Identification of Bilateral Changes in TID1 Expression in the 6-OHDA Rat Model of Parkinson's Disease

Parkinson's disease (PD) is a common neurodegenerative disease characterized by the loss of dopaminergic neurons in the substantia nigra and the aggregation of α-synuclein into Lewy bodies. Existing therapies address motor dysfunction but do not halt progression of the disease. A still unresolved question is the biochemical pathway that modulates the outcome of protein misfolding and aggregation processes in PD. The molecular chaperone network plays an important defensive role against cellular protein misfolding and has been identified as protective in experimental models of protein misfolding diseases like PD. Molecular mechanisms underlying chaperone-neuroprotection are actively under investigation. Current evidence implicates a number of molecular chaperones in PD including Hsp25, Hsp70 and Hsp90, however their precise involvement in the neurodegenerative cascade is unresolved. The J protein family (DnaJ or Hsp40 protein family) has long been known to be important in protein conformational processes

Lifetime stress cumulatively programs brain transcriptome and impedes stroke recovery: benefit of sensory stimulation

Sherpa Romeo green journal, open accessPrenatal stress (PS) represents a critical variable affecting lifetime health trajectories, metabolic and vascular functions. Beneficial experiences may attenuate the effects of PS and its programming of health outcomes in later life. Here we investigated in a rat model (1) if PS modulates recovery following cortical ischemia in adulthood; (2) if a second hit by adult stress (AS) exaggerates stress responses and ischemic damage; and (3) if tactile stimulation (TS) attenuates the cumulative effects of PS and AS. Prenatally stressed and non-stressed adult male rats underwent focal ischemic motor cortex lesion and were tested in skilled reaching and skilled walking tasks. Two groups of rats experienced recurrent restraint stress in adulthood and one of these groups also underwent daily TS therapy. Animals that experienced both PS and AS displayed the most severe motor disabilities after lesion. By contrast, TS promoted recovery from ischemic lesion and reduced hypothalamic-pituitary-adrenal axis activity. The data also showed that cumulative effects of adverse and beneficial lifespan experiences interact with disease outcomes and brain plasticity through the modulation of gene expression. Microarray analysis of the lesion motor cortex revealed that cumulative PS and AS interact with genes related to growth factors and transcription factors, which were not affected by PS or lesion alone. TS in PS+AS animals reverted these changes, suggesting a critical role for these factors in activity-dependent motor cortical reorganization after ischemic lesion. These findings suggest that beneficial experience later in life can moderate adverse consequences of early programming to improve cerebrovascular health.Ye

Transgenerational programming of maternal behaviour by prenatal stress

Sherpa Romeo green journal. Open access, distributed under the terms of the Creative Commons Attribution (CC-BY) LicensePeripartum events hold the potential to have dramatic effects in the programming of physiology and behaviour of offspring and possibly subsequent generations. Here we have characterized transgenerational changes in rat maternal behaviour as a function of gestational and prenatal stress. Pregnant dams of the parental generation were exposed to stress from days 12-18 (F0-S). Their daughters and grand-daughters were either stressed (F1-SS, F2-SSS) or non-stressed (F1-SN, F2-SNN). Maternal antepartum behaviours were analyzed at a time when pregnant dams usually show a high frequency of tail chasing behaviours. F1-SS, F2-SNN and F2-SSS groups showed a significant reduction in tail chasing behaviours when compared with controls. The effects of multigenerational stress (SSS) slightly exceeded those of transgenerational stress (SNN) and resulted in absence of tail chasing behaviour. These findings suggest that antepartum maternal behaviour in rats is programmed by transgenerational inheritance of stress responses. Thus, altered antepartum maternal behaviour may serve as an indicator of an activated stress response during gestation.Ye

Ancestral exposure to stress epigenetically programs preterm birth risk and adverse maternal and newborn outcomes

