Biology subjects

Szanda, G.

Publications and source records attributed to Szanda, G..

3 recordsLinked to original sources

bioRxiv2026

State-dependent cannabidiol interactions with fentanyl-bound mouse μ-opioid receptor conformations: a three-state molecular dynamics study

We published recently that one of the main constituents of cannabis products, cannabidiol (CBD), is an efficacious negative allosteric modulator (NAM) of the mu opioid receptor (MOR1) (Bosquez-Berger et al., 2023). Here, we investigated how the presence of cannabidiol (CBD) is associated with fentanyl (FEN) binding across MOR1 conformations. We performed molecular dynamics simulations of systems containing FEN alone or FEN+CBD in three mouse MOR1 conformational backgrounds: active-like 5C1M, inactive-like 4DKL, and a modeled Morph50 intermediate between the 5C1M and 4DKL conformations. Three independently seeded 200 ns trajectories were analyzed per model and condition (18 trajectories total), with the trajectory treated as the independent unit. Across the matched 0-200 ns window, consensus CBD contacts and CBD-associated changes in FEN contacts were strongly state dependent. Corrected intracellular TM3 to TM6 analyses separated the expected active-like, intermediate, and inactive-like backgrounds but did not identify a CBD-associated shift that was consistent across both geometric definitions and all three replicates. Equal-weight replicate-composite density maps preserved both the shared ligand distributions and this between-trajectory variability. These descriptive results support receptor-state-dependent CBD, FEN, MOR1 interactions while emphasizing the limited inferential power of three trajectories per condition.

pharmacology and toxicology↗

bioRxiv2026

Integrated lipidomic and transcriptomic analyses reveal novel endogenous lipid signaling system regulation in skin and plasma during psoriasiform inflammation

Psoriasis is a chronic inflammatory skin disease characterized by keratinocyte hyperproliferation and immune dysregulation. Emerging clinical and experimental evidence suggests that endogenous lipid (endolipid) signaling systems, including the endocannabinoid system (ECS), represent a promising therapeutic target to treat psoriasis; however, comprehensive characterization of small-molecule endolipids and related proteins in psoriatic skin and their relationship to systemic changes remains limited. Here, we used the imiquimod (IMQ)-induced mouse model of psoriasis to perform combined lipidomic and transcriptional profiling of endolipid signaling in both skin and plasma. Targeted lipidomics revealed a striking divergence between tissues: most endolipids increased in inflamed skin but decreased in plasma, including the canonical ECS lipids anandamide and 2-arachidonoylglycerol. In contrast, selected lipid species, including taurine-conjugated metabolites (both N-acyl taurines and bile acids), were elevated in both tissues, indicating pathway-specific regulation. Targeted transcriptional analysis of whole skin showed reduced expression of key endolipid biosynthetic enzymes (Napepld, Dagla, Daglb) and the cannabinoid receptor Cnr1, while Cnr2 and ECS-related metabolic enzymes remained unchanged. Additional alterations were observed in transcripts involved in related endolipid signaling (Trpv1, Trpv4, Ppara, Pparg, Gpr55), bile acid metabolism (Fxr, Bsep, Fabp4, Fabp5, Cyp27a1, Cyp8b1), and inflammatory pathways (Cox-2). To resolve this apparent discrepancy between lipid levels and gene expression, we performed compartment-specific analyses of epidermal and dermal layers. These revealed a predominantly suppressive epidermal response across multiple ECS-related proteins, contrasted by a more variable dermal profile with selective preservation or upregulation, particularly of Cnr2. Together, these findings demonstrate that psoriasiform inflammation is associated with compartment-specific remodeling of endolipid signaling across skin and systemic compartments, underscoring the functional heterogeneity of epidermal and dermal layers. This dataset provides novel insights into the dysregulation of endolipid signaling systems in psoriasis and provides a foundation for the development of spatially informed, lipid-based therapeutic strategies.

molecular biology↗

bioRxiv2020

CB1R Regulates Soluble Leptin Receptor Levels via CHOP, Contributing to Hepatic Leptin Resistance

The soluble isoform of leptin receptor (sOb-R), secreted by the liver, regulates leptin bioavailability and bioactivity. Its reduced levels in diet-induced obesity (DIO) contributes to hyperleptinemia and leptin resistance, effects that are known to be regulated by the endocannabinoid (eCB)/CB1R system. Here we show that pharmacological activation/blockade as well as genetic overexpression/deletion of hepatic CB1R modulates sOb-R levels and consequently hepatic leptin resistance. Interestingly, peripheral CB1R blockade failed to reverse DIO-induced reduction of sOb-R levels, fat mass, dyslipidemia, and hepatic steatosis in mice lacking C/EBP homologous protein (CHOP), whereas direct activation of CB1R in hepatocytes reduced sOb-R levels in a CHOP-dependent manner. Moreover, CHOP stimulation increased sOb-R expression and release via a direct regulation of its promoter, while CHOP deletion reduced leptin sensitivity. Our findings highlight a novel molecular aspect by which the hepatic eCB/CB1R system involves in the development of hepatic leptin resistance by regulating sOb-R levels via CHOP. SummaryHere we describe a novel molecular aspect by which the hepatic endocannabinoid/CB1R system contributes to hepatic leptin resistance by regulating soluble leptin receptor levels via CHOP.

molecular biology↗