Current understanding of the cGAS-STING signaling pathway: Structure, regulatory mechanisms, and related diseases.

The innate immune system protects the host from external pathogens and internal damage in various ways. The cGAS-STING signaling pathway, comprised of cyclic GMP-AMP synthase (cGAS), stimulator of interferon genes (STING), and downstream signaling adaptors, plays an essential role in protective immune defense against microbial DNA and internal damaged-associated DNA and is responsible for various immune-related diseases. After binding with DNA, cytosolic cGAS undergoes conformational change and DNA-linked liquid-liquid phase separation to produce 2'3'-cGAMP for the activation of endoplasmic reticulum (ER)-localized STING. However, further studies revealed that cGAS is predominantly expressed in the nucleus and strictly tethered to chromatin to prevent binding with nuclear DNA, and functions differently from cytosolic-localized cGAS. Detailed delineation of this pathway, including its structure, signaling, and regulatory mechanisms, is of great significance to fully understand the diversity of cGAS-STING activation and signaling and will be of benefit for the treatment of inflammatory diseases and cancer. Here, we review recent progress on the above-mentioned perspectives of the cGAS-STING signaling pathway and discuss new avenues for further study.

Prior exposure to ciprofloxacin disrupts intestinal homeostasis and predisposes ayu ( Plecoglossus altivelis) to subsequent Pseudomonas plecoglossicida-induced infection.

With the rapid development of intensive farming, the aquaculture industry uses a great many antibiotics for the prevention and treatment of bacterial diseases. Despite their therapeutic functions, the overuse and accumulation of antibiotics also pose a threat to aquaculture organisms. In the present study, ayu ( Plecoglossus altivelis) was used as a fish model to study the impacts of ciprofloxacin (CIP) overuse on intestinal homeostasis and immune response during subsequent Pseudomonas plecoglossicida infection. Based on 16S rRNA gene amplification and Illumina sequencing, we found that CIP pre-exposure caused significant variation in intestinal microbiota, including increased species richness, altered microbiota composition and interaction networks, and increased metabolic dysfunction. Furthermore, immunohistochemical analysis indicated that CIP pre-exposure resulted in severe mucosal layer damage, goblet cell reduction, and epithelial cell necrosis of the intestinal barrier in infected ayu. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that disruption of intestinal homeostasis impaired systemic anti-infection immune responses in the intestine, gill, spleen, and head kidney, while inhibiting IL-1ß, TNF-α, and IL-10 expression and promoting TGF-ß expression. Our findings indicated that CIP administration can directly affect intestinal microbiota composition and intestinal integrity in ayu fish. This perturbation of intestinal homeostasis is likely responsible for the lower survival rate of hosts following subsequent infection as the capacity to mount an effective immune response is compromised. This study also provides preliminary clues for understanding the effects of antibiotic overuse on higher vertebrates through trophic transfer.

Molecular characterization, expression and functional analysis of large yellow croaker (Larimichthys crocea) peroxisome proliferator-activated receptor gamma.

The peroxisome proliferator-activated receptor gamma (PPARγ) are nuclear receptors with distinct roles in energy metabolism and immunity. Although extensively studied in mammals, immunomodulatory roles of this molecule in teleost fish remain to be investigated. In this study, large yellow croaker (Larimichthys crocea) PPARγ (LcPPARγ) sequence was cloned, which encodes a polypeptide of 541 amino acids that include signature domains belonging to the nuclear receptor superfamily. Phylogenetically, LcPPARγ was most closely related to PPARγ derived from European sea bass (Dicentrarchus labrax). Quantitative analysis shown a ubiquitous expression of this molecule, with highest expression level detected in the intestine. The expression of LcPPARγ was decreased in the intestine, muscle, body kidney, spleen and head kidney-derived monocytes/macrophages (MO/MФs) over the course of Vibrio alginolyticus (V. alginolyticus) infection. In contrast, an up-regulation of LcPPARγ was observed in head kidney-derived MO/MФs following docosahexaenoic acid (DHA) treatment. This increase in LcPPARγ leads to an up-regulation of LcCD11b and LcCD18 and an enhancement of complement-mediated phagocytosis. Furthermore, cytokine secretions of V. alginolyticus-stimulated MO/MФs were modulated following LcPPARγ activations that up-regulated the expression of LcIL-10, while decreased the expression of LcIL-1ß, LcTNF-α and LcTGF-ß1. Overall, our results indicated that LcPPARγ plays a role in regulating functions of MO/MФs and likely contribute to MO/MФs polarization.

