Usefulness of Levocarnitine and/or Branched-Chain Amino Acids during Invasive Treatment for Hepatocellular Carcinoma

Safety and Preliminary Efficacy of Pembrolizumab Following Transarterial Chemoembolization for Hepatocellular Carcinoma: The PETAL Phase Ib Study

PURPOSE

Transarterial chemoembolization (TACE) may prime adaptive immunity and enhance immunotherapy efficacy. PETAL evaluated safety, preliminary activity of TACE plus pembrolizumab and explored mechanisms of efficacy.

PATIENTS AND METHODS

Patients with liver-confined hepatocellular carcinoma (HCC) were planned to receive up to two rounds of TACE followed by pembrolizumab 200 mg every 21 days commencing 30 days post-TACE until disease progression or unacceptable toxicity for up to 1 year. Primary endpoint was safety, with assessment window of 21 days from pembrolizumab initiation. Secondary endpoints included progression-free survival (PFS) and evaluation of tumor and host determinants of response.

RESULTS

Fifteen patients were included in the safety and efficacy population: 73% had nonviral cirrhosis; median age was 72 years. Child-Pugh class was A in 14 patients. Median tumor size was 4 cm. Ten patients (67%) received pembrolizumab after one TACE; 5 patients after two (33%). Pembrolizumab yielded no synergistic toxicity nor dose-limiting toxicities post-TACE. Treatment-related adverse events occurred in 93% of patients, most commonly skin rash (40%), fatigue, and diarrhea (27%). After a median follow-up of 38.5 months, objective response rate 12 weeks post-TACE was 53%. PFS rate at 12 weeks was 93% and median PFS was 8.95 months [95% confidence interval (CI): 7.30-NE (not estimable)]. Median duration of response was 7.3 months (95% CI: 6.3-8.3). Median overall survival was 33.5 months (95% CI: 11.6-NE). Dynamic changes in peripheral T-cell subsets, circulating tumor DNA, serum metabolites, and in stool bacterial profiles highlight potential mechanisms of action of multimodal therapy.

CONCLUSIONS

TACE plus pembrolizumab was tolerable with no evidence of synergistic toxicity, encouraging further clinical development of immunotherapy alongside TACE.

Use of Branched-Chain Amino Acids as a Potential Treatment for Improving Nutrition-Related Outcomes in Advanced Chronic Liver Disease

Advanced chronic liver disease (ACLD) represents a complex and multifactorial clinical entity characterized by liver dysfunction and associated complications. In recent years, the significance of nutritional status in ACLD prognosis has gained considerable attention. This review article delves into the multifactorial pathogenesis of malnutrition in ACLD and its profound consequences for health outcomes. We explore the clinical implications of secondary sarcopenia in ACLD and highlight the critical relevance of frailty in both decompensated and compensated ACLD. A specific focus of this review revolves around branched-chain amino acids (BCAAs) and their pivotal role in managing liver disease. We dissect the intricate relationship between low Fischer's ratio and BCAA metabolism in ACLD, shedding light on the molecular mechanisms involved. Furthermore, we critically evaluate the existing evidence regarding the effects of BCAA supplementation on outcomes in ACLD patients, examining their potential to ameliorate the nutritional deficiencies and associated complications in this population.

Systematic review with meta-analysis: Branched-chain amino acid supplementation in liver disease

BACKGROUND

Dietary supplementation with branched-chain amino acids (BCAA) is often used in cirrhotic patients to improve nutritional status. We wanted to explore the evidence for BCAA supplementation in chronic liver disease.

METHODS

We searched MEDLINE and EMBASE for studies with BCAA supplementation with the presence of a disease-control group (placebo or no intervention) using search terms 'liver cirrhosis', 'hepatocellular carcinoma', 'branched chain amino acids' and relevant synonyms. Risk of bias was assessed using ROBINS-I and RoB 2.0 tools. Meta-analyses were performed with a random-effects model. Results were reported following EQUATOR guidelines.

RESULTS

Of 3378 studies screened by title and abstract, 54 were included (34 randomized controlled trials, 5 prospective case-control studies, 13 retrospective case-control studies: in total 2308 patients BCAA supplementation, 2876 disease-controls). Risk of bias was high/serious for almost all studies. According to meta-analyses, long-term (at least 6 months) BCAA supplementation in cirrhotic patients significantly improved event-free survival (p = .008; RR .61 95% CI .42-.88) and tended to improve overall survival (p = .05; RR .58 95% CI .34-1.00). Two retrospective studies suggested the beneficial effects during sorafenib for hepatocellular carcinoma. Available studies reported no beneficial effects or contradictory results of BCAA after other specific therapeutic interventions (resection or radiological interventions for hepatocellular carcinoma, liver transplantation, paracentesis or variceal ligation). No convincing beneficial effects of BCAA supplementation on liver function, nutritional status or quality of life were found. No study reported serious side effects of BCAA.

