Ultraviolet B (UVB) induces development of early melanocytic progenitors via increased oxidative stress in vitro suggesting the use of antioxidants after repigmentation [corrected] in UVB phototherapy for vitiligo

Thiol/disulfide homeostasis and its relationship with insulin resistance in patients with rosacea

BACKGROUND

Rosacea is a chronic inflammatory cutaneous disease that can be associated with cardiometabolic disorders. Oxidative stress is included in the pathogenesis of rosacea, and thiol-disulfide homeostasis (TDH) acts as antioxidants.

OBJECTIVE

To evaluate the TDH and metabolic parameters in patients with rosacea.

MATERIAL AND METHODS

A total of 42 rosacea patients and 50 controls participated in this prospective study. Demographic data, clinical entities, anthropometric measurements, and laboratory findings were recorded. Additionally, TDH was measured by an automated spectrophotometric method.

RESULTS

Rosacea patients had greater body mass index values (27.9 ± 5.2 kg/m² vs. 23 ± 1.4 kg/m², p < 0.001), waist-hip ratios (0.87 ± 0.1 vs. 0.77 ± 0.8, p < 0.001), and insulin resistance (3.0 ± 2.0 vs. 1.3 ± 0.5, p < 0.001) compared with controls. Disulfide levels, the disulfide/native thiol ratio (DNTR), and the disulfide/total thiol ratio (DTTR) were increased (p < 0.05) in rosacea patients. Native thiol and total thiol levels and the native/total thiol ratio (NTTR) were decreased in rosacea patients (p < 0.05). Different rosacea subtypes had no effect on oxidative stress markers. The duration of illness and insulin resistance values significantly correlated with DNTR and DTTR in the rosacea group (p < 0.05).

CONCLUSION

Rosacea has a metabolic milieu with increased oxidative stress and insulin resistance.

The necessity of antinuclear antibody investigation in pre-phototherapy vitiligo patients: A retrospective study

BACKGROUND

Narrowband UVB (NBUVB) phototherapy is the cornerstone treatment for vitiligo. Before its initiation, some experts recommend antinuclear antibody (ANA) screening out of concern for either photosensitivity to NBUVB or autoimmune disease exacerbation during treatment. As vitiligo is considered an autoimmune disorder, ANAs can be positively found in the disease without any clinical importance. The necessity for ANA investigations for pre-phototherapy vitiligo patients is therefore questioned.

METHODS

We conducted a retrospective study to investigate vitiligo patients who had been checked for ANA before commencing NBUVB phototherapy. Demographic data-including vitiligo type and age of onset-were collected. Samples of ANA, anti-thyroglobulin, and anti-thyroid peroxidase were obtained. The phototherapy treatment protocol and cutaneous reactions to the phototherapy were also recorded.

RESULTS

Among 85 Thai vitiligo patients, the ANA prevalence was 35.3%. The speckled ANA pattern was the most common, and the large majority of patients (80%) had a titer of ≤1:100. Factors associated with positive ANA were female gender and positive anti-thyroglobulin. There were no statistical differences between the phototoxic reactions or phototoxic doses of NBUVB of the ANA-positive vitiligo and ANA-negative vitiligo groups. No cases of SLE were detected in ANA-positive group.

CONCLUSIONS

ANA positivity was not correlated with the incidence or dose of phototoxic reaction in phototherapy treated vitiligo, and it may not a predictive factor for SLE diagnosis in vitiligo. ANA might therefore not need to be routinely checked in pre-phototherapy in vitiligo, unless there are clinical suspicions of an autoimmune disease. However, ANA might be involved in part of the cutaneous photoadaptation response to phototherapy.