Propionic acid ameliorates cognitive function through immunomodulatory effects on Th17 cells in perioperative neurocognitive disorders.

Background: Elderly patients undergoing surgery are prone to cognitive decline known as perioperative neurocognitive disorders (PND). Several studies have shown that the microglial activation and the decrease of short-chain fatty acids (SCFAs) in gut induced by surgery may be related to the pathogenesis of PND. The purpose of this study was to determine whether microglia and short-chain fatty acids were involved in cognitive dysfunction in aged rats. Methods: Male wild-type Wistar rats aged 11-12 months were randomly divided into control group (Ctrl: Veh group), propionic acid group (Ctrl: PA group), exploratory laparotomy group (LP: Veh group) and propionic acid + exploratory laparotomy group (LP: PA group) according to whether exploratory laparotomy (LP) or PA pretreatment for 21 days was performed. The motor ability of the rats was evaluated by open field test on postoperative day 3 (POD3), and then the cognitive function was evaluated by Y-maze test and fear conditioning test. The expression of IL-1ß, IL-6, RORγt and IL-17A mRNA in hippocampus was detected by RT-qPCR, the expression of IL-17A and IL-17RA in hippocampus was detected by Western blot, and the activation of microglia was detected by immunofluorescence. Results: The PND rat model was successfully established by laparotomy. Compared with Ctrl: Veh group, the body weight of LP: Veh group decreased, the percentage of spontaneous alternations in Y maze decreased (P < 0.001), and the percentage of freezing time in contextual fear test decreased (P < 0.001). Surgery triggers neuroinflammation, manifested as the elevated levels of the inflammatory cytokines IL-1ß (P < 0.001) and IL-6 (P < 0.001), the increased expression of the transcription factor RORγt (P = 0.0181, POD1; P = 0.0073, POD5)and major inflammatory cytokines IL-17A (P = 0.0215, POD1; P = 0.0071, POD5), and the increased average fluorescence intensity of Iba1 (P < 0.001, POD1; P < 0.001, POD5). After PA preconditioning, the recovery of rats in LP: PA group was faster than that in LP: Veh group as the body weight lost on POD1 (P = 0.0148) was close to the baseline level on POD5 (P = 0.1846), and they performed better in behavioral tests. The levels of IL-1ß (P < 0.001) and IL-6 (P = 0.0035) inflammatory factors in hippocampus decreased on POD1 and the average fluorescence intensity of Iba1 decreased (P = 0.0024, POD1; P < 0.001, POD5), representing the neuroinflammation was significantly improved. Besides, the levels of RORγt mRNA (P = 0.0231, POD1; P = 0.0251, POD5) and IL-17A mRNA (P = 0.0208, POD1; P = 0.0071, POD5) in hippocampus as well as the expression of IL-17A (P = 0.0057, POD1; P < 0.001, POD5) and IL-17RA (P = 0.0388) decreased. Conclusion: PA pretreatment results in reduced postoperative neuroinflammation and improved cognitive function, potentially attributed to the regulatory effects of PA on Th17-mediated immune responses.

Hippocampal estrogens rescued the decline of synaptic plasticity after surgery and anesthesia by inhibiting microglia overactivation.

BACKGROUND: Elderly patients experience postoperative cognitive impairment frequently; therefore, effective interventions are urgently needed. Central nervous inflammation characterized by microglia may promote the progression of POCD by reducing synaptic plasticity. Notably, clinical studies revealed that the incidence of female patients was significantly lower than that of male patients. Besides, the brain estrogens have an anti-inflammatory effect and regulate the microglia at the same times. This study aimed to determine whether suppressing microglia overactivation by hippocampal estrogens can rescue the decrease of synaptic plasticity after surgery and anesthesia. METHODS: Exploratory laparotomy was used to establish the POCD model in 15-month-old male or female C57BL/6 J mice and animal behavioral tests were performed to test hippocampal-dependent memory capacity. Western blot and immunofluorescence were used to detect the microglial activation and plasticity related protein expressions. Elisa was used to detect the content of estrogens in the hippocampus. Estrogens and estrogen receptor inhibitor were used to replenish the estrogens in the brain and inhibit the effect of estrogens. RESULTS: Surgery and anesthesia did not cause POCD in female mice (P > 0.05), while the cognitive function decreased significantly after estrogen receptor inhibitor was given(P < 0.05). Male mice experienced cognitive dysfunction after surgery and anesthesia, and their cognitive function improved after estrogens supplementation (P < 0.05). Given estrogens and estrogen receptor inhibitors at the same time, the cognitive function of male mice could not be saved (P < 0.05). By correlation analysis, there was a negative correlation between the content of hippocampal estrogens and microglia (P < 0.05). The number or degree of activation of microglia affected the synaptic plasticity, which ultimately regulated the cognitive function of mice. CONCLUSION: Hippocampal estrogens rescued the decline of synaptic plasticity after surgery and anesthesia by inhibiting microglia overactivation.

