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Lymphedema, a prevalent, multifaceted, and chronic ailment, is mainly managed through physical manipulation and suffers from a lack of specific pharmacological treatments. Secondary lymphedema is mainly caused by impaired lymphatic drainage. Therapeutic lymphangiogenesis is a promising strategy in the treatment of lymphedema. Andrographolide, a natural product from Andrographis paniculata, is unknown whether andrographolide promotes lymphangiogenesis to improve secondary lymphedema. By using the murine tail lymphedema model, we demonstrated that andrographolide can reduce the thickness of subcutaneous tissue in the mice's tail and enhance lymphatic drainage. Moreover, immunofluorescence staining showed that the number of capillary lymphatic vessels in the ANDRO25 group was significantly more than that in the ANDRO50 and Model groups. Near-infrared lymphography images showed that highlighted sciatic lymph nodes could be seen in the ANDRO25 and ANDRO50 groups. In vitro, andrographolide could promote the proliferation and migration of LEC. In conclusion, andrographolide enhanced the recovery of lymphatic vessels, and promoted lymphatic drainage in the murine tail lymphedema model by promoting the proliferation of lymphatic endothelial cells, thereby reducing the symptoms of lymphedema. This suggested andrographolide may be used as a potential therapeutic drug or medical food ingredient to help patients with secondary lymphedema.
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Diterpenos , Linfangiogênese , Vasos Linfáticos , Linfedema , Diterpenos/farmacologia , Animais , Linfangiogênese/efeitos dos fármacos , Linfedema/tratamento farmacológico , Linfedema/patologia , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/patologia , Camundongos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , HumanosRESUMO
Human serum albumin (HSA) is the most abundant protein in human blood plasma. It plays a critical role in the native transportation of numerous drugs, metabolites, nutrients, and small molecules. HSA has been successfully used clinically as a noncovalent carrier for insulin (e.g., Levemir), GLP-1 (e.g., Liraglutide), and paclitaxel (e.g., Abraxane). Site-specific bioconjugation strategies for HSA only would greatly expand its role as the biocompatible, non-toxic platform for theranostics purposes. Using the enabling one-bead one-compound (OBOC) technology, we generated combinatorial peptide libraries containing myristic acid, a well-known binder to HSA at Sudlow I and II binding pockets, and an acrylamide. We then used HSA as a probe to screen the OBOC myristylated peptide libraries for reactive affinity elements (RAEs) that can specifically and covalently ligate to the lysine residue at the proximity of these pockets. Several RAEs have been identified and confirmed to be able to conjugate to HSA covalently. The conjugation can occur at physiological pH and proceed with a high yield within 1 h at room temperature. Tryptic peptide profiling of derivatized HSA has revealed two lysine residues (K225 and K414) as the conjugation sites, which is much more specific than the conventional lysine labeling strategy with N-hydroxysuccinimide ester. The RAE-driven site-specific ligation to HSA was found to occur even in the presence of other prevalent blood proteins such as immunoglobulin or whole serum. Furthermore, these RAEs are orthogonal to the maleimide-based conjugation strategy for Cys34 of HSA. Together, these attributes make the RAEs the promising leads to further develop in vitro and in vivo HSA bioconjugation strategies for numerous biomedical applications.
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Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica Humana/química , Albumina Sérica/metabolismo , Lisina/metabolismo , Biblioteca de Peptídeos , Peptídeos/metabolismo , Ligação ProteicaRESUMO
Theta oscillations in the hippocampus have many behavioral correlates, with the magnitude and vigor of ongoing movement being the most salient. Many consider correlates of locomotion with hippocampal theta to be a confound in delineating theta contributions to cognitive processes. Theory and empirical experiments suggest theta-movement relationships are important if spatial navigation is to support higher cognitive processes. In the current study, we tested if variations in speed modulation of hippocampal theta can predict spatial learning rates in the water maze. Using multi-step regression, we find that the magnitude and robustness of hippocampal theta frequency versus speed scaling can predict water maze learning rates. Using a generalized linear model, we also demonstrate that speed and water maze learning are the best predictors of hippocampal theta frequency and amplitude. Our findings suggest movement-speed correlations with hippocampal theta frequency may be actively used in spatial learning.
