المؤلفون: Wang, Yali¹ huf2007@163.com, Ye, Qing¹, Cui, Yongqi¹, Wu, Yunjiang², Cao, Sipei^3,4, Hu, Feng⁵ huf2007@163.com

المصدر: Clinical Hemorheology & Microcirculation. Jun2024, p1-15. 15p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *SHEARING force, *PULMONARY hypertension, *TRP channels, *CYTOSKELETAL proteins

مستخلص: Pulmonary hypertension (PH) is a refractory disease characterized by elevated pulmonary artery pressure and resistance. Drag-reducing polymers (DRPs) are blood-soluble macromolecules that reduce vascular resistance by altering the blood dynamics and rheology. Our previous work indicated that polyethylene oxide (PEO) can significantly reduce the medial wall thickness and vascular resistance of the pulmonary arteries, but the specific mechanism is still unclear.This study was designed to investigate the role and mechanism of PEO on intracellular calcium [Ca2 +] i and cytoskeletal proteins of endothelial cells (ECs) induced by low shear stress (LSS) in PH. Primary Pulmonary Artery Endothelial Cells (PAECs) were subjected to steady LSS (1 dyn/cm2) or physiological shear stress (SS) (10 dyn/cm2) for 20 h in a BioFlux 200 flow system. Calcium influx assays were conducted to evaluate the mechanisms of PEO on [Ca2 +] i. Subsequently, taking the key protein that induces cytoskeletal remodeling, the regulatory light chain (RLC) phosphorylation, as the breakthrough point, this study focused on the two key pathways of PEO that regulate phosphorylation of RLC: Myosin light chain kinase (MLCK) and Rho-associated kinase (ROCK) pathways.Our current research revealed that PEO at LSS (1 dyn/cm2) significantly suppressed LSS-induced [Ca2 +] i and the expression level of transient receptor potential channel 1(TRPC1). In addition, ECs convert LSS stimuli into the upregulation of cytoskeletal proteins, including filamentous actin (F-actin), MLCK, ROCK, p-RLC, and pp-RLC. Further experiments using pharmacological inhibitors demonstrated that PEO at the LSS downregulated cytoskeleton-related proteins mainly through the ROCK and MLCK pathways.This study considered intracellular calcium and cytoskeleton rearrangement as entry points to study the application of PEO in the biomedical field, which has important theoretical significance and practical application value for the treatment of PH. [ABSTRACT FROM AUTHOR]

المؤلفون: Wang, Yu¹ (AUTHOR), Zhao, Min² (AUTHOR) zhaomin3112701@163.com, Li, Jing¹ (AUTHOR), Liu, Yue¹ (AUTHOR)

المصدر: Clinical & Experimental Pharmacology & Physiology. Jun2024, Vol. 51 Issue 6, p1-10. 10p.

مصطلحات موضوعية: *CEREBRAL hemorrhage, *MYOSIN light chain kinase, *PYROPTOSIS, *ADENOSINES, *MYOSIN, *CEREBRAL edema, *WESTERN immunoblotting

مستخلص: Intracerebral haemorrhage (ICH) presents significant challenges in clinical management because of the high morbidity and mortality, necessitating novel therapeutic approaches. This study aimed to assess the neuroprotective effects of loganin in a rat ICH model. Sprague–Dawley rats were used, subjected to a collagenase‐induced ICH model, followed by loganin treatment at doses of 2.5, 5 and 10 mg/kg. Neurological functions were evaluated using the modified neurological severity score (mNSS) and a rotarod test. Results indicated a significant improvement in neurological functions in loganin‐treated groups, evident from the mNSS and rotarod tests, suggesting dose‐dependent neuroprotection. Loganin also effectively reduced the blood–brain barrier (BBB) permeability and cerebral oedema. Additionally, it mitigated cellular pyroptosis, as shown by terminal deoxynucleotidyl transferase dUTP nick‐end labelling staining and western blot analysis, which indicated reduced levels of pyroptosis markers in treated rats. Furthermore, loganin's regulatory effects on the adenosine A2A receptor and myosin light chain kinase pathways were observed, potentially underpinning its protective mechanism against ICH. The study concludes that loganin exhibits significant neuroprotective properties in a rat ICH model, highlighting its potential as a novel therapeutic strategy. Despite promising results, the study needs further research to determine loganin's therapeutic potential in human ICH patients. This research paves the way for further exploration into loganin's clinical applications, potentially revolutionizing treatment strategies for patients suffering from intracerebral haemorrhage. [ABSTRACT FROM AUTHOR]

