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1.
Hum Mol Genet ; 32(3): 462-472, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36001342

RESUMEN

YWHAZ encodes an adapter protein 14-3-3ζ, which is involved in many signaling pathways that control cellular proliferation, migration and differentiation. It has not been definitely correlated to any phenotype in OMIM. To investigate the role of YWHAZ gene in intellectual disability and global developmental delay, we conducted whole-exon sequencing in all of the available members from a large three-generation family and we discovered that a novel variant of the YWHAZ gene was associated with intellectual disability and global developmental delay. This variant is a missense mutation of YWHAZ, p.Lys49Asn/c.147A > T, which was found in all affected members but not found in other unaffected members. We also conducted computational modeling and knockdown/knockin with Drosophila to confirm the role of the YWHAZ variant in intellectual disability. Computational modeling showed that the binding energy was increased in the mutated protein combining with the ligand indicating that the c147A > T variation was a loss-of-function variant. Cognitive defects and mushroom body morphological abnormalities were observed in YWHAZ c.147A > T knockin flies. The YWHAZ knockdown flies also manifested serious cognitive defects with hyperactivity behaviors, which is consistent with the clinical features. Our clinical and experimental results consistently suggested that YWHAZ was a novel intellectual disability pathogenic gene.


Asunto(s)
Discapacidad Intelectual , Malformaciones del Sistema Nervioso , Niño , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/complicaciones , Proteínas 14-3-3/genética , Mutación Missense , Encéfalo , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/complicaciones
2.
Ann Neurol ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38979912

RESUMEN

OBJECTIVE: Most paroxysmal kinesigenic dyskinesia (PKD) cases are hereditary, yet approximately 60% of patients remain genetically undiagnosed. We undertook the present study to uncover the genetic basis for undiagnosed PKD patients. METHODS: Whole-exome sequencing was performed for 106 PRRT2-negative PKD probands. The functional impact of the genetic variants was investigated in HEK293T cells and Drosophila. RESULTS: Heterozygous variants in KCNJ10 were identified in 11 individuals from 8 unrelated families, which accounted for 7.5% (8/106) of the PRRT2-negative probands. Both co-segregation of the identified variants and the significantly higher frequency of rare KCNJ10 variants in PKD cases supported impacts from the detected KCNJ10 heterozygous variants on PKD pathogenesis. Moreover, a KCNJ10 mutation-carrying father from a typical EAST/SeSAME family was identified as a PKD patient. All patients manifested dystonia attacks triggered by sudden movement with a short episodic duration. Patch-clamp recordings in HEK293T cells revealed apparent reductions in K+ currents of the patient-derived variants, indicating a loss-of-function. In Drosophila, milder hyperexcitability phenotypes were observed in heterozygous Irk2 knock-in flies compared to homozygotes, supporting haploinsufficiency as the mechanism for the detected heterozygous variants. Electrophysiological recordings showed that excitatory neurons in Irk2 haploinsufficiency flies exhibited increased excitability, and glia-specific complementation with human Kir4.1 rescued the Irk2 mutant phenotypes. INTERPRETATION: Our study established haploinsufficiency resulting from heterozygous variants in KCNJ10 can be understood as a previously unrecognized genetic cause for PKD and provided evidence of glial involvement in the pathophysiology of PKD. ANN NEUROL 2024.

3.
J Med Genet ; 61(7): 652-660, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38508705

RESUMEN

BACKGROUND: The ZFHX3 gene plays vital roles in embryonic development, cell proliferation, neuronal differentiation and neuronal death. This study aims to explore the relationship between ZFHX3 variants and epilepsy. METHODS: Whole-exome sequencing was performed in a cohort of 378 patients with partial (focal) epilepsy. A Drosophila Zfh2 knockdown model was used to validate the association between ZFHX3 and epilepsy. RESULTS: Compound heterozygous ZFHX3 variants were identified in eight unrelated cases. The burden of ZFHX3 variants was significantly higher in the case cohort, shown by multiple/specific statistical analyses. In Zfh2 knockdown flies, the incidence and duration of seizure-like behaviour were significantly greater than those in the controls. The Zfh2 knockdown flies exhibited more firing in excitatory neurons. All patients presented partial seizures. The five patients with variants in the C-terminus/N-terminus presented mild partial epilepsy. The other three patients included one who experienced frequent non-convulsive status epilepticus and two who had early spasms. These three patients had also neurodevelopmental abnormalities and were diagnosed as developmental epileptic encephalopathy (DEE), but achieved seizure-free after antiepileptic-drug treatment without adrenocorticotropic-hormone/steroids. The analyses of temporal expression (genetic dependent stages) indicated that ZFHX3 orthologous were highly expressed in the embryonic stage and decreased dramatically after birth. CONCLUSION: ZFHX3 is a novel causative gene of childhood partial epilepsy and DEE. The patients of infantile spasms achieved seizure-free after treatment without adrenocorticotropic-hormone/steroids implies a significance of genetic diagnosis in precise treatment. The genetic dependent stage provided an insight into the underlying mechanism of the evolutional course of illness.


