Synergistic effects of Ω-3 polyunsaturated fatty acid supplementation and programmed cell death protein 1 blockade on tumor growth and immune modulation in a xenograft model of esophageal cancer.

BACKGROUND: Esophageal cancer, especially esophageal squamous cell carcinoma (ESCC), remains a significant global health challenge with limited survival rates. This study aimed to elucidate the combined effects of immune-modulating nutrition (IMN) with Ω-3 polyunsaturated fatty acid (PUFA) supplementation and anti-programmed cell death protein 1 (PD-1) treatment on tumor growth and immune responses in a xenograft model of ESCC. METHODS: A total of 36 C57BL/6 mice were used to construct a xenograft model using the mouse esophageal cancer cell line AKR. Mice were subjected to treatment with anti- PD-1 antibody combined with either Ω-3 PUFA-rich or Ω-3 PUFA-deficient nutrition. Tumor growth, immune markers, cytokine profiles, and metabolic changes were evaluated. RESULTS: The combination of anti-PD-1 and Ω-3 PUFA supplementation significantly inhibited tumor growth more effectively than anti-PD-1 treatment alone. Enhanced expression of immune markers PD-L1 and CD3 was observed in Ω-3 PUFA-fed mice. Additionally, compared with anti-PD-1 therapy and anti-PD-1 plus Ω-3 PUFA-deficient nutrition, Ω-3 PUFAs intensified alterations in key chemokines and cytokines, including elevated IL-12, IFN-γ, and GM-CSF levels, and reduced CXCL12 levels. However, Ω-3 PUFAs did not significantly alter the glycolysis and tryptophan metabolic program induced by anti-PD-1. CONCLUSION: Our findings indicated the potential synergetic therapeutic benefits of combining anti-PD-1 treatment with Ω-3 PUFA supplementation in ESCC, which offered promising avenue for further research.

Polymethoxylated flavones from the leaves of Vitex negundo have fungal-promoting and antibacterial activities during the production of broad bean koji.

Broad bean paste is a popular condiment in Asian countries. Leaves of Vitex negundo Linn. were used extensively in China during the koji-making of broad bean paste. Spreading V. negundo leaves on raw broad beans during fermentation was able to facilitate the rapid growth of fungi to form mature koji. We isolated two strains of fungi from mature koji, and four strains of bacteria from the rotten broad beans resulting from a failed attempt. According to microbial activity assays, two polymethoxylated flavones, 5-hydroxy-3,6,7,8,3',4'-hexamethoxy flavone (HJ-1) and 5,4'-dihydroxy-3,6,7,8,3'-pentamethoxy flavone (HJ-2) were isolated from V. negundo leaves, and the fungal growth promotion and inhibition of bacterial growth of these two compounds were found to improve the production of broad bean koji. This study reveals the compounds present in V. negundo leaves with bioactivity against important microbes in koji manufacture, and provides a theoretical basis for the application of V. negundo in broad bean paste production.

Oral microbiota dysbiosis alters chronic restraint stress-induced depression-like behaviors by modulating host metabolism.

Studies have shown that the microbiota-gut-brain axis is highly correlated with the pathogenesis of depression in humans. However, whether independent oral microbiome that do not depend on gut microbes could affect the progression of depression in human beings remains unclear, neither does the presence and underlying mechanisms of the microbiota-oral-brain axis in the development of the condition. Hence this study that encompasses clinical and animal experiments aims at investigating the correlation between oral microbiota and the onset of depression via mediating the microbiota-oral-brain axis. We compared the oral microbial compositions and metabolomes of 87 patients with depressive symptoms versus 70 healthy controls. We found that the oral microbial and metabolic signatures were significantly different between the two groups. Significantly, germ-free (GF) mice transplanted with saliva from mice exposing to chronic restraint stress (CRS) displayed depression-like behavior and oral microbial dysbiosis. This was characterized by a significant differential abundance of bacterial species, including the enrichment of Pseudomonas, Pasteurellaceae, and Muribacter, as well as the depletion of Streptococcus. Metabolomic analysis showed the alternation of metabolites in the plasma of CRS-exposed GF mice, especially Eicosapentaenoic Acid. Furthermore, oral and gut barrier dysfunction caused by CRS-induced oral microbiota dysbiosis may be associated with increased blood-brain barrier permeability. Pseudomonas aeruginosa supplementation exacerbated depression-like behavior, while Eicosapentaenoic Acid treatment conferred protection against depression-like states in mice. These results suggest that oral microbiome and metabolic function dysbiosis may be relevant to the pathogenesis and pathophysiology of depression. The proposed microbiota-oral-brain axis provides a new way and targets for us to study the pathogenesis of depression.

