Hepatoprotective effects of Lactobacillus plantarum C88 on LPS/D-GalN–induced acute liver injury in mice

Bifidobacterium animalis A12 and Lactobacillus salivarius M18-6 Alleviate Alcohol Injury by keap1-Nrf2 Pathway and Thioredoxin System

Excessive drinking can significantly damage people's health and well-being. Although some lactic acid bacterial strains have been previously shown to alleviate the symptoms of alcohol injury, the mechanism underlying these effects remains unclear. The aim of this study was to establish an alcohol injury model and examine the protective effect and mechanism of B. animalis A12 and L. salivarius M18-6. The results showed that A12 freeze-dried powder could maintain the survival rate of mice with alcohol injury at 100%. Compared with Alco group, L. salivarius M18-6 dead cell improved the survival rate of mice, attenuated liver steatosis, and significantly down-regulated serum Alanine transaminase (ALT) level; at the same time, it activated keap1-Nrf2 signaling pathway and up-regulated Superoxide dismutase (SOD), it protects mouse liver cells from oxidative stress induced by alcohol injury. In addition, B. animalis A12 can reduce the stress response to short-term alcohol intake and improve the ability of anti-oxidative stress by upregulating the level of isobutyric acid, reducing the level of keap1 protein in the liver of mice and upregulating the expression of thioredoxin genes (Txnrd1, Txnrd3, Txn1). Taken together, the results showed that B. animalis A12 and L. salivarius M18-6 alleviate alcohol injury in mice through keap1-Nrf2 signaling pathway and thioredoxin system.

Hepatoprotective Effect of Kaempferol: A Review of the Dietary Sources, Bioavailability, Mechanisms of Action, and Safety

The liver is the body's most critical organ that performs vital functions. Hepatic disorders can affect the physiological and biochemical functions of the body. Hepatic disorder is a condition that describes the damage to cells, tissues, structures, and functions of the liver, which can cause fibrosis and ultimately result in cirrhosis. These diseases include hepatitis, ALD, NAFLD, liver fibrosis, liver cirrhosis, hepatic failure, and HCC. Hepatic diseases are caused by cell membrane rupture, immune response, altered drug metabolism, accumulation of reactive oxygen species, lipid peroxidation, and cell death. Despite the breakthrough in modern medicine, there is no drug that is effective in stimulating the liver function, offering complete protection, and aiding liver cell regeneration. Furthermore, some drugs can create adverse side effects, and natural medicines are carefully selected as new therapeutic strategies for managing liver disease. Kaempferol is a polyphenol contained in many vegetables, fruits, and herbal remedies. We use it to manage various diseases such as diabetes, cardiovascular disorders, and cancers. Kaempferol is a potent antioxidant and has anti-inflammatory effects, which therefore possesses hepatoprotective properties. The previous research has studied the hepatoprotective effect of kaempferol in various hepatotoxicity protocols, including acetaminophen (APAP)-induced hepatotoxicity, ALD, NAFLD, CCl₄, HCC, and lipopolysaccharide (LPS)-induced acute liver injury. Therefore, this report aims to provide a recent brief overview of the literature concerning the hepatoprotective effect of kaempferol and its possible molecular mechanism of action. It also provides the most recent literature on kaempferol's chemical structure, natural source, bioavailability, and safety.

Lactobacillus plantarum S9 alleviates lipid profile, insulin resistance, and inflammation in high-fat diet-induced metabolic syndrome rats

