Postmitochondrial Fraction Research Articles

Gallic Acid Attenuates Cardiovascular and Hematological Complications in Vincristine Treatment via Hydroxyl Radical Scavenging and Endogenous Antioxidant Stimulation in Male Wistar Rats

The menace of cancer and the nightmare of complications of cancer chemotherapy have driven researchers to explore simple but efficient combination therapy that includes antioxidants, in cancer therapy. The ability of gallic acid to correct the toxic complication of Vincristine was investigated. Twenty adult male rats of the Wistar strain were grouped into four, randomly, consisting of five rats each. The untreated control (group A) was given only distilled water, groups B and C 0.025 mg/kg Vincristine sulfate intraperitoneally once a week for two weeks. Group C rats were thereafter administered 100 mg/kg gallic acid daily by gastric gavage for 14 days. At 14 days, blood pressure and ECG were measured in the rats, then blood samples were obtained via the retrorbital venous plexus for determination of haematological parameters and plasma biochemistry. They were then euthanized through cervical dislocation, under ether anaesthesia, and liver, kidneys, heart, and brain samples were collected, weighed, and stored for determination of marker of oxidative stress in the post mitochondrial fractions of each organ. Results of the study showed that rats in group B had hypertension as evidenced by elevated diastolic and systolic as well as mean arterial pressure while QT interval and corrected QT were slightly elongated. They also had lowered RBC, WBC, and granulocyte counts. Markers of oxidative stress, GSH, and SOD were also depleted while H2O2 generation increased in this group, whereas all the observed anomalies were corrected in the group C rats that were administered both Vincristine and gallic acid. This study further showed that Vincristine, at normal recommended therapeutic dosage is toxic, causing anaemia, panleucopenia, and cardiovascular anomalies via oxidative stress and generation of hydroxyl radicals. These were however corrected by concurrent administration of gallic acid

Blood biomarkers in white stork (Ciconia ciconia) nestlings show different responses in several areas of Croatia.

White stork nestlings can provide quantitative data on the quality of the environment, as they are dependent on their parents that provide locally foraged food. Blood was sampled from the brachial vein (n = 109) and the sampling was performed in parallel with ringing during breeding season 2020 from five areas in eastern Croatia: Lonjsko polje, Jelas polje, Slavonski Brod-east, Podunavlje, and Donje Podravlje. In the present study, for the first time in Croatia, the following enzymatic biomarkers were assessed in white stork nestlings: activities of acetylcholinesterase (AChE), carboxylesterase (CES), glutathione S-transferase (GST), and glutathione reductase (GR), as well as nonenzymatic biomarkers: levels of glutathione (GSH) and reactive oxygen species (ROS). All endpoints were measured in two blood fractions: plasma and a postmitochondrial fraction (S9). Nestlings from Podunavlje and Donje Podravlje, areas known for intensive agriculture, showed lower AChE and CES activity when compared to the other investigated areas, indicating the presence of inhibitory xenobiotics. Higher oxidative stress was observed in Slavonski Brod-east, an area surrounded by metal and engineering industry, and Podunavlje compared to the other sampling areas. Hence, this study shows the impact of pollutants from the surrounding metal, petroleum, and agricultural industry might have on the biomarkers in white stork nestlings, which are often seen as early-warning signals.

Pesticide-Induced Alterations of Esterase and Antioxidant Enzymes of Aquatic Organisms <i>Oreochromis mossambicus</i> and <i>Xenopus laevis</i>

Pesticides are extensively utilized in modern farming to control pests and weeds, thereby ensuring high quality and quantity of crops. Aerial drifts and runoffs after rain transport these agrochemicals to aquatic bodies, where they adversely affect aquatic organisms. We carried out a study to assess the effects of carbaryl and dimethoate on esterase and antioxidant enzyme activities of tadpoles, adult frogs and juvenile fish. These organisms were exposed to sublethal contraptions of 2.9 ppm carbaryl and 4.8 ppm dimethoate for 96 hours. After the exposure period, the fish and frogs were sacrificed and post-mitochondrial fractions were prepared for enzymatic analysis. Acetylcholinesterase (AChE), carboxylesterase (CbE), superoxide dismutase, glutathione peroxidase and catalase were measured. Carbaryl and dimethoate inhibited the activities of acetylcholinesterase, carboxylesterase, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in juvenile fish, tadpoles and adult frogs. Inhibition of SOD, CAT and GPx suggests that the two pesticides caused oxidative stress in the aquatic organisms, while inhibition of AChE and CbE affected the normal transmission of nerve impulses. The results indicate that the two pesticides affect the well-being of the studied aquatic organisms.

