Bacterial melanin crosses the blood–brain barrier in rat experimental model

Fluids and Barriers of the CNS

Anichka Hovsepyan²  Tigran Petrosyan¹ 

[1] Armenian State Institute of Physical Education, 11 Alex Manukian, Yerevan 0028, Armenia;SPC “Armbiotechnology” NAS RA, 14 Gyurjyan Str., Yerevan, Armenia

关键词: Labeling;    Transport;    Blood–brain-barrier;    Bacterial melanin;   

Others  :  1098256
DOI  :  10.1186/2045-8118-11-20

 received in 2014-05-06, accepted in 2014-08-19,  发布年份 2014

【 摘 要 】

Background

Bacterial melanin has been proven to stimulate regeneration after CNS lesions. The purpose of this study was to test, whether bacterial melanin can enter the brain via the blood–brain barrier (BBB).

Methods

Bacterial melanin (BM) was radioactively labeled by the iodobead method and used to test the BBB permeability after systemic injection into rats. The unidirectional influx rate from the blood was calculated by multiple-time regression analysis. A subgroup of the animals was co-injected with non-labeled BM to determine if BM has a saturable transport across the BBB. The levels of radioactivity were determined in the serum and tissues. Arterial blood was sampled to obtain the level of I-BM at different time points after injection. After systemic perfusion with saline, animals were decapitated and brain, spinal cord, liver and kidney samples were obtained and homogenized to test the I-BM level.

Results

Study results showed that radioactively-labeled bacterial melanin crossed the BBB, was enzymatically stable in blood and in brain parenchyma. Entry to brain was reduced when non-labeled BM was also present. Circulating melanin entered all regions of the CNS but the uptake was higher in lumbar spinal cord, thalamus, hypothalamus and substantia nigra. Liver and kidneys had high uptake rates of BM.

Conclusions

These results show that bacterial melanin has saturable transport across the BBB and selectively targets some CNS regions. Such transport may contribute to the neuroprotective action of bacterial melanin.

【 授权许可】

   
2014 Petrosyan and Hovsepyan; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

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