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1.
Hepatol Res ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153858

RESUMO

AIM: The study was conducted to evaluate the feasibility and safety profile of hepatic arterial infusion chemotherapy with oxaliplatin, 5-fluorouracil, and leucovorin (HAIC-FOLFOX) as an alternative therapeutic choice for patients with advanced hepatocellular carcinoma (HCC) that is refractory to systemic treatment including immune checkpoint blockades or molecular targeting agents. METHODS: Two hundred and forty five consecutive patients with advanced HCC who received HAIC-FOLFOX treatment after systemic treatment failure were retrospectively reviewed in six institutions and their survival, tumor response, and tolerance were assessed. RESULTS: The median overall survival (OS) and progression-free survival of the 209 included participants were 10.5 months (95% confidence interval [CI], 8.1-12.9) and 6.0 months (95% CI, 5.1-6.9), respectively. According to Response Evaluation Criteria in Solid Tumors 1.1 criteria, the objective response rate was 21.1%, and the disease control rate was 64.6%. Multivariate analysis of risk factors of OS were albumin-bilirubin grade (2 and 3 vs. 1, hazard ratio [HR] 1.57; 95% CI, 1.05-2.34; p = 0.028), tumor number (>3 vs. 1-3, HR 2.18; 95% CI, 1.10-4.34; p = 0.026), extrahepatic spread (present vs. absent, HR 1.61, 95% CI, 1.06-2.45; p = 0.027), synchronous systemic treatment (present vs. absent, HR 0.55, 95% CI, 0.37-0.83; p = 0.004) and treatment response (responder vs. nonresponder, HR 0.30, 95% CI, 0.17-0.53; p < 0.001). Grade 3-4 adverse events (AEs) occurred in 59 (28.2%) HCC patients. All AEs were manageable, and deaths related to hepatic artery infusion chemotherapy treatment were not observed. CONCLUSIONS: Our findings support the effectiveness and safety of HAIC-FOLFOX treatment for patients with advanced HCC who have failed systemic treatment.

2.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902384

RESUMO

Bone loss occurs in astronauts during long-term space flight, but the mechanisms are still unclear. We previously showed that advanced glycation end products (AGEs) were involved in microgravity-induced osteoporosis. Here, we investigated the improvement effects of blocking AGEs formation on microgravity-induced bone loss by using the AGEs formation inhibitor, irbesartan. To achieve this objective, we used a tail-suspended (TS) rat model to simulate microgravity and treated the TS rats with 50 mg/kg/day irbesartan, as well as the fluorochrome biomarkers injected into rats to label dynamic bone formation. To assess the accumulation of AGEs, pentosidine (PEN), non-enzymatic cross-links (NE-xLR), and fluorescent AGEs (fAGEs) were identified in the bone; 8-hydroxydeoxyguanosine (8-OHdG) was analyzed for the reactive oxygen species (ROS) level in the bone. Meanwhile, bone mechanical properties, bone microstructure, and dynamic bone histomorphometry were tested for bone quality assessment, and Osterix and TRAP were immunofluorescences stained for the activities of osteoblastic and osteoclastic cells. Results showed AGEs increased significantly and 8-OHdG expression in bone showed an upward trend in TS rat hindlimbs. The bone quality (bone microstructure and mechanical properties) and bone formation process (dynamic bone formation and osteoblastic cells activities) were inhibited after tail-suspension, and showed a correlation with AGEs, suggesting the elevated AGEs contributed to the disused bone loss. After being treated with irbesartan, the increased AGEs and 8-OHdG expression were significantly inhibited, suggesting irbesartan may reduce ROS to inhibit dicarbonyl compounds, thus suppressing AGEs production after tail-suspension. The inhibition of AGEs can partially alter the bone remodeling process and improve bone quality. Both AGEs accumulation and bone alterations almost occurred in trabecular bone but not in cortical bone, suggesting AGEs effects on bone remodeling under microgravity are dependent on the biological milieu.


Assuntos
Produtos Finais de Glicação Avançada , Osteoporose , Ratos , Animais , Irbesartana , Produtos Finais de Glicação Avançada/metabolismo , Espécies Reativas de Oxigênio , Osso e Ossos/metabolismo
3.
Signal Transduct Target Ther ; 8(1): 74, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36810450

