Genetically encoded probiotic EcN 1917 alleviates alcohol-induced acute liver injury and restore gut microbiota homeostasis

Endogenous ethanol production in health and disease

The gut microbiome exerts metabolic actions on distal tissues and organs outside the intestine, partly through microbial metabolites that diffuse into the circulation. The disruption of gut homeostasis results in changes to microbial metabolites, and more than half of the variance in the plasma metabolome can be explained by the gut microbiome. Ethanol is a major microbial metabolite that is produced in the intestine of nearly all individuals; however, elevated ethanol production is associated with pathological conditions such as metabolic dysfunction-associated steatotic liver disease and auto-brewery syndrome, in which the liver's capacity to metabolize ethanol is surpassed. In this Review, we describe the mechanisms underlying excessive ethanol production in the gut and the role of ethanol catabolism in mediating pathogenic effects of ethanol on the liver and host metabolism. We conclude by discussing approaches to target excessive ethanol production by gut bacteria.

Engineered probiotics as live biotherapeutics for diagnosis and treatment of human diseases

The use of probiotics to regulate the intestinal microbiota to prevent and treat a large number of disorders and diseases has been an international research hotspot. Although conventional probiotics have a certain regulatory role in nutrient metabolism, inhibiting pathogens, inducing immune regulation, and maintaining intestinal epithelial barrier function, they are unable to treat certain diseases. In recent years, aided by the continuous development of synthetic biology, engineering probiotics with desired characteristics and functionalities to benefit human health has made significant progress. In this article, we summarise the mechanism of action of conventional probiotics and their limitations and highlight the latest developments in the design and construction of probiotics as living diagnostics and therapeutics for the detection and treatment of a series of diseases, including pathogen infections, cancer, intestinal inflammation, metabolic disorders, vaccine delivery, cognitive health, and fatty liver. Besides we discuss the concerns regarding engineered probiotics and corresponding countermeasures and outline the desired features in the future development of engineered live biotherapeutics.

Next generation probiotics: Engineering live biotherapeutics

The population dynamics of the human microbiome have been associated with inflammatory bowel disease, cancer, obesity, autoimmune diseases, and many other human disease states. An emerging paradigm in treatment is the administration of live engineered organisms, also called next-generation probiotics. However, the efficacy of these microbial therapies can be limited by the organism's overall performance in the harsh and nutrient-limited environment of the gut. In this review, we summarize the current state of the art use of bacterial and yeast strains as probiotics, highlight the recent development of genetic tools for engineering new therapeutic functions in these organisms, and report on the latest therapeutic applications of engineered probiotics, including recent clinical trials. We also discuss the supplementation of prebiotics as a method of manipulating the microbiome and improving the overall performance of engineered live biotherapeutics.

Investigating human-derived lactic acid bacteria for alcohol resistance

BACKGROUND

Excessive alcohol consumption has been consistently linked to serious adverse health effects, particularly affecting the liver. One natural defense against the detrimental impacts of alcohol is provided by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH), which detoxify harmful alcohol metabolites. Recent studies have shown that certain probiotic strains, notably Lactobacillus spp., possess alcohol resistance and can produce these critical enzymes. Incorporating these probiotics into alcoholic beverages represents a pioneering approach that can potentially mitigate the negative health effects of alcohol while meeting evolving consumer preferences for functional and health-centric products.

RESULTS

Five lactic acid bacteria (LAB) isolates were identified: Lactobacillus paracasei Alc1, Lacticaseibacillus rhamnosus AA, Pediococcus acidilactici Alc3, Lactobacillus paracasei Alc4, and Pediococcus acidilactici Alc5. Assessment of their alcohol tolerance, safety, adhesion ability, and immunomodulatory effects identified L. rhamnosus AA as the most promising alcohol-tolerant probiotic strain. This strain also showed high production of ADH and ALDH. Whole genome sequencing analysis revealed that the L. rhamnosus AA genome contained both the adh (encoding for ADH) and the adhE (encoding for ALDH) genes.

CONCLUSIONS

L. rhamnosus AA, a novel probiotic candidate, showed notable alcohol resistance and the capability to produce enzymes essential for alcohol metabolism. This strain is a highly promising candidate for integration into commercial alcoholic beverages upon completion of comprehensive safety and functionality evaluations.

