Serum interleukin-6 and tumor necrosis factor-α are associated with early graft regeneration after living donor liver transplantation

A proof-of-concept study in small and large animal models for coupling liver normothermic machine perfusion with mesenchymal stromal cell bioreactors

To fully harness mesenchymal-stromal-cells (MSCs)' benefits during Normothermic Machine Perfusion (NMP), we developed an advanced NMP platform coupled with a MSC-bioreactor and investigated its bio-molecular effects and clinical feasibility using rat and porcine models. The study involved three work packages: 1) Development (n = 5): MSC-bioreactors were subjected to 4 h-liverless perfusion; 2) Rat model (n = 10): livers were perfused for 4 h on the MSC-bioreactor-circuit or with the standard platform; 3) Porcine model (n = 6): livers were perfused using a clinical device integrated with a MSC-bioreactor or in its standard setup. MSCs showed intact stem-core properties after liverless-NMP. Liver NMP induced specific, liver-tailored, changes in MSCs' secretome. Rat livers exposed to bioreactor-based perfusion produced more bile, released less damage and pro-inflammatory biomarkers, and showed improved mithocondrial function than those subjected to standard NMP. MSC-bioreactor integration into a clinical device resulted in no machine failure and perfusion-related injury. This proof-of-concept study presents a novel MSC-based liver NMP platform that could reduce the deleterious effects of ischemia/reperfusion before transplantation.

Development and validation of a model for early survival prediction following liver transplantation based on donor and recipient characteristics

BACKGROUND

Circulating cytokine levels not only correlate with the progression of liver disease but also serve as indicators for the infection status of the body. Growing evidence points to the connection between donor cytokines and graft function following transplantation. This study set out to explore the clinical significance of donor cytokines in predicting liver transplantation prognosis.

METHODS

Data from 172 deceased donor liver transplantations conducted between 2017 and 2022, with available donor serum cytokine information, were collected. The subjects were randomly divided into estimation (n = 120) and validation (n = 52) groups to establish and validate the model. The newly developed SA10 score was compared against established models EAD, MEAF, L-GrAFT7, and L-GrAFT10.

RESULTS

Donor IL-10, along with donor age and recipient AST peak value within the first 7 days post-operation, was identified as an independent factor associated with recipient survival and was incorporated into the SA10 score. SA10 exhibited robust predictive capability, particularly for 1-month survival (AUC = 0.90, 95% CI = 0.84-0.96), outperforming EAD (AUC = 0.75, 95% CI = 0.60-0.90, p = 0.04) and L-GrAFT7 (AUC = 0.65, 95% CI = 0.49-0.81, p < 0.01). Comparable performance was observed between SA10, MEAF, and L-GrAFT10.

CONCLUSION

Donor IL-10 independently influences recipient survival, with the SA10 score demonstrating comparable and even superior predictive ability compared to existing models.

Metabolomic Analysis and Biochemical Profiling of Cadmium-Induced Metabolic Impairment and Its Amelioration by Resveratrol

Exposure to heavy metals, particularly cadmium (Cd), poses significant health risks because of their toxic effects and potential for bioaccumulation in living organisms. This study examined the biochemical and metabolomic changes induced by Cd exposure in an animal model via advanced liquid chromatography with tandem mass spectrometry (LC-MS/MS) and biochemical assays to reveal significant disruptions in lipid and amino acid metabolism as well as alterations in key metabolic pathways. Cd exposure led to significant weight loss, hyperglycemia, and insulin resistance, indicating its role in metabolic disorders such as diabetes. The accumulation of Cd in the liver and kidneys, identified via ICP-OES, corresponded with elevated levels of liver (ALT, AST) and kidney (BUN, creatinine) biomarkers, suggesting organ-specific toxicity. At the metabolic level, Cd exposure caused the accumulation of lipid metabolites such as ceramides and sphingolipids, which are associated with insulin resistance and broader metabolic impairments. Amino acid metabolism was also significantly disrupted, with increased concentrations of key amino acids such as phenylalanine, tryptophan, and arginine affecting pathways such as the urea cycle and Krebs cycle. These metabolic disturbances are linked to oxidative stress, systemic inflammation, and impaired glucose regulation, as evidenced by elevated CRP and IL-6 levels. The protective effects of resveratrol (RSV) were clearly demonstrated in this study. RSV treatment ameliorated Cd-induced biochemical and metabolic alterations, as shown by improved glycemic control, restored lipid profiles, and normalized amino acid concentrations. Additionally, RSV significantly reduced inflammatory markers and improved liver and kidney function, highlighting its antioxidant properties and potential as a therapeutic agent against Cd toxicity. However, RSV did not significantly reduce Cd accumulation in organs, indicating that its protective effects are related to mitigating oxidative damage and metabolic disruption rather than promoting Cd excretion. This study enhances our understanding of the molecular mechanisms underlying Cd-induced metabolic impairments and highlights the therapeutic potential of RSV in combating Cd toxicity. These findings underscore the need for further research into heavy metal exposure and its mitigation to protect human health, particularly in areas of environmental contamination.

