Neuroprotective Effect of Sterculia setigera Leaves Hydroethanolic Extract.

Plants are a valuable source of information for pharmacological research and new drug discovery. The present study aimed to evaluate the neuroprotective potential of the leaves of the medicinal plant Sterculia setigera. In vitro, the effect of Sterculia setigera leaves dry hydroethanolic extract (SSE) was tested on cultured cerebellar granule neurons (CGN) survival when exposed to hydrogen peroxide (H2O2) or 6-hydroxydopamine (6-OHDA), using the viability probe fluorescein diacetate (FDA), a lactate dehydrogenase (LDH) activity assay, an immunocytochemical staining against Gap 43, and the quantification of the expression of genes involved in apoptosis, necrosis, or oxidative stress. In vivo, the effect of intraperitoneal (ip) injection of SSE was assessed on the developing brain of 8-day-old Wistar rats exposed to ethanol neurotoxicity by measuring caspase-3 activity on cerebellum homogenates, the expression of some genes in tissue extracts, the thickness of cerebellar cortical layers and motor coordination. In vitro, SSE protected CGN against H2O2 and 6-OHDA-induced cell death at a dose of 10 µg/mL, inhibited the expression of genes Casp3 and Bad, and upregulated the expression of Cat and Gpx7. In vivo, SSE significantly blocked the deleterious effect of ethanol by reducing the activity of caspase-3, inhibiting the expression of Bax and Tp53, preventing the reduction of the thickness of the internal granule cell layer of the cerebellar cortex, and restoring motor functions. Sterculia setigera exerts neuroactive functions as claimed by traditional medicine and should be a good candidate for the development of a neuroprotective treatment against neurodegenerative diseases.

[Lianmei Qiwu Decoction relieves diabetic cardiac autonomic neuropathy by regulating AMPK/TrkA/TRPM7 signaling pathway].

This study investigated the effect of Lianmei Qiwu Decoction(LMQWD) on the improvement of cardiac autonomic nerve remodeling in the diabetic rat model induced by the high-fat diet and explored the underlying mechanism of LMQWD through the AMP-activated protein kinase(AMPK)/tropomyosin receptor kinase A(TrkA)/transient receptor potential melastatin 7(TRPM7) signaling pathway. The diabetic rats were randomly divided into a model group, an LMQWD group, an AMPK agonist group, an unloaded TRPM7 adenovirus group(TRPM7-N), an overexpressed TRPM7 adenovirus group(TRPM7), an LMQWD + unloaded TRPM7 adenovirus group(LMQWD+TRPM7-N), an LMQWD + overexpressed TRPM7 adenovirus group(LMQWD+TRPM7), and a TRPM7 channel inhibitor group(TRPM7 inhibitor). After four weeks of treatment, programmed electrical stimulation(PES) was employed to detect the arrhythmia susceptibility of rats. The myocardial cell structure and myocardial tissue fibrosis of myocardial and ganglion samples in diabetic rats were observed by hematoxylin-eosin(HE) staining and Masson staining. The immunohistochemistry, immunofluorescence, real-time quantitative polymerase chain reaction(RT-PCR), and Western blot were adopted to detect the distribution and expression of TRPM7, tyrosine hydroxylase(TH), choline acetyltransferase(ChAT), growth associated protein-43(GAP-43), nerve growth factor(NGF), p-AMPK/AMPK, and other genes and related neural markers. The results showed that LMQWD could significantly reduce the arrhythmia susceptibility and the degree of fibrosis in myocardial tissues, decrease the levels of TH, ChAT, and GAP-43 in the myocardium and ganglion, increase NGF, inhibit the expression of TRPM7, and up-regulate p-AMPK/AMPK and p-TrkA/TrkA levels. This study indicated that LMQWD could attenuate cardiac autonomic nerve remodeling in the diabetic state, and its mechanism was associated with the activation of AMPK, further phosphorylation of TrkA, and inhibition of TRPM7 expression.

Polygoni Multiflori Radix Praeparata and Acori Tatarinowii Rhizoma ameliorate scopolamine-induced cognitive impairment by regulating the cholinergic and synaptic associated proteins.

