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1.
Lancet Reg Health West Pac ; 47: 101101, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38948164

RESUMO

Background: Type 2 diabetes (T2DM) remains a challenge to treat despite the expansion of various therapeutic classes. Visepegenatide (PB-119) is a once a week, subcutaneous, glucagon-like peptide-1 receptor agonist (GLP-1 RA) injection without the requirement of dose titration that has shown glycaemic control and safety profile in two phase 2 studies conducted in China and the United States, respectively. The aim of this study was to evaluate the efficacy and safety of visepegenatide as a monotherapy in treatment-naïve patients with T2DM. Methods: This was a multicentre, double-blind, parallel, placebo-controlled, phase 3 trial conducted in 30 centres in China. Adult participants (aged 18-75 years) with T2DM, glycated haemoglobin (HbA1c) of 7.5%-11.0% [58.47-96.73 mmol/mol], body mass index (BMI) of 18-40 kg/m2, and who had been treated with diet and exercise alone for at least 8 weeks before the screening visit were eligible for enrolment. After a 4-week placebo injection run-in period, participants with HbA1c of 7.0%-10.5% [53.0-91.3 mmol/mol] and fasting plasma glucose (FPG) < 15 mmol/L were randomised in a ratio of 1:1 to receive visepegenatide (150 µg) or placebo subcutaneous injections once a week for 24 weeks. The treatment was extended to another 28 weeks during which all participants received visepegenatide. The primary outcome was a change in HbA1c from baseline to week 24. This study was registered with ClinicalTrials.gov, as NCT04504370. Findings: Between November 2, 2020, and November 2, 2022, we randomly assigned 273 adult participants to the visepegenatide (n = 137) and placebo (n = 136) groups. In total, 257 (94.12%) participants, 131 (95.6%) on visepegenatide, and 126 (92.6%) on placebo, completed the double-blinded treatment period. At baseline, the mean (SD) HbA1c was 8.47% (0.81) [69.07 [8.81] mmol/mol], which rapidly decreased to 7.63% (0.80) [59.94 [8.70] mmol/mol] with visepegenatide by week 4 of treatment, and the change from baseline was significantly greater than that in the placebo group (-0.82% [-0.90 to -0.74]; [-8.99 [-9.89 to -8.10] mmol/mol] vs -0.30% [-0.41 to -0.19]; [-3.30 [-4.50 to -2.09] mmol/mol]). At week 24, when evaluating the effects of treatment with treatment policy estimand, the least square mean (LSM change in HbA1c from baseline was -1.36 (95% confidence interval [CI] -1.52 to -1.20) [-14.84 [-16.60 to -13.08] mmol/mol] in the visepegenatide group vs -0.63 (-0.79 to -0.46) [-6.84 [-8.61 to -5.07] mmol/mol] in the placebo group. The reduction in HbA1c was significantly greater with visepegenatide than placebo (LSM difference -0.73, 95% CI -0.96 to -0.50; p < 0.001). When evaluating the treatment estimand with hypothetic policy, the LSM change in HbA1c from baseline in the visepegenatide group (-1.37 [-1.53 to -1.20]) [-14.95 [-16.76 to -13.14] mmol/mol] was significantly greater than the placebo group (-0.63 [-0.81 to -0.45]) [6.90 (-8.89 to -4.90) mmol/mol]. The LSM difference was (-0.74, 95% CI -0.98 to -0.49; [-8.00 [-10.50 to -5.50] mmol/mol]; p < 0.001]. A significantly greater proportion of the visepegenatide group achieved a target HbA1c level of <7% (<53 mmol/mol) than the placebo (50.4% vs 14.2%; p < 0.05) and stringent HbA1c level of ≤6.5% (≤48 mmol/mol) (26.7% vs 7.9%), respectively. There was also a significantly greater improvement in FPG, 2-h postprandial glucose, homeostasis model assessment (HOMA) of beta cell function, post-prandial insulin, fasting, and post-prandial C-peptide level (p < 0.05) with visepegenatide treatment. The number (3 [2.2%]) of participants who received rescue therapy in the visepegenatide group was remarkably lower compared with those (17 [12.5%]) in the placebo group (p < 0.05). During the extended treatment period, visepegenatide consistently maintained the efficacy till week 52 confirmed by all the above endpoints. The reduction in HbA1c at week 52 was -1.39% (-1.58 to -1.19) [-15.14 [-17.28 to -13.01] mmol/mol], which was even greater than that at week 24. There was also a significant improvement in HOMA-insulin resistance (p = 0.004) at week 52 compared with the baseline value. For the placebo→visepegenatide group, which received visepegenatide in the extended treatment period, a notable decrease in HbA1c at week 52 compared to baseline was observed. The change from baseline in HbA1c was -1.49% (-1.68 to -1.30) [-16.27 [-18.37 to -14.16] mmol/mol]. The outcome was in the same direction as the visepegenatide group from the double-blind treatment period. Comprehensive benefits of visepegenatide including weight loss, improvement in lipid profile, and reduction in blood pressure have been demonstrated in this study. Visepegenatide reduced the body weight in a BMI-dependent manner that was prominent in BMI ˃32 kg/m2 with a mean (SD) reduction of -4.77 (13.94) kg at week 52 (p < 0.05). Incidences of gastrointestinal adverse events were less common than other weekly GLP-1 RA in the market, and most of the adverse events were mild and moderate in nature, occurring in the first weeks of the treatment, and were transient. No serious hypoglycaemia or grade 2 hypoglycaemia (blood glucose: ≤3 mmol/L) was reported during the study. Interpretation: As a monotherapy, visepegenatide provided rapid without the risk of hypoglycaemia, significant, and sustainable glycaemic control by improving islet ß-cell function and insulin resistance. Treatment with visepegenatide induced early treatment response in reducing HbA1c and maintaining glycaemic control for 52 weeks. Meanwhile, visepegenatide provided a comprehensive benefit in body weight loss, lipids, and blood pressure reduction. Visepegenatide had a better safety profile than other weekly GLP-1 RA in participants with T2DM even without the requirement of dose titration. Visepegenatide would provide an optimal treatment approach with its high benefit and low-risk balance. Funding: PegBio Co., Ltd.

