AIM:To investigate the mechanism of Piezo1 channel activation promoting the increase in intra-cellular Ca2+ concentration([Ca2+]i)of rat coronary artery smooth muscle cells(CASMCs).METHODS:The primary CASMCs of SD rats were cultured,and the expression and subcellular localization of Piezo1 in the cells were observed by immunofluorescence staining.The Piezo1 and stromal interaction molecule 1(STIM1)in CASMCs were knocked down by siRNA transfection,and the expression levels of the proteins were detected by Western blot.Utilizing laser confocal mi-croscopy,the change of[Ca2+]i in CASMCs was detected by Fluo-4 AM fluorescent probes.RESULTS:It was confirmed by immunofluorescence staining that the expression of Piezo1 existed in primary rat CASMCs.Immunofluorescence staining also showed that Piezo1 was co-located with sarco-/endoplasmic reticulum Ca2+-ATPase 2(SERCA2),mitochondrial outer membrane protein TOM20 and nuclear membrane protein lamin B1.Western blot results showed that the protein expres-sion levels of STIM1 and Piezo1 were significantly down-regulated by siRNA transfection(P<0.05).Compared with con-trol group,Yoda1,the agonist of Piezo1,could increase the extracellular Ca2+ influx of CASMCs(P<0.01).However,the Ca2+ influx mediated by Yoda1 was not affected by the inhibition of L-type calcium channels.Treatment with Yoda1 in-creased the intracellular Ca2+ release of CASMCs(P<0.01).However,inhibition of calcium channels on endoplasmic re-ticulum,ryanodine receptor and inositol 1,4,5-triphosphate receptor,did not affect intracellular Ca2+ release mediated by Yoda1.After the Ca2+ in endoplasmic reticulum was emptied using thapsigargin(TG),Yoda1 also mediated the Ca2+ re-lease of other organelles in CASMCs(P<0.01).After inhibition of L-type calcium channels,treatment with store-operated calcium channel(SOCC)inhibitor BTP2 or knockdown of STIM1 led to the decrease in extracellular Ca2+ influx of CASMCs mediated by Yoda1(P<0.01).Treatment with TG increased the release of Ca2+ from the endoplasmic reticulum of CASMCs after knockdown of Piezo1(P<0.05),but the extracellular Ca2+ influx mediated by TG was not affected.After inhibition of L-type calcium channels and SOCC,knockdown of Piezo1 led to the decreases in intracellular Ca2+ release and extracellular Ca2+ influx induced by Yoda1(P<0.01).CONCLUSION:The Piezo1 agonist orchestrates the influx of extracellular Ca2+ by activating Piezo1 channels on the cell membrane and inducing the indirect activation of SOCC.More-over,it facilitates the release of Ca2+ from organelles.Consequently,these pathways synergistically elevate the[Ca2+]i of rat CASMCs.

AIM:To investigate the influence of fat mass and obesity-associated(Fto)gene on the aberrant contraction of aortic smooth muscle in diabetes mellitus(DM)mice,and to explore the mechanism of Fto gene underlying the calcium regulation.METHODS:Smooth muscle-specific Fto gene knockout(FtoSMKO)mice were generated using Cre-loxP technology.The experiment involved 3 groups of mice:wild-type(WT)group,DM model group and FtoSMKO-DM group,with 15 mice in each group.In DM group and FtoSMKO-DM group,type 1 DM was induced by intraperitoneal injec-tion of streptozotocin.The mice in WT group were injected with equal volume of citric acid-sodium citrate buffer solution.The influences of different drugs on the contraction responses of aortic smooth muscle in mice were analyzed using a multi-myograph system.The expression level of FTO protein in the aortic tissues was detected by Western blot.RESULTS:(1)Compared with WT mice,the expression levels of FTO protein in the aortic tissues of DM mice were significantly in-creased(P＜0.01).(2)The expression level of FTO protein in smooth muscle was significantly decreased after knockout of Fto gene(P＜0.01).Compared with WT group,the mice in DM group exhibited a significant decrease in body weight and a marked increase in fasting blood glucose level(P＜0.05).There were no noticeable differences in body weight or fasting blood glucose level between FtoSMKO-DM group and DM group(P＞0.05).(3)The contraction responses of aortic smooth muscle in DM group were substantially increased by phenylephrine compared with WT group.Specifically,vaso-constriction responses mediated by non-L-type calcium channels and store-operated calcium channels(SOCC)were signifi-cantly enhanced in DM group.In addition,the responses mediated by inositol 1,4,5-trisphosphate receptors(IP3R),which facilitate calcium release from the sarcoplasmic reticulum,were significantly enhanced.However,the responses mediated by caffeine-activated ryanodine receptors(RyR),which also facilitate calcium release from the sarcoplasmic re-ticulum,were significantly inhibited(P＜0.05).(4)Compared with DM group,the phenylephrine-induced contraction re-sponses of aortic smooth muscle in FtoSMKO-DM group were greatly weakened(P＜0.05).In particular,the vasoconstriction responses mediated by non-L-type calcium channels and SOCC in FtoSMKO-DM group were greatly suppressed(P＜0.05),while those mediated by caffeine-activated RyR were dramatically boosted(P＜0.05).However,IP3R-mediated responses were not affected(P＞0.05).CONCLUSION:Smooth muscle-specific Fto gene knockout suppresses contractile hyperre-sponsiveness in the aortic smooth muscle of DM mice,which may be attributed to involvement of FTO protein in calcium regulation in the vascular smooth muscle.

