Epigenetic Modifications in Alternative Splicing of LDLR pre-mRNA on Hypercholesterolemia Following Aerobic Exercise Training
Abstract
1. Introduction
2. Results
2.1. Expression of LDLR Splice Variants and LDL Cholesterol Concentration in Humans with Different Levels of Habitual Physical Activity
2.2. The Effects of High-Cholesterol Diet and Exercise Training on Weight and Lipid Levels in Mice
2.3. The Effects of High-Cholesterol Diet and Exercise Training on Liver Tissue in Mice
2.4. The Effects of High-Cholesterol Feeding and Exercise Training on Alternative Splicing of LDLR Pre-mRNA in Mice
2.5. The Effect of Cholesterol on the Alternative Splicing of LDLR Pre-mRNA in HepG2
2.6. The Effect of Hypercholesterolemia on Histone Modification in HepG2
2.7. Transfection on HepG2 Cell: H3-K36me3 Regulated the Alternative Splicing of LDLR Pre-mRNA
2.8. Transfection on HepG2 Cell: MRG15 Regulated the Alternative Splicing of LDLR Pre-mRNA
3. Discussion
3.1. Physically Active Lifestyle Prevents the Overexpressed Alternative Splicing of LDLR Pre-mRNA
3.2. Aerobic Exercise Training Reverses High-Cholesterol Diet-Induced Alternative Splicing
3.3. The Effect of Histone Modification on Alternative Splicing of LDLR Pre-mRNA
3.4. The Effect of Genomic Recruitment on Alternative Splicing of LDLR Pre-mRNA
3.5. Study Limitations and Perspectives
4. Materials and Methods
4.1. Human Subjects
4.2. Assessment of Blood Plasma Lipid Levels
4.3. Human Blood RNA Extraction
4.4. Animals and Exercise Training Protocol
4.5. Hematoxylin–Eosin Staining (H&E Staining)
4.6. Cell Culture
4.7. Plasmids and Transfection
4.8. RNA Analysis
4.9. Chromatin Immunoprecipitation (CHIP)
4.10. Statistical Analysis
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Normal Group (n =10) | Exercise Training Group (n = 10) | High-Cholesterol Group (n = 10) | |
---|---|---|---|
Men vs. Women | 7 vs. 3 | 7 vs. 3 | 8 vs. 2 |
Age (year) | 21 ± 2 | 22 ± 1 | 22 ± 1 |
Weight (kg) | 73.4 ± 2.8 | 68.7 ± 3.7 * | 90.2 ± 4.3 *,# |
Height (m) | 1.72 ± 0.03 | 1.75 ± 0.02 | 1.73 ± 0.03 |
BMI (kg/m2) | 24.7 ± 0.5 | 22.4 ± 0.4 | 30.5 ± 2.1 *,# |
MVPA (minutes/week) | 406 ± 46 | 916 ± 86 * | 129 ± 42 *,# |
LDL (mmol/L) | 1.67 ± 0.39 | 0.98 ± 0.39 | 3.16 ± 0.94 *,# |
TC (mmol/L) | 3.73 ± 0.52 | 3.15 ± 0.43 | 6.96 ± 0.58 *,# |
TG (mmol/L) | 1.02 ± 0.25 | 0.85 ± 0.49 | 1.88 ± 0.65 |
HDL (mmol/L) | 1.51 ± 0.25 | 2.52 ± 0.30 * | 1.45 ± 0.6 # |
AIP | −0.18 ± 0.16 | −0.53 ± 0.27 * | 0.12 ± 0.30 *,# |
LDLR-∆Exon4 | 1.00 ± 0.01 | 0.72 ± 0.09 * | 4.32 ± 0.89 *,# |
LDLR-∆Exon12 | 1.00 ± 0.01 | 0.47 ± 0.33 * | 2.96 ± 1.03 *,# |
Gene | Forward Primer | Reverse Primer |
---|---|---|
Mouse LDLR primers used in RT-PCR | ||
β-Actin | CATCCGTAAAGACCTCTATGCCAAC | ATGGAGCCACCGATCCACA |
LDLR-14(+) | GGTGAACTGGTGTGAGACAACA | AGGAGTACTGGGAGCTGAGAGA |
LDLR-14(−) | CCAATCGACTCACGGGTTCA | ACAGTGTCGACTTCTCTAGGC |
