Alcohol-induced Apoptosis Research Articles

Mechanisms of Differential Sensitivity to Ethanol-Induced Apoptosis in Mouse Spinal Cord at Different Developmental Stages-Akt/GSK Signaling and BAX.

The current study investigated differences in ethanol-induced apoptosis of spinal cord dorsal horn neurons at different developmental stages and the molecular mechanisms involved. A mouse ethanol intervention model was established on postnatal days 4, 7, and 12. Primary cells were derived from the spinal cord at postnatal day 4. Western blotting, immunofluorescence, and flow cytometry were used to detect apoptosis-related proteins in the spinal cord and primary cells. Kyoto Encyclopedia of Genes and Genomes enrichment analysis of differentially expressed genes originating from the Gene Expression Omnibus dataset GSE184615 was conducted. Effects on Akt/GSK3β pathway proteins were investigated using the GSK3β inhibitor AR-A014418, and the Akt inhibitor DHA. Lentiviral knockdown and overexpression of intervening GSK3β were used in HT22 cell lines to investigate the effects of alcohol on GSK 3β and caspase proteins. J-aggregates, reactive oxygen species assays, and calcein-AM assays were used to investigate mitochondrial function and cell viability. Ethanol caused downregulation of Akt activity and upregulation of GSK3β activity and apoptosis. DHA, AR-A014418, and knockdown of GSK3β effectively counteracted ethanol-induced apoptosis, whereas overexpression of GSK3β enhanced the injury process. PI3K activity was unchanged during these processes. Fluorescence colocalization analysis indicated that BAX was translocated to mitochondria during the apoptotic process. BAX was downregulated as the spinal cord developed, consistent with a reduced susceptibility to ethanol-induced apoptosis. Akt/GSK3β signaling and BAX together determine the direction of alcohol-induced apoptosis and its susceptibility to change during developmental stages in the spinal cord.

Clam-derived exosome-like nanovesicles alleviate alcohol-induced liver injury by improving mitochondrial function

Alcoholic liver disease (ALD) is a common chronic liver disease worldwide that urgently needs safe and effective strategies. Clams are popular seafood with hepatoprotective effects, while the effective components and mechanisms remain unclear. Herein, we demonstrated that clam-derived exosome-like nanovesicles (CENs) ameliorated alcohol-induced liver injury by preventing mitochondrial dysfunction and inhibiting mitochondrial apoptotic pathway. Results showed that CENs exhibited exosome-like morphology with a particle size of 120.08 ± 1.60 nm. Mass spectrometry revealed that CENs naturally carry multiple functional lipids and proteins. Furthermore, CENs were found to survive in the gastrointestinal environment and accumulate in the liver of mice following oral administration. Importantly, administration of CENs effectively alleviated alcohol-induced liver injury and hepatocyte death in mice by restoring mitochondrial function, as indicated by increased ATP levels, enhanced mitochondrial complex I activity, and reduced mitochondrial ROS production. Further cell experiments indicated that CENs could be phagocytosed by HepG2 cells and effectively alleviated alcohol-induced hepatocyte apoptosis by inhibiting mitochondrial apoptotic pathway. Collectively, these results indicate that CENs possess potent hepatoprotective properties and may serve as a novel functional ingredient for managing alcoholic liver disease.

Laurus nobilis L. leaves Suppress Alcohol-Related Liver Disease by Exhibiting Antioxidant and Anti-Inflammatory Effects in Alcohol-Treated Hepatocytes and Mice.

