The assessment of glutathione, glutathione peroxidase, glutathione reductase, and oxidized glutathione in patients with periodontitis-A systematic review and meta-analysis.

OBJECTIVE: The present systematic review explored the involvement of enzymatic and nonenzymatic antioxidants in periodontitis, drawing from established literature. MATERIALS AND METHODS: The research approach encompassed an extensive electronic search from 2000 to 2023 across databases such as PubMed, Science Direct, and Wiley Online Library and cross-referencing using specific keywords. RESULTS: The initial literature exploration generated a total of 766 articles. After thoroughly examining the abstracts, 693 articles were excluded from consideration due to duplication and lack of relevance to the central research inquiry. Following that, 73 articles were left for in-depth evaluation. Following a qualitative assessment, 35 studies that satisfied the inclusion criteria were chosen, while 38 were removed for not meeting the necessary standards. Within this selection, a meta-analysis was conducted on 11 articles that provided consistent data for quantitative synthesis. Specifically, the analysis of glutathione (GSH) levels in serum samples revealed a standardized mean difference (SMD) of -5.552 µg/mL (CI 95%: -9.078 to -2.026; P-0.002). In contrast, the analysis of glutathione peroxidase (GPx) enzymes in gingival crevicular fluid (GCF) samples displayed an overall SMD of 2.918 ng/µL (CI 95%: 0.372-5.465; P-0.025), while salivary samples exhibited an overall SMD value of 0.709 U/l (95% CI: -1.907-3.325; P-0.596) which is of insignificant. CONCLUSION: The systematic review findings suggest a notable decrease in antioxidant enzymes across various systemic biological samples among patients with periodontitis, contrasting with the results from gingival tissue samples meta-analysis of GPx enzyme.

Assessment of antioxidant system status before and after operation in neonates with congenital heart disease.

Background/Aim: Oxidative stress is considered to have a significant role in the development of cardiovascular diseases (CVDs) as well as many other diseases. Therefore, the purpose of the study is to evaluate the antioxidant system status at pre- and post-operative period in newborns with congenital heart disease (CHD) requiring operation. Materials and Methods: Fifty CHD patients participated in this research. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and thiobarbituric acid reactive substances (TBARS) levels were studied in blood samples. RACHS-1 score, blood lactate levels, and hypoxic events were also recorded. Comparisons of antioxidant system parameters were conducted at pre- and post-operative periods and also between exitus and discharged groups. Results: GPx activity and TBARS levels were significantly higher in the pre-operative period than post-operative period though the other antioxidant enzymes were not altered. In pre-operative period, GPx activity was low in addition to rarer hypoxic events in the discharged group. Also, a negative correlation was found between SOD and GPx activities in pre-operative period. Conclusion: The results provide fundamental data showing the lowered GPx activity and TBARS levels considered as sensitive oxidative biomarkers after the operation. It was assumed that antioxidant system parameters might show changes after the operation, and GPx is prominent for resistance to hypoxic conditions. Post-operative reduction of GPx and TBARS levels is significant for evaluating the antioxidant system alterations after the operation. However, further investigations follow long-term duration for post-operative monitoring to estimate how antioxidant system status changes to improve the treatment of the health condition.

Assessment of glutathione peroxidase enzyme response and total antioxidant status in oral cancer - Systematic review and meta-analysis.

BACKGROUND: Oxidative stress induced by free radical accumulation contributes to many pathologies, including cancer. Antioxidant defense system fails to scavenge free radicals when it is excessively accumulated. Assessing individual antioxidant enzymes and total antioxidant capacity could direct the customized therapeutic strategies. OBJECTIVE: Evaluation of total antioxidant status and enzyme glutathione peroxidase activity in the oral cancer group compared to the healthy control group. METHOD: The literature search included databases PubMed, Science Direct, Wiley Online Library, Cochrane and Cross Reference between 1999 and 2021. The database search was completed in the month of August 2022. The extracted data were analyzed by Comprehensive Meta-Analysis (CMA) version 3 software (Biostat Inc. Englewood, NJ). Based on search strategies, 1435 articles have been retrieved from the database. In the segregated articles, 1365 were excluded due to duplicated articles, animal studies, low-quality studies, articles unrelated to the research question, and with unmatched objectives. Based on inclusion criteria, 70 articles were selected for full-text valuation. However, 33 articles were found highly suitable for inclusion and data extraction. Finally, 11 articles were selected for meta-analysis. RESULTS: The meta-analysis of four included studies of tissue samples showed a significantly (p < .001) increased GPx activity in the oral cancer group, when compared to the control group, whereas three included studies of erythrocyte samples displayed a significantly (p < .001) decreased GPx activity in the oral cancer group than the control group with the pooled standardized mean difference value of -2.766 moles/min/g Hb at 95% CI (-3.297 to -2.234). The meta-analysis of the included studies depicted an insignificant (p = .947) reduction of salivary TAS levels in the oral cancer group when compared to the control group. CONCLUSION: Our systematic review and meta-analysis depict antioxidant GPx enzyme activity in the regional tissue samples of the oral cancer group differs from other systemic biological fluid samples compared to the healthy control group.