Asunto(s)
Epilepsias Parciales , Proteínas de Homeodominio , Espasmos Infantiles , Animales , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Epilepsias Parciales/genética , Epilepsias Parciales/tratamiento farmacológico , Secuenciación del Exoma , Predisposición Genética a la Enfermedad , Proteínas de Homeodominio/genética , Mutación , Espasmos Infantiles/genética , Drosophila
4.
J Biochem Mol Toxicol ; 38(9): e23794, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39163615

RESUMEN

Isoliensinine (ISO), a natural compound, is a bibenzyl isoquinoline alkaloid monomer in lotus seed, which has strong antioxidant and free radical scavenging activities. The oxidative toxicity caused by glutamic acid overdose is one of the important mechanisms of nerve cell injury, and the oxidative toxicity caused by glutamic acid is related to ferroptosis. This study aims to establish a glutamate-induced injury model of mouse hippocampal neurons HT-22 cells, and investigate the protective effect of ISO on the neurotoxicity of glutamate-induced HT-22 cells. The results showed that ISO inhibited glutamate-induced ferroptosis of neuronal cells through nuclear factor E2-related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) signaling pathway. Pretreatment of HT-22 cells with ISO significantly reduced glutamate-induced cell death. Ferroptosis inhibitors have the same effect. ISO inhibited the decrease of mitochondrial membrane potential detection and the increase of iron content induced by glutamate, the increase of malondialdehyde and reactive oxygen species in cytoplasm and lipid, and protected the activities of GPx and superoxide dismutase enzymes. In addition, WB showed that glutamic acid could induce the upregulated expression of long-chain esteryl coA synthase 4 (ACSL4) protein and the downregulated expression of SLC7A11 and GPX4 protein in HT-22 cells, while ISO could prevent the abnormal expression of these proteins induced by glutamic acid. The nuclear translocation of Nrf2 in HT-22 cells was increased, and the expression of downstream heme oxygenase-1 protein was upregulated. In summary, ISO protects HT-22 cells from glutamate-induced ferroptosis through a novel mechanism of the Nrf2/GPX4 signaling pathway.


Asunto(s)
Ferroptosis , Ácido Glutámico , Factor 2 Relacionado con NF-E2 , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Transducción de Señal , Animales , Ferroptosis/efectos de los fármacos , Ratones , Ácido Glutámico/toxicidad , Ácido Glutámico/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Línea Celular , Isoquinolinas/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismo
5.
Brain ; 144(10): 3050-3060, 2021 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-33876820

RESUMEN

The unc-13 homolog B (UNC13B) gene encodes a presynaptic protein, mammalian uncoordinated 13-2 (Munc13-2), which is highly expressed in the brain-predominantly in the cerebral cortex-and plays an essential role in synaptic vesicle priming and fusion, potentially affecting neuronal excitability. However, the functional significance of the UNC13B mutation in human disease is not known. In this study, we screened for novel genetic variants in a cohort of 446 unrelated cases (families) with partial epilepsy without acquired causes by trio-based whole-exome sequencing. UNC13B variants were identified in 12 individuals affected by partial epilepsy and/or febrile seizures from eight unrelated families. The eight probands all had focal seizures and focal discharges in EEG recordings, including two patients who experienced frequent daily seizures and one who showed abnormalities in the hippocampus by brain MRI; however, all of the patients showed a favourable outcome without intellectual or developmental abnormalities. The identified UNC13B variants included one nonsense variant, two variants at or around a splice site, one compound heterozygous missense variant and four missense variants that cosegregated in the families. The frequency of UNC13B variants identified in the present study was significantly higher than that in a control cohort of Han Chinese and controls of the East Asian and all populations in the Genome Aggregation Database (gnomAD). Computational modelling, including hydrogen bond and docking analyses, suggested that the variants lead to functional impairment. In Drosophila, seizure rate and duration were increased by Unc13b knockdown compared to wild-type flies, but these effects were less pronounced than in sodium voltage-gated channel alpha subunit 1 (Scn1a) knockdown Drosophila. Electrophysiological recordings showed that excitatory neurons in Unc13b-deficient flies exhibited increased excitability. These results indicate that UNC13B is potentially associated with epilepsy. The frequent daily seizures and hippocampal abnormalities but ultimately favourable outcome under anti-epileptic therapy in our patients indicate that partial epilepsy caused by UNC13B variant is a clinically manageable condition.


