Neuroprotective Effects of Long-Term Metformin Preconditioning on Rats with Ischemic Brain Injuries.

INTRODUCTION: This study is to analyze the neuroprotective effects of long-term metformin (Met) preconditioning on rats with ischemic brain injuries and the related mechanisms. METHODS: Twenty-five Sprague-Dawley rats were randomly divided into 5 groups: sham group, middle cerebral artery occlusion (MCAO) group, normal saline + MCAO group, pre- Met + MCAO group, and 3-MA + Met + MCAO group. Pathological changes of brain were observed by hematoxylin-eosin staining. Neurobehavior scores were calculated. Infarct area was assessed by 2,3,5-triphenyltetrazolium chloride staining. Apoptosis of neurons was detected by TdT-mediated dUTP Nick-End Labeling (TUNEL). Western blot tested the expression of LC3 (microtubule-associated protein 1 light chain 3), Beclin-1, adenosine 5'-monophosphate ([AMP]-activated protein kinase [AMPK]), and p-AMPK in hippocampal CA1 region. RESULTS: Compared with the sham group, the MCAO group induced severe pathological changes in the brain. The neurobehavior scores and infarct area in the brain were increased in the MCAO group than in the sham group. The apoptosis level in the MCAO group was also higher than in the sham group. However, after pretreatment with Met, the pathological changes in the brain were attenuated. Compared with the MCAO group, the pre-Met + MCAO group also had decreased neurobehavior scores and infarct area in the brain. Additionally, the apoptosis level in the pre-Met + MCAO group was lower than in the MCAO group. Moreover, the MCAO group had increased levels of LC3 and Beclin-1 than in the sham group. In the pre-Met + MCAO group, their levels were decreased than in the MCAO group. The p-AMPK level in the pre-Met + MCAO group was also increased than in the MCAO group, suggesting activation of p-AMPK by Met. CONCLUSION: Long-term Met pretreatment has neuroprotective effect on ischemic brain injury, which may be related to the regulation of autophagy-related protein expression and apoptosis.

Angelica sinensis is effective in treating diffuse interstitial pulmonary fibrosis in rats.

The aim of this study was to investigate the therapeutic effect of Angelica sinensis on a rat model of diffuse interstitial pulmonary fibrosis induced by bleomycin A5. The mechanism by which A. sinensis exerts its effect is also discussed. A diffuse interstitial pulmonary fibrosis model was established in 36 male Wistar rats by an endotracheal injection of bleomycin A5 (5 mg/kg). Then, these rats were randomly divided into the model group (n = 18) and the treatment group (treated with A. sinensis after modelling, n = 18). Control rats (n = 6) received an equal volume of saline. Hematoxylin-eosin (HE) staining was performed to analyse alveolitis and Masson staining, to observe pulmonary fibrosis. Collagen content was determined by hydroxyproline assay. Nuclear factor kappa B (NF-κB) activity was measured by electrophoretic mobility shift assay. Transforming growth factor-ß (TGF-ß) expression at mRNA level was detected by northern blotting and at protein level by enzyme-linked immunosorbent assay. The results obtained showed that the alveolitis and pulmonary fibrosis of the rats treated with A. sinensis was significantly alleviated compared with that of the rats in the model group. Treatment with A. sinensis also lowered the content of collagen, decreased NF-κB activity in alveolar macrophages and reduced the TGF-ß expression at the mRNA and protein level. These results indicated that A. sinensis is effective in treating and alleviating interstitial pulmonary fibrosis, possibly by lowering collagen, inhibiting the activity of NF-κB and reducing the TGF-ß expression.

Variances of quantifying of Virchow-Robin spaces detecting the different functional status of glymphatic system in simple febrile seizures affected by seizures duration.

The Virchow-Robin spaces (VRs) in the cerebral glymphatic system play a vital role in waste clearance from the brain. Simple febrile seizures (SFS) are a common type of seizures marked by an inappropriate fluid exchange. The mechanism of evident differences in glymphatic function among SFS with varying seizure duration is unknown. Therefore, the goal of this study was to see whether there were any variations in glymphatic function among SFS based on seizures duration. We retrospectively studied 30 children with SFS lasting more than 5 minutes (SFS > 5M), 40 children with SFS lasting 5 minutes or less (SFS ≤ 5M), and 35 healthy controls aged 6 to 60 months who underwent magnetic resonance imaging (MRI). A custom-designed automated method that used T2-weighted imaging (T2WI) to segment the visible VRs. The VRs metrics were measured and compared studied groups. The VRs metrics, seizure duration the time gap between seizure onset and MRI scan were studied as well. VRs counts were lower (P < .001) in the SFS ≤ 5M (445.80 ±â€…66.10) and the control (430.77 ±â€…182.55) groups in comparison to SFS > 5M (642.70 ±â€…100.62). Similar results were found for VRs volume (VRsvol_SFS > 5M, 8514.63 ±â€…835.33mm3, VRsvol_SFS ≤ 5M, 6390.43 ±â€…692.74 mm3, VRsvol_control, 6048.37 ±â€…111.50 mm3; P < .001). However, in the SFS ≤ 5M, VRs measurements were lower than in the SFS > 5M (P < .001). VRs measurements were positively connected with seizure duration and inversely correlated with the course following seizure onset and MRI scan time in both SFS groups. SFS are positively correlated to glymphatic dysfunction since they cause enlarged VRs; additionally, VRs can be used as a biomarker in SFS > 5M and contribute to the mechanism.

