Oxidative stress induction by essential oil from Piper alatipetiolatum (Piperaceae) triggers lethality in the larvae of Culex quinquefasciatus (Diptera: Culicidae).

Culex quinquefasciatus is the main vector of lymphatic filariasis in Brazil, which present resistance to commercial insecticides. Nowadays, essential oils (EOs) exhibiting larvicidal activity, such as those derived from Piper alatipetiolatum, provide a promising alternative for vector control, including Culex species. This study aimed to investigate the larvicidal activity and the oxidative stress indicators of the EO from P. alatipetiolatum in Cx. quinquefasciatus larvae. The EO was extracted from P. alatipetiolatum leaves using the hydrodistillation method, resulting in a yield of 7.2 ± 0.1%, analysed by gas chromatography coupled with spectrometry and gas chromatography coupled with flame ionization detector (GC-MS and GC-FID), and evaluated against Cx. quinquefasciatus larvae. Reactive Oxygen and Nitrogen Species (RONS), Catalase (CAT), glutathione-S-transferase (GST), acetylcholinesterase (AChE), and Thiol levels were used as oxidative stress indicators. Analysis by CG-MS and CG-FID revealed that the main compound in the EO was the oxygenated sesquiterpene ishwarone, constituting 78.6% of the composition. Furthermore, the EO exhibited larvicidal activity, ranging from 26 to 100%, with an LC50 of 4.53 µg/mL and LC90 of 15.37 µg/mL. This activity was accompanied by a significant increase in RONS production, alterations in CAT, GST, AChE activity, and thiol levels compared to the control groups (p < 0.05). To the best of our knowledge, this is the first report describing the larvicidal activity and oxidative stress induced by the EO from P. alatipetiolatum against Cx. quinquefasciatus larvae. Therefore, we propose that this EO shows promise as larvicidal agent for the effective control of Cx. quinquefasciatus larvae.

Evaluating oxidative stress biomarkers in oncology nurses exposed to antineoplastic drugs: A cross-sectional study.

PURPOSE: Antineoplastic drugs (ADs) are widely used in cancer treatment. Nurses in chemotherapy centers are exposed to these drugs during preparation. They can affect healthy cells, leading to teratogenic and mutagenic effects, as well as oxidative stress. This study aimed to evaluate oxidative stress biomarkers in the nurses exposed to these drugs. METHOD: This study was conducted on 30 nurses exposed to ADs and 30 nurses with no exposure to these drugs as non-exposed group. Oxidative stress biomarkers were measured in the blood serum samples of both groups, including malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and blood thiol groups. RESULTS: Considering the possibility of confounding effect of nutritional supplement consumption, the effect of this factor was adjusted in the analysis. A significant difference was observed for CAT, SOD, thiol, and TAC biomarkers between two groups (P < 0.05). However, the difference in MDA and GPx biomarkers between two groups was not statistically significant. CONCLUSIONS: The findings of the present study showed that supplement consumption has a significant effect on the biomarker of total antioxidant capacity. Thus, total antioxidant capacity measurement is advised as the best biomarker for tracking oxidative status in nurses exposed to ADs due to its capacity to measure all antioxidants in the body, except the thiol group, and its lower cost when compared to other biomarkers. Furthermore, it can be claimed that the consumption of nutritional supplements has a greater effect on the non-enzymatic biomarkers of oxidative stress than on enzymatic antioxidant system.

Redox processes are major regulators of leukotriene synthesis in neutrophils exposed to bacteria Salmonella typhimurium; the way to manipulate neutrophil swarming.