Excessive and prolonged alcohol consumption can lead to a serious health condition known as alcohol-related liver disease (ARLD). This ailment represents a significant worldwide health challenge, affecting populations across various demographics. ARLD has a multifactorial pathogenesis involving oxidative stress, inflammation, dysregulated lipid metabolism, and apoptosis. In this study, we investigated the hepatoprotective effects of Laurus nobilis L. leaf water extract (LLE) against ARLD in alcohol-treated hepatocytes and mice. LLE exhibited antioxidant and anti-inflammatory properties by enhancing antioxidant enzyme activities and suppressing proinflammatory cytokines and CYP2E1 expression in ethanol-treated hepatocytes. Moreover, LLE mitigated lipogenesis by modulating the expression of lipogenic factors in ethanol-treated hepatocytes. In vivo, LLE administration attenuated liver injury, oxidative stress, inflammation, and lipid accumulation induced by alcohol consumption in mice. Additionally, LLE suppressed apoptosis signaling pathways implicated in alcohol-induced hepatocyte apoptosis. These findings suggest that LLE functions as a multifaceted therapeutic agent for ARLD by modulating multiple cellular mechanisms, including the reduction of oxidative damage, mitigation of inflammatory responses, alleviation of lipid-mediated toxicity, and regulation of programmed cell death pathways.

Active Components of Pueraria lobata through the MAPK/ERK Signaling Pathway Alleviate Iron Overload in Alcoholic Liver Disease.

To delve into the primary active ingredients and mechanism of Pueraria lobata for alleviating iron overload in alcoholic liver disease. Pueraria lobata's potential targets and signaling pathways in treating alcohol-induced iron overloads were predicted using network pharmacology analysis. Then, animal experiments were used to validate the predictions of network pharmacology. The impact of puerarin or genistein on alcohol-induced iron accumulation, liver injury, oxidative stress, and apoptosis was assessed using morphological examination, biochemical index test, and immunofluorescence. Key proteins implicated in linked pathways were identified using RT-qPCR, western blot analysis, and immunohistochemistry. Network pharmacological predictions combined with animal experiments suggest that the model group compared to the control group, exhibited activation of the MAPK/ERK signaling pathway, suppression of hepcidin expression, and aggravated iron overload, liver damage, oxidative stress, and hepatocyte death. Puerarin and genistein, the active compounds in Pueraria lobata, effectively mitigated the aforementioned alcohol-induced effects. No statistically significant disparities were seen in the effects above between the two groups receiving drug therapy. This study preliminarily demonstrated that puerarin and genistein in Pueraria lobata may increase hepcidin production to alleviate alcohol-induced iron overload by inhibiting the MAPK/ERK signaling pathway.

Lactobacillus plantarum ST-III culture supernatant protects against acute alcohol-induced liver and intestinal injury.

The beneficial effects of probiotics have been studied in inflammatory bowel disease, nonalcoholic steatohepatitis, and alcoholic liver disease (ALD). Probiotic supplements are safer and more effective; however, their potential mechanisms are unclear. An objective of the current study was to examine the effects of extracellular products of Lactobacillus plantarum on acute alcoholic liver injury. Mice on a standard chow diet were supplemented with Lactobacillus plantarum ST-III culture supernatant (LP-cs) for two weeks and administered alcohol at 6 g/kg body weight by gavage. Alcohol-induced liver injury was assessed by measuring plasma alanine aminotransferase activity levels and triglyceride content determined liver steatosis. Intestinal damage and tight junctions were assessed using histochemical staining. LP-cs significantly inhibited alcohol-induced fat accumulation, inflammation, and apoptosis by inhibiting oxidative stress and endoplasmic reticulum stress. LP-cs significantly inhibited alcohol-induced intestinal injury and endotoxemia. These findings suggest that LP-cs alleviates acute alcohol-induced liver damage by inhibiting oxidative stress and endoplasmic reticulum stress via one mechanism and suppressing alcohol-induced increased intestinal permeability and endotoxemia via another mechanism. LP-cs supplements are a novel strategy for ALD prevention and treatment.

Alcohol Intake Provoked Cardiomyocyte Apoptosis Via Activating Calcium-Sensing Receptor and Increasing Endoplasmic Reticulum Stress and Cytosolic [Ca2+]i.

