CircAKT3 alleviates postoperative cognitive dysfunction by stabilizing the feedback cycle of miR-106a-5p/HDAC4/MEF2C axis in hippocampi of aged mice.

Circular RNAs (circRNAs) have garnered significant attention in the field of neurodegenerative diseases including Alzheimer's diseases due to their covalently closed loop structure. However, the involvement of circRNAs in postoperative cognitive dysfunction (POCD) is still largely unexplored. To identify the genes differentially expressed between non-POCD (NPOCD) and POCD mice, we conducted the whole transcriptome sequencing initially in this study. According to the expression profiles, we observed that circAKT3 was associated with hippocampal neuronal apoptosis in POCD mice. Moreover, we found that circAKT3 overexpression reduced apoptosis of hippocampal neurons and alleviated POCD. Subsequently, through bioinformatics analysis, our data showed that circAKT3 overexpression in vitro and in vivo elevated the abundance of miR-106a-5p significantly, resulting in a decrease of HDAC4 protein and an increase of MEF2C protein. Additionally, this effect of circAKT3 was blocked by miR-106a-5p inhibitor. Interestingly, MEF2C could activate the transcription of miR-106a-5p promoter and form a positive feedback loop. Therefore, our findings revealed more potential modulation ways between circRNA-miRNA and miRNA-mRNA, providing different directions and targets for preclinical studies of POCD.

Postoperative short-term mortality between insulin-treated and non-insulin-treated patients with diabetes after non-cardiac surgery: a systematic review and meta-analysis.

Background: Diabetes mellitus is an independent risk factor for postoperative complications. It has been reported that insulin-treated diabetes is associated with increased postoperative mortality compared to non-insulin-treated diabetes after cardiac surgery; however, it is unclear whether this finding is applicable to non-cardiac surgery. Objective: We aimed to assess the effects of insulin-treated and non-insulin-treated diabetes on short-term mortality after non-cardiac surgery. Methods: Our study was a systematic review and meta-analysis of observational studies. PubMed, CENTRAL, EMBASE, and ISI Web of Science databases were searched from inception to February 22, 2021. Cohort or case-control studies that provided information on postoperative short-term mortality in insulin-treated diabetic and non-insulin-treated diabetic patients were included. We pooled the data with a random-effects model. The Grading of Recommendations, Assessment, Development, and Evaluation system was used to rate the quality of evidence. Results: Twenty-two cohort studies involving 208,214 participants were included. Our study suggested that insulin-treated diabetic patients was associated with a higher risk of 30-day mortality than non-insulin-treated diabetic patients [19 studies with 197,704 patients, risk ratio (RR) 1.305; 95% confidence interval (CI), 1.127 to 1.511; p < 0.001]. The studies were rated as very low quality. The new pooled result only slightly changed after seven simulated missing studies were added using the trim-and-fill method (RR, 1.260; 95% CI, 1.076-1.476; p = 0.004). Our results also showed no significant difference between insulin-treated diabetes and non-insulin-treated diabetes regarding in-hospital mortality (two studies with 9,032 patients, RR, 0.970; 95% CI, 0.584-1.611; p = 0.905). Conclusion: Very-low-quality evidence suggests that insulin-treated diabetes was associated with increased 30-day mortality after non-cardiac surgery. However, this finding is non-definitive because of the influence of confounding factors. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021246752, identifier: CRD42021246752.

Contribution of preoperative gut microbiota in postoperative neurocognitive dysfunction in elderly patients undergoing orthopedic surgery.

Objective: To investigate the role of gut microbiota and metabolites in POCD in elderly orthopedic patients, and screen the preoperative diagnostic indicators of gut microbiota in elderly POCD. Method: 40 elderly patients undergoing orthopedic surgery were enrolled and divided into Control group and POCD group following neuropsychological assessments. Gut microbiota was determined by 16S rRNA MiSeq sequencing, and metabolomics of GC-MS and LC-MS was used to screen the differential metabolites. We then analyzed the pathways enriched by metabolites. Result: There was no difference in alpha or beta diversity between Control group and POCD group. There were significant differences in 39 ASV and 20 genera bacterium in the relative abundance. Significant diagnostic efficiency analyzed by the ROC curves were found in 6 genera bacterium. Differential metabolites in the two groups including acetic acid, arachidic acid, pyrophosphate etc. were screened out and enriched to certain metabolic pathways which impacted the cognition function profoundly. Conclusion: Gut microbiota disorders exist preoperatively in the elderly POCD patients, by which there could be a chance to predict the susceptible population. Clinical Trial Registration: [http://www.chictr.org.cn/edit.aspx?pid=133843&htm=4], identifier [ChiCTR2100051162].