Growth differentiation factor 15: Emerging role in liver diseases

Growth differentiation factor 15 (GDF15) is a cell stress-response cytokine within the transforming growth factor-β (TGFβ) superfamily. It is known to exert diverse effects on many metabolic pathways through its receptor GFRAL, which is expressed in the hindbrain, and transduces signals through the downstream receptor tyrosine kinase Ret. Since the liver is the core organ of metabolism, summarizing the functions of GDF15 is highly important. In this review, we assessed the relevant literature regarding the main metabolic, inflammatory, fibrogenic, tumorigenic and other effects of GDF15 on different liver diseases, including Metabolic dysfunction-associated steatotic liver disease(MASLD), alcohol and drug-induced liver injury, as well as autoimmune and viral hepatitis, with a particular focus on the pathogenesis of MASLD progression from hepatic steatosis to MASH, liver fibrosis and even hepatocellular carcinoma (HCC). Finally, we discuss the prospects of the clinical application potential of GDF15 along with its research and development progress. With better knowledge of GDF15, increasing in-depth research will lead to a new era in the field of liver diseases.

PFKFB3-mediated glycolysis in hepatic stellate cells promotes liver regeneration

Hepatic stellate cells (HSCs) perform a significant function in liver regeneration (LR) by becoming active. We propose to investigate if activated HSCs enhance glycolysis via PFKFB3, an essential glycolytic regulator, and whether targeting this pathway could be beneficial for LR. The liver and isolated HSCs of mice subjected to 2/3 partial hepatectomy (PHx) exhibited a significant rise in PFKFB3 expression, as indicated by quantitative RT-PCR analyses and Western blotting. Also, the primary HSCs of mice subjected to PHx have a significant elevation of the glycolysis level. Knocking down PFKFB3 significantly diminished the enhancement of glycolysis by PDGF in human LX2 cells. The hepatocyte proliferation in mice treated with PHx was almost completely prevented when the PFKFB3 inhibitor 3PO was administered, emerging that PFKFB3 is essential in LR. Furthermore, there was a decline in mRNA expression of immediate early genes and proinflammatory cytokines. In terms of mechanism, both the p38 MAP kinase and ERK1/2 phosphorylation in LO2 cells and LO2 proliferation were significantly reduced by the conditioned medium (CM) obtained from LX2 cells with either PFKFB3 knockdown or inhibition. Compared to the control group, isolated hepatocytes from 3PO-treated mice showed decreased p38 MAP kinase and ERK1/2 phosphorylation and proliferation. Thus, LR after PHx involves the activation of PFKFB3 in HSCs, which enhances glycolysis and promotes lactate production, thereby facilitating hepatocyte proliferation via the p38/ERK MAPK signaling pathway.

Signaling pathways of liver regeneration: Biological mechanisms and implications

The liver possesses a unique regenerative ability to restore its original mass, in this regard, partial hepatectomy (PHx) and partial liver transplantation (PLTx) can be executed smoothly and safely, which has important implications for the treatment of liver disease. Liver regeneration (LR) can be the very complicated procedure that involves multiple cytokines and transcription factors that interact with each other to activate different signaling pathways. Activation of these pathways can drive the LR process, which can be divided into three stages, namely, the initiation, progression, and termination stages. Therefore, it is important to investigate the pathways involved in LR to elucidate the mechanism of LR. This study reviews the latest research on the key signaling pathways in the different stages of LR.

