Retinal metabolism displays evidence for uncoupling of glycolysis and oxidative phosphorylation via Cori-, Cahill-, and mini-Krebs-cycle.

The retina consumes massive amounts of energy, yet its metabolism and substrate exploitation remain poorly understood. Here, we used a murine explant model to manipulate retinal energy metabolism under entirely controlled conditions and utilised 1H-NMR spectroscopy-based metabolomics, in situ enzyme detection, and cell viability readouts to uncover the pathways of retinal energy production. Our experimental manipulations resulted in varying degrees of photoreceptor degeneration, while the inner retina and retinal pigment epithelium were essentially unaffected. This selective vulnerability of photoreceptors suggested very specific adaptations in their energy metabolism. Rod photoreceptors were found to rely strongly on oxidative phosphorylation, but only mildly on glycolysis. Conversely, cone photoreceptors were dependent on glycolysis but insensitive to electron transport chain decoupling. Importantly, photoreceptors appeared to uncouple glycolytic and Krebs-cycle metabolism via three different pathways: (1) the mini-Krebs-cycle, fuelled by glutamine and branched chain amino acids, generating N-acetylaspartate; (2) the alanine-generating Cahill-cycle; (3) the lactate-releasing Cori-cycle. Moreover, the metabolomics data indicated a shuttling of taurine and hypotaurine between the retinal pigment epithelium and photoreceptors, likely resulting in an additional net transfer of reducing power to photoreceptors. These findings expand our understanding of retinal physiology and pathology and shed new light on neuronal energy homeostasis and the pathogenesis of neurodegenerative diseases.

Predictive role of hepatic venous pressure gradient in bleeding events among patients with cirrhosis undergoing orthotopic liver transplantation.

Background & Aims: Major bleeding events during orthotopic liver transplantation (OLT) are associated with poor outcomes. The proportion of this risk related to portal hypertension is unclear. Hepatic venous pressure gradient (HVPG) is the gold standard for estimating portal hypertension. The aim of this study was to analyze the ability of HVPG to predict intraoperative major bleeding events during OLT in patients with cirrhosis. Methods: We retrospectively analyzed a prospective database including all patients with cirrhosis who underwent OLT between 2010 and 2020 and had liver and right heart catheterizations as part of their pre-transplant assessment. The primary endpoint was the occurrence of an intraoperative major bleeding event. Results: The 468 included patients had a median HVPG of 17 mmHg [interquartile range, 13-22] and a median MELD on the day of OLT of 16 [11-24]. Intraoperative red blood cell transfusion was required in 72% of the patients (median 2 units transfused), with a median blood loss of 1,000 ml [575-1,500]. Major intraoperative bleeding occurred in 156 patients (33%) and was associated with HVPG, preoperative hemoglobin level, severity of cirrhosis at the time of OLT (MELD score, ascites, encephalopathy), hemostasis impairment (thrombocytopenia, lower fibrinogen levels), and complications of cirrhosis (sepsis, acute-on-chronic liver failure). By multivariable regression analysis with backward elimination, HVPG, preoperative hemoglobin level, MELD score, and tranexamic acid infusion were associated with the primary endpoint. Three categories of patients were identified according to HVPG: low-risk (HVPG <16 mmHg), high-risk (HVGP ≥16 mmHg), and very high-risk (HVPG ≥20 mmHg). Conclusions: HVPG predicted major bleeding events in patients with cirrhosis undergoing OLT. Including HVPG as part of pre-transplant assessment might enable better anticipation of the intraoperative course. Impact and implications: Major bleeding events during orthotopic liver transplantation (OLT) are associated with poor outcomes but the proportion of this risk related to portal hypertension is unclear. Our work shows that hepatic venous pressure gradient (HVPG), the gold standard for estimating portal hypertension, is a strong predictor of major bleeding events and blood loss volume in patients with cirrhosis undergoing OLT. Three groups of patients can be identified according to their risk of major bleeding events: low-risk patients with HVPG <16 mmHg, high-risk patients with HVPG ≥16 mmHg, and very high-risk patients with HVPG ≥20 mmHg. HVPG could be systematically included in the pre-transplant assessment to anticipate intraoperative course and tailor patient management.

