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The objective of this study was to investigate the effects and molecular mechanisms of tetrahedral framework nucleic acids‐microRNA22 (tFNAs‐miR22) on inhibiting pathological retinal neovascularization (RNV) and restoring physiological retinal vessels. A novel DNA nanocomplex (tFNAs‐miR22) was synthesised by modifying microRNA‐22 (miR22) through attachment onto tetrahedral frame nucleic acids (tFNAs), which possess diverse biological functions. Cell proliferation, wound healing, and tube formation were employed for in vitro assays to investigate the angiogenic function of cells. Oxygen‐induced retinopathy (OIR) model was utilised to examine the effects of reducing pathological neovascularization (RNV) and inhibiting vascular occlusion in vivo. In vitro, tFNAs‐miR22 demonstrated the ability to penetrate endothelial cells and effectively suppress cell proliferation, tube formation, and migration in a hypoxic environment. In vivo, tFNAs‐miR22 exhibited promising results in reducing RNV and promoting the restoration of normal retinal blood vessels in OIR model through modulation of the Wnt pathway. This study provided a theoretical basis for the further understanding of RNV, and highlighted the innovative and potential of tFNAs‐miR22 as a therapeutic option for ischemic retinal diseases. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effect and the molecular mechanism of tetrahedral framework nucleic acids (tFNAs), a novel self‐assembled nanomaterial with excellent biocompatibility and superior endocytosis ability, in inhibition of pathological retinal neovascularization (RNV) and more importantly, in amelioration of vaso‐obliteration (VO) in ischaemic retinopathy. tFNAs were synthesized from four single‐stranded DNAs (ssDNAs). Cell proliferation, wound healing and tube formation assays were performed to explore cellular angiogenic functions in vitro. The effects of tFNAs on reducing angiogenesis and inhibiting VO were explored by oxygen‐induced retinopathy (OIR) model in vivo. In vitro, tFNAs were capable to enter endothelial cells (ECs), inhibit cell proliferation, tube formation and migration under hypoxic conditions. In vivo, tFNAs successfully reduce RNV and inhibit VO in OIR model via the PI3K/AKT/mTOR/S6K pathway, while vascular endothelial growth factor fusion protein, Aflibercept, could reduce RNV but not inhibit VO. This study provides a theoretical basis for the further understanding of RNV and suggests that tFNAs might be a novel promising candidate for the treatment of blind‐causing RNV. [ABSTRACT FROM AUTHOR]

Age‐related macular degeneration (AMD) and diabetic retinopathy (DR) are the world's leading causes of blindness. The retinal pigment epithelium (RPE) and vascular endothelial cell exposed to oxidative stress is the major cause of AMD and DR. DJ‐1, an important endogenous antioxidant, its overexpression is considered as a promising antioxidant treatment for AMD and DR. Here, we modified the tetrahedral frame nucleic acids (tFNAs) with DJ‐1 saRNAs as a delivery system, and synthesized a novel nanocomplex (tFNAs‐DJ‐1 saRNAs). In vitro studies show that tFNAs‐DJ‐1 saRNAs can efficiently transfer DJ‐1 saRNAs to human umbilical vein endothelial cells (HUVECs) and ARPE‐19s, and significantly increased their cellular DJ‐1 level. Reactive oxygen species expression in H2O2‐treated HUVECs and ARPE‐19s were decreased, cell viability was enhanced and cell apoptosis were inhibited when tFNAs‐DJ‐1 saRNAs were delivered. Moreover, tFNAs‐DJ‐1 saRNAs preserved mitochondrial structure and function under oxidative stress conditions. In the aspect of molecular mechanism, tFNAs‐DJ‐1 saRNAs activated Erk and Nrf2 pathway, which might contribute to its protective effects against oxidative stress damage. To conclude, this study shows the successfully establishment of a simple but effective delivery system of DJ‐1 saRNAs associated with antioxidant effects in AMD and DR, which may be a promising agent for future treatment in oxidative stress‐related retinal disorders. [ABSTRACT FROM AUTHOR]

