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1.
J Vis Exp ; (165)2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-33283783

RESUMEN

Brain microvascular endothelial cells (BMECs) can be differentiated from human induced pluripotent stem cells (iPSCs) to develop ex vivo cellular models for studying blood-brain barrier (BBB) function. This modified protocol provides detailed steps to derive, expand, and cryopreserve BMECs from human iPSCs using a different donor and reagents than those reported in previous protocols. iPSCs are treated with essential 6 medium for 4 days, followed by 2 days of human endothelial serum-free culture medium supplemented with basic fibroblast growth factor, retinoic acid, and B27 supplement. At day 6, cells are sub-cultured onto a collagen/fibronectin matrix for 2 days. Immunocytochemistry is performed at day 8 for BMEC marker analysis using CLDN5, OCLN, TJP1, PECAM1, and SLC2A1. Western blotting is performed to confirm BMEC marker expression, and absence of SOX17, an endodermal marker. Angiogenic potential is demonstrated with a sprouting assay. Trans-endothelial electrical resistance (TEER) is measured using chopstick electrodes and voltohmmeter starting at day 7. Efflux transporter activity for ATP binding cassette subfamily B member 1 and ATP binding cassette subfamily C member 1 is measured using a multi-plate reader at day 8. Successful derivation of BMECs is confirmed by the presence of relevant cell markers, low levels of SOX17, angiogenic potential, transporter activity, and TEER values ~2000 Ω x cm2. BMECs are expanded until day 10 before passaging onto freshly coated collagen/fibronectin plates or cryopreserved. This protocol demonstrates that iPSC-derived BMECs can be expanded and passaged at least once. However, lower TEER values and poorer localization of BMEC markers was observed after cryopreservation. BMECs can be utilized in co-culture experiments with other cell types (neurons, glia, pericytes), in three-dimensional brain models (organ-chip and hydrogel), for vascularization of brain organoids, and for studying BBB dysfunction in neuropsychiatric disorders.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/citología , Criopreservación , Células Endoteliales/citología , Células Madre Pluripotentes Inducidas/citología , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Biomarcadores/metabolismo , Barrera Hematoencefálica/citología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Colágeno Tipo IV/farmacología , Impedancia Eléctrica , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Fibronectinas/farmacología , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Neovascularización Fisiológica/efectos de los fármacos
2.
J Coll Physicians Surg Pak ; 28(10): 731-734, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30266113

RESUMEN

OBJECTIVE: To determine the effects of lead acetate and Ficus carica on disruption of basement membrane in seminiferous tubules of adult rat testis. STUDY DESIGN: An experimental study. PLACE AND DURATION OF STUDY: Department of Anatomy, Army Medical College, Rawalpindi in collaboration with National Institute of Health (NIH), Islamabad, from March to November 2017. METHODOLOGY: Thirty male adult Sprague Dawley rats were selected and divided into three groups, each with ten animals. All treatments were given once daily for a period of eight weeks. Control was labelled as group A. Group B was administered lead acetate at a dose of 30 mg/kg body weight. Group C was treated with lead acetate at a dose of 30 mg/kg body weight and Ficus carica at a dose of 80 mg/kg body weight. Animals were dissected 24 hours after the last dose. Testis were treated, fixed and stained for histological study. Disruption of basement membrane in seminiferous tubules was scored morphometrically on a scale of 0 (normal) to 3 (>70% tubules showing disruption) and statistically analysed. RESULTS: Significant number of seminiferous tubules showed disruption of basement membrane in group B (20%) as compared to group A (0%). Less severe disruption of membrane was seen in group C as compared to group B, which was statistically not significant (p=0.082). CONCLUSION: Lead acetate causes significant disruption of basement membrane in seminiferous tubules of testis of adult rats but subsequent administration of Ficus carica reduces the effects on short term.


Asunto(s)
Membrana Basal/efectos de los fármacos , Ficus/química , Compuestos Organometálicos/efectos adversos , Extractos Vegetales/farmacología , Túbulos Seminíferos/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/patología , Testículo/patología
3.
Chin J Integr Med ; 24(8): 600-605, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27778266

RESUMEN

OBJECTIVE: To evaluate the renal protective effect of Tangshenkang Granule () in a rat model of diabetic nephropathy (DN). METHODS: Forty male Sprague-Dawley rats were randomly divided into control, DN, Tangshenkang and benazepril groups. DN model was established in the rats of DN, Tangshenkang and benazepril groups. Tangshenkang Granule solution and benazepril hydrochloride solution were intragastrically administered daily to the rats in the Tangshenkang and benazepril groups for 8 weeks, respectively. Urinary albumin and creatinine were detected. The albumin/creatinine (ACR) was calculated in addition to 24 h urinary protein (24-h UPr), serum creatinine (Scr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and creatinine clearance rate (Ccr). Right kidneys were harvested for pathological observation using periodic acid-silver methenamine-Masson staining. The average glomerular diameter (DG), average glomerular (AG) and mesangial areas (AM) were measured. The thickness of glomerular basement membrane (TGBM) was detected using transmission electron microscope. RESULTS: Compared with rats in the control group, rats in the DN group showed significantly decreased body weight, increased hypertrophy index, 24-h urinary volume, 24-h UPr, ACR, Scr, BUN, Ccr, blood lipids as well as renal pathological indices including DG, AG, AM, AM/AG and TGBM (P <0.05). Compared with the DN group, the weights of rats in the Tangshenkang and benazepril groups were significantly increased, and the renal hypertrophy indices were significantly decreased (P <0.05). The 24-h urinary volumes, ACR, 24-h UPr, Scr, BUN, Ccr, LDL, DG, AG, AM and TGBM were obviously decreased (P <0.05). Compared with the benazepril group, the Tangshenkang group showed significantly decreased levels of ACR, 24-h UPr, AG and AM (P <0.05). CONCLUSIONS: Tangshenkang Granule decreased the urinary protein, attenuated the high glomerular filtration rate and improved lipid metabolism in DN rats, and prevented further injury induced by diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Albuminuria/complicaciones , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Nitrógeno de la Urea Sanguínea , Peso Corporal/efectos de los fármacos , Creatinina/sangre , Creatinina/orina , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/fisiopatología , Nefropatías Diabéticas/orina , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Hipertrofia , Pruebas de Función Renal , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/patología , Glomérulos Renales/fisiopatología , Metabolismo de los Lípidos/efectos de los fármacos , Lípidos/sangre , Masculino , Ratas Sprague-Dawley
4.
Aging (Albany NY) ; 9(11): 2302-2315, 2017 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-29176034

