Neuroprotective effects of sinapic acid involve the iron regulatory role on the rotenone-induced Parkinson's disease model

Abstract In the last decades, ferroptosis and its relationship with Parkinson's disease have gained significant attention. Compounds that affect ferroptosis and iron-dependent pathways in particular, have possible candidates for study in this context.Sinapic acid is an iron-chelator and high antioxidant bioactive phenolic acid. Its neuroprotective action, due to the antioxidant capacity, has been shown in several experimental models.However, the relationship between iron and antioxidant actions is still misunderstood and therefore, in the current study, we tried to investigate the effects of sinapic acid in rotenone-induced Parkinson's disease with the aspect of ferroptosis and iron-dependent alterations.The Parkinson's disease model was induced by a single dose intrastriatal and intrategmental rotenone (5µg/µl) injection.Sinapic acid (30mg/ kg) was orally administered during a 28-day period after the Parkinson's disease model was validated.Our results demonstrated that sinapic acid treatment attenuated rotenone-induced increase of serum transferrin and iron levels.Furthermore, sinapic acid inhibited rotenone-induced heme oxygenase-1(HO-1) increase and decrease of glutathione peroxidase-4 (GPx-4) levels in brain tissue. Also, sinapic acid treatment decreased motor impairment, likely as a result of the ameliorative effects on the tyrosine hydroxylase immunoreactivity loss after the rotenone insult.Our study suggests that the iron regulatory role of sinapic acid possibly plays a role in the protective effect on rotenone-induced neuronal damage.

Autophagy inhibitor 3-methyladenine could not modulate rotenone neurotoxicity in primary mesencephalic cell culture / El inhibidor de la autofagia 3-metiladenina no logra modular la neurotoxicidad de la rotenona en el cultivo primario de células mesencefálicas

Dysregulated autophagy, whether excessive or downregulated, has been thought to be associated with neurodegenerative disorders including Parkinson's disease. Accordingly, the present study was carried out to investigate whether 3-methyladenine, an autophagy inhibitor, can modulate the effects of rotenone on dopaminergic neurons in primary mesencephalic cell culture. Cultures were prepared from embryonic mouse mesencephala at gestation day 14. Four groups of cultures were treated on the 10th DIV for 48 h as follows: the first was kept as an untreated control, the second was treated with 3-methyladenine alone (1, 10, 100, 200 mM), the third was treated with 20 nM rotenone and the fourth was co-treated with 20 nM rotenone and 3-methyladenine (1, 10, 100, 200 mM). On the 12th DIV, cultured cells were stained immunohistochemically against tyrosine hydroxylase and culture media were used to measure the levels of lactate dehydrogenase. 3methyladenine had no effects on both the survival of dopaminergic neurons and the release of lactate dehydrogenase. Rotenone significantly decreased the number of dopaminergic neurons and increased the levels of lactate dehydrogenase in the culture media. When cultures concomitantly treated with 3-methyladenine and rotenone, 3-methyladenine had no effect against rotenone-induced dopaminergic cell damage and lactate dehydrogenase release into the culture medium. In conclusion, the autophagy inhibitor 3-methyladenine could not modulate rotenone-induced dopaminergic cell damage in primary mesencephalic cell culture.

Se estima que la autofagia desregulada, ya sea excesiva o con baja regulación, está asociada con trastornos neurodegenerativos, incluyendo la enfermedad de Parkinson. En consecuencia, el se realizó este estudio para investigar si la 3metiladenina, un inhibidor de la autofagia,puede modular los efectos de la rotenona en las neuronas dopaminérgicas en el cultivo primario de células mesencefálicas. Los cultivos se prepararon a partir de mesencéfalo de ratón embrionario el día 14 de gestación. Cuatro grupos de cultivos se trataron en el 10º DIV durante 48 h de la siguiente manera: el primer grupo se mantuvo como un control no tratado, el segundo se trató con 3-metiladenina sola (1, 10, 100, 200 mM), el tercer grupo se trató con rotenona 20 nM y el cuarto se trató conjuntamente con rotenona 20 nM y 3-metiladenina (1, 10, 100, 200 mM). En el 12º DIV; las células cultivadas fueron tratadas mediante tinción inmunohistoquímica en tirosina hidroxilasa y se usaron medios de cultivo para medir los niveles de lactato deshidrogenasa. La 3-metiladenina no tuvo efectos tanto en la supervivencia de las neuronas dopaminérgicas como en la liberación de lactato deshidrogenasa. La rotenona disminuyó significativamente el número de neuronas dopaminérgicas y se observó un aumento de los niveles de lactato deshidrogenasa en los medios de cultivo. Cuando los cultivos tratados concomitantemente con 3-metiladenina y rotenona, la 3metiladenina no tuvo efecto contra el daño celular dopaminérgico inducido por la rotenona y la liberación de lactato deshidrogenasa en el medio de cultivo. En conclusión, el inhibidor de la autofagia 3-metiladenina no moduló el daño celular dopaminérgico inducido por la rotenona en el cultivo celular mesencefálico primario.

