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1.
Front Neurosci ; 18: 1362899, 2024.
Article in English | MEDLINE | ID: mdl-38784088

ABSTRACT

Central 5-hydroxytryptaminergic dorsal raphe nucleus (5-HTDRN)-bed nucleus of stria terminalis (BNST) neural circuit dysfunction is one of the important neurobiological basis of anxiety and fear disorders. Under stress, 5-hydroxytryptamine (5-HT) neurons act on BNST receptors to attenuate anxiety and fear responses or enhance anxiety and fear. In BNST, corticotropin releasing factor neurons play a role in regulating emotions by reversely regulating excitatory or inhibitory 5-HT neurons. The composition of 5-HTDRN-BNST neural circuit, the pathological changes of 5-HTDRN-BNST neural circuit function damage under stress, and the effects of 5-HTDRN-BNST neural circuit on anxiety disorder, panic disorder and post-traumatic stress disorder were analyzed and are summarized in this paper. The characteristics of functional changes of the neural circuit and its effects on brain functional activities provide a basis and ideas for the treatment of anxiety and fear disorders through the regulation of 5-HTDRN-BNST neural circuit, and they also provide a new perspective for understanding the pathological mechanism of such diseases.

2.
Dev Cell ; 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38569547

ABSTRACT

The ability of cells to perceive and respond to mechanical cues is essential for numerous biological activities. Emerging evidence indicates important contributions of organelles to cellular mechanosensitivity and mechanotransduction. However, whether and how the endoplasmic reticulum (ER) senses and reacts to mechanical forces remains elusive. To fill the knowledge gap, after developing a light-inducible ER-specific mechanostimulator (LIMER), we identify that mechanostimulation of ER elicits a transient, rapid efflux of Ca2+ from ER in monkey kidney COS-7 cells, which is dependent on the cation channels transient receptor potential cation channel, subfamily V, member 1 (TRPV1) and polycystin-2 (PKD2) in an additive manner. This ER Ca2+ release can be repeatedly stimulated and tuned by varying the intensity and duration of force application. Moreover, ER-specific mechanostimulation inhibits ER-to-Golgi trafficking. Sustained mechanostimuli increase the levels of binding-immunoglobulin protein (BiP) expression and phosphorylated eIF2α, two markers for ER stress. Our results provide direct evidence for ER mechanosensitivity and tight mechanoregulation of ER functions, placing ER as an important player on the intricate map of cellular mechanotransduction.

3.
Microsyst Nanoeng ; 10: 48, 2024.
Article in English | MEDLINE | ID: mdl-38590817

ABSTRACT

Double-sided microlens arrays (DSMLAs) include combinations of two single-sided MLAs to overcome positioning errors and greatly improve light transmissivity compared to other types of lenses. Precision glass molding (PGM) is used to fabricate DSMLAs, but controlling alignment errors during this process is challenging. In this paper, a mold assembly was manufactured with a novel combination of materials to improve the alignment accuracy of mold cores during PGM by using the nonlinear thermal expansion characteristics of the various materials to improve the DSMLA alignment accuracy. By establishing a mathematical model of the DSMLA alignment error and a thermal expansion model of the mold-sleeve pair, the relationship between the maximum alignment error of the DSMLA and the mold-sleeve gap was determined. This research provides a method to optimize the mold-sleeve gap and minimize the alignment error of the DSMLA. The measured DSMLA alignment error was 10.56 µm, which is similar to the predicted maximum alignment error. Optical measurements showed that the uniformity of the homogenized beam spot was 97.81%, and the effective homogeneous area accounted for 91.66% of the total area. This proposed method provides a novel strategy to improve the performance of DSMLAs.