Blood lead level in Chinese adults with and without coronary artery disease.

BACKGROUND: The Trial to Assess Chelation Therapy study found that edetate disodium (disodium ethylenediaminetetraacetic acid) chelation therapy significantly reduced the incidence of cardiac events in stable post-myocardial infarction patients, and a body of epidemiological data has shown that accumulation of biologically active metals, such as lead and cadmium, is an important risk factor for cardiovascular disease. However, limited studies have focused on the relationship between angiographically diagnosed coronary artery disease (CAD) and lead exposure. This study compared blood lead level (BLL) in Chinese patients with and without CAD. METHODS: In this prospective, observational study, 450 consecutive patients admitted to Beijing Anzhen Hospital with suspected CAD from November 1, 2018, to January 30, 2019, were enrolled. All patients underwent coronary angiography, and an experienced heart team calculated the SYNTAX scores (SXscore) for all available coronary angiograms. BLLs were determined with atomic absorption spectrophotometry and compared between patients with angiographically diagnosed CAD and those without CAD. RESULTS: In total, 343 (76%) patients had CAD, of whom 42% had low (0-22), 22% had intermediate (23-32), and 36% had high (≥ 33) SXscore. BLLs were 36.8 ± 16.95 µg/L in patients with CAD and 31.2 ± 15.75 µg/L in those without CAD (P = 0.003). When BLLs were categorized into three groups (low, middle, high), CAD prevalence increased with increasing BLLs (P < 0.05). In the multivariate regression model, BLLs were associated with CAD (odds ratio (OR): 1.023, 95% confidence interval (CI): 1.008-1.039; P = 0.0017). OR in the high versus low BLL group was 2.36 (95% CI: 1.29-4.42,P = 0.003). Furthermore, BLLs were independently associated with intermediate and high SXscore (adjusted OR: 1.050, 95% CI: 1.036-1.066; P < 0.0001). CONCLUSION: BLLs were significantly associated with angiographically diagnosed CAD. Furthermore, BLLs showed excellent predictive value for SXscore, especially for complex coronary artery lesions.

Revascularization versus drug therapy for coronary artery disease in patients aged over 80 years: a real-world study.

BACKGROUND: Revascularization for the treatment of coronary artery disease (CAD) is advancing rapidly and is used increasingly in old patients. This study aimed to compare the efficacy and safety of revascularization with drug therapy in CAD patients aged over 80 years at a real-world clinical setting. METHODS: A total of 501 CAD patients aged over 80 years were consecutively enrolled from January 2011 to January 2016 in Anzhen Hospital (Beijing, China), Capital Medical University. The patients were treated with percutaneous coronary intervention (PCI) (n=283), coronary artery bypass grafting (CABG) (n=106), or drug therapy (n=112). All-cause mortality, cardiovascular-related mortality, readmission rate, and Seattle Angina Questionnaire (SAQ) score were compared between the three treatment methods. RESULTS: A total of 411 patients (82.04%) were followed with a median duration of 25 months. All-cause mortality and cardiovascular-related mortality in the drug therapy group were significantly higher than the PCI and CABG groups (both P<0.05). Readmission rate for cardiovascular events in the CABG group was significantly lower than the PCI and drug therapy groups (both P<0.05). Scores of physical limitation, angina frequency, treatment satisfaction, and disease perception of the SAQ in the PCI and CABG groups were significantly higher than the drug therapy group (both P<0.05). Scores of angina stability did not differ significant between the three groups (P=0.127). CONCLUSIONS: Revascularization is superior to drug therapy in efficacy and safety in the treatment of oldest-old patients with CAD.

