Altered synaptic currents, mitophagy, mitochondrial dynamics in Alzheimer's disease models and therapeutic potential of Dengzhan Shengmai capsules intervention.

Emerging research suggests a potential association of progression of Alzheimer's disease (AD) with alterations in synaptic currents and mitochondrial dynamics. However, the specific associations between these pathological changes remain unclear. In this study, we utilized Aß42-induced AD rats and primary neural cells as in vivo and in vitro models. The investigations included behavioural tests, brain magnetic resonance imaging (MRI), liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis, Nissl staining, thioflavin-S staining, enzyme-linked immunosorbent assay, Golgi-Cox staining, transmission electron microscopy (TEM), immunofluorescence staining, proteomics, adenosine triphosphate (ATP) detection, mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) assessment, mitochondrial morphology analysis, electrophysiological studies, Western blotting, and molecular docking. The results revealed changes in synaptic currents, mitophagy, and mitochondrial dynamics in the AD models. Remarkably, intervention with Dengzhan Shengmai (DZSM) capsules emerged as a pivotal element in this investigation. Aß42-induced synaptic dysfunction was significantly mitigated by DZSM intervention, which notably amplified the frequency and amplitude of synaptic transmission. The cognitive impairment observed in AD rats was ameliorated and accompanied by robust protection against structural damage in key brain regions, including the hippocampal CA3, primary cingular cortex, prelimbic system, and dysgranular insular cortex. DZSM intervention led to increased IDE levels, augmented long-term potential (LTP) amplitude, and enhanced dendritic spine density and length. Moreover, DZSM intervention led to favourable changes in mitochondrial parameters, including ROS expression, MMP and ATP contents, and mitochondrial morphology. In conclusion, our findings delved into the realm of altered synaptic currents, mitophagy, and mitochondrial dynamics in AD, concurrently highlighting the therapeutic potential of DZSM intervention.

Verticillium dahliae Asp1 regulates the transition from vegetative growth to asexual reproduction by modulating microtubule dynamic organization.

Verticillium dahliae is a devastating pathogenic fungus that causes severe vascular wilts in more than 400 dicotyledonous plants. The conidiation of V. dahliae in plant vascular tissues is the key strategy for its adaptation to the nutrient-poor environment and is required for its pathogenicity. However, it remains unclear about the regulatory mechanism of conidium production of V. dahliae in vascular tissues. Here, we found that VdAsp1, encoding an inositol polyphosphate kinase, is indispensable for the pathogenicity of V. dahliae. Loss of VdAsp1 function does not affect the invasion of the host, but it impairs the colonization and proliferation in vascular tissues. The ΔVdAsp1 mutant shows defective initiation of conidiophore formation and reduced expression of genes associated with the central developmental pathway. By live-cell imaging, we observed that some of ΔVdAsp1 mutant hyphae are swollen, and microtubule arrangements at the apical region of these hyphae are disorganized. These results indicate that VdAsp1 regulates the transition from vegetative growth to asexual reproduction by modulating microtubule dynamic organization, which is essential for V. dahliae to colonize and proliferate in vascular tissues. These findings provided a potential new direction in the control of vascular wilt pathogen by targeting conidium production in vascular tissues.

Transcriptional regulation of CYP19A1 expression in chickens: ESR1, ESR2 and NR5A2 form a functional network.

Aromatase, encoded by CYP19A1, is responsible for the conversion of androgen to estrogen, which plays a vital role in the development and function of the ovary and functions in many other physiological processes in both sexes. Instead of being expressed in ovarian granulosa cells, as in mammals, CYP19A1 is expressed in chickens in the theca cells of ovarian follicles, and the mechanism of CYP19A1 expression regulation remains unknown. Here, using immunofluorescence and western blotting assay, we first confirmed that CYP19A1 and FOXL2 (Forkheadbox L2) were coexpressed in pre-granulosa cells of female chicken embryonic gonads, while FOXL2 did not affect aromatase expression at embryonic stages. Second, our research showed that CYP19A1, ESR1 (estrogen receptor alpha), ESR2 (estrogen receptor beta) and NR5A2 (liver receptor homologue-1) were coexpressed in the theca cell layers of chicken small yellow follicles. There was cross-talk between CYP19A1 and candidate transcription factors (ESR1, ESR2 and NR5A2), which was identified by generating a reliable theca cell culture model. Using luciferase assays in theca cells and chicken embryonic fibroblast (DF-1) cells, the results suggested that ESR1 and NR5A2 had potential effects on CYP19A1 promoter activity in chickens. Overexpression of ESR1, ESR2 and NR5A2 in chicken embryonic fibroblast (DF-1) cells upregulated the protein expression of CYP19A1, mutually restricted each other and formed a potential regulatory network to coordinate the expression of CYP19A1. To conclude, our results indicated that FOXL2 cannot regulate the expression of CYP19A1 at chicken embryonic stages and after sexual maturity, ESR1, ESR2 and NR5A2 form a functional network to affect the expression of CYP19A1. These results laid a foundation for further research on the transcriptional regulation of chicken aromatase.

Cytochrome P450 Omega-Hydroxylase 4a14 Attenuates Cholestatic Liver Fibrosis.

BACKGROUND: Cholestasis is a pathological condition involving obstruction of bile secretion and excretion that results in hepatotoxicity, inflammation, fibrosis, cirrhosis, and eventually liver failure. Common bile duct ligation (BDL) model is a well-established murine model to mimic cholestatic liver fibrosis. We previously reported that cytochrome P450 omega-hydroxylase 4a14 (Cyp4a14) plays an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD)-related fibrosis. The goal of this study was to determine the role of Cyp4a14 in cholestatic-induced liver fibrosis. METHODS: C57BL/6 mice were subjected to BDL for 14 days, and Cyp4a14 mRNA and protein levels were examined and compared with those of the sham group. Cyp4a14 knockout mice and adeno-associated virus (AAV)-mediated overexpression of Cyp4a14 in C57BL/6 mice underwent BDL and liver histology, and key fibrosis markers were examined. RESULTS: Both hepatic Cyp4a14 mRNA and protein levels were markedly reduced in BDL liver compared with the time-matched sham group. Cyp4a14 gene-deficient mice aggravates whereas its overexpression alleviates BDL-induced hepatic fibrosis, which were determined by liver function, liver histology, and levels of key fibrotic markers including α-smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1), and collagen 1a2 (Col1a2). CONCLUSION: Cyp4a14 exerts a contrasting role in different hepatic fibrosis models. Strategies that enhance Cyp4a14 activity may be potential strategies to cholestatic related liver fibrosis.