Effect of Supplemental Oral Curcumin in Patients With Atopic Asthma

Overview

Curcumin has antioxidant properties and in animal models has numerous molecular targets, many of which are intracellular, such as transcription factors AP-1 and NF. As such, it inhibits the secretion of both pro-inflammatory (TNF-, IL-6) and anti-inflammatory (IL-10) cytokines, possibly by inhibiting transcription factors such as nuclear factor-B (NF-B) and activator protein-1 (AP-1) (Wong et al).

Research Design This is a randomized, double-blinded, placebo-controlled pilot study to evaluate the effects of oral supplementation of curcumin 2000mg, versus placebo, on patients with a history of stable persistent asthma and allergic sensitization. Ng et al investigated mini-mental status exam (MMSE) scores in 1010 patients without dementia who reported ingesting varying quantities of curry. The authors found a statistically significant improvement in MMSE among patients who reported consuming curry "occasionally", "often, or "very often" (Ng et al). Curcumin is theorized to aid patients with dementia by improving innate immunity and by acting as an anti-inflammatory, antioxidant agent. In a double-blind, placebo-controlled trial of 34 elderly patients with Alzheimer's disease, patients were randomized to receive 0, 1, or 4 grams PO curcumin. While the study did not show significant slowing in cognitive decline over a 6 month period, the dosages were tolerated up to 4 grams without significant adverse effects (Baum et al). Wong et al demonstrated an inhibitory effect of curcumin on cytokines produced by human cells stimulated by the addition of Dermatophagoides pteronynssinus (Der p1), the major allergen derived from this dust mite. The authors investigated the cytokine changes that occur in bronchial epithelial cells and eosinophils upon activation by Der p1 (increased IL-10, TNF-, IL-6, GM-CSF, and IL-1). Curcumin inhibited such activation. For example, the addition of curcumin decreased the production of IL-10 in Der p1-activated human epithelial/eosinophil co-culture cell lines. Additionally, the addition of curcumin to Der p1-activated eosinophil cell cultures decreased the release of IL-10, TNF-, and IL-1. of NF-B and AP-1 induced by addition of Der p1 in the control group. The authors theorized this occurred via inhibition of AP-1 (Wong et al). Several additional studies highlight the effect of curcumin in vitro. Curcumin decreases the expression and release of eotaxin, MCP-1, and MCP-3 from IL-1-stimulated human airway smooth muscle cells (Wuyts et al). Additionally, curcumin added to Der f-stimulated lymphocyte cell cultures from allergic asthmatics inhibits Der f-induced lymphocyte proliferation and production of IL-2, IL-4, IL-5, and GM-CSF (Kobayashi et al). Ram et al sensitized guinea pigs with ovalbumin to establish airway hyperresponsiveness. There was a significant decrease in airway constriction and hyperreactivity when curcumin (20mg/kg) was added during the sensitization phase. There are no clinical studies which have evaluated the effect of oral curcumin supplementation on asthma severity in allergic asthmatics or any in vivo studies in humans with asthma. Therefore, this is a pilot study to evaluate the effects of oral supplementation with curcumin on patients with persistent atopic asthma.

Conditions

Interventions

Eligibility

Locations (1)

Outcomes