Application of Corynebacterium casei in preparation of medicine for preventing and treating lung injury

Abstract

The present invention belongs to the field of biomedicine technology, and in particular to the application of Corynebacterium casei in the preparation of medicines for preventing and treating lung injury. The present invention constructs a mouse model of lung injury caused by radon inhalation and finds that after exposure to different radon levels, the mice lose weight, increase the lung coefficient, reduce the lung tidal volume, minute ventilation and maximum inspiratory flow, and their respiratory function is inhibited. The alveolar cavity of the mice is abnormally expanded, the lung septum is thickened and fractured, accompanied by more fibrin exudation, obvious inflammatory infiltration appears near the bronchus, congestion occurs in small blood vessels, and collagen deposition in lung tissue can lead to the occurrence of pulmonary fibrosis, causing lung injury. Oral administration of Corynebacterium casei can effectively inhibit the above-mentioned phenomenon. Therefore, Corynebacterium casei can be used for the prevention and treatment of lung injury, especially lung injury caused by radon exposure.

Description

Technical Field

[0001] The invention belongs to the technical field of biomedicine, and particularly relates to the application of Corynebacterium casei in the preparation of medicines for preventing and treating lung injury. Background Art

[0002] Indoor radon is considered a major source of radiation exposure to humans. The inhaled dose from radon and its progeny accounts for approximately 48% of the average annual human dose from natural background radiation. Due to their specific mode of action, bronchial epithelial basal cells, mucus cells, and lung epithelial cells are important targets. Long-term radon exposure can cause oxidative stress, DNA damage, and inflammation in lung and bronchial epithelial cells, leading to chronic lung diseases, including pulmonary fibrosis and lung cancer.

[0003] Probiotics can enhance the body's ability to fight pathogens and protect against them. In recent years, numerous studies have explored the role of intestinal flora and probiotics in the prevention and treatment of respiratory diseases such as viral pneumonia, bacterial pneumonia, bronchial asthma, and chronic obstructive pulmonary disease (COPD). Corynebacterium casei is a Gram-positive bacterium related to Lactobacillus and other bacteria. It is non-pathogenic and commonly found in dairy products and soil. Studies have shown that it contributes to the balance of the human intestinal flora, but research on lung injury is limited. Summary of the Invention

[0004] The purpose of the present invention is to provide a new application of Corynebacterium casei to effectively inhibit lung collagen deposition and fibrosis, prevent and treat lung damage, especially prevent and treat lung damage caused by radon exposure.

[0005] In order to achieve the above object, the present invention provides the use of Corynebacterium casei in preparing a product for preventing and treating lung injury.

[0006] Preferably, the lung injury includes lung respiratory function damage.

[0007] Preferably, the pulmonary respiratory function impairment includes one or more of decreased pulmonary tidal volume, decreased minute ventilation and decreased maximum inspiratory flow.

[0008] Preferably, the lung injury comprises pulmonary fibrosis.

[0009] Preferably, the lung injury comprises lung collagen deposition.

[0010] Preferably, the lung injury comprises an increased lung index.

[0011] Preferably, the lung injury includes lung injury caused by radon exposure.

[0012] Preferably, the relative cumulative exposure dose of radon in the radon exposure is 60-120 WLM.

[0013] The present invention also provides a medicine for preventing and treating lung injury, wherein the effective ingredient of the medicine includes Corynebacterium casei.

[0014] Preferably, the drug is 10 8 CFU Corynebacterium casei / dose is formulated as a single-use dosage form. Beneficial effects

[0015] The present invention finds that administration of Corynebacterium casei can inhibit weight loss and increase in lung coefficient in mice, improve respiratory function, restore the decrease in lung tidal volume, minute ventilation and maximum inspiratory flow caused by lung injury, inhibit lung collagen deposition and fibrosis, and prevent and treat lung injury, especially lung injury caused by radon exposure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below.

[0017] Figure 1 is the content of Corynebacterium casei in the feces of mice after inhalation of different doses of radon;

[0018] Figure 2 This is a graph showing the changes in weight gain in mice after inhalation of different doses of radon;

[0019] Figure 3 This is a graph showing the changes in lung coefficients in mice after inhalation of different doses of radon;

[0020] Figure 4 This is the result of tidal volume test on mice after inhalation of different doses of radon;

[0021] Figure 5 This is the result of minute ventilation test of mice after inhalation of different doses of radon;

[0022] Figure 6 This is the test result of the maximum inspiratory flow rate of mice after inhalation of different doses of radon;

[0023] Figure 7 The results of H&E staining of mouse lung tissue after inhalation of different doses of radon; the scale bar is 250μm;

[0024] Figure 8 The figure shows the H&E scoring results of mouse lung tissue after inhalation of different doses of radon;

[0025] Figure 9 The Masson staining results of mouse lung tissue after inhalation of different doses of radon; the scale bar is 250μm;

[0026] Figure 10This is the Masson quantitative analysis result of mouse lung tissue after inhalation of different doses of radon;

[0027] In the figure, ns means no statistical significance, **** means p <0.0001, *** indicates p <0.001, ** indicates p <0.01, * indicates p <0.05. DETAILED DESCRIPTION

[0028] The present invention provides the use of Corynebacterium casei in preparing a product for preventing and treating lung injury.

