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BACKGROUND: Emerging evidence suggests that the spread of glioma to the subventricular zone (SVZ) is closely related to glioma recurrence and patient survival. Neural stem cells (NSCs) are the main cell type in the SVZ region and exhibit tumor-homing ability. AIM: To evaluate the effects of conditioned medium (CM) derived from SVZ NSCs on the cancer-related behaviors of glioma cells. METHODS: The characteristics of SVZ hNSCs were identified by immunofluorescence. The normoxic-hNSC-CM and hypoxic-hNSC-CM (3% O2, oxygen-glucose deprived [OGD] culturing) were collected from 80%-90% confluent SVZ NSCs in sterile conditions. The CCK8 and Transwell assays were used to compare and evaluate the effects of normoxic-CM and hypoxic-CM on glioma proliferation and invasion. Then proteins secreted from SVZ NSCs into the CM were investigated by mass spectrometry, and the potential effects of candidate protein NCAN in the regulation of glioma progression were examined by CCK8 and Transwell assays. RESULTS: The CM from SVZ NSCs significantly increased the proliferation and invasion of glioma cells, particularly the CM from OGD NSCs induced under hypoxic conditions. Furthermore, the secreted protein neurocan (NCAN) in CM from OGD NSCs was identified by proteomic analysis. NCAN was expressed in glioma cells and played regulatory roles in mediating the progression of glioma cells mainly via the Rho/Rho-associated protein kinase pathway. CONCLUSION: Our study identified a potential interactive mechanism between SVZ NSCs and glioma cells, in which SVZ NSCs promote glioma progression via the secreted protein NCAN. These findings suggested that exploring the CM derived from cells could be a novel strategy for optimizing treatments and that NCAN derived from SVZ NSCs may be a potential new target in glioma progression.
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Evidence increasingly suggests that type 2 diabetes mellitus (T2DM) is a risk factor for neurodegenerative diseases (NDDs), such as Alzheimer's disease (AD) and Parkinson's disease (PD). These diseases share many pathological processes, including oxidative stress, local inflammation/neuroinflammation and chronic, low-grade (systemic) inflammation, which are exacerbated by aging, a common risk factor for T2DM and NDDs. Here, we focus on the link between chronic inflammation driven by peripheral metabolic disease and how this may impact neurodegeneration in AD and PD. We review the relationship between these common pathological processes in AD and PD from the perspective of the "pro-inflammatory" signaling of the nucleotide-binding oligomerization domain (NOD)-, leucine-rich repeat- (LRR)-, and pyrin domain-containing protein 3 (NLRP3) inflammasome complex. Since the need for effective disease-modifying therapies in T2DM, AD and PD is significant, the relationship between these diseases is important as a positive clinical impact on one may benefit the others. We briefly consider how novel strategies may target neuro-inflammation and provide potential therapies for AD and PD.
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Enfermedad de Alzheimer , Diabetes Mellitus Tipo 2 , Inflamasomas , Inflamación , Interleucina-18 , Interleucina-1beta , Proteína con Dominio Pirina 3 de la Familia NLR , Enfermedad de Parkinson , Enfermedad de Alzheimer/inmunología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Diabetes Mellitus Tipo 2/inmunología , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Inflamasomas/inmunología , Inflamasomas/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Interleucina-18/inmunología , Interleucina-18/metabolismo , Interleucina-1beta/inmunología , Interleucina-1beta/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad de Parkinson/inmunología , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patologíaRESUMEN
Female infertility is when a woman of reproductive age and sexual active, without contraception, cannot get pregnant after a year and more or keeps having miscarriages. Although conventional treatments for infertility such as hormone therapy, in vitro fertilization and many more, helped many female patients with infertility get pregnant during past a few decades, it is far from satisfactory with prolonging treatment time frames and emotional and financial burden. In recent years, more patients with infertile problems are seeking to alternative and complementary medicines to achieve a better outcome. In particular, Chinese herbal medicine (CHM) is increasingly popular for treating infertility due to its effectiveness and complimentary with conventional treatments. However, the mechanisms of action of CHM in treating female infertility are not well understood. In this chapter authors reviewed research development of CHM applied in many infertile models and CHM clinical studies in many conditions associated with female infertility, published in past 15 years. The data of review showed that CHM has either specific target mechanisms of action or multitarget mechanisms of action, via regulating relevant hormone levels in female reproductive system, improving ovary function, enhancing uterine receptivity. More studies are warranted to explore the new drugs from CHM and ensure safety, efficacy, and consistency of CHM.
