Minimal Hepatic Encephalopathy Patients Research Articles

EncephalApp Stroop Test as a Screening Tool for the Detection of Minimal Hepatic Encephalopathy in Patients with Cirrhosis—Single-Center Experience

Background: Minimal hepatic encephalopathy (MHE) is the mildest form of hepatic encephalopathy. One of the neuropsychological tests that detects MHE is the Stroop test (via EncephalApp). The aim was to evaluate the Stroop test for the screening and diagnosis of MHE. Methods: This prospective case–control study was performed at the Clinic for Gastroenterology and Hepatology, University Clinical Center of Serbia, and included patients with cirrhosis and MHE and healthy controls. In all patients, the presence of MHE was confirmed using the animal naming test. The Stroop test was performed on each participant, and the results were compared between the two groups. The test has two components, the “OFF” and “ON” states. Results: A total of 111 participants were included. The median OFF time did not differ between the two groups, 106.3 and 91.4, p > 0.05. However, in patients with MHE, the median values of ON time and total time were significantly higher, with 122.3 vs. 105.3 and 228.0 vs. 195.6, respectively, p < 0.05. Statistical significance between patients and controls in examined parameters was detected in younger participants and the group with higher educational levels. Conclusions: The Stroop test displayed limited sensitivity in Serbian patients. Age and education affect time measurements and test performance.

Metabolic disorder and functional disturbance in the central executive network in minimal hepatic encephalopathy.

The aim of this paper is to investigate dynamical functional disturbance in central executive network in minimal hepatic encephalopathy and determine its association with metabolic disorder and cognitive impairment. Data of magnetic resonance spectroscopy and resting-state functional magnetic resonance imaging were obtained from 27 cirrhotic patients without minimal hepatic encephalopathy, 20 minimal hepatic encephalopathy patients, and 24 healthy controls. Central executive network was identified utilizing seed-based correlation approach. Dynamic functional connectivity across central executive network was calculated using sliding-window approach. Functional states were estimated by K-means clustering. Right dorsolateral prefrontal cortex metabolite ratios (i.e. glutamate and glutamine complex/total creatine, myo-inositol / total creatine, and choline / total creatine) were determined. Neurocognitive performance was determined by psychometric hepatic encephalopathy scores. Minimal hepatic encephalopathy patients had decreased myo-inositol / total creatine and choline / total creatine and increased glutamate and glutamine complex / total creatine in right dorsolateral prefrontal cortex (all P ≤ 0.020); decreased static functional connectivity between bilateral dorsolateral prefrontal cortex and between right dorsolateral prefrontal cortex and lateral-inferior temporal cortex (P ≤ 0.001); increased frequency and mean dwell time in state-1 (P ≤ 0.001), which exhibited weakest functional connectivity. Central executive network dynamic functional indices were significantly correlated with right dorsolateral prefrontal cortex metabolic indices and psychometric hepatic encephalopathy scores. Right dorsolateral prefrontal cortex myo-inositol / total creatine and mean dwell time in state-1 yielded best potential for diagnosing minimal hepatic encephalopathy. Dynamic functional disturbance in central executive network may contribute to neurocognitive impairment and could be correlated with metabolic disorder.

Importance of 1H-MR spectroscopy of the brain to identify the minimal hepatic encephalopathy in different patients with liver cirrhosis: A prospective study.

