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1.
Eur J Med Res ; 26(1): 105, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526113

RESUMO

BACKGROUND: Platelet-rich plasma (PRP) has the potential to be used for bone regeneration. However, its effect on osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) and its effect on cell autophagy of hPDLSCs remain unknown. In this study, we investigated the effects of PRP on cell viability and osteogenic differentiation of hPDLSCs and the underlying molecular mechanisms. METHODS: hPDLSCs were isolated and identified by morphology and flow cytometry analysis. Next, thrombin-activated PRP was used to stimulate hPDLSCs. The MTT assay was used to analyze cell viability. Osteogenic differentiation was investigated using alkaline phosphatase (ALP) activity assay, alizarin red S (ARS) staining, and gene expression analysis of osteogenic markers. Expression of the autophagic proteins was determined using western blotting. RESULTS: Thrombin-activated PRP significantly enhanced cell viability, ALP activity, osteogenic-related mRNA levels and alizarin red-mineralization activity in hPDLSCs in a dose-dependent manner. Furthermore, activated PRP dose-dependently increased LC3-II/I ratio and the expression of SIRT1 and Beclin-1. PRP treatment also enhanced the autophagic flux. It was also demonstrated that the inhibition of SIRT1 using sirtinol or suppression of autophagy by 3-methyladenine (3-MA) abrogated PRP-induced viability and osteogenic differentiation of hPDLSCs. CONCLUSION: Our study suggested that thrombin-activated PRP accelerated the viability and osteogenic differentiation of hPDLSCs via SIRT1-mediated autophagy induction.

2.
FASEB J ; 35(9): e21332, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34423867

RESUMO

Emerging research has highlighted the capacity of microRNA-23a-3p (miR-23a-3p) to alleviate inflammatory pain. However, the molecular mechanism by which miR-23a-3p attenuates inflammatory pain is yet to be fully understood. Hence, the current study aimed to elucidate the mechanism by which miR-23a-3p influences inflammatory pain. Bioinformatics was initially performed to predict the inflammatory pain related downstream targets of miR-23a-3p in macrophage-derived extracellular vesicles (EVs). An animal inflammatory pain model was established using Complete Freund's Adjuvant (CFA). The miR-23a-3p expression was downregulated in the microglia of CFA-induced mice, after which the inflammatory factors were determined by ELISA. FISH and immunofluorescence were performed to analyze the co-localization of miR-23a-3p and microglia. Interestingly, miR-23a-3p was transported to the microglia via M2 macrophage-EVs, which elevated the mechanical allodynia and the thermal hyperalgesia thresholds in mice model. The miR-23a-3p downstream target, USP5, was found to stabilize HDAC2 via deubiquitination to promote its expression while inhibiting the expression of NRF2. Taken together, the key findings of the current study demonstrate that macrophage-derived EVs containing miR-23a-3p regulates the HDAC2/NRF2 axis by decreasing USP5 expression to alleviate inflammatory pain, which may provide novel therapeutic targets for the treatment of inflammatory pain.


Assuntos
Vesículas Extracelulares/metabolismo , Histona Desacetilase 2/metabolismo , Inflamação/metabolismo , Macrófagos/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Dor/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Linhagem Celular , Enzimas Desubiquitinantes/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Estabilidade Enzimática , Vesículas Extracelulares/genética , Inflamação/genética , Inflamação/terapia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/metabolismo , Modelos Biológicos , Dor/genética , Manejo da Dor , Proteases Específicas de Ubiquitina/genética , Ubiquitinação
3.
Plant Sci ; 309: 110948, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34134847