RESUMEN

Skin is constantly exposed to environmental factors such as pollutants, chemicals and ultra violet radiation (UV), which can induce premature skin aging and increase the risk of skin cancer. One strategy to reduce the effect of oxidative stress produced by environmental exposure is the application of antioxidant molecules. Among the endogenous antioxidants, selenoproteins play a key role in antioxidant defense and in maintaining a reduced cellular environment. Selenium, essential for the activity of selenoproteins, is a trace element that is not synthesized by organisms and must be supplied by diet or supplementation. The aim of this study is to evaluate the effect of Selenium supplementation on skin aging, especially on keratinocytes, the main cells of the epidermis. Our results demonstrate for the first time to our knowledge, the major role of Selenium on the replicative life span of keratinocytes and on aging skin. Selenium protects keratinocyte stem cells (KSCs) against senescence via preservation of their stemness phenotype through adhesion to the basement membrane. Additionally, Selenium supplementation maintains the homeostasis of skin during chronological aging in our senescent skin equivalent model. Controlled supplementation with Selenium could be a new strategy to protect skin against aging.


Asunto(s)
Antioxidantes/farmacología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Senescencia Celular/efectos de los fármacos , Epidermis/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Envejecimiento de la Piel/efectos de los fármacos , Selenito de Sodio/farmacología , Células Madre/efectos de los fármacos , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Epidermis/metabolismo , Humanos , Queratinocitos/metabolismo , Fenotipo , Células Madre/metabolismo , Factores de Tiempo
5.
Phytomedicine ; 23(7): 686-93, 2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-27235707

RESUMEN

BACKGROUND: Farrerol is one of traditional Chinese medicines, isolated from Rhododendron dauricum L. It has been reported that Farrerol exerts multiple biological activities. Angiogenesis is an important drug target for cancer and inflammation therapy, the effect of Farrerol on angiogenesis is unknown. HYPOTHESIS/PURPOSE: We aimed to investigate whether Farrerol may have inhibitory effects against angiogenesis. STUDY DESIGN/METHODS: Two kinds of endothelial cells, named human umbilical vein endothelia cell and human micro vessel endothelial cells, were used to examine the effect and mechanism of Farrerol on angiogenesis. MTT assay was used to detect cell proliferation, wound healing assay and boyden's chamber assay were used to examine cell migration, Matrigel was used as basement membrane substratum in tube formation assay, Annexin V-FITC/PI dual staining assay and trypan blue staining were used to detect cell apoptosis, mouse aortic rings assay was performed as ex vivo assay, the expression of proteins involved in angiogenesis was tested using western blot, the binding of Farrerol to Stat3 was monitored by docking assay, molecular dynamics simulations and MM-GBSA method. RESULTS: Farrerol showed an inhibitory effect on proliferation, migration and tube formation of human umbilical vein endothelia cell and human micro vessel endothelial cells in a concentration-dependent manner. Farrerol induced cell cycle arrest and increased the apoptotic percentage of endothelial cells. Farrerol also suppressed the formation of new micro vessels from mouse aortic rings. Moreover, Farrerol reduced the phosphorylation levels of Erk, Akt, mTOR, Jak2 and Stat3 as well as protein expression of Bcl-2 and Bcl-xl. Docking assay, molecular dynamics simulations and MM-GBSA method showed that Farrerol bound to domain of Stat3, Ser613,Gln635, Glu638 and Thr714 are the main residues in Farrerol binding sites with the binding free energy -7.3 ∼ -9.0kcal/mol. CONCLUSIONS: In this study, we demonstrated that Farrerol inhibited angiogenesis through down regulation of Akt/mTOR, Erk and Jak2/Stat3 signal pathway. The inhibitory effect of Farrerol on angiogenesis suggested that this compound may be helpful to the angiogenesis-related diseases treatment, such as cancer and inflammations.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Cromonas/farmacología , Janus Quinasa 2/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Factor de Transcripción STAT3/efectos de los fármacos , Serina-Treonina Quinasas TOR/efectos de los fármacos , Animales , Aorta Torácica/efectos de los fármacos , Membrana Basal/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Técnicas In Vitro , Ratones , Transducción de Señal/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos
6.
Toxins (Basel) ; 8(4): 93, 2016 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-27023608

RESUMEN

The historical development of discoveries and conceptual frames for understanding the hemorrhagic activity induced by viperid snake venoms and by hemorrhagic metalloproteinases (SVMPs) present in these venoms is reviewed. Histological and ultrastructural tools allowed the identification of the capillary network as the main site of action of SVMPs. After years of debate, biochemical developments demonstrated that all hemorrhagic toxins in viperid venoms are zinc-dependent metalloproteinases. Hemorrhagic SVMPs act by initially hydrolyzing key substrates at the basement membrane (BM) of capillaries. This degradation results in the weakening of the mechanical stability of the capillary wall, which becomes distended owing of the action of the hemodynamic biophysical forces operating in the circulation. As a consequence, the capillary wall is disrupted and extravasation occurs. SVMPs do not induce rapid toxicity to endothelial cells, and the pathological effects described in these cells in vivo result from the mechanical action of these hemodynamic forces. Experimental evidence suggests that degradation of type IV collagen, and perhaps also perlecan, is the key event in the onset of microvessel damage. It is necessary to study this phenomenon from a holistic, systemic perspective in which the action of other venom components is also taken into consideration.


