Objective: To investigate high-fat diet-induced obesity-triggered testicular cell senescence and endoplasmic reticulum stress.
Methods: We randomly and equally divided 10 four-week-old male C57BL/6J mice into a control and a high-fat group, the former fed with a diet of 10% fat content while the latter with a diet of 60% fat content to establish an obesity model. After eight weeks of feeding, we observed the pathological changes in the testis tissue of the mice by HE staining, detected the serum T content by ELISA, measured the telomere length in the testis cells by RT-PCR, and examined the activity of senescence-associated β-galactosidase (SA-β-gal) by histochemical staining. Using RT-qPCR and Western blot, we determined the protein and mRNA expressions of the cell senescence markers p16 and p21 as well as the protein expressions of the endoplasmic reticulum stress markers GRP78 and CHOP in the testis tissue.
Results: Compared with the controls, the animals of the high-fat group showed a 45% increase in the body weight, disordered structure of the spermatogenic cells, reduced level of serum T and shortened telomere length of the testis cells (P < 0.01). The mRNA and protein expressions of p16 and p21 were dramatically higher in the high-fat than in the control group (P<0.01), so were the intracellular SA-β-gal activity and the protein expressions of CHOP and GRP78 (P<0.01).
Conclusion: High-fat diet-induced obesity triggers testicular cell senescence and endoplasmic reticulum stress in male mice.
Keywords: high-fat diet; obesity; cellular senescence; endoplasmic reticulum stress; male reproduction; mouse.