leptin and Candidiasis

Wstęp. Peptydy produkowane w przewodzie pokarmowym, tkance tłuszczowej i w mózgu odgrywają ważną rolę w wydzielaniu hormonu wzrostu (GH) oraz regulacji przyjmowania posiłków. Zgodnie z hipotezą molekularnego podobieństwa antygeny mikroorganizmów bytujących w przewodzie pokarmowym mogą stać się mechanizmem spustowym dla produkcji przeciwciał, które reagują krzyżowo z peptydami regulatorowymi i modyfikują ich działanie. Celem pracy była ocena stężenia greliny, leptyny, oreksynyA i αMSH oraz poziomu przeciwciał skierowanych przeciwko wymienionym peptydom u dzieci z idiopatycznym niedoborem wzrostu (ISS) i niedoborem GH (GHD) w odniesieniu do infekcji Helicobacter pylori (H.pylori) i zasiedlenia Candida albicans (C.albicans). Materiał i metody. Analiza obejmowała 89 dzieci z niedoborem wzrostu (w wieku 10,24±3,52 lat): 64 z ISS i 25 z GHD oraz 36 dzieci prawidłowego wzrostu (grupa kontrolna) (w wieku 11,41±2,72 lat). U każdego dziecka oceniono w surowicy stężenie greliny, leptyny, oreksynyA i αMSH (alpha-melanocyte-stimulating hormone), poziom przeciwciał IgG skierowanych przeciwko wymienionym peptydom oraz przeciwko H.pylori, zaś obecność C.albicans na podstawie badania próbki kału. Grupa kontrolna została dobrana tak, aby częstość występowania infekcji H.pylori i zasiedlenia C.albicans była podobna do grupy badanej. Wyniki. Poziom przeciwciał IgG przeciwko grelinie i leptynie był znamiennie wyższy w grupie ISS niż w grupie kontrolnej. Stężenie greliny było istotnie wyższe u dzieci z GHD niż w grupie kontrolnej, zaś stężenie leptyny (jak również wskaźnik masy ciała) istotnie niższe w grupie ISS niż w grupach GHD i kontrolnej. Nie wykazano różnic pomiędzy grupami w odniesieniu do stężenia oreksynyA i αMSH ani przeciwciał skierowanych przeciwko nim. Wnioski. Podwyższony poziom przeciwciał skierowanych przeciwko grelinie i leptynie u dzieci z ISS jest związany z upośledzeniem wzrastania i gorszymi przyrostami masy ciała, prawdopodobnie poprzez modyfikację aktywności greliny i leptyny. Możliwe, że te przeciwciała reagują krzyżowo z peptydami na skutek molekularnego podobieństwa między wymienionymi peptydami a H.pylori i C.albicans, jednak potrzebne są dalsze badania wyjaśniające tę kwestię.

Topics: Adolescent; alpha-MSH; Autoantibodies; Candida albicans; Candidiasis; Child; Female; Ghrelin; Growth Disorders; Helicobacter Infections; Helicobacter pylori; Humans; Leptin; Male; Orexins

Many of peptides synthesized in gastrointestinal tract (GI) and adipose tissues, regulate growth and food intake. The GI microflora is an antigenic source. Based on the molecular mimicry hypothesis, intestinal microbe-derived antigens may trigger the production of autoantibodies cross-reacting with some neuropeptides.. The aim of the study was to assess whether in idiopathic short stature (ISS) children with Candida albicans (C.albicans) colonisation and/or Helicobacter pylori (H.pylori) infection the autoantibodies (in positive levels) against selected neuropeptides [anti-NP Abs(+)]: ghrelin, leptin, orexin A, αMSH are more prevalent than in Controls.. The study group comprised 64 children with ISS and 36 children with normal height (Controls). In each child, IgG antibodies against H.pylori, ghrelin, leptin, orexin A and αMSH were assessed in serum, while presence of C.albicans - in stool samples.. The higher prevalence of anti-NP Abs(+) in ISS children with C.albicans and/or H.pylori than in normal height children with the colonization in question (34.4% vs 21.1%, p<0.01) was found. The prevalence of anti-NP Abs(+) in groups of children without C.albicans and H.pylori were low, anti-NP Abs(+) were detected in 9.4% of ISS children only, while in Controls they were not found.. In short children with C.albicans and/or H.pylori the incidence of autoantibodies against selected neuropeptides is high. It probably is connected with molecular mimicry between antigens of these microbiota and the mentioned peptides. It is tempting to speculate that presence of cross-reacting autoantibodies against regulatory neuropeptides may results in worse growth velocity. However, further studies are necessary to elucidate this issue.

