APT1-Mediated Depalmitoylation Regulates Hippocampal Synaptic Plasticity.

Palmitoylation may be relevant to the processes of learning and memory, and even disorders, such as post-traumatic stress disorder and aging-related cognitive decline. However, underlying mechanisms of palmitoylation in these processes remain unclear. Herein, we used acyl-biotin exchange, coimmunoprecipitation and biotinylation assays, and behavioral and electrophysiological methods, to explore whether palmitoylation is required for hippocampal synaptic transmission and fear memory formation, and involved in functional modification of synaptic proteins, such as postsynapse density-95 (PSD-95) and glutamate receptors, and detected if depalmitoylation by specific enzymes has influence on glutamatergic synaptic plasticity. Our results showed that global palmitoylation level, palmitoylation of PSD-95 and glutamate receptors, postsynapse density localization of PSD-95, surface expression of AMPARs, and synaptic strength of cultured hippocampal neurons were all enhanced by TTX pretreatment, and these can be reversed by inhibition of palmitoylation with palmitoyl acyl transferases inhibitors, 2-bromopalmitate and N-(tert-butyl) hydroxylamine hydrochloride. Importantly, we also found that acyl-protein thioesterase 1 (APT1)-mediated depalmitoylation is involved in palmitoylation of PSD-95 and glutamatergic synaptic transmission. Knockdown of APT1, not protein palmitoyl thioesterase 1, with shRNA, or selective inhibition, significantly increased AMPAR-mediated synaptic strength, palmitoylation levels, and synaptic or surface expression of PSD-95 and AMPARs. Results from hippocampal tissues and fear-conditioned rats showed that palmitoylation is required for synaptic strengthening and fear memory formation. These results suggest that palmitoylation and APT1-mediated depalmitoylation have critical effects on the regulation of glutamatergic synaptic plasticity, and it may serve as a potential target for learning and memory-associated disorders.SIGNIFICANCE STATEMENT Fear-related anxiety disorders, including post-traumatic stress disorder, are prevalent psychiatric conditions, and fear memory is associated with hyperexcitability in the hippocampal CA1 region. Palmitoylation is involved in learning and memory, but mechanisms coupling palmitoylation with fear memory acquisition remain poorly understood. This study demonstrated that palmitoylation is essential for postsynapse density-95 clustering and hippocampal glutamatergic synaptic transmission, and APT1-mediated depalmitoylation plays critical roles in the regulation of synaptic plasticity. Our study revealed that molecular mechanism about downregulation of APT1 leads to enhancement of AMPAR-mediated synaptic transmission, and that palmitoylation cycling is implicated in fear conditioning-induced synaptic strengthening and fear memory formation.

IL-33/ST2 axis of human amnion fibroblasts participates in inflammatory reactions at parturition.

BACKGROUND: Inflammation of the fetal membranes is an indispensable event of labor onset at both term and preterm birth. Interleukin-33 (IL-33) is known to participate in inflammation via ST2 (suppression of tumorigenicity 2) receptor as an inflammatory cytokine. However, it remains unknown whether IL-33/ST2 axis exists in human fetal membranes to promote inflammatory reactions in parturition. METHODS: The presence of IL-33 and ST2 and their changes at parturition were examined with transcriptomic sequencing, quantitative real-time polymerase chain reaction, Western blotting or immunohistochemistry in human amnion obtained from term and preterm birth with or without labor. Cultured primary human amnion fibroblasts were utilized to investigate the regulation and the role of IL-33/ST2 axis in the inflammation reactions. A mouse model was used to further study the role of IL-33 in parturition. RESULTS: Although IL-33 and ST2 expression were detected in both epithelial and fibroblast cells of human amnion, they are more abundant in amnion fibroblasts. Their abundance increased significantly in the amnion at both term and preterm birth with labor. Lipopolysaccharide, serum amyloid A1 and IL-1ß, the inflammatory mediators pertinent to labor onset, could all induce IL-33 expression through NF-κB activation in human amnion fibroblasts. In turn, via ST2 receptor, IL-33 induced the production of IL-1ß, IL-6 and PGE2 in human amnion fibroblasts via the MAPKs-NF-κB pathway. Moreover, IL-33 administration induced preterm birth in mice. CONCLUSION: IL-33/ST2 axis is present in human amnion fibroblasts, which is activated in both term and preterm labor. Activation of this axis leads to increased production of inflammatory factors pertinent to parturition, and results in preterm birth. Targeting the IL-33/ST2 axis may have potential value in the treatment of preterm birth.

