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1.
Proc Natl Acad Sci U S A ; 120(16): e2217665120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37036971

RESUMO

The mitochondrial calcium uniporter is a Ca2+ channel that imports cytoplasmic Ca2+ into the mitochondrial matrix to regulate cell bioenergetics, intracellular Ca2+ signaling, and apoptosis. The uniporter contains the pore-forming MCU subunit, an auxiliary EMRE protein, and the regulatory MICU1/MICU2 subunits. Structural and biochemical studies have suggested that MICU1 gates MCU by blocking/unblocking the pore. However, mitoplast patch-clamp experiments argue that MICU1 does not block, but instead potentiates MCU via allosteric mechanisms. Here, we address this direct clash of the proposed MICU1 function. Supporting the MICU1-occlusion mechanism, patch-clamp demonstrates that purified MICU1 strongly suppresses MCU Ca2+ currents, and this inhibition is abolished by mutating the MCU-interacting K126 residue. Moreover, a membrane-depolarization assay shows that MICU1 prevents MCU-mediated Na+ flux into intact mitochondria under Ca2+-free conditions. Examining the observations underlying the potentiation model, we found that MICU1 occlusion was not detected in mitoplasts not because MICU1 cannot block, but because MICU1 dissociates from the uniporter complex. Furthermore, MICU1 depletion reduces uniporter transport not because MICU1 can potentiate MCU, but because EMRE is down-regulated. These results firmly establish the molecular mechanisms underlying the physiologically crucial process of uniporter regulation by MICU1.


Assuntos
Cálcio , Proteínas de Transporte da Membrana Mitocondrial , Cálcio/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Canais de Cálcio/metabolismo , Membranas Mitocondriais/metabolismo , Cálcio da Dieta , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo
2.
Appl Environ Microbiol ; 90(1): e0162523, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38168668

RESUMO

Many Acinetobacter species can grow on n-alkanes of varying lengths (≤C40). AlmA, a unique flavoprotein in these Acinetobacter strains, is the only enzyme proven to be required for the degradation of long-chain (LC) n-alkanes, including C32 and C36 alkanes. Although it is commonly presumed to be a terminal hydroxylase, its role in n-alkane degradation remains elusive. In this study, we conducted physiological, biochemical, and bioinformatics analyses of AlmA to determine its role in n-alkane degradation by Acinetobacter baylyi ADP1. Consistent with previous reports, gene deletion analysis showed that almA was vital for the degradation of LC n-alkanes (C26-C36). Additionally, enzymatic analysis revealed that AlmA catalyzed the conversion of aliphatic 2-ketones (C10-C16) to their corresponding esters, but it did not conduct n-alkane hydroxylation under the same conditions, thus suggesting that AlmA in strain ADP1 possesses Baeyer-Villiger monooxygenase (BVMO) activity. These results were further confirmed by bioinformatics analysis, which revealed that AlmA was closer to functionally identified BVMOs than to hydroxylases. Altogether, the results of our study suggest that LC n-alkane degradation by strain ADP1 possibly follows a novel subterminal oxidation pathway that is distinct from the terminal oxidation pathway followed for short-chain n-alkane degradation. Furthermore, our findings suggest that AlmA catalyzes the third reaction in the LC n-alkane degradation pathway.IMPORTANCEMany microbial studies on n-alkane degradation are focused on the genes involved in short-chain n-alkane (≤C16) degradation; however, reports on the genes involved in long-chain (LC) n-alkane (>C20) degradation are limited. Thus far, only AlmA has been reported to be involved in LC n-alkane degradation by Acinetobacter spp.; however, its role in the n-alkane degradation pathway remains elusive. In this study, we conducted a detailed characterization of AlmA in A. baylyi ADP1 and found that AlmA exhibits Baeyer-Villiger monooxygenase activity, thus indicating the presence of a novel LC n-alkane biodegradation mechanism in strain ADP1.