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Navegação Espacial , Ritmo Teta , Hipocampo , Aprendizagem em Labirinto , Aprendizagem EspacialRESUMO
Graphene nanoribbons will be essential components in future graphene nanoelectronics. However, in typical nanoribbons produced from lithographically patterned exfoliated graphene, the charge carriers travel only about ten nanometres between scattering events, resulting in minimum sheet resistances of about one kilohm per square. Here we show that 40-nanometre-wide graphene nanoribbons epitaxially grown on silicon carbide are single-channel room-temperature ballistic conductors on a length scale greater than ten micrometres, which is similar to the performance of metallic carbon nanotubes. This is equivalent to sheet resistances below 1 ohm per square, surpassing theoretical predictions for perfect graphene by at least an order of magnitude. In neutral graphene ribbons, we show that transport is dominated by two modes. One is ballistic and temperature independent; the other is thermally activated. Transport is protected from back-scattering, possibly reflecting ground-state properties of neutral graphene. At room temperature, the resistance of both modes is found to increase abruptly at a particular length--the ballistic mode at 16 micrometres and the other at 160 nanometres. Our epitaxial graphene nanoribbons will be important not only in fundamental science, but also--because they can be readily produced in thousands--in advanced nanoelectronics, which can make use of their room-temperature ballistic transport properties.
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CONTEXT: Cordyceps sinensis has been used in traditional Chinese medicine for thousands of years. It has been demonstrated to have a variety of biological activities, and an extract of it has been demonstrated to possess a protective effect in occlusion-induced focal cerebral ischemia of the middle cerebral artery in rats. It could be explored as an agent for treatment of ischemic stroke, and the mechanisms need to be studied further. OBJECTIVE: The study intended to investigate the protective effects of the Cordyceps sinensis oral liquid (CSOL) against damage induced by oxygen and glucose deprivation (OGD) in SH-SY5Y cells. DESIGN ⢠The research team designed an in vitro study. SETTING: The study occurred at the Naval Medical Research Institute in Shanghai, China. INTERVENTION: SH-SY5Y cells were exposed to CSOL in doses of 0.01, 0.03, 0.10, 0.30, and 1.00 mg/mL, creating 5 intervention groups. The OGD condition was induced by transfer of the cells from high-glucose Dulbecco's Modified Eagle's medium (DMEM) in a box gassed with air containing 5% CO2 to glucose-free DMEM in a box gassed with 94% N2, 5% CO2, and 1% O2. Like the cells for the interventions groups, the cells for a model group were cultured with high-glucose DMEM and were transferred to the OGD, but they received no dose of COSL. Cells in a control group were cultured with high-glucose DMEM, were not transferred to the OGD condition, and did not receive any dose of COSL. OUTCOME MEASURES: Cell viability was assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The apoptosis and the mitochondrial membrane potential (MMP) were detected by flow cytometry, and the protein expression of caspase-3 was observed by western blot. RESULTS: After exposure to OGD, the cell viability of cells treated with 0.01, 0.03, 0.10, 0.30, and 1.00 mg/mL of CSOL increased in a dose-effect relationship. Compared with the cells in the model group, the treatment of CSOL at all the experimental concentrations significantly inhibited both the cell apoptosis (P < .01) and the capase-3 activation (P < .01). The MMP dissipation in the cells of the model group increased significantly compared with those of the control group (P < .01). The treatment with all doses of CSOL significantly inhibited the MMP dissipation (P < .01). CONCLUSIONS: CSOL protects against the damage induced by OGD through inhibiting the mitochondrial apoptosis pathway in SH-SY5Y cells.
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Apoptose/efeitos dos fármacos , Produtos Biológicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cordyceps , Glucose/metabolismo , Oxigênio/metabolismo , Produtos Biológicos/química , Hipóxia Celular , Linhagem Celular Tumoral , HumanosRESUMO
Normal bone turnover requires tight coupling of bone resorption and bone formation to preserve bone quantity and structure. With aging and during several pathological conditions, this coupling breaks down, leading to either net bone loss or excess bone formation. To preserve or restore normal bone metabolism, it is crucial to determine the mechanisms by which osteoclasts and osteoblast precursors interact and contribute to coupling. We showed that osteoclasts produce the chemokine sphingosine 1-phosphate (S1P), which stimulates osteoblast migration. Thus, osteoclast-derived S1P may recruit osteoblasts to sites of bone resorption as an initial step in replacing lost bone. In this study we investigated the mechanisms by which S1P stimulates mesenchymal (skeletal) cell chemotaxis. S1P treatment of mesenchymal (skeletal) cells activated RhoA GTPase, but this small G protein did not contribute to migration. Rather, two S1P receptors, S1PR1 and S1PR2, coordinately promoted migration through activation of the JAK/STAT3 and FAK/PI3K/AKT signaling pathways, respectively. These data demonstrate that the chemokine S1P couples bone formation to bone resorption through activation of kinase signaling pathways.
