BACKGROUND & AIMS:Glycosylated proteins and lipids regulate multiple cellular processes and play key roles in organ damage and regeneration. Recently, glycosylated non-coding small RNAs (glycoRNA) have been identified, however, their expression in the liver and their involvement in hepatic pathology has not yet been reported. METHODS:We detected the presence of glycoRNAs by northern blot and an imaging approach called sialic acid aptamer and RNA in situ hybridization-mediated proximity ligation assay that enables direct visualization of glycoRNAs. Restoration of key mediators of glycoRNA biosynthesis was achieved in vivo, via adeno-associated viral vectors (AAV). RESULTS:Here, we show that glycoRNAs are synthesized in human liver tissue, primary hepatocytes and hepatic tumor cells. In tissues from patients with key features of metabolic dysfunction-associated steatotic liver diseases (MASLD), the most prevalent liver disease worldwide, expression of most glycoRNAs was reduced. Mechanistically, we found that reduced expression of SID1 transmembrane family member 1 (SIDT1) and DTW domain containing 2 (DTWD2), two key mediators of glycoRNA biosynthesis, contribute to loss of glycoRNAs in MASLD. Inhibition of SIDT1 and DTWD2 increased fatty acid load in primary human hepatocytes and enhanced inflammation signals upon co-culture with macrophages. Importantly, AAV-mediated in vivo restoration of SIDT1 and DTWD2 attenuated metabolic dysfunction-associated steatohepatitis in mice. Furthermore, sequencing of enriched glycoRNA samples identified eight glycoRNAs that were downregulated in steatotic human liver and hepatocytes. CONCLUSIONS:Collectively, our study demonstrates the presence of glycoRNAs in human hepatocytes and human liver tissues and their dysregulated expression in experimental steatosis models and in patients with MASLD. IMPACT AND IMPLICATIONS:Recent estimates suggest that up to 24% of the world's population is affected by metabolic dysfunction-associated steatotic liver diseases (MASLD). Our study reports for the first time that glycosylated RNAs (glycoRNA), a recently discovered class of RNA, are present in the liver and their expression is dysregulated in fatty liver injury. Importantly, in vivo restoration of glycoRNA biogenesis, attenuated fatty liver injury in preclinical models of MASLD. Furthermore, our results suggest that glycoRNA expression is dysregulated in human livers with MASLD, indicating their potential as novel biomarkers of liver injury.

Heterozygous familial hypercholesterolemia is a common genetic disorder characterized by lifelong elevation of serum low-density lipoprotein cholesterol (LDL-C) and premature atherosclerotic cardiovascular disease. YOLT-101 is an investigational in vivo gene therapy that uses adenine base-editing technology, delivered via GalNAc-modified lipid nanoparticles to inactivate PCSK9 and achieve sustained LDL-C reduction. Here we report interim results from an ongoing clinical trial evaluating primary (safety and tolerability) and secondary (lowering of PCSK9 and LDL-C levels) outcomes of a single intravenous dose of YOLT-101 in adults with heterozygous familial hypercholesterolemia and uncontrolled LDL-C. Six participants (three men and three women) received escalating doses of YOLT-101 (0.2, 0.4 or 0.6 mg kg-1). No grade ≥3 adverse events occurred. Transient and self-limited infusion-related reactions and elevations in liver enzymes were the most common adverse events. A single infusion of YOLT-101 induced dose-dependent and durable reductions in circulating PCSK9 and LDL-C, with sustained reductions of 74.4% and 52.3%, respectively, at 24 weeks in the 0.6 mg kg-1 cohort (n = 3), demonstrating promise for future clinical development. ClinicalTrials.gov registration: NCT06458010 .