Assessment of the Antitumor Activity of Green Biosynthesized Zinc Nanoparticles as Therapeutic Agent Against Renal Cancer in Rats.

Zinc nanoparticles (Zn-NPs) have garnered a great deal of attention as potential cancer therapy. The use of microorganisms in the synthesis of nanoparticles emerges as an eco-friendly and exciting approach. This study was designed to assess biosynthesized Zn-NPs as therapeutic agent against kidney cancer induced by ferric-nitrilotriacetate (Fe-NTA) in rats.Zn-NPs were synthesized from edible mushroom then characterized by transmission electron microscopy analysis, dynamic light scattering, and Fourier transform infrared spectroscopy. Rats were divided into 4 different groups: group I (control), group II (Fe-NTA group), group III (Zn-NPs group), and group IV (Fe-NTA + Zn-NPs group). Animals were sacrificed then kidney and liver function tests, MDA level, glutathione, glutathione peroxidase, and superoxide dismutase activities were measured by using colorimetric methods. Caspase-3 level and carcinoembryonic antigen concentration were measured by using ELISA. Finally, DNA fragmentation was visualized by using agarose gel electrophoresis.Treatment with Zn-NPs significantly suppressed renal oxidative stress by restoring glutathione level, glutathione peroxidase, and superoxide dismutase activities and ameliorated oxidative damage parameters of lipid peroxidation as well as renal toxicity markers. Molecular and tumor markers showed significant improvement with respect to induction group, and this was well appreciated with the histopathological alteration findings in the treated groups.Microbial synthesized Zn-NPs possess antitumor-promoting activity against Fe-NTA-induced toxicity and carcinogenesis, which should be evaluated in a clinical study.

Assessment of Tissue Oxidative Stress, Antioxidant Parameters, and Zinc and Copper Levels in Patients with Breast Cancer.

Breast cancer is a multifactorial disease, and among the many factors which are involved in the onset, progression, and invasion of the disease, oxidative stress plays a significant role. The concentration and activity of enzymatic antioxidants are proportional to the concentration of trace elements, and the concentration of trace elements is often deficient in malignancies. Therefore, in the present study, we studied the tissue levels of oxidative stress, antioxidant status, zinc (Zn), and copper (Cu) in breast cancer patients. Tissue samples were collected from 40 patients with breast cancer and 40 tumor margin tissue as a control group. All subjects gave their informed consent. The tissue samples were measured for superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), total antioxidants capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), malondialdehyde (MDA), Zn, and Cu. Data of all biochemical parameters of two groups were statistically analyzed by SPSS software, t test, and GraphPad Prism. Concentrations of MDA, TOS, and OSI in tumor tissue were significantly higher than tumor margin tissue, but the level of TAC and CAT, SOD, and GPX activities was significantly reduced in tumor tissue (p<0.05). It was found that the concentrations of Zn and Cu in breast cancer patients were higher than tumor margin tissue. Patients with breast cancer have a rise in oxidative stress indicators and a decrease in antioxidant stress markers. Since oxidative stress is a significant contributor to the development and progression of breast cancer, more research might lead to a more effective method of breast cancer treatment. Considering the dual role of oxidative stress in cancer, which can both cause survival and adaptation, and the death of cancer cells, and with more information, it can be used to manage the treatment and destruction of cancer cells.

The distinct resistance mechanisms of cyanobacteria and green algae to sulfamethoxazole and its implications for environmental risk assessment.

