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Objective: This study aimed to compare the incidence of dementia and all-cause mortality up to 20 years post-treatment in an index non-demented cohort between antipsychotic (AP) medication treatment and non-AP treatment groups., Methods: All patients in Kaiser Permanente Northern California with a major psychiatric diagnosis between 01/01/1996 and 12/31/2000, age ≥ 50 years, and without dementia diagnosis were included. The study cohort was divided into a "user group", patients treated with AP for ≥ 365 days (n = 1,829), and a "non-user group", propensity score-matched on age, sex, and race (n = 9,145). The association between AP exposure and dementia or mortality during the follow-up period (01/01/2001-12/31/2015) was evaluated using Cox proportional hazard models adjusted for psychiatric diagnosis, comorbidities, and other medications., Results: The user group had a hazard ratio (HR) of 2.2 (CI 1.8-2.7) for dementia and 1.3 (CI 1.2- 1.5) for death. The onset of dementia in the user group was significantly higher in patients aged ≤ 65 years (p < 0.001). The user group was sub-grouped into atypical, typical, and both; HR for dementia was 1.7 (CI 1.2-2.4), 2.5 (CI 1.9-3.1), and 1.8 (CI 1.4-2.4), respectively. Dementia and mortality were significantly higher in patients concurrently treated with benzodiazepine (HR 1.3; CI 1.2-1.5 and HR 1.4; CI 1.3-1.5) or tricyclic antidepressants (HR 1.2; CI 1.1-1.4 and HR 1.1; CI 1.0-1.2), respectively., Conclusion: Our preliminary results reveal an association between AP treatment and increased rates of both dementia and mortality. Future research is needed to substantiate our current findings., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Neuropsychiatric disorders (including dementia) have high personal, family, and social costs. Although many neuropsychiatric disorders share common patterns of symptoms and treatments, there are no validated biomarkers that define the underlying molecular mechanisms in the central nervous system (CNS). We hypothesize that there are early and common molecular changes in the CNS that will serve as sensitive indicators of CNS molecular stress and that will be predictive of neuropathological changes resulted in increasing the risk for neuropsychiatric diseases. Using the rodent model, we showed that systemic exposure to three diverse CNS stressors with different mechanisms of action (ketamine, low-dose and high-dose ionizing radiation, interferon-α) induced the expression of troponin T1 (Tnnt 1) within hours in adult mouse brain tissue. Tnnt 1 expression was induced in neuronal (not glial) cells, the hippocampal zone of neurogenesis, cerebral cortex, amygdale, and choroid plexus, which are important CNS locations in behavior and mental health. We also identified nine neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue for hours after low-dose irradiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Our studies provide new molecular information on shared mechanisms and expression profiles of diverse neuropsychiatric disorders. This knowledge will be fundamental for developing molecular signatures of early CNS stress biomarker for early diagnosis and treatment of neuropsychiatric diseases.

We previously showed that the expression of troponin T1 (Tnnt 1) was induced in the central nervous system (CNS) of adult mice 30min after treatment with ketamine, a glutamate N-methyl-D-aspartic acid (NMDA) receptor antagonist. We hypothesized that Tnnt 1 expression may be an early molecular biomarker of stress response in the CNS of mice. To further evaluate this hypothesis, we investigated the regional expression of Tnnt 1 in the mouse brain using RNA in situ hybridization 4h after systemic exposure to interferon-alpha (IFN-alpha) and gamma ionizing radiation, both of which have be associated with wide ranges of neuropsychiatric complications. Adult B6C3F1 male mice were treated with either human IFN-alpha (a single i.p. injection at 1 x 10(5)IU/kg) or whole body gamma-radiation (10cGy or 2Gy). Patterns of Tnnt 1 transcript expression were compared in various CNS regions after IFN-alpha, radiation and ketamine treatments (previous study). Tnnt 1 expression was consistently induced in pyramidal neurons of cerebral cortex and hippocampus after all treatment regimens including 10cGy of ionizing radiation. Regional expression of Tnnt 1 was induced in Purkinje cells of cerebellum after ionizing radiation and ketamine treatment; but not after IFN-alpha treatment. None of the three treatments induced Tnnt 1 expression in glial cells. The patterns of Tnnt 1 expression in pyramidal neurons of cerebral cortex and hippocampus, which are both known to play important roles in cognitive function, memory and emotion, suggest that the expression of Tnnt 1 may be an early molecular biomarker of induced CNS stress.