Cardiomyocyte apoptosis plays an important role in alcoholic cardiac injury. However, the association between calcium-sensing receptor (CaSR) and alcohol-induced cardiomyocyte apoptosis remain unclear. Therefore, we investigated the role and its moleculer mechanism of CaSR in rat cardiomyocyte apoptosis induced by alcohol. Alcohol-induced cardiomyocyte apoptosis in vivo and in vitro model of rats were applied in this study. The expression of CaSR, endoplasmic reticulum stress markers and apoptosis were tested by immunohistological staining, western blot, TUNEL and flow cytometry, respectively. [Ca2+]i were detected by confocal laser scanning microscopy. Compared with the control group, alcohol intake (AI) led to abnormal arrangements of cardiomyocytes and obvious increase of myocardial apoptosis. Moreover, AI also significantly upregulated protein expression of CaSR, GRP94, caspase-12 and CHOP. Alcohol induced apoptosis of cultured cardiomyocytes of rats in a dose-dependent way. Activation of CaSR markedly enhanced cardiomyocyte apoptosis and ERS induced by alcohol, ERS inducer also significantly increased cardiomyocyte apoptosis without activating CaSR. Furthermore, GdCl3 augmented alcohol-induced increase of [Ca2+]i in cardiomyocytes, which was attenuated by NPS2390 but not 4-PBA pre-treatment. Alcohol could induce cardiomyocyte apoptosis in rats in vivo and in vitro, which was mediated probably via activating CaSR, and then ERS and the increase of the cytosolic [Ca2+]i. This provides a potential target for preventing cardiomyocyte apoptosis and cardiomyopathy induced by alochol.

Role of ERK1/2 Signaling in Cinnabarinic Acid-Driven Stanniocalcin 2-Mediated Protection against Alcohol-Induced Apoptosis.

We have previously shown that a bona fide aryl hydrocarbon receptor (AhR) agonist, cinnabarinic acid (CA), protects against alcohol-induced hepatocyte apoptosis via activation of a novel AhR target gene, stanniocalcin 2 (Stc2). Stc2 translates to a secreted disulfide-linked hormone, STC2, known to function in cell development, calcium and phosphate regulation, angiogenesis, and antiapoptosis-albeit the comprehensive mechanism by which the CA-AhR-STC2 axis confers antiapoptosis is yet to be characterized. In this study, using RNA interference library screening, downstream antiapoptotic molecular signaling components involved in CA-induced STC2-mediated protection against ethanol-induced apoptosis were investigated. RNA interference library screening of kinases and phosphatases in Hepa1 cells and subsequent pathway analysis identified mitogen-activated protein kinase (MAPK) signaling as a critical molecular pathway involved in CA-mediated protection. Specifically, phosphorylation of ERK1/2 was induced in response to CA treatment without alterations in p38 and JNK signaling pathways. Silencing Stc2 in Hepa1 cells and in vivo experiments performed in Stc2-/- (Stc2 knockout) mice, which failed to confer CA-mediated protection against ethanol-induced apoptosis, showed abrogation of ERK1/2 activation, underlining the significance of ERK1/2 signaling in CA-STC2-mediated protection. In conclusion, activation of ERK1/2 signaling in CA-driven AhR-dependent Stc2-mediated protection represents a novel mechanism of protection against acute alcohol-induced apoptosis. SIGNIFICANCE STATEMENT: Previous studies have shown the role of stanniocalcin 2 (Stc2) in cinnabarinic acid (CA)-mediated protection against alcohol-induced apoptosis. Here, using RNA interference library screening and subsequent in vivo studies, the functional significance of ERK1/2 activation in CA-induced Stc2-mediated protection against acute ethanol-induced apoptosis was identified. This study is thus significant as it illustrates a comprehensive downstream mechanism by which CA-induced Stc2 protects against alcoholic liver disease.

MiR-96-5p is involved in alcohol-induced apoptosis in PC12 cells via negatively regulating TAp73.