Assuntos
Acinetobacter , Oxigenases de Função Mista , Oxigenases de Função Mista/metabolismo , Alcanos/metabolismo , Oxirredução , Acinetobacter/genética
3.
Appl Environ Microbiol ; 90(3): e0224223, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38358247

RESUMO

The extensive accumulation of polyethylene terephthalate (PET) has become a critical environmental issue. PET hydrolases can break down PET into its building blocks. Recently, we identified a glacial PET hydrolase GlacPETase sharing less than 31% amino acid identity with any known PET hydrolases. In this study, the crystal structure of GlacPETase was determined at 1.8 Å resolution, revealing unique structural features including a distinctive N-terminal disulfide bond and a specific salt bridge network. Site-directed mutagenesis demonstrated that the disruption of the N-terminal disulfide bond did not reduce GlacPETase's thermostability or its catalytic activity on PET. However, mutations in the salt bridges resulted in changes in melting temperature ranging from -8°C to +2°C and the activity on PET ranging from 17.5% to 145.5% compared to the wild type. Molecular dynamics simulations revealed that these salt bridges stabilized the GlacPETase's structure by maintaining their surrounding structure. Phylogenetic analysis indicated that GlacPETase represented a distinct branch within PET hydrolases-like proteins, with the salt bridges and disulfide bonds in this branch being relatively conserved. This research contributed to the improvement of our comprehension of the structural mechanisms that dictate the thermostability of PET hydrolases, highlighting the diverse characteristics and adaptability observed within PET hydrolases.IMPORTANCEThe pervasive problem of polyethylene terephthalate (PET) pollution in various terrestrial and marine environments is widely acknowledged and continues to escalate. PET hydrolases, such as GlacPETase in this study, offered a solution for breaking down PET. Its unique origin and less than 31% identity with any known PET hydrolases have driven us to resolve its structure. Here, we report the correlation between its unique structure and biochemical properties, focusing on an N-terminal disulfide bond and specific salt bridges. Through site-directed mutagenesis experiments and molecular dynamics simulations, the roles of the N-terminal disulfide bond and salt bridges were elucidated in GlacPETase. This research enhanced our understanding of the role of salt bridges in the thermostability of PET hydrolases, providing a valuable reference for the future engineering of PET hydrolases.


Assuntos
Hidrolases , Polietilenotereftalatos , Polietilenotereftalatos/metabolismo , Filogenia , Estabilidade Enzimática , Hidrolases/metabolismo , Dissulfetos , Temperatura
4.
Cancer Invest ; 42(6): 527-537, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38965994

RESUMO

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Neoplasias Retais/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Idoso , Quimioembolização Terapêutica/métodos , Prognóstico , Resultado do Tratamento , Adulto , Quimiorradioterapia/métodos
5.
J Oral Pathol Med ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866540

RESUMO

BACKGROUND: Oral lichen planus (OLP) is a common T cell-mediated oral mucosal immune inflammatory disease. Intraepithelial lymphocytes (IELs) are a unique subset of T cells that play an important role in regulating immune response. This study aims to investigate the phenotype and the differentiation mechanism of IELs in OLP. METHODS: The expression of CD4, CD8α, CD8ß, T-helper-inducing POZ/Krueppel-like factor (ThPOK), and RUNX family transcription factor 3 (Runx3) in the epithelium and peripheral blood mononuclear cells (PBMCs) of OLP was determined by immunofluorescence and immunohistochemistry. Then, the correlations among them were analyzed. Naïve CD4+ T cells were sorted from blood of OLP patients and stimulated with retinoic acid (RA) and transforming growth factor-ß1 (TGF-ß1). Then the expression of CD4, CD8α, CD8ß, ThPOK, and Runx3 was investigated by immunocytochemistry. RESULTS: CD8α expression and CD8αα+ cells were upregulated in the epithelium of OLP, whereas they were downregulated in PBMCs of OLP. CD8ß was not expressed in the epithelium of OLP. CD4, CD8α, and Runx3 expression and CD4+CD8α+ cells were increased, whereas ThPOK expression was decreased in the epithelium of OLP. CD8α expression was positively correlated with Runx3 expression, whereas ThPOK expression was negatively correlated with Runx3 expression. After RA and TGF-ß1 stimulation, CD8α and Runx3 expression was upregulated, and ThPOK expression was downregulated in naïve CD4+ T cells. CONCLUSION: CD4+CD8αα+ IELs may be the dominant phenotype of IELs in OLP, and the differentiation of CD4+CD8αα+ IELs in OLP is negatively regulated by ThPOK and positively regulated by Runx3.

