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Heliyon Nov 2023High fructose diet has been linked with impaired body metabolism and cardiovascular diseases. Sodium butyrate (NaB) was documented to improve glucoregulation and...
BACKGROUND
High fructose diet has been linked with impaired body metabolism and cardiovascular diseases. Sodium butyrate (NaB) was documented to improve glucoregulation and cardiometabolic problems associated with high fructose diet (HFrD) but the mechanisms behind it are unclear. As a result, the purpose of this study was to look into the effects of NaB on VEGF and cardiac lactate in HFrD-induced dysmetabolism.
METHODS
Twenty male Wistar rats of weight 130-140 g were assigned randomly after a week of acclimation into four groups: Control diet (CTR), High fructose drink (HFrD); 10 % (w/v), NaB (200 mg/kg bw), and HFrD + NaB (200 mg/kg bw). The animals were induced to be unconscious with 50 mg/kg of pentobarbital sodium intraperitoneally, blood samples were taken via cardiac puncture and cardiac tissue homogenates were obtained for Fasting Blood Sugar (FBS) and plasma insulin, cardiac glycogen, plasma and cardiac glycogen synthase, plasma and cardiac nitric oxide as well as vascular endothelial growth factor (VEGF).
RESULT
HFrD resulted in statistical elevation body and cardiac weight, plasma glucose, plasma insulin, cardiac lactate, glycogen and decreased nitric oxide level (NO) when compared with the control group. Administration of NaB reduced cardiac weight, blood glucose, plasma insulin, cardiac lactate while nitric oxide and glycogen increased (P < 0.05). NaB increased plasma glycogen synthase in normal rats, plasma and cardiac circulating VEGF in HFrD administered rats (P < 0.05) while no change was produced in plasma and cardiac glycogen synthase level of HFrD treated rats.
CONCLUSION
Sodium butyrate improves glucoregulation by reducing cardiac lactate and increasing circulating VEGF in HFrD-treated rats.
PubMed: 38034766
DOI: 10.1016/j.heliyon.2023.e22008 -
PeerJ 2023While cockroaches are commonly exhibited in zoos and museums, studied in research laboratories, and even kept as pets, scientifically based guidelines for their...
While cockroaches are commonly exhibited in zoos and museums, studied in research laboratories, and even kept as pets, scientifically based guidelines for their euthanasia are lacking. This study assessed euthanasia techniques in four species of cockroaches (Dubia (), red runner (), Madagascar hissing (), and giant cave ()). In an initial pilot study, two hundred fifty adult Dubia cockroaches were exposed in groups of ten to a cotton ball soaked with 2 mL of isoflurane in a 1 L air-tight chamber. Thirty minutes beyond loss of any individual movement, groups were exposed to one of the following secondary treatments: freezing at -18 °C or -80 °C from 0.25 to 24 hours; immersion in 10% neutral buffered formalin, 70% isopropyl alcohol, or reverse osmosis water for 0.25 or 0.5 hours; or intracoelomic injection of potassium chloride (456 mEq/kg) or pentobarbital-based euthanasia solution (3.9 g/kg). A control group remained in the air-tight isoflurane chamber for 24 hours. Following all treatments, cockroaches were monitored for an additional 24 hours for spontaneous movement. Irreversible loss of movement was considered synonymous with irreversible loss of consciousness (death). Across all species, isoflurane anesthesia followed by either 70% isopropyl alcohol immersion for 0.25 or 0.5 hours or isoflurane exposure for 24 hours resulted in euthanasia in 100% of cockroaches. This study is the first evaluation of American Veterinary Medical Association-recommended euthanasia protocols in cockroaches.
Topics: Animals; Cockroaches; Pilot Projects; 2-Propanol; Isoflurane; Caves
PubMed: 37927784
DOI: 10.7717/peerj.16199 -
Animals : An Open Access Journal From... Oct 2023Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This...
Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This study aimed to evaluate pain associated with six methods of euthanasia in Wistar rats (injectable, inhalational, and physical), by applying the Rat Grimace Scale (RGS), comparing the scores, and determining the method with the highest score that might indicate pain for laboratory rodents. Sixty adult male and female Wistar rats were used and assigned to six treatments: pentobarbital, CO, decapitation, isoflurane, ketamine + xylazine, and ketamine + CO. Video recording to assess the RGS scores was performed in four events: basal: 24 h before the procedure; Ti: three minutes before the procedure; Ti: during the application of the euthanasia method; and Ti: immediately after the application until LORR. The main findings of this study showed that, during Ti, decapitation and ketamine + xylazine had the highest scores (0.6 ± 0.26 and 0.6 ± 0.16, respectively) ( < 0.0001), while at Ti, CO (0.9 ± 0.18) and isoflurane (1.2 ± 0.20) recorded the highest scores ( < 0.0001). According to the present results, decapitation and ketamine + xylazine elicited short-term acute pain, possibly due to tissue damage caused by both methods (injection and guillotine). In contrast, isoflurane's RGS scores recorded during Ti might be associated with nociception/pain due to the pungency of the drug or to the pharmacological muscle relaxant effect of isoflurane. Further research is needed to establish a comprehensive study of pain during euthanasia, where RGS could be used minding the limitations that anesthetics might have on facial expression.
PubMed: 37893885
DOI: 10.3390/ani13203161 -
Antioxidants (Basel, Switzerland) Oct 2023is highly valued in traditional medicine and has been used to alleviate the symptoms of numerous diseases owing to its excellent antioxidant activity. This study aimed...
is highly valued in traditional medicine and has been used to alleviate the symptoms of numerous diseases owing to its excellent antioxidant activity. This study aimed to evaluate the sleep promotion and related signaling pathways of . extract (DE) via behavioral analysis, molecular biological techniques, and electrophysiological measurements in invertebrate and vertebrate models. In , the group treated with 4% DE experienced decreased subjective nighttime movement and sleep bout and increased total sleeping time. Moreover, substantial changes in locomotor activity, including distance moved, velocity, and movement, were confirmed in the 4% DE-treated group. Compared to in which insomnia and oxidative stress were induced by exposure to 0.1% caffeine, the DE-treated group improved sleep-related parameters to the level of the normal group. In the model, exposure to 4% DE upregulated the expression of gamma-aminobutyric acid (GABA)-related receptors and serotonin receptor (5-HT1A), along with the expression of antioxidant-related factors, glutathione, and catalase. In the pentobarbital-induced sleep test using ICR mice, the duration of sleep was markedly increased by high concentration of DE. In addition, through the electroencephalography analysis of SD-rats, a significant increase in non-rapid-eye-movement sleep and delta waves was confirmed with high concentrations of DE administration. The increase in sleep time and improvement in sleep quality were confirmed to be related to the expression of altered GABA receptors and the enhancement of the contents of the neurotransmitters GABA and serotonin (5-HT) because of high DE administration. High-dose administration of DE also increased the expression of antioxidant-related factors in the brain and significantly decreased malondialdehyde content. Taken together, DE induced improvements in sleep quantity and quality by regulating neurotransmitter content and related receptor expression, along with high antioxidant activity, and may have a therapeutic effect on sleep disorders.
PubMed: 37891970
DOI: 10.3390/antiox12101890 -
Animals : An Open Access Journal From... May 2023The effects of HS on the welfare of poultry have been reported to have a transgenerational effect on phenotype plasticity. The goal of our experiment was to determine...
