Use of ogn overexpression vector preparation for reperfusion arrhythmia preventive drug

Abstract

The application relates to application of an OGN overexpression vector in preparation of a reperfusion arrhythmia prevention drug and belongs to the technical field of medicines. In order to solve the problem that the existing anti-arrhythmia drugs cannot effectively prevent reperfusion arrhythmia, the application provides application of an OGN overexpression vector in preparation of a reperfusion arrhythmia prevention drug, the OGN overexpression vector is a recombinant adeno-associated virus vector, and the OGN overexpression vector contains a nucleotide sequence coding OGN. The application constructs a recombinant adeno-associated virus vector carrying an OGN gene, drives efficient expression of the OGN gene in myocardial cells, up-regulates the expression level of Nav1.5 protein, increases the peak value of sodium current, thereby maintaining the normal rhythm of cardiac electrophysiological activity, and realizes targeted improvement of the function of the sodium ion channel of the myocardial cells and the stability of the cardiac electrical conduction. The time window design of the prevention drug of the application is highly consistent with the clinical diagnosis and treatment process, and the prevention drug has strong operability and clinical transformation potential.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical technology, and in particular relates to the application of OGN overexpression vector in the preparation of drugs for the prevention of reperfusion arrhythmias. Background Technology

[0002] Myocardial ischemia-reperfusion is a crucial measure for restoring blood flow to ischemic myocardium. However, the reperfusion process itself can induce severe electrophysiological disturbances, even malignant arrhythmias, mainly manifested as ventricular tachycardia and ventricular fibrillation, accounting for more than 80% of malignant arrhythmias after reperfusion following acute myocardial infarction. Its pathogenesis is closely related to sodium ion channel dysfunction and abnormal cardiac electrical conduction. ATP depletion during ischemia leads to sodium... + / K + Pump inhibition triggers intracellular Na+ + and Ca 2+ Overload, in turn, triggers aberrant electrical activity through delayed afterdepolarization (DADs). During reperfusion, a burst of reactive oxygen species can oxidize Nav1.5 channels, reducing their conductivity and slowing conduction.

[0003] Currently used antiarrhythmic drugs in clinical practice, such as sodium channel blockers (lidocaine), beta-blockers (metoprolol), and potassium channel blockers (amiodarone), have limited efficacy in preventing reperfusion arrhythmias. While sodium channel blockers can inhibit abnormal conduction, they may exacerbate conduction block in ischemic areas; amiodarone, although prolonging action potential duration (APD), cannot reverse Nav1.5 damage caused by oxidative stress. Furthermore, most drugs do not take effect rapidly in the early stages of reperfusion, missing the golden window for intervention. Therefore, there is an urgent need to explore novel regulatory targets at the molecular level.

[0004] Osteoglycin (OGN), a member of the leucine-rich small proteoglycan family, exhibits high expression in cardiac tissue, particularly involved in the regulation of left ventricular development and compensatory hypertrophy. Although the regulatory role of OGN in cardiovascular diseases such as heart failure and ventricular remodeling has been preliminarily verified, its functional role in reperfusion arrhythmias remains a blank area, and there are currently no studies applying it to the prevention of reperfusion arrhythmias. Summary of the Invention

[0005] To address the problem that existing antiarrhythmic drugs cannot effectively prevent reperfusion arrhythmias, this invention provides an application for preparing reperfusion arrhythmia prevention drugs using OGN overexpression vectors.

[0006] The technical solution of the present invention:

[0007] Application of OGN overexpression vector in the preparation of drugs for the prevention of reperfusion arrhythmia.

[0008] Furthermore, the OGN overexpression vector is a recombinant adeno-associated virus vector containing a nucleotide sequence encoding OGN and a myocardial-specific promoter.

[0009] Furthermore, the nucleotide sequence encoding OGN is shown in SEQ ID NO. 1.

[0010] Furthermore, the myocardial-specific promoter is the cardiac troponin T promoter.

