Procyanidine B2G2 derived from purple sweet potato Ningzi No.4 and application of procyanidine B2G2
By inhibiting inflammation and ferroptosis pathways through the proanthocyanidin B2G2 of purple sweet potato Ningzi 4, the problem of effective treatment for ALI has been solved, achieving significant reduction in lung damage and improvement in survival rate, and providing a safe and multi-targeted new approach to ALI treatment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NANTONG UNIV
- Filing Date
- 2025-12-04
- Publication Date
- 2026-05-01
AI Technical Summary
There is a lack of effective treatments for acute lung injury (ALI), especially those caused by Klebsiella pneumoniae (KP) infection. Existing treatments, such as glucocorticoids, have significant side effects and are not highly targeted.
Using proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4, a pharmaceutically acceptable drug composition was prepared for the treatment of ALI by inhibiting the release and expression of inflammatory factors TNF-α, IL-6, and IL-1β, regulating the expression of GPX4, SLC7A11, and HO-1 proteins, inhibiting the ferroptosis pathway, reducing ROS and MDA levels and intracellular Fe2+ accumulation.
It significantly reduces lung tissue damage scores and bacterial load, inhibits inflammatory responses, improves survival rates, reduces lung pathological damage, and provides a safe and effective new mechanism for ALI treatment, with multi-target effects and no significant toxic side effects.
Smart Images
Figure CN121949264A_ABST
Abstract
Description
A proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4 and its application Technical Field
[0001] This invention belongs to the field of biomedical technology, specifically relating to a proanthocyanidin B2G2 derived from the purple sweet potato Ningzi 4 and its application. Background Technology
[0002] Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), are common critical illnesses in clinical practice, with a mortality rate as high as 30%-40%. ALI can be caused by direct lung injury factors (such as pneumonia and aspiration) or indirect factors (such as sepsis and trauma). Pathological features include damage to alveolar epithelial cells and capillary endothelial cells, inflammatory cell infiltration, pulmonary edema, and hyaline membrane formation. Current clinical treatment mainly relies on symptomatic measures such as mechanical ventilation, anti-inflammatory glucocorticoids, and nutritional support. However, specific targeted drugs are lacking, resulting in limited efficacy and a high risk of complications.
[0003] Recent studies have shown that ferroptosis plays a crucial role in the pathogenesis of ALI (Alternative Lipid Injury). Ferroptosis is an iron-dependent form of programmed cell death triggered by the accumulation of lipid peroxides and regulated by proteins such as GPX4 and SLC7A11. Under conditions of infection or oxidative stress, ferroptosis in alveolar epithelial cells is exacerbated, leading to disruption of the lung barrier function and an inflammatory cascade. Although targeting the ferroptosis pathway has become a novel strategy for the treatment of ALI, no mature drugs are currently available for clinical application.
[0004] Natural products, due to their multi-target and low-toxicity characteristics, have shown potential in the treatment of ALI (Alternative Lipid Infection). Proanthocyanidins are widely found in plants such as grapes, blueberries, and purple sweet potatoes, and possess anti-inflammatory, antioxidant, and anti-apoptotic activities. Among them, B2-type proanthocyanidins have attracted attention due to their structural stability and bioavailability advantages, but the role of its derivative B2G2 (B2-3,3'-di-O-gallate) in ALI and ferroptosis has not been systematically studied. The purple sweet potato variety Ningzi 4, as a specialty, has tubers rich in structurally unique proanthocyanidin components, providing a new resource for the development of ALI treatment drugs. Summary of the Invention
[0005] Technical Problem Solved: This application addresses the shortcomings of existing technologies by providing a proanthocyanidin B2G2 derived from the purple sweet potato Ningzi 4 and its application. This solves the technical problems existing in the prior art, such as the lack of effective treatments for acute lung injury (ALI), particularly ALI caused by Klebsiella pneumoniae (KP) infection. This application also addresses the problems of significant side effects and poor targeting of existing treatments (such as glucocorticoids). For the first time, it reveals the mechanism by which B2G2 alleviates acute lung injury by simultaneously inhibiting both excessive inflammatory responses and ferroptosis pathways, providing a new, safe, and effective candidate drug for the preparation of clinical treatments.
[0006] To achieve the above objectives, this application provides the following technical solution: a proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4, wherein the molecular structure of proanthocyanidin B2G2 is B2-3,3'-di-O-gallate, and the molecular formula is C 44 H 34 O 20 .
[0007] The application of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 in the preparation of drugs for treating acute lung injury (ALI). The proanthocyanidin B2G2 can significantly reduce lung tissue damage score, lung wet-to-dry ratio and lung bacterial load, and inhibit the expression and release of inflammatory factors TNF-α, IL-6 and IL-1β.
[0008] Furthermore, the acute lung injury was induced by Klebsiella pneumoniae (KP) infection.
