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1.
J Am Chem Soc ; 146(19): 13093-13104, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690763

RESUMEN

The cluster-based body-centered-cubic superlattice (cBCC SL) represents one of the most complicated structures among reported nanocrystal assemblies, comprised of 72 truncated tetrahedral quantum dots per unit cell. Our previous report revealed that truncated tetrahedral quantum dots within cBCC SLs possessed highly controlled translational and orientational order owing to an unusual energetic landscape based on the balancing of entropic and enthalpic contributions during the assembly process. However, the cBCC SL's structural transformability and mechanical properties, uniquely originating from such complicated nanostructures, have yet to be investigated. Herein, we report that cBCC SLs can undergo dynamic transformation to face-centered-cubic SLs in response to post-assembly molecular exposure. We monitored the dynamic transformation process using in situ synchrotron-based small-angle X-ray scattering, revealing a dynamic transformation involving multiple steps underpinned by interactions between incoming molecules and TTQDs' surface ligands. Furthermore, our mechanistic study demonstrated that the precise configuration of TTQDs' ligand molecules in cBCC SLs was key to their high structural transformability and unique jelly-like soft mechanical properties. While ligand molecular configurations in nanocrystal SLs are often considered minor features, our findings emphasize their significance in controlling weak van der Waals interactions between nanocrystals within assembled SLs, leading to previously unremarked superstructural transformability and unique mechanical properties. Our findings promote a facile route toward further creation of soft materials, nanorobotics, and out-of-equilibrium assemblies based on nanocrystal building blocks.

2.
J Clin Med ; 12(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36902541

RESUMEN

This study investigated the therapeutic effects of transplanting human mesenchymal stem cells (hMSCs) into wild-type mice that were intraperitoneally administered cytosine arabinoside (Ara-C) to develop cerebellar ataxia (CA) during the first three postnatal days. hMSCs were intrathecally injected into 10-week-old mice once or thrice at 4-week intervals. Compared to the nontreated mice, the hMSC-treated mice showed improved motor and balance coordination, as measured using the rotarod, open-field, and ataxic scoring assessments, and increased protein levels in Purkinje and cerebellar granule cells, as measured using calbindin and NeuN protein markers. Multiple hMSC injections preserved Ara-C-induced cerebellar neuronal loss and improved cerebellar weight. Furthermore, the hMSC implantation significantly elevated the levels of neurotrophic factors, including brain-derived and glial cell line-derived neurotrophic factors, and suppressed TNF-α-, IL-1ß-, and iNOS-mediated proinflammatory responses. Collectively, our results demonstrate that hMSCs exhibit therapeutic potential for Ara-C-induced CA by protecting neurons through the stimulation of neurotrophic factors and inhibition of cerebellar inflammatory responses, which can improve motor behavior and alleviate ataxia-related neuropathology. In summary, this study suggests that hMSC administration, particularly multiple treatments, can effectively treat ataxia-related symptoms with cerebellar toxicity.

3.
ACS Nano ; 16(9): 15053-15062, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36048768

RESUMEN

Advances in the synthesis and self-assembly of nanocrystals have enabled researchers to create a plethora of different nanoparticle superlattices. But while many superlattices with complex types of translational order have been realized, rotational order of nanoparticle building blocks within the lattice is more difficult to achieve. Self-assembled superstructures with atomically coherent nanocrystal lattices, which are desirable due to their exceptional electronic and optical properties, have been fabricated only for a few selected systems. Here, we combine experiments with molecular dynamics (MD) simulations to study the self-assembly of heterostructural nanocrystals (HNCs), consisting of a near-spherical quantum dot (QD) host decorated with a small number of epitaxially grown gold nanocrystal (Au NC) "patches". Self-assembly of these HNCs results in face-centered-cubic (fcc) superlattices with well-defined orientational relationships between the atomic lattices of both QD hosts and Au patches. MD simulations indicate that the observed dual atomic coherence is linked to the number, size, and relative positions of gold patches. This study provides a strategy for the design and fabrication of NC superlattices with large structural complexity and delicate orientational order.