Nematicidal Activity of 20-Deoxyingenol-3-angelate from Euphorbia peplus Latex Through Protein Kinase C Isotype TPA-1.

The latex of Euphorbia peplus and its major component 20-deoxyingenol-3-angelate (DI3A) displayed significant nematicidal activity against Caenorhabditis elegans and Panagrellus redivivus. DI3A treatment inhibited the growth and development of nematodes and caused significantly negative effects on locomotion behavior, reproduction, and accumulation of reactive oxygen species. Transcriptome analysis indicated that differential expression genes in DI3A-treated C. elegans were mainly associated with the metabolism, growth, and development process, which were further confirmed by RT-qPCR experiments. The expression level of TPA-1 gene encoding a protein kinase C isotype was obviously upregulated by DI3A treatment, and knockdown of TPA-1 by RNAi technology in the nematode could relieve the growth-inhibitory effect of DI3A. Metabolic analysis indicated that DI3A was hardly metabolized by C. elegans, but a glycosylated indole derivative was specifically accumulated likely due to the activation of detoxification. Overall, our findings suggested that DI3A from E. peplus latex exerted a potent nematicidal effect through the gene TPA-1, which provides a potential target for the control of nematodes and also suggests the potential application value of E. peplus latex and DI3A as botanical nematicides.

Measuring job stress of dental workers in China during the COVID-19 pandemic: reliability and validity of the hospital consultants' job stress questionnaire.

BACKGROUND: The Hospital Consultants' Job Stress Questionnaire (HCJSQ) has been widely used to assess sources and levels of job stress. However, its reliability and validity among Chinese dental workers have not been extensively studied. The objective of this study was to assess the reliability and validity of the HCJSQ specifically in Chinese dental workers. METHODS: The HCJSQ was used to explore the sources and the global ratings of job stress among Chinese dental workers. To assess the reliability and validity of the HCJSQ, various statistical measures were employed, including Cronbach's alpha coefficient, Spearman-Brown coefficient, Spearman correlation coefficient, exploratory factor analysis, confirmatory factor analysis, convergent validity, and discriminant validity. RESULTS: Of the participants, 526 (17.4%) reported high levels of stress, while 1,246 (41.3%) and 1,248 (41.3%) reported moderate and low levels of stress, respectively. The Cronbach's alpha coefficient for the modified HCJSQ was 0.903, and the Spearman-Brown coefficient was 0.904. Spearman correlation coefficient between individuals' items and the total score ranged from 0.438 to 0.785 (p < 0.05). Exploratory factor analysis revealed that three factors accounted for 60.243% of the total variance. Confirmatory factor analysis demonstrated factor loadings between 0.624 and 0.834 on the specified items. The fit indices of the confirmatory factor analysis indicated good model fit, with a Root Mean Square Error of Approximation of 0.064, Normative Fit Index of 0.937, Comparative Fit Index of 0.952, Incremental Fit Index of 0.952, Tucker-Lewis index of 0.941, and Goodness of Fit Index of 0.944. Additionally, the convergent validity and discriminant validity showed a good fit for the three-factor model. CONCLUSION: The results of this study confirm that Chinese dental workers experience high levels of stress, and the three-factor model of the HCJSQ proves to be a suitable instrument for evaluating the sources and levels of job stress among Chinese dental workers. Therefore, it is imperative that relevant entities such as hospitals, medical associations, and government take appropriate measures to address the existing situation.

Salivary microbiota and metabolic phenotype of patients with recurrent aphthous ulcers.

