Viability Of PC12 Cells Research Articles

Senkyunolide A attenuates cerebral ischemia-reperfusion injury by inhibiting NLRP3-mediated ferroptosis in PC12 cells.

Cerebral ischemia-reperfusion (I/R) is a serious complication in patients with ischemic stroke. Senkyunolide A (SenA) can alleviate neuronal cell damage induced by cerebral I/R; however, the exact action mechanism remains unclear. An in vitro cellular injury model was established by inducing PC-12 cells with OGD/R. The viability of SenA-treated PC-12 cells with or without OGD/R induction was detected with CCK-8 assay while the cell apoptosis was detected using TUNEL. The secretion of inflammatory cytokines, the activity of ROS, mitochondrial membrane potential and mtROS level were measured with ELISA, ROS assay kits, JC-1 staining and MitoSOX Red assay, respectively. The level of Fe2+ was detected with Fe2+ assay kits and lipid peroxidation was detected with TBARS assay. The expressions of lipid peroxides were measured using corresponding assay kits. Western blot was used to measure the expressions of NLRP3, apoptosis-, and ferroptosis-related proteins. The transfection efficiency of OV-NLRP3 was also detected using Western blot. The present study showed that SenA could attenuate viability damage, inflammatory response, oxidative stress, apoptosis and ferroptosis in OGD/R-induced PC-12 cells and it was identified that the cytoprotective effects of SenA on PC-12 cells stimulated by OGD/R may be associated with the inhibition of NLPR3. Collectively, SenA protects neuronal cells against cerebral I/R injury through the inhibition of NLRP3-mediated ferroptosis.

FRESH extrusion 3D printing of type-1 collagen hydrogels photocrosslinked using ruthenium.

The extrusion bioprinting of collagen material has many applications relevant to tissue engineering and regenerative medicine. Freeform Reversible Embedding of Suspended Hydrogels (FRESH) technology is capable of 3D printing collagen material with the specifications and details needed for precise tissue guidance, a crucial requirement for effective tissue repair. While FRESH has shown repeated success and reliability for extrusion printing, the mechanical properties of completed collagen prints can be improved further by post-print crosslinking methodologies. Photoinitiator-based crosslinking methods are simple and have proven effective in strengthening protein-based materials. The ruthenium and sodium persulfate photoinitiator system (Ru(bpy)3/SPS) has been suggested as an effective crosslinking method for collagen materials. Herein, we describe the procedure our group has developed to combine extrusion-based 3D printing of type-1 collagen using FRESH technology with Ru(bpy)3/SPS photoinitiated crosslinking methods to improve the strength and stability of 3D printed collagen structures. Mechanical testing and cell biocompatibility assessments were performed to investigate the impact of Ru(bpy)3/SPS photoinitiated crosslinking and highlight the potential limitations of this method. These results demonstrate a significant improvement in the compressive strength of type-1 collagen samples as the Ru(bpy)3/SPS concentration increases. Additionally, type-1 collagen samples crosslinked with up to 1/10 mM Ru(bpy)3/SPS support PC12 cell viability over a period of 7 days. The primary limitations that were observed and described in detail in this protocol are: the FRESH slurry preparation, printing environment, extrusion printer hardware, and quality of the ruthenium reagent.

S32, a Novel 3-Acetylaminocoumarin Compound, Exerts Neuroprotective Effects through the Inhibition of Neuroinflammation and Oxidative Stress In Vitro and In Vivo.

Neuroinflammation and oxidative stress are key factors leading to neuronal injury. In this study, we investigated the role of S32, a novel 3-acetylaminocoumarin compound, in ameliorating neuronal injury induced by neuroinflammation and oxidative stress in vitro and in vivo. First, we found that S32 reduced the expression levels of p-P65 and p-P38, inhibited the nuclear translocation of P65, and lowered the levels of pro-inflammatory factors in LPS-induced BV2 cells, which indicated that S32 had an antineuroinflammatory effect. Second, BV2 cell culture medium was used as the conditioned medium to establish a model of oxidative damage in PC12 cells. It was found that S32 reduced the level of ROS and increased mitochondrial membrane potential of PC12 cells, which indicated that S32 can protect PC12 cells against conditioned medium-induced injury. Next, we found that S32 inhibited the decrease of cell viability of PC12 cells caused by H2O2, inhibited nuclear damage, decreased the level of ROS, increased MMP, activated the AKT and ERK pathways, increased Bcl-2 levels, and decreased Bax and Cleaved-Caspase3 expression levels, indicating that S32 ameliorated the damaging effects of H2O2-induced PC12 cells. Finally, we found that S32 exerted the antineuroinflammatory and apoptosis-inhibiting effects in LPS-induced mice. In conclusion, this study first demonstrated that S32, a novel 3-acetylaminocoumarin compound, can reduce neuroinflammation and neuroinflammation-induced neuronal injury, exerting an indirect protective effect on neurons, and also exert a direct protective effect on neurons by reducing oxidative stress.