Sherpa Romeo green journal: open accessAbstract Background: Chronic stress is considered to be one of many causes of human preterm birth (PTB), but no direct evidence has yet been provided. Here we show in rats that stress across generations has downstream effects on endocrine, metabolic and behavioural manifestations of PTB possibly via microRNA (miRNA) regulation. Methods: Pregnant dams of the parental generation were exposed to stress from gestational days 12 to 18. Their pregnant daughters (F1) and grand-daughters (F2) either were stressed or remained as non-stressed controls. Gestational length, maternal gestational weight gain, blood glucose and plasma corticosterone levels, litter size and offspring weight gain from postnatal days 1 to 30 were recorded in each generation, including F3. Maternal behaviours were analysed for the first hour after completed parturition, and offspring sensorimotor development was recorded on postnatal day (P) 7. F0 through F2 maternal brain frontal cortex, uterus and placenta miRNA and gene expression patterns were used to identify stress-induced epigenetic regulatory pathways of maternal behaviour and pregnancy maintenance. Results: Progressively up to the F2 generation, stress gradually reduced gestational length, maternal weight gain and behavioural activity, and increased blood glucose levels. Reduced offspring growth and delayed behavioural development in the stress cohort was recognizable as early as P7, with the greatest effect in the F3 offspring of transgenerationally stressed mothers. Furthermore, stress altered miRNA expression patterns in the brain and uterus of F2 mothers, including the miR-200 family, which regulates pathways related to brain plasticity and parturition, respectively. Main miR-200 family target genes in the uterus, Stat5b, Zeb1 and Zeb2, were downregulated by multigenerational stress in the F1 generation. Zeb2 was also reduced in the stressed F2 generation, suggesting a causal mechanism for disturbed pregnancy maintenance. Additionally, stress increased placental miR-181a, a marker of human PTB. Conclusions: The findings indicate that a family history of stress may program central and peripheral pathways regulating gestational length and maternal and newborn health outcomes in the maternal lineage. This new paradigm may model the origin of many human PTB causes.Ye

PD rats show increased levels of α-synuclein but not CSPα.

<p>Following left hemisphere injection of 2 µl of 4 mg/ml 6-OHDA, rats were tested for neurodegeneration and were dissected 27–33 days following injection. (<b>A</b>) 100 µg of total midbrain was fractionated, resolved by SDS-PAGE, transferred to nitrocellulose and α-synuclein was evaluated by Western blot. <b>(B</b>) α-synuclein, CSPα and SNAP25 expression levels of saline (control) or 6-OHDA lesion rats in the midbrain and striatum were evaluated by Western analysis using the monoclonal anti-α-synuclein antibody, the monoclonal anti-α-SNAP25 antibody or the anti-CSPα polyclonal antibody. <b>(C</b>) Western analysis of α-synuclein, CSPβ and SNAP25 for striatum, midbrain, cortex, prefrontal cortex, cerebellum and hippocampus of the left hemisphere of saline induced rats. Actin is shown as a loading control.</p

Tactile stimulation offset effects of cumulative stress in skilled walking ability.

<p><b>A,</b> A rat performing the ladder rung walking task; <b>B,</b> Walking error rate; <b>C,</b> Walking time and score. Prenatal stress prolonged the time to cross the ladder at baseline and post-lesion periods. Cumulative stress exaggerated the effects of ischemia in limb placement and inter-limb coordination. TS reduced limb placement errors and improved time measurements and scores. *p<0.05, **p<0.01, ***p<0.001.</p

Primers used for qRT-PCR gene expression profile validation.

<p>Primers used for qRT-PCR gene expression profile validation.</p

Cellular prion protein (PrP^C) does not change in PD rats.

<p>Following left hemisphere injection of 6-OHDA, rats were dissected 27–33 days post-lesion and 30 µg of homogenate isolated from the indicated brain regions was evaluated by Western analysis with the monoclonal antibody 6H4 (Prionics). (<b>A</b>) PrP^C expression in right and left striatum and hippocampus of saline and 6-OHDA lesion rats. (<b>B</b>) Western analysis of PrP^C in the striatum (STR), midbrain (MB), cortex (CTX), prefrontal cortex (PFC), cerebellum (CB) and hippocampus (HPC) of the left hemisphere of saline induced animals. (<b>C</b>) Quantification via Quantity One (BioRad) of the Western analysis. The quantification was carried out for eight individual saline treated rats.</p