Upfront multi-bipolar radiofrequency ablation for HCC in transplant-eligible cirrhotic patients with salvage transplantation in case of recurrence.

INTRODUCTION: We aim to assess the long-term outcomes of percutaneous multi-bipolar radiofrequency (mbpRFA) as the first treatment for hepatocellular carcinoma (HCC) in transplant-eligible cirrhotic patients, followed by salvage transplantation for intrahepatic distant tumour recurrence or liver failure. MATERIALS AND METHODS: We included transplant-eligible patients with cirrhosis and a first diagnosis of HCC within Milan criteria treated by upfront mbp RFA. Transplantability was defined by age <70 years, social support, absence of significant comorbidities, no active alcohol use and no recent extrahepatic cancer. Baseline variables were correlated with outcomes using the Kaplan-Meier and Cox models. RESULTS: Among 435 patients with HCC, 172 were considered as transplantable with HCCs >2 cm (53%), uninodular (87%) and AFP >100 ng/mL (13%). Median overall survival was 87 months, with 75% of patients alive at 3 years, 61% at 5 years and 43% at 10 years. Age (p = .003) and MELD>10 (p = .01) were associated with the risk of death. Recurrence occurred in 118 patients within Milan criteria in 81% of cases. Local recurrence was observed in 24.5% of cases at 10 years and distant recurrence rates were observed in 69% at 10 years. After local recurrence, 69% of patients were still alive at 10 years. At the first tumour recurrence, 75 patients (65%) were considered transplantable. Forty-one patients underwent transplantation, mainly for distant intrahepatic tumour recurrence. The overall 5-year survival post-transplantation was 72%, with a tumour recurrence of 2.4%. CONCLUSION: Upfront multi-bipolar RFA for a first diagnosis of early HCC on cirrhosis coupled with salvage liver transplantation had a favourable intention-to-treat long-term prognosis, allowing for spare grafts.

Clinical, experimental and pathophysiological effects of Yaq-001: a non-absorbable, gut-restricted adsorbent in models and patients with cirrhosis.

OBJECTIVE: Targeting bacterial translocation in cirrhosis is limited to antibiotics with risk of antimicrobial resistance. This study explored the therapeutic potential of a non-absorbable, gut-restricted, engineered carbon bead adsorbent, Yaq-001 in models of cirrhosis and acute-on-chronic liver failure (ACLF) and, its safety and tolerability in a clinical trial in cirrhosis. DESIGN: Performance of Yaq-001 was evaluated in vitro. Two-rat models of cirrhosis and ACLF, (4 weeks, bile duct ligation with or without lipopolysaccharide), receiving Yaq-001 for 2 weeks; and two-mouse models of cirrhosis (6-week and 12-week carbon tetrachloride (CCl4)) receiving Yaq-001 for 6 weeks were studied. Organ and immune function, gut permeability, transcriptomics, microbiome composition and metabolomics were analysed. The effect of faecal water on gut permeability from animal models was evaluated on intestinal organoids. A multicentre, double-blind, randomised, placebo-controlled clinical trial in 28 patients with cirrhosis, administered 4 gr/day Yaq-001 for 3 months was performed. RESULTS: Yaq-001 exhibited rapid adsorption kinetics for endotoxin. In vivo, Yaq-001 reduced liver injury, progression of fibrosis, portal hypertension, renal dysfunction and mortality of ACLF animals significantly. Significant impact on severity of endotoxaemia, hyperammonaemia, liver cell death, systemic inflammation and organ transcriptomics with variable modulation of inflammation, cell death and senescence in the liver, kidneys, brain and colon was observed. Yaq-001 reduced gut permeability in the organoids and impacted positively on the microbiome composition and metabolism. Yaq-001 regulated as a device met its primary endpoint of safety and tolerability in the clinical trial. CONCLUSIONS: This study provides strong preclinical rationale and safety in patients with cirrhosis to allow clinical translation. TRIAL REGISTRATION NUMBER: NCT03202498.

Integrative Kinase Activity Profiling and Phosphoproteomics of rd10 Mouse Retina during cGMP-Dependent Retinal Degeneration.

