Sarcopenia: Ammonia metabolism and hepatic encephalopathy

The Value of Ammonia as a Biomarker in Patients with Cirrhosis

Ammonia is a product of amino acid metabolism that accumulates in the blood of patients with cirrhosis and plays a pivotal role in the pathogenesis of hepatic encephalopathy (HE). Despite being one of the main drivers of brain dysfunction, for many years international societies stated that increased blood ammonia does not add any diagnostic, staging, or prognostic value for HE in patients with cirrhosis. Nonetheless, in the last decades, evidence is emerging that supports the utility of ammonia for risk stratification, but its role in guiding HE diagnosis, staging, and treatment is unclear and there is equipoise in its use in clinical practice. This review provides the latest evidence on the value of ammonia as a biomarker in patients with cirrhosis. Although correct measurement of ammonia requires disciplined sample collection, it provides extremely useful clinical guidance for the diagnosis of HE, offers prognostic information, and it defines a therapeutic target.

The effects of Qingchang Ligan formula on hepatic encephalopathy in mouse model: results from gut microbiome-metabolomics analysis

Background

Hepatic encephalopathy (HE) is a neurological disorder resulting from advanced liver injury. HE has a high mortality rate and poor prognosis. The pathogenesis of HE is still unclear, which has led to the lack of a satisfactory specific treatment method. There is increasing evidence that the intestinal flora affects the communication between the gut and the brain in the pathogenesis of HE. Adjusting the intestinal flora has had a beneficial effect on HE in recent studies, and the Qingchang Ligan formula (QCLG) has been shown in previous studies to regulate intestinal flora and metabolites. In this study, we established a thioacetamide-induced HE mouse model to evaluate the protective effect of QCLG on HE and explore its potential mechanism, which also demonstrated that intestinal flora dysbiosis is involved in the pathogenesis of HE.

Methods

Mice were intraperitoneally injected with thioacetamide (TAA, 150 mg/kg) to induce HE. Additionally, they were orally administered Qingchang Ligan Formula (QCLG) at a dose of 6.725 g/kg·d for seven days, while control mice received an equal volume of saline via gavage. Subsequently, samples were subjected to 16S ribosomal ribonucleic acid (rRNA) gene sequencing, high-performance liquid chromatography-mass spectrometry (LC-MS), and RNA-sequencing (RNA-seq) analysis.

Result

QCLG improved weight loss, cognitive impairment, neurological function scores, blood ammonia, and brain gene expression of interleukin-6 (TNF-α), Interleukin-1β (IL-1β), and interleukin-6 (IL-6) induced by HE. Moreover, QCLG increased the levels of liver function indicators, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and serum TNF-α, IL-1β, and IL-6. 16S RNA sequencing revealed increased Oscillibacter, Colidextribacter, and Helicobacter in TAA-induced mouse fecal samples. Also, the abundance of Bifidobacterium decreases TAA-induced mouse fecal samples. In contrast, QCLG treatment significantly restored the gut microbial community. Metabolomics indicated significant differences in some metabolites among the normal control, treatment, and model groups, including 5-methoxytryptophan, Daidzein, Stercobilin, and Plumieride (PLU).

Conclusion

QCLG can alleviate neuroinflammation and prevent HE caused by liver injury by regulating intestinal flora in mouse models.

Shining a spotlight on sarcopenia and myosteatosis in liver disease and liver transplantation: Potentially modifiable risk factors with major clinical impact

Muscle-wasting and disease-related malnutrition are highly prevalent in patients with chronic liver diseases (CLD) as well as in liver transplant (LT) candidates. Alterations of body composition (BC) such as sarcopenia, myosteatosis and sarcopenic obesity and associated clinical frailty were tied to inferior clinical outcomes including hospital admissions, length of stay, complications, mortality and healthcare costs in various patient cohorts and clinical scenarios. In contrast to other inherent detrimental individual characteristics often observed in these complex patients, such as comorbidities or genetic risk, alterations of the skeletal muscle and malnutrition are considered as potentially modifiable risk factors with a major clinical impact. Even so, there is only limited high-level evidence to show how these pathologies should be addressed in the clinical setting. This review discusses the current state-of-the-art on the role of BC assessment in clinical outcomes in the setting of CLD and LT focusing mainly on sarcopenia and myosteatosis. We focus on the disease-related pathophysiology of BC alterations. Based on these, we address potential therapeutic interventions including nutritional regimens, physical activity, hormone and targeted therapies. In addition to summarizing existing knowledge, this review highlights novel trends, and future perspectives and identifies persisting challenges in addressing BC pathologies in a holistic way, aiming to improve outcomes and quality of life of patients with CLD awaiting or undergoing LT.

Sarcopenic obesity in patients awaiting liver transplant: Unique challenges for nutritional recommendations

Sarcopenic obesity increases the risk of mortality in patients with liver disease awaiting liver transplantation and in the post-transplant period. Nutrition recommendations for individuals with sarcopenia differ from recommendations for patients with obesity or sarcopenic obesity. While these nutrition guidelines have been established in non-cirrhotic patients, established guidelines for liver transplant candidates with sarcopenic obesity are lacking. In this paper, we review existing literature on sarcopenic obesity in patients with chronic liver disease and address opportunities to improve nutritional counseling in patients awaiting liver transplantation.

External validation of the modified CTP score based on ammonia to predict survival in patients with cirrhosis after TIPS placement

This study aimed to perform the first external validation of the modified Child-Turcotte-Pugh score based on plasma ammonia (aCTP) and compare it with other risk scoring systems to predict survival in patients with cirrhosis after transjugular intrahepatic portosystemic shunt (TIPS) placement. We retrospectively reviewed 473 patients from three cohorts between January 2016 and June 2022 and compared the aCTP score with the Child-Turcotte-Pugh (CTP) score, albumin-bilirubin (ALBI), model for end-stage liver disease (MELD) and sodium MELD (MELD-Na) in predicting transplant-free survival by the concordance index (C-index), area under the receiver operating characteristic curve, calibration plot, and decision curve analysis (DCA) curve. The median follow-up time was 29 months, during which a total of 62 (20.74%) patients died or underwent liver transplantation. The survival curves for the three aCTP grades differed significantly. Patients with aCTP grade C had a shorter expected lifespan than patients with aCTP grades A and B (P < 0.0001). The aCTP score showed the best discriminative performance using the C-index compared with other scores at each time point during follow-up, it also showed better calibration in the calibration plot and the lowest Brier scores, and it also showed a higher net benefit than the other scores in the DCA curve. The aCTP score outperformed the other risk scores in predicting survival after TIPS placement in patients with cirrhosis and may be useful for risk stratification and survival prediction.

Emerging drugs for the treatment of sarcopenia in cirrhosis of the liver

INTRODUCTION

Malnutrition and sarcopenia are common and impact the prognosis in patients with liver cirrhosis. The etiology is multifactorial and includes periods of reduced caloric intake, increased catabolism and direct molecular mechanisms that inhibit muscle synthesis. Although these conditions are widely acknowledged, and there is a growing interest in their diagnosis, robust evidence regarding the treatment and reversibility of these conditions is still lacking.

AREAS COVERED

We have explored the current evidence on the pharmacological treatment of sarcopenia in patients with cirrhosis. Additionally, we have searched for drugs already in use and ongoing trials for other chronic diseases.

EXPERT OPINION

The current guidelines recommend the use of a protein-adequate diet and moderate physical activity for treating sarcopenia in patients with cirrhosis. Currently, robust evidence is derived only from the supplementation of Branched-Chain Amino Acids, capable of increasing muscle mass and function. There are many drugs targeting various pathways that contribute to sarcopenia. However, evidence is sporadic and insufficient to suggest their use in clinical practice.Novel drugs specifically designed to enhance muscle mass and function should be developed. Finally, gender significantly influences the type of muscle alteration and therapeutic mechanisms; therefore, future studies should be designed taking gender differences into consideration.

