Natural Product Driven Activation of UCP1 and Tumor Metabolic Suppression: Integrating Thermogenic Nutrient Competition with Cancer Metabolic Reprogramming.

Metabolic reprogramming allows cancer cells to proliferate rapidly, survive nutrient limitation, and resist stress, making tumor metabolism an important therapeutic target. However, pharmacological inhibition of metabolic enzymes often causes systemic toxicity and compensatory pathway activation. To overcome these limitations, recent studies have highlighted an alternative host-centered strategy based on increasing systemic energy expenditure. Recent studies highlight an alternative strategy in which the host increases energy expenditure through uncoupling protein 1 (UCP1) dependent thermogenesis, thereby lowering systemic glucose, fatty acid, and nucleotide availability for tumors. Engineered beige adipocytes overexpressing UCP1, PR domain-containing protein 16 (PRDM16), or peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A/PGC1A) suppress tumor growth through nutrient competition, suggesting that activating endogenous UCP1 may provide a non-genetic and physiologically aligned anticancer approach. Building on this concept, natural products such as polyphenols, terpenoids, alkaloids, and carotenoids have emerged as promising UCP1 activators that stimulate beige and brown adipocyte thermogenesis through pathways involving AMP-activated protein kinase (AMPK), sirtuin 1 (SIRT1), PGC1A, PRDM16, and mitochondrial biogenesis. In parallel, computational studies further indicate that several plant-derived compounds bind directly to the central cavity of UCP1 with high affinity, offering structural support for their thermogenic action. Importantly, many of these compounds also inhibit cancer cell intrinsic metabolism by reducing glycolysis, oxidative phosphorylation, lipid synthesis, and amino acid dependent anaplerosis. This review integrates UCP1 biology, natural product mediated thermogenesis, molecular docking evidence, and tumor metabolic suppression, proposing a unified framework in which natural compounds impose coordinated metabolic pressure on cancer through both adipocyte-driven nutrient competition and direct inhibition of tumor metabolism.