Elsevier

Journal of Psychiatric Research

Volume 81, October 2016, Pages 23-35
Journal of Psychiatric Research

Effect of folic acid on oxidative stress and behavioral changes in the animal model of schizophrenia induced by ketamine

https://doi.org/10.1016/j.jpsychires.2016.06.013Get rights and content

Abstract

Recent studies have shown benefits for the supplementation of folic acid in schizophrenic patients. The aim of this study was to evaluate the effects of folic acid addition on adult rats, over a period of 7 or 14 days. It also sets out to verify any potential protective action using an animal model of schizophrenia induced by ketamine, in behavioral and biochemical parameters. This study used two protocols (acute and chronic) for the administration of ketamine at a dose of 25 mg/kg (i.p.). The folic acid was given by oral route in doses of 5, 10 and 50 mg/kg, once daily, for 7 and/or 14 days in order to compare the protective effects of folic acid. Thirty minutes after the last administration of ketamine, the locomotor and social interaction activities were evaluated, and immediately the brain structure were removed for biochemical analysis. In this study, ketamine was administered in a single dose or in doses over the course of 7 days increasing the animal’s locomotion. This study showed that the administration of folic acid over 7 days was unable to prevent hyper locomotion. In contrast, folic acid (10 and 50 mg/kg) administrated over a period of 14 days, was able to partially prevent the hyper locomotion. Our data indicates that both acute and chronic administrations of ketamine increased the time to first contact between the animals, while the increased latency for social contact was completely prevented by folic acid (5, 10 and 50 mg/kg). Chronic and acute administrations of ketamine also increased lipid peroxidation and protein carbonylation in brain. Folic acid (10 and 50 mg/kg) supplements showed protective effects on the oxidative damage found in the different brain structures evaluated. All together, the results indicate that nutritional supplementation with folic acid provides promising results in an animal model of schizophrenia induced by ketamine.

Introduction

Folic acids one of the B complex vitamins which participates in the metabolism of one-carbon (C1) compounds (Coppen and Bolander-Gouaille, 2005, Mattson and Shea, 2003). This vitamin plays a neuro protective role against impairments in the central nervous system (CNS), and promotes neuronal growth and repair (Budni et al., 2011, Iskandar et al., 2004). Folic acid is also involved in the metabolism and functioning of compounds essential to the CNS, which includes the purines, pyrimidines, DNA, RNA, amino acids, phosphate compounds, vitamin B-12, methionine, S-adenosylmethionine, dopamine, adrenaline, noradrenaline and serotonin (Coppen and Bolander-Gouaille, 2005; Kronenberg et al., 2009; Lucock, 2011; ). Thus, alterations in the metabolism of folic acid can directly affect the CNS (Coppen and Bolander-Gouaille, 2005, Krebs et al., 2009, Miller, 2008, Stahl, 2007).

The presence of neuropsychiatric symptoms in patients with B deficiency vitamins complex and in children conceived following a short inter-pregnancy interval indicates a role for folic acid in schizophrenia. The influence of the interval between pregnancies could be explained by the reduction of the maternal reserves of folic acid when the maternal folic acid stores are still being replenished (Dogan et al., 2009).

Schizophrenia is a severe, chronic and debilitating mental disorder that affects 1% of the World’s population, and is characterized by positive (e.g. hallucinations), negative (e.g. blunted affects and social isolation) and cognitive symptoms (e.g. executive and memory dysfunction) (Larson et al., 2010). This disorder is considered to be the result of a genetic combination and environmental factors. Although its pathophysiology has not been fully determined, biological studies support that the involvement of several possible components, including altered DNA methylation, abnormal transmission of neurotransmitters, oxidative stress, folic acid deficiencies and high maternal homocysteine levels. Each of these factors has been separately explored, and they have all been found to involve C1 metabolism, which is a putative target-integrating gene–environment interactions by influencing epigenetic regulation (Krebs et al., 2009). Studies have indicated an important relationship between folic acid metabolism and schizophrenia. In this sense, these findings support the hypothesis that the deficiency of this vitamin during fetal development may be an important risking factor for schizophrenia (Gunawardana et al., 2011).

Current studies utilize pharmacological tools in evaluating the effects of new protective compounds against schizophrenia. Recent reviews have shown that ketamine is a useful tool for studying the positive, negative and cognitive symptoms observed in acute schizophrenia (Frohlich and Van Horn, 2014). This animal model of schizophrenia involves the acute or repeated administration of ketamine (Becker and Grecksch, 2004, Bubeníková-Valesová et al., 2008, Canever et al., 2010, De Oliveira et al., 2011). Ketamine is a dissociative anesthetic which acts as an NMDA receptor non competitive antagonist, and is largely used within research to create animal models of schizophrenia; since it induces schizophrenia-like symptoms (Dingledine et al., 1999). These animal models imitate the behavioral changes seen in schizophrenia such as hyperactivity, social interaction and memory deficits. Moreover, ketamine induces similar biochemical alterations that are found in schizophrenia, such NMDA receptor hypo function and oxidative stress (Chatterjee et al., 2011). Based on these previous results from our laboratory support the hypothesis that early insults interfere with the glutamatergic system, reflecting a greater sensitivity to the effects of ketamine in adulthood within an animal model of schizophrenia (Zugno et al., 2013). All these findings reinforce the validity of the ketamine model since it is capable to mimic the phenotype of schizophrenia in both, the animal behavior as well as in the biochemical alterations seen in brain.