[0011] Furthermore, the serotype of the recombinant adeno-associated virus vector is AAV9.

[0012] Furthermore, the OGN overexpression vector is an adeno-associated virus vector AAV9-OGN that overexpresses the OGN gene.

[0013] Furthermore, the reperfusion myocardial injury prophylaxis drug is administered 3 weeks prior to revascularization surgery.

[0014] Furthermore, the preventive medicine has at least one of the following uses:

[0015] (1) Reduce the duration of myocardial ischemia-reperfusion arrhythmias;

[0016] (2) Upregulate Nav1.5 expression, increase Peak value;

[0017] (3) Improve the stability of cardiac electrical conduction.

[0018] The beneficial effects of this invention are:

[0019] The adeno-associated virus (AAV) vector-mediated OGN overexpression vector provided by this invention, driven by a myocardial-specific promoter, can precisely target myocardial tissue and achieve stable OGN expression. Experiments have demonstrated that OGN overexpression mediated by the recombinant viral vector significantly upregulates Nav1.5 sodium channel protein levels, enhances peak sodium current in cardiomyocytes, thereby maintaining the normal rhythm of cardiac electrophysiological activity. In an ischemia-reperfusion model, the action potential dispersion of cardiomyocytes in the OGN overexpression group was significantly reduced, and the conduction velocity was significantly improved, effectively preventing the occurrence of reperfusion arrhythmias.

[0020] Compared to traditional antiarrhythmic drugs, this carrier drug has the advantages of strong targeting and a clear mechanism of action. It repairs sodium ion channel function rather than simply inhibiting ion flow, thus avoiding interference with normal myocardial electrical activity. Furthermore, the drug's 24-72 hour preoperative administration window allows for early upregulation of OGN expression before reperfusion injury occurs, establishing a protective preconditioning effect for cardiomyocytes. This provides a new and effective strategy for the clinical prevention of reperfusion arrhythmias, possessing significant clinical translational value and broad application prospects, and is expected to become an important option for perioperative cardiac protection in cardiovascular surgery. Attached Figure Description

[0021] Figure 1 The electrocardiograms of mice in the sham-operated group and the IR group before and after reperfusion in Example 1 are shown.

[0022] Figure 2 This is a comparison of the Western Blot results of OGN in the myocardial tissue of mice in the sham-operated group and the IR group in Example 1;

[0023] Figure 3 This is a comparison of OGN protein expression levels in the myocardial tissue of mice in the sham-operated group and the IR group in Example 1.

[0024] Figure 4 This is a comparison of OGN mRNA expression levels in the myocardial tissue of mice in the sham-operated group and the IR group in Example 1;

[0025] Figure 5 Echocardiograms of the four groups of mice in Example 2;

[0026] Figure 6 This is a comparison chart of cardiac ejection fraction and fractional shortening of four groups of mice in Example 2. A represents ejection fraction, and B represents fractional shortening of the short axis.

[0027] Figure 7 This is a comparison of the left ventricular end-diastolic diameter and left ventricular end-systolic diameter in four groups of mice in Example 2. A is the left ventricular end-diastolic diameter, and B is the left ventricular end-systolic diameter.

[0028] Figure 8 The electrocardiograms of the three groups of mice in Example 3 are shown.

[0029] Figure 9 This is a comparison of the time course of arrhythmia induction in the three groups of mice in Example 3;

[0030] Figure 10 This is a comparison chart of the incidence of cardiac arrhythmia in the three groups of mice in Example 3;

[0031] Figure 11This is a comparison of Western blot bands of Nav1.5 protein in four groups of mouse cardiomyocytes in Example 3.

