Application of selenoprotein F as iron homeostasis supplement

Abstract

The invention provides application of selenoprotein F as a target in organism iron metabolism homeostasis, the selenoprotein F is adopted as a drug target for maintaining iron metabolism balance of an organism, the iron metabolism function of the organism is improved by up-regulating expression of the selenoprotein F, and the effect of improving nerve injury is achieved. The invention provides a new molecular mechanism for promoting iron metabolism disorder by expression reduction of selenoprotein F, and provides new strategies and standards for improving treatment of a series of diseases caused by iron metabolism disorder.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine technology, and in particular to the application of selenoprotein F as an iron homeostasis supplement. Background Art

[0002] Iron is the most abundant transition metal in the brain and is involved in many important physiological and biochemical reactions in organisms. An important function of iron is to transport oxygen in hemoglobin and myoglobin. In addition, iron is also involved in mitochondrial respiration, DNA synthesis and the biosynthesis of neurotransmitters. However, free iron ions can easily interact with oxygen, triggering a cascade of chemical reactions, leading to the production of free radicals and reactive oxygen species. These substances will attack other substances in the cell, such as chromosomes, proteins and organelles, and ultimately cause cell damage or even death.

[0003] Both excess and deficiency of iron can lead to impaired brain function, so strict regulation of iron metabolism is crucial. There is a system in the cell to maintain iron homeostasis: transferrin (TF) and transferrin receptor (TFR) are responsible for transporting iron from serum into cells, ferritin heavy chain 1 (FTH) and ferritin light chain store iron in cells, and iron transporter (FPN) is responsible for expelling excess free iron from cells. The dynamic balance of these proteins constitutes the iron homeostasis of cells. But once this balance is broken, it will easily induce cell death.

[0004] Selenium (Se) is an essential trace element in the human body and is particularly important for maintaining good health. After various forms of selenium enter the human body, its main physiological function is mainly exerted through selenoproteins (proteins containing selenocysteine). Selenoprotein is a special protein that contains the 21st amino acid - selenocysteine. Selenoprotein F (SELENOF, a 15kDa selenoprotein, also known as Sep15) is an endoplasmic reticulum resident protein. However, the biological function of selenoprotein F is still unclear. Therefore, the present invention explores the potential connection between selenoprotein F and iron metabolism-related proteins by silencing or knocking out selenoprotein F in normal mouse models and cell models. Summary of the invention

[0005] The first aspect of the present invention provides the use of selenoprotein F as an iron homeostasis supplement.

[0006] The second aspect of the present invention provides the use of selenoprotein F in the preparation of an iron homeostasis supplement.

[0007] Furthermore, the application concentration of the selenoprotein F at the cellular level is 2ng / μL-6ng / μL of the plasmid containing the selenoprotein F expression sequence.

[0008] The third aspect of the present invention provides an iron homeostasis supplement comprising selenoprotein F and pharmaceutically acceptable excipients.

[0009] The fourth aspect of the present invention provides the use of selenoprotein F as the sole active ingredient in the preparation of a drug for improving cell death caused by iron metabolism homeostasis in HT22 cells and HEK293 cells, wherein the concentration of the drug and the concentration of the selenoprotein F expression sequence plasmid are 2ng / μL-6ng / μL.

[0010] Furthermore, the medicine also includes pharmaceutical excipients.

[0011] The fifth aspect of the present invention provides the use of selenoprotein F in the preparation of drugs for treating diseases caused by iron metabolism disorders.

[0012] Furthermore, selenoprotein F is used as a ferroptosis inhibitor in the preparation of therapeutic drugs for diseases caused by iron metabolism disorders.

[0013] Furthermore, the disease is a neurodegenerative disease or cerebral stroke.

[0014] Furthermore, the drug contains a pharmaceutically acceptable carrier or excipient.

