Differential Analysis of Erythrocyte Flexibility of PbK173 Artemisinin-sensitive Strains / 中国实验方剂学杂志

ObjectiveTo detect the flexibility differences of Plasmodium berghei K173 （PbK173）-infected red blood cells with varying degrees of sensitivity to artemisinin-based drugs and to preliminarily explore the underlying mechanisms of the differences. MethodA total of 102 specific-pathogen-free （SPF） male C57BL/6 mice were randomly divided into three groups， with 30 mice each in the control group and PbK173-resistant （PbK173-R） group， and 42 mice in the PbK173-sensitive （PbK173-S） group. Except for the control group， the rest groups were vaccinated with 1×107 PbK173-S/PbK173-R infected red blood cells to establish a mouse malaria model. During the administration and recovery periods （control group， PbK173-R/PbK173-S）， dihydroartemisinin （DHA， 40 mg·kg-1） and malaridine （MD， 6 mg·kg-1） were administered continuously for four days. Peripheral blood was taken from the PbK173-S/PbK173-R groups with an infection rate equal to or greater than 20%. Peripheral blood and each organ were taken on the first day at the end of administration （dosing period） and on the fifth day at the end of administration （recovery period）， and blood parameters and organ indices of each group were examined. The osmotic fragility of peripheral blood red blood cells in each group was detected using the red blood cell osmotic fragility test. Western blot was applied to determine the levels of Piezo1 and Band3 proteins in the red blood cell membrane. ResultDuring the administration and recovery periods， there were no significant differences between the PbK173-S MD group and the DHA group. During the administration period， there were no significant differences in hematological parameters between PbK173-S and PbK173-R in the MD group. However， during the recovery period， the red blood cell count， hemoglobin concentration and hematocrit of the PbK173-R group were significantly higher than those of the PbK173-S group （P<0.05） in the MD group. Compared with that of the control group， the osmotic fragility of the PbK173-S/PbK173-R groups was significantly enhanced （P<0.01）， and the osmotic fragility of the PbK173-S group was significantly stronger than that of the PbK173-R group （P<0.01）. The osmotic fragility of red blood cells in the PbK173-S group during the administration period was significantly stronger than that in the control group and PbK173-R group during the administration period （P<0.01）. The osmotic fragility of red blood cells in the PbK173-R group during the recovery period was significantly higher than that in the control group during the administration period and the PbK173-S group during the recovery period （P<0.05）. Compared with those in the control group， the Piezo1 protein and Band3 protein in the red blood cell membrane of the PbK173-S group were significantly reduced （P<0.01）. Compared with those in the PbK173-R group， the Piezo1 protein and Band 3 protein in the red blood cell membrane of the PbK173-S group were significantly reduced. ConclusionThe flexibility of PbK173-infected red blood cells with different sensitivities to artemisinins differed. Plasmodium-infected red blood cells significantly reduced the levels of Piezo1 and Band3 proteins in the red blood cell membrane， and the erythrocyte flexibility exhibited a decreasing trend in the following order： normal group， PbK173-R group， and PbK173-S group.

Mechanosensitive ion channel Piezo1 induces senescence of atrial fibroblasts by activating β-catenin / 中国药理学通报

Aim To observe whether the mechanosensitive ion channel Piezo1 was involved in the senescence of atrial fibroblasts by activating β-catenin based on our previous study which found marked increase of Piezo1 mRNA in senescent atrial fibroblasts. Methods Primary mouse atrial fibroblasts (MAFs) were isolated from male C57BL/6 mice (3-4 weeks) by enzyme digestion, and tert-butyl hydroperoxide (TBHP) was used to induce the senescence of cells. The ratio of senescent cells was detected by senescence-associated β-galactosidase (SA-β-Gal) staining. The protein levels of Piezo1, β-catenin/p-β-catenin, senescence-associated proteins p53 and p21 in the cells treated with TBHP (100 μmol · L

The expression and significance of Piezo1 in chronic rhinosinusitis with nasal polyps / 临床耳鼻咽喉头颈外科杂志

