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1.
J Environ Manage ; 357: 120783, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579475

RESUMO

The rapid development of the economy and society is causing an increase in the amount of municipal solid waste (MSW) produced by people's daily lives. With the strong support of the Chinese government, incineration power generation has steadily become the primary method of treating MSW, accounting for 79.86%. However, burning produces a significant amount of municipal solid waste incineration fly ash (MSWI-FA), which contains heavy metals, soluble chlorine salts, and dioxins. China's MSWI-FA yield increased by 8.23% annually to 7.80 million tons in 2022. Besides, the eastern region, especially the southeastern coastal region, has the highest yield of MSWI-FA. There are certain similarities in the chemical characteristics of MSWI-FA samples from Northeast, North, East, and South China. Zn and CaO have the largest amounts of metals and oxides, respectively. The Cl content is about 20 wt%. This study provides an overview of the techniques used in the thermal treatment method, solidification and stabilization, and separation and extraction of MSWI-FA and compares their benefits and drawbacks. In addition, the industrial applications and standard requirements of landfill treatment and resource utilization of MSWI-FA in China are analyzed. It is discovered that China's resource utilization of MSWI-FA is insufficient through the study on the fly ash disposal procedures at a few MSW incineration facilities located in the economically developed Guangdong Province and the traditional industrial city of Tianjin. Finally, the prospects for the disposal of MSWI-FA were discussed.


Assuntos
Metais Pesados , Eliminação de Resíduos , Humanos , Cinza de Carvão/química , Resíduos Sólidos/análise , Material Particulado/análise , Carbono/análise , Incineração , Metais Pesados/análise , China
2.
Nucleic Acids Res ; 49(7): 4129-4143, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33784404

RESUMO

Pif1 is an SF1B helicase that is evolutionarily conserved from bacteria to humans and plays multiple roles in maintaining genome stability in both nucleus and mitochondria. Though highly conserved, Pif1 family harbors a large mechanistic diversity. Here, we report crystal structures of Thermus oshimai Pif1 (ToPif1) alone and complexed with partial duplex or single-stranded DNA. In the apo state and in complex with a partial duplex DNA, ToPif1 is monomeric with its domain 2B/loop3 adopting a closed and an open conformation, respectively. When complexed with a single-stranded DNA, ToPif1 forms a stable dimer with domain 2B/loop3 shifting to a more open conformation. Single-molecule and biochemical assays show that domain 2B/loop3 switches repetitively between the closed and open conformations when a ToPif1 monomer unwinds DNA and, in contrast with other typical dimeric SF1A helicases, dimerization has an inhibitory effect on its helicase activity. This mechanism is not general for all Pif1 helicases but illustrates the diversity of regulation mechanisms among different helicases. It also raises the possibility that although dimerization results in activation for SF1A helicases, it may lead to inhibition for some of the other uncharacterized SF1B helicases, an interesting subject warranting further studies.


Assuntos
Proteínas de Bactérias , DNA Helicases , DNA de Cadeia Simples/metabolismo , Thermus/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , DNA Helicases/química , DNA Helicases/metabolismo , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Multimerização Proteica
3.
Cell Mol Life Sci ; 78(19-20): 6557-6583, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34459951

RESUMO

G-quadruplex (G4) DNA is a type of quadruple helix structure formed by a continuous guanine-rich DNA sequence. Emerging evidence in recent years authenticated that G4 DNA structures exist both in cell-free and cellular systems, and function in different diseases, especially in various cancers, aging, neurological diseases, and have been considered novel promising targets for drug design. In this review, we summarize the detection method and the structure of G4, highlighting some non-canonical G4 DNA structures, such as G4 with a bulge, a vacancy, or a hairpin. Subsequently, the functions of G4 DNA in physiological processes are discussed, especially their regulation of DNA replication, transcription of disease-related genes (c-MYC, BCL-2, KRAS, c-KIT et al.), telomere maintenance, and epigenetic regulation. Typical G4 ligands that target promoters and telomeres for drug design are also reviewed, including ellipticine derivatives, quinoxaline analogs, telomestatin analogs, berberine derivatives, and CX-5461, which is currently in advanced phase I/II clinical trials for patients with hematologic cancer and BRCA1/2-deficient tumors. Furthermore, since the long-term stable existence of G4 DNA structures could result in genomic instability, we summarized the G4 unfolding mechanisms emerged recently by multiple G4-specific DNA helicases, such as Pif1, RecQ family helicases, FANCJ, and DHX36. This review aims to present a general overview of the field of G-quadruplex DNA that has progressed in recent years and provides potential strategies for drug design and disease treatment.


