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2.
PLoS Pathog ; 20(6): e1012311, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38885273

RESUMO

The majority of rod-shaped and some filamentous plant viruses encode a cysteine-rich protein (CRP) that functions in viral virulence; however, the roles of these CRPs in viral infection remain largely unknown. Here, we used barley stripe mosaic virus (BSMV) as a model to investigate the essential role of its CRP in virus morphogenesis. The CRP protein γb directly interacts with BSMV coat protein (CP), the mutations either on the His-85 site in γb predicted to generate a potential CCCH motif or on the His-13 site in CP exposed to the surface of the virions abolish the zinc-binding activity and their interaction. Immunogold-labeling assays show that γb binds to the surface of rod-shaped BSMV virions in a Zn2+-dependent manner, which enhances the RNA binding activity of CP and facilitates virion assembly and stability, suggesting that the Zn2+-dependent physical association of γb with the virion is crucial for BSMV morphogenesis. Intriguingly, the tightly binding of diverse CRPs to their rod-shaped virions is a general feature employed by the members in the families Virgaviridae (excluding the genus Tobamovirus) and Benyviridae. Together, these results reveal a hitherto unknown role of CRPs in the assembly and stability of virus particles, and expand our understanding of the molecular mechanism underlying virus morphogenesis.


Assuntos
Vírion , Zinco , Zinco/metabolismo , Vírion/metabolismo , Proteínas do Capsídeo/metabolismo , Montagem de Vírus/fisiologia , Vírus de Plantas/metabolismo , Vírus de Plantas/fisiologia , Doenças das Plantas/virologia , Cisteína/metabolismo , Proteínas Virais/metabolismo , Morfogênese
3.
Eur J Radiol ; 176: 111502, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759544

RESUMO

OBJECTIVE: To summary radiating blood flow signals and evaluate their diagnostic value in differentiating benign and malignant thyroid nodules. MATERIALS AND METHODS: We retrospectively recruited consecutive patients undergoing US at 4 hospitals from 2018 to 2022. In a training dataset, the correlations of US features with malignant thyroid nodules were assessed by multivariate logistic analysis. Multivariate logistic regression models involving the ACR TI-RADS score, radiating blood flow signals and their combination were built and validated internally and externally. The AUC with 95% asymptotic normal confidence interval as well as sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) with 95% exact binomial confidence intervals were calculated. RESULTS: Among 2475 patients (1818 women, age: 42.47 ± 11.57; 657 men, age: 42.16 ± 11.69), there were 3187 nodules (2342 malignant nodules and 845 benign nodules). Radiating blood flow signals were an independent risk factor for diagnosing thyroid carcinoma. In the training set, the AUC of the model using the combination of radiating blood flow signals and the ACR TI-RADS score (0.95 95 % CI: [0.94, 0.97]; P < 0.001) was significantly higher than that of the ACR TI-RADS model (0.91 [0.89, 0.93]). In the two internal validation sets and the external validation set, the AUCs of the combination model were 0.97 [0.96, 0.98], 0.92 [0.88, 0.96], and 0.91 [0.86, 0.95], respectively, and were all significantly higher than that of the ACR TI-RADS score (0.92 [0.90, 0.95], 0.86 [0.81, 0.91], 0.84 [0.79, 0.89]; P < 0.001). CONCLUSION: Radiating blood flow is a new US feature of thyroid carcinomas that can significantly improve the diagnostic performance vs. the ACR TI-RADS score.


Assuntos
Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide , Ultrassonografia , Humanos , Masculino , Feminino , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Estudos Retrospectivos , Ultrassonografia/métodos , Diagnóstico Diferencial , Pessoa de Meia-Idade , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/irrigação sanguínea
4.
ChemMedChem ; 19(14): e202400124, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38632079

RESUMO

Cyclotides are cyclic peptides that are promising scaffolds for the design of drug candidates and chemical tools. However, despite there being hundreds of reported cyclotides, drug design studies have commonly focussed on a select few prototypic examples. Here, we explored whether ancestral sequence reconstruction could be used to generate new cyclotides for further optimization. We show that the reconstructed 'pseudo-ancestral' sequences, named Ancy-m (for the ancestral cyclotide of the Möbius sub-family) and Ancy-b (for the bracelet sub-family), have well-defined structures like their extant members, comprising the core structural feature of a cyclic cystine knot. This motif underpins efforts to re-engineer cyclotides for agrochemical and therapeutic applications. We further show that the reconstructed sequences are resistant to temperatures approaching boiling, bind to phosphatidyl-ethanolamine lipid bilayers at micromolar affinity, and inhibit the growth of insect cells at inhibitory concentrations in the micromolar range. Interestingly, the Ancy-b cyclotide had a higher oxidative folding yield than its comparator cyclotide cyO2, which belongs to the bracelet cyclotide subfamily known to be notoriously difficult to fold. Overall, this study provides new cyclotide sequences not yet found naturally that could be valuable starting points for the understanding of cyclotide evolution and for further optimization as drug leads.