Probiotics are considered to play an crucial role in the treatment of high-fat diet (HFD)-induced lipid metabolic diseases, including metabolic syndrome (MS). This study aimed to investigate the effects of Lactobacillus plantarum S9 on MS in HFD-fed rats, and to explore the underlying role of probiotics in the treatment of MS. Sprague-Dawley rats were fed with HFD for 8 weeks, followed by the treatment of L. plantarum S9 for 6 weeks, and The body weight and blood glucose level of rats were detected on time. The results showed that L. plantarum S9 significantly decreased the body weight gain, Lee’s index, and liver index. Additionally, L. plantarum S9 reduced the levels of serum lipids and insulin resistance. L. plantarum S9 also decreased the levels of alanine aminotransferase (ALT) and aspartate transaminase (AST) in liver. Moreover, the serum levels of MS-related inflammatory signaling molecules, including lipopolysaccharide (LPS) and tumor necrosis factor-α (TNF-α), were significantly elevated. Western blot analysis showed that L. plantarum S9 inhibited the activation of nuclear factor-κB (NF-κB) pathway, decreased the expression level of Toll-like receptor 4 (TLR4), suppressed the activation of inflammatory signaling pathways, and reduced the expression levels of inflammatory factors in HFD-fed rats. Moreover, it further decreased the ratios of p-IκBα/IκBα, p-p65/NF-κB p65, and p-p38/p38. In summary, L. plantarum S9, as a potential functional strain, prevents or can prevent onset of MS.

<em>Lactobacillus plantarum</em> Lp2 improved LPS-induced liver injury through the TLR-4/MAPK/NFκB and Nrf2-HO-1/CYP2E1 pathways in mice

Background: Inflammatory liver diseases present a significant public health problem. Probiotics are a kind of living microorganisms, which can improve the balance of host intestinal flora, promote the proliferation of intestinal beneficial bacteria, inhibit the growth of harmful bacteria, improve immunity, reduce blood lipids and so on. Probiotics in fermented foods have attracted considerable attention lately as treatment options for liver injury. Objective: The aim of this study was selected probiotic strain with well probiotic properties from naturally fermented foods and investigated the underlying mechanisms of screened probiotic strain on lipopolysaccharide (LPS)-induced liver injury, which provided the theoretical foundation for the development of probiotics functional food. Design: The probiotic characteristics of Lactobacillus plantarum Lp2 isolated from Chinese traditional fermented food were evaluated. Male KM mice were randomly assigned into three groups: normal chow (Control), LPS and LPS with L. plantarum Lp2. L. plantarum Lp2 were orally administered for 4 weeks before exposure to LPS. The liver injury of LPS-induced mice was observed through the evaluation of biochemical indexes, protein expression level and liver histopathology. Results and discussions: After treatment for 4 weeks, L. plantarum Lp2 administration significantly reduced the LPS-induced liver coefficient and the levels of serum or liver aspartate transaminase (AST), alanine aminotransferase (ALT), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6) and LPS, as well as decreasing the histological alterations and protein compared with the LPS group. Western-blotting results showed that L. plantarum Lp2 activated the signal pathway of TLR4/MAPK/NFκB/NRF2-HO-1/CYP2E1/Caspase-3 and regulated the expression of related proteins. Conclusions: In summary, L. plantarum Lp2 suppressed the LPS-induced activation of inflammatory pathways, oxidative injury and apoptosis has the potential to be used to improve liver injury.

Lactobacillus paracasei CCFM1223 Protects against Lipopolysaccharide-Induced Acute Liver Injury in Mice by Regulating the “Gut–Liver” Axis

Background: Lactobacillus paracasei CCFM1223, a probiotic previously isolated from the healthy people’s intestine, exerts the beneficial influence of preventing the development of inflammation. Methods: The aim of this research was to explore the beneficial effects of L. paracasei CCFM1223 to prevent lipopolysaccharide (LPS)-induced acute liver injury (ALI) and elaborate on its hepatoprotective mechanisms. Results: L. paracasei CCFM1223 pretreatment remarkably decreased the activities of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mice with LPS treatment and remarkably recovered LPS-induced the changes in inflammatory cytokines (tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), interleukin (IL)-1β, IL-6, IL-17, IL-10, and LPS) and antioxidative enzymes activities (total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT)). Metagenomic analysis showed that L. paracasei CCFM1223 pretreatment remarkably increased the relative abundance of Catabacter compared with the LPS group but remarkably reduced the relative abundance of [Eubacterium] xylanophilumgroup, ASF356, LachnospiraceaeNK4A136group, and Lachnoclostridium, which is closely associated with the inflammation cytokines and antioxidative enzymes. Furthermore, L. paracasei CCFM1223 pretreatment remarkably increased the colonic, serum, and hepatic IL-22 levels in ALI mice. In addition, L. paracasei CCFM1223 pretreatment remarkably down-regulated the hepatic Tlr4 and Nf-kβ transcriptions and significantly up-regulated the hepatic Tlr9, Tak1, Iκ-Bα, and Nrf2 transcriptions in ALI mice. Conclusions: L. paracasei CCFM1223 has a hepatoprotective function in ameliorating LPS-induced ALI by regulating the “gut–liver” axis.