Neutrophils play a primary role in protecting our body from pathogens. When confronted with invading bacteria, neutrophils begin to produce leukotriene B4, a potent chemoattractant that, in cooperation with the primary bacterial chemoattractant fMLP, stimulates the formation of swarms of neutrophils surrounding pathogens. Here we describe a complex redox regulation that either stimulates or inhibits fMLP-induced leukotriene synthesis in an experimental model of neutrophils interacting with Salmonella typhimurium. The scavenging of mitochondrial reactive oxygen species by mitochondria-targeted antioxidants MitoQ and SkQ1, as well as inhibition of their production by mitochondrial inhibitors, inhibit the synthesis of leukotrienes regardless of the cessation of oxidative phosphorylation. On the contrary, antioxidants N-acetylcysteine and sodium hydrosulfide promoting reductive shift in the reversible thiol-disulfide system stimulate the synthesis of leukotrienes. Diamide that oxidizes glutathione at high concentrations inhibits leukotriene synthesis, and the glutathione precursor S-adenosyl-L-methionine prevents this inhibition. Diamide-dependent inhibition is also prevented by diphenyleneiodonium, presumably through inhibition of NADPH oxidase and NADPH accumulation. Thus, during bacterial infection, maintaining the reduced state of glutathione in neutrophils plays a decisive role in the synthesis of leukotriene B4. Suppression of excess leukotriene synthesis is an effective strategy for treating various inflammatory pathologies. Our data suggest that the use of mitochondria-targeted antioxidants may be promising for this purpose, whereas known thiol-based antioxidants, such as N-acetylcysteine, may dangerously stimulate leukotriene synthesis by neutrophils during severe pathogenic infection.

The effects of orlistat on oxidative stress, recognition memory, spatial memory and hippocampal tissue in experimentally induced obesity in rats.

This study investigates the impact of orlistat on oxidative stress, spatial memory, recognition memory, and hippocampal tissue in obese rats. The study groups were divided into control, high fat diet-induced obese (HFDIO), HFDIO+orlistat (HFDIO+ORL) groups, each consisting of 8 animals. While control fed with standart diet, HFDIO and HFDIO+ORL fed with high-fat diets for 8 weeks to induce obesity. Then, ORL treated 10 mg/kg for 7 weeks, while control and HFDIO get water. At 16th week, novel object recognition (NOR) and Morris water maze (MWM) tests were performed. TNF-alpha, IL-1beta levels in hippocampal tissue, and total/native thiol/disulphide levels in serum were measured. TNF-alpha level of HFDIO was higher than control, while lower in HFDIO+ORL compared to HFDIO as like IL-1beta level. On the contrary, serum total thiol level was lower in HFDIO than control and higher in HFDIO+ORL compared to the HFDIO, while disulphide level was opposite of the total thiol levels. While recognition index was higher in HFDIO+ORL, in MWM, latency of finding platform in HFDIO was higher than control and latency of HFDIO+ORL was very similar to control in 2-4 days. The HFDIO group demonstrated decrease in time spent in platform zone compared to control, whereas time spent of the HFDIO+ORL was higher than HFDIO. Our study demonstrates that orlistat administration exerts beneficial effects on oxidative stress, spatial memory, recognition memory, and hippocampal tissue in obese rats. It shows that orlistat may have potential therapeutic implications for obesity-related cognitive impairments and hippocampal dysfunction.

The effect of slow-release vaginal dinoprostone on maternal and fetal oxidative stress in term pregnancies complicated by oligohydramnios: Prospective cohort study.

BACKGROUND: To evaluate changes in oxidant status using thiol/disulfide homeostasis in mothers and fetuses after induction of labor with slow-release vaginal dinoprostone inserts. METHODS: A total of 70 pregnant women were divided into two groups. Thirty-five women in whom labor was induced with slow-release vaginal dinoprostone inserts (10 mg of prostaglandin E2, group A) were compared before and after the administration. The other 35 women, who were followed up spontaneously during labor (group B), were included as a control group. Both groups were diagnosed with isolated oligohydramnios without signs of placental insufficiency. The thiol/disulfide homeostasis parameters were calculated before medical induction and after removal of the insert at the beginning of the active phase of labor. Maternal and cord blood values were measured in both groups. RESULTS: Although the balance shifted to the antioxidant side after the slow-release vaginal dinoprostone insert was applied, there was no significant difference in maternal oxidative load compared to the pre-application status (5.32 ± 014/5.16 ± 0.15, p = 0.491). Despite the shift toward the antioxidant side, maternal antioxidants were still significantly lower in the group that received slow-release vaginal dinoprostone at the beginning of the active phase of labor than in the control group (295.98 ± 13.03/346.47 ± 12.04, respectively, p = 0.009). There was no statistically significant difference in terms of oxidative balance or newborn Apgar score ( p > 0.05). CONCLUSION: Induction of labor with slow-release vaginal dinoprostone inserts in pregnancies with isolated oligohydramnios does not cause further oxidative stress and is safe for both mothers and neonates in terms of oxidant load by thiol/disulfide homeostasis.