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Medicamentos Herbarios Chinos/uso terapéutico , Infertilidad Femenina/terapia , Animales , Medicamentos Herbarios Chinos/farmacología , Femenino , Genitales/efectos de los fármacos , Humanos , Infertilidad Femenina/fisiopatología , Ovario/efectos de los fármacos , Micción/efectos de los fármacosRESUMEN
Male infertility normally refers a male's inability to cause pregnancy in a fertile female partner after 1 year of unprotected intercourse. Male infertility in recent years has been attracting increasing interest from public due to the evidence in decline in semen quality. There are many factors contributing to the male infertility including abnormal spermatogenesis; reproductive tract anomalies or obstruction; inadequate sexual and ejaculatory functions; and impaired sperm motility, imbalance in hormone levels, and immune system dysfunction. Although conventional treatments such as medication, surgical operation, and advanced techniques have helped many male with infertility cause pregnancy in their female partners, effectiveness is not satisfactory and associated with adverse effects. Chinese herbal medicine (CHM) has been used to improve male infertility in China for a very long time and has now been increasingly popular in Western countries for treating infertility. In this chapter we summarized recent development in basic research and clinical studies of CHM in treating male infertility. It has showed that CHM improved sperm motility and quality, increased sperm count and rebalanced inadequate hormone levels, and adjusted immune functions leading to the increased number of fertility. Further, CHM in combination with conventional therapies improved efficacy of conventional treatments. More studies are needed to indentify the new drugs from CHM and ensure safety, efficacy, and consistency of CHM.
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Medicamentos Herbarios Chinos/uso terapéutico , Infertilidad Masculina/terapia , Medicina Tradicional China/métodos , Animales , Humanos , MasculinoRESUMEN
Parkinson's disease is a progressive neurodegenerative disorder. Although both genetic and environmental factors are implicated in the development of Parkinson's disease, the cause of the disease is still unclear. So far conventional treatments to Parkinson's are symptomatic relief and focused mainly on motor symptoms. Chinese herbal medicine has been used to treat many conditions in China, Korea, Japan, and many Southeast Asian countries for 1000 years. During past a few decades, Chinese herbal medicine has gained wider and increasing acceptance within both public and medical profession due to its effectiveness on many conditions in western countries. In this chapter, mechanisms of action of many Chinese herbal compounds/extracts and Chinese herb formulas on the models of Parkinson's were reviewed. Further, reports of effectiveness of Chinese herb formulas on patients with Parkinson's were summarized. It was shown that both Chinese herbal compounds/extracts and herb formulas have either specific target mechanisms of action or multitargets mechanisms of action, as antioxidant, antiinflammatory, and antiapoptosis agents. Clinical studies showed that Chinese herb formulas as an adjunct improved both motor and nonmotor symptoms, and reduced dose of dopaminergic drugs and occurrence of dyskinesia. The evidence from the studies suggests that Chinese herb medicine has potential, acting as neuroprotective to slow down the progression of Parkinson's, and it is able to simultaneously treat both motor and nonmotor symptoms of Parkinson's. More studies are needed to explore the new compounds/extracts derived from Chinese herbs, in particular, their mechanisms of action. It is hopeful that new drugs developed from Chinese herb compounds/extracts and Chinese herb formulas will lead to better and complimentary therapy to PD.