Higher scores in the Clinical Frailty Scale are associated with covert and overt hepatic encephalopathy in patients with cirrhosis

BACKGROUND

Frailty increases the vulnerability to internal and external stressors and may therefore be an indicator of a higher frequency of cirrhosis complications. We aimed to investigate the association of the Clinical Frailty Scale (CFS) with covert (CHE) and overt HE (OHE) development in patients with cirrhosis.

METHODS

This study analyzed data of 228 patients with cirrhosis. Frailty was assessed using CFS. Patients were examined for the presence of CHE (using PHES) at study inclusion and followed for OHE.

RESULTS

Median CFS was 3 and 26 (11 %) patients were at least pre-frail (CFS>3). In multivariable logistic regression analysis in patients without a history of OHE (n = 195), a higher CFS was associated with the presence of CHE at baseline (OR 1.6, p = 0.039). During follow-up, 42 (18 %) patients developed an episode of OHE. In multivariable competing risk regression analyses, a higher CFS was independently associated with the development of an OHE episode in the total cohort (sHR 1.97, p < 0.001) and in the subcohort of patients without a history of OHE (sHR 1.88, p = 0.008).

CONCLUSION

CFS appears to be a reliable tool to identify patients at higher risk of HE in whom intensified monitoring and treatment may be justified.

Body Compositions Correlate With Overt Hepatic Encephalopathy after Transjugular Intrahepatic Portosystemic Shunt: A Multicentre Cohort Study

BACKGROUND

The relationship between body composition and the risk of overt hepatic encephalopathy (OHE) following transjugular intrahepatic portosystemic shunt (TIPS) needs to be investigated.

METHODS

Overall, 571 patients from 5 medical centers were included. To assess body compositions, we evaluated skeletal muscle indices, adipose tissue indices, sarcopenia, and myosteatosis at the third lumbar vertebral level. Univariate and Multivariate logistic regression analyses were performed to identify independent risk factors for post-TIPS OHE. An integrated score was then constructed using stepwise multiple regression analyses, with a cut-off value selected using the best Youden index. Finally, the Akaike information criterion (AIC) was performed to compare the integrated score and independent risk factors on their ability in predicting post-TIPS OHE.

RESULTS

Sarcopenia and all skeletal muscle indices had limited associations with post-TIPS OHE. The index of the subcutaneous adipose tissue (SATI) (P=0.005; OR: 1.034, 95% CI: 1.010-1.058) and myosteatosis (297 cases, 52.01%, 125 with OHE, 42.09%; P=0.003; OR: 1.973; 95% CI: 1.262-3.084) were both ascertained as independent risk factors for post-TIPS OHE. The integrated score (ScoreALL=1.5760 + 0.0107 * SATI + 0.8579 * myosteatosis) was established with a cutoff value of -0.935. The akaike information criterion (AIC) of ScoreALL, SATI, and myosteatosis was 655.28, 691.18, and 686.60, respectively.

CONCLUSIONS

SATI and myosteatosis are independent risk factors for post-TIPS OHE. However, the integrated score was more significantly associated with post-TIPS OHE than other skeletal muscle and adipose tissue factors.

Nutritional aspects of prehabilitation in adults with cirrhosis awaiting liver transplant

Malnutrition, sarcopenia (low muscle mass), and physical frailty have gained increasing recognition in candidates for liver transplant (LT) as these conditions can impact postoperative functional capacity. Multidimensional prehabilitation programs have been proposed as a safe intervention in adults awaiting LT but the nutritional pillar of prehabilitation has been understudied. This review summarizes the nutritional recommendations for prehabilitation for individuals with cirrhosis awaiting LT. Three major aspects of nutritional prehabilitation are discussed: (1) Assess: Evaluate nutritional status and assess for malnutrition, sarcopenia, and frailty to guide the nutritional prehabilitation intervention intensity, increasing across universal, targeted, and specialist levels; (2) Intervene: Prescribe a nutritional prehabilitation intervention to meet established nutrition guidelines in cirrhosis with a targeted focus on improving nutritional status and muscle health; (3) Reassess: Follow-up based on the required intensity of nutritional care with as needed intervention adjustment. Topics covered in the review include nutritional care levels for prehabilitation, energy prescriptions across body mass index strata, detailed considerations around protein intake (amount, distribution, and quality), carbohydrate and fat intake, other nutritional considerations, and the potential role of dietary supplements and nutraceuticals. Future research is warranted to more accurately evaluate energy needs, evaluate emerging dietary supplementation strategies, and establish the role of nutraceuticals alongside food-based interventions. While the general principles of nutritional prehabilitation are ready for immediate application, future large-scale randomized controlled trials in this space will help to quantify the benefit that can be gained by transitioning the LT approach from passive "transplant waitlist time" to active "transplant preparation time."

Implications of Protein and Sarcopenia in the Prognosis, Treatment, and Management of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a common cause of chronic liver disease globally, with prevalence rapidly increasing in parallel with rising rates of obesity and metabolic syndrome. MASLD is defined by the presence of excess fat in the liver, which may induce inflammatory changes and subsequent fibrosis in high-risk patients. Though MASLD occurs frequently, there is still no approved pharmacological treatment, and the mainstay of therapy remains lifestyle modification via dietary changes, enhancement of physical activity, and management of metabolic comorbidities. Most nutrition research and clinical guidance in this disease centers on the reduction in fructose and saturated fat in the diet, although the emerging literature suggests that protein supplementation is important and implicates muscle mass and sarcopenia in disease-related outcomes. This review will assess the current data on these topics, with the goal of defining best practices and identifying research gaps in care.

Impact of nutritional status on the outcome of transjugular intrahepatic portosystemic shunt in patients with cirrhosis: a systematic review

OBJECTIVES

Malnutrition and sarcopenia have been reported to adversely affect the outcome of patients with cirrhosis of the liver. There is an emerging body of evidence suggesting malnutrition and sarcopenia increase the risk of hepatic encephalopathy (HE) and mortality after transjugular intrahepatic portosystemic shunt (TIPS). The current systematic review aims to determine whether the body of evidence supports an association between nutritional status and post-TIPS outcomes in patients with cirrhosis.

METHODS

Electronic databases of PubMed, Embase, and Scopus were searched from inception to June 3, 2023, for studies analysing the effect of nutritional status on post-TIPS outcomes in patients with cirrhosis.

RESULTS

A total of 22 studies were included in the systemic review. Assessment of sarcopenia was done by skeletal muscle index (SMI) at the L3 level, transversal psoas muscle thickness, psoas muscle density, malnutrition as per ICD, relative sarcopenia with excess adiposity, lipid profile, controlling nutritional status score, body composition analysis, hospital frailty risk score, and visceral and subcutaneous fat area index. Ten out of 12 studies in this systematic review showed a significant association with the incidence of post-TIPS HE. Thirteen out of 14 studies reported that the presence of malnutrition was associated with increased odds of mortality following TIPS. One study reported sarcopenia as an independent predictor of liver failure, and another study reported that Pre-TIPS SMI was an independent predictor of substantial improvement in post-TIPS SMI.

CONCLUSIONS

The current systematic review shows that the presence of pre-TIPS malnutrition or sarcopenia is an independent predictor of adverse outcomes after TIPS. Incorporating these parameters into present prediction models can provide additional prognostic information.

ADVANCES IN KNOWLEDGE

Nutritional assessment should be part of the evaluation of patients planned for TIPS for prediction of adverse events after the procedure.

Association between sarcopenia and hepatic encephalopathy after transjugular intrahepatic portosystemic shunt in patients with cirrhosis: a systematic review and meta-analysis

PURPOSE

The association between the presence of sarcopenia in patients with cirrhosis and the onset of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) is yet to be established. We conducted a systematic review and meta-analysis to provide a thorough summary of the available evidence on this association.