The effects of HS on the welfare of poultry have been reported to have a transgenerational effect on phenotype plasticity. The goal of our experiment was to determine whether parental exposure to HS would impair the performance, HPA axis response, or behavior of their offspring. We treated adult drakes and hens (n = 80 ducks/treatment) at peak lay with HS or the control temperature for 3 weeks and incubated eggs collected from the last 3 days of the experiment. We utilized 76 ducklings/parental treatment group: control (CON-F) and HS (HS-F). Weekly data for body weights, body condition scores (BCSs), and novel object test (NOT) were collected. At 3 weeks of age, the ducks (n = 6/treatment) were subjected to adrenocorticotropic hormone (ACTH/cosyntropin, 0.0625 mg/kg) challenge or vehicle as the control. Blood samples were collected at 0, 1, 2, 3, and 4 h relative to treatment for serum glucocorticoid and heterophil-to-lymphocyte ratio (HLR) analyses. All injected birds were euthanized with pentobarbital on the second day relative to ACTH administration, and the spleen and bursa were removed and weighed immediately. Duck level analyses were completed using one- or two-way ANOVA as appropriate. BCSs were analyzed using a chi-squared test. The HS-F ducks had a lower hatch weight ( < 0.05) compared with the CON-F ducks but no significant difference in growth rates during the 5-week period. NOT (n = 4) analyses showed that the HS-F ducks had a greater fear response ( < 0.001) compared with the CON-F ducks. Similarly, an ACTH stimulation test showed that the HS-F ducks had significantly ( < 0.05) heightened corticosterone and HLR responses compared with the CON-F ducks. The HS-F ducks showed altered baseline and ACTH-stimulated levels of cortisol compared with the controls. Our data suggest that parental exposure to HS impacts the HPA response and fearfulness of the F generation in Pekin ducks.
PubMed: 37889638
DOI: 10.3390/ani13111748 -
Current Research in Toxicology 2023This study evaluated nickel and aluminium-induced neurotoxicity, as a binary metal mixture. Twenty-eight male Sprague Dawley albino rats were weight-matched and divided...
Nickel and aluminium mixture elicit memory impairment by activation of oxidative stress, COX-2, and diminution of AChE, BDNF and NGF levels in cerebral cortex and hippocampus of male albino rats.
This study evaluated nickel and aluminium-induced neurotoxicity, as a binary metal mixture. Twenty-eight male Sprague Dawley albino rats were weight-matched and divided into four groups. Group 1 (control) received deionized water. Group 2 and 3 received Aluminium (1 mg/kg) and Nickel (0.2 mg/kg) respectively, while Group 4 received Ni and Al mixture HMM three times a week orally for 90 days. Barnes maze tests was performed. Rats were sacrificed under pentobarbital anaesthesia, cerebral cortex and hippocampus were separated, and metal levels were measured using Atomic Absorption Spectroscopy (AAS). Malondialdehyde (MDA), catalase (CAT), glutathione content (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), Brain Derived Neurotrophic Factor (BDNF), Nerve growth factor NGF, -oxygenase COX-2 and Acetylcholinesterase (AChE) were assayed using ELISA kits. Ni/Al binary mixture exposed rats showed a shorter latency period (though not significant) of 3.21 ± 1.40 s in comparison to 3.77 ± 1.11 (Ni only) and 3.99 ± 1.16(Al only). Ni/Al mixture gp had the lowest levels of Mg in both the hippocampus and frontal cortex when compared with the individual metals. In the hippocampus Al only exposed rats significantly showed p < 0.05 higher iron and Ca levels in comparison to Ni/Al mixture. Al alone significantly showed p < 0.05 lower levels of Fe but higher Ca than the Ni/Al mixture group. Exposure to Al only showed lower levels of BDNF in comparison to Ni/Al combination, whereas Ni/Al mixture gp had lower levels of NGF in comparison to the individual metals in the hippocampus. In the frontal cortex Ni only, group showed significantly lower BDNF in comparison to Ni/Al mixture whereas the mixture showed significantly lower NGF when compared with Al only group. There were higher levels of COX-2 in the Ni/Al mixture than individual metal treated rats in both hippocampus and frontal cortex. AChE levels in the Ni/Al mixture group was higher than Ni or Al only gps in the hippocampus whereas in the frontal cortex, Ni/Al exposed rats showed significantly lower AChE levels in comparison to Al only group. Ni, Al and Ni/Al mixture exhibited memory impairment by activation of oxidative stress, COX-2, and diminution of AChE, BDNF and NGF levels in cerebral cortex and hippocampus. The BDNF-COX-2 AChE signalling pathway may be involved in the neurotoxicity of Ni and Al.
