Exogenously administered and endogenously produced melatonin reduce hyperbaric oxygen-induced oxidative stress in rat lung

Hyperbaric oxygen (HBO) is a widely used treatment modality in many diseases. A known side effect of HBO is the production of reactive oxygen species. Many antioxidants such as vitamins C and E, riboflavin and selenium have been used successfully to scavenge the reactive oxygen species caused by HBO administration. In this study, we aimed to see if melatonin, a newly discovered antioxidant, has a protective effect against the overproduction of reactive oxygen species produced by HBO in rat lung tissue. Sixty male Sprague-Dawley rats were divided into 5 groups as follows: control, daytime HBO (3 ATA, 120 min), daytime HBO plus melatonin (10 mg/kg), nighttime HBO and nighttime HBO (under light exposure). The MDA, SOD and CAT levels of daytime and nighttime HBO (under light exposure) increased significantly. This significance was not found in the daytime HBO plus melatonin and nighttime HBO groups when compared with the control. In this study, HBO caused oxidant stress, and melatonin decreased the levels of MDA, SOD and CAT. Moreover, endogenous melatonin was found to be a more effective antioxidant than exogenous 10 mg/kg melatonin.     

Cortisol and hypothalamic-pituitary-gonadal axis hormones in follicular-phase women with fibromyalgia and chronic fatigue syndrome and effect of depressive symptoms on these hormones

We investigated abnormalities of the hypothalamic-pituitary-gonadal axis and cortisol concentrations in women with fibromyalgia and chronic fatigue syndrome (CFS) who were in the follicular phase of their menstrual cycle, and whether their scores for depressive symptoms were related to levels of these hormones. A total of 176 subjects participated - 46 healthy volunteers, 68 patients with fibromyalgia, and 62 patients with CFS. We examined concentrations of follicle-stimulating hormone, luteinizing hormone (LH), estradiol, progesterone, prolactin, and cortisol. Depressive symptoms were assessed using the Beck Depression Inventory (BDI). Cortisol levels were significantly lower in patients with fibromyalgia or CFS than in healthy controls (P < 0.05); there were no significant differences in other hormone levels between the three groups. Fibromyalgia patients with high BDI scores had significantly lower cortisol levels than controls (P < 0.05), and so did CFS patients, regardless of their BDI scores (P < 0.05). Among patients without depressive symptoms, cortisol levels were lower in CFS than in fibromyalgia (P < 0.05). Our study suggests that in spite of low morning cortisol concentrations, the only abnormalities in hypothalamic-pituitary-gonadal axis hormones among follicular-phase women with fibromyalgia or CFS are those of LH levels in fibromyalgia patients with a low BDI score. Depression may lower cortisol and LH levels, or, alternatively, low morning cortisol may be a biological factor that contributes to depressive symptoms in fibromyalgia. These parameters therefore must be taken into account in future investigations.     

A novel and one-pot synthesis of new 1-tosyl pyrrol-2-one derivatives and analysis of carbonic anhydrase inhibitory potencies

Here we propose a novel one-pot synthesis of new tosyl-pyrrole derivatives. By means of the new developed method, pyrrole derivatives were synthesized at room temperature in a single step, and a useful method is proposed for the synthesis of similar compounds. Moreover, inhibitions of two human cytosolic carbonic anhydrase (hCA, EC 4.2.1.1) isozymes I and II by 1-tosyl-pyrrole and 1-tosyl-pyrrol-2-on derivatives were investigated. 1-Tosyl-pyrrole, 1-tosyl-1H-pyrrol-2(5H)-one, 5-hydroxy-1-tosyl-1H-pyrrol-2(5H)-one and 5-oxo-1-tosyl-2,5-dihydro-1H-pyrrol-2-yl acetate showed inhibitory action with K_i values in the range of 14.6–42.4 μM for hCA I and 0.53–37.5 μM for hCA II, respectively. All pyrrole derivatives were competitive inhibitors with 4-nitrophenylacetate as substrate. Some new synthesized pyrrole derivatives showed very effective hCA II inhibitory effects, in the same range as the clinically used sulfonamide acetazolamide, and might be used as leads for generating enzyme inhibitors targeting other CA isoforms.     

Conducting-state properties of the KcsA potassium channel from molecular and Brownian dynamics simulations.

The mechanisms underlying transport of ions across the potassium channel are examined using electrostatic calculations and three-dimensional Brownian dynamics simulations. We first build open-state configurations of the channel with molecular dynamics simulations, by pulling the transmembrane helices outward until the channel attains the desired interior radius. To gain insights into ion permeation, we construct potential energy profiles experienced by an ion traversing the channel in the presence of other resident ions. These profiles reveal that in the absence of an applied field the channel accommodates three potassium ions in a stable equilibrium, two in the selectivity filter and one in the central cavity. In the presence of a driving potential, this three-ion state becomes unstable, and ion permeation across the channel is observed. These qualitative explanations are confirmed by the results of three-dimensional Brownian dynamics simulations. We find that the channel conducts when the ionizable residues near the extracellular entrance are fully charged and those near the intracellular side are partially charged. The conductance increases steeply as the radius of the intracellular mouth of the channel is increased from 2 A to 5 A. Our simulation results reproduce several experimental observations, including the current-voltage curves, conductance-concentration relationships, and outward rectification of currents.     