Inherited retinal degenerative diseases (IRDs) are a group of rare diseases that lead to a progressive loss of photoreceptor cells and, ultimately, blindness. The overactivation of cGMP-dependent protein kinase G (PKG), one of the key effectors of cGMP-signaling, was previously found to be involved in photoreceptor cell death and was studied in murine IRD models to elucidate the pathophysiology of retinal degeneration. However, PKG is a serine/threonine kinase (STK) with several hundred potential phosphorylation targets and, so far, little is known about the specificity of the target interaction and downstream effects of PKG activation. Here, we carried out both the kinome activity and phosphoproteomic profiling of organotypic retinal explant cultures derived from the rd10 mouse model for IRD. After treating the explants with the PKG inhibitor CN03, an overall decrease in peptide phosphorylation was observed, with the most significant decrease occurring in seven peptides, including those from the known PKG substrate cyclic-AMP-response-element-binding CREB, but also Ca2+/calmodulin-dependent kinase (CaMK) peptides and TOP2A. The phosphoproteomic data, in turn, revealed proteins with decreased phosphorylation, as well as proteins with increased phosphorylation. The integration of both datasets identified common biological networks altered by PKG inhibition, which included kinases predominantly from the so-called AGC and CaMK families of kinases (e.g., PKG1, PKG2, PKA, CaMKs, RSKs, and AKTs). A pathway analysis confirmed the role of CREB, Calmodulin, mitogen-activated protein kinase (MAPK) and CREB modulation. Among the peptides and pathways that showed reduced phosphorylation activity, the substrates CREB, CaMK2, and CaMK4 were validated for their retinal localization and activity, using immunostaining and immunoblotting in the rd10 retina. In summary, the integrative analysis of the kinome activity and phosphoproteomic data revealed both known and novel PKG substrates in a murine IRD model. This data establishes a basis for an improved understanding of the biological pathways involved in cGMP-mediated photoreceptor degeneration. Moreover, validated PKG targets like CREB and CaMKs merit exploration as novel (surrogate) biomarkers to determine the effects of a clinical PKG-targeted treatment for IRDs.

Acute kidney injury in patients with cirrhosis: Acute Disease Quality Initiative (ADQI) and International Club of Ascites (ICA) joint multidisciplinary consensus meeting.

Patients with cirrhosis are prone to developing acute kidney injury (AKI), a complication associated with a markedly increased in-hospital morbidity and mortality, along with a risk of progression to chronic kidney disease. Whereas patients with cirrhosis are at increased risk of developing any phenotype of AKI, hepatorenal syndrome (HRS), a specific form of AKI (HRS-AKI) in patients with advanced cirrhosis and ascites, carries an especially high mortality risk. Early recognition of HRS-AKI is crucial since administration of splanchnic vasoconstrictors may reverse the AKI and serve as a bridge to liver transplantation, the only curative option. In 2023, a joint meeting of the International Club of Ascites (ICA) and the Acute Disease Quality Initiative (ADQI) was convened to develop new diagnostic criteria for HRS-AKI, to provide graded recommendations for the work-up, management and post-discharge follow-up of patients with cirrhosis and AKI, and to highlight priorities for further research.

Extracellular lactate as an alternative energy source for retinal bipolar cells.

Retinal bipolar and amacrine cells receive visual information from photoreceptors and participate in the first steps of image processing in the retina. Several studies have suggested the operation of aerobic glycolysis and a lactate shuttle system in the retina due to the high production of this metabolite under aerobic conditions. However, whether bipolar cells form part of this metabolic circuit remains unclear. Here, we show that the monocarboxylate transporter 2 is expressed and functional in inner retinal neurons. Additionally, we used genetically encoded FRET nanosensors to demonstrate the ability of inner retinal neurons to consume extracellular lactate as an alternative to glucose. In rod bipolar cells, lactate consumption allowed cells to maintain the homeostasis of ions and electrical responses. We also found that lactate synthesis and transporter inhibition caused functional alterations and an increased rate of cell death. Overall, our data shed light on a notable but still poorly understood aspect of retinal metabolism.

T-type voltage-gated channels, Na+/Ca2+-exchanger, and calpain-2 promote photoreceptor cell death in inherited retinal degeneration.

