AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway.

BACKGROUND: Acute liver failure (ALF) is an unpredictable and life-threatening critical illness. The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure. METHODS: Animals were divided into 3 groups, normal, thioacetamide (TAA, ALF model) and TAA + AGK2. Cultured L02 cells were divided into 5 groups, normal, TAA, TAA + mitofusin 2 (MFN2)-siRNA, TAA + AGK2, and TAA + AGK2 + MFN2-siRNA groups. The liver histology was evaluated with hematoxylin and eosin staining, inositol-requiring enzyme 1 (IRE1), activating transcription factor 6ß (ATF6ß), protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and phosphorylated-PERK (p-PERK). C/EBP homologous protein (CHOP), reactive oxygen species (ROS), MFN2 and glutathione peroxidase 4 (GPX4) were measured with Western blotting, and cell viability and liver chemistry were also measured. Mitochondria-associated endoplasmic reticulum membranes (MAMs) were measured by immunofluorescence. RESULTS: The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis, which were reduced by AGK2 pre-treatment. In comparison to the normal group, apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ in the TAA-induced ALF model group were significantly increased, which were decreased by AGK2 pre-treatment. The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group, which were enhanced by AGK2 pre-treatment. Compared with the TAA-induced L02 cell, apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group. AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1, ATF6ß, p-PERK, CHOP, ROS and Fe2+ and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell. Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells. CONCLUSIONS: The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF.

Dietary ß-Hydroxy-ß-Methylbutyrate Supplementation Affects Growth Performance, Digestion, TOR Pathway, and Muscle Quality in Kuruma Shrimp (Marsupenaeus japonicas) Fed a Low Protein Diet.

An 8-week feeding trial was performed to evaluate the effects of dietary ß-hydroxy-ß-methylbutyrate (HMB) supplementation on growth performance and muscle quality of kuruma shrimp (Marsupenaeus japonicas) (initial weight: 2.00 ± 0.01 g) fed a low protein diet. The positive control diet (HP) with 490 g/kg protein and negative control diet (LP) with 440 g/kg protein were formulated. Based on the LP, 0.25, 0.5, 1, 2 and 4 g/kg ß-hydroxy-ß-methylbutyrate calcium were supplemented to design the other five diets named as HMB0.25, HMB0.5, HMB1, HMB2 and HMB4, respectively. Results showed that compared with the shrimp fed LP, the HP, HMB1 and HMB2 groups had significantly higher weight gain and specific growth rate, while significantly lower feed conversion ratio (p < 0.05). Meanwhile, intestinal trypsin activity was significantly elevated in the above three groups than that of the LP group. Higher dietary protein level and HMB inclusion upregulated the expressions of target of rapamycin, ribosomal protein S6 kinase, phosphatidylinositol 3-kinase, and serine/threonine-protein kinase in shrimp muscle, accompanied by the increases in most muscle free amino acids contents. Supplementation of 2 g/kg HMB in a low protein diet improved muscle hardness and water holding capacity of shrimp. Total collagen content in shrimp muscle increased with increasing dietary HMB inclusion. Additionally, dietary inclusion of 2 g/kg HMB significantly elevated myofiber density and sarcomere length, while reduced myofiber diameter. In conclusion, supplementation of 1-2 g/kg HMB in a low protein diet improved the growth performance and muscle quality of kuruma shrimp, which may be ascribed to the increased trypsin activity and activated TOR pathway, as well as elevated muscle collagen content and changed myofiber morphology caused by dietary HMB.

NOD2-mediated HDAC6/NF-κb signalling pathway regulates ferroptosis induced by extracellular histone H3 in acute liver failure.

Acute liver failure (ALF) is life-threatening and often associated with high mortality rates. The aim of the present study was to investigate whether extracellular histone H3 could induce ferroptosis in hepatic macrophages in ALF and explore its potential mechanism. RAW264.7 macrophages and C57BL/6 mice were used in this study. LPS, D-galactosamine (D-Gal), histone H3, histone H3 antibody, NOD2 agonist Muramyl Dipeptide (MDP) and HDAC6-siRNA were administered in this study. The key molecules of ferroptosis, NOD2, HDAC6 and the NF-κb pathway, were detected. In vitro, histone H3 was released into the extracellular environment from cell nucleus after LPS exposure. In addition, histone H3 could induce ferroptosis in RAW264.7 macrophages with increased level of Fe2+ and ROS and decreased levels of GPX4 and GSH. MDP further aggravated ferroptosis in RAW264.7 macrophages stimulated by histone H3, which was accompanied by elevated NOD2, HDAC6, p-P65 and IκBα. HDAC6-siRNA ameliorated ferroptosis in RAW264.7 macrophages induced by histone H3, which was accompanied by decreased levels of HDAC6, p-P65 and IκBα. However, HDAC6-siRNA did not alter NOD2 levels in RAW264.7 macrophages administered histone H3. In vivo, the levels of NOD2, HDAC6 the NF-κb pathway and ferroptosis were increased in ALF mice, which were downregulated by histone H3 antibody and upregulated by histone H3. Extracellular histone H3 could induce ferroptosis in hepatic macrophages in ALF by regulating theNOD2-mediated HDAC6/NF-κb signalling pathway.