Mitochondrial-targeted curcumin inhibits T-cell activation via Nrf2 and inhibits graft-versus-host-disease in a mouse model.

Anti-inflammatory and immune suppressive agents are required to moderate hyper-activation of lymphocytes under disease conditions or organ transplantation. However, selective disruption of mitochondrial redox has not been evaluated as a therapeutic strategy for suppression of T-cell-mediated pathologies. Using mitochondrial targeted curcumin (MitoC), we studied the effect of mitochondrial redox modulation on T-cell responses by flow cytometry, transmission electron microscopy, transcriptomics, and proteomics, and the role of Nrf2 was studied using Nrf2- /- mice. MitoC decreased mitochondrial TrxR activity, enhanced mitochondrial ROS (mROS) production, depleted mitochondrial glutathione, and suppressed activation-induced increase in mitochondrial biomass. This led to suppression of T-cell responses and metabolic reprogramming towards Treg differentiation. MitoC induced nuclear translocation and DNA binding of Nrf2, leading to upregulation of Nrf2-dependent genes and proteins. MitoC-mediated changes in mitochondrial redox and modulation of T-cell responses are abolished in Nrf2- /- mice. Restoration of mitochondrial thiols abrogated inhibition of T-cell responses. MitoC suppressed alloantigen-induced lymphoblast formation, inflammatory cytokines, morbidity, and mortality in acute graft-versus-host disease mice. Disruption of mitochondrial thiols but not mROS increase inculcates an Nrf2-dependent immune-suppressive disposition in T cells for the propitious treatment of graft-versus-host disease.

Construction of durable antibacterial cellulose textiles through grafting dynamic disulfide-containing amino-compound and nanosilver deposition.

Cotton textile is very comfortable to wear, and also provides an ideal environment for bacterial propagation, easily causing harm to human health. In order to address this issue, various antibacterial techniques are employed for cotton finishing. However, some processes are complex and involve the use of environmentally unfriendly chemicals. In this work, a durable and efficient antibacterial cotton fabric was prepared via grafting of an amino-compound containing dynamic disulfide bonds, and then in-situ deposition of silver nanoparticles (AgNPs). Briefly, the reactive α-lipoic acid-modified polyethyleneimine (mPEI) was introduced to the cotton fibers via thiol-ene click reaction. Subsequently, the amino groups and dynamically-generated sulfhydryl groups in the mPEI molecules were used to initiate the ultrafast reduction of silver ions without the participation of additional reductant, constructing a stable antibacterial layer on fiber surface. The results reveal that the amino and thiol groups of mPEI could form coordination bonds with the deposited silver nanoparticles, and the antibacterial ability of AgNP@cotton-g-mPEI fabric remains at a high level even after 20 washing cycles. After 30 min of contact with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), the antibacterial rates against both bacteria reached 99.99 %. Meanwhile, the network matrix constructed by the recombination of the dynamic disulfide bonds in mPEI endows the cotton fabric with detectable wrinkle resistance and encouraging anti-ultraviolet effect. The present work provides a novel alternative for preparation of durable and efficient antibacterial textiles.

Macrophages morphology and cytokine reeducation by ex situ copper thiol complexes.

