Ethanol Exposure Research Articles

Distinct peroxisome populations differentially respond to alcohol-associated hepatic injury

Although peroxisomes are known to oxidize ethanol, metabolize lipids, and regulate oxidative stress, they remain understudied in the context of ethanol-induced liver injury. We examined peroxisome early responses to alcohol-induced oxidative stress and lipid overload. Analysis of peroxisomes labeled with catalase, an ethanol oxidizing enzyme, or ABCD3, a fatty acid transporter, revealed that distinct peroxisome populations differentially respond to ethanol. We determined that ethanol exposure induced a reversible, time-dependent, saturable increase in functional peroxisomes labeled with either marker. This increase was due to ethanol-induced oxidative stress. In cells treated with oleic acid (to mimic fatty liver), only ABCD3-positive peroxisomes proliferated, and preferentially colocalized with lipid droplets in cells treated with oleic acid alone and/or with ethanol. In cells overexpressing the tubulin-specific acetyltransferase, αTAT1, we determined that peroxisome-lipid droplet contacts were mediated by acetylated microtubules. Peroxisome proliferation was also observed in ethanol-fed mouse and rat livers, but was absent in fibrotic mouse models of liver injury and in samples from individuals with alcohol-induced cirrhosis suggesting that alcohol exposure promotes an early hepatoprotective rise in peroxisomes that is lost as the condition progresses to fibrosis. Our studies further suggest that PPAR agonists may be an effective intervention for early ethanol-associated liver disease.

Polygenic risk for alcohol use disorder affects cellular responses to ethanol exposure in a human microglial cell model.

Polygenic risk scores (PRSs) assess genetic susceptibility to alcohol use disorder (AUD), yet their molecular implications remain underexplored. Neuroimmune interactions, particularly in microglia, are recognized as notable contributors to AUD pathophysiology. We investigated the interplay between AUD PRS and ethanol in human microglia derived from iPSCs from individuals with AUD high-PRS (diagnosed with AUD) or low-PRS (unaffected). Ethanol exposure induced elevated CD68 expression and morphological changes in microglia, with differential responses between high-PRS and low-PRS microglial cells. Transcriptomic analysis revealed expression differences in MHCII complex and phagocytosis-related genes following ethanol exposure; high-PRS microglial cells displayed enhanced phagocytosis and increased CLEC7A expression, unlike low-PRS microglial cells. Synapse numbers in cocultures of induced neurons with microglia after alcohol exposure were lower in high-RPS cocultures, suggesting possible excess synapse pruning. This study provides insights into the intricate relationship between AUD PRS, ethanol, and microglial function, potentially influencing neuronal functions in developing AUD.

Gut microbiota modulates depressive-like behaviors induced by chronic ethanol exposure through short-chain fatty acids

BackgroundChronic ethanol exposure (CEE) is recognized as an important risk factor for depression, and the gut-brain axis has emerged as a key mechanism underlying chronic ethanol exposure-induced anxiety and depression-like behaviors. Short-chain fatty acids (SCFAs), which are the key metabolites generated by gut microbiota from insoluble dietary fiber, exert protective roles on the central nervous system, including the reduction of neuroinflammation. However, the link between gut microbial disturbances caused by chronic ethanol exposure, production of SCFAs, and anxiety and depression-like behaviors remains unclear.MethodsInitially, a 90-day chronic ethanol exposure model was established, followed by fecal microbiota transplantation model, which was supplemented with SCFAs via gavage. Anxiety and depression-like behaviors were determined by open field test, forced swim test, and elevated plus-maze. Serum and intestinal SCFAs levels were quantified using GC-MS. Changes in related indicators, including the intestinal barrier, intestinal inflammation, neuroinflammation, neurotrophy, and nerve damage, were detected using Western blotting, immunofluorescence, and Nissl staining.ResultsChronic ethanol exposure disrupted with gut microbial homeostasis, reduced the production of SCFAs, and led to anxiety and depression-like behaviors. Recipient mice transplanted with fecal microbiota that had been affected by chronic ethanol exposure exhibited impaired intestinal structure and function, low levels of SCFAs, intestinal inflammation, activation of neuroinflammation, a compromised blood-brain barrier, neurotrophic defects, alterations in the GABA system, anxiety and depression-like behaviors. Notably, the negative effects observed in these recipient mice were significantly alleviated through the supplementation of SCFAs.ConclusionSCFAs not only mitigate damage to intestinal structure and function but also alleviate various lesions in the central nervous system, such as neuroinflammation, and reduce anxiety and depression-like behaviors, which were triggered by transplantation with fecal microbiota that had been affected by chronic ethanol exposure, adding more support that SCFAs serve as a bridge between the gut and the brain.

