Oral microbiota in aging and diseases

RIG-I-driven CDKN1A stabilization reinforces cellular senescence

The innate immune signaling network follows a canonical format for signal transmission. The innate immune pathway is crucial for defense against pathogens, yet its mechanistic crosstalk with aging processes remains largely unexplored. Retinoic acid-inducible gene-I (RIG-I), a key mediator of antiviral immunity within this pathway, has an enigmatic role in stem cell senescence. Our study reveals that RIG-I levels increase in human genetic and physiological cellular aging models, and its accumulation drives cellular senescence. Conversely, CRISPR/Cas9-mediated RIG-I deletion or pharmacological inhibition in human mesenchymal stem cells (hMSCs) confers resistance to senescence. Mechanistically, RIG-I binds to endogenous mRNAs, with CDKN1A mRNA being a prominent target. Specifically, RIG-I stabilizes CDKN1A mRNA, resulting in elevated CDKN1A transcript levels and increased p21Cip1 protein expression, which precipitates senescence. Collectively, our findings establish RIG-I as a post-transcriptional regulator of senescence and suggest potential targets for the mitigation of aging-related diseases.

Deciphering the influence of gut and oral microbiomes on menopause for healthy aging

Menopause is characterized by the cessation of menstruation and a decline in reproductive function, which is an intrinsic component of the aging process. However, it has been a frequently overlooked field of women's health. The oral and gut microbiota, constituting the largest ecosystem within the human body, are important for maintaining human health and notably contribute to the healthy aging of menopausal women. Therefore, a comprehensive review elucidating the impact of the gut and oral microbiota on menopause for healthy aging is of paramount importance. This paper presents the current understanding of the microbiome during menopause, with a particular focus on alterations in the oral and gut microbiota. Our study elucidates the complex interplay between the microbiome and sex hormone levels, explores microbial crosstalk dynamics, and investigates the associations between the microbiome and diseases linked to menopause. Additionally, this review explores the potential of microbiome-targeting therapies for managing menopause-related diseases. Given that menopause can last for approximately 30 years, gaining insights into how the microbiome and menopause interact could pave the way for innovative interventions, which may result in symptomatic relief from menopause and an increase in quality of life in women.

The Common Hallmarks and Interconnected Pathways of Aging, Circadian Rhythms, and Cancer: Implications for Therapeutic Strategies

The intricate relationship between cancer, circadian rhythms, and aging is increasingly recognized as a critical factor in understanding the mechanisms underlying tumorigenesis and cancer progression. Aging is a well-established primary risk factor for cancer, while disruptions in circadian rhythms are intricately associated with the tumorigenesis and progression of various tumors. Moreover, aging itself disrupts circadian rhythms, leading to physiological changes that may accelerate cancer development. Despite these connections, the specific interplay between these processes and their collective impact on cancer remains inadequately explored in the literature. In this review, we systematically explore the physiological mechanisms of circadian rhythms and their influence on cancer development. We discuss how core circadian genes impact tumor risk and prognosis, highlighting the shared hallmarks of cancer and aging such as genomic instability, cellular senescence, and chronic inflammation. Furthermore, we examine the interplay between circadian rhythms and aging, focusing on how this crosstalk contributes to tumorigenesis, tumor proliferation, and apoptosis, as well as the impact on cellular metabolism and genomic stability. By elucidating the common pathways linking aging, circadian rhythms, and cancer, this review provides new insights into the pathophysiology of cancer and identifies potential therapeutic strategies. We propose that targeting the circadian regulation of cancer hallmarks could pave the way for novel treatments, including chronotherapy and antiaging interventions, which may offer important benefits in the clinical management of cancer.

Correlation Between the Oral Microbiota and Sports Practice: A Systematic Review

The impact of sports on oral health has been the subject of extensive investigation, with the majority of studies indicating a deterioration in oral health. However, the composition of the oral microbiota in athletes and its impact remains unclear. The objective of this review is to investigate the potential correlation between athletic activity and alterations in the oral microbiota. A comprehensive electronic search was conducted up to November 2024 across three different databases (PubMed, the Cochrane Library, and Scopus) with the objective of identifying studies that evaluate the association between oral microbiota and physical activity. Two independent blinding review authors were involved in study selection, data extraction, and bias assessment using the National Institutes of Health's (NIH) study quality assessment tools. A total of 147 records were screened, and five eligible studies were included. Recent studies have demonstrated that individuals who engage in regular physical activity exhibit distinctive oral microbial composition in comparison to those with sedentary lifestyles or low levels of physical activity. Three studies have demonstrated that the athlete's oral microbiota is modified, with an increase in the genera Rothia, Stenotrophomonas, and Veillonella, and a decrease in the genus Gemella. The Streptococcus genus is often modified in athletes according to four studies. This review provided an analysis of the scientific evidence indicating that the oral microbiota of athletes is modified. But to date, there is no scientific evidence to clearly determine the impact of sports on these variations. More homogeneous studies with the limitation of bias are needed to better understand the link between sports and oral microbiota.