Liad Hinden

Background: Acute kidney injury (AKI) frequently progresses to chronic kidney disease (CKD), yet mechanisms governing this transition remain poorly understood. The endocannabinoid system (ECS), particularly cannabinoid-1 receptor (CB1R), regulates inflammation and metabolism in various organs, but its role in post-AKI maladaptive repair is less established. Methods: We analyzed CB1R expression in kidney biopsies from pre- and post-transplant recipients and in murine AKI models (ischemia-reperfusion injury [IRI] and folic acid [FA]-induced AKI). Peripheral CB1R blockade was evaluated in FA-AKI model and in human primary kidney proximal tubule cells (hKPTCs). Spatial metabolomics, semi-targeted metabolomic profiling, and gene and protein expression characterized molecular mechanisms. Results: CB1R expression was increased in kidneys undergoing maladaptive repair in both humans and mice, but remained unchanged during acute injury. In the FA-induced AKI model, the ECS showed stage-specific alterations, with temporal and spatial fluctuations in endocannabinoid levels and their enzymatic regulators. Peripheral CB1R blockade during the repair phase preserved kidney function, reduced injury, and maintained systemic glucose homeostasis. Metabolomic and molecular analyses revealed that CB1R blockade restored dysregulated arginine metabolism and reduced AKT/NF-κB-p65 pathway in post-AKI kidneys, linking CB1R activation to inflammatory signaling. In hKPTCs, 2-AG-induced activation of CB1R increased VCAM1 expression, a failed-repair marker, while its antagonism reduced TNFα/2-AG-induced expression of pro-inflammatory adhesion molecules, chemokines, cytokines, and arginine metabolism enzymes. Conclusions: CB1R overactivation drives AKI-to-CKD progression by promoting inflammatory signaling and metabolic dysregulation. Peripheral CB1R blockade during the repair phase represents a novel therapeutic strategy to prevent maladaptive repair and CKD development after AKI. These findings establish CB1R as a phase-specific therapeutic target for post-AKI intervention. Translational Statement: Peripheral CB1R antagonists offer a first-in-class therapeutic strategy to halt progression from acute kidney injury (AKI) to chronic kidney disease (CKD) by selectively targeting maladaptive tubular repair. By blocking CB1R signaling specifically in the kidney, these agents attenuate inflammation, metabolic dysregulation, and fibrogenic pathways that drive failed repair, while sparing central nervous system CB1R and thereby minimizing neuropsychiatric adverse effects. This phase-specific, peripherally restricted approach supports the development of peripheral CB1R antagonists as a viable translational therapy to improve long-term renal outcomes after AKI.

Hyperglycemia is a principal driver of β cell failure and multiple-organ complications in diabetes. Chronic exposure to hyperglycemia overstimulates mTORC1, disrupting glucose metabolism and promoting ER stress, oxidative stress, and inflammation; however, the upstream metabolic signal(s) linking glucose to mTORC1 activation remains unclear. Here, we identified glucosamine as a key metabolite connecting elevated glucose to mTORC1 signaling in pancreatic islets and kidney, both major targets of hyperglycemic damage. Using ¹³ C ₆ -glucose metabolic labeling in diabetic rodents treated with or without the SGLT2 inhibitor dapagliflozin or insulin, combined with targeted metabolomics and metabolic flux analysis, we found that tissue glucose concentrations strongly correlated with glucosamine. A similar correlation with plasma glucose was conserved in humans with or without type 2 diabetes, and inversely associated with β cell function. In vitro, low-dose glucosamine stimulated mTORC1 in islets and kidney proximal tubule cells in an O-GlcNAcylation–dependent manner. Broad phosphoproteomics and transcriptomics analyses in β cells showed that glucosamine activated mTORC1-regulating pathways, induced oxidative stress, ER stress, and dedifferentiation. Genetic inhibition of β cell mTORC1 via heterozygous Raptor knockout, as well as pharmacologic inhibition of the glucosamine/mTORC1 axis through SGLT2 inhibition, alleviated β cell stress, improved glycemic control, and restored β cell function. These findings identified the glucosamine/mTORC1 pathway as an important mediator of β cell and kidney dysfunction in diabetes.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst formation, inflammation, and metabolic dysregulation. The endocannabinoid system (ECS), particularly the cannabinoid-1 receptor (CB ₁ R), regulates renal metabolism and inflammatory signaling, yet its role in ADPKD remains largely unexplored. Methods: We analyzed publicly available human kidney transcriptomic datasets (bulk microarray GSE7869; single-nucleus RNA-sequencing from ADPKD GSE185948, and diabetic kidney disease cohorts GSE195460) and validated findings in ADPKD patient kidney tissue versus non-cystic controls using quantitative PCR, liquid chromatography-tandem mass spectrometry, and Western blotting. Longitudinal disease progression was evaluated in Pkd1 ^RC/RC mice at 3, 6, 9, and 12 months, with comprehensive assessment of ECS components, endocannabinoid (eCB) levels, and kidney function parameters. Correlation examined associations between ECS markers and disease severity. Results: Human ADPKD kidneys demonstrated consistent upregulation of CNR1 transcripts across platforms, with single-nucleus analysis revealing enrichment in proximal tubule-derived populations including failed-repair proximal tubule cells. ADPKD tissue exhibited significant reductions in key ECS-metabolizing enzymes ( FAAH , NAPEPLD , MGLL ) and marked depletion of eCB ligands anandamide (AEA) and 2-arachidonoylglycerol (2-AG). In contrast, diabetic kidney disease showed minimal ECS alterations, indicating ADPKD-specific dysregulation. Pkd1 ^RC/RC mice recapitulated human findings, with Cnr1 upregulation beginning at 6 months and significant AEA/ N -oleoylethanolamine (OEA) depletion at 9–12 months. CB ₁ R protein elevation preceded ligand depletion, suggesting progressive receptor sensitization. Correlation analyses revealed robust associations between CB ₁ R/enzyme expression, eCB depletion, and declining kidney function (kidney weight-to-body weight ratio, blood urea nitrogen, and creatinine clearance). Conclusions: ADPKD kidneys exhibit disease-specific dysregulation of the ECS, characterized by increased CB ₁ R expression accompanied by paradoxical depletion of eCB ligands. These alterations correlate with cyst burden and functional decline across human and murine disease stages, identifying the ECS as a prominently affected pathway during ADPKD progression. While our findings establish a strong association between ECS dysregulation and disease severity, whether altered CB ₁ R signaling represents a causal driver of cystogenesis or a secondary, yet therapeutically targetable component of the cystic and injury response will require direct genetic or pharmacologic modulation of CB ₁ R/ECS signaling.