OBJECTIVES: Recurrent aphthous ulcer (RAU) is a prevalent oral mucosal disease, affecting around 20% of the global population. It can greatly impair the quality of life for affected individuals. However, the exact etiology of RAU remains unknown. SUBJECTS AND METHODS: 16S rRNA sequencing (16S rRNA-seq) and non-targeted liquid chromatography-mass spectrometry (LC-MS) were employed to investigate the salivary microbiota and metabolic phenotype between RAU patients (N = 61) and healthy controls (HCs) (N = 105). RESULTS: Findings from 16S rRNA -seq indicated reduced oral microbial diversity in RAU patients compared to HCs, but increased interactions. Clinical variables did not show any significant association with the overall diversity of oral microbiota in RAU patients. However, significant correlations were observed between specific microorganisms and clinical variables. LC-MS results revealed dysregulation of amino acid, lipid, nucleotide, and caffeine metabolism in RAU patients. Furthermore, correlation analysis of 16S rRNA-seq and LC-MS data revealed a significant association between salivary microbiota and metabolites in RAU patients. CONCLUSIONS: Our study revealed notable differences in salivary microbiota and metabolic profiles between RAU patients and HCs, indicating a strong link between oral microbiota dysbiosis, metabolic disturbances, and the onset and progression of RAU.

Chronic restraint stress promotes oral squamous cell carcinoma development by inhibiting ALDH3A1 via stress response hormone.

BACKGROUND: Chronic restraint stress (CRS) has iteratively been reported to be possibly implicated in the development of numerous cancer types. However, its role in oral squamous cell carcinoma (OSCC) has not been well elucidated. Here we intended to evaluate the role and mechanism. METHODS: The effects of CRS were investigated in xenograft models of OSCC by using transcriptome sequencing, LC-MS, ELISA and RT-PCR. Moreover, the role of CRS and ALDH3A1 on OSCC cells was researched by using Trans-well, flow cytometry, western blotting, immunofluorescence, ATP activity and OCR assay. Furthermore, immunohistochemical staining was employed to observe the cell proliferation and invasion of OSCC in xenotransplantation models. RESULTS: CRS promoted the progression of OSCC in xenograft models, stimulated the secretion of norepinephrine and the expression of ADRB2, but decreased the expression of ALDH3A1. Moreover, CRS changed energy metabolism and increased mitochondrial metabolism markers. However, ALDH3A1 overexpression suppressed proliferation, EMT and mitochondrial metabolism of OSCC cells. CONCLUSION: Inhibition of ALDH3A1 expression plays a pivotal role in CRS promoting tumorigenic potential of OSCC cells, and the regulatory of ALDH3A1 on mitochondrial metabolism may be involved in this process.

New triterpenoids from the aerial parts of the Uygur medicine Salvia deserta.

Phytochemical investigation on the aerial parts of Salvia deserta led to the isolation of eight new pentacyclic triterpenoids including three oleanane- (1 - 3) and five ursane-type (4 - 8) triterpenoids, whose structures were elucidated based on extensive spectroscopic analysis and quantum chemical calculation. Weak immunosuppressive potency was observed for compounds 1, 2, and 4 - 8 via inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced macrophages RAW264.7 at 20 µM. In addition, compounds 1, 2, and 4 - 6 exhibited moderate protective activity on t-BHP-induced oxidative injury in HepG2 cells.

Leucosceptrane Sesterterpenoids as a New Type of Natural Immunosuppressive Agents in Treating Sepsis.

Intragastric administration of the total sesterterpenoid extract (TSE) of medicinal plant Leucosceptrum canum at 2.5 g/kg dose protected mice from LPS-induced sepsis. Phytochemical investigation led to the isolation and identification of 47 leucosceptrane sesterterpenoids (1-47) including 30 new compounds (1-30) with complicated oxygenation patterns. Biological screening indicated their immunosuppressive activity via inhibiting IFN-γ secretion and/or proliferation of T cells with different potencies. Mechanism study of compounds 9, 25, and 32 revealed that they inhibited the activations of AKT-mTOR, JNK, p38 MAPK or ERK pathway in T cells and macrophages. In addition, compounds 9 and 25 induced G0/G1 cell arrest of T cells. The major component, leucosceptroid N (32), significantly lowered the levels of IL-6 and TNF-α in peripheral blood serum, and ameliorated the multiorgan damages of LPS-induced sepsis mice at 25 mg/kg dose. These findings suggest that leucosceptrane sesterterpenoids are a new type of potential immunosuppressive agents for sepsis treatment.

