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1.
Microb Cell Fact ; 23(1): 3, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172890

RESUMO

BACKGROUND: Antibiotics biosynthesis is usually regulated by the cluster-situated regulatory gene(s) (CSRG(s)), which directly regulate the genes within the corresponding biosynthetic gene cluster (BGC). Previously, we have demonstrated that LmbU functions as a cluster-situated regulator (CSR) of lincomycin. And it has been found that LmbU regulates twenty non-lmb genes through comparative transcriptomic analysis. However, the regulatory mode of CSRs' targets outside the BGC remains unknown. RESULTS: We screened the targets of LmbU in the whole genome of Streptomyces lincolnensis and found fourteen candidate targets, among which, eight targets can bind to LmbU by electrophoretic mobility shift assays (EMSA). Reporter assays in vivo revealed that LmbU repressed the transcription of SLINC_0469 and SLINC_1037 while activating the transcription of SLINC_8097. In addition, disruptions of SLINC_0469, SLINC_1037, and SLINC_8097 promoted the production of lincomycin, and qRT-PCR showed that SLINC_0469, SLINC_1037, and SLINC_8097 inhibited transcription of the lmb genes, indicating that all the three regulators can negatively regulate lincomycin biosynthesis. CONCLUSIONS: LmbU can directly regulate genes outside the lmb cluster, and these genes can affect both lincomycin biosynthesis and the transcription of lmb genes. Our results first erected the cascade regulatory circuit of LmbU and regulators outside lmb cluster, which provides the theoretical basis for the functional research of LmbU family proteins.


Assuntos
Proteínas de Bactérias , Streptomyces , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lincomicina , Streptomyces/genética , Streptomyces/metabolismo , Transcriptoma , Regulação Bacteriana da Expressão Gênica , Antibacterianos/farmacologia , Antibacterianos/metabolismo
2.
Molecules ; 29(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611896

RESUMO

The crystal phase, alongside the composition, morphology, architecture, facet, size, and dimensionality, has been recognized as a critical factor influencing the properties of noble metal nanomaterials in various applications. In particular, unconventional crystal phases can potentially enable fascinating properties in noble metal nanomaterials. Recent years have witnessed notable advances in the phase engineering of nanomaterials (PEN). Within the accessible strategies for phase engineering, the effect of strain cannot be ignored because strain can act not only as the driving force of phase transition but also as the origin of the diverse physicochemical properties of the unconventional crystal phase. In this review, we highlight the development of unconventional crystal-phase noble metal nanomaterials within strain engineering. We begin with a short introduction of the unconventional crystal phase and strain effect in noble metal nanomaterials. Next, the correlations of the structure and performance of strain-engineered unconventional crystal-phase noble metal nanomaterials in electrocatalysis are highlighted, as well as the phase transitions of noble metal nanomaterials induced by the strain effect. Lastly, the challenges and opportunities within this rapidly developing field (i.e., the strain engineering of unconventional crystal-phase noble metal nanocatalysts) are discussed.

3.
Plant Biotechnol J ; 21(7): 1479-1495, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37170717

RESUMO

Heterosis refers to the better performance of cross progeny compared with inbred parents, and its utilization contributes greatly to agricultural production. Several hypotheses have been proposed to explain heterosis mainly including dominance, over-dominance (or pseudo-overdominance) and epistasis. However, systematic dissection and verification of these hypotheses are rarely documented. Here, comparison of heterosis level across different traits showed that the strong heterosis of composite traits (such as yield) could be attributed to the multiplicative effects of moderate heterosis of component traits, whether at the genome or locus level. Yield heterosis was regulated by a complex trait-QTL network that was characterized by obvious centre-periphery structure, hub QTL, complex up/downstream and positive/negative feedback relationships. More importantly, we showed that better-parent heterosis on yield could be produced in a cross of two near-isogenic lines by the pyramiding and complementation of two major heterotic QTL showing partial-dominance on yield components. The causal gene (BnaA9.CYP78A9) of QC14 was identified, and its heterotic effect results from the heterozygous status of a CACTA-like transposable element in its upstream regulatory region, which led to partial dominance at expression and auxin levels, thus resulting in non-additive expression of downstream responsive genes involved in cell cycle and proliferation, eventually leading to the heterosis of cell number. Taken together, the results at the phenotypic, genetic and molecular levels were highly consistent, which demonstrated that the pyramiding effect of heterotic QTL and the multiplicative effect of individual component traits could well explain substantial parts of yield heterosis in oilseed rape. These results provide in-depth insights into the genetic architecture and molecular mechanism of yield heterosis.


