Probiotics Abstracts 1

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Treatment of irritable bowel syndrome with probiotics. An etiopathogenic approach at last
            (Bixquert Jiménez, 2009) Download
Irritable bowel syndrome (IBS) is the most common functional digestive disorder, and may affect 11-20% of the adult population in industrialized countries. In accordance with Rome III criteria (2006) IBS involves abdominal pain and bowel habit disturbance, which are not explained by structural or biochemical abnormalities. Several hypotheses attempt to account for the pathophysiology of IBS, but the etiology still remains uncertain or obscure, perhaps multifactorial. Abnormalities in colonic microflora have recently been suggested in such patients, as has abnormal small-intestine bacterial overgrowth (SIBO), or in particular a significant reduction in the amount of intraluminal Bifidobacteria or Lactobacilli, with consequences like the production of colonic gas, and motility or sensitivity disturbances of the intestinal tract. The disorder is difficult to treat, and the wide spectrum of non-drug and drug treatments shows our ignorance about the cause of the condition. Newer drugs, both pro- and anti-serotonin, have failed to show long-term efficacy or have been withdrawn due to concerns about harmful effects. Recent research has provided increasing support for the idea that disturbances of intestinal microbiota occur in patients with IBS, and that such abnormalities may contribute to IBS symptoms. Studies in Scandinavian countries in the last ten years emphasize the role of probiotics in the modulation of intestinal microbiota, and as a consequence in the regulation of the motility and hypersensitivity of the digestive tract. Although results between studies are difficult to compare because of differences in study design, probiotic dose, strain, and duration of therapy, some studies show symptom improvement. Lactobacilli are found among the normal bacterial flora of the gastrointestinal tract, and Lactobacillus plantarum (Lp) is one of the species frequently isolated from the human mucosa, which is capable of surviving the low pH of the stomach and duodenum, resisting the effect of bile acids in the upper small intestine when ingested, and temporarily colonizing the gastrointestinal tract by binding to the intestinal and colonic mucosa. Concurrent with colonization by Lp there is a decrease in bacterial groups with gas-producing ability, such as Veillonella spp. and Clostridia spp. Evidence has now accumulated to suggest the efficacy of certain probiotics like Lp299v, which may be capable of bringing about a significant reduction in pain, abdominal distension and flatulence, while increasing health-related quality of life in IBS.

Immunosenescence and anti-immunosenescence therapies: the case of probiotics.
            (Candore et al., 2008) Download
Aging is a complex process that negatively impacts the development of the immune system and its ability to function. Progressive changes in the T and B cell systems over the life span have a major impact on the capacity to respond to immune challenge. These cumulative age-associated changes in immune competence are termed immunosenescence. This process is mostly characterized by: (1) shrinkage of the T cell repertoire and accumulation of oligoclonal expansions of memory/effector cells directed toward ubiquitary infectious agents; (2) involution of the thymus and the exhaustion of naive T cells; and (3) chronic inflammatory status. Here we discuss possible strategies to counteract these main aspects of immunosenescence, in particular the role of the normalization of intestinal microflora by probiotics. A better understanding of immunosenescence and the development of new strategies to counteract it are essential for improving the quality of life of the elderly population.

Effect of functional yogurt NY-YP901 in improving the trait of metabolic syndrome.
            (Chang et al., 2011) Download
BACKGROUND/OBJECTIVES:  This study was aimed to assess the beneficial effects on metabolic syndrome of functional yogurt NY-YP901 (Namyang Dairy Product Co. Ltd and Nutra R&BT Inc., Seoul, Korea) supplemented with mixture of Streptococcus thermophilus, Lactobacillus acidophilus, Bifidobacterium infantis and extra-ingredients containing Bifidobacterium breve (CBG-C2), Enterococcus faecalis FK-23, fibersol-2 and so on. SUBJECTS/METHODS:  This study was designed as an 8-week randomized, double-blind, placebo-controlled, parallel study. Treatment and control groups consumed a functional yogurt NY-YP901 (150 ml) and a placebo yogurt twice a day, respectively, for 8 weeks. Body weight and body mass index (BMI), blood pressure, lipid profiles, fasting glucose with HbA1C and waist circumference were measured before and after treatment. Inclusion criteria were healthy individuals between the ages 20-65 years old who submitted an informed consent. RESULTS:  During the period August 2009 to December 2009, 101 healthy participants (31 males and 70 females) finished the study. Treatment group were 53 individuals, and the control group were 48 individuals. In the treatment group consuming NY-YP901, statistically significant beneficial changes were observed in body weight (treatment group vs control group=-0.24±1.50 vs +0.64±1.39 kg, P<0.05), BMI (-0.10±0.58 vs +0.24±0.50 kg/m(2), P<0.05 ) and low-density lipoprotein (LDL)-cholesterol (-7.71±14.14 vs -0.43±15.32 mg/dl, P<0.05) after 8 weeks. The change in other parameters was not different between the treatment and the control groups. CONCLUSIONS:  The functional yogurt NY-YP901 reduced LDL-cholesterol, body weight and BMI in the subjects at a 300-ml consumption daily for 8 weeks. From these findings, regular intake of functional yogurt NY-YP901 may be consequently related to improve metabolic syndrome.