Objective:To explore the expression and importance of Piezo1, E-cadherin, and Vimentin in nasal polyps patients. Methods:Thirty-five patients undergoing endoscopic sinus surgery under general anesthesia were streamed into 20 cases of nasal polyps（NP group） and 15 cases of simple septoplasty without any sinus disease（Control group）. Immunofluorescence staining and Western Blot were applied to detect the protein level of Piezo1, E-cadherin, and Vimentin in NP tissues and nasal polyp-derived primary human nasal epithelial cells（pHNECs）. Also, BEAS-2B cell lines were treated with human TGF-β1 protein to establish epithelial mesenchymal transition（EMT） model in vitro and quantitative real-time polymerase chain reaction were used to calculate Piezo1 and above biomarkers in the model. Results:Compared with control group, Piezo1 and Vimentin showed higher level while E-cadherin was lower in NP tissues and pHNECs.In EMT model in vitro, Piezo1 and Vimentin were demonstrated higher expression with decreased level of E-cadherin. Conclusion:The tendency of Piezo1 is consistent with the mesenchymal-related biomarker Vimentin, going against with epithelial-related biomarker E-cadherin, implying its involvement with EMT process in nasal polyps.

Biomechanopharmacology of Chinese Medicine Based on Mechano-ion Channel Piezo1： A Review / 中国实验方剂学杂志

Ischemic stroke is one of the leading causes of death and disability worldwide. In Han dynasty， HUA Tuo proposed the original preventive medicine idea that "with good blood circulation， the disease cannot be born"， which opened a broad space for the cross-research of blood-related mechanical factors and pharmacology. In the pathogenesis of ischemic stroke， mechanical factors comprehensively affect the function and crosstalk of platelets and endothelial cells. In recent years， as the well-known effects on thrombosis and stroke， more attention has been paid to hemodynamic factors as the participants involved in pathological mechanisms and potential therapeutic targets of ischemic stroke. The mechanical force ion channel Piezo1 widely exists on the surface of many types of cells. Besides being regulated by chemical and endogenous substances， Piezo1 responds to different mechanical conditions， regulates the opening and closing of channels， and activates different downstream signaling pathways. Piezo1 is now regarded as an important connection between mechanical and biochemical signals. A variety of Chinese medicine can affect the activity of Piezo1 protein， which may prevent and treat thrombotic diseases such as ischemic stroke through Piezo1 protein. In this paper， the effects of Piezo1 protein on the physiological and pathological functions of endothelial cells and platelet under different mechanical conditions and the role of Piezo1 in the process of thrombosis were reviewed， as well as the effects of Chinese medicine， chemical medicine， and endogenous substances targeting Piezo1 channel. These could provide new ideas for further exploring the mechanisms of Chinese medicines in activating blood circulation， developing new drugs， and deepening biomechanical-pharmacology research.

Clinical study on the expression of Piezo1 in small intestinal mucosa of 57 patients with Crohn′s disease / 中华消化杂志

