Autophagy induction by hispidulin provides protection against sevoflurane-induced neuronal apoptosis in aged rats

Effect of the Proximity to the Quintero-Puchuncaví Industrial Zone on Compounds Isolated from Baccharis macraei Hook. & Arn: Their Antioxidant and Cytotoxic Activity

Baccharis macraei Hook. & Arn (Asteraceae), commonly known as Vautro, is found in the coastal areas of central-southern Chile, including the industrial zone of Quintero-Puchuncaví, known for the contamination of its soils with heavy metals, which together with other factors generate abiotic stress in plant species, against which they present defensive mechanisms. For this reason, the objective was to evaluate the effect of abiotic stress generated by the proximity of B. macraei to the industrial complex by assessing the physiological and metabolic states reported by the extracts and compounds isolated from the species, as well as the photosynthetic capacity, metal content and production, and antioxidant activity and cytotoxicity against tumorigenic cell lines of the phytoconstituents. To this end, B. macraei was collected at two different distances from the industrial complex, observing that the closer the species is, the greater the concentration of copper in the soil, generating a decrease in the rate of electron transport in situ, but an increase in antioxidant activity with low cytotoxicity. This activity could be due to the presence of flavonoids such as Hispidulin, Cirsimaritina, and Isokaempferida, as well as monoterpenes, oxygenated and non-oxygenated sesquiterpenes identified in this study.

Exogenous recombinant Hsp70 attenuates sevoflurane anesthesia-induced cognitive dysfunction in aged mice

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a severe postoperative neurological sequela in elderly patients, and there is currently no standard treatment for POCD. In this study, whether recombinant human heat shock protein 70 (rHsp70) could alleviate sevoflurane-induced cognitive impairment in aged mice is investigated.

METHODS

To determine the prophylactic effect of rHsp70 in sevoflurane-induced cognitive dysfunction, aged mice were pretreated with different concentrations of rHsp70 (29.4, 58.8, and 117.6 μg/kg; intranasal injected; N = 12) every day for 1 week; then, 3% sevoflurane was utilized to anesthetize the aged mice. Cognitive function, neurotoxicity, and serum and hippocampal Hsp70 levels in aged mice undergoing sevoflurane anesthesia were assessed by the Morris water maze test and enzyme-linked immunosorbent assay. The effects of rHsp70 on inflammatory response were assessed by proinflammatory cytokine production and nuclear factor-κB (NF-κB) activation assays.

RESULTS

We found that aged mice exposed to sevoflurane showed reduced learning and memory ability and reduced Hsp70 expression, which were both restored by rHsp70 pretreatment. RHsp70 also reversed sevoflurane-induced up-regulated Bax and Bcl-2 expression and interleukin-1, IL-6, and monocyte chemoattractant protein-1 overproduction. Finally, rHsp70 pretreatment suppressed sevoflurane-induced NF-κB activation. Our study indicated that rHsp70 was sufficient to suppress sevoflurane-induced cognitive decline and neurotoxicity.

CONCLUSION

Our important finding warrants further study on the clinical application of rHsp70 in elderly patients undergoing anesthesia.

microRNA-140-3p protects hippocampal neuron against pyroptosis to attenuate sevoflurane inhalation-induced post-operative cognitive dysfunction in rats via activation of HTR2A/ERK/Nrf2 axis by targeting DNMT1

