Temporal patterns and distribution of pyroptosis-related molecules and effects of human mesenchymal stem cells on pyroptosis following cerebral ischemia/reperfusion in rats.

OBJECTIVES: Pyroptosis is a new type of programmed cell death that has a strong proinflammatory effect. The present study investigated the dynamic changes of pyroptosis-related molecules and the effect of mesenchymal stem cells (MSCs) on pyroptosis following cerebral ischemia/reperfusion (I/R). MATERIALS AND METHODS: The temporal pattern and cellular distribution of caspase-1, Gasdermin D and E (GSDMD and GSDME) in the peri-infarct area, and the effect of human MSCs on GSDMD, IL-1ß, IL-18, Lactate dehydrogenase (LDH) and neurological function were studied in a rat model of transient focal cerebral ischemia. RESULTS: The expression of caspase-1 mRNA increased with time, with a protein level of pro-caspase-1 comparable to its mRNA level, while the level of cleaved-caspase-1 protein peaked at 48 h following I/R. Increased levels of GSDMD mRNA and protein were also observed, with a peak level at 24 h. There were no significant changes in GSDME mRNA or protein expression after I/R. In regards to changes in the number of cells expressing GSDMD after I/R, that for neurons was more significant than those for microglia and astrocytes. The modified neurological severity score discrepancy and the expression of GSDMD showed no significant differences within 24 h following I/R between the MSC- and NS-treated groups, but MSCs treatment promoted the secretion of IL-1ß, IL-18 and LDH. CONCLUSIONS: In the early stage of cerebral infarction in rats, there were dynamic changes in pyroptosis-related molecules (caspase-1 and GSDMD), but MSCs showed no effect on the levels of GSDMD or neurological function.

Post-thrombolysis early neurological deterioration occurs with or without hemorrhagic transformation in acute cerebral infarction: risk factors, prediction model and prognosis.

Objectives: Early neurological deterioration (END) after ischemic stroke is a severe clinical event and can be caused by hemorrhagic and ischemic injury. We studied the difference between the risk factors of END occurs with or without hemorrhagic transformation after intravenous thrombolysis. Materials and methods: Consecutive cerebral infarction patients who underwent intravenous thrombolysis from 2017 to 2020 in our hospital were retrospectively recruited. END was defined as a ≥2 points increase on 24-h National Institutes of Health Stroke Scale (NIHSS) score after therapy compared with the best neurological status after thrombolysis and divided into two types based on the computed tomography (CT): symptomatic intracranial hemorrhage (ENDh) and non-hemorrhagic factors (ENDn). Potential risk factors of ENDh and ENDn were assessed by multiple logistic regression and applied to establish the prediction model. Results: A total of 195 patients were included. In multivariate analysis, the previous history of cerebral infarction (odds ratio [OR],15.19; 95% confidence interval [CI],1.43-161.17; P = 0.025), previous history of atrial fibrillation (OR,8.43; 95%CI,1.09-65.44; P = 0.043), higher baseline NIHSS score (OR,1.19; 95%CI,1.03-1.39; P = 0.022) and higher alanine transferase level (OR,1.05; 95%CI, 1.01-1.10; P = 0.016) were independently associated with ENDh. While higher systolic blood pressure (OR,1.03; 95%CI,1.01-1.05; P = 0.004), higher baseline NIHSS score (OR,1.13; 95%CI,2.86-27.43; P < 0.000) and large artery occlusion (OR,8.85, 95%CI,2.86-27.43; P < 0.000) were independent risk factors of ENDn. The prediction model showed good specificity and sensitivity in predicting the risk of ENDn. Conclusions: There are differences between the major contributors to ENDh and ENDn, while a severe stroke can increase the occurrence of both sides.

Microglial and Neuronal Cell Pyroptosis Induced by Oxygen-Glucose Deprivation/Reoxygenation Aggravates Cell Injury via Activation of the Caspase-1/GSDMD Signaling Pathway.

