Neuroprotective Potential of a Novel Soluble Guanylate Cyclase Stimulator the Riociguat Alone or in a Combination Manner with Resveratrol in Experimental Stroke Model in Rats / Potencial Neuroprotector del Novedoso Estimulador de Guanilato Ciclasa Soluble, el Riociguat solo o en Combinación con Resveratrol en un Modelo Experimental de Ataque Cerebrovascular en Ratas

SUMMARY: In this study we aimed to examine the effect of novel vasodilatory drug Riociguat co-administration along resveratrol to recover neurodegeneration in experimental stroke injury. For that purpose, thirty-five adult female rats were divided into five groups (Control, MCAO, MCAO + R, MCAO + BAY, MCAO + C) of seven animals in each. Animals in Control group did not expose to any application during the experiment and sacrificed at the end of the study. Rats in the rest groups exposed to middle cerebral artery occlusion (MCAO) induced ischemic stroke. MCAO + R group received 30 mg/kg resveratrol, and MCAO + BAY group received 10 mg/kg Riociguat. The MCAO + C group received both drugs simultaneously. The drugs were administered just before the reperfusion, and the additional doses were administered 24h, and 48h hours of reperfusion. All animals in this study were sacrificed at the 72nd hour of experiment. Total brains were received for analysis. Results of this experiment indicated that MCAO led to severe injury in cerebral structure. Bax, IL-6 and IL-1ß tissue levels were up-regulated, but anti-apoptotic Bcl-2 immunoexpression was suppressed (p<0.05). In resveratrol and Riociguat treated animals, the neurodegenerations and apoptosis and inflammation associated protein expressions were improved compared to MCAO group, but the most success was obtained in combined treatment exposed animals in MCAO + C group. This study indicated that the novel soluble guanylate stimulator Riociguat is not only a potent neuroprotective drug in MCAO induced stroke, but also synergistic administration of Riociguat along with resveratrol have potential to increase the neuroprotective effect of resveratrol in experimental cerebral stroke exposed rats.

En este estudio, nuestro objetivo fue examinar el efecto de la coadministración del nuevo fármaco vasodilatador Riociguat junto con resveratrol para recuperar la neurodegeneración en lesiones por ataques cerebrovasculares experimentales. Para ello, se dividieron 35 ratas hembras adultas en cinco grupos (Control, MCAO, MCAO + R, MCAO + BAY, MCAO + C) de siete animales en cada uno. Los animales del grupo control no fueron sometidos a ninguna aplicación durante el experimento y se sacrificaron al final del estudio. Las ratas de los grupos expuestas a la oclusión de la arteria cerebral media (MCAO) indujeron un ataque cerebrovascular isquémico. El grupo MCAO + R recibió 30 mg/kg de resveratrol y el grupo MCAO + BAY recibió 10 mg/kg de Riociguat. El grupo MCAO + C recibió ambos fármacos simultáneamente. Los fármacos se administraron antes de la reperfusión y las dosis adicionales se administraron a las 24 y 48 horas de la reperfusión. Todos los animales en este estudio fueron sacrificados a las 72 horas del experimento. Se recibieron cerebros totales para su análisis. Los resultados indicaron que la MCAO provocaba lesiones graves en la estructura cerebral. Los niveles tisulares de Bax, IL-6 e IL- 1ß estaban regulados positivamente, pero se suprimió la inmunoexpresión antiapoptótica de Bcl-2 (p <0,05). En los animales tratados con resveratrol y Riociguat, las neurodegeneraciones y las expresiones de proteínas asociadas a la apoptosis y la inflamación mejoraron en comparación con el grupo MCAO, sin embargo el mayor éxito se obtuvo en el tratamiento combinado de animales expuestos en el grupo MCAO + C. Este estudio indicó que el nuevo estimulador de guanilato ciclasa soluble Riociguat no solo es un fármaco neuroprotector potente en el ataque cerebrovascular inducido por MCAO, sino que también la administración sinérgica de Riociguat junto con resveratrol tiene el potencial para aumentar el efecto neuroprotector del resveratrol en ratas experimentales expuestas a un ataque cerebrovascular.

Influences of Glabridin Treatment on Motor Function Recovery after Spinal Cord Injury / Influencia del Tratamiento con Glabridina en la Recuperación de la Función Motora después de una Lesión de la Médula Espinal

