Background. Mitochondrial dysfunctions play a pivotal role in cerebral ischemia‐reperfusion (I/R) injury. Although mitochondrial transplantation has been recently explored for the treatment of cerebral I/R injury, the underlying mechanisms and fate of transplanted mitochondria are still poorly understood. Methods. Mitochondrial morphology and function were assessed by fluorescent staining, electron microscopy, JC‐1, PCR, mitochondrial stress testing, and metabolomics. Therapeutic effects of mitochondria were evaluated by cell viability, reactive oxygen species (ROS), and apoptosis levels in a cellular hypoxia‐reoxygenation model. Rat middle cerebral artery occlusion model was applied to assess the mitochondrial therapy in vivo. Transcriptomics was performed to explore the underlying mechanisms. Mitochondrial fate tracking was implemented by a variety of fluorescent labeling methods. Results. Neuro‐2a (N2a) cell‐derived mitochondria had higher mitochondrial membrane potential, more active oxidative respiration capacity, and less mitochondrial DNA copy number. Exogenous mitochondrial transplantation increased cellular viability in an oxygen‐dependent manner, decreased ROS and apoptosis levels, improved neurobehavioral deficits, and reduced infarct size. Transcriptomic data showed that the differential gene enrichment pathways are associated with metabolism, especially lipid metabolism. Mitochondrial tracking indicated specific parts of the exogenous mitochondria fused with the mitochondria of the host cell, and others were incorporated into lysosomes. This process occurred at the beginning of internalization and its efficiency is related to intercellular connection. Conclusions. Mitochondrial transplantation may attenuate cerebral I/R injury. The mechanism may be related to mitochondrial component separation, altering cellular metabolism, reducing ROS, and apoptosis in an oxygen‐dependent manner. The way of isolated mitochondrial transfer into the cell may be related to intercellular connection.

Engineered extracellular vesicles (EVs) are considered excellent delivery vehicles for a variety of therapeutic agents, including nucleic acids, proteins, drugs, and nanomaterials. Recently, several studies have indicated that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated 9 (Cas9) delivered by EVs enable efficient DNA editing. However, an RNA editing tool delivered by EVs is still unavailable. Here, a signal peptide‐optimized and EVs‐delivered guide RNA (gRNA) and CRISPR/CasRx (Cas13d) system capable of rapidly inhibiting the expression of targeted genes with quick catabolism after performing their functions is developed. EVs with CRISPR/CasRx and tandem gRNAs targeting pivotal cytokines are further packed whose levels increase substantially over the course of acute inflammatory diseases and find that these engineered EVs inhibit macrophage activation in vitro. More importantly, this system attenuates lipopolysaccharide (LPS)‐triggered acute lung injury and sepsis in the acute phase, mitigating organ damage and improving the prognosis in vivo. In summary, a potent tool is provided for short‐acting RNA editing, which could be a powerful therapeutic platform for the treatment of acute diseases.

Background: The transient receptor potential vanilloid 1 (TRPV1) is a cation channel implicated in neurological disorders. Although TRPV1 activation contributes to intracerebral hemorrhage (ICH) pathology, its microglia‐specific role and underlying mechanisms remain poorly defined. This study investigates how microglial TRPV1 influences ICH injury. Methods: We utilized a mouse ICH model alongside microglia‐specific TRPV1 knockout mice, BV2 cells, and primary microglial cultures. Interventions included TRPV1 antagonist capsazepine (CPZ), agonist capsaicin (CAP), microglial depletion agent PLX5622, and TRPV1 knockdown. Outcomes were assessed using immunofluorescence, behavioral tests, Western blot, magnetic resonance imaging (MRI), and transmission electron microscopy (TEM). Results: TRPV1 expression was significantly upregulated post‐ICH, primarily in microglia. TRPV1 blockade with CPZ treatment reduced hematoma volume, brain edema, neuronal apoptosis, and improved neurological function, whereas CAP exacerbated injury. These benefits were replicated in microglia‐specific TRPV1 knockout mice. Mechanistically, CPZ shifted microglia from a pro‐inflammatory (iNOS+) to a regulatory (Arg1+) phenotype and suppressed excessive mitophagy via the Ca ²⁺ ‐AMPK‐PINK1 pathway. Conclusion: TRPV1 activation in microglia exacerbates ICH injury by promoting inflammation and disruptive mitophagy. Targeted inhibition of microglial TRPV1 represents a promising therapeutic strategy for ICH.