CCNI2 plays a promoting role in the progression of colorectal cancer.

Colorectal cancer (CRC) is one of the most common malignancies and most of the patients diagnosed with advanced CRC have unsatisfactory treatment effect and poor prognosis. The purpose of this study was to investigate the effect of CCNI2 on the development of CRC. In this sutdy, immunohistochemical staining was used to detect CCNI2 expression levels in clinical samples, meanwhile, the Kaplan-Meier survival analysis was conducted. Celigo cell counting assay was used for screening shCCNI2s. QPCR and WB were performed to verify knockdown efficiency of CCNI2. Cell proliferation, colony formation, cell cycle, apoptosis, and mechanism investigation of CCNI2 knockdown were investigated by MTT assay, colony formation assay, fluorescence-activated cell sorting, and human apoptosis antibody array, respectively. Otherwise, the mouse model of CCNI2 knockdown was also constructed. The results of immunohistochemical staining and qPCR indicated that CCNI2 had a high expression level in the CRC tissues and cell lines. Kaplan-Meier survival analysis manifested that the high expression of CCNI2 suggested poor prognosis. The expression of CCNI2 was significantly reduced by CCNI2-siRNAs, and the downregulated expression level of CCNI2 inhibited CRC cell proliferation and colony formation, arrested cell cycle in G2 phase, as well as promoted cell apoptosis. The various indexes of solid tumor in mice models indicated that CCNI2 knockdown could suppress the growth of CRC tumor. Based on the comprehensive analysis of the above results, CCNI2 was contributed to the progression of CRC and could serve as a prognostic marker for CRC.

Vicarious traumatization in the general public, members, and non-members of medical teams aiding in COVID-19 control.

Since December 2019, more than 79,000 people have been diagnosed with infection of the Corona Virus Disease 2019 (COVID-19). A large number of medical staff was sent to Wuhan city and Hubei province to aid COVID-19 control. Psychological stress, especially vicarious traumatization caused by the COVID-19 pandemic, should not be ignored. To address this concern, the study employed a total of 214 general public and 526 nurses (i.e., 234 front-line nurses and 292 non-front-line nurses) to evaluate vicarious traumatization scores via a mobile app-based questionnaire. Front-line nurses are engaged in the process of providing care for patients with COVID-19. The results showed that the vicarious traumatization scores for front-line nurses including scores for physiological and psychological responses, were significantly lower than those of non-front-line nurses (P < 0.001). Interestingly, the vicarious traumatization scores of the general public were significantly higher than those of the front-line nurses (P < 0.001); however, no statistical difference was observed compared to the scores of non-front-line nurses (P > 0.05). Therefore, increased attention should be paid to the psychological problems of the medical staff, especially non-front-line nurses, and general public under the situation of the spread and control of COVID-19. Early strategies that aim to prevent and treat vicarious traumatization in medical staff and general public are extremely necessary.

Key role of gut microbiota in anhedonia-like phenotype in rodents with neuropathic pain.

Patients with chronic neuropathic pain frequently suffer from symptoms of anhedonia, which is a core symptom of depression. Accumulating studies suggest that gut microbiota may play a role in depression via gut-microbiota-brain axis. However, it is unknown whether gut microbiota plays a role in neuropathic pain-associated anhedonia. Here, we used a rat model of spared nerve injury (SNI). Hierarchical cluster analysis of sucrose preference test (SPT) results was used to classify the SNI rats with or without anhedonia-like phenotype. The 16S ribosomal RNA sequencing analysis showed abnormal composition of gut microbiota in the anhedonia susceptible compared to sham-operated rats and resilient rats. Furthermore, antibiotics-treated mice showed pain as well as depression-like and anhedonia-like phenotypes, suggesting a role of gut microbiota in these abnormal behaviors. Transplantation of fecal microbiota from anhedonia susceptible rats into antibiotics-treated pseudo-germ-free mice significantly exaggerated pain and depression-like phenotypes, including anhedonia. In contrast, transplantation of fecal microbiota from resilient rats into antibiotics-treated pseudo-germ-free mice significantly improved pain and depression-like phenotypes, including anhedonia. In conclusion, this study suggests that abnormal composition of gut microbiota may contribute to anhedonia susceptibility post SNI surgery, and that gut microbiota also plays a role in the pain as well as depression-like phenotypes. Interestingly, fecal microbiota transplantation from SNI rats with or without anhedonia can alter pain, depression-like and anhedonia-like phenotypes in the pseudo-germ-free mice. Therefore, it is likely that gut microbiota plays a key role in the pain as well as depression-like phenotypes including anhedonia in rodents with neuropathic pain.

