Immunoregulatory effects of isotretinoin in patients with acne.

BACKGROUND: In vitro studies have shown that retinoids influence T-cell differentiation. OBJECTIVES: To study the effect of isotretinoin on T-cell differentiation markers in patients with acne. METHODS: A total of 37 patients with acne vulgaris (25 female, 12 male, age 19.6 ± 3.7 years) and 30 age- and sex-matched healthy controls (19 female, 11 male, age 20.5 ± 4.4 years) were included in the study. Screening for biochemical parameters in serum samples were done just before initiation (pretreatment) and after 3 months of isotretinoin treatment (post-treatment) in the acne group. RESULTS: Baseline levels of tumour necrosis factor (TNF)-α (P<0.0001), interleukin (IL)-4 (P<0.0001), IL-17 (P<0.0001) and interferon (IFN)-γ (P=0.002) were significantly higher in the acne group compared with the control group. TNF-α (P<0.0001), IL-4 (P<0.0001), IL-17 (P<0.0001) and IFN-γ (P<0.0001) levels decreased after isotretinoin treatment. TNF-α and IL-4 values after isotretinoin treatment were similar to those of the control group. However, levels of IL-17 (P<0.0001) after isotretinoin treatment were higher than those of the control group, despite a significant decline after treatment. Levels of IFN-γ (P<0.0001) after isotretinoin treatment were lower than those of the control group. CONCLUSIONS: This study shows that isotretinoin treatment significantly decreases TNF, IL-4, IL-17 and IFN-γ levels in patients with acne. We failed to show that isotretinoin redirects naive T helper (Th) differentiation preferentially towards the Th2 cell lineage.

Serum holotranscobalamine, vitamin B12, folic acid and homocysteine levels in patients with vitiligo.

Few studies have investigated the role of vitamin B12 metabolism in vitiligo. We tested the hypothesis that vitamin B12 and folate metabolism might have an influence on the pathogenesis of vitiligo. Full blood count and levels of folic acid, vitamin B12, homocysteine and holotranscobalamine were examined for 69 patients with vitiligo and 52 controls. The vitiligo group had higher levels of homocysteine (P < 0.01) and haemoglobin (P < 0.01) levels, and lower levels of vitamin B12 (P < 0.01) and holotranscobalamine (P < 0.0001) than the control group. Folic acid levels were similar for both groups. In a risk analysis, hyperhomocysteinaemia (≥ 15 µmol/L, P < 0.01) and vitamin B12 deficiency (< 200 pg/mL, P < 0.01) were significant risk factors for vitiligo. Patients with holotranscobalamine levels in the lowest quartile had an increased risk for co-occurrence of vitiligo (P < 0.005). Vitamin B12 deficiency and hyperhomocysteinaemia may share a common genetic background with vitiligo.

Relationship between hair cadmium levels, indoor ETS exposure and wheezing frequency in children.

BACKGROUND: Cadmium (Cd) is a toxic heavy metal and the components of tobacco and scalp hair effectively reflect a long-term environmental exposure. OBJECTIVE: The aim of this study was to assess the concentration of Cd levels in the hair of children with recurrent wheezing, and to evaluate the predictors of elevated Cd levels with a focus on anthropometric, environmental, and dietary factors. METHODS: In this case-control study, scalp hair was obtained from 65 children with recurrent wheezing (RW) and from 65 healthy children (HC). Hair Cd concentrations were determined by ICP-MS. RESULTS: Median (IQR) hair Cd levels were 0.22 µg/kg (0.10-0.35) in RW group and 0.12 µg/kg (0.04-0.23) in HC group (p = 0.013). Multivariable logistic regression model results showed that being a child with RW (OR = 6.28; p = 0.001), ETS exposure at home (OR=22.56; p < 0.001), and mother's education level (OR = 0.49; p = 0.020), are the major predictor variables for elevated hair Cd levels (cut off >0.17 µg/kg). In RW group, multivariable logistic regression results showed that hair Cd levels of >0.17 µg/kg was significantly predictive of having three or more wheezing episodes in RW group after adjustment for ETS exposure at home (OR = 5.48; p = 0.012). CONCLUSION: We demonstrated that the more children are exposed to ETS at home, the more they are exposed to heavy metals like Cd. Especially children who have had three or more wheezing attacks over the last six months are much more susceptible than the other asthmatic and non-asthmatic children, and Cd exposure aggravates their asthmatic status.

Isotretinoin does not induce insulin resistance in patients with acne.

BACKGROUND: Isotretinoin treatment causes hypertriglyceridaemia. Insulin resistance is also associated with hypertriglyceridaemia. It is not known if isotretinoin is related to insulin resistance. AIM: To test this hypothesis, we measured insulin resistance in 48 patients with acne vulgaris (AV) before and after 3 months of isotretinoin treatment. METHODS: In total, 48 patients with AV who attended the dermatology outpatient clinic at Kecioren Research and Training Hospital were included. Screening for biochemical parameters was performed just before the start of treatment (pretreatment) and after 4 months of isotretinoin therapy (post-treatment). The parameters measured were insulin, C peptide, fasting blood glucose, aspartate and alanine aminotransferases (AST, ALT), total cholesterol (TC), triglyceride, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein (LDL-C) and very low-density lipoprotein cholesterol. Insulin resistance was measured using the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) method. RESULTS: Compared with initial values, AST, ALT, TC, LDL-C and triglyceride levels were significantly increased (P < 0.01, < 0.05, < 0.01, < 0.05 and < 0.01, respectively), but there was no significant change in fasting blood glucose, insulin, C-peptide levels or HOMA-IR. CONCLUSIONS: Three months of isotretinoin treatment did not change insulin sensitivity in patients with AV. Further studies with insulin resistance models may even reveal an improvement in insulin resistance, as experimental animal studies have previously shown.

Short-term isotretinoin treatment decreases insulin-like growth factor-1 and insulin-like growth factor binding protein-3 levels: does isotretinoin affect growth hormone physiology?

BACKGROUND: Isotretinoin is an effective treatment for acne vulgaris. However, it has numerous side-effects. It was previously reported that serum growth hormone (GH) levels decreased with isotretinoin treatment. OBJECTIVES: To analyse whether isotretinoin has any effects on insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP3) and GH levels. METHODS: Forty-seven patients aged 21.5 +/- 5.1 years (mean +/- SD) with acne vulgaris were included in this study. Isotretinoin therapy was initiated at a dose of 0.5-0.75 mg kg(-1) daily and then adjusted to 0.88 mg kg(-1) daily as maintenance dosage after 1 month. Screening for biochemical and hormonal parameters was performed just before initiation and after 3 months of isotretinoin treatment. RESULTS: IGF-1 and IGFBP3 levels decreased significantly after treatment (P < 0.01), while GH levels did not change. Post-treatment, significant increases were seen in aspartate aminotransferase, total cholesterol, low-density lipoprotein cholesterol, triglycerides and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (P < 0.0001) while high-density lipoprotein cholesterol levels were significantly decreased (P < 0.0001). CONCLUSIONS: Isotretinoin therapy may have an effect on GH physiology, and further studies are needed to understand this association.