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy and environmental nuclear contamination as well as for Earth-orbit and space missions. Analyses of transcriptome profiles of mouse brain tissue after whole-body irradiation showed that low-dose exposures (10 cGy) induced genes not affected by high-dose radiation (2 Gy) and that low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues and pathways that were specific for brain tissue. Low-dose genes clustered into a saturated network (P < 10(-53)) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified nine neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose irradiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down-regulated in normal human aging and Alzheimer's disease.

The glutamatergic system has been implicated in neuropsychiatric disorders, such as schizophrenia, bipolar disorder and Alzheimer's disease, which also have a high prevalence of metabolic syndrome. Treatment with ketamine, a non-competitive glutamate N-methyl-d-aspartic acid (NMDA) receptor antagonist, is known to have paradoxical effects of neuroprotection and neurotoxicity. We investigated gene expression in brain tissue of adult mice treated with ketamine to characterize the expression profiles and to identify the affected metabolic pathways. Adult male mice were treated by a single intraperitoneal (i.p.) injection of either s(+)ketamine (80 mg/kg) or distilled water (as the control). Fifty genes were differentially expressed in ketamine-treated mouse brains compared with control mice using oligonucleotide microarray analysis, and the expression of Troponin T1 (Tnnt1) gene was consistently elevated (2- to 4-fold) (p<0.001). Ketamine-induced Tnnt1 expression was confirmed and characterized using RNA in situ hybridization techniques in paraffin embedded brain tissue sections. Tnnt1 expression was induced in the granule layer of the hippocampus, amygdala, hypothalamus, Purkinje cells of cerebellum (p<0.0001), and cerebral cortex. Tnnt1 gene is known to interact directly with FoxO1, which is involved in multiple peripheral metabolic pathways and central energy homeostasis. Our findings suggest that the induction of Tnnt1 gene expression in adult mouse brains by ketamine may illustrate the genes involved in the metabolic syndromes observed in neuropsychiatric disorders.

A couple with normal somatic karyotypes had four consecutive trisomic pregnancies, each involving a different chromosome, of which two children were liveborn with confirmed paternal-origin trisomies. The apparently healthy father produced abnormally high frequencies of disomic sperm for each of the four chromosomes involved in the trisomic pregnancies (P< 0.003, by sperm fluorescence in situ hybridization (FISH)). His elevated sperm aneuploidies persisted over a 2-year period and affected all chromosomes evaluated, suggesting that he had a genome-wide defect in meiotic disjunction. He also had the highest frequencies of aneuploid sperm reported for any healthy man to date. His frequencies of aneuploid sperm were comparable to the peak frequencies of the transient responses reported in some cancer patients after receiving aneugenic chemotherapies. These findings indicate that apparently healthy men can produce abnormally high frequencies of sperm aneuploidies that suggest that this condition may contribute to recurrent trisomic pregnancies.

The objective of this research was to determine whether Novantrone, Oncovin, Velban, and Prednisone (NOVP) combination chemotherapy for Hodgkin's disease increases the frequencies of the specific types of aneuploid sperm that might elevate the risk of fathering a child with one of the major clinical aneuploidy syndromes, i.e., Down (disomy 21 sperm), Edward (disomy 18 sperm), Turner (nullisomy sex sperm), XYY (disomy Y sperm), triple X (disomy X sperm), or Klinefelter (XY sperm). A four-chromosome multicolor sperm fluorescence in-situ hybridization assay that simultaneously evaluates chromosomes 18, 21, X, and Y was applied to semen provided by four healthy men and to repeated samples of eight Hodgkin's disease patients before treatment, 35-50 days after treatment to examine the effects of treatment on male meiotic cells, and 1-2 years after treatment to measure the persistence of damage. There were chromosome-specific variations in baseline frequencies and significant inductions of all of the detectable types of sperm aneuploidies: XY sperm (14-fold increase), disomy 18 (7-fold), nullisomy sex (3-fold), disomy 21 (3-fold), and disomy X and Y (approximately 2-fold each). Disomy 21 was about twice as frequent as disomy 18, and neither showed a preferential segregation with a sex chromosome. Extrapolating across the genome, approximately 18% of sperm carried a numerical abnormality after NOVP treatment of meiotic cells. Induced effects did not persist to 1-2 years after treatment, suggesting that persistent spermatogonial stem cells were not sensitive to NOVP. These findings establish the hypothesis that conception shortly after certain chemotherapies can transiently increase the risks of fathering aneuploid pregnancies that terminate during development or result in the birth of children with major human aneuploidy syndromes.

