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Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, and the effect of NF-κB activation on the protection of Parkinson’s disease by Isoflavone (I). Methods: PC12 cells were used to establish the cell model of Parkinson’s disease, and are divided into five groups: control group; MPP+ group; I (Isoflavone) + MPP+ group; I group; SN-50 + MPP+ group. The content of NF-κB in PC12 cells was determined by immunocytochemistry; The viability of PC12 cells after treated with cell-permeable NF-κB inhibitor SN-50 and cell viability were measured by MTT assay; the expression levels of NF-κB p65 in cytoplasm and nuclear fractions were evaluated by western blot analysis; the mRNA expression of NF-κB p65 was analyzed by in situ hybridization (ISH). Results: Compared with the control group, the protein of NF-κB p65 both in cytoplasm and in nuclei was significantly higher than in I + MPP+ and MPP+ groups; similarly, the mRNA expression level of NF-κB p65 gene was also significantly higher; moreover, the protein expression of NF-κB p65 was much lower in I group (P + group, the protein of NF-κB p65 was significantly lower in I + MPP+ group, the mRNA expression level of NF-κB p65 gene was also significantly lower, and the protein expression level of NF-κB p65 was much lower in I + MPP+ group (P + group (P > 0.05). Conclusion: NF-κB activation is essential to MPP+-induced apoptosis in PC12 cells; but Isoflavone can inhibit the cell damage to some extent to execute its protective function, which may be involved in nigral neurodegeneration in patients with Parkinson’s disease.

To investigate the effects of salvianolic acid A (SAA) on cardiomyocyte apoptosis and mitochondrial dysfunction in response to hypoxia/reoxygenation (H/R) injury and to determine whether the Akt signaling pathway might play a role. An in vitro model of H/R injury was used to study outcomes on primary cultured neonatal rat cardiomyocytes. The cardiomyocytes were treated with 12.5, 25, 50 μg/mL SAA at the beginning of hypoxia and reoxygenation, respectively. Adenosine triphospate (ATP) and reactive oxygen species (ROS) levels were assayed. Cell apoptosis was evaluated by flow cytometry and the expression of cleaved-caspase 3, Bax and Bcl-2 were detected by Western blotting. The effects of SAA on mitochondrial dysfunction were examined by determining the mitochondrial membrane potential (△Ψm) and mitochondrial permeability transition pore (mPTP), followed by the phosphorylation of Akt (p-Akt) and GSK-3β (p-GSK-3β), which were measured by Western blotting. SAA significantly preserved ATP levels and reduced ROS production. Importantly, SAA markedly reduced the number of apoptotic cells and decreased cleaved-caspase 3 expression levels, while also reducing the ratio of Bax/Bcl-2. Furthermore, SAA prevented the loss of △Ψm and inhibited the activation of mPTP. Western blotting experiments further revealed that SAA significantly increased the expression of p-Akt and p-GSK-3β, and the increase in p-GSK-3β expression was attenuated after inhibition of the Akt signaling pathway with LY294002. SAA has a protective effect on cardiomyocyte H/R injury; the underlying mechanism may be related to the preservation of mitochondrial function and the activation of the Akt/GSK-3β signaling pathway.

The aim of the present study was to investigate the effect of Scutellaria baicalensis stem-leaf total flavonoid (SSTF) on the dopaminergic neurons in the substantia nigra in a mouse model of Parkinson's disease (PD). The mouse model was established by intravenous injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). SSTF (5 mg/kg) was administered to the mice before or after MPTP injection, and the effects of SSTF on the behavior of the mice and the dopaminergic neurons in the substantia nigra were assessed. In addition, the level of serum malondialdehyde (MDA) was measured. Following injection of MPTP, the number of dopaminergic neurons in the substantia nigra was decreased and the neurons appeared atrophic. In addition, the level of serum MDA in the MPTP mice increased. The mean behavioral scores and the number of dopaminergic neurons in the SSTF treatment groups were significantly higher than in the MPTP group (P

The study has investigated the effect of isoflavone attenuates the caspase-1 and caspase-3 level in cell model of Parkinsonism. The subjects were PC12 cells. They were randomly divided into six groups: control, MPP+(250 μmol/L), isoflavone (10 μM), isoflavone (10 μM) + MPP+(250 μmol/L), Z-YVAD-CHO (10 nM) + MPP+group, and Z-DEVD-CHO (10 nM) + MPP+group. Cell viability was measured by MTT methods; the content of tyrosine hydroxylase was measured by immunocytochemistry method of avidinbiotin peroxidase complex; apoptosis ratio was measured by flow cytometry. The results showed that cell viability in the MPP+group was lower than in all other five groups. There was no difference in cell viability between isoflavone + MPP+and control group. Optical density of TH positive cells in isoflavone group was higher than in control, isoflavone + MPP+, and MPP+only groups. The apoptosis ratio in the isoflavone + MPP+group and control group and the Z-YVAD-CHO + MPP+and Z-DEVD-CHO + MPP+group was similar, which was lower than in the MPP+group. The lowest apoptosis ratio was found in the isoflavone only group.

