into the vein of the left lateral and median lobes of the liver 10 min before induction of hepatic reperfusion (upper the site of clumping), respectively. The harvest time points were at 2 hours post-reperfusion in all groups. Histologically, cell death, degenerative changes, sinusoidal dilatation, congestion, hemorrhage, and infiltration of inflammatory cells were observed in IRI group, while these pathological changes were attenuated in the 2-MCA administrated group. The level of alanine transaminase, aspartate transaminase, tumor necrosis factor- α and interleukin-6 in serum and hepatic malondialdehyde were significantly increased by IRI, and 2-MCA administration reduced all these markers. In addition, caspase-3 and nuclear factor κB (NF-κB) expression were investigated immunohistochemically. Administration of 2-MCA considerably decreased caspase-3 positive cells and NF-κB activity in comparison with IRI group. As a conclusion, in situ administration of 2-MCA protects against hepatic IRI via anti-inflammatory, and anti-apoptotic properties.

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex proteins are involved in membrane trafficking. The expression of isoforms of SNAP-23, syntaxin-4, and VAMP-2 is significantly done in skeletal muscles; they control GLUT4 trafficking. It is believed that type 2 diabetes could be caused by the modifications in the expression of SNARE complex proteins. The purpose of this study was to evaluate the effect of resveratrol on the expression of these proteins in type 2 diabetes.

Forty male Wistar rats were selected. Streptozotocin and nicotinamide were applied for the induction of type 2 diabetes. The animals were divided into five groups. Healthy and diabetic groups were set as control; resveratrol (1, 5, and 10 mg/kg body weight) was applied to treat the three groups of diabetic rats for 30 days. Real-time qRT-PCR was applied to evaluate the expression of SNARE complex proteins.

There is a link between diabetes and insulin resistance and up-regulation of SNARE proteins expression. Resveratrol improved hyperglycemia and insulin resistance along with a non-significant reduction in the expression of SNARE proteins.

Increased expression of SNARE proteins was possibly a compensatory mechanism in response to insulin resistance in the skeletal muscles of diabetic rats. Resveratrol non-significantly reduced the expression of SNARE proteins by enhancing insulin sensitivity, where this effect was dose-dependent. Thus, higher doses of resveratrol and longer intervention periods could probably be more effective. Another molecular mechanism of the anti-diabetic properties of resveratrol was identified with an effect on the expression of SNARE proteins.

Reperfusion of ischaemic myocardium results in reduced nitric oxide (NO) biosynthesis by endothelial nitric oxide synthase (eNOS) leading to endothelial dysfunction and subsequent tissue damage. Impaired NO biosynthesis may be partly due to increased levels of asymmetrical dimethylarginine (ADMA), an endogenous inhibitor of eNOS. As dimethylarginine dimethylaminohydrolase (DDAH) is a key enzyme responsible for degradation of ADMA, the present study was designed to explore the role of DDAH/ADMA/NO pathway in cardio-protective mechanism of ischaemic postconditioning. Isolated rat hearts were subjected to myocardial ischaemia for 30 min followed by reperfusion for 2 hours in control group. Myocardial injury was assessed by measurement of infarct size, left ventricular developed pressure (LVDP), lactate dehydrogenase (LDH) and creatine kinase (CK) enzymes in coronary effluents. The reperfused hearts were homogenised and tissue concentration of nitrite, ADMA level and DDAH enzyme activity was determined. A significant increase in infarct size, LDH, CK release in coronary effluents and ADMA level in myocardial tissue was observed in control group. The increase in tissue ADMA coincided with reductions of NO tissue concentrations and DDAH activity. Ischaemic postconditioning significantly attenuated ischaemia-reperfusion induced myocardial injury manifested in the terms of decreased infarct size, LDH, CK, tissue ADMA along with increase in NO levels and DDAH enzyme activity. Pretreatment with L-Homocysteine (300 µM), a competitive inhibitor of DDAH, and L-NG-nitroarginine methyl ester (L-NAME; 100 µM), an inhibitor of eNOS, completely abolished ischaemic postconditioning-induced myocardial protection. Enhancing DDAH activity by postconditioning may be a novel target to reduce ADMA level and increase NO bioavailability to prevent myocardial ischaemia-reperfusion injury.

