title: Influence of GABA and GABA-producing Lactobacillus brevis DPC 6108 on the development of diabetes in a streptozotocin rat model.
abstract: The aim of this study was to investigate if dietary administration of γ-aminobutyric acid (GABA)-producing Lactobacillus brevis DPC 6108 and pure GABA exert protective effects against the development of diabetes in streptozotocin (STZ)-induced diabetic Sprague Dawley rats. In a first experiment, healthy rats were divided in 3 groups (n=10/group) receiving placebo, 2.6 mg/kg body weight (bw) pure GABA or L. brevis DPC 6108 (~10(9)microorganisms). In a second experiment, rats (n=15/group) were randomised to five groups and four of these received an injection of STZ to induce type 1 diabetes. Diabetic and non-diabetic controls received placebo [4% (w/v) yeast extract in dH2O], while the other three diabetic groups received one of the following dietary supplements: 2.6 mg/kg bw GABA (low GABA), 200 mg/kg bw GABA (high GABA) or ~10(9) L. brevis DPC 6108. L. brevis DPC 6108 supplementation was associated with increased serum insulin levels (P<0.05), but did not alter other metabolic markers in healthy rats. Diabetes induced by STZ injection decreased body weight (P<0.05), increased intestinal length (P<0.05) and stimulated water and food intake. Insulin was decreased (P<0.05), whereas glucose was increased (P<0.001) in all diabetic groups, compared with non-diabetic controls. A decrease (P<0.01) in glucose levels was observed in diabetic rats receiving L. brevis DPC 6108, compared with diabetic-controls. Both the composition and diversity of the intestinal microbiota were affected by diabetes. Microbial diversity in diabetic rats supplemented with low GABA was not reduced (P>0.05), compared with non-diabetic controls while all other diabetic groups displayed reduced diversity (P<0.05). L. brevis DPC 6108 attenuated hyperglycaemia induced by diabetes but additional studies are needed to understand the mechanisms involved in this reduction.
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.|3 School of Microbiology, University College Cork, Cork, Ireland.
authors.forename: T M
authors.initials: TM
authors.lastname: Marques
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.|3 School of Microbiology, University College Cork, Cork, Ireland.
authors.forename: E
authors.initials: E
authors.lastname: Patterson
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: R
authors.initials: R
authors.lastname: Wall
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: O
authors.initials: O
authors.lastname: O'Sullivan
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|3 School of Microbiology, University College Cork, Cork, Ireland.
authors.forename: G F
authors.initials: GF
authors.lastname: Fitzgerald
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: P D
authors.initials: PD
authors.lastname: Cotter
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|4 Department of Psychiatry and Neurobehavioural Science, Biosciences Institute, University College Cork, Cork, Ireland.
authors.forename: T G
authors.initials: TG
authors.lastname: Dinan
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.
authors.forename: J F
authors.initials: JF
authors.lastname: Cryan
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.
authors.forename: R P
authors.initials: RP
authors.lastname: Ross
authors.affiliation: 1 APC Microbiome Institute, University College Cork, Cork, Ireland.|2 Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
authors.forename: C
authors.initials: C
authors.lastname: Stanton
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic; D003921:Diabetes Mellitus, Experimental / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000378:metabolism; D052196:Levilactobacillus brevis / Q000378:metabolism; D010919:Placebos / Q000008:administration & dosage; D019936:Probiotics / Q000008:administration & dosage*; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage* / Q000378:metabolism*
chemical_list: D000903:Antibiotics, Antineoplastic; D007004:Hypoglycemic Agents; D010919:Placebos; D005680:gamma-Aminobutyric Acid
keywords: probiotic; streptozotocin; type-1 diabetes; γ-aminobutyric acid