المؤلفون: Wrobel, Michal Hubert¹ (AUTHOR) m.wrobel@pan.olsztyn.pl, Mlynarczuk, Jaroslaw¹ (AUTHOR), Rekawiecki, Robert¹ (AUTHOR)

المصدر: Theriogenology. Apr2024, Vol. 218, p183-192. 10p.

مصطلحات موضوعية: *CARBARYL, *MYOSIN light chain kinase, *PYRETHROIDS, *CHOLINESTERASE reactivators, *PESTICIDES, *CARBAMATES, *CYCLOOXYGENASES, *UTERINE contraction

مستخلص: Previously studied classes of pesticides, including organochlorines, organophosphates and pyrethroids disturb the mechanism that causes bovine myometrial contractions. Hence, the aim of this study was to investigate the effects of carbaryl and thiram, which are representative carbamate pesticides commonly used in global agriculture, on the motor and secretory functions of bovine cervixes. Additionally, the impacts of these pesticides on intra- and intercellular signaling in vitro were estimated. In this study, cervical cells or strips were obtained from cows at days 18–20 of the estrous cycle and were treated with carbaryl or thiram. Neither carbamate (10 or 100 ng/ml) exerted cytotoxic effects. Carbaryl increased the level of mRNA (at a dose of 0.1 ng/ml) and protein (at both doses, 1 and 10 ng/ml) expression for the oxytocin receptor (OXTR), while thiram (at 0.1 and 10 ng/ml or 0.1–10 ng/ml, respectively) caused the opposite effects. Moreover, the level of the second messenger inositol-trisphosphate (IP3) was decreased by carbaryl (10 ng/ml) but increased by thiram (10 ng/ml). Only thiram decreased prostaglandin-endoperoxide synthase 2 (PTGS2 ; 0.1 ng/ml) and aldo-keto reductase family 1 , member B1 (AKR1B1; 0.1 ng/ml), and prostaglandin E synthase 2 (PTGES2; 0.1–10 ng/ml) mRNA expression, while thiram (0.1–10 ng/ml) and carbaryl (0.1 and 10 ng/ml) both decreased the release of PGF2α. Carbaryl (10 ng/ml) and thiram (10 ng/ml) also decreased the level of a gap junction protein (GAP). Moreover, carbaryl (10 ng/ml) decreased the level of myosin light chain kinase (MLCK). However, the strength of cervical contractions was increased by thiram (1 and 10 ng/ml) but decreased by carbaryl (1 and 10 ng/ml). Carbaryl increased the receptivity of cervical cells to oxytocin (OXT), but inhibited further transduction (IP3) of this signal. Hence, direct inhibition of cervical strip contraction may occur. In contrast, thiram mostly decreased the receptivity of cervical cells to OXT, while it stimulated the contraction of cervical strips. Moreover, compared to carbaryl, thiram more greatly affected the synthesis and release of prostaglandins. These results suggest that carbaryl and thiram disturb OXT signaling, PG secretion and cervical contraction in vitro. • Carbaryl increased OT receptivity of cervix, while thiram decreased it. • Carbaryl and thiram disturbed intra- and intercellular transduction of OT signals. • Carbaryl and thiram decreased PGF2α secretion from cervical cells. • Thiram increased cervical contraction in cows, while carbaryl decreased it. [ABSTRACT FROM AUTHOR]

المؤلفون: An, Zhonghua¹ (AUTHOR), Wang, Yitong¹ (AUTHOR), Wu, Mengran¹ (AUTHOR), Zheng, Haotian¹ (AUTHOR), Feng, Xuelin¹ (AUTHOR), Jiang, Yiming¹ (AUTHOR), Gong, Yanling¹ (AUTHOR) hanyu_ma@126.com

المصدر: International Journal of Food Engineering. Feb2024, Vol. 20 Issue 2, p141-150. 10p.

