Background Environmental noise pollution is serious, and there are few studies on the effects of long-term noise exposure during sleep on cognitive function and possible biological clock mechanism. Objective To explore the cognitive impairment induced by noise exposure during sleep in mice and possible biological clock mechanism, and to provide a theoretical basis for the protection against noise exposure. Methods Twenty male C57BL/6J mice were randomly divided into a control group and a noise-exposed group, 10 mice in each group. The noise-exposed group was exposed to sleep-period noise using a noise generator for 12 h (08:00–20:00) per day for a total of 30 d. The calibrated noise intensity was set at 90 dB. No intervention was imposed on the control group. At the end of the noise exposure, cognitive function of mice was examined using the new object recognition experiment and the open field test, and the hippocampal tissue damage of mice were evaluated by Nissl staining, ionized calcium binding adaptor molecule 1 (Iba1) immunofluorescence staining, and real-time fluorescence quantitative PCR for inflammatory factors and biological clock genes. Oxidative stress indicators in the hippocampus of mice were also detected by assay kit. Results After noise exposure during sleep period, the results of new object recognition experiment showed that the discrimination index of mice in the noise-exposed group was 0.06±0.04, which was significantly lower than that of the control group (0.65±0.13) (P<0.05). The results of open field test showed that the central activity distance of the noise-exposed group was (242.20±176.10) mm, which was significantly lower than that of the control group, (1548.00±790.30) mm (P < 0.05), and the central activity time of the noise-exposed group was (0.87±0.64) s, which was significantly lower than that of the control group, (6.00±2.86) s (P < 0.05). The Nissl staining results showed that compared with the control group, neurons in the hippocampus of the noise-exposed mice were shrunken, deeply stained, disorganized, and loosely connected. The immunofluorescence results showed that microglia in the hippocampus of the noise-exposed mice were activated and the expression of Iba1 was significantly increased compared with those of the control group (P<0.05). The real-time PCR results of showed that the mRNA levels of the biological clock genes Clock, Per2, and Rev-erbα were significantly increased compared with those of the control group (P<0.05), and the mRNA level of Per1 was significantly decreased compared with that of the control group (P<0.05); and the mRNA levels of IL-18, IL-6, iNOS, and NLRP3 in the hippocampal tissues of mice were significantly increased compared with those of the control group (P<0.05). The results of oxidative stress evaluation showed that compared with the control group, reduced glutathione content was significantly reduced in the noise-exposed group (P<0.001). Conclusion Noise exposure during sleep period can lead to the destabilization of biological clock genes in hippocampal tissues and trigger hippocampal neuroinflammation, which can lead to the activation of microglia and cause cognitive impairment in mice.

Background Long-term exposure to noise during sleep may has adverse effects on metabolic system, and liver lipid metabolism is closely related to circadian clock genes. Objective To investigate the effects of long-term noise exposure during sleep on liver circadian clock and lipid metabolism in mice and its related mechanism. Methods Twenty C57BL/6J male mice were randomly divided into two groups: a noise exposure group and a control group with 10 mice in each group. The mice in the noise exposure group were exposed to white noise at 90 dB sound pressure level (SPL) for 30 consecutive days, 8 h a day, from 9:00 to 17:00. The mice in the control group were exposed to background noise ≤40 dB SPL. After noise exposure, the animals were neutralized at 14:00 (ZT6) and 2:00 (ZT18), 5 animals at each time spot, and the liver tissues were collected. Total cholesterol and triglyceride in liver were determined by cholesterol oxidase method and glycerol phosphate oxidase method respectively. The expressions of circadian clock genes (Clock, Bmal1, Rev-erbα, and Rev-erbβ) and lipid metabolism genes (Srebp1c, Hmgcr, Fasn, Lxrα, Acc1, and Chrebp) in liver were detected by quantitative real-time PCR. Results Compared with the control group, the content of total cholesterol in liver in the noise exposure group increased by 48% (P<0.05) and the content of liver triglyceride increased by 61% (P<0.05) at ZT18. The mRNA expression levels of circadian clock genes Clock and Bmal1 in the noise exposure group was significantly increased at ZT18 and decreased at ZT6 (P<0.05). The mRNA expression level of Rev-erbα decreased at both ZT6 and ZT18 (P<0.05). The mRNA expression level of Rev-erbβ had no significant change at ZT6 and ZT18. The mRNA expression levels of liver lipid metabolism related genes Srebp1c, Hmgcr, Chrebp, and Lxrα in the noise exposure group were higher than those in the control group at ZT18 (P<0.05). The mRNA expression levels of Acc1 and Fasn showed no significant change at ZT6, then an upward trend at ZT18, but no significant difference between the two time spots (P>0.05). Conclusion Long-term noise exposure during sleep can cause circadian clock and lipid metabolism disorders in mice. Among them, suppression of key circadian clock genes may be associated with Rev-erbα-mediated upregulation of the nuclear receptors Srebp1c and Chrebp for lipid synthesis and deposition in the liver, resulting in lipid metabolism disorder.

