Differences in AMPA and kainate receptor interactomes facilitate identification of AMPA receptor auxiliary subunit GSG1L

1. Download : Download full-size image

Highlights? Mass spectrometry identified proteins copurifying with AMPA and kainate receptors ? GSG1L is an AMPA-receptor-binding transmembrane protein ? GSG1L uniquely modulates AMPA receptor trafficking and channel gating ? GSG1L colocalizes with AMPA receptors at synapses     

Association of Pb,Cd, and Se Concentrations and Oxidative Damage-Related Markers in Different Grades of Prostate Carcinoma

Prostate cancer is known to be affected by the heavy metal levels and oxidative damage of the body, yet there are very few studies which look into the way it occurs. The aim of this study was to determine whether blood and tissue lead (Pb), cadmium (Cd), and selenium (Se) levels are associated with oxidative damage in the context of prostate cancer progression and development. Seventy-nine patients comprising 25 patients with benign prostatic hypertrophy (BPH), 23 patients with malignant prostatic carcinoma (malign Ca), 16 patients with low-grade prostatic intraepithelial neoplasia (LGPIN), and 15 patients with high-grade prostatic intraepithelial neoplasia (HGPIN) diagnosed on the basis of their clinical profile, transrectal ultrasonography, and histopathology were included in this study. Cd and Pb levels in whole blood were found to be increased in patients with HGPIN compared with the BPH group; also, the levels of Cd in whole blood and tissue were found to be increasing in patients with malign Ca, unlike BPH patients. Moreover, the levels of malondialdehyde (MDA) in plasma and tissue were significantly increased in malign Ca, LGPIN, and HGPIN than those in BPH. However, the levels of tissue Pb were found to be decreasing in BPH, unlike the malign Ca and HGPIN patients, and the levels of tissue protein carbonyls in malign Ca were significantly lower than those in HGPIN. The levels of tissue reduced glutathione (GSH) in malign Ca were significantly lower than those in BPH. Additionally, the levels of Se in serum and tissue in LGPIN were significantly lower than those in BPH. The serum Se levels in HGPIN were also significantly lower than those in BPH and malign Ca groups. Furthermore, the concentrations of serum Se in LGPIN were significantly lower than those in malign Ca. From the Pearson correlation analysis, there were significant positive correlations between tissue Cd and MDA levels in malign Ca, LGPIN, and HGPIN and between the tissue Pb and tissue MDA and protein carbonyl levels in malign Ca. Blood Pb and tissue Pb were also significantly positively correlated with plasma MDA and protein carbonyl levels in malign Ca. In addition, blood Pb was significantly positively correlated with tissue MDA and protein carbonyl levels in malign Ca, and a significant positive correlation was also found between blood Cd and plasma protein carbonyls and tissue MDA in LGPIN. We observed that altered prooxidant–antioxidant balance and heavy metal levels may lead to an increase in oxidative damage and may consequently play an important role in prostate carcinogenesis. These findings indicate that changes in the levels of Pb, Cd, Se, MDA, protein carbonyls, and GSH in the blood and/or tissue are related to the prostatic carcinoma development and progression, although triggering one of the mentioned changes is unknown; therefore, further study is required to determine the exact steps of the process and clarify the roles of different substances in order to obtain a more detailed explanation of the phenomenon.     

Is subclinical hypothyroidism contributing dyslipidemia and insulin resistance in women with polycystic ovary syndrome?

We aimed to analyze lipid parameters and determine the need for a 2-hour oral glucose tolerance test (OGTT) for the identification of IR and impaired glucose tolerance test (IGT) in subclinical hypothyroidism (SCH) women with and without polycystic ovary syndrome (PCOS). 20 patients with PCOS and SCH consisted of Group I and 39 patients with PCOS and normal thyroid function consisted of Group II and 53 healthy women with normal thyroid function consisted of Group III. Triglyceride levels were 143.26?±?99.86?mg/dL in group 1 and 88.56?±?37.56?mg/dL in group 2 and 83.71?±?31.94?mg/dL in group 3 which were statistically significant. Total cholesterol, HDL- cholesterol, LDL-cholesterol were found similar between the groups. Fasting insulin levels were 12.45?±?8.62 μU/mL in group 1 and 8.60?±?5.35 μU/mL in group 2 and 7.04?±?3.55 μU/mL in group 3 which were statistically significant (P?=?0.027). HOMA-IR were 2.92?±?2.34 in group 1 and 1.95?±?1.52 in group 2 and 1.60?±?0.86 in group 3 which were statistically significant (P?=?0.046). This study showed that women with PCOS and subclinical hypothyroidism should be evaluated for dyslipidemia and Insulin resistance.     