SUMMARY: Spinal cord injury (SCI) usually arises from compression due to traffic accidents and falls, resulting in varying degrees of movement, sensory loss, and possible paralysis. Glabridin (Gla) is a natural compound derived from licorice. It significantly affects drug development and medicine because of its anti-inflammatory, anti-oxidative, anti-tumoral, antibacterial, bone protective, cardiovascular protective, neuroprotective, liver protective, anti-obesity, and anti-diabetic properties. Various methods were employed to administer Gla to SCI mice in order to investigate its impact on the recovery of motor function. The mice were allocated into four cohorts using a randomization procedure. In the sham cohort, solely the lamina of vertebral arch was surgically exposed without causing any harm to the spinal cord tissue. Conversely, the injury cohort was subjected to spinal cord tissue damage and received no treatment thereafter. The mice in the remaining two cohorts received a dosage of 40 mg/kg Gla every two days via either intraperitoneal or intrathecal injection for a duration of 42 d following spinal cord injury. We conducted behavioral tests utilizing the Basso Mouse Scale score and gait analysis techniques. Magnetic resonance imaging and hematoxylin and eosin were employed to evaluate scar tissue formation. Systemic inflammation in mice was evaluated by employing an enzyme-linked immunosorbent assay. Gla promoted motor function recovery in mice following SCI and improved the pathological environment in the damaged area. These alterations were more evident in mice subjected to the intrathecal injection method. Intraperitoneal injections appear to be more beneficial for controlling systemic inflammatory responses. Although more intensive studies are required, Gla exhibits promising clinical potential as a cost-effective dietary phytochemical.

La lesión de la médula espinal (LME) generalmente surge de la compresión producto de caídas y accidentes de tránsito, lo que resulta en alteraciones del movimiento, pérdida sensorial y posible parálisis. La Glabridina (Gla) es un compuesto natural derivado del regaliz, constituyéndose en un aporte significativo para el desarrollo de fármacos y la medicina debido a sus propiedades antiinflamatorias, antioxidantes, antitumorales, antibacterianas, osteoprotectoras, cardioprotectoras, neuroprotectoras, hepatoprotectoras, antidiabéticas y contra la obesidad. En el presente trabajo se emplearon varios métodos para administrar Gla a ratones con lesión medular con el fin de investigar su impacto en la recuperación de la función motora. Los ratones fueron distribuidos en cuatro grupos mediante un procedimiento de aleatorización. En el grupo simulado, únicamente se expuso quirúrgicamente la lámina del arco vertebral sin causar ningún daño al tejido de la médula espinal. Por el contrario, el grupo lesionado fue sometido a daño del tejido de la médula espinal, sin recibir tratamiento posterior. Los ratones de los dos grupos restantes recibieron una dosis de 40 mg/kg de Gla cada dos días mediante inyección intraperitoneal o intratecal durante 42 días después de la lesión de la médula espinal. Fueron realizadas pruebas de comportamiento utilizando la puntuación de la escala Basso Mouse y técnicas de análisis de la marcha. Se emplearon imágenes por resonancia magnética y se aplicaron tinciones histológicas (Hematoxilina & Eosina) en muestras para evaluar la formación de tejido cicatricial. La inflamación sistémica en ratones se evaluó mediante el empleo de un ensayo inmunoabsorbente ligado a enzimas. Gla promovió la recuperación de la función motora en ratones después de una lesión medular y mejoró el entorno patológico en el área dañada. Estas alteraciones fueron más evidentes en ratones sometidos al método de inyección intratecal. Las inyecciones intraperitoneales parecen ser más beneficiosas para controlar las respuestas inflamatorias sistémicas. Aunque se requieren estudios más intensivos, Gla exhibe un potencial clínico prometedor como fitoquímico dietético rentable.

Neuroprotective effect of Capparis ovata Desf. var. palaestina Zoh. on H2O2­induced neurotoxicity in SH­SY5Y cells / Efecto neuroprotector de Capparis ovata Desf. var. palaestina Zoh. sobre la neurotoxicidad inducida por H2O2 en células SH ­SY5Y

The neuroprotective effect of flower and fruit parts of Capparis ovata Desf. var. palaestina Zoh. plant was investigated in H2O2-induced cytotoxicity in SH-SY5Y cells. The cells were treated with H2O2 alone or pretreated with flower (COMFL) and fruit extract (COMFR) of C. ovatavar. palaestina. MTT, xCELLigence, and qualitative and quantitative determination of phytochemical constituents in the extracts by LC-MS/MS methods were employed. COMFL and COMFR had a neuroprotective effect and this effect was stronger when the presence of oxidative stress. The mass spectrums revealed the presence of flavonoids and phenolic acid derivatives in the extracts. According to quantitative analyses, the main compounds were myristoleic acid, apigenin, caffeic acid, caffeic acid-3-glucoside, and 5-cynapoil quinic acid in both COMFL and COMFR and rutin was found in COMFL. The extracts could inhibit H2O2induced neuronal cell death which might be beneficial for the pretreatment of oxidative stress in neurodegenerative diseases.

Se investigó el efecto neuroprotector de flores y frutos de Capparis ovata Desf. var. palaestina Zoh sobre la citotoxicidad inducida por H2O2en células SH-SY5Y. Las células se trataron con H2O2solo o se pretrataron con extracto de flores (COMFL) y frutos (COMFR) de C. ovatavar. palaestina. Se emplearon MTT, xCELLigence y determinación cualitativa y cuantitativa de constituyentes fitoquímicos en los extractos mediante LC-MS/MS. COMFL y COMFR que tuvieron un efecto neuroprotector y este efecto fue mayor cuando hubo estrés oxidativo. Los espectros de masas revelaron la presencia de flavonoides y derivados del ácido fenólico en los extractos. Según los análisis cuantitativos, los compuestos principales fueron ácido miristoleico, apigenina, ácido cafeico, ácido cafeico-3-glucósido y ácido quínico 5-cinapoil tanto en COMFL como en COMFR y se encontró rutina en COMFL. Los extractos podrían inhibir la muerte celular neuronal inducida por H2O2, lo que podría ser beneficioso para el pretratamiento del estrés oxidativo en enfermedades neurodegenerativas.