The present study evaluates the protective effects of myricitrin and its solid lipid nanoparticle (SLN) on diabetic nephropathy (DN) induced by streptozotocin-nicotinamide (STZ-NA) in mice. In this experimental study, 108 adult male NMRI mice were divided into 9 groups: control, vehicle, diabetes, diabetes + myricitrin 1, 3, and 10 mg/kg and, diabetes + SLN containing myricitrin 1, 3, and 10 mg/kg. After the experimental period, the plasma and tissue samples were collected for experimental, histopathological, real-time PCR and apoptosis assessments. Total antioxidant capacity, catalase, glomerular filtration rate, plasma level of albumin, urine (BUN) and, creatinine (Cr) levels decreased, and the kidney weight, intake/output, malondialdehyde, plasma level of BUN and Cr, urine level of sodium, potassium, albumin and glucose, fractional excretions of sodium and potassium, transforming growth factor-β (TGF-β) and nuclear factor kappa B (NF-κB) gene expression, red blood cell accumulation and infiltration of inflammatory cells, and kidney apoptosis increased in untreated diabetic mice compared to the control group, and administration of myricitrin and its SLN recovered all of these changes. Ultimately, myricitrin and its SLN administration improved DN changes by reducing oxidative stress and increasing antioxidant enzymes level, and these effects were more prominent in the SLN-administered mice.

This study aimed to show the effects of thymoquinone, which is known for its antioxidant, anti-inflammatory, and renal protective effects in contrast-induced nephropathy.

This is an experimental study in rats. 7 groups were included within the scope of our study: sham-vehicle (n=3), premedication-control (n=6), model (n=6), isolated thymoquinone (n=3+3), low-dose thymoquinone (n=6), and high-dose thymoquinone (n=7). In addition to 48 hr of water deprivation, we pre-medicated the rats with intra-peritoneal indomethacin and L-NAME administration. After premedication, 12.5 ml/kg dose of a high osmolar contrast agent-diatrizoat (Urografin %76) was administrated. Thymoquinone was administrated in two different doses of 1 mg/kg and 1.75 mg/kg for four days intraperitoneally. Renal functions, histopathological differences, oxidative stress parameters, and inflammatory indicators of rats were evaluated at the end of the study.

Significant decreases were observed in levels of serum creatinine and serum BUN with low-dose thymoquinone (1 mg/kg) administration. In light microscopy, significantly less histopathological damage was observed in the low-dose thymoquinone group compared to the contrast agent group. While high-dose thymoquinone is accepted as ineffective biochemically, toxic evidence was identified histopathologically. There were no significant differences between M and TA groups for serum MDA and SOD levels, which were compared to evaluate oxidative stress (P:0.99, P:0.98; respectively). TNF-α, iNOS, and NF-кB gene expressions were not significantly different between all groups (P:0.748, P:0.531, P:0.910; respectively).

This experimental study has demonstrated for the first time the protective effect of the TQ substance for CIN in 1 mg/kg dose, in the accompaniment of biochemical and histopathological data in rats.

In this study, the neutralizing abilities of the equine and the recently introduced camelid antivenoms on the hemodynamic parameters (inotropism, chronotropism, and arrhythmogenicity) were assessed following envenomation by Hemiscorpius lepturus venom in rats. At first, the electrophoretic profiles of both products were obtained by using the SDS-PAGE method (12.5%) and stained with Coomassie blue and silver nitrate. Secondly, different doses of the camelid antivenom (10, 50, and 100 µl) were given intravenously in 10 min before venom injection (400 µg/rat). The neutralizing potencies of camelid and equine antivenoms were measured by preincubation (100 µl) with H. lepturus venom for 30 min at room temperature. Finally, equal amounts of the antivenoms were injected intravenously to observe the hemodynamic changes. Based on the electrophoretic profile, it was evident that undesired proteins significantly decreased in equine antivenom, owing to impurities. Pretreatment with the camelid antivenom (100 µl), neutralized the elevation of the mean arterial pressure evoked with scorpion venom injection (88.15±4.56 versus 10.2±1.23 percent at the 8th min). The Incubation of the venom and the camelid antivenom counteracted the hemodynamic changes, but the equine product had no effect. The intravascular injection of the equine antivenom transiently increased the mean arterial pressure as compared to the control (108.67±8.63 mmHg versus 52.67±1.93 mmHg at the 10th min). The most obvious finding emerging from this study was that the camelid antivenom neutralized the hemodynamic changes in rats significantly, but in comparison, the equine antivenom had just a minor ability.