Mitoquinol mesylate (MITOQ) attenuates diethyl nitrosamine-induced hepatocellular carcinoma through modulation of mitochondrial antioxidant defense systems.

Diethyl nitrosamine (DEN) induced cirrhosis-hepatocellular carcinoma (HCC) model associates cancer progression with oxidative stress and mitochondrial dysfunction. This study investigated the effects of mitoquinol mesylate (MitoQ), a mitochondrial-targeted antioxidant on DEN-induced oxidative damage in HCC Wistar rats. Fifty male Wistar rats were randomly divided into five groups. Healthy control, DEN, and MitoQ groups were orally administered exactly 10mg/kgof distilled water, DEN, and MitoQ, respectively for 16weeks. Animals in the MitoQ + DEN group were pre-treated with MitoQ for a week followed by co-administration of 10mg/kg each of MitoQ and DEN. DEN + MitoQ group received DEN for 8weeks, then co-administration of 10mg/kg each of DEN and MitoQ till the end of 16th week. Survival index, tumour incidence, hematological profile, liver function indices, lipid profile, mitochondrial membrane composition, mitochondrial respiratory enzymes, and antioxidant defense status in both mitochondrial and post-mitochondrial fractions plus expression of antioxidant genes were assessed. In MitoQ + DEN and DEN + MitoQ groups, 80% survival occurred while tumour incidence decreased by 60% and 40% respectively, compared to the DEN-only treated group. Similarly, MitoQ-administered groups showed a significant (p<0.05) decrease in the activities of liver function enzymes while hemoglobin concentration, red blood cell count, and packed cell volume were significantly elevated compared to the DEN-only treated group. Administration of MitoQ to the DEN-intoxicated groups successfully enhanced the activities of mitochondrial F1F0-ATPase and succinate dehydrogenase; and up-regulated the expression and activities of SOD2, CAT, and GPx1. Macroscopic and microscopic features indicated a reversal of DEN-induced hepatocellular degeneration in the MitoQ + DEN and DEN + MitoQ groups. These data revealed that MitoQ intervention attenuated DEN-induced oxidative stress through modulation of mitochondrial antioxidant defense systems and alleviated the burden of HCC as a chemotherapeutic agent.

Comprehending the role of homeopathic preparations of Rauwolfia serpentina on oxidative stress parameters of cardiac tissue of DOCA-salt induced hypertensive male rats: An experimental approach

BackgroundOxidative stress has been associated in various pathophysiology of heart including hypertension, a global concern. The present work reports the effect of oral administration of different potencies of homeopathic preparations of R. serpentina (Q, 30c and 6c) on oxidative stress parameters of the ventricular cardiac tissue of hypertensive male rats. MethodHypertension was induced in unilaterally nephrectomized male rats by injecting DOCA (25 mg/kg BW) twice in a week and 1% NaCl in drinking water. Hypertensive rats were treated with different potencies of R. serpentina (Q, 30c and 6c) orally twice a day for 30 days. Oxidative stress parameters (lipid peroxidation and protein carbonyl content) and activities of enzymatic antioxidants, superoxide dismutase, catalase, glutathione erpentine, glutathione reductase and glutathione S-transferase were measured in cardiac tissue. Transcript and translate level of SOD1, SOD2, CAT and transcript level of GPx and GR were analysed in cardiac tissue. ResultsThe enhanced oxidative stress parameters in post mitochondrial (PMF) and mitochondrial fractions (MF) of ventricular tissue were reduced in response to Q, 30c and 6c of R. serpentina. Superoxide dismutase activity in PMF of ventricular tissue was elevated in response to Q of R. serpentina. The mRNA and translated products of SOD1 were elevated in response to Q and 30c of R. serpentina. Translated products of SOD2 were increased in PMF in response to Q and 30c treatment. A reduction in its level in MF was recorded in response to 30c. Catalase exhibits a dual response i.e. its activity was upregulated and downregulated, respectively, in the PMF and MF in response to drug treatment. Although glutathione peroxidase activity in the PMF of the ventricular tissue was decreased in response to 30c and 6c potencies, its activity in MF was elevated in response to 6c. ConclusionsResults suggest that homeopathic medicine R. serpentina reduces hypertension and associated oxidative stress in the cardiac tissue by modulating the antioxidant defence system.

