No abstract

The purpose of the present study was to evaluate the relationship between sleep disturbances and depression in the Japanese elderly. Methods: These investigations in the Japanese elderly were carried out with the Geriatric Depression Scale, the Pittsburgh Sleep Quality Index, and questions on restless legs syndrome and nocturnal eating disorder. A total of 2023 people (male: 1008; female: 1015; average age: 74.2 ± 6.3 years) were analyzed by c 2 test and simple and multiple logistic regression. The prevalence of sleep disturbance was 37.3% and that of depression was 31.3%. Female gender and/or older ( ≥ 75 years) age were significantly associated with depression. Characteristics in depressive elderly were poor sleep efficiency, sleep disturbances due to difficulty of initiating sleep (DIS), breathing discomfort, coldness and pain, poor subjective sleep quality and lack of enthusiasm for activities. Sleep disturbances due to using the bathroom, breathing discomfort and coldness and long sleep latency were associated with depression in younger (65-74 years) men. Sleep disturbance due to DIS was associated with depression in older ( ≥ 75 years) men. Sleep disturbance due to pain was associated with depression in younger and older women. Poor sleep efficiency was associated with depression in older women. Poor subjective sleep quality was associated with depression in younger and older men and younger women. Lack of enthusiasm was associated with depression in younger and older men and older women. Restless legs syndrome was statistically significantly associated with depression in younger men. It is concluded that sleep disturbance and depression among the Japanese elderly are closely related symptoms. The features of sleep disturbance with depression differed with sex and age.

The Drosophila pericentrin-like protein has been shown to be essential for the formation of the sensory cilia of chemosensory and mechanosensory neurons by mutant analysis in flies, while the in vivo function of pericentrin, a well-studied mammalian centrosomal protein related to microcephalic primordial dwarfism, has been unclear. To determine whether pericentrin is required for ciliogenesis in mammals, we generated and analyzed mice with a hypomorphic mutation of Pcnt encoding the mouse pericentrin. Immunofluorescence analysis demonstrated that olfactory cilia of chemosensory neurons in the nasal olfactory epithelium were malformed in the homozygous mutant mice. On the other hand, the assembly of motile and primary cilia of non-neuronal epithelial cells and the formation of sperm flagella were not affected in the Pcnt-mutant mice. The defective assembly of olfactory cilia in the mutant was apparent from birth. The mutant animals displayed reduced olfactory performance in agreement with the compromised assembly of olfactory cilia. Our findings suggest that pericentrin is essential for the assembly of chemosensory cilia of olfactory receptor neurons, but it is not globally required for cilia formation in mammals.

In the rodent brain, certain G protein-coupled receptors and adenylyl cyclase type 3 are known to localize to the neuronal primary cilium, a primitive sensory organelle protruding singly from almost all neurons. A recent chemical screening study demonstrated that many compounds targeting dopamine receptors regulate the assembly of Chlamydomonas reinhardtii flagella, structures which are analogous to vertebrate cilia. Here we investigated the effects of dopaminergic inputs loss on the architecture of neuronal primary cilia in the rodent striatum, a brain region that receives major dopaminergic projections from the midbrain. We first analyzed the lengths of neuronal cilia in the dorsolateral striatum of hemi-parkinsonian rats with unilateral lesions of the nigrostriatal dopamine pathway. In these rats, the striatal neuronal cilia were significantly longer on the lesioned side than on the non-lesioned side. In mice, the repeated injection of reserpine, a dopamine-depleting agent, elongated neuronal cilia in the striatum. The combined administration of agonists for dopamine receptor type 2 (D2) with reserpine attenuated the elongation of striatal neuronal cilia. Repeated treatment with an antagonist of D2, but not of dopamine receptor type 1 (D1), elongated the striatal neuronal cilia. In addition, D2-null mice displayed longer neuronal cilia in the striatum compared to wild-type controls. Reserpine treatment elongated the striatal neuronal cilia in D1-null mice but not in D2-null mice. Repeated treatment with a D2 agonist suppressed the elongation of striatal neuronal cilia on the lesioned side of hemi-parkinsonian rats. These results suggest that the elongation of striatal neuronal cilia following the lack of dopaminergic inputs is attributable to the absence of dopaminergic transmission via D2 receptors. Our results provide the first evidence that the length of neuronal cilia can be modified by the lack of a neurotransmitter's input.