Children with autism spectrum disorder present glymphatic system dysfunction evidenced by diffusion tensor imaging along the perivascular space.

This study used diffusion tensor imaging (DTI) along the perivascular space (DTI-ALPS) to assess glymphatic system function in autism spectrum disorder (ASD) compared to healthy controls. Patients with ASD may have glymphatic system dysfunction, which is related to age. We retrospectively included 30 children with ASD and 25 healthy controls in this study. 3T magnetic resonance imaging scanner was used to perform DTI magnetic resonance imaging on all participants, and the DTI-ALPS index was calculated from the DTI data. Additionally, we evaluated how the DTI-ALPS index differed between the 2 groups. Moreover, we examined the relationships between the bilateral DTI-ALPS index and the age of the participants. The DTI-ALPS index considerably differed between groups. In the left index (1.02 ±â€…0.12 vs. 1.27 ±â€…0.25, P < .001) and in the right index (1.03 ±â€…0.12 vs. 1.32 ±â€…0.20, P < .001), the DTI-ALPS in ASD patients was significantly lower than that in healthy controls. Furthermore, the DTI-ALPS index was strongly and positively associated with age. In patients with ASD, there is a glymphatic system dysfunction. This is intimately correlated to age. Our findings suggest the importance of the DTI-ALPS approach in assessing the function of the glymphatic system in ASD.

Neuroprotective effects of metformin on cerebral ischemia-reperfusion injury by regulating PI3K/Akt pathway.

Metformin (Met) is a commonly used drug in the treatment of type 2 diabetes. Currently, it has been found that Met can effectively reduce the incidence of stroke and exert anti-inflammatory effects. However, its role in ischemia-reperfusion (I/R)-induced nerve injury remains unclear. This study aims to investigate the neuroprotective effects of Met in I/R-induced neuron injury as well as the underlying mechanism. A middle cerebral artery occlusion (MCAO) model was established in Sprague Dawley (SD) rats, which were then treated with different doses of Met. Neurological deficits of rats were measured at different times post-surgery. TTC staining was done to observe the volume of cerebral infarction. HE staining was performed to observe pathological changes of brain tissues. Immunohistochemistry was performed to observe the expression of inflammatory factors in the cerebral tissues. qRT-PCR method was used to detect the relative expression of PI3K, Akt mRNA in cells after 24 h of drug action. Western blot method was used to detect the expression of PI3K, p-PI3K, Akt, and p-Akt in hippocampus. What is more, in vitro experiments were performed on BV2 microglia to verify the role of Met against oxygen-glucose deprivation (OGD). As a result, Met dose-dependently attenuated neurological deficits and neuronal apoptosis. Besides, Met administration also significantly reduced BV2 cells apoptosis and inflammatory response. Mechanistically, Met inactivated PI3K/Akt pathway induced by I/R and OGD, while it upregulated PI3K. In conclusion, Met protected rats from cerebral I/R injury via reducing neuronal apoptosis and microglial inflammation through PI3K/Akt pathway.

Serum miR-100 is a potential biomarker for detection and outcome prediction of glioblastoma patients.