CONCLUSIONS

Prophylactic BCAA supplementation appears safe and might improve survival in cirrhotic patients.

Carnitine derivatives beyond fatigue: an update

PURPOSE OF REVIEW

Carnitine is an essential micronutrient that transfer long-chain fatty acids from the cytoplasm into the mitochondrial matrix for the β-oxidation. Carnitine is also needed for the mitochondrial efflux of acyl groups in the cases wherein substrate oxidation exceeds energy demands.

RECENT FINDINGS

Carnitine deficiency can affect the oxidation of free fatty acids in the mitochondria resulting in the aggregation of lipids in the cytoplasm instead of entering the citric acid cycle. The aggregation leads a lack of energy, acetyl coenzyme A accumulation in the mitochondria and cytotoxic production.

SUMMARY

Carnitine and its derivatives show great clinical therapeutic effect without significant side effects.

The Role of Branched-Chain Amino Acid Supplementation in Combination with Locoregional Treatments for Hepatocellular Carcinoma: Systematic Review and Meta-Analysis

BACKGROUND

Branched-chain amino acid (BCAA) supplementation has been linked with favorable outcomes in patients undergoing surgical or palliative treatments for hepatocellular carcinoma (HCC). To date, there has been no systematic review investigating the value of BCAA supplementation in HCC patients undergoing locoregional therapies.

MATERIALS AND METHODS

A systematic search of the literature was performed across five databases/registries using a detailed search algorithm according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. The search was conducted on March 23, 2022.

RESULTS

Sixteen studies with a total of 1594 patients were analyzed. Most patients were male (64.6%) with a mean age of 68.2 ± 4.1 years, Child-Pugh score A (67.9%) and stage II disease (40.0%). Locoregional therapy consisted of radiofrequency ablation, transarterial chemoembolization or hepatic artery infusion chemotherapy. BCAA supplementation was in the form of BCAA granules or BCAA-enriched nutrient. Most studies reported improved albumin levels, non-protein respiratory quotient and quality of life in the BCAA group. Results pertaining to other outcomes including overall survival, recurrence rate, and Child-Pugh score were variable. Meta-analysis showed significantly higher levels of post-treatment serum albumin in the BCAA group (SMD = 0.54, 95% CI 0.20-0.87) but no significant differences in mortality rate (RR = 0.81, 95% CI: 0.65-1.02) and AST (SMD = -0.13, 95% CI: -0.43-0.18).

CONCLUSION

BCAA supplementation is associated with higher post-treatment albumin levels. There are currently not sufficient data to support additional benefits. Further studies are needed to elucidate their value.

Branched-chain amino acids and l-carnitine attenuate lipotoxic hepatocellular damage in rat cirrhotic liver

Branched-chain amino acids (BCAA) reverse malnutrition and l-carnitine leads to the reduction of hyperammonemia and muscle cramps in cirrhotic patients. BCAA and l-carnitine are involved in glucose and fatty acid metabolism, however their mechanistic activity in cirrhotic liver is not fully understood. We aim to define the molecular mechanism(s) and combined effects of BCAA and l-carnitine using a cirrhotic rat model. Rats were administered carbon tetrachloride for 10 weeks to induce cirrhosis. During the last 6 weeks of administration, cirrhotic rats received BCAA, l-carnitine or a combination of BCAA and l-carnitine daily via gavage. We found that BCAA and l-carnitine treatments significantly improved hepatocellular function associated with reduced triglyceride level, lipid deposition and adipophilin expression, in cirrhotic liver. Lipidomic analysis revealed dynamic changes in hepatic lipid composition by BCAA and l-carnitine administrations. BCAA and l-carnitine globally increased molecular species of phosphatidylcholine. Liver triacylglycerol and phosphatidylcholine hydroperoxides were significantly decreased by BCAA and l-carnitine. Furthermore, serum and liver ATP levels were significantly increased in all treatments, which were attributed to the elevation of mature cardiolipins and mitochondrial component gene expressions. Finally, BCAA and l-carnitine dramatically reduced hepatocellular death. In conclusion, BCAA and l-carnitine treatments attenuate hepatocellular damage through the reduction of lipid peroxides and the overall maintenance of mitochondrial integrity within the cirrhotic liver. These effectiveness of BCAA and l-carnitine support the therapeutic strategies in human chronic liver diseases.