Asunto(s)
Epilepsias Parciales/diagnóstico por imagen , Epilepsias Parciales/genética , Variación Genética/genética , Proteínas del Tejido Nervioso/genética , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Niño , Preescolar , Drosophila , Epilepsias Parciales/fisiopatología , Femenino , Humanos , Masculino , Resultado del Tratamiento
6.
Am J Physiol Endocrinol Metab ; 320(5): E951-E966, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33719588

RESUMEN

Type 2 diabetes mellitus (T2DM) results in compromised bone microstructure and quality, and subsequently increased risks of fractures. However, it still lacks safe and effective approaches resisting T2DM bone fragility. Pulsed electromagnetic fields (PEMFs) exposure has proven to be effective in accelerating fracture healing and attenuating osteopenia/osteoporosis induced by estrogen deficiency. Nevertheless, whether and how PEMFs resist T2DM-associated bone deterioration remain not fully identified. The KK-Ay mouse was used as the T2DM model. We found that PEMF stimulation with 2 h/day for 8 wk remarkably improved trabecular bone microarchitecture, decreased cortical bone porosity, and promoted trabecular and cortical bone material properties in KK-Ay mice. PEMF stimulated bone formation in KK-Ay mice, as evidenced by increased serum levels of bone formation (osteocalcin and P1NP), enhanced bone formation rate, and increased osteoblast number. PEMF significantly suppressed osteocytic apoptosis and sclerostin expression in KK-Ay mice. PEMF exerted beneficial effects on osteoblast- and osteocyte-related gene expression in the skeleton of KK-Ay mice. Nevertheless, PEMF exerted no effect on serum biomarkers of bone resorption (TRAcP5b and CTX-1), osteoclast number, or osteoclast-specific gene expression (TRAP and cathepsin K). PEMF upregulated gene expression of canonical Wnt ligands (including Wnt1, Wnt3a, and Wnt10b), but not noncanonical Wnt5a. PEMF also upregulated skeletal protein expression of downstream p-GSK-3ß and ß-catenin in KK-Ay mice. Moreover, PEMF-induced improvement in bone microstructure, mechanical strength, and bone formation in KK-Ay mice was abolished after intragastric administration with the Wnt antagonist ETC-159. Together, our results suggest that PEMF can improve bone microarchitecture and quality by enhancing the biological activities of osteoblasts and osteocytes, which are associated with the activation of the Wnt/ß-catenin signaling pathway. PEMF might become an effective countermeasure against T2DM-induced bone deterioration.NEW & NOTEWORTHY PEMF improved trabecular bone microarchitecture and suppressed cortical bone porosity in T2DM KK-Ay mice. It attenuated T2DM-induced detrimental consequence on trabecular and cortical bone material properties. PEMF resisted bone deterioration in KK-Ay mice by enhancing osteoblast-mediated bone formation. PEMF also significantly suppressed osteocytic apoptosis and sclerostin expression in KK-Ay mice. The therapeutic potential of PEMF on T2DM-induced bone deterioration was associated with the activation of Wnt/ß-catenin signaling.


Asunto(s)
Enfermedades Óseas Metabólicas/terapia , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Magnetoterapia , Osteoporosis/terapia , Animales , Enfermedades Óseas Metabólicas/etiología , Enfermedades Óseas Metabólicas/genética , Enfermedades Óseas Metabólicas/metabolismo , Huesos/metabolismo , Huesos/efectos de la radiación , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Campos Electromagnéticos , Glucosa/metabolismo , Magnetoterapia/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Osteogénesis/fisiología , Osteogénesis/efectos de la radiación , Osteoporosis/etiología , Osteoporosis/genética , Osteoporosis/metabolismo , Vía de Señalización Wnt/efectos de la radiación , beta Catenina/metabolismo
7.
FASEB J ; 34(2): 3037-3050, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31908035

RESUMEN

Pulsed electromagnetic fields (PEMFs) and whole-body vibration (WBV) are proved to partially preserve bone mass/strength in hindlimb-unloaded and ovariectomized animals. However, the potential age-dependent skeletal response to either PEMF or WBV has not been fully investigated. Moreover, whether the coupled "mechano-electro-magnetic" signals can induce greater osteogenic potential than single stimulation remains unknown. Herein, 5-month-old or 20-month-old rats were assigned to the Control, PEMF, WBV, and PEMF + WBV groups. After 8-week treatment, single PEMF/WBV enhanced bone mass, strength, and anabolism in 5-month-old rats, but not in 20-month-old rats. PEMF + WBV induced greater increase of bone quantity, quality, and anabolism than single PEMF/WBV in young adult rats. PEMF + WBV also inhibited bone loss in elderly rats by primarily improving osteoblast and osteocyte activity, but had no effects on bone resorption. PEMF + WBV upregulated the expression of various canonical Wnt ligands and downstream molecules (p-GSK-3ß and ß-catenin), but had no impacts on noncanonical Wnt5a expression in aged skeleton, revealing the potential involvement of canonical Wnt signaling in bone anabolism of PEMF + WBV. This study not only reveals much weaker responsiveness of aged skeleton to single PEMF/WBV relative to young adult skeleton, but also presents a novel noninvasive approach based on combinatorial treatment with PEMF + WBV for improving bone health and preserving bone quantity/quality (especially for age-related osteoporosis) with stronger anabolic effects.