RESUMO

Dysfunctions of ATP-binding cassette, subfamily D, member 1 (ABCD1) cause X-linked adrenoleukodystrophy, a rare neurodegenerative disease that affects all human tissues. Residing in the peroxisome membrane, ABCD1 plays a role in the translocation of very long-chain fatty acids for their ß-oxidation. Here, the six cryo-electron microscopy structures of ABCD1 in four distinct conformational states were presented. In the transporter dimer, two transmembrane domains form the substrate translocation pathway, and two nucleotide-binding domains form the ATP-binding site that binds and hydrolyzes ATP. The ABCD1 structures provide a starting point for elucidating the substrate recognition and translocation mechanism of ABCD1. Each of the four inward-facing structures of ABCD1 has a vestibule that opens to the cytosol with variable sizes. Hexacosanoic acid (C26:0)-CoA substrate binds to the transmembrane domains (TMDs) and stimulates the ATPase activity of the nucleotide-binding domains (NBDs). W339 from the transmembrane helix 5 (TM5) is essential for binding substrate and stimulating ATP hydrolysis by substrate. ABCD1 has a unique C-terminal coiled-coil domain that negatively modulates the ATPase activity of the NBDs. Furthermore, the structure of ABCD1 in the outward-facing state indicates that ATP molecules pull the two NBDs together and open the TMDs to the peroxisomal lumen for substrate release. The five structures provide a view of the substrate transport cycle and mechanistic implication for disease-causing mutations.


Assuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Doenças Neurodegenerativas , Humanos , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina , Microscopia Crioeletrônica , Nucleotídeos/metabolismo , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/química , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética
4.
Comput Methods Biomech Biomed Engin ; 26(3): 249-260, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35363098

RESUMO

Osteocytes play an important role in mechanosensation and conduction in bone tissue, and the change of mechanical environment can affect the sensitivity of osteocytes to external stimulation. The structure of osteocytes will be changed when they are subjected to vibrations, which influence the mechanosensitivity of osteocytes and alter the regulation of bone remodeling process. As an important mechanotransduction structure in osteocytes, the membrane skeleton greatly affects the mechanosensation and conduction of osteocytes. However, the dynamic responses of membrane skeleton to the vibration and the structural changes of membrane skeleton are unclear. Therefore, we applied a nonlinear dynamics method to explain the time-dependent changes of membrane skeleton. The semi-ellipsoidal reticulate shell structure of membrane skeleton is built based on the experimental observation in our previous work. Then, the nonlinear dynamic equations of membrane skeleton are established according to the theory of plate and shell dynamics, and the displacement-time curves, phase portraits, and Poincaré maps of membrane skeleton structure were obtained. The numeration results show that under the vibration stimulation of 15 Hz, 30 Hz, 60 Hz, and 90 Hz, the membrane skeleton is destroyed after a transient equilibrium position vibration. The vibration of 15 Hz has the most destructive effect on the membrane skeleton, the natural frequency of membrane skeleton may be less than 15 Hz. In addition, the chaos phenomenon occurs to the membrane skeleton during vibration. As a damping factor, the existence of viscosity alleviates the damage of structure. This study can help us to understand the oscillation characteristic of membrane skeleton in osteocyte.


Assuntos
Mecanotransdução Celular , Osteócitos , Mecanotransdução Celular/fisiologia , Osteócitos/fisiologia , Dinâmica não Linear , Osso e Ossos , Vibração
5.
Front Surg ; 9: 886237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747431

RESUMO

Objective: A nomogram was developed in this work to predict the probability of delayed cerebral infarction (DCI) after ruptured intracranial aneurysms (RIA) clipping. Methods: Clinical data of patients with intracranial aneurysm were obtained from the neurosurgery department of the First Affiliated Hospital of Chongqing Medical University from January 2016 to December 2020. A total of 419 patients receiving surgery of ruptured intracranial aneurysm clipping were included and a total of 37 patients with DCI were set as the observation group. The control group consisted of 382 patients without DCI. Risk factors of DCI were screened by univariate and multivariate logistic regression analysis and included in the nomogram. Results: Univariate analysis showed that female (P = 0.009), small aneurysm (P = 0.031), intraoperative aneurysm rupture (P = 0.007) and cerebral vasospasm (P < 0.001) were risk factors for postoperative DCI while smoking history (P = 0.044) were protective factors for postoperative DCI. Multivariate Logistic regression analysis showed that small aneurysm (P = 0.002, OR = 3.332, 95%-7.104), intraoperative aneurysm rupture (P = 0.004, OR = 0.122, 95%-CI, 0.029-0.504)and cerebral vasospasm (P < 0.001, OR = 0.153, 95%-CI, 0.070-0.333) were independent risk factors of postoperative DCI. The calibration curve of the probability of occurrence showed that the nomogram was in good correspondence with the observed results with a C-index of 0.766 (95% CI, 0.684-0.848). Meanwhile, the Decision curve analysis (DCA) showed that the established predictive model had a good clinical net benefit. Conclusion: The well-established nomogram is expected to be an effective tool to predict the occurrence of DCI after intracranial ruptured aneurysm and can be used to assist clinicians to develop more effective treatment strategies and improve the prognosis of patients.