Multifaceted role of branched-chain amino acid metabolism in cancer

Metabolic reprogramming fulfils increased nutrient demands and regulates numerous oncogenic processes in tumors, leading to tumor malignancy. Branched-chain amino acids (BCAAs, i.e., valine, leucine, and isoleucine) function as nitrogen donors to generate macromolecules such as nucleotides and are indispensable for human cancer cell growth. The cell-autonomous and non-autonomous roles of altered BCAA metabolism have been implicated in cancer progression and the key proteins in the BCAA metabolic pathway serve as possible prognostic and diagnostic biomarkers in human cancers. Here we summarize how BCAA metabolic reprogramming is regulated in cancer cells and how it influences cancer progression.

Levocarnitine Use Is Associated With Improvement in Sarcopenia in Patients With Liver Cirrhosis

Although the effect of levocarnitine (L-carnitine) on hyperammonemia has been reported in patients with liver cirrhosis (LC), its effect on sarcopenia remains to be elucidated. We assessed the effects of L-carnitine on sarcopenia in patients with LC. We retrospectively evaluated 52 patients with LC who were treated with L-carnitine for more than 3 months between February 2013 and June 2017. Computed tomography was used to measure the cross-sectional area of the skeletal muscles at the level of the third lumbar vertebra. The relative change in skeletal muscle index (SMI) per year (ΔSMI/year) was computed in each patient. We evaluated the relationship between ΔSMI/year and various parameters, such as age, sex, liver functional reserve, and dose of L-carnitine. The median ΔSMI/year for all patients was -0.22%. The ΔSMI/year values in Child-Pugh classes A, B, and C were not significantly different among the three groups. There was no significant relationship between ΔSMI/year and sex, age, body mass index, and sarcopenia. Multivariate analysis showed that only a high dose of L-carnitine (odds ratio [OR], 4.812; 95% confidence interval [CI], 1.233-18.784; P = 0.024) was associated with increased muscle mass. The L-carnitine high-dose group included a significantly larger number of patients with increased muscle mass compared with the low-dose group (OR, 3.568; 95% CI, 1.138-11.185; P = 0.027). Administration of L-carnitine led to a significant and gradual reduction in serum ammonia levels. Conclusion: L-carnitine seems to suppress the progression of sarcopenia dose dependently, and this was noted to be associated with the improvement of hyperammonemia in patients with LC.

Effects of branched chain amino acid supplementation on patient care outcomes in adults and children with liver cirrhosis: A systematic review

BACKGROUND & AIMS

Malnutrition is highly prevalent in chronic liver disease (CLD) due to alterations in nutrient utilization, malabsorption and poor intake. Low serum concentrations of branched chain amino acids (BCAA) in the presence of elevated aromatic acid concentrations is commonly observed in adult and children with liver cirrhosis and is associated with malnutrition and other adverse patient outcomes. The efficacy of BCAA supplementation has not been well established in adults and children with CLD. The purpose of this review was to critically evaluate the literature regarding the impact of BCAA supplementation related to changes in body composition, muscle strength, liver biomarkers, medical and hepatic complications (hepatic encephalopathy (HE), ascites, edema) and patient care outcomes (event free survival, health related quality of life, length of hospitalization).

METHODS

A total of 40 articles retrieved from PubMed or Web of Science databases (1989-2017) were included.

RESULTS

BCAA supplementation may be beneficial in improving muscle strength, ascites and edema with potential clinically significant improvements in HE in adult liver patients. In children, limited data have shown that BCAA supplementation may exert favourable effects on weight, fat mass, fat free mass and serum albumin level.

CONCLUSIONS

Heterogeneity of study findings attributed to variability in BCAA dose (total, relative proportions), duration, disease severity and lack of uniformity in tools used for assessing patient outcomes limit overall conclusions. Longitudinal studies examining the efficacy of BCAA supplementation as a therapeutic treatment of malnutrition in chronic liver disease is warranted.

Branched-chain amino acid metabolism in cancer

PURPOSE OF REVIEW

The current review aims to provide an update on the recent biomedical interest in oncogenic branched-chain amino acid (BCAA) metabolism, and discusses the advantages of using BCAAs and expression of BCAA-related enzymes in the treatment and diagnosis of cancers.