Assuntos
Ciclotídeos , Ciclotídeos/química , Ciclotídeos/farmacologia , Animais , Relação Estrutura-Atividade , Bicamadas Lipídicas/química , Sequência de Aminoácidos , Relação Dose-Resposta a Droga , Fosfatidiletanolaminas/química
5.
Poult Sci ; 103(6): 103734, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636201

RESUMO

Dietary supplementation with bioactive substances that can regulate lipid metabolism is an effective approach for reducing excessive fat deposition in chickens. Genistein (GEN) has the potential to alleviate fat deposition; however, the underlying mechanism of GEN's fat-reduction action in chickens remains unclear. Therefore, the present study aimed to explore the underlying mechanism of GEN on the reduction of fat deposition from a novel perspective: intercellular transmission of adipokine between adipocytes and hepatocytes. The findings showed that GEN enhanced the secretion of adiponectin (APN) in chicken adipocytes, and the enhancement effect of GEN was completely blocked when the cells were pretreated with inhibitors targeting estrogen receptor ß (ERß) or proliferator-activated receptor γ (PPARγ) signals, respectively. Furthermore, the results demonstrated that both co-treatment with GEN and APN or treatment with the medium supernatant (Med SUP) derived from chicken adipocytes treated with GEN significantly decreased the content of triglyceride and increased the protein levels of ERß, Sirtuin 1 (SIRT1) and phosphor-AMP-activated protein kinase (p-AMPK) in chicken hepatocytes compared to the cells treated with GEN or APN alone. Moreover, the increase in the protein levels of SIRT1 and p-AMPK induced by GEN and APN co-treatment or Med SUP treatment were blocked in chicken hepatocytes pretreated with the inhibitor of ERß signals. Importantly, the up-regulatory effect of GEN and APN co-treatment or Med SUP treatment on the protein level of p-AMPK was also blocked in chicken hepatocytes pretreated with a SIRT1 inhibitor; however, the increase in the protein level of SIRT1 induced by GEN and APN co-treatment or Med SUP treatment was not reversed when the hepatocytes were pretreated with an AMPK inhibitor. In conclusion, the present study demonstrated that GEN enhanced APN secretion by activating the ERß-Erk-PPARγ signaling pathway in chicken adipocytes. Subsequently, adipocyte-derived APN synergized with GEN to activate the ERß-mediated SIRT1-AMPK signaling pathway in chicken hepatocytes, ultimately reducing fat deposition. These findings provide substantial evidence from a novel perspective, supporting the potential use of GEN as a dietary supplement to prevent excessive fat deposition in poultry.


Assuntos
Adiponectina , Galinhas , Receptor beta de Estrogênio , Genisteína , Hepatócitos , Transdução de Sinais , Sirtuína 1 , Animais , Genisteína/farmacologia , Genisteína/administração & dosagem , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Sirtuína 1/metabolismo , Receptor beta de Estrogênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adiponectina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Aviárias/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo/efeitos dos fármacos
6.
Cell Death Dis ; 15(2): 158, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383528