Liver cirrhosis patients commonly progress to minimal hepatic encephalopathy (MHE) with cognitive impairment and raised blood ammonia and proinflammatory cytokines levels. This study aims to identify the subjects of MHE in patients with liver cirrhosis by hydrogen 1 magnetic resonance (1H-MR) spectroscopy of the brain, serum proinflammatory cytokines, and neuropsychiatric tests. This prospective was carried out on 100 patients of liver cirrhosis without overt hepatic encephalopathy (HE) and compared with 100 healthy controls in a tertiary care hospital in Northeast India between September 2017 and October 2019. The psychometric hepatic encephalopathy score (PHES) neuropsychological tests, cranial MRIwith 1H-MR spectroscopy, and estimation of serum interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were done. The PHES scores and serum proinflammatory markers levels were correlated with the conventional and 1H-MR spectroscopy findings of the brain. The mean PHES score in the case group was -7.58±3.43 (standard deviation [SD]) and the control group was -3.41 ± 3.87 (SD). Patients with Child-Pugh class A (n = 8) had a PHES score of -8.7 ± 2.5 (SD), class B (n = 42) -7.62 ± 3.7 (SD), and class C (n = 50) had a score of -7.36 ± 3.3 (SD). The mean value of IL-6 and TNF-α in the case group was 219 ± 180 (SD) pg/mL and 99 ± 118 (SD) pg/mL and the control group was 67.4 ± 77 (SD) pg/mL and 57.5 ± 76 (SD) pg/mL. Globus pallidus T1-weighted hyperintensities on the visibility scale with a visibility score of 0 were observed in 39 cases, a score of 1 in 38 cases, and a score of 2 in 23 cases. Increased glutamate/glutamine/creatine (Glx/Cr) ratio was identified in the case group on MR spectroscopy as compared to the control (0.95 ± 0.24 vs. 0.31 ± 0.19, P < 0.0005), a decrease of myoinositol/creatine (mI/Cr) ratio (0.11 ± 0.13 vs. 0.30 ± 0.12, P < 0.0005), and increase choline/creatine (Cho/Cr) ratio (0.69 ± 0.26 vs. 0.61 ± 0.20, P < 0.0005). There was a statistically significant difference in Glx/Cr, mI/Cr and Cho/Cr ratio between the case and control groups with P < 0.0005. Predicting the development of MHE in established cases of liver cirrhosis using non-invasive modalities like PHES, IL-6, TNF-α levels, and 1H-MR spectroscopy plays an important role in further progression to overt HE and coma.

Improved cognition after rifaximin treatment is associated with changes in intra- and inter-brain network functional connectivity

BackgroundRifaximin is a non-reabsorbable antibiotic which acts at gut level, and improves cognition and inflammatory parameters in minimal hepatic encephalopathy (MHE) patients, but not all patients show the same level of response. This study aims to assess brain activity, both within and between brain networks, following rifaximin treatment, considering the differences between response groups as well.MethodsTwenty-two healthy controls and 53 patients with cirrhosis (22 without and 31 with MHE, diagnosed by Psychometric Hepatic Encephalopathy Score, PHES) performed psychometric, attention and coordination tests, and blood inflammatory parameters were measured. Resting-state functional magnetic resonance imaging (fMRI) acquisitions were performed on controls and MHE patients. Eighteen MHE patients underwent a rifaximin treatment for 6 months, after which all measures were repeated. fMRI images were analysed and changes after treatment were assessed.ResultsAfter rifaximin treatment, 13 patients improved their PHES score (Responder patients) while 5 did not (Non-responder patients). No significant decrease in blood ammonia was observed after rifaximin treatment, but there was a decrease in plasma inflammatory cytokines in responder patients. A global effect of rifaximin was detected on the sensorimotor and fronto-parietal networks. Responder patients showed a relative increase of thalamic network connectivity in comparison to non-responder patients. Before treatment, responder and non-responder patients showed connectivity differences in basal ganglia network. The connection of the sensorimotor and thalamic networks between them and with other networks suffered changes after treatment. These connections between networks mostly decreased after treatment. All changes and differences showed a significant level of correlation with the performance of psychometric tests and the blood levels of inflammatory biomarkers.ConclusionsThere was an improvement of the communication between executive, motor and attention-related brain areas, and their functional independence following rifaximin treatment. Patients who respond also show a less deteriorated connection involved in these functions before treatment. Results suggest that the improved inflammatory state of MHE patients, following rifaximin treatment would favour the observed changes in brain function and enhanced cognitive performance.

Neurofilament Light Chain Protein in Plasma and Extracellular Vesicles Is Associated with Minimal Hepatic Encephalopathy and Responses to Rifaximin Treatment in Cirrhotic Patients.

Neurofilament light chain protein (NfL) levels reflect neuronal damage in several neurological diseases and have been proposed as a possible biomarker. Plasma extracellular vesicles (EVs) could play an important role as mediators of the inflammatory changes associated with inducing minimal hepatic encephalopathy (MHE) in cirrhotic patients. This study investigated the association of NfL levels in plasma and EVs with the presence of MHE in cirrhotic patients, and with responses to rifaximin treatment. The NfL levels in plasma and EVs were assessed in 71 patients with liver cirrhosis (40 with MHE and 31 without MHE) and 26 controls. A total of 31 patients with MHE received rifaximin treatment. We examined changes in NfL levels in plasma and EVs before and after 6 months of rifaximin treatment. The NfL measures were correlated with cognitive alterations and plasma inflammatory cytokines. MHE patients showed increased plasma levels of NfL, which were reverted after rifaximin treatment in patients who responded to treatment. The NfL content in EVs also showed a reversal pattern in MHE patients treated with rifaximin. In multivariable analyses, NfL levels were independently associated with the presence of MHE. We also showed that patients with high levels of both ammonia and fractalkine had significantly higher NfL levels than patients with low levels of least one of these parameters. Rifaximin treatment in MHE patients showed promising results in improving axonal damage, suggesting that rifaximin may have therapeutic benefits against disease progression in MHE.

