ABSTRACT
Metabolic reprogramming mediates antibiotic efficacy. However, metabolic adaptation of microbes evolving from antibiotic sensitivity to resistance remains undefined. Therefore, untargeted metabolomics was conducted to unveil relevant metabolic reprogramming and potential intervention targets involved in gentamicin resistance. In total, 61 metabolites and 52 metabolic pathways were significantly altered in gentamicin-resistant E. coli. Notably, the metabolic reprogramming was characterized by decreases in most metabolites involved in carbohydrate and amino acid metabolism, and accumulation of building blocks for nucleotide synthesis in gentamicin-resistant E. coli. Meanwhile, fatty acid metabolism and glycerolipid metabolism were also significantly altered in gentamicin-resistant E. coli. Additionally, glycerol, glycerol-3-phosphate, palmitoleate, and oleate were separately defined as the potential biomarkers for identifying gentamicin resistance in E. coli. Moreover, palmitoleate and oleate could attenuate or even abolished killing effects of gentamicin on E. coli, and separately increased the minimum inhibitory concentration of gentamicin against E. coli by 2 and 4 times. Furthermore, palmitoleate and oleate separately decreased intracellular gentamicin contents, and abolished gentamicin-induced accumulation of reactive oxygen species, indicating involvement of gentamicin metabolism and redox homeostasis in palmitoleate/oleate-promoted gentamicin resistance in E. coli. This study identifies the metabolic reprogramming, potential biomarkers and intervention targets related to gentamicin resistance in bacteria.
Subject(s)
Anti-Bacterial Agents , Drug Resistance, Bacterial , Escherichia coli , Fatty Acids, Monounsaturated , Gentamicins , Oleic Acid , Gentamicins/pharmacology , Gentamicins/metabolism , Escherichia coli/metabolism , Escherichia coli/drug effects , Escherichia coli/genetics , Oleic Acid/metabolism , Oleic Acid/pharmacology , Drug Resistance, Bacterial/drug effects , Anti-Bacterial Agents/pharmacology , Fatty Acids, Monounsaturated/metabolism , Fatty Acids, Monounsaturated/pharmacology , Microbial Sensitivity Tests , Metabolomics/methods , Metabolic Networks and Pathways/drug effects , Reactive Oxygen Species/metabolism , Up-Regulation/drug effectsABSTRACT
Salidroside (SAL) is a phenol glycoside compound found in plants of the Rhodiola genus which has natural antioxidant and free radical scavenging properties. SAL are able to protect against manganese-induced ototoxicity. However, the molecular mechanism by which SAL reduces levels of reactive oxygen species (ROS) is unclear. Here, we established an in vitro gentamicin (GM) ototoxicity model to observe the protective effect of SAL on GM-induced hair cells (HC) damage. Cochlear explants of postnatal day 4 rats were obtained and randomly divided into six groups: two model groups (treatment with 0.2 mM or 0.4 mM GM for 24 h); two 400 µmol/L SAL-pretreated groups pretreatment with SAL for 3 h followed by GM treatment (0.2 mM or 0.4 mM) for 24 h; 400 µmol/L SAL group (treatment with SAL for 24 h); control group (normal cultured cochlear explants). The protective effects of SAL on GM-induced HC damage, and on mRNA and protein levels of antioxidant enzymes were observed. HC loss occurred after 24 h of GM treatment. Pretreatment with SAL significantly reduced GM-induced OHC loss. In cochlear tissues, mRNA and protein levels of NRF2 and HO-1 were enhanced in the GM alone group compared with the SAL pretreatment GM treatment group. SAL may protect against GM-induced ototoxicity by regulating the antioxidant defense system of cochlear tissues; SAL can activate NRF2/HO-1 signaling, inhibit NF-κB activation, activate AKT, and increase inhibitory phosphorylation of GSK3ß to decrease GSK3 activity, all of which exert antioxidant effects.