The Protective Effects of a Modified Xiaohua Funing Decoction against Acute Liver Failure in Mice Induced by D-Gal and LPS

Objective

The aim of this study was to evaluate the effects of a modified Xiaohua Funing decoction (Xfd) on acute liver failure (ALF) and determine whether the protective mechanisms are related to alterations in the gut microbiota.

Methods

An animal model of ALF was induced by intraperitoneal injection of D-galactosamine (D-Gal, 0.5 g/kg) and lipopolysaccharide (LPS, 100 μg/kg). Male BALB/c mice were randomly divided into the following 4 groups: the control group (saline, Con), model group (D-Gal/LPS, Mod), silymarin pretreatment group (200 mg/kg, Sil), and modified Xfd pretreatment group (650 mg/kg, Xfd). The Sil and Xfd groups received the respective intervention orally for 14 days and 2 h before D-Gal/LPS treatment. The liver injury markers included alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and liver histology. 16S rRNA gene sequencing was performed to assess the effects on the caecum content.

Results

D-Gal/LPS treatment caused severe ALF, illustrating that the ALF model was successfully established. The administration of Sil and Xfd greatly reduced the serum ALT and AST levels and improved the pathological signs of liver injury. However, no significant difference was found between the two groups. In contrast to the Mod group, the Sil and Xfd groups showed a shift toward the Con group in terms of the gut microbiota structure. The abundances of Firmicutes and Bacteroidetes and the Bacteroidetes/Firmicutes ratio in the Mod group significantly differed from those in the Con group. The Sil and Xfd groups showed restoration of the disordered microbiota. Significantly increased relative abundances of Lachnospiraceae_NK4A136_group and Candidatus_Saccharimonas and a markedly decreased Muribaculaceae abundance were found in the Sil and Xfd mice compared with those in the Mod mice (P < 0.01, P < 0.05). Interestingly, a negative correlation was observed between the abundances of the gut microbiota constituents, specifically Clostridia_UCG-014, and ALT and AST levels.

Conclusion

In summary, our results indicate that Xfd may protect the liver and modify the gut microbiota in ALF mice.

The Protective Effects of Lactobacillus plantarum KLDS 1.0344 on LPS-Induced Mastitis In Vitro and In Vivo

Cow mastitis, which significantly lowers milk quality, is mainly caused by pathogenic bacteria such as E. coli. Previous studies have suggested that lactic acid bacteria can have antagonistic effects on pathogenic bacteria that cause mastitis. In the current study, we evaluated the in vitro and in vivo alleviative effects of L. plantarum KLDS 1.0344 in mastitis treatment. In vitro antibacterial experiments were performed using bovine mammary epithelial cell (bMEC), followed by in vivo studies involving mastitis mouse models. In vitro results indicate that lactic acid was the primary substance inhibiting the E. coli pathogen. Meanwhile, treatment with L. plantarum KLDS 1.0344 can reduce cytokines' mRNA expression levels in the inflammatory response of bMEC induced by LPS. In vivo, the use of this strain reduced the secretion of inflammatory factors IL-6, IL-1β, and TNF-α, and decreased the activity of myeloperoxidase (MPO), and inhibited the secretion of p-p65 and p-IκBα. These results indicate that L. plantarum KLDS 1.0344 pretreatment can reduce the expression of inflammatory factors by inhibiting the activation of NF-κB signaling pathway, thus exerting prevent the occurrence of inflammation in vivo. Our findings show that L. plantarum KLDS 1.0344 has excellent properties as an alternative to antibiotics and can be developed into lactic acid bacteria preparation to prevent mastitis disease.