The incidence of post-operative cognitive dysfunction (POCD) remains a relatively prevalent complication in the elderly after surgery, especially in those receiving sevoflurane (Sevo) anesthesia. microRNA (miR)-140-3p has been demonstrated to orchestrate neuroinflammation and neuron apoptosis. However, the role of miR-140-3p in POCD remains largely unknown. In this context, this research was designed to explore whether miR-140-3p mediated Sevo inhalation-induced POCD in rats. A POCD rat model was established by Sevo inhalation, and a Sevo cell model was constructed in primary hippocampal neurons isolated from rats, followed by detection of miR-140-30 and HTR2A expression. Then, gain- and loss-of-function assays were implemented in rats and neurons. In rats, the cognitive function was evaluated by Water maze test and step-through test, and neuron apoptosis by TUNEL staining. In neurons, cell viability, apoptosis, and pyroptosis-related factors were tested by MTT, flow cytometry, and Western blot analysis respectively. Interaction between HTR2A and DNMT1 was assessed by MSP, and ChIP assay, and interaction between miR-140-3p and DNMT1 by dual-luciferase reporter assay, RIP and RNA pull-down. HTR2A and miR-140-3p were downregulated in POCD rats and Sevo-treated hippocampal neurons. Mechanistically, miR-140-3p negatively targeted DNMT1 to decrease HTR2A promoter methylation, thus upregulation HTR2A to activate ERK/Nrf2 pathway. miR-140-3p or HTR2A overexpression or activation of ERK/Nrf2 pathway elevated neuron viability and diminished their apoptosis and pyroptosis while alleviating Sevo-induced POCD in rats. Collectively, miR-140-3p might repress neuron pyroptosis to alleviate Sevo inhalation-induced POCD in rats via DNMT1/HTR2A/ERK/Nrf2 axis.

4.8% sevoflurane induces activation of autophagy in human neuroblastoma SH-SY5Y cells by the AMPK/mTOR signaling pathway

Prolonged sevoflurane exposure leads to neurotoxicity. Autophagy plays an important role in promoting cell survival in different conditions. However, the role and mechanism of autophagy in sevoflurane-induced neurotoxicity were not fully elucidated. We attempted to indicate whether sevoflurane could activate the AMP-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR)-mediated autophagy to attenuate anesthetics-induced neuronal injury in this study. Sevoflurane treatment significantly decreased the cell viability and induced apoptosis of SH-SY5Y cells. The expression level of Bcl-2 decreased, while that of Bax remarkably increased. Meanwhile, autophagy was activated by sevoflurane exposure as evidenced by increased expression levels of autophagy-related proteins (LC3-II and Atg5), decreased expression level of autophagic substrate P62, and increased autophagosomes and autolysosomes. Further autophagosomes and fewer autolysosomes were observed in the presence of Bafilomycin A1, an autolysosomes degradation inhibitor, suggesting that sevoflurane induced autophagic flux rather than inhibiting degradation of autophagy. Activation of autophagy by rapamycin partly reversed the sevoflurane-decreased cell viability. In contrast, inhibition of autophagy by 3-Methyladenine (3-MA) or Atg5-targeted small interfering RNA (siRNA) aggravated the sevoflurane-induced neurotoxicity. Further examination revealed that sevoflurane-induced autophagy was mediated by the AMPK/mTOR signaling pathway, with increased p-AMPK expression and decreased p-mTOR expression. Collectively, these results indicated that sevoflurane activates autophagy by regulating the AMPK/mTOR signaling pathway, which is protective against sevoflurane-induced damage in SH-SY5Y cells. Our results may assist clinicians to develop further promising therapeutic strategies for the neurotoxicity induced by inhaled anesthetics.

Hispidulin Ameliorates Endotoxin-Induced Acute Kidney Injury in Mice

Lipopolysaccharide (LPS) is an endotoxin that plays a crucial role in septic acute kidney injury (AKI). Hispidulin is a natural flavonoid that possesses various biological activities. Recent studies have shown that hispidulin administration alleviates various inflammatory diseases in animal models. This study aimed to investigate the renoprotective effect of hispidulin on LPS-induced AKI. Male C57BL/6 mice were administered LPS (10 mg/kg) with or without hispidulin (50 mg/kg). Hispidulin administration attenuated renal dysfunction, histological alterations, and the upregulation of neutrophil gelatinase-associated lipocalin. This flavonoid also reduced cytokine production and Toll-like receptor 4 expression, inhibited nuclear factor-κB and mitogen-activated protein kinase cascades, and alleviated immune cell infiltration. The oxidation of lipids and DNA was also inhibited by hispidulin administration. This antioxidant effect of hispidulin was associated with the downregulation of NADPH oxidase 4, the activation of catalase and superoxide dismutase activities, and the restoration of glutathione levels. Moreover, hispidulin administration attenuated tubular cell apoptosis by inhibiting caspase-3 pathway. These data suggest that hispidulin ameliorates endotoxin-induced kidney injury by suppressing inflammation, oxidative stress, and tubular cell death.

