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Article

Regulation of Genes Related to Cognition after tDCS in an Intermittent Hypoxic Brain Injury Rat Model

by
Jin-Won Lee
1,
Won-Hyeong Jeong
1,
Eun-Jong Kim
2,
Insung Choi
1,* and
Min-Keun Song
1,2,*
1
Department of Physical & Rehabilitation Medicine, Chonnam National University Hospital, 42 Jebong-ro, Dong-gu, Gwangju 61479, Korea
2
Department of Physical & Rehabilitation Medicine, Chonnam National University Medical School, 160, Baekseo-Ro, Dong-Gu, Gwangju 61469, Korea
*
Authors to whom correspondence should be addressed.
Genes 2022, 13(10), 1824; https://doi.org/10.3390/genes13101824
Submission received: 8 September 2022 / Revised: 7 October 2022 / Accepted: 7 October 2022 / Published: 9 October 2022
(This article belongs to the Section Molecular Genetics and Genomics)
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Abstract

:
Background: Hypoxic brain injury is a condition caused by restricted oxygen supply to the brain. Several studies have reported cognitive decline, particularly in spatial memory, after exposure to intermittent hypoxia (IH). However, the effect and mechanism of action of IH exposure on cognition have not been evaluated by analyzing gene expression after transcranial direct current stimulation (tDCS). Hence, the purpose of this study was to investigate the effects of tDCS on gene regulation and cognition in a rat model of IH-induced brain injury. Methods: Twenty-four 10-week-old male Sprague–Dawley rats were divided into two groups: IH exposed rats with no stimulation and IH-exposed rats that received tDCS. All rats were exposed to a hypoxic chamber containing 10% oxygen for twelve hours a day for five days. The stimulation group received tDCS at an intensity of 200 µA over the frontal bregma areas for 30 min each day for a week. As a behavior test, the escape latency on the Morris water maze (MWM) test was measured to assess spatial memory before and after stimulation. After seven days of stimulation, gene microarray analysis was conducted with a KEGG mapper tool. Results: Although there were no significant differences between the groups before and after stimulation, there was a significant effect of time and a significant time × group interaction on escape latency. In the microarray analysis, significant fold changes in 12 genes related to neurogenesis were found in the stimulation group after tDCS (p < 0.05, fold change > 2 times, the average of the normalized read count (RC) > 6 times). The highly upregulated genes in the stimulation group after tDCS were SOS, Raf, PI3K, Rac1, IRAK, and Bax. The highly downregulated genes in the stimulation group after tDCS were CHK, Crk, Rap1, p38, Ras, and NF-kB. Conclusion: In this study, we confirmed that SOS, Raf, PI3K, Rac1, IRAK, and Bax were upregulated and that CHK, Crk, Rap1, p38, Ras, and NF-kB were downregulated in a rat model of IH-induced brain injury after application of tDCS.

1. Introduction

Approximately 30–50% of children with hypoxic brain injury are known to have developmental delays accompanied by neurologic symptoms [1], and patients who experience severe bleeding during cardiac or aortic surgery also experience hypoxic–ischemic brain damage and neurological decline even after recovery [2].
Exposure to intermittent hypoxia (IH) exposure in obstructive sleep apnea syndrome may cause cognitive decline due to apoptosis of neurons in the cortex and hippocampus [3,4,5]. Several studies have reported cognitive decline, particularly in spatial memory, after IH exposure [6,7,8,9,10].
Transcranial direct current stimulation (tDCS) may facilitate cortical neuroplasticity [11]. One of the mechanisms of the effect of tDCS is to modulate cortical excitability by reducing GABA and glutamatergic neuronal activity [12]. However, the effect of tDCS on cognition is debated. Several studies have shown that tDCS is effective in improving various cognitive functions in aged people [13,14]. However, there are a few reports describing the neutral or negative effects of tDCS on cognition [15,16]. Some clinical studies have reported that tDCS is ineffective at improving memory and executive function [17,18].
The effect and mechanism of action of tDCS on cognition have not been evaluated by analyzing gene expression after tDCS in IH-induced brain injury. The purpose of this study was to investigate the effect of tDCS on gene regulation and cognition in a rat model of IH-induced brain injury.