METHODS

A thorough search of the literature was performed in the PubMed, EMBASE, and Web of Science databases. The protocol was duly registered on PROSPERO (CRD42023398856). The hazard ratio (HR) and corresponding 95% confidence intervals (CIs) for the occurrence of HE after TIPS were extracted from studies comparing cirrhotic patients with and without sarcopenia. These data were then combined using a random-effect model.

RESULTS

A total of 1135 patients from seven cohort studies that met our eligibility criteria were included in the meta-analysis. Our findings indicate a significantly higher risk of post-TIPS HE among cirrhotic patients with sarcopenia compared to those without sarcopenia (HR, 2.35; 95% CIs 1.32-4.19; p = 0.004; I2 = 75%). The findings remained consistent across subgroups stratified by liver disease etiology, study location, and severity of hepatic dysfunction.

CONCLUSION

The study demonstrated that sarcopenia was strongly linked to an increased likelihood post-TIPS HE among cirrhotic patients.

Correlation between sarcopenia and cirrhosis: a meta-analysis

Background

The relationship between sarcopenia and cirrhosis is unclear. In this research, our aim is to evaluate the prevalence of sarcopenia among individuals with liver cirrhosis and its correlation with survival and mortality risks.

Methods

We conducted searches on PubMed, Web of Science, EMBASE, and Cochrane for English articles published up to July 10, 2023, and additionally manually searched the bibliography of relevant articles. We incorporated research on sarcopenia in patients with cirrhosis to examine the connection between sarcopenia and the likelihood of survival and mortality. Statistical analyses were carried out utilizing the Stata version 15.1 software. Depending on the heterogeneity of the results, we employed either fixed-effects models or random-effects models for data synthesis. To assess publication bias, we employed funnel plots and conducted Egger's test.

Results

We included 40 studies involving 8,945 patients with cirrhosis. The overall prevalence of cirrhosis was 41% (95% CI 34%-48%). Male patients and those with liver cirrhosis and hepatic encephalopathy had a higher prevalence of sarcopenia (44% for male patients and 48% for hepatic encephalopathy patients). Sarcopenia emerged as a risk factor for both survival (HR = 2.57, 95% CI 2.02-3.27, p < 0.001) and mortality (HR = 2.13, 95% CI 1.86-2.44, p < 0.001) in patients with cirrhosis. Subgroup analyses consistently yielded the same results for study sites, whether HCC patients were excluded from the cohort, whether patients were from the liver transplant cohort or had undergone tips surgery, the definition of sarcopenia (L3-SMI or other methods), and the diagnostic criteria used by patients. The presence of sarcopenia was also a significant risk factor for hepatic encephalopathy [HR = 2.27, 95% CI (1.76-2.94), p < 0.001].

Conclusion

This systematic review and meta-analysis reveal that patients with cirrhosis have a prevalence of sarcopenia of 41% and is associated with survival rate and mortality rate. Therefore, we should attach importance to the screening of sarcopenia in patients with cirrhosis, early detection of susceptible populations, and appropriate measures to reduce the occurrence and adverse outcomes.Systematic review registration:https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

Portal Hypertension in Malnutrition and Sarcopenia in Decompensated Cirrhosis-Pathogenesis, Implications and Therapeutic Opportunities

Malnutrition and sarcopenia are highly prevalent in patients with decompensated cirrhosis and are associated with poorer clinical outcomes. Their pathophysiology is complex and multifactorial, with protein-calorie malnutrition, systemic inflammation, reduced glycogen stores and hormonal imbalances all well reported. The direct contribution of portal hypertension to these driving factors is however not widely documented in the literature. This review details the specific mechanisms by which portal hypertension directly contributes to the development of malnutrition and sarcopenia in cirrhosis. We summarise the existing literature describing treatment strategies that specifically aim to reduce portal pressures and their impact on nutritional and muscle outcomes, which is particularly relevant to those with end-stage disease awaiting liver transplantation.

A Prospective Study of Prevalence and Impact of Sarcopenia on Short-term Mortality in Hospitalized Patients with Liver Cirrhosis

Background

Sarcopenia is common in chronic advanced liver disease and is associated with poor prognosis. There is paucity of Indian data regarding sarcopenia in chronic advanced liver disease & its impact on prognosis. The aim of this study was to study the prevalence of sarcopenia in Indian patients with chronic advanced liver disease and its impact on morbidity and short-term mortality.

Methods

Patients with chronic advanced liver disease were prospectively evaluated for the presence of sarcopenia using computerized tomography (CT) abdomen. The cross-sectional area of the right psoas muscle was measured at the third lumbar vertebra (L3) and the Psoas muscle index (PMI) was calculated. Sarcopenia was defined as PMI <295 mm2/m2 for females and <356 mm2/m2 for males. The normative values of PMI were obtained from patients undergoing CT scan for non-specific abdominal pain who had no confounding factor which could result in sarcopenia. All patients were followed up for 6 months or until death, whichever was earlier. The impact of sarcopenia on mortality and rate of readmission has been assessed at the end of 6 months.

Results

Of the 156 patients with chronic advanced liver disease, 74 (47.4%) patients had sarcopenia. Sarcopenia was more commonly seen in males (M: F = 61:13) and in patients with alcohol-related liver disease. There was a linear correlation (negative) between the PMI and severity of liver disease as assessed by Child-Pugh and model for end-stage liver disease (MELD) scores (r = -0.591 and -0.465, respectively). Patients with encephalopathy, ascites, and coagulopathy had higher prevalence of sarcopenia. On six months follow-up, sarcopenic patients had higher readmission rates (74.3% vs. 22%; P = 0.0001) and higher mortality (24.3% vs. 3.7%; P = 0.002). MELD score and PMI were independent predictors of mortality. The cut-off value of PMI 305.9 mm2/m2 predicted mortality with a sensitivity of 76.2% and a false positivity of 22.2% (area under curve was 0.805; 95% confidence interval: 0.69-0.91, P = 0.001).

Conclusion

Sarcopenia is seen in about half of the patients with chronic advanced liver disease. It is commoner in males, patients with alcoholic liver disease, and those with advanced liver disease. Patients with sarcopenia have worse prognosis, require more frequent hospitalization and it negatively impacts short-term survival.

Pretransplant Functional Status Predicts Postoperative Morbidity and Mortality after Liver Transplantation in Patients with Cirrhosis

Background/Aims

This study aimed to investigate whether pretransplant frailty can predict postoperative morbidity and mortality after liver transplantation (LT) in patients with cirrhosis.

Methods

We retrospectively reviewed 242 patients who underwent LT between 2018 and 2020 at a tertiary hospital in Korea.

Results

Among them, 189 patients (78.1%) received LT from a living donor. Physical frailty at baseline was assessed by the Short Physical Performance Battery (SPPB), by which patients were categorized into two groups: frail (SPPB <10) and non-frail (SPPB ≥10). Among the whole cohort (age, 55.0±9.2 years; male, 165 [68.2%]), 182 patients were classified as non-frail and 60 patients were classified as frail. Posttransplant survival was shorter in the frail group than the non-frail group (9.3 months vs 11.6 months). Postoperative intensive care unit stay was longer in the frail group than in the non-frail group (median, 6 days vs 4 days), and the 30-day complication rate was higher in the frail group than in the non-frail group (78.3% vs 59.3%). Frailty was an independent risk factor for posttransplant mortality (adjusted hazard ratio, 2.38; 95% confidence interval, 1.02 to 5.57). In subgroup analysis, frail patients showed lower posttransplant survival regardless of history of hepatocellular carcinoma and donor type.

Conclusions

Assessment of pretransplant frailty, as measured by SPPB, provides important prognostic information for clinical outcomes in cirrhotic patients undergoing LT.

Investigation of Changes in Skeletal Muscle Mass and Muscle Quality and Factors Affecting Changes in Deceased Donor Liver Transplantation

BACKGROUND

In Japan, there are very few cases of deceased donor liver transplantation (DDLT) and even fewer studies on the effects of DDLT on sarcopenia. This study examined the changes in skeletal muscle mass and quality in DDLT, the factors related to these changes, and survival rates.

