Retracted: Allopregnanolone restores the tyrosine hydroxylase-positive neurons and motor performance in a 6-OHDA-injected mouse model.

AIMS: It has been reported that allopregnanolone (APα) promotes the neurogenesis of the neural progenitor cells (NPCs) in the subventricular zone (SVZ) and prevents the decrease of dopaminergic neurons in 6-hydroxydopamine (6-OHDA)-treated mice by binding to γ-aminobutyric acid A receptor (GABAAR) and then opening voltage-gated L-type Ca2+ channel, but the underlying mechanisms remain elusive. The aim of this study was to explore the possible involvement of GABAAR and calcium/calmodulin-dependent protein kinase II delta 3 (CaMKIIδ3) in this process. METHODS: 6-OHDA-treated mice and primary cultured midbrain cells were administrated with APα and GABAAR antagonist bicuculline (Bic), and the proliferation and differentiation of NPCs, the tyrosine hydroxylase (TH)-positive neurons and their fibers, the expression levels of CaMKIIδ3 and brain-derived neurotrophic factor (BDNF), and motor functions were measured using ELISA, immunohistochemical staining, real-time RT-PCR, Western blot, and behavioral test. RESULTS: Allopregnanolone significantly promoted the phosphorylation of cytoplasmic CaMKIIδ3 and its nuclear translocation by binding to GABAAR, which, in turn, increased the expression levels of BDNF. This may account for the findings that the exogenous APα enhanced the proliferation and differentiation of NPCs, and ameliorated the nigrostriatal system and behavioral performance in 6-OHDA-treated mice. CONCLUSIONS: Allopregnanolone may directly activate GABAAR, which, in turn, enhance the proliferation and differentiation of NPCs via upregulating the expression levels of CaMKIIδ3, and finally contribute to the restoration of dopaminergic neurons in 6-OHDA-treated mice.

[Herbal-cake-partitioned moxibustion of "Shenque" (CV8) has a relative specific effect in relieving abdominal pain and in regulating neuroendocrine-immune network in primary dysmenorrhea rats].

OBJECTIVE: To observe the effect of herbal-cake-partitioned moxibustion (HCPM) of "Shenque" (CV8) and "Daheng" (SP15) on abdominal pain, plasma ß-endorphin (ß-EP), uterine prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) levels, as well as splenetic natural killer cell (NK cell) activity in primary dysmenorrhea (PD) rats, so as to explore the specificity of acupoint function and the underlying mechanisms of moxibustion in relieving dysmenorrhea. METHODS: A total of 40 female rats were randomized into blank control, model, CV8-direct moxibustion, CV8-HCPM and SP15-HCPM groups (n＝8 rats in each). The PD model was established by subcutaneous injection of estradiol benzoate injection (0.2-0.5 mg/rat) for 10 consecutive days and intraperitoneal injection of oxytocin (2 U) 24 h after the last subcutaneous injection. Moxibustion or herbal-cake (composed of Radix Angelicae Sinensis, Rhizoma Chuanxiong, Radix Paeoniae Rubra, Cortex Cinnamomi, etc.)-partitioned moxibustion was applied to CV8, SP15 or umbilicus respectively for 7 moxa-cones every time, once daily for 10 successive days. The rats of the control and model groups were also restrained as those in the moxibustion groups. The writhing times within 30 minutes was recorded and the contents of plasma ß-EP, uterine PGE2 and PGF2α were detected by ELISA, and NK cell activity was detected using MTT. RESULTS: Compared with the control group, the writhing times and the content of PGF2α in the uterus tissue were significantly increased in the model group (P<0.01), while the contents of plasma ß-EP, uterine PGE2 and splenetic NK cell activity were significantly decreased (P<0.01). In comparison with the model group, the writhing times and uterine PGF2α content were obviously down-regulated in the SP15-HCPM, CV8-direct moxibustion and CV8-HCPM groups (P<0.05, P<0.01), and the contents of plasma ß-EP and uterine PGE2, and splenetic NK cell activity were significantly increased (P<0.05, P<0.01). The therapeutic effects of CV8-HCPM group were significantly superior to those of SP15-HCPM and CV8-direct moxibustion groups in lowering writhing times and PGF2α level, and in up-regulating ß-EP, PGE2 (P<0.05, P<0.01). The NK cell activity of CV8-HCPM group was significantly increased compared with that in the SP15-HCPM group(P<0.05). No significant differences were found between the SP15-HCPM and CV8-direct moxibustion groups in the levels of writhing times, plasma ß-EP and uterine PGE2, PGF2α contents and splenetic NK cell activity (P>0.05). CONCLUSION: Moxibustion of both CV8 and SP15 can relieve abdominal pain in PD rats, which may be closely associated with its effect in suppressing PD-induced decrease of plasma ß-EP and uterine PGE2 levels and splenetic NK cell activity and increase of uterine PGF2α. The therapeutic effect of CV8-HCPM is obviously better than that of SP15-HCPM and CV8-direct moxibustion.

[Effect of curcumin on the learning, memory and hippocampal Ca+/CaMK II level in senescence-accelerated mice].

