A method for constructing a model of organ damage by hyperlipidemia

Abstract

The present application relates to a kind of methods for constructing the model of organ damage of hyperlipidemia, belong to experimental animal model construction technical field, with SD male rats as experimental object, by long-term feeding of high-fat high-salt feed induction: S1, adaptive feeding: select 8 weeks old SD male rats, adaptive feeding 7 days, according to weight random block grouping;S2, high-fat feed induction: model group is given high-fat high-salt feed feeding, blank group is given ordinary feed feeding, continues to feed 8 weeks;The high-fat high-salt feed is 43.6% of ordinary feed, casein 12.2%, sucrose 15%, premix 2.1%, salt 6%, lard 18.6%, cholesterol 2%, bile salt 0.5% by mass percentage;S3, model verification: after feeding 8 weeks, detect fasting blood lipid four, model group compared with blank group blood lipid index has significant difference, then indicate that hyperlipidemia-induced kidney injury model construction is successful.The present application is moderate in modeling cycle, phenotype is stable, and the hyperlipidemia-induced kidney injury of evaluation index is comprehensive.

Description

Technical Field

[0001] This invention relates to the field of experimental animal model construction technology, and in particular to a method for constructing a model of organ damage caused by hyperlipidemia. Background Technology

[0002] Hyperlipidemia is a chronic metabolic disease characterized by abnormally elevated levels of one or more lipid components in the blood plasma. In addition to the cardiovascular system, recent studies have increasingly demonstrated that hyperlipidemia-induced renal injury (HLD-RI) plays a crucial role in its development and progression. The kidneys, as highly perfused metabolic organs, are highly sensitive to lipid metabolism abnormalities. In a hyperlipidemic state, abnormally elevated circulating lipids and lipoproteins can act on kidney tissue through multiple pathways, inducing a series of structural and functional changes. Studies have found significant lipid deposition in the glomerular mesangial area and renal tubular epithelial cells in high-fat diets or hereditary dyslipidemia models. This abnormal lipid accumulation not only directly interferes with cellular energy metabolism but also triggers lipotoxic reactions, leading to glomerular sclerosis, tubulointerstitial damage, and accelerated fibrosis.

[0003] Existing models of hyperlipidemia-induced kidney injury have the following limitations: Simple high-fat diet-induced models have a long modeling period, typically requiring 12-24 weeks to develop significant kidney damage, and their stability is poor; gene knockout models (such as ApoE⁻ / ⁻, LDLR⁻ / ⁻), while accelerating the atherosclerosis process, have high animal breeding costs, require strict feeding conditions, and differ from the pathogenesis of primary hyperlipidemia in humans; some models only focus on changes in blood lipid indicators, lacking a systematic evaluation of renal function, hemorheology, and renal pathological structure, making it difficult to comprehensively reflect the pathological process of hyperlipidemia-induced kidney injury. Therefore, developing a rat model of hyperlipidemia-induced kidney injury with a moderate modeling period, stable phenotype, and comprehensive evaluation indicators is a pressing technical problem to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the background art by proposing a method for constructing a model of hyperlipidemia-induced kidney injury that has a moderate modeling cycle, stable phenotype, and comprehensive evaluation indicators.

[0005] The technical solution of this invention: A method for constructing a model of organ damage caused by hyperlipidemia, using male SD rats as experimental subjects, and inducing damage through long-term feeding with a high-fat, high-salt diet, specifically including the following steps: S1 Adaptive Feeding: Eight-week-old male SD rats were selected and acclimatized for 7 days, and then randomly divided into groups according to their body weight. S2 High-Fat Feed Induction: The model group was fed a high-fat, high-salt diet, while the control group was fed a normal diet, for a total of 8 weeks. The high-fat, high-salt diet, by weight percentage, consisted of 43.6% normal diet, 12.2% casein, 15% sucrose, 2.1% premix, 6% salt, 18.6% lard, 2% cholesterol, and 0.5% bile salts. S3 model validation: After 8 weeks of feeding, four fasting blood lipid parameters were measured. The blood lipid parameters of the model group and the blank group showed significant differences (P<0.05), indicating that the hyperlipidemia-induced kidney injury model was successfully constructed.

[0006] Preferably, the rats are housed in a barrier system with an ambient temperature maintained at 22-26°C and a humidity of 45-65%, using a 12-hour light-dark cycle.

[0007] Preferably, the four lipid parameters validated by the model include total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C).

[0008] Preferably, after successful model construction, the following evaluation metrics are also included: (1) Renal function indicators: Serum urea (UREA), uric acid (UA), and creatinine (CREA) levels were measured; (2) Hemorheological parameters: detection of whole blood viscosity, plasma viscosity, and fibrinogen content; (3) Renal pathological examination: HE staining was used to observe the pathological changes in renal tissue, and the Remuzzi scoring method was used to score the pathological damage of the kidney.