Pediococcus pentosaceus PP04 improves high-fat diet-induced liver injury by the modulation of gut inflammation and intestinal microbiota in C57BL/6N mice

In this study, Pediococcus pentococcus PP04 (PP04) isolated from the Northeast pickled cabbage was given to C57BL/6N mice for eight weeks, aiming to investigate the ameliorative effects of PP04 on liver injury induced by a high-fat diet. The western blot results suggested that PP04 ameliorated the increase of intestinal permeability by dramatically increasing the expressions of tight junction proteins, such as Occludin, Claudin-1 and ZO-1, which decreased hepatic lipopolysaccharides (LPS), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) concentrations to effectively alleviate the liver injury. Furthermore, PP04 relieved the high-fat diet-caused gut inflammation by the NF-κB/Nrf2 signaling pathway, which regulated the expression of inflammatory cytokines and antioxidants, to positively improve the liver injury. In addition, the 16S rDNA sequencing results inferred that PP04 had the potential to rebalance intestinal flora disorders through regulating the relative abundance of inflammation and obesity-related bacteria in mice.

Radioprotective effect of radiation-induced Lactococcus lactis cell-free extract against 60Coγ injury in mice

Ionizing radiation (IR) is widely used in the diagnosis and treatment of various cancers. However, IR can cause damage to human health by producing reactive oxygen species. Lactococcus lactis is a type of microorganism that is beneficial to human health and has a strong antioxidant capacity. In this study, the protective effect of normal and IR-induced L. lactis IL1403 cell-free extracts (CFE and IR-CFE, respectively) against oxidative damage in vitro and the radioprotective effect of IR-CFE in vivo was evaluated using ⁶⁰Coγ-induced oxidative damage model in mice. Results showed that IR-CFE exhibited a stronger oxidative damage-protective effect than CFE for L. lactis IL1403 under H₂O₂ in vitro. Moreover, IR-CFE also showed strong radioprotective effect on hepatocyte cells (AML-12) under radiation condition, and the effect was better than that of CFE. Animal experiment indicated that IR-CFE could reduce the IR-induced damage to the hematopoietic system by increasing the number of white blood cells and red blood cells in peripheral blood of irradiated mice. It was also observed that IR-CFE could markedly alleviate the ⁶⁰Coγ-induced oxidative stress via increasing the activities of superoxide dismutase and glutathione peroxidase, enhancing the levels of glutathione, and decreasing the contents of malondialdehyde in serum, liver, and spleen. In addition, IR-CFE also could reduce the activities of alanine transaminase and aspartate aminotransferase in serum, thereby reducing radiation damage to the liver. These results suggested that IR-CFE could be considered as potential candidates for natural radioprotective agents. This study provides a theoretical basis for improving the application of lactic acid bacteria.

Lactobacillus plantarum Y44 alleviates oxidative stress by regulating gut microbiota and colonic barrier function in Balb/C mice with subcutaneous d-galactose injection

