The present invention relates to the field of genetic engineering, and relates to an application of a UTX gene in preparation of drugs for preventing or treating lipid diseases.
Histone methylation plays an important role in regulating metabolic diseases such as hyperlipidemia, obesity and non-alcoholic fatty liver disease (NAFLD).UTX (ubiquitously transcribed tetratricopeptide repeat on chromosome X) gene located on the X chromosome, is highly expressed in the liver, spleen, and brain tissues. As a histone demethylase that removes the di- and tri-methyl groups from histone H3K27 and activates gene expression, plays important roles in numerous biological and pathological processes. Previous study reported that UTX was upregulated in the renal mesangial and tubular cells of diabetic kidney disease and diabetic mice. In addition, the expression of hepatic gluconeogenesis gene PEPCK was significantly reduced when UTX knocked down in HepG2, indicating that UTX was involved in glucose metabolism in the body. Importantly, mice lacking UTX in adipocytes showed significantly decreased triacylglycerol synthesis activity, further revealing that UTX gene was closely related to lipid metabolism. However, the function of UTX in hyperlipidemia has not been reported.
Hyperlipidemia refers to high lipid level, which is caused by abnormal metabolism or transportation of cholesterol and triglyceride in blood. Studies have shown that the hyperlipidemia, as a high-risk factor for coronary heart disease, stroke, fatty liver, hyperuricemia and other diseases, is increased sharply and has a trend of younger age. “China's Cardiovascular Disease Report in 2010” showed that 18.6% of the population over 18 years old had dyslipidemia, and the number of patients had reached 200 million. According to statistics, 30 million people around the world die of related diseases caused by hyperlipidemia every year. It is known that the hyperlipidemia is the result of lipid metabolism disorder under the interaction of many factors such as heredity, environment and living behavior, and the pathogenesis is complex. Therefore, it is very important to carry out etiological research of hyperlipidemia, which will provide an important theoretical basis for clarifying the pathogenesis of hyperlipidemia. However, there are no reports on the function of the UTX in the hyperlipidemia.
In the previous research work, after adopting a genetic engineering technology to specifically knock out a UTX gene from a mouse liver tissue, the inventor found that the liver-specific UTX knockout mouse showed obvious hypercholesterolemia and hypertriglyceridemia, which suggested that it might be related to the occurrence and development of hyperlipidemia.
Object of the invention: the technical problem to be solved by the present invention is to provide an application of a UTX gene in preparation of drugs for preventing or treating lipid diseases.
The technical problem to be solved by the present invention is to provide an application of a UTX gene in preparation of lipid-lowering drugs.
The technical problem to be further solved by the present invention is to provide a method for knocking out a UTX gene from a mouse liver.
The technical problem to be further solved by the present invention is to provide an adenovirus vector, a UTX adenovirus as well as a preparation method and an application thereof.
The technical problem to be further solved by the present invention is to provide a therapeutic application of UTX overexpression on model with hyperlipidemia and NAFLD.
Besides, we also constructed a UTX overexpression adenovirus vector and transduced it into mice through tail-vein injection to specifically overexpress UTX gene in liver. H&E staining and hepatic triglyceride detection result ensure the therapeutic action of UTX gene for hyperlipidemia and NAFLD. Further, we should put more efforts on establishing an application of a UTX gene in preparation of drugs for preventing or treating lipid diseases.
Technical solution: in order to solve the technical problems above, the technical solution of the present invention is as follows: the present invention comprises an application of a UTX gene in preparation of drugs for preventing or treating lipid diseases.
The present invention further comprises an application of a UTX gene in preparation of lipid-lowering drugs.
The present invention further comprises a method for knocking out a UTX gene from a mouse liver which specifically knocks out a UTX gene from a liver tissue by constructing a genetically engineered mouse, comprising the following steps of:
The present invention further comprises an adenovirus vector, which comprises a UTX gene, and the vector can effectively overexpress the UTX gene in a liver cell.
The adenovirus vector is a pAdEasy-1 vector.
The present invention further comprises a UTX overexpression adenovirus, which comprises the adenovirus vector.
The present invention further comprises a preparation method of a UTX overexpression adenovirus, which comprises the following steps of:
A sequence of a forward primer amplified by PCR in the step 2) is shown in SEQ ID NO:1, and a reverse primer is shown in SEQ ID NO:2.
The cultured AD-293 cells in the step 4) are the AD-293 cells evenly inoculated in a culture dish at a density of 7 to 8*105/ml in a 5% CO2 incubator under 37° C. until a cell fusion degree reaches 70% to 80%.
The present invention further comprises applications of the adenovirus vector and the UTX overexpression adenovirus in preparation of drugs for preventing or treating lipid diseases.
The present invention further illustrates a method for overexpressing UTX gene specifically in a mouse liver, comprising the following steps of:
Beneficial effects: compared with the prior art, the present invention has the advantages as follows.
(I) Main Reagents
A UTX antibody used in the research is purchased from Genetex Company in America; a GAPDH antibody is purchased from Nanjing Bioworld Company; a Trizol reagent, a mRNA reverse transcription kit and a quantitative PCR kit are purchased from Invitrogen Company in America; a protein lysate, a protease inhibitor and protease K are purchased from Pierce Company in America; an ECL chemiluminescence detection kit is purchased from Nanjing Tiangen Biology Co., Ltd.; a PVDF membrane is purchased from Millipore Company in America; ordinary Taq enzyme is purchased from Nanjing Vazyme Company; DMEM medium, fetal bovine serum, pancreatin, PBS and streptomycin are purchased from Gibico Company in America; and glucose is purchased from Sigma Company in America.