[0015] The sixth aspect of the present invention provides the use of selenoprotein F as a drug target for screening drugs for treating cell death caused by imbalance of iron metabolism homeostasis in HT22 cells and HEK293 cells, wherein the drug includes a promoter of selenoprotein F expression.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] In the present invention, it is found through experiments that knocking out selenoprotein F in normal mice can cause learning and memory disorders and neuron reduction in mice. It is also found that iron metabolism-related proteins in selenoprotein F knockout mice are disordered, and these changes may be the cause of the learning and memory disorders and neuron reduction in mice after selenoprotein F deficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The results of the effect of selenoprotein F deficiency on the learning and memory ability of mice are shown in the figure: A. Cognitive index; B. Escape latency; C. The time that mice spend in the target quadrant or platform at 24 hours and 72 hours; (n=9, one-way ANOVA followed by Tukey post hoc test, *p<0.05, **p<0.01) D. Western blot results of PSD95 protein in the brain of mice after selenoprotein F knockout. (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05)

[0019] Figure 2The results of selenoprotein F affecting the expression of proteins related to iron metabolism are shown in the figure: A. Selenoprotein F deficiency promotes FAC-induced HT22 cell death; B. Selenoprotein F interacts with TFR and UGGT; C. Western blot results of TFR and FPN in HT22 cells after 24h of selenoprotein F knockdown and 24h of FAC treatment; D. Western blot results of TFR, FPN and FTH proteins in HEK293 cells 24h after selenoprotein F plasmid transfer. (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05)

[0020] Figure 3 The results of the effect of selenoprotein F deficiency on iron homeostasis in mice are shown in the figure: A. Mouse liver iron level; B. Mouse serum iron level; C. Mouse brain iron level; (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05, **p<0.01) D Western blot results of TFR, FPN and FTH proteins in the mouse brain after selenoprotein F knockout. (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05, **p<0.01)

[0021] Figure 4 The results of selenoprotein F deficiency aggravating the disorder of iron levels are shown in the figure: A. Fe levels in FAC-induced HT22 cells under selenoprotein F knockdown treatment measured by a multifunctional microplate reader 2+ The content of Fe in HT22 cells was detected by immunofluorescence. 2+ (Scale bar = 20 μm); C. Using isotope Fe 57 HT22 cells were treated with selenoprotein F silencer and Fe in the culture medium was detected 24 hours after treatment. 57 (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05); D. using isotope Fe 57 HT22 cells with selenoprotein F silenced were treated and Fe in the culture medium without Fe57 was detected after Fe57 treatment. 57 (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05). 57 HT22 cells with selenoprotein F silenced were treated, and the Fe57 content in the cells was detected 24 hours after treatment (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05)

[0022] Figure 5The figure shows that the lack of selenoprotein F aggravates the learning and memory impairment of 3×Tg-AD mice. In the figure: A. Activity trajectory of mice; B. Time spent by mice in the target quadrant or platform at 24 hours and 72 hours; C. Nissl staining results of mouse brain; (n=6, one-way ANOVA followed by Tukey post hoc test, *p<0.05, **p<0.01) D. Western blot results of APP, Aβ1-42, TFR, FPN and FTH proteins in the brain of 3×Tg-AD mice after silencing selenoprotein F gene expression. (n=3, one-way ANOVA followed by Tukey post hoc test, *p<0.05). DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] All animal treatments and experiments used in this invention were performed in strict accordance with the institutional guidelines for the use of laboratory animals of Shenzhen University and were approved by the Animal Ethics and Welfare Committee of Shenzhen University (approval number AEWC-20140615-002) on June 15, 2014. All procedures were performed in accordance with the ethical standards of the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health.

[0025] Example 1 Animal Experiment

[0026] In this experiment, 4-month-old C57B6N mice with selenoprotein F knockout were selected as model animals, 3×Tg-AD transgenic mice and C57B6N were used as control groups. 3×Tg-AD mice were purchased from Jax Laboratories in the United States, and C57B6N mice were purchased from Weitong Lihua in China.

[0027] In this experiment, C57B6N mice and corresponding selenoprotein knockout mice were randomly divided into 2 groups of 12 each, namely the corresponding model group (referred to as C57-NC), high iron feeding group (C57-Fe), selenoprotein F knockout group (KO-NC) and high iron feeding selenoprotein F knockout group (KO-Fe). 3×Tg-AD mice (NC-AD) and corresponding selenoprotein knockout silenced mice (SH-AD) were selected to form a group of 11 mice each. The selenoprotein F knockout group mice were injected with adeno-associated viruses that silenced selenoprotein F in the CA3 region of the mouse hippocampus. All mice were housed in a controlled environment with a 12-hour light-dark cycle, a temperature of 23±2℃, and free access to standard laboratory food and water. The high-iron group was fed with high-iron feed for 3 consecutive months, and the selenoprotein F silenced group was experimented 3 months after the virus injection.