Gradient galectin-1 coating technology: bionic multichannel nerve guidance conduits promote neural cell migration

Engineered nerve guidance conduits have been widely used to repair peripheral nerve injuries. Galectin-1 is an important biological cue that promotes axon regeneration and Schwann cell migration. In this study, a series of polycaprolactone-based nerve guidance conduits were prepared. First, we determined the concentration of galectin-1 (a member of the galactose lectin family) via the proliferation and morphology of Schwann cells and the viability, morphology, and axon length of PC12 cells. On this basis, nanofiber yarns coated with a uniform or unidirectionally linear gradient coating layer of galectin-1 were prepared by electrospinning to investigate the viability and migration of Schwann cells and neural stem cells on the surfaces. The unidirectional linear gradient coating with increasing galectin-1 content was found to promote the migration of both Schwann cells and neural stem cells. To construct nerve guidance conduits with encapsulated nanofiber yarns, we fabricated nerve guidance conduit walls composed of conjugately electrospun nanofiber yarns and random polycaprolactone nanofibers as the inner and outer layers. With a biocompatible light-absorbing dye, the nanofibers can be sealed via light welding to obtain a hollow polycaprolactone conduit. Finally, we prepared nerve guidance conduits containing nanofiber yarns coated with graded galectin-1 as well as hyaluronic acid methacryloyl hydrogel in the lumen. We found that the topology (nanofiber yarns and hyaluronic acid methacryloyl) and biological cues (gradient galectin-1 coating) synergistically accelerated the migration of Schwann cells and neural stem cells along multiple channels of nerve guidance conduits.

Influence of enzymatic modification on the structure, antioxidant activity, and prebiotic activity of ginseng neutral polysaccharide

The abundant ginseng neutral polysaccharide (GPN) has been neglected due to its lower activity compared to acidic polysaccharide in ginseng. Herein, the composite enzymes were used to modify the GPN and obtained the enzymatic-degradation-GPN (EGPN). The structural changes were further characterized by GPC, FT-IR, Congo red, XRD, zeta potential, TG, cryo-SEM and AFM. The antioxidant activity of GPNs in vitro was investigated by in vitro chemical experiments and oxidative stress-related indicators on PC12 cells damaged by Aβ25–35, and EGPN showed favorable antioxidant activity. In addition, EGPN metabolized by intestinal microbiota also significantly increased the viability of injured PC12 cells. Furthermore, in vitro fermentation model was used to investigate the differences of physicochemical properties of GPNs and their regulatory effects on the microbiota. EGPN enhanced the diversity of the microbiota and increased the concentration of short-chain fatty acids (SCFAs). Importantly, EGPN demonstrated a significant reduction in the presence of detrimental bacteria such as Enterococcus and Allobaculum, while simultaneously promoting the growth of beneficial microorganisms including Lactobacillus, Prevotella, and Ruminococcu. This study highlights the potential use of EGPN prepared by composite enzymatic degradation in antioxidant, neuroprotection and restoration of intestinal homeostasis.

Poliumoside inhibits apoptosis, oxidative stress and neuro-inflammation to prevent intracerebroventricular Streptozotocin-induced cognitive dysfunction in Sprague-Dawley Rats: in in-vivo, in-vitro and in-silico study.

