Application of pinoresinol diglucoside in preparation of medicine for treating chronic pain

Abstract

The invention belongs to the field of medical chemistry, and discloses application of pinoresinol diglucoside in preparation of a medicine for treating chronic pain. In the application, pinoresinol diglucoside can obviously relieve mechanical pain hypersensitivity and acupuncture hyperalgesia induced by sciatic nerve injury, and can obviously relieve mechanical pain hypersensitivity induced by ischemia reperfusion after a single-side ankle joint is pressed by a rubber ring; the function of tetrodotoxin sensitive voltage-gated sodium ion channels on dorsal root ganglion neurons can be remarkably inhibited, and the peak current density is remarkably reduced. According to in-vivo experiments, a small molecule compound terpineol diglucoside is adopted to play a remarkable analgesic role on two chronic pain animal models, and cell experiments confirm that the analgesic mechanism is mediated by inhibiting tetrodotoxin sensitive voltage-gated sodium ion channels on dorsal root ganglion neurons; a theoretical basis can be provided for preparing a medicine for treating chronic pain by taking pinoresinol diglucoside as a main component.

Description

Technical Field

[0001] The present invention relates to the technical field of pharmaceutical chemistry, and in particular to use of pinesterol diglucoside in preparing a medicine for treating chronic pain. Background Art

[0002] Chronic pain is an intractable painful disease that lasts for more than three months. Global statistics show that the incidence of chronic pain is as high as 8.7% to 42%. There are more than 300 million chronic pain patients in China, and the number is increasing at a rate of 20 million per year. Its symptoms include chronic local tingling, numbness, cold, tenderness and diffuse pain, which have long-term effects on patients' sleep, diet, work and mental health, and seriously reduce their quality of life. The causes of chronic pain are complex and the related mechanisms are unclear, resulting in the lack of effective prevention and treatment methods for this type of pathological pain, which has caused great distress to patients. Therefore, exploring the mechanism of occurrence and development of chronic pain and finding new targeted analgesics that effectively prevent and treat chronic pain are current problems that need to be solved in the field of pain research.

[0003] Pinoresinol diglucoside (PDG) is a lignin compound widely distributed in the plant kingdom. It is also one of the main active ingredients isolated from the traditional Chinese medicine Eucommia ulmoides. It has multiple biological activities and pharmacological effects such as anti-inflammatory, antioxidant, and neuroprotective. Studies have shown that PDG can inhibit the release of proinflammatory factors (tumor necrosis factor α, interleukin 1β), reactive oxygen species, and malondialdehyde, and increase the activity of antioxidant enzymes (superoxide dismutase and catalase). PDG can also upregulate the ratio of Bcl-2 / Bax and downregulate the expression of cytochrome c and cleaved caspase-3, thereby inhibiting neuronal apoptosis. However, there are no literature reports on the analgesic effect of PDG on chronic pain, especially neuropathic pain. Developing PDG into a new analgesic drug for the treatment of chronic pain has extremely high potential value and social significance.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a use of pinesterol diglucoside in the preparation of a drug for treating chronic pain, aiming to solve the problem that analgesics for the treatment of chronic pain in the prior art are poorly effective and there is a lack of new targeted analgesics that are effective in preventing and treating chronic pain.

[0006] The technical solution of the present invention is as follows:

[0007] The invention provides use of pinesterol diglucoside in preparing a medicine for treating chronic pain.

[0008] Optionally, in the use of pinesterol diglucoside, the chronic pain is neuropathic pain or chronic post-ischemic pain.

[0009] Optionally, in the use of pinesterol diglucoside, the neuropathic pain is chronic pain induced by unilateral partial sciatic nerve injury.

[0010] Optionally, in the use of pinesterol diglucoside, the neuropathic pain is mechanical allodynia and needle hyperalgesia induced by unilateral partial sciatic nerve injury.