Background: Alpha-1 antitrypsin deficiency (AATD) caused by the PI*ZZ mutation (Glu342Lys) results in hepatic accumulation of misfolded AAT-Z protein and reduced circulating AAT levels, leading to progressive liver disease and emphysema. Gene correction therapy represents a potentially curative approach by directly correcting the underlying genetic defect. We report the first case of successful hepatic gene correction with early histological and functional assessment. Methods/Case presentation: We report the case of a 66-year-old male patient with PI*ZZ AATD who underwent gene correction therapy within the YOLT-202 phase I/Ia clinical trial (clinical trial.gov ID NCT07193615). Ten weeks post treatment a liver biopsy was performed to re-evaluate pre-existing F2 liver fibrosis as measured by elastography before entering the study. Serum samples allowed functional assessment of the AAT-mediated elastase inhibition. Results: Liver biopsy did not show signs of hepatic inflammation and demonstrated 54% (Sanger) and 57% (Illumina) gene correction rate of the PI*ZZ variant on the DNA level with no bystander edits or off-target effects. Following a transient elevation of transaminases during the early post-treatment period, liver enzymes normalized. Monthly serum AAT measurements demonstrated biologically active and stable therapeutic levels throughout follow-up. Conclusions: This case demonstrates efficient and precise hepatic gene correction without concerning histological alterations and with substantial improvement of functional parameters, supporting the feasibility and safety of gene editing approaches for AATD.

​Background: Long-term treatment with lithium can cause kidney damage. It has been hypothesised that single daily lithium dosing (SDD) minimizes kidney damage and SDD, given in the evening, has been widely endorsed by the medical community. However, kidney physiology suggests that SDD in the evening might maximise rather than minimise kidney damage. This review aims to assess if SDD compared with multiple daily lithium dosing (MDD) results in less kidney impairment. Methods: This PROSPERO-registered (CRD42024537460) systematic review was conducted in accordance with the PRISMA guidelines. PubMed and Web of Science were searched to identify studies investigating the effect of different lithium dosing regimens on kidney function, published up to 31 December 2024. Owing to substantial heterogeneity across studies, outcomes were synthesised narratively in accordance with the SWiM (Synthesis Without Meta-analysis) reporting guideline. Study validity was assessed across four domains: (a) kidney outcome adequacy, (b) statistical power, (c) control of confounders, and (d) methodological rigour. Certainty of evidence was evaluated using the GRADE approach. Findings: Of 709 records screened, 19 studies and one case report were included, comprising 6787 patients. The largest study, analysing 5751 patients, did not report the number of patients on SDD or MDD. The remaining studies, including the case report, included 492 patients on SDD and 576 on MDD. Only one study was of fair validity, finding no difference in kidney outcomes between dosing regimens. The remaining 18 studies and the case report were of poor validity. The certainty of evidence for SDD in terms of kidney protection was very low. Interpretation: Current evidence does not support the hypothesis that a lithium dose given as SDD in the evening, compared to MDD, is superior for the prevention or containment of kidney impairment.

BACKGROUND & AIMS:HFE-related hereditary hemochromatosis is caused by loss-of-function mutations in the HFE gene, leading to excessive intestinal iron absorption and hepatic deposition. The C282Y variant in homozygosity accounts for 80-90% of diagnosed cases. If untreated, iron accumulation can cause liver fibrosis, cirrhosis, and hepatocellular carcinoma. METHODS:We employed lipid nanoparticles (LNPs) to deliver base editor mRNA and single-guide RNA for in vivo correction of the HFE C282Y mutation in a murine model under iron challenge. Additionally, patient-derived induced pluripotent stem cells (iPSCs) and hepatocyte-like cells were edited using the same approach. RESULTS:Base editing achieved a conversion rate of 73.6 ± 4.9% in cultured murine hepatocytes and up to 67% in vivo. No off-target effects were detected at genomic sites with one or two mismatches, as confirmed by next-generation sequencing. Treated mice showed significantly reduced hepatic iron overload despite continued high dietary iron intake. Transcriptomic analysis revealed decreased signatures associated with fibrosis and cancer. For preclinical evaluation, iPSCs from C282Y homozygous patients were differentiated into hepatocyte-like cells. LNP-mediated base editing achieved up to 63.8 ± 0.8% correction in these cells, again without detectable off-target activity. CONCLUSIONS:These results provide proof of concept that base editing of the C282Y variant is both safe and efficient in vivo and in human-derived cells, effectively reducing hepatic iron accumulation and preventing fibrotic remodeling. IMPACT AND IMPLICATIONS:HFE C282Y-related hemochromatosis lacks causal therapies and carries a risk of iron-driven liver disease, supporting the need for precise in vivo gene correction. Here, LNP-mediated adenine base editor delivery enabled efficient editing in hepatocytes and induced pluripotent stem cell-derived models, reducing hepatic iron and normalizing biomarkers without detectable safety concerns. These findings highlight translational potential for non-viral gene correction, though further validation in larger and long-term studies is required.

