Anti-allergic effects of Vernonia amygdalina leaf extracts in hapten-induced atopic dermatitis-like disease in mice.
BACKGROUND
Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by pruritic and eczematous skin lesions. In this study, AD-like disease was induced in NC/Nga mice so as to evaluate the anti-allergic effects of Vernonia amygdalina leaf extracts (VAM).


METHODS
Forty NC/Nga mice were purchased for each of the two protocols (prophylactic and curative) of the study. Mice were randomly divided in groups of five or six after sensitization with 5% trinitrochlorobenzene (TNCB): aqueous extracts (VAM1), methanolic extracts (VAM2), hydrocortisone (HCT), buffer for the control (TNCB) and the normal mice (NORM) groups.


RESULTS
As for HCT, VAM1 and VAM2-pretreated mice showed significantly lower number of scratching behavior episodes (p < 0.01; vs. TNCB) following TNCB challenge. In addition, VAM1, VAM2 exerted a significant inhibitory effect on the development of AD skin symptoms (vs. TNCB group; p < 0.001), the production of IgE, TNF-alpha (p < 0.05), IL-5 and IFN-gamma (p < 0.01) (vs. TNCB group) and on the increase in ear thickness (p < 0.05) in prophylactic protocol. In the AD curative protocol, topical VAM1, VAM2 markedly improved skin lesions such as erythema/hemorrhage (p < 0.05), scaling/dryness, erosion/excoriation (p < 0.01) (vs. TNCB mice). Furthermore, a significant decrease in ear thickness was noted in VAM1, VAM2, HCT groups (vs. TNCB group; p < 0.05) as well as the serum total IgE, MCP-1 (p < 0.01) and eotaxin (p < 0.05). VAM2 also improved chronic eczema dermatitis skin symptoms in a patient.


CONCLUSIONS
Results from this report suggest that VAM extracts, known as ERK pathway inhibitor, prevent and improve atopic/eczema dermatitis syndrome.
Department of Environmental Medicine, Kochi University Medical School, Japan.
Nlandu Roger
NR
Ngatu
Maiko K
MK
Okajima
Maki
M
Yokogawa
Ryoji
R
Hirota
Mikiro
M
Takaishi
Masamitsu
M
Eitoku
Basilua Andre
BA
Muzembo
Asif Bhati
AB
Sabah
Takao
T
Saruta
Mitsuhiko
M
Miyamura
Tatsuo
T
Kaneko
Shigetoshi
S
Sano
Narufumi
N
Suganuma
D000287:Administration, Topical; D000293:Adolescent; D000818:Animals; D018926:Anti-Allergic Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018932:Chemokine CCL2 / Q000097:blood / Q000276:immunology; D016207:Cytokines / Q000097:blood / Q000276:immunology; D003876:Dermatitis, Atopic / Q000139:chemically induced / Q000188:drug therapy / Q000276:immunology*; D004195:Disease Models, Animal; D004423:Ear / Q000473:pathology; D004485:Eczema / Q000188:drug therapy; D006241:Haptens / Q000009:adverse effects; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018515:Plant Leaves / Q000737:chemistry*; D012867:Skin / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D013997:Time Factors; D035741:Vernonia / Q000737:chemistry*
D018926:Anti-Allergic Agents; C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D016207:Cytokines; D006241:Haptens; D010936:Plant Extracts; D007073:Immunoglobulin E