• Male diabetic rats exhibit multiple reproductive deficiencies, including reduced sperm count, decreased motility, decreased viability, and lower testosterone.
  • Treatment with curcumin and vitamin E ameliorates reproductive deficits in male diabetic rats. 
  • Treatment lowers oxidative stress levels and the amount of DNA damage in sperm cells.  

Males with diabetes are often susceptible to several physiological abnormalities, one of which is impaired fertility. This happens, in part, due to the increased presence of oxidative stress-inducing compounds – reactive oxygen species (ROS). In light of this, scientists have explored the utilization of potent natural antioxidants to ameliorate diabetes-related infertility. 

Now, in a preprint released in Toxicology Reports, researchers from Urmia University of Medical Sciences in Iran report that combining curcumin and vitamin E, two well-established antioxidants, reverses multiple reproductive deficits in male diabetic rats. Moreover, the antioxidant combo successfully lowered oxidative stress and boosted testosterone – the primary male sex hormone responsible for the development of secondary sexual characteristics and the maintenance of reproductive function, including sperm production and fertility.  

Curcumin and Vitamin E Enhance Sperm Health 

Sperm quality and function are paramount for successful fertilization and the subsequent attainment of a healthy pregnancy. For this to occur, several sperm parameters need to be in check, namely sperm count, viability, and motility – the ability of sperm to move coordinately through the reproductive tract to reach and fertilize an egg. 

Rahimi and colleagues explored these parameters in male diabetic rats and found that they exhibited reduced sperm count, decreased viability, and impaired motility. However, following treatment with curcumin and vitamin E, all sperm parameters were recovered, highlighting the protective effects of this antioxidant combo on reproductive health. 

Notably, following treatment, the male diabetic rats also displayed significantly higher levels of testosterone than untreated rats. Given testosterone’s vital role in sperm health, the results suggest that curcumin and vitamin E mitigate diabetes-related infertility by rescuing declining testosterone levels.  

(Rahimi et al., 2023 | Toxicology Reports) Curcumin and vitamin E increase sperm viability and sperm motility.  Diabetic male rats treated with curcumin and vitamin E (E+Curcumin) exhibit greater sperm viability (left) and motility (right) than untreated rats (diabetes) and those treated with only curcumin or vitamin E. 

Curcumin and Vitamin E Quench Oxidative Stress

Safeguarding our genetic blueprints (DNA) from oxidative stress holds significance not only in the context of delaying the onset of age-related diseases but also in preserving the integrity of sperm. Studies have shown that increased levels of oxidative stress, commonly observed in diabetes patients, can lead to DNA fragmentation (breaking) in sperm cells, which can trigger sperm cell death.  

The investigators proceeded to measure the antioxidative effects of curcumin and vitamin E and found that treatment effectively quenched oxidative stress. Furthermore, male diabetic rats treated with the antioxidant combo also exhibited fewer sperm cells with fragmented DNA than untreated rats. Taken together, the study’s findings demonstrate that curcumin and vitamin E attenuate diabetes-related infertility by decreasing oxidative stress and DNA damage in sperm cells. 

(Rahimi et al., 2023 | Toxicology Reports)  Curcumin and vitamin E reduce  DNA damage in sperm cells.  Excluding control rats, diabetic male rats treated with curcumin and vitamin E have the lowest percentage of sperm cells with DNA damage. 

Harnessing Natural Antioxidants For Healthy Aging

Oxidative stress is intrinsically linked to accelerated aging, and studies continue to highlight natural antioxidants as powerful tools to enhance our body’s resilience to its harmful effects. Among these, vitamin E and curcumin stand out as two compounds renowned for their remarkable antioxidative properties. Beyond their ability to extinguish oxidative stress, natural antioxidants also play a major role in regulating inflammation, another hallmark of age-related diseases. Antioxidants also support the immune system and help protect multiple organs of the body. Accordingly, studies have shown that curcumin protects the aging brain and muscles, attenuating age-related cognitive decline and increasing muscle endurance and strength in mice. Natural antioxidants, including cucurmin, are profoundly abundant in various plant-based sources such as fruits, vegetables, nuts, and herbs. With this in mind, incorporating antioxidant-rich foods represents a proactive and accessible means of protecting our organs against oxidative stress.