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Pharmaceutics Mar 2024A particular attribute of the brain lies in the ability to learn, acquire information from the environment, and utilize the learned information. Previous research has...
A particular attribute of the brain lies in the ability to learn, acquire information from the environment, and utilize the learned information. Previous research has noted that various factors (e.g., age, stress, anxiety, pathological issues), including antipsychotic medications, affect the brain and memory. The current study aimed to reveal the effects of chronic metformin treatment on the cognitive performance of rats and on commonly measured markers for oxidative stress. Wistar male rats (n = 40) were randomly divided into four groups: CTR (n = 10)-control group, METF (n = 10)-animals receiving metformin 500 mg/kg, HAL (n = 10)-animals receiving haloperidol 2 mg/kg, and HALMETF (n = 10)-animals receiving haloperidol 2 mg/kg and metformin 500 mg/kg. The medication was administered daily by oral gavage for 40 days. Memory and learning were assessed using the Morris Water Maze (MWM) test. At the end of the MWM, the rodents were decapitated under anesthesia, and the brain and blood samples were assayed by liquid chromatography for markers of oxidative stress (malondialdehyde, MDA, reduced/oxidized glutathione ratio, GSH/GSSG). The quantification of brain-derived neurotrophic factor (BDNF) was performed using the conventional sandwich ELISA technique. In the HALMETF group, metformin attenuated the negative effects of haloperidol. Brain and plasma MDA levels increased in the HAL group. Brain and plasma GSH/GSSG ratios and BDNF levels did not reveal any differences between groups. In conclusion, metformin treatment limits the deleterious cognitive effects of haloperidol. The effect on oxidative stress markers may also point toward an antioxidant-like effect of metformin, but this needs further tests for confirmation.
PubMed: 38543297
DOI: 10.3390/pharmaceutics16030403 -
Journal of Korean Neurosurgical Society Mar 2024Dexpanthenol (DXP), which has known neuroprotective effects, has been shown to be beneficial in various experimental models and ischaemic diseases. The aim of this study...
OBJECTIVE
Dexpanthenol (DXP), which has known neuroprotective effects, has been shown to be beneficial in various experimental models and ischaemic diseases. The aim of this study was to investigate the possible neuroprotective effects of DXP in a traumatic brain injury (TBI) model.
METHODS
Thirty-six Wistar-Albino female rats, approximately 6 months old, weighing 220-285 g were used. All rats were subjected to closed head trauma by dropping a weight of 350 g on the parietal region from a height of 50 cm at an angle of 180 degrees in the prepared head trauma model setup. The rats were divided into four groups as control (group 1), trauma (group 2), trauma + DXP (group 3), and DXP (group 4). In group 3, DXP was administered intraperitoneally at a dose of 500 mg/kg for six times at 30 minutes, 6, 12, 24, 36, and 48 hours. In group 4, DXP was administered intraperitoneally simultaneously with group 3 without causing head trauma. Blood samples were taken from all rats 72 hours later for biochemical examination. After blood samples were taken, rats were decapitated under general anaesthesia. Cerebral tissue samples were taken from decapitated rats for immunohistochemical and histopathological examination.
RESULTS
Cytokine markers were found to be increased in posttraumatic brain tissue. Malondialdehyde and glutathione reductase levels were lower in group 3 compared to group 2. In addition, superoxide dismutase, glutathione peroxidase and catalase levels were significantly higher in group 3 compared to group 2. In histological evaluation, congestion in the piamater layer, cell infiltration, vascular congestion, hemorrhage and neuronal degeneration were significantly decreased in group 3 compared to group 2. DXP seems to be beneficial in neurological recovery in terms of histological and oxidative changes after head trauma in rats.
CONCLUSION
DXP should be further evaluated for its possible therapeutic effect in TBI.
PubMed: 38449284
DOI: 10.3340/jkns.2023.0219 -
Biology of Sex Differences Feb 2024Following exposure to traumatic stress, women are twice as likely as men to develop mood disorders. Yet, individual responses to such stress vary, with some people...
