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1.
Can J Physiol Pharmacol ; 99(10): 1057-1068, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34492212

RESUMO

G (1-5)-NH2, G (1-7)-NH2, and G (1-9) are the active fragments of ghrelin. The aim of this study was to investigate the antinociceptive effects, their ability to cross the blood-brain barrier, and the receptor mechanism(s) of these fragments using the tail withdrawal test in male Kunming mice. The antinociceptive effects of these fragments (2, 6, 20, and 60 nmol/mouse) were tested at 5, 10, 20, 30, 40, 50, and 60 min after intravenous (i.v.) injection. These fragments induced dose- and time-related antinociceptive effects relative to saline. Using the near infrared fluorescence imaging experiments, our results showed that these fragments could cross the brain-blood barrier and enter the brain. The antinociceptive effects of these fragments were completely antagonized by naloxone (intracerebroventricular, i.c.v.); however, naloxone methiodide (intraperitoneal, i.p.), which is the peripheral restricted opioid receptor antagonist, did not antagonize these antinociceptive effects. Furthermore, the GHS-R1α antagonist [D-Lys3]-GHRP-6 (i.c.v.) completely antagonized these antinociceptive effects, too. These results suggested that these fragments induced antinociceptive effects through central opioid receptors and GHS-R1α. In conclusion, our studies indicated that these active fragments of ghrelin could cross the brain-blood barrier and enter the brain and induce antinociceptive effects through central opioid receptors and GHS-R1α after intravenous injection.


Assuntos
Dor Aguda/tratamento farmacológico , Analgésicos/farmacologia , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Grelina/administração & dosagem , Grelina/farmacocinética , Temperatura Alta/efeitos adversos , Dor Aguda/etiologia , Dor Aguda/metabolismo , Dor Aguda/patologia , Animais , Animais não Endogâmicos , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Grelina/farmacologia , Masculino , Camundongos , Antagonistas de Entorpecentes/farmacologia , Receptores de Grelina/antagonistas & inibidores , Receptores de Grelina/metabolismo , Receptores Opioides/química , Receptores Opioides/metabolismo
2.
J Appl Toxicol ; 40(11): 1480-1490, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33020912

RESUMO

As an organophosphorus ester, tri-ortho-cresyl phosphate (TOCP) has been widely used in agriculture and industry. It is reported that TOCP can induce organophosphate-induced delayed neuropathy (OPIDN) in sensitive animal and human species. However, the exact molecular mechanisms underlying TOCP-induced neurotoxicity are still unknown. In this study, we found that TOCP could induce autophagy by activating protein kinase C alpha (PKCα) signaling in neuroblastoma SK-N-SH cells. PKCα activators could positively regulate TOCP-induced autophagy by increasing the expression levels of neighbor BRCA1 gene protein 1 (NBR1), LC3 and P62 autophagic receptor protein. Furthermore, PKCα activation impaired the ubiquitin-proteasome system (UPS), resulting in inhibition of proteasome activity and accumulation of ubiquitinated proteins. UPS dysfunction could stimulate autophagy to serve as a compensatory pathway, which contributed to the accumulation of the abnormally hyperphosphorylated tau proteins and degradation of impaired proteins of the MAP 2 and NF-H families in neurodegenerative disorders.


Assuntos
Autofagia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteína Quinase C-alfa/metabolismo , Tritolil Fosfatos/toxicidade , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neurofilamentos/metabolismo , Neurônios/enzimologia , Neurônios/ultraestrutura , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais , Ubiquitinação , Proteínas tau/metabolismo
3.
Basic Res Cardiol ; 111(2): 13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26786260

RESUMO

SIRT6, a member of the NAD(+)-dependent class III deacetylase sirtuin family, has been revealed to play important roles in promoting cellular resistance against oxidative stress. The formation of reactive oxygen species (ROS) and oxidative stress are the crucial mechanisms underlying cellular damage and dysfunction in cardiac ischemia/reperfusion (I/R) injury, but the role of SIRT6 in I/R-induced ROS and oxidative stress is poorly understood. In this study, by using heterozygous SIRT6 knockout (SIRT6(+/-)) mice and cultured neonatal cardiomyocyte models, we investigated how SIRT6 mediates oxidative stress and myocardial injury during I/R. Partial knockout (KO) of SIRT6 aggravated myocardial damage, ventricular remodeling, and oxidative stress in mice subjected to myocardial I/R, whereas restoration of SIRT6 expression by direct cardiac injection of adenoviral constructs encoding SIRT6 reversed these deleterious effects of SIRT6 KO in the ischemic heart. In addition, partial deletion of the SIRT6 gene decreased myocardial functional recovery following I/R in a Langendorff perfusion model. Similarly, the protective effects of SIRT6 were also observed in cultured cardiomyocytes following hypoxia/reoxygenation. Intriguingly, SIRT6 was noticed to up-regulate AMP/ATP and then activate the adenosine 5'-monophosphate-activated protein kinase (AMPK)-forkhead box O3α (FoxO3α) axis and further initiated the downstream antioxidant-encoding gene expression (manganese superoxide dismutase and catalase), thereby decreasing cellular levels of oxidative stress and mediating cardioprotection in the ischemic heart. These results suggest that SIRT6 protects the heart from I/R injury through FoxO3α activation in the ischemic heart in an AMP/ATP-induced AMPK-dependent way, thus upregulating antioxidants and suppressing oxidative stress.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Sirtuínas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Animais Recém-Nascidos , Antioxidantes/metabolismo , Apoptose , Catalase/metabolismo , Células Cultivadas , Regulação para Baixo , Proteína Forkhead Box O3 , Técnicas In Vitro , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Sirtuínas/genética , Superóxido Dismutase/metabolismo , Remodelação Ventricular
4.
Reproduction ; 149(2): 163-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25385720

