Tissue Concentrations Research Articles

The effect of eight weeks of endurance training and MitoQ supplementation on antioxidant capacity and the expression of sestrin-2 and AMPK in cardiac tissue of aged rats

PurposeThe present study aimed to investigate the effects of endurance training (ET) in combination with MitoQ supplementation on antioxidant indices and the expression of sesterin-2 (SESN2) as an anti-aging factor and AMPK as an energy sensor in aged male Wistar rats. MethodsTwenty-eight aged Wistar rats (410 ± 15 g, 22 ± 1.5 months old) were randomly divided into four groups (n = 7): Control, ET (eight weeks endurance training on the treadmill), MitoQ (250 μ/L in drinking water), and ET + MitoQ. We measured the protein and gene expression of SESN2 and AMPK in the heart tissue by western blotting and real-time PCR, respectively. In addition, antioxidant indices, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activity, and oxidant malondialdehyde (MDA) concentration in the cardiac tissue and serum were measured. ResultsSESN2 and AMPK protein expression significantly increased in the MitoQ group compared to the control group (P = 0.002, P = 0.0003). MDA content in tissue and serum remained unchanged in all groups (P > 0.05). MitoQ supplementation significantly increased SOD and GPx enzyme activity in serum and cardiac tissue (P = 0.001). ConclusionOverall, ET and MitoQ alone and in combination have anti-aging effects and improve the expression of AMPK and SESN2. Additionally, ET and MitoQ lead to improved antioxidant capacity in aged rats by ameliorating the activity of antioxidant enzymes.

Asiatic acid mitigates testosterone-induced benign prostatic hyperplasia in rats via activation of PPAR-γ.

Prostate enlargement due to benign prostate hyperplasia (BPH) is a common, progressive disorder in elderly males with increasing prevalence. It causes devastating lower urinary tract symptoms with no satisfactory medication. Asiatic acid (AA), a natural pentacyclic triterpenoid, is known to have antiproliferative, antioxidant, and anti-inflammatory activities. The aim of this study was to evaluate the possible preventive activities of AA against BPH induced by testosterone in rats. Finasteride (0.5 mg/kg) was used as a reference drug. AA (10 or 20 mg/kg) administration inhibited the rise in prostatic weight and index induced by testosterone. Histopathological staining proved that AA mitigated the pathological features of BPH induced by testosterone, which was reflected as lower glandular epithelial in AA-treated groups. Also, the administration of AA along with testosterone restored the redox valance by inhibiting lipid peroxidation, and MDA production, and restoring the activities of superoxide dismutase (SOD) and catalase (CAT) activities. Also, AA reduced prostate interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-α), and nuclear factor-kappa B (NF-κB) protein expression. In addition, AA modulated mRNA expression of Bax and Bcl-2 in favor of apoptosis. The effects of AA (20 mg/kg) were comparable to those of finasteride. Further, AA ameliorated the rise in insulin-like growth factor 1 receptor (IGF-1R) mRNA expression. This was associated with the enhancement of the prostatic content of PPAR-γ. It can be concluded that AA mitigated the features of BPH induced by testosterone in rats. This involves antioxidant, anti-inflammatory and pro-apototic activities of AA as well as its ability to down-regulate IGF-1R expression and enhance PPAR-γ concentration in prostatic tissues.

The Potential of Transforming Growth Factor-Beta1 (TGFβ1) in Fibrotic Tissue of Leiomyoma Specimens

