Inflammation: A novel target of current therapies for hepatic encephalopathy in liver cirrhosis

Preventive and therapeutic effects of rifaximin on hepatic encephalopathy with differential application dosages and strategies: a network meta-analysis

BACKGROUND

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that affects the prognosis of patients with liver disease and is considered an independent risk factor for hospitalization and death. Rifaximin has been approved for HE treatment. This review will analyze the effect of rifaximin on different stages of HE with differential application dosages and strategies by traditional and network meta-analyses.

METHODS

We performed a systematic search of PubMed, EmBase, and Cochrane Library databases up to February 26, 2023, to identify randomized controlled trials (RCTs) about rifaximin for the prevention and treatment of HE. The outcomes included incidence of HE and HE progression, HE reversal, mortality, and adverse effects.

RESULTS

A total of 21 studies were included. In the primary prevention of HE, rifaximin significantly reduced the incidence of HE (OR: 0.66; 95% CI: 0.45, 0.96; p = 0.032). In secondary prevention, rifaximin significantly reduced the risk of recurrence in patients who were in remission (OR: 0.38; 95% CI: 0.28, 0.52; p < 0.001). In the treatment of minimal HE, rifaximin significantly reduced the breakthrough of MHE to OHE (OR: 0.17; 95% CI: 0.04,0.63; p = 0.008). Rifaximin also significantly improved the clinical symptoms of MHE and OHE patients (OR: 3.76; 95% CI: 2.69, 5.25; p < 0.001). However, rifaximin did not reduce mortality at any stage in HE patients (OR: 0.79; 95% CI: 0.58, 1.08; p = 0.133). Additionally, rifaximin did not increase the risk of adverse effects (OR: 0.96; 95% CI: 0.74, 1.24; p = 0.749). In the network meta-analysis, the 400 mg T.I.D. intervention had a relative advantage for HE risks in primary and secondary prevention. In the treatment of MHE, 600 mg b.i.d. was superior in preventing the breakthrough from MHE to OHE.

CONCLUSION

Rifaximin prevented HE risks and progression and improved clinical symptoms in patients with MHE but did not reduce mortality. For primary and secondary prevention, 400 mg t.i.d. could be considered. 600 mg b.i.d. could be considered in patients with MHE.

Use of bee venom in preventive medicine: An experimental hepatic encephalopathy study in rats

OBJECTIVES

Bee venom is used for medicinal purposes, including the treatment of neurological and liver diseases, but its use as a primary health care approach for preventive purposes requires further exploration. The aim of this study was to provide the first investigation into the possible protective effects of bee venom against hepatic encephalopathy, a serious neurodegenerative disease.

MATERIALS AND METHODS

An experimental animal study was conducted in which healthy albino Sprague-Dawley rats were randomized into three groups: healthy, control and bee venom groups. All rats were tested for locomotor activity at the beginning and end of the study. No intervention was made in the healthy group, whereas hepatic encephalopathy was induced in the control and bee venom groups by the administration of thioacetamide (TAA) (200 mg/kg/day). The bee venom group also received bee venom (5 mg/kg/day) subcutaneously every day for 14 days prior to the TAA administration.

RESULTS

The results for the final locomotor activity tests were statistically better in the bee venom group than in the control group, supporting a beneficial effect of prophylactic bee venom application. Blood ammonia levels and liver weights, determined as indicators of inflammation, were lower in the bee venom group than in the control group and were close to levels in the healthy group, but not statistically significant.

CONCLUSIONS

Bee venom administration has protective effects against the development of hepatic encephalopathy and offers a promising therapeutic opportunity in preventive medicine.

TNF-α blockage by etanercept restores spatial learning and reduces cellular degeneration in the hippocampus during liver cirrhosis

Hepatic encephalopathy (HE) is one of the most debilitating cerebral complications of liver cirrhosis. The one-year survival of patients with liver cirrhosis and severe encephalopathy is less than 50%. Recent studies have indicated that neuroinflammation is a new player in the pathogenesis of HE, which seems to be involved in the development of cognitive impairment. In this study, we demonstrated neurobehavioral and neuropathological consequences of liver cirrhosis and tested the therapeutic potential of the tumor necrosis factor-α (TNF-α) inhibitor, etanercept. Sixty male adult Wistar albino rats (120-190 g) were allocated into four groups, where groups I and IV served as controls. Thioacetamide (TAA; 300 mg/kg) was intraperitoneally injected twice a week for five months to induce liver cirrhosis in group II (n = 20). Both TAA and etanercept (2 mg/kg) were administered to group III (n = 20). At the end of the experiment, spatial learning was assessed using Morris water maze. TNF-α was detected in both serum and hippocampus. The excised brains were also immunohistochemically stained with glial fibrillary acidic protein (GFAP) to estimate both the number and integrity of hippocampal astrocytes. Ultrastructural changes in the hippocampus were characterized by transmission electron microscopy. The results showed that blocking TNF-α by etanercept was accompanied by a lower TNF-α expression and a higher number of GFAP-positive astrocytes in the hippocampus. Etanercept intervention alleviated the neuronal and glial degenerative changes and impeded the deterioration of spatial learning ability. In conclusion, TNF-α is strongly involved in the development of liver cirrhosis and the associated encephalopathy. TNF-α blockers may be a promising approach for management of hepatic cirrhosis and its cerebral complications.

Clinical effects of HBV infection on patients with Rheumatoid Arthritis and Systemic Lupus Erythematosus

Objective

To investigate the clinical effects of HBV infection on patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

Methods

This is a prospective study. Thirty patients with RA and 30 patients with SLE admitted to Affiliated Hospital of Hebei University from January 2020 to December 2021 with co-infection of HBV were randomly selected and divided into two groups. Both groups were given anti-HBV treatment. An additional 60 patients with a healthy physical examination during the same period were also selected as a control group. The disease activity, immune function and serum inflammatory factor levels were compared between the RA group and the SLE group before and after treatment.

Results

After anti-HBV treatment, DAS scores in the RA group and SLEDAI scores in the SLE group were significantly lower than before treatment(P<0.05). The levels of IgG, IgA, IgM and CD8+ in the RA group and the SLE group after treatment were significantly lower than those before treatment. The levels of CCP, RF, ESR and CRP in the RA group before and after treatment were higher than those in the control group(P<0.05). The levels of ESR and CRP in the SLE group before and after treatment were higher than those in the control group, with statistically significant differences(P<0.05).

Conclusion

Patients in the RA and SLE groups after HBV infection have an increased degree of inflammatory response in their organism, an altered normal state of immunoglobulin and T-lymphocyte subsets, and a loss of organism immune function, leading to an increase in disease activity.