2.
J Am Chem Soc ; 146(21): 14715-14723, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38741481

RESUMO

In this work, the chemical reduction of a hybrid pyracylene-hexa-peri-hexabenzocoronene (HPH) nanographene was investigated with different alkali metals (Na, K, Rb) to reveal its remarkable multielectron acceptor abilities. The UV-vis and 1H NMR spectroscopy monitoring of the stepwise reduction reactions supports the existence of all intermediate reduction states up to the hexaanion for HPH. Tuning the experimental conditions enabled the synthesis of the HPH anions with gradually increasing reduction states (up to -5) isolated with different alkali metal ions as crystalline materials. The single-crystal X-ray diffraction structure analysis demonstrates that the highly negatively charged HPH anions (-4 and -5) exhibit a drastic geometry change from boat-shaped (observed in the neutral parent, mono- and dianions) to a chair conformation, which was proved to be fully reversible by NMR spectroscopy. DFT calculations show that this geometry change is induced by an enhanced interaction between the coordinated metal ions and negatively charged HPH core in the chair conformation.

3.
Nat Chem ; 16(6): 998-1002, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38448656

RESUMO

π-Conjugated macrocycles behave differently from analogous linear chains because their electronic wavefunctions resemble a quantum particle on a ring, leading to aromaticity or anti-aromaticity. [18]Annulene, (CH)18, is the archetypal non-benzenoid aromatic hydrocarbon. Molecules with circuits of 4n + 2 π electrons, such as [18]annulene (n = 4), are aromatic, with enhanced stability and diatropic ring currents (magnetic shielding inside the ring), whereas those with 4n π electrons, such as the dianion of [18]annulene, are expected to be anti-aromatic and exhibit the opposite behaviour. Here we use 1H NMR spectroscopy to re-evaluate the structure of the [18]annulene dianion. We also show that it can be reduced further to an aromatic tetraanion, which has the same shape as the dianion. The crystal structure of the tetraanion lithium salt confirms its geometry and reveals a metallocene-like sandwich, with five Li+ cations intercalated between two [18]annulene tetraanions. We also report a heteroleptic sandwich, with [18]annulene and corannulene tetraanion decks.