The present study opted for the adrenal phaeochromocytoma (PC12) cell line to frame a neuronal injury model induced by alcohol exposure in vitro, aiming to probe whether TAp73 and miR-96-5p are involved in the neuronal injury process induced by alcohol and elucidate the regulatory relationship between miR-96-5p and TAp73. Immunofluorescence staining was used to observe the structural features of PC12 cells after culturing in medium with nerve growth factor (NGF). After different doses and different durations of alcohol treatment, CCK-8 assay was performed to detect the viability of PC12 cells, flow cytometry assay was carried out to detect the apoptosis rate of PC12 cells, dual-luciferase reporter assay was used to definitude the regulatory relationship between miR-96-5p and Tp73, and western blot was used to detect the protein expression of TAp73. The result of immunofluorescence staining demonstrated that PC12 cells abundantly expressed Map2, CCK-8 assay illustrated alcohol exposure significantly downregulated the cell viability of PC12 cells, Treatment with miR-96-5p inhibitor induced apoptosis and upregulated the expression of TAp73 in PC12 cells. Contrastingly, miR-96-5p mimic reversed the above effects and downregulation of TAp73 inhibited the apoptosis of PC12 cells. The present study demonstrated that miR-96-5p participates in alcohol-induced apoptosis in PC12 cells via negatively regulating TAp73.

Cardioprotective Effects of 6-Gingerol against Alcohol-Induced ROS-Mediated Tissue Injury and Apoptosis in Rats.

The present study investigated the cardioprotective properties of 6-gingerol against alcohol-induced ROS-mediated cardiac tissue damage in rats. Experiments were conducted on 4 groups of rats, orally treated with control, 6-gingerol (10 mg/kg body weight), alcohol (6 g/kg body weight) and combination of 6-gingerol plus alcohol for two-month. In the results, we found 6-ginger treatment to alcohol-fed rats substantially suppressed ROS production in cardiac tissue. Alcohol-induced elevated 8-OHDG and protein carbonyls which represent oxidative modification of DNA and proteins were completely reversed by 6-gingerol. This was further endorsed by restored superoxide dismutase and catalase activities with 6-gingerol against alcohol-induced loss. The elevated cardiac biomarkers (CK-MB, cTn-T, cTn-I) and dyslipidemia in alcohol-intoxicated rats was significantly reversed by 6-gingerol. Furthermore, alcohol-induced apoptosis characterized by overexpression of cytochrome C, caspase-8 and caspase-9 was diminished with 6-gingerol treatment. Transmission electron microscope images conferred the cardioprotective properties of 6-gingerol as we have seen less structural derangements in mitochondria and reappearance of myofilaments. Our findings conclude that 6-ginger effectively protect alcohol-induced ROS-mediated cardiac tissue damage, which may be due to its potent antioxidant efficacy. Therefore, 6-gingerol could be a potential therapeutic molecule that can be used in the treatment of alcohol-induced myocardial injury.

Centranthera grandiflore alleviates alcohol-induced oxidative stress and cell apoptosis.

Alcohol liver disease (ALD) has become a global threat to human health. It is associated with a wide range of liver diseases including alcohol fatty liver, steatosis, fibrosis and cirrhosis, and finally leads to liver cancer and even death. Centranthera grandiflora is a traditional Chinese medicinal herb commonly used to treat ALD, but no research about its mechanism is available. This study evaluated the hepatoprotective effect and mechanism of C. grandiflora against alcohol-induced liver injury in mice. We found that the ethanol extracts of C. grandiflora (CgW) alleviated the alcohol-induced liver injury, enhanced the levels of antioxidant enzymes, and reduced the amount of lipid peroxides. CgW also affected cell apoptosis by inhibiting the activity of Bax, cleaved-caspase 3 and cleaved-caspase 9, and increasing the activity of Bcl-2. In conclusion, the results showed that CgW can effectively improve ALD through alleviating oxidative stress and inhibiting cell apoptosis for the first time. This study suggested that C. grandiflora is a promising herbal medicine for ALD treatment.

Baicalin confers hepatoprotective effect against alcohol-associated liver disease by upregulating microRNA-205

Recently, baicalin refers to flavonoid compound extracted from Scutellaria baicalensis Georgi has been indicated to hold promising therapeutic effects in alcohol-associated liver disease (ALD). However, knowledge of the molecular mechanisms for its hepatoprotective effect is still very limited. Evidence exists suggesting potential association between miR-205 and baicalin’s function. Bioinformatic analysis and dual luciferase reporter assay were conducted to determine the binding affinity between miR-205 and importinα5. Our findings revealed that baicalin could alleviate ALD by raising the expression of miR-205. Additionally, miR-205 repressed NF-κB signaling pathway activation by binding to importinα5 to relieve ALD. Baicalin inhibited importinα5-mediated NF-κB signaling pathway to protect the liver against alcohol-induced injury, inflammation, oxidative stress and hepatocyte apoptosis. Taken conjointly, baicalin confers hepatoprotective effect against ALD through miR-205-mediated importinα5 inhibition via the NF-κB signaling pathway, highlighting a promising therapeutic target for ALD treatment with the help of traditional Chinese medicine.