Neuroprotective potential of polydatin against motor abnormalities and dopaminergic neuronal loss in rotenone induced Parkinson model / Potencial neuroprotector de la polidatina contra las anomalías motoras y la pérdida neuronal dopaminérgica en un modelo de Parkinson inducido por la rotenona

Among the neurodegenerative disorders, Parkinson disease (PD) is ranked as second most common. The pathological hallmark is selective degeneration of the dopaminergic neurons in the nigro-striatal regions of brain with appearance of the Lewy bodies. Present study explores the neuro-protective potential of polydatin in terms of amelioration of degeneration of dopaminergic neurons in nigro-striatal regions of brain and distorted neuromotor behavior in the rotenone model of Parkinson's disease. Thirty-six male Sprague Dawley rats were divided into three groups. Group A (control), Group B (rotenone treated) and Group C (rotenone+polydatin treated). Rotenone was administrated intraperitoneally (i.p) at a dose of 3 mg/kg/body weight while polydatin was given i.p. at a dose of 50 mg/ kg/body weight for four weeks. Then, animals were sacrificed; substantia nigra (SN) & striatum isolated from brain and five micron thick sections were prepared. Cresyl violet (CV), H&E and Immuno-histochemical staining using anti-TH antibody was done. Motor behavior was assessed weekly throughout the experiment using five different methods. Rotenone treated parkinsonian animals showed deterioration of motor behavior, weight loss, loss of dopaminergic neurons and diminished immune-reactivity in the sections from the nigrostriatal regions of these animals Polydatin+rotenone treatment showed contradicting effects to parkinsonism, with amelioration in weight loss, neuro-motor behavior, dopaminergic loss and immune-reactivity against dopaminergic neurons. Present study revealed a neuro-protective potential of polydatin in animal model of PD by ameliorating the neuro-motor abnormalities and degeneration of dopaminergic neurons in nigrostriatal regions.

Entre los trastornos neurodegenerativos, la enfermedad de Parkinson (EP) se clasifica como la segunda más común. El sello patológico es la degeneración selectiva de las neuronas dopaminérgicas en las regiones nigro-estriatales del cerebro, con la aparición de los cuerpos de Lewy. El presente estudio explora el potencial de protección neuronal de la polidatina en términos de la mejora de la degeneración de las neuronas dopaminérgicas en las regiones nigro-estriatales del cerebro y el comportamiento neuromotor distorsionado en el modelo de rotenona de la enfermedad de Parkinson. Treinta y seis ratas macho Sprague Dawley se dividieron en tres grupos: Grupo A (control), Grupo B (tratado con rotenona) y Grupo C (tratamiento con rotenona + polidatina). La rotenona se administró por vía intraperitoneal (i.p.) a una dosis de 3 mg/kg/peso corporal, mientras que la polidatina se administró i.p. a una dosis de 50 mg/kg/ peso corporal durante cuatro semanas. Posteriormente, los animales fueron sacrificados. Se aislaron la substantia nigra (SN) y cuerpo estriado de los cerebros y se realizaron secciones de cinco micras de espesor. Se realizó una tinción de violeta de cresilo (CV), H&E y tinción inmunohistoquímica usando anticuerpo anti-TH. El comportamiento motriz se evaluó semanalmente durante todo el experimento utilizando cinco métodos diferentes. Los animales parkinsonianos tratados con rotenona mostraron deterioro del comportamiento motriz, pérdida de peso, pérdida de neuronas dopaminérgicas y disminución de la reactividad inmune en las secciones de las regiones nigroestriadas. El tratamiento con polidatina + rotenona mostró efectos contrarios al parkinsonismo, con mejoría en la pérdida de peso, en el comportamiento motor, en la pérdida dopaminérgica y en la reactividad inmune contra las neuronas dopaminérgicas. El presente estudio reveló un potencial de protección neuronal de la polidatina en el modelo animal de la EP al mejorar las anomalías neuro-motoras y la degeneración de las neuronas dopaminérgicas en las regiones nigroestriatales.

Treadmill Exercise Improves Motor Function by Suppressing Purkinje Cell Loss in Parkinson Disease Rats / 대한배뇨장애요실금학회지

PURPOSE: Rotenone is the most widely used neurotoxin for the making Parkinson disease (PD) animal model. The neurodegenerative disorder PD shows symptoms, such as slowness of movements, tremor at resting, rigidity, disturbance of gait, and instability of posture. We investigated whether treadmill running improves motor ability using rotenone-caused PD rats. The effect of treadmill running on PD was also assessed in relation with apoptosis of cerebellar Purkinje cells. METHODS: Treadmill running was applied to the rats in the exercise groups for 30 minutes once a day for 4 weeks, starting 4 weeks after birth. We used rota-rod test for the determination of motor coordination and balance. In this experiment, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, immunohistochemistry for calbindin, glial fibrillary acidic protein (GFAP), Iba-1, and western blot analysis for Bax and Bcl-2 were performed. RESULTS: Treadmill running enhanced motor balance and coordination by preventing the loss of Purkinje cells in the cerebellar vermis. Treadmill running suppressed PD-induced expression of GFAP-positive reactive astrocytes and Iba-1-positive microglia, showing that treadmill running suppressed reactive astrogliosis and microglia activation. Treadmill running suppressed TUNEL-positive cell number and Bax expression and enhanced Bcl-2 expression, demonstrating that treadmill running inhibited the progress of apoptosis in the cerebellum of rotenone-induced PD rats. CONCLUSIONS: Treadmill running improved motor ability of the rotenone-induced PD rats by inhibiting apoptosis in the cerebellum. Apoptosis suppressing effect of treadmill running on rotenone-induced PD was achieved via suppression of reactive astrocyte and inhibition of microglial activation.