METHODS

Using computed tomography (CT), we retrospectively measured L3 skeletal muscle index (L3SMI) and intramuscular adipose tissue content (IMAC) at admission, discharge, and 1-year post-DDLT in 23 patients with DDLT from our hospital between 2011 and 2020. We investigated the relationships between changes in L3SMI and IMAC associated with DDLT and between various admission factors and survival.

RESULTS

Patients with DDLT showed significant decreases in L3SMI during hospitalization (P < .05). Although L3SMI tended to increase postdischarge, in 11 (73%) cases, it was lower at 1-year post-DDLT than that on admission. Moreover, decreases in L3SMI during hospitalization were correlated to L3SMI on admission (r = 0.475, P < 0.05). Intramuscular adipose tissue content increased from admission to discharge and decreased 1-year post-DDLT. Admission L3SMI and IMAC were not significantly correlated with survival.

CONCLUSIONS

This study suggests that the skeletal muscle mass of DDLT patients decreased during hospitalization and showed a slight tendency to improve after discharge, but the decrease tended to be prolonged. In addition, patients with higher skeletal muscle mass at admission tended to lose more skeletal muscle mass during hospitalization. Deceased donor liver transplantation was identified as a potential contributor to improved muscle quality, whereas skeletal muscle mass and quality on admission did not affect post-DDLT survival.

Sarcopenia in cirrhosis: Prospects for therapy targeted to gut microbiota

Decreased muscle mass and function, also known as sarcopenia, is common in patients with cirrhosis and is associated with a poor prognosis. Although the pathogenesis of this disorder has not been fully elucidated, a disordered gut-muscle axis probably plays an important role. Decreased barrier function of the gut and liver, gut dysbiosis, and small intestinal bacterial overgrowth (SIBO) can lead to increased blood levels of ammonia, lipopolysaccharides, pro-inflammatory mediators, and myostatin. These factors have complex negative effects on muscle mass and function. Drug interventions that target the gut microbiota (long-term use of rifaximin, lactulose, lactitol, or probiotics) positively affect most links of the compromised gut-muscle axis in patients with cirrhosis by decreasing the levels of hyperammonemia, bacterial translocation, and systemic inflammation and correcting gut dysbiosis and SIBO. However, although these drugs are promising, they have not yet been investigated in randomized controlled trials specifically for the treatment and prevention of sarcopenia in patients with cirrhosis. No data exist on the effects of fecal transplantation on most links of gut-muscle axis in cirrhosis; however, the results of animal experimental studies are promising.

GDF8 Contributes to Liver Fibrogenesis and Concomitant Skeletal Muscle Wasting

Patients with end-stage liver disease exhibit progressive skeletal muscle atrophy, highlighting a negative crosstalk between the injured liver and muscle. Our study was to determine whether TGFβ ligands function as the mediators. Acute or chronic liver injury was induced by a single or repeated administration of carbon tetrachloride. Skeletal muscle injury and repair was induced by intramuscular injection of cardiotoxin. Activin type IIB receptor (ActRIIB) ligands and growth differentiation factor 8 (Gdf8) were neutralized with ActRIIB-Fc fusion protein and a Gdf8-specific antibody, respectively. We found that acute hepatic injury induced rapid and adverse responses in muscle, which was blunted by neutralizing ActRIIB ligands. Chronic liver injury caused muscle atrophy and repair defects, which were prevented or reversed by inactivating ActRIIB ligands. Furthermore, we found that pericentral hepatocytes produce excessive Gdf8 in injured mouse liver and cirrhotic human liver. Specific inactivation of Gdf8 prevented liver injury-induced muscle atrophy, similar to neutralization of ActRIIB ligands. Inhibition of Gdf8 also reversed muscle atrophy in a treatment paradigm following chronic liver injury. Direct injection of exogenous Gdf8 protein into muscle along with acute focal muscle injury recapitulated similar dysregulated muscle regeneration as that observed with liver injury. The results indicate that injured liver negatively communicate with the muscle largely via Gdf8. Unexpectedly, inactivation of Gdf8 simultaneously ameliorated liver fibrosis in mice following chronic liver injury. In vitro, Gdf8 induced human hepatic stellate (LX-2) cells to form a septa-like structure and stimulated expression of profibrotic factors. Our findings identified Gdf8 as a novel hepatomyokine contributing to injured liver-muscle negative crosstalk along with liver injury progression.

Sarcopenia in chronic viral hepatitis: From concept to clinical relevance

Although the frequency of metabolic risk factors for cirrhosis and hepatocellular carcinoma (HCC) is increasing, chronic hepatitis B (CHB) and chronic hepatitis C (CHC) remain the most relevant risk factors for advanced liver disease worldwide. In addition to liver damage, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are associated with a myriad of extrahepatic manifestations including mixed cryoglobulinaemia, lymphoproliferative disorders, renal disease, insulin resistance, type 2 diabetes, sicca syndrome, rheumatoid arthritis-like polyarthritis, and autoantibody production. Recently, the list has grown to include sarcopenia. Loss of muscle mass or muscle function is a critical feature of malnutrition in cirrhotic patients and has been found in approximately 23.0%-60.0% of patients with advanced liver disease. Nonetheless, among published studies, there is significant heterogeneity in the aetiologies of hepatic diseases and measurement methods used to determine sarcopenia. In particular, the interaction between sarcopenia, CHB and CHC has not been completely clarified in a real-world setting. Sarcopenia can result from a complex and multifaceted virus-host-environment interplay in individuals chronically infected with HBV or HCV. Thus, in the present review, we provide an overview of the concept, prevalence, clinical relevance, and potential mechanisms of sarcopenia in patients with chronic viral hepatitis, with an emphasis on clinical outcomes, which have been associated with skeletal muscle loss in these patients. A comprehensive overview of sarcopenia in individuals chronically infected with HBV or HCV, independent of the stage of the liver disease, will reinforce the necessity of an integrated medical/nutritional/physical education approach in the daily clinical care of patients with CHB and CHC.

Potential Benefits of Epidermal Growth Factor for Inhibiting Muscle Degrative Markers in Rats with Alcoholic Liver Damage

This study investigated the beneficial effects of epidermal growth factor (EGF) on muscle loss in rats with chronic ethanol feeding. Six-week-old male Wistar rats were fed either a control liquid diet without EGF (C group, n = 12) or EGF (EGF-C group, n = 18) for two weeks. From the 3rd to 8th week, the C group was divided into two groups. One was continually fed with a control liquid diet (C group), and the other one was fed with an ethanol-containing liquid diet (E group); moreover, the EGF-C group was divided into three groups, such as the AEGF-C (continually fed with the same diet), PEGF-E (fed with the ethanol-containing liquid diet without EGF), and AEGF-E (fed with the ethanol-containing liquid diet with EGF). As a result, the E group had significantly higher plasma ALT and AST, endotoxin, ammonia, and interleukin 1b (IL-1b) levels, along with liver injuries, such as hepatic fatty changes and inflammatory cell infiltration. However, plasma endotoxin and IL-1b levels were significantly decreased in the PEGF-E and AEGF-E groups. In addition, the protein level of muscular myostatin and the mRNA levels of forkhead box transcription factors (FOXO), muscle RING-finger protein-1 (MURF-1) and atorgin-1 was increased considerably in the E group but inhibited in the PEGF-E and AEGF-E groups. According to the principal coordinate analysis findings, the gut microbiota composition differed between the control and ethanol liquid diet groups. In conclusion, although there was no noticeable improvement in muscle loss, EGF supplementation inhibited muscular protein degradation in rats fed with an ethanol-containing liquid diet for six weeks. The mechanisms might be related to endotoxin translocation inhibition, microbiota composition alteration as well as the amelioration of liver injury. However, the reproducibility of the results must be confirmed in future studies.