Cyanobacteria and green algae are the OECD recommended test organisms for environmental toxicity assessments of chemicals. Whether the differences in these two species' responses to the identical chemical affect the assessment outcomes is a question worth investigating. Firstly, we investigated the distinct resistance mechanisms of Synechococcus sp. (cyanobacteria) and R. subcapitata (green algae) to sulfamethoxazole (SMX). The antioxidant system analysis demonstrated that R. subcapitata mainly relies on enhancing the activity of first line defense antioxidants, including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), which is the most powerful and efficient response to get rid of ROS, whereas Synechococcus sp. depends upon increasing the activity of glutathione-S-transferase (GST) and GPx to resist oxidative stress. Besides, a total 7 transformation products (TPs) of SMX were identified in R. subcapitata culture medium. The analysis of conjectural transformation pathways and the predicted toxicity indicates that R. subcapitata could relieve SMX toxicity by degrading it to low eco-toxic TPs. Additionally, we summarized numerous exposure data and assessed the environmental risk of various antibiotics, revealing an inconsistent result for the same type of antibiotic by using cyanobacteria and green algae, which is most likely due to the different resistance mechanisms. In the future, modified indicators or comprehensive assessment methods should be considered to improve the rationality of environmental toxicity assessments.

Assessment of Liver Antioxidant Profile in Plasmodium Berghei Infected Mice Treated with Curative Ethanol Leaf extract of Musa paradisiaca.

Background: The increasing resistance to most antimalarial drugs suggests a need for better alternatives. This study evaluated in vivo antimalarial and liver antioxidant profile of dry plantain leaf extract (Musa paradisiaca) on mice infected with Plasmodium berghei. Methods: Six groups of ten mice each grouped as control, P. berghei, artesunate, and P. berghei infected mice were orally administered 250,500 and 1000mg/kg Musa paradisiaca leaf extract for 5 days. Blood smears were evaluated for parasitaemia on the 10th day and the mice sacrificed. Catalase, Malondialdehyde, protein, Glutathione peroxidase and reduced glutathione was estimated using Colorimetric, Biuret and spectrophotometric methods respectively with data analyzed using SPSS version 21. Results: Catalase activity (umol/ml/mins) was 24.62 ± 0.99, 10.04 ± 0.50, 19.35 ± 0.38, 22.13 ± 0.00, 22.79 ± 0.00 and 23.66 ± 0.20 while Glutathione Peroxidase(u/l) was 332.34± 0.64, 205.22± 4.61, 218.26± 0.63, 310.59± 0.00, 305.20± 0.00. and 295.97± 0.02 at Control, P.berghei, artesunate, 250mg, 500mg and1000mg extracts. Glutathione (mM) was 1.60 ± 0.12, 0.64 ± 0.09, 1.06 ± 0.16, 0.72 ± 0.00, 0.92 ± 0.00 and 1.26 ± 0.08 while Malondialdehye (uM) was 16.93 ± 3.59, 61.65 ± 1.72, 27.80 ± 0.26, 36.90 ± 0.00, 34.30 ± 0.00 and 32.68 ± 0.27 and Protein(g/dl) was 22.37 ± 1.87, 7.91 ± 0.13, 11.78 ± 1.19, 11.79 ± 0.00, 13.20 ± 0.00 and 17.04 ±0.03 at control, P.berghei, artesunate, 250mg, 500mg and1000mg respectively. Conclusion: The study suggested that ethanolic extract of Musa paradisiaca reduced liver oxidative stress caused by P.berghei.

Assessment of redox state and biochemical parameters of salivary glands in streptozotocin-induced diabetic male rats treated with mate tea (Ilex paraguariensis).

