Method for establishing animal model for long-term obesity of offspring caused by excessive feeding

Abstract

The invention discloses a method for establishing an animal model for long-term obesity of offspring caused by excessive feeding, and belongs to the technical field of biomedicine. The method specifically comprises the following steps: 1) selecting a suckling SD female mouse with a good health condition and 2-4 newly born SD suckling mice with normal vital signs to form an excessive feeding group; the method comprises the following steps: selecting a lactating SD female mouse with good health condition and 10-14 newly born SD suckling mice with normal vital signs to form a normal feeding group, and feeding in the same cage; (2) in the same-cage feeding process, except for supplying sufficient feed and water to the SD female rats, intervention of other people is not carried out; and 3) drawing weight growth curves of the two groups of SD suckling rats, and if the weight growth curve of the overfeeding group is obviously higher than that of the normal feeding group and the death rate of the SD suckling rats of the normal feeding group is lower than 0.1%, successfully establishing the animal model of long-term obesity of the offspring caused by overfeeding. The model provides feasible animal model support for research on exploration of influence of early life environment factors on obesity of individuals in different life development stages.

Description

Technical Field

[0001] The invention belongs to the field of biomedical technology, and in particular relates to a method for establishing an animal model of long-term obesity of offspring caused by overfeeding. Background Art

[0003] The family upbringing environment is an important environmental factor that affects childhood obesity. According to the theory of early childhood development, early life is a critical period for the establishment of eating behavior. However, the mechanism of the effect of infant feeding patterns on obesity is still unclear, and there is no unified and standardized exploration model. Therefore, by intervening in the feeding methods of suckling mice in early life, an animal model that simulates the early feeding methods of human infants can be constructed in a small mammal population, and then by strictly controlling the confounding factors in the growth and development process, the influence of early environmental factors on the occurrence and development of obesity in individuals at different life stages, such as childhood, adolescence and adulthood, can be explored. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies in the prior art and provide a method for establishing an animal model of long-term obesity in offspring caused by overfeeding.

[0005] The specific technical solutions adopted by the present invention are as follows:

[0006] The present invention provides a method for establishing an animal model of long-term obesity in offspring caused by overfeeding, and the specific steps are as follows:

[0007] S1: Select several lactating SD rats in good health and newly born SD rats with normal vital signs and place them in a rat breeding box, where the ratio of SD rats to SD rats is 1:(2-4), forming an overfeeding group, and keep them in the same cage;

[0008] S2: Select several lactating SD rats in good health and newly born SD rats with normal vital signs and place them in a rat breeding box, where the ratio of SD rats to SD rats is 1:(10-14), forming a normal feeding group, and raise them in the same cage;

[0009] S3: During the co-cage feeding, except for providing the SD mother mice with sufficient feed and water, no other human intervention was performed to ensure the normal life rhythm and circadian rhythm of the SD mother mice and SD baby mice;

[0010] S4: The overfeeding group and the normal feeding group were continued until the weaning period of the SD pups, and the weight growth curves of the SD pups in the overfeeding group and the normal feeding group were drawn. If the weight of the overfeeding group exceeded 20% of the average weight of the normal feeding group, and the weight growth curve of the overfeeding group was significantly higher than that of the normal feeding group, and the mortality rate of the SD pups in the overfeeding group was lower than 0.1% during the process, then the animal model of long-term obesity in offspring caused by overfeeding was successfully established.

[0011] Preferably, the overfeeding group comprises one lactating SD mother mouse and 2 to 4 SD suckling mice, which are housed in the same cage.

[0012] Preferably, the normal feeding group comprises one lactating SD mother mouse and 10 to 14 SD suckling mice, which are housed in the same cage.

[0013] Preferably, the size of the rat breeding box is 42×27×20 cm.

[0014] Preferably, the breastfeeding duration of the overfeeding group and the normal feeding group is 28 days.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The present invention innovatively proposes a method for overfeeding newborn SD rats. After starting overfeeding, the weight and mortality of the experimental animals are tracked and recorded every day, and their general physiological activity status, such as appearance, hair and mental state, is observed and recorded; then, by drawing a weight growth curve, the weight change trend of the SD rats in the overfeeding group and the normal feeding group is compared. It is found that the weight of the overfeeding group exceeds the average weight of the normal feeding group by 20%, and its weight growth curve is significantly higher than that of the normal feeding group (p<0.05), and the mortality rate of the SD rats in the overfeeding group is less than 0.1%.

[0017] (2) The present invention uses the above-mentioned overfeeding to construct an obese rat model for offspring. The results show that the obesity rate of the overfed rats in adulthood is higher than that in the normal feeding group. This provides a feasible animal model to support the influence of environmental factors in early life on obesity. It has theoretical significance and application value for in-depth research on the influence of family rearing environment in early life on the occurrence of obesity at different stages. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the weight curve of SD rats at different growth and development stages under the intervention of different feeding methods;

[0019] Figure 2 The body length curves of SD rats at different growth and development stages under different feeding interventions;

[0020] Figure 3The BMI box plots of SD rats in the overfed group and the normal fed group during the weaning period (28 days old);

[0021] Figure 4 Figure 2 is a box plot of BMI of SD rats in the overfed group and the normal fed group during adulthood (126 days of age). DETAILED DESCRIPTION

[0022] The present invention is further described and illustrated below in conjunction with the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly without conflicting with each other.