Potential of utilizing pathogen-derived mycotoxins as alternatives to synthetic herbicides in controlling the noxious invasive plant Xanthium italicum.

Discovery of environmentally friendly agents for controlling alien invasive species (AIS) is challenging and in urgent need as their expansion continues to increase. Xanthium italicum is a notorious invasive weed that has caused serious ecological and economic impacts worldwide. For the purpose of exploring the possibility of utilizing herbicidal mycotoxins to control this species, three compounds, a new compound, curvularioxide (1), a new naturally occurring compound, dehydroradicinin (2), and a known compound, radicinin (3), were isolated via activity-guided fractionation from the secondary metabolites of the pathogenic Curvularia inaequalis, which was found to infect X. italicum in natural habitats. All isolated compounds exhibited potent herbicidal activity on receiver species. It is noteworthy to mention that their effects on X. italicum in our bioassays were equivalent to the commercial herbicide glyphosate. Subsequent morphological analysis revealed that application of radicinin (3) severely hindered X. italicum seedlings' hypocotyl and root development. Malondialdehyde content and the activity of catalase and peroxidase of the seedlings were also significantly different from the control, implying the occurrence of induced oxidative stress. Our results suggest that pathogens infecting invasive plants might be valuable resources for developing safer herbicides for controlling weeds. © 2023 Society of Chemical Industry.

Chemical Structure Diversity and Extensive Biological Functions of Specialized Metabolites in Rice.

Rice (Oryza sativa L.) is thought to have been domesticated many times independently in China and India, and many modern cultivars are available. All rice tissues are rich in specialized metabolites (SPMs). To date, a total of 181 terpenoids, 199 phenolics, 41 alkaloids, and 26 other types of compounds have been detected in rice. Some volatile sesquiterpenoids released by rice are known to attract the natural enemies of rice herbivores, and play an indirect role in defense. Momilactone, phytocassane, and oryzalic acid are the most common diterpenoids found in rice, and are found at all growth stages. Indolamides, including serotonin, tryptamine, and N-benzoylserotonin, are the main rice alkaloids. The SPMs mainly exhibit defense functions with direct roles in resisting herbivory and pathogenic infections. In addition, phenolics are also important in indirect defense, and enhance wax deposition in leaves and promote the lignification of stems. Meanwhile, rice SPMs also have allelopathic effects and are crucial in the regulation of the relationships between different plants or between plants and microorganisms. In this study, we reviewed the various structures and functions of rice SPMs. This paper will provide useful information and methodological resources to inform the improvement of rice resistance and the promotion of the rice industry.

Discovery of Unusual Sesterterpenoids from Colquhounia coccinea var. mollis and Their Metabolic Implications.

Three unusual sesterterpenoids featuring unprecedented rearranged colquhounane (C25) and tetranorcolquhounane (C21) frameworks, colquhounoids E (1) and F (3) and norcolquhounoid F (2), were isolated from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. Their structures were elucidated by spectroscopic analysis and quantum chemical calculations. A biomimetic inspired regioselective cyclopropane cleavage was achieved under acidic conditions. The immunosuppressive activities of these new sesterterpenoids were also evaluated.

Comprehensive analysis of m6A modifications in oral squamous cell carcinoma by MeRIP sequencing.

N6-methyladenosine (m6A) modifications are the most abundant internal modifications of mRNA and have a significant role in various cancers; however, the m6A methylome profile of oral squamous cell carcinoma (OSCC) in the mRNA-wide remains unknown. In this study, we examined the relationship between m6A and OSCC. Four pairs of OSCC and adjacent normal tissues were compared by Methylated RNA immunoprecipitation sequencing (MeRIP-seq). Gene Ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Ingenuity Pathway Analysis (IPA) analyses were used to further analyze the MeRIP-seq data. A total of 2,348 different m6A peaks were identified in the OSCC group, including 85 m6A upregulated peaks and 2,263 m6A downregulated peaks. Differentially methylated m6A binding sites were enriched in the coding sequence in proximity to the stop codon of both groups. KEGG analysis revealed genes with upregulated m6A-modified sites in the OSCC group, which were prominently associated with the forkhead box O (FOXO) signaling pathway. Genes containing downregulated m6A-modified sites were significantly correlated with the PI3K/Akt signaling pathway, spliceosome, protein processing in the endoplasmic reticulum, and endocytosis. IPA analysis indicated that several genes with differential methylation peaks form networks with m6A regulators. Overall, this study established the mRNA-wide m6A map for human OSCC and indicated the potential links between OSCC and N6-methyladenosine modification.

