Simultaneous determination of multiple components in rat plasma by UPLC-MS/MS for pharmacokinetic studies after oral administration of Pogostemon cablin extract.

Introduction: Pogostemon cablin (PC) is used in traditional Chinese medicine and food, as it exerts pharmacological effects, such as immune-modulatory, antibacterial, antioxidant, antitumor, and antiviral. Currently, the pharmacokinetics (PK) studies of PC mainly focus on individual components. However, research on these individual components cannot reflect the actual PK characteristics of PC after administration. Therefore, the simultaneous determination of multiple components in rat plasma using UPLC-MS/MS was used for the pharmacokinetic study after oral administration of PC extract in this study, providing reference value for the clinical application of PC. Methods: In the present study, a reliable and sensitive ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of 15 prototype components (vanillic acid, vitexin, verbascoside, isoacteoside, hyperoside, cosmosiin, apigenin, ß-rhamnocitrin, acacetin, ombuin, pogostone, pachypodol, vicenin-2, retusin, and diosmetin-7-O-ß-D-glucopyranoside) in rat plasma after oral administration of the PC extract. Plasma samples were prepared via protein precipitation using acetonitrile, and icariin was used as the internal standard (IS). Results: The intra-day and inter-day accuracies ranged from -12.0 to 14.3%, and the precision of the analytes was less than 11.3%. The extraction recovery rate of the analytes ranged from 70.6-104.5%, and the matrix effects ranged from 67.4-104.8%. Stability studies proved that the analytes were stable under the tested conditions, with a relative standard deviation lower than 14.1%. Conclusion: The developed method can be applied to evaluate the PK of 15 prototype components in PC extracts of rats after oral administration using UPLC-MS/MS, providing valuable information for the development and clinical safe, effective, and rational use of PC.

Low protein digestibility-corrected amino acid score and net nitrogen-to-protein conversion factor value of edible insects.

The amount of chitin, a nitrogen-containing dietary fiber, in edible insects can mislead the exact nitrogen-to-protein conversion factor (NPF) and true protein content. We determined the amino acid score (AAS), protein digestibility-corrected AAS (PDCAAS), chitin content, and net NPF of five edible insects. Additionally, the effect of the amino acid composition of migratory locust on rat growth were investigated. The AAS of the insects were ranged from 63 to 94. The chitin contents were ranged from 1.6 g/100 g to 10.7 g/100 g. The PDCAAS, calculated by AAS and gut-intestinal digestibility, ranged from 44 to 81, which was lower than casein (97). The net NPF ranged from 4.93 to 5.76, which were lower than the conventional value. Dietary migratory locust, whose PDCAAS was the lowest, decreased growth and altered lipid metabolism. Therefore, a lower PDCAAS and overestimation of net NPF of insects can affect the true protein calculations and growth.

Gray matter atrophy in a 6-OHDA-induced model of Parkinson's disease.

INTRODUCTION: Magnetic resonance imaging (MRI) based brain morphometric changes in unilateral 6-hydroxydopamine (6-OHDA) induced Parkinson's disease (PD) model can be elucidated using volume-based morphometry (VBM), study of alterations in gray matter volume and Machine Learning (ML) based analyses. METHODS: We investigated gray matter atrophy in 6-OHDA induced PD model as compared to sham control using statistical and ML based analysis. VBM and atlas-based volumetric analysis was carried out at regional level. Support vector machine (SVM)-based algorithms wherein (a) features (volume) extracted from each of the 150 brain regions (b) statistically significant features (only) and (c) volumes of each cluster identified after application of VBM (VBM_Vol) were used for training the decision model. The lesion of the 6-OHDA model was validated by estimating the net contralateral rotational behaviour by the injection of apomorphine drug and motor impairment was assessed by rotarod and open field test. RESULTS AND DISCUSSION: In PD, gray matter volume (GMV) atrophy was noted in bilateral cortical and subcortical brain regions, especially in the internal capsule, substantia nigra, midbrain, primary motor cortex and basal ganglia-thalamocortical circuits in comparison with sham control. Behavioural results revealed an impairment in motor performance. SVM analysis showed 100% classification accuracy, sensitivity and specificity at both 3 and 7 weeks using VBM_Vol. CONCLUSION: Unilateral 6-OHDA induced GMV changes in both hemispheres at 7th week may be associated with progression of the disease in the PD model. SVM based approaches provide an increased classification accuracy to elucidate GMV atrophy.

