Relationship between salivary melatonin levels and periodontal status in diabetic patients

Abstract

: Among other functions, melatonin exerts both antioxidative and immunoregulatory roles. The indoleamine is secreted in the saliva, although its role into the mouth is not known. Diabetic patients frequently display oral cavity pathologies such as periodontal disease (PD), an inflammatory disease coursing with an increase in free radical production. Thus, we compared the degree of PD and interleukin‐2 (IL‐2) levels with melatonin concentrations in plasma and saliva of diabetic patients. A total of 43 diabetic patients (20 with type I and 23 with type II diabetes) and 20 age‐ and sex‐matched controls were studied. Dental and medical history of all patients was in accordance with the criteria of the WHO. The periodontal status was evaluated by the Community Periodontal Index (CPI). Plasma and salivary melatonin levels were determined by specific commercial radioimmunoassays, and plasma IL‐2 was measured using a commercial enzyme‐linked immunosorbent assay kit. Diabetic patients had plasma and saliva melatonin levels of 8.98 ± 7.14 and 2.70 ± 2.04 pg/mL, respectively. These values were significantly lower (P < 0.001) than those obtained in plasma and saliva of controls (14.91 ± 4.75 and 4.35 ± 0.98 pg/mL, respectively). Plasma and salivary melatonin concentrations show a biphasic response in diabetic patients. Melatonin decreased in patients with a CPI index of 2, and then increased reaching highest levels in patients with a CPI index of 4. By contrast, IL‐2 levels decreased from CPI index 1 to 4. The results indicate that, in diabetic patients, the presence of a marked impairment of the oral status, as assessed by the CPI index, is accompanied by an increase in plasma and salivary melatonin. The increase in salivary melatonin excretion may have a periodontal protective role.

Assessment of Oral Health in Peritoneal Dialysis Patients with and without Diabetes Mellitus

“…The CPI index is currently recommended by the WHO, and it consists of dividing the oral cavity into sextants, with index teeth in each sextant. The index teeth are 17/16 for the 1st sextant, 11 for the 2nd, 26/27 for the 3rd, 36/37 for the 4th, 31 for the 5th, and 47/46 for the 6th (11,12). The index teeth are then scored as follows: code 0 = healthy periodontium without pathologic changes; code 1 = bleeding on gentle probing; code 2 = calculus deposition; code 3 = probing depth of 4 -5 mm; code 4 = probing depth 6 mm or deeper; code X = 3 or more teeth missing.…”

Antioxidant effects of melatonin in heart tissue after induction of experimental periodontitis in rats

“…Several studies have provided evidence of the positive contributions of melatonin and its physiological and pathological implications in the oral cavity (24)(25)(26)(27). Gülle et al (27) reported that melatonin ameliorated periodontal inflammation-induced organ injuries in rats.…”

Subcellular distribution of melatonin receptors in human parotid glands

“…The free radical scavenging action of melatonin (Cutando et al 2003(Cutando et al , 2007Galano et al 2011), as demonstrated in the oral cavity, appears to be the principal non-receptormediated role of the hormone. Other actions, such as immunomodulatory and protective functions (Cutando et al 2003;Carrillo-Vico et al 2005;Konturek et al 2007), are regulated by its interaction with retinoid orphan receptors/retinoid Z receptors (RZR⁄ROR), a family of nuclear receptors (Cutando et al 2011).…”

“…Other actions, such as immunomodulatory and protective functions (Cutando et al 2003;Carrillo-Vico et al 2005;Konturek et al 2007), are regulated by its interaction with retinoid orphan receptors/retinoid Z receptors (RZR⁄ROR), a family of nuclear receptors (Cutando et al 2011). Most of the biological functions of melatonin are thought to be mediated by the membrane receptors, melatonin 1 (MT1) and 2 (MT2).…”