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

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

Improvement effects of sinapic acid on Aβ42-induced injury of PC 12 cells and the mechanism / 中国药房

OBJECTIVE To s tudy the improvement effects of sinapic acid on Aβ42-induced injury of PC 12 cells and the mechanism. METHODS PC12 cells were divided into five groups ：control group ，model group ，sinapic acid group ，phosphoinositide- 3-kinase（PI3K）inhibitor group and extracellular signal-regulated kinase （ERK）inhibitor group. Each inhibitor group was added with LY 294002 and U 0126（10 μmol/L）for 1 h；except for control group ，other four groups were treated with 2 μmol/L Aβ42 for 24 h to replicate the Alzheimer ’s disease cell model ；except for control group and model group ，other three groups were added with 100 μmol/L sinapic acid respectively. After 24 hours of continuous culture ，survival rate of PC 12 cells was detected and the morphology of PC 12 cells was observed. The content of Aβ42，mRNA expression of cAMP response element binding protein （CREB），protein expression of cyclic adenosine monophosphate （cAMP），protein kinase A （PKA），CREB signaling pathway and phosphorylated CREB （p-CREB）were detected. RESULTS After treated with sinapic acid ，the survival rate of PC 12 cells，mRNA expression of CREB and protein expressions of cAMP ，PKA and p-CREB were increased significantly （P＜0.05），while the content of Aβ42 was decreased significantly （P＜0.05）；cell morphology was significantly improved and synapses increased. After intervened with PI 3K and ERK inhibitors ，the survival rate of PC 12 cells，above mRNA and protein expressions were reversed significantly （P＜0.05 or P＜0.01）；cell morphology was irregular ，the fragments increased ，and the synaptic connections decreased. CONCLUSIONS Sinapic acid can improve the survival rate of PC 12 cells injured by A β 42，improve cell （No.2021-KYYWF-0349） morphology and decrease the content of Aβ42，the mechanism of which may be associated with promoting the gene transcription of CREB ， and activating cAMP/PKA/CREB signaling pathway.

Effects of Sinapic Acid on Improving PC 12 Cell Damage Induced by Aβ1-42 and BDNF/TrkB/ERK Signaling Pathway / 中国药房

OBJECTIVE：To study the improvement effects of sinapic acid （SA）on PC 12 cell damage induced by Aβ1-42，and to investigate its effect on brain-derived neurotrophic factor （BDNF）/tyrosine kinase B （TrkB）/extracellular signal-regulated kinase （ERK）signaling pathway. METHODS ：PC12 cells were divided into blank group ，model group ，SA low-dose and high-dose groups（50，100 μmol/L）. Except for blank group ，cell damage was induced by Aβ1-42 in other groups ；24 h after modeling ， administration groups were added with the corresponding solution and cultured for 24 h. Morphological changes of cells in each group were observed. Cell survival rate ，mRNA expression and protein level of BDNF ，protein expression of TrkB ，ERK1/2 and phosphorylated ERK 1/2（p-ERK1/2）were detected. p-ERK/ERK ratio was calculated. RESULTS ：Compared with blank group ，the model group had shorter synapses ，looser intercellular junctions ，poor adhesion ，dim cytoplasm and more granules in cytoplasm. Cell survival rate and mRNA expression and protein level of BDNF ，the relative expression of TrkB and p-ERK 1/2 protein，p-ERK/ ERK ratio were significantly decreased （P＜0.05 or P＜0.01）. Compared with model group ，in SA high-dose group the pathological changes of the cells were significantly improved ，the survival rate of the cells ，the mRNA expression and protein level of BDNF，the relative expression of TrkB and p-ERK 1/2 protein， p-ERK/ERK ratio were significantly increased （P＜0.05 or P＜ 0.01）. CONCLUSIONS：SA can i mprove PC 12 cells damage induced by Aβ1-42，the mechanism of which may be associated with activating BDNF/TrkB/ERK signaling pathway. qq.com

Pharmacokinetics of Sinapic Acid from Stir-fried Raphani Semen in Rats and Its PK-PD Correlation Analysis / 中国实验方剂学杂志

