Abstract
Background: Preliminary studies revealed that 4-aminobutyric acid (GABA) is a key and major inhibitory neurotransmitter in the brain. Evidence from many animal studies and even some clinical studies indicate that GABA is responsible for regulating behavior and also plays an important role in brain functions. Previous studies presented Glutamic acid decarboxylase as a catalyst for the conversion of glutamic acid to GABA.
Objectives: The aim of this study was to evaluate the effects of saffron on GABA content in the hypothalamus of rats.
Materials and Methods: Male rats weighing 190 - 210 g were used. They were maintained in a temperature-controlled room with a 12-hour light/dark illumination cycle. The rats were fed standard pellet feed and had access to water ad libitum. The animals were divided into three groups: The first group received a 250 L intraperitoneal injection of 0.05 g/mL saffron (Group I). The second group received a 250 L intraperitoneal injection of 0.1 g/mL saffron (Group II). The third group acted as the control and received only water (Group III). The time intervals chosen for this experiment were 1, 2, 4, and 8 weeks following the administration of saffron.
At least six animals were assigned to each experimental group. At each time interval, the animals were anaesthetized and brain tissue extracted, hypothalami separated and homogenized in PBS solution, rinsed with PBS, re-filtered, and centrifuged at 1200 g for 10 minutes.
Results: In this study, both doses of saffron (0.05g/mL[Group I];and0.1g/mL[Group II]) caused significantly increasedGABAcontent in each hypothalamus. GABA in Group I increased significantly compared to the control group (1.00 0.05 [mean SD, n = 8] vs. 0.29 0.05, mM). GABA in Group II also increased significantly compared to the control group (1.45 0.07 [mean SD, n = 8] vs. 0.290.05, mM). The effect of saffron on GABA was also dose dependent; the only exception occurring during the final time interval for the 0.1 g/mL saffron concentration.
Conclusions: The results of this study demonstrated a significant increase in hypothalamus GABA content from saffron administration. One explanation for this observation could be the stimulation of glutamic acid decarboxylase the primary enzymeresponsible for the production of GABA. Saffron may be a potential therapeutic agent for improving neurotransmitter levels.