Assuntos
Vigor Híbrido , Locos de Características Quantitativas , Vigor Híbrido/genética , Mapeamento Cromossômico , Locos de Características Quantitativas/genética , Fenótipo , Heterozigoto
4.
J Med Virol ; 95(1): e28294, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367155

RESUMO

The global monkeypox outbreak in 2022 has severely affected the life and health of people. Currently, partial smallpox vaccines have been approved for monkeypox prevention. Considering the potential occupational health risks of monkeypox infection among healthcare workers (HCWs), this study explored the willingness of Chinese HCWs to receive the monkeypox vaccine and analyzed the factors influencing their decision. We conducted an online cross-sectional survey among HCWs of 10 Chinese hospitals from May 30th, 2022 to August 1st, 2022. Specifically, a self-report questionnaire was administered to evaluate the attitude and acceptance of HCWs toward the monkeypox vaccine, followed by a multivariate logistic regression analysis to determine the independent predictors of vaccination. The survey included 1032 participants, of whom 90.12% expressed their willingness for vaccination (vaccine hesitancy rate = 9.88%). Univariate analysis showed that 11 variables differed significantly between the vaccine acceptance and vaccine hesitancy groups. Multivariate logistic regression analysis demonstrated that the age of 30-40 years (odds ratio [OR] = 0.504, 95% confidence interval [CI]: 0.284-0.893, p = 0.019 vs. age of <30 years old), working in a secondary hospital (OR = 0.449, 95% CI: 0.249-0.808, p = 0.019 vs. working in a tertiary hospital), considering vaccination necessary for controlling monkeypox infection (OR = 4.135, 95% CI: 2.109-8.106, p < 0.001 vs. not considering it necessary), willingness to pay for the monkeypox vaccine (OR = 2.125, 95% CI: 1.206-3.745, p = 0.009 vs. no willingness to pay), considering implementation of mandatory vaccination necessary (OR = 1.990, 95% CI: 1.023-3.869, p = 0.043 vs. not considering it necessary), and recommending family members and friends to take the vaccine (OR = 13.847, 95% CI: 7.487-25.609, p < 0.001 vs. not recommending) were crucial independent predictors of the willingness to receive monkeypox-related vaccination. This study evaluated the acceptance and hesitancy rates of Chinese HCWs toward the monkeypox vaccine and found that the willingness to receive vaccination was mainly correlated to age, hospital level, and attitude toward vaccination. Therefore, to promote vaccine absorption, we recommend expanding publicity, formulating reasonable policies, and improving the recognition of vaccines.


Assuntos
Mpox , Vacina Antivariólica , Vacinas , Humanos , Adulto , Estudos Transversais , Mpox/prevenção & controle , Vacinação , Pessoal de Saúde , Centros de Atenção Terciária
5.
Appl Microbiol Biotechnol ; 107(24): 7501-7514, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768348

RESUMO

The Actinomycetes Streptomyces lincolnensis is the producer of lincosamide-type antibiotic lincomycin, a widely utilized drug against Gram-positive bacteria and protozoans. In this work, through gene knockout, complementation, and overexpression experiments, we identified LcbR1 (SLINC_1595), a GntR family transcriptional regulator, as a repressor for lincomycin biosynthesis. Deletion of lcbR1 boosted lincomycin production by 3.8-fold, without obvious change in morphological development or cellular growth. The homologues of LcbR1 are widely distributed in Streptomyces. Heterologous expression of SCO1410 from Streptomyces coelicolor resulted in the reduction of lincomycin yield, implying that the function of LcbR1 is conserved across different species. Alignment among sequences upstream of lcbR1 and their homologues revealed a conserved 16-bp palindrome (-TTGAACGATCCTTCAA-), which was further proven to be the recognition motif of LcbR1 by electrophoretic mobility shift assays (EMSAs). Via this motif, LcbR1 suppressed the transcription of lcbR1 and SLINC_1596 sharing the same bi-directional promoter. SLINC_1596, one important target of LcbR1, exerted a positive effect on lincomycin production. As detected by quantitative real-time PCR (qRT-PCR) analyses, the expressions of all selected structural (lmbA, lmbC, lmbJ, lmbV, and lmbW), resistance (lmrA and lmrB) and regulatory genes (lmrC and lmbU) from lincomycin biosynthesis cluster were upregulated in deletion strain ΔlcbR1 at 48 h of fermentation, while the mRNA amounts of bldD, glnR, ramR, SLCG_Lrp, and SLCG_2919, previously characterized as the regulators on lincomycin production, were decreased in strain ΔlcbR1, although the regulatory effects of LcbR1 on the above differential expression genes seemed to be indirect. Besides, indicated by EMSAs, the expression of lcbR1 might be regulated by GlnR, SLCG_Lrp, and SLCG_2919, which shows the complexity of the regulatory network on lincomycin biosynthesis. KEY POINTS: • LcbR1 is a novel and conservative GntR family regulator regulating lincomycin production. • LcbR1 modulates the expressions of lcbR1 and SLINC_1596 through a palindromic motif. • GlnR, SLCG_Lrp, and SLCG_2919 can control the expression of lcbR1.