Hypercholesterolemia aggravates sevoflurane-induced cognitive impairment in aged rats by inducing neurological inflammation and apoptosis

We aimed to explore the effects of hypercholesterolemia on sevoflurane-induced cognitive impairment in aged rats and the underlying mechanism(s). Aged rats were administrated with high-fat diet, sevoflurane, or both. Thereafter, the plasma levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were evaluated. The Morris water maze task was performed to evaluate the spatial learning and memory ability of rats. Moreover, Nissl and Evans blue staining were conducted to test nerve damage and detect the blood-brain barrier permeability, respectively. The percentage of apoptotic cells was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The messenger RNA expression of inflammatory factors and protein expression of microglial activation markers and apoptosis-related proteins were tested by real-time polymerase chain reaction, enzyme-linked immunosorbent assay, or western blot analysis, respectively. High-fat diet induced high levels of TC, TG, and LDL but decreased levels of HDL. However, sevoflurane had no effects on these levels. In contrast, sevoflurane significantly induced the impairment of learning and memory, nerve damage, neuroinflammatory damage, and neuronal apoptosis. Hypercholesterolemia exacerbated the sevoflurane-induced impairment in aged rats. These results suggested that hypercholesterolemia aggravates sevoflurane-induced cognitive impairment in aged rats, possibly by inducing neurological inflammation and apoptosis.

Protective Effects of the Hydroethanolic Extract of Fridericia chica on Undifferentiated Human Neuroblastoma Cells Exposed to α-Zearalenol (α-ZEL) and β-Zearalenol (β-ZEL)

Fridericia chica (Bignoniaceae) is a traditional medicinal plant. The aim of this research was to determine the protective effects of the hydroethanolic extract from the F. chica leaves (HEFc) against the cytotoxicity of zearalenone (α-ZEL) and β-ZEL on SH-SY5Y cells. Free radical scavenging activity of HEFc was evaluated using the DPPH method. The cytotoxicity of both zearalenone metabolites and HEFc was examined using MTT test, as was the cytoprotective effects of the HEFc on cells treated with these mycotoxins. The chemical composition of HEFc was determined using UPLC-QTOF-MS/MS. HEFc elicited good DPPH radical scavenging activity following a concentration-dependent relationship. Cells exposed to α-ZEL exhibited a viability ˂50% after 48 h of treatment (25 and 50 µM), while those exposed to β-ZEL showed viability ˂50% (100 µM) and ˂25% (25-100 µM) after 24 and 48 h of exposure, respectively. HEFc showed a significant increase in cell viability after exposure to α-ZEL (25 and 50 µM) and β-ZEL (6-100 µM) (p < 0.05). UPLC-QTOF-MS/MS analyses allowed the identification of 10 phytochemical components in the HEFc. In short, the hydroethanolic extract of F. chica grown in Colombian Caribbean can protect against the effects of mycotoxins and it is a valuable source of compounds with antioxidant properties.

Amelioration effects of Cirsium japonicum var. maackii extract/fractions on amyloid beta25-35-induced neurotoxicity in SH-SY5Y cells and identification of the main bioactive compound

