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1.
Int Orthop ; 48(1): 279-290, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37646823

RESUMEN

PURPOSE: Mesenchymal stem cells/medicinal signaling cells (MSCs) possess therapeutic potential and are used in regenerative orthopaedics. The infra-patellar fat pad (IFP) is partially resected during knee arthroscopy (KASC) and contains MSCs. Heat, irrigation, and mechanical stress during KASC may decrease MSC's therapeutic potential. This study assessed MSCs' regenerative potential after arthroscopic IFP harvest and potential effects of two blood products (BP) (platelet-rich plasma (PRP), hyperacute serum (HAS)) on MSCs' viability and chondrogenic differentiation capacity. METHODS: IFP was arthroscopically harvested, isolated, and counted (n = 5). Flow cytometry was used to assess cell viability via staining with annexin V/7-AAD and stemness markers via staining for CD90, CD73, and CD105. MSCs were incubated with blood products, and metabolic activity was determined via an XTT assay. Deposition of cartilage extracellular matrix was determined in histologic sections of chondrogenically differentiated 3D pellet cultures via staining with Alcian Blue. Expression of cartilage-specific genes (SOX9, MMP3/13, ACAN, COL1/2) was analyzed via quantitative PCR. RESULTS: MSC isolation from IFP yielded 2.66*106 ± 1.49*106 viable cells from 2.7 (0.748) g of tissue. MSC markers (CD 90/105/73) were successfully detected and annexin V staining showed 81.5% viable cells. XTT showed increased metabolic activity. Within the BP groups, this increase was significant (days 0-14, p < 0.05). PCR showed expression of cartilage-specific genes in each group. COL2 (p < 0.01) as well as ACAN (p < 0.001) expression levels were significantly higher in the HAS group. Histology showed successful differentiation. CONCLUSION: Arthroscopic harvest of IFP-MSCs yields sufficient cells with maintained regenerative potential and viability. Blood products further enhance MSCs' viability.


Asunto(s)
Tejido Adiposo , Células Madre Mesenquimatosas , Humanos , Anexina A5/metabolismo , Células Cultivadas , Diferenciación Celular , Suplementos Dietéticos , Condrogénesis
2.
Nutrients ; 14(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36235593

RESUMEN

Oxidative stress induces DNA damage which can be repaired by DNA repair proteins, such as Ku70/80. Excess reactive oxygen species (ROS) stimulate the activation of caspase-3, which degrades Ku 70/80. Cells with decreased Ku protein levels undergo apoptosis. Astaxanthin exerts antioxidant activity by inducing the expression of catalase, an antioxidant enzyme, in gastric epithelial cells. Therefore, astaxanthin may inhibit oxidative stress-induced DNA damage by preventing Ku protein degradation and thereby suppressing apoptosis. Ku proteins can be degraded via ubiquitination and neddylation which adds ubiquitin-like protein to substrate proteins. We aimed to determine whether oxidative stress decreases Ku70/80 expression through the ubiquitin-proteasome pathway to induce apoptosis and whether astaxanthin inhibits oxidative stress-induced changes in gastric epithelial AGS cells. We induced oxidative stress caused by the treatment of ß-D-glucose (G) and glucose oxidase (GO) in the cells. As a result, the G/GO treatment increased ROS levels, decreased nuclear Ku protein levels and Ku-DNA-binding activity, and induced the ubiquitination of Ku80. G/GO increased the DNA damage marker levels (γ-H2AX; DNA fragmentation) and apoptosis marker annexin V-positive cells and cell death. Astaxanthin inhibited G/GO-induced alterations, including Ku degradation in AGS cells. MLN4924, a neddylation inhibitor, and MG132, a proteasome inhibitor, suppressed G/GO-mediated DNA fragmentation and decreased cell viability. These results indicated that G/GO-induced oxidative stress causes Ku protein loss through the ubiquitin-proteasome pathway, resulting in DNA fragmentation and apoptotic cell death. Astaxanthin inhibited oxidative stress-mediated apoptosis via the reduction of ROS levels and inhibition of Ku protein degradation. In conclusion, dietary astaxanthin supplementation or astaxanthin-rich food consumption may be effective for preventing or delaying oxidative stress-mediated cell damage by suppressing Ku protein loss and apoptosis in gastric epithelial cells.


Asunto(s)
Antioxidantes , Complejo de la Endopetidasa Proteasomal , Anexina A5/metabolismo , Anexina A5/farmacología , Antioxidantes/metabolismo , Antioxidantes/farmacología , Apoptosis , Caspasa 3/metabolismo , Catalasa/metabolismo , ADN/metabolismo , Proteínas de Unión al ADN/genética , Células Epiteliales/metabolismo , Glucosa/metabolismo , Glucosa Oxidasa/metabolismo , Glucosa Oxidasa/farmacología , Autoantígeno Ku/metabolismo , Estrés Oxidativo , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Proteolisis , Especies Reactivas de Oxígeno/metabolismo , Ubiquitinas/metabolismo , Ubiquitinas/farmacología , Xantófilas
3.
J Ethnopharmacol ; 299: 115658, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36075273