[0028] Table 1 Mouse model information

[0029]

[0030] The mice in each group were subjected to the following experiments:

[0031] (1) Detection of brain iron levels in mice by inductively coupled plasma-mass spectrometry (ICP-MS)

[0032] Inductively coupled plasma mass spectrometry (ICP-MS) is a special mass spectrometry technique that can be used to determine the proportion of each element in the tissue. The cortex of each group was weighed and recorded, and 4 ml of concentrated nitric acid was added to each and digested by microwave digestion. 2 O is diluted to 10 ml for determination. After setting up the blank control and standard, the determination is carried out, and the data is collected and analyzed.

[0033] Conclusion: The concentration of iron ions in the brain, liver and serum of mice was detected by ICP-MS technology. The results showed that the iron ion concentration in the brain of KO-NC group mice was significantly higher than that of C57-NC group, and the degree of increase was greater after iron feeding, while the iron ion concentration in the brain of normal mice fed with iron did not change significantly, and even showed a downward trend; however, the opposite result was found in serum, which was higher in C57-NC group than in KO-NC group, and higher in C57-Fe group than in C57-NC group. In the liver, the iron ion concentration in KO-Fe group was found to be higher than that in C57-Fe. The above results indicate that the accumulation of iron in the brain of mice may be increased after the loss of selenoprotein F.

[0034] Furthermore, the expression levels of iron metabolism-related proteins in the mouse brain were examined by immunoblotting, and it was found that TFR was significantly upregulated and FPN and FTH were significantly downregulated in both KO groups compared with both C57 groups, while high-iron feeding did not seem to have a different effect on iron metabolism-related proteins in the two KO groups. The above results indicate that selenoprotein F deficiency may impair the ability of mice to regulate iron homeostasis, so there was no significant difference between KO mice under high-iron conditions, but there was a difference between normal groups.

[0035] The above results indicate that the lack of selenoprotein F may cause an increase in iron ion levels in the brain, thereby aggravating possible ferroptosis in the brain. This phenomenon is caused by the disorder of iron metabolism caused by the lack of selenoprotein F.

[0036] (2) Morris water maze behavior test

[0037] The Morris water maze experimental apparatus is mainly a circular pool, divided into 4 quadrants. A digital camera is set up directly above to track the activity trajectory of the mouse, and its field of view can cover the entire open field of view. Before the experiment, it is necessary to ensure that the environment is quiet enough. Young adult mice are placed in different starting positions in a circular pool (22 cm in diameter) filled with water (20-21°C, made opaque by adding milk powder). The mice are trained to use distant visual cues to find an underwater platform (1 cm in diameter) 8 cm below the water surface in the northeast quadrant of the pool (the destination quadrant). Spatial cues appear on the four walls around the pool at a distance of 0.5m. In all trials, the observer was in the room and was always in the same position (behind the curtains around the setting). Each mouse was trained in 3 quadrants per day for five days. On the sixth day, a 24-hour spatial memory ability test was performed, the platform was removed, and the mice were allowed to swim freely in the pool for 60s, and the time in the destination quadrant and the platform position was recorded. On the eighth day, a 72-hour spatial memory ability test was performed. The platform was removed and the mice were allowed to swim freely in the pool for 60 seconds. The time spent in the target quadrant and the platform position was recorded.

