Chun-Hui Sun

Epigenetic modification of miR-10a regulates renal damage by targeting CREB1 in type 2 diabetes mellitus.

Emerging evidence has shown that microRNA-mediated gene expression modulation plays a crucial role in the pathogenesis of type 2 diabetes mellitus, but the novel miRNAs involved in type 2 diabetes and its functional regulatory mechanisms still need to be determined. In this study, we assessed the role of miR-10a in extracellular matrix accumulation in the kidney of diabetic mellitus induced by combining administration of chronic high fat diet (HFD) and low dosage of streptozotocin (STZ, 35mg/kg). Here, we found that HFD/STZ administration decreased the level of microRNA (miR-10a) expression in ICR strain mice. Overexpression of miR-10a alleviated the increased ratio of urine albumin-to-creatinine (ACR) ratio of HFD/STZ mice. In contrast, knockdown of miR-10a increased the ratio of kidney ACR in naïve mice. Furthermore, cAMP response element binding protein 1 (CREB1) was validated as a target of miR-10a in vitro and in vivo. CREB1 and its downstream fibronectin (FN, extracellular matrix) were increased in HFD/STZ-treated mice, which was reversed by kidney miR-10a overexpression. The content of CREB1 and FN was increased by miR-10a knockdown in kidney of naïve mice. Furthermore, histone deacetylase 3 (HDAC3) was revealed to be increased in kidney of HFD/STZ mice, accompanied with the augmentation of ACR ratio and FN level. Knockdown of HDAC3 with siRNA significantly caused the increase of miR-10a, resulting in the decrease in CREB1 and FN expression in kidney of HFD/STZ mice. Contrarily, HDAC3 overexpression mediated by lentivirus decreased miR-10a content, and enhanced ACR value, CREB1 and FN formation in naïve mice. Collectively, these results elucidate that HDAC3/miR-10a/CREB1 serves as a new mechanism underlying kidney injury, providing potential therapeutic targets in type 2 diabetes.

Purple sweet potato color inhibits endothelial premature senescence by blocking the NLRP3 inflammasome

Purple sweet potato color (PSPC), flavonoids isolated from purple sweet potato, has been well demonstrated for the pharmacological properties. In the present study, we attempt to explore whether the antisenescence was involved in PSPC-mediated protection against endothelium dysfunction in type 2 diabetes mellitus (T2DM) and, if involved, what are the possible mechanisms. The results showed that atherogenesis and endothelial senescence in the thoracic aorta were promoted in mice with prediabetes; meanwhile, PSPC attenuated the deterioration of vascular vessel and inhibited the endothelial senescence. Diabetes mellitus is a documented high-risk factor for the development of atherosclerosis. Studies show that D-galactose (D-gal) promotes endothelial cell senescence in vitro. In our study, we have determined that PSPC could suppress the D-gal-induced premature senescence and the abnormal endothelial function, discovered in the early stages of atherosclerosis induced by T2DM. We have discovered that the PSPC down-regulates reactive oxygen species (ROS) accumulation and the NLRP3 inflammasome functions. Furthermore, the premature senescence induced by D-gal was inhibited after attenuation of ROS and deactivation of NLRP3 inflammasomes. However, once the NLRP3 inflammasomes are overactivated, PSPC could not restrain cell senescence. These data imply that the beneficial effects of PSPC on diabetes-induced endothelial dysfunction and senescence are mediated through ROS and NLRP3 signaling pathways, suggesting a potential target for the prevention of endothelial senescence-related cardiovascular diseases.

Relationship Between Neonatal Vitamin D at Birth and Risk of Autism Spectrum Disorders: the NBSIB Study