[0011] Optionally, in the use of the pinesterol diglucoside, the chronic post-ischemic pain is chronic pain induced by ischemia-reperfusion after compression of a unilateral ankle joint by a rubber ring.

[0012] Optionally, in the use of pinesterol diglucoside, the chronic post-ischemic pain is mechanical allodynia induced by ischemia-reperfusion after compression of a unilateral ankle joint by a rubber ring.

[0013] Optionally, in the use of the pinesterol diglucoside, the dosage form of the drug is an injection form permitted in pharmaceutical science.

[0014] Optionally, in the use of the pinoresinol diglucoside, the pinoresinol diglucoside is the only active ingredient of the drug.

[0015] Optionally, in the use of the pine ester alcohol diglucoside, the single application dose of the pine ester alcohol diglucoside is 5 mg / kg.

[0016] In the use of the pinesterol diglucoside, the drug treats the chronic pain by inhibiting the function of tetrodotoxin (TTX)-sensitive voltage-gated sodium channel (NaV) on dorsal root ganglion (DRG) neurons.

[0017] The use of a pine ester alcohol diglucoside provided by the present invention in preparing a drug for treating chronic pain has the following beneficial effects:

[0018] (1) Pinesterol diglucoside can significantly alleviate mechanical allodynia and acupuncture hyperalgesia induced by sciatic nerve injury.

[0019] (2) Pinesterol diglucoside can significantly alleviate the mechanical allodynia induced by ischemia-reperfusion after unilateral ankle joint compression by rubber ring.

[0020] (3) Pinesterol diglucoside can significantly inhibit the function of tetrodotoxin-sensitive voltage-gated sodium channels in dorsal root ganglion neurons, which is manifested by a significant decrease in peak current density.

[0021] The present invention innovatively uses a small molecule compound, pinesterol diglucoside, to exert a significant analgesic effect on two chronic pain animal models through in vivo experiments, and through cell experiments it is clarified that its analgesic mechanism is mediated by inhibiting tetrodotoxin-sensitive voltage-gated sodium ion channels on dorsal root ganglion neurons, thus providing a theoretical basis for preparing a therapeutic drug for chronic pain using pinesterol diglucoside as the main ingredient. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The figure is the effect of pinesterol diglucoside on the mechanical allodynia symptoms of rats with partial sciatic nerve injury in the examples of the present invention, wherein BL: Baseline; dpi: Day post injury; SNI: Spared nerve injury; ip: Intraperitoneal injection; compared with the control group: * P<0.05 (mean±SE, n=6).

[0023] Figure 2 The graph is a graph showing the effect of pinesterol diglucoside on the symptoms of acupuncture hyperalgesia in rats with partial sciatic nerve injury in the examples of the present invention, wherein BL: Baseline; dpi: Day post injury; SNI: Spared nerve injury; ip: Intraperitoneal injection; compared with the control group: * P<0.05 (mean±SE, n=6).

[0024] Figure 3 This is a graph showing the acetone cold stimulation response of pinesterol diglucoside to rats with partial sciatic nerve injury in an example of the present invention, wherein, BL: Baseline; dpi: Day post injury; SNI: Spared nerve injury; ip: Intraperitoneal injection; compared with the control group: P ≥ 0.05 (mean ± standard error, n = 6).

[0025] Figure 4The figure is the effect of pinesterol diglucoside on the mechanical allodynia symptoms of rats with ischemia-reperfusion after ankle joint compression by rubber ring in the embodiment of the present invention, wherein, BL: Baseline; dpi: Day post injury; CPIP: Chronic post-ischemia pain; ip: Intraperitoneal injection; compared with the control group: * P<0.05 (mean±SE, n=4).

[0026] Figure 5 This is a graph showing the effect of pinesterol diglucoside on the symptoms of acupuncture hyperalgesia in rats with ischemia-reperfusion after ankle joint compression by a rubber ring in an example of the present invention, wherein, BL: Baseline; dpi: Day post injury; CPIP: Chronic post-ischemia pain; ip: Intraperitoneal injection; compared with the control group: P≥0.05 (mean±standard error, n=4).

