Alcohol and mitochondria: a dysfunctional relationship

Crocin and gallic acid attenuate ethanol-induced mitochondrial dysfunction via suppression of ROS formation and inhibition of mitochondrial swelling in pancreatic mitochondria

Chronic/heavy exposure with ethanol is associated with risk of type 2 diabetes, due to β-cells dysfunction. It has been reported that ethanol can induce oxidative stress directly or indirectly by involvement of mitochondria. We aimed to explore the protective effects of the crocin/gallic acid/L-alliin as natural antioxidants separately on ethanol-induced mitochondrial damage. Intact mitochondria are isolated from pancreas by differential centrifugation and directly treated with toxic concentrations of ethanol (8% v/v) in the presence of different concentrations crocin/gallic acid/L-alliin (100, 500, and 1000 µM). Biomarkers of mitochondrial toxicity including the succinate dehydrogenases (SDH) activity, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), mitochondrial swelling, lipid peroxidation, and glutathione content were assessed. The results showed that 8% v/v ethanol-treated rat pancreas-isolated mitochondria for 1 h resulted in a significant decrease of SDH activity to 81.34 ± 3.48%, a significant increase of ROS formation, MDA content, mitochondrial swelling, and collapse of MMP. Among three tested natural compounds, treatment with crocin and gallic acid significantly reversed the changes of the above indicators and resulted in the increase of SDH activity, improvement of MMP collapse and mitochondrial swelling, and reduction of ROS formation and oxidative stress in pancreas-isolated mitochondria. This study demonstrated that crocin and gallic acid had direct protective effects on the mitochondrial damages induced by ethanol in pancreas-isolated mitochondria, and these natural compounds could be developed as mitochondrial protective agents in the prevention of pancreatic β-cells and diabetogenic effect of ethanol.

Alcohol Exposure May Increase Prenatal Choline Needs Through Redirection of Choline into Lipid Synthesis Rather than Methyl Donation

Background: Prenatal alcohol exposure (PAE) can reduce fetal growth and cause neurodevelopmental disability. Prenatal choline supplements attenuate PAE-induced behavioral and growth deficits; however, the underlying mechanisms are unknown. Alcohol alters nutrient metabolism and potentially increases nutrient needs. Here, we investigate how alcohol affects choline metabolism in the maternal-fetal dyad and the role of supplemental choline. Methods: Pregnant C57BL/6J mice were assigned to one of four groups: alcohol-exposed (3 g/kg alcohol/day) or control +/- 100 mg/kg choline daily from embryonic day (E)8.5-17.5. We performed an exploratory hypothesis-generating analysis of targeted metabolomics on choline-related metabolites in the maternal liver, plasma, placenta, and fetal brain at E17.5 and Spearman correlation analyses to determine their association with gestational and fetal growth outcomes. Results: Although choline levels were largely unaffected by alcohol or choline, alcohol increased many lipid products in the CDP-choline pathway; this was not normalized by choline. Alcohol increased placental CDP-ethanolamine and reduced the maternal hepatic SAM/SAH ratio as well as dimethylglycine and the serine/glycine ratio across the dyad, suggesting a functional insufficiency in methyl donor pools. These outcomes were rescued by supplemental choline. Correlation analyses among choline metabolites and fetal growth outcomes suggest that maternal plasma methionine, serine, and the serine/glycine ratio may be predictive of maternal-fetal choline status. Conclusions: The increased hepatic lipid synthesis that characterizes chronic alcohol exposure may draw choline into phospholipid biosynthesis at the expense of its use as a methyl donor. We propose that PAE increases choline needs, and that its supplementation is necessary to fulfill these competing demands for lipid and methyl use.

Pemafibrate modulates peroxisome proliferator-activated receptor alpha and prevents alcohol-associated liver disease in rats

BACKGROUND AND AIMS

Alcohol-associated liver disease (ALD) with steatosis or steatohepatitis that could progress to liver cirrhosis is a common problem in chronic alcohol consumption. Pemafibrate is a novel, highly specific peroxisome proliferator-activated receptor-α (PPARα) modulator, which regulates the expression of the target genes related to lipid and glucose metabolism. Here, we evaluated the effect of pemafibrate to prevent ALD and steatosis in rats.

METHODS

The animals were treated with liquid diet containing ethanol (36% of total calories) or an isocaloric carbohydrate diet for 4 weeks. Subsequently, both groups were fed with either 0.5% aqueous methylcellulose solution (MC) or MC containing 0.3 mg/kg body weight of pemafibrate orally twice a day along with the liquid diet for another 4 weeks. A set of animals were sacrificed at the 4th week before the start of pemafibrate treatment and the remaining animals at the end of 8 weeks. Blood and liver samples were collected for biochemical and histopathological evaluations.

RESULTS

Treatment with pemafibrate prevented inflammation and steatosis in the hepatic tissue. Furthermore, pemafibrate administration markedly increased hepatic NAD and NADH levels, reduced both serum and hepatic triglyceride levels, and upregulated the expression of molecules involved in lipid metabolism.

CONCLUSIONS

The results of the present study demonstrated that pemafibrate modulates target genes related to hepatic lipid metabolism and prevents deposition of fat globules in the liver during chronic alcohol feeding in rats. Therefore, pemafibrate could be used as a potent therapeutic agent to prevent steatosis and related adverse events in ALD.

Ethanol Inhalation for Respiratory Infections due to Enveloped Viruses

Ethanol has demonstrated high efficacy in inactivating enveloped viruses in vitro and in vivo (in animal and human studies). The inhalation route has been a significant method of drug administration for respiratory disorders since ancient times. Infections with enveloped viruses cause many respiratory diseases. This concise review explores the general structural characteristics of enveloped viruses and examines the potential role of inhaled ethanol as a low-cost therapy for respiratory diseases. Current literature data suggest that ethanol inhalation could be beneficial in treating respiratory infections caused by enveloped viruses. However, there is a clear gap in well-designed clinical trials assessing the safety and efficacy of ethanol inhalation in treating respiratory infections from enveloped viruses. This low-cost therapy could become an important therapeutic option, especially for large numbers of patients simultaneously infected, as was the case during the coronavirus disease 2019 (COVID-19) pandemic. In addition, inhaled ethanol could be a successful approach for vulnerable patients such as patients with cancer because it is likely to have no or minimal effects on already established life-saving treatments. Further investigation by national and international institutions is urgently needed to validate these findings and refine treatment protocols.

Mitochondrial Dysfunction and Atherosclerosis: The Problem and the Search for Its Solution

Background/Objectives: This review has been prepared to promote interest in the interdisciplinary study of mitochondrial dysfunction (MD) and atherosclerosis. This review aims to describe the state of this problem and indicate the direction for further implementation of this knowledge in clinical medicine. Methods: Extensive research of the literature was implemented to elucidate the role of the molecular mechanisms of MD in the pathogenesis of atherosclerosis. Results: A view on the pathogenesis of atherosclerosis through the prism of knowledge about MD is presented. MD is the cause and primary mechanism of the onset and progression of atherosclerosis. It is proposed that this problem be considered in the context of a continuum. Conclusions: MD and atherosclerosis are united by common molecular mechanisms of pathogenesis. Knowledge of MD should be used to argue for a healthy lifestyle as the primary way to prevent atherosclerosis. The development of new approaches to diagnosing and treating MD in atherosclerosis is an urgent task and challenge for modern science.

Reactive Oxygen Species as a Common Pathological Link Between Alcohol Use Disorder and Alzheimer's Disease with Therapeutic Implications

Chronic alcohol consumption leads to excessive production of reactive oxygen species (ROS), driving oxidative stress that contributes to both alcohol use disorder (AUD) and Alzheimer's disease (AD). This review explores how ROS-mediated mitochondrial dysfunction and neuroinflammation serve as shared pathological mechanisms linking these conditions. We highlight the role of alcohol-induced oxidative damage in exacerbating neurodegeneration and compare ROS-related pathways in AUD and AD. Finally, we discuss emerging therapeutic strategies, including mitochondrial antioxidants and inflammasome inhibitors, that target oxidative stress to mitigate neurodegeneration. Understanding these overlapping mechanisms may provide new insights for preventing and treating ROS-driven neurodegenerative disorders.

