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Zhang, X.-M.

Publications and source records attributed to Zhang, X.-M..

3 recordsLinked to original sources

Mitochondrial calcium influx-driven bioenergetics in the dopaminergic system selectively enable drug reward

Drugs of abuse hijack the brains reward system, driving pathological dopamine surges that underlie compulsive behavior and addiction. However, directly targeting dopamine signaling for treatment risks disrupting natural reward processes. Here, we identify a bioenergetic mechanism that selectively promotes addiction-related dopamine release and behaviors. Opioids and methamphetamine, but not natural rewards, induce mitochondrial calcium (Ca2+) influx via the mitochondrial calcium uniporter (MCU) in dopaminergic terminals of the nucleus accumbens. Optogenetic stimulation reveals that this mitochondrial Ca2+ influx occurs exclusively during high-intensity dopaminergic neuronal activation. This Ca2+ influx drives rapid ATP production, compensating for energy deficits caused by neuronal hyperactivity and enabling sustained dopamine release. Genetic deletion or pharmacological inhibition of MCU in dopaminergic neurons selectively reduces drug-induced dopamine release and prevents addictive behaviors while sparing natural reward processing in mice. These findings uncover a distinct mitochondrial bioenergetic mechanism underlying drug reward and propose MCU as a promising therapeutic target for addiction treatment.

neuroscience↗

Explore the mechanism of Zigui Yichong Formula in reducing the apoptosis of ovarian granulosa cells in premature ovarian insufficiency based on network pharmacology, molecular docking and cell experiments

ObjectiveThis research is conducted with the objective of exploring the underlying mechanism by which the Zigui Yichong Formula (ZGYCF) diminishes granulosa cell apoptosis in the context of premature ovarian insufficiency (POI), utilizing network pharmacology, molecular docking, and cellular experimentation approaches. MethodsThe active constituents and potential therapeutic targets of the 12 medicinal herbs in ZGYCF, which include Rehmannia glutinosa, Cervus nippon, Cornus officinalis, Ligustrum lucidum, Lycium barbarum, Paeonia lactiflora, Astragalus membranaceus, Codonopsis pilosula, Atractylodes macrocephala, Angelica sinensis, Cyperus rotundus, and Glycyrrhiza uralensis, were identified through searches in the TCMSP, BATMAN, HERB, and ETCM databases. Targets associated with the POI condition were gathered from the OpenTargets, DrugBank, and GeneCards databases. Subsequently, a Venn diagram illustrating the compound-target-disease interaction was generated to derive a set of common targets that bridge the gap between pharmacological and pathological targets. A drug-component-target-disease network diagram was created using Cytoscape 3.9.1. Additionally, protein-protein interaction (PPI) networks were built utilizing the STRING database and visualized with Cytoscape to pinpoint key targets within the overlapping target set. Functional annotation and pathway enrichment analyses, including GO and KEGG pathway analyses, were performed using the clusterProfiler package in R 4.2.1 to investigate the underlying mechanisms by which the drug may influence the disease state. The molecular docking of pivotal active constituents with central targets was carried out using AutoDock Tools. Following this, in vitro studies were executed to corroborate the anticipated mechanisms of action of ZGYCF on POI that were inferred from the network pharmacology analysis. ResultsThe selected active components include quercetin, kaempferol, and {beta}-sitosterol. The core targets identified are Tp53, Bcl-2, and Caspase-3. GO functional and KEGG enrichment analyses indicate that these core targets are primarily enriched in the p53 signaling pathway. Molecular docking results show that quercetin, kaempferol, and {beta}-sitosterol have good binding affinity with TP53, Bcl-2, and Caspase-3. Additionally, in vitro experiments demonstrate that ZGYCF medicated serum can reduce ACR-induced apoptosis in KGN cells, increase Bcl-2 expression, and decrease the expression of p53, Bax, Caspase-3, and the Bcl-2/Bax ratio. ConclusionZGYCF exerts therapeutic effects on POI through multiple targets and pathways, and it may reduce ACR-induced apoptosis in KGN cells by modulating the p53 signaling pathway. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=130 HEIGHT=200 SRC="FIGDIR/small/614279v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@1e55e2forg.highwire.dtl.DTLVardef@18a67d0org.highwire.dtl.DTLVardef@1a596d0org.highwire.dtl.DTLVardef@503fde_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Berberine is a novel mitochondrial calcium uniporter (MCU) inhibitor that disrupts MCU-EMRE assembly

The mitochondrial calcium uniporter (MCU) complex mediates Ca2+ entry into mitochondrial, which plays a crucial role in regulating cellular energy metabolism and apoptosis. Dysregulation of MCU is implicated in various diseases, such as neurodegenerative disorders, cardiac diseases and cancer. Despite its importance, developing specific and clinically viable MCU inhibitors has been challenging. Here, we identify Berberine, a well-established drug with a documented safety profile, as a potent MCU inhibitor through a virtual screening of an FDA-approved drug library. Berberine localizes within mitochondria and directly binds to the juxtamembrane loop domain of MCU. This binding disrupts the interaction of MCU with its essential regulator, EMRE, thereby inhibiting rapid Ca2+ entry into the mitochondria. Notably, Berberine pretreatment reduces mitochondrial Ca2+ overload and mitigate ischemia/reperfusion-induced myocardial injury in mice. Our findings establish Berberine as a potent MCU inhibitor, offering a safe therapeutic strategy for diseases associated with dysregulated mitochondrial calcium homeostasis.

cell biology↗