The Effect Of Diet-induced Paternal Obesity To The Testicle And Spermatozoa Of F₀ And F₁ Male Mice

Objection:With the incidence of obesityis increasing,and the previous study showing a major effect of paternal obesity on metabolic health and reproductive health.Therefore,we investigated the effect of diet-induced paternal obesity on the ultrastructure of testicular tissue and spermatozoa of F₀ and F₁ male mice.Method:1.At 4 weeks of age,100 male mice?C57BL/6?were fed either a control diet?n=25?and an high-fat diet?n=75?for 12 weeks and total body weight was measured weekly.2.The GTT?Intraperitoneal glucose tolerance test?and the ITT?Intraperitoneal insulin tolerance test?were performed in the founder?F₀?male breeders after 6 and 12 weeks under the assigned diet.At 16 weeks of age,10 F₀ mice were then mated with 8 week-old normal females from an independent line to produce F₁ offspring.3.Testiculars and epididymals were removed respectively from the F₀ male mice of 16week-old,then preparated the ultrathin slices and the sperm suspension,to observe and analyse the sperm quality parameter by the SQA?sperm quality analyzer?.4.The sperm morphology of normal and obese mice was observed and analyzed by IMSI sperm amplification system.5.Observe the ultrastructural changes of spermatozoa and testis by the transmission electron microscopy.6.The GTT and the ITT were performed in the F₁ male when they were 10 week-old and16 week-old.7.For the F₁ male generation,we will proform to do the same experiments as the F₀ male mice does.Result:Compared with the F₀ mice in the common diet group:1.The F₀ generation mice in the high-fat diet group increased body weight by 58.19%?P<0.05?after continuous feeding for 12 weeks,reaching the body weight standard of obese mice.2.The results of GTT and ITT showed that the glucose homeostasis,fasting insulin levels,or insulin sensitivity were not altered in the founder male mice when they were exposed to high-fat diet for 6 and 12 weeks.Compared with F₀ mice of the normal group:1.The testicular coefficient?-33.06%,P<0.05?and epididymal coefficient?-31.78%,P>0.05?decreased in the F₀ obesity group.2.The VAP?-44.22%,P<0.05?,VSL?-49.34%,P<0.05?,PR?-21.05%,P<0.05?,and sperm density?-41.63%,P<0.05?were significantly decreased,the sperm abnormality rate?+3.55%,P<0.05?was significantly increased.3.The F₀ generation of obese male mice sperm hook,irregular head,long neck bending,cytoplasmic droplets,abnormal cervical deformity and curly head,neck and body deformity.4.In the testicles of F₀ obese male mice,the number of Leydig cells were reduced,the number and morphology of mitochondria in the cytoplasm had no significant difference;the seminiferous tubule became thinner,the number of spermatogenic cells decreased,and derangement,basal membrane of the seminiferous tubules were abnormal,the electronic density of spermatogonia cytoplasm were sparse and vacuolization,the gap appeared among cells,the mitochondrial abnormalities,swelling and vacuolization degeneration in Sertoli cells,abnormal sperm head nucleolar staining quality and acrosome,and the number of mature sperm decreased inside the lumen.Microtubule were damaged,and without the complete 9+2 structure.5.The sperm structure of the male mice of the F₀ generation was abnormal,and the sperm plasma membrane was swollen and damaged.Compared with F₁ mice of the normal group:1.The F₁ males increased total body weight?+3.46%;P<0.05?without the high-fed diet.2.The male mice in the F₁ generation had no glucose tolerance and insulin resistance.3.The testicular coefficient?-10.57%,P<0.05?and epididymal coefficient?-4.35%,P>0.05?decreased in the F₁ obesity group.4.The VAP?-48.27%,P<0.05?,VSL?-58.62%,P<0.05?,PR?-16.58%,P<0.05?,and sperm density?-27.85%,P<0.05?were significantly decreased,the sperm abnormality rate?+3.41%,P<0.05?was significantly increased.5.The sperm of the F₁ male mice had double heads and the same type of sperm abnormality as that of the F0 generation.6.In the F₁ obese male mice,the number of Leydig cells were reduced,the number and morphology of mitochondria in the cytoplasm had no significant difference;the seminiferous tubule became thinner,the number of spermatogenic cells decreased,and derangement,basal membrane of the seminiferous tubules were abnormal,the electronic density of spermatogonia cytoplasm were sparse and vacuolization,the gap appeared among cells,the mitochondrial abnormalities,swelling and vacuolization degeneration in Sertoli cells,abnormal sperm head nucleolar staining quality and acrosome,and the number of mature sperm decreased inside the lumen.7.The sperm structure of the F₁ male mice was abnormal,with the head bending,the nucleolus fixation,the gap between the acrosome and the apical membrane breakage.Conclusions:1.The obesity induced by high fat diet could lead to abnormal sperm morphology in F₀and F₁ mice.2.The obesity induced by high fat diet could lead to abnormal semen parameters in F₀and F₁ mice,reduce sperm vitality,density,and reduce sperm quality.3.The obesity induced by high fat diet could induce abnormal ultrastructure of testicles and spermatozoa in F₀ generation and F₁ generation mice,which may cause reproductive decline in male mice.