Pathways in microbe-induced obesity.
            (Cox and Blaser, 2013) Download
Diet, host gene composition, and alterations in the intestinal microbiota can contribute to obesity. In microbe-induced obesity, metabolic changes stem from primary perturbation of the microbiota, consequent to modern changes in human biology. Microbiota disruption during early development can result in syndromes of metabolic dysfunction. We focus on the pathways involved in these interactions, particularly related to energy extraction and the role of inflammation in the metabolic phenotypes. Model physiologic systems and perturbations including gastric bypass surgery, pregnancy, and hibernation provide insight into the respective roles of the critical participants.

The effect of probiotics supplementation on Helicobacter pylori eradication rates and side effects during eradication therapy: a meta-analysis.
            (Dang et al., 2014) Download
BACKGROUND:  Previous meta-analyses reported that probiotics improve the effectiveness of Helicobacter pylori (H. pylori) eradication during antibiotic therapy, while results regarding a possible reduction of side effects remained inconclusive. Moreover, the effectiveness of different strains of probiotics has not been studied so far. It is further conceivable that probiotics will produce additional effects only if antibiotics are relatively ineffective. METHODS:  This meta-analysis includes eligible randomized controlled trials examining effects of probiotics supplementation on eradication rates (ER) and side effects, published up to May 2014. Sub-group analysis was performed to compare different probiotic strains and antibiotic therapies with different effectiveness in controls (ER <80% vs.>80%). Publication bias was assessed with funnel plots and Harbord's test. The quality of the trials was assessed with the Cochrane risk of bias tool. RESULTS:  Thirty-three RCTs involving a total of 4459 patients met the inclusion criteria in case of eradication rates of which 20 assessed total side effects in addition. Overall, the pooled eradication rate in probiotics supplementation groups was significantly higher than in controls (ITT analysis: RR 1.122, 95% CI 1.086-1.159, PP analysis: RR 1.114, 95% CI 1.070-1.159). Sub group-analysis could, however, confirm this finding only for four individual strains (Lactobacillus acidophilus, Lactobacillus casei DN-114001, Lactobacillus gasseri, and Bifidobacterium infantis 2036) and for relatively ineffective antibiotic therapies. There was a significant difference between groups in the overall incidence of side effects (RR 0.735, 95% CI 0.598-0.902). This result was, however, only confirmed for non-blinded trials. CONCLUSIONS:  The pooled data suggest that supplementation with specific strains of probiotics compared with eradication therapy may be considered an option for increasing eradication rates, particularly when antibiotic therapies are relatively ineffective. The impact on side effects remains unclear and more high quality trials on specific probiotic strains and side effects are thus needed.

Gut microbiota interactions with obesity, insulin resistance and type 2 diabetes: did gut microbiote co-evolve with insulin resistance
            (Esteve et al., 2011) Download
PURPOSE OF REVIEW:  The prevalence of obesity, insulin resistance and type 2 diabetes has steadily increased in the last decades. In addition to the genetic and environmental factors, gut microbiota may play an important role in the modulation of intermediary phenotypes leading to metabolic disease. RECENT FINDINGS:  Obesity and type 2 diabetes are associated with specific changes in gut microbiota composition. The mechanisms underlying the association of specific gut microbiota and metabolic disease include increasing energy harvest from the diet, changes in host gene expression, energy expenditure and storage, and alterations in gut permeability leading to metabolic endotoxemia, inflammation and insulin resistance. In some studies, the modifications of gut microbiota induced by antibiotics, prebiotics and probiotics led to improved inflammatory activity in parallel to amelioration of insulin sensitivity and decreased adiposity. However, these effects were mainly observed in animal models. Their extrapolation to humans awaits further studies. SUMMARY:  The fascinating role of gut microbiota on metabolic disease opens new avenues in the treatment of obesity, insulin resistance and type 2 diabetes. A co-evolutionary clue for microbiota and insulin resistance is suggested.