[0038] Conclusion: In order to study the effect of selenoprotein F deficiency on the learning and memory ability of mice, the Morris water maze test was performed after 2 months of high-iron diet treatment. Compared with C57, the escape latency of KO group mice showed a difference on the second day, indicating that the spatial memory ability of mice was reduced after selenoprotein F was knocked out ( Figure 1A); There was no significant difference between the C57-NC group and the C57-Fe group, but the escape latency of KO-Fe was longer than that of KO-NC, which shows that iron feeding itself did not seriously damage the spatial memory ability of mice, but under the condition of selenoprotein F deficiency, it would aggravate the spatial memory ability of selenoprotein F-deficient mice; In addition, in the 24-hour target phenomenon time detection, it was found that the KO group was much shorter than the normal group, and KO-Fe also performed worse. At the same time, a similar phenomenon was found in the 72-hour target phenomenon time detection ( Figure 1 D). This indicates that the lack of selenoprotein F will damage the spatial memory ability of mice. At the same time, the mice themselves will not have obvious changes under high iron treatment, but it will aggravate the memory damage of mice under the lack of selenoprotein F. (n=8, *p<0.05)***p<0.001)( Figure 1 D).

[0039] In addition, novel object recognition was used to detect the exploration tendency and avoidance regulation ability of mice in new environments after selenoprotein F knockout and high iron treatment. Mice need to distinguish between relatively familiar objects and new objects that they have never been exposed to. Once the memory is biased, it will lead to memory confusion and inability to distinguish between new and old objects. Compared with the C57-NC group, the KO-NC group and the KO-Fe group had a significantly decreased discrimination rate for new and old objects (n=8, **p<0.01), indicating that their curiosity about new things and tendency to explore new things were weaker, among which the KO-Fe group had a significantly lower discrimination rate for new and old objects than the KO-NC group ( Figure 1 E). The results showed that selenoprotein F knockout impaired cognitive ability in mice, and high iron treatment exacerbated the impairment.

[0040] In summary, the lack of selenoprotein F will affect the cognitive function and learning and memory ability of mice, and this phenomenon may be caused by the aggravated iron metabolism disorder in the brain of mice after the lack of selenoprotein F.

[0041] (3) Novel object behavior experiment

[0042] During the first 3 days of experimental training or testing, the experimental mice were stroked for 1 minute every day to avoid stimulating the mice to eliminate the unfamiliarity with the tester. On the first day, the mice were placed in the test box for 5 minutes to adapt. On the second day, two identical objects A and B were placed in the test box and placed at the left and right ends of one wall. Consistently, the mice were placed in the box to explore for 5 minutes. After the third day, object A or B was replaced with another new object C, and the mice were allowed to explore for 5 minutes. The contact between the mice and the two objects was recorded, including the number of contacts with the nose, mouth or forepaws and the distance to the object 2 exploration time within 2-3cm. After the experiment, the inner wall and the bottom of the box should be thoroughly cleaned with 75% alcohol to avoid residual odor.

[0043] Conclusion: Silencing of selenoprotein F in the hippocampus aggravates AD pathology in 3×Tg-AD mice

[0044] Brain iron accumulation often occurs in AD patients, which is very similar to the phenomenon of selenoprotein F knockout mice. Therefore, by injecting selenoprotein F silencing virus into the CA3 region of the hippocampus of 3×Tg-AD, we explored whether the reduction of selenoprotein F would affect the AD pathology of mice. From the results of Morris behavior, it was found that the time spent in the target quadrant of the silencing group mice (SH-AD) was significantly lower than that of the control group (NC-AD) at 24 hours. At the same time, the changes in the number of neuronal cells in the brain region of 3×Tg-AD mice were evaluated by Nissl staining. Among them, the number of Nissl bodies in the cortex, CA1 region, and DG region of the silencing group mice (SH-AD) was significantly less than that of the control group (NC-AD). Western blot detection showed that the level of Aβ1-42 in mice increased significantly after silencing selenoprotein F. At the same time, the level of TFR increased significantly, while the levels of FPN and FTH decreased significantly.

[0045] In summary, silencing selenoprotein F in the mouse hippocampus aggravates the AD pathology of 3×Tg-AD mice, and this phenomenon may be caused by the aggravation of iron metabolism disorders in the mouse brain caused by silencing selenoprotein F.