White matter microstructural disruption in minimal hepatic encephalopathy: a neurite orientation dispersion and density imaging (NODDI) study.

To evaluate the ability of neurite orientation dispersion and density imaging (NODDI) for detecting white matter (WM) microstructural abnormalities in minimal hepatic encephalopathy (MHE). Diffusion-weighted images, enabling the estimation of NODDI and diffusion tensor imaging (DTI) parameters, were acquired from 20 healthy controls (HC), 22 cirrhotic patients without MHE (NHE), and 15 cirrhotic patients with MHE. Tract-based spatial statistics were used to determine differences in DTI (including fractional anisotropy [FA] and mean/axial/radial diffusivity [MD/AD/RD]) and NODDI parameters (including neurite density index [NDI], orientation dispersion index [ODI], and isotropic volume fraction [ISO]). Voxel-wise analyses of correlations between diffusion parameters and neurocognitive performance determined by Psychometric Hepatic Encephalopathy Score (PHES) were completed. MHE patients had extensive NDI reduction and rare ODI reduction, primarily involving the genu and body of corpus callosum and the bilateral frontal lobe, corona radiata, external capsule, anterior limb of internal capsule, temporal lobe, posterior thalamic radiation, and brainstem. The extent of NDI and ODI reduction expanded from NHE to MHE. In both MHE and NHE groups, the extent of NDI change was quite larger than that of FA change. No significant intergroup difference in ISO/MD/AD/RD was observed. Tissue specificity afforded by NODDI revealed the underpinning of FA reduction in MHE. The NDI in left frontal lobe was significantly correlated with PHES. MHE is characterized by diffuse WM microstructural impairment (especially neurite density reduction). NODDI can improve the detection of WM microstructural impairments in MHE and provides more precise information about MHE-related pathology than DTI.

Altered Spontaneous Brain Activity in Cirrhotic Patients with Minimal Hepatic Encephalopathy: A Meta-Analysis of Resting-State Functional Imaging.

(1) Background: Minimal hepatic encephalopathy (MHE) is an important complication of decompensated cirrhosis. Previous studies have demonstrated spontaneous brain activity alterations in cirrhotic patients with MHE. However, the reported results are inconsistent, which has limited our understanding of the potential neural mechanisms. Thus, we conducted a quantitative meta-analysis of resting-state functional imaging studies to identify the regional activity alterations consistently involved in MHE. (2) Methods: We searched six databases to include resting-state functional imaging studies and compared spontaneous brain activity patterns between MHE patients and healthy controls (HCs), and between cirrhotic patients without minimal hepatic encephalopathy (NMHE) and HCs. Then, a separate whole-brain voxel-wise meta-analysis between MHE or NMHE patients and HCs was conducted using seed-based d mapping with permutation of subject images. We further conducted the conjunction analysis to assess the distinct regional activity alterations between MHE and NMHE patients as compared to HCs. (3) Results: Thirteen studies with twenty datasets were included in this meta-analysis. Compared with HCs, MHE patients showed decreased spontaneous brain activity in the left superior frontal gyrus, left median cingulate/paracingulate gyri, and right precuneus. Compared with NMHE patients, MHE patients indicated decreased spontaneous brain activity in the left superior frontal gyrus, left median cingulate/paracingulate gyri, and right precuneus. (4) Conclusions: MHE is associated with spontaneous brain activity alterations involving the left superior frontal gyrus and median cingulate/paracingulate gyri, which may implicate primarily in spatial working memory and emotional disorders. These findings may contribute to a better understanding of the potential neural mechanisms, and guide further research.

