1
|
Shcherbakova K, Schwarz A, Ivleva I, Nikitina V, Krytskaya D, Apryatin S, Karpenko M, Trofimov A. Short- and long-term cognitive and metabolic effects of medium-chain triglyceride supplementation in rats. Heliyon 2023; 9:e13446. [PMID: 36825166 PMCID: PMC9941952 DOI: 10.1016/j.heliyon.2023.e13446] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 12/19/2022] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
Medium-chain triglycerides (MCT) possess neuroprotective properties. However, the long-term metabolic consequences of supplementing a regular diet with cognition-enhancing doses of MCT are largely unknown. We studied the effects of chronic (28 days) supplementation of regular diet with different doses of MCT oil (1, 3, or 6 g/kg/day) or water (control) on working memory (Y-maze), behavior in the Open Field, spatial learning (Morris water maze), and weight of internal organs in male Wistar 2.5-m.o. Rats. In a separate experiment, we evaluated acute (single gavage) and chronic (28 days) effects of MCT or lard supplementation (3 g/kg) on blood biochemical parameters. MCT-1 and MCT-3 doses improved working memory in YM. In MWM, MCT-6 treatment improved spatial memory. Chronic MCT-1 or MCT-3 treatment did not affect internal organ weight, while MCT-6 dose increased liver weight and the brown/white adipose tissue ratio. Acutely, MCT administration elevated blood β-hydroxybutyrate and malondialdehyde levels. Chronic MCT administration (3 g/kg) did not affect the blood levels of glucose, lactate, pyruvate, acetoacetate, β-hydroxybutyrate, total and HDL cholesterol, triglycerides, malondialdehyde, and aspartate transaminase and alanine transaminase activities. Therefore, daily supplementation of standard feed with MCT resulted in mild intermittent ketosis. It improved working memory at lower concentrations without significant adverse side effects. At higher concentrations, it improved long-term spatial memory but also resulted in organ weight changes and is likely unsafe. These results highlight the importance of monitoring the metabolic effects of MCT supplementation alongside cognitive assessment in future studies of MCT's neuroprotective properties.
Collapse
Affiliation(s)
- Ksenia Shcherbakova
- Laboratory of Neurobiology of the Brain Integrative Functions, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
- Corresponding author.
| | - Alexander Schwarz
- Laboratory of Molecular Mechanisms of Neuronal Interactions, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 44 Thorez Avenue, 194223, St. Petersburg, Russia
| | - Irina Ivleva
- Laboratory of Neurochemistry, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
| | - Veronika Nikitina
- Laboratory of Neurobiology of the Brain Integrative Functions, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
| | - Darya Krytskaya
- Laboratory of Neurobiology of the Brain Integrative Functions, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
| | - Sergey Apryatin
- Laboratory of Neurobiology of the Brain Integrative Functions, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
| | - Marina Karpenko
- Laboratory of Neurochemistry, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
| | - Alexander Trofimov
- Laboratory of Neurobiology of the Brain Integrative Functions, I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, 12 Akad. Pavlova St., 197022, St. Petersburg, Russia
- Corresponding author.
| |
Collapse
|
2
|
Shcherbakova K, Schwarz A, Apryatin S, Karpenko M, Trofimov A. Supplementation of Regular Diet With Medium-Chain Triglycerides for Procognitive Effects: A Narrative Review. Front Nutr 2022; 9:934497. [PMID: 35911092 PMCID: PMC9334743 DOI: 10.3389/fnut.2022.934497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/15/2022] [Indexed: 01/09/2023] Open
Abstract
It is now widely accepted that ketosis (a physiological state characterized by elevated plasma ketone body levels) possesses a wide range of neuroprotective effects. There is a growing interest in the use of ketogenic supplements, including medium-chain triglycerides (MCT), to achieve intermittent ketosis without adhering to a strict ketogenic diet. MCT supplementation is an inexpensive and simple ketogenic intervention, proven to benefit both individuals with normal cognition and those suffering from mild cognitive impairment, Alzheimer's disease, and other cognitive disorders. The commonly accepted paradigm underlying MCT supplementation trials is that the benefits stem from ketogenesis and that MCT supplementation is safe. However, medium-chain fatty acids (MCFAs) may also exert effects in the brain directly. Moreover, MCFAs, long-chain fatty acids, and glucose participate in mutually intertwined metabolic pathways. Therefore, the metabolic effects must be considered if the desired procognitive effects require administering MCT in doses larger than 1 g/kg. This review summarizes currently available research on the procognitive effects of using MCTs as a supplement to regular feed/diet without concomitant reduction of carbohydrate intake and focuses on the revealed mechanisms linked to particular MCT metabolites (ketone bodies, MCFAs), highlighting open questions and potential considerations.