Probiotics have been proved to ameliorate the symptoms of the host induced by oxidative stress. In this study, the protective effects of Lactobacillus plantarum Y44 on Balb/C mice injured by d-galactose (d-gal)-injection were examined. Six weeks of continuous subcutaneous d-gal injection caused liver and colon injury of the Balb/C mice. L. plantarum Y44 administration significantly reversed the injury by modulating hepatic protein expressions related to the Nrf-2/Keap-1 pathway, and enhancing expressions of colonic tight junction proteins. L. plantarum Y44 administration restored the d-gal injection-induced gut microbiota imbalance by manipulating the ratio of Firmicutes/Bacteroidetes (F/B) and Proteobacteria relative abundance at the phylum level, and manipulating relative abundances of Lactobacillaceae, Muribaculaceae, Ruminococcaceae, Desulfovibrionaceae, and Prevotellaceae at the family level. Moreover, the d-gal injection-induced glycerophospholipid metabolism disorder was ameliorated, evidenced by the decline of phosphatidyl ethanolamine (PE), phosphatidylcholine (PC), phosphatidyl serine (PS), and lysophosphatidyl choline (LysoPC) levels in the serum of the mice after the L. plantarum Y44 administration. Spearman correlation analysis revealed a significant correlation between changes in gut microbiota composition, glycerophospholipid levels, and oxidative stress-related indicators. In summary, L. plantarum Y44 administration ameliorated d-gal injection-induced oxidative stress in Balb/C mice by manipulating gut microbiota and intestinal barrier function, and further influenced the glycerophospholipid metabolism and hepatic Nrf-2/Keap-1 pathway-related protein expressions.

Lactobacillus plantarum LP33 attenuates Pb-induced hepatic injury in rats by reducing oxidative stress and inflammation and promoting Pb excretion

Lead (Pb) is one of the most common heavy metals and is harmful to human health. The liver is considered as a major target organ for Pb poisoning. Although probiotics have been shown to alleviate liver injury, the protective effect of Lactobacillus plantarum LP33 (LP33) against Pb-induced hepatotoxicity remains unclear. In order to explore the hepatoprotective effect of LP33, LP33 was administered to Pb-intoxicated Sprague-Dawley rats once daily by oral gavage for 8 weeks. The present results showed that LP33 supplementation alleviated liver injury, and inhibited oxidative stress and inflammation in Pb-exposed rats. Treatment with LP33 also promoted the phosphorylation of adenosine monophosphate-activated protein kinase and protein kinase B, activated nuclear factor erythroid 2-related factor 2 signaling and inhibited the activation of nuclear factor-κB signaling in liver tissues of rats exposed to Pb. Additionally, LP33 exhibited adequate Pb-binding capacity and satisfactory survival under simulated gastrointestinal conditions in vitro, and promoted Pb excretion via enterohepatic circulation of bile acids. This study demonstrated that LP33 reduced Pb-induced oxidative stress and inflammation and promoted Pb excretion, thereby attenuating the Pb-induced hepatic injury. Our findings suggest that LP33 supplementation may be a potential strategy for the treatment of Pb-induced hepatic toxicity.

Lactobacillus plantarum NA136 ameliorates nonalcoholic fatty liver disease by modulating gut microbiota, improving intestinal barrier integrity, and attenuating inflammation

Gut microbiota dysbiosis, associated with insulin resistance, weak intestinal barrier integrity, and inflammation, may also play a role in the development of dietary-induced nonalcoholic fatty liver disease (NAFLD). This study investigates the effects of dietary Lactobacillus plantarum NA136 administration on gut microbiota composition in an insulin-resistant C57BL/6J mouse NAFLD model. Comparison of mice with and without L. plantarum NA136 treatment revealed that L. plantarum NA136 treatment not only relieved insulin resistance but also significantly increased relative proportions of Desulfovibrio, Alistipes, Prevotella, and Enterorhabdus in gut microbiota of NAFLD mice. Meanwhile, L. plantarum NA136 administration also inhibited pathogenic bacterial growth, while promoting growth of probiotics such as Allobaculum, Lactobacillus, and, most markedly, Bifidobacterium. Moreover, L. plantarum NA136 treatment of NAFLD mice improved intestinal barrier integrity and attenuated high-fat and fructose diet (HFD/F)-induced inflammation. These results implicate gut-liver-axis-dependent microbiota modulation as the underlying mechanism for L. plantarum NA136-induced amelioration of NAFLD.Key points• L. plantarum NA136 corrects gut microbiota disorders caused by a high-fat and fructose diet. • L. plantarum NA136 strengthens the intestinal barrier and reduces inflammation in the liver. • L. plantarum NA136 relieves NAFLD by improving the gut-liver axis.