OBJECTIVE: To study the reeducation effect of copper thiol complexes on macrophage morphology and cytokine expression. METHODS: The effect of copper thiol complexes was assessed on murine macrophages by the cell morphology observed through optical microscopy, while the expression of cytokines by protein abundance after stimulation. A viability experiment was performed on PMBC to confirm that copper complexes do not affect other cells. RESULTS: The M1 shape was reported after treatment with copper thiol complexes at 1-200 µM, while M2 behavior was documented between 50 and 800 µM. Surprisingly, a thin elongate morphology was observed between 400-800 µM like the M2 shape. The expression of M1 cytokines was noted ranging from 1 to 100 µM, with the highest yield at 1 µM (2243 pg/µL) for the copper-penicillamine complex. M2 production behavior was observed at 1-800 µM, with the highest abundance close to 1150 pg/µL (200-400 µM) was quantified from the copper-cysteine complex. Finally, LCCu complexes did not induce a cytotoxic response on PBMC while exhibiting a high IL-4 and IL-10 production, similar to their gold analogs. CONCLUSIONS: The capacity of copper thiol complexes to reeducate M1 to M2 morphoexpression can be promising for cell protection by using copper thiol penicillamine or immuno-regeneration of tissues when using copper thiol cysteine.

Cemtirestat dimerization in liposomes and erythrocytes exposed to peroxyl radicals was reverted by thiol-disulfide exchange with GSH.

In the model system of DOPC (1,2-dioleoyl-sn-glycero-3-phosphocholine) liposomes exposed to peroxyl radicals generated by the azoinitiator AAPH, cemtirestat (CMTI-SH) inhibited lipid peroxidation more efficiently than the natural antioxidant glutathione. In the concentrations 100 to 500 µM, both CMTI-SH and GSH induced distinct lag phases in the initial stages of lipid peroxidation yet GSH produced consistently shorter induction periods (about twice) than equimolar CMTI-SH. Moreover, concentration dependence of lipid peroxidation inhibition measured at the 80th minute, revealed about three times higher IC50 value for GSH compared to CMTI-SH. When the incubations prolonged till 180 min no further absorbance changes at 270 and 302 nm, respectively, occurred. After addition of the reducing agent tris(2-carboxyethyl)phosphine, the absorbance peak at 270 nm shifted back to 302 nm. These findings pointed to the presence of reducible CMTI-SH disulfide whose definite structure was confirmed by proving identity of TLC retention and spectral data with those of the synthesized CMTI disulfide. When CMTI-SH and GSH were present simultaneously in the liposomal incubations, the mixing effect on the induction period was synergistic rather than additive. This was explained by ability of GSH to reduce CMTI disulfide which was proved in separate experiments with an authentic CMTI disulfide prepared synthetically. This finding was also demonstrated by experiment with CMTI-disulfide to protect the erythrocytes against oxidative damage induced by peroxyl radicals. To conclude, CMTI-SH scavenges reactive oxygen species yielding CMTI disulfide while GSH maintains CMTI-SH in the reduced state. This finding was also demonstrated by experiment with CMTI-disulfide to protect the erythrocytes against oxidative damage induced by peroxyl radicals. CMTI-SH would thus represent the first line of the cellular defense against peroxyl radical mediated oxidative stress.

Cemtirestat inhibited lipid peroxidation more efficiently than GSHCemtirestat disulfide was proved as the main oxidation productCemtirestat disulfide protected erythrocytes against oxidative damageCemtirestat disulfide was readily reduced by GSHMechanism of thiol-disulfide exchange reaction was suggested.

Interaction of Thiol Antioxidants with α,ß-Unsaturated Ketone Moiety: Its Implication for Stability and Bioactivity of Curcuminoids.