Diabetes, obesity and gut microbiota.
            (Everard and Cani, 2013) Download
The gut microbiota composition has been associated with several hallmarks of metabolic syndrome (e.g., obesity, type 2 diabetes, cardiovascular diseases, and non-alcoholic steatohepatitis). Growing evidence suggests that gut microbes contribute to the onset of the low-grade inflammation characterising these metabolic disorders via mechanisms associated with gut barrier dysfunctions. Recently, enteroendocrine cells and the endocannabinoid system have been shown to control gut permeability and metabolic endotoxaemia. Moreover, targeted nutritional interventions using non-digestible carbohydrates with prebiotic properties have shown promising results in pre-clinical studies in this context, although human intervention studies warrant further investigations. Thus, in this review, we discuss putative mechanisms linking gut microbiota and type 2 diabetes. These data underline the advantage of investigating and changing the gut microbiota as a therapeutic target in the context of obesity and type 2 diabetes.

Associations of the fecal microbiome with urinary estrogens and estrogen metabolites in postmenopausal women.
            (Fuhrman et al., 2014) Download
CONTEXT:  The gut microbiota may influence the risk of breast cancer through effects on endogenous estrogens. OBJECTIVE:  The objective of the study was to investigate whether urinary estrogens and estrogen metabolites are associated with the diversity and composition of the fecal microbiome. DESIGN AND SETTING:  This was a cross-sectional study among women enrolled in Kaiser Permanente of Colorado. PARTICIPANTS:  A total of 60 women drawn from a random sample of healthy postmenopausal women (aged 55-69 y), without current or recent use of antibiotics or hormone therapy and no history of cancer or gastrointestinal disease participated in the study. OUTCOME MEASURES AND METHODS: Creatinine-standardized urinary estrogens (estrone and estradiol) and 13 hydroxylated estrogen metabolites were measured in spot urines by liquid chromatography-tandem mass spectrometry. The fecal microbiome was assessed using pyrosequencing of 16S rRNA amplicons. General linear models were used to test for associations of diversity and composition of the fecal microbiome with parent estrogen (estrone + estradiol), total estrogens, and estrogen metabolites and the ratio of estrogen metabolites to parent estrogen, which has been predictive of postmenopausal breast cancer risk in previous studies. RESULTS:  The ratio of metabolites to parents was directly associated with whole-tree phylogenetic diversity (R = 0.35, P = .01). Relative abundances of the order Clostridiales (R = 0.32, P = .02) and the genus Bacteroides (R = -0.30, P = .03) were also correlated with the ratio of metabolites to parents. Associations were independent of age, body mass index, and study design factors. CONCLUSIONS:  Our data suggest that women with a more diverse gut microbiome exhibit an elevated urinary ratio of hydroxylated estrogen metabolites to parent estrogen. Further research is warranted to confirm and relate these findings to clinical disease.

Nutrient tasting and signaling mechanisms in the gut. II. The intestine as a sensory organ: neural, endocrine, and immune responses.
            (Furness et al., 1999) Download
The lining of the gastrointestinal tract is the largest vulnerable surface that faces the external environment. Just as the other large external surface, the skin, is regarded as a sensory organ, so should the intestinal mucosa. In fact, the mucosa has three types of detectors: neurons, endocrine cells, and immune cells. The mucosa is in immediate contact with the intestinal contents so that nutrients can be efficiently absorbed, and, at the same time, it protects against the intrusion of harmful entities, such as toxins and bacteria, that may enter the digestive system with food. Signals are sent locally to control motility, secretion, tissue defense, and vascular perfusion; to other digestive organs, for example, to the stomach, gallbladder, and pancreas; and to the central nervous system, for example to influence feeding behavior. The three detecting systems in the intestine are more extensive than those of any other organ: the enteric nervous system contains on the order of 10(8) neurons, the gastroenteropancreatic endocrine system uses more than 20 identified hormones, and the gut immune system has 70- 80% of the body's immune cells. The gastrointestinal tract has an integrated response to changes in its luminal contents. When this response is maladjusted or is overwhelmed, the consequences can be severe, as in cholera intoxication, or debilitating, as in irritable bowel syndrome. Thus it is essential to obtain a full understanding of the sensory functions of the intestine, of how the body reacts to the information, and of how neural, hormonal, and immune signals interact.