[0032] Figure 12 This is a comparison of the protein expression levels of Nav1.5 in four groups of mouse cardiomyocytes in Example 3;

[0033] Figure 13 The four groups of mouse cardiomyocytes in Example 4 Current density representation diagram;

[0034] Figure 14 Four groups of mouse cardiomyocytes in Example 4 Current density statistical comparison chart;

[0035] Figure 15 Four groups of mouse cardiomyocytes in Example 4 Statistical comparison chart of peak current density;

[0036] Figure 16 The standardized conductance (G / G ratio) of the four groups of mouse cardiomyocytes in Example 4 max Data comparison chart;

[0037] Figure 17 This is a comparison of sodium ion channel inactivation curves in four groups of mouse cardiomyocytes in Example 4;

[0038] Figure 18 This is a comparison of sodium ion channel activation curves in four groups of mouse cardiomyocytes in Example 4;

[0039] Figure 19 This is an isochronous plot of electrical conduction in four groups of mouse cardiomyocytes in Example 5;

[0040] Figure 20 This is a comparison of the electrical conduction velocities of four groups of mouse cardiomyocytes in Example 5;

[0041] Figure 21 The diagram shows the changes in action potentials of four groups of mouse cardiomyocytes in Example 5. A is a representative action potential graph, and B is a statistical graph of action potential peak values.

[0042] Figure 22 This is a comparison diagram of the conduction velocity of the rising branch of the action potential in four groups of mouse cardiomyocytes in Example 5;

[0043] Figure 23 This is a graph showing the action potential changes in four groups of mouse cardiomyocytes in Example 5. A represents the action potential (APD) changes. 90 B is ADP 30 ;

[0044] Figure 24This is a statistical graph of the action potential time history of four groups of mouse cardiomyocytes in Example 5. A represents the action potential time history of action potentials. 90 B is ADP 30 . Detailed Implementation

[0045] The technical solution of the present invention will be further described below with reference to embodiments, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention. In the following embodiments, the process equipment or apparatus not specifically specified are all conventional equipment or apparatus in the art. Unless otherwise specified, the raw materials used in the embodiments of the present invention are all commercially available; unless otherwise specified, the technical means used in the embodiments of the present invention are all conventional means well known to those skilled in the art.

[0046] Example 1

[0047] This embodiment demonstrates, through mouse experiments, that OGN expression is reduced in myocardial tissue after myocardial ischemia-reperfusion.

[0048] I. Methods for grouping experimental animals and establishing experimental models:

[0049] Eight-week-old male C57BL / 6J mice (weighing 22-25g) were randomly divided into two groups:

[0050] (1) Sham group: only open-chest surgery and suture threading were performed, without ligation of the coronary arteries;

[0051] (2) Ischemia-reperfusion (IR) group: Blood flow was restored 30 minutes after ligation of the left anterior descending coronary artery, and reperfusion was performed for 48 hours.

[0052] Surface electrocardiograms were monitored in the Sham and IR groups before and after reperfusion, and the results are as follows: Figure 1 As shown, the ST segment immediately after ligation arched upwards, and after reperfusion, the ST segment decreased by ≥50%, indicating that the IR group model was successfully constructed.

[0053] 2. Mice in the Sham group were sacrificed 48 hours after surgery and mice in the IR group were reperfused 48 hours after surgery. The heart was quickly removed, the left ventricular myocardium was separated along the interventricular septum, and the right ventricle and atrium were excised on ice. The expression of OGN in the myocardial tissue was detected.

[0054] (1) Western Blot detection:

[0055] 1. Protein extraction: Homogenize left ventricular myocardial tissue with RIPA lysis buffer (containing PMSF), centrifuge at 13500 rpm for 15 minutes, and collect the supernatant;

[0056] 2. Electrophoretic transfer: Proteins were separated by 10% SDS-PAGE and transferred to an NC membrane;

[0057] 3. Antibody incubation: anti-OGN antibody (1:1000, Proteintech), anti-β-actin antibody (1:3000, CST).

[0058] 4. Results Analysis: Image J quantifies gray values, and the OGN / β-actin ratio represents the relative expression level.

[0059] The results are as follows Figure 2 and Figure 3 As shown, compared with the Sham group, the content of OGN protein in the myocardial tissue of IR group mice was significantly reduced (P<0.001).