Asunto(s)
Hemorragia/inducido químicamente , Metaloendopeptidasas/toxicidad , Proteínas de Reptiles/toxicidad , Venenos de Víboras/enzimología , Animales , Membrana Basal/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Hemorragia/patología , Microvasos/efectos de los fármacos , Microvasos/patología
7.
Zhongguo Zhong Yao Za Zhi ; 39(3): 478-82, 2014 Feb.
Artículo en Chino | MEDLINE | ID: mdl-24946551

RESUMEN

OBJECTIVE: To investigate the effect of Moutan Cortex on mesangial proliferation and basement membrane thickening induced by advanced glycation end products (AGEs). METHOD: The glomerular mesangial cells (MC) injury model was established by inducing by AGEs. The cell were divided into 6 groups: the blank group ( BSA, 200 mg L-1) , the model group (AGEs, 200 mg L-1), the positive control group (AG, 10 mmol L L-1), and drug administration groups, namely the Moutan Cortex-treated high-dose group (2 x 10(-4) g mL(- 1)), the Moutan Cortex-treated medium-dose group (1 x 10(-4) g mL-1 ), and the Moutan Cortex-treated low-dose group (0. 5 x 10(-4) g . mL(-1)). The MTT method was performed to observe the effect of Moutan Cortex on the proliferation of MC. The content of fibronectin (FN) and collagen secretion 1V (Col IV) in cell supernatant were detected by ELISA kits. The western blot analysis was carried out to observe the FN expression. The Real-time PCR analysis was applied to examine the Col IV mRNA expression. RESULT: AGEs significantly increased AGEs-induced MC proliferation and FN and Col 1V secretion. The western blot analysis showed that MC could down-regulate the FN expression of MC secretion. According to the results of the real-time PCR assay, MC could down-regulate AGEs-induced MC secretion Col IV mRNA expression. CONCLUSION: MC had a certain protective effect on MC cultured under AGEs conditions. MC could remarkably inhibit the composition and secretion of Col IV and FN in matrix and the basement membrane thickening, and provide an experimental basis for the treatment of diabetic nephropathy.


Asunto(s)
Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Medicamentos Herbarios Chinos/farmacología , Productos Finales de Glicación Avanzada/efectos adversos , Células Mesangiales/citología , Células Mesangiales/efectos de los fármacos , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Fibronectinas/biosíntesis , Regulación de la Expresión Génica/efectos de los fármacos , Células Mesangiales/metabolismo , Paeonia
8.
J Pediatr Surg ; 49(1): 61-5; discussion 65, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24439582

RESUMEN

PURPOSE: The lungs of infants born with congenital diaphragmatic hernia suffer from immaturity as well as the short and long term consequences of ventilator-induced lung injury, including chronic lung disease. Antenatal and postnatal steroids are among current strategies promoted to treat premature lungs and limit long term morbidity. Although studied in whole-animal models, insight into ventilator-induced injury at the alveolar-capillary interface as well as the benefits of steroids, remains limited. The present study utilizes a multi-fluidic in vitro model of the alveolar-interface to analyze membrane disruption from compressive aerodynamic forces in dexamethasone-treated cultures. METHODS: Human alveolar epithelial cell lines, H441 and A549, were cultured in a custom-built chamber under constant aerodynamic shear followed by introduction of pressure stimuli with and without dexamethasone (0.1µM). On-chip bioelectrical measurements were noted to track changes to the cellular surface and live-dead assay to ascertain cellular viability. RESULTS: Pressure-exposed alveolar cultures demonstrated a significant drop in TEER that was less prominent with an underlying extracellular-matrix coating. Addition of dexamethasone resulted in increased alveolar layer integrity demonstrated by higher TEER values. Furthermore, dexamethasone-treated cells exhibited faster recovery, and the effects of pressure appeared to be mitigated in both cell types. CONCLUSION: Using a novel in vitro model of the alveolus, we demonstrate a dose-response relationship between pressure application and loss of alveolar layer integrity. This effect appears to be alleviated by dexamethasone and matrix sub-coating.


Asunto(s)
Barotrauma/prevención & control , Dexametasona/farmacología , Alveolos Pulmonares/efectos de los fármacos , Lesión Pulmonar Inducida por Ventilación Mecánica/prevención & control , Aire , Presión del Aire , Membrana Basal/efectos de los fármacos , Técnicas de Cultivo de Célula/instrumentación , Línea Celular , Membrana Celular/efectos de los fármacos , Supervivencia Celular , Colágeno , Dexametasona/administración & dosificación , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Evaluación Preclínica de Medicamentos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Humanos , Laminina , Proteoglicanos , Alveolos Pulmonares/citología , Reología/instrumentación , Propiedades de Superficie
9.
J Oral Pathol Med ; 43(7): 484-91, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24450492

