Piperine
Piperine is an active phenol of the black pepper plant Piper nigrus. It is perhaps most famous for its ability to significantly improve the bioavailability of the turmeric compound curcumin1,2. However, it appears to have its own useful properties against MS, as seen in animal models of the disease.
In EAE rats, piperine at a dose of 5 mg/kg was observed to decrease the level of pro-inflammatory cytokines (TNF-alpha, IL-1β) and enhance anti-inflammatory cytokines (IL-10, Nrf2, HO-1, and MBP). Supplementation also increased total antioxidant capacity and reduced a key oxidative stress marker (malondialdehyde) in the CNS, and was found to have anti-apoptotic and neuroprotective effects3. In EAE mice, piperine exhibited a strong preventive and therapeutic effect by restricting inflammatory cell entrance into the CNS and preventing myelin destruction and blood-brain barrier disruption4.
In mice with demyelination, piperine at doses of 5-20 mg/kg improved both memory performance and myelin repair. Piperine also inhibited inflammatory markers and enhanced anti-inflammatory markers in brain tissue5.
In a cell model of pregnancy, black pepper essential oil – a concentrated source of piperine, 2-7 mg/100 g of black pepper itself – was suggested to reduce cell survival at concentrations higher than 0.005%6. In an earlier study, piperine at a dose of more than 5 mg/kg/day was found to have an anti-fertility or pregnancy-disrupting effect7. Though this dose exceeds that recommended for use in MS or to enhance curcumin bioavailability, caution should still be taken.
References
1.Bisht S, Maitra A. Systemic delivery of curcumin: 21st century solutions for an ancient conundrum. Curr Drug Discov Technol. Sep 2009;6(3):192-9. doi:10.2174/157016309789054933
2.Anand P, Thomas SG, Kunnumakkara AB, et al. Biological activities of curcumin and its analogues (Congeners) made by man and Mother Nature. Biochem Pharmacol. Dec 1 2008;76(11):1590-611. doi:10.1016/j.bcp.2008.08.008
3.Nasrnezhad R, Halalkhor S, Sadeghi F, Pourabdolhossein F. Piperine Improves Experimental Autoimmune Encephalomyelitis (EAE) in Lewis Rats Through its Neuroprotective, Anti-inflammatory, and Antioxidant Effects. Mol Neurobiol. Nov 2021;58(11):5473-5493. doi:10.1007/s12035-021-02497-5
4.Liu Z, Hu Q, Wang W, et al. Natural product piperine alleviates experimental allergic encephalomyelitis in mice by targeting dihydroorotate dehydrogenase. Biochem Pharmacol. Jul 2020;177:114000. doi:10.1016/j.bcp.2020.114000
5.Roshanbakhsh H, Elahdadi Salmani M, Dehghan S, Nazari A, Javan M, Pourabdolhossein F. Piperine ameliorated memory impairment and myelin damage in lysolecethin induced hippocampal demyelination. Life Sci. Jul 15 2020;253:117671. doi:10.1016/j.lfs.2020.117671
6.Yancu D, Sanderson T. Essential oils disrupt steroidogenesis in a feto-placental co-culture model. Reprod Toxicol. Dec 2019;90:33-43. doi:10.1016/j.reprotox.2019.08.010
7.Piyachaturawat P, Glinsukon T, Peugvicha P. Postcoital antifertility effect of piperine. Contraception. Dec 1982;26(6):625-33. doi:10.1016/0010-7824(82)90137-8