Anti-inflammatory strategies for hepatic encephalopathy: preclinical studies

Hepatic encephalopathy (HE) is a potentially reversible neuropsychiatric syndrome. Often, HE causes cognitive and motor dysfunctions due to an acute or chronic insufficiency of the liver or a shunting between the hepatic portal vein and systemic vasculature. Liver damage induces peripheral changes, such as in the metabolism and peripheral inflammatory responses that trigger exacerbated neuroinflammation. In experimental models, anti-inflammatory strategies have demonstrated neuroprotective effects, leading to a reduction in HE-related cognitive and motor impairments. In this scenario, a growing body of evidence has shown that peripheral and central nervous system inflammation are promising preclinical targets. In this review, we performed an overview of FDA-approved drugs and natural compounds which are used in the treatment of other neurological and nonneurological diseases that have played a neuroprotective role in experimental HE, at least in part, through anti-inflammatory mechanisms. Despite the exciting results from animal models, the available data should be critically interpreted, highlighting the importance of translating the findings for clinical essays.

Neuromodulatory role of L-arginine: nitric oxide precursor against thioacetamide-induced-hepatic encephalopathy in rats via downregulation of NF-κB-mediated apoptosis

The aim of the present study was to investigate the impact of arginine (ARG), a nitric oxide (NO) precursor, on thioacetamide (TAA)-induced hepatic encephalopathy (HE) in rats by injection of TAA (100 mg/kg, i.p) three times per week for six consecutive weeks. TAA-injected rats were administered ARG (100 mg/kg; p.o.) concurrently with TAA for the six consecutive weeks. Blood samples were withdrawn, and rats were sacrificed; liver and brain tissues were isolated. Results of the present study demonstrated that ARG administration to TAA-injected rats revealed a restoration in the serum and brain ammonia levels as well as serum aspartate transaminase, alanine transaminase, and alkaline phosphatase and total bilirubin levels as well as behavioral alterations evidenced by restoration in locomotor activity, motor skill performance, and memory impairment. ARG showed also improvement in the hepatic and neuro-biochemical values, pro-inflammatory cytokines, and oxidative stress biomarkers. All these results were confirmed by histopathological evaluation as well as ultrastructural imaging of the cerebellum using a transmission electron microscope. Furthermore, treatment with ARG could ameliorate the immunological reactivity of nuclear factor erythroid-2-related factor 2 (Nrf2) and cleaved caspase-3 proteins in the cerebellum and hepatic tissues. From all the previous results, it can be fulfilled that ARG showed a beneficial role in modulating the adverse complications associated with TAA-induced HE in rats via reducing hyperammonemia and downregulating nuclear factor kappa B (NF-κB)-mediated apoptosis.

Rifaximin Improves Liver Functional Reserve by Regulating Systemic Inflammation

Rifaximin, a non-absorbable antibiotic, has been demonstrated to be effective against hepatic encephalopathy (HE); however, its efficacy on liver functional reserve remains unknown. Here, we evaluated the efficacy of rifaximin on the liver functional reserve and serological inflammation-based markers in patients with cirrhosis. A retrospective study was conducted on patients who received rifaximin for more than three months at our hospital between November 2016 and October 2021. The recurrence and grade of HE, serological ammonia levels, Child–Pugh score (CPS), and serological inflammation-based markers such as the neutrophil–lymphocyte ratio (NLR), lymphocyte–monocyte ratio (LMR), platelet–lymphocyte ratio (PLR), C-reactive protein (CRP), and CRP to albumin ratio (CAR) were evaluated. The correlations between serological inflammation-based markers and liver functional reserve were evaluated. HE grades, serum ammonia levels, and inflammation-based markers significantly improved at three months compared with those at baseline. Patients with improved albumin levels showed significantly higher CRP improvement rates at both 3 and 12 months. Patients with an improvement in CAR at 3 months demonstrated a significant improvement in CPS at 12 months. Rifaximin improved the liver functional reserve in patients with cirrhosis. Improvements in inflammation-based markers, particularly CRP and albumin, may be involved in this process.

Psychometric tests, critical flicker frequency, and inflammatory indicators in covert hepatic encephalopathy diagnosis

Background and Aim

Hepatic encephalopathy (HE) is a frequent complication of liver diseases. Systemic inflammation is key for HE pathogenesis. The main goal of the study was to investigate the role of psychometric tests, critical flicker frequency (CFF), and comparative evaluation of inflammatory indicators for the diagnosis of covert HE (CHE).

Materials and Methods

The study was a prospective, nonrandomized, case-control study with a total of 76 cirrhotic patients and 30 healthy volunteers. The West Haven criteria were used to determine the occurrence of CHE in cirrhotic patients. Psychometric tests were applied to healthy and cirrhotic groups. CFF, venous ammonia, serum endotoxin, IL-6, IL-18, tumor necrosis factor alpha (TNF-α) levels, and hemogram parameters were evaluated for cirrhotic patients.

Results

CFF values and psychometric tests were found to accurately discriminate CHE positives from CHE negatives (p<0.05). When the control group was excluded, the digit symbol test and the number connection A test failed, unlike CFF and other psychometric tests. Using CFF, a 45 Hz cutoff value had 74% specificity and 75% sensitivity. Basal albumin levels (p=0.063), lymphocyte-to-monocyte ratio (LMR) (p=0.086), and neutrophil-to-lymphocyte ratio (p 0.052) were significant, albeit slightly, among CHE groups. Basal albumin levels had 50% sensitivity and 71% specificity when 2.8 g/dL was used as a cutoff value to determine CHE.

Conclusion

Both psychometric tests and CFF can be useful in diagnosing CHE. Using cytokine and endotoxin levels seems to be inadequate to diagnose CHE. Using LMR and albumin levels instead of psychometric tests for diagnosing CHE can be promising.

Ashwagandha-loaded nanocapsules improved the behavioral alterations, and blocked MAPK and induced Nrf2 signaling pathways in a hepatic encephalopathy rat model

Ashwagandha (ASH), a vital herb in Ayurvedic medicine, demonstrated potent preclinical hepato- and neuroprotective effects. However, its efficacy is limited due to low oral bioavailability. Accordingly, we encapsulated ASH extract in chitosan-alginate bipolymeric nanocapsules (ASH-BPNCs) to enhance its physical stability and therapeutic effectiveness in the gastrointestinal tract. ASH-BPNC was prepared by emulsification followed by sonication. The NCs showed small particle size (< 220 nm), zeta-potential of 25.2 mV, relatively high entrapment efficiency (79%), physical stability at acidic and neutral pH, and in vitro release profile that extended over 48 h. ASH-BPNC was then investigated in a thioacetamide-induced hepatic encephalopathy (HE) rat model. Compared with free ASH, ASH-BPNC improved survival, neurological score, general motor activity, and cognitive task-performance. ASH-BPNC restored ALT, AST and ammonia serum levels, and maintained hepatic and brain architecture. ASH-BPNC also restored GSH, MDA, and glutathione synthetase levels, and Nrf2 and MAPK signaling pathways in liver and brain tissues. Moreover, ASH-BPNC downregulated hepatic NF-κB immunohistochemical expression. Moreover, the in vivo biodistribution studies demonstrated that most of the administered ASH-BPNC is accumulated in the brain and hepatic tissues. In conclusion, chitosan-alginate BPNCs enhanced the hepatoprotective and neuroprotective effects of ASH, thus providing a promising therapeutic approach for HE.

