Sex-Dependent Changes in Striatal Dopamine Transport in Preadolescent Rats Exposed Prenatally and/or Postnatally to Methamphetamine

Methamphetamine (MA) is the most commonly used psychostimulant drug, the chronic abuse of which leads to neurodegenerative changes in the brain. The global use of MA is increasing, including in pregnant women. Since MA can cross both placental and haematoencephalic barriers and is also present in maternal milk, children of chronically abused mothers are exposed prenatally as well as postnatally. Women seem to be more vulnerable to some aspects of MA abuse than men. MA is thought to exert its effects among others via direct interactions with dopamine transporters (DATs) in the brain tissue. Sexual dimorphism of the DAT system could be a base of sex-dependent actions of MA observed in behavioural and neurochemical studies. Possible sex differences in the DATs of preadolescent offspring exposed to MA prenatally and/or postnatally have not yet been evaluated. We examined the striatal synaptosomal DATs (the activity and density of surface expressed DATs and total DAT expression) in preadolescent male and female Wistar rats (31–35-day old animals) exposed prenatally and/or postnatally to MA (daily 5 mg/kg, s.c. to mothers during pregnancy and lactation). To distinguish between specific and nonspecific effects of MA on DATs, we also evaluated the in vitro effects of lipophilic MA on the fluidity of striatal membranes isolated from preadolescent and young adult rats of both sexes. We observed similar changes in the DATs of preadolescent rats exposed prenatally or postnatally (MA-mediated drop in the reserve pool but no alterations in surface-expressed DATs). However, prenatal exposure evoked significant changes in males and postnatal exposure in females. A significant decrease in the activity of surface-expressed DATs was found only in postnatally exposed females sensitized to MA via prenatal exposure. MA applied in vitro increased the fluidity of striatal membranes of preadolescent female but not male rats. In summary, DATs of preadolescent males are more sensitive to prenatal MA exposure via changes in the reserve pool and those of preadolescent females to postnatal MA exposure via the same mechanism. The combination of prenatal and postnatal MA exposure increases the risk of dopaminergic deficits via alterations in the activity of surface-expressed DATs especially in preadolescent females. MA-mediated changes in DATs of preadolescent females could be still enhanced via nonspecific disordering actions of MA on striatal membranes.     

Mitochondrial dysfunction in fibroblasts of Multiple System Atrophy

Multiple System Atrophy is a severe neurodegenerative disorder which is characterized by a variable clinical presentation and a broad neuropathological spectrum. The pathogenic mechanisms are almost completely unknown. In the present study, we established a cellular model of MSA by using fibroblasts' primary cultures and performed several experiments to investigate the causative mechanisms of the disease, with a particular focus on mitochondrial functioning.Fibroblasts' analyses (7 MSA-P, 7 MSA-C and 6 healthy controls) displayed several anomalies in patients: an impairment of respiratory chain activity, in particular for succinate Coenzyme Q reductase (p?<?0.05), and a reduction of complex II steady-state level (p?<?0.01); a reduction of Coenzyme Q10 level (p?<?0.001) and an up-regulation of some CoQ10 biosynthesis enzymes, namely COQ5 and COQ7; an impairment of mitophagy, demonstrated by a decreased reduction of mitochondrial markers after mitochondrial inner membrane depolarization (p?<?0.05); a reduced basal autophagic activity, shown by a decreased level of LC3 II (p?<?0.05); an increased mitochondrial mass in MSA-C, demonstrated by higher TOMM20 levels (p?<?0.05) and suggested by a wide analysis of mitochondrial DNA content in blood of large cohorts of patients.The present study contributes to understand the causative mechanisms of Multiple System Atrophy. In particular, the observed impairment of respiratory chain activity, mitophagy and Coenzyme Q10 biosynthesis suggests that mitochondrial dysfunction plays a crucial role in the pathogenesis of the disease. Furthermore, these findings will hopefully contribute to identify novel therapeutic targets for this still incurable disorder.     

Metabolic Induction of Trained Immunity through the Mevalonate Pathway

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Cloning,Characterization, and Expression Levels of the <Emphasis Type="Italic">Nectin</Emphasis> Gene from the Tube Feet of the Sea Urchin <Emphasis Type="Italic">Paracentrotus Lividus</Emphasis>

Marine bioadhesives perform in ways that manmade products simply cannot match, especially in wet environments. Despite their technological potential, bioadhesive molecular mechanisms are still largely understudied, and sea urchin adhesion is no exception. These animals inhabit wave-swept shores, relying on specialized adhesive organs, tube feet, composed by an adhesive disc and a motile stem. The disc encloses a duo-gland adhesive system, producing adhesive and deadhesive secretions for strong reversible substratum attachment. The disclosure of sea urchin Paracentrotus lividus tube foot disc proteome led to the identification of a secreted adhesion protein, Nectin, never before reported in adult adhesive organs but, that given its adhesive function in eggs/embryos, was pointed out as a putative substratum adhesive protein in adults. To further understand Nectin involvement in sea urchin adhesion, Nectin cDNA was amplified for the first time from P. lividus adhesive organs, showing that not only the known Nectin mRNA, called Nectin-1 (GenBank AJ578435), is expressed in the adults tube feet but also a new mRNA sequence, called Nectin-2 (GenBank KT351732), differing in 15 missense nucleotide substitutions. Nectin genomic DNA was also obtained for the first time, indicating that both Nectin-1 and Nectin-2 derive from a single gene. In addition, expression analysis showed that both Nectins are overexpressed in tube feet discs, its expression being significantly higher in tube feet discs from sea urchins just after collection from the field relative to sea urchin from aquarium. These data further advocate for Nectin involvement in sea urchin reversible adhesion, suggesting that its expression might be regulated according to the hydrodynamic conditions.     