WED-345 - Prevalence of minimal hepatic encephalopathy in patients with cirrhosis: a multicenter study

WED-345 - Prevalence of minimal hepatic encephalopathy in patients with cirrhosis: a multicenter study

Evaluation of Sleep Parameters with Polysomnography and Multiple Sleep Latency Test in Cirrhotic Patients with Daytime Sleepiness (P1-13.001)

<h3>Objective:</h3> The purpose of this study is to examine sleep parameters of cirrhosis patients who have daytime sleepiness and evaluate their correlation in terms of minimal hepatic encephalopathy (MHE). <h3>Background:</h3> Thirty cirrhosis patients were included in our study who were 18–75 years old, followed up in Marmara University Medical Faculty Hospital between December 2021–March 2022, and had Epworth sleepiness scale (ESS) ≥ 9. PSG data of 15 age-matched patients assigned as the control group, and cirrhosis patients were compared with control group. <h3>Design/Methods:</h3> Cirrhosis patients who have excessive daytime sleepiness (EDS) were classified as A and B in accordance with Child-Pugh score and they were evaluated with MSLT in the morning following one night PSG examination. At the same time, each patient was divided into 2 groups in terms of MHE by applying a PHES test battery. <h3>Results:</h3> The mean age of cases were 57,63±10,07 (min:36–max:72) years and 17 of 30 patients (56,7%) were male. It was found that 70% cryptogenic, 20% HBV, 6.7% HCV, and 3.3% was developed on the background of alcohol etiology. The mean ESS was 12,17±3,10. There was a significant decrease in N2 (p&lt;0,007) and increase in N3 stage (p&lt;0,002) in cirrhosis patients. Total sleep time (TST) and sleep efficiency (SE%) were significantly lower in cirrhosis patients than healthy population ( p&lt;0,015 and p&lt;0,030 respectively). Patients fell asleep at 2 or more naps (97%) and 48.3% had a sleep latency of 8 or less (p&lt;0.007). SOREMs were observed in 17% of the patients. <h3>Conclusions:</h3> EDS has objectively demonstrated with MSLT in our study, there was no difference in cirrhosis stages and MHE patients. It is believed that EDS may be a predictor for MHE patients and that EDS is the complaint that occurs earlier than the development of overt HE. <b>Disclosure:</b> Mr. Ismayilzada has nothing to disclose. Gulin Sunter has nothing to disclose. Kadriye Agan has nothing to disclose. Dr. Gunduz has nothing to disclose.

Comparison of the effects of probiotics, rifaximin, and lactulose in the treatment of minimal hepatic encephalopathy and gut microbiota.

Minimal hepatic encephalopathy (MHE) is an early stage in the pathogenesis of hepatic encephalopathy. Intestinal microbiota is involved in the pathogenesis of hepatic encephalopathy and has become an important therapeutic target. Since there is no unified treatment principle for MHE, this study was conducted to determine the safety and efficacy of different intestinal microecological modulators in the treatment of MHE, and to explore the potential mechanism through intestinal microbiota analysis. Patients with liver cirrhosis were screened for MHE using psychometric hepatic encephalopathy score test. Patients diagnosed with MHE were enrolled and received probiotics, rifaximin, or lactulose for 4 weeks. Adverse events were recorded. The psychometric hepatic encephalopathy score test was performed after treatment. Samples of blood and stool were collected at entry and 4 weeks. Blood samples were analyzed to assess blood ammonia, liver, kidney, and hemostatic functions. Stool microbiota were sequenced to confirm changes in microbial composition. Of 323 patients with liver cirrhosis, 74 patients were diagnosed with MHE. In all, 54 patients were enrolled and 52 who agree to follow-up were included in analysis. The recovery rates of MHE patients received probiotics, rifaximin, and lactulose were 58.8% (20/34), 45.5% (5/11), and 57.1% (4/7), respectively. Probiotics and rifaximin improved liver function in MHE patients to a certain extent. Taxonomic compositions of gut microbiota in MHE patients were distinct from healthy people before treatment; the differences were significantly reduced after treatment, and the gut microbiota gradually resembled the structure of healthy individuals. We found that the relative abundance of specific taxa associated with anti-inflammatory and good cognitive functions was increased in MHE patients after treatment. Accordingly, metabolic pathways in MHE patients were altered before and after treatment. Downregulated pathways after probiotics treatment included glycometabolism and degradation of aromatic compounds. After lactulose treatment, degradation pathways of arginine and ornithine showed a downward trend. Probiotics, rifaximin, and lactulose are safe and effective in the treatment of MHE, and improve the composition of gut microbiota to some extent.

Psychometric Hepatic Encephalopathy Score for the Diagnosis of Minimal Hepatic Encephalopathy in Thai Cirrhotic Patients.