[0009] Furthermore, the B2G2 exerts its therapeutic effect by inhibiting the release and expression of inflammatory factors TNF-α, IL-6, and IL-1β in lung tissue.
[0010] Furthermore, B2G2 inhibits the ferroptosis pathway in lung tissue, upregulates the expression of GPX4, SLC7A11, and HO-1 proteins, and reduces ROS, MDA levels, and intracellular Fe. 2+ accumulation.
[0011] A pharmaceutical composition for treating acute lung injury, comprising the above-mentioned proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 and a pharmaceutically acceptable carrier.
[0012] Furthermore, the administration concentration of the proanthocyanidin B2G2 is 20 or 40 mg / kg body weight / day.
[0013] Furthermore, the pharmaceutically acceptable carrier includes one or more of the following: filler, stabilizer, diluent, adjuvant, excipient, binder, wetting agent, disintegrant, absorption promoter, surfactant, adsorbent, and lubricant.
[0014] This application also discloses the application of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 in the preparation of drugs that inhibit ferroptosis, wherein proanthocyanidin B2G2 inhibits ferroptosis by regulating the Nrf2 / GPX4 signaling pathway.
[0015] Furthermore, the iron death is associated with acute lung injury, infectious diseases, or oxidative stress.
[0016] Explanation of the principle: Currently, treatment strategies for infectious acute lung injury mainly focus on inhibiting pathogens and controlling excessive inflammatory responses, but insufficient attention is paid to accompanying cellular damage patterns such as ferroptosis. Proanthocyanidin B2G2, derived from the tuberous root of the purple sweet potato Ningzi 4, is a proanthocyanidin B2-3,3'-di-O-gallate, or B2G2. This invention is the first to isolate and identify proanthocyanidin B2G2 from Ningzi 4 and demonstrates through in vitro and in vivo experiments that it can alleviate KP-induced acute lung injury through a dual pathway of inhibiting inflammatory responses and ferroptosis, providing a new candidate for drug treatment of ALI. On the one hand, B2G2 can directly inhibit the inflammation induced by KP infection. B2G2 exerts a cascade effect, reducing the levels of key inflammatory factors and alleviating inflammatory infiltration and damage in lung tissue. On the other hand, by targeting and regulating core ferroptosis pathways such as Nrf2 / HO-1 and GPX4, B2G2 effectively reverses KP-induced lipid peroxidation and intracellular iron overload, thereby protecting alveolar epithelial cells from ferroptosis and maintaining the integrity of the lung barrier function. This synergistic mechanism of anti-inflammatory and anti-ferroptosis action is the core principle of B2G2's efficient relief of acute lung injury. Therefore, this application discloses the application of proanthocyanidin B2G2 in the preparation of drugs that inhibit ferroptosis and relieve bacterial acute lung injury (ALI). This invention provides a novel multi-target mechanism of action and drug development ideas for the treatment of acute lung injury.
[0017] This application provides a proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4 and its application. Compared with the prior art, it has the following beneficial effects: 1. This invention is the first to discover and confirm the significant effect of proanthocyanidin B2G2 in treating KP-induced acute lung injury, which can effectively improve lung pathological damage, increase survival rate and reduce inflammation level; 2. This invention reveals a new mechanism of B2G2 in treating acute lung injury, namely, by inhibiting the ferroptosis pathway, regulating key proteins such as GPX4 and SLC7A11, reducing lipid peroxidation and iron accumulation, providing a new target and idea for ALI treatment; 3. The B2G2 of this invention has no significant adverse effects on liver and kidney function indicators (ALT, AST, BUN, UA, CR) at effective doses, and all indicators are within the normal range, indicating that it has excellent safety and great potential for clinical application; 4. This invention provides an important basis for the development of compounds derived from natural products into anti-ALI drugs, with advantages such as wide availability, novel mechanism of action and no toxic side effects. Figure Descriptions: Figure 1 shows the molecular formula of proanthocyanidin B2G2 described in this application; Figure 2 shows the effect of B2G2 on the gross morphology of the lungs of mice infected with KP; Figure 3 shows the survival rate of mice infected with this application; Figure 4 shows the H&E staining results of lung tissue, demonstrating the ameliorative effect of B2G2 on pathological damage; Figure 5 shows the lung injury scoring chart of this application; Figure 6 shows the 4-HNE staining results of lung tissue, demonstrating the inhibitory effect of B2G2 on oxidative stress; Figure 7 shows the wet and dry lung tissue of this application. Figure 8 shows the statistical results of bacterial load in mouse lungs and blood, with the left figure showing the bacterial load in mouse lungs and the right figure showing the bacterial load in mouse blood; Figure 9 shows the expression results of inflammatory factor mRNA in lung tissue, with the left figure showing the expression results of IL-6, the middle figure showing the expression results of TNF-α, and the right figure showing the expression results of IL-1β; Figure 10 shows the content of CAT in lung tissue; Figure 11 shows the content of Fe in lung tissue. 