Differential effects of moderate chronic ethanol consumption on neurobehavior, white matter glial protein expression, and mTOR pathway signaling with adolescent brain maturation.

Background: Adolescent brains are highly vulnerable to heavy alcohol exposure. Increased understanding of how alcohol adversely impacts brain maturation may improve treatment outcomes.Objectives: This study characterizes short-term versus long-term effects of ethanol feeding on behavior, frontal lobe glial proteins, and mTOR signaling.Methods: Adolescent rats (8/group) were fed liquid diets containing 26% or 0% ethanol for 2 or 9 weeks, then subjected to novel object recognition (NOR) and open field (OF) tests. Frontal lobes were used for molecular assays.Results: Significant ethanol effects on OF performance occurred in the 2-week model (p < .0001). Further shifts in OF and NOR performance were unrelated to ethanol exposure in the 9-week models (p < .05 to p < .0001). Ethanol inhibited MAG1 (p < .01) and MBP (p < .0001) after 2 but not 9 weeks. However, both control and ethanol 9-week models had significantly reduced MAG1 (p < .001-0.0001), MBP (p < .0001), PDGFRA (p < .05-0.01), and PLP (p < .001-0.0001) relative to the 2-week models. GFAP was the only glial protein significantly inhibited by ethanol in both 2- (p < .01) and 9-week (p < .05) models. Concerning the mTOR pathway, ethanol reduced IRS-1 (p < .05) and globally inhibited mTOR (p < .01 or p < .001) in the 9- but not the 2-week model.Conclusions: Short-term versus long-term ethanol exposures differentially alter neurobehavioral function, glial protein expression, and signaling through IRS-1 and mTOR, which have known roles in myelination during adolescence. These findings suggest that strategies to prevent chronic alcohol-related brain pathology should consider the increased maturation-related vulnerability of adolescent brains.

Beta vulgaris L. var cicla decreases liver injury induced by antiarrhytmic agent, Amiodarone.

Amiodarone (AMD) is an effective antiarrhythmic drug, but its long-term usage strongly forms liver toxicity due to its accumulation tendency. The chard is a unique plant which has a blood sugar-lowering effect and powerful antioxidant activity. The aim of the current study was to investigate the possible protective effects of chard on AMD-induced liver injury. Male Sprague-Dawley rats were divided into four groups. Control group, aqueous chard extract given group (500 mg/kg) day for one week, AMD given group (100 mg/kg) /day for one week, AMD+Chard given group (at the same doses and times). They were sacrificed on the 8th day. The blood and liver samples were taken. The serum and liver biochemical parameters were found to be changed in AMD treated group. Chard administration reversed these parameters in serum and liver. In histological experiments, necrotic areas, mononuclear cell infiltration, the endothelial rupture in central vein, sinusoidal dilatation, hyperemia, dark eosinophilic cells and picnotic nucleus were observed in liver tissues of AMD treated group. Chard treatment reduced liver tissue damage. Considering results, we can suggest that chard prevented AMD induced liver injury biochemically and histologically.

Active immunization with recombinant GnRH6-CRM197 inhibits reproductive function of male rats.