Subject(s)
Gentamicins , Glucosides , Ototoxicity , Rats , Animals , Gentamicins/toxicity , Gentamicins/metabolism , NF-kappa B/metabolism , Antioxidants/pharmacology , Antioxidants/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Glycogen Synthase Kinase 3/metabolism , Hair Cells, Auditory , Cochlea/metabolism , Phenols/pharmacology , Phenols/metabolism , RNA, Messenger/metabolismABSTRACT
Investigation the protective effect of transient receptor potential channel modulator 2-Aminoethoxydiphenyl Borate (2-APB) on aminoglycoside nephrotoxicity caused by reactive oxygen species, calcium-induced apoptosis and inflammation was aimed. Forty Wistar rats were divided (n=8) as follows: Control group; DMSO group; 2-APB group; Gentamicin group (injected 100 mg/kg gentamicin intramuscularly for 10 days); Gentamicin+ 2-APB group (injected 2 mg/kg 2-APB intraperitoneally, then after 30 minutes 100 mg/kg gentamicin was injected intramuscularly for 10 days). Blood samples were collected for biochemical analyses, kidney tissue samples were collected for light, electron microscopic and immunohistochemical investigations. In gentamicin group glomerular degeneration, tubular dilatation, vacuolization, desquamation of tubular cells and hyaline cast formation in luminal space and leukocyte infiltration were seen. Disorganization of microvilli of tubular cells, apical cytoplasmic blebbing, lipid accumulation, myelin figure like structure formation, increased lysosomes, mitochondrial swelling and disorganization of cristae structures, apoptotic changes and widening of intercellular space were found. TNF-α, IL-6 and caspase 3 expressions were increased. BUN and creatinine concentrations were increased. Increase in MDA levels and decrease in SOD activities were determined. Even though degeneration still continues in gentamicin+2-APB treatment group, severity and the area it occupied were decreased and the glomerular and tubule structures were generally preserved. TNF-α, IL-6, caspase 3 immunoreactivities and BUN, creatinine, MDA concentrations were reduced and SOD activities were increased markedly compared to gentamicin group. In conclusion, it has been considered that 2-APB can prevent gentamicin mediated nephrotoxicity with its anti-oxidant, anti-apoptotic and anti-inflammatory effects.
Subject(s)
Kidney Diseases , Kidney , Rats , Animals , Caspase 3/metabolism , Caspase 3/pharmacology , Aminoglycosides/adverse effects , Aminoglycosides/metabolism , Rats, Wistar , Creatinine/metabolism , Creatinine/pharmacology , Tumor Necrosis Factor-alpha , Interleukin-6 , Kidney Diseases/chemically induced , Kidney Diseases/prevention & control , Anti-Bacterial Agents/adverse effects , Antioxidants/pharmacology , Gentamicins/toxicity , Gentamicins/metabolism , Superoxide Dismutase/metabolism , Oxidative StressABSTRACT
Gentamicin (GM) is one of the commonly used antibiotics in the aminoglycoside class but is ototoxic, which constantly impacts the quality of human life. Pyrroloquinoline quinone (PQQ) as a redox cofactor produced by bacteria was found in soil and foods that exert an antioxidant and redox modulator. It is well documented that the PQQ can alleviate inflammatory responses and cytotoxicity. However, our understanding of PQQ in ototoxicity remains unclear. We reported that PQQ could protect against GM-induced ototoxicity in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells in vitro. To evaluate reactive oxygen species (ROS) production and mitochondrial function, ROS and JC-1 staining, oxygen consumption rate (OCR), and extracellular acidification rate (ECAR) measurements in living cells, mitochondrial dynamics analysis was performed. GM-mediated damage was performed by reducing the production of ROS and inhibiting mitochondria biogenesis and dynamics. PQQ ameliorated the cellular oxidative stress and recovered mitochondrial membrane potential, facilitating the recovery of mitochondrial biogenesis and dynamics. Our in vitro findings improve our understanding of the GM-induced ototoxicity with therapeutic implications for PQQ.
Subject(s)
Gentamicins , Ototoxicity , Humans , Gentamicins/metabolism , Reactive Oxygen Species/metabolism , PQQ Cofactor/pharmacology , PQQ Cofactor/therapeutic use , PQQ Cofactor/metabolism , Ototoxicity/etiology , Ototoxicity/prevention & control , Ototoxicity/metabolism , Hair Cells, Auditory/metabolism , Anti-Bacterial Agents/metabolism , ApoptosisABSTRACT
Tetracycline is a commonly used human and veterinary antibiotic that is mostly discharged into environment and thereby tetracycline-resistant bacteria are widely isolated. To combat these resistant bacteria, further understanding for tetracycline resistance mechanisms is needed. Here, GC-MS based untargeted metabolomics with biochemistry and molecular biology techniques was used to explore tetracycline resistance mechanisms of Edwardsiella tarda. Tetracycline-resistant E. tarda (LTB4-RTET ) exhibited a globally repressed metabolism against elevated proton motive force (PMF) as the most characteristic feature. The elevated PMF contributed to the resistance, which was supported by the three results: (i) viability was decreased with increasing PMF inhibitor carbonylcyanide-3-chlorophenylhydrazone; (ii) survival is related to PMF regulated by pH; (iii) LTB4-RTET were sensitive to gentamicin, an antibiotic that is dependent upon PMF to kill bacteria. Meanwhile, gentamicin-resistant E. tarda with low PMF are sensitive to tetracycline is also demonstrated. These results together indicate that the combination of tetracycline with gentamycin will effectively kill both gentamycin and tetracycline resistant bacteria. Therefore, the present study reveals a PMF-enhanced tetracycline resistance mechanism in LTB4-RTET and provides an effective approach to combat resistant bacteria.