Objective·To investigate the expression of miR-146a in peripheral blood CD4+T lymphocytes of patients with rheumatoid arthritis(RA)and its correlation with inflammatory cytokines such as tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6).Methods·A total of 30 active RA patients who received medical treatment and 30 healthy controls who underwent physical examinations at the People's Hospital of Longhua,Shenzhen from August 2019 to July 2021 were selected.Peripheral blood mononuclear cells(PBMCs)and CD4+T lymphocytes were isolated from venous blood extracted from RA patients and healthy controls,respectively.Quantitative real-time PCR(qPCR)was used to detect the expression of miR-146a in peripheral blood CD4+T lymphocytes,and enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of TNF-α and IL-6.After transfection of the peripheral blood CD4+T lymphocytes of RA patients with miR-146a mimic,the expression of miR-146a,TNF-α and IL-6 was detected again.The correlations between miR-146a expression and TNF-α and IL-6 expression in RA patients,both before and after transfection,were analyzed by using Pearson correlation coefficient.Results·Before transfection with miR-146a mimic,the expression levels of miR-146a,TNF-α and IL-6 in peripheral blood CD4+T lymphocytes of RA patients were significantly higher than those of healthy controls(all P＜0.001).After transfection,the expression of miR-146a in peripheral blood CD4+T lymphocytes of RA patients was significantly higher,and the expression of TNF-α and IL-6 was significantly lower(all P＜0.001).The results of Pearson correlation analysis showed that the expression of miR-146a in peripheral blood CD4+T lymphocytes of RA patients,both before and after transfection,was positively correlated with the expression of TNF-α and IL-6,respectively(r=0.959,P＜0.001;r=0.916,P＜0.001;r=0.971,P＜0.001;r=0.861,P＜0.001).Conclusion·miR-146a can regulate the levels of TNF-α and IL-6 in peripheral blood CD4+T lymphocytes of RA patients,indicating that miR-146a may play a role in the pathogenesis of RA.

Objective:To investigate the effects of 40 Hz and 70 Hz frequency flash stimulation on the ability of learning memory and autonomous exploratory in young rats.Methods:Twenty-seven SPF grade male SD rats aged 19-21 days were divided into control group (Ctr group), 40 Hz group and 70 Hz group with 9 in each group according to the random number table.The rats in Ctr group were not given flash stimulation, while rats in the 40 Hz and 70 Hz group were received 40 Hz, 70 Hz flash stimulation (1.5 h/d for 39 days), respectively.The Morris water maze experiment was used to assess the learning and memory ability of rats, and the open field experiment was used to evaluate the ability of autonomous exploratory of rats.Nissl staining was used to assess the morphology of Nissl bodies in the hippocampus CA1 region of the rats.The local field potentials (LFPs) collected from the primary visual cortex (V1 area) region by electrophysiological experiments was used to verify the synchronization of flash evoked neural oscillations.SPSS 23.0 software was used for statistical analysis.The repeated measures ANOVA and one-way ANOVA were used to analyze normal distribution measurement data, and LSD and Tamhane tests were used for further pairwise comparison.The Kruskal-Wallis test was used for non-normal distribution measurement data.Results:(1) The flash stimulation of 40 Hz and 70 Hz both can effectively caused synchronization of neural oscillations in the primary visual cortex of healthy young rats.(2) The results of repeated measures ANOVA analysis showed that there was no interaction effect of grouping and time in the escape latency of young rats in the Morris water maze positioning navigation phase( F=1.326, P>0.05 ). The escape latency had time main effect ( F=40.025, P<0.05), but no grouping main effect ( F=2.039, P>0.05). With the increase of learning days, the escape latency of young rats in each group decreased significantly.There was no interaction effect of grouping and time in the total distance of young rats ( F=2.029, P>0.079). It had time main effect ( F=32.052, P<0.05), but not grouping main effect ( F=2.390, P>0.05) on total distance.With the increase of learning days, the total distance of young rats in each group significantly shortened.On the 6th day of the Morris water maze experiment, there was no statistically significant difference among groups in terms of time in the target quadrant and the number of crossing platforms ( F=2.511, 0.802, both P>0.05). The results of the open field experiment showed that the total distance traveled in the center of young rats in each group was statistically significant ( H=8.935, P<0.05), the total distance traveled in the center in the 70 Hz group (3.80 (2.25, 6.93) m)was significantly longer than that in the 40 Hz group (0.80 (0.72, 1.46) m), P<0.05). The percentage of time spent in the center was statistically significant in the three groups ( H=11.050, P<0.05). Young rats in the 70 Hz group spent significantly higher percentage of time in the center(3.20(2.43, 8.30)) than those in the 40 Hz group (0.95 (0.37, 1.06 ), P<0.05 ). (3) Nissl staining results showed that Nissl bodies in the hippocampal CA1 area of young rats in Ctr, 40 Hz and 70 Hz group were all arranged neatly and tightly, no edema was found in the surrounding stroma, and no obvious inflammatory cell infiltration was found. Conclusion:70 Hz frequency flash stimulation may promote the ability of learning memory and autonomous exploratory of young rats.