Background: Fibrosis can define as the development of excessive fibrous tissue in an organ or tissue. In the situation of the uterus, leiomyoma or scar tissue may involve fibrosis state. The main feature of fibrosis in myoma is the existence of disordered smooth muscle cells and collagen that can be recognized via histological examinations in addition to extracellular component deposition. Leiomyoma is the most public uterine disorder that is mainly consists of smooth muscle cells, myo-fibroblast, and an obvious content of extracellular matrix. The myofibroblast in myoma lesion produced an elevated content of ECM. This paper displays the fibrotic circumstantial in leiomyoma and the mechanisms related to deposition of ECM components. Methods: this study involved (50) patients of 18-80 years old women diagnosed with benign uterine fibroid. Tumor samples were attained by consent from women undergoing hysterectomy or myomectomy at the Al Karama Teaching Hospitals in Kut, Wasit Province, Iraq between October 2022 to March 2023. samples from normal and fibroid were subjected to routein histological processing and subsequently stained with routein stains for general description, Masson Trichrome stain, Van Gieson's stain to visualize collagen content and histochemical stain (Alcian Blue-Periodic Acid Schiff) to evaluate the profile of mucins secreted via tumor cells.Normal myometrium and myoma tissue expression of TGF β1 growth factor was compared using immunohistochemical staining. Qupath and Image J programs were used to analysis the content of fibrous tissue within normal and myoma tissue. Results: Microscopical results revealed that myoma have a proliferation of overlap fusiform cells organized in bundles alienated by variable amounts of connective tissue fibers, enclosed peripherally by a pseudo capsule. Special stained sections analysis revealed deposition of extracellular martix components specially collagen fibers that vary within each nodular fibroid (intrafascicular, interfascicular) enclosed myocytes that reflect the state of fibrosis that appears as blue – green colors enclosed in Masson's trichrome stain, while in Van Gieson's stain appears as red color. Proliferative tumor cells were revealed via Alcian Blue-PAS stain in dark blue color. results showed distribution of perivascular fibers in myoma as compared with normal adjacent myometrium, which appears in red color in Van Gieson's stain. Immunostaining recorded the significantly higher intensity of TGF-β in the leiomyoma tissue than in the normal myometrium (P < 0.05). The effects of the TGF-β1 inhibitor significantly differed between normal myometrium and leiomyoma tissue, with a greater decrease in cell survival in the leiomyoma tissue (P < 0.05). Conclusion: highly fibrous tissue contents showed within myoma and perivascular than adjacent myometrium, these fibrous tissues were detected via special colours in both Masson Trichrome and Van Gieson's stains. The fibrous tissue within leiomyoma showed higher intensity to TGF than normal myometrium.

General In Situ Engineering of Carbon-Based Materials on Carbon Fiber for In Vivo Neurochemical Sensing.

Developing real-time, dynamic, and in situ analytical methods with high spatial and temporal resolutions is crucial for exploring biochemical processes in the brain. Although in vivo electrochemical methods based on carbon fiber (CF) microelectrodes are effective in monitoring neurochemical dynamics during physiological and pathological processes, complex post modification hinders large-scale productions and widespread neuroscience applications. Herein, we develop a general strategy for the in situ engineering of carbon-based materials to mass-produce functional CFs by introducing polydopamine to anchor zeolitic imidazolate frameworks as precursors, followed by one-step pyrolysis. This strategy demonstrates exceptional universality and design flexibility, overcoming complex post-modification procedures and avoiding the delamination of the modification layer. This simplifies the fabrication and integration of functional CF-based microelectrodes. Moreover, we design highly stable and selective H+, O2, and ascorbate microsensors and monitor the influence of CO2 exposure on the O2 content of the cerebral tissue during physiological and ischemia-reperfusion pathological processes.

Assessing the Influence of Urine pH on the Efficacy of Ciprofloxacin and Fosfomycin in Immunocompetent and Immunocompromised Murine Models of Escherichia coli and Klebsiella pneumoniae Infection in the Lower Urinary Tract.

In vitro studies have suggested that acidic pH may reduce and increase the efficacy of ciprofloxacin and fosfomycin, respectively, when used to treat Escherichia coli and Klebsiella pneumoniae infections. We assessed the effects of acidic, neutral, and alkaline urine pH on the efficacy of optimized ciprofloxacin and fosfomycin dosages in UTI murine model of E. coli and K. pneumoniae. Immunocompetent and immunocompromised mice with adjusted urine pH were inoculated with E. coli and K. pneumoniae strains, and the efficacy was assessed based on the bacterial concentrations in tissues and fluids at 72 h, with respect to untreated controls. At acidic urine pH, both antimicrobials were effective, achieving similar reductions in E. coli concentrations in the kidneys in immunocompetent and immunocompromised mice and in K. pneumoniae in immunocompetent mice. At a neutral urine pH, both therapies reduced the presence of E. coli in the kidneys of immunocompetent mice. However, in immunocompromised mice, antimicrobials were ineffective at treating E. coli infection in the kidneys at a neutral urine pH and showed reduced efficacy against K. pneumoniae at both acidic and neutral urine pH. The results showed no correlation between urine pH and antimicrobial efficacy, suggesting that the reduced effectiveness is associated with the animals' immunocompetence status.