Chemical characterization and evaluation of the neuroprotective potential of Indigofera sessiliflora through in-silico studies and behavioral tests in scopolamine-induced memory compromised rats

In the current study, we investigated the phytochemical and neuropharmacological potential of Indigofera sessiliflora, an indigenous least characterized plant widely distributed in deserted areas of Pakistan. The crude extract of the whole plant Indigofera sessiliflora (IS.CR) was preliminary tested in-vitro for the existence of polyphenol content, antioxidant and anticholinesterase potential followed by detailed chemical characterization through UHPLC-MS. Rats administered with different doses of IS.CR (100–300 mg/kg) for the duration of 4-weeks were behaviorally tested for anxiety and cognition followed by biochemical evaluation of dissected brain. The in-silico studies were employed to predict the blood–brain barrier crossing tendencies of secondary metabolites with the elucidation of the target binding site. The in-vitro assays revealed ample phenols and flavonoids content in IS.CR with adequate anti-oxidant and anticholinesterase potential. The dose-dependent anxiolytic potential of IS.CR was demonstrated in open field (OFT), light/dark (L/D) and elevated plus maze (EPM) tests as animals spent more time in open, illuminated and elevated zones (P < 0.05). In the behavioral tests for learning/memory, the IS.CR reversed the scopolamine-induced cognitive deficits, as animals showed better (P < 0.05) spontaneous alternation and discrimination index in y-maze and novel object recognition (NOR) tests. Similarly, as compared to amnesic rats, the step-through latencies were increased (P < 0.05) and escape latencies were decreased (P < 0.05) in passive avoidance (PAT) and Morris water maze (MWM) tests, respectively. Biochemical analysis of rat brains showed significant reduction in malondialdehyde and acetylcholinesterase levels, alongwith preservation of glutathione peroxidase and superoxide dismutase activity. The docking studies further portrayed a possible interaction of detected phytoconstituents with acetylcholinesterase target. The results of the study show valuable therapeutic potential of phytoconstituents present in IS.CR to correct the neurological disarrays which might be through antioxidant activity or via modulation of GABAergic and cholinergic systems by artocommunol, 1,9-dideoxyforskolin and 6E,9E-octadecadienoic acid.     

Evaluation of the Rho A/Rho-kinase pathway in the uterus of the rat model of polycystic ovary syndrome

The aim of this study was to investigate the expression of RhoA/Rho-kinase in the uterus and the effect of Rho-kinase inhibitors on uterine contractions of dehydroepiandrosterone (DHEA) induced polycystic ovary syndrome (PCOS) rats. Forty-four female Sprague-Dawley (21 days old) rats divided into three groups: The control group (n?=?14, any procedure was not performed), vehicle group (n?=?14, 0.2?ml of sesame oil, subcutaneous injection, 20 days) and PCOS group (n?=?16, DHEA 6?mg/100?g in 0.2?ml of sesame oil, subcutaneous injection, 20 days). The myometrium thickness and uterine wet weight were assessed. The mRNA and protein expressions of Rho A, the effect of Rho-kinase inhibitors (fasudil and Y-27632) on KCl, carbachol, and PGF2α induced contractions were evaluated in the uterus. In the PCOS group, the myometrium thickness and uterine wet weight significantly increased compared to the control group and vehicle group. The mRNA expression level and the immunoreactive score of Rho A, ROCK 1, ROCK 2 were similar in all groups. In the PCOS group, KCl, carbachol, and PGF2α induced uterine contractions significantly increased compared to the control group and vehicle group. Fasudil and Y-27632 significantly inhibited KCl, carbachol, and PGF2α induced uterine contractions in all groups. In conclusion, the expression of Rho A, ROCK 1, ROCK 2 not changed although myometrium thickness, uterine wet weight and the contractile responses of uterus increased in the PCOS group. The results suggest that the Rho-kinase inhibitors effectively suppressed increased contractions in the PCOS group they might be potential therapeutic agents.     