Abnormal composition of gut microbiota contributes to delirium-like behaviors after abdominal surgery in mice.

AIMS: Anesthesia and surgery can cause delirium-like symptoms postoperatively. Increasing evidence suggests that gut microbiota is a physiological regulator of the brain. Herein, we investigated whether gut microbiota plays a role in postoperative delirium (POD). METHODS: Mice were separated into non-POD and POD phenotypes after abdominal surgery by applying hierarchical clustering analysis to behavioral tests. Fecal samples were collected, and 16S ribosomal RNA gene sequencing was performed to detect differences in gut microbiota composition among sham, non-POD, and POD mice. Fecal bacteria from non-POD and POD mice were transplanted into antibiotics-induced pseudo-germ-free mice to investigate the effects on behaviors. RESULTS: α-diversity and ß-diversity indicated differences in gut microbiota composition between the non-POD and POD mice. At the phylum level, the non-POD mice had significantly higher levels of Tenericutes, which were not detected in the POD mice. At the class level, levels of Gammaproteobacteria were higher in the POD mice, whereas the non-POD mice had significantly higher levels of Mollicutes, which were not detected in the POD mice. A total of 20 gut bacteria differed significantly between the POD and non-POD mice. Interestingly, the pseudo-germ-free mice showed abnormal behaviors prior to transplant. The pseudo-germ-free mice that received fecal bacteria transplants from non-POD mice but not from POD mice showed improvements in behaviors. CONCLUSIONS: Abnormal gut microbiota composition after abdominal surgery may contribute to the development of POD. A therapeutic strategy that targets gut microbiota could provide a novel alterative for POD treatment.

Role of Actinobacteria and Coriobacteriia in the antidepressant effects of ketamine in an inflammation model of depression.

Ketamine, an N-methyl-d-aspartic acid receptor (NMDAR) antagonist, elicits rapid-acting and sustained antidepressant effects in treatment-resistant depressed patients. Accumulating evidence suggests that gut microbiota via the gut-brain axis play a role in the pathogenesis of depression, thereby contributing to the antidepressant actions of certain compounds. Here we investigated the role of gut microbiota in the antidepressant effects of ketamine in lipopolysaccharide (LPS)-induced inflammation model of depression. Ketamine (10 mg/kg) significantly attenuated the increased immobility time in forced swimming test (FST), which was associated with the improvements in α-diversity, consisting of Shannon, Simpson and Chao 1 indices. In addition to α-diversity, ß-diversity, such as principal coordinates analysis (PCoA), and linear discriminant analysis (LDA) coupled with effect size measurements (LEfSe), showed a differential profile after ketamine treatment. Furthermore, a total of 30 bacteria were significantly altered in the LPS + saline treated mice and LPS + ketamine treated mice. Interestingly, two bacteria, including the phylum Actinobacteria and the class Coriobacteriia were significantly correlated with the immobility time of FST. Importantly, the receiver operating characteristic (ROC) curves demonstrated that the phylum Actinobacteria and the class Coriobacteriia were potential biomarker for the antidepressant effects of ketamine in an inflammation model. These findings suggest that antidepressant effects of ketamine might be related to the regulation of abnormal composition of gut microbiota, and that the phylum Actinobacteria and the class Coriobacteriia might be potential biomarkers for ketamine's antidepressant efficacy.

Critical role of matrix metallopeptidase 9 in postoperative cognitive dysfunction and age-dependent cognitive decline.