Gonadotropin-releasing hormone (GnRH) vaccines have been successfully used for the inhibition of gonadal development and function, but current GnRH-based vaccines often present variability in the response. Cross-reactive material 197 (CRM197) has been used as carrier molecules to enhance an immune response to associated antigens. So, the synthetic mammalian tandem-repeated GnRH hexamer (GnRH6) gene was integrated into the expression plasmid pET-21a. Recombinant GnRH6-CRM197 protein was subsequently overexpressed in Escherichia coli strain BL21 and purified through Nickel column affinity chromatography and the antigenicity and biological effects of GnRH6-CRM197 were evaluated in rats. Sixteen 4-month-old adult male rats were randomly divided into two groups: the GnRH6-CRM197 group (n = 8) and the control group (n = 8). The GnRH6-CRM197 group rats were subcutaneously immunized with 100 µg of GnRH6-CRM197, administered thrice at 2-week intervals with GnRH6-CRM197.The control group received only a white oil adjuvant. Following the initial immunization, the weights of animals were recorded, and blood samples were collected from the orbital sinus at 4, 4.5, 5, 5.5, 6, 6.5, and 7 months. Serum antibody titers and testosterone concentrations were quantified using ELISA and CLIA, respectively. Additionally, testicular tissues were collected for morphological examination. The results revealed a significant increase in serum GnRH antibody titers (p < 0.05), but a significant decrease in serum testosterone concentrations (p < 0.05), and the weight, length, width, and girth of the testis, and the number of spermatogonia cells, spermatocytes, and sperm cells in the immunized rats. Furthermore, seminiferous tubules revealed significant atrophy and no sperm were observed in the immunized animals. Thus, GnRH6-CRM197 may be an effective antigen and a potential immunocastration vaccine.

Consumption of Soya Isoflavones Improved Polycystic Ovary Syndrome (PCOS)-Associated Metabolic Disorders in a Rat Model.

Polycystic ovary syndrome (PCOS) is associated with increased risks for certain metabolic disorders such as insulin resistance, non-alcoholic fatty liver disease (NAFLD), and suppressed ovarian follicular development. This study aimed to examine whether soya isoflavones (ISF) mitigate these PCOS-associated metabolic disorders in a rat model. Weanling Sprague-Dawley female rats were randomly divided into 6 groups and were treated with either 0 or 83 µg/day dihydrotestosterone (DHT) to induce PCOS and fed diets containing 0, 0.5, or 1g ISF/kg diet for 8 weeks. DHT treatment increased food intake, body weight gain (BWG, p<0.001), percentage of primordial follicles (60% vs 50.9%, p<0.05), and accumulation of lipid droplets in the livers. It also elevated serum total cholesterol (TC), free cholesterol (FC), triglycerides, non-esterified fatty acids (NEFA), and leptin, and hepatic TC and NEFA. Additionally, DHT treatment reduced the percentage of primary follicles (13.8% vs 30.2%, p<0.05), ovary weight, and length (p<0.001), as well as insulin sensitivity (p<0.01) compared to the Control. ISF intake at 1g/kg reduced BWG, serum TC, FC, NEFA, leptin, and hepatic triglycerides and DHT-induced insulin resistance (p<0.01). ISF intake at both levels decreased DHT-induced lipid droplet accumulation in the livers, and changes in the percentages of primordial and primary follicles. Dietary soya ISF alleviated DHT-induced BWG, insulin resistance, and hepatic lipid droplet accumulation, as well as suppressed ovarian follicular development. This suggests that consumption of soya foods or ISF supplements may be beneficial for the individuals with PCOS, mitigating the associated metabolic disorders such as diabetes and NAFLD.

Evaluation of the potential role of glutamatergic, cholinergic, and nitrergic systems in the dopamine release induced by the pesticide glyphosate in rat striatum.

