leptin and Skin-Diseases

Leptin is an adipokine, adipocyte-derived compound, which acts both as a hormone and cytokine. It is mainly synthesized by adipocytes of white adipose tissue. Leptin possesses pleiotropic functions including, among others, stimulation of angiogenesis and production of proinflammatory cytokines. The various types of leptin activity are related to the wide distribution of leptin receptors. This adipokine acts by activating intracellular signaling cascades such as JAKs (Janus kinases), STATs (signal transducers and activators of transcription), and others.In a course of obesity, an increased serum level of leptin coexists with tissue receptor resistance. It has been reported that enhanced leptin levels, leptin receptor impairment, and dysfunction of leptin signaling can influence skin and hair. The previous studies revealed the role of leptin in wound healing, hair cycle, and pathogenesis of skin diseases like psoriasis, lupus erythematosus, and skin cancers. However, the exact mechanism of leptin's impact on the skin is still under investigation. Herein, we present the current knowledge concerning the role of leptin in psoriasis and selected skin diseases.

Topics: Adipocytes; Adipokines; Adipose Tissue; Animals; Humans; Janus Kinases; Leptin; Lupus Erythematosus, Cutaneous; Psoriasis; Receptors, Leptin; Signal Transduction; Skin Diseases; Skin Neoplasms; STAT Transcription Factors

It is an indisputable fact that obesity is associated with a series of health problems. One important hallmark of obesity is excessive accumulation of lipids in the adipocyte, especially triglyceride (TG). Currently, the adipocyte has been considered not only as a huge repository of excess energy in the form of fat but also as an important source of multiple hormones and cytokines called adipokines. In obesity, the adipocyte is dysfunctional with excessive production and secretion of pro-inflammatory adipokines, such as tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and leptin. On the other hand, accumulating evidence has shown that leptin plays a vital role in stimulating angiogenesis, controlling lipid metabolism, and modulating the production of pro-inflammatory cytokines. Furthermore, the various activities of leptin are related to the wide distribution of leptin receptors. Notably, it has been reported that enhanced leptin levels and dysfunction of the leptin signaling pathway can influence diverse skin diseases. Recently, several studies revealed the roles of leptin in wound healing, the hair cycle, and the pathogenic development of skin diseases, such as psoriasis, lupus erythematosus, and dermatological cancers. However, the exact mechanisms of leptin in modulating the dermatological diseases are still under investigation. Therefore, in the present review, we summarized the regulatory roles of leptin in the pathological progression of diverse diseases of skin and skin appendages. Furthermore, we also provided evidence to elucidate the complicated relationship between leptin and different dermatological diseases, such as systemic lupus erythematosus (SLE), psoriasis, hidradenitis suppurativa, and some skin tumors.

Topics: Animals; Biomarkers; Disease Susceptibility; Energy Metabolism; Gene Expression Regulation; Hair; Hair Diseases; Humans; Leptin; Obesity; Organ Specificity; Reactive Oxygen Species; Skin Diseases

This review focuses on recent publications concerning medical complications in patients with eating disorders, including anorexia nervosa and bulimia nervosa.. Recent literature continues to reflect that multiple organ systems are frequently affected by eating disorders. The literature underscores the frequently cited risk of premature death in those with anorexia nervosa. A plethora of dermatologic changes have been described, some signaling serious underlying pathophysiology, such as purpura, which indicates a bleeding diathesis. Much of the literature continues to delineate the fact that diabetic patients with eating disorders are at high risk of developing diabetic complications. Gastrointestinal complications can be serious, including gastric dilatation and severe liver dysfunction. Acrocyanosis is common, and patients with anorexia nervosa are at risk of various arrhythmias. Low-weight patients are at high risk for osteopenia/osteoporosis. Nutritional abnormalities are also common, including sodium depletion and hypovolemia, hypophosphatemia and hypomagnesemia. Resting energy expenditure, although very low in low-weight patients, increases dramatically early in refeeding.. Medical complications are common and often serious in patients with eating disorders, particularly those with anorexia nervosa.