Investigation of the association between the fecal microbiota and breast cancer in postmenopausal women: a population-based case-control pilot study.
            (Goedert et al., 2015) Download
We investigated whether the gut microbiota differed in 48 postmenopausal breast cancer case patients, pretreatment, vs 48 control patients. Microbiota profiles in fecal DNA were determined by Illumina sequencing and taxonomy of 16S rRNA genes. Estrogens were quantified in urine. Case-control comparisons employed linear and unconditional logistic regression of microbiota α-diversity (PD_whole tree) and UniFrac analysis of β-diversity, with two-sided statistical tests. Total estrogens correlated with α-diversity in control patients (Spearman Rho = 0.37, P = .009) but not case patients (Spearman Rho = 0.04, P = .77). Compared with control patients, case patients had statistically significantly altered microbiota composition (β-diversity, P = .006) and lower α-diversity (P = .004). Adjusted for estrogens and other covariates, odds ratio of cancer was 0.50 (95% confidence interval = 0.30 to 0.85) per α-diversity tertile. Differences in specific taxa were not statistically significant when adjusted for multiple comparisons. This pilot study shows that postmenopausal women with breast cancer have altered composition and estrogen-independent low diversity of their gut microbiota. Whether these affect breast cancer risk and prognosis is unknown.

Systematic review: are probiotics useful in controlling gastric colonization by Helicobacter pylori
            (Gotteland et al., 2006) Download
Helicobacter pylori is a highly prevalent pathogen considered as an aetiological factor for gastroduodenal ulcers, and a risk factor for gastric adenocarcinoma and lymphoma in humans. Most subjects colonized by this micro-organism are asymptomatic and remain untreated. In symptomatic patients, the antibiotic treatment has a high cost and is not 100% effective because of resistance to antibiotics and to moderate patient compliance. This review discusses the role of probiotics as alternative solutions to assist in the control of H. pylori colonization in at-risk populations. The evidence that some strains of Lactobacillus and Bifidobacterium are able to inhibit H. pylori growth through the release of bacteriocins or organic acids, and may also decrease its adhesion to epithelial cells, is reviewed. In addition, probiotics have a possible role in the stabilization of the gastric barrier function and the decrease of mucosal inflammation. Other aspects that are considered are the contribution of probiotics to the healing of the gastric mucosa linked to their antioxidant and anti-inflammatory properties. Clinical trials in colonized adults and children are reviewed, and suggest that probiotics do not eradicate H. pylori but maintain lower levels of this pathogen in the stomach; in combination with antibiotics, probiotics may increase eradication rate and/or decrease adverse effects. Papers suggesting similar effects on H. pylori by foodstuffs such as berry juice and some milk proteins are quoted. Regular intake of these and other dietary products might constitute a low-cost, large-scale alternative solution applicable for populations at-risk for H. pylori colonization.

Gut microbiota and inflammation.
            (Hakansson and Molin, 2011) Download
Systemic and local inflammation in relation to the resident microbiota of the human gastro-intestinal (GI) tract and administration of probiotics are the main themes of the present review. The dominating taxa of the human GI tract and their potential for aggravating or suppressing inflammation are described. The review focuses on human trials with probiotics and does not include in vitro studies and animal experimental models. The applications of probiotics considered are systemic immune-modulation, the metabolic syndrome, liver injury, inflammatory bowel disease, colorectal cancer and radiation-induced enteritis. When the major genomic differences between different types of probiotics are taken into account, it is to be expected that the human body can respond differently to the different species and strains of probiotics. This fact is often neglected in discussions of the outcome of clinical trials with probiotics.