A pair of multicolor FISH assays (X-Y-21 and A-M-16) was developed for human sperm to simultaneously measure sex ratios; aneuploidies involving chromosomes 1, 16, 21, X, and Y; meiotic diploidies; and structural aberrations involving chromosome 1p. Sex ratios in sperm were not significantly different from unity among healthy men. Baseline frequencies of disomic sperm for chromosomes 1, 8, and 21 were similar (6.7 per 10(4) sperm, 95% CI of 5.6-8.1), suggesting that among these three chromosomes, chromosome 21 was not especially prone to nondisjunction. Frequencies of disomy 16 sperm were significantly lower, however (3.5 per 10(4) sperm, 95% CI of 2.0-6.2; P < 0.02). The baseline frequencies of sperm disomy by FISH for chromosomes 16 and 21 were validated against aneuploidy data obtained by the hamster-egg technique for human sperm cytogenetics. The frequencies of X-X, Y-Y, X-Y ("Klinefelter") sperm and sex-null ("Turner") sperm were 5.5, 5.1, 5.5, and 7.8 per 10(4) sperm, respectively. For chromosomes 16 and 21, the frequencies of nullisomic and disomic sperm were similar, suggesting that gain and loss events occurred symmetrically. However, more gain than loss was reported for chromosomes 1, X, and Y. The frequency of MI and MII diploid sperm (with flagella) was approximately 12 per 10(4) (range 8.3-16.7 per 10(4) sperm). Based on flagella data, the frequency of somatic cells in the semen was estimated to be approximately 1.8 per 10(4) sperm. Loss or gain of a portion of chromosome-arm 1p occurred in 5.5 per 10(4) sperm, and the percentage of sperm carrying structural aberrations within the haploid genome as calculated from FISH (1.4%), was similar to that obtained with the hamster-egg technique. These complementary sperm FISH assays have promising applications in studies of chromosomally abnormal sperm after exposure to occupational, medical, and environmental toxicants.

A multicolor fluorescence in situ hybridization (FISH) method was developed to detect aneuploidy and diploidy in epididymal sperm of rats using DNA probes specific for chromosomes 4 and Y. Fourteen healthy young-adult rats from three strains were evaluated: inbred Fisher 344/N/ehs, outbred Sprague-Dawley, and outbred WU Wistar/CPB. The hybridization efficiency of the FISH procedure was > 99.9%, the sex-ratio in sperm was approximately 1 as expected, and there was no significant variation among two independent scorers. No significant variations were detected within or among strains in the frequencies of sperm disomy for chromosome 4 (1-6.5 per 10,000 cell per animal) or the Y chromosome (0-2.5 per 10,000 cells per animal). There was a trend toward increased variation among Wistar rats. The frequencies of sperm-carrying hyper- and hypohaploidy for chromosome 4 were similar, suggesting a symmetrical mechanism of chromosome gain and loss during meiosis. The frequencies of Y-Y-4-4 sperm, which represent genomic meiosis II errors, did not differ significantly across strains (0.1-0.7 per 10,000 cells per strain). This FISH method for detecting aneuploidy in rat epididymal sperm provides a promising interspecies biomarker of male germ cell aneuploidy and introduces the rat as an animal model for investigating the heritable risk to offspring associated with paternal genotype, physiology, and exposure to environmental mutagens. There appear to be no significant differences among young healthy rats, mice, and men in the baseline frequencies of sperm with Y chromosomal disomy, the only chromosome for which data currently exists for all three species.