RESUMO

WRKY transcription factors belong to a superfamily that is involved in many important biological processes, including plant development and senescence. However, little is known about the transcriptional regulation mechanisms of WRKY genes involved in kiwifruit postharvest ripening. Here, we isolated a WRKY gene from the kiwifruit genome and named it AcWRKY40. AcWRKY40 is a nucleus-localized protein that possesses transcriptional activation activity. The expression of AcWRKY40 was detected, and the gene responded to ethylene treatment during kiwifruit postharvest ripening, indicating its involvement in this process at the transcriptional level. We found multiple cis-acting elements related to maturation and senescence in the AcWRKY40 promoter. GUS activity analysis showed that its promoter activity was induced by exogenous ethylene. Yeast one-hybrid and dual-luciferase assays demonstrated that AcWRKY40 binds to the promoters of AcSAM2, AcACS1, and AcACS2 to activate them. In addition, transient transformations showed that AcWRKY40 enhances the expression of AcSAM2, AcACS1, and AcACS2. Taken together, these results suggest that AcWRKY40 is involved in kiwifruit postharvest ripening, possibly by regulating the expression of genes related to ethylene biosynthesis, thus deepening our understanding of the regulatory mechanisms of WRKY transcription factors in fruit ripening.


Assuntos
Actinidia/genética , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Transcriptoma , Actinidia/metabolismo , Frutas/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Org Lett ; 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34096735

RESUMO

Unprecedented copper-catalyzed regiodivergent hydrosilylation reactions of substituted 1,3-dienes with hydrosilanes have been developed. The 1,2- and 1,4-hydrosilylations of 1-(hetero)aryl-substituted 1,3-dienes were highly selectively controlled via variation of the catalytic systems. Meanwhile, the 1,4-hydrosilylation reaction of 2-aryl-substituted 1,3-dienes with diphenylsilane was also successfully realized for the first time. These methods provide convenient and efficient approaches for the synthesis of structurally diverse allylsilanes.

5.
Org Lett ; 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33970651

RESUMO

In this protocol, copper-catalyzed diverse silylative carbocyclization reactions of 2,2'-diethynylbiaryl derivatives with silaboronate were reported. Three new and novel types of domino reactions for the copper-catalyzed transformation of silaboronate were discovered. The corresponding cyclobuta[l]phenanthrene, bis((silyl)methyl)phenanthrene, and silyl-substituted exocyclic diene products were chemoselectively formed with high efficiency.

6.
Med Sci Monit ; 27: e928480, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33931577

RESUMO

BACKGROUND Acute myocardial infarction is the leading cause of mortality among adults worldwide. The present study aimed to investigate the role and mechanism of thrombin and SIRT1 in hypoxia/reoxygenation (H/R) injury. MATERIAL AND METHODS H9c2 cardiomyocytes were used to create an H/R model to simulate in vivo ischemia/reperfusion injury. The MTT assay was used to measure cell viability, qRT-PCR was used to detect the level of SIRT1, thrombin, and PAR-1, and western blot analysis was conducted for evaluation of thrombin, PAR-1, SIRT1, LC3I, LC3II, and Beclin1. ELISA was applied for determination of IL-1ß, IL-6, TNF-alpha, MMP-9, and ICAM-1. After the establishment of the H/R model, superoxide dismutase (SOD) activity was evaluated by the xanthine oxidase method, malondialdehyde content was detected by thiobarbituric acid assay, and reactive oxygen species generation was measured by CM-H2DCFDA. RESULTS The findings showed that thrombin enhanced inflammatory factor secretion and oxidative stress but inhibited cell viability in H/R-injured cardiomyocytes. We also observed that thrombin promoted autophagy in H/R-injured cardiomyocytes. In addition, thrombin enhanced the upregulation of SIRT1 expression by H/R. However, it was found that inhibition of SIRT1 could suppress the effect of thrombin on inflammatory factor secretion, oxidative stress, and cell viability. Moreover, downregulation of SIRT1 suppressed the inhibitory effect of thrombin on autophagy in H/R injury. CONCLUSIONS Thrombin aggravates H/R injury of cardiomyocytes by activating an autophagy pathway mediated by SIRT1. These findings might provide a potential target therapy for the treatment of ischemia/reperfusion injury in future clinical work.