4.
Trials ; 23(1): 415, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585556

RESUMEN

BACKGROUND: A single cycle (two repeated treatments) with intrathecal autologous bone marrow-derived mesenchymal stem cells (BM-MSCs, 26-day interval) showed safety and provided therapeutic benefit lasting 6 months in patients with ALS but did not demonstrate long-term efficacy. This phase III clinical trial (ALSUMMIT) protocol was developed to evaluate the long-term efficacy and safety of the combined protocol of single-cycle intrathecal therapy and three additional booster injections of BM-MSC (Lenzumestrocel) treatment in patients with ALS. METHODS: ALSUMMIT is a multicentre, randomized, double-blind, parallel-group, sham procedure-controlled, phase III trial for ALS. The 115 subjects will be randomized (1:2:2) into three groups: (1) study Group 1 (single-cycle, two repeated injections with 26-day interval), (2) study Group 2 (single-cycle + three additional booster injections at 4, 7, and 10 months), and (3) the control group. Participants who have an intermediate rate of disease progression will be included in this trial to reduce clinical heterogeneity. The primary endpoint will be evaluated by combined assessment of function and survival (CAFS), also known as joint rank scores (JRS), at 6 months (study Group 1 vs. control) and 12 months (study Group 2 vs. control) after the first Lenzumestrocel or placebo administration. Safety assessment will be performed throughout the study period. Additionally, after the 56-week main study, a long-term follow-up observational study will be conducted to evaluate the long-term efficacy and safety up to 36 months. DISCUSSION: Lenzumestrocel is the orphan cell therapy product for ALS conditionally approved by the South Korea Ministry of Food and Drug Safety (MFDS). This ALSUMMIT protocol was developed for the adoption of enrichment enrolment, add-on design, and consideration of ethical issues for the placebo group. TRIAL REGISTRATION: ClinicalTrials.gov NCT04745299 . Registered on Feb 9, 2021. Clinical Research Information Service (CRIS) KCT0005954 . Registered on Mar 4, 2021.


Asunto(s)
Esclerosis Amiotrófica Lateral , Células Madre Mesenquimatosas , Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Tratamiento Basado en Trasplante de Células y Tejidos , Ensayos Clínicos Fase III como Asunto , Progresión de la Enfermedad , Método Doble Ciego , Humanos , Estudios Multicéntricos como Asunto , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
5.
Medicina (Kaunas) ; 57(4)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915966

RESUMEN

To date, there is no curable treatment option for non-hereditary degenerative cerebellar ataxia. Here we report the case of a patient with sporadic adult-onset ataxia (SAOA) who underwent allogeneic bone marrow-derived mesenchymal stem cell (MSC) therapy via the intrathecal route. A 60-year-old male patient visited our clinic complaining of progressive gait disturbance that commenced two years ago. Upon neurologic examination, the patient exhibited limb dysmetria and gait ataxia. Brain magnetic resonance imaging (MRI) revealed cerebellar atrophy whereas the autonomic function test was normal. The patient was diagnosed with SAOA. The medications that were initially prescribed had no significant effects on the course of this disease and the symptoms deteriorated progressively. At the age of 64, the patient was treated with allogeneic bone marrow-derived MSC therapy. The subsequent K-SARA (Korean version of the Scale for the Assessment and Rating of Ataxia) scores demonstrated a distinct improvement up until 10 months post-administration. No adverse events were reported. The improved post-treatment K-SARA scores may suggest that the MSC therapy can have a neuroprotective effect and that stem cell therapy may serve as a potential therapeutic option for degenerative cerebellar ataxia.