Multi-color fluorescence in situ hybridization (FISH) was employed to investigate variations in the frequency of aneuploid spermatids produced by males derived from three separate lines of Robertsonian translocations in mice: Rb(2.8)2Lub, Rb(8.12)22Lub, and Rb(8.14)16Rma, each with one arm involving chromosome 8. The DNA probes used were specific for repetitive sequences on chromosomes 8 and X. Heterozygous males for these Robertsonian translocations produced approximately 1% of spermatids with hyperhaploid for chromosome 8. which was > 80 times higher than the frequency of sperm hyperhaploid for chromosome X within the same animals; consistent elevations in chromosome-8 sperm disomy were observed among lines. In addition, approximately 25% higher fractions of sperm aneuploidy were observed when the Robertsonian translocation was inherited from the father rather than from the mother (p = 0.009). These findings illustrate the sensitivity of the FISH procedure for detecting small differences in the hyperhaploidy in male germ cells and suggest that imprinted factors may influence sperm aneuploidy.

Both structural and numerical chromosome aberrations in sperm represent important categories of paternally transmitted genetic damage. Therefore, a new multiprobe fluorescence in situ hybridization (FISH) method, using DNA probes for three targets (centromere and telomere of chromosome 1, centromere of chromosome 8), was developed to detect human sperm carrying three types of chromosomal defects: (1) terminal duplications or deletions in chromosome 1p, (2) aneuploidy involving chromosomes 1 or 8, and (3) diploidy. Baseline frequencies were determined for three healthy donors who had been previously evaluated for sperm cytogenetics by the human-sperm/hamster-oocyte cytogenetic technique (hamster technique). Among approximately 120,000 sperm analyzed by the new FISH method, the average baseline frequencies of sperm carrying telomeric duplications and deletions of 1p were 3.2 +/- 1.9 and 2.9 +/- 3.6 per 10(4), respectively. Diploid sperm was found in an average frequency of 6.6 +/- 4.0 per 10(4). Average frequencies of disomic sperm for chromosomes 1 or 8 were 1.7 +/- 2.2 and 1.9 +/- 2.3 per 10(4), respectively. Inter-individual differences were observed for deletions of 1p but not for the other sperm phenotypes. A good correlation was obtained between the frequencies of sperm with structural chromosome aberrations detected with the new assay and the frequency of sperm carrying premeiotic or meiotic cytogenetic damage detected with the hamster technique. The observed levels of numerical aberrations with the new FISH assay were within range of the baseline frequencies reported by the hamster technique. The newly developed FISH assay has promising applications in genetic, clinical, physiological and toxicological studies.

The chromosomal effects of chloral hydrate (CH) on germ cells of male mice were investigated using two methods to detect and characterize spermatid micronuclei (SMN); (a) anti-kinetochore immunofluorescence (SMN-CREST) and (b) multicolor fluorescence in situ hybridization with DNA probes for centromeric DNA and repetitive sequences on chromosome X (SMN-FISH). B6C3F1 mice received single intraperitoneal (i.p.) injections of 82.7, 165.4, or 413.5 mg/kg and round spermatids were sampled at three time intervals representing cells treated in late meiosis, early meiosis, or as spermatogonial stem cells. No increases in the frequencies of SMN were detected for cells treated during meiosis using either SMN-CREST or SMN-FISH methods. After spermatogonial stem-cell treatment, however, elevated frequencies of SMN were detected by both methods. With SMN-FISH, dose trends were observed both in the frequencies of spermatids containing micronuclei and in the frequency of spermatids carrying centromeric label. These findings corroborate the recent report by Allen and colleagues [Allen JW et al.(1994): Mutat. Res. 323:81-88] that CH treatment of spermatogenic stem cells induced SMN. Furthermore, our findings suggest that chromosomal malsegregation or loss may occur in spermatids long after CH treatment of stem cells. Further studies are needed to understand the mechanism of action of the CH effect on stem cells and to determine whether similar effects are induced in human males treated with CH.