Zebularine protects against blood-brain-barrier (BBB) disruption through increasing the expression of zona occludens-1 (ZO-1) and vascular endothelial (VE)-cadherin.

Blood-brain-barrier (BBB) disruption is an important pathological characteristic of ischemic stroke (IS) and mainly results from dysfunction of brain vascular endothelial cells and tight junctions. Zebularine is a novel inhibitor of DNA methyltransferase (DNMT). Here, we assessed its effects on BBB disruption in IS. Firstly, we reported that Zebularine maintained BBB integrity in middle cerebral artery occlusion (MCAO) mice by increasing the expressions of zona occludens-1 (ZO-1) and vascular endothelial (VE)-cadherin. Importantly, we found that Zebularine reduced the production of pro-inflammatory cytokines, attenuated brain edema, and improved neurological deficits. In in vitro experiments, the bEnd.3 brain endothelial cells were exposed to oxygen and glucose deprivation/reoxygenation (OGD/R), and the protective effects of Zebularine were assessed. Our findings demonstrated that Zebularine prevented OGD/R-induced cytotoxicity by reducing the release of lactate dehydrogenase (LDH). Additionally, Zebularine protected bEnd.3 cells against OGD/R-induced hyper-permeability and reduction of trans-endothelial electrical resistance (TEER). Notably, we found that treatment with Zebularine activated the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway by increasing the phosphorylation of adenosine monophosphate-activated protein kinase α (AMPKα). Blockage of AMPKα using its specific inhibitor compound C abolished the beneficial effects of Zebularine in mitigating endothelial hyper-permeability by reducing the expressions of ZO-1 and VE-cadherin. These findings suggest that the protective effects of Zebularine against OGD/R-induced endothelial hyper-permeability are mediated by the activation of AMPKα. In conclusion, our study sheds light on the potential application of Zebularine in the treatment of IS.

Stilbene glycoside upregulates SIRT3/AMPK to promotes neuronal mitochondrial autophagy and inhibit apoptosis in ischemic stroke.

BACKGROUND: Ischemic stroke, also known as cerebrovascular accident or cerebral stroke, occupies the first place in the world's top 10 causes of death, with high incidence, mortality and disability rates. OBJECTIVES: To investigate the effect of stilbene glycoside upregulated SIRT3/AMPK expression on neuronal mitochondrial autophagy and neuronal apoptosis in ischemic stroke. MATERIAL AND METHODS: The PC12 cells were cultured without serum to construct an ischemic neuron model. The cells were divided into 6 groups: normal group (untreated cells), model group (ischemic treated cells), TSG group (stilbene glycoside treatment), NC group (SIRT3 and AMPK negative control treatment), si-SIRT3 group (SIRT3 silencing treatment), TSG+si-SIRT3 group (joint treatment), and TSG+si-SIRT3+oe-AMPK group (joint treatment). Cell survival and the expression of related molecules were detected. RESULTS: Compared with normal group, the model group had significantly decreased cell survival rate, mitochondrial membrane potential, as well as the expression of Bcl-2, LC3II/I, P62, PINK1, Parkin, SIRT3, AMPK, and p-AMPK, while showing significantly increased proportion of apoptosis and the expression of caspase 3 and Bax. Compared with the model group, TSG treatment promoted cell survival rate and mitochondrial autophagy, and inhibited apoptosis, while SIRT3 silencing treatment reduced cell survival rate and mitochondrial autophagy, and increased apoptosis. The SIRT3 silencing could block the inhibitory effect of TSG on the apoptosis of ischemic PC12 cells and promote mitochondrial autophagy, and AMPK overexpression could save the apoptosis of ischemic PC12 cells caused by SIRT3 silencing, and promote mitochondrial autophagy. CONCLUSIONS: By promoting the expression of SIRT3/AMPK, TSG promotes mitochondrial autophagy in ischemic neurons and inhibits their apoptosis.

MicroRNA-210 protects against periodontitis through targeting HIF-3α and inhibiting p38MAPK/NF-κB pathway.

The aim of this study was to investigate the effects of miR-210 abnormal expression on Porphyromonas gingivalis lipopolysaccharide (LPS)-treated primary human periodontal ligament cells (PDLCs). The miR-210 level was identified in gingival tissues from patients with chronic periodontitis (CP) and healthy subjects as well as LPS-treated PDLCs by qRT-PCR. Cell viability, apoptotic cells, expression of proteins associated with apoptosis, and release of inflammatory factors in LPS-treated PDLCs were measured using MTT assay, flow cytometry assay, western blotting and ELISA, respectively. Effects of miR-210 abnormal expression on cell viability, cell apoptosis and inflammation factors in LPS-treated PDLCs were evaluated. Afterwards, the target gene of miR-210 was identified, and the involvement of p38MAPK/NF-κB pathway with the effects of miR-210 was finally studied. The miR-210 level was significantly down-regulated in gingival tissues from CP patients as well as LPS-treated PDLCs. LPS-induced decrease of cell viability, increase of apoptosis, and release of TNF-α, IL-1ß, IL-6 and IL-8 were attenuated by miR-210 overexpression. We found that hypoxia-inducible factor (HIF)-3α was a target of miR-210, and HIF-3α overexpression partly reversed the effects of miR-210 up-regulation on cell viability, cell apoptosis and inflammation factors expression in LPS-treated PDLCs. Moreover, the phosphorylation levels of key kinases in the NF-κB and p38MAPK pathways were reduced by miR-210 via targeting HIF-3α in LPS-treated PDLCs. MiR-210 attenuated LPS-induced periodontitis, and the LPS-induced activation of the NF-κB and p38MAPK pathways was attenuated by miR-210 via targeting HIF-3α in PDLCs.

Numerical Response Surfaces of Volume of Ablation and Retropulsion Amplitude by Settings of Ho:YAG Laser Lithotripter.

Objectives: Although laser lithotripsy is now the preferred treatment option for urolithiasis due to shorter operation time and a better stone-free rate, the optimal laser settings for URS (ureteroscopic lithotripsy) for less operation time remain unclear. The aim of this study was to look for quantitative responses of calculus ablation and retropulsion by performing operator-independent experiments to determine the best fit versus the pulse energy, pulse width, and the number of pulses. Methods: A lab-built Ho:YAG laser was used as the laser pulse source, with a pulse energy from 0.2 J up to 3.0 J and a pulse width of 150 µs up to 1000 µs. The retropulsion was monitored using a high-speed camera, and the laser-induced craters were evaluated with a 3-D digital microscope. The best fit to the experimental data is done by a design of experiment software. Results: The numerical formulas for the response surfaces of ablation speed and retropulsion amplitude are generated. Conclusions: The longer the pulse, the less the ablation or retropulsion, while the longer pulse makes the ablation decrease faster than the retropulsion. The best quadratic fit of the response surface for the volume of ablation varied nonlinearly with pulse duration and pulse number.