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Permyakova, A.

Publications and source records attributed to Permyakova, A..

5 recordsLinked to original sources

Peripheral CB1R Blockade Suppresses AKI-to-CKD Maladaptive Repair

BackgroundAcute 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. MethodsWe 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. ResultsCB1R 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-{kappa}B-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 TNF/2-AG-induced expression of pro-inflammatory adhesion molecules, chemokines, cytokines, and arginine metabolism enzymes. ConclusionsCB1R 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 StatementPeripheral 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.

pharmacology and toxicology↗

Yttrium-90-doped metal-organic frameworks (MOFs) for low-dose rate intratumoral radiotherapy

Brachytherapy, or intratumoral radiation therapy, is a highly effective treatment option for localized tumors. Herein, we engineered injectable and biodegradable metal-organic frameworks (MOFs) to deliver the therapeutic radioisotope yttrium-90 (90Y). Particles of bimetallic MIL-100(Fe,Y) and Y-BTC, doped with 90Y and 88Y, were synthesized in a single step and retained radioyttrium in various buffer solutions. Tumor injectability and radioisotope retention were evaluated using tumor-bearing mice. In vivo analysis and calculations showed that radiolabeled MIL-100(Fe,Y) emitted more than 38% of its radioactivity, while Y-BTC emitted greater than 75% of its radioactivity, through 7 days at the tumor site upon intratumoral injection, without significant yttrium accumulation in off-target tissues. The anticancer effects of MIL-100(Fe,Y,90Y) and 90Y,Y-BTC particles were assessed using 3D multicellular tumor spheroids and a tumor-bearing mouse model, respectively. 90Y-doped MIL-100(Fe,Y) particles penetrated A549 tumor spheroids and caused superior cytotoxic effects compared to non-radioactive particles or 90YCl3, added at the same dose. Brachytherapy with 90Y-doped Y-BTC MOFs induced inhibition of B16F1 melanoma tumor growth and resulted in an increased median survival of 8.5 days compared to 4.5 days in untreated mice. This study exhibits the feasibility to prepare radioactive 90Y-containing biodegradable, non-toxic MOF particles that are advantageous for low-dose rate internal radiotherapy.

biophysics↗

Limiting mitochondrial-derived ATP transfer to the cytosol enhances T-cell activation

T-cell activation requires a substantial increase in NAD+ production, often exceeding the capacity of oxidative phosphorylation (OXPHOS). To investigate how T cells adapt to this metabolic challenge, we generated T cell-specific ADP/ATP translocase-2 knockout (Ant2-/-) mice. Loss of Ant2, a crucial protein mediating ADP/ATP exchange between mitochondria and cytoplasm, induces OXPHOS restriction by limiting ATP synthase activity, impeding NAD+ regeneration. Interestingly, Ant2-/- naive T cells exhibited enhanced activation, proliferation, and effector functions compared to wild-type controls. Metabolic profiling revealed that these cells adopt an activated-like metabolic program with increased mitobiogenesis and anabolism. Pharmacological inhibition of ANT in wild-type T cells recapitulated the Ant2-/- phenotype, and improved adoptive cell therapy of cancer. Our findings suggest that Ant2-deficient T cells bypass the typical metabolic reprogramming required for activation, leading to enhanced T-cell function. These results highlight the critical role of mitochondrial metabolism in regulating T-cell fate and underscore the therapeutic potential of targeting ANT for immune modulation.

immunology↗

Inhibition of somatostatin enhances the long-term metabolic outcomes of sleeve gastrectomy in mice

Bariatric surgery is an effective obesity treatment, leading to weight loss and improvement in glycemia, that is characterized by hypersecretion of gastrointestinal hormones. However, weight regain and relapse of hyperglycemia are not uncommon. Here, we investigated the role of somatostatin (Sst) in bariatric surgery outcomes using a mouse model of sleeve gastrectomy (SG). Sst knockout (sst-ko) mice fed with a calorie-rich diet gained weight normally, and had a mild favorable metabolic phenotype compared to heterozygous sibling controls, including elevated plasma levels of Glp1. Mathematical modeling of the feedback inhibition between Sst and Glp1 showed that Sst exerts its maximal effect on Glp1 under conditions of high hormonal stimulation, such as following SG. Obese sst-ko mice that underwent SG had higher levels of Glp1 compared with heterozygous SG-operated controls. Accordingly, SG-sst-ko mice regained less weight than controls and maintained lower glycemia months after surgery. Obese wild-type mice that underwent SG and were treated daily with a Sst receptor inhibitor for two months, had higher Glp1 levels, regained less weight, and improved glycemia compared to saline- treated SG-operated controls. Our results suggest that Sst signaling inhibition enhances and maintains the long-term favorable metabolic outcomes of bariatric surgery.

physiology↗

A new drug candidate for glycogen storage disorders enhances glycogen catabolism: Lessons from Adult Polyglucosan Body Disease models

This work employs Adult Polyglucosan Body Disease (APBD) models to explore the efficacy and mechanism of action of 144DG11, a new polyglucosan-reducing lead compound discovered by a high-throughput screen (HTS). APBD is an adult onset glycogen storage disorder (GSD) manifesting as a debilitating progressive axonopathic leukodystrophy. APBD is caused by glycogen branching enzyme (GBE) deficiency leading to poorly branched and insoluble glycogen inclusions, which precipitate as neuropathogenic polyglucosans (PG). 144DG11 led to prolonged survival and improved motor parameters in a GBE knockin (Gbeys/ys) APBD mouse model. Histopathologically, 144DG11 reduced PG and glycogen levels in brain, liver, heart, and peripheral nerve. Indirect calorimetry experiments revealed that 144DG11 increases carbohydrate burn at the expense of fat burn, suggesting metabolic mobilization of pathogenic PG. These results were also reflected at the cellular level by increased glycolytic, mitochondrial and total ATP production. Mechanistically, we show that the molecular target of 144DG11 is the lysosomal membrane protein LAMP1, whose interaction with the compound, similar to LAMP1 knockdown, enhanced autolysosomal degradation of glycogen and lysosomal acidification. Enhanced mitochondrial activity and lysosomal modifications were also the most pronounced effects of 144DG11 in APBD patient fibroblasts as discovered by image-based multiparametric phenotyping analysis and corroborated by proteomics. In summary, this work presents a broad mechanistic and target-based characterization of 144DG11 in in vivo and cell models of the prototypical GSD APBD. This investigation warrants development of 144DG11 into a safe and efficacious GSD therapy. One Sentence SummaryA new compound, demonstrated to ameliorate APBD in vivo and ex vivo by autophagic catabolism of glycogen, may potentially become a universal drug for glycogen storage disorders.

neuroscience↗