Amyloid beta (Aβ) is a neurotoxic peptide, and the accumulation of Aβ in the brain is the major characteristic of Alzheimer's disease (AD). Recently, the beneficial effects of Cirsium japonicum var. maackii (CJM) on brain health has attracted much attention. In the present study, we investigated the ability and protective mechanisms of CJM to attenuate neuronal toxicity caused by Aβ using SH-SY5Y cells. Aβ25-35 treatment decreased cell viability, whereas CJM extract/fractions increased cell viability in Aβ25-35-treated cells. We found that CJM treatment prevented the accumulation of reactive oxygen species observed in Aβ25-35-treated control cells. Furthermore, Aβ25-35-mediated production of inflammatory cytokines such as interleukin-1β was significantly suppressed by CJM. In addition, apoptotic factors were modulated in CJM-treated cells by downregulating B-cell lymphoma-2-associated X protein and upregulating B-cell lymphoma-2 protein expression. The assays showed that the ethyl acetate (EtOAc) fraction of CJM has greater neuroprotective bioactivities compared with the other extract/fractions. The main neuroprotective active compound from the EtOAc fraction of CJM was identified as pectolinarin using ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry. Collectively, this study not only describes the neuroprotective effect of CJM against Aβ25-35via the regulation of oxidative, inflammatory, and apoptotic signaling pathways, but also provides useful information for future studies on the mechanism of novel medicinal sources based on pectolinarin isolated from CJM.

Hesperidin alleviates bupivacaine anesthesia-induced neurotoxicity in SH-SY5Y cells by regulating apoptosis and oxidative damage

Local anesthetic with bupivacaine (BV) administration may cause severe neurotoxicity and neurological complications in developing neurons. Any substances that can mitigate the toxic effects of BV are of great importance in surgical procedures and pain management. The present study attempted to investigate if hesperidin (HN) could inhibit or prevent BV-induced neurotoxicity in SH-SY5Y cells. Exposure of BV at 5 mM resulted in a significant decrease of cell viability and a remarkable increase of lactate dehydrogenase release via the induction of apoptosis and production of reactive oxygen species. Moreover, a loss of mitochondrial membrane potential, decreased Bcl-2 protein expression, as well as increased expression of cytoplasmic cytochrome c, Bax, and cleaved caspase-3 protein was also observed in BV-stimulated SH-SY5Y cells. In addition, BV stimulation impaired the balance of oxidation-reduction and inflammation system, as evidenced by the increased malondialdehyde content, decreased superoxide dismutase and catalase activity, and reduced level of reduced glutathione, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α. However, these iatrogenic changes were all reversed by the HN (5, 10, and 20 μM) supplement for 48 h in a concentration-dependent manner. In conclusion, HN can protect SH-SY5Y cells against BV-stimulated neurotoxicity via the inhibition of apoptosis, oxidative stress, and inflammation response. The present findings suggested that HN may be an effective alternative agent to inhibit or prevent BV-induced neurotoxicity in human patients.

LncRNA-mRNA Expression Profiles and Functional Networks Associated with Cognitive Impairment in Folate-deficient Mice

BACKGROUND

Cognitive impairment is a common neurocognitive disorder that affects millions of worldwide people's health,related tofolate deficiency.

OBJECTIVE

The present study aimed to investigate the lncRNA-mRNA functional networks associated with cognitive impairment in folate-deficient mice and elucidate their possible molecular mechanisms.

METHODS

We downloaded the gene expression profile (GSE148126) of lncRNAs and mRNAs from NCBI Gene Expression Omnibus (GEO) database. Four groups of mouse hippocampi were analyzed, including 4 months (4mo) and 18 months (18mo) of folic acid (FA) deficiency/supplementation. The differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) were identified using gplots and heatmap packages. The functions of the DEmRNAs were evaluated using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The hub genes wereidentified by CytoHubba plugins of Cytoscape, and protein-protein interaction (PPI) network of deregulated mRNAs was performed using STRING database. Finally, lncRNA-mRNA co-expression and competitive endogenous RNA (ceRNA) network analyses were constructed.

RESULTS

In total, we screened 67 lncRNAs with 211 mRNAs, and 89 lncRNAs with 229 mRNAs were differentially expressed in 4mo_FAand 18mo_FA deficient mice, respectively. GO analyses indicated that DEmRNAs were highly related to terms involved in binding and biological regulation. KEGG pathway analyses demonstrated that these genes were significantly enriched for Renin secretion, Pancreatic secretion and AMPK signaling pathways in 18mo_FA deficiency group. Subsequently, the top 5 hub genes werescreened from the PPI network, which may be key genes with the progression of folate deficiency. Upon the lncRNA-mRNA co-expression network analysis, we identified the top 10 lncRNAs having the maximum number of connections with related mRNAs. Finally, a ceRNA network was constructed for DE lncRNAs and DEmRNAs, and several pivotal miRNAs were predicted.