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia argyi H. Lév. & Vaniot (Asteraceae), also called "Chinese mugwort", is frequently used as a herbal medicine in China, Japan, Korea, and eastern parts of Russia. It is known as "ai ye" in China and "Gaiyou" in Japan. In ancient China, the buds and leaves of A. argyi were commonly consumed before and after Tomb-sweeping Day. It is used to treat malaria, hepatitis, cancer, inflammatory diseases, asthma, irregular menstrual cycle, sinusitis, and pathologic conditions of the kidney and liver. Although A. argyi extract (AAE) has shown anti-tumor activity against various cancers, the therapeutic effect and molecular mechanism of AAE remains to be further studied in lung cancer. AIM OF THE STUDY: This study aimed to demonstrate the anti-tumor effect of AAE and its associated biological mechanisms in CL1-0 parent and gemcitabine-resistant (CL1-0-GR) lung cancer cells. EXPERIMENTAL PROCEDURE: Human lung cancer cells CL1-0 and CL1-0-GR cells were treated with AAE. Cell viability was assessed using the MTT, colony, and spheroid formation assays. Migration, invasion, and immunofluorescence staining were used to determine the extent of epithelial- mesenchymal transition (EMT). JC-1 and MitoSOX fluorescent assays were performed to investigate the effect of AAE on mitochondria. Apoptosis was detected using the TUNEL assay and flow cytometry with Annexin V staining. RESULT: We found that A. argyi significantly decreased cell viability and induced apoptosis, accompanied by mitochondrial membrane depolarization and increased ROS levels in both parent cells (CL1-0) and gemcitabine-resistant lung cancer cells (CL1-0-GR). AAE-induced apoptosis is regulated via the PI3K/AKT and MAPK signaling pathways. It also prevents CL1-0 and CL1-0-GR cancer cell invasion, migration, EMT, colony formation, and spheroid formation. In addition, AAE acts cooperative with commercial chemotherapy drugs to enhance tumor spheroid shrinkage. CONCLUSION: Our study provides the first evidence that A. argyi treatment suppresses both parent and gemcitabine-resistant lung cancer cells by inducing ROS, mitochondrial membrane depolarization, and apoptosis, and reducing EMT. Our finding provides insights into the anti-cancer activity of A. argyi and suggests that A. argyi may serve as a chemotherapy adjuvant that potentiates the efficacy of chemotherapeutic agents.


Asunto(s)
Apoptosis , Artemisia , Neoplasias Pulmonares , Anexina A5/metabolismo , Anexina A5/farmacología , Anexina A5/uso terapéutico , Apoptosis/efectos de los fármacos , Artemisia/química , Línea Celular Tumoral , Desoxicitidina/análogos & derivados , Resistencia a Antineoplásicos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Quinasas de Proteína Quinasa Activadas por Mitógenos/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Gemcitabina
4.
J Food Biochem ; 46(10): e14301, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35765891

RESUMEN

Vitiligo is a skin disease characterized by lack of functional melanocytes. Lycium barbarum polysaccharide (LBP) has been demonstrated to preserve keratinocytes and fibroblasts against oxidative stress. This study aimed to explore the efficacy and underlying mechanisms of LBP on autophagy in H2 O2 -damaged human melanocytes. Cellular viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and annexin V-fluorescein isothiocyanate/propidium iodide double staining. Reverse transcription-polymerase chain reaction, western blotting and electron microscopy were performed to detect autophagy. The protein expression level of Nrf2 and p62 were assessed by western blotting. Plasmid transfection and lentiviral infection were used to overexpress and silence Nrf2 in PIG1 cells. LBP promoted the proliferation and inhibited apoptosis of H2 O2 -damaged PIG1 cells. LBP increased the proliferation of H2 O2 -damaged PIG1 cells via induction of autophagy, and Nrf2 shRNA experiment confirmed that LBP activated the Nrf2/p62 signal pathway. These results suggest that LBP may be used for the treatment of vitiligo. PRACTICAL APPLICATIONS: Goji berry is the mature and dried fruit of Lycium barbarum L., which is a common food with a long history in China, as well as a Traditional Chinese Medicine. Our previous research found that LBP could activated the Nrf2/ARE pathway in an ultraviolet (UV)-induced photodamage model of keratinocytes, and increase the levels of phase II detoxification and antioxidant enzymes. We firstly confirmed the anti-vitiligo effects of L. barbarum polysaccharide (LBP) by inducing autophagy and promoted proliferation of human melanocytes, and LBP induced autophagy via activating the Nrf2/p62 signaling pathway in this study. These results proved that LBP can be an effective therapy for vitiligo treatment.