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Polygoni Multiflori Radix Praeparata (PMRP) and Acori Tatarinowii Rhizoma (ATR) is often used in traditional Chinese medicine to prevent and treat Alzheimer's disease (AD). However, it is not clear whether the effects and mechanisms of the decoction prepared by traditional decocting method (PA) is different from that prepared by modern decocting method (P + A). AIM OF THE STUDY: The present study aimed to investigate the differences in the protective effects of PA and P + A on scopolamine induced cognitive impairment, and to explore its potential mechanism. MATERIALS AND METHODS: To assess the protective effect of PA and P + A on cognitive dysfunction, the mice were orally administrated with PA (1.56, 6.24 g kg-1•day-1) and P + A (1.56, 6.24 g kg-1•day-1) for 26 days before co-treatment with scopolamine (4 mg kg-1•day-1, i.p.). The learning and memory abilities of mice were examined by Morris water maze test, and the expressions of proteins related to cholinergic system and synaptic function were detected by the methods of ELISA, real-time PCR and Western blotting. Then, molecular docking technique was used to verify the effect of active compounds in plasma after PA administration on Acetylcholinesterase (AChE) protein. Finally, the Ellman method was used to evaluate the effects of different concentrations of PA, P + A (1 µg/mL-100 mg/mL) and the compounds (1-100 µM) on AChE activity in vitro. RESULTS: On one hand, in the scopolamine-induced cognitive impairment mouse model, both of PA and P + A could improve the cognitive impairment, while the effect of PA on cognitive amelioration was better than that of P + A. Moreover, PA regulated the cholinergic and synaptic functions by enhancing the concentration of acetylcholine (ACh), the mRNA levels of CHT1, Syn, GAP-43 and PSD-95, and the related proteins (CHT1, VACHT, Syn, GAP-43 and PSD-95), and significantly inhibiting the expression of AChE protein. Meanwhile, P + A only up-regulated the mRNA levels of GAP-43 and PSD-95, increased the expressions of CHT1, VACHT, Syn, GAP-43 and PSD-95 proteins, and inhibited the expression of AChE protein. On the other hand, the in vitro study showed that some compounds including emodin-8-o-ß-d-Glucopyranoside, THSG and α-Asarone inhibited AChE protein activity with the IC50 values 3.65 µM, 5.42 µM and 9.43 µM, respectively. CONCLUSIONS: These findings demonstrate that both of PA and P + A can ameliorate the cognitive deficits by enhancing cholinergic and synaptic related proteins, while PA has the stronger improvement effect on the cholinergic function, which may be attributed to the compounds including THSG, emodin, emodin-8-O-ß-D-glucopyranoside and α-asarone. The present study indicated that PA has more therapeutic potential in the treatment of neurodegenerative diseases such as AD. The results provide the experimental basis for the clinical use of PA.

Investigation of effects of quercetin and low-level laser therapy in cisplatin-induced in vitro peripheral neuropathy model.

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the dose-dependent side effects of cisplatin. The loss of sensory neurons is observed in CIPN. There are many methods to minimalize CIPN symptoms such as pharmacological agents and photobiostimulation but the mechanisms of these methods are unclear. Our study is aimed at determining the effects of quercetin and low-level laser therapy (LLLT) in undifferentiated and nerve growth factor-differentiated PC12 cells in cisplatin-induced peripheral neuropathy. PC12 cells with cisplatin were co-treated with quercetin and LLLT (diode pumped all-solid-state laser, 670 nm, output 500 mW, and the laser beam surface area was 1.96 cm2). The effects of quercetin and LLLT on GAP-43 and Synapsin I expressions were analyzed by real-time PCR, cell viability was assessed by MTT assay, Annexin and dead assay measured the induction of apoptosis, the alterations in mitopotential were assessed by mitopotential assay, and lactate dehydrogenase activity in cells was analyzed. All experiment data were analyzed by the Tukey test and applied as a post hoc test, and statistical evaluation was made. Our results indicated that cisplatin increased apoptosis (24,210 ± 2189, 46,504 ± 8246) cells, mitochondrial dysfunction (44,312 ± 0.751, 68,788 ± 1271), and LDH activity (62,821 ± 8245, 87,838 ± 8116). Furthermore, it decreased cell viability (42,447 ± 1780, 36,140 ± 3682) and inhibited GAP-43 and Synapsin I genes in undifferentiated and differentiated PC12 cells. However, apoptosis, the alterations in mitopotential, and lactate dehydrogenase activity decreased by applications of quercetin and LLLT. It has been recommended that quercetin and low-level laser therapy roles on cisplatin-induced peripheral neuropathy should be investigated in vivo, and the relationship between quercetin and low-level laser therapy should be molecular.

Taurine Ameliorates Oxidative Stress in Spinal Cords of Diabetic Rats via Keap1-Nrf2 Signaling.