6.
Mol Ther ; 31(6): 1705-1721, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35974702

RESUMO

Circular RNAs (circRNAs) are a novel class of endogenous RNAs with a covalently closed loop structure. Many circRNAs have been found to participate in cancer progression. However, the detailed generation process, functions, and related mechanisms of circRNAs in prostate cancer (PCa) remain largely unknown. In the present study, we identified circEXOC6B, a novel suppressor in the metastasis of PCa. Functionally, circEXOC6B, originating from the exocyst complex component 6B (EXOC6B) gene, inhibited migration and invasion of PCa in vitro and in vivo. Mechanistically, by acting as a protein scaffold, circEXOC6B enhanced the binding of human RNA binding motif single strand interacting protein 1 (RBMS1) and human antigen R (HuR) and further increased A-kinase anchoring protein 12 (AKAP12) expression to inhibit PCa metastasis. Unlike previous studies, we found that one pair of short inverted repeats in flanking introns at least partly promoted the circularization of circEXOC6B. Our study presents a novel mechanism for the inhibitory role of circEXOC6B in PCa metastasis and provides new insight into the molecular process of circRNA generation.


Assuntos
Neoplasias dos Genitais Femininos , MicroRNAs , Neoplasias da Próstata , Masculino , Feminino , Humanos , RNA Circular/genética , RNA/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Ecotoxicol Environ Saf ; 279: 116453, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772139

RESUMO

Chlorinated polyfluorinated ether sulfonate, commercially known as F-53B, has been associated with adverse birth outcomes. However, the reproductive toxicology of F-53B on the placenta remains poorly understood. To address this gap, we examined the impact of F-53B on placental injury and its underlying molecular mechanisms in vivo. Pregnant C57BL/6 J female mice were randomly allocated to three groups: the control group, F-53B 0.8 µg/kg/day group, and F-53B 8 µg/kg/day group. After F-53B exposure through free drinking water from gestational day (GD) 0.5-14.5, the F-53B 8 µg/kg/day group exhibited significant increases in placental weights and distinctive histopathological alterations, including inflammatory cell infiltration, heightened syncytiotrophoblast knots, and a loosened trophoblastic basement membrane. Within the F-53B 8 µg/kg/day group, placental tissue exhibited increased apoptosis, as indicated by increased caspase3 activation. Furthermore, F-53B potentially induced the NF-κB signaling pathway activation through IκB-α phosphorylation. Subsequently, this activation upregulated the expression of inflammatory cytokines and components of the NLRP3 inflammasome, including activated caspase1, IL-1ß, IL-18, and cleaved gasdermin D (GSDMD), ultimately leading to pyroptosis in the mouse placenta. Our findings reveal a pronounced inflammatory injury in the placenta due to F-53B exposure, suggesting potential reproductive toxicity at concentrations relevant to the human population. Further toxicological and epidemiological investigations are warranted to conclusively assess the reproductive health risks posed by F-53B.


Assuntos
Inflamassomos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR , Placenta , Animais , Feminino , Gravidez , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Placenta/efeitos dos fármacos , Placenta/patologia , Camundongos , Inflamassomos/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/patologia , Apoptose/efeitos dos fármacos , NF-kappa B/metabolismo , Fluorocarbonos/toxicidade , Transdução de Sinais/efeitos dos fármacos
8.
Chem Biodivers ; 21(5): e202400283, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38485665

RESUMO

Fifteen bibenyls and four fluorenones, including five new bibenzyl-phenylpropane hybrids, were isolated from the aerial part of Dendrobium nobile Lindl. Their structures were determined by spectroscopic methods. Bioassay on the LPS-induced proliferations of mouse splenic B lymphocytes, and Con A-induced T lymphocytes showed that compounds 1, 2, and 14 showed excellent immunosuppressive activities with IC50 values of 1.23, 1.01, and 3.87 µM, respectively, while compounds 3-4, 7, 10, 13, and 15 exhibited moderate immunosuppressive activities with IC50 values ranging from 6.89 to 14.2 µM.