(II) Main Instruments
UTL ultra-low temperature freezer: Thermo Company, U.S.
Gradient PCR instrument: Eppendorf Company, France
Gel imaging system: Bio-rad, U.S.
Electrophoresis apparatus, electrophoresis tank: Bio-rad, U.S.
Life ViiA7 fluorescent quantitative PCR instrument: Life Company, U.S.
Nanodrop2.0: Thermo Fisher Scientific, U.S.
Water bath tank: PolyScience Company, U.S.
Electronic balance: Shanghai Precision Instrument Co., Ltd.
Cell incubator: Sanyo Company, Japan
Embodiment 1 Method for knocking out UTX gene
1. Breeding of Mice
A C57BL/6J mouse, a UTX flox mouse and an Albcre tool mouse were all purchased from the Model Animal Research Center of Nanjing University. Experimental mice were raised in a SPF-level animal room in strict accordance with the requirements set forth in the Regulations for the Administration of Experimental Animals. The environment conformed to a biological rhythm of 12-hour diurnal cycle and the experimental mice were free to eat food and drink water. Breeding cages were configured according to a manner of one male mouse matched with two female mice, toes were numbered 7 days to 14 days after the mice were born, and tails were cut to identify a genotype. The male and female mice were raised separately in different cages 21 days after birth. Wild UTXf/f mice of the same age and the same sex were used as control mice.
2. Genotype Identification of Mice
1) Extraction of Tail DNA
2) Genotype Identification of Mice by PCR
Using the extracted tail DNA as a template, the Taq enzyme reagent from Vazyme Company was added into 8-tube strips according to the following table, evenly mixed and centrifuged.
The mixture was placed in a PE2400 PCR instrument for PCR amplification, and PCR cycle parameters were as follows:
Primer sequences were as follows:
10 μl of PCR products and 1.0% to 2.0% agarose/ethidium bromide were taken for gel electrophoresis, and analysis was carried out by a UVP gel density scanner and an analysis software (UVP, Inc.) thereof; and target strip with a corresponding size could be seen positively.
3. A female UTXf/f mouse (purchased from Jackson Laboratory in U.S.) was mated with a male albcre mouse (purchased from Jackson Laboratory in U.S.) to obtain a male UTXf/y:albcre mouse through gene identification by the method in the step 2; and the male mouse was further mated with the female UTXf/f mouse to obtain a female UTXf/f:albcre mouse or a male UTXf/y:albcre mouse, and then a subsequent experiment was performed. In view that the UTX is an X sex chromosome linkage gene, and the female mouse contains two alleles, but the male mouse contains only one allele, so the female UTXf/f:albcre knockout mouse was mainly used in the research herein. The mouse genotype was identified by PCR (see
A knockout efficiency was identified by qRT-PCR and Western blot respectively.
4. Serum collection and blood biochemical determination of mouse
Results of blood biochemical indexes of the UTXf/f:albcre mouse were shown in Table 1. The UTXf/f:albcre mouse had significantly higher blood cholesterol and triglyceride levels in a fasting state, but had no significant difference in a blood glucose level; wherein the cholesterol mainly comprised LDL-C and HDL-C, while the results showed that the LDL-C contents in the blood of the UTXf/f:albcre mouse were increased significantly, but ratios of the HDL-C contents were decreased significantly after being corrected by a total cholesterol content (Chol) or the LDL-C although the HDL-C was also increased to some extent.
The overexpression efficiency of the UTX in the HepG2 liver cell was detected.
00066 After the UTX was over-expressed in the HepG2 liver cells, glucose was used to stimulate for 24 h, and then the cell supernatant was collected for triglyceride detection.
1. Acquisition of UTX Overexpression Mouse
To induce hyperlipidemia and non-alcoholic fatty acid liver disease (NAFLD), 6-week-old mice were fed with a high-fat diet (HFD, fat content 60%; Research Diets, New Brunswick, N.J.). 2 months later, purified pAdEasy-UTX adenoviruses (1.5*108 plaque-forming units per mouse) were transduced into mice through tail-vein injection to specifically upregulate UTX expression in liver. Three days after the injection, all mice were killed and the livers were collected for further analysis.
2. Serum Collection and Blood Biochemical Determination of the UTX Overexpression Mouse
1. H&E Staining
Once UTX overexpression mouse were executed, liver tissues were harvested. A small piece of liver was cut and submerged in 4% paraformaldehyde. The sample was sent to Service Biology (Wuhan, Hubei, China) for hematoxylin and eosin (H&E) staining to detect lipid content.
2. Hepatic Triglyceride Content
Once UTX overexpression mouse were executed, liver tissues were harvested, frozen immediately in liquid nitrogen, and stored at −80° C. for subsequent analysis. A small piece of liver were homogenerated in PBS by the ratio of 1:9 (g:ml), and cell supernatant was collected. Automatic biochemical analysis was performed to detect extracellular triglyceride content in the laboratory of Nanjing Maternity and Child Health Care Hospital.
After the UTX was over-expressed in hyperlidemia and NAFLD mice,
Various embodiments of the invention have been described above, and the description above is exemplary, but not exhaustive, and the invention is not limited to the disclosed embodiments. Many modifications and variations are apparent to those of ordinary skills in the art without departing from the scope and spirit of the described embodiments.
This application is a divisional application of U.S. Ser. No. 16/554,589 filed on 28 Aug. 2019 that claims priority to Chinese Patent Application Ser. No. CN2019102480171 filed on 28 Mar. 2019.
Number | Date | Country | |
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Parent | 16554589 | Aug 2019 | US |
Child | 17513483 | US |