The Effects of Hepatogomax Enteral Formula on Systemic Inflammation, Caecum Short-Chain Fatty Acid Levels, and Liver Histopathology in Thioacetamide-Induced Rats

Liver damage characterized by fibrosis and necrosis can worsen the condition of liver disease. Liver disease is associated with impaired immune response and may affect short-chain fatty acid (SCFA) gut metabolites. Hepatogomax enteral formula was developed, which contains brain-chain amino acids (BCAAs) and middle-chain triglycerides (MCTs), which could repair liver tissue damage, improve the inflammatory status, and modulate SCFA in liver damage. The study aimed to determine the effect of hepatogomax on liver tissue repair, inflammation (TNF-α and IL-6), and SCFA levels in thioacetamide (TAA)-induced rats. The induction of TAA causes liver steatosis, increasing TNF-α and IL-6, and decreasing SCFA levels. Hepatogomax at a dose of 14.6 g/200 gBW significantly reduces TNF-α and IL-6 levels and increases SCFA levels (p < 0.05). The number of steatosis between groups P2 and P3 was lower as compared to a group of negative control [K2] (p < 0.05). Hepatogomax, in a dose-dependent manner, may repair liver tissue and improve inflammatory response and SCFA levels in TAA-induced rats.

The Effects of Tissue Healing Factors in Wound Repair Involving Absorbable Meshes: A Narrative Review

Wound healing is a complex and meticulously orchestrated process involving multiple phases and cellular interactions. This narrative review explores the intricate mechanisms behind wound healing, emphasizing the significance of cellular processes and molecular factors. The phases of wound healing are discussed, focusing on the roles of immune cells, growth factors, and extracellular matrix components. Cellular shape alterations driven by cytoskeletal modulation and the influence of the 'Formin' protein family are highlighted for their impact on wound healing processes. This review delves into the use of absorbable meshes in wound repair, discussing their categories and applications in different surgical scenarios. Interleukins (IL-2 and IL-6), CD31, CD34, platelet rich plasma (PRP), and adipose tissue-derived mesenchymal stem cells (ADSCs) are discussed in their respective roles in wound healing. The interactions between these factors and their potential synergies with absorbable meshes are explored, shedding light on how these combinations might enhance the healing process. Recent advances and challenges in the field are also presented, including insights into mesh integration, biocompatibility, infection prevention, and postoperative complications. This review underscores the importance of patient-specific factors and surgical techniques in optimizing mesh placement and healing outcomes. As wound healing remains a dynamic field, this narrative review provides a comprehensive overview of the current understanding and potential avenues for future research and clinical applications.

Neuropsychiatric sequelae after liver transplantation and their possible mechanism via the microbiota-gut-liver-brain axis

Patients after liver transplantation are often impacted by mental and even neuropsychiatric disorders, including depression, sleep disorders, anxiety, and post-traumatic stress disorder. Neuropsychiatric sequelae have an adverse impact on rehabilitation and can even incapacitate people, reducing their quality of life. Despite screening tools and effective treatments, neuropsychiatric sequelae after liver transplantation (NSALT) have not been fully diagnosed and treated. Current research suggests that NSALT may be partly related to intestinal microbial variation, but the detailed mechanism remains unclear. In this review, we describe the clinical and diagnostic features, prevalence, prediction, clinical course and outcome, management, and treatment of NSALT; we also summarize their mechanisms through the microbiota-gut-liver-brain axis. Finally, we propose to improve NSALT on the basis of adjusting the gastrointestinal flora, immune inflammation or vagus nerve (VN), providing a novel strategy for clinical prevention and treatment.

Distinctive role of inflammation in tissue repair and regeneration

Inflammation is an essential host defense mechanism in response to microbial infection and tissue injury. In addition to its well-established role in infection, inflammation is actively involved in the repair of damaged tissues and restoration of homeostatic conditions after tissue injury. The intensity of the inflammatory response and types of cells involved in inflammation have a significant impact on the quality of tissue repair. Numerous immune cell subtypes participate in tissue repair and regeneration. In particular, immune cell-derived secretants, including cytokines and growth factors, can actively modulate the proliferation of resident stem cells or progenitor cells to facilitate tissue regeneration. These findings highlight the importance of inflammation during tissue repair and regeneration; however, the precise role of immune cells in tissue regeneration remains unclear. In this review, we summarize the current knowledge on the contribution of specific immune cell types to tissue repair and regeneration. We also discuss how inflammation affects the final outcome of tissue regeneration.