Lactobacillus fermentum HFY06 reduced CCl4-induced hepatic damage in Kunming mice

This study was conducted to investigate the preventative effect of Lactobacillus fermentum HFY06 on carbon tetrachloride (CCl₄)-induced liver injury in Kunming mice. Mice were treated with HFY06, then liver damage was induced using CCl₄. Evaluation indicators included the activities of aspartate aminotransferase (AST), triglycerides (TG), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) in serum; cytokines levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in serum; and related gene expressions of nuclear factor-κB (NF-κB), TNF-α, cyclooxygenase-2 (COX-2), copper/zinc superoxide dismutase (Cu/Zn-SOD), manganese superoxide dismutase (Mn-SOD), and catalase (CAT). Liver tissue was stained with hematoxylin and eosin for pathological analysis. Compared with the model group, HFY06 reduced the liver index, increased the serum SOD and GSH-Px activities, and reduced the AST, TG, and MDA activities in the mice. Inflammation-related IL-6, TNF-α and IFN-γ levels were also reduced after treatment with a high dose of HFY06. Pathological observation showed that CCl₄ damaged the mouse livers, which were significantly improved after treatment with silymarin and HFY06. qPCR also confirmed that the high dose of HFY06 (10⁹ colony-forming units [CFU] per kg per day) upregulated the mRNA expression of the antioxidant genes, Cu/Zn-SOD, Mn-SOD, and CAT, in the liver tissue and downregulated the mRNA expression of the inflammatory factors, NF-κB, TNF-α and COX-2, but HFY06 was less effective than silymarin. These findings indicate that HFY06 prevented CCl₄-induced liver damage in vivo but was less effective than silymarin. Thus, HFY06 may have a potential role in treating liver diseases.

This study was conducted to investigate the preventative effect of Lactobacillus fermentum HFY06 on carbon tetrachloride (CCl₄)-induced liver injury in Kunming mice.

Lactobacillus reuteri ZJ617 Culture Supernatant Attenuates Acute Liver Injury Induced in Mice by Lipopolysaccharide

BACKGROUND

Lactobacillus rhamnosus GG culture supernatant (LGGs) promotes intestinal integrity and ameliorates acute liver injury induced by alcohol in mice.

OBJECTIVES

The aim of this study was to investigate the protective effects and molecular mechanisms of Lactobacillus reuteri ZJ617 culture supernatant (ZJ617s) on acute liver injury induced by lipopolysaccharide (LPS) in mice.

METHODS

Male C57BL/6 mice (20 ± 2 g, 8 wk old) were randomly divided into 4 groups (6 mice/group): oral inoculation with phosphate-buffered saline (control), intraperitoneal injection of LPS (10 mg/kg body weight) (LPS), oral inoculation with ZJ617s 2 wk before intraperitoneal injection of LPS (ZJ617s + LPS), or oral inoculation with LGGs 2 wk before intraperitoneal injection of LPS (LGGs + LPS). Systemic inflammation, intestinal integrity, biomarkers of hepatic function, autophagy, and apoptosis signals in the liver were determined.

RESULTS

Twenty-four hours after LPS injection, the activities of serum alanine transaminase and aspartate transaminase were 32.2% and 30.3% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05). The ZJ617s + LPS group exhibited higher intestinal expression of claudin 3 (62.5%), occludin (60.1%), and zonula occludens 1 (60.5%) compared with the LPS group (P < 0.05). The concentrations of hepatic interleukin-6 and tumor necrosis factor-α were 21.4% and 27.3% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05). However, the concentration of interleukin-10 was 22.2% higher in the ZJ617s + LPS group. LPS increased the expression of Toll-like receptor 4 (TLR4; by 50.5%), phosphorylation p38 mitogen-activated protein kinase (p38MAPK; by 57.1%), extracellular signal-regulated kinase (by 77.8%), c-Jun N-terminal kinase (by 42.9%), and nuclear factor-κB (NF-κB; by 36.0%) compared with the control group. Supplementation with ZJ617s or LGGs ameliorated these effects (P < 0.05). Moreover, the hepatic expression of active caspase-3 and microtubule-associated protein 1 light chain 3 II was 23.8% and 28.6% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05).