Subject(s)
Edwardsiella tarda , Tetracycline Resistance , Humans , Edwardsiella tarda/metabolism , Gentamicins/pharmacology , Gentamicins/metabolism , Proton-Motive Force , Leukotriene B4/metabolism , Leukotriene B4/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Tetracycline/pharmacology , Tetracycline/metabolism , Bacteria/metabolismABSTRACT
INTRODUCTION: Farnesoid-X-activated receptor (FXR) is considered as an upstream controller which could influence the other key regulatory genes encoding cellular antioxidant defense system. METHODS: Thirty-five male Wistar rats (240 ± 20 g) were randomly allocated into five groups: 1) control, 2) received gentamicin (100 mg/kg/d) for three days (GM-3d), 3) seven days (GM-7d), 4) 10 days (GM-10d), and 5) 14 consecutive days (GM-14d). Biochemical measurements of BUN and serum creatinine (SCr), histological assessment of renal samples as well as molecular analysis using real-time qRT-PCR were used to investigate the pattern of changes in different levels. RESULTS: Administration of gentamicin was associated with a significant increase in the BUN and SCr until the 10th day, which then suddenly dropped at the day 14. Meantime, the maximum histological distortion was also seen on the 10th day but in a similar pattern, 14th day was associated with clear improvement. Compared to the control value, the maximum reduction in the mRNA expression of Farnesoid X-activated receptor (FXR), nuclear factor erythroid 2-related factor 2 (Nrf2) and Glutathione cysteine ligase-modulatory subunit (GCLM), occurred at the 3rd and 7th days, respectively. Compared to the control, the mRNA expression of the mentioned genes significantly increased up to day 14. Apart from the 3rd day, the mRNA expression of alpha-glutathione S-transferase (α-GST) and superoxide dismutase (SOD) showed a similar descending and ascending pattern at 7th and 10th days, respectively. CONCLUSION: The expression of FXR, as an upstream controller gene and its downstream pathways mediated by Nrf2, could play a role in gentamicin-induced nephrotoxicity but the pattern of expression was rather biphasic at the acute phase or the subacute ones. DOI: 10.52547/ijkd.7523.
Subject(s)
Drug-Related Side Effects and Adverse Reactions , Renal Insufficiency , Rats , Male , Animals , Gentamicins/toxicity , Gentamicins/metabolism , Rats, Wistar , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Kidney/pathology , RNA, Messenger/metabolism , Oxidative StressABSTRACT
Cornea transplantation is one of the most commonly performed allotransplantations worldwide. Prolonged storage of donor corneas leads to decreased endothelial cell viability, severe stromal edema, and opacification, significantly compromising the success rate of corneal transplantation. Corneal stroma, which constitutes the majority of the cornea, plays a crucial role in maintaining its shape and transparency. In this study, we conducted proteomic analysis of corneal stroma preserved in Optisol-GS medium at 4 °C for 7 or 14 days to investigate molecular changes during storage. Among 1923 identified proteins, 1634 were quantifiable and 387 were significantly regulated with longer preservation. Compared to stroma preserved for 7 days, proteins involved in ocular surface immunomodulation were largely downregulated while proteins associated with extracellular matrix reorganization and fibrosis were upregulated in those preserved for 14 days. The increase in extracellular matrix structural proteins together with upregulation of growth factor signaling implies the occurrence of stromal fibrosis, which may compromise tissue clarity and cause vision impairments. This study is the first to provide insights into how storage duration affects corneal stroma from a proteomic perspective. Our findings may contribute to future research efforts aimed at developing long-term preservation techniques and improving the quality of preserved corneas, thus maximizing their clinical application.