[0027] Figure 6 This is a graph showing the acetone cold stimulation response of pinesterol diglucoside to ischemia-reperfusion in rats with ankle joint compression by rubber ring in an example of the present invention, wherein, BL: Baseline; dpi: Day post injury; CPIP: Chronic post-ischemia pain; ip: Intraperitoneal injection; compared with the control group: P≥0.05 (mean±standard error, n=4).

[0028] Figure 7 The figure is the effect of pinesterol diglucoside on the voltage-gated sodium channel function of primary cultured dorsal root ganglion neurons of rats in the embodiment of the present invention, wherein IV: current voltage; NaV: voltage-gated sodium channel, voltage-gated sodium channel; compared with the control group: * P<0.05 (mean±SE, control group n=10, PDG group n=12).

[0029] Figure 8The figure is the effect of pinesterol diglucoside on the function of tetrodotoxin-insensitive voltage-gated sodium channel of primary cultured dorsal root ganglion neurons of rats in the embodiment of the present invention, wherein IV: current voltage; NaV: voltage-gated sodium channel, voltage-gated sodium channel; TTX: Tetrodotoxin, tetrodotoxin; TTX-sensitive NaV current is compared with the control group: * P<0.05 (mean ± standard error, control group n = 10, PDG group n = 12); TTX-insensitive NaV current compared with the control group: n.s. P≥0.05 (mean±SE, control group n=12, PDG group n=10). DETAILED DESCRIPTION

[0030] The present invention provides a use of pinesterol diglucoside in the preparation of a drug for treating chronic pain. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] The embodiment of the present invention provides a use of pinesterol diglucoside in preparing a medicine for treating chronic pain.

[0033] The present invention studies the pharmacological effects of pinesterol diglucoside and finds that its analgesic mechanism is mediated by inhibiting TTX-sensitive voltage-gated sodium ion channels in dorsal root ganglia, thereby providing use of pinesterol diglucoside in preparing drugs for treating chronic pain, and confirms for the first time through in vivo experiments that pinesterol diglucoside has the effects of treating neuropathic pain caused by partial sciatic nerve injury and chronic pain caused by ischemia-reperfusion after compression of ankle joints by rubber rings, and can be used for preparing drugs for treating chronic pain.

[0034] In some embodiments, the chronic pain is neuropathic pain or chronic post-ischemic pain.

[0035] In some specific embodiments, the neuropathic pain is chronic pain induced by unilateral partial sciatic nerve injury.

[0036] In a specific embodiment, the neuropathic pain is mechanical allodynia and pinprick hyperalgesia induced by unilateral partial sciatic nerve injury.

[0037] In some specific embodiments, the chronic post-ischemic pain is chronic pain induced by ischemia-reperfusion after unilateral ankle joint compression by a rubber ring.

[0038] In a specific embodiment, the chronic post-ischemic pain is mechanical allodynia induced by ischemia-reperfusion after unilateral ankle joint compression via a rubber ring.

[0039] In some specific embodiments, the dosage form of the drug is a pharmaceutically acceptable injection dosage form.

[0040] In some specific embodiments, the pinesterol diglucoside is the only active ingredient of the drug.

[0041] In some specific embodiments, the single application dose of the pinesterol diglucoside is 5 mg / kg.

[0042] In some specific embodiments, the drug achieves the purpose of treating the chronic pain by significantly inhibiting the function of tetrodotoxin-sensitive voltage-gated sodium ion channels on dorsal root ganglion neurons.

[0043] The following describes it in detail through specific embodiments.

[0044] The pinesterol diglucoside used in the examples (chemical formula: ) are commercially available.