Glyphosate (GLY) is a pesticide that severely alters nigrostriatal dopaminergic neurotransmission, inducing great increases in dopamine release from rat dorsal striatum. This GLY-induced striatal dopamine overflow occurs through mechanisms not yet fully understood, hence the interest in evaluating the role of other neurotransmitter systems in such effects. So, the main objective of this mechanistic study was to evaluate the possible mediation of the glutamatergic, cholinergic, and nitrergic systems in the GLY-induced in vivo dopamine release from rat dorsal striatum. The extracellular dopamine levels were measured by cerebral microdialysis and HPLC with electrochemical detection. Intrastriatal administration of GLY (5 mmol/L) significantly increased the dopamine release (1102%). Pretreatment with MK-801 (50 or 400 µmol/L), a non-competitive antagonist of NMDA receptors, significantly decreased the effect of GLY (by 70% and 74%, respectively), whereas AP-5 (400 µmol/L), a competitive antagonist of NMDA receptors, or CNQX (500 µmol/L), an AMPA/kainate receptor antagonist, had no significant effect. Administration of the nitric oxide synthase inhibitors, L-nitroarginine (L-NAME, 100 µmol/L) or 7-nitroindazole (7-NI, 100 µmol/L), also did not alter the effect of GLY on dopamine release. Finally, pretreatment of the animals with mecamylamine, an antagonist of nicotinic receptors, decreased the effect of GLY on dopamine release by 49%, whereas atropine, a muscarinic antagonist, had no significant effect. These results indicate that GLY-induced dopamine release largely depends on the activation of NMDA and nicotinic receptors in rat dorsal striatum. Future research is needed to determine the effects of this pesticide at environmentally relevant concentrations.

Rodent anogenital distance recommendations.

BACKGROUND: Measurement of rat anogenital distance (AGD) dates to at least 1912. Increased interest in endocrine disrupting chemicals and the use of AGD as a biomarker for fetal androgen effects have increased the number of studies with this endpoint in recent decades. A literature review revealed different landmarks, methods of measurement, and methods to adjust for body weight differences. AGD is often reported to hundredths of millimeters and as such, deserves precision in all these aspects. This paper presents recommendations for the measurement and analysis of rodent AGD. METHODS: Literature and regulatory guidance documents that mentioned or measured rodent AGD were reviewed. Four adjustment methods were evaluated using available online data from three rat studies each with two generations of offspring. RESULTS: Tabulation of studies reveals that species/stocks and time of data collection, but more importantly anatomical landmarks and methods of measurement have produced a variety of results which are difficult to compare. Not all studies have adjusted for test article effects on body weight (and thus size). The four adjustment methods were fairly comparable. CONCLUSION: Recommendations are as follows. A microscopic method should be used to measure AGD of late rodent fetuses and early postnatal pups. The caudal edge of the genital tubercle and the cranial edge of the anus are clear and identifiable landmarks. The simplest adjustment is to divide individual AGDs by the cube root of animals' body weight. These recommendations will help ensure data consistency and accuracy, and facilitate meaningful comparisons across laboratories and chemical classes.

Erratum: Role of environmental enrichment on social interaction, anxiety, locomotion, and memory in Wistar rats under chronic methylphenidate intake.

[This corrects the article DOI: 10.3389/fnbeh.2023.1251144.].

