ABSTRACT
Tuberous sclerosis complex (TSC) is a genetic disease characterized by seizures, mental deficiency, and abnormalities of the skin, brain, kidney, heart, and lungs. TSC is inherited in an autosomal dominant manner and is caused by variations in either the TSC1 or TSC2 gene. TSC-related epilepsy (TRE) is the most prevalent and challenging clinical feature of TSC, and more than half of the patients have refractory epilepsy. In clinical practice, we found several patients of intractable epilepsy caused by TSC1 truncating mutations. To study the changes of protein expression in the brain, three cases of diseased brain tissue with TSC1 truncating mutation resected in intractable epilepsy operations and three cases of control brain tissue resected in craniocerebral trauma operations were collected to perform protein spectrum detection, and then the data-independent acquisition (DIA) workflow was used to analyze differentially expressed proteins. As a result, there were 55 up- and 55 down-regulated proteins found in the damaged brain tissue with TSC1 mutation compared to the control. Further bioinformatics analysis revealed that the differentially expressed proteins were mainly concentrated in the synaptic membrane between the patients with TSC and the control. Additionally, TSC1 truncating mutations may affect the pathway of amino acid metabolism. Our study provides a new idea to explore the brain damage mechanism caused by TSC1 mutations.
ABSTRACT
Long non-coding RNA MALAT1 was previously revealed to express abnormally in animal and cellular models of stroke, suggesting its indispensable role in stroke. The aims of the present study were to further investigate the functions of MALAT1 and to elucidate the underlying molecular mechanisms. Oxygen glucose deprivation/re-oxygenation (OGD/R) challenge was used in human brain microvascular endothelial cells (HBMECs) to mimic stroke injury in vitro. MALAT1 and miR-205-5p expression levels were evaluated by qRT-PCR. A tube formation assay was employed to verify the angiogenesis of HBMECs. Cell proliferation and apoptosis were evaluated using the ErdU assay and flow cytometry analysis, respectively. The interaction between miR-205-5p and MALAT1 was verified by dual-luciferase reporter assay. MALAT1 and miR-205-5p were both significantly upregulated in the serum of CIS patients and HBMECs under OGD/R, and the tube formation of HBMECs was damaged after OGD/R treatment. Silencing miR-205-5p remarkably promoted HBMEC proliferation and angiogenesis to resist OGD/R injury. Knockdown of MALAT1 markedly inhibited HBMEC proliferation and angiogenesis, and meanwhile promoted apoptosis induced by OGD/R treatment. Most importantly, MALAT1 acted as a competing endogenous RNA (ceRNA) of miR-205-5p via direct bonding with each other in HBMECs under OGD/R damage, indirectly upregulating the downstream targeted gene VEGFA. MALAT1 protected the angiogenesis function of HBMECs under OGD/R conditions by interacting with miR-205-5p/VEGFA pathway.