[0060] (2) qRT-PCR detection:

[0061] 1. RNA extraction: Total RNA was extracted from the left ventricle using the Trizol method and quantified using NanoDrop.

[0062] 2. Reverse transcription: 1 μg of RNA was used to synthesize cDNA using the PrimeScript RT kit;

[0063] 3. Quantitative PCR: SYBR Green assay for OGN mRNA detection.

[0064] 4. Results Analysis: 2 -ΔΔCt The relative expression level is calculated using this method.

[0065] The results are as follows Figure 4 As shown, the qRT-PCR results were consistent with the Western Blot results, and the OGN content in the myocardial tissue of IR group mice was significantly reduced (P<0.001).

[0066] The experimental results of this embodiment show that OGN expression is reduced in myocardial tissue after myocardial ischemia-reperfusion injury.

[0067] Example 2

[0068] This embodiment demonstrates that overexpression of OGN can improve cardiac function after ischemia-reperfusion.

[0069] I. Construction of overexpression vectors

[0070] (1) Carrier selection:

[0071] The adeno-associated virus type 9 (AAV9) vector system was selected, with a vector backbone of ssAAV-cTnT-OGN-SV40pA, containing the following elements: cardiac troponin T (cTnT) promoter, the target gene OGN coding sequence, and SV40pA, which helps improve expression efficiency and stability. The nucleotide sequence encoding OGN is shown in SEQ ID NO.1.

[0072] (2) OGN gene cloning and viral packaging

[0073] OGN gene cloning and viral packaging were performed by Guangzhou Aizhe Biotechnology Co., Ltd. using a gene cloning-virus packaging-purification and concentration method, yielding purified AAV9-OGN virus particles with a titer of 1×10⁻⁶. 13 vg / mL.

[0074] (3) Control vector

[0075] The OGN sequence was replaced with a meaningless sequence, while the remaining elements were completely identical to AAV9-OGN. The process was completed by Guangzhou Aizhe Biotechnology Co., Ltd. using a gene cloning-virus packaging-purification and concentration method to obtain purified AAV9-NC virus particles with a titer of 1×10⁻⁶. 13 vg / mL.

[0076] II. Animal Experiment Grouping and Model Establishment Methods:

[0077] Eight-week-old male C57BL / 6J mice (weighing 22-25g) were randomly divided into four groups:

[0078] (1) Sham group: The same amount of normal saline was injected into the tail vein, and the left anterior descending coronary artery was opened but not ligated;

[0079] (2) IR group: The same amount of normal saline was injected into the tail vein. After 4 weeks, the left anterior descending coronary artery was ligated for 30 minutes and blood flow was restored. The reperfusion lasted for 48 hours.

[0080] (3) OGN-IR group: AAV9-OGN (100μL, 1×10¹¹vg) was injected into the tail vein. After 4 weeks, blood flow was restored 30 minutes after ligation of the left anterior descending coronary artery, and then reperfused for 48 hours.

[0081] (4) NC-IR group: AAV9-NC (100μL, 1×10¹¹vg) was injected into the tail vein. After 4 weeks, blood flow was restored 30 minutes after ligation of the left anterior descending coronary artery, and then reperfused for 48 hours.

[0082] 3. Monitor cardiac function through echocardiography.

[0083] Echocardiograms of the four groups of mice are as follows: Figure 5 As shown in the figure, the cardiac ejection fraction (EF) comparison chart is as follows: Figure 6 As shown in Figure A, the comparison chart of shortened fraction FS is as follows. Figure 6 As shown in Figure B, the comparison diagram of left ventricular end-diastolic diameter (LVIDd) is as follows: Figure 7 As shown in Figure A, the comparison diagram of left ventricular end-systolic diameters (LVIDs) is as follows: Figure 7As shown in Figure B, compared with the Sham group, the IR group mice showed weakened ventricular wall motion, with significantly reduced EF% and FS%, indicating that ischemia-reperfusion caused weakened cardiac function in mice. In contrast, the OGN-IR group mice showed improved ventricular wall motion, with significantly increased EF% and FS%, which was statistically different from the NC-IR group (P<0.001). No significant changes were observed in LVIDd and LVIDs.