6.
FASEB J ; 36(2): e22114, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35076958

RESUMO

Decades of spaceflight studies have provided abundant evidence that individual cells in vitro are capable of sensing space microgravity and responding with cellular changes both structurally and functionally. However, how microgravity is perceived, transmitted, and converted to biochemical signals by single cells remains unrevealed. Here in this review, over 40 cellular biology studies of real space fights were summarized. Studies on cells of the musculoskeletal system, cardiovascular system, and immune system were covered. Among all the reported cellular changes in response to space microgravity, cytoskeleton (CSK) reorganization emerges as a key indicator. Based on the evidence of CSK reorganization from space flight research, a possible mechanism from the standpoint of "cellular mechanical equilibrium" is proposed for the explanation of cellular response to space microgravity. Cytoskeletal equilibrium is broken by the gravitational change from ground to space and is followed by cellular morphological changes, cell mechanical properties changes, extracellular matrix reorganization, as well as signaling pathway activation/inactivation, all of which ultimately lead to the cell functional changes in space microgravity.


Assuntos
Citoesqueleto/fisiologia , Humanos , Sistema Imunitário/fisiologia , Transdução de Sinais/fisiologia , Voo Espacial/métodos , Ausência de Peso
7.
Biochem Biophys Res Commun ; 568: 151-157, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217013

RESUMO

Osteocytes are extremely sensitive to mechanical loading and govern bone remodeling process. Advanced glycation end products (AGEs) have the capacity to induce osteocyte apoptosis. In order to investigate the effects of AGEs on the mechanosensitivity of osteocytes, the osteocytic-like cells (MLO-Y4) were treated with low (50 µg/ml) and high (400 µg/ml) concentrations of AGEs for 1day and exposed to 15 dyne/cm2 of fluid shear stress. Then the F-actin cytoskeleton, prostaglandin E2(PGE2), Nitric oxide (NO), the Wnt/ß-catenin signaling pathway activity mRNA expressions were detected for osteocytes mechanical response changes; osteocalcin (OCN) and receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin (OPG) were detected for the regulation on bone remodeling function of osteocytes. The results showed that AGEs accumulation inhibited the sense of osteocytes to external mechincal loading, promoted shear-induced NO and PGE2 release, suppressed the mechanosensitivity of Wnt/ß-catenin signaling pathway, and furthermore promoted OCN and RANKL/OPG mRNA expressions. These indicated AGEs had an adverse impact on the mechanosensitivity of osteocytes, and led to a negative effect on their regulation of bone remodeling process under mechanical stimulation. This work provides a new perspective to interpret the alteration mechanism of osteocytes mechanosensitivity and provides a novel clue for exploring the mechanism of osteoporosis.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Osteócitos/metabolismo , Animais , Fenômenos Biomecânicos , Linhagem Celular , Camundongos , Osteócitos/citologia , Estresse Mecânico
8.
Calcif Tissue Int ; 107(6): 625-635, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32940720

RESUMO

Primary cilia are responsible for sensing mechanical loading in osteocytes. However, the underlying working mechanism of cilia remains elusive. An osteocyte model is necessary to reveal the role of cilia. Furthermore, the osteocyte model should be with upregulated or downregulated primary cilium expression. Herein, we used a pharmacological method to regulate the cilium formation of osteocytes. After screening, some pharmacological agents can regulate the cilium formation of osteocytes. We performed a CCK-8 assay to analyze the optimal working conditions of the drugs for MLO-Y4 cells. The agents include chloral hydrate (CH), Gd3+, Li+, and rapamycin. The expression of cilia affects the cellular functions, including mechanosensitivity, of osteocytes. Results showed that CH downregulated the cilium formation and ciliogenesis of osteocytes. In addition, Gd3+, Li+, and rapamycin upregulated the cilium expression of osteocytes. Moreover, the cilium expression positively correlated with the mechanosensitivity of osteocytes. This work reveals the role of primary cilia in the mechanosensing of osteocytes.


Assuntos
Hidrato de Cloral/farmacologia , Cílios/efeitos dos fármacos , Mecanotransdução Celular , Osteócitos/citologia , Sirolimo/farmacologia , Animais , Linhagem Celular , Camundongos
9.
Biochem Biophys Res Commun ; 530(1): 167-172, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32828281

RESUMO

It is hard to explain the decrease in mechanosensitivity of osteocytes under microgravity. Primary cilia are essential mechanosensor for osteocytes. The cilia become shorter under the simulated microgravity (SMG) environment. The cilia change may be the reason for the mechanosensitivity decrease of osteocytes under SMG. To reveal the role of primary cilia in weightless-induced osteocyte dysfunction, we investigate intraflagellar transport (IFT) to understand the mechanism of the decreased cilia length of osteocytes when subjected to SMG. We measure the number of anterograde IFT particles with GFP::IFT88 and retrograde IFT particles with OFP::IFT43 that occur at a particular transverse plane of the cilia. We also measure the expression of IFT88 and IFT43 and the size of IFT particles under SMG. Herein, the ratio of anterograde/retrograde particle number and the ratio of protein expression of IFT88/IFT43 increase under SMG. The size of anterograde IFT particles with GFP::IFT88 gets a significant decrease under SMG. Fundamentally, SMG has broken the balanced operating state of IFT and makes the IFT particles smaller. The phenomenon under SMG is intriguing.