Research progress on the role and regulatory mechanism of pathogenic Th17 cells in neuroinflammation.

Neuroinflammation is a complex immune response in the central nervous system against various factors such as injury, infection and toxins which interfere with homeostasis, involving a variety of immune cells lingering in the central nervous system. Persistent neuroinflammation is a common denominator of the etiology and course of all neurological diseases, including neurodevelopmental, neurodegenerative and psychiatric disorders, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and depression. Th17 cells, known as an important subtpye of CD4 + T cells, mediate immune responses against extracellular bacteria and fungi in steady-state and maintain the defense function of the intestinal mucosal barrier. However, when the cytokine microenvironment in vivo undergoes inflammatory changes, Th17 cells can transform into a highly pro-inflammatory pathogenic phenotype, break through the blood-brain barrier and recruit more inflammatory cells to participate in neuroinflammation, ultimately leading to neurodegeneration. In this review, we summarize the differentiation regulation of pathogenic Th17 cells and their roles in neuroinflammation, which is informative for understanding the interactions between immune system and nervous system.

Laparotomy-Induced Peripheral Inflammation Activates NR2B Receptors on the Brain Mast Cells and Results in Neuroinflammation in a Vagus Nerve-Dependent Manner.

Background: The pathophysiological mechanisms underlying postoperative cognitive dysfunction (POCD) remain unclear over the years. Neuroinflammation caused by surgery has been recognized as an important element in the development of POCD. Many studies also suggest that the vagus nerve plays an important role in transmitting peripheral injury signals to the central nervous system (CNS) and the resultant neuroinflammation. Previously, we have demonstrated that brain mast cells (BMCs), as the "first responders", play a vital role in neuroinflammation and POCD. However, how the vagus nerve communicates with BMCs in POCD has not yet been clarified. Methods: In the current study, we highlighted the role of the vagus nerve as a conduction highway in surgery-induced neuroinflammation for the first time. In our model, we tested if mice underwent unilateral cervical vagotomy (VGX) had less neuroinflammation compared to the shams after laparotomy (LP) at an early stage. To further investigate the roles of mast cells and glutamate in the process, we employed KitW-sh mice and primary bone marrow-derived MCs to verify the glutamate-NR2B axis on MCs once again. Results: Our results demonstrated that there were higher levels of glutamate and BMCs activation as early as 4 h after LP. Meanwhile, vagotomy could partially block the increases and reduce neuroinflammation caused by peripheral inflammation during the acute phase. Excitingly, inhibition of NR2B receptor and knockout of mast cells can attenuateneuroinflammation induced by glutamate. Conclusion: Taken together, our findings indicate that the vagus is a high-speed pathway in the transmission of peripheral inflammation to the CNS. Activation of BMCs triggered a neuroinflammatory cascade. Inhibition of NR2B receptor on BMCs can reduce glutamate-induced BMCs activation, neuroinflammation, and memory impairment, suggesting a novel treatment strategy for POCD.

An immunochromatographic assay utilizing magnetic nanoparticles to detect major peanut allergen Ara h 1 in processed foods.

This study describes an immunomagnetic nanoparticle (IMNP)-based lateral flow assay (LFA) for detecting the major peanut allergen Ara h 1. We developed a clearly specific method in identifying peanut from ten other seeds and nuts, and a good visual limit of detection (vLOD) of 0.01 µg/mL Ara h 1 in PBS. PBS that contains 1 M NaCl and 2% Tween 20 was determined to be the optimal extraction buffer for isolating Ara h 1 from cookie, milk and chocolate with vLOD values of 0.5 µg/g, 0.5 µg/mL, and 1 µg/g, respectively. Forty two processed foods were simultaneously analyzed using this method and an AOAC-approved ELISA kit. The specificity and sensitivity of this assay were thus determined to be 100 and 95%, respectively. This new IMNP-based LFA has potential as a rapid tool for screening processed foods for Ara h 1 residues.