CONCLUSIONS

ZJ617s exerts beneficial effects on the mouse liver through suppression of hepatic TLR4/MAPK/NF-κB activation, apoptosis, and autophagy. This trial was registered at Zhejiang University (http://www.lac.zju.edu.cn) as NO.ZJU20170529.

Exopolysaccharides from Lactobacillus buchneri TCP016 Attenuate LPS- and d-GalN-Induced Liver Injury by Modulating the Gut Microbiota

Liver diseases alter the gut microbiota, but several lactic acid bacteria can reduce the degree of liver damage. The present study investigated whether Lactobacillus buchneri TCP016 reduces the degree of liver damage by modifying the gut microbiota via its exopolysaccharides (EPSs). First, it was illustrated that the main EPS (EPS016; molecular weight = 8.509 × 10⁴ Da) comprised rhamnose, xylose, glucosamine, glucuronic acid, galactose, galacturonic acid, glucose, and mannose in molar ratios of 9.2:3.9:3.8:2.8:2.1:2.0:1.6:1.0. Our data showed that EPS016 alleviated the increase in plasma and hepatic enzyme and cytokine levels, increased superoxide dismutase and glutathione activity, and alleviated bacterial translocation to the liver and mesenteric lymph nodes in vivo. Furthermore, EPS016 ameliorated intestinal mucosal injury and gut flora dysbiosis, thereby decreasing the enrichment of Helicobacteraceae, Lachnospiraceae, and Enterobacteriaceae and increasing the abundance of Lactobacillus, Rikenellaceae, Bacteroidaceae, Bacteroidales_S24-7_group, and Prevotellaceae. These findings indicated that EPS016 inhibits lipopolysaccharides/d-galactosamine-induced liver injury and improves the modification of the gut microbiota.

Hepatoprotective Effect of the Ethanol Extract of Illicium henryi against Acute Liver Injury in Mice Induced by Lipopolysaccharide

The root bark of Illicium henryi has been used in traditional Chinese medicine to treat lumbar muscle strain and rheumatic pain. Its ethanol extract (EEIH) has been previously reported to attenuate lipopolysaccharide (LPS)-induced acute kidney injury in mice. The present study aimed to evaluate the in vitro antioxidant activities and in vivo protective effects of EEIH against LPS-induced acute liver injury (ALI) in mice as well as explore its molecular mechanisms. The mice were injected intraperitoneally (i.p.) with EEIH at the doses of 1.25, 2.5, and 5.0 mg/kg every day for 5 days. One hour after the last administration, the mice were administered i.p. with LPS (8 mg/kg). After fasting for 12 h, blood and liver tissues were collected to histopathological observation, biochemical assay, enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot analyses. EEIH possessed 2,2-diphenyl-1-picrylhydrazil (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiozoline-6-sulfonic acid) disodium salt (ABTS) radical scavenging activities and ferric-reducing antioxidant capacity in vitro. The histopathological examination, serum biochemical analysis, and liver myeloperoxidase (MPO) activity showed that EEIH pretreatment alleviated LPS-induced liver injury in mice. EEIH significantly dose-dependently decreased the mRNA and protein expression levels of inflammatory factors TNF-α, IL-1β, IL-6, and COX-2 in liver tissue of LPS-induced ALI mice via downregulating the mRNA and protein expressions of toll-like receptor 4 (TLR4) and inhibiting the phosphorylation of nuclear factor-κB (NF-κB) p65. Furthermore, EEIH markedly ameliorated liver oxidative and nitrosative stress burden in LPS-treated mice through reducing the content of thiobarbituric acid reactive substances (TBARS), inducible nitric oxide synthase (iNOS), and nitric oxide (NO) levels, restoring the decreased superoxide dismutase (SOD) and reduced glutathione (GSH) levels, and up-regulating nuclear factor erythroid 2 related factor 2 (Nrf2). These results demonstrate that EEIH has protective effects against ALI in mice via alleviating inflammatory response, oxidative and nitrosative stress burden through activating the Nrf2 and suppressing the TLR4/NF-κB signaling pathways. The hepatoprotective activity of EEIH might be attributed to the flavonoid compounds such as catechin (1), 3',4',7-trihydroxyflavone (2), and taxifolin (7) that most possibly act synergistically.