METTL3 promotes proliferation of goat endometrial epithelial cells by regulating CTGF in an m6A-dependent manner†.

N6-methyladenosine (m6A), an epigenetic modification on RNAs, plays an important role in many physiological and pathological processes. However, the involvement of m6A in goat uterus during early pregnancy remains largely unknown. In this study, we found that the total m6A level was increasing in goat uterus as early pregnancy progressed. Methyltransferase-like 3 (METTL3) is a core catalytic subunit of the m6A methyltransferase. We thus determined the expression and regulation of METTL3 in goat uterus. METTL3 was highly expressed in the luminal and glandular epithelia from day 16 (D16) to D25 of pregnancy, and it could be up-regulated by estrogen and progesterone in goat uterus and primary endometrial epithelial cells (EECs). In EECs, knockdown or overexpression of METTL3 resulted in a significant decrease or increase of cell proliferation, respectively. METTL3 knockdown reduced the m6A level of not only total RNA but also connective tissue growth factor (CTGF) mRNA. Luciferase assay suggested that METTL3 might target the potential m6A sites in the 3'untranslated region (3'UTR) of CTGF mRNA. Moreover, METTL3 positively regulated CTGF expression, and CTGF knockdown significantly counteracted the promoting effect of METTL3 overexpression on EEC proliferation. Collectively, METTL3 is dynamically expressed in goat uterus and can affect EEC proliferation by regulating CTGF in an m6A-dependent manner. Our results will lay a foundation for further studying the crucial mechanism of METTL3-mediated m6A modification in goat uterus during early pregnancy.

Magnetic resonance spectroscopy and liquid chromatography-mass spectrometry metabolomics study may differentiate pre-eclampsia from gestational hypertension.

OBJECTIVE: To investigate the findings of magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), and serum metabolomics for differentiating pre-eclampsia (PE) from gestational hypertension (GH). METHODS: This prospective study enrolled 176 subjects including a primary cohort with healthy non-pregnant women (HN, n = 35), healthy pregnant women (HP, n = 20), GH (n = 27), and PE (n = 39) and a validation cohort with HP (n = 22), GH (n = 22), and PE (n = 11). T1 signal intensity index (T1SI), apparent diffusion coefficient (ADC) value, and the metabolites on MRS were compared. The differentiating performances of single and combined MRI and MRS parameters for PE were evaluated. Serum liquid chromatography-mass spectrometry (LC-MS) metabolomics was investigated by sparse projection to latent structures discriminant analysis. RESULTS: Increased T1SI, lactate/creatine (Lac/Cr), and glutamine and glutamate (Glx)/Cr and decreased ADC value and myo-inositol (mI)/Cr in basal ganglia were found in PE patients. T1SI, ADC, Lac/Cr, Glx/Cr, and mI/Cr yielded an area under the curves (AUC) of 0.90, 0.80, 0.94, 0.96, and 0.94 in the primary cohort, and of 0.87, 0.81, 0.91, 0.84, and 0.83 in the validation cohort, respectively. A combination of Lac/Cr, Glx/Cr, and mI/Cr yielded the highest AUC of 0.98 in the primary cohort and 0.97 in the validation cohort. Serum metabolomics analysis showed 12 differential metabolites, which are involved in pyruvate metabolism, alanine metabolism, glycolysis, gluconeogenesis, and glutamate metabolism. CONCLUSIONS: MRS is expected to be a noninvasive and effective tool for monitoring GH patients to avoid the development of PE. KEY POINTS: • Increased T1SI and decreased ADC value in the basal ganglia were found in PE patients than in GH patients. • Increased Lac/Cr and Glx/Cr, and decreased mI/Cr in the basal ganglia were found in PE patients than in GH patients. • LC-MS metabolomics showed that the major differential metabolic pathways between PE and GH were pyruvate metabolism, alanine metabolism, glycolysis, gluconeogenesis, and glutamate metabolism.