Application of Integrated Optical Density in Evaluating Insulin Expression in the Endocrine Pancreas During Chronic Ethanol Exposure and β-Carotene Supplementation: A Novel Approach Utilizing Artificial Intelligence

Background: β-carotene is an essential antioxidant, providing protection against type 2 diabetes mellitus, cardiovascular illnesses, obesity, and metabolic syndrome. This study investigates the impact of β-carotene on biochemical parameters and pancreatic insulin expression in mice exposed to ethanol. Methods: Thirty-six C57BL/6 mice (Mus musculus) were divided into six groups: 1. C (control), 2. LA (3% alcohol dose), 3. MA (7% alcohol dose), 4. B (0.52 mg/kg body weight/day β-carotene), 5. LA+B (3% alcohol dose + 0.52 mg/kg body weight/day β-carotene), and 6. MA+B (7% alcohol dose plus 0.52 mg/kg body weight/day β-carotene). After 28 days, the animals were euthanized for serum and pancreatic tissue collection. Biochemical analysis and pancreatic insulin expression were performed. One-way ANOVA was used. Results: The B, LA+B, and MA+B groups improved insulin levels and decreased HOMA-β versus the C group, with the LA+B and MA+B groups also showing lower ADH and ALDH levels than their nonsupplemented counterparts (p < 0.05). The B, LA+B, and MA+B groups showed a greater β-cell mass area compared to the unsupplemented groups. Additionally, the LA+B and MA+B groups demonstrated significantly increased β-cell area and integrated optical density compared to the LA and MA groups, respectively (p < 0.001). Conclusions: In mice, β-cell loss led to increased glucose release due to decreased insulin levels. β-carotene appeared to mitigate ethanol’s impact on these cells, resulting in reduced insulin degradation when integrated optical density was used. These findings suggest that antioxidant supplementation may be beneficial in treating ethanol-induced type 2 diabetes in animal models.

Hepatic GPx1 and GIT1 expression altered by ethanol exposure during third trimester-equivalent development

Background Ethanol (EtOH) exposure throughout gestation and breastfeeding leads to multiple adverse outcomes in the hepatic system. Under oxidative stress, alterations in the liver are related to the inhibition of induced nitric oxide synthase activity in sinusoidal cells as a consequence of low expression of G-protein-coupled receptor (GPCR)-kinase interacting (GIT1). Here, we hypothesized that both glutathione peroxidase 1 (GPx1) and GIT1 could be altered by EtOH exposure during the third trimester of human equivalent development. Methods We exposed rats during the third trimester equivalent [postnatal days (PD) 2-8] to moderate levels of maternal EtOH (20%). GPx1 and GIT1 expression was detected by western blotting, and the antioxidant activity of glutathione peroxidase GPx and the concentration of hepatic carbonyl groups (CG were determined by spectrophotometry. Serum biochemistry parameters such as alanine aminotransferase (ALT), glucose (gluc), cholesterol (chol), and triglycerides (TG) were also measured. Results We found that ethanol decreased both GIT1 and GPx1 selenoprotein expression, affecting GPx antioxidant activity and increasing protein oxidation. Conclusions These results demonstrate for the first time that the GPx antioxidant system altered by EtOH exposure during the third trimester of development is related to a parallel decrease in GIT1 expression [1].

Sulforaphane Attenuates Ethanol-Induced Teratogenesis and Dysangiogenesis in Zebrafish Embryos