Assuntos
DNA/genética , Animais , Replicação do DNA/genética , Desenho de Fármacos , Epigênese Genética/genética , Quadruplex G , Humanos , Telômero/genética , Transcrição Gênica/genética
4.
Int J Clin Pract ; 2022: 7581110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910069

RESUMO

Background: Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are widely used in the treatment of hypertension. Hypertension is often accompanied by osteoporosis. However, the relationship between ACEI/ARB and fractures remains controversial. The purpose of this meta-analysis was to update the potential relationship between ACEI/ARB and fractures. Methods: This meta-analysis was identified through PubMed, EMBASE, Cochrane Library, and Web of Science. Related studies about ACEI/ARB with the risk of fracture were published from inception to June 2022. Results: Nine qualified prospective designed studies, involving 3,649,785 subjects, were included in this analysis. Overall, the RRs of ACEI compared with the nonusers were 0.98 (95% CI: 0.88, 1.10; P < 0.001) for composite fractures and 0.96 (95% CI: 0.87, 1.05; P=0.048) for hip fractures; the RRs of ARB compared to the nonusers were 0.82 (95% CI: 0.73, 0.91; P < 0.001) for composite fractures and 0.85 (95% CI: 0.74, 0.97; P=0.028) for hip fractures. Furthermore, in the subgroup analysis, male may benefit from ARB (RR = 0.65, 95% CI: 0.49, 0.89, P=0.028), and the European may also benefit from ARB (RR = 0.86, 95% CI: 0.80, 0.93, P=0.015). Conclusions: ACEI usage will not decrease the risk of osteoporosis fracture. On the contrary, ARB usage can decrease the risk of total fracture and hip fracture, especially for males and Europeans. Compared with ACEI, for patients at higher risk of fracture in cardiovascular diseases such as hypertension, the protective effect of ARB should be considered.


Assuntos
Fraturas do Quadril , Hipertensão , Osteoporose , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Estudos Prospectivos
5.
J Biol Chem ; 295(51): 17646-17658, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33454004

RESUMO

RecQ family helicases are highly conserved from bacteria to humans and have essential roles in maintaining genome stability. Mutations in three human RecQ helicases cause severe diseases with the main features of premature aging and cancer predisposition. Most RecQ helicases shared a conserved domain arrangement which comprises a helicase core, an RecQ C-terminal domain, and an auxiliary element helicase and RNaseD C-terminal (HRDC) domain, the functions of which are poorly understood. In this study, we systematically characterized the roles of the HRDC domain in E. coli RecQ in various DNA transactions by single-molecule FRET. We found that RecQ repetitively unwinds the 3'-partial duplex and fork DNA with a moderate processivity and periodically patrols on the ssDNA in the 5'-partial duplex by translocation. The HRDC domain significantly suppresses RecQ activities in the above transactions. In sharp contrast, the HRDC domain is essential for the deep and long-time unfolding of the G4 DNA structure by RecQ. Based on the observations that the HRDC domain dynamically switches between RecA core- and ssDNA-binding modes after RecQ association with DNA, we proposed a model to explain the modulation mechanism of the HRDC domain. Our findings not only provide new insights into the activities of RecQ on different substrates but also highlight the novel functions of the HRDC domain in DNA metabolisms.


Assuntos
DNA/metabolismo , Escherichia coli/enzimologia , Quadruplex G , RecQ Helicases/metabolismo , Reparo do DNA , Transferência Ressonante de Energia de Fluorescência , Humanos , Mutagênese Sítio-Dirigida , Conformação de Ácido Nucleico , Ligação Proteica , Domínios Proteicos , Estrutura Terciária de Proteína , RecQ Helicases/química , RecQ Helicases/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Especificidade por Substrato
6.
Nucleic Acids Res ; 45(19): 11401-11412, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-28977514