Hyperglycemia associated with diabetes mellitus (DM) causes oxidative stress, which is involved in the onset and development of diabetic neuropathy. Taurine, a powerful antioxidant, is an effective inhibitor of oxidative stress. The present experiment was conducted to explore the effect of taurine treatment on alterations in body weight, blood glucose, oxidative stress, and Keap1-Nrf2 signaling in the spinal cords of DM rats. The DM rat model was established by STZ injection, and taurine was administered in the drinking water. Body weight and blood glucose were recorded during the experiment. The expression of Gap-43 and MBP proteins was examined by Western blot. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were examined as indicators of oxidative stress. The expression of Keap1, Nrf2, and HO-1 gene was examined by real-time PCR. The results showed that compared with the control group, the body weight was decreased, blood glucose was increased, and both Gap-43 and MBP expression were decreased in DM rats, which were all remarkably reversed by taurine treatment. Oxidative stress, as reflected by lower SOD activity and higher MDA concentration, was inhibited in taurine-treated DM rats. Supplemental taurine also downregulated the mRNA level of Keap1, while upregulating Nrf2 and HO-1 mRNA levels. These results showed that taurine inhibits oxidative stress in the spinal cords of DM rats, an effect that might involve the regulation of Keap1-Nrf2 signaling.

Resistance training and Urtica dioica increase neurotrophin levels and improve cognitive function by increasing age in the hippocampus of rats.

INTRODUCTION: Inflammation and oxidative stress are two major factors in accelerating brain aging. Consumption of some traditional herbs with antioxidant and anti-inflammatory properties such as Urtica dioica extract (Ud) and resistance training (RT) may be effective in controlling premature aging and memory impairment. Therefore, we hypothesized that the combined effect of RT and Ud might play an essential role in preventing memory disorders and hippocampal tissue changes caused by increasing age in rats. METHODS: 28 male Wistar rats (24-week) were divided into 4-groups (n = 7): control (C), Ud, RT, and Ud+RT. RT groups were trained for five weeks, and Ud extract in the 0.0166 w/v concentration (50 mg/kg, oral/daily) was administered. We also examined the effects of RT and Ud on the behavioral (memory and learning), histological (the morphological changes in the dentate gyrus), and transcript aspects of hippocampal tissue. RESULTS: Aging led to karyopyknosis in the hippocampal tissue, which was alleviated by RT and Ud supplementation. RT and Ud were accompanied by increased GPx, GSH, GAP-43, and decreased CAP-1 levels in the hippocampus. Moreover, RT and Ud led to increased NGF, BDNF, and GAP-43 levels, decreased MDA, and protection of hippocampal tissue from karyopyknosis, which was associated with cognitive improvement. However, these interventions had no significant effect on the hippocampal levels of IL-1ß, SOD, and CAT. CONCLUSIONS: These findings suggest that increasing age decreases hippocampal NGF, BDNF, and GAP-43 levels and impairs cognition, which may be reversed by regular RT and Ud extract.

Highly oxygenated chemical constitutes and rearranged derivatives with neurotrophic activity from Ganoderma cochlear.

ETHNOPHARMACOLOGICAL RELEVANCE: The morphological characteristics of Ganoderma cochlear (Blume & T. Nees) Bres were identical to G. sinsense J.D. Zhao, L.W. Hsu & X.Q. Zhang, however, with the fungus stipe lying in the back of the pileus. Fruiting bodies and spores of G. cochear have been traditionally used for smoothing, sleeping improvement, memory impairment, anti-aging, and prolonging life. Alzheimer's disease (AD) is a chromic progressive neurodegenerative disorder associated with loss of memory and cognition. Hallmarks of AD include aging, amyloid-ß plaques, neurofibrillary tangles, neuron loss, neuronal degeneration, network disruption, cognitive dysfunction, inflammation and oxidation stress. In this study, norlanostanoids from G. cochear are identified as potential neurotrophic chemists related to the memory impairment usage to slow down pathogenetic process and restore neural circuits for AD. AIM OF STUDY: Chemical and biological investigations in this study uncovered the potential constituents related to the traditional usage of G. cochlear. MATERIALS AND METHODS: The extract of the mushrooms was purified using various column chromatography techniques and high-performance liquid chromatography (HPLC). The structures of the isolates were elucidated by combination of spectral, and single crystal X-ray diffraction analysis. The neurotrophic activity was evaluated by the differentiation state of PC12 cells, and the dose-dependent and time-dependant expression of growth-associated protein (GAP-43) was analyzed by western blotting. RESULTS: Ganorbifates J-T (1-11), eleven previously undescribed triterpenoids together with five known trinorlanostanoids (12-16) were isolated from the fruiting bodies of G. Cochlear. Among them, ganorbifates N-O (5-6) had a demethylation at C-28 compared to the classic skeleton of 3,4-seco-25,26,27-trinorlanostanoids to form a new group of 3,4-seco-25,26,27,28-tetranorlanostanoids. Based on this, a novel skeleton of ganorbifate M (4) was further established by the arrangement of C-29 from C-4 to C-7. A plausible biosynthetic pathway of compounds 4-6 was proposed. Eight of the sixteen isolates showed neurotrophic activity with the concentration of 10 µM. Furthermore, compound 15 exhibited a dose-dependent neurogenic activity, and also strengthened the expression of the growth-associated protein (GAP-43) in NGF-induced PC-12 cells, whereas 11 showed an inhibitory effect at higher concentration. CONCLUSION: These results demonstrated that 3,4-seco-norlanostanoids had reliable potential in promoting the outgrowth of PC-12 cells and could be used in the prevention and treatment of Alzheimer's disease, which is consist with the beneficial effects of G. Cochlear.