Asunto(s)
Ataxia Cerebelosa , Trasplante de Células Madre Hematopoyéticas , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Adulto , Médula Ósea , Ataxia Cerebelosa/terapia , Humanos , Masculino , Persona de Mediana Edad
6.
Polymers (Basel) ; 12(11)2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33198091

RESUMEN

Herein, we report a drug eluting scaffold composed of a composite nanofibers of poly(ε-caprolactone) (PCL) and poly(glycerol sebacate) (PGS) loaded with Hydroxyapatite nanoparticles (HANPs) and simvastatin (SIM) mimicking the bone extracellular matrix (ECM) to improve bone cell proliferation and regeneration process. Indeed, the addition of PGS results in a slight increase in the average fiber diameter compared to PCL. However, the presence of HANPs in the composite nanofibers induced a greater fiber diameter distribution, without significantly changing the average fiber diameter. The in vitro drug release result revealed that the sustained release of SIM from the composite nanofiber obeying the Korsemeyer-Peppas and Kpocha models revealing a non-Fickian diffusion mechanism and the release mechanism follows diffusion rather than polymer erosion. Biomineralization assessment of the nanofibers was carried out in simulated body fluid (SBF). SEM and EDS analysis confirmed nucleation of the hydroxyapatite layer on the surface of the composite nanofibers mimicking the natural apatite layer. Moreover, in vitro studies revealed that the PCL-PGS-HA displayed better cell proliferation and adhesion compared to the control sample, hence improving the regeneration process. This suggests that the fabricated PCL-PGS-HA could be a promising future scaffold for control drug delivery and bone tissue regeneration application.

7.
J Clin Med ; 9(11)2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33202913

RESUMEN

Cerebellar ataxias (CAs) are neurological diseases characterized by loss of muscle coordination that is a result of damage and inflammation to the cerebellum. Despite considerable efforts in basic and clinical research, most CAs are currently incurable. In this study, we evaluated the therapeutic potential of human mesenchymal stem cells (hMSCs) against CAs associated with neuroinflammation. We observed that hMSC treatment significantly inhibited the symptoms of ataxia in lipopolysaccharide (LPS)-induced inflammatory CA (ICA) mice, which were recently reported as a potential animal model of ICA, through the anti-inflammatory effect of hMSC-derived TNFα-stimulated gene-6 (TSG-6), the protection of Purkinje cells by inhibition of apoptosis, and the modulatory effect for microglial M2 polarization. Thus, our results suggest that hMSC treatment may be an effective therapeutic approach for preventing or improving ataxia symptoms.

8.
Theranostics ; 10(22): 10186-10199, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32929342

RESUMEN

Rationale: Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease characterized by autoantibody production by hyper-activated B cells. Although mesenchymal stem cells (MSCs) ameliorate lupus symptoms by inhibiting T cells, whether they inhibit B cells has been controversial. Here we address this issue and reveal how to prime MSCs to inhibit B cells and improve the efficacy of MSCs in SLE. Methods: We examined the effect of MSCs on purified B cells in vitro and the therapeutic efficacy of MSCs in lupus-prone MRL.Faslpr mice. We screened chemicals for their ability to activate MSCs to inhibit B cells. Results: Mouse bone marrow-derived MSCs inhibited mouse B cells in a CXCL12-dependent manner, whereas human bone marrow-derived MSCs (hMSCs) did not inhibit human B (hB) cells. We used a chemical approach to overcome this hurdle and found that phorbol myristate acetate (PMA), phorbol 12,13-dibutyrate, and ingenol-3-angelate rendered hMSCs capable of inhibiting IgM production by hB cells. As to the mechanism, PMA-primed hMSCs attracted hB cells in a CXCL10-dependent manner and induced hB cell apoptosis in a PD-L1-dependent manner. Finally, we showed that PMA-primed hMSCs were better than naïve hMSCs at ameliorating SLE progression in MRL.Faslpr mice. Conclusion: Taken together, our data demonstrate that phorbol esters might be good tool compounds to activate MSCs to inhibit B cells and suggest that our chemical approach might allow for improvements in the therapeutic efficacy of hMSCs in SLE.


