KRAS, the most frequently mutated oncogene in human cancers, remains a challenging therapeutic target beyond the KRAS(G12C) mutant. Herein, two series of novel indole-based derivatives (19 compounds) were designed and synthesized as potential KRAS(G12D) inhibitors. Most compounds displayed potent antiproliferative effects against KRAS(G12D) mutant tumor cells (CT26 and A427), with IC50 values in the low micromolar range. Notably, compound 10d demonstrated significant inhibition of KRAS(G12D) mutant CT26 cell proliferation (IC50 = 2.04 mu M), along with substantial suppression of tumor cell migration (23.8% reduction in wound healing at 2.5 mu M) and colony formation (56.9% inhibition at 5 mu M), and induction of apoptosis (53.7% elevation at 5 mu M). Mechanistic studies revealed that compound 10d induced a 95.6% increase in intracellular ROS levels at 5 mu M while concurrently suppressing the PI3K/AKT/MAPK signaling pathway (>60% reduction in pAKT/pERK phosphorylation). In a KRAS(G12D)-driven CT26 allograft model, intraperitoneal administration of 10d (50 mg/kg) achieved significant tumor growth inhibition (20.1%) without observable toxicity. These findings collectively indicate that 10d is a promising KRAS(G12D) inhibitor worthy of further study and development as a potential anticancer therapy.

Although phosphatidylserine (PS) mixtures exhibit neuroprotective properties, the development of PS-based Alzheimer's disease (AD) therapeutics has been constrained by incomplete structure-activity relationship (SAR) data and poorly defined mechanisms. Herein, 34 novel PS derivatives were designed, synthesized, and evaluated for neuroprotective effects in vitro and in vivo. Most compounds exhibited excellent safety with IC50 values greater than 200 μM in normal cells and potent in vitro neurotrophic activity, exemplified by A18, which enhanced neuronal proliferation (increased by 29.4 ± 3.3%), rescued rotenone-injured neurons (cell survival increased by 42.5 ± 1.9%), and promoted synaptogenesis in primary neurons. Synaptogenesis was quantified by an increase of MAP2-positive neurite length (42.0 ± 2.3 μm in A18-treated neurons vs. 27.6 ± 2.9 μm in the control group, ∗∗p < 0.01), with further synergistic effects observed when combined with Neurotrophin Growth Factor (NGF). In Aβ1-42-induced AD mice, A18 (25 mg/kg/day) demonstrated multimodal efficacy: restoring spatial memory(as evidenced by an increase in platform crossings, ∗∗∗∗p < 0.0001), preserving synaptic ultrastructure, and reducing neuroinflammation (decreasing TNF-α/IL-6 levels by 40-60%, ∗p < 0.05). Mechanistic studies have revealed that A18 activates the PI3K/AKT and ERK-CREB signaling pathways while suppressing neuroinflammatory pathways. Critical SAR principles establish para-benzoates with nitro groups (e.g., A18) as optimal pharmacophores and glycerol backbone integrity as essential. These findings provide a foundation for future PS-based AD drug development.

Introduction Codonopsis Radix (CR), also known as Dangshen, is a renowned plant native to China, highly valued for its unique medicinal properties. However, due to the existence of numerous closely related origins and the similarities in their interspecies traits, microscopic characteristics, and physicochemical properties, different origins of CR have been circulating in the market, posing significant challenges for standardizing its medicinal use. Therefore, establishing an accurate identification method is crucial for advancing research on CR and ensuring its proper utilization.Methods In this study, a UHPLC-Q/TOF-MS analysis method was developed to identify differential metabolites among three origins of CR using one-way analysis of variance (ANOVA). The metabolites were distinguished based on the response ratios of the differential metabolites. Additionally, a neural network (NN) model was established to validate the classification capability.Results Metabolomic results revealed that among the 56 identified metabolites, 29 differential metabolites were screened out. Notably, the response ratios of codonopyrrolidium A, codonopyrrolidium D, tryptophan, and codonopsinol A against 3 '-hydroxy codonopyrrolidium B exhibited significant differences among the three origins. Verification experiments demonstrated that the NN model achieved a prediction accuracy of 100%, with a confidence measure exceeding 0.98.Discussion This study established two methods for identifying the origins of CR: a simple and rapid ratio method, and a highly accurate NN model. It demonstrated the feasibility of identifying the origins of CR through cross-validation, providing new insights and methodologies for the origin identification of multi-origin traditional Chinese medicine.