Assuntos
Streptomyces coelicolor , Streptomyces , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lincomicina , Antibacterianos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Regulação Bacteriana da Expressão Gênica , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo
6.
Appl Microbiol Biotechnol ; 107(9): 2933-2945, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36930277

RESUMO

Lincomycin is a broad-spectrum antibiotic and particularly effective against Gram-positive pathogens. Albeit familiar with the biosynthetic mechanism of lincomycin, we know less about its regulation, limiting the rational design for strain improvement. We therefore analyzed two-component systems (TCSs) in Streptomyces lincolnensis, and selected eight TCS gene(s) to construct their deletion mutants utilizing CRISPR/Cas9 system. Among them, lincomycin yield increased in two strains (Δ3900-3901 and Δ5290-5291) while decreased in other four strains (Δ3415-3416, Δ4153-4154, Δ4985, and Δ7949). Considering the conspicuous effect, SLINC_5291-5290 (AflQ1-Q2) was subsequently studied in detail. Its repression on lincomycin biosynthesis was further proved by gene complementation and overexpression. By binding to a 16-bp palindromic motif, the response regulator AflQ1 inhibits the transcription of its encoding gene and the expression of eight operons inside the lincomycin synthetic cluster (headed by lmbA, lmbJ, lmbK, lmbV, lmbW, lmbU, lmrA, and lmrC), as demonstrated by quantitative RT-PCR and electrophoretic mobility shift assays. Besides, the regulatory genes including bldD, glnR, lcbR1, and ramR are also regulated by the TCS. According to the screening towards nitrogen sources, aspartate affects the regulatory behavior of histidine kinase AflQ2. And in return, AflQ1 accelerates aspartate metabolism via ask-asd, asd2, and thrA. In summary, we acquired six novel regulators related to lincomycin biosynthesis, and elucidated the regulatory mechanism of AflQ1-Q2. This highly conserved TCS is a promising target for the construction of antibiotic high-yield strains. KEY POINTS: • AflQ1-Q2 is a repressor for lincomycin production. • AflQ1 modulates the expression of lincomycin biosynthetic and regulatory genes. • Aspartate affects the behavior of AflQ2, and its metabolism is promoted by AflQ1.


Assuntos
Ácido Aspártico , Proteínas de Bactérias , Ácido Aspártico/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lincomicina , Antibacterianos , Regulação Bacteriana da Expressão Gênica
7.
Biosci Biotechnol Biochem ; 87(7): 786-795, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37076767

RESUMO

AtrA belongs to the TetR family and has been well characterized for its roles in antibiotic biosynthesis regulation. Here, we identified an AtrA homolog (AtrA-lin) in Streptomyces lincolnensis. Disruption of atrA-lin resulted in reduced lincomycin production, whereas the complement restored the lincomycin production level to that of the wild-type. In addition, atrA-lin disruption did not affect cell growth and morphological differentiation. Furthermore, atrA-lin disruption hindered the transcription of regulatory gene lmbU, structural genes lmbA and lmbW inside the lincomycin biosynthesis gene cluster, and 2 other regulatory genes, adpA and bldA. Completement of atrA-lin restored the transcription of these genes to varying degrees. Notably, we found that AtrA-lin directly binds to the promoter region of lmbU. Collectively, AtrA-lin positively modulated lincomycin production via both pathway-specific and global regulators. This study offers further insights into the functional diversity of AtrA homologs and the mechanism of lincomycin biosynthesis regulation.