[0029] As an embodiment, the product of the present invention is a drug or a reagent; as an embodiment, the product of the present invention is a drug.

[0030] The present invention does not have strict requirements on the source of the described Corynebacterium casei, conventional purchase is final product.As an embodiment, the Corynebacterium casei of the present invention can be the Corynebacterium casei of strain numbering BNCC353906, purchased from Beina Biological.

[0031] As an embodiment, the lung injury of the present invention includes lung injury caused by radon exposure. As an embodiment, the radon exposure of the present invention has a relative cumulative exposure dose of 60 to 120 WLM. As another embodiment, the radon exposure of the present invention has a concentration of 100,000 Bq / m 3 , time is 377~755h.

[0032] The present invention constructs a mouse model of lung injury caused by radon inhalation and finds that after exposure to different radon levels, the mice lose weight, increase their lung coefficient, decrease their tidal volume, minute ventilation, and peak inspiratory flow, and experience respiratory suppression. The mice also experience abnormal alveolar expansion, thickening and rupture of the lung septa, increased fibrin exudation, significant parabronchial inflammatory infiltration, congestion in small blood vessels, and collagen deposition in lung tissue, which can lead to the development of pulmonary fibrosis and lung injury. Oral administration of Corynebacterium casei effectively inhibits these phenomena. Therefore, Corynebacterium casei can be used to prevent and treat lung injury caused by radon exposure.

[0033] The present invention also provides a medicine for preventing and treating lung injury, wherein the active ingredient of the medicine includes Corynebacterium casei. As an embodiment, the medicine of the present invention is 10 8 CFU Corynebacterium casei / dose is formulated as a single-use dosage form.

[0034] The present invention also provides a method for preventing and treating lung injury, comprising gavage of the drug described in the above technical solution. As an embodiment, the dosage of the drug of the present invention is 20 g per mouse per time, based on the body weight of the mouse.

[0035] To further illustrate the present invention, the application of Corynebacterium casei provided by the present invention in the preparation of a medicament for preventing and treating lung injury is described in detail below with reference to the accompanying drawings and examples, but they should not be construed as limiting the scope of protection of the present invention. Example

[0036] 1. Experimental Materials

[0037] (1) Experimental animals: 36 C57 mice purchased from Spefox Biotechnology.

[0038] (2) Experimental reagents: Corynebacterium casei, purchased from Beina Biotechnology, strain number: BNCC353906;

[0039] Solvent: 0.01 M PBS solution, pH 7.4;

[0040] H&E staining kit was purchased from Solebro;

[0041] Masson staining kit, purchased from Solebro;

[0042] 2. Model Construction

[0043] The experimental mice were randomly divided into a control group (NC+PBS), a radon exposure group (Rn+PBS) and a microbiome intervention group (Rn+C.casei), with 12 mice in each group. The mice in the control group were exposed to background radon concentration (8.20 Bq / m 3 The radon exposure group and the microbiome intervention group were exposed to the HD-3 multifunctional radon chamber, with a radon exposure concentration of 100,000 Bq / m 3 The exposure time was 377 and 755 h, respectively, and the relative cumulative exposure dose was 60 and 120 working level months (WLM). Among them, the mice in the microbiota intervention group were exposed to radon for 10 8 CFU / 20g, and gavage with Corynebacterium casei (dissolved in PBS solution before gavage) every day for one week to establish a microbiota intervention mouse model; before radon exposure, the mice in the control group and radon exposure group were gavaged with the same dose of PBS solution as that in the microbiota intervention group every day for one week to establish a solvent control intervention mouse model and a radon inhalation-induced lung injury mouse model.

[0044] 3. Experimental testing and conclusions

[0045] (1) After the mice in different treatment groups were exposed to radon by inhalation, the content of Corynebacterium casei in the feces of mice after exposure to different radon levels was detected by qPCR according to the existing technology (doi: 10.1186 / s40168-022-01227-w). The results are as follows: Figure 1 As shown. Figure 1 It can be seen that exposure to different radon levels can reduce the content of Corynebacterium casei in mouse feces, while oral administration of Corynebacterium casei can significantly increase the content of Corynebacterium casei in mouse feces after radon exposure and maintain a high abundance during the exposure period ( Figure 1 ).