Assuntos
Autofagia/fisiologia , Hipóxia/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Transdução de Sinais/fisiologia , Sirtuína 1/metabolismo , Trombina/metabolismo , Animais , Apoptose/fisiologia , Sobrevivência Celular/fisiologia , Regulação para Baixo/fisiologia , Inflamação/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Regulação para Cima/fisiologia
7.
Org Lett ; 23(5): 1898-1903, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33624501

RESUMO

In this protocol, the chemoselective defluoromethoxylation reactions of 2-trifluoromethyl-1,3-enynes were developed. The enynic and allenic orthoesters were selectively produced in good to excellent yields via multiple substitution processes under mild reaction conditions, respectively. The enynic orthoester products were proved capable of acting as efficient "platform molecules" to access various functionalized allenyl compounds.

8.
Kaohsiung J Med Sci ; 37(1): 38-46, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32841515

RESUMO

Osteogenesis induced by mechanical stretch is the main factor affecting the orthodontic treatment. Due to the masticatory force transmitted by tooth, human periodontal ligament fibroblasts (hPDLFs) could enhance osteogenic differentiation, and remolding of periodontal. Therefore, in-depth study of hPDLFs osteogenic differentiation and its regulatory mechanism is helpful in the understanding of periodontal remolding promoted by orthodontic force. In the present study, 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide showed that miR-140 inhibited the viability of hPDLFs cells. Moreover, we provided evidence that miR-140 inhibited alkaline phosphatase (ALP) activity, Alizarin Red S (ARS) activity and the mRNA expression of osteogenesis associated genes, including ALP, runt-related transcription factor 2, collagen 1, and osteocalcin. Besides, double-luciferase reporter result demonstrated that Ras homolog gene family, member A (RhoA) was a downstream target gene of miR-140, and by inhibiting RhoA-transcriptional co-activator with PDZ-binding motif (TAZ) signaling pathway, miR-140 suppressed the osteogenesis differentiation of hPDLFs. Furthermore, overexpression of RhoA or TAZ promoted ALP activity, ARS activity and osteogenesis associated genes expression, which was inhibited by miR-140 mimics. Our findings not only provided a possible mechanism of hPDLFs osteogenic differentiation but also proposed the clinical application of miR-140 inhibitor to target RhoA-TAZ for orthodontic treatment.

9.
Org Lett ; 22(19): 7735-7742, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32966085

RESUMO

A copper-catalyzed anti-Markovnikov hydrosilylation of alkynes with PhSiH3 was reported. This reaction represents a notable and efficient example on copper-catalyzed hydrosilylatioin of alkynes, which shows excellent recognition between the terminal and internal triple bonds. Various (hetero)aromatic and aliphatic substituted terminal alkynes underwent this reaction to afford the (E)-vinylsilanes in high yields and with excellent regioselectivity.

10.
Org Lett ; 22(4): 1360-1367, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32013456

RESUMO

The Cu-catalyzed 1,4-protosilylation and protoborylation of trifluoromethyl-substituted conjugated enynes were developed to access functionalized homoallenylsilanes and homoallenylboronates. This protocol also provides a general method to synthesize optically active homoallenylsilanes and homoallenylboronates in moderate to excellent yields with high enantiomeric excess by using new designed chiral bisoxazoline ligands. Simultaneously, the transformations of homoallenylsilanes and homoallenylboronates were also explored to synthesize useful building blocks.

11.
Org Lett ; 22(4): 1326-1330, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31999462

RESUMO

A novel method of metal-free dehydrogenative silylation of enamides has been developed. The desired functionalized vinylsilane products were obtained in moderate to good yield and with high stereoselectivities. This protocol displays good tolerance of various functionalities. Furthermore, the high chemoselectivity of this reaction enables us to introduce different unsaturated C-C moieties to the products. The ease of further derivatization of the products to other useful compounds also demonstrates the highly synthetic utility of the current methodology.