Background & Aims: The shortage of liver donors remains a critical challenge in the treatment of end-stage liver failure. Previous studies have explored ectopic transplantation of hepatocyte organoids or spheroids to support unstable liver function. We hypothesized that the addition of non-parenchymal liver cells to hepatocyte organoids would improve overall survival in acute liver failure. Here, we aimed to engineer DNA origami-mediated multi-lineage liver microtissue (NAC-liver microtissue) and evaluate its therapeutic efficacy in a mouse model of acute liver failure. Methods: We employed self-assembling nucleic acid nanostructures (NAC) to construct two types of liver microtissues: one composed exclusively of hepatocytes (NAC-hepatocyte microtissue) and another incorporating both hepatocytes and non-parenchymal cells (NAC-liver microtissue). We then investigated their hepatic functional properties in vitro and evaluated therapeutic efficacy in vivo through intraperitoneal transplantation into mice undergoing extended hepatectomy. To explore the underlying mechanisms, we performed histological analysis and RNA sequencing of the remnant liver. Results: NAC-liver microtissue exhibited superior scalability, uniformity, and stable, enhanced hepatic functional activity compared to NAC-hepatocyte microtissue in vitro (n = 4, p <0.001). In vivo, transplantation of NAC-liver microtissue markedly improved survival in mice undergoing extended hepatectomy compared with untreated controls (70% [n = 10] vs. 8.3% [n = 12], p <0.001), whereas NAC-hepatocyte microtissue demonstrated moderate efficacy (25%, n = 8). Furthermore, NAC-liver microtissue transplantation improved liver function, lipid oxidation, and sinusoidal vascular network formation in the remnant liver of mice following extended hepatectomy. Conclusions: These findings provide therapeutic evidence supporting NAC-liver microtissue transplantation as a potential treatment for acute liver failure and highlight a novel strategy for extrahepatic cellular support in severe liver injury. Impact and implications: Although hepatocyte organoid or spheroid transplantation has long been explored as a potential therapy for liver disease, these approaches fail to replicate the cellular complexity of the liver, resulting in suboptimal functionality and limited therapeutic benefit. The therapeutic potential of multi-lineage liver microtissue for liver failure has not previously been reported. Here, we demonstrate that NAC-liver microtissue, composed of hepatocytes and non-parenchymal cells, provides superior functional outcomes both in vitro and in vivo compared with NAC-hepatocyte microtissue. These findings highlight the indispensable role of non-parenchymal cells in maintaining hepatic functionality and support the therapeutic potential of multi-lineage liver microtissue for patients with severe liver disease.

BACKGROUND:Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths, globally. There is a need for novel biomarkers for early detection and novel, effective targeted therapies. Molecular imaging can faithfully visualize, characterize and quantify specific relevant biological processes. BASIC PROCEDURE:We performed longitudinal dedicated small-animal positron emission tomography-computed tomography (PET/CT) imaging to analyze changes in glucose metabolism using [18F]fluorodeoxyglucose ([18F]FDG), amino acid turnover with [18F]fluoroethyltyrosine ([18F]FET), and chemokine receptor expression using [68Ga]pentixafor targeting CXCR4, during stages of early tumor development, overt HCC and regression. We used two conditional transgenic mouse models of HCC, driven by clinically relevant oncogenes c-MYC (LT2/MYC) or HRASV12 (LT2/RAS). Conditional doxycycline-regulated mouse models, enable liver-specific oncogene activation or inhibition, leading to liver tumor development and regression, respectively. Correlation of our PET/CT findings with our gene expression and metabolomics data and with histological analyses followed. MAIN FINDINGS:We show PET/CT identifies HCC stage-specific and oncogene-specific molecular changes that may serve as potential novel biomarkers and therapeutic targets. Glucose metabolism and CXCR4 chemokine expression are differentially deregulated during HCC development in an oncogene-specific manner. Our [18F]FDG results correlated with glucose transporter GLUT1 gene expression and with our metabolomics data. Increased expression of CXCR4 and CD68 inflammatory markers mirrored [68Ga]pentixafor results in LT2/MYC mice. FET-based measurement of amino acid turnover are insensitive to stages of HCC-development, in our studies. Concurrently, no significant changes in expression of tyrosine metabolism genes were observed. PRINCIPAL CONCLUSIONS:Our study highlights that identified changes in targeted molecular imaging can facilitate a better understanding of underlying biological processes and may help guide novel oncogene-specific targeted anti-tumor therapies in HCC, with promising translational potential.

