Influence de divers types d&amp;rsquo;ob&amp;eacute;sit&amp;eacute; exp&amp;eacute;rimentale sur la r&amp;eacute;sistance de la souris &amp;agrave; &amp;lcaron;infection par &lt;i&gt;Salmonella typh&amp;iacute;muriu&lt;/i&gt;&lt;i&gt;m&lt;/i&gt; et &lt;i&gt;Klebsiella pneumoniae&lt;/i&gt;

Conge, G; Gouache, P.; Joyeux, Y; Goichot, J; Fournier, J.M.

doi:10.1159/000177423

Cited by 15 publications

(5 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In basal conditions there was a severe defect in anti‐microbial activity in both SVF and macrophages from ob/ob mice. An immune deficiency has already been described in obesity both in humans and animal models (Conge et al, 1988; Stallone, 1994). The decrease in candidacidal activity of the macrophages from obese mice has to be related to the decrease in bactericidal capacity of mononuclear phagocytes described in humans (Chandra, 1980; Palmblad et al, 1980), although their phagocytic capacity was unchanged (Chandra, 1980).…”

Section: Discussionmentioning

confidence: 94%

“…However, research in human obesity suggests that phagocytes may be particularly affected (Bray, 1985; Chandra, 1991; Stallone, 1994). In animals, differences in immune responsiveness have been described between mouse strains and between different types of obesity (Conge et al, 1981, 1988; Stallone, 1994), and recent findings demonstrate functional and phenotypic abnormalities in macrophages from Zucker rats (Plotkin et al, 1996) or ob/ob mice (Loffreda et al, 1998; Lee et al, 1999). According to the authors, these macrophage defects could be explained by leptin deficiency observed in ob/ob mice (Loffreda et al, 1998; Lee et al, 1999).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Altered macrophage-like functions of preadipocytes in inflammation and genetic obesity

et al. 2001

View full text Add to dashboard Cite

We recently demonstrated that preadipocytes exhibit functional features of macrophages, such as phagocytosis and anti-microbial activity, suggesting that preadipose cells could play a role in the inflammatory process or immune response. The aim of this study was to compare these functions of both macrophages and cells from stroma-vascular fraction (SVF) of the adipose tissue in two different situations, obesity and inflammation, characterized by alterations in immune responsiveness. We demonstrated that ob/ob mice exhibited strong decrease in antimicrobial activity of both macrophages and SVF. This defect is compensated in SVF, at least in part, by an enhancement of phagocytosis that does not seem to be due to an increased macrophage number. In vitro leptin treatment of SVF and macrophages from obese mice did not restore their immune defects. Thioglycollate treatment of lean and obese mice induced an inflammatory process that led to an increase in macrophage activity in both strains. This stimulation also observed in SVF from lean mice is not present in obese ones. This work demonstrated that SVF immune functions could be modified in different pathological situations such as inflammation and obesity and sustained the new physiological role of preadipocytes in these processes.

show abstract

Section: Discussionmentioning

confidence: 94%

mentioning

confidence: 99%

Altered macrophage-like functions of preadipocytes in inflammation and genetic obesity

et al. 2001

View full text Add to dashboard Cite

show abstract

“…There are now a number of reports demonstrating that leptin or leptin receptor deficiency disables host defense against bacterial infections (12–15, 19, 33–35). Unlike other models of leptin or leptin receptor deficiency, the l/l mouse is neither obese nor hyperglycemic and thus provides an excellent model for assessing the importance of distinct LepR mediated signaling events in host defense against bacterial infection in the absence of endocrine abnormalities.…”

Section: Discussionmentioning

confidence: 99%

Ablation of Leptin Receptor-Mediated ERK Activation Impairs Host Defense against Gram-Negative Pneumonia

