Effects of orbital space flight on vestibular reflexes and perception

Young, Laurence R.

doi:10.1016/0094-5765(95)00125-5

Cited by 5 publications

(2 citation statements)

References 11 publications

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“…For example at day 2 after launch and at day 1 after re‐entry, an increase in the number of cells immunopositive for immediate early genes (Fos and Fos‐related antigen) was observed in the medial, inferior, superior and spinal vestibular nuclei of rats (Gustave Dit Duflo et al ., 2000; Pompeiano et al ., 2001a). Moreover, it was shown that space flights affect vestibular reflexes in humans (Young, 1995). Because vestibular nuclei send indirect projections to the hippocampus (Stackman et al ., 2002), it is possible that conditions that directly affect the vestibular system (i.e.…”

Section: Discussionmentioning

confidence: 99%

Hippocampal gene expression is modulated by hypergravity

Signore

Mandillo

Rizzo

et al. 2004

Eur J of Neuroscience

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We used the cDNA microarray technique to monitor simultaneously possible changes induced by hypergravity in the expression level of thousands of hippocampal genes. We tested the mRNA level of about 5000 genes in the hippocampus of mice subjected to 1.09 g (1g) or to 1.85 g (2g) for five repeated 1-h daily rotations in a centrifuge (g = 9.81 m/s2). Data were compared with those obtained for mice kept stationary (C). The ratios 1g/C and 2g/C identified genes affected by rotation and rotation + hypergravity, respectively, whereas 2g/1g ratio identified those affected by hypergravity. We found that about 200 genes were affected by rotation and/or rotation + hypergravity. Almost all the genes affected by rotation + hypergravity were up-regulated, only five being down-regulated. The modulated genes code for proteins involved in a wide range of cellular functions (DNA/RNA metabolism, protein processing, intermediate metabolism, cytoskeleton and motility, cell cycle and apoptosis, signal transduction, neuronal structure/function), suggesting that rotation + hypergravity may affect several aspects of the hippocampal function in order to compensate for environmental changes. Six genes directly or indirectly involved in synaptic transmission and plasticity (proSAAS, neuroblastoma ras oncogene, ESTs moderately similar to thymosin beta-10, syndet, inhibin beta E and Ngfi-A binding protein 2) were found to be significantly modulated by hypergravity and unaffected or only slightly affected by rotation. The modulation by hypergravity of these genes suggests that this stimulus might induce plastic remodelling of the hippocampal circuits, possibly both at structural and functional level.

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Section: Discussionmentioning

confidence: 99%

Hippocampal gene expression is modulated by hypergravity

Signore

Mandillo

Rizzo

et al. 2004

Eur J of Neuroscience

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“…The effect of hypergravity has been studied in mice after rotation in a centrifuge apparatus, and the expression of genes in the hippocampus was found to be significantly modulated (Del Signore et al 2004) including those involved in spatial learning (Cavallaro et al 2002). In other studies it has been shown that space flight or exposure to hypergravity conditions affect the vestibular system in rats (Pompeiano et al 2004; Uno et al 2002) and the vestibular reflex in humans (Young 1995). Hypergravity can also affect synaptic contacts, since in fish a significant synaptic ultrastructural alteration after exposure to hypergravity has been reported (Rahmann et al 1992).…”

Section: Introductionmentioning

confidence: 93%

Effect of microgravity on gene expression in mouse brain

Frigeri

Iacobaş

et al. 2008

Exp Brain Res

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Changes in gravitational force such as that experienced by astronauts during space flight induce a redistribution of fluids from the caudad to the cephalad portion of the body together with an elimination of normal head-to-foot hydrostatic pressure gradients. To assess brain gene profile changes associated with microgravity and fluid shift, a large-scale analysis of mRNA expression levels was performed in the brains of 2-week control and hindlimb-unloaded (HU) mice using cDNA microarrays. Although to different extents, all functional categories displayed significantly regulated genes indicating that considerable transcriptomic alterations are induced by HU. Interestingly, the TIC class (transport of small molecules and ions into the cells) had the highest percentage of upregulated genes, while the most down-regulated genes were those of the JAE class (cell junction, adhesion, extracellular matrix). TIC genes comprised 16% of those whose expression was altered, including sodium channel, nonvoltage-gated 1 beta (Scnn1b), glutamate receptor (Grin1), voltagedependent anion channel 1 (Vdac1), calcium channel beta 3 subunit (Cacnb3) and others. The analysis performed by Gene-MAPP revealed several altered protein classes and functional pathways such as blood coagulation and immune response, learning and memory, ion channels and cell junction. In particular, data indicate that HU causes an alteration in hemostasis which resolves in a shift toward a more hyper-coagulative state with an increased risk of venous thrombosis. Furthermore, HU treatment seems to impact on key steps of synaptic plasticity and learning processes.

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