Apheresis is used for the treatment of many different diseases, especially when conventional therapy lacks efficacy. There are however some diseases in which apheresis is accepted as first line therapy. The aim of this analysis was to investigate the use of apheresis for the treatment of neurological diseases and the changes over two decades in the World Apheresis Association registry. During the period 2003-2023, a total of 23,699 apheresis procedures in 2963 patients with a neurological disease were performed. Data were collected during different periods by 44 centers, out of which 22 centers had been registering continuously over the latest 10 years. An increase in the proportion of neurological diseases developed over the period (p < 0.001) while the overall apheresis procedures remained stable (p = 0.46). Most procedures were due to myasthenia gravis (MG; n = 11,049 (31 % of patients), Guillain-Barré Syndrome (GBS; n = 3247 (30 %), multiple sclerosis (MS; n = 2665 (18 %)), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP; n = 2367 (3 %)), and neuromyelitis optica (NMO; n = 650 (2 %)). A change in the proportion of these diseases was noted over time. Adverse events (AEs) differed significantly between the diseases. Patients with GBS had most moderate and severe AEs. Hypotension was the most common severe AE. The panorama of different neurological diseases may cause different AEs based on the variation in neurological response to the apheresis procedure and replacement fluid. It is important to expand this knowledge among those who are prescribing and those performing the apheresis procedures.

The WAA registry has been active since 2002. It allows bed side registration of safety and efficacy data. The data each center enters is accessible for its own use but also used for merged analysis. Most types of procedures are represented. Treatments of many severe diseases as well as the collection of autologous and donor cells for therapeutic use especially in oncologic diseases are recorded. Previous reports have shown a successive reduction in adverse events (AE) over the years. The aim of the present report is to update data of the risk for AE during the years from 2013 to Oct 2024. Contributions of 44 centers from 20 countries were analysed. Over these years, more than 169,000 apheresis procedures have been registered in more than 26,000 patients. During the study period the mean incidence of AE, merged for all types of procedures, was 1.6 /100 procedures for mild, 2.0/100 for moderate and 0.20/100 for severe AE, and reduced since 2013. Since 2002, death due to apheresis could not be excluded in one patient. There was an increased risk of hypotension during apheresis in patients with neurological diagnoses (ICD-10 chapter G) versus those with diseases of the musculoskeletal or connective tissue (ICD-10 chapter M) and vice versa for urticaria and tingling. In conclusion, the present data show the risk for various degrees of AE in apheresis procedures. Many patients suffer from severe illness and apheresis is often offered as a rescue therapy. Although the risk of death due to the apheresis procedure is extremely rare the concomitant severe disease itself poses a risk for severe events.

Background: Despite the therapeutic benefits, non-adherence to lithium is common. One recent study showed that most patients discontinue lithium due to adverse effects. Little is known about individuals starting and discontinuing lithium repeatedly. Objectives: We aimed to determine reasons for discontinuing and restarting lithium multiple times in patients with bipolar or schizoaffective disorder. Design: Retrospective cohort study based on psychiatric case records of the SLaM Biomedical Research Centre Case Register (SLaM BRC case register). Method: Anonymised clinical data were extracted via the Clinical Record Interactive Search (CRIS) application. Patients with at least three events of lithium discontinuation between 2012 and 2022 were included. Results: Of 2888 eligible patients, 123 patients had discontinued lithium on at least three occasions. Psychiatric reasons, such as suspected lack of insight, feeling subjectively well or disagreeing with diagnosis, were the most common reasons for lithium discontinuations. They accounted for 77.2% of cases in the first event of discontinuation, 73.2% in the second and 72.3% in the third event. Adverse physical effects accounted for 19.5% of cases in the first event of discontinuation, 25.2% in the second and 26.0% in the third event. Relapse into the underlying affective disorder accounted for 83.7% each of reinstatements in the first and second events and 82.1% in the third event. Discussion: In our sample, lithium was discontinued due to adverse effects in only a minority of patients. In most cases, the reasons for lithium discontinuation were considered psychiatric. Lithium was mainly restarted due to relapse. This warrants a better understanding of the reasons for repeatedly discontinuing lithium and the best way to promote lithium adherence to prevent a perpetual cycle of remitting when on lithium and relapsing when off lithium.