Asunto(s)
Antioxidantes , Factor 2 Relacionado con NF-E2 , Anexina A5/metabolismo , Anexina A5/farmacología , Antioxidantes/farmacología , Autofagia , Proliferación Celular , Medicamentos Herbarios Chinos , Fluoresceínas/farmacología , Humanos , Isotiocianatos/farmacología , Melanocitos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Polisacáridos/farmacología , Propidio/farmacología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Transducción de Señal
5.
Planta Med ; 88(13): 1132-1140, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34861701

RESUMEN

1,3,5-Tri-O-caffeoyl quinic acid is a caffeoylquinic acid derivative isolated from the roots of Arctium lappa L. Our previous studies have revealed that the ethyl acetate extract of the roots of A. lappa L. and the caffeoylquinic acids contained in it possess antioxidant properties, especially 1,3,5-tri-O-caffeoyl quinic acid. The present study aimed to investigate the protective effects of 1,3,5-tri-O-caffeoyl quinic acid against hydrogen peroxide-induced oxidative stress and explore the underlying mechanism. We found that 1,3,5-tri-O-caffeoyl quinic acid prevented the decline of cell viability and excessive release of lactate dehydrogenase induced by hydrogen peroxide. In addition, Hoechst 33 342 staining and Annexin V-PI double staining showed that 1,3,5-tri-O-caffeoyl quinic acid inhibited hydrogen peroxide-induced neuronal cell apoptosis. 1,3,5-Tri-O-caffeoyl quinic acid reduced the excessive production of intracellular reactive oxygen species, decreased the malondialdehyde content, and improved the activity of superoxide dismutase. Furthermore, 1,3,5-tri-O-caffeoyl quinic acid restored the loss of mitochondrial membrane potential in SH-SY5Y cells induced by hydrogen peroxide. 1,3,5-Tri-O-caffeoyl quinic acid downregulated the overexpression of proapoptotic proteins, including Bax, cytochrome c, cleaved caspase-9, and cleaved caspase-3 as well as promoted the expression of the antiapoptotic protein Bcl-2. Moreover, the phosphorylation of mitogen-activated protein kinases induced by hydrogen peroxide was inhibited by 1,3,5-tri-O-caffeoyl quinic acid. Pretreatment with 1,3,5-tri-O-caffeoyl quinic acid also promoted the activation of phosphorylated Akt. Taken together, these findings suggest that 1,3,5-tri-O-caffeoyl quinic acid exerts protective effects against hydrogen peroxide-induced neuronal apoptosis. In addition, inhibition of the mitogen-activated protein kinase signaling pathway and the activation of Akt are implicated in the antioxidant activity of 1,3,5-tri-O-caffeoyl quinic acid, giving new insight in searching for a compound with antioxidant activity for the treatment of oxidative stress-associated neurological diseases.


Asunto(s)
Peróxido de Hidrógeno , Neuroblastoma , Humanos , Ácido Quínico/farmacología , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Caspasa 9/farmacología , Fosforilación , Antioxidantes/farmacología , Antioxidantes/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Citocromos c/metabolismo , Citocromos c/farmacología , Anexina A5/metabolismo , Anexina A5/farmacología , Proteína X Asociada a bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Apoptosis , Transducción de Señal , Malondialdehído/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Superóxido Dismutasa/metabolismo , Lactato Deshidrogenasas/metabolismo
6.
PLoS One ; 16(1): e0245581, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33465114

RESUMEN

Evasion of apoptosis is associated with treatment resistance and metastasis in colorectal cancer (CRC). Various cellular processes are associated with evasion of apoptosis. These include overexpression of pro-apoptotic proteins (including p53 and PD-L1), anti-apoptotic proteins (BIRC7/Livin and Bcl-2), chemokine receptors (including DARC), and dysregulation of DNA mismatch repair proteins (including MSH2 and PMS2). The aim of this study was to determine the effect of folinic acid, 5-FU and oxaliplatin (FOLFOX) as a single agent and aspirin plus FOLFOX in various combinations on the aforementioned proteins in human CRC, SW480 cell line and rat models of N-Methyl-N-Nitrosourea (NMU)-induced CRC. In addition, effects of the NMU-induced CRC and chemotherapeutic regimens on haematological and biochemical parameters in the rat models were studied. Immunohistochemistry, immunofluorescence and immunoblot techniques were used to study the expression pattern of the related proteins in the human CRC cells pre- and post-treatment. Double contrast barium enema, post-mortem examination and histological analyses were used to confirm tumour growth and the effect of the treatment in vivo in rat models. Notably, we found in human mucinous CRC, a significant increase in expression of the BIRC7/Livin post-FOLFOX treatment compared with pre-treatment (p = 0.0001). This increase provides new insights into the prognostic role of BIRC7/Livin in evasion of apoptosis and facilitation of treatment resistance, local recurrence and metastasis particularly among mucinous CRCs post-FOLFOX chemotherapy. These poor prognostic features in the CRC may be further compounded by the significant suppression of DARC, PD-L1, PMS2 and overexpression of MSH2 and anti-apoptotic Bcl-2 and p53 proteins observed in our study (p < 0.05). Importantly, we found a significant reduction in expression of BIRC7/Livin and reactivation of DARC and PD-L1 with a surge in Annexin V expression in rat models of CRC cells post-treatment with a sequential dose of aspirin plus FOLFOX compared with other treatments in vivo (p <0.05). The mechanistic rational of these effects underscores the importance of expanded concept of possible aspirin combination therapy with FOLFOX sequentially in future CRC management. Validation of our findings through randomized clinical trials of aspirin plus FOLFOX sequentially in patients with CRC is therefore warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Aspirina/farmacología , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Anexina A5/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Reparación de la Incompatibilidad de ADN/efectos de los fármacos , Interacciones Farmacológicas , Sistema del Grupo Sanguíneo Duffy/metabolismo , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Leucovorina/farmacología , Leucovorina/uso terapéutico , Masculino , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Proteínas de Neoplasias/metabolismo , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/uso terapéutico , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Receptores de Superficie Celular/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Am J Respir Cell Mol Biol ; 63(4): 519-530, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32628869