Epigenetic modifications of tumor necrosis factor-alpha in joint cartilage tissue from osteoarthritis patients - CONSORT.

Background:Osteoarthritis (OA) remains one of the most common osteopathy for centuries, which can be attributed to multiple risk factors including mechanical and biochemical ones. More and more studies verified that inflammatory cytokines play important roles in the progression of OA, such as tumor necrosis factor-alpha (TNF-α). In this study, we aimed to investigate the relationship between epigenetic manifestations of TNF-? and the pathogenesis of OA.Methods:Totally, 37 OA patients’ cartilage was collected through the knee joint and 13 samples of articular cartilage as healthy control was collected through traumatic amputation. Real-time PCR, Western blot and ELISA analysis were performed to observe the expression of target genes and proteins in collected samples.Results:Compared with the healthy control group, TNF-? was over-expressing in cartilage which was collected from OA patients. DNA hypomethylation, histone hyperacetylation and histone methylation were observed in the TNF-? promoter in OA compared with normal patients, and we also studied series of enzymes associated with epigenetics. The results showed that by increasing DNA methylation and decreasing histone acetylation in the TNF-? promoter, and TNF-? over-expression in OA cartilage was suppressed, histone methylation has no significant correlation with OA.Conclusion:In conclusion, the changes of epigenetic status regulate TNF-α expression in the cells, which are pivotal to the OA disease process. These results may give us a better understanding of OA and may provide new therapeutic options.

Beneficial Effects of Betaine: A Comprehensive Review.

Simple SummaryA large number of studies report that medicinal herbs and many food ingredients protect against the development of liver disease because they possess antioxidant, anti-inflammatory, or anti-necrotic activities. This review focuses on the biological and beneficial effects of dietary betaine (trimethylglycine), a naturally occurring and crucial methyl donor, that restores methionine homeostasis in cells. We describe recent studies on betaine’s mechanism(s) of action as a therapeutic agent for improving indices of alcohol-induced and metabolic- associated liver disease. Due to its low cost, high tolerability, and efficacy, we suggest betaine as a promising therapeutic for clinical use to treat these aforementioned diseases as well as other liver-/non-liver-related diseases and conditions.Medicinal herbs and many food ingredients possess favorable biological properties that contribute to their therapeutic activities. One such natural product is betaine, a stable, nontoxic natural substance that is present in animals, plants, and microorganisms. Betaine is also endogenously synthesized through the metabolism of choline or exogenously consumed through dietary intake. Betaine mainly functions as (i) an osmolyte and (ii) a methyl-group donor. This review describes the major physiological effects of betaine in whole-body health and its ability to protect against both liver- as well as non-liver-related diseases and conditions. Betaine’s role in preventing/attenuating both alcohol-induced and metabolic-associated liver diseases has been well studied and is extensively reviewed here. Several studies show that betaine protects against the development of alcohol-induced hepatic steatosis, apoptosis, and accumulation of damaged proteins. Additionally, it can significantly prevent/attenuate progressive liver injury by preserving gut integrity and adipose function. The protective effects are primarily associated with the regulation of methionine metabolism through removing homocysteine and maintaining cellular SAM:SAH ratios. Similarly, betaine prevents metabolic-associated fatty liver disease and its progression. In addition, betaine has a neuroprotective role, preserves myocardial function, and prevents pancreatic steatosis. Betaine also attenuates oxidant stress, endoplasmic reticulum stress, inflammation, and cancer development. To conclude, betaine exerts significant therapeutic and biological effects that are potentially beneficial for alleviating a diverse number of human diseases and conditions.