Pretreatment with combined low-level laser therapy and methylene blue improves learning and memory in sleep-deprived mice.

Low-level laser therapy (LLLT) and methylene blue (MB) were proved to have neuroprotective effects. In this study, we evaluated the preventive effects of LLLT and MB alone and in combination to examine their efficacy against sleep deprivation (SD)-induced cognitive impairment. Sixty Balb/c male mice were randomly divided into five groups as follows: wide platform (WP), SD, LLLT, MB, LMB (treatment with both LLLT and MB). Daily MB (0.5 mg/kg) was injected for ten consecutive days. An 810-nm, 10-Hz pulsed laser was used in LLLT every other day. We used the T-maze test, social interaction test (SIT), and shuttle box to assess learning and memory and PSD-95, GAP-43, and synaptophysin (SYN) markers to examine synaptic proteins levels in the hippocampus. Our results showed that SD decreased alternation rate in the T-maze test, sociability and social novelty in SIT, and memory index in the shuttle box. Single treatments were not able to reverse these in most of the behavioral parameters. However, behavioral tests showed a significant difference between combined therapy and the SD group. The levels of synaptic plasticity markers were also significantly reduced after SD. There was a significant difference between the MB group and SD animals in GAP-43 and SYN biomarkers. Combination treatment with LLLT and MB also increased GAP-43, PSD-95, and SYN compared to the SD group. We found that the combined use of LLLT and MB pretreatment is more effective in protecting SD-induced cognitive impairment, which may be imparted via modulation of synaptic proteins.

Regulation of Neurogenesis and Neuronal Differentiation by Natural Compounds.

Neuronal damage or degeneration is the main feature of neurological diseases. Regulation of neurogenesis and neuronal differentiation is important in developing therapies to promote neuronal regeneration or synaptic network reconstruction. Neurogenesis is a multistage process in which neurons are generated and integrated into existing neuronal circuits. Neuronal differentiation is extremely complex because it can occur in different cell types and can be caused by a variety of inducers. Recently, natural compounds that induce neurogenesis and neuronal differentiation have attracted extensive attention. In this paper, the potential neural induction effects of medicinal plant-derived natural compounds on neural stem/progenitor cells (NS/PCs), the cultured neuronal cells, and mesenchymal stem cells (MSCs) are reviewed. The natural compounds that are efficacious in inducing neurogenesis and neuronal differentiation include phenolic acids, polyphenols, flavonoids, glucosides, alkaloids, terpenoids, quinones, coumarins, and others. They exert neural induction effects by regulating signal factors and cellspecific genes involved in the process of neurogenesis and neuronal differentiation, including specific proteins (ß-tubulin III, MAP-2, tau, nestin, neurofilaments, GFAP, GAP-43, NSE), related genes and proteins (STAT3, Hes1, Mash1, NeuroD1, notch, cyclin D1, SIRT1, Reggie-1), transcription factors (CREB, Nkx-2.5, Ngn1), neurotrophins (BDNF, NGF, NT-3), and signaling pathways (JAK/STAT, Wnt/ß-catenin, MAPK, PI3K/Akt, GSK-3ß/ß-catenin, Ca2+/CaMKII/ATF1, Nrf2/HO-1, BMP).The natural compounds with neural induction effects are of great value for neuronal regenerative medicine and provide promising prevention and treatment strategies for neurological diseases.

