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1.
Org Biomol Chem ; 22(15): 3019-3024, 2024 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-38530279

RESUMEN

An unusual pyridine-containing sesterterpenoid, leucosceptrodine (1), and five new nor-leucosceptrane sesterterpenoids, including bisnor- (C23, 2), tetranor- (C21, 3) and pentanor- (C20, 4-6) skeletons, were isolated from the leaves of Tibetan Leucosceptrum canum. Their structures including their absolute configurations were determined by extensive spectroscopic analyses and quantum chemical calculations. A single crystal of one epimer (5) was crystallized from a pair of inseparable epimers, and its structure including its absolute configuration was determined by X-ray crystallographic analysis. The immunosuppressive activities of compounds 1-4 with different potencies were evaluated by inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.


Asunto(s)
Lamiaceae , Sesterterpenos , Sesterterpenos/química , Tibet , Lamiaceae/química , Cristalografía por Rayos X , Piridinas/farmacología , Estructura Molecular
2.
J Am Mosq Control Assoc ; 40(1): 20-25, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38243835

RESUMEN

The Asian tiger mosquito, Aedes albopictus, is an important vector of chikungunya, dengue, yellow fever, and Zika viruses. Vector control remains an important means for the prevention and control of vector-borne diseases. The development of insecticide resistance has become a serious threat to the efficacy of insecticide-based control programs. To understand the resistance status and the underlying genetic mechanism in mosquitoes in Guangyuan City of Sichuan Province, China, we investigated the susceptibility of Ae. albopictus to four commonly used insecticides. We found that all the examined populations were susceptible to malathion and propoxur. However, Ae. albopictus populations in Guangyuan showed a possible resistance to the two tested pyrethroids (beta-cypermethrin and deltamethrin). Notably, phenotypic resistance to deltamethrin was detected in 2 of the 7 populations. The potential of resistance to pyrethroids was confirmed by the presence of knockdown resistance (kdr) related mutations in the voltage-gated sodium channel. Four kdr mutations (V1016G, I1532T, F1534L, and F1534S) were identified to be present alone or in combination, and their distribution displayed significant spatial heterogeneity. These findings are helpful for making evidence-based mosquito control strategies and highlight the need to regularly monitor the dynamics of pyrethroid resistance in this city.


Asunto(s)
Aedes , Insecticidas , Nitrilos , Piretrinas , Infección por el Virus Zika , Virus Zika , Animales , Mosquitos Vectores/genética , Mutación , China
3.
J Med Chem ; 67(1): 513-528, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38150591

RESUMEN

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.


Asunto(s)
Inmunosupresores , Sepsis , Animales , Ratones , Inmunosupresores/farmacología , Inmunosupresores/uso terapéutico , Inmunosupresores/metabolismo , Lipopolisacáridos/metabolismo , Macrófagos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Sepsis/inducido químicamente , Sepsis/tratamiento farmacológico
4.
J Nat Prod ; 86(11): 2468-2473, 2023 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-37939268

RESUMEN

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.


Asunto(s)
Lamiaceae , Plantas Medicinales , Análisis Espectral , Lamiaceae/química , Estructura Molecular
5.
Sci Total Environ ; 886: 164009, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37164105

RESUMEN

The changes in carbon inputs of litter and roots to forest soils caused by climate change will result in a serious cascade effect on soil respiration and its temperature sensitivity (Q10). To differentiate and quantify the effects of surface litter and living roots on soil respiration and Q10, and further explore the role of abiotic factors and microbial properties on soil respiration and Q10, a short-term (two years) detritus input and removal treatment experiment was conducted in a coniferous forest of central China. Soil temperature, soil moisture, C/N, microbial biomass and community composition were analyzed to explore the drive mechanisms of soil respiration and Q10 in response to carbon inputs. The results showed that litter addition increased soil respiration by 22 %, while litter or roots removal did not affect soil respiration, which might be ascribed to the "priming effects" mediated by fresh plant litter. We also found that litter addition increased Q10, while litter removal decreased Q10. Litter addition significantly enhanced the microbial biomass for any single functional group and altered soil microbial community composition. Structural equation model further proved that microbial biomass and community composition exerted stronger impacts on Q10 than do soil abiotic factors. Soil moisture, microbial biomass and community structure were main factors in predicting soil respiration. The study highlights the important role of litter inputs compared with living roots in carbon cycling in short-term and deepens our understanding on the complex relationships among soil respiration, soil micro-environment and microbial community composition.


