Hyposalivation in Down Syndrome: Calcium Signaling and a New Paradigm of Preventive Care

Reduced salivary flow is a recognized clinical feature of Down syndrome, but its underlying biological mechanisms have long remained unclear. A new preclinical study now offers a molecular explanation — and potentially, a therapeutic direction.

Researchers using an established mouse model of Down syndrome confirmed a significant reduction in salivation along with inflammatory changes in the salivary glands. The key finding: impaired calcium signaling in salivary gland cells — a process necessary for normal saliva secretion. Human cells from individuals with Down syndrome cultured in the laboratory demonstrated the same calcium signaling defect, suggesting the mechanism extends beyond animal models.

«Many aspects of Down syndrome are well documented,» explains Professor Rodrigo Lacruz, senior author and professor of molecular pathobiology at the College of Dentistry at New York University. «However, the molecular basis of hyposalivation and its connection to periodontal disease remained unknown. Our work demonstrates that calcium signaling dysfunction may be the missing link.»

Multifactorial picture of pathological changes

The study revealed several interconnected pathological changes. In addition to impaired calcium signaling, the salivary glands showed signs of compromised mitochondrial function and increased inflammatory activity — consistent with the enhanced immune activation observed in individuals with Down syndrome. Analysis of the oral and intestinal microbiota revealed dysbiosis with elevated levels of succinate-producing bacteria — a metabolic byproduct previously associated with periodontal inflammation.

Together, these findings suggest that hyposalivation, microbial dysbiosis, and impaired metabolism may converge to accelerate the progression of periodontal disease in this population.

Pilocarpine: prospects and required caution

Treatment with pilocarpine — a parasympathomimetic agent used in Sjögren syndrome — significantly improved salivary flow and reduced one of two markers of gingival inflammation in the mouse model. However, Professor Lacruz emphasized the need for careful further investigation.

«The genetic background of Down syndrome is distinctive: over 300 genes on chromosome 21 are hyperexpressed. Pilocarpine may therefore have unintended effects on pathways not affected in other conditions. We are exploring alternative therapeutic approaches to proceed cautiously and avoid adverse effects on other systems.»

Clinical conclusions

Although the study is at the preclinical stage, its findings underscore the importance of proactive preventive strategies in patients with Down syndrome: regular assessment of salivary function, careful periodontal monitoring, and preventive care protocols. The work also signals potential future therapeutic targets aimed at restoring salivary gland function, rather than simply managing the consequences of disease.

The study «Dysregulated calcium signaling underlies hyposalivation and microbial dysbiosis in Down syndrome» was published on July 1, 2026, in the journal Cell Reports.

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