[0084] This result demonstrates that OGN overexpression mediated by the AAV9 vector can significantly reverse cardiac systolic dysfunction caused by myocardial ischemia-reperfusion, providing direct functional evidence for its application as a preventive drug.

[0085] Example 3

[0086] This embodiment demonstrates that overexpression of OGN can reduce the incidence of arrhythmias after ischemia-reperfusion.

[0087] I. Grouping of Experimental Animals

[0088] Eight-week-old male C57BL / 6J mice (weighing 22-25g) were randomly divided into three groups:

[0089] (1) Sham group: The tail vein was injected with an equal amount of physiological saline. After four weeks of feeding, the chest was opened but the left anterior descending coronary artery was not ligated.

[0090] (2) OGN-IR group: AAV9-OGN (100μL, 1×10¹¹vg) was injected into the tail vein. After 4 weeks, blood flow was restored 30 minutes after ligation of the left anterior descending coronary artery, and then reperfused for 48 hours.

[0091] (3) NC-IR group: AAV9-NC (100μL, 1×10¹¹vg) was injected into the tail vein. After 4 weeks, blood flow was restored 30 minutes after ligation of the left anterior descending coronary artery, and then reperfused for 48 hours.

[0092] II. Detection of arrhythmias using programmed electrical stimulation.

[0093] Forty-eight hours post-surgery in the Sham group, and forty-eight hours after reperfusion in the OGN-IR and NC-IR groups, mice underwent an arrhythmia-inducing experiments using electrical stimulation. Mice were re-anesthetized, fixed on the operating table, and reconnected to a small animal ventilator. Electrocardiograms (ECGs) were continuously recorded using an ECG monitoring system. Specialized electrode needles were inserted into the right ventricle of the mice for electrical stimulation. The stimulation mode used was 10 consecutive electrical pulses (S1) with a coupling interval of 80 ms, followed by two additional stimuli (S2 and S3) at 80 and 78 ms respectively, with a coupling interval of 2 ms, decreasing in step size of -2. Arrhythmia occurrence was recorded at three voltages: 3.5V, 5V, and 8V. The waveform was adjusted, and the stimulation program was initiated, thus inducing ventricular arrhythmias. The stimulation was repeated twice to check the reproducibility of the experiment.

[0094] The changes in the mouse electrocardiogram during and for a period of time after electrical stimulation are as follows: Figure 8 As shown, the duration and incidence of arrhythmia induction are as follows: Figure 9 and Figure 10 As shown, compared with the Sham group, the duration of arrhythmia in the NC-IR group was significantly prolonged, while OGN-IR treatment significantly reversed the prolongation of arrhythmia duration and the increase in the incidence of arrhythmia.

[0095] This result indicates that OGN overexpression can reduce the incidence and duration of arrhythmias in IR mice, effectively reducing the risk of arrhythmias after ischemia-reperfusion, and verifying its positive role in preventing reperfusion arrhythmias.

[0096] Example 4

[0097] This embodiment demonstrates that overexpression of OGN inhibits the occurrence of arrhythmias after ischemia-reperfusion by regulating the activity of sodium ion channels in cardiomyocytes.

[0098] Nav1.5 is a core subunit of the cardiac voltage-gated sodium channel, and its abnormal expression is closely related to arrhythmias. This embodiment aims to clarify the mechanism by which OGN affects the electrophysiological properties of cardiomyocytes by detecting Nav1.5 expression and current changes. Based on the animal experiment grouping and model establishment in Example 2, mice in each group were sacrificed after 48 hours of reperfusion, and their hearts were quickly removed. Left ventricular myocardial tissue was taken and divided into several aliquots for Western blotting and qRT-PCR to detect changes in Nav1.5 expression, and whole-cell patch-clamp experiments to detect changes in sodium ion current density. .