Patatin, a multifunctional glycoprotein from potatoes, is a promising lipase for industrial applications due to its emulsifying, antioxidant, and lipid-modifying properties. However, its low expression efficiency and preference for short-chain substrates limit practical utility. Here, we addressed these challenges by heterologously expressing patatin in Pichia pastoris X-33, achieving a yield of 121 mg/L through optimized fermentation. The enzyme showed optimal activity at 35 °C and pH 10.0, with methanol enhancing activity, while Fe2+/Fe3+ inhibited it. Rational design of the D286A mutant significantly improved long-chain substrate specificity (3.2-fold higher activity for pNP-C16) and thermal stability (ΔTm = +5.4 °C). Molecular dynamics revealed that the mutation disrupted an α-helix (residues 280-286), forming a flexible loop to accommodate long-chain substrates via hydrogen bonding and π-alkyl interactions. Structural integrity was confirmed by circular dichroism. This work provides a scalable platform for engineering patatin, with future studies targeting industrial-scale production and applications in functional lipids and biocatalysis.

Osteoporosis is a common systemic skeletal disease and a predominant underlying factor in the increased occurrence of fractures. The structure of isoflavones resembles that of estrogen and can confer similar but weaker effects. This study investigated the potential inhibitory effects of isoflavones from chickpea sprouts (ICS) on ovariectomy (OVX)-induced osteoporosis in vitro and in vivo. Notably, we found that ICS treatment could attenuate bone loss and improve trabecular microarchitecture and biomechanical properties of the fourth lumbar vertebra in OVX-induced osteoporotic rats and could also inhibit the development of a hyperosteometabolic state in this model. The osteogenic differentiation of bone marrow stem cells (BMSCs) was significantly enhanced by ICS intervention in vitro, and we confirmed that estrogen receptor α signaling was required for this increased osteogenic differentiation. Additionally, ICS has been shown to inhibit bone resorption via ERa modulation of the OPG/RANKL pathway. RANKL-induced osteoclastogenesis was reduced under ICS treatment, supporting that NF-κB signaling was inhibited by ICS. Thus, ICS attenuates osteoporosis progression by promoting osteogenic differentiation and inhibiting osteoclastic resorption. These results support the further exploration and development of ICS as a pharmacological agent for the treatment and prevention of osteoporosis.

Dead-End 1 (DND1) is an RNA-binding protein (RBP) with regulatory functions in multiple cancers, including gastric and colorectal. Nevertheless, the role that DND1 plays in prostatic cancer (PCa) as well as the hidden molecular mechanism is still obscure. The gene expression of DND1 and survival analyses in PCa were analyzed by the UALCAN database. Expression of DND1 and chloride intracellular channel 4 (CLIC4) were detected by qRT-PCR and western blot analysis. The Cell Counting Kit-8 assay and EDU staining were employed for the estimation of cell viability. The capabilities of cells to migrate and invade were appraised by the wound healing assay as well as the Transwell assay, while epithelial-mesenchymal transition (EMT) was measured by immunofluorescence and western blot assay. The interaction of DND1 and CLIC4 was predicted by PCTA, linkedomics, and RPISeq databases. It was discovered that DND1 expression was elevated in PCa cells. DND1 silencing had suppressive impacts on the proliferative, migrative, and invasive capabilities as well as EMT in DU145 and 22Rv1 cells. Mechanistically, bioinformatic analysis demonstrated that DND1 was negatively correlated with CLIC4 and that DND1 protein could bind to CLIC4 mRNA. Additionally, the CLIC4 level was reduced in PCa cells. CLIC4 depletion countervailed the suppressive impacts of DND1 deficiency on the capabilities of DU145 and 22Rv1 cells to proliferate, migrate, and invade as well as the process of EMT. These results suggested that DND1 silencing repressed the proliferation, migration, invasion, and EMT in PCa by regulating the mRNA level of CLIC4.

