Journal of Zhejiang University SCIENCE B最新文献

Vegetables are important dietary sources of folate for human nutrition. The influence of different nitrogen doses and forms on changes in primary nitrogen metabolism, such as amino acid and protein synthesis, in plants is well established. However, the impacts of the nitrate-N (N O 3-)-to-ammonium-N (N H 4+) ratio on folate synthesis and accumulation in vegetables are unclear. This study used a hydroponic experiment with six different N O 3-/ N H 4+ ratio treatments to investigate the effects of the integrated application of N O 3- and N H 4+ on the folate constituents and contents of pakchoi (Brassica rapa subsp. chinensis). The results indicated that an appropriate N O 3-/ N H 4+ ratio in nutrient solution could promote pakchoi growth and increase folate contents by increasing polyglutamylated 5-formyl-tetrahydrofolate (5-CHO-THF) and polyglutamylated 5-methyl-THF (5-CH₃-THF). The activities of enzymes related to folate biosynthesis (except folylpolyglutamate synthase (FPGS)) were lower with an N H 4+-N supply at the same nitrogen concentration. The statistical results revealed a significant negative correlation between folate contents and 14 detected metabolites (including fructose, sucrose, glutamine (Gln), shikimate, citrate, succinate, malate, α-oxoglutarate, p-aminobenzoate (pABA), and 6-hydroxymethyldihydropterin pyrophosphate (HMDH-P₂) in the folate biosynthesis pathway), implying that the enhancement of folates biosynthesis with N H 4+-N supply increased the consumption of the folate precursors and intermediate metabolites. Additionally, N H 4+-N supply could improve folate stability by increasing polyglutamylated folates and reducing γ-glutamyl hydrolase (GGH) activity; the latter could weaken folate deglutamylation. As the best growth and highest total folate content were obtained at the appropriate N O 3-/ N H 4+ ratio, strategic selection of the N O 3-/ N H 4+ ratio should be considered for the hydroponic cultivation of foliar vegetable crops.

Neurokinin-1 receptor (NK1R), a member of the G protein-coupled receptor (GPCR) family, contributes to multiple pathological processes, including pain, chronic inflammation, and cancer (Gutierrez et al., 2019; Robinson et al., 2023). Current reports and our previous work have proven that NK1R is highly expressed in many cancer cells, such as colorectal cancer and leukemia, and that targeted blocking of NK1R can effectively inhibit tumor cell proliferation (Li XQ et al., 2013; Li JY et al., 2016; Ge et al., 2019; Shi et al., 2021). In addition, GPCRs have been found not only in the plasma membrane but also in the membranes of endosomes and lysosomes with endocytosis (Irannejad et al., 2017; Yarwood et al., 2017), which is more pronounced in cancer cells with highly developed lysosomes (Ramírez-García et al., 2019).

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors worldwide. This necessitates the development of innovative drugs with high efficiency, low toxicity, and good tolerance. Bitter melon extract has been reported to have potent anticancer activity against OSCC. We evaluated the effects of nine triterpenoids from bitter melon extract on OSCC using cell counting kit-8 (CCK-8) proliferation and Transwell migration assays. Among the nine triterpenoids, momordicine I (MI) exhibited the strongest anticancer activity against OSCC. Animal experiments also showed that MI inhibited OSCC cell growth in vivo. Additionally, MI decreased the mitochondrial membrane potential and promoted apoptosis in OSCC. RNA-sequencing (RNA-seq) analysis revealed that MI induced an unfolded protein response (UPR) and endoplasmic reticulum (ER) stress, which was confirmed by western blotting and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cellular thermal shift assay (CETSA) and mass spectrometry (MS) analysis, combined with molecular docking, identified ribosomal proteins (ribosomal protein L7 (RPL7), RPL11, RPL12, RPL18, RPL30, RPL38, RPS13, and RPS25) as MI targets. By targeting ribosomal proteins, MI likely disrupts ribosome-mediated protein folding, leading to the UPR and ER stress. In summary, MI targets ribosomal proteins to induce ER stress and inhibit OSCC, highlighting its therapeutic potential.

