Abstract
Background
Alzheimer's Disease (AD) is a serious neurodegenerative disease and there is currently no effective treatment for AD progression. The use of TCM as a potential treatment strategy ...for AD is an evolving field of investigation. Asafoetida (ASF), an oleo-gum-resin isolated from Ferula assa-foetida root, has been proven to possess antioxidative potential and neuroprotective effects, which is closely associated with the neurological disorders. However, the efficacy and further mechanisms of ASF in AD experimental models are still unclear.
Methods
A cognitive impairment of mouse model induced by scopolamine was established to determine the neuroprotective effects of ASF in
vivo
, as shown by behavioral tests, biochemical assays, Nissl staining, TUNEL staining, Immunohistochemistry, western blot and qPCR. Furthermore, the PC12 cells stimulated by H
2
O
2
were applied to explore the underlying mechanisms of ASF-mediated efficacy. Then, the UPLCM analysis and integrated network pharmacology approach was utilized to identified the main constitutes of ASF and the potential target of ASF against AD, respectively. And the main identified targets were validated in
vitro
by western blot, qPCR and immunofluorescence staining.
Results
In
vivo
, ASF treatment significantly ameliorated cognitive impairment induced by scopolamine, as evidenced by improving learning and memory abilities, and reducing neuronal injury, cholinergic system impairment, oxidative stress and apoptosis in the hippocampus of mice. In
vitro
, our results validated that ASF can dose-dependently attenuated H
2
O
2
-induced pathological oxidative stress in PC12 cells by inhibiting ROS and MDA production, as well as promoting the activities of SOD, CAT, GSH. We also found that ASF can significantly suppressed the apoptosis rate of PC12 cells increased by H
2
O
2
exposure, which was confirmed by flow cytometry analysis. Moreover, treatment with ASF obviously attenuated H
2
O
2
-induced increase in caspase-3 and Bax expression levels, as well as decrease in Bcl-2 protein expression. KEGG enrichment analysis indicated that the PI3K/Akt/GSK3β/Nrf2 /HO-1pathway may be involved in the regulation of cognitive impairment by ASF. The results of western blot, qPCR and immunofluorescence staining of vitro assay proved it.
Conclusions
Collectively, our work first uncovered the significant neuroprotective effect of ASF in treating AD in
vivo
. Then, we processed a series of vitro experiments to clarify the biological mechanism action. These data demonstrate that ASF can inhibit oxidative stress induced neuronal apoptosis to foster the prevention of AD both in
vivo
and in
vitro
, and it may exert the function of inhibiting AD through PI3K/Akt/GSK3β/Nrf2/HO-1pathway.
•ESI and APCI were evaluated for LC–MS determination of sulfonate ester PGIs.•Twelve sulfonate esters were systematically studied and APCI proved better than ESI.•Stable precursor ions M-alkyl− and ...corresponding product ions produced in APCI.•More adduct ions competed abundance in ESI which diminished the sensitivity.•Good precision and low limits of detection were obtained using APCI in SRM mode.
Two ionization techniques for liquid chromatography–mass spectrometry (LC–MS) determination of sulfonate ester potentially genotoxic impurities (PGIs) were evaluated. Twelve PGIs including methyl, ethyl, propyl and isopropyl esters of methanesulfonate, benzenesulfonate and p-toluenesulfonate were studied in this research. Electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources were compared in terms of performance and quality parameters for detection of the twelve PGIs. Their mass spectra obtained by APCI and ESI were very different in both fragment ions and relative abundances. In APCI negative ion mode the twelve sulfonate esters showed their stable precursor ions of M-alkyl−, which readily yielded product ions of M-alkyl-CH3− (for aliphatic sulfonate esters) or M-alkyl-SO2− (for aromatic sulfonate esters) with collision-induced dissociation (CID) applied; and working in selected reaction monitoring (SRM) mode has allowed limits of detection to be decreased. In the case of ESI ionization, these compounds showed their precursor ions M+H+, but their abundance was easily competed by formation of ions M+NH4+ and/or M+Na+, which led to poor analytical sensitivity and reproducibility. Although mobile phase additives could enhance the responses of adduct ions like M+NH4+ and M+Na+, no improvement was obtained when using SRM mode. Twelve sulfonate esters were systematically compared and APCI was shown to be a better ionization technique for rapid and sensitive determination of these PGIs. Performance of the developed approach for rapid determination of 12 PGIs was also evaluated. Quality parameters were established and good precision (relative standard deviations <8%) and very low limits (2–4ng/mL) of detection were obtained, mainly when using APCI in SRM mode.