RESUMO

Tri-ortho-cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners, and flame retardants in industry and reported to have a deleterious effect on the male reproductive system in animals besides delayed neurotoxicity. Our preliminary results found that TOCP could disrupt the seminiferous epithelium in the testis and inhibit spermatogenesis, but the precise mechanism is yet to be elucidated. This study shows that TOCP inhibited viability of rat spermatogonial stem cells in a dose-dependent manner. TOCP could not lead to cell cycle arrest in the cells; the mRNA levels of p21, p27, p53, and cyclin D1 in the cells were also not affected by TOCP. Meanwhile, TOCP did not induce apoptosis of rat spermatogonial stem cells. After treatment with TOCP, however, both LC3-II and the ratio of LC3-II/LC3-I were markedly increased; autophagy proteins ATG5 and beclin 1 were also increased after treatment with TOCP, indicating that TOCP could induce autophagy in the cells. Ultrastructural observation under the transmission electron microscopy indicated that autophagic vesicles in the cytoplasm containing extensively degraded organelles such as mitochondria and endoplasmic reticulum increased significantly after the cells were treated with TOCP. In summary, we have shown that TOCP can inhibit viability of rat spermatogonial stem cells and induce autophagy of the cells, without affecting cell cycle and apoptosis.


Assuntos
Autofagia/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Tritolil Fosfatos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/análise , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Microscopia Eletrônica de Transmissão , Proteínas/análise , Ratos , Espermatogônias/química , Espermatogônias/ultraestrutura , Células-Tronco/química , Células-Tronco/ultraestrutura
5.
Environ Toxicol ; 29(10): 1193-200, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23418109

RESUMO

Anticholinesterase pesticides have been widely used in agricultural and domestic settings and can be detected in the environment after long-term use. Although the acute toxic effects of chlorpyrifos and carbaryl have been well described, little is known about the chronic toxicity of the pesticides mixture. To investigate their chronic neurotoxicity, Wistar rats were exposed to chlorpyrifos, carbaryl, and their mixture (MIX) for 90 consecutive days. The activities of serum cholinesterase (ChE) as well as acetylcholinesterase (AChE) and neuropathy target esterase (NTE) in nerve tissues were determined. Furthermore, the histopathological examination was carried out. The results showed that ChE activity significantly decreased in all treated rats except the rats treated with low dose carbaryl. Treatment with middle- and high-dose chlorpyrifos and MIX in rats significantly inhibited AChE activity in the central nervous tissues, whereas treatment with carbaryl alone did not. In sciatic nerve, AChE activity was significantly inhibited by high-dose carbaryl and MIX, but not by chlorpyrifos alone. No significant NTE inhibition was observed in all treatment groups. Histopathological examination revealed that both chlorpyrifos and MIX treatment induced hippocampal damage. However, no obvious hippocampal damage was found in carbaryl-treated rats. Carbaryl and MIX, but not chlorpyrifos alone, induced pathological damage of sciatic nerve. Taken together, all of the results indicated that chlorpyrifos and carbaryl have different toxicological target tissues in nervous system and showed corresponding effects in the nervous tissues, which may reflect the different sensitivity of central and peripheral nervous tissues to different pesticides individually and in combination.