Topics: Adolescent; alpha-MSH; Autoantibodies; Candida albicans; Candidiasis; Carrier State; Child; Child, Preschool; Cross Reactions; Female; Ghrelin; Growth Disorders; Helicobacter Infections; Helicobacter pylori; Humans; Leptin; Male; Molecular Mimicry; Neuropeptides; Orexins

We evaluated the host metabolic response to chronic varied stress during infection with the fungus Candida albicans. We used four groups of female Wistar rats: normal uninfected and unstressed, stressed, C. albicans infected and infected, and stressed. Infected rats reacted with rapid metabolic adjustments, evident as anorexia and body weight loss, partly mediated by glucocorticoids and TNF-alpha. Higher circulating levels of IL-6 and glucose (p < 0.05) revealed the progress and catabolic effect of the inflammatory response. Infected and stressed rats instead showed anorexia associated with infection and weight loss as the result of reduced food intake. This group exhibited a prompt reduction in circulating leptin on day 3 (p < 0.05), reduction in glucose levels and depletion of hepatic glycogen depots. We also evaluated the contribution of TNF-alpha, glucocorticoids, and food deprivation to liver damage. Lipid peroxidation in liver detected in the infected and infected-stressed groups was exacerbated by the glucocorticoid receptor antagonist RU 486, suggesting the modulatory activity of glucocorticoids, while hepatic fat accumulation and glycogen depletion decreased with anti-TNF-alpha treatment. Food deprivation exacerbated liver injury while the response to stress contributed to greater fungal colonization. Our findings emphasize the impact of metabolic alterations on tissue damage when the host immune activity is modulated by stress mediators.

Topics: Animals; Blood Glucose; Body Weight; Candidiasis; Eating; Female; Food Deprivation; Glucocorticoids; Hormone Antagonists; Leptin; Liver; Liver Glycogen; Mifepristone; Rats; Rats, Wistar; Stress, Psychological; Tumor Necrosis Factor-alpha

Circulating leptin concentrations are raised in animal models of inflammation and sepsis and leptin production is also increased in rodents by administration of endotoxin or cytokines. The purpose of this study was to investigate the effect of sepsis on serum leptin concentration and whether circulating leptin was related to tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) release in newborn infants. Plasma leptin, TNF-alpha and IL-6 were measured in 20 neonates with culture-proven sepsis as soon as sepsis was diagnosed and after recovery and in 15 healthy control infants. There was no significant difference in plasma leptin levels between septic and control infants (p > 0.05); there was also no difference in plasma leptin levels in septic neonates before and after therapy (p > 0.05). No relationship between leptin and TNF-alpha (r = 0.16, p > 0.05) or IL-6 (r = 0.12, p > 0.05) was identified. These findings suggest that a major role of leptin in acute neonatal sepsis appears unlikely.

Topics: Anti-Bacterial Agents; Body Mass Index; Candida albicans; Candidiasis; Escherichia coli Infections; Female; Humans; Infant, Newborn; Interleukin-6; Klebsiella Infections; Leptin; Male; Sepsis; Staphylococcal Infections; Tumor Necrosis Factor-alpha