2. Materials and Methods

2.1. Experimental Subjects

The experimental subjects were 10-week-old male Sprague-Dawley rats (Samtako Co., Osan, Korea) weighing 300 ± 50 g. All subjects were housed under regular circumstances in the University Animal Care Laboratory. The study protocol was approved by the Institutional Animal Ethics of University Animal Care and Committee (CNUH IACUC-18018), and all experimental procedures followed the guidelines of the IACUC.
A total of 24 rats were randomly separated into two groups: a control group (n = 12) and a stimulation group (n = 12). After being exposed to 12 h/day in a hypoxic chamber with a 10% oxygen concentration for five days, the control rats were exposed at normal oxygen concentrations to compare their spontaneous recovery and application of tDCS.

2.2. Methods

The study was sequentially performed as scheduled (Figure 1). Twenty-four 10-week-old rats were subjected to acclimatization for three days. Next, pretraining with the Morris water maze (MWM) was performed for three consecutive days. Hypoxic brain injury was induced over five days. tDCS stimulation was conducted the day after the end of hypoxic brain injury induction. tDCS was applied for seven days. All the rats were sacrificed the day after the end of the experiment, and hippocampal tissues were extracted for RNA sequencing.

2.2.1. Hypoxic Brain Injury Rat Model

The rat model of hypoxic brain injury was induced with a hypoxic chamber (Figure 2). Animals rested for 12 h/day (n = 24) in one identical commercially designed chamber (30 × 320 × 320 inches) for five days under conditions with 10% oxygen concentration. Deviations from the desired oxygen concentration were corrected by the addition of N2 through solenoid valves. The humidity was measured and maintained at 40–50% by circulating gas through the freezer and using silica gel. The ambient temperature was kept at 22–24 °C [19].

2.2.2. Transcranial Direct Current Stimulation

For tDCS, we used a battery-driven, constant-current stimulator (HDC manufactured by Newronika s.r.l., Italy, and distributed by Magstim Co. Ltd., Whitland, Wales, UK). For the two-channel anodal method, cup-shaped active electrodes (1 cm × 1 cm) were placed on the frontal bregma area; in contrast, for the cathodal method, a 0.5-cm sponge pad was applied to the neck (Figure 2). Electrical stimulation was applied at an intensity of 200 μA for 30 min over a period of seven consecutive days.

2.2.3. Neurocognitive Behavioral Test

Evaluation of spatial learning and memory was assessed through the MWM test developed by Morris et al. [20]. All the methods for the MWM test were performed according to the methods of a previous study [21]. The tests were conducted in a circular pool with a diameter of 184 cm and a height of 60 cm. The pool was filled with water and maintained at 22 ± 2 °C. The pool was virtually divided into four quadrants, and one quadrant was set as the target. Visual symbols were assigned to the perimeter of each quadrant. A circular escape platform (diameter, 10 cm; height, 38 cm) was positioned in the center of the target quadrant. A platform was submerged one centimeter below the water level.
All groups underwent pretraining for three consecutive days before inducing hypoxic brain injury. The animals were randomly placed in the water maze facing the maze wall entry points and distributed evenly around the perimeter of the maze. After finding the platform, the rats stayed there for 10 s until the next experiment. If the rat could not find the hidden platform within 120 s, the rat was placed on the platform for 15 s so that it could recognize the location of the platform. The rat was displaced from the pool and placed back in its cage for five minutes. Then, the second trial was performed.
The MWM test was performed to evaluate spatial memory on the day after stimulation. The rats tried to find the platform below the surface of the water within 300 s. The escape latency (time taken to reach the platform) was automatically calculated by an Ethovision Color-Pro® video tracking system (Nodulus, Wageningen, The Netherlands).

2.2.4. RNA Sequencing Analysis

All the methods of RNA sequencing were performed according to the methods of a previous study [22]. After sacrifice, hippocampal tissues from all rats were extracted for RNA sequencing.