PubMed: 37841055
DOI: 10.1016/j.crtox.2023.100129 -
Frontiers in Physiology 2023Respiratory parameters in experimental animals are often characterised under general anaesthesia. However, anaesthesia regimes may alter the functional and mechanical...
Respiratory parameters in experimental animals are often characterised under general anaesthesia. However, anaesthesia regimes may alter the functional and mechanical properties of the respiratory system. While most anaesthesia regimes have been shown to affect the respiratory system, the effects of general anaesthesia protocols commonly used in animal models on lung function have not been systematically compared. The present study comprised 40 male Sprague-Dawley rats divided into five groups ( = 8 in each) according to anaesthesia regime applied: intravenous (iv) Na-pentobarbital, intraperitoneal (ip) ketamine-xylazine, iv propofol-fentanyl, inhaled sevoflurane, and ip urethane. All drugs were administered at commonly used doses. End-expiratory lung volume (EELV), airway resistance (Raw) and tissue mechanics were measured in addition to arterial blood gas parameters during mechanical ventilation while maintaining positive end-expiratory pressure (PEEP) values of 0, 3, and 6 cm HO. Respiratory mechanics were also measured during iv methacholine (MCh) challenges to assess bronchial responsiveness. While PEEP influenced baseline respiratory mechanics, EELV and blood gas parameters ( < 0.001), no between-group differences were observed ( > 0.10). Conversely, significantly lower doses of MCh were required to achieve the same elevation in Raw under ketamine-xylazine anaesthesia compared to the other groups. In the most frequent rodent model of respiratory disorders, no differences in baseline respiratory mechanics or function were observed between commonly used anaesthesia regimes. Bronchial hyperresponsiveness in response to ketamine-xylazine anaesthesia should be considered when designing experiments using this regime. The findings of the present study indicate commonly used anaesthetic regimes allow fair comparison of respiratory mechanics in experimental animals undergoing any of the examined anaesthesia protocols.
PubMed: 37791348
DOI: 10.3389/fphys.2023.1249127 -
BioRxiv : the Preprint Server For... Sep 2023Cortical electroencephalograms (EEG) may help understanding of neuropsychiatric illness and new treatment mechanisms. The aperiodic component (1/ ) of EEG power spectra...
UNLABELLED
Cortical electroencephalograms (EEG) may help understanding of neuropsychiatric illness and new treatment mechanisms. The aperiodic component (1/ ) of EEG power spectra is often treated as noise, but recent studies suggest that changes to the aperiodic exponent of power spectra may reflect changes in excitation/inhibition (E/I) balance, a concept linked to antidepressant effects, epilepsy, autism, and other clinical conditions. One confound of previous studies is behavioral state, because factors associated with behavioral state other than E/I ratio may alter EEG parameters. Thus, to test the robustness of the aperiodic exponent as a predictor of E/I ratio, we analyzed active exploration in mice using video EEG following various pharmacological manipulations with the Fitting Oscillations & One Over F (FOOOF) algorithm. We found that GABA receptor (GABA R) positive allosteric modulators increased the aperiodic exponent, consistent with the hypothesis that an increased exponent signals enhanced cortical inhibition, but other drugs (ketamine and GABA R antagonists at sub-convulsive doses) did not follow the prediction. To tilt E/I ratio more selectively toward excitation, we suppressed the activity of parvalbumin (PV) interneurons with Designer Receptors Exclusively Activated by Designer Drugs (DREADDs). Contrary to our expectations and studies demonstrating increased cortical activity following PV suppression, circuit disinhibition with the DREADD increased the aperiodic exponent. We conclude that the aperiodic exponent of EEG power spectra does not yield a universally reliable marker of E/I ratio. Alternatively, the concept of E/I state may be sufficiently oversimplified that it cannot be mapped readily onto an EEG parameter.