Liver transplantation remains constrained by the scarcity of donor organs and the risks inherent in the procedure, underscoring the urgent need for novel cirrhosis therapies. We developed a protocol to convert human primary hepatocytes into expandable hepatocyte-derived liver progenitor-like cells (HepLPCs), which secrete high levels of matrix metalloproteinases and hepatocyte growth factor. In a thioacetamide-induced rat model of cirrhosis, human HepLPCs demonstrated potent anti-fibrotic properties and promoted liver regeneration. Biodistribution studies revealed that most xenogenic HepLPCs were cleared from the body within one week, suggesting that their therapeutic benefits likely arise from paracrine signaling rather than long-term engraftment. We initiated a first-in-human clinical trial involving nine patients with cirrhosis to evaluate the feasibility and safety of HepLPCs. Preclinical toxicity assessments in 36 crab-eating macaques confirmed the safety of HepLPC treatment. In the clinical trial, nine patients (mean age: 53 years), primarily with HBV-related cirrhosis, received HepLPCs via trans-hepatic arterial infusion without immunosuppressants. No serious adverse event was observed, and the minor adverse events were consistent with those commonly seen in cirrhosis patients. The treatment was well tolerated, with no transfusion reactions or dose-limiting toxicities. While significant changes in Child-Pugh and MELD scores were not observed, some patients showed improvements in liver biochemical parameters, coagulation profiles, and portal hypertension indicators during the six-month follow-up. These findings indicate that HepLPC therapy is safe and feasible, offering a promising new strategy for treating cirrhosis. Further clinical trials are needed to assess its efficacy in patients with decompensated cirrhosis and acute-on-chronic liver failure.

Stem cell-based therapy holds great potential for substituting degenerated motor neurons (MNs) in amyotrophic lateral sclerosis (ALS). Missing protocols for advanced differentiation of transplanted cells into MNs, immune rejection, and the lack of suitable ALS models for preclinical trials have slowed the development of effective therapies. Here, we employed multiplex genetic-editing to generate a novel human pluripotent stem cell line containing doxycycline (Dox)-inducible MNs-specific transcription factors and comprehensively modified immunomodulatory genes. We transplanted these cells into the spinal cord of ALS large animal models (SOD1G93A pigs and TIA1P362L rabbits), which faithfully recapitulate pathologies and symptoms observed in ALS patients. The transplanted cells could efficiently differentiate into functional MNs upon Dox treatment in vivo, distribute throughout the spinal cord and motor cortex via extensive migration, survive long-term without the need for immunosuppression. Notably, these MNs integrated into host neural circuits, as evidenced by their long projection of peripheral axons to target muscle and reformation of neuromuscular junctions. As result, pathologies and motor deficits were substantially ameliorated in both animal models. One Sentence Summary Hypoimmunogenic human motor neurons induced from iPSCs in vivo reform neuromuscular junctions and ameliorate ALS disease in pig and rabbit models. ### Competing Interest Statement The authors have declared no competing interest.

BACKGROUND:Long-term lithium treatment decreases kidney function. However, it remains unclear whether stopping lithium improves kidney function. OBJECTIVES:To study kidney function in patients who stopped and subsequently restarted lithium treatment. METHODS:Mirror-image design using data from the LiSIE retrospective cohort study. The mirror was set to when lithium was stopped with a 5-year pre- and post-mirror period. Adult patients with bipolar, schizoaffective disorder or unipolar depression, who had lithium ≥4.5 years in the pre-mirror period, were included. Creatinine measurements were available from 1997 to 2017. The main outcome was the difference in mean annual change of the estimated glomerular filtration rate (eGFR) adjusted for sex, hypertension and diabetes mellitus. RESULTS:A total of 168 participants (94 women, 74 men) were included. Mean annual eGFR change was -1.58 (-1.87 to -1.28) mL/min/1.73 m2/year before and -0.023 (-0.49 to +0.44) mL/min/1.73 m2/year after lithium discontinuation (p < 0.0001 for difference). The improvement was 0.77 (0.35-1.20) mL/min/173 m2/year in participants with eGFR >60 mL/min/1.73 m2, and 3.03 (2.15-3.92) mL/min/1.73 m2/year for participants with eGFR <30 mL/min/1.73 m2. The effect was persistent over the 5-year post-mirror study period. For participants restarting lithium, the mean annual eGFR change was -1.71 (-2.26 to -1.16) mL/min/1.73 m2/year, a setback compared to their lithium-free post-mirror period (p < 0.0001). We did not see any difference compared to the pre-mirror period (p = 0.51). CONCLUSIONS:Stopping lithium slowed down mean eGFR decline. This effect was more pronounced in participants with lower eGFR at the time of lithium discontinuation. In participants who restarted lithium, the annual decline of eGFR reverted to pre-lithium discontinuation levels.

