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1.
Folia Neuropathol ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-38174687

RESUMEN

Activation of the NogoA/NgR/ROCK pathway limits nerve repair after brain ischemia-reperfusion (I/R) injury. Triptolide displays anti-inflammatory, anti-oxidant, and immunosuppressive effects and is derived from the traditional Chinese medicine Tripterygium wilfordii Hook F. This agent can also penetrate the blood-brain barrier, where it has a neuroprotective effect and ameliorates cerebral I/R injury via an as yet unknown mechanism(s). Here, an animal model of middle cerebral artery occlusion and reperfusion (MCAO/R) was employed to assess triptolide's therapeutic impact on brain I/R injury and the possible mechanism of action. The results indicate that triptolide treatment can decrease cerebral infarction and nerve injury after cerebral I/R injury. Importantly, in vivo and in vitro experiments revealed that treatment with triptolide decreased NogoA, NgR, p75NTR and ROCK2 expression, and upregulated the expression of GAP43 and PSD-95, thus suggesting improved synaptic function. These results indicate that triptolide can promote nerve repair following brain I/R injury by inhibiting NogoA/NgR/ROCK signalling.

2.
Biol Trace Elem Res ; 201(7): 3381-3386, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36057764

RESUMEN

Metabolic dysfunction is a critical step in the etiopathogenesis of Alzheimer's disease. In this progressive neurological disorder, impaired zinc homeostasis has a key role that needs to be clarified. The aim of this study was to investigate the effect of zinc deficiency and administration on hippocampal Nogo-A receptor and osteocalcin gene expression in rats injected with intracerebroventricular streptozotocin (icv-STZ). Forty male Wistar rats were divided into 5 groups in equal numbers: Sham 1 group received icv artificial cerebrospinal fluid (aCSF); Sham 2 group received icv a CSF and i.p. saline; STZ group received 3 mg/kg icv STZ; STZ-Zn-deficient group received 3 mg/kg icv STZ and fed a zinc-deprived diet; STZ-Zn-supplemented group received 3 mg/kg icv STZ and i.p. zinc sulfate (5 mg/kg/day). Hippocampus tissue samples were taken following the cervical dislocation of the animals under general anesthesia. Nogo-A receptor and osteocalcin gene expression levels were determined by real-time-PCR method. Zinc supplementation attenuated the increase in hippocampal Nogo-A receptor gene expression, which was significantly increased in zinc deficiency. Again, zinc supplementation upregulated the intrinsic protective mechanisms of the brain by activating osteocalcin-expressing cells in the brain. The results of the study show that zinc has critical effects on Nogo-A receptor gene expression and hippocampal osteocalcin gene expression levels in the memory-sensitive rat hippocampus that is impaired by icv-STZ injection. These results are the first to examine the effect of zinc deficiency and supplementation on hippocampal Nogo-A receptor and osteocalcin gene expression in icv-STZ injection in rats.


Asunto(s)
Enfermedad de Alzheimer , Zinc , Ratas , Masculino , Animales , Estreptozocina/farmacología , Ratas Wistar , Proteínas Nogo/metabolismo , Proteínas Nogo/farmacología , Osteocalcina/genética , Osteocalcina/metabolismo , Zinc/farmacología , Zinc/metabolismo , Enfermedad de Alzheimer/patología , Hipocampo/metabolismo , Modelos Animales de Enfermedad , Aprendizaje por Laberinto
3.
J Ethnopharmacol ; 281: 114559, 2021 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-34461189