Asunto(s)
Linfocitos B/efectos de los fármacos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Células Madre Mesenquimatosas/efectos de los fármacos , Ésteres del Forbol/farmacología , Animales , Apoptosis/efectos de los fármacos , Células Cultivadas , Femenino , Humanos , Masculino , Trasplante de Células Madre Mesenquimatosas , Ratones , Ratones Endogámicos C3H , Linfocitos T/efectos de los fármacos
9.
Sci Rep ; 10(1): 13337, 2020 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-32770064

RESUMEN

Most cerebellar ataxias (CAs) are incurable neurological disorders, resulting in a lack of voluntary control by inflamed or damaged cerebellum. Although CA can be either directly or indirectly related to cerebellar inflammation, there is no suitable animal model of CA with neuroinflammation. In this study, we evaluated the utility of an intracerebellar injection of lipopolysaccharide (LPS) to generate an animal model of inflammatory CA. We observed that LPS administration induced the expression of pro-inflammatory molecules following activation of glial cells. In addition, the administration of LPS resulted in apoptotic Purkinje cell death and induced abnormal locomotor activities, such as impaired motor coordination and abnormal hindlimb clasping posture. Our results suggest that intracerebellar LPS administration in experimental animals may be useful for studying the inflammatory component of CA.


Asunto(s)
Ataxia Cerebelosa/inducido químicamente , Inflamación/inducido químicamente , Lipopolisacáridos/administración & dosificación , Animales , Células Cultivadas , Cerebelo/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Neuroglía/efectos de los fármacos , Células de Purkinje/efectos de los fármacos
10.
Stem Cells Int ; 2020: 5617192, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32215018

RESUMEN

Systemic lupus erythematosus (SLE) is an autoimmune disease, which is characterized by hyperactivation of T and B cells. Human mesenchymal stem cells (hMSCs) ameliorate the progression of SLE in preclinical studies using lupus-prone MRL.Fas lpr mice. However, whether hMSCs inhibit the functions of xenogeneic mouse T and B cells is not clear. To address this issue, we examined the in vitro effects of hMSCs on T and B cells isolated from MRL.Fas lpr mice. Naïve hMSCs inhibited the functions of T cells but not B cells. hMSCs preconditioned with IFN-γ (i) inhibited the proliferation of and IgM production by B cells, (ii) attracted B cells for cell-cell interactions in a CXCL10-dependent manner, and (iii) inhibited B cells by producing indoleamine 2,3-dioxygenase. In summary, our data demonstrate that hMSCs exert therapeutic activity in mice in three steps: first, naïve hMSCs inhibit the functions of T cells, hMSCs are then activated by IFN-γ, and finally, they inhibit B cells.

11.
Cells ; 9(1)2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31952198

RESUMEN

Mesenchymal stem cell (MSC) therapy is a promising alternative approach for the treatment of neurodegenerative diseases, according to its neuroprotective and immunomodulatory potential. Despite numerous clinical trials involving autologous MSCs, their outcomes have often been unsuccessful. Several reports have indicated that MSCs from patients have low capacities in terms of the secretion of neurotrophic or anti-inflammatory factors, which might be associated with cell senescence or disease severity. Therefore, a new strategy to improve their capacities is required for optimal efficacy of autologous MSC therapy. In this study, we compared the secretory potential of MSCs among cerebellar ataxia patients (CA-MSCs) and healthy individuals (H-MSCs). Our results, including secretome analysis findings, revealed that CA-MSCs have lower capacities in terms of proliferation, oxidative stress response, motility, and immunomodulatory functions when compared with H-MSCs. The functional differences were validated in a scratch wound healing assay and neuron-glia co-cultures. In addition, the neuroprotective and immunoregulatory protein follistatin-like 1 (FSTL1) was identified as one of the downregulated proteins in the CA-MSC secretome, with suppressive effects on proinflammatory microglial activation. Our study findings suggest that targeting aspects of the downregulated anti-inflammatory secretome, such as FSTL1, might improve the efficacy of autologous MSC therapy for CA.