Recent evidence suggests that endoplasmic reticulum (ER) stress signaling through glycogen synthase kinase (GSK)-3α/β is involved in the activation of pro-atherosclerotic processes. In this study, we ...examined the effects of small molecules that interfere with ER stress-GSK3α/β signaling on the progression and regression of atherosclerosis in a mouse model.
To examine atherosclerotic progression, low-density lipoprotein receptor deficient (Ldlr−/−) mice were placed on a high-fat diet (HFD) and treated with the chemical chaperone, 4-phenylbutyrate (4PBA, 3.8 g/L drinking water), or the GSK3α/β inhibitor, valproate (VPA, 625 mg VPA/kg diet), for 10 weeks. To examine potential effects on atherosclerotic regression, 4 week old Ldlr−/− mice were placed on a HFD for 16 weeks. Subsets of mice were harvested at this time or switched to a chow (low fat) diet, or a chow diet with 4PBA or VPA treatment for 4 weeks.
In the progression model, the 4PBA- and VPA-treated mice had significantly reduced lesion and necrotic core size. Treatments had no effect on metabolic parameters, including plasma and hepatic lipid levels, or plaque composition. In the regression model, mice with 4PBA or VPA treatment showed no alterations in lesion size, but the lesions had significantly smaller necrotic cores, increased vascular smooth muscle cell content, and increased collagen content. These features are consistent with more stable plaques.
The pharmacological attenuation of ER stress or inhibition of GSK3α/β impedes the development of atherosclerosis in Ldlr−/− mice and appears to promote the stabilization of existing lesions.
•Ldlr−/− mice are used to investigate atherosclerotic progression and regression.•4-phenylbutyrate (4-PBA) or valproate (VPA) treatment attenuates atherosclerotic development.•Treatments can inhibit the progression of existing atherosclerotic lesions.•Lesions are stabilized upon 4 weeks of 4-PBA or VPA treatment, but do not regress or reduce in lesion size.
Isatropolone A and C, produced by Streptomyces sp. CPCC 204095, belong to an unusual class of non-benzenoid aromatic compounds and contain a rare seven-membered ring structure. Isatropolone A ...exhibits potent activity against Leishmania donovani, comparable to the only oral drug miltefosine. However, its variably low productivity represents a limitation for this lead compound in the future development of new anti-leishmaniasis drugs to meet unmet clinical needs.
Here we first elucidated the regulatory cascade of biosynthesis of isatropolones, which consists of two SARP family regulators, IsaF and IsaJ. Through a series of in vivo and in vitro experiments, IsaF was identified as a pathway-specific activator that orchestrates the transcription of the gene cluster essential for isatropolone biosynthesis. Interestingly, IsaJ was found to only upregulate the expression of the cytochrome P450 monooxygenase IsaS, which is crucial for the yield and proportion of isatropolone A and C. Through targeted gene deletions of isaJ or isaS, we effectively impeded the conversion of isatropolone A to C. Concurrently, the facilitation of isaF overexpression governed by selected promoters, prompted the comprehensive activation of the production of isatropolone A. Furthermore, meticulous optimization of the fermentation parameters was conducted. These strategies culminated in the attainment of an unprecedented maximum yield-980.8 mg/L of isatropolone A-achieved in small-scale solid-state fermentation utilizing the genetically modified strains, thereby establishing the highest reported titer to date.
In Streptomyces sp. CPCC 204095, the production of isatropolone A and C is modulated by the SARP regulators IsaF and IsaJ. IsaF serves as a master pathway-specific regulator for the production of isatropolones. IsaJ, on the other hand, only dictates the transcription of IsaS, the enzyme responsible for the conversion of isatropolone A and C. By engineering the expression of these pivotal genes, we have devised a strategy for genetic modification aimed at the selective and high-yield biosynthesis of isatropolone A. This study not only unveils the unique regulatory mechanisms governing isatropolone biosynthesis for the first time, but also establishes an essential engineering framework for the targeted high-level production of isatropolone A.