Inherited retinal degenerations (IRDs) are a group of untreatable and commonly blinding diseases characterized by progressive photoreceptor loss. IRD pathology has been linked to an excessive activation of cyclic nucleotide-gated channels (CNGC) leading to Na+- and Ca2+-influx, subsequent activation of voltage-gated Ca2+-channels (VGCC), and further Ca2+ influx. However, a connection between excessive Ca2+ influx and photoreceptor loss has yet to be proven.Here, we used whole-retina and single-cell RNA-sequencing to compare gene expression between the rd1 mouse model for IRD and wild-type (wt) mice. Differentially expressed genes indicated links to several Ca2+-signalling related pathways. To explore these, rd1 and wt organotypic retinal explant cultures were treated with the intracellular Ca2+-chelator BAPTA-AM or inhibitors of different Ca2+-permeable channels, including CNGC, L-type VGCC, T-type VGCC, Ca2+-release-activated channel (CRAC), and Na+/Ca2+ exchanger (NCX). Moreover, we employed the novel compound NA-184 to selectively inhibit the Ca2+-dependent protease calpain-2. Effects on the retinal activity of poly(ADP-ribose) polymerase (PARP), sirtuin-type histone-deacetylase, calpains, as well as on activation of calpain-1, and - 2 were monitored, cell death was assessed via the TUNEL assay.While rd1 photoreceptor cell death was reduced by BAPTA-AM, Ca2+-channel blockers had divergent effects: While inhibition of T-type VGCC and NCX promoted survival, blocking CNGCs and CRACs did not. The treatment-related activity patterns of calpains and PARPs corresponded to the extent of cell death. Remarkably, sirtuin activity and calpain-1 activation were linked to photoreceptor protection, while calpain-2 activity was related to degeneration. In support of this finding, the calpain-2 inhibitor NA-184 protected rd1 photoreceptors.These results suggest that Ca2+ overload in rd1 photoreceptors may be triggered by T-type VGCCs and NCX. High Ca2+-levels likely suppress protective activity of calpain-1 and promote retinal degeneration via activation of calpain-2. Overall, our study details the complexity of Ca2+-signalling in photoreceptors and emphasizes the importance of targeting degenerative processes specifically to achieve a therapeutic benefit for IRDs. Video Abstract.

Use of genotypic HIV DNA testing: a DELPHI-type consensus.

OBJECTIVES: As many disparities in the clinical use of HIV DNA sequencing are observed, a DELPHI-type consensus was initiated in France to homogenize use, techniques and interpretation of results. METHODS: Based on a literature review and clinical experience, a steering committee (SC) of eight virologists and one infectious disease specialist formulated statements. Statements were submitted to an independent and anonymous electronic vote of virologists and HIV clinicians in France, between October 2022 and December 2022. RESULTS: The SC developed 20 statements grouped into six categories: clinical situations for the use of HIV DNA genotyping; techniques for performing HIV DNA genotyping; consideration of apolipoprotein B mRNA editing enzyme (APOBEC) mutations; genotyping results reporting; recycling of antiretrovirals; and availability of HIV DNA genotyping tests and delays. Twenty-one virologists and 47 clinicians participated in two voting rounds and 18/20 (90%) assertions reached a 'strong' consensus. For example, that prior genotyping on HIV DNA is useful for clinical decision-making when considering switching to some long-acting regimens or to reduce the number of antiretroviral agents in virologically suppressed patients for whom RNA data are unavailable/not exploitable/not sufficiently informative. Two statements achieved no consensus: reporting any detected viral minority population for discussion in multidisciplinary meetings (virologists), and possible risk of virological failure when using a second-generation InSTI plus lamivudine or emtricitabine regimen in patients with undetectable viral load within ≥1 year and in the presence of a documented M184V mutation within the last 5 years (clinicians). CONCLUSIONS: This DELPHI-type consensus will facilitate the strengthening and harmonization of good practice when performing HIV DNA sequencing.

Autoimmune hepatitis recurrence after liver transplantation: "Les jeux sont faits".