4.
Inorg Chem ; 63(21): 9579-9587, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38374612

RESUMO

A family of rare-earth complexes [RE(III) = Y, La, Gd, Tb, Dy, and Er] with doubly reduced dibenzo[a,e]cyclooctatetraene (DBCOT) has been synthesized and structurally characterized. X-ray diffraction analysis confirms that all products of the [RE(DBCOT)(THF)4][RE(DBCOT)2] composition consist of the anionic sandwich [RE(DBCOT)2]- and the cationic counterpart [RE(DBCOT)(THF)4]+. Within the sandwich, two elongated π decks are slightly bent toward the metal center (avg. 7.3°) with a rotation angle of 35.9-37.6°. The RE(III) ion is entrapped between the central eight-membered rings of DBCOT2- in a η8 fashion. The trends in the RE-COT bond lengths are consistent with the variations of the ionic radii of RE(III) centers. The 1H NMR spectra of the diamagnetic Y(III) and La(III) analogues illustrate the distinct solution behavior for the cationic and anionic parts in this series. Magnetic measurements for the Dy analogue reveal single-molecule magnetism, which was rationalized by considering the effect of crystal-field splitting for both building units analyzed by electronic structure calculations.

5.
Chem Sci ; 14(48): 14109-14114, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38098717

RESUMO

[24]Paracyclophanetetraene is a classic example of a macrocyclic hydrocarbon that becomes globally aromatic on reduction to the di-anion, and switches to globally anti-aromatic in the tetra-anion. This redox activity makes it promising as an electrode material for batteries. Here, we report the solid-state structures of the di- and tetra-anions of this cyclophane, in several coordination environments. The changes in bond length on reduction yield insights into the global aromaticity of the di-anion (26π electrons), and anti-aromaticity of the tetra-anion (28π electrons), that were previously deduced from NMR spectra of species generated in situ. The experimental geometries of the aromatic di-anion and anti-aromatic tetra-anion from X-ray crystallographic data match well with gas-phase calculated structures, and reproduce the low symmetry expected in the anti-aromatic ring. Comparison of coordinated and naked anions confirms that metal coordination has little effect on the bond lengths. The UV-vis-NIR absorption spectra show a sharp intense peak at 878 nm for the di-anion, whereas the tetra-anion gives a broad spectrum typical of an anti-aromatic system.

6.
Chem Sci ; 14(45): 13219-13227, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38023520

RESUMO

As a planar subunit of C60-fullerene, truxene (C27H18) represents a highly symmetrical rigid hydrocarbon with strong blue emission. Herein, we used truxene as a model to investigate the chemical reactivity of a fullerene fragment with alkali metals. Monoanion, dianion, and trianion products with different alkali metal counterions were crystallized and fully characterized, revealing the core curvature dependence on charge and alkali metal coordination. Moreover, a 1proton nuclear magnetic resonance study coupled with computational analysis demonstrated that deprotonation of the aliphatic CH2 segments introduces aromaticity in the five-membered rings. Importantly, the UV-vis absorption and photoluminescence of truxenyl anions with different charges reveal intriguing charge-dependent optical properties, implying variation of the electronic structure based on the deprotonation process. An increase in aromaticity and π-conjugation yielded a red shift in the absorption and photoluminescent spectra; in particular, large Stokes shifts were observed in the truxenyl monoanion and dianion with high emission quantum yield and time of decay. Overall, stepwise deprotonation of truxene provides the first crystallographically characterized examples of truxenyl anions with three different charges and charge-dependent optical properties, pointing to their potential applications in carbon-based functional materials.

7.
Angew Chem Int Ed Engl ; 62(34): e202307750, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37365137

RESUMO

We report a facile synthesis of diindeno-fused dibenzo[a,h]anthracene derivatives (DIDBA-2Cl, DIDBA-2Ph, and DIDBA-2H) with different degrees of non-planarity using three substituents (chloro, phenyl, and hydrogen) of various sizes. The planarization of their cores, as evidenced by the decreased end-to-end torsional angles, was confirmed by X-ray crystallography. Their enhanced energy gaps with twisting were investigated by a combination of spectroscopic and electrochemical methods with density functional theory, which showed a transition from singlet open-shell to closed-shell configuration. Moreover, their doubly reduced states, DIDBA-2Ph2- and DIDBA-2H2- , were achieved by chemical reduction. The structures of dianions were identified by X-ray crystallographic analysis, which elucidated that the electron charging further distorted the backbones. The electronic structure of the dianions was demonstrated by experimental and theoretical approaches, suggesting decreased energy gaps with larger non-planarity, different from the neutral species.

