Loss of SHROOM3 affects neuroepithelial cell shape through regulating cytoskeleton proteins in cynomolgus monkey organoids.

Neural tube defects (NTDs) are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure. Although folate supplementation has been shown to mitigate the incidence of NTDs, some cases, often attributable to genetic factors, remain unpreventable. The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation; at present, however, the underlying mechanism remains unclear. Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate. To determine the role of SHROOM3 in early developmental morphogenesis, we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase. Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei. These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins, namely fibrous actin (F-actin), myosin II, and phospho-myosin light chain (PMLC), to the apical side of the neuroepithelial cells. Notably, these defects were not rescued by folate supplementation. RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis. In summary, we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation.

Breviscapine, a traditional Chinese medicine, alleviates myocardial ischaemia reperfusion injury in diabetic rats.

OBJECTIVE: The aim of this study was to explore the effects of breviscapine on the expressions of intercellular adhesion molecule-I (ICAM-I), ATPase activities and oxidative stress in ischaemia-reperfused (I/R) myocardium of diabetic rats. METHODS: Sprague Dawley rats were randomly divided into two groups (a diabetic group and a non-diabetic group), and each group divided into two subgroups including a control group and a breviscapine group. Reperfusion surgery was carried out in all rats.The contents of malonaldehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-P(x)) in serum and myocardial tissues were measured. The activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase in myocardial mitochondria were measured. The ICAM-I protein expressions in myocardium were determined with the immunohistochemical method. RESULTS: The activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase were significantly increased in diabetic rats in the breviscapine group compared with the control group. Compared with the non-diabetic control group, the contents of MDA in serum and myocardium were significantly increased in the diabetic control group. Breviscapine led to a reduction of the contents of MDA in the diabetic and non-diabetic group. Compared with the non-diabetic control group, the activities of SOD and GSH-P(x) in the myocardium were significantly decreased in the diabetic control group.The activities of SOD and GSH-P(x) in serum and myocardium were increased in the diabetic and non-diabetic group after breviscapine treatment. Compared with the non-diabetic control group, the ICAM- I protein expressions were increased significantly in the diabetic control group. Breviscapine decreased the ICAM-I protein expression in the diabetic and the non-diabetic group. CONCLUSION: Breviscapine may have protective effects on myocardial ischaemia reperfusion injury of diabetic rats by scavenging oxygen free radicals, decreasing the expressions of ICAM-I protein in myocardium and increasing the activities of Na(+)-K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase in myocardial mitochondria.