مصطلحات موضوعية: *SMOOTH muscle contraction, *MYOSIN light chain kinase, *ESSENTIAL oils, *FOURIER transform infrared spectroscopy, *SMOOTH muscle

مستخلص: Atractylodes chinensis volatile oil (ACVO) microcapsules were prepared with chitosan as parietal material. The optimal conditions for encapsulation were investigated by the Response Surface Method (RSM). ACVO microcapsules were characterized by scanning electron microscopy (SEM), particle size analyzer and Fourier Transform infrared spectroscopy (FTIR), respectively. In vitro release properties of ACVO microcapsules were investigated at pH 1.5 and 7.4, respectively. The effects of ACVO microcapsules on the length of rat gastric smooth muscle cells (GSMC), mRNA and protein expression of calmodulin (CaM) and myosin light chain kinase (MLCK) were investigated. Results showed that under optimal conditions, encapsulation efficiency (EE) was 82.19 %. ACVO microcapsules were spherical with a particle size of 1100 nm. ACVO microcapsules had a good release profile at pH 1.5, and the cumulative release within 72 h reached 85.32 %. Cell experiments showed that ACVO microcapsules (0.02, 0.04 μg/mL) had no effect on cell activity, while induced GSMC to contract, and improved the mRNA, protein expressions of CaM and MLCK in GSMC. [ABSTRACT FROM AUTHOR]

المؤلفون: Eunyoung Lee¹, May, Herman^1,2, Kazmierczak, Katarzyna², Jingsheng Liang², Nhu Nguyen¹, Hill, Joseph A.¹, Gillette, Thomas G.¹, Szczesna-Cordary, Danuta², Chang, Audrey N.^1,3 AudreyN.Chang@UTSouthwestern.edu

المصدر: Journal of Biological Chemistry. Feb2024, Vol. 300 Issue 2, p1-14. 14p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *HEART, *MYOSIN, *MYOCARDIUM

مستخلص: The physiological importance of cardiac myosin regulatory light chain (RLC) phosphorylation by its dedicated cardiac myosin light chain kinase has been established in both humans and mice. Constitutive RLC-phosphorylation, regulated by the balanced activities of cardiac myosin light chain kinase and myosin light chain phosphatase (MLCP), is fundamental to the biochemical and physiological properties of myofilaments. However, limited information is available on cardiac MLCP. In this study, we hypothesized that the striated muscle-specific MLCP regulatory subunit, MYPT2, targets the phosphatase catalytic subunit to cardiac myosin, contributing to the maintenance of cardiac function in vivo through the regulation of RLC-phosphorylation. To test this hypothesis, we generated a floxed-PPP1R12B mouse model crossed with a cardiac-specific Mer-Cre-Mer to conditionally ablate MYPT2 in adult cardiomyocytes. Immunofluorescence microscopy using the gene-ablated tissue as a control confirmed the localization of MYPT2 to regions where it overlaps with a subset of RLC. Biochemical analysis revealed an increase in RLC-phosphorylation in vivo. The loss of MYPT2 demonstrated significant protection against pressure overload-induced hypertrophy, as evidenced by heart weight, qPCR of hypertrophy-associated genes, measurements of myocyte diameters, and expression of β-MHC protein. Furthermore, mantATP chase assays revealed an increased ratio of myosin heads distributed to the interfilament space in MYPT2-ablated heart muscle fibers, confirming that RLC-phosphorylation regulated by MLCP, enhances cardiac performance in vivo. Our findings establish MYPT2 as the regulatory subunit of cardiac MLCP, distinct from the ubiquitously expressed canonical smooth muscle MLCP. Targeting MYPT2 to increase cardiac RLC-phosphorylation in vivo may improve baseline cardiac performance, thereby attenuating pathological hypertrophy. [ABSTRACT FROM AUTHOR]

