Injury In PC12 Cells Research Articles

Alkaloids with Their Protective Effects Against Aβ25-35-Induced PC-12 Cell Injury from the Tubers of Pinellia pedatisecta Schott.

Seven new alkaloids [1, (±)-2, (±)-3, 4, and 5] and one new natural product (6), along with eight known analogues, were isolated from the tubers of Pinellia pedatisecta Schott. Their structures were determined by a comprehensive analysis of spectroscopic data, including HRESIMS, and electronic circular dichroism (ECD). In addition, the results of the bioactivity evaluation showed that compounds (±)-3, 6, and 9 exhibited significantly protective effects against Aβ25-35-induced PC-12 cell injury and ameliorated cell viabilities by decreasing the levels of the reactive oxidative species (ROS) and mitochondrial membrane potential (MMP).

Isoliquiritigenin alleviates cerebral ischemia-reperfusion injury by reducing oxidative stress and ameliorating mitochondrial dysfunction via activating the Nrf2 pathway

Cerebral ischemia-reperfusion injury (CIRI) refers to a secondary brain injury that occurs when blood supply is restored to ischemic brain tissue and is one of the leading causes of adult disability and mortality. Multiple pathological mechanisms are involved in the progression of CIRI, including neuronal oxidative stress and mitochondrial dysfunction. Isoliquiritigenin (ISL) has been preliminarily reported to have potential neuroprotective effects on rats subjected to cerebral ischemic insult. However, the protective mechanisms of ISL have not been elucidated. This study aims to further investigate the effects of ISL-mediated neuroprotection and elucidate the underlying molecular mechanism. The findings indicate that ISL treatment significantly alleviated middle cerebral artery occlusion (MCAO)-induced cerebral infarction, neurological deficits, histopathological damage, and neuronal apoptosis in mice. In vitro, ISL effectively mitigated the reduction of cell viability, Na+-K+-ATPase, and MnSOD activities, as well as the degree of DNA damage induced by oxygen-glucose deprivation (OGD) injury in PC12 cells. Mechanistic studies revealed that administration of ISL evidently improved redox homeostasis and restored mitochondrial function via inhibiting oxidative stress injury and ameliorating mitochondrial biogenesis, mitochondrial fusion-fission balance, and mitophagy. Moreover, ISL facilitated the dissociation of Keap1/Nrf2, enhanced the nuclear transfer of Nrf2, and promoted the binding activity of Nrf2 with ARE. Finally, ISL obviously inhibited neuronal apoptosis by activating the Nrf2 pathway and ameliorating mitochondrial dysfunction in mice. Nevertheless, Nrf2 inhibitor brusatol reversed the mitochondrial protective properties and anti-apoptotic effects of ISL both in vivo and in vitro. Overall, our findings revealed that ISL exhibited a profound neuroprotective effect on mice following CIRI insult by reducing oxidative stress and ameliorating mitochondrial dysfunction, which was closely related to the activation of the Nrf2 pathway.

Zhachong Shisanwei pill drug-containing serum protects H2O2-Induced PC12 cells injury by suppressing apoptosis, oxidative stress via regulating the MAPK signaling pathway.

Zhachong Shisanwei Pill (ZSP) is a classical Mongolian formula that combines 13 types of Chinese medicinal materials and has been used for treating ischemic stroke (IS) for centuries. However, the underlying molecular mechanisms have yet to be fully elucidated. The aim of this study is to explore potential mechanism of ZSP on nerve cells in cerebral ischemic injury. To simulate the pathological process of oxidative stress following IS, an injury model using PC12 cells was induced with hydrogen peroxide (H2O2). Afterward, PC12 cells were treated with ZSP medicated serum at low, medium, and high doses. Various assays were conducted to assess cell viability and oxidative stress indicators, including lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Cell apoptosis was evaluated through morphological assessment and flow cytometry. Additionally, the expression levels of apoptosis-related proteins (Bcl-2, Bax, Caspase-9, Caspase-3, PARP) and signaling pathway proteins (JNK, phosphorylated JNK, ERK, phosphorylated ERK, p38, and phosphorylated p38) were measured using automated Western blotting. Our findings indicate that ZSP medicated serum preconditioning improves the condition of PC12 cells injured by H2O2. Specifically, it increased cell survival rates and reduced LDH release. Additionally, ZSP treatment decreased ROS levels and MDA content, while enhancing the activity of SOD and CAT in the injured PC12 cells. ZSP also reversed the depolarization of mitochondrial membrane potential and protected cells from apoptosis by modulating the expression of apoptosis-related proteins, including Bcl-2, Bax, Caspase-9, Caspase-3, and PARP. Furthermore, the overactivation of the MAPK signaling pathway due to H2O2-induced injury was inhibited, as evidenced by the downregulation of phosphorylated JNK, ERK, and p38 levels. Mongolian medicine ZSP demonstrates protective effects against H2O2-induced oxidative stress and apoptosis in PC12 cells. The underlying mechanism may involve the inhibition of the MAPK signaling pathway, enhancement of antioxidant enzyme activity, reduction of intracellular peroxidation levels, and suppression of intrinsic apoptosis pathways.

