POLYMORPHISMS OF GLUTATHIONE

S-TRANSFERASE M1 AND T1: GENETIC RISK FACTOR FOR

VITILIGO

POLYMORPHISMS OF GLUTATHIONE

S-TRANSFERASE M1 AND T1: GENETIC RISK FACTOR FOR

VITILIGOFabrizio Guarneri1, Alessio Asmundo2, Daniela Sapienza2, Serafinella Patrizia

Cannavò1

Fabrizio Guarneri1, Alessio Asmundo2, Daniela Sapienza2, Serafinella Patrizia

Cannavò11Section of Dermatology and 2Section of Legal

Medicine, Department of Territorial Social Medicine,

University of Messina, AOU “G. Martino”, Messina, Italy

1Section of Dermatology and 2Section of Legal Medicine,

Department of Territorial Social Medicine, University of Messina, AOU “G. Martino”, Messina,

Italy

The International School of Vitiligo

and Pigmentary Disorders

Barcelona, 2-5 November 2011

The International School of Vitiligo

and Pigmentary Disorders

Barcelona, 2-5 November 2011

GLUTATHIONE S-TRANSFERASE

GLUTATHIONE S-TRANSFERASE

Enzymes for detoxification of electrophyle compounds by conjugation with

glucuronates

Frequent genetic polymorphism

Main groups of polymorphisms: GSTA, GSTM,

GSTP, GSTT

The “null” genotype of GSTM1 and GSTT1 can be

found in a significant part of the general population

Enzymes for detoxification of electrophyle compounds by conjugation with

glucuronates

Frequent genetic polymorphism

Main groups of polymorphisms: GSTA, GSTM,

GSTP, GSTT

The “null” genotype of GSTM1 and GSTT1 can be

found in a significant part of the general population

GLUTATHIONE S-TRANSFERASE

GLUTATHIONE S-TRANSFERASE

NULL GENOTYPES IN GENERAL POPULATION

NULL GENOTYPES IN GENERAL POPULATION

GSTM1 GSTT1

Asmundo et al. 54.67% 24.67%

Griffiths et al. 36% 8%

Ada et al. 51.9% 17.3%

Uhm et al. 51.4% 52.6%

GSTM1 GSTT1

Asmundo et al. 54.67% 24.67%

Griffiths et al. 36% 8%

Ada et al. 51.9% 17.3%

Uhm et al. 51.4% 52.6%

The GSTM1 and GSTT1 “null” genotypes are linked

to skin cancers, psoriasis, allergic dermatoses

The GSTM1 and GSTT1 “null” genotypes are linked

to skin cancers, psoriasis, allergic dermatoses

GLUTATHIONE S-TRANSFERASE

GLUTATHIONE S-TRANSFERASE Enzymes for detoxification of electrophyle

compounds by conjugation with glucuronates

Frequent genetic polymorphism

Main groups of polymorphisms: GSTA, GSTM,

GSTP, GSTT

The “null” genotype of GSTM1 and GSTT1 can be

found in a significant part of the general population

Enzymes for detoxification of electrophyle compounds by conjugation with

glucuronates

Frequent genetic polymorphism

Main groups of polymorphisms: GSTA, GSTM,

GSTP, GSTT

The “null” genotype of GSTM1 and GSTT1 can be

found in a significant part of the general population

Uhm YK, Yoon SH, Kang IJ, Chung JH, Yim SV, Lee MH. Association of glutathione S-transferase gene polymorphisms (GSTM1 and GSTT1) of vitiligo in Korean population. Life Sci. 2007; 81 (3): 223-7.

Liu L, Li C, Gao J, Li K, Gao L, Gao T. Genetic polymorphisms of glutathione S-transferase and risk of vitiligo in the Chinese population. J Invest Dermatol. 2009; 129 (11): 2646-52.

Uhm YK, Yoon SH, Kang IJ, Chung JH, Yim SV, Lee MH. Association of glutathione S-transferase gene polymorphisms (GSTM1 and GSTT1) of vitiligo in Korean population. Life Sci. 2007; 81 (3): 223-7.