Larval-rearing and growout of the red porgy (Pagrus pagrus) in the Riopesca hatchery (Greece)

Juveniles of red porgy (Pagrus pagrus 1758 L.) were experimentallyproduced in RIOPESCA hatchery during Spring 1992–95. Wild broodstock,weighing from 500 to 1000 g, was caught and brought to the hatchery insummer 1991. They were placed in a 30 m³ rectangular outdoorbroodstock tank with a sea-water flow of 5 m³ per hour.Salinity ranged from 3.9 to 4.1%, temperature from 13 to25°C , the stocking density was 4 kg m^–3,and the sex ratio was 1:1. The females spawned spontaneously in captivity producing approximately 200 000 eggs per kg of body weight. The percent offertilization was between 85–95%. Hatching was completed 85 hours later at 18 °C with a hatching percent of80–90%. The larvae were introduced into a 15 m³tank using green water (Nannochloropsis gaditana & Isochrysis galbana)and fed rotifers (Brachionus rotundiformis), Artemia salina nauplii andmetanauplii, and artificial food. After the end of the weaning period (day80 posthatch) the juveniles reached a weight of 1.4 g with a mean percentof survival of 10%. The fry were transferred to a cage site in which the growout proceeded without particular difficulties. The onlyproblem during growout was the skin coloration, that was darker than thatof wild porgies. Red porgies growth in our installations is satisfactory,with fry reaching 360 ± 12 g within 19 months, with a foodconversion rate of 1.8:1 , and a 6% mortality.     

Continuous gluconic acid production by the yeast-like Aureobasidium pullulans in a cascading operation of two bioreactors

The application of a new developed process for the continuous production of gluconic acid using a cascade of two bioreactors in a continuous process is shown reaching the highest concentration of gluconic acid described in the literature for continuous culture fermentation. Very high gluconic acid concentrations of 272-308 g/l have been achieved under continuous cultivation of free-growing cells of Aureobasidium pullulans in the first bioreactor at residence times (RT) between 19.5 and 24 h with formation rates for the generic product between 12.7 and 13.9 g/(l h). Gluconic acid, 350-370 g/l, was continuously reached in the second bioreactor at a total RT of 30.8-37 h with R (j) of 9.2-12 g/(l h). The highest specific gluconic acid production (m (p)) of 3.6 g/(g h) was found in the first bioreactor at the lowest RT of 19.5 h. The highest selectivity of 93.6% was determined in the first bioreactor as well. Complete glucose consumption was obtained at 37 h total residence time in the second bioreactor. Gluconic acid, 433 g/l, was continuously produced in the second bioreactor at a total RT of 37 h.     

Kinetics of reversible N-ethylmaleimide alkylation of metallothionein and the subsequent metal release

 The model alkylating agent N-ethylmaleimide (NEM) reacts reversibly at the metal-bound thiolates of Zn₇MT and Cd₇MT. An unprecedented feature of this reaction is that it approaches equilibrium and requires a large excess of NEM (>1 mM for 3 μM protein) to drive it to completion. The complex kinetics of the reaction can be followed by monitoring the release of bound metal ions using the metallochromic dyes Zincon (ZI) for Zn₇MT and pyridylazoresorcinol for Cd₇MT. An initial lag phase is followed by more rapid release of zinc ions. The observed pseudo-first-order rate constants for the two phases are independent of the ZI and Zn₇MT concentrations. The complex NEM concentration dependence of each phase, k _f, obs=k ^f ₁+k ^f ₂ [NEM] and k _s, obs=k ^s ₁+k ^s ₂ [NEM], demonstrates that the forward reactions are second order and the reverse reactions are first order. The alkylation can be reversed using 2-mercaptoethanol to compete for the protein-bound NEM and regenerate the Zn-binding capability of alkylated MT. An explanation of these observations, based on the reversibility of cysteine alkylation by NEM, was developed and tested. The reactions of Cd₇MT are less complete than those of Zn₇MT and occur more slowly. ¹¹¹Cd-NMR studies of the partially alkylated ¹¹¹Cd₇MT reveal that reaction with only four equivalents of NEM completely alters the cluster structure and eliminates the spectral signatures of the α and β clusters, although very little cadmium has been removed from the protein. This finding substantiates the proposed kinetic intermediate, a partially alkylated MT with complete or nearly complete retention of the metal ions, and rules out the possibility of cooperative reactions at either cluster. Received: 5 August 1996 / Accepted: 24 October 1996