Physiopathology of prolactin secretion in obesity

Abstract

In many species prolactin is of biological importance and has a major role in determining the deposition and mobilization of fat. In human physiology, outside pregancy, prolactin secretion is altered by increasing body weight in both children and adults. Prolactin in this circumstance appears to be marker of hypothalamic ± pituitary function: the prolactin response to insulin-hypoglycaemia, thyrotrophin releasing hormone stimulation and other stimulatory factors may be diminished. In addition, obesity alters the 24 h spontaneous release of prolactin with a generalised dampening of release. A number of explanations have been given as possible causes for these alterations, but it seems likely that they re¯ect obesity per se and are associated with hyperinsulinaemia. Weight reduction, with accompanying decrease in plasma insulin levels, leads to a normalization of prolactin responses in most, but not all, circumstances. To date, no molecular basis has been identi®ed which links prolactin with increasing body fatness, weight and appetite: new data suggests a possible link in obese men between fasting plasma prolactin and leptin concentrations.

Hyperprolactinemia and body weight: prevalence of obesity and overweight in patients with hyperprolactinemia

“…Weight reduction, with accompanying decrease in insulin levels, has been shown to lead to a normalization of Prl response in most, but not all, circumstances [10]. In a study with obese subjects, no significant association was found between baseline Prl levels and the degree of obesity in these patients [23].…”

“…In humans, outside pregnancy, Prl secretion is altered by increasing body weight in adults and children. However, no molecular basis has been found which links Prl with increasing body fat, weight and appetite, although some data suggest the involvement of Prl with leptin [10].…”

Increased Lipid Levels Improves after Treatment with Cabergolin in Patients with Prolactinoma

“…No correlation was observed between prolactin and BMI in our study; as previously mentioned study. It is suggested that obesity is occurs secondary to the changing in hypothalamic energy metabolism [13]. But, direct relationship between high prolactin and BMI is not clear [14].…”

Medical Assessment and Preparation of Patients Undergoing Bariatric Surgery

“…When prolactin levels fall after treatment so does patients' weight (Greenman, Tordjman et al 1998). The relationship between prolactin level and weight could be due to the changes within central dopaminergic pathway and reduction in serotonin secretion (Kopelman 2000). Prolactin level has been found to be elevated in obese females (Kok, Roelfsema et al 2004) and levels falls after weight loss (Kok, Roelfsema et al 2006).…”

“…Prolactin level has been found to be elevated in obese females (Kok, Roelfsema et al 2004) and levels falls after weight loss (Kok, Roelfsema et al 2006). Raised prolactin level in obesity might be a result of hyperinsulinaemic state or alterations in doperminergic and serotoninergic activities centrally (Kopelman 2000). …”