Association of the retinol to all-trans retinoic acid pathway with autism spectrum disorder.

BACKGROUND: Autism spectrum disorder (ASD) is a complex group of neurodevelopmental disorders. Research has highlighted a close association between the retinoic acid (RA) signaling pathway and ASD. This study investigates alterations in the vitamin A (VA, retinol) to RA metabolic pathway in children with ASD and speculates on the underlying reasons for these changes. We propose a subtype characterized by downregulated RA signaling in ASD, laying the groundwork for precise diagnosis and treatment research. METHODS: We included 489 children with ASD and 280 typically developing (TD) children. Those with ASD underwent evaluations of core symptoms and neuro-developmental levels, which were conducted by professional developmental behavior physicians using assessment scales. Serum VA and all-trans RA (atRA) levels were determined by high-performance liquid chromatography and ultra-high-performance liquid chromatography-tandem mass spectrometry. The expression levels and concentrations of enzyme molecules such as retinol dehydrogenase 10 were assessed using quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Children with ASD exhibited reduced serum atRA, accompanied by a downregulation of atRA synthesis enzymes. The reduction in serum atRA levels was linked not only to VA levels but also to the aberrant expression of metabolic enzymes responsible for atRA. Furthermore, the serum atRA levels in children with ASD were more strongly correlated with core symptoms and neurodevelopmental levels than VA levels. CONCLUSION: Children with ASD exhibited a dual regulation of reduced serum atRA levels, influenced by both VA levels and abnormal expression of atRA metabolic enzymes.

Epigallocatechin-3-gallate restores mitochondrial homeostasis impairment by inhibiting HDAC1-mediated NRF1 histone deacetylation in cardiac hypertrophy.

Decompensated cardiac hypertrophy is accompanied by impaired mitochondrial homeostasis, whether histone acetylation is involved in this process is yet to be determined. The role of HDAC1-mediated NRF1 histone deacetylation was investigated in transverse aortic constriction (TAC)-induced hypertrophy in rats and phenylephrine (PE)-induced hypertrophic cardiomyocytes. Administration of epigallocatechin-3-gallate (EGCG), an inhibitor of HDAC1, restored cardiac function, decreased heart/body weight and fibrosis, increased the ratio of mtDNA/nDNA and the percentage of LysoTracker+ CMs in TAC, compared with TAC without receiving EGCG. In PE-treated hypertrophic H9C2 cells, EGCG attenuated cell hypertrophy and increased LC3B II+MitoTracker+ puncta, as well as the ratio of mtDNA/nDNA. Interestingly, NRF1 but not PGC-1α expression was decreased in TAC- or PE-induced hypertrophic hearts or cells, respectively, while EGCG upregulated both NRF1 and PGC-1α in vitro. EGCG treatment also increased the interaction between PGC-1α and NRF1. In addition to inhibiting HDAC1 expression, EGCG decreased the binding of HDAC1 and increased the binding of acH3K9 or acH3K14 in the promotor regions of PGC-1α and NRF1. In neonatal rat cardiomyocytes, restored NRF1, TFAM and FUNDC1 were abolished by the overexpression of HDAC1. Collectively, data suggest that NRF1 reduction was averted by EGCG via inhibiting HDAC1-mediated histone deacetylation. Acetylation of NRF1 histone may play a key role in maintaining mitochondrial homeostasis associated with cardiac hypertrophy.

New insight into the mechanism of Pt(0)-catalyzed hydrosilylation reaction of (CH3)3SiH with CH2CHSi(CH3)3.

The non-catalytic hydrosilylation reaction has much high activation energy due to large differences in the energy of HOMO-LUMO pairing and restriction of the orbital symmetry overlap. For Pt(0)-catalytic hydrosilylation, the electronic structure of Me3SiH has been modified by the oxidative addition of Pt(0). It not only narrows down the energy differences between the bonding orbitals but also improves the orbital overlap symmetry, leading to the effective decrease of the activation energy. The trouble for the Pt(0)-catalytic hydrosilylation is the formation of the majority of the Pt-containing intermediates. Because they are fallen into the deep potential-energy, the reductive eliminations are energetically prohibitive, which is the essence of Pt-contamination. The reductive elimination can be achieved with the ligand exchange method, and the energy barrier can be tuned by suitable ligands.