361. PHOTODYNAMIC THERAPY IN THE TREATMENT OF ESOPHAGEAL MUCOSAL METAPLASIA IN CHILDREN

Abstract Background The urgency of the problem of gastroesophageal reflux disease (GERD) in pediatrics is due to the high prevalence of this pathology in children. The problem of GERD in childhood has become especially important, when a direct correlation between the duration of esophagitis and the development of Barrett's esophagus (BE) and, later, esophageal adenocarcinoma has been revealed. Photodynamic therapy (PDT) is used as one of the elements of complex treatment after antireflux surgeries for direct impact on metaplastic mucosa and restoration of normal esophageal lumen. Due to the increased detection of esophageal malignancies in adult patients, we aimed to investigate this method in the treatment of Barrett's esophagus in children. Methods There were 3 patients diagnosed with esophageal mucosal metaplasia in the thoracic surgery department. Intestinal esophageal metaplasia was detected and histologically confirmed in 1 patient, in 2 patients - gastric metaplasia of cardiac type. All patients were female. The average age of the patients was 15 years. Children underwent multiple sessions of balloon dilatation of esophageal stenosis with temporary positive effect. Taking into account persistent restenosis, presence of metaplasia areas we applied PDT. Intravenous injection of photosensitizer (PS) of chlorine series for 30 minutes was carried out 5 hours before the beginning of PDT. For PDT we used a laser unit with a wavelength of 662 nm, power of 1 W with exposure of 25-30 minutes (at the rate of 300 J/cm2), optical power meter, video gastroscope, spectroanalyzer. Results To achieve the result: complete destruction of metaplasia sites and recanalization of the esophageal lumen, 1 patient with intestinal metaplasia needed 3 sessions, 2 patients with gastric metaplasia of cardiac type - 4 sessions of PDT. In children with gastric metaplasia, an "initiation" method was developed and applied at first PDT session to induce inflammation in the esophageal mucosa. During PDT macroscopic changes of mucosa in the metaplasia area were registered: ischemia, edema and hyperemia, hemorrhagic manifestations, "parchment" mucosa. We were also focused on the amount of PS in tissues according to the graphic images of the spectroanalyzer. During control examinations we noted healing of the metaplasia zone with subsequent regeneration of the epithelium, which was confirmed histologically, and preservation of the normal esophageal lumen. Conclusion Thus, there is a possibility of effective use of photodynamic therapy for esophageal mucosal metaplasia in children and adolescents. Taking into account the minimally invasive technique, comparative cheapness of photosensitizers, equipment for generation of laser radiation, registration of photosensitizer concentration in tissues, it is possible to create the basis for conducting studies in the treatment of this pathology in children. The method of photodynamic therapy in Barrett's esophagus demonstrates high efficiency in its eradication. Increasing the number of observations will allow to make more meaningful conclusions in the future. Eradication of Barrett's esophagus in children meets the requirements of cancer vigilance.

Matairesinol blunts adverse cardiac remodeling and heart failure induced by pressure overload by regulating Prdx1 and PI3K/AKT/FOXO1 signaling

BackgroundPathological cardiac remodeling is a critical process leading to heart failure, characterized primarily by inflammation and apoptosis. Matairesinol (Mat), a key chemical component of Podocarpus macrophyllus resin, exhibits a wide range of pharmacological activities, including anti-hydatid, antioxidant, antitumor, and anti-inflammatory effects. PurposeThis study aims to investigate whether Matairesinol alleviate cardiac hypertrophy and remodeling caused by pressure overload and to elucidate its mechanism of action. MethodsAn in vitro pressure loading model was established using neonatal rat cardiomyocytes treated with angiotensin Ⅱ, while an in vivo model was created using C57 mice subjected to transverse aortic constriction (TAC). To activate the PI3K/Akt/FoxO1 pathway, Ys-49 was employed. Moreover, small interfering RNA (siRNA) and short hairpin RNA (shRNA) were utilized to silence Prdx1 expression both in vitro and in vivo. Various techniques, including echocardiography, wheat germ agglutinin (WGA) staining, HE staining, PSR staining, and Masson trichrome staining, were used to assess cardiac function, cardiomyocyte cross-sectional area, and fibrosis levels in rats. Apoptosis in myocardial tissue and in vitro was detected by TUNEL assay, while reactive oxygen species (ROS) content in tissues and cells was measured using DHE staining. Furthermore, the affinity of Prdx1 with Mat and PI3K was analyzed using computer-simulated molecular docking. Western blotting and RT-PCR were utilized to evaluate Prdx1 levels and proteins related to apoptosis and oxidative stress, as well as the mRNA levels of cardiac hypertrophy and fibrosis-related indicators. ResultsMat significantly alleviated cardiac hypertrophy and fibrosis induced by TAC, preserved cardiac function, and markedly reduced cardiomyocyte apoptosis and oxidative damage. In vitro, mat attenuated ang Ⅱ - induced hypertrophy of nrvms and activation of neonatal rat fibroblasts. Notably, activation of the PI3K/Akt/FoxO1 pathway and downregulation of Prdx1 expression were observed in TAC mice; however, these effects were reversed by Mat treatment. Furthermore, Prdx1 knockdown activated the PI3K/Akt/FoxO1 pathway, leading to exacerbation of the disease. Molecular docking indicated that Molecular docking indicated that Mat upregulated Prdx1 expression by binding to it, thereby inhibiting the PI3K/Akt/FoxO1 pathway and protecting the heart by restoring Prdx1 expression levels. ConclusionMatairesinol alleviates pressure overload-induced cardiac remodeling both in vivo and in vitro by upregulating Prdx1 expression and inhibiting the PI3K/Akt/FoxO1 pathway. This study highlights the therapeutic potential of Matairesinol in the treatment of cardiac hypertrophy and remodeling, providing a promising avenue for future research and clinical application.