RESUMO

Chemotherapy is a primary treatment for esophageal squamous cell carcinoma (ESCC). Resistance to chemotherapeutic drugs is an important hurdle to effective treatment. Understanding the mechanisms underlying chemotherapy resistance in ESCC is an unmet medical need to improve the survival of ESCC. Herein, we demonstrate that ferroptosis triggered by inhibiting high mobility group AT-hook 1 (HMGA1) may provide a novel opportunity to gain an effective therapeutic strategy against chemoresistance in ESCC. HMGA1 is upregulated in ESCC and works as a key driver for cisplatin (DDP) resistance in ESCC by repressing ferroptosis. Inhibition of HMGA1 enhances the sensitivity of ESCC to ferroptosis. With a transcriptome analysis and following-up assays, we demonstrated that HMGA1 upregulates the expression of solute carrier family 7 member 11 (SLC7A11), a key transporter maintaining intracellular glutathione homeostasis and inhibiting the accumulation of malondialdehyde (MDA), thereby suppressing cell ferroptosis. HMGA1 acts as a chromatin remodeling factor promoting the binding of activating transcription factor 4 (ATF4) to the promoter of SLC7A11, and hence enhancing the transcription of SLC7A11 and maintaining the redox balance. We characterized that the enhanced chemosensitivity of ESCC is primarily attributed to the increased susceptibility of ferroptosis resulting from the depletion of HMGA1. Moreover, we utilized syngeneic allograft tumor models and genetically engineered mice of HMGA1 to induce ESCC and validated that depletion of HMGA1 promotes ferroptosis and restores the sensitivity of ESCC to DDP, and hence enhances the therapeutic efficacy. Our finding uncovers a critical role of HMGA1 in the repression of ferroptosis and thus in the establishment of DDP resistance in ESCC, highlighting HMGA1-based rewiring strategies as potential approaches to overcome ESCC chemotherapy resistance. Schematic depicting that HMGA1 maintains intracellular redox homeostasis against ferroptosis by assisting ATF4 to activate SLC7A11 transcription, resulting in ESCC resistance to chemotherapy.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Ferroptose , Animais , Camundongos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proteína HMGA1a/genética , Resistencia a Medicamentos Antineoplásicos/genética , Ferroptose/genética , Proteína HMGA1b , Linhagem Celular Tumoral
7.
J Biol Chem ; 300(3): 105661, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246352

RESUMO

Nonalcoholic fatty liver disease (NAFLD), especially nonalcoholic steatohepatitis (NASH), has emerged as a prevalent cause of liver cirrhosis and hepatocellular carcinoma, posing severe public health challenges worldwide. The incidence of NASH is highly correlated with an increased prevalence of obesity, insulin resistance, diabetes, and other metabolic diseases. Currently, no approved drugs specifically targeted for the therapies of NASH partially due to the unclear pathophysiological mechanisms. G protein-coupled estrogen receptor 1 (GPER1) is a membrane estrogen receptor involved in the development of metabolic diseases such as obesity and diabetes. However, the function of GPER1 in NAFLD/NASH progression remains unknown. Here, we show that GPER1 exerts a beneficial role in insulin resistance, hepatic lipid accumulation, oxidative stress, or inflammation in vivo and in vitro. In particular, we observed that the lipid accumulation, inflammatory response, fibrosis, or insulin resistance in mouse NAFLD/NASH models were exacerbated by hepatocyte-specific GPER1 knockout but obviously mitigated by hepatic GPER1 activation in female and male mice. Mechanistically, hepatic GPER1 activates AMP-activated protein kinase signaling by inducing cyclic AMP release, thereby exerting its protective effect. These data suggest that GPER1 may be a promising therapeutic target for NASH.


Assuntos
Diabetes Mellitus , Resistência à Insulina , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Feminino , Masculino , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Receptor alfa de Estrogênio/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Lipídeos/farmacologia , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Camundongos Endogâmicos C57BL , Estrogênios/deficiência , Estrogênios/metabolismo , Dieta Hiperlipídica
8.
Front Med (Lausanne) ; 10: 1169776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37575988

RESUMO

Persistent idiopathic macular hole (PIMH), the occurrence of idiopathic macular holes that have failed to close after standard pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling, has become a global health threat to the aging population. Because postoperative anatomic closure or restoration of visual acuity is more difficult to achieve in PIMH, surgical approaches that would yield the best outcomes remain to be elucidated. On paper, extended ILM peeling combined with silicone oil (SiO) tamponade is believed to be a feasible option for excellent macular hole closure. However, no studies on this combined treatment for PIMH is compared with simple air tamponade have been conducted. Thus, in this retrospective case series, we used spectral-domain optical coherence tomography (SD-OCT) and other technologies to investigate real-world evidence for the anatomical and functional outcomes of revisional PPV with either SiO or air tamponade for failed primary idiopathic macular hole surgery. We included the records of 76 patients with PIMH who had SD-OCT examinations and best-corrected visual acuity (BCVA). Regression analysis was performed to find factors affecting PIMH fracture closure. Seventy-six participants were allocated to a SiO group (n = 21, with an extended ILM peeling and SiO tamponade) or an air group (n = 55, with extended ILM peeling and air tamponade). Anatomical success was achieved in 18 (85.7%) and 40 (72.7%) eyes in the SiO and air groups, respectively (p = 0.37). BCVA was significantly improved in both subgroups of closed PIMH (SiO group: p = 0.041; air group: p < 0.001). Minimum linear diameter (MLD) was closely related to the closure rate (OR, 1.0; 95% CI (0.985-0.999); p = 0.03). MLD = 650 µm seemed like a cut-off point for closure rate (MLD ≤ 650 µm vs. MLD > 650 µm; 88.4% vs. 52%, p = 0.002). In conclusion, we demonstrated that extended ILM peeling combined with SiO or air tamponade is effective in PIMH treatment. Moreover, though not statistically significant herein, the anatomic closure rate was better for silicone-operated eyes than for air-operated eyes. MLD is the best predictor of PIMH closure; MLD ≤ 650 µm could achieve a significantly higher closure rate.