Ameliorative effects of Wikstroemia trichotoma 95% EtOH extract on a mouse model of DNCB-induced atopic dermatitis.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Wikstroemia has been extensively utilized in traditional Chinese medicine (TCM) for the management of conditions such as coughs, edema, arthritis, and bronchitis. Studies have indicated that the crude extracts of Wikstroemia exhibit anti-inflammatory, anti-allergy, anti-aging, skin psoriasis, anti-cancer, and antiviral properties. In addition, these extracts are known to contain bioactive substances, including flavonoids, coumarins, and lignans. However, few studies have investigated the anti-inflammatory or anti-allergic activities of Wikstroemia trichotoma (Thunb.) Makino against atopic dermatitis (AD). AIM OF THE STUDY: The study aimed to explore the potential of a 95% ethanol extract of W. trichotoma (WTE) on the dysfunction of skin barrier and immune system, which are primary symptoms of AD, in 2,4-dinitrochlorobenzene (DNCB)-induced SKH-1 hairless mice and phorbol 12-myristate 13-acetate (PMA)/ionomycin or immunoglobulin E (IgE) + 2,4-dinitrophenylated bovine serum albumin (DNP-BSA) stimulated rat basophilic leukemia cell line (RBL-2H3). Furthermore, we sought to identify the chemical contents of WTE using high-performance liquid chromatography equipped with a photodiode array detector (HPLC-PDA). MATERIALS AND METHODS: An in vitro study was conducted using RBL-2H3 cells stimulated with PMA/ionomycin or IgE + DNP-BSA to assess the inhibitory effects of WTE on mast cell degranulation and interleukin-4 (IL-4) mRNA expression levels. For the in vivo study, AD was induced in SKH-1 hairless mice by applying 1% DNCB to the dorsal skin daily for 7 days. Subsequently, 0.1% DNCB solution was applied on alternate days, and mice were orally administered WTE (at 30 or 100 mg/kg/day) dissolved in 0.5% carboxymethyl cellulose (CMC) daily for 2 weeks. Transepidermal water loss (TEWL), skin hydration, skin pH, and total serum IgE levels were measured. RESULTS: In DNCB-stimulated SKH-1 hairless mice, WTE administration significantly improved AD symptoms and ameliorated dorsal skin inflammation. Oral administration of WTE led to a significant decrease in skin thickness, infiltration of mast cells, and level of total serum IgE, thus restoring skin barrier function in the DNCB-induced skin lesions. In addition, WTE inhibited ß-hexosaminidase release and reduced IL-4 mRNA levels in RBL-2H3 cells. Chemical profile analysis of WTE confirmed the presence of three phenolic compounds, viz. chlorogenic acid, miconioside B, and matteucinol-7-O-ß-apiofuranosyl (1 â†’ 6)-ß-glucopyranoside. CONCLUSIONS: WTE ameliorates AD symptoms by modulating in the skin barrier and immune system dysfunction. This suggests that W. trichotoma extract may offer therapeutic benefits for managing AD.

Determination of tissue distribution of VX and its metabolites EMPA and EA-2192 in various rat tissues by LC-ESI-MS/MS after phosphotriesterase treatment.

Phosphotriesterases (PTE) are a new and promising approach for the treatment of organophosphate poisoning, since the current therapy of such intoxications shows some limitations. A previous rat in vivo study confirmed the therapeutic effect of PTE, which were specifically designed for VX breakdown, and demonstrated rapid degradation of VX in whole blood samples. The present study now focuses on the degradation of VX and its distribution in organ tissues of the animals used in the aforementioned study. In order to gain a broader overview, we have extended the investigations to the VX metabolites EA-2192 and EMPA by using methods developed for an LC-ESI-MS/MS system. Applying these methods, we were able to verify the effectiveness of the PTE treatment and gained an overview of VX tissue distribution in poisoned but untreated rats.

Understanding How Acute Alcohol Impacts Neural Encoding in the Rodent Brain.

Alcohol impacts neural circuitry throughout the brain and has wide-ranging effects on the biophysical properties of neurons in these circuits. Articulating how these wide-ranging effects might eventually result in altered computational properties has the potential to provide a tractable working model of how alcohol alters neural encoding. This chapter reviews what is currently known about how acute alcohol influences neural activity in cortical, hippocampal, and dopaminergic circuits as these have been the primary focus of understanding how alcohol alters neural computation. While other neural systems have been the focus of exhaustive work on this topic, these brain regions are the ones where in vivo neural recordings are available, thus optimally suited to make the link between changes in neural activity and behavior. Rodent models have been key in developing an understanding of how alcohol impacts the function of these circuits, and this chapter therefore focuses on work from mice and rats. While progress has been made, it is critical to understand the challenges and caveats associated with experimental procedures, especially when performed in vivo, which are designed to answer this question and if/how to translate these data to humans. The hypothesis is discussed that alcohol impairs the ability of neural circuits to acquire states of neural activity that are transiently elevated and characterized by increased complexity. It is hypothesized that these changes are distinct from the traditional view of alcohol being a depressant of neural activity in the forebrain.