4.
Physiol Behav ; 278: 114481, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38369217

ABSTRACT

Willingness to pay (WTP) pervades every marketplace transaction, therefore, understanding how the brain makes bidding decisions is essential in consumer neuroscience. Although some neuroimaging studies have investigated the neural networks of WTP, systematic understanding remains limited. This study identified reliable neural networks activated by the WTP across different reward types and assessed common and distinct neural networks for different reward types (food and other) bids. We conducted an activation likelihood estimation (ALE) meta-analysis on WTP across different reward types (25 studies; 254 foci; 705 participants), and to compared neural representations of WTP for food reward (22 studies; 232 foci; 628 participants) and other rewards (7 studies, 61 foci; 177 participants). The ALE results revealed that the brain centers of WTP for different rewards mainly consist of the bilateral inferior frontal gyrus (IFG), bilateral insula, bilateral anterior cingulate cortex (ACC), along with the left caudate. This suggests that neural networks encoding WTP for different rewards consist of brain regions associated with reward processing, cost-benefit calculations, and goal-directed action activities. In addition, consistent activation of the bilateral IFG and bilateral insula for food but no other rewards bids suggest their involvement in the neural network of appetite. WTP for food and other rewards commonly activated ACC, suggesting a common region encoding bids for different rewards. Our findings provide novel insights into neural networks associated with WTP for food and other rewards bids and the mechanisms underlying WTP across different reward types.


Subject(s)
Brain , Magnetic Resonance Imaging , Humans , Brain/physiology , Prefrontal Cortex/physiology , Neuroimaging , Head , Reward , Brain Mapping
5.
Zhen Ci Yan Jiu ; 49(2): 135-144, 2024 Feb 25.
Article in English, Chinese | MEDLINE | ID: mdl-38413034

ABSTRACT

OBJECTIVES: To observe the effect of electroacupuncture (EA) of scalp acupoint (Dingnieqian-xiexian, MS6) on expression of retinoid-related orphan receptor γT (ROR γ t), interleukin (IL)-17A, IL-10, transfor-ming growth factor-ß1 (TGF-ß1), IL-6, IL-21, and IL-17A+ Thelper cells(Th) 17 and forkhead transcription factor P3 (FOXP3)+ regulatory T cells (Treg) differentiation of ischemic cortex in ischemic stroke rats, so as to explore its molecular mechanisms underlying relief of inflammatory injury of ischemic stroke. METHODS: A total of 120 male SD rats were randomly assigned to sham operation, model, EA, inhibitor, agonist and EA+agonist groups, with 15 rats in each group. The ischemic stroke model was established by occlusion of the left middle cerebral artery according to Longa's methods. For rats of the EA group and EA+agonist group, EA (2 Hz/100 Hz, 1 mA) was applied to bilateral MS6 for 30 min, once daily for 7 days. Rats of the inhibitor group received intraperitoneal injection of solution of SR1001 (RORγt inhibitor) (2.5 mg/mL, 10 mg/kg), once daily for 7 days. Rats of the agonist and EA+agonist groups received intraperitoneal injection of solution of SR1078 (RORγt agonist) (5 mg/mL, 5 mg/kg) before EA, once daily for 7 days. Rats of the sham operation and model groups were grabbed and fixed in the same way with the other groups. The Zea-longa's score, modified neurological severity score (mNSS) and the neurobehavioral score were assessed before and after the intervention. At the end of experiments, the ischemic cortex tissue was collected. The 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining was used to detect the volume of cerebral infarction. The expression of RORγt mRNA was detected by real-time quantitative PCR;the protein expression levels of RORγt, IL-17A, IL-10 and TGF-ß1 were detected by Western blot;the immunoactivity of IL-6 and IL-21 were detected by immunohistochemistry;the fluorescence areas of IL-17A+Th17 and FOXP3+Treg cells were measured by immunofluorescence and their ratio was calculated in the tissue of ischemic cortex. RESULTS: Relevant to the sham operation group, the model group had a significant increase in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01), and an obvious decrease in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.01). In contrast to the model group, both EA and inhibitor groups had a significant decrease in the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg (P<0.01, P<0.05), and a marked increase in the expression levels of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity (P<0.05, P<0.01), while the above indicators of the agonist group were all reversed (P<0.01, P<0.05). Comparison between the agonist and EA+agonist groups showed that the Zea-Longa's score, mNSS score, neurobehavioral score, cerebral infarct volume, expression levels of RORγt mRNA and protein, IL-17A protein, IL-6 and IL-21 immunoactivity, IL-17A+Th17 immunofluorescence intensity, and the ratio of IL-17A+Th17/FOXP3+Treg were significantly lower (P<0.01, P<0.05), and the expression of TGF-ß1 and IL-10 proteins and FOXP3+Treg immunofluorescence intensity were obviously higher (P<0.01, P<0.05) in the EA+agonist group than in the agonist group, suggesting that EA intervention can effectively weaken the effects of RORγt agonist. CONCLUSIONS: EA of scalp acupoint MS6 can effectively improve the neurological function, behavior reaction and reduce cerebral infarct volume in ischemic stroke rats, which may be associated with its functions in down-regulating the expression of RORγt and promoting the balance of IL-17A+Th17/FOXP3+Treg to alleviate inflammatory injury after ischemic stroke.