The antioxidant effect of preischemic dexmedetomidine in a rat model: increased expression of Nrf2/HO-1 via the PKC pathway

Abstract Background The precise underlying mechanism of antioxidant effects of dexmedetomidine-induced neuroprotection against cerebral ischemia has not yet been fully elucidated. Activation of Nuclear factor erythroid 2-related factor (Nrf2) and Heme Oxygenase-1 (HO-1) represents a major antioxidant-defense mechanism. Therefore, we determined whether dexmedetomidine increases Nrf2/HO-1 expression after global transient cerebral ischemia and assessed the involvement of Protein Kinase C (PKC) in the dexmedetomidine-related antioxidant mechanism. Methods Thirty-eight rats were randomly assigned to five groups: sham (n = 6), ischemic (n = 8), chelerythrine (a PKC inhibitor; 5 mg.kg-1 IV administered 30 min before cerebral ischemia) (n = 8), dexmedetomidine (100 µg.kg-1 IP administered 30 min before cerebral ischemia (n = 8), and dexmedetomidine + chelerythrine (n = 8). Global transient cerebral ischemia (10 min) was applied in all groups, except the sham group; histopathologic changes and levels of nuclear Nrf2 and cytoplasmic HO-1 were examined 24 hours after ischemia insult. Results We found fewer necrotic and apoptotic cells in the dexmedetomidine group relative to the ischemic group (p< 0.01) and significantly higher Nrf2 and HO-1 levels in the dexmedetomidine group than in the ischemic group (p< 0.01). Additionally, chelerythrine co-administration with dexmedetomidine attenuated the dexmedetomidine-induced increases in Nrf2 and HO-1 levels (p< 0.05 and p< 0.01, respectively) and diminished its beneficial neuroprotective effects. Conclusion Preischemic dexmedetomidine administration elicited neuroprotection against global transient cerebral ischemia in rats by increasing Nrf2/HO-1 expression partly via PKC signaling, suggesting that this is the antioxidant mechanism underlying dexmedetomidine-mediated neuroprotection.

Applicability of [18F]FDG/PET for investigating rosmarinic acid preconditioning efficacy in a global stroke model in mice

ABSTRACT Positron emission tomography (PET) is a non-invasive nuclear imaging technique that uses radiotracers to track cell activity. The radiopharmaceutical 18F-fluoro-2-deoxyglucose ([18F] FDG) is most commonly used in nuclear medicine for the diagnosis of various diseases, including stroke. A stroke is a serious condition with high mortality and morbidity rates. Rosmarinic acid (RA) is a promising therapeutic agent that exerts neuroprotective effects against various neurological diseases. Therefore, this study aimed to evaluate the applicability of [18F]FDG/PET for investigating the neuroprotective effects of RA in case of a global stroke model in mice. The [18F]FDG/PET technique facilitates the observation of ischemia and reperfusion injuries in the brain. Moreover, the recovery of glucose metabolism in three specific brain regions, the striatum, superior colliculus, and inferior colliculus, was observed after preconditioning with RA. It was concluded that the [18F]FDG/PET technique may be useful for stroke diagnosis and the assessment of treatment response. In addition, a long-term longitudinal study using biochemical analysis in conjunction with functional imaging may provide further conclusive results regarding the effect of RA on cerebral ischemia.

Neuroprotective potential of the Amazonian fruits Euterpe oleracea Mart. and Paullinia cupana Kunth

Abstract Acai (Euterpe oleracea Mart.) and guarana (Paullinia cupana Kunth) are native species from the Amazon Forest that in folk medicine are used to treat several diseases due to their anti-inflammatory and antioxidant properties. This review brings together findings from different studies on the potential neuroprotective effects of acai and guarana, highlighting the importance of the conservation and sustainable exploitation of the Amazon Forest. A bibliographic survey in the PubMed database retrieved indexed articles written in English that focused on the effects of acai and guarana in in vitro and in vivo models of neurodegenerative diseases. In general, treatment with either acai or guarana decreased neuroinflammation, increased antioxidant responses, ameliorated depression, and protected cells from neurotoxicity mediated by aggregated proteins. The results from these studies suggest that flavonoids, anthocyanins, and carotenoids found in both acai and guarana have therapeutic potential not only for neurodegenerative diseases, but also for depressive disorders. In addition, acai and guarana show beneficial effects in slowing down the physiological aging process. However, toxicity and efficacy studies are still needed to guide the formulation of herbal medicines from acai and guarana.