Assuntos
Carbaril/toxicidade , Clorpirifos/toxicidade , Inibidores da Colinesterase/toxicidade , Hipocampo/efeitos dos fármacos , Praguicidas/toxicidade , Nervo Isquiático/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Ratos , Ratos Wistar , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia
6.
J Cardiovasc Pharmacol ; 62(6): 512-23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24072175

RESUMO

Doxorubicin (DOX) is a potent available antitumor drug; however, its clinical use is limited by the cardiotoxicity. Salidroside (SLD), with strong antioxidative and cytoprotective actions, is of particular interest in the development of antioxidative therapies for oxidative injury in cardiac diseases. Now, the protection and underlying mechanisms of SLD against DOX-induced cardiotoxicity are still unknown. In the present study, we revealed both antioxidative mechanism and Bcl2-dependent survival signaling involved in SLD's protection. We observed that DOX exposure induced mortality elevation, body weight loss, and cardiac dysfunction in mice, increased lactate dehydrogenase leakage and cardiomyocyte apoptosis, but decreased cell viability and size in cardiac tissues and cultured H9c2 cells, respectively, which were effectively antagonized by SLD supplement. We further observed that SLD significantly reduced the intercellular oxidative stress level, partly by inhibiting NOX1 expression and augmenting the expression and activities of the endogenous antioxidative enzymes, catalase, and manganese superoxide dismutase. In addition, SLD treatment upregulated the antiapoptotic Bcl2 and downregulated the proapoptotic Bax and inhibited a downstream pathway of Bcl2/Bax and caspase-3 activity. Our results indicated that SLD effectively protected the cardiomyocytes against DOX-induced cardiotoxicity by suppressing the excessive oxidative stress and activating a Bcl2-mediated survival signaling pathway.


Assuntos
Antibióticos Antineoplásicos/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Cardiotônicos/uso terapêutico , Doxorrubicina/antagonistas & inibidores , Glucosídeos/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Fenóis/uso terapêutico , Disfunção Ventricular/prevenção & controle , Animais , Antibióticos Antineoplásicos/efeitos adversos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Cardiotônicos/farmacologia , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Doxorrubicina/efeitos adversos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Oxirredutases/antagonistas & inibidores , Oxirredutases/química , Oxirredutases/genética , Oxirredutases/metabolismo , Fenóis/farmacologia , Distribuição Aleatória , Ratos , Disfunção Ventricular/induzido quimicamente , Disfunção Ventricular/metabolismo , Disfunção Ventricular/fisiopatologia
7.
Heliyon ; 9(4): e15091, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37095973

RESUMO

Background: At present, the treatment of intracerebral hemorrhage (ICH)-induced secondary brain injury (ISB) is limited, and the curative effect is not good. Long noncoding RNAs (lncRNAs) have been reported to play a role in ISB after ICH. We preliminarily monitored the induction effect of lncRNA-pseudopodium-enriched atypical kinase 1 (PEAK1) on neuronal cell apoptosis after ICH through our previous study and further experimental verification. However, the specific role and mechanism of lncRNA-PEAK1 in neuronal cell apoptosis after ICH have not been reported. Methods: ICH cell models were established with hemin. Pro-inflammatory cytokines, cell proliferation, and apoptosis were evaluated by enzyme-linked immunosorbent assay, Cell Counting Kit-8 assay, flow cytometry, and terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. Moreover, lncRNA expression associated with apoptosis was confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The biological functions of lncRNA-PEAK1, miR-466i-5p, and caspase8 were conducted in vitro. Further, we used bioinformatics, a dual-luciferase reporter assay, and rescue experiments to understand the mechanisms of competitive endogenous RNAs. Results: qRT-PCR revealed that lncRNA-PEAK1 was markedly upregulated in ICH cell models. LncRNA-PEAK1 knockdown decreased the interleukin-1ß and tumor necrosis factor-alpha levels, promoted cell proliferation, weakened cell apoptosis, and downregulated the key molecular protein levels involved in the cell apoptosis pathway. Bioinformatics analysis and dual-luciferase reporter assay revealed that lncRNA bound to miR-466i-5p, and caspase 8 was a target of miR-466i-5p. The mechanistic analysis demonstrated that lncRNA-PEAK1/miR-466i-5p promoted neuronal cell apoptosis by activating the apoptosis pathway through caspase8 after ICH. Conclusion: Collectively, our investigation identified that the lncRNA-PEAK1/miR-446i-5p/caspase8 axis is closely related to neuronal cell apoptosis after ICH. Additionally, lncRNA-PEAK1 may be a potential target for ICH intervention.

8.
World J Clin Cases ; 11(11): 2482-2488, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37123316

RESUMO

BACKGROUND: Reports on perioperative anesthesia management in pediatric patients with difficult airways are scarce. In addition to relatively more difficulties in the technique of endotracheal intubation, the time for manipulation is restricted compared to adults. Securing the airways safely and avoiding the occurrence of hypoxemia in these patients are of significance. CASE SUMMARY: A 9-year-old boy with spastic cerebral palsy, severe malnutrition, thoracic scoliosis, thoracic and airway malformation, laryngomalacia, pneumonia, and epilepsy faced the risk of anesthesia during palliative surgery. After a thorough preoperative evaluation, a detailed scheme for anesthesia and a series of intubation tools were prepared by a team of anesthesiologists. Awake fiberoptic intubation is the widely accepted strategy for patients with anticipated difficult airways. Given the age and medical condition of the patient, we kept him sedated with spontaneous breathing during endotracheal intubation. The endotracheal intubation was completed on the second attempt after the failure of the first effort. Fortunately, the surgery was successful without postoperative complications. CONCLUSION: Dealing with difficult airways in the pediatric population, proper sedation allows time to intubate without interrupting spontaneous breathing. The appropriate endotracheal intubation method based on the patient's unique characteristics is the key factor in successful management of these rare cases.