Leveraging the tolerogenic potential of TNF-α and regulatory B cells in organ transplantation

A subset of B-cells with tolerogenic functions, termed B-regulatory cells or Bregs, is characterized by the expression of anti-inflammatory/tolerogenic cytokines, namely IL-10, TGF-β, and IL-35, that contribute to their regulatory functions. Breg regulation favors graft acceptance within a tolerogenic milieu. As organ transplantation invariably triggers inflammation, new insights into the crosstalk between cytokines with dual properties and the inflamed milieu are needed to tailor their function toward tolerance. Using TNF-α as a proxy of dual-function cytokines involved in immune-related diseases and transplantation settings, the current review highlights the multifaceted role of TNF-α. It focuses on therapeutic approaches that have revealed the complexity of TNF-α properties tested in clinical settings where total TNF-α inhibition has proven ineffective and often detrimental to clinical outcomes. To improve the efficacy of current TNF-α inhibiting therapeutics, we propose a three-prong strategy to upregulate the tolerogenic pathway engaging the TNFR2 receptor while simultaneously inhibiting the inflammatory mechanisms associated with TNFR1 engagement. When combined with additional administrations of Bregs-TLR that activate Tregs, this approach may become a potential therapeutic in overcoming transplant rejection and promoting graft tolerance.

Concurrent Change in Serum Cholinesterase Activity and Midregional-Proadrennomedullin Level Could Predict Patient Outcome following Liver Transplantation

Background: After liver transplantation (LTX), patients are susceptible to opportunistic infections resulting in reduced outcomes within the early post-transplantation period. The postoperative monitoring of LTX patients has gained much importance in recent years. However, reliable plasmatic markers predicting 90-day outcomes are still lacking. Methods: In the post hoc analysis of a prospective, observational study, butyrylcholinesterase (BChE), mid-regional proadrenomedullin (MR-proADM), as well as conventional inflammatory markers (procalcitonin, C-reactive protein) were evaluated in 93 patients at seven consecutive timepoints within the first 28 days following LTX. Results: Persistently reduced activity of BChE and elevated MR-proADM levels indicated reduced 90-day survival following LTX. Furthermore, reduced BChE and increased MR-proADM activity could indicate early post-transplantation bacterial infections, whereas conventional inflammatory biomarkers showed no diagnostic efficacy within the observation period. Conclusion: Concurrent assessment of BChE and MR-proADM activity might serve as a bedside diagnostic tool for early bacterial infections following liver transplantation. Thus, a combined utilization of the two biomarkers may be a useful tool in the risk evaluation of patients following liver transplantation.

The Effects of Growth Factors and Cytokines on Hepatic Regeneration: A Systematic Review

The incidence of liver disease increases throughout the years due to many lifestyle factors; thus, the only definite treatment available for chronic liver disease is a liver transplant. However, the liver has a natural ability to repair itself and regenerate its hepatic tissue from stem cells. It is hypothesized that by inducing the liver with specific growth factors and cytokines such as interleukin 6 (IL-6) compared to general growth factors like growth differentiation factor 15 (GDF-15), it can regenerate, decreasing the need for liver transplant procedures. MEDLINE, the Journal of Hepatology, and Google Scholar were used to find articles. Various studies, including epidemiological studies dated from the year 2000 and greater, were used for the introduction. The results used only randomized control trials, experimental studies, and primary articles published since 2000. This compared the results of manipulating variables to determine the effects of hepatic regeneration by either specific hepatocyte growth factors or general growth factors like GDF-15. A total of 10 collected studies showed increased levels of gene expression and function, improved gross morphology, and histological appearance of the liver when induced by cytokines and specific growth factors versus general growth factors. Overall, the hypothesis was proven. The effects of GDF-15 were not significant compared to the effects of hepatocyte-specific growth factors and cytokines like IL-6 because they have two different effects on the liver after liver injury. Future studies should investigate this topic on the human hepatic regenerative ability, plus compare the effects of general growth factors like GDF-15 and specific hepatocyte growth factors and cytokines such as IL-6 in human liver tissue.