Prenatal ethanol exposure can cause a broad range of abnormalities in newborns known as Fetal Alcohol Spectrum Disorder (FASD). Despite significant progress in understanding the disease mechanisms of FASD, there remains a strong global need for effective therapies. To evaluate the therapeutic potential of sulforaphane (SFN), an active compound extracted from cruciferous vegetables, in preventing FASD, ethanol-exposed zebrafish embryos were pretreated, co-treated, or post-treated with various concentrations of SFN. The FASD-like morphological features, survival rate, hatching rate, and vascular development were then assessed in the zebrafish embryos. It was found that pretreatment with 2 μM SFN during 3–24 hpf had no noticeable protective effects against teratogenicity induced by subsequent 1.5% ethanol exposure during 24–48 hpf. In contrast, co-treatment with 2 μM SFN and 1.5% ethanol during 3–24 hpf significantly alleviated a range of ethanol-induced malformations, including reduced body length, small eyes, reduced brain size, small otic vesicle, small jaw, and pericardial edema. Post-treatment with 3 μM SFN for 4 days following 1.5% ethanol exposure during 3–24 hpf also significantly reduced the characteristic features of FASD, decreasing the mortality rate and restoring body length, eye size, brain size, and otic vesicle circumference. Moreover, we found that ethanol, even at a low dose (0.5%), causes vascular development deficit in the zebrafish embryos, which were also largely rescued by SFN treatment. These data indicated that SFN has great potential to be used in the prevention and treatment of FASD.

Decreased antioxidant-related superoxide dismutase 1 expression in peripheral immune cells indicates early ethanol exposure

Alcohol consumption increases oxidative stress and imbalances in the antioxidant system, even with ethanol (EtOH) exposure at a young age. This study assessed changes in the antioxidant system following young EtOH exposure in peripheral immunity and measured sensitive indicators of heavy alcohol consumption. We used peripheral blood mononuclear cells (PBMCs) from 197 male university students without smoking habits to examine changes in antioxidant-related gene expression in vitro and in PBMCs. In vitro, the antioxidant system was impaired by EtOH. Next, we examined the expression of 84 antioxidant-related genes in the PBMCs of 162 young adults, among which the superoxide dismutase (SOD) 1 expression was most negatively correlated with alcohol consumption degree. The plasma SOD1 level had the highest area under the curve value (0.806) for heavy alcohol consumption. Our data demonstrated that a decreased SOD1 level is a sensitive indicator of an impaired antioxidant system and heavy alcohol consumption with early EtOH exposure.

Enhanced Fear Extinction Through Infralimbic Perineuronal Net Digestion: The Modulatory Role of Adolescent Alcohol Exposure.

Perineuronal nets (PNNs) are specialized components of the extracellular matrix that play a critical role in learning and memory. In a Pavlovian fear conditioning paradigm, degradation of PNNs affects the formation and storage of fear memories. This study examined the impact of adolescent intermittent ethanol (AIE) exposure by vapor inhalation on the expression of PNNs in the adult rat prelimbic (PrL) and infralimbic (IfL) subregions of the medial prefrontal cortex. Results indicated that following AIE, the total number of PNN positive cells in the PrL cortex increased in layer II/III but did not change in layer V. Conversely, in the IfL cortex, the number of PNN positive cells decreased in layer V, with no change in layer II/III. In addition, the intensity of PNN staining was significantly altered by AIE exposure, which narrowed the distribution of signal intensity, reducing the number of high and low intensity PNNs. Given these changes in PNNs, the next experiment assessed the effects of AIE and PNN digestion on extinction of a conditioned fear memory. In Air control rats, digestion of PNNs by bilateral infusion of Chondroitinase ABC (ChABC) into the IfL cortex enhanced fear extinction and reduced contextual fear renewal. In contrast, both fear extinction learning and contextual fear renewal remained unchanged following PNN digestion in AIE exposed rats. These results highlight the sensitivity of prefrontal PNNs to adolescent alcohol exposure and suggest that ChABC-induced plasticity is reduced in the IfL cortex following AIE exposure.

Voluntary wheel running exercise rescues behaviorally-evoked acetylcholine efflux in the medial prefrontal cortex and epigenetic changes in ChAT genes following adolescent intermittent ethanol exposure.

Adolescent intermittent ethanol (AIE) exposure, which models heavy binge ethanol intake in adolescence, leads to a variety of deficits that persist into adulthood-including suppression of the cholinergic neuron phenotype within the basal forebrain. This is accompanied by a reduction in acetylcholine (ACh) tone in the medial prefrontal cortex (mPFC). Voluntary wheel running exercise (VEx) has been shown to rescue AIE-induced suppression of the cholinergic phenotype. Therefore, the goal of the current study is to determine if VEx will also rescue ACh efflux in the mPFC during spontaneous alternation, attention set shifting performance, and epigenetic silencing of the cholinergic phenotype following AIE. Male and female rats were subjected to 16 intragastric gavages of 20% ethanol or tap water on a two-day on/two-day off schedule from postnatal day (PD) 25-54, before being assigned to either VEx or stationary control groups. In Experiment 1, rats were tested on a four-arm spontaneous alternation maze with concurrent in vivo microdialysis for ACh in the mPFC. An operant attention set-shifting task was used to measure changes in cognitive and behavioral flexibility. In Experiment 2, a ChIP analysis of choline acetyltransferase (ChAT) genes was performed on basal forebrain tissue. It was found that VEx increased ACh efflux in the mPFC in both AIE and control male and female rats, as well as rescued the AIE-induced epigenetic methylation changes selectively at the Chat promoter CpG island across sexes. Overall, these data support the restorative effects of exercise on damage to the cholinergic projections to the mPFC and demonstrate the plasticity of cholinergic system for recovery after alcohol induced brain damage.