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Naoluoxintong (NLXT) is a traditional Chinese Medicine (TCM) prescription that is clinically used in the treatment of ischemic stroke (IS). However, its therapeutic mechanism remains unclear. AIM OF THE STUDY: To obtain the mechanism of NLXT by observing the protective effects of NLXT on the NogoA/RhoA/Rock pathway in a rat model of IS by regulating DNA methylation. MATERIALS AND METHODS: Rats were divided into five groups using a random number table: normal group, model group, NLXT group, blocker group I (NLXT + SGI-1027) and blocker group II (NLXT + Y27632). The right middle cerebral artery occlusion-reperfusion (MCAO/R) rat model was made, and the regional cerebral blood flow (rCBF) of each group was detected using laser Doppler. The methylation levels of CpG sites of neurite outgrowth inhibitor protein-A (Nogo-A), Nogo receptor (NgR), ras homolog gene family member A (RhoA) and rho-associated coiled-coil protein kinase 2 (ROCK2) genes in rat brain tissue were detected using the bisulfite method. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect NogoA, RhoA, NgR1, NgR2 and ROCK2 mRNA expression in rat brain tissue. NogoA, RhoA, NgR1, NgR2 and ROCK2 proteins were detected using immunoblotting in rat brain tissue. RESULTS: After the modeling of middle cerebral artery occlusion (MCAO), neurological deficit test was made to ensure the success of the modeling. At each time point after surgery, the rCBF of the other groups decreased compared with the normal group (P < 0.01 or P < 0.05). Meanwhile, the rCBF increased in blocker group I as well as blocker group II after 3 days (P < 0.05). There were differences in the DNA methylation sites of NogoA, RhoA, NgR and ROCK2 genes between the model group and the NLXT group (P < 0.05). Compared with the normal group, NogoA, NgR1, NgR2, RhoA and ROCK2 gene expression in the model group increased observably (P < 0.01). In comparison with the model group, NogoA and NgR1 gene expression in the blocker group II was prominently observed on the 1st day. NogoA, NgR1, NgR2, RhoA and ROCK2 gene expression remarkably reduced (P < 0.01) on the 3rd and 7th days. Compared with the normal group, NogoA, RhoA, NgR1, NgR2 and ROCK2 protein expression in the model group increased observably (P < 0.01). In comparison with the model group, NogoA, RhoA, NgR1, NgR2 and ROCK2 protein expression in the other groups declined prominently (P < 0.01). CONCLUSION: NLXT can reduce the DNA methylation level of NogoA pathway after IS, thus inhibit the expression of NogoA/RhoA/ROCK pathway from producing anti-cerebral ischemia pharmacological effect.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Proteínas Nogo/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Quinasas Asociadas a rho/metabolismo , Animales , ADN/metabolismo , Metilación de ADN , Regulación de la Expresión Génica/efectos de los fármacos , Infarto de la Arteria Cerebral Media , Masculino , Fármacos Neuroprotectores/farmacología , Proteínas Nogo/genética , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Proteínas de Unión al GTP rho/genética , Quinasas Asociadas a rho/genética
4.
J Ethnopharmacol ; 272: 113943, 2021 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-33617967

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Xuesaitong (XST) is a traditional Chinese medicine injection with neuroprotective properties and has been extensively used to treat stroke for many years. The main component of XST is Panax notoginseng saponins (PNS), which is the main extract of the Chinese herbal medicine Panax notoginseng. AIM OF THE STUDY: In this study, we investigated whether XST provided long-term neuroprotection by inhibiting neurite outgrowth inhibitor-A (Nogo-A) and the ROCKII pathway in experimental rats after middle cerebral artery occlusion (MCAO) and in SH-SY5Y cells exposed to oxygen-glucose deprivation/reperfusion (OGD/R). MATERIALS AND METHODS: Rats with permanent MCAO were administered XST, Y27632, XST plus Y27632, and nimodipine for 14 and 28 days. Successful MCAO onset was confirmed by 2,3,5-triphenyl tetrazolium chloride (TTC) staining. Neurological deficit score (NDS) was used to assess neurological impairment. Hematoxylin-eosin (HE) staining and immunohistochemical (IHC) analysis of synaptophysin (SYN) and postsynaptic density protein-95 (PSD-95) were performed to evaluate cerebral ischemic injury and the neuroprotective capability of XST. Nogo-A levels and the ROCKII pathway were detected by IHC analysis, western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR) to explore the protective mechanism of XST. OGD/R model was established in SH-SY5Y cells. Cell counting kit 8 (CCK8) was applied to detect the optimum OGD time and XST concentration. The expression levels Nogo-A and ROCKII pathway were determined using western blotting. RESULTS: Our results showed that XST reduced neurological dysfunction and pathological damage, promoted weight gain and synaptic regeneration, reduced Nogo-A mRNA and protein levels, and inhibited the ROCKII pathway in MCAO rats. CCK8 assay displayed that the optimal OGD time and optimal XST concentration were 7 h and 20 µg/mL respectively in SH-SY5Y cells. XST could evidently inhibit OGD/R-induced Nogo-A protein expression and ROCKII pathway activation in SH-SY5Y cells. CONCLUSIONS: The present study suggested that XST exerted long-term neuroprotective effects that assisted in stroke recovery, possibly through inhibition of the ROCKII pathway.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Saponinas/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Homólogo 4 de la Proteína Discs Large/metabolismo , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Masculino , Neuroprotección/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Proteínas Nogo/antagonistas & inhibidores , Proteínas Nogo/genética , Proteínas Nogo/metabolismo , Panax notoginseng/química , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Saponinas/uso terapéutico , Transducción de Señal/efectos de los fármacos , Accidente Cerebrovascular/tratamiento farmacológico , Sinaptofisina/metabolismo , Factores de Tiempo , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismo
5.
Neuroscience ; 431: 103-114, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32068082