Objective::To study the pharmacokinetics of sinapic acid from stir-fried Raphani Semen in normal rats and the correlation between pharmacokinetics-pharmacodynamics (PK-PD) in asthma rats. Method::Normal rats received 4.5, 9, 18 g·kg-1 of stir-fried Raphani Semen by oral administration, respectively. Blood was taken from ophthalmic venous plexus at different time points according to the experimental design, the plasma concentration of sinapic acid was analyzed by UHPLC-MS/MS, and data analysis was performed using DAS 3.2.8 software to obtain the pharmacokinetic parameters. Rat asthma model was established by intraperitoneal injection of ovalbumin with aluminum hydroxide, and treated with ethanol extract of stir-fried Raphani Semen (low and high doses of 4.5, 9 g·kg-1). After treatment for 3 weeks, taking blood at different time points, plasma and serum were separated. UHPLC-MS/MS was established for the determination of plasma concentration of sinapic acid, contents of interleukin-5 (IL-5), immunoglobuin E (IgE), tumor necrosis factor-α (TNF-α) in serum at different time points were detected by enzyme-linked immunosorbent assay (ELISA), DAS 3.2.8 software was used for PK-PD model fitting and data analysis. Result::After normal rats were administrated with low, medium and high doses of stir-fried Raphani Semen, the peak concentration (Cmax) of sinapic acid in plasma were (29.35±10.32), (62.70±27.47), (137.33±40.95) μg·L-1, its area under the curve (AUC0-t) were (92.83±27.16), (240.74±75.09), (633.95±195.88) μg·L-1·h, its peak time (Tmax) were (2.58±0.80), (3.00±0), (5.50±1.23) h, respectively. Compared with the low dose group, AUC0-t and mean retention time (MRT0-t) were all increased in the medium and high dose groups, showing statistical differences (P<0.05, P<0.01). The linear relationship of AUC0-t in sinapic acid was good within the dose range of 4.5-18 g·kg-1. After treating with ethanol extract of stir-fried Raphani Semen for 0.083, 0.167 h, compared with the model group of asthmatic rats, serum levels of IL-5, IgE, TNF-α of the medication groups were decreased to different degrees (P<0.05, P<0.01). Cmax of sinapic acid in the low and high dose groups were (58.43±29.94), (61.16±18.79) μg·L-1, its AUC0-t were (188.75±37.07), (247.90±36.89) μg·L-1·h, respectively. AUC0-t, apparent volume of distribution (Vz/F) and clearance rate (CLz/F) all increased significantly with the increase of dose. The best pharmacokinetic model of sinapic acid was fitted as a one-compartment model for extravascular administration, PK-PD model may be applicable to indirect connection model. Conclusion::The plasma concentration of sinapic acid is correlated with contents of IL-5, IgE and TNF-α, dosage and functional state (pathological or physiological state) can affect the pharmacokinetic behavior of sinapic acid from stir-fried Raphani Semen in rats, and it has a certain correlation with the anti-asthmatic effect.

Study on the Mechanism of Sinapic Acid against PC 12 Cell Injury Induced by Aβ1-42 Based on PI 3K/Akt/GSK3β Signaling Pathway / 中国药房

OBJECTIVE：To investigate the mechanism of sinapic acid （SA）against PC 12 cell injury induced by Amyloid β1-42 protein（Aβ1-42）based on PI 3K/Akt/GSK3β signaling pathway. METHODS：PC12 cells of rats were randomly divided into control group，Aβ group（Aβ1-42 2 μmol/L），Aβ+SA group（Aβ1-42 2 μmol/L+SA100 μmol/L），Aβ+SA+LY group [Aβ1-42 2 μmol/L+SA 100 μmol/L+LY294002（PI3K inhibitor ）10 μmol/L]，Aβ+LY group（Aβ1-42 2 μmol/L+LY294002 10 μmol/L）and LY group （LY294002 10 μmol/L）. Except for control group and LY group ，the cells of other groups were replicated the damage model with Aβ1-42. After 24 hours of culture ，the morphology of cells was obsened in each group with a microscope ，and MTT assay was adopted to determine the cell viability of PC 12 cells in each group. Western blotting assay was used to detect the expression of PI 3K，p-PI3K， Akt，p-Akt，GSK3β and p-GSK3β in cells of each group. RESULTS：Compared with control group ，the number of cells decreased and some synaptic breaks disappeared in Aβ group while cell viability，ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β in Aβ group were decreased significantly（P＜0.05 or P＜0.01）. Compared with Aβ group，the cells became round and synapses became more in Aβ+SA group while cell viability，the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β were increased significantly（P＜0.05）. Compared with Aβ+SA group，some synaptic breaks occurred in Aβ+SA+LY group while cell viability， the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK 3β/GSK3β were decreased significantly（P＜0.05）；Aβ+LY group had more cell debris，and t he cell viability was decreased ，but the difference was not significant ，and the ratio of p-PI 3K/PI3K，p-Akt/Akt and p-GSK3 β/GSK3 β had no significant change （P＞0.05）; LY294002 alone had no significant effect on morphology ，cellviability and the ratio of p-PI 3K/PI3K，p-Akt/Akt or p-GSK 3β/ GSK3 β （P＞0.05）. CONCLUSIONS ： SA may play aprotective role against PC 12 cell injury induced by A β 1-42 through activating PI 3K/Akt/GSK-3β.