[0045] Example 1

[0046] The invention discloses a method for preparing a drug for treating neuropathic pain, wherein the neuropathic pain is neuropathic pain caused by partial sciatic nerve damage, the single application dose of the drug is 5 mg / kg for rats, the dosage form of the drug is an injection dosage form, and the application route is intraperitoneal injection.

[0047] Example 2

[0048] The invention discloses a method for preparing a drug for treating chronic post-ischemic pain, wherein the chronic post-ischemic pain is chronic pain caused by ischemia-reperfusion after compression of a unilateral ankle joint by a rubber ring, the single application dose of the drug is 5 mg / kg for rats, the dosage form of the drug is an injection dosage form, and the application route is intraperitoneal injection.

[0049] The following animal and cell experiments further illustrate the effects and mechanisms of the above Examples 1-2:

[0050] 1. Experimental Materials

[0051] 1. Animal handling

[0052] Male Sprague Dawley rats, 150-250 g, were purchased from Guangdong Medical Experimental Animal Center, animal production license number: SCXK (Yue) 2018-0002. Feeding conditions included standard feed, tap water, room temperature maintained at (24 ± 2) °C, humidity 50-60%, and daily light and dark time of 12 h each. Before the experiment, the animals were placed in the experimental environment for 3 days to adapt.

[0053] 2. Experimental drugs and instruments

[0054] Pinesterol diglucoside (MCE), prepared in DMSO, used immediately. Pentobarbital sodium (Sigma-Aldrich), collagenase IA (Worthington), neutral proteinase (Worthington), poly-D-lysine (Sigma-Aldrich), fetal bovine serum (Gibco), DMEM (Gibco), penicillin / streptomycin double antibody (Gibco), TTX (Sigma-Aldrich), acetone (Sigma-Aldrich), isoflurane (Rayward), Von Frey needle prick pain test kit (DanmicGlobal), 22G epidural puncture needle (BD), HEKA EPC 10-USB patch clamp system (HEKA).

[0055] 3. Experimental Animal Grouping and Drug Administration

[0056] For Example 1, the experimental rats were randomly divided into a sham operation group, a partial sciatic nerve injury (SNI) group, and a SNI+pine ester alcohol diglucoside (5 mg / kg) group. Pain behavior detection was performed on the 14th day after the rat surgical modeling. After verifying that the neuropathic pain model was successfully constructed, the SNI+pine ester alcohol diglucoside group was given the experimental drug (dosage 5 mg / kg, intraperitoneal injection), and the sham operation group and the SNI group were given an equal amount of normal saline in the same way, and pain behavior detection was performed at 0.5h, 1h, 3h, 5h, 24h and 48h after administration to evaluate the analgesic effect of pine ester alcohol diglucoside.

[0057] For Example 2, the experimental rats were randomly divided into a sham operation group, a chronic post-ischemic pain (CPIP) group, and a CPIP+pine ester alcohol diglucoside (5 mg / kg) group. Pain behavior detection was performed on the 14th day after the rat surgical modeling. After verifying that the chronic post-ischemic pain model was successfully established, the CPIP+pine ester alcohol diglucoside group was given the experimental drug (dosage 5 mg / kg, intraperitoneal injection), and the sham operation group and the CPIP group were given an equal amount of normal saline in the same way, and pain behavior detection was performed 1h, 3h, 5h and 24h after administration to evaluate the analgesic effect of pine ester alcohol diglucoside.

[0058] 4. Establishment of partial sciatic nerve injury model in rats

[0059] Spared Nerve Injury (SNI) surgery is widely used to establish an animal model of neuropathic pain because of its simple operation and significant effect. By cutting off the tibial nerve and common peroneal nerve that branch from the sciatic nerve, rats will experience persistent touch pain, hot and cold hyperalgesia, and persistent pain. After the rats were anesthetized with 2.5% isoflurane, the skin of the left thigh root was prepared and disinfected, the skin was incised, the muscles were separated, and the three branches of the sciatic nerve were exposed. The tibial nerve and common peroneal nerve were ligated in turn with 5.0 silk thread, and they were shortened in turn with ophthalmic scissors. The skin was sutured after hemostasis. The sham operation group only underwent incision, nerve exposure, and skin suture. After surgery, pain behavior tests were performed according to experimental needs. Rats with abnormal conditions such as paralysis and infection after surgery were eliminated.