Collapse
Affiliation(s)
- Ksenia Shcherbakova
- I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, Saint Petersburg, Russia,*Correspondence: Ksenia Shcherbakova
| | - Alexander Schwarz
- Laboratory of the Molecular Mechanisms of Neuronal Interactions, Institute of Evolutionary Physiology and Biochemistry (RAS), Saint Petersburg, Russia
| | - Sergey Apryatin
- I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, Saint Petersburg, Russia
| | - Marina Karpenko
- I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, Saint Petersburg, Russia
| | - Alexander Trofimov
- I.P. Pavlov Department of Physiology, Institute of Experimental Medicine, Saint Petersburg, Russia
| |
Collapse
|
3
|
Shcherbakova K, Nakayama H, Shimamoto N. Role of 100S ribosomes in bacterial decay period. Genes Cells 2015; 20:789-801. [PMID: 26290418 DOI: 10.1111/gtc.12273] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 06/17/2015] [Indexed: 11/30/2022]
Abstract
Ribosomal proteins S10 and S2 were each fused with GFP to track the fates of these proteins in the stationary growth phase and the following decay period in Escherichia coli. The fused proteins localized mainly in the cytoplasm, and their amounts were proportional to the colony-forming unit. S10-GFP strains that lacked genes responsible for regulating 100S ribosomes and S2-GFP strain that was unable to form 100S both showed shortened stationary phases. This result indicates that these strains exhibit earlier death in the absence of 100S formation (S2-GFP, S10-GFP∆rmf and S10-GFP∆hpf) and breakdown (S10-GFP∆yfiA). Therefore, in addition to the mere presence of 100S, the correct timing of 100S formation and breakdown is required to maintain viability. We propose a model in which 100S acts as a tentative repository of ribosomes that are protected from degradation and provide a source of amino acids in later growth period.
Collapse
Affiliation(s)
- Ksenia Shcherbakova
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-Ku, 603-8555, Kyoto, Japan
| | - Hideki Nakayama
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-Ku, 603-8555, Kyoto, Japan
| | - Nobuo Shimamoto
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita-Ku, 603-8555, Kyoto, Japan
| |
Collapse
|
4
|
Sotoyama H, Zheng Y, Iwakura Y, Mizuno M, Aizawa M, Shcherbakova K, Wang R, Namba H, Nawa H. Pallidal hyperdopaminergic innervation underlying D2 receptor-dependent behavioral deficits in the schizophrenia animal model established by EGF. PLoS One 2011; 6:e25831. [PMID: 22022452 PMCID: PMC3192134 DOI: 10.1371/journal.pone.0025831] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 09/12/2011] [Indexed: 11/18/2022] Open
Abstract
Epidermal growth factor (EGF) is one of the ErbB receptor ligands implicated in schizophrenia neuropathology as well as in dopaminergic development. Based on the immune inflammatory hypothesis for schizophrenia, neonatal rats are exposed to this cytokine and later develop neurobehavioral abnormality such as prepulse inhibition (PPI) deficit. Here we found that the EGF-treated rats exhibited persistent increases in tyrosine hydroxylase levels and dopamine content in the globus pallidus. Furthermore, pallidal dopamine release was elevated in EGF-treated rats, but normalized by subchronic treatment with risperidone concomitant with amelioration of their PPI deficits. To evaluate pathophysiologic roles of the dopamine abnormality, we administered reserpine bilaterally to the globus pallidus to reduce the local dopamine pool. Reserpine infusion ameliorated PPI deficits of EGF-treated rats without apparent aversive effects on locomotor activity in these rats. We also administered dopamine D1-like and D2-like receptor antagonists (SCH23390 and raclopride) and a D2-like receptor agonist (quinpirole) to the globus pallidus and measured PPI and bar-hang latencies. Raclopride (0.5 and 2.0 µg/site) significantly elevated PPI levels of EGF-treated rats, but SCH23390 (0.5 and 2.0 µg/site) had no effect. The higher dose of raclopride induced catalepsy-like changes in control animals but not in EGF-treated rats. Conversely, local quinpirole administration to EGF-untreated control rats induced PPI deficits and anti-cataleptic behaviors, confirming the pathophysiologic role of the pallidal hyperdopaminergic state. These findings suggest that the pallidal dopaminergic innervation is vulnerable to circulating EGF at perinatal and/or neonatal stages and has strong impact on the D2-like receptor-dependent behavioral deficits relevant to schizophrenia.
Collapse
Affiliation(s)
- Hidekazu Sotoyama
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Yingjun Zheng
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Yuriko Iwakura
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Makoto Mizuno
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Miho Aizawa
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Ksenia Shcherbakova
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Ran Wang
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Hisaaki Namba
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Hiroyuki Nawa
- Department of Molecular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
- * E-mail:
| |
Collapse
|