Epigallocatechin-3-gallate exerts cardioprotective effects related to energy metabolism in pressure overload-induced cardiac dysfunction.

BACKGROUND: To investigate the mechanisms of potential cardioprotective effects of epigallocatechin-3-gallate (EGCG) in pressure overload-induced cardiac dysfunction. METHODS: A chronic heart failure model was established using abdominal aortic constriction (AAC) surgery, rats were divided into sham, AAC, and AAC + EGCG groups. Echocardiography and tissue section staining were performed to evaluate cardiac function and pathology, respectively. Gene expression level were detected with quantitative real-time polymerase chain reactions. Label-free quantitative proteomics was used to investigate the whole proteomes of heart, and the differentially expressed proteins were analyzed using bioinformatics methods. Western blot was performed to validate the levels and the reliability of the differential proteins. RESULTS: Compared with the AAC group, systolic dysfunction was improved in AAC + EGCG group after EGCG treatment. EGCG inhibited myocardial fibrosis and cardiac hypertrophy after AAC, along with reducing atrial natriuretic protein, B-type natriuretic peptide, collagen types 1 and 3 alpha 1, and transforming growth factor ß-1. Quantitative proteomics identified a total of 162 differentially expressed proteins, among them, 18 were closely related to cardiovascular disorders. Bioinformatics analyses showed that EGCG played a therapeutic role mainly by changing energy metabolism processes, such as oxidative phosphorylation and lipid metabolism. Furthermore, NADH: ubiquinone oxidoreductase subunit S4, an important component of the mitochondrial respiratory chain, was increased after AAC and then reversed by EGCG, which was consistent with the proteomics results. CONCLUSIONS: EGCG may correct cardiac systolic dysfunction and prevent cardiac remodeling after heart failure via enhancing the energy metabolism, which provides us with new insights into cardioprotective effects of EGCG related to the energy metabolisms in pressure overload-induced cardiac dysfunction.

Treg/Th17 Ratio Regulation May Play an Important Role in Epigallocatechin-3-Gallate-Mediated Attenuation of Increased Afterload-Induced Cardiac Hypertrophy.

ABSTRACT: The aim of this study was to investigate whether Treg/Th17 ratio regulation plays an important role in epigallocatechin-3-gallate (EGCG) in attenuating increased afterload-induced cardiac hypertrophy. Three-month-old male C57BL/6 mice were divided into sham + vehicle, abdominal aortic constriction (AAC) + vehicle, and AAC + EGCG groups. Intraperitoneal EGCG (50 mg/kg/d) administration was conducted. Cardiac structure and function were examined by ultrasonography. Pathology was examined by hematoxylin and eosin staining, wheat germ agglutinin staining, and Masson's trichome staining. T-lymphocyte subtypes were analyzed using immunofluorescence and flow cytometry assays. Ultrasonography showed that the ventricular wall in the AAC + vehicle group was thicker than that in the sham + vehicle group (P < 0.05). Hematoxylin and eosin staining revealed cardiomyocyte hypertrophy accompanied by a small amount of inflammatory cell infiltration in the AAC + vehicle group. The results of wheat germ agglutinin staining demonstrated the presence of hypertrophic cardiomyocytes in the AAC + vehicle group (P < 0.01). Masson's trichome staining showed cardiac fibrosis in the AAC + vehicle group, and the immunofluorescence assay revealed infiltration of CD4+ cells in both AAC + vehicle and AAC + EGCG groups. Splenic flow cytometry showed a significant increase in the proportion of Treg cells in the AAC + EGCG group (P < 0.05). The proportion of Th17 cells in the AAC + vehicle group was significantly higher than that in the sham + vehicle group (P < 0.05). In conclusion, changes in the Treg/Th17 ratio are associated with the occurrence of myocardial hypertrophy caused by increased afterload. Moreover, regulation of the Treg/Th17 ratio by EGCG may play an important role in the attenuation of myocardial hypertrophy.