Subject(s)
Cryopreservation , Proteomics , Humans , Cryopreservation/methods , Cornea , Corneal Stroma/metabolism , Extracellular Matrix , Gentamicins/metabolism , Complex Mixtures/metabolismABSTRACT
The repair and functional reconstruction of large skin defects caused by burn remains an intractable clinical problem. Collagen type I (ColI) was extracted from carp scales and confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis ultraviolet adsorption spectra and automatic amino acid analyzer. Then the scaffolds containing the purified ColI, hyaluronic acid (HA) and chondroitin sulfate (CS) were constructed and examined. The results showed that the scaffold (ColI:CS:HA=9:1:1) had larger pore diameter, porosity, water absorption, degradation rate and tensile strength. gentamycin sulphate (GS) - gelatin microspheres (GMSs) were prepared by emulsion cross-linking method. The drug release study of the ColI-CS-HA-GS/GMSs scaffold with antibacterial property showed a prolonged, continuous, and sustained release of GS. The bone marrow mesenchymal stem cells (BMSCs) were extracted from rat and inoculated into the ColI-HA-CS-GS/GMSs scaffold. The results performed that the scaffold could accelerate proliferation of the BMSCs and wound healing.
Subject(s)
Mesenchymal Stem Cells , Tissue Engineering , Rats , Animals , Tissue Engineering/methods , Hyaluronic Acid/chemistry , Gelatin/chemistry , Tissue Scaffolds/chemistry , Gentamicins/pharmacology , Gentamicins/metabolism , Collagen/chemistry , Chondroitin Sulfates/chemistry , Mesenchymal Stem Cells/metabolismABSTRACT
Antibiotic overuse and misuse have promoted the emergence and spread of antibiotic-resistant bacteria. Increasing bacterial resistance to antibiotics is a major healthcare problem, necessitating elucidation of antibiotic resistance mechanisms. In this study, we explored the mechanism of gentamicin resistance by comparing the transcriptomes of antibiotic-sensitive and -resistant Escherichia coli. A total of 410 differentially expressed genes were identified, of which 233 (56.83%) were up-regulated and 177 (43.17%) were down-regulated in the resistant strain compared with the sensitive strain. Gene Ontology (GO) analysis classifies differential gene expression into three main categories: biological processes, cellular components, and molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the up-regulated genes were enriched in eight metabolic pathways, including fatty acid metabolism, which suggests that fatty acid metabolism may be involved in the development of gentamicin resistance in E. coli. This was demonstrated by measuring the acetyl-CoA carboxylase activity, plays a fundamental role in fatty acid metabolism, was increased in gentamicin-resistant E. coli. Treatment of fatty acid synthesis inhibitor, triclosan, promoted gentamicin-mediated killing efficacy to antibiotic-resistant bacteria. We also found that exogenous addition of oleic acid, which involved in fatty acid metabolism, reduced E. coli sensitivity to gentamicin. Overall, our results provide insight into the molecular mechanism of gentamicin resistance development in E. coli.
Subject(s)
Escherichia coli , Gentamicins , Gentamicins/pharmacology , Gentamicins/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Bacteria/genetics , Gene Expression Profiling , Fatty Acids/metabolism , TranscriptomeABSTRACT
Multidrug-resistant Pseudomonas aeruginosa (MDRP) is one of the most important pathogens in clinical practice. To clarify the mechanisms contributing to its emergence, we isolated MDRPs using the P. aeruginosa PAO1, the whole genome sequence of which has already been elucidated. Mutant strains resistant to carbapenems, aminoglycosides, and new quinolones, which are used to treat P. aeruginosa infections, were isolated; however, none met the criteria for MDRPs. Then, PAO1 strains were exposed to these antimicrobial agents in various orders and the appearance rate of MDRP varied depending on the order of exposure; MDRPs more frequently appeared when gentamicin was applied before ciprofloxacin, but were rarely isolated when ciprofloxacin was applied first. Exposure to ciprofloxacin followed by gentamicin increased the expression of MexCD-OprJ, an RND-type multidrug efflux pump, due to the NfxB mutation. In contrast, exposure to gentamicin followed by ciprofloxacin resulted in more mutations in DNA gyrase. These results suggest that the type of quinolone resistance mechanism is related to the frequency of MDRP and that the risk of MDRP incidence is highly dependent on the order of exposure to gentamicin and ciprofloxacin.