Prenatal ethanol exposure impairs hippocampal plasticity and cognition in adolescent mice

BackgroundPrenatal alcohol exposure (PAE) induces a wide range of neurodevelopmental disabilities that are grouped under the term ‘fetal alcohol spectrum disorders’ (FASD). The effects of PAE on brain development are dependent on complex neurochemical events, including modification of AMPA receptors (AMPARs). We have recently found that chronic ethanol (EtOH) exposure decreases AMPA-mediated neurotransmission and expression through the overexpression of the specific microRNA (miR)137 and 501-3p, which target GluA1 AMPA subunit, in the developing hippocampus in vitro. Here, we explored how PAE mice may alter AMPAergic synapses in the hippocampus, and its effects on behavior. MethodsTo model PAE, we exposed C57Bl/6 pregnant mice to 10 % EtOH during during the first 10 days of gestation (GD 0–10; equivalent to the first trimester of pregnancy in humans). AMPA subunits postsynaptic expression in the hippocampus, electrical properties of CA1 neurons, memory recognition, and locomotor functions were then analyzed in adolescent PAE-exposed offspring. ResultsPAE adolescent mice showed dysregulation of AMPAergic neurotransmission, and increased miR 501-3p expression, associated with a significant reduction of spontaneous AMPA currents and intrinsic somatic excitability. In addition, PAE reduced the phosphorylation of AMPAR-containing GluA1 subunit, despite an increase in its total levels. Of note, the total levels of GluA2 and GluA3 AMPA receptors were enhanced as well. Consistently, at behavioral level, PAE reduced object recognition without altering locomotor activity. ConclusionsOur study shows that PAE leads to dysfunctional formation of AMPAergic synapses that could be responsible for neurobehavioral impairments, contributing to the understanding of the pathogenesis of FASD.

Prelimbic cortex perineuronal net expression and social behavior: Impact of adolescent intermittent ethanol exposure

Adolescent intermittent ethanol (AIE) exposure in rats leads to social deficits. Parvalbumin (PV) expressing fast-spiking interneurons in the prelimbic cortex (PrL) contribute to social behavior, and perineuronal nets (PNNs) within the PrL preferentially encompass and regulate PV interneurons. AIE exposure increases PNNs, but it is unknown if this upregulation contributes to AIE-induced social impairments. The current study was designed to determine the effect of AIE exposure on PNN expression in the PrL and to assess whether PNN dysregulation contributes to social deficits elicited by AIE. cFos-LacZ male and female rats were exposed every other day to tap water or ethanol (4 g/kg, 25% w/v) via intragastric gavage between postnatal day (P) 25–45. We evaluated neuronal activation by β-galactosidase expression and PNN levels either at the end of the exposure regimen on P45 and/or in adulthood on P70. In addition, we used Chondroitinase ABC (ChABC) to deplete PNNs following adolescent exposure (P48) and allowed for PNN restoration before social testing in adulthhod. AIE exposure increased PNN expression in the PrL of adult males, but decreased PNNs immediately following AIE. Vesicular glutamate transporter 2 (vGlut2) and vesicular GABA transporter (vGat) near PNNs were downregulated only in AIE-exposed females. Gene expression of PNN components was largely unaffected by AIE exposure. Removal and reestablishment of PrL PNNs by ChABC led to upregulation of PNNs and social impairments in males, regardless of adolescent exposure. These data suggest that AIE exposure in males upregulates PrL PNNs that likely contribute to social impairments induced by AIE.

