Hydroxysafflor Yellow A Inhibits Pyroptosis and Protecting HUVECs from OGD/R via NLRP3/Caspase-1/GSDMD Pathway.

OBJECTIVE: To observe the protective effect and mechanism of hydroxyl safflower yellow A (HSYA) from myocardial ischemia-reperfusion injury on human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were treated with oxygen-glucose deprivation reperfusion (OGD/R) to simulate the ischemia reperfusion model, and cell counting kit-8 was used to detect the protective effect of different concentrations (1.25-160 µ mol/L) of HSYA on HUVECs after OGD/R. HSYA 80 µ mol/L was used for follow-up experiments. The contents of inflammatory cytokines interleukin (IL)-18, IL-1 ß, monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor α (TNF-α) and IL-6 before and after administration were measured by enzyme-linked immunosorbent assay. The protein expressions of toll-like receptor, NOD-like receptor containing pyrin domain 3 (NLRP3), gasdermin D (GSDMD) and GSDMD-N-terminal domain (GSDMD-N) before and after administration were detected by Western blot. NLRP3 inflammasome inhibitor cytokine release inhibitory drug 3 sodium salt (CRID3 sodium salt, also known as MCC950) and agonist were added, and the changes of NLRP3, cysteine-aspartic acid protease 1 (Caspase-1), GSDMD and GSDMD-N protein expressions were detected by Western blot. RESULTS: HSYA inhibited OGD/R-induced inflammation and significantly decreased the contents of inflammatory cytokines IL-18, IL-1 ß, MCP-1, TNF-α and IL-6 (P<0.01 or P<0.05). At the same time, by inhibiting NLRP3/Caspase-1/GSDMD pathway, HSYA can reduce the occurrence of pyroptosis after OGD/R and reduce the expression of NLRP3, Caspase-1, GSDMD and GSDMD-N proteins (P<0.01). CONCLUSIONS: The protective effect of HSYA on HUVECs after OGD/R is related to down-regulating the expression of NLRP3 inflammasome and inhibiting pyroptosis.

Panax notoginseng saponins stimulates the differentiation and neurite development of C17.2 neural stem cells against OGD/R injuries via mTOR signaling.

Ischemic stroke remains a major disease worldwide, and most stroke patients often suffer from serious sequelae. Endogenous neurogenesis matters in the repair and regeneration of impaired neural cells after stroke. We have previously reported in vivo that PNS could strengthen the proliferation and differentiation of neural stem cells (NSCs), modulate synaptic plasticity and protect against ischemic brain injuries in cerebral ischemia rats, which could be attributed to mTOR signaling activation. Next, to obtain further insights into the function mechanism of PNS, we evaluated the direct influence of PNS on the survival, differentiation and synaptic development of C17.2 NSCs in vitro. The oxygen glucose deprivation/reperfusion (OGD/R) model was established to mimic ischemic brain injuries. We found that after OGD/R injuries, PNS improved the survival of C17.2 cells. Moreover, PNS enhanced the differentiation of C17.2 cells into neurons and astrocytes, and further promoted synaptic plasticity by significantly increasing the expressions of synapse-related proteins BDNF, SYP and PSD95. Meanwhile, PNS markedly activated the Akt/mTOR/p70S6K pathway. Notably, the mTOR inhibitor rapamycin pretreatment could reverse these desirable results. In conclusion, PNS possessed neural differentiation-inducing properties in mouse C17.2 NSCs after OGD/R injuries, and Akt/mTOR/p70S6K signaling pathway was proved to be involved in the differentiation and synaptic development of C17.2 cells induced by PNS treatment under the in vitro ischemic condition. Our findings offer new insights into the mechanisms that PNS regulate neural plasticity and repair triggered by NSCs, and highlight the potential of mTOR signaling as a therapeutic target for neural restoration after ischemic stroke.

[Baicalin improves inflammatory response of human microglia by regulating cAMP-PKA-NF-κB/CREB pathway].