9.
World J Clin Cases ; 10(15): 4957-4963, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35801021

RESUMO

BACKGROUND: Osteosarcoma is one of the most common primary malignant bone tumors and is more common in adolescents. The femur is the most common site of osteosarcoma, and many patients require total femur replacement. We reviewed the relevant literature and case findings, summarized and analyzed this case in combination with relevant literature, and in doing so improved the understanding of the technology. CASE SUMMARY: The case we report was a 15-year-old patient who was admitted to the hospital 15 days after the discovery of a right thigh mass. The diagnosis was osteosarcoma of the right femoral shaft. After completion of neoadjuvant chemotherapy and preoperative preparation, total right femoral resection + artificial total femoral replacement was performed. Then, chemotherapy was continued after surgery. The patient recovered well after treatment, and the function of the affected limb was good. No recurrence, metastasis, prosthesis loosening, dislocation, fracture or other complications were found during 18 years of follow-up. At present, the patient can still work and lives normally. The results of the medium- and long-term follow-up were satisfactory. CONCLUSION: Artificial total femur replacement is a feasible limb salvage operation for patients with femoral malignant tumors, and the results of medium- and long-term follow-up are satisfactory.

10.
Mol Cell Biochem ; 358(1-2): 67-73, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21678081

RESUMO

Epidermal growth factor (EGF) plays a role in male germ cell development, but the precise function is yet to be defined. This study shows that EGF stimulates rat spermatogonial proliferation in a dose-dependent manner and significantly increased the protein levels of phosphated c-Src (p-c-Src) and phosphated signal transducer and activator of transcription 3 (p-STAT3). Moreover, overexpression of c-Src tagged with enhanced green fluorescence protein (EGFP) in rat spermatogonial stem cells enhances the cell viability. In contrast, knockdown or inhibition of c-Src inhibits rat spermatogonial stem cell proliferation; EGF could not abrogate the inhibitory effect. Evidently, the content of p-STAT3 protein was increased in c-Src-expressing cells and decreased in c-Src-suppressing cells. Furthermore, knockdown or inhibition of STAT3 also suppressed cell viability; neither EGF nor increased c-Src could reverse the inhibitory effect. These results are the first evidence that EGF induces proliferation of rat spermatogonial stem cells through c-Src/STAT3 signal.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Espermatogônias/citologia , Células-Tronco/citologia , Células-Tronco/enzimologia , Animais , Proteína Tirosina Quinase CSK , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Quinases da Família src
11.
Sheng Li Xue Bao ; 63(3): 198-204, 2011 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-21681336

RESUMO

The present study was to determine the effect of c-SRC on the viability of human cervical cancer HeLa cells and the expression of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) of the cell. Post-transfection of c-SRC RNA interference vector, RT-PCR and Western blot were utilized to observe the contents of c-SRC mRNA and protein, respectively, in HeLa cells. The MTT was used to observe the viability of the cells. Cell cycle was observed by flow cytometry. The content of p-STAT3 in the cells was also investigated after knockdown of c-SRC. Knockdown of c-SRC significantly decreased the contents of c-SRC mRNA and protein in the cells. The viability of the cells decreased by 23.1%, 29.3%, 38.6% and 45.0% (all P < 0.05), respectively, after the cells were transfected with c-SRC RNA interference vector for 24, 48, 72, and 96 h. The number of S-phase cells decreased by 5.6%, 10.0%, 15.2% and 19.9% (all P < 0.05), respectively, after transfection of c-SRC RNA interference vector for 24, 48, 72, and 96 h. The content of p-STAT3 also decreased when c-SRC was knockdowned. Compared with the control group, after treatment of HeLa cells with STAT3 inhibitor Piceatannol for 24, 48, 72, and 96 h, the cell viability decreased by 23.8%, 29.7%, 37.3% and 45.4% (all P < 0.05), respectively, while increase of c-SRC content could not reverse the inhibitory effect. These results suggest that the inhibited viability of HeLa cells caused by knockdown of c-SRC is associated with the decreased content of p-STAT3 protein.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genes src/genética , Fator de Transcrição STAT3/metabolismo , Sobrevivência Celular , Feminino , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Fosforilação , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fator de Transcrição STAT3/genética , Transfecção
12.
Food Nutr Res ; 652021.
Artigo em Inglês | MEDLINE | ID: mdl-33613155