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Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China , Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/terapia , Animales , Medicamentos Herbarios Chinos/química , HumanosRESUMEN
Parkinson's disease is a neurodegenerative disorder. Parkinson's clinical feature is characterized by its motor manifestations, although its many nonmotor symptoms occur earlier and have more profound impact on the quality of patient's life. Acupuncture has been increasingly popular and has been used to treat patients with Parkinson's. In this article, we have studied the clinical reports of acupuncture treatment for Parkinson's, which were listed in Medline, PubMed, EMBASE, CNKI, and CINAHL databases in the past 15 years. It was found that acupuncture either manual or electroacupuncture stimulation at specific acupoints relieved some motor symptoms in patients with Parkinson's and markedly improved many nonmotor symptoms such as psychiatric disorders, sleep problems, and gastrointestinal symptoms. When it was used as an adjunct for levodopa, acupuncture improved therapeutic efficacy and reduced dosage and the occurrence of side effects of levodopa. However, the results were constrained by small sample sizes, methodological flaws, and blinding methods of studies. Although the evidence for the effectiveness of acupuncture for treating Parkinson's is inconclusive, therapeutic potential of acupuncture seems quite promising. More studies, either comparative effectiveness research or high-quality placebo-controlled clinical studies are warranted.
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Terapia por Acupuntura/métodos , Enfermedades Gastrointestinales/terapia , Trastornos Mentales/terapia , Enfermedad de Parkinson/terapia , Trastornos del Sueño-Vigilia/terapia , Animales , Bases de Datos Bibliográficas/estadística & datos numéricos , Enfermedades Gastrointestinales/etiología , Humanos , Trastornos Mentales/etiología , Enfermedad de Parkinson/complicaciones , Trastornos del Sueño-Vigilia/etiologíaRESUMEN
The treatment of dyskinesia in Parkinson׳s disease remains poor but H3 receptor agonists have been suggested as a novel pharmacological approach. We examined the effects of the H3 agonist, immepip, in 6-OHDA-lesioned rats exhibiting AIMs (abnormal involuntary movements), a rat analogue of dyskinesia, in response to l-dopa compared to the known anti-dyskinetic agents amantadine, MK-801 and 8-OHDPAT. We then attempted to extend these studies in to dyskinetic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treated common marmosets. Amantadine, MK-801 and 8-OHDPAT all dose-dependently reduced l-dopa-induced axial, lingual and oral (ALO) AIMs in 6-OHDA-lesioned animals accompanied by a reduction in contralateral rotation with higher doses of amantadine and MK-801. By contrast, immepip had no effect on AIMs expression or contralateral rotation. In the MPTP-treated common marmoset exhibiting dyskinesia to l-dopa, immepip alone induced retching and in combination with l-dopa administered subcutaneously or orally induced the rapid onset of retching and vomiting which was not controlled by pretreatment with domperidone. Administration of the unrelated H3 agonist, imetit had the same effect. Despite causing negative side-effects, it appears that both agonists reduced the antiparkinsonian response to l-dopa resulting in reduced dyskinesia. H3 agonists appear unlikely candidates for the treatment of dyskinesia in PD based on lack of evidence of efficacy and potential adverse effects.