Background and Purpose: Cannabidiol (CBD) and cannabigerol (CBG) are non‐psychoactive phytocannabinoids with emerging therapeutic potential in metabolic dysfunction‐associated steatotic liver disease (MASLD). However, the molecular mechanisms underlying their beneficial effects remain incompletely understood. In this study, we assessed the metabolomic and lipidomic impact of CBD and CBG in a mouse model of diet‐induced obesity and MASLD. Experimental Approach: Male C57Bl/6 mice fed on a high‐fat diet for 14 weeks were treated for 4 weeks with daily intraperitoneal CBD, CBG or vehicle. Assessments included body composition, indirect calorimetry, glucose tolerance, serum biochemistry and VLDL‐triglyceride profiling. Hepatic mechanisms were examined by metabolomics, lipidomics, creatine kinase activity, cathepsin activity‐based probes and gene/protein expression, with a choline‐deficient diet cohort to test phospholipid‐dependence of CBG. Key Results: CBD or CBG treatment improved glycaemic control, reduced hepatic triglycerides and normalised serum lipids, without affecting energy expenditure. Metabolomics revealed increased hepatic phosphocreatine and creatine with enhanced creatine kinase activity, indicating phosphocreatine‐based energy buffering independent of fatty acid oxidation changes. Lipidomics showed reduced triglycerides and ceramides, with increased phospholipids and lysobisphosphatidic acids, correlating with restored hepatic cathepsin activity and improved lysosomal lipid degradation. CBG was ineffective in choline‐deficient MASLD, indicating phospholipid pathway dependence. Conclusions and Implications: These findings identify a novel, endocannabinoid system‐independent mechanism by which CBD and CBG enhance hepatic energy buffering and lysosomal function, contributing to improved liver lipid handling and supporting phytocannabinoids as promising MASLD therapeutics.

Background: The endocannabinoid system (ECS) regulates homeostasis, inflammation, and organ-specific function. In the kidney, ECS activity modulates renal hemodynamics, and its overactivation is linked to chronic injury. However, the importance of the ECS involvement in acute kidney injury (AKI) remains unclear. This study aimed to characterize changes in circulating endocannabinoid (eCB) levels before and after relief of upper urinary tract obstruction (UUTO), to better understand ECS dynamics during acute renal dysfunction. These findings may inform the development of novel biomarkers and therapeutic targets for renal injury. Objectives: To characterize changes in circulating eCB levels before and after relief of UUTO, and to compare responses between patients with and without AKI. Design: Prospective observational cohort with paired, within-person sampling. Methods: Patients presenting to the emergency department with acute renal colic due to obstructive urolithiasis who underwent kidney decompression within 24 h were prospectively enrolled. Clinical, laboratory, and imaging data plus paired blood samples for eCB analysis were collected pre and post-drainage. Patients were divided into two groups: those who had AKI at presentation, and non-AKI controls. Serum eCBs were quantified, and fold changes compared using nonparametric analysis. Results: Twenty-two patients enrolled (10 had AKI and 12 served as non-AKI controls). Serum N -acylethanolamines (NAEs) showed divergent responses between the two groups. In AKI, N -arachidonoylethanolamine (AEA), N -palmitoylethanolamine, and N -oleoylethanolamine increased following drainage ( p = 0.06, 0.008, 0.08). In contrast, patients without AKI demonstrated a reduction in NAE levels, with a significant AEA drop ( p = 0.03) after obstruction relief. Notably, the fold-change in NAE levels post-drainage was significantly higher in patients with AKI compared to those without AKI. Conclusion: Circulating NAEs increase following relief of obstruction in patients with acute renal dysfunction, suggesting a potential role for ECS activation in the pathophysiology of UUTO-induced kidney injury. These findings highlight the ECS as a promising target for further investigation as a possible therapeutic avenue in AKI. Trial registration: Not applicable.