BACKGROUND
Following exposure to traumatic stress, women are twice as likely as men to develop mood disorders. Yet, individual responses to such stress vary, with some people developing stress-induced psychopathologies while others exhibit resilience. The factors influencing sex-related disparities in affective disorders as well as variations in resilience remain unclear; however, emerging evidence suggests differences in the gut microbiota play a role. In this study, using the single prolonged stress (SPS) model of post-traumatic stress disorder, we investigated pre- and post-existing differences in microbial composition, functionality, and metabolites that affect stress susceptibility or resilience in each sex.
METHODS
Male and female Sprague-Dawley rats were randomly assigned to control or SPS groups. Two weeks following SPS, the animals were exposed to a battery of behavioral tests and decapitated a day later. Based on their anxiety index, they were further categorized as SPS-resilient (SPS-R) or SPS-susceptible (SPS-S). On the day of dissection, cecum, and selected brain tissues were isolated. Stool samples were collected before and after SPS, whereas urine samples were taken before and 30 min into the SPS.
RESULTS
Before SPS exposure, the sympathoadrenal axis exhibited alterations within male subgroups only. Expression of tight junction protein claudin-5 was lower in brain of SPS-S males, but higher in SPS-R females following SPS. Across the study, alpha diversity remained consistently lower in males compared to females. Beta diversity revealed distinct separations between male and female susceptible groups before SPS, with this separation becoming evident in the resilient groups following SPS. At the genus level, Lactobacillus, Lachnospiraceae_Incertae_Sedis, and Barnesiella exhibited sex-specific alterations, displaying opposing abundances in each sex. Additionally, sex-specific changes were observed in microbial predictive functionality and targeted functional modules both before and after SPS. Alterations in the microbial short-chain fatty acids (SCFAs), were also observed, with major and minor SCFAs being lower in SPS-susceptible males whereas branched-chain SCFAs being higher in SPS-susceptible females.
CONCLUSION
This study highlights distinct pre- and post-trauma differences in microbial composition, functionality, and metabolites, associated with stress resilience in male and female rats. The findings underscore the importance of developing sex-specific therapeutic strategies to effectively address stress-related disorders. Highlights SPS model induces divergent anxiety and social behavioral responses to traumatic stress in both male and female rodents. SPS-resilient females displayed less anxiety-like behavior and initiated more interactions towards a juvenile rat than SPS-resilient males. Sex-specific pre-existing and SPS-induced differences in the gut microbial composition and predictive functionality were observed in susceptible and resilient rats. SPS-resilient males displayed elevated cecal acetate levels, whereas SPS-susceptible females exhibited heightened branched-chain SCFAs.
Topics: Humans; Male; Rats; Female; Animals; Rats, Sprague-Dawley; Resilience, Psychological; Anxiety; Stress Disorders, Post-Traumatic; Brain
PubMed: 38409102
DOI: 10.1186/s13293-024-00590-7 -
International Journal For Parasitology.... Apr 2024In the fall of 2021, California Department of Fish and Wildlife reported larval and adult California giant salamanders ( Eschscholtz, 1833) with skin lesions at multiple...
In the fall of 2021, California Department of Fish and Wildlife reported larval and adult California giant salamanders ( Eschscholtz, 1833) with skin lesions at multiple creeks in Santa Clara and Santa Cruz Counties, California, USA. Field signs in both stages included rough, lumpy textured skin, and larvae with tails that were disproportionately long, flat, wavy, and flaccid. Presence of large-bodied larvae suggested delayed metamorphosis, with some larvae having cloudy eyes and suspected blindness. To determine the cause of the disease, three first-of-the-year salamanders from one location were collected, euthanized with 20% benzocaine, and submitted for necropsy to the U.S. Geological Survey, National Wildlife Health Center. Upon gross examination, all salamanders were emaciated with no internal fat stores, and had multiple pinpoint to 1.5-mm diameter raised nodules in the skin over the body, including the head, gills, dorsum, ventrum, all four limbs, and the tail; one also had nodules in the oral cavity and tongue. Histologically all salamanders had multiple encysted metacercariae in the dermis, subcutis, and skeletal muscles of the head, body, and tail that were often associated with granulomatous and granulocytic inflammation and edema. A small number of encysted metacercariae or empty cysts were present in the gills with minimal inflammation, and rarely in the kidney with no associated inflammation. Morphology of live metacercariae (Trematoda: Heterophyiidae), and sequencing of the 28S rRNA gene identified a species of (Poche, 1926). Artificial digestion of a 1.65 g, decapitated, eviscerated carcass yielded 773 metacercariae, all of similar size and morphology as the live specimens. Based on these findings, the poor body condition of these salamanders was concluded to be due to heavy parasite burden. Environmental factors such as drought, increased temperature, and overcrowded conditions may be exacerbating parasite infections in these populations of salamander.
