Manchette-acrosome disorders and testicular efficiency decline observed in hypercholesterolemic rabbits are recovered with olive oil enriched diet

Abstract

High-fat diet is associated with hypercholesterolemia and seminal alterations in White New Zealand rabbits. We have previously reported disorders in the development of the manchette-acrosome complex during spermiogenesis and decreased testicular efficiency in hypercholesterolemic rabbits. On the other hand, olive oil incorporated into the diet improves cholesterolemia and semen parameters affected in hypercholesterolemic rabbits. In this paper, we report the recovery—with the addition of olive oil to diet—from the sub-cellular mechanisms involved in the shaping of the sperm cell and testicular efficiency altered in hypercholesterolemic rabbits. Using morphological (structural, ultra-structural and immuno-fluorescence techniques) and cell biology techniques, a reorganization of the manchette and related structures was observed when olive oil was added to the high-fat diet. Specifically, actin filaments, microtubules and lipid rafts—abnormally distributed in hypercholesterolemic rabbits—were recovered with dietary olive oil supplementation. The causes of the decline in sperm count were studied in the previous report and here in more detail. These were attributed to the decrease in the efficiency index and also to the increase in the apoptotic percentage in testis from animals under the high-fat diet. Surprisingly, the addition of olive oil to the diet avoided the sub-cellular, efficiency and apoptosis changes observed in hypercholesterolemic rabbits. This paper reports the positive effects of the olive oil addition to the diet in the recovery of testicular efficiency and normal sperm shaping, mechanisms altered by hypercholesterolemia.

Dietary Cholesterol and Lipid Overload: Impact on Male Fertility

“…By using either olive oil (as a source of monounsaturated fatty acids (MUFA)) or krill oil (for n -3 PUFA), they showed that olive oil partially neutralized the negative effects of a high-fat diet on sperm quality, increasing gamete mobility, reducing oxidative stress (lipoperoxidation), and slightly improving mitochondria function [55]. These data are in accordance with beneficial effects of olive oil demonstrated on spermatozoa from hypercholesterolemic rabbits, as described above [17, 19]. In mice, data on dietary lipid supplementation and its effect on sperm function are rare.…”

“…These defects were shown to be due to an abnormal interaction between the manchette-acrosome complex and the membrane microdomains. Here, the authors demonstrated that a dietary intake of 7% olive oil combined with HCD could restore a normal phenotype [19]. Unfortunately, the authors did not propose any hypothesis on how olive oil dietary supplementation could act to restore a normal phenotype.…”

Is a Ketogenic Diet Superior to a High-Fat, High-Cholesterol Diet Regarding Testicular Function and Spermatogenesis?

“…An observational study demonstrated that underweight and overweight individuals have a lower semen quality, in terms of total sperm number and total motile sperm count ( 33 ). Adverse effects of a high fat ( 34 ) or high cholesterol intake ( 35 ) on the structure and function of the testes have been reported. In this study, HFC consumption induced pathological damage in testicular tissue and impaired spermatogenesis in terms of reduction of the germinal epithelium thickness, fewer mature spermatozoa, and a poor semen quality.…”

A chronic high-fat diet causes sperm head alterations in C57BL/6J mice

“…Recently, we informed that hypercholesterolemic rabbits showed sperm head defects under a HFD [3, 4]. These spermatogenic defects were prevented by reducing dietary fat and supplementing with olive oil [4, 29]. This and other evidences [1, 13, 30] suggest that systemic oxidative stress and inflammation may play a key role in the accumulation of cholesterol in the testicles, as well as cytoskeleton disorganization during spermiogenesis.…”

“…An abnormal head shape can be caused by an anomalous shape of the nucleus due to the ectopic position of the manchette's microtubules [39]. This probably causes an alteration in the anchorage of the microtubules (as seen in rabbits), which probably results in the abnormal shape of the sperm heads [4, 29].…”