Neuroprotective effects of the PPARß/δ antagonist GSK0660 in in vitro and in vivo Parkinson's disease models

BACKGROUND: The underlying mechanism of Parkinson's disease are still unidentified, but excitotoxicity, oxidative stress, and neuroinflammation are considered key actors. Proliferator activated receptors (PPARs) are transcription factors involved in the control of numerous pathways. Specifically, PPARß/δ is recognized as an oxidative stress sensor, and we have previously reported that it plays a detrimental role in neurodegeneration. METHODS: Basing on this concept, in this work, we tested the potential effects of a specific PPARß/δ antagonist (GSK0660) in an in vitro model of Parkinson's disease. Specifically, live-cell imaging, gene expression, Western blot, proteasome analyses, mitochondrial and bioenergetic studies were performed. Since we obtained promising results, we tested this antagonist in a 6-hydroxydopamine hemilesioned mouse model. In the animal model, behavioral tests, histological analysis, immunofluorescence and western blot of substantia nigra and striatum upon GSK0660 were assayed. RESULTS: Our findings suggested that PPARß/δ antagonist has neuroprotective potential due to neurotrophic support, anti-apoptotic and anti-oxidative effects paralleled to an amelioration of mitochondria and proteasome activity. These findings are strongly supported also by the siRNA results demonstrating that by silencing PPARß/δ a significative rescue of the dopaminergic neurons was obtained, thus indicating an involvement of PPARß/δ in PD's pathogenesis. Interestingly, in the animal model, GSK0660 treatment confirmed neuroprotective effects observed in the in vitro studies. Neuroprotective effects were highlighted by the behavioural performance and apomorphine rotation tests amelioration and the reduction of dopaminergic neuronal loss. These data were also confirmed by imaging and western blotting, indeed, the tested compound decreased astrogliosis and activated microglia, concomitant with an upregulation of neuroprotective pathways. CONCLUSIONS: In summary, PPARß/δ antagonist displayed neuroprotective activities against 6-hydroxydopamine detrimental effects both in vitro and in vivo models of Parkinson's disease, suggesting that it may represent a novel therapeutic approach for this disorder.

Neuroprotective potential of sevoflurane against isoflurane induced cognitive dysfunction in rats via anti-inflammatory and antioxidant effect

Purpose: Intravenous anesthetics have excellent analgesic activity without inducing the side effect in the respiratory system. The aim and objective of the current experimental study was to access the neuroprotective effect of sevoflurane against isoflurane induced cognitive dysfunction in rats. Methods: Isoflurane was used for induction the neurodysfunction in the rats, and rats received the oral administration of sevoflurane (2.5, 5 and 10 mg/kg). Morris water test was carried out for the estimation of cognitive function. Neurochemical parameters, antioxidant parameters and pro-inflammatory cytokines were also estimated. Results: Sevoflurane significantly (P < 0.001) altered the neurochemical parameters such as anti-choline acetyltransferase, acetylcholine esterase, acetylcholine, protein carbonyl, choline brain-derived neurotrophic factor, and amyloid ß; antioxidant parameters such as glutathione, superoxide dismutase, and malondialdehyde; pro-inflammatory cytokines include interleukin (IL-2, IL-10, IL-4, IL-6, IL-10, IL-1ß), and tumor necrosis factor-α. Sevoflurane significantly reduced the activity of caspase-3. Conclusions: Sevoflurane exhibited the neuroprotection against the cognitive dysfunction in rats via anti-inflammatory and antioxidant mechanism.

Protective effects of histone deacetylase 6 specific inhibitor tubastatin A on subarachnoid hemorrhage in rats and the underlying mechanisms / 中南大学学报(医学版)