Preliminary optimization of a Chinese herbal medicine formula based on the neuroprotective effects in a rat model of rotenone-induced Parkinson's disease / 中西医结合学报

<p><b>OBJECTIVE</b>The main objective of this study was to preliminarily determine the optimum formulation of a Chinese herbal formula that may have neuroprotective effects against rotenone-induced Parkinson's disease (PD).</p><p><b>METHODS</b>Seven recipes were made from Dihuang (DH, Rehmannia glutinosa Libosch), Roucongrong (RCR, Cistanche deserticola Y.C.Ma), Niuxi (NX, Achyranthes bidentata Bl.) and Shanzhuyu (SZY, Cornus officinalis Sieb. et Zucc) in different proportions, according to the principles of uniform design (4 factors 7 levels). Tyrosine hydroxylase (TH)-positive neurons in substantia nigra pars compacta (SNpc) were detected by immunohistochemistry and rotenone-exposure days necessary to induce PD symptoms were recorded. To probe one likely mechanism of the formulas, echinacoside (ECH) concentrations of all seven recipes were determined by high-performance liquid chromatography and related to number of TH-positive neurons.</p><p><b>RESULTS</b>The data showed that recipe 4 (DH:RCR:SZY:NX = 1:1:1:1) and recipe 7 (DH:RCR:SZY:NX = 7:5:3:1) partially reversed rotenone-induced death of TH-positive neurons in the SNpc and significantly increased rotenone-exposed days compared with model group. Pharmacologically, there was not a strong correlation between ECH concentration and TH-positive neurons.</p><p><b>CONCLUSION</b>The investigated formulations of Chinese herbs had neuroprotective effects against PD models, and the neuroprotective effects were weakly related to the proportion of key herbs. However the neuroprotective effects of the formula may not result from a single active constituent.</p>

Aged Lewis rats exposed to low and moderate doses of rotenone are a good model for studying the process of protein aggregation and its effects upon central nervous system cell physiology / Ratos Lewis idosos expostos a baixa e moderada doses de rotenona são um bom modelo para estudar o processo de agregação proteica e seus efeitos sobre a fisiologia celular do sistema nervoso central

ABSTRACT Cell physiology is impaired before protein aggregation and this may be more relevant than inclusions themselves for neurodegeneration. The present study aimed to characterize an animal model to enable the analysis of the cell biology before and after protein aggregation. Ten-month-old Lewis rats were exposed either to 1 or 2 mg/kg/day of rotenone, delivered subcutaneously through mini-pumps, for one month. Hyperphosphorylated TAU, alpha-synuclein, amyloid-beta peptide and protein carbonylation (indicative of oxidative stress) were evaluated in the hippocampus, substantia nigra and locus coeruleus through immunohistochemistry or western blot. It was found that 2 mg/kg/day rotenone increased amyloid-beta peptide, hyperphosphorylation of TAU and alpha-synuclein. Rotenone at 1mg/kg/day did not alter protein levels. Protein carbonylation remained unchanged. This study demonstrated that aged Lewis rats exposed to a low dose of rotenone is a useful model to study cellular processes before protein aggregation, while the higher dose makes a good model to study the effects of protein inclusions.

RESUMO A fisiologia celular está prejudicada antes da agregação proteica podendo ser mais importante para a neurodegeneração do que as próprias inclusões. Assim, o objetivo deste estudo é caracterizar um modelo animal para analisar os mecanismos e efeitos da agregação proteica. Ratos Lewis com 10 meses de idade foram expostos a rotenona (1 ou 2 mg/kg/dia), administrada subcutaneamente, utilizando minibombas osmóticas. Os níveis de peptídeo beta-amiloide, TAU hiperfosforilada, alfa-sinucleína e proteínas carboniladas (indicativo de estresse oxidativo) foram avaliados por imunohistoquímica e western blot no hipocampo, substância negra e locus coeruleus. Foi demonstrado que 2 mg/kg/dia de rotenona promoveu aumento do peptídeo beta-amiloide, hiperfosforilação da TAU e alfa-sinucleína. Já 1 mg/kg/dia de rotenona não alterou os níveis dessas proteína nessas regiões. As proteínas carboniladas não se alteraram. Foi demonstrado que ratos Lewis idosos expostos a baixas doses de rotenona são modelo de estudo dos processos celulares antes da agregação proteica, enquanto 2 mg/kg/dia de rotenona permite estudos sobre os efeitos da agregação proteica.