Pyroptosis is a new type of programmed cell death, which induces a strong pro-inflammatory reaction. However, the mechanism of pyroptosis after brain ischemia/reperfusion (I/R) and the interaction between different neural cell types are still unclear. This study comprehensively explored the mechanisms and interactions of microglial and neuronal pyroptosisin the simulated I/R environment in vitro. The BV2 (as microglial) and HT22(as neuronal) cells were treated by oxygen-glucose deprivation/reoxygenation (OGD/R). Both BV2 and HT22 cells underwent pyroptosis after OGD/R, and the pyroptosis occurred at earlier time point in HT22than that of BV2. Caspase-11 and Gasdermin E expression in BV2 and HT22 cells did not change significantly after OGD/R. Inhibition of caspase-1 or GSDMD activity, or down-regulation of GSDMD expression, alleviated pyroptosis in both BV2 and HT22 cells after OGD/R. Transwell studies further showed that OGD/R-treated HT22 or BV2 cells aggravated pyroptosis of adjacent non-OGD/R-treated cells, which could be relieved by inhibition of caspase-1 or GSDMD. These results suggested that OGD/R induces pyroptosis of microglia and neuronal cells and aggravates cell injury via activation of caspase-1/GSDMD signaling pathway. Our findings indicated that caspase-1 and GSDMD may be therapeutic targets after cerebral I/R.

Enzymatic acylation of lutein with a series of saturated fatty acid vinyl esters and the thermal stability and anti-lipid oxidation properties of the acylated derivatives.

Lutein was enzymatically acylated with saturated fatty acid vinyl esters of different lengths of carbon chain (C6 -C14 ) under the action of Candida antarctica lipase B (Novozyme 435). The acylation reaction was optimized by considering substrate molar ratio, reaction solvent, type of enzyme, and reaction time. The highest yield (88%) was obtained using the Novozyme 435 to catalyze the acylation reaction of lutein and vinyl decanoate (lutein/vinyl decanoate molar ratio of 1/10) for 16 h in methyl tert-butyl ether. Ten lutein esters were synthesized, isolated, and purified, which were characterized by Fourier-transform infrared spectroscopy, high-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy. We found that the acylation of lutein improved its antioxidant capacity in lipid system and thermal stability. Our study extended the potential application of lutein in lipophilic food, cosmetic, and pharmaceutical industries. Practical Application: Enzyme acylation of lutein improved its antioxidant capacity in lipid system and thermal stability, extended its potential application in food, cosmetic, and pharmaceutical industries. In addition, our study also provided a new perspective and cognition for the further development and utilization of lutein.

Enzymatic acylation of rutin with benzoic acid ester and lipophilic, antiradical, and antiproliferative properties of the acylated derivatives.

Rutin (3',4',5,7-tetrahydroxy-flavone-3-rutinoside) was enzymatically acylated with benzoic acid and its esters (methyl benzoate and vinyl benzoate) using Thermomyces lanuginosus lipase (Lipozyme TLIM). The acylation reaction was optimized by varying the reaction medium, reaction temperature, acyl donor, substrate molar ratio, and reaction time. The highest conversion yield (76%) was obtained in tert-amyl alcohol (60 °C, 72 hr) using vinyl benzoate (molar ratio of 1:10) as acyl donor. The acylation occurred at the 2'''-OH and 4'''-OH of the rhamnose unit and the 2''-OH position of the glucose moieties. Three novel rutin acylated derivatives (compounds 1-3) were purified and characterized by HR-MS and 1D and 2D NMR spectroscopy. We found that acylation significantly improved lipophilicity, capacity to inhibit lipid peroxidation, anticancer capacity and substantially maintained the antioxidant activity of rutin. This research provides important insights in the acylation of flavonoids with different glycosyl moieties. PRACTICAL APPLICATION: In this study, three novel rutin derivatives were successfully synthesized and the highest conversion yield (76%) was obtained by reacting the rutin and vinyl benzoate at molar ratio of 1:10 in tert-amyl alcohol for 72 hr at 60 °C. Introducing a benzoic acid substituent into rutin molecule significantly improved their lipophilicity and inhibition of lipid peroxidation in lipophilic system. Furthermore, this study demonstrated that acylation significantly improved anticancer capacity and substantially maintained the antioxidant activity.

The effects of nuclear factor-kappa B in pancreatic stellate cells on inflammation and fibrosis of chronic pancreatitis.