RNA Isolation

Total RNA was isolated using TRIzol reagent (Invitrogen, Waltham, MA, USA). Assessment of RNA quality was performed with an Agilent 2100 bioanalyzer using the RNA 6000 Nano Chip (Agilent Technologies, Amstelveen, The Netherlands), and RNA quantification was performed using an ND-2000 Spectrophotometer (Thermo Inc., Waltham, MA, USA).

Library Preparation and Sequencing

For control and test RNAs, library construction was performed according to the manufacturer’s instructions using QuantSeq 3′ mRNA-Seq Library Prep Kit (Lexogen, Inc., Wien, Austria). In summary, 500 ng of total RNA was prepared, oligo-dT primers containing an Illumina-compatible sequence at the 5′ end were hybridized to the RNA, and reverse transcription was performed. The second-strand synthesis was started using random primers with an Illumina-compatible linker sequence at the 5′ end after the degradation of the RNA template. The double-stranded libraries were purified using magnetic beads to remove all reaction components. The library was amplified to add the full adapter sequences required for cluster generation. The finished library was purified from PCR components. High-throughput sequencing was performed as single-ended 75 sequencing using NextSeq 500 (Illumina, Inc., San Diego, CA, USA).

Data Analysis

QuantSeq 3′ mRNA-Seq reads were aligned using Bowtie2 [23]. Bowtie2 indices were generated from genome assembly sequences or representative transcript sequences for alignment to the genome and transcriptome. The alignment files were used to assemble transcripts, estimate their amounts, and detect differential expression of genes. Differentially expressed genes were determined based on the counts of unique and multiple alignments using Bedtools’ coverage [24]. Read count (RC) data were processed according to the Quantile normalization method using EdgeR within R using Bioconductor [25]. Gene classification was set using the DAVID (the Database for Annotation, Visualization, and Integrated Discovery, https://david.ncifcrf.gov/, accessed at 26 October 2021) and Medline databases. Then, the neurotrophin signaling pathway was elicited with the KEGG mapper–Search & Color Pathway (http://www.genome.jp/kegg/tool/map_pathway2.html, accessed at 26 October 2021) to put the Entrez ID and input data.

3. Statistical Analysis

The sample size of this study was calculated according to Cohen’s formula [26], and the effect size was set to 0.95 based on the large-sized F-value. The number of groups was set to 2, the number of measures was set to 2, the effect size was set to 0.95, the significance level was set to 0.05, and the statistical power was set to 0.70. The total sample size required for repeated-measures ANOVA (interaction of time with the group), calculated using G * power [27], was 24.
All statistical analyses were performed using SPSS for Windows (version 26.0; Chicago, IL, USA), and all data are presented as the mean ± standard deviation (SD). Escape latency and velocity were analyzed by one-way ANOVA, repeated-measures ANOVA, and subsequent post hoc tests.

4. Results

4.1. Neurocognitive Behavioral Test

The escape latency on the MWM test before tDCS stimulation was 93.33 ± 38.92 s and 104.26 ± 21.53 s for the control and stimulation groups. There was no significant difference between the two groups before tDCS stimulation (p = 0.404). The escape latency on the MWM test after tDCS stimulation was 79.92 ± 36.61 s and 50.94 ± 37.07 s for the control and stimulation groups, respectively. There was no significant difference between the two groups after tDCS stimulation (p = 0.067). The escape latency on the MWM test was also analyzed by ANOVA with test time as a repeated measure. The results showed a significant change over time (F = 12.451, p = 0.002) and a significant time × group interaction (F = 4.452, p = 0.046) (Figure 3). tDCS has an effect on cognitive functioning, as demonstrated by statistically significant changes in escape latency and the time differences between the stimulation and control groups.

4.2. RNA Sequencing Data

QuantSeq RNA analysis revealed 17,312 gene symbols. Then, symbols with significant fold changes in the stimulation group compared with the control group were identified. Significant fold changes of 180 genes were shown in the tDCS stimulation group (p < 0.05, fold change > 2 times, average of normalized read counts (RCs) > 6 times) (Table 1). Whole sequencing data was included in Supplementary Materials.