High temperature induces oxidative stress in spotted seabass (Lateolabrax maculatus) and leads to inflammation and apoptosis

Our study aims to examine the changes of long-term high temperature on the mortality and health status of spotted seabass (Lateolabrax maculatus), as well as to screen suitable biomarkers to determine whether the spotted seabass is under heat stress. In this study, 360 juvenile spotted seabass were evenly distributed into three temperature-controlled systems at 27°C (N, normal temperature), 31°C (M, moderate temperature), and 35°C (H, high temperature) for an 8-week aquaculture experiment. The results revealed that 35°C water temperature significantly increased the mortality and the MDA content in tissues (P < 0.05). Meanwhile, 35°C water temperature significantly increased the activity of SOD enzyme and T-AOC capacity in tissues, as well as the expression of hsp60, hsp70, and hsp90 (P < 0.05). Additionally, the expression of nrf2, il1β, il8, caspase3, caspase9, and bax in the liver significantly increased (P < 0.05), while the expression of keap1, il10, tgfβ, and bcl2 decreased significantly (P < 0.05). These results indicate that 35°C water temperature induces oxidative stress in spotted seabass, leading to tissue oxidative damage, promoting inflammation and apoptosis in liver, and increasing mortality. However, the organism compensates by heightening its antioxidant capacity via the Nrf2-Keap1 signaling pathway and inducing high expression of heat shock proteins for self-protection. Furthermore, the alterations in the mRNA level of hsp70 and MDA content in the liver, muscle, and kidney can serve as indicators for evaluating spotted seabass under prolonged heat stress.

PSXI-16 Increased copper concentrations in liver and duodenum tissues in Rambouillet-crossbred sheep receiving copper supplementation

PSXI-16 Increased copper concentrations in liver and duodenum tissues in Rambouillet-crossbred sheep receiving copper supplementation

Extract of Nanhaia speciosa J. Compton & Schrire alleviates LPS-induced acute lung injury via the NF-κB/Nrf2/AQPs pathway

Ethnopharmacological relevanceNanhaia speciosas J. Compton & Schrire (the name Nanhaia speciosas J. Compton & Schrire has been accepted by the World Checklist of Vascular Plants https://www.worldfloraonline.org/taxon/wfo-0001444004) is a traditional Zhuang medicine that have been widely used for centuries. It has been used in the treatment of lung inflammation, tuberculosis, rheumatic pain, lumbar muscle strain, and various other ailments, such as chronic hepatitis, menoxenia, leukorrhea, and injuries. In addition, N. speciosa has also been used to treat acute lung injury (ALI). Aim of the studyThe objective of this study was to conduct a comparative analysis of the effects of various constituents present in N. speciosas extract (NSE) on ALI and the related mechanisms while also elucidating the potential active monomeric components. Materials and methodsNSE was extracted using an AB-8 macroporous resin column, and five fractions (Fr. 0%, 25%, 50%, 75% and 95%) were obtained. The anti-inflammatory and antioxidant capacities of the five fractions were evaluated in an A549 cell-based in vitro model, with the aim of evaluating their potential therapeutic effects. The anti-inflammatory and antioxidant capacities of NSE were assessed in a murine model of ALI induced by intratracheal injection of LPS. We utilized an in vitro model to analyse the critical molecular mechanisms through which NSE ameliorates ALI. The chemical composition of the optimal fraction was analysed and confirmed using UHPLC/MS. ResultsDifferent fractions (especially Fr. 75%) significantly reduced inflammation and oxidative stress in A549 cells. Fr.75% abrogated LPS-induced pathological alterations and decreased the lung W/D ratio, total protein concentration in BALF, and the levels of the proinflammatory factors TNF-α, IL-6, and IL-1β. Moreover, Fr.75% reduced MPO and MDA concentrations and elevated SOD and GSH concentrations in pulmonary tissues. Additionally, it decreased the pulmonary tissue inflammation caused by LPS by downregulating the expression of p-NF-κB p65 and upregulating the expression of Nrf2, AQP1 and AQP5. Fr. 75% decreased p-NF-κB p65 protein levels; increased Keap1, Nrf2, HO-1, NQO1, AQP1 and AQP5 protein levels; and promoted the entry of Nrf2 into the nucleus. After UHPLC/MS analysis was conducted, the flavonoid Maackiain was determined to potentially play a pivotal role in this process. ConclusionFr.75% alleviates ALI by regulating the NF-κB/Nrf2/AQPs signalling pathway. The flavonoid Maackiain may also play an important role in this process. Overall, N. speciosas may be a potential therapeutic agent for the prevention and treatment of ALI.