Expression of GDAP1 Gene Correlates With Alcohol Deprivation Effect

Alcohol addiction is a widespread disease, and the exact causes and consequences are still not fully determined. Neurotransmitters and neuronal circuits are not only the target structure of alcohol and responsible for its direct effects but also play a central role in the development of addiction. A gene that has been linked to alcohol use disorder in recent studies is the ganglioside-induced differentiation-associated protein 1 (GDAP1) gene. The present study focuses on the hippocampus, a brain region particularly vulnerable to alcohol and rich in Gdap1 gene expression. Using an established drinking model, alcohol drinking behavior was induced in adult male Long Evans rats. After 6 weeks of voluntary alcohol intake, followed by 2 weeks of deprivation, the animals were divided into two groups based on the alcohol deprivation effect (ADE). Gdap1 gene expression was measured with real-time PCR in the hippocampus. Results reveal significantly decreased mRNA expression in the high ADE group compared to the low ADE group. This decrease was specifically detected within the cornu ammonis 3 (CA3) region. Gdap1 expression in this region also negatively correlated with ADE in all animals. Taken together, results indicate that Gdap1 might not only be associated with alcohol consumption but might even play a role in alcohol dependence.

Deciphering the Role of Oxidative Stress in Male Infertility: Insights from Reactive Oxygen Species to Antioxidant Therapeutics

Male infertility represents a major health concern, accounting for approximately 50% of all infertility cases in couples. This condition arises from multiple etiologies, with oxidative stress gaining increasing attention in recent studies. During the final stages of sperm maturation, the majority of the cytoplasm is discarded, leaving sperm with a diminished antioxidant defense system, which makes them highly susceptible to the detrimental effects of reactive oxygen species (ROS). ROS can be generated from both intrinsic and extrinsic sources. Intrinsically, ROS are primarily produced by mitochondrial activity, while extrinsic factors include alcohol consumption, smoking, circadian rhythm disruption, gut microbiota imbalance, and leukocyte infiltration. Excessive ROS production leads to DNA damage, apoptosis, and epigenetic modifications in sperm, ultimately impairing sperm motility and contributing to infertility. This review provides a comprehensive examination of ROS sources and examines the mechanisms by which ROS induce sperm damage. Furthermore, it explores the therapeutic potential of antioxidants in mitigating oxidative stress and improving sperm quality.

TNF/TNFR1 Signaling Mediates DEHP-Induced Hepatocyte Pyroptosis via the GSDMD-mtROS Axis

Di(2-ethylhexyl) phthalate (DEHP), which is widely used in agricultural plastics, accumulates in humans and animals through the food chain over time, resulting in liver toxicity. Recent studies have reported that pyroptosis and mitochondrial damage are closely related to a variety of liver diseases, but the specific mechanism is still unclear. To address this issue, in vitro and in vivo hepatotoxicity models were established. The results demonstrated that exposure to DEHP caused a buildup of MEHP in livers, altered liver metabolite composition, and caused pyroptosis-like changes in hepatocytes. After DEHP treatment, REDOX homeostasis was unbalanced, and mitochondrial reactive oxygen species (mtROS) were overproduced. MEHP exposure activates pyroptosis mediated by TNF/TNFR1 signaling and upregulates the perforating protein GSDMD-N to destroy the mitochondrial membrane of hepatocytes. Above all, this study elucidates the potential involvement of TNF/TNFR1 signaling-mediated pyroptosis in mitochondrial damage and confirms that the regulation of pyroptosis is helpful in maintaining normal mitochondrial function.

Oxidative stress in a cellular model of alcohol-related liver disease: protection using curcumin nanoformulations

Alcohol-related liver disease (ARLD) is a global health issue causing significant morbidity and mortality, due to lack of suitable therapeutic options. ARLD induces a spectrum of biochemical and cellular alterations, including chronic oxidative stress, mitochondrial dysfunction, and cell death, resulting in hepatic injury. Natural antioxidant compounds such as curcumin have generated interest in ARLD due to their ability to scavenge reactive oxygen species (ROS), however, therapy using these compounds is limited due to poor bioavailability and stability. Therefore, the aim of this study was to assess the antioxidant potential of free antioxidants and curcumin entrapped formulations against oxidative damage in an ARLD cell model. HepG2 (VL-17A) cells were treated with varying concentrations of alcohol (from 200 to 350 mM) and parameters of oxidative stress and mitochondrial function were assessed over 72 h. Data indicated 350 mM of ethanol led to a significant decrease in cell viability at 72 h, and a significant increase in ROS at 30 min. A substantial number of cells were in late apoptosis at 72 h, and a reduction in the mitochondrial membrane potential was also found. Pre-treatment with curcumin nanoformulations increased viability, as well as, reducing ROS at 2 h, 48 h and 72 h. In summary, antioxidants and entrapped nanoformulations of curcumin were able to ameliorate reduced cell viability and increased ROS caused by ethanol treatment. This demonstrates their potential at mitigating oxidative damage and warrants further investigation to evaluate their efficacy for ARLD therapy.

Effects of periconceptional ethanol on mitochondrial content and oxidative stress in maternal liver and placentas from male and female fetuses in rats

Alcohol exposure during pregnancy disrupts fetal development and programs lifelong disease. We have shown, in rats, that alcohol exposure during the periconceptional period (PC:EtOH), causes placental dysfunction and cardiometabolic disease in offspring. The process of metabolising alcohol can cause oxidative stress and damage mitochondrial DNA (mtDNA). It is unknown whether alcohol metabolism in a rat model of PC:EtOH impacts oxidative stress markers and mitochondrial content in maternal and placental tissues. We aimed to determine whether PC:EtOH induced oxidative stress and reduced mtDNA in maternal liver and the placental labyrinth and junctional zone. Sprague-Dawley rats were given an ethanol liquid (12.5% v/v) or control (0%) diet for one oestrous cycle before mating to embryonic day (E) 4. Maternal livers were collected at E5 and E20. Placentas were collected at E20 and separated into the junctional zone and labyrinth zone. PC:EtOH reduced Cyp2e1 mRNA levels and mtDNA in the E5 liver with lower mtDNA persisting to E20, at which time mitochondrial proteins were also decreased. PC:EtOH also reduced mitochondrial content in the E20 junctional zone, although mitochondrial protein levels were unaffected. Superoxide dismutase activity was increased in the placental junctional zone and there was no evidence of oxidative stress. The present study demonstrates that alcohol exposure around conception, reduces mitochondrial content within the maternal liver and the junctional zone of the placenta towards the end of pregnancy. These prolonged deficits may have disrupted metabolic processes required for a healthy pregnancy. The study further supports avoiding alcohol when planning a pregnancy. KEY POINTS: Even when alcohol is consumed only around conception (PC:EtOH), it can have profound impacts on the developing baby. Here, we use our established rat model to investigate if PC:EtOH causes oxidative stress and reduces mitochondrial content in the maternal liver immediately after exposure on embryonic day (E) 5. We also investigate these parameters at the end of pregnancy (E20) in maternal liver and the placenta. PC:EtOH reduced mitochondrial DNA content in the maternal liver by 77% at E5 and by 40% at E20. At E20, expression of proteins that form the electron transport chain were also reduced. The placenta had a more subtle reduction in mitochondrial DNA content, but protein levels of mitochondrial complexes were unchanged. There was no evidence of oxidative stress in the maternal liver or placenta in response to PC:EtOH. The lack of oxidative stress in the placenta may be a result of compensatory increases in antioxidants.

Chronic alcohol consumption exacerbates ischemia-associated skeletal muscle mitochondrial dysfunction in a murine model of peripheral artery disease

PURPOSE

Peripheral artery disease (PAD) causes ischemic mitochondriopathy-associated muscle damage, amplifying patient disability and mortality. Although alcohol and a high-fat diet enhance PAD predisposition and severity, their impact on PAD myopathy is unclear. Using our murine model of PAD, we investigated the combined effect of chronic alcohol and fat consumption on intramuscular oxidative stress and mitochondrial content, function, and quality control. The potential relationship between intramuscular aldehyde dehydrogenase 2 (ALDH2) content, oxidative stress and mitochondriopathy was also explored.

METHODS

Twenty-four male, 24 female, 8-month-old C57BL/6 J mice received high-fat-sucrose (HFS) or low-fat-sucrose (LFS) diets for 16-weeks, followed by either 20 % ethanol (EtOH) supplemented in the drinking water or continued water access for another 12-weeks (n = 12 mice/4 groups). The left femoral artery was ligated to induce hindlimb ischemia (HLI), and mice 4-weeks post-ligation were euthanized.

RESULTS

Chronic HLI was associated with an ischemic muscle mitochondriopathy, which was exacerbated by concurrent HFS and EtOH feeding. Intramuscular ALDH2 was also reduced in mice consuming HFS + EtOH, particularly in the ischemic limb, but increased in their LFS + EtOH-consuming counterparts. Moreover, reduced ALDH2 was strongly correlated with markers of oxidative stress and mitochondrial dysfunction.

CONCLUSIONS

ALDH2 could be a promising therapeutic target to optimize intramuscular mitochondrial function in PAD patients, particularly those who habitually consume a diet high in fat and alcohol.

