Parkinsons Dis. 2017;2017:6025358. doi: 10.1155/2017/6025358.

Identification of NURR1 (Exon 4) and FOXA1 (Exon 3) Haplotypes Associated with mRNA Expression Levels in Peripheral Blood Lymphocytes of Parkinson’s Patients in Small Indian Population

Jayakrishna Tippabathani, Jayshree Nellore, Vaishnavie Radhakrishnan, Somashree Banik, Sonia Kapoor

From the Department of Biotechnology, Sathyabama University, Chennai 600119, India

Correspondence should be addressed to Jayshree Nellore, Department of Biotechnology, Sathyabama University, Chennai 600119, India, E.mail: sree_nellore@yahoo.com

 

Abstract

Here, we study the expression of NURR1 and FOXA1 mRNA in peripheral blood lymphocytes and its haplotypes in coding region in a small Chennai population of India. Thirty cases of Parkinson’s patients (PD) with anti-PD medications (20 males aged and 10 females aged) and 30 age matched healthy people (20 males aged and 10 females aged) were included. The expression of NURR1 and FOXA1 in PBL was detected by Q-PCR and haplotypes were identified by PCR-SSCP. In the 30 PD cases examined, NURR1 and FOXA1 expression was significantly reduced in both male and female PD patients. However, NURR1 (57.631% reduced in males; 28.93% in females) and FOXA1 (64.42% in males; 55.76% in females) mRNA expression did differ greatly between male and female PD patients. Polymorphisms were identified at exon 4 of the NURR1 and at exon 3 of the FOXA1, respectively, in both male and female patients. A near significant difference in SSCP patterns between genders of control and PD population was analyzed suggesting that further investigations of more patients, more molecular markers, and coding regions should be performed. Such studies could potentially reveal peripheral molecular marker of early PD and different significance to the respective genders.

https://doi.org/10.1155/2017/6025358

 

Supplement:

The dopaminergic neurons in the midbrain region of central nervous system project an extensive network of connection throughout the forebrain, including neocortex. The midbrain-forebrain dopaminergic circuits are thought to regulate a diverse set of behaviours from the control of movement to modulation of cognition and desire because they relate to mood, attention, reward and addiction. Defects in these pathways, including neurodegeneration are implicated in variety of psychiatric and neurological diseases such as Schizophrenia, attention-deficit/hyperactivity disorder, drug addiction and Parkinson’s Disease. Since mesencephalic dopaminergic neurons are associate to one of the most prominent human neurodegenerative ailment, Parkinson’s Disease, the molecular mechanisms underlying their development and adult cellular properties has been the subject of intensive investigation.

 

Throughout life, a number of transcription factors including Foxa1, Foxa2, Nurr1, Pitx3, Otx2, Lmx1a, Lmx1b, En1, and En2 determine the fate of dopaminergic neuronal population and control essential processes such as localisation in ventral midbrain, their neurotransmitter phenotype, their target innervation and synapse formation. Studies of transcription factors have not only revealed importance of these genes during development but also roles in the long term survival and maintenance of these neurons. Disruption of post mitotic neuron maintenance through an alteration of their transcriptional/translational regulation may lead to neurodegeneration.

 

Numerous studies have used Peripheral Blood Lymphocytes (PBL) to measure specific changes in dopamine (DA) content, tyrosine hydroxylase activity, DA receptors, and DA transporters in patients with PD [1]. In addition, a significant decrease in mitochondrial complex I activity and a significant increase in caspase-3 activity have been reported in PBL of PD patients [2]. Likewise, genome-wide expression in PBL of PD patients and healthy controls identified co-chaperone protein ST13 as a potential molecular marker of early PD [3]. Based on these data, it has been proposed that PBL can be used for detecting the possible indicators of pathological mechanisms occurring in the brains of patients with PD.

 

Magnetic resonance imaging (MRI) and computed tomography (CT) scan are usually unremarkable or may show age specific changes in Parkinson’s disease. There is no lab test for PD, so it can be difficult to diagnose. Doctors use medical history and a neurological examination to diagnose it, but 70% of nigral neurons are lost when symptoms appear. Late diagnosis hampers clinical development of new disease-modifying therapies; only alleviating symptoms is possible at present. For this reason, great interest in developing peripheral biomarker for PD has increased. Gene expression profile in peripheral blood lymphocytes (PBL) is done in an attempt to identify potential peripheral biomarkers of the disease. Our recent publication addresses this issue for the expression of NURR1 and FOXA1 mRNA in peripheral blood lymphocytes and its haplotypes in coding region in a small Chennai population of India [4].