OBJECTIVE: The study aimed to assess the effects of mate tea [Ilex paraguariensis] on the redox state and biochemical parameters of salivary glands in diabetic male rats. DESIGN: Twenty-four male Wistar rats (3 months old) were randomly divided into groups (n = 8 per group): control rats that received water (C); diabetic rats that received water (D); diabetic rats treated with mate tea (DMT). The treated streptozotocin-induced diabetic rats were given mate tea powder by intragastric gavage at a dose of 20 mg/kg daily for 28 days. Content of total protein, amylase, oxidative lipid damage, measured as thiobarbituric acid reactive substances (TBARs), oxidative protein damage, measured as protein carbonyl, total antioxidant capacity, uric acid, reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were examined by the spectrophotometric method in the parotid and submandibular glands. RESULTS: The D group showed lower total protein, amylase, TBARs, protein carbonyl, total antioxidant capacity, GSH, uric acid, and GPx than the C group in both salivary glands, as well as higher SOD and CAT activities. The DMT group showed higher total protein, amylase, total antioxidant capacity, GSH, uric acid, and GPx than the D group in both salivary glands. Moreover, mate tea increased SOD in the parotid gland and CAT in the submandibular gland of diabetic rats but did not influence TBARs and protein carbonyl in either salivary gland compared to D group. CONCLUSION: Mate tea increased tissue protein synthesis and improved antioxidant defenses in the salivary glands of streptozotocin-induced diabetic male rats.

In vivo toxicity assessment of Remazol Gelb-GR (RG-GR) textile dye in zebrafish embryos/larvae (Danio rerio): Teratogenic effects, biochemical changes, immunohistochemical changes.

Dyes, which are very important for various industries, have very adverse effects on the aquatic environment and aquatic life. However, there are limited studies on the toxic properties of dyes on living things. This research elucidated the sublethal toxicity of acute exposure of the textile dye remazol gelb-GR (RG-GR) using zebrafish embryos and larvae for 96 h. The 96 h-LC50 for RG-GR in zebrafish embryos/larvae was determined to be 151.92 mg/L. Sublethal 96 hpf exposure was performed in RG-GR concentrations (0.5; 1.0; 10.0; 100.0 mg/L) to determine the development of toxicity in zebrafish embryos/larvae. RG-GR dye affected morphological development, and decreased heart rate, hatching, blood flow, and survival rates in zebrafish embryos/larvae. The immunopositivity of 8-hydroxy 2 deoxyguanosine (8-OHdG) in larvae exposed to RG-GR at high concentrations was found to be intense. Depending on the RG-GR dose increase, some biochemical parameters such as glutathione peroxidase (GSH) level, acetylcholinesterase (AChE) activity, catalase (CAT) activities, superoxide dismutase (SOD), and nuclear factor erythroid 2 (Nrf-2) levels were detected to be decreased in larvae, while malondialdehyde (MDA) content, nuclear factor kappa (NF-kB), tumor necrosis factor-α (TNF-α), DNA damage (8-OHdG level), interleukin-6 (IL-6) and apoptosis (Caspase-3) levels were found to be increased. The experimental results revealed that RG-GR dye has high acute toxicity on zebrafish embryo/larvae.

Biochemical and molecular assessment of selenium forms for the alleviation of oxidative stress in senescent human fibroblasts.

Selenium enhances the cellular antioxidant capacity and alleviates oxidative stress. We investigated the transcriptional and enzymatic activities of selenium-dependent glutathione peroxidase 1 and thioredoxin reductase 1 (TrxR1), and levels of glutathione, hydrogen peroxide, lipid peroxides, and protein carbonyls in primary passage 5 (P5) and senescent passage 25 (P25) and 30 (P30) fibroblasts. Cells were incubated in either standard Dulbecco growth medium (CM1) containing normal plasma selenium levels (0.8 µmol/l), or in CM2, CM3, and CM4 containing 3 µmol/l (5 µmol/l for TrxR1) sodium selenite, L-hydroxyselenomethionine, or Se-methylselenocysteine, respectively. Gene transcripts and activities of both investigated enzymes as well as the levels of reduced glutathione were significantly increased in CM2-, CM3-, and CM4-incubated senescent P25 and P35 cells compared against those incubated in CM1. In congruence, although all oxidative stress parameters including oxidized glutathione were significantly lower in CM2-, CM3-, and CM4-incubated senescent cells compared against those incubated in CM1, such reductions were of significantly higher magnitude in CM3 and CM4 cells compared against those in CM2. In conclusion, organic L-hydroxyselenomethionine and Se-methylselenocysteine are equally more potent at alleviating oxidative stress in senescent cells than inorganic sodium selenite, and thus could be beneficial for use in elderly subjects and those with oxidative stress-associated disease.

Comparative assessment of cognitive impairment and oxidative stress markers among vitamin D insufficient elderly patients with and without type 2 diabetes mellitus (T2DM).