Neuronal regenerative ability is vital for the treatment of neurodegenerative diseases and neuronal injuries. Recent studies have revealed that Ganglioside GM3 and its derivatives may possess potential neuroprotective and neurite growth-promoting activities. Herein, six GM3 derivatives were synthesized and evaluated their potential neuroprotective effects and neurite outgrowth-promoting activities on a cellular model of Parkinson's disease and primary nerve cells. Amongst these derivatives, derivatives N-14 and 2C-12 demonstrated neuroprotective effects in the MPP + model in SH-SY5Y cells. 2C-12 combined with NGF (nerve growth factor) induced effecially neurite growth in primary nerve cells. Further action mechanism revealed that derivative 2C-12 exerts neuroprotective effects by regulating the Wnt signaling pathway, specifically involving the Wnt7b gene. Overall, this study establishes a foundation for further exploration and development of GM3 derivatives with neurotherapeutic potential.

BackgroundHistone modifications, especially the lysine acetylation, have drawn increasing attention in cancer research area. The aim of this research is to explore the molecular mechanisms underlying the regulation of lysine acetyltransferase 2 A (KAT2A) on colorectal cancer (CRC).MethodsClinical samples were collected from patients with CRC. The expression and correlation between KAT2A and ferroptosis suppressor SLC7A11 and glutathione peroxidase 4 (GPX4) were measured by qPCR and Pearson correlation analysis. NCP cells were transfected with KAT2A overexpression vectors or siRNAs. The proliferation of cells was measured by CCK-8 and colony formation assay. Cell migration and invasion was analyzed by Transwell. The accumulation of lipid peroxidation, ferrous iron, and malondialdehyde (MDA) were analyzed to determine cell ferroptosis. The expression of cell metastasis biomarkers was measured by western blotting assay. Interaction between KAT2A with GPX4 gene was measured by chromatin immunoprecipitation (ChIP).ResultsThe KAT2A, GPX4, and SLC7A11 expression was notably elevated in tumor tissues compared with the paired non-tumor tissues from CRC patients. The expression of KAT2A showed positive correlation with GPX4 and SLC7A11. Overexpression of KAT2A recovered the cell proliferation, migration, and invasion of CRC cells that suppressed by ferroptosis inducer erastin, along with deceased levels of ROS, iron, Fe2+, and MDA. Overexpression of KAT2A suppressed E-cadherin level and increased N-cadherin, Snail, and Vimentin expression in CRC cells. KAT2A interacted with GPX4 promoter region.ConclusionsIn conclusion, our findings demonstrated that KAT2A modulates the histone acetylation of GPX4 to regulate proliferation, metastasis, and ferroptosis of CRC cells.

BACKGROUND:Observational studies have shown an association between major depressive disorder (MDD), anxiety, and prostatitis. However, the causal relationship between MDD, anxiety, and prostatitis remains controversial. Therefore, we aimed to use two-sample Mendelian randomization (MR) to assess the causal effects of MDD and anxiety on prostatitis. METHODS:We conducted univariable and multivariable MR analyses using summary statistics from publicly available genome-wide association studies to estimate the causal relationships between MDD, anxiety, and prostatitis risk. In the main MR analysis, the inverse-variance weighted (IVW) method was used, while secondary methods included the weighted median, weighted mode, MR-Egger regression, and MR pleiotropy residual and outlier (MR-PRESSO) tests to detect and correct for the presence of pleiotropy. RESULTS:MDD had 97 independent instrumental variables (IVs) and anxiety had 15 IVs. Univariable MR analysis showed that genetically determined MDD had a detrimental causal effect on prostatitis (IVW: odds ratio [OR] = 1.47, 95% confidence interval [CI] = 1.12-1.92, p = 0.005), while no causal relationship was found between anxiety and prostatitis (IVW: OR = 0.25, 95% CI = 0.02-2.82, p = 0.26). More convincingly, after adjusting for confounding factors such as body mass index, alcohol consumption, and smoking, the genetic liability for MDD remained associated with prostatitis risk, with no strong evidence of anxiety affecting prostatitis incidence. CONCLUSION:This study supports the notion that MDD has a detrimental effect on prostatitis risk, and strategies focused on addressing MDD may be one of the cornerstones for treating prostatitis. The potential preventive value of treating MDD for prostatitis should be further investigated in future research.