This study aims to investigate the effects of baicalein(BAI) on lipopolysaccharide(LPS)-induced human microglial clone 3(HMC3) cells, with a focus on suppressing inflammatory responses and elucidating the potential mechanism underlying the therapeutic effects of BAI on ischemic stroke via modulating the cAMP-PKA-NF-κB/CREB pathway. The findings have significant implications for the application of traditional Chinese medicine in treating cerebral ischemic diseases. First, the safe dosage of BAI was screened, and then an inflammation model was established with HMC3 cells by induction with LPS for 24 h. The cells were assigned into a control group, a model group, and high-, medium-, and low-dose(5, 2.5, and 1.25 µmol·L~(-1), respectively) BAI groups. The levels of superoxide dismutase(SOD) and malondialdehyde(MDA) in cell extracts, as well as the levels of interleukin-1ß(IL-1ß), IL-6, tumor necrosis factor-α(TNF-α), and cyclic adenosine monophosphate(cAMP) in the cell supernatant, were measured. Western blot was performed to determine the expression of protein kinase A(PKA), phosphorylated cAMP-response element binding protein(p-CREB), and nuclear factor-kappa B p65(NF-κB p65). Hoechst 33342/PI staining was employed to assess cell apoptosis. High and low doses of BAI were used for treatment in the research on the mechanism. The results revealed that BAI at the concentrations of 10 µmol·L~(-1) and below had no impact on normally cultured HMC3 cells. LPS induction at 200 ng·mL~(-1) for 24 h reduced the SOD activity and increased the MDA content in HMC3 cells. However, 5, 2.5, and 1.25 µmol·L~(-1) BAI significantly increased the SOD activity and 5 µmol·L~(-1) BAI significantly decreased the MDA content. In addition, BAI ameliorated the M1 polarization of HMC3 cells induced by LPS, as indicated by cellular morphology. The results of ELISA demonstrated that BAI significantly lowered the levels of TNF-α, IL-1ß, IL-6, and cAMP in the cell supernatant. Western blot revealed that BAI up-regulated the protein levels of PKA and p-CREB while down-regulating the expression of NF-κB p65. Hoechst 33342/PI staining results indicated that BAI mitigated the apoptosis of HMC3 cells. Overall, the results indicated that BAI had protective effects on the HMC3 cells induced by LPS, and could inhi-bit inflammatory response and improve cell apoptosis, which might be related to the regulation of the cAMP-PKA-NF-κB/CREB pathway.

Bioactive peptides for anticancer therapies.

Cancer is a serious concern in public health worldwide. Numerous modalities including surgery, radiotherapy, and chemotherapy, have been used for cancer therapies in clinic. Despite progress in anticancer therapies, the usage of these methods for cancer treatment is often related to deleterious side effects and multidrug resistance of conventional anticancer drugs, which have prompted the development of novel therapeutic methods. Anticancer peptides (ACPs), derived from naturally occurring and modified peptides, have received great attention in these years and emerge as novel therapeutic and diagnostic candidates for cancer therapies, because of several advantages over the current treatment modalities. In this review, the classification and properties of ACPs, the mode of action and mechanism of membrane disruption, as well as the natural sources of bioactive peptides with anticancer activities were summarised. Because of their high efficacy for inducing cancer cell death, certain ACPs have been developed to work as drugs and vaccines, evaluated in varied phases of clinical trials. We expect that this summary could facilitate the understanding and design of ACPs with increased specificity and toxicity towards malignant cells and with reduced side effects to normal cells.

Molecular co-assembly of multicomponent peptides for the generation of nanomaterials with improved peroxidase activities.

Molecular self-assembly of peptides provides an effective approach for the fabrication of biomimetic enzymes in recent years. However, due to sophisticated architectures of native peroxidases, precise mimicking of the structure of hemin pockets within peroxidases with a single component of peptide is a great challenge. Herein, we decided to explore the potential of multicomponent peptide assembly to prepare artificial peroxidases with biomimetic hemin pockets. Hydrophobic peptides (e.g., KH, QH, NH, NHNH and NHNHNH) provide a supramolecular scaffold to form an appropriate hydrophobic binding pocket, and a proximal histidine ligand to bind hemin through the coordination between imidazole and hemin iron. A peptide with hydrophilic residues (e.g., NapFFHEKRH) was incorporated to supply distal histidine residues and hydrophilic amino acids in the distal pocket to promote H2O2 binding and stabilize a high oxidation state. Due to the synergistic molecular interactions, the components of NH, NapFFHEKRH and hemin could self-assemble into nanostructures with biomimetic microenvironments for increased substrate binding and catalytic rates of TMB oxidation, compared to the catalytic system of NHhemin without NapFFHEKRH. This work illustrates an approach for fabricating artificial peroxidases with biomimetic structural features and improved catalytic activities from co-assembly of multicomponent peptides.