9.
JAMA Ophthalmol ; 141(8): e231065, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589965

RESUMO

This case report discusses a diagnosis of iris cavernous hemangioma in a woman aged 63 years who presented with recurrent pain, redness, and hazy vision in her left eye.


Assuntos
Oftalmopatias , Hemangioma , Humanos
10.
Int J Ophthalmol ; 16(7): 1110-1116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465504

RESUMO

AIM: To determine the incidence and predictive factors for epiretinal membrane (ERM) formation in eyes with complicated primary rhegmatogenous retinal detachment (RRD) tamponaded with silicone oil (SO). METHODS: This retrospective case-control study included 141 consecutive patients with (51 eyes) and without (90 eyes) ERM formation after primary pars plana vitrectomy (PPV) and SO tamponade for complicated RRD. The risk factors for ERM were assessed using logistic regression analysis. RESULTS: The prevalence of postoperative ERM was 36.2% (51/141). Multivariate logistic regression analysis showed that the risk factors for ERM in SO-tamponaded eyes included preoperative proliferative vitreoretinopathy [PVR; odds ratio (OR), 2.578; 95% confidence interval (CI) 1.580-4.205, P<0.001], preoperative choroidal detachment (OR, 4.454; 95%CI 1.369-14.498, P=0.013), and photocoagulation energy (OR, 2.700; 95%CI 1.047-6.962, P=0.040). The duration of the preoperative symptoms, intraocular SO tamponade time, giant retinal tear, preoperative vitreous hemorrhage, preoperative best-corrected visual acuity, number of breaks, quadrants of RRD, axial length, and photocoagulation points were not predictive factors for ERM formation. CONCLUSION: Preoperative PVR, choroidal detachment, and photocoagulation energy are risk factors of ERM formation after complicated RRD repair. Better ophthalmic care as well as patient education are necessary for such patients with risk factors.

11.
Fish Shellfish Immunol ; 139: 108906, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37348686

RESUMO

Synthetic phenolic antioxidants (SPAs) are an environmental concern due to their persistence nature and bioaccumulation. However, the hepatoxicity and mechanisms of SPAs in aquatic organisms remain poorly understood. In this study, grass carp were exposed to two representative SPAs (BHA and BHT) at environmentally relevant levels (0.1 µM) for 30 days. We observed that BHA and BHT exposure significantly increased the levels of serum aminotransferase (ALT) and aspartate aminotransferase (AST) in grass carp, accompanied by mild inflammatory cell infiltration and irregularity in the shape of hepatocytes. Dihydro ethylenediamine staining showed that BHA and BHT exposure resulted in elevated levels of superoxide levels, accompanied by increased antioxidant enzyme activities (T-AOC, SOD, CAT, GSH-PX) and MDA levels, which is suggestive of oxidative stress responses in the liver of grass carp. Besides, BHA and BHT could dock into the pocket of phosphatidylinositol 3-kinases (PI3K) and thereby inhibiting PI3K/mammalian target of rapamycin (mTOR)/protein kinase B (AKT) signaling cascades. Meanwhile, our results clarified that BHA and BHT could promote autophagosome production and increase the expression of key autophagy proteins, likely due to inhibition of PI3K/mTOR/AKT signaling pathway. Moreover, BHA and BHT could induce apoptotic process by upregulating the expression of Bax, Caspase3 and Caspase8 and downregulating Bcl2 expression. Notably, BHT exhibited more hepatoxicity on the indicators of the apoptosis and oxidative stress than BHA. In summary, our findings demonstrated that BHA and BHT exposure could induce liver damage induced via regulating ROS/PI3K-mediated autophagic hyperactivation, which is a crucial step in triggering hepatocyte death. This study provides novel insight into the potential mechanisms underlying liver damage caused by BHA and BHT in aquatic organisms, and offers a new theoretical basis for ecological risk assessment of SPAs.