Assuntos
Bibenzilas , Proliferação de Células , Dendrobium , Imunossupressores , Dendrobium/química , Animais , Camundongos , Imunossupressores/farmacologia , Imunossupressores/química , Imunossupressores/isolamento & purificação , Bibenzilas/química , Bibenzilas/farmacologia , Bibenzilas/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Relação Dose-Resposta a Droga , Concanavalina A/antagonistas & inibidores , Concanavalina A/farmacologia
9.
Aquac Nutr ; 2024: 3147505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374819

RESUMO

This study developed a recombinant Bacillus subtilis to carry the LGSPDVIVIR peptide (cmP4) isolated from the hydrolyzed products of cottonseed meal with excellent antioxidant and immune-enhancing properties in vitro. It was carried as a tandem of five cmP4 peptides (cmP4') to be stably expressed on a large scale. Then, its effectiveness was evaluated in Chinese mitten crab (Eriocheir sinensis) based on growth performance, redox defense, and innate immunity. A total of 280 crabs (mean body weight: 41.40 ± 0.14) were randomly assigned to seven diets including a control one (without B. subtilis) and six experimental ones with different doses (107,108, and 109 CFU/kg) of unmodified and recombinant B. subtilis, respectively, for 12 weeks. Each diet was tested in four tanks of crabs (10/tank). In terms of bacterial dosages, the final weight (FW), weight gain (WG), hemolymph and hepatopancreatic activities of superoxide dismutase (SOD), catalase (CAT), lysosome (LZM), acid phosphatase (ACP) and alkaline phosphatase (AKP), and hepatopancreatic transcriptions of cat, mitochondrial manganese superoxide dismutase (mtmnsod), thioredoxin-1 (trx1), and prophenoloxidase (propo) all increased significantly with increasing B. subtilis dosages, while hemolymph and hepatopancreatic malondialdehyde (MDA) content and the transcriptions of toll like receptors (tlrs), NF-κB-like transcription factor (relish), and lipopolysaccharide-induced TNF-α factor (litaf) all decreased remarkably. In terms of bacterial species, the recombinant B. subtilis group obtained significantly high values of FW, WG, hemolymph, and hepatopancreatic activities of SOD, CAT, LZM, ACP, and AKP, and the transcriptions of mtmnsod, peroxiredoxin 6 (prx6), and propo compared with the unmodified B. subtilis, while opposite results were noted in hemolymph and hepatopancreatic MDA content and the transcriptions of tlrs, relish, and litaf. These results indicated that dietary supplementation with 109 CFU/kg of recombinant B. subtilis can improve the growth performance, redox defense, and nonspecific immunity of E. sinensis.

10.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3473-3483, 2024 Jul.
Artigo em Zh | MEDLINE | ID: mdl-39041119

RESUMO

Panax ginseng is a perennial herb with the main active compounds of ginsenosides. Among the reported ginsenosides, ginsenoside Rg_1 not only has a wide range of medicinal functions and abundant content but also is one of the major ginsenoside for the quality evaluation of this herb in the Chinese Pharmacopoeia. The main biosynthesis pathway of ginsenoside Rg_1 in P. ginseng has been clarified, which lays a foundation for the comprehensive and in-depth analysis of the biosynthesis and regulatory mechanism of ginseno-side Rg_1. However, the biosynthesis of ginsenoside Rg_1 is associated with other complex processes involving a variety of regulatory genes and catalyzing enzyme genes, which remain to be studied comprehensively. With the transcriptome data of 344 root samples from 4-year-old P. ginseng plants and their corresponding ginsenoside Rg_1 content obtained in the previous study, this study screened out 217 differentially expressed genes(DEGs) with Rg_1 content changes by DEseq2 analysis in R language. Furthermore, the weighted gene co-expression network analysis(WGCNA) revealed 40 hub genes among the DEGs.Pearsoncorrelation analysis was further perforned to yield 20 candidate genes significantly correlated with ginsenoside Rg_1 content, and these genes were annotated to multiple metabolic processes including primary metabolism and secondary metabolism. Finally, the treatment of P. ginseng adventitious roots with methyl jasmonate indicated that 16 of these genes promoted the biosynthesis of ginsenoside Rg_1 in response to methyl jasmonate induction. Finally, one of the 16 genes was randomly selected to verify the function of the gene by genetic transformation and qRT-PCR and to confirm the rationality of the methodology of this study. The above results lay a foundation for studying the mechanism for regulation on the synthesis of ginsenoside Rg_1 and provide genetic resources for the industrial production of ginsenoside Rg_1.