[0046] (4) Protein extraction and protein blotting

[0047] With reference to the instructions of each reagent, lysis buffer (including ice-cold RIPA lysis buffer and protease and phosphatase inhibitors) was used to prepare lysate for protein lysis in proportion. Protein concentration was determined using a BCA protein assay kit (Cat#23235, Thermo Scientific, USA) according to the manufacturer's instructions. According to the molecular weight of the target protein, a suitable SDS-PAGE gel was selected for electrophoresis. The loading amount per well was 40-60ug. Then, the protein band was electrotransferred to polyvinylidene fluoride (PVDF, Cat#ISEQ00010, Millipore, USA). After transfer, the PVDF membrane was removed, soaked with 1X TBST, and then moved to a box containing a fast blocking solution (Beyotime), shaken on a decolorizing shaker at room temperature for 0.5-1h or blocked overnight at 4°C. The PVDF membrane was then removed from the blocking solution, placed in a primary antibody diluent, and incubated overnight at 4°C. The next day, the primary antibody dilution was recovered, and the PVDF membrane incubated with the primary antibody was placed in 1X TBST and washed 3 times at room temperature on a decolorizing shaker for 10-15 minutes each time. The secondary antibody dilution (Cat#ab288151, Abcam, USA) was prepared in the same way and contacted with the PVDF membrane. After incubation at room temperature for 1-2 hours, the secondary antibody dilution was discarded. The PVDF membrane incubated with the secondary antibody was then placed in 1X TBST and washed 3 times at room temperature on a decolorizing shaker for 10-15 minutes each time. After the above was completed, the PVDF membrane was evenly immersed in the developer and developed in the Tanon-5200 chemiluminescent development system.

[0048] ImageJ or quantityone analysis software was used to adjust the images obtained after development to the most appropriate contrast, and the grayscale values ​​of protein bands and fluorescent images were analyzed. Graphpad Prism 8 software was used to analyze the data, and one-way ANOVA was performed, with significant differences at p < 0.05.

[0049] Conclusion: Western blot detection also found that the level of synaptic-related protein PSD95 in KO group mice was significantly lower than that in NC group, and the expression level of PSD95 in C57-NC and C57-Fe groups did not change significantly. This also proves at the molecular level that knocking out selenoprotein F will reduce the level of synaptic-related proteins in mice, thereby causing damage to learning and memory function.

[0050] Example 2 Cell experiment

[0051] (1) Cell culture and treatment

[0052] HT22 and HEK293 cells were used for cell experiments. The cells were cultured in a medium containing 50% Dulbecco's modified Eagle's medium (DMEM) (Gibico, USA) supplemented with 50% Opti-MEM, 5% fetal bovine serum, 0.5% penicillin and streptomycin, and with or without 200 μg / mL G418 (Invitrogen). The cells were incubated at 37°C and 5% CO 2 After the cells grew close to confluence, they were treated with / without selenoprotein F silencing adenovirus in DMEM (1% fetal bovine serum) for 24 hours, then treated with / without 100 μM ammonium ferric citrate for 24 hours and then used for subsequent experiments. The selenoprotein F overexpression plasmid was transfected into the HEK293 cell line and cultured normally for 24 hours before use in subsequent experiments.

[0053] (2) Co-immunoprecipitation

[0054] Co-Immunoprecipitation is a classic method for studying protein interactions based on the specific interaction between antibodies and antigens. It is an effective method to determine the physiological interaction between two proteins in intact cells. Collect HT22 cells in a 24cm2 culture flask, add 1ml lysate, add protease inhibitors (100:1), collect lysate, centrifuge (4℃, 113000rpm, 10mins), collect supernatant and place on ice for use. Magnetic beads (Protein G Magnetic Beads, MCE) are premixed with anti-sep15 antibody at 4℃ for 2 hours in advance. Add lysate to magnetic beads and place in a flip mixer for incubation (4℃ overnight), magnetic separation, discard supernatant, add 100μL 1×SDS-PAGE Loading Buffer to magnetic beads, mix evenly, and heat at 95℃ for 5mins. Separate magnetic beads, collect supernatant, and perform SDS-PAGE detection.