Subject(s)
Membrane Transport Proteins , Pseudomonas aeruginosa , Membrane Transport Proteins/metabolism , Incidence , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Ciprofloxacin/pharmacology , Ciprofloxacin/metabolism , Gentamicins/pharmacology , Gentamicins/metabolism , Microbial Sensitivity TestsABSTRACT
Background and Objectives: Gentamicin (GM) is a nephrotoxic aminoglycoside. Neutral electrolyzed saline (SES) is a compound with anti-inflammatory, antioxidant, and immunomodulatory properties. The objective of the present study was to evaluate whether kidney damage by GM can be prevented and/or reversed through the administration of SES. Materials and Methods: The study was carried out as a prospective, single-blind, five-arm, parallel-group, randomized, preclinical trial. The nephrotoxicity model was established in male BALB/c mice by administering GM at a dose of 100 mg/kg/day intraperitoneally for 30 days, concomitantly administering (+) SES or placebo (physiologic saline solution), and then administering SES for another 30 days after the initial 30 days of GM plus SES or placebo. At the end of the test, the mice were euthanized, and renal tissues were evaluated histopathologically. Results: The GM + placebo group showed significant tubular injury, interstitial fibrosis, and increased interstitial infiltrate of inflammatory cells compared with the group without GM. Tubular injury and interstitial fibrosis were lower in the groups that received concomitant GM + SES compared with the GM + placebo group. SES administration for 30 days after the GM administration periods (GM + placebo and GM + SES for 30 days) did not reduce nephrotoxicity. Conclusions: Intraperitoneal administration of SES prevents gentamicin-induced histologic nephrotoxicity when administered concomitantly, but it cannot reverse the damage when administered later.
Subject(s)
Gentamicins , Kidney , Animals , Male , Mice , Rats , Disease Models, Animal , Fibrosis , Gentamicins/metabolism , Gentamicins/pharmacology , Kidney/pathology , Oxidative Stress , Prospective Studies , Rats, Wistar , Saline Solution/pharmacology , Single-Blind MethodABSTRACT
The emergence of antibiotic resistance greatly increases the difficulty of treating bacterial infections. In order to develop effective treatments, the underlying mechanisms of antibiotic resistance must be understood. In this study, Staphylococcus aureus ATCC6538 strain was passaged in medium with and without gentamicin and obtained lab-evolved gentamicin-resistant S. aureus (RGEN) and gentamicin-sensitive S. aureus (SGEN) strains, respectively. Data-Independent Acquisition (DIA)-based proteomics approach was applied to compare the two strains. A total of 1426 proteins were identified, of which 462 were significantly different: 126 were upregulated and 336 were downregulated in RGEN compared to SGEN. Further analysis found that reduced protein biosynthesis was a characteristic feature in RGEN, related to metabolic suppression. The most differentially expressed proteins were involved in metabolic pathways. In RGEN, central carbon metabolism was dysregulated and energy metabolism decreased. After verification, it was found that the levels of NADH, ATP, and reactive oxygen species (ROS) decreased, and superoxide dismutase and catalase activities increased. These findings suggest that inhibition of central carbon and energy metabolic pathways may play an important role in the resistance of S. aureus to gentamicin, and that gentamicin resistance is associated with oxidative stress. Significance: The overuse and misuse of antibiotics have led to bacterial antibiotic resistance, which is a serious threat to human health. Understanding the mechanisms of antibiotic resistance will help better control these antibiotic-resistant pathogens in the future. The present study characterized the differential proteome of gentamicin-resistant Staphylococcus aureus using the most advanced DIA-based proteomics technology. Many of the differential expressed proteins were related to metabolism, specifically, reduced central carbon and energy metabolism. Lower levels of NADH, ROS, and ATP were detected as a consequence of the reduced metabolism. These results reveal that downregulation of protein expression affecting central carbon and energy metabolisms may play an important role in the resistance of S. aureus to gentamicin.
Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Humans , Staphylococcus aureus/metabolism , Gentamicins/pharmacology , Gentamicins/metabolism , Methicillin-Resistant Staphylococcus aureus/metabolism , Proteomics/methods , Carbon/metabolism , NAD/metabolism , Reactive Oxygen Species/metabolism , Anti-Bacterial Agents/pharmacology , Staphylococcal Infections/microbiology , Energy Metabolism , Drug Resistance, Bacterial , Adenosine Triphosphate/metabolism , Microbial Sensitivity TestsABSTRACT
Mitochondrial dysfunction is a fundamental mechanism leading to drug nephrotoxicity, such as gentamicin-induced nephrotoxicity. Mitochondrial therapy (mitotherapy) or exogenous mitochondria transplantation is a method that can be used to replace dysfunctional mitochondria with healthy mitochondria. This method can help in the treatment of diseases related to mitochondria. In this research, we studied the transplantation effect of freshly isolated mitochondria on the toxicity induced by gentamicin on renal proximal tubular cells (RPTCs). Furthermore, possible gender-related effects on supplying exogenous rat kidney mitochondria on gentamicin-induced RPTCs were investigated. At first, the normality and proper functioning of fresh mitochondria were assessed by measuring mitochondrial succinate dehydrogenase activity (SDH) and changes in mitochondrial membrane potential (MMP). Then, the protective effects of mitochondrial transplantation against gentamicin-induced mitochondrial toxicity were evaluated through parameters including lactate dehydrogenase (LDH) leakiness, reactive oxygen species (ROS) production, lipid peroxidation (LPO) content, reduced glutathione (GSH) level, extracellular oxidized glutathione (GSSG) level, ATP level, MMP collapse, and caspase-3 activity. According to the statistical analysis, transplanting the healthy mitochondria decreased the cytotoxicity, ROS production, MMP collapse, LPO content, GSSG levels, and caspase-3 activity caused by gentamicin in RPTCs. Also, it has caused an increase in the level of ATP and GSH in the RPTCs. Furthermore, higher preventive effects were observed for the female group. According to the current study, mitochondrial transplantation is a potent therapeutic method in xenobiotic-caused nephrotoxicity.