Visium spatial transcriptomics and proteomics identifies novel hepatic cell populations and transcriptomic signatures of alcohol-associated hepatitis

BACKGROUND

Alcohol-associated hepatitis (AH) is the clinical manifestation of alcohol-associated liver disease (ALD). AH is a complex disease encompassing the dysregulation of many cells and cell subpopulations. This study used a hepatic spatial transcriptomic and proteomic approach (10X Genomics Visium) to identify hepatic cell populations and their associated transcriptomic and proteomic alterations in human AH.

METHODS

Formalin-fixed paraffin-embedded liver tissue from AH patients (n = 2) and non-ALD controls (donors) (n = 2) were used for Visium spatial transcriptomic and proteomic analysis.

RESULTS

AH cell clusters and cell markers were drastically different in regard to tissue pattern and number of cell types compared to non-ALD controls. Cholangiocytes, endothelial cells, macrophages, and stellate cells were more profuse in AH relative to non-ALD controls. Transcriptionally, proliferating cell nuclear antigen-positive (PCNA+) hepatocytes in AH more closely resembled cholangiocytes suggesting they were non-functional hepatocytes derived from cholangiocytes. Furthermore, mitochondria protein-coding genes were reduced in AH versus non-ALD control hepatocytes, suggesting reduced functionality and loss of regenerative mechanisms. Macrophages in AH exhibited elevated gene expression involved in exosomes as compared to non-ALD controls. The most upregulated macrophage genes observed in AH were those involved in exosome trafficking. Gene and protein signatures of disease-associated hepatocytes (ANXA2+/CXCL1+/CEACAM8+) were elevated in AH and could visually identify a pre-malignant lesion.

CONCLUSIONS

This study identified global cell type alterations in AH and distinct transcriptomic changes between AH and non-ALD controls. These findings characterize cellular plasticity and profuse transcriptomic and proteomic changes that are apparent in AH and contribute to the identification of novel therapeutics.

Hepatoprotective potentials of Usnea longissima Ach. and Xanthoparmelia somloensis (Gyelnik) Hale extracts in ethanol-induced liver injury

In our study, the antioxidant and anti-inflammatory effects of different lichen applications were investigated in rats using an experimental ethanol toxicity model. 48 rats were used in the study and they were divided into 6 groups with 8 rats in each group. These groups were: control, ethanol (2 g/kg), ethanol + Usnea longissima Ach. (200 mg/kg), ethanol + Usnea longissima Ach. (400 mg/kg), ethanol + Xanthoparmelia somloensis (Gyelnik) Hale (100 mg/kg) and ethanol + Xanthoparmelia somloensis (Gyelnik) Hale (200 mg/kg). The experimental work continued for 21 days. Lichen extracts and ethanol were administered by gavage to rats divided into groups. According to the experimental protocol, the experimental animals were sacrificed and their liver tissues were isolated. Biochemical parameters in serum, histological examinations, oxidative stress and inflammation parameters both at biochemical and molecular level in liver tissues were performed. Oxidative stress and inflammatory response were increased in the liver tissue of rats treated with ethanol for 21 days, and liver functions were impaired. It was found that U. longissima and X. somloensis extracts showed good antioxidant activity and conferred protective effects against ethanol-induced oxidative stress and inflammation. This could be attributed to the presence of secondary metabolites in the extract, which act as natural antioxidants and could be responsible for increasing the defence mechanisms against free radical production induced by ethanol administration.

Sexual Dimorphism of Ethanol-Induced Mitochondrial Dynamics in Purkinje Cells

The cerebellum, a key target of ethanol's toxic effects, is associated with ataxia following alcohol consumption. However, the impact of ethanol on Purkinje cell (PC) mitochondria remains unclear. To investigate how ethanol administration affects mitochondrial dynamics in cerebellar Purkinje cells, we employed a transgenic mouse model expressing mitochondria-targeted yellow fluorescent protein in Purkinje cells (PC-mito-eYFP). Both male and female PC-mito-eYFP mice received an intraperitoneal injection of ethanol or vehicle. One hour after ethanol administration, the animals were perfusion fixed or their cerebellum tissue or isolated mitochondria were collected. Cerebellum sections were analyzed using confocal microscopy to assess changes in mitochondrial length distribution. In vivo superoxide levels were measured using dihydroethidium (DHE), and mitochondrial NAD levels were determined by high-performance liquid chromatography (HPLC). Our findings revealed a sex-dependent response to ethanol administration in mitochondrial size distribution. While male Purkinje cell mitochondria exhibited no significant changes in size, female mitochondria became more fragmented after one hour of ethanol administration. This coincided with elevated phosphorylation of the fission protein Drp1 and increased superoxide production, as measured by DHE fluorescence intensity. Similarly, mitochondrial NAD levels were significantly reduced in female mice, but no changes were observed in males. Our results demonstrate that ethanol induced mitochondrial fragmentation through increased free radical levels, due to reduced NAD and increased p-Drp1, in PC cells of the female cerebellum.

Alcohol Consumption and Breast and Ovarian Cancer Development: Molecular Pathways and Mechanisms

Alcohol consumption has been consistently linked to an increased risk of several cancers, including breast and ovarian cancer. Despite substantial evidence supporting this association, the precise mechanisms underlying alcohol's contribution to cancer pathogenesis remain incompletely understood. This narrative review focuses on the key current literature on the biological pathways through which alcohol may influence the development of breast and ovarian cancer. Key mechanisms discussed include the modulation of estrogen levels, the generation of reactive oxygen species, the production of acetaldehyde, the promotion of chronic inflammation, and the induction of epigenetic changes. Alcohol's impact on estrogenic signaling, particularly in the regulation of estrogen and progesterone, is explored in the context of hormone-dependent cancers. Additionally, the role of alcohol-induced DNA damage, mutagenesis, and immune system modulation in tumor initiation and progression is examined. Overall, this review emphasizes the importance of alcohol as a modifiable risk factor for breast and ovarian cancer and highlights the need for further research to clarify its role in cancer biology.

Nobiletin protects against alcohol-induced mitochondrial dysfunction and liver injury by regulating the hepatic NRF1-TFAM signaling pathway

OBJECTIVES

Alcohol and its metabolites, such as acetaldehyde, induced hepatic mitochondrial dysfunction play a pathological role in the development of alcohol-related liver disease (ALD).

METHODS

In this study, we investigated the potential of nobiletin (NOB), a polymethoxylated flavone, to counter alcohol-induced mitochondrial dysfunction and liver injury.

RESULTS

Our findings demonstrate that NOB administration markedly attenuated alcohol-induced hepatic steatosis, endoplasmic reticulum stress, inflammation, and tissue damage in mice. NOB reversed hepatic mitochondrial dysfunction and oxidative stress in both alcohol-fed mice and acetaldehyde-treated hepatocytes. Mechanistically, NOB restored the reduction of hepatic mitochondrial transcription factor A (TFAM) at both mRNA and protein levels. Notably, the protective effects of NOB against acetaldehyde-induced mitochondrial dysfunction and cell death were abolished in hepatocytes lacking Tfam. Furthermore, NOB administration reinstated the levels of hepatocellular NRF1, a key transcriptional regulator of TFAM, which were decreased by alcohol and acetaldehyde exposure. Consistent with these findings, hepatocyte-specific overexpression of Nrf1 protected against alcohol-induced hepatic Tfam reduction, mitochondrial dysfunction, oxidative stress, and liver injury.

CONCLUSIONS

Our study elucidates the involvement of the NRF1-TFAM signaling pathway in the protective mechanism of NOB against chronic-plus-binge alcohol consumption-induced mitochondrial dysfunction and liver injury, suggesting NOB supplementation as a potential therapeutic strategy for ALD.

Emerging pharmacological targets for alcohol use disorder

Alcohol Use Disorder (AUD) remains a challenging condition with limited effective treatment options; however new technology in drug delivery and advancements in pharmacology have paved the way for discovery of novel therapeutic targets. This review explores emerging pharmacological targets that offer new options for the management of AUD, focusing on the potential of somatostatin (SST), vasoactive intestinal peptide (VIP), glucagon-like peptide-1 (GLP-1), nociceptin (NOP), and neuropeptide S (NPS). These targets have been selected based on recent advancements in preclinical and clinical research, which suggest their significant roles in modulating alcohol consumption and related behaviors. SST dampens cortical circuits, and targeting both the SST neurons and the SST peptide itself presents promise for treating AUD and various related comorbidities. VIP neurons are modulated by alcohol and targeting the VIP system presents an unexplored avenue for addressing alcohol exposure at various stages of development. GLP-1 interacts with the dopaminergic reward system and reduces alcohol intake. Nociceptin modulates mesolimbic circuitry and agonism and antagonism of nociceptin receptor offers a complex but promising approach to reducing alcohol consumption. NPS stands out for its anxiolytic-like effects, particularly relevant for the anxiety associated with AUD. This review aims to synthesize the current understanding of these targets, highlighting their potential in developing more effective and personalized AUD therapies, and underscores the importance of continued research in identifying and validating novel targets for treatment of AUD and comorbid conditions.