Amnion-derived serum amyloid A1 participates in sterile inflammation of fetal membranes at parturition.

OBJECTIVES: Sterile inflammation of fetal membranes is an indispensable event of normal parturition. However, triggers of sterile inflammation are not fully resolved. Serum amyloid A1 (SAA1) is an acute phase protein produced primarily by the liver. Fetal membranes can also synthesize SAA1 but its functions are not well defined. Given the role of SAA1 in the acute phase response to inflammation, we postulated that SAA1 synthesized in the fetal membranes may be a trigger of local inflammation at parturition. METHODS: The changes of SAA1 abundance in parturition were studied in the amnion of human fetal membranes. The role of SAA1 in chemokine expression and leukocyte chemotaxis was examined in cultured human amnion tissue explants as well as primary human amnion fibroblasts. The effects of SAA1 on monocytes, macrophages and dendritic cells were investigated in cells derived from a human leukemia monocytic cell line (THP-1). RESULTS: SAA1 synthesis increased significantly in human amnion at parturition. SAA1 evoked multiple chemotaxis pathways in human amnion fibroblasts along with upregulation of a series of chemokines via both toll-like receptor 4 (TLR4) and formyl peptide receptor 2 (FPR2). Moreover, SAA1-conditioned medium of cultured amnion fibroblasts was capable of chemoattracting virtually all types of mononuclear leukocytes, particularly monocytes and dendritic cells, which reconciled with the chemotactic activity of conditioned medium of cultured amnion tissue explants collected from spontaneous labor. Furthermore, SAA1 could induce the expression of genes associated with inflammation and extracellular matrix remodeling in monocytes, macrophages and dendritic cells derived from THP-1. CONCLUSIONS: SAA1 is a trigger of sterile inflammation of the fetal membranes at parturition.

Association between cadmium exposure and pulmonary function reduction: Potential mediating role of telomere attrition in chronic obstructive pulmonary disease patients.

BACKGROUND: Environmental cadmium (Cd) exposure is linked to pulmonary function injury in the general population. But, the association between blood Cd concentration and pulmonary function has not been investigated thoroughly in chronic obstructive pulmonary disease (COPD) patients, and the potential mechanisms are unclear. METHODS: All eligible 789 COPD patients were enrolled from Anhui COPD cohort. Blood specimens and clinical information were collected. Pulmonary function test was conducted. The subunit of telomerase, telomerase reverse transcriptase (TERT), was determined through enzyme linked immunosorbent assay (ELISA). Blood Cd was measured via inductively coupled-mass spectrometer (ICP-MS). RESULTS: Blood Cd was negatively and dose-dependently associated with pulmonary function. Each 1-unit increase of blood Cd was associated with 0.861 L decline in FVC, 0.648 L decline in FEV1, 5.938 % decline in FEV1/FVC %, and 22.098 % decline in FEV1 % among COPD patients, respectively. Age, current-smoking, self-cooking and higher smoking amount aggravated Cd-evoked pulmonary function decrease. Additionally, there was an inversely dose-response association between Cd concentration and TERT in COPD patients. Elevated TERT obviously mediated 29.53 %, 37.50 % and 19.48 % of Cd-evoked FVC, FEV1, and FEV1 % declines in COPD patients, respectively. CONCLUSION: Blood Cd concentration is strongly associated with the decline of pulmonary function and telomerase activity among COPD patients. Telomere attrition partially mediates Cd-induced pulmonary function decline, suggesting an underlying mechanistic role of telomere attrition in pulmonary function decline from Cd exposure in COPD patients.

Paradoxical Induction of ALOX15/15B by Cortisol in Human Amnion Fibroblasts: Implications for Inflammatory Responses of the Fetal Membranes at Parturition.