RESUMO

G-quadruplex (G4) can be formed by G-rich DNA sequences that are widely distributed throughout the human genome. Although G-triplex and G-hairpin have been proposed as G4 folding intermediates, their formation still requires further investigation by experiments. Here, we employed single-molecule FRET to characterize the folding dynamics of G4 from human telomeric sequence. First, we observed four states during G4 folding initially assigned to be anti-parallel G4, G-triplex, G-hairpin and unfolded ssDNA. Then we constructed putative intra-strand G-triplex, G-hairpin structures and confirmed their existences in both NaCl and KCl. Further studies revealed those structures are going through dynamic transitions between different states and show relatively weak dependence on cations, unlike G4. Based on those results and molecular dynamics simulations, we proposed a multi-pathway folding mechanism for human telomeric G4. The present work may shed new light on our current understanding about the existence and stability of G4 intermediate states.


Assuntos
DNA/química , Quadruplex G , Conformação de Ácido Nucleico , Telômero/genética , DNA/genética , Transferência Ressonante de Energia de Fluorescência , Humanos , Cinética , Microscopia de Fluorescência , Simulação de Dinâmica Molecular , Transdução de Sinais/genética
7.
Biomed Pharmacother ; 177: 117065, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971010

RESUMO

Metabolic diseases are a group of disorders caused by metabolic abnormalities, including obesity, diabetes, non-alcoholic fatty liver disease, and more. Increasing research indicates that, beyond inherent metabolic irregularities, the onset and progression of metabolic diseases are closely linked to alterations in the gut microbiota, particularly gut bacteria. Additionally, fecal microbiota transplantation (FMT) has demonstrated effectiveness in clinically treating metabolic diseases, notably diabetes. Recent attention has also focused on the role of gut viruses in disease onset. This review first introduces the characteristics and influencing factors of gut viruses, then summarizes their potential mechanisms in disease development, highlighting their impact on gut bacteria and regulation of host immunity. We also compare FMT, fecal filtrate transplantation (FFT), washed microbiota transplantation (WMT), and fecal virome transplantation (FVT). Finally, we review the current understanding of gut viruses in metabolic diseases and the application of FVT in treating these conditions. In conclusion, FVT may provide a novel and promising treatment approach for metabolic diseases, warranting further validation through basic and clinical research.


Assuntos
Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Doenças Metabólicas , Viroma , Humanos , Transplante de Microbiota Fecal/métodos , Doenças Metabólicas/terapia , Animais , Fezes/virologia , Fezes/microbiologia
8.
Biosci Rep ; 43(7)2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37293973

RESUMO

Obesity, characterized by accumulation of adipose, is usually accompanied by hyperlipidemia and abnormal glucose metabolism, which destroys the function and structure of islet ß cells. However, the exact mechanism of islet deterioration caused by obesity has not yet been fully elucidated. Here, we fed C57BL/6 mice with a high-fat diet (HFD) for 2 (2M group) and 6 months (6M group) to construct obesity mouse models. Then, RNA-based sequencing was used to identify the molecular mechanisms in HFD-induced islet dysfunction. Compared with the control diet, a total of 262 and 428 differentially expressed genes (DEGs) were identified from islets of the 2M and 6M groups, respectively. GO and KEGG enrichment analysis revealed that the DEGs up-regulated in both the 2M and 6M groups are mainly enriched in response to endoplasmic reticulum stress and the pancreatic secretion pathway. DEGs down-regulated in both the 2M and 6M groups are mainly enriched in the neuronal cell body and protein digestion and absorption pathway. Notably, along with the HFD feeding, mRNA expression of islet cell markers was significantly down-regulated, such as Ins1, Pdx1, MafA (ß cell), Gcg, Arx (α cell), Sst (δcell), and Ppy (PP cell). In contrast, mRNA expression of acinar cell markers was remarkably up-regulated, such as Amy1, Prss2, and Pnlip. Besides, a large number of collagen genes were down-regulated, such as Col1a1, Col6a6, and Col9a2. Overall, our study provides a full-scale DEG map regarding HFD-induced islet dysfunction, which was helpful to understand the underlying molecular mechanism of islet deterioration further.