Previous studies suggested that lower vitamin D might be a risk factor for autism spectrum disorders (ASDs). The aim of this study was to estimate the prevalence of ASDs in 3‐year‐old Chinese children and to examine the association between neonatal vitamin D status and risk of ASDs. We conducted a study of live births who had taken part in expanded newborn screening (NBS), with outpatient follow‐up when the children 3‐year old. The children were confirmed for ASDs in outpatient by the Autism Diagnostic Interview‐Revised and Diagnostic and Statistical Manual of Mental Disorders (DSM)‐5 criteria. Intellectual disability (ID) status was defined by the intelligence quotient (IQ < 80) for all the participants. The study design included a 1:4 case to control design. The concentration of 25‐hydroxyvitamin D3 [25(OH)D3] in children with ASD and controls were assessed from neonatal dried blood samples. A total of 310 children were diagnosed as having ASDs; thus, the prevalence was 1.11% (95% CI, 0.99% to 1.23%). The concentration of 25(OH)D3 in 310 ASD and 1240 controls were assessed. The median 25(OH)D3 level was significantly lower in children with ASD as compared to controls (p < 0.0001). Compared with the fourth quartiles, the relative risk (RR) of ASDs was significantly increased for neonates in each of the three lower quartiles of the distribution of 25(OH)D3, and increased risk of ASDs by 260% (RR for lowest quartile: 3.6; 95% CI, 1.8 to 7.2; p < 0.001), 150% (RR for second quartile: 2.5; 95% CI, 1.4 to 3.5; p = 0.024), and 90% (RR for third quartile: 1.9; 95% CI, 1.1 to 3.3; p = 0.08), respectively. Furthermore, the nonlinear nature of the ID‐risk relationship was more prominent when the data were assessed in deciles. This model predicted the lowest relative risk of ID in the 72rd percentile (corresponding to 48.1 nmol/L of 25(OH)D3). Neonatal vitamin D status was significantly associated with the risk of ASDs and intellectual disability. The nature of those relationships was nonlinear.

The Inhibitory Effects of Purple Sweet Potato Color on Hepatic Inflammation Is Associated with Restoration of NAD+ Levels and Attenuation of NLRP3 Inflammasome Activation in High-Fat-Diet-Treated Mice

Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, exhibits beneficial effects on metabolic syndrome. Sustained inflammation plays a crucial role in the pathogenesis of metabolic syndrome. Here we explored the effects of PSPC on high-fat diet (HFD)-induced hepatic inflammation and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + PSPC group, and PSPC group. PSPC was administered by daily oral gavage at doses of 700 mg/kg/day for 20 weeks. Nicotinamide riboside (NR) was used to increase NAD+ levels. Our results showed that PSPC effectively ameliorated obesity and liver injuries in HFD-fed mice. Moreover, PSPC notably blocked hepatic oxidative stress in HFD-treated mice. Furthermore, PSPC dramatically restored NAD+ level to abate endoplasmic reticulum stress (ER stress) in HFD-treated mouse livers, which was confirmed by NR treatment. Consequently, PSPC remarkably suppressed the nuclear factor-κB (NF-κB) p65 nuclear translocation and nucleotide oligomerization domain protein1/2 (NOD1/2) signaling in HFD-treated mouse livers. Thereby, PSPC markedly diminished the NLR family, pyrin domain containing 3 (NLRP3) inflammasome activation, ultimately lowering the expressions of inflammation-related genes in HFD-treated mouse livers. In summary, PSPC protected against HFD-induced hepatic inflammation by boosting NAD+ level to inhibit NLRP3 inflammasome activation.

Protective effects of microRNA-431 against cerebral ischemia-reperfusion injury in rats by targeting the Rho/Rho-kinase signaling pathway

This study investigates the protective effects of miR‐431 against cerebral ischemia‐reperfusion injury through the Rho/Rho‐kinase signaling pathway. SD rats were randomly classified into normal, sham, and model (middle cerebral artery occluded) groups. Rho expression and cerebral infarction were visualized by immunohischemistry and TTC staining, respectively. qRT‐PCR and western blotting were used to measure mRNA and protein expression of miR‐431 and Rho/Rho‐kinase signaling pathway‐related genes. Hippocampal neurons were extracted and assigned into normal, blank, negative control (NC), miR‐431 mimics, miR‐431 inhibitors, siRNA‐Rho, and miR‐431 inhibitors + siRNA‐Rho groups. Proliferation and apoptosis were detected by MTT and flow cytometry, respectively. Compared with the normal group, the model group showed elevated Rho expression, area of cerebral infarction, and expressions of Rho/Rho‐kinase related genes but reduced miR‐431 expression. Compared with the blank group, expression of Rho, Rho‐kinase α, and Rho‐kinase β decreased and miR‐431 expression increased in the miR‐431 mimics and siRNA‐Rho groups, and the tendency reversed in the miR‐431 inhibitors group. Enhanced proliferation and inhibited apoptosis were exhibited in the miR‐431 mimics and siRNA‐Rho groups while results in the miR‐431 inhibitors group reversed. Findings obtained from this study indicated that miR‐431 confers protection against cerebral ischemia‐reperfusion injury through negatively regulating the Rho/Rho‐kinase signaling pathway.

