Probiotic
Microbes, immunoregulation, and the gut
Rook G.A., Brunet L.R.
Two distinct, but rapidly converging, areas of research (the hygiene hypothesis and the study of probiotic/prebiotic effects) have emphasised the need to understand, and ultimately to manipulate, our physiological interactions with commensal flora, and with other transient but harmless organisms from the environment that affect immunoregulatory circuits. The story began with allergic disorders but now inflammatory bowel disease is increasingly involved.
Gut. 2005 Mar;54(3):317-20.
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Mesalazine for diverticular disease of the colon - a new role for an old drug
Tursi A., Brandimarte G., Giorgetti G.M., Modeo M.E.
Colonic diverticulosis is among the most common diseases of developed countries. Its prevalence is approximately 5 - 10% of the population by age 50, and 30, 50 and 66% of those > 50, > 70 and > 85years of age, respectively. Antibiotics have been successfully used in the treatment of uncomplicated diverticular disease; however, the use of mesalazine (alone or in combination with antibiotics) in treating uncomplicated diverticulitis has been successfully developed in recent years. Indeed, mesalazine (with or without antibiotics) showed significant superiority in improving the severity of symptoms, bowel habits, and in preventing symptomatic recurrence of diverticulitis over antibiotics alone.
More-over, in light of some preliminary results, it is probable that the association of mesalazine with probiotics may in the future be the first-choice treatment for mild-to-moderate uncomplicated attacks of acute diverticulitis.
Expert Opin Pharmacother. 2005 Jan;6(1):69-74
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Intestinal immunity of Escherichia coli NISSLE 1917: a safe carrier for therapeutic molecules
Westendorf A.M., Gunzer F., Deppenmeier S., Tapadar D., Hunger J.K., Schmidt M.A., Buer J., Bruder D.
The development of novel approaches that allow accurate targeting of therapeutics to the intestinal mucosa is a major task in the research on intestinal inflammation. For the first time, a live genetically modified bacterial strain has been approved by Dutch authorities as a therapeutic agent for experimental therapy of intestinal bowel disease (IBD) in humans. Genetically modified probiotics can very well be used as carriers for localized antigen delivery into the intestine. Therapeutic safety, however, of such a carrier organism, is crucial, especially when a specific probiotic strain has to be used under diseased conditions. In this study, we tested the potential of Escherichia coli NISSLE 1917 to serve as a safe carrier for targeted delivery of recombinant proteins to the intestinal mucosa. In a well-defined and very sensitive immunological system, we demonstrate that intestinal recombinant E. coli NISSLE 1917 has no effect on migration, clonal expansion and activation status of specific CD4(+) T cells, neither in healthy mice nor in animals with acute colitis. Furthermore, recombinant E. coli NISSLE 1917 has no effect on the induction or breakdown of peripheral T-cell tolerance in an autoimmune environment. The excellent colonization properties of E. coli NISSLE 1917 render this strain an ideal candidate as carrier organism for gut-focused in situ synthesis of therapeutic molecules.
FEMS Immunol Med Microbiol. 2005 Mar 1;43(3):373-84.
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Commensal bacteria in the gut: learning who our friends are
Yan F., Polk D.B.
PURPOSE OF REVIEW: Recent evidence has shown that commensal bacteria regulate intestinal physiology, development, and function. This review focuses on new insights into the effects of these organisms on health and disease.
RECENT FINDINGS: Gastrointestinal tract development and function is determined by communication between the intestinal epithelium and commensal bacteria. Important regulatory interactions between these cells are being defined with early evidence indicating both beneficial and harmful consequences to the host. A subgroup of these bacteria overlaps with probiotic organisms that have preventative and therapeutic potential for diarrhea, inflammatory bowel disease (IBD), atopy, and other diseases, whereas evidence indicates some "nonpathogenic" commensal bacteria may promote an environment conducive to IBD, cancer, and other diseases.
SUMMARY: Progress in understanding the relation between commensal bacteria and human health is likely to promote the identification of new approaches to disease prevention and treatment.
Curr Opin Gastroenterol. 2004 Nov;20(6):565-71
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Increased incidence of inflammatory bowel disease: the price of the decline of infectious burden?
Feillet H., Bach J.F.
PURPOSE OF REVIEW: It is now apparent that the increase in the incidence of autoimmune and allergic diseases in Western countries is explained by the decrease in infections. The question is posed to determine whether a similar explanation can be proposed for the increased incidence of inflammatory bowel disease.
RECENT FINDINGS: Studies performed in murine experimental models of inflammatory bowel disease have shown that colitis onset can be prevented by bacteria, bacterial extracts, or helminths. Particular interest was given to probiotics (either live or killed), which protect from disease in a toll-like receptor 9 dependent fashion. This protective effect involves regulatory cytokines as indicated by in vitro studies on human inflamed colonic cells. At the clinical level, there is strong suggestion but still limited proof that probiotics improve inflammatory bowel disease through immunoregulatory mechanisms.
SUMMARY: Converging clinical and experimental data strongly suggest the protective nonspecific role of infections on inflammatory bowel disease independently from the triggering role of some specific bacteria. The extension to inflammatory bowel disease of the hygiene hypothesis opens new therapeutic perspectives including the revisiting of probiotics and other forms of exposure to bacteria or parasite components.
Curr Opin Gastroenterol. 2004 Nov;20(6):560-4.
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Reduction of Escherichia coli O157 in finishing beef cattle by various doses of Lactobacillus acidophilus in direct-fed microbials
Younts-Dahl S.M., Osborn G.D., Galyean M.L., Rivera J.D., Loneragan G.H., Brashears M.M.