[Effect of acupuncture serum on expression of microtubule associated protein-2 and nerve growth associated protein-43 in Mg2+-free-cultured hippocampal neurons of neonatal rats].

OBJECTIVE: To observe the effect of acupuncture serum on the expression of microtubule associated protein-2 (MAP-2) and nerve growth associated protein-43 (GAP-43) in cultured hippocampal neurons of convulsive rats. METHODS: The acute convulsion model was induced by intraperitoneal injection of pentylenetetrazol in SD rats who were then randomized into model group and acupuncture group. Rats of the acupuncture group received manual acupuncture stimulation of "Baihui" (GV20) and "Dazhui" (GV14) for 30 min, once daily for 7 days. Then, the blood samples taken from the abdominal aorta of rats in the convulsion model and acupuncture groups were processed into serum samples, i.e. non-acupuncture serum and acupuncture se-rum. The primary-cultured hippocampal neurons of fetal rats were cultured for 10 days and then divided into normal extracellular fluid (normal) group, magnesium (Mg2+) free extracellular fluid group, acupuncture serum group and non-acupuncture serum group. At the 10th day, the neurons in the normal group were cultured continuously in extracellular fluid for 3 h, and then cultured in DMEM/F12(1∶1) medium (planting fluid); neurons in the Mg2+ free group were cultured in magnesium-free fluid medium to induce epileptic-like discharge; neurons in the acupuncture serum group were cultured in the mixed medium of planting fluid and 10% acupuncture serum; and neurons in the non-acupuncture serum were cultured in the mixed culture medium of planting fluid and non-acupuncture serum (10%). At last, these neurons in the above-mentioned groups were cultured in the magnesium-free extracellular fluid continuously for 2, 12 and 48 h, respectively, followed by detecting the expression levels of MAP-2 and GAP-43 proteins at the 3 time points by using immunofluorescence and Western blot, separately. RESULTS: The rate of MAP-2 positive cells and protein expression at 2, 12 and 48 h, and the rate of GAP-43 positive cells and protein expression at 12 and 48 h in the hippocampal neurons were significantly down-regulated in the Mg2+ free group in contrast to the normal group (P<0.05，P<0.01). Compared to the Mg2+ free group, the rates of MAP-2 and GAP-43 positive cells and protein expression at 2, 12 and 48 h were considerably up-regulated in the acupuncture serum group (P<0.05，P<0.01), but not in the non-acupuncture serum group (P>0.05). CONCLUSION: Acupuncture serum can significantly up-regulate the expression of MAP-2 and GAP-43 proteins in hip-pocampal neurons, which may play a positive role in improving synaptic plasticity and neuronal damage in convulsion rats.

Lutein/zeaxanthin isomers regulate neurotrophic factors and synaptic plasticity in trained rats

Background/aim: This study was conducted to elucidate the effects of lutein/zeaxanthin isomers (L/Zi) on lipid metabolism, oxidative stress, NF-κB/Nrf2 pathways, and synaptic plasticity proteins in trained rats. Materials and methods: Wistar rats were distributed into four groups: 1) control, 2) L/Zi: rats received L/Zi at the dose of 100 mg/kg by oral gavage, 3) exercise, 4) exercise+L/Zi: rats exercised and received L/Zi (100 mg/kg) by oral gavage. The duration of the study was eight weeks. Results: Exercise combined with L/Zi reduced lipid peroxidation and improved antioxidant enzyme activities of muscle and cerebral cortex in rats (p < 0.001). In the Exercise + L/Zi group, muscle and cerebral cortex Nrf2 and HO-1 levels increased, while NF-κB levels decreased (p <0.001). Also, L/Zi improved BDNF, synapsin I, SYP, and GAP-43 levels of the cerebral cortex of trained rats (p < 0.001). The highest levels of BDNF, synapsin SYP, and GAP-43 in the cerebral cortex were determined in the Exercise+L/Zi group. Conclusion: These results suggested that exercise combined with L/Zi supplementation might be effective to reduce neurodegeneration via improving neurotrophic factors and synaptic proteins, and oxidative capacity in the cerebral cortex.

[Effect of moxibustion on expression of GAP-43 in sciatic nerve trunk and ventral horn of spinal cord of rats with primary sciatica and its nerve repair function].