Alzheimer's disease (AD) is a severe neurological illness causes cognitive decline and mortality if not treated early. However, the current therapeutic modalities are inefficient to manage the cognitive dysfunction of AD. Therefore, in the present manuscript, we have enumerated the pharmacological benefit of Poliumoside in the Streptozotocin-induced cognitive dysfunction in Sprague-Dawley (SD) rats. Initially, the cognitive dysfunction in rats was induced by the intracerebroventricular administration of Streptozotocin, then rats received PMD (5 mg and 10 mg/kg body weight) was given. Various behavioural analysis, such as Morris water maze (MWM), and object recognition tests (ORT), and locomotor analysis was conducted in PMD treated group. Various biochemical analysis was conducted to analyze the effect of PMD on hippocampus oxidative-nitrosative stress and pro-inflammatory cytokines. MTT assay and annexin V/PI staining was performed to analyse the effect of PMD on the cell viability and neuronal toxicity of PC12 cells, respectively. Molecular docking analysis was also conducted with crystal structure of human AChE. PMD treatment improved cognitive capacity in rats in MWM and ORT. Compared to STZ rats, PMD-treated rats had significantly higher locomotor activity and lower AChE activity. PMD also restores dopamine, 5-HT, and NE levels and reduces metabolic their deactivation as evidenced by increased levels of DOPAC, HVA, 5-HIAA. Nitrite, MDA, SOD, CAT, and GSH levels were restored near normal in PMD-treated rats, reducing hippocampus oxidative-nitrosative stress. Pro-inflammatory cytokines were similarly lowered in PMD-treated rats. In in-vitro studies, PMD did not affect PC12 cell survival at the maximal dose of 10 µM. In addition, PMD concentration-dependently prevents H₂O₂-induced neuronal death in PC12 cells. The in-silico docking analysis showed that the PMD fit snugly into the active site of human AChE by engaging with the anionic domain and the catalytic triad of Trp86, Tyr337, Phe338, and Gly121 residues. In conclusion, our study demonstrated that PMD have significant impact on AD by inhibiting ACheE and restoring neurotransmitter levels, which enhances Ach levels in rats and improves cognitive impairment in STZ rats.

Preconditioning of Mesenchymal Stem Cells Enhances the Neuroprotective Effects of Their Conditioned Medium in an Alzheimer's Disease In Vitro Model.

Alzheimer's disease (AD) develops as a result of oxidative damage to neurons and chronic inflammation of microglia. These processes can be influenced by the use of a conditioned medium (CM) derived from mesenchymal stem cells (MSCs). The CM contains a wide range of factors that have neurotrophic, antioxidant, and anti-inflammatory effects. In addition, the therapeutic potential of the CM can be further enhanced by pretreating the MSCs to increase their paracrine activity. The current study aimed to investigate the neuroprotective effects of CM derived from MSCs, which were either activated by a TLR3 ligand or exposed to CoCl2, a hypoxia mimetic (pCM or hCM, respectively), in an in vitro model of AD. We have developed a novel in vitro model of AD that allows us to investigate the neuroprotective and anti-inflammatory effects of MSCs on induced neurodegeneration in the PC12 cell line and the activation of microglia using THP-1 cells. This study demonstrates for the first time that pCM and hCM exhibit more pronounced immunosuppressive effects on proinflammatory M1 macrophages compared to CM derived from untreated MSCs (cCM). This may help prevent the development of neuroinflammation by balancing the M1 and M2 microglial phenotypes via the decreased secretion of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and increased secretion of IL-4, as well as the expression of IL-10 and TGF-β by macrophages. Moreover, a previously unknown increase in the neurotrophic properties of hCM was discovered, which led to an increase in the viability of neuron-like PC12 cells under H2O2-induced oxidative-stress conditions. These results are likely associated with an increase in the production of growth factors, including vascular endothelial growth factor (VEGF). In addition, the neuroprotective effects of CM from preconditioned MSCs are also mediated by the activation of the Nrf2/ARE pathway in PC12 cells. TLR3 activation in MSCs leads to more potent immunosuppressive effects of the CM against pro-inflammatory M1 macrophages, while the use of hCM led to increased neurotrophic effects after H2O2-induced damage to neuronal cells. These results are of interest for the potential treatment of AD with CM from preactivated MSCs.

Neuroprotective Effect of Codonopsis pilosula Polysaccharide on Aβ25-35-Induced Damage in PC12 Cells via the p38MAPK Signaling Pathways.