Subject(s)
Brain Ischemia , Electroacupuncture , Ischemic Stroke , Rats , Male , Animals , Rats, Sprague-Dawley , Brain Ischemia/genetics , Brain Ischemia/therapy , Interleukin-10 , Nuclear Receptor Subfamily 1, Group F, Member 3/genetics , Interleukin-17/genetics , Interleukin-6 , Acupuncture Points , Scalp , T-Lymphocytes, Regulatory , Transforming Growth Factor beta1 , Cerebral Infarction , Forkhead Transcription Factors , RNA, Messenger
6.
Acta Pharmacol Sin ; 45(5): 975-987, 2024 May.
Article in English | MEDLINE | ID: mdl-38279042

ABSTRACT

Endothelium-dependent contraction (EDC) exists in blood vessels of normotensive animals, but is exaggerated in hypertension. An early signal in EDC is cytosolic Ca2+ rise in endothelial cells. In this study we investigated the functional role of Orai1, a major endothelial cell Ca2+ entry channel, in EDC. Hypertension model was established in WT mice by intake of L-NNA in the drinking water (0.5 g/L) for 4 weeks or osmotic pump delivery of Ang II (1.5 mg·kg-1·d-1) for 2 weeks. In TRPC5 KO mice, the concentration of L-NNA and Ang II were increased to 1 g/L or 2 mg·kg-1·d-1, respectively. Arterial segments were prepared from carotid arteries and aortas, and EDC was elicited by acetylcholine in the presence of Nω-nitro-L-arginine methyl ester. We showed that low concentration of acetylcholine (3-30 nM) initiated relaxation in phenylephrine-precontracted carotid arteries of both normotensive and hypertensive mice, while high concentration of acetylcholine (0.1-2 µM) induced contraction. Application of selective Orai1 inhibitors AnCoA4 (100 µM) or YM58483 (400 nM) had no effect on ACh-induced relaxation but markedly reduced acetylcholine-induced EDC. We found that EDC was increased in hypertensive mice compared with that of normotensive mice, which was associated with increased Orai1 expression in endothelial cells of hypertensive mice. Compared to TRPC5 and TRPV4, which were also involved in EDC, endothelial cell Orai1 had relatively greater contribution to EDC than either TRPC5 or TRPV4 alone. We identified COX-2, followed by PGF2α, PGD2 and PGE2 as the downstream signals of Orai1/TRPC5/TRPV4. In conclusion, Orai1 coordinates together with TRPC5 and TRPV4 in endothelial cells to regulate EDC responses. This study demonstrates a novel function of Orai1 in EDC in both normotensive and hypertensive mice, thus providing a general scheme about the control of EDC by Ca2+-permeable channels.


Subject(s)
Carotid Arteries , Endothelial Cells , Endothelium, Vascular , Hypertension , Mice, Inbred C57BL , Mice, Knockout , ORAI1 Protein , TRPC Cation Channels , Animals , ORAI1 Protein/metabolism , Hypertension/metabolism , Hypertension/physiopathology , Male , Mice , Endothelial Cells/metabolism , Endothelial Cells/drug effects , Carotid Arteries/drug effects , Carotid Arteries/metabolism , TRPC Cation Channels/metabolism , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Acetylcholine/pharmacology , Angiotensin II/pharmacology , Vasoconstriction/drug effects , TRPV Cation Channels/metabolism
7.
Int J Mol Sci ; 24(18)2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37762235