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a significant clinical syndrome. Neuroinflammation is an important pathological process for POCD. However, it is not clear how systemic inflammation induced by surgery on peripheral tissues or organs is transmitted into the brain. We determined whether matrix metallopeptidase 9 (MMP9), a protein that can increase blood-brain barrier permeability, is critical in this transmission. The role of MMP9 in age-dependent cognitive decline was also determined. METHODS: Two-month old male C57BL/6J wild-type mice and MMP9-/- mice were randomly assigned to control or surgery groups. The surgery was right carotid artery exposure under isoflurane anesthesia. Cognitive function was tested from one week after the surgery by Barnes maze and fear conditioning. Cognitive function of 2-month old C57BL/6J mice was compared with that of 18-month old mice. RESULTS: Surgery increased the expression of interleukin 1ß, interleukin 6 and ionized calcium binding adapter molecule 1, inflammation indicators, in the brain of the wild-type mice. Blood-brain barrier permeability was increased by surgery. Surgery also impaired the learning and memory of these mice. These surgical effects were absent in the MMP9-/- mice. Eighteen-month old wild-type mice had poorer performance in Barnes maze and fear conditioning tests and lower MMP9 protein expression and activity than did the 2-month old mice. CONCLUSION: MMP9 is critical for transmission of systemic inflammation into the brain for POCD. MMP9 may also play a role in age-dependent cognitive decline.

Glutamate transporter type 3 participates in maintaining morphine-induced conditioned place preference.

Glutamate transporters (EAAT) have been implicated in the drug addiction behavior. We determined whether EAAT type 3 (EAAT3) played a role in morphine addiction. Six- to eight-week-old EAAT3 knockout (EAAT3-/-) mice and their wild-type littermates received 3 intraperitoneal injections of 10mg/kg morphine, each on an alternative day, to induce conditioned place preference (CPP). Two days after the place preference returned to baseline, mice received 2.5mg/kg morphine to induce reinstatement. Some mice received intraperitoneal injection of 4mg/kg riluzole, an EAAT activator, 30min before morphine or saline injection. Hippocampus, medial prefrontal cortex, nucleus accumbens and ventral tegmental area were harvested for Western analysis 24h after the last dose of morphine was injected. Morphine induced CPP in wild-type and EAAT3-/- mice. Gender is not a statistically significant factor to influence this behavior. This conditioned behavior extinguished after morphine administration was stopped for 8-9days in wild-type mice, while this extinction occurred 6days after discontinuation of morphine injection in EAAT3-/- mice. A small dose of morphine similarly reinstated the conditioned behavior in the wild-type and EAAT3-/- mice. Riluzole abolished morphine-induced CPP during the initial place preference. Morphine increased EAAT3 expression in the plasma membrane of medial prefrontal cortex, nucleus accumbens and ventral tegmental area but did not affect EAAT3 expression in the hippocampus. These results suggest that EAAT3 delays the extinction of morphine-induced CPP. EAAT activation may prevent the formation of morphine-induced CPP.

Liraglutide improves hypertension and metabolic perturbation in a rat model of polycystic ovarian syndrome.

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, with a prevalence of 5-8%. Type 2 diabetes and cardiovascular disease (CVD) are its long-term complications. Targeted therapies addressing both these complications together are lacking. Glucagon like peptide-1 (GLP-1) agonists that are used to treat type 2 diabetes mellitus have beneficial effects on the cardiovascular system. Hence we hypothesized that a GLP-1 agonist would improve both cardiovascular and metabolic outcomes in PCOS. To test this hypothesis, we used an established rat model of PCOS. Prepubertal female Sprague Dawley rats were sham-implanted or implanted s.c. with dihydrotestosterone (DHT) pellets (90 day release; 83 µg/day). At 12 wks of age, sham implanted rats received saline injections and the DHT treated animals were administered either saline or liraglutide (0.2 mg/kg s.c twice daily) for 4 weeks. Subgroups of rats were implanted with telemeters between 12-13 weeks of age to monitor blood pressure. DHT implanted rats had irregular estrus cycles and were significantly heavier than the control females at 12 weeks (mean± SEM 251.9±3.4 vs 216.8±3.4 respectively; p<0.05) and 4 weeks of treatment with liraglutide in DHT treated rats significantly decreased body weight (mean± SEM 294.75 ±3.2 in DHT+ saline vs 276.25±2.7 in DHT+ liraglutide group respectively; p<0.01). Liraglutide treatment in the DHT implanted rats significantly improved glucose excursion during oral glucose tolerance test (area under the curve: DHT+ saline 28674±310 vs 24990± 420 in DHT +liraglutide p <0.01). DHT rats were hypertensive and liraglutide treatment significantly improved mean arterial pressure. These results suggest that GLP-1 treatment could improve DHT-induced metabolic and blood pressure deficits associated with PCOS.

