Junzhu Wu

Atherosclerosis (AS) is a chronic inflammatory disease caused by oxidative stress and the oxidation of low‑density lipoprotein (LDL). Xylitol, a widely used sugar substitute, has antioxidant potential; however, its effects on LDL‑induced oxidative stress in AS remain unclear. Using western blot, reverse transcription‑quantitative PCR, flow cytometry and so on, the present study investigated the role of xylitol in mitigating oxidative stress induced by high levels of LDL in Tohoku Hospital Pediatrics‑1 (THP‑1) human monocytic cell line), a model for studying AS. Xylitol significantly alleviated high LDL‑induced oxidative stress in THP‑1 cells and decreased reactive oxygen species levels, malondialdehyde content and the expression of NADPH oxidase family enzymes. Concurrently, xylitol enhanced the activity and expression of superoxide dismutase and increased the glutathione levels. Mechanistically, xylitol activated the nuclear factor erythroid 2‑related factor 2 (Nrf2)/heme oxygenase‑1 (HO‑1) axis by increasing the NADPH/NADP+ ratio via the regulation of the pentose phosphate pathway via the Nrf2 transcription factor. This led to a decrease in LDL oxidative modification in THP‑1 cells (Figs. 6,7). Overall, xylitol attenuates high LDL level‑induced oxidative stress in THP‑1 cells by modulating the Nrf2‑mediated pentose phosphate pathway and activating the Nrf2/HO‑1 axis, highlighting its potential for the prevention and treatment of AS.

Antimicrobial peptides (AMPs) are critical components of innate immunity in animals and plants, exhibiting thrilling prospectives as alternatives to traditional antibiotics due to their ability to combat pathogens without leading to resistance. Among these, Human Neutrophil Peptide-1 (HNP-1), primarily produced by human neutrophils, exhibits broad-spectrum antimicrobial activity against bacteria and viruses. However, the clinical application of HNP-1 has been hampered by challenges associated with mass production and inconsistent understanding of its bactericidal mechanisms. This review explores the structure and function of HNP-1, discussing its gene expression, distribution, immune functions and the regulatory elements controlling its production, alongside insights into its antimicrobial mechanisms and potential clinical applications as an antimicrobial agent. Furthermore, the review highlights the biosynthesis of HNP-1 using microbial systems as a cost-effective alternative to human extraction and recent studies revealing HNP-1’s endogenous bactericidal mechanism. A comprehensive understanding of HNP-1’s working mechanisms and production methods will pave the way for its effective clinical utilization in combating antibiotic-resistant infections.

Background Multiple sources such as university students' research and innovation projects, some of the teachers' research projects suitable for teaching practice, existing teaching experiments and literature, etc. Integrating the experimental results of morphology, functional and molecular biology and other disciplines into further experimental teaching mode can better integrate basic experimental skills with clinical development, meet the development needs of students and solve the problem of insufficient comprehensive basic teaching experiments, etc. It will further strengthen students' comprehensive application ability, overall thinking ability, practical hands-on ability, and analytical and adaptive ability. Methods A questionnaire on "Evaluation of existing basic medicine integrated experiments" was distributed to faculty members and undergraduate students in the School of Basic Medicine. Based on the results of the questionnaire, we propose to use multi-source projects as the original resources for the design of integrated experiments, design innovative integrated experiments covering multiple disciplines and meeting the needs of teaching and development of undergraduates by undergraduate volunteers in open laboratories, and evaluate the feasibility of the results of multi-source to the front line of experimental teaching through the evaluation form. Results Through feasibility assessment, the comprehensive experiments of basic medicine designed based on multi-source results have the characteristics of high comprehensiveness and feasibility, which can be transformed to the front line of experimental teaching. Conclusions Through this model, the aim is to achieve comprehensive integration of basic medical laboratory courses, to keep the laboratory courses abreast of cutting-edge achievements in the field, and to cultivate students' interest in and thinking about scientific research.

Human neutrophil peptide-1 (HNP-1) is a promising antibiotic candidate, but its clinical application has been hampered by the difficulty of mass production and an inadequate understanding of its bactericidal mechanisms. In this study, we demonstrated that recombinant protein expression combined with ultrafiltration may be a simple and cost-effective solution to HNP-1 production.