The psychometric hepatic encephalopathy score (PHES) is the gold standard for diagnosing minimal hepatic encephalopathy (MHE). Screening for MHE is frequently overlooked in clinical practice due to time constraints. Furthermore, the simplified animal naming test (S-ANT1) is a new simple tool for evaluating MHE in cirrhotic patients. The purpose of this study was to standardize the PHES in a healthy Thai population, assess the prevalence of MHE, and validate the S-ANT1 in detecting MHE in patients with cirrhosis. The study included 194 healthy controls and 203 cirrhotic patients without overt HE. Psychometric tests and the S-ANT1 were administered to all participants. Multiple linear regression was used to analyze factors related to PHES results, and formulas were developed to predict the results for each PHES subtest. In healthy controls, age and education were predictors of all five subtests. The PHES of the control group was -0.26 ± 2.28 points, and the threshold for detecting MHE was set at ≤ -5 points. The cirrhotic group had PHES values of -2.6 ± 3.1 points. Moreover, MHE was found to be present in 26.6% of cirrhotic patients. S-ANT1 had a moderate positive correlation with PHES (r = 0.44, p &lt; 0.001). S-ANT1 &lt; 22 named animals detected MHE with a sensitivity of 71.2%, specificity of 65%, and area under the receiver operating curve of 0.68 (p &lt; 0.001). In conclusion, Thai PHES normative data have been developed to detect MHE in cirrhotic patients who do not have overt HE. The optimal cutoff for detecting MHE in Thai cirrhotic patients was PHES ≤ -5 points and S-ANT1 &lt; 22 named.

Role of gut microbiota in the pathogenesis and therapeutics of minimal hepatic encephalopathy via the gut-liver-brain axis.

Minimal hepatic encephalopathy (MHE) is a frequent neurological and psychiatric complication of liver cirrhosis. The precise pathogenesis of MHE is complicated and has yet to be fully elucidated. Studies in cirrhotic patients and experimental animals with MHE have indicated that gut microbiota dysbiosis induces systemic inflammation, hyperammonemia, and endotoxemia, subsequently leading to neuroinflammation in the brain via the gut-liver-brain axis. Related mechanisms initiated by gut microbiota dysbiosis have significant roles in MHE pathogenesis. The currently available therapeutic strategies for MHE in clinical practice, including lactulose, rifaximin, probiotics, synbiotics, and fecal microbiota transplantation, exert their effects mainly by modulating gut microbiota dysbiosis. Microbiome therapies for MHE have shown promised efficacy and safety; however, several controversies and challenges regarding their clinical use deserve to be intensively discussed. We have summarized the latest research findings concerning the roles of gut microbiota dysbiosis in the pathogenesis of MHE via the gut-liver-brain axis as well as the potential mechanisms by which microbiome therapies regulate gut microbiota dysbiosis in MHE patients.

Proportion and risk factors of Minimal Hepatic encephalopathy in patients with Child A & B cirrhosis and its response to treatment of Helicobacter pylori infection

Proportion and risk factors of Minimal Hepatic encephalopathy in patients with Child A & B cirrhosis and its response to treatment of Helicobacter pylori infection

Efficacy of probiotics in the treatment of minimal hepatic encephalopathy: A systematic review and meta-analysis.

Patients with minimal hepatic encephalopathy (MHE) have no recognizable clinical symptoms of hepatic encephalopathy (HE), but the mild cognitive and psychomotor deficits have been shown to negatively affect their daily functioning and quality of life. Treatment with probiotics has shown benefit in some clinical trials. This review aimed to systematically analyze the efficacy of probiotics in the treatment of MHE. A systematic search of the electronic databases PubMed, Science Direct, and Cochrane Library was conducted for randomized controlled trials (RCTs) in adult patients with MHE who had been given probiotics intervention. The primary outcomes were reversal of MHE and improvement of neuropsychometric tests, while the secondary outcome was the reduction of serum ammonia. Nine RCTs involving 776 MHE patients were included, consisting of 311 patients receiving probiotics and 465 patients receiving comparator (placebo or no treatment, lactulose, L-ornithine L-aspartate [LOLA], or rifaximin). The meta-analysis showed that probiotics significantly reversed MHE (OR = 3.95, p < 0.0001, 95% CI: 2.05 to 7.60) compared with placebo or no treatment. Probiotics also significantly reduced serum ammonia compared with placebo (pooled mean difference -25.94, p = 0.04, 95% CI: -50.21 to -1.66). However when compared to lactulose and LOLA, probiotics did not show a significant difference in reversal of MHE or reduction of serum ammonia levels. Probiotics were more effective in reversal of MHE and reduced serum ammonia levels in patients with MHE compared to placebo or no treatment, but not more effective than lactulose or LOLA.

