Effects of Supplementation With Probiotics on Long-Term Potentiation Impairment in Diabetic Rats



Davari S¹ ; Talaei SA² ; Salami M² ; Fazeli MR³ ; Alaei H⁴ Show Affiliations
Source: Journal of Isfahan Medical School Published:2013

Abstract

Background: Increased oxidative stress load in diabetes mellitus can damage learning and memory. Since probiotics have been suggested to reduce this load, this study investigated the effects of probiotics on induction of long-term potentiation (LTP) in neurons of hippocampal cornu ammonis 1 (CA1) area of diabetic rats. Methods: This experimental study was carried out on 40 male Wistar rats in four randomly allocated groups of 10. The groups were named as control (CO), control-probiotic (CP), control-diabetic (CD), and diabetic-probiotic (DP). Probiotic supplements included Lactobacillus acidophilus, Lactobacillus fermentum, Bifidobacterium lactis (334 mg of each with colony-forming units ~ 1010). The supplement was solved in drinking water each 12 hours and used for eight weeks. Stimulating hippocampal Schaffer collaterals, field excitatory postsynaptic potentials (fEPSP) of neurons of CA1 area were recorded for 30 minutes. Then, high frequency stimulation was performed and fEPSPs were recorded for 120 minutes. Findings: Comparing to the control animals, induction of diabetes caused decreases in the basic responses of neurons (P < 0.001). On the other hand, supplementation with probiotics could restore the responses. Moreover, diabetes prevented LTP induction in CA1 area neurons and probiotics opposed it. DP animals showed conspicuous increases in weight (P = 0.031) and serum insulin (P < 0.001) and a reduction in blood sugar (P = 0.006). Conclusion: Probiotics supplement improves impairment of LTP induction in diabetic rats' hippocampus via increase in insulin secretion, decrease in blood sugar, and may be rise of antioxidant capacity.