Prediction and prevention of the first episode of overt hepatic encephalopathy in patients with cirrhosis

Hepatic encephalopathy (HE) is one of the most important complications of patients with liver cirrhosis. In addition, HE is associated with a dismal prognosis and has detrimental effects on patients' quality of life. Thus, it is of pivotal importance to identify patients at high risk for overt HE (OHE) in whom primary prophylaxis may be justified. In this narrative review, we aim to provide insight into predictors and prediction tools for a first-time episode of OHE and to scrutinize the current level of evidence of primary prophylaxis. In recent decades, several cognitive tests, composite scores, and blood-based biomarkers have been demonstrated to be predictive of a first-time episode of OHE. Among the best validated are the established tests for minimal HE, such as the Psychometric Hepatic Encephalopathy Score, determination of the critical flicker frequency, Stroop EncephalApp, or the Animal Naming Test. Individualized risk stratification using blood-based biomarkers and cross-sectional imaging (sarcopenia and spontaneous portosystemic shunts) is coming to the fore, but validation in larger multicenter cohorts is often lacking. On the basis of current evidence, a recommendation for primary prophylaxis of a first episode of OHE cannot be made in general. Only 2 studies have investigated the prevention of a first-time OHE episode as the primary endpoint. In this narrative review, we provide a concise overview of the current evidence levels on prediction tools and pharmacological prevention of a first episode of OHE. In addition, we give an outlook on future research targets to improve knowledge on this important topic.

Current vision on diagnosis and comprehensive care in hepatic encephalopathy

The first clinical guidelines on hepatic encephalopathy were published in 2009. Almost 14 years since that first publication, numerous advances in the field of diagnosis, treatment, and special condition care have been made. Therefore, as an initiative of the Asociación Mexicana de Gastroenterología A.C., we present a current view of those aspects. The manuscript described herein was formulated by 24 experts that participated in six working groups, analyzing, discussing, and summarizing the following topics: Definition of hepatic encephalopathy; recommended classifications; epidemiologic panorama, worldwide and in Mexico; diagnostic tools; conditions that merit a differential diagnosis; treatment; and primary and secondary prophylaxis. Likewise, these guidelines emphasize the management of certain special conditions, such as hepatic encephalopathy in acute liver failure and acute-on-chronic liver failure, as well as specific care in patients with hepatic encephalopathy, such as the use of medications and types of sedation, describing those that are permitted or recommended, and those that are not.

Enteral nutrition product formulations: A review of available products and indications for use

When oral nutrition is not feasible, enteral nutrition (EN) therapy is often considered the preferred route of nutrition support to meet the nutrient needs of individuals with a functional gastrointestinal tract across multiple levels of care (critical care, acute care, and home care). Enteral formulations have progressively evolved over the last 50 years from the simple blending of hospital food thin enough to run through a feeding tube, to the development of commercial standard formulas, followed by specialized formulas with immune-modulating and disease-specific qualities, to the most recent shift to food-based or blenderized EN composed of natural, whole foods with perceived health benefits. With the vast number of enteral formulations on the market, clinicians may be overwhelmed trying to determine proven vs theoretical benefits. This review is intended to explore differences in enteral formulations, identify implications for clinical practice, and review evidenced-based clinical guidelines to assist clinicians in enteral formula selection.

Methionine adenosyltransferase2A inhibition restores metabolism to improve regenerative capacity and strength of aged skeletal muscle

We investigate the age-related metabolic changes that occur in aged and rejuvenated myoblasts using in vitro and in vivo models of aging. Metabolic and signaling experiments reveal that human senescent myoblasts and myoblasts from a mouse model of premature aging suffer from impaired glycolysis, insulin resistance, and generate Adenosine triphosphate by catabolizing methionine via a methionine adenosyl-transferase 2A-dependant mechanism, producing significant levels of ammonium that may further contribute to cellular senescence. Expression of the pluripotency factor NANOG downregulates methionine adenosyltransferase 2 A, decreases ammonium, restores insulin sensitivity, increases glucose uptake, and enhances muscle regeneration post-injury. Similarly, selective inhibition of methionine adenosyltransferase 2 A activates Akt2 signaling, repairs pyruvate kinase, restores glycolysis, and enhances regeneration, which leads to significant enhancement of muscle strength in a mouse model of premature aging. Collectively, our investigation indicates that inhibiting methionine metabolism may restore age-associated impairments with significant gain in muscle function.

Breath-by-breath measurement of exhaled ammonia by acetone-modifier positive photoionization ion mobility spectrometry via online dilution and purging sampling

Exhaled ammonia (NH₃) is an essential noninvasive biomarker for disease diagnosis. In this study, an acetone-modifier positive photoionization ion mobility spectrometry (AM-PIMS) method was developed for accurate qualitative and quantitative analysis of exhaled NH₃ with high selectivity and sensitivity. Acetone was introduced into the drift tube along with the drift gas as a modifier, and the characteristic NH₃ product ion peak of (C₃H₆O)₄NH₄⁺ (K₀ = 1.45 cm²/V·s) was obtained through the ion-molecule reaction with acetone reactant ions (C₃H₆O)₂H⁺ (K₀ = 1.87 cm²/V·s), which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH₃ qualitative identification. Moreover, the interference of high humidity and the memory effect of NH₃ molecules were significantly reduced via online dilution and purging sampling, thus realizing breath-by-breath measurement. As a result, a wide quantitative range of 5.87-140.92 μmol/L with a response time of 40 ms was achieved, and the exhaled NH₃ profile could be synchronized with the concentration curve of exhaled CO₂. Finally, the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH₃ of healthy subjects, demonstrating its great potential for clinical disease diagnosis.

Sarcopenia and Frailty in Cirrhosis

Sarcopenia and frailty are frequent in cirrhosis, and both contribute to increased morbidity and mortality. The complex pathogenesis of sarcopenia in cirrhosis is mainly determined by hyperammonemia and malnutrition. Sarcopenia/frailty screening and reevaluation should be undertaken in all cirrhotic patients. Frailty tests are useful in the ambulatory setting, whereas the computed tomography scan is the diagnostic gold standard for sarcopenia. To manage sarcopenia/frailty, a multidisciplinary team should develop a personalized comprehensive care plan that includes patient education, protein/calorie intake goals, late evening meals, exercise programs, and micronutrient replenishment. In selected patients, branched-chain amino acid and testosterone supplements may also be beneficial.

Upregulation of CCL5/RANTES Gene Expression in the Diaphragm of Mice with Cholestatic Liver Disease

Chronic liver diseases are a group of pathologies affecting the liver with high prevalence worldwide. Among them, cholestatic chronic liver diseases (CCLD) are characterized by alterations in liver function and increased plasma bile acids. Secondary to liver disease, under cholestasis, is developed sarcopenia, a skeletal muscle dysfunction with decreased muscle mass, strength, and physical function. CCL5/RANTES is a chemokine involved in the immune and inflammatory response. Indeed, CCL5 is a myokine because it is produced by skeletal muscle. Several studies show that bile acids induce CCL5/RANTES expression in liver cells. However, it is unknown if the expression of CCL5/RANTES is changed in the skeletal muscle of mice with cholestatic liver disease. We used a murine model of cholestasis-induced sarcopenia by intake of hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC diet), in which we detected the mRNA levels for ccl5. We determined that mice fed the DDC diet presented high levels of serum bile acids and developed typical features of sarcopenia. Under these conditions, we detected the ccl5 gene expression in diaphragm muscle showing elevated mRNA levels compared to mice fed with a standard diet (chow diet). Our results collectively suggest an increased ccl5 gene expression in the diaphragm muscle concomitantly with elevated serum bile acids and the development of sarcopenia.