[0009] Compared with the prior art, the present invention has the following beneficial technical effects: This invention employs a high-fat, high-salt diet to induce lipid metabolism disorders and early kidney damage in SD rats within 8 weeks. The modeling period is moderate, eliminating the need for gene knockout animals and effectively reducing experimental costs. Furthermore, the use of a clinically common high-fat, high-salt diet as the inducing factor objectively recreates the pathogenesis of hyperlipidemia in clinical practice, resulting in a high model transfer value. In addition, the randomized block design effectively controls weight differences between groups. Combined with multi-dimensional evaluation indicators such as lipid profiles, renal function, hemorheology, and renal pathology, the model comprehensively reflects the pathological process of hyperlipidemia-induced kidney damage, ensuring the systematic and reliable nature of the model evaluation. This provides a stable, economical, and clinically pathologically sound experimental tool for studying the mechanisms of hyperlipidemia-related kidney damage and screening drugs. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention. Detailed Implementation

[0012] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0013] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0014] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is mutually exclusive, either alone or selectively, with other embodiments.

[0015] Secondly, the present invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.

[0016] like Figure 1 As shown, this invention proposes a method for constructing a model of organ damage caused by hyperlipidemia. Using male SD rats as experimental subjects, the model is induced by long-term feeding with a high-fat, high-salt diet. The method specifically includes the following steps: S1 Adaptive Feeding: Eight-week-old male SD rats, weighing 200±20g, were selected and acclimatized for 7 days, then randomly divided into groups according to body weight. The rats were housed in a barrier system with an ambient temperature maintained at 22-26℃ and humidity at 45-65%, using a 12-hour light-dark cycle.

[0017] S2 High-Fat Feed Induction: The model group was fed a high-fat, high-salt diet, while the control group was fed a normal diet, for a total of 8 weeks. The high-fat, high-salt diet, by weight percentage, consisted of 43.6% normal diet, 12.2% casein, 15% sucrose, 2.1% premix, 6% salt, 18.6% lard, 2% cholesterol, and 0.5% bile salts, and was purchased from Wuxi Fanbo Biotechnology Co., Ltd.

[0018] S3 Model Validation: After 8 weeks of feeding, the patient was fasted for 10 hours but allowed free access to water. Blood was collected by tail amputation, centrifuged at 3000 rpm for 10 minutes, and the supernatant serum was collected. TC, TG, HDL-C, and LDL-C were measured using a lipid profiler with the assistance of a lipid assay kit. Significant differences in lipid parameters were observed between the model group and the control group (P<0.05), indicating that the hyperlipidemia-induced kidney injury model was successfully established.

[0019] Example 1 Construction of a rat model of kidney injury induced by hyperlipidemia Animal grouping Seventy male SD rats, 8 weeks old and weighing 200±20g, were selected. After 7 days of acclimatization feeding, they were randomly divided into two groups according to their body weight: a control group (n=10) and a model group (n=60).

[0020] High-fat diet induction modeling The control group was fed a normal diet, while the model group was fed a high-fat, high-salt diet for 8 weeks. The high-fat, high-salt diet consisted of 43.6% normal feed, 12.2% casein, 15% sucrose, 2.1% premix, 6% salt, 18.6% lard, 2% cholesterol, and 0.5% bile salts.

[0021] Model Validation (Weekend 8) Eight weeks after feeding, lipid profile, renal function, hemorheology, and renal pathology were performed.

[0022] Four lipid profiles: Serum TC, TG, and LDL-C levels were significantly elevated in the model group, while HDL-C levels were significantly decreased. The differences were statistically significant compared with the blank group (P<0.05), confirming the successful establishment of the lipid metabolism disorder model.

[0023] Renal function indicators: Serum levels of CREA, UREA, and UA were significantly elevated in the model group, and the differences were statistically significant compared with those in the blank group (P<0.05), confirming that hyperlipidemia had caused renal function damage.

[0024] Hemorheological parameters: The whole blood viscosity, plasma viscosity and fibrinogen content in the model group were significantly increased, and the differences were statistically significant compared with the blank group (P<0.05), confirming that hyperlipidemia leads to abnormal blood rheology.

[0025] Renal pathology: The model group showed significant pathological changes in renal tissue, including renal tubular dilation, formation of proteinoid casts within the lumen, swelling and degeneration of renal tubular epithelial cells, disordered glomerular structure, increased intraglomerular cells, and interstitial inflammatory cell infiltration. The Remuzzi scoring method was used to assess renal injury pathology; the model group scored significantly higher than the control group (P<0.05), confirming that hyperlipidemia induced renal tissue pathological damage.