4.3. KEGG Mapper Tool Analysis

After tDCS, neurotrophin signaling pathways were analyzed with a KEGG mapper tool. Compared with the control group, the upregulated genes in the stimulation group after tDCS were SOS, Raf, PI3K, Rac1, IRAK, and Bax (p < 0.05). Compared with the control group, the downregulated genes in the stimulation group after tDCS were CHK, Crk, Rap1, p38, Ras, and NF-kB (p < 0.05) (Figure 4).

5. Discussion

In this study, RNA sequence analysis was performed after tDCS stimulation in a rat model of IH-induced injury. In a previous study, a neurogenesis induction effect of tDCS after experimental stroke was observed at the cellular level [28]. To examine the expression changes in the transcriptome related to this effect, the neurotrophin signaling pathway, which is related to neurogenesis, was selected from among the enriched pathways in the KEGG analysis. Among the genes corresponding to this pathway, six genes (SOS, Raf, PI3K, Rac1, IRAK, and Bax) were upregulated, and six genes (CHK, Crk, Rap1, p38, Ras, and NF-kB) were downregulated.
The neurotrophin signaling pathway is a pathway activated by neurotrophin, a protein that controls the function of neurons in many ways. Four types of neurotrophin are known, which are nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4). These neurotrophins are essential for maintaining the survival, morphology, and differentiation of normal neurons, and have various roles, such as synaptic function control and plasticity control. This pathway consists of two types of receptors: tropomyosin-related kinase (Trk) receptor and p75 neurotrophin receptor (p75NTR). When neurotrophin binds to these receptors, each downstream pathway is activated [29].
The Trk receptor-mediated pathway almost always promotes neuronal survival and differentiation, and there are three major intracellular signaling pathways. The first is the mitogen-activated protein (MAP) kinase cascade by Ras activation, which is a pathway that promotes neuronal differentiation. In this study, Son of Sevenless (SOS) and Raf were found to be upregulated among the genes involved in this pathway, but Ras and p38 were downregulated. SOS acts as a Ras exchange factor, and Raf phosphorylates Mek1 and Mek2 to phosphorylate and activate Erk1 and Erk2. Furthermore, Ras plays an important role in promoting neuronal differentiation by stimulating signaling of the c-Raf-Erk, p38MAP kinase, and class I phosphatidyl inositol-3 (PI3) kinase pathways. P38MAP kinase is responsible for the phosphorylation of cyclic AMP response element binding protein (CREB) by activating MAP kinase-activated protein kinase-2 (MK-2).
Interestingly, among the intermediate genes of this MAPK pathway, SOS and Raf were upregulated, but Ras and p38 were downregulated. This finding suggests that tDCS affects neuronal differentiation in IH-induced injury, but to confirm this effect, further studies including immunohistochemical analyses should be performed by selecting candidate genes coding for the neuronal differentiation process. In a previous study, cathodal tDCS was found to induce upregulation of osteopontin (OPN) [10], which is known to increase neuronal differentiation of neural stem cells after cerebral ischemia [30]. In this study, by applying anodal tDCS after exposure to IH, the MAPK pathway was found to play an important role as another tDCS-regulated pathway that affects neuronal differentiation.
On the other hand, among the genes in the Crk-C3G-Rap1 signaling pathway, which is a minor pathway that sustains the activation of MAPK, Crk, and Rap1 were downregulated. The result that both genes were downregulated is not in the same direction as our previous hypothesis, but tDCS may act to inhibit the MAPK cascade in IH conditions.