RESUMEN

OBJECTIVE: Cancer chemoprevention is defined as the use of chemicals or dietary components to block, inhibit, or reverse the development of cancer in normal or pre-neoplastic tissue. Mentha extract (ME) has antioxidant and antiperoxidant properties. This study was held to investigate the protective and anticancer effect of Mentha leaves aqueous extract on oral epithelium of mice tongues. DESIGN: A total of 80 Egyptian albino mice were divided into three groups. Group I served as control (not subjected to any kind of treatment), and groups II and III were subjected to two-stage chemical carcinogenesis through topical application of dimethylbenz[a]anthracene (DMBA) followed by formaldehyde on dorsal and ventral surfaces of tongues for 9 weeks. Mentha leaves extract was administrated to group III at the same time of cancer induction. Histological changes were assessed in H&E sections at 3-week intervals. The anticarcinogenic effect of Mentha piperita was tested using immunostain with anticaspase antibody. RESULTS: The oral administration of ME reduced the appearance of dysplastic cellular changes with 61% and inhibited tumor incidence with 100%. Group I showed moderate-to-strong cytoplasmic caspase expression. At 6-week interval, group II showed weak-to-moderate caspase expression, while sections from group III showed moderate-to-strong caspase expression. High significant statistical difference in the total score of caspase 3 expression was found between specimens obtained from animals sacrificed at 6 weeks in groups I, II, and III (P = 0.001**). CONCLUSION: Our study demonstrated that Mentha piperita has inhibited the initiation and promotion of oral dysplastic lesions.


Asunto(s)
9,10-Dimetil-1,2-benzantraceno/efectos adversos , Anticarcinógenos/uso terapéutico , Carcinogénesis/efectos de los fármacos , Carcinógenos/farmacología , Formaldehído/efectos adversos , Mentha piperita , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Neoplasias de la Lengua/prevención & control , Animales , Antioxidantes/uso terapéutico , Membrana Basal/efectos de los fármacos , Membrana Basal/patología , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/prevención & control , Caspasa 3/análisis , Quimioprevención , Tejido Conectivo/efectos de los fármacos , Tejido Conectivo/patología , Epitelio/efectos de los fármacos , Epitelio/patología , Hiperplasia , Queratinas , Masculino , Ratones , Sustancias Protectoras/uso terapéutico , Lengua/efectos de los fármacos , Lengua/patología , Neoplasias de la Lengua/inducido químicamente , Neoplasias de la Lengua/patología
10.
Mol Vis ; 19: 1999-2010, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24146535

RESUMEN

PURPOSE: To investigate the potential protective effects of total flavonoids from Flos Puerariae (TFF) on retinal neural cells in diabetic mice. METHODS: C57BL/6J mice were intraperitoneally injected with streptozotocin to generate type I diabetes in a murine model, as indicated by blood glucose levels ≥11.1 mmol/l. TFF was administered intragastrically at a dose of 50, 100, or 200 mg/kg/day. After 10 weeks of administration, the mice were euthanized, and the eyes were dissected. Retinal histology was examined, and the thickness of the retina was measured. Ultrastructural changes in the retinal ganglion cells and capillary basement membrane were observed with electron microscopy. Apoptosis of retinal neural cells was determined with the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay. Bax and Bcl-2 expression in the retinal tissues was determined with immunohistochemical staining and western blotting. RESULTS: Compared with the diabetic mice, the blood glucose level decreased (p<0.01) and the bodyweight increased (p<0.05) in the 100 and 200 mg/kg TFF-treated groups. The thickness of the retina significantly increased (p<0.01), and the retinal capillary basement membrane (BM) thickness was reduced in the 100 and 200 mg/kg TFF-treated diabetic mice (DM). The 100 and 200 mg/kg TFF treatments also attenuated the diabetes-induced apoptosis of retinal neural cells. Consistent with these effects, TFF treatment decreased the Bax expression level and, concurrently, increased the ratio of Bcl-2 to Bax. CONCLUSIONS: TFF attenuated diabetes-induced apoptosis in retinal neurons by inhibiting Bax expression and increasing the ratio of Bcl-2 to Bax, which suggests that TFF might prevent retinal neuronal damage in diabetes mellitus.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/patología , Medicamentos Herbarios Chinos/farmacología , Flavonoides/farmacología , Fármacos Neuroprotectores/farmacología , Neuronas Retinianas/efectos de los fármacos , Neuronas Retinianas/patología , Animales , Apoptosis/efectos de los fármacos , Membrana Basal/efectos de los fármacos , Membrana Basal/patología , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Capilares/efectos de los fármacos , Capilares/patología , Diabetes Mellitus Experimental/sangre , Progresión de la Enfermedad , Medicamentos Herbarios Chinos/uso terapéutico , Flavonoides/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/uso terapéutico , Pueraria , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/ultraestructura , Neuronas Retinianas/metabolismo , Neuronas Retinianas/ultraestructura , Estreptozocina , Pérdida de Peso/efectos de los fármacos , Proteína X Asociada a bcl-2/metabolismo
11.
Chin Med J (Engl) ; 126(9): 1693-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23652053