RESUMO

BACKGROUND: Saturated fatty acids (SFAs) generally have been thought to worsen insulin-resistance and increase the risk of developing type 2 diabetes mellitus (T2DM). Recently, accumulating evidence has revealed that SFAs are not a single homogeneous group, instead different SFAs are associated with T2DM in opposing directions. Pentadecanoic acid (C15:0, PA) is directly correlated with dairy products, and a negative association between circulating PA and metabolic disease risk was observed in epidemiological studies. Therefore, the role of PA in human health needs to be reinforced. Whether PA has a direct benefit on glucose metabolism and insulin sensitivity needs further investigation. OBJECTIVE: The present study aimed to investigate the effect and potential mechanism of action of PA on basal and insulin stimulated glucose uptake in C2C12 myotubes. METHODS: Glucose uptake was determined using a 2-(N-[7-nitrobenz-2-oxa-1,3-diazol-4-yl] amino)-2-deoxyglucose (2-NBDG) uptake assay. Cell membrane proteins were isolated and glucose transporter 4 (GLUT4) protein was detected by western blotting to examine the translocation of GLUT4 to the plasma membrane. The phosphorylation levels of proteins involved in the insulin and 5'-adenosine monophosphate-activated protein kinase (AMPK) pathways were examined by western blotting. RESULTS: We found that PA significantly promoted glucose uptake and GLUT4 translocation to the plasma membrane. PA had no effect on the insulin-dependent pathway involving insulin receptor substrate 1 (Tyr632) and protein kinase B (PKB/Akt), but increased phosphorylation of AMPK and Akt substrate of 160 kDa (AS160). Compound C (an AMPK inhibitor) blocked PA-induced AMPK activation and reversed PA-induced GLUT4 translocation, indicating that PA promotes glucose uptake via the AMPK pathway in vitro. Moreover, PA significantly promoted insulin-stimulated glucose uptake in myotubes. Under insulin stimulation, PA did not affect the insulin-dependent pathway, but still activated AMPK. CONCLUSION: PA, an odd-chain SFA, significantly stimulates glucose uptake via the AMPK-AS160 pathway and exhibits an insulin-sensitizing effect in myotubes.

13.
BMC Complement Med Ther ; 21(1): 128, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888116

RESUMO

BACKGROUND: Alisol A 24-acetate (AA-24-a), one of the main active triterpenes isolated from the well-known medicinal plant Alisma orientale (Sam.) Juz., exhibits multiple biological activities including hypolipidemic activity. However, its effect on lipid metabolism in adipocytes remains unclear. The present study aimed to clarify the effect of AA-24-a on adipocyte lipolysis and to determine its potential mechanism of action using 3 T3-L1 cells. METHODS: We assayed the release of glycerol into culture medium of 3 T3-L1 cells under treatment with AA-24-a. Protein and mRNA expression and phosphorylation levels of the main lipases and kinases involved in lipolysis regulation were determined by quantitative polymerase chain reaction and western blotting. Specific inhibitors of protein kinase A (PKA; H89) and extracellular signal-regulated kinase (ERK; PD98059), which are key enzymes in relevant signaling pathways, were used to examine their roles in AA-24-a-stimulated lipolysis. RESULTS: AA-24-a significantly stimulated neutral lipolysis in fully differentiated adipocytes. To determine the underlying mechanism, we assessed the changes in mRNA and protein levels of key lipolysis-related genes in the presence or absence of H89 and PD98059. Both inhibitors reduced AA-24-a-induced lipolysis. Moreover, pretreatment with H89 attenuated AA-24-a-induced phosphorylation of hormone-sensitive lipase at Ser660, while pretreatment with PD98059 attenuated AA-24-a-induced downregulation of peroxisome proliferator-activated receptor-γ and perilipin A. CONCLUSIONS: Our results indicate that AA-24-a promoted neutral lipolysis in 3 T3-L1 adipocytes by activating PKA-mediated phosphorylation of hormone-sensitive lipase and ERK- mediated downregulation of expression of perilipin A.


