Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Dec 22;14(1):12.
doi: 10.3390/brainsci14010012.

Vanillic Acid Ameliorates Demyelination in a Cuprizone-Induced Multiple Sclerosis Rat Model: Possible Underlying Mechanisms

Sally M Safwat  1 , Mahmoud El Tohamy  1 , Moutasem Salih Aboonq  2 , Amaal Alrehaili  2 , Ahmad A Assinnari  2 , Abdulrahman S Bahashwan  2 , Ahmed A ElGendy  1   2 , Abdelaziz M Hussein  1
Affiliations

Vanillic Acid Ameliorates Demyelination in a Cuprizone-Induced Multiple Sclerosis Rat Model: Possible Underlying Mechanisms

Sally M Safwat et al. Brain Sci. .

Abstract

Objective: To investigate the effect of vanillic acid (VA) on a Cuprizone (Cup) demyelinating rat model and the mechanisms behind such effect.

Methods: Thirty adult male Sprague Dawley (SD) rats were randomly divided into three groups: control, Cuprizone, and VA groups. Cuprizone was administrated at a dose of 450 mg/kg per day orally via gastric gavage for 5 weeks. The nerve conduction velocity (NCV) was studied in an isolated sciatic nerve, and then the sciatic nerve was isolated for histopathological examination, electron microscope examination, immunohistochemical staining, and biochemical and PCR assay. The level of IL17 was detected using ELISA, while the antioxidant genes Nrf2, HO-1 expression at the level of mRNA, expression of the myelin basic protein (MBP), interferon-gamma factor (INF)-γ and tumor necrosis factor (TNF)-α, and apoptotic marker (caspase-3) were measured using immunohistochemistry in the sciatic nerve.

Results: There was a significant reduction in NCV in Cup compared to normal rats (p < 0.001), which was markedly improved in the VA group (p < 0.001). EM and histopathological examination revealed significant demyelination and deterioration of the sciatic nerve fibers with significant improvement in the VA group. The level of IL17 as well as the expression of INF-γ and caspase-3 were significantly increased with a significant reduction in the expression of MBP, Nrf2, and HO-1 in the sciatic nerve (p < 0.01), and VA treatment significantly improved the studied parameters (p < 0.01).

Conclusion: The current study demonstrated a neuroprotective effect for VA against the Cup-induced demyelinating rat model. This effect might be precipitated by the inhibition of inflammation, oxidative stress, and apoptosis.