Assuntos
Dieta Hiperlipídica , Células Secretoras de Glucagon , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Transcriptoma , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/metabolismo , Células Secretoras de Glucagon/metabolismo , RNA Mensageiro , Insulina/metabolismo
9.
Oxid Med Cell Longev ; 2023: 2713864, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36756299

RESUMO

Diabetic kidney disease (DKD) is a major microvascular complication of diabetes mellitus (DM) and is closely associated to programmed cell death. However, the complex mechanisms of necroptosis, an alternative cell death pathway, in DKD pathogenesis are yet to be elucidated. This study indicates that necroptosis is involved in DKD induced by high glucose (HG) both in vivo and in vitro. HG intervention led to the activation of RIPK1/RIPK3/MLKL signaling, resulting in renal tissue necroptosis and proinflammatory activation in streptozotocin/high-fat diet- (STZ/HFD-) induced diabetic mice and HG-induced normal rat kidney tubular cells (NRK-52E). We further found that in HG-induced NRK-52E cell, necroptosis might, at least partly, depend on the levels of reactive oxygen species (ROS). Meanwhile, ROS participated in necroptosis via a positive feedback loop involving the RIPK1/RIPK3 pathway. In addition, blocking RIPK1/RIPK3/MLKL signaling by necrostatin-1 (Nec-1), a key inhibitor of RIPK1 in the necroptosis pathway, or antioxidant N-acetylcysteine (NAC), an inhibitor of ROS generation, could effectively protect the kidney against HG-induced damage, decrease the release of proinflammatory cytokines, and rescue renal function in STZ/HFD-induced diabetic mice. Inhibition of RIPK1 effectively decreased the activation of RIPK1-kinase-/NF-κB-dependent inflammation. Collectively, we demonstrated that high glucose induced DKD via renal tubular epithelium necroptosis, and Nec-1 or NAC treatment downregulated the RIPK1/RIPK3/MLKL pathway and finally reduced necroptosis, oxidative stress, and inflammation. Thus, RIPK1 may be a therapeutic target for DKD.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Ratos , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Necroptose , Diabetes Mellitus Experimental/complicações , Rim/metabolismo , Inflamação , Glucose/toxicidade
10.
Aging (Albany NY) ; 15(22): 13384-13410, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38015723

RESUMO

A ketogenic diet (KD) and ß-hydroxybutyrate (ßOHB) have been widely reported as effective therapies for metabolic diseases. ß-Hydroxybutyrate dehydrogenase 1 (BDH1) is the rate-limiting enzyme in ketone metabolism. In this study, we examined the BDH1-mediated ßOHB metabolic pathway in the pathogenesis of diabetic kidney disease (DKD). We found that BDH1 is downregulated in the kidneys in DKD mouse models, patients with diabetes, and high glucose- or palmitic acid-induced human renal tubular epithelial (HK-2) cells. BDH1 overexpression or ßOHB treatment protects HK-2 cells from glucotoxicity and lipotoxicity by inhibiting reactive oxygen species overproduction. Mechanistically, BDH1-mediated ßOHB metabolism activates NRF2 by enhancing the metabolic flux of ßOHB-acetoacetate-succinate-fumarate. Moreover, in vivo studies showed that adeno-associated virus 9-mediated BDH1 renal expression successfully reverses fibrosis, inflammation, and apoptosis in the kidneys of C57 BKS db/db mice. Either ßOHB supplementation or KD feeding could elevate the renal expression of BDH1 and reverse the progression of DKD. Our results revealed a BDH1-mediated molecular mechanism in the pathogenesis of DKD and identified BDH1 as a potential therapeutic target for DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Humanos , Camundongos , Ácido 3-Hidroxibutírico/farmacologia , Antioxidantes/uso terapêutico , Nefropatias Diabéticas/metabolismo , Rim/patologia , Fator 2 Relacionado a NF-E2/genética , Hidroxibutirato Desidrogenase/metabolismo
11.
Cell Death Discov ; 8(1): 49, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115498