OBJECTIVE: To observe the effect of moxibustion at "Huantiao" (GB 30) on the expression of growth-associated protein-43 (GAP-43) in the sciatic nerve trunk and ventral horn of spinal cord (L4-L6) in rats with primary sciatica, and to explore the mechanism of moxibustion in improving primary sciatica. METHODS: A total of 48 healthy male SD rats were randomly divided into a normal group, a sham operation group, a model group and a moxibustion group, 12 rats in each group. The rat model of primary sciatic pain was established by chronic constriction injury (CCI) of the sciatic nerve in the model group and the moxibustion group. On the 8th day of the experiment, moxibustion was adopted at "Huantiao" (GB 30) in the moxibustion group for 5-10 min, once a day for 14 consecutive days. Sciatic nerve function index (SFI) was measured and compared in each group at day 1, 7, 14 and 21. On the 21st day of the experiment, HE staining was used to observe the morphology of ventral horn of rat spinal cord and sciatic nerve trunk. Immunohistochemical method and real-time PCR were used to detect mRNA and protein expressions of GAP-43 in the spinal cord and sciatic nerve trunk of rats. RESULTS: On day 7, 14 and 21, there was no statistical difference in SFI between the sham operation group and the normal group (P>0.05); compared with the sham operation group on day 7, 14 and 21, the SFI of the model group was reduced (P<0.01); compared with the model group on day 14 and 21, SFI in the moxibustion group was increased (P<0.01). In the normal group and the sham operation group, neuronal cells were in order in the ventral horn of the spinal cord, nissl bodies were spaced regularly, the myelin sheath structure of sciatic nerve axon was clearly visible. In the model group, neuronal cells were deformed and ruptured in the ventral horn of the spinal cord, the number of nissl bodies was less, and the demyelination of sciatic axons appeared. In the moxibustion group, neuronal cells were found in the ventral horn of spinal cord, and the number of nissl bodies was increased, and less demyelinating changes of axons appeared in sciatic nerve. Compared with the normal group, the expressions of GAP-43 mRNA and GAP-43 protein in the sciatic nerve trunk and GAP-43 protein in the ventral horn of spinal cord were increased in the sham operation group (P<0.01). Compared with the sham operation group, the expression of GAP-43 mRNA and GAP-43 protein in the spinal cord and sciatic nerve trunk of rats in the model group was increased. Compared with the model group, the expression of GAP-43 mRNA and GAP-43 protein in the spinal cord and sciatic nerve trunk of rats in the moxibustion group was increased (P<0.01). CONCLUSION: Moxibustion at "Huantiao" (GB 30) could improve the sciatic nerve function in rats with primary sciatica and its mechanism may be related to improving the expression of GAP-43 and enhancing the self-repair ability of the sciatic nerve after injury.

Achyranthes bidentata polypeptide k enhances the survival, growth and axonal regeneration of spinal cord motor neurons in vitro.

Achyranthes bidentata polypeptide k (ABPPk), a powerful active component from a traditional Chinese medicinal herb-Achyranthes bidentata Bl., has exhibited promising neuroprotective activity due to its multiple-targeting capability. However, the effect of ABPPk on the survival, growth and axonal regeneration of spinal cord motor neurons remains unclear. Here, a modified method, which is more optimized for embryonic cells in ambient carbon dioxide levels, was used for acquisition of rat embryonic spinal cord motor neurons with high survival and purity. ABPPk concentration-dependently enhanced the neuronal viability and promoted the neurite outgrowth. Co-culture of motor neurons and skeletal myocytes model indicated that ABPPk enhanced the neuromuscular junction development and maturation. A microfluidic axotomy model was further established for the axonal disconnection, and ABPPk significantly accelerated the axonal regeneration of motor neurons. Furthermore, we demonstrated that the upregulation of three neurofilament protein subunits in motor neurons might be relevant to the mechanisms of the growth-promoting effect of ABPPk. Our findings provide an experimental and theoretical basis for the development of ABPPk as a potential application in the development of treatment strategy for nerve injury diseases.

Effect of moxibustion on expression of GAP-43 in sciatic nerve trunk and ventral horn of spinal cord of rats with primary sciatica and its nerve repair function / 中国针灸