ABSTRACT

COVID-19 pandemic, caused by the SARS-CoV-2 virus, is still affecting the entire world via the rapid emergence of new contagious variants. Vaccination remains the most effective prevention strategy for viral infection, yet not all countries have sufficient access to vaccines due to limitations in manufacturing and transportation. Thus, there is an urgent need to develop an easy-to-use, safe, and low-cost vaccination approach. Genetically modified microorganisms, especially probiotics, are now commonly recognized as attractive vehicles for delivering bioactive molecules via oral and mucosal routes. In this study, Lactobacillus casei has been selected as the oral vaccine candidate based on its' natural immunoadjuvant properties and the ability to resist acidic gastric environment, to express antigens of SARS-CoV-2 Omicron variant B.1.1.529 with B-cell and T-cell epitopes. This newly developed vaccine, OMGVac, was shown to elicit a robust IgG systemic immune response against the spike protein of Omicron variant B.1.1.529 in Golden Syrian hamsters. No adverse effects were found throughout this study, and the overall safety was evaluated in terms of physiological and histopathological examinations of different organs harvested. In addition, this study illustrated the use of the recombinant probiotic as a live delivery vector in the initiation of systemic immunity, which shed light on the future development of next-generation vaccines to combat emerging infectious diseases.


Subject(s)
COVID-19 , Vaccines , Animals , Cricetinae , Humans , SARS-CoV-2/genetics , COVID-19 Vaccines , Pandemics , COVID-19/prevention & control , Mesocricetus
8.
Angew Chem Int Ed Engl ; 62(46): e202312692, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37747050

ABSTRACT

The precisely modulated synthesis of programmable light-emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene-based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation-induced electrochemiluminescence (PI-AIECL) systems. The best-performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2'-bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six-fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL-based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high-performance aggregation-induced electrochemiluminescence emitters.

10.
Biomark Res ; 11(1): 74, 2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37553583

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a dismal prognosis, and despite significant advances in our understanding of its genetic drivers, like KRAS, TP53, CDKN2A, and SMAD4, effective therapies remain limited. Here, we identified a new therapeutic target GRIN2D and then explored its functions and mechanisms in PDAC progression. METHODS: We performed a genome-wide RNAi screen in a PDAC xenograft model and identified GRIN2D, which encodes the GluN2D subunit of N-methyl-D-aspartate receptors (NMDARs), as a potential oncogene. Western blot, immunohistochemistry, and analysis on Gene Expression Omnibus were used for detecting the expression of GRIN2D in PDAC. Cellular experiments were conducted for exploring the functions of GRIN2D in vitro while subcutaneous and orthotopic injections were used in in vivo study. To clarify the mechanism, we used RNA sequencing and cellular experiments to identify the related signaling pathway. Cellular assays, RT-qPCR, and western blot helped identify the impacts of the NMDAR antagonist memantine. RESULTS: We demonstrated that GRIN2D was highly expressed in PDAC cells, and further promoted oncogenic functions. Mechanistically, transcriptome profiling identified GRIN2D-regulated genes in PDAC cells. We found that GRIN2D promoted PDAC progression by activating the p38 MAPK signaling pathway and transcription factor CREB, which in turn promoted the expression of HMGA2 and IL20RB. The upregulated GRIN2D could effectively promote tumor growth and liver metastasis in PDAC. We also investigated the therapeutic potential of NMDAR antagonism in PDAC and found that memantine reduced the expression of GRIN2D and inhibited PDAC progression. CONCLUSION: Our results suggested that NMDA receptor GRIN2D plays important oncogenic roles in PDAC and represents a novel therapeutic target.

11.
Mycotoxin Res ; 39(4): 347-364, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37400696

ABSTRACT

Breast cancer has replaced lung cancer to be the leading cancer in the world. Currently, chemotherapy is still the major method for breast cancer therapy, but its overall effect remains unsatisfactory. Fusaric acid (FSA), a mycotoxin derived from fusarium species, has shown potency against the proliferation of several types of cancer cells, but its effect on breast cancer cells has not been examined. Therefore, we explored the possible effect of FSA on the proliferation of MCF-7 human breast cancer cells and uncovered the underlying mechanism in the present study. Our results showed that FSA has a strong anti-proliferative effect on MCF-7 cells through inducing ROS production, apoptosis and arresting cell cycle at G2/M transition phase. Additionally, FSA triggers endoplasmic reticulum (ER) stress in the cells. Notably, the cell cycle arrest and apoptosis inducing effect of FSA can be attenuated by ER stress inhibitor, tauroursodeoxycholic acid. Our study provide evidence that FSA is a potent proliferation inhibition and apoptosis inducing agent against human breast cancer cells, and the possible mechanism involves the activation of ER stress signaling pathways. Our study may highlight that FSA is promising for the future in vivo study and development of potential agent for breast cancer therapy.