RESUMEN

KD025 is a ROCK2 inhibitor currently being tested in clinical trials for the treatment of fibrotic lung diseases. The therapeutic effects of KD025 are partly due to its inhibition of profibrotic pathways and fat metabolism. However, whether KD025 affects pulmonary microvascular endothelial cell (PMVEC) function is unknown, despite evidence that alveolar-capillary membrane disruption constitutes major causes of death in fibrotic lung diseases. We hypothesized that KD025 regulates PMVEC metabolism, pH, migration, and survival, a series of interrelated functional characteristics that determine pulmonary barrier integrity. We used PMVECs isolated from Sprague Dawley rats. KD025 dose-dependently decreased lactate production and glucose consumption. The inhibitory effect of KD025 was more potent compared with other metabolic modifiers, including 2-deoxy-glucose, extracellular acidosis, dichloroacetate, and remogliflozin. Interestingly, KD025 increased oxidative phosphorylation, whereas 2-deoxy-glucose did not. KD025 also decreased intracellular pH and induced a compensatory increase in anion exchanger 2. KD025 inhibited PMVEC migration, but fasudil (nonspecific ROCK inhibitor) did not. We tested endothelial permeability in vivo using Evans Blue dye in the bleomycin pulmonary fibrosis model. Baseline permeability was decreased in KD025-treated animals independent of bleomycin treatment. Under hypoxia, KD025 increased PMVEC necrosis as indicated by increased lactate dehydrogenase release and propidium iodide uptake and decreased ATP; it did not affect Annexin V binding. ROCK2 knockdown had no effect on PMVEC metabolism, pH, and migration, but it increased nonapoptotic caspase-3 activity. Together, we report that KD025 promotes oxidative phosphorylation; decreases glycolysis, intracellular pH, and migration; and strengthens pulmonary barrier integrity in a ROCK2-independent manner.


Asunto(s)
Permeabilidad Capilar/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Pulmón/efectos de los fármacos , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Adenosina Trifosfato/metabolismo , Animales , Anexina A5/metabolismo , Movimiento Celular/efectos de los fármacos , Desoxiglucosa/metabolismo , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Glucólisis/efectos de los fármacos , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/metabolismo , Pulmón/metabolismo , Masculino , Fosforilación Oxidativa/efectos de los fármacos , Propidio/farmacología , Ratas , Ratas Endogámicas F344 , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Quinasas Asociadas a rho/metabolismo
8.
Biochim Biophys Acta Biomembr ; 1862(6): 183231, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32119860

RESUMEN

Aging of red blood cells (RBCs) is associated with alteration in a wide range of RBC features, occurring each on its own timescale. A number of these changes are interrelated and initiate a cascade of biochemical and structural transformations, including band-3 clustering and phosphatidylserine (PS) externalization. Using specific band-3 clustering agents (acridine orange (AO) and ZnCl2), we examined whether treatment of RBCs with these agents may affects PS externalization and whether this process is Ca2+-dependent. RBCs were isolated from the blood of eight healthy donors upon obtaining their informed consent. The suspension was supplemented with increasing concentrations of AO or ZnCl2 (from 0.5 to 2.0 mM) and incubated at 25 °C for 60 min. To detect PS at the RBC surface, we used allophycocyanin-conjugated recombinant human Annexin V. We demonstrated, that treatment of RBCs with both clustering agents caused an elevation in the percent of cells positively labeled by Annexin-V (RBCPS), and that this value was not dependent on the presence of calcium in the buffer: RBCs treated with AO in the presence of either EDTA, EGTA or calcium exhibited similar percentage of RBCPS. Moreover, the active influx of Zn2+ into RBCs induced by their co-incubation with both ZnCl2 and A23187 did not increase the percent of RBCPS as compared to RBCs incubated with ZnCl2 alone. Taken together, these results demonstrate that the band-3 clustering agents (AO or ZnCl2) induce PS externalization in a Ca2+ independent manner, and we hereby suggest a possible scenario for this phenomenon.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Análisis por Conglomerados , Eritrocitos/citología , Fosfatidilserinas/metabolismo , Naranja de Acridina/farmacología , Anexina A5/metabolismo , Calcio/farmacología , Senescencia Celular , Cloruros/farmacología , Humanos , Compuestos de Zinc/farmacología
9.
J Biochem Mol Toxicol ; 33(11): e22393, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31518035

RESUMEN

Environmental exposure to lead (Pb) is reported to associate with the development of Alzheimer's disease, where the formation of ß-amyloid peptides (APs) of (1-40), (1-42), and (25-35) is considered as the major risk factor. In this context, we aimed at investigating the effect of epigallocatechin gallate (EGCG), a major flavonoid polyphenol available in green tea, in mitigating the individual and combined toxicity generated by Pb and ß-APs in terms of oxidative stress and apoptosis in human neuronal cells. SH-SY5Y cells were exposed to Pb and ß-APs of (1-40) and (25-35) individually and in different combinations in the presence and absence of EGCG. The results indicated that EGCG mitigated both Pb- and ß-AP-induced oxidative stress in scavenging reactive oxygen species and apoptosis by improving the expression levels of Bax and bcl2 and inhibiting annexin V and caspase-3. Thus, our study shows that EGCG protects SH-SY5Y cells against the cytotoxicity induced by Pb and ß-APs by decreasing oxidative stress and inhibiting apoptosis.