Curcumin attenuates smoking and drinking activated NF-κB/IL-6 inflammatory signaling axis in cervical cancer

BackgroundHigh-risk strains of HPV are known to cause cervical cancer. Multiple clinical studies have emphasized that smoking and drinking are critical risk factors for cervical cancer and its high-grade precursors. In this study, we investigated if smoking and/or drinking augment the molecular mechanisms of cervical carcinogenesis and defined a potential therapeutic approach for their attenuation.MethodsThe impact of benzo[a]pyrene (B[a]P) and/or ethanol (EtOH) exposure on cervical cancer cells was assessed by measuring changes in their cell migration and invasion characteristics. Expression of HPV16 E6/E7, NF-κB, cytokines, and inflammation mediators was determined using qRT-PCR, immunoblotting, ELISA, luciferase reporter assay, and confocal microscopy. Herein, we used curcumin (Cur), and PLGA nanoparticle formulation of curcumin (PLGA-Cur) and determined effectiveness of free Cur and PLGA-Cur formulation on smoking and drinking activated NF-κB/IL-6 mediated inflammatory signaling pathways using in vitro cervical cancer models.ResultsTreatments with B[a]P and/or EtOH altered the expression of HPV16 E6/E7 oncogenes and EMT markers in cervical cancer cells; it also enhanced migration and invasion. In addition, B[a]P and/or EtOH exposure promoted inflammation pathways through TNF-α and NF-κB signaling, leading to IL-6 upregulation and activation of VEGF. The molecular effects caused by B[a]P and/or EtOH exposure were effectively attenuated by curcumin (Cur)/PLGA-Cur treatment.ConclusionsThese data suggest a molecular link between smoking, drinking, and HPV infectivity in cervical carcinogenesis. In addition, attenuation of these effects by treatment with Cur/PLGA-Cur treatment, implies the role of curcumin in cervical cancer prevention and treatment.

Chronic Ethanol Exposure Produces Sex-Dependent Impairments in Value Computations in the Striatum.

Value-based decision-making relies on the striatum, where neural plasticity can be altered by chronic ethanol (EtOH) exposure, but the effects of such plasticity on striatal neural dynamics during decision-making remain unclear. This study investigated the long-term impacts of EtOH on reward-driven decision-making and striatal neurocomputations in male and female rats using a dynamic probabilistic reversal learning task. Following a prolonged withdrawal period, EtOH-exposed male rats exhibited deficits in adaptability and exploratory behavior, with a preference for value updating based on rewards rather than omissions. These behavioral changes were linked to altered neural encoding in the dorsomedial striatum (DMS), where EtOH increased outcome-related signals and decreased choice-related signals. In contrast, female rats showed minimal behavioral changes with distinct EtOH-evoked alterations of neural signals, revealing significant sex differences in the impact of chronic EtOH. Our findings underscore the profound impact of chronic EtOH exposure on adaptive decision-making, revealing enduring changes in neurocomputational processes in the striatum underlying cognitive deficits that differ by sex.

Effect of chronic alcohol exposure and single-prolonged stress on conditioned fear behavior

The present study investigated the impact of chronic intermittent ethanol (CIE) exposure and single-prolonged stress (SPS) on the acquisition of fear memories in both male and female Wistar rats. Adult rats were first subjected to CIE by vapor inhalation followed by SPS. Following a subsequent 8-day incubation period, the rats underwent a Pavlovian fear conditioning procedure (tone-shock pairings) followed by cued-tone extinction training, and then testing of extinction recall memory and fear renewal memory. In control animals that had not been exposed to either CIE or SPS, female rats exhibited significantly lower levels of freezing compared to male rats during tone-shock pairings. This lower level of freezing in female rats during conditioning was associated with an increased speed of movement compared to males. Also compared to males, female rats exhibited lower levels of fear extinction, recall, and renewal. Exposure to CIE, SPS, or CIE+SPS had no effect on freezing during the cued-conditioning, extinction, or extinction recall phases of the testing procedure in either sex. In fear renewal, CIE exposure decreased freezing in male but not female rats, while SPS increased freezing in female but not male rats. CIE exposure significantly reduced freezing during the fear renewal phase. Taken together, these results provide further evidence that male and female rats adopt different avoidance strategies for threat responding. These results also revealed that prior exposure to CIE, SPS, or CIE+SPS had minimal effects on threat responding using conditioned freezing as an indicator of fear responsivity.