Topics: Anorexia Nervosa; Bone Diseases; Bulimia Nervosa; Cardiovascular Diseases; Endocrine System Diseases; Gastrointestinal Diseases; Humans; Leptin; Lung Diseases; Nutrition Disorders; Skin Diseases

Leptin, an adipocyte-derived hormone, has been shown to have several immunological effects similar to those of proinflammatory cytokines. The relationship between serum leptin, psoriasis, and obesity is still conflicted, and very few studies have investigated its role in skin diseases other than psoriasis.. To evaluate the possible relationship between serum leptin in nonobese patients with psoriasis and other randomly selected skin diseases.. Eighty subjects (40 patients with psoriasis, 20 patients with other randomly selected skin diseases, and 20 healthy controls) were included in the study. Fasting serum leptin levels of the study groups were examined by sandwich enzyme-linked immunosorbent assay.. Elevated serum leptin levels were detected in both nonobese patients with psoriasis (P=.004) and those with other randomly selected skin diseases (P=.05). Leptin levels failed to correlate to the Psoriasis Area and Severity Index score of psoriatic patients. Both sexes demonstrated comparable levels of serum leptin in psoriatic patients, while female patients suffering from other skin diseases showed higher levels of serum leptin than did males of the same group.. Leptin may play a role in the immunopathogenesis of psoriasis and other skin diseases, even in the absence of obesity as a cofactor.

Topics: Adult; Aged; Body Mass Index; Body Weight; Enzyme-Linked Immunosorbent Assay; Female; Humans; Leptin; Male; Middle Aged; Obesity; Psoriasis; Severity of Illness Index; Skin; Skin Diseases; Young Adult

Progression of breast cancer involves cross-talk between epithelial and stromal cells. This cross-talk is mediated by growth factors and cytokines secreted by both cancer and stromal cells. We previously reported expression of interleukin (IL)-1 alpha in a subset of breast cancers and demonstrated that IL-1 alpha is an autocrine and paracrine inducer of prometastatic genes in in vitro systems. To understand the role of IL-1 alpha in breast cancer progression in vivo, we studied the growth of MCF-7 breast cancer cells overexpressing a secreted form of IL-1 alpha (MCF-7IL-1 alpha) in nude mice. MCF-7IL-1 alpha cells formed rapidly growing estrogen-dependent tumors compared to parental cells. Interestingly, IL-1 alpha expression alone was not sufficient for metastasis in vivo although in vitro studies showed induction of several prometastatic genes and matrix metalloproteinase activity in response to cross-talk between IL-1 alpha-expressing cancer cells and fibroblasts. Animals implanted with MCF-7IL-1 alpha cells were cachetic, which correlated with increased leptin serum levels but not other known cachexia-inducing cytokines such as IL-6, tumor necrosis factor, or interferon gamma. Serum triglycerides, but not blood glucose were lower in animals with MCF-7IL-1 alpha cell-derived tumors compared to animals with control cell-derived tumors. Cachexia was associated with atrophy of epidermal and adnexal structures of skin; a similar phenotype is reported in triglyceride-deficient mice and in ob/ob mice injected with leptin. Mouse leptin-specific transcripts could be detected only in MCF-7IL-1 alpha cell-derived tumors, which suggests that IL-1 alpha increases leptin expression in stromal cells recruited into the tumor microenvironment. Despite increased serum leptin levels, animals with MCF-7IL-1 alpha cell-derived tumors were not anorexic suggesting only peripheral action of tumor-derived leptin, which principally targets lipid metabolism. Taken together, these results suggest that cancer cell-derived cytokines, such as IL-1 alpha, induce cachexia by affecting leptin-dependent metabolic pathways.

Topics: Animals; Cachexia; Cell Division; Cell Line, Tumor; Female; Fibroblasts; Humans; Interleukin-1; Leptin; Mammary Neoplasms, Experimental; Mice; Mice, Nude; Neoplasm Transplantation; Peptides; RNA, Messenger; Severity of Illness Index; Skin Diseases; Transplantation, Heterologous; Weight Loss