RESUMO

In 2020, a group of experts officially suggested metabolic dysfunction associated with fatty liver disease "MAFLD" as a more appropriate overarching term than NAFLD, indicating the key role of metabolism in fatty liver disease. Bdh1, as the rate-limiting enzyme of ketone metabolism, acts as an important metabolic regulator in liver. However, the role of Bdh1 in MAFLD is unclear. In this study, we used the transgenic db/db mice as a MAFLD mouse model and observed the downregulated expression of Bdh1 in fatty liver. In addition, expression of Bdh1 was also reduced by palmitic acid (PA) treatment in LO2 cells. Bdh1 knockdown led to ROS overproduction and ROS-induced inflammation and apoptosis in LO2 cells, while Bdh1 overexpression protected LO2 cells from lipotoxicity by inhibiting ROS overproduction. Mechanistically, Bdh1-mediated ßOHB metabolism inhibits ROS overproduction by activation of Nrf2 through enhancement of metabolic flux composed of ßOHB-AcAc-succinate-fumarate. Notably, adeno-associated virus (AAV)-mediated Bdh1 overexpression successfully reversed the hepatic function indexes, fibrosis, inflammation, and apoptosis in fatty livers from db/db mice. In conclusion, our study revealed a Bdh1-mediated molecular mechanism in pathogenesis of metabolic dysfunction related liver disease and identified Bdh1 as a novel potential therapeutic target for MAFLD.

12.
Front Med (Lausanne) ; 8: 759825, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35083231

RESUMO

Background: Maresin 1 plays a role in the regulation of inflammation and metabolic diseases in vivo. An increasing number of studies have reported that postmenopausal osteoporosis (PMOP) is associated with inflammation. However, the potential relationship between the serum Maresin 1 content and PMOP is unclear. Aims: 1) To evaluate the Maresin 1 content in postmenopausal women with osteopenia, osteoporosis, or without these conditions (normal group) and 2) to analyze the correlations between Maresin 1 concentrations and bone mineral density (BMD) and bone turnover markers. Methods: In this cross-sectional study, we measured serum Maresin 1 concentrations, serum biochemical parameters, markers of bone metabolism, and BMD of the femoral neck, lumbar spine, and hip in 141 postmenopausal women. Results: We found that serum Maresin 1 in the osteopenia (140.09 ± 30.54 pg/ml) and PMOP (124.68 ± 31.35 pg/ml) groups were significantly lower than those in the normal group (167.38 ± 24.85 pg/ml) (P < 0.05 and P < 0.001). Serum Maresin 1 levels were positively correlated with femoral neck, lumbar spine, and hip BMD (P < 0.001). Meanwhile, Maresin 1 concentrations were positively associated with 25-hydroxyvitamin D [25(OH)D] levels (P < 0.001), but negatively correlated with ß-CrossLaps of type 1 collagen containing cross-linked C-telopeptide (ß-CTX) (P = 0.002), procollagen type I amino-terminal propeptide (PINP) (P = 0.004), tartrate-resistant acid phosphatase 5b (TRAP-5b) (P = 0.005), and osteocalcin (OC) levels (P = 0.001). Multivariate logistic regression analysis showed that a decrease in Maresin 1 concentration was still associated with osteopenia (P = 0.035) or PMOP (P = 0.016). Maresin 1 levels had a maximum area under curve of 0.820 for osteopenia and 0.746 for PMOP (P < 0.001). Our results showed that the serum Maresin 1 levels were reduced in osteopenia and PMOP patients compared with that in normal subjects, and were the lowest in the PMOP subjects. The results suggest that Maresin 1 may serve as a new non-invasive diagnostic biomarker for PMOP.

13.
Adv Nutr ; 12(4): 1286-1304, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33751019

RESUMO

Elevated circulating trimethylamine N-oxide (TMAO) concentrations have been observed in patients with chronic kidney disease (CKD). We aimed to systematically estimate and quantify the association between TMAO concentrations and kidney function. The PubMed, EMBASE, Cochrane Library, Scopus, and Web of Science databases were systematically searched from 1995 to 1 June, 2020, for clinical studies on circulating TMAO concentrations and kidney function indicators. We used R software to conduct meta-analyses of the extracted data. A cumulative meta-analysis was applied to test whether health status affected the pooled effect value. Meta-regression and subgroup analyses were performed to identify possible sources of heterogeneity. Ultimately, we included a total of 32 eligible clinical studies involving 42,062 participants. In meta-analyses of continuous-outcome variables, advanced CKD was associated with a 67.9 µmol/L (95% CI: 52.7, 83.2; P < 0.01) increase in TMAO concentration, and subjects with high concentrations of TMAO had a 12.9 mL/(min·1.73 m2) (95% CI: -16.6, -9.14; P < 0.01) decrease in glomerular filtration rate (GFR). In meta-analyses of the correlations, TMAO was strongly inversely correlated with GFR [Fisher's z-transformed correlation coefficient (ZCOR): -0.45; 95% CI: -0.58, -0.32; P < 0.01] and positively associated with the urine albumin-to-creatinine ratio (UACR; ZCOR: 0.26; 95% CI: 0.08, 0.43; P < 0.01), serum creatinine (sCr; ZCOR: 0.43; 95% CI: 0.28, 0.58; P < 0.01), urine albumin excretion rate (UAER; ZCOR: 0.06; 95% CI: 0.04, 0.09; P < 0.01), blood urea (ZCOR: 0.50; 95% CI: 0.29, 0.72; P < 0.01), blood uric acid (ZCOR: 0.32; 95% CI: 0.25, 0.38; P < 0.01), and serum cystatin C (CysC; ZCOR: 0.47, 95% CI: 0.44, 0.51; P < 0.01). This is the first systematic review and meta-analysis to reveal a negative association between circulating TMAO concentrations and kidney function.