Dihydroflavonol 4-reductase (DFR) plays an essential role in the biosynthesis of anthocyanin and regulation of plant flower color. Based on the transcriptome data of Cistanche tubulosa (Schenk) Wight, a full-length cDNA sequence of CtDFR gene was cloned by reverse transcription-polymerase chain reaction (RT-PCR). CtDFR contains an open reading frame (ORF) of 1 263 bp which encodes 420 amino acids with a predicted molecular weight of 47.5 kDa. The sequence analysis showed that CtDFR contains a nicotinamide adenine dinucleotide phosphate (NADPH) binding domain and a specific substrate binding domain. The expression analysis indicated that CtDFR was highly expressed in red and purple flowers, and the relative expression levels were 4.04 and 19.37 times higher than those of white flowers, respectively. The recombinant CtDFR protein was expressed in E.coli BL21 (DE3) using vector pET-28a-CtDFR and was purified. In vitro enzyme activity analysis, CtDFR could reduce three types of dihydroflavonols including dihydrokaempferol, dihydroquercetin, and dihydromyricetin to leucopelargonidin, leucocyanidin and leucodelphinidin. Subcellular localization analysis showed that CtDFR was mainly localized in the cytoplasm. These results demonstrate that CtDFR plays an important role in regulation of flower color in C. tubulosa and make a valuable contribution for the further investigation on the regulation mechanism of C. tubulosa (Schenk) Wight flower color.

To maintain the precision and stability of the efficacy of classical formulas, this study compared the origins and specifications of Bupleuri Radix and revealed the precise application regularity of Bupleurum chinense(Beichaihu) and Bupleurum scorzonerifolium(Nanchaihu) in classical formulas. The efficacy and indications of formulas with Bupleuri Radix as the sovereign drug in the Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun) were investigated. The difference in the efficacy of Bupleuri Radix as well as the differences in the chemical composition, and liver-protecting and lipid-lowering effects of the decoctions of Beichaihu and Nanchaihu were analyzed with LC-MS technology based on the CCl_4-induced liver injury model in mice and sodium oleate-induced HepG2 hyperlipidemia cell model. The results showed that seven classical formulas with Bupleuri Radix as the sovereign drug in the Treatise on Cold Damage and Miscellaneous Diseases were mainly used in the treatment of digestive, metabolic, immune, circulatory, and other diseases. Bupleuri Radix mainly played the functions of protecting the liver, benefiting the gallbladder, and lowering the lipid, and had different focuses in different formulas. There were 14 differential components in the decoctions of Beichaihu and Nanchaihu, and the chemical structures of 11 components were identified, including 10 saponins and one flavonoid. The results of the liver-protecting efficacy experiment showed that compared with the Nanchaihu decoction, Beichaihu decoction could reduce the serum aspartate aminotransferase(AST) activity in liver injury model mice(P<0.01). The results of the lipid-lowering efficacy experiment proved that Beichaihu and Nanchaihu decoctions both showed highly significant differences in lowering the total cholesterol(TC) and triglyceride(TG) content in HepG2 cells(P<0.01), and Nanchaihu decoction was superior to Beichaihu decoction in lowering the lipid. The results of this study preliminarily proved that there were differences in chemical composition, and liver-protecting and lipid-lowering effects of Beichaihu and Nanchaihu decoctions, indicating that it was necessary to determine the precise origin of Bupleuri Radix in the clinical formulation of traditional Chinese medicine. The study provides a scientific basis for both precise clinical medication and purpose-based accurate quality evaluation of traditional Chinese medicine in clinical application.
Animals ; Mice ; Liver ; Aspartate Aminotransferases ; Bupleurum