Assuntos
Lincomicina , Streptomyces , Lincomicina/farmacologia , Lincomicina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Regulação Bacteriana da Expressão Gênica , Antibacterianos/metabolismo
8.
Neural Plast ; 2023: 7768980, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101904

RESUMO

Objective: Epilepsy may cause chronic cognitive impairment by disturbing sleep plasticity. Sleep spindles play a crucial role in sleep maintenance and brain plasticity. This study explored the relationship between cognition and spindle characteristics in adult epilepsy. Methods: Participants underwent one-night sleep electroencephalogram recording and neuropsychological tests on the same day. Spindle characteristics during N2 sleep were extracted using a learning-based system for sleep staging and an automated spindle detection algorithm. We investigated the difference between cognitive subgroups in spindle characteristics. Multiple linear regressions were applied to analyze associations between cognition and spindle characteristics. Results: Compared with no/mild cognitive impairment, epilepsy patients who developed severe cognitive impairment had lower sleep spindle density, the differences mainly distributed in central, occipital, parietal, middle temporal, and posterior temporal (P < 0.05), and had relatively long spindle duration in occipital and posterior temporal (P < 0.05). Mini-Mental State Examination (MMSE) was associated with spindle density (pars triangularis of the inferior frontal gyrus (IFGtri): ß = 0.253, P = 0.015, and P.adjust = 0.074) and spindle duration (IFGtri: ß = -0.262, P = 0.004, and P.adjust = 0.030). Montreal Cognitive Assessment (MoCA) was associated with spindle duration (IFGtri: ß = -0.246, P = 0.010, and P.adjust = 0.055). Executive Index Score (MoCA-EIS) was associated with spindle density (IFGtri: ß = 0.238, P = 0.019, and P.adjust = 0.087; parietal: ß = 0.227, P = 0.017, and P.adjust = 0.082) and spindle duration (parietal: ß = -0.230, P = 0.013, and P.adjust = 0.065). Attention Index Score (MoCA-AIS) was associated with spindle duration (IFGtri: ß = -0.233, P = 0.017, and P.adjust = 0.081). Conclusions: The findings suggested that the altered spindle activity in epilepsy with severe cognitive impairment, the associations between the global cognitive status of adult epilepsy and spindle characteristics, and specific cognitive domains may relate to spindle characteristics in particular brain regions.


Assuntos
Disfunção Cognitiva , Epilepsia , Humanos , Adulto , Cognição , Encéfalo , Sono , Disfunção Cognitiva/psicologia , Epilepsia/complicações , Testes Neuropsicológicos
9.
BMC Biol ; 20(1): 276, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482461

RESUMO

BACKGROUND: Decidualization refers to the process of transformation of endometrial stromal fibroblast cells into specialized decidual stromal cells that provide a nutritive and immunoprivileged matrix essential for blastocyst implantation and placental development. Deficiencies in decidualization are associated with a variety of pregnancy disorders, including female infertility, recurrent implantation failure (RIF), and miscarriages. Despite the increasing number of genes reportedly associated with endometrial receptivity and decidualization, the cellular and molecular mechanisms triggering and underlying decidualization remain largely unknown. Here, we analyze single-cell transcriptional profiles of endometrial cells during the window of implantation and decidual cells of early pregnancy, to gains insights on the process of decidualization. RESULTS: We observed a unique IGF1+ stromal cell that may initiate decidualization by single-cell RNA sequencing. We found the IL1B+ stromal cells promote gland degeneration and decidua hemostasis. We defined a subset of NK cells for accelerating decidualization and extravillous trophoblast (EVT) invasion by AREG-IGF1 and AREG-CSF1 regulatory axe. Further analysis indicates that EVT promote decidualization possibly by multiply pathways. Additionally, a systematic repository of cell-cell communication for decidualization was developed. An aberrant ratio conversion of IGF1+ stromal cells to IGF1R+ stromal cells is observed in unexplained RIF patients. CONCLUSIONS: Overall, a unique subpopulation of IGF1+ stromal cell is involved in initiating decidualization. Our observations provide deeper insights into the molecular and cellular characterizations of decidualization, and a platform for further development of evaluation of decidualization degree and treatment for decidualization disorder-related diseases.