Design, synthesis and neuroprotective activity of compound derived from Gastrodia elata Blume and borneol.

Traditional Chinese medicine Gastrodia elata Blume (GEB) possesses properties that soothe the liver and dispel wind. Its constituents exhibit numerous pharmacological properties, including neuroprotective effects, analgesic properties for headache relief, memory enhancement, and others. Borneol enhances drug absorption by traversing the blood-brain barrier, thereby improving its bioavailability and therapeutic efficacy. The research aimed to design innovative drug molecules and contribute to the beneficial exploration of compound Chinese medicine modernization. This study employed the strategy of "compound Chinese medicine molecular chemistry" to integrate and fuse the effective substances of compound Chinese medicines. An excitotoxic injury model was established by exposing PC12 cells to glutamate. Cell viability was quantitatively evaluated utilizing a colorimetric assay with the CCK-8 reagent kit. Genecards, Disgenet, and OMIM databases were used to identify potential disease-related targets. Molecular docking methods were performed to predict the binding interactions between compounds and core targets. We designed and synthesized compounds TB-1 to TB-16. Following the evaluation of their safety, TB-1, TB-2, TB-12, and TB-16 were selected for further investigation of their neuroprotective properties. The compound designed in this study exhibits a dose-dependent protective effect on glutamate-damaged PC12 cells. Further network pharmacology and molecular docking analyses indicate that TB-2 possesses a potential therapeutic effect against cerebral ischemia, and its possible targets were SRC, MAPK1 and KDR. The results indicated that TB-2 displayed a significant neuroprotective effect against Glu-induced injury in PC12 cells, suggesting potential therapeutic implications for cerebral ischemia.

NMC‐4 Ameliorates Depression‐Like Behavior and Neuroinflammation Caused by Chronic Unpredictable Mild Stress

ABSTRACTDepression is a prevalent mental disorder, but the side effects of antidepressants also make depressed patients resistant. Effective and safe antidepressants should be developed from traditional herbs, with the aim of reducing the side effects of antidepressants and improving the efficacy of drugs. In this study, the new macamide compound‐4 (NMC‐4) was synthesized for the first time, addressing the problem of difficult extraction, isolation, and low content of natural macamide. NMC‐4 was characterized using mass spectrometry, nuclear magnetic resonance, and infrared spectroscopy. The protective effect of NMC‐4 against cell injury was demonstrated to be stronger than that of natural macamide (N‐benzylhexadecanamide, XA) using a PC12 cell injury model. The study explored the effects of NMC‐4 on chronic unpredictable mild stress (CUMS)‐induced depressive symptoms. NMC‐4 significantly improved depressive‐like behaviors. NMC‐4 ameliorated CUMS‐induced depressive‐like behaviors by mitigating neuroinflammation and modulating the NF‐κB/Nrf2 and BDNF/PI3K/Akt pathways.