Quercetin induces cell death by caspase-dependent and p38 MAPK pathway in EGFR mutant lung cancer cells / 고신대학교의과대학학술지

OBJECTIVES: The aim of this study was whether quercetin induces cell death by caspase and MAPK signaling pathway in EGFR mutant lung cancer cells. METHODS: PC-9 cells, EGFR mutant lung cancer cells, were treated various times and concentrations of quercetin and harvested and measured using MTT assay, DNA fragmentation, Western blotting, and FACS analysis. RESULTS: Treatment with quercetin in PC-9 cells resulted in inhibition of cell growth through apoptosis. Quercetin-induced apoptosis was associated with caspase-dependent manner. Quercetin also significantly increased levels of phosphor-p38 and decreased levels of phosphor-ERK, indicating that quercetin induces p38 MAPK signaling pathway in PC-9 cells. Quecetin treatment also generated the release of cytochrome c in PC-9 cells; however, pretreatment with rotenone or z-LEHD-fmk, significantly attenuated quercetin-induced apoptosis. CONCLUSIONS: Our data indicate that quercetin exhibits EGFR mutant lung cancer effects through apoptosis by caspase dependent and mitochondrial pathway.

Cryptotanshinone inhibits TNF-α-induced LOX-1 expression by suppressing reactive oxygen species (ROS) formation in endothelial cells

Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha (TNF-α) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of TNF-α on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe CM-DCFH2-DA. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. TNF-α induced LOX-1 expression in a dose- and time-dependent manner in endothelial cells. TNF-α induced ROS formation, phosphorylation of NF-κB p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. NF-κB inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited TNF-α-induced LOX-1 expression. CPT and NAC suppressed TNF-α-induced LOX-1 expression and phosphorylation of NF-κB p65 and ERK in rat aorta. These data suggested that TNF-α induced LOX-1 expression via ROS activated NF-κB/ERK pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT.

Propuesta de reformas a los prestadores públicos de servicios médicos en Chile: “fortaleciendo la opción pública” / A reform proposal to strengthen public health care

Currently, there is no discussion on the need to improve and strengthen the institutional health care modality of FONASA (MAI), the health care system used by the public services net and by most of the population, despite the widely known and long lasting problems such as waiting lists, hospital debt with suppliers, lack of specialists and increasing services purchase transference to the private sector, etc. In a dichotomous sectorial context, such as the one of health’s social security in Chile (the state on one side and the market on the other), points of view are polarized and stances tend to seek refuge within themselves. As a consequence, to protect the public solution is commonly associated with protecting the “status quo”, creating an environment that is reluctant to change. The author proposes a solution based on three basic core ideas, which, if proven effective, can strengthen each other if combined properly. These are: network financing management, governance of health care services in MAI and investments and human resources in networked self-managed institutions. The proposal of these core ideas was done introducing a reality testing that minimizes the politic complexity of their implementation.

[Effect of N-acetylcysteine on motor symptoms and parkin protein level in frontal cortex in rat model of Parkinson's disease]

Recent studies have shown that oxidative stress has a critical role in the pathophysiology of Parkinson's disease. Frontal cortex receives a great amount of dopaminergic neurons from nigrostriatal pathway and is one of the brain regions which aredamagedin Parkinson's disease. On the other hand anti-oxidant properties of Nacetylcysteine have been proven to occur via fortifying glutathione. Glutathione is one of the main intracellular anti-oxidant systems. Therefore our study was aimed to evaluate the effect of N-acetylcysteine in the management of Parkinson's disease. Male Wistar rats with age range of 10-12 months and weights of 400 +/- 50g received rotenone [2.5 mg/kg/48h ip] to induce Parkinson's disease model. NAC [25 or 50 mg/kg/48h ip] was administered one hour before rotenone injections. In order to measure the motor symptoms and verify the development of the model, rotarod test was performed. Moreover the frontal cortex parkin level, one of the crucial proteins in Parkinson's disease, was measured using western blot technique. The results indicated that N-acetylcysteine could prevent decline in the motor performance inrotarod test. In addition frontal cortex parkin level was significantly decreased in rotenone received animals while N-acetylcysteine prevented the reduction of parkin in this region. Our results indicated that that N-acetylcysteine could prevent the development of Parkinson's disease in this model which is probably due to its anti-oxidant properties

[Rasagiline protective effect On Rotenone-Induced Neurotoxicity in mice]

Background: Rasagiline is a selective monoamine oxidase [MAO] B inhibitor which has been approved for treatment of Parkinson's disease [PD]

Objectives: This study was performed to evaluate rotenone neurotoxicity in mice and to investigate the possible neuroprotective effect of rasagiline and its mechanism

