Melatonin controls cell proliferation and modulates mitochondrial physiology in pancreatic stellate cells.

We have investigated the effects of melatonin on major pathways related with cellular proliferation and energetic metabolism in pancreatic stellate cells. In the presence of melatonin (1 mM, 100 µM, 10 µM, or 1 µM), decreases in the phosphorylation of c-Jun N-terminal kinase and of p44/42 and an increase in the phosphorylation of p38 were observed. Cell viability dropped in the presence of melatonin. A rise in the phosphorylation of AMP-activated protein kinase was detected in the presence of 1 mM and 100 µM melatonin. Treatment with 1 mM melatonin decreased the phosphorylation of protein kinase B, whereas 100 µM and 10 µM melatonin increased its phosphorylation. An increase in the generation of mitochondrial reactive oxygen species and a decrease of mitochondrial membrane potential were noted following melatonin treatment. Basal and maximal respiration, ATP production by oxidative phosphorylation, spare capacity, and proton leak dropped in the presence of melatonin. The expression of complex I of the mitochondrial respiratory chain was augmented in the presence of melatonin. Conversely, in the presence of 1 mM melatonin, decreases in the expression of mitofusins 1 and 2 were detected. The glycolysis and the glycolytic capacity were diminished in cells treated with 1 mM or 100 µM melatonin. Increases in the expression of phosphofructokinase-1 and lactate dehydrogenase were noted in cells incubated with 100 µM, 10 µM, or 1 µM melatonin. The expression of glucose transporter 1 was increased in cells incubated with 10 µM or 1 µM melatonin. Conversely, 1 mM melatonin decreased the expression of all three proteins. Our results suggest that melatonin, at pharmacological concentrations, might modulate mitochondrial physiology and energy metabolism in addition to major pathways involved in pancreatic stellate cell proliferation.

Lupus eritematoso sistémico ampolloso en un paciente varón de 16 años / Bullous systemic lupus erythematosus in a 16-year-old male patient

RESUMEN El lupus eritematoso sistémico ampolloso (LESA) es una enfermedad vesículo-ampollosa mediada por autoanticuerpos en pacientes con lupus eritematoso sistémico (LES). Se observan vesículas y ampollas tensas sobre una piel edematosa, eritematosa y, en ocasiones, normal en cualquier región del cuerpo, incluyendo áreas mucosas y que no han sido fotoexpuestas. Se presenta el caso de un paciente varón de 16 años de edad con nefritis lúpica, que al séptimo día de hospitalización presenta múltiples ampollas serosas y hemorrágicas sobre el rostro, el tronco, el abdomen y las extremidades superiores. El estudio histológico mostró una dermatosis ampollar subepidérmica con numerosos neutrófilos.

ABSTRACT Bullous systemic lupus erythematosus (BSLE) is a vesiculobullous disease mediated by autoantibodies in patients with systemic lupus erythematosus (SLE). Tense vesicles and bullae are seen on an edematous, erythematous and sometimes normal skin in any body region, including mucous membranes and non-photoexposed areas. This is the case of a 16-year-old male patient with lupus nephritis who, on the seventh day of hospitalization, presented multiple serous and hemorrhagic blisters on the face, trunk, abdomen and upper extremities. The histological study showed a subepidermal bullous dermatosis with numerous neutrophils.