Assuntos
Alisma , Hipolipemiantes/farmacologia , Triterpenos/farmacologia , Adipócitos/efeitos dos fármacos , Animais , Lipólise/efeitos dos fármacos , Camundongos , Fitoterapia
14.
Pharmacol Res ; 62(3): 259-64, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20380879

RESUMO

As a phospholipase B, neuropathy target esterase (NTE) is responsible for the conversion of phosphatidylcholine (PC) to glycerophosphocholine (GPC). We examined the role of cAMP in the regulation of NTE in mammalian cells. Endogenous NTE activity was increased by cAMP-elevating chemicals, including dibutyryl cAMP, forskolin and forskolin plus 1-isobutyl-3-methylxanthine (IBMX), but decreased by the adenyl cyclase inhibitor SQ22536 which can reduce intracellular cAMP levels. Exogenous GFP-tagged NTE activity was not affected by changes in intracellular cAMP. NTE protein levels were up-regulated by the cAMP-elevating reagents and down-regulated by the inhibitor. The effect of the adenyl cyclase activator forskolin on NTE protein and mRNA levels was blocked by pretreatment with the protein kinase A (PKA) activity inhibitor H89. In addition, we found that changes in GPC, but not PC, levels were correlated with cAMP induced changes in NTE activity. These results are the first evidence that cAMP/PKA signals regulate NTE expression and GPC content in mammalian cells.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Hidrolases de Éster Carboxílico/genética , Regulação da Expressão Gênica , Células HeLa , Humanos
15.
Brain Res Bull ; 162: 20-29, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32442560

RESUMO

Secondary brain injuries following intracerebral hemorrhage (ICH) are mediated by inflammatory pathway activation. The present study aimed to characterize long noncoding RNAs (lncRNAs) that are differentially expressed in cerebral tissues during ICH pathogenesis and to investigate their pathogenic functions. An ICH mouse model established by collagenase injection was used to obtain differentially expressed lncRNAs for deep sequencing. A cellular inflammation model was established by treating mouse microglia with lipopolysaccharide. Expression of lncRNA and miRNA was assessed by quantitative RT-PCR, and protein abundance was measured by western blot. Cytokine levels in mouse serum and cell culture supernatants were analyzed using enzyme-linked immunosorbent assay. Cerebral injury was evaluated by hematoxylin-eosin and Nissl staining, the ratio of brain dry weight/brain wet weight, and neurobehavior scoring. Ionized calcium-binding adaptor molecule 1 (IBA1) expression in the brain sections was assessed using immunohistochemistry. A total of 3681 lncRNAs were differentially expressed in the brain tissue of the ICH mice group compared with the Sham group. Of these, lncRNA metastasis suppressor-1 (Mtss1) expression was increased. Mtss1 knockdown by siRNA in the cellular model strongly suppressed TIR-domain-containing adapter-inducing interferon-ß (TRIF) expression, P65 phosphorylation, and tumor necrosis factor (TNF)-α and interleukin (IL)-1ß secretion. Mtss1 knockdown in ICH mice inhibited secondary brain injury and decreased IBA1, TNF-α, and IL-1ß. Mtss1 was predicted to bind miR-709, and Mtss1 knockdown elevated miR-709 expression in the cellular inflammation model and ICH mice. High expression of Mtss1 promoted inflammatory brain injuries after ICH by enhancing inflammatory cytokine secretion and targeting miR-709 expression.


Assuntos
Lesões Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Mediadores da Inflamação/metabolismo , MicroRNAs/biossíntese , Proteínas dos Microfilamentos/biossíntese , Proteínas de Neoplasias/biossíntese , Animais , Lesões Encefálicas/genética , Lesões Encefálicas/patologia , Linhagem Celular , Hemorragia Cerebral/genética , Hemorragia Cerebral/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/genética , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética
16.
BMC Complement Med Ther ; 20(1): 22, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32020870

RESUMO

BACKGROUND: Alisol A-24-acetate (AA-24-a) is one of the main active triterpenes isolated from the well-known medicinal plant Alisma orientale (Sam.) Juz., which possesses multiple biological activities, including a hypoglycemic effect. Whether AA-24-a is a hypoglycemic-active compound of A. orientale (Sam.) Juz. is unclear. The present study aimed to clarify the effect and potential mechanism of action of AA-24-a on glucose uptake in C2C12 myotubes. METHOD: Effects of AA-24-a on glucose uptake and GLUT4 translocation to the plasma membrane were evaluated. Glucose uptake was determined using a 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxyglucose (2-NBDG) uptake assay. Cell membrane proteins were isolated and glucose transporter 4 (GLUT4) protein was detected by western blotting to examine the translocation of GLUT4 to the plasma membrane. To determine the underlying mechanism, the phosphorylation levels of proteins involved in the insulin and 5'-adenosine monophosphate-activated protein kinase (AMPK) pathways were examined using western blotting. Furthermore, specific inhibitors of key enzymes in AMPK signaling pathway were used to examine the role of these kinases in the AA-24-a-induced glucose uptake and GLUT4 translocation. RESULTS: We found that AA-24-a significantly promoted glucose uptake and GLUT4 translocation in C2C12 myotubes. AA-24-a increased the phosphorylation of AMPK, but had no effect on the insulin-dependent pathway involving insulin receptor substrate 1 (IRS1) and protein kinase B (PKB/AKT). In addition, the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and the AKT substrate of 160 kDa (AS160), two proteins that act downstream of AMPK, was upregulated. Compound C, an AMPK inhibitor, blocked AA-24-a-induced AMPK pathway activation and reversed AA-24-a-induced glucose uptake and GLUT4 translocation to the plasma membrane, indicating that AA-24-a promotes glucose metabolism via the AMPK pathway in vitro. STO-609, a calcium/calmodulin-dependent protein kinase kinase ß (CaMKKß) inhibitor, also attenuated AA-24-a-induced glucose uptake and GLUT4 translocation. Moreover, STO-609 weakened AA-24-a-induced phosphorylation of AMPK, p38 MAPK and AS160. CONCLUSIONS: These results indicate that AA-24-a isolated from A. orientale (Sam.) Juz. significantly enhances glucose uptake via the CaMKKß-AMPK-p38 MAPK/AS160 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Colestenonas/farmacologia , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Alisma/química , Animais , Western Blotting , Linhagem Celular , Camundongos , Fibras Musculares Esqueléticas/enzimologia , Projetos Piloto , Plantas Medicinais/química
17.
Chem Res Toxicol ; 22(6): 1026-33, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19522548