Oral administration of Lactobacillus reuteri GMNL-263 improves insulin resistance and ameliorates hepatic steatosis in high fructose-fed rats.
            (Hsieh et al., 2013) Download
BACKGROUND:  Type 2 diabetes mellitus (DM), characterized by peripheral insulin resistance, is the most common form of diabetes. Probiotics are live micro-organisms that, when administered in adequate amounts, confer delaying effect on DM development. In this study, the effects Lactobacillus reuteri GMNL-263 (Lr263), a new probiotic strain developed by our laboratory, on insulin resistance and the development of hepatic steatosis in high-fructose fed rats were explored. Furthermore, the relevant regulatory pathways involved were also investigated. METHOD:  Male Sprague-Dawley rats were fed a high-fructose diet with or without Lr263 administration for 14 weeks. The composition of fecal microbiota, oral glucose tolerance, glycated haemoglobin, insulin, leptin, C-peptide, and incretins were measured. The markers of liver injury, serum and hepatic lipids profile, activity of hepatic antioxidant enzyme, and proinflammatory cytokines in adipose tissue were investigated. Additionally, the expression of hepatic lipogenic genes and insulin signaling related genes in adipose tissue were also studied. Liver sections were examined for hepatic steatosis using hematoxylin-eosin staining. RESULTS:  The levels of serum glucose, insulin, leptin, C-peptide, glycated hemoglobin, GLP-1, liver injury markers, lipid profile in serum and liver were significantly increased in high-fructose-fed rats. However, after Lr263 administration, the elevation of these parameters was significantly suppressed. Feeding of Lr263 reversed the decreased number of bifidobacterium species and lactobacillus species and increased number of clostridium species induced by high fructose treatment. The decreased activities of hepatic antioxidant enzymes in HFD rats were dramatically reversed by Lr263 treatment. Concentrations of IL-6 and TNF-α in adipose tissue which were elevated in high fructose treatment were markedly decreased after Lr263 feeding. Decreased levels of PPAR-γ and GLUT4 mRNA after high fructose treatment were significantly enhanced by Lr263 administration. Lr263 consumption normalized the increased lipogenic gene (Srebp-1c, FAS, and Elvol6) expressions stimulated by high fructose. Administration of Lr263 significantly ameliorated hepatic steatosis observed in high fructose treated rats. CONCLUSION:  Our study provided evidences clarifying the effectiveness of Lr263 on reducing insulin resistance as well as hepatic steatosis formation in high-fructose-fed rats and suggested that Lr263 may be a promising therapeutic agent in treating type 2 diabetes.

Regulation of abdominal adiposity by probiotics (Lactobacillus gasseri SBT2055) in adults with obese tendencies in a randomized controlled trial.
            (Kadooka et al., 2010) Download
BACKGROUND/OBJECTIVES:  In spite of the much evidence for the beneficial effects of probiotics, their anti-obesity effects have not been well examined. We evaluated the effects of the probiotic Lactobacillus gasseri SBT2055 (LG2055) on abdominal adiposity, body weight and other body measures in adults with obese tendencies. SUBJECTS/METHODS:  We conducted a multicenter, double-blind, randomized, placebo-controlled intervention trial. Subjects (n=87) with higher body mass index (BMI) (24.2-30.7 kg/m(2)) and abdominal visceral fat area (81.2-178.5 cm(2)) were randomly assigned to receive either fermented milk (FM) containing LG2055 (active FM; n=43) or FM without LG2055 (control FM; n=44), and were asked to consume 200 g/day of FM for 12 weeks. Abdominal fat area was determined by computed tomography. RESULTS:  In the active FM group, abdominal visceral and subcutaneous fat areas significantly (P<0.01) decreased from baseline by an average of 4.6% (mean (confidence interval): -5.8 (-10.0, -1.7) cm(2)) and 3.3% (-7.4 (-11.6, -3.1) cm(2)), respectively. Body weight and other measures also decreased significantly (P<0.001) as follows: body weight, 1.4% (-1.1 (-1.5, -0.7) kg); BMI, 1.5% (-0.4 (-0.5, -0.2) kg/m(2)); waist, 1.8% (-1.7 (-2.1, -1.4) cm); hip, 1.5% (-1.5 (-1.8, -1.1) cm). In the control group, by contrast, none of these parameters decreased significantly. High-molecular weight adiponectin in serum increased significantly (P<0.01) in the active and control groups by 12.7% (0.17 (0.07, 0.26) microg/ml) and 13.6% (0.23 (0.07, 0.38) microg/ml), respectively. CONCLUSION:  The probiotic LG2055 showed lowering effects on abdominal adiposity, body weight and other measures, suggesting its beneficial influence on metabolic disorders.

