Glutathione-S-Transferase and Thiol Stress in patients with acute renal failure

Introduction: Tubular damage is common finding in acute renal failure (ARF). Various etiologies have been put forth to explain the tubular damage in ARF, one important mechanism among them is oxidative damage to renal tubules. Several biomolecules including low-molecular weight peptides and enzymes in urine have been proposed as early markers of renal failure. Current study has been undertaken to study the thiol stress and glutathione-S-transferase (GST) levels in ARF patients. Method: 58 ARF patients and 55 healthy controls were selected based on inclusion and exclusion criteria. Serum thiols, GST, malanoldehyde (MDA) and urine thiols were determined by spectrophotometer based methods. Results: Serum thiols and urine thiols were significantly decreased (p<0.0001), and serum GST and MDA levels were significantly increased (p<0.0001) in ARF patients compared to healthy controls. Serum GST and MDA correlated positively in ARF cases (r2 = 0.6938, p<0.0001). Conclusion: There is significant thiol stress and increased lipid peroxidation in ARF patients which leads to tubular cell membrane damage and release of GST into blood stream and into urine. This may be possible mechanism for the increased presence of GST in urine (enzymuria) found in other studie

Glutathione S-Transferase activity and total thiol status in chronic alcohol abusers before and 30 days after alcohol abstinence

Background: Glutathione S Transferase (GST) has been involved in detoxification process in the liver and its activity has been shown to be increased in alcohol abusers. In the current work we measured the GST activity, total thiol status, AST, ALT, and direct bilirubin in chronic alcohol abusers before and 30 days after alcohol abstinence and lifestyle modification. Methods: Serum and urine GST activity and total thiol status were determined using spectrophotometric methods and serum transaminases were determined using clinical chemistry analyzer. Results: We found,significant increase in serum and urine GST (p<0.001), AST (p<0.001), ALT (p<0.001), and decrease in total thiol status (p<0.001) in chronic alcohol abusers. GST activity significantly decreased (p<0.001) and total thiol status were improved significantly (p<0.001) 30 days after alcohol abstinence and lifestyle modification. Conclusion: This study provides preliminary data to suggest the role of GST as prognostic indicator of alcohol abstinence with possible trend towards an improvement in liver function

Comparison of MAPK specificity across the ETS transcription factor family identifies a high-affinity ERK interaction required for ERG function in prostate cells

Background The RAS/MAPK signaling pathway can regulate gene expression by phosphorylating and altering the function of some, but not all, ETS transcription factors. ETS family transcription factors bind similar DNA sequences and can compete for genomic binding sites. However, MAPK regulation varies across the ETS family. Therefore, changing the ETS factor bound to a cis-regulatory element can alter MAPK regulation of gene expression. To understand RAS/MAPK regulated gene expression programs, comprehensive knowledge of the ETS family members that are MAPK targets and relative MAPK targeting efficiency across the family is needed. Results An in vitro kinase assay was used to rank-order 27 human ETS family transcription factors based on phosphorylation by ERK2, JNK1, and p38α. Many novel MAPK targets and specificities were identified within the ETS family, including the identification of the prostate cancer oncoprotein ERG as a specific target of ERK2. ERK2 phosphorylation of ERG S215 required a DEF docking domain and was necessary for ERG to activate transcription of cell migration genes and promote prostate cell migration. The ability of ERK2 to bind ERG with higher affinity than ETS1 provided a potential molecular explanation for why ERG overexpression drives migration of prostate cells with low levels of RAS/ERK signaling, while ETS1 has a similar function only when RAS/ERK signaling is high. Conclusions The rank ordering of ETS transcription factors as MAPK targets provides an important resource for understanding ETS proteins as mediators of MAPK signaling. This is emphasized by the difference in rank order of ERG and ETS1, which allows these factors to have distinct roles based on the level of RAS/ERK signaling present in the cell

A Comparative Study Between Alcoholics of Koraga Community, Alcoholics of General Population and Healthy Controls for Antioxidant Markers and Liver Function Parameters