Objective:To investigate the expression of Piezo1 in small intestinal mucosal epithelial cells of patients with Crohn′s disease (CD) and its clinical correlation with CD.Methods:From January 1st 2010 to November 30th 2020, the clinical data including age, gender, disease location and biological behavior, etc of 57 patients with CD (CD group) who underwent surgery at The First Affiliated Hospital of Anhui Medical University were retrospectively. And at same time the normal samll intestinal epithelial tissues of 10 healthy individuals who underwent colonoscopy were collected as the healthy control group. The expression of Piezo1 in small intestinal epithelial cells of CD patients with different disease sites, biological behavior and disease activity were detected by immunofluorescence staining and hematoxylin-eosin staining. The histological score system and intestinal fibrosis score were used to analyze the inflammation and fibrosis of the intestinal tissues of patients with CD. Semi-quantitative analysis of Piezo1 in small intestinal epithelial cells was analyzed by ImageJ software. And the correlation between Piezo1 expression and clinical characteristics and pathological features of small intestine was also analyzed. Independent sample t test and analysis of variance were used for statistical analysis. Results:In CD group, there were 37 males (64.9%) and 20 females (35.1%). The age was (39.1±14.2) years old, ranged from 18 to 71 years old, and the average duration of the disease was (26.5±24.1) months. There were 29 cases (50.9%)of ileal type, 26 cases (45.6%) of ileocolonin type and 2 cases (3.5%) of colonic type. There were 12 cases (21.1%) of non-penetrating non-stenotic type, 31 cases (54.4%) of stenotic type and 14 cases (24.6%) of penetrating type. There were 47 cases (82.5%) with moderate activity and 10 cases (17.5%) with severe activity. There were 17 cases (29.8%) of moderate intestinal inflammation, 40 cases (70.2%) of severe intestinal inflammation. The score of intestinal fibrosis in six cases (10.5%) was 1, 28 cases (49.1%) was 2, 18 cases (31.6%) was 3, five cases was 4. The relative expression level of Piezo1 in intestinal mucosal epithelial cells of CD group was higher than that of healthy control group (12.9±4.6 vs. 8.5±1.1), the relative expression of Piezo1 in intestinal mucosal epithelia cells of stenotic type and penetrating type CD patients were both higher than that of non-penetrating and non-stenotic CD patients (12.6±3.8 and 9.8±2.4 vs. 6.0±1.3), and the differences were all statistically significant ( t=3.00, -3.66 and -3.32, all P<0.01). The relative expression of Piezo1 in small intestinal epithelial cells of CD patients with severe intestinal inflammation was higher than that of CD patients with moderate intestinal inflammation (13.1±4.0 vs. 9.7±3.1), and the difference was statistically significant ( t=-2.65, P<0.05). The relative expression levels of Piezo1 in small intestinal epithelial cells of patients with intestinal fibrosis score of 4, 3, 2 and 1 were 17.6±5.2, 12.6±1.7, 9.1±2.1 and 5.8±1.1, respectively; the relative expression levels of Piezo1 in intestinal epithelial cells of patients scored 4 were higher than that of patients scored 3, 2 and 1, and that of patients scored 3 was higher than patients scored 2 and 1, and that of patients scored 2 was higher than that of patients scored 1, and the differences were all statistically significant ( t=-2.98, -5.10, -3.84, 4.60, 6.55 and 2.56, all P<0.05). The relative expression of Piezo1 in intestinal mucosal epithelial cells was related to the severity of intestinal inflammation and fibrosis. The more severe the intestinal inflammation and fibrosis, the higher the relative expression of Piezo1 in intestinal mucosal epithelial cells. Conclusions:The relative expression of Piezo1 in small intestinal epithelial cells is related to the biological behavior and the severity of intestinal inflammation and fibrosis of CD. It is speculated that the expression of Piezo1 in small intestinal epithelial cells may be clinically related to the process of intestinal wall fibrosis in CD to some extent, however whether it plays an important role in the process of intestinal wall fibrosis in CD and its specific mechanism need to be further studied.

Mechanisms of the mechanically activated ion channel Piezo1 protein in mediating osteogenic differentiation of periodontal ligament stem cells via the Notch signaling pathway / 华西口腔医学杂志