Asunto(s)
Envejecimiento , Magnetoterapia , Osteoporosis , Esqueleto , Vibración , Animales , Masculino , Osteoporosis/metabolismo , Osteoporosis/fisiopatología , Osteoporosis/terapia , Ratas , Ratas Sprague-Dawley , Esqueleto/metabolismo , Esqueleto/fisiopatología
8.
FASEB J ; 34(2): 2579-2594, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31908007

RESUMEN

The skeleton of type 1 diabetes mellitus (T1DM) has deteriorated mechanical integrity and increased fragility, whereas the mechanisms are not fully understood. Load-induced microdamage naturally occurs in bone matrix and can be removed by initiating endogenous targeted bone remodeling. However, the microdamage accumulation in diabetic skeleton and the corresponding bone remodeling mechanisms remain poorly understood. Herein, streptozotocin-induced T1DM rats and age-matched non-diabetic rats were subjected to daily uniaxial ulnar loading for 1, 4, 7, and 10 days, respectively. The SPECT/CT and basic fuchsin staining revealed significant higher-density spatial accumulation of linear and diffuse microdamage in diabetic ulnae than non-diabetic ulnae. Linear microcracks increased within 10-day loading in diabetic bone, whereas peaked at Day 7 in non-diabetic bone. Moreover, diabetic fatigued ulnae had more severe disruptions of osteocyte canaliculi around linear microcracks. Immunostaining results revealed that diabetes impaired targeted remodeling in fatigued bone at every key stage, including increased apoptosis of bystander osteocytes, decreased RANKL secretion, reduced osteoclast recruitment and bone resorption, and impaired osteoblast-mediated bone formation. This study characterizes microdamage accumulation and abnormal remodeling mechanisms in the diabetic skeleton, which advances our etiologic understanding of diabetic bone deterioration and increased fragility from the aspect of microdamage accumulation and bone remodeling.


Asunto(s)
Remodelación Ósea/fisiología , Resorción Ósea/metabolismo , Diabetes Mellitus/metabolismo , Osteoclastos/metabolismo , Animales , Apoptosis/fisiología , Resorción Ósea/fisiopatología , Masculino , Osteocitos/metabolismo , Ratas Sprague-Dawley , Estrés Mecánico , Cúbito/fisiopatología , Soporte de Peso/fisiología
9.
J Cell Physiol ; 2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-33289098

RESUMEN

Mechanical stretch is known to promote osteoblast differentiation in vitro and accelerate bone regeneration in vivo, whereas the relevant mechanism remains unclear. Recent studies have shown the importance of reciprocal interactions between mammalian target of rapamycin (mTOR) and nuclear factor kappa B (NF-κB; two downstream molecules of Akt) in the regulation of tumor cells. Thus, we hypothesize that mTOR and NF-κB as well as their interconnection play a critical role in mediating stretch-induced osteogenic differentiation in osteoblasts. We herein found that mechanical stretch (10% elongation at six cycles/min) significantly promoted the expression of osteoblast differentiation-related markers (including ALP, BMP2, Col1α, OCN, and Runx2) in osteoblast-like MG-63 cells, accompanied by increased mTOR phosphorylation and NF-κB p65 phosphorylation and nuclear translocation. Blockade of mTOR by antagonist or small interfering RNA suppressed osteogenesis-related gene expression in response to mechanical stretch, whereas inhibition of NF-κB further increased stretch-induced osteoblast differentiation. Moreover, inhibition of mTOR decreased the phosphorylation of NF-κB, and blockade of NF-κB reduced the mTOR activation in MG63 cells under mechanical stretch. Coinhibition of mTOR and NF-κB abolishes the alteration of osteogenic differentiation induced by single mTOR or NF-κB inhibition under mechanical stretch, which is equivalent to the noninhibition level for osteoblasts under mechanical stretch. The expression levels of osteogenic differentiation in osteoblasts after inhibition of Akt were similar to those after co-inhibition of mTOR and NF-κB under mechanical stretch. This study for the first time reveals the reciprocal interconnection between mTOR and NF-κB in osteoblasts under mechanical stretch and indicates that mTOR and NF-κB as well as their interactions play a key role in the regulation of cellular homeostasis of osteoblasts in response to mechanical stretch. These findings are helpful for enriching our basic knowledge of the molecular mechanisms of osteoblast mechanotransduction, and also providing insight into the clinical therapeutic modality associated with mechanical stretch (e.g., distraction osteogenesis).