Lactobacillus plantarum C88 protects against aflatoxin B1-induced liver injury in mice via inhibition of NF-κB-mediated inflammatory responses and excessive apoptosis

Background

Probiotics play an important role in the human and animal defense against liver damage. However, the protective mechanism of Lactobacillus plantarum C88 on chronic liver injury induced by mycotoxin remains unclear.

Results

In this study, the addition of L. plantarum C88 obviously ameliorated the increased contents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total cholesterol and triglyceride, the diminish contents of total protein and albumin in serum of mice challenged with AFB₁. Simultaneously, L. plantarum C88 attenuated the inflammatory response via significantly reducing the levels of pro-inflammatory factors, including interleukin-1β (IL-1β), IL-6, IL-8, interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in serum. Furthermore, L. plantarum C88 remarkably down-regulated the nuclear factor kappa B (NF-κB) signaling pathways by weakening the expression of toll-like receptor 2 (TLR2) and TLR4, and inhibited NF-κB nuclear translocation through enhancing the expression of NF-κB inhibitor (IκB). Neutralization experiments confirmed that L. plantarum C88 decreased the levels of some pro-inflammatory factors due to the suppression of the NF-κB signaling pathways. Besides, L. plantarum C88 decreased the levels of Bax and Caspase-3, elevated the level of Bcl-2, and reduced mRNA expressions of Fatty acid synthetase receptor (Fas), FAS-associated death domain (FADD), TNF receptor associated death domain (TRADD) and Caspase-8 in the liver.

Conclusions

Probiotic L. plantarum C88 prevented AFB₁-induced secretion of pro-inflammatory cytokines by modulating TLR2/NF-κB and TLR4/NF-κB pathways. The molecular mechanisms of L. plantarum C88 in ameliorating AFB₁-induced excessive apoptosis included regulating the mitochondrial pathway and cell death receptor pathways.

Electronic supplementary material

The online version of this article (10.1186/s12866-019-1525-4) contains supplementary material, which is available to authorized users.

Probiotic and hepatoprotective activity of lactobacillus isolated from Mongolian camel milk products

The improving-intestinal-microbial-balance properties of lactic acid bacteria (LAB) are well known. Thus, LAB could play a vital role in the pathogenesis of liver diseases. In the present study, 107 LAB strains were isolated from Mongolian camel milk products and identified to species, then screened for their probiotic properties. As a result, we identified 71 Lactobacillus bacteria belonging to 9 different species, and 36 Lactococcus bacteria belonging to 8 different species. Among them, six strains of LAB with strong tolerance and adhesion ability were further studied for their protective effect on acute liver injury induced by lipopolysaccharide (LPS)/D-galactosamine (D-GalN). These six strains of LAB were fed to mice for 7 weeks, and on the final day of the experiment, LPS/D-GalN were used to induce acute liver injury. After challenging, the degree of liver pathological changes, secretion of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and liver, and the expression of tumour necrosis factor (TNF)-α and interleukin (IL)-6 in the liver and intestines were observed and quantified. The results showed that the degree of liver pathological changes in mice fed with the six LAB strains were relieved to varying degrees compared with the LPS/D-GalN-induced model group, and the expressions of AST, ALT, IL-6, and TNF-α factor were also significantly decreased. Moreover, the expression levels of these factors in mice pretreated with Lactobacillus paracasei subsp. paracasei WXD5 were significantly decreased compared with other experimental groups. This suggests the probiotic potential and pharmacological value of L. paracasei subsp. paracasei as a liver injury inhibitor in the intervention of inflammation-based liver disease.