Research progress on rodent models and its mechanisms of liver injury

The liver is the most important organ for biological transformation in the body and is crucial for maintaining the body's vital activities. Liver injury is a serious pathological condition that is commonly found in many liver diseases. It has a high incidence rate, is difficult to cure, and is prone to recurrence. Liver injury can cause serious harm to the body, ranging from mild to severe fatty liver disease. If the condition continues to worsen, it can lead to liver fibrosis and cirrhosis, ultimately resulting in liver failure or liver cancer, which can seriously endanger human life and health. Therefore, establishing an rodent model that mimics the pathogenesis and severity of clinical liver injury is of great significance for better understanding the pathogenesis of liver injury patients and developing more effective clinical treatment methods. The author of this article summarizes common chemical liver injury models, immune liver injury models, alcoholic liver injury models, drug-induced liver injury models, and systematically elaborates on the modeling methods, mechanisms of action, pathways of action, and advantages or disadvantages of each type of model. The aim of this study is to establish reliable rodent models for researchers to use in exploring anti-liver injury and hepatoprotective drugs. By creating more accurate theoretical frameworks, we hope to provide new insights into the treatment of clinical liver injury diseases.

Bifidobacterium lactis TY-S01 protects against alcoholic liver injury in mice by regulating intestinal barrier function and gut microbiota

Alcohol-induced liver injury poses a significant threat to human health. Probiotics have been proven to prevent and treat alcohol-induced liver injury. In this study, the preventive effect of Bifidobacterium lactis TY-S01 on alcohol-induced liver injury in mice was investigated. TY-S01 pretreatment effectively protected mice against alcohol-induced liver injury by preserving the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, triglyceride and high-density lipoprotein-cholesterol in serum and maintaining the levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-1β in liver tissue. Additionally, TY-S01 could maintain the endotoxin levels in serum, maintain the mRNA expression levels of zonula occluden-1, occludin, claudin-1 and claudin-3 in the gut, and prevent gut microbiota dysbiosis in mice with alcoholic liver injury. Spearman's correlation analysis revealed that there was a clear correlation among serum indicators, inflammatory cytokines and gut microbiota. In conclusion, TY-S01 attenuates alcohol-induced liver injury by protecting the integrity of the intestinal barrier and maintaining the balance of the gut microbiota.

Bifidobacterium lactis TY-S01 protects against alcoholic liver injury in mice by regulating intestinal barrier function and gut microbiota

Alcohol-induced liver injury poses a significant threat to human health. Probiotics have been proven to prevent and treat alcohol-induced liver injury. In this study, the preventive effect of Bifidobacterium lactis TY-S01 on alcohol-induced liver injury in mice was investigated. TY-S01 pretreatment effectively protected mice against alcohol-induced liver injury by preserving the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, triglyceride and high-density lipoprotein-cholesterol in serum and maintaining the levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-1β in liver tissue. Additionally, TY-S01 could maintain the endotoxin levels in serum, maintain the mRNA expression levels of zonula occluden-1, occludin, claudin-1 and claudin-3 in the gut, and prevent gut microbiota dysbiosis in mice with alcoholic liver injury. Spearman's correlation analysis revealed that there was a clear correlation among serum indicators, inflammatory cytokines and gut microbiota. In conclusion, TY-S01 attenuates alcohol-induced liver injury by protecting the integrity of the intestinal barrier and maintaining the balance of the gut microbiota.

Harnessing the potential of probiotics in the treatment of alcoholic liver disorders

In the current scenario, prolonged consumption of alcohol across the globe is upsurging an appreciable number of patients with the risk of alcohol-associated liver diseases. According to the recent report, the gut-liver axis is crucial in the progression of alcohol-induced liver diseases, including steatosis, steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Despite several factors associated with alcoholic liver diseases, the complexity of the gut microflora and its great interaction with the liver have become a fascinating area for researchers due to the high exposure of the liver to free radicals, bacterial endotoxins, lipopolysaccharides, inflammatory markers, etc. Undoubtedly, alcohol-induced gut microbiota imbalance stimulates dysbiosis, disrupts the intestinal barrier function, and trigger immune as well as inflammatory responses which further aggravate hepatic injury. Since currently available drugs to mitigate liver disorders have significant side effects, hence, probiotics have been widely researched to alleviate alcohol-associated liver diseases and to improve liver health. A broad range of probiotic bacteria like Lactobacillus, Bifidobacteria, Escherichia coli, Sacchromyces, and Lactococcus are used to reduce or halt the progression of alcohol-associated liver diseases. Several underlying mechanisms, including alteration of the gut microbiome, modulation of intestinal barrier function and immune response, reduction in the level of endotoxins, and bacterial translocation, have been implicated through which probiotics can effectively suppress the occurrence of alcohol-induced liver disorders. This review addresses the therapeutic applications of probiotics in the treatment of alcohol-associated liver diseases. Novel insights into the mechanisms by which probiotics prevent alcohol-associated liver diseases have also been elaborated.