Assuntos
Cílios/metabolismo , Osteócitos/citologia , Simulação de Ausência de Peso , Animais , Transporte Biológico , Linhagem Celular , Cílios/ultraestrutura , Camundongos , Osteócitos/metabolismo , Osteócitos/ultraestrutura
10.
Inflammation ; 43(1): 109-122, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696351

RESUMO

Visfatin acts as a significant regulator of inflammatory cytokines. However, the immunological response and therapeutic effects of visfatin under bacterial stress in murine lung tissue are still not clear. To investigate the role of visfatin on lipopolysaccharide (LPS)-induced acute lung injury (ALI), thirty Kunming mice were divided into Saline, LPS, and LPS + visfatin groups. After routine blood examination, the effects of visfatin on inflammatory cytokines, lung tissue structure, and expression of inflammatory mediators were explored through hematoxylin-eosin (H&E), Masson and immunohistochemical staining, quantitative polymerase chain reaction (Q-PCR), and Western blotting. Compared with the Saline group, neutrophil percentage, peripheral blood neutrophil count, and the ratio of lymphocyte count (NLR) were upregulated in LPS group. Moreover, Masson staining showed alterations in lung tissue structure; the mRNA level of different cytokines (IL-6, IL-1ß, TNF-α, IL-10, TLR4, IFN-γ) was upregulated; and the protein expression of interleukin (IL)-6, myeloperoxidase (MPO), and transforming growth factor-ß1 (TGF-ß) was significantly (p < 0.05) different in LPS group. Compared with LPS group, neutrophil percentage significantly decreased (p < 0.01), the numbers of lymphocytes significantly (p < 0.05) increased, NLR decreased, Masson staining of the lung was extremely different (p < 0.01), the structure of the lung was slightly damaged, and the myeloperoxidase values of lung showed no differences in LPS + visfatin. Hence, visfatin inhibits the lung inflammation induced by ALI. During the ALI, visfatin acts by decreasing NLR, downregulated the expression of MPO, enhanced antioxidant capacity, and regulated the inflammatory factors IL-1ß, IL-6, IL-10, and TNF-α to reduce the lung injury.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Anti-Inflamatórios/farmacologia , Citocinas/farmacologia , Pulmão/efeitos dos fármacos , Nicotinamida Fosforribosiltransferase/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Peroxidase/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/prevenção & controle , Fator de Crescimento Transformador beta1/metabolismo
11.
Bone ; 128: 112056, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31376534

RESUMO

Vibration at high frequency has been demonstrated to be anabolic for bone and embedded osteocytes. The response of osteocytes to vibration is frequency-dependent, but the mechanism remains unclear. Our previous computational study using an osteocyte finite element model has predicted a resonance effect involving in the frequency-dependent response of osteocytes to vibration. However, the cellular spontaneous vibratory motion of osteocytes has not been confirmed. In the present study, the cellular vibratory motions (CVM) of osteocytes were recorded by a custom-built digital holographic microscopy and quantitatively analyzed. The roles of ATP and spectrin network in the CVM of osteocytes were studied. Results showed the MLO-Y4 osteocytes displayed dynamic vibratory motions with an amplitude of ~80 nm, which is relied both on the ATP content and spectrin network. Spectrum analysis showed several frequency peaks in CVM of MLO-Y4 osteocytes at 30 Hz, 39 Hz, 83 Hz and 89 Hz. These peak frequencies are close to the commonly used effective frequencies in animal training and in-vitro cell experiments, and show a correlation with the computational predictions of the osteocyte finite element model. These results implicate that osteocytes are dynamic and the cellular dynamic motion is involved in the cellular mechanotransduction of vibration.