Chemical constituents from rhizomes of Cimicifuga dahurica / 中草药

To isolate and identify the chemical constituents from the rhizome of Cimicifuga dahurica. Methods The isolation and purification of 60% EtOH extract of the rhizomes of C. dahurica were carried out through various modern chromatographic separation techniques: HP-20, silica gel, ODS, Sephadex LH-20 column and semi-preparative HPLC. And the structures of the compounds were identified based on spectroscopic data and physicochemical properties. Results Twenty compounds were isolated and identified as cimicifugaside F (1), (+) (2S,3R)-2-(4-hydroxy-3-methoxyphenyl)-3-[(β-D-glucopyranosyloxy) methyl]-7-methoxybenzofuran-5-propenoic acid (2), 5-hydroxy-2-methoxybenzoic acid (3), benzoic acid 4-O-β-D-glucoside (4), isoferulic acid (5), ferulic acid (6), trans-ferulic acid 4-O-β-D-allopyranoside (7), trans-ferulic acid 4-O-β-D-glucoside (8), (E)-sinapic acid 4-O-β-D-glucoside (9), 6,6’-di-O-sinapoylsurcose (10), piscidic acid (11), fukinolic acid (12), N-trans-feruloyltyramine 4-O-β-D-allopyranoside (13), N-trans-3’-methoxy-4’-feruloyltyramine-4-O-β-D-allopyranoside (14), N-trans-3’-methoxy-4’- feruloyltyramine-4-O-β-D-glucoside (15), grevilloside G (16), (-)-syringaresinol (17), (-)-syringaresinol 4,4’-di-O-β-D- allopyranoside (18), (+)-isolarisiresinol 3a-O-β-D-glucoside (19), (-)-5’-methoxyisolariciresinol 3a-O-β-D-glucoside (20). Conclusion Compound 1 was identified as a new lignan, and compounds 2-4, 8-10, 15-17 and 20 were isolated from Cimicifuga genus for the first time.

Effects of processing on pharmacokinetics of Descurainiae Semen's constituents in rats / 中国中药杂志

An UPLC-MS/MS method simultaneously determining contents of quercetin-3-O-β-D-glucose-7-O-β-D-gentiobioside and sinapic acid in rats' plasma was firstly established and applied to study the effects of processing on pharmacokinetics of Descurainiae Semen's active constituents. Complantatoside A as internal standard,methanol used for protein precipitation,the method was validated according to the instructions of CFDA. Rats' plasma was collected after being oral administrated equal dosage of 60% ethanal extract of raw or processed Descurainiae Semen at different point of time,then the concentrations were determined to calculate pharmacokinetic parameters using DAS 3. 2. 6. And the parameters were analyzed using SPSS 23. 0,meantime the concentration-time curve was drawn.The results showed that processing had no effects on the pharmacokinetics of QGG,but could improve the absorption of sinapic acid and slow down the excretion.

Determination of Contents of Five Components in Descurainiae Semen Before and After Being Processed by HPLC / 中国实验方剂学杂志

Objective:HPLC for the determination of five components in Descurainiae Semen was established to investigate the change rule of contents of five components in the herb before and after being processed. Method:The contents of quercetin-3-O-β-D-glucose-7-O-β-D-gentiobioside(QGG),sinapic acid,quercetin-3-O-β-D-glucopyranoside(QG),isorhamnetin-3-O-β-D-glucopyranoside(IG) and 1,2-di-O-sinapoyl-β-D-glucopyranose(SG) was determined simultaneously by HPLC,the change rule of contents of these components before and after processing and its reasons were analyzed.Waters Symmetry® C18 column(4.6 mm×250 mm,5 μm) was employed,and the mobile phase was acetonitrile(A)-1% acetic acid aqueous solution(B) for gradient elution(0-5 min,5%-10%A;5-15 min,10%-13%A;15-23 min,13%-20%A;23-43 min,20%-25%A;43-46 min,25%A;46-55 min,25%-40%A;55-60 min,40%A).The flow rate was 1 mL·min-1.The detection wavelength was set at 265 nm,the injection volume was 10 μL,and the column temperature was 30℃. Result:Contents of the above five components before processing were 0.114 3%,0.041 6%,0.036 2%,0.022 6% and 0.097 6%;after processing,the contents of these five components turn into 0.107 4%,0.011 3%,0.034 2%,0.021 9% and 0.058 9%;among them,the contents of these five components decreased by 6.04%,72.84%,5.52%,3.10% and 39.65%,respectively. Conclusion:The contents of these five components in Descurainiae Semen is reduced to varying degrees after processing.The contents of phenylpropanoids decrease significantly,while the contents of flavonoid glycosides do not change significantly.