MANF protects pancreatic acinar cells against alcohol-induced endoplasmic reticulum stress and cellular injury.

Heavy alcohol drinking is associated with pancreatitis. Pancreatitis is initiated by the damage to the pancreatic acinar cells. The endoplasmic reticulum (ER) stress has been shown to play an important role in alcohol-induced pancreatic damage. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an ER stress-inducible protein. The aim of the study was to determine whether MANF can ameliorate alcohol-induced ER stress and cellular damages to pancreatic acinar cells. Alcohol-induced damage to mouse pancreatic 266-6 acinar cells was determined by MTT and flow cytometry. MANF expression was downregulated by MANF siRNA using the Neon Transfection System. The overexpression of MANF was performed by the infection with the adenoviral vector carrying mouse MANF gene. The expression of ER stress markers was determined by immunoblotting and immunofluorescence. Alcohol caused ER stress, oxidative stress and induced apoptosis of 266-6 acinar cells. Recombinant human MANF alleviated alcohol-induced ER stress and cell death by inhibiting IRE1-caspase 12-caspase 3 apoptotic pathway. Overexpression of mouse MANF also protected cells against alcohol-induced apoptosis. In contrast, inhibiting MANF by siRNA exacerbated alcohol-induced cellular damage. MANF was protective against alcohol-induced ER stress and cellular injury in pancreatic acinar cells. The findings suggest a potential therapeutic value of MANF for alcoholic pancreatitis.

Red yeast rice prevents chronic alcohol-induced liver disease by attenuating oxidative stress and inflammatory response in mice.

Alcoholic liver disease (ALD) is characterized by dyslipidemia, hepatic steatosis, steatohepatitis, edema, necrosis, etc. Studies have reported that some dietary nutrition factors have beneficial effects in improving ALD. Red yeast rice (RYR), a traditional herbal supplement, has been confirmed to lower cholesterol mainly due to its component monacolin K. However, the effect of RYR on ALD has not been investigated. In this study, mice were supplemented with a daily oral gavage of 4g/kg 50% ethanol for 8weeks to induce a chronic ALD. RYR (150mgkg-1 day-1 ) was supplied to ALD mice in treatment group. The results showed that RYR supplementation significantly attenuated hyperlipidemia, elevated circulating inflammatory cytokines, hepatic structural damage, and oxidative stress in mice supplemented with alcohol with no effects on body weight. Moreover, RYR significantly suppressed alcohol-induced hepatic NF-κB activation and apoptosis. Our results suggest that RYR is capable of preventing ALD mainly by attenuating hepatic oxidative stress and inflammatory response. PRACTICAL APPLICATIONS: RYR was known for cholesterol-lowering effect through its main component monacolin K. The current study revealed that RYR was capable of ameliorating ALD, which is characterized by profound dyslipidemia, hepatic steatosis, steatohepatitis, edema, etc. Our results indicated that the protective effect of RYR on ALD is largely achieved by regulating lipid metabolism, and closely related to the anti-inflammatory and antioxidant effects of RYR. This study provides research foundation for the development of RYR-related food or pharmaceutical products, especially targeting for ALD.

Mulberry leaves extract ameliorates alcohol-induced liver damages through reduction of acetaldehyde toxicity and inhibition of apoptosis caused by oxidative stress signals.