Asunto(s)
Suelo , Tracheophyta , Suelo/química , Temperatura , Microbiología del Suelo , Bosques , Biomasa , Respiración , Carbono
6.
Phytochemistry ; 211: 113681, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37080413

RESUMEN

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.


Asunto(s)
Transferasas Alquil y Aril , Lamiaceae , Plantas Medicinales , Sesquiterpenos , Plantas Medicinales/metabolismo , Escherichia coli/genética , Sesquiterpenos/farmacología , Sesquiterpenos/metabolismo , Antibacterianos/farmacología , Lamiaceae/química
7.
Int J Biol Macromol ; 239: 124361, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37028629

RESUMEN

Soluble soybean polysaccharide (SSPS)-based composite films with the addition of nano zinc oxide (nZnO, 5 wt% based on SSPS) and tea tree essential oil (TTEO, 10 wt% based on SSPS) were developed by the casting method. The effect of the combination of nZnO and TTEO on the microstructure and physical, mechanical and functional properties of SSPS films was evaluated. The results showed that the SSPS/TTEO/nZnO film exhibited enhanced water vapor barrier properties, thermal stability, water resistance, surface wettability, and total color difference, and almost completely prevented ultraviolet light transmission. The addition of TTEO and nZnO had no significant effect on the tensile strength and elongation at break of the films, but decreased the percentage of light transmittance of the films at 600 nm from 85.5 % to 10.1 %. The DPPH radical scavenging activity of the films significantly increased from 46.8 % (SSPS) to 67.7 % (SSPS/TTEO/nZnO) due to the presence of TTEO. Scanning electron microscopy analysis indicated that nZnO and TTEO were evenly dispersed in the SSPS matrix. The synergistic effect of nZnO and TTEO endowed the SSPS film with excellent antibacterial activity against E. coli and S. aureus, suggesting that the SSPS/TTEO/nZnO film could be a promising material for active packaging applications.


Asunto(s)
Aceite de Árbol de Té , Óxido de Zinc , Aceite de Árbol de Té/farmacología , Glycine max/química , Árboles , Embalaje de Alimentos/métodos , Óxido de Zinc/farmacología , Óxido de Zinc/química , Escherichia coli , Staphylococcus aureus , Polisacáridos/farmacología , Polisacáridos/química ,
8.
Phytochemistry ; 210: 113642, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36933879

RESUMEN

Detailed phytochemical investigation on the traditional Chinese medicine Swertia pseudochinensis Hara led to the isolation of ten undescribed secoiridoids and fifteen known analogs. Their structures were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, and HRESIMS). Selected isolates were assayed for their anti-inflammatory and antibacterial activities, and moderate anti-inflammatory activity via inhibiting the secretion of cytokines IL-6 and TNF-α in macrophages RAW264.7 induced by LPS were observed. Antibacterial activity against Staphylococcus aureus was not found at 100 µM.


Asunto(s)
Medicamentos Herbarios Chinos , Swertia , Medicina Tradicional China , Swertia/química , Iridoides/química , Medicamentos Herbarios Chinos/farmacología , Antiinflamatorios/farmacología , Estructura Molecular
9.
Plant Cell ; 35(6): 2208-2231, 2023 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-36943781

RESUMEN

The macronutrient phosphorus is essential for plant growth and development. Plants have evolved multiple strategies to increase the efficiency of phosphate (Pi) acquisition to protect themselves from Pi starvation. However, the crosstalk between Pi homeostasis and plant development remains to be explored. Here, we report that overexpressing microRNA399 (miR399) in maize (Zea mays) is associated with premature senescence after pollination. Knockout of ZmPHO2 (Phosphate 2), a miR399 target, resulted in a similar premature senescence phenotype. Strikingly, we discovered that INDETERMINATE1 (ID1), a floral transition regulator, inhibits the transcription of ZmMIR399 genes by directly binding to their promoters, alleviating the repression of ZmPHO2 by miR399 and ultimately contributing to the maintenance of Pi homeostasis in maize. Unlike ZmMIR399 genes, whose expression is induced by Pi deficiency, ID1 expression was independent of the external inorganic orthophosphate status, indicating that ID1 is an autonomous regulator of Pi homeostasis. Furthermore, we show that ZmPHO2 was under selection during maize domestication and cultivation, resulting in a more sensitive response to Pi starvation in temperate maize than in tropical maize. Our study reveals a direct functional link between Pi-deprivation sensing by the miR399-ZmPHO2 regulatory module and plant developmental regulation by ID1.