[0023] Example

[0024] This embodiment provides a method for establishing an animal model of long-term obesity in offspring caused by overfeeding, and the specific steps are as follows:

[0025] (1) Several lactating SD female mice in good physical condition were randomly selected and divided into an overfeeding group and a normal feeding group. One lactating SD female mouse was allocated to each cage of the overfeeding group and the normal feeding group, respectively.

[0026] (2) Several newborn SD mice were randomly selected and divided into an overfed group and a normal-fed group. The overfed group was allocated 4 SD mice with normal vital signs and good body shape per cage, while the normal-fed group was allocated 12 SD mice with normal vital signs and good body shape per cage.

[0027] (3) Lactating SD mothers and SD pups in the overfed group and the normal fed group were housed together. During the feeding period, no human intervention was performed except for providing the mothers with adequate feed and water.

[0028] (4) The feeding time of the overfeeding group and the normal feeding group continued until the SD pups were 28 days old when they were weaned. During this period, the weight of the pups was measured and the weight and length growth curves of the overfeeding group and the normal feeding group were drawn.

[0029] In this example, the weight growth curve of the overfeeding group within 28 days was significantly higher than that of the normal feeding group, and the mortality rate of SD suckling mice in the mouse feeding group was 0 (the mortality rate of the normal feeding group was 0.25%), then it was determined that the offspring obesity rat model was successfully established. This shows that the small nest feeding model provided by the present invention is effective in constructing an offspring obesity model.

[0030] In order to verify the weight changes of the overfed and normally fed suckling mice in adulthood, the mice in the artificial feeding group and the normally fed group were housed in separate cages 28 days after age. The feeding methods were as follows: After 28 days of age, the mice were randomly divided into groups and fed together in cages with four mice per cage. Sufficient ordinary feed and autoclaved water were supplied daily to ensure their free diet and normal circadian rhythm.

[0031] Figure 1 The weight curves of SD rats in the overfeeding group and the normal feeding group at different growth and development stages. Figure 1 It can be seen that the weight of the suckling mice in the overfed group was significantly higher than that in the normally fed group starting from infancy (11 days old), which indicates that the weight gain of the mice in the overfed group was higher than that in the normally fed group from infancy to adulthood, especially in adolescence (35 days old), the weight gain was much higher than that in the normally fed group, indicating that adolescence is a sensitive period for weight gain in obese mice and can be used as an intervention window period.

[0032] Figure 2 The body length curves of SD rats in the overfeeding group and the normal feeding group at different growth and development stages. Figure 2 It can be seen that the body length of the overfed mice group was significantly different from that of the normally fed mice group after weaning (i.e., 28 days of age). This shows that the overfed mice group was superior to the normally fed mice group in terms of body length growth from the late infancy to adulthood, and there was a significant difference after weaning, indicating that their body length development was longer than that of the normally fed mice group.

[0033] Figure 3 and Figure 4 The BMI box plots of SD rats in the overfed group and the normal feeding group during weaning (28 days old) and adulthood (126 days old) are shown. Figure 3 It can be seen that the BMI value of the overfed group of suckling mice at 28 days of age was significantly higher than that of the normal feeding group, which can indicate that the BMI of the overfed group of mice in infancy is significantly higher than that of the normal feeding group; Figure 4 It can be seen that the BMI value of the overfed group was significantly higher than that of the normally fed group at 126 days of age, which indicates that the BMI of the overfed group mice in adulthood was significantly higher than that of the normally fed group mice.

[0034] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A method for establishing an animal model of long-term obesity in offspring caused by overfeeding, characterized in that: The specific steps are as follows: S1: Select several lactating SD rats in good health and newly born SD rats with normal vital signs and place them in a rat breeding box, where the ratio of SD rats to SD rats is 1:(2-4), forming an overfeeding group, and keep them in the same cage; S2: Select several lactating SD mothers in good health and newly born SD pups with normal vital signs and place them in a rat breeding box, where the ratio of SD mothers to SD pups is 1:(10-14), forming a normal feeding group, and raise them in the same cage; S3: During the co-cage feeding, except for providing the SD mother mice with sufficient feed and water, no other human intervention was performed to ensure the normal life rhythm and circadian rhythm of the SD mother mice and SD baby mice; S4: Breast feeding was continued until the weaning period of SD pups in both the overfeeding group and the normal feeding group, and the weight growth curves of the SD pups in the overfeeding group and the normal feeding group were drawn. If the weight of the overfeeding group exceeded 20% of the average weight of the normal feeding group, and the weight growth curve of the overfeeding group was significantly higher than that of the normal feeding group, and the mortality rate of the SD pups in the overfeeding group was lower than 0.1% during the process, then the animal model of long-term obesity in offspring caused by overfeeding was successfully established.

2. The method for establishing an animal model of long-term obesity in offspring caused by overfeeding according to claim 1, characterized in that: In the overfeeding group, one lactating SD mother mouse and 2 to 4 SD puppies were housed in the same cage.

3. The method for establishing an animal model of long-term obesity in offspring caused by overfeeding according to claim 1, characterized in that: In the normal feeding group, one lactating SD mother mouse and 10 to 14 SD puppies were housed in the same cage.

4. The method for establishing an animal model of long-term obesity in offspring caused by overfeeding according to claim 1, characterized in that: The size of the rat breeding box is 42×27×20 cm.

5. The method for establishing an animal model of long-term obesity in offspring caused by overfeeding according to claim 1, characterized in that: The duration of breastfeeding in both the overfeeding group and the normal feeding group was 28 days.

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