Network pharmacology screening, in vitro and in vivo evaluation of antianxiety and antidepressant drug-food analogue

BackgroundDepression and anxiety disorders are prevalent psychiatric conditions, and currently utilized chemical drugs typically come with significant adverse effects. China boasts a wealth of medicinal and food herbs known for their safe and effective properties. PurposeThis study aimed to develop novel formulations with improved antidepressant and anxiolytic effects derived from medicinal and food herbs. Study designScreening combinations with antidepressant and anxiolytic effects using techniques such as network pharmacology and validating their effects in vitro and in vivo experiments. MethodsUtilizing network pharmacology and molecular docking, we identified the top ten medicinal herbs with anxiolytic and antidepressant potential. Herbs with cytoprotective effects and non-toxic characteristics were further screened to formulate the herbal blends. Subsequently, we established a PC12 cell injury model and a chronic unpredictable mild stress (CUMS) model in mice to assess the effects of our formulations. ResultsTen medicinal herbs were initially screened, and six of them were deemed suitable for formulating the blend, namely Gancao, Dazao, Gouqizi, Sangye, Huangqi, and Jinyinhua (GDGSHJ). The GDGSHJ formulation reduced Lactate Dehydrogenase (LDH) leakage, decreased apoptosis, and demonstrated a favorable antidepressant and antianxiety effect in the CUMS mouse model. Besides, GDGSHJ led to the upregulation of serum 5-Hydroxytryptamine (5-HT) content and brain tissue 5-HT, Gamma-aminobutyric acid (GABA), and Dopamine (DA) levels. It also downregulated the expression of SLC6A4 and SLC6A3 genes in the mouse hippocampus while upregulating HTR1A, DRD1, DRD2, and GABRA1 genes. ConclusionOur formulation exhibited robust antidepressant and antianxiety effects without inducing substantial toxicity. This efficacy appears to be mediated by the expression of relevant genes within the hippocampus of mice. The formulation achieved this effect by balancing 5-HT levels in the serum and DA, GABA, and 5-HT levels within brain tissue.

RNA-seq revealed the protective effect of Huangqi Guizhi Wuwu Decoction against cisplatin induced PC12 cell injury

Background Chemotherapy-induced peripheral neuropathy (CIPN) not only affects the tolerability of chemotherapy, but also causes intolerable and prolonged neuropathic pain in cancer patients. Currently, duloxetine is the only drug used to treat CIPN. However, the clinical use of this drug still faces several challenges. Therefore, we focused on traditional Chinese medicine (TCM) to find an effective and safe alternative medicine. Huangqi Guizhi Wuwu Decoction (HGWD) is a traditional Chinese medicine that has been clinically used for treating nerve pain for thousands of years. This study aimed to investigate the neuroprotective effect of HGWD on cisplatin-induced nerve injury in PC12 cells and to elucidate its potential mechanism of action. Methods HGWD-containing serum and blank serum were prepared from a rat model. The protective effects of HGWD on cisplatin (10 µmol/L)-induced PC12 cell injury were assessed by a Cell Counting Kit-8 (CCK-8) assay. RNA expression in HGWD-protected PC12 cells was analyzed using RNA-seq, and subsequently, differentially expressed genes (DEGs) were further analyzed using Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA). Results The CCK-8 results showed that pretreatment of PC12 cells with HGWD-containing serum (5%, 10%, 15%) significantly increased cells' viability to 10 µmol/L cisplatin-induced cell death. RNA-seq analysis revealed 843 DEGs in the CIPN group and 249 in the HGWD group. The GSEA results in this study suggest that HGWD may treat CIPN by enhancing axon guidance. Conclusions This study provides valuable evidence for using HGWD in treating CIPN, partially achieved by improving axon guidance pathways.

Hypomethylated leptin receptor reduces cerebral ischaemia-reperfusion injury by activating the JAK2/STAT3 signalling pathway.

To investigate the cerebroprotective effects of leptin in vitro and in vivo via the Janus kinase-2 (JAK2)/transcription factor signal transducer and activators of transcription-3 (STAT3) pathway and leptin receptors (LEPR). The study used the cellular oxygen-glucose deprivation (OGD) model in PC12 cells and the middle cerebral artery occlusion (MCAO) rat model of cerebral ischaemia-reperfusion injury (CIRI) to assess changes in gene expression and protein levels following leptin pretreatment. The methylated DNA immunoprecipitation (MeDIP) assay measured DNA methylation levels. The optimal leptin concentration for exerting neuroprotective effects against ischaemia-reperfusion injury in PC12 cells was 200 ng/ml in vitro, but excessive leptin diminished this effect. Leptin pretreatment in the MCAO rat model demonstrated a similar effect to previously reported leptin administration post-CIRI. In addition to regulating the expression of inflammation-related cytokines, Western blot analysis showed that leptin pretreatment upregulated BCL-2 and downregulated caspase 3 levels. The MeDIP analysis demonstrated that DNA methylation regulated LEPR gene expression in the MCAO rat model when leptin pretreatment was used. Exogenous leptin might bind to extra-activated LEPR by reducing the methylation level of the LEPR gene promoter region, which leads to an increase in phosphorylated JAK2/STAT3 and apoptotic signalling pathways.

