Technology for reducing lead absorption in body

Abstract

The invention provides a technology for reducing in-vivo lead absorption, and relates to the technical field of pollutant health effects, and the technology comprises the following steps: carrying out lead exposure treatment on mice by referring to the blood lead level of normal people under environment concentration; dividing the mice into three groups, and respectively feeding the mice with low, medium and high proportions of protein diets so as to evaluate the lead absorption amounts in the mice under the condition of different proportions of protein diets; according to the in-vivo lead absorption amount of the mouse under different proportions of protein diet conditions, a diet reference scheme for reducing lead of a human body is provided. Three groups of mice are fed with low-proportion protein diet, medium-proportion protein diet and high-proportion protein diet respectively to determine the in-vivo lead absorption amount under different-proportion protein diet conditions; a diet reference scheme for reducing lead in a human body is provided according to the lead absorption amount in the mouse body under different proportions of protein diet conditions, so that the absorption of the human body on the ingested lead can still be reduced under the environment lead exposure level.

Description

Technical Field

[0001] The invention relates to the technical field of health effects of pollutants, and in particular to a technology for reducing lead absorption in the body. Background Art

[0003] The World Health Organization has stated that there is no blood lead concentration that is considered safe, which means that proposing strategies to reduce lead absorption and bioavailability has important environmental health value. It is even more important to find foods or drugs with less toxic side effects to eliminate or avoid the toxicity of lead to the human body. Intestinal lead absorption is an important way for lead to enter the human body. The intestine not only plays an important role in food digestion and nutrient absorption, but also has a protective function against exogenous toxins. Many studies have shown that the intestinal absorption capacity of lead decreases with age. The movement of lead in the blood and the transport to soft and hard tissues require the help of soluble carriers such as binding proteins. Such lead binding proteins are also very likely to mediate the bioavailability and toxicity of lead. Therefore, starting from the interaction between intestinal lead and protein absorption, developing nutritional dietary strategies to reduce lead absorption in the body may be safer and more effective than traditional methods. At the same time, experiments using mice as model animals will provide a theoretical basis and technical reference for the formulation of dietary plans to reduce lead absorption in the human body. Summary of the invention

[0004] The present invention aims to provide a technology for reducing lead absorption in the body, in order to at least partially solve at least one of the above problems.

[0005] To solve the above problems, the present invention provides a technology for reducing lead absorption in the body, the technology comprising:

[0006] The lead exposure concentration of mice was treated according to the blood lead level of normal people under reference environmental concentration, and the mice with the same lead exposure were divided into three groups;

[0007] Three groups of mice were fed low, medium, and high protein diets to determine the amount of lead absorbed by mice under different protein diet conditions;

[0008] Based on the amount of lead absorbed by mice under different protein diet conditions, a dietary reference plan for reducing lead in humans is proposed, thereby reducing the body's absorption of ingested lead under environmental lead exposure levels.

[0009] According to a preferred embodiment of the present invention, feeding three groups of mice with low, medium and high protein ratio diets to subsequently determine the amount of lead absorbed by the mice under different protein ratio diet conditions comprises:

[0010] The feeds for the low-protein diet treatment group, the normal-protein diet treatment group, and the high-protein diet treatment group were obtained by adjusting the mass percentage of casein and L-cysteine ​​in the total feed;

[0011] Each group of feed was quantitatively provided to the mice in the corresponding group;

[0012] After each group of mice adapted to the above feed for a first predetermined period of time, the lead content in the intestinal tissue of the mice was tested.

[0013] According to a preferred embodiment of the present invention, the mass percentages of casein and L-cysteine ​​in the total feed in the low-protein diet treatment group, the normal-protein diet treatment group and the high-protein diet treatment group are 5%, 20% and 35% respectively.

[0014] According to a preferred embodiment of the present invention, after obtaining feeds for a low-protein diet treatment group, a normal-protein diet treatment group, and a high-protein diet treatment group by adjusting the mass percentage of casein and L-cysteine ​​in the total feed, the technology further comprises:

[0015] Make up the feed to equal mass with corn starch.

[0016] According to a preferred embodiment of the present invention, the detection of lead content in mouse tissues comprises:

[0017] Determine the lead exposure concentration of mice by oral gavage, and perform lead gavage exposure on mice in each group;

[0018] After the second predetermined exposure time, the mice in each group were killed, and the intestinal tissues and blood of the mice in each group were collected;

[0019] The intestinal tissue was freeze-dried, the blood was centrifuged to obtain blood cell sediment, the intestinal tissue and blood cells were digested, the lead content in the digestion solution was determined by ICP-MS, and the lead content in the intestinal tissue and blood cells was calculated.

[0020] According to a preferred embodiment of the present invention, the lead exposure concentration of mice is 36.9 μg / ml, and lead nitrate solution is used as the lead source.

[0021] According to a preferred embodiment of the present invention, the normal protein diet treatment group is the control group, and the feed of the normal protein diet treatment group is prepared by adding an appropriate amount of pure water to AIN-93G, kneading it into a thin stick shape, and then freeze-drying it.