Asunto(s)
Péptidos beta-Amiloides/efectos adversos , Apoptosis/efectos de los fármacos , Catequina/análogos & derivados , Plomo/efectos adversos , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/metabolismo , Anexina A5/metabolismo , Camellia sinensis/química , Caspasa 3/metabolismo , Catequina/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismo
10.
Eur Rev Med Pharmacol Sci ; 23(3): 1047-1054, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30779071

RESUMEN

OBJECTIVE: Cell autophagy reduces the sensitivity of cancer cells to therapeutic reagents in various types of human cancer. Therefore, the aim of our study was to use human colorectal cancer HCT116 cells to explore whether inhibition of autophagy by 3-Methyladenine (3-MA, an autophagy inhibitor) is able to enhance hypoxia-induced apoptosis in vitro. MATERIALS AND METHODS: HCT116 cells were treated with 3-MA, hypoxia, or 3-MA plus hypoxia, and the autophagy, apoptosis and proliferation of the HCT116 cells were investigated. Western blot analysis was used to detect autophagy specificity protein microtubule-associated protein light chain 3 (LC3) expression. Effects on apoptosis were evaluated by using flow cytometry (JC-1 staining to measure mitochondrial membrane potential) and annexin V-propidium iodide (PI) staining. RESULTS: The results showed that the treatment of HCT116 cells in vitro with hypoxia alone increased autophagy as well as apoptosis, whereas combination treatment with 3-MA and hypoxia markedly inhibited hypoxia-induced autophagy, but increased hypoxia-induced cell apoptosis. CONCLUSIONS: Autophagy might play a role as a self-defense mechanism in hypoxia-treated colon cancer cells, and its inhibition could be a promising strategy for the adjuvant chemotherapy of colon cancer.


Asunto(s)
Adenina/análogos & derivados , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Hipoxia/fisiopatología , Adenina/farmacología , Anexina A5/metabolismo , Autofagia/fisiología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas Asociadas a Microtúbulos/biosíntesis
11.
Reprod Sci ; 26(3): 348-356, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29716435

RESUMEN

Deficient expression of the placental anticoagulant annexin A5 (ANXA5) has been associated with thrombophilia-related pregnancy complications and ultimately with recurrent pregnancy loss (RPL). Carrier status of M2/ANXA5 ( RPRGL3), common ANXA5 promoter variant, has been identified as genetic cause of reduced ANXA5 levels and proposed as biomarker for successful anticoagulant treatment of RPL women. A murine model of AnxA5 loss of function displayed characteristic placental pathology and fetal loss that was alleviated through anticoagulant intervention. This study identified an alternative means of supplementing anticoagulation, through elevated ANXA5 expression. Physiological micromolar Zn2+ stimulated ANXA5 transcription, raising ANXA5 protein expression and surface abundance on BeWo and human umbilical vein endothelial cells (HUVEC), thus resulting in prolonged coagulation times. Zn2-fed AnxA5 functionally deficient pregnant mice showed a trend to increase litter size when primiparous that grew comparable to wild-type progeny in subsequent pregnancies. Elevated AnxA5 signal upon Zn2+ treatment was confirmed in murine placentae. Micromolar Zn2+ stimulated ANXA5 expression in cell culture directly and alleviated RPL in AnxA5 genetically deficient mice, without notable toxicity effects.


Asunto(s)
Aborto Habitual/prevención & control , Anexina A5/metabolismo , Anticoagulantes/administración & dosificación , Zinc/administración & dosificación , Aborto Habitual/genética , Animales , Anexina A5/genética , Línea Celular , Femenino , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Placenta/efectos de los fármacos , Placenta/metabolismo , Embarazo
12.
In Vitro Cell Dev Biol Anim ; 55(1): 7-16, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30382494

RESUMEN

The present study was designed to evaluate the effect of SB injection, which is composed of extracts from the roots of Pulsatilla koreana, Panax ginseng, and Glycyrrhiza glabra, on the viability of canine osteosarcoma and melanoma cells and nonneoplastic canine cells. Cells were treated with SB injection, conventional chemotherapeutic drugs, or a combination of both at various concentrations. Cellular viability was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was used to evaluate the cell cycle and apoptosis. SB injection inhibited the growth of osteosarcoma and melanoma cells in a dose-dependent manner. The cell cycle of the affected cells was arrested in the G2/M phase, indicating an anti-proliferative effect. SB injection dose-dependently increased the rate of apoptosis. Furthermore, we found that combining SB injection with chemotherapeutic drugs resulted in a greater reduction in canine malignant cell proliferation than either treatment alone. SB injection did not affect the viability of peripheral blood mononuclear cells regardless of concentration, which suggested that SB injection did not suppress the activity of normal cells. This study suggested that SB injection can be considered an effective alternative medication for animal cancers in veterinary medicine.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/uso terapéutico , Inyecciones , Melanoma/tratamiento farmacológico , Osteosarcoma/tratamiento farmacológico , Animales , Anexina A5/metabolismo , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Cisplatino/uso terapéutico , Perros , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Melanoma/patología , Osteosarcoma/patología , Fitoterapia
13.
J Biochem Mol Toxicol ; 32(10): e22206, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30091159