CONCLUSIONS

This study identified the lncRNA-mRNA expression profiles and functional networks associated with cognitive impairment in folate-deficient mice, which provided support for the possible mechanisms and therapy for this disease.

The antiaging property of aqueous extract of Millingtonia hortensis flowers in aging neuron

Cellular senescence is the key mediator of cellular dysfunction before undergoing degenerative disease such as Alzheimer's disease. The aging process was mainly by the overactivation of senescence associated β-galactosidase (SA-β-gal) enzyme before mediated several negative responses, including intracellular reactive oxygen species (ROS) production, cellular senescence regulation, and death prior encourage synaptic loss. Thus, in the recent work, we evaluated the in vitro effects of aqueous extract of Millingtonia hortensis L. (MH) from flower in hydrogen peroxide (H₂O₂)-induced senescence in SK-N-SH cells. Herein, we demonstrated that MH significantly increased cell viability and decreased both of apoptotic cells and ROS production in a dose-dependent manner comparing to aging group (P < 0.01) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry, and ROS assay. Furthermore, the number of SA-β-gal-positive cells was also reduced in MH treatment (P < 0.01) together with the promotion of Sirt-1 protein. Importantly, MH also promoted the synaptic plasticity by decreased acetylcholinesterase activity and increased synaptophysin expression in aging neurons comparing to aging group (P < 0.01). Hispidulin (the active ingredient in MH) was also revealed the similarly effects to MH. Therefore, we suggested that MH might be beneficially for neurodegenerative disease that caused by aging.

Targeting pyroptosis to regulate ischemic stroke injury: Molecular mechanisms and preclinical evidences

Stroke is one of the leading causes of death worldwide with limited therapies. After ischemic stroke occurs, a robust sterile inflammatory response happens and lasts for days and determines neurological prognosis. Pyroptosis is an inflammatory programmed cell death characterized by cleavage of pore-forming proteins gasdermins as a result of activating caspases and inflammasomes. It has morphological characteristics of rapid plasma-membrane rupture and release of proinflammatory intracellular contents as well as cytokines. Recent researches implicate pyroptosis involvement in the pathogenesis of ischemic stroke and inhibition of pyroptosis attenuates ischemic brain injury. In this review, we discussed molecular mechanisms of pyroptosis, evidences for pyroptosis involvement in different kinds of the central nervous system cells, as well as potential inhibitors for intervention of pyroptosis. Based on the review, we hypothesize the feasibility of therapeutic strategies targeting pyroptosis in the context of ischemic stroke.

Mitophagy impairment is involved in sevoflurane-induced cognitive dysfunction in aged rats

Postoperative cognitive dysfunction (POCD) is frequently observed in elderly patients following anesthesia, but its pathophysiological mechanisms have not been fully elucidated. Sevoflurane was reported to repress autophagy in aged rat neurons; however, the role of mitophagy, which is crucial for the control of mitochondrial quality and neuronal health, in sevoflurane-induced POCD in aged rats remains undetermined. Therefore, this study investigated whether mitophagy impairment is involved in sevoflurane-induced cognitive dysfunction. We found sevoflurane treatment inhibited mitochondrial respiration and mitophagic flux, changes in mitochondria morphology, impaired lysosomal acidification, and increased Tomm20 and deceased LAMP1 accumulation were observed in H4 cell and aged rat models. Rapamycin counteracted ROS induced by sevoflurane, restored mitophagy and improved mitochondrial function. Furthermore, rapamycin ameliorated the cognitive deficits observed in aged rats given sevoflurane anesthesia as determined by the Morris water maze test; this improvement was associated with an increased number of dendritic spines and pyramidal neurons. Overexpression of PARK2, but not mutant PARK2 lacking enzyme activity, in H4 cells decreased ROS and Tomm20 accumulation and reversed mitophagy dysfunction after sevoflurane treatment. These findings suggest that mitophagy dysfunction could be a mechanism underlying sevoflurane-induced POCD and that activating mitophagy may provide a new strategy to rescue cognitive deficits.

