Polystyrene nanospheres-induced hepatotoxicity in swamp eel (Monopterus albus): From biochemical, pathological and transcriptomic perspectives.

As ubiquitous emerging pollutants, microplastics (MPs) in aquatic environments have aroused critical global concerns. Despite the occurrence and characteristics of MPs in freshwater agroecosystems well-described by our previous study, their ecotoxicological implications in Monopterus albus remains unfathomed. Herein, we dissected toxic effects and mechanisms of PS-NPs exposure against M. albus hepatic tissues at concentrations of 0.5 (L), 5 (M), 10 (H) mg/L for 28 days using physiochemical measurements, histopathological analysis and transcriptomic sequencing. Results showed that upon PS-NPs treatments, levels of ROS, MDA, 8-OHdG and MFO activity were significantly enhanced relative to the control (C) group, while SP content and T-AOC activity were dramatically suppressed, suggesting ROS burst, lipid peroxidation and DNA damage may occur in liver tissues. This oxidative damage further triggered impaired hepatic function and histopathology, disordered lipid metabolism and hepatocyte apoptosis, as reflected by significantly diminished activities of GPT, GOT, ACP, AKP and LDH, paralleled with augmented levels of TG, TC and HSI as well as Cytc and Caspase-3,8,9 activities. Noticeably, concentration-dependent rises of apoptotic rate, vacuolar degeneration and lipid deposition were manifest in TUNEL, H&E and ORO staining. In addition, a total of 375/475/981 up-regulated as well as 260/611/1422 down-regulated DEGs in C vs L, C vs M and C vs H categories were identified based on RNA-seq, respectively. These DEGs were significantly annotated and enriched into GO terms (membrane, cytoplasm, response to stimuli, oxidation-reduction process) as well as KEGG pathways (ether lipid metabolism, apoptosis, chemical carcinogenesis-reactive oxygen species, non-alcoholic fatty liver disease). Moreover, signaling cascades Keap1-Nrf2, p53 and PPAR were either substantially initiated or dysregulated to orchestrate PS-NPs hepatotoxicity featuring oxidative damage, hepatocyte apoptosis and lipid steatosis. Collectively, this study not only expounded on toxicological mechanisms whereby PS-MPs exerted deleterious effects on M. albus, but also pointed to ecological risks of PS-MPs-induced hepatoxicity and lipid steatosis in this commercially-important species.

Lactoferrin Relieves Deoxynivalenol-Induced Oxidative Stress and Inflammatory Response by Modulating the Nrf2/MAPK Pathways in the Liver.

Deoxynivalenol (DON), one of the most common mycotoxins contaminating food and feed, has been shown to induce hepatotoxicity. Lactoferrin (LF) enriched in human milk is a critical functional food component and performs the hepatoprotection function. Here, we aimed to explore whether dietary LF supplementation can protect from DON-induced hepatotoxicity and uncover the underlying mechanism in mice and alpha mouse liver 12 (AML12) hepatocytes. In vivo results revealed that LF alleviated DON-induced liver injury, reflected by repairing the hepatic histomorphology and decreasing the plasma alanine aminotransferase (ALT) level and the number of blood white blood cells (WBC) and neutrophils (Neu). Moreover, LF decreased the hepatic reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation and enhanced the hepatic GSH-px activity and protein expression of Nrf2 and GPX4 to reverse the DON-induced hepatic oxidative stress. Furthermore, LF downregulated the pro-inflammatory-response-related gene expressions (IL1ß, TNFα, and Tlr4) and the phosphorylation levels of IKK, IκBα, and p38 in the liver of DON-exposed mice. Additionally, in vitro studies confirmed that LF ameliorated the DON-induced oxidation-reduction imbalance, inflammatory responses, and associated core modulators of the Nrf2 and MAPK pathways in DON-induced hepatotoxicity. In conclusion, LF performs hepatic antioxidative and anti-inflammatory functions by regulating the Nrf2/MAPK signaling pathways, thus reducing DON-induced hepatotoxicity.

Development of Specific Monoclonal Antibodies against Porcine RIG-I-like Receptors Revealed the Species Specificity.