RESUMEN

Focal cerebral infarction leads to autophagic activation, which contributes to secondary neuronal damage in the ipsilateral thalamus. Although Nogo-A deactivation enhances neuronal plasticity, its role in autophagic activation in the thalamus after ischemic stroke remains unclear. This study aimed to investigate the potential roles of Nogo-A/Nogo-66 receptor 1 (NgR1) in autophagic activation in the ipsilateral thalamus after cerebral infarction. Focal neocortical infarction was established using the middle cerebral artery occlusion (MCAO) method. Secondary damage in the ipsilateral thalamus was assessed by Nissl staining and immunostaining. The expression of Nogo-A, NgR1, Rho-A and Rho-associated coiled-coil containing protein kinase 1 (ROCK1) as well as autophagic flux were evaluated by immunofluorescence and immunoblotting. The roles of Nogo-A-NgR1 signaling in autophagic activation were determined by intraventricular delivery of an NgR1 antagonist peptide, NEP1-40, at 24 h after MCAO. The results showed that Nogo-A and NgR1 overexpression temporally coincided with marked increases in the levels of Beclin1, LC3-II and sequestosome 1 (SQSTM1)/p62 in the ipsilateral thalamus at seven and fourteen days after MCAO. In contrast, NEP1-40 treatment significantly reduced the expression of Rho-A and ROCK1 which was accompanied by marked reductions of LC3-II conversion as well as the levels of Beclin1 and SQSTM1/p62. Furthermore, NEP1-40 treatment significantly reduced neuronal loss and gliosis in the ipsilateral thalamus, and accelerated somatosensory recovery at the observed time-points after MCAO. These results suggest that blockade of Nogo-A-NgR1 signaling inhibits autophagic activation, attenuates secondary neuronal damage in the ipsilateral thalamus, and promotes functional recovery after focal cerebral cortical infarction.


Asunto(s)
Neuronas , Tálamo , Animales , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Proteínas Nogo , Receptor Nogo 1 , Ratas , Ratas Sprague-Dawley
6.
Artículo en Chino | WPRIM | ID: wpr-923910