RESUMEN

BACKGROUND: Poly(ADP-ribose) polymerase (PARP) plays an important role in the death of retinal capillary cells in diabetic retinopathy (DR) partly via its regulation of nuclear factor kappa B (NF-κB). The current study investigated the effect of the regimen of Gaoshan Hongjingtian (RG) on the mechanism of PARP regulation of NF-κB, and demonstrated the possible impact of the RG and Gaoshan Hongjingtian (Rhodiola sachalinensis, RS) on diabetic retinopathy. METHODS: Wistar rats were made diabetic by administering streptozotocin. They were then assigned to three groups at random. After 2 months, the three groups of these diabetic rats were treated with RS or RG, or untreated. Analyses of expression levels of PARP, NF-κB, and intercellular adhesion molecule-1 (ICAM-1) in the retinas of rats in different groups were performed by Western blotting and immunohistochemical assays, and mRNA levels of NF-κB and ICAM-1 were determined by real-time polymerase chain reaction (PCR). In addition, the basement membranes of capillaries in the rats' retinas were observed using electron microscopy, and diabetes-induced capillary degeneration (ghost pericytes and acellular capillaries) were quantitated. RESULTS: From the third month after the injection of streptozotocin, the diabetic rats were given daily RG, RS or tap water separately. The diabetic rats failed to gain weight compared with normal age-matched rats, whereas their glycated hemoglobin levels were significantly increased. After 5 months, the mRNA levels of NF-κB and ICAM-1 and the protein expression of PARP, NF-κB, and ICAM-1 were significantly increased in the retinas of diabetic rats in the untreated group compared with the nondiabetic controls. After 8 months, the number of degenerated retinal capillaries (ghost pericytes and acellular capillaries) was significantly increased in the diabetic rats in the untreated group compared with normal age-matched rats. RG and RS inhibited diabetes-induced over-expression of PARP, NF-κB, and ICAM-1 in the retinas of diabetic rats at the end of 5-month diabetic duration. Treatment using RG and RS significantly inhibited increases in the number of acellular capillaries and pericyte ghosts and suppressed the basement membrane thickening in the retinas of rats with diabetes for 8 months compared with the control diabetic rats. CONCLUSIONS: These results indicate that PARP plays an important role in the pathogenesis of diabetic retinopathy. RS and RG may have acted on the mechanism of PARP regulation of NF-κB, which suppressed the expression of NF-κB and ICAM-1, and led to the inhibition of retinal capillary degeneration.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Medicina Tradicional China , FN-kappa B/fisiología , Poli(ADP-Ribosa) Polimerasas/fisiología , Rhodiola , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/patología , Diabetes Mellitus Experimental/patología , Retinopatía Diabética/patología , Molécula 1 de Adhesión Intercelular/genética , Masculino , FN-kappa B/genética , Ratas , Ratas Wistar , Estreptozocina
12.
J Ocul Pharmacol Ther ; 29(4): 419-26, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23215831

RESUMEN

PURPOSE: The present study was aimed to evaluate the retinoprotective effects of Moringa oleifera (MO) in Streptozotocin-induced diabetic rats. METHODS: The study was continued for 24 weeks and evaluated for inflammatory (tumor necrosis factor [TNF]-α and interleukin [IL]-1ß, angiogenic (vascular endothelial growth factor [VEGF] and protein kinase C [PKC]-ß) and antioxidant (Glutathione, Superoxide dismutase, and Catalase) parameters. Retinal leakage was checked by Fluorescein angiography (FA) and fundus photographs were evaluated for retinal vessel caliber (arteriolar and venular). Transmission electron microscopy was done to determine basement membrane (BM) thickness. RESULTS: The results of the present study showed potential hypoglycemic and retinal antioxidant effects of MO. In the present study, a significant rise in the expression of retinal inflammatory (TNF-α and IL-1ß) and angiogenic (VEGF and PKC-ß) parameters was observed in diabetic retinae as compared to normal retinae. However, MO-treated retinae showed marked inhibition in the expression of inflammatory and angiogenic parameters. Further, in the present study, diabetic retinae showed dilated retinal vessels as compared to normal. However, MO-treated retinae showed marked prevention in the dilatation of retinal vessels. Fluorescein angiograms obtained from diabetic retinae showed leaky and diffused retinal vasculature. On the other hand, MO-treated retinae showed intact retinal vasculature. Further, results of the transmission electron microscopy study showed thickened capillary BM in the diabetic retina as compared to normal retinae. However, treatment with MO prevented thickening of capillary BM. CONCLUSION: Our result suggests that MO may be useful in preventing diabetes induced retinal dysfunction.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Retinopatía Diabética/prevención & control , Moringa oleifera/química , Extractos Vegetales/farmacología , Inhibidores de la Angiogénesis/aislamiento & purificación , Inhibidores de la Angiogénesis/farmacología , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/fisiopatología , Retinopatía Diabética/patología , Femenino , Inflamación/etiología , Inflamación/prevención & control , Masculino , Microscopía Electrónica de Transmisión , Ratas , Ratas Wistar , Retina/efectos de los fármacos , Retina/metabolismo , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/metabolismo , Estreptozocina
13.
Iran J Allergy Asthma Immunol ; 11(4): 316-23, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23264408

RESUMEN

Hedera helix is widely used to treat bronchial asthma for many years. However, effects of this herb on lung histopathology is still far from clear. We aimed to determine the effect of oral administration of Hedera helix on lung histopathology in a murine model of chronic asthma.BALB/c mice were divided into four groups; I (Placebo), II (Hedera helix), III (Dexamethasone) and IV (Control). All mice except controls were sensitized and challenged with ovalbumin. Then, mice in group I received saline, group II 100 mg/kg Hedera helix and group III 1 mg/kg dexamethasone via orogastic gavage once daily for one week. Airway histopathology was evaluated by using light and electron microscopy in all groups.Goblet cell numbers and thicknesses of basement membrane were found significantly lower in group II, but there was no statistically significant difference in terms of number of mast cells, thicknesses of epithelium and subepithelial smooth muscle layers between group I and II. When Hedera helix and dexamethasone groups were compared with each other, thickness of epithelium, subepithelial muscle layers, number of mast cells and goblet cells of group III were significantly ameliorated when compared with the group II. Although Hedera helix administration reduced only goblet cell counts and the thicknesses of basement membrane in the asthmatic airways, dexamethasone ameliorated all histopathologic parameters except thickness of basement membrane better than Hedera helix.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Antiasmáticos/farmacología , Asma/tratamiento farmacológico , Hedera , Pulmón/efectos de los fármacos , Preparaciones de Plantas/farmacología , Administración Oral , Animales , Antiasmáticos/administración & dosificación , Asma/inmunología , Asma/patología , Membrana Basal/efectos de los fármacos , Membrana Basal/ultraestructura , Enfermedad Crónica , Dexametasona/farmacología , Modelos Animales de Enfermedad , Femenino , Células Caliciformes/efectos de los fármacos , Células Caliciformes/ultraestructura , Pulmón/inmunología , Pulmón/ultraestructura , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , Ovalbúmina , Preparaciones de Plantas/administración & dosificación , Plantas Medicinales , Factores de Tiempo
14.
J Pharm Pharmacol ; 63(12): 1587-94, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22060290