Autoimmune hepatitis (AIH) may recur after liver transplantation (LT). The aims of this study were to evaluate the incidence and risk factors for recurrent autoimmune hepatitis (rAIH). A multicenter retrospective French nationwide study, including all patients aged ≥16 transplanted for AIH, with at least 1 liver biopsy 1 year after LT, was conducted between 1985 and 2018. Risk factors for rAIH were identified using a multivariate Cox regression model. Three hundred and forty-four patients were included (78.8% women) with a median age at LT of 43.6 years. Seventy-six patients (22.1%) developed recurrence in a median time of 53.6 months (IQR, 14.1-93.2). Actuarial risk for developing rAIH was 41.3% 20 years after LT. In multivariate analysis, the strongest risk factor for rAIH was cytomegalovirus D+/R- mismatch status (HR=2.0; 95% CI: 1.1-3.6; p =0.03), followed by associated autoimmune condition. Twenty-one patients (27.6% of rAIH patients) developed liver graft cirrhosis after rAIH. Independent risk factors for these severe forms of rAIH were young age at LT, IgG levels >20.7 g/L, and LT in the context of (sub)fulminant hepatitis. Immunosuppression, especially long-term maintenance of corticosteroid therapy, was not significantly associated with rAIH. Recurrence of AIH after LT is frequent and may lead to graft loss. Recurrence is more frequent in young patients with active disease at the time of LT, yet systematic corticosteroid therapy does not prevent it.

Osteoporosis and Fragility Fractures in Patients With Cirrhosis Evaluated for Liver Transplantation: Identification of High-Risk Patients Based on Computed Tomography at Evaluation.

INTRODUCTION: Osteoporosis in candidates for liver transplantation (LT) is often underdiagnosed despite the important consequences of morbidity. METHODS: We included 376 patients with cirrhosis evaluated for LT with available computed tomography (CT) scans. Prevalent vertebral fractures (VFs) were identified on CT reconstructions, and bone density was assessed by measuring CT attenuation of the L1 vertebra (L1-CT). RESULTS: We identified 139 VFs in 55 patients (14.6%). Logistic regression models showed that low L1-CT was the only independent determinant of VF. DISCUSSION: In patients with cirrhosis evaluated for LT, CT scans identified persons with severe osteoporosis without additional costs.

Determinants of clinical response to empirical antibiotic treatment in patients with cirrhosis and bacterial and fungal infections-Results from the ICA "Global Study" (EABCIR-Global Study).

BACKGROUND: The administration of an appropriate empirical antibiotic treatment is essential in cirrhosis and severe bacterial infections. We aimed to investigate the predictors of clinical response of empirical antibiotic treatment in a prospective cohort of patients with cirrhosis and bacterial and fungal infections included in the International Club of Ascites "Global Study." METHODS: Patients hospitalized with cirrhosis and bacterial/fungal infection were prospectively enrolled at 46 centers. Clinical response to antibiotic treatment was defined according to changes in markers of infection/inflammation, vital signs, improvement of organ failure, and results of cultures. RESULTS: From October 2015 to September 2016, 1302 patients were included at 46 centers. A clinical response was achieved in only 61% of cases. Independent predictors of lack of clinical response to empirical treatment were C-reactive protein (OR = 1.16; 95% CI = 1.02-1.31), blood leukocyte count (OR = 1.39;95% CI = 1.09-1.77), serum albumin (OR = 0.70; 95% CI = 0.55-0.88), nosocomial infections (OR = 1.96; 95% CI = 1.20-2.38), pneumonia (OR = 1.75; 95% CI = 1.22-2.53), and ineffective treatment according to antibiotic susceptibility test (OR = 5.32; 95% CI = 3.47-8.57). Patients with a lack of clinical response to first-line antibiotic treatment had a significantly lower resolution rate of infections (55% vs. 96%; p < 0.001), a higher incidence of second infections (29% vs. 15%; p < 0.001), shock (35% vs. 7%; p < 0.001) and new organ failures (52% vs. 19 %; p < 0.001) than responders. Clinical response to empirical treatment was an independent predictor of 28-day survival ( subdistribution = 0.20; 95% CI = 0.14-0.27). CONCLUSIONS: Four out of 10 patients with cirrhosis do not respond to the first-line antibiotic therapy, leading to lower resolution of infections and higher mortality. Broader-spectrum antibiotics and strategies targeting systemic inflammation may improve prognosis in patients with a high degree of inflammation, low serum albumin levels, and severe liver impairment.