Correlation and predictive value of platelet biological indicators and recurrence of large-artery atherosclerosis type of ischemic stroke.

Large-artery atherosclerosis type of ischemic stroke happens when a blood clot forms in a major artery that carries blood to the brain. This causes a blockage and a decrease in blood flow to the brain tissue making up approximately 15-20% of all cases. This type of stroke is more prevalent in older adults and those with risk factors such as high blood pressure, high cholesterol, diabetes, smoking, and a family history of stroke. To investigate the correlation and predictive value of platelet-related biological indicators with recurrence of large-artery atherosclerosis type of ischemic stroke (LAA-IS)2. The patients were divided into a relapse group (R, n = 40) and non-relapse group (NR, n = 45). Platelet-related biological indicators were collected from both groups to analyze their correlation with neurological impairment score (NIHSS score). Risk factors were analyzed using binary logistic regression and a survival curve (ROC) was drawn to evaluate the predictive effect of clinical platelet-related biological indicators on LAA-IS recurrence. This study confirmed that PAg-ADP, PAg-COL, and FIB are closely related to the formation of LAA-IS due to carotid atherosclerosis, and the combined PAg-ADP, PAg-COL, and FIB index levels are the most promising for assessing the prognostic development of recurrence in patients with LAA-IS. Combined monitoring of platelet aggregation rate and FIB index is of important evaluation value in judging the recurrence prognosis of LAA-IS patients.

Association of genetic variants of CircCHST15 with oral squamous cell carcinoma in the Chinese Han population.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most common cancer in the oral cavity. The relationship between the genetic susceptibility of circCHST15 and OSCC remains unclear. METHODS: Genetic variants of circCHST15 were screened using a genotyping analysis from 1044 patients with OSCC and 3199 healthy participants. The circCHST15 expression was detected in 32 pairs of OSCC tissues. The circular RNA quantitative trait locus analysis and the reporter gene assay were performed for verification. RESULTS: The circCHST15 expression was upregulated in OSCC (Wilcoxon p < 1e-3). The genotyping analysis screened out 61 loci in circCHST15 associated with the risk of OSCC. After adjustment and annotation, rs28707473 (A > C, odds ratio = 1.21, 95% CI: 1.076-1.361, p = 1.453e-3) was selected. This genetic variation could elevate the circCHST15 expression level possibly by altering the structure of circular RNAs and affecting transcription factor binding. CONCLUSIONS: The results of this study suggested that genetic variants of circCHST15 may contribute to OSCC susceptibility.

Highly Sensitive Gas-Sensing Films for Volatile Organic Acids from Imidazolium-Based Poly(ionic liquid)s.

Imidazolium-based poly(ionic liquid)s were synthesized and used as sensing film for the adsorption of volatile organic compounds. Based on a quartz crystal microbalance system, the sensing properties of the imidazolium-based poly(ionic liquid)s on volatile organic compounds was assessed according to the position of imidazolium cation in the polymer chain (the main-chain or side-chain type) and the varied counterions. The results indicated that the imidazolium-based poly(ionic liquid)s films have much higher adsorption capability on volatile organic acids than other volatile organic compounds, which is due to the strong affinity between imidazolium group and the carboxyl group. The position of imidazolium cation in the polymer chain and counterions of the imidazolium-based poly(ionic liquid)s was found to be able to influence the selectivity and sensitivity of volatile organic acids. The main-chain imidazolium-based poly(ionic liquid)s were shown strengthen the adsorption of propionic acid vapor, while the counter ion of dicyanamide showed the highest selectivity on volatile organic acids. Based on the quartz crystal microbalance sensing system, the imidazoliumbased poly(ionic liquid)s film was shown capable of detecting volatile organic acids with a theoretical detection limit of about 3.1 ppb and a quick recovery time less than 40 seconds. The sensing performance is also stable for repeated usage and after long-time storage.

