N-Acetyl Cysteine (NAC)

 

*Introduction 1,2,3,4

N-acetyl cysteine is derived from the amino acid cysteine. N-acetyl cysteine may help maintain optimal cysteine levels in the body. This is vital since cysteine is considered the rate limiting substrate for the synthesis of glutathione. Another way to say this is that without sufficient cysteine your body cannot make glutathione. Insufficient glutathione is disastrous for your body since glutathione is one of the most formidable natural anti-oxidants and detoxifiers the body produces. Glutathione is on the same level as Vitamin C and Vitamin E in terms of importance. Some special characteristics of glutathione are its ability especially to help protect muscle and joint cells against fat oxidation and foreign toxins.

  *Potential Benefit of N-Acetyl Cysteine for Joint and Muscle Health

 

 *NAC is an anti-oxidant 5,6,7,8,9

Rampant oxidation magnifies and accelerates chronic joint and muscle injury. NAC acts both as an indirect and direct ant-oxidant. NAC acts indirectly by boosting the synthesis of glutathione. As previously mentioned, glutathione is a remarkable endogenous antioxidant that protects muscle and joint tissue from various types a toxins and oxidative stress. Moreover, NAC exhibits direct antioxidant properties with research suggesting that NAC directly neutralizes free radicals.

 *NAC may reduce fatigue 10,11,12,13,14

Fatigue and lack of endurance are frequent complaints of individuals with chronic joint and muscle disease. Investigation implies NAC may directly and indirectly lessen the onset of fatigue and prolong one’s ability to perform intense exercises. While the exact mechanism is unknown, NAC anti-oxidation attributes likely contribute. This underscores the prominent role oxidative stress plays in the onset of fatigue.

 *NAC may prevent muscle damage and soreness 15,16

Muscle loss and lingering local muscle inflammation are common findings in chronic muscular and joint injury. Research suggests NAC may help reduce the oxidative damage induced by inflammation.

 *Safety First 17,18

NAC is generally well tolerated. Some research suggested co-supplementation of high dose Vitamin C and NAC may magnify oxidative stress. However, these findings have yet to be reproduced and may represent an aberration. As with any consideration of any form of supplementation consult your healthcare provide prior to use if you are pregnant, nursing, taking any medications or have any medical conditions. Discontinue use and consult your doctor is any adverse reactions occur.

*These statements have not been evaluated by the Food and Drug Administration. These statements are not intended to diagnose, treat, cure or prevent any disease.

 

 Research

  1. Elgindy EA, El-Huseiny AM, Mostafa MI, Gaballah AM, Ahmed TA. N-acetyl cysteine: could it be an effective ad- juvant therapy in ICSI cycles? A preliminary study. Reprod Biomed Online. 2010; 20(6): 789-796. 

  2. Sen CK: Antioxidant and redox regulation of cellular signaling: introduction. Med Sci Sports Exerc 2001, 33(3):368-370. 

  3. Sen CK: Glutathione homeostasis in response to exercise training and nutritional supplements. Molecular and Cellular 
Biochemistry 1999, 196:31-42. 

  4. Viguie CA, Frei B, Shigenaga MK, et al.: Antioxidant status and indexes of oxidative stress during consecutive days of exercise. J 
Appl Physiol 1993, 75:566-572. 

  5. Sen CK, Packer L: Thiol homeostasis and supplements in physical exercise. Am J Clin Nutr 2000, 72(suppl):653S-669S. 

  6. Viguie CA, Frei B, Shigenaga MK, et al.: Antioxidant status and indexes of oxidative stress during consecutive days of exercise. J 
Appl Physiol 1993, 75:566-572. 

  7. Laires MJ, Madeira F, Sergio J: Preliminary study of the relationship between plasma and erythrocyte magnesium variations and 
some circulating pro-oxidant and antioxidant indices in a standardized physical effort. Magnesium Research 1993, 6:233-238.
  8. Kerksick C, Willoughby D. The Antioxidant role of glu- tathione and N-acetyl cysteine supplements and exercise- induced oxidative stress. J Int Soc Sports Nutr. 2005; 2: 38-44.

  9. Shahin AY, Hassanin IM, Ismail AM, Kruessel JS, Hirch- enhain J. Effect of oral N-acetyl cysteine on recurrent pre- term labor following treatment for bacterial vaginosis. Int J Gynaecol Obstet. 2009; 104(1): 44-48. 

  10. Reid MB, Stokic DS, Koch SM, et al.: N-Acetylcysteine inhibits muscle fatigue in humans. J Clin Invest 1994, 94:2468-2474. 

  11. Supinski GS, Stofan D, Ciufo R, et al.: N-acetylcysteine administration alters the response to inspiratory loading in oxygen- 
supplemented rats. J Appl Physiol 1997, 82(4):1119-1125. 

  12. Matuszczak Y, Farid M, Jones J, et al.: Effect of n-acetylcysteine on glutathione oxidation and fatigue during handgrip exercise. 
Muscle Nerve 2005, 32:633-638. 

  13. Medved I, Brown MJ, Bjorksten AR, et al.: N-acetylcysteine enhances muscle cysteine and glutathione availability and attenuates 
fatigue during prolonged exercise in endurance-trained individuals. J Appl Physiol 2004, 97:1477-1485.
  14. Medved I, Brown MJ, Bjorksten AR, et al.: N-acetylcysteine infusion alters blood redox status but not time to fatigue during 
intense exercise in humans. J Appl Physiol 2003, 94:1572-1582.
  15. Kerksick CM, Kreider RB, Willoughby DS. Intramuscular adaptations to eccentric exercise and antioxidant supplementation. Amino Acids. 2010 Jun;39(1):219-32. doi: 10.1007/s00726-009-0432-7. Epub 2009 Dec 5.
  16. Silva LA1, Silveira PCPinho CATuon TDal Pizzol FPinho RA. N-acetylcysteine supplementation and oxidative damage and inflammatory response aftereccentric exercise. Int J Sport Nutr Exerc Metab. 2008 Aug;18(4):379-88.
  17. Amin AF, Shaaban OM, Bediawy MA. N-acetyl cysteine for treatment of recurrent unexplained pregnancy loss. Reprod Biomed Online. 2008; 17(5): 722-726.
  18.  Childs A, Jacobs C, Kaminski T, et al.: Supplementation with vitamin C and N-Acetyl-Cysteine increases oxidative stress in 
humans after an acute muscle injury induced by eccentric exercise. Free Radical Biology & Medicine 2001, 31(6):745-753.