BACKGROUND:By entering collecting duct principal cells via the epithelial sodium channel (ENaC), lithium is capable of inducing vasopressin insensitivity, resulting in excessive urine production, nephrogenic diabetes insipidus (NDI) and potential for other long-term forms of renal dysfunction. ENaC inhibitors (ENaC-I) such as amiloride have been shown in animal models to minimise this adverse effect, and while ENaC-I are often considered an effective strategy, the literature on ENaC-I for lithium-related polyuria has not yet been synthesised despite the importance of this topic. This review aimed to identify all published evidence for adjunctive use of an ENaC-I for lithium-related polyuria to estimate its effectiveness while also exploring potential moderators of effectiveness. METHOD:The systematic search covered databases MEDLINE, EMBASE and PsycINFO complemented by handsearches, aiming to identify all studies of ENaC-I interventions in lithium-treated patients with pre- and post-ENaC-I polyuria as outcomes. RESULTS:10 studies totalling 25 participants were eligible for inclusion and were synthesised narratively. Amiloride was the ENaC-I used in 24/25 participants, and triamterene in the other. 8/10 publications were single case reports, 4 of which presented substantial confounding issues. Clear improvements to polyuria were demonstrated in most papers, including the two larger studies. CONCLUSIONS:Although it appears very likely that ENaC inhibitors help ameliorate polyuria in lithium-treated patients, the quantity and quality of evidence is low. Heterogeneity in patient characteristics, intervention characteristics and study designs limit conclusions regarding the contribution of factors likely to influence ENaC-I effectiveness for lithium-induced polyuria. Besides, adverse effects require further exploration.

Hereditary spastic paraplegia type 5 (SPG5) is an autosomal recessive neurological disorder caused by mutations in the CYP7B1 gene, which encodes cholesterol 7α-hydroxylase, an essential enzyme in cholesterol metabolism. These mutations lead to elevated levels of 25- and 27-hydroxycholesterol, oxysterols known to be neurotoxic and blood-brain-barrier permeable. Their accumulation contributes significantly to SPG5 pathogenesis, resulting in spastic gait disturbance and severely impaired quality of life. Using a Cyp7b1-/- mouse model that mirrors the metabolic phenotype of SPG5, we developed a gene therapy approach to correct oxysterol imbalance. We designed an AAV8-TTR-hCYP7B1 vector to deliver the CYP7B1 gene specifically to the liver. Following intravenous administration, oxysterol levels in blood and liver were rapidly normalized, even at low doses (1E10), with no observed toxicity at the highest tested dose (1E11). Despite these promising peripheral results, oxysterol levels in the brain, particularly 27-hydroxycholesterol, remained only partially corrected six weeks post-treatment. Our findings suggest that while liver-targeted gene therapy is effective at restoring peripheral cholesterol metabolism, a successful therapeutic strategy for SPG5 must also address central nervous system involvement. We conclude that successful treatment of SPG5 would require a novel gene therapeutic approach that also targets the CNS.