Characterization of pediatric porcine pulmonary valves as a model for tissue engineered heart valves

Heart valve tissue engineering holds the potential to transform the surgical management of congenital heart defects affecting the pediatric pulmonary valve (PV) by offering a viable valve replacement. While aiming to recapitulate the native valve, the minimum requirement for tissue engineered heart valves (TEHVs) has historically been adequate mechanical function at implantation. However, long-term in situ functionality of TEHVs remains elusive, suggesting that a closer approximation of the native valve is required. The realization of biomimetic engineered pediatric PV is impeded by insufficient characterization of healthy pediatric tissue. In this study, we comprehensively characterized the planar biaxial tensile behaviour, extracellular matrix (ECM) composition and organization, and valvular interstitial cell (VIC) phenotypes of PVs from piglets to provide benchmarks for TEHVs. The piglet PV possessed an anisotropic and non-linear tension-strain profile from which material constants for a predictive constitutive model were derived. The ECM of the piglet PV possessed a trilayer organization populated by collagen, glycosaminoglycans, and elastin. Biochemical quantification of ECM content normalized to wet weight and DNA content of PV tissue revealed homogeneous distribution across sampled regions of the leaflet. Finally, VICs in the piglet PV were primarily quiescent vimentin-expressing fibroblasts, with a small proportion of activated α-smooth muscle actin-expressing myofibroblasts. Overall, piglet PV properties were consistent with those reported anecdotally for pediatric human PVs and distinct from those of adult porcine and human PVs, supporting the utility of the properties determined here to inform the design of tissue engineered pediatric PVs. Statement of significanceHeart valve tissue engineering has the potential to transform treatment for children born with defective pulmonary valves by providing living replacement tissue that can grow with the child. The design of tissue engineered heart valves is best informed by native valve properties, but native pediatric pulmonary valves have not been fully described to date. Here, we provide comprehensive characterization of the planar biaxial tensile behaviour, extracellular matrix composition and organization, and valvular interstitial cell phenotypes of pulmonary valves from piglets as a model for the native human pediatric valve. Together, these findings provide standards that inform engineered heart valve design towards generation of biomimetic pediatric pulmonary valves.

Real-time detection of cerebral edema in mice based on low-field nuclear magnetic resonance

Cerebral edema is a secondary symptom of several conditions, including stroke, liver, failure, and severe craniocerebral injury. This study aimed to propose a Low-Field Nuclear Magnetic Resonance (LF-NMR) method for rapid and nondestructive measurement of brain water content and water phase state evaluating animal brain edema models. The water transverse relaxation time (T2) distribution in brain tissues was ascertained by measuring the T2 spectrograms of mouse brain tissues following various drying durations, in accordance with the shifting law of T2 peaks. A methodological study was carried out for the determination of water content in mouse brain tissue by the LF-NMR Peak Area (LF-NMR-PA) method using CuSO4 solution as standard solution. This method was studied in comparison with the wet/dry weight method and the Partial Least Squares Regression (PLSR) prediction method in normal and MCAO model mice, and further applied to the study of mannitol treatment of cerebral edema to validate the precision and accuracy of the hydration measurements as well as the method’s impact on subsequent experiments of cerebral infarct area measurement. In the T2 spectra of mouse brain tissues, the separate peaks T21 (0–10 ms), T22 (10–100 ms), and T23 (100–1000 ms) correspond to fat and bound water, water, and free water in brain tissue, respectively. The LF-NMR-PA method had good specificity, linearity, precision, stability, reproducibility, and recovery. The accuracy and range of use of the LF-NMR-PA method were better than those of the PLSR method, and its results were not significantly different from those of the wet/dry weight method. However, the short measurement time of the LF-NMR-PA method ensured the integrity of the tissues, and the determination of the moisture by this method did not have a significant effect on the subsequent determination of the area of cerebral infarction, which ensured the consistency of the experimental results.