Subject(s)
Breast Neoplasms , Fusaric Acid , Humans , Female , MCF-7 Cells , Fusaric Acid/pharmacology , Fusaric Acid/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Apoptosis , Cell Proliferation , Endoplasmic Reticulum Stress , Cell Line, Tumor
12.
Stem Cell Res Ther ; 14(1): 158, 2023 06 07.
Article in English | MEDLINE | ID: mdl-37287081

ABSTRACT

BACKGROUND: Cardiomyocytes derived from pluripotent stem cells (PSC-CMs) have been widely accepted as a promising cell source for cardiac drug screening and heart regeneration therapies. However, unlike adult cardiomyocytes, the underdeveloped structure, the immature electrophysiological properties and metabolic phenotype of PSC-CMs limit their application. This project aimed to study the role of the transient receptor potential ankyrin 1 (TRPA1) channel in regulating the maturation of embryonic stem cell-derived cardiomyocytes (ESC-CMs). METHODS: The activity and expression of TRPA1 in ESC-CMs were modulated by pharmacological or molecular approaches. Knockdown or overexpression of genes was done by infection of cells with adenoviral vectors carrying the gene of interest as a gene delivery tool. Immunostaining followed by confocal microscopy was used to reveal cellular structure such as sarcomere. Staining of mitochondria was performed by MitoTracker staining followed by confocal microscopy. Calcium imaging was performed by fluo-4 staining followed by confocal microscopy. Electrophysiological measurement was performed by whole-cell patch clamping. Gene expression was measured at mRNA level by qPCR and at protein level by Western blot. Oxygen consumption rates were measured by a Seahorse Analyzer. RESULTS: TRPA1 was found to positively regulate the maturation of CMs. TRPA1 knockdown caused nascent cell structure, impaired Ca2+ handling and electrophysiological properties, and reduced metabolic capacity in ESC-CMs. The immaturity of ESC-CMs induced by TRPA1 knockdown was accompanied by reduced mitochondrial biogenesis and fusion. Mechanistically, we found that peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), the key transcriptional coactivator related to mitochondrial biogenesis and metabolism, was downregulated by TRPA1 knockdown. Interestingly, overexpression of PGC-1α ameliorated the halted maturation induced by TRPA1 knockdown. Notably, phosphorylated p38 MAPK was upregulated, while MAPK phosphatase-1 (MKP-1), a calcium-sensitive MAPK inhibitor, was downregulated in TRPA1 knockdown cells, suggesting that TRPA1 may regulate the maturation of ESC-CMs through MKP-1-p38 MAPK-PGC-1α pathway. CONCLUSIONS: Taken together, our study reveals the novel function of TRPA1 in promoting the maturation of CMs. As multiple stimuli have been known to activate TRPA1, and TRPA1-specific activators are also available, this study provides a novel and straightforward strategy for improving the maturation of PSC-CMs by activating TRPA1. Since a major limitation for the successful application of PSC-CMs for research and medicine lies in their immature phenotypes, the present study takes a big step closer to the practical use of PSC-CMs.


Subject(s)
Myocytes, Cardiac , Organelle Biogenesis , Myocytes, Cardiac/metabolism , Calcium/metabolism , Embryonic Stem Cells/metabolism , Enzyme Inhibitors/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism , Cell Differentiation
13.
Cells ; 12(9)2023 04 26.
Article in English | MEDLINE | ID: mdl-37174651

ABSTRACT

It is well established that the accumulation of high levels of reactive oxygen species (ROS), due to excessive generation of ROS and/or impaired antioxidant capacity of cells, can result in oxidative stress and cause oxidative damage to cells and their functions [...].