RESUMEN

Ginger (Zingiber officinale Roscoe), a monocotyledonous herb, is widely used as an herbal medicine owing to the phytoconstituents it possesses. In the current study, the quantity of [6]-gingerol, the major phenolic ketone, in the fresh ginger and dried ginger rhizome was found to be 6.11 µg/mg and 0.407 µg/mg. Furthermore, [6]-gingerol was assessed for its antiapoptotic effects in human gastric adenocarcinoma (AGS) cells evidenced by acridine orange/ethidium bromide staining technique and Annexin-V assay. An increase in reactive oxygen species (ROS) generation led to a decrease in mitochondrial membrane potential (MMP) and subsequent induction of apoptosis. Results disclose that perturbations in MMP are associated with deregulation of Bax/Bcl-2 ratio at protein level, which leads to upregulation of cytochrome-c triggering the caspase cascade. These enduringly suggest that [6]-gingerol can be effectively used for targeting the mitochondrial energy metabolism to manage gastric cancer cells.


Asunto(s)
Adenocarcinoma/patología , Apoptosis/efectos de los fármacos , Catecoles/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Alcoholes Grasos/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/patología , Naranja de Acridina/química , Adenocarcinoma/enzimología , Adenocarcinoma/metabolismo , Anexina A5/metabolismo , Caspasas/metabolismo , Catecoles/análisis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Citocromos c/metabolismo , Etidio/química , Alcoholes Grasos/análisis , Zingiber officinale/química , Humanos , Extractos Vegetales/química , Unión Proteica , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Neoplasias Gástricas/enzimología , Neoplasias Gástricas/metabolismo , Regulación hacia Arriba , Proteína X Asociada a bcl-2/metabolismo
14.
Biomed Pharmacother ; 98: 873-885, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29571258

RESUMEN

Brazilian Northeast is the world's largest producer of Agave sisalana Perrine for the supply of the sisal fiber. About 95% of plant biomass, which comprise the mucilage and sisal juice, is considered a waste residual is discarded in the soil. However, the sisal juice is rich in steroidal saponins, which exhibits different pharmacological properties. Despite this, natural products are not necessarily safe. Based on this, this study analyzed the antioxidant, cytotoxic and mutagenic potential of three extracts derived from acid hydrolysis (AHAS), dried precipitate (DPAS) and hexanic of A. sisalana (HAS). These analyses were performed by in vitro and in vivo methods, using Vero cells, human lymphocytes and mice. Results showed that AHAS 50 and 100 can be considered a useful antineoplastic candidate due to their antioxidant and cytotoxic activity, with no genotoxic/clastogenic potential in Vero cells and mice. Although the comet assay in human lymphocytes has showed that the AHAS 25, AHAS 50 and AHAS 100 can lead to DNA breaks, these extracts did not promote DNA damages in mice bone marrow. Considering the different mutagenic responses obtained with the different methods employed, this study suggest that the metabolizing pathways can produce by-products harmful to health. For this reason, it is mandatory to analyze the mutagenic potential by both in vitro and in vivo techniques, using cells derived from different species and origins.


Asunto(s)
Agave/química , Antioxidantes/farmacología , Eritrocitos/metabolismo , Linfocitos/metabolismo , Mutagénesis , Extractos Vegetales/farmacología , Animales , Anexina A5/metabolismo , Muerte Celular/efectos de los fármacos , Chlorocebus aethiops , Cromatografía Liquida , Ensayo Cometa , Roturas del ADN de Doble Cadena/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Fluoresceínas/metabolismo , Histonas/metabolismo , Humanos , Linfocitos/efectos de los fármacos , Espectrometría de Masas , Ratones , Hojas de la Planta/química , Propidio/metabolismo , Saponinas/análisis , Células Vero
15.
Biogerontology ; 19(2): 159-169, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29363005

RESUMEN

Dietary antioxidants, polyphenols, have been found to be beneficial in protecting against the generation of oxidative stress in various diseases associated with aging. Age-related hearing loss (AHL) is the number one neurodegenerative disorder on our aged population. Sprague-Dawley rats divided into five groups according to their age (3, 6, 12, 18 and 24 months old) and treated with 100 mg/day/kg body weight of polyphenols were used. Then, cochleae were harvested to measure caspase activities (- 3, - 8 and - 9), caspase-3 gene expression, ATP levels, Bax, BcL-2 and p53 levels. 8-OHdG levels (marker of DNA oxidative damage) and annexin-V were also measured in cochleae. Increased levels of caspase-3 and 9 in cochlea were observed with age and this effect was attenuated by polyphenol treatment. In addition, ATP and Bcl-2 levels in older rats were recovered after administration of polyphenols, while Bax and p53 levels protein decreased. Oral supplementation with polyphenols also reduces DNA oxidative damage of cochlear cell. Treatment with polyphenols inhibits the activation of age-related apoptotic signaling by decreasing oxidative stress inside the rat cochlea.