10.
Cell Biol Int ; 44(1): 216-228, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31448865

RESUMEN

Diabetic patients exhibit significant bone deterioration. Our recent findings demonstrate that mechanical vibration is capable of resisting diabetic bone loss, whereas the relevant mechanism remains unclear. We herein examined the effects of mechanical vibration on the activities and functions of osteocytes (the most abundant and well-recognized mechanosensitive cells in the bone) exposed to high glucose (HG). The osteocytic MLO-Y4 cells were incubated with 50 mM HG for 24 h, and then stimulated with 1 h/day mechanical vibration (0.5 g, 45 Hz) for 3 days. We found that mechanical vibration significantly increased the proliferation and viability of MLO-Y4 cells under the HG environment via the MTT, BrdU, and Cell Viability Analyzer assays. The apoptosis detection showed that HG-induced apoptosis in MLO-Y4 cells was inhibited by mechanical vibration. Moreover, increased cellular area, microfilament density, and anisotropy in HG-incubated MLO-Y4 cells were observed after mechanical vibration via the F-actin fluorescence staining. The real-time polymerase chain reaction and western blotting results demonstrated that mechanical vibration significantly upregulated the gene and protein expression of Wnt3a, ß-catenin, and osteoprotegerin (OPG) and decreased the sclerostin, DKK1, and receptor activator for nuclear factor-κB ligand (RANKL) expression in osteocytes exposed to HG. The enzyme-linked immunosorbent assay assays showed that mechanical vibration promoted the secretion of prostaglandin E2 and OPG, and inhibited the secretion of tumor necrosis factor-α and RANKL in the supernatant of HG-treated MLO-Y4 cells. Together, this study demonstrates that mechanical vibration improves osteocytic architecture and viability, and regulates cytokine expression and secretion in the HG environment, and implies the potential great contribution of the modulation of osteocytic activities in resisting diabetic osteopenia/osteoporosis by mechanical vibration.

11.
Exp Cell Res ; 384(1): 111547, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31472117

RESUMEN

Traumatic brain injury (TBI) is common and often fatal in current times. The role of poly(adenosine diphosphate-ribose) polymerase (PARP)-induced cell death (parthanatos) in TBI has not been well studied. Our past study showed that oxidative stress-induced cell death includes parthanatos by confirming the occurrence of PARP activation and nuclear translocation of apoptosis-inducing factor (AIF). As oxidative stress plays a key role in pathological progression after TBI, we believe TBI may also be alleviated by the expression of Iduna, which is the only known endogenous regulator of parthanatos. Thus, a transection model in HT-22 cells was established for present study. Downregulation of Iduna aggravated the cell damage caused by mechanical cell injury, whereas upregulation of Iduna reduced mitochondrial dysfunction induced by mechanical cell injury but exerted no effect on apoptosis associated with mitochondrial dysfunction. By contrast, Iduna prevented parthanatos by reducing PARP activation and nuclear translocation of AIF. We also investigated 2 novel p53-MDM2 pathway inhibitors, AMG 232 and Nutlin-3, which substantially reduced the protective effects of Iduna. These findings indicate that Iduna might prevent TBI by specifically inhibiting parthanatos and promoting mitochondrial function, with the p53-MDM2 pathway playing a critical role.


Asunto(s)
Parthanatos/fisiología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Transducción de Señal/fisiología , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Apoptosis/fisiología , Factor Inductor de la Apoptosis/metabolismo , Muerte Celular/fisiología , Línea Celular , Regulación hacia Abajo/fisiología , Ratones , Mitocondrias/metabolismo , Estrés Oxidativo/fisiología , Poli(ADP-Ribosa) Polimerasas/metabolismo
12.
J Cell Physiol ; 234(7): 10588-10601, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30422320