To observe the contribution of Borneolum syntheticum to the intervention effect of Liuwei Dihuang Pill (, LDP) on experimental retinal degeneration, and initially investigate the mechanism of Borneolum syntheticum as meridian-lead-in drug.A total of 180 sodium iodateinduced retinital degeneration rats were randomly divided into three groups, including distilled water group, LDP group, and LDP+Borneolum syntheticum (LDP+BS) group. Twenty normal rats were fed regularly without any treatment as normal control. On day 7 and 14 after treatment, histopathological study and transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) test were performed to evaluate the retinopathy. Claudin-5 expression at blood-retina barrier (BRB) was detected by Western blot at different time points from 0.5 to 8 h after gavage.On day 7 and 14 after treatment, the retinal lesion grades were significantly different among the three groups (P0.05). The grade in the LDP+BS group was significantly less than the LDP and distilled water groups (both P0.05), no significant difference was observed between the LDP and distilled water groups (P0.05). The apoptosis rates in the LDP+BS group was significantly less than the distilled water and LDP groups (both P0.05), while there was no significant difference between LDP and distilled water groups (P0.05). Expression of claudin-5 in LDP+BS group was significantly less than the other two groups at 0.5, 1 and 2 h after gavage (P0.05). There was no apparent difference among the three groups at 4 and 8 h after gavage (P0.05).Borneolum syntheticum could strengthen the effect of LDP on experimental retinal degeneration, indicated that Borneolum syntheticum might play the role of meridian-lead-in drug in the formula. The mechanism may be due to Borneolum syntheticum could promote the physiologically openness of bloodretina barrier through transiently affecting the expression of claudin-5.

Previous studies have shown that estrogen may reduce neurological damages in Parkinson's disease but the mechanisms of this protective effect are unclear. This study was designed to investigate the effect of isoflavone, a plant-derived estrogen, on the apoptosis of an in vitro cell model for Parkinson's disease. This cell model was based on 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis in PC12 cells. PC12 cells were divided into four groups: control (vehicle), MPP+ (250 μmol/L) only, isoflavone (10 μM) + MPP+ (250 μmol/L), and isoflavone (10 μM) only group. Bax protein in PC12 cells was measured with Western-blot. The expression of Bax gene was analysed by in situ hybridization assay. The apoptosis ratio in the isoflavone + MPP+ group (30.9%) and the control group (30.7%) was similar (P > 0.05), but it was lower than in the MPP+ group (67.9%, P < 0.05). Optical density in the Bax positive cells in the isoflavone + MPP+ group was lower than in the MPP+ group (0.28 ± 0.03 vs 0.45 ± 0.06, P < 0.05). Bax mRNA in the isoflavone + MPP+ group was lower than in the MPP+ group (0.23 ± 0.02 vs 0.47 ± 0.04, P < 0.01). The Bax protein in the isoflavone + MPP+ group was also lower than in the MPP+ group (89 ± 12 vs 131 ± 19, P < 0.01). In conclusion, soflavone suppressed MPP+-induced apoptosis in PC12 cells. The apoptosis suppression is associated with a decreased level of proapoptotic Bax gene and Bax protein. Further studies are warranted to investigate the clinical effect of isoflavone on Parkinson's disease.

To study the protective effect of rosmarinic acid (Ros A) on the primary cardiomyocyte hypoxia/reoxygenation (H/R) injury.Primary cardiomyocytes of rats were cultured in vitro to establish the H/R injury of cardiomyocytes and observe the changes in the cell viability and LDH leakage. The changes in ATP content and ROS in cardiomyocytes were measured by using chemiluminescence and fluorescent probe technique. The effects of rosmarinic acid on the apoptosis of cardiomyocytes, cleaved-caspase 3, Akt and p-Akt protein expression were further detected by flow cytometry and western blot analysis.According to the experimental results, Ros A at doses of 25, 50, 100 mg x L(-1) could inhibit the decrease in H/R-induced cell viability, LDH leakage and excessive ROS generation, and maintain the ATP level in cells. Ros A at doses of 50, 100 mg x L(-1) could remarkably inhibit the H/R-induced cardiomyocyte apoptosis and down-regulate the expression of cleaved caspase-3. Moreover, Ros A at doses of 100 mg x L(-1) could significantly up-regulate the expression of p-Akt.Ros A has the significant effect in resisting the cardiomyocyte H/R injury, improve cardiomyocyte energy metabolism and reduce cell apoptosis, which is related to the activation of Akt pathway.

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.bionut.2010.09.004. The duplicate article has therefore been withdrawn.

Objectives: The protective effect of estrogen on the neurons in Parkinson’s disease (PD) is unclear. The present study aimed to investigate the effect of estrogen on the apoptosis and dopaminergic function on a cultured cell model of PD. Methods: The PD model was established by addition of 1-methyl-4-phenylpyridinium (MPP+) to PC12 cell culture. Estrogen was added to cell groups with MPP+ (Estrogen+MPP+), and without MPP+ (Estrogen only group). Cell viability, content of tyrosine hydroxylase (TH), apoptosis ratio, expression of apoptosis-suppression protein Bcl-x and apoptosis-acceleration protein IL-1 beta converting enzyme (ICE) were measured. Results: Cell viability in the Estrogen+MPP+ group was similar to the control group but was higher than in the MPP+ group (P < 0.05). The apoptosis ratios in the Estrogen+MPP+ group (33.6%), and the control group (31.3%), were also similar, but it was lower than in the MPP+ group (63.5%, P < 0.05). Concentrations of Bcl-x were higher in the Estrogen+MPP+ group, whereas ICE concentrations were lower than in the MPP+ group (P < 0.05). Conclusions: Estrogen suppresses apoptosis and improves cell viability in MPP+ induced injuries in the PC12 cells. The beneficial effects of estrogen on the PD model are due to the suppression of pro-apoptotic protein ICE, and stimulation of anti-apoptotic protein Bcl-x.