Transfusion of Old RBCs Induces Neuroinflammation and Cognitive Impairment.

OBJECTIVES: Transfusing RBCs stored for longer than 14 days (old RBC) in humans is common. This transfusion can injure organs, such as lungs and kidneys. We determined whether transfusion with old RBC injured brain. DESIGN: Prospective, controlled animal study. SETTING: University research laboratory. SUBJECTS: Adult male Sprague-Dawley rats. INTERVENTIONS: Six-month-old Sprague-Dawley rats lost 20% total blood volume and then received RBC prepared from equal volume of the lost blood. RBC was stored for 1 day (fresh RBC) or 7 days (old RBC, storage lesions similar to those of human RBC stored for 28 d). Some rats received IV cell-free hemoglobin. These rats were not subjected to hemorrhage and RBC transfusion. MEASUREMENTS AND MAIN RESULTS: Rats were subjected to Barnes maze and fear conditioning tests from 1 week after blood transfusion. Rats transfused with old RBC but not fresh RBC took a longer time to identify the target hole in the Barnes maze and had less context-related fear conditioning behavior than control rats. Old RBC significantly increased interleukin 6 and ionized calcium-binding adapter molecule 1 in the hippocampus at 24 hours after the transfusion. These effects were attenuated by sulforaphane and minocycline, an antibiotic with anti-inflammatory property. Old RBC solution had a higher concentration of cell-free hemoglobin. Sulforaphane increased haptoglobin, a chelator of cell-free hemoglobin. Rats that received cell-free hemoglobin had a pattern of neuroinflammation and impairment of learning and memory similar to that of rats that received old RBC. CONCLUSIONS: These results provide initial evidence to suggest that transfusion of old RBC induces neuroinflammation and impairment of learning and memory. These effects may be mediated by cell-free hemoglobin.

[Expression of glucocorticoid receptors alpha and beta in mononuclear cells of peripheral blood in patients with glucocorticoid-induced ocular hypertension].

OBJECTIVE: To study the expression of glucocorticoid receptors (alpha and beta) in mononuclear cells of peripheral blood (PBMCs) in patients with glucocorticoid-induced ocular hypertension (GIOH) and the relationship between of the expression of GRalpha and GRbeta in PBMCs and its susceptibility to GIOH. METHODS: Case control study. Thirty-two patients with anaphylactic conjunctivitis were enrolled in this study. All of whom were received topical application of 0.1% dexamethasone. The patients with the elevation of intraocular pressure (IOP) over 8 mm Hg(1 mm Hg = 0.133 kPa) or higher within two weeks were defined as GIOH and the others were considered as control group. There were no statistical difference in sex, average age, and baseline IOP between two groups. Each group consisted of sixteen patients. GRalpha and GRbeta mRNA (relative value) in PBMCs were detected with semi-quantitative reverse transcriptional polymerase chain reaction (RT-PCR), GRalpha and GRbeta protein (positive ratio) in PBMCs examined with fluorescent labelling flow cytometry. RESULTS: The GRalpha mRNA/GAPDH ratio of GIOH group was significantly (t = 3.872, P < 0.05) higher than that of control group (1.152 +/- 0.057 vs 1.048 +/- 0.031). The GRbeta mRNA/GAPDH of GIOH group was lower than that of control group's (1.055 +/- 0.034 vs 1.063 +/- 0.035), but was not statistically different (t = 0.419, P > 0.05). GRalpha positive percentage was significantly (t = 8.513, P < 0.01) higher in PBMCs of GIOH group than that of the control group (93.10 +/- 7.35)% vs (46.00 +/- 13.11)%, whereas GRbeta positive percentage was significantly (t = 4.842 P < 0.01) lower in PBMCs of GIOH group than that in control group (12.50 +/- 4.18)% vs (23.83 +/- 3.92)%. CONCLUSIONS: The higher expression of GRalpha in PBMCs in patients may have an implication of susceptibility to GIOH and warrant further investigation.