Unmasking Spatial Heterogeneity in Phytotoxicology Mechanisms Induced by Carbamazepine by Mass Spectrometry Imaging and Multiomics Analyses.

Previous studies have highlighted the toxicity of pharmaceuticals and personal care products (PPCPs) in plants, yet understanding their spatial distribution within plant tissues and specific toxic effects remains limited. This study investigates the spatial-specific toxic effects of carbamazepine (CBZ), a prevalent PPCP, in plants. Utilizing desorption electrospray ionization mass spectrometry imaging (DESI-MSI), CBZ and its transformation products were observed predominantly at the leaf edges, with 2.3-fold higher concentrations than inner regions, which was confirmed by LC-MS. Transcriptomic and metabolic analyses revealed significant differences in gene expression and metabolite levels between the inner and outer leaf regions, emphasizing the spatial location's role in CBZ response. Notably, photosynthesis-related genes were markedly downregulated, and photosynthetic efficiency was reduced at leaf edges. Additionally, elevated oxidative stress at leaf edges was indicated by higher antioxidant enzyme activity, cell membrane impairment, and increased free fatty acids. Given the increased oxidative stress at the leaf margins, the study suggests using in situ Raman spectroscopy for early detection of CBZ-induced damage by monitoring reactive oxygen species levels. These findings provide crucial insights into the spatial toxicological mechanisms of CBZ in plants, forming a basis for future spatial toxicology research of PPCPs.

Effects of a manganese complex with lysine and glutamic acid on growth performance, manganese deposition, and emission, antioxidant capacity and metacarpal strength in weaned piglets.

The present study sought to assess the effects of manganese complexes with lysine and glutamic acid (Mn-LG) as manganese (Mn) sources on growth performance, trace element deposition, antioxidant capacity, and metacarpal strength in weaned piglets. The study involved 288 healthy Duroc × Landrace × Yorkshire piglets that were weaned at 25 to 28 d of age and weighed 8.66 ±â€…0.96 kg. These piglets were randomly divided into six groups: a control group (Mn-LG-0, receiving a basal diet without Mn supplementation), a Mn sulfate group (basal diet supplemented with 40 mg·kg-1 diet of Mn, Mn-S-40 group), and four Mn-LG groups (Mn-LG-20, Mn-LG-40, Mn-LG-60, Mn-LG-80, supplemented with 20, 40, 60, and 80 mg·kg-1 Mn from Mn-LG in the basal diet). Grouping began at weaning on the 0th day of the experiment. The corn-soybean-based basal diet during the early (days 0 to 14) and late (days 15 to 42) phases of the experiment contained 20.88 and 30.12 mg·kg-1 Mn, respectively. Blood samples were collected on days 14 and 42, and pigs were sacrificed for sample collection on day 42. The results indicated no significant differences in average daily gain, average daily feed intake, or feed-to-gain ratio among the groups (P > 0.05). The diarrhea rates of all Mn-LG groups and the Mn-S-40 group were significantly lower in the 0 to 14 d and during the entire experimental period than in the Mn-LG-0 group (P < 0.001). The Mn-LG-40 group exhibited a significant increase in liver Mn concentration and serum Mn superoxide dismutase (Mn-SOD) activity on day 42 (P < 0.01), as well as a significant decrease in fecal Mn concentration (P < 0.05), compared to those of the Mn-S-40 group. Significant differences (P < 0.05) were detected in the serum, liver, and fecal Mn concentrations, as well as in the serum and liver Mn-SOD activity, across the different Mn-LG groups. The serum and fecal Mn concentrations and serum Mn-SOD activity increased linearly or quadratically (P < 0.01) with increasing Mn-LG supplementation. No significant differences (P > 0.05) were found in kidney, heart, or metacarpal bone Mn concentrations or in bone strength indices. In summary, compared with the Mn-LG-0 diet, dietary supplementation with Mn-LG enhanced serum Mn deposition and Mn-SOD activity and decreased the incidence of diarrhea. Additionally, the fecal Mn concentration was lower in the Mn-LG group than in the inorganic group at equivalent dosages.

This research explored the effects of a manganese complex containing lysine and glutamic acid (Mn-LG) on various health parameters in weaned piglets. Utilizing samples of 288 piglets, the study investigated how Mn-LG supplementation influences growth performance, Mn deposition and emission, antioxidant capacity, and metacarpal strength. Key findings include an increase in serum Mn levels and Mn superoxide dismutase (Mn-SOD) activity, a reduction in diarrhea incidence, and no significant effects in bone strength indices in piglets receiving Mn-LG. Additionally, the fecal Mn concentration was notably lower in the Mn-LG group than in the group receiving inorganic Mn at equivalent dosages.