The RIG-I-like receptors (RLRs) play critical roles in sensing and combating viral infections, particularly RNA virus infections. However, there is a dearth of research on livestock RLRs due to a lack of specific antibodies. In this study, we purified porcine RLR proteins and developed monoclonal antibodies (mAbs) against porcine RLR members RIG-I, MDA5 and LGP2, for which one, one and two hybridomas were obtained, respectively. The porcine RIG-I and MDA5 mAbs each targeted the regions beyond the N-terminal CARDs domains, whereas the two LGP2 mAbs were both directed to the N-terminal helicase ATP binding domain in the Western blotting. In addition, all of the porcine RLR mAbs recognized the corresponding cytoplasmic RLR proteins in the immunofluorescence and immunochemistry assays. Importantly, both RIG-I and MDA5 mAbs are porcine specific, without demonstrating any cross-reactions with the human counterparts. As for the two LGP2 mAbs, one is porcine specific, whereas another one reacts with both porcine and human LGP2. Thus, our study not only provides useful tools for porcine RLR antiviral signaling research, but also reveals the porcine species specificity, giving significant insights into porcine innate immunity and immune biology.

First phase ejection fraction in aortic stenosis: A useful new measure of early left ventricular systolic dysfunction.

In aortic stenosis (AS), a left ventricular (LV) ejection fraction (EF) <50% or symptoms are class I indications for aortic valve intervention. However, an EF <50% may be too conservative since subendocardial fibrosis may already have developed. An earlier marker of LV systolic dysfunction is therefore needed and first phase EF (EF1) is a promising new candidate. It is the EF measured over early systole to the point of maximum transaortic blood flow. It may be low in the presence of preserved total LV EF since the heart may compensate by recruiting myosin motors in later systole. The EF1 is inversely related to the grade of AS and directly related to markers of subendocardial fibrosis like late gadolinium enhancement on cardiac magnetic resonance scanning. A reduced EF1 (<25%) predicts adverse clinical events better that total EF and global longitudinal strain. We suggest that it is worth exploring as an indication for surgery in patients with asymptomatic severe AS.

Determinants and prognostic value of echocardiographic first-phase ejection fraction in aortic stenosis.

OBJECTIVE: First-phase ejection fraction (EF1) is a novel measure of early left ventricular systolic dysfunction. We investigated determinants of EF1 and its prognostic value in aortic stenosis. METHODS: EF1 was measured retrospectively in participants of an echocardiography/cardiovascular magnetic resonance cohort study which recruited patients with aortic stenosis (peak aortic velocity of ≥2 m/s) between 2012 and 2014. Linear regression models were constructed to examine variables associated with EF1. Cox proportional hazards were used to determine the prognostic power of EF1 for aortic valve replacement (AVR, performed as part of clinical care in accordance with international guidelines) or death. RESULTS: Total follow-up of the 149 participants (69.8% male, 70 (65-76) years, mean gradient 33 (21-42) mm Hg) was 238 029 person-days. Sixty-seven participants (45%) had a low baseline EF1 (<25%) despite normal ejection fraction (67% (62%-71%)). Patients with low EF1 had more severe aortic stenosis (mean gradient 39 (34-45) mm Hg vs 24 (16-35) mm Hg, p<0.001) and more myocardial fibrosis (indexed extracellular volume (iECV) (24.2 (19.6-28.7) mL/m2 vs 20.6 (16.8-24.3) mL/m2, p=0.002; late gadolinium enhancement (LGE) prevalence 52% vs 20%, p<0.001). Zva, iECV and infarct LGE were independent predictors of EF1. EF1 improved post-AVR (n=57 with post-AVR EF1 available, baseline 16 (12-24) vs follow-up 27% (22%-31%); p<0.001). Low baseline EF1 was an independent predictor of AVR/death (HR 5.6, 95% CI 3.4 to 9.4), driven by AVR. CONCLUSION: EF1 quantifies early, potentially reversible systolic dysfunction in aortic stenosis, is associated with global afterload and myocardial fibrosis, and is an independent predictor of AVR.

Hepatic leukocyte immunoglobulin-like receptor B4 (LILRB4) attenuates nonalcoholic fatty liver disease via SHP1-TRAF6 pathway.