Mulberry leaves (Morus alba L.), which are traditional Chinese herbs, exert several biological functions, such as antioxidant, anti-inflammation, antidiabetic, and antitumor. Alcohol intake increases inflammation and oxidative stress, and this increase causes liver injury and leads to liver steatosis, cirrhosis, and hepatocellular carcinoma, which are major health problems worldwide. Previous report indicated that mulberry leaf extract (MLE) exited hepatoprotection effects against chronic alcohol-induced liver damages. In this present study, we investigated the effects of MLE on acute alcohol and liver injury induced by its metabolized compound called acetaldehyde (ACE) by using in vivo and in vitro models. Administration of MLE reversed acute alcohol-induced liver damages, increased acetaldehyde (ACE) level, and decreased aldehyde dehydrogenase activity in a dose-dependent manner. Acute alcohol exposure-induced leukocyte infiltration and pro-inflammation factors, including cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), were blocked by MLE in proportion to MLE concentration. MLE prevented alcohol-induced liver apoptosis via enhanced caveolin-1 expression and attenuated EGFR/STAT3/iNOS pathway using immunohistochemical analysis. ACE induced proteins, such as iNOS, COX-2, TNF-α, and IL-6, and inhibited superoxide dismutase expression, whereas co-treated with MLE reversed these proteins expression. MLE also recovered alcohol-induced apoptosis in cultured Hep G2 cells. Overall, our findings indicated that MLE ameliorated acute alcohol-induced liver damages by reducing ACE toxicity and inhibiting apoptosis caused by oxidative stress signals. Our results implied that MLE might be a potential agent for treating alcohol liver disease.

Taxifolin, a novel food, attenuates acute alcohol-induced liver injury in mice through regulating the NF-κB-mediated inflammation and PI3K/Akt signalling pathways

Context Taxifolin (TAX) has effective anti-inflammatory, antioxidant and hepatoprotective activities, but its potential mechanism has not been revealed. Objective To evaluate the potential protective effect of TAX on acute alcohol-induced liver injury in mice. Materials and methods Alcoholic liver injury model was established by oral alcohol in mice, and randomly distributed in five groups (n = 10): Normal group (oral saline only); Alcohol group (concentration of fermented alcohol: 56%, 6 mL/kg); TAX groups, mice were orally administered with alcohol, and then TAX with doses of 20, 40, 80 mg/kg, respectively. Oral administration was conducted for 6 weeks. Results TAX treatment illustrated that the level of alanine aminotransferase (ALT) was reduced to 65.90 ± 2.26 U/L and aspartate aminotransferase (AST) to 33.28 ± 5.62 U/L compared with alcohol group (ALT 124.51 ± 4.40 U/L, AST 61.70 ± 4.09 U/L), while superoxide dismutase (SOD) was increased to 49.81 ± 2.39 U/mg and glutathione (GSH) to 8.16 ± 0.44 μmol/g, but MDA was reversed to 2.53 ± 0.24 nmol/mg. Histopathological examination showed TAX treatment alleviated alcohol-induced hepatocyte necrosis and inflammatory infiltration. Meanwhile, Western blot and rt-PCR indicated TAX reduced IL-6 to 2.49 ± 0.25 pg/mL and TNF-α to 1.79 ± 0.20 pg/mL, and inhibiting NF-κB activation in liver. Moreover, TAX reversed alcohol-induced apoptosis by regulating the expression of PI3K/Akt and its downstream apoptotic factors. Conclusions The research provides novel evidence of the hepatoprotective effect of TAX on alcohol-induced liver injury, while also providing the possibility for future treatment of alcoholic liver disease.

Elevated Fructose and Uric Acid Through Aldose Reductase Contribute to Experimental and Human Alcoholic Liver Disease.

Alcohol-associated liver disease (ALD) is a common chronic liver disease worldwide with high morbidity and mortality, and no Food and Drug Administration-approved therapies. Fructose (dietary or endogenous), its metabolite uric acid, and aldose reductase (AR, the only endogenous enzyme that produces fructose) are strongly associated with the development of nonalcoholic fatty liver disease. However, the role of AR or its metabolites in ALD remains understudied and was examined using human specimens, cultured cells, and mouse model systems. We demonstrated in liver specimens from patients with alcoholic hepatitis, the AR up-regulation and elevated AR metabolites (sorbitol, fructose, and uric acid), which correlated significantly with (1) increased lipid peroxidation byproducts and endoplasmic reticulum (ER) stress, (2) decreased protective ER chaperones, and (3) greater cell death and liver injury. Furthermore, we established a causal role for AR in ALD by showing that the genetic deficiency of AR (knockout mice) prevented alcohol-induced increase in harmful AR metabolites, toxic aldehydes, steatosis, ER stress, apoptosis, and liver injury. Finally, we demonstrated the therapeutic potential of pharmacological AR inhibition against alcohol-induced hepatic injury in experimental ALD. Our data demonstrate that hepatic AR up-regulation, and consequent elevation in fructose, sorbitol and/or uric acid, are important factors contributing to alcohol-induced steatosis, ER stress, apoptosis, and liver injury in both experimental and human ALD. Our study provides a strong rationale to evaluate AR as a potential therapeutic target and to test AR inhibitors to ameliorate alcohol-induced liver injury.