P164 SOLUBLE GUANYLATE CYCLASE STIMULATORS: AN EMERGING OPTION IN THE TREATMENT OF PRESSURE AND VOLUME OVERLOAD INDUCED CHRONIC HEART FAILURE

Pressure and volume overload-induced chronic heart failure (HF) is associated with characteristic cardiac remodeling and ventricular myocardial proteomic alterations, that can lead to the formation of a substrate for arrhythmias. Antiarrhythmic drug therapy is still suboptimal and current therapies are not efficacious enough. The purpose of the current study was therefore to examine the efficiency of nitric oxide (NO)/soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP) stimulator. We used as an experimental model male hypertensive Ren-2 transgenic rats (TGR) (n = 16), normotensive Hannover Sprague–Dawley rats (HSD, n = 17), and a volume-overload HF rat model induced by creating the aortocaval fistula (ACF) in rats of both strains (n = 27). Rats were after the induction of ACF treated by sGC stimulator BAY41-8543 (3 mg/kg/day for 30 weeks) alone or combined with angiotensin-converting enzyme inhibitor (ACEi) Trandolapril (0.25 mg/kg/day for 30 weeks). The age of the animals at the end of the experiment was 40 weeks. Left ventricle tissue and plasma samples were used for further analyses. Blood pressure (BP) was measured by telemetry. Combined treatment with sGC stimulator and ACEi was the most potent in lowering BP. Moreover, supplementation by sGC stimulator alone significantly decreased mortality and increased levels of the antioxidant enzyme superoxide dismutase 1, matrix metalloproteinase 2, total and phosphorylated connexin 43 as well as protein kinase C epsilon, implicated in remodeling of extracellular matrix and intercellular communication, in the left ventricle of TGR rats. Application of the sGC stimulator also slightly normalized elevated collagen deposition and hydroxyproline content in the left ventricular tissue of TGR rats. Unfortunately, we did not observe any effect of the sGC stimulator in the TGR ACF group. These results support the hypothesis that sGC stimulators might represent a class of drugs suitable for the prevention and treatment of related disorders in HF. This work was supported by APVV-21-0410, VEGA 2/0006/23, and EXCELES LX22NPO5104. Supported by APVV-21-0410, VEGA 2/0006/23, and EXCELES LX22NPO5104.

Anaesthetics disrupt complex I-linked respiration and reverse the ATP synthase

The mechanism of volatile general anaesthetics has long been a mystery. Anaesthetics have no structural motifs in common, beyond lipid solubility, yet all exert a similar effect. The fact that the inert gas xenon is an anaesthetic suggests their common mechanism might relate to physical rather than chemical properties. Electron transfer through chiral proteins can induce spin polarization. Recent work suggests that anaesthetics dissipate spin polarization during electron transfer to oxygen, slowing respiration. Here we show that the volatile anaesthetics isoflurane and sevoflurane specifically disrupt complex I-linked respiration in the thoraces of Drosophila melanogaster, with less effect on maximal respiration. Suppression of complex I-linked respiration was greatest with isoflurane. Using high-resolution tissue fluorespirometry, we show that these anaesthetics simultaneously increase mitochondrial membrane potential, implying reversal of the ATP synthase. Inhibition of ATP synthase with oligomycin prevented respiration and increased membrane potential back to the maximal (LEAK state) potential. Magnesium-green fluorescence predicted a collapse in ATP availability following a single anaesthetic dose, consistent with ATP hydrolysis through reversal of the ATP synthase. Raised membrane potential corresponded to a rise in ROS flux, especially with isoflurane. Anaesthetic doses causing respiratory suppression were in the same range as those that induce anaesthesia, although we could not establish tissue concentrations. Our findings show that anaesthetics suppress complex I-linked respiration with concerted downstream effects. But we cannot explain why only mutations in complex I, and not elsewhere in the electron-transfer system, confer hypersensitivity to anaesthetics.