[0060] 5. Establishment of chronic post-ischemic pain model in rats

[0061] Chronic Post-Ischemia Pain (CPIP) is induced by exposing the hind paw of experimental animals to prolonged ischemia-reperfusion. Rats were anesthetized with sodium pentobarbital (40 mg / kg, intraperitoneal injection) and a 7 / 32-inch inner diameter rubber O-ring (O-rings West, Seattle, WA) was placed proximal to the ankle joint of the left hind limb of the rat. The O-ring tightly compressed the hind limb, similar to the pressure and ischemia generated when a blood pressure cuff is inflated to 350 mmHg, for 3 hours. The sodium pentobarbital anesthesia was terminated 30-60 minutes after reperfusion, and the rats recovered completely immediately after the O-ring was removed. Sham-operated rats received exactly the same anesthesia, and the O-ring was cut and placed so that it was loosely around the ankle without blocking blood flow to the hind paw.

[0062] 2. Experimental process

[0063] 1. Pain behavioral testing

[0064] 1) Mechanical allodynia test (Von Frey Test): The animals were placed in a separate transparent box with a hollow mesh at the bottom. After the animals adapted to the environment and became quiet, Von Frey ciliary mechanical stimulation needles of different strengths (0.4-15.0 g) were passed through the mesh to vertically stimulate the rat's surgical hind paw for 7 seconds. Lifting the paw, licking the paw, or making a sound was recorded as a positive. The strength of the stimulation needle was recorded when the positive result was detected, and stimulation needles of a larger and smaller strength were selected for stimulation again. After several repetitions, the experimental results were recorded, and the paw withdrawal threshold of the rat was calculated using the Dixon non-parametric formula.

[0065] like Figure 1 As shown in the figure, on the 14th day after SNI surgery (14dpi), rats developed significant mechanical allodynia, manifested by a significant decrease in the 50% paw withdrawal threshold compared with the baseline (BL). One hour after intraperitoneal injection of 5mg / kg PDG or an equal amount of saline, the mechanical allodynia of the PDG group was significantly improved compared with the control group, and lasted until 24h after administration.

[0066] like Figure 4 As shown in the figure, on the 14th day after CPIP surgery (14dpi), rats developed significant mechanical allodynia, manifested by a significant decrease in the 50% paw withdrawal threshold compared with the baseline (BL). 1 hour after intraperitoneal injection of 5mg / kg PDG or an equal amount of saline, the mechanical allodynia of the PDG group was significantly improved compared with the control group, and lasted until 5h after administration.

[0067] 2) Acetone Test: Place the animal in a separate transparent box with a hollow mesh screen at the bottom. After the animal has adapted to the environment and is quiet, slowly approach the skin of the animal's hind paw on the surgical side with a syringe containing acetone, inject acetone (200 μL) into the skin surface and ensure that the acetone diffuses evenly and quickly to the surrounding skin and evaporates. If the animal trembles in the hind paw, lifts the leg, and licks, it is considered a positive reaction. Repeat the stimulation 5 times, with an interval of more than 1 minute each time, and record the incidence of positive reactions.

[0068] like Figure 3 As shown in the figure, on the 14th day after SNI surgery (14dpi), rats developed significant cold allsensitivity, which was manifested by a significant increase in the acetone stimulation response rate compared with the baseline (BL). After intraperitoneal injection of 5mg / kg PDG or an equal amount of saline, the PDG group did not show significant improvement in cold allsensitivity compared with the control group.