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Células-Tronco Mesenquimais/citologia , Receptores de Lisoesfingolipídeo/metabolismo , Animais , Reabsorção Óssea , Movimento Celular , Células Cultivadas/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Osteoblastos/citologia , Osteogênese , Transdução de Sinais , Receptores de Esfingosina-1-Fosfato , Proteínas rho de Ligação ao GTP/metabolismoRESUMO
After the pioneering investigations into graphene-based electronics at Georgia Tech, great strides have been made developing epitaxial graphene on silicon carbide (EG) as a new electronic material. EG has not only demonstrated its potential for large scale applications, it also has become an important material for fundamental two-dimensional electron gas physics. It was long known that graphene mono and multilayers grow on SiC crystals at high temperatures in ultrahigh vacuum. At these temperatures, silicon sublimes from the surface and the carbon rich surface layer transforms to graphene. However the quality of the graphene produced in ultrahigh vacuum is poor due to the high sublimation rates at relatively low temperatures. The Georgia Tech team developed growth methods involving encapsulating the SiC crystals in graphite enclosures, thereby sequestering the evaporated silicon and bringing growth process closer to equilibrium. In this confinement controlled sublimation (CCS) process, very high-quality graphene is grown on both polar faces of the SiC crystals. Since 2003, over 50 publications used CCS grown graphene, where it is known as the "furnace grown" graphene. Graphene multilayers grown on the carbon-terminated face of SiC, using the CCS method, were shown to consist of decoupled high mobility graphene layers. The CCS method is now applied on structured silicon carbide surfaces to produce high mobility nano-patterned graphene structures thereby demonstrating that EG is a viable contender for next-generation electronics. Here we present for the first time the CCS method that outperforms other epitaxial graphene production methods.
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The maximum oscillation frequency (fmax) quantifies the practical upper bound for useful circuit operation. We report here an fmax of 70 GHz in transistors using epitaxial graphene grown on the C-face of SiC. This is a significant improvement over Si-face epitaxial graphene used in the prior high-frequency transistor studies, exemplifying the superior electronics potential of C-face epitaxial graphene. Careful transistor design using a high κ dielectric T-gate and self-aligned contacts further contributed to the record-breaking fmax.
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It is feasible to improve the photodegradation efficiency of organic pollutants by metal-organic frameworks (MOF)-based semiconductors via ligand engineering. In this work, three (Fe/Co)-XBDC-based MOFs were synthesized by introducing different ortho-functional groups X (X = -H, -NO2, -NH2) next to the carboxyl group of the organic ligand (i.e., terephthalic acid). The analysis focused on the influence mechanism of the adjacent functional group effect of the ligand on the physicochemical properties of the material and the actual photodegradation activity of TC. Multiple pieces of evidences suggested that the differences in electron-induced and photocharge-transfer mechanisms of the above ortho functional groups affect the crystal morphology and photocatalytic activity of FeCo-MOF during pyrolysis. Interestingly, (Fe/Co)-NH2BDC exhibited the highest photocatalytic activity under neutral conditions. The results of density functional theory show that the introduction of a strong donor-NH2 group can enhance light absorption and act as an "electron pump" to supply electrons to the iron center, accelerating the separation and efficient transport of photogenerated carriers on the ligand-metal bridge. In conclusion, this study is a proposal for a strategy of structural regulation for the enhancement of the catalytic activity of (Fe/Co)-MOFs in the photodegradation of TC.