Proteomics approaches designed to catalogue all open reading frames (ORFs) under a defined set of growth conditions of an organism have flourished in recent years. However, no proteome has been sequenced completely so far. Here we generate the largest yeast proteome dataset, including 5610 identified proteins using a strategy based on optimized sample preparation and high-resolution mass spectrometry. Among the 5610 identified proteins, 94.1% are core proteins, which achieves near complete coverage of the yeast ORFs. Comprehensive analysis of missing proteins in our dataset indicate that the MS-based proteome coverage has reached the ceiling. A review of protein abundance shows that our proteome encompasses a uniquely broad dynamic range. Additionally, these values highly correlate with mRNA abundance, implying a high level of accuracy, sensitivity and precision. We present examples of how the data could be used, including re-annotating gene localization, providing expression evidence of pseudogenes. Our near complete yeast proteome dataset will be a useful and important resource for further systematic studies.

Ubiquitin ligases (E3s) serve as key regulators for the ubiquitylation-mediated pathway. The identification of the corresponding relationship between E3 and its substrates is challenging but required for understanding the regulatory network of ubiquitylation. The low abundance of ubiquitinated conjugates and high redundancy of E3 substrate regulation made the screening pretty hard. Herein, we combined SILAC-based quantitative proteomics with two contrary genetic methods (overexpression and knockout) in theory for E3 (Hrt3, the F-box subunit of the SCF complex) substrate screening. The knockout method could not overcome the constraint mentioned above, while the overexpression approach turned on the access to the potential substrates of E3. Subsequently, we obtained 77 candidates, which are involved in many critical biological processes and need to be verified in the future. Within these candidates, we confirmed the relationship between one of the candidates Nce103 and Hrt3 and linked Hrt3 with oxygen sensitivity and oxidative stress response in which Nce103 took part as well. This research is also beneficial for understanding the impact of oxygen supply on regulation of yeast growth through the ubiquitination of Nce103.

Chronic hepatitis B virus (HBV) infection is partly responsible for hepatitis, fatty liver disease and hepatocellular carcinoma (HCC). HBV core protein (HBc), encoded by the HBV genome, may play a significant role in HBV life cycle. However, the function of HBc in the occurrence and development of liver disease is still unclear. To investigate the underlying mechanisms, HBc-transfected HCC cells were characterized by multi-omics analyses. Combining proteomics and metabolomics analyses, our results showed that HBc promoted the expression of metabolic enzymes and the secretion of metabolites in HCC cells. In addition, glycolysis and amino acid metabolism were significantly up-regulated by HBc. Moreover, Max-like protein X (MLX) might be recruited and enriched by HBc in the nucleus to regulate glycolysis pathways. This study provides further insights into the function of HBc in the molecular pathogenesis of HBV-induced diseases and indicates that metabolic reprogramming appears to be a hallmark of HBc transfection.

Oxidized low‑density lipoprotein (LDL) has an important role in atherogenesis; however, the mechanisms underlying cell‑mediated LDL oxidation remain to be elucidated. The present study investigated whether native‑LDL induced lipid raft formation, in order to gain further insight into LDL oxidation. Confocal microscopic analysis revealed that lipid rafts were aggregated or clustered in the membrane, which were colocalized with myeloperoxidase (MPO) upon native LDL stimulation; however, in the presence of methyl‑β‑cyclodextrin (MβCD), LDL‑stimulated aggregation, translocation, and colocalization of lipid rafts components was abolished.. In addition, lipid raft disruptors MβCD and filipin decreased malondialdehyde expression levels. Density gradient centrifugation coupled to label‑free quantitative proteomic analysis identified 1,449 individual proteins, of which 203 were significantly upregulated following native‑LDL stimulation. Functional classification of the proteins identified in the lipid rafts revealed that the expression levels of translocation proteins were upregulated. In conclusion, the results of the present study indicated that native‑LDL induced lipid raft clustering in macrophages, and the expression levels of several proteins were altered in the stimulated macrophages, which provided novel insights into the mechanism underlying LDL oxidation.