Asunto(s)
Envejecimiento/efectos de los fármacos , Cóclea/efectos de los fármacos , Polifenoles/farmacología , 8-Hidroxi-2'-Desoxicoguanosina , Adenosina Trifosfato/metabolismo , Envejecimiento/metabolismo , Envejecimiento/patología , Animales , Anexina A5/metabolismo , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Cóclea/metabolismo , Cóclea/patología , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Estrés Oxidativo/efectos de los fármacos , Presbiacusia/metabolismo , Presbiacusia/patología , Presbiacusia/prevención & control , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo
16.
Neurotox Res ; 34(1): 147-163, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29124681

RESUMEN

The brain of patients affected by Alzheimer's disease (AD) develops progressive neurodegeneration linked to the formation of proteins aggregates. However, their single actions cannot explain the extent of brain damage observed in this disorder, and the characterization of co-adjuvant involved in the early toxic processes evoked in AD is essential. In this line, quinolinic acid (QUIN) and homocysteine (Hcy) appear to be involved in the AD neuropathogenesis. Herein, we investigate the effects of QUIN and Hcy on early toxic events in cortical neurons and astrocytes. Exposure of primary cortical cultures to these neurometabolites for 24 h induced concentration-dependent neurotoxicity. In addition, QUIN (25 µM) and Hcy (30 µM) triggered ROS production, lipid peroxidation, diminished of Na+,K+-ATPase activity, and morphologic alterations, culminating in reduced neuronal viability by necrotic cell death. In astrocytes, QUIN (100 µM) and Hcy (30 µM) induced caspase-3-dependent apoptosis and morphologic alterations through oxidative status imbalance. To establish specific mechanisms, we preincubated cell cultures with different protective agents. The combined toxicity of QUIN and Hcy was attenuated by melatonin and Trolox in neurons and by NMDA antagonists and glutathione in astrocytes. Cellular death and morphologic alterations were prevented when co-culture was treated with metabolites, suggesting the activation of protector mechanisms dependent on soluble factors and astrocyte and neuron communication through gap junctions. These findings suggest that early damaging events involved in AD can be magnified by synergistic toxicity of the QUIN and Hcy. Therefore, this study opens new possibilities to elucidate the molecular mechanisms of neuron-astrocyte interactions and their role in neuroprotection against QUIN and Hcy.


Asunto(s)
Astrocitos/efectos de los fármacos , Corteza Cerebral/citología , Homocisteína/farmacología , Neuronas/efectos de los fármacos , Neurotoxinas/farmacología , Ácido Quinolínico/farmacología , Análisis de Varianza , Animales , Anexina A5/metabolismo , Astrocitos/ultraestructura , Células Cultivadas , Técnicas de Cocultivo , Sinergismo Farmacológico , Embrión de Mamíferos , Femenino , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Proteínas del Tejido Nervioso/metabolismo , Neuronas/ultraestructura , Embarazo , Ratas , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico
17.
Transfusion ; 58(1): 25-33, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29119573

RESUMEN

BACKGROUND: Room temperature (RT) storage of platelets (PLTs) can support bacterial proliferation in contaminated units, which can lead to transfusion-transmitted septic reactions. Cold temperature storage of PLTs could reduce bacterial proliferation but cold exposure produces activation-like changes in PLTs and leads to their rapid clearance from circulation. Cold-induced changes are reversible by warming and periodic rewarming during cold storage (temperature cycling [TC]) has been proposed to alleviate cold-induced reduction in PLT circulation. STUDY DESIGN AND METHODS: A clinical trial in healthy human volunteers was designed to compare in vivo recovery, survival, and area under the curve (AUC) of radiolabeled autologous apheresis PLTs stored for 7 days at RT or under TC or cold conditions. Paired comparisons of RT versus TC and TC versus cold PLTs were conducted. RESULTS: Room temperature PLTs had in vivo recovery of 55.7 ± 13.9%, survival of 161.3 ± 28.8 hours, and AUC of 5031.2 ± 1643.3. TC PLTs had recovery of 42.6 ± 16.4%, survival of 48.1 ± 14.4% hours, and AUC of 1331.3 ± 910.2 (n = 12, p < 0.05). In a separate paired comparison, cold PLTs had recovery of 23.1 ± 8.8%, survival of 33.7 ± 14.7 hours, and AUC of 540.2 ± 229.6 while TC PLTs had recovery of 36.5 ± 12.9%, survival of 49.0 ± 17.3 hours, and AUC of 1164.3 ± 622.2 (n = 4, AUC had p < 0.05). CONCLUSION: TC storage for 7 days produced PLTs with better in vivo circulation kinetics than cold storage but is not equivalent to RT storage.