Icariin Ameliorates D-galactose-induced Cell Injury in Neuron-like PC12 Cells by Inhibiting MPTP Opening.

Icariin (ICA) has a good neuroprotective effect and can upregulate neuronal basal autophagy in naturally aging rats. Mitochondrial dysfunction is associated with brain aging-related neurodegenerative diseases. Abnormal opening of the mitochondrial permeability transition pore (mPTP) is a crucial factor in mitochondrial dysfunction and is associated with excessive autophagy. This study aimed to explore that ICA protects against neuronal injury by blocking the mPTP opening and down-regulating autophagy levels in a D-galactose (D-gal)-induced cell injury model. A cell model of neuronal injury was established in rat pheochromocytoma cells (PC12 cells) treated with 200 mmol/L D-gal for 48 h. In this cell model, PC12 cells were pre-treated with different concentrations of ICA for 24 h. MTT was used to detect cell viability. Senescence associated β-galactosidase (SA-β-Gal) staining was used to observe cell senescence. Western blot analysis was performed to detect the expression levels of a senescence-related protein (p21), autophagy markers (LC3B, p62, Atg7, Atg5 and Beclin 1), mitochondrial fission and fusion-related proteins (Drp1, Mfn2 and Opa1), and mitophagy markers (Pink1 and Parkin). The changes of autophagic flow were detected by using mRFP-GFP-LC3 adenovirus. The intracellular ultrastructure was observed by transmission electron microscopy. Immunofluorescence was used to detect mPTP, mitochondrial membrane potential (MMP), mitochondrial reactive oxygen species (mtROS) and ROS levels. ROS and apoptosis levels were detected by flow cytometry. D-gal treatment significantly decreased the viability of PC12 cells, and markedly increased the SA-β-Gal positive cells as compared to the control group. With the D-gal stimulation, the expression of p21 was significantly up-regulated. Furthermore, D-gal stimulation resulted in an elevated LC3B II/I ratio and decreased p62 expression. Meanwhile, autophagosomes and autolysosomes were significantly increased, indicating abnormal activation of autophagy levels. In addition, in this D-gal-induced model of cell injury, the mPTP was abnormally open, the ROS generation was continuously increased, the MMP was gradually decreased, and the apoptosis was increased. ICA effectively improved mitochondrial dysfunction to protect against D-gal-induced cell injury and apoptosis. It strongly inhibited excessive autophagy by blocking the opening of the mPTP. Cotreatment with ICA and an mPTP inhibitor (cyclosporin A) did not ameliorate mitochondrial dysfunction. However, the protective effects were attenuated by cotreatment with ICA and an mPTP activator (lonidamine). ICA inhibits the activation of excessive autophagy and thus improves mitochondrial dysfunction by blocking the mPTP opening.

Investigation into Antioxidant Mechanism of Lycium barbarum Extract in Carbendazim-Induced PC12 Cell Injury Model through Transcriptomics and Metabolomics Analyses.

Lycium barbarum L., an important functional food in China, has antioxidant and antiaging activity. However, the exact antioxidant activity mechanism of Lycium barbarum extracts (LBE) is not well understood. Therefore, a carbendazim (CBZ)-induced PC12 cell injury model was constructed and vitrificated to study the antioxidant activity of fresh LBE on the basis of extraction parameter optimization via the full factorial design of experiments (DOE) method. The results showed that the pretreatment of PC12 cells with LBE could reduce the reactive oxygen species (ROS) level by 14.6% and inhibited the mitochondrial membrane potential (MMP) decline by 12.0%. Furthermore, the integrated analysis revealed that LBE played an antioxidant role by activating oxidative phosphorylation (OXPHOS) and restoring MMP, maintaining the tricarboxylic acid (TCA) cycle stability, and regulating the GSH metabolic pathway. The results of the present study provide new ideas for the understanding of the antioxidant function of LBE from a global perspective.