OBJECTIVES@#Subarachnoid hemorrhage (SAH) is a serious cerebrovascular disease. Early brain injury (EBI) and cerebral vasospasm are the main reasons for poor prognosis of SAH patients. The specific inhibitor of histone deacetylase 6 (HDAC6), tubastatin A (TubA), has been proved to have a definite neuroprotective effect on a variety of animal models of acute and chronic central nervous system diseases. However, the neuroprotective effect of TubA on SAH remains unclear. This study aims to investigate the expression and localization of HDAC6 in the early stage of SAH, and to evaluate the protective effects of TubA on EBI and cerebral vasospasm after SAH and the underlying mechanisms.@*METHODS@#Adult male SD rats were treated with modified internal carotid artery puncture to establish SAH model. In the first part of the experiment, rats were randomly divided into 6 groups: a sham group, a SAH-3 h group, a SAH-6 h group, a SAH-12 h group, a SAH-24 h group, and a SAH-48 h group. At 3, 6, 12, and 24 h after SAH modeling, the injured cerebral cortex of rats in each group was taken for Western blotting to detect the expression of HDAC6. In addition, the distribution of HDAC6 in the cerebral cortex of the injured side was measured by immunofluorescence double staining in SAH-24 h group rats. In the second part, rats were randomly divided into 4 groups: a sham group, a SAH group, a SAH+TubAL group (giving 25 mg/kg TubA), and a SAH+TubAH group (giving 40 mg/kg TubA). At 24 h after modeling, the injured cerebral cortex tissue was taken for Western blotting to detect the expression levels of HDAC6, endothelial nitric oxide synthase (eNOS), and inducible nitric oxide synthase (iNOS), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining to detect apoptosis, and hematoxylin and eosin (HE) staining to detect the diameter of middle cerebral artery.@*RESULTS@#The protein expression of HDAC6 began to increase at 6 h after SAH (P<0.05), peaked at 24 h (P<0.001), and decreased at 48 h, but there was still a difference compared with the sham group (P<0.05). HDAC6 is mainly expressed in the cytoplasm of the neurons. Compared with the sham group, the neurological score was decreased significantly and brain water content was increased significantly in the SAH group (both P<0.01). Compared with the SAH group, the neurological score was increased significantly and brain water content was decreased significantly in the SAH+TubAH group (both P<0.05), while the improvement of the above indexes was not significant in the SAH+TubAL group (both P>0.05). Compared with the sham group, the expression of eNOS was significantly decreased (P<0.01) and the expressions of iNOS and HDAC6 were significantly increased (P<0.05 and P<0.01, respectively) in the SAH group. Compared with the SAH group, the expression of eNOS was significantly increased, and iNOS and HDAC6 were significantly decreased in the SAH+TubA group (all P<0.05). Compared with the SAH group, the number of TUNEL positive cells was significantly decreased and the diameter of middle cerebral artery was significantly increased in the SAH+TubA group (both P<0.05) .@*CONCLUSIONS@#HDAC6 is mainly expressed in neurons and is up-regulated in the cerebral cortex at the early stage of SAH. TubA has protective effects on EBI and cerebral vasospasm in SAH rats by reducing brain edema and cell apoptosis in the early stage of SAH. In addition, its effect of reducing cerebral vasospasm may be related to regulating the expression of eNOS and iNOS.

Neuroprotective effect of ginsenoside Re on drosophila model of Parkinson's disease / 中国中药杂志

This study aims to explore the neuroprotective mechanism of ginsenoside Re(GS-Re) on drosophila model of Parkinson's disease(PD) induced by rotenone(Rot). To be specific, Rot was used to induce PD in drosophilas. Then the drosophilas were grouped and respectively treated(GS-Re: 0.1, 0.4, 1.6 mmol·L~(-1); L-dopa: 80 μmol·L~(-1)). Life span and crawling ability of drosophilas were determined. The brain antioxidant activity [content of catalase(CAT), malondialdehyde(MDA), reactive oxygen species(ROS), superoxide dismutase(SOD)], dopamine(DA) content, and mitochondrial function [content of adenosine triphosphate(ATP), NADH:ubiquinone oxidoreductase subunit B8(NDUFB8) Ⅰ activity, succinate dehydrogenase complex, subunit B(SDHB) Ⅱ activity] were detected by enzyme-linked immunosorbent assay(ELISA). The number of DA neurons in the brains of drosophilas was measured with the immunofluorescence method. The levels of NDUFB8 Ⅰ, SDHB Ⅱ, cytochrome C(Cyt C), nuclear factor-E2-related factor 2(Nrf2), heme oxygenase-1(HO-1), B-cell lymphoma/leukemia 2(Bcl-2)/Bcl-2-assaciated X protein(Bax), and cleaved caspase-3/caspase-3 in the brain were detected by Western blot. The results showed that model group [475 μmol·L~(-1) Rot(IC_(50))] demonstrated significantly low survival rate, obvious dyskinesia, small number of neurons and low DA content in the brain, high ROS level and MDA content, low content of SOD and CAT, significantly low ATP content, NDUFB8 Ⅰ activity, and SDHB Ⅱ activity, significantly low expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax, large amount of Cyt C released from mitochondria to cytoplasm, low nuclear transfer of Nrf2, and significantly high expression of cleaved caspase-3/caspase-3 compared with the control group. GS-Re(0.1, 0.4, and 1.6 mmol·L~(-1)) significantly improved the survival rate of PD drosophilas, alleviated the dyskinesia, increased DA content, reduced the loss of DA neurons, ROS level, and MDA content in brain, improved content of SOD and CAT and antioxidant activity in brain, maintained mitochondrial homeostasis(significantly increased ATP content and activity of NDUFB8 Ⅰ and SDHB Ⅱ, significantly up-regulated expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax), significantly reduced the expression of Cyt C, increased the nuclear transfer of Nrf2, and down-regulated the expression of cleaved caspase-3/caspase-3. In conclusion, GS-Re can significantly relieve the Rot-induced cerebral neurotoxicity in drosophilas. The mechanism may be that GS-Re activates Keap1-Nrf2-ARE signaling pathway by maintaining mitochondrial homeostasis, improves antioxidant capacity of brain neurons, then inhibits mitochondria-mediated caspase-3 signaling pathway, and the apoptosis of neuronal cells, thereby exerting the neuroprotective effect.