[0022] In summary, the technology of reducing lead absorption in the body of the present invention feeds three groups of mice with the same lead exposure with low, medium and high protein diets to determine the amount of lead absorbed in the mice under different protein diets; according to the amount of lead absorbed in the mice under different protein diets, a dietary reference plan for reducing lead in the human body is proposed, thereby achieving the reduction of the absorption of ingested lead by the human body under environmental lead exposure levels. The present invention is based on the discovery that a low-proportion (5%) protein diet can significantly reduce the lead level in mice, and can be used for the design of diets for the public (especially children) under environmental lead exposure. Compared with the limitations of traditional metal chelators for acute lead exposure and possible side effects, the present invention can achieve safe and effective further reduction of human lead levels under environmental chronic lead exposure levels, providing guidance for protecting the health of Chinese residents. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic flow chart of a technology for reducing lead absorption in the body provided by an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram of the lead content in the intestinal tissue of mice fed diets with different protein ratios according to an embodiment of the present invention;

[0026] Figure 3 Schematic diagram of lead content in blood cells of mice fed diets with different protein ratios according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and Examples. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, technology, article or equipment including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, technology, article or equipment. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, technology, article or equipment including the elements.

[0029] The present invention provides a technology for reducing lead absorption in the body, such as Figure 1 As shown, the technology includes:

[0030] S1, lead exposure concentration of mice treated with blood lead levels of normal people under reference environmental concentrations;

[0031] For example, referring to the blood lead level of normal people under environmental concentration, 36.9 μg / ml lead nitrate was used as the lead source to simulate the dietary lead intake of mice by gavage exposure.

[0032] In this embodiment, mice can be divided into a low-protein diet treatment group, a normal-protein diet treatment group, and a high-protein diet treatment group, wherein the normal-protein diet treatment group serves as the control group.

[0033] S2. Mice that were exposed to the same lead were divided into groups, and the mice in each group were fed low, medium, or high protein diets to determine the amount of lead absorbed by the mice under different protein diet conditions;

[0034] Specifically, the AIN-93G feed can be added with an appropriate amount of pure water relative to the control group (normal protein diet group), the feed can be carefully kneaded into a thin stick shape, and then freeze-dried to obtain the obtained product.

[0035] The difference between the low-protein diet treatment group, the normal protein diet treatment group and the high-protein diet treatment group is mainly that the mass percentage of casein and L-cysteine ​​in the feed is different. Preferably, the difference between the low-protein diet treatment group, the normal protein diet treatment group and the high-protein diet treatment group is mainly that the mass percentage of casein and L-cysteine ​​in the feed is 5%, 20%, and 35%, respectively. Further, corn starch can be used to supplement the feed to the same mass. After preparation, the feed of all treatment groups is quantitatively provided to mice for a total of 12 days, and the mice are free to eat feed and pure water.

[0036] After the mice in each treatment group adapted to the above-mentioned diet for 7 days, they were exposed to lead by gavage. After evaluation, it was determined that the lead gavage exposure concentration of the mice was 36.9 μg / ml. After 5 days of exposure, the mice in each group were killed and the intestinal tissue and blood of the mice were collected. The intestinal tissue was freeze-dried, the blood was centrifuged to obtain blood cell sediment, the intestinal tissue and blood cells were digested, and the lead content in the digestion solution was determined by ICP-MS, and then the lead content in the tissue was calculated. Figure 2 , 3 shown.

[0037] From the figure, we can see that the lead content in the intestine of mice in the normal diet group was 695.60±129.59ng / kg. Compared with the normal diet group, the lead content in the intestine of mice in the low-protein diet group was 338.55±92.94ng / kg, which was 48.67% lower; while the lead content in the intestine of mice in the high-protein diet group was 1174.76±80.55ng / kg, which was about 1.7 times higher ( Figure 2 ); In addition, the lead content in the blood cells of mice also decreased as the protein ratio in the mice's diet decreased ( Figure 3 ). Therefore, it can be determined that a low-protein diet can reduce the absorption of lead in the intestine of mice.

[0038] S3. Determine the dietary plan based on the amount of lead absorbed by mice under different protein diet conditions, providing a reference for reducing the body's absorption of ingested lead within a safe range.

[0039] It is determined by step S2 that a low-protein diet can reduce the absorption of intestinal lead. Based on this, a diet that can effectively reduce the absorption of ingested lead by the human body within a safe range can be established according to the absorption and accumulation of lead in mice under different protein diets. Taking Guangzhou citizens as an example, according to the literature (Int. J. Environ. Res. Public Health. 2019, 16, 1417.), a survey on dietary lead exposure of citizens of different ages in Guangzhou from 2011 to 2017 found that the average dietary lead exposure of the total population in Guangzhou was 0.4033 μg / kg body weight / day, among which the average dietary lead exposure of people aged 3 to 6, 7 to 17, 18 to 59 and ≥ 60 was 0.7466, 0.4739, 0.3759 and 0.4031 μg / kg body weight / day, respectively. Based on this, we can make dietary recommendations for people of different ages. For example, on the premise of meeting nutritional needs, appropriately reduce the protein intake of young people and the elderly, and reduce the consumption of eggs, dairy products and meat, so as to reduce lead absorption and greatly reduce the intellectual damage caused by lead to young people; and for people aged 18 to 59, the protein intake limit can be relaxed.

