Composition and metabolism of the intestinal microbiota in consumers and non-consumers of yogurt

The objective of the present study was to evaluate the impact of a regular consumption of yogurt on the composition and metabolism of the human intestinal microbiota. Adult subjects were selected on the basis of daily food records and divided into two groups: yogurt consumers (at least 200 g yogurt consumed per d, n 30); non-consumers (no yogurt, n 21). Their faecal microbiota was analysed using molecular methods (in situ hybridisation and PCR amplification combined with separation by denaturing gel electrophoresis) and its metabolic characteristics were assessed by measuring glycosidase, P-glucuronidase and reductase activities and profiling SCFA, neutral sterols and bile acids. The yogurt starter Lactobacillus delbrueckii ssp. bulgaricus (identity confirmed by 16S rRNA sequencing) was detected in 73% of faecal samples from fermented milk consumers v. 28% from non-consumers (P=0.003). In yogurt consumers, the level of Enterobacteriaceae was significantly lower (P=0.006) and 13-galactosidase activity was significantly increased (P=0.048). In addition, within this group, 3-galactosidase activity and the Bifidobacterium population were both positively correlated with the amount of fermented milk ingested (r 0.66, P<0.0001 and r 0.43, P=0.018, respectively). Apart from these effects, which can be considered beneficial to the host, no other major differences could be detected regarding the composition and metabolic activity of intestinal microbiota.     

Brussels sprouts, inulin and fermented milk alter the faecal microbiota of human microbiota-associated rats as shown by PCR-temporal temperature gradient gel electrophoresis using universal, Lactobacillus and Bifidobacterium 16S rRNA gene primers

We investigated the effect of Brussels sprouts, inulin and a fermented milk on the faecal microbiota diversity of human microbiota-associated (HMA) rats by PCR-temporal temperature gradient gel electrophoresis (PCR-TTGE) using universal and group-specific 16S rRNA gene primers. The HMA rats were submitted to a control diet for 10 d (initial time), then switched to the experimental diets for 4 weeks (final time). Using universal primers, the mean degree of similarity between all faecal samples at initial time was 80.8 %. In the group consuming the control diet throughout the experiment, the mean degree of similarity between the PCR-TTGE profiles at initial v. final time was 76.8 %, reflecting a spontaneous temporal variation. The mean degree of similarity between control and experimental groups at final time was lower, 72.4 %, 74.4 % and 75.6 % for inulin, Brussels sprouts and fermented milk, respectively, indicating a dietary effect on the predominant populations. Using specific primers, bifidobacteria could be detected only in those rats that had consumed inulin, showing a specific increasing effect of this dietary compound. The Lactobacillus population was very heterogeneous at initial time but tended to homogenize within each dietary group. At final time, caecal contents were collected for analysis of SCFA and beta-glucuronidase activity. Inulin and Brussels sprouts increased the butyrate and acetate proportion, respectively, while the fermented milk did not modify the caecal biochemistry. This experiment shows for the first time that cruciferous vegetables are able to alter the diversity and the metabolic activities of the digestive microbiota in HMA rats.     

Probiotic-enriched milk and dairy products increase gut microbiota diversity: a comparative study

Targeting gut microbiota with probiotics has emerged as a promising nutritional approach for the prevention of obesity and metabolic syndrome. Cultured dairy products can be effectively employed for the delivery of probiotics to the gut as well as for the support of growth and survival of probiotic bacteria. The purpose of this study was to characterize the effects of probiotic-enriched pasteurized milk and dairy products (Greek-style yogurt and cottage cheese) of different origins (cow, goat, and camel) on taxonomic composition of the mouse gut microbiota. We hypothesized that cultured dairy products can be an effective vector for the delivery of probiotics to the gut because of its nutritional value, acidic nature, and long shelf-life. Mice were fed a standard low fat, plant polysaccharide-rich (LF/PP) diet supplemented with the probiotic-enriched milk and dairy products for 5 weeks. Next generation sequencing of DNA from mouse fecal samples was used to characterize the bacterial relative abundance. Mice fed a diet supplemented with camel milk demonstrated characteristic changes in the gut microbiota, which included an increase in relative abundance of order Clostridiales and genus Anaerostipes. Mice fed a diet supplemented with the probiotic-enriched cow cheese exhibited an increase in the relative abundance of order Clostridiales, family Ruminococcaceae, and family Lachnospiraceae. The results obtained and their bioinformatics analysis support the conclusion that camel milk and the probiotic cow cheese induce changes in the mouse gut microbiota, which can be characterized as potentially beneficial to health compared to the changes associated with a standard diet. These findings imply that probiotic-enriched milk and dairy products can be highly effective for the delivery and support of probiotic bacteria of the gut.     

Effect on blood lipids of two daily servings of Camembert cheese. An intervention trial in mildly hypercholesterolemic subjects

As a concentrated source of saturated fat, cheese consumption is considered to be associated with increased cholesterolemia and generally forbidden in dietary guidelines for adults with hypercholesterolemia. The aim of this study was to evaluate the impact of saturated fatty acids on lipid parameters and blood pressure with regards to different types of dairy products: Camembert and full-fat yoghurt. One-hundred and fifty-nine moderate hypercholesterolemic subjects without treatment were instructed to consume two full-fat yoghurts (2?×?125?g) per day for 3 weeks (run-in period) and then for a further period of 5 weeks, either two full-fat yoghurts or two 30?g servings of Camembert cheese per day. We observed that over the 5-week daily consumption of two servings of Camembert cheese, blood pressure and serum lipids did not change in moderate hypercholesterolemic subjects. These results suggest that fermented cheese such as Camembert could be consumed daily without affecting serum lipids or blood pressure.     

Substitutions of dairy product intake and risk of stroke: a Danish cohort study

Low fat dairy products are part of dietary guidelines to prevent stroke. However, epidemiological evidence is inconclusive with regard to the association between dairy products and stroke. We therefore investigated associations for substitutions between dairy product subgroups and risk of total stroke and stroke subtypes. We included 55,211 Danish men and women aged 50–64 years without previous stroke. Baseline diet was assessed by a food frequency questionnaire. Cases were identified through a national register and subsequently verified. The associations were analyzed using Cox proportional hazard regression. During a median follow-up of 13.4 years, we identified 2272 strokes, of which 1870 were ischemic (318 large artery atherosclerotic, