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The rapidly increasing prevalence of obesity and overweight, especially in children and adolescents, has become a serious societal issue. Although various genetic and environmental risk factors for pediatric obesity and overweight have been identified, the problem has not been solved. In this study, we examined whether environmental nanoplastic (NP) pollutants can act as environmental obesogens using mouse models exposed to NPs derived from polystyrene and polypropylene, which are abundant in the environment. We found abnormal weight gain in the progeny until 6 weeks of age following the oral administration of NPs to the mother during gestation and lactation. Through a series of experiments involving multi-omic analyses, we have demonstrated that NP-induced weight gain is caused by alterations in the lipid composition (lysophosphatidylcholine/phosphatidylcholine ratio) of maternal breast milk and he gut microbiota distribution of the progeny. These data indicate that environmental NPs can act as obesogens in childhood.

Abstract Intracellular C‐terminal cleavage of the amyloid precursor protein (APP) is elevated in the brains of Alzheimer's disease (AD) patients and produces a peptide labeled APP‐C31 that is suspected to be involved in the pathology of AD. But details about the role of APP‐C31 in the development of the disease are not known. Here, this work reports that APP‐C31 directly interacts with the N‐terminal and self‐recognition regions of amyloid‐β40 (Aβ40) to form transient adducts, which facilitates the aggregation of both metal‐free and metal‐bound Aβ40 peptides and aggravates their toxicity. Specifically, APP‐C31 increases the perinuclear and intranuclear generation of large Aβ40 deposits and, consequently, damages the nucleus leading to apoptosis. The Aβ40‐induced degeneration of neurites and inflammation are also intensified by APP‐C31 in human neurons and murine brains. This study demonstrates a new function of APP‐C31 as an intracellular promoter of Aβ40 amyloidogenesis in both metal‐free and metal‐present environments, and may offer an interesting alternative target for developing treatments for AD that have not been considered thus far.

Abstract Background Spastin significantly influences microtubule regulation in neurons and is implicated in the pathogenesis of hereditary spastic paraplegia (HSP). However, post-translational regulation of the spastin protein remains nebulous. The association between E3 ubiquitin ligase and spastin provides a potential therapeutic strategy. Results As evidenced by protein chip analysis, FBXL17 inversely correlated with SPAST-M1 at the protein level in vitro and, also in vivo during embryonic developmental stage. SPAST-M1 protein interacted with FBXL17 specifically via the BTB domain at the N-terminus of SPAST-M1. The SCFFBXL17 E3 ubiquitin ligase complex degraded SPAST-M1 protein in the nuclear fraction in a proteasome-dependent manner. SPAST phosphorylation occurred only in the cytoplasmic fraction by CK2 and was involved in poly-ubiquitination. Inhibition of SCFFBXL17 E3 ubiquitin ligase by small chemical and FBXL17 shRNA decreased proteasome-dependent degradation of SPAST-M1 and induced axonal extension. The SPAST Y52C mutant, harboring abnormality in BTB domain could not interact with FBXL17, thereby escaping protein regulation by the SCFFBXL17 E3 ubiquitin ligase complex, resulting in loss of functionality with aberrant quantity. Although this mutant showed shortening of axonal outgrowth, low rate proliferation, and poor differentiation capacity in a 3D model, this phenotype was rescued by inhibiting SCFFBXL17 E3 ubiquitin ligase. Conclusions We discovered that a novel pathway, FBXL17-SPAST was involved in pathogenicity of HSP by the loss of function and the quantitative regulation. This result suggested that targeting FBXL17 could provide new insight into HSP therapeutics.

Abstract The neural circuits of the infant brain are rapidly established near 6 months of age, but neurodevelopmental disorders can be diagnosed only at the age of 2–3 years using existing diagnostic methods. Early diagnosis is very important to alleviate life-long disability in patients through appropriate early intervention, and it is imperative to develop new diagnostic methods for early detection of neurodevelopmental disorders. We examined the serum level of secretogranin II (SCG2) in pediatric patients to evaluate its potential role as a biomarker for neurodevelopmental disorders. A plasmonic immunosensor performing an enzyme-linked immunosorbent assay (ELISA) on a gold nanodot array was developed to detect SCG2 in small volumes of serum. This nanoplasmonic immunosensor combined with tyramide signal amplification was highly sensitive to detect SCG2 in only 5 μL serum samples. The analysis using the nanoplasmonic immunosensor revealed higher serum SCG2 levels in pediatric patients with developmental delay than in the control group. Overexpression or knockdown of SCG2 in hippocampal neurons significantly attenuated dendritic arborization and synaptic formation. These results suggest that dysregulated SCG2 expression impairs neural development. In conclusion, we developed a highly sensitive nanoplasmonic immunosensor to detect serum SCG2, a candidate biomarker for the early diagnosis of neurodevelopmental disorders.

Metabolic syndrome (MetS) is a group of risk factors that causes cardiovascular and diabetic morbidity and mortality, which is diagnosed by central obesity, dyslipidemia, hyperglycemia, and hypertension. Increasing epidemiological data and experimental results indicate that the presence of MetS increases the incidence of common malignancies and related mortality. Epidemiological studies have previously reported an association of endometrial cancer occurrence with MetS. Aromatization of androstenedione to estrogen, insulin resistance, and diabetes can cause increased levels of free estrogen, and the detrimental effect of elevated estrogen as a carcinogen is well studied in endometrial cancer. Medications used to manage MetS such as metformin and statins are suggested to reduce endometrial cancer risk and improve survival. Some large population-based epidemiological studies have suggested that the MetS is related to an increased risk of cervical carcinoma. MetS may contribute to viral-host interactions, which lead to persistent human papilloma virus (HPV) infection, although limited epidemiological data are available. Specific effects of obesity and diabetes on the occurrence of ovarian cancer have been suggested. However, the direct correlation between MetS and ovarian cancer is still lacking. Previous retrospective studies reported that the use of metformin, statins, and beta-blockers could be associated with cancer prevention or better prognosis. Proper diagnosis and management of the MetS should be a part of the strategies undertaken to prevent and treat gynecologic cancer. So far, only limited data is available on this subject, and further clinical and fundamental research is required to further clarify the effect of these therapies on gynecologic cancer treatment.

Schwann cells play a crucial role in successful nerve repair and regeneration by supporting both axonal growth and myelination. However, the sources of human Schwann cells are limited both for studies of Schwann cell development and biology and for the development of treatments for Schwann cell-associated diseases. Here, we provide a rapid and scalable method to produce self-renewing Schwann cell precursors (SCPs) from human pluripotent stem cells (hPSCs), using combined sequential treatment with inhibitors of the TGF-β and GSK-3 signaling pathways, and with neuregulin-1 for 18 days under chemically defined conditions. Within 1 week, hPSC-derived SCPs could be differentiated into immature Schwann cells that were functionally confirmed by their secretion of neurotrophic factors and their myelination capacity in vitro and in vivo. We propose that hPSC-derived SCPs are a promising, unlimited source of functional Schwann cells for treating demyelination disorders and injuries to the peripheral nervous system.

The availability of adult malignant glioma stem cells (GSCs) has provided unprecedented opportunities to identify the mechanisms underlying treatment resistance. Unfortunately, there is a lack of comparable reagents for the study of pediatric low-grade glioma (LGG). Leveraging a neurofibromatosis 1 (Nf1) genetically engineered mouse LGG model, we report the isolation of CD133+ multi-potent low-grade glioma stem cells (LG-GSCs), which generate glioma-like lesions histologically similar to the parent tumor following injection into immunocompetent hosts. In addition, we demonstrate that these LG-GSCs harbor selective resistance to currently employed conventional and biologically targeted anti-cancer agents, which reflect the acquisition of new targetable signaling pathway abnormalities. Using transcriptomic analysis to identify additional molecular properties, we discovered that mouse and human LG-GSCs harbor high levels of Abcg1 expression critical for protecting against ER-stress-induced mouse LG-GSC apoptosis. Collectively, these findings establish that LGG cancer stem cells have unique molecular and functional properties relevant to brain cancer treatment.

BackgroundMitochondrial trans-2-enoyl-CoA reductase (MECR) is involved in mitochondrial synthesis of fatty acids and is highly expressed in mitochondria. MECR is also known as nuclear receptor binding factor-1, which was originally reported with yeast two-hybrid screening as a binding protein of the nuclear hormone receptor peroxisome proliferator-activated receptor α (PPARα). However, MECR and PPARα are localized at different compartment, mitochondria, and the nucleus, respectively. Therefore, the presence of a cytosolic or nuclear isoform of MECR is necessary for functional interaction between MECR and PPARα.MethodsTo identify the expression pattern of MECR and the cytosolic form of MECR (cMECR), we performed reverse transcription polymerase chain reaction (RT-PCR) with various tissue samples from Sprague-Dawley rats. To confirm the interaction between cMECR and PPARα, we performed several binding assays such as yeast two-hybrid, coimmunoprecipitation, and bimolecular fluorescence complementation. To observe subcellular localization of these proteins, immunocytochemistry was performed. A luciferase assay was used to measure PPARα activity.ResultsWe provide evidence of an alternatively spliced variant of the rat MECR gene that yields cMECR. The cMECR lacks the N-terminal 76 amino acids of MECR and shows uniform distribution in the cytoplasm and nucleus of HeLa cells. cMECR directly bound PPARα in the nucleus and increased PPARα-dependent luciferase activity in HeLa cells.ConclusionWe found the cytosolic form of MECR (cMECR) was expressed in the cytosolic and/or nuclear region, directly binds with PPARα, and enhances PPARα activity.