Type 2 diabetes mellitus (T2D) affects hundreds of millions worldwide, with recent estimates indicating approximately 589 million adults living with diabetes, most with type 2 disease. Beyond classical insulin signaling pathways, increasing evidence implicates altered protein glycosylation in metabolic dysfunction. The solute carrier 35 (SLC35) family of nucleotide sugar transporters mediates the import of activated sugars into the endoplasmic reticulum and Golgi lumen, thereby influencing global glycosylation patterns. Dysregulation of these transporters can perturb glucose homeostasis, insulin responsiveness, and nutrient-sensing pathways through changes in glycosylation flux. In this review, we dissect the molecular mechanisms by which these transporters modulate glucose homeostasis, insulin signaling pathways, protein O-GlcN acylation, and broader glycosylation processes. We integrate findings from human genetic studies, rodent models, and in vitro functional analyses to characterize how altered SLC35 activity is associated with T2D and metabolic syndrome. Four members demonstrate particularly compelling evidence: SLC35B4 modulates hepatic glucose metabolism, SLC35D3 mutations impair dopaminergic signaling and energy balance, and SLC35F3 variants interact with high-carbohydrate intake to increase metabolic-syndrome risk. SLC35A3, though less studied, may influence glycosylation-dependent insulin signaling through its role in N-glycan biosynthesis. Beyond these characterized transporters, this review identifies potential metabolic roles for understudied family members, suggesting broader implications across the entire SLC35 family. We also discuss how such alterations can lead to disrupted hexosamine flux, impaired glycoprotein processing, aberrant cellular signaling, and micronutrient imbalances. Finally, we evaluate the therapeutic potential of targeting SLC35 transporters, outlining both opportunities and challenges in translating these insights into novel T2D treatments.

Idiopathic pulmonary fibrosis (IPF), hypersensitivity pneumonitis (HP), and systemic sclerosis-associated interstitial lung disease (SSc-ILD) share the same structural outcome: extracellular matrix (ECM) deposition. Whether this shared endpoint reflects shared or distinct molecular programs remains unresolved. Differential expression results from four GEO datasets representing IPF, HP, non-IPF ILD, and SSc-ILD were intersected with the 1027-gene human matrisome masterlist and classified by threshold-defined disease preference. All four diseases shared a 21-gene upregulated matrisome core, and the matrisome fraction rose with cross-disease sharing, from 4.3% of single-disease upregulated genes to 45.7% of genes upregulated in all four (significant Cochran–Armitage trend), and the enrichment persisted when any single cohort was removed. Apparent disease preference was largely attributable to unequal statistical power: of 29 genes measurable in all four datasets, 24 showed a concordant sub-threshold effect in at least one comparator disease. Category composition of the threshold-defined signatures did not differ significantly between diseases, and the exploratory pathway panel is reported within diseases only, because significance scales with cohort size. In a within-cohort comparison of IPF with chronic HP in GSE150910, with platform, cohort, and control population held constant, matrisome genes were over-represented among the 2732 genes separating the two diseases, and 205 matrisome genes distinguished them. Fibrosing ILDs share a cross-cohort ECM core, and the apparent disease preference of the remaining signatures largely reflects differences in statistical power between cohorts. Disease-preferential matrisome expression is nonetheless detectable when disease and study are not confounded, so the limitation lies in threshold-based cross-study intersection rather than in the matrisome compartment itself.