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Compostos Heterocíclicos , Estruturas Metalorgânicas , Ligantes , Tetraciclina , Antibacterianos , ElétronsRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Ligusticum chuanxiong Hort (LCH), with the accepted name of Ligusticum striatum DC in "The Plant List" database, is a widely used ethnomedicine in treating ischemic stroke, and borneol (BO) is usually prescribed with LCH for better therapy. Our previous study confirmed their synergistic effect on neurogenesis against cerebral ischemia. However, the underlying mechanism is still unclear. AIM OF THE STUDY: More and more evidence indicated that astrocytes (ACs) might be involved in the modulation of neurogenesis via polarization reaction. The study was designed to explore the synergic mechanism between LCH and BO in promoting astrocyte-mediated neurogenesis. MATERIALS AND METHODS: After primary cultures and identifications of ACs and neural stem cells (NSCs), the oxygen-glucose deprivation (OGD) model and the concentrations of LCH and BO were optimized. After the OGD-injured ACs were treated by LCH, BO, and their combination, the conditioned mediums were used to culture the OGD-injured NSCs. The proliferation, migration, and differentiation of NSCs were assessed, and the secretions of BDNF, CNTF, and VEGF from ACs were measured. Then the expressions of C3 and PTX3 were detected. Moreover, the mice were performed a global cerebral ischemia/reperfusion model and treated with LCH and (or) BO. After the assessments of Nissl staining, the expressions of Nestin, DCX, GFAP, C3, PTX3, p65 and p-p65 were probed. RESULTS: The most appropriate duration of OGD for the injury of both NSCs and ACs was 6 h, and the optimized concentrations of LCH and BO were 1.30 µg/mL and 0.03 µg/mL, respectively. The moderate OGD environment induced NSCs proliferation, migration, astrogenesis, and neurogenesis, increased the secretions of CNTF and VEGF from ACs, and upregulated the expressions of C3 and PTX3. For the ACs, LCH further increased the secretions of BDNF and CNTF, enhanced PTX3 expression, and reduced C3 expression. Additionally, the conditioned medium from LCH-treated ACs further enhanced NSC proliferation, migration, and neurogenesis. The in vivo study showed that LCH markedly enhanced the Nissl score and neurogenesis, and decreased astrogenesis which was accompanied by downregulations of C3, p-p65, and p-p65/p65 and upregulation of PTX3. BO not only decreased the expression of C3 in ACs both in vitro and in vivo but also downregulated p-p65 and p-p65/p65 in vivo. Additionally, BO promoted the therapeutic effect of LCH for most indices. CONCLUSION: A certain degree of OGD might induce ACs to stimulate the proliferation, astrogenesis, and neurogenesis of NSCs. LCH and BO exhibited a marked synergy in promoting ACs-mediated neurogenesis and reducing astrogenesis, in which LCH played a dominant role and BO boosted the effect of LCH. The mechanism of LCH might be involved in switching the polarization of ACs from A1 to A2, while BO preferred to inhibit the formation of A1 phenotype via downregulating NF-κB pathway.
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Isquemia Encefálica , Canfanos , Ligusticum , Camundongos , Animais , Astrócitos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Ciliar/metabolismo , Fator Neurotrófico Ciliar/farmacologia , Fator Neurotrófico Ciliar/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neurogênese , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto CerebralRESUMO
Extracellular vesicles (EVs) are key mediators of cell-cell communication and are involved in transferring specific biomolecular cargo to recipient cells to regulate their physiological functions. A major challenge in the understanding of EV function in vivo is the difficulty ascertaining the origin of the EV particles. The recent development of the "Snorkel-tag", which includes EV-membrane-targeted CD81 fused to a series of extra-vesicular protein tags, can be used to mark EVs originating from a specific source for subsequent isolation and characterization. We developed an in vivo mouse model, termed "CAGS-Snorkel", which expresses the Snorkel-tag under the control of the Cre-lox system, and crossed this mouse with either Prx1-Cre (mesenchymal progenitors) or Ocn-Cre (osteoblasts/osteocytes) and isolated Snorkel-tagged EVs from the mouse bone marrow plasma using a magnetic bead affinity column. miRNA-sequencing was performed on the isolated EVs, and although similar profiles were observed, a few key miRNAs involved in bone metabolism (miR-106b-5p, miRs-19b-3p and miRs-219a-5p) were enriched in the Ocn-derived relative to the Prx1-derived EV subpopulations. To characterize the effects of these small EVs on a bone cell target, cultured mouse bone marrow stromal cells (mBMSCs) were treated with Prx1 or Ocn EVs, and mRNA-sequencing was performed. Pathways involved in ossification, bone development and extracellular matrix interactions were regulated by both EV subpopulations, whereas a few pathways including advanced glycation end-products (AGE) signaling, were uniquely regulated in the Ocn EV subpopulation, underlying important biological effects of specific EV subpopulations within the bone marrow microenvironment. These data demonstrate that EV isolation in vivo using the CAGS-Snorkel mouse model is a useful tool in characterizing the cargo and understanding the biology of tissue-specific EVs. Moreover, while bone mesenchymal cell populations share a common EV secretory profile, we uncover key differences based on the stage of osteoblastic differentiation that may have important biological consequences.