Asunto(s)
Fosfatos , Zea mays , Zea mays/genética , Zea mays/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Plantas/metabolismo , Homeostasis/genética , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo
10.
Fitoterapia ; 165: 105402, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36577456

RESUMEN

Systematic phytochemical investigation on the Mongolian medicinal herb Lomatogonium carinthiacum led to the isolation of 12 monoterpenoids including three new secoiridoids (1, 2 and 4) and one new iridoid glycoside (13), one new monoterpenoid alkaloid (3), and three new sesquiterpenoids (14-16). Comprehensive spectroscopic analysis (including 1D and 2D NMR, and HRESIMS) and quantum chemistry computations (including ECD and NMR calculations) were applied to elucidate their structures. Weak immunosuppressive activities were observed for the new isolates via inhibiting T cell proliferation and cytokine IFN-γ secretion in vitro.


Asunto(s)
Gentianaceae , Plantas Medicinales , Estructura Molecular , Medicina Tradicional Mongoliana , Glicósidos/química , Extractos Vegetales/química , Gentianaceae/química
11.
Recent Pat Nanotechnol ; 17(2): 144-149, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35570552

RESUMEN

BACKGROUND: In this patent article, a novel bismuth tungstate/preoxidized acrylonitrile/ acrylic acid (AN/AA) copolymer composite nanofiber membrane was prepared, which was used as the visible light catalyst. METHODS: AN/AA copolymer was synthesized, which was electrospun with bismuth nitrate and sodium tungstate to prepare the composite nanofiber. Then the composite nanofiber was preoxidized to prepare the bismuth tungstate/preoxidized AN/AA composite nanofiber membrane containing adsorption moiety and photocatalytic active moiety. RESULTS: The photocatalytic activity of bismuth tungstate/preoxidized AN/AA composite nanofiber membrane with different preoxidized temperature, heating rate, and holding time by catalytic degradation of methylene blue was investigated. The optimal preoxidized conditions were as follows: the preoxidized temperature was heated to 200 °C with the heating rate of 1°C/min and the holding time at this temperature was 12 h. The chemical structure and morphology of the composite nanofiber membrane were characterized by FTIR, XRD, and SEM. CONCLUSION: The bismuth tungstate/preoxidized AN/AA composite nanofiber membrane obtained good photocatalytic properties and reusability under visible light. The degradation rate of methylene blue by this visible light catalyst could reach 90.24% for 4.5 h, and the degradation rate remained 81.53% for 4.5 h after 5 reuses.

12.
Cells ; 13(1)2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38201271

RESUMEN

The transplantation of GABAergic neuron cells has been reported to alleviate nerve pain and improve motor function after spinal cord injury (SCI). However, human mesenchymal stem cell (hMSC) differentiation into GABAergic neuron cells in a sufficient quantity remains to be accomplished. From a database screening, cAMP-responsive element-binding protein 1 (CREB1) was chosen as a potential modulator due to its critical role in the protein-protein interaction of genes related to GABAergic neural differentiation. Here, CREB1 was overexpressed in transfected hMSCs, where CREB1 could induce differentiation into GABAergic neuron cells with an upregulation of Map2 and GAD1 by 2- and 3.4-fold, respectively. Additionally, GABAergic neural differentiation was enhanced, while Notch signaling was inhibited, and BRN2 transcriptional activation played an important role in neuronal maturation. Moreover, transfected hMSCs injected into immunocompromised mice caused by CsA exhibited the neuronal markers Tuj1 and Map2 via the intraspinal route, suggesting an improvement in survival and neural differentiation. Significantly, improvement in both BMS scores (6.2 ± 1.30 vs. 4 ± 0) and thermal hyperalgesia latency (7.74 ± 2.36 s vs. 4.52 ± 0.39 s) was seen compared with the SCI naïve treatment at 4 weeks post-transplantation. Our study demonstrates that CREB1 is crucial in generating induced GABAergic neuron cells (iGNs) originating from hMSCs. Transplanting iGNs to injured spinal cord provides a promising strategy for alleviating neuropathic pain and locomotion recovery after SCI.