Human LDLR primers used in RT-PCR | ||
β-Actin | CTCCATCCTGGCCTCGCTGT | GCTGTCACCTTCACCGTTCC |
LDLR-4(+) | TGTCCCCCCAAGACGTGCTCC | CGCAGTTTTCCTCGTCAGATT |
LDLR-4(−) | TCAGCTGTGGGGGCCGTGTC | CAGGTGGCCACAGGACAGC |
LDLR-12(+) | ATCACCCTAGATCTCCTCAGTG | GCACTGAAAATGGCTTCGTT |
LDLR-12(−) | AATGGCATCACCCTAGGACAA | ATCCTCTGGGGACAGTAGGTT |
Mouse LDLR primers used in CHIP assays | ||
GAPDH | AGGTCGGTGTGAACGGATTTG | TGTAGACCATGTAGTTGAGGTCA |
P | GGTCCTACCCCCCAAACCAAG | GAAGTATGCGAAGCCCCCTCC |
A | TTTGATGATGGATTTGGAAGGTT | TGACAGGTGACAGACACTAGGGA |
B | AGCCCCCAAGACGTGCTCCCA | GCCTCGCCGTCACAGACCCAG |
C | GGCCCCAACAAGTTCAAGTG | GGCTCATCCGACCAGTCCTG |
D | TGACCCCTTTCTTCTGCCTCAGC | TGTCCTCCTCTTTACGCCCTTGG |
E | GTGCCAATCGACTCACGGGTT | CGGGGACAAGAGGTTTTCAGC |
F | TCTGGCTTACTCTGAAGATGGG | AACTGACAACATTTGATGACGG |
G | CAATGGTGGTTGCCAGTACCT | ACTTGTGCCCCTACCTGTGAG |
H | ATTCTCATTTTATTTATTCATTT | TGGTATTTCGTTTTCTCCTTCTA |
I | ATGCAAGCACTTAGGTGGCG | ACCTCCTCCTAGTCACAACCA |
Human LDLR primers used in CHIP assays | ||
GAPDH | CCATCTTCCAGGAGCGAGAT | CTAAGCAGTTGGTGGTGCAG |
P | ATCACCCCACTGCAAACTCC | GATCACGACCTGCTGTGTCC |
A | AGTTCCAGTGCCAAGACGG | CAAAGGGGACTCACAGCACG |
B | CTGAGTCCTGGGGAGTGGTC | AACCCGAAGAGGTAGCACCA |
C | AGTGCTCATAGCAGTGCTGG | TCACCGTGTGAAGTCTCCCA |
D | TGACGAGGAAAACTGCGGTA | GGAAATCCACTTCGGCACCTA |
E | TGTCGCCCTGACGAATTCCA | GCAGCCAACTTCATCGCTC |
F | TCCCGTTGGGAGGTCTTTTCC | AACCAAGAGTGCCTCCCCAT |
G | CCTGAAGGTTTCCCTCTTTCTT | TGCAGTGAGCTACGATT |
H | GCCTCTCCAGGTGCTTTTCT | GCTGCAGTGAGCTACGATT |
I | ATGCAAGCACTTAGGTGGCG | ACCTCCTCCTAGTCACAACCA |
J | TGTCATCTTCCTTGCTGCCT | TGACATCGGAACCTGTGAGG |
K | CACAACCACCCGACCTGTTC | AAGGGAGTGAGGACGACACC |
L | CACAAGGGGTTTAGGGTAGGT | CCAGAGGGAGACGGTGAGTA |
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Zhao, J.; Yan, P.; Pang, Y.; Dong, Y.; Shi, X. Epigenetic Modifications in Alternative Splicing of LDLR pre-mRNA on Hypercholesterolemia Following Aerobic Exercise Training. Int. J. Mol. Sci. 2025, 26, 4262. https://doi.org/10.3390/ijms26094262
Zhao J, Yan P, Pang Y, Dong Y, Shi X. Epigenetic Modifications in Alternative Splicing of LDLR pre-mRNA on Hypercholesterolemia Following Aerobic Exercise Training. International Journal of Molecular Sciences. 2025; 26(9):4262. https://doi.org/10.3390/ijms26094262
Chicago/Turabian StyleZhao, Jinfeng, Peirun Yan, Yana Pang, Yuankun Dong, and Xiangrong Shi. 2025. "Epigenetic Modifications in Alternative Splicing of LDLR pre-mRNA on Hypercholesterolemia Following Aerobic Exercise Training" International Journal of Molecular Sciences 26, no. 9: 4262. https://doi.org/10.3390/ijms26094262
APA StyleZhao, J., Yan, P., Pang, Y., Dong, Y., & Shi, X. (2025). Epigenetic Modifications in Alternative Splicing of LDLR pre-mRNA on Hypercholesterolemia Following Aerobic Exercise Training. International Journal of Molecular Sciences, 26(9), 4262. https://doi.org/10.3390/ijms26094262