المؤلفون: ALTUN, Muammer¹, BALCAN, Erdal², BATIR, Sevinç², GÖKMEN, Mehmet Hilmi¹ mehmethilmi93@gmail.com, ÖZGÜNEŞ, Şule¹, ÖZTEL, Zübeyde²

المصدر: Turkish Journal of Medical Sciences. 2024, Vol. 54 Issue 1, p148-156. 9p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *GENE expression, *BRAIN-derived neurotrophic factor, *KNEE joint, *ANGIOTENSIN converting enzyme

مستخلص: Background/aim: Although high muscle strength worsens the sense of force, it is unknown whether there is a relationship between this deterioration and the underlying molecular mechanisms. This study examined the relationship between decreased force sense (FS) acuity and strength-related gene expressions. Materials and methods: Maximal voluntary isometric contraction (MVIC) and FS (50% MVIC) tests were performed on the knee joints of twenty-two subjects. The expression analyses were evaluated by qRT-PCR in blood samples taken before, after MVIC, after 50% MVIC, and 15 min after the test. Results: MVIC and FS error values were significantly correlated with each other (r = .659, p = .001). The qRT-PCR analyses demonstrated that the expressed mRNAs of the interleukin 6 (IL-6), alpha-actinin 3 (ACTN3), angiotensin-converting enzyme (ACE), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor receptor (CNTFR) genes dramatically increased until 50% MVIC and subsequently decreased 15 min after the exercise (p < .05). The muscle-specific creatine kinase (CKMM), myosin light chain kinase (MLCK), and G-protein ß3 subunit (GNB3) genes reached their peak expression levels 30 min after MVIC (p < .05). ACE and ACTN3 gene expression increased significantly in parallel with the increased FS error (p < .05). These gene expression fluctuations observed at 50% MVIC and after the rest could be related to changes in cellular metabolism leading to fatigue. Conclusion: The time points of gene expression levels during exercise need to be considered. The force acuity of those whose maximal force develops too much may deteriorate. [ABSTRACT FROM AUTHOR]

المؤلفون: Kutsuzawa, Naokata¹ (AUTHOR), Ito, Yoko¹ (AUTHOR) itoy@tokai.ac.jp, Kagawa, Shizuko¹ (AUTHOR), Kohno, Chinatsu¹ (AUTHOR), Takiguchi, Hiroto¹ (AUTHOR), Asano, Koichiro¹ (AUTHOR)

المصدر: PLoS ONE. 12/27/2023, Vol. 18 Issue 12, p1-16. 16p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *RESPIRATORY distress syndrome, *TUMOR necrosis factors, *CELL junctions, *PULMONARY edema, *EPITHELIAL cells

مستخلص: Alveolar barrier dysfunction is one of the major pathophysiological changes in acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). In ALI/ARDS, tumor necrosis factor-alpha (TNFα) disrupts the barriers of alveolar epithelium and endothelium. Glucocorticoids (GCs) exert anti-inflammatory effects and ameliorate pulmonary edema in ALI/ARDS. However, the involvement of GCs in the restoration of alveolar epithelial barrier dysfunction has not been extensively studied. Here, we elucidated that dexamethasone (Dex) restored TNFα-induced alveolar epithelial barrier dysfunction in vitro using primary rat alveolar epithelial cells isolated from Sprague–Dawley rats. Moreover, Dex promoted the alveolar epithelial cell barrier integrity by initiating GC receptor-mediated signaling via the downregulation of myosin light chain kinase (MLCK) expression and the dephosphorylation of myosin light chain (MLC) 2. Further investigation revealed that Dex enhanced the expression of zonula occludens-1 (ZO-1), a tight junction-related protein, at intercellular junction sites. These findings suggest that GCs strengthen the integrity of the alveolar epithelial barrier in ALI/ARDS via the GR-MLCK-pMLC2 axis. [ABSTRACT FROM AUTHOR]

