Protective effects of polyunsatutared fatty acids supplementation against testicular damage induced by intermittent hypobaric hypoxia in rats

Abstract

BackgroundIntermittent hypobaric hypoxia (IHH) induces changes in the redox status and structure in rat testis. These effects may be present in people at high altitudes, such as athletes and miners. Polyunsaturated fatty acids (PUFA) can be effective in counteracting these oxidative modifications due to their antioxidants properties. The aim of the work was to test whether PUFA supplementation attenuates oxidative damage in testis by reinforcing the antioxidant defense system. The animals were divided into four groups (7 rats per group): normobaric normoxia (~750 tor; pO2 156 mmHg; Nx); Nx + PUFA, supplemented with PUFA (DHA: EPA = 3:1; 0.3 g kg−1 of body weight per day); hypoxic hypoxia (~428 tor; pO2 90 mmHg; Hx) and, Hx + PUFA. The hypoxic groups were exposed in 4 cycles to 96 h of HH followed by 96 h of normobaric normoxia for 32 days. Total antioxidant capacity (FRAP) and lipid peroxidation (malondialdehyde, MDA) in plasma and reduced (GSH)/oxidized glutathione (GSSG) ratio, tissue lipid peroxidation (TBARS) and antioxidant enzymes activity were assessed at the end of the study in testis. Also, SIRTUIN 1 and HIF-1 protein expression in testis were determined.ResultsIHH increased lipid peroxidation in plasma and HIF-1 protein levels in testis. In addition, IHH reduced FRAP levels in plasma, antioxidant enzymes activities and SIRTUIN 1 protein levels in testis. PUFA supplementation attenuated these effects, inducing the increases in FRAP, in the antioxidant enzymes activity and HIF-1 levels.ConclusionsThese results suggest that the IHH model induces a prooxidant status in plasma and testis. The molecular protective effect of PUFA may involve the induction of an antioxidant mechanism.

Sperm forward motility is negatively affected by short-term exposure to altitude hypoxia

“…In particular, Castillo et al . showed that intermittent hypobaric hypoxia induces a pro‐oxidant state in plasma and rat testes through increased lipid peroxidation and reduced in antioxidant mechanisms (Castillo et al ., ). Also, Farias and colleagues asserts that, in testis and epididymis, intermittent hypobaric hypoxia (IHH) induced lipid peroxidation (TBARS production) with a reduction in glutathione reductase activity and a significant decrease in epididymal sperm count (Farias et al ., ).…”

Pharmacological approaches in either intermittent or permanent hypoxia: A tale of two exposures

“…After this period, male fertility normalizes, with normal seminal count parameters, motility, form and maturity of spermatozoids [43]. The findings of our group related with the effects of ICH on male fertility has taken us to consider the specific activation of "ICH" pathways, that in conjunction with other variables such as temperature, vascularization and apoptosis, would be involved in the adverse effects on fertility of individuals intermittently exposed to HA [37,44].…”

“…One potential alternative is to incorporate food with high antioxidant levels to the diet in those people exposed to HA, and we have shown that this may have a positive effect in the protection of cells facing oxidative stress [45]. We described, in rats exposed to ICH, that testicles and epididymis shown an increase in lipid peroxidation markers and lower GSH levels compared with normoxic normobaric animals, and that these effects were fully reverted with concomitant administration of ascorbic acid, blueberry extracts or Ω3 chronic supplementation [44,45,46]. Indeed, these protective effects can be supported by the induction of enzymatic and non-enzymatic antioxidant defense systems.…”

Mechanisms of Cardiovascular Protection Associated with Intermittent Hypobaric Hypoxia Exposure in a Rat Model: Role of Oxidative Stress

“…After euthanasia, cardiac tissue was frozen in liquid nitrogen and stored at −80 °C until use. After tissue homogenization, Western blot (WB) analyses were performed for the protein expression of 4 HNE; specific antibody ab46545 (Abcam Laboratories, Cambridge, UK), Nitrotyrosine (NT, anti-NT 05-233, Millipore, Billerica, MA, USA) as described previously [ 16 , 62 ].…”

“…However, the mechanism that support the precondition effects of acute IH on myocardial and vascular function have not been well characterized. The aim of this work is to describe the responses on cardiac and vascular function, structure and biomechanical properties after four cycles of intermittent hypobaric hypoxia (IHH) and the association with pro oxidant markers and ROS sources in a well-established rat model [ 15 , 16 ].…”