Assuntos
Regulação da Expressão Gênica de Plantas , Ginsenosídeos , Panax , Ginsenosídeos/biossíntese , Panax/genética , Panax/metabolismo , Panax/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica
11.
Angew Chem Int Ed Engl ; : e202406557, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38798154

RESUMO

The surge in lithium-ion batteries has heightened concerns regarding metal resource depletion and the environmental impact of spent batteries. Battery recycling has become paramount globally, but conventional techniques, while effective at extracting transition metals like cobalt and nickel from cathodes, often overlook widely used spent LiFePO4 due to its abundant and low-cost iron content. Direct regeneration, a promising approach for restoring deteriorated cathodes, is hindered by practicality and cost issues despite successful methods like solid-state sintering. Hence, a smart prelithiation separator based on surface-engineered sacrificial lithium agents is proposed. Benefiting from the synergistic anionic and cationic redox, the prelithiation separator can intelligently release or intake active lithium via voltage regulation. The staged lithium replenishment strategy was implemented, successfully restoring spent LiFePO4's capacity to 163.7 mAh g-1 and a doubled life. Simultaneously, the separator can absorb excess active lithium up to approximately 600 mAh g-1 below 2.5 V to prevent over-lithiation of the cathode This innovative, straightforward, and cost-effective strategy paves the way for the direct regeneration of spent batteries, expanding the possibilities in the realm of lithium-ion battery recycling.

12.
J Biol Chem ; 298(5): 101818, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35278432

RESUMO

Gonadal white adipose tissue (gWAT) can regulate gametogenesis via modulation of neuroendocrine signaling. However, the effect of gWAT on the local microenvironment of the gonad was largely unknown. Herein, we ruled out that gWAT had a neuroendocrine effect on gonad function through a unilateral lipectomy strategy, in which cutting off epididymal white adipose tissue could reduce seminiferous tubule thickness and decrease sperm counts only in the adjacent testis and epididymis of the affected gonad. Consistent with the results in males, in females, ovary mass was similarly decreased by lipectomy. We determined that the defects in spermatogenesis were mainly caused by augmented apoptosis and decreased proliferation of germ cells. Transcriptome analysis suggested that lipectomy could disrupt immune privilege and activate immune responses in both the testis and ovary on the side of the lipectomy. In addition, lipidomics analysis in the testis showed that the levels of lipid metabolites such as free carnitine were elevated, whereas the levels of glycerophospholipids such as phosphatidylcholines and phosphatidylethanolamines were decreased, which indicated that the metabolic niche was also altered. Finally, we show that supplementation of phosphatidylcholine and phosphatidylethanolamine could partially rescue the observed phenotype. Collectively, our findings suggest that gWAT is important for gonad function by not only affecting whole-body homeostasis but also via maintaining local metabolic and immune niches.


Assuntos
Tecido Adiposo Branco , Gônadas , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Epididimo , Feminino , Masculino , Camundongos , Espermatogênese , Testículo/metabolismo
13.
Environ Microbiol ; 25(12): 2822-2833, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775503

RESUMO

Polyethylene terephthalate (PET) is a major component of microplastic contamination globally, which is now detected in pristine environments including Polar and mountain glaciers. As a carbon-rich molecule, PET could be a carbon source for microorganisms dwelling in glacier habitats. Thus, glacial microorganisms may be potential PET degraders with novel PET hydrolases. Here, we obtained 414 putative PET hydrolase sequences by searching a global glacier metagenome dataset. Metagenomes from the Alps and Tibetan glaciers exhibited a higher relative abundance of putative PET hydrolases than those from the Arctic and Antarctic. Twelve putative PET hydrolase sequences were cloned and expressed, with one sequence (designated as GlacPETase) proven to degrade amorphous PET film with a similar performance as IsPETase, but with a higher thermostability. GlacPETase exhibited only 30% sequence identity to known active PET hydrolases with a novel disulphide bridge location and, therefore may represent a novel PET hydrolases class. The present work suggests that extreme carbon-poor environments may harbour a diverse range of known and novel PET hydrolases for carbon acquisition as an environmental adaptation mechanism.