Extracellular vesicles (EVs) are small, lipid-based particles that are produced by all cells in the body, and function as a method of communication among different cells in a particular microenvironment. However, identification of the source of the EVs is difficult following export from the cell which the EV is produced. To facilitate the identification and characterization of the active molecules contained within EVs from a particular cell-type, we developed a new mouse model (CAGS-Snorkel) which allows for identification of the EV source cell using specific protein molecules on the EVs in only one particular cell- or tissue-type. As a proof-of-principle, we compared the microRNA EV cargo in cells from early bone cell progenitors and mature bone cells in the bone marrow microenvironment. We find that a number of microRNAs, molecules involved in the function and regulation of cellular processes, are expressed both in common and specifically within those two cell types. Notably, when purified EV subpopulations from these cell types were used to treat bone cell cultures, we find both common and unique gene expression and molecular pathway profiles. This work describes a new mouse model that will be useful in understanding how EVs function to carry important cellular information.
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Secondary lymphedema is a chronic and incurable disease lacking satisfactory therapeutic drugs. It primarily results from lymphatic vessel dysfunction resulting from factors such as tumor-related surgery, injury, or infection. Promoting lymphangiogenesis and lymphatic vessel remodeling is crucial for restoring tissue fluid drainage and treating secondary lymphedema. In this study, we discovered that the oral administration of a type-II arabinogalactan (CAPW-1, molecular weight: 64 kDa) significantly promoted lymphangiogenesis and alleviated edema in mice with secondary lymphedema. Notably, the tail diameter of the CAPW-1200 group considerably decreased in comparison to that of the lymphedema group, with an average diameter difference reaching 0.98 mm on day 14. CAPW-1 treatment also reduced the average thickness of the subcutaneous area in the CAPW-1200 group to 0.37 mm (compared with 0.73 mm in the lymphedema group). It also facilitated the return of injected indocyanine green (ICG) from the tail tip to the sciatic lymph nodes, indicating that CAPW-1 promoted lymphatic vessel remodeling at the injury site. In addition, CAPW-1 enhanced the proliferation and migration of lymphatic endothelial cells. This phenomenon was associated with the activation of the toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathway, thereby promoting the expression of vascular endothelial growth factor-C (VEGF-C), which can be abolished using a TLR4 antagonist. Despite these findings, CAPW-1 did not alleviate the symptoms of lymphedema or restore lymphatic drainage in VEGFR3flox/flox/Prox1-CreERT2 mice. In summary, CAPW-1 alleviates secondary lymphedema by promoting lymphangiogenesis and lymphatic vessel remodeling through the activation of the TLR4/NF-κB/VEGF-C signaling pathway, indicating its potential as a therapeutic lymphangiogenesis agent for patients with secondary lymphedema.
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Galactanos , Linfangiogênese , Vasos Linfáticos , Linfedema , Receptor 4 Toll-Like , Animais , Linfangiogênese/efeitos dos fármacos , Camundongos , Linfedema/tratamento farmacológico , Linfedema/metabolismo , Linfedema/etiologia , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/metabolismo , Galactanos/farmacologia , Galactanos/química , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , NF-kappa B/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , MasculinoRESUMO
Cells expressing features of senescence, including upregulation of p21 and p16, appear transiently following tissue injury, yet the properties of these cells or how they contrast with age-induced senescent cells remains unclear. Here, we used skeletal injury as a model and identified the rapid appearance following fracture of p21+ cells expressing senescence markers, mainly as osteochondroprogenitors (OCHs) and neutrophils. Targeted genetic clearance of p21+ cells suppressed senescence-associated signatures within the fracture callus and accelerated fracture healing. By contrast, p21+ cell clearance did not alter bone loss due to aging; conversely, p16+ cell clearance, known to alleviate skeletal aging, did not affect fracture healing. Following fracture, p21+ neutrophils were enriched in signaling pathways known to induce paracrine stromal senescence, while p21+ OCHs were highly enriched in senescence-associated secretory phenotype factors known to impair bone formation. Further analysis revealed an injury-specific stem cell-like OCH subset that was p21+ and highly inflammatory, with a similar inflammatory mesenchymal population (fibro-adipogenic progenitors) evident following muscle injury. Thus, intercommunicating senescent-like neutrophils and mesenchymal progenitor cells were key regulators of tissue repair in bone and potentially across tissues. Moreover, our findings established contextual roles of p21+ versus p16+ senescent/senescent-like cells that may be leveraged for therapeutic opportunities.