RESUMEN

@#Objective To investigate the effects of Tuina of Three Handing-Three Points on hindlimb motor function and expression of protein NogoA and its receptor NgR in the spinal cord of rats with sciatic nerve injury. Methods A total of 64 male Sprague-Dawley rats were randomly assigned to normal group (n = 16), sham group (n = 16), model group (n = 16) and Tuina group (n = 16). The model group and Tuina group prepared the sciatic nerve injury model with brace method. Tuina group received Tuina in methods of pressing, strumming and circular rubbing on Yinmen (BL37), Chengshan (BL57) and Yanglingquan (GB34) with Tuina manipulation emulator. The rats were assessed with oblique plate test seven days after operation and 20 days after Tuina. Then, the spinal cord tissues were extracted to detect the expression of protein of NogoA and NgR with Western blotting. Results The scores of the oblique plate test decreased in the model group and Tuina group seven days after operation compared with those in the normal group (P < 0.05), while the expression NgR increased (P < 0.05). The scores of the oblique plate test increased in Tuina group compared with those in the model group 20 days after Tuina (P < 0.05), while the expression of NgR decreased (P < 0.05), similar to the normal group (P > 0.05). Conclusion Tuina of Three Handing-Three Points can improve the hindlimb motor function in rats with sciatic nerve injury, which may be related to inhibition of the expression of NgR in the spinal cord after sciatic nerve injury.

7.
Artículo en Chino | WPRIM | ID: wpr-702524

RESUMEN

Objective To investigate the phased expression of gene and protein of NogoA and its receptor (NgR) that affects axon growth of spinal cord injury (SCI), and to explore the time window effect of electroacupuncture on SCI rats. Methods A total of 144 female Sprague-Dawley rats were randomly assigned to sham operation group (group A, n=48) and model group (n=96). In the model group, Allen's method was used to establish SCI rats model, and they were further subdivided into model control group (group B, n=48) and electroacupuncture group (group C, n=48). Group C received electroacupuncture on Dazhui (GV14), Yaoyangguan (GV3), bilateral Ciliao (BL32) and Zu-sanli (ST36) with loose-tight wave, for 20 minutes every day, one day, seven days and 14 days after modeling. The rats at every interventional therapy time were randomly subdivided into two subgroups, which accepted sev-en or 14 days of treatment. Groups A and B were killed and the injured spinal cord tissue was extracted one day, three days, seven days, 14 days and 28 days after modeling, group C at the corresponding time. The hind limb motor function was assessed with BBB score before all of rats were killed. Four samples at every time in each group were randomly selected to detect the expression of mRNA and protein of NogoA and NgR at different stage of SCI using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Results The BBB score began to increase 14 days after modeling, and significantly increased until 28 days after model-ing (P<0.05), compared with one day, three days and seven days after modeling in group B. The BBB score in-creased in group C than in group B at all the time points (P<0.05), except 14 days after electroacupuncture one day after modeling. The BBB score was higher as electroacupuncture intervening seven days and 14 days after modeling than that at one day after modeling in group C, and no significant difference was found between seven days and 14 days of treatment at either electroacupuncture time point (P>0.05). The expression of gene and pro-tein of NogoA and NgR in group B was in the increasing tendency after SCI, and was at the peak until 21 days af-ter modeling, and was higher in group B than in group A at each time point (P<0.01). The expression of gene and protein of NogoA decreased at all the time points in group C than in group B (P<0.05), except seven days of elec-troacupuncture intervening one day after modeling in the expression of NogoA mRNA (P>0.05). The expression of gene and protein of NogoA and NgR was lower as electroacupuncture intervening 14 days after modeling than one day after modeling in group C (P<0.05). There was no significant difference in the expression of gene and protein of NogoA and NgR between electroacupuncture intervening 14 days and seven days after modeling, and seven days and one day after modeling (P>0.05); as well as between seven days and 14 days of treatment at each time point (P>0.05). Conclusion Elerctroacupuncture could improve the hind limb motor function, which may associate with the inhibition of the expression of gene and protein of NogoA and NgR in injured spinal cord of rats after SCI. Elerctroacu-puncture is effective in the treatment of SCI at the early time, however, it is much better in the recovery stage.