Plant polysaccharides have attracted increasing attention due to their high efficiency and low toxicity. Codonopsis pilosula polysaccharide (CPP) is an essential substance extracted from Codonopsis pilosula, known for its excellent antioxidant and neuroprotective effects. However, it is still unclear how CPP improves nerve protection and what its underlying molecular mechanisms are. This study aimed to investigate the neuroprotective effect of CPP on Aβ25-35-induced damage in PC12 cells and its underlying molecular mechanisms. The neuroprotective effect of CPP was evaluated using Aβ25-35-induced damage in pheochFfromocytoma (PC12) cells as an in vitro cell model. The cells were treated with CPP alone or in combination with SB203580 (an inhibitor of p38MAPK) in Aβ25-35 culture. The cell viability was assessed using a 3-(4,5-Dimethylthiazol-2-yl)-2,diphenyltetrazolium (MTT) assay. Furthermore, reactive oxygen species (ROS) were detected using flow cytometry. The production levels of intracellular superoxide dismutase (SOD), dismutase (SOD), glutathione (GSH), catalase (CAT), and malondialdehyFde (MDA) were determined using the colorimetric method. Annexin V-FITC and propidium iodide (PI) staining, as well as 33258 were performed using fluorescence microscopy. Moreover, the effect of adding SB203580 was studied to determine the changes in cell apoptosis induced by CPP treatment and Aβ25-35 induction. The CPP markedly inhibited Aβ25-35-induced reduction in the viability and apoptosis of PC12 cells. CPP also reduced the Aβ25-35-induced increase in the expression of the apoptosis factors and the levels of free radicals (ROS and MDA) and reversed the Aβ25-35-induced suppression of antioxidant activity. Additionally, inhibition of p38MAPK via the addition of their antagonists reversed the observed anti-apoptosis effects of CPP. CPP can efficiently provide neuroprotection against Aβ25-35-induced damage in PC12 cells brought about via oxidation and apoptosis reactions, and the underlying mechanisms involve the p38MAPK pathways. Therefore, CPP could potentially be useful as a neuroprotective agent in natural medicine, pharmacy, and the food industry.

Melastoma dodecandrum lour. Protects against cerebral ischemia–reperfusion injury by ameliorating oxidative stress and endoplasmic reticulum stress

Ethnopharmacological relevanceMelastoma dodecandrum Lour. (MD), a traditional Chinese medicine used by the She ethnic group, has been used to treat cerebral ischemia-reperfusion (CIR) injury due to its efficacy in promoting blood circulation and removing blood stasiss; however, the therapeutic effects and mechanisms of MD in treating CIR injury remain unclear. AimTo investigate the protective effects of MD on CIR injury, in addition to its impact on oxidative stress, endoplasmic reticulum (ER) stress, and cell apoptosis. Materials and methodsThe research was conducted using both cell experiments and animal experiments. The CCK-8 method, immunofluorescence staining, and flow cytometry were used to analyze the effects of MD-containing serum on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cell viability, reactive oxygen species (ROS) clearance, anti-inflammatory, neuroprotection and inhibition of apoptosis. Furthermore, 2,3,5-Triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, Nissl staining, and immunohistochemistry were used to detect infarct size, pathological changes, Nissl corpuscula and neuronal protein expression in middle cerebral artery occlusion (MCAO) rats. Polymerase chain reaction and Western Blotting were conducted in cell and animal experiments to detect the expression levels of ER stress-related genes and proteins. ResultsThe MD extract enhanced the viability of PC12 cells under OGD/R modeling, reduced ROS and IL-6 levels, increased MBP levels, and inhibited cell apoptosis. Furthermore, MD improved the infarct area in MCAO rats, increased the number of Nissl bodies, and regulated neuronal protein levels including Microtubule-Associated Protein 2 (MAP-2), Myelin Basic Protein (MBP), Glial Fibrillary Acidic Protein (GFAP), and Neurofilament 200 (NF200). Additionally, MD could regulate the expression levels of oxidative stress proteins malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT). Both cell and animal experiments demonstrated that MD could inhibit ER stress-related proteins (GRP78, ATF4, ATF6, CHOP) and reduce cell apoptosis. ConclusionThis study confirmed that the therapeutic mechanism of the MD extract on CIR injury was via the inhibition of oxidative stress and the ER stress pathway, in addition to the inhibition of apoptosis.

