HDAC3 inhibition improves urinary-concentrating defect in hypokalaemia by promoting AQP2 transcription.

Aim: This study investigated whether enhanced histone acetylation, achieved by inhibiting histone deacetylases (HDACs), could prevent decreased aquaporin-2 (AQP2) expression during hypokalaemia.

Methods: Male Wistar rats were fed a potassium-free diet with or without 4-phenylbutyric acid (4-PBA) or the selective HDAC3 inhibitor RGFP966 for 4 days. Primary renal inner medullary collecting duct (IMCD) cells and immortalized mouse cortical collecting duct (mpkCCD) cells were cultured in potassium-deprivation medium with or without HDAC inhibitors.

Controlled delivery of quantum dots using microelectrophoresis technique: Intracellular behavior and preservation of cell viability.

The use of synthetic nanomaterials as contrast agents, sensors, and drug delivery vehicles in biological research primarily requires effective approaches for intracellular delivery. Recently, the well-accepted microelectrophoresis technique has been reported to exhibit the ability to deliver nanomaterials, quantum dots (QDs) as an example, into live cells, but information about cell viability and intracellular fate of delivered nanomaterials is yet to be provided. Here we show that cell viability following microelectrophoresis of QDs is strongly correlated with the amount of delivered QDs, which can be finely controlled by tuning the ejection duration to maintain long-term cell survival.

Mine Water Inrush Risk Assessment Evaluation Based on the GIS and Combination Weight-Cloud Model: A Case Study.

With the increase in mining depth, the hydrogeological conditions of mines become more complex, which leads to higher possibility and harmfulness of water inrush accidents and brings great challenges to mine safety. It is particularly important to accurately evaluate the risk of mine water inrush. In order to study and prevent the floor water disaster of coal mines, it is necessary to correctly evaluate the risk of water inrush according to the limited borehole data.

Whispering gallery mode excitation using exposed-core fiber.

Whispering gallery modes (WGMs) in micro-resonators are of interest due to their high Q-factors. Ultra-thin fiber tapers are widely deployed to couple light into micro-resonators but achieving stable and practical coupling for out-of-lab use remains challenging. Here, a new WGM coupling scheme using an exposed-core silica fiber (ECF) is proposed, which overcomes the challenge of using fragile fiber tapers.

GSK-3β inhibitor TDZD-8 prevents reduction of aquaporin-1 expression via activating autophagy under renal ischemia reperfusion injury.

Renal ischemia/reperfusion (I/R) injury is a main cause of acute kidney injury (AKI). Aquaporin (AQP)-1 water channel in the kidney is critical for the maintenance of water homeostasis and the urinary concentrating ability. Increasing evidence supports an important role of autophagy in the pathogenesis of AKI induced by renal I/R.

Cytoplasmic delivery of quantum dots via microelectrophoresis technique.

Nanoparticles with specific properties and functions have been developed for various biomedical research applications, such as in vivo and in vitro sensors, imaging agents and delivery vehicles of therapeutics. The development of an effective delivery method of nanoparticles into the intracellular environment is challenging and success in this endeavor would be beneficial to many biological studies. Here, the well-established microelectrophoresis technique was applied for the first time to deliver nanoparticles into living cells.

Activation of TGR5 restores AQP2 expression via the HIF pathway in renal ischemia-reperfusion injury.

Renal ischemia-reperfusion (I/R) injury is associated with markedly reduced protein expression of aquaporins (AQPs). Membrane G protein-coupled bile acid receptor-1 (TGR5) has shown protective roles in some kidney diseases. The purpose of the current study was to investigate whether activation of TGR5 prevented the decreased protein expression of AQPs in rodents with renal I/R injury and potential mechanisms.

Inhibition of IL-1β by Aliskiren Improved Renal AQP2 Expression and Urinary Concentration Defect in Ureteral Obstruction and Release.

We previously demonstrated that ureteral obstruction is associated with a urinary concentrating defect and reduced expression of renal aquaporins (AQPs), in which the renin-angiotensin system (RAS) may play an important role. The aims of the present study were to examine whether the renin inhibitor aliskiren could prevent the reduction in AQP expression and improve the urinary concentrating capacity in mice with bilateral ureteral obstruction (BUO) and BUO release. BUO was performed for 24 h, and BUO release was performed for 1 (B-R1D) or 3 days (B-R3D) with or without aliskiren treatment.

Bile Acid G Protein-Coupled Membrane Receptor TGR5 Modulates Aquaporin 2-Mediated Water Homeostasis.

Background: The bile acid-activated receptors, including the membrane G protein-coupled receptor TGR5 and nuclear farnesoid X receptor (FXR), have roles in kidney diseases. In this study, we investigated the role of TGR5 in renal water handling and the underlying molecular mechanisms.

Methods: We used tubule suspensions of inner medullary collecting duct (IMCD) cells from rat kidneys to investigate the effect of TGR5 signaling on aquaporin-2 (AQP2) expression, and examined the effects of TGR5 in mice with lithium-induced nephrogenic diabetes insipidus (NDI) and knockout () mice.

Hydrogen sulfide upregulates renal AQP-2 protein expression and promotes urine concentration.

Increasing evidence supports the important role of HS in renal physiology and the pathogenesis of kidney injury. Whether HS regulates water metabolism in the kidney and the potential mechanism are still unknown. The present study was conducted to determine the role of HS in urine concentration.

Combination exposure of melamine and cyanuric acid is associated with polyuria and activation of NLRP3 inflammasome in rats.

The molecular mechanisms of melamine-induced renal toxicity have not been fully understood. The purpose of the study aimed to investigate whether melamine and cyanuric acid induced NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation in the kidney, which may contribute to abnormal water and sodium handling in a rat model. Wistar rats received melamine (Mel; 200 mg·kg body wt·day), cyanuric acid (CA; 200 mg·kg body wt·day), or Mel plus CA (Mel + CA; 100 mg·kg body wt·day, each) for 2 wk.