[0069] like Figure 6 As shown in the figure, on the 14th day after CPIP surgery (14dpi), rats developed significant cold allsensitivity, which was manifested by a significant increase in the acetone stimulation response rate compared with the baseline (BL). After intraperitoneal injection of 5mg / kg PDG or an equal amount of normal saline, the PDG group did not show significant improvement in cold allsensitivity compared with the control group.

[0070] 3) Pin Test: Place the rat in a separate transparent box with a hollow mesh at the bottom. After the rat adapts to the quiet environment, use a 22G epidural puncture needle to slowly approach the skin of the hind paw on the surgical side and apply a gradually increasing pressure perpendicular to the skin until a retraction reaction occurs. A quick and brief leg retraction is considered a negative reaction, and a leg retraction combined with continuous trembling, leg lifting, and licking is considered a positive reaction. Repeat 10 stimulations, with an interval of more than 1 minute each time, and record the incidence of positive reactions.

[0071] like Figure 2 As shown in the figure, on the 14th day after SNI surgery (14dpi), rats developed significant hyperalgesia, manifested by a significant increase in the acupuncture reaction rate compared with the baseline (BL). 0.5h after intraperitoneal injection of 5mg / kg PDG or an equal amount of saline, the hyperalgesia in the PDG group was significantly improved compared with the control group, and lasted until 24h after administration.

[0072] like Figure 5 As shown in the figure, on the 14th day after CPIP surgery (14dpi), rats developed significant hyperalgesia, manifested by a significant increase in the acupuncture reaction rate compared with the baseline (BL). After intraperitoneal injection of 5mg / kg PDG or an equal amount of saline, the PDG group did not show significant improvement in hyperalgesia compared with the control group.

[0073] 2. DRG sampling and primary neuron culture

[0074] After the experimental rats were anesthetized with 2.5% isoflurane, they were decapitated, the back skin and muscles were removed, the spine was transected along the iliac spine level to expose the spinal canal, the vertebrae were separated along the plane of the spinal canal, the DRG neurons were exposed, and the DRG neurons were carefully separated and stored in 3mL DMEM solution (including 3.125mg / mL neutral proteinase and 5mg / mL collagenase I), placed in a 37℃ shaker for digestion for 45min, centrifuged (800rpm, 25℃, 3min), the supernatant was removed, and placed in culture medium (DMEM, including 1% penicillin and streptomycin, 30ng / mL nerve growth factor and 10% FBS), inoculated on 12mm coverslips (pre-covered with poly-lysine and laminin) for culture, and given drug treatment (PDG 20μM or an equal amount of DMSO solvent) at the same time. After overnight incubation, whole-cell voltage clamp recording was performed.

[0075] 3. Determination of voltage-gated sodium channel function

[0076] Small-diameter rat DRG neurons (less than 30 μm, Aδ and C fiber pain afferent neurons) were selected for whole-cell voltage clamp recording. Extracellular solution included (mM): 140 NaCl, 30 tetraethylammonium chloride, 10 D-glucose, 3 KCl, 1 CaCl2, 0.5 CdCl2, 1 MgCl2 and 10 HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid, 2-hydroxyethylpiperazine-2-ethylenesulfonic acid), pH = 7.3 (mOsm / L = 310-315); intracellular solution included (mM): 140 CsF, 10 NaCl, 1.1 Cs-EGTA and 15 HEPES, pH = 7.4 (mOsm / L = 290-310). Patchmaster software and patch clamp amplifier (EPC10; HEKA Elektronik, Lambrecht, Germany) were used for recording. Current density recording scheme: Activation: Clamp voltage -60mV, gradually increase the voltage from -70mV to +60mV (5mV increase each time, 150ms in total) to depolarize the cell, record the electrical activity of the cell during this process, and analyze the peak current density and activation curve; Inactivation: Clamp voltage -60mV, gradually increase the voltage from -120mV to +10mV (10mV increase each time, 1000ms in total), record the electrical activity of the cell during this process, and calculate the inactivation curve with the maximum current ratio. Patch clamp data were analyzed by Fitmaster software (HEKA), and the cell capacitance was completely compensated manually, the series resistance compensation reached 60%, and the data with series resistance compensation exceeding 5MΩ were eliminated.

