PMID- 34445097 OWN - NLM STAT- MEDLINE DCOM- 20210920 LR - 20210920 IS - 1422-0067 (Electronic) IS - 1422-0067 (Linking) VI - 22 IP - 16 DP - 2021 Aug 4 TI - Reviewing the Significance of Blood-Brain Barrier Disruption in Multiple Sclerosis Pathology and Treatment. LID - 10.3390/ijms22168370 [doi] LID - 8370 AB - The disruption of blood-brain barrier (BBB) for multiple sclerosis (MS) pathogenesis has a double effect: early on during the onset of the immune attack and later for the CNS self-sustained 'inside-out' demyelination and neurodegeneration processes. This review presents the characteristics of BBB malfunction in MS but mostly highlights current developments regarding the impairment of the neurovascular unit (NVU) and the metabolic and mitochondrial dysfunctions of the BBB's endothelial cells. The hypoxic hypothesis is largely studied and agreed upon recently in the pathologic processes in MS. Hypoxia in MS might be produced per se by the NVU malfunction or secondary to mitochondria dysfunction. We present three different but related terms that denominate the ongoing neurodegenerative process in progressive forms of MS that are indirectly related to BBB disruption: progression independent of relapses, no evidence of disease activity and smoldering demyelination or silent progression. Dimethyl fumarate (DMF), modulators of S1P receptor, cladribine and laquinimode are DMTs that are able to cross the BBB and exhibit beneficial direct effects in the CNS with very different mechanisms of action, providing hope that a combined therapy might be effective in treating MS. Detailed mechanisms of action of these DMTs are described and also illustrated in dedicated images. With increasing knowledge about the involvement of BBB in MS pathology, BBB might become a therapeutic target in MS not only to make it impenetrable against activated immune cells but also to allow molecules that have a neuroprotective effect in reaching the cell target inside the CNS. FAU - Balasa, Rodica AU - Balasa R AD - Department of Neurology, University of Medicine, Pharmacy, Sciences and Technology "George Emil Palade", 540136 Targu Mures, Romania. AD - Neurology 1 Clinic, Emergency Clinical County Hospital Mures, 540136 Targu Mures, Romania. FAU - Barcutean, Laura AU - Barcutean L AUID- ORCID: 0000-0002-3033-0583 AD - Department of Neurology, University of Medicine, Pharmacy, Sciences and Technology "George Emil Palade", 540136 Targu Mures, Romania. AD - Neurology 1 Clinic, Emergency Clinical County Hospital Mures, 540136 Targu Mures, Romania. FAU - Mosora, Oana AU - Mosora O AD - Neurology 1 Clinic, Emergency Clinical County Hospital Mures, 540136 Targu Mures, Romania. FAU - Manu, Doina AU - Manu D AUID- ORCID: 0000-0001-8374-4977 AD - Advanced Research Center Medical and Pharmaceutical, University of Medicine, Pharmacy, Sciences and Technology "George Emil Palade", 540142 Targu Mures, Romania. LA - eng GR - 10126/2/17.12.2020/Universitatea de Medicina, Farmacie, Stiinte si Tehnologie din Targu Mures/ PT - Journal Article PT - Review DEP - 20210804 PL - Switzerland TA - Int J Mol Sci JT - International journal of molecular sciences JID - 101092791 SB - IM MH - Animals MH - Blood-Brain Barrier/drug effects/metabolism/*pathology MH - Disease Progression MH - Endothelial Cells/drug effects/metabolism/pathology MH - Humans MH - Mitochondria/drug effects/metabolism/pathology MH - Multiple Sclerosis/drug therapy/metabolism/*pathology PMC - PMC8395058 OTO - NOTNLM OT - blood-brain barrier OT - disease modifying therapies progression OT - impermeability OT - multiple sclerosis COIS- The authors declare no conflict of interest. EDAT- 2021/08/28 06:00 MHDA- 2021/09/21 06:00 PMCR- 2021/08/04 CRDT- 2021/08/27 01:22 PHST- 2021/06/02 00:00 [received] PHST- 2021/07/19 00:00 [revised] PHST- 2021/07/31 00:00 [accepted] PHST- 2021/08/27 01:22 [entrez] PHST- 2021/08/28 06:00 [pubmed] PHST- 2021/09/21 06:00 [medline] PHST- 2021/08/04 00:00 [pmc-release] AID - ijms22168370 [pii] AID - ijms-22-08370 [pii] AID - 10.3390/ijms22168370 [doi] PST - epublish SO - Int J Mol Sci. 2021 Aug 4;22(16):8370. doi: 10.3390/ijms22168370.