Liu L, Li C, Gao J, Li K, Gao L, Gao T. Genetic polymorphisms of glutathione S-transferase and risk of vitiligo in the Chinese population. J Invest Dermatol. 2009; 129 (11): 2646-52.

GLUTATHIONE S-TRANSFERASES AND

VITILIGO

GLUTATHIONE S-TRANSFERASES AND

VITILIGO

AIM OF THE STUDYAIM OF THE STUDY

To define the possible role of the GSTM1 and/or GSTT1 “null” genotype as a risk

factor for the development of vitiligo in a population of patients from a Mediterranean

area (Sicily and Calabria)

To define the possible role of the GSTM1 and/or GSTT1 “null” genotype as a risk

factor for the development of vitiligo in a population of patients from a Mediterranean

area (Sicily and Calabria)

MATERIALS AND METHODSMATERIALS AND METHODS

Study population: 58 consecutive vitiligo patients

(28 M, 30 F; mean age 25.22 ± 11.37 years),

all Caucasian, born and living in Sicily or Calabria

Control population: 150 healthy subjects, with a

similar age and sex distribution

Cell sample obtained by buccal swab

GSTM1 and GSTT1 genotyping

Study population: 58 consecutive vitiligo patients

(28 M, 30 F; mean age 25.22 ± 11.37 years),

all Caucasian, born and living in Sicily or Calabria

Control population: 150 healthy subjects, with a

similar age and sex distribution

Cell sample obtained by buccal swab

GSTM1 and GSTT1 genotyping

GSTM1 AND GSTT1 GENOTYPING

GSTM1 AND GSTT1 GENOTYPING

Extraction by “Chelex® 100” method PCR amplification Electrophoresis of PCR products on ultrathin

polyacrylamide gel Silver staining Bands of interest:

- 480 bp (GSTT1) - 215 bp (GSTM1)

Internal control: beta-globin gene

Extraction by “Chelex® 100” method PCR amplification Electrophoresis of PCR products on ultrathin

polyacrylamide gel Silver staining Bands of interest:

- 480 bp (GSTT1) - 215 bp (GSTM1)

Internal control: beta-globin gene

MATERIALS AND METHODSMATERIALS AND METHODS

Study population: 58 consecutive vitiligo patients

(28 M, 30 F; mean age 25.22 ± 11.37 years),

all Caucasian, born and living in Sicily or Calabria

Control population: 150 healthy subjects, with a

similar age and sex distribution

Cell sample obtained by buccal swab

GSTM1 and GSTT1 genotyping

Statistical analysis: Chi square test (significant if

p<0.05)

Study population: 58 consecutive vitiligo patients

(28 M, 30 F; mean age 25.22 ± 11.37 years),

all Caucasian, born and living in Sicily or Calabria

Control population: 150 healthy subjects, with a

similar age and sex distribution

Cell sample obtained by buccal swab

GSTM1 and GSTT1 genotyping

Statistical analysis: Chi square test (significant if

p<0.05)

RESULTSRESULTS

Genotype

GSTM1 Null ActivePatients 35 23Controls 82 68 p = 0.459

GSTT1 Null Active Patients 22 36Controls 19 113 p = 0.057

Genotype

GSTM1 Null ActivePatients 35 23Controls 82 68 p = 0.459

GSTT1 Null Active Patients 22 36Controls 19 113 p = 0.057

RESULTSRESULTS

GSTM1 GSTT1 Patients Controls

active active 15 49

active null 8 19 p = 0.535

null active 21 64 p = 0.858

null null 14 18 p = 0.041

GSTM1 GSTT1 Patients Controls

active active 15 49

active null 8 19 p = 0.535

null active 21 64 p = 0.858

null null 14 18 p = 0.041

ASSOCIATION BETWEEN THE “NULL” GST GENOTYPE AND

VITILIGO

ASSOCIATION BETWEEN THE “NULL” GST GENOTYPE AND

VITILIGO Uhm YK et al., Life Sci. 2007

Vitiligo associated with GSTM1 null and GSTM1/GSTT1 “double null”