[0099] I. Western Blot Experiment

[0100] 1. Protein extraction: Homogenize left ventricular myocardial tissue with RIPA lysis buffer (containing PMSF), centrifuge at 13500 rpm for 15 minutes, and collect the supernatant;

[0101] 2. Electrophoretic transfer: Proteins were separated by 7.5% SDS-PAGE and transferred onto a PVDF membrane;

[0102] 3. Antibody incubation: Nav1.5 primary antibody (1:1000, Alomone Labs #ASC-005), HRP secondary antibody (1:5000, anti-rabbit IgG).

[0103] 4. Results Analysis: Image J quantifies grayscale values, and the Nav1.5 / HRP ratio represents the relative expression level.

[0104] Western blot bands of Nav1.5 protein in four groups of mouse cardiomyocytes are shown below. Figure 11 As shown, the expression level of Nav1.5 protein is as follows: Figure 12 As shown, compared with the Sham group, the expression level of Nav1.5 protein in the IR group mice was significantly reduced, while the expression level of Nav1.5 protein was significantly increased after OGN-IR treatment.

[0105] II. Whole-cell patch-clamp experiment

[0106] Cardiomyocytes were placed in a bath, and a prepared extracellular solution (containing mmol / L: NaCl 135, KCl 5.4, CaCl2 1.8, MgCl2 1, HEPES 10, glucose 10, pH adjusted to 7.4 with NaOH) was added. A glass microelectrode was fabricated, and then the electrode internal solution used to record the sodium current (containing mmol / L: CsCl 120, MgCl2 1, CaCl2 1, EGTA 10, HEPES 10, Na2ATP 5, pH adjusted to 7.2 with CsOH) was poured in until two-thirds of the electrode was filled. The electrode was then connected to the probe of a patch-clamp instrument. Cell state was observed under an inverted microscope. The electrode was gently moved to slightly contact the cell membrane surface, and a suitable negative pressure of -10 mmHg was applied to seal the cells. A high-resistance seal was formed when the displayed resistance reached 1 GΩ. At this point, a negative pressure of -50 mmHg was applied via aspiration to rupture the membrane. After rupture, an appropriate stimulation program was selected, starting from -90 mV and increasing in 5 mV steps to +30 mV. Recording was performed from 0 ms to 400 ms. The clamping voltage was set to -40 mV. The membrane capacitance of each cell was recorded and analyzed. Current density (pA / pF) = current intensity / membrane capacitance.

[0107] Four groups of mouse cardiomyocytes Current density for example Figure 13 and Figure 14As shown, the peak current density is as follows Figure 15 As shown, compared with the Sham group, the IR group mice Significantly reduced, OGN-IR group Increased; compared with the Sham group, the peak value of IR group mice was higher. Significantly reduced, peak value of OGN-IR group Increase.

[0108] Four groups of mouse cardiomyocyte standardized conductance (G / Gmax) data compared to, for example Figure 16 As shown, the inactivation and activation curves of sodium ion channels are compared, for example... Figure 17 and Figure 18 As shown, the results indicate that the voltage-dependent steady-state activation, inactivation, and reactivation of Na ion channels were not altered by OGN overexpression.

[0109] This result indicates that OGN overexpression can increase sodium ion current density in cardiomyocytes by upregulating Nav1.5 protein expression and enhancing protein function. It effectively reverses the electrophysiological abnormalities caused by ischemia-reperfusion, stabilizes the action potential of myocardial cells, and thus inhibits the occurrence of arrhythmias, providing direct electrophysiological evidence for its role in preventing reperfusion arrhythmias.

[0110] Example 5

[0111] This embodiment demonstrates that overexpression of OGN can improve cardiac electrical conduction after ischemia-reperfusion.