Keywords: Nrf2; cuprizone; demyelinating; neuroinflammation; vanillic acid.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Nerve conduction study in isolated sciatic nerve. (A) nerve conduction velocity (m/s) from different groups. Traces of NCS records from the control group (B), Cuprizone group (C), and VA group (D). * significant vs. control group, # significant vs. Cuprizone group. CAP = compound nerve action potential. p < 0.05. Red line is the curve of M wave and blue line indicate the stimulus.
Figure 2
Figure 2
The concentration of IL17 (pg/mL) (A) and the expression of antioxidant genes (Nrf2, (B) and HO-1, (C)) in the sciatic nerve in different groups. * Significant vs. control group, # significant vs. Cuprizone group. p < 0.05.
Figure 3
Figure 3
Luxol fast blue (LFB) staining for myelination of the sciatic nerve. (A) the score of demyelinating areas in different studied groups. Photomicrographs of LFB staining from the control group.(B), Cuprizone group (C), and VA group (D). Red arrows indicate the areas of demyelination. * Significant vs. control group, # significant vs. Cuprizone group. p < 0.05.
Figure 4
Figure 4
Immunohistopathological staining for myelin basic protein (MBP) in sciatic nerve. (A) the score of MBP expression in different studied groups. Photomicrographs of MBP staining from control group.(B), Cuprizone group (C), and VA group (D). Red arrows indicate brown staining for myelin basic protein (MBP) * significant vs. control group, # significant vs. Cuprizone group. p < 0.05.
Figure 5
Figure 5
Immunohistopathological staining for caspase-3 in sciatic nerve. (A) the score of caspase-3 expression in different studied groups. Photomicrographs of caspase-3 from the control group.(B), Cuprizone group (C), and VA group (D). * Significant vs. control group, # significant vs. Cuprizone group. p < 0.05.
Figure 6
Figure 6
Immunohistopathological staining for INF-γ in sciatic nerve. (A) the score of INF-γ expression in different studied groups. Photomicrographs of INF-γ from the control group. (B), Cuprizone group (C), and VA group (D). red arrows indicate brown staining for INF-γ * significant vs. control group, # significant vs. Cuprizone group. * p < 0.05.
Figure 7
Figure 7
Immunohistopathological staining for TNF-α in sciatic nerve. (A) the score of TNF-α expression in different studied groups. Photomicrographs of TNF-α from the control group (B), Cuprizone group (C), and VA group (D).
Figure 8
Figure 8
Histopathological examination of the sciatic nerve using H&E from different studied groups. (A) photomicrograph from the normal control group showing dense, uniform, regular myelinated nerve fibers arranged in concentric layers with a regular arrangement of Schwann cell nuclei (white arrows). (B) = photomicrograph from the Cuprizone group showing that myelinated fibers are broad, loose, and partially demyelinated (red arrows) with an irregular pattern of clear vacuoles, i.e., bubbling (blue arrows) and (C) = photomicrograph from vanillic acid-treated group revealed regular myelin sheaths (white arrows).
Figure 9
Figure 9
Ultra-microscopic structure of the sciatic nerve via electron microscopy for different studied groups. (A) = score of myelin sheaths’ thickness in micrometers in different groups. (B) = photomicrograph from normal control group of rats showing large myelinated nerve fibers with thick myelin sheath (M) and its axonal (A) cytoplasm containing mitochondria (m) with small-diameter nerve fiber axons surrounded by Schwann cells ensheathing each axon in a pocket of its cytoplasm, forming a Remak bundle (red circle). (C) = photomicrograph from the Cuprizone group showing endoneurial edema (manifested by the distinct displacement between nerve fibers), Wallerian degeneration (W) in axons of large-diameter fibers and degeneration of non-myelinated nerve fibers surrounded by Schwan cells. (D) = photomicrograph from vanillic acid-treated group showing intact large- and small-diameter axons near the normal control group. * significant vs. control group, # significant vs. Cuprizone group. p < 0.05.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Ohl K., Tenbrock K., Kipp M. Oxidative stress in multiple sclerosis: Central and peripheral mode of action. Exp. Neurol. 2016;277:58–67. doi: 10.1016/j.expneurol.2015.11.010. - DOI - PMC - PubMed
    1. Abdel-maged A.E., Gad A.M., Rashed I.A., Azab S.S., Mohamed E.A., Awad A.S. Repurposing of secukinumab as neuroprotective in cuprizone-induced multiple sclerosis experimental model via inhibition of oxidative, inflammatory, and neurodegenerative signaling. Mol. Neurobiol. 2020;57:3291–3306. doi: 10.1007/s12035-020-01972-9. - DOI - PubMed
    1. Stadelmann C., Wegner C., Brück W. Inflammation, demyelination, and degeneration—Recent insights from MS pathology. Biochim. Biophys. Acta (BBA)-Mol. Basis Dis. 2011;1812:275–282. doi: 10.1016/j.bbadis.2010.07.007. - DOI - PubMed
    1. Lassmann H., Bradl M. Multiple sclerosis: Experimental models and reality. Acta Neuropathol. 2017;133:223–244. doi: 10.1007/s00401-016-1631-4. - DOI - PMC - PubMed
    1. Begum Z., Vijayalakshmi S., Raghunath G. Cuprizone Induced Demyelination in Male Wistar Rats with Timeline Changes Admistered through Oral Gavage. Ann. Rom. Soc. Cell Biol. 2021;25:12643–12653.