[0055] Conclusion: After silencing selenoprotein F in the HT22 cell line and inducing with ferric ammonium citrate (FAC) for 24 hours, cell viability detection showed that silencing selenoprotein F did not cause cell death. FAC induction caused a significant decrease in the viability of cells with silencing selenoprotein F, indicating that silencing selenoprotein F would aggravate the death phenomenon induced by FAC, and only ferroptosis inhibitors could restore the phenomenon of cell death, indicating that FAC-induced cell death was ferroptosis. First, the interaction between selenoprotein F and iron metabolism-related proteins such as protein receptor (TFR) and iron transporter (FPN) was examined by immunoprecipitation. The results showed that selenoprotein F interacted with TFR, indicating that selenoprotein F may affect cellular iron metabolism by regulating TFR. Western blotting detection showed that the level of FPN in cells decreased significantly after silencing selenoprotein F, while the level of TFR did not change significantly. These results indicate that silencing selenoprotein F may affect the homeostasis of iron metabolism and cause cell death. At the same time, selenoprotein F was overexpressed in the HEK293 cell line. Western blot detection showed that after selenoprotein F was overexpressed, the level of TFR decreased significantly, and the levels of FPN and FTH increased significantly, indicating that the expression of selenoprotein F may promote the increase in the expression levels of FPN and FTH, while inhibiting the expression level of TFR. In summary, changes in the expression level of selenoprotein F may affect the iron homeostasis of cells, and this effect may be caused by changes in proteins such as TFR, FPN, and FTH.

[0056] Iron homeostasis is one of the important homeostasis to maintain normal physiological activities of humans, especially in the brain, many major diseases will appear metal ion homeostasis disorder phenomenon. In the present invention, reducing or increasing the expression level of selenoprotein F will affect the expression of iron metabolism-related proteins, and selenoprotein F will also interact with TFR. Various studies have shown that the aggregation of intracellular iron can induce cell death and lead to cognitive impairment. Therefore, it is speculated that selenoprotein F may affect the body's iron homeostasis by regulating the expression level of iron metabolism-related proteins, and ultimately affect the body's learning and memory function.

[0057] Metal ion deposition often occurs in neurodegenerative diseases and stroke. More and more researchers believe that neurodegenerative diseases are closely related to iron metabolism disorders. In the present invention, it is first found that knocking out selenoprotein F in normal mice can cause learning and memory disorders and neuron loss in mice. It is also found that iron metabolism-related proteins in selenoprotein F knockout mice are disordered, and these changes may be the cause of the learning and memory disorders and neuron loss in mice after selenoprotein F deficiency.

[0058] Metal ion deposition often occurs in AD patients. An increasing number of researchers believe that AD and ferroptosis are closely linked, and they believe that the death of neurons in AD patients may be due to ferroptosis. In this study, knocking down the expression level of selenoprotein F in the hippocampus of 3×Tg-AD mice aggravated the learning and memory impairment and neuronal loss of mice, and the level of Aβ, an AD pathological indicator, also increased. It was also found that iron metabolism-related proteins in 3×Tg-AD mice showed changes similar to those in selenoprotein F knockout mice, and these changes may be the reason for the aggravation of the pathology of 3×Tg-AD mice after the loss of selenoprotein F.

[0059] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Application of selenoprotein F as a supplement for iron metabolism homeostasis.

2. Application of selenoprotein F in the preparation of iron metabolism homeostasis supplements.

3. An iron metabolism homeostasis supplement, characterized in that: Contains selenoprotein F and pharmaceutically acceptable excipients.

4. Use of selenoprotein F as the sole active ingredient in the preparation of a drug for improving cell death caused by imbalance of iron metabolism homeostasis in HT22 cells and HEK293 cells, characterized in that: The application is to transfer a plasmid containing a selenoprotein F expression sequence into cells, and the plasmid concentration is 200ng / μL-600ng / μL.

5. The use according to claim 4, characterized in that: The medicine also includes pharmaceutical excipients.

6. Application of selenoprotein F in the preparation of drugs for treating diseases caused by disorders of iron metabolism.

7. Application of selenoprotein F as an inhibitor of iron metabolism disorders in the preparation of therapeutic drugs for diseases caused by ferroptosis.

8. The use according to claim 7, characterized in that: The disease is a neurodegenerative disease.

9. The use according to claim 7, characterized in that: The medicine contains a pharmaceutically acceptable carrier or excipient.

10. Use of selenoprotein F as a drug target for screening drugs for treating cell death caused by imbalance of iron metabolism homeostasis in HT22 cells and HEK293 cells, characterized in that: The drug includes a promoter for selenoprotein F expression.

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