Sarcopenia as a predictor of risk of minimal hepatic encephalopathy in patients with liver cirrhosis

Sarcopenia as a predictor of risk of minimal hepatic encephalopathy in patients with liver cirrhosis

Changes in early visual perception in patients with minimal hepatic encephalopathy

Minimal Hepatic Encephalopathy (MHE) is characterized by very subtle cognitive changes that are diagnosed with the Psychometric hepatic encephalopathy score (PHES) and critical flickering frequency (CFF). Patients with MHE are slower in attention tests evaluated with visual cognitive evocative potentials, which are late indicators. However, it is unknown whether there is also slowness in automatic responses of early visual perception, such as those of stationary visual potential P100. This study aimed to detect early visible changes in patients with minimal hepatic encephalopathy. Cirrhotic patients who went to the Liver Clinic of the Gastroenterology Service of the General Hospital of Mexico "Eduardo Liceaga" were included. The PHES, CFF test was applied and the electroencephalogram (EEG) was recorded while repeated visual stimuli were presented to obtain the stationary visual potential P100. The trial was approved by the research ethics committee, and informed consent was obtained. Eighty-nine patients with hepatic cirrhosis participated, 54 women (60.7%) with 53 ± 7.9 years of age and 8.3 ± 3.4 years of schooling. 57 patients (64.0%) and 64 FCP-positive (71.9%) were PHES-positive. MHE (PHES and CFF positive) was detected in 53 patients (59.6%). 29 MHE patients and 10 patients with cirrhosis agreed to do the perceptual tests. P100 latency of the visual potential was quantified lower in patients with MHD 113 ± 9 milliseconds than in cirrhotic 94 ± 14 milliseconds. Patients with MHE showed slowness in early perceptual processes that preceded cognitive processes. Donation by the volunteer ladies of the Hospital General de México “Dr. Eduardo Liceaga.” The authors declare no potential conflicts of interest.

The role of butyrylcholinesterase in the regulation of cognitive dysfunction in minimal hepatic encephalopathy: A potential blood marker of disease evolution.

Patients with cirrhosis commonly experience minimal hepatic encephalopathy (MHE), and alterations in neurotransmitters have been thought to be related to cognitive function. However, the relationship between alterations in peripheral and central butyrylcholinesterase (BuChE) with MHE disease progression remains unknown. As such, this study was designed to investigate potential changes in peripheral and central BuChE activity and their effects on cognitive function in the context of MHE. We enrolled 43 patients with cirrhosis secondary to hepatitis B, 20 without MHE and 23 with MHE, and 25 with healthy controls (HC). All the selected subjects underwent resting-state functional MRI, and the original images were processed to obtain the regional homogeneity (ReHo) brain maps. Thereafter, the correlation of BuChE activity with ReHo, number connection test of type A (NCT-A), and digital symbol test (DST) scores with MHE patients were analyzed using Person correlation analysis. Meanwhile, we purchased 12 Sprague-Dawley (SD) rats and divided them into an experimental group (n = 6) and a control group (n = 6). The rats in the experimental group were intraperitoneally injected with thioacetamide (TAA) to prepare MHE model rats. After modeling, we used the Morris water maze (MWM) and elevated plus maze (EPM) to assess the cognition function and exploratory behavior of all rats. The activity of serum, hippocampus, and frontal lobe tissue BuChE was detected by ELISA. BuChE activity gradually decreased among the HC, patients with cirrhosis, and MHE groups (all P < 0.01). We observed a linear correlation between serum BuChE and NCT-A and DST scores in MHE patients (all P < 0.01). We noted that BuChE activity can negatively correlate with ReHo values in the left middle temporal gyrus and left inferior temporal gyrus, and positively correlate with ReHo values in the right inferior frontal gyrus, and also found that the peripheral BuChE activity of MHE rats was significantly lower than their control counterparts, and the BuChE activity in frontal lobe extracts was significantly higher than the control rats (all P < 0.05). The altered activity of BuChE may contribute to cognitive impairment in MHE patients, which may be a potential biomarker of disease evolution in the context of MHE.