RESUMEN

OBJECTIVES: Inflammation is associated with atherosclerosis. Cholestin (Monascus purpureus-fermented rice) contains a naturally occurring statin, which has lipid-modulating, anti-inflammatory and antioxidative effects. This study aimed to investigate the effects of Cholestin extract on the expression of matrix metalloproteinase (MMP)-2 and MMP-9 by tumor necrosis factor (TNF)-α-treated human aortic smooth muscle cells (HASMCs). METHODS: Zymography, reverse transcription polymerase chain reaction and immunoblot analyses were used for analysis of MMP expression of TNF-α-stimulated HASMCs. Gel shift assay was used for analysis of transcription factor nuclear factor-κB (NF-κB) activation. Intracellular reactive oxygen species (ROS) generation was also analysed. KEY FINDINGS: The supplement of HASMCs with Cholestin extract significantly suppresses enzymatic activities of MMP-2 and MMP-9 in TNF-α-stimulated HASMCs. RT-PCR and immunoblot analyses show that Cholestin extract significantly attenuates TNF-α-induced mRNA and protein expressions of MMP-2 and MMP-9. Gel shift assays show that Cholestin treatment reduces TNF-α-activated NF-κB. Furthermore, Cholestin also attenuates intracellular ROS generation in TNF-α-treated HASMCs. The supplement with an ROS scavenger N-acetyl-cysteine (glutathione precursor) gives similar results to Cholestin. CONCLUSIONS: Cholestin reduces TNF-α-stimulated MMP-2 and MMP-9 expression as well as downregulating NF-κB activation and intracellular ROS formation in HASMCs, supporting the notion that the natural compound Cholestin may have potential application in clinical atherosclerosis disease.


Asunto(s)
Productos Biológicos/uso terapéutico , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Miocitos del Músculo Liso/enzimología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Aorta Torácica/citología , Aterosclerosis/patología , Membrana Basal/citología , Membrana Basal/efectos de los fármacos , Productos Biológicos/química , Western Blotting , Células Cultivadas , Colorantes , Ensayo de Cambio de Movilidad Electroforética , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/enzimología , Oclusión de Injerto Vascular/patología , Humanos , Miocitos del Músculo Liso/efectos de los fármacos , Reacción en Cadena de la Polimerasa , ARN/biosíntesis , ARN/genética , Especies Reactivas de Oxígeno/metabolismo , Sales de Tetrazolio , Tiazoles , Regulación hacia Arriba/efectos de los fármacos
15.
Zhongguo Zhong Yao Za Zhi ; 36(17): 2388-92, 2011 Sep.
Artículo en Chino | MEDLINE | ID: mdl-22121809

RESUMEN

OBJECTIVE: To observe the effect of salviandic acid B (SA-B) on MMP-2/9 and TIMP-2 of fibrotic cardiac tissues in rats and explore the action mechanism of SA-B anti-fibrosis of heart. METHOD: Ventricular remodeling model was induced by abdominal aortic banding (AAB) in rats. Rats were randomly divided into 6 groups: normal, model, SA-B high, SA-B middle, SA-B low and captopril control group. Histological changes of heart were observed with hemotoxylin and eosin (H&E) staining and Sirius red staining. Hydroxyproline (Hyp) content in heart tissue was measured by hydrolysis method. Expression of heart tissue collagen NIV, MMP-2/9 and TIMP-2 were analyzed with Western blot The activities of heart tissue MMP-2 were determined with gelatin zymography substrate degradation method. RESULT: SA-B treated groups had lower heart inflammation and lower heart Hyp content; decreased Collagen deposit and alleviated cardiac fibrosis. SA-B treated groups obviously decreased the expression of Collagen IV, MMP-2/9 and TIMP-2. The activity of MMP-2 was decreased in treated SA-B treated groups. CONCLUSION: The mechanism of SA-B action against cardiac fibrosis may be related to down-regulating the expression of TIMP -2 and the activity of MMP-2/9, thus protect the normal basal membrane.


Asunto(s)
Membrana Basal/enzimología , Cardiomegalia/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Animales , Membrana Basal/efectos de los fármacos , Cardiomegalia/enzimología , Cardiomegalia/genética , Modelos Animales de Enfermedad , Humanos , Masculino , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/genética , Ratas , Ratas Sprague-Dawley , Inhibidor Tisular de Metaloproteinasa-1/genética
16.
Zhongguo Zhong Yao Za Zhi ; 35(21): 2908-11, 2010 Nov.
Artículo en Chino | MEDLINE | ID: mdl-21322957