Considering that the etiology of schizophrenia is not clear, current researches indicate that the accumulation of reactive oxygen species (ROS) is associated with the pathophysiology of the disorder (Ciobica et al., 2011, Ruiz-Litago et al., 2012, Yao and Keshavan, 2011). Oxidative stress occurs because of the increased levels of ROS, reactive nitrogen species (RNS) or by an imbalance in the activity of the endogenous antioxidant system (Berg et al., 2004, Kwon et al., 2003). As a consequence of the increased levels of ROS and the failure of the endogenous antioxidant system, damage to DNA, proteins and membrane lipids can occur (Konat, 2003, Kwon et al., 2003).

The link between schizophrenia and oxidative stress was recently demonstrated when it was shown that the activity of glutathione peroxides (GPx) decreased in both treated and untreated patients (Miljevic et al., 2010). Also, increased levels of markers for lipid per oxidation were observed in a similar population (Dadheech et al., 2008, Padurariu et al., 2010). Additionally, a study performed by our group suggested that the animal model of schizophrenia induced by ketamine showed changes in the activity of superoxide dismutase (SOD), catalase (CAT) and GPx, resulting in protein and lipid damage (De Oliveira et al., 2009).

Folic acid is involved in the metabolism of homocysteine that can be remethylated to methionine by enzymes that require folic acid, and it can also be catabolized by cystathionine-B-synthase, an enzyme dependent on the vitamin B6, that forms cysteine, a precursor of glutathione (Micle et al., 2012). It is known that hyperhomocysteinemia is directly related to oxidative stress. The autoxidation of homocysteine and other disulfides, releases oxygen (O2) and hydrogen peroxide (H2O2), both of them impair neuronal function and predispose the neuronal tissue to neurodegenerative and psychiatric disorders (White et al., 2001). Furthermore, the deficiency of folic acid induces the high levels of homocysteine and the formation of ROS that lead to decreases in both antioxidant potential and the activity of GPx, increasing oxidative tissue damage (McCully, 2009).

Although, studies have emphasized the association between folic acid deficiency and schizophrenia, few preclinical studies have been conducted to study the supplementation of this vitamin, or to evaluate its effect in an animal model of schizophrenia (Godfrey et al., 1990, Levine et al., 2006). In this sense, the aim of the study was to evaluate the effect of diet supplementation with folic acid over a period of seven or fourteen days in adult rats, and also to verify potential protective actions in an animal model of schizophrenia induced by acute or chronic administrations of ketamine on the animals behavioral and biochemical parameters.

Section snippets

Experimental procedures

The animals included in this study were handled according to the NIH Guide for the Care and Usage of Laboratory Animals, and also in accordance with the rules of the Brazilian Society for Neuroscience and Behavior (SBNeC). The experiments were performed at the Universidade do Extremo Sul Catarinense (UNESC) Brazil, in the Laboratory of Neurosciences, and in partnership with the Laboratory of Pathophysiology. All experimental procedures were performed in accordance with international

Behavioral tests

The results in Fig. 3A and B shows the effect of folic acid administration over a period of 7 and/or 14 days on the locomotor activity of rats in an animal model of schizophrenia induced by ketamine. Acute and chronic ketamine administration at a dose of 25 mg/kg increased the locomotor activity in these animals. Treatments with folic acid over a period of 7 days at doses of 5, 10 and 50 mg/kg were notable to prevent the hyper locomotor effect. In contrast, folic acid (10 and 50 mg/kg)

Discussion

In this study, ketamine administered in a single dose or over a period of 7 days increased the test animal’s levels of locomotion, corroborating previous studies proposed by Gama et al. (2012) and Zugno et al., (2013). Therefore, the administration of folic acid (5, 10 and 50 mg/kg) during a period of 7 days was unable to prevent hyperlocomotion in this experiment. It is possible that folic acid was not able to prevent the hyperlocomotion seen in this study due to the short period of time that

Role of the funding source

There are no conflict of interest. The funding agencies had no role in design and conduct of the study, the collection, management, analysis and interpretation of the data, or the preparation, review or approval of the manuscript. The authors were not paid to write this article by a pharmaceutical company or other agency.

Contributors

Drs Zugno, Budni, Quevedo and Schuck had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Zugno and Budni.

Acquisition of data:Wessler, Steckert, Mastella, De Oliveira, Damázio, Calixto, Pereira, Pedro.

Analysis and interpretation of data: Canever, Heylmann, Wessler and Pacheco.

Drafting of the manuscript: Canever and Budni.