Inflammation of the fetal membranes is an indispensable event of parturition, with increasing prostaglandin E2 (PGE2) synthesis as one of the ultimate products that prime labor onset. In addition to PGE2, the fetal membranes also boast a large capacity for cortisol regeneration. It is intriguing how increased PGE2 synthesis is achieved in the presence of increasing amounts of classical anti-inflammatory glucocorticoids in the fetal membranes at parturition. 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) synthesized by lipoxygenase 15/15B (ALOX15/15B) has been shown to enhance inflammation-induced PGE2 synthesis in amnion fibroblasts. Here, we examined whether glucocorticoids could induce ALOX15/15B expression and 15(S)-HETE production to promote PGE2 synthesis in amnion fibroblasts at parturition. We found that cortisol and 15(S)-HETE abundance increased parallelly in the amnion at parturition. Cortisol induced ALOX15/15B expression and 15(S)-HETE production paradoxically in amnion fibroblasts. Mechanism study revealed that this paradoxical induction was mediated by p300-mediated histone acetylation and interaction of glucocorticoid receptor with transcription factors CREB and STAT3. Conclusively, cortisol regenerated in the fetal membranes can paradoxically induce ALOX15/15B expression and 15(S)-HETE production in human amnion fibroblasts, which may further assist in the induction of PGE2 synthesis in the inflammatory responses of the fetal membranes for parturition.

Copper-Catalyzed Remote Enantioselective Sulfonylation of Yne-Allylic Esters with Sodium Sulfinates.

Impressive progress has been made in the copper-catalyzed asymmetric propargylic substitution (APS) reaction, but its use in remote asymmetric yne-allylic substitution remains a challenging topic. Herein, we report the first remote enantioselective copper-catalyzed sulfonylation of yne-allylic esters with sodium sulfinates. The reaction is assumed to occur via a copper-vinylvinylidene species as the key reactive intermediate. The use of readily available starting materials, the mild reaction conditions, and the excellent regio-, enantio- and stereoselectivity, as well as broad substrate scope (>70 examples), show the practicality and attractiveness of this method.

Target Deoxyribonucleic Acid-Recycled Lighting-Up Amplifiable Ratiometric Fluorescence Biosensing of Bicolor Silver Nanoclusters Hosted in a Switchable Deoxyribonucleic Acid Construct.

Ratiometric assays of label-free dual-signaling reporters with enzyme-free amplification are intriguing yet challenging. Herein, yellow- and red-silver nanocluster (yH-AgNC and rH-AgNC) acting as bicolor ratiometric emitters are guided to site-specifically cluster in two template signaling hairpins (yH and rH), respectively, and originally, both of them are almost non-fluorescent. The predesigned complement tethered in yH is recognizable to a DNA trigger (TOC) related to SARS-CoV-2. With the help of an enhancer strand (G15E) tethering G-rich bases (G15) and a linker strand (LS), a switchable DNA construct is assembled via their complementary hybridizing with yH and rH, in which the harbored yH-AgNC close to G15 is lighted-up. Upon introducing TOC, its affinity ligating with yH is further implemented to unfold rH and induce the DNA construct switching into closed conformation, causing TOC-repeatable recycling amplification through competitive strand displacement. Consequently, the harbored rH-AgNC is also placed adjacent to G15 for turning on its red fluorescence, while the yH-AgNC is retainable. As demonstrated, the intensity ratio dependent on varying TOC is reliable with high sensitivity down to 0.27 pM. By lighting-up dual-cluster emitters using one G15 enhancer, it would be promising to exploit a simpler ratiometric biosensing format for bioassays or clinical theranostics.

Serum 8-Hydroxy-2'-deoxyguanosine Predicts Severity and Prognosis of Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

BACKGROUND: Oxidative stress is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is recognized as a biomarker of oxidative stress and is implicated in several pulmonary diseases. Nonetheless, the role of 8-OHdG remains unclear in COPD patients. This research aimed to evaluate the correlations between serum 8-OHdG on admission and the severity and prognosis of hospitalized COPD patients with acute exacerbation. METHODS: A total of 150 COPD hospitalized patients and 150 healthy individuals were recruited. Serum 8-OHdG was measured by ELISA and the length of hospital stay was calculated. The number of acute exacerbations of COPD was tracked within 1 year after this hospitalization. RESULTS: The levels of serum 8-OHdG were elevated in COPD patients compared with the control group. Serum 8-OHdG was gradually elevated with decreased pulmonary function in COPD patients. Furthermore, Pearson linear association found that the levels of serum 8-OHdG were inversely correlated with pulmonary function and positively correlated with inflammatory cytokines in COPD patients. In addition, logistic regression analysis revealed that serum 8-OHdG elevation was a risk factor for pulmonary function decline in COPD patients. The length of hospital stay was tracked at this time. Higher serum 8-OHdG on admission increased the length of hospital stay among COPD patients. CONCLUSION: Serum 8-OHdG on admission is positively correlated with the severity and adverse prognosis among COPD patients, suggesting that 8-OHdG may be involved in the pathogenesis of COPD. Serum 8-OHdG may be a biomarker to predict the progression of COPD.