12.
Angew Chem Int Ed Engl ; 58(46): 16538-16542, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31532868

RESUMO

A copper-catalyzed silylation of propargyl dichlorides was developed to access chloro-substituted allenylsilanes under mild reaction conditions. Moreover, enantioenriched chloro-substituted allenylsilanes can be synthesized in moderate to high yields and good enantioselectivities with this protocol.

13.
Front Physiol ; 10: 937, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31404251

RESUMO

Lactobacillus paracasei subsp. paracasei L1 was previously isolated from sweet potato sour liquid. This bacterial species specifically binds onto starch granular surfaces, triggering the enzymatic hydrolysis of raw starch. We investigated the functional and safety properties of strain L1 in vitro to establish its probiotic potential, and analyzed its effect on growth performance and intestinal microflora of chicken in feeding experiments. The optimal growth conditions of strain L1 included low pH and high concentrations of bile salts and NaCl. Its 1-, 2-, and 24-h autoaggregation values were 15.8 ± 1.2%, 20.4 ± 2.3%, and 47.2 ± 0.8%, respectively, with the surface hydrophobicity value at 560 nm of 38.1 ± 2.7%. Further, its adhesion rate to Caco-2 cells was 22.37 ± 1.44%. Strain L1 was resistant to erythromycin and azithromycin, but sensitive to other antibiotics tested. For the feeding experiments, 240 chickens with similar weights were randomly divided into a control (C) group and strain L1 (L) group and fed for 8 weeks. Strain L1 promoted the weight gain of chickens in L group. A significant increase in the population size of the two phyla and 23 genera in the small intestine was observed in the presence of strain L1 (P < 0.05), with 0 phyla and 4 genera showing significant increase in the cecum (P < 0.05). In the small intestine, the abundance of six functional genes at Kyoto Encyclopedia of Genes and Genomes (KEGG) level 2 and 49 genes at KEGG level 3 was significantly increased in group L (P < 0.05), with lesser changes noted in the cecum. An increase in the metabolic pathway functions, including enzyme families and the digestive system, was observed in the intestinal microbiota in the L group compared to the C group. However, the other metabolic pathway functions, including metabolism of fatty acid biosynthesis, as well as metabolism of glycerolipids and propanoate, increased in the cecal microbiota of the L group relative to the C group. These changes are most likely related to the changes in the gut microbiota composition. Collectively, strain L1 supplementation may promote growth performance and improve the intestinal microflora in chicken although further studies are needed to confirm this.

14.
J Org Chem ; 84(20): 12848-12855, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31414808

RESUMO

A Pd(II)-catalyzed mild and highly regioselective 6-endo cyclization/alkylation reaction of o-(alkynyl)styrenes with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert a C-C double bond of allylic alcohol through a cross-coupling reaction and led to the formation of (alkyl)naphthalenes. This cascade cross-coupling reaction represents a direct and atom economic method for the construction of functionalized naphthalene derivatives in moderate to good yields.

15.
Org Lett ; 21(15): 6016-6020, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31318220

RESUMO

A copper-catalyzed highly regio- and stereoselective silaboration of alkynes was developed. In this work, direct cis-difunctionalization of alkynes was realized with silaboronate reagent and copper catalyst in aprotic solvents. The regiodivergent silaborations were controlled by tuning the copper catalysts and phosphine ligands used in reactions. This protocol provides an efficient and practical method to synthesize the multisubstituted functionalized alkenes with specific stereoselectivity.

16.
Org Biomol Chem ; 17(25): 6122-6126, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31172157

RESUMO

A copper-catalyzed regioselective 1,4- and 1,6-conjugate addition of a silyl reagent to diendioates was established. Various 1,4- and 1,6-protosilylation products were obtained in good yields and with high regioselectivity via tuning the ligands used in the reactions. This protocol has provided a simple and efficient method for the synthesis of multisubstituted functionalized allylsilanes.