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Discinesia Inducida por Medicamentos/tratamiento farmacológico , Discinesias/tratamiento farmacológico , Agonistas de los Receptores Histamínicos/uso terapéutico , Imidazoles/uso terapéutico , Levodopa/toxicidad , Oxidopamina/toxicidad , Piperidinas/uso terapéutico , Animales , Discinesia Inducida por Medicamentos/fisiopatología , Discinesias/fisiopatología , Masculino , Ratas , Ratas WistarRESUMEN
The acupuncture has been practiced in China for more than 3000 years and was spread to Europe and American from the sixteenth to the nineteenth century. The history of acupuncture research was initiated in the eighteenth century and developed rapidly since then. In the past, physicians tried hard to apply acupuncture into clinical practice, while scientists were focused on the possible characteristics of acupoints and meridians. In the modern time, scientists have strived hard to evaluate the real effectiveness of acupuncture and the underlying physiological and biological mechanisms of acupuncture. Reviewing research history from past to present, we are delighted to witness this wonderful development. Accumulated evidences that acupuncture is beneficial in various conditions significantly enhanced our understanding the mechanisms of acupuncture treatment. However, there is still no conclusive evidence in acupuncture clinical studies. The clinical research still needs great improving, while the basic research results need to be appropriately transformed into clinical outcomes. Based on current achievements, we believe that although the challenges and difficulties exist, a more collaborative, innovative, and integrated approach will help us to achieve further progress in future acupuncture research.
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Terapia por Acupuntura/historia , Acupuntura/historia , Investigación Biomédica/historia , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , HumanosRESUMEN
Acupuncture, as a modality treatment, has gained increasing popularity and acceptance between public and health-care professionals worldwide. Recently, there has been intensive debate about the efficacy of acupuncture therapy due to the conflicting outcome of clinical trials. Acupoint specificity was regarded as one of the core scientific issues with respect to acupuncture practice at the Society for Acupuncture Research international symposium held in 2007. In this chapter, we reviewed the recent development in basic science and clinical studies on the role of acupoint specificity. The evidence cumulated from brain imaging and many biological studies showed that the point specificity in acupuncture does exist, although acupoint specificity-related issues such as sham acupoint and placebo phenomenon need to be seriously considered. How to optimize the efficacy of acupoint and minimize the impact of sham acupuncture is an urgent issue faced by acupuncture community, and more studies are warranted on the subjects.
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Puntos de Acupuntura , Terapia por Acupuntura/normas , Encéfalo/fisiología , HumanosRESUMEN
Acupuncture has been used to treat different conditions for at least 3000 years in China and has gained increasing acceptance worldwide. The acupuncture needle inserted into the muscle layer at the acupoint produces the so-called obtaining qi sensation that causes the excitation of A-δ and C-fibers of the muscle tissue, resulting in afferent signals. The afferent signals pass through the dorsal horn cells of the spinal cord ascending to the brain, such as the hypothalamus, enhancing the release of neuropeptides and hormones, and these afferent signals in the spinal segment may innervate the visceral organ, inducing effect on visceral function. Here, we reviewed the effect of acupuncture stimulation on neuropeptides and hormones, including ß-endorphin, serotonin, oxytocin, adrenocorticotropic hormone, gonadotropin-releasing hormone, corticotrophin-releasing hormone, cholecystokinin, and acetylcholine, as well as insulin sensitivity, immunomodulation (anti-inflammation), and autonomic nerve activity.
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Terapia por Acupuntura , Encéfalo/metabolismo , Sistemas Neurosecretores/fisiología , Animales , Humanos , Sistema Hipotálamo-Hipofisario/metabolismo , Neuropéptidos/fisiología , Sistema Hipófiso-Suprarrenal/metabolismoRESUMEN
Parkinson's disease is an age-related progressive neurodegenerative disease. The etiology and pathogenetic mechanisms that cause PD are still not fully understood. The available treatments to PD are only symptomatic relief. Acupuncture is used to treat many medical conditions for 1000 years in China and has gained wider and increasing acceptance within both public and medical profession because it has been a very safe and well-tolerated treatment. In this chapter, we reviewed relevant laboratory findings regarding acupuncture mechanism on Parkinson's. We showed that acupuncture stimulation in Parkinson's models had generated valuable mechanistic insight of Parkinson's and showed that acupuncture treatment is in fact a neuroprotective therapy that increase the release of various neuroprotective agents such as brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and cyclophilin A. In addition, acupuncture therapy slows cell death process and attenuates oxidative stress to dopaminergic neurons in the substantia nigra. Further, acupuncture therapy modulates neuronal activity of the basal ganglia output structures. These results suggest that early application of acupuncture therapy to Parkinson's patients may be helpful for the best efficacy of acupuncture treatment. It is hopeful that translation of achievement in acupuncture research in Parkinson's models will maximize the potentials of acupuncture treatment.
