71 research outputs found
Alteration of somatosensory response in adulthood by early life stress
Early-life stress is well known as a critical risk factor for mental and cognitive disorders in adulthood. Such disorders are accompanied by altered neuro- (synapto-) genesis and gene expression. Because psychosomatic disorders induced by early-life stress (e.g., physical and/or sexual abuse, and neglect) have become a socio-economic problem, it is very important to clarify the mechanisms underlying these changes. However, despite of intensive clinical and animal studies, such mechanisms have not yet been clarified. Although the disturbance of glucocorticoid and glutamate homeostasis by stress has been well documented, it has not yet been clarified whether such disturbance by early-life stress persists for life. Furthermore, since previous studies have focused on the detection of changes in specific brain regions, such as the hippocampus and prefrontal cortex, it has not been clarified whether early-life stress induced changes in the sensory/motor system. Thus, in this review, we introduce recent studies on functional/structural changes in the somatosensory cortex induced by early-life stress. We believe that this review provides new insights into the functional alteration of the somatosensory system induced by early-life stress. Such information may have clinical relevance in terms of providing effective therapeutic interventions to early-life-stressed individuals
Studi Meta-Analisis: Hubungan antara Defisiensi Vitamin D dan Penyakit Parkinson
Beberapa penelitian telah dilakukan untuk mengevaluasi kadar 25(OH)D pada pasien penyakit Parkinson. Namun, hasil penelitian ini tidak konsisten. Penelitian ini melakukan meta-analisis terhadap kadar 25(OH)D pada pasien dengan penyakit Parkinson. Database PubMed digunakan untuk melakukan pencarian literatur secara sistematis. Meta-analisis dilakukan dengan menggunakan model efek acak untuk menghitung perkiraan efek gabungan. Tujuh belas artikel dimasukkan dalam penelitian ini. Meta-analisis mengungkapkan bahwa pasien dengan penyakit Parkinson memiliki kadar 25(OH)D yang lebih rendah dibandingkan dengan kontrol. Temuan dari artikel prospektif dan retrospektif sebagian besar konsisten. Besarnya respon nocebo dalam uji coba terkontrol acak yang dirancang paralel pada penyakit Parkinson sangat penting dan harus dipertimbangkan dalam interpretasi hasil keamanan dan dalam desain dan interpretasi uji klinis masa depan.
Aberrant Cerebellar Development in Mice Lacking Dual Oxidase Maturation Factors
Background: Thyroid hormone (TH) plays a key role in the developing brain, including the cerebellum. TH deficiency induces organizational changes of the cerebellum, causing cerebellar ataxia. However, the mechanisms causing these abnormalities are poorly understood. Various animal models have been used to study the mechanism. Lacking dual oxidase (DUOX) and its maturation factor (DUOXA) are major inducers of congenital hypothyroidism. Thus, this study examined the organizational changes of the cerebellum using knockout mice of the Duoxa gene (Duoxa?/?). Methods: The morphological, behavioral, and electrophysiological changes were analyzed in wild type (Wt) and Duoxa-deficient (Duoxa?/?) mice from postnatal day (P) 10 to P30. To detect the changes in the expression levels of presynaptic proteins, Western blot analysis was performed. Results: The proliferation and migration of granule cells was delayed after P15 in Duoxa?/? mice. However, these changes disappeared by P25. Although the cerebellar structure of Duoxa?/? mice was not significantly different from that of Wt mice at P25, motor coordination was impaired. It was also found that the amplitude of paired-pulse facilitation at parallel fiber?Purkinje cell synapses decreased in Duoxa?/? mice, particularly at P15. There were no differences between expression levels of presynaptic proteins regulating neurotransmitter release at P25. Conclusions: These results indicate that the anatomical catch-up growth of the cerebellum did not normalize its function because of the disturbance of neuronal circuits by the combined effect of hypothyroidism and functional disruption of the DUOX/DUOXA complex.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140263/1/thy.2015.0034.pd
Thyroid hormone in brain and brain cells
Editorial.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).Peer Reviewe
COUP-TFII in Kidneys, from Embryos to Sick Adults
Chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII) is an orphan nuclear hormone receptor of unknown ligands. This molecule has two interesting features: (1) it is a developmental gene, and (2) it is a potential hormone receptor. Here, we describe the possible roles of COUP-TFII in the organogenesis of the kidneys and protection from adult renal diseases, primarily in mouse models. COUP-TFII is highly expressed in embryos, including primordial kidneys, and is essential for the formation of metanephric mesenchyme and the survival of renal precursor cells. Although the expression levels of COUP-TFII are low and its functions are unknown in healthy adults, it serves as a reno-protectant molecule against acute kidney injury. These are good examples of how developmental genes exhibit novel functions in the etiology of adult diseases. We also discuss the ongoing research on the roles of COUP-TFII in podocyte development and diabetic kidney disease. In addition, the identification of potential ligands suggests that COUP-TFII might be a novel therapeutic target for renal diseases in the future
Suppression of Thyroid Hormone Receptor-Mediated Transcription by Methamidophos
Methamidophos is a cholinesterase inhibitor organophosphate (OP) used
commonly as a pesticide. Its use is currently a global concern due to
widespread occurrence, persistence, bioaccumulation and neurotoxic
potential. We therefore examined the effect of methamidophos on thyroid
hormone receptor (TR)-mediated gene expression using transient
transfection-based reporter gene assay. Our results shows that
methamidophos (10-6 M) suppressed thyroid hormone (TH)-induced
TR-mediated transcription. We further examined the effects of
methamidophos on TR-thyroid hormone response element (TRE) binding
using the liquid chemiluminescent DNA pull-down assay (LCDPA), and
found no dissociation of TR from TRE. Using mammalian two hybrid assay,
we showed that methamidophos did not recruit co-activator (steroid
receptor co-activator 1; SRC-1) to TR in the presence of TH. Also, it
did not recruit co-repressors (nuclear co-repressor; NCoR) to TR in the
absence of TH at all concentrations examined. The effects of
methamidophos on cerebellar Purkinje cell dendritogenesis, granule cell
neurite morphology and synaptic plasticity are currently under
investigation. Taken together, our results show that methamidophos can
potentially disrupt TR–mediated gene expression, suggesting that
methamidophos may interfere with thyroid hormone-mediated activities in
various target organs including the developing brain
DE71 suppresses thyroid hormone-mediated dendritogenesis and neuritogenesis in the developing cerebellum
Polybrominated diphenylethers (PBDEs) are synthesized chemicals
essential to minimize accidents and deaths resulting from
fire-outbreaks. Despite their usefulness, public health concern is on
the increase over their use. PBDE is global in use, persistent in the
environment, and possess the ability to bio-accumulate. Previous
studies have suggested that they may interfere with thyroid hormone
homeostasis, and are neurotoxic. We therefore investigated the effects
of DE71 (a PBDE mixture) on thyroid hormone (TH)-mediated developments
in the cerebellum. Employing primary cerebellar culture from new born
rats, our study revealed that low dose DE71 significantly suppressed
TH-mediated Purkinje cell dendrite arborization. Also, low dose DE71
remarkably impaired neurite extension of granule cells obtained from
reaggregate culture of new born rat cerebella. Taken together, our
study clearly reveals that DE71 can impair TH-mediated neuronal
development in the cerebellum and may therefore interfere with normal
TH-induced brain growth and function
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