Arsenic induces ferroptosis and acute lung injury through mtROS-mediated mitochondria-associated endoplasmic reticulum membrane dysfunction.

The goal of this study was to analyze whether mitochondria-associated endoplasmic reticulum membrane (MAMs) dysfunction mediated arsenic (As)-evoked pulmonary ferroptosis and acute lung injury (ALI). As exposure led to alveolar structure damage, inflammatory cell infiltration and pulmonary function decline in mice. Ferritin, the marker of iron overload, was increased, GPX4, the index of lipid peroxidation, was decreased in As-exposed lungs and pulmonary epithelial cells (MLE-12). Pretreatment with ferrostatin-1 (Fer-1), the inhibitor of ferroptosis, alleviated As-evoked ALI. In addition, As-induced non-heme iron deposition was inhibited in Fer-1 pretreated-mice. Moreover, As-triggered mitochondria damage and ferroptosis were mitigated in Fer-1 pretreated-MLE-12 cells. Mechanistically, PERK phosphorylation and mitofusin-2 (Mfn-2) reduction was observed in As-exposed MLE-12 cells and mice lungs. Additionally, the interaction between PERK and Mfn-2 was downregulated and MAMs dysfunction was observed in As-exposed MLE-12 cells. Intriguingly, PERK inhibitor and Mfn-2-overexpression all mitigated As-induced ferroptosis in MLE-12 cells. Additionally, CLPP and mtHSP70, the markers of mitochondrial stress, were upregulated, mitochondrial ROS (mtROS) was elevated, mitochondrial membrane potential (MMP) and ATP were decreased in As-exposed MLE-12 cells. Mitoquinone mesylate (MitoQ), a novel mitochondrial-targeted antioxidant, alleviated As-induced excess mtROS, mitochondrial stress, MAMs dysfunction in pulmonary epithelial cells. Similarly, in vivo experiments indicated that MitoQ pretreatment countered As-induced pulmonary ferroptosis and ALI. These data indicated that mtROS-initiated MAMs dysfunction is, at least partially, implicated in As-evoked ferroptosis and ALI.

Serum interleukin-17 predicts severity and prognosis in patients with community acquired pneumonia: a prospective cohort study.

BACKGROUND: Some studies previously demonstrated that interleukin-17 (IL-17) involves in pulmonary diseases progression. Nevertheless, the role of IL-17 in community-acquired pneumonia (CAP) remains unknown. This study aims to examine the correlations between serum IL-17 with the severity and prognosis in CAP patients through a prospective cohort study. METHODS: All 239 CAP patients were recruited. Serum IL-17 was detected by enzyme-linked immunosorbent assay (ELISA). The CAP severity was evaluated through CAP severity scores, including CURB-65, CRB-65, PSI, SMART-COP, CURXO and APACHE II. RESULTS: Serum IL-17 was gradually increased consistent with the severity of CAP. Correlative analysis suggested that serum IL-17 was associated with clinical physiologic indicators among CAP patients. Logistic regression indicated that serum IL-17 was positively related to CAP severity scores. Additionally, the prognostic outcomes were tracked among CAP patients. The levels of IL-17 on admission were significantly increased in CAP patients with ICU admission, mechanical ventilation, vasoactive agent, death and longer hospitalization days. Logistic regression analyses revealed serum higher IL-17 on admission elevated the risks of vasoactive agent usage and longer hospital stays in CAP patients. The cut-off concentrations of serum IL-17 for death, ICU admission, mechanical ventilation and ≥ 14 hospital stays were 86.80 ng/mL, 84.92 ng/mL, 84.92 ng/mL and 60.29 ng/mL respectively. CONCLUSIONS: Serum IL-17 on admission is positively associated with the severity and poor prognosis among CAP patients, revealing that IL-17 may implicate in the pathological process of CAP. Therefore, serum IL-17 may become an effective biomarker for diagnosis, prognosis and therapy for CAP patients.