Separate mechanisms regulating accumbal taurine levels during baseline conditions and following ethanol exposure in the rat

Ethanol-induced dopamine release in the nucleus accumbens (nAc) is associated with reward and reinforcement, and for ethanol to elevate nAc dopamine levels, a simultaneous increase in endogenous taurine is required within the same brain region. By employing in vivo microdialysis in male Wistar rats combined with pharmacological, chemogenetic and metabolic approaches, our aim with this study was to identify mechanisms underlying ethanol-induced taurine release. Our results demonstrate that the taurine elevation, elicited by either systemic or local ethanol administration, occurs both in presence and absence of action potential firing or NMDA receptor blockade. Inhibition of volume regulated anion channels did not alter the ethanol-induced taurine levels, while inhibition of the taurine transporter occluded the ethanol-induced taurine increase, putatively due to a ceiling effect. Selective manipulation of nAc astrocytes using Gq-coupled designer receptors exclusively activated by designer drugs (DREADDs) did not affect ethanol-induced taurine release. However, activation of Gi-coupled DREADDs, or metabolic inhibition using fluorocitrate, rather enhanced than depressed taurine elevation. Finally, ethanol-induced taurine increase was fully blocked in rats pre-treated with the L-type Ca2+-channel blocker nicardipine, suggesting that the release is Ca2+ dependent. In conclusion, while astrocytes appear to be important regulators of basal taurine levels in the nAc, they do not appear to be the main cells underlying ethanol-induced taurine release.

Low to moderate ethanol exposure reduces astrocyte-induced neuroinflammatory signaling and cognitive decline in presymptomatic APP/PS1 mice

Alcohol use disorder has been associated with the development of neurodegenerative diseases, including Alzheimer’s disease (AD). However, recent studies demonstrate that moderate alcohol consumption may be protective against dementia and cognitive decline. We examined astrocyte function, low-density lipoprotein (LDL) receptor-related protein 1 (LRP1), and the NF-κB p65 and IKK-α/β signaling pathways in modulating neuroinflammation and amyloid beta (Aβ) deposition. We assessed apolipoprotein E (ApoE) in the brain of APP/PS1 mice using IHC and ELISA in response to low to moderate ethanol exposure (MEE). First, to confirm the intracerebral distribution of ApoE, we co-stained with GFAP, a marker for astrocytes that biosynthesize ApoE. We sought to investigate whether the ethanol-induced upregulation of LRP1 could potentially inhibit the activity of IL-1β and TNF-α induced IKK-α/β towards NF-κB p65, resulting in a reduction of pro-inflammatory cytokines. To evaluate the actual Aβ load in the brains of APP/PS1 mice, we performed with a specific antibody Aβ (Thioflavin S) on both air- and ethanol-exposed groups, subsequently analyzing Aβ levels. We also measured glucose uptake using 18F- fluorodeoxyglucose (FDG)-positron emission tomography (PET). Finally, we investigated whether MEE induced cognitive and memory changes using the Y maze, noble object recognition test, and Morris water maze. Our findings demonstrate that MEE reduced astrocytic glial fibrillary acidic protein (GFAP) and ApoE levels in the cortex and hippocampus in presymptomatic APP/PS1 mice. Interestingly, increased LRP1 protein expression was accompanied by dampening the IKK-α/β-NF-κB p65 pathway, resulting in decreased IL-1β and TNF-α levels in male mice. Notably, female mice show reduced levels of anti-inflammatory cytokines IL-4, and IL-10 without altering IL-1β and TNF-α concentrations. In both males and females, Aβ plaques, a hallmark of AD, were reduced in the cortex and hippocampus of APP/PS1 mice exposed to ethanol starting at pre-symptomatic stage. Consistently, MEE increased FDG-PET-based brain activities and normalized cognitive and memory deficits in the APP/PS1 mice. Our findings suggest that MEE may benefit AD pathology via modulating LRP1 expression, potentially reducing neuroinflammation and attenuating Aβ deposition. Our study implies that reduced astrocyte-derived ApoE and LDL cholesterol levels are critical for attenuating AD pathology.