Assuntos
Antioxidantes , Carpas , Animais , Antioxidantes/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sirolimo , Carpas/metabolismo , Fenóis , Apoptose , Autofagia , Serina-Treonina Quinases TOR/metabolismo , Mamíferos/metabolismo
12.
Water Res ; 238: 119995, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37156101

RESUMO

Electroactivity is an important parameter to assess the ability of the extracellular polymeric substance (EPS) of microorganisms to participate in extracellular respiration. Many reports have found that the electroactivity of microbial sludge could be enhanced with electrical stimulation, but the reason remains unclear. The results of this study showed that the current generation of the three microbial electrolysis cells increased by 1.27-1.76 times during 49 days of electrical stimulation, but the typical electroactive microorganisms were not enriched. Meanwhile, the capacitance and conductivity of EPS of sludge after the electrical stimulation increased by 1.32-1.83 times and 1.27-1.32 times, respectively. In-situ FTIR analysis indicated that the electrical stimulation could lead to the polarization of amide groups in the protein, likely affecting the protein structure related to the electroactivity. Accordingly, the dipole moment of the α-helix peptide of protein of sludge increased from 220 D to 280 D after the electrical stimulation, which was conducive to electron transfer in the α-helix peptide. Moreover, the vertical ionization potential and ELUMO-EHOMO energy gap of the C-terminal in the α-helix peptide decreased from 4.43 eV to 4.10 eV and 0.41 eV to 0.24 eV, respectively, which indicated that the α-helix was easier to serve as the electron transfer site of electron hopping. These results meant that the enhancement of the dipole moment of the α-helix peptide unchoked the electron transfer chain of the protein, which was the main reason for the increased electroactivity of EPS protein.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Matriz Extracelular de Substâncias Poliméricas/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Esgotos/química , Conformação Proteica em alfa-Hélice , Proteínas/análise , Peptídeos/análise , Peptídeos/metabolismo , Estimulação Elétrica
13.
Brain Behav Immun ; 109: 308-320, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36754246

RESUMO

Pain is one of the most severe complications affecting the quality of life of cancer patients. Although substantial progress has been made in the diagnosis and treatment of cancer, the neurobiological mechanism of cancer pain is still unclear. In the present study, we identified the critical role of CXC chemokine 2 (CXCL2), released by Schwann cells after being activated by cancer cells, in maintaining cancer-induced macrophage infiltration and the resulting mechanical hypersensitivity and persistent spontaneous nociception. In vitro, Schwann cells cocultured with breast cancer cells exhibited a significant increase in CXCL2 expression; in addition, conditioned medium from Schwann cells activated by breast cancer cells had a similar effect to recombinant CXCL2 in terms of inducing macrophage migration. Targeting CXCL2 signaling by both CXC chemokine receptor 2 (CXCR2) antagonist pharmacological blockade and anti-CXCL2 mAb immunological blockade robustly prevented conditioned medium-induced macrophage migration. In vivo, both application of recombinant CXCL2 and perineural breast cancer cell implantation resulted in mechanical hypersensitivity and persistent spontaneous nociception in mice, along with increased macrophage infiltration into the sciatic nerves. Similar to the in vitro results, inhibition of CXCL2/CXCR2 signaling or conditional knockdown of CXCL2 in sciatic nerve Schwann cells effectively attenuated breast cancer cell-induced mechanical hypersensitivity, persistent spontaneous nociception, and macrophage recruitment in the sciatic nerve. Mechanistically, we found that redox effector factor-1 (Ref-1) secreted by breast cancer cells activated hypoxia inducible factor-1α (HIF-1α) expression and inhibited reactive oxygen species (ROS) production in Schwann cells, ultimately inducing CXCL2 expression in Schwann cells. In brief, the present study expands new insights into cancer pain mechanisms from promising animal models to provide new strategies for the control of cancer pain.


