Choline Transporter regulates olfactory habituation via a neuronal triad of excitatory, inhibitory and mushroom body neurons

Choline Metabolites Reverse Differentially the Habituation Deficit and Elevated Memory of Tau Null Drosophila

Impaired neuronal plasticity and cognitive decline are cardinal features of Alzheimer's disease and related Tauopathies. Aberrantly modified Tau protein and neurotransmitter imbalance, predominantly involving acetylcholine, have been linked to these symptoms. In Drosophila, we have shown that dTau loss specifically enhances associative long-term olfactory memory, impairs foot shock habituation, and deregulates proteins involved in the regulation of neurotransmitter levels, particularly acetylcholine. Interestingly, upon choline treatment, the habituation and memory performance of mutants are restored to that of control flies. Based on these surprising results, we decided to use our well-established genetic model to understand how habituation deficits and memory performance correlate with different aspects of choline physiology as an essential component of the neurotransmitter acetylcholine, the lipid phosphatidylcholine, and the osmoregulator betaine. The results revealed that the two observed phenotypes are reversed by different choline metabolites, implying that they are governed by different underlying mechanisms. This work can contribute to a broader knowledge about the physiologic function of Tau, which may be translated into understanding the mechanisms of Tauopathies.

Tertiary students maintaining control over depression, anxiety, and stress during the pandemic—An emerging market perspective

The higher education sector was affected by this pandemic, managing enduring challenges since early 2020. Institutions of higher learning (IHL) are prepared to address unsurmountable challenges to ensure that students are not deceived and are being given the proper nurture, coupled with adherence to syllabuses. Simultaneously, the COVID-19 pandemic has caused unscrupulous pressure on students of these institutions. The psychological waves are creating mammoth consequences, affecting the beneficiaries of the higher education system and their families. In recent years, with limited studies on psychological impact among tertiary students on a cross-country basis, general self-efficacy, and the degree of coping strategies, we were motivated to investigate the degree of depression, anxiety, and stress (DAS), among this cohort of students encompassing the pre-university/Diploma, 1st–4th-year undergraduate, and postgraduate students from private universities in Malaysia, Indonesia, India, Southern Africa, and China, representing the emerging economies. A cross-sectional survey was conducted, followed by quantitative analysis. The objective of this study was to recognize whether there is a relationship between the psychological impact of DAS and the coping strategies adopted by the undergraduate students responding during the lockdown. The findings of this study revealed that with a sample size of 397, DAS lacked any severe impact on students across gender, country, household income, and level of education. DAS was established to be well managed with a coping strategy and self-efficacy established. This study resulted in a deeper understanding of DAS among undergraduates in emerging economies and their degree of coping behavior, providing a glimpse of the approach of millennials to handle DAS during the pandemic.

Loss of the Schizophrenia-Linked Furin Protein from Drosophila Mushroom Body Neurons Results in Antipsychotic-Reversible Habituation Deficits

Habituation is a conserved adaptive process essential for incoming information assessment, which drives the behavioral response decrement to recurrent inconsequential stimuli and does not involve sensory adaptation or fatigue. Although the molecular mechanisms underlying the process are not well understood, habituation has been reported to be defective in a number of disorders including schizophrenia. We demonstrate that loss of furin1, the Drosophila homolog of a gene whose transcriptional downregulation has been linked to schizophrenia, results in defective habituation to recurrent footshocks in mixed sex populations. The deficit is reversible by transgenic expression of the Drosophila or human Furin in adult α'/β' mushroom body neurons and by acute oral delivery of the typical antipsychotic haloperidol and the atypical clozapine, which are commonly used to treat schizophrenic patients. The results validate the proposed contribution of Furin downregulation in schizophrenia and suggest that defective footshock habituation is a Drosophila protophenotype of the human disorder.SIGNIFICANCE STATEMENT Genome-wide association studies have revealed a number of loci linked to schizophrenia, but most have not been verified experimentally in a relevant behavioral task. Habituation deficits constitute a schizophrenia endophenotype. Drosophila with attenuated expression of the schizophrenia-linked highly conserved Furin gene present delayed habituation reversible with acute exposure to antipsychotics. This strongly suggests that footshock habituation defects constitute a schizophrenia protophenotype in Drosophila Furthermore, determination of the neurons whose regulated activity is required for footshock habituation provides a facile metazoan system to expediently validate putative schizophrenia genes and variants in a well understood simple brain.