Asunto(s)
Ataxia Cerebelosa/metabolismo , Regulación hacia Abajo , Proteínas Relacionadas con la Folistatina/metabolismo , Células Madre Mesenquimatosas/metabolismo , Animales , Proliferación Celular , Células Cultivadas , Ataxia Cerebelosa/patología , Humanos , Células Madre Mesenquimatosas/patología , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo
12.
Immune Netw ; 19(5): e36, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31720047

RESUMEN

Mesenchymal stem cells (MSCs) ameliorate the renal injury in Adriamycin (ADR)-induced nephropathy, but the mechanisms underlying their efficacy remain incompletely understood. In this study, we demonstrated that MSCs increased the survival, recovered body weight loss, and decreased proteinuria and serum creatinine levels in ADR-treated mice. MSCs also prevented podocyte damage and renal fibrosis by decreasing the expression of fibronectin, collagen 1α1, and α-smooth muscle actin. From a mechanistic perspective, MSCs inhibited renal inflammation by lowering the expression of CCL4, CCL7, CCL19, IFN-α/ß, TGF-ß, TNF-α, and chitinase 3-like 1. In summary, our data demonstrate that MSCs improve renal functions by inhibiting renal inflammation in ADR-induced nephropathy.

13.
Proc Math Phys Eng Sci ; 475(2221): 20180671, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30760967

RESUMEN

As a sequel of part I (Kothari et al. 2018 Proc. R. Soc. A 474, 20180054), we present a general thermodynamic framework of flexoelectric constitutive laws for multi-layered graphene (MLG), and apply these laws to explain the role of crinkles in peculiar molecular adsorption characteristics of highly oriented pyrolytic graphite (HOPG) surfaces. The thermodynamically consistent constitutive laws lead to a non-local interaction model of polarization induced by electromechanical deformation with flexoelectricity-dielectricity coupling. The non-local model predicts curvature and polarization localization along crinkle valleys and ridges very close to those calculated by density functional theory (DFT). Our analysis reveals that the non-local model can be reduced to a simplified uc-local or e-local model (Kothari et al. 2018 Proc. R. Soc. A 474, 20180054) only when the curvature distribution is uniform or highly localized. For the non-local model, we calibrated and formulated the layer-number-dependent dielectric and intrinsic flexoelectric coefficients of MLGs. In addition, we also obtained layer-number dependent flexoelectric coefficients for uc-local and e-local models. Our DFT analysis shows that polarization-induced adsorption of neutral molecules at crinkle ridges depends on the molecular weight of the molecule. Furthermore, our detailed study of polarization localization in graphene crinkles enables us to understand previously unexplained self-organized adsorption of C60 buckyballs in a linear array on an HOPG surface.

14.
Stem Cells Int ; 2018: 4273107, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30057623

RESUMEN

The combination of immunosuppressants and mesenchymal stem cells (MSCs) is a promising therapeutic strategy for systemic lupus erythematosus, since this approach reduces doses of immunosuppressants while maintaining the same therapeutic outcome. However, it is unavoidable for MSCs to be exposed to immunosuppressants. Here, we examined the combination effect of prednisone (PD) or mycophenolate mofetil (MMF) and MSCs. We showed that PD or MMF in combination with MSCs showed better therapeutic effect than single therapy in lupus-prone MRL.Faslpr mice, as assessed by using the following readouts: prolongation of survival, decrease in anti-dsDNA and total IgG levels in serum, decrease in cytokine gene expression in spleen cells, and decrease in inflammatory cell infiltration into the kidney. In vitro, immunosuppressants and MSCs inhibited T cell proliferation in a synergistic manner. However, immunosuppressants did not affect MSC viability and functions such as TGF-ß1 and PGE2 production, migration, and immunosuppressive capacity. In summary, our study demonstrates that a combination of immunosuppressants and MSCs is a good strategy to reduce the side effects of PD and MMF without the loss of therapeutic outcome.