Stem extract from Costus afer (Bush cane) prevents ethanol-induced neuronal degeneration in mice via an antioxidant-inflammatory pathway

BackgroundExcessive alcohol consumption is associated with memory impairment and can lead to Alzheimer's disease-like dementia, contributing to the rising prevalence of dementia worldwide. Costus afer (Bush cane) is a medicinal plant widely used in traditional African medicine for its anti-inflammatory, antioxidant, and neuroprotective properties. It is commonly employed to treat various ailments, including inflammatory diseases, respiratory conditions, and gastrointestinal disorders. PurposeGiven its traditional use in the treatment of kyphosis (hunchback) which is implicated in cerebral palsy and degenerative disease of the spine, we explored its potential neuroprotective effects against ethanol-induced neuronal degeneration, in this research, we examined the potential protective impacts on memory and neurology afforded by the aqueous stem extract derived from C. afer in mice subjected to ethanol exposure. MethodsForty-five male Swiss mice weighing 22–35 g were divided into five groups (n = 9): control (treated with distilled water orally), memory-impaired (treated with ethanol at 5 g/kg orally), and three groups treated with ethanol followed by administration of C. afer at doses of 100 mg/kg, 200 mg/kg, and 500 mg/kg respectively. All animals were provided unrestricted access to both food and water throughout the duration of the study. Memory impairment was assessed after 28 days using the T-maze spontaneous alternation test. Subsequently, spectrophotometry, ELISA, and histomorphometry were employed to evaluate indicators of neuronal inflammation, oxidative stress linked to inflammation, and degenerative changes were assessed in the hippocampus, prefrontal cortex, and cerebellum. ResultsEthanol administration led to a notable (p < 0.01) decline in neurobehavioral function, as evidenced by reduced spontaneous alternation behavior, which was mitigated by C. afer treatment, leading to increased percentage alternation. Furthermore, ethanol administration altered endogenous antioxidant levels and pro-inflammatory mediators, resulting in elevated lipid peroxidation, nitrite, tumor necrosis factor-alpha, interleukin-6, and decreased superoxide dismutase activity, promoting neuronal degeneration in the mice brains. However, treatment with C. afer at doses of 100 mg/kg, 200 mg/kg, and 500 mg/kg substantially (p < 0.05) attenuated oxidoinflammatory stress by reducing levels of MDA, NO-2, TNF-α, IL-6, while upregulating SOD activity, thereby preserving neuronal integrity in the hippocampus, prefrontal cortex, and cerebellum. ConclusionThese findings suggest that C. afer mitigates the progression of memory impairment induced by ethanol through mechanisms involving the suppression of oxidoinflammatory stress facilitators and inhibition of cortico-hippocampal and cerebellar neuronal degeneration in murine subjects.

Foxe1 mutant zebrafish show indications of a hypothyroid phenotype and increased sensitivity to ethanol for craniofacial malformations.

FOXE1 mutations in humans are associated with cleft palate and hypothyroidism. We previously developed a foxe1 mutant zebrafish demonstrating mineralization defects in larvae. In the present study, we investigate the thyroid status and skeletal phenotype of adult foxe1 mutants. Mutant fish have increased expression of tshβ in the pituitary, and of hepatic dio1 and dio2. In plasma, we found higher Mg levels. Together these findings are indicative of hypothyroidism. We further observed mineralization defects in scales due to enhanced osteoclast activity as measured by increased expression levels of tracp, ctsk, and rankl. Gene-environment interactions in the etiology of FOXE1-related craniofacial abnormalities remain elusive, which prompts the need for models to investigate genotype-phenotype associations. We here investigated whether ethanol exposure increases the risk of developing craniofacial malformations in foxe1 mutant larvae that we compared to wild types. We found in ethanol-exposed mutants an increased incidence of developmental malformations and marked changes in gene expression patterns of cartilage markers (sox9a), apoptotic markers (casp3b), retinoic acid metabolism (cyp26c1), and tissue hypoxia markers (hifaa, hifab). Taken together, this study shows that the foxe1 mutant zebrafish recapitulates phenotypes associated with FOXE1 mutations in human patients and a clear foxe1-ethanol interaction.

B-260 Prevalence and Relative Distributions of Major Phosphatidylethanol (PEth) Homologs in a Large-Scale Clinical Study

