CB2 Receptor Activation Attenuates IL-1β-Induced Inflammatory Transcriptomic Networks in Human Gingival Fibroblasts

Background: Periodontitis is a chronic inflammatory disease characterized by dysregulated host immune responses that drive connective tissue destruction and alveolar bone loss. Human gingival fibroblasts (HGFs) are central regulators of periodontal inflammation through their production of cytokines, chemokines, matrix-remodeling enzymes, and other inflammatory mediators. Although cannabinoid receptor 2 (CB2) activation has demonstrated anti-inflammatory properties, its coordinated effects on multiple inflammatory pathways in gingival fibroblasts remain poorly understood. This study investigated the transcriptomic effects of the selective CB2 agonist HU-308 on IL-1β-induced inflammatory responses in HGFs. Methods: Primary HGFs were divided into untreated controls, IL-1β-stimulated cells (10 ng/mL), and IL-1β-stimulated cells treated with HU-308 (10 μM). Twenty-four hours after stimulation, transcriptome-wide expression profiling was performed using Affymetrix Human Clariom S microarrays, followed by targeted analysis of selected inflammation-related transcriptional domains. Selected transcripts were evaluated within predefined biological domains including cytokines, chemokines, extracellular matrix-associated genes, NO/cGMP-related genes, transporter-associated genes, and GPCR-related transcripts. Gene expression was analyzed using one-way ANOVA with Tukey's post hoc test. Results: IL-1β induced a coordinated inflammatory transcriptional program characterized by increased expression of pro-inflammatory cytokines, chemokines, matrix metalloproteinases, glucose transporter genes, and multiple GPCR-related transcripts, while suppressing collagen-associated genes, NOS3, GPR4, and GPR78. HU-308 broadly attenuated these inflammatory responses by reducing the expression of cytokines, chemokines, matrix metalloproteinases, and several GPCR-related genes while restoring collagen-associated transcripts, nitric oxide signaling components, anti-inflammatory mediators, and selected glucose transporters toward basal levels. Schematic multidimensional visualizations were used to illustrate relative expression patterns among selected transcripts within each functional domain; these visualizations do not represent statistically derived gene networks or molecular interactions. Conclusions: Pharmacological modulation of CB2 by HU-308 exerts broad immunomodulatory effects in IL-1β-stimulated human gingival fibroblasts by coordinately regulating multiple transcriptional networks involved in periodontal inflammation. These findings demonstrate that HU-308 treatment is associated with coordinated modulation of inflammatory, extracellular matrix, nitric oxide, metabolic, and GPCR-associated transcriptional pathways in IL-1β-stimulated HGFs. The results support the hypothesis that CB2 signaling may participate in the broader regulation of these interconnected responses; however, receptor-specific studies using CB2 antagonism or CNR2 knockdown are required to establish causality.