Alcohol Alters Skeletal Muscle Bioenergetic Function: A Scoping Review

Bioenergetic pathways uniquely support sarcomere function which, in turn, helps to maintain functional skeletal muscle (SKM) mass. Emerging evidence supports alcohol (EtOH)-induced bioenergetic impairments in SKM and muscle precursor cells. We performed a scoping review to synthesize existing evidence regarding the effects of EtOH on SKM bioenergetics. Eligible articles from six databases were identified, and titles, abstracts, and full texts for potentially relevant articles were screened against inclusion criteria. Through the search, we identified 555 unique articles, and 21 met inclusion criteria. Three studies investigated EtOH effects on the adenosine triphosphate (ATP)-phosphocreatine (PCr) system, twelve investigated EtOH effects on glycolytic metabolism, and seventeen investigated EtOH effects on mitochondrial metabolism. Despite increased ATP-PCr system reliance, EtOH led to an overall decrease in bioenergetic function through decreased expression and activity of glycolytic and mitochondrial pathway components. However, effects varied depending on the EtOH dose and duration, model system, and sample type. The results detail the EtOH-induced shifts in energy metabolism, which may adversely affect sarcomere function and contribute to myopathy. These findings should be used to develop targeted interventions that improve SKM bioenergetic function, and thus sarcomere function, in people with Alcohol Use Disorder (AUD). Key areas in need of further investigation are also identified.

Mitochondrial quality control in alcohol-associated liver disease

Excessive alcohol consumption is a leading cause of alcohol-associated liver disease (ALD), a significant global health concern with limited therapeutic options. Understanding the key factors contributing to ALD pathogenesis is crucial for identifying potential therapeutic targets. Central to ALD pathogenesis is the intricate interplay between alcohol metabolism and cellular processes, particularly involving mitochondria. Mitochondria are essential organelles in the liver, critical for energy production and metabolic functions. However, they are particularly vulnerable to alcohol-induced damage due to their involvement in alcohol metabolism. Alcohol disrupts mitochondrial function, impairing ATP production and triggering oxidative stress, which leads to cellular damage and inflammation. Mitochondrial quality control mechanisms, including biogenesis, dynamics, and mitophagy, are crucial for maintaining optimal mitochondrial function. Chronic alcohol consumption disrupts mitochondrial quality control checkpoints, leading to mitochondrial dysfunction that impairs fatty acid oxidation and contributes to hepatic steatosis in ALD. Moreover, alcohol promotes the accumulation of damaged mitochondria and the release of proinflammatory components, exacerbating liver damage and inflammation. Preserving mitochondrial health presents a promising therapeutic approach to mitigate ALD progression. In this review, we provide a comprehensive overview of the effects of alcohol on mitochondrial function and quality control mechanisms, highlighting their role in ALD pathogenesis. Understanding these mechanisms may pave the way for the development of novel therapeutic interventions for ALD.

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.

1,2-Dicinnamoyl-sn-glycero-3-phosphocholine Improves Insulin Sensitivity and Upregulates mtDNA-Encoded Genes in Insulin-Resistant 3T3-L1 Adipocytes: A Preliminary Study

BACKGROUND

Insulin resistance is a condition characterized by a reduced biological response to insulin. It is one of the most common metabolic diseases in modern civilization. Numerous natural substances have a positive effect on metabolism and energy homeostasis including restoring the proper sensitivity to insulin. There may be several possible mechanisms of action. In the present study, we elucidated two natural compounds with an impact on insulin signaling in IR adipocytes involving mitochondria.

METHODS

Mature 3T3-L1 adipocytes with artificially induced insulin resistance by palmitic acid (16:0) were used for the study. Cinnamic acid and 1,2-dicinnamoyl-sn-glycero-3-phosphocholin (1,2-diCA-PC) were tested at three concentrations: 25 μM, 50 μM, and 125 μM. The number of mitochondria and the expression of genes encoded by mtDNA were elucidated in control and experimental cells.

RESULTS

Experimental cells treated with 1,2-diCA-PC displayed increased insulin-stimulated glucose uptake in a dose-dependent manner, accompanied by an increase in mtDNA copy number. Moreover, in experimental cells treated with 1,2-diCA-PC at a concentration of 125 μM, a significant increase in the expression level of all analyzed genes encoded by mtDNA compared to control cells was observed. Our study showed a relationship between improved cellular sensitivity to insulin by 1,2-diCA-PC and an increase in the number of mitochondria and expression levels of genes encoded by mtDNA.

CONCLUSIONS

To summarize, the results suggest the therapeutic potential of cinnamic acid derivative 1,2-diCA-PC to enhance the insulin sensitivity of adipocytes.

Inhibition of ethanol-induced eNAMPT secretion attenuates liver ferroptosis through BAT-Liver communication

BACKGROUND & AIMS

Extracellular nicotinamide phosphoribosyltransferase (eNAMPT) has long been recognized as an adipokine. However, the exact role of eNAMPT in alcoholic liver disease (ALD) and its relevance to brown adipose tissue (BAT) remain largely unknown. This study aimed to evaluate the impact of eNAMPT on liver function and the underlying mechanisms involved in BAT-Liver communication.

METHODS

Serum eNAMPT levels were detected in the serum of both ALD patients and mice. Chronic and binge ethanol feeding was used to induce alcoholic liver injury in mice. An eNAMPT antibody, a coculture model of brown adipocytes and hepatocytes, and BAT-specific Nampt knockdown mice were used to investigate the role of eNAMPT in ALD.

RESULTS

Serum eNAMPT levels are elevated in ALD patients and are significantly positively correlated with the liver injury index. In ALD mice, neutralizing eNAMPT reduced the elevated levels of circulating eNAMPT induced by ethanol and attenuated liver injury. In vitro experiments revealed that eNAMPT induced hepatocyte ferroptosis through the TLR4-dependent mitochondrial ROS-induced ferritinophagy pathway. Furthermore, ethanol stimulated eNAMPT secretion from brown adipocytes but not from other adipocytes. In the coculture model, ethanol-induced release of eNAMPT from brown adipocytes promoted hepatocyte ferroptosis. In BAT-specific Nampt-knockdown mice, ethanol-induced eNAMPT secretion was significantly reduced, and alcoholic liver injury were attenuated. These effects can be reversed by intraperitoneal injection of eNAMPT.

CONCLUSION

Inhibition of ethanol-induced eNAMPT secretion from BAT attenuates liver injury and ferroptosis. Our study reveals a previously uncharacterized critical role of eNAMPT-mediated BAT-Liver communication in ALD and highlights its potential as a therapeutic target.

Role of Neutrophils in the Development of Steatotic Liver Disease

This review explores the biological aspects of neutrophils, their contributions to the development of steatotic liver disease, and their potential as therapeutic targets for the disease. Although alcohol-associated and metabolic dysfunction-associated liver diseases originate from distinct etiological factors, the two diseases frequently share excessive lipid accumulation as a common contributor to their pathogenesis, thereby classifying them as types of steatotic liver disease. Dysregulated lipid deposition in the liver induces hepatic injury, triggering the activation of the innate immunity, partially through neutrophil recruitment. Traditionally recognized for their role in microbial clearance, neutrophils have recently garnered attention for their involvement in sterile inflammation, a pivotal component of steatotic liver disease pathogenesis. In conclusion, technological innovations, including single-cell RNA sequencing, have gradually disclosed the existence of various neutrophil subsets; however, how the distinct subsets of neutrophil population contribute differentially to the development of steatotic liver disease remains unclear.

The relationship of redox signaling with the risk for atherosclerosis

Oxidative balance plays a pivotal role in physiological homeostasis, and many diseases, particularly age-related conditions, are closely associated with oxidative imbalance. While the strategic role of oxidative regulation in various diseases is well-established, the specific involvement of oxidative stress in atherosclerosis remains elusive. Atherosclerosis is a chronic inflammatory disorder characterized by plaque formation within the arteries. Alterations in the oxidative status of vascular tissues are linked to the onset, progression, and outcome of atherosclerosis. This review examines the role of redox signaling in atherosclerosis, including its impact on risk factors such as dyslipidemia, hyperglycemia, inflammation, and unhealthy lifestyle, along with dysregulation, vascular homeostasis, immune system interaction, and therapeutic considerations. Understanding redox signal transduction and the regulation of redox signaling will offer valuable insights into the pathogenesis of atherosclerosis and guide the development of novel therapeutic strategies.