Assuntos
Dor do Câncer , Neoplasias , Camundongos , Animais , Quimiocinas CXC/metabolismo , Dor do Câncer/metabolismo , Meios de Cultivo Condicionados/farmacologia , Meios de Cultivo Condicionados/metabolismo , Qualidade de Vida , Macrófagos/metabolismo , Fatores Imunológicos , Células de Schwann/metabolismo , Neoplasias/metabolismo
14.
Mol Immunol ; 155: 110-123, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36773597

RESUMO

Fatty liver hemorrhage syndrome (FLHS) seriously threatens the health and performance of laying hens, and the occurrence and development of FLHS are closely related to oxidative damage and inflammation; thus, diets supplemental with activated substances to relive the oxidative stress and inflammation maybe effectively control the occurrences of FLHS. Dehydroepiandrosterone (DHEA) has beneficial effects in fat-reduction, anti-oxidation and anti-inflammation, and it was widely applied to alleviate multiple metabolic-related diseases; however, there are few reports on whether DHEA can prevent against metabolic-related diseases by modulating oxidative stress and inflammation, especially FLHS in laying hens. Herein, present study aimed to investigate the regulatory actions and potential molecular mechanism of DHEA on inflammation and oxidative stress triggered by oleic acid (OA)-stimulation in primary chicken hepatocytes and chicken hepatocellular carcinoma cell line (LMH). The results showed that DHEA significantly alleviated oxidative stress challenged by OA-stimulation via activation of AMP-activated protein kinase (AMPK)-nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling pathway in hepatocytes, which led to relieving effect of DHEA on inflammatory by inhibiting mitogen-activated protein kinases (MAPKs) and nuclear factor κB (NF-κB) signaling pathways. Mechanistically, we found that the activation of AMPK-Nrf2 signaling pathway by DHEA treatment was mediated by G-protein coupled estrogen receptor (GPR30/GPER) in OA-stimulated hepatocytes. Further investigation found that DHEA activated the GPR30-mediated AMPK-Nrf2 signaling pathways to increase antioxidant capacity and inhibit mitochondrial reactive oxygen species (ROS) overproduction, which thereby inhibiting the activation of ROS-induced MAPK and NF-κB signaling pathways in OA-stimulated hepatocytes. Overall, these data demonstrated that DHEA attenuates the oxidative stress and inflammation triggered by OA-stimulation, and these beneficial effects of DHEA are achieved by activating the GPR30-mediated AMPK-Nrf2 signaling to prevent the impairment of mitochondrial function, and thereby inhibiting the activation of ROS-induced MAPK and NF-κB signaling pathways in hepatocytes. These results revealed the effects and mechanisms of DHEA on oxidative stress and inflammation, and also provide substantial information to support it as a potential nutritional supplement in preventing the occurrences of FLHS in laying hens and other metabolic-related diseases in animals and humans.


Assuntos
Proteínas Quinases Ativadas por AMP , Ácido Oleico , Humanos , Animais , Feminino , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Ácido Oleico/efeitos adversos , Ácido Oleico/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Galinhas , Estresse Oxidativo , Hepatócitos/metabolismo , Inflamação/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Desidroepiandrosterona/farmacologia
15.
Life Sci ; 312: 121259, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463943

RESUMO

Excessive fat accumulation in broiler chickens would seriously threaten the poultry industry. It leads to lower feed conversion rate and worse meat quality. Even worse, it harms the consumers' health due to the intake of high-fat chicken products. Dietary supplements with bioactive ingredients have been considered an effective way to solve this problem. Genistein is the primary phytoestrogen in soybean. Its fat-reduction effect has been reported, but the molecular mechanism is unclear. The present study found that genistein reduced lipid droplets accumulation by regulating lipid metabolism-related factors expression in chicken hepatocytes. The research showed that genistein significantly increased phosphor (p)-AMP-activated protein kinase (p-AMPK) and Sirtuin 1 (SIRT1) protein expressions. The effect of genistein on reducing lipid droplets accumulation and upregulating p-AMPK protein level was blocked entirely when pretreated with SIRT1 inhibitor. These results implied that SIRT1 is required to activate AMPK. Furthermore, genistein treatment significantly upregulated the SIRT1 protein level when pretreated with AMPK inhibitor. We demonstrated that the activation of estrogen receptor ß-Forkhead box O1-Nicotinamide phosphoribosyl transferase (ERß-FOXO1-Nampt) signaling pathway upregulated the NAD+ concentration in hepatocytes, and activated SIRT1 ultimately. In summary, we demonstrated that genistein suppressed lipid droplets accumulation in chicken hepatocytes by activating SIRT1-AMPK. The SIRT1-AMPK signaling pathway was mediated by ERß-FOXO1-Nampt. These findings increase our understanding of the mechanisms of genistein on fat reduction, and provide compelling evidence for it as a nutritional supplement to prevent excessive fat deposition and lipid metabolism-related diseases in animals and even humans.