BACKGROUND: Disorders of mental health are known to affect cognitive functions, hence called as cognitive disorders. Impaired glucose metabolism, insulin resistance, vitamin-D deficiency and oxidative stress are some of the key early events reported to be involved in the pathogenesis of most common cognitive disorders, which include Alzheimer's disease. Type-2 diabetes mellitus (T2DM) is one of the known contributing factors of cognitive impairment and dementia. METHODS: A cross sectional study was carried out in 145 subjects, who were assessed for cognitive function by modified mini mental status examination (3MS). In addition, measurement of fasting blood sugar (FBS), fasting insulin, HbA1c, lipid profile, vitamin D and oxidative markers was performed. Participants were divided into different groups based on (a) vitamin D insufficiency and sufficiency; (b) diabetic and non-diabetic with and without cognitive impairment. RESULTS: The study included a total of 145 subjects; 51 males and 94 females and the mean age was 68.24±9.70 years. Among diabetics with vitamin D insufficiency, 35 subjects (71.43%) had cognitive impairment, but, among non-diabetics with vitamin D insufficiency, 27 subjects (62.79%) had cognitive impairment. Chi square test showed no significant association between diabetes, vitamin D insufficiency and cognitive impairment. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels were non-significantly lower in cognition-impaired subjects, when compared to cognition normal subjects in diabetics with vitamin D insufficiency. CONCLUSION: Our study showed that cognitive impairment is more predominant in individuals with diabetes. However, our study did not find any significant relationship between T2DM, vitamin D deficiency, cognitive impairment, and oxidative stress. A significant association was found only with GPx and 3MSE score in vitamin D insufficient non-diabetics.

Assessment of the effect of perineural dexmedetomidine on oxidative stress during peritoneal dialysis catheter insertion: a randomized, controlled trial.

PURPOSE: This study aimed to evaluate the effect of the addition of dexmedetomidine to ropivacaine on oxidative stress during transversus abdominis plane (TAP) and rectus sheath (RS) blockades for patients with end-stage renal disease (ESRD) undergoing peritoneal dialysis (PD) catheter insertion. METHODS: Sixty patients with ESRD undergoing PD catheter insertion to receive left ultrasound-guided TAP and RS blockades were randomly divided into two groups: the dexmedetomidine plus ropivacaine group (25 mL of 0.3% ropivacaine + 1 µg/kg dexmedetomidine) and the ropivacaine group (25 mL of 0.3% ropivacaine). Primary outcomes were oxidative stress marker levels during the procedure. RESULTS: A total of 60 patients (30 patients in each group) were evaluated. Compared with the ropivacaine group, the dexmedetomidine plus ropivacaine group had significantly lower serum malondialdehyde levels (P < 0.05) and increased glutathione peroxidase (P < 0.01) and superoxide dismutase levels at 24 h after the procedure (P < 0.01). CONCLUSION: The addition of 1 µg/kg of dexmedetomidine to ropivacaine for ultrasound-guided TAP and RS blockades could inhibit oxidative stress in patients with ESRD undergoing PD catheter insertion. Trial registration This study was registered at www.chictr.org.cn on June 7, 2021 (ChiCTR2100047050).

Assessment of redox state and biochemical parameters of salivary glands in rats treated with anti-obesity drug sibutramine hydrochloride.

OBJECTIVES: To investigate the effects of anti-obesity drug sibutramine hydrochloride (SB) on redox state and biochemical parameters in the salivary glands. MATERIALS AND METHODS: Adult male Wistar rats were randomly divided into the following groups (n = 8 per group): control rats treated with vehicle (C) and rats treated with SB (10 mg/kg/day) by intragastric gavage for 28 days. The parotid (PG) and submandibular (SMG) glands were processed using histomorphometric analysis, and total protein, amylase, mucin, and oxidative damage to lipids were determined by measuring the formation of thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), uric acid (UA), total glutathione (tGSH), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), and AKT phosphorylation. RESULTS: SB decreased the acinar area, and increased the stromal area in PG, while no effect on the morphometric parameters was observed in SMG. SB also increased oxidative damage to lipids (TBARs). The SB group showed lower total protein, amylase, TAC, UA, tGSH, SOD, CAT, and GPx than the C group in PG, while in SMG, SB decreased total protein, mucin, tGSH, SOD, CAT, and GPx. However, increased AKT phosphorylation observed in both salivary glands suggests that SB exerts low-intensity oxidative stress. CONCLUSIONS: SB impaired enzymatic and non-enzymatic antioxidant defenses in the salivary glands of rats. CLINICAL RELEVANCE: Chronic treatment with SB could mitigate salivary gland dysfunction due to disturbance of redox state.

