Suppression of Mycobacterium tuberculosis induced reactive oxygen species (ROS) and TNF‐α mRNA expression in human monocytes by allicin

Abstract

Chronic inflammation associated with tumor necrosis factor (TNF)-a and reactive oxygen species (ROS) is the hallmark of tuberculosis. Mycobacterium tuberculosis (MTB) directly stimulates human monocytes to secrete TNF-a. We show the augmented expression of TNF-a mRNA in MTB-infected monocytes by cellular activation and ROS was suppressed by allicin in a dose-dependent manner. Also, allicin enhanced the glutathione peroxidase activity, which correlated inversely with the downregulation of ROS and TNF-a in MTB-infected monocytes. Hence, allicin may prove to be a valuable natural antioxidant in combating tuberculosis.

Modulation of cyclophosphamide-induced early lung injury by allicin

“…Rats treated concurrently with allicin showed a minimal degree of lung damage, no areas of intralobular necrosis or significant inflammatory infiltration in lung, thickening of the alveolar septa in 35% of all examined field. Allicin could act directly on the cell membranes either endothelial or epithelial membranes and regulate the expression of cytokines (Hasan et al, 2006).…”

Allicin from garlic suppresses TNF-α and augments IFN-γ expressions in monocyte cultures from patients with Vaginitis

“…9 We have recently demonstrated the anti-inflammatory effects of allicin on autocrine cytokine TNF-in α MTB-infected monocytes. 7 Thus, it seems that the anti-infective activity exerted by allicin in vaginal infections is probably by suppressing TNF-transcription, which is evident from the pattern, by α which allicin inhibits the secretion of soluble TNF-in infected monocyte cultures in a α dose-dependent manner. Thus, in view of our earlier results in other systems showing effective inhibitory effects of allicin as well as based on the data of the present study, the idea of using 2-3 crushed garlic cloves spread on a swab and inserted inside the vagina for 2-3 times a day in order to combat vaginal infections cannot be ruled out.…”

“…The amount of secreted TNF-and α IFN-γ proteins in various culture supernatants was determined as described by us earlier 7,8 by use of a commercial ELISA Kit (R & D systems), according to the manufacturer's specifications. The cut off or lower limit of sensitivity was 4.4 pg/ml.…”

“…In view of our promising results in other systems where allicin was beneficial in the containment of mycobacterium tuberculosis infection in human monocytes, 7,8 we probed the utilization of allicin from garlic in down-regulating augmented levels of TNF-α and GSH in cultures of monocytes from patients having vaginal infections, which in turn may help in understanding the use of allicin as an adjunct in vaginal infection therapy.…”

“…[4][5][6] Focus has now shifted in probing new natural compounds having antioxidant, antibacterial, antifungal and antiviral properties that may help in the treatment of vaginal infections. Allicin, a natural antioxidant from garlic, 7,8 is one such natural compound that may probably help in combating vaginal infections. The uses of garlic in combating bacterial and fungal infections are well known since ancient times in alternative medicine.…”