AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

The complex pathological mechanism of dry eye involves multiple pathways, such as immunity and inflammation, and requires an integral research program to control the whole picture. Various histological techniques can elucidate the complex physio-pathological state of organisms from a holistic and global perspective, thus providing more comprehensive biological information. Mass spectrometry can sensitively detect the changes of protein content in tear samples, providing convenience for proteomics research of dry eye. At present, proteomics has demonstrated its application in the identification of dry eye types, severity grading, and therapeutic effect evaluation. In addition, proteomics combined with metabolomics and microbiomics can more comprehensively explain the pathogenesis of dry eye. In the future, proteomics is expected to provide more powerful support for the precise diagnosis and treatment of dry eye, taking an advantage in targeted therapy.

BACKGROUND:Oxidative injury is considered to be one of the important factors of cerebral ischemia-reperfusion injury.Superoxide dismutase 2(SOD2)is a key mitochondrial antioxidant molecule,and fenofibrate can regulate the expression of SOD2 by activating peroxisome proliferator-activated receptor α. OBJECTIVE:To explore whether the mechanism of fenofibrate in the treatment of cerebral ischemia-reperfusion injury depends on the expression of SOD2. METHODS:The TALENs system was used to construct SOD2 transgenic mice.The transgenic mice were genotyped by PCR and DNA sequencing techniques.The expression of SOD2 protein in transgenic mice was detected by western blot assay.Wild-type and SOD2 transgenic mice were randomly divided into four groups:wild-type control group(n=6),wild-type fenofibrate group(n=6),SOD2 transgenic control group(n=5)and SOD2 transgenic fenofibrate group(n=5).A mouse model of middle cerebral artery occlusion was prepared using the suture-occlusion method.After 90 minutes of ischemia,the thread was removed to reperfuse cerebral blood flow for 30 minutes.A cerebral blood flow monitor was used to monitor local cerebral blood flow.Brain tissue slices were taken for 2,3,5-triphenyltetrazolium chloride staining to analyze the situation of cerebral infarction in each group. RESULTS AND CONCLUSION:After PCR and DNA sequencing analysis,nine SOD2+/+ transgenic mice were successfully constructed.After cerebral ischemia-reperfusion,the wild-type fenofibrate group showed partial recovery of cerebral blood flow and significantly reduced cerebral infarction volume compared with the wild-type control group(P<0.001).There was no significant difference in cerebral blood flow and cerebral infarction volume between the SOD2 transgenic fenofibrate group and the SOD2 transgenic control group.The SOD2 transgenic control was superior to the wild-type control group in terms of improving cerebral blood flow and cerebral infarction(P<0.001).There were also no significant differences in cerebral blood flow and cerebral infarction volume between the wild-type fenofibrate group and the SOD2 transgenic control group and between the wild-type fenofibrate group and the SOD2 transgenic fenofibrate group.To conclude,the expression of SOD2 is one of the mechanisms of fenofibrate in the treatment of cerebral ischemia-reperfusion injury.

Objective:To prepare rabbit polyclonal antibodies against respiratory syncytial virus (RSV) N protein and use them as the detection antibodies to establish a N-ELISA-based method for rapid detection of neutralizing antibodies.Methods:A plasmid of pET30a-N for the expression of RSV N protein was constructed. After purification, the protein was immunized into New Zealand rabbits to prepare polyclonal antibodies, which were used as the detection antibodies. Positive serum samples were diluted and used to neutralize RSV (100 TCID 50/well). Hep-2 cells were inoculated and cultured, and then the cells were fixed with 80% acetone. ELISA was performed to detect RSV N protein in infected cells. When the absorbance value of a well was below the cut-off value, it was regarded as the positive well in the neutralization test. The highest dilution of a positive well serum was the neutralizing antibody titer. After optimizting the antibody dilution, detection time, cell density and the duration of neutralization, the method for neutralizing antibody detection was established based on N-ELISA. The established method was verified by analyzing the influences of different cell generations and edge effects, and calculating the accuracy, repeatability and precision. The correlation between the established method and microneutralization method was analyzed by detecting human RSV IgG-positive serum. Results:The plasmid pET30a-N was successfully constructed, and the expressed N protein showed high purity and good specificity. After the third immunization, the antibody titer in rabbit serum was 1∶51 200, and the antibodies could specifically bind to RSV. The prepared rabbit anti-RSV N polyclonal antibodies had a titer of 1∶51 200, and showed good specificity. The neutralizing antibodies could be detected on day 4 with the established method, and the duration of neutralization was shortened to 30 min. Cell generations and the position of wells in the 96-well plate (edge well and non-edge well) had no significant effect on the method, and the repeatability, precision and accuracy of the method were good. In the detection of 64 RSV IgG-positive human serum samples by the established method and microneutralization method, the correlation coefficient was 0.929 6, indicating a good positive correlation between the two methods.Conclusions:A N-ELISA-based method for rapid neutralizing antibody detection is successfully established, which can be used to evaluate the serum antibody level after RSV vaccination.