PubMed: 38405673
DOI: 10.1016/j.ijppaw.2024.100908 -
Plant Physiology May 2024Far-red radiation affects many plant processes, including reproductive organ abortion. Our research aimed to determine the role of apical dominance in far-red...
Far-red radiation affects many plant processes, including reproductive organ abortion. Our research aimed to determine the role of apical dominance in far-red light-induced flower and fruit abortion in sweet pepper (Capsicum annuum L.). We conducted several climate room experiments where plants were grown under white- or red-rich LED light, with or without additional far-red light. Additional far-red light enhanced apical dominance: it increased auxin levels in the apices of dominant shoots, and caused a greater difference in internode length and apical auxin levels between dominant and subordinate shoots. Additional far-red light stimulated fruit abortion in intact plants but not in decapitated plants, suggesting a crucial role of shoot apices in this effect. However, reducing basipetal auxin transport in the stems with N-1-naphthylphthalamic acid did not influence far-red light-stimulated fruit abortion, although auxin levels in the stem were largely reduced. Applying the synthetic auxin 1-naphthaleneacetic acid on decapitated apices did not influence fruit abortion. However, applying the auxin biosynthesis inhibitor yucasin to shoot apices reduced fruit abortion regardless of the light conditions, accompanied by slight shoot growth retardation. These findings suggest that the basipetal auxin stream does not mediate far-red light-stimulated fruit abortion. Far-red light-stimulated fruit abortion was associated with reduced sucrose accumulation and lower invertase activities in flowers. We suggest that under additional far-red light conditions, increased auxin levels in shoot apices promote fruit abortion probably through enhanced competition for assimilates between apices and flowers, which limits assimilate import into flowers.
Topics: Capsicum; Flowers; Fruit; Light; Indoleacetic Acids; Red Light
PubMed: 38366641
DOI: 10.1093/plphys/kiae088 -
International Journal of Legal Medicine Jul 2024Fluid-filled paranasal sinuses are suggested to be a valuable tool to distinguish between drowning and non-drowning postmortem, yet the mechanisms governing fluid entry...
Fluid-filled paranasal sinuses are suggested to be a valuable tool to distinguish between drowning and non-drowning postmortem, yet the mechanisms governing fluid entry remains unknown. We investigate if fluid-filled paranasal sinuses are caused by a passive influx from submersion or an active aspiration mechanism during drowning. The ovine nasal cavity and maxillary sinuses are remarkably similar anatomically to humans, and have been used for endoscopic surgical training in recent decades. We submerged 15 decapitated ovine heads from agricultural waste at a depth of 2 m in flowing water for 1, 8, and 24 h and 7 days. Paranasal sinuses were CT imaged and compared pre- and post-submersion to non-submerged controls. Furthermore, we examined the paranasal sinuses of a single homicide case of a non-drowned submerged subject. Results demonstrate that fluid passively enters the maxillary sinus postmortem in the non-drowned ovine heads following 1 h of submersion. Fluid volume was independent of submersion time and influenced by time out of water as well as handling, since volume was reduced between consecutive CT scans. In contrast to our hypothesis, the filling of the paranasal sinuses is due to passive influx of fluid from submersion rather than an active aspiration during drowning. The observation that paranasal sinuses were fluid-filled in a single medico-legal case of postmortem submersion supports the finding of passive influx. Consequently, careful interpretation of fluid-filled paranasal sinuses is required when bodies are found in water, as the finding cannot distinguish between postmortem submersion and drowning.