Mitochondrial bioenergetics boost macrophage activation, promoting liver regeneration in metabolically compromised animals

BACKGROUND AND AIMS

Hepatic ischemia-reperfusion injury (IRI) is the leading cause of early posttransplantation organ failure as mitochondrial respiration and ATP production are affected. A shortage of donors has extended liver donor criteria, including aged or steatotic livers, which are more susceptible to IRI. Given the lack of an effective treatment and the extensive transplantation waitlist, we aimed at characterizing the effects of an accelerated mitochondrial activity by silencing methylation-controlled J protein (MCJ) in three preclinical models of IRI and liver regeneration, focusing on metabolically compromised animal models.

APPROACH AND RESULTS

Wild-type (WT), MCJ knockout (KO), and Mcj silenced WT mice were subjected to 70% partial hepatectomy (Phx), prolonged IRI, and 70% Phx with IRI. Old and young mice with metabolic syndrome were also subjected to these procedures. Expression of MCJ, an endogenous negative regulator of mitochondrial respiration, increases in preclinical models of Phx with or without vascular occlusion and in donor livers. Mice lacking MCJ initiate liver regeneration 12 h faster than WT and show reduced ischemic injury and increased survival. MCJ knockdown enables a mitochondrial adaptation that restores the bioenergetic supply for enhanced regeneration and prevents cell death after IRI. Mechanistically, increased ATP secretion facilitates the early activation of Kupffer cells and production of TNF, IL-6, and heparin-binding EGF, accelerating the priming phase and the progression through G₁ /S transition during liver regeneration. Therapeutic silencing of MCJ in 15-month-old mice and in mice fed a high-fat/high-fructose diet for 12 weeks improves mitochondrial respiration, reduces steatosis, and overcomes regenerative limitations.

CONCLUSIONS

Boosting mitochondrial activity by silencing MCJ could pave the way for a protective approach after major liver resection or IRI, especially in metabolically compromised, IRI-susceptible organs.

Cytokines in Liver Transplantation

Cytokines, soluble mediators of the immune system, play a critical role in the pathogenesis of autoimmune, allergic and infectious diseases. They are also implicated in the initiation and development of allograft rejection. During recent years, there have been considerable advances in generating novel anti-cytokine agents with promoted efficacy and safety, which could be administrated for managing dysregulated cytokine secretion; besides, gene therapy for overexpression of immunomodulatory cytokines has shown substantial improvements. Liver transplantation has been established as a life-saving treatment for end-stage hepatic diseases but the growing number of recipients urge for improved post-transplant care including tolerance induction, infection control and resolving immunosuppressant drugs adverse effects. Cytokines with a wide range of proinflammatory and regulatory properties might be considered as potential therapeutic targets for selective suppression or enhancement of the immune responses in recipients. In the present review, we aimed to summarize the positive and negative effects of cytokines on liver allograft in addition to their prognostic and therapeutic values.

Sensing Acute Cellular Rejection in Liver Transplant Patients Using Liver-Derived Extracellular Particles: A Prospective, Observational Study

Acute cellular rejection (ACR) after liver transplantation (LT) goes along with allograft dysfunction, which is diagnosed by liver biopsy and concomitant histological analysis, representing the gold standard in clinical practice. Yet, liver biopsies are invasive, costly, time-intensive and require expert knowledge. Herein we present substantial evidence that blood plasma residing peripheral liver-derived extracellular particles (EP) could be employed to diagnose ACR non-invasively. In vitro experiments showed organ-specific EP release from primary human hepatocytes under immunological stress. Secondly, analysis of consecutive LT patients (n=11) revealed significant heightened EP concentrations days before ACR. By conducting a diagnostic accuracy study (n = 69, DRKS00011631), we explored the viability of using EP as a liquid biopsy for diagnosing ACR following LT. Consequently, novel EP populations in samples were identified using visualization of t-distributed stochastic neighbor embedding (viSNE) and self-organizing maps (FlowSOM) algorithms. As a result, the ASGR1⁺CD130⁺Annexin V⁺ EP subpopulation exhibited the highest accuracy for predicting ACR (area under the curve: 0.80, 95% confidence interval [CI], 0.70-0.90), with diagnostic sensitivity and specificity of 100% (95% CI, 81.67-100.0%) and 68.5% (95% CI, 55.3-79.3%), respectively. In summary, this new EP subpopulation presented the highest diagnostic accuracy for detecting ACR in LT patients.