Respiratory syncytial virus (RSV) is one of the major pathogens of acute respiratory infections, becoming a huge global burden. Virus-receptor interactions play a key role in the pathogenesis of RSV infection. The distribution of receptors influences the cellular and the tissue tropism of RSV as well as the viral replication and proliferation in the host. However, the RSV receptors are currently unknown, which is one of the reasons that hinders the development of RSV vaccines and therapeutic drugs. In this study, the existing RSV receptors are reviewed with the hope to provide ideas for the research of RSV vaccines and therapeutic drugs.

Objective:To evaluate the relationship between glutathione S-transferase μ1 (GSTM1) and the apoptosis signal-regulating kinase 1 (ASK1)-c-Jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinase (MAPK) signaling pathway during therapeutic hypothermia-induced reduction of cerebral ischemia-reperfusion injury (CIRI) in rats.Methods:One hundred clean-grade healthy male Sprague-Dawley rats, aged 8 weeks, weighing 260-280 g, were divided into 5 groups ( n=20 each) using a random number table method: sham operation group (S group), cerebral ischemia-reperfusion group (I/R group), therapeutic hypothermia group (H group), GSTM1 inhibitor+ therapeutic hypothermia group (IH group), and GSTM1 inhibitor + ASK1 inhibitor + therapeutic hypothermia group (IAH group). CIRI model was developed by occlusion of the left middle cerebral artery for 2 h, followed by restoration of the blood flow. A nylon thread was inserted into the internal carotid artery and advanced cephalad until resistance was met. The brain temperature was maintained at 36-37 ℃ during surgery. In H group, the head and neck were wiped with 75% alcohol immediately after reperfusion, and the brain temperature was maintained at 32-33℃ for 3 h, and the rest procedures were the same as those previously described in I/R group. In IH group, GSTM1 inhibitor itaconic acid 8.6 mg/kg was intraperitoneally injected at 24 and 1 h before developing the model, and the rest procedures were the same as those previously described in H group. In IAH group, ASK1 inhibitor selonsertib 10 mg/kg was given orally once a day for 4 consecutive days starting from 4 days before developing the model, and the rest procedures were the same as those previously described in IH group. Modified Neurological Severity Score (mNSS) was assessed at 24 h of reperfusion, then the rats were sacrificed and brains were harvested for microscopic examination of brain infarction, neuronal morphology (using HE staining) and for determination of the expression of GSTM1, ASK1, phosphorylated ASK1 (p-ASK1), JNK, phosphorylated JNK (p-JNK), p-38 MAPK and phosphorylated p-38 MAPK (p-p38 MAPK) (by Western blot) and neuronal apoptosis (by TUNEL assay). The percentage of the infarct size was calculated using TTC staining. The apoptosis rate was calculated. Results:Compared with S group, the mNSS, apoptosis rate of neurons, percentage of the cerebral infarct size, p-ASK1/ASK1 ratio, p-JNK/JNK ratio and p-p38 MAPK/p38 MAPK ratio were significantly increased, and the expression of GSTM1 was down-regulated in I/R group ( P<0.05). Compared with I/R group and IH group, the mNSS, apoptosis rate of neurons, percentage of the cerebral infarct size, p-ASK1/ASK1 ratio, p-JNK/JNK ratio and p-p38 MAPK/p38 MAPK ratio were significantly decreased, the expression of GSTM1 was up-regulated ( P<0.05), and the neuronal injury was significantly attenuated in H group. Compared with IH group, the mNSS, apoptosis rate of neurons, percentage of the cerebral infarct size, p-ASK1/ASK1 ratio, p-JNK/JNK ratio and p-p38 MAPK/p38 MAPK ratio were significantly decreased ( P<0.05), no significant change was found in GSTM1 expression ( P>0.05), and the neuronal damage was significantly attenuated in IAH group. Conclusions:The mechanism by which therapeutic hypothermia alleviates CIRI is related to up-regulating the expression of GSTM1 and inhibiting the activation of the ASK1-JNK-p38 MAPK signaling pathway in rats.