Hispidulin: A promising flavonoid with diverse anti-cancer properties

In recent years, natural products have increasingly attracted more attention because of their potential anticancer activity and low intrinsic toxicity. Hispidulin is a natural flavonoid with a wide range of biological activities, including anti-inflammatory, antifungal, antiplatelet, anticonvulsant, anti-osteoporotic, and notably anticancer activities. Numerous in vivo and in vitro studies have shown that hispidulin, as a potential anticancer drug, affects cell proliferation, apoptosis, cell cycle, angiogenesis, and metastasis. Moreover, hispidulin exhibits synergistic anti-tumor effects when combined with some common clinical anticancer drugs (e.g., gemcitabine, 5-fluoroucil, sunitinib, temozolomide, and TRAIL). The combination of hispidulin and chemotherapeutic drugs reduces the efflux of chemotherapeutic drugs, enhances the chemosensitivity of cancer cells, and reverses drug resistance. Herein, we outlined the anticancer effects of hispidulin in various cancers and its intracellular molecular targets and related mechanisms of its anticancer activity. Based on the available literature, it can be established that hispidulin has significant potential to become an important complementary medicine for cancer prevention and treatment. However, more in-depth in vitro and in vivo studies should be conducted to support its translation from bench to bedside.

Autophagic Network Analysis of the Dual Effect of Sevoflurane on Neurons Associated with GABARAPL1 and 2

Background

Sevoflurane is commonly used as a general anesthetic in neonates to aged patients. Preconditioning or postconditioning with sevoflurane protects neurons from excitotoxic injury. Conversely, sevoflurane exposure induces neurotoxicity during early or late life. However, little is known about the underlying mechanism of the dual effect of sevoflurane on neurons. Autophagy is believed to control neuronal homeostasis. We hypothesized that autophagy determined the dual effect of sevoflurane on neurons.

Methods

DTome was used to identify the direct protein target (DPT) of sevoflurane. The STRING database was employed to investigate the proteins associated with the DPTs. Protein-protein interaction was assessed using Cytoscape. WebGestalt was used to analyze gene set enrichment. The linkage between candidate genes and autophagy was identified using GeneCards.

Results

This study found that 23 essential DPTs of sevoflurane interacted with 77 proteins from the STRING database. GABARAPL1 and 2, both of which are DPT- and autophagy-associated proteins, were significantly expressed in the brain and enriched in GABAergic synapses.

Conclusions

Taken together, our findings showed that the network of sevoflurane-DPT-GABARAPL1 and 2 is related to the dual effect of sevoflurane on neurons.

Impact of Sevoflurane Versus Propofol Anesthesia on Post-Operative Cognitive Dysfunction in Elderly Cancer Patients: A Double-Blinded Randomized Controlled Trial

Background

Research on the clinical outcomes of surgical patients anaesthetized with sevoflurane and the association of sevoflurane with post-operative cognitive dysfunction (POCD) is scarce. We evaluated whether sevoflurane-based anesthesia increased the incidence of POCD and worsened prognosis compared to propofol-based anesthesia in elderly cancer patients.

Material/Methods

This single-center, prospective, double-blind randomized controlled trial included 234 patients aged 65 to 86 years undergoing tumor resection who received sevoflurane-based (Group S) or propofol-based (Group P) anesthesia during surgery. A series of neuropsychological tests was performed to evaluate cognitive function before surgery and at 7 days and 3 months post-operation, and the results were compared to those of healthy controls.

Results

At 7 days post-operation there were no significant differences in the incidence of POCD between patients who received sevoflurane-based or propofol-based anesthesia during surgery: Group S was at 29.1% (32 out of 110 patients) versus Group P at 27.3% (30 out of 110), P=0.764. At 3 months, Group S was at 11.3% (12 out of 106 patients) versus Group P at 9.2% (10 out of 109), P=0.604. During the first 2 days post-operation, the QoR-40 global score was significantly lower in Group S compared to Group P [POD 1: P=0.004; POD 2: P=0.001]. There were no significant differences in in-hospital post-operative complications, post-operative length of hospital stay, all-cause mortality at 30 days, and 3 months post-operation, or post-operative quality of life at 3 months between patients in Group S and Group P.