Assuntos
Placenta , Células Estromais , Gravidez , Humanos , Feminino , Fator de Crescimento Insulin-Like I/genética
10.
J Basic Microbiol ; 63(6): 622-631, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36734183

RESUMO

Lincomycin is one of the most important antibiotics. However, transcriptional regulation network of secondary metabolism in Streptomyces lincolnensis, the lincomycin producer, remained obscure. AdpA from S. lincolnensis (namely AdpAlin ) has been proved to activate lincomycin biosynthesis. Here we found that both lincomycin and melanin took l-tyrosine as precursor, and AdpAlin activated melanin biosynthesis as well. Three tyrosinases, MelC2, MelD2, and MelE, and one tyrosine peroxygenase, LmbB2, participated in lincomycin and melanin biosynthesis in different ways. For melanin biosynthesis, MelC2 was the only key enzyme required. For lincomycin biosynthesis, MelD2 and LmbB2 were positive factors and were suggested to convert l-tyrosine to l-dihydroxyphenylalanine (l-DOPA). Otherwise, MelC2 and MelE were negative factors for lincomycin biosynthesis and they were supposed to oxidize l-DOPA to generate melanin and certain unknown metabolite, respectively. Based on in silico analysis combined with electrophoretic mobility shift assays (EMSAs), we proved that AdpAlin directly interacted with promoters of melC, melD, and melE by binding to putative AdpA-binding sites in vitro. Moreover, in vivo experiments revealed that AdpAlin positively regulated the transcription of melC and melE, but negatively regulated melD. In conclusion, AdpAlin was the switch of secondary metabolism in S. lincolnensis, and it modulated precursor flux of lincomycin and melanin biosynthesis by directly activating melC, melE, and lmbB1/lmbB2 or repressing melD.


Assuntos
Lincomicina , Melaninas , Melaninas/metabolismo , Metabolismo Secundário , Levodopa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Tirosina/metabolismo
11.
J Basic Microbiol ; 63(2): 190-199, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36453540

RESUMO

Lincomycin produced by Streptomyces lincolnensis is a critical antibacterial antibiotic in the clinical. To further understand the regulatory mechanism of lincomycin biosynthesis, we identified an alternative σ factor, σL sl , in Streptomyces lincolnensis NRRL 2936. Deletion of sigLsl resulted in an increase in cell growth but a decrease in lincomycin production. σL sl boosted lincomycin biosynthesis by directly stimulating the transcription of four genes (lmbD, lmbV, lmrC, and lmbU) within the lincomycin biosynthetic lmb gene cluster. Besides, σL sl participated in lincomycin biosynthesis by directly stimulating the transcription of mshC, a gene responsible for MSH synthesis. In conclusion, our findings demonstrated that σL sl plays a direct regulatory role in lincomycin biosynthesis. This study extends the understanding of molecular mechanisms of lincomycin biosynthetic regulation.


Assuntos
Lincomicina , Fator sigma , Fator sigma/genética , Proteínas de Bactérias/genética , Antibacterianos
12.
Int J Mol Sci ; 24(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37108349

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder clinically defined by motor instability, bradykinesia, and resting tremors. The clinical symptomatology is seen alongside pathologic changes, most notably the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the accumulation of α-synuclein and neuromelanin aggregates throughout numerous neural circuits. Traumatic brain injury (TBI) has been implicated as a risk factor for developing various neurodegenerative diseases, with the most compelling argument for the development of PD. Dopaminergic abnormalities, the accumulation of α-synuclein, and disruptions in neural homeostatic mechanisms, including but not limited to the release of pro-inflammatory mediators and the production of reactive oxygen species (ROS), are all present following TBI and are closely related to the pathologic changes seen in PD. Neuronal iron accumulation is discernable in degenerative and injured brain states, as is aquaporin-4 (APQ4). APQ4 is an essential mediator of synaptic plasticity in PD and regulates edematous states in the brain after TBI. Whether the cellular and parenchymal changes seen post-TBI directly cause neurodegenerative diseases such as PD is a point of considerable interest and debate; this review explores the vast array of neuroimmunological interactions and subsequent analogous changes that occur in TBI and PD. There is significant interest in exploring the validity of the relationship between TBI and PD, which is a focus of this review.