Mancuso

Myers

Goel

et al. 2012

The Journal of Immunology

View full text Add to dashboard Cite

The adipocyte-derived hormone, leptin, plays an important role in regulating energy homeostasis and the innate immune response against bacterial infections. Leptin’s actions are mediated by signaling events initiated by phosphorylation of tyrosine residues on the long form of the leptin receptor. We recently reported that disruption of leptin receptor mediated STAT3 activation augmented host defense against pneumococcal pneumonia. In this report, we assessed leptin receptor mediated ERK activation, a pathway that was ablated in the l/l mouse through a mutation of the tyrosine 985 residue in the leptin receptor, to determine its role in host defense against bacterial pneumonia in vivo and in alveolar macrophage antibacterial functions in vitro. l/l mice exhibited increased mortality and impaired pulmonary bacterial clearance following intratracheal challenge with Klebsiella pneumoniae. The synthesis of cysteinyl-LTs was reduced and that of PGE2 enhanced in alveolar macrophages in vitro and the lungs of l/l mice following infection with K.pneumoniae in vivo. We also observed reduced phagocytosis and killing of K. pneumoniae in AMs from l/l mice that was associated with reduced reactive oxygen intermediate production in vitro. cAMP, known to suppress phagocytosis, bactericidal capacity, and reactive oxygen intermediate production, was also increased 2-fold in AMs from l/l mice. Pharmacologic blockade of PGE2 synthesis reduced cAMP levels and overcame the defective phagocytosis and killing of bacteria in AMs from l/l mice in vitro. These results demonstrate that leptin receptor mediated ERK activation plays an essential role in host defense against bacterial pneumonia and in leukocyte antibacterial effector functions.

show abstract

“…Reasons for this inconsistency remain unclear. Studies in murine models of obesity have shown failure to contain both influenza (14, 15) and bacterial (16, 17) pneumonias with consequent lung injury and death. Subsequent work examining influenza has focused on the role of altered adaptive immune response in obesity (18–21).…”

Section: Introductionmentioning

confidence: 99%

Hyperleptinemia is associated with impaired pulmonary host defense

Ubags¹,

Stapleton²,

Vernooy³

et al. 2016

JCI Insight

View full text Add to dashboard Cite

We have previously reported that obesity attenuates pulmonary inflammation in both patients with acute respiratory distress syndrome (ARDS) and in mouse models of the disease. We hypothesized that obesity-associated hyperleptinemia, and not body mass per se, drives attenuation of the pulmonary inflammatory response and that this e_ect could also impair the host response to pneumonia. We examined the correlation between circulating leptin levels and risk, severity, and outcome of pneumonia in 2 patient cohorts (NHANES III and ARDSNet-ALVEOLI) and in mouse models of diet-induced obesity and lean hyperleptinemia. Plasma leptin levels in ambulatory subjects (NHANES) correlated positively with annual risk of respiratory infection independent of BMI. In patients with severe pneumonia resulting in ARDS (ARDSNet-ALVEOLI), plasma leptin levels were found to correlate positively with subsequent mortality. In obese mice with pneumonia, plasma leptin levels were associated with pneumonia severity, and in obese mice with sterile lung injury, leptin levels were inversely related to bronchoalveolar lavage neutrophilia, as well as to plasma IL-6 and G-CSF levels. These results were recapitulated in lean mice with experimentally induced hyperleptinemia. Our findings suggest that the association between obesity and elevated risk of pulmonary infection may be driven by hyperleptinemia.

show abstract

Influence de divers types d’obésité expérimentale sur la résistance de la souris à &lcaron;infection par <i>Salmonella typhímuriu</i><i>m</i> et <i>Klebsiella pneumoniae</i>

Cited by 15 publications

References 16 publications

Altered macrophage-like functions of preadipocytes in inflammation and genetic obesity

Altered macrophage-like functions of preadipocytes in inflammation and genetic obesity

Ablation of Leptin Receptor-Mediated ERK Activation Impairs Host Defense against Gram-Negative Pneumonia

Hyperleptinemia is associated with impaired pulmonary host defense

Contact Info

Product

Resources

About