Preventive strategy for Candida gut translocation during ischemia-reperfusion injury supervening on protein-calorie malnutrition

Gut Leakage of Fungal-Derived Inflammatory Mediators: Part of a Gut-Liver-Kidney Axis in Bacterial Sepsis

Sepsis is a life-threatening response to systemic infection. In addition to frank gastrointestinal (GI) rupture/puncture, sepsis can also be exacerbated by translocation of pathogen-associated molecular patterns (PAMPs) from the GI tract to the systemic circulation (gut origin of sepsis). In the human gut, Gram-negative bacteria and Candida albicans are abundant, along with their major PAMP components, endotoxin (LPS) and (1 → 3)-β-D-glucan (BG). Whereas the influence of LPS in bacterial sepsis has been studied extensively, exploration of the role of BG in bacterial sepsis is limited. Post-translocation, PAMPs enter the circulation through lymphatics and the portal vein, and are detoxified and then excreted via the liver and the kidney. Sepsis-induced liver and kidney injury might therefore affect the kinetics and increase circulating PAMPs. In this article, we discuss the current knowledge of the impact of PAMPs from both gut mycobiota and microbiota, including epithelial barrier function and the "gut-liver-kidney axis," on bacterial sepsis severity.

Protein Malnutrition During Juvenile Age Increases Ileal and Colonic Permeability in Rats

Protein malnutrition can lead to morphological and functional changes in jejunum and ileum, affecting permeability to luminal contents. Regarding the large intestine, data are scarce, especially at juvenile age. We investigated whether low-protein (LP) diet could modify ileal and colonic permeability and epithelial morphology in young rats. Isocaloric diets containing 26% (control diet) or 4% protein were given to male rats between postnatal days 40 and 60. LP-diet animals failed to gain weight and displayed decreased plasma zinc levels (a marker of micronutrient deficiency). In addition, transepithelial electrical resistance and occludin expression were reduced in their ileum and colon, indicating increased gut permeability. Macromolecule transit was not modified. Finally, LP diet induced shortening of colonic crypts without affecting muscle thickness. These data show that protein malnutrition increases not only ileum but also colon permeability in juvenile rats. Enhanced exposure to colonic luminal entities may be an additional component in the pathophysiology of protein malnutrition.

Effect of Candida albicans on Intestinal Ischemia-reperfusion Injury in Rats

Background:

Inflammation is supposed to play a key role in the pathophysiological processes of intestinal ischemia-reperfusion injury (IIRI), and Candida albicans in human gut commonly elevates inflammatory cytokines in intestinal mucosa. This study aimed to explore the effect of C. albicans on IIRI.

Methods:

Fifty female Wistar rats were divided into five groups according to the status of C. albicans infection and IIRI operation: group blank and sham; group blank and IIRI; group cefoperazone plus IIRI; group C. albicans plus cefoperazone and IIRI (CCI); and group C. albicans plus cefoperazone and sham. The levels of inflammatory factors tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and diamine oxidase (DAO) measured by enzyme-linked immunosorbent assay were used to evaluate the inflammation reactivity as well as the integrity of small intestine. Histological scores were used to assess the mucosal damage, and the C. albicans blood translocation was detected to judge the permeability of intestinal mucosal barrier.

Results:

The levels of inflammatory factors TNF-α, IL-6, and IL-1β in serum and intestine were higher in rats undergone both C. albicans infection and IIRI operation compared with rats in other groups. The levels of DAO (serum: 44.13 ± 4.30 pg/ml, intestine: 346.21 ± 37.03 pg/g) and Chiu scores (3.41 ± 1.09) which reflected intestinal mucosal disruption were highest in group CCI after the operation. The number of C. albicans translocated into blood was most in group CCI ([33.80 ± 6.60] ×10² colony forming unit (CFU)/ml).

Conclusion:

Intestinal C. albicans infection worsened the IIRI-induced disruption of intestinal mucosal barrier and facilitated the subsequent C. albicans translocation and dissemination.