 

Recent studies indicated decreased expression in PBL in PD patients independent of medication, disease duration, or severity; NURR1 could be a useful biomarker for PD and related disorders. In the 30 PD cases examined in our study, NURR1 and FOXA1 expression was significantly reduced in both male and female PD patients. However, NURR1 (57.631% reduced in males; 28.93% in females) and FOXA1 (64.42% in males; 55.76% in females) mRNA expression did differ greatly between male and female PD patients [4].

 

It is postulated that variants in NURR1 gene cause decrease in NURR1 mRNA and affect the transcription of gene that encodes TH that could cause dysfunction of dopaminergic neurons and lead to PD. Various studies have reported coding missense mutation in exon 3 of NURR1 (709C>G and 711 C/A), −291Tdel and −245T→G sequence variation in the noncoding exon-1 within the 5’ untranslated region, and mutations in exon 2 at 388 G/A, 35 A/G, and 21 C/G respectively, including some intron regions which markedly attenuates NURR1-induced transcriptional activation, leading to decreased expression being identified in a patient with PD [5]. However, there is no evidence of the genetic variations in FOXA1 gene in PD patients. Our study clearly identified polymorphisms at exon 4 of the NURR1 and at exon 3 of the FOXA1, respectively, in both male and female patients (Figure 1 and 2). A near significant difference in SSCP patterns between genders of control and PD population was analysed. These findings endorse the fact that haplotype variation in transcription factors might have clinically important and clinically relevant association with PD and also more broadly with potential applications in risk stratification, prognostication, and the development of appropriately targeted-treatment strategies

 

 

Figure 1. Representative SSCP analyses for exon 4 of the NURR1 gene in male and female PD patients. The exon was divided into two reactions: 1 and 2. A, B, D represents conformational patterns of the bands found. Two band patterns were identified for the exon 4 of NURR1 gene in male PD controls: Pattern A and B. Male PD patients exhibited migration pattern D (pattern suggesting alterations) with respect to the reaction 1 and migration pattern B (similar to control) with respect to reaction 2 of the exon 4 of NURR1 gene. The entire female PD controls revealed pattern B with respect to the two reactions of the exon 4 of NURR1 gene, which suggested alteration in the pattern of migration, compared to male controls. Interestingly, all the twenty female PD patients exhibited migration pattern B (similar to controls) with respect to the two reactions of the exon 4 of NURR1 gene, as reported in Parkinson’s disease, Volume 2017 (2017).

 

 

Figure 2. Representative SSCP analyses for exon 3 of the FOXA1 gene in male and female PD patients. The exon was divided into two reactions: 1 and 2. A, B, C, D represents conformational patterns of the bands found. Two band patterns were identified for the exon 3 of FOXA1 gene in male PD controls: Pattern C with respect to reaction 1 and B with respect to reaction 2. While, male PD patients exhibited migration pattern B (pattern suggesting alterations) with respect to the reaction 1 and pattern A (pattern suggesting alterations) with respect to the reaction 2 of the exon 3 of FOXA1 gene. However, for female PD controls a single band pattern was revealed: Pattern D with respect to the two reactions of the exon 3 of FOXA1 gene, which suggested alteration in the pattern of migration, compared to male controls. Interestingly, all the twenty female PD patients exhibited migration pattern B (similar to controls) with respect to the two reactions of the exon 3 of FOXA1 gene, as reported in Parkinson’s disease, Volume 2017 (2017).

 

 

References 

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2. Blandini, F., A. Mangiagalli, M. Cosentino, F. Marino, A. Samuele, E. Rasini, R. Fancellu et al. “Peripheral Markers of Apoptosis in Parkinson’s Disease,” Annals of the New York Academy of Sciences, vol. 1010, no. 1, pp. 675-678, 2003.
3. Scherzer, Clemens R., Aron C. Eklund, Lee J. Morse, Zhixiang Liao, Joseph J. Locascio, Daniel Fefer, Michael A. Schwarzschild, MG. Schlossmacher, MA. Hauser, MA. Vance, LR. Sudarsky. “Molecular markers of early Parkinson’s disease based on gene expression in blood,” Proceedings of the National Academy of Sciences, vol. 104, no. 3, pp. 955-960. 2007
4. Jayakrishna Tippabathani, Jayshree Nellore, Vaishnavie Radhakrishnan, Somashree Banik, Sonia Kapoor.Identification of NURR1 (Exon 4) and FOXA1 (Exon 3) Haplotypes Associated with mRNA Expression Levels in Peripheral Blood Lymphocytes of Parkinson’s Patients in Small Indian Population, Parkinson’s disease, Volume 2017 (2017), Article ID 6025358, 8 pages
5. Le, Wei-dong, Pingyi Xu, Joseph Jankovic, Hong Jiang, Stanley H. Appel, Roy G. Smith, and Demetrios K. Vassilatis. “Mutations in NR4A2 associated with familial Parkinson disease,” Nature genetics, vol. 33, no. 1, pp. 85-89, 2003