Lactobacillus rhamnosus GG improves insulin sensitivity and reduces adiposity in high-fat diet-fed mice through enhancement of adiponectin production.
            (Kim et al., 2013) Download
Recently, a probiotic Lactobacillus rhamnosus GG (LGG) has shown several beneficial effects, including improved insulin sensitivity. To clarify the mechanism underlying the insulin-sensitizing effect of LGG, mice were orally administrated with LGG for 13 weeks, and their body weight, insulin sensitivity, and expression of genes related to glucose and lipid metabolism were examined. LGG-treated mice showed attenuated weight gain and enhanced insulin sensitivity in high fat diet group, while no change was observed in normal diet-fed group. The expression of fatty acid oxidative genes in the liver was increased and gluconeogenic genes were decreased. GLUT4 mRNA expression in skeletal muscle and adiponectin production in adipose tissue were significantly increased. This was corroborated with the increased activation of AMPK in skeletal muscle and adipose tissue. Taken together, these results indicate that LGG treatment improves insulin sensitivity and reduces lipid accumulation by stimulating adiponectin secretion and consequent activation of AMPK.

Cholesterol-lowering probiotics as potential biotherapeutics for metabolic diseases.
            (Kumar et al., 2012) Download
Cardiovascular diseases are one of the major causes of deaths in adults in the western world. Elevated levels of certain blood lipids have been reported to be the principal cause of cardiovascular disease and other disabilities in developed countries. Several animal and clinical trials have shown a positive association between cholesterol levels and the risks of coronary heart disease. Current dietary strategies for the prevention of cardiovascular disease advocate adherence to low-fat/low-saturated-fat diets. Although there is no doubt that, in experimental conditions, low-fat diets offer an effective means of reducing blood cholesterol concentrations on a population basis, these appear to be less effective, largely due to poor compliance, attributed to low palatability and acceptability of these diets to the consumers. Due to the low consumer compliance, attempts have been made to identify other dietary components that can reduce blood cholesterol levels. Supplementation of diet with fermented dairy products or lactic acid bacteria containing dairy products has shown the potential to reduce serum cholesterol levels. Various approaches have been used to alleviate this issue, including the use of probiotics, especially Bifidobacterium spp. and Lactobacillus spp.. Probiotics, the living microorganisms that confer health benefits on the host when administered in adequate amounts, have received much attention on their proclaimed health benefits which include improvement in lactose intolerance, increase in natural resistance to infectious disease in gastrointestinal tract, suppression of cancer, antidiabetic, reduction in serum cholesterol level, and improved digestion. In addition, there are numerous reports on cholesterol removal ability of probiotics and their hypocholesterolemic effects. Several possible mechanisms for cholesterol removal by probiotics are assimilation of cholesterol by growing cells, binding of cholesterol to cellular surface, incorporation of cholesterol into the cellular membrane, deconjugation of bile via bile salt hydrolase, coprecipitation of cholesterol with deconjugated bile, binding action of bile by fibre, and production of short-chain fatty acids by oligosaccharides. The present paper reviews the mechanisms of action of anti-cholesterolemic potential of probiotic microorganisms and probiotic food products, with the aim of lowering the risks of cardiovascular and coronary heart diseases.