The effects of MEPaL on oxidative stress and motor function in the rats affected by prenatal hypoxia.

BACKGROUND AND OBJECTIVES: Maternal hypoxia disrupts neural development and subsequently leads to cerebral palsy and epilepsy in newborns. Hypoxia plays a role in neurodegeneration by increasing oxidative stress. Pistacia atlantica is known as an important antioxidant, and its anti-inflammatory and antioxidant effects have been shown in various studies. This study aims to investigate the effects of methanolic extract of P. atlantica leaves (MEPaLs) on the oxidative parameters in the serum of rats affected by maternal hypoxia. MATERIAL AND METHODS: In this study, eight pregnant rats were used. The newborns were divided into four groups, including the control and the hypoxia groups, which are affected by maternal hypoxia, hypoxia + MEPaL 100 mg/kg, and hypoxia + MEPaL 150 mg/kg. MEPaL was injected (i.p) for 21 days into the neonatal rats after the lactation period. Hypoxia was induced by keeping pregnant rats in a hypoxic chamber with 7% oxygen and 93% nitrogen intensity for 3 h on the 20th day of pregnancy. Behavioral changes were measured using open-field and rotarod tests. Finally, biomarkers of oxidative stress, nitric oxide (NO), glutathione (GSH), GSSG, TAS, TOS, and oxidative stress index (OSI) were measured in the experimental groups. RESULTS: Behavioral results showed that the anxiety behavior in the hypoxia group increased, but the motor activity (moved distance and movement speed) decreased. Moreover, the amount of time spent maintaining balance on the rotarod rod was significantly decreased in the hypoxia group. The concentration of NO in the group of hypoxia + MEPaL 100 mg/kg showed a significant decrease, and MEPaL 100, and 150 mg/kg + hypoxia also increased the concentration of GSH and decreased GSSG. In addition, MEPaL100 and 150 mg/kg caused a significant increase in the ratio of GSH to GSSG and decreased OSI and total oxidant capacity. CONCLUSIONS: Oxidative stress increased in the rats affected by maternal hypoxia and may be the main mechanism for motor activity impairment and balance disturbance, whereas MELaL improved motor performance by decreasing oxidative stress.

Prazosin Potentiates Mast Cell-Stabilizing Property of Adrenaline.

BACKGROUND/AIMS: Adrenaline quickly inhibits the release of histamine from mast cells. Besides ß2-adrenergic receptors, several in vitro studies also indicate the involvement of α-adrenergic receptors in the process of exocytosis. Since exocytosis in mast cells can be detected electrophysiologically by the changes in the membrane capacitance (Cm), its continuous monitoring in the presence of drugs would determine their mast cell-stabilizing properties. METHODS: Employing the whole-cell patch-clamp technique in rat peritoneal mast cells, we examined the effects of adrenaline on the degranulation of mast cells and the increase in the Cm during exocytosis. We also examined the degranulation of mast cells in the presence or absence of α-adrenergic receptor agonists or antagonists. RESULTS: Adrenaline dose-dependently suppressed the GTP-γ-S-induced increase in the Cm and inhibited the degranulation from mast cells, which was almost completely erased in the presence of butoxamine, a ß2-adrenergic receptor antagonist. Among α-adrenergic receptor agonists or antagonists, high dose prazosin, a selective α1-adrenergic receptor antagonist, significantly reduced the ratio of degranulating mast cells and suppressed the increase in the Cm. Additionally, prazosin augmented the inhibitory effects of adrenaline on the degranulation of mast cells. CONCLUSION: This study provided electrophysiological evidence for the first time that adrenaline dose-dependently inhibited the process of exocytosis, confirming its usefulness as a potent mast cell-stabilizer. The pharmacological blockade of α1-adrenergic receptor by prazosin synergistically potentiated such mast cell-stabilizing property of adrenaline, which is primarily mediated by ß2-adrenergic receptors.