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Senescência Celular , Inibidor de Quinase Dependente de Ciclina p21 , Consolidação da Fratura , Neutrófilos , Animais , Masculino , Camundongos , Biomarcadores/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Células-Tronco Mesenquimais/metabolismo , Neutrófilos/metabolismo , Neutrófilos/patologia , FemininoRESUMO
Cells expressing features of senescence, including upregulation of p21 and p16, appear transiently following tissue injury, yet the properties of these cells or how they contrast with age-induced senescent cells remains unclear. Here, we used skeletal injury as a model and identified the rapid appearance following fracture of p21+ cells expressing senescence markers, mainly as osteochondroprogenitors (OCHs) and neutrophils. Targeted genetic clearance of p21+ cells suppressed senescence-associated signatures within the fracture callus and accelerated fracture healing. By contrast, p21+ cell clearance did not alter bone loss due to aging; conversely, p16+ cell clearance, known to alleviate skeletal aging, did not affect fracture healing. Following fracture, p21+ neutrophils were enriched in signaling pathways known to induce paracrine stromal senescence, while p21+ OCHs were highly enriched in senescence-associated secretory phenotype factors known to impair bone formation. Further analysis revealed an injury-specific stem cell-like OCH subset that was p21+ and highly inflammatory, with a similar inflammatory mesenchymal population (fibro-adipogenic progenitors) evident following muscle injury. Thus, intercommunicating senescent-like neutrophils and mesenchymal progenitor cells are key regulators of tissue repair in bone and potentially across tissues. Moreover, our findings establish contextual roles of p21+ vs p16+ senescent/senescent-like cells that may be leveraged for therapeutic opportunities.
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Preclinical evidence demonstrates that senescent cells accumulate with aging and that senolytics delay multiple age-related morbidities, including bone loss. Thus, we conducted a phase 2 randomized controlled trial of intermittent administration of the senolytic combination dasatinib plus quercetin (D + Q) in postmenopausal women (n = 60 participants). The primary endpoint, percentage changes at 20 weeks in the bone resorption marker C-terminal telopeptide of type 1 collagen (CTx), did not differ between groups (median (interquartile range), D + Q -4.1% (-13.2, 2.6), control -7.7% (-20.1, 14.3); P = 0.611). The secondary endpoint, percentage changes in the bone formation marker procollagen type 1 N-terminal propeptide (P1NP), increased significantly (relative to control) in the D + Q group at both 2 weeks (+16%, P = 0.020) and 4 weeks (+16%, P = 0.024), but was not different from control at 20 weeks (-9%, P = 0.149). No serious adverse events were observed. In exploratory analyses, the skeletal response to D + Q was driven principally by women with a high senescent cell burden (highest tertile for T cell p16 (also known as CDKN2A) mRNA levels) in which D + Q concomitantly increased P1NP (+34%, P = 0.035) and reduced CTx (-11%, P = 0.049) at 2 weeks, and increased radius bone mineral density (+2.7%, P = 0.004) at 20 weeks. Thus, intermittent D + Q treatment did not reduce bone resorption in the overall group of postmenopausal women. However, our exploratory analyses indicate that further studies are needed testing the hypothesis that the underlying senescent cell burden may dictate the clinical response to senolytics. ClinicalTrials.gov identifier: NCT04313634 .
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Osteoclast-mediated bone resorption precedes osteoblast-mediated bone formation through early adulthood, but formation fails to keep pace with resorption during aging. We previously identified several factors produced by osteoclasts that promote bone formation. In this study, we determined if osteoclast-produced factors contribute to the impaired bone formation with aging. We previously found that mice between the ages of 18 and 22 months develop age-related bone loss. Bone marrow-derived pre-osteoclasts were isolated from 6-week, 12-month, and 18- to 24-month-old mice and differentiated into osteoclasts in vitro. Conditioned media were collected and compared for osteoblast mineralization support. Conditioned medium from osteoclasts from all ages was able to support mineralization of bone marrow stromal cells. Concentrating the conditioned medium from 6-week-old and 12-month-old mouse marrow cells-derived osteoclasts enhanced mineralization support whereas concentrated conditioned medium from 18- to 24-month-old mouse marrow-derived osteoclasts repressed mineralization compared to base medium. This observation suggests that an inhibitor of mineralization was secreted by aged murine osteoclasts. Gene and protein analysis revealed that the Wnt antagonist sclerostin was significantly elevated in the conditioned media from 24-month-old mouse cells compared to 6-week-old mouse cells. Antibodies directed to sclerostin neutralized the influences of the aged mouse cell concentrated conditioned media on mineralization. Sclerostin is primarily produced by osteocytes in young animals. This study demonstrates that osteoclasts from aged mice also produce sclerostin in quantities that may contribute to the age-related impairment in bone formation.