Our objective was to evaluate the effects of three doses of Lactobacillus acidophilus strain NP51 and a combination treatment of strains NP51 and NP45 on prevalence of Escherichia coli O157 in cattle.
Three hundred steers were assigned randomly to 60 pens (five steers per pen) and received one of five treatments:
(i) control, no added direct-fed microbial;
(ii) HNP51, high dose of NP51 at 10(9) CFU per steer daily;
(iii) MNP51, NP51 at 10(8) CFU per steer daily;
(iv) LNP51, low dose of NP51 at 10(7) CFU per steer daily; and
(v) NP51+45, NP51 at 10(9) CFU per steer daily and NP45 at 106 CFU per steer daily.
All direct-fed microbial treatments included Propionibacterium freudenreichii at 10(9) CFU per steer. Individual rectal fecal samples were collected on arrival and every 28 days throughout the feeding period. Fecal and hide samples were collected on the day of harvest. Samples were analyzed for presence of E. coli O157 using immunomagnetic separation methods. Cattle receiving HNP51, MNP51, and LNP51 had a lower prevalence (P < 0.01) of E. coli O157 throughout the feeding period compared with the controls, and the dose response for NP51 was a linear decrease in prevalence with increasing dose (P < 0.01). No decrease in prevalence for cattle receiving the combination NP51+45 was detected compared with controls (P = 0.15). E. coli O157 prevalences averaged across collection times were 23.9, 10.5, 9.9, 6.8, and 17.3% for cattle in the control, LNP51, MNP51, HNP51, and NP51 +45 groups, respectively. Least squares mean estimates of fecal prevalence at harvest of E. coli O157 were 31.7, 12.5, 17.4, 8.2, and 41.6% among cattle in the control, LNP51, MNP51, HNP51, and NP51+45 groups, respectively. Least squares mean estimates of the percentage of positive hide samples at harvest were 8.7, 5.9, 4.8, 3.4, and 8.6% among cattle in the control, LNP51, MNP51, HNP51, and NP51+45 groups, respectively.
The greatest decrease in E. coli O157 carriage was achieved using NP51 at 10(9) CFU per steer.
Food Prot. 2005 Jan;68(1):6-10
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Probiotic potential of 3 lactobacilli strains isolated from breast milk
Martin R., Olivares M., Marin M.L., Fernandez L., Xaus J., Rodriguez J.M.
Breast milk is an important factor in the initiation, development, and composition of the neonatal gut microbiota. In a previous study, the authors isolated lactic acid bacteria from milk of healthy mothers. Since some of the identified isolates belonged to the genus Lactobacillus, the objective of this work was to evaluate the probiotic potential of 2 Lactobacillus gasseri and 1 Lactobacillus fermentu strains. Different assays, including survival to conditions simulating those existing in the gastrointestinal tract, production of antimicrobial compounds, adherence to intestinal cells, production of biogenic amines, degradation of mucin, enzymatic profile, and pattern of antibiotic resistance, were performed. Globally, the results showed that the probiotic potential of lactobacilli isolated from milk of healthy mothers is, at least, similar to that of the strains commonly used in commercial probiotic products. This fact, together with the presence of prebiotic substances, indicates that breast milk is a natural synbiotic food.
J Hum Lact. 2005 Feb;21(1):8-17.
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Comparison of probiotics and lactulose in the treatment of minimal hepatic encephalopathy in rats
Jia L., Zhang M.H.
AIM: To compare the efficacy of probiotic preparation Golden Bifid and lactulose on rat experimental model of minimal hepatic encephalopathy (MHE) induced by thioactamide (TAA).
METHODS: MHE was induced by intraperitoneal injection of TAA (200 mg/kg) every 24 h for two consecutive days. Thirty-six male MHE models were then randomly divided into 3 groups: TAA group (n = 12) received tap water ad libitum only; lactulose group (n = 12) and probiotics group (n = 12) were gavaged, respectively with 8 mL/kg of lactulose and 1.5 g/kg of probiotic preparation Golden Bifid (highly concentrated combination of probiotic) dissolved in 2 mL of normal saline, once a day for 8 d (from the 5(th) d before the experiment to the 3(rd) d of the experiment). The latency of brainstem auditory evoked potentials (BAEP) I was used as an objective index of MHE. The incidence of MHE, the level of serum endotoxin, ammonia, liver function and histological grade of hepatic injury of rats were examined individually.
RESULTS: There were no overt HE and rat deaths in 3 groups. The incidence of MHE, the levels of blood ammonia and endotoxin in TAA group, which were 83.3% (10/12), 168.33+/-15.44 mg/dL and 0.36+/-0.04 EU/mL, respectively, were significantly higher than those in lactulose group, which were 33.3% (4/12), 110.25+/-7.39 mg/dL and 0.19+/-0.02 EU/mL, and probiotics group, which were 33.3% (4/12), 108.58+/-10.24 mg/dL and 0.13+/-0.03 EU/mL respectively (P < 0.001). It showed that either probiotics or lactulose could significantly lower the level of hyperammonemia and hyper-endotoxemia, lighten centrolobular necrotic areas as well as inflammatory reaction in the liver of rats, normalize the latency of BAEP, and decrease the incidence of MHE. However, no significant differences were observed between these two groups (P >0.05).
CONCLUSION: Probiotic compound Golden Bifid is at least as useful as lactulose for the prevention and treatment of MHE. Probiotic therapy may be a safe, natural, well-tolerated therapy appropriate for the long-term treatment of MHE.
World J Gastroenterol. 2005 Feb 14;11(6):908-11
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