Subject(s)
Gentamicins , Oxidative Stress , Rats , Female , Animals , Reactive Oxygen Species/metabolism , Gentamicins/metabolism , Gentamicins/pharmacology , Glutathione Disulfide/metabolism , Glutathione Disulfide/pharmacology , Caspase 3/metabolism , Kidney/metabolism , Mitochondria , Glutathione/metabolism , Lipid Peroxidation , Adenosine Triphosphate/metabolism , Membrane Potential, MitochondrialABSTRACT
Many signaling enzymes have multiple isozymes that are localized discretely at varying molecular levels in different compartments of cells where they play specific roles. In this study, among the various isozymes of phospholipase C (PLC) and diacylglycerol kinase (DGK), which work sequentially in the phosphoinositide cycle, both PLCß3 and DGKι were found in renal brush-border microvilli, but found to replace each other along the proximal tubules: PLCß3 in the proximal straight tubules (PST) of the outer stripe of the outer medulla (OSOM) and the medullary ray (MR), and DGKι in the proximal convoluted tubules (PCT) in the cortex and partially in the PST of the MR. Following daily injection of gentamicin for 1 week, the expression of PLCß3 and DGKι was transiently enhanced, as demonstrated by western blot, and the increases were found to most likely occur in their original sites, that is, in the brush borders of the PST for PLCß3 and in the PCT for DGKι. These findings showing differences in expression along the tubules suggest that the exertion of reabsorption and secretion through various ion channels and transporters in the microvillus membranes and the maintenance of microvillus turnover are regulated by a PLC-mediated signal with the balance shifted toward relative augmentation of the DAG function in the PST, and by a DGK-mediated signal with the balance shifted to relative augmentation of the phosphatidic acid function in the PCT. Our results also suggest the possibility that these isozymes are potential diagnostic signs for the early detection of acute kidney injury caused by gentamicin.
Subject(s)
Diacylglycerol Kinase , Phospholipases , Rats , Animals , Diacylglycerol Kinase/metabolism , Phospholipases/metabolism , Gentamicins/metabolism , Isoenzymes/metabolism , Kidney/metabolism , Kidney Tubules, ProximalABSTRACT
This study aimed to establish the relationship between two endoplasmic reticulum (ER) stress proteins, glucose-regulated protein 78 (GRP78/BiP) and PKR-like endoplasmic reticulum kinase (PERK), and oxidative stress markers in cisplatin (CIS)-induced and gentamicin (GEN)-induced nephrotoxicity.The study consisted of five groups: control (saline solution only), CIS D2 (2.5 mg/kg for 2 days), CIS D7 (2.5 mg/kg for 7 days), GEN D2 (160 mg/kg for 2 days), and GEN D7 (160 mg/kg for 7 days). All rats were sacrificed 24 h after the last injection for standard clinical chemistry, and ultrastructural and histological evaluation of the kidney.CIS and GEN increased blood urea nitrogen (BUN) and serum creatinine (Cr) levels, as well as total oxidant status (TOS), while decreasing total antioxidant status (TAS) level in CIS D7 and GEN D7 groups. Histopathological and ultrastructural findings were also consistent with renal tubular damage. In addition, expression of markers of renal inflammation (tumor necrosis factor-α (TNF-α) and interleukin 1ß (IL-1ß)) and ER stress markers (GRP78 and PERK) was significantly increased in the kidney tissue of rats treated with CIS and GEN for 7 days.These findings suggest that CIS and GEN administration for 7 days aggravates nephrotoxicity through the enhancement of oxidative stress, inflammation, and ER stress-related markers. As a result, the recommended course of action is to utilize CIS and GEN as an immediate but brief induction therapy, stopping after 3 days and switching to other drugs instead.