Asunto(s)
Plaquetas/citología , Conservación de la Sangre/métodos , Criopreservación/métodos , Transfusión de Plaquetas , Temperatura , Adenosina Difosfato/farmacología , Anexina A5/metabolismo , Área Bajo la Curva , Plaquetas/efectos de los fármacos , Transfusión de Sangre Autóloga , Forma de la Célula , Supervivencia Celular , Colágeno/farmacología , Voluntarios Sanos , Humanos , Concentración de Iones de Hidrógeno , Soluciones Preservantes de Órganos/química , Selectina-P/sangre , Activación Plaquetaria/efectos de los fármacos , Complejo GPIb-IX de Glicoproteína Plaquetaria/análisis , Factores de Tiempo
18.
Biomed Pharmacother ; 98: 76-81, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29245069

RESUMEN

Triphala (Trl) is an ayurvedic formulation used for treating disorders of the digestive, respiratory, and nervous systems. Its anticancer properties have also been documented. We studied effects of Trl on tubulin, a target protein for several anticancer drugs, and systematically elucidated a possible antiproliferative mechanism of action of Trl. Trl inhibited proliferation of HeLa (cervical adenocarcinoma), PANC-1 (pancreatic adenocarcinoma), and MDA-MB-231 (triple-negative breast carcinoma) cells in microgram quantities and strongly suppressed the clonogenicity of HeLa cells. The formulation disrupted secondary conformation of tubulin and inhibited anilino naphthalene sulfonate binding to tubulin. In cells, Trl-tubulin interactions were manifested as a perturbed microtubule network. Acetylation pattern of Trl-treated cellular microtubules indicated persistent stabilization of microtubule dynamics. In addition, Trl interfered with reassembly of the microtubules. Cells treated with Trl eventually underwent programmed cell death as evidenced by annexin-V staining. Our study shows that the effect of aqueous extract of Trl is potent enough to interfere with the assembly dynamics of microtubules, and that Trl can be investigated further for its antitumor potential.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Microtúbulos/efectos de los fármacos , Extractos Vegetales/farmacología , Anexina A5/metabolismo , Línea Celular Tumoral , Células HeLa , Humanos , Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo
19.
Integr Cancer Ther ; 16(3): 414-425, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28818030

RESUMEN

Cancers involving the oral cavity, head, and neck regions are often treated with cisplatin. In cancer therapy, the main target is to eliminate unwanted cancerous cells. However, reports on the nonselective nature of this drug have raised few concerns. Incorrect nutritional habits and lifestyle practices have been directly linked to cancer incidence. Nutrients with antioxidant activity inhibit cancer cells development, destroying them through oxidative stress and apoptosis. α-tocopherol, the potent antioxidant form of vitamin E is a known scavenger of free radicals. In vitro study exhibited effective antitumor activity of α-tocopherol on ORL-48 at 2.5 ± 0.42 µg/mL. Cisplatin exhibited stronger activity at 1.0 ± 0.15 µg/mL, but unlike α-tocopherol it exhibited cytotoxicity on normal human epidermal keratinocytes at very low concentration (<0.1 µg/mL). Despite the lower potency of α-tocopherol, signs of apoptosis such as the shrinkage of cells and appearance of apoptotic bodies were observed much earlier than cisplatin in time lapse microscopy. No apoptotic vesicles were formed with cisplatin, instead an increased population of cells in the holoclone form which may suggest different induction mechanisms between both agents. High accumulation of cells in the G0/G1 phase were observed through TUNEL and annexin V-biotin assays, while the exhibition of ultrastructural changes of the cellular structures verified the apoptotic mode of cell death by both agents. Both cisplatin and α-tocopherol displayed cell cycle arrest at the Sub G0 phase. α-tocopherol thus, showed potential as an antitumour agent for the treatment of oral cancer and merits further research.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Vitamina E/farmacología , alfa-Tocoferol/farmacología , Anexina A5/metabolismo , Antioxidantes/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Cisplatino/farmacología , Fase G1/efectos de los fármacos , Humanos , Estrés Oxidativo/efectos de los fármacos , Fase de Descanso del Ciclo Celular/efectos de los fármacos
20.
Biomed Pharmacother ; 89: 1216-1226, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28320088

RESUMEN

Cervical cancer accounts for the second most frequent cancer and also third leading cause of cancer mortality (15%) among women worldwide. The major problems of chemotherapeutic treatment in cervical cancer are non-specific cytotoxicity and drug resistance. Plant-derived products, known as natural therapies, have been used for thousands of years in cancer treatment with a very low number of side effects. Allium atroviolaceum is a species in the genus Allium and Liliaceae family, which could prove to have beneficial effects on cancer treatment, although there is a lack of corresponding attention. The methanolic extract from the A.atroviolaceum flower displayed marked anticancer activity on HeLa human cervix carcinoma cells with much lower cytotoxic effects on normal cells (3T3). The A.atroviolaceum extract induced apoptosis, confirmed by cell cycle arrest at the sub-G0 (apoptosis) phase, characteristic morphological changes, evident DNA fragmentation, observed by fluorescent microscope, and early and late apoptosis detection by Annexin V. Furthermore, down-regulation of Bcl-2 and activation of caspase-9 and -3 strongly indicated that the mitochondrial pathway was involved in the apoptosis signal pathway. Moreover, combination of A.atroviolaceum extract with doxorubicin revealed a significant reduction of IC50 and led to a synergistic effect. In summary, A.atroviolaceum displayed a significant anti-tumour effect through apoptosis induction in HeLa cells, suggesting that the A.atroviolaceum flower might have therapeutic potential against cervix carcinoma.


Asunto(s)
Allium/química , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Flores/química , Extractos Vegetales/farmacología , Proteína X Asociada a bcl-2/metabolismo , Anexina A5/metabolismo , Antineoplásicos/farmacología , Caspasa 9/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Células HeLa , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Transducción de Señal/efectos de los fármacos
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