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Terapia por Acupuntura/tendencias , Enfermedad de Parkinson/terapia , Investigación Biomédica , Encéfalo/metabolismo , Encéfalo/patología , HumanosRESUMEN
Alzheimer's disease is the most common form of dementia diagnosed in the aging population worldwide. The cause of Alzheimer's is still not clear. There is no cure for the disease and current treatments are only symptomatic relieve. The search for new treatment is made ever more urgent due to increasing population aging. Acupuncture has been in practice in China for more than 3000 years and used to treat a wide variety of conditions including cardiovascular and psychiatric diseases, acute, and chronic pain. In this chapter, we review recent development on the effects and mechanisms of acupuncture on Alzheimer's disease. In Alzheimer's animal models, acupuncture stimulation at acupoints enhances cholinergic neurotransmission, trophic factor releasing, reduces apoptotic and oxidative damages, improves synaptic plasticity and decreases the levels of Aß proteins in the hippocampus and relevant brain regions. The biochemical modulations by acupuncture in the brains of Alzheimer's models are correlated with the cognitive improvement. In Alzheimer's patients, functional brain images demonstrated that acupuncture increased in the activity in the temporal lobe and prefrontal lobe which are related to the memory and cognitive function. Although only a few acupuncture clinical studies with a small number of participants are reported, they represent an important step forward in the research of both acupuncture and Alzheimer's. Translation of acupuncture research in animal model studies into the human subjects will undoubtedly enhance acupuncture efficacy in clinical study and treatment which could eventually lead to a safer, well-tolerated and inexpensive form of care for Alzheimer's patients.
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Terapia por Acupuntura , Enfermedad de Alzheimer/terapia , Encéfalo , Humanos , Imagen por Resonancia MagnéticaRESUMEN
Hyperinnervation of the striatum by serotoninergic (5-HT) terminals occurs after destruction of the dopaminergic nigro-striatal pathway. Recent studies have suggested that non-physiological release of dopamine (DA) formed from levodopa in these serotoninergic terminals underlies abnormal involuntary movement (AIMs) induction in 6-OHDA lesioned rats. In the present study, we used tryptophan hydroxylase (TPH) immunohistochemistry to determine whether 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) treatment and the induction of dyskinesia by levodopa alter the morphology of 5-HT fibres in the striatum of common marmosets. The caudate-putamen of normal monkeys contained numerous fine and smooth TPH positive fibres and numerous varicose fibres, but a marked hyperinnervation of TPH positive fibres characterised by a significant increase in the number and diameter of TPH positive axon varicosities was noted in the dorsal caudate and putamen of MPTP-intoxicated monkeys but not the globus pallidus. In MPTP-intoxicated marmosets that had received chronic levodopa treatment to induce dyskinesia, a further increase in the number and enlargement of TPH positive axonal varicosities in both caudate nucleus and putamen was evident. Following LID induction, a similar pattern of increase was also observed in the external segment of the globus pallidus, but only a significant varicosity enlargement was seen in the internal pallidal segment. These results confirm that striatal 5-HT hyperinnervation follows nigro-striatal pathway loss and provide the first evidence in primates that chronic levodopa treatment and the onset of dyskinesia are associated with a marked hypertrophy of striatal 5-HT axonal varicosities. These findings support the concept that altered 5-HT function may contribute to the genesis or expression of LID.