Mitochondrial dynamics, quality control, and mtDNA in alcohol-associated liver disease and liver cancer

Mitochondria are intracellular organelles responsible for energy production, glucose and lipid metabolism, cell death, cell proliferation, and innate immune response. Mitochondria are highly dynamic organelles that constantly undergo fission, fusion, and intracellular trafficking, as well as degradation and biogenesis. Mitochondrial dysfunction has been implicated in a variety of chronic liver diseases including alcohol-associated liver disease, metabolic dysfunction-associated steatohepatitis, and HCC. In this review, we provide a detailed overview of mitochondrial dynamics, mitophagy, and mitochondrial DNA-mediated innate immune response, and how dysregulation of these mitochondrial processes affects the pathogenesis of alcohol-associated liver disease and HCC. Mitochondrial dynamics and mitochondrial DNA-mediated innate immune response may thereby represent an attractive therapeutic target for ameliorating alcohol-associated liver disease and alcohol-associated HCC.

Exploring the Interplay between Mitochondrial DNA and Lifestyle Factors in the Pathogenesis of Psychiatric Disorders

The objectives of this study were to investigate the interaction of mitochondrial DNA (mtDNA) and lifestyle factors in the development of psychiatric disorders and to gain greater insight into their pathogenesis and comorbidity. We analyzed data from approximately 150,000 individuals from the UK Biobank. Mitochondrial gene-by-environment interaction studies (mtGEIS) were performed to assess the relationships between mtDNA and psychiatric disorders, such as anxiety, depression, and self-harm. These disorders were defined using diagnostic and severity indicators derived from the General Anxiety Disorder (GAD-7) and Patient Health Questionnaire (PHQ-9). Smoking and drinking behaviors were characterized based on UK Biobank criteria. For the mtGEIS, logistic and linear regression models from PLINK 2.0 were employed, accounting for covariates like age, sex, PC1-10, Townsend Deprivation Index (TDI), and educational attainment. We also conducted sex-stratified analyses to detect any gender-specific effects. Our findings highlighted significant associations between mtDNA and three psychiatric disorders. Moreover, the interplay between mtDNA and lifestyle factors showed significant associations with psychiatric disorders (all P values < 0.05). Specifically, two mutant loci, T5004C (B Anx_self = -0.0026, B Dep_self = -0.0024, B Self-harm = -0.0018) and G9123A (B Anx_self = -0.0030, B Dep_self = -0.0024, B Self-harm = -0.0017), were found to reduce the risk of three disorders after interacting with alcohol. Sex-specific differences were also observed. In summary, the expression of mitochondrial genes could be modulated by lifestyle factors like smoking and drinking, potentially affecting psychiatric disorders. These habits might influence mitochondrial respiratory chain activity and the replication and transcriptional regulation of mitochondrial genes, culminating in changes in mitochondrial functionality and subsequently psychiatric disorders.

Beneficial Effects of Low-Grade Mitochondrial Stress on Metabolic Diseases and Aging

Mitochondria function as platforms for bioenergetics, nutrient metabolism, intracellular signaling, innate immunity regulators, and modulators of stem cell activity. Thus, the decline in mitochondrial functions causes or correlates with diabetes mellitus and many aging-related diseases. Upon stress or damage, the mitochondria elicit a series of adaptive responses to overcome stress and restore their structural integrity and functional homeostasis. These adaptive responses to low-level or transient mitochondrial stress promote health and resilience to upcoming stress. Beneficial effects of low-grade mitochondrial stress, termed mitohormesis, have been observed in various organisms, including mammals. Accumulated evidence indicates that treatments boosting mitohormesis have therapeutic potential in various human diseases accompanied by mitochondrial stress. Here, we review multiple cellular signaling pathways and interorgan communication mechanisms through which mitochondrial stress leads to advantageous outcomes. We also discuss the relevance of mitohormesis in obesity, diabetes, metabolic liver disease, aging, and exercise.

The independent and joint risks of alcohol consumption, smoking, and excess weight on morbidity and mortality: a systematic review and meta-analysis exploring synergistic associations

OBJECTIVE

Alcohol consumption, smoking, and excess weight independently increase the risk of morbidity/mortality. Less is known about how they interact. This research aims to quantify the independent and joint associations of these exposures across health outcomes and identify whether these associations are synergistic.

STUDY DESIGN

The protocol for this systematic review and meta-analysis was pre-registered (PROSPERO CRD42021231443).

METHODS

Medline and Embase were searched between 1 January 2010 and 9 February 2022. Eligible peer-reviewed observational studies had to include adult participants from Organisation for Co-Operation and Development countries and report independent and joint associations between at least two eligible exposures (alcohol, smoking, and excess weight) and an ICD-10 outcome (or equivalent). For all estimates, we calculated the synergy index (SI) to identify whether joint associations were synergistic. Meta-analyses were conducted for outcomes with sufficiently homogenous data.

RESULTS

The search returned 26,290 studies, of which 98 were included. Based on 138,130 participants, the combined effect (SI) of alcohol and smoking on head and neck cancer death/disease was 3.78 times greater than the additive effect of each exposure (95% confidence interval [CI] = 2.61, 5.48). Based on 2,603,939 participants, the combined effect of alcohol and excess weight on liver disease/death was 1.55 times greater than the additive effect of each exposure (95% CI = 1.33, 1.82).

CONCLUSION

Synergistic associations suggest the true population-level risk may be underestimated. In the absence of bias, individuals with multiple risks would experience a greater absolute risk reduction from an intervention that targets a single exposure than individuals with a single risk.

Selective inhibition of the NLRP3 inflammasome protects against acute ethanol-induced cardiotoxicity in an FBXL2-dependent manner

Binge drinking exerts cardiac toxicity through various mechanisms, including oxidative stress and inflammation. NLRP3 inflammasomes possess both pro- and anti-inflammatory properties, although the role of NLRP3 in ethanol-induced cardiotoxicity remains unknown. This study is designed to examine the role of NLRP3 inflammasome in acute ethanol cardiotoxicity and the underlying mechanisms of action. Nine- to twelve-week-old adult male C57BL/6 mice are administered with ethanol (1.5 g/kg, twice daily, i.p.) for 3 days. A cohort of control and ethanol-challenged mice are treated with the NLRP3 inhibitor MCC950 (10 mg/kg/day, i.p., days 1 and 3). Myocardial geometry and function are monitored using echocardiography and cardiomyocyte edge-detection techniques. Levels of NLRP3 inflammasome, mitophagy and apoptosis are evaluated by western blot analysis and immunofluorescence techniques. Acute ethanol challenge results in abnormally higher cardiac systolic function, in conjunction with deteriorated cardiac diastolic function and cardiomyocyte contractile function. Levels of NLRP3 inflammasome and apoptosis are elevated, and mitophagy flux is blocked (elevated Pink1-Parkin and LC3B along with diminished p62 and Rab7) in mice receiving acute ethanol challenge. Although MCC950 does not elicit a notable effect on myocardial function, apoptosis or inflammasome activation in the absence of ethanol exposure, it effectively rescues acute ethanol cardiotoxicity, as manifested by restored myocardial and cardiomyocyte functional homeostasis, suppressed NLRP3 inflammasome activation and apoptosis, and improved mitophagy flux. Our data further suggest that FBXL2, an E3 ubiquitin ligase associated with mitochondrial homeostasis and mitophagy, is destabilized due to proteasomal degradation of caspase-1 by ethanol-induced hyperactivation of NLRP3-caspase-1 inflammasome signaling, resulting in mitochondrial injury and apoptosis. These findings denote a role for NLRP3 inflammasome in acute ethanol exposure-induced cardiotoxicity in an FBXL2-dependent manner and the therapeutic promise of targeting NLRP3 inflammasome for acute ethanol cardiotoxicity.

Effect of Ethanol Vapor Inhalation Treatment on Lethal Respiratory Viral Infection With Influenza A

Ethanol (EtOH) effectively inactivates enveloped viruses in vitro, including influenza and severe acute respiratory syndrome coronavirus 2. Inhaled EtOH vapor may inhibit viral infection in mammalian respiratory tracts, but this has not yet been demonstrated. Here we report that unexpectedly low EtOH concentrations in solution, approximately 20% (vol/vol), rapidly inactivate influenza A virus (IAV) at mammalian body temperature and are not toxic to lung epithelial cells on apical exposure. Furthermore, brief exposure to 20% (vol/vol) EtOH decreases progeny virus production in IAV-infected cells. Using an EtOH vapor exposure system that is expected to expose murine respiratory tracts to 20% (vol/vol) EtOH solution by gas-liquid equilibrium, we demonstrate that brief EtOH vapor inhalation twice a day protects mice from lethal IAV respiratory infection by reducing viruses in the lungs without harmful side effects. Our data suggest that EtOH vapor inhalation may provide a versatile therapy against various respiratory viral infectious diseases.