Asunto(s)
Células Madre Mesenquimatosas , Neuralgia , Traumatismos de la Médula Espinal , Animales , Humanos , Ratones , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Hiperalgesia , Factores Inmunológicos , Locomoción , Neuralgia/terapia , Traumatismos de la Médula Espinal/terapia
13.
ACS Omega ; 7(26): 22559-22566, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35811904

RESUMEN

Owing to the lack of donor corneas, there is an urgent need for suitable corneal substitutes. As the main component of the corneal stroma, collagen has great advantages as a corneal repair material. If there are microorganisms such as bacteria in the corneal repair material, it may induce postoperative infection, causing the failure of corneal transplantation. Therefore, irradiation, as a common sterilization method, is often used to control the microorganisms in the material. However, it has not been reported which type of radiation source and what doses can sterilize more effectively without affecting the properties of collagen-based corneal repair materials (CCRMs) and have a positive impact on macrophage polarization. In this study, three different radiation sources of ultraviolet, cobalt-60, and electron beam at four different doses of 2, 5, 8, and 10 kGy were used to irradiate CCRMs. The swelling, stretching, transmittance, and degradation of the irradiated CCRMs were characterized, and the proliferation of human corneal epithelial cells on the irradiated CCRMs was characterized using the CCK8 kit. The results showed that low dose (<5 kGy) of radiation had little effect on the performance of CCRMs. Three irradiation methods with less influence were selected for the further study on RAW264.7 macrophage polarization. The results indicated that CCRMs treated with UV could downregulate the expression of pro-inflammatory related genes and upregulate the expression of anti-inflammatory genes in macrophages, which indicated that UV irradiation is a beneficial process for the preparation of CCRMs.

14.
Arthritis Rheumatol ; 74(6): 1048-1058, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35077006

RESUMEN

OBJECTIVE: Myofiber necrosis is a significant pathologic characteristic of idiopathic inflammatory myopathies (IIMs), and its molecular mechanism is largely unknown. Necroptosis is a recently identified form of regulated necrotic cell death, and its activation might have crucial biologic consequences. The aim of the present study was to investigate the role of necroptosis in IIM muscle damage. METHODS: Western blot and immunohistochemistry analyses were performed to examine the expression of receptor-interacting protein 3 (RIP-3) and mixed-lineage kinase domain-like (MLKL) proteins in 26 IIM patients and 4 healthy controls, as well as necroptosis-related damage-associated molecular pattern molecules. Tumor necrosis factor (TNF) was used to stimulate cultured C2C12 myoblasts, and the involvement of necroptosis in cell death of C2C12 cells was studied in vitro. RESULTS: The expression of RIP-3 and MLKL proteins and their phosphorylated forms was significantly increased in the muscle tissue of IIM patients compared to that of healthy controls. The expression levels of RIP-3 and MLKL proteins were associated with the severity of muscle damage in patients with IIM. Significant colocalization of MLKL with high mobility group box chromosomal protein 1 in necrotizing myofibers was observed in muscle biopsy tissue from patients with IIM. Stimulation of C2C12 myoblasts with TNF and a pan-caspase inhibitor, Z-VAD, resulted in the overactivation of necroptosis and significantly increased necrotic cell death. Strategies involving either inhibition of necroptosis with necrostatin-1 or knockdown of MLKL expression successfully prevented necroptosis-induced cell death of C2C12 cells. CONCLUSION: These findings demonstrate that overactivated necroptosis contributes to muscle damage in IIMs and suggest that necroptosis inhibitors could represent a new therapeutic target in the treatment of IIMs.


Asunto(s)
Miositis , Necroptosis , Apoptosis , Muerte Celular , Humanos , Necrosis , Proteínas Quinasas/química , Proteínas Quinasas/metabolismo , Factor de Necrosis Tumoral alfa
15.
Sci Total Environ ; 806(Pt 4): 150957, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34656582

