Conversations around fertility are tricky. Did you know obesity-related reproductive issues are becoming increasingly common in men? Now, a study by The Journal of Neuroscience has confirmed how obesity is an enemy of male fertility. Per the study, there is emerging evidence that male obesity negatively impacts fertility and is linked to ‘reduced testosterone, lower sperm count, and diminished libido’. Also read | Decoding the rapid decline in sperm count
Obesity linked to low testosterone, sperm count
The research used mice fed on a high-fat diet to mimic human obesity and found that it caused chronic changes in brain connections. The study found evidence that obesity weakens communication between the brain circuits that control both feeding and reproduction, potentially explaining the link between obesity and reproductive issues in men.
While it is well-known that obesity lowers testosterone in men, which impacts various functions like muscle mass, cognition, and reproductive health, the exact mechanisms by which obesity causes these changes are not fully understood. This study aimed to understand how chronic obesity alters brain circuitry to produce these effects in obese men, who often suffer from low testosterone levels, reduced sperm count, and poor sperm quality.
What are the findings?
The researchers found that obesity caused significant changes in the brain’s reproductive circuitry. In obese mice, LH pulse frequency was reduced, leading to lower testosterone levels and reduced sperm counts. While the reproductive system retained its ability to function normally under direct stimulation, the chronic effects of obesity suppressed the activity of kisspeptin neurons, which are essential for triggering the release of GnRH and LH.
Why the findings matter
“A long-term goal of my research is to identify the molecular and cellular mechanisms that regulate reproductive function, which is necessary for the survival of the species,” said corresponding author Djurdjica Coss, a professor of biomedical sciences and associate vice chancellor for research at the University of California, Riverside School of Medicine.
Djurdjica added, “My research is significant to individuals struggling with unexplained infertility. Currently, 1 in 8 couples experience infertility and require assisted reproductive technologies to have a child. It is also important for the survival of endangered species, whose preservation depends on reproductive assistance, and for our food supply, as agricultural animals increasingly suffer from infertility due to modern farming practices. The studies in my lab may help identify new treatments and strategies to alleviate conditions that contribute to the rising infertility rates in both humans and animals.”