Assuntos
Lesões Encefálicas Traumáticas , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo , Neuroimunomodulação , Doenças Neurodegenerativas/patologia , Neurônios Dopaminérgicos/metabolismo , Lesões Encefálicas Traumáticas/patologia , Substância Negra/metabolismo
13.
Molecules ; 28(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37570700

RESUMO

The roots of Astilbe grandis, known as "Ma sang gou bang", are used as a Miao traditional medicine with anti-inflammatory and analgesic properties. However, the active components and mechanism of action of this plant remain mostly uncharacterized. The aim of this study was to identify its active components and verify their pharmacological activity. The extract of A. grandis root was separated using various chromatographic methods. As a result, we obtained one novel triterpenoid, named astigranlactone (1), which has an unusual lactone moiety formed between C-7 and C-27. Additionally, a known coumarin compound, 11-O-galloyl bergenin (2) was isolated from this plant. The structures of these two compounds were elucidated by extensive NMR experiments in conjunction with HR-ESI-MS data. To the best of our knowledge, both compounds were isolated from this species for the first time. Moreover, we tested the anti-inflammation effect of the two compounds by establishing a cellular inflammation model induced by LPS in RAW264.7 cells. The effect of different concentrations of these compounds on the activity of RAW264.7 cells was assessed using a CCK8 assay. The levels of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) in the supernatant of each group were evaluated using the Griess method and an enzyme-linked immunosorbent assay (ELISA). Western blot and quantitative real-time PCR (qRT-RCR) were used to measure the levels of cyclooxygenase 2 (COX-2) and nitric oxide synthase (iNOS) gene expression. Our findings revealed that these two compounds inhibited the high levels of NO, TNF-α, IL-6, IL-1ß, COX-2, and iNOS (induced by LPS). Mechanistic studies demonstrated that these two compounds reduced the activation of the nuclear transcription factor-B (NF-κB) signaling pathway by inhibiting the phosphorylation of p65. Therefore, our study indicates that compounds 1 and 2 can exert a definite anti-inflammatory effect by inhibiting the NF-κB signaling pathway.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Macrófagos , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Cumarínicos/farmacologia , Cumarínicos/metabolismo , Óxido Nítrico/metabolismo
14.
World J Microbiol Biotechnol ; 39(12): 332, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37801155

RESUMO

Regulators belonging to the DeoR family are widely distributed among the bacteria. Few studies have reported that DeoR family proteins regulate secondary metabolism of Streptomyces. This study explored the function of DeoR (SLINC_8027) in Streptomyces lincolnensis. Deletion of deoR in NRRL 2936 led to an increase in cell growth. The lincomycin production of the deoR deleted strain ΔdeoR was 3.4-fold higher than that of the wild strain. This trait can be recovered to a certain extent in the deoR complemented strain ΔdeoR::pdeoR. According to qRT-PCR analysis, DeoR inhibited the transcription of all detectable genes in the lincomycin biosynthesis cluster and repressed the expression of glnR, bldD, and SLCG_Lrp, which encode regulators outside the cluster. DeoR also inhibited the transcription of itself, as revealed by the XylE reporter. Furthermore, we demonstrated that DeoR bound directly to the promoter region of deoR, lmbA, lmbC-D, lmbJ-K, lmrA, lmrC, glnR, and SLCG_Lrp, by recognizing the 5'-CGATCR-3' motif. This study found that versatile regulatory factor DeoR negatively regulates lincomycin biosynthesis and cellular growth in S. lincolnensis, which expanded the regulatory network of lincomycin biosynthesis.


Assuntos
Lincomicina , Streptomyces , Lincomicina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Metabolismo Secundário , Regulação Bacteriana da Expressão Gênica
15.
J Neurosci ; 41(36): 7532-7545, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34326141

RESUMO

Acetaldehyde (ACD), the first metabolite of ethanol, is implicated in several of ethanol's actions, including the reinforcing and aversive effects. The neuronal mechanisms underlying ACD's aversive effect, however, are poorly understood. The lateral habenula (LHb), a regulator of midbrain monoaminergic centers, is activated by negative valence events. Although the LHb has been linked to the aversive responses of several abused drugs, including ethanol, little is known about ACD. We, therefore, assessed ACD's action on LHb neurons in rats. The results showed that intraperitoneal injection of ACD increased cFos protein expression within the LHb and that intra-LHb infusion of ACD induced conditioned place aversion in male rats. Furthermore, electrophysiological recording in brain slices of male and female rats showed that bath application of ACD facilitated spontaneous firing and glutamatergic transmission. This effect of ACD was potentiated by an aldehyde dehydrogenase (ALDH) inhibitor, disulfiram (DS), but attenuated by the antagonists of dopamine (DA) receptor (DAR) subtype 1 (SCH23390) and subtype 2 (raclopride), and partly abolished by the pretreatment of DA or DA reuptake blocker (GBR12935; GBR). Moreover, application of ACD initiated a depolarizing inward current (IACD) and enhanced the hyperpolarizing-activated currents in LHb neurons. Bath application of Rp-cAMPs, a selective cAMP-PKA inhibitor, attenuated ACD-induced potentiation of EPSCs and IACD Finally, bath application of ZD7288, a selective blocker of hyperpolarization-activated cyclic nucleotide-gated channels, attenuated ACD-induced potentiation of firing, EPSCs, and IACD These results show that ACD exerts its aversive property by exciting LHb neurons via multiple cellular mechanisms, and new treatments targeting the LHb may be beneficial for alcoholism.SIGNIFICANCE STATEMENT Acetaldehyde (ACD) has been considered aversive peripherally and rewarding centrally. However, whether ACD has a central aversive property is unclear. Here, we report that ACD excites the lateral habenula (LHb), a brain region associated with aversion and negative valence, through multiple cellular and molecular mechanisms. Intra-LHb ACD produces significant conditioned place aversion. These results suggest that ACD's actions on the LHb neurons might contribute to its central aversive property and new treatments targeting the LHb may be beneficial for alcoholism.