Application of Non-Destructive Methods: Biomarker Assays in Blood of White Stork (Ciconia ciconia) Nestlings

Simple summaryProtocols were adjusted and established for biomarker assessment in two blood fractions: plasma and the post-mitochondrial fraction (S9). Basal biomarker values were determined in white stork (Ciconia ciconia) nestlings from Croatia, and biomarker responses in two different types of blood samples were compared. Novel fluorescence-based glutathione and reactive oxygen species detection was established providing the potential usage of blood for assessment of environmental impact at the molecular level.White stork (Ciconia ciconia) nestlings can provide quantitative information on the quality of the surrounding environment by indicating the presence of pollutants, as they depend on locally foraged food. This study represents the first comparison of biomarkers in two fractions of white stork nestling blood: plasma and S9 (the post-mitochondrial fraction). The aim of this study was to evaluate acetylcholinesterase (AChE), carboxylesterase (CES), glutathione S-transferase (GST), and glutathione reductase (GR), as well as to establish a novel fluorescence-based method for glutathione (GSH) and reactive oxygen species (ROS) detection in plasma and S9. Considering the enzymatic biomarkers, lower variability in plasma was detected only for AChE, as CES, GST, and GR had lower variability in S9. Enzyme activity was higher in plasma for AChE, CES, and GST, while GR had higher activity in S9. Regarding the fluorescence-based method, lower variability was detected in plasma for GSH and ROS, although higher GSH detection was reported in S9, and higher ROS was detected in plasma. The present study indicated valuable differences by successfully establishing protocols for biomarker measurement in plasma and S9 based on variability, enzyme activity, and fluorescence. For a better understanding of the environmental effects on nestlings’ physiological condition, biomarkers can be measured in plasma and S9.

The “Mix-Factor” is involved in the regulation of the organism's redox systems in the late stages of ontogenesis and affects the lifespan of animals

Abstract: the content of lipid hydroperoxides in the serum and liver mitochondria in animals in the late stages of ontogenesis (12 and 33 months old, Wistar male rats) was investigated. The possible effect of the food additive (“mix factor”) on these parameters in 33 months old animals, if they received this supplement from 22 months age daily throughout life in a dose of 0.05 - 0.06 ml / 100 g of body weight was determined. Moreover, the lifespan of animals was determined if they started taking a mix – factor from 22 months and from 30.5 months age. The influence of the mix – factor on the ability of old animals to perform work was determined in a separate series of experiments. It was shown that from 22 to 33 months the content of lipid hydroperoxides in mitochondria and serum increased by 23% and 41%, respectively. The activity of glutathione peroxidase in the serum, mitochondria and erythrocytes decreased, and the activity of glutathione reductase decreased only in the post-mitochondrial fraction of the liver. At the same time, malate– isocitrate dehydrogenase and 6-phosphate dehydrogenase remained unchanged in 33 months old animals compared with 12 months old animals. If animals from 22 months age received a mix factor with drinking water in a dose of 0.05-0.06 mg / 100 g of body weight every day until the end of life, the content of lipid hydroperoxides and the activity of glutathione peroxidase and glutathione reductase of 33 months old animals did not differ from 12 months old animals. The survival curve in animals receiving the mix factor was shifted to the right from 25 to 28 months of age compared with the survival curve of control animals. If animals began to receive the mix – factor at a very old age (from 30.5 months age) until the end of life, their lifespan was longer than that of the control animals. The last ones lived to 41 months, while the animals of the control group lived to 36 months. At the same time, the mix – factor increased the ability of old animals to do work in the test “running in treadmill”. Key words: aging, redox-system, geroprotectors, lifespan

In vitro metabolism of lidocaine in subcellular post-mitochondrial fractions and precision cut slices from cattle liver

In vitro models are widely used to study the biotransformation of xenobiotics and to provide input parameters to physiologically based kinetic models required to predict the kinetic behavior in vivo. For farm animals this is not common practice yet. The use of slaughterhouse-derived tissue material may provide opportunities to study biotransformation reactions in farm animals. The goal of the present study was to explore the potential of slaughterhouse-derived bovine liver S9 (S9) and precision cut liver slices (PCLSs) to capture observed biotransformation reactions of lidocaine in cows. The in vitro data obtained with both S9 and PCLSs confirm in vivo findings that 2,6-dimethylaniline (DMA) is an important metabolite of lidocaine in cows, being for both PCLSs and S9 the end-product. In case of S9, also conversion of lidocaine to lidocaine-N-oxide and monoethylglycinexylidine (MEXG) was observed. MEGX is considered as intermediate for DMA formation, given that this metabolite was metabolized to DMA by both PLCSs and S9. In contrast to in vivo, no in vitro conversion of DMA to 4-OH-DMA was observed. Further work is needed to explain this lack of conversion and to further evaluate the use of slaughterhouse-derived tissue materials to predict the biotransformation of xenobiotics in farm animals.