The second Trk receptor-mediated pathway is the PI3 kinase pathway, which promotes neuronal survival. Among the genes in this pathway, PI3K was upregulated, but CHK and NF-kB were downregulated. When PI3K is activated, Akt is activated along the lower signaling pathway, and eventually, IkB is degraded to release NF-kB, which promotes neuronal survival. CHK acts as a signaling molecule that is recruited to the Trk receptor. PI3K, CHK, and NF-kB showed regulation in the opposite direction; furthermore, in the abovementioned upregulation of OPN by cathodal tDCS [10], OPN also enhanced the survival of neural stem cells [30]. Therefore, the effect of anodal tDCS on the PI3K pathway and neuronal survival also needs to be further studied.
The third Trk receptor-mediated pathway is the phospholipase C-r1 (PLC-r1) pathway that promotes synaptic plasticity. In the results of this study, there were no significantly regulated genes belonging to this pathway. This may be related to the fact that, unlike other pathways mediated by the Trk receptor, the PLC-r1 pathway is considered to have undergone adaptation to be integrated into the Trk receptor during the evolution process [31].
The p75NTR-mediated pathway promotes neuronal apoptosis, and there are several major intracellular signaling pathways. One of them is the Jun kinase pathway, and signaling of this pathway leads to p53 activation and apoptosis. In the results of this study, Rac1 and Bax were upregulated among the genes involved in this pathway. Rac1 plays an essential role in p75NTR-mediated apoptosis, particularly in oligodendrocytes [32]. Bax is a pro-apoptotic gene activated by p53. From the results of the upregulation of these two genes, it can be expected that tDCS in IH conditions would have the effect of promoting apoptosis through JNK signaling. Previous studies have reported that tDCS influences the apoptotic process. In ischemic mice, cathodal tDCS reduced the number of caspase-3-positive cells, which represent apoptotic cells, but anodal stimulation increased the same [33]. Anti-apoptotic proteins have been reported to be upregulated in fibroblasts exposed to electrical fields in vitro [34].
Another pathway is the NF-kB pathway, which induces neuronal survival. Among the genes of this pathway, interleukin-1 receptor-associated kinase (IRAK) was upregulated, but NF-kB was downregulated. IRAK is recruited to the complex formed by Traf6 and p75NTR to phosphorylate IkB and release NF-kB. IRAK and NF-kB also showed conflicting regulation; thus, further research is needed.
According to a previous study, the gene expression pattern and magnitude of the response depend on the tDCS current intensity [35]. Therefore, further studies, including tDCS stimulation with various current intensities, are needed for genes belonging to the neurotrophin signaling pathway, including the MAPK, PI3K, and NF-kB pathways, which showed contradictory changes in gene regulation in this study.
However, this study had a small effect size, and the findings do not apply to humans as it was an animal study. Other limitations were the lack of a sham stimulation group for applying tDCS and the lack of quantitative data for selected genes, such as real-time PCR or western blot analysis, which was not supported. Further studies are needed to identify the effective therapeutic intensity of tDCS that may enhance neuroplasticity in irreversible hypoxic brain injury.