Methods: Thirty six male mice were used and divided into three equal groups. The first group, the control group, received only sunflower oil intraperitoneally [IP] once daily at a volume of 4 ml/kg for 49 days. The second group was given rotenone [2 mg/kg/day; IP] for 49 days. The third group was given rasagiline [1 mg/kg, IP] which was administered 30 min prior to rotenone [2 mg/kg/day; IP] for 49 days. Behavioral tests were performed a day prior to drug administration and then once weekly along the duration of drugs or vehicle administration. At the end of the 49 days all animals were sacrificed and their midbrains were subjected to immunohistochemical analysis for dopaminergic neurons staining for anti-tyrosine hydroxylase [TH] antibodies. Midbrain tissues were also isolated for biochemical measurements

Results: Rasagiline administration significantly improved the mice activity. Pretreatment with rasagiline significantly attenuated rotenone-induced midbrain dopamine loss. Moreover, rasagiline treatment also significantly prevented the loss of TH immunoreactive neurons within the substantia nigra pars compacta [SNpc]. Furthermore, rasagiline inhibited the remarkable decrease in total antioxidant capacity as well as the increase in the malondialdehyde [MDA] level and nitric oxide generation induced by chronic rotenone administration

Conclusion: These results suggest that chronic intraperitoneal administration of rotenone induced PD-like disorder in mice. Moreover, these results suggest that rasagiline had neuroprotective effect against the rotenone-induced PD. This neuroprotective effect was mediated even in part by the antioxidant properties of rasagiline

L10P mutation in DJ-1 gene induced oxidative stress and mitochondrial disfunction / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of the L10P mutation on the cellular mitochondrial disfunction.@*METHODS@#Spectrophotometer, flow cytometry and electron microscope was utilized to examine cell viability, reactive oxygen species (ROS), mitochondrial transmembrane potential, complex I activity and mitochondrial morphous of the HEK293 monoclone cell lines, in which wild-type and L10P mutant DJ-1 protein are stably expressed.@*RESULTS@#Compared with the cell lines expressing empty vector, we found the ROS levels were elevated, the cell viability, mitochondrial transmembrane potential, complex I activity were reduced in the cells expressing L10P mutant DJ-1 protein (P<0.05). We also found mitochondria in these cells were swelling and some mitochondria were vacuolar degeneration. These phenomena were more obvious when rotenone was used. But in the cells expressing wild-type DJ-1, ROS levels were lower, the cell viability, mitochondrial transmembrane potential, and complex I activity were higher than other cell lines (P<0.05), especially under the induction of rotenone. These results suggested that L10P mutant DJ-1 protein probably lost the ability of anti-oxidative stress and affect the normal function of mitochondria.@*CONCLUSION@#The L10P DJ-1 mutation results in a toxic protein, which lacks the protective function of wild-type protein on mitochondria due to the decrease in the ability of anti-oxidative stress.

Redução da água corporal de renais crônicos em diálise peritoneal se associa com melhor controle da hipertensão arterial / Total body water reduction in subjects with chronic kidney disease on peritoneal dialysis is associated with a better hypertension control

Introdução: A hipertensão arterial tem alta prevalência em renais crônicos, sendo a hipervolemia um de seus fatores causais. Objetivo: Avaliar a influência da redução da volemia no controle pressórico e em parâmetros ecocardiográficos de pacientes renais crônicos em diálise peritoneal contínua. Métodos: Doze renais crônicos sem sinais clínicos de hipervolemia foram submetidos à intensificação da diálise com o objetivo de reduzir o peso corporal em 5%. A volemia foi avaliada pela bioimpedância elétrica e pela ultrassonografia de veia cava inferior (VCI). Os voluntários foram submetidos à monitorização ambulatorial da pressão arterial e a exame ecocardiográfico no período basal e após 5 semanas de intervenção. Resultados: Após a intensificação da ultrafiltração, houve redução significativa do peso corporal, da água extracelular e do diâmetro inspiratório da VCI, enquanto o índice de colapsamento da VCI não alterou de modo significativo. A despeito da redução do número de anti-hipertensivos, a pressão sistólica do período de sono reduziu de 138,4 ± 18,6 para 126,7 ± 18,0 mmHg, o descenso pressórico do sono aumentou e o diâmetro sistólico final do ventrículo esquerdo reduziu significantemente. Conclusão: A redução da volemia de pacientes em diálise peritoneal, clinicamente euvolêmicos, se associou a melhor controle pressórico e à diminuição do diâmetro sistólico final do ventrículo esquerdo. .

Introduction: Hypertension is highly prevalent in patients with chronic kidney disease and hypervolemia is one of the principal causes. Objective: To evaluate the influence of the reduction of volemia on blood pressure as well as on echocardiographic parameters in patients on continuous ambulatory peritoneal dialysis. Methods: Twelve patients with no clinical evidence of hypervolemia were submitted to an increase in the rate of the dialysis with the purpose of reducing body weight by 5%. The volemia was evaluated by electrical bioimpedance and by ultrasound of the inferior cava vena (ICV). Blood pressure was measured by ambulatory blood pressure monitoring and cardiac function was evaluated by echocardiography both at baseline and 5 weeks after the intervention period. Results: After the increase in the ultrafiltration, body weight, extracellular water and the inspiratory diameter of the ICV decreased significantly in parallel with a non-significant increase in the collapsing ICV index. Despite the reduction of anti-hypertensive drugs, systolic blood pressure during the sleep period decreased from 138.4 ± 18.6 to 126.7 ± 18.0 mmHg, the nocturnal blood pressure drop increased and the final systolic left ventricular diameter decreased significantly. Conclusion: Reduction of the volemia of patients on peritoneal dialysis, with no signs of hypervolemia, was associated with a better blood pressure control and with a decrease of the final systolic left ventricular diameter. .