8.
J Clin Endocrinol Metab ; 108(10): 2728-2738, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37029975

RESUMO

CONTEXT: According to growing research, C1q/TNF-Related Protein-9 (CTRP9) appears to be linked to type 2 diabetes mellitus (T2DM). But the literature on circulating levels of CTRP9 in patients with T2DM has been contradictory. OBJECTIVE: This is a systematic review and meta-analysis to reassess the circulating level of CTRP9 in patients with T2DM, with and without complications. METHODS: Relevant studies published until October 31, 2021, were identified from the PubMed, Embase, Web of Science, Cochrane Library, WanFang, CNKI, VIP, and CBM databases. Participants with age ≥18 years with clinically diagnosed T2DM were included. Sex and diabetes complications were not restricted. The data were extracted by 2 reviewers independently using a standard data collection form. RESULTS: Analysis demonstrated significantly lower circulating levels of CTRP9 in patients with T2DM than in patients without diabetes (standardized mean difference [SMD] = -1.36; 95% CI -1.78 to -0.93; P < .001), I2 = 97.5%, P < .001). Furthermore, the circulating level of CTRP9 in patients with T2DM-related complications was lower than that in patients with T2DM without complications, regardless of macrovascular complications or microvascular complications (SMD = -1.062; 95% CI -1.466 to -0.658; P < .001, I2 = 91.3%, P < .001). Subgroup analyses revealed that factors such as body mass index, T2DM duration, and fasting blood glucose were the sources of heterogeneity (P = .047, P = .034, and P = .07, respectively). CONCLUSION: The present systematic review and meta-analysis found CTRP9 levels were lower in T2DM patients with or without complications. However, since this was a meta-analysis of most observational studies, these findings still need to be verified by further studies with a large sample size.


Assuntos
Diabetes Mellitus Tipo 2 , Adolescente , Humanos , Proteínas
9.
Chemistry ; 29(27): e202300388, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-36749878

RESUMO

The electronic, optical, and solid state properties of a series of monoradicals, anions and cations obtained from starting neutral diradicals have been studied. Diradicals based on s-indacene and indenoacenes, with benzothiophenes fused and in different orientations, feature a varying degree of diradical character in the neutral state, which is here related with the properties of the radical redox forms. The analysis of their optical features in the polymethine monoradicals has been carried out in the framework of the molecular orbital and valence bond theories. Electronic UV-Vis-NIR absorption, X-ray solid-state diffraction and quantum chemical calculations have been carried out. Studies of the different positive-/negative-charged species, both residing in the same skeletal π-conjugated backbone, are rare for organic molecules. The key factor for the dual stabilization is the presence of the starting diradical character that enables to indistinctively accommodate a pseudo-hole and a pseudo-electron defect with certainly small reorganization energies for ambipolar charge transport.

10.
Acta Pharmacol Sin ; 44(2): 446-453, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35896694

RESUMO

The current study evaluated the efficacy and safety of a denosumab biosimilar, QL1206 (60 mg), compared to placebo in postmenopausal Chinese women with osteoporosis and high fracture risk. At 31 study centers in China, a total of 455 postmenopausal women with osteoporosis and high fracture risk were randomly assigned to receive QL1206 (60 mg subcutaneously every 6 months) or placebo. From baseline to the 12-month follow-up, the participants who received QL1206 showed significantly increased bone mineral density (BMD) values (mean difference and 95% CI) in the lumbar spine: 4.780% (3.880%, 5.681%), total hip :3.930% (3.136%, 4.725%), femoral neck 2.733% (1.877%, 3.589%) and trochanter: 4.058% (2.791%, 5.325%) compared with the participants who received the placebo. In addition, QL1206 injection significantly decreased the serum levels of C-terminal crosslinked telopeptides of type 1 collagen (CTX): -77.352% (-87.080%, -66.844%), and N-terminal procollagen of type l collagen (P1NP): -50.867% (-57.184%, -45.217%) compared with the placebo over the period from baseline to 12 months. No new or unexpected adverse events were observed. We concluded that compared with placebo, QL1206 effectively increased the BMD of the lumbar spine, total hip, femoral neck and trochanter in postmenopausal Chinese women with osteoporosis and rapidly decreased bone turnover markers. This study demonstrated that QL1206 has beneficial effects on postmenopausal Chinese women with osteoporosis and high fracture risk.