Critical revision of the manuscript for importante

Acknowledgments

Laboratory of Neurosciences (Brazil) is one of the centers of the National Institute for Translational Medicine (INCT-TM) and one of the members of the Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC). This research was supported by grants from 1 CNPq, 2 InstitutoCérebro e Mente and 3 UNESC. JQ and AIZ are CNPq fellows.

References (76)

  • M. Gazal et al.

    Neuroprotective and antioxidant effects of curcumin in a ketamine- induced model of mania in rats

    Eur. J.Pharmacol.

    (2014)
  • P.S. Godfrey et al.

    Enhancement of recovery from psychiatric illness by methylfolate

    Lancet

    (1990)
  • M. Hill et al.

    folate supplementation in schizophrenia: a possible role for MTHFRgenotype

    Schizophr. Res.

    (2011)
  • M.J. Hunt et al.

    Ketamine dose-dependently induces high-frequency oscillations in the nucleus accumbens in freely moving rats

    Biol. Psychiatry

    (2006)
  • G. Imre et al.

    Dose-response characteristics of ketamine effect on locomotion, cognitive function and central neuronal activity

    Brain Res. Bull.

    (2006)
  • R. Joshi et al.

    Free radical scavenging behavior of folic acid: evidence for possible antioxidant activity

    Free Radic. Med.

    (2001)
  • A. Kale et al.

    Reduced folic acid, vitamin B12 and docosahexaenoicacid and increased homocysteine and cortisol in never-medicated schizophrenia patients: implications for altered one-carbon metabolism

    Psychiatry Res.

    (2010)
  • M.O. Krebs et al.

    One carbon metabolism and schizophrenia current challenges and future directions

    Trends Mol. Med.

    (2009)
  • R.L. Levine et al.

    Carbonyl assays for determination of oxidatively modified proteins

    Methods Enzymol.

    (1994)
  • J. Levine et al.

    Homocysteine-reducing strategies improve symptoms in chronic schizophrenic patients with hyperhomoysteinemia

    Biol. Psychiatry

    (2006)
  • O.H. Lowry et al.

    Protein measurement with the Folin phenol reagent

    J. Biol. Chem.

    (1951)
  • M.P. Mattson et al.

    Folate and homocysteine metabolism in neural plasticity and neurodegenerative disorders

    Trends Neurosci.

    (2003)
  • C. Miljevic et al.

    Lipid status, anti-oxidant enzyme defence and haemoglobin content in the blood of long-term clozapine-treated schizophrenic patients

    Prog. Neuropsychopharmacol. Biol. Psychiatry

    (2010)
  • R.J.M. Niesink et al.

    Involvement of opioid and dopaminergic systems in isolation-induced pinning and social grooming of young rats

    Neuropharmacology

    (1989)
  • M. Padurariu et al.

    Evaluation of antioxidant enzymes activities and lipid peroxidation in schizophrenic patients treated with typical and atypical antipsychotics

    Neurosci. Lett.

    (2010)
  • C.D. Pandya et al.

    Antioxidants as potential therapeutics for neuropsychiatric disorders

    Prog. Neuropsychopharmacol. Biol. Psychiatry

    (2013)
  • F. Ruiz-Litago et al.

    Adaptive response in the antioxidant defence system in the course and outcome in first-episode schizophrenia patients: a 12-months follow-up study

    Psychiatry Res.

    (2012)
  • S. Shamsi et al.

    Cognitive and symptomatic predictors of functional disability in schizophrenia

    Schizophr. Res.

    (2011)
  • R. Tandon et al.

    Schizophrenia, ‘Just the Facts’ 4.Clinical features and conceptualization

    Schizophr. Res.

    (2009)
  • A. Wendel

    Glutathioneperoxidase

    Methods Enzymol.

    (1981)
  • B.T. Wu et al.

    Low plasma vitamin B-12 is associated with a lower pregnancy-associated rise in plasma free choline in Canadian pregnant women and lower post natal growth rates in their male infants

    Am. J.Clin. Nutr.

    (2013)
  • A.I. Zugno et al.

    Effect of maternal deprivation on acetylcholinesterase activity and behavioral changes on the ketamine-induced animal model of schizophrenia

    Neuroscience

    (2013)
  • M. Arai et al.

    Carbonyl stress-related schizophrenia perspective on future therapy and hypotheses regarding pathophysiology of schizophrenia

    SeishinShinkeigakuZasshi

    (2012)
  • J.V. Bannister et al.

    Assays for superoxide dismutase

    Methods Biochem. Anal

    (1987)
  • D. Berg et al.

    Redox imbalance

    Cell. Tissue Res.

    (2004)
  • O.S. Brocardo et al.

    Folic acid administration prevents ouabain-induced hyperlocomotion and alterations in oxidative stress markers in the rat brain

    Bipolar Disord.

    (2010)
  • L. Canever et al.

    A rodent model of schizophrenia reveals increase in creatine kinase activity with associated behavior changes

    Oxid. Med. Cell. Longev.

    (2010)
  • J.G. Chen et al.

    Reversal of aging-associated hippocampal synaptic plasticity deficits by reductants via regulation of thiol redox and NMDA receptor function

    Aging Cell

    (2011)
  • Cited by (0)

    View full text