Comparative Proteomics Analysis of the Post‐Mitochondrial Fraction (S9 Fraction) of Human Lens‐Free Whole Eye and Liver

Background The increasing incidence of ocular diseases has accelerated research into therapeutic interventions for the eye. The knowledge of key metabolic mechanisms in the eye is vital for the successful ophthalmic drug discovery. The lens-free whole-eye post-mitochondrial fraction(S9 fraction) is one of the most widely used in vitro system for ocular metabolism studies during early drug discovery stage. As of now, no report of a comprehensive proteomics investigation exists for the pooled ocular S9 fraction. The objective of this study was to explore the human ocular S9 proteome and compare it with the human liver S9 proteome. Methods The global proteomics study was performed on the pooled ocular (n=11) and hepatic (n=50) S9 fraction samples in data-dependent acquisition mode using an optimized protocol. The samples were acquired in triplicate to minimize the technical variability. The acquired proteomics data were analyzed using Maxquant with 1% false discovery rate. A FASTA file containing whole human proteome, was used as the reference sequence for the search in the Andromeda database search tool. Additionally, another FASTA file containing 1187 proteins involved in the metabolism of endobiotics and xenobiotics was also searched to specifically identify the metabolic enzymes in both organs. The proteins were quantified using a generic label free quantification method (MaxLFQ) in Maxquant software. The metabolic enzymes common to both eye and liver S9 fractions were compared to determine the relative abundance values based on the resulting MaxLFQ intensities. The cut off for the differentially expressed proteins between the eye or liver was either <0.5 or >2. Results and Conclusion A total of 269 proteins (including 23 metabolic enzymes) were detected exclusively in the pooled eye S9, against 648 proteins in the liver S9 (including 174 metabolic enzymes), whereas 424 proteins (including 94 metabolic enzymes) were detected in both the organs. Among the common metabolic enzymes, 18 were predominant in the eye (Figure 1), 43 were predominant in the liver, while rest 33 were comparable in both samples. The major DMEs, viz., Cytochrome P450s, UDP-glucuronosyltransferases, and sulfotransferases, were not detected in the eye S9 fraction, instead isoforms of alcohol dehydrogenases, aldehyde dehydrogenases, carbonic anhydrases, aldo-keto reductases, esterases, epoxide hydrolases, and glutathione S-transferases were in abundance. This information bears great significance in gaining deeper insights on metabolic and bioactivation potential of both systemically as well as topically administered ophthalmic drugs as well as in the endobiotics metabolism within the eye. This investigation provides foundation for the subsequent targeted proteomic, genomic, and functional studies to explore the effects of sex, age, genotype and disease conditions across the populations.

Evaluación preliminar de biomarcadores enzimáticos en caracoles de agua dulce ( Pachychilus sp.) del humedal “Ciénaga de Tamasopo”, México

The activity of the enzymeacetylcholinesterase (AChE), the rate of conjugation of glutathione s-transferase (GST) and the presence of malondialdehyde (MDA), as biomarkers of exposure to pesticides, were determined during two seasons (dry and post-rains) in tissue of aquatic macroinvertebrates (freshwater snails - Pachychilus sp.-) residents of the “Cienega de Tamasopo” wetland (San Luis Potosi, Mexico). This was accompanied by a monitoring of the physicochemical parameters in the water of the wetland with a multiparameter probe. The activity of the biomarkers was determined in the S12 fraction (post-mitochondrial fraction) of tissues of Pachychilus sp. by means of UV-Visible spectrophotometry methods in a microplate reader. We found a lower activity of AChE (39.0%), higher ratio of conjugation of GST (28.5%) followed by a lower presence (25.0%) of lipid peroxidation (MDA) in the dry season in the tissue of the snails. In addition, significant associations were found between the ratio of conjugation of the GST with the rest of the biomarkers in both seasons, which is the result of detoxification processes in the snails. The activity of the biomarkers could be modulated by salinity, thus regulating the production of antioxidant enzymes and the toxicity of the pesticides used in agricultural areas near this wetland. The snails of the genus Pachychilus sp. they can be used as bioindicators of the health status of wetlands, which can lead to the design of management measures for the conservation and sustainable management of these ecosystems.