Assuntos
Medicamentos Biossimilares , Conservadores da Densidade Óssea , Osteoporose Pós-Menopausa , Osteoporose , Feminino , Humanos , Medicamentos Biossimilares/efeitos adversos , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea , Denosumab/uso terapêutico , Denosumab/farmacologia , Método Duplo-Cego , População do Leste Asiático , Osteoporose/tratamento farmacológico , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/tratamento farmacológico , Pós-Menopausa
11.
Cell Cycle ; 21(15): 1590-1598, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35451342

RESUMO

Diabetic retinopathy (DR) as a frequent diabetic microvascular complication shows signs in one-third of diabetic patients. Long non-coding RNAs (lncRNAs) have drawn increasing attention because of their regulatory roles in DR. LncRNA plasmacytoma variant translocation 1 (PVT1) is documented to be upregulated in diabetes-related diseases, while its effects in DR remains unexplored. ARPE-19 cells under the treatment of high-glucose (HG) were used as DR cell models. The gene expression in ARPE-19 cells was examined using RT-qPCR. The viability and apoptosis of ARPE-19 cells were determined by MTT and TUNEL assays. The levels of inflammation-associated proteins or mRNA were measured using western blot. Luciferase reporter assay and RNA pull down assay were conducted for the exploration of the underlying mechanism of PVT1. PVT1 was revealed to be upregulated in DR cell models. Silencing of PVT1 promoted the viability and inhibited apoptosis of HG-stimulated ARPE-19 cells. The results revealed that PVT1 can bind with miR-1301-3p. PVT1 negatively modulated miR-1301-3p expression. Additionally, KLF7 was targeted by miR-1301-3p. PVT1 upregulated KLF7 expression by binding with miR-1301-3p. The silenced PVT1-mediated influence on cell viability and cell apoptosis was rescued by overexpression of KLF7. PVT1 suppresses proliferation and promotes apoptosis of ARPE-19 cells treated with HG in vitro by binding with miR-1301-3p to upregulate KLF7.


Assuntos
Apoptose , Fatores de Transcrição Kruppel-Like , MicroRNAs , RNA Longo não Codificante , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais
12.
Chem Commun (Camb) ; 58(37): 5574-5577, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35353101

RESUMO

The chemical reduction of a corannulene-based molecular nanographene, C76H64 (1), with Na metal in the presence of 18-crown-6 afforded the doubly-reduced state of 1. This reduction provokes a distortion of the helicene core and has a significant impact on the aromaticity of the system.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Íons , Metais , Hidrocarbonetos Policíclicos Aromáticos/química , Sódio
13.
Chem Commun (Camb) ; 58(19): 3206-3209, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35174826

RESUMO

The chemical reduction of a π-expanded COT derivative, octaphenyltetrabenzocyclooctatetraene (1), with lithium or sodium metals in the presence of secondary ligands affords a new doubly-reduced product (1TR2-). The X-ray diffraction study revealed a reductive core rearrangement accompanied by the formation of a single C-C bond and severe twist of the central tetraphenylene core. The reversibility of two-electron reduction and core transformation is further confirmed by NMR spectroscopy and DFT calculations.

14.
Angew Chem Int Ed Engl ; 61(10): e202115747, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34875130

RESUMO

The chemical reduction of π-conjugated bilayer nanographene 1 (C138 H120 ) with K and Rb in the presence of 18-crown-6 affords [K+ (18-crown-6)(THF)2 ][{K+ (18-crown-6)}2 (THF)0.5 ][C138 H122 3- ] (2) and [Rb+ (18-crown-6)2 ][{Rb+ (18-crown-6)}2 (C138 H122 3- )] (3). Whereas K+ cations are fully solvent-separated from the trianionic core thus affording a "naked" 1.3 - anion, Rb+ cations are coordinated to the negatively charged layers of 1.3 - . According to DFT calculations, the localization of the first two electrons in the helicene moiety leads to an unprecedented site-specific hydrogenation process at the carbon atoms located on the edge of the helicene backbone. This uncommon reduction-induced site-specific hydrogenation provokes dramatic changes in the (electronic) structure of 1 as the helicene backbone becomes more compressed and twisted upon chemical reduction, which results in a clear slippage of the bilayers.