Conclusions

Sevoflurane-based anesthesia did not increase the incidence of POCD compared to propofol-based anesthesia at 7 days or 3 months post-operation or impact short-term post-operative prognosis.

Soyasapogenol B Attenuates Laryngeal Carcinoma Progression through Inducing Apoptotic and Autophagic Cell Death

Soyasapogenol B (Soy B), a constituent of soybean, has been shown to exhibit antitumor activities against different types of cancers. However, to our knowledge, no studies so far have investigated the effect of Soy B in human laryngeal carcinoma. This study, therefore, aimed to determine the effect of Soy B in human laryngeal carcinoma cell lines HeP-2 and TU212 and to elucidate the possible underlying mechanisms by which Soy B can induce its antitumor effects. The results showed that Soy B effectively attenuated the cell growth by causing G0/G1 phase cell cycle arrest in laryngeal carcinoma cell lines. Moreover, the percentage of apoptotic and autophagic cells dramatically increased upon exposure to Soy B. Western blotting results confirmed that Soy B can alter the expression levels of established markers of apoptosis and autophagy. Interestingly, both apoptosis inhibitor (ZVAD-fmk) and autophagy inhibitor (3-MA) could partially reverse the effect of Soy B, while blocking autophagy did not cause obvious alteration in the percentage of apoptotic cells. Similarly, in vivo studies validated that Soy B could effectively reduce the size of the tumor and induce apoptosis and autophagy in tumor tissues. Collectively, these results suggested that Soy B can exert anticancer activities against laryngeal carcinoma through inducing apoptotic and autophagic cell death. Our study highlighted the potential role of Soy B as a chemotherapeutic agent for laryngeal carcinoma. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1851-1858, 2020. © 2019 American Association for Anatomy.

Rapamycin improves sevoflurane‑induced cognitive dysfunction in aged rats by mediating autophagy through the TLR4/MyD88/NF‑κB signaling pathway

The present study was aimed to observe the protective effect of rapamycin on cognitive dysfunction induced by sevoflurane in aged rats and its effect on autophagy-related proteins, and to investigate the regulatory mechanism of the Toll-like receptor 4/myeloid differentiation primary response 88/nuclear factor-κB (TLR4/MyD88/NF-κB) signaling pathway. Fifty Sprague-Dawley rats were randomly assigned to a control group, a sevoflurane group, a rapamycin pretreatment group, a TLR4 inhibitor group and a 3MA autophagy inhibitor group. A water maze test was used to evaluate the cognition and memory of rats. Hematoxylin and eosin (H&E) staining was performed to observe pathological changes of brain tissue. A TUNEL assay was used to detect the apoptosis of brain tissue. ELISA was used to assess changes in brain injury markers and inflammatory factors. A western blot assay or quantitative reverse transcription PCR (RT-qPCR) were performed to determine the expression of autophagy-related proteins and the TLR4/MyD88/NF-κB signaling pathway in brain tissue. The results revealed that rapamycin could improve cognitive dysfunction of aged rats induced by sevoflurane. Rapamycin was identified to play a therapeutic role, including mitigating brain tissue damage, inhibiting apoptosis, and activating autophagy in a sevoflurane-treated aged rat model. This function of rapamycin was demonstrated to depend on the TLR4/MyD88/NF-κB signaling pathway.

Dexmedetomidine suppresses sevoflurane anesthesia-induced neuroinflammation through activation of the PI3K/Akt/mTOR pathway

Background

Sevoflurane, an inhalational general anesthetic, has become one of the most widely used inhalational anesthetics in surgery. However, previous studies have found that sevoflurane anesthesia can trigger an inflammatory response, resulting in secondary damage. Dexmedetomidine (DEX), a highly-selective α adrenergic receptor agonist, is widely used as an anesthetic adjuvant in the clinic. In this study we investigated whether DEX was able to suppress sevoflurane-induced neuroinflammation.