المؤلفون: Guo, Zhi^1,2,3 (AUTHOR), Yang, Xuan^1,2,3 (AUTHOR), Wu, Meizhu^1,2,3 (AUTHOR), Shen, Aling^1,2,3 (AUTHOR), Li, Jiapeng^2,3,4 (AUTHOR), Zhang, Xiuli^1,2,3 (AUTHOR), Cheng, Ying^2,3 (AUTHOR), Xie, Qiurong^1,2,3 (AUTHOR) 2020025@fjtcm.edu.cn, Peng, Jun^1,2,3 (AUTHOR) pjunlab@hotmail.com

المصدر: Pharmaceutical Biology. Dec2023, Vol. 61 Issue 1, p858-867. 10p.

مصطلحات موضوعية: *ANGIOTENSIN II, *MYOSIN light chain kinase, *VASCULAR smooth muscle, *BLOOD pressure, *PULSE wave analysis, *ABDOMINAL aorta, *VASOCONSTRICTION, *INTRACELLULAR calcium

مصطلحات جغرافية: CHINA

مستخلص: Gastrodin has been used as antihypertension therapy in China; however, the mechanisms underlying the effects of gastrodin have yet to be fully elucidated. To explore the therapeutic efficiency of gastrodin as an antihypertensive and determine the mechanisms underlying this effect. C57BL/6 mice were continuously administered angiotensin II (Ang II) (500 ng/kg/min) to induce hypertension. Mice were randomly divided into control, Ang II and Ang II + gastrodin groups. Mice received intragastric administration of gastrodin (5 mg/kg) or double distilled water once a day for 4 weeks. Blood pressure, pulse wave velocity (PWV), thickness of the abdominal aorta, pathological morphology and differential expression transcripts (DETs) were assessed. Abdominal aorta rings and primary isolated vascular smooth muscle cells were subjected to Ang II stimulation to induce hypertension as ex vivo and in vitro models, respectively. Vascular ring tension, release of Ca2+ and levels of proteins involved in the myosin light chain kinase (MLCK)/phospho-myosin light chain 2 (p-MLC2) pathway were determined. Gastrodin treatment attenuated increases in blood pressure, PWV and thickness of the abdominal aorta. Treatment with gastrodin resulted in 2785 DETs and the enrichment of vascular contraction and calcium signalling pathways. Gastrodin treatment attenuated Ang II-induced vasoconstriction, produced a norepinephrine-precontracted vasodilation effect (attenuated by verapamil), and reduced intracellular Ca2+ release. Furthermore, gastrodin suppressed activation of the MLCK/p-MLC2 pathway in vivo and in vitro. Gastrodin treatment lowers blood pressure, suppresses Ang II-induced vascular contraction and MLCK/p-MLC2 pathway activation, thereby demonstrating the mechanisms underlying the therapeutic efficacy of gastrodin as an antihypertensive. [ABSTRACT FROM AUTHOR]

المؤلفون: Xie, Yong^1,2,3,4 (AUTHOR), Luo, Zixiang^1,2,3,4 (AUTHOR), Peng, Wei^1,2,3,4 (AUTHOR), Liu, Yudong^1,2,3,4 (AUTHOR), Yuan, Feifei^1,2,3,4 (AUTHOR), Xu, Jiaqi^1,2,3,4 (AUTHOR), Sun, Yi^1,2,3,4 (AUTHOR), Lu, Hongbin^2,3,4,5 (AUTHOR), Wu, Tianding^1,2,3,4 (AUTHOR) tiandingwu@hotmail.com, Jiang, Liyuan^1,2,3,4 (AUTHOR) jiangliyuan01@hotmail.com, Hu, Jianzhong^1,2,3,4 (AUTHOR) jianzhonghu@hotmail.com