Syntheses and evaluation of multicaulin and miltirone-like compounds as antituberculosis agents

Four multicaulin and miltirone-like phenanthrene derivatives were synthesised and evaluated as antituberculosis agents. The crucial step of the synthesis was Pschorr coupling of 4-(3-isopropyl-4-methoxyphenyl)-2-(2-aminophenyl)ethane (13) to give 2-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9) and 4-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9a). Compound 9 was converted to multicaulin and miltirone-like phenanthrene derivatives by further reactions. The best antituberculosis activity was exhibited by 2-isopropylphenanthrene-3-ol (11).     

Population genetic structure and phylogeography of the oak gall wasp Andricus chodjaii (Hymenoptera: Cynipidae) in Turkey as inferred from mitochondrial and nuclear DNA sequences

Sequence data of mitochondrial cytochrome b gene and nuclear ITS2 region were used to assess genetic diversity, intraspecific phylogeography and population genetic structure of the oak gall wasp Andricus chodjaii from Turkey. We examined 293 individuals from 21 localities which generated 57 cyt b haplotypes and 8 ITS2 alleles. The average genetic diversity was 0.575 for cyt b and 0.202 ITS2, and the average nucleotide diversity 0.015 for cyt b gene and 0.001 for the ITS2 region. Phylogenetic analyses of cyt b haplotypes produced mostly similar topologies with geographically significant groupings. The ITS2 data provided less resolution without robust and apparent geographic structure. Population demographic analysis indicated that some eastern populations expanded, however, some others underwent either expansion or decline resulting in genetically structured populations. Molecular clock applied to the mtDNA data indicated that ingroup haplotypes diversified from the outgroup haplotypes around Early Pliocene. Further diversification events throughout Pleistocene resulted in major clade formations. It appears that geographic formations and glacial and interglacial cycles of Pleistocene were crucial for shaping the phylogeographic structure of A. chodjaii in Turkey.     

The effect of a natural molecule in ovary ischemia reperfusion damage: does lycopene protect ovary?

Ovarian ischemia is a gynecological emergency case that occurs as a result of ovarian torsion. Oxidative stress plays a central role in the development of ischemia/reperfusion (IR) injuries. Lycopene (LYC) is a lipophilic, natural carotenoid well known for its antioxidant properties. This study provides information on the potential applications of lycopene. The Wistar Albino rats were distributed into six groups: Sham group (only a laparotomy was performed), Control group [laparotomy and intraperitoneal dissolvent (olive oil)], IR group, IR+olive oil group, IR+LYC 2.5 mg/kg/dose, intraperitoneal group, IR+LYC 5 mg/kg/dose intraperitoneal group. Evaluated in terms of histopathological changes, tissue malondialdehyde levels (MDA), ovarian expressions of phosphorylated nuclear factor-kappa B (p-NF-κB) and the TUNEL method was utilized to show apoptosis of ovarian tissue. There was a significant decrease in MDA, p-NF-κB values and the proportion of apoptotic cells assessed by TUNEL compared to the group that did not receive intraperitoneal LYC in rat injury with IR damage (P<0.05). In histopathological damage scoring, it was observed that the cell damage was significantly reduced in LYC-administered groups. LYC showed significant ameliorative effects on ovary injury caused by IR through acting as an antioxidant, antiinflammatory, and antiapoptotic agent.     

Comparison of oxidative stress and antioxidant capacity before and after running exercises in both sexes

Background: It has been difficult to determine, from the published literature, whether men or women have higher levels of exercise-induced oxidative stress.Objective: The aim of this study was to compare variations between the sexes in lipid hydroperoxide (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and lactate dehydrogenase (LDH) after 3 different running exercises performed at the same speed.Methods: Eligible participants were healthy university students of both sexes. The participants performed running exercise tests at distances of 800, 1500, and 3000 m at a speed of 10 km/h. Blood samples were taken from the participants just before and immediately after the running activities to determine LPO, SOD, CAT, GR, and LDH, and these measures were compared both before and after exercise and between the sexes.Results: A total of 17 young and healthy, but not physically trained, students (n = 8 men; mean age, 22.00 years; n = 9 women; mean age, 21.78 years) participated in this study. Height, weight, and maximum oxygen consumption values were significantly higher in men than in women (P = 0.01). Significant gender effects were found in LPO levels at 3000 m (F = 5.51; P = 0.03) and in SOD activity at 800 m (F = 7.92; P = 0.01) and 3000 m (F = 6.05; P = 0.03). CAT activity also differed between the sexes at 800 m (F = 15.67; P = 0.01) and 1500 m (F = 6.55; P = 0.02). However, no significant gender-time interaction effect was observed for any measurement at the 800-, 1500-, and 3000-m distances.Conclusions: Changes in LPO, SOD, and CAT activities at different running distances were not different between men and women over time because of a nonsignificant gender-time interaction. With regard to changes in oxidative stress, men and women had similar responses to exercise at the same absolute workload, despite significant differences in physical characteristics.