2+Figure 12 shows the content of GSH in the lung tissue of this application; Figure 13 shows the content of MDA in the lung tissue of this application; Figure 14 shows the content of MPO in the lung tissue of this application; Figure 15 shows the content of SOD in the lung tissue of this application; Figure 16 shows the liver and kidney indicators in mouse serum of this application, where ALT is the liver indicator alanine aminotransferase, AST is the liver indicator aspartate aminotransferase, UA is the kidney indicator uric acid, BUN is the kidney indicator blood urea nitrogen, and CR is the kidney indicator creatinine, which is intended to illustrate the biosafety of B2G2; Figure 17 shows the protein concentration in BALF of this application; Figure 18 shows the number of inflammatory cells in BALF of this application, where the left image is the white blood cell count (WBC), the middle image is the monocyte (MN) lymphocyte count, and the right image is the polymorphonuclear leukocyte (PMN) count; Figure 19 shows the ELISA of TNF-α, IL-6, and IL-1β inflammatory factors in BALF of this application. Quantitative graphs, where the left graph shows the ELISA quantification of IL-1β inflammatory factor, the middle graph shows the ELISA quantification of IL-6 inflammatory factor, and the right graph shows the ELISA quantification of TNF-α inflammatory factor; Figure 20 shows the CFU graph in BALF of this application; Figure 21 shows the ELISA quantification graphs of TNF-α, IL-6, and IL-1β inflammatory factors in blood of this application, where the left graph shows the ELISA quantification of IL-6 inflammatory factor, the middle graph shows the ELISA quantification of IL-1β inflammatory factor, and the right graph shows the ELISA quantification of TNF-α inflammatory factor; Figure 22 shows the effect of B2G2 on KP-induced cell viability in MH-S and MLE-12 cells of this application, where the left graph shows the effect of B2G2 on KP-induced cell viability in MH-S cells, and the right graph shows the effect of B2G2 on KP-induced cell viability in MLE-12 cells; Figure 23 shows the effect of various death inhibitors of this application on MH-S; Figure 24 shows the effect of different concentrations of Erastin of this application on MH-S Figure 25 shows the effect of B2G2 on cell viability; Figure 26 shows the effect of B2G2 on the survival rate of Erastin-treated cells; Figure 27 shows the intracellular Fe content of each group of cells in this application. 2+ Figure 27 shows the changes in mitochondrial morphology observed by transmission electron microscopy in this application; Figure 28 shows the changes in superoxide dismutase (SOD) activity in cells of each group in this application; Figure 29 shows the release rate of lactate dehydrogenase (LDH) in cells of each group in this application; Figure 30 shows the changes in catalase (CAT) activity in cells of each group in this application; Figure 31 shows the changes in glutathione (GSH) level in cells of each group in this application; Figure 32 shows the changes in malondialdehyde (MDA) level in cells of each group in this application; Figure 33 shows the changes in ROS level in cells of each group in this application; Figure 34 shows the expression of ferroptosis-related proteins detected by Western blot in this application. Detailed Implementation
[0019] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. Experimental methods not specifically described in the embodiments are generally performed under conventional conditions or conditions recommended by the manufacturer.
[0020] Example 1: A proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4, wherein the molecular structure of proanthocyanidin B2G2 is B2-3,3'-di-O-gallate, and the molecular formula is C 44 H 34 O 20 The application of proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4 in the preparation of a drug for treating acute lung injury (ALI), where acute lung injury is induced by Klebsiella pneumoniae KP infection, is described. B2G2 exerts its therapeutic effect by inhibiting the release and expression of inflammatory factors TNF-α, IL-6, and IL-1β in lung tissue. B2G2 also inhibits the ferroptosis pathway in lung tissue, upregulates the expression of GPX4, SLC7A11, and HO-1 proteins, and reduces ROS (reactive oxygen species), MDA (malondialdehyde), and intracellular Fe2+ levels. 2+ accumulation.
[0021] B2G2 significantly alleviates KP-induced acute lung injury: 1. Experimental methods: A mouse model of acute lung injury induced by KP intranasal infection was established; control group, KP model group, low-dose KP+B2G2 group (20 mg / kg), high-dose KP+B2G2 group (40 mg / kg), and KP+dexamethasone positive control group (DEX) were set up; after treatment, the survival rate of mice was observed, lung tissue was taken for H&E staining to score the injury, the wet-to-dry ratio of the lung was calculated, and the bacterial load in lung tissue and blood was detected.