Objectives: It is well established that long-term alcohol consumption leads to liver cirrhosis and other related disorders. Sufficient work has been done on biochemical markers of liver damage and antioxidant status of chronic alcoholics in general population. In the current study chronic alcoholics from a community called Koraga are analysed for the same parameters in a view to assess the extent of liver damage as compared to healthy controls and other alcoholics. Methods: Serum and urine samples from Koraga alcoholics (n=28), general alcoholics (n=30) and healthy controls (n=31) were analysed for liver function parameters and antioxidant markers. Liver function parameters were determined by automated analyzer. Markers of antioxidant status were estimated spectrophotometrically. The data was analysed using SPSS version 16.0. Results: There was significant increase in serum AST, serum ALT, serum GST and urine GST in both general and Koraga alcoholics when compared to healthy controls (p<0.0001). Serum ALT, serum GST and urine GST activity was significantly higher in general alcoholics when compared to Koraga alcoholics (p<0.001). Serum and urine total thiol levels were significantly lower in general alcoholics when compared to healthy controls and Koraga alcoholics (p<0.0001). We have observed no difference in total thiols level between healthy controls and Koraga alcoholics, in fact, there was significant increase in urine total thiols level in Koraga alcoholics compared to healthy controls (p<0.001). On Pearson’s correlation serum AST, serum ALT correlated positively with serum and urine GST (p<0.0001) and negatively with serum total thiols (p<0.0001). Serum GST correlated negatively with serum total thiols (p<0.0001). Conclusion: Results of our study possibly indicate that the extent of alcohol induced liver damage in Koraga subjects is comparatively lower than general alcoholics, even though the alcohol consumption is found to be higher in them. There may be some mechanism that is rendering them resistant to alcoholic liver damage which needs to be explored through further studies at molecular level

Evidence-based assessment of antiosteoporotic activity of petroleum-ether extract of Cissus quadrangularis Linn. on ovariectomy-induced osteoporosis

The increasing incidence of postmenopausal osteoporosis and its related fractures have become global health issues in the recent days. Postmenopausal osteoporosis is the most frequent metabolic bone disease; it is characterized by a rapid loss of mineralized bone tissue. Hormone replacement therapy has proven efficacious in preventing bone loss but not desirable to many women due to its side-effects. Therefore we are in need to search the natural compounds for a treatment of postmenopausal symptoms in women with no toxic effects. In the present study, we have evaluated the effect of petroleum-ether extract of Cissus quadrangularis Linn. (CQ), a plant used in folk medicine, on an osteoporotic rat model developed by ovariectomy. In this experiment, healthy female Wistar rats were divided into four groups of six animals each. Group 1 was sham operated. All the remaining groups were ovariectomized. Group 2 was fed with an equivolume of saline and served as ovariectomized control (OVX). Groups 3 and 4 were orally treated with raloxifene (5.4 mg/kg) and petroleum-ether extract of CQ (500 mg/kg), respectively, for 3 months. The findings were assessed on the basis of animal weight, morphology of femur, and histochemical localization of alkaline phosphatase (ALP) (an osteoblastic marker) and tartrate-resistant acid phosphatase (TRAP) (an osteoclastic marker) in upper end of femur. The study revealed for the first time that the petroleum-ether extract of CQ reduced bone loss, as evidenced by the weight gain in femur, and also reduced the osteoclastic activity there by facilitating bone formation when compared to the OVX group. The osteoclastic activity was confirmed by TRAP staining, and the bone formation was assessed by ALP staining in the femur sections. The color intensity of TRAP and ALP enzymes from the images were evaluated by image analysis software developed locally. The effect of CQ was found to be effective on both enzymes, and it might be a potential candidate for prevention and treatment of postmenopausal osteoporosis. The biological activity of CQ on bone may be attributed to the phytogenic steroids present in it

Targeting the ERG oncogene with splice-switching oligonucleotides as a novel therapeutic strategy in prostate cancer

This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordBackground The ERG oncogene, a member of the ETS family of transcription factor encoding genes, is a genetic driver of prostate cancer. It is activated through a fusion with the androgen-responsive TMPRSS2 promoter in 50% of cases. There is therefore significant interest in developing novel therapeutic agents that target ERG. We have taken an antisense approach and designed morpholino-based oligonucleotides that target ERG by inducing skipping of its constitutive exon 4. Methods We designed antisense morpholino oligonucleotides (splice-switching oligonucleotides, SSOs) that target both the 5′ and 3′ splice sites of ERG’s exon 4. We tested their efficacy in terms of inducing exon 4 skipping in two ERG-positive cell lines, VCaP prostate cancer cells and MG63 osteosarcoma cells. We measured their effect on cell proliferation, migration and apoptosis. We also tested their effect on xenograft tumour growth in mice and on ERG protein expression in a human prostate cancer radical prostatectomy sample ex vivo. Results In VCaP cells, both SSOs were effective at inducing exon 4 skipping, which resulted in a reduction of overall ERG protein levels up to 96 h following a single transfection. SSO-induced ERG reduction decreased cell proliferation, cell migration and significantly increased apoptosis. We observed a concomitant reduction in protein levels for cyclin D1, c-Myc and the Wnt signalling pathway member β-catenin as well as a marker of activated Wnt signalling, p-LRP6. We tested the 3′ splice site SSO in MG63 xenografts in mice and observed a reduction in tumour growth. We also demonstrated that the 3′ splice site SSO caused a reduction in ERG expression in a patient-derived prostate tumour tissue cultured ex vivo. Conclusions We have successfully designed and tested morpholino-based SSOs that cause a marked reduction in ERG expression, resulting in decreased cell proliferation, a reduced migratory phenotype and increased apoptosis. Our initial tests on mouse xenografts and a human prostate cancer radical prostatectomy specimen indicate that SSOs can be effective for oncogene targeting in vivo. As such, this study encourages further in vivo therapeutic studies using SSOs targeting the ERG oncogene.Prostate Cancer U

