Constant light exposure alters gut microbiota and short‐/medium‐chain fatty acids and aggravates PCOS‐like traits in HFD‐fed rats

Abstract

Objective This study investigated the effects of constant light exposure on polycystic ovary syndrome (PCOS)‐like endocrine and metabolic changes in high‐fat diet (HFD)‐fed rats and to elucidate the related microbiotic mechanisms. Methods A total of 32 female Sprague‐Dawley rats were divided into four groups (n = 8 each): rats on a normal chow diet with standard light‐dark cycle, rats on a normal chow diet with constant light exposure, rats on an HFD with standard light‐dark cycle, and rats on an HFD with constant light exposure. After 16 weeks of treatment, changes in anthropometric parameters, estrous cycle, hormone profiles, ovarian pathology, and gut microbiota and short‐/medium‐chain fatty acids in colon contents were assessed. Results Constant light exposure aggravated PCOS‐like phenotypes in HFD‐fed rats, such as hyperandrogenism, disrupted estrous cycle, and polycystic ovaries. Additionally, constant light exposure and an HFD synergized to decrease α‐diversity of gut microbiota, create a reduced abundance of Ruminococcus genus, and create an increased abundance of Firmicutes and the Firmicutes/Bacteroidetes ratio. In HFD‐fed rats, the group with constant light exposure had an increase in propionate acid and a decrease in total medium‐chain fatty acids in colon contents compared with the standard light‐dark cycle group. Conclusions Constant light exposure causes gut dysbiosis, alters production of short‐ and medium‐chain fatty acids, and aggravates PCOS‐like traits in HFD‐fed rats.

Association between mobile phone addiction, sleep disorder and the gut microbiota: a short-term prospective observational study

“…Although the Firmicutes/Bacteroidetes (F/B) ratio as a marker for assessing gut microbiota health remains a topic of debate, accumulating evidence, including our own research, supports its potential utility. Our study revealed a positive correlation between MPA and an increased F/B ratio, consistent with previous investigations conducted by Yue et al (2022) and Hong et al (2020) . In their respective studies, mice were exposed to standard light–dark cycles and constant light for 16 weeks, with the constant light group exhibiting a higher relative abundance of Firmicutes and a lower relative abundance of Bacteroidetes .…”

Central blockage of sympathetic nerves inhibits the abnormal vital signs and disturbance of the gut microbiota caused by continuous light exposure

“…Moreover, we found that the Prevotella genus was the main feature discriminating bacterial communities in the CI group. Yue et al also found that Prevotella was enriched in the group of rats with continuous light exposure and positively correlated with serum testosterone and IL-6 levels [ 45 ]. Li et al showed that Prevotella is a common pre-hypertensive and hypertensive microbial signature that may play an important role in hypertension by triggering an inflammatory response [46].…”