Liver Resection Promotes (Regulates) Proinflammatory Cytokines in Patients with Hepatocellular Carcinoma

BACKGROUND

Several animal studies have shown the roles of cytokines in regulating liver regeneration following liver resection (LR), which is a type of surgery designed to remove cancerous tumors from the liver. This study investigated how the expressions and serum levels of some pro- and anti-inflammatory cytokines in patients with hepatocellular carcinoma (HCC) were changed during LR.

METHODS

Liver tissues from 15 patients with HCC were collected and the levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), IL-1α, IL-1 β, IL-10, and transforming growth factor-beta1 (TGF-β1) were assessed using real-time PCR assay at different times before and after LR. The serum values of TNF-α and IL-6 were also measured by ELISA.

RESULTS

After 60 and 90 minutes of LR, IL-6 gene expression was significantly increased (P < 0.001 - 0.05). The same trend was also observed in TNF-α expression after 90 minutes of LR (P < 0.01). No significant changes were observed in the expressions of IL-1α, IL-1β, IL-10, and TGF-β1 before and after LR. In addition, LR had significant effects on TNF-α and IL-6 serum levels (P < 0.05 - 0.0001).

CONCLUSION

Our data provided further evidence to reveal that IL-6 and TNF-α cytokines are critical to improve liver regeneration.

Recipient interleukin 6 gene polymorphism and expression predict HCV recurrence post liver transplantation

BACKGROUND

Liver transplantation (LTX)is a lifesaving- effective protocol for patients suffering end stage liver disease (ESLD) and its complications post HCV infection. Recurrence of disease is a frequent clinical complication that is observed in patients undergoing LTX. Cytokines play a central role in the immunological events occurring after the surgery.

METHODS

Using Allelic Discrimination PCR, the allelic variation G174C of IL-6 gene was investigated. The abundance of IL6- mRNA and plasma IL6 cytokine levels were evaluated by using qRT-PCR in peripheral blood mononuclear cells (PBMCs) and enzyme-linked immunosorbent assay (ELISA) respectively in 76 liver transplant recipients recruited from Al Sahel teaching hospital, Ministry of Health and Population Cairo Egypt within the period between June 2015 and October 2017.

RESULTS

The frequencies of IL-6 GG genotype and the G allele were significantly detected more in LTX recipients who experienced HCV recurrence versus those who did not suffer recurrence when compared to healthy controls (P = 0.001) and (P = 0.006), respectively. On the contrary, levels of IL-6 related transcripts in PBMC's of recurrent patients were indifferent from non-recurrent patients and healthy controls (P ≥ 0.124). Interestingly, the circulating IL-6 protein in plasma was significantly elevated in recurrent as compared to the non-recurrent recipients (P = 0.002).

CONCLUSION

HCV recurrence post liver transplantation occur more frequently in patients with -174 G/G IL-6 genotype and elevated plasma IL-6 levels.

Tocilizumab in transplantation

PURPOSE

Tocilizumab, a monoclonal antibody directed against the IL-6 receptor, might block detrimental effects of IL-6 on transplantation. IL-6 plays a considerable role in cytokine storm after stem cell transplantation as well as graft versus host disease, and it has also been shown to be involved in solid organ allograft rejection; therefore, tocilizumab is expected to promote graft survival. Nonetheless, due to the small number of studies and disparate methods of drug administration and outcome evaluation, for which types of transplantation, at which stages, and to what extent tocilizumab could be applied remains to be defined.

