Investigation of the effects of centrally injected nesfatin-1 on the hypothalamic cyclooxygenase and lipoxygenase enzymes using western blotting

Nesfatin-1 is an anorexigenic neuropeptide influencing various metabolic actions in the regulation of body temperature, energy homeostasis, gastrointestinal system, glucose homeostasis, stress and reproduction. Both central and peripheral Nesfatin-1 administration have been found to alter blood pressure, heart rate and plasma catecholamine and vasopressin concentrations. The involvement of oxytocin, melanocortin and pro-opiomelanocortin receptors in Nesfatin-1's cardiovascular effects has previously been demonstrated. Apart from these mechanisms, limited knowledge is available on the central mode of cardiovascular effects of Nesfatin-1. The mediation of Nesfatin-1-evoked cardiovascular effects is similar to arachidonic acid's mode of action in exerting these effects. Arachidonic acid is a precursor molecule in the synthesis of prostaglandins and leukotrienes mediated by cyclooxygenase and lipoxygenase enzymes. Inhibiting these enzymes has been shown to suppress Nesfatin-1's anti-inflammatory effects. This study was designed to investigate the expression of cyclooxygenase (COX1 and COX2) and lipoxygenase (LOX) enzymes upon central Nesfatin-1 administration. 21 male Sprague-Dawley rats distributed among control, saline and nesfatin groups were used as test subjects. While control subjects were sacrificed without any pharmacological procedure, saline and nesfatin groups were sacrificed after 20 minutes of saline or Nesfatin-1 administration respectively. The hypothalamus was isolated and samples were tested with Western Blotting to determine the immunoreaction of cyclooxygenase and lipoxygenase enzymes. A pooled study was also performed. While Western Blotting results of individual-samples study did not show significant rise in the concentration of these enzymes, the pooled study showed a slight rise in their concentrations.