Phenolic glycosides from root of Oplopanax elatus / 中草药

Objective To investigate the hydrophilic constituents from the anti-colorectal cancer extract of Oplopanax elatus. Methods The compounds were isolated and purified using macroporous resin, silica gel, ODS gel and pre-HPLC, and their chemical structures were identified by spectral data and physicochemical properties. The extracts and compounds from O. elatus were screened for anti-proliferation on HCT-116 and HT-29 cancer cell lines. Results Eleven phenolic compounds had been purified and identified from the n-butanol fraction including six phenylpropanoid glycosides: (E)-sinapic acid-4-O-β-D-glucopyranoside (1), 3- hydroxyphenethyl alcohol-4-O-β-D-glucopyranoside (2), 3-methoxycinnamyl alcohol-4-O-β-D-glucopyranoside (3), homovanillyl alcohol-4-O-β-D-glucopyranoside (4), dihydrosyringin (5), and syringin (6); And five lignan glycosides: 3,3'-dimethoxy-4,9,9'- trihydroxy-4',7-epoxy-5',8-lignan-4,9-bis-O-β-D-glucopyranoside (7), (+)-5,5'-dimethoxylariciresinol 4'-O-β-D-glucopyranoside (8), (+)-isolariciresinol-9'-O-β-D-glucopyranoside (9), (+)-isolariciresinol-4-O-β-D-glucopyranoside (10), and (+)-5,5'-dimethoxylariciresinol- 9'-O-β-D-glucopyranoside (11). All the phenolic glycosides showed no significant effects on the proliferation of HCT-116 and HT-29 cancer cell lines with IC50 > 100 μmol/L. Conclusion Compounds 4, 6, 9, and 11 are isolated and purified from this herb for the first time, while compounds 1, 2, and 10 are firstly obtained from the genus Oplopanax.

Effects of sinapic acid on proliferation and apoptosis of rat vascular smooth muscle cells induced by high glucose / 中国病理生理杂志

[ ABSTRACT] AIM:To investigate the effects of sinapic acid ( SA) on the proliferation and apoptosis of rat vas-cular smooth muscle cells (VSMCs) induced by high glucose (HG).METHODS:Cultured A7r5 cells were randomly di-vided and treated as indicated.The cell viability was determined by MTT assay.DNA synthesis was measured by BrdU as-say.Cell cycle progression and cell apoptotic rate were determined by flow cytometry analysis.The levels of reactive oxygen species (ROS) were detected by ELISA.The protein levels of cyclin D1, P21, P27, phosphorylated protein kinase C (p-PKC), p-P38 andβ-actin were evaluated by Western blot.RESULTS:Compared with control group, the viability of A7r5 cells was significantly enhanced, the DNA synthesis was increased, the cell cycle progression was promoted, the levels of ROS were elevated, the cell apoptotic rate was reduced, the protein expression of P21 and P27 was decreased, and the pro-tein levels of cyclin D1, p-PKC and p-P38 were increased in HG group (all P<0.05).These effects were reversed by SA (0.1, 1 and 10 μmol/L) treatment in a dose-dependent manner (all P<0.05).Both P38 inhibitor SB203580 and PKC inhibitor chelerythrine significantly inhibit HG-induced PKC/P38 activation and cell viability ( P <0.05).CONCLU-SION:SA inhibits HG-induced VSMCs proliferation and promotes cell apoptosis via reducing PKC/P38 activation.

Effects of Sinapic Acid of 4 Vessel Occlusion Model-Induced Ischemia and Cognitive Impairments in the Rat

OBJECTIVE: Sinapic acid (SA, Sinapine), small naturally occurring hydroxycinnamic acid, has a GABA(A) receptor agonistic property and free radical scavenging activity. We examined potential neuroprotective effects of sinapic acid (SA) using global cerebral ischemia animal model. METHODS: MTT assay was performed to determine cytotoxic effects of SA. To examine the neuroprotective effects of SA, SA was administrated for 14 d before 4-vessel occlusion. Also, to determine whether SA prevents cognitive impairment, Morris water maze was performed. RESULTS: In this study, the efficacy of SA for the prevention of neuronal damage and for the reduction of memory impairment was investigated. CONCLUSION: The results indicate that SA confers significant neuroprotection especially for ischemic hippocampal neurons.