RESUMO

Chlorpyrifos (CPF) and carbaryl (CAR) have been widely used in agricultural and domestic settings. Previous studies have demonstrated that CPF and CAR are generally neurotoxic to mammals, whereas the toxicities of these pesticides to other organs and their potential interactive effects remain unclear. The purpose of this study assessed the alterations of histopathology, biochemical parameters, and metabolic profiles of serum in rats following the treatment with CPF and CAR alone or in combination. No histopathological changes were observed in the liver and kidney tissues. Biochemical analysis of blood showed that alanine aminotransferase and total bilirubin in serum increased slightly in CPF-treated rats as compared to controls. Metabonomic analysis revealed alternations in a number of metabolites involving the metabolism of glucose, free fatty acids, and amino acids in liver mitochondria. The treatment of rats with CPF alone resulted in a decrease in lactate, low- and very low-density lipoprotein (LDL/VLDL), dimethylglycine (DMG), and aspartate. This was accompanied by an increase in isoleucine and leucine, 3-hydroxybutyrate (3-HB), N-acetylglycoprotein (NAC), acetone, succinate, glutamine, choline, creatine, glucose, and amino acids in a dose-dependent manner. Similarly, treatment with a high dose of CAR alone led to a decrease in DMG, aspartate, LDL/VLDL, and dimethylamine and an increase in taurine, glucose, and amino acids. The levels of lactate and LDL/VLDL decreased, while those of 3-HB, NAC, acetone, succinate, and glutamine elevated in the group of rats treated with a mixture of CPF and CAR as compared to the groups of CPF or CAR alone. Our results suggest that subchronic exposure to CPF and CAR alone, or in combination, could cause a disturbance in energy and fatty acid metabolism in the liver mitochondria of rats. Overall, we have shown that analysis of metabolic profiles can make exceptional contributions to the understanding of the individual or mutual effects following exposure to a low dose of pesticides.


Assuntos
Carbaril/toxicidade , Clorpirifos/toxicidade , Inseticidas/toxicidade , Metaboloma/efeitos dos fármacos , Animais , Carbaril/sangue , Carbaril/metabolismo , Clorpirifos/sangue , Clorpirifos/metabolismo , Testes de Química Clínica , Feminino , Inseticidas/sangue , Inseticidas/metabolismo , Fígado/patologia , Pulmão/patologia , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Wistar
18.
Biochim Biophys Acta Mol Basis Dis ; 1865(9): 2379-2392, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31167124

RESUMO

BACKGROUND: Abnormalities of the L-arginine-nitric oxide pathway induce hypertension. 5-Lipoxygenase (5-LO) is the key enzyme involved in synthesis of leukotrienes (LTs). However, whether nitricoxide synthase dysfunction induces hypertensive vascular remodeling by regulating 5-LO activity and its downstream inflammatory metabolites remains unknown. METHODS AND RESULTS: Six-week L-NAME treatment significantly induced hypertension and vascular remodeling in both wild-type (WT) and 5-LO-knockout (5-LO-KO) mice, and blood pressure in caudal and carotid arteries was lower in 5-LO-KO than WT mice with L-NAME exposure. On histology, L-NAME induced less media thickness, media-to-lumen ratio, and collagen deposition and fewer Ki-67-positive vascular smooth muscle cells (VSMCs) but more elastin expression in thoracic and mesenteric aortas of 5-LO-KO than L-NAME-treated WT mice. L-NAME significantly increased LT content, including LTB4 and cysteinyl LT (CysLTs), in plasma and neutrophil culture supernatants from WT mice. On immunohistochemistry, L-NAME promoted the colocalization of 5-LO and 5-LO-activating protein on the nuclear envelope of cultured neutrophils, which was accompanied by elevated LT content in culture supernatants. In addition, LTs significantly promoted BrdU incorporation, migration and phenotypic modulation in VSMCs. CONCLUSION: L-NAME may activate the 5-LO/LT pathway in immune cells, such as neutrophils, and promote the products of 5-LO metabolites, including LTB4 and CysLTs, which aggravate vascular remodeling in hypertension. 5-LO deficiency may protect against hypertension and vascular remodeling by reducing levels of 5-LO downstream inflammatory metabolites.