Assuntos
Microbioma Gastrointestinal , Humanos , Rim , Metilaminas , Fatores de Risco
14.
Oxid Med Cell Longev ; 2021: 3027954, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745415

RESUMO

Chronic high-dose alcohol consumption impairs bone remodeling, reduces bone mass, and increases the risk of osteoporosis and bone fracture. However, the mechanisms underlying alcohol-induced osteoporosis are yet to be elucidated. In this study, we showed that excess intake of ethyl alcohol (EtOH) resulted in osteopenia and osteoblast necroptosis in mice that led to necrotic lesions and reduced osteogenic differentiation in bone marrow mesenchymal stem cells (BMMSCs). We found that EtOH treatment led to the activation of the RIPK1/RIPK3/MLKL signaling, resulting in increased osteoblast necroptosis and decreased osteogenic differentiation and bone formation both in vivo and in vitro. We further discovered that excessive EtOH treatment-induced osteoblast necroptosis might partly depend on reactive oxygen species (ROS) generation; concomitantly, ROS contributed to necroptosis of osteoblasts through a positive feedback loop involving RIPK1/RIPK3. In addition, blocking of the RIPK1/RIPK3/MLKL signaling by necrostatin-1 (Nec-1), a key inhibitor of RIPK1 kinase in the necroptosis pathway, or antioxidant N-acetylcysteine (NAC), an inhibitor of ROS, could decrease the activation of osteoblast necroptosis and ameliorate alcohol-induced osteopenia both in vivo and in vitro. Collectively, we demonstrated that chronic high-dose alcohol consumption induced osteopenia via osteoblast necroptosis and revealed that RIPK1 kinase may be a therapeutic target for alcohol-induced osteopenia.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Doenças Ósseas Metabólicas/patologia , Necroptose , Osteoblastos/patologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
15.
Front Mol Biosci ; 7: 586450, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33102530

RESUMO

Fluorescently labeled proteins can improve the detection sensitivity and have been widely used in a variety of biological measurements. In single-molecule assays, site-specific labeling of proteins enables the visualization of molecular interactions, conformational changes in proteins, and enzymatic activity. In this study, based on a flexible linker in the Escherichia coli RecQ helicase, we established a scheme involving a combination of fluorophore labeling and sortase A ligation to allow site-specific labeling of the HRDC domain of RecQ with a single Cy5 fluorophore, without inletting extra fluorescent domain or peptide fragment. Using single-molecule fluorescence resonance energy transfer, we visualized that Cy5-labeled HRDC could directly interact with RecA domains and could bind to both the 3' and 5' ends of the overhang DNA dynamically in vitro for the first time. The present work not only reveals the functional mechanism of the HRDC domain, but also provides a feasible method for site-specific labeling of a domain with a single fluorophore used in single-molecule assays.