The present study was conducted to investigate the distribution of pit organ in the critically endangered Chinese sturgeon (Acipenser sinensis), the similarities and differences in the microstructure of pit organ between Hybrid sturgeon and Chinese sturgeon, and to provide a histological basis for studying the pit organ in sturgeon species. We used hematoxylin-eosin (HE) staining, nissl staining, multi-layer fine scanning, and scanning electron microscopy to compare and analyse the microstructure of pit organ between Hybrid sturgeon and Chinese sturgeon. The results showed that the structure of pit organ of Hybrid sturgeon and Chinese sturgeon are similar. The distribution density of pit organ in different parts of Chinese sturgeon was different, and the density of pit organ on the ventral surface of the snout was the highest. Scanning electron microscopy revealed that the pit organ of Hybrid sturgeon and Chinese sturgeon were densely packed and about 500-1000 mu m wide. Nissl staining revealed that more peripheral nerves are distributed under the sensory and support cells of the pit organ. Based on previous research and our results, the increase in electrical receptivity of sturgeons with individual development is not only due to the increase in the number of inductive receptors, but may also be related to the increase in the width of the pit organ.

ABSTRACT l -Threonine aldolases (LTAs) are attractive biocatalysts for synthesizing β-hydroxy-α-amino acids (HAAs) via C–C bond formation in pharmaceuticals, although their industrial applications suffer from low activity and diastereoselectivity. Herein, we describe the discovery of a new LTA from Neptunomonas marine ( Nm LTA) that displays both ideal enzymatic activity (64.8 U/mg) and diastereoselectivity (89.5% diastereomeric excess; de) for the desired product l - threo -4-methylsulfonylphenylserine ( l - threo -MPTS). Using X-ray crystallography, site-directed mutagenesis, and computational modeling, we propose a “dual-conformation” mechanism for the diastereoselectivity control of Nm LTA, whereby the incoming 4-methylsulfonylbenzaldehyde (4-MTB) could potentially bind at the Nm LTA active site in two distinct orientations, potentially forming two diastereoisomers ( threo - or erythro -form products). Importantly, two key Nm LTA residues H140 and Y319 play critical roles in fine-tuning the binding mode of 4-MTB, supported by our site-mutagenesis assays. Uncovering of the catalytic mechanism in Nm LTA guides us to further improve the diastereoselectivity of this enzyme. A triple variant of Nm LTA (N18S/Q39R/Y319L; SRL) exhibited both improved diastereoselectivity (de value > 99%) and enzymatic activity (95.7 U/mg) for the synthesis of l - threo -MPTS compared with that of wild type. The preparative gram-scale synthesis for l - threo -MPTS with the SRL variant produced a space-time yield of up to 9.0 g L −1 h −1 , suggesting a potential role as a robust C–C bond synthetic tool for industrial synthesis of HAAs at a preparative scale. Finally, the SRL variant accepted a wider range of aromatic aldehyde derivatives as substrates and exhibited improved diastereoselectivity toward para -site substituents. This work provides deep structural insights into the molecular mechanism underlying the catalysis in Nm LTA and pinpoints the key structural motifs responsible for regulating the diastereoselectivity control, thereby guiding future attempts for protein engineering of various LTAs from different sources.

Esterases/lipases from the GDSL family have potential applications in the hydrolysis and synthesis of important esters of pharmaceutical, food, and biotechnical interests. However, the structural and functional understanding of GDSL enzymes is still limited. Here, we report the crystal structure of the GDSL family esterase EstL5 complexed with PMSF at 2.34 Å resolution. Intriguingly, the PMSF binding site is not located at the active site pocket but is situated in a surface cavity. At the active site, we note that there is a trapped crystallization solvent 1,6-hexanediol, which mimics the bound ester chain, allowing for further definition of the active site pocket of EstL5. The most striking structural feature of EstL5 is the presence of a unique channel, which extends approximately 18.9 Å, with a bottleneck radius of 6.8 Å, connecting the active-site pocket and the surface cavity. Replacement of Ser205 with the bulk aromatic residue Trp or Phe could partially block the channel at one end and perturb its access. Reduced enzymatic activity is found in the EstL5 S205W and EstL5 S205F mutants, suggesting the functional relevance of the channel to enzyme catalysis. Our study provides valuable information regarding the properties of the GDSL-family enzymes for designing more efficient and robust biocatalysts.