Topics: Animals; Drowning; Sheep; Paranasal Sinuses; Models, Animal; Tomography, X-Ray Computed; Immersion; Forensic Pathology; Humans; Postmortem Changes; Maxillary Sinus; Postmortem Imaging
PubMed: 38351206
DOI: 10.1007/s00414-024-03173-8 -
Brain Sciences Jan 2024Alterations in the various neuropeptide systems in the mesocorticolimbic circuitry have been implicated in negative effects associated with drug withdrawal. The...
Alterations in the various neuropeptide systems in the mesocorticolimbic circuitry have been implicated in negative effects associated with drug withdrawal. The corticotropin-releasing factor (CRF) and α-melanocyte-stimulating hormone are two peptides that may be involved. This study investigated the regulatory effects of chronic nicotine exposure and withdrawal on the mRNA levels of melanocortin receptors (MC3R, MC4R), CRF, and CRF receptors (CRFR1 and CRFR2) expressed in the mesocorticolimbic system. Rats were given drinking water with nicotine or without nicotine (control group) for 12 weeks, after which they continued receiving nicotine (chronic exposure) or were withdrawn from nicotine for 24 or 48 h. The animals were decapitated following behavioral testing for withdrawal signs. Quantitative real-time PCR analysis demonstrated that nicotine exposure (with or without withdrawal) increased levels of CRF and CRFR1 mRNA in the amygdala, CRF mRNA in the medial prefrontal cortex, and CRFR1 mRNA in the septum. Nicotine withdrawal also enhanced MC3R and MC4R mRNA levels in different brain regions, while chronic nicotine exposure was associated with increased MC4R mRNA levels in the nucleus accumbens. These results suggest that chronic nicotine exposure and withdrawal regulate CRF and melanocortin signaling in the mesocorticolimbic system, possibly contributing to negative affective state and nicotine addiction.
PubMed: 38248278
DOI: 10.3390/brainsci14010063 -
Inflammopharmacology Apr 2024Putative beneficial effects of neuropeptide W (NPW) in the early phase of gastric ulcer healing process and the involvement of cyclooxygenase (COX) enzymes were...
AIMS
Putative beneficial effects of neuropeptide W (NPW) in the early phase of gastric ulcer healing process and the involvement of cyclooxygenase (COX) enzymes were investigated in an acetic acid-induced gastric ulcer model.
MAIN METHODS
In anesthetized male Sprague-Dawley rats, acetic acid was applied surgically on the serosa and then a COX-inhibitor (COX-2-selective NS-398, COX-1-selective ketorolac, or non-selective indomethacin; 2 mg/kg/day, 3 mg/kg/day or 5 mg/kg/day; respectively) or saline was injected intraperitoneally. One h after ulcer induction, omeprazole (20 mg/kg/day), NPW (0.1 μg/kg/day) or saline was intraperitoneally administered. Injections of NPW, COX-inhibitors, omeprazole or saline were continued for the following 2 days until rats were decapitated at the end of the third day.
KEY FINDINGS
NPW treatment depressed gastric prostaglandin (PG) I2 level, but not PGE2 level. Similar to omeprazole, NPW treatment significantly reduced gastric and serum tumor necrosis factor-alpha and interleukin-1 beta levels and depressed the upregulation of nuclear factor kappa B (NF-κB) and COX-2 expressions due to ulcer. In parallel with the histopathological findings, treatment with NPW suppressed ulcer-induced increases in myeloperoxidase activity and malondialdehyde level and replenished glutathione level. However, the inhibitory effect of NPW on myeloperoxidase activity and NPW-induced increase in glutathione were not observed in the presence of COX-1 inhibitor ketorolac or the non-selective COX-inhibitor indomethacin.
SIGNIFICANCE
In conclusion, NPW facilitated the healing of gastric injury in rats via the inhibition of pro-inflammatory cytokine production, oxidative stress and neutrophil infiltration as well as the downregulation of COX-2 protein and NF-κB gene expressions.