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Envelhecimento/metabolismo , Calcificação Fisiológica/fisiologia , Regulação da Expressão Gênica/fisiologia , Glicoproteínas/biossíntese , Osteoclastos/metabolismo , Osteogênese/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Células Cultivadas , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos Endogâmicos BALB C , Osteoclastos/citologiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Ligusticum striatum DC., also known as Ligusticum chuanxiong Hort. (LCH), is widely used in China for its excellent effect in ischaemic stroke (IS) patients, and borneol (BO) has been confirmed to maintain the bloodâbrain barrier (BBB) after stroke. They are often used as a combination in the prescriptions of IS patients. Although the advantage of their combined treatment in improving brain ischaemia has been verified, their synergistic mechanism on BBB maintenance is still unclear. AIM OF THE STUDY: This study was designed to evaluate the synergistic effect of maintaining the BBB between LCH and BO against IS and to further explore the potential mechanism. MATERIALS AND METHODS: After primary mouse brain microvascular endothelial cells (BMECs) were extracted and identified, the duration of oxygen-glucose deprivation (OGD) and the doses of LCH and BO were optimized. Then, the cells were divided into five groups: control, model, LCH, BO, and LCH + BO. Cell viability, injury degree, proliferation and migration were detected by CCK-8, LDH, EdU and wound-healing assays, respectively. Hoechst 33342 staining was adopted to detect the apoptosis rate, and western blotting was employed to observe the expressions of Bax, Bcl-2, caspase-3 and cleaved caspase-3. The TEER value and NaF permeability were measured to assess tight junction (TJ) function, while ZO-1, occludin and claudin-5 were also probed by western blotting. Moreover, the HIF-1α/VEGF pathway was observed to explore the underlying mechanism of BBB maintenance. In vivo, global cerebral ischaemia/reperfusion (GCIR) surgery was performed to establish an IS model. After treatment with LCH (200 mg/kg) and/or BO (160 mg/kg), histopathological structure and BMECs repair were observed by HE staining and immunohistochemistry of vWF. Meanwhile, TJ-associated proteins in vivo were also detected by western blotting. RESULTS: Basically, LCH and BO had different emphases. LCH significantly attenuated the vacuolar structure, nuclear pyknosis and neuronal loss of GCIR mice, while BO focused on promoting BMECs proliferation and angiogenesis and inhibiting the degradation of TJ-associated proteins in vivo after IS. Interestingly, their combination further enhanced these effects. OGD injury markedly reduced the viability, proliferation and migration of primary BMECs; decreased the ratio of Bcl-2/Bax, TEER value, and the expressions of ZO-1, occludin and claudin-5; induced LDH release and apoptosis; and increased the cleaved caspase-3/caspase-3 ratio and NaF permeability. Meanwhile, BO might be the main contributor to the combinative treatment in ameliorating OGD-induced damage of BMECs and degradation of TJ-related proteins, and the potential mechanism might be involved in upregulating the HIF-1α/VEGF signalling pathway. Although LCH showed no obvious improvement, it could enhance the therapeutic effect of BO. Interestingly, their combination even produced some new improvements, including the reduction of cleaved caspase-3 and increase in TEER value, none of which were exhibited in their monotherapies. CONCLUSIONS: LCH and BO exhibited complementary therapeutic features in alleviating cerebral ischaemic injury by inhibiting BMECs apoptosis, maintaining the BBB and attenuating the loss of neurons. LCH preferred to protect ischaemic neurons, while BO played a key role in protecting BMECs, maintaining the BBB and TJs by activating the HIF-1α/VEGF signalling pathway.
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Isquemia Encefálica , Ligusticum , Acidente Vascular Cerebral , Animais , Camundongos , Proteína X Associada a bcl-2/metabolismo , Barreira Hematoencefálica , Isquemia Encefálica/metabolismo , Caspase 3/metabolismo , Claudina-5/metabolismo , Células Endoteliais , Glucose/metabolismo , Ocludina/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: The aim of the study is to systematically review the effects of leg-driven treadmill-based exoskeleton robot training on balance and walking ability in poststroke patients. DESIGN: The PubMed, Cochrane Library, Embase, Web of Science, Medline, CNKI, VIP, and Wanfang databases were searched from inception to August 2021. The literature quality was evaluated using Cochrane Handbook. Primary outcomes include the Functional Ambulation Category Scale and Berg Balance Scale, and secondary outcomes include the 10 meter walk test, 6 minute walk test, and gait assessment cadence were analyzed. RESULTS: Seventeen randomized controlled trials were included in the systematic review, 15 studies in meta-analysis. Primary outcomes showed no significant difference in the Functional Ambulation Category Scale score; subgroup with the exoskeleton robot + conventional therapy of the Berg Balance Scale score was significantly increased; secondary outcomes showed no significance in 6 minute walk test or 10 meter walk test. The cadence score increased for the subgroup with an onset of more than 6 mos in the treatment group. The control group performed better than the subgroup with an onset of less than 6 mos. CONCLUSIONS: Leg-driven treadmill-based exoskeleton robot training can improve balance function in poststroke patients and is beneficial for patients with an onset of greater than 6 mos. However, there is no evidence to support the efficacy of walking ability.