This study reveals for the first time that TSC-associated kidney disease involves significant dysregulation of the endocannabinoid system in both murine models and human kidneys, characterized by altered endocannabinoid levels, enzyme expression changes, CB1R upregulation, and CB2R downregulation in cyst-lining epithelial cells. Treatment with the peripheral CB1R antagonist effectively suppressed mTORC1 hyperactivation and c-Myc expression, identifying CB1R as a novel therapeutic target for TSC-associated renal pathology.

Botulinum neurotoxins (BoNTs) block cholinergic signaling at neuromuscular junctions, inducing transient muscle paralysis while avoiding neuronal death. However, the mechanism(s) underlying these dual features are yet unknown. Here, we report accumulation of 5'Lys transfer RNA fragments (tRFs) in both BoNT/A-intoxicated cultured human neuroblastoma cells and submandibular glands from BoNT/A-intoxicated rodents. Importantly, we show that 5′LysTTT tRFs balance ferroptosis by cointeracting with the RNA-binding ferroptosis-inducing protein HNRNPM and the 3' untranslated region of the ferroptosis-inhibiting CHAC1 mRNA. Moreover, approximately 20% of the BoNT/A-induced tRFs shared an 11-nucleotide-long LysTTT and LysCTT tRFs-included motif, CCGGATAGCTC, which may target transcripts containing complementary sequences, including the UNC5B transcript that can regulate cell survival. Collectively, the multiple regulatory roles of tRF-5′LysTTT and the shared repetitive motif reveal mechanism(s) supporting the survival of cholinergic neurons under BoNT/A exposure. This understanding may predict the development of novel BoNT/A therapeutic avenues for treating diverse neuromuscular disorders and BoNT/A cosmetic procedures.

Aims/hypothesis: Insulitis, a hallmark of inflammation preceding autoimmune type 1 diabetes, leads to the eventual loss of functional beta cells. However, functional beta cells can persist even in the face of continuous insulitis. Despite advances in immunosuppressive treatments, maintaining functional beta cells to prevent insulitis progression and hyperglycaemia remains a challenge. The cannabinoid type 1 receptor (CB1R), present in immune cells and beta cells, regulates inflammation and beta cell function. Here, we pioneer an ex vivo model mirroring human insulitis to investigate the role of CB1R in this process. Methods: CD4⁺ T lymphocytes were isolated from peripheral blood mononuclear cells (PBMCs) from male and female individuals at the onset of type 1 diabetes and from non-diabetic individuals, RNA was extracted and mRNA expression was analysed by real-time PCR. Single beta cell expression from donors with type 1 diabetes was obtained from data mining. Patient-derived human islets from male and female cadaveric donors were 3D-cultured in solubilised extracellular matrix gel in co-culture with the same donor PBMCs, and incubated with cytokines (IL-1β, TNF-α, IFN-γ) for 24–48 h in the presence of vehicle or increasing concentrations of the CB1R blocker JD-5037. Expression of CNR1 (encoding for CB1R) was ablated using CRISPR/Cas9 technology. Viability, intracellular stress and signalling were assayed by live-cell probing and real-time PCR. The islet function measured as glucose-stimulated insulin secretion was determined in a perifusion system. Infiltration of immune cells into the islets was monitored by microscopy. Non-obese diabetic mice aged 7 weeks were treated for 1 week with JD-5037, then euthanised. Profiling of immune cells infiltrated in the islets was performed by flow cytometry. Results: CNR1 expression was upregulated in circulating CD4⁺ T cells from individuals at type 1 diabetes onset (6.9-fold higher vs healthy individuals) and in sorted islet beta cells from donors with type 1 diabetes (3.6-fold higher vs healthy counterparts). The peripherally restricted CB1R inverse agonist JD-5037 arrested the initiation of insulitis in humans and mice. Mechanistically, CB1R blockade prevented islet NO production and ameliorated the ATF6 arm of the unfolded protein response. Consequently, cyto/chemokine expression decreased in human islets, leading to sustained islet cell viability and function. Conclusions/interpretation: These results suggest that CB1R could be an interesting target for type 1 diabetes while highlighting the regulatory mechanisms of insulitis. Moreover, these findings may apply to type 2 diabetes where islet inflammation is also a pathophysiological factor. Data availability: Transcriptomic analysis of sorted human beta cells are from Gene Expression Omnibus database, accession no. GSE121863, available at https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSM3448161. Graphical