Hemoplasma prevalence and hematological abnormalities associated with infection in three different cat populations from Southern Brazil / Prevalência da infecção por hemoplasmas e alterações hematológicas associadas à infecção em três diferentes populações de gatos do sul do Brasil

Three hemoplasma species are recognized in domestic cats: Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ and ‘Candidatus Mycoplasma turicensis’. We report the prevalence and hematological abnormalities of hemoplasma infection in 369 domestic cats from three different populations (blood donors, hospitalized cats and shelter cats) from Southern Brazil. Complete blood counts were performed at the time of blood collection, and DNA was extracted and tested by conventional PCR for each hemoplasma species. A total of 79 samples (21.40%) were positive for at least one species. The most prevalent hemoplasma was ‘Candidatus Mycoplasma haemominutum’, with 50/369 (13.55%) positive cats, followed by ‘Candidatus Mycoplasma turicensis’, 10/369 (2.71%), and Mycoplasma haemofelis, 8/369 (2.16%). Mycoplasma haemofelis and ‘Candidatus Mycoplasma haemominutum’ coinfection was observed in 4/369 (1.08%), whereas ‘Candidatus Mycoplasma haemominutum’ and ‘Candidatus Mycoplasma turicensis’ in 5/369 (1.35%). Three cats (0.81%) were infected with all three hemoplasmas. There was no association between infection and the different populations. Anemia was associated with Mycoplasma haemofelis and ‘Candidatus Mycoplasma haemominutum’, but not with ‘Candidatus Mycoplasma turicensis’. Male cats and cats with outdoor access were more likely to be infected. Although ‘Candidatus Mycoplasma haemominutum’ is believed to cause minimal or no hematological alterations, the infected cats studied herein were more likely to be anemic.

Três espécies de hemoplasmas são reconhecidas em gatos domésticos: Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ e ‘Candidatus Mycoplasma turicensis’. A prevalência e alterações hematológicas associadas à infecção por hemoplasmas foi estudada, em 369 gatos domésticos de três populações distintas (doadores de sangue, hospitais e gatos de abrigo) do Sul do Brasil. Foram realizados hemogramas completos no momento da coleta de sangue e as amostras tiveram seu DNA extraído e testado por PCR convencional para cada espécie de hemoplasmas. Setenta e nove amostras (21,40%) foram positivas para pelo menos uma espécie. O mais prevalente foi ‘Candidatus Mycoplasma haemominutum’ com 50/369 (13,55%) gatos positivos, seguidos por ‘Candidatus Mycoplasma turicensis’ com 10/369 (2,71%) e Mycoplasma haemofelis com 8/369 (2,16%). Coinfecção por Mycoplasma haemofelis e ‘Candidatus Mycoplasma haemominutum’ foi observada em 4/369 (1,08%), enquanto ‘Candidatus Mycoplasma haemominutum’ e ‘Candidatus Mycoplasma turicensis’ coinfectaram 5/369 (1,35%) gatos. Três (0,81%) gatos apresentaram infecção pelos três hemoplasmas. Não houve associação entre a infecção e as diferentes populações. Anemia foi associada com a infecção por Mycoplasma haemofelis e ‘Candidatus Mycoplasma haemominutum’, mas não com ‘Candidatus Mycoplasma turicensis’. Gatos machos e com acesso à rua apresentaram maior probabilidade de serem infectados. Embora se acredite que ‘Candidatus Mycoplasma haemominutum’ possa causar alterações hematológicas mínimas ou ausentes, gatos infectados encontrados neste estudo foram mais propensos à anemia.

Estudo da degradação da proteína Tau hiperfosforilada por vias independentes do proteassoma, em modelo experimental de neurodegeneração / Study of hyperphosphorylated Tau protein degradation by proteasome-independent pathways, in an experimental model of neurodegeneration

