Clock-controlled arylalkylamine N-acetyltransferase (aaNAT) regulates circadian rhythms of locomotor activity in the American cockroach, Periplaneta americana, via melatonin/MT2-like receptor.

Melatonin (MEL) orchestrates daily and seasonal rhythms (eg, locomotion, sleep/wake cycles, and migration among other rhythms) in diverse organisms. We investigated the effects of pharmacological doses (0.03-1 mM) of exogenous MEL intake in the cockroach, Periplaneta americana, on locomotor activity.

Northward expansion of the bivoltine life cycle of the cricket over the last four decades.

Recent climate warming has affected some life-history traits of insects, including voltinism and body size. The magnitude of changes in these traits may differ latitudinally within a species because of the differing lengths of season available for growth. The present study aims to estimate the change in voltinism of the lawn ground cricket, Polionemobius mikado (Shiraki) (Orthoptera: Trigonidiidae), over the last four decades by comparing the body size between adults collected from a wide range of latitudes in Japan in recent years (2015-2017) and those collected four decades ago (1969-1976).

Day-to-day variations in the amplitude of the soil temperature cycle and impact on adult eclosion timing of the onion fly.

The onion fly Delia antiqua advances its eclosion timing with decreasing temperature amplitude to compensate for a depth-dependent phase delay of the zeitgeber. To elucidate whether or not naturally occurring day-to-day variations in the amplitude of soil temperature cycle disturb this compensatory response, we monitored daily variations in the temperature amplitude in natural soils and evaluated the impact on adult eclosion timing. Our results indicated that both median and variance of the soil temperature amplitude become smaller as depth increases.

Oxidative Stress and Nitric Oxide in Autism Spectrum Disorder and Other Neuropsychiatric Disorders.

The etiology of autism spectrum disorder (ASD) remains unclear; however, the toxic environmental exposure to oxidative stress has been suggested to play an important role in its pathogenesis. A loss of balance between oxidative stress and antioxidant capacity produces an excess of reactive nitrogen species (RNS) such as nitric oxide (NO). Polyunsaturated fatty acids (PUFAs), particularly arachidonic acid, docosahexaenoic acid and eicosapentaenoic acid, are closely related to NO and NO synthase.

Temperature cycle amplitude alters the adult eclosion time and expression pattern of the circadian clock gene period in the onion fly.

Soil temperature cycles are considered to play an important role in the entrainment of circadian clocks of underground insects. However, because of the low conductivity of soil, temperature cycles are gradually dampened and the phase of the temperature cycle is delayed with increasing soil depth. The onion fly, Delia antiqua, pupates at various soil depths, and its eclosion is timed by a circadian clock.

Competitive Interaction Between Plasma Omega-3 Fatty Acids and Arachidonic Acid is Related to Down-Regulation of A Signaling Mediator.

Autism spectrum disorders (ASD) may be attributed to altered composition of polyunsaturated fatty acids. We examined the relationships between the plasma ratios of docosahexaenoic acid (DHA)/arachidonic acid (AA) and eicosapentaenoic acid (EPA)/AA, and biomarkers of AA-related signaling mediators, i.e.

Increased ω-3 polyunsaturated fatty acid/arachidonic acid ratios and upregulation of signaling mediator in individuals with autism spectrum disorders.

Aims: The investigation of links between the ratio of omega-3/omega-6 PUFAs and neuronal signaling is a research priority in autism spectrum disorders (ASD).

Main Methods: We examine the relationships between the plasma ratios of docosahexaenoid acid (DHA)/arachidonic acid (AA) and eicopentaenoic acid (EPA)/AA and biomarkers of AA-related signaling mediators such as ceruloplasmin, transferrin and superoxide dismutase, in the behavioral symptoms of 28 individuals with ASD (mean age 13.5±4.

Common features in diverse insect clocks.

This review describes common features among diverse biological clocks in insects, including circadian, circatidal, circalunar/circasemilunar, and circannual clocks. These clocks control various behaviors, physiological functions, and developmental events, enabling adaptation to periodic environmental changes. Circadian clocks also function in time-compensation for celestial navigation and in the measurement of day or night length for photoperiodism.

Down-regulation of a signaling mediator in association with lowered plasma arachidonic acid levels in individuals with autism spectrum disorders.

Previous studies have indicated that the altered composition of polyunsaturated fatty acids (PUFAs) might contribute to the pathophysiology of autism spectrum disorder (ASD). We examined the relationship between the plasma fatty acid levels, expressed as μg/ml, and the plasma levels of biomarkers of AA-related signaling mediators, such as ceruloplasmin, transferrin and superoxide dismutase, and assessed the behavioral symptoms of 30 individuals with ASD (mean age, 13.6 ± 4.

Eicosanoids Derived From Arachidonic Acid and Their Family Prostaglandins and Cyclooxygenase in Psychiatric Disorders.

Arachidonic acid (AA)-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of a wide variety of physiological responses and pathological processes, and control important cellular processes. AA can be converted into biologically active compounds by metabolism by cyclooxygenases (COX).

Brain-midgut cross-talk and autocrine metabolastat via the sNPF/CCAP negative feed-back loop in the American cockroach, Periplaneta americana.

Immunohistochemical reactivities against short neuropeptide F (sNPF-ir) and crustacean cardioactive peptide (CCAP-ir) were detected in both the brain-subesophageal ganglion (Br-SOG) and midgut epithelial cells of the male American cockroach, Periplaneta americana. Four weeks of starvation increased the number of sNPF-ir cells and decreased the CCAP-ir cells in the Br-SOG, whereas refeeding reversed these effects. The contents of sNPF in the Br-SOG, midgut and hemolymph titer decreased in response to an injection of CCAP into the hemocoel of normally fed male cockroaches, while CCAP titers/contents decreased in response to an injection of sNPF.