Sarcopenia in the Cirrhotic Patient: Current Knowledge and Future Directions

Cirrhosis predisposes to abnormalities in energy, hormonal, and immunological homeostasis. Disturbances in these metabolic processes create susceptibility to sarcopenia or pathological muscle wasting. Sarcopenia is prevalent in cirrhosis and its presence portends significant adverse outcomes including the length of hospital stay, infectious complications, and mortality. This highlights the importance of identification of at-risk individuals with early nutritional, therapeutic and physical therapy intervention. This manuscript summarizes literature relevant to sarcopenia in cirrhosis, describes current knowledge, and elucidates possible future directions.

Skeletal muscle mass index as a predictor of long-term cirrhosis onset in young non-cirrhotic males with acute-on-chronic liver failure

Background

The relationship between skeletal muscle mass index (SMI) and cirrhosis incidence in patients with non-cirrhotic acute-on-chronic (ACLF) has not been clarified. This study aimed to assess the predictive value of SMI on the incidence of long-term cirrhosis in male non-cirrhotic ACLF patients.

Materials and methods

Male ACLF patients who were free of liver cirrhosis were retrospectively included in this study. Univariate and multivariate logistic analyses were conducted to determine the risk factors for the long-term (1-year) development of cirrhosis. The receiver operating characteristic curves (ROC) were used to assess the ability of SMI levels to predict the incidence of cirrhosis. Restricted triple spline (RCS) described the dose-response relationship between SMI and the risk of cirrhosis. Subgroup analysis was stratified by age (≤ 40 years and > 40 years).

Results

A total of 230 subjects were included in this study, of whom 45.2% (104/230) were diagnosed with cirrhosis within 360 days. Patients who progressed to cirrhosis had a lower SMI [46.1 ± 6.9 versus 49.2 ± 6.5 cm²/m², P = 0.001] and a higher proportion of sarcopenia (19.2% versus 6.3%, P = 0.003). In multivariate logistic regression, SMI remained a protective agent against 360-days progression to cirrhosis in males with ACLF after adjustment (OR 0.950, 95% CI: 0.908-0.994, P < 0.05). SMI exerted a non-linear dose-dependent effect on the risk of cirrhosis. The area under the ROC curve (AUC) for the L3-SMI to predict the incidence of cirrhosis in male non-cirrhotic ACLF patients was 0.636 (P < 0.001). We observed significant differences in SMI among male ACLF patients in different age groups. Further subgroup analysis by age revealed that lower SMI was associated with the 1-year incidence of cirrhosis in male ACLF patients aged less than 40 years (OR 0.908, 95% CI: 0.842-0.979, P < 0.05), whereas SMI did not affect the 1-year risk of cirrhosis in older subjects (age > 40 years).

Conclusion

A higher SMI represents an independent protective factor for developing long-term cirrhosis in male ACLF patients who do not experience cirrhosis, especially in those under 40 years of age.

The sex-specific prognostic utility of sarcopenia in cirrhosis

Sarcopenia is an increasingly recognized complication of cirrhosis that is associated with morbidity and mortality. Differences in the prevalence and prognosis of sarcopenia between men and women have been reported in other patient groups, but there is insufficient understanding of how sex impacts the prognostic value of sarcopenia in cirrhosis. A search of MEDLINE and Embase was conducted from earliest entries to April 2021. Studies were included if they examined sex-stratified mortality impact of reduced muscle function or mass in outpatient populations with cirrhosis. We identified 700 studies of which 6 were deemed relevant for inclusion in this narrative review. Studies of interest were heterogeneous, precluding pooling of data and making interpretation of the literature challenging. Muscle mass was assessed in five studies (n = 2566, 1730 men, 836 women) and was reduced in 36-50% of men and 24-43% of women. All five studies found that reduced muscle mass determined by computed tomography, dual-energy X-ray absorptiometry, and bioelectrical impedance analysis was associated with increased mortality in men. Of these, two studies identified a corresponding relationship in women; reduced muscle mass defined by computed tomography was associated with increased mortality [hazard ratio (HR) 2.82, P = 0.001], while increasing muscle mass by bioelectrical impedance analysis likewise conferred a survival benefit (HR 0.45, P = 0.0016). Only one study assessed the relationship of muscle function with sex-stratified mortality (n = 1405, 827 men, 578 women), concluding that reduced muscle function predicted mortality in both men and women (HR 1.65, P < 0.001 and HR 1.54, P < 0.001, respectively). Reduced muscle mass in cirrhosis is consistently associated with mortality in men, but lack of sex-stratification of mortality analyses limits the ability to make strong conclusions about the impact of sarcopenia specifically in women, with even fewer data available for analysing muscle function. Improved understanding of the sex-specific impacts of sarcopenia may help address patient deterioration and mortality while awaiting liver transplantation and allow for early intervention to mitigate mortality risk. Large, multicentre studies with adequate female participation and sex-stratified mortality analyses are warranted.

Impact of L-ornithine L-aspartate on non-alcoholic steatohepatitis-associated hyperammonemia and muscle alterations

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common chronic liver disease in the world. Progression toward non-alcoholic steatohepatitis (NASH) is associated with alterations of skeletal muscle. One plausible mechanism for altered muscle compartment in liver disease is changes in ammonia metabolism. In the present study, we explored the hypothesis that NASH-associated hyperammonemia drives muscle changes as well as liver disease progression.

MATERIALS AND METHODS

In Alms1-mutant mice (foz/foz) fed a 60% fat diet (HFD) for 12 weeks; we investigated hepatic and muscular ammonia detoxification efficiency. We then tested the effect of an 8 week-long supplementation with L-ornithine L-aspartate (LOLA), a known ammonia-lowering treatment, given after either 4 or 12 weeks of HFD for a preventive or a curative intervention, respectively. We monitored body composition, liver and muscle state by micro computed tomography (micro-CT) as well as muscle strength by four-limb grip test.

RESULTS

According to previous studies, 12 weeks of HFD induced NASH in all foz/foz mice. Increase of hepatic ammonia production and alterations of urea cycle efficiency were observed, leading to hyperammonemia. Concomitantly mice developed marked myosteatosis. First signs of myopenia occurred after 20 weeks of diet. Early LOLA treatment given during NASH development, but not its administration in a curative regimen, efficiently prevented myosteatosis and muscle quality, but barely impacted liver disease or, surprisingly, ammonia detoxification.

CONCLUSION

Our study confirms the perturbation of hepatic ammonia detoxification pathways in NASH. Results from the interventional experiments suggest a direct beneficial impact of LOLA on skeletal muscle during NASH development, though it does not improve ammonia metabolism or liver disease.

Impacts of muscle mass dynamics on prognosis of outpatients with cirrhosis

BACKGROUND/AIMS

Sarcopenia negatively affects the prognosis of cirrhotic patients, but clinical implications of changes in muscle mass remain unclear. We aimed to elucidate its role in the prognosis of outpatients with cirrhosis.

METHODS

Patients with cirrhosis who underwent annual abdominal computed tomography (CT) for hepatocellular carcinoma surveillance were included in the prospective cohort. The L3 skeletal muscle index (SMI) was adopted as a proxy for the amount of skeletal muscle, and the rate of SMI change between inclusion and after 1 year (ΔSMI/yr%) was calculated.

RESULTS

In total, 595 patients underwent a second CT after 1 year. Among them, 109 and 64 patients had sarcopenia and Child-Pugh class B/C decompensation at inclusion, which changed to 103 and 45 at the 1-year follow-up, respectively. During a median follow-up of 30.1 months after 1 year, 86 patients had at least one cirrhosis complication, and 18 died or received liver transplantation. In the development of cirrhosis complications, ΔSMI/yr% was independently associated, even after adjusting for the Child-Pugh and model for end stage liver disease (MELD)-Na scores. In addition, ΔSMI/yr% showed a good predictive performance for the development of cirrhosis complications within 6 months after 1-year follow-up in all subgroups, with a cut-off of -2.62 (sensitivity, 83.9%; specificity, 74.5%) in the overall population. SMI at 1-year and Child-Pugh score were independent factors associated with survival. In addition, changes in sarcopenia status significantly stratified survival.