RESUMEN

Changes in soil microbial community play an irreplaceable role in regulating nutrient cycling that shapes forest ecosystem responses to climate change. However, if the effect of experimental warming on soil microorganisms depends upon soil water availability, which is closely related to soil depth is generally not well decumented. We conducted an in situ simulation experiment in an oak forest to determine the response pattern of soil microbial community to manipulated drought and warming at different soil depths. The responses of soil microbial communities to reduced precipitation and soil warming were highly dependent upon soil depth. Reduced precipitation remarkably elevated top-soil microbial biomass carbon (MBC) and nitrogen (MBN) in the unwarmed plots but no effects occured in the warmed plots. Soil warming showed positive effects on top-soil MBC and MBN under ambient precipitation, whereas negative ones were found under decreased precipitation. Neither reduced precipitation nor soil warming displayed effects on sub-soil MBC and MBN. Reduced precipitation notably increased soil total phospholipid fatty acids (PLFA) as well as that of bacterial and gram-negative bacterial only at top-soil in the unwarmed plots. Soil warming showed positive effects on total PLFA, bacterial PLFA, and gram-negative bacterial PLFA at both top- and sub-soil under ambient precipitation. We found that the interactive effects of climate change on soil microorganisms varied with soil depth, indicating that multilayer soil models should be considered while assessing the relationship between soil and atmosphere carbon exchange. Further research is expected to explore the long-term response of soil microorganisms in soil vertical profiles to climate change.


Asunto(s)
Microbiota , Quercus , Carbono , Ecosistema , Bosques , Suelo , Microbiología del Suelo
16.
Sci Total Environ ; 806(Pt 4): 150939, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655623

RESUMEN

Litter decomposition is a critical process of biogeochemical cycles of ecosystem. While growing evidences have shown the decomposition rates of litter mixture are different from those of single-species litters, the mutual effects between different functional type species in the mixture remain inconclusive. A field litterbag experiment was conducted to determine the mutual effects of three functional type plants [tree (Quercus variabilis), shrub (Lindera glauca), and herb (Lygodium japonicum)] during the decomposition in a temperate oak forest. After 400 days of in situ incubation, the mass loss rate of each species-specific in the mixture was greater than that decomposed as monoculture, showing the greatest mass loss in the three-species litter mixture. In addition, the decomposition constant for each species was stimulated while mixed with other species. The presence of L. glauca leaf litter significantly elevated total N (15.0%) and C loss (8.92%) of Q. variabilis leaf litter, and the existence of Q. variabilis leaf litter also led to enhanced total N (10.4%) and C (9.1%) release of L. glauca leaf litter. The addition of L. japonicum in the mixed litters showed substantially positive effects on total N (16.5% and 10.8%) and C (10.6% and 14.2%) release of both L. glauca and Q. variabilis litters. In contrast, neither Q. variabilis nor L. glauca litter exhibited effects on the total N and C loss of L. japonicum litter. Our results indicate that the mutual effects between different functional types on nutrient release were asymmetric in the mixed litters. The role of species-specific in the mixture should be highlighted while evaluated the nonadditive effects in the leaf litter mixing experiments.


Asunto(s)
Quercus , Árboles , Ecosistema , Bosques , Hojas de la Planta
17.
Plant Commun ; 2(5): 100233, 2021 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-34746763

RESUMEN

Terpenoids are the largest class of natural products with complex structures and extensive bioactivities; their scaffolds are generated by diverse terpenoid synthases (TPSs) from a limited number of isoprenoid diphosphate precursors. Promiscuous TPSs play important roles in the evolution of terpenoid chemodiversity, but they remain largely unappreciated. Here, an extremely promiscuous terpenoid synthase (CcTPS1) of the TPS-b subfamily was cloned and functionally characterized from a leaf-specific transcriptome of the Lamiaceae plant Colquhounia coccinea var. mollis. CcTPS1 is the first sester-/di-/sesqui-/mono-TPS identified from the plant kingdom, accepting C25/C20/C15/C10 diphosphate substrates to generate a panel of sester-/di-/sesqui-/mono-terpenoids. Engineered Escherichia coli expressing CcTPS1 produced three previously unreported terpenoids (two sesterterpenoids and a diterpenoid) with rare cyclohexane-containing skeletons, along with four sesquiterpenoids and one monoterpenoid. Their structures were elucidated by extensive nuclear magnetic resonance spectroscopy. Nicotiana benthamiana transiently expressing CcTPS1 also produced the diterpenoid and sesquiterpenoids, demonstrating the enzyme's promiscuity in planta. Its highly leaf-specific expression pattern combined with detectable terpenoid products in leaves of C. coccinea var. mollis and N. benthamiana expressing CcTPS1 suggested that CcTPS1 was mainly responsible for diterpenoid and sesquiterpenoid biosynthesis in plants. CcTPS1 expression and the terpenoid products could be induced by methyl jasmonate, suggesting their possible role in plant-environment interaction. CcTPS1 was localized to the cytosol and may differ from mono-TPSs in subcellular compartmentalization and substrate tolerance. These findings will greatly aid our understanding of plant TPS evolution and terpenoid chemodiversity; they also highlight the enormous potential of transcriptome mining and heterologous expression for the exploration of unique enzymes and natural products hidden in plants.


