Effects of zacopride and multidimensional impacts of cross-kingdom symbiosis: gut microbiota modulates coronary microvascular dysfunction via the chlorophyll/heme-tryptophan metabolic axis.

backgroundCoronary Microvascular Dysfunction (CMD) represents a critical pathological substrate for ischemic heart disease and is strongly associated with major adverse cardiovascular events. Zacopride, known for its dual cardiovascular regulatory properties targeting the 5-HT

methodsSixty Sprague-Dawley rats were randomized into three groups: coronary microvascular dysfunction (CMD), healthy control (NC), and Zacopride intervention (ZAC). CMD and ZAC groups received high-fat diet plus streptozotocin (STZ, 35 mg/kg) for modeling. ZAC rats were orally administered 5 mg/kg Zacopride daily for 7 days. Transthoracic Doppler echocardiography measured left anterior descending coronary artery resting/stress peak flow velocity and coronary flow reserve (CFR). Ileocecal contents underwent bacterial-fungal metagenomic sequencing to identify differential metabolic pathways. Spearman's correlation assessed cross-kingdom ecological interactions. Nine machine learning algorithms constructed classification models, with Random Forest (RF) and an optimal model identifying key genera. Linear Discriminant Analysis Effect Size validated microbial biomarkers.

resultsZacopride partially restored the CFR in CMD rats, demonstrating a therapeutic effect, and exerted a beneficial influence on the structure and diversity of the gut microbiota. The CMD state significantly reduced the expression levels of the Chlorophyll a and tryptophan metabolic pathways in the gut microbiota. Zacopride specifically restored the Chlorophyll a pathway but did not significantly recover the tryptophan metabolic pathway. RF and Elastic Net (ENET) identified JC017, Chromelosporium, and Barnesiella as biomarker microbiota for CMD. Notably, JC017 primarily mediate the therapeutic effects of Zacopride via direct or indirect modulation of the Chlorophyll a metabolic pathway. Chromelosporium, acting as an interactive hub between fungi and bacteria, formed a cross-kingdom symbiotic relationship with Bradyrhizobium. Additionally, the reduction in Barnesiella abundance constitutes a distinctive feature of gut microbial dysbiosis in CMD.

conclusionThis study provides the first evidence that the gut microbiota modulates the pathogenesis of CMD through the "chlorophyll/heme-tryptophan metabolic axis." Furthermore, we demonstrate that Zacopride exerts therapeutic effects by remodeling microbiota-host interactions and regulating this metabolic axis, revealing a novel mechanistic link between microbial metabolism and CMD progression.