The activation of pancreatic stellate cells (PSCs) plays a critical role in the progression of pancreatic fibrosis. Nuclear factor-kappa B (NF-κB) is associated with chronic pancreatitis (CP). Previous evidence indicated that NF-κB in acinar cells played a double-edged role upon pancreatic injury, whereas NF-κB in inflammatory cells promoted the progression of CP. However, the effects of NF-κB in PSCs have not been studied. In the present study, using two CP models and RNAi strategy of p65 in cultured PSCs, we found that the macrophage infiltration and MCP-1 expression were increased, and the NF-κBp65 protein level was elevated. NF-κBp65 was co-expressed with PSCs. In vitro, TGF-ß1 induced overexpression of the TGF-ß receptor 1, phosphorylated TGF-ß1-activated kinase 1 (p-TAK1) and NF-κB in the PSCs. Moreover, the concentration of MCP-1 in the supernatant of activated PSCs was elevated. The migration of BMDMs was promoted by the supernatant of activated PSCs. Further knockdown of NF-κBp65 in PSCs resulted in a decline of BMDM migration, accompanied by a lower production of MCP-1. These findings indicate that TGF-ß1 can induce the activation of NF-κB pathway in PSCs by regulating p-TAK1, and the NF-κB pathway in PSCs may be a target of chronic inflammation and fibrosis.

CircRNA expression profiles and function prediction in peripheral blood mononuclear cells of patients with acute ischemic stroke.

Most circular RNAs (circRNAs) belong to a novel class of noncoding RNAs that are produced by back-splicing reactions, and they regulate physiological and pathophysiological processes in human disease. Although circRNA expression has been shown to be altered in the ischemic cerebral tissue in animal studies, the expression profile of circRNA in the patients with acute ischemic stroke (AIS) has not been investigated to date. In this investigation, high-throughput sequencing was carried out to compare the circRNA expression of peripheral blood mononuclear cells (PBMCs) from five patients with AIS and five healthy subjects. A total of 521 circRNAs were expressed differentially between the patients with AIS and healthy controls (p < .05, fold difference ≥2) including 373 upregulated circRNAs and 148 downregulated circRNAs in patients with AIS compared to controls. Thirteen candidate circRNAs were verified by quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatics analyses showed that these differentially expressed circRNAs were highly conserved, as well as eight circRNAs that were confirmed by qRT-PCR containing binding sites to multiple microRNAs. Kyoto Encyclopedia of Genes and Genomes pathway enrichment and gene ontology analyses indicated that the aberrantly expressed circRNAs participated in many pathophysiological processes of AIS, especially regarding inflammation and immunity. In conclusion, patients with AIS differentially express certain circRNAs in PBMCs, which may be diagnostic biomarkers or potential therapeutic targets.

Safety and Feasibility of Repeated Intrathecal Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells in Patients with Neurological Diseases.

Mesenchymal stromal cells (MSCs) have become the most commonly used adult stem cells in regenerative medicine. Preclinical studies have shown that MSCs-based therapy is a potential new treatment approach for neurological diseases. Intrathecal injection has unique feature which allows stem cells to directly migrate to the lesion site in patients with central nervous system (CNS) diseases. In this study, we evaluate the safety and feasibility of intrathecal allogeneic bone marrow-derived MSCs (BM-MSCs) in patients with neurological diseases. This open-label clinical study included 37 patients (14 diseases). Eligible patients underwent a baseline assessment and were intrathecally injected with allogeneic BM-MSCs (1 × 106 cells/kg, 4 consecutive treatments at 1-week intervals). After four infusions, the patients were followed up for at least 6 months. Adverse events, cerebrospinal fluid (CSF) test results, clinical symptoms, physical examination, and haematological and imaging examinations were used to assess the safety and feasibility of the treatment. Also, we performed a systematic review of the safety of all types of intrathecal stem cells and compared our result to previous studies. In our study, the highest adverse event was a slight ache at the injection site (4.11%), followed by fever (3.42%) and mild headache (2.05%). No severe adverse events were reported. After the intrathecal injections, the white blood cell (WBC) counts in the CSF increased in 30 patients and the protein concentration in the CSF exceeded the normal range in 26 patients, while other CSF indicators remained normal. Moreover, these patients had no suspected manifestations of CNS infection. Haematological and imaging examinations showed no abnormal changes after BM-MSCs infusion. Compared with previous studies, the incidence of adverse events was nearly consistent or even lower for headache, fever, nausea, and neck pain. In conclusion, repeated intrathecal allogeneic BM-MSCs are safe, feasible, and promising for the treatment of patients with neurological diseases.

Intrathecal Injection of Allogenic Bone Marrow-Derived Mesenchymal Stromal Cells in Treatment of Patients with Severe Ischemic Stroke: Study Protocol for a Randomized Controlled Observer-Blinded Trial.

