Tip60 might be a candidate for the acetylation of hepatic carbonic anhydrase I and III in mice

Background Carbonic anhydrases (CAs) play a significant role in maintaining pH balance by catalyzing the conversion of carbon dioxide to bicarbonate. The regulation of pH is critical for all living organisms. Although there are many studies in the literature on the biochemical, functional, and structural features of CAs, there is not sufficient information about the epigenetic regulation of CAs. Methods and results The lysine acetyltransferase TIP60 (60 kDa Tat-interactive protein) was knocked out specifically in mouse liver using the Cre/loxP system, and knockout rate was shown as 83–88% by Southern blot analysis. The impact of Tip60 on the expression of Ca1, Ca3, and Ca7 was investigated at six Zeitgeber time (ZT) points in the control and liverspecific Tip60 knockout mice (mutant) groups by real-time PCR. In the control group, while Ca1 showed the highest expression at ZT8 and ZT12, the lowest expression profile was observed at ZT0 and ZT20. Hepatic Ca1 displayed robust circadian expression. However, hepatic Ca3 exhibited almost the same level of expression at all ZT points. The highest expression of Ca7 was observed at ZT12, and the lowest expression was determined at ZT4. Furthermore, hepatic Ca7 also showed robust circadian expression. The expression of Ca1 and Ca3 significantly decreased in mutant mice at all time periods, but the expression of Ca7 used as a negative control was not affected. Conclusions It was suggested for the first time that Tip60 might be considered a candidate protein in the regulation of the Ca1 and Ca3 genes, possibly by acetylation

Depletion of Tip60/Kat5 affects the hepatic antioxidant system in mice

Tat-interactive protein 60 kDa (TIP60, also known as lysine acetyltransferase 5 [KAT5]) is a member of the MYST protein family with histone acetyltransferase activity. Recent studies have reported that TIP60 has multiple functions in many signal transduction mechanisms, especially p53-mediated apoptosis. Although the activation of apoptosis signaling pathways requires the presence of cellular reactive oxygen species (ROS) at a certain level, an imbalance between the production and consumption of ROS in cells results in oxidative stress (OS). In this study, we investigated for the first time how the absence of the Tip60 gene in the liver affects gene expression, enzyme activity, and protein expression of the hepatic antioxidant members localized in the cytoplasm, including superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST). First, we successfully generated liver-specific Tip60 knockout mice (mutants) using Cre/LoxP recombination. The reduced glutathione level and nicotinamide adenine dinucleotide phosphate oxidase 4 (Nox4) expression, a marker of OS, increased significantly in the Tip60 mutant liver. Gene expression, activity, and protein expression of the enzymatic antioxidant system, including SOD, CAT, GR, GPx, and GST were investigated in mutants and control groups. Despite a significant correlation between the gene, enzyme activity, and protein content for CAT and GR, this was not true for SOD and GPx. The overall results suggest that TIP60 acts on the hepatic antioxidant system both at the gene and protein levels, but the actual effect of the deletion of Tip60 is observed at the protein level, especially for SOD and GPx.Ataturk University Scientific Research Projects Coordination Commission [PRJ2010/279, PRJ2013/293]Ataturk University Scientific Research Projects Coordination Commission, Grant/Award Numbers: PRJ2010/279, PRJ2013/29

The effects of amoxicillin, cefazolin, and gentamicin antibiotics on the antioxidant system in mouse heart tissues

CIFTCI, MEHMET/0000-0002-1748-3729; KOCPINAR, ENVER FEHIM/0000-0002-6031-4664; Budak, Harun/0000-0002-7371-8959; Sisecioglu, Melda/0000-0002-1127-0570WOS:000560347900005PubMed: 31721686Background: Free radicals lead to destruction in various organs of the organism. The improper use of antibiotics increases the formation of free radicals and causes oxidative stress. Objective: In this study, it was aimed to determine the effects of gentamicin, amoxicillin, and cefazolin antibiotics on the mouse heart. Methods: 20 male mice were divided into 4 groups (1st control, 2nd amoxicillin, 3rd cefazolin, and 4th gentamicin groups). The mice in the experimental groups were administered antibiotics intraperitoneally at a dose of 100 mg / kg for 6 days. The control group received normal saline in the same way. The gene expression levels and enzyme activities of SOD, CAT, GPx, GR, GST, and G6PD antioxidant enzymes were investigated. Results: GSH levels decreased in both the amoxicillin and cefazolin groups, while GR, CAT, and SOD enzyme activities increased. In the amoxicillin group, Gr, Gst, Cat, and Sod gene expression levels increased. Conclusion: As a result, it was concluded that amoxicillin and cefazolin caused oxidative stress in the heart, however, gentamicin did not cause any effects.Scientific Research Project of Ataturk University of TurkeyAtaturk University [PRJ2013/296]This work was supported by a grant from the Scientific Research Project of Ataturk University of Turkey [Grant Number: PRJ2013/296]