Allergic asthma is a prevalent form of asthma that is characterized primarily by airway inflammation. Jiegeng decoction (JGT) is a traditional Chinese herbal formula known for its anti-inflammatory ...properties and has been used to treat respiratory diseases for centuries. This study aimed to investigate the biological effects and mechanisms of action of JGT in improving allergic asthma. An experimental allergic asthma mouse model was established using ovalbumin. The results showed that JGT significantly improved inflammation cell infiltration in the lung tissue of allergic asthmatic mice and the inflammatory environment of Th2 cells in the bronchoalveolar lavage fluid while also reducing serum IgE levels. Subsequently, 38 components of JGT were identified through liquid chromatography–mass spectrometry. Network pharmacology revealed that regulating inflammation and immune responses is the primary biological process by which JGT improves allergic asthma, with Th2 cell differentiation and the JAK-STAT signaling pathway being the key mechanisms of action. Finally, qPCR, flow cytometry, and Western blotting were used to validate that JGT inhibited Th2 cell differentiation by blocking the JAK1-STAT6 signaling pathway in CD4+ T cells, ultimately improving allergic asthma. This study provides a novel perspective on the therapeutic potential of JGT in the treatment of allergic asthma.
High-resolution remote sensing imagery comprises spatial structure features of multispectral bands varying in scale, color, and shape. These heterogeneous geographical features introduce grave ...challenges to the fine segmentation required for classification applications in remote sensing imagery, where direct application of traditional image classification models fails to deliver optimal results. To overcome these challenges, a multispectral, multi-label model, MMDL-Net, has been developed. This model is integrated with the multi-label BigEarthNet dataset, primarily employed for land cover classification research in remote sensing imagery, with each image composed of 13 spectral bands and spatial resolutions of 10 m, 20 m, and 60 m. To effectively utilize the information across these bands, a multispectral stacking module has been introduced to concatenate this spectral information. To proficiently process three distinct large-scale remote sensing image datasets, a multi-label classification module has been incorporated for training and inference. To better learn and represent the intricate features within the images, a twin-number residual structure has been proposed. The results demonstrate that the MMDL-Net model achieves a top accuracy of 83.52% and an F1 score of 77.97%, surpassing other deep learning models and conventional methods, thereby exhibiting exceptional performance in the task of multispectral multi-label classification of remote sensing imagery.
Pear Valsa canker is a fungal trunk disease caused by Valsa pyri. Phenolic compounds are ubiquitous in plants and usually contribute to plant resistance against biotic stress. To investigate the ...association between phenolic compounds and level of resistance to V. pyri, we quantified the contents of individual phenolic compounds in the cortex and phloem of stems from 8 cultivars of Pyrus bretschneideri. Significant variation in the levels of all compounds was found among the cultivars. Correlation analysis revealed an inverse correlation between levels of arbutin and gallic acid with the degree of canker resistance. This suggested that these phenolic compounds are beneficial to V. pyri infection. These data could be valuable for breeding cultivars of P. bretschneideri with greater resistance to V. pyri.
Inflammatory responses induced by chronic cerebral hypoperfusion (CCH) play a critical role in the progression of vascular dementia. Stimulator of interferon genes (STING) signaling function as a key ...mediator of inflammation and immunological responses in the central nervous system (CNS), and resveratrol (RES) exerts potent anti-inflammatory effects. However, the role of STING signaling and the relationship between RES and STING signaling in persistent hypoperfusion-induced cerebral inflammation remain unclear. In this study, Sprague–Dawley rats were subjected to either Sham or bilateral common carotid artery occlusion (2VO) surgery and received RES or vehicle daily by intraperitoneal injection for 4 or 8 weeks. Morris’s water maze was used for the analysis of cognitive function. The neuroinflammatory responses in white matter and hippocampus of the rat brain were assessed by Western blot, Immunofluorescence staining, and qRT-PCR analyses. Myelin integrity, neutrophil infiltration, and microglia proliferation were assessed by Immunohistochemistry and histologic analysis. We demonstrated that after CCH, neurons, microglia, and astrocyte under endoplasmic reticulum (ER) stress upregulated the expression of STING, TANK-binding kinase 1 (TBK1), and the transcription factor interferon regulatory factor 3 (IRF3), as well as translocation of IRF3 into the nucleus. These were accompanied by infiltration of neutrophils, activation of microglia, and overproduction of proinflammatory mediators. Improvements in cognitive deficits were related to reduced hippocampal neuronal cell death and increased myelin integrity in RES-treated rats. The neuroprotective effects of RES were associated with suppression of the expression of tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecule 1 (ICAM-1), VCAM-1, interferon-β (IFN-β), and IL-1β, likely through mitigation of the STING/TBK1/IRF3 pathway. These inhibitory effects exerted by RES also inhibited the levels of myeloperoxidase, reduced excess expression of reactive astrocytes, and activated microglia. In conclusion, the STING/TBK1/IRF3 axis may be critical for proinflammatory responses in cerebral tissue with persistent hypoperfusion, and RES exerts its anti-inflammatory effects by suppressing STING/TBK1/IRF3 signaling.
