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1.
J Am Chem Soc ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489242

RESUMO

We present the first example of an 99TcO4- anion entrapped within the cavity of a silver cluster, revealing an unprecedented photoinduced charge transfer phenomenon. [Ag24(C≡CtBu)20(99TcO4)]·(BF4)3 (denoted as 99TcO4-@Ag24) was successfully synthesized and structurally characterized. Single-crystal X-ray diffraction and Raman spectroscopy reveal that the tetrahedral structure of the 99TcO4- anion sustains significant symmetry breaking with weakened Tc-O bond strength under confinement within the Ag24(C≡CtBu)204+ cluster. Notably, 99TcO4-@Ag24 exhibits a broadband electronic absorption spectrum in the visible region, which was absent for the other 99TcO4--containing compounds. Density functional theory calculations elucidate that host-guest electrostatic interactions result in an electron polarization effect between the 99TcO4- anion core and the Ag24 cationic shell. The emergence of an absorption band in 99TcO4-@Ag24 is rationalized by intermolecular charge transfer from the Ag24 electronic states to the lowest unoccupied molecular orbitals of 99TcO4- instead of the intramolecular electron transition observed in other 99TcO4--containing compounds.

2.
Exp Ther Med ; 26(4): 473, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37753299

RESUMO

Rapamycin-insensitive companion of mTOR (Rictor) is a critical effector of mTOR protein complex 2 (mTORC2). The aim of the present study was to investigate the effect of Rictor in the mTORC2 signaling pathway in high glucose (HG)-induced diabetic podocyte injury by silencing the expression of Rictor. In the present study, mouse podocytes were treated with glucose (150 mM) and mannitol (200 mM), the Rictor gene was silenced using small interfering RNA (siRNA). Apoptosis was detected by flow cytometry, whereas podocyte cytoskeletal protein expression was detected by western blotting (WB) and immunofluorescence staining. The results demonstrated that, compared with that in the control group, the podocyte apoptotic rate was significantly increased in the mannitol group (negative group) and the groups that were treated with glucose (model groups). The podocyte apoptotic rate in the model + Rictor siRNA group was significantly decreased compared with that in the negative, model and the model glucose + siRNA negative control (NC) groups. WB indicated that the protein expression levels of podocalyxin and synaptopodin were reduced in the model and model + siRNA NC groups compared with those in the normal control and negative groups. Additionally, the protein expression levels of α-smooth muscle actin (α-SMA) and P-AKT/AKT were increased in the model and model + siRNA NC groups compared with the those in control and negative groups. Compared with those the model and model + siRNA NC groups, the protein expression levels of podocalyxin and synaptopodin were increased, whilst those of the α-SMA and P-AKT/AKT proteins were decreased, in the model + Rictor siRNA group. Results from immunofluorescence analysis were basically consistent with those of WB. Therefore, results of the present study suggest that silencing of the Rictor gene may reduce the damage to podocytes induced by HG, such that the Rictor/mTORC2 signaling pathway may be involved in the remodeling of podocyte actin cytoskeletal in diabetes.

3.
DNA Cell Biol ; 38(8): 865-873, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31225740

RESUMO

Accumulating evidence has suggested that microRNAs play important roles in the development of hepatocellular carcinoma (HCC) and are involved in drug resistance. miR-21-5p was overexpressed in a variety of cancers and promoted the tumorigenesis; however, the function of miR-21-5p in HCC still remains unknown. In this study, our results showed that miR-21-5p was highly expressed in HCC tissues and cell lines. Notably, the level of miR-21-5p was relatively higher in cisplatin (DDP)-resistant HCC patients. Overexpression of miR-21-5p attenuated the inhibitory effect of DDP on the proliferation and apoptosis of HCC cells. Mechanistically, the luciferase report assay-identified FAS ligand (FASLG) was a direct target of miR-21-5p. Overexpression of miR-21-5p decreased both the mRNA and protein levels of FASLG in HCC cells. FASLG was downregulated in HCC tissues and was significantly negatively correlated with the expression of miR-21-5p. Restoring the expression of FASLG upregulated the chemosensitivity of HCC cells expressing miR-21-5p. In conclusion, our results demonstrated that miR-21-5p targeted FASLG and suppressed the sensitivity of HCC cells to DDP treatment.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Cisplatino/farmacologia , Proteína Ligante Fas/genética , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/genética , Idoso , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Ligante Fas/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Life Sci ; 224: 67-75, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30684546

RESUMO

Type 2 diabetes mellitus (T2DM) is a progressive disease, accompanied by increased insulin resistance and deteriorating ß-cell function. Previous studies have revealed that microRNA (miRNA) plays a crucial role in the treatment of T2DM. Hence, we aim to investigate the role of microRNA-125b-5p (miR-125b-5p) in pancreatic ß-cell function and insulin sensitivity of mice with T2DM with the involvement of Dishevelled antagonist Dapper1 (DACT1) and the c-Jun NH2-terminal kinases (JNK) signaling pathway. Firstly, a mouse model of T2DM was established by administering a high-fat diet plus low dosage of streptozotocin, and function of pancreatic ß-cell and insulin sensitivity in the normal and T2DM mice were detected. Then, the pancreatic ß-cells were collected from pancreatic islet tissues and treated with different mimics, inhibitors and siRNAs. After that, the relationship among miR-125b-5p, DACT1, and the JNK signaling-related factors in T2DM mice was determined. Finally, cell proliferation and apoptosis were determined. Mice with T2DM had lower pancreatic ß-cell function and insulin sensitivity, as well as diminished expression of miR-125b-5p but enhanced expressions of DACT1, JNK and c-Jun. miR-125b-5p inhibited DACT1 expression and the activation of the JNK signaling pathway, as well as restrained cell proliferation and promoted cell apoptosis. The current results suggest that up-regulated miR-125b-5p promotes insulin sensitivity and enhances pancreatic ß-cell function through inhibiting the JNK signaling pathway by negatively mediating DACT1.


Assuntos
Proliferação de Células , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 2/prevenção & controle , Células Secretoras de Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases , MicroRNAs/genética , Animais , Apoptose , Diferenciação Celular , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Resistência à Insulina , Células Secretoras de Insulina/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas de Ligação a RNA , Transdução de Sinais
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