Copper-Catalyzed Remote Asymmetric Yne-Allylic Substitution of Yne-Allylic Esters with Anthrones.

Anthrones are key structural motifs in many natural products and pharmaceutical chemicals. However, due to its unique tricyclic aromatic structure, the synthetic space for the development of chiral anthrone derivatives is largely limited. By utilizing the potential of the copper-catalyzed remote asymmetric yne-allylic substitution reaction, we describe the first example of copper-catalyzed highly regio- and enantioselective remote yne-allylic substitution on various yne-allylic esters with anthrones under a mild reaction condition, which afforded a range of enantioenriched 1,3-enynes with exhibiting broad functional group tolerance across 51 examples.

Disturbance of fetal growth by azithromycin through induction of ER stress in the placenta.

AIM: Azithromycin (AZM) is widely used to treat mycoplasma infection in pregnancy. However, there is no adequate evaluation of its side effect on the placenta. Here, by using human placental syncytiotrophoblasts and a mouse model, we investigated whether AZM use in pregnancy might adversely affect placental function and pregnancy outcome. RESULTS: Transcriptomic analysis of AZM-treated human placental syncytiotrophoblasts showed increased expression of ER stress-related genes and decreased expression of genes for hormone production and growth factor processing. Verification studies showed that AZM increased the abundance of ER stress mediators (phosphorylated eIF2α, ATF4 and CHOP), and decreased the abundance of enzymes involved in progesterone and estradiol synthesis (STS, CYP11A1 and CYP19A1) and IGFBP cleavage (PAPPA and ADAM12) in human placental syncytiotrophoblasts. Inhibition of ER stress blocked AZM-induced decreases in the expression of CYP19A1, CYP11A1, PAPPA and ADAM12, suggesting that the inhibition of AZM on those genes' expression was secondary to AZM-induced ER stress. Further mechanism study showed that increased ATF4 in ER stress might repressively interact with C/EBPα to suppresstheexpression ofthose genes including CEBPAitself. Mouse studies showed that AZM administration decreased fetal weights along with increased ER stress mediators and decreased levels of insulin-like growth factor, estrogen and progesterone in the maternal blood, which could be alleviated by inhibition of ER stress. INNOVATION AND CONCLUSION: These findings firstly support AZM, often used during pregnancy, may affect fetal growth by inhibiting crucial enzymes for estrogen and progesterone synthesis and disrupting crucial proteases for IGFBP cleavage via inducing ER stress in placental syncytiotrophoblasts.

Benzo[a]pyrene evokes epithelial-mesenchymal transition and pulmonary fibrosis through AhR-mediated Nrf2-p62 signaling.

Benzo[a]pyrene (BaP) and its metabolic end product benzo(a)pyren-7,8-dihydrodiol-9,10-epoxide (BPDE), are known toxic environmental pollutants. This study aimed to analyze whether sub-chronic BPDE exposure initiated pulmonary fibrosis and the potential mechanisms. In this work, male C57BL6/J mice were exposed to BPDE by dynamic inhalation exposure for 8 weeks. Our results indicated that sub-chronic BPDE exposure evoked pulmonary fibrosis and epithelial-mesenchymal transition (EMT) in mice. Both in vivo and in vitro, BPDE exposure promoted nuclear translocation of Snail. Further experiments indicated that nuclear factor erythroid 2-related factor 2 (Nrf2) and p62 were upregulated in BPDE-exposed alveolar epithelial cells. Moreover, Nrf2 siRNA transfection evidently attenuated BPDE-induced p62 upregulation. Besides, p62 shRNA inhibited BPDE-incurred Snail nuclear translocation and EMT. Mechanically, BPDE facilitated physical interaction between p62 and Snail in the nucleus, then repressed Snail protein degradation by p62-dependent autophagy-lysosome pathway, and finally upregulated transcriptional activity of Snail. Additionally, aryl hydrocarbon receptor (AhR) was activated in BPDE-treated alveolar epithelial cells. Dual-luciferase assay indicated activating AhR could bind to Nrf2 gene promoter. Moreover, pretreatment with CH223191 or α-naphthoflavone (α-NF), AhR antagonists, inhibited BPDE-activated Nrf2-p62 signaling, and alleviated BPDE-induced EMT and pulmonary fibrosis in mice. Taken together, AhR-mediated Nrf2-p62 signaling contributes to BaP-induced EMT and pulmonary fibrosis.