BACKGROUND: It is well known that some circulating microRNAs (miRNAs) are highly stable and might serve as promising biomarkers for many types of human cancer including glioblastoma (GBM). However, the potential clinical significance of serum miR-100 in GBM remained unknown. OBJECTIVE: We aimed to detect the expression level of serum miR-100 in patients with GBM and assess its potential diagnostic and prognostic value. METHODS: Quantitative real-time PCR was performed to measure serum miR-100 levels in 95 GBM patients and 60 healthy volunteers. The association between serum miR-100 level and clinicopathological parameters as well survival of GBM patients was evaluated. RESULTS: Our results revealed that serum miR-100 levels were significantly decreased in GBM patients compared with the healthy controls. Additionally, miR-100 levels were significantly elevated after treatment. Low miR-100 expression was closely correlated with worse clinicopathological characteristics. Further receiver operating characteristic (ROC) curve analysis showed that serum miR-100 could effectively discriminate GBM cases from normal controls. Moreover, survival analyses revealed that patients with high serum miR-100 levels had significantly longer survival time than those with low serum miR-100 levels. Finally, multivariate analysis identified serum miR-100 as an independent prognostic indicator for GBM. CONCLUSIONS: Our findings suggested that serum miR-100 might serve as promising biomarker for GBM diagnosis and prognosis.

Premature rupture of the fetal membrane combined with subclinical chorioamnionitis negatively affects pregnancy outcomes by a mechanism associated with reduced levels of matrix metalloproteinase-2.

The present study aimed to investigate whether premature rupture of the fetal membrane, combined with subclinical chorioamnionitis, affects pregnancy outcomes. In addition, the association between premature rupture of the fetal membrane (PROM) and the levels of matrix metalloproteinase-2 (MMP-2), an inactive proenzyme that can be activated by other factors or signals in humans, was examined. In total, 80 pregnant patients with PROM were classified into the experimental and control groups, according to their final placental pathological diagnosis results. The 40 patients in the experimental group suffered from subclinical chorioamnionitis, while the 40 patients in the control group exhibited no lesions of the placenta or fetal membrane. Tissue samples were collected and the total protein and mRNA were extracted for western blot and quantitative polymerase chain reaction analyses. ELISA was performed in order to detect the levels of MMP-2 in the serum of the two groups of patients. The rates of cesarean section, puerperal infection, postpartum hemorrhage, preterm incidence, placenta accreta, residual placental blood and stillbirth were all significantly higher in the experimental group compared with the control group. In addition, the mRNA and protein expression levels of MMP-2 were reduced in the experimental group compared with the control group. ELISA results indicated that the serum MMP-2 concentrations were also reduced in the patients with PROM. Therefore, the present study demonstrated that the PROM, combined with subclinical chorioamnionitis, significantly affected pregnancy outcomes and was associated with reduced levels of MMP-2.

Effects of paroxetine on spatial memory function and protein kinase C expression in a rat model of depression.

The aim of the present study was to investigate the effects of paroxetine on the spatial memory and expression level of protein kinase C (PKC) in a rat model of depression. Rat models of depression were established by chronic unpredictable mild stress. The spatial learning and memory function of the rats were assessed by the Morris water maze test. The expression levels of PKC in the hippocampus were detected by western blotting. The results showed that, compared with the control group, the escape latency was prolonged and the percentage of time in the target quadrant and the number of times the rats crossed the platform were reduced in the model group; however, the impaired spatial learning and memory function in these rat models could be restored by paroxetine, almost to a level comparable with that in the normal control animals. In addition, the expression of PKC in the model group was significantly decreased compared with that in the control group, and the expression could also be elevated by paroxetine treatment. These results suggest an association between PKC levels and the pathogenesis of depression. The application of paroxetine can improve the spatial memory and reverse the changes in PKC levels in the hippocampus in the rat model of depression. The present findings have enhanced the understanding of the pathogenesis of depression, and provide experimental evidence for the treatment of depression with paroxetine.

Expression and significance of MMP-7, c-Jun and c-Fos in rats skin photoaging.

OBJECTIVE: To investigate the expression and significance of the MMP-7, c-Jun and c-Fos in rat photoaging skin. METHODS: A total of 45 SD rats were randomly divided into control group, model group, natural recovery group, physiological saline injection group and dermal pluripotent stem cells transplantation (DMSCs group), model group, natural recovery group, physiological saline injection group. DMSCs were treated with UV lamp irradiation to establish light aging skin model. Rats were then sacrificed after model prepared, no treatment was processed in the natural recovery group. Saline injections was adopted in saline group, DESCs group was treated with DESCs transplantation. Rats were sacrificed after 4 weeks. The expression of MMP-7, c-Jun and c-Fos were detected using the immunohistochemical method. RESULTS: In model group, MMP 7 positive expression was higher than that in the other 4 groups, but without statistically difference (P>0.05); c-Jun, c-Fos expression were higher than that in the control group and DESCs group (P<0.05), there was no significant difference comparing natural recovery group with physiological saline injection group (P>0.05). CONCLUSIONS: MMP-7, c-Jun and c-Fos can be used as diagnosis indicators in the early stage of light aging, and they jointly participate in its development. DMSCs transplants is effective in treating light aging skin.