المصدر: Journal of Neuroinflammation. 11/11/2023, Vol. 20 Issue 1, p1-22. 22p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *SPINAL cord injuries, *PERMEABILITY, *MACROPHAGES, *GENE expression

مستخلص: Spinal cord injury (SCI) can prompt an immediate disruption to the blood–spinal cord barrier (BSCB). Restoring the integrity of this barrier is vital for the recovery of neurological function post-SCI. The UTX protein, a histone demethylase, has been shown in previous research to promote vascular regeneration and neurological recovery in mice with SCI. However, it is unclear whether UTX knockout could facilitate the recovery of the BSCB by reducing its permeability. In this study, we systematically studied BSCB disruption and permeability at different time points after SCI and found that conditional UTX deletion in endothelial cells (ECs) can reduce BSCB permeability, decrease inflammatory cell infiltration and ROS production, and improve neurological function recovery after SCI. Subsequently, we used RNA sequencing and ChIP-qPCR to confirm that conditional UTX knockout in ECs can down-regulate expression of myosin light chain kinase (MLCK), which specifically mediates myosin light chain (MLC) phosphorylation and is involved in actin contraction, cell retraction, and tight junctions (TJs) protein integrity. Moreover, we found that MLCK overexpression can increase the ratio of p-MLC/MLC, further break TJs, and exacerbate BSCB deterioration. Overall, our findings indicate that UTX knockout could inhibit the MLCK/p-MLC pathway, resulting in decreased BSCB permeability, and ultimately promoting neurological recovery in mice. These results suggest that UTX is a promising new target for treating SCI. [ABSTRACT FROM AUTHOR]

المؤلفون: Tito, Annalisa¹ (AUTHOR) annalisa@arterrabio.it, Niespolo, Chiara¹ (AUTHOR), Monti, Maria Chiara² (AUTHOR), Colucci, Maria Gabriella^1,3 (AUTHOR), Fogliano, Vincenzo^1,4 (AUTHOR)

المصدر: Biochemical & Biophysical Research Communications. Nov2023, Vol. 681, p36-40. 5p.

مصطلحات موضوعية: *MYOSIN light chain kinase, *CELL culture, *LIGNANS, *CELL contraction, *NEOLIGNANS, *CHO cell

مستخلص: Piezo1 and Piezo2 are mechanoreceptors involved in sensing both internal and external mechanical forces converting them in electrical signals to the brain. Piezo1 is mainly expressed in the endothelial system and in epidermis sensing shear stress and light touch. The internal traction forces generated by Myosin Light Chain Kinase (MYLK) activate Piezo1, regulating cell contraction. We observed Oenothera biennis cell culture hydro-soluble extract (ObHEx) activated MYLK regulating cell contraction ability. The aim of this work was to test the hypothesis that ObHEx activates Piezo1 through MYLK pathway using CHO cell overexpressing Piezo1, HUVEC and SHSY5Y cells endogenously expressing high levels of Piezo1. Results showed that ObHEx extracts were able to activate Piezo1 and the effect is due to Liriodendrin and Salvadoraside, the two most abundant lignans produced by the cell culture. The effect is lost in presence of MYLK specific inhibitors confirming the key role of this pathway and providing indication about the mechanism of action in Piezo1 activation by lignans. In summary, these results confirmed the connection between Piezo1 and MYLK, opening the possibility of using lignans-containing natural extracts to activate Piezo1. • We describe Oenothera biennis as the first natural extract activating Piezo1 channel. • Activation of Piezo1 is mediated by two lignans, liriodendrin and salvadoraside. • Lignans act with a Yoda-like mechanism, as their effect is abolished by Dooku1. • Piezo1 activation is also revoked in the presence of a MYLK inhibitor, ML-7. • Confirmed association between Piezo1 and MYLK signalling mechanism. [ABSTRACT FROM AUTHOR]