ALKBH5 SUMOylation-mediated FBXW7 m6A modification regulates alveolar cells senescence during 1-nitropyrene-induced pulmonary fibrosis.

Our previous study revealed that 1-nitropyrene (1-NP) exposure evoked pulmonary fibrosis in mice. However, the exact mechanism remained elusive. We found that 1-NP induced telomere damage and cellular senescence in mice lungs, and two alveolar epithelial cells lines. 1-NP downregulated telomere repeat binding factor 2 (TRF2), and upregulated FBXW7. Mechanistically, 1-NP-caused TRF2 ubiquitination and proteasomal degradation depended on E3 ubiquitin ligase activity of FBXW7. Moreover, 1-NP upregulated FBXW7 m6A modification via an ALKBH5-YTHDF1-dependent manner. Further analysis suggested 1-NP promoted ALKBH5 SUMOylation and subsequent proteasomal degradation. Additionally, 1-NP evoked mitochondrial reactive oxygen species (mtROS) overproduction. Mito-TEMPO, a mitochondrial-targeted antioxidant, mitigated 1-NP-caused mtROS overproduction, ALKBH5 SUMOylation, FBXW7 m6A modification, TRF2 degradation, cellular senescence, and pulmonary fibrosis. Taken together, mtROS-initiated ALKBH5 SUMOylation and subsequent FBXW7 m6A modification is indispensable for TRF2 degradation and cellular senescence in alveolar epithelial cells during 1-NP-induced pulmonary fibrosis. Our study provides target intervention measures towards 1-NP-evoked pulmonary fibrosis.

Epidermal growth factor: Expression in goat endometrial epithelia during early pregnancy and regulation by interferon tau and FOXO1.

In ruminants, establishment and maintenance of pregnancy depends upon a well-coordinated interaction between the conceptus and the maternal endometrium. Epidermal growth factor (EGF) is important for embryo implantation and pregnancy establishment. However, the regulatory mechanisms of EGF expression remain unclear. FOXO1, a member of the Forkhead box O (FOXO) subfamily of transcription factors, is currently accepted as a novel endometrial receptivity marker for humans and mice owing to its timely and specific expression at the window of implantation. In this study, we examined the spatiotemporal expression profile of EGF in goat uterus during early pregnancy (Day 0 to Day 50 of pregnancy) and verified that EGF expression was regulated by FOXO1 and interferon tau (IFNT). Our results showed that EGF was highly expressed in the luminal epithelium (LE) and the glandular epithelium (GE) during conceptus adhesion (Day 16 to Day 25 of pregnancy). After implantation, EGF protein signals were continuously detected in the endometrial epithelia and appeared in the conceptus trophectoderm. Furthermore, EGF expression could be up-regulated by IFNT in goat uterus and primary endometrial epithelium cells (EECs). The luciferase assay results showed that FOXO1 could promote EGF transcription by binding to its promoter. And FOXO1 positively regulates EGF expression in goat EECs. These findings contribute to better understanding the role and regulation mechanisms of EGF during ruminant early pregnancy.

ADAMTS4 is a crucial proteolytic enzyme for versican cleavage in the amnion at parturition.