Cerium oxide nanoparticles and metformin increase the reliability of the prooxidant/antioxidant balance and the survival of ageing rats

In comparison with the action of metformin — mimetic of the calorie restricted diet, which prolong the animals lifespan, it has been studied the effect of nanoparticles of cerium dioxide (CeO2 NPs (1-2 nm)) on survival, physiological indices (the concentration of thyroxine, rectal temperature), as well as biochemical indices (content of lipid hydroperoxides, aconitase, glutathione peroxidase, glutaredoxin, glutathione reductase, NADP+ -dehydrogenase activities (glucose-6-phosphate-, malate- and isocitrate dehydrogenase)) in serum, liver mitochondrial and postmitochondrial fraction of ageing rats. It has been found that the prolonged use of CeO2 NPs with drinking water (0.25-0.30 mg/kg of body weight per day) and metformin (100-110 mg/kg of body weight per day) from 670 days after the birth lead to a significant increase in survival (the median survival of control rats was 900, in animals treated with CeO2 NPs — 960, and metformin — 990 days), a decrease in rectal temperature, a slowdown in the decrease in the level of thyroxine in blood, and normalization of the prooxidant/antioxidant balance in liver and blood tissues. Calculated integral index of reliability of prooxidant-antioxidant balance (reliability coefficient) in the studied tissues of rats in response to the application of the CeO2 NPs increased 4.99 times, and metformin — 4.94 times compared to intact animals. The data obtained allow us concluding about the prospects of the CeO2 NPs, as well as metformin for the development of geroprotector drugs, increasing the healthspan and survival of an ageing organism.

The geometry of the toxicity of silver nanoparticles to freshwater mussels

The question about the influence of the geometry of silver nanoparticle (nAg) towards toxicity in aquatic organisms is largely unanswered. The purpose of this study was to examine if different geometries of nAg could initiate biophysical stress in the soft tissues of mussels. Freshwater Dreissenna bugensis mussels were exposed for 48 h at 15 °C to 10 and 50 μg/L of ionic Ag and to 3 forms of polyvinylpyrrolidone (PVP)-coated nAg of similar size: sphere, cube and prism. At the end of the exposure period, mussels were allowed to depurate overnight and the post-mitochondrial fraction of the soft tissues were analyzed for the levels of liquid crystals (LCs), changes in the activity and fractal dimensions of pyruvate kinase-lactate dehydrogenase (PK-LDH), F-actin and protein-ubiquitin (UB) levels. The data revealed that exposure to nAg forms lead to increased formation of LCs in increasing order of intensity: prismatic > cubic > spherical nAg. The activity in PK-LDH was decreased by all forms of nAg but not by ionic Ag+ (as with the following effects). Fractal kinetics of the PK-LDH system revealed that the nAg forms increased the spectral dimension (sD) in increasing order: spherical > cubic > prismatic nAg. A decrease in the fractal diffusion rate (fDR) with small changes in the fractal dimension (fD) was also obtained. The levels of F-actin and protein-UB were significantly affected for most forms of nAg and followed a pattern similar to LCs levels. In conclusion, the geometry of nAg could influence the formation of LCs, alter the fractal kinetics of the PK-LDH system, F-actin levels and protein damage in the soft tissues of freshwater mussels.

KURKUMİN UYGULAMASININ YÜKSEK YAĞLI DİYETLE BESLENEN SIÇANLARIN TESTİS DOKUSUNDA OKSİDANANTİOKSİDAN SİSTEM ÜZERİNE ETKİSİ