[0026] Example 2: Modeling and Validation of a Fructose-Based Water Substitution Program (Long-Term Modeling Validation) The basic steps are the same as in Example 1, except that the modeling period is extended to 12 weeks to observe the progression of kidney damage caused by a long-term high-fat diet.

[0027] Validation results: At the end of week 12, the model group showed further aggravation of dyslipidemia, continued deterioration of renal function indicators, more obvious renal pathological damage, and increased degree of renal tubular dilation and interstitial fibrosis, confirming the time dependence and pathological progression characteristics of the model.

[0028] Comparative analysis To verify the unexpected technical effects produced by the synergistic effect of multiple factors in this invention, the following comparative examples were set up for verification: Comparative Example 1 (Standard Feed Group): Patients were fed a standard feed for 8 weeks without high-lipid intervention. Results showed no significant abnormalities in the four lipid profiles, normal renal function indicators, and no obvious pathological changes in the kidneys.

[0029] Comparative Example 2 (High-Fat Only Group): Patients were fed a high-fat only diet (without bile salts) for 8 weeks. Results showed only a slight increase in blood lipids, no significant abnormalities in renal function indicators, and mild renal pathological changes, with only mild renal tubular epithelial cell degeneration observed.

[0030] Comparative Example 3 (High-fat, high-sugar group): The patient was fed a high-fat, high-sugar diet (without bile salts and salt) for 8 weeks. The results showed that the increase in blood lipids was limited, the renal function was not significantly impaired, and the degree of hemorheological abnormalities was mild. It was not possible to fully simulate the pathological process of renal injury induced by clinical hyperlipidemia.

[0031] In summary, this invention successfully established a stable hyperlipidemia-induced kidney injury model in SD rats through a combination of high-fat and high-salt diets. This model comprehensively reflects multi-dimensional pathological features such as lipid metabolism disorders, kidney function impairment, hemorheological abnormalities, and renal pathological changes. The modeling period is moderate, the operation is simple, and the reproducibility is good, providing a reliable experimental platform for the study of the mechanism of hyperlipidemia-related kidney injury and drug screening.

[0032] The high-fat, high-salt diet method can stably induce lipid metabolism disorders and early kidney damage in SD rats within 8 weeks. The modeling period is moderate, and gene knockout animals are not required, effectively reducing experimental costs. Furthermore, this method uses a clinically common high-fat, high-salt diet as the inducing factor, objectively reproducing the pathogenesis of hyperlipidemia in clinical practice, resulting in high model transfer value. In addition, the randomized block design effectively controls the weight difference between groups. Combined with multi-dimensional evaluation indicators such as lipid profile, renal function, hemorheology, and renal pathology, the model comprehensively reflects the pathological process of hyperlipidemia-induced kidney injury, ensuring the systematicity and reliability of model evaluation. Therefore, it provides a stable, economical, and clinically pathologically consistent experimental tool for the study of the mechanism of hyperlipidemia-related kidney injury and drug screening.

[0033] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A method for constructing a model of organ damage caused by hyperlipidemia, characterized in that: Using male SD rats as experimental subjects, the rats were induced to develop susceptibility through long-term feeding with a high-fat, high-salt diet. The specific steps included: S1. Adaptive feeding: Eight-week-old male SD rats were selected and acclimatized for 7 days, and then randomly divided into groups according to their body weight. S2. High-fat diet induction: The model group was fed a high-fat, high-salt diet, while the control group was fed a normal diet, for a total of 8 weeks. The high-fat, high-salt diet, by weight percentage, consisted of 43.6% normal diet, 12.2% casein, 15% sucrose, 2.1% premix, 6% salt, 18.6% lard, 2% cholesterol, and 0.5% bile salts. S3. Model Validation: After 8 weeks of feeding, four fasting blood lipid parameters were measured. The blood lipid indicators of the model group and the blank group showed significant differences (P<0.05), indicating that the hyperlipidemia-induced kidney injury model was successfully constructed.

2. The method for constructing a model of organ damage caused by hyperlipidemia according to claim 1, characterized in that, The rats were housed in a barrier system with an ambient temperature maintained at 22-26°C and a humidity of 45-65%, using a 12-hour light-dark cycle.

3. The method for constructing a model of organ damage caused by hyperlipidemia according to claim 2, characterized in that, The model validated four lipid parameters, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C).

4. The method for constructing a model of organ damage caused by hyperlipidemia according to claim 3, characterized in that, After the model is successfully built, the following evaluation metrics will also be checked: (1) Renal function indicators: Serum urea (UREA), uric acid (UA), and creatinine (CREA) levels were measured; (2) Hemorheological parameters: detection of whole blood viscosity, plasma viscosity, and fibrinogen content; (3) Renal pathological examination: HE staining was used to observe the pathological changes in renal tissue, and the Remuzzi scoring method was used to score the pathological damage of the kidney.

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