OBJECTIVE@#To observe the effect of moxibustion at "Huantiao" (GB 30) on the expression of growth-associated protein-43 (GAP-43) in the sciatic nerve trunk and ventral horn of spinal cord (L@*METHODS@#A total of 48 healthy male SD rats were randomly divided into a normal group, a sham operation group, a model group and a moxibustion group, 12 rats in each group. The rat model of primary sciatic pain was established by chronic constriction injury (CCI) of the sciatic nerve in the model group and the moxibustion group. On the 8th day of the experiment, moxibustion was adopted at "Huantiao" (GB 30) in the moxibustion group for 5-10 min, once a day for 14 consecutive days. Sciatic nerve function index (SFI) was measured and compared in each group at day 1, 7, 14 and 21. On the 21st day of the experiment, HE staining was used to observe the morphology of ventral horn of rat spinal cord and sciatic nerve trunk. Immunohistochemical method and real-time PCR were used to detect mRNA and protein expressions of GAP-43 in the spinal cord and sciatic nerve trunk of rats.@*RESULTS@#On day 7, 14 and 21, there was no statistical difference in SFI between the sham operation group and the normal group (@*CONCLUSION@#Moxibustion at "Huantiao" (GB 30) could improve the sciatic nerve function in rats with primary sciatica and its mechanism may be related to improving the expression of GAP-43 and enhancing the self-repair ability of the sciatic nerve after injury.

SiNiSan ameliorates depression-like behavior in rats by enhancing synaptic plasticity via the CaSR-PKC-ERK signaling pathway.

BACKGROUND: Adverse stress in early life negatively influences psychiatric health by increasing the risk of developing depression and suicide in adulthood. Clinical antidepressants, such as fluoxetine, exhibit unsatisfactory results due to their low efficacy or intolerable side effects. SiNiSan (SNS), a traditional Chinese herbal formula, has been proven to have affirmatory antidepressive effects. However, the underlying mechanism remains poorly understood. Therefore, this study aimed to explore the impact and molecular mechanism of SNS treatment in rats exposed to neonatal maternal separation (MS)-combined young-adult chronic unpredictable mild stress (CUMS). METHOD: Seventy-two neonatal male Sprague-Dawley rats were randomly divided into six groups of 12 rats each: control + ddH2O, model + ddH2O, positive (fluoxetine: 5 mg/kg), SNS-low dose (2.5 g/kg), SNS-medium dose (5 g/kg), and SNS-high dose (10 g/kg). Behavioral tests included sucrose preference test, open-field test, and forced swimming test. Calcium sensitive receptor (CaSR), protein kinase C (PKC), ERK1/2, and synapse-associated proteins (PSD-95, GAP-43, and synaptophysin [Syn]) in the hippocampus (HIP) and prefrontal cortex (PFC) were assayed using Western blot. CaSR and Syn protein expression was measured by immunohistochemistry. RESULTS: MS-combined CUMS rats exhibited depression-like behavior. SNS exerted antidepressant effects on stress-induced depression-like behavior. The levels of CaSR, PKC, and p-ERK1/2 in the HIP and PFC decreased in stressed rats. SNS treatment significantly upregulated the expression of CaSR, PKC, and p-ERK1/2 in the HIP and PFC of adult stressed rats. CONCLUSION: MS-combined CUMS could develop depression-like behavior in adult. SNS exhibited antidepressive effects accompanied by improving synaptic plasticity by activation of the CaSR-PKC-ERK signaling pathway.

Corticotropin-releasing hormone 1 receptor antagonism attenuates chronic unpredictable mild stress-induced depressive-like behaviors in rats.

Hyperactivity of the hypothalamic-pituitary-adrenal axis and impairment of the central corticotropin-releasing factor system are factors in the pathogenesis of depression. Though several antagonists of the corticotropin-releasing factor 1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between corticotropin-releasing factor 1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of CP154526, a corticotropin-releasing factor 1 receptor blocker, which presented some signs of depression. Our results revealed that CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment notably improved the sucrose consumption, produced anti-depressive-like behavior in open-field test, as well as immobility time in forced swimming test. The levels of interleukin-6, interleukin-1ß, tumor necrosis factor-α, and corticotropin-releasing hormone concentration in the serum were inhibited effectively by CP154526 or fluoxetine administration. Real-time quantitative PCR and western blot analysis showed the upregulated levels of brain-derived neurotrophic factor and growth associated protein 43 (GAP43) in the hypothalamus of the rats exposed to chronic unpredictable mild stress (CUMS), while different degrees of downregulation in their expression were detected after CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment, respectively. Thus, our data demonstrated that CP154526 exhibited antidepressant effect in CUMS rats, which might be mediated by decreasing the brain-derived neurotrophic factor and GAP43 expression in the hypothalamus.

Cell Chromatography-Based Screening of the Active Components in Buyang Huanwu Decoction Promoting Axonal Regeneration.