OBJECTIVE@#To explore the mechanism of Piezo1 protein in mediating the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) via the Notch signaling pathway.@*METHODS@#In this study, young permanent teeth extracted from impacted teeth of 8-14-year-
old children from January 1, 2016 to January 1, 2018 in the Department of Orthodontic, Beijing Children's Hospital were selected as cell sources. hPDLSCs were extracted by enzymatic digestion. Immunohistochemical staining was used to detect the expression of keratin and vimentin, and flow cytometry was used to identify the markers (CD146 and STRO-1) of hPDLSCs. The construction and screening of Piezo1 siRNA gene interference vector and Piezo1 gene overexpression plasmid were completed. Flexcell 4000T mechanical distraction stress instrument was used to construct hPDLSC cell model in vitro. According to the preliminary results, the experiment was divided into five groups: siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group. Real time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of Piezo1, Notch1, alkaline phosphatase (ALP), Runt-related transcription factor 2 (Runx2), osteocalcin (OCN), and bone sialoprotein (BSP). Western blot was used to detect the expression of ALP and Runx2. Fluo-3 AM probe was used to detect intracellular calcium content.@*RESULTS@#Vimentin staining of hPDLSCs was positive, and keratin staining was negative. Flow cytometry was used to detect the expression of STRO-1 and CD146, markers of hPDLSC. Empty viral vectors, siRNA-Piezo1 interference sequence, and Piezo1 overexpression vector sequence could be transfected into hPDLSC by lentivirus, and the transfection efficiency was high (approximately 90%). The reverse transcription-polymerase chain reaction (RT-PCR) results showed that there were significant differences in Piezo1 gene levels among the siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group (F=9.573, P<0.05). The level of Piezo1 in the overexpression group was significantly higher than that in the siRNA interference group (q=3.893, P<0.05). The level of Piezo1 in the stretch stress group was significantly higher than that in the blank control group (q=2.006, P<0.05). The expression of Notch1 and osteogenic genes ALP, Runx2, OCN, and BSP had the same trend. Western blot results showed that there were significant differences in the expression of ALP in the siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group (F=11.207, P<0.001). The expression level of ALP in the overexpression group was significantly higher than that in the siRNA interference group (q=2.991, P<0.05). The expression of ALP in the stretch stress group was significantly higher than that in the blank control group (q=3.007, P<0.05). The expression of Runx2 protein showed the same trend. The intracellular calcium fluorescence intensity of the overexpression group was significantly higher than that of the siRNA interference group, and the intracellular calcium fluorescence intensity of the stretch stress group was significantly higher than that of the siRNA interference group.@*CONCLUSIONS@#Mechanical stretch stress can promote the expression of Piezo1 protein. Ca2+ is the second messenger, activates the Notch1 signaling pathway and the expression of ALP, Runx2, OCN, and BSP; and promotes the osteogenic differentiation of hPDLSC. The siRNA-Piezo1 interfering plasmid can block this process. On the contrary, the overexpression plasmid of Piezo1 can promote the osteogenic differentiation of PDLSCs.

Progress in Research on Mechanosensitive Ion Channel Piezo1/2 in Digestive System Diseases / 胃肠病学

Piezo proteins, including Piezo1, Piezo2, are non-selective mechanosensitive ion channels. They have similar biophysical characteristics, which can transform mechanical signals into biological electric signals. Studies have shown that Piezo proteins play important roles in mechanical-relevant physiological functions and pathophysiological changes of a variety of organs, including gastrointestinal tract. This article reviewed the relationship between Piezo1/2 proteins and digestive system diseases, and discussed the roles of Piezo1/2 under mechanical stress in the development of digestive system diseases, so as to provide a novel target in the study of pathogenesis and treatment of relevant digestive system diseases.

Research advances of mechanically sensitive ion channel Piezo1 in cardiovascular diseases / 中国临床药理学与治疗学

Mechanically sensitive ion channels play an important role in the cells' perception of external pressure and the growth of tissues and organs, and participate in the regulation of various cell functions. Among them, Piezo1 is a non-selective mechanically sensitive ion channel, which mainly exists in endothelial cells and vascular smooth muscle cells. The regulation of vascular function affects the progression of cardiovascular diseases such as atherosclerosis and hypertension. This article mainly reviews the role of Piezo1 in cardiovascular diseases, and provides new directions for the clinical intervention research of cardiovascular diseases.

Effect of knocking down Piezo1 mechanically sensitive protein on migration of MC3T3-E1 osteoblast cells / 中国修复重建外科杂志

Objective: To discuss the effect of Piezo1 mechanically sensitive protein in migration process of mouse MC3T3-E1 osteoblast cells. Methods: The 5th-10th generation mouse MC3T3-E1 osteoblasts were divided into Piezo1-small interfering RNA (siRNA) transfection group (group A), negative control group (group B), and blank control group (group C). Piezo1-siRNA or negative control siRNA was transfected into mouse MC3T3-E1 osteoblasts by siRNA transfection reagent, respectively; group C was only added with siRNA transfection reagent; and the cell morphology was observed under inverted phase contrast microscope and fluorescence microscope, and the transfection efficiency was calculated. The expression of Piezo1 protein was detected by immunofluorescence staining and Western blot. Transwell cell migration assay and cell scratch assay were used to detect the migration of MC3T3-E1 osteoblasts after Piezo1-siRNA transfection. Results: After 48 hours of transfection, group A showed a slight increase in cell volume and mutant growth, but cell colonies decreased, suspension cells increased and cell fragments increased when compared with untransfected cells. Under fluorescence microscope, green fluorescence was observed in MC3T3-E1 osteoblasts of group B, and the transfection efficiency was 68.56%±4.12%. Immunofluorescence staining and Western blot results showed that the expression level of Piezo1 protein in group A was significantly lower than that in groups B and C ( P0.05). Transwell cell migration assay and cell scratch assay showed that the number of cells per hole and the scratch healing rate of cells cultured for 1-4 days in group A were significantly lower than those in groups B and C ( P0.05). Conclusion: Piezo1 knocked down by siRNA can inhibit the migration ability of MC3T3-E1 osteoblast cells.

