Proteomic Insights Into the Therapeutic Effects of the Camel Milk-Derived Peptide on Insulin Resistance: Modulation of Metabolic, Oxidative, and Signaling Pathways

Insulin resistance (IR) is a hallmark of type 2 diabetes, characterized by disrupted metabolic regulation, oxidative stress, and altered cell signaling. This study employed Data-Independent Acquisition (DIA) quantitative proteomics to profile the proteomic landscape in a cellular model of insulin resistance (MOD) and to evaluate the therapeutic effects of camel milk derived peptide TYYPPQ. Principal Component Analysis (PCA) confirmed distinct proteomic profiles between healthy control (C), MOD, and P2-treated cells, indicating that TYYPPQ induced a partial but significant reprogramming of the insulin-resistant proteome. Enrichment analyses (GO and KEGG) revealed that insulin resistance was characterized by widespread dysregulation, including increased endoplasmic reticulum (ER) stress, oxidative stress, inflammatory pathways, and disruptions in sphingolipid and fructose metabolism. In contrast, TYYPPQ treatment promoted a recovery signature, significantly enriching pathways related to improved insulin signaling (PI3K-Akt, AMPK), regulation of lipolysis, amino acid metabolism, actin cytoskeleton organization, and a marked reduction in ER stress markers. Crucially, these pathway predictions were validated at the molecular level, as qPCR and Western blot analysis confirmed that TYYPPQ effectively restored the expression and phosphorylation of AMPK. Further domain and subcellular localization analyses indicated that insulin resistance disrupted mitochondrial, redox, and protein homeostasis, while P2 treatment counteracted these effects by modulating domains related to mitochondrial function (proline dehydrogenase, cytochrome c oxidase) and restoring protein distribution, notably reducing ER-localized proteins. Collectively, these multi-faceted proteomic findings demonstrate that the peptide TYYPPQ mitigates insulin resistance by coordinately restoring key metabolic and signaling pathways, reducing cellular stress, and improving mitochondrial and cytoskeletal function, highlighting its potential as a therapeutic agent.