15.
Proc Math Phys Eng Sci ; 474(2214): 20180054, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29977131

RESUMEN

Here, we report the discovery of a new, curvature-localizing, subcritical buckling mode that produces shallow-kink corrugation in multi-layer graphene. Our density functional theory (DFT) analysis reveals the mode configuration-an approximately 2 nm wide boundary layer of highly localized curvature that connects two regions of uniformly but oppositely sheared stacks of flat atomic sheets. The kink angle between the two regions is limited to a few degrees, ensuring elastic deformation. By contrast, a purely mechanical model of sandwich structures shows progressive supercritical curvature localization spread over a 50-100 nm wide boundary layer. Our effective-locality model of electromechanics reveals that coupling between atomic-layer curvature and electric-charge polarization, i.e. quantum flexoelectricity, leads to emergence of a boundary layer in which curvature is focused primarily within a 0.86 nm fixed band width. Both DFT and the model analyses show focused distributions of curvature and polarization exhibiting oscillating decay within the approximately 2 nm wide boundary layer. The results show that dipole-dipole interaction lowers the potential energy with such a distribution. Furthermore, this model predicts peak-polarization density approximately 0.12 e- nm-1 for 3° tilt angle. This high polarization concentration can be controlled by macroscopic deformation and is expected to be useful in studies of selective graphene-surface functionalization for various applications.

16.
Dalton Trans ; 47(13): 4455-4466, 2018 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-29504611

RESUMEN

In this study, a novel composite of Cu-Al layered double hydroxide (LDH) nanosheets and g-C3N4-covered Ni-foam was fabricated via a simple and facile two-step process. First, g-C3N4 sheets were deposited on Ni-foam by via electrodeposition method on a three-electrode system (Ni-foam@g-C3N4) and then, Cu-Al LDH nanosheets were grown on the Ni-foam via in situ redox reaction using a hydrothermal process (Ni-foam@Cu-Al LDH/g-C3N4). The FE-SEM image confirmed that the Cu-Al LDH nanosheets arose vertically and were anchored on the surface of electrodeposited g-C3N4 sheets, thus generating unique 3D porous interconnected networks. The electrochemical capacitive performances of the as-prepared samples were evaluated by cyclic volatammetry (CV), galvanostatic charge/discharge tests, and electrochemical impedance spectra (EIS) Nyquist plots. The specific capacitances of the Ni-foam@Cu-Al LDH/g-C3N4 nanocomposite measured from the CV curve (770.98 F g-1 at 50 mV s-1) and the galvanostatic charge/discharge curve (831.871 at 0.4 A g-1) were significantly higher than the others. Moreover, the Ni-foam@Cu-Al LDH/g-C3N4 nanocomposite revealed a remarkable high-current capacitive behavior and the capacitance retention could be maintained at 92.71% even after 5000 cycles of CV. Thus, the obtained results demonstrated that the as-prepared nanocomposite has great potential to be used as a novel supercapacitor electrode.

17.
J Colloid Interface Sci ; 518: 234-241, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29462758

RESUMEN

Mesoporous architectures are remarkable electrode materials for energy storage system due to their large number of active sites and high surface area. Here we report, mesoporous MoS2 particles (pore diameter 34.04 nm) well attached to the surface of thin layered reduced graphene oxide (rGO) via an ultrasonic chemical method for supercapacitor applications. The rGO not only increases the conductivity of MoS2 but also provides a substrate for the attachment of MoS2 with low aggregation. The porous MoS2 provides a large surface area and sufficient way for the fast transport of electrolyte ions toward electrode materials. As a result, the synthesized MoS2/rGO composites exhibited excellent electrochemical performance with a specific capacitance 314.5 F/g in 2M KOH aqueous solution at a scan rate of 10 mV/s and excellent specific capacitance retention (80.02%) after 1000 cycles in a three electrode system for energy storage applications.