Expression characteristics of Piezo1 protein in stress models of human degenerative chondrocytes / 中国骨伤

<p><b>OBJECTIVE</b>To explore the expression characteristics of new mechanosensitive ion channel Piezo1 protein in stress models of human degenerative chondrocytes.</p><p><b>METHODS</b>The stress stimulation model of human degenerative chondrocytes in vitro was constructed. Multi-channel cell stretch stress loading system FX-4000T was used to treat chondrocytes. According to the results of pre-test, the loading frequency of 0.5 Hz and the cell elongation of 20% were loaded. According to cell processing time, it was divided into 0 h, 2 h, 12 h, 24 h and 48 h mechanical stress group. The RT-PCR and Western-blot were used to test the expression of the Piezo1, also the Laser scanning confocal microscope (LSCM) was used to test the intensity of the fluorescence of the Piezo1.</p><p><b>RESULTS</b>(1)The result of the RT-PCR showed that the expression of the Piezo1 in the 2 h group was higher than the 0 h group(13.917, 0.037 1, <0.05). The expression of the piezo1 in the 24 h group was the highest. While the expression of the piezo1 in the 48 h group was lower than the expression of the piezo1 in the 24 h group(13.917, 0.049 5, <0.05). (2)The result of the Western-blot showed that the 2 h group was higher than the 0 h group(19.341, 0.037 1, <0.05). The expression of the 24 h had the highest expression which was higher than the 48 h group(19.341, 0.017 7, <0.05). (3)The Piezo1 protein was extensively expressed in the cytoplasm and nucleus of the nucleus pulposus cells. And with the increase of stress processing time, the fluorescence intensity of the protein also increased.</p><p><b>CONCLUSIONS</b>In human degeneration cartilage cells, the new mechanio sensitive ion channel Piezo1 protein has a trace expression. After loading periodic mechanical tensile force, the expression of Piezo1 protein increases with time dependence.</p>

Effects of Fluid Shear Stress on Gene Expression of Piezo1 in the Cells During Osteogenic Differentiation / 医用生物力学

Objective To investigate the gene expression of Piezo1 in four types of bone cells at different stages of osteogenic differentiation under fluid shear stress (FSS). Methods The mouse-derived mesenchymal stem cells (MSC), osteoblast-like cells MC3T3-E1, post-osteoblasts MLO-A5 and osteocytes MLO-Y4 were exposed to FSS at different magnitude (0.1, 1.1 Pa) with a custom-made cone-plate flow chamber for 0.5, 1, 3, 6, 12 h, respectively. The expression of Piezo1 mRNA was assessed by quantitative real-time polymerase chain reaction. Results Both Piezo1 and Piezo2 were expressed in four types of bone cells. The expression of Piezo1 was significantly up-regulated in all cells under FSS stimulation, and the expression level under 1.1 Pa FSS was significantly higher than that under 0.1 Pa FSS. In addition, the expression of Piezo1 in MSC, MC3T3-E1 and MLO-A5 cells increased to the highest level at 1 h under FSS stimulation. The expression of Piezo1 in MC3T3-E1 cells was much higher than that in the other three types of cells. Conclusions The expression of Piezo1 was related to the process of osteogenic differentiation, FSS level and loading time, and this research finding is of great significance to reveal the mechanism of mechanotransduction in bone tissues and to establish clinical treatment for bone diseases.