Herbicidin F has an undecose tricyclic furano-pyrano-pyran structure with post-decorations. It was detected from Streptomyces mobaraensis US-43 fermentation broth as a trace component by HPLC-MS ...analysis. As herbicidins exhibit herbicidal, antibacterial, antifungal and antiparasitic activities, we are attracted to explore more analogues for further development.
The genome of S. mobaraensis US-43 was sequenced and a herbicidin biosynthetic gene cluster (hcd) was localized. The cluster contains structural genes, one transporter and three potential transcription regulatory genes. Overexpression of the three regulators respectively showed that only hcdR2 overexpression significantly improved the production of herbicidin F, and obviously increased the transcripts of 7 structural genes as well as the transporter gene. After performing homology searches using BLASTP in the GenBank database, 14 hcd-like clusters were found with a cluster-situated hcdR2 homologue. These HcdR2 orthologues showed overall structural similarity, especially in the C-terminal DNA binding domain. Based on bioinformatics analysis, a 21-bp consensus binding motif of HcdR2 was detected within 30 promoter regions in these genome-mined clusters. EMSA results verified that HcdR2 bound to the predicted consensus sequence. Additionally, we employed molecular networking to explore novel herbicidin analogues in hcdR2 overexpression strain. As a result, ten herbicidin analogues including six new compounds were identified based on MS/MS fragments. Herbicidin O was further purified and confirmed by
H NMR spectrum.
A herbicidin biosynthetic gene cluster (hcd) was identified in S. mobaraensis US-43. HcdR2, a member of LuxR family, was identified as the pathway-specific positive regulator, and the production of herbicidin F was dramatically increased by overexpression of hcdR2. Combined with molecular networking, ten herbicidin congeners including six novel herbicidin analogues were picked out from the secondary metabolites of hcdR2 overexpression strain. The orthologues of herbicidin F pathway-specific regulator HcdR2 were present in most of the genome-mined homologous biosynthetic gene clusters, which possessed at least one consensus binding motif with LuxR family characteristic. These results indicated that the combination of overexpression of hcdR2 orthologous regulator and molecular networking might be an effective way to exploit the "cryptic" herbicidin-related biosynthetic gene clusters for discovery of novel herbicidin analogues.
Air pollution has been standing as one of the most pressing global challenges. The changing patterns of air pollutants at different spatial and temporal scales have been substantially studied all ...over the world, which, however, were intricately disturbed by COVID-19 and subsequent containment measures. Understanding fine-scale changing patterns of air pollutants at different stages over the epidemic’s course is necessary for better identifying region-specific drivers of air pollution and preparing for environmental decision making during future epidemics. Taking China as an example, this study developed a multi-output LightGBM approach to estimate monthly concentrations of the six major air pollutants (i.e., PM2.5, PM10, NO2, SO2, O3, and CO) in China and revealed distinct spatiotemporal patterns for each pollutant over the epidemic’s course. The 5-year period of 2019–2023 was selected to observe changes in the concentrations of air pollutants from the pre-COVID-19 era to the lifting of all containment measures. The performance of our model, assessed by cross-validation R2, demonstrated high accuracy with values of 0.92 for PM2.5, 0.95 for PM10, 0.95 for O3, 0.90 for NO2, 0.79 for SO2, and 0.82 for CO. Notably, there was an improvement in the concentrations of particulate matter, particularly for PM2.5, although PM10 exhibited a rebound in northern regions. The concentrations of SO2 and CO consistently declined across the country over the epidemic’s course (p < 0.001 and p < 0.05, respectively), while O3 concentrations in southern regions experienced a notable increase. Concentrations of air pollutants in the Beijing–Tianjin–Hebei region were effectively controlled and mitigated. The findings of this study provide critical insights into changing trends of air quality during public health emergencies, help guide the development of targeted interventions, and inform policy making aimed at reducing disease burdens associated with air pollution.
PDF
