8 research outputs found
Cognitive Enhancing and Neuroprotective Effect of the Embryo of the Nelumbo nucifera
The aim of the present study was to evaluate the effect of ENS on cognitive impairment induced by scopolamine and its potential neuroprotective effect against glutamate-induced cytotoxicity in HT22 cell and to investigate the underlying mechanisms. ENS (3, 10, 30, and 100โmg/kg), scopolamine (1โmg/kg), and donepezil (1โmg/kg) were administered to mice during a test period. Scopolamine impaired memory and learning in a water maze test and a passive avoidance test. The neuroprotective effect of ENS (10 and 100โฮผg/mL) was investigated on glutamate-induced cell death in HT22 cells by MTT assay. We investigated acetylcholinesterase inhibition in hippocampus and antioxidant activity, ROS levels, and Ca2+ influx in HT22 cells to elucidate the potential mechanisms of ENS. We found that ENS significantly ameliorated scopolamine-induced memory impairment and inhibited AChE activity in hippocampus. In vitro, ENS showed potent neuroprotective effects against glutamate-induced neurotoxicity in the HT22 cell. In addition, ENS induced a decrease in ROS production and intercellular Ca2+ accumulation and showed DPPH radical and H2O2 scavenging activity. In conclusion, ENS showed both a memory improving effect and a neuroprotective effect. Our results indicate that ENS may be of use in the treatment and prevention of neurodegenerative disorders
Idiopathic retroperitoneal fibrosis associated with Hashimoto's thyroiditis in a patient with a single functioning kidney
AbstractRetroperitoneal fibrosis (RPF) is a rare disease characterized by the presence of fibroinflammatory tissue around the abdominal aorta and ureteral entrapment in most cases. Idiopathic RPF is frequently reported in association with autoimmune diseases; however, there have been few reports of idiopathic RPF associated with Hashimoto's thyroiditis. Here, we report a case of idiopathic RPF with Hashimoto's thyroiditis in a patient with a single functioning kidney, which was successfully treated by corticosteroid therapy and transient intraureteral stent insertion with a double-J catheter
Beclin 1 functions as a negative modulator of MLKL oligomerisation by integrating into the necrosome complex
Necroptosis is a form of regulated cell death caused by formation of the necrosome complex. However, the factors modulating this process and the systemic pathophysiological effects of necroptosis are yet to be understood. Here, we identified that Beclin 1 functions as an anti-necroptosis factor by being recruited into the necrosome complex upon treatment with TNF alpha, Smac mimetic, and pan-caspase inhibitor and by repressing MLKL oligomerisation, thus preventing the disruption of the plasma membrane. Cells ablated or knocked-out for Beclin 1 become sensitised to necroptosis in an autophagy-independent manner without affecting the necrosome formation itself. Interestingly, the recruitment of Beclin 1 into the necrosome complex is dependent on the activation and phosphorylation of MLKL. Biochemically, the coiled-coil domain (CCD) of Beclin 1 binds to the CCD of MLKL, which restrains the oligomerisation of phosphorylated MLKL. Finally, Beclin 1 depletion was found to promote necroptosis in leukaemia cells and enhance regression of xenografted-tumour upon treatment with Smac mimetics and caspase inhibitors. These results suggest that Beclin 1 functions as a negative regulator in the execution of necroptosis by suppressing MLKL oligomerisation
Conservation and divergence of FCA function between Arabidopsis and rice.
Although several genes have been identified in rice which are functionally equivalent to the flowering time genes in Arabidopsis, primarily genes involved in the photoperiod pathway, little data is available regarding the genes that function in the autonomous pathway in rice. In order to acquire further insight into the control of heading dates in rice, we isolated and conducted an expression analysis on OsFCA, which exhibited 38% sequence homology with Arabidopsis FCA. The N-terminal region of the OsFCA protein appears to be unusually rich in glycine-residues, unlike the N-terminal region found in FCA. However, the genetic structure of OsFCA is, in general, similar to that of FCA. RT-PCR and in silico analyses also showed that alternative splicing and polyadenylation at intron3 were conserved in the genetic expression of OsFCA. We were able to detect alpha, beta, and gamma transcripts, but not the delta transcript, of the OsFCA gene. The beta and gamma transcripts of the OsFCA gene were detected via Northern analysis in the leaves, roots, and flowers of the plant. Flowers in younger stages exhibited higher transcript levels. These data suggest that intron3 may constitute a primary control point in the OsFCA pre-mRNA processing of rice. The overexpression of OsFCA cDNA, driven by the 35S promoter, was shown to partially rescue the late flowering phenotype of the fca mutant, suggesting that the functions of the OsFCA and the FCA are partially overlapped, despite the lack of an apparent FLC homologue in the rice genome. The constitutive expression of OsFCA resulted in no downregulation of FLC, but did result in the weak upregulation of SOC1 in the transgenic Arabidopsis. OsFCA overexpression did not result in a reduction of the gamma transcript levels of FCA in the transgenic Arabidopsis either, thereby suggesting that OsFCA had no effects on the autoregulation of Arabidopsis FCA. All of these results imply conservation and divergence in the functions of FCA between rice and Arabidopsis
NFAT1 regulates systemic autoimmunity through the modulation of a dendritic cell property
The transcription factor NFAT1 plays a pivotal role in the homeostasis of T lymphocytes. However, its functional importance in non-CD4+ T cells, especially in systemic immune disorders, is largely unknown. In this study, we report that NFAT1 regulates dendritic cell (DC) tolerance and suppresses systemic autoimmunity using the experimental autoimmune myasthenia gravis (EAMG) as a model. Myasthenia gravis and EAMG are T cell-dependent, Ab-mediated autoimmune disorders in which the acetylcholine receptor is the major autoantigen. NFAT1-knockout mice showed higher susceptibility to EAMG development with enhanced Th1/Th17 cell responses. NFAT1 deficiency led to a phenotypic alteration of DCs that show hyperactivation of NF-kB-mediated signaling pathways and enhanced binding of NF-kB (p50) to the promoters of IL-6 and IL-12. As a result, NFAT1-knockout DCs produced much higher levels of proinflammatory cytokines such as IL-1b, IL-6, IL-12, and TNF-a, which preferentially induce Th1/Th17 cell differentiation. Our data suggest that NFAT1 may limit the hyperactivation of the NF-kB-mediated proinflammatory response in DCs and suppress autoimmunity by serving as a key regulator of DC tolerance. Copyright ยฉ 2017 by The American Association of Immunologists, Inc.1211sciescopu
Loss of the E3 ubiquitin ligase MKRN1 represses diet-induced metabolic syndrome through AMPK activation
AMP-activated protein kinase (AMPK) plays a key role in controlling energy metabolism in
response to physiological and nutritional status. Although AMPK activation has been proposed
as a promising molecular target for treating obesity and its related comorbidities, the
use of pharmacological AMPK activators has been met with contradictory therapeutic
challenges. Here we show a regulatory mechanism for AMPK through its ubiquitination and
degradation by the E3 ubiquitin ligase makorin ring finger protein 1 (MKRN1). MKRN1
depletion promotes glucose consumption and suppresses lipid accumulation due to AMPK
stabilisation and activation. Accordingly, MKRN1-null mice show chronic AMPK activation in
both liver and adipose tissue, resulting in significant suppression of diet-induced metabolic
syndrome. We demonstrate also its therapeutic effect by administering shRNA targeting
MKRN1 into obese mice that reverses non-alcoholic fatty liver disease. We suggest that
ubiquitin-dependent AMPK degradation represents a target therapeutic strategy for metabolic
disorders.ยฉ The Author(s) 201