Liu L et al., J Invest Dermatol. 2009Vitiligo associated with GSTT1 null and GSTM1/GSTT1 “double null”

Present studyVitiligo associated with GSTM1/GSTT1 “double null”

Uhm YK et al., Life Sci. 2007Vitiligo associated with GSTM1 null and GSTM1/GSTT1 “double null”

Liu L et al., J Invest Dermatol. 2009Vitiligo associated with GSTT1 null and GSTM1/GSTT1 “double null”

Present studyVitiligo associated with GSTM1/GSTT1 “double null”

AutoimmuneAutoimmune

ToxicToxic NeurogenicNeurogenic

VITILIGO: PATHOGENIC HYPOTHESES

VITILIGO: PATHOGENIC HYPOTHESES

Kostyuk VA et al., Antioxid Redox Signal 2010

We found significantly suppressed mRNA and protein expression of GST M1 isoform, and higher-than-normal levels of both 4-hydroxy-2-nonenal (HNE)-protein adducts and H2O2 in the cultures of keratinocytes derived from unaffected and affected skin of vitiligo patients

The broad spectrum of major cytokines, chemokines, and growth factors was dysregulated in both blood plasma and cultured keratinocytes of vitiligo patients

Exogenous HNE added to normal keratinocytes induceda vitiligo-like cytokine pattern, and H2O2 overproduction accompanied by adaptive upregulation of catalase and GSTM1 genes

Kostyuk VA et al., Antioxid Redox Signal 2010

We found significantly suppressed mRNA and protein expression of GST M1 isoform, and higher-than-normal levels of both 4-hydroxy-2-nonenal (HNE)-protein adducts and H2O2 in the cultures of keratinocytes derived from unaffected and affected skin of vitiligo patients

The broad spectrum of major cytokines, chemokines, and growth factors was dysregulated in both blood plasma and cultured keratinocytes of vitiligo patients

Exogenous HNE added to normal keratinocytes induceda vitiligo-like cytokine pattern, and H2O2 overproduction accompanied by adaptive upregulation of catalase and GSTM1 genes

DIFFERENT GSTM1/T1 GENOTYPESIN VITILIGO PATIENTS:

POSSIBLE EXPLANATIONS

DIFFERENT GSTM1/T1 GENOTYPESIN VITILIGO PATIENTS:

POSSIBLE EXPLANATIONS

Different “gene pool”

Variable importance of GST M1 and T1 in the “setup” of antioxidant mechanisms in different populations

Environmental conditions

Life style

Different “gene pool”

Variable importance of GST M1 and T1 in the “setup” of antioxidant mechanisms in different populations

Environmental conditions

Life style

FUTURE PERSPECTIVESFUTURE PERSPECTIVES

GST genotyping of various populations

Further studies on association between GST polymorphisms and vitiligo

Exact definition of the role of GSTs in the pathogenic mechanisms of vitiligo

GST genotyping of various populations

Further studies on association between GST polymorphisms and vitiligo

Exact definition of the role of GSTs in the pathogenic mechanisms of vitiligo

OUR NEW PROJECTOUR NEW PROJECT

Simultaneous definition of the genotype of all possibly

pathogenically relevant antioxidant enzymes

Correlation between each genotype and vitiligo

Calculation of the “antioxidant potential” of a subject and the individual contribution of each enzyme to it

Definition of individual disease risk and possible preventive measures

Study of connections among autoimmune, oxidative and neural mechanisms

Simultaneous definition of the genotype of all possibly

pathogenically relevant antioxidant enzymes

Correlation between each genotype and vitiligo

Calculation of the “antioxidant potential” of a subject and the individual contribution of each enzyme to it

Definition of individual disease risk and possible preventive measures

Study of connections among autoimmune, oxidative and neural mechanisms