Corrigendum: Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation.

[This corrects the article DOI: 10.3389/fonc.2023.1135879.].

Defensive furofuran lignans localized to the oil cells of Neocinnamomum delavayi and their metabolism by a specialist insect.

Neocinnamomum delavayi (Lauraceae) leaves with abundant oil cells are seldom attacked by insects, but their chemical constituent and biological function remain obscure. Three furofuran lignans, including (+)-eudesmin (3), (+)-magnolin (4), and demethoxyaschantin (5), were identified to be the major specialized metabolites in the oil cells of N. delavayi leaves through laser microdissection coupled with NMR analysis. Compounds 3 and 4 exhibited obvious antifeedant activity against a generalist insect Spodoptera exigua, and their natural contents in the leaves could effectively defend against generalist insects. Intriguingly, three specific metabolites 9-11, the O-demethylation derivates of compounds 3-5, were identified from a native specialist insect Dindica polyphaenaria feeding with N. delavayi leaves, implying an adaptation mechanism of specialist insects to plant defensive compounds. The results revealed a chemical connection between plants and insects, which would contribute to our understanding of plant-insect interaction and insect management.

Esterification with a Long-Chain Fatty Acid Elevates the Exposure Toxicity of Tigliane Diterpenoids from Euphorbia fischeriana Roots against Nematodes.

In this study, two tigliane diterpenoids, 12-deoxyphorbol-13-hexadecanoate and 12-deoxyphorbol-13-acetate (prostratin), were identified from the methanol extract of the roots of Euphorbia fischeriana and were found to have the ability to significantly reduce the survival of Caenorhabditis elegans. It was determined that exposure to these two compounds had toxic effects on the growth, reproduction, locomotion behavior, and accumulation of lipids and lipofuscin of the nematodes. Moreover, the transcription levels of the genes associated with lipid accumulation, apoptosis, insulin, and nuclear hormone synthesis in C. elegans were significantly influenced. Interestingly, 12-deoxyphorbol-13-hexadecanoate produced exposure toxicity at lower concentrations than that of prostratin. Pearson correlation analysis indicates that the elevated exposure toxicity of 12-deoxyphorbol-13-hexadecanoate may be the result of differing transcription levels, which result from the differential expression of fat-6, egl-38, and cep-1. These results reveal that esterification with a long-chain fatty acid elevates the exposure toxicity of this tigliane diterpenoid, thus providing a basis for the application of tigliane diterpenoids in plant-derived nematicides.

Clerodane diterpenoids from the Uygur medicine Salvia deserta with immunosuppressive activity.

Six undescribed clerodane diterpenoids along with five known ones were isolated from the aerial parts of Salvia deserta, a traditional Uygur medicine. Their chemical structures including absolute configurations were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, HRESIMS, and IR), combined with calculated ECD method and single-crystal X-ray diffraction analysis. All the compounds possessed a terminal α,ß-unsaturated-γ-lactone moiety, and were assayed for their immunosuppressive activity via inhibiting the secretion of cytokines TNF-α and IL-6 in macrophages RAW264.7. Among them, (5R,8R,9S,10R)-18-nor-cleroda-2,13-dien-16,15-olide-4-one obviously suppressed the secretion of TNF-α and IL-6 with IC50 values of 8.55 and 13.65 µM, respectively.

Caterpillars Detoxify Diterpenoid from Nepeta stewartiana by the Molting Hormone Gene CYP306A1.