Modeling alcohol-induced neurotoxicity using human induced pluripotent stem cell-derived three-dimensional cerebral organoids

Maternal alcohol exposure during pregnancy can substantially impact the development of the fetus, causing a range of symptoms, known as fetal alcohol spectrum disorders (FASDs), such as cognitive dysfunction and psychiatric disorders, with the pathophysiology and mechanisms largely unknown. Recently developed human cerebral organoids from induced pluripotent stem cells are similar to fetal brains in the aspects of development and structure. These models allow more relevant in vitro systems to be developed for studying FASDs than animal models. Modeling binge drinking using human cerebral organoids, we sought to quantify the downstream toxic effects of alcohol (ethanol) on neural pathology phenotypes and signaling pathways within the organoids. The results revealed that alcohol exposure resulted in unhealthy organoids at cellular, subcellular, bioenergetic metabolism, and gene expression levels. Alcohol induced apoptosis on organoids. The apoptotic effects of alcohol on the organoids depended on the alcohol concentration and varied between cell types. Specifically, neurons were more vulnerable to alcohol-induced apoptosis than astrocytes. The alcohol-treated organoids exhibit ultrastructural changes such as disruption of mitochondria cristae, decreased intensity of mitochondrial matrix, and disorganized cytoskeleton. Alcohol exposure also resulted in mitochondrial dysfunction and metabolic stress in the organoids as evidenced by (1) decreased mitochondrial oxygen consumption rates being linked to basal respiration, ATP production, proton leak, maximal respiration and spare respiratory capacity, and (2) increase of non-mitochondrial respiration in alcohol-treated organoids compared with control groups. Furthermore, we found that alcohol treatment affected the expression of 199 genes out of 17,195 genes analyzed. Bioinformatic analyses showed the association of these dysregulated genes with 37 pathways related to clinically relevant pathologies such as psychiatric disorders, behavior, nervous system development and function, organismal injury and abnormalities, and cellular development. Notably, 187 of these genes are critically involved in neurodevelopment, and/or implicated in nervous system physiology and neurodegeneration. Furthermore, the identified genes are key regulators of multiple pathways linked in networks. This study extends for the first time animal models of binge drinking-related FASDs to a human model, allowing in-depth analyses of neurotoxicity at tissue, cellular, subcellular, metabolism, and gene levels. Hereby, we provide novel insights into alcohol-induced pathologic phenotypes, cell type-specific vulnerability, and affected signaling pathways and molecular networks, that can contribute to a better understanding of the developmental neurotoxic effects of binge drinking during pregnancy.

ABHD4-dependent developmental anoikis safeguards the embryonic brain

A specialized neurogenic niche along the ventricles accumulates millions of progenitor cells in the developing brain. After mitosis, fate-committed daughter cells delaminate from this germinative zone. Considering the high number of cell divisions and delaminations taking place during embryonic development, brain malformations caused by ectopic proliferation of misplaced progenitor cells are relatively rare. Here, we report that a process we term developmental anoikis distinguishes the pathological detachment of progenitor cells from the normal delamination of daughter neuroblasts in the developing mouse neocortex. We identify the endocannabinoid-metabolizing enzyme abhydrolase domain containing 4 (ABHD4) as an essential mediator for the elimination of pathologically detached cells. Consequently, rapid ABHD4 downregulation is necessary for delaminated daughter neuroblasts to escape from anoikis. Moreover, ABHD4 is required for fetal alcohol-induced apoptosis, but not for the well-established form of developmentally controlled programmed cell death. These results suggest that ABHD4-mediated developmental anoikis specifically protects the embryonic brain from the consequences of sporadic delamination errors and teratogenic insults.