Danhong injection alleviates cerebral ischemia-reperfusion injury by inhibiting autophagy through miRNA-132-3p/ATG12 signal axis.

ETHNOPHARMACOLOGICAL RELEVANCE: Danhong injection (DHI) is a renowned traditional Chinese medicine often used clinically to treat cardiovascular and cerebrovascular diseases. Studies have shown that DHI can significantly alter microRNA (miRNA) expression in the brain tissue. Therefore, exploring specific miRNAs' regulatory mechanisms during treatment with DHI is essential. AIM OF THE STUDY: To investigate DHI's regulatory mechanism on cerebral autophagy in rats with cerebral ischemia-reperfusion injury (CIRI). MATERIAL AND METHODS: Rats were randomly divided into the sham, middle cerebral artery occlusion (MCAO) model, and DHI-treatment groups. The extent of brain damage was evaluated using triphenyl tetrazolium chloride and hematoxylin-eosin staining. Hippocampal cell autophagy was observed using transmission electron microscopy. Autophagy-related proteins were analyzed using western blotting. Differentially expressed miRNAs were screened using high-throughput and real-time quantitative reverse transcription PCR. The relationship between miR-132-3p and ATG12 was confirmed using a dual-luciferase assay. The miR-132-3p mimics and inhibitors were transfected into PC12 cells subjected to oxygen-glucose deprivation (OGD) in vitro and MCAO model rats in vivo. RESULTS: DHI significantly altered the miRNA expression profile in rat brain tissues. The pathological changes in the brain tissues were improved, and the autophagic hippocampal cell vehicles were significantly reduced after DHI treatment. miRNA-132-3p, one of the miRNAs with a significantly different expression, was screened. Kyoto Encyclopedia of Genes and Genomes signal pathway analysis showed that its target genes were closely related to autophagy. Western blotting revealed that the p-PI3K, p-AKT, and mTOR expression increased significantly; AMPK, ULK1, ATG12, ATG16L1, and LC3II/I were downregulated in the DHI group. Dual-luciferase reporter gene experiments showed that miRNA-132-3p could target the ATG12 3'-UTR region directly. In vitro, miRNA-132-3p had a protective effect on OGD/R-induced oxidative stress injury in PC12 cells, improving cell viability, and affecting the expression of autophagy pathway-related proteins. In vivo transfection experiments showed that miR-132-3p could regulate ATG12 expression in CIRI rats' lateral brain tissue, affecting the autophagy signaling pathway. miR-132-3p overexpression reduces CIRI-induced autophagy and protects neurons. CONCLUSION: This study showed that DHI inhibits neuronal autophagy after cerebral ischemia-reperfusion. This may have resulted from miR-132-3p targeting ATG12 and regulating the autophagy signaling pathway protein expression.

Functional Analysis of Autophagy-Related Gene ATG12 in Potato Dry Rot Fungus Fusarium oxysporum.

Autophagy is an intracellular process in all eukaryotes which is responsible for the degradation of cytoplasmic constituents, recycling of organelles, and recycling of proteins. It is an important cellular process responsible for the effective virulence of several pathogenic plant fungal strains, having critical impacts on important crop plants including potatoes. However, the detailed physiological mechanisms of autophagy involved in the infection biology of soil-borne pathogens in the potato crop needs to be investigated further. In this study, the autophagy-related gene, FoATG12, in potato dry rot fungus Fusarium oxysporum was investigated by means of target gene replacement and overexpression. The deletion mutant ∆FoATG12 showed reduction in conidial formation and exhibited impaired aerial hyphae. The FoATG12 affected the expression of genes involved in pathogenicity and vegetative growth, as well as on morphology features of the colony under stressors. It was found that the disease symptoms were delayed upon being inoculated by the deletion mutant of FoATG12 compared to the wild-type (WT) and overexpression (OE), while the deletion mutant showed the disease symptoms on tomato plants. The results confirmed the significant role of the autophagy-related ATG12 gene in the production of aerial hyphae and the effective virulence of F. oxysporum in the potato crop. The current findings provid an enhanced gene-level understanding of the autophagy-related virulence of F. oxysporum, which could be helpful in pathogen control research and could have vital impacts on the potato crop.

Activation of mitochondrial TUFM ameliorates metabolic dysregulation through coordinating autophagy induction.

Disorders of autophagy, a key regulator of cellular homeostasis, cause a number of human diseases. Due to the role of autophagy in metabolic dysregulation, there is a need to identify autophagy regulators as therapeutic targets. To address this need, we conducted an autophagy phenotype-based screen and identified the natural compound kaempferide (Kaem) as an autophagy enhancer. Kaem promoted autophagy through translocation of transcription factor EB (TFEB) without MTOR perturbation, suggesting it is safe for administration. Moreover, Kaem accelerated lipid droplet degradation in a lysosomal activity-dependent manner in vitro and ameliorated metabolic dysregulation in a diet-induced obesity mouse model. To elucidate the mechanism underlying Kaem's biological activity, the target protein was identified via combined drug affinity responsive target stability and LC-MS/MS analyses. Kaem directly interacted with the mitochondrial elongation factor TUFM, and TUFM absence reversed Kaem-induced autophagy and lipid degradation. Kaem also induced mitochondrial reactive oxygen species (mtROS) to sequentially promote lysosomal Ca2+ efflux, TFEB translocation and autophagy induction, suggesting a role of TUFM in mtROS regulation. Collectively, these results demonstrate that Kaem is a potential therapeutic candidate/chemical tool for treating metabolic dysregulation and reveal a role for TUFM in autophagy for metabolic regulation with lipid overload.

To Elucidate the Inhibition of Excessive Autophagy of Rhodiola crenulata on Exhaustive Exercise-Induced Skeletal Muscle Injury by Combined Network Pharmacology and Molecular Docking.

Autophagy can remodel skeletal muscle in response to exercise. However, excessive autophagy can have adverse effects on skeletal muscle. Although Rhodiola crenulata (R. crenulata) is thought to regulate autophagy, its active ingredients and mechanisms of action remain unclear. In this study, molecular docking and network pharmacology were used to screen for autophagy-related targets of R. crenulata. Subsequently, protein-protein interaction (PPI) analysis was used to find the relationships between the inverse docking targets and autophagy-related targets and therefore highlight the key targets. And then the Database for Annotation, Visualization, and Integrated Discovery (DAVID) database was recruited to explain the functions and enrichment pathways of the target proteins. Finally, the potential targets were validated by immunohistochemistry of a mouse model of exhaustive exercise-induced skeletal muscle injury. We found a network of 15 major constituents of R. crenulata with 30 autophagy-related and 105 inverse-docking targets by molecular docking and network pharmacology. The results of PPI analysis indicated that 16 inverse-docking targets interacted 8 autophagy-related proteins. Further pathway analysis showed that R. crenulata could regulate exercise-induced skeletal muscle autophagy through mammalian target of rapamycin (mTOR), AMP activated protein kinase (AMPK) and Forkhead box protein O (FoxO). The results of our animal experiments indicated that R. crenulata could suppress the expression of Ubiquitin-like protein ATG12 (ATG12), Beclin-1 (BECN1), and Serine/threonine-protein kinase ULK1 (ULK1), while increasing the expression of MTOR, NAD-dependent protein deacetylase sirtuin-1 (SIRT1), and Microtubule-associated protein tau (MAPT). In conclusion, this study demonstrated that R. crenulata may protect skeletal muscle injury induced by exhaustive exercise via regulating the mTOR, AMPK, and FoxO singling pathway.