RESUMEN

Growing evidence has shown that pulsed electromagnetic fields (PEMF) can modulate bone metabolism in vivo and regulate the activities of osteoblasts and osteoclasts in vitro. Osteocytes, accounting for 95% of bone cells, act as the major mechanosensors in bone for transducing external mechanical signals and producing cytokines to regulate osteoblastic and osteoclastic activities. Targeting osteocytic signaling pathways is becoming an emerging therapeutic strategy for bone diseases. We herein systematically investigated the changes of osteocyte behaviors, functions, and its regulation on osteoclastogenesis in response to PEMF. The osteocyte-like MLO-Y4 cells were exposed to 15 Hz PEMF stimulation with different intensities (0, 5, and 30 Gauss [G]) for 2 hr. We found that the cell apoptosis and cytoskeleton organization of osteocytes were regulated by PEMF with an intensity-dependent manner. Moreover, PEMF exposure with 5 G significantly inhibited apoptosis-related gene expression and also suppressed the gene and protein expression of the receptor activator of nuclear factor κB ligand/osteoprotegerin (RANKL/OPG) ratio in MLO-Y4 cells. The formation, maturation, and osteoclastic bone-resorption capability of in vitro osteoclasts were significantly suppressed after treated with the conditioned medium from PEMF-exposed (5 G) osteocytes. Our results also revealed that the inhibition of osteoclastic formation, maturation, and bone-resorption capability induced by the conditioned medium from 5 G PEMF-exposed osteocytes was significantly attenuated after abrogating primary cilia in osteocytes using the polaris siRNA transfection. Together, our findings highlight that PEMF with 5 G can inhibit cellular apoptosis, modulate cytoskeletal distribution, and decrease RANKL/OPG expression in osteocytes, and also inhibit osteocyte-mediated osteoclastogenesis, which requires the existence of primary cilia in osteocytes. This study enriches our basic knowledge for further understanding the biological behaviors of osteocytes and is also helpful for providing a more comprehensive mechanistic understanding of the effect of electromagnetic stimulation on bone and relevant skeletal diseases (e.g., bone fracture and osteoporosis).


Asunto(s)
Resorción Ósea/genética , Osteogénesis/genética , Osteoprotegerina/genética , Ligando RANK/genética , Animales , Apoptosis/genética , Resorción Ósea/patología , Resorción Ósea/terapia , Células Cultivadas , Cilios/genética , Cilios/efectos de la radiación , Citoesqueleto/genética , Campos Electromagnéticos , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Ratones , Osteoclastos/efectos de la radiación , Osteocitos/efectos de la radiación , Osteogénesis/efectos de la radiación , Transducción de Señal/genética
13.
Pak J Med Sci ; 35(1): 257-261, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30881434

RESUMEN

BACKGROUND AND OBJECTIVE: Colorectal serrated polyp is considered as histologically heterogeneous lesions with malignant potential. The aim of the study was to evaluate the endoscopic, clinic and pathologic characteristics of colorectal serrated polyps. METHODS: The endoscopic, clinic and pathologic characteristics of 52 cases with colorectal serrated polyps between January 2014 and May 2018 in our hospital were analyzed. retrospectively. RESULTS: The prevalence of serrated polyps was 0.39% (52/13,346). The proportions of hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA) of all serrated polyps were 61.5%, 17.3%, and 21.2%, respectively, which showed a lower proportion of TSA and SSA/P and a higher proportion of HP. CONCLUSIONS: The overall detection rate of colorectal serrated polyps was relatively low, and it is necessary to discriminate between SSAPs and HPs during endoscopic examination because of the malignant potential.

14.
Cell Biol Int ; 42(10): 1410-1422, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30022568

RESUMEN

The effects of load-induced interstitial fluid shear stress (FSS) on instantaneous signaling response of osteocytes (e.g., calcium signaling) have been well documented. FSS can also initiate the release of many important messenger molecules of osteocytes (e.g., ATP and PGE2 ). However, the effects of FSS on cellular function and bone metabolism-modulating cytokine expression of osteocytes have not been fully identified (some inconsistent/conflicting results have been documented). Herein, osteocyte-like MLO-Y4 cells were stimulated with 1 Pa, 2-h FSS, and the effects of FSS on cellular morphology, cytoskeletal microstructure, biological activity, and gene and protein expression of important cytokines were investigated. SEM and cytoskeleton staining revealed that FSS induced well-organized cytoskeleton and increased filopodia processes. The osteocytic viability was sustained and apoptosis was inhibited via flow cytometry. FSS promoted Wnt3a and ß-catenin gene and protein expression in 0-, 3-, and 6-h (sample collection time post FSS) groups. The FSS-stimulated cells in the 3-h group exhibited more significant effects on the promotion of OCN and Cx43 and inhibition of DKK1 and SOST expression than the 0- and 6-h groups. The 3-h group with FSS stimulation also showed the most prominent effects on suppressing RANKL and RANKL/OPG gene and protein expression. This study revealed a direct regulatory effect of FSS on osteocytic morphology and apoptotic characteristics, and showed that osteocyte-secreted bone metabolism-modulating molecule expression was regulated by FSS in a time-dependent manner. This study not only enriches our basic knowledge for understanding osteocytic mechanotransduction, but also provides important evidence for more scientific experimental design.