Roles of vitamin K­dependent protein in biomineralization (Review).

Vitamin K (VK), a fat­soluble vitamin, is well known as an anticoagulant in the clinic. It is essential for the post­translational activation of VK­dependent proteins (VKDPs) because hydroquinone VK is a cofactor of glutamine carboxylase. At present, 17 VKDPs are known, which are mainly involved in coagulation and calcification. When Glu residues are carboxylated to Gla residues, these proteins gain a higher calcium­binding ability, which explains why VK has an important role in blood coagulation and biomineralization. However, the current view on the role of VK and several VKDPs in biomineralization remains inconsistent. For instance, conflicting results have been reported regarding the effect of osteocalcin gene knockout on the bone of mice; matrix Gla protein (MGP) promotes osteoblasts mineralization but inhibits vascular smooth muscle cell mineralization. The present review aimed to summarize the existing evidence that several VKDPs, including osteocalcin, MGP, Gla­rich protein and growth arrest specific 6 are closely related to calcification, including bone health, vascular calcification and lithiasis. The current review discussed these controversies and provided suggestions for future studies on VKDPs, i.e. taking into account dietary habits, geographical environments and genetic backgrounds.

The mechanism of blood coagulation induced by sodium dehydroacetate via the regulation of the mTOR/ERK pathway in rats.

Sodium dehydroacetate (DHA-S), a potent antifungal and antibacterial agent, is widely used in food, feed and cosmetics. However, recent studies have shown that DHA-S could pose a risk for human and animal health. We had previously reported that DHA-S could cause coagulation disorders in rats and chicken. In the present study, we further confirmed that DHA-S induced blood coagulation via VKORC1 and VKORC1L1 in rats, and elucidated the role played by mTOR/ERK signaling. The in vivo studies demonstrated that PT, APTT, and DHA-S content and relative protein expressions in tissues rebounded after drug withdrawal. In BRL-3A cells, 1.0 mM DHA-S increased the expression levels of mTOR, p-mTOR and p-ERK and decreased the levels of VKORC1, VKORC1L1 and Vitamin K. Rapamycin significantly decreased the expression levels of p-mTOR and p-ERK, while FR180204 (p-ERK Inhibition) lead to a decrease in p-ERK level. Rapamycin and FR180202 attenuated the inhibitory effect of DHA-S on VKORC1, VKORC1L1 and vitamin K levels. In addition, DHA-S increased the expression levels of mTOR, p-mTOR and p-ERK in male and female rat livers and prolonged PT and APTT. In summary, this study indicated that DHA-S induced blood coagulation via the modulation of the mTOR/ERK pathway in rats.

Mitochondrial calcium uniporter complex: Unveiling the interplay between its regulators and calcium homeostasis.

The mitochondrial calcium uniporter complex (MCUc), serving as the specific channel for calcium influx into the mitochondrial matrix, is integral to calcium homeostasis and cellular integrity. Given its importance, ongoing research spans various disease models to understand the properties of the MCUc in pathophysiological contexts, but reported a different conclusion. Therefore, this review delves into the profound connection between MCUc-mediated calcium transients and cellular signaling pathways, mitochondrial dynamics, metabolism, and cell death. Additionally, we shed light on the recent advancements concerning the structural intricacies and auxiliary components of the MCUc in both resting and activated states. Furthermore, emphasis is placed on novel extrinsic and intrinsic regulators of the MCUc and their therapeutic implications across a spectrum of diseases. Meanwhile, we employed molecular docking simulations and identified candidate traditional Chinese medicine components with potential binding sites to the MCUc, potentially offering insights for further research on MCUc modulation.

Global remote feature modulation end-to-end detection.