300. SURFACE MICRODIALYSIS MEASURES LOCAL TISSUE METABOLISM AFTER IVOR LEWIS ESOPHAGECTOMY; AN ATTEMPT TO PREDICT ANASTOMOTIC DEFECT

Abstract Introduction Anastomotic defect after esophagectomy can lead to severe complications with need for surgical or endoscopic intervention. Early detection enables early treatment and can limit the consequences of the anastomotic defect. As of today, there are limited methods to predict anastomotic defect. In this study we have used microdialysis to measure local metabolism at the intrathoracic anastomosis. Feasibility and possible diagnostic use were investigated. Methods Sixty patients planned for Ivor Lewis esophagectomy were enrolled. After construction of the anastomosis, surface microdialysis probes were attached to the outer surface of the esophageal remnant and the gastric conduit in close vicinity of the anastomosis and left in place for seven postoperative days. Continuous sampling of local tissue concentrations of metabolic substances (glucose, lactate, pyruvate) was performed postoperatively. Outcome, defined as anastomotic defect or not according to ECCG (Esophagectomy Complications Consensus Group) definitions, was recorded at discharge or at first postoperative follow up. Difference in concentrations of metabolic substances were analysed retrospectively between the two groups by means of artificial neural network technique. Results Surface micodialysis probes can be attached and removed from the gastric tube reconstruction without any adverse events. Deviating metabolite concentrations on POD 1 were associated with later development of anastomotic defect. In subjects who developed anastomotic defects, no difference in metabolic concentrations between the esophageal and the gastric probe was recorded. The technical failure rate of the microdialysis probes/procedure was high. Discussion Surface microdialysis can be used in a clinical setting after Ivor Lewis esophagectomy. Deviation in local tissue metabolism on POD 1 seems to be associated with development of anastomotic defects. Further development of microdialysis probes and procedure is required to reduce technical failure.

O48 CHRONIC EXPOSURE TO POLLUTED URBAN AIR ALTERS MOUSE SYSTEMIC AND TISSUE-SPECIFIC COMPONENTS OF THE RENIN-ANGIOTENSIN SYSTEM (RAS)

Background and Objective: Chronic exposure to air pollution induces pulmonary, cardiovascular, and renal diseases. In the current study, we investigated the hypothesis that postulates that a dysregulation of the RAS may contribute to these pathologies. Methods: Male Balb/C mice were exposed to urban air from Buenos Aires City, in whole-body exposure chambers for 14 weeks. Control animals were exposed to filtered air. The levels of main RAS components including angiotensin-converting enzyme (ACE) and ACE2; AT1, AT2, and Mas receptors (R) were determined in mouse lungs, kidneys, and heart, through western blotting (WB) and RT-qPCR, respectively. The tissue content of cytokine mARN was determined by RT-qPCR. The tissue content of nitrotyrosine and 4-hydroxynonenal (4-HNE) levels, were determined by WB. Circulating angiotensin (Ang) II levels were determined by radioimmunoassay. Systolic blood pressure was measured by the tail-cuff method. Results: Exposure to air pollution resulted in a) Increased levels of ACE and AT1R mRNA in the lungs and augmented the abundance markers of inflammation (TNF-α, IL-6, and IL-1β) and oxidative stress (nitrotyrosine and 4-HNE) in this tissue, b) increased levels of MasR mRNA (all analyzed tissues) and MasR protein levels (lungs and heart), c) upregulated mRNA and protein abundance of cardiac and renal AT2Rs, and d) Increased levels of circulating Ang II and e) augmented systolic blood pressure. Conclusions: Our findings indicate that chronic exposure to air pollution alters the expression of both tissue and systemic components of the RAS. Since both AT2R and MasRs have been shown to participate in tissue-repair mechanisms, the upregulation of these receptors detected in mouse lungs, heart, and kidney after chronic exposure to polluted urban air could represent a mechanism of tissue protection against damage induced by air pollution.

Effects of glyphosate on glyphosate‐resistant maize growth and metabolic parameters in the greenhouse and field

AbstractThe potential adverse effects of glyphosate on glyphosate‐resistant (GR) crops are still a matter of controversy. The effects of glyphosate at recommended application rates (either a single application of 580 g ae ha−1 of glyphosate at stage V5 or a sequential application of 580 + 980 g ae ha−1 at stage V3 and V7, respectively) on growth, mineral content, and metabolic parameters of GR maize (Zea mays) were determined in greenhouse and field studies, each replicated in different years. No effects on any growth parameter (including grain yield), mineral content (leaf and grain), grain starch, crude protein, or total lipids were found. The only significant negative effect was a slight reduction in tyrosine content of leaf tissue with the sequential treatment, however, there was no increase in shikimic or quinic acids in leaf tissue with any treatment. In a separate greenhouse experiment, there was no sign of oxidative stress, as determined by levels of chlorophylls, carotenoids, and malondialdehyde (MDA) content as well as superoxide dismutase and guaiacol peroxidase activities 4 and 8 days after treatment with 1080 g ha−1 glyphosate. In fact, there was a reduction of MDA in roots of glyphosate‐treated plants 4 DAT, indicating reduced oxidative stress. No aminomethylphosphonic acid, the primary degradation product of glyphosate, was found in either leaves or grain of treated plants, and no glyphosate was found in grain of treated plants from the field studies. All the results are consistent with there being no adverse effects of glyphosate on GR maize at recommended application rates.