8.
Exp Ther Med ; 14(2): 905-912, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28810542

RESUMEN

The purpose of the present study was to evaluate the effect of electroacupuncture (EA) on the axonal regeneration environment following cerebral ischemia injury and to investigate whether it was associated with Nogo-A/Nogo receptor (NgR)/RhoA/Rho-associated protein kinase (ROCK) signaling. Using a rat model of focal cerebral ischemia, the effects of EA at the Quchi (LI11) and Zusanli (ST36) acupoints on axonal growth inhibitory protein and axonal growth factors were assessed and the underlying molecular mechanisms were investigated. It was found that EA at the Quchi and Zusanli acupoints significantly improved neurological deficit scores following ischemia (P<0.05), and reduced the cerebral infarct volume. Moreover, it was demonstrated that crucial signaling molecules in the Nogo-A signaling pathway were regulated by EA. These results suggest that EA provides a less inhibitory environment for axonal regeneration following cerebral ischemia through inhibition of Nogo-A/NgR/RhoA/ROCK signaling.

9.
BMC Complement Altern Med ; 17(1): 346, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28668079

RESUMEN

BACKGROUND: Axon growth inhibitory factors NogoA/Nogo receptor (NgR) and its signaling pathways RhoA/Rho kinase (ROCK) play a critical role in the repair of nerve damage in multiple sclerosis (MS). Bu Shen Yi Sui Capsule (BSYSC) is an effective Chinese formula utilized to treat MS in clinical setting and noted for its potent neuroprotective effects. In this study, we focus on the effects of BSYSC on promoting nerve repair and the underlying mechanisms in mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS. METHODS: The EAE mouse model was induced by injecting subcutaneously with myelin oligodendrocyte glycoprotein (MOG) 35-55 supplemented with pertussis toxin. BSYSC was orally administrated at dose of 3.0 g/kg once a day for 40 days. The levels of protein gene product (PGP) 9.5, p-Tau, growth associated protein (GAP) -43, KI67 and Nestin in the brain or spinal cord on 20 and 40 day post-induction (dpi) were detected via immunofluorescence and Western blot analysis. Furthermore, NogoA/NgR and RhoA/ROCK signaling molecules were studied by qRT-PCR and Western blot analysis. RESULTS: Twenty or 40 days of treatment with BSYSC increased markedly PGP9.5 and GAP-43 levels, reduced p-Tau in the brain or spinal cord of mice with EAE. In addition, BSYSC elevated significantly the expression of KI67 and Nestin in the spinal cord 40 dpi. Further study showed that the activation of NogoA/NgR and RhoA/ROCK were suppressed by the presence of BSYSC. CONCLUSIONS: BSYSC could attenuate axonal injury and promote repair of axonal damage in EAE mice in part through the down-regulation of NogoA/NgR and RhoA/ROCK signaling pathways.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Proteínas Nogo/metabolismo , Receptores Nogo/metabolismo , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Proteínas Nogo/genética , Receptores Nogo/genética , Transducción de Señal , Quinasas Asociadas a rho/genética , Proteína de Unión al GTP rhoA/genética
10.
Mol Neurobiol ; 54(10): 8404-8418, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27933584

RESUMEN

Myelin-associated inhibitors, such as NogoA, myelin-associated glycoprotein (MAG), and oligodendrocyte myelin glycoprotein (OMgp), play a pivotal role in the lack of neuroregeneration in multiple sclerosis, an inflammatory demyelinating disease of the central nervous system (CNS). Matrine (MAT), a monomer that is used in traditional Chinese medicine as an anti-inflammatory agent, has shown beneficial effects in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. However, the underlying mechanisms of MAT-induced EAE amelioration are not fully understood. In the present study, we show that MAT treatment suppressed ongoing EAE, and this effect correlated with an increased expression of growth-associated protein 43, an established marker for axonal regeneration. MAT treatment significantly reduced the levels of NogoA, its receptor complex NgR/p75NTR/LINGO-1, and their downstream RhoA/ROCK signaling pathway in the CNS. In contrast, intracellular cyclic AMP (cAMP) levels and its protein kinase (protein kinase A (PKA)), which can promote axonal regrowth by inactivating the RhoA, were upregulated. Importantly, adding MAT in primary astrocytes in vitro largely induced cAMP/PKA expression, and blockade of cAMP significantly diminished MAT-induced expression of PKA and production of BDNF, a potent neurotrophic factor for neuroregeneration. Taken together, our findings demonstrate that the beneficial effects of MAT on EAE can be attributed not only to its capacity for immunomodulation, but also to its directly promoting regeneration of the injured CNS.