This study investigated the effects of Xuefu Zhuyu Decoction on myocardial metabolites in a rat model of coronary heart disease with heart blood stasis syndrome and explored the therapeutic mechanism of blood circulation-promoting and blood stasis-removing therapy. SD rats were randomly divided into a sham operation group, a model group, a Xuefu Zhuyu Decoction group(14.04 g·kg~(-1)), and a trimetazidine group(5.4 mg·kg~(-1)). The sham operation group underwent thread insertion without ligation, while the other groups underwent coronary artery left anterior descending branch ligation to induce a model of coronary heart disease with heart blood stasis syndrome. Three days after modeling, drug intervention was performed, and samples were taken after 14 days of intervention. General conditions were observed, and electrocardiogram and cardiac ultrasound indices were measured. Hematoxylin-eosin(HE) staining and Masson staining were used to observe tissue pathological morphology. The enzyme linked immunosorbent assay(ELISA) was used to measure the levels of triglyceride(TG) and total cholesterol(TC) in the serum. Ultra high performance liquid chromatography-quantitative exactive-mass spectrometry(UHPLC-QE-MS) technology was used to screen differential metabolites in myocardial tissue and conduct metabolic pathway enrichment analysis. The results showed that Xuefu Zhuyu Decoction significantly improved the general condition of the model rats, reduced heart rate and ST segment elevation in the electrocardiogram, increased left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS), and decreased left ventricular internal diameter in diastole(LVIDd) and left ventricular internal diameter in systole(LVIDs). HE staining and Masson staining showed that Xuefu Zhuyu Decoction effectively alleviated myocardial tissue structural disorders, inflammatory cell infiltration, and collagen fiber deposition in the model rats. ELISA results showed that Xuefu Zhuyu Decoction effectively regulated serum TG and TC levels in the model rats. There were significant differences in the metabolic phenotypes of myocardial samples in each group. Fourteen differential metabolites were identified in the Xuefu Zhuyu Decoction group, involving five metabolic pathways, including arginine and proline metabolism, glycerophospholipid metabolism, aminoacyl-tRNA biosynthesis, ether lipid metabolism, and alanine, aspartate, and glutamate metabolism. Xuefu Zhuyu Decoction improved cardiac function and myocardial structural damage in the rat model of coronary heart disease with heart blood stasis syndrome, and its biological mechanism involved the regulation of lipid metabolism, choline metabolism, amino acid metabolism, energy metabolism, and protein synthesis pathways.
Rats ; Animals ; Stroke Volume ; Rats, Sprague-Dawley ; Ventricular Function, Left ; Coronary Disease/drug therapy* ; Metabolomics

Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.
Mice ; Animals ; Epilepsy, Temporal Lobe/pathology* ; Parvalbumins/metabolism* ; Parkinson Disease/pathology* ; Neurons/metabolism* ; Interneurons/physiology* ; Disease Models, Animal ; Brain/pathology*

