Search Results (5)

Rhabdomyolysis is a severe condition that commonly leads to acute kidney injury (AKI), with limited targeted treatments for rhabdomyolysis-induced AKI (RIAKI) adding to the challenge. Emerging evidence implicates nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) in the pathological processes of various kidney diseases, but its role in RIAKI remains unclear. We applied renal tubular epithelial cell (RTEC)-specific NOX4 knockout and the NOX4 inhibitor GKT137831 to treat RIAKI in vivo and in vitro. We found that genetic and pharmacological inhibition of NOX4 protected against glycerol-induced renal dysfunction, mitigated inflammatory responses and attenuated apoptotic rates. Additionally, NOX4 blockade suppressed the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), and enhanced the activities of antioxidant enzymes. Furthermore, NOX4 inhibition reduced the expression of endoplasmic reticulum stress (ERS)-associated proteins at both the RNA and protein levels. Collectively, these findings demonstrate that genetic and pharmacological suppression of NOX4 protects against RIAKI by reducing ROS generation, boosting antioxidant defense and inhibiting ERS activation. NOX4 inhibition may offer a potential approach for developing new treatment options for RIAKI. Full article

The respiratory activities of mitochondrial complexes I, II, and IV were analyzed in permeabilized Rhodotorula mucilaginosa cells and isolated mitochondria, and the kinetic parameters K_0.5 and V_max were obtained. No difference in substrate affinities were found between mitochondria and permeabilized cells. The activities of the components of the mitochondrial respiratory chain of the Antarctic yeast R. mucilaginosa M94C9 were identified by in-gel activity and SDS-PAGE. The mitochondria exhibited activity for the classical components of the electron transport chain (Complexes I, II, III, and IV), and supercomplexes were formed by a combination of the respiratory complexes I, III, and IV. Unfortunately, the activities of the monomeric and dimeric forms of the F1F0-ATP synthase were not revealed by the in-gel assay, but the two forms of the ATP synthase were visualized in the SDS-PAGE. Furthermore, two alternative pathways for the oxidation of cytosolic NADH were identified: the alternative NADH dehydrogenase and the glycerol-3-phosphate dehydrogenase. In addition, an NADPH dehydrogenase and a lactate cytochrome b2 dehydrogenase were found. The residual respiratory activity following cyanide addition suggests the presence of an alternative oxidase in cells. Full article

An electrochemical biosensor based on chitosan- and thioctic-acid-modified nanoporous gold (NPG) co-immobilization glycerol kinase (GK) and glycerol-3-phosphate oxidase (GPO) was constructed for glycerol determination in wine. The NPG, with the properties of porous microstructure, large specific surface area, and high conductivity, was beneficial for protecting the enzyme from inactivation and denaturation and enhancing electron transfer in the modified electrode. The co-immobilization of the enzyme by chitosan-embedding and thioctic-acid-modified NPG covalent bonding was beneficial for improving the catalytic performance and stability of the enzyme-modified electrode. Ferrocene methanol (Fm) was used as a redox mediator to accelerate the electron transfer rate of the enzyme-modified electrode. The fabricated biosensor exhibited a wide determination range of 0.1–5 mM, low determination limit of 77.08 μM, and high sensitivity of 9.17 μA mM⁻¹. Furthermore, it possessed good selectivity, repeatability, and stability, and could be used for the determination of glycerol in real wine samples. This work provides a simple and novel method for the construction of biosensors, which may be helpful to the application of enzymatic biosensors in different determination scenarios. Full article

Perennials utilize complex adaptive strategies and molecular mechanisms to cope with water-deficit conditions. Hence, in order to gain molecular insights regarding water-deficit stress, two-year-old coconut seedlings of the varieties Kalpa Sree and Kalpatharu were subjected to soil water-deficit regimes (25% of available of soil moisture and control). The biochemical, physiological and growth parameters underlying water-deficit stress revealed the differential enzymatic anti-oxidants, lipid peroxidation status and water use efficiency traits between the genotypes investigated. The entire plant water use efficiency at the control condition was significantly low in Kalpatharu (4.06) compared to in Kalpa Sree (4.74). Nevertheless, under severe stress (25% ASM), Kalpatharu exhibited the highest WUE (5.68) against dwarf variety Kalpa Sree (3.84). Furthermore, the leaf transcriptome profiles of the control and water-deficit stressed seedlings were examined by utilizing paired-end RNA-Seq. In total, ~7300 differentially expressed genes have been identified between the seedlings under water-deficit stress and control. Analysis of control and stressed Kalpasree leaf transcriptome showed significant upregulation of PHLOEM PROTEIN 2-LIKE A1-like, WRKY transcription factor 40 isoform X1 and downregulation of glycerol-3-phosphate acyltransferase 3 transcripts. On the other hand, the upregulation of transcripts encoding polyamine oxidase, arabinose 5-phosphate isomerase among others and downregulation of aquaporin PIP1-2 transcript was documented in Kalpatharu leaves. Moreover, long non-coding RNA and genic SSRs were also identified from the transcriptome data to further enrich the genomic resources of coconut palm, which could pave way for its utilization in developing climate-smart coconut crop. The implications of this study in molecular dissection of the adaptive response of coconut to the soil-water deficit are also discussed. Full article

A single use, disposable iridium-nano particle contained biosensor had been developed for the determination of diglyceride (DG). In this study hydrogen peroxide, formed through the enzymatic breakdown of DG via lipase, glycerol kinase and glycerol 3-phosphate oxidase, was electrochemically oxidized at an applied potential of +0.5 V versus the Ag/AgCl reference electrode. The oxidation current was then used to quantify the diglyceride concentration. Optimum enzyme concentrations and the surfactant loading used were established for successful sensor response. Good linear performance was observed over a DG concentration range of 0 to 25 µM in phosphate buffer and bovine serum media. Full article