Gentiana capitata Buch.-Ham. ex D.Don Cell Suspension Culture as a New Source of Isosaponarin and 3,7,8-Trimethoxy-9-oxo-9H-xanthen-1-yl 6-O-β-D-ribopyranosyl-β-D-allopyranoside and Their Effect on PC-12 Cell Viability.

Some species of the Gentianaceae family are a valuable source of secondary metabolites. However, the phytochemical knowledge of some of these species remains insufficient. Therefore, this work focused on the isolation of the two main secondary metabolites in the methanolic extract from a Gentiana capitata cell suspension using preparative HPLC and the determination of their structure using UHPLC-DAD-IT-MS/MS and NMR methods. Their content in the methanolic extract was quantified using a previously validated HPLC method. The toxicity of the extract and two isolated compounds was also tested on the PC-12 cell line. The structures of the main secondary metabolites were identified as isosaponarin and 3,7,8-Trimethoxy-9-oxo-9H-xanthen-1-yl 6-O-β-D-ribopyranosyl-β-D-allopyranoside by comparing the UHPLC-DAD-IT-MS/MS and NMR results with the literature data. The content of isosaponarin was determined to be 0.76 ± 0.04%, and the content of 3,7,8-trimethoxy-9-oxo-9H-xanthen-1-yl 6-O-β-D-ribopyranosyl-β-D-allopyranoside was found to be 0.31 ± 0.02% in the dry extract. Additionally, a two-fold increase in the viability of the PC-12 cell line was observed compared to the control after treatment with the methanolic extract at a concentration of 500 µg/mL. These results suggest the potential use of G. capitata cell suspension methanolic extract as a new source of isosaponarin and 3,7,8-trimethoxy-9-oxo-9H-xanthen-1-yl 6-O-β-D-ribopyranosyl-β-D-allopyranoside, highlighting their lack of toxicity to the PC-12 (rat pheochromocytoma) cell line.

Anti-inflammatory and DNA Repair Effects of Astragaloside IV on PC12 Cells Damaged by Lipopolysaccharide.

This study aimed to establish a neural cell injury model in vitro by stimulating PC12 cells with lipopolysaccharide (LPS) and to examine the effects of astragaloside IV on key targets using high-throughput sequence technology and bioinformatics analyses. PC12 cells in the logarithmic growth phase were treated with LPS at final concentrations of 0.25, 0.5, 0.75, 1, and 1.25 mg/mL for 24 h. Cell morphology was evaluated, and cell survival rates were calculated. A neurocyte inflammatory model was established with LPS treatment, which reached a 50% cell survival rate. PC12 cells were treated with 0.01, 0.1, 1, 10, or 100 µmol/L astragaloside IV for 24 h. The concentration of astragaloside IV that did not affect the cell survival rate was selected as the treatment group for subsequent experiments. NOS activity was detected by colorimetry; the expression levels of ERCC2, XRCC4, XRCC2, TNF-α, IL-1β, TLR4, NOS and COX-2 mRNA and protein were detected by RT-qPCR and Western blotting. The differentially expressed genes (DEGs) between the groups were screened using a second-generation sequence (fold change>2, P<0.05) with the following KEGG enrichment analysis, RT-qPCR and Western blotting were used to detect the mRNA and protein expression of DEGs related to the IL-17 pathway in different groups of PC12 cells. The viability of PC12 cells was not altered by treatment with 0.01, 0.1, or 1 µmol/L astragaloside IV for 24 h (P>0.05). However, after treatment with 0.5, 0.75, 1, or 1.25 mg/mL LPS for 24 h, the viability steadily decreased (P<0.01). The mRNA and protein expression levels of ERCC2, XRCC4, XRCC2, TNF-α, IL-1β, TLR4, NOS, and COX-2 were significantly increased after PC12 cells were treated with 1 mg/mL LPS for 24 h (P<0.01); however, these changes were reversed when PC12 cells were pretreated with 0.01, 0.1, or 1 µmol/L astragaloside IV in PC12 cells and then treated with 1 mg/mL LPS for 24 h (P<0.05). Second-generation sequencing revealed that 1026 genes were upregulated, while 1287 genes were downregulated. The DEGs were associated with autophagy, TNF-α, interleukin-17, MAPK, P53, Toll-like receptor, and NOD-like receptor signaling pathways. Furthermore, PC12 cells treated with a 1 mg/mL LPS for 24 h exhibited increased mRNA and protein expression of CCL2, CCL11, CCL7, MMP3, and MMP10, which are associated with the IL-17 pathway. RT-qPCR and Western blotting analyses confirmed that the DEGs listed above corresponded to the sequence assay results. LPS can damage PC12 cells and cause inflammatory reactions in nerve cells and DNA damage. astragaloside IV plays an anti-inflammatory and DNA damage protective role and inhibits the IL-17 signaling pathway to exert a neuroprotective effect in vitro.