Asunto(s)
Mecanotransducción Celular/fisiología , Osteocitos/fisiología , Animales , Línea Celular , Supervivencia Celular/fisiología , Citocinas/genética , Citocinas/fisiología , Citoesqueleto/fisiología , Regulación de la Expresión Génica/fisiología , Hidrodinámica , Ratones , Microtúbulos/metabolismo , Osteocitos/citología , Transducción de Señal , Estrés Mecánico , Vía de Señalización Wnt/fisiología , beta Catenina/fisiología
16.
Bioelectromagnetics ; 38(1): 63-77, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27859405

RESUMEN

Periodontal ligament stem cells (PDLSCs) have been confirmed to have self-renewal capacity and multidifferentiation potential and are good candidates for periodontal tissue regeneration. Pulsed electromagnetic field (PEMF) has been demonstrated to promote osteogenesis in non-union fractures, partly by regulating mesenchymal stem cells or osteoblast activity. However, there is no report about the osteo-inductive effect of PEMF stimulation on human PDLSCs (hPDLSCs). Thus, we tested the hypothesis that PEMF biophysical stimulation alone has an influence on the proliferation and osteogenic differentiation of hPDLSCs. To detect the osteo-inductive potential of bone morphogenetic protein (BMP9), we transfected the STRO-1+ /CD146+ hPDLCSs with BMP9-expressing recombinant adenoviruses. We examined the proliferation and osteogenic differentiation of hPDLSCs treated with either PEMF (15 Hz, 1 h daily, different intensities), or BMP9, or both stimuli. Cell counting kit-8 (CCK-8) assay showed that PEMF of different intensities had no effect on the proliferation of hPDLSCs and did not enhance the proliferative capability of BMP9-transfected cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting showed that the combination of both PEMFs (1.8 or 2.4 mT) and BMP9 stimulation had a synergistic effect on early and intermediate osteogenic genes and protein expressions of runt-related transcription factor 2, alkaline phosphatase, osteopontin, and late mineralized extracellular matrix formation in hPDLSCs. Bioelectromagnetics. 38:63-77, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Campos Electromagnéticos , Factor 2 de Diferenciación de Crecimiento/farmacología , Osteogénesis/efectos de los fármacos , Ligamento Periodontal/citología , Células Madre/efectos de los fármacos , Células Madre/efectos de la radiación , Adolescente , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Niño , Matriz Extracelular/metabolismo , Humanos , Minerales/metabolismo , Células Madre/citología , Regulación hacia Arriba/efectos de los fármacos
17.
Bioelectromagnetics ; 38(8): 602-612, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28741320

RESUMEN

Pulsed electromagnetic fields (PEMF) have been proven to be effective for promoting bone mass and regulating bone turnover both experimentally and clinically. However, the exact mechanisms for the regulation of PEMF on osteoclastogenesis as well as optical exposure parameters of PEMF on inhibiting osteoclastic activities and functions remain unclear, representing significant limitations for extensive scientific application of PEMF in clinics. In this study, RAW264.7 cells incubated with RANKL were exposed to 15 Hz PEMF (2 h/day) at various intensities (0.5, 1, 2, and 3 mT) for 7 days. We demonstrate that bone resorbing capacity was significantly decreased by 0.5 mT PEMF mainly by inhibiting osteoclast formation and maturation, but enhanced at 3 mT by promoting osteoclast apoptosis. Moreover, gene expression of RANK, NFATc1, TRAP, CTSK, BAX, and BAX/BCL-2 was significantly decreased by 0.5 mT PEMF, but increased by 3 mT. Our findings reveal a significant intensity window for low-intensity PEMF in regulating bone resorption with diverse nature for modulating osteoclastogenesis and apoptosis. This study not only enriches our basic knowledge for the regulation of PEMF in osteoclastogenesis, but also may lead to more efficient and scientific clinical application of PEMF in regulating bone turnover and inhibiting osteopenia/osteoporosis. Bioelectromagnetics. 38:602-612, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Apoptosis/efectos de la radiación , Resorción Ósea/patología , Campos Electromagnéticos , Osteoclastos/citología , Osteoclastos/efectos de la radiación , Ligando RANK/farmacología , Animales , Citoesqueleto/metabolismo , Citoesqueleto/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Regulación de la Expresión Génica/efectos de la radiación , Ratones , Osteogénesis/efectos de la radiación , Células RAW 264.7
18.
Clin Invest Med ; 39(5): E150-E160, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27805898

