Alleviation of Oxidative Stress in Dental Pulp Cells Following 4-Hexylresorcinol Administration in a Rat Model

4-Hexylresorcinol: pharmacologic chaperone and its application for wound healing

4-Hexylresorcinol (4HR) is amphiphilic organic chemical and auto-regulator for micro-organism. As 4HR administration induces the stress on the endoplasmic reticulum, 4HR changes protein folding. The application of 4HR inhibits NF-κB signal pathway and TNF-α production. In addition, 4HR administration increases VEGF, TGF-β1, and calcification associated proteins. As a consequence, 4HR administration increases angiogenesis and bone formation in wounded area. Strong anti-inflammatory reaction and capillary regeneration in diabetic model demonstrate that 4HR can be applied on many types of surgical wound.

The effect of 4-hexylresorinol administration on NAD+ level and SIRT activity in Saos-2 cells

Background

4-hexylresorcinol (4HR) has been shown to have anti-oxidant activity similar to that of resveratrol. As resveratrol increases sirtuin (SIRT) activity, 4HR might behave similarly to resveratrol.

Method

In this study, the expression levels of SIRT1, SIRT3, and SIRT6 were evaluated after 4HR administration (1–100 μM). As NAD+ is a substrate for SIRTs, its levels with SIRT activity were also studied.

Results

In the results, SIRT3 (100 μM at 24 h) and SIRT6 (1–100 μM at 24 h and 10 μM at 8 h) were shown to have significantly higher expression levels compared to untreated control (p < 0.05). Pan-SIRT activity and the NAD+ level was significantly increased compared to that of the untreated control (p < 0.05; 10 and 100 μM at 24 h).

Conclusion

4HR administration increased SIRT activity and the NAD+ level in Saos-2 cells.

Histological Aspects Regarding Dental Pulp of Diabetic Patients

Background: The possible histological changes in dental pulp in teeth of diabetic patients are important to be understood, as the clinician will consider the best treatment choice for those teeth, especially if they are affected by decay. The aim of this paper is to assess if there are effects of diabetes-associated hyperglycemia on the nervous and vascular system of the dental pulp. Methods: Twenty-three dental pulp specimens of patients aged 36–70 years old were analyzed. All patients had been diagnosed with type 2 diabetes for at least 5 years. Results: Most of the patients had poorly controlled hyperglycemia, deep caries, but no clinical signs of pulpitis. The histological aspects of pulp specimens included frequently seen inflammatory infiltrate, degeneration of the nerves, thickened blood vessel walls, pulp sclerosis and frequent pulp calcifications, and even small necrotic areas. Conclusion: The analyzed dental pulp specimens of carious teeth of type 2 diabetic patients show fibrotic transformation of the dental pulp, with the presence of calcifications, arteriosclerosis and inflammatory infiltrate. In this situation, the attitude of the dentist in pulp vitality preservation in the case of carious teeth of diabetic patients should be limited.