Prevalence of adult ADHD in an all-female prison unit

There is increasing evidence suggesting a link between ADHD and criminality, including a strong association between ADHD symptoms and the likelihood of being on probation or in prison. Most studies investigating the prevalence of ADHD in prison populations have focused on adult male offenders. In the current study, 69 female prisoners were screened for both childhood and adult ADHD symptoms using the Barkley Adult ADHD Rating Scale-IV. The results indicate that 41 % of the prisoners met the diagnostic criteria for ADHD in childhood and continued to meet criteria for ADHD as adults. More importantly, young female prisoners (aged 18–25) were significantly more likely to report symptoms of ADHD than older prisoners. Prisoners who reported symptoms of ADHD also reported high levels of impairment associated with these symptoms. A better understanding of the prevalence of ADHD in female prison units can highlight specific areas for intervention during rehabilitation, as well as the management of serious incidents within prison.     

Influence of ACE I/D Polymorphism on Circulating Levels of Plasminogen Activator Inhibitor 1, D-Dimer,Ultrasensitive C-Reactive Protein and Transforming Growth Factor β1 in Patients Undergoing Hemodialysis

Background

There is substantial evidence that chronic renal and cardiovascular diseases are associated with coagulation disorders, endothelial dysfunction, inflammation and fibrosis. Angiotensin-Converting Enzyme Insertion/Deletion polymorphism (ACE I/D polymorphism) has also be linked to cardiovascular diseases. Therefore, this study aimed to compare plasma levels of ultrassensible C-reactive protein (usCRP), PAI-1, D-dimer and TGF-β1 in patients undergoing HD with different ACE I/D polymorphisms.

Methods

The study was performed in 138 patients at ESRD under hemodialysis therapy for more than six months. The patients were divided into three groups according to the genotype. Genomic DNA was extracted from blood cells (leukocytes). ACE I/D polymorphism was investigated by single polymerase chain reaction (PCR). Plasma levels of D-dimer, PAI-1 and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA), and the determination of plasma levels of usCRP was performed by immunonephelometry. Data were analyzed by the software SigmaStat 2.03.

Results

Clinical characteristics were similar in patients with these three ACE I/D polymorphisms, except for interdialytic weight gain. I allele could be associated with higher interdialytic weight gain (P = 0.017). Patients genotyped as DD and as ID had significantly higher levels of PAI-1 than those with II genotype. Other laboratory parameters did not significantly differ among the three subgroups (P = 0.033). Despite not reaching statistical significance, plasma levels of usCRP were higher in patients carrying the D allele.

Conclusion

ACE I/D polymorphisms could be associated with changes in the regulation of sodium, fibrinolytic system, and possibly, inflammation. Our data showed that high levels of PAI-1 are detected when D allele is present, whereas greater interdialytic gain is associated with the presence of I allele. However, further studies with different experimental designs are necessary to elucidate the mechanisms involved in these associations.     

Blood Thixotropy in Patients with Sickle Cell Anaemia: Role of Haematocrit and Red Blood Cell Rheological Properties

We compared the blood thixotropic/shear-thinning properties and the red blood cells’ (RBC) rheological properties between a group of patients with sickle cell anaemia (SS) and healthy individuals (AA). Blood thixotropy was determined by measuring blood viscosity with a capillary viscometer using a “loop” protocol: the shear rate started at 1 s⁻¹ and increased progressively to 922 s⁻¹ and then re-decreased to the initial shear rate. Measurements were performed at native haematocrit for the two groups and at 25% and 40% haematocrit for the AA and SS individuals, respectively. RBC deformability was determined by ektacytometry and RBC aggregation properties by laser backscatter versus time. AA at native haematocrit had higher blood thixotropic index than SS at native haematocrit and AA at 25% haematocrit. At 40% haematocrit, SS had higher blood thixotropic index than AA. While RBC deformability and aggregation were lower in SS than in AA, the strength of RBC aggregates was higher in the former population. Our results showed that 1) anaemia is the main modulator of blood thixtropy and 2) the low RBC deformability and high RBC aggregates strength cause higher blood thixotropy in SS patients than in AA individuals at 40% haematocrit, which could impact blood flow in certain vascular compartments.     

The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6 +/- mouse model of epithelial wound-healing delay

Background  

Congenital aniridia caused by heterozygousity at the PAX6 locus is associated with ocular surface disease including keratopathy. It is not clear whether the keratopathy is a direct result of reduced PAX6 gene dosage in the cornea itself, or due to recurrent corneal trauma secondary to defects such as dry eye caused by loss of PAX6 in other tissues. We investigated the hypothesis that reducing Pax6 gene dosage leads to corneal wound-healing defects. and assayed the immediate molecular responses to wounding in wild-type and mutant corneal epithelial cells.     

Oxidative stress activates AMPK in cultured cells primarily by increasing cellular AMP and/or ADP

AMPK is known to be activated by oxidative stress. Addition of glucose oxidase to cells generates H₂O₂ at a constant rate that is opposed by enzymic degradation, providing a good model for physiological oxidative stress. AMPK activation by glucose oxidase correlated with increases in cellular AMP:ATP and was greatly reduced in cells expressing an AMP-insensitive AMPK mutant, although a small degree of activation remained. The effects of increased AMP were partly due to inhibition of Thr172 dephosphorylation. These results suggest that changes in adenine nucleotides, rather than direct oxidative modification, are the major drivers of AMPK activation during oxidative stress.