Following the confirmation of the significantly increased levels of oxidative stress and inflammation in the mice exposed to seven days of CSR, the probiotic was able to increase the antioxidant capacity of the brain to potentially limit associated oxidative damage.
In addition, markers of inflammation were reduced and altered hormone levels were restored in this group, when compared to the controls.
“Probiotic supplementation can represent a viable strategy to counteract oxidative stress and inflammation related to sleep loss, thus possibly limiting its negative consequences on health and well-being,” the Italian researchers conclude.
They add: “The possibility of counteracting the deleterious effects of sleep deprivation with probiotics is intriguing and could be relevant for populations who by necessity have a disrupted sleep schedule, such as shift workers.”
The significance of sleep
The modern-day world has created a public health epidemic in the form of insufficient sleep, with CSR mainly being attributed to professional commitments and lifestyle habits. Yet, sleep is critical for both our physical and mental health, reflected in its occurrence taking up a third of a human’s lifetime.
It has been observed that CSR can lead to impaired brain function, increasing the risk of neuropsychiatric disorders, whilst also leading to cardiovascular disease and metabolic conditions. This follows increasing evidence that sleep deprivation can increase concentrations of inflammatory markers within the body and brain to cause low-grade inflammation, whilst also increasing cellular damage caused by increased reactive oxygen species (ROS).
Studies have reported significant dysbiosis in those with CSR, suggesting a link with sleep and the gut health. With a vast amount of recent evidence highlighting the importance of a healthy gut microbiome for our immunity and inflammation, there has been a similar interest in the use of probiotics to ameliorate these symptoms in those with CSR.
Thereby, the researchers conducted the present study to investigate the ability of probiotics administered to mice to improve symptoms of oxidative stress and inflammation caused by CSR exposure.
The probiotic (SLAB51) utilised consisted of eight different live bacterial strains: Streptococcus thermophilus DSM 32245, Bifidobacterium lactis DSM 32246, Bifidobacterium lactis DSM 32247, Lactobacillus acidophilus DSM 32241, Lactobacillus helveticus DSM 32242, Lactobacillus paracasei DSM 32243, Lactobacillus plantarum DSM 32244, and Lactobacillus brevis DSM 27961.
The study involved eight-week-old mice, with a probiotic group being fed the strains whilst a control group were fed water over a period of eight weeks. These two groups were further split into CSR groups (CSR-w n=7, CSR-p n=7) who were exposed to seven days of CSR, and normal sleep groups (S-w n=7, S-p, n=7).
Levels of oxidation were measured in the proteins, lipids, and DNA, in addition to hormone and cytokine levels. Microglia morphology and density was also determined in the mouse cerebral cortex.
It was observed that CSR resulted in significant oxidative stress and inflammation within the exposed mice, whilst gut-brain axis hormones were also altered.
Following SLAB51 administration, the oxidative damage resulting from CSR was significantly limited, due to an increased antioxidant capacity of the brain. In addition, inflammation was reduced, and gut-brain axis hormones were regulated in this group, compared to the controls.
“Our study provides direct support to the growing evidence that probiotics can attenuate oxidative stress and inflammation in the brain and at systemic level via the gut-brain axis,” the report summarises, drawing attention to prior studies supporting the role of sleep deprivation plays in increasing these levels.
“The mechanisms through which probiotics improve health are numerous and include the modulation of the host immune system, modification of the intestinal microbiota, protection against physiological stress, pathogen antagonisms, and improvement of the barrier function of the gut epithelium,” the researchers highlight.
Despite the significant findings present in the study, further RCTs are required using a larger human population to further examine the potential benefits of probiotics for reversing the damaging effects of sleep deprivation.
“Probiotics Supplementation Attenuates Inflammation and Oxidative Stress Induced by Chronic Sleep Restriction”
Yadong Zheng, Luyan Zhang, Laura Bonfili, Luisa de Vivo, Anna Maria Eleuteri and Michele Bellesi