MiRNA-103-3p promotes neural cell autophagy by activating Wnt/β-catenin signaling via targeting rab10 in a rat model of depression

To explore the neuroprotective role of Rab10 gene in depression and the mechanism mediating its effect. Forty-eight male SD rats were randomized into a control group and 3 chronic unpredictable mild stress (CUMS) groups (n=12). The rats in the latter 3 groups were subjected to injections of normal saline, an adeno-associated viral (AAV) vector, or a Rab10-overexpressing AAV vector in the lateral ventricle after CUMS modeling. The depressive behavioral changes of the rats were assessed using behavioral tests. The TargetScan database was used to predict the miRNA interacting with Rab10 and the binding sites. The interaction between miRNA-103-3p and Rab10 was investigated using dual-luciferase and radioimmunoprecipitation (RIP) assay. The effect of corticosterone treatment on PC12 cell viability was assessed with CCK-8 assay. In corticosterone-stimulated PC12 cells, the changes in BDNF, CREB, p62, Beclin-1, Wnt3a, Gsk3β, phosphorylated (p)-Gsk3β, and β-catenin protein expressions following transfection with the Rab10-overexpressing AAV vector and a miRNA-103-3p inhibitor, alone or in combination, were analyzed using qRT-PCR and Western blotting. Injection of Rab10-overexpressing AVV vector into the lateral ventricle significantly improved depressive behaviors of CUMS rats. The mRNA and proteins expression of Rab10 were significantly down-regulated in the hippocampus of CUMS rats and in corticosteronestimulated PC12 cells. Bioinformatics analysis and the results of double luciferase and RIP experiments confirmed the targeting relationship between miRNA-103-3p and Rab10. In PC12 cells, overexpression of Rab10 or silencing miRNA-103-3p activated the Wnt/β-catenin signaling pathway, up-regulated the expressions of BDNF, CREB and Beclin-1, and down-regulated the expression of p62 protein; silencing Rab10 obviously blocked the effect of miRNA-103-3p inhibitor. In mouse models of depression, miRNA-103-3p activates Wnt/β-catenin signaling via targeting rab10 to improve neural plasticity and promotes neural cell autophagy.

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.

ADSCs encapsulated in Gelatin methacrylate substrate promotes the repair of peripheral nerve injury by SIRT6/PGC-1α pathway

Peripheral nerve injury is a prevalent disease but the spontaneous recovery of nerve function is protracted and incomplete. Given the damaging of stem cells and fragile of intra-neural structures in the course of stem cell transplantation, our study tried to investigate whether encapsulating adipose derived mesenchymal stem cells (ADSCs) with GelMA could achieve better repair in peripheral nerve injury. PC-12 cells were cultured on the surface of GelMA encapsulating ADSCs and 3D co-culture system was constructed. CCK-8, Real-Time PCR, ELISA, Immunofluorescent Assay and Western Blot were used to evaluate the functionality of this system. Ultimately, nerve conduit containing the 3D co-culture system was linked between the two ends of an injured nerve. ADSCs encapsulated in 5% GeIMA had a better activity than 10% GeIMA. Furthermore, the viability of PC-12 cells was also better in this 3D co-culture system than in co-culture system with ADSCs without GeIMA. The expression of SIRT6 and PGC-1α in PC-12 cells were prominently promoted, and the entry to nuclear of PGC-1α was more obvious in this 3D co-culture system. After silencing of SIRT6, the protein expression level of PGC-1α was inhibited, and the activity of PC-12 cells was significantly reduced, suggesting that ADSCs encapsulated in GelMA upregulated the expression of SIRT6 to induce the level of PGC-1α protein, thereby achieving an impact on the activity of PC-12 cells. In vivo, nerve conduit containing the 3D co-culture system significantly promoted the repair of damaged peripheral nerves. In conclusion, our study demonstrated that 5% GelMA enhanced ADSCs activity, thereby promoting the activity of nerve cells and repair of damaged peripheral nerves by SIRT6/PGC-1α pathway.

