Body mass index, selected dietary factors, and acne severity: are they related to in situ expression of insulin-like growth factor-1?

Objective: To evaluate the possible role of insulin-like growth factor (IGF)-1 in acne vulgaris (AV) pathogenesis through its immunohistochemical localization in acne skin biopsies and to investigate the relationship of its expression with body mass index (BMI), selected dietary factors, and acne severity.

Study design: Using the standard immunohistochemical techniques, we examined 60 acne cases and 40 gender- and age-matched, healthy subjects, representing the control group.

Results: IGF-1 was overexpressed in AV lesions as compared to in normal skin, both in epidermis and pilo-sebaceous units (p < 0.0001 for both). There was significant association between strong intensity of IGF-1 and high BMI values (≥ 30) in AV cases as compared to controls, with high (≥ 30) and low (< 30) BMI values, both in epidermis (p < 0.0001 for both) and pilosebaceous units (p <0.0001 for both). Strong IGF-1 intensity was significantly associated with higher mean values of BMI (p = 0.01) and severe AV (p = 0.04). Significant associations between high BMI values and acne severity (p = 0.001) and acne aggravation by dairy products intake (p = 0.03) were demonstrated.

Conclusion: IGF-1 may play a role in AV pathogenesis through its role in keratinocyte proliferation, sebaceous lipogenesis, and androgen synthesis. The significant association between strong IGF-1, high BMI, and severe acne underscores the value of dietary intervention in the management of AV.