CONCLUSION

ΔSMI/yr% was a good predictor of the development of cirrhosis complications in outpatients with cirrhosis, independent of Child-Pugh and MELD scores.

Hepatic encephalopathy

Hepatic encephalopathy (HE) is a prognostically relevant neuropsychiatric syndrome that occurs in the course of acute or chronic liver disease. Besides ascites and variceal bleeding, it is the most serious complication of decompensated liver cirrhosis. Ammonia and inflammation are major triggers for the appearance of HE, which in patients with liver cirrhosis involves pathophysiologically low-grade cerebral oedema with oxidative/nitrosative stress, inflammation and disturbances of oscillatory networks in the brain. Severity classification and diagnostic approaches regarding mild forms of HE are still a matter of debate. Current medical treatment predominantly involves lactulose and rifaximin following rigorous treatment of so-called known HE precipitating factors. New treatments based on an improved pathophysiological understanding are emerging.

Prognostic significance of cachexia index in patients with advanced hepatocellular carcinoma treated with systemic chemotherapy

Cancer cachexia affects quality of life, response to chemotherapy, and survival in many advanced cancer patients. The aim of this study was to evaluate the prognostic value of pretreatment cachexia index (CXI) in patients with advanced hepatocellular carcinoma (HCC) treated with systematic chemotherapy. Patients with advanced HCC treated with lenvatinib therapy between October 2018 and October 2020 were retrospectively studied. The CXI was calculated as (L3 skeletal muscle index) × (serum albumin)/(neutrophil-to-lymphocyte ratio). The association with treatment response and early adverse events within the first two months of lenvatinib therapy was investigated. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan–Meier method with log-rank test. Multivariable Cox regression was used to identify the predictors of survival. A total of 116 patients (median age: 60, male: 84.5% ) with calculated CXI. They divided into two groups: high CXI (≥ 53, n = 82) and low CXI (< 53, n = 34). Patients with low CXI had a significantly lower disease control rate (61.8% vs. 89.0%, p = 0.001) and a shorter median OS (8.0 [95% CI 6.2–9.8] vs. 12.3 [95% CI 10.1–14.4] months, p = 0.002) than those with high CXI. In multivariable analysis, low CXI was independently associated with shorter OS (HR: 2.07, 95% CI: 1.17–3.65, p = 0.01) and PFS (HR: 1.84, 95% CI: 1.09–3.09, p = 0.02). Of note, during the first two months of lenvatinib therapy, anorexia (41.2% vs. 22.0%, p = 0.04) developed more frequently among patients with low CXI than those with high CXI. The CXI may be a clinically useful index for predicting poor treatment response and prognosis in patients with advanced HCC undergoing lenvatinib treatment.

Effects of supervised exercise on aerobic capacity and quality of life in patients with chronic liver disease and patients who underwent liver transplantation: a systematic review and meta-analysis

Chronic liver disease and liver transplantation are risk factors for poor physical health and quality of life. This meta-analysis aimed to examine whether supervised exercise improves the physical health and quality of life in patients with chronic liver disease and liver transplant. Articles were searched in four databases (MEDLINE, Cochrane, Embase, and the Web of Science) from 1 January 1990 to 6 July 2021. Studies that assessed the change in aerobic capacity and quality of life following supervised exercise in patients with chronic liver disease or in those who had undergone liver transplantation were included in this meta-analysis. The two independent reviewers extracted data and the methodological quality of the included studies was assessed by the Cochrane Handbook for Systematic Reviews of Interventions. The extracted data were statistically analyzed using review management software (RevMan 5.3). The meta-analysis included 11 studies, comprising 159 patients. We observed that aerobic capacity measured as VO2 peak and 6-min walking test improved in patients with chronic liver disease and liver transplant after supervised exercise. Among the parameters of Short-form-36 (SF-36) used for measuring the quality of life, only physical functioning improved after supervised exercise. The other parameters of SF-36 including role-physical, bodily pain, general health, vitality, social functioning, role-emotional, and mental health were not significantly improved after supervised exercise. Supervised exercise seems essential for patients with chronic liver disease and liver transplant. It was found to be helpful in enhancing the aerobic capacity and physical function in these patients.

Effects of Branched-Chain Amino Acids on Parameters Evaluating Sarcopenia in Liver Cirrhosis: Systematic Review and Meta-Analysis

INTRODUCTION

Sarcopenia is a major element of malnutrition in liver cirrhosis (LC) and is present in 30-70% of this population, being associated with a poor overall prognosis due to related complications such as hepatic encephalopathy, ascites, and portal hypertension. This systematic review and meta-analysis aimed to evaluate the effects of branched-chain amino acids (BCAA) supplementation on several parameters used to assess sarcopenia in LC.

MATERIALS AND METHODS

A comprehensive systematic electronic search was performed in PubMed, EMBASE, Scopus, Cochrane Library, and ClinicalTrials.gov databases using predefined keywords. We included full articles that satisfied the inclusion and exclusion criteria. Quality assessment of included studies was conducted using Cochrane Collaboration's tool and NHLBI quality assessment tools for interventional and observational studies, respectively. The principal summary outcome was the mean difference (MD) in the evaluated parameters. We performed a pre- and post-intervention analysis and comparison between two intervention groups (BCAA vs. controls) of the evaluated parameters when applicable.

RESULTS

A total of 12 studies involving 1,225 subjects were included in our qualitative synthesis and five in our quantitative synthesis. At baseline vs. post-intervention assessment, subjects receiving BCAA supplementation were found to have a significant improvement in skeletal muscle index (SMI) (-0.347 [95% CI -0.628-0.067; p-value 0.015]) and mid-arm muscle circumference (MAMC) (-1.273 [95% CI (-2.251-0.294; p-value 0.011]). However, no improvements were reported in handgrip (-0.616 [95% CI -2.818-1.586; p-value 0.584]) and triceps subcutaneous fat (1.10 [95% CI -0.814-3.014; p-value 0.263]).

CONCLUSION

Following BCAA supplementation, several parameters used to evaluate sarcopenia in LC patients were found to be improved, including SMI and MAMC. Nevertheless, no improvements were seen in handgrip and triceps subcutaneous fat. Results should be interpreted with caution due to the limited methodological quality of the included studies.

Ammonia and the Muscle: An Emerging Point of View on Hepatic Encephalopathy

In the last years the link between the presence of muscular alterations and hepatic encephalopathy (HE), both minimal and overt, has been deeply studied. The pathophysiological background supporting the relationship between muscle depletion, and HE is characterized by an imbalance between the capacity of muscle in ammonia metabolism and trafficking and the inability of the liver in removing ammonia through urea synthesis due to liver failure and/or the presence of porto-systemic shunts. This review will focus on the clinical burden, the physio pathological mechanisms understanding the liver muscle axis and principles of management of muscular alterations in cirrhosis.

Myostatin: Basic biology to clinical application

Myostatin is a member of the transforming growth factor (TGF)-β superfamily. It is expressed by animal and human skeletal muscle cells where it limits muscle growth and promotes protein breakdown. Its effects are influenced by complex mechanisms including transcriptional and epigenetic regulation and modulation by extracellular binding proteins. Due to its actions in promoting muscle atrophy and cachexia, myostatin has been investigated as a promising therapeutic target to counteract muscle mass loss in experimental models and patients affected by different muscle-wasting conditions. Moreover, growing evidence indicates that myostatin, beyond to regulate skeletal muscle growth, may have a role in many physiologic and pathologic processes, such as obesity, insulin resistance, cardiovascular and chronic kidney disease. In this chapter, we review myostatin biology, including intracellular and extracellular regulatory pathways, and the role of myostatin in modulating physiologic processes, such as muscle growth and aging. Moreover, we discuss the most relevant experimental and clinical evidence supporting the extra-muscle effects of myostatin. Finally, we consider the main strategies developed and tested to inhibit myostatin in clinical trials and discuss the limits and future perspectives of the research on myostatin.