Fluoxetin suppresses tau phosphorylation and modulates the interaction between tau and tubulin in the hippocampus of CUMS rats.

Depression is considered a crucial psychiatric disease correlated with neuronal-dysfunctions induced by stress-stimuli. This study aimed to investigate effect of Fluoxetine (FL) on chronic unpredictable mild stress (CUMS) and explore the associated mechanisms. CUMS rat model was established by treating with lots of stresses. CUMS rats were administered FL, SB216763 (SB), Wortmannin (WT) alone or in combination. CUMS rats were administered 1 % sugar water to conduct sugar water consumption experiment. Acet-Tub, Tyr-Tub, tau46, p-tau-Ser199/202, p-tau-Ser396, p-tau-Ser231, expression was examined using immunohistochemical assay and western blotassay. Interaction between tau and tubulin was evaluated with immunoprecipitation assay. Double immunohistochemical assay was used to identify interaction between Nestin and Tau. The results indicated that FL treatment only increased sugar consumption of CUMS rats (P < 0.05), but also strengthened effects of SB and WT. FL significantly treatment decreased tau phosphorylation (p-tau) in hippocampal tissues of rats compared to those of rats in CUMS group (P < 0.05). FL treatment markedly decreased Acet-Tub and increased Tyr-Tub expression in hippocampal tissues of rats compared to those of rats in CUMS group (P < 0.05). The effects of FL treatment on p-tau down-regulation and tubulin modulation in hippocampal tissues were independent from PI3K and GSK-3 signaling pathways. FL treatment could also enhance proliferation and total tau of newborn neurons of CUMS rats. FL treatment strengthened interaction between tau and botulin in hippocampal tissues of CUMS rats. In conclusion, Fluoxetin suppressed phosphorylation of tau and modulated the interaction between tau and tubulin in hippocampus of adult CUMS rats.

Uncovering the neural control of laryngeal activity and subglottic pressure in anaesthetized rats: insights from mesencephalic regions.

To assess the possible interactions between the dorsolateral periaqueductal gray matter (dlPAG) and the different domains of the nucleus ambiguus (nA), we have examined the pattern of double-staining c-Fos/FoxP2 protein immunoreactivity (c-Fos-ir/FoxP2-ir) and tyrosine hydroxylase (TH) throughout the rostrocaudal extent of nA in spontaneously breathing anaesthetised male Sprague-Dawley rats during dlPAG electrical stimulation. Activation of the dlPAG elicited a selective increase in c-Fos-ir with an ipsilateral predominance in the somatas of the loose (p < 0.05) and compact formation (p < 0.01) within the nA and confirmed the expression of FoxP2 bilaterally in all the domains within the nA. A second group of experiments was made to examine the importance of the dlPAG in modulating the laryngeal response evoked after electrical or chemical (glutamate) dlPAG stimulations. Both electrical and chemical stimulations evoked a significant decrease in laryngeal resistance (subglottal pressure) (p < 0.001) accompanied with an increase in respiratory rate together with a pressor and tachycardic response. The results of our study contribute to new data on the role of the mesencephalic neuronal circuits in the control mechanisms of subglottic pressure and laryngeal activity.

Quantification of 11 metabolites in rat urine after exposure to organophosphates.