Subject(s)
Cisplatin , Endoplasmic Reticulum Chaperone BiP , Animals , Rats , Cisplatin/toxicity , Endoplasmic Reticulum , Gentamicins/toxicity , Gentamicins/metabolism , Inflammation/drug therapy , Kidney , Oxidative Stress , Endoplasmic Reticulum StressABSTRACT
This study was designed, for the first time, to examine the possible nephroprotective effects of exogenous glutathione (EGSH) (100 mg/kg, intraperitoneally) on gentamicin-induced acute kidney injury (GM-induced AKI). EGSH reduced renal histopathological changes, inflammatory cell infiltration, and improved renal dysfunction in rats with AKI. EGSH ameliorated GM-induced renal oxidative stress by promoting the renal activities of catalase, glutathione peroxidase, and superoxide dismutase and diminishing renal malondialdehyde and serum nitric oxide levels. Interestingly, EGSH inhibited intrinsic apoptosis by downregulating Bax and caspase-3 and upregulating Bcl2 in the kidney of rats with AKI. EGSH decreased GM-induced inflammatory response as reflected by a remarkable decrease in the protein expressions of NF-κB-p65, IL-6, TNF-α, and iNOS and a considerable diminish in myeloperoxidase activity. Finally, EGSH markedly declined proliferative cell nuclear antigen (PCNA) protein expression in the animals with AKI. In summary, EGSH alleviated AKI in rats intoxicated with GM, partially by inhibiting oxidative stress, NF-κB pathway, and intrinsic apoptosis and regulating PCNA.
Subject(s)
Acute Kidney Injury , NF-kappa B , Rats , Animals , NF-kappa B/metabolism , NF-kappa B/pharmacology , Gentamicins/toxicity , Gentamicins/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Proliferating Cell Nuclear Antigen/pharmacology , Acute Kidney Injury/chemically induced , Acute Kidney Injury/prevention & control , Acute Kidney Injury/metabolism , Oxidative Stress , Kidney , Glutathione/metabolism , ApoptosisABSTRACT
Gentamicin (GM) is an effective antibiotic administered to treat acute Gram-negative infections. Nevertheless, its clinical application is limited due to nephrotoxicity. Therefore, our research aimed to investigate the potential renoprotective impact of rebamipide (RBM), a gastroprotective drug, on GM-induced kidney damage in rats, as well as putative nephroprotective pathways. RBM was orally administered (100 mg/kg/d for 14 d) commencing 7 d before the administration of GM (100 mg/kg/d, intraperitoneally). Nephrotoxicity was elucidated, and the silent information regulator 1 (SIRT1) and ß-catenin/cyclin D1 pathways were assessed. GM induced a significant elevation in the serum levels of creatinine, blood urea nitrogen (BUN), and kidney injury molecule-1 (KIM-1), as well as the relative kidney index. In addition, GM increased lipid peroxidation and lowered total antioxidant capacity (TAC) level and superoxide dismutase (SOD) activity. GM administration also demonstrated a significant amplification in tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), nuclear factor-κappa B p65 (NF-κB p65), p38 mitogen-activated protein kinase (p38 MAPK), and caspase-3 kidney levels, as well as B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 ratio. Notably, RBM treatment amended all these changes induced by GM. Furthermore, the potential role of SIRT1 and ß-catenin-dependent signaling pathways in GM-induced renal injury was assessed. Our findings showed that GM-treated rats demonstrated a substantial decrease in SIRT1, nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) along with an increase in ß-catenin, forkhead box O-3a (FOXO-3a), and cyclin D1 protein expressions. RMB treatment markedly attenuated the deterioration caused by GM on these pathways. Additionally, RBM alleviated the GM-induced deleterious kidney tissue histopathology. In conclusion, our findings have verified that RBM can halt GM-induced renal injury by partly modulating SIRT1 and ß-catenin pathways.