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Antiparkinsonianos/toxicidad , Cuerpo Estriado/patología , Discinesia Inducida por Medicamentos/patología , Globo Pálido/patología , Levodopa/toxicidad , Trastornos Parkinsonianos/patología , Animales , Callithrix , Cuerpo Estriado/efectos de los fármacos , Femenino , Globo Pálido/efectos de los fármacos , Inmunohistoquímica , Masculino , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Serotonina/metabolismo , Triptófano Hidroxilasa/metabolismoRESUMEN
Repeated subcutaneous administration of proteasome inhibitor 1 [PSI, Z-Ile-Glu(OtBu)-Ala-Leu-CHO] to rats causes progressive motor deficits and nigral dopaminergic cell loss in our laboratories, but this is controversial since others have not reproduced these findings. For this reason, we have investigated the role that the dose of PSI and its route of administration have on motor activity and neuronal loss in rat brain. PSI (8, 12 or 16 mg/kg, s.c.) was administered to female Wistar rats on 6 occasions on alternative days over 2 weeks. Subsequently PSI (8 mg/kg) was administered by oral, s.c. and i.p. routes on alternate days to separate groups of animals. Rats were assessed for motor function on a weekly basis up to 5 months after the end of PSI treatment. Locomotor activity was decreased following s.c. administration of 8 and 12 mg/kg PSI but not following 16 mg/kg. In subsequent experiments PSI (8 mg/kg) decreased motor activity after p.o. but not i.p. administration. PSI 8 mg/kg s.c. or p.o., but not i.p., caused neuronal loss in the substantia nigra, raphe nuclei, locus coeruleus, nucleus basalis of Meynert and dorsal motor nucleus of vagus. These data confirm that systemic administration of PSI reduces locomotor activity in rats and induces widespread neuronal degeneration in brain. However, the effects of PSI and its time course of action are dose and route dependent.
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Encéfalo/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Degeneración Nerviosa/patología , Neuronas/efectos de los fármacos , Oligopéptidos/administración & dosificación , Administración Oral , Análisis de Varianza , Animales , Encéfalo/metabolismo , Encéfalo/patología , Recuento de Células , Relación Dosis-Respuesta a Droga , Femenino , Inmunohistoquímica , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Degeneración Nerviosa/metabolismo , Neuronas/metabolismo , Neuronas/patología , Oligopéptidos/farmacología , Ratas , Ratas Wistar , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Dysfunction of the ubiquitin-proteasome system (UPS) occurs in dopaminergic neurones in the SN in PD and it is associated with Lewy body formation. However, it remains unknown whether this is specific to PD or whether it also occurs in multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) where nigral dopaminergic neurones also degenerate. In the present study, we investigated changes in the expression of proteasomal subunits in the SN in PD, MSA and PSP. Immunohistochemistry double staining showed that proteasome 20S-alpha4 and -alpha6, and 20S-beta3 and -beta5i subunits are colocalized with tyrosine hydroxylase (TH)-positive cells in the SN of control, PD, MSA and PSP brain. Semi-quantitative analysis showed a significant loss of 20S-alpha4 and -alpha6 subunits TH-positive cells in PD, MSA and PSP compared to control tissue. There was no change in the expression of 20S-beta3 and -beta5i subunits in any of the disease states. The expression of PA700-Rpt5 subunits was not changed in PSP or PD but was significantly increased in MSA compared to control SN. PA700-Rpn10 subunit was not colocalized with TH within dopamine cells but was co-expressed with glial fibrillary acid protein (GFAP) positive astrocytes in the SN of all groups. PA28-alpha immunoreactivity was low in TH positive neurones in control tissue and quantification was not possible. Qualitative analysis suggested a decrease in PD and no immunoreactivity was detected in MSA or PSP. The results show that changes in proteasomal structure occur in the SN in PD, MSA and PSP and that these are similar in nature suggesting that dysfunction of UPS is not specific to PD or to Lewy body formation.