15.
Inflamm Res ; 70(10-12): 1113-1127, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34591118

RESUMO

OBJECTIVE: Diabetic cardiomyopathy (DCM) is a serious complication of diabetes, but its pathogenesis is still unclear. This study investigated the mechanism of long noncoding RNA (lncRNA) NORAD in DCM. METHODS: Male leptin receptor-deficient (db/db) mice and leptin control mice (db/ +) were procured. DCM model was established by subcutaneous injection of angiotensin II (ATII) in db/db mice. NORAD lentivirus shRNA or Adv-miR-125a-3p was administered to analyze cardiac function, fibrosis, serum biochemical indexes, inflammation and fibrosis. Primary cardiomyocytes were extracted and transfected with miR-125a-3p mimic. The competing endogenous RNA (ceRNA) network of NORAD/miR-125a-3p/Fyn was verified. The levels of fibrosis- and inflammation-related factors were measured. RESULTS: In db/db mice treated with ATII, the body weight and serum biochemical indexes were increased, while the cardiac function was decreased, and inflammatory cell infiltration and fibrosis were induced. NORAD was upregulated in diabetic and DCM mice. The 4-week intravenous injection of NORAD lentivirus shRNA reduced body weight and serum biochemical indexes, improved cardiac function, and attenuated inflammation and fibrosis in DCM mice. NORAD acted as a sponge to adsorb miR-125a-3p, and miR-125a-3p targeted Fyn. Intravenous injection of miR-125a-3p adenovirus improved cardiac function and fibrosis and reduced inflammatory responses in DCM mice. Co-overexpression of miR-125-3p and Fyn partly reversed the improving effect of miR-125-3p overexpression on cardiac fibrosis in DCM mice. CONCLUSION: NORAD lentivirus shRNA improved cardiac function and fibrosis and reduced inflammatory responses in DCM mice via the ceRNA network of NORAD/miR-125a-3p/Fyn. These findings provide a valuable and promising therapeutic target for the treatment of DCM.


Assuntos
Cardiomiopatias Diabéticas/genética , MicroRNAs , Proteínas Proto-Oncogênicas c-fyn/genética , RNA Longo não Codificante , Animais , Citocinas/imunologia , Cardiomiopatias Diabéticas/imunologia , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Fibrose , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Inflamação/fisiopatologia , Lentivirus/genética , Masculino , Camundongos Knockout , Miocárdio/imunologia , Miocárdio/patologia , RNA Interferente Pequeno , Receptores para Leptina/genética , Função Ventricular Esquerda
16.
Front Mol Biosci ; 8: 685466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422901

RESUMO

Background: Increasing attention has been attracted by the role of circular RNAs (circRNAs) in ocular diseases. Previous study has revealed that circ_0005941 (also known as circFTO, an alpha-ketoglutarate-dependent dioxygenase) was upregulated in the vitreous humor of diabetic retinopathy (DR), while its underlying mechanism in DR remains unknown. Methods: Retinal vascular endothelial cells (RVECs) treated with high glucose (HG) were used to establish the DR cell model. The in vivo assays were conducted using streptozotocin-induced diabetic mice. The circular structure and stability of circFTO were identified by Sanger sequencing and RNase R treatment. RT-qPCR analysis was used to detect the RNA expression. The levels of the mRNA-encoded protein thioredoxin-interacting protein (TXNIP) or angiogenesis-associated proteins (VEGFA, PDGF, and ANG2) and blood-retinal barrier (BRB)-related proteins (ZO-1, Occludin, and Claudin-5) were measured by Western blot. The viability of RVECs was measured using CCK-8 assays. The angiogenesis of RVECs was assessed using tube formation assays in vitro. Endothelial permeability assays were conducted to examine the function of the BRB. The binding between genes was explored using RNA pulldown and luciferase reporter assays. Results: CircFTO was upregulated in HG-treated RVECs. CircFTO deficiency reversed the HG-induced increase in the viability and angiogenesis of RVECs and alleviated HG-mediated impairment of the BRB. MiR-128-3p bound with circFTO and was downregulated in HG-treated RVECs. TXNIP was a downstream target gene of miR-128-3p. TXNIP was highly expressed in the DR cell model. Rescue assays revealed that circFTO promoted angiogenesis and impaired the blood-retinal barrier by upregulating TXNIP. In the DR mouse model, circFTO silencing inhibited angiogenesis and promoted BRB recovery in vivo. Conclusion: CircFTO promotes angiogenesis and impairs the blood-retinal barrier in vitro and in vivo by binding with miR-128-3p to upregulate TXNIP in DR.