This study used molecular dynamics simulations, B-factor analysis, and saturation mutagenesis screening to enhance the thermal stability of the trans-epoxysuccinate hydrolase (TESH) derived from Pseudomonas koreensis. Eleven mutants that influence this characteristic were selected, yielding four mutants with improved activity. Among them, mutants A142C and S178Q exhibited lower Michaelis constant (K_m) values, and their k_cat/K_m ratios (k_cat, catalytic constant) were 3.7 and 0.9 times higher than those of the wild type, respectively. The values of half-life at 50 ℃ (T 1/ 2 50) of the two mutants were increased by 107% and 59%, respectively, compared to the wild type. Molecular docking and molecular dynamics simulations indicated that the two mutants showed stronger substrate interaction, lower binding energy, and reduced root mean square deviation compared to the wild type, along with decreased electrostatic potential energy and increased hydrophobicity near their mutation sites. The study of protein thermal stability engineering and associated mechanisms provides a valuable reference and holds practical significance for the industrial production of meso-tartaric acid.

The intestinal microbiome, which is a key factor in the maintenance of host gut homeostasis, enhances intestinal mucosal barrier function and immune tolerance (Rooks and Garrett, 2016; Skelly et al., 2019). However, the specific immunomodulatory functions of microbiota-derived metabolites in mucosal inflammatory responses remain largely unknown. The effects of microbial metabolites may vary across different immune cell types and host homeostasis (Hu et al., 2023; Zhao et al., 2023). Hence, it is fundamental to understand how specific intestinal microbes and their metabolic small molecules cause or mitigate gut-related diseases like inflammatory bowel disease (IBD). It has been uncovered that during the pathogenesis of IBD, excessive T helper 1 cell (Th1)/Th17 activation and impaired function of colonic regulatory T cells (Tregs) occur (Subramanian, 2020). Given that colonic Tregs play an important role in inhibiting IBD via secreting immunosuppressive cytokines, the molecular mechanisms linking certain intestinal microbes and their metabolites to Treg-mediated immune tolerance are yet to be fully understood.

Digestive enzymes of fish are critical to food digestion at the larval stage, but convincing evidence proving the function and necessity of the associated digestive enzymes remains lacking. In this study, we generated the trypsin (try) gene and amylase (amy) gene in the Japanese medaka (Oryzias latipes) using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) for the first time. try deletion significantly decreased the expression of try anddigestive capacity in try^-/- medaka larvae; after 8.5 h of digestion, incompletely digested brine shrimp was observed in the digestive tract at 4 and 15 d post-hatching (dph) of try^-/- medaka larvae. Furthermore, the height of intestinal villi and total body length decreased significantly within 15-dph try^-/- medaka larvae. However, amy deletion did not influence the digestion of medaka larvae at 4 dph. Only a small amount of incompletely digested brine shrimp was observed in 15-dph amy^-/- medaka larvae. Further analysis of the growth, nitrogen metabolism, and intestinal microbes of try^-/- adult medaka showed that the body length and weight of adult medaka decreased significantly, while the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the blood significantly increased. Pathological observation of the liver and intestinal tissues showed that try knockout resulted in vacuolar degeneration of liver cells, thinning of the intestinal wall, sparse arrangement of villi, and lower villi height. High-throughput 16S ribosomal RNA (rRNA) sequencing revealed that try knockout reduced the diversity of intestinal microbes. These findings demonstrated that try was indispensable for medaka larvae because it continuously affects their growth, nitrogen metabolism, and intestinal development.

Real-world studies (RWSs) have emerged as a transformative force in oncology research, complementing traditional randomized controlled trials (RCTs) by providing comprehensive insights into cancer care within routine clinical settings. This review examines the evolving landscape of RWSs in oncology, focusing on their implementation, methodological considerations, and impact on precision medicine. We systematically analyze how RWSs leverage diverse data sources, including electronic health records (EHRs), insurance claims, and patient registries, to generate evidence that bridges the gap between controlled clinical trials and real-world clinical practice. The review underscores the key contributions of RWSs, including capturing therapeutic outcomes in traditionally underrepresented populations, expanding drug indications, and evaluating long-term safety and effectiveness in routine clinical settings. While acknowledging significant challenges, including data quality variability and privacy concerns, we discuss how emerging technologies like artificial intelligence are helping to address these limitations. The integration of RWSs with traditional clinical research is revolutionizing the paradigm of precision oncology and enabling more personalized treatment approaches based on real-world evidence.

Dietary consumption of eicosapentaenoic acid (EPA) offers diverse health benefits, such as the regulation of blood triglycerides and the prevention of cardiovascular diseases. EPA is naturally synthesized by Schizochytrium sp.; however, its low production level limits its potential for industrial application. The goal of this study was to increase EPA productivity in Schizochytrium sp. by gas‒liquid-phase plasma (GLPP) mutagenesis combined with a high-throughput screening method. First, a diverse array of mutants was generated through GLPP mutagenesis. Next, the mutants with elevated EPA productivity were identified through near-infrared spectroscopy (NIRS). Notably, the M7-25 mutant demonstrated the highest and most consistent EPA production. After the culture medium was optimized, the EPA titer increased from 0.45 to 1.70 g/L. Finally, a cofermentation strategy using ammonia and glucose feeding was employed, and the EPA titer reached 2.08 g/L in a 7-L fermenter. This study reports the highest EPA titer achieved in Schizochytrium sp. via mutagenesis to date, highlighting its great market potential for industrial production.