Astaxanthin Protects against Alcoholic Liver Injury via Regulating Mitochondrial Redox Balance and Calcium Homeostasis

Increasing evidence points to the critical role of calcium overload triggered by mitochondrial dysfunction in the development of alcoholic liver disease (ALD). As an important organelle for aerobic respiration with a double-layered membrane, mitochondria are pivotal targets of alcohol metabolism-mediated lipid peroxidation, wherein mitochondria-specific phospholipid cardiolipin oxidation to 4-hydroxynonenal (4-HNE) ultimately leads to mitochondrial integrity and function impairment. Therefore, it is absolutely essential to identify effective nutritional intervention targeting mitochondrial redox function for an alternative therapy of ALD, in order to compensate for the difficulty in achieving alcohol withdrawal due to addiction. In this study, we confirmed the significant advantages of astaxanthin (AX) against alcohol toxicity among various carotenoids via cell experiments and identified the potential in mitochondrion morphogenesis and calcium signaling pathway by bioinformatics analysis. The ALD model of Sprague-Dawley (SD) rats was also generated to investigate the effectiveness of AX on alcohol-induced liver injury, and the underlying mechanisms were further explored. AX intervention attenuated alcohol-induced oxidative stress and lipid peroxidation as well as mitochondrial dysfunction characterized by degenerative morphology changes and collapsed membrane potential. Also, AX reduced the production of 4-HNE by activating the Nrf2-ARE signaling pathway, which is closely associated with the redox balance of mitochondria. In addition, relieved mitochondrial Ca2+ accumulation caused by AX was observed both in vivo and in vitro. Furthermore, we revealed the structure-activity relationship of AX and mitochondrial membrane channel proteins MCU and VDAC1, implying potential acting targets. Altogether, our data indicated a new mechanism of AX intervention which protects against alcohol-induced liver injury through restoring redox balance and Ca2+ homeostasis in mitochondria, as well as provided novel insights into the development of AX as a therapeutic option for the management of ALD.

Total saponins from Panax japonicus attenuate acute alcoholic liver oxidative stress and hepatosteatosis by p62-related Nrf2 pathway and AMPK-ACC/PPARα axis in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Panax japonicus (T. Nees) C.A. Mey. (PJ) has been used as a tonic traditional Chinese medicine (TCM) for years. Based on its meridian tropism in liver, spleen, and lung, PJ was popularly used to enhance the function of these organs. It is originally recorded with detoxicant effect on binge drink in Ben Cao Gang Mu Shi Yi, a persuasive Chinese materia medica. And binge dink has a close relationship with alcoholic liver disease (ALD). Hence, it's meaningful to investigate whether PJ exerts liver protection against binge drink toxicity.

AIM OF THE STUDY

This investigation was carried out not only to emphasize the right recognition of total saponins from PJ (SPJ), but also to study on its sober-up effectiveness and defensive mechanism against acute alcoholic liver injury in vivo and in vitro.

MATERIALS AND METHODS

SPJ constituents were verified by HPLC-UV analysis. In vivo, acute alcoholic liver oxidative stress and hepatosteatosis were established by continuous ethanol gavage to C57BL/6 mice for 3 days. SPJ was pre-administered for 7 days to investigate its protective efficacy. Loss of righting reflex (LORR) assay was employed to assess anti-inebriation effect of SPJ. Transaminases levels and hematoxylin and eosin (H&E) staining were measured to indicate the alcoholic liver injury. Antioxidant enzymes were measured to evaluate the oxidative stress degree in liver. Measurement of hepatic lipid accumulation was based on Oil Red O staining. Levels of inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA). In vitro, HepG2 cells were treated with ethanol for 24 h, and SPJ was pre-administered for 2 h. 2,7-dichlorofluorescein diacetate (DCFH-DA) was used as a probe to indicate reactive oxygen species (ROS) generation. Nrf2 activation was verified by the favor of specific inhibitor, ML385. The nuclear translocation of Nrf2 was indicated with immunofluorescence analysis. Proteins expressions of related pathways were determined by Western blotting.

RESULTS

Oleanane-type saponins are the most abundant constituents of SPJ. In this acute model, SPJ released inebriation of mice in a dose dependent manner. It decreased levels of serum ALT and AST, and hepatic TG. Besides, SPJ inhibited CYP2E1 expression and reduced MDA level in liver, with upregulations of antioxidant enzymes GSH, SOD and CAT. p62-related Nrf2 pathway was activated by SPJ with downstream upregulations of GCLC and NQO1 in liver. AMPK-ACC/PPARα axis was upregulated by SPJ to alleviate hepatic lipidosis. Hepatic IL-6 and TNF-α levels were downregulated by SPJ, which indicated a regressive lipid peroxidation in liver. In HepG2 cells, SPJ reduced ethanol-exposed ROS generation. Activated p62-related Nrf2 pathway was verified to contribute to the alleviation of alcohol-induced oxidative stress in hepatic cells.

CONCLUSION

This attenuation of hepatic oxidative stress and steatosis suggested the therapeutic value of SPJ for ALD.

Ameliorative effect of diazepam against ethanol-induced mitochondrial disruption in brains of the mice

Brain oxidative damage and neurodegeneration by ethanol (ETH) are considered as important factors that triggered by oxidative stress. Recently, the abuse of diazepam (DZM) has increased by alcoholism-addicted patients. The present study evaluated the effects of combination treatment of ETH with DZM on oxidative damage induced in brain mitochondria of the mice. Only ETH (0.3, 0.6, and 2.5 g / kg) and ETH+ DZM (2.5 mg / kg) were administered intraperitoneally (ip) to the mice. Pathological changes and oxidative stress biomarkers including ROS, lipid peroxidation, carbonyl protein, mitochondrial function, and glutathione content were evaluated in brain mitochondria after 42 days. Results indicated that co-treatment of DZM and ETH significantly reduced mitochondrial toxicity, oxidative damage, pathological changes and increased level of glutathione. Subchronic ETH administration induced brain oxidative damage, mitochondrial disruption, and serious damage to the brain cells. Whereas, combination treatment improved oxidative damage, mitochondrial function, and pathological changes in brain cells after intoxication by ETH. These findings suggest antioxidant effect of DZM in combination with ETH and can be considered in reducing oxidative stress and mitochondrial damage attenuation in the brain. Combination therapy may be a better therapeutic candidate for prevention of brain oxidative damage induced by ETH.

Emerging roles and therapeutic potentials of ferroptosis: from the perspective of 11 human body organ systems

Since ferroptosis was first described as an iron-dependent cell death pattern in 2012, there has been increasing interest in ferroptosis research. In view of the immense potential of ferroptosis in treatment efficacy and its rapid development in recent years, it is essential to track and summarize the latest research in this field. However, few writers have been able to draw on any systematic investigation into this field based on human body organ systems. Hence, in this review, we provide a comprehensive description of the latest progress in unveiling the roles and functions, as well as the therapeutic potential of ferroptosis, in treating diseases from the aspects of 11 human body organ systems (including the nervous system, respiratory system, digestive system, urinary system, reproductive system, integumentary system, skeletal system, immune system, cardiovascular system, muscular system, and endocrine system) in the hope of providing references for further understanding the pathogenesis of related diseases and bringing an innovative train of thought for reformative clinical treatment.

Mechanisms of Lipid Droplet Accumulation in Steatotic Liver Diseases

The steatotic diseases of metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-associated liver disease (ALD), and chronic hepatitis C (HCV) account for the majority of liver disease prevalence, morbidity, and mortality worldwide. While these diseases have distinct pathogenic and clinical features, dysregulated lipid droplet (LD) organelle biology represents a convergence of pathogenesis in all three. With increasing understanding of hepatocyte LD biology, we now understand the roles of LD proteins involved in these diseases but also how genetics modulate LD biology to either exacerbate or protect against the phenotypes associated with steatotic liver diseases. Here, we review the history of the LD organelle and its biogenesis and catabolism. We also review how this organelle is critical not only for the steatotic phenotype of liver diseases but also for their advanced phenotypes. Finally, we summarize the latest attempts and challenges of leveraging LD biology for therapeutic gain in steatotic diseases. In conclusion, the study of dysregulated LD biology may lead to novel therapeutics for the prevention of disease progression in the highly prevalent steatotic liver diseases of MASLD, ALD, and HCV.

