Dihydroberberine in metabolic disorders: Bioavailability, molecular mechanisms, toxicology, and future perspectives.

The global prevalence of metabolic diseases, including obesity, type 2 diabetes mellitus (T2DM), and metabolic dysfunction-associated steatotic liver disease (MASLD), continues to rise, representing a major global health threat and economic burden. Dihydroberberine (DHB), a reduced derivative of berberine (BBR), has recently garnered attention due to its superior lipophilicity and intestinal absorption. Pharmacokinetic studies suggested that DHB achieves significantly higher blood concentrations compared to BBR at equivalent doses. This review systematically synthesized the current preclinical evidence regarding the metabolic regulatory mechanisms of DHB. Key pharmacological targets identified in cell and animal models included the activation of AMP-activated protein kinase (AMPK) and glucokinase (GCK), modulation of lipid metabolism, and attenuation of inflammatory and oxidative stress pathways. Furthermore, DHB interacted extensively with the gut microbiota, acting both as a microbial metabolite of BBR and a modulator of microbial composition. Toxicological assessments indicated a favorable safety profile, although potential risks such as hERG channel inhibition required careful evaluation. Importantly, while in vitro and animal studies demonstrated significant metabolic benefits, human clinical trials assessing direct disease outcomes remained highly limited. This review highlighted the pharmacokinetic advantages of DHB and outlined the critical translational gaps that must be addressed in future research.