Identification of liver transplant biopsy phenotypes associated with distinct liver biological markers and allograft survival.

The intricate association between histologic lesions and circulating antihuman leucocyte antigen donor-specific antibodies (DSA) in liver transplantation (LT) requires further clarification. We conducted a probabilistic, unsupervised approach in a comprehensively well-annotated LT cohort to identify clinically relevant archetypes. We evaluated 490 pairs of LT biopsies with DSA testing from 325 recipients transplanted between 2010 and 2020 across 3 French centers and an external cohort of 202 biopsies from 128 recipients. Unsupervised archetypal analysis integrated all clinico-immuno-histologic parameters of each biopsy to identify biopsy archetypes. The median time after LT was 1.17 (interquartile range, 0.38-2.38) years. We identified 7 archetypes distinguished by clinico-immuno-histologic parameters: archetype #1: severe T cell-mediated rejection (15.9%); #2: chronic rejection with ductopenia (1.8%); #3: architectural and microvascular damages (3.5%); #4: (sub)normal (55.9%); #5: mild T cell-mediated rejection (4.9%); #6: acute antibody-mediated rejection (6.5%); and #7: chronic rejection with DSA (11.4%). Cell infiltrates vary in the archetype. These archetypes were associated with distinct liver biological markers and allograft outcomes. These findings remained consistent when stratified using the patient's age or indications for LT, with good performance in the external cohort (mean highest probability assignment = 0.58, standard deviation ± 0.17). In conclusion, we have identified clinically meaningful archetypes, providing valuable insights into the intricate DSA-histology association, which may help standardize liver allograft pathology classification.

The screening and management of sleep disturbances in people living with HIV: Delphi consensus.

Sleep disturbances in people living with HIV (PLHIV) are frequent but their management remains insufficient. In the absence of specific recommendations, a DELPHI consensus research project was conducted in France to establish best practice. A multidisciplinary Steering Committee (STC) undertook a literature review and used it with clinical expertise to create statements that were voted on. Two profiles of healthcare professionals with significant experience in monitoring PLHIV were selected for the voting: physicians and nurses/psychologists. Votes were collected electronically, independently, and anonymously. The STC created 27 statements covering six areas: Screening of sleep disturbances, Investigation, First-line management, Referral to a specialist, Antiretroviral treatment (ARV), and Prevention. Two rounds of votes included 42 physicians and 32 nurses/psychologists. Consensus was reached for 24 out of 27 statements (89%) including: to assess quantity and quality of sleep among PLHIV at least annually, ideally using a common methodology within the medical department; to consider the temporary addition of a hypnotic treatment in cases of acute insomnia not improved by the rules of sleep hygiene, with full awareness of potential drug-drug interactions and risk of dependence; to correct ferritinaemia if <100 ng/mL before referral to a specialist when restless legs syndrome is suspected; to consider changing the time of ARV administration or an ARV switch within the same class when sleep disturbances are caused by an ARV. This DELPHI Consensus provides best practice for screening and managing sleep disturbances in PLHIV and optimising their quality of life.

Liver disease in germline mutations of telomere-related genes: Prevalence, clinical, radiological, pathological features, outcome, and risk factors.

BACKGROUND AND AIM: Germline mutations of telomere-related genes (TRG) induce multiorgan dysfunction, and liver-specific manifestations have not been clearly outlined. We aimed to describe TRG mutations-associated liver diseases. APPROACH AND RESULTS: Retrospective multicenter analysis of liver disease (transaminases > 30 IU/L and/or abnormal liver imaging) in patients with TRG mutations. Main measurements were characteristics, outcomes, and risk factors of liver disease in a TRG mutations cohort. The prevalence of liver disease was compared to a community-based control group (n = 1190) stratified for age and matched 1:3 for known risk factors of liver disease. Among 132 patients with TRG mutations, 95 (72%) had liver disease, with associated lung, blood, skin, rheumatological, and ophthalmological TRG diseases in 82%, 77%, 55%, 39%, and 30% of cases, respectively. Liver biopsy was performed in 52/95 patients, identifying porto-sinusoidal vascular disease in 48% and advanced fibrosis/cirrhosis in 15%. After a follow-up of 21 months (12-54), ascites, hepato-pulmonary syndrome, variceal bleeding, and HCC occurred in 14%, 13%, 13%, and 2% of cases, respectively. Five-year liver transplantation-free survival was 69%. A FIB-4 score ≥ 3·25 and ≥1 risk factor for cirrhosis were associated with poor liver transplantation-free survival. Liver disease was more frequent in patients with TRG mutations than in the paired control group [80/396, (20%)], OR 12.9 (CI 95%: 7.8-21.3, p < 0.001). CONCLUSIONS: TRG mutations significantly increase the risk of developing liver disease. Although symptoms may be mild, they may be associated with severe disease. Porto-sinusoidal vascular disease and cirrhosis were the most frequent lesions, suggesting that the mechanism of action is multifactorial.