[0022] 2. Experimental Results: Compared with the KP model group, the survival rate of mice in the B2G2 treatment group was significantly improved. B2G2 significantly improved lung pathological damage caused by KP infection, significantly reduced lung tissue damage score and lung wet-to-dry ratio, and effectively reduced bacterial load in lung tissue and blood. Furthermore, liver and kidney function safety assessments showed that B2G2 treatment had no significant toxic effects on serum ALT, AST, BUN, UA, and CR levels in mice, demonstrating its good safety profile.
[0023] Example 2: An anthocyanin B2G2 derived from the purple sweet potato Ningzi 4 inhibits the inflammatory response of KP infection: Experimental method: Bronchoalveolar lavage fluid (BALF) was collected from mice in each group, and the total protein concentration and total number of inflammatory cells were detected. The concentrations of inflammatory factors TNF-α, IL-6, and IL-1β were detected by ELISA. The levels of the above inflammatory factors in the blood were also detected.
[0024] Experimental results: B2G2 treatment significantly reduced the total protein concentration and total number of inflammatory cells in BALF, and significantly inhibited the expression levels of key inflammatory factors such as TNF-α, IL-6, and IL-1β in BALF and blood, indicating that B2G2 has a strong anti-inflammatory effect.
[0025] Example 3: An anthocyanin B2G2 derived from the purple sweet potato variety Ningzi 4 inhibits KP-induced ferroptosis: 1. Experimental methods: B2G2 was administered to KP-infected macrophage cell lines (such as MH-S) or lung epithelial cell lines (such as MLE-12). Cell viability was detected by the CCK-8 assay, and intracellular Fe was measured using a kit. 2+ The levels of GSH, MDA, SOD, CAT, and LDH were measured. Mitochondrial morphology was observed using transmission electron microscopy, and the expression of key ferroptosis proteins such as GPX4, SLC7A11, and HO-1 was detected by Western blot.
[0026] 2. Experimental Results: B2G2 significantly reversed the decrease in cell viability induced by KP or ferroptosis inducers (Erastin). As shown in the attached figure, B2G2 treatment effectively reduced the accumulation of intracellular Fe²⁺ and ROS, alleviated the characteristic ultrastructural changes of ferroptosis such as mitochondrial atrophy, increased the activity of antioxidant enzymes (SOD, CAT) and GSH levels, and reduced MDA content and LDH release rate. Western blot results further confirmed that B2G2 significantly upregulated the protein expression of GPX4, SLC7A11, and HO-1, thereby inhibiting the ferroptosis pathway.
[0027] The present invention has been described above by way of example. It should be noted that any simple modifications, alterations or other equivalent substitutions that can be made by those skilled in the art without creative effort without departing from the core of the present invention fall within the protection scope of the present invention.
Claims
1. A proanthocyanidin B2G2 derived from the purple sweet potato variety Ningzi 4, characterized in that, The molecular structure of the proanthocyanidin B2G2 is B2-3,3'-di-O-gallate, and the molecular formula is C. 44 H 34 O 20 .
2. The use of the proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 as described in claim 1 in the preparation of a drug for treating acute lung injury (ALI).
3. The application of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 according to claim 2 in the preparation of drugs for treating acute lung injury, characterized in that: The acute lung injury was induced by Klebsiella pneumoniae (KP) infection.
4. The application of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 according to claim 2 or 3 in the preparation of drugs for treating acute lung injury, characterized in that: The B2G2 exerts its therapeutic effect by inhibiting the release and expression of inflammatory factors TNF-α, IL-6, and IL-1β in lung tissue.
5. The application of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 according to claim 2 in the preparation of drugs for treating acute lung injury, characterized in that: B2G2 inhibits the ferroptosis pathway in lung tissue, upregulates the expression of GPX4, SLC7A11, and HO-1 proteins, and reduces ROS levels, MDA (malondialdehyde), and intracellular Fe levels. 2+ accumulation.
6. A pharmaceutical composition for treating acute lung injury, characterized in that: It contains proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 as described in claim 1, and a pharmaceutically acceptable carrier.
7. The pharmaceutical composition for treating acute lung injury according to claim 6, characterized in that: The administration concentration of proanthocyanidin B2G2 is 20 or 40 mg / kg body weight / day.
8. The pharmaceutical composition for treating type 2 diabetes according to claim 6, characterized in that: The pharmaceutically acceptable carriers include one or more of the following: fillers, stabilizers, diluents, adjuvants, excipients, binders, wetting agents, disintegrants, absorption promoters, surfactants, adsorbents, and lubricants.
9. The use of proanthocyanidin B2G2 derived from purple sweet potato Ningzi 4 as described in claim 1 in the preparation of a drug to inhibit ferroptosis, characterized in that: The proanthocyanidin B2G2 inhibits ferroptosis by regulating the Nrf2 / GPX4 signaling pathway.
10. The application according to claim 9, characterized in that: Ferric death is associated with acute lung injury, infectious diseases, or oxidative stress.