Assuntos
Trifosfato de Adenosina/metabolismo , Osteócitos/citologia , Osteócitos/metabolismo , Espectrina/metabolismo , Animais , Linhagem Celular , Camundongos
12.
Arch Immunol Ther Exp (Warsz) ; 67(4): 249-261, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31143985

RESUMO

Visfatin is involved in the body's inflammation and immune response. Inflammation could promote, while visfatin may directly or indirectly mitigate the effects of apoptosis and autophagy. Whether visfatin lessens the detrimental effects of lipopolysaccharide (LPS)-induced mouse acute lung injury (ALI) is poorly understood yet. Therefore, in the current study, the regulation mechanism of visfatin on apoptosis and autophagy was explored in Kunming mice by replicating LPS-induced inflammatory ALI model. Based on the mouse model of ALI, HE staining, TUNEL, transmission electron microscopy, immunohistochemical staining, real-time fluorescence quantitative PCR and western blot were used and the results showed that the alveolar septum was thinner than that of the LPS group, slight lung interstitial and alveolar exudation appeared, and a small number of inflammatory cell infiltration was found in the visfatin intervention group, indicating reduced tissue damage in lungs. After visfatin treatment, the expression of pro-apoptotic genes Bax, Bik, and p53 decreased and the expression of anti-apoptotic genes Bcl-2 and Bcl-xl increased, and expression of autophagy factors LC3 and Beclin1 decreased, indicating that visfatin inhibits apoptosis and reduces autophagy. The expression of PI3K and p-AKT was upregulated in the visfatin intervention group, the expression of AKT was downregulated, and the PI3K/AKT signaling pathway was activated. Hence, visfatin could activate the PI3K/AKT signaling pathway, reduce the apoptotic rate in alveolar epithelial cells and the level of autophagy in ALI by regulating the expression of autophagy factors, ultimately causing a protective effect on lung tissue.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Citocinas/metabolismo , Pulmão/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Animais , Apoptose , Autofagia , Células Cultivadas , Modelos Animais de Doenças , Humanos , Lipopolissacarídeos/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
13.
Microb Pathog ; 117: 55-59, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29412160

RESUMO

Visfatin plays an important role in regulation of inflammatory cytokines. However, the role of visfatin under bacterial stress condition is not fully explored yet. Therefore, the present study was conducted for the better understanding of the regulation mechanism of visfatin on the production of inflammatory cytokines under lipopolysaccharide (LPS) stress in RAW264.7 murine macrophages. Enzyme Linked Immuno-sorbent Assay (ELISA) results showed that, as compared to the control group, visfatin significantly up-regulated the levels of interleukin (IL)-1ß, IL-6, IL-10, tumor necrosis factor (TNF)-α (P < 0.05). Compared to the LPS group, the levels of IL-1ß, IL-10, TNF-α was down-regulated in visfatin + LPS group (P < 0.05). After adding p38 inhibitor, SB203580 to culture, the production of IL-1ß, IL-6, IL-10, TNF-α was significantly reduced as compared to visfatin only (P < 0.01). The results showed that visfatin may regulate the production of IL-1ß, IL-6, IL-10, TNF-α through the p38 signaling pathway. As compared to the PBS group, phosphorylayed p38 (P-p38) level in visfatin group was significantly decreased (P < 0.05). Compared with LPS group, P-p38 level was significantly decreased in visfatin + LPS group (P < 0.05). Hence, it is concluded that visfatin can significantly increase the levels of IL-1ß, IL-10 and TNF-α in normal conditions, while their levels significantly decrease during inflammation. Moreover, visfatin participates in the inflammatory response through the p38 mitogen-activated protein kinase (MAPK) signal pathway by the up-regulation of p38 and down-regulation of P-p38 levels.


Assuntos
Citocinas/metabolismo , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Nicotinamida Fosforribosiltransferase/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Regulação para Baixo , Inflamação , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Camundongos , Fosforilação , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Sci Rep ; 7: 40940, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28112189

RESUMO

The spectrin is first identified as the main component of erythrocyte membrane skeleton. It is getting growing attention since being found in multiple nonerythroid cells, providing complex mechanical properties and signal interface under the cell membrane. Recent genomics studies have revealed that the spectrin is highly relevant to bone disorders. However, in osteocytes, the important mechanosensors in bone, the role of spectrin is poorly understood. In this research, the role of spectrin in the mechanotransduction of MLO-Y4 osteocytes was studied. Immunofluorescence staining showed that, the spectrins were elaborately organized as a porous network throughout the cytoplasm, and linked with F-actin into a dense layer underlying the cell membrane. AFM results indicate that, the spectrin is pivotal for maintaining the overall elasticity of osteocytes, especially for the cell cortex stiffiness. Disruption of the spectrin network caused obvious softening of osteocytes, and resulted in a significant increase of Ca2+ influx, NO secretion, cell-cell connections and also induced a translocation of eNOS from membrane to cytoplasm. These results indicate that the spectrin network is a global structural support for osteocytes involving in the mechanotransduction process, making it a potential therapeutic target for bone disorders.