O desenvolvimento das doenças neurodegenerativas, como a doença de Alzheimer, está associado à presença de agregados proteicos contendo Tau hiperfosforilada (p-Tau). Esta disfunção da Tau leva a prejuízos na homeostase celular. Um mecanismo chave para diminuir e/ou prevenir os danos promovidos pelos agregados contendo Tau seria o estímulo de sua degradação. Neste sentido, a proposta do presente estudo foi analisar a degradação da proteína Tau após aumento da expressão exógena da cochaperona Bag-2, a qual influencia o sistema proteassomal de degradação; bem como avaliar a ativação dos sistemas de degradação, a fim de correlacionar estes sistemas em cultura de células primárias e organotípica do hipocampo de ratos. Os resultados mostraram que a rotenona foi capaz de aumentar os níveis de p-Tau e que a superexpressão de Bag-2, foi eficiente em prevenir e degradar a p-Tau. O mecanismo envolvido neste processo envolve a coordenação dos sistemas proteassomal e lisossomal, já que a Rab7 e a Rab24 (envolvidas na via lisossomal) mostraram-se diminuídas na fase que antecede a agregação proteica, enquanto houve aumento da Rab24 na presença dos agregados proteicos. Com relação ao peptídeo beta amiloide, foi demonstrado tendência de aumento de p-Tau acompanhado de diminuição da atividade proteassomal e lisossomal. O tratamento com PADK (ativador lisossomal) foi capaz de reverter este efeito nestas diferentes condições. A análise da interrelação entre os sistemas mostrou que uma inibição do proteassoma favorece a via lisossomal e que o inverso não se repete. Os resultados sugerem que a modulação das vias de degradação pode ser interessante para o estudo, prevenção e tratamento das doenças neurodegenerativas associadas à agregação de proteínas...

Neurodegenerative diseases, such as Alzheimer's, are associated to protein inclusions containing hyperphosphorylated Tau (p-Tau). It is well established that Tau dysfunction impairs cell homeostasis. A key mechanism to prevent and/or reduce the damage promoted by aggregates of Tau might be its degradation. In view of this, the aims of the present study are to evaluate p- Tau clearance following exogenous expression of Bag-2, which stimulates proteasome; as well as to analyze the activation of both lysosome and proteasome pathways in order to understand the crosstalk between these two systems in primary and organotypic cultures of rat hippocampus. Results showed that rotenone was able of increasing p-Tau that was prevented and degraded by Bag-2 overexpression. Mechanisms involved in this process involve the coordination of cell degradation systems, depending upon aggregation status, since Rab7 and Rab24 (involved in lysosomal pathway) were decreased before protein aggregation, while Rab24 increased in the presence of protein inclusions. Amyloid-beta peptide also increased p-Tau accompanied by decreased proteasome and lysosome activity. PADK (lysosomal activator) treatment reverted the inhibition promoted by amyloidbeta peptide. Inhibition of proteasome leads to activation of lysosome, but lysosome inhibition does not affect proteasome. Overall, results suggest that targeting degradation pathways might be useful to understand, prevent and treat neurodegenerative diseases associated with protein deposits...

Protective effect of baicalin against rotenone induced injury on PC12 cells / 中国中药杂志

<p><b>OBJECTIVE</b>To explore the protective effect of baicalin against rotenone-induced injury on PC12 cells, and the po-tential mechanism of action action was also explored.</p><p><b>METHOD</b>PC12 cells were injured by rotenone and were treated with different concentrations (0.1, 1, 10 μmol x L(-1)) of baicalin at the same time. Cell viability was analyzed by MTT, and morphology was observed by phase-contrast microscopy. The cell apoptosis was detected by flow cytometry by Annexin V-FITC/PI staining. The intracellular ROS level was determined by fluorescence microscope with DCF-DA staining. The expression of Bcl-2, Bax and Caspase-3 was analyzed by Western blot.</p><p><b>RESULT</b>The viability of PC12 cells exposure to rotenone for 24 hour was gradually decreased with dose escalating and 1.5 μmol x L was adopted to do the following experiment. Baicalin increased cell viability, improved cell morphology and decreased intracellular ROS level. Moreover, FACS indicated baicalin attenuated the apoptosis induced by rotenone significantly. Western blot showed that Bcl-2, Bax and Caspase-3 expression in rotenone-induced PC12 cells was reversed by baicalin.</p><p><b>CONCLUSION</b>This study has demonstrated that baicalin protects PC12 cells against rotenone-induced apoptosis, at least in part, by scavenging excessive ROS and inhibiting the mitochondrion-dependent apoptotic pathway.</p>

Zileuton, a 5-lipoxygenase inhibitor, attenuates mouse microglial cell-mediated rotenone toxicity in PC12 cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To examine the effect of a selective inhibitor of 5-lipoxygenase (5-LOX) zileuton on microglia-mediated rotenone neurotoxicity.</p><p><b>METHODS</b>The supernatant from different concentrations of rotenone-stimulated mouse microglia BV2 cells was used as the conditioned media (CM) for PC12 cells. The viability of PC12 cells was determined by MTT assay and lactate dehydrogenase (LDH) release. Cell death was observed by LDH release and double fluorescence staining with Hoechst/propidiumiodide (PI). The effect of zileuton on microglia-mediated rotenone toxicity was evaluated by the above methods.</p><p><b>RESULTS</b>Rotenone at 1-10 nmol/L was nontoxic to PC12 cells directly. However, the CM from BV2 cells that were treated with rotenone (1-10 nmol/L) resulted in toxicity of PC12 cells. The BV2 CM which stimulated with rotenone (1-10 nmol/L) induced morphological changes, reduced cell viability, and increased LDH release and cell necrosis in PC12 cells. Pretreatment of BV2 cells with the 5-LOX inhibitor zileuton (0.01-1 μmol/L) protected PC12 cells from the microglia-mediated rotenone toxicity.</p><p><b>CONCLUSION</b>The 5-LOX inhibitor zileuton effectively attenuates microglia-mediated rotenone toxicity in PC12 cells. These results suggest that 5-LOX pathway may be involved in neuronal death induced by microglial inflammation.</p>

