Next generation sequencing of oral microbiota in Type 2 diabetes mellitus prior to and after neem stick usage and correlation with serum monocyte chemoattractant-1

Abstract Introduction Oral microbiome impacts health and disease. T2DM and periodontitis are associated. Neem ( Azadiracta indica ) has antibacterial activity against oral microbiota. Objectives To characterize oral microbiota (OMB) in saliva samples of T2DM patients by Next generation sequencing. To analyze MCP-1 levels among the T2DM patients before and after a month of neem stick usage as a toothbrush. Materials and methods Blood and saliva samples were collected from adult T2DM patients before and after the neem stick usage. Metagenomic sequencing was performed on saliva samples targeting V6 region of 16s rRNA. Serum MCP-1 levels were determined using a quantitative sandwich Human MCP-1 standard ABTS development kit (Peprotech, USA). Results The profile of oral microbiota of T2DM patients (n = 24) consists of Streptococcus (95.8%) counts ranging from 2644 to 27,214, Veillonella (72.2%, counts 25–19,709, Neisseria (87.5%) 453–33,445), Rothia (63.6%, 233–6734), Actinomycetes (25%, 161–3730), Fusobacterium (21%, 2252–21,334), and Pigmentiphaga (12.5% 3–16,644). Oral microbiota in healthy controls (n = 10), consists of Streptococcus (26.1%), Veillonella (21.9%), Neisseria (16.9%), Haemophilus (10.7%), Actinomycetes (2.6%), Rothia (3.1%), Oribacterium (1.7%). Post neem samples showed drastic reduction in the load of bacteria which was statistically significant. The mean serum MCP-1 before the use of neem stick was 265.18 ± 79.44 (range 141.6–980.5 pg/ml) and dropped to 33.6 ± 7.35 after a month of neem stick usage (P value > 0.001). Conclusion OMB of T2DM patients and healthy controls were similar, however bacterial loads were significantly higher in T2DM patients. Use of neem stick has a statistically significant reduction on bacterial loads and MCP-1 levels in T2DM patients.