Leptin concentrations in response to acute stress predict subsequent intake of comfort foods

Both animals and humans show a tendency toward eating more “comfort food” (high fat, sweet food) after acute stress. Such stress eating may be contributing to the obesity epidemic, and it is important to understand the underlying psychobiological mechanisms. Prior investigations have studied what makes individuals eat more after stress; this study investigates what might make individuals eat less. Leptin has been shown to increase following a laboratory stressor, and is known to affect eating behavior. This study examined whether leptin reactivity accounts for individual differences in stress eating. To test this, we exposed forty women to standardized acute psychological laboratory stress (Trier Social Stress Test) while blood was sampled repeatedly for measurements of plasma leptin. We then measured food intake after the stressor in 29 of these women. Increasing leptin during the stressor predicted lower intake of comfort food. These initial findings suggest that acute changes in leptin may be one of the factors modulating down the consumption of comfort food following stress

Pairs of cyclic AMP analogs that are specifically synergistic for type I and type II CAMP dependent protein kinases mimic thyrotropin effects on the function, differentiation, expression and mitogenesis of dog thyroid cells

The role of the two different isozymes of the cAMP‐dependent protein kinase is still unclear. We have investigated the potential roles for each isozyme in dog thyroid cells, a model in which the function, expression of differentiation and proliferation are positively regulated by thyrotropin acting through cyclic AMP. The dog thyroid contains both type I and type II cAMP‐dependent protein kinases. These isozymes were selectively activated in vitro by type‐I‐directed and type‐II‐directed analog pairs. In thyroid slices, both type‐I directed and type II‐directed analog pairs synergistically activated thyroid hormone synthesis, as measured by incorporation of 131I into proteins and thyroid hormone secretion as determined by the release of butanol‐extractable 131I. In primary cultures of dog thyroid cells both isozyme‐directed analog pairs synergistically enhanced iodide trapping, a marker of differentiation, and DNA synthesis, as measured by the percentage of cells incorporating [3H]thymidine into their nuclei. However, DNA synthesis was more sensitive to type‐I‐directed pairs. The results demonstrate that both cAMP‐dependent protein kinase isozymes can mediate the action of cAMP on function, differentiation expression and cell proliferation in dog thyroid cells.info:eu-repo/semantics/publishe