OBJECTIVE: To explore effect of curcumin in different concentrations on learning and memory of senescence-accelerated mice (SAM) and their possible mechanisms. METHODS: Mice were randomly divided into six groups: the SAMR1 normal control group, the SAMP8 model control group, the SAMP8 + solvent (the peanut oil) control group, SAMP8 + low, middle and high dose curcumin groups. Mice were gastrogavage for 25 successive days. On the next day of ending the experiment, changes of learning and memory in mice of each group were observed by Morris water maze. The hippocampal [Ca2+] was determined. Expressions of hippocampal calmodulin-dependent protein kinase II (CaMK II) and Calmodulin (CaM) mRNA were detected using Western blot and reverse transcription polymerase chain reaction (RT-PCR) respectively. RESULTS: The latency to find the hidden platform was remarkably prolonged, the hippocampal [Ca2+]i was markedly increased, the expression of CaMK II in the hippocampal membrane and the level of hippocampal CaM mRNA were significantly reduced in the SAMP8-model control group (P < 0.05, P < 0.01). The latency to find the hidden platform was remarkably shortened in the SAMP8 + middle dose curcumin and the SAMP8 + high dose curcumin groups (P < 0.01). The hippocampal [Ca2+]i was markedly lowered, the expression of CaMK II in the hippocampal membrane and the level of hippocampal CaM mRNA obviously increased in the SAMP8 + low, middle and high dose curcumin groups (P < 0.05, P < 0.01). CONCLUSION: Curcumin could improve learning and memory Ca2+/capacities of SAM by lowering hippocampal [Ca2+] overload, increase the hippocampal CaM mRNA level and CaMK II expression in the hippocampal dose-dependently.

[Effect of Rhizoma curcumae oil on the learning and memory in rats exposed to chronic hypoxia and the possible mechanisms.].

The effect of Rhizoma curcumae oil on the learning and memory in rats exposed to chronic hypoxia and the possible mechanisms were investigated. The rats were divided randomly into 5 groups (14 animals in each group): control, chronic hypoxia, chronic hypoxia with low (5 mg/kg body weight), middle (10 mg/kg body weight) and high (20 mg/kg body weight) concentrations of Rhizoma curcumae oil injection. The animals undergoing chronic hypoxia were exposed to hypoxia in a hypoxic chamber containing 10% O(2) and 5% CO(2) for 10 h/d, lasting 28 d. Morris water maze (MWM) test was used to obtain the scores of leaning and memory. The superoxide dismutase (SOD) activity and malonaldehyde (MDA) content were determined in the serum and hippocampus as well as [Ca(2+)](i) in the hippocampus. The expression of phosphorylated Ca(2+)/calmodulin-dependent protein kinase II (p-CaMKII) in the hippocampus was evaluated by using immunohistochemistry and Western blot. Compared with the control group, the chronic hypoxia group showed the following changes: (1) The escape latency to the hidden platform was remarkably prolonged (P<0.05); (2) The content of MDA and [Ca(2+)](i) were obviously higher, but the activity of SOD and the expression of p-CaMKII were significantly lower (P<0.05, P<0.01). Compared with the chronic hypoxia group, groups with Rhizoma curcumae oil injection had the following changes: (1) The escape latency to the hidden platform was remarkably shorter in 10, 20 mg/kg body weight groups (P<0.05); (2) The content of MDA and [Ca(2+)](i) were markedly decreased in 5, 10, 20 mg/kg body weight groups (P<0.05, P<0.01), but the activity of SOD in the serum and the expression of p-CaMKII were significantly higher in 10, 20 mg/kg body weight groups (P<0.05, P<0.01). The results showed that the capacity of learning and memory was degraded following chronic hypoxia. The decrease in MDA content and [Ca(2+)](i) and (or) the increase in SOD activity and p-CaMKII expression might participate in the enhancing effect on learning and memory induced by Rhizoma curcumae oil.

Changes of learning, memory and levels of CaMKII, CaM mRNA, CREB mRNA in the hippocampus of chronic multiple-stressed rats.

BACKGROUND: The effect of chronic stress on cognitive functions has been one of the hot topic in neuroscience. But there has been much controversy over its mechanism. Such single stressor applied in the past could not simulate complicated living circumstances that people confronted with. The aim of this study was to investigate the effects of chronic multiple-stress on learning and memory as well as on the levels of calcium/calmodulin-dependent protein kinase II (CaMKII), calmodulin (CaM) mRNA, and cAMP-response element binding protein (CREB) mRNA in the hippocampus of rats. METHODS: The rats were divided randomly into stressed and control groups. The stressed group was given chronic multiple-stress for 6 weeks to set up a chronic multiple-stressed model. The rats' performance of spatial learning and memory was tested using Morris Water Maze (MWM) and Y-maze. Meanwhile, the expressions of CaMKII, CaM mRNA and CREB mRNA of rats' hippocampus were detected by immunohistochemistry, Western blot and reverse transcription-polymerase chain reaction (RT-PCR), respectively. In addition, the width of synaptic cleft and the thickness of post-synaptic densities (PSD) were observed in the hippocampal CA3 region of rats by electron microscopy. RESULTS: After exposure to chronic multiple-stress for 6 weeks, the ability of learning and memory of the stressed group was higher than that of the control group (P < 0.05, P < 0.01). The width of synaptic cleft was smaller and the thickness of PSD was larger in the hippocampal CA3 region of the stressed group than in that of the control group (P < 0.01). The CaMK II immunostaining of the stressed group was stronger than that of the control group in the stratum radiatum and oriens of the hippocampal CA1 and CA3, especially in the stratum oriens. Quantitative analysis indicated that the expression of CaMK II, CaM mRNA, and CREB mRNA in the hippocampus of the stressed group was higher than that of the control group (P < 0.05, P < 0.01). CONCLUSIONS: The capacity of learning and memory can be enhanced after chronic multiple-stress. The increased levels of CaMK II, CaM mRNA, and CREB mRNA may contribute to the enhancing effect of chronic multiple-stress on learning and memory.