Hemoperfusion with HA380 in acute type A aortic dissection patients undergoing aortic arch operation (HPAO): a randomized, controlled, double-blind clinical trial.

BACKGROUND: Cardiopulmonary bypass (CPB) is an important cause of significant systemic inflammatory response syndrome (SIRS) in the surgical treatment of acute type A aortic dissection (ATAAD). In patients with arch vessel involvement, extensive surgical repairs often necessitate prolonged use of CPB and results in extensive inflammatory responses. Cytokines and chemokines released during CPB contribute to the progression of SIRS, increase perioperative complications, and negatively impact surgical outcomes. A cytokine adsorber (HA380) is expected to reduce the level of cytokines during CPB, which may decrease both intraoperative and postoperative inflammation. The purpose of this study is to investigate if HA380 is able to reduce the levels of inflammatory cytokines and decrease perioperative complications in ATAAD patients undergoing CPB and deep hypothermic circulatory arrest (DHCA). METHODS: This study is a single-center, randomized, controlled, double-blind clinical trial. The study aims to recruit 88 patients with ATAAD and aortic arch involvement who will undergo CPB and DHCA to repair the dissected aorta. Patients will be randomized equally into the CPB/DHCA only group (control group) and the CPB/DHCA + HA380 hemoperfusion group (intervention group), with 44 patients each. Patients in the control group will undergo CPB and DHCA only, while patients in the intervention group will undergo continuous hemoperfusion with HA380, in addition to CPB and DHCA. The primary outcome is a composite of major perioperative complications. The secondary outcomes include related inflammatory markers, coagulation parameters, and minor perioperative complications. To comprehensively evaluate the effect of hemoperfusion on the perioperative outcomes, we will also determine if there are differences in perioperative all-cause mortality, length of ICU stay, and total hospitalization costs. DISCUSSION: In the current trial, hemoperfusion will be applied in patients undergoing CPB and DHCA for repair of the aorta involving the aortic arch. This trial aims to test the safety and efficacy of our hemoperfusion device (HA380) in such settings. Upon completion of the trial, we will determine if HA380 is effective in reducing perioperative proinflammatory cytokine levels. Further, we will also verify if reduction in the proinflammatory cytokine levels, if present, translates to improvement in patient outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04007484 . Registered on 1 July 2019 (retrospectively registered).

Rapidly detecting major peanut allergen-Ara h2 in edible oils using a new immunomagnetic nanoparticle-based lateral flow assay.

Ara h2 is a major peanut allergen that induces rashes, vomiting, diarrhea, and anaphylactic shock. Since peanut is a major source in producing edible oils globally, Ara h2 residues can be present in various edible oils. In this work, an immunomagnetic nanoparticle-based lateral flow assay for identifying Ara h2 in edible oils is developed. This assay exhibits high sensitivity with a visual detection limit of 0.1 mg/kg Ara h2 in oil, and favorable specificity in differentiating peanut from seeds and nuts. The calculated CV values of intra- and inter-assay were 6.73-10.21% and 4.75-8.57%, respectively, indicating high reproducibility. In an analysis of 26 oil products, Ara h2 was detected in two peanut oils as 0.122 ±â€¯0.026 mg/kg and 0.247 ±â€¯0.027 mg/kg. The entire method takes 5 h, including a 3.5-h sample preparation. Hence, this method has the potential to be an effective way to screen edible oils for Ara h2.

Intervention effects of nedaplatin and cisplatin on proliferation and apoptosis of human tumour cells in vitro.

OBJECTIVE: To study synergistic effects of nedaplatin and cisplatin on three human carcinoma cell lines (esophageal carcinoma cell line Eca-109, ovarian carcinoma Skov-3 and cervical carcinoma Hela). METHODS: Inhibition effects were evaluated by MTT assay and cell apoptosis was detected by flow cytometry. In addition, changes of Ki-67, Bax and Bcl-2 at mRNA and protein levels were quantified by RT-PCR and Western blotting. RESULTS: Growth inhibition in each cell lines was dose-dependent after exposure to nedaplatin or cisplatin alone. The interaction of the two drugs was synergistic at higher concentrations according to the median-effect principle. The inhibition rates with nedaplatin, cisplatin and combined treatment were 41.9±4.1%, 47.4±2.9%, 52.5±0.9%(Eca-109), 39.0±1.26%, 45.0±1.45% , 56.2±1.44% (Skov-3) and 44.8±2.11%, 46.9±0.99%, 56.6±1.83% (Hela) respectively, with increase in apoptosis. Compared with the nedaplatin or cisplatin alone treatment group, the combinative treatment group's Ki-67 and bcl-2 mRNA (protein) expression was decreased while that of Bax mRNA (protein) was increased. CONCLUSION: Compared to the effects of nedaplatin or cisplatin alone at high concentrations, combination of nedaplatin and cisplatin at low concentrations proved to be much more effective for inhibition of proliferation and the induction of apoptosis in the Eca-109, Skov-3 and Hela cell lines.