ObjectiveThe pathogenesis of peptic ulcer diseases (PUDs) involves multiple factors, and the contribution of gut microbiota to this process remains unclear. While previous studies have associated gut microbiota with peptic ulcers, the precise nature of the relationship, whether causal or influenced by biases, requires further elucidation.DesignThe largest meta-analysis of genome-wide association studies was conducted by the MiBioGen consortium, which provided the summary statistics of gut microbiota for implementation in the Mendelian randomization (MR) analysis. Summary statistics for five types of PUDs were compiled using the FinnGen Consortium R8 release data. Various statistical techniques, including inverse variance weighting (IVW), MR-Egger, weighted median (WM), weighted mode, and simple mode, were employed to assess the causal relationships between gut microbiota and these five PUDs.ResultIn the intestinal microbiome of 119 known genera, we found a total of 14 causal associations with various locations of PUDs and reported the potential pathogenic bacteria of Bilophila et al. Among them, four had causal relationships with esophageal ulcer, one with gastric ulcer, three with gastroduodenal ulcer, four with duodenal ulcer, and two with gastrojejunal ulcer.ConclusionIn this study, the pathogenic bacterial genera in the gut microbiota that promote the occurrence of PUDs were found to be causally related. There are multiple correlations between intestinal flora and PUDs, overlapping PUDs have overlapping associated genera. The variance in ulcer-related bacterial genera across different locations underscores the potential influence of anatomical locations and physiological functions.

The C-X-C chemokine receptor 4 (CXCR4) has been reported to be involved in several cancer related processes. The current study was designed to investigate the role of CXCR4 in human kidney cancer and to unveil the underlying molecular mechanisms. The results showed the expression of CXCR4 to be significantly (P<0.05) upregulated in human renal cancer tissues and cell lines. Silencing of CXCR4 lead to a significant (P<0.05) decline of cell proliferation and colony formation of the Caki-1 and A498 kidney cancer cells. Moreover, the migration and invasion of the Caki-1 and A498 cells was also significantly (P<0.05) inhibited upon CXCR4 silencing. TargetScan analysis and dual luciferase assay revealed that CXCR4 interacts with microRNA-139 (miR-139). The expression of miR-139 was found to be significantly (P<0.05) downregulated in human kidney cancer cells lines. Overexpression of miR-139 caused post-transcriptional suppression of CXCR4 expression and significant (P<0.05) inhibition of the Caki-1 and A498 cell proliferation. Nonetheless, CXCR4 overexpression could nullify the inhibitory effects of miR-139 on the proliferation of Caki-1 and A498 cells. Taken together, the results revealed that CXCR/miR-139 axis regulates the proliferation, migration, and invasion of human kidney cancer cells and may act as a therapeutic target.

Cancer is a leading cause of death worldwide. Recent research studies have revealed that GM3 derivatives have considerable promise as potential therapeutic agents for cancer. To discover novel GM3 derivatives as potential antitumor agents, a one-pot enzymatic synthesis was established, yielding 14 GM3 derivatives in high total yields (22-41%). Subsequently, the inhibitory activities of GM3 derivatives were assessed by wound-healing assays and Transwell assays and tumor-bearing animal models. Among all the GM3 derivatives, N-12 showed excellent migration and invasion inhibitory effects in cells and marked antitumor activity in C57BL/6 mice. The subsequent analysis of cancer tissues and serum samples revealed that N-12 induces tumor inhibition, which was closely related to immune response. Taken together, N-12 can be further developed as an effective therapeutic for the treatment of cancer. An RNA-sequencing (RNA-seq) analysis was then performed and indicated that the antitumor mechanism of N-12 involved focal adhesion and ECM-receptor interaction signaling pathways.

文章以新冠肺炎疫情防控期间,上海交通大学医学院附属新华医院普外科2022届研究生毕业论文线上"云答辩"为例,阐述了医学院校线上"云答辩"的组织流程,并总结经验,论述"云答辩"优势,即符合疫情管控要求、节约答辩成本、答辩参与度广,最后提出了更好开展"云答辩"的几点建议,包括统一组织答辩秘书培训、规范答辩流程、加强检查督导,以期推动医学院校研究生毕业论文答辩形式的改革和创新.