Objective: High fat diet (HFD) induced oxidative stress is known to adversely affect testicular functions. Curcumin, which is an active ingredient of turmeric spice, has been shown to reduce lipid peroxidation and stimulate cellular antioxidant enzymes. The aim of this study is to investigate the effect of dietary curcumin on the testicular oxidant-antioxidant status in rats fed on a HFD. Material and Method: Male Sprague-Dawley rats were divided into four groups. Group 1 was fed with a control diet (10% of total calories from fat). Group 2 was fed with a HFD (60% of total calories from fat). Groups 3 and 4 received a HFD and a control diet with curcumin (1g/kg diet; w/w) respectively for 16 weeks. The testis tissue was homogenized and divided into postmitochondrial and mitochondrial fractions and the reactive oxygen species (ROS) levels were measured with the fluorometric method. The malondialdehyde (MDA) and glutathione (GSH) levels and glutathione peroxidase (GPx), superoxide dismutase (SOD) and glutathione transferase (GST) activities were measured with spectrophotometric methods. Results: HFD supplementation increased postmitochondrial and mitochondrial MDA levels and decreased cytosolic GSH levels in testis. MDA levels decreased with curcumin supplementation. Moreover, GSH levels and GST activity increased.&nbsp;However, curcumin supplementation alone did not affect oxidant-antioxidant status. ROS levels, SOD and GPx activities did not change significantly between the groups. Conclusion: Our data has shown that curcumin supplementation with HFD may prevent testicular oxidant damage. However, further studies are needed to investigate the underlying molecular mechanisms.&nbsp;

Age-Related Effects of Orthovanadate Nanoparticles Involve Activation of GSH-Dependent Antioxidant System in Liver Mitochondria.

Vanadium is an important ultra-trace element nowadays attracting attention with particular emphasis on medical application. But the therapeutic application of vanadium-based drugs is still questionable and restricted due to some toxic side effects. It was found that unique redox properties of vanadium in nanoform provided antioxidant activity and prevented oxidative disturbance in cells in vitro. Though, on the organism level, ambiguous effects of vanadium-based nanoparticles were observed. In this study, the age-related features of prooxidant/antioxidant balance in blood serum and liver mitochondrial and postmitochondrial fractions of 3 and 18-month-old Wistar male rats treated with orthovanadate nanoparticles (GdVO4/Eu3+, 8 × 25nm) within 2months have been investigated. Prooxidant potential-related indexes were the content of lipid hydroperoxides as well as aconitase activity. Activity of glutathione peroxidase, glutathione-S-transferase, glutaredoxin, glutathione reductase, glucose-6-phosphate dehydrogenase, and NADPH-dependent isocitrate dehydrogenase designated the tissue antioxidant potential. Based on the obtained values, the integral index of the prooxidant/antioxidant balance-the reliability coefficient (Kr) has been calculated. The data show that due to activation some chain links of GSH-dependent antioxidant system, GdVO4/Eu3+ nanoparticles increase the reliability of the prooxidant-antioxidant balance in tissues and especially in the liver mitochondria of old animals (Kr in mitochondria of young rats was 2.94, and in mitochondria of old ones-9.83 conventional units). Detected in vitro glutathione peroxidase-like activity of the GdVO4/Eu3+ nanoparticles is supposed to be among factors increasing the reliability of the system. So, for the first time, the beneficial effect of the long-term orthovanadate nanoparticle consumption in old males has been discovered.

Correlation of dicarboxylic acid cycle with tricarboxylic acid cycle in highly productive pigs

The paper is the fundamental beginning of research series aimed at understanding the processes associated with high performance in higher animals. The research aim is to study correlation of dicarboxylic acid cycle with tricarboxylic acid cycle with establishment of activity and dislocation of enzymes, confirming the hypothesis of availability and active metabolic participation of peroxisome in highly productive animals. Research was conducted on the basis of the VNIIFBiP animal vivarium in 2019 with a group of piglets of the Irish Landrace breed (n = 10). After slaughter at the age of 210 days, the nuclear (with large tissue particles), mitochondrial and postmitochondrial fractions of the liver were studied with assessment of succinate dehydrogenase and activity of other dehydrogenes of the Krebs cycle. It was found that peroxisomes act as universal agents of communication and cooperation, and microtelets are able to generate various chemical signals that carry information, to control and arrange a number of mechanisms in the metabolic processes in the body. Despite the fact that the Krebs cycle dehydrogenases are considered mitochondrial enzymes, the experiment showed an increase in activity of priruvate dehydrogenase (P &gt; 0.1), isocitrate dehydrogenase (0.1 &gt; P &gt; 0.05) and malate dehydrogenase (0.1 &gt; P &gt; 0.05), which, when comparing the mitochondrial and postmitochondrial fractions, indicates a higher activity of peroxisomal fractions. The peroxisome localization place is the postmitochondrial fraction, and the lower layer contains larger peroxisomes to a greater extent, while the upper layer contains smaller ones. It was found that indicator enzymes of glyoxylate cycle isocitratliase and malate synthase exhibit catalytic activity in the peroxisomal fraction of liver of highly productive pigs. The obtained data on functioning of key glyoxylate cycle enzymes and their intracellular compartmentalization in highly productive pigs allow learning more about the specifics of metabolism and its regulation processes. Application of this knowledge in practice opens up prospects for rationalizing the production of livestock products of increased quantity, improved quality with less feed, labor and financial resources spent.