Assuntos
Hidrolases , Polietilenotereftalatos , Polietilenotereftalatos/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Camada de Gelo , Plásticos , Carbono
14.
Mol Reprod Dev ; 90(10-11): 774-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733694

RESUMO

Male fertility declines with age. The mevalonate pathway, through which cholesterol and nonsteroidal isoprenoids are synthesized, plays key role in metabolic processes and is an essential pathway for cholesterol production and protein prenylation. Male reproductive aging is accompanied by dramatic changes in the metabolic microenvironment of the testis. Since the mevalonate pathway has an important role in spermatogenesis, we attempted to explore the association between male reproductive aging and the mevalonate pathway to explain the mechanism of male reproductive aging. Alterations in the mevalonate pathway may affect male reproductive aging by decreasing cholesterol synthesis and altering testis protein prenylation. Decreased cholesterol levels affect cholesterol modification, testosterone production, and remodeling of germ cell membranes. Aging-related metabolic disorders also affect the metabolic coupling between somatic cells and spermatogenic cells, leading to male fertility decline. Therefore, we hypothesized that alterations in the mevalonate pathway represent one of the metabolic causes of reproductive aging.


Assuntos
Colesterol , Ácido Mevalônico , Masculino , Humanos , Ácido Mevalônico/metabolismo , Colesterol/metabolismo , Reprodução , Testículo/metabolismo
15.
Bioorg Chem ; 134: 106438, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36848715

RESUMO

Horsfiequinone G (1), a dimeric diarylpropane featuring an unprecedentedly oxo-6/7/6 fused ring system, a new flavane, horsfielenide F (2), three naturally occurring spirocyclic monomers containing all-carbon quaternary centers, horspirotone A (3), horspirotone B (4), and methyl spirobroussonin B (5), along with horsfiequinone A (6) were isolated from Horsfieldia kingii. Their structures and absolute configurations were determined by the inspection of extensive spectroscopic data and electronic circular dichroism (ECD) calculations. Biological evaluations of these isolates revealed that compounds 1 - 3 and 5 - 6 exhibited specifically immunosuppressive activities against Con A-induced T lymphocytes with IC50 values ranging from 2.07 to 12.34 µM (selectivity indices = 2.3-25.2). Compound 1 also suppressed the secretion of inflammatory factors like IL-1ß and IL-6 in RAW264.7 cells which could present a new class of nonsteroidal anti-inflammatory agent. Finally, the primary structure-activity relationship (SAR) was also discussed.


Assuntos
Anti-Inflamatórios não Esteroides , Imunossupressores , Anti-Inflamatórios não Esteroides/farmacologia , Carbono , Dicroísmo Circular , Imunossupressores/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade
16.
Chem Biodivers ; 20(3): e202201075, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36762483

RESUMO

A new phenylpropanoid, myristriol (1), along with 11 known ones were isolated from the seed kernel of Myristica fragrans Houtt. Their chemical structures were clearly elucidated by extensive spectroscopic analysis. In which, the relative configuration of 1 was finally determined as erythro-1 by comparison the NMR data of two synthetic erythro- and threo-diastereoisomers with that of natural 1.