Imaging and quantification of neuropeptides in mouse pituitary tissue by atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry.

RATIONALE: Atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) mass spectrometry has enabled the untargeted analysis and imaging of neuropeptides and proteins in biological tissues under ambient conditions. Sensitivity in AP-MALDI can be improved by using sample-specific preparation methods. METHODS: A comprehensive and detailed optimization strategy including instrument parameters, matrix spraying and sample tissue washing pretreatment was implemented to enhance the sensitivity and coverage of neuropeptides in mouse pituitary tissues by commercial AP-MALDI mass spectrometry imaging (MSI). RESULTS: The sensitivity of a commercial AP-MALDI system for endogenous neuropeptides in mouse pituitary was enhanced by up to 15.2-fold by shortening the transmission gap from the sample plate to the inlet, attaching copper adhesive tape to an indium tin oxide-coated glass slide, optimizing the matrix spray solvent and using sample tissue washing pretreatment. Following careful optimization, the distributions of nine endogenous neuropeptides were successfully visualized in the pituitary. Furthermore, the quantitative capability of AP-MALDI for neuropeptides was evaluated and the concentrations of neuropeptides oxytocin and vasopressin in the pituitary posterior lobe were increased approximately twofold under hypertonic saline stress. CONCLUSION: Mouse pituitary neuropeptides have emerged as important signaling molecules due to their role in stress response. This work indicates the potential of modified AP-MALDI as a promising AP MSI method for in situ visualization and quantification of neuropeptides in complex biological tissues.

Development of Transmission Ambient Pressure Laser Desorption Ionization/Postphotoionization Mass Spectrometry Imaging.

Laser-based high-resolution mass spectrometry imaging at ambient conditions has promising applications in life science. However, the ion yield during laser desorption/ablation is poor. Here, transmission atmospheric pressure laser desorption ionization combined with a compact postphotoionization (t-AP-LDI/PI) assembly with a krypton discharge lamp was developed for the untargeted imaging of various biomolecules. The spatial distributions of numerous lipid classes, fatty acids, neurotransmitters, and amino acids in the subregions of mouse cerebellum tissue were obtained. Compared with single laser ablation, the sensitivities for most analytes were increased by 1 to 3 orders of magnitude by dopant-assisted postphotoionization. After careful optimization, a spatial resolution of 4 µm could be achieved for the metabolites in mouse hippocampus tissue. Finally, the melanoma tissue slices were analyzed using t-AP-LDI/PI MSI, which revealed the metabolic heterogeneity of the melanoma microenvironment and exhibited the phenomenon of abnormal proliferation and invasion trends in tumor cells.

Construction of a co-expression network affecting intramuscular fat content and meat color redness based on transcriptome analysis.

Introduction: Intramuscular fat content (IFC) and meat color are vital indicators of pork quality. Methods: A significant positive correlation between IFC and redness of meat color (CIE a* value) indicates that these two traits are likely to be regulated by shared molecular pathways.To identify candidate genes, hub genes, and signaling pathways that regulate these two traits, we measured the IFC and CIE a* value in 147 hybrid pigs, and selected individuls with extreme phenotypes for transcriptome analysis. Results: The results revealed 485 and 394 overlapping differentially expressed genes (DEGs), using the DESeq2, limma, and edgeR packages, affecting the IFC and CIE a* value, respectively. Weighted gene co-expression network analysis (WGCNA) identified four modules significantly correlated with the IFC and CIE a* value. Moreover, we integrated functional enrichment analysis results based on DEGs, GSEA, and WGCNA conditions to identify candidate genes, and identified 47 and 53 candidate genes affecting the IFC and CIE a* value, respectively. The protein protein interaction (PPI) network analysis of candidate genes showed that 5 and 13 hub genes affect the IFC and CIE a* value, respectively. These genes mainly participate in various pathways related to lipid metabolism and redox reactions. Notably, four crucial hub genes (MYC, SOX9, CEBPB, and PPAGRC1A) were shared for these two traits. Discussion and conclusion: After functional annotation of these four hub genes, we hypothesized that the SOX9/CEBPB/PPARGC1A axis could co-regulate lipid metabolism and the myoglobin redox response. Further research on these hub genes, especially the SOX9/CEBPB/PPARGC1A axis, will help to understand the molecular mechanism of the co-regulation of the IFC and CIE a* value, which will provide a theoretical basis for improving pork quality.