Assuntos
Proteínas Quinases Ativadas por AMP , Sirtuína 1 , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Galinhas/metabolismo , Receptor beta de Estrogênio/metabolismo , Proteína Forkhead Box O1/metabolismo , Genisteína/farmacologia , Genisteína/metabolismo , Hepatócitos/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo
16.
Front Cell Neurosci ; 16: 1005399, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467604

RESUMO

Spinal cord injury (SCI) is a serious neurological trauma that is challenging to treat. After SCI, many neurons in the injured area die due to necrosis or apoptosis, and astrocytes, oligodendrocytes, microglia and other non-neuronal cells become dysfunctional, hindering the repair of the injured spinal cord. Corrective surgery and biological, physical and pharmacological therapies are commonly used treatment modalities for SCI; however, no current therapeutic strategies can achieve complete recovery. Somatic cell reprogramming is a promising technology that has gradually become a feasible therapeutic approach for repairing the injured spinal cord. This revolutionary technology can reprogram fibroblasts, astrocytes, NG2 cells and neural progenitor cells into neurons or oligodendrocytes for spinal cord repair. In this review, we provide an overview of the transcription factors, genes, microRNAs (miRNAs), small molecules and combinations of these factors that can mediate somatic cell reprogramming to repair the injured spinal cord. Although many challenges and questions related to this technique remain, we believe that the beneficial effect of somatic cell reprogramming provides new ideas for achieving functional recovery after SCI and a direction for the development of treatments for SCI.

17.
Life Sci ; 308: 120926, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36058264

RESUMO

Fatty liver hemorrhagic syndrome (FLHS) seriously threatens the layer industry due to it can cause a sudden decline in egg production and acute death, and dietary supplement with bioactive substance is considered an effective way to prevent the FLHS occurrence. Dehydroepiandrosterone (DHEA) is a popular dietary supplement and it possesses anti-oxidative and anti-inflammatory functions; however, the effect and underlying mechanism about DHEA in protecting against the occurrence and development of FLHS remain elucidated. The current results showed that DHEA relieved HELP-induced decrease of egg productivity and liver injury in laying hens. Meanwhile, DHEA markedly enhanced the antioxidant capacity and then alleviated oxidative stress via activation of nuclear factor (erythroid-derived 2)-like 2 (NRF-2) signal in laying hens fed with HELP diets. In addition, DHEA significantly alleviated HELP-stimulated systemic inflammatory response by suppressing the overproduction of hepatic pro-inflammatory factors in laying hens, and further found this beneficial effect was achieved by blocking the activation of NF-κB pathway. Furthermore, we found that DHEA promoted the AMP-activated protein kinase α (AMPKα) activation and increased the G-protein-coupled estrogen receptor (GPER) expression level in laying hens fed with HELP diets. In summary, our data demonstrated that DHEA attenuates oxidative stress and inflammation through the activation of GPER-AMPK signal axis in laying hens fed with HELP diets. These results might facilitate an understanding of the benefits and mechanism of DHEA on the development of FLHS, and provide sufficient data to support it as a dietary supplement to control the FLHS-related metabolic diseases in chickens.


Assuntos
Fígado Gorduroso , Doenças das Aves Domésticas , Proteínas Quinases Ativadas por AMP/metabolismo , Anormalidades Múltiplas , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Galinhas/metabolismo , Anormalidades Craniofaciais , Desidroepiandrosterona/farmacologia , Dieta , Dieta com Restrição de Proteínas , Estrogênios , Fígado Gorduroso/metabolismo , Feminino , Proteínas de Ligação ao GTP/metabolismo , Transtornos do Crescimento , Comunicação Interventricular , Hemorragia/etiologia , NF-kappa B/metabolismo , Estresse Oxidativo , Doenças das Aves Domésticas/etiologia , Doenças das Aves Domésticas/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais
18.
EMBO J ; 41(13): e110060, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35642376

RESUMO

Viral replication and movement are intimately linked; however, the molecular mechanisms regulating the transition between replication and subsequent movement remain largely unknown. We previously demonstrated that the Barley stripe mosaic virus (BSMV) γb protein promotes viral replication and movement by interacting with the αa replicase and TGB1 movement proteins. Here, we found that γb is palmitoylated at Cys-10, Cys-19, and Cys-60 in Nicotiana benthamiana, which supports BSMV infection. Intriguingly, non-palmitoylated γb is anchored to chloroplast replication sites and enhances BSMV replication, whereas palmitoylated γb protein recruits TGB1 to the chloroplasts and forms viral replication-movement intermediate complexes. At the late stages of replication, γb interacts with NbPAT15 and NbPAT21 and is palmitoylated at the chloroplast periphery, thereby shifting viral replication to intracellular and intercellular movement. We also show that palmitoylated γb promotes virus cell-to-cell movement by interacting with NbREM1 to inhibit callose deposition at the plasmodesmata. Altogether, our experiments reveal a model whereby palmitoylation of γb directs a dynamic switch between BSMV replication and movement events during infection.