Object detector based on fully convolutional network achieves excellent performance. However, existing detection algorithms still face challenges such as low detection accuracy in dense scenes and issues with occlusion of dense targets. To address these two challenges, we propose an Global Remote Feature Modulation End-to-End (GRFME2E) detection algorithm. In the feature extraction phase of our algorithm, we introduces the Concentric Attention Feature Pyramid Network (CAFPN). The CAFPN captures direction-aware and position-sensitive information, as well as global remote dependencies of features in deep layers by combining Coordinate Attention and Multilayer Perceptron. These features are used to modulate the front-end shallow features, enhancing inter-layer feature adjustment to obtain comprehensive and distinctive feature representations.In the detector part, we introduce the Two-Stage Detection Head (TS Head). This head employs the First-One-to-Few (F-O2F) module to detect slightly or unobstructed objects. Additionally, it uses masks to suppress already detected instances, and then feeds them to the Second-One-to-Few (S-O2F) module to identify those that are heavily occluded. The results from both detection stages are merged to produce the final output, ensuring the detection of objects whether they are slightly obscured, unobstructed, or heavily occluded. Experimental results on the pig detection dataset demonstrate that our GRFME2E achieves an accuracy of 98.4%. In addition, more extensive experimental results show that on the CrowdHuman dataset, our GRFME2E achieves 91.8% and outperforms other methods.

The SIRT2-AMPK axis regulates autophagy induced by acute liver failure.

This study explores the role of SIRT2 in regulating autophagy and its interaction with AMPK in the context of acute liver failure (ALF). This study investigated the effects of SIRT2 and AMPK on autophagy in ALF mice and TAA-induced AML12 cells. The results revealed that the liver tissue in ALF model group had a lot of inflammatory cell infiltration and hepatocytes necrosis, which were reduced by SIRT2 inhibitor AGK2. In comparison to normal group, the level of SIRT2, P62, MDA, TOS in TAA group were significantly increased, which were decreased in AGK2 treatment. Compared with normal group, the expression of P-PRKAA1, Becilin1 and LC3B-II was decreased in TAA group. However, AGK2 enhanced the expression of P-PRKAA1, Becilin1 and LC3B-II in model group. Overexpression of SIRT2 in AML12 cell resulted in decreased P-PRKAA1, Becilin1 and LC3B-II level, enhanced the level of SIRT2, P62, MDA, TOS. Overexpression of PRKAA1 in AML12 cell resulted in decreased SIRT2, TOS and MDA level and triggered more autophagy. In conclusion, the data suggested the link between AMPK and SIRT2, and reveals the important role of AMPK and SIRT2 in autophagy on acute liver failure.

The relationship between nature exposure and depression among Chinese prisoners: a moderated mediation model.

Aim: This study examined the association between self-reported nature exposure and depression among Chinese prisoners, as well as the mediating and moderating effects of meaning in life and callous-unemotional (CU) traits, respectively. Background: Prisoners are more likely to experience depression than any other mental illness. Exposure to nature has been proposed as a highly cost-effective method of treating their depressive symptoms. However, the mechanism underlying the link between nature exposure and depression among prisoners needs further investigation, as the findings may provide new insights into how to address depression in incarcerated populations. Method: Data were collected through a survey conducted in four prisons in southern China from April to May 2022. The participants were 574 prisoners who anonymously completed four questionnaires about nature exposure, meaning in life, depression, and CU traits. Results: The results show that: (1) meaning in life significantly mediates the association between nature exposure and depression, and (2) CU traits moderate the connection between nature exposure and meaning in life. Conclusion: The current study uncovered that prisoners who contact more with the natural environment have a higher meaning in life and lower depression, and individuals with higher CU traits can benefit more from nature exposure.

The acetylation of MDH1 and IDH1 is associated with energy metabolism in acute liver failure.

The liver is the main organ associated with metabolism. In our previous studies, we identified that the metabolic enzymes malate dehydrogenase 1 (MDH1) and isocitrate dehydrogenase 1 (IDH1) were differentially expressed in ALF. The aim of this study was to explore the changes in the acetylation of MDH1 and IDH1 and the therapeutic effect of histone deacetylase (HDAC) inhibitor in acute liver failure (ALF). Decreased levels of many metabolites were observed in ALF patients. MDH1 and IDH1 were decreased in the livers of ALF patients. The HDAC inhibitor ACY1215 improved the expression of MDH1 and IDH1 after treatment with MDH1-siRNA and IDH1-siRNA. Transfection with mutant plasmids and adeno-associated viruses, identified MDH1 K118 acetylation and IDH1 K93 acetylation as two important sites that regulate metabolism in vitro and in vivo.