Albumin therapy for hepatic encephalopathy: current evidence and controversies

Hepatic encephalopathy (HE) is a common complication that occurs in 16-21% of end-stage cirrhosis patients. Emerging evidence suggests that systemic inflammation and oxidative stress may play a role in the development of HE. Recent understanding on the anti-inflammatory properties of human albumin has led to growing interest of using human albumin for the treatment and prevention of HE among decompensated patients. In this review, we aim to discuss the current evidence and controversies of using human albumin for the treatment and prevention of HE in advanced cirrhosis patients.

Quality of life as a therapeutic objective in the management of hepatic encephalopathy and the potential role of rifaximin-α

OBJECTIVE

Quality of life (QoL) is impaired in patients with hepatic encephalopathy and rifaximin-α can improve QoL within 6 months. This study assessed the importance of QoL as a therapeutic objective in hepatic encephalopathy management; whether QoL is routinely assessed in hepatic encephalopathy patients in clinical practice and the role of rifaximin-α in this context.

METHODS

A survey was conducted of healthcare professionals (HCPs) from Europe and Australia involved in hepatic encephalopathy management. HCPs rated the importance of a range of therapeutic objectives on a 1-7 Likert scale (1 = not at all important; 7 = extremely important). HCPs were also required to provide three patient record forms (PRFs) based on their last three hepatic encephalopathy patients.

RESULTS

There were 218 HCP respondents, who provided 654 PRFs (patients treated with rifaximin-α, n = 347; patients not treated with rifaximin-α, n = 307). The mean Likert score was highest for the therapeutic objective 'improving a patient's QoL' (6.4), which was rated significantly more highly than all other therapeutic objectives, including 'reducing the patient's likelihood of hospital readmission' (6.1; P < 0.001) and 'preventing death of the patient' (6.1; P < 0.001). Despite this, only 28.3% of PRFs documented specific QoL data assessment. Patients receiving rifaximin-α were treated later in their disease course than those not receiving rifaximin-α.

CONCLUSIONS

HCPs consider QoL improvement the main therapeutic objective in hepatic encephalopathy management, but most do not explicitly assess QoL. Earlier introduction of rifaximin-α may safeguard QoL improvement even when QoL monitoring is not possible.

Effect of dihydromyricetin on hepatic encephalopathy associated with acute hepatic failure in mice

CONTEXT

Hepatic encephalopathy (HE) is a complex neuropsychiatric disease caused by liver failure. Dihydromyricetin (DMY) is a traditional medicine used to treat liver injury.

OBJECTIVE

To investigate the effects of dihydromyricetin (DMY) on hepatic encephalopathy associated with acute hepatic failure mice models established by thioacetamide (TAA) exposure.

MATERIALS AND METHODS

Female BALB/c mouse were randomly divided into control, DMY, TAA, and TAA + DMY groups (n = 8). The first two groups were intraperitoneally injected with saline or 5 mg/kg DMY, respectively. The last two groups were injected with 600 mg/kg TAA to establish HE models, and then the mice in the last group were treated with 5 mg/kg DMY. Neurological and cognition functions were evaluated 24 and 48 h after injection. Mice were sacrificed after which livers and brains were obtained for immunoblot and histopathological analysis, while blood was collected for the analysis of liver enzymes.

RESULTS

In the TAA + DMY group, ALT and AST decreased to 145.31 ± 12.88 U/L and 309.51 ± 25.92 U/L, respectively, whereas ammonia and TBIL decreased to 415.67 ± 41.91 μmol/L and 3.31 ± 0.35 μmol/L, respectively. Moreover, MDA decreased to 10.74 ± 3.97 nmol/g, while SOD and GST increased to 398.69 ± 231.30 U/g and 41.37 ± 21.84 U/g, respectively. The neurological score decreased to 2.87 ± 0.63, and the number of GFAP-positive cells decreased to 41.10 ± 1.66. Furthermore, the protein levels of TNF-α, IL-6, and GABA_A in the cortex decreased.

CONCLUSIONS

We speculate that DMY can serve as a novel treatment for HE.

Efficacy and safety of albumin infusion for overt hepatic encephalopathy: A systematic review and meta-analysis

BACKGROUND AND AIMS

The efficacy and safety of albumin infusion for treatment and prevention of overt hepatic encephalopathy (OHE) among cirrhosis patients remained controversial. We performed a systematic review and meta-analysis to evaluate the benefit of albumin infusion for the treatment and prevention of OHE.

METHODS

We performed a systematic search of 4 electronic databases up to 31st January 2021. The primary outcome was the resolution of OHE. Secondary outcomes were inpatient mortality and albumin-associated adverse events. We assessed the pooled odds' risk, pooled mean differences, 95% confidence interval and heterogeneity using Review Manager Version 5.3.

RESULTS

A total of 12 studies (2,087 subjects) were identified. Among cirrhosis patients with OHE, albumin infusion was associated with a lower pooled risk of OHE (OR=0.43, 95%CI: 0.27, 0.68; I²=0%). Among patients without baseline OHE, albumin infusion was associated with a lower pooled risk of developing OHE (OR=0.53, 95%CI: 0.32, 0.86; I²=62%). Albumin infusion was associated with a lower pooled risk of inpatient mortality (OR=0.36, 95%CI: 0.21, 0.60; I²=0%).

CONCLUSION

Well-powered randomized trials are required to confirm the benefits of albumin infusion for the prevention and treatment of overt hepatic encephalopathy among decompensated cirrhosis patients.

Intestinal Permeability Is a Mechanical Rheostat in the Pathogenesis of Liver Cirrhosis

Recent studies have suggested that an alteration in the gut microbiota and their products, particularly endotoxins derived from Gram-negative bacteria, may play a major role in the pathogenesis of liver diseases. Gut dysbiosis caused by a high-fat diet and alcohol consumption induces increased intestinal permeability, which means higher translocation of bacteria and their products and components, including endotoxins, the so-called "leaky gut". Clinical studies have found that plasma endotoxin levels are elevated in patients with chronic liver diseases, including alcoholic liver disease and nonalcoholic liver disease. A decrease in commensal nonpathogenic bacteria including Ruminococaceae and Lactobacillus and an overgrowth of pathogenic bacteria such as Bacteroidaceae and Enterobacteriaceae are observed in cirrhotic patients. The decreased diversity of the gut microbiota in cirrhotic patients before liver transplantation is also related to a higher incidence of post-transplant infections and cognitive impairment. The exposure to endotoxins activates macrophages via Toll-like receptor 4 (TLR4), leading to a greater production of proinflammatory cytokines and chemokines including tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8, which play key roles in the progression of liver diseases. TLR4 is a major receptor activated by the binding of endotoxins in macrophages, and its downstream signal induces proinflammatory cytokines. The expression of TLR4 is also observed in nonimmune cells in the liver, such as hepatic stellate cells, which play a crucial role in the progression of liver fibrosis that develops into hepatocarcinogenesis, suggesting the importance of the interaction between endotoxemia and TLR4 signaling as a target for preventing liver disease progression. In this review, we summarize the findings for the role of gut-derived endotoxemia underlying the progression of liver pathogenesis.