Sarcopenia in Hepatocellular Carcinoma: Pathogenesis and Management

BACKGROUND

Sarcopenia is almost constantly observed in patients with cirrhosis and hepatocellular carcinoma.

SUMMARY

Chronic liver disease represents a unique pathophysiological scenario in which sarcopenia develops and all factors involved in the pathogenesis should be taken into account for an appropriate management of the disease. No properly designed intervention studies on this topic are available and, thus, no effective strategies have been developed for clinical practice. Apart from any targeted intervention, treatment and optimization of liver disease is crucial. Key Messages: In patients with cirrhosis and hepatocellular carcinoma, nutritional support to maintain and restore nutrition status, a targeted use of branched-chain amino acids and a guided physical exercise, should all be an integral part of the multidimensional assessment and tailored interventions.

Synbiotics Alleviate Hepatic Damage, Intestinal Injury and Muscular Beclin-1 Elevation in Rats after Chronic Ethanol Administration

The purpose of this study was to investigate the beneficial effects of synbiotics on liver damage, intestinal health, and muscle loss, and their relevance in rats with chronic ethanol feeding. Thirty Wistar rats fed with a control liquid diet were divided into control and synbiotics groups, which were respectively provided with water or synbiotics solution (1.5 g/kg body weight/day) for 2 weeks. From the 3rd to 8th week, the control group was divided into a C group (control liquid diet + water) and an E group (ethanol liquid diet + water). The synbiotics group was separated in to three groups, SC, ASE, and PSE. The SC group was given a control liquid diet with synbiotics solution; the ASE group was given ethanol liquid diet with synbiotics solution, and the PSE group was given ethanol liquid diet and water. As the results, the E group exhibited liver damage, including increased AST and ALT activities, hepatic fatty changes, and higher CYP2E1 expression. Intestinal mRNA expressions of occludin and claudin-1 were significantly decreased and the plasma endotoxin level was significantly higher in the E group. In muscles, beclin-1 was significantly increased in the E group. Compared to the E group, the PSE and ASE groups had lower plasma ALT activities, hepatic fatty changes, and CYP2E1 expression. The PSE and ASE groups had significantly higher intestinal occludin and claudin-1 mRNA expressions and lower muscular beclin-1 expression when compared to the E group. In conclusion, synbiotics supplementation might reduce protein expression of muscle protein degradation biomarkers such as beclin-1 in rats with chronic ethanol feeding, which is speculated to be linked to the improvement of intestinal tight junction and the reduction of liver damage.

Effects of branched-chain amino acid-rich supplementation on EWGSOP2 criteria for sarcopenia in older adults: a systematic review and meta-analysis

PURPOSE

According to criteria recommended by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), we analyzed the effects of branched-chain amino acid (BCAA)-rich supplements on muscle strength, muscle mass, and physical performance in older people.

METHODS

We searched PubMed, Embase, Cochrane Library, and CINAHL from inception until March 2021. Randomized controlled trials that examined the effect of BCAA-rich supplements on older people were included. Random-effects meta-analyses and sensitivity analyses were performed. Subgroup analyses were stratified by participant and supplementation characteristics. Meta-regression analyses were performed to examine the effect of continuous variables.

RESULTS

Thirty-five studies were included in this meta-analysis. Quality assessment revealed that 14 of 35 RCTs had some potential bias. The overall standardized mean difference (SMD) in muscle strength, muscle mass, and physical performance between the supplement and control groups was 0.35 (95% CI = [0.15, 0.55], P = 0.0007), 0.25 (95% CI = [0.10, 0.40], P = 0.0008), and 0.29 (95% CI = [0.00, 0.57], P = 0.05), respectively. Subgroup analysis revealed that essential amino acid supplementation improved handgrip strength more significantly than whey protein supplementation in older people. Meta-regression analysis revealed a significant linear relationship between improvements in handgrip strength and body mass index.

CONCLUSIONS

BCAA-rich supplementation by older people may have beneficial effects on muscle mass and strength. However, the included studies had high heterogeneity, and the results must be interpreted with caution.

PROSPERO REGISTRATION NUMBER

CRD42020206674.

Identifying areas of improvement in nursing knowledge regarding hepatic encephalopathy management

Hepatic encephalopathy (HE) is a reversible brain dysfunction caused by liver insufficiency and portosystemic shunting. Hepatic encephalopathy is a common complication of advanced liver disease and is on a rise with the increasing incidence of non-alcoholic steatohepatitis (NASH). Since partnership with nursing staff is a critical part of successful management of these complex patients, we conducted a survey assessing their knowledge regarding HE.169 nurses participated in the survey. We found that more than 30% of the nurses did not know that ammonia is one of the toxins responsible for causing hepatic encephalopathy. We also found that 20% of the nurses had difficulty answering questions regarding titration of lactulose to bowel movements. Dietary education is a significant area for improvement as 80% of the nurses wanted to restrict fat and carbohydrate intake in these patients. With this simple survey, we identified important knowledge gaps among experienced nurses at our institution. We believe that by improving knowledge through focused lectures, we can improve patient care and reduce the length of hospitalizations in patients with HE.

The role of transjugular intrahepatic portosystemic shunt in patients with portal hypertension: advantages and pitfalls

Transjugular intrahepatic portosystemic shunt (TIPS) is an effective interventional procedure to relieve portal hypertension, which is a main mechanism for the development of complications of liver cirrhosis (LC), such as variceal hemorrhage, ascites, and hepatorenal syndrome. However, the high incidence of adverse events after TIPS implementation limits its application in clinical practice. Esophageal variceal hemorrhage is one of the major indications for TIPS. Recently, preemptively performed TIPS has been recommended, as several studies have shown that TIPS significantly reduced mortality as well as rebleeding or failure to control bleeding in patients who are at high risk of treatment failure for bleeding control with endoscopic variceal ligation and vasoactive drugs. Meanwhile, recurrent ascites is another indication for TIPS with a proven survival benefit. TIPS may also be considered as an effective treatment for other LC complications, usually as an alternative therapy. Although there are concerns about the development of hepatic encephalopathy and hepatic dysfunction after TIPS implementation, careful patient selection using prognostic scores can lead to excellent outcomes. Assessments of cardiac and renal function prior to TIPS may also be considered to improve patient prognosis.

Psoas Muscle Density Predicts Occurrences of Hepatic Encephalopathy in Patients Receiving Transjugular Intrahepatic Portosystemic Shunts within 1 year

PURPOSE

We aimed to assess the efficacy of psoas density (PD) for predicting hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) procedures.

METHODS

Data were collected from patients who underwent TIPS procedures at a single institution between 2013 and 2019. PD was manually measured using software on unenhanced CT scans at the level of third lumbar vertebra. Laboratory and physical examination data were collected within 24 h after admission in order to compare the differences between patients with and without post-TIPS HE.

RESULTS

A total of 251 patients were included in this study. Among these patients, 77 (30.7%) developed post-TIPS HE within one year after TIPS creation. The threshold of PD for predicting HE was 51.24 Hounsfield unit (HU). PD values less than this threshold were correlated with an increased risk of HE (hazard ratio 0.92; 95% CI 0.89-0.95, P < 0.001). The area under the receiver operating characteristic curve (AUROC) of PD was 0.743 (95% CI 0.685-0.796), which was superior to Model for End-stage Liver Disease (MELD) (0.569, P = 0.007), albumin-bilirubin score (ALBI) (0.641, P = 0.018), and Child-Pugh score (0.583, P = 0.003).

CONCLUSION

PD measurement showed good HE predictive value in cirrhotic patients who underwent TIPS. This measure also performed better than MELD, ALBI and Child-Pugh.