An Assessment of GPX1 (rs1050450), DIO2 (rs225014) and SEPP1 (rs7579) Gene Polymorphisms in Women with Endometrial Cancer.

BACKGROUND: Numerous studies indicate a relationship between the presence of GPX1 (rs1050450), DIO2 (rs225014) and SEPP1 (rs7579) gene polymorphisms and the development of chronic or neoplastic diseases. However, there are no reports on the influence of these polymorphisms on the development of endometrial cancer. METHODS: 543 women participated in the study. The study group consisted of 269 patients with diagnosed endometrial cancer. The control group consisted of 274 healthy women. Blood samples were drawn from all the participants. The PCR-RFLP method was used to determine polymorphisms in the DIO2 (rs225014) and GPX1 (rs1050450) genes. The analysis of polymorphisms in the SEPP1 (rs7579) gene was performed by means of TaqMan probes. RESULTS: There was a 1.99-fold higher risk of developing endometrial cancer in CC homozygotes, DIO2 (rs225014) polymorphism (95% Cl 1.14-3.53, p = 0.017), compared to TT homozygotes. There was no correlation between the occurrence of GPX1 (rs1050450) and SEPP1 (rs7579) polymorphisms and endometrial cancer. CONCLUSION: Carriers of the DIO2 (rs225014) polymorphism may be predisposed to the development of endometrial cancer. Further research confirming this relationship is recommended.

Altered Oxidative Status as a Cost of Reproduction in a Seabird with High Reproductive Costs.

AbstractLife history theory posits that reproduction is constrained by a cost of reproduction such that any increase in breeding effort should reduce subsequent survival. Oxidative stress refers to an imbalance between the prooxidant reactive oxygen species (ROS) and antioxidant defense. If not thwarted, ROS can cause damage to DNA, lipids, and proteins, potentially increasing the rate of senescence and decreasing cellular function. Reproduction is often associated with higher metabolic rates, which could increase production of ROS and lead to oxidative damage if the animal does not increase antioxidant protection. Thus, oxidative stress could be one mechanism creating a cost of reproduction. In this study we explored how reproduction may affect oxidative status differently between male and female thick-billed murres during early and late breeding seasons over three consecutive years. We manipulated breeding efforts by removing an egg from the nest of some individuals, which forced females to relay, and by handicapping other individuals by clipping wings. We measured total antioxidant capacity (TAC), uric acid (UA) concentration, and malondialdehyde (MDA; an index of lipid oxidative damage) concentration in blood plasma as well as activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) in red blood cells. Oxidative status was highly variable across years, and year was consistently the most important factor determining oxidative status; inconsistent results in previous field studies may be because reproductive oxidative stress occurs only in some years. Females had lower SOD and GPx and higher MDA and TAC than males immediately after egg laying, suggesting that the cost of egg laying required investment in cheaper nonenzymatic antioxidant defenses that had lower capacity for defending against lipid peroxidation. Delayed birds had lower UA and lower SOD, GPx, and CAT activity compared with control birds. In conclusion, when reproductive costs increase via higher energy costs or longer breeding seasons, the oxidative status of both male and female murres deteriorated as a result of reduced antioxidant defenses.

Assessment of serum catalase, reduced glutathione, and superoxide dismutase activities and malondialdehyde levels in keratoconus patients.

