Leptin reduces ventilator-induced lung injury in rats by regulating NLRP3, NLRC4 and NLRC3.

Leptin has been linked to acute lung injury (ALI) through its regulation of immune responses. We aimed to scrutinize the effects of leptin on nucleotide oligomerization domain-like receptors containing pyrin domain 3 (NLRP3), nucleotide oligomerization domain-like receptors with caspase activation and recruitment domain 4 (NLRC4), and nucleotide oligomerization domain-like receptors with caspase activation and recruitment domain 3 (NLRC3), as an essential part of the immune system, in ventilator-induced lung injury (VILI) of rats. In the present study, pathogen-free adult male SD rats were given saline or leptin, followed by ventilation. Lung tissue samples, bronchoalveolar lavage fluids (BALF), and blood were collected four hours after installation. Notable acute lung inflammation induced by mechanical ventilation is well-characterized by a massive increase in lung injury score and wet/dry weight (W/D) ratio. We also observed VILI was associated with interleukin (IL-1ß and IL-18). Rats that received ventilation showed a decrease in the levels of NLRP3 and NLRC4, and an increased level of NLRC3. Pre-treatment with leptin could abolish all of these effects induced by VILI. It has been suggested that the regulation of NLRP3, NLRC4, and NLRC3 may underlie the protection observed during VILI by exogenous leptin.

Inhibiting lncRNA ROR suppresses growth, migration and angiogenesis in microvascular endothelial cells by up-regulating miR-26.

OBJECTIVE: Lower extremity arteriosclerosis is one of leading causes of death worldwide. Arteriosclerosis is closely related to microvascular endothelial cells. This study was aimed to explore the role of long non-coding RNA ROR in regulations of growth, migration, and angiogenesis of microvascular endothelial cells. MATERIALS AND METHODS: Angiogenesis was determined by the number of tube-like cells on a matrigel extracellular matrix. Cell viability, apoptosis, and migration were determined by CCK-8 assay, PI/FITC-Annexin V staining method, and transwell assay, respectively. Relative RNA expression of ROR, miR-26, and angiogenesis-associated genes were analyzed by qRT-PCR. The protein expression of apoptosis- and angiogenesis-associated genes, as well as main factors in NF-κB and JAK1/STAT3 pathways, were analyzed by Western blot. RESULTS: LncRNA ROR silence inhibited viability, migration, and angiogenesis of HMEC-1 cells but promoted apoptosis of them. miR-26 expression was promoted after knocking down ROR expression. miR-26 overexpression enhanced the inhibitory effects of ROR silence on growth, migration, and angiogenesis in HMEC-1 cells, whereas, miR-26 silence impaired the effects of ROR silence. Finally, we found that NF-κB and JAK1/STAT3 signaling pathways were inhibited by ROR down-regulation. Similarly, miR-26 overexpression enhanced the inhibitory effect of ROR down-regulation on the pathways and miR-26 inhibition abrogated it. CONCLUSIONS: Down-regulating lncRNA ROR inhibited growth, migration and angiogenesis of microvascular endothelial cells possibly through up-regulation of miR-26. During this process, the activations of NF-κB and JAK1/STAT3 pathways were inhibited after interaction of ROR and miR-26.

Visualizing dopamine released from living cells using a nanoplasmonic probe.

We report the development of an ultrasensitive nanoplasmonic probe for discriminative detection and imaging of dopamine released from living cells. The sensing mechanism is based on the dopamine-induced seeded-growth of Au nanoparticles (Au NPs) that leads to the shift of the plasmon band. This platform allows for the detection of dopamine with a detection limit down to 0.25 pM within 1 min. This nanoplasmonic assay is further applied to visualize the release of dopamine from living rat pheochromocytoma (PC12) cells under ATP-stimulation with dark-field microscopy (DFM). The DFM results together with real time fluorescence imaging of PC12 cells stained with the Fluo calcium indicator, suggested that ATP stimulated-release of dopamine is concomitant with the Ca(2+) influx, and the influx of Ca(2+) is through ATP-activated channels instead of the voltage-gated Ca(2+) channel (VGC).

Determination of proteins by fluorescence quenching of Magdala Red.

Magdala Red (MR) binding to protein causes a decrease in the fluorescence intensity of MR at 556 nm. Based on this, a new quantitative determination method for proteins is developed. The linear range of this assay is 0.1-4.0 microg ml(-1) of Bovine Serum albumin (BSA). The measurements can be made easily on a common fluorimeter. The reaction between MR and proteins is completed in 1 min, and the fluorescence intensity is stable for at least 2 h. There is little or no interference from amino acids and most metal ions. The proposed method has been applied to the determination of protein in milk powder and soybean milk powder and the results are in agreement with the results by the other methods.