Effects of long noncoding RNA SPRY4-IT1-mediated EZH2 on the invasion and migration of lung adenocarcinoma

We aim to investigate the interaction between the EZH2 and the long noncoding RNA (lncRNA) SPRY4‐IT1. We also explore their respective effects on human lung adenocarcinoma (LA) cell invasion and migration. Both LA and adjacent normal tissues were obtained from 256 LA patients. SPTY4‐IT expression and EZH2 mRNA expressions in tissues and cells were detected by reverse transcription quantitative polymerase chain reaction (RT‐qPCR). The siRNAs against SPRY4‐IT1 and EZH2 were co‐transfected into A549 and H1975 cells. The interaction between SPRY4‐IT1 and EZH2 was determined using a RNA pull‐down assay and a RNA immunoprecipitation (RIP) assay. A Transwell assay and scratch assay were used to evaluate the cell migration and invasion abilities. The expressions of E‐cadherin and Vimentin in the epithelial‐mesenchymal transition (EMT) and EZH2 protein expression were detected through western blotting. SPRY4‐IT1 expression was observed to be significantly lower, while the expression of EZH2 was higher in the LA tissues than in the adjacent normal tissues. Compared with the HBE cell line, expressions of SPRY4‐IT1 in each human LA cell line had decreased, with the lowest observed reduction in the A549 cell line, while EZH2 mRNA and protein expression increased in each human LA cell lines. After SPRY4‐IT1‐siRNA was transfected into A549 and H1975 cells, invasion and migration abilities were enhanced, in addition to a reduction in the expression of E‐cadherin, while expressions of Vimentin exhibited an increased rate. Consequently, we find that EZH2 promotes LA cell invasion and metastasis by inhibiting SPRY4‐IT1 expression.

Troxerutin Attenuates Enhancement of Hepatic Gluconeogenesis by Inhibiting NOD Activation-Mediated Inflammation in High-Fat Diet-Treated Mice

Recent evidence suggests that troxerutin, a trihydroxyethylated derivative of natural bioflavonoid rutin, exhibits beneficial effects on diabetes-related symptoms. Here we investigated the effects of troxerutin on the enhancement of hepatic gluconeogenesis in high-fat diet (HFD)-treated mice and the mechanisms underlying these effects. Mice were divided into four groups: Control group, HFD group, HFD + Troxerutin group, and Troxerutin group. Troxerutin was treated by daily oral administration at doses of 150 mg/kg/day for 20 weeks. Tauroursodeoxycholic acid (TUDCA) was used to inhibit endoplasmic reticulum stress (ER stress). Our results showed that troxerutin effectively improved obesity and related metabolic parameters, and liver injuries in HFD-treated mouse. Furthermore, troxerutin significantly attenuated enhancement of hepatic gluconeogenesis in HFD-fed mouse. Moreover, troxerutin notably suppressed nuclear factor-κB (NF-κB) p65 transcriptional activation and release of inflammatory cytokines in HFD-treated mouse livers. Mechanismly, troxerutin dramatically decreased Nucleotide oligomerization domain (NOD) expression, as well as interaction between NOD1/2 with interacting protein-2 (RIP2), by abating oxidative stress-induced ER stress in HFD-treated mouse livers, which was confirmed by TUDCA treatment. These improvement effects of troxerutin on hepatic glucose disorders might be mediated by its anti-obesity effect. In conclusion, troxerutin markedly diminished HFD-induced enhancement of hepatic gluconeogenesis via its inhibitory effects on ER stress-mediated NOD activation and consequent inflammation, which might be mediated by its anti-obesity effect.

LncRNA LINC00880 promotes cell proliferation, migration, and invasion while inhibiting apoptosis by targeting CACNG5 through the MAPK signaling pathway in spinal cord ependymoma