Human originated bacteria, Lactobacillus rhamnosus PL60, produce conjugated linoleic acid and show anti-obesity effects in diet-induced obese mice.
            (Lee et al., 2006) Download
Many previous studies have reported that conjugated linoleic acid could be produced by starter culture bacteria, but the effects of the bacteria were not investigated. Moreover, there was no evidence of the conjugated linoleic acid-producing bacteria having potential health or nutritional effects related to conjugated linoleic acid, including reducing body fat. Here, we investigated the anti-obesity effect of Lactobacillus rhamnosus PL60, a human originated bacterium that produces t10, c12-conjugated linoleic acid, on diet-induced obese mice. After 8 weeks of feeding, L. rhamnosus PL60 reduced body weight without reducing energy intake, and caused a significant, specific reduction of white adipose tissue (epididymal and perirenal). Although the size of epididymal adipocytes was not reduced by L. rhamnosus PL60, apoptotic signals and UCP-2 mRNA levels increased in adipose tissue. Liver steatosis, a well known side effect of CLA, was not observed by L. rhamnosus PL60 treatment; on the contrary it seemed to be normalized. Results showed that the amount of conjugated linoleic acid produced by Lactobacillus rhamnosus PL60 was enough to produce an anti-obesity effect.

Obesity and the human microbiome.
            (Ley, 2010) Download
PURPOSE OF REVIEW:  Obesity was once rare, but the last few decades have seen a rapid expansion of the proportion of obese individuals worldwide. Recent work has shown obesity to be associated with a shift in the representation of the dominant phyla of bacteria in the gut, both in humans and animal models. This review summarizes the latest research into the association between microbial ecology and host adiposity, and the mechanisms by which microbes in the gut may mediate host metabolism in the context of obesity. RECENT FINDINGS:  Studies of the effect of excess body fat on the abundances of different bacteria taxa in the gut generally show alterations in the gastrointestinal microbiota, and changes during weight loss. The gastrointestinal microbiota have been shown to impact insulin resistance, inflammation, and adiposity via interactions with epithelial and endocrine cells. SUMMARY:  Large-scale alterations of the gut microbiota and its microbiome (gene content) are associated with obesity and are responsive to weight loss. Gut microbes can impact host metabolism via signaling pathways in the gut, with effects on inflammation, insulin resistance, and deposition of energy in fat stores. Restoration of the gut microbiota to a healthy state may ameliorate the conditions associated with obesity and help maintain a healthy weight.

The impact of perinatal probiotic intervention on the development of overweight and obesity: follow-up study from birth to 10 years.
            (Luoto et al., 2010) Download
BACKGROUND:  The achievements in combating the increasing trend of overweight and obesity have thus far been inadequate. The recently discovered instrumental role of the gut microbiota in host metabolism may offer a novel target in the prevention and management of obesity. OBJECTIVE:  To evaluate the impact of perinatal probiotic intervention on childhood growth patterns and the development of overweight during a 10-year follow-up. PATIENTS AND METHODS:  Altogether 159 women were randomized and double-blinded to receive probiotics (1 × 10(10) colony-forming units of Lactobacillus rhamnosus GG, ATCC 53103) or placebo 4 weeks before expected delivery; the intervention extending for 6 months postnatally. Anthropometric measurements of the children were taken at the ages of 3, 6, 12 and 24 months and at 4, 7 and 10 years in 113 (72%) children. RESULTS:  The excessive weight gain was detected to be two-parted; the initial phase of excessive weight gain initiating during fetal period and continuing until 24-48 months of age and a second phase of excessive weight gain starting after the age of 24-48 months. The perinatal probiotic intervention appeared to moderate the initial phase of excessive weight gain, especially among children who later became overweight, but not the second phase of excessive weight gain, the impact being most pronounced at the age of 4 years (P=0.063, analysis of variance for repeated measures). The effect of intervention was also shown as a tendency to reduce the birth-weight-adjusted mean body mass index at the age of 4 years (P=0.080, analysis of covariance). CONCLUSIONS:  Early gut microbiota modulation with probiotics may modify the growth pattern of the child by restraining excessive weight gain during the first years of life. This novel observation calls for further epidemiological and clinical trials, with precise data on early growth patterns and on confounding factors influencing weight development.