Neuroprotective effect of tetramethylpyrazine on mice after spinal cord injury / 中国中药杂志

This study aims to investigate the neuroprotective effect of tetramethylpyrazine on mice after spinal cord injury and its mechanism. Seventy-five female C57BL/6 mice were randomly divided into 5 groups, namely, a sham operation group, a model group, a tetramethylpyrazine low-dose group(25 mg·kg~(-1)), a tetramethylpyrazine medium-dose group(50 mg·kg~(-1)), and a tetramethylpyrazine high-dose group(100 mg·kg~(-1)), with 15 mice in each group. Modified Rivlin method was used to establish the mouse model of acute spinal cord injury. After 14 d of tetramethylpyrazine intervention, the motor function of hind limbs of mice was evaluated by basso mouse scale(BMS) and inclined plate test. The levels of inflammatory cytokines tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), and interleukin-1β(IL-1β) in the spinal cord homogenate were determined by enzyme-linked immunosorbent assay(ELISA). Hematoxylin-eosin(HE) staining was used to observe the histology of the spinal cord, and Nissl's staining was used to observe the changes in the number of neurons. Western blot and immunofluorescence method were used to detect the expression of glial fibrillary acidic protein(GFAP) and C3 protein. Tetramethylpyrazine significantly improved the motor function of the hind limbs of mice after spinal cord injury, and the BMS score and inclined plate test score of the tetramethylpyrazine high-dose group were significantly higher than those of the model group(P<0.01). The levels of TNF-α, IL-6, and IL-1β in spinal cord homogenate of the tetramethylpyrazine high-dose group were significantly decreased(P<0.01). After tetramethylpyrazine treatment, the spinal cord morphology recovered, the number of Nissl bodies increased obviously with regular shape, and the loss of neurons decreased. As compared with the model group, the expression of GFAP and C3 protein was significantly decreased(P<0.05,P<0.01) in tetramethylpyrazine high-dose group. In conclusion, tetramethylpyrazine can promote the improvement of motor function and play a neuroprotective role in mice after spinal cord injury, and its mechanism may be related to inhibiting inflammatory response and improving the hyperplasia of glial scar.

Neuroprotective potential of cannabidiol: Molecular mechanisms and clinical implications / 中西医结合学报

Cannabidiol (CBD), a nonpsychotropic phytocannabinoid that was once largely disregarded, is currently the subject of significant medicinal study. CBD is found in Cannabis sativa, and has a myriad of neuropharmacological impacts on the central nervous system, including the capacity to reduce neuroinflammation, protein misfolding and oxidative stress. On the other hand, it is well established that CBD generates its biological effects without exerting a large amount of intrinsic activity upon cannabinoid receptors. Because of this, CBD does not produce undesirable psychotropic effects that are typical of marijuana derivatives. Nonetheless, CBD displays the exceptional potential to become a supplementary medicine in various neurological diseases. Currently, many clinical trials are being conducted to investigate this possibility. This review focuses on the therapeutic effects of CBD in managing neurological disorders like Alzheimer's disease, Parkinson's disease and epilepsy. Overall, this review aims to build a stronger understanding of CBD and provide guidance for future fundamental scientific and clinical investigations, opening a new therapeutic window for neuroprotection. Please cite this article as: Tambe SM, Mali S, Amin PD, Oliveira M. Neuroprotective potential of Cannabidiol: Molecular mechanisms and clinical implications. J Integr Med. 2023; 21(3): 236-244.

Xixin Decoction improves learning and memory ability of SAMP8 by enhancing neuroprotective effect and inhibiting neuroinflammation / 中国中药杂志

This study aimed to explore the possible effect of Xixin Decoction(XXD) on the learning and memory ability of Alzheimer's disease(AD) model senescence-accelerated mouse-prone 8(SAMP8) and the related mechanism in enhancing neuroprotective effect and reducing neuroinflammation. Forty SAMP8 were randomly divided into a model group(10 mL·kg~(-1)·d~(-1)), a probiotics group(0.39 g·kg~(-1)·d~(-1)), a high-dose group of XXD granules(H-XXD, 5.07 g·kg~(-1)·d~(-1)), a medium-dose group of XXD granules(M-XXD, 2.535 g·kg~(-1)·d~(-1)), and a low-dose group of XXD granules(L-XXD, 1.267 5 g·kg~(-1)·d~(-1)). Eight senescence-accelerated mouse-resistant 1(SAMR1) of the same age and strain were assigned to the control group(10 mL·kg~(-1)·d~(-1)). After ten weeks of intragastric administration, the Morris water maze was used to test the changes in spatial learning and memory ability of mice after treatment. Meanwhile, immunofluorescence staining was used to detect the positive expression of receptor for advanced glycation end products(AGER), Toll-like receptor 1(TLR1), and Toll-like receptor 2(TLR2) in the hippocampal CA1 region of mice. Western blot was employed to test the protein expression levels of silencing information regulator 2 related enzyme 1(SIRT1), AGER, TLR1, and TLR2 in the hippocampus of mice. Enzyme linked immunosorbent assay(ELISA) was applied to assess the levels of Aβ_(1-42) in the hippocampus of mice and the levels of nuclear factor κB p65(NF-κB p65), NOD-like receptor protein 3(NLRP3), tumor necrosis factor-α(TNF-α), and interleukin-1β(IL-1β) in the serum and hippocampus of mice. Compared with the model group, XXD significantly improved the spatial learning and memory ability of SAMP8, increased the expression of neuroprotective factors in the hippocampus, decreased the levels of neuroinflammatory factors, and inhibited the expression of Aβ_(1-42). In particular, H-XXD significantly increased the expression of SIRT1 in the hippocampus of mice, reduced the expression levels of NF-κB p65, NLRP3, TNF-α, and IL-1β in the serum and hippocampus of mice, and decreased the expression of AGER, TLR1, and TLR2 in the hippocampus of mice(P<0.05 or P<0.01). XXD may improve the spatial learning and memory ability of AD model SAMP8 by enhancing the neuroprotective effect and inhibiting neuroinflammation.