[0046] (2) Pulmonary fibrosis may be accompanied by symptoms of decreased appetite and weight loss. The lung coefficient is determined by dividing the lung wet weight (mg) by the body weight (g), which can dynamically reflect the progression of lung disease. With the development of lung inflammation and fibrosis, lung exudation increases, water content increases, various proteins infiltrate the lung tissue, and the collagen content of the lung increases, resulting in an increase in lung weight and an increase in the lung coefficient. Therefore, the dynamic changes in weight gain and lung coefficient of mice in different treatment groups after radon inhalation poisoning were detected; among them, the weight gain was the weight after exposure (g) minus the weight before exposure (g), and the test results were as follows: Figure 2 and Figure 3 As shown. Figure 2 and Figure 3 It can be seen that exposure to different radon levels can cause weight loss in mice and increase the lung coefficient, indicating the occurrence of pulmonary fibrosis, while oral administration of Corynebacterium casei can effectively inhibit this phenomenon and prevent and treat lung damage.

[0047] (3) The specific manifestations of pulmonary fibrosis are: 1. Decreased tidal volume (TV) and increased respiratory rate; 2. Decreased maximum inspiratory flow (PIF) and maximum expiratory flow; 3. Decreased mid-expiratory flow rate and minute ventilation (MV), etc. Therefore, the tidal volume (TV, mL), minute ventilation (MV, mL), maximum inspiratory flow rate (PIF, mL / s) and other parameters of the mice in the same treatment group after radon inhalation were detected by non-invasive small animal respirometer to reflect the lung function level of the mice. The results are as follows: Figures 4-6 As shown. Figures 4-6 It can be seen that exposure to different radon levels can reduce the tidal volume, minute ventilation and maximum inspiratory flow of mice, suggesting that the lung function of mice is suppressed, which is common in restrictive lung diseases such as pulmonary fibrosis. Oral administration of Corynebacterium casei can significantly improve this phenomenon, improve the reduction in minute ventilation and maximum inspiratory flow of mice caused by radon exposure, improve lung function, and improve the lung function of mice after radon exposure.

[0048] (4) Three lung tissue sections were taken from each mouse in different treatment groups for H&E staining. Semi-quantitative lung pathology scoring was performed according to the method of Szapiel et al. (doi: 10.1164 / arrd.1979.120.4.89; doi: 10.1136 / jcp.41.4.467) to quantify the degree of lung injury. The scores of three sections of each mouse were averaged, and the average of 5 to 6 mice in each group was again taken to finally obtain the lung injury score of the mice in that group. The results are shown in the figure. Figure 7and Figure 8 As shown. Figure 7 and Figure 8 Radon exposure resulted in abnormal alveolar expansion, thickening and rupture of the lung septa, increased fibrin exudation, prominent parabronchial inflammatory infiltration, and congestion in small blood vessels. Lung damage worsened with cumulative exposure, but oral administration of Corynebacterium casei significantly improved these symptoms, significantly alleviating radon-induced lung damage.

[0049] (5) Three lung tissue sections were taken from each mouse in different treatment groups for Masson staining. The collagen content was quantitatively analyzed using Image J software. The average value of three sections for each mouse was taken, and the average value of 5 to 6 mice in each group was taken again. Finally, the quantitative analysis results of collagen in the lung tissue of the mice in this group were obtained. The results are shown in the figure. Figure 9 and Figure 10 As shown. Figure 9 and Figure 10 It can be seen that exposure to different radon levels promoted collagen deposition in the lung tissue of mice to varying degrees, while oral administration of Corynebacterium casei could significantly improve this phenomenon and ameliorate lung damage.

[0050] Based on the above content, it can be seen that Corynebacterium casei can prevent and treat lung damage, especially lung damage caused by radon exposure.

[0051] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. Corynebacterium casei ( Corynebacterium casei ) in the preparation of drugs for preventing and treating lung injury; The lung injury is caused by radon exposure; The Corynebacterium casei is the only active ingredient in the drug; The described Bacillus casei is Bacillus casei with strain number BNCC353906.

2. The use according to claim 1, characterized in that The lung injury includes lung respiratory function damage.

3. The use according to claim 2, characterized in that The pulmonary respiratory function impairment includes one or more of decreased pulmonary tidal volume, decreased minute ventilation, and decreased maximum inspiratory flow.

4. The use according to claim 1, characterized in that The lung injury includes pulmonary fibrosis.

5. The use according to claim 1, characterized in that The lung damage includes collagen deposition in the lungs.

6. The use according to claim 1, characterized in that The lung damage includes an increase in lung volume.

7. The use according to claim 1, characterized in that The relative cumulative exposure dose of radon in the radon exposure is 60-120 WLM.

8. The use according to claim 1, characterized in that The drug is 10 8 CFU Corynebacterium casei / dose is formulated as a single-use dosage form.

Images