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Atrofia de Múltiples Sistemas/patología , Enfermedad de Parkinson/patología , Complejo de la Endopetidasa Proteasomal/metabolismo , Sustancia Negra/metabolismo , Parálisis Supranuclear Progresiva/patología , Anciano , Anciano de 80 o más Años , Femenino , Regulación de la Expresión Génica/fisiología , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Neuronas/metabolismo , Neuronas/patología , Subunidades de Proteína/metabolismo , Sustancia Negra/patología , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Catechol-O-methyltransferase (COMT) inhibition is widely used to potentiate the effects of levodopa in Parkinson's disease but the effects of nigral dopaminergic cell loss and levodopa treatment on COMT activity are not known. The present study investigated the expression of COMT in the brain and liver of normal common marmosets, and animals treated with MPTP and those treated with levodopa to induce dyskinesia. Reverse transcript PCR demonstrated the expression of COMT mRNA in the liver, cortex and striatum of normal marmosets. Using Western blotting, the presence of two subunits of COMT protein, membrane bound COMT (MB-COMT) and soluble COMT (S-COMT), was shown in the liver, cortex and striatum of normal marmosets. Quantitative analysis of the MB-COMT and S-COMT subunit bands showed that there was no significant difference in the density of bands in MPTP treated marmosets or those exposed to levodopa compared to normal animals. COMT immunoreactivity was expressed in many brain regions including the cortex and striatum. No difference in COMT staining intensity was observed between normal, MPTP exposed or MPTP plus levodopa treated animals. COMT immunostaining was present in most striatal neurones and it was occasionally seen in glial cells. The data from present study demonstrated the expression of COMT mRNA and protein in the brain of common marmoset contrary to a previous report that it is not expressed in this species. COMT activity appears unaffected by loss of the dopaminergic nigro-striatal pathway and levodopa treatment.
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Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Catecol O-Metiltransferasa/metabolismo , Hígado/efectos de los fármacos , Hígado/enzimología , Intoxicación por MPTP/enzimología , Animales , Antiparkinsonianos/toxicidad , Callithrix , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/enzimología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/enzimología , Discinesia Inducida por Medicamentos/enzimología , Femenino , Levodopa/toxicidad , Masculino , Neuroglía/efectos de los fármacos , Neuroglía/enzimología , Neuronas/efectos de los fármacos , Neuronas/enzimología , ARN Mensajero/metabolismoRESUMEN
Systemic administration of the proteasomal inhibitor I (PSI) to rats was reported to cause progressive nigral dopaminergic neuronal loss but this is disputed. A major controversy centres over the use of manual counting of tyrosine hydroxylase (TH) positive neurons at the level of third cranial nerve as opposed to employing systematic stereological analysis of cell loss in the entire substantia nigra (SN). To provide a method of marking SN neurones independent of protein expression, fluorogold (FG) was stereotaxically injected bilaterally into the striatum of male Wistar rats to retrogradely label nigral dopaminergic neurons. After 1 week, animals were treated with six doses of PSI (8 mg/kg, s.c.) or its vehicle (dimethyl sulphoxide) on alternate days over a 2-week period. Five weeks after the last treatment, PSI-treated animals showed decreased spontaneous locomotor activity and reduced TH positive SN cell number at the level of the third cranial nerve compared to control rats. Manual cell counting showed loss of FG-labelled SN neurones at this level, with a subpopulation of surviving neurons displaying abnormal morphology. Manual counting of all FG-labelled cells in the entire SN also showed regional PSI-induced loss of neurones with both normal and compromised morphology. Stereological optical fractionator estimates of total FG-labelled cell number confirmed the manual cell counting data both at the level of the third cranial nerve and throughout the entire SN. These findings confirm that PSI does cause a persistent nigral dopaminergic neuronal loss. The reason for the lack of reproducibility between laboratories requires further investigation. We suggest that a failure to distinguish between TH-positive neurones with normal and abnormal morphology following PSI administration contributes to equivocal results.