METHODS

The Pubmed, SCOPUS and Google Scholar search engines were used to collect data. The keywords were determined by Pubmed MeSH. No time limitation was set and all types of articles were allowed.  RESULTS: According to the potential of Tocilozumab in controlling both cellular and humoral immunity it could be considered as a promising agent in tolerance induction; however, blocking IL-6 signaling might result in augmented infection rate in recipients.

CONCLUSION

The need for providing effective and safe immunosuppressive agents to protect transplanted cells and organs against allo-reactivity urges the collection and discussion of all available findings about inhibition of determining immune components including cytokines; herein, we have summarized the clinical consequences of blocking IL-6 by tocilizumab in stem cell and solid organ transplantations.

Markers of liver regeneration-the role of growth factors and cytokines: a systematic review

BACKGROUND

Post-hepatectomy liver failure contributes significantly to postoperative mortality after liver resection. The prediction of the individual risk for liver failure is challenging. This review aimed to provide an overview of cytokine and growth factor triggered signaling pathways involved in liver regeneration after resection.

METHODS

MEDLINE and Cochrane databases were searched without language restrictions for articles from the time of inception of the databases till March 2019. All studies with comparative data on the effect of cytokines and growth factors on liver regeneration in animals and humans were included.

RESULTS

Overall 3.353 articles comprising 40 studies involving 1.498 patients and 101 animal studies were identified and met the inclusion criteria. All included trials on humans were retrospective cohort/observational studies. There was substantial heterogeneity across all included studies with respect to the analyzed cytokines and growth factors and the described endpoints.

CONCLUSION

High-level evidence on serial measurements of growth factors and cytokines in blood samples used to predict liver regeneration after resection is still lacking. To address the heterogeneity of patients and potential markers, high throughput serial analyses may offer a method to predict an individual's regenerative potential in the future.

Serum Tumor Necrosis Factor-α Is Inversely Associated With the Psoas Muscle Index in Both Male and Female Patients Scheduled for Living Donor Liver Transplantation

BACKGROUND

Patients on a waiting list for liver transplantation frequently show core muscle wasting, referred to as sarcopenia, which results in poor prognosis. To date, there has been a lack of research on the association between inflammation mediators, including cytokines, and loss of core muscle mass in cirrhotic patients scheduled for living donor liver transplantation (LDLT).

METHODS

Cytokines in serum, such as interleukin (IL)-2, IL-6, IL-10, IL-12, IL-17, interferon-γ, and tumor necrosis factor (TNF)-α, were retrospectively investigated in 234 LDLT patients 1 day before surgery. The psoas muscle area was measured using abdominal computed tomography within 1 month before surgery and used to calculate the psoas muscle index (PMI = psoas muscle area/height²). The study population was classified into 2 groups according to the interquartile range of PMI: a non-sarcopenia group (> 25th quartile) and a sarcopenia group (≤ 25th quartile) in each sex.

RESULTS

In both sexes, IL-10 and TNF-α levels were significantly higher in the sarcopenia group than the non-sarcopenia group. In a univariate analysis, male patients showed that serum IL-10 and TNF-α levels were potentially associated with sarcopenia. Serum TNF-α was independently associated with sarcopenia in a multivariate analysis. In female patients, TNF-α was significantly associated with sarcopenia in both univariate and multivariate analyses. Male patients with a PMI ≤ 25th quartile had significantly higher TNF-α levels than those in other quartile ranges, and female patients with a PMI ≤ 25th quartile had a significantly higher TNF-α level than those with a PMI > 75th quartile.

CONCLUSIONS

Serum levels of TNF-α are inversely associated with skeletal muscle wasting in both male and female patients scheduled for LDLT.

Mesenchymal Stem Cells Improve Glycometabolism and Liver Regeneration in the Treatment of Post-hepatectomy Liver Failure

Background

The mortality rate of post-hepatectomy liver failure (PHLF) remains very high, and liver transplantation is the only effective treatment regimen for PHLF. Cell transplantation is a potential treatment for liver diseases. Previous studies have proved that mesenchymal stem cells (MSCs) have immunomodulatory functions. In the present study, we found that MSCs promoted glycogen synthesis and liver regeneration in the treatment of PHLF. MSC transplantation also improved the survival rate of rats after 90% partial hepatectomy (PH). In our current study, we aimed to determine the efficacy and mechanism of MSC transplantation in the treatment of PHLF.