Subject(s)
Gentamicins , Sirtuin 1 , Rats , Animals , Gentamicins/toxicity , Gentamicins/metabolism , Sirtuin 1/metabolism , Sirtuin 1/pharmacology , Cyclin D1/metabolism , beta Catenin/metabolism , beta Catenin/pharmacology , Kidney , Proto-Oncogene Proteins c-bcl-2/metabolism , Oxidative Stress , NF-kappa B/metabolism , NF-kappa B/pharmacology , NF-E2-Related Factor 2/metabolismABSTRACT
Aminoglycoside antibiotics such as gentamicin are used frequently to treat bacterial infections in humans. Excessive consumption of these antibiotics lead to renal dysfunction. One of the factors contributing to renal dysfunction is oxidative damage, which causes apoptosis. Hence, this study investigates the effect of the antioxidant compound deacetyl epoxyazadiradione (DEA) in reducing cell death induced by gentamicin treatment in kidney cells (Madin-Darby canine kidney cells). The antioxidant experiments showed that reactive oxygen species level is decreased up to 27.06 ± 0.18% in 150 µM of DEA treatment. At this concentration, the activity of antioxidant enzymes such as superoxide dismutase increased from 0.4 ± 0.04 to 1.46 ± 0.05 µmol/min/L and catalase increased from 7.48 ± 0.39 to 17.6 ± 0.74 U/mg. The relative folds of gene expression of mitochondrial enzymes such as GST, GPx and GR restored from 0.596 ± 0.019, 0.521 ± 0.013 and 0.775 ± 0.014 to 0.866 ± 0.013, 0.669 ± 0.015 and 0.8615 ± 0.028, respectively. Consequently, the percentage of cell viability increases upto 91.8 ± 2.01 from 61.93 ± 1.63 with much less fragmentation in genomic DNA. Additionally, molecular docking results showed that DEA could bind to Bax, Bcl- 2, Caspase- 3 and Caspase- 9 proteins. These results indicate that DEA could reduce cell apoptosis by reducing oxidative stress due to antibiotics and interrupting the apoptotic signal pathway in kidney cells.
Subject(s)
Antioxidants , Kidney Diseases , Humans , Animals , Dogs , Antioxidants/pharmacology , Molecular Docking Simulation , Kidney/metabolism , Apoptosis , Oxidative Stress , Anti-Bacterial Agents/metabolism , Reactive Oxygen Species/metabolism , Gentamicins/metabolism , Gentamicins/pharmacology , Kidney Diseases/metabolismABSTRACT
Persister cell (PC) is dormant, tolerant to antibiotics, and a transient reversible phenotype. These phenotypes are observed in P. aeruginosa and cause bacterial chronic infection as well as recurrence of biofilm-mediated infection. PC formation requires stringent response and toxin-antitoxin (TA) modules. This study shows the P. aeruginosa PC formation in planktonic and biofilm stages on ceftazidime, gentamicin, and ciprofloxacin treatments. The PC formation was studied using persister assay, flow cytometry using Redox Sensor Green, fluorescence as well as Confocal Laser Scanning Microscopy, and gene expression of stringent response and TA genes. In the planktonic stage, ceftazidime showed a high survival fraction, high redox activity, and elongation of cells was observed followed by ciprofloxacin and gentamicin treatment having redox activity and rod-shaped cells. The gene expression of stringent response and TA genes were upregulated on gentamicin followed by ceftazidime treatment and varied among the isolates. In the biofilm stage, gentamicin and ciprofloxacin showed the biphasic killing pattern, redox activity, gene expression level of stringent response and TA varied across the isolates. Ceftazidime treatment showed higher persister cells in planktonic growth while all three antibiotics were able to induce persister cell formation in the biofilm stage.
Subject(s)
Antitoxins , Bacterial Infections , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antitoxins/metabolism , Biofilms , Ceftazidime/pharmacology , Ciprofloxacin/metabolism , Ciprofloxacin/pharmacology , Gentamicins/metabolism , Gentamicins/pharmacology , Humans , Microbial Sensitivity Tests , Plankton , Pseudomonas aeruginosaABSTRACT
BACKGROUND: Increasing studies have reported that gentamicin (GNT) plays an essential role in sepsis; however, its underlying mechanism is still unclear. In this study, we investigated the mechanism of GNT in sepsis. RESULTS: We observed that GNT enhanced survival and alleviated inflammatory injuries of the lungs, liver, kidneys, and intestines in mice with sepsis. Furthermore, regulatory T cells (Tregs) showed enhanced inhibitory function, and pro-inflammatory cytokines IL-1ß, TNF-α, and IL-2 and anti-inflammatory cytokine IL-10 showed decreased and increased peritoneal fluid levels, respectively, after treatment with GNT. GNT showed enhanced phosphorylation of signal transducer and activator of transcription 5 (p-STAT5) in Tregs in vivo and in vitro. The STAT5 inhibitor restrained the increased functional changes of Tregs and reduced inflammatory responses induced by GNT in vitro. Moreover, the STAT5 inhibitor reversed GNT-mediated impacts on survival and inflammation, and the percentage, apoptosis, and phenotypic and functional changes of Tregs in neonatal sepsis. CONCLUSIONS: Our study revealed that GNT regulates the function of Tregs via the STAT5 signaling pathway, alleviating inflammatory injuries, and provides novel evidence in the treatment of neonatal sepsis.