Neuropathic pain is a prevalent and debilitating neurological disorder. Ample evidence indicates that microglial cells and inflammatory cytokines are involved in the pathogenesis of neuropathic pain. Alpha-terpineol is a monoterpenoid alcohol with inhibitory effect on inflammatory cytokines. The main purpose of this study was to evaluate the effect of α-terpineol on neuropathic pain in rats. Chronic constriction injury (CCI) model was utilized to induce neuropathic pain in male Wistar rats. The rats were randomly divided into control, sham, α-terpineol, and gabapentin groups. Normal saline, α-terpineol (25, 50, and 100 mg/kg), and gabapentin (100 mg/kg) were administered intraperitoneally in the above-mentioned groups once daily for 14 days post-CCI. Behavioral tests, including Von Frey, acetone, and Hargreaves were used to assess mechanical allodynia, cold allodynia, and hyperalgesia in rats. Iba1 immunostaining and ELISA procedures were used to assess the activation of microglial cells and inflammatory cytokines level. The results showed that α-terpineol (50 and 100 mg/kg) significantly attenuated mechanical allodynia, cold allodynia, and hyperalgesia in the neuropathic rats. The analgesic effect of α-terpineol (100 mg/kg) was comparable with that of gabapentin as a standard antineuropathic pain drug. In addition, α-terpineol (25, 50 and 100 mg/kg) significantly decreased the number of Iba1-positive cells and diminished the concentration of IL-1β and TNF-α in the spinal tissue. It was ultimately attained that α-terpineol attenuates neuropathic pain through the suppression of the microglial cells and reduction of inflammatory cytokine levels in the spinal cord of rats.

This study is aimed to design and synthesize a prodrug of 5-aminosalicylic acid and evaluate its ameliorative effect on experimental ulcerative colitis (UC). 5-Aminosalicylic acid-alanine (5-ASA-ALA) was synthesized and characterized. Its stability study was conducted in rat plasma and in the gastrointestinal tract environment, its transport characteristic was assessed using the Caco-2 cells. Its colon-targeting property was evaluated by the pharmacokinetic study, and incubation studies. A series of indicators were used to investigate its therapeutic effect on experimental colitis, including the survival rate and body weight of mice, the disease activity index (DAI), the colonic damage score and colon index, the myeloperoxidase (MPO) activity and the levels of malondialdehyde (MDA), total superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px) in colonic tissues. 5-ASA-ALA was barely absorbed in the Caco-2 monolayer or into the rat blood. It was remarkably stable when incubated in the upper gastrointestinal tract, while gradually hydrolyzed in the colon of rats. When orally administered to mice, 5-ASA-ALA had significantly greater therapeutic effect on colitis than the positive control.   5-ASA-ALA is demonstrated to be a promising oral colon-targeting prodrug of 5-ASA and has potential application in UC treatment.

Kisspeptin and opioids are important factors for controlling GnRH/LH secretion. In present study, influences of kisspeptin or morphine were investigated on 5α- reductase or aromatase (CYP19) genes expression in the hypothalamus, testis and liver. It aimed to investigate whether kisspeptin pathway may control morphine effects on plasma concentration of testosterone. Twenty adult male rats in four groups received saline/saline, kisspeptin (1 nmol)/saline, morphine (5 mg/kg)/saline or kisspeptin/morphine respectively. Mean relative 5α-reductase and aromatase mRNA levels were determined by RT-PCR. Morphine/saline injection increased significantly mean relative mRNA levels of hypothalamic 5α-reductase or aromatase compared to saline/saline. While morphine/saline did not alter mRNA levels of them compared to saline/saline group in the testis and liver. Kisspeptin/saline did not significantly decrease mean relative 5α-reductase or aromatase genes expression compared to saline/saline group in the hypothalamus, testis and liver. Injections of kisspeptin/morphine did not significantly decrease mean relative 5α-reductase or aromatase genes expression compared to morphine/saline group. Up-regulation of hypothalamic 5α-reductase or aromatase mRNA levels may partly induce the inhibitory effects of morphine on GnRH/LH release. Different effects of morphine on aromatase or 5α- reductase genes expression levels in the liver and testis compared to brain may be partly due to different sensitivity or functions of them to morphine used dose.

This research is to study the influences of different concentrations of simvastatin on the biological activities of nucleus pulposus-derived mesenchymal stem cells (NPMSC). NPMSC were cultured with different concentrations of simvastatin (0, 0.01, 0.1, and 1 μM) and assessed to determine the possible effects of simvastatin. The cell proliferation was assessed with CCK-8 assay. The flowcytometry and multilineage differentiation were also performed to identify the stem characterization of the cells. The mRNA expressions of aggrecan, collagen type II, glucose transporter 1 (GLUT-1), vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) were determined by qRT-PCR. The results demonstrated that the cells isolated from nucleus pulposus of healthy Sprague-Dawley (SD) rat met the criteria of MSC. NPMSC could form sunflower-like colonies and strongly expressed stem cell-related genes. In addition, NPMSC showed strong ability of chondrogenic, adipogenic and osteogenic differentiation. Simvastatin at certain range concentrations (0.01 μM-0.1 μM)) significantly promoted colony-forming rate and cell proliferation, and inhibited cell apoptosis. Simvastatin could promote expressions of aggrecan, collagen type II, HIF-1α, VEGF and GLUT-1, while 0.1 μmol/l concentration reached the maximum effect. Our study further demonstrated that HIF-1α-intermediated signaling pathway might participate in regulating the biological activities of NPMSC. Proper concentration of simvastatin can promote the biological behavior of NPMSC, and HIF-1α-intermediated signaling pathway might participate in the mechanism.