Assuntos
Mecanotransdução Celular , Osteócitos/fisiologia , Espectrina/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular , Citoplasma/química , Elasticidade , Camundongos , Microscopia de Força Atômica , Microscopia de Fluorescência , Ligação Proteica
15.
Acta Histochem ; 119(1): 26-31, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27884396

RESUMO

This study was undertaken to determine if visfatin is involved in the inflammation or apoptosis introduced by LPS in rats. Forty 8-week old Wistar rats were divided into four groups (n=10 in each group) and injected with saline, visfatin, LPS and visfatin+LPS co-stimulated via caudal vein. The duodenum, jejunum and ileum were harvested from all the rats. Compared to the saline treated group, visfatin significantly increased the number of TUNEL-positive apoptotic cells and the expression of caspase-3 protein in intestinal mucosa. Similarly, ELISA and western blot analysis also showed the up-regulation of pro-caspase-3 and cleaved caspase-3 expression in the visfatin group compared to the control group. In contrast to LPS, visfatin down-regulated the expression of cleaved-caspase-3 in the visfatin+LPS co-stimulated group, resulting in a significant decrease in apoptosis in intestinal mucosal cells. We observed more pro-caspase-3 positive cells in the visfatin+LPS co-stimulated group. The results indicate that, in the presence of LPS, visfatin plays an important role in the regulation of cell apoptosis and inflammation.


Assuntos
Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Nicotinamida Fosforribosiltransferase/farmacologia , Animais , Caspase 3/genética , Caspase 3/metabolismo , Combinação de Medicamentos , Duodeno/citologia , Duodeno/efeitos dos fármacos , Duodeno/imunologia , Células Epiteliais/citologia , Células Epiteliais/imunologia , Expressão Gênica , Íleo/citologia , Íleo/efeitos dos fármacos , Íleo/imunologia , Marcação In Situ das Extremidades Cortadas , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Jejuno/citologia , Jejuno/efeitos dos fármacos , Jejuno/imunologia , Ratos , Ratos Wistar
16.
Int. j. morphol ; 34(3): 830-835, Sept. 2016. ilus
Artigo em Inglês | LILACS | ID: biblio-828948

RESUMO

Boron is an essential trace element which plays an important role in process of metabolism and the function of the tissues. However, the effects of boron on the intestinal cells in African ostrich chicks are poorly reported. Therefore, this study was designed to investigate the role of boron on proliferation and apoptosis of the intestinal cells. A total of 36, ten day-old ostrich chicks were randomly divided into six groups and fed on the same basal diet supplemented with 0, 40, 80, 160, 320 and 640 mg/L boric acid in drinking water for 80 days. Proliferatingcell nuclearantigen (PCNA) wasused to test the proliferation indexof intestine in different group byimmunohistochemicalstaining (IHC). Apoptoticcellsofintestinewere detectedbyDutp-biotin nick end labeling (TUNEL) reaction and evaluated by integral optical density (IOD). Results showed that proliferationof intestinal cells significantly increased in groups of 80, 160, 320 and 640 mg/L. TUNEL reaction showed that apoptosis significantly decreased in 80 mg/L groups, while significantly increased in high dose of boron groups (320 and 640 mg/L), especially inepithelium. In conclusion, low dose of boron-supplemented water could promote cell proliferation and depress apoptosis, while high dose of boron could cause intestinal apoptosis and thus we found increased proliferation of intestine cell as a compensatory adaption. These findings may support optimal dosage of boron that could protect the development of ostrich intestine, while high dosage of boron could suppress it, or even has toxic effects on it.


El boro es un elemento esencial que desempeña un importante rol en el proceso del metabolismo y en la función de los tejidos. Sin embargo, existe poca información de los efectos del boro en las células intestinales de polluelos de avestruz Africana. Por lo tanto, este estudio fue diseñado para investigar el papel del boro sobre la proliferación y la apoptosis de las células intestinales. Un total de 36 polluelos de avestruz de diez días se dividieron, aleatoriamente, en seis grupos y se alimentaron con una misma dieta basal suplementada con 0, 40, 80, 160, 320 y 640 mg/L de ácido bórico en agua potable durante 80 días. Se utilizó el antígeno nuclear celular de células en proliferación (PCNA) para probar el índice de proliferación de intestino en diferentes grupos por tinción inmunohistoquímica. Las células apoptóticas del intestino fueron detectadas por dUTP-biotina nick etiquetado para reacción (TUNEL) y evaluadas por la densidad óptica integrada (DOI). Los resultados mostraron que la proliferación de las células intestinales aumentó significativamente en los grupos de 80, 160, 320 y 640 mg /L. La reacción TUNEL mostró que la apoptosis se redujo significativamente en los grupos de 80 mg/L, mientras que el aumento fue significativo en grupos tratados con dosis alta de boro (320 y 640 mg/L), especialmente en el epitelio. En conclusión, la baja dosis de boro en agua suplementada podría promover la proliferación celular y deprimir la apoptosis, mientras que altas dosis de boro podrían provocar apoptosis intestinal y, por lo tanto, se halló una mayor proliferación de las células del intestino como una adaptación compensatoria. Estos hallazgos indican que una dosis óptima de boro podría proteger el desarrollo del intestino del avestruz, mientras que altas dosis de boro podrían suprimirla, o incluso tener efectos tóxicos sobre ella.