3'-Daidzein Sulfonate Sodium Protects against Glutamate-induced Neuronal Injuries by Regulating NMDA Receptors.

It was previously found that 3'-Daidzein Sulfonate Sodium (DSS) exhibits protective effects on cerebral ischemia/reperfusion injury (CI/RI). This study aimed to explore the underlying molecular mechanisms involved in the neuroprotective effects of DSS against ischemic stroke. In this study, rats with transient middle cerebral artery occlusion (tMCAO) were used as an in vivo model, whereas PC12 cells treated with glutamate alone and rat primary cortical neurons treated with the combination of glutamate and glycine were used as in vitro models. Cell viability and lactate dehydrogenase (LDH) release were used to evaluate cell injury. Cell apoptosis was determined by flow cytometry. Quantitative polymerase chain reaction (qPCR), Western blotting, and immunofluorescent staining methods were used to determine the mRNA expressions and protein levels and location. It was found that DSS significantly suppressed the impaired viability of PC12 cells induced by glutamate. DSS also increased cell viability while reducing the LDH release and apoptosis in primary cortical neurons injured by glutamate and glycine. In addition, DSS decreased GluN2B subunit expression while enhancing the expressions of GluN2A subunit and PSD95 in tMCAO rats' brains. This study demonstrated that DSS protects against excitotoxic damage in neurons induced by CI/RI through regulating the expression of NMDA receptors and PSD95. Our findings provide experimental evidence for the potential clinical administration of DSS in ischemic stroke.

Neuroprotective effects of Shaoyao Gancao decoction against excitatory damage in PC12 cells based on the Src-NR2-nNOS pathway

ObjectiveTo explore the neuroprotective effects of the Shaoyao Gancao decoction (SGD) against excitatory damage in PC12 cells and the role of the Src-NR2-nNOS pathway mediation by SGD in regulating γ-aminobutyric acid (GABA)-glutamate (Glu) homeostasis. MethodsN-Methyl-d-aspartic acid (NMDA) was used to establish a PC12 cell excitability injury model. To investigate the neuroprotective effect of SGD, a cell counting kit-8 (CCK-8) assay was used to determine PC12 cell viability, Annexin V/Propidium Iodide (Annexin V/PI) double staining was used to determine PC12 cell apoptosis, and Ca2+ concentration was observed using laser confocal microscopy. GABA receptor agonists and antagonists were used to analyze the neuroprotective interactions between γ-aminobutyric acid (GABA) and NMDA receptors. Additionally, molecular biology techniques were used to determine mRNA and protein expression in the Src-NR2-nNOS pathway. We analyzed the correlations between the regulatory sites of GABA and NMDA interactions, excitatory neurotoxicity, and brain damage at the molecular level. ResultsNMDA excitotoxic injury manifested as a significant decrease in cell activity, increased apoptosis and caspase-3 protein expression, and a significant increase in intracellular Ca2+ concentration. Administration of SGD, a GABAA receptor agonist (muscimol), or a GABAB receptor agonist (baclofen) decreased intracellular Ca2+ concentrations, attenuated apoptosis, and reversed NMDA-induced upregulation of caspase-3, Src, NMDAR2A, NMDAR2B, and nNOS. Unexpectedly, a GABAA receptor antagonist (bicuculline) and a GABAB receptor antagonist (saclofen) failed to significantly increase excitatory neurotoxicity. ConclusionsTaken together, these results not only provide an experimental basis for SGD administration in the clinical treatment of central nervous system injury diseases, but also suggest that the Src-NR2A-nNOS pathway may be a valuable target in excitotoxicity treatment.