RESUMEN

PURPOSE: Staging liver cirrhosis is essential for the management of chronic hepatitis C (CHC). The current meta-analysis evaluated the accuracy of transient elastography for detecting liver cirrhosis in patients with CHC. METHODS: Either prospective or retrospective studies, including cohort and cross sectional studies, in patients diagnosed with chronic hepatitis C, as assessed by transient elastography, were searched from Medline, Cochrane, EMBASE, and Google Scholar databases until March 3, 2015, using the terms "transient elastography, chronic hepatitis C and liver cirrhosis". The primary outcome analyzed was the diagnostic performance, which included sensitivity, specificity, diagnostic odds ratio and area under the receiver-operating characteristic (ROC) curve. RESULTS: Data from 24 articles included in the meta-analysis demonstrated high sensitivity (84%) and specificity (90%) of transient elastography (TE) for assessing liver cirrhosis patients with HCV. Subgroup analysis of patients by underlying diseases revealed a sensitivity and specificity of 91% and 92% (HCV alone), 100% and 75% (HCV-liver transplant), 83.6% and 89.7% (HIV/HCV co-infection) and 97.1% and 90.7% (recurrent CHC after liver transplantation). The pooled diagnostic odds ratio was 61.57 (95% CI, 39.5 - 96.00) and the area under the summary ROC curves was 0.952 ± 0.008, suggesting high diagnostic accuracy of TE. CONCLUSION: Transient elastography can accurately predict liver cirrhosis in patients with hepatitis C, with a sensitivity and specificity of 84% and 90%, respectively. The present results further validate the utility of TE in staging liver cirrhosis in chronic HCV infections.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Hepatitis C Crónica/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
19.
Endocr J ; 63(4): 381-8, 2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-26842591

RESUMEN

The aim of our study is to establish the reference intervals (RIs) of thyroid hormones in a previously iodine-deficient area but presently more than iodine-adequate area of Western China, and also to investigate the factors which affect thyroid function. The cross-sectional study conducted in Xi'an, was based on 2007-2008 China National Diabetes and Metabolic Disorders Survey. Among 1286 participating adults, 717 were finally included as reference population. Thyrotropin (TSH), total triiodothyronine (T3), free triiodothyronine (FT3), total thyroxine (T4), free thyroxine (FT4), thyroperoxidase antibody (TPO-Ab) and thyroglobulin antibody (Tg-Ab) were measured. Thyroid ultrasound examination was also performed. The present study established the new RIs of serum TSH (0.43-5.51 mIU/L), FT4 (11.0-20.4 pmol/L), FT3 (3.63-5.73 pmol/L), T4 (67.8-157 mmol/L) and T3 (1.08-2.20 mmol/L), which were different from the data provided by the manufacturers. Significant differences among all the age groups were observed in FT3, but neither in TSH nor in FT4. The TSH levels in adults with pathologic ultrasonography results or positive thyroid autoantibody were significantly higher than those in reference adults. Our present results provide valuable references for the diagnosis of thyroid diseases in population of Western China. Considering that most inland areas of China have faced the challenge of the transition from iodine deficiency to adequacy or more than adequacy, we recommend physicians utilize our RIs to determine thyroid diseases in the similar areas with Xi'an in China.


Asunto(s)
Hipotiroidismo/rehabilitación , Yodo/deficiencia , Pruebas de Función de la Tiroides/normas , Hormonas Tiroideas/sangre , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Femenino , Humanos , Hipotiroidismo/sangre , Hipotiroidismo/epidemiología , Yodo/administración & dosificación , Masculino , Persona de Mediana Edad , Valores de Referencia , Cloruro de Sodio Dietético/administración & dosificación , Encuestas y Cuestionarios , Adulto Joven
20.
Bioelectromagnetics ; 37(3): 152-162, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26891468

RESUMEN

Substantial evidence indicates that pulsed electromagnetic fields (PEMF) could accelerate fracture healing and enhance bone mass, whereas the unclear mechanism by which PEMF stimulation promotes osteogenesis limits its extensive clinical application. In the present study, effects and potential molecular signaling mechanisms of PEMF on in vitro osteoblasts were systematically investigated. Osteoblast-like MC3T3-E1 cells were exposed to PEMF burst (0.5, 1, 2, or 6 h/day) with 15.38 Hz at various intensities (5 Gs (0.5 mT), 10 Gs (1 mT), or 20 Gs (2 mT)) for 3 consecutive days. PEMF stimulation at 20 Gs (2 mT) for 2 h/day exhibited most prominent promotive effects on osteoblastic proliferation via Cell Counting kit-8 analyses. PEMF exposure induced well-organized cytoskeleton, and promoted formation of extracellular matrix mineralization nodules. Significantly increased proliferation-related gene expressions at the proliferation phase were observed after PEMF stimulation, including Ccnd 1 and Ccne 1. PEMF resulted in significantly increased gene and protein expressions of alkaline phosphatase and osteocalcin at the differentiation phase of osteoblasts rather than the proliferation phase via quantitative reverse transcription polymerase chain reaction and Western blotting analyses. Moreover, PEMF upregulated gene and protein expressions of collagen type 1, Runt-related transcription factor 2 and Wnt/ß-catenin signaling (Wnt1, Lrp6, and ß-catenin) at proliferation and differentiation phases. Together, our present findings highlight that PEMF stimulated osteoblastic functions through a Wnt/ß-catenin signaling-associated mechanism and, hence, regulates downstream osteogenesis-associated gene/protein expressions. Bioelectromagnetics. 37:152-162, 2016. © 2016 Wiley Periodicals, Inc.

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