6. Conclusions

After the tDCS experiment, significant fold changes in 12 genes related to neurogenesis in rats with IH-induced brain injury after tDCS were shown. Therefore, regulated gene biomarkers related to cognition may be helpful in predicting the effect of tDCS in rats with IH-induced brain injury.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/genes13101824/s1, Whole sequencing data in supplementary materials. Supplementary Materials: Fold changes in whole genes with significant fold changes.

Author Contributions

Conceptualization, I.C. and M.-K.S.; Data curation, E.-J.K.; Formal analysis, W.-H.J.; Funding acquisition, M.-K.S.; Investigation, M.-K.S.; Methodology, E.-J.K.; Project administration, M.-K.S.; Resources, J.-W.L.; Supervision, I.C.; Visualization, J.-W.L.; Writing—original draft, J.-W.L.; Writing—review & editing, I.C. and M.-K.S. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by National Research Foundation of Korea (NRF-2019R1F1A1062089) and The APC was funded by a grant (BCRI-21032) from Chonnam National University Hospital Biomedical Research Institute.

Institutional Review Board Statement

The study protocol was approved by the Institutional Animal Ethics of University Animal Care and Committee (CNUH IACUC-18018).

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available on request from the corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 1. Schematic representation of the experiment.
Figure 1. Schematic representation of the experiment.
Genes 13 01824 g001
Genes 13 01824 g002 550
Figure 2. Modeling hypoxic brain injury in a rat with a hypoxic chamber and transcranial direct current stimulation (tDCS). A cup-shaped active electrode (1 cm × 1 cm) was placed on the frontal bregma area. For the cathodal method, a 0.5 cm sponge pad was applied to the neck. Electrical stimulation was applied at an intensity of 200 μA for 30 min over a period of seven consecutive days.
Figure 2. Modeling hypoxic brain injury in a rat with a hypoxic chamber and transcranial direct current stimulation (tDCS). A cup-shaped active electrode (1 cm × 1 cm) was placed on the frontal bregma area. For the cathodal method, a 0.5 cm sponge pad was applied to the neck. Electrical stimulation was applied at an intensity of 200 μA for 30 min over a period of seven consecutive days.
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Genes 13 01824 g003 550
Figure 3. Escape latency on the hidden platform trial on the Morris-water maze (MWM) test. The escape latency on the MWM test before tDCS stimulation was 93.33 ± 38.92 s and 104.26 ± 21.53 s in the control and stimulation groups, respectively. The escape latency on the MWM test after tDCS stimulation was 79.92 ± 36.61 s and 50.94 ± 37.07 s in the control and stimulation groups, respectively. There were no significant differences between the two groups before and after tDCS stimulation (p = 0.404, 0.067). However, the results showed a significant change over time (F = 12.451, p = 0.002) and a significant time × group interaction (F = 4.452, p = 0.046). As evidenced by the statistically significant changes in escape latency and time difference between the two groups, tDCS may affect cognitive function. * p < 0.05.