An Interaction with Ewing’s Sarcoma Breakpoint Protein EWS Defines a Specific Oncogenic Mechanism of ETS Factors Rearranged in Prostate Cancer

Summary: More than 50% of prostate tumors have a chromosomal rearrangement resulting in aberrant expression of an oncogenic ETS family transcription factor. However, mechanisms that differentiate the function of oncogenic ETS factors expressed in prostate tumors from non-oncogenic ETS factors expressed in normal prostate are unknown. Here, we find that four oncogenic ETS (ERG, ETV1, ETV4, and ETV5), and no other ETS, interact with the Ewing’s sarcoma breakpoint protein, EWS. This EWS interaction was necessary and sufficient for oncogenic ETS functions including gene activation, cell migration, clonogenic survival, and transformation. Significantly, the EWS interacting region of ERG has no homology with that of ETV1, ETV4, and ETV5. Therefore, this finding may explain how divergent ETS factors have a common oncogenic function. Strikingly, EWS is fused to various ETS factors by the chromosome translocations that cause Ewing’s sarcoma. Therefore, these findings link oncogenic ETS function in both prostate cancer and Ewing’s sarcoma. : A subset of ETS transcription factors is oncogenic in prostate. Kedage et al. show that oncogenic ETS, but not other ETS, interact with EWS, and this interaction is necessary for oncogenic functions. Because EWS is fused to ETS factors in Ewing’s sarcoma, this finding links the mechanisms of these diseases. Keywords: prostate cancer, ETS, EWS, Ewing’s sarcoma, ER

A Comparative Study Between Alcoholics of Koraga Community, Alcoholics of General Population and Healthy Controls for Antioxidant Markers and Liver Function Parameters

Objectives: It is well established that long-term alcohol consumption leads to liver cirrhosis and other related disorders. Sufficient work has been done on biochemical markers of liver damage and antioxidant status of chronic alcoholics in general population. In the current study chronic alcoholics from a community called Koraga are analysed for the same parameters in a view to assess the extent of liver damage as compared to healthy controls and other alcoholics. Methods: Serum and urine samples from Koraga alcoholics (n=28), general alcoholics (n=30) and healthy controls (n=31) were analysed for liver function parameters and antioxidant markers. Liver function parameters were determined by automated analyzer. Markers of antioxidant status were estimated spectrophotometrically. The data was analysed using SPSS version 16.0. Results: There was significant increase in serum AST, serum ALT, serum GST and urine GST in both general and Koraga alcoholics when compared to healthy controls (p<0.0001). Serum ALT, serum GST and urine GST activity was significantly higher in general alcoholics when compared to Koraga alcoholics (p<0.001). Serum and urine total thiol levels were significantly lower in general alcoholics when compared to healthy controls and Koraga alcoholics (p<0.0001). We have observed no difference in total thiols level between healthy controls and Koraga alcoholics, in fact, there was significant increase in urine total thiols level in Koraga alcoholics compared to healthy controls (p<0.001). On Pearson’s correlation serum AST, serum ALT correlated positively with serum and urine GST (p<0.0001) and negatively with serum total thiols (p<0.0001). Serum GST correlated negatively with serum total thiols (p<0.0001). Conclusion: Results of our study possibly indicate that the extent of alcohol induced liver damage in Koraga subjects is comparatively lower than general alcoholics, even though the alcohol consumption is found to be higher in them. There may be some mechanism that is rendering them resistant to alcoholic liver damage which needs to be explored through further studies at molecular level

Determination of oxidative stress markers and their importance in early diagnosis of uremia-related complications

The existence of oxidative stress and the higher incidence of cardiovascular diseases in association with uremia is well proved. The uremic status of serum copper, ceruloplasmin (CP), protein thiols, malonyldialdehyde (MDA), and glutathione S-transferase (GST) levels was studied. The study was carried out on 51 chronic renal failure (CRF) patients who were not on hemodialysis therapy and on 42 healthy controls. Serum urea, creatinine, and MDA levels were found to be significantly increased (P < 0.001), and total protein, albumin, protein thiols, and copper levels were found to be significantly decreased in CRF patients compared to normal controls (P < 0.001). Ceruloplasmin levels were decreased significantly (P < 0.05), and there was no significant change in serum GST levels in CRF patients compared to normal controls. In conclusion, the significant increase in levels of MDA, and the decrease in levels of protein thiols, CP, and copper in uremia patients when compared to controls, reconfirms the presence of stress in this patient population. In view of the changes in other markers of oxidative stress, this absence of any significant change in the activity of GST in uremia patients compared to controls, warrants further study