RECENT FINDINGS

An accumulating body of evidence demonstrates that BCAAs are essential nutrients for cancer growth and are used by tumors in various biosynthetic pathways and as a source of energy. In addition, BCAA metabolic enzymes, such as the cytosolic branched-chain aminotransferase 1 (BCAT1) and mitochondrial branched-chain aminotransferase 2, have emerged as useful prognostic cancer markers. BCAT1 expression commonly correlates with more aggressive cancer growth and progression, and has attracted substantial scientific attention in the past few years. These studies have found the consequences of BCAT1 disruption to be heterogeneous; not all cancers share the same requirements for BCAA metabolites and the function of BCAT1 appears to vary between cancer types.

SUMMARY

Both oncogenic mutations and cancer tissue-of-origin influence BCAA metabolism and expression of BCAA-associated metabolic enzymes. These new discoveries need to be taken into consideration during the development of new cancer therapies that target BCAA metabolism.

L-Carnitine for the Treatment of Overt Hepatic Encephalopathy in Patients with Advanced Liver Cirrhosis

Hepatic encephalopathy is a major complication in patients with advanced cirrhosis and is associated with poor prognosis. To evaluate the effectiveness of L-carnitine supplementation in patients with overt hepatic encephalopathy (OHE), outcomes were retrospectively analyzed in patients with OHE who were treated with intravenous branched-chain amino acids (BCAA), with or without intravenous L-carnitine. Twenty-six patients were treated with intravenous BCAA in addition to conventional agents such as lactulose and non-absorbable antibiotics (Group A), and 19 patients were treated with these agents plus intravenous L-carnitine (Group L). Changes in blood ammonia concentrations, hepatic coma grade and the Glasgow Coma Scale (GCS) were compared in the two groups. Recurrence-free survival (RFS) was evaluated in the two groups and in patients who were and were not administered oral L-carnitine supplementation. At baseline, GCS scores were significantly lower and deterioration in liver function greater in Group L. After 3 d of intravenous L-carnitine, however, GCS showed a significantly greater improvement in Group L than in Group A. Blood ammonia levels improved stably over time in Group L. Overall survival and RFS were similar in Group L and Group A, but median RFS was significantly longer in patients who did than did not receive oral L-carnitine supplementation (735 versus 497 d, p=0.03). Although these findings are preliminary, L-carnitine supplementation may be a therapeutic option for patients with OHE and disturbed consciousness.

Carnitine dynamics and their effects on hyperammonemia in cirrhotic Japanese patients

AIM

Supplementation with levocarnitine preparations has been reported to improve hepatic encephalopathy, but no detailed investigations have addressed the dynamics of carnitine or its supplementation indication in cirrhosis patients. We studied carnitine dynamics in cirrhotic patients by measuring serum and liver tissue carnitine levels and tested the effects of levocarnitine supplementation on concurrent hyperammonemia.

METHODS

In a pilot cohort of seven patients with liver cirrhosis and five patients without cirrhosis, the serum and liver carnitine concentrations were measured. Then the serum carnitine fractions were analyzed in 70 liver cirrhosis patients. Among them, a levocarnitine preparation (1800 mg/day) was supplemented orally for 3 months in 27 patients with refractory hyperammonemia, and the effects were evaluated.

RESULTS

A significant correlation was observed between serum and liver tissue carnitine concentrations (r = 0.69, P < 0.05). The serum total carnitine concentration was 68.4 ± 4.7 μmol/L, the free carnitine concentration was 53.2 ± 2.6 μmol/L, and the acylcarnitine concentration was 13.2 ± 1.1 μmol/L in 70 cirrhotic patients (reference values are 45-91, 36-74, 6-23 μmol/L, respectively). There was no correlation between blood ammonia and serum carnitine concentrations. The serum carnitine concentration rose with levocarnitine supplementation, reaching steady state after 1 month and, in parallel, refractory hyperammonemia was significantly improved. The cut-off level for a 20% decrease in blood ammonia was identified as 62.0 μmol/L total carnitine concentration by receiver-operating characteristic curve analysis, with an area under the curve of 0.69.

CONCLUSION

Serum carnitine concentrations were within standard levels in the majority of liver cirrhosis patients. In patients with concurrent hyperammonemia, the levocarnitine supplementation reduced blood ammonia levels.