Fitoremediasi Air Tercemar Nikel (Ni) dan Merkuri (Hg) Menggunakan Tanaman Azolla filiculoides Lam.

Water pollution from settlements, agriculture, and industry is a significant issue, as it introduces pollutants like heavy metals into water bodies, harming both humans and aquatic ecosystems. Phytoremediation is a cost-effective, eco-friendly technology for reducing heavy metals in water bodies. This study aimed to assess Azolla filiculoides plants' ability to absorb heavy metals nickel and mercury. The plants were grown in a hydroponic solution contaminated with 0.25 ppm of nickel and 0.5 ppm of mercury. The growth of the plants was measured based on their wet and dry weight, and the nickel and mercury content in the plant tissue was analyzed using Atomic Absorption Spectrophotometry (AAS). The study found that the growth of A. filiculoides plants was unaffected by the concentration of either nickel or mercury. The amount of nickel absorbed by the plants was 0 µg/g plant dry weight, while for mercury, it was 1654.82 µg/g. Based on the results, A. filiculoides plant is more promising for use as a phytoremediation agent for water bodies contaminated with mercury heavy metals rather than nickel heavy metals.

The Abrolhos Nominally Herbivorous Coral Reef Fish Acanthurus chirurgus, Kyphosus sp., Scarus trispinosus, and Sparisoma axillare Have Similarities in Feeding But Species-Specific Microbiomes

Coral reefs rely heavily on reef fish for their health, yet overfishing has resulted in their decline, leading to an increase in fast-growing algae and changes in reef ecosystems, a phenomenon described as the phase-shift. A clearer understanding of the intricate interplay between herbivorous, their food, and their gut microbiomes could enhance reef health. This study examines the gut microbiome and isotopic markers (δ13C and δ15N) of four key nominally herbivorous reef fish species (Acanthurus chirurgus, Kyphosus sp., Scarus trispinosus, and Sparisoma axillare) in the Southwestern Atlantic’s Abrolhos Reef systems. Approximately 16.8 million 16S rRNA sequences were produced for the four fish species, with an average of 317,047 ± 57,007 per species. Bacteria such as Proteobacteria, Firmicutes, and Cyanobacteria were prevalent in their microbiomes. These fish show unique microbiomes that result from co-diversification, diet, and restricted movement. Coral-associated bacteria (Endozoicomonas, Rhizobia, and Ruegeria) were found in abundance in the gut contents of the parrotfish species Sc. trispinosus and Sp. axillare. These parrotfishes could aid coral health by disseminating such beneficial bacteria across the reef. Meanwhile, Kyphosus sp. predominantly had Pirellulaceae and Rhodobacteraceae. Four fish species had a diet composed of turf components (filamentous Cyanobacteria) and brown algae (Dictyopteris). They also had similar isotopic niches, suggesting they shared food sources. A significant difference was observed between the isotopic signature of fish muscular gut tissue and gut contents, pointing to the role that host genetics and gut microbes play in differentiating fish tissues.

The parasite prevalence in Clarias gariepinus from artificial and natural habitats in Oguta imo state Nigeria

This study revealed the presence of parasites in the two habitats under study. The endoparasites recovered were found to belong to Cammallanida, Pseudophyllida, and Plagiorchiida taxonomic group. Both habitats were noted to be sparingly infected; however, the natural habitat was more infected than the cultured habitat. The physicochemical parameters assayed in this study of the water and sediment samples from all the locations indicate that the water samples fall within the stipulated range of acceptability by the World Health Organization (WHO). The heavy metal concentrations in fish tissues were also within WHO set limits for the survival of aquatic organisms. However, prolonged consumption of the fish species will have adverse effects since heavy metals can bioaccumulate overtime. By implication, from the current result it may be confirmed that catfish obtained from fish pond is healthier than the uninhabited fish type in relationships of nutrient substances for human feeding. This could be due to the fact different habitat of different species the body pattern varies nutritionally. Findings from this work showed that constant monitoring of water parameters provide insight to the health of fish and aquatic ecosystems as whole. Finally, it can be inferred from the results of this study that for consumers purchasing the products in large quantities on a regularly basis, a public health hazard will definitely exist especially from natural catfish where pollution is more pronounced as a result of human activities. On the other side, no hazard might exist through the consumption of average amount of such fishes since it is within WHO permissible limits.