17.
J Food Biochem ; 45(6): e13753, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955004

RESUMO

Subclinical hypothyroidism (SCH) as mild thyroid disorder or comorbidity in patients with endocrine disorders is closely related with insulin resistance (IR) and poor glycemic control. The present study attempted to investigate the effect of SCH on IR and glycemic control in patients with type 2 diabetes mellitus (T2DM). In addition, the effects of ellagic acid (EA) on SCH C57BL/6J and db/db mice were also investigated to explore potential therapeutic drug against SCH-induced abnormal glucose metabolism. T2DM patients were recruited in our study and categorized into two groups according to thyroid stimulating hormone (TSH) value: T2DM without SCH group (TSH ≤4 µIU/ml; n = 30) and T2DM with SCH group (TSH >4µIU/ml; n = 60). Methimazole (MMI; 0.08 mg kg-1  day-1 ) was intragastrically administrated for 12 weeks to establish SCH in C57BL/6J and db/db mice. Compared with T2DM patients without SCH, poor glycemic and cholesterol control were emerged in T2DM patients with SCH and that were prominent in patients with TSH more than 10 µIU/ml. In addition, a significant positive correlation between serum TSH and fasting plasma-glucose (FPG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), or glycated hemoglobin (HbA1c) was observed in T2DM patients with SCH. Moreover, abnormal glucose metabolism in C57BL/6J and db/db mice with SCH has been attenuated by EA administration. Our findings provided data regarding the positive correlation between high TSH level with poor glycemic control in T2DM patients with SCH. EA might be a supportive strategy for preventing SCH-induced abnormal glucose metabolism. PRACTICAL APPLICATIONS: Subclinical hypothyroidism (SCH) is a potential risk factor associated with abnormal glucose metabolism in patients with type 2 diabetes mellitus (T2DM). A clinical theory of a positive correlation between high TSH level and poor glycemic control was validated in type 2 diabetes mellitus patients and mouse models. Ellagic acid (EA) might be a supportive strategy for preventing SCH-induced abnormal glucose metabolism that provided a treatment option in T2DM patients with subclinical hypothyroidism in clinical practice.


Assuntos
Diabetes Mellitus Tipo 2 , Hipotireoidismo , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácido Elágico/farmacologia , Glucose , Controle Glicêmico , Humanos , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/tratamento farmacológico , Metimazol , Camundongos , Camundongos Endogâmicos C57BL
18.
J Am Chem Soc ; 143(13): 5231-5238, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33764047

RESUMO

This study explores a bottom-up approach toward negatively curved carbon allotropes from octabenzo[8]circulene, a negatively curved nanographene. Stepwise chemical reduction reactions of octabenzo[8]circulene with alkali metals lead to a unique highly reduced hydrocarbon pentaanion, which is revealed by X-ray crystallography suggesting a local view for the reduction and alkali metal intercalation processes of negatively curved carbon allotropes. Polymerization of the tetrabromo derivative of octabenzo[8]circulene by the nickel-mediated Yamamoto coupling reaction results in a new type of porous carbon-rich material, which consists of a covalent network of negatively curved nanographenes. It has a specific surface area of 732 m2 g-1 and functions as anode material for lithium ion batteries exhibiting a maximum capacity of 830 mAh·g-1 at a current density of 100 mA·g-1. These results indicate that this covalent network presents the key structural and functional features of negatively curved carbon allotropes.

19.
Angew Chem Int Ed Engl ; 60(7): 3510-3514, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33108043

RESUMO

The chemical reduction of a π-expanded polycyclic framework comprising a cyclooctatetraene moiety, octaphenyltetrabenzocyclooctatetraene, with lithium metal readily affords the corresponding tetra-anion instead of the expected aromatic dianion. As revealed by X-ray crystallography, the highly contorted tetra-anion is stabilized by coordination of two internally bound Li+ , while two external cations remain solvent separated. The variable-temperature 7 Li NMR spectra in THF confirm the presence of three types of Li+ ions and clearly differentiate internal binding, consistent with the crystal structure. Density-functional theory calculations suggest that the formation of the highly charged tetra-reduced carbanion is stabilized through Li+ coordination under the applied experimental conditions.

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