Cerebellar spongiform degeneration is accompanied by metabolic, cellular, and motor disruption in male rats with portacaval anastomosis

The episodes of cerebral dysfunction, known as encephalopathy, are usually coincident with liver failure. The primary metabolic marker of liver diseases is the increase in blood ammonium, which promotes neuronal damage. In the present project, we used an experimental model of hepatic encephalopathy in male rats by portacaval anastomosis (PCA) surgery. Sham rats had a false operation. After 13 weeks of surgery, the most distinctive finding was vacuolar/spongiform neurodegeneration exclusively in the molecular layer of the cerebellum. This cerebellar damage was further characterized by metabolic, histopathological, and behavioral approaches. The results were as follows: (a) Cellular alterations, namely loss of Purkinje cells, morphological changes, such as swelling of astrocytes and Bergmann glia, and activation of microglia; (b) Cytotoxic edema, shown by an increase in aquaporin-4 and N-acetylaspartate and a reduction in taurine and choline-derivate osmolytes; (c) Metabolic adjustments, noted by the elevation of circulating ammonium, enhanced presence of glutamine synthetase, and increase in glutamine and creatine/phosphocreatine; (d) Inflammasome activation, detected by the elevation of the marker NLRP3 and microglial activation; (e) Locomotor deficits in PCA rats as assessed by the Rotarod and open field tests. These results lead us to suggest that metabolic disturbances associated with PCA can generate the cerebellar damage that is similar to morphophysiological modifications observed in amyloidogenic disorders. In conclusion, we have characterized a distinctive cerebellar multi-disruption accompanied by high levels of ammonium and associated with spongiform neurodegeneration in a model of hepatic hypofunctioning.

Elevation of Autoantibodies to Cerebral Proteins in Hepatic Encephalopathy: Another Pathogenic Factor?

BACKGROUND

The pathophysiology of hepatic encephalopathy (HE) is incompletely understood. It remains elusive how the contributing factors of neuronal ammonia accumulation, cell swelling, and inflammation interact.

OBJECTIVE

The objective of this study was to find the correlation between neuronal autoantibody levels and the degree of HE as first indication of immune-mediated pathogenesis.

METHODS

We investigated serum autoantibody levels of representative brain proteins in patients with HE as well as in an experimental rat model with cirrhosis and HE after carbon tetrachloride exposure. They were examined in relation to presence of HE and the degree of neurological impairment evaluated by quantitative scores.

RESULTS

In HE, an increase in all of the examined antibodies was observed in serum. The grade of antibody elevation correlated to the degree of encephalopathy registered by quantitative evaluation of brain dysfunction.

CONCLUSION

The degree of HE parallels neuronal autoantibody elevation. In case a causal relationship could finally be established, it adds to the understanding of HE and may open a new perspective for treatment of this handicapping condition by immunosuppressive strategies.

Babao Dan improves neurocognitive function by inhibiting inflammation in clinical minimal hepatic encephalopathy

BACKGROUND AND PURPOSE

Inflammation has been considered a precipitating event that contributes to neurocognitive dysfunction in minimal hepatic encephalopathy (MHE). Inhibition TLR-4 related inflammation can effectively improve neurocognitive dysfunction of MHE. Our previous study showed that Babao Dan (BBD) effectively inhibited inflammation and ameliorated neurocognitive function in rats with acute hepatic encephalopathy (HE) and chronic HE. The mechanism may lie in the regulation of TLR4 signaling pathway. Therefore, this study aimed to evaluate the role of BBD in the treatment of MHE patients with cirrhosis and to elucidate the underlying mechanism by which BBD regulated TLR4 pathway to alleviate inflammation.

METHODS

A randomized controlled trial (n = 62) was conducted to evaluate the clinical efficacy between BBD plus lactulose (n = 31) and lactulose alone (n = 31) in MHE patients by testing neurocognitive function (NCT-A and DST), blood ammonia, liver function (ALT, AST and TBIL) and blood inflammation (IL-1β, IL-6 and TNF-α). Afterward, we detected NO, inflammatory cytokines (IL-1β, IL-6 and TNF-α) and the phosphorylation of P65, JNK, ERK as well as P38 in LPS-activated rat primary bone marrow-derived macrophages (BMDMs), peritoneal macrophages (PMs), and mouse primary BMDMs/PMs/microglia/astrocytes, to investigate the underlying mechanism of BBD inhibiting inflammation through TLR4 pathway. Also, the survival rate of mice, liver function (ALT, AST), blood inflammation (IL-1β, IL-6 and TNF-α), inflammatory cytokines (IL-1β, IL-6 and TNF-α) and histopathological changes in the liver, brain and lung were measured to assess the anti-inflammatory effect of BBD on neurocognitive function in endotoxin shock/endotoxemia mice.

RESULTS

BBD combined with lactulose significantly ameliorated neurocognitive function by decreasing NCT-A (p＜0.001) and increasing DST (p＜0.001); inhibited systemic inflammation by decreasing IL-1β (p＜0.001), IL-6(p＜0.001) and TNF-α (p＜0.001); reduced ammonia level (p = 0.005), and improved liver function by decreasing ALT(p = 0.043), AST(p = 0.003) and TBIL (p = 0.026) in MHE patients. Furthermore, BBD inhibited gene and protein expression of IL-1β, IL-6 and TNF-α as well as NO in rat primary BMDMs/PMs, and mouse primary BMDMs/PMs/microglia/astrocytes in a dose-dependent manner. BBD inhibited the activation of mouse primary BMDMs/PMs/microglia/astrocytes by regulating TLR4 pathway involving the phosphorylation of P65, JNK, ERK and P38. Also, BBD reduced the mortality of mice with endotoxin shock/endotoxemia; serum levels of ALT, AST, IL-1β, IL-6 and TNF-α; gene expression of IL-1β, IL-6 and TNF-α in the liver, brain and lung, and tissue damage in the liver and lung.

CONCLUSION

Our study provided for the first time clinical and experimental evidence supporting the use of BBD in MHE, and revealed that BBD could play a crucial role in targeting and regulating TLR4 inflammatory pathway to improve neurocognitive function in MHE patients.