Subject(s)
Antioxidants , Oxidative Stress , Reactive Oxygen Species , Antioxidants/metabolism , Signal Transduction
14.
Acta Pharmacol Sin ; 44(10): 1977-1988, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37217602

ABSTRACT

Atherosclerotic diseases remain the leading cause of adult mortality and impose heavy burdens on health systems globally. Our previous study found that disturbed flow enhanced YAP activity to provoke endothelial activation and atherosclerosis, and targeting YAP alleviated endothelial inflammation and atherogenesis. Therefore, we established a luciferase reporter assay-based drug screening platform to seek out new YAP inhibitors for anti-atherosclerotic treatment. By screening the FDA-approved drug library, we identified that an anti-psychotic drug thioridazine markedly suppressed YAP activity in human endothelial cells. Thioridazine inhibited disturbed flow-induced endothelial inflammatory response in vivo and in vitro. We verified that the anti-inflammatory effects of thioridazine were mediated by inhibition of YAP. Thioridazine regulated YAP activity via restraining RhoA. Moreover, administration of thioridazine attenuated partial carotid ligation- and western diet-induced atherosclerosis in two mouse models. Overall, this work opens up the possibility of repurposing thioridazine for intervention of atherosclerotic diseases. This study also shed light on the underlying mechanisms that thioridazine inhibited endothelial activation and atherogenesis via repression of RhoA-YAP axis. As a new YAP inhibitor, thioridazine might need further investigation and development for the treatment of atherosclerotic diseases in clinical practice.


Subject(s)
Atherosclerosis , Endothelial Cells , Thioridazine , Animals , Humans , Mice , Atherosclerosis/drug therapy , Atherosclerosis/prevention & control , Inflammation/etiology , rhoA GTP-Binding Protein/drug effects , Thioridazine/therapeutic use , YAP-Signaling Proteins/drug effects
15.
ChemSusChem ; 16(3): e202202104, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36478405

ABSTRACT

The development of a sustainable and simple catalytic system for N-formylation of N-heterocycles with methanol by direct coupling remains a challenge, owing to many competing side reactions, given the sensitivity of N-heterocycles to many catalytic oxidation or dehydrogenation systems. This work concerns the development of an in situ-generated CuI catalytic system for oxidative N-formylation of N-heterocycles with methanol that is based on the case study of a more typical 1,2,3,4-tetrahydroquinoline as substrate. Aside from N-heterocycles, some acyclic amines are also transformed into the corresponding N-formamides in moderate yields. Furthermore, a probable reaction mechanism and reaction pathway are proposed and extension of work based on some findings leads to a demonstration that the formed ⋅O2 - and ⋅OOH radicals in the catalytic system is related to the formation of undesired tar-like products.

16.
Nat Commun ; 13(1): 5728, 2022 09 29.
Article in English | MEDLINE | ID: mdl-36175399

ABSTRACT

F-actin dynamics is crucial for many fundamental properties of cancer cells, from cell-substrate adhesion to migration, invasion and metastasis. However, the regulatory mechanisms of actin dynamics are still incompletely understood. In this study, we demonstrate the function of a protein named TM9SF4 in regulating actin dynamics and controlling cancer cell motility and metastasis. We show that an N-terminal fragment (NTF) cleaved from TM9SF4 can directly bind to F-actin to induce actin oxidation at Cys374, consequently enhancing cofilin-mediated F-actin disassembly. Knockdown of TM9SF4 reduces cell migration and invasion in ovarian cancer cells A2780, SKOV3 and several high grade serous ovarian cancer lines (HGSOCs). In vivo, knockdown of TM9SF4 completely abolishes the tumor growth and metastasis in athymic nude mice. These data provide mechanistic insights into TM9SF4-mediated regulation of actin dynamics in ovarian cancer cells.