Topics: Animals; Male; Rats; Acetates; Anti-Inflammatory Agents, Non-Steroidal; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Gastric Mucosa; Glutathione; Indomethacin; Ketorolac; Neuropeptides; NF-kappa B; Omeprazole; Peroxidase; Rats, Sprague-Dawley; Signal Transduction; Stomach Ulcer; Ulcer
PubMed: 38227096
DOI: 10.1007/s10787-023-01403-w -
Plants (Basel, Switzerland) Dec 2023Removing the panicle encourages the growth of buds on the elongated node by getting rid of apical dominance. Strigolactones (SLs) are plant hormones that suppress...
Removing the panicle encourages the growth of buds on the elongated node by getting rid of apical dominance. Strigolactones (SLs) are plant hormones that suppress tillering in rice. The present study employed panicle removal (RP) and external application of synthesized strigolactones (GR) to modulate rice bud growth at node 2. We focused on the full-heading stage to investigate proteomic changes related to bud germination (RP-Co) and suppression (GR-RP). A total of 434 represented differentially abundant proteins (DAPs) were detected, with 272 DAPs explicitly specified in the bud germination process, 106 in the bud suppression process, and 28 in both. DAPs in the germination process were most associated with protein processing in the endoplasmic reticulum and ribosome biogenesis. DAPs were most associated with metabolic pathways and glycolysis/gluconeogenesis in the bud suppression process. Sucrose content and two enzymes of sucrose degradation in buds were also determined. Comparisons of DAPs between the two reversed processes revealed that sucrose metabolism might be a key to modulating rice bud growth. Moreover, sucrose or its metabolites should be a signal downstream of the SLs signal transduction that modulates rice bud outgrowth. Contemplating the result so far, it is possible to open new vistas of research to reveal the interaction between SLs and sucrose signaling in the control of tillering in rice.
PubMed: 38202400
DOI: 10.3390/plants13010091 -
Plant Methods Jan 2024The measurement of root dielectric response is a useful non-destructive method to evaluate root growth and function. Previous studies tracked root development throughout...
BACKGROUND
The measurement of root dielectric response is a useful non-destructive method to evaluate root growth and function. Previous studies tracked root development throughout the plant growing cycle by single-time electrical measurements taken repeatedly. However, it is known that root conductivity and uptake activity can change rapidly, coupled with the day/night cycles of photosynthetic and transpiration rate. Therefore, the low-frequency dielectric monitoring of intact root-substrate systems at minute-scale temporal resolution was tested using a customized impedance measurement system in a laboratory environment. Electrical capacitance (C) and conductance (G) and the dissipation factor (D) were detected for 144 h in potted maize, cucumber and pea grown under various light/dark and temperature conditions, or subjected to progressive leaf excision or decapitation. Photosynthetic parameters and stomatal conductance were also measured to evaluate the stress response.
RESULTS
The C and G data series showed significant 24-h seasonality associated with the light/dark and temperature cycles applied. This was attributed to the diurnal patterns in whole-plant transpiration (detected via stomatal conductance), which is strongly linked to the root water uptake rate. C and G decreased during the 6-day dark treatment, and dropped proportionally with increasing defoliation levels, likely due to the loss of canopy transpiration caused by dark-induced senescence or removal of leaves. D showed a decreasing trend for plants exposed to 6-day darkness, whereas it was increased markedly by decapitation, indicating altered root membrane structure and permeability, and a modified ratio of apoplastic to cell-to-cell water and current pathways.
CONCLUSIONS
Dynamic, in situ impedance measurement of the intact root system was an efficient way of following integrated root water uptake, including diurnal cycles, and stress-induced changes. It was also demonstrated that the dielectric response mainly originated from root tissue polarization and current conduction, and was influenced by the actual physiological activity of the root system. Dielectric measurement on fine timescale, as a diagnostic tool for monitoring root physiological status and environmental response, deserves future attention.
PubMed: 38195647
DOI: 10.1186/s13007-023-01133-8