BACKGROUND: The aim of the study was to develop a technique for quantitative determination of rat urine metabolites by HPLC-MS/MS, which can be used to search for biomarkers of acute intoxication with organophosphates (OPs). RESULTS: The content of metabolites in the urine of rats exposed to a single dose of paraoxon (POX1x); interval, twice daily administration of paraoxon (POX2x); exposure to 2-(o-cresyl)-4H-1, 3, 2-benzodioxaphosphorin-2-oxide and paraoxon (CBPOX) was investigated. New data were obtained on the content in the urine of intact rats as well as rats in 3 models of OP poisoning: 3-methylhistidine, threonine, creatine, creatinine, lactic acid, acetylcarnitine, inosine, hypoxanthine, adenine, 3-hydroxymethyl-butyrate and 2-hydroxymethyl-butyrate. CONCLUSIONS: The proposed assay procedure is a simple and reliable tool for urine metabolomic studies. Within 1-3 days after OP exposure in all three models of acute intoxication, the concentration of metabolites in rat urine, with the exception of adenine, changes similarly and symmetrically, regardless of the method of poisoning modeling, in all three models of acute intoxication. Further studies are needed to determine the specificity and reliability of using urinary metabolite concentration changes as potential biomarkers of acute organophosphate intoxication.

ICH S1 prospective evaluation study and weight of evidence assessments: commentary from industry representatives.

Industry representatives on the ICH S1B(R1) Expert Working Group (EWG) worked closely with colleagues from the Drug Regulatory Authorities to develop an addendum to the ICH S1B guideline on carcinogenicity studies that allows for a weight-of-evidence (WoE) carcinogenicity assessment in some cases, rather than conducting a 2-year rat carcinogenicity study. A subgroup of the EWG composed of regulators have published in this issue a detailed analysis of the Prospective Evaluation Study (PES) conducted under the auspices of the ICH S1B(R1) EWG. Based on the experience gained through the Prospective Evaluation Study (PES) process, industry members of the EWG have prepared the following commentary to aid sponsors in assessing the standard WoE factors, considering how novel investigative approaches may be used to support a WoE assessment, and preparing appropriate documentation of the WoE assessment for presentation to regulatory authorities. The commentary also reviews some of the implementation challenges sponsors must consider in developing a carcinogenicity assessment strategy. Finally, case examples drawn from previously marketed products are provided as a supplement to this commentary to provide additional examples of how WoE criteria may be applied. The information and opinions expressed in this commentary are aimed at increasing the quality of WoE assessments to ensure the successful implementation of this approach.

Greater cane rat algorithm (GCRA): A nature-inspired metaheuristic for optimization problems.

This paper introduces a new metaheuristic technique known as the Greater Cane Rat Algorithm (GCRA) for addressing optimization problems. The optimization process of GCRA is inspired by the intelligent foraging behaviors of greater cane rats during and off mating season. Being highly nocturnal, they are intelligible enough to leave trails as they forage through reeds and grass. Such trails would subsequently lead to food and water sources and shelter. The exploration phase is achieved when they leave the different shelters scattered around their territory to forage and leave trails. It is presumed that the alpha male maintains knowledge about these routes, and as a result, other rats modify their location according to this information. Also, the males are aware of the breeding season and separate themselves from the group. The assumption is that once the group is separated during this season, the foraging activities are concentrated within areas of abundant food sources, which aids the exploitation. Hence, the smart foraging paths and behaviors during the mating season are mathematically represented to realize the design of the GCR algorithm and carry out the optimization tasks. The performance of GCRA is tested using twenty-two classical benchmark functions, ten CEC 2020 complex functions, and the CEC 2011 real-world continuous benchmark problems. To further test the performance of the proposed algorithm, six classic problems in the engineering domain were used. Furthermore, a thorough analysis of computational and convergence results is presented to shed light on the efficacy and stability levels of GCRA. The statistical significance of the results is compared with ten state-of-the-art algorithms using Friedman's and Wilcoxon's signed rank tests. These findings show that GCRA produced optimal or nearly optimal solutions and evaded the trap of local minima, distinguishing it from the rival optimization algorithms employed to tackle similar problems. The GCRA optimizer source code is publicly available at: https://www.mathworks.com/matlabcentral/fileexchange/165241-greater-cane-rat-algorithm-gcra.