Objective:To explore the prognostic factors predicting the recovery of elderly patients with hospital-acquired pneumonia(HAP).Methods:Data of HAP inpatients aged over 60 years in the First Affiliated Hospital of Nanjing Medical University between October 2015 and October 2020 were collected.Body mass index(BMI), neutrophil/lymphocyte rate(NLR), Charlson Comorbidity Index(CCI), Combined Comorbidity Score(CCS)and other data were retrospectively analyzed.The predictive value of the related factors was evaluated by using the Student's t test, the Logistic regression model and the receiver operating characteristic curve(ROC). Results:A total of 200 cases were enrolled in this study, and grouped into survival group(n=158)and death group(n=42). There were significant differences between the death group and the survival group in length of age, BMI hospital stay, state of consciousness, swallowing function, indwelling gastric tube, the use of proton pump inhibitors, leukocyte count, lymphocyte count, neutrophil count, hemoglobin, NLR, albumin, alanine aminotransferase, aspartate aminotransferase, D-dimer, C-reaction protein, procalcitonin(all P<0.05). Scores of CCI and CCS were higher in the death group than in the survival group[(6.79±2.86) vs.(3.42±1.98), (6.21±3.08) vs.(1.66±1.94), t=-7.193, -9.116, both P<0.001]. Multivariate Logistic analysis showed that age>86 years( OR=1.155, 95% CI: 1.014-1.316), BMI<21.77 kg/m 2( OR=0.651, 95% CI: 0.480-0.883), neutrophil count>10.10×10 9/L( OR=1.208, 95% CI: 1.025-1.422), C-reaction protein>59.32 mg/L( OR=1.055, 95% CI: 1.018-1.093), CCS>6.21 scores( OR=2.859, 95% CI: 1.559-5.244)were risk factors for death inpatients aged 60 years and older with HAP.Area under the ROC curve showed that CCS could better predict the mortality of elderly patients than CCI, and the areas under the ROC curve were 0.831(95% CI: 0.753-0.909)and 0.898(95% CI: 0.850-0.946)respectively(both P< 0.001). Conclusions:The elderly patients with HAP are inclined to multiplecomplications and high mortality rates.Combined application of multiple assessment systems and clinical indicators can improve the ability to predict the outcome of HAP.

Background Noise has multiple negative effects on the organism, and gut microbes are influenced by the environment and are closely associated with the development of diseases. Currently, the effects of chronic noise exposure on intestinal microbiota are poorly understood. Objective To investigate the effects of noise exposure on the structure of rat gut microbiota and to make predictions of gut microbiota function. Methods Male Wistar rats (6 weeks old, 160-180 g) were randomly divided into control, NE_95dB, and NE_105dB groups, 10 rats in each group. Rats in the NE_95dB and the NE_105dB groups were exposed to noise at 95 dB sound pressure level (SPL) and 105 dB SPL, respectively, 4 h per day for consecutive 30 d, while the control group was exposed to background noise. Feces were collected after the last noise exposure for intestinal microbiota detection. Based on the 16S ribosomal RNA (rRNA) gene sequencing method, the diversity and structure of microbiota in rat intestinal contents were analyzed and compared. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to predict functions of the identified intestinal microbiota genes. Results Significant differences were found in the microbial structure of the rat gut after the designed noise exposure. In the α diversity results, there was a statistically significant difference in the Chao1 index between the NE_95dB group and the NE_105dB group (P=0.02), while there were no statistically significant differences in the Shannon and Simpson indexes between the noise exposure groups and the control group (P>0.05). The β diversity analysis results showed significant differences in species abundance between the control group and the noise exposure groups (P=0.001). Further species analysis results showed that the relative abundances of the Ruminococcaceae_NK4A214_group (P<0.05) and Peptococcaceae_unclassified (P<0.01) at the genus level were significantly higher in the NE_105dB group, and the relative abundance of Parasutterella (P<0.05) was significantly higher in the NE_95dB group compared to the control group. In addition, the Ruminococcaceae_NK4A214_group (P<0.05) was also significantly higher in the NE_105dB group compared to the NE_95dB group. The PICRUSt functional prediction analysis results showed that there were eight differential pathways between the control group and the NE_95dB group, in which D-arginine and D-ornithine metabolism, ascorbate and aldarate metabolism, carotenoid biosynthesis, glycerophospholipid metabolism, mineral absorption, NOD-like receptor signaling pathway and non-homologous end-joining were significantly down-regulated, and nucleotide metabolism was significantly up-regulated. There were 38 differential pathways between the control group and the NE_105dB group. Among them, D-arginine and D-ornithine metabolism, and mineral absorption were the differential metabolic pathways in both noise exposure groups, and both were down-regulated relative to the control group. Conclusion Chronic noise exposure could alter structure of rat gut microbiota and may affect metabolic functions of multiple microbiota genes.