Subject(s)
Actins , Ovarian Neoplasms , Actin Depolymerizing Factors/genetics , Animals , Carcinoma, Ovarian Epithelial , Cell Line, Tumor , Female , Humans , Membrane Proteins , Mice , Mice, Nude , Ovarian Neoplasms/genetics
17.
Pflugers Arch ; 474(7): 665-680, 2022 07.
Article in English | MEDLINE | ID: mdl-35567642

ABSTRACT

Mammalian expression systems, particularly the human embryonic kidney (HEK-293) cells, combined with electrophysiological studies, have greatly benefited our understanding of the function, characteristic, and regulation of various ion channels. It was previously assumed that the existence of endogenous ion channels in native HEK-293 cells could be negligible. Still, more and more ion channels are gradually reported in native HEK-293 cells, which should draw our attention. In this regard, we summarize the different ion channels that are endogenously expressed in HEK-293 cells, including voltage-gated Na+ channels, Ca2+ channels, K+ channels, Cl- channels, nonselective cation channels, TRP channels, acid-sensitive ion channels, and Piezo channels, which may complicate the recording of the heterogeneously expressed ion channels to a certain degree. We noted that the expression patterns and channel profiles varied with different studies, which may be due to the distinct originality of the cells, cell culture conditions, passage numbers, and different recording protocols. Therefore, a better knowledge of endogenous ion channels may help minimize potential problems in characterizing heterologously expressed ion channels. Based on this, it is recommended that HEK-293 cells from unknown sources should be examined before transfection for the characterization of their functional profile, especially when the expression level of exogenous ion channels does not overwhelm the endogenous ion channels largely, or the current amplitude is not significantly higher than the native currents.


Subject(s)
Ion Channels , Sodium , Animals , HEK293 Cells , Humans , Ion Channels/metabolism , Kidney/metabolism , Mammals/metabolism , Patch-Clamp Techniques , Sodium/metabolism
18.
Cells ; 11(9)2022 04 22.
Article in English | MEDLINE | ID: mdl-35563730

ABSTRACT

Atherosclerosis is a chronic inflammatory arterial disease characterized by build-up of atheromatous plaque, which narrows the lumen of arteries. Hypercholesterolemia and excessive oxidative stress in arterial walls are among the main causative factors of atherosclerosis. Transient receptor potential channel M2 (TRPM2) is a Ca2+-permeable cation channel activated by oxidative stress. However, the role of TRPM2 in atherosclerosis in animal models is not well studied. In the present study, with the use of adeno-associated virus (AAV)-PCSK9 and TRPM2 knockout (TRPM2-/-) mice, we determined the role of TRPM2 in hypercholesterolemia-induced atherosclerosis. Our results demonstrated that TRPM2 knockout reduced atherosclerotic plaque area in analysis of En face Oil Red O staining of both whole aortas and aortic-root thin sections. Furthermore, TRPM2 knockout reduced the expression of CD68, α-SMA, and PCNA in the plaque region, suggesting a role of TRPM2 in promoting macrophage infiltration and smooth-muscle cell migration into the lesion area. Moreover, TRPM2 knockout reduced the expression of ICAM-1, MCP-1, and TNFα and decreased the ROS level in the plaque region, suggesting a role of TRPM2 in enhancing monocyte adhesion and promoting vascular inflammation. In bone-marrow-derived macrophages and primary cultured arterial endothelial cells, TRPM2 knockout reduced the production of inflammatory cytokines/factors and decreased ROS production. In addition, a TRPM2 antagonist N-(p-amylcinnamoyl) anthranilic acid (ACA) was able to inhibit atherosclerotic development in an ApoE-/- mouse model of atherosclerosis. Taken together, the findings of our study demonstrated that TRPM2 contributes to the progression of hypercholesterolemia-induced atherosclerosis. Mechanistically, TRPM2 channels may provide an essential link that can connect ROS to Ca2+ and inflammation, consequently promoting atherosclerotic progression.