Buyang Huanwu decoction (BHD), a popular formulation prescribed in traditional Chinese medicine (TCM) for the treatment of ischemic stroke, has been reported to have a potential role in promoting axonal regeneration. The purpose of the study was to screen and identify bioactive compounds from BHD using live PC12 cells coupled with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Using this approach, we successfully identified six bioactive components from BHD. These components have protective effects on oxygen-glucose deprivation/reperfusion (OGD/R) injury to PC12 cells. Furthermore, calycosin-7-d-glucoside (CG) and formononetin-7-O-ß-d-glucoside (FG) could upregulate the protein expression of growth-associated protein 43 (GAP-43) and brain-derived neurotrophic factor (BDNF). This study suggests that living cells combined with HPLC-MS/MS can be used for the screening of active ingredients in TCMs.

Taurine Promotes Neuritic Growth of Dorsal Root Ganglion Cells Exposed to High Glucose in Vitro.

Diabetic neuropathy (DN) is the most common chronic complication of DM and its major pathological changes show axonal dysfunction, atrophy and loss. However, there are few reports that taurine promotes neurite growth of dorsal root ganglion (DRG) cells. In current study, DRG neurons were exposed to high glucose (HG) with or without taurine. The neurite outgrowth of DRG neurons was observed by fluorescent immunohistochemistry method. Expression of Gap-43, Akt, phosphorylated Akt, mTOR and phosphorylated mTOR was determined by Western blot assay. Our results showed that HG significantly decreased the neurite outgrowth and expression of Gap-43 in DRG neurons. Moreover, phosphorylated levels of Akt and mTOR were downregulated in DRG neurons exposed to HG. On the contrary, taurine supplementation significantly reversed the decreased neurite outgrowth and Gap-43 expression, and the downregulated phosphorylated levels of Akt and mTOR. However, the protective effects of taurine were blocked in the presence of PI3K antagonists LY294002 or Akt antagonists Perifosine. These results indicate that taurine promotes neurite outgrowth of DRG neurons exposed to HG via activating Akt/mTOR signal pathway.

Fastigial nucleus electrostimulation promotes axonal regeneration after experimental stroke via cAMP/PKA pathway.

Axon regeneration after cerebral ischemia in mammals is inadequate to restore function, illustrating the need to design better strategies for improving outcomes. Improvement of axon regeneration has been achieved through fastigial nucleus electrostimulation (FNS) in animal researches. However, the mechanisms underlying this neuroprotection remain poorly understood. Increasing the levels of the second messenger cyclic AMP (cAMP) enhances axon regeneration, making it an excellent candidate molecule that has therapeutic potential. In the present study, we examined the expression of cAMP signaling in ischemic brain tissues following focal cerebral ischemia. Adult rats were subjected to ischemia induced by middle cerebral artery occlusion (MCAO). A dipolar electrode was placed into the cerebellum to stimulate the cerebellar fastigial nucleus for 1 h after ischemia. Neurological deficits and the expressions of cAMP, PKA (protein kinase A) and ROCK (Rho-kinase) were determined. Axonal regeneration was measured by upregulation of growth-associated protein 43 (GAP43). The data indicated that FNS significantly enhanced axonal regeneration and motor function recovery after cerebral ischemia. FNS also significantly increased cAMP and PKA levels after ischemic brain injury. All the beneficial effects of FNS were blocked by Rp-cAMP, an antagonist of PKA. Our research suggested that the axonal regeneration conferred by FNS was likely achieved via the regulation of cAMP/PKA pathway.

Amygdala stimulation promotes recovery of behavioral performance in a spatial memory task and increases GAP-43 and MAP-2 in the hippocampus and prefrontal cortex of male rats.

The relationships between affective and cognitive processes are an important issue of present neuroscience. The amygdala, the hippocampus and the prefrontal cortex appear as main players in these mechanisms. We have shown that post-training electrical stimulation of the basolateral amygdala (BLA) speeds the acquisition of a motor skill, and produces a recovery in behavioral performance related to spatial memory in fimbria-fornix (FF) lesioned animals. BLA electrical stimulation rises bdnf RNA expression, BDNF protein levels, and arc RNA expression in the hippocampus. In the present paper we have measured the levels of one presynaptic protein (GAP-43) and one postsynaptic protein (MAP-2) both involved in synaptogenesis to assess whether structural neuroplastic mechanisms are involved in the memory enhancing effects of BLA stimulation. A single train of BLA stimulation produced in healthy animals an increase in the levels of GAP-43 and MAP-2 that lasted days in the hippocampus and the prefrontal cortex. In FF-lesioned rats, daily post-training stimulation of the BLA ameliorates the memory deficit of the animals and induces an increase in the level of both proteins. These results support the hypothesis that the effects of amygdala stimulation on memory recovery are sustained by an enhanced formation of new synapses.