Many biological functions of curcumin have been reported. As certain bioactivities of curcumin are eliminated by antioxidants, reactive oxygen species generated by curcumin have been suggested as a relevant mechanism. In the present study, the effects of different types of antioxidants on the stability and bioactivities of curcumin were analyzed. High concentrations (>4 mM) of thiol antioxidants, including N-acetylcysteine (NAC), glutathione (GSH), and ß-mercaptoethanol, accelerated the decomposition of curcumin and other curcuminoids; the submillimolar levels (<0.5 mM) of GSH and NAC rather improved their stability. Ascorbic acid or superoxide dismutase also stabilized curcumin, regardless of their concentration. The cellular levels and bioactivities of curcumin, including its cytotoxicity and the induction of heme oxygenase-1, were significantly reduced in the presence of 8 mM of GSH and NAC. The effects were enhanced in the presence of submillilmolar GSH and NAC, or non-thiol antioxidants. The present results indicate that antioxidants with a reduced thiol group could directly interact with the α,ß-unsaturated carbonyl moiety of curcuminoids and modulate their stability and bioactivity.

The neutrophil oxidant hypothiocyanous acid causes a thiol-specific stress response and an oxidative shift of the bacillithiol redox potential in Staphylococcus aureus.

IMPORTANCE: Staphylococcus aureus colonizes the skin and the airways but can also lead to life-threatening systemic and chronic infections. During colonization and phagocytosis by immune cells, S. aureus encounters the thiol-reactive oxidant HOSCN. The understanding of the adaptation mechanisms of S. aureus toward HOSCN stress is important to identify novel drug targets to combat multi-resistant S. aureus isolates. As a defense mechanism, S. aureus uses the flavin disulfide reductase MerA, which functions as HOSCN reductase and protects against HOSCN stress. Moreover, MerA homologs have conserved functions in HOSCN detoxification in other bacteria, including intestinal and respiratory pathogens. In this work, we studied the comprehensive thiol-reactive mode of action of HOSCN and its effect on the reversible shift of the E BSH to discover new defense mechanisms against the neutrophil oxidant. These findings provide new leads for future drug design to fight the pathogen at the sites of colonization and infections.

Curcumin promotes apoptosis of human melanoma cells by caspase 3.

Cutaneous melanoma (CM) is a malignant neoplasm with a high metastatic rate that shows poor response to systemic treatments in patients with advanced stages. Recently, studies have highlighted the antineoplastic potential of natural compounds, such as polyphenols, in the adjuvant therapy context to treat CM. The objective of the present study was to evaluate the effect of different concentrations of curcumin (0.1-100 µM) on the metastatic CM cell line SK-MEL-28. The cells were treated for 6 and 24 h with different concentrations of curcumin. Cell viability was assessed by 3-(4,5-dimethyl-2thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and fluorescence microscopy. The apoptotic-inducing potential was detected by annexin V flow cytometry. The wound healing assay was used to verify cell migration after the curcumin exposition. The redox profile was evaluated by levels of the pro-oxidant markers reactive oxygen species (ROS) and Nitric oxide (NOx) and antioxidants of total thiols (PSH) and nonprotein thiols. The gene expression and enzymatic activity of caspase 3 were evaluated by reverse transcription-quantitative polymerase chain reaction and a sensitive fluorescence assay, respectively. Curcumin significantly decreased the cell viability of SK-MEL-28 cells at both exposure times. It also induced apoptosis at the highest concentration tested (p < .0001). SK-MEL-28 cell migration was inhibited by curcumin after treatment with 10 µM (p < .0001) and 100 µM (p < .0001) for 6 and 24 h (p = .0006 and p < .0001, respectively). Furthermore, curcumin significantly increased levels of ROS and NOx. Finally, curcumin was capable of increasing the gene expression at 10 µM (p = .0344) and 100 µM (p = .0067) and enzymatic activity at 10 µM (p = .0086) and 100 µM (p < .0001) of caspase 3 after 24 h. For the first time, we elucidated in our study that curcumin increases ROS levels, promoting oxidative stress that activates the caspase pathway and culminates in SK-MEL-28 metastatic CM cell death.

Remarkable Effects of a Rhenium(I)-diselenoether Drug on the Production of Cathepsins B and S by Macrophages and their Polarizations.