Novel prognostic biomarkers in decompensated cirrhosis: a systematic review and meta-analysis.

BACKGROUND: Patients with decompensated cirrhosis experience high mortality rates. Current prognostic scores, including the model for end-stage liver disease (MELD), may underperform in settings other than in those they were initially developed. Novel biomarkers have been proposed to improve prognostication accuracy and even to predict development of complications. METHODS: We performed a systematic review and meta-analysis on novel urine and blood biomarkers and their ability to predict 90-day mortality in patients with decompensated cirrhosis. Secondary outcomes included 28-day and 1-year mortality, and development of acute-on-chronic liver failure, acute kidney injury and other complications. To overcome differences in units, temporal changes in assays and reporting heterogeneity, we used the ratio of means (RoM) as measure of association for assessing strength in predicting outcomes. An RoM>1 implies that the mean biomarker level is higher in those that develop the outcome than in those that do not. RESULTS: Of 6629 unique references, 103 were included, reporting on 29 different biomarkers, with a total of 31 362 biomarker patients. Most studies were prospective cohorts of hospitalised patients (median Child-Pugh-Turcotte score of 9 and MELD score of 18). The pooled 90-day mortality rate was 0.27 (95% CI 0.24 to 0.29). The RoM for predicting 90-day mortality was highest for interleukin 6 (IL-6) (2.56, 95% CI 2.39 to 2.74), followed by urinary neutrophil gelatinase-associated lipocalin (uNGAL) (2.42, 95% CI 2.20 to 2.66) and copeptin (2.33, 95% CI 2.17 to 2.50). These RoMs were all higher than for MELD (1.44, 95% CI 1.42 to 1.46). CONCLUSION: Novel biomarkers, including IL-6, uNGAL and copeptin, can probably improve prognostication of patients with decompensated cirrhosis compared with MELD alone.

The PKG Inhibitor CN238 Affords Functional Protection of Photoreceptors and Ganglion Cells against Retinal Degeneration.

Hereditary retinal degeneration (RD) is often associated with excessive cGMP signalling in photoreceptors. Previous research has shown that inhibition of cGMP-dependent protein kinase G (PKG) can reduce photoreceptor loss in two different RD animal models. In this study, we identified a PKG inhibitor, the cGMP analogue CN238, which preserved photoreceptor viability and functionality in rd1 and rd10 mutant mice. Surprisingly, in explanted retinae, CN238 also protected retinal ganglion cells from axotomy-induced retrograde degeneration and preserved their functionality. Furthermore, kinase activity-dependent protein phosphorylation of the PKG target Kv1.6 was reduced in CN238-treated rd10 retinal explants. Ca2+-imaging on rd10 acute retinal explants revealed delayed retinal ganglion cell repolarization with CN238 treatment, suggesting a PKG-dependent modulation of Kv1-channels. Together, these results highlight the strong neuroprotective capacity of PKG inhibitors for both photoreceptors and retinal ganglion cells, illustrating their broad potential for the treatment of retinal diseases and possibly neurodegenerative diseases in general.

Preventing Small-for-size Syndrome in Living Donor Liver Transplantation: Guidelines From the ILTS-iLDLT-LTSI Consensus Conference.