Assuntos
Lipoilação , Vírus de Plantas , Nicotiana/metabolismo , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
19.
Life Sci ; 303: 120676, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35640778

RESUMO

Genistein, the most abundance of phytoestrogens in soybeans, has beneficial effects in regulating metabolism-related disease; however, there is few available literatures about whether genistein regulates glucose metabolism that in turn affects the lipid accumulation in animals or humans. The current study showed that genistein promoted glucose uptake by enhancing glucose transporter-2 (GLUT2) protein level; and it also increased the activity of phosphofructokinase-1 (PFK) and pyruvate dehydrogenase (PDH), and the mRNA level of succinate dehydrogenase (SDH) both in broiler chickens or hepatocytes. Moreover, genistein obviously increased the p-LKB1 and p-AMPKα protein levels both in vivo and in vitro. Furthermore, the enhancement of genistein on glucose uptake and catabolism were reversed in hepatocytes pre-treated with AMPK inhibitor Compound C, and the increasing of genistein on the p-LKB1 and p-AMPKα protein levels were also reversed in hepatocytes pre-treated with PKA inhibitor H89. Importantly, the results showed that genistein simultaneously increased the estrogen receptor ß (ERß) and G protein-coupled estrogen receptor (GPER) protein levels, but the elevation effect of genistein on cAMP content was completely reversed in hepatocytes pre-treated with GPER antagonist G15, rather than ERß inhibitor PHTPP. Meanwhile, the increasing of p-LKB1 and p-AMPKα protein levels induced by genistein were also reversed in hepatocytes pre-treated with G15. Collectively, our data demonstrated that genistein improves glucose metabolism via activating the GPER-mediated cAMP/PKA-AMPK signaling pathway. These findings provide theoretical basis for genistein as a promising nutritional supplemental to alleviate metabolism disorders and related diseases in animals or even humans.


Assuntos
Proteínas Quinases Ativadas por AMP , Genisteína , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Galinhas/metabolismo , Receptor beta de Estrogênio , Estrogênios/farmacologia , Genisteína/farmacologia , Glucose/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
20.
Plant Physiol ; 189(3): 1715-1727, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35325212

RESUMO

Salicylic acid (SA) acts as a signaling molecule to perceive and defend against pathogen infections. Accordingly, pathogens evolve versatile strategies to disrupt the SA-mediated signal transduction, and how plant viruses manipulate the SA-dependent defense responses requires further characterization. Here, we show that barley stripe mosaic virus (BSMV) infection activates the SA-mediated defense signaling pathway and upregulates the expression of Nicotiana benthamiana thioredoxin h-type 1 (NbTRXh1). The γb protein interacts directly with NbTRXh1 in vivo and in vitro. The overexpression of NbTRXh1, but not a reductase-defective mutant, impedes BSMV infection, whereas low NbTRXh1 expression level results in increased viral accumulation. Similar with its orthologs in Arabidopsis (Arabidopsis thaliana), NbTRXh1 also plays an essential role in SA signaling transduction in N. benthamiana. To counteract NbTRXh1-mediated defenses, the BSMV γb protein targets NbTRXh1 to dampen its reductase activity, thereby impairing downstream SA defense gene expression to optimize viral cell-to-cell movement. We also found that NbTRXh1-mediated resistance defends against lychnis ringspot virus, beet black scorch virus, and beet necrotic yellow vein virus. Taken together, our results reveal a role for the multifunctional γb protein in counteracting plant defense responses and an expanded broad-spectrum antibiotic role of the SA signaling pathway.


Assuntos
Vírus de Plantas , Ácido Salicílico , Oxirredutases/metabolismo , Doenças das Plantas , Vírus de Plantas/metabolismo , Ácido Salicílico/metabolismo , Tiorredoxina h/genética , Tiorredoxina h/metabolismo , Nicotiana/metabolismo
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