Assuntos
Acetaldeído/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Habenula/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Dissulfiram/farmacologia , Antagonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Ácido Glutâmico/metabolismo , Habenula/fisiologia , Masculino , Neurônios/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Dopaminérgicos/metabolismo , Transmissão Sináptica/efeitos dos fármacos
16.
J Appl Microbiol ; 133(2): 400-409, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35384192

RESUMO

AIMS: Assessing the role of ramRsl , a gene absent in a lincomycin over-producing strain, in the regulation of morphological development and lincomycin biosynthesis in Streptomyces lincolnensis. METHODS AND RESULTS: The gene ramRsl was deleted from the wild-type strain NRRL 2936 and the ΔramR mutant strain was characterized by a slower growth rate and a delayed morphological differentiation compared to the original strain NRRL 2936. Furthermore, the ΔramR produced 2.6-fold more lincomycin than the original strain, and consistently the level of expression of all lincomycin cluster located genes was enhanced at 48 and 96 h in the ΔramR. Complementation of ΔramR with an intact copy of ramRsl restored all wild-type features, whereas the over-expression of ramRsl led to a reduction of 33% of the lincomycin yield. Furthermore, the level of expression of glnR, bldA and SLCG_2919, three of known lincomycin biosynthesis regulators, was lower in the ΔramR than in the original strain at the early stage of fermentation and we demonstrated, using electrophoretic mobility shift assay and XylE reporter assay, that glnR is a novel direct target of RamR. CONCLUSIONS: Altogether, these results indicated that, beyond promoting the morphological development, RamR regulates negatively lincomycin biosynthesis and positively the expression of the nitrogen regulator GlnR. SIGNIFICANCE AND IMPACT OF THE STUDY: We demonstrated that RamR plays a negative role in the regulation of lincomycin biosynthesis in S. lincolnensis. Interestingly, the deletion of this gene in other antibiotic-producing Streptomyces strains might also increase their antibiotic-producing abilities.


Assuntos
Regulação Bacteriana da Expressão Gênica , Streptomyces , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lincomicina/metabolismo , Streptomyces/genética , Streptomyces/metabolismo
17.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613829

RESUMO

Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) are prevalent neuropsychiatric disorders and frequently co-occur concomitantly. Individuals suffering from this dual diagnosis often exhibit increased symptom severity and poorer treatment outcomes than those with only one of these diseases. Lacking standard preclinical models limited the exploration of neurobiological mechanisms underlying PTSD and AUD comorbidity. In this review, we summarize well-accepted preclinical model paradigms and criteria for developing successful models of comorbidity. We also outline how PTSD and AUD affect each other bidirectionally in the nervous nuclei have been heatedly discussed recently. We hope to provide potential recommendations for future research.