Assuntos
Animais , Boro/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Struthioniformes/anatomia & histologia , Apoptose/efeitos dos fármacos , Imuno-Histoquímica , Intestinos/citologia
17.
Cell Biol Int ; 40(4): 397-406, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26715381

RESUMO

Vibration, especially at low magnitude and high frequency (LMHF), was demonstrated to be anabolic for bone, but how the LMHF vibration signal is perceived by osteocytes is not fully studied. On the other hand, the mechanotransduction of osteocytes under shear stress has been scientists' primary focus for years. Due to the small strain caused by low-magnitude vibration, whether the previous explanation for shear stress will still work for LMHF vibration is unknown. In this study, a finite element method (FEM) model based on the real geometrical shape of an osteocyte was built to compare the mechanical behaviors of osteocytes under LMHF vibration and shear stress. The bio-response of osteocytes to vibration under different frequencies, including the secretion of soluble factors and the concentration of intracellular calcium, were studied. The regulating effect of the conditioned medium (CM) from vibrated osteocytes on osteoblasts was also studied. The FEM analysis result showed the cell membrane deformation under LMHF vibration was very small (with a peak value of 1.09%) as compared to the deformation caused by shear stress (with a peak value of 6.65%). The F-actin stress fibers of osteocytes were reorganized, especially on the nucleus periphery after LMHF vibration. The vibration at 30 Hz has a promoting effect on osteocytes and the osteogenesis of osteoblasts, whereas vibration at 90 Hz was suppressive. These results lead to a conclusion that the bio-response of osteocytes to LMHF vibration is frequency-dependent and is more related to the cytoskeleton on nuclear periphery rather than the membrane deformation.


Assuntos
Osteócitos/metabolismo , Vibração , Actinas/metabolismo , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citoesqueleto/efeitos dos fármacos , Dinoprostona/metabolismo , Humanos , Mecanotransdução Celular , Microscopia Confocal , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Osteócitos/citologia , Osteogênese/efeitos dos fármacos , Resistência ao Cisalhamento
18.
Life Sci Space Res (Amst) ; 6: 15-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26256623

RESUMO

Space flight has been shown to induce bone loss and muscle atrophy, which could initiate the degeneration of articular cartilage. Countermeasures to prevent bone loss and muscle atrophy have been explored, but few spaceflight or ground-based studies have focused on the effects on cartilage degeneration. In this study, we investigated the effects of exercise on articular cartilage deterioration in tail-suspended rats. Thirty-two female Sprague-Dawley rats were randomly divided into four groups (n=8 in each): tail suspension (TS), tail suspension plus passive motion (TSP), tail suspension plus active exercise (TSA), and control (CON) groups. In the TS, TSP, and TSA groups, the rat hindlimbs were unloaded for 21 days by tail suspension. Next, the cartilage thickness and volume, and the attenuation coefficient of the distal femur were evaluated by micro-computed tomography (µCT). Histological analysis was used to assess the surface integrity of the cartilage, cartilage thickness, and chondrocytes. The results showed that: (1) the cartilage thickness on the distal femur was significantly lower in the TS and TSP groups compared with the CON and TSA groups; (2) the cartilage volume in the TS group was significantly lower compared with the CON, TSA, and TSP groups; and (3) histomorphology showed that the chondrocytes formed clusters where the degree of matrix staining was lower in the TS and TSP groups. There were no significant differences between any of these parameters in the CON and TSA groups. The cartilage thickness measurements obtained by µCT and histomorphology correlated well. In general, tail suspension could induce articular cartilage degeneration, but active exercise was effective in preventing this degeneration in tail-suspended rats.