Abstract Background Ethanol abuse remains a significant public health challenge in the United States. Detection of ethanol exposure is crucial for preventive, diagnostic, and therapeutic endeavors. Phosphatidylethanol (PEth) is a specific and direct ethanol biomarker. Compared to other metabolites, such as ethyl glucuronide and ethyl sulfate in urine (average 2-3 days), PEth in blood has a longer window of detection (average 1-2 weeks). Among the known 48 PEth homologs, PEth 16:0/18:1 (POPEth) and PEth 16:0/18:2 (PLPEth) are the most abundant species accounting for 37% to 46% and 26% to 28%, respectively. PLPEth is synthesized at a greater rate than POPEth, but POPEth has a longer half-life than PLPEth. The purpose of this study was to understand the prevalence and levels of POPEth and PLPEth in a large number of clinical specimens. Methods Briefly, lavender-top whole blood specimens were diluted with isotopically labeled internal standard (IS) in an organic buffer to precipitate proteins on an automated Hamilton platform. The mixture was centrifuged, and a supernatant portion isolated for injection onto a Sciex QTRAP 5500 liquid chromatography tandem mass spectrometry (LC-MS/MS) system using electrospray ionization (ESI) in negative mode. The assay was fully validated under CLIA regulations for lab developed tests: the analytical measurement range (AMR) was 10-400 ng/mL; the administrative reporting threshold for PEth positivity was 20 ng/mL based on clinical literature and a consensus among other United States laboratory methods. Results Precision of 4 QC levels was evaluated with between-run CV% (n=25) ranging from 1.6-6.3%, and accuracy across the AMR was achieved with 87-110%. No significant matrix effects were observed; variation in different whole blood specimens was corrected with IS normalization. No significant interferences were observed from 137 commonly seen prescription and nonprescription drugs and 6 other PEth homologs. Of the clinical specimens, most (20,833, 71.3%) were negative (&amp;lt;20 ng/mL) for both analytes. Meanwhile, 8,222 specimens (28.3%) were positive with either POPEth, or PLPEth or both ≥ 20ng/mL. There were 150 specimens excluded from the statistics due to interference challenges. Interestingly, 757 specimens (2.6%) were PLPEth negative and POPEth positive (mean value 40.1 ng/mL). Conversely, 62 specimens (0.2%) were POPEth negative and PLPEth positive (mean value 24.6 ng/mL). Among the specimens with both POPEth and PLPEth levels within the AMR, the average POPEth/PLPEth ratio was 1.4 supporting the overall prevalence of higher POPEth concentrations than PLPEth. However, the POPEth/PLPEth ratio varied widely, from 0.3 to 8.8, reflecting patient differences in PEth metabolism patterns. Conclusions To help verify probable ethanol abstinence, we have developed, validated, and deployed a high-throughput clinical assay for the major PEth homologs, POPEth and PLPEth. In a retrospective analysis of 29,205 clinical specimens: 71.3% of results were consistent with abstinence; 28.3% of the results were positive suggesting moderate alcohol consumption within the last 1-2 weeks. With POPEth most prevalent, yet variation observed, there were 62 specimens with PLPEth positive and negative for POPEth. This clinical PEth study including both POPEth and PLPEth provides greater sensitivity to identify ethanol exposure than only testing a single homolog.

Chronic ethanol exposure in mice evokes pre- and postsynaptic deficits in GABAergic transmission in ventral tegmental area GABA neurons.

GABAergic neurons in mouse ventral tegmental area (VTA) exhibit elevated activity during withdrawal following chronic ethanol exposure. While increased glutamatergic input and decreased GABAA receptor sensitivity have been implicated, the impact of inhibitory signaling in VTA GABA neurons has not been fully addressed. We used electrophysiological and ultrastructural approaches to assess the impact of chronic intermittent ethanol vapour exposure in mice on GABAergic transmission in VTA GABA neurons during withdrawal. We used CRISPR/Cas9 ablation to mimic a somatodendritic adaptation involving the GABAB receptor (GABABR) in ethanol-naïve mice to investigate its impact on anxiety-related behaviour. The frequency of spontaneous inhibitory postsynaptic currents was reduced in VTA GABA neurons following chronic ethanol treatment and this was reversed by GABABR inhibition, suggesting chronic ethanol strengthens the GABABR-dependent suppression of GABAergic input to VTA GABA neurons. Similarly, paired-pulse depression of GABAA receptor-dependent responses evoked by optogenetic stimulation of nucleus accumbens inputs from ethanol-treated mice was reversed by GABABR inhibition. Somatodendritic currents evoked in VTA GABA neurons by GABABR activation were reduced following ethanol exposure, attributable to the suppression of GIRK (Kir3) channel activity. Mimicking this adaptation enhanced anxiety-related behaviour in ethanol-naïve mice. Chronic ethanol weakens the GABAergic regulation of VTA GABA neurons in mice via pre- and postsynaptic mechanisms, likely contributing to their elevated activity during withdrawal and expression of anxiety-related behaviour. As anxiety can promote relapse during abstinence, interventions targeting VTA GABA neuron excitability could represent new therapeutic strategies for treatment of alcohol use disorder.