Sailuotong Capsule Prevents the Cerebral Ischaemia-Induced Neuroinflammation and Impairment of Recognition Memory through Inhibition of LCN2 Expression.

BACKGROUND: Astrogliosis can result in astrocytes with hypertrophic morphology after injury, indicated by extended processes and swollen cell bodies. Lipocalin-2 (LCN2), a secreted glycoprotein belonging to the lipocalin superfamily, has been reported to play a detrimental role in ischaemic brains and neurodegenerative diseases. Sailuotong (SLT) capsule is a standardized three-herb preparation composed of ginseng, ginkgo, and saffron for the treatment of vascular dementia. Although recent clinical trials have demonstrated the beneficial effect of SLT on vascular dementia, its potential cellular mechanism has not been fully explored. METHODS: Male adult Sprague-Dawley (SD) rats were subjected to microsphere-embolized cerebral ischaemia. Immunostaining and Western blotting were performed to assess astrocytic reaction. Human astrocytes exposed to oxygen-glucose deprivation (OGD) were used to elucidate the effects of SLT-induced inflammation and astrocytic reaction. RESULTS: A memory recovery effect was found to be associated with the cerebral ischaemia-induced expression of inflammatory proteins and the suppression of LCN2 expression in the brain. Additionally, SLT reduced the astrocytic reaction, LCN2 expression, and the phosphorylation of STAT3 and JAK2. For in vitro experiments, OGD-induced expression of inflammation and LCN2 was also decreased in human astrocyte by the SLT treatment. Moreover, LCN2 overexpression significantly enhanced the above effects. SLT downregulated these effects that were enhanced by LCN2 overexpression. CONCLUSIONS: SLT mediates neuroinflammation, thereby protecting against ischaemic brain injury by inhibiting astrogliosis and suppressing neuroinflammation via the LCN2-JAK2/STAT3 pathway, providing a new idea for the treatment strategy of ischaemic stroke.

Ginkgo biloba Extract Inhibits Astrocytic Lipocalin-2 Expression and Alleviates Neuroinflammatory Injury via the JAK2/STAT3 Pathway After Ischemic Brain Stroke.

Background: Astrogliosis has the potential to lead to harmful effects, namely, neuroinflammation, and to interfere with synapse sprouting. Previous studies have suggested that Lipocalin-2 (LCN2) acts as a key target in regulating the reaction of astrocytes. However, the underlying molecular mechanism is not fully elucidated. In the present study, we examined the neuroprotective and anti-inflammatory effects of Ginkgo biloba extract (EGB), a well-known extract with potential immunoregulatory properties in the nervous system. Methods: Triphenyltetrazolium chloride staining, hematoxylin-eosin staining, electron microscopy, and neurological assessments were performed in a microsphere-embolized rat model. Human astrocytes exposed to oxygen glucose deprivation (OGD) were used for in vitro experiments. Inflammatory cytokines, multi-labeling immunofluorescence, and Western blotting were used to investigate the molecular mechanisms underlying the EGB-mediated anti-inflammatory effects in vivo and in vitro. Results: EGB markedly attenuated cerebral infarction and neuronal apoptosis, reduced the inflammatory cytokine level, and alleviated neurological deficiencies in cerebral ischemic rats. After surgery, EGB significantly inhibited astrocyte activation, reduced the phosphorylation of STAT3 and JAK2 and decreased LCN2 expression. In vitro, EGB blocked OGD-induced STAT3 activation and the generation of pro-inflammatory cytokines in human astrocytes, and these effects were significantly enhanced by LCN2 overexpression. EGB downregulated these effects enhanced by LCN2 overexpression. Conclusion: EGB is demonstrated to mediate neuroinflammation, which protects against ischemic brain injury by inhibiting astrogliosis and suppresses neuroinflammation via the LCN2-JAK2/STAT3 pathway, providing insight into a promising therapeutic strategy for ischemic stroke.