Assuntos
Cartilagem Articular/patologia , Fêmur/patologia , Elevação dos Membros Posteriores/efeitos adversos , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal/métodos , Animais , Densidade Óssea/fisiologia , Reabsorção Óssea/patologia , Feminino , Ratos , Ratos Sprague-Dawley , Voo Espacial , Ausência de Peso/efeitos adversos , Microtomografia por Raio-X
19.
Epilepsy Behav ; 37: 16-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24949577

RESUMO

BACKGROUND: Previous studies suggested that one or more HLA alleles participate in the pathogenesis of AED-induced SJS/TEN, but most of these studies focused only on the HLA-B alleles. PURPOSE: The aim of this study was to investigate the pathogenesis of AED-induced SJS/TEN across a broader spectrum of HLA alleles, including the HLA-A, -B and -DRB1 alleles, to further explore the association between each HLA allele and SJS/TEN induced by aromatic AEDs. METHODS: A total of 27 patients exhibiting AED-induced SJS/TEN (16 CBZ-SJS/TEN, seven LTG-SJS/TEN, two PHT-SJS/TEN, and two PB-SJS/TEN patients) and 64 patients who exhibited tolerance to AEDs were recruited. High-resolution HLA genotyping was performed to estimate the prevalence of the HLA-A, -B and -DRB1 alleles for each subject. RESULTS: Fifteen subjects in the SJS/TEN group (12 exhibiting CBZ-SJS/TEN, two exhibiting LTG-SJS, and one exhibiting PB-SJS) carried the HLA-B*15:02 allele, whereas only 4/64 subjects in the AED-tolerant group carried this allele; the carrier rate of HLA-B*15:02 was significantly different between the groups (P<0.001). Nine patients in the SJS/TEN group carried the HLA-DRB1*15:01 allele, while 12/64 subjects in the tolerant group carried this allele; considering that two patients in the SJS/TEN group (one exhibiting LTG-SJS and one exhibiting PB-SJS) were homozygous for this allele, the prevalence of HLA-DRB1*15:01 expression between the two groups was significantly different (P=0.041). Furthermore, the carrier rates of HLA-A*33:03, HLA-B*58:01, and HLA-DRB1*03:01 were lower in the SJS/TEN group compared with the AED-tolerant group. The carrier rates of these alleles between the two groups were significantly different (P=0.009, 0.016, and 0.009, respectively). CONCLUSIONS: The HLA-DRB1*15:01 allele may represent a risk factor for AED-induced SJS/TEN among Han Chinese. The HLA-A*33:03, HLA-B*58:01, and HLA-DRB1*03:01 alleles may be "protectors" against AED-induced SJS/TEN, especially CBZ-SJS/TEN.


Assuntos
Anticonvulsivantes/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Predisposição Genética para Doença , Antígenos HLA-B/genética , Síndrome de Stevens-Johnson/etiologia , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/patologia , Adulto , Alelos , Povo Asiático/genética , Tolerância a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/imunologia , Feminino , Genótipo , Cadeias HLA-DRB1 , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Síndrome de Stevens-Johnson/imunologia
20.
Epilepsy Res ; 108(6): 1041-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24856347

RESUMO

BACKGROUND: The cross-allergic reactions among aromatic antiepileptic drugs (AEDs) are common, but little is known about the genetic mechanisms. PURPOSE: The aim of this study was to investigate the genetic associations of the human leukocyte antigen (HLA) genes with the cross-reactivity of cutaneous adverse drug reactions (cADRs) induced by different aromatic AEDs. METHODS: We reviewed 60 Chinese patients with a history of cADRs induced by an aromatic AED, and which re-challenged other aromatic AEDs as an alternative to the causative AED owing to some particular reasons. According to whether developing another episode of cADRs, these patients were automatically divided into the cross-reactivity group and tolerant control group. High-resolution HLA-A, -B, -DRB1 genotyping were performed for each patient. RESULTS: One out of 10 patients (10%, 1/10) carried the HLA-A*2402 allele in the cross-reactivity group. However, 23 patients (46%, 23/50) carried this allele in the tolerant control group. The difference of the HLA-A*2402 allele between the two groups is statistically significant (P=0.040, OR=0.130, 95% CI: 0.015-1.108). In addition, the frequency differences of other HLA alleles between the two groups, including the HLA-B*1502 allele, did not reach statistical significance (P>0.05). CONCLUSIONS: The HLA genes contribute to the genetic susceptibility of the cross-reactivity of cADRs among aromatic AEDs. Our results suggest that HLA-B*1502 is not a major responsible allele for the cross-reactivity of cADRs to aromatic AEDs, but the HLA-A*2402 allele may be a protective marker for the cross-allergic reactions among aromatic AEDs in Han Chinese. Further studies are warranted to test the potential predictive value of the HLA-A*2402 allele in future.


Assuntos
Anticonvulsivantes/efeitos adversos , Erupção por Droga/genética , Predisposição Genética para Doença , Antígenos HLA/genética , Adolescente , Adulto , Alelos , Povo Asiático/genética , Biomarcadores Farmacológicos , Criança , China , Reações Cruzadas/genética , Feminino , Técnicas de Genotipagem , Antígeno HLA-A24/genética , Antígeno HLA-B15/genética , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Stevens-Johnson/genética , Adulto Jovem
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