Stress mechanism involved in the progression of alcoholic liver disease and the therapeutic efficacy of nanoparticles

Alcoholic liver disease (ALD) poses a significant threat to human health, with excessive alcohol intake disrupting the immunotolerant environment of the liver and initiating a cascade of pathological events. This progressive disease unfolds through fat deposition, proinflammatory cytokine upregulation, activation of hepatic stellate cells, and eventual development of end-stage liver disease, known as hepatocellular carcinoma (HCC). ALD is intricately intertwined with stress mechanisms such as oxidative stress mediated by reactive oxygen species, endoplasmic reticulum stress, and alcohol-induced gut dysbiosis, culminating in increased inflammation. While the initial stages of ALD can be reversible with diligent care and abstinence, further progression necessitates alternative treatment approaches. Herbal medicines have shown promise, albeit limited by their poor water solubility and subsequent lack of extensive exploration. Consequently, researchers have embarked on a quest to overcome these challenges by delving into the potential of nanoparticle-mediated therapy. Nanoparticle-based treatments are being explored for liver diseases that share similar mechanisms with alcoholic liver disease. It underscores the potential of these innovative approaches to counteract the complex pathogenesis of ALD, providing new avenues for therapeutic intervention. Nevertheless, further investigations are imperative to fully unravel the therapeutic potential and unlock the promise of nanoparticle-mediated therapy specifically tailored for ALD treatment.

Stress mechanism involved in the progression of alcoholic liver disease and the therapeutic efficacy of nanoparticles

Alcoholic liver disease (ALD) poses a significant threat to human health, with excessive alcohol intake disrupting the immunotolerant environment of the liver and initiating a cascade of pathological events. This progressive disease unfolds through fat deposition, proinflammatory cytokine upregulation, activation of hepatic stellate cells, and eventual development of end-stage liver disease, known as hepatocellular carcinoma (HCC). ALD is intricately intertwined with stress mechanisms such as oxidative stress mediated by reactive oxygen species, endoplasmic reticulum stress, and alcohol-induced gut dysbiosis, culminating in increased inflammation. While the initial stages of ALD can be reversible with diligent care and abstinence, further progression necessitates alternative treatment approaches. Herbal medicines have shown promise, albeit limited by their poor water solubility and subsequent lack of extensive exploration. Consequently, researchers have embarked on a quest to overcome these challenges by delving into the potential of nanoparticle-mediated therapy. Nanoparticle-based treatments are being explored for liver diseases that share similar mechanisms with alcoholic liver disease. It underscores the potential of these innovative approaches to counteract the complex pathogenesis of ALD, providing new avenues for therapeutic intervention. Nevertheless, further investigations are imperative to fully unravel the therapeutic potential and unlock the promise of nanoparticle-mediated therapy specifically tailored for ALD treatment.

Antioxidants ameliorate oxidative stress in alcoholic liver injury by modulating lipid metabolism and phospholipid homeostasis

Alcoholic liver disease (ALD) is a significant risk factor in the global disease burden. The antioxidants vitamin C (Vc) and N-acetyl cysteine (NAC) have shown hepatoprotective effects in preventing and treating ALD. However, the correlation between the improved effect of antioxidants and lipid metabolism is still unclear. In this study, AML12 cells and C57BL/6 mice stimulated with alcohol were used to investigate the protective effects and potential mechanisms of two antioxidants (Vc and NAC) on alcoholic liver injury. Results showed that Vc and NAC attenuated intracellular lipid accumulation and oxidative damage induced by excessive alcohol exposure in hepatic AML12 cells. The in vivo results indicated that antioxidants ameliorated alcohol-induced changes in histopathology, reducing the levels of alcohol metabolizing factors and aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG), and total cholesterol (TC) contents, which demonstrated that antioxidants effectively mitigated liver injury in ALD mice. Further studies showed that antioxidants reversed the disruption of fatty acid (FA) synthesis and lipid transport induced by alcohol exposure, and restored phospholipid levels. Especially, Vc and NAC increased the endogenous antioxidant plasmenyl phosphatidylethanolamine (PlsEtn). Additionally, antioxidants ameliorated the alcohol-impaired mitochondrial function and inhibited excessive oxidative stress. In conclusion, antioxidants can regulate lipid metabolism and phospholipid homeostasis, which in turn inhibit oxidative stress and thereby exert protective effects against ALD.

Mitochondrial Metabolism: A New Dimension of Personalized Oncology

Energy is needed by cancer cells to stay alive and communicate with their surroundings. The primary organelles for cellular metabolism and energy synthesis are mitochondria. Researchers recently proved that cancer cells can steal immune cells' mitochondria using nanoscale tubes. This finding demonstrates the dependence of cancer cells on normal cells for their living and function. It also denotes the importance of mitochondria in cancer cells' biology. Emerging evidence has demonstrated how mitochondria are essential for cancer cells to survive in the harsh tumor microenvironments, evade the immune system, obtain more aggressive features, and resist treatments. For instance, functional mitochondria can improve cancer resistance against radiotherapy by scavenging the released reactive oxygen species. Therefore, targeting mitochondria can potentially enhance oncological outcomes, according to this notion. The tumors' responses to anticancer treatments vary, ranging from a complete response to even cancer progression during treatment. Therefore, personalized cancer treatment is of crucial importance. So far, personalized cancer treatment has been based on genomic analysis. Evidence shows that tumors with high mitochondrial content are more resistant to treatment. This paper illustrates how mitochondrial metabolism can participate in cancer resistance to chemotherapy, immunotherapy, and radiotherapy. Pretreatment evaluation of mitochondrial metabolism can provide additional information to genomic analysis and can help to improve personalized oncological treatments. This article outlines the importance of mitochondrial metabolism in cancer biology and personalized treatments.

In utero ethanol exposure induces mitochondrial DNA damage and inhibits mtDNA repair in developing brain

Introduction

Mitochondrial dysfunction is postulated to be a central event in fetal alcohol spectrum disorders (FASD). People with the most severe form of FASD, fetal alcohol syndrome (FAS) are estimated to live only 34 years (95% confidence interval, 31 to 37 years), and adults who were born with any form of FASD often develop early aging. Mitochondrial dysfunction and mitochondrial DNA (mtDNA) damage, hallmarks of aging, are postulated central events in FASD. Ethanol (EtOH) can cause mtDNA damage, consequent increased oxidative stress, and changes in the mtDNA repair protein 8-oxoguanine DNA glycosylase-1 (OGG1). Studies of molecular mechanisms are limited by the absence of suitable human models and non-invasive tools.

Methods

We compared human and rat EtOH-exposed fetal brain tissues and neuronal cultures, and fetal brain-derived exosomes (FB-Es) from maternal blood. Rat FASD was induced by administering a 6.7% alcohol liquid diet to pregnant dams. Human fetal (11-21 weeks) brain tissue was collected and characterized by maternal self-reported EtOH use. mtDNA was amplified by qPCR. OGG1 and Insulin-like growth factor 1 (IGF-1) mRNAs were assayed by qRT-PCR. Exosomal OGG1 was measured by ddPCR.

Results

Maternal EtOH exposure increased mtDNA damage in fetal brain tissue and FB-Es. The damaged mtDNA in FB-Es correlated highly with small eye diameter, an anatomical hallmark of FASD. OGG1-mediated mtDNA repair was inhibited in EtOH-exposed fetal brain tissues. IGF-1 rescued neurons from EtOH-mediated mtDNA damage and OGG1 inhibition.

Conclusion

The correlation between mtDNA damage and small eye size suggests that the amount of damaged mtDNA in FB-E may serve as a marker to predict which at risk fetuses will be born with FASD. Moreover, IGF-1 might reduce EtOH-caused mtDNA damage and neuronal apoptosis.

Mitochondrial metabolism: a predictive biomarker of radiotherapy efficacy and toxicity

INTRODUCTION

Radiotherapy is a mainstay of cancer treatment. Clinical studies revealed a heterogenous response to radiotherapy, from a complete response to even disease progression. To that end, finding the relative prognostic factors of disease outcomes and predictive factors of treatment efficacy and toxicity is essential. It has been demonstrated that radiation response depends on DNA damage response, cell cycle phase, oxygen concentration, and growth rate. Emerging evidence suggests that altered mitochondrial metabolism is associated with radioresistance.

METHODS

This article provides a comprehensive evaluation of the role of mitochondria in radiotherapy efficacy and toxicity. In addition, it demonstrates how mitochondria might be involved in the famous 6Rs of radiobiology.

RESULTS

In terms of this idea, decreasing the mitochondrial metabolism of cancer cells may increase radiation response, and enhancing the mitochondrial metabolism of normal cells may reduce radiation toxicity. Enhancing the normal cells (including immune cells) mitochondrial metabolism can potentially improve the tumor response by enhancing immune reactivation. Future studies are invited to examine the impacts of mitochondrial metabolism on radiation efficacy and toxicity. Improving radiotherapy response with diminishing cancer cells' mitochondrial metabolism, and reducing radiotherapy toxicity with enhancing normal cells' mitochondrial metabolism.