Premenstrual dysphoric disorder (PMDD), a subtype of premenstrual syndrome (PMS), involves physical and emotional symptoms that impact patients' daily lives and productivity. A reliable, side-effect-free clinical intervention is needed. Shuyu capsule is an effective traditional Chinese medicine preparation for PMDD used in the clinics, but its therapeutic mechanism remains unclear. Previous research has suggested that the γ-aminobutyric acidergic (GABAergic) system in the periaqueductal gray (PAG) may play a role in treating PMDD with traditional Chinese medicine, but there is a lack of functional verification. This study aims to reveal the potential mechanism of the Shuyu capsule in treating PMDD. The study employed an experimental design using female C57BL/6J and Vgat-Cre mice to assess the effects of Shuyu capsules on PMDD, with a focus on the GABAergic system in the dorsal PAG (dPAG). Assessments were conducted using the forced swimming test (FST) to gauge depression-like behaviors and western blot (WB) and immunofluorescence (IF) to measure the numbers of active GABAergic neurons and the γ-aminobutyric acid type A receptor (GABA_AR) δ subunit (GABRD) expression. Chemogenetic techniques and adeno-associated virus were specifically used to activate GABAergic neurons and knock down the expression of subunits, respectively, providing insights into the neurobiological mechanisms underpinning the therapeutic effects of Shuyu capsules in treating PMDD. After being stressed by FST, the immobility duration of PMDD mice in the late dioestrus (LD) phase decreased after the Shuyu capsule intervention, implying that it can improve the estrous cycle-dependent depression-like phenotype in PMDD mice. Additionally, the application of Shuyu capsule can downregulate the expression of GABRD and reverse the downtrend of activated GABAergic neurons in the dPAG of PMDD model mice. We also found that single-target manipulation was enough to improve the depression-like behavior of PMDD model mice. Transgenic mice with GABRD knockout were established, and their behaviors were tested, revealing changes in their exploratory behaviors, indicating that the GABRD may be closely related to anxiety disorders. Shuyu capsule plays an anti-PMDD role by activating GABAergic neurons and downregulating the expression of GABRD in the dPAG. This provides a theoretical basis for the clinical treatment of PMDD with traditional Chinese medicine and promotes the development of drugs for treating PMDD.

Carbonyl reductase 1 (CBR1), a member of the short-chain dehydrogenase/reductase (SDR) superfamily, is implicated in tumor progression and treatment resistance. However, its role in non-small cell lung cancer (NSCLC) remains unclear. This study examined CBR1 expression in NSCLC tissues and cell lines, using gene interference and pharmacological inhibition to assess its impact on stemness, chemosensitivity, and quiescence, and to explore underlying mechanisms. Our findings indicate that CBR1 expression is elevated in NSCLC tissues and cell lines, and further increases in the presence of cisplatin (CDDP). Gene interference reducing CBR1 expression significantly decreased the percentage of cluster of differentiation 133 (CD133)-positive cells and the expression of octamer-binding transcription factor 4 (OCT4) and SRY (sex determining region Y)-box 2 (SOX2), while enhancing CDDP chemosensitivity. The CBR1-specific inhibitor hydroxy-PP-Me (PP-Me) markedly increased CDDP cytotoxicity and reduced stemness. Additionally, CBR1 inhibition via short hairpin RNA (shRNA) CBR1 (sh-CBR1) or PP-Me disrupted NSCLC cell quiescence, as shown by a decrease in G0 phase cells and p27 expression, alongside an increase in cyclin D1 and phospho-retinoblastoma (pRb) expression. Furthermore, SET domain-containing protein 4 (SETD4), which mediates stemness, chemosensitivity, and quiescence in NSCLC cells, was downregulated by sh-CBR1 or PP-Me treatment. The overexpression of SETD4 counteracted the enhanced chemosensitivity resulting from CBR1 inhibition. In A549 xenografts, combined PP-Me and CDDP therapy significantly inhibited tumor growth compared to either treatment alone. In conclusion, CBR1 inhibition enhances CDDP chemosensitivity by suppressing stemness and quiescence in NSCLC.