Assuntos
Exoesqueleto Energizado , Robótica , Reabilitação do Acidente Vascular Cerebral , Humanos , Perna (Membro) , Caminhada , Marcha , Terapia por ExercícioRESUMO
BACKGROUND: Breast cancer is one of the most common cancers in women, affecting more than 2 million women worldwide annually. However, effective treatments for breast cancer are limited. Nobiletin is a flavonoid present in the dried mature pericarp of mandarin orange (Citrus reticulata Blanco), which is used to prepare Citri Renetulatae Pericarpium and can inhibit tumour growth and progression according to modern pharmacological studies. However, whether nobiletin exhibits an antimetastatic role in breast cancer and its potential mechanism need to be further investigated. PURPOSE: This study aims to evaluate the inhibitory effect of nobiletin on breast cancer and to elucidate potential mechanisms against invasion and migration. METHODS: Cell viability was determined by cell counting kit-8 and colony formation assays. Wound healing and Boyden chamber assays detected cancer cell migration and invasion capabilities. Immunoblotting and qPCR were applied to determine the protein and mRNA expression levels of extracellular signal-regulated kinases (ERK) and the c-Jun N-terminal kinase (JNK) signalling pathways. Molecular docking was used to assess the degree of nobiletin binding to phosphatidylinositol 3-kinase (PI3K). Xenografts and liver metastases were constructed in BALB/c nude mice to evaluate the anticancer effect of nobiletin in vivo. H&E staining and immunohistochemistry were used to detect proliferation and the expression of related proteins. RESULTS: Nobiletin induced cell death in a concentration- and time-dependent manner and possessed anti-invasion and anti-migration effects on MCF-7 and T47D cells by suppressing the interleukin-6-induced ERK and JNK signalling pathways. In addition, nobiletin docked with the binding site of PI3K, and the binding score was -8.0 kcal/mol. Furthermore, the inhibition of breast cancer growth and metastasis by nobiletin was demonstrated by constructing xenografts and liver metastases in vivo. CONCLUSION: Nobiletin inhibited liver metastasis of breast cancer by downregulating the ERK-STAT and JNK-c-JUN pathways, and its safety and efficacy were verified, indicating the potential of nobiletin as an anticancer agent.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular , Neoplasias Hepáticas , Animais , Feminino , Humanos , Camundongos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Interleucina-6/farmacologia , Camundongos Nus , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/metabolismoRESUMO
OBJECTIVE: To examine and quantify liver and kidney lesions and their response to anti-tumor necrosis factor (TNF) therapy in a TNF-Tg mouse model of rheumatoid arthritis (RA). METHODS: Female TNF-Tg (Tg3647) mice were used as the animal model for chronic RA. Ultrasound, immunofluorescence, histological staining, serology tests, and real-time RT-PCR were used to examine the pathological changes in the liver and kidney. RESULTS: TNF-Tg mice showed a significant decrease in the body weight and a dramatic increase in the volumes of the gallbladder, knee cavity, and popliteal lymph nodes. The liver and kidneys of TNF-Tg mice showed increased chronic inflammation and accumulation of immune cells and fibrosis, compared to wild-type (WT) mice. Moreover, upregulation of inflammatory factors and impaired normal function were observed in the liver and kidneys of TNF-Tg mice. Inflammatory infiltration and fibrosis of the liver and kidneys of female TNF-Tg mice were improved after anti-TNF treatment, and better treatment effects were achieved at 4.5-month-old mice when they were received 8 weeks of intervention. CONCLUSIONS: We found that TNF drives the development of liver and kidney pathology in female TNF-Tg mice and that there are limitations to the loss of utility of anti-TNF for the prolonged treatment of RA-associated hepatic and renal injury. This study provides a reliable and clinically relevant animal model for further studies exploring the molecular mechanisms and drug discovery for hepatorenal pathologies in RA.