Nonalcoholic fatty liver disease (NAFLD) is an increasingly prevalent liver pathology characterized by hepatic steatosis and commonly accompanied by systematic inflammation and metabolic disorder. Despite an accumulating number of studies, no pharmacological strategy is available to treat this condition in the clinic. In this study, we applied extensive gain- and loss-of-function approaches to identify the key immune factor leukocyte immunoglobulin-like receptor B4 (LILRB4) as a negative regulator of NAFLD. The hepatocyte-specific knockout of LILRB4 (LILRB4-HKO) exacerbated high-fat diet-induced insulin resistance, glucose metabolic imbalance, hepatic lipid accumulation, and systematic inflammation in mice, whereas LILRB4 overexpression in hepatocytes showed a completely opposite phenotype relative to that of LILRB4-HKO mice when compared with their corresponding controls. Further investigations of molecular mechanisms demonstrated that LILRB4 recruits SHP1 to inhibit TRAF6 ubiquitination and subsequent inactivation of nuclear factor kappa B and mitogen-activated protein kinase cascades. From a therapeutic perspective, the overexpression of LILRB4 in a genetic model of NAFLD, ob/ob mice, largely reversed the inherent hepatic steatosis, inflammation, and metabolic disorder. CONCLUSION: Targeting hepatic LILRB4 to improve its expression or activation represents a promising strategy for the treatment of NAFLD as well as related liver and metabolic diseases. (Hepatology 2018;67:1303-1319).

An adenylyl cyclase like-9 gene (NlAC9) influences growth and fecundity in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).

The cAMP/PKA intracellular signaling pathway is launched by adenylyl cyclase (AC) conversion of adenosine triphosphate (ATP) to 3', 5'-cyclic AMP (cAMP) and cAMP-dependent activation of PKA. Although this pathway is very well known in insect physiology, there is little to no information on it in some very small pest insects, such as the brown planthopper (BPH), Nilaparvata lugens Stål. BPH is a destructive pest responsible for tremendous crop losses in rice cropping systems. We are investigating the potentials of novel pest management technologies from RNA interference perspective. Based on analysis of transcriptomic data, the BPH AC like-9 gene (NlAC9) was up-regulated in post-mating females, which led us to pose the hypothesis that NlAC9 is a target gene that would lead to reduced BPH fitness and populations. Targeting NlAC9 led to substantially decreased soluble ovarian protein content, yeast-like symbiont abundance, and vitellogenin gene expression, accompanied with stunted ovarian development and body size. Eggs laid were decreased and oviposition period shortened. Taken together, our findings indicated that NlAC9 exerted pronounced effects on female fecundity, growth and longevity, which strongly supports our hypothesis.

Cardiac valve disease and low-dose dopamine agonist therapy: an artefact of reporting bias?

INTRODUCTION: Chronic low-dose cabergoline treatment for microprolactinoma may cause cardiac valve pathology, but the evidence is contradictory. We investigated whether the expectation of the echocardiographer could influence the report. METHODS: Transthoracic echocardiograms from 40 patients aged 49·3 ± 9·6 (mean ± SD) years (Men:Women 7:33) on long-term cabergoline and bromocriptine therapy (duration 9·94 ± 4·5 years) were randomly assigned to two groups of echocardiographers so that each echocardiogram was reported twice. One group was told that 'the patients were control subjects' (Group A) and the other that 'the patients were on dopamine agonist therapy which is known to cause valve disease' (Group B). An observer who was blind to the group scored the reports for regurgitation at each valve (scores 0-4; max 16 per case). RESULTS: Mean total regurgitation score was significantly higher in Group B (1·43 ± 1·28; P = 0·014) than in Group A (0·73 ± 1·30). The difference was mainly from reporting trivial regurgitation: (mitral 16 vs 5, P = 0·005; tricuspid 17 vs 6, P = 0·007 and pulmonary 8 vs 1, P = 0·013). Mild regurgitation was uncommon (mitral 1 vs 1 and tricuspid 3 vs 6). Moderate regurgitation occurred in only one case and was associated with restriction of the leaflets consistent with the effects of cabergoline. Valve thickening was not reported in Group A, but in 9 (23%) mitral and 4 (10%) aortic valves in Group B. CONCLUSION: Long-term, low-dose dopamine agonist therapy rarely causes cardiac valve disease, but operator bias can lead to over-reporting of both valve thickening and trivial regurgitation.