Figure 3. Escape latency on the hidden platform trial on the Morris-water maze (MWM) test. The escape latency on the MWM test before tDCS stimulation was 93.33 ± 38.92 s and 104.26 ± 21.53 s in the control and stimulation groups, respectively. The escape latency on the MWM test after tDCS stimulation was 79.92 ± 36.61 s and 50.94 ± 37.07 s in the control and stimulation groups, respectively. There were no significant differences between the two groups before and after tDCS stimulation (p = 0.404, 0.067). However, the results showed a significant change over time (F = 12.451, p = 0.002) and a significant time × group interaction (F = 4.452, p = 0.046). As evidenced by the statistically significant changes in escape latency and time difference between the two groups, tDCS may affect cognitive function. * p < 0.05.
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Figure 4. KEGG Mapper Tool Analysis. This figure represents the neurotrophin signaling pathway after tDCS (coral: upregulation, blue: downregulation). Compared with the control group, the upregulated genes in the stimulation group after tDCS were SOS, Raf, PI3K, Rac1, IRAK, and Bax (p < 0.05). Compared with the control group, the downregulated genes in the stimulation group after tDCS were CHK, Crk, Rap1, p38, Ras, and NF-kB (p < 0.05).
Figure 4. KEGG Mapper Tool Analysis. This figure represents the neurotrophin signaling pathway after tDCS (coral: upregulation, blue: downregulation). Compared with the control group, the upregulated genes in the stimulation group after tDCS were SOS, Raf, PI3K, Rac1, IRAK, and Bax (p < 0.05). Compared with the control group, the downregulated genes in the stimulation group after tDCS were CHK, Crk, Rap1, p38, Ras, and NF-kB (p < 0.05).
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Table
Table 1. Fold changes in 180 genes with significant fold changes.
Table 1. Fold changes in 180 genes with significant fold changes.
IDGene SymbolFold Change
(Stimulation/Control)		Average Normalized Read Counts
ControlStimulation
212Actr102.0255.6736.692
216Actr32.2596.0087.183
317Adh52.3184.8896.102
331Ado5.9463.4836.055
358Aes0.4468.4127.247
867Arl20.1876.4464.028
879Arl6ip50.4166.6675.401
910Arpp194.0046.6778.679
1019Atg32.2164.9596.106
1038Atox10.0906.2652.796
1052Atp1b20.4546.2765.138
1094Atp6v0e20.3287.2015.595
1127Aurkaip12.7594.7296.193
1204Basp10.4449.2258.054
1228Bcas10.4667.6326.531
1439Bud310.4726.1355.053
1453C1ql30.4186.2564.999
1458C1qtnf40.3647.1975.738
1605Capzb0.4937.0446.024
1679Cbx32.4585.9807.278
1952Cdc372.1215.7766.861
2018Cdk5r10.4856.3465.304
2019Cdk5r20.2306.8104.692
2204Chmp2a0.2026.0853.778
2224Chrm10.4506.5425.389
2411Cltb0.3716.6665.234
2611Cox6c0.5009.5438.543
2703Crip13.8374.0726.012
2704Crip20.3236.1334.503
2748Crym0.3416.1744.622
2867Ctxn10.4468.1727.006
2919Cyb5a0.3916.3544.999
3061Dbp0.1426.4303.618
3129Ddt2.0606.0457.088
3251Dgcr60.2046.0533.756
3412Dnal10.2756.2064.344
3546Dusp10.4966.0054.992
3585Dynlrb10.3988.4647.135
3650Eef1b20.3707.7506.315
3715Eif1b0.4676.9695.870
3827Enah2.4915.2006.517
3834Enho0.2936.3064.536
3893Epn10.4026.7215.406
3950Esd2.1185.4376.519
4117Fam162a0.0156.5790.526
4235Fam96b0.4266.0724.841
4296Fbxo20.4946.0395.023
4392Fgf122.3176.1527.364
4453Fkbp1b0.0136.2280.000
4454Fkbp20.4647.4446.336
4455Fkbp30.4487.2126.055
4586Ftl10.4517.9566.808
4976Gnb2l10.4266.9375.705
4984Gng130.1727.1784.639
5010Golga72.1045.4346.507
5233Gsn0.4846.2925.246
5252Gstm70.4557.1315.996
5311Guk10.4677.6436.544
5384Hbb-b12.2645.7756.954
5504Hist1h1d0.3527.3875.880
5513Hist1h2bh0.2337.1065.003
5517Hist1h4b0.3267.8986.281
5518Hist1h4m0.1948.3786.009
5519Hist2h2ab0.0576.6882.553
5520Hist2h3c20.2677.4005.494
5521Hist2h40.1769.2796.775
5523Hist3h2ba0.4006.0364.713
5542Hmga10.0156.0720.000
5660Hrsp123.4594.2926.083
5762Hypk0.3007.5425.806
6076Isca25.0584.1076.445
6123Itm2a2.4774.9376.245
6174Junb0.3526.5295.022
6209Kcna12.0365.1506.176
6243Kcnh52.3144.8696.079
6249Kcnip30.3716.1644.733