Plasma Extracellular Vesicles Play a Role in Immune System Modulation in Minimal Hepatic Encephalopathy.

Minimal hepatic encephalopathy (MHE) is associated with changes in the immune system including an increased pro-inflammatory environment and altered differentiation of CD4+ T lymphocytes. The mechanisms remain unknown. Changes in extracellular vesicle (EV) cargo including proteins and miRNAs could play a main role as mediators of immune system changes associated with MHE. The aim was to assess whether plasma EVs from MHE patients played a role in inducing the pro-inflammatory environment and altered differentiation of CD4+ T lymphocyte subtypes in MHE patients. We characterized the miRNA and protein cargo of plasma EVs from 50 cirrhotic patients (27 without and 23 with MHE) and 24 controls. CD4+ T cells from the controls were cultured with plasma EVs from the three groups of study, and the cytokine release and differentiation to CD4+ T-cell subtypes were assessed. Plasma EVs from MHE patients had altered miRNA and protein contents, and were enriched in inflammatory factors compared to the controls and patients without MHE. EVs from MHE patients modulated the expression of pro-inflammatory IL-17, IL-21, and TNF-α and anti-inflammatory TGF-β in cultured CD4+ T lymphocytes, and increased the proportion of Th follicular and Treg cells and the activation of Th17 cells. In conclusion, plasma EVs could play an important role in the induction of immune changes observed in MHE.

Minimal hepatic encephalopathy is associated to alterations in eye movements

Minimal hepatic encephalopathy (MHE) is diagnosed using PHES battery, but other tests are more sensitive, and a simple tool for early MHE detection is required. Assessment of saccadic eye movements is useful for early detection of cognitive alterations in different pathologies. We characterized the alterations in saccadic eye movements in MHE patients, its relationship with cognitive alterations and its utility for MHE diagnosis. One-hundred and eighteen cirrhotic patients (86 without and 32 with MHE) and 35 controls performed PHES and Stroop test and an eye movements test battery by OSCANN system: visual saccades, antisaccades, memory-guided saccades, fixation test and smooth pursuit. We analyzed 177 parameters of eye movements, assessed their diagnostic capacity for MHE, and correlated with cognitive alterations. MHE patients showed alterations in 56 of the 177 variables of eye movements compared to NMHE patients. MHE patients showed longer latencies and worse performance in most eye movements tests, which correlated with mental processing speed and attention impairments. The best correlations found were for antisaccades and memory-guided saccades, and some parameters in these tests could be useful for discriminating MHE and NMHE patients. Eye movements analysis could be a new, rapid, reliable, objective, and reproducible tool for early diagnose MHE.

Enhanced BDNF and TrkB Activation Enhance GABA Neurotransmission in Cerebellum in Hyperammonemia.

Background: Hyperammonemia is a main contributor to minimal hepatic encephalopathy (MHE) in cirrhotic patients. Hyperammonemic rats reproduce the motor incoordination of MHE patients, which is due to enhanced GABAergic neurotransmission in the cerebellum as a consequence of neuroinflammation. In hyperammonemic rats, neuroinflammation increases BDNF by activating the TNFR1–S1PR2–CCR2 pathway. (1) Identify mechanisms enhancing GABAergic neurotransmission in hyperammonemia; (2) assess the role of enhanced activation of TrkB; and (3) assess the role of the TNFR1–S1PR2–CCR2–BDNF pathway. In the cerebellum of hyperammonemic rats, increased BDNF levels enhance TrkB activation in Purkinje neurons, leading to increased GAD65, GAD67 and GABA levels. Enhanced TrkB activation also increases the membrane expression of the γ2, α2 and β3 subunits of GABAA receptors and of KCC2. Moreover, enhanced TrkB activation in activated astrocytes increases the membrane expression of GAT3 and NKCC1. These changes are reversed by blocking TrkB or the TNFR1–SP1PR2–CCL2–CCR2–BDNF–TrkB pathway. Hyperammonemia-induced neuroinflammation increases BDNF and TrkB activation, leading to increased synthesis and extracellular GABA, and the amount of GABAA receptors in the membrane and chloride gradient. These factors enhance GABAergic neurotransmission in the cerebellum. Blocking TrkB or the TNFR1–SP1PR2–CCL2–CCR2–BDNF–TrkB pathway would improve motor function in patients with hepatic encephalopathy and likely with other pathologies associated with neuroinflammation.