Small-for-size syndrome (SFSS) is a well-recognized complication following liver transplantation (LT), with up to 20% developing this following living donor LT (LDLT). Preventing SFSS involves consideration of factors before the surgical procedure, including donor and recipient selection, and factors during the surgical procedure, including adequate outflow reconstruction, graft portal inflow modulation, and management of portosystemic shunts. International Liver Transplantation Society, International Living Donor Liver Transplantation Group, and Liver Transplant Society of India Consensus Conference was convened in January 2023 to develop recommendations for the prediction and management of SFSS in LDLT. The format of the conference was based on the Grading of Recommendations, Assessment, Development, and Evaluation system. International experts in this field were allocated to 4 working groups (diagnosis, prevention, anesthesia, and critical care considerations, and management of established SFSS). The working groups prepared evidence-based recommendations to answer-specific questions considering the currently available literature. The working group members, independent panel, and conference attendees served as jury to edit and confirm the final recommendations presented at the end of the conference by each working group separately. This report presents the final statements and evidence-based recommendations provided by working group 2 that can be implemented to prevent SFSS in LDLT patients.

HDAC inhibition delays photoreceptor loss in Pde6b mutant mice of retinitis pigmentosa: insights from scRNA-seq and CUT&Tag.

Purpose: This research aimed to ascertain the neuroprotective effect of histone deacetylase (HDAC) inhibition on retinal photoreceptors in Pde6brd1 mice, a model of retinitis pigmentosa (RP). Methods: Single-cell RNA-sequencing (scRNA-seq) explored HDAC and poly (ADP-ribose) polymerase (PARP)-related gene expression in both Pde6b-mutant rd1 and wild-type (WT) mice. The CUT&Tag method was employed to examine the functions of HDAC in rd1 mice. Organotypic retinal explant cultures from WT and rd1 mice were exposed to the HDAC inhibitor SAHA (suberoylanilide hydroxamic acid) postnatally, from day 5 to day 11. The terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assay was applied to quantify the percentage of photoreceptor loss in the outer nuclear layer (ONL). HDAC activity was confirmed to be inhibited by SAHA through an HDAC activity assay. Moreover, the study evaluated PARP activity, a key driver of the initial response to DNA damage during photoreceptor degeneration, following HDAC inhibition. Results: The scRNA-seq revealed that diverse roles of HDAC and PARP isoforms in photoreceptor cell death. HDAC-related genes appeared to regulate cell death and primary immunodeficiency. Alterations in HDAC activity were consistent with the TUNEL-positive cells in the ONL at different time points. Notably, SAHA significantly postponed photoreceptor loss and decreased HDAC and PARP activity, thereby implicating both in the same degenerative pathway. Conclusions: This study highlights that the interaction between HDAC inhibition and PARP can delay photoreceptor cell death, proposing a promising therapeutic approach for RP.

Pyruvate-conjugation of PEGylated liposomes for targeted drug delivery to retinal photoreceptors.

Despite several promising candidates, there is a paucity of drug treatments available for patients suffering from retinal diseases. An important reason for this is the lack of suitable delivery systems that can achieve sufficiently high drug uptake in the retina and its photoreceptors. A promising and versatile method for drug delivery to specific cell types involves transporter-targeted liposomes, i.e., liposomes surface-coated with substrates for transporter proteins highly expressed on the target cell. We identified strong lactate transporter (monocarboxylate transporter, MCT) expression on photoreceptors as a potential target for drug delivery vehicles. To evaluate MCT suitability for drug targeting, we used PEG-coated liposomes and conjugated these with different monocarboxylates, including lactate, pyruvate, and cysteine. Monocarboxylate-conjugated and dye-loaded liposomes were tested on both human-derived cell-lines and murine retinal explant cultures. We found that liposomes conjugated with pyruvate consistently displayed higher cell uptake than unconjugated liposomes or liposomes conjugated with lactate or cysteine. Pharmacological inhibition of MCT1 and MCT2 reduced internalization, suggesting an MCT-dependent uptake mechanism. Notably, pyruvate-conjugated liposomes loaded with the drug candidate CN04 reduced photoreceptor cell death in the murine rd1 retinal degeneration model while free drug solutions could not achieve the same therapeutic effect. Our study thus highlights pyruvate-conjugated liposomes as a promising system for drug delivery to retinal photoreceptors, as well as other neuronal cell types displaying high expression of MCT-type proteins.