BACKGROUND/OBJECTIVE: Tumor-associated macrophages (TAMs) produce an excessive amount of cysteine proteases, and we aimed to study the effects of anticancer rhenium(I)-diselenoether (Re-diSe) on the production of cathepsins B and S by macrophages. We investigated the effect of Re-diSe on lipopolysaccharides (LPS) induced M1 macrophages, or by interleukin 6 (IL-6) induced M2 macrophages. METHODS: Non-stimulated or prestimulated murine Raw 264 or human THP-1 macrophages were exposed to increasing concentrations of the drug (5, 10, 20, 50 and 100 µM) and viability was assayed by the MTT assay. The amount of cysteine proteases was evaluated by ELISA tests, the number of M1 and M2 macrophages by the expression of CD80 or CD206 biomarkers. The binding of Re-diSe with GSH as a model thiol-containing protein was studied by mass spectrometry. RESULTS: A dose-dependent decrease in cathepsins B and S was observed in M1 macrophages. There was no effect in non-stimulated cells. The drug induced a dramatic dose-dependent increase in M1 expression in both cells, significantly decreased the M2 expression in Raw 264 and had no effect in non-stimulated macrophages. The binding of the Re atom with the thiols was clearly demonstrated. CONCLUSION: The increase in the number of M1 and a decrease in M2 macrophages treated by Re-diSe could be related to the decrease in cysteine proteases upon binding of their thiol residues with the Re atom.

Increased intracellular persulfide levels attenuate HlyU-mediated hemolysin transcriptional activation in Vibrio cholerae.

The vertebrate host's immune system and resident commensal bacteria deploy a range of highly reactive small molecules that provide a barrier against infections by microbial pathogens. Gut pathogens, such as Vibrio cholerae, sense and respond to these stressors by modulating the expression of exotoxins that are crucial for colonization. Here, we employ mass spectrometry-based profiling, metabolomics, expression assays, and biophysical approaches to show that transcriptional activation of the hemolysin gene hlyA in V. cholerae is regulated by intracellular forms of sulfur with sulfur-sulfur bonds, termed reactive sulfur species (RSS). We first present a comprehensive sequence similarity network analysis of the arsenic repressor superfamily of transcriptional regulators, where RSS and hydrogen peroxide sensors segregate into distinct clusters of sequences. We show that HlyU, transcriptional activator of hlyA in V. cholerae, belongs to the RSS-sensing cluster and readily reacts with organic persulfides, showing no reactivity or DNA dissociation following treatment with glutathione disulfide or hydrogen peroxide. Surprisingly, in V. cholerae cell cultures, both sulfide and peroxide treatment downregulate HlyU-dependent transcriptional activation of hlyA. However, RSS metabolite profiling shows that both sulfide and peroxide treatment raise the endogenous inorganic sulfide and disulfide levels to a similar extent, accounting for this crosstalk, and confirming that V. cholerae attenuates HlyU-mediated activation of hlyA in a specific response to intracellular RSS. These findings provide new evidence that gut pathogens may harness RSS-sensing as an evolutionary adaptation that allows them to overcome the gut inflammatory response by modulating the expression of exotoxins.

Inhibition of Cysteine Proteases via Thiol-Michael Addition Explains the Anti-SARS-CoV-2 and Bioactive Properties of Arteannuin B.

Artemisia annua is the plant that produces artemisinin, an endoperoxide-containing sesquiterpenoid used for the treatment of malaria. A. annua extracts, which contain other bioactive compounds, have been used to treat other diseases, including cancer and COVID-19, the disease caused by the virus SARS-CoV-2. In this study, a methyl ester derivative of arteannuin B was isolated when A. annua leaves were extracted with a 1:1 mixture of methanol and dichloromethane. This methyl ester was thought to be formed from the reaction between arteannuin B and the extracting solvent, which was supported by the fact that arteannuin B underwent 1,2-addition when it was dissolved in deuteromethanol. In contrast, in the presence of N-acetylcysteine methyl ester, a 1,4-addition (thiol-Michael reaction) occurred. Arteannuin B hindered the activity of the SARS CoV-2 main protease (nonstructural protein 5, NSP5), a cysteine protease, through time-dependent inhibition. The active site cysteine residue of NSP5 (cysteine-145) formed a covalent bond with arteannuin B as determined by mass spectrometry. In order to determine whether cysteine adduction by arteannuin B can inhibit the development of cancer cells, similar experiments were performed with caspase-8, the cysteine protease enzyme overexpressed in glioblastoma. Time-dependent inhibition and cysteine adduction assays suggested arteannuin B inhibits caspase-8 and adducts to the active site cysteine residue (cysteine-360), respectively. Overall, these results enhance our understanding of how A. annua possesses antiviral and cytotoxic activities.