Ginsenoside Rb1 reduced ischemic stroke-induced apoptosis through endoplasmic reticulum stress-associated IRE1/TRAF2/JNK pathway.

The neuroprotective function of ginsenoside Rb1 (GRb1) in cerebral ischemia-reperfusion (I/R) was lately emphasized. However, whether GRb1 plays a regulatory role on endoplasmic reticulum (ER) stress-associated pathway in cerebral I/R damage is still unclear. The aim of this study is to explore the function of GRb1 in cerebral ischemia-induced ER stress and the underlying mechanism related to IRE1/TRAF2/JNK pathway. Longa method, cerebral infarct volume, and HE staining were used to evaluate the efficacy of GRb1 in mice with a mouse model of middle cerebral artery occlusion reperfusion (MCAO/R). We also investigated the effect and mechanism of GRb1 against ischemic stroke using in vitro oxygen-glucose deprivation reperfusion (OGD/R) model. We found that GRb1 could improve neurological scores, infarct volume, and histological injury in ischemic mice. Ischemic attack also activated neuronal apoptosis and ER stress, and this effect was attenuated by GRb1. In addition, GRb1 significantly reduced I/R-induced IRE1-TRAF2 interaction, IRE1, and JNK phosphorylation. The present study also confirmed that GRb1 significantly improved OGD/R-induced PC12 cells injury. GRb1 could decrease ER stress in OGD/R-injured PC12 cells, which was reflected by the decreased expression of GRP78 and CHOP. The ER stress inducer tunicamycin partially prevented the effects of GRb1 on cell viability, ER stress, and apoptosis after OGD/R, whereas the ER stress inhibitor 4-PBA exerted the opposite effect. Moreover, GRb1 markedly decreased IRE1-TRAF2 interaction, IRE1, and JNK phosphorylation in the presence of OGD/R insult. Furthermore, JNK inhibitor SP600125 and IRE1 inhibitor DBSA pretreatment further promoted the inhibition of GRb1 on ER stress induction and cell damage induced by OGD/R. Molecular docking further elucidated that the mechanism by which GRb1 improves cerebral ischemia maybe related to its direct binding to the kinase domain of IRE1, which in turn inhibited the phosphorylation of IRE1. Collectively, these results demonstrated that GRb1 reduced ischemic stroke-induced apoptosis through the ER stress-associated IRE1/TRAF2/JNK pathway and GRb1 has the potential as a protective drug for the treatment of cerebral ischemia.

Eight new dammarane-type triterpenoid saponins from Gynostemma pentaphyllum

Phytochemical investigation of Gynostemma pentaphyllum led to the purification of five novel dammarane-type triterpene isolates, gypenosides B1 − B5 (1–5). Their structures were determined through comprehensive 1D and 2D NMR spectroscopic analyses and HRESIMS data. Of note, 1–3 are inseparable mixtures of epimers due to their unstable nature, and a total of eight dammarane-type triterpene saponins were identified. Additionally, the protective activities of these new compounds against PC12 cell injury induced by hypoxia were evaluated.

USP7 alleviates neuronal inflammation and apoptosis in spinal cord injury via deubiquitinating NRF1/KLF7 axis

ABSTRACT Background Ubiquitin-specific protease 7 (USP7) has been found to be associated with motor function recovery after spinal cord injury (SCI). Therefore, its role and mechanism in SCI process need further exploration. Methods SCI rat models were established via performing laminectomy at the T9-T11 spinal vertebrae and cutting spinal cord tissues. SCI cell models were constructed by inducing PC12 cells with lipopolysaccharide (LPS). The protein levels of USP7, nuclear respiratory factor 1 (NRF1), Krüppel-like factor 7 (KLF7) and apoptosis-related markers were detected by western blot. Cell viability and apoptosis were tested by cell counting kit-8 assay and flow cytometry. The contents of inflammatory factors were examined using ELISA. The interaction between NRF1 and USP7 or KLF7 was analyzed by co-immunoprecipitation assay, chromatin immunoprecipitation assay and dual-luciferase reporter assay, respectively. Results USP7 was downregulated in SCI rat models and LPS-induced PC12 cells. Overexpressed USP7 promoted viability, while repressed apoptosis and inflammation in LPS-induced PC12 cells. USP7 could stabilize NRF1 protein expression via deubiquitination, and NRF1 knockdown reversed the protective effect of USP7 against LPS-induced PC12 cell injury. NRF1 is bound to KLF7 promoter to enhance its transcription. NRF1 overexpression inhibited LPS-induced PC12 cell inflammation and apoptosis via increasing KLF7 expression. Conclusion USP7 alleviated inflammation and apoptosis in LPS-induced PC12 cells via NRF1/KLF7 axis, indicating that targeting of USP7/NRF1/KLF7 axis might be a promising treatment strategy for SCI.