Wired for Success: Probing the Effect of Tissue-Engineered Neural Interface Substrates on Cell Viability.

This study investigates the electrochemical behavior of GelMA-based hydrogels and their interactions with PC12 neural cells under electrical stimulation in the presence of conducting substrates. Focusing on indium tin oxide (ITO), platinum, and gold mylar substrates supporting conductive scaffolds composed of hydrogel, graphene oxide, and gold nanorods, we explored how the substrate materials affect scaffold conductivity and cell viability. We examined the impact of an optimized electrical stimulation protocol on the PC12 cell viability. According to our findings, substrate selection significantly influences conductive hydrogel behavior, affecting cell viability and proliferation as a result. In particular, the ITO substrates were found to provide the best support for cell viability with an average of at least three times higher metabolic activity compared to platinum and gold mylar substrates over a 7 day stimulation period. The study offers new insights into substrate selection as a platform for neural cell stimulation and underscores the critical role of substrate materials in optimizing the efficacy of neural interfaces for biomedical applications. In addition to extending existing work, this study provides a robust platform for future explorations aimed at tailoring the full potential of tissue-engineered neural interfaces.

Ultrastructural Changes of Neuroendocrine Pheochromocytoma Cell Line PC-12 Exposed In Vitro to Rotenone.

Rotenone is a pesticide used in research for its ability to induce changes similar, in vivo and in vitro, to those observed in Parkinson's disease (PD). This includes a selective death of dopaminergic neurons in the substantia nigra. Nonetheless, the precise mechanism through which rotenone modifies structure and function of neurons remains unclear. The PC12 cells closely resemble dopamine terminal neurons. This makes it a preferred model for studying the morphology of central dopamine neurons and predicting neurotoxicity. In this paper, we investigated the effects of 0.5 µM rotenone for 24-48 h on PC12 cell viability and ultrastructure (TEM), trying to identify primary and more evident alterations that can be related to neuronal damages similar to that seen in animal PD models. Cell viability decreased after 24 h rotenone treatment, with a further decrease after 48 h. Ultrastructural changes included vacuolar degeneration, mitochondrial mild swelling, decrease in the number of neuropeptide granules, and the loss of cell-to-cell adhesion. These findings are in agreement with previous research suggesting that rotenone, by inhibiting energy production and increasing ROS generation, is responsible for significant alterations of the ultrastructure and cell death of PC12 cells. Our data confirm the link between rotenone exposure, neuronal damage, and changes in dopamine metabolism, suggesting its role in the pathogenesis of PD.

Iridoids rich fraction from Valeriana jatamansi Jones promotes axonal regeneration and motor functional recovery after spinal cord injury through activation of the PI3K/Akt signaling pathway.

Valeriana jatamansi Jones (VJJ), renowned for its extensive history in traditional Chinese medicine and ethnomedicine within China, is prevalently utilized to alleviate ailments such as epigastric distension and pain, gastrointestinal disturbances including food accumulation, diarrhea, and dysentery, as well as insomnia and other diseases. Moreover, the Iridoid-rich fraction derived from Valeriana jatamansi Jones (IRFV) has demonstrated efficacy in facilitating the recuperation of motor functions after spinal cord injury (SCI). This study is aimed to investigate the therapeutic effect of IRFV on SCI and its underlying mechanism. Initially, a rat model of SCI was developed to assess the impact of IRFV on axonal regeneration. Subsequently, employing the PC12 cell model of oxidative damage, the role and mechanism of IRFV in enhancing axonal regeneration were explored using the phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway inhibitor LY294002. Ultimately, the same inhibitor was administered to SCI rats to confirm the molecular mechanism through which IRFV promotes axonal regeneration by activating the PI3K/Akt signaling pathway. The results showed that IRFV significantly enhanced motor function recovery, reduced pathological injury, and facilitated axonal regeneration in SCI rats. In vitro experiments revealed that IRFV improved PC12 cell viability, augmented axonal regeneration, and activated the PI3K/Akt signaling pathway. Notably, the inhibition of this pathway negated the therapeutic benefits of IRFV in SCI rats. In conclusion, IRFV promote promotes axonal regeneration and recovery of motor function after SCI through activation of the PI3K/Akt signaling pathway.

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.