Background Noise can cause not only auditory system injury, but also liver damage. However, the biomarkers and pathological mechanism of noise-induced liver injury are not clear yet. Objective To observe the effect of noise on the morphological structure and functions of rat liver. Methods A total of 30 Wistar rats were randomly divided into a normal control group, a low noise exposure group [(95 dB sound pressure level (SPL)], and a high noise exposure group (105 dB SPL). After 30 days of noise exposure, blood was collected, and livers were harvested and fixed. The pathological changes of livers were observed. The levels of biochemical indicators of liver function, blood glucose, and blood lipid were measured. Serum metabolites were detected by ultra-high-pressure liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS). Differential metabolite markers and metabolic pathways were identified. Results Compared with the control group, the body weight gain decreased in the low noise group and the high noise group after noise exposure (P<0.001, P<0.05). The pathological results showed that noise caused the rat livers’ morphological and structural damage at various degrees, and damage of the high noise exposure group was more serious. Compared with the control group, the serum levels of aspartate aminotransferase, albumin, and glycosylated serum protein in the low noise exposure group were increased (P<0.05), but the total bile acid level was decreased (P<0.05). The serum levels of alanine aminotransferase, aspartate aminotransferase, albumin, triglyceride, low density lipoprotein, and glycosylated serum protein in the high noise group exposure were increased (P<0.05), but the glucose level was decreased (P<0.05). In the serum metabolomics analysis, 11 differential metabolites were screened out in the low noise exposure group, which were mainly enriched in 3 pathways (thiamine metabolism, primary bile acid biosynthesis, and bile secretion) related to liver metabolism. Four differential metabolites were screened out in the high exposure noise group, which were mainly enriched in four significantly different metabolic pathways (insulin signaling pathway, non-alcoholic fatty liver disease, bile secretion, and insulin secretion). All the metabolic pathways involved in bile acid secretion and metabolism. Conclusion Nosie exposure can not only damage the liver structure of rats, but also affects the metabolism functions of liver. The mechanism may be related to bile acid secretion metabolic pathway.

Objective: To study the protective effects of metformin on noise-induced hearing loss (NIHL) and its differential protein omics expression profile. Methods: In January 2021, 39 male Wistar rats were randomly divided into control group, noise exposure group and metformin+noise exposure group, with 13 rats in each group. Rats in the noise exposure group and metformin+noise exposure group were continuously exposed to octave noise with sound pressure level of 120 dB (A) and center frequency of 8 kHz for 4 h. Rats in the metformin+noise exposure group were treated with 200 mg/kg/d metformin 3 d before noise exposure for a total of 7 d. Auditory brainstem response (ABR) was used to test the changes of hearing thresholds before noise exposure and 1, 4, 7 d after noise exposure in the right ear of rats in each group. Tandem mass tag (TMT) quantitative proteomics was used to identify and analyze the differentially expressed protein in the inner ear of rats in each group, and it was verified by immunofluorescence staining with frozen sections. Results: The click-ABR thresholds of right ear in the noise exposure group and metformin+noise exposure group were significantly higher than those in the control group 1, 4, 7 d after noise exposure (P<0.05) . The click-ABR threshold of right ear in the metformin+noise exposure group were significantly lower than that in the noise exposure group (P<0.05) . Compared with the noise exposure group, 1035 up-regulated proteins and 1145 down-regulated proteins were differentially expressed in the metformin+noise exposure group. GO enrichment analysis showed that the significantly differentially expressed proteins were mainly involved in binding, molecular function regulation, signal transduction, and other functions. Enrichment analysis of KEGG pathway revealed that the pathways for significant enrichment of differentially expressed proteins included phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) signaling pathway, focal adhesion, diabetic cardiomyopathy, mitogen, and mitogen-activated protein kinase (MAPK) signaling pathway. Immunofluorescence experiments showed that compared with the noise exposure group, the fluorescence intensity of insulin-like growth factor 1 receptor (IGF1R) in the metformin+noise exposure group was increased, and the fluorescence intensity of eukaryotic translation initiation factor 4E binding protein 1 (eIF4EBP1) was decreased. Conclusion: Noise exposure can lead to an increase in rat hearing threshold, and metformin can improve noise-induced hearing threshold abnormalities through multiple pathways and biological processes.
Animals ; Auditory Threshold/physiology* ; Cochlea ; Ear, Inner ; Evoked Potentials, Auditory, Brain Stem/physiology* ; Hearing Loss, Noise-Induced/prevention & control* ; Male ; Metformin/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Rats ; Rats, Wistar