16.
Obesity (Silver Spring) ; 28(4): 793-802, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129005

RESUMO

OBJECTIVE: This study aimed to investigate whether antibiotic exposure during pregnancy and infancy was associated with childhood overweight or obesity. METHODS: PubMed, Embase, and Cochrane Library databases were searched from the inception date to April 18, 2019, to identify observational studies that investigated the association between antibiotic exposure during pregnancy and infancy and childhood overweight or obesity. After study selection and data extraction, the meta-analysis was conducted using Stata software version 12.0 (StataCorp LP, College Station, Texas). The evaluation of the methodological quality was carried out by AMSTAR 2 (Bruyère Research Institute, Ottawa, Ontario, Canada). RESULTS: A total of 23 observational studies involving 1,253,035 participants were included. The meta-analysis showed that prenatal exposure to antibiotics was not significantly associated with childhood overweight or obesity, whereas an increased risk of overweight or obesity was seen in subgroup analysis of the second trimester (risk ratio = 1.13; 95% CI: 1.06-1.22; P = 0.001). In contrast, antibiotic exposure during infancy could increase the risk of childhood overweight or obesity (risk ratio = 1.14; 95% CI: 1.06-1.23; P = 0.001). CONCLUSIONS: This meta-analysis found that antibiotic exposure during the second trimester and infancy could increase the risk of childhood overweight or obesity.


Assuntos
Antibacterianos/uso terapêutico , Obesidade Infantil/etiologia , Adulto , Antibacterianos/farmacologia , Criança , Feminino , Humanos , Lactente , Exposição Materna , Gravidez , Adulto Jovem
17.
Endocrine ; 67(2): 294-304, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31900793

RESUMO

PURPOSE: To evaluate the efficacy and safety of combination therapy with sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists in the treatment of type 2 diabetes mellitus (T2DM) or obese adults. METHODS: A meta-analysis was conducted of trials by searching in PubMed, Embase, CENTRAL, Web of Science, and Scopus. RESULTS: A total of five randomized controlled trials (RCTs) and six nonrandomized controlled trials (NCTs) enrolled 1604 participants were identified for meta-analysis. Compared with control/placebo, the combination therapy group had significantly reduced fasting plasma glucose level and 2 h postprandial glucose by 1.28 mmol/L (95% confidence interval [CI]: -1.39, -1.16; p < 0.001) and 1.34 mmol/L (95% CI: -1.47, -1.21; p < 0.001); glycosylated hemoglobin (HbA1c) by 1.32% (95% CI: -1.43, -1.20; p < 0.001); body weight by 0.93 kg (95% CI: -1.04, -0.83; p < 0.001), and systolic blood pressure (SBP) by 1.05 mmHg (95% CI: -1.17, -0.93; p < 0.001). The incidence of genital mycotic infections and urinary infections did not significantly differ from those in the control group, with relative risks (RRs) of 1.67 (95% CI: 0.85, 3.27; p = 0.651) and 1.25 (95% CI: 0.73, 2.15; p = 0.905), respectively. A decreased incidence of cardiovascular events was seen in the combination therapy group (RR = 0.19; 95% CI: 0.04, 0.96; p = 0.403), while an incidence of hypoglycemia was reported (RR = 2.22; 95% CI: 1.20, 4.10; p = 0.71). CONCLUSIONS: SGLT2 inhibitors and GLP-1 agonists combination treatment improved glycemic control, reduced body weight, and decreased SBP without an increase in total adverse events or genital and urinary infections in patients with T2DM or obesity.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Adulto , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Hipoglicemiantes/efeitos adversos , Obesidade/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
18.
FEBS J ; 284(23): 4051-4065, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28986969

RESUMO

Non-canonical four-stranded G-quadruplex (G4) DNA structures can form in G-rich sequences that are widely distributed throughout the genome. The presence of G4 structures can impair DNA replication by hindering the progress of replicative polymerases (Pols), and failure to resolve these structures can lead to genetic instability. In the present study, we combined different approaches to address the question of whether and how Escherichia coli Pol I resolves G4 obstacles during DNA replication and/or repair. We found that E. coli Pol I-catalyzed DNA synthesis could be arrested by G4 structures at low protein concentrations and the degree of inhibition was strongly dependent on the stability of the G4 structures. Interestingly, at high protein concentrations, E. coli Pol I was able to overcome some kinds of G4 obstacles without the involvement of other molecules and could achieve complete replication of G4 DNA. Mechanistic studies suggested that multiple Pol I proteins might be implicated in G4 unfolding, and the disruption of G4 structures requires energy derived from dNTP hydrolysis. The present work not only reveals an unrealized function of E. coli Pol I, but also presents a possible mechanism by which G4 structures can be resolved during DNA replication and/or repair in E. coli.


Assuntos
DNA Polimerase I/metabolismo , Replicação do DNA , Proteínas de Escherichia coli/metabolismo , Quadruplex G , Sequência de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Modelos Genéticos , Modelos Moleculares , Conformação de Ácido Nucleico
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