Asunto(s)
Alcaloides/uso terapéutico , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/metabolismo , Inhibición Neural/fisiología , Proteínas Nogo/metabolismo , Quinolizinas/uso terapéutico , Transducción de Señal/fisiología , Alcaloides/farmacología , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Células Cultivadas , Femenino , Cobayas , Ratones , Inhibición Neural/efectos de los fármacos , Proteínas Nogo/antagonistas & inhibidores , Quinolizinas/farmacología , Distribución Aleatoria , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento , Matrinas
11.
Neural Regen Res ; 10(10): 1628-34, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26692861

RESUMEN

Previous studies have shown that the neurite growth inhibitor Nogo-A can cause secondary neural damage by activating RhoA. In the present study, we hypothesized that electroacupuncture promotes neurological functional recovery after spinal cord injury by inhibiting RhoA expression. We established a rat model of acute spinal cord injury using a modification of Allen's method. The rats were given electroacupuncture treatment at Dazhui (Du14), Mingmen (Du4), Sanyinjiao (SP6), Huantiao (GB30), Zusanli (ST36) and Kunlun (BL60) acupoints with a sparse-dense wave at a frequency of 4 Hz for 30 minutes, once a day, for a total of 7 days. Seven days after injury, the Basso, Beattie and Bresnahan (BBB) locomotor scale and inclined plane test scores were significantly increased, the number of apoptotic cells in the spinal cord tissue was significantly reduced, and RhoA and Nogo-A mRNA and protein expression levels were decreased in rats given electroacupuncture compared with rats not given electroacupuncture. Four weeks after injury, pathological tissue damage in the spinal cord at the site of injury was alleviated, the numbers of glial fibrillary acidic protein- and neurofilament 200-positive fibers were increased, the latencies of somatosensory-evoked and motor-evoked potentials were shortened, and their amplitudes were increased in rats given electroacupuncture. These findings suggest that electroacupuncture treatment reduces neuronal apoptosis and decreases RhoA and Nogo-A mRNA and protein expression at the site of spinal cord injury, thereby promoting tissue repair and neurological functional recovery.

12.
J Neurochem ; 132(1): 70-84, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25314656

RESUMEN

Axonal regeneration after injury to the CNS is hampered by myelin-derived inhibitors, such as Nogo-A. Natural products, such as green tea, which are neuroprotective and safe for long-term therapy, would complement ongoing various pharmacological approaches. In this study, using nerve growth factor-differentiated neuronal-like Neuroscreen-1 cells, we show that extremely low concentrations of unfractionated green tea polyphenol mixture (GTPP) and its active ingredient, epigallocatechin-3-gallate (EGCG), prevent both the neurite outgrowth-inhibiting activity and growth cone-collapsing activity of Nogo-66 (C-terminal domain of Nogo-A). Furthermore, a synergistic interaction was observed among GTPP constituents. This preventive effect was dependent on 67-kDa laminin receptor (67LR) to which EGCG binds with high affinity. The antioxidants N-acetylcysteine and cell-permeable catalase abolished this preventive effect of GTPP and EGCG, suggesting the involvement of sublethal levels of H2 O2 in this process. Accordingly, exogenous sublethal concentrations of H2 O2 , added as a bolus dose (5 µM) or more effectively through a steady-state generation (1-2 µM), mimicked GTPP in counteracting the action of Nogo-66. Exogenous H2 O2 mediated this action by bypassing the requirement of 67LR. Taken together, these results show for the first time that GTPP and EGCG, acting through 67LR and elevating intracellular sublethal levels of H2 O2 , inhibit the antineuritogenic action of Nogo-A. Currently, several agents are being evaluated for overcoming axonal growth inhibitors to promote functional recovery after stroke and spinal cord injury. Epigallocatechin-3-gallate (EGCG), present in green tea polyphenol mixture (GTPP), prevents antineuritogenic activity of Nogo-A, a myelin-derived axonal growth inhibitor. The preventive action of EGCG involves the cell-surface-associated 67-kDa laminin receptor and H2 O2 . GTPP may complement ongoing efforts to treat neuronal injuries.>