Methods

The aim was to determine the mechanism of action of the suppressive effect of DEX using a rat model. Rats were randomly divided into a control group (n = 10), low-dose sevoflurane group (L-Sev; n = 10), high-dose sevoflurane group (H-Sev; n = 10), vehicle group (n = 10), DEX group (n = 10) and DEX + LY294002 (a specific inhibitor of PI3K) group (n = 10). The rats in vehicle, DEX and DEX + LY294002 groups were in the presence of high-dose sevoflurane exposure. Western blotting was used to measure the expression of proinflammatory cytokines (IL-6, IL-8, TNF-α) and the activity level of the phosphatidylinositol 3-hydroxy kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway.

Results

We found that sevoflurane anesthesia induced an increase in the levels of pro-inflammatory cytokines, while decreasing activation of the PI3K/Akt/mTOR pathway in both the cortex and hippocampus of rats. Treatment with DEX reduced pro-inflammatory cytokine levels and prevented inactivation of the PI3K/Akt/mTOR pathway. Moreover, LY294002, an inhibitor of the PI3K/Akt/mTOR pathway, reduced the anti-inflammatory activity of DEX.

Conclusions

These data suggest that the PI3K/Akt/mTOR pathway contributes to sevoflurane-induced neuroinflammation and that activation of PI3K/Akt/mTOR signaling by DEX could help reduce the neuroinflammatory effects of sevoflurane.

Hispidulin exhibits neuroprotective activities against cerebral ischemia reperfusion injury through suppressing NLRP3-mediated pyroptosis

AIM

Ischemia/reperfusion (I/R) injury is the major cause of neurological deficit following stroke. Our previous study showed neuroprotective effects of hispidulin against cerebral ischemia reperfusion injury (IRI). In this study, we further examined the involvement of pyroptosis in this neuroprotective function.

MATERIALS AND METHODS

IRI was simulated in a rat model by middle cerebral artery occlusion (MCAO) surgery, and the animals were treated with different doses of hispidulin. The neurological function of the rats was evaluated by the neural function defect score (NFDS), balance beam test and limb placement test. The infarct volume and brain water content were measured 72 h following IRI. Neuronal cell survival and pyroptosis in the ischemic cortex were respectively detected by Nissl staining and TUNEL assay. The relative expression of pyroptosis markers was determined by qRT-PCR, Western blotting and ELISA as appropriate. IRI was simulated in vitro in primary cerebral astrocytes using the OGD/R procedure. AMPKα was blocked genetically or pharmacologically using siRNA and compound C respectively. CCK-8 and LDH release assays were performed using suitable kits.

RESULTS

Hispidulin improved the neurological symptoms of the rats after IRI, in addition to decreasing the infarct size and brain edema. Mechanistically, hispidulin exerted its neuroprotective effects in vivo and in vitro by suppressing NLRP3-mediated pyroptosis by modulating the AMPK/GSK3β signaling pathway.

CONCLUSION

Hispidulin is a neuroprotective agent with clinical potential against IR-induced neurological injury.

Moderate hypothermia protects increased neuronal autophagy via activation of extracellular signal-regulated kinase signaling pathway in a rat model of early brain injury in subarachnoid hemorrhage

Moderate hypothermia (MH) used as treatment for neurological diseases has a protective effect; however, its mechanism remains unclear. Neuronal autophagy is a fundamental pathological process of early brain injury in subarachnoid hemorrhage (SAH). We found that moderate activation of autophagy can reduce nerve cells damage. In this study, We found that MH can moderately increase the level of autophagy in nerve cells and improve the neurological function in rats. This type of autophagy activation is dependent on extracellular signal-regulated kinase (ERK) signaling pathways. The level of neuronal autophagy was down-regulated significantly by using U0126, an ERK signaling pathway inhibitor. In summary, these results suggest that MH can moderately activate neuronal autophagy through ERK signaling pathway, reduce nerve cell death, and produce neuroprotective effects.