Assuntos
Araquidonato 5-Lipoxigenase/genética , Hipertensão/prevenção & controle , Remodelação Vascular , Animais , Aorta/metabolismo , Aorta/patologia , Araquidonato 5-Lipoxigenase/deficiência , Pressão Sanguínea/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Hipertensão/induzido quimicamente , Hipertensão/patologia , Leucotrieno A4/sangue , Leucotrieno A4/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , NG-Nitroarginina Metil Éster/metabolismo , NG-Nitroarginina Metil Éster/toxicidade , Neutrófilos/imunologia , Neutrófilos/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Remodelação Vascular/efeitos dos fármacos
19.
Sheng Li Xue Bao ; 60(3): 391-6, 2008 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-18560731

RESUMO

The present study aimed to investigate the effect of proto-oncogene c-src on the viability of rat spermatogonial stem cells from 9 day-old rat in vitro. MTT method was used to observe the viability of the spermatogonial stem cells treated with antisense c-src oligodeoxynucleotides (ODNs) in vitro; RT-PCR was utilized to observe the expression of c-src mRNA and Western blot was used to observe the protein expressions of pp60c-src and phosphorylated signal transducer and activator of transcription-3 (p-STAT3). Compared with that in control group, the viability of spermatogonial stem cells decreased by 8.1% (P<0.05) and the expression of c-src mRNA decreased significantly after treatment with 10 µmol/L antisense c-src ODNs for 12 h. Compared with that in the control group, the protein expressions of pp60c-src and p-STAT3 decreased by 33.8% and 45.3% (both P<0.01), respectively, in the spermatogonial stem cells after being transfected with antisense c-src ODNs. The results suggest that proto-oncogene c-src regulates the viability of rat spermatogonial stem cells through p-STAT3.


Assuntos
Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Fator de Transcrição STAT3/metabolismo , Espermatogônias/citologia , Células-Tronco/citologia , Animais , Células Cultivadas , Genes src , Masculino , Fosforilação , RNA Mensageiro , Ratos , Espermatogônias/metabolismo , Células-Tronco/metabolismo , Transfecção
20.
Clin Neuroradiol ; 28(1): 17-24, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27154219

RESUMO

BACKGROUND: Posterior fossa brain arteriovenous malformations (PFbAVM) are relatively rare brain disorders but have a high risk of hemorrhage. Endovascular embolization to reduce the lesion size before treatment may improve the outcome of PFbAVM. The purposes of this study were to identify risk factors associated with hemorrhage in PFbAVM and to assess clinical outcomes in patients receiving initial endovascular embolization. MATERIAL AND METHODS: From 1999 to 2013 a total of 63 patients with PFbAVMs were treated (31 males and 32 females, 14.1 % of all AVM cases). A retrospective examination of patient demographics, clinical presentation, angiographic features, treatment modalities, complications and outcomes was carried out. The re-hemorrhage rate, obliteration rate and modified Rankin scale (MRS) were used as measures of outcome. RESULTS: Of the 63 PFbAVM patients 54 (85.7 %) exhibited hemorrhage and 15 had confirmed aneurysms. The cerebellar location (P = 0.007) and deep venous drainage (P = 0.012) were independent predictors of hemorrhage in multivariate analyses. The mean estimated devascularization was 46.9 % (range 10-100 %) in the 20 patients (31.7 %) treated by endovascular embolization. The 16 patients with residual niduses were further treated by radiosurgery, microsurgery or embolization. Complete obliteration was attained in 12 patients (67 %) while 2 (5.7 %) were left with persisting neurological deficits and 1 had a re-hemorrhage 3 years later (annual rate of 4.6 %). Favorable outcome (MRS ≤ 2) was obtained in the 20 patients receiving initial endovascular embolization (P = 0.039 versus preoperative MRS). CONCLUSION: Cerebellar location and deep venous drainage are predictors of hemorrhage in PFbAVM. Adjuvant endovascular embolization is useful and safe for PFbAVM prior to microsurgery or radiosurgery.


Assuntos
Malformações Arteriovenosas Intracranianas/terapia , Microcirurgia , Resultado do Tratamento , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Embolização Terapêutica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiocirurgia , Estudos Retrospectivos , Adulto Jovem
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