SIGNIFICANCE STATEBMENT
Neuropsychiatric illness is widely prevalent and debilitating. Causes are not well understood, but some hypotheses point toward altered excitation/inhibition (E/I) balance. Here, we use cortical electroencephalograms (EEG) in mice, given applicability of cortical EEG across species, and evaluate the impact of validated drugs, including anxiolytics (pentobarbital and diazepam), along with novel rapid-acting antidepressants (ketamine and allopregnanolone). We focus on analyzing the aperiodic component of EEG power spectra, which may be associated with changes in E/I ratio. We show that aperiodic exponent of EEG power spectra is not a reliable marker of E/I ratio. Moreover, the concept of E/I ratio may be too broad and complex to be defined by an EEG parameter.
PubMed: 37790570
DOI: 10.1101/2023.09.21.558828 -
Animals : An Open Access Journal From... Sep 2023Refinement is one of the principles aiming to promote welfare in research animals. The techniques used during an experimental protocol, including euthanasia selection,...
Refinement is one of the principles aiming to promote welfare in research animals. The techniques used during an experimental protocol, including euthanasia selection, must prevent and minimize suffering. Although the current euthanasia methods applied to laboratory rodents are accepted, the controversial findings regarding the potential stress/distress they can cause is a field of research. The objective was to assess the thermal response of Wistar rats during various euthanasia methods using infrared thermography (IRT) to determine the method that prevents or diminishes the stress response and prolonged suffering. Pentobarbital (G), CO (G), decapitation (G), isoflurane (G), ketamine + xylazine (G), and ketamine + CO (G) were evaluated at five evaluation times with IRT to identify changes in the surface temperature of four anatomical regions: ocular (T°), auricular (T°), interscapular (T°), and caudal (T°). Significant differences ( < 0.05) were found in G and G, registering temperature increases from the administration of the drug to the cessation of respiratory rate and heart rate. Particularly, isoflurane showed a marked thermal response in T°, T°, T°, and T°, suggesting that, in general, inhalant euthanasia methods induce stress in rats and that isoflurane might potentially cause distress, an effect that must be considered when deciding humane euthanasia methods in laboratory rodents.
PubMed: 37760220
DOI: 10.3390/ani13182820 -
Animals : An Open Access Journal From... Aug 2023Two young (11-week-old) pigs underwent sole propofol anaesthesia as part of an experimental study. The depth of anaesthesia was evaluated both clinically and using the...
Two young (11-week-old) pigs underwent sole propofol anaesthesia as part of an experimental study. The depth of anaesthesia was evaluated both clinically and using the electroencephalography(EEG)-based monitor Sedline; in particular, the patient state index, suppression ratio, raw EEG traces, and its spectrogram were assessed. Physiological parameters and electrocardiographic activity were continuously monitored. In one pig (Case 1), during the administration of high doses of propofol, the Sedline-generated variables suddenly indicated an increased EEG activity while this was not confirmed by observation of either the raw EEG or its spectrogram. In the second pig (Case 2), a similar event was recorded during euthanasia with systemic pentobarbital. Both events happened while the EEG activity was isoelectric except for signal interferences and synchronous in rhythm and shape with the electrocardiographic activity. The suggestion of increased brain activity based on the interpretation of the Sedline variables was suspected wrong; most probably due to electrocardiographic interferences. In pigs, the patient state index and suppression ratio, as calculated by the Sedline monitor, could be influenced by the electrocardiographic activity contaminating the EEG trace, especially during otherwise isoelectric periods (strong EEG depression). Visual interpretation of the raw EEG and of the spectrogram remains necessary to identify such artefacts.
PubMed: 37684963
DOI: 10.3390/ani13172699