Preventative effects of a probiotic, Lactobacillus salivarius ssp. salivarius, in the TNBS model of rat colitis

Table 1 Criteria for assessment of macroscopic colonic damage

Score	Criteria
0	No damage
1	Hyperemia, no ulcers
2	Linear ulcer with no significant inflammation
3	Linear ulcer with inflammation at one site
4	Two or more sites of ulceration/inflammation
5	Two or more major sites of ulceration and inflammation or
	one site of ulceration/inflammation, extending >1 cm along the
	length of the colon
6-10	If damage covers >2 cm along the length of the colon, the score
	is increased by one, for each additional centimeter of involvement

Table 2 Criteria for assessment of microscopic colonic damage

Mucosal epithelium

Ulceration: none (0); mild - surface (1); moderate (2); extensive-full thickness (3)

Crypts

Mitotic activity: lower third (0); mild mid-third (1); moderate mid-third (2); upper third (3)

Mucus depletion: none (0); mild (1); moderate (2); severe (3)

Lamina propria

Mononuclear infiltrate: none (0); mild (1); moderate (2); severe (3)

Granulocyte infiltrate: none (0); mild (1); moderate (2); severe (3)

Vascularity: none (0); mild (1); moderate (2); severe (3)

Submucosal

Mononuclear infiltrate: none (0); mild (1); moderate (2); severe (3)

Granulocyte infiltrate: none (0); mild (1); moderate (2); severe (3)

Edema: none (0); mild (1); moderate (2); severe (3)

Maximum score: 27. Modified from Stucchi et al[28].

Table 3 Effects of L. salivarius ssp. salivarius (5×10⁸ CFU/rat·d) treatment on macroscopic damage score, extent of the inflammatory lesion along the colon and changes in colon weight in TNBS experimental colitis in rats

Group (n = 10)	Damage score(0-10)	Extent of damage(cm)	Colon weight(mg/cm)
Non-colitic	0	0	63.3±2.5
TNBS control	6.5 (5-8)	3.4±0.3	209.7±17.0
TNBS probiotic	5 (3-7)a	2.3±0.4b	143.3±11.8b

Damage score for each rat was assigned according to the criteria described in Table 1 and data are expressed as median (range). Extent of damage and colon weight data are expressed as mean±SE.

^aP<0.05,

^bP<0.01 vs TNBS control. All colitic groups differ significantly from non-colitic group.

Table 4 Myeloperoxidase (MPO) activity, total GSH content, TNF-α and LTB4 levels in colon specimens from non-colitic rats, TNBS control colitic rats and TNBS colitic rats treated with L. salivarius ssp. salivarius (5×10⁸ CFU/rat·d)

Group (n = 10)	MPO activity (units MPO/g)	GSH (nmol/g)	LTB4 (ng/g)	TNF-α (pg/g)
Non-colitic	23.4±7.2	1 540±41	2.9±0.4	441.5±39.1
TNBS control	180.6±21.9d	1 087±51d	6.5±0.9d	782.9±60.1d
TNBS probiotic	105.3±26.0ad	1 252±42ad	6.9±0.8d	509.4±68.2b

Data are expressed as mean±SE.

^aP<0.05,

^bP<0.01 vs TNBS control group;

^dP<0.01 vs non-colitic group.