Probiotic effect of Bifidobacterium longum 51A and Weissella paramesenteroides WpK4 on gerbils infected with Giardia lamblia.

AIMS: The objective of this study was to assess the probiotic potential of genuine strains of Bifidobacterium longum 51A and Weissella paramesenteroides WpK4, in experimental giardiasis. METHODS AND RESULTS: The bacteria were administered orally to gerbils (Meriones unguiculatus) 10 days before oral infection with trophozoites of Giardia lamblia. After 7 days of infection, the animals were euthanized and portions of the duodenum were processed for histopathologic, histochemical and morphometric assessment. The height of the intestinal crypts and crypt/villi ratio were higher in infected groups (P < 0·05) than in noninfected groups. The area of mucus production was higher (P < 0·05) in infected animals pretreated with B. longum 51A than in other groups. The parasitic load of the animals that received both bacteria decreased significantly (P < 0·05) compared to the ones of the control group. CONCLUSIONS: Our results suggest a probiotic function of B. longum 51A and W. paramesenteroides WpK4 and may result in their use as a prophylactic and therapeutic alternative for promoting human and animal health. SIGNIFICANCE AND IMPACT OF THE STUDY: Bifidobacterium longum 51A and W. paramesenteroides WpK4 may constitute prophylactic alternatives, reversing the emergence of side effects and resistance observed in the conventional treatment of giardiasis.

Selection of a candidate probiotic strain of Pediococcus pentosaceus from the faecal microbiota of horses by in vitro testing and health claims in a mouse model of Salmonella infection.

AIMS: The aim of this study was to verify the suitable use of candidate 'probiotics' selected by in vitro tests and the importance of in vivo assays to nominate micro-organisms as probiotics and alternative prophylactic treatments for Salmonella Typhimurium infection. METHODS AND RESULTS: Thirty-three lactic acid bacteria (LAB) isolated from foal's faeces were assessed based on the main desirable functional in vitro criteria. Based on these results, Pediococcus pentosaceus strain 40 was chosen to evaluate its putative probiotic features in a mouse model of Salmonella infection. Daily intragastric doses of Ped. pentosaceus 40 for 10 days before and 10 days after Salmonella challenge (106 CFU of Salm. Typhimurium per mouse) led to a significant aggravation in mouse health by increasing weight loss, worsening clinical symptoms and anticipating the time and the number of deaths by Salmonella. Pediococcus pentosaceus modulated cell-mediated immune responses by up-regulation of the gene expression of the proinflammatory cytokines IFN-γ and TNF-α in the small intestine. CONCLUSION: The usual criteria were used for in vitro screening of a large number of LAB for desirable probiotic functional properties. However, the best candidate probiotic strain identified, Ped. pentosaceus #40, aggravated the experimental disease in mice. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings emphasize the need for prophylactic or therapeutic effectiveness to be demonstrated in in vivo models to make precise health claims.

Weissella paramesenteroides WpK4 reduces gene expression of intestinal cytokines, and hepatic and splenic injuries in a murine model of typhoid fever.

Diarrhoea in piglets by Salmonella and other pathogens can be a serious health problem. Non-drug treatments such as probiotic microorganisms have various effects on the gastrointestinal microbiota dysbiosis and host immune system modulation. The aim of this study was to demonstrate the suitable use of Weissella paramesenteroides WpK4 strain isolated from healthy piglets as an alternative prophylactic or therapeutic treatment against Salmonella Typhimurium. Out of 37 lactic acid bacteria isolates, 24 strains belonging to the Weissella and Lactobacillus genera were analysed in vitro for desirable probiotic characteristics. The W. paramesenteroides WpK4 strain fulfilled all in vitro tests: resistance to acidic pH and bile salts, hydrophobic cell surface, antagonism against bacterial pathogens, H2O2 production and exopolysaccharide secretion, and non-transferable resistance to antibiotics. Mice fed with WpK4 showed no signs of bacterial translocation to the liver or spleen and decreased Salmonella translocation to these organs. Significantly, WpK4 intake attenuated the weight loss, fostered the preservation of intestinal architecture and integrity, and promoted survival in mice following infection with Salmonella Typhimurium. In addition, WpK4 modulated immune cellular response by inhibiting the production of pro-inflammatory cytokines and inducing anti-inflammatory mediators. These findings validate the probiotic properties of W. paramesenteroides WpK4 strain, and its eventual use in piglets.