Mesenchymal stromal cells (MSCs) can differentiate into multiple tissues. Preclinical studies have shown that MSC-based therapy is a potential new treatment approach for ischemic stroke. These results support the urgent need for further studies of MSC transplantation in the treatment of ischemic stroke in humans. Here, we develop a prospective, randomized, controlled, observer-blinded phase II trial to assess the clinical safety, feasibility, and therapeutic mechanisms of allogenic bone marrow-derived MSCs (BM-MSCs) by intrathecal infusion in the treatment of patients with cerebral infarction within the middle cerebral artery and with a National Institutes of Health Stroke Scale (NIHSS) score from 15 to 25. Sample size calculation has determined that a patient population of 118, with ischemic stroke between 30 and 90 days following onset, will be randomly divided into experimental (n = 59) and control (n = 59) groups. Then eligible patients will receive four intrathecal infusions of allogenic BM-MSCs (1 × 106 cells/kg body weight) once a week. All patients have detailed functional assessments and magnetic resonance imaging prior to cell infusion and at intervals up to 1 year after. The primary outcome is the score on the modified Rankin Scale at 90 days after treatment, and the second outcomes include multiple indicators of safety and feasibility. And this trial has been registered as ChiCTR-INR-16008908 (25 July 2016).

The TLR9 Antagonist iCpG-ODN at Different Dosages Inhibits Cerebral Ischemia/Reperfusion Injury in Mice.

BACKGROUND: Inflammatory responses are important mechanisms that are involved in cerebral ischemia/reperfusion(I/R) injury. Whether toll-like receptor 9(TLR9), which belongs to the innate immune system, takes part in the inflammatory responses following cerebral I/R remains unclear. METHOD: This study examined the effect of different dosages of the TLR9 antagonist inhibitory oligodeoxynucleotide (iCpG-ODN) on cerebral I/R injury by using a mouse model of transient middle cerebral artery occlusion. Neurological function, infarct size, splenocytes and the expression of TLR9 and the downstream products of the TLR9 pathways were determined after cerebral I/R for up to 72 hours. RESULTS: The Clark's focal symptom scoring showed iCpG-ODN improved neurological deficits following focal cerebral I/R. The iCpG-ODN administration significantly decreased the infarct size in a dose-dependent manner. RT-PCR showed that iCpG-ODN attenuated the I/R-induced RNA expression of TLR9. Immunoblot showed that iCpG-ODN prevented I/R-induced increases in NFκB and IRF7 levels and that it further downregulated the levels of IL-1ß, TNF-α, and INF-ß in the brain. iCpG-ODN did not alter the levels of TNF-α or INF-ß in the peripheral blood or affect stroke-induced changes in the number of splenocytes. CONCLUSION: These findings suggest that iCpG-ODN induced protection against cerebral I/R via inhibiting inflammatory responses in a dose-dependent manner and may be useful in therapy for stroke patients.

Toll-Like Receptor 3 and Interferon ß mRNA Expressions Were Increased in Peripheral Blood of Ischemic Stroke Patients with Good Outcome.

BACKGROUND: Innate immunity plays an important role in brain ischemic injury, but there are only few studies on the effects of toll-like receptors (TLRs) on cerebral infarction patients up to now. We aimed to evaluate the TLR mRNA expression of patients with different outcomes. METHODS: Eighty-six cases suffering from cerebral infarction within 14 days were assigned into the good outcome group (n = 47) and the bad outcome group (n = 39) depending on the modified Rankin Scale scores (mRS ≤2 at 90 days following stroke onset was good outcome). We measured the mRNA expression of TLRs in peripheral blood mononuclear cells of patients at 24 hours, 3 days, 4 days, 7 days, and 14 days from onset. The National Institutes of Health Stroke Scale score and infarction volume were assessed on admission and at 7-14 days, respectively. RESULTS: Only TLR3 mRNA expression of the good outcome group was higher than that of the bad outcome group at acute and subacute phases. TLR7 expressions of the good outcome group increased within 3 days following stroke onset. Moreover, the two groups had no significant differences in terms of mRNA expressions of TLR2, TLR4, TLR8, and TLR9. The expression of interferon ß of the good outcome group was higher than that of the bad outcome group, and it had a positive correlation with the expressions of TLR3 and interferon regulatory factor 3. CONCLUSIONS: TLR3 and interferon ß mRNA expressions were increased in the peripheral blood of ischemic stroke patients with good outcome, which may imply their neuroprotection.