Researchers from the University of North Carolina School of Dentistry's Oral Health Institute used total RNA from gingival biopsy samples collected from 20 patients in four groups: five nonobese (body mass index [BMI] < 30 kg/m2) people with a healthy periodontium, five nonobese people with periodontitis, five obese (BMI > 30 kg/m2) people with a healthy periodontium, and five obese people with periodontitis.
Two microRNA species were up-regulated among obese individuals with a healthy periodontium, two were up-regulated in nonobese subjects with periodontal disease and in the presence of periodontal disease and obesity, and nine were significantly up-regulated.
The data are consistent with the concept that miRNA that are induced by chronic nutritional stress leading to obesity may also nonparsimoniously modulate inflammatory pathways within periodontal tissues and affect disease expression, the researchers concluded.
"The expression of specific microRNA species in obesity provides new insight into possible mechanisms of how risk factors might modify periodontal inflammation and may represent novel therapeutic targets," stated JDR Editor William Giannobile in a news release.
While these data could represent a mechanistic breakthrough in understanding the modulatory effects of obesity on periodontal tissue destruction, "reproducibility of these findings is needed in larger and well-characterized cohorts," noted Francesco D'Aiuto, DMD, PhD, and Jean Suvan, from the University College London Eastman Dental Institute, in a related editorial.