RESUMEN

OBJECTIVE: To explore the protective effects of rhubarb aglycone combined with urokinase (UK) thrombolysis on brain microvascular basement membrane impairment in rats with thrombus-occluded cerebral ischemia by regulating the expression of IgG, CoLIV and LN in rats brain, by which the level of injury of brain microvascular basement membrane could be detected. METHOD: Rats were randomly divided into sham-operated, model, thrombolysis, rhubarb aglycone and combination (rhubarb aglycone combined with thrombolysis) groups. Moreover, rats in model, thrombolysis, rhubarb aglycone and combination groups were randomly divided into 3, 6, and 9 h groups respectively. Model of thrombus-occluded cerebral ischemia was duplicated by using the combination of rats' auto-thrombus with inserting the nylon thread. Rats were administrated with thrombolysis therapy through artery at 3, 6, and 9 h after cerebral ischemia. At 24 h of administration through artery, intracranial hemorrhage ratio (ICHR) and mortality of rats were observed, and then the brain of rats was taken. In the study, expression of IgG, CoLIV and LN in rats brain were measured. RESULT: Thrombolysis at 9 h of cerebral ischemia made rats mortality and BHR increase, administration of combined therapy could make them decrease. Expression of IgG level in rats brain of 9 h and 6 h model groups increased, while CoLIV and LN expression decreased significantly. In each administration 9 h group, IgG level was lower, and CoLIV and LN were higher, such changes appeared significantly in rhubarb aglycone and association groups. CONCLUSION: Brain microvascular basement membrane impairment could be caused by the therapy of delayed thrombolysis, which made the mortality and BHR increase. Rhubarb aglycone combined with the therapy of thrombolysis could perform the protective effects on brain microvascular basement membrane and then decrease the ICHR and mortality caused by thrombolysis after cerebral ischemia.


Asunto(s)
Membrana Basal/irrigación sanguínea , Isquemia Encefálica/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Trombosis Intracraneal/tratamiento farmacológico , Rheum/química , Terapia Trombolítica , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Animales , Membrana Basal/efectos de los fármacos , Isquemia Encefálica/mortalidad , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Humanos , Trombosis Intracraneal/mortalidad , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
17.
Vet Immunol Immunopathol ; 135(3-4): 181-7, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19939463

RESUMEN

Laminitis is a local manifestation of a systemic inflammatory response that is characterized by neutrophil activation and movement of neutrophils into the laminar tissues. Given the evidence for the involvement of neutrophils in the development of laminitis, we measured concentrations of neutrophil elastase, a serine protease released from the azurophilic granules of neutrophils, in plasma, skin and laminar tissues obtained from control horses and horses given black walnut heartwood extract (BWHE) to induce laminitis. Healthy horses (5-15 years old) were randomly assigned to 4 groups: 3 experimental groups given BWHE via nasogastric tube, and a control group given an equal volume of water. The experimental groups consisted of horses euthanized 1.5h (n=5), 3h (n=6) or 12h (n=10) after BWHE administration. Control horses (n=7) were euthanized 12h after intragastric administration of water. Plasma samples were collected in all horses of the control and 12h BWHE groups at 0, 1, 2, 3, 4, 6, 8, 10, and 12h after treatment, and laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia in all 1.5 and 3h BWHE horses, in 6 of the 12h BWHE horses and in 5 of the control horses. Plasma and tissue concentrations of neutrophil elastase were determined using an equine specific ELISA, and statistical significance was set at p<0.05. Plasma concentrations of neutrophil elastase in the BWHE group were significantly higher at 6 and 8h compared to the control group and at 8 and 10h compared to time 0. Concentrations of neutrophil elastase in skin and laminar tissue were significantly higher in the 3 and 12h BWHE groups compared to the control group. Concentrations of neutrophil elastase were significantly higher in the skin than in the lamina in the 12h BWHE horses. The administration of BWHE thus results in significant increases in the concentration of neutrophil elastase in the circulation, skin and laminar tissue. These results confirm a role for neutrophils in the developmental phase of laminitis, and the systemic nature of the inflammatory process. Furthermore, neutrophil elastase may play a key role in the disintegration of the hoof basal membrane and be a target for the development of new treatments for laminitis.


Asunto(s)
Enfermedades del Pie/veterinaria , Enfermedades de los Caballos/enzimología , Caballos/metabolismo , Inflamación/veterinaria , Elastasa de Leucocito/metabolismo , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/enzimología , Modelos Animales de Enfermedad , Enfermedades del Pie/inducido químicamente , Enfermedades del Pie/enzimología , Pezuñas y Garras/efectos de los fármacos , Pezuñas y Garras/enzimología , Enfermedades de los Caballos/sangre , Enfermedades de los Caballos/inducido químicamente , Caballos/sangre , Inmunohistoquímica , Inflamación/inducido químicamente , Inflamación/enzimología , Juglans/toxicidad , Elastasa de Leucocito/sangre , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Extractos Vegetales/toxicidad , Piel/enzimología , Distribución Tisular
18.
Dev Biol ; 325(1): 94-105, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18955041

RESUMEN

Mammalian eye development requires vitamin A (retinol, ROL). The role of vitamin A at specific times during eye development was studied in rat fetuses made vitamin A deficient (VAD) after embryonic day (E) 10.5 (late VAD). The optic fissure does not close in late VAD embryos, and severe folding and collapse of the retina is observed at E18.5. Pitx2, a gene required for normal optic fissure closure, is dramatically downregulated in the periocular mesenchyme in late VAD embryos, and dissolution of the basal lamina does not occur at the optic fissure margin. The addition of ROL to late VAD embryos by E12.5 restores Pitx2 expression, supports dissolution of the basal lamina, and prevents coloboma, whereas supplementation at E13.5 does not. Surprisingly, ROL given as late as E13.5 completely prevents folding of the retina despite the presence of an open fetal fissure, showing that coloboma and retinal folding represent distinct VAD-dependent defects. Retinal folding due to VAD is preceded by an overall reduction in the percentage of cyclin D1 positive cells in the developing retina, (initially resulting in retinal thinning), as well as a dramatic reduction in the cell adhesion-related molecules, N-cadherin and beta-catenin. Reduction of retinal cell number combined with a loss of the normal cell-cell adhesion proteins may contribute to the collapse and folding of the retina that occurs in late VAD fetuses.