Role of rotenone in mitochondrial oxidative damage and the underlying mechanisms / 中南大学学报(医学版)

Rotenone is one of the typical inhibitors of the complex I on the mitochondrial respiratory chain. Numerous studies showed when applied to live animals or cells, rotenone could lead to mitochondrial dysfunction, ROS augment, and thus oxidative damage to proteins, lipids and nucleic acids. Through exploring the process of ROS generation in mitochondria, the relationship between rotenone and mitochondrial ROS generation and the role of rotenone in DNA damage, we elucidated the mechanisms of rotenone induced-mitochondrial oxidative damage. At the same time, we attempted to explore the mtDNA damage and the mutation induced by rotenone.

Inhibitory effect of Akt inhibitor deguelin on the growth of PC-3 prostate cancer cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the inhibitory effect of Akt inhibitor deguelin on PC-3 human prostate cancer cell lines and its possible mechanism.</p><p><b>METHODS</b>PC-3 human prostate cancer cells were cultured in deguelin at the concentrations of 10, 100, 500 and 1 000 nmol/L for 24, 48 and 72 hours, respectively. Then the inhibitory effect of deguelin on the proliferation of the PC-3 cells was determined by MTT assay and that on the cell cycle was detected by flow cytometry. The expression levels of MDM2 and GSK3beta mRNA were measured by RT-PCR and those of MDM2 and GSK3beta proteins by Western blot.</p><p><b>RESULTS</b>At 24, 48 and 72 hours, the inhibition rates of deguelin on the proliferation of the PC-3 prostate cancer cells were (91.10 +/- 3.75), (86.39 +/- 1.16) and (79.51 +/- 2.63)% at 10 nmol/L, (82.46 +/- 3.65), (76.84 +/- 0.97) and (69.69 +/- 2.30) % at 100 nmol/L, (81.46 +/- 0.41), (75.56 +/- 1.12) and (54.07 +/- 3.21)% at 500 nmol/L, and (66.77 +/- 2.82), (58.22 +/- 0.35) and (39.34 +/- 2.40)% at 1000 nmol/L, all with statistically significant differences from the control group (P < 0.01). Deguelin at 10, 100, 500 and 1 000 nmol/L increased the cell cycles blocked in the G0/G1 phase ([62.4 +/- 2.2], [63.6 +/- 1.1 ], [65.0 +/- 0.3] and [66.5 +/- 1.9]%, P < 0.01) and reduced the percentage of the S-phase cells ([14.7 +/- 2.4], [11.1 +/- 5.2], [5.8 +/- 1.1] and [7.0 +/- 0.6]%, P < 0.01). RT-PCR and Western blot showed markedly up-regulated expressions of GSK3 P3 a3beta down-regulated expressions of MDM2 mRNA and proteins in the PC-3 cells treated with deguelin.</p><p><b>CONCLUSION</b>Akt inhibitor deguelin can inhibit the proliferation of PC-3 human prostate cancer cells by affecting the down-stream signal molecules GSK3P3 and betaDM2 in the Akt pathway.</p>

Effects of deguelin on the proliferation and apoptosis of human esophageal cancer cell Ec-109: an experimental research / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effects of deguelin on the apoptosis and proliferation of human esophageal cancer cell Ec-109, and to explore its possible mechanisms.</p><p><b>METHODS</b>Human esophageal cancer cells Ec-109 were in vitro cultured. They were divided into the blank control group, and 5, 10, 20, and 40 nmol/L deguelin groups. The inhibition on the proliferation was detected at 24, 48, and 72 h using CCK-8 assay. The early apoptosis rate at 24 h was detected by flow cytometry. The expressions of apoptosis-related proteins Bcl-2 and Bax were detected at 24 and 48 h respectively.</p><p><b>RESULTS</b>Compared with the blank control group at the same point, the growth inhibition rate in all deguelin groups increased at 24, 48, and 72 h, showing statistical difference (P <0.05). The early apoptosis rate was 4.37% +/- 0.35%, 6.71% +/-0.14%, 15.62% +/- 0.21%, and 19.78% +/- 0.15% in 5, 10, 20, and 40 nmol/L deguelin groups, respectively, showing statistical difference when compared with that of the blank control group (1.10% +/- 0.08%, P < 0.05). Compared with the blank control group, Bcl-2 protein expression obviously decreased, and Bax protein expression obviously increased in 10, 20, and 40 nmol/L deguelin groups, showing statistical difference (P <0.05). The aforesaid indices were in time- and dose-dependent manners.</p><p><b>CONCLUSION</b>Deguelin showed obvious effects on inhibiting the proliferation of Ec-109 cells and promoting their apoptosis, which was correlated with up-regulating Bax protein expression and down-regulating Bcl-2 protein expression.</p>