Clinical efficacy of different treatments and their impacts on the quality of life of octogenarians with coronary artery disease.

BACKGROUND: Coronary artery disease (CAD) in octogenarians (age of ≥80 years) has a high risk of mortality and high medical expenses. Research shows that the prevalence of CAD is higher among octogenarians than that among younger people, but few such patients undergo percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). This study aimed to evaluate different treatments with respect to their clinical effects and impacts on quality of life of octogenarians with CAD. METHODS: Data of 519 octogenarians with CAD consecutively treated at Beijing Anzhen Hospital, Capital Medical University (Beijing, China) from January 2010 to January 2016 were collected in this study. The patients were categorized into three groups based on the treatments they received: the PCI group (n = 292), CABG group (n = 110), and medical treatment group (n = 117). The followings were recorded during follow-up: clinical data, death (all-cause and cardiovascular-related), re-hospitalization time, Seattle Angina Questionnaire (SAQ) score, and occurrence of hemorrhagic events (cerebral bleeding, gastrointestinal bleeding, and dermal ecchymosis). RESULTS: The median follow-up duration was 25.0 (25th, 75th percentile: 17.0, 55.5) months among 417 patients. The all-cause death rates (28.2% vs. 12.0% and 14.6%, respectively) and cardiovascular-related death rates (15.4% vs. 3.8% and 6.4%, respectively) were significantly higher in the medical treatment group than those in the PCI group and CABG group (all P < 0.05). The re-hospitalization rate for cardiovascular events was significantly lower in the CABG group than those in the PCI group and medical treatment group (3.8% vs. 12.8% and 14.9%, respectively) (χ = 8.238, P = 0.018). The SAQ scores of physical limitation, angina frequency, treatment satisfaction, and disease perception were significantly higher in the PCI group and CABG group than those in the medical treatment group (all P < 0.05). No significant difference in the angina stability score was observed among the three groups (F = 3.179, P = 0.204). CONCLUSION: PCI and CABG result in reduced mortality and better quality of life in octogenarians with CAD.

Analysis of nickel distribution by synchrotron radiation X-ray fluorescence in nickel-induced early- and late-phase allergic contact dermatitis in Hartley guinea pigs.

BACKGROUND: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process and distribution of nickel in skin tissues with late phase and early phase of Ni-ACD to understand the mechanisms of metal allergy. METHODS: Forty Hartley guinea pigs were divided into four groups according to the NiSO4 sensitizing concentration and the NiSO4 challenged concentration: the 5% NiSO4-group, 5% to 10% (sensitization-challenge; late phase group); 10% NiSO4-group, 10% to 10% (sensitization-challenge; early-phase group); and the positive and negative controls. Pathological biopsies were performed on each group. The depth profile of nickel element concentration in the skin of guinea pigs was detected by synchrotron radiation micro X-ray fluorescence spectroscopy (SR-µ-XRF) and micro X-ray absorption near-edge spectroscopy (µ-XANES). RESULTS: In each section, the nickel element concentration in both the 5% NiSO4-group and 10% NiSO4-group was significantly higher than that in the negative control group. In the upper 300-µm section of skin for the early phase group, the nickel element concentration was significantly higher than that in the lower section of skin. In deeper sections (>200 µm) of skin, the concentration of nickel in the early phase group was approximately equal to that in the late phase group. The curve of the late phase group was flat, which means that the nickel element concentration was distributed uniformly by SR-µ-XRF. According to the XANES data for the 10% NiSO4 metal salt solution, structural changes occurred in the skin model sample, indicating that nickel was not present in the Ni aqueous ionic state but in the nickel-binding protein. CONCLUSIONS: This study showed that the distribution of the nickel element concentration in ACD skin tissue was different between the early phase and late phase groups. The nickel element was not present in the Ni aqueous ionic state but bound with certain proteins to form a complex in the stratum corneum in ACD model tissue.

[Construction and Identification of the cDNA Expression Library for Human Esophageal Cancer Cells].

