Ron Riley

Toxicology and Mycotoxin Research Unit

USDA Agricultural Research Service, Athens, Georgia

Should the Focus be on Aflatoxins Alone?

To be covered:

•Aflatoxin (AFB) and Fumonisin (FB) in Guatemala.

•FB as a Confounder in Studies of AFB Health Effects

“Sown to be eaten, it is the sacred sustenance of the men who were made of maize. Sown to make money, it means famine for the men who were made of maize”

From “Men of Maize” Miguel Angel Asturias (Translation of the Popol Vuh – sacred book of the Maya)

ppb n SEM

All 180a 640 30

Clean 97b 582 16

Moldy 1011a 58 273

ppm n SEM

All 2.6 640 0.1

Clean 2.6 582 0.1

Moldy 2.4 58 0.3

1.1/3.80.4/4.6

8.8/4.6

283/1.9

2.0/2.2

12/3.8

85/2.5

26/1.0

10/1.4

279/2.4

117/1.1

13/0.3

195/1.3

16/1.4

308/4.0

70/1.8

200/2.3

30/1.7

105/1.0

34/2.5

19/1.0

Fumonisin and Aflatoxin B1 in Guatemala in 2012 (Torres et al., unpublished)

AFB1 (ppb)/Total FB (ppm)

0/1.1

1992- present - Disruption of sphingolipid metabolism as the mechanism of action for fumonisin-induced diseases in-----

•Humans?•Horse•Pig•Goat•Rabbit•Mink•Rat•Mouse•Turkey•Chicken•Duck•Catfish•Trout•Carp•Corn seedlings•Tomato

The concentration of fumonisin B1 in urine and the Sa 1-P/So 1-P ratio in blood are significantly correlated in a dose-dependent manner.

To be covered:

•Aflatoxin (AFB) and Fumonisin (FB) in Guatemala.

•FB as a Confounder in Studies of AFB Health Effects

1992- present - Disruption of sphingolipid metabolism as the mechanism of action for fumonisin-induced diseases in-----

•Humans•Horse•Pig•Goat•Rabbit•Mink•Rat•Mouse•Turkey•Chicken•Duck•Catfish•Trout•Carp•Corn seedlings•Tomato

GSTP+ foci/or nodules

Total (>5 cells/cm2)

Control 0.04

AFB only 5.02

FB1 only 1.65

AFB1FB1 71.8

“Groundnuts and Mealies”Jackie Caestairs 1989)

“…..given the interactions found experimentally, the co-contamination of crops by aflatoxins and fumonisins, and the fact that both toxins occur in populations with a high prevalence of HBV infection, a role for fumonisins in HCC is plausible.” (page 93, col 3)

Vascular maturation

Neurogenesis

AngiogenesisBarrier integrity

Lymphocyte trafficking

Cell motility Hearing

Neuronal excitation

Cytoskeletal rearrangement

Sphingosine 1-phosphate extracellular and “Inside-Out” signaling through the G protein coupled receptors - S1PR1-5

+/-

+/-

Sph

N

C+

+

-/-

-/-

S1P

GPCR S1PR1-5

S1P

RBC

plateletsHDL

Sph salvage and dhSph de novoand SphK1/2 activation

S1P & dhS1P

Mural-Diego-Rivera-21-photo-by-Mirairi-Erdoza

Traditional processing of maize in Central America

Financial and Administrative Support 1999 – 2012

Guatemala and Central America Red SICTA - IICA/COSUDE CONAGRAB, Comision Nacional de Granos Basicos Institute of Science and Technology Agricultural (ICTA) Consejo Nacional de Ciencia y Tecnología (CONCYT), FODECYT COMUDEB, Hospital General San Juan de Dios Puesto de Salud Santa Isabel, Escuintla Foundation for Food Nutrition for Central America and Panama (FANCAP) Institute of Nutrition of Central America and Panama (INCAP) Laboratorio Diagnóstico Molecular, CA. Pan American Health OrganizationUnited States of America USDA Foreign Agricultural Service (FAS) ILSI NA Technical Committee on Food Toxicology and Safety Assessment USDA Agricultural Research Service (ARS) National Institute of Environmental Health Sciences (US NIEHS) NIH Eunice Kennedy Shriver National Institute of Child Health & Human Development grant (1RC4HD067971-01 )