Background: Inflammatory bowel disease (IBD) is a non‐specific chronic inflammatory disease of the intestine. In addition to genetic susceptibility, environmental factors and dysregulated host immunity, the gut microbiota is implicated in the pathogenesis of Crohn's disease (CD) or ulcerative colitis (UC), the two primary types of IBD. The P2X4 receptor has been demonstrated to have a crucial role in preventing infection, inflammation, and organ damage. However, it remains unclear whether the P2X4 receptor affects IBD and the underlying mechanisms. Methods: Colitis was induced in mice administrated with dextran sodium sulphate (DSS). 16S rDNA sequencing was used to analyze the gut microbiota in knockout and wild‐type mice. Clinical and histopathological parameters were monitored throughout the disease progression. Results: Gene Expression Omnibus analysis showed the downregulation of P2RX4 (P2rx4) expression in colonic tissues from patients or mice with IBD. However, its expression at the protein levels was upregulated on day 4 or 6 and then downregulated on day 7 in C57BL/6 mice treated with DSS. Gene ablation of P2rx4 aggravated DSS‐induced colitis accompanying gut microbiota dysbiosis in mice. Moreover, P2X4 receptor‐positive modulator ivermectin alleviated colitis and corrected dysregulated microbiota in wild‐type C57BL/6 mice. Further antibiotic‐treated gut microbiota depletion, cohousing experiment, and fecal microbiota transplantation proved that gut microbiota dysbiosis was associated with the aggravation of colitis in the mouse model initiated by P2rx4. Conclusions: Our findings elaborate on an unrevealed etiopathophysiological mechanism by which microbiota dysbiosis induced by the P2X4 receptor influences the development of colitis, indicating that the P2X4 receptor represents a promising target for treating patients with CD and UC. [ABSTRACT FROM AUTHOR]

Background: To investigate the relationships among phenotypes, genotypes, and funotypes of SCN2A‐related developmental epileptic encephalopathy (DEE). Methods: We enrolled five DEE patients with five de novo variants of the SCN2A. Functional analysis and pharmacological features of Nav1.2 channel protein expressed in HEK293T cells were characterized by whole‐cell patch‐clamp recording. Results: The phenotypes of c.4712T>C(p. I1571T), c.2995G>A(p.E999K), and c.4015A>G(p. N1339D) variants showed similar characteristics, including early seizure onset with severe to profound intellectual disability. Electrophysiological recordings revealed a hyperpolarizing shift in the voltage dependence of the activation curve and smaller recovery time constants of fast‐inactivation than in wild type, indicating a prominent gain of function (GOF). Moreover, pharmacological electrophysiology showed that phenytoin inhibited over a 70% peak current and was more effective than oxcarbazepine and carbamazepine. In contrast, c.4972C>T (p.P1658S) and c.5317G>A (p.A1773T) led to loss of function (LOF) changes, showing reduced current density and enhanced fast inactivation. Both showed seizure onset after 3 months of age with moderate development delay. Interestingly, we discovered that choreoathetosis was a specific phenotype feature. Conclusion: These findings provided the insights into the phenotype–genotype–funotype relationships of SCN2A‐related DEE. The preliminary evaluation using the distinct hints of GOF and LOF helped plan the treatment, and the next precise step should be electrophysiological study. [ABSTRACT FROM AUTHOR]

Epilepsy is a common and genetically heterogeneous disorder among children. Advances in next‐generation sequencing have revealed that numerous epilepsy genes, helped us improve the understanding of mechanisms underlying epileptogenesis, and guided the development of treatments. We identified 39 candidate variants in 21 genes, including 37 that were pathogenic or likely pathogenic variants according to the American College of Medical Genetics and Genomics scoring system and two variants of uncertain significance that were considered causative after they were associated with clinical characteristics. Thirty were de novo variants (76.9%), and 20 variants had not previously been reported (51.3%). We obtained a diagnosis in 39 of the 141 probands (27.7%). The most frequently mutated gene was SCN1A; KCNQ2, KCNT1, PCDH19, STXBP1, SCN2A, TSC2, and PRRT2 were mutated in more than one individual; ANKRD11, CDKL5, DCX, DEPDC5, GABRB3, GRIN2A, IQSEC2, KCNA2, KCNB1, KCNJ6, TSC1, SCN9A, and SCN1B were mutated in a single individual. In addition, we detected a nonsense variant in a candidate gene KCND1 and considered it as a new candidate epilepsy gene, which needed further functional study. Consequently, large number of unreported variants were detected, diverse phenotypes were associated with known epilepsy genes. Changes in clinical management beyond genetic counseling were suggested. [ABSTRACT FROM AUTHOR]