BACKGROUND: The aim of this study was to investigate the relationship between keratoconus disease and the antioxidant activities of catalase (CAT), reduced glutathione (GSH) and superoxide dismutase (SOD) and the level of the oxidative stress marker malondialdehyde (MDA) in serum. METHODS: The study included 50 patients diagnosed with keratoconus and 53 healthy age- and sex-matched control subjects. The keratoconus patients were grouped according to the four keratoconus stages based on the modified Krumeich keratoconus classification system. The CAT, GSH and SOD activities and MDA levels in the serum samples collected from the patient and control groups were compared. RESULTS: The mean serum CAT, GSH, SOD and MDA levels in the keratoconus group were determined to be 0.075 (0.074-0.078)U/L, 0.002 (0.001-0.006) mmol/ml, 1.56 (1.51-1.62)U/L and 1.69 (1.65-1.99) mmol/L, respectively, and those in the control group were determined to be 0.024 (0.013-0.037)U/L, 0.029 (0.018-0.049) mmol/ml, 4.13 (4.01-4.17) U/L and 0.74 (0.65-0.82) mmol/L. The serum GSH levels and SOD activity were significantly lower in the keratoconus group (p < 0.001 for both) than in the control group while the CAT activity and MDA levels were significantly higher (p < 0.001 for both). CONCLUSION: The low serum GSH levels and SOD activity and the high CAT activity and MDA levels observed in this study suggest the presence of oxidative stress and inadequate antioxidant defence mechanisms in keratoconus patients. The studied parameters may offer auxiliary markers for use in the diagnosis and treatment of the keratoconus disease and in its potential therapeutic targets in the future.

In vitro assessment of synergistic effects in combinations of a temoporfin-based photodynamic therapy with glutathione peroxidase 1 inhibitors.

BACKGROUND: Due to an increased elimination of reactive oxygen species (ROS), in particular hydrogen peroxide (H2O2), overexpression of glutathione peroxidase 1 (GPX1) can lead to an attenuation of apoptosis and development of resistance in cancer cells, thereby promoting tumor cell survival. Consequently, GPX1 inhibitors have the potential to be used in cancer therapy as they support oxidative stress in cancer cells. Similarly, photodynamic therapy (PDT) induces oxidative stress in cancer cells by the formation of ROS upon illumination. Thus, both methods of treatment might act in synergy when used in combination. METHODS: To investigate this hypothesis, combinations of the known GPX1 inhibitors 9-chloro-6-ethyl-6H-[1,2,3,4,5]pentathiepino[6,7-b]indole (CEPI) or mercaptosuccinic acid (MSA) with PDT induced by the photosensitizer (PS) temoporfin (5,10,15,20-tetra(m-hydroxyphenyl)chlorin, mTHPC) were studied in vitro. This new combinatory approach was intended to accumulate ROS formed during PDT via blockage of GPX1-catalyzed H2O2 degradation, and thus to enhance PDT-induced phototoxicity. Five human cancer cell lines from tumor origins treatable with PDT were utilized to investigate ROS generation, apoptosis induction, and cell cycle distribution. RESULTS: Synergy was identified with both GPX1 inhibitors, but not in all cell lines. ROS levels were increased after combined treatment with mTHPC and CEPI, but not MSA, in some cell lines, indicating that oxidative stress and ROS accumulation were enhanced by CEPI. Surprisingly, enhanced apoptosis induction was also observed with MSA afterwards, suggesting that other pathways contributed to the initiation of apoptosis. Cell cycle analysis confirmed apoptosis induction via the detection of DNA fragmentation. CONCLUSION: A combination of GPX1 inhibitors with mTHPC-PDT has the potential to generate synergistic effects and to increase overall phototoxicity, but the success of this combination approach was dependent on cancer type, and even antagonistic effects can occur.

An assessment of serum oxidative stress and antioxidant parameters in patients undergoing treatment for cervical cancer.