Mitochondrial Dysfunction and Its Relationship with mTOR Signaling and Oxidative Damage in Autism Spectrum Disorders.

Mitochondria are organelles that play a central role in processes related to cellular viability, such as energy production, cell growth, cell death via apoptosis, and metabolism of reactive oxygen species (ROS). We can observe behavioral abnormalities relevant to autism spectrum disorders (ASDs) and their recovery mediated by the mTOR inhibitor rapamycin in mouse models. In Tsc2(+/-) mice, the transcription of multiple genes involved in mTOR signaling is enhanced, suggesting a crucial role of dysregulated mTOR signaling in the ASD model.

[Useful pharmacologic treatment in impaired social interaction in autism spectrum disorders].

It is important to note that risperidone solution, intranasal administration of oxytocin, and dietary supplementation with large doses of arachidonic acid added to docosahexaenoic acid (DHA) have been reported to improve impaired social interaction. In addition, atypical antipsychotics aripiprazole and SSRI fluvoxamine were useful in treating some aspects of social relatedness or the core deficits of communication and socialization. The evaluation of treatments for ASD should be directed at neurobiological targets known to be important in the brain's response to abnormal developmental trajectories or toward enhancing plasticity during the highly sensitive period in gene-environment interaction (epigenetic mechanism).

Circannual rhythm in the varied carpet beetle, Anthrenus verbasci.

Although circannual rhythms controlling different physiological processes and various aspects of behavior have been reported in numerous organisms, our understanding of the underlying biological mechanisms is still quite limited. We examined the mechanisms controlling the circannual pupation rhythm of the varied carpet beetle, Anthrenus verbasci. This rhythm is self-sustainable, exhibits temperature compensation of the periodicity, and is entrainable to environmental changes.

Effects of large doses of arachidonic acid added to docosahexaenoic acid on social impairment in individuals with autism spectrum disorders: a double-blind, placebo-controlled, randomized trial.

Autism spectrum disorders are a neurodevelopmental disorders with reduced cortical functional connectivity relating to social cognition. Polyunsaturated fatty acids arachidonic acid (ARA) and docosahexaenoic acid (DHA) may have key role in brain network maturation. In particularly, ARA is important in signal transduction related to neuronal maturation.

Interacting effect of thermoperiod and photoperiod on the eclosion rhythm in the onion fly, Delia antiqua supports the two-oscillator model.

Daily light and temperature cycles entrain adult eclosion rhythms in many insect species, but little is known about their interaction. We studied this problem in the onion fly, Delia antiqua. Pupae were subjected to various combinations of a photoperiod of 12L:12D and thermoperiods.

Comparison of the circadian eclosion rhythm between non-diapause and diapause pupae in the onion fly, Delia antiqua: the change of rhythmicity.

When pupae of Delia antiqua were transferred to constant darkness (DD) from light-dark (LD) cycles or constant light (LL), the sensitivity to light of the circadian clock controlling eclosion increased with age. The daily rhythm of eclosion appeared in both non-diapause and diapause pupae only when this transfer was made during late pharate adult development. When transferred from LL to DD in the early pupal stage, the adult eclosion was weakly rhythmic in non-diapause pupae but arrhythmic in diapause pupae.

Comparison of the circadian eclosion rhythm between non-diapause and diapause pupae in the onion fly, Delia antiqua.

The influence of pupal diapause on adult eclosion rhythm of Delia antiqua was investigated. When non-diapause and diapause pupae were exposed to various photoperiods at 15, 20 and 25 degrees C, both of them emerged as adults close to the light-on time, but the phase of eclosion varied with photoperiod and temperature. Moreover, there was a significant difference in the eclosion time between non-diapause and diapause pupae; the eclosion peak of diapause pupae was earlier than that of non-diapause pupae.

Comparison of the circadian eclosion rhythm between non-diapause and diapause pupae in the onion fly, Delia antiqua: the effect of thermoperiod.

When non-diapause and diapause pupae of Delia antiqua were exposed to various thermoperiods where thermophase (T) was 25 degrees C and the cryophase (C) was 15 or 20 degrees C (TC(15) or TC(20)) in constant darkness (DD), the majority of both types of flies emerged before the rise in temperature. Eclosion time was delayed at the lower cryophase temperature. Moreover, there was a significant difference in the time of adult eclosion between non-diapause and diapause pupae; diapause pupae eclosed earlier than non-diapause pupae.

Effects of photoperiod and aging on locomotor activity rhythms in the onion fly, Delia antiqua.

At photoperiods longer than 8h per 24h, adults of the day-active onion fly Delia antiqua showed a major peak of locomotor activity in the late photophase and also bursts of activity induced by lights-on or lights-off. At shorter photoperiods the activity peaks fused. After transfer from long photoperiods to constant darkness (DD), the rhythm free-ran, but only the major peak persisted.

Electrochemical determination for enzymic production of ultimate carcinogen from tryptophan pyrolysate by rat hepatic microsomes.

This study established a rapid and sensitive method of determining the level of the ultimate carcinogen from 3-amino-1-methyl-5H-prido[4,3-b]indole (Trp-P-2) produced by rat hepatic microsomes. An electrochemical detector (ECD) used with high-performance liquid chromatography (HPLC) gave a linear calibration curve for synthetic N-hydroxy-Trp-P-2 (the ultimate carcinogenic form) at concentrations ranging between 0.3 and 340 pmol.