Hyalectan cleavage may play an important role in extracellular matrix remodeling. However, the proteolytic enzyme responsible for hyalectan degradation for fetal membrane rupture at parturition remains unknown. Here, we reveal that versican (VCAN) is the major hyalectan in the amnion, where its cleavage increases at parturition with spontaneous rupture of membrane. We further reveal that ADAMTS4 is a crucial proteolytic enzyme for VCAN cleavage in the amnion. Inflammatory factors may enhance VCAN cleavage by inducing ADAMTS4 expression and inhibiting ADAMTS4 endocytosis in amnion fibroblasts. In turn, versikine, the VCAN cleavage product, induces inflammatory factors in amnion fibroblasts, thereby forming a feedforward loop between inflammation and VCAN degradation. Mouse studies show that intra-amniotic injection of ADAMTS4 induces preterm birth along with increased VCAN degradation and proinflammatory factors abundance in the fetal membranes. Conclusively, there is enhanced VCAN cleavage by ADAMTS4 in the amnion at parturition, which can be reenforced by inflammation.

Regulation of depressive-like behaviours by palmitoylation: Role of AKAP150 in the basolateral amygdala.

BACKGROUND AND PURPOSE: Protein palmitoylation is involved in learning and memory, and in emotional disorders. Yet, the underlying mechanisms in these processes remain unclear. Herein, we describe that A-kinase anchoring protein 150 (AKAP150) is essential and sufficient for depressive-like behaviours in mice via a palmitoylation-dependent mechanism. EXPERIMENTAL APPROACH: Depressive-like behaviours in mice were induced by chronic restraint stress (CRS) and chronic unpredictable mild stress (CUMS). Palmitoylated proteins in the basolateral amygdala (BLA) were assessed by an acyl-biotin exchange assay. Genetic and pharmacological approaches were used to investigate the role of the DHHC2-mediated AKAP150 palmitoylation signalling pathway in depressive-like behaviours. Electrophysiological recording, western blotting and co-immunoprecipitation were performed to define the mechanistic pathway. KEY RESULTS: Chronic stress successfully induced depressive-like behaviours in mice and enhanced AKAP150 palmitoylation in the BLA, and a palmitoylation inhibitor was enough to reverse these changes. Blocking the AKAP150-PKA interaction with the peptide Ht-31 abolished the CRS-induced AKAP150 palmitoylation signalling pathway. DHHC2 expression and palmitoylation levels were both increased after chronic stress. DHHC2 knockdown prevented CRS-induced depressive-like behaviours, as well as attenuating AKAP150 signalling and synaptic transmission in the BLA in CRS-treated mice. CONCLUSION AND IMPLICATIONS: These results delineate that DHHC2 modulates chronic stress-induced depressive-like behaviours and synaptic transmission in the BLA via the AKAP150 palmitoylation signalling pathway, and this pathway may be considered as a promising novel therapeutic target for major depressive disorder.

Reduction of lymphocyte count at early stage elevates severity and death risk of COVID-19 patients: a hospital-based case-cohort study.

Introduction: Several reports have noted that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induced lymphopenia in coronavirus disease 2019 (COVID-19) patients. However, the clinical significance of lymphopenia remains unclear. The objective of this study was to analyze the association between lymphopenia at an early stage and the prognosis of COVID-19 patients. Material and methods: All 192 hospitalized patients with COVID-19 were enrolled. Demographic data and clinical characteristics were collected and patient's prognosis was followed up. Results: On admission, 84 (43.8%) patients suffered from lymphopenia among COVID-19 patients. The count and percentage of lymphocytes on admission were lower among patients over 70 years old than those of younger patients. Multivariate logistic regression revealed that older age was a risk factor of lymphopenia. Of interest, chest CT score, a key marker of lung injury, was increased among COVID-19 patients with lymphopenia. By contrast, PaCO2, SpO2 and oxygenation index, several respiratory function markers, were decreased in COVID-19 patients with lymphopenia. Moreover, total bilirubin (TBIL) and direct bilirubin (DBIL), two markers of hepatic injury, creatinine and urea nitrogen, two indices of renal function, and creatine kinase, AST and LDH, three myocardial enzymes, were elevated in COVID-19 patients with lymphopenia. Among 84 COVID-19 patients with lymphopenia, 32.1% died. The fatality rate was obviously higher in COVID-19 patients with lymphopenia. Conclusions: Older COVID-19 patients are more susceptible to lymphopenia. Multiple organ injuries were more serious in COVID-19 patients with lymphopenia. Lymphopenia at an early stage aggravates the severity and elevates the death risk of COVID-19 patients.