Desnutrição neonatal e microbiota normal da cavidade oral em ratos

OBJETIVO: Avaliar a influência da desnutrição neonatal sobre o padrão e o crescimento de bactérias aeróbias, da microbiota normal da cavidade oral, em ratos Wistar adultos. MÉTODOS: O material da cavidade oral foi coletado através de swabs embebidos em 40µL de solução salina estéril e colocados em tubos estéreis contendo 960µL de brain heart infusion. Posteriormente, fez-se homogeneização de cada uma amostra. Então, destes 1.000µL, retirou-se 1µL e este foi semeado em placas de Petri contendo Agar-sangue e Levine para isolamento e identificação de bactérias Gram+ e Gram-, respectivamente. Essas placas foram incubadas em estufa bacteriológica a 37ºC, 48 horas, e as unidades formadoras de colônias que cresceram foram contadas e seus percentuais calculados. Para a bacterioscopia foram confeccionadas lâminas coradas pelo método de Gram. RESULTADOS: Do 5º ao 21º dia de vida os pesos corporais do grupo desnutrido (33,6g:42,8g, desvio-padrão=27,2g) foram menores (p<0,001) que os do grupo nutrido (52,5g:56,3g, desvio-padrão=24,0g). Dos 60 aos 120 dias de vida os pesos foram reduzidos no grupo desnutrido (248,2g:290,2g, desvio-padrão=220,2g), quando comparados aos do grupo nutrido (306,2g:319,4g, desvio-padrão=219,5g) teste Mann Whitney, p<0,05. A microbiota foi composta de menor número de bactérias no grupo nutrido (4,2x10(6) unidades formadoras de colônias, desvio-padrão=1,2x10(6) unidades formadoras de colônias de bactérias/mL), comparado ao grupo desnutrido (7,4x10(6) unidades formadoras de colônias, desvio-padrão=1,0x10(6) unidades formadoras de colônias de bactérias/mL) teste "t", (p=0,026). Das bactérias isoladas em culturas, observou-se um padrão bacteriano semelhante nos dois grupos, com 70% de bactérias gram-positivas e 30% de bactérias gram-negativas. CONCLUSÃO: A desnutrição neonatal foi efetiva em reduzir o peso corporal e aumentar o crescimento bacteriano. Embora o padrão bacteriano não tenha sido alterado, o aumento do crescimento bacteriano pode induzir a um desequilíbrio na microbiota oral desfavorecendo assim, o hospedeiro.

Effect of a novel phyto-compound on mucosal candidiasis: further evidence from an ex vivo study

OBJECTIVE

To isolate, identify and determine the prevalence of yeasts in the oral cavity of individuals and to test the minimum inhibitory dilution (MID) of Kolorex against the yeasts isolated.

METHODS

Twenty-nine individuals of both sexes aged on average 61.3 years were evaluated at the dental clinic in order to isolate and identify yeasts from their oral cavity, with and without lesions, and to determine the MID of the commercial phyto-product Kolorex against the strains isolated. The antifungal activity of the product tested was determined by the technique of dilution on a solid medium. Monocyte chemoattractant protein 1 (MCP-1) was measured by biotinylated antibody assay by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Yeasts of the genus Candida were detected in the saliva of 45.4% of the 11 individuals with a clinically healthy mouth and in 88.2% of 17 individuals with oral lesions. In the group with oral candidiasis we isolated in tongue and lesion, respectively, for each species: C. tropicalis (5.8% and 11.7%), C. glabrata (5.8% and 5.8%) and C. parapsilosis (0% and 5.8%), in addition to C. albicans as the only species or in association with others, respectively (64.7% and 70.5%). The total clonal formation unit (CFU) (counts/mL) in the saliva showed a higher mean value in the group with oral candidiasis (158.3x10(3)) than in the control group (64.6x10(3)). Most of the 70 test strains (95.7%) were sensitive to Kolorex by presenting a MID of 1:20. Sixty percent of strains from the 70 healthy sites showed results similar to those obtained with strains from oral lesions. Different results were mainly observed among different species. Patients with oral lesions showed a significant time-course increase of the level of monocyte chemoattractant protein 1 (MCP 1) as compared to those without lesions or to healthy people in whom Candida has not been detected (P<0.05). Co-culture with Kolorex using aliquots from the same patients with oral lesions inhibited such event (P<0.05).

CONCLUSION

Although this study was focused on oral cavity candidiasis, the results indicate the possibility of a broader use of the antifungal Kolorex in the prevention and treatment of mucosal candidiasis located elsewhere.