Diffractaic acid exhibits thioredoxin reductase 1 inhibition in lung cancer A549 cells

Lung cancer is the leading cause of cancer-related deaths all over the world. Therefore, it has gained importance in the development of new chemotherapeutic strategies to identify anticancer agents with low side effects, reliable, high anticancer potential, and specific to lung cancer cells. Thioredoxin reductase 1 (TrxR1) is an important therapeutic target for lung cancer treatment because of its overexpression in tumor cells. Here, we aimed to examine the anticancer effect of diffractaic acid, a lichen secondary metabolite, in A549 cells by comparing it with the commercial chemotherapeutic drug carboplatin and also to investigate whether the anticancer effect of diffractaic acid occurs via TrxR1-targeting. The IC50 value of diffractaic acid on A549 cells was determined as 46.37 μg/mL at 48 h, and diffractaic acid had stronger cytotoxicity than carboplatin in A549 cells. qPCR results revealed that diffractaic acid promoted the intrinsic apoptotic pathway through the upregulation of the BAX/BCL2 ratio and P53 gene in A549 cells, which is consistent with the flow cytometry results. Furthermore, migration analysis results indicated that diffractaic acid impressively suppressed the migration of A549 cells. While the enzymatic activity of TrxR1 was inhibited by diffractaic acid in A549 cells, no changes were seen in the quantitative expression levels of gene and protein. These findings provide fundamental data on the anticancer effect of diffractaic acid on A549 cells targeting TrxR1 activity, suggesting that it could be considered a chemotherapeutic agent for lung cancer therapy

A comparison of the inhibitory effects of anti-cancer drugs on thioredoxin reductase and glutathione S-transferase in rat liver

WOS: 000458732100013PubMed: 30198440Background: While Thioredoxin Reductase (TrxR) plays an important role in regulation of the intracellular redox balance and various signalling pathways, Glutathione S-Transferase (GSTs) enzymes belong to the detoxification family that catalyse the conjugation of glutathione with various endogenous and xenobiotic electrophiles. Since TrxR and GSTs are overexpressed in many cancer cells, they have been identified as potential targets to develop chemotherapeutic strategies. Method: The mitochondrial TrxR (TrxR2) enzyme and the cytosolic CYST enzyme was purified from rat liver via affinity chromatography. After the purification, the in vitro inhibition effects of some anticancer drugs (cisplatin, calcium folinate, carboplatin, epirubicin hydrochloride, doxorubicin hydrochloride, paclitaxel, etoposide, fluorouracil, and methotrexate) were investigated on both enzymes. Since only methotrexate inhibits both enzymes among all the anticancer drugs, a molecular docking study was performed to determine the binding site and the binding affinity of methotrexate to the enzymes. Results: Firstly, TrxR2 and GST were found to have a specific activity of 0.436, 1765 EU/mg proteins with a yield of 39.20%, 31.28% and 207.6, 3516.6 of purification fold, respectively. While TrxR2 was strongly inhibited by all of the anticancer drugs, GST was not inhibited by any of the anticancer drugs except methotrexate. Conclusion: Both enzymes were inhibited by only methotrexate in rat liver, and methotrexate was well placed in the active sites of both proteins. Therefore, it may be argued that methotrexate may be a more effective anticancer drug than all other drugs used in this study against the multi drug resistance that will occur during chemotherapy.Ataturk University Scientific Research Projects Coordination Commission (ATAUNIBAP) [PRJ2015/97, PRJ2015/357]This work was financially supported by Ataturk University Scientific Research Projects Coordination Commission (ATAUNIBAP) with project number PRJ2015/97 and PRJ2015/357. The author(s) have no potential conflict of interest with respect to the research, authorship, and/or publication of this article. Conceived and designed the experiments: Harun Budak (group leader) and Ilknur Ozgencli. Performed the experiments: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, Ugur Guller, Mehmet Ciftci, and Omer I. Kufrevioglu. Analysed the data: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. Contributed reagents/materials/analysis tools: Harun Budak. Wrote the paper: Harun Budak, Ilknur Ozgencli, Deryanur Kilic, and Ugur Guller. All authors read and approved the final manuscript