Evaluación preliminar de biomarcadores enzimáticos en caracoles de agua dulce (&lt;i&gt;Pachychilus&lt;/i&gt; sp.) del humedal “Ciénaga de Tamasopo”, México

Se determinó la actividad de la enzima acetilcolinesterasa (AChE), el rango de conjugación de glutatión s-transferasa (GST) y la presencia de malondialdehído (MDA), como biomarcadores de exposición a plaguicidas, durante dos temporadas (secas y post-lluvias) en tejidos de macroinvertebrados acuáticos (caracoles de agua dulce -Pachychilus sp.-) residentes del humedal Ciénega de Tamasopo (San Luis Potosí, México). Esto se acompañó con un monitoreo de los parámetros fisicoquímicos en agua del humedal con una sonda multiparamétrica. La actividad de los biomarcadores se determinó en la fracción S12 (fracción post-mitocondrial) de tejidos de Pachychilus sp. mediante métodos de espectrofotometría UV-Visible en un lector de microplacas. Se encontró una menor actividad de AChE (39,0%) y un mayor rango de conjugación de GST (28,5%) seguido de una menor presencia (25,0%) de peroxidación lipídica (MDA) en la temporada de secas en el tejido de los caracoles. Además, se encontraron asociaciones significativas entre el rango de conjugación de GST con el resto los biomarcadores en ambas temporadas, lo cual es el resultado de procesos de desintoxicación en los caracoles. La actividad de los biomarcadores podría estar modulada por la salinidad regulando así la producción de enzimas antioxidantes y la toxicidad de los plaguicidas usados en las áreas agrícolas cercanas a este humedal. Los caracoles del género Pachychilus sp. pueden ser utilizados como como bioindicadores del estado de la salud de los humedales, lo cual puede derivar en el diseño de medidas de gestión para la conservación y manejo sustentable de estos ecosistemas.

Comparative effects of galactose-induced aging on mitochondrial permeability transition in rat liver and testis

This study investigated the status and sensitivity of mitochondrial permeability transition (mPT) pore in testis and liver of rats exposed to doses of galactose, an acceptable model used to mimic natural aging. Male albino rats were divided into five groups of eight animals in each group for in vivo studies and administered distilled water, 50,100, 200 and 500 mg galactose/kgbdwt, respectively, for six consecutive weeks. Mitochondria were isolated from liver and testis by differential centrifugation. Mitochondrial permeability transition (mPT) was assessed as mitochondrial swelling and was monitored spectrophotometrically. Mitochondrial lipid peroxidation, ATPase activity, antioxidant enzymes, caspase activation, interleukins, and sperm functional characteristics were also assessed. Administration of galactose (50–500 mg/kg) to male Wistar albino rats had no effect whatsoever on the testicular mPT pore. However, liver mPT pore was significantly opened. Furthermore, the enhancement of mitochondrial ATPase activity and malondialdehyde generation were observed in the liver of galactose-exposed rats. Significant alterations in antioxidant enzymes were observed in post-mitochondrial fraction (PMF) of liver and testis. There were also increases in serum levels of IL-1β and 6. In addition, caspases 9 and 3 were significantly elevated in PMF of the liver with evidence of DNA fragmentation. However, there was no significant difference in levels of caspases in PMF of testis in model groups of galactose when compared with control. These results provide evidence that testis mitochondria do not readily undergo permeability transition pore upon exposure to doses of D-galactose that induce the opening of the pore in the liver.HighlightsTesticular mitochondria are less sensitive to induction of permeability transition than liver mitochondria in rats exposed to D-galactose for 6 weeks, despite the occurrence of alterations in the antioxidant defense system and generation of ROS in sperm cells as in hepatocytes.The occurrence of mitochondrial permeability transition in liver of galactose-exposed rats is consistent with malondialdehyde production, alteration in antioxidant levels, enhanced ATPase activity, caspases-9 and 3 activation, immune dysfunction, and DNA fragmentation.The study of biochemical basis of reduced sensitivity of testis to permeability transition under conditions which the liver is extremely susceptible may become useful in age associated-neurodegenerative diseases where apoptosis is upregulated and has to be properly managed to achieve downregulation.

