The “vicious cycle" of enteropathogens, malnutrition, and impaired childhood development, and multifaceted opportunities for intervention.

<p>Figure adapted from Nutr Rev. 2008 September; 66(9): 487–505 <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0002125#pntd.0002125-Guerrant1" target="_blank">[15]</a>.</p

Figure 1

<p>A. Body weight gain (% initial weight) from experimental uninfected and undernourished groups under a low protein diet. APOE 4/4 targeted replacement (APOE 4/4 TR) mice (n = 17) showed 643 a better growth response in comparison with APOE 3/3 targeted replacement (APOE 3/3 TR) mice (n = 8). <b>B.</b> Body weight gain (% initial infection weight) from experimental mice challenged by a compounded malnutrition and <i>Cryptosporidium parvum</i> insult. Undernourished mice were orally inoculated with 10⁷- unexcysted oocysts diluted in 100 µl of PBS. APOE deficient mice show impaired growth following <i>Cryptosporidium parvum</i> infection as compared to the other groups. Results are shown as mean ±SEM.</p

Quantitative real-time PCR assays from experimental mice for the following ileal mRNA transcripts: (A) cationic amino acid transporter (CAT-1); (B) arginase 1; (C) Toll-like receptor 9 (TLR9); and (D) Inducible nitric oxide synthase (iNOS).

<p>Experimental mice were challenged by a compounded malnutrition and <i>Cryptosporidium parvum</i> insult and samples were harvested on day 7 post-<i>C. parvum inoculum</i>. Wild-type, APOE knockout, and APOE targeted replacement mice (APOE 3/3 TR and APOE 4/4 TR) were orally inoculated with 10⁷- unexcysted oocysts diluted in 100 µl of PBS. Groups have at least 4 per groups and the results are shown as mean ±SEM and expressed after β-actin normalization.</p

Fecal shedding of parasites in weaned undernourished C57BL/6 mice orally inoculated with 10⁷-unexcysted <i>Cryptosporidium parvum</i> oocysts per mouse (given in100 µL of PBS) on day 7 after the onset of the low protein diet.

<p>Results are shown in a log scale a mean±SEM. <i>Cryptosporidium parvum</i> stool oocyst shedding was determined by qRT PCR. Data were expressed as number of parasites per miligram of stool and percentage and number of infected mice with measurable oocyst shedding per day after <i>Cryptosporidium parvum</i> challenge. N above the bars means the number of mice still showing oocyst shedding.</p

Primers used in the study.

<p>Primers used in the study.</p

Luminex assays from experimental mice for the following ileal pro-inflammatory cytokines: (A) Interleukin 1-β; (B) Interleukin-17; (C) Interferon-gamma; and (D) Tumor necrosis factor alpha.

<p>Experimental mice were challenged by a compounded malnutrition and <i>Cryptosporidium parvum</i> insult and samples were harvest on day 7 post-<i>C. parvum inoculum</i>. Wild-type, APOE knock-out, and APOE targeted replacement mice (APOE 3/3 TR and APOE 4/4 TR) were orally inoculated with 10⁷-unexcysted oocysts diluted in 100 µl of PBS. Groups have at least 4 per groups and the results are shown as mean ±SEM and are expressed in pg/ml. MNC = uninfected undernouorished control group. MNI = undernourished infected group.</p

Lipid profile of experimental undernourished mice following <i>Cryposporidium parvum</i> infection (mice orally infected with 10⁷ unexcysted oocysts).

<p>*p<0.001 ApoE Ko vs all;</p><p>** p = 0.05 ApoE TR 4/4 vs ApoE TR 3/3;</p><p>*** p<0.001 ApoE Ko vs all;</p>#<p>p<0.05 ApoE Ko vs ApoE TR 4/4 by Student <i>t</i> Test.</p

Figure 3

<p>A. Representative ileal histology from orally <i>Cryptosporidium parvum</i> infected mice. Wild-type, APOE knock-out, and APOE targeted replacement mice (APOE 3/3 TR and APOE 4/4 TR) were fed with a low protein diet during 7 days then infected with 10⁷-unexcysted <i>Cryptosporidium parvum</i> oocysts and euthanized seven days after infection. H&E ×400. Scale bar 10 µM. <b>B</b>. Ileal villus height; <b>C</b>. crypt depth, and <b>D</b>. villus-crypt ratio from wild-type, APOE knock-out, and APOE targeted replacement mice (APOE 3/3 TR and APOE 4/4 TR). Morphometrics was done from hematoxylin and eosin stained-sections in at least four animals per group at low magnification. Data are presented as mean±SEM. Comparisons were performed by Students unpaired <i>T</i> test. Villi and crypts were measured only when their full longitudinal axis was found.</p

Fecal MPO, Fecal alpha-1-antitrypsin (A1AT), and plasma LPS, FABP and SAA each predicts subsequent growth impairment.

<p>a: For MPO, <i>p</i> = 0.028; n = 266 when correcting for age and gender, and independent of breastfeeding status (that showed no correlation in these 6-26m old children) and of age. b: For A1AT, n = 237; <i>p</i> = 0.042; and A1AT also correlates with “catchup WAZ” as well, <i>p</i> = 0.035 after correcting for age and gender. c: For urine L/M, higher values correlated (controlling for age and gender) with impaired growth (delta HAZ) (<i>r</i> = -0.173; <i>p</i> = 0.009; n = 230). d: For plasma LPS (ie lower LUM), higher values correlated with impaired growth (delta HAZ) (<i>r</i> = 0.151; <i>p</i> = 0.017; n = 251). e: For plasma FABP, higher values correlated with impaired growth (delta HAZ) (r = -0.134; <i>p</i> = 0.042; n = 231). f: For plasma SAA, higher values correlated with impaired growth (delta HAZ) (r = -0.132; p = 0.046; n = 231).</p

Frequencies of biomarker testing, including 13 tests on plasma, 4 on fecal and L/M absorption testing on urine as shown.

<p>*Of 326 children with samples obtained within 1 month of study start.</p