OBJECTIVES: Oxidative stress and antioxidants are involved in all aspects of cervical cancer. The present study evaluated serum levels of oxidative stress and antioxidant biomarkers in cervical cancer patients and healthy controls. Moreover, the effect of Concurrent chemoradiotherapy (CCRT) on these biomarkers and their association with treatment outcome was investigated. DESIGN: This study included ninety-seven cervical cancer patients and thirty controls. Three oxidative stress parameters (8-hydroxy-2-deoxyguanosine, Protein Carbonyl, and Malondialdehyde) and four antioxidant parameters (Superoxide Dismutase, Catalase, Glutathione Peroxidase, and Total Antioxidant Status) were measured. The analysis was conducted using repeated measures ANOVA for comparing among the phases (before, during, and follow-up) of treatment. The control group was compared using the Dunnet test. Logistic regression analysis was also conducted between oxidative stress and antioxidant parameters to study their association. RESULTS: Significant rises in oxidative damage markers were observed in cervical cancer patients of all stages, compared to controls. There was a further increase in oxidative stress markers during CCRT among complete responders. However, among non-responders, the oxidative stress biomarkers like Protein Carbonyl and Malondialdehyde were unaltered during CCRT. Simultaneously, there was a significant decrease in antioxidant parameters in cervical cancer patients of all stages compared to controls. During CCRT, antioxidant levels continuously depleted among complete responders. Nevertheless, in non-responders, antioxidant parameters like Superoxide Dismutase and Total Antioxidant Status were consistent. The oxidative stress markers and antioxidant parameters normalized among complete responders at six months follow up. While in non-responders, the normalization of these parameters was not observed. CONCLUSION: Our results indicate that increased oxidative stress and diminished antioxidants among patients were associated with carcinoma cervix. Induced oxidative stress and decreased antioxidant parameters during CCRT among the complete responders show the treatment's efficacy. Oxidant-antioxidant profile merits investigation as markers of diagnosis, treatment response, survival, and recurrence in extensive prospective studies.

Assessment of DNA damage profile and oxidative /antioxidative biomarker level in patients with inflammatory bowel disease.

<b>Aim:</b> The purpose of this study was to investigate the oxidative DNA damage, pro-antioxidant status in Polish patients with inflammatory bowel disease (IBD). <br><b>Methods:</b> Oxidative DNA damage was measured by comet assay techniques; nitric oxide (NO) and plasmatic lipid peroxidation (MDA) as oxidative stress were valuated by colometric methods; superoxide dismutase (SOD1), catalase (CAT) and glutathione peroxidase (GPx1) as antioxidative defense were determined by spectrophotometric methods. <br><b>Results:</b> The level of oxidative DNA damage in IBD patients was significantly higher in relation to controls (P = 0.01). Alike, in control subject as well as in patients with IBD, lymphocytes are characterized by complete repair of DNA damage. A significant decrease of SOD (P = 0.031), CAT (P = 0.006), GPx1 (P = 0.001) activity was seen in IBD patients vs control. MDA (P = 0.001) and NO (P = 0.001) concentrations were significantly increased in IBD patients as compared to healthy subjects. <br><b>Conclusions:</b> Our results may be due to the induction of DNA repair genes which may occur at the stage of the pathological changes (IBD) that may be caused by excessive oxidative stress. However, the cause of this relationship, and whether it is direct or indirect, remains to be explored.

Assessment of physiological age and antioxidant status of new somatic hybrid potato seeds during extended cold storage.

Yield components of potato are largely affected by the physiology age of the tuber seeds at planting. The current study focuses on monitoring seed tuber aging in two CN1 and CN2 somatic hybrid lines and Spunta (Sp) variety during 270 days of storage at 4 °C. Aging rate was monitored based on sprouting, emergence and tissue oxidation rates. Investigation of sprouting parameters such as physiological age index (PAI) considering physiological and chronological age and the incubation period (IP) indicated lower physiological age in hybrids than in Sp during the storage. Moreover, these analyses showed that off-seasonal growing conditions increased the aging, more clearly, in Sp tubers than in hybrid ones. However, dormancy periods (endodormancy and after storage dormancy) were equivalent in the different tuber lots. PAI and IP data when combined with those from emergence parameters (duration until emergence and stem number) seem more efficient for the characterization of the different potato lines. However, emergence indicators, when considered separately, were not able to distinguish clearly between seasonal and off-seasonal tubers. Data suggest that hybrid seeds exhibited high performances since they produced higher stem number per plant than Sp. The high aging rate in Sp tubers seems to be associated with the few developed stems. Biochemical analyses supported in part morphophysiological differences between hybrids and Sp seeds although these indicators seem more sensitive to aging. Indeed data showed that the dormancy break, and then, the development were associated with some level of tissue oxidation. Antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and carotenoids seem more enhanced after the release of dormancy. However, induction of these activities started earlier in off-seasonal tubers than in seasonal ones, this was consistent with their advanced aging level revealed by PAI and IP data. Activation of these antioxidants appears to respond effectively to the increase of ROS suggesting a better control of postharvest development and tissue deterioration especially in CN2 off-seasonal tubers. This study suggests that CN2 followed by CN1 exhibited the best performance compared to Sp variety.