[0112] This embodiment uses optical mapping of the myocardium to detect changes in cardiac electrical conduction after overexpression of OGN in vivo. Based on the animal experimental grouping and model establishment in Example 2, mice in each group were sacrificed after 48 hours of reperfusion. Hearts were quickly removed, and left ventricular myocardial tissue was taken and divided into several portions for optical mapping detection. Under light-protected conditions, the myocardial tissue was immersed in RH237 dye solution for 15-20 minutes, rinsed with dye-free Tyrode solution to remove residual dye, and Blebbistatin (10 μM) was added to the perfusion fluid to completely inhibit myocardial contraction. Images were then acquired using an optical system.

[0113] Isochron diagrams of four groups of mouse cardiomyocytes are shown below. Figure 19 As shown, the conduction velocity is as follows Figure 20 As shown, the electrical signal conduction in the myocardial tissue of the Sham group was uniform and orderly, while the electrical signal conduction in the myocardial tissue of the IR group was significantly disordered, with conduction delay in local areas and a significantly slower conduction velocity. In contrast, the degree of disorder in the electrical signal conduction in the myocardial tissue of the OGN-IR group was significantly reduced compared to the IR group, and the conduction velocity was significantly faster than that of the IR group, approaching the level of the Sham group.

[0114] The maximum fluorescence intensity of myocardial cells in the four groups of mice was as follows: Figure 21 As shown, compared with the Sham group, the maximum fluorescence intensity of cardiomyocytes in the IR group was significantly decreased (P<0.05); while the maximum fluorescence intensity in the OGN-IR group was significantly increased compared with the IR group. The conduction velocity of the rising branch of the action potential in the cardiomyocytes of the four groups of mice is shown in the figure below. Figure 22 As shown, compared with the Sham group, the conduction velocity of the rising branch of the action potential in the IR group was significantly slower; the conduction velocity of the rising branch of the action potential in the OGN-IR group was significantly faster than that in the IR group.

[0115] The action potential amplitude diagrams of four groups of mouse myocardial cells are shown below. Figure 23 As shown, APD 90 and APD 30 like Figure 24 As shown, compared with the Sham group, the IR group mice had significantly reduced action potential amplitude and APD. 90 and APD 30 The action potential amplitude was significantly prolonged in the OGN-IR group compared to the IR group, while the APD was significantly increased. 90 and APD 30 The time to cardiac arrest (APD) was significantly shorter than in the IR group, approaching the level of the Sham group. Specifically, OGN overexpression significantly shortened the APD in the ventricles of mice after IR. 90 and APD 30 The extension.

[0116] This result indicates that ischemia-reperfusion injury can lead to disordered and slowed conduction of myocardial electrical signals. OGN overexpression can effectively improve the disordered electrical conduction of myocardial tissue after ischemia-reperfusion, shorten the duration of action potentials, increase the amplitude of action potentials, and restore the stability of action potential duration, thereby further stabilizing the electrophysiological state of myocardium and reducing the substrate for reentrant arrhythmias caused by electrical conduction disorders, further supporting its role in preventing reperfusion arrhythmias.

Claims

1. The application of OGN overexpression vector in the preparation of drugs for the prevention of reperfusion arrhythmias, characterized in that, The reperfusion arrhythmia is an arrhythmia caused by myocardial ischemia-reperfusion injury, and the nucleotide sequence encoding OGN is shown in SEQ ID NO.

1.

2. The application according to claim 1, characterized in that, The OGN overexpression vector is a recombinant adeno-associated virus vector containing a nucleotide sequence encoding OGN and a myocardial-specific promoter.

3. The application according to claim 2, characterized in that, The myocardial-specific promoter is the cardiac troponin T promoter.

4. The application according to claim 3, characterized in that, The serotype of the recombinant adeno-associated virus vector is AAV9.

5. The application according to claim 4, characterized in that, The OGN overexpression vector is an adeno-associated virus vector AAV9-OGN that overexpresses the OGN gene.

6. The application according to any one of claims 1-5, characterized in that, The preventive medicine has at least one of the following uses: (1) Reduce the duration of myocardial ischemia-reperfusion arrhythmias; (2) Upregulate Nav1.5 expression and increase I Na Peak value; (3) Improve the stability of cardiac electrical conduction.

Images