Isolation, enumeration, molecular identification and probiotic potential evaluation of lactic acid bacteria isolated from sheep milk

Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%), E. durans (31.25%) and E. casseliflavus (12.5%). No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0) and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime, oxacillin and streptomycin and sensible to clindamycin, erythromycin and penicillin. The resistance to ciprofloxacin, gentamicin, tetracycline and vancomycin varied among tested species. All tested enterococci strongly inhibited (P<0.05) Escherichia coli and Listeria monocytogenes, moderately inhibited E. faecalis and Staphylococcus aureus and did not inhibit Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium and also one E. durans sample isolated from sheep milk. Four samples of E. faecium, one of E. durans and one of E. casseliflavus presented the best probiotic potential...

Espécies de bactérias ácido-lácticas foram identificadas em nível molecular em leite das raças ovinas Lacaune, Santa Inês e suas mestiças, e o seu potencial probiótico in vitro foi avaliado. As espécies identificadas foram Enterococcus faecium (56,25%), E. durans (31,25%) e E. casseliflavus (12,5%). Nenhuma outra espécie de bactéria ácido-láctica, como Lactobacillus sp., foi identificada. A maioria dos enterococos isolados foi resistente ao pH gástrico (2.0) e a 0,3% de oxgall. Todos os enterococos testados foram resistentes à ceftazidima, oxacilina e estreptomicina e sensíveis à clindamicina, eritromicina e penicilina. A resistência à ciprofloxacina, gentamicina, tetraciclina e vancomicina variou entre as amostras. Todos os enterococos testados inibiram fortemente (P<0,05) Escherichia coli e Listeria monocytogenes, inibiram moderadamente E. faecalis e Staphylococcus aureus e não inibiram Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium e uma amostra de E. durans isolada de leite de ovelha. Quatro amostras de E. faecium, uma de E. durans e uma de E. casseliflavus apresentaram o melhor potencial probiótico...

In vitro assessment of functional properties of lactic acid bacteria isolated from faecal microbiota of healthy dogs for potential use as probiotics.

Lactic acid bacteria were isolated and identified in the faeces of Chinese Crested and Yorkshire terrier pups and their probiotic features were investigated in vitro. Thirty seven isolates were identified as Lactobacillus or Enterococcus. Out of these isolates, 31 were lactic acid bacteria (LAB) and belonged to the species Lactobacillus reuteri (16/37; 43.3%), Lactobacillus animalis (7/37; 18.9%), Lactobacillus acidophilus (3/37; 8.1%), Lactobacillus sanfranciscensis (2/37; 5.4%), Lactobacillus murinus (2/37; 5.4%), and Lactobacillus paraplantarum (1/37; 2.7%), while six other LAB isolates were Enterococcus spp. (6/37; 16.2%). Strains were tested for resistance to gastric acidity (pH 2.5 for 3 h) and bile salts (0.3% ox gall), cell surface hydrophobicity by microbial adhesion to solvents, antagonism against pathogenic bacteria (Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica serovar Typhimurium and Listeria monocytogenes), production of hydrogen peroxide, and antibiotic susceptibility. Thirty four strains were highly resistant to acidic conditions with slight (18 strains) to moderate (16 strains) growth inhibition by bile salts. Seven isolates had highly hydrophobic cellular surfaces and 28 strains exhibited strong antagonism against the bacterial pathogens tested, although 8 isolates tested against Leptospira interrogans had no effect on pathogen growth. All isolates produced low rates of hydrogen peroxide. Based on these results, two Lactobacillus strains showed promising probiotic-related features and merit investigation as probiotics for dogs.

[Critical illness polyneuropathy: case report]. / Polineuropatia do paciente crítico. Registro de caso.

The critical illness polyneuropathy has an acute onset and an axonal predominantly motor nature. It occurs in sepsis or in multiple organ failure usually requiring mechanical ventilation in critical care units. Electroneuromyography corroborates the diagnosis. Usually it courses satisfactorily. We report on a 35-year-old female patient who, after a permanence in a critical care unit due to sepsis and removal of a dead phetus, developed tetraparesis. She had an important improvement in four months. Electromyography showed reduction of amplitude of motor and sensory action potentials, positive waves and fibrillations. The sural nerve biopsy showed axonmyelinic neuropathy. These findings are consistent with those in literature and we believe they support the diagnosis of critical illness neuropathy.