Brozopine ameliorates cognitive impairment via upregulating Nrf2, antioxidation and anti-inflammation activities.

Oxidative stress and inflammation are crucial factors contributing to the occurrence and development of vascular dementia (VD). In a previous study, we demonstrated that brozopine (BZP) is an anti-ischemic drug. In this study, a model of VD in rats with modified permanent bilateral common carotid artery occlusion (2-VO) was established in vivo, a model of cellular excitotoxicity/oxidative stress was established via L-glutamate-induced PC12 cell injury, a model of neuroinflammation was established in LPS-induced BV2 cells in vitro, and the ameliorative effect of BZP on cognitive impairment was assessed. BZP treatment improved memory deficit in VD rats through inhibiting Ca2+overload and the levels of oxidative stress, ferroptosis, and inflammatory markers (IL-1β, IL-6, and COX-2) in different brain regions. Additionally, we found that the levels of inflammatory markers in the plasma were also reduced in the VD rats. BZP was further found to have antioxidative stress, antiferroptosis (ferroptosis markers: GPX4, P53, and ACSL4), and antineuroinflammatory effects in PC12 and BV2 cells. Its mechanisms of action were found to be related to the activation of the Nrf2/TLR4/NF-κB pathway; the protective effect of BZP was partially inhibited after using Nrf2-specific inhibitors. Thus, BZP has therapeutic properties for the potential mitigation of cognitive impairment.

Chemical Constituents of the Fruits of Cornus Officinalis and Evaluation of their Neuroprotective Activity.

The phytochemical investigation of the fruits of Cornus officinalis yielded a new phenolic acid derivative, neophenolic acid A (1), and a novel flavonoid glycoside, (2R)-naringenin-7-O-β-(6''-galloyl-glucopyranoside) (2 a), along with six known flavonoid glycosides (2 b-7). Their structures were determined by 1D, 2D NMR and HRESIMS data. The absolute configuration of 1 was established by ECD analysis. Compounds 1- 7 were evaluated for their neuroprotective activities against corticosterone (CORT)-induced injury in PC-12 cells. Compounds 1, 2 a, 2 b, 5, and 6 exhibited neuroprotective activities against CORT-induced neurotoxicity in PC-12 cells. The underlying mechanism study suggested that compounds 1, 2 a, 2 b, 5, and 6 were able to attenuate CORT-induced apoptosis and damage, increase the levels of MMP and decrease Ca2+ inward flow in PC-12 cells.

Identification of antidepressant constituents from Xiangfu-chuanxiong herbal medicine pair via spectrum-effect relationship analyses, molecular docking and corticosterone-induced PC12 cells

Herbal medicine pair, composed of two single herbs, is a relatively fixed minimum prescription unit in the traditional Chinese medicine's formula and has special significance in clinic. The combination of Xiangfu (the rhizoma of Cyperus rotundus L, XF) and Chuanxiong (the rhizoma of Ligusticum chuanxiong Hort, CX) has been recoded as an herbal medicine pair XF-CX in the Yuan Dynasty (1347 CE) of China and widely used in traditional Chinese medicine formula, including Chaihu Shugan San, which has been clinically used for treatment of depression. However, the optimal ratio of the XF-CX herbal medicine pair and its antidepressant constituents are still unclear. Herein, the antidepressive-like effects of XF-CX herbal medicine pairs with different ratios of XF and CX (2:1, 1:1, 1:2) were evaluated using behavioral despair animal models in mice, and then its potential antidepressant constituents were recognized by spectrum-effect relationship analyses. Finally, the potential antidepressant constituents of the XF-CX herbal medicine pair were validated by molecular docking with glucocorticoid receptor and corticosterone (CORT)-induced PC12 cell injury model. The results indicated that different ratios of XF-CX pairs had antidepressive-like effects, and the XF-CX (2:1) exhibited a more significant effect. Thirty-two potential antidepressant constituents in the XF-CX herbal medicine pair were screened out from the spectrum-effect relationship combined molecular docking analyses. Among them, senkyunolide A, cyperotundone, Z-ligustilide, and levistilide A were validated to have protective effects against CORT-induced injury in PC12 cells. Our findings not only obtained the optimal ratio of XF-CX in the herbal medicine pair for the treatment of depression but also its potential antidepressant constituents, which will benefit in elucidating the mechanism of action and promoting the application of the herbal medicine pair in the clinic.