[Study protocol for a self-controlled case study to evaluate the safety and standardization for external application of Chinese medicine Jiuyi Powder].

BACKGROUND: As the main medicinal powder for drawing out pus and removing necrotic tissue in external therapies of traditional Chinese surgery, Sheng Powder has made great contributions to the treatment of inflammatory wounds and has the unique bactericidal and decay-discharging function that can not be replaced by antibiotics. However, Sheng Powder has toxicity because it contains mercury. So far, there is no clinical research on the standards of dose and usage of Sheng Powder and there is a lack of objective and quantitative criteria for operating standards and monitoring of toxicity and side effects. Therefore, the authors choose Jiuyi Powder, one of the most commonly used Sheng Powder, to evaluate the safety of its external use, and form a standardization program for clinical implementation. METHODS AND DESIGN: This study is a nonrandomized, nonblinded, self-controlled case study. There will be two key stages in the study. In stage one, 10 patients with plasma cell mastitis will be enrolled. The patients will receive continuous external application of Jiuyi Powder with a fixed dose (160 mg/d). Blood mercury and urine mercury levels will be dynamically tested at different time intervals, and the observation of pharmacokinetic parameters will be conducted after Jiuyi Powder has been absorbed by the surface of the wound. In stage two, 30 patients with each of the four conditions including postoperative wounds of head or facial surgeries, plasma cell mastitis, anal fistula and chronic absorption ulcer of the shank will be enrolled, respectively. According to the dose of 1.5 mg/cm(2), Jiuyi Powder will be externally applied to the wound surface for 14 d. On the basis of the first-phase study, the test time will be chosen and the toxicity outcome will be detected to evaluate the safety of external application of Jiuyi Powder and to establish recommendations for standardized clinical use. DISCUSSION: The purpose of this study is to evaluate the safety of the external application of Jiuyi Powder through a two-stage study. The pharmacokinetic parameters of external application of Jiuyi Powder at the clinical dose range, the changes in blood and urinary mercury levels and related safety indexes will be observed on different wounds located in different positions externally. The evaluation of whether Jiuyi Powder could be a routine medication for drawing out pus and removing necrotic tissue in inflammatory and refractory wounds will be stated. TRIAL REGISTRATION NUMBER: ChiCTR-TNC-11001366.

Lobaplatin suppresses proliferation and induces apoptosis in the human colorectal carcinoma cell Line LOVO in vitro.

Lobaplatin, as the third-generation platinum antineoplastic agent, showed promising antineoplastic effects in variety of preclinical test tumor models. We investigated the inhibition effect of lobaplatin on the colorectal carcinoma cell line LOVO in vitro, and explored its mechanism of action. The MTT assay was used to determine the inhibitory effect and inhibition ratio of lobaplatin on LOVO at various lobaplatin concentrations (500 µM, 1000 µM, 2000 µM). Apoptosis was detected by terminal deoxynucleotide transferase-mediated dUTP nickend labelling (TUNEL). The cell cycle and apoptotic rate were analyzed by flow cytometry (FCM) and the expression of caspase-3,8,9 in cells was detected by chromometry. The results of MTT assay showed that proliferation of LOVO cells was inhibited by lobaplatin in a concentration-dependent manner. Apoptosis was detected in LOVO cells by TUNEL. The FCM assay indicated that lobaplatin altered the cell cycle and induced apoptosis of the LOVO cells when treated for 24h, the percentages of cells in the S phase transition were increased, whereas the percentages of cells in the G(2) transition were decreased. The expressions of caspase-389 is higher than the control group after LOVO cells were treated by lobaplatin. Lobaplatin can inhibit the proliferation of colorectal carcinoma cell line LOVO by inducing apoptosis in vitro. The mechanism may be related to the "S" cycle arrest in cell cycle distribution and the up-regulated expression of caspase-8 and caspase-9 which up-regulated the expression of caspase-3.