PURPOSE:The liver-brain axis regulates metabolic homeostasis, with glucose metabolism playing a key role. Liver dysfunction, such as fibrosis, may impact brain metabolism and consequently, brain function. Positron emission tomography (PET) imaging provides a non-invasive approach to study glucose metabolism in both organs. A recent longitudinal PET/CT study utilizing 2-deoxy-2-[18F]-fluoro-d-glucose ([18F]FDG) amongst other radiotracers revealed significant metabolic changes in the liver in a mouse model of liver fibrosis. Here, we retrospectively analyzed those data to quantify potential associated changes in brain glucose metabolism. PROCEDURES:Eleven male C57BL/6N mice underwent repeated PET imaging with [18F]FDG at baseline, pre-fibrosis, fibrosis, and remission stages. Cerebral glucose metabolism was assessed using standardized uptake value (SUV), blood glucose-corrected SUV (SUVgluc), and kinetic modeling (Patlak and two-tissue compartment models) for calculation of the glucose metabolic rate (MRGlu). RESULTS:Both SUVgluc and MRGlu significantly decreased during pre-fibrosis and fibrosis on whole brain level and recovered at remission. SUVgluc statistical parametric mapping identified multiple brain areas with reduced glucose metabolism, which was confirmed by regional analysis showing progressive reduction in SUVgluc. Correlation analyses confirmed SUVgluc as a reliable surrogate for MRGlu, unlike uncorrected SUV. Liver [18F]FDG uptake increased during fibrosis and normalized at remission, mirroring changes in blood glucose concentrations. CONCLUSIONS:[18F]FDG PET imaging revealed that liver fibrosis alters glucose metabolism in both liver and brain, emphasizing the potential of molecular imaging for future assessment of metabolic interaction between liver and brain. [18F]FDG uptake in terms of SUVgluc strongly correlated with MRGlu from kinetic modeling, supporting its utility as a valid surrogate parameter to quantify cerebral glucose metabolism in mice.

Primary hyperoxaluria type 1 (PH1) is a rare inherited liver disorder caused by alanine glyoxylate aminotransferase (AGT) dysfunction, leading to accumulation of glyoxylate which is then converted into oxalate. Excessive oxalate results in kidney damage due to deposition of oxalate crystals. We have developed an mRNA-based protein replacement therapy for PH1 to restore normal glyoxylate to glycine metabolism. Sequence optimized human AGT mRNA (hAGT mRNA) was encapsulated in lipopolyplex (LPP) and produced functional AGT enzyme in peroxisomes. Pharmacokinetics and pharmacodynamics (PK/PD) were evaluated in vitro and in vivo. PK demonstrated that AGT mRNA and AGT protein maintained high expression levels for up to 48 hours. A single 2 mg/kg dose in AgxtQ84-/- rats achieved a 70% reduction in urinary oxalate. Toxicological assessment identified the highest nonserious toxic dose (HNSTD) as 2 mg/kg. These findings affirm the efficacy and safety of hAGT mRNA/LPP and support its clinical application in PH1 treatment.

Background & Aims: Liver fibrosis and its end-stage form cirrhosis contribute to millions of deaths annually. The lack of robust antifibrotic molecules is in part attributed to the absence of any functional screens to identify molecular regulators using patient- derived primary human hepatic myofibroblasts, which are key drivers of fibrosis. Methods: Here, to identify robust regulators of fibrosis, we performed functional microRNA screenings in primary human hepatic myofibroblasts followed by in vivo validation in three independent mouse models of fibrosis (toxin, cholestasis and MASH). Results: We identified miR-190b-5p and miR-296-3p as robust antifibrotic miRNAs that suppress liver fibrosis. Notably, the expression of miR-190b-5p and miR-296-3p was found to be significantly reduced in human livers with fibrosis. Mechanistically, we discovered hyaluronan synthase 2 ( HAS2 ) and integrin alpha-6 ( ITGA6 ) as novel targets of miR-190b-5p and miR-296-3p, respectively. Furthermore, we demonstrated that the antifibrotic properties of miR-190b-5p and miR-296-3p are, at least in part, dependent on HAS2 and ITGA6. Finally, we showed the antifibrotic function of both miRNAs in a human liver bud model, which mimics multiple features of the human liver. Conclusions: Collectively, in our study we discovered miR-190b-5p and miR-296-3p as two novel antifibrotic miRNAs, and that HAS2 and ITGA6 contribute to miR-190b-5p- and miR-296-3p-mediated inhibition of liver fibrosis. These results provide a foundation for future research to explore the clinical utility of miR-190b-5p and miR-296-3p in fibrosis. (c) 2024 The Authors. Published by Elsevier B.V. on behalf of European Association for the Study of the Liver. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).