Ginsenoside Rg_1 ameliorates OGD/R-induced PC12 cell injury by inhibiting autography via IRE1-JNK-CHOP pathway

This study investigated the protective effect of ginsenoside Rg_1(GRg_1) on oxygen and glucose deprivation/reoxygenation(OGD/R)-injured rat adrenal pheochromocytoma(PC12) cells and whether the underlying mechanism was related to the regulation of inositol-requiring enzyme 1(IRE1)-c-Jun N-terminal kinase(JNK)-C/EBP homologous protein(CHOP) signaling pathway. An OGD/R model was established in PC12 cells, and PC12 cells were randomly classified into control, model, OGD/R+GRg_1(0.1, 1, 10 μmol·L~(-1)), OGD/R+GRg_1+rapamycin(autophagy agonist), OGD/R+GRg_1+3-methyladenine(3-MA,autophagy inhibitor), OGD/R+GRg_1+tunicamycin(endoplasmic reticulum stress agonist), OGD/R+GRg_1+4-phenylbutyric acid(4-PBA, endoplasmic reticulum stress inhibitor), and OGD/R+GRg_1+3,5-dibromosalicylaldehyde(DBSA, IRE1 inhibitor) groups. Except the control group, the other groups were subjected to OGD/R treatment, i.e., oxygen and glucose deprivation for 6 h followed by reoxygenation for 6 h. Cell viability was detected by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide(MTT) assay. Apoptosis was detected by Hoechst 33342 staining, and the fluorescence intensity of autophagosomes by the monodansylcadaverine(MDC) assay. Western blot was employed to determine the expression of autophagy-related proteins(Beclin1, LC3-Ⅱ, and p62) and the pathway-related proteins [IRE1, p-IRE1, JNK, p-JNK, glucose-regulated protein 78(GRP78), and CHOP]. The results showed that GRg_1 dose-dependently increased the viability of PC12 cells and down-regulated the expression of Beclin1, LC3-Ⅱ, p-IRE1, p-JNK, GRP78, and CHOP, compared with the model group. Furthermore, GRg_1 decreased the apoptosis rate and MDC fluorescence intensity and up-regulated the expression of p62 protein. Compared with the OGD/R+GRg_1(10 μmol·L~(-1)) group, OGD/R+GRg_1+rapamycin and OGD/R+GRg_1+tunicamycin groups showed increased apoptosis rate and MDC fluorescence intensity, up-regulated protein levels of Beclin1, LC3-Ⅱ, p-IRE1, p-JNK, GRP78, and CHOP, decreased relative cell survival rate, and down-regulated protein level of p62. The 3-MA, 4-PBA, and DBSA groups exerted the opposite effects. Taken together, GRg_1 may ameliorate OGD/R-induced PC12 cell injury by inhibiting autophagy via the IRE1-JNK-CHOP pathway.

Dammarane-type triterpenoids from Gynostemma longipes and their protective activities on hypoxia-induced injury in PC12 cells

Sixteen new dammarane-type triterpenoid saponins (1–16) featuring diverse structural variations in the side chain at C-17, along with twenty-one known analogues (17–37), have been isolated from the rhizomes of Gynostemma longipes C. Y. Wu, a plant renowned for its medicinal and edible properties. The structural elucidation of these compounds was accomplished through comprehensive analyses of 1D and 2D NMR and HRMS spectroscopic data, supplemented by comparison with previously reported data. Subsequent assays on the isolates for their protective effects against hypoxia-induced damage in pheochromocytoma cells (PC12 cells) revealed that nine saponins exhibited significant anti-hypoxic activities. Further investigation into the anti-hypoxia mechanisms of the representative saponins demonstrated that compounds 22 and 36 markedly reduced the levels of hypoxia-induced apoptosis. Additionally, these compounds were found to decrease the release of lactate dehydrogenase (LDH) and malondialdehyde (MDA), while increasing the activity of superoxide dismutase (SOD), thereby indicating that the saponins could mitigate hypoxia-induced injuries by ameliorating apoptosis and oxidative stress. These findings offer substantial evidence for the future utilization and development of G. longipes, identifying dammarane-type triterpenoid saponins as its active anti-hypoxic constituents.