Neuroprotective effect and mechanism of Zuogui Jiangtang Jieyu Formula on diabetes mellitus complicated with depression model rats based on CX3CL1-CX3CR1 axis / 中国中药杂志

Based on the CX3C chemokine ligand 1(CX3CL1)-CX3C chemokine receptor 1(CX3CR1) axis, this study explored the potential mechanism by which Zuogui Jiangtang Jieyu Formula(ZGJTJY) improved neuroinflammation and enhanced neuroprotective effect in a rat model of diabetes mellitus complicated with depression(DD). The DD rat model was established by feeding a high-fat diet combined with streptozotocin(STZ) intraperitoneal injection for four weeks and chronic unpredictable mild stress(CUMS) combined with isolated cage rearing for five weeks. The rats were divided into a control group, a model group, a positive control group, an inhibitor group, and a ZGJTJY group. The open field test and forced swimming test were used to assess the depression-like behaviors of the rats. Enzyme-linked immunosorbent assay(ELISA) was performed to measure the expression levels of the pro-inflammatory cytokines interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) in plasma. Immunofluorescence staining was used to detect the expression of ionized calcium-binding adapter molecule 1(Iba1), postsynaptic density protein-95(PSD95), and synapsin-1(SYN1) in the hippocampus. Hematoxylin-eosin(HE) staining, Nissl staining, and TdT-mediated dUTP nick end labeling(TUNEL) fluorescence staining were performed to assess hippocampal neuronal damage. Western blot was used to measure the expression levels of CX3CL1, CX3CR1, A2A adenosine receptor(A2AR), glutamate receptor 2A(NR2A), glutamate receptor 2B(NR2B), and brain-derived neurotrophic factor(BDNF) in the hippocampus. Compared with the model group, the ZGJTJY group showed improved depression-like behaviors in DD rats, enhanced neuroprotective effect, increased expression of PSD95, SYN1, and BDNF(P<0.01), and decreased expression of Iba1, IL-1β, and TNF-α(P<0.01), as well as the expression of CX3CL1, CX3CR1, A2AR, NR2A, and NR2B(P<0.01). These results suggest that ZGJTJY may exert its neuroprotective effect by inhibiting the CX3CL1-CX3CR1 axis and activation of hippocampal microglia, thereby improving neuroinflammation and abnormal activation of N-methyl-D-aspartate receptor(NMDAR) subunits, and ultimately enhancing the expression of synaptic-related proteins PSD95, SYN1, and BDNF in the hippocampus.

Neuroprotective effect and mechanism of cPLA2 inhibitor increases autophagic flux on spinal cord injury / 中国骨伤

OBJECTIVE@#To investigate the mechanism of cytosolic phospholipase A2(cPLA2) inhibitor to improve neurological function after spinal cord injury (SCI).@*METHODS@#Thirty-six 3 months old female SD rats, with body mass (280±20) g, were divided into three groups (n=12):sham group, SCI group, and SCI+ arachidonyl trifluoromethyl ketone(AACOCF3) group. Balloon compression SCI model was established in all three groups. In the sham model group, the spinal cord compression model was created after the balloon was placed without pressure treatment, and the remaining two groups were pressurized with the balloon for 48 h. After successful modeling, rats in the SCI+AACOCF3 group were injected intraperitoneally with AACOCF3, a specific inhibitor of cPLA2. The remaining two groups of rats were injected intraperitoneally with saline. The animals were sacrificed in batches on 7 and 14 days after modeling, respectively. And the damaged spinal cord tissues were sampled for pathomorphological observation, to detect the expression of cPLA2 and various autophagic fluxPrelated molecules and test the recovery of motor function.@*RESULTS@#Spinal cord histomorphometry examination showed that the spinal cord tissue in the sham group was structurally intact, with normal numbers and morphology of neurons and glial cells. In the SCI group, spinal cord tissue fractures with large and prominent spinal cord cavities were seen. In the SCI+AACOCF3 group, the spinal cord tissue was more intact than in the SCI group, with more fused spinal cord cavities, more surviving neurons, and less glial cell hyperplasia. Western blot showed that the sham group had the lowest protein expression of LC3-Ⅱ, Beclin 1, p62, and cPLA2 compared with the SCI and SCI+AACOCF3 groups (P<0.05) and the highest protein expression of LC3-Ⅰ (P<0.05). P62 and cPLA2 expression in the SCI group were higher than in the SCI+AACOCF3 group (P<0.05). Behavioral observations showed that the time corresponding to BBB exercise scores was significantly lower in both the SCI and SCI+AACOCF3 groups than in the sham group (P<0.05). Scores at 3, 7, and 14 days after pressurization were higher in the SCI+AACOCF3 group than in the SCI group (P<0.05).@*CONCLUSION@#cPLA2 inhibitors can reduce neuronal damage secondary to SCI, promote neurological recovery and improve motor function by improving lysosomal membrane permeability and regulating autophagic flux.