目的 研究菊科蜂斗菜属植物毛裂蜂斗菜Petasites tricholobus全草中倍半萜类化学成分.方法 采用正相硅胶、反相硅胶、葡聚糖凝胶、微孔树脂等多种柱色谱填料进行分离纯化,并运用MS、NMR、UV、IR等现代波谱分析技术对化合物结构进行鉴定.结果 从毛裂蜂斗菜50％乙醇提取物中分离得到5个倍半萜类化合物,分别鉴定为1α-(cis-methylthioacryloyloxy)-8α-angeloyloxy-3β,4β-epoxy-bisabola-7(14),10-diene(1)、bakkenolide Ⅲb(2)、monoketone(3)、japonipene C(4)和petatewalideA(5).结论 化合物1为新化合物,命名为毛裂蜂斗菜素;化合物2～5均为首次从毛裂蜂斗菜中分离得到.

Underwater noise from ship engines can affect the metabolism and immune system of various fish species. Meanwhile, changes in the metabolic pathways in liver are important for fish to adapt to adverse environments. We used a combined multi-omics analysis to investigate the response mechanism of hybrid sturgeon to continuously played ship noise. A control group and a noise group (simulated ship noise: 12 h) were set up, and liver tissues were extracted for high-throughput transcriptome and metabolome sequencing. The results show that a total of 588 differentially expressed genes (DEGs) and 58 DEGs metabolites were detected. The joint analysis of transcriptome and metabolome showed that under noise stress, apoptosis and cell motility were intensified, DNA replication, RNA transcription and translation, and protein synthesis were inhibited, and lipid metabolism, nucleotide metabolism, and vitamin D3 metabolic pathways were also inhibited. Interestingly, the initiation of a partial immune responses ensured their normal immunity abilities. Moreover, material and energy requirements of the organism under noise stress were guaranteed by upregulation of carbohydrate and amino acid metabolic pathways.

Stem cells represent a unique population of cells with self-renewal capacity. However, the molecular control of self-renewal and differentiation of stem cells has remained enigmatic. Here, we show that short-type PB-cadherin (STPB-C) promoted self-renewal of spermatogonial stem cells (SSCs) via activating Janus kinase/signal transducer and activator of transcription (JAK-STAT) and phosphoinositide-3 kinase (PI3-K)/Akt, and blocking transforming growth factor (TGF)-β1 signaling. These data were obtained with varied approaches, including the use of RNA interference (RNAi), SSC cultures infected by STPB-C retroviral vector, bromodeoxyuridine (BrdU) incorporation assay, and other techniques. These findings have important implications for germ cell biology and create the possibility of using SSCs for biotechnology and medicine. They are also critical in understanding tissue homeostasis, the aging process, tumor formation and degenerative diseases.

Sortase A (SrtA) is a cysteine transpeptidase of most gram-positive bacteria that is responsible for the anchoring of many surface protein virulence factors to the cell wall. SrtA ablation has demonstrated to alleviate the infection without affecting the viability of bacteria. Herein, a series of benzofuran cyanide derivatives were synthesized and evaluated. Several compounds exhibited excellent inhibitory activity against SrtA with IC50 values from 3.3 μM to 21.8 μM compared with the known SrtA inhibitor pHMB (IC50 = 130 μM). Ⅲ-1, Ⅲ-15, Ⅲ-34 and V-1 showed potent inhibitory effects on biofilm formation with IC50 values from 2.1 μM to 54.2 μM. Invasion assays showed the four compounds caused a decrease of 4%-24.0% in the uptake of the S. aureus strain by 293T cells. Further assay showed that compound Ⅲ-15 decreased the amount of cell wall-associated protein A by 26.5%. Structure-activity relationship and docking studies demonstrated that the acrylonitrile moiety of the compounds played an important role in enhancing the activity. When the double bond of acrylonitrile changed to single bond, the activity was decreased significantly. This indicates that acrylonitrile, which is a Michael receptor, can inhibit the activity of SrtA by covalent binding effectively to the thiol group of Cys184.