Olanzapine, an atypical antipsychotic, causes weight gain and metabolic disorders in humans. Safranal, one of the active components of Crocus sativus (saffron), has been shown to have anti-obesity, lipid and blood pressure lowering and anti-diabetes effects. In this investigation, the effect of safranal on metabolic disorders induced by olanzapine was studied. Fourty-two female Wistar rats were divided into 7 groups of 6 animals. The two groups were selected as controls, which received olanzapine and safranal solvents, respectively. The third group treated by olanzapine 5 mg/kg. Groups 4, 5 and 6 treated by olanzapine 5 mg/kg plus safranal (2.5, 5 and 10 mg/kg) and the last group received safranal 10 mg/kg. The injections were performed intraperitoneally for 14 days and on the 15th day the rats were killed and their serum were collected to measure metabolic factors including glucose, insulin, triglyceride, total cholesterol and HDL cholesterol. Leptin level in plasma was also measured. Mean systolic blood pressure was measured using tail cuff method at the end of study. The rats were weighed every other day and amount of food consumed was measured daily. Olanzapine significantly elevated body weight, food intake, fasting blood glucose, TG, leptin, and mean systolic blood pressure (MSBP). It also significantly decreased HDL cholesterol blood level. Safranal significantly improved all these complications at three doses. Based on the results of this study, safranal is thought to be used as an effective combination in controlling metabolic complications caused by olanzapine.

Aspiration is a common cause of acute lung injury (ALI), which lacks an effective treatment. Inflammation and oxidative stress play key roles in ALI development. Silymarin is an active extract of Silybum marianum plant seeds (milk thistle). Silymarin has potent anti-inflammatory and antioxidant effects; however its role in aspiration induced ALI has not been investigated. The aim of this study is to investigate the role of silymarin in the treatment of hydrochloric acid (HCl) aspiration induced ALI and explores its mechanisms of action.

The study included three groups of rats: Control non-treated group, ALI group (intra-tracheal HCl injected), and silymarin treated ALI group. White blood cells (WBCs) with differential count, oxidative stress parameters, B-cell lymphoma 2 (Bcl-2), transforming growth factor-beta (TGF-β), cyclooxygenase 2 (COX-2), nuclear factor erythroid 2-related factor-2 (Nrf-2), and heme oxygenase-1 (HO-1) were investigated. Lung tissue histopathology and immunohistochemical expression of survivin and proliferating cell nuclear antigen (PCNA) were also examined.

The results of the study showed that HCL caused histopathological changes in ALI with leukocytopenia and increased oxidative stress biomarkers. It increased TGF-β, up-regulated mRNA expression of COX-2, Nrf-2, and HO-1 and increased survivin and PCNA but decreased Bcl-2. Silymarin ameliorated the histopathological lung injury with further up-regulation of Nrf-2 and HO-1 mRNA and decreased the inflammatory and fibrotic parameters together with up-regulation of the anti-apoptotic and the proliferation parameters.

The protective effect of silymarin against ALI is mediated by Nrf-2/HO-1 pathway with subsequent antioxidant, anti-inflammatory, antiapoptotic, and proliferating activities.

To design a multivalent DNA vaccine encoding the most immunogenic regions of the Leishmania major antigens including TSA (Thiol-specific antioxidant protein), LmSTI1 (Leishmania major stress-inducible protein1), LACK (Leishmania homologue of receptors for activated C Kinase), and KMP11 (kinetoplastid membrane protein-11) on BALB/c mice.

The chimeric construct was generated including the most immunogenic epitopes containing a combination of domains and oligopeptides of the aforementioned genes. The construct was cloned into pcDNA 3.1 plasmid and named “pleish-dom.” Following intramuscular injection of mice, the capability of the vector pleish-dom alone and with pIL-12 (expressing murine IL-12) to raise protective cytokines and parasite burden was evaluated in the BALB/c mice as a susceptible animal model against L. major.

The immunized mice with pleish-dom/pIL-12 showed the highest and the lowest levels of interferon-gamma (IFN-γ) and interleukin-10 (IL-10), as well as the lowest leishmanin skin test (LST) reactions, were found through 8 weeks post-infection.

Although the obtained DNA vaccine from the immunogenic chimeric protein of L. major antigens was able to induce a high level of IFN-γ, it partially protected mice against L. major. However co-administration with pIL-12 led to shift immune response to Th1 phenotype, granuloma formation, and lowered parasite burden, and consequently distinct protection was found.