Herbivorous insects are well known for detoxifying a broad range of the defense compounds produced by the plants that they feed on, but knowledge of the mechanisms of detoxification is still very limited. Here, we describe a system in which two species of lepidopteran caterpillars metabolize an abietane diterpene from the plants of Nepeta stewartiana Diels to an oxygenated derivative that is less active biologically. We found that this transformation could be catalyzed by a cytochrome P450 enzyme in caterpillars, which are associated with molting. Most interestingly, abietane diterpene targets the molting-associated gene CYP306A1 to alter the content of molting hormones in the insect at specific developmental stages and competitively inhibit molting hormone metabolism. These findings identify the mechanism by which caterpillars are able to detoxify abietane diterpenoid through hydroxylation at the C-19 position, which may be opening up exciting research questions into the mechanisms of interaction between plants and insects.

A new sesquiterpene synthase catalyzing the formation of (R)-ß-bisabolene from medicinal plant Colquhounia coccinea var. mollis and its anti-adipogenic and antibacterial activities.

The sesquiterpene ß-bisabolene possessing R and S configurations is commonly found in plant essential oils with antimicrobial and antioxidant activities. Here, we report the cloning and functional characterization of a (R)-ß-bisabolene synthase gene (CcTPS2) from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. The biochemical function of CcTPS2 catalyzing the cyclization of farnesyl diphosphate to form a single product (R)-ß-bisabolene was characterized through an engineered Escherichia coli producing diverse polyprenyl diphosphate precursors and in vitro enzyme assay, indicating that CcTPS2 was a high-fidelity (R)-ß-bisabolene synthase. The production of (R)-ß-bisabolene in an engineered E. coli strain harboring the exogenous mevalonate pathway, farnesyl diphosphate synthase and CcTPS1 genes was 17 mg/L under shaking flask conditions. Ultimately, 120 mg of purified (R)-ß-bisabolene was obtained from the engineered E. coli, and its structure was elucidated by detailed spectroscopic analyses (including 1D and 2D NMR, and specific rotation). Four chimeric enzymes were constructed through domain swapping, which altered the product outcome, indicating the region important for substrate and product specificity. In addition, (R)-ß-bisabolene exhibited anti-adipogenic activity in the model organism Caenorhabditis elegans and antibacterial activity selectively against Gram-positive bacteria.

Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation.

Objective: To investigate the superiority of the integrated cervicothoracic immobilization devices (ICTID) on the mobility of the supraclavicular station in lung cancer patients requiring both primary lung lesion and positive supraclavicular lymph nodes irradiation. Methods: One hundred patients with lung cancer were prospectively enrolled in the study. The following four different fixation methods are used for CT simulation positioning: thoracoabdominal flat immobilization device fixation with arms lifting (TAFID group), head-neck-shoulder immobilization device fixation with arms on the body sides (HNSID group), ICTID fixation with arms on the body sides (ICTID arms-down group), and n ICTID fixation with arms lifting (ICTID arms-up group). Cone-beam computed tomography (CBCT) images are taken daily or weekly before treatment, to assess anatomical changes during the radiotherapy course. Results: The translation errors in X (left-right direction), Y (head-foot direction), and Z (abdomen-back direction) directions of the ICTID arms-up, TAFID, ICTID arms-down and HNSID groups were (0.15 ± 0.18) cm, (0.15 ± 0.16) cm, (0.16 ± 0.16) cm, and (0.15 ± 0.20) cm; (0.15 ± 0.15) cm, (0.21 ± 0.25) cm, (0.28 ± 0.23) cm, and (0.27 ± 0.21) cm; (0.13 ± 0.14) cm, (0.15 ± 0.14) cm, (0.17 ± 0.13) cm, and (0.16 ± 0.14) cm, respectively. Among them, the ICTID arms-up group had the minimal setup errors in X direction than those in ICTID arms-down (p=0.001) and HNSID groups (p=0.001), and in Y direction than those in TAFID (p<0.001), and in Z direction than those in ICTID arms-down (p<0.001) and TAFID groups (p=0.034). For the rotational errors of the four groups in the directions of sagittal plane, transverse plane, and coronal plane, the ICTID arms-up group had the smallest setup errors in the sagittal plane than that of TAFID groups and similar rotation setup errors with those of the other three groups. Conclusion: For patients requiring radiation of primary lung lesion and positive supraclavicular lymph nodes, an integrated frame fixation device is preferred the ICTID arms-up methods provide the smallest set up error and satisfied repeatability of body position, compared with TAFID and HNSID.