New approaches to the pathogenesis, clinic, and treatment of hepatic encephalopathy

This review article presents new approaches to the assessment of key pathogenesis factors, clinical features, and treatment of hepatic encephalopathy (HE) associated with liver cirrhosis. Various clinical variants of the course of HE in patients with cirrhosis of the liver areconsidered, which are important for the choice of treatment and prevention of repeated relapses of HE. Analyzed the ammonia hypothesis of pathogenesis and associated hyperammonemia, which is the basis of most modern treatment methods. These data on the activation of the adaptive pathway for removing ammonia in the form of glutamine are used in the further study of drugs that enhance the clearance of ammonia. The possibility of reducing GABA-ergic tone due to the effect of the antagonist on the neurosteroid site in the GABA receptor complex is emphasized.

Multi-omic analysis unveils biological pathways in peripheral immune system associated to minimal hepatic encephalopathy appearance in cirrhotic patients

Patients with liver cirrhosis may develop minimal hepatic encephalopathy (MHE) which affects their quality of life and life span. It has been proposed that a shift in peripheral inflammation triggers the appearance of MHE. However, the mechanisms involved in this immune system shift remain unknown. In this work we studied the broad molecular changes involved in the induction of MHE with the goal of identifying (1) altered genes and pathways in peripheral blood cells associated to the appearance of MHE, (2) serum metabolites and cytokines with modified levels in MHE patients and (3) MHE-regulated immune response processes related to changes in specific serum molecules. We adopted a multi-omic approach to profile the transcriptome, metabolome and a panel of cytokines of blood samples taken from cirrhotic patients with or without MHE. Transcriptomic analysis supports the hypothesis of alternations in the Th1/Th2 and Th17 lymphocytes cell populations as major drivers of MHE. Cluster analysis of serum molecules resulted in six groups of chemically similar compounds, suggesting that functional modules operate during the induction of MHE. Finally, the multi-omic integrative analysis suggested a relationship between cytokines CCL20, CX3CL1, CXCL13, IL-15, IL-22 and IL-6 with alteration in chemotaxis, as well as a link between long-chain unsaturated phospholipids and the increased fatty acid transport and prostaglandin production. We found altered immune pathways that may collectively contribute to the mild cognitive impairment phenotype in MHE. Our approach is able to combine extracellular and intracellular information, opening new insights to the understanding of the disease.

The Role of Intestinal Bacteria and Gut-Brain Axis in Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a neurological disorder that occurs in patients with liver insufficiency. However, its pathogenesis has not been fully elucidated. Pharmacotherapy is the main therapeutic option for HE. It targets the pathogenesis of HE by reducing ammonia levels, improving neurotransmitter signal transduction, and modulating intestinal microbiota. Compared to healthy individuals, the intestinal microbiota of patients with liver disease is significantly different and is associated with the occurrence of HE. Moreover, intestinal microbiota is closely associated with multiple links in the pathogenesis of HE, including the theory of ammonia intoxication, bile acid circulation, GABA-ergic tone hypothesis, and neuroinflammation, which contribute to cognitive and motor disorders in patients. Restoring the homeostasis of intestinal bacteria or providing specific probiotics has significant effects on neurological disorders in HE. Therefore, this review aims at elucidating the potential microbial mechanisms and metabolic effects in the progression of HE through the gut–brain axis and its potential role as a therapeutic target in HE.

High-mobility group protein B1: A predictive biomarker for hepatic encephalopathy after transjugular intrahepatic portosystemic shunt

BACKGROUND

The aim of the present study was to investigate whether portal level of high-mobility group protein B1 (HMGB1) is associated with hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS).

METHODS

We enrolled 127 consecutive patients who underwent TIPS and collected portal and peripheral blood samples in our department from December 2017 to May 2019. HMGB1 levels were determined using enzyme-linked immunosorbent assay kits. HMGB1 and other HE related parameters were estimated by competing risk analysis, receiver operating characteristic (ROC) analysis and Kaplan-Meier analysis.

RESULTS

Patients with HE after TIPS were older (P = .019) and had higher portal HMGB1 level (P = .038) than those without. Univariate competing risk analysis: age (sHR 1.025, P = .026), hepatorenal syndrome (sHR 3.149, P = .010), model for end-of-stage liver disease (MELD) score (sHR 1.055, P = .024), prior HE (sHR 4.029, P = .0005), portal HMGB1 before TIPS (sHR 1.177, P = .001) reached statistical significance. Multivariate analysis: age (sHR 1.025, P = .037), MELD score (sHR 1.062, P = .011), prior HE (sHR 2.492, P = .030) and portal HMGB1 level before TIPS (sHR 1.217, P = .0002) were significantly different. ROC analyses and Kaplan-Meier curve showed portal HMGB1 level changes before and after TIPS (ΔHMGB1) had good predictive value in the cut-off 0.012 ng/mL (AUC = 0.748, P < .001, Sensitivity = 0.743, Specificity = 0.655).

CONCLUSIONS

Portal HMGB1 may be a therapeutic target for post-TIPS HE.

Evaluation of Preoperative and Postoperative S100β and NSE Levels in Liver Transplantation and Right Lobe Living-Donor Hepatectomy: A Prospective Cohort Study

BACKGROUND AND AIMS

This study aimed to evaluate plasma neuron-specific enolase (NSE) and S100β levels in orthotopic liver transplantation.

MATERIALS AND METHODS

A total of 56 patients who underwent orthotopic liver transplantation were divided into 3 groups. Healthy donors (group D), end-stage liver failure (ESLF) patients (recipient, group R), and ESLF patients diagnosed with hepatic encephalopathy (HE, group HE). Prognosis, preoperative routine laboratory findings, serum NSE, and S100β in samples obtained preoperation and first and sixth months postoperation were analyzed.

RESULTS

Serum NSE and S100β levels were significantly higher in ESLF patients compared to healthy donors, particularly during the preoperative period. There was a significant decrease in serum NSE and S100β in ESLF patients during the postoperative measurement periods compared to preoperative levels. Serum NSE and S100β levels measured at 3 different time points showed no significant difference between ESLF patients and ESLF patients with HE. However, the recent Model of End-Stage Liver Disease (MELD) and Child-Turcotte-Pugh (CTP) scores showed a significant correlation with serum NSE and S100β in ESLF patients diagnosed with HE. Serum NSE and S100β levels in healthy donors significantly increased within the first month following hepatectomy and decreased in the sixth month following surgery.

CONCLUSION

Although serum NSE and S100β levels significantly decreased with improved liver function in recipients following liver transplantation, there was no complete recovery within 6 months after surgery. The increase in serum levels of NSE and S100β in donors measured following hepatectomy was detected to remain slightly higher in the sixth postoperative months.