Identification and hepatoprotective activity of total glycosides of paeony with high content of paeoniflorin extracted from Paeonia lactiflora Pall

The aims of this work were to obtain total glucosides of paeony (TGP) with high content of paeoniflorin and evaluate the hepo-protective properties of TGP. After optimization by response surface methodology, optimized conditions were as follows: extraction time 33.0 min, extraction temperature 48 °C, ethanol content 44%, and the yield of TGP was 47.68 mg/g. Moreover, under established macroporous resin purification, paeoniflorin content of TGP achieved 67.6% in 1.5 L scale-up verification experiment. Purified TGP (p-TGP) was further analyzed by UHPLC-Q-Orbitrap-MS/MS, and 35 compouds including paeoniflorin were identified. The obtained p-TGP effectively reduced biochemical indexes and inflammatory cytokines in liver tissue of acute alcoholic liver injury mice model. Depending on this work, TGP with definitive compound composition exhibited great protective effect against acute alcoholic liver injury in vivo. Furthermore, the finding of this work will be helpful to understand the relationship between compound composition and functional properties of Chinese herb extracts.

Advances in Escherichia coli Nissle 1917 as a customizable drug delivery system for disease treatment and diagnosis strategies

With the in-depth and comprehensive study of bacteria and their related ecosystems in the human body, bacterial-based drug delivery system has become an emerging biomimetic platform that can retain the innate biological functions. Benefiting from its good biocompatibility and ideal targeting ability as a biological carrier, Escherichia coli Nissle 1917 (ECN) has been focused on the treatment strategies of inflammatory bowel disease and tumor. The advantage of a bacterial carrier is that it can express exogenous protein while also acting as a natural capsule by releasing drug slowly as a result of its own colonization impact. In order to survive in harsh environments such as the digestive tract and tumor microenvironment, ECN can be modified or genetically engineered to enhance its function and host adaptability. The adoption of ECN carries or expresses drugs which are essential for accurate diagnosis and treatment. This review briefly describes the properties of ECN, the relationship between ECN and inflammation and tumor, and the strategy of using surface modification and genetic engineering to modify ECN as a delivery carrier for disease treatment.

Ganoderic acids-rich ethanol extract from Ganoderma lucidum protects against alcoholic liver injury and modulates intestinal microbiota in mice with excessive alcohol intake

Alcoholic liver injury is mainly caused by excessive alcohol consumption and has become a global public health problem threatening human health. It is well known that Ganoderma lucidum possesses various excellent beneficial effects on liver function and lipid metabolism. The purpose of this study was to evaluate the underlying protective effect and action mechanism of ganoderic acids-rich G. lucidum ethanol extract (GLE) on alcohol-induced liver injury in mice with excessive alcohol intake. Results showed that oral administration of GLE could obviously inhibit the abnormal increases of serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and also significantly protect the liver against alcohol-induced excessive hepatic lipid accumulation and pathological changes. In addition, alcohol-induced oxidative stress in liver was significantly ameliorated by the dietary intervention of GLE through reducing the hepatic levels of maleic dialdehyde (MDA) and lactate dehydrogenase (LDH), and increasing the hepatic levels of glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and alcohol dehydrogenase (ADH). Compared with the model group, GLE intervention significantly ameliorated the intestinal microbial disorder by elevating the relative abundance of Ruminiclostridium_9, Prevotellaceae_UCG-001, Oscillibacter, [Eubacterium]_xylanophilum_group, norank_f_Clostridiates_vadinBB60_group, GCA-900066225, Bilophila, Ruminococcaceae_UCG-009, norank_f_Desulfovibrionaceae and Hydrogenoanaerobacterium, but decreasing the proportion of Clostridium_sensu_stricto_1. Furthermore, liver metabolomic profiling suggested that GLE intervention had a significant regulatory effect on the composition of liver metabolites in mice with excessive alcohol intake, especially the levels of some biomarkers involved in primary bile acid biosynthesis, riboflavin metabolism, tryptophan metabolism, biosynthesis of unsaturated fatty acids, fructose and mannose metabolism, glycolysis/gluconeogenesis. Additionally, dietary supplementation with GLE significantly regulated the mRNA levels of key genes related to fatty acids metabolism, ethanol catabolism and inflammatory response in liver. Conclusively, these findings indicate that GLE has a potentially beneficial effect on alleviating alcohol-induced liver injury and may be developed as a promising functional food ingredient.

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Phytochemical analysis revealed that ethanol extract of Gaoderma lucidum (GLE) is rich in ganoderic acids.

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GLE ameliorated lipid metabolism, antioxidant function and inflammatory response in mice with excessive alcohol intake.

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Liver metabolomics based on UPLC-QTOF/MS was performed to reveal the underlying hepatoprotective effect of GLE.

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GLE intervention alleviated alcoholic liver injury partly through regulating the “gut-liver-metabolite”axis.

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Hepatic gene transcriptions related to lipid metabolism and inflammation were remarkablyinfluenced by GLE intervention.