Total Saponins of Panax notoginseng Activate Akt/mTOR Pathway and Exhibit Neuroprotection in vitro and in vivo against Ischemic Damage / 中国结合医学杂志

OBJECTIVE@#To reveal the neuroprotective effect and the underlying mechanisms of a mixture of the main components of Panax notoginseng saponins (TSPN) on cerebral ischemia-reperfusion injury and oxygen-glucose deprivation/reoxygenation (OGD/R) of cultured cortical neurons.@*METHODS@#The neuroprotective effect of TSPN was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry and live/dead cell assays. The morphology of dendrites was detected by immunofluorescence. Middle cerebral artery occlusion (MCAO) was developed in rats as a model of cerebral ischemia-reperfusion. The neuroprotective effect of TSPN was evaluated by neurological scoring, tail suspension test, 2,3,5-triphenyltetrazolium chloride (TTC) and Nissl stainings. Western blot analysis, immunohistochemistry and immunofluorescence were used to measure the changes in the Akt/mammalian target of rapamycin (mTOR) signaling pathway.@*RESULTS@#MTT showed that TSPN (50, 25 and 12.5 µ g/mL) protected cortical neurons after OGD/R treatment (P<0.01 or P<0.05). Flow cytometry and live/dead cell assays indicated that 25 µ g/mL TSPN decreased neuronal apoptosis (P<0.05), and immunofluorescence showed that 25 µ g/mL TSPN restored the dendritic morphology of damaged neurons (P<0.05). Moreover, 12.5 µ g/mL TSPN downregulated the expression of Beclin-1, Cleaved-caspase 3 and LC3B-II/LC3B-I, and upregulated the levels of phosphorylated (p)-Akt and p-mTOR (P<0.01 or P<0.05). In the MCAO model, 50 µ g/mL TSPN improved defective neurological behavior and reduced infarct volume (P<0.05). Moreover, the expression of Beclin-1 and LC3B in cerebral ischemic penumbra was downregulated after 50 µ g/mL TSPN treatment, whereas the p-mTOR level was upregulated (P<0.05 or P<0.01).@*CONCLUSION@#TSPN promoted neuronal survival and protected dendrite integrity after OGD/R and had a potential therapeutic effect by alleviating neurological deficits and reversing neuronal loss. TSPN promoted p-mTOR and inhibited Beclin-1 to alleviate ischemic damage, which may be the mechanism that underlies the neuroprotective activity of TSPN.

Screening of the ubiquitin-proteasome system activators for anti-Alzheimer's disease by the high-content fluorescence imaging system / 中国天然药物

Ubiquitin-proteasome system (UPS) plays an important role in neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). The discovery of UPS activators for anti-neurodegenerative diseases is becoming increasingly important. In this study, we aimed to identify potential UPS activators using the high-throughput screening method with the high-content fluorescence imaging system and validate the neuroprotective effect in the cell models of AD. At first, stable YFP-CL1 HT22 cells were successfully constructed by transfecting the YFP-CL1 plasmid into HT22 cells, together with G418 screening. The degradation activity of the test compounds via UPS was monitored by detecting the YFP fluorescence intensity reflected by the ubiquitin-proteasome degradation signal CL1. By employing the high-content fluorescence imaging system, together with stable YFP-CL1 HT22 cells, the UPS activators were successfully screened from our established TCM library. The representative images were captured and analyzed, and quantification of the YFP fluorescence intensity was performed by flow cytometry. Then, the neuroprotective effect of the UPS activators was investigated in pEGFP-N1-APP (APP), pRK5-EGFP-Tau P301L (Tau P301L), or pRK5-EGFP-Tau (Tau) transiently transfected HT22 cells using fluorescence imaging, flow cytometry, and Western blot. In conclusion, our study established a high-content fluorescence imaging system coupled with stable YFP-CL1 HT22 cells for the high-throughput screening of the UPS activators. Three compounds, namely salvianolic acid A (SAA), salvianolic acid B (SAB), and ellagic acid (EA), were identified to significantly decrease YFP fluorescence intensity, which suggested that these three compounds are UPS activators. The identified UPS activators were demonstrated to clear AD-related proteins, including APP, Tau, and Tau P301L. Therefore, these findings provide a novel insight into the discovery and development of anti-AD drugs.