The effects of concurrent treatment of silymarin and lactulose on memory changes in cirrhotic male rats

Introduction: Chronic liver disease frequently accompanied by hepatic encephalopathy (HE). Changes in the permeability of the blood-brain barrier in HE, make an easier entrance of ammonia among other substances to the brain, which leads to neurotransmitter disturbances. Lactulose (LAC), causes better defecation and makes ammonia outreach of blood. Silymarin (SM) is a known standard drug for liver illnesses. The purpose of this research was to determine the results of LAC and SM combined treatment, on the changes in memory of cirrhotic male rats. Methods: The cirrhotic model established by treatment with thioacetamide (TAA) for 18 weeks. Cirrhotic rats randomized to four groups (n = 7): TAA group (received drinking water), LAC group (2 g/kg/d LAC in drinking water), SM group (50 mg/kg/d SM by food), SM+ LAC group (similar combined doses of both compounds) for 8 weeks. The control group received drinking water. The behavior examined by wire hanging (WH), passive avoidance (PA), and open field (OF) tests.

Results: Our findings showed that treatment with SM+LAC effectively increased PA latency, compared with the control group. The results showed that the administration of LAC and SM+LAC affected the number of lines crossed, the total distance moved and velocity in the OF tests.

Conclusion: SM and LAC have anti-inflammatory effects that are memory changing. It may be due to their useful effects. These results indicated that SM+LAC restored memory disturbance and irritated mood in the cirrhotic rats. Comparable neuroprotection was never previously informed. Such outcomes are extremely promising and indicate the further study of SM+LAC.

BabaoDan cures hepatic encephalopathy by decreasing ammonia levels and alleviating inflammation in rats

ETHNOPHARMACOLOGICAL RELEVANCE

BabaoDan (BBD) is a famous traditional Chinese formula frequently used in TCM clinics to eliminate jaundice and treat infectious viral hepatitis. This paper assesses BBD's preventive and therapeutic effects on hepatic encephalopathy after liver cirrhosis (CHE) and acute liver failure (AHE) in rats and explains its possible mechanism of action.

METHODS

CHE rat model was established by injection of carbon tetrachloride (CCl4) twice a week for a total of 9 weeks and then by injection of thioacetamide (TAA) to induce hepatic encephalopathy. AHE rat model was established by injection of TAA once a day for a total of 3 days. In CHE rat model, BBD was gavaged once a day at the end of the 6th week until the experiment ended. In AHE rat model,BBD was gavaged once a day 3 days before TAA injection until the experiment ended. The preventive and therapeutic effects of BBD on brain dysfunction, as well as liver injury, pathology and fibrosis were evaluated in vivo. The role of BBD in the regulation of inflammatory factors and myeloid differentiation factor 88/Toll-like receptor 4/nuclear factor kappa-B (TLR4/MyD88/NK-κ B) pathway was detected in both liver and brain in vivo. The rat bone marrow derived macrophages (BMDMs) were activated by Lipopolysaccharide (LPS), and the role of BBD in the regulation of inflammatory factors and NK-κ B pathway were detected in vitro.

RESULTS

In CHE rat model: BBD significantly improved the total distance as well as the activity rate of rats. BBD also improved the learning and memory abilities of rats compared with the control group. In addition, BBD effectively decreased ammonia levels and significantly decreased the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), total bilirubin (TBil) and total bile acid (TBA), as well as improved the levels of total protein (TP) and albumin (Alb). In the liver, BBD not only inhibited the gene expressions of tumor necrosis factor alpha (TNF-α), interleukini-6 (IL-6), TLR4, MyD88, and NF-κ B but also inhibited the protein expressions of TLR4, MyD88, NK-κ B and TNF-α. In the brain, BBD inhibited the gene expressions of iNOS, IL-6, TNF-α, TLR-4, MyD88, and NF-κ B, as well as inhibited the protein expressions of TLR4, MyD88, P65 TNF-α and ionized calcium binding adapter molecule 1 (Iba-1). BBD also decreased NO and TNF-α in the blood.

IN AHE RAT MODEL

BBD improved neurological scores, blood ammonia levels and the brain inflammatory gene expressions of iNOS, TNF-α and IL-1β. BBD also improved liver function biomarkers such as ALT, TBil, TBA, TP, ALB and inflammatory and apoptotic gene expressions of TNF-α, IL-1β, IL-6, Bax, Bcl-2, caspase-9, caspase-3 and NF-κ B. In LPS-activated rat BMDMs, BBD decreased NO and TNF-α production in BMDM culture supernatant. In addition, BBD inhibited the gene expressions of TNF-α, IL-1 β and IL-6 as well as the phosphorylation of P65.

CONCLUSION

BBD can prevent and cure hepatic encephalopathy (HE) derived from both chronic and acute liver diseases. BBD can reduce hyperammonemia as well as the systematic and neurological inflammation. Inflammation is likely an important target of BBD to treat HE. The anti-inflammatory role of BBD may lie in its regulation of the TLR4/MyD88/NF-κ B pathways.

Tadalafil restores long-term memory and synaptic plasticity in mice with hepatic encephalopathy

BACKGROUND AND AIM

Tadalafil displays important neuroprotective effects in experimental models of neurodegenerative diseases, however its mechanisms of action remain poorly understood. The aim of the present study was to investigate the action of Tadalafil on learning and memory, neuroinflammation, glial cell activation and neuroprotection in the experimental model of hepatic encephalopathy (HE) induced by Thioacetamide (TAA) in mice.

METHODS

Mice received intraperitoneal injections of TAA, for 3 consecutive days, reaching the final dose of 600 mg/kg. Tadalafil 15 mg/kg body weight was administered by gavage during 15 days after TAA induction. Mice underwent a Barnes maze for learning and memory evaluation.

RESULTS

Animals with hepatic encephalopathy showed reduced learning and spatial memory in the Barnes Maze, presented astrocyte and microglia activation and increased neuroinflammatory markers such as TNF-α, IL-1β, IL-6, p-p38, p-ERK and p-NF-kB. In addition, the signaling pathway PKA/PKG/CREB/BDNF/NeuN/synaptophysin and glutamate receptors were deregulated by TAA. Tadalafil treatment regulated the inflammation signaling pathways restoring learning and spatial memory.

CONCLUSION

Tadalafil significantly reduced neuroinflammation, promoted neuroprotection and plasticity, regulated the expression of hippocampal glutamate receptor and restored spatial learning ability and memory.

Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels

Lactose-based prebiotics are synthesized by enzymatic- or microbial- biotransformation of lactose and have unique functional values. In this comprehensive review article, the biochemical mechanisms of controlling osteoporosis, blood-lipid, and glucose levels by lactose-based prebiotics and symbiosis with probiotics are reported along with the results of clinical investigations. Interaction between lactose-based prebiotics and probiotics reduces osteoporosis by (a) transforming insoluble inorganic salts to soluble and increasing their absorption to gut wall; (b) maintaining and protecting mineral absorption surface in the intestine; (c) increasing the expression of calcium-binding proteins in the gut wall; (d) remodeling osteoclasts and osteoblasts formation; (e) releasing bone modulating factors; and (f) degrading mineral complexing phytic acid. Lactose-based prebiotics with probiotics control lipid level in the bloodstream and tissue by (a) suppressing the expressions of lipogenic- genes and enzymes; (b) oxidizing fatty acids in muscle, liver, and adipose tissue; (c) binding cholesterol with cell membrane of probiotics and subsequent assimilation by probiotics; (d) enzymatic-transformations of bile acids; and (e) converting cholesterol to coprostanol and its defecation. Symbiosis of lactose-based prebiotics with probiotics affect plasma glucose level by (a) increasing the synthesis of gut hormones plasma peptide-YY, glucagon-like peptide-1 and glucagon-like peptide-2 from entero-endocrine L-cells; (b) altering glucose assimilation and metabolism; (c) suppressing systematic inflammation; (d) reducing oxidative stress; and (e) producing amino acids. Clinical investigations show that lactose-based prebiotic galacto-oligosaccharide improves mineral absorption and reduces hyperlipidemia. Another lactose-based prebiotic, lactulose, improves mineral absorption, and reduces hyperlipidemia and hyperglycemia. It is expected that this review article will be of benefit to food technologists and medical practitioners.

Artificial liver support systems: what is new over the last decade?

The liver is a complex organ that performs vital functions of synthesis, heat production, detoxification and regulation; its failure carries a highly critical risk. At the end of the last century, some artificial liver devices began to develop with the aim of being used as supportive therapy until liver transplantation (bridge-to-transplant) or liver regeneration (bridge-to-recovery). The well-recognized devices are the Molecular Adsorbent Recirculating System™ (MARS™), the Single-Pass Albumin Dialysis system and the Fractionated Plasma Separation and Adsorption system (Prometheus™). In the following years, experimental works and early clinical applications were reported, and to date, many thousands of patients have already been treated with these devices. The ability of artificial liver support systems to replace the liver detoxification function, at least partially, has been proven, and the correction of various biochemical parameters has been demonstrated. However, the complex tasks of regulation and synthesis must be addressed through the use of bioartificial systems, which still face several developmental problems and very high production costs. Moreover, clinical data on improved survival are conflicting. This paper reviews the progress achieved and new data published on artificial liver support systems over the past decade and the prospects for these devices.

Role of Peripheral Inflammation in Hepatic Encephalopathy

A growing body of evidence now highlights a key role for systemic inflammation in altering behavior and mood in patients with liver disease. How inflammation occurring in the periphery in the context of liver disease, communicates with the brain to mediate changes in neurotransmission and thereby behavior is incompletely understood. Traditional routes of communication between the periphery and the brain involve neural (i.e. vagal afferent nerves) and humoral (blood-borne) pathways, with increased circulating levels of endotoxin and cytokines (especially Tumor Necrosis Factor α, TNFα) that occur during systemic inflammatory responses, as being primarily implicated in mediating signaling via these pathways. However, in recent years communication via peripheral immune-cell-to-brain and the gut-microbiota-to-brain routes have received increasing attention in the context of liver disease for their ability to modulate brain function, and generate a spectrum of symptoms ranging from fatigue and altered mood to overt Hepatic Encephalopathy (HE). In this review, we discuss periphery-to-brain communication pathways and their potential role in mediating systemic inflammation-associated alterations in behavior, that are in turn ultimately part of a spectrum of brain changes linked to the development of clinically apparent HE.

Bleeding during and after dental extractions in patients with liver cirrhosis

Little is known about the prevention and management of acquired coagulopathies, such as those affecting cirrhotic patients. The objective of this analytic retrospective observational study was to evaluate patients on the liver transplant waiting list according to the following outcomes: (1) presence of unusual intraoperative bleeding (>10min after routine haemostatic procedures); and (2) presence of postoperative haemorrhagic complications. The outcomes were analysed according to clinical and laboratory variables. A total of 190 visits were performed for extraction of 333 teeth (ranging from 1 to 9 teeth per visit), with platelet count ranging from 16,000 to 216,000 and international normalized ratio (INR) below 3. Twelve cases (6.31%) had unusual intraoperative bleeding and 12 had postoperative haemorrhagic complications. All the events were controlled by local measures. Intraoperative bleeding was associated with low count of platelets (P=0.026). However, this counting could explain only 16% (adjusted R²=0.16) of the cases of bleeding (P=0.44), meaning that platelet function changes might be involved. Our results show that cirrhotic patients presenting platelet count above 16,000 and INR below 3 need no previous blood transfusion, with local measures being enough to manage haemorrhagic events.

Biological Activities of Lactose-Derived Prebiotics and Symbiotic with Probiotics on Gastrointestinal System

Lactose-derived prebiotics provide wide ranges of gastrointestinal comforts. In this review article, the probable biochemical mechanisms through which lactose-derived prebiotics offer positive gastrointestinal health are reported along with the up-to-date results of clinical investigations; this might be the first review article of its kind, to the best of our knowledge. Lactose-derived prebiotics have unique biological and functional values, and they are confirmed as ‘safe’ by the Food and Drug Administration federal agency. Medical practitioners frequently recommend them as therapeutics as a pure form or combined with dairy-based products (yoghurt, milk and infant formulas) or fruit juices. The biological activities of lactose-derived prebiotics are expressed in the presence of gut microflora, mainly probiotics (Lactobacillus spp. in the small intestine and Bifidobacterium spp. in the large intestine). Clinical investigations reveal that galacto-oligosaccharide reduces the risks of several types of diarrhea (traveler’s diarrhea, osmotic diarrhea and Clostridium difficile associated relapsing diarrhea). Lactulose and lactosucrose prevent inflammatory bowel diseases (Crohn’s disease and ulcerative colitis). Lactulose and lactitol reduce the risk of hepatic encephalopathy. Furthermore, lactulose, galacto-oligosaccharide and lactitol prevent constipation in individuals of all ages. It is expected that the present review article will receive great attention from medical practitioners and food technologists.

Molecular Adsorbent Recirculating System as a Diagnostic and Therapeutic Modality

Despite the many advancements in liver transplantation (LT), mortality in patients with hepatic failure remains high, and to date, many patients die while awaiting LT. The molecular adsorbent recirculating system (MARS^®) is an extracorporeal liver support system intended to provide short-term metabolic detoxification, often as a vital bridge to LT. We report the case of a 41-year-old non-Hispanic White male who developed worsening multi-factorial encephalopathy in the setting of decompensated alcoholic cirrhosis. He continued to deteriorate despite supportive medical therapy, and extensive investigation for alternative causes of encephalopathy aside from hepatic was unrevealing; as a result, there was concern that his encephalopathy was due to irreversible causes from which he may not recover appropriately following LT. We herein: i) describe the implementation of MARS as a diagnostic intervention for encephalopathy of uncertain etiology in a patient with end stage liver disease who, on the basis of prompt psychomotor improvement, underwent LT 19 days post-MARS implementation with an excellent clinical outcome and thus ii) propose the use of extracorporeal liver support not only as a short-term bridge but also as a diagnostic (and potentially therapeutic) measure in cases of cryptogenic encephalopathy, particularly in the setting of advanced liver disease.