Aim To investigate the mechanism of RhoA/ROCK signaling pathway in abnormal aortic contractility in type 2 diabetes (T2DM) mice. Methods The experiment was divided into two groups, the control group (db/m mice) and the model group (db/db mice). Changes of the response to different methods were measured in aorta rings using a Multi Myograph System. At the same time, the protein expression changes of aortic smooth muscle contraction signaling pathway in mice were determined by Western method. Results Compared with the control group, the blood glucose and body weight levels of the mice in the T2DM group significantly increased, and the cardiac function was abnormal (P <0. 01). The contractile response of the aorta of the diabetic mice induced by the contractile agents Phe, 5-HT and CaCl

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

To investigate the regulation of N6- methyladenosine ( m6A ) modification on L-type calcium channels in atrial myocytes under high hydrostatic pressure, mediated by methyltransferase-like protein 3 ( METTL3 ). Methods C57BL/6J mice were randomly assigned to the control group and the hypertension group ( treated with continuous administration of angiotensin for four weeks ). Masson staining was used to observe the fibrosis of mouse atrial tissue, while dot blot assay and Western blot were used to detect the levels of m6A, METTL3, and Cavi1 2 in the atrial tissue. A high hydrostatic pressure model was constructed using the HL-1 cell line cultured in vitro, and METTL3 was intervened to observe changes in m6A expression levels, METTL3 and Cavi1 2 levels in cells,and action potential duration ( APD ) and L-type calcium current ( I

Ferroptosis， a new type of iron-dependent programmed cell death， is related to multiple pathways such as glutathione/glutathione peroxidase 4， iron metabolism， lipid metabolism， and iron autophagy， and plays an important part in the occurrence and development of many diseases， such as tumor， cerebral ischemia， and Parkinson's disease. Ferroptosis is a double-edged sword as it can eliminate pathological cells （such as tumor cells） but long-term ferroptosis may cause or aggravate other disorders related to abnormal lipid metabolism and iron metabolism. Regulating the balance between cell proliferation and ferroptosis may be an important target for drug intervention in diseases. The Yin-yang theory is one of the foundational principles of traditional Chinese medicine （TCM）， which is used to explain the physiological functions and pathological changes of human body and to guide the diagnosis and prevention of disease and health care. The balance of cell proliferation and programmed death is essentially the balance of Yin and Yang at the cellular level， which is governed and regulated by the law of balance. TCM intervenes in ferroptosis by promoting ferroptosis of tumor cells （damaging the excess） and inhibiting ferroptosis of other diseases （compensating the deficiency）， which is similar to the treatment principle of adjusting Yin and Yang. On this basis， this article aims to use the Yin-yang theory to clarify the relationship between TCM promoting ferroptosis and inhibiting ferroptosis， which is expected to lay a basis for the modern application of Yin-yang theory and provide new targets for TCM treatment.

This study was designed to identify the pathogen causing soft rot of Pinellia ternata in Qianjiang of Hubei province and screen out the effective bactericides, so as to provide a theoretical basis for the control of soft rot of P. ternata. In this study, the pathogen was identified based on molecular biology and physiological biochemistry, followed by the detection of pathogenicity and pathogenicity spectrum via plant tissue inoculation in vitro and the indoor toxicity determination using the inhibition zone method to screen out bactericide with good antibacterial effects. The control effect of the bactericide against P. ternata soft rot was verified by the leave and tuber inoculation in vitro. The phylogenetic tree was constructed based on the 16 S rDNA, dnaX gene, and recA gene sequences, respectively, and the result showed that the pathogen belonged to the same branch as the type strain Dickeya fangzhongdai JS5. The physiological and biochemical tests showed that the pathogen was identical to D. fangzhongdai, which proved that the pathogen was D. fangzhongdai. The pathogenicity test indicated that the pathogen could obviously infect leaves at 24 h and tubers in 3 d. As revealed by the indoor toxicity test, 0.3% tetramycin, 5% allicin, and 80% ethylicin had good antibacterial activities, with EC_(50) values all less than 50 mg·L~(-1). Tests in tissues in vitro showed that 5% allicin exhibited the best control effect, followed by 0.3% tetramycin and 10% zhongshengmycin oligosaccharide, and their preventive effects were better than curative effects. Therefore, 5% allicin can be used as the preferred agent for the control of P. ternata soft rot, and 0.3% tetramycin and 10% zhongshengmycin oligosaccharide as the alternatives. This study has provided a certain theoretical basis for the control of P. ternata soft rot.
Phylogeny ; Pinellia/chemistry* ; Plant Leaves ; Plant Tubers