Intestinal inflammatory profile shows increase in a diversity of biomarkers in irritable bowel syndrome

Figures & data

Table 1. Demographic and baseline variables for patients included.

	IBS-All N = 42	IBS-FT n = 6	IBS-FI n = 8	Controls N = 20	p Value
Age (median [range])	48.5	50 [40, 72]	48 [25, 62]	59 [35, 79]	Ns
Female percent	68%	63%	100%	35%	.019^#
Abdominal pain/discomfort (mm)	55.2	61	50	0	Ns*
Bloating (mm)	56	63	51	0	Ns*
Stool frequency (median [range])	1.8	1.6	1.7	1.0	Ns*
Boston scale stool consistency (mean [range])	4.6	5.2	3.9	4.0	Ns*

FI: fructose intolerance; FT: fructose tolerance; IBS: irritable bowel syndrome.

^# Controls vs. IBS groups.

* IBS subgroups compared.

Table 2. Mucosal levels of cytokines, chemokines and growth factors in patients with IBS and in healthy controls.

Mediator	IBS (N = 42)	Normal control (N = 20)	p Value
IFNγ	18 (16–20)	14 (12–17)	.010
IL-1β	6.7 (5.6–7.9)	4.1 (3.1–5.5)	.004
IL-1RA	1299 (1012–1668)	818 (533–1254)	.057
IL-2	0.64 (0.58–0.71)	0.39 (0.35–0.44)	<.0005
IL-4	0.91 (0.79–1.04)	0.71 (0.62–0.82)	.032
IL-5†	0.29 (0.25–0.33)	0.33 (0.22–0.43)	.435
IL-6	1.5 (1.1–2.0)	1.1 (0.9–1.2)	.136
IL-7	10.7 (9.7–11.9)	10.6 (9.2–12.2)	.893
IL-8	24 (16–35)	15 (11–19)	.101
IL-9	8.2 (7.2–9.2)	6.5 (5.7–7.5)	.040
IL-10	5.5 (4.7–6.4)	4.6 (3.8–5.5)	.165
IL-12p70	5.8 (4.9–6.9)	5.2 (4.5–6.1)	.404
IL-13	0.85 (0.79–0.91)	0.81 (0.73–0.90)	.448
IL-15	2.3 (2.1–2.6)	1.7 (1.5–1.8)	<.0005
IL-17†	3.2 (2.6–3.7)	2.0 (1.6–2.4)	.001*
TNF	160 (143–178)	130 (115–147)	.025
Eotaxin	6.7 (5.6–7.9)	4.1 (3.1–5.5)	.004
IP-10	590 (437–798)	401 (301–533)	.119
MCP1MCA	75 (66–86)	71 (60–85)	.647
MIP-1α	3.3 (2.6–4.2)	3.0 (2.3–4.0)	.645
MIP-1β	74 (62–89)	64 (53–77)	.321
RANTES	2011 (1378–2934)	891 (545–1454)	.016
bFGF	674 (596–761)	446 (384–518)	<.0005
G-CSF	6.4 (5.0–8.2)	6.4 (5.2–8.0)	.966
GM-CSF	4.4 (3.8–5.1)	2.4 (1.7–3.1)	<.0005
PDGFBB	11.7 (9.9–13.7)	8.2 (6.1–11.1)	.032
VEGF	160 (130–196)	150 (117–192)	.722

Values are mean (95% CI of mean) expressed in pg/mL of tissue supernatant. Logarithmic transformation was applied to obtain Gaussian distribution in all cases except those marked with dagger (†).

* p Values were generated by independent samples t-test; equality of variances were observed in all cases except IL17 where the corrected t was used.

Figure 1. Principal component analysis of 27-plex mediator measurement in rectal mucosa from subjects with IBS w/wo fructose intolerance, IBS controls and normal controls. Three PCs were extracted accounting for a cumulated 55% of the variance. The plot shows individual factor loadings of the two first components in a rotated solution. PC1 (30% variance) represents an adaptive pro-inflammatory component with high contribution from mediators like TNF, IFNγ, IL-17, IL-4 and IL-2. PC2 (13% variance) represents an early response pro-inflammatory component with high contribution from mediators like IL-8, IL-6, IL-9, bFGF and MIP-1α.