OBJECTIVES: To construct a cDNA phage expression library for human esophageal cancer cells. METHODS: After the total RNA were obtained from esophageal cancer cells, the mRNA were separated with magnetic beads adsorption method, and the single-strand and double-strand cDNA were synthesized through reverse transcription. With the undesirable cDNA fragments removed, the remaining cDNA (linked withEcoR1 aptamer and phosphorylated its 5'end) combined with the carrier of T7 Select10-3b. The recombinant phage were packaged in vitro for preliminary cDNA library. PCR was used to identify the size of inserted cDNA. RESULTS: The constructed original cDNA phage expression library for human esophageal cancer cells was consisted of 2.01×106 pfu/mL bacteriophages with a recombination rate of 100%. The length of the inserted cDNA fragments were range from 300 bp to 1 500 bp. CONCLUSIONS: The cDNA phage expression library of human esophageal cell is successfully constructed to meet the currently recognized standards, and can be well used to screen cDNA-cloned genes of human esophageal cancer antigens by serological analysis of recombinantly expressed cDNA clone (SEREX).

[The characteristics of high density lipoprotein cholesterol and the relationship between high density lipoprotein cholesterol and the severity of coronary artery lesions in young men with acute myocardial infarction].

OBJECTIVE: To investigate the characteristics of high density lipoprotein cholesterol and the relationship between high density lipoprotein cholesterol and the severity of coronary artery lesions in young men with acute myocardial infarction (AMI). METHODS: We retrospectively studied 278 young men with acute myocardial infarction and compared with 208 non-CHD young men, 137 old men with AMI. All patients were admitted to hospital from Jan 2009 to Dec 2011 and undergone coronary angiography, and the clinic and coronary angiographic features were assessed.According to the result of coronary angiography, the patients were divided into three groups:the single, double and triple vessel lesions. The relation between systolic body mass index (BMI), hemoglobin (Hb), serum uric acid (UA), total cholesterol(TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), smoking history, essential hypertension, type 2 diabetes mellitus, familial history of early coronary artery disease with acute myocardial infarction and severity of coronary artery disease are observed.And observe the characteristics of HDL-C in the obesity group and the smoking group in young men based on body mass index and smoking history. RESULTS: (1) In young men with AMI group, the HDL-C levels was significantly lower than those in non-CHD young men group((1.00 ± 0.28) mmol/L vs (1.05 ± 0.23) mmol/L, P < 0.05).In young men with AMI group, the HDL-C levels was significantly lower than those in old men group with AMI ((1.00 ± 0.28) mmol/L vs (1.07 ± 0.30) mmol/L, P < 0.05);the HDL-C level in young AMI men with smoking history was significantly lower than those in young AMI men without smoking history ((0.98 ± 0.25) mmol/L vs (1.09 ± 0.40) mmol/L, P < 0.05);the HDL-C level in normal weight group is significantly higher than those in overweight and obesity groups in young AMI men ((1.30 ± 0.55) mmol/L vs (0.99 ± 0.22) mmol/L, (0.98 ± 0.29) mmol/L, P < 0.05). (2)The HDL-C level in the single lesions group was significantly lower than those in the double and triple vessel lesions groups ((1.06 ± 0.29) mmol/L vs (0.92 ± 0.20) mmol/L, (0.91 ± 0.26) mmol/L, P < 0.05). (3) Applying Logistic regression analysis, type 2 diabetes mellitus (OR = 35.784), essential hypertension (OR = 7.782), familial history of early coronary artery disease (OR = 4.613), low density lipoprotein cholesterol (OR = 2.496), smoking history (OR = 2.241), hemoglobin (OR = 1.042) and serum uric acid (OR = 1.005) are independent risk factors (P < 0.05) for young men with AMI, while high density lipoprotein cholesterol (OR = 0.147, P < 0.05) is a protective factor; low density lipoprotein cholesterol (OR = 2.095) and essential hypertension (OR = 1.042) are independent risk factors (P < 0.05) for young men with multiple vessel lesions in AMI, while high density lipoprotein cholesterol (OR = 0.071, P < 0.05) is a protective factor. CONCLUSION: High density lipoprotein cholesterol are protective factors for young men with AMI and multiple vessel lesions in young men with AMI.