Asunto(s)
Retina/citología , Retina/embriología , Vitamina A/metabolismo , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/patología , Cadherinas/metabolismo , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Coloboma/complicaciones , Coloboma/embriología , Coloboma/genética , Ciclina D1/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Embrión de Mamíferos/anomalías , Embrión de Mamíferos/efectos de los fármacos , Feto/anomalías , Feto/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Retina/anomalías , Retina/efectos de los fármacos , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/efectos de los fármacos , Factores de Tiempo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Vitamina A/farmacología , Deficiencia de Vitamina A/embriología , Deficiencia de Vitamina A/genética , beta Catenina/metabolismo , Proteína del Homeodomínio PITX2
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 26 Suppl: 14-7, 2006 Jun.
Artículo en Chino | MEDLINE | ID: mdl-17569336

RESUMEN

OBJECTIVE: To study the modulation effect of Naomaitong on gelatinase system after cerebral ische-Focal cerebral I/R rat model was duplicated by method of the intralumimia/reperfusion (I/R) in rats. METHOD: nal filament technique. Rats were randomly divided into the sham-operative group, the model group, the Naomaitong group and the Nimodipine group, the latter three groups were also divided into the 3 hrs after ischemia group, and 6 hrs, 12 hrs, 24 hrs, 3 d, 6 d after IR groups. Immunohistochemical method and zymogram analysis method, etc. were adopted to observe the change of microvessel structure, gelatinase and its inhibitor expression. RESULTS: MMP-2 (IR 24 h-6 d)and MMP-9 (I/R 12 h-3 d) expression levels could be lowered and TIMP-1 expression level (IR 24 h-6 d) improved by Naomaitong. Besides, comparison of MMP-2 and MMP-9 content in zymogram analysis in each group showed that changes of its quantity were in accordance with the laws of immune expression. CONCLUSION: The protective effect of Naomaitong on cerebromicrovessel basement membrane injury in rats is related to its modulation on gelatinase system.


Asunto(s)
Isquemia Encefálica/enzimología , Medicamentos Herbarios Chinos/farmacología , Gelatinasas/metabolismo , Daño por Reperfusión/enzimología , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Modelos Animales de Enfermedad , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Medicina Tradicional China , Microvasos/efectos de los fármacos , Microvasos/metabolismo , Sustancias Protectoras/farmacología , Ratas , Inhibidor Tisular de Metaloproteinasa-1/metabolismo
20.
J Mol Neurosci ; 24(1): 167-72, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15314266

RESUMEN

In vivo amyloids consist of two classes of constituents. The first is the disease-defining protein, beta-amyloid (Abeta), in Alzheimer's disease. The second is a set of common structural components that usually are the building blocks of basement membrane (BM), a tissue structure that serves as a scaffold onto which cells normally adhere. In vitro binding interactions between one of these BM components and amyloidogenic proteins rapidly change the conformation of the amyloidogenic protein into amyloid fibrils. The offending BM component is a heparan sulfate (HS) proteoglycan, part of which is protein and the remainder a specific linear polysaccharide, which is the portion responsible for binding and imparting the typical amyloid structure to the amyloid precursor protein/peptide. Our past work has demonstrated that agents that inhibit the binding between HS and the amyloid precursor are effective antiamyloid compounds both in vitro and in vivo. Similarly, 4-deoxy analogs of glucosamine (a precursor of HS biosynthesis) are effective antiamyloid compounds both in culture and in vivo. Our continuing work concerns (1) the testing of our 4-deoxy compounds in a mouse transgenic model of Alzheimer's disease, and (2) the continuing design and synthesis of modified sugar precursors of HS, which when incorporated into the polysaccharide will alter its structure so that it affects its amyloid-inducing properties. Since our previous report, 22 additional compounds have been designed and synthesized based on the known steps involved in HS biosynthesis. Of these, 12 soluble compounds have been assessed for their effect on HS biosynthesis in hepatocyte tissue cultures. In addition, one anomer of a 4-deoxy-d-glucosamine analog, which possesses AA-amyloid inhibitory properties in vivo is in the process of being assessed for its anti-Abeta activity using a murine transgenic model of brain Abeta amyloidogenesis. The majority of the novel sugars prepared to date are analogs of N-acetylglucosamine. They have been modified at the 2-N, C-3, C-4, C-3 and C-4, or C-6 positions. One compound modified at the 2-N position (QS231), which inhibits HS synthesis in hepatocyte cultures, has shown marked enhancing properties vis-à-vis AA amyloid deposition in vivo. Very instructive results with regard to HS structure and its relation to AA amyloid deposition should be forthcoming from analyses of the AA-associated HS generated with this compound.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Glicosaminoglicanos/farmacología , Proteoglicanos de Heparán Sulfato/antagonistas & inhibidores , Fármacos Neuroprotectores/farmacología , Acetilglucosamina/análogos & derivados , Acetilglucosamina/farmacología , Acetilglucosamina/uso terapéutico , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Membrana Basal/efectos de los fármacos , Membrana Basal/metabolismo , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Glicosaminoglicanos/síntesis química , Glicosaminoglicanos/uso terapéutico , Proteoglicanos de Heparán Sulfato/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Transgénicos , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/uso terapéutico , Conformación Proteica
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