[0040] The present invention uses AIN 93G powder with different protein ratios as feed, and 36.9μg / ml lead nitrate is gavaged to simulate dietary lead intake, and a mouse experiment is carried out. By setting a low-protein diet group, a normal diet group, and a high-protein diet group, the lead content in the intestinal tissue of mice after 5 days of exposure is measured. The results showed that the lead content in the intestine of mice in the normal diet group was 695.60±129.59ng / kg. Compared with the normal diet group, the lead content in the intestine of mice in the low-protein diet group was 338.55±92.94ng / kg, which was 48.67% lower; while the lead content in the intestine of mice in the high-protein diet group was 1174.76±80.55ng / kg, which was about 1.7 times higher. In addition, the lead content in mouse blood cells also decreased with the decrease in the protein ratio in the mouse diet. Therefore, it is confirmed that a low-protein diet can reduce the absorption of lead in the intestine of mice. The present invention is based on the discovery that a low-ratio (5%) protein diet can significantly reduce the lead level in mice, and can be used for the diet design of people (especially children) under environmental lead exposure. Compared with the limitations of traditional metal chelators in acute lead exposure and possible side effects, the present invention can further reduce the lead level in the human body under the level of chronic environmental lead exposure safely and effectively, providing guidance for protecting the health of Chinese residents.

[0041] It should be clear that the present invention is not limited to the specific structures and processes described above and shown in the figures. For the sake of simplicity, a detailed description of the known technology is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the technical process of the present invention is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present invention.

[0042] It should also be noted that the exemplary embodiments mentioned in the present invention describe some technologies or systems based on a series of steps or devices. However, the present invention is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiments, or in a different order from the embodiments, or several steps can be performed simultaneously.

[0043] The above is only a specific implementation of the present invention. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned technical embodiments, and will not be repeated here. It should be understood that the protection scope of the present invention is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be covered within the protection scope of the present invention.

Claims

1. A technology for reducing lead absorption in the body, characterized in that: The techniques include: The lead exposure concentration of mice was treated with blood lead levels of normal people under reference environmental concentrations; The mice that had been exposed to the same lead were divided into three groups, and the three groups of mice were fed low, medium, and high protein diets in order to subsequently determine the amount of lead absorbed by the mice under different protein diet conditions; Based on the amount of lead absorbed by mice under different protein diet conditions, a dietary reference plan for reducing lead in humans is proposed, thereby reducing the body's absorption of ingested lead under environmental lead exposure levels.

2. The technology according to claim 1, characterized in that The method of feeding three groups of mice with low, medium and high protein ratio diets to subsequently determine the amount of lead absorbed by the mice under different protein ratio diet conditions includes: The feeds for the low-protein diet treatment group, the normal-protein diet treatment group, and the high-protein diet treatment group were obtained by adjusting the mass percentage of casein and L-cysteine ​​in the total feed; Each group of feed was quantitatively provided to the mice in the corresponding group; After each group of mice adapted to the above feed for a first predetermined period, the lead content in the mouse tissues was tested.

3. The technology according to claim 2, characterized in that The mass percentages of casein and L-cysteine ​​in the total feed in the low-protein diet treatment group, the normal-protein diet treatment group and the high-protein diet treatment group are 5%, 20% and 35% respectively.

4. The technology according to claim 2, characterized in that After obtaining feeds for a low-protein diet treatment group, a normal-protein diet treatment group, and a high-protein diet treatment group by adjusting the mass percentage of casein and L-cysteine ​​in the total feed, the technology further comprises: Make up the feed to equal mass with corn starch.

5. The technology according to claim 2, characterized in that The detection of lead content in mouse tissues comprises: Determine the lead exposure concentration of mice by oral gavage, and perform lead gavage exposure on mice in each group; After the second predetermined exposure time, the mice in each group were killed, and the intestinal tissues and blood of the mice in each group were collected; The intestinal tissue was freeze-dried, the blood was centrifuged to obtain blood cell sediment, the intestinal tissue and blood cells were digested, the lead content in the digestion solution was determined by ICP-MS, and the lead content in the intestinal tissue and blood cells of the mice was calculated.

6. The technology according to claim 1, characterized in that The lead exposure concentration for mice was 36.9 μg / ml, using lead nitrate solution as the lead source.

7. The technology according to claim 1, characterized in that The normal protein diet treatment group served as the control group. The feed of the normal protein diet treatment group was prepared by adding an appropriate amount of pure water to AIN-93G, kneading it into a thin stick shape, and then freeze-drying it.

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