title: Hyperpalatable Diet and Physical Exercise Modulate the Expression of the Glial Monocarboxylate Transporters MCT1 and 4.
abstract: Hyperpalatable diets (HP) impair brain metabolism, and regular physical exercise has an apparent opposite effect. Here, we combined a prior long-term exposure to HP diet followed by physical exercise and evaluated the impact on some neuroenergetic components and on cognitive performance. We assessed the extracellular lactate concentration, expression of monocarboxylate transporters (MCTs), pyruvate dehydrogenase (PDH), and mitochondrial function in the hippocampus. Male C57BL/6J mice were fed 4 months with HP or a control diet. Subsequently, they were divided in the following groups: control diet sedentary (CDS), control diet exercise (CDE), HP diet sedentary (HPS), and HP diet exercise (HPE) (n = 15 per group) and were engaged for an additional 30-day period of voluntary exercise and HP diet. Relative to the control situation, exercise increased MCT1, MCT4, and PDH protein levels, while the HP diet increased MCT1 and MCT4 protein levels. The production of hydrogen peroxide (H2O2) and the mitochondrial membrane potential (∆Ѱm) stimulated by succinate in hippocampal homogenates were not significantly different between groups. ADP phosphorylation and the maximal respiratory rate induced by FCCP showed similar responses between groups, implying a normal mitochondrial function. Also, extracellular brain lactate levels were increased in the HPE group compared to other groups soon after performing the Y-maze task. However, such enhanced lactate levels were not associated with improved memory performance. In summary, hippocampal protein expression levels of MCT1 and 4 were increased by physical exercise and HP diet, whereas PDH was only increased by exercise. These observations indicate that a hippocampal metabolic reprogramming takes place in response to these environmental factors.
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Luis V
authors.initials: LV
authors.lastname: Portela
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Andressa W
authors.initials: AW
authors.lastname: Brochier
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Clarissa B
authors.initials: CB
authors.lastname: Haas
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Afonso Kopczynski
authors.initials: AK
authors.lastname: de Carvalho
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Jussania A
authors.initials: JA
authors.lastname: Gnoato
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.|Instituto do Cérebro (InsCer) do Rio Grande do Sul, Pontifícia Universidade Católica do Rio grande do Sul, Av. Ipiranga, 6690 - Bairro Jardim Botânico, Porto Alegre, RS, CEP: 90610.000, Brazil.
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Zimmer
authors.affiliation: Departamento de Bioquímica, ICBS, UFRGS. Programa de Pós Graduação em Ciências Biológicas- Bioquímica, Rua Ramiro Barcelos, 2600 anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Kalinine
authors.affiliation: Département de Physiologie, Université de Lausanne, Rue du Bugnon 7, 1005, Lausanne, Switzerland.
authors.forename: Luc
authors.initials: L
authors.lastname: Pellerin
authors.affiliation: Unidade de Ciências da Saúde, Laboratório de Bioquímica e Fisiologia do Exercício Universidade do Extremo Sul Catarinense-UNESC, Av. Universitária, 1105 - Bairro Universitário, Criciúma, Santa Catarina, CEP: 88806-000, Brazil. alexandrep.muller@gmail.com.
authors.forename: Alexandre P
authors.initials: AP
authors.lastname: Muller
mesh_terms: D000818:Animals; D004032:Diet; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008297:Male; D008810:Mice, Inbred C57BL; D027501:Monocarboxylic Acid Transporters / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D009457:Neuroglia / Q000378:metabolism*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D027981:Symporters / Q000378:metabolism
chemical_list: D027501:Monocarboxylic Acid Transporters; D009124:Muscle Proteins; D027981:Symporters; D006861:Hydrogen Peroxide
keywords: Hyperpalatable diet; Lactate; Mitochondrial function; Monocarboxylate transporters; Physical exercise