Effects of Antioxidants in Fermented Beverages in Tissue Transcriptomics: Effect of Beer Intake on Myocardial Tissue after Oxidative Injury

Fermented beverages, such as wine and beer, are rich in polyphenols that have been shown to have protective effects against oxidative stress. Oxidative stress plays a central role in the pathogenesis and progression of cardiovascular disease. However, the potential benefits of fermented beverages on cardiovascular health need to be fully investigated at a molecular level. In this study, we aimed at analyzing the effects of beer consumption in modulating the transcriptomic response of the heart to an oxidative stress challenge induced by myocardial ischemia (MI) in the presence of hypercholesterolemia in a pre-clinical swine model. Previous studies have shown that the same intervention induces organ protective benefits. We report a dose-dependent up-regulation of electron transport chain members and the down-regulation of spliceosome-associated genes linked to beer consumption. Additionally, low-dose beer consumption resulted in a down-regulation of genes associated with the immune response, that was not shown for moderate-dose beer consumption. These findings, observed in animals having demonstrated beneficial effects at the organ-level, indicate that the antioxidants in beer differentially affect the myocardial transcriptome in a dose-dependent manner.

The role of pyroptosis in inflammatory diseases

Programmed cell death has crucial roles in the physiological maturation of an organism, the maintenance of metabolism, and disease progression. Pyroptosis, a form of programmed cell death which has recently received much attention, is closely related to inflammation and occurs via canonical, non-canonical, caspase-3-dependent, and unclassified pathways. The pore-forming gasdermin proteins mediate pyroptosis by promoting cell lysis, contributing to the outflow of large amounts of inflammatory cytokines and cellular contents. Although the inflammatory response is critical for the body's defense against pathogens, uncontrolled inflammation can cause tissue damage and is a vital factor in the occurrence and progression of various diseases. In this review, we briefly summarize the major signaling pathways of pyroptosis and discuss current research on the pathological function of pyroptosis in autoinflammatory diseases and sterile inflammatory diseases.

Mitochondrial Dysfunction: At the Nexus between Alcohol-Associated Immunometabolic Dysregulation and Tissue Injury

Alcohol misuse, directly or indirectly as a result of its metabolism, negatively impacts most tissues, including four with critical roles in energy metabolism regulation: the liver, pancreas, adipose, and skeletal muscle. Mitochondria have long been studied for their biosynthetic roles, such as ATP synthesis and initiation of apoptosis. However, current research has provided evidence that mitochondria participate in myriad cellular processes, including immune activation, nutrient sensing in pancreatic β-cells, and skeletal muscle stem and progenitor cell differentiation. The literature indicates that alcohol impairs mitochondrial respiratory capacity, promoting reactive oxygen species (ROS) generation and disrupting mitochondrial dynamics, leading to dysfunctional mitochondria accumulation. As discussed in this review, mitochondrial dyshomeostasis emerges at a nexus between alcohol-disrupted cellular energy metabolism and tissue injury. Here, we highlight this link and focus on alcohol-mediated disruption of immunometabolism, which refers to two distinct, yet interrelated processes. Extrinsic immunometabolism involves processes whereby immune cells and their products influence cellular and/or tissue metabolism. Intrinsic immunometabolism describes immune cell fuel utilization and bioenergetics that affect intracellular processes. Alcohol-induced mitochondrial dysregulation negatively impacts immunometabolism in immune cells, contributing to tissue injury. This review will present the current state of literature, describing alcohol-mediated metabolic and immunometabolic dysregulation from a mitochondrial perspective.

Peripheral blood mononuclear cell mitochondrial dysfunction in acute alcohol-associated hepatitis

BACKGROUND

Patients with acute alcohol-associated hepatitis (AH) have immune dysfunction. Mitochondrial function is critical for immune cell responses and regulates senescence. Clinical translational studies using complementary bioinformatics-experimental validation of mitochondrial responses were performed in peripheral blood mononuclear cells (PBMC) from patients with AH, healthy controls (HC), and heavy drinkers without evidence of liver disease (HD).

METHODS

Feature extraction for differentially expressed genes (DEG) in mitochondrial components and telomere regulatory pathways from single-cell RNAseq (scRNAseq) and integrated 'pseudobulk' transcriptomics from PBMC from AH and HC (n = 4 each) were performed. After optimising isolation and processing protocols for functional studies in PBMC, mitochondrial oxidative responses to substrates, uncoupler, and inhibitors were quantified in independent discovery (AH n = 12; HD n = 6; HC n = 12) and validation cohorts (AH n = 10; HC n = 7). Intermediary metabolites (gas-chromatography/mass-spectrometry) and telomere length (real-time PCR) were quantified in subsets of subjects (PBMC/plasma AH n = 69/59; HD n = 8/8; HC n = 14/27 for metabolites; HC n = 13; HD n = 8; AH n = 72 for telomere length).

RESULTS

Mitochondrial, intermediary metabolite, and senescence-regulatory genes were differentially expressed in PBMC from AH and HC in a cell type-specific manner at baseline and with lipopolysaccharide (LPS). Fresh PBMC isolated using the cell preparation tube generated optimum mitochondrial responses. Intact cell and maximal respiration were lower (p ≤ .05) in AH than HC/HD in the discovery and validation cohorts. In permeabilised PBMC, maximum respiration, complex I and II function were lower in AH than HC. Most tricarboxylic acid (TCA) cycle intermediates in plasma were higher while those in PBMC were lower in patients with AH than those from HC. Lower telomere length, a measure of cellular senescence, was associated with higher mortality in AH.

CONCLUSION

Patients with AH have lower mitochondrial oxidative function, higher plasma TCA cycle intermediates, with telomere shortening in nonsurvivors.

Essential lipid autacoids rewire mitochondrial energy efficiency in metabolic dysfunction-associated fatty liver disease

BACKGROUND AND AIM

Injury to hepatocyte mitochondria is common in metabolic dysfunction-associated fatty liver disease. Here, we investigated whether changes in the content of essential fatty acid-derived lipid autacoids affect hepatocyte mitochondrial bioenergetics and metabolic efficiency.

APPROACH AND RESULTS

The study was performed in transgenic mice for the fat-1 gene, which allows the endogenous replacement of the membrane omega-6-polyunsaturated fatty acid (PUFA) composition by omega-3-PUFA. Transmission electron microscopy revealed that hepatocyte mitochondria of fat-1 mice had more abundant intact cristae and higher mitochondrial aspect ratio. Fat-1 mice had increased expression of oxidative phosphorylation complexes I and II and translocases of both inner (translocase of inner mitochondrial membrane 44) and outer (translocase of the outer membrane 20) mitochondrial membranes. Fat-1 mice also showed increased mitofusin-2 and reduced dynamin-like protein 1 phosphorylation, which mediate mitochondrial fusion and fission, respectively. Mitochondria of fat-1 mice exhibited enhanced oxygen consumption rate, fatty acid β-oxidation, and energy substrate utilization as determined by high-resolution respirometry, [1- 14 C]-oleate oxidation and nicotinamide adenine dinucleotide hydride/dihydroflavine-adenine dinucleotide production, respectively. Untargeted lipidomics identified a rich hepatic omega-3-PUFA composition and a specific docosahexaenoic acid (DHA)-enriched lipid fingerprint in fat-1 mice. Targeted lipidomics uncovered a higher content of DHA-derived lipid autacoids, namely resolvin D1 and maresin 1, which rescued hepatocytes from TNFα-induced mitochondrial dysfunction, and unblocked the tricarboxylic acid cycle flux and metabolic utilization of long-chain acyl-carnitines, amino acids, and carbohydrates. Importantly, fat-1 mice were protected against mitochondrial injury induced by obesogenic and fibrogenic insults.

CONCLUSION

Our data uncover the importance of a lipid membrane composition rich in DHA and its lipid autacoid derivatives to have optimal hepatic mitochondrial and metabolic efficiency.

Features of oxidative stress in alcoholism

The review considers molecular mechanisms underlying formation and development of oxidative stress (OS) in patients with alcohol dependence. The major attention is paid to the effects of ethanol and its metabolite acetaldehyde associated with additional sources of generation of reactive oxygen species (ROS) in response to exogenous ethanol. The own results of studies of the in vitro effect of ethanol and acetaldehyde on the concentration of peripheral OS markers - products of oxidative modification of proteins (protein carbonyls), lipids (lipid peroxidation products), DNA (8-hydroxy-2-deoxyguanosine, 8-OHdG) in blood plasma are presented. The changes in these parameters and the activity of antioxidant enzymes (SOD, catalase) in patients with alcohol dependence were analyzed. Own and literature data indicate that at a certain stage of the disease OS can play a protective rather than pathogenic role in the body.