Assuntos
Myristica , Fenilpropionatos , Espectroscopia de Ressonância Magnética , Myristica/química , Sementes/química , Fenilpropionatos/química
17.
Chem Biodivers ; 20(12): e202301600, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37963833

RESUMO

Four previously undescribed diastereomeric lignan glycosides, namely cistadesertosides B-E (1-4) were isolated from the stems of cultural Cistanche deserticola in Tarim desert. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses, including IR, HR-ESI-MS, 1D and 2D NMR, circular dichroism (CD) data and chemical degradation. The in vitro anti-inflammatory activity of the isolates was also investigated. It showed that compounds 3 and 4 exhibited potential effects with IC50 values of 21.17 µM and 26.97 µM, respectively (positive control quercetin, IC50 , 10.01 µM).


Assuntos
Cistanche , Lignanas , Glicosídeos/farmacologia , Glicosídeos/química , Lignanas/farmacologia , Lignanas/química , Cistanche/química , Extratos Vegetais/química , Anti-Inflamatórios
18.
Molecules ; 28(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38067625

RESUMO

MOF (metal organic framework) materials have been used as functional materials in a number of fields due to their diverse spatial tunability, which produces rich porous structures with stable and continuous pores and a high specific surface area. A triboelectric nanogenerator can convert trace mechanical energy into electrical energy, and the application of MOF materials to triboelectric nanogenerators has been intensively studied. In this work, we report on two MOFs with similar spatial structures, and the modulation of the end microstructures was achieved using the difference in F content. The output performance of friction power generation increases with the increase in F content, and the obtained polyacidic ligand materials can be used to construct self-powered corrosion protection systems, which can effectively protect metallic materials from corrosion.

19.
Aquac Nutr ; 2023: 8347921, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415969

RESUMO

Growth retardation and prolonged marketing cycle have been noticed in the practical aquaculture of Chinese mitten crab (Eriocheir sinensis) fed with artificial feed. Plant protein hydrolysates contain a large number of small peptides and free amino acids, which can improve the growth performance of aquatic animals. However, the potential mechanisms are still not well elucidated. In this research, the influences of cottonseed meal protein hydrolysate (CPH) on the growth, feed utilization, muscle growth, and molting performance were investigated in E. sinensis. A total of 240 crabs (mean body weight 37.32 ± 0.38 g) were individually randomly distributed to six diets supplemented with 0%, 0.2%, 0.4%, 0.8%, 1.6%, and 3.2% of CPH for 12 weeks. These findings indicated that the addition of CPH at 0.4% significantly increased the survival rate, body protein gain, apparent protein utilization, trypsin and pepsin activities, and the methyl farnesoate content. When the dose reached 0.8%, the weight growth ratio, meat yield, ecdysone concentration, and the transcription of the ecdysteroid receptor all significantly increased, while the transcriptions of both myostatin and molt-inhibiting hormone significantly decreased. When CPH was added at 1.6%-3.2%, the feed conversion ratio, body crude protein content, Na+/K+-ATPase activity, and the molting ratio were all significantly improved, while the opposite was true for the transcription of the transforming growth factor-ß type I receptor. The investigation results indicated that when added above 0.4%, CPH could stimulate the growth performance of E. sinensis and promote the muscle growth and molting performance.

20.
Yi Chuan ; 45(6): 488-500, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340963

RESUMO

Left-right asymmetry is an essential feature in bilateral animals. The mechanism underlying the left-right asymmetrical organ morphogenesis is a central question in developmental biology. Studies in vertebrates show that left-right asymmetry formation needs three essential steps: the initial left-right symmetry breaking, the left-right asymmetrical gene expression, and the left-right asymmetrical organ morphogenesis. Many vertebrates use cilia to produce directional fluid flow to break symmetry during embryonic development, asymmetric Nodal-Pitx2 signaling to pattern the left-right asymmetry, and Pitx2 and other genes to control the morphogenesis of asymmetrical organs. In invertebrates, there are left-right mechanisms independent of cilia and even others more different from that of vertebrates. In this review, we summarize the major steps and relevant molecular mechanisms of left-right asymmetric development in vertebrates and invertebrates, aiming to provide a reference for the understanding of the origin and evolution of the left-right developmental mechanism.


Assuntos
Padronização Corporal , Vertebrados , Animais , Padronização Corporal/genética , Vertebrados/genética , Morfogênese/genética , Desenvolvimento Embrionário/genética , Cílios , Regulação da Expressão Gênica no Desenvolvimento
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