N-acetyl-L-Cysteine amide (Synonyms: N-Acetylcysteine amide, NACA)

N-acetyl-L-Cysteine amide (NACA) is a novel antioxidant, the amide form of N-acetylcysteine (NAC), due to its permeability through both cellular and mitochondrial membranes ^[1]. N-acetylcysteine amide permeates cellular and mitochondrial membranes, crosses the blood-brain barrier [1,2] and has higher radical scavenging ability, metal chelating activity and reducing power than NAC [3].

N-acetyl-L-Cysteine amide protects neurons and dopaminergic cells from oxidative stress in tissue cultures and lipid peroxidation in neuronal cell lines [4,5]. N-acetyl-L-Cysteine amide (750 µM) protected the PC12 cells from glutamate toxicity by slightly decreasing the bleb formation on neurites, and increased the PC12 cell GSH level [5]. N-acetyl-L-Cysteine amide protected PC12 cells against glutamate cytotoxicity by decreasing the glutamate-induced ROS accumulation [5]. N-acetylcysteine amide (1 mM) prevents METH-induced oxidative stress in human brain microvascular endothelial (HBMVEC) cells [6].

In moderate TBI, N-acetyl-L-Cysteine amide treatment improves mitochondrial bioenergetics, cognitive function, cortical tissue sparing and reduces lipid peroxidation product 4-hydroxynonenal compared to NAC or vehicle treated rats [7]. In acute spinal cord injury, N-acetyl-L-Cysteine amide (150 or 300 mg/kg/day) treatment improves mitochondrial bioenergetics, maintains mitochondrial glutathione and improves tissue sparing and hind limb function [8].

References:
[1]. Grinberg L, Fibach E, Amer J, et al. N-acetylcysteine amide, a novel cell-permeating thiol, restores cellular glutathione and protects human red blood cells from oxidative stress[J]. Free Radical Biology and Medicine, 2005, 38(1): 136-145.
[2]. Offen D, Gilgun‐Sherki Y, Barhum Y, et al. A low molecular weight copper chelator crosses the blood-brain barrier and attenuates experimental autoimmune encephalomyelitis[J]. Journal of neurochemistry, 2004, 89(5): 1241-1251.
[3]. Ates B, Abraham L, Ercal N. Antioxidant and free radical scavenging properties of N-acetylcysteine amide (NACA) and comparison with N-acetylcysteine (NAC)[J]. Free radical research, 2008, 42(4): 372-377.
[4]. Bahat‐Stroomza M, Gilgun‐Sherki Y, Offen D, et al. A novel thiol antioxidant that crosses the blood brain barrier protects dopaminergic neurons in experimental models of Parkinson's disease[J]. European Journal of Neuroscience, 2005, 21(3): 637-646.
[5]. Penugonda S, Mare S, Goldstein G, et al. Effects of N-acetylcysteine amide (NACA), a novel thiol antioxidant against glutamate-induced cytotoxicity in neuronal cell line PC12[J]. Brain research, 2005, 1056(2): 132-138.
[6]. Zhang X, Banerjee A, Banks W A, et al. N-Acetylcysteine amide protects against methamphetamine-induced oxidative stress and neurotoxicity in immortalized human brain endothelial cells[J]. Brain research, 2009, 1275: 87-95.
[7]. Pandya J D, Readnower R D, Patel S P, et al. N-acetylcysteine amide confers neuroprotection, improves bioenergetics and behavioral outcome following TBI[J]. Experimental neurology, 2014, 257: 106-113.
[8]. Patel S P, Sullivan P G, Pandya J D, et al. N-acetylcysteine amide preserves mitochondrial bioenergetics and improves functional recovery following spinal trauma[J]. Experimental neurology, 2014, 257: 95-105.