[0077] According to the different characteristics of tetrodotoxin (TTX)-sensitive and insensitive NaV channels, the effects of PDG on TTX-sensitive and insensitive NaV channels will be studied by the following electrochemical and pharmacological methods: TTX-sensitive NaV currents are obtained by subtracting the current of -40 mV from the current of -120 mV in the inactivation scheme, and TTX-insensitive NaV currents are recorded by acutely administering 1 μM TTX before recording to block TTX-sensitive NaV channels. All experiments were performed at room temperature (27°C).

[0078] like Figure 7 As shown in Figure 2, 20 μM PDG significantly inhibited the function of NaV channels, as shown by the inhibition of the current-voltage (IV) curve ( Figure 7 A) and a significant decrease in the total NaV peak current density ( Figure 7 B), while the activation curve of PDG to NaV channel ( Figure 7 C in), inactivation curve ( Figure 7 The D) characteristics have no significant effect.

[0079] like Figure 8 As shown, in order to further clarify the selective inhibitory effect of PDG on TTX-sensitive and TTX-insensitive NaV channels, the two types of NaV channels were distinguished by electrochemical and pharmacological methods according to their different characteristics. The results showed that 20 μM PDG significantly inhibited the peak current density of TTX-sensitive NaV channels ( Figure 8 A), but had no significant inhibitory effect on TTX-insensitive NaV channels, as shown by the peak current density ( Figure 8 B in), IV curve ( Figure 8 C in), activation curve ( Figure 8 D) and inactivation curve ( Figure 8 There were no significant statistical differences among the groups in E).

[0080] The present invention confirms for the first time that pinesterol diglucoside has the effect of treating neuropathic pain caused by partial sciatic nerve injury and chronic pain caused by ischemia-reperfusion after compression of the ankle joint by a rubber ring, and can be used for preparing a therapeutic drug for chronic pain.

[0081] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. Use of pinesterol diglucoside in preparing a drug for treating chronic pain.

2. The use of pinesterol diglucoside according to claim 1, characterized in that: The chronic pain is neuropathic pain or chronic post-ischemic pain.

3. The use of pinesterol diglucoside according to claim 2, characterized in that: The neuropathic pain is chronic pain induced by unilateral partial sciatic nerve injury.

4. The use of pinesterol diglucoside according to claim 3, characterized in that: The neuropathic pain is mechanical allodynia and pinprick hyperalgesia induced by unilateral partial sciatic nerve injury.

5. The use of pinesterol diglucoside according to claim 2, characterized in that: The chronic post-ischemic pain is chronic pain induced by ischemia-reperfusion after compression of a unilateral ankle joint by a rubber ring.

6. The use of pinesterol diglucoside according to claim 5, characterized in that: The chronic post-ischemic pain is mechanical allodynia induced by ischemia-reperfusion after compression of the unilateral ankle joint by a rubber ring.

7. The use of pinesterol diglucoside according to claim 1, characterized in that: The dosage form of the drug is an injection dosage form permitted in pharmaceutical science.

8. The use of pinesterol diglucoside according to claim 1, characterized in that: The pinesterol diglucoside is the only active ingredient of the drug.

9. The use of pinesterol diglucoside according to claim 7 or 8, characterized in that: The single application dosage of the pinesterol diglucoside is 5 mg / kg.

10. The use of pinesterol diglucoside according to any one of claims 1 to 8, characterized in that: The drug treats the chronic pain by inhibiting the function of tetrodotoxin-sensitive voltage-gated sodium ion channels on dorsal root ganglion neurons.

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