# Diacerein Downregulates Nfkb, Induces ALP Activity and Inhibits Osteoblast Apoptosis in Alveolar Bone of Rats with Periodontitis

## TL;DR

Diacerein reduces inflammation and prevents bone cell death in rats with periodontitis, helping protect alveolar bone.

## Contribution

This study shows diacerein's novel role in downregulating Nfkb and inhibiting osteoblast apoptosis in periodontitis.

## Key findings

- Diacerein reduced TNF-α and IL-1β immunoexpression while increasing ALP activity and bone area.
- Diacerein decreased Nfkb1 expression and increased Bmp2 and IL-10 in periodontitis-affected rats.
- Diacerein significantly reduced osteoblast apoptosis compared to the control group.

## Abstract

Objectives: We evaluated the effect of diacerein, an anti-inflammatory drug, on the activity and survival of alveolar bone osteoblasts in rats with periodontitis. Methods: The rats with periodontitis received diacerein (PDG) or saline solution (PSG) for 7, 15 and 30 days. In gingiva samples, Nfkb1 and Bmp2 gene expressions were evaluated, and maxillae were processed for light and transmission electron microscopy. Results: In PDG, the tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) immunoexpression decreased in parallel with the increase in alkaline phosphatase (ALP) and bone area over time. At 15 and 30 days, Nfkb1 expression decreased in PDG compared to PSG, whereas at 30 days, the Bmp2 expression was greater in PDG than in PSG. Immunofluorescence for IL-10, an anti-inflammatory cytokine, was greater in PDG than in PSG at 15 and 30 days. In PSG, the significant increase in the number of TUNEL-positive osteoblasts was accompanied by the presence of osteoblasts with condensed chromatin nuclei or caspase-3-immunolabelled osteoblasts. In contrast, the number of TUNEL-positive osteoblasts was significantly lower in PDG than in PSG specimens at all time points. Conclusions: Therefore, the diacerein-induced TNF-α and IL-1β inhibitory effect caused Nfkb1 downregulation and, hence, prevented apoptosis in osteoblasts. The increased ALP activity and IL-10 in PDG indicate that diacerein mitigates periodontitis impact on alveolar bone in rat molars.