Subject(s)
Atherosclerosis , Hypercholesterolemia , Plaque, Atherosclerotic , TRPM Cation Channels , Transient Receptor Potential Channels , Animals , Atherosclerosis/metabolism , Disease Models, Animal , Endothelial Cells/metabolism , Hypercholesterolemia/metabolism , Hypercholesterolemia/pathology , Inflammation/pathology , Mice , Plaque, Atherosclerotic/pathology , Proprotein Convertase 9/metabolism , Reactive Oxygen Species/metabolism , TRPM Cation Channels/genetics , TRPM Cation Channels/metabolism , Transient Receptor Potential Channels/metabolism
19.
Eur Radiol ; 32(9): 5930-5942, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35384460

ABSTRACT

OBJECTIVES: To develop and validate an optimal model based on the 1-mm-isotropic-3D contrast-enhanced StarVIBE MRI sequence combined with clinical risk factors for predicting survival in patients with esophageal squamous cell carcinoma (ESCC). METHODS: Patients with ESCC at our institution from 2015 to 2017 participated in this retrospective study based on prospectively acquired data, and were randomly assigned to training and validation groups at a ratio of 7:3. Random survival forest (RSF) and variable hunting methods were used to screen for radiomics features and LASSO-Cox regression analysis was used to build three models, including clinical only, radiomics only and combined clinical and radiomics models, which were evaluated by concordance index (CI) and calibration curve. Nomograms and decision curve analysis (DCA) were used to display intuitive prediction information. RESULTS: Seven radiomics features were selected from 434 patients, combined with clinical features that were statistically significant to construct the predictive models of disease-free survival (DFS) and overall survival (OS). The combined model showed the highest performance in both training and validation groups for predicting DFS ([CI], 0.714, 0.729) and OS ([CI], 0.730, 0.712). DCA showed that the net benefit of the combined model and of the clinical model is significantly greater than that of the radiomics model alone at different threshold probabilities. CONCLUSIONS: We demonstrated that a combined predictive model based on MR Rad-S and clinical risk factors had better predictive efficacy than the radiomics models alone for patients with ESCC. KEY POINTS: • Magnetic resonance-based radiomics features combined with clinical risk factors can predict survival in patients with ESCC. • The radiomics nomogram can be used clinically to predict patient recurrence, DFS, and OS. • Magnetic resonance imaging is highly reproducible in visualizing lesions and contouring the whole tumor.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Disease-Free Survival , Esophageal Neoplasms/diagnostic imaging , Esophageal Squamous Cell Carcinoma/diagnostic imaging , Humans , Magnetic Resonance Imaging/methods , Nomograms , Retrospective Studies
20.
Cell Mol Gastroenterol Hepatol ; 14(2): 245-270, 2022.
Article in English | MEDLINE | ID: mdl-35398597

ABSTRACT

BACKGROUND & AIMS: Inflammatory bowel disease (IBD) is a major intestinal disease. Excessive inflammation and increased endoplasmic reticulum (ER) stress are the key events in the development of IBD. Search of a genome-wide association study database identified a remarkable correlation between a TM9SF4 single-nucleotide polymorphism and IBD. Here, we aimed to resolve its underlying mechanism. METHODS: The role of TM9SF4 was determined with experimental mouse models of IBD. ER stress cascades, barrier functions, and macrophage polarization in colonic tissues and cells were assessed in vivo and in vitro. The expression of TM9SF4 was compared between inflamed regions of ulcerative colitis patients and normal colon samples. RESULTS: In mouse models of IBD, genetic knockout of the TM9SF4 gene aggravated the disease symptoms. In colonic epithelial cells, short hairpin RNA-mediated knockdown of TM9SF4 expression promoted inflammation and increased ER stress. In macrophages, TM9SF4 knockdown promoted M1 macrophage polarization but suppressed M2 macrophage polarization. Genetic knockout/knockdown of TM9SF4 also disrupted epithelial barrier function. Mechanistically, TM9SF4 deficiency may act through Ca2+ store depletion and cytosolic acidification to induce an ER stress increase. Furthermore, the expression level of TM9SF4 was found to be much lower in the inflamed colon regions of human ulcerative colitis patients than in normal colon samples. CONCLUSIONS: Our study identified a novel IBD-associated protein, TM9SF4, the reduced expression of which can aggravate intestinal inflammation. Deficiency of TM9SF4 increases ER stress, promotes inflammation, and impairs the intestinal epithelial barrier to aggravate IBD.


Subject(s)
Colitis, Ulcerative , Endoplasmic Reticulum Stress , Membrane Proteins , Animals , Colitis, Ulcerative/genetics , Colitis, Ulcerative/metabolism , Genome-Wide Association Study , Humans , Inflammation/genetics , Inflammation/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Knockout
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