6495Kpna32.4774.7136.022
6577LOC1001348712.1516.5727.677
6647LOC1009111770.0096.8690.000
6684LOC257642125.8520.0126.988
6775LOC49875016.4862.3606.404
6916LOC6908710.0126.4190.000
6928LOC6918070.4626.0414.928
6941Lage30.4746.4765.399
6960Lamtor52.0665.3396.386
7371Ly6h0.4196.5845.328
7448Maf12.2404.9836.146
7602Matk0.3796.1344.734
7841Micu30.4096.2925.002
7874Mir11882102.7240.01311.051
7886Mir125b10.00011.7240.000
7910Mir140310.1840.0138.290
7945Mir1861655.0800.01310.706
8071Mir3410.0019.4690.000
8236Mir63200.0126.4070.000
8302Mir92b0.00011.0660.000
8524Mrpl490.3266.0644.448
8538Mrps18a2.3775.3496.598
8709Myeov20.2947.7035.934
8732Myl60.4278.8817.654
8734Myl6l92.8380.0126.549
8934Ndufb20.1947.8825.516
8936Ndufb40.4738.4567.376
8939Ndufb70.1606.9864.347
8948Ndufs63.3825.1806.938
8953Ndufv30.3686.4154.974
8989Nenf0.1716.3733.828
9160Nop104.9643.9256.237
11011Pdcd42.0465.4736.506
11071Pdp13.0455.2026.808
11111Penk0.2416.0594.004
11141Pfdn20.3187.0265.375
11151Pfn10.4287.2406.017
11235Phyhipl0.4436.5625.387
11297Pink10.2936.7694.999
11321Pja12.0626.3407.384
11406Plekhb10.4627.1716.056
11492Pnp0.2066.1513.875
11541Polr2f0.4246.6075.368
11557Polr3k0.3906.1034.745
11754Prdx50.4347.9196.714
11955Psd0.4906.3845.356
11973Psma60.3306.5374.937
11979Psmb22.2025.1066.245
11984Psmb70.4577.5836.454
12335RGD15599090.1956.2373.876
12620Rac12.0166.1067.118
12669Rap1b0.3956.1214.780
12845Rer14.6713.8636.087
12902Rgs53.0174.6426.236
12965Rims43.6364.7086.570
12991Rmrp0.40715.74814.450
12993Rn18s11049.6390.01413.445
12994Rn28s12992.7480.01413.679
12995Rn45s446.8630.0138.817
13133Rpl120.2718.3396.458
13135Rpl13a0.4499.5628.409
13138Rpl170.3809.1957.800
13147Rpl240.4459.3578.188
13173Rpl60.4208.4867.234
13178Rplp00.4748.1507.073
13196Rps110.4718.7427.656
13201Rps15a0.2589.4957.543
13202Rps160.4849.0558.008
13203Rps170.4449.0837.911
13236Rps80.4789.4288.363
13335S100a1115.4780.0136.865
13338S100a130.2686.7294.831
13390Sarnp2.0914.9506.013
13414Sc5d2.2185.0116.160
13424Scand12.1515.0156.119
13479Scrg12.6205.9757.364
13510Sdhb0.4456.4225.254
13774Shfm10.4656.3575.253
13824Sirt52.0775.5386.593
14346Snrnp702.4775.4956.803
14353Snrpd20.2897.4105.622
14356Snrpg0.1736.4353.902
14378Snx23.7484.5446.450
14532Spin10.4906.2565.226
14570Sprn2.5304.9936.332
14672Sst0.3477.9166.389
14678Ssu720.3426.3914.845
14754Stk243.2484.5546.254
14928Synpr0.4646.2435.136
15017Taldo10.3036.7415.018
15096Tbca0.3936.8025.455
15142Tceb20.4707.9536.864
15169Tctex1d25.9603.6086.183
15478Tmem14a2.1415.0306.128
15738Top12.1715.0306.149
16059Ttc9b0.1017.0373.726
16211Ubl50.4207.9836.730
16309Upf3a2.2024.9246.063
16321Uqcr110.4458.9377.770
16336Use10.3296.1174.512
16411Vamp12.0646.2387.283
16698Vti1a4.7134.1156.352
17307mrpl113.1924.3996.074
17310rnf1419.1363.5286.720
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Lee, J.-W.; Jeong, W.-H.; Kim, E.-J.; Choi, I.; Song, M.-K. Regulation of Genes Related to Cognition after tDCS in an Intermittent Hypoxic Brain Injury Rat Model. Genes 2022, 13, 1824. https://doi.org/10.3390/genes13101824

AMA Style

Lee J-W, Jeong W-H, Kim E-J, Choi I, Song M-K. Regulation of Genes Related to Cognition after tDCS in an Intermittent Hypoxic Brain Injury Rat Model. Genes. 2022; 13(10):1824. https://doi.org/10.3390/genes13101824

Chicago/Turabian Style

Lee, Jin-Won, Won-Hyeong Jeong, Eun-Jong Kim, Insung Choi, and Min-Keun Song. 2022. "Regulation of Genes Related to Cognition after tDCS in an Intermittent Hypoxic Brain Injury Rat Model" Genes 13, no. 10: 1824. https://doi.org/10.3390/genes13101824

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