Development of a fluorescent-labeled trapping reagent to evaluate the risk posed by acyl-CoA conjugates.

Although acyl-CoA conjugates are known to have higher reactivity than acyl glucuronides, few studies have been conducted to evaluate the risk of the conjugates. In the present study, we aimed to develop a trapping assay for acyl-CoA conjugates using trapping reagents we have developed previously. It was revealed that Cys-Dan, which has both a thiol and an amino group, was the most effective in forming stable adducts containing an amide bond after intramolecular acyl migration. Additionally, we also developed a hepatocyte-based trapping assay in the present study to overcome the shortcomings of liver microsomes. Although liver microsomes are commonly used as enzyme sources in trapping assays, they lack some of the enzymes required for drug metabolism and detoxification systems. In human hepatocytes, our three trapping reagents, CysGlu-Dan, Dap-Dan and Cys-Dan, captured CYP-dependent reactive metabolites, reactive acyl glucuronides, and reactive acyl-CoA conjugates, respectively. The work suggests that the trapping assay with the reagents in hepatocytes is useful to evaluate the risk of reactive metabolites in drug discovery.

Zataria multiflora and its constituent, carvacrol, counteract sepsis-induced aortic and cardiac toxicity in rat: Involvement of nitric oxide and oxidative stress.

BACKGROUND: Zataria multiflora and carvacrol showed various pharmacological properties including anti-inflammatory and anti-oxidant effects. However, up to now no studies have explored its potential benefits in ameliorating sepsis-induced aortic and cardiac injury. Thus, this study aimed to investigate the effects of Z. multiflora and carvacrol on nitric oxide (NO) and oxidative stress indicators in lipopolysaccharide (LPS)-induced aortic and cardiac injury. METHODS: Adult male Wistar rats were assigned to: Control, lipopolysaccharide (LPS) (1 mg/kg, intraperitoneal (i.p.)), and Z. multiflora hydro-ethanolic extract (ZME, 50-200 mg/kg, oral)- and carvacrol (25-100 mg/kg, oral)-treated groups. LPS was injected daily for 14 days. Treatment with ZME and carvacrol started 3 days before LPS administration and treatment continued during LPS administration. At the end of the study, the levels of malondialdehyde (MDA), NO, thiols, and antioxidant enzymes were evaluated. RESULTS: Our findings showed a significant reduction in the levels of superoxide dismutase (SOD), catalase (CAT), and thiols in the LPS group, which were restored by ZME and carvacrol. Furthermore, ZME and carvacrol decreased MDA and NO in cardiac and aortic tissues of LPS-injected rats. CONCLUSIONS: The results suggest protective effects of ZME and carvacrol on LPS-induced cardiovascular injury via improved redox hemostasis and attenuated NO production. However, additional studies are needed to elucidate the effects of ZME and its constituents on inflammatory responses mediated by LPS.

Histochemical, Immunohistochemical, and Biochemical Investigation of the Effect of Resveratrol on Testicular Damage Caused by Methotrexate (MTX).