Assuntos
Alcoolismo , Transtornos de Estresse Pós-Traumáticos , Animais , Alcoolismo/complicações , Alcoolismo/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Comorbidade , Ansiedade , Modelos Animais
18.
J Basic Microbiol ; 61(9): 772-781, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34313330

RESUMO

Lincomycin is an important antimicrobial agent which is widely used in clinical and animal husbandry. The biosynthetic pathway of lincomycin comes to light in the past 10 years, however, the regulatory mechanism is still unclear. In this study, a redox-sensing regulator Rex from Streptomyces lincolnensis (Rexlin ) was identified and characterized to affect cell growth and lincomycin biosynthesis. Disruption of rex resulted in an increase in cell growth, but a decrease in lincomycin production. The results of quantitative real-time polymerase chain reaction showed that Rexlin can promote transcription of the regulatory gene lmbU and the structural genes lmbA, lmbC, lmbJ, lmbV, and lmbW. However, electrophoretic mobility shift assay analysis demonstrated that Rexlin can not bind to the promoter regions of these genes above. Findings in this study broadened our horizons in the regulatory mechanism of lincomycin production and laid a foundation for strain improvement of antibiotic producers.


Assuntos
Antibacterianos/biossíntese , Vias Biossintéticas/genética , Regulação Bacteriana da Expressão Gênica , Lincomicina/biossíntese , Streptomyces/genética , Streptomyces/metabolismo , Proteínas de Bactérias/genética , Família Multigênica , Oxirredução , Fatores de Transcrição/genética
19.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202760

RESUMO

A phytochemical investigation of the leaves of the medicinal plant Isodon rubescens led to the isolation of the two new degraded abietane lactone diterpenoids rubesanolides F (1) and G (2). Their structures were elucidated based on the analyses of the HRESIMS and 1D/2D NMR spectral data, and their absolute configurations were determined by ECD spectrum calculations and X-ray single crystal diffraction methods. Compounds 1 and 2, with a unique γ-lactone subgroup between C-8 and C-20, were found to form a carbonyl carbon at C-13 by removal of the isopropyl group in an abietane diterpene skeleton. Rubesanolide G (2) is a rare case of abietane that possesses a cis-fused configuration between rings B and C. The two isolates were evaluated for their biological activities against two cancer cell lines (A549 and HL60), three fungal strains (Candida alba, Aspergillus niger and Rhizopus nigricans) and three bacterial strains (Escherichia coli, Staphylococcus aureus and Bacillus subtilis).


Assuntos
Abietanos , Anti-Infecciosos , Antineoplásicos Fitogênicos , Bactérias/crescimento & desenvolvimento , Fungos/crescimento & desenvolvimento , Isodon/química , Lactonas , Neoplasias/tratamento farmacológico , Folhas de Planta/química , Células A549 , Abietanos/química , Abietanos/isolamento & purificação , Abietanos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Células HL-60 , Humanos , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Neoplasias/metabolismo , Neoplasias/patologia
20.
Reproduction ; 159(3): 251-260, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31869309

RESUMO

Immune cells and cytokines have important roles in the pathogenesis of endometriosis. However, the production and role of cytokines of T helper type 1 (Th1) and Th2 cells in the progress of endometriosis have remained to be fully elucidated. The present study reported that the interferon (IFN)-γ levels and the percentage of IFN-γ+CD4+ cells were significantly increased in the peritoneal fluid (PF) at the early stage and maintained at a higher level at the advanced stage of endometriosis; furthermore, interleukin (IL)-10 and IL-10+CD4+ cells were elevated in the advanced stage of endometriosis. In addition, IL-2 levels in the PF at the advanced stage of endometriosis were elevated and negatively associated with IFN-γ expression. In a co-culture system of ectopic endometrial stromal cells (ESCs) and macrophages, elevated IL-2 was observed, and treatment with cytokines IL-2 and transforming growth factor-ß led to upregulation of the ratio of IL-2+ macrophages. IL-27-overexpressing ESCs and macrophages were able to induce a higher ratio of IL-10+CD4+ T cells. Blocking of IL-2 with anti-IL-2 neutralizing antibody led to upregulation of the ratio of IFN-γ+CD4+ T cells in the co-culture system in vitro. Recombinant human IL-10 and IFN-γ promoted the viability, invasiveness and transcription levels of matrix metalloproteinase (MMP)2, MMP9, and prostaglandin-endoperoxide synthase 2 of ESCs, particularly combined treatment with IL-10 and IFN-γ. These results suggest that IL-2 and IL-27 synergistically promote the growth and invasion of ESCs by modulating the balance of IFN-γ and IL-10 and contribute to the progress of endometriosis.


Assuntos
Endometriose/metabolismo , Interferon gama/metabolismo , Interleucinas/metabolismo , Linfócitos T/metabolismo , Adulto , Líquido Ascítico/metabolismo , Endometriose/imunologia , Feminino , Humanos , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Cultura Primária de Células , Células Estromais/fisiologia
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