Gut bacterial microbiota and obesity.
            (Million et al., 2013) Download
Although probiotics and antibiotics have been used for decades as growth promoters in animals, attention has only recently been drawn to the association between the gut microbiota composition, its manipulation, and obesity. Studies in mice have associated the phylum Firmicutes with obesity and the phylum Bacteroidetes with weight loss. Proposed mechanisms linking the microbiota to fat content and weight include differential effects of bacteria on the efficiency of energy extraction from the diet, and changes in host metabolism of absorbed calories. The independent effect of the microbiota on fat accumulation has been demonstrated in mice, where transplantation of microbiota from obese mice or mice fed western diets to lean or germ-free mice produced fat accumulation among recipients. The microbiota can be manipulated by prebiotics, probiotics, and antibiotics. Probiotics affect the microbiota directly by modulating its bacterial content, and indirectly through bacteriocins produced by the probiotic bacteria. Interestingly, certain probiotics are associated with weight gain both in animals and in humans. The effects are dependent on the probiotic strain, the host, and specific host characteristics, such as age and baseline nutritional status. Attention has recently been drawn to the association between antibiotic use and weight gain in children and adults. We herein review the studies describing the associations between the microbiota composition, its manipulation, and obesity.

Supplementation of Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 in diet-induced obese mice is associated with gut microbial changes and reduction in obesity.
            (Park et al., 2013) Download
OBJECTIVE:  To investigate the functional effects of probiotic treatment on the gut microbiota, as well as liver and adipose gene expression in diet-induced obese mice. DESIGN:  Male C57BL/6J mice were fed a high-fat diet (HFD) for 8 weeks to induce obesity, and then randomized to receive HFD+probiotic (Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032, n = 9) or HFD+placebo (n = 9) for another 10 weeks. Normal diet (ND) fed mice (n = 9) served as non-obese controls. RESULTS:  Diet-induced obese mice treated with probiotics showed reduced body weight gain and fat accumulation as well as lowered plasma insulin, leptin, total-cholesterol and liver toxicity biomarkers. A total of 151,061 pyrosequencing reads for fecal microbiota were analyzed with a mean of 6,564, 5,274 and 4,464 reads for the ND, HFD+placebo and HFD+probiotic groups, respectively. Gut microbiota species were shared among the experimental groups despite the different diets and treatments. The diversity of the gut microbiota and its composition were significantly altered in the diet-induced obese mice and after probiotic treatment. We observed concurrent transcriptional changes in adipose tissue and the liver. In adipose tissue, pro-inflammatory genes (TNFα, IL6, IL1β and MCP1) were down-regulated in mice receiving probiotic treatment. In the liver, fatty acid oxidation-related genes (PGC1α, CPT1, CPT2 and ACOX1) were up-regulated in mice receiving probiotic treatment. CONCLUSIONS:  The gut microbiota of diet-induced obese mice appears to be modulated in mice receiving probiotic treatment. Probiotic treatment might reduce diet-induced obesity and modulate genes associated with metabolism and inflammation in the liver and adipose tissue.

Human intestinal microbiota and healthy ageing.
            (Tiihonen et al., 2010) Download
Earlier studies have indicated a decrease in anaerobes and bifidobacteria and a concomitant increase in enterobacteria in the intestinal microbiota with ageing. However, new data obtained with molecular techniques suggests decreased stability and increased diversity of the gut microbiota with advancing age. Further, no simple marker change in microbiota composition can be identified. Except for the reduced immune function, ageing itself may have relatively little effect on overall gastrointestinal function. Concomitant changes in nutrition, increased incidence of disease and corresponding use of medication with advancing age modify the composition of the microbial community of the gastrointestinal tract. This mini-review will focus on the recent findings on the gut microbiota of the elderly and on the potential benefits of probiotics, prebiotics and synbiotics.

 

 

 


References

Bixquert Jiménez, M (2009), ‘Treatment of irritable bowel syndrome with probiotics. An etiopathogenic approach at last’, Rev Esp Enferm Dig, 101 (8), 553-64. PubMedID: 19785495
Candore, G, et al. (2008), ‘Immunosenescence and anti-immunosenescence therapies: the case of probiotics.’, Rejuvenation Res, 11 (2), 425-32. PubMedID: 18442326
Chang, BJ, et al. (2011), ‘Effect of functional yogurt NY-YP901 in improving the trait of metabolic syndrome.’, Eur J Clin Nutr, 65 (11), 1250-55. PubMedID: 21697819
Cox, LM and MJ Blaser (2013), ‘Pathways in microbe-induced obesity.’, Cell Metab, 17 (6), 883-94. PubMedID: 23747247
Dang, Y, et al. (2014), ‘The effect of probiotics supplementation on Helicobacter pylori eradication rates and side effects during eradication therapy: a meta-analysis.’, PLoS One, 9 (11), e111030. PubMedID: 25365320
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