18.
Ann Dermatol ; 29(1): 6-12, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28223740

RESUMEN

BACKGROUND: Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier. OBJECTIVE: We examined whether kinetin induces skin barrier functions in vitro and in vivo. METHODS: To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers was assessed. Moreover, we examined the clinical efficacy of kinetin by evaluating skin moisture, transepidermal water loss (TEWL), and skin surface roughness in patients who used kinetin-containing cream. We performed quantitative real-time polymerase chain reaction to measure the expression of keratinocyte differentiation markers in HaCaT cells following treatment. A clinical trial was performed to assess skin moisture, TEWL, and evenness of skin texture in subjects who used kinetin-containing cream for 4 weeks. RESULTS: Kinetin increased involucrin, and keratin 1 mRNA in HaCaT cells. Moreover, use of a kinetin-containing cream improved skin moisture and TEWL while decreasing roughness of skin texture. CONCLUSION: Kinetin induced the expression of keratinocyte differentiation markers, suggesting that it may affect differentiation to improve skin moisture content, TEWL, and other signs of skin aging. Therefore, kinetin is a potential new component for use in cosmetics as an anti-aging agent that improves the barrier function of skin.

19.
Stem Cells Transl Med ; 5(11): 1538-1549, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27400795

RESUMEN

: The regulation of microglial cell phenotype is a potential therapeutic intervention in neurodegenerative disease. Previously, we reported that transforming growth factor-ß (TGF-ß) levels in mesenchymal stromal cells (MSCs) could be used as potential biological markers to predict the effectiveness of autologous MSC therapy in patients with amyotrophic lateral sclerosis. However, the underlying mechanism of TGF-ß in MSCs was not fully elucidated in determining the functional properties of microglia. In this study, we aimed to clarify the role of TGF-ß that is involved in MSC effectiveness, especially focusing on microglia functional properties that play a pivotal role in neuroinflammation. We found that MSC-conditioned media (MSC-CM) inhibited proinflammatory cytokine expression, restored alternative activated microglia phenotype markers (fractalkine receptor, mannose receptor, CD200 receptor), and enhanced phagocytosis in lipopolysaccharide (LPS)-stimulated microglia. In addition, TGF-ß in MSC-CM played a major role in these effects by inhibiting the nuclear factor-κB pathway and restoring the TGF-ß pathway in LPS-stimulated microglia. Recombinant TGF-ß also induced similar effects to MSC-CM in LPS-stimulated microglia. Therefore, we propose that MSCs can modulate the functional properties of microglia via TGF-ß secretion, switching them from a classically activated phenotype to an inflammation-resolving phenotype. The latter role may be associated with the inhibition of neuroinflammatory processes in neurodegenerative disorders. SIGNIFICANCE: The results of this study showed that microglia functional properties may be modulated depending on the composition and quantity of mesenchymal stromal cell (MSC)-secreting factors. Transforming growth factor (TGF)-ß is proposed as a modulator of microglia functional properties among MSC-secreting factors, and this study aligns with a previous clinical study by these same authors. TGF-ß releasing capacity could be an important factor enhancing the therapeutic efficacy of MSCs in clinical trials.

20.
Ann Dermatol ; 28(3): 327-34, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27274631

RESUMEN

BACKGROUND: Dihydrotestosterone (DHT) induces androgenic alopecia by shortening the hair follicle growth phase, resulting in hair loss. We previously demonstrated how changes in the microRNA (miRNA) expression profile influenced DHT-mediated cell death, cell cycle arrest, cell viability, the generation of reactive oxygen species (ROS), and senescence. Protective effects against DHT have not, however, been elucidated at the genome level. OBJECTIVE: We showed that epigallocatechin gallate (EGCG), a major component of green tea, protects DHT-induced cell death by regulating the cellular miRNA expression profile. METHODS: We used a miRNA microarray to identify miRNA expression levels in human dermal papilla cells (DPCs). We investigated whether the miRNA expression influenced the protective effects of EGCG against DHT-induced cell death, growth arrest, intracellular ROS levels, and senescence. RESULTS: EGCG protected against the effects of DHT by altering the miRNA expression profile in human DPCs. In addition, EGCG attenuated DHT-mediated cell death and growth arrest and decreased intracellular ROS levels and senescence. A bioinformatics analysis elucidated the relationship between the altered miRNA expression and EGCG-mediated protective effects against DHT. CONCLUSION: Overall, our results suggest that EGCG ameliorates the negative effects of DHT by altering the miRNA expression profile in human DPCs.

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