Methods

Mesenchymal stem cells were isolated from Sprague-Dawley rats and cultured using a standardized protocol. The MSCs were transplanted to treat acute liver failure induced by 90% PH. The therapeutic efficacy of MSCs on PHLF was verified through measuring alanine transaminase (ALT), aspartate aminotransferase (AST), international normalized ratio (INR), serum ammonia, liver weight to body weight ratio, blood glucose, and histology. To further study the mechanism of MSC transplantation in treatment for PHLF, we assessed the changes in the AKT/glycogen synthase kinase-3β (GSK-3β)/β-catenin pathway. A-674563 (AKT inhibitor) and SB216763 (GSK-3β inhibitor) were employed to validate our findings. SPSS version 19.0 was used for statistical analysis, and the independent-samples t-test was carried out to analyze the collected data.

Results

Mesenchymal stem cell transplantation attenuated the liver injury in acute liver failure induced by 90% PH. MSC transplantation improved the glucose metabolism and survival rate in the PHLF model. The effect of MSC transplantation on hepatocyte proliferation might be related to AKT/GSK-3β/β-catenin pathway.

Conclusion

Mesenchymal stem cell transplantation could be use as a potential treatment for PHLF.

Cytokine Profiles Associated With Angiotensin II Type 1 Receptor Antibodies

Introduction

Angiotensin II type 1 receptor antibody (AT1R-Ab), is a non–human leukocyte antigen (HLA) antibody implicated in poor renal allograft outcomes, although its actions may be mediated through a different pathway than HLA donor-specific antibodies (DSAs). Our aim was to examine serum cytokine profiles associated with AT1R-Ab and distinguish them from those associated with HLA DSA in serially collected blood samples from a cohort of pediatric renal transplant recipients.

Methods

Blood samples from 65 pediatric renal transplant recipients drawn during the first 3 months posttransplant, at 6, 12, and 24 months posttransplant, and during suspected episodes of kidney transplant rejection were tested for AT1R-Ab, HLA DSA, and a panel of 6 cytokines (tumor necrosis factor [TNF]-α, interferon [IFN]-γ, interleukin [IL]-8, IL-1β, IL-6, and IL-17). Associations between antibodies and cytokines were evaluated.

Results

AT1R-Ab, but not HLA DSA, was associated with elevations in TNF-α, IFN-γ, IL-8, IL-1β, IL-6, and IL-17. This relationship remained significant even after controlling for relevant clinical factors and was consistent across all time points. In contrast to HLA DSA, AT1R-Ab was associated with elevations in vascular inflammatory cytokines in the first 2 years posttransplant.

Conclusions

This profile of vascular cytokines may be informative for clinical monitoring and designing future studies to delineate the distinct pathophysiology of AT1R-Ab–mediated allograft injury in kidney transplantation.

Portal venous velocity affects liver regeneration after right lobe living donor hepatectomy

OBJECTIVES

We investigated whether chronological changes in portal flow and clinical factors play a role in the liver regeneration (LR) process after right donor-hepatectomy.

MATERIALS AND METHODS

Participants in this prospective study comprised 58 donors who underwent right donor-hepatectomy during the period February 2014 to February 2015 at a single medical institution. LR was estimated using two equations: remnant left liver (RLL) growth (%) and liver volumetric recovery (LVR) (%). Donors were classified into an excellent regeneration (ER) group or a moderate regeneration (MR) group based on how their LR on postoperative day 7 compared to the median value.

RESULTS

Multivariate analysis revealed that low residual liver volume (OR = .569, 95% CI: .367- .882) and high portal venous velocity in the immediate postoperative period (OR = 1.220, 95% CI: 1.001-1.488) were significant predictors of LR using the RLL growth equation; high portal venous velocity in the immediate postoperative period (OR = 1.325, 95% CI: 1.081-1.622) was a significant predictor of LR using the LVR equation. Based on the two equations, long-term LR was significantly greater in the ER group than in the MR group (p < .001).

CONCLUSION

Portal venous velocity in the immediate postoperative period was an important factor in LR. The critical time for short-term LR is postoperative day 7; it is associated with long-term LR in donor-hepatectomy.