17.
Cell Biol Int ; 43(8): 910-920, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31115946

RESUMO

Silver nanoparticles (AgNps) are well established antibacterial agents, which have been reported to promote osteogenesis of stem cells. Ras homolog gene family member A (RhoA) and Tafazzin (TAZ) have been recently shown to be involved in osteogenic differentiation. The present study aimed to evaluate the effects of AgNps on osteogenic differentiation of human periodontal ligament fibroblasts (HPDLFs), and investigate the underlying mechanisms of AgNps activity. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was employed to determine the safe concentration of AgNps in HPDLFs. Using an alkaline phosphatase assay, Alizarin red S staining and detection of the expression of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), osterix (OSX), and collagen-I, we found that AgNps, at a concentration range of 25-100 µM, promoted osteogenic differentiation of HPDLFs in a dose-dependent manner. We also found that 100 µM AgNps up-regulated the active RhoA expression level. The results of ALP activity and expression of osteogenic markers showed that the effects of AgNps on osteogenic differentiation were abrogated by a RhoA pathway inhibitor, C3 reagent. Additionally, silencing of TAZ attenuated the AgNps-induced osteogenic differentiation of HPDLFs, as shown by decreased ALP activity and down-regulation of osteogenic markers. Interestingly, TAZ knockdown had a very small effect on the activity of RhoA, whereas C3 suppressed the expression of TAZ, indicating that TAZ was a downstream effector of RhoA. In conclusion, the present work demonstrated that AgNps promoted osteogenic differentiation of HPDLFs by activating the RhoA-TAZ axis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fibroblastos/metabolismo , Nanopartículas Metálicas , Osteogênese/efeitos dos fármacos , Ligamento Periodontal/citologia , Prata/farmacologia , Células Cultivadas , Humanos , Fatores de Transcrição/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
18.
J Org Chem ; 84(11): 6729-6736, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31081618

RESUMO

A Pd(II)-catalyzed mild and highly regioselective 6- endo cyclization/allylation reaction of enynoates with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert C-C double bond of allylic alcohol through cross-coupling reaction and lead to the formation of allyl pyrone via ß-OH elimination. This cascade cross-coupling reaction represents a direct and atom economic methodology for the construction of novel allyl pyrones in moderate to good yields.

19.
Org Lett ; 21(10): 3696-3700, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31070377

RESUMO

A palladium-catalyzed dialkylation of 1,3-dien-5-ynes was developed using alkenyl double bonds as the initiator and terminator for the synthesis of functionalized indene derivatives. The reactions were performed under mild reaction conditions, affording the corresponding multi-substituted indene derivatives in high efficiency via unprecedented 5- endo cyclization and alkylation processes. It was found that the substituent location at the alkenyl double bond was essential for the chemoselective synthesis of the indene and naphthalene derivatives, respectively.

20.
Front Microbiol ; 10: 1088, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139176

RESUMO

Tofu processing generates large quantities of whey as waste water. Although naturally fermented whey serves as a coagulant, the critical constituents remain unknown. High-throughput sequencing identified predominant Lactobacillus in the naturally fermented acid slurry. Lactobacillus casei YQ336 with high coagulating ability and lactic acid production was isolated and its soy protein coagulating mechanism was determined. The acid in YQ336 fermented acid slurry lowered soy milk pH and reduced negatively charged groups of denatured soy protein, leading to coagulation. Acid slurry metal ions also promoted pH decline; moreover, YQ336-produced protease might partially hydrolyse soy protein, further promoting coagulation. Thus, organic acids, metal ions, and enzymes together promote coagulation, with the former acting as the main contributing factor. This study will pave the way for future industrial application of L. casei YQ336 in acid slurry tofu processing and food manufacturing, thereby potentially reducing resource waste and environmental pollution.

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