The killing effect of radiation therapy on healthy cells has led to the creation of targeted radionuclide therapy,which effectively reduces the damage to surrounding normal cells.At present,alpha(α)and beta(β)radionuclides are the research hotspots of targeted therapy.Numerous preclinical and clinical studies have shown that radiation therapy not only has local anti-tumor effects,but also exerts systemic anti-tumor effects by triggering the body's immune response.This paper describes in detail the characteristics and clinical applications of commonly used radionuclides,and discusses the mechanism of radiation-triggered body immune response as well as the related research on the combined use of radiation therapy,targeted radionuclide therapy and immunotherapy.

Objective To investigate the therapeutic mechanism of Pterocarya hupehensis Skan total flavonoids(PHSTF)for rheumatoid arthritis(RA).Methods Twenty-five male SD rats were randomly divided into normal control group,RA model group,PHSTF treatment(45 and 90 mg/kg)groups,and Tripterygium glycosides(TPG)tablet(10 mg/kg)group(n=5).Except for those in the normal control group,all the rats were subjected to collagen-induced arthritis(CIA)modeling using a secondary immunization method,after which PHSTF and TPG were administered via gavage once daily for 4 weeks.After the treatments,serum levels of TNF-α and IL-1β were measured using ELISA,and ankle joint pathologies were assessed with HE staining;the expression of citrullinated histone H3(Cit-H3),a neutrophil extracellular trap(NET)marker,in the ankle joints was evaluated with immunohistochemistry.In primary cultures of rat peripheral blood neutrophils stimulated with phorbol ester(PMA),the effects of PHSTF(100 and 200 μg/mL)on the expressions of Cit-H3,peptidylarginine deiminase 4(PADI4),neutrophil elastase(NE),and myeloperoxidase(MPO)were examined with Western blotting;immunofluorescence assay was used to observe Cit-H3 expression and NET formation in the cells.Results In the CIA rat models,PHSTF significantly alleviated ankle swelling,decreased serum levels of TNF-α and IL-1β,improved histopathological changes in the ankle joints,and reduced Cit-H3 expression in both the serum and ankle joint cartilage.In the isolated rat neutrophils,PHSTF showed no significant effect on cell viability but strongly inhibited PMA-induced NET release.Conclusion PHSTF can alleviate RA by inhibiting the formation of NETs.

Background::While type 2 diabetes mellitus (T2DM) is considered a putative causal risk factor for coronary artery disease (CAD), the intrinsic link underlying T2DM and CAD is not fully understood. We aimed to highlight the importance of integrated care targeting both diseases by investigating the phenotypic and genetic relationships between T2DM and CAD.Methods::We evaluated phenotypic associations using data from the United Kingdom Biobank ( N = 472,050). We investigated genetic relationships by leveraging genomic data conducted in European ancestry for T2DM, with and without adjustment for body mass index (BMI) (T2DM: Ncase/ Ncontrol = 74,124/824,006; T2DM adjusted for BMI [T2DM adjBMI]: Ncase/ Ncontrol = 50,409/523,897) and for CAD ( Ncase/ Ncontrol = 181,522/984,168). We performed additional analyses using genomic data conducted in multiancestry individuals for T2DM ( Ncase/ Ncontrol = 180,834/1,159,055). Results::Observational analysis suggested a bidirectional relationship between T2DM and CAD (T2DM→CAD: hazard ratio [HR] = 2.12, 95% confidence interval [CI]: 2.01–2.24; CAD→T2DM: HR = 1.72, 95% CI: 1.63–1.81). A positive overall genetic correlation between T2DM and CAD was observed ( rg = 0.39, P = 1.43 × 10 -75), which was largely independent of BMI (T2DM adjBMI–CAD: rg = 0.31, P = 1.20 × 10 –36). This was corroborated by six local signals, among which 9p21.3 showed the strongest genetic correlation. Cross-trait meta-analysis replicated 101 previously reported loci and discovered six novel pleiotropic loci. Mendelian randomization analysis supported a bidirectional causal relationship (T2DM→CAD: odds ratio [OR] = 1.13, 95% CI: 1.11-1.16; CAD→T2DM: OR = 1.12, 95% CI: 1.07-1.18), which was confirmed in multiancestry individuals (T2DM→CAD: OR = 1.13, 95% CI: 1.10-1.16; CAD→T2DM: OR = 1.08, 95% CI: 1.04-1.13). This bidirectional relationship was significantly mediated by systolic blood pressure and intake of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, with mediation proportions of 54.1% (95% CI: 24.9-83.4%) and 90.4% (95% CI: 29.3-151.5%), respectively. Conclusion::Our observational and genetic analyses demonstrated an intrinsic bidirectional relationship between T2DM and CAD and clarified the biological mechanisms underlying this relationship.