The present study was to investigate the effect of lncRNA LINC00880 targeting CACNG5 on cell proliferation, migration, invasion, and apoptosis in spinal cord ependymoma (SCE) through the MAPK signaling pathway. GEO database was used to download gene expression data related with SCE (GSE50161 and GSE66354) and annotation file. LncRNA with differential expression was predicted by Multi Experiment Matrix website (MEM). The target gene was analyzed by KEGG pathway enrichment analysis. SCE tissues and adjacent tissues were collected. The positive expression of CACNG5 protein was tested by immunohistochemistry. Expression of LINC00880, CACNG5, and MAPK signaling pathway‐related proteins was measured with qRT‐PCR and Western blotting. Cell proliferation, migration, invasion, cycle, and apoptosis were detected using MTT, Transwell assay, Scratch test, and Flow cytometry. SCE tissues showed increased LINC00880 expression. CACNG5 was a target gene of LINC00880 and correlated with MAPK signaling pathway. Compared with adjacent tissues, SCE tissues showed lower positive expression of CACNG5. Compared with the blank group, LINC00880 expression was higher in the LINC00880 vector and LINC00880 vector + CACNG5 vector groups, and lower in the si‐LINC00880 and si‐LINC00880 + si‐CACNG5 groups; in the LINC00880 vector and si‐CACNG5 groups, expression of survivin, p38MAPK, ERK1/2, JNK1/2/3 increased and CACNG5 and Bax expression reduced, the proliferation, invasion and migration of tumor cells increased, and apoptosis rate decreased. Opposite results were found in the si‐LINC00880 and CACNG5 vector groups. The findings indicate that lncRNA LINC00880 targeting CACNG5 inhibits cell apoptosis and promotes proliferation, migration, and invasion in SCE through the MAPK signaling pathway.

MicroRNA-421 suppresses the apoptosis and autophagy of hippocampal neurons in epilepsy mice model by inhibition of the TLR/MYD88 pathway

Epilepsy is a group of neurological disorders characterized by epileptic seizures. In this study, we aim to explore the role of microRNA‐421 (miR‐421) in hippocampal neurons of epilepsy mice via the TLR/MYD88 pathway. Forty mice were randomly served as the normal and model (established as epilepsy model) groups. Hippocampal neurons were assigned into seven groups with different transfections. The RT‐qPCR and western blotting were conducted to examine the expression of miR‐421 TLR2, TLR4, MYD88, Bax, Bcl‐2, p53, Beclin‐1, and LC3II/LC3I. Cell proliferation and apoptosis were detected by MTT and flow cytometry.MYD88 is a target gene of miR‐421. Model mice showed elevated expression of TLR2, TLR4, MYD88, Bax, p53, Beclin‐1, and LC3II/LC3I but reduced expression of miR‐421 and Bcl‐2. In vitro experiments reveals that overexpression of miR‐421 inhibited the TLR/MYD88 pathway. Besides, overexpressed miR‐421 declined cell apoptosis but increased cell proliferation. It reveals that miR‐421 targeting MYD88 could inhibit the apoptosis and autophagy of hippocampal neurons in epilepsy mice by down‐regulating the TLR/MYD88 pathway.

MicroRNA-433 inhibits oral squamous cell carcinoma cells by targeting FAK

We investigated the involvement of microRNA-433 (miR-433) in the proliferation, migration, and invasiveness of oral squamous cell carcinoma (OSCC). Totally 108 OSCC tissues and adjacent normal tissues from patients with OSCC were collected. Also, transplanted tumor formation experiment in nude mice was conducted to verify the effect of miR-433 and FAK on subcutaneous transplanted tumor. The CD44+ stem cell from SCC-9 were collected and assigned into the blank, miR-433 mimics, mimics control, miR-433 inhibitors, inhibitors control, siFAK and miR-433 inhibitors + siFAK groups. The qRT-PCR and western blotting were used to detect miR-433, FAK, ERK, MEK, pERK and pMEK after transfection. Flow cytometry, MTT assay, scratch test and Transwell assay were performed to determine the cell proportion, growth, migration and invasion of SCC-9 cells. In cell line SCC-9, expression of CD133, Oct-4, and BIM-1 was greater in CD44+ cells than CD44- cells, indicating that CD44+ cells had characteristics of tumor stem cells. Expression of FAK, ERK, MEK, p-ERK and p-MEK was decreased in tumor tissues from the CD44-, miR-433, and siFAK groups. Expression of MiR-433 mRNA was elevated, while levels of FAK, ERK, MEK, p-ERK, and p-MEK mRNA were all decreased in the miR-433 mimics group. In the miR-433 mimics and siFAK groups, cell proliferation, migration, and invasion were all decreased, while the opposite trends were seen in the miR-433 inhibitor group. These results indicate that miR-433 downregulates FAK through the ERK/MAPK signaling pathway to inhibit the proliferation, migration, and invasiveness of SCC-9 OSCC cells.