Asunto(s)
Transferasas Alquil y Aril/genética , Lamiaceae/genética , Proteínas de Plantas/genética , Terpenos/metabolismo , Transferasas Alquil y Aril/metabolismo , Lamiaceae/enzimología , Lamiaceae/metabolismo , Proteínas de Plantas/metabolismo
18.
Org Lett ; 23(19): 7462-7466, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34505790

RESUMEN

Two novel triterpenoid saponins, colqueleganoids A (1) and B (2), with the first methyl-30 incorporated 6/6/6/6-cyclized carbon skeleton (named colquelegane), were isolated from the root of Colquhounia elegans. Their structures including absolute configuration were determined by spectroscopic methods and X-ray crystallographic analyses. Interestingly, both compounds significantly enhanced TNF-α production and 1 also increased the IL-6 production in RAW264.7 macrophages stimulated with lipopolysaccharide (LPS), suggesting their potential application as immunostimulants in immunotherapy and vaccination.


Asunto(s)
Antiinflamatorios/farmacología , Lipopolisacáridos/química , Saponinas/farmacología , Triterpenos/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Ciclización , Lamiaceae/metabolismo , Macrófagos/metabolismo , Estructura Molecular , Saponinas/química , Saponinas/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificación
19.
Angew Chem Int Ed Engl ; 60(48): 25468-25476, 2021 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-34580976

RESUMEN

A versatile terpene synthase (LcTPS2) producing unconventional macrocyclic terpenoids was characterized from Leucosceptrum canum. Engineered Escherichia coli and Nicotiana benthamiana expressing LcTPS2 produced six 18-/14-membered sesterterpenoids including five new ones and two 14-membered diterpenoids. These products represent the first macrocyclic sesterterpenoids from plants and the largest sesterterpenoid ring system identified to date. Two variants F516A and F516G producing approximately 3.3- and 2.5-fold, respectively, more sesterterpenoids than the wild-type enzyme were engineered. Both 18- and 14-membered ring sesterterpenoids displayed significant inhibitory activity on the IL-2 and IFN-γ production of T cells probably via inhibition of the MAPK pathway. The findings will contribute to the development of efficient biocatalysts to create bioactive macrocyclic sesterterpenoids, and also herald a new potential in the well-trodden territory of plant terpenoid biosynthesis.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Inmunosupresores/farmacología , Interferón gamma/antagonistas & inhibidores , Interleucina-2/antagonistas & inhibidores , Compuestos Macrocíclicos/farmacología , Terpenos/farmacología , Humanos , Inmunosupresores/química , Inmunosupresores/metabolismo , Interferón gamma/biosíntesis , Interleucina-2/biosíntesis , Lamiaceae/química , Lamiaceae/metabolismo , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/metabolismo , Estructura Molecular , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Terpenos/química , Terpenos/metabolismo
20.
Phytochemistry ; 192: 112961, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34592512

RESUMEN

Two undescribed secoiridoids (dehydroxyl-swerimilegenin H and 9-oxo-swerimuslactone A) with eight known ones, and two undescribed triterpenoids [28-O-(3,4-dihydroxyl-benzyl)-lupeol and 17-hydroperoxide-28-norurs-12-en-3-one] with seven known ones, were isolated from the aerial parts of Gentiana veitchiorum, a traditional Tibetan medicine. The structures of these compounds were elucidated by detailed spectroscopic analyses (including 1D and 2D NMR, HRMS, IR, and specific rotation) and comparison with structurally related known compounds. The isolates were selected to evaluate for their immunosuppressive activity via inhibiting the proliferation of T cells and cytokine IFN-γ production in T cells. Among them, 28-O-(3,4-dihydroxyl-benzyl)-lupeol exhibited significant effect by inhibiting the proliferation of T cells (IC50, 20.08 µM) and T cell IFN-γ production (IC50, 7.29 µM).


Asunto(s)
Gentiana , Triterpenos , Iridoides , Medicina Tradicional Tibetana , Estructura Molecular , Extractos Vegetales
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