Cancer is one of the world's major causes of death. The aim of this study is to examine the acute effects of resveratrol on testicular toxicity, oxidative stress, and apoptosis caused by MTX, which is widely used in the treatment of many diseases, especially cancer, histochemically, immunohistochemically, and biochemical methods using different parameters. A total of 32 Wistar albino male rats were randomly divided into 4 groups: control, resveratrol (RES), MTX, and MTX + RES, with 8 animals in each group. At the end of the experiment, tissue and blood samples were taken, and histochemical, immunohistochemical, and biochemical parameters were examined. In this study, where parameters were compared for the first time, total thiol (TT) and native thiol (NT) are the highest in the RES group, disulfide (DS), and ischemia-modified albumin (IMA) are the highest in the MTX group. Total oxidant status (TOS) and oxidative stress index (OSI) are the highest in the MTX group, and total antioxidant status (TAS) is the highest in the RES group. Separation and deterioration in the tunica albuginea, congestion and edema in the interstitial region, vacuolization in the seminiferous epithelium, and spermatogenic serial cells spilling into the lumen without completing their maturation were observed. When examined in terms of histochemical, immunohistochemical, and biochemical examinations, our study revealed that resveratrol has positive effects on methotrexate-induced acute testicular damage, oxidative stress, and apoptosis.

Biological interactions and attenuation of MPTP-induced toxicity in Drosophila melanogaster by Trans-astaxanthin.

Trans-astaxanthin (TA) is a carotenoid with amphipathic chemical structure found in yeast, and aquatic organisms. It is known to possess both antioxidative and anti-inflammatory properties. This study was carried out to investigate the ameliorative action of TA on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced toxicity in Drosophila melanogaster (Fruit fly). The flies were orally treated with TA (2.5 mg/10 g diet) and/or MPTP (500 µM) for 5 days. Thereafter, we evaluated selected biomarkers of locomotor deficits (acetylcholinesterase (AChE) and negative geotaxis), oxidative stress (hydrogen peroxide (H2O2), protein carbonyls (PC)), antioxidants (total thiols (T-SH), non-protein thiols, glutathione-S-transferase (GST) and catalase), and inflammation (nitric oxide (nitrite/nitrate) in the flies. Furthermore, we investigated molecular docking analysis of TA against Kelch-like ECH-associated protein 1 (Keap1)) of Homo sapiens and D. melanogaster. The results indicated that TA increased MPTP-induced decreased activities of AChE, GST, and catalase, as well as levels of non-protein thiols and T-SH compared with MPTP-treated flies (p < 0.05). Furthermore, TA attenuated inflammation, and improved locomotor deficit in the flies. The molecular docking data showed that TA had docking scores for binding both the Human and Drosophila Keap1, nearly closer to or higher than the standard inhibitor. The attenuating effects of TA against MPTP-induced toxicity could arise from its antioxidative and anti-inflammatory properties as well as its chemical structure.

Effect of Allium cepa extract on total and differential WBC, TP level, oxidant and antioxidant biomarkers, and lung pathology in ovalbumin-sensitized rats.

BACKGROUND: Previous studies have shown that Allium cepa (A. cepa) has relaxant and anti-inflammatory effects. In this research, A. cepa extract was examined for its prophylactic effect on lung inflammation and oxidative stress in sensitized rats. METHODS: Total and differential white blood cell (WBC) count in the blood, serum levels of oxidant and antioxidant biomarkers, total protein (TP) in bronchoalveolar lavage fluid (BALF), and lung pathology were investigated in control group (C), sensitized group (S), and sensitized groups treated with A. cepa and dexamethasone. RESULTS: Total and most differential WBC count, TP, NO2, NO3, MDA (malondialdehyde), and lung pathological scores were increased while lymphocytes, superoxide dismutase (SOD), catalase (CAT), and thiol were decreased in sensitized animals compared to controls (p < 0.01 to p < 0.001). Treatment with all concentrations of extract significantly improved total WBC, TP, NO2, NO3, interstitial fibrosis, and emphysema compared to the S group (p < 0.05 to p < 0.001). Two higher concentrations of the extract significantly decreased neutrophil and monocyte count, malondialdehyde, bleeding and epithelial damage but increased lymphocyte, CAT, and thiol compared to the S group (p < 0.05 to p < 0.001). Dexamethasone treatment also substantially improved most measured parameters (p < 0.05 to p < 0.001), but it did not change eosinophil percentage. It was proposed that A. cepa extract could affect lung inflammation and oxidative stress in sensitized rats.