LncRNA NEAT1 promotes MPP+ induced injury of PC12 cells and accelerates the progression of Parkinson's disease in mice through FUS mediated inhibition of PI3K/AKT/mTOR signalling pathway

Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is involved in the progression of Parkinson's disease (PD), but the specific regulatory role needs further exploration. This study showed that the expression of NEAT1 was upregulated in the cerebrospinal fluid (CSF) and peripheral blood of patients with different stages of PD. 1-Methyl-4-phenylpyridine (MPP)-treated PC 12 cells were transfected with si-NEAT1, and MPP treatment promoted cell apoptosis, oxidative stress and inflammatory factor secretion. Si-NEAT1 reversed the effects of MPP. NEAT1 silencing eliminated the effect of MPP on the protein expression levels of LC3-II and p62/SQSTM1. By using an online bioinformatics database, Fused in Sarcoma (FUS) was confirmed to be an RNA binding protein of NEAT1, and it was highly expressed in the CSF and peripheral blood of patients with PD. Si-FUS was transfected into MPP-treated PC 12 cells to detect cell apoptosis, oxidative stress, inflammatory factor secretion and autophagy, and the results were the same as those of transfection of si-NEAT1. Furthermore, MPP treatment reduced the phosphorylation levels of PI3K, Akt and mTOR, whereas si-FUS reversed the effects of MPP. In vivo, compared with the model group, the PD mice showed reduced NEAT1 and FUS expression levels and activated PI3K pathway after being injected with si-NEAT1. The brain tissue of NEAT1-silenced PD mice had decreased inflammatory infiltration and apoptosis and increased neurological scores. In conclusion, NEAT1 is involved in PD progression through FUS-mediated inhibition of the PI3K/AKT/mTOR signalling pathway.

Study on the Neuroprotective Effects of Eight Iridoid Components Using Cell Metabolomics.

Iridoid components have been reported to have significant neuroprotective effects. However, it is not yet clear whether the efficacy and mechanisms of iridoid components with similar structures are also similar. This study aimed to compare the neuroprotective effects and mechanisms of eight iridoid components (catalpol (CAT), genipin (GE), geniposide (GEN), geniposidic acid (GPA), aucubin (AU), ajugol (AJU), rehmannioside C (RC), and rehmannioside D (RD)) based on corticosterone (CORT)-induced injury in PC12 cells. PC12 cells were randomly divided into a normal control group (NC), model group (M), positive drug group (FLX), and eight iridoid administration groups. Firstly, PC12 cells were induced with CORT to simulate neuronal injury. Then, the MTT method and flow cytometry were applied to evaluate the protective effects of eight iridoid components on PC12 cell damage. Thirdly, a cell metabolomics study based on ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was performed to explore changes in relevant biomarkers and metabolic pathways following the intervention of administration. The MTT assay and flow cytometry analysis showed that the eight iridoid components can improve cell viability, inhibit cell apoptosis, reduce intracellular ROS levels, and elevate MMP levels. In the PCA score plots, the sample points of the treatment groups showed a trend towards approaching the NC group. Among them, AU, AJU, and RC had a weaker effect. There were 38 metabolites (19 metabolites each in positive and negative ion modes, respectively) identified as potential biomarkers during the experiment, among which 23 metabolites were common biomarkers of the eight iridoid groups. Pathway enrichment analysis revealed that the eight iridoid components regulated the metabolism mainly in relation to D-glutamine and D-glutamate metabolism, arginine biosynthesis, the TCA cycle, purine metabolism, and glutathione metabolism. In conclusion, the eight iridoid components could reverse an imbalanced metabolic state by regulating amino acid neurotransmitters, interfering with amino acid metabolism and energy metabolism, and harmonizing the level of oxidized substances to exhibit neuroprotective effects.