Dumped munitions: New insights into the metabolization of 2,4,6-trinitrotoluene in Baltic flatfish

Livers from dab (Limanda limanda), plaice (Pleuronectes platessa) and flounder (Platichthys flesus) sampled from the Baltic Sea were used to determine the interaction of flatfish CYP1A enzymes with 2,4,6-trinitrotoluene (TNT) in vitro. Competitive inhibition of 7-ethoxyresorufin-O-deethylase (EROD) and 7-methoxyresorufin-O-deethylase (MROD) could be demonstrated for all three flatfish species. The highest inhibition of CYP1A activities was measured in liver samples of flounder resulting in a half maximal inhibitory concentration (IC50) of 28.1 μM TNT. Due to their lower inhibition (EROD IC50 65.2 μM TNT, MROD IC50 40.3 μM TNT), dab liver samples were used to conduct in vitro metabolization experiments with TNT. The metabolization of TNT in fish was investigated with post-mitochondrial fractions (PMF) of dab liver as a model system after adding different cofactors. Rapid and time-dependent enzymatic degradation of TNT was observed. The concentrations of 4-amino-2,6-dinitrotoluene and 2-amino-4,6-dinitrotoluene increased in the samples over time. Additionally, 2,2,6,6-tetranitro-4,4-azoxytoluene was detected in one sample. The results of this study indicate that in vitro experiments are useful to investigate the xenobiotic metabolism of fish under controlled conditions prior to field studies. The metabolites found can serve as target compounds for marine monitoring of TNT contamination in munition dumpsites.

Oxidative stress in mitochondria of the brain tissue with aluminum neurotoxycosis and applying of glutathione and modulators of coenzyme A biosynthesis

Using an experimental model of aluminum neurotoxicosis, it was established that under conditions of chronic administration of aluminum chloride to rats, oxidative stress develops and inhibits the redox potential of the glutathione system in the mitochondrial and postmitochondrial fractions of the cerebral hemispheres. It was shown that the ingestion of N-acetylcysteine, as well as its combined use with coenzyme A biosynthesis precursors (D-panthenol or D-pantetin) against the background of aluminum neurotoxicosis, leads to a marked decrease in the production of reactive oxygen species by mitochondria, a decrease in the production of thiobarbituric acid reactive substances, and normalization of GSH content and its biosynthesis in brain tissue. The results indicate a high efficiency of the biosynthesis precursor of glutathione N-acetylcysteine in the prevention of oxidative stress in the chronic model of aluminum neurotoxicosis, which may be the rationale for its use as a modulator of mitochondrial redox status in the development of neurodegenerative pathology.

Detection, biophysical effects, and toxicity of polystyrene nanoparticles to the cnidarian Hydra attenuata.

The occurrence of nanoplastic particles (NPs) in the environment has raised concerns about the ecotoxicological risk to aquatic ecosystems. The purpose of this study was to examine the bioavailability and toxicity of 50- and 100-nm transparent polystyrene NPs to the cnidarian Hydra attenuata. The hydras were exposed to increasing concentrations of 50- and 100-nm NPs (1.25, 2.5, 5, 10, 20, 40, and 80mg/L) for 96h at 20°C followed by a 24-h depuration step. Hydras were analyzed for morphological changes, bioaccumulation of NPs using a novel assay for polystyrene NPs, oxidative stress (lipid peroxidation), polar lipids, lipid-like liquid crystals (LCs), and viscosity changes in the post-mitochondrial fraction. The results revealed that the organisms accumulated detectable amounts of NP in a concentration-dependent manner for both the 50- and 100-nm NP that persisted after 24h in clean media. Changes in morphology were observed with a 50% effect concentration of 3.6 and 18mg/L for the 50- and 100-nm-diameter NPs respectively. However, based on the particle concentration, the 100nm proved to be 1.7 times more toxic than the 50-nm NPs. Exposure to NPs led to decreased biomass, lipid peroxidation (LPO), increased polar lipid levels, viscosity, and formation of LCs at the intracellular level. In the more toxic NP (100nm), NPs in tissues were correlated with LCs, polar lipids, and LPO levels. It appears that the formation of organized LCs and polar lipids of NPs in cells was involved with NP toxicity and could represent a yet unidentified, detoxifying/bioactivation mechanism against colloidal plastics in cells. In conclusion, NPs are bioavailable to hydra and lead to LPO and lipid mobilization in hydra. The capacity of increasing lipid mobilization and LCs could determine the size-dependence toxicity of NPs.