Asunto(s)
Peróxido de Hidrógeno/farmacología , Proteínas de la Mielina/antagonistas & inhibidores , Proteínas de la Mielina/farmacología , Neuritas/efectos de los fármacos , Oxidantes/farmacología , Polifenoles/farmacología , Receptores de Laminina/efectos de los fármacos , Té/química , Animales , Células Cultivadas , Conos de Crecimiento/efectos de los fármacos , Ratones , Proteínas Nogo , Polifenoles/química , Seudópodos/efectos de los fármacos
13.
J Ethnopharmacol ; 158 Pt A: 102-12, 2014 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-25448504

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Zuo-Gui pills (ZGPs) and You-Gui pills (YGPs) are 2 traditional Chinese herbal formulas used for treating multiple sclerosis (MS) in the clinical setting and have been shown to have neuroprotective effects in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. The aim of this study was to explore the mechanisms underlying the neuroprotective functions of ZGPs and YGPs. MATERIALS AND METHODS: Female Lewis rats were randomly divided into normal control, EAE model, 2g/kg ZGP-treated EAE, 3g/kg YGP-treated EAE, and prednisone acetate-treated groups. EAE model was induced by subcutaneous injection of MBP68-86 antigen. The neurological function scores were estimated. Histological structures of the brains and spinal cords were observed, and myelinated and axons imaged. NogoA, Nogo receptor (NgR), and RhoA transcript and protein levels were measured by real-time quantitative RT-PCR and western blotting on postimmunization (PI) days 14 (acute stage) and 28 (remission stage). RESULTS: ZGPs and YGPs significantly reduced neurological functions scores and abrogated inflammatory infiltrates, demyelination, and axonal damage. Furthermore, treatment with ZGPs and YGPs inhibited NogoA, NgR, and RhoA mRNA and protein expression in rats at both the acute and remission stages. ZGPs exhibited stronger effects on NogoA and RhoA expressions, as well as neurological function, during the acute stage of EAE, while YGPs caused greater reductions in NogoA expression during the remission stage. CONCLUSIONS: Our findings suggested that ZGPs and YGPs exerted neuroprotective effects by downregulation of NogoA, NgR, and RhoA pathways, with differences in response times and targets observed between ZGPs and YGPs.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/fisiopatología , Femenino , Proteínas Ligadas a GPI/genética , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/fisiopatología , Proteínas de la Mielina/genética , Proteínas Nogo , Receptor Nogo 1 , Ratas , Ratas Endogámicas Lew , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Superficie Celular/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Proteína de Unión al GTP rhoA/genética
14.
Artículo en Chino | WPRIM | ID: wpr-860513

RESUMEN

OBJECTIVE: To study the effect of Chinese herb Suifukang on the expression of Nogo protein-A in the brain of MCAO rats and explore the action mechanism of its promoting neurogenesis. METHODS: SD rats were selected and randomized into six groups: normal group, control group, treatment group of methylprednisolone, treatment group of Chinese herb Suifukang in large-does, middle-does and small-does. The models of MCAO rats were successfully established by the method of Koizumi. After the surgery, the rats of drug group had been taken orally Suifukang by 10 g · kg-1 crude drug one time daily, and the rest groups had been taken orally equivalence saline once a day. The brain of rats were investigated and the expression of NoGo-A was detected by immunohistology method and RT-PCR method. RESULTS: The expression of NoGo-A in the injured brain was apparently inhibited by Suifukang (P < 0.01). CONCLUSION: Suifukang can inhibit the expression of NoGo-A. So this function may be one of the mechanisms that Suifukang can promote the functional recovery after brain injury. Copyright 2013 by the Chinese Pharmaceutical Association.

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