Rifaximin ameliorates hepatic encephalopathy and endotoxemia without affecting the gut microbiome diversity

AIM

To determine the efficacy of rifaximin for hepatic encephalopathy (HE) with the linkage of gut microbiome in decompensated cirrhotic patients.

METHODS

Twenty patients (12 men and 8 women; median age, 66.8 years; range, 46-81 years) with decompensated cirrhosis (Child-pugh score > 7) underwent cognitive neuropsychological testing, endotoxin analysis, and fecal microbiome assessment at baseline and after 4 wk of treatment with rifaximin 400 mg thrice a day. HE was determined by serum ammonia level and number connection test (NCT)-A. Changes in whole blood endotoxin activity (EA) was analyzed by endotoxin activity assay. Fecal microbiome was assessed by 16S ribosome RNA (rRNA) gene sequencing.

RESULTS

Treatment with rifaximin for 4 wk improved hyperammonemia (from 90.6 ± 23.9 μg/dL to 73.1 ± 33.1 μg/dL; P < 0.05) and time required for NCT (from 68.2 ± 17.4 s to 54.9 ± 20.3 s; P < 0.05) in patients who had higher levels at baseline. Endotoxin activity was reduced (from 0.43 ± 0.03 to 0.32 ± 0.09; P < 0.05) in direct correlation with decrease in serum ammonia levels (r = 0.5886, P < 0.05). No statistically significant differences were observed in the diversity estimator (Shannon diversity index) and major components of the gut microbiome between the baseline and after treatment groups (3.948 ± 0.548 at baseline vs 3.980 ± 0.968 after treatment; P = 0.544), but the relative abundances of genus Veillonella and Streptococcus were lowered.

CONCLUSION

Rifaximin significantly improved cognition and reduced endotoxin activity without significantly affecting the composition of the gut microbiome in patients with decompensated cirrhosis.

Fecal microbiota transplantation prevents hepatic encephalopathy in rats with carbon tetrachloride-induced acute hepatic dysfunction

AIM

To investigate whether fecal microbiota transplantation (FMT) prevents hepatic encephalopathy (HE) in rats with carbon tetrachloride (CCl₄)-induced acute hepatic dysfunction.

METHODS

A rat model of HE was established with CCl₄. Rat behaviors and spatial learning capability were observed, and hepatic necrosis, intestinal mucosal barrier, serum ammonia levels and intestinal permeability were determined in HE rats receiving FMT treatment. Furthermore, the expression of tight junction proteins (Claudin-1, Claudin-6 and Occludin), Toll-like receptor (TLR) 4/TLR9, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α was examined.

RESULTS

FMT improved rat behaviors, HE grade and spatial learning capability. Moreover, FMT prevented hepatic necrosis and intestinal mucosal barrier damage, leading to hepatic clearance of serum ammonia levels and reduced intestinal permeability. The expression of TLR4 and TLR9, two potent mediators of inflammatory response, was significantly downregulated in the liver of rats treated with FMT. Consistently, circulating pro-inflammatory factors such as interleukin (IL)-1β, IL-6 and tumor necrosis factor-α were remarkably decreased, indicating that FMT is able to limit systemic inflammation by decreasing the expression of TLR4 and TLR9. Importantly, HE-induced loss of tight junction proteins (Claudin-1, Claudin-6 and Occludin) was restored in intestinal tissues of rats receiving FMT treatment.

CONCLUSION

FMT enables protective effects in HE rats, and it improves the cognitive function and reduces the liver function indexes. FMT may cure HE by altering the intestinal permeability and improving the TLR response of the liver.

Gut Microbiome-based Therapeutics in Liver Cirrhosis: Basic Consideration for the Next Step

Infections account for significant morbidity and mortality in liver cirrhosis and most are related to the gut microbiome. Fecal dysbiosis, characterized by an overgrowth of potentially pathogenic bacteria and a decrease in autochthonous non-pathogenic bacteria, becomes prominent with the progression of liver cirrhosis. In cirrhotic patients, disruption of the intestinal barrier causes intestinal hyperpermeability (i.e. leaky gut), which is closely related to gut dysmotility, dysbiosis and small intestinal bacterial overgrowth and may induce pathological bacterial translocation. Although the involved microbial taxa are somewhat different between the cirrhotic patients from the East and the West, the common manifestation of a shortage of bacteria that contribute to the production of short-chain fatty acids and secondary bile acids may facilitate intestinal inflammation, leaky gut and gut dysbiosis. Translocated endotoxin and bacterial DNA are capable of provoking potent inflammation and affecting the metabolic and hemodynamic systems, which may ultimately enhance the progression of liver cirrhosis and its various complications, such as hepatic encephalopathy (HE), variceal bleeding, infection and renal disturbances. Among studies on the microbiome-based therapeutics, findings of probiotic effects on HE have been contradictory in spite of several supportive results. However, the effects of synbiotics and prebiotics are substantially documented. The background of their effectiveness should be evaluated again in relation to the cirrhosis-related changes in gut microbiome and their metabolic effects. Strict indications for the antibiotic rifaximin remain unestablished, although its effect is promising, improving HE and other complications with little influence on microbial populations. The final goal of microbiome-based therapeutics is to adjust the gut-liver axis to the maximal benefit of cirrhotic patients, with the aid of evolving metagenomic and metabolomic analyses.

Factors contributing to the development of overt encephalopathy in liver cirrhosis patients

The aim of this study was to clarify the relationships among psychometric testing results, blood ammonia (NH3) levels, electrolyte abnormalities, and degree of inflammation, and their associations with the development of overt hepatic encephalopathy (HE) in liver cirrhosis (LC) patients. The relationships between covert HE and blood NH3, sodium (Na), and C-reactive protein (CRP) were examined in 40 LC patients. The effects of elevated NH3, hyponatremia, and elevated CRP on the development of overt HE were also investigated. The covert HE group had significantly lower serum Na levels and significantly higher serum CRP levels. During the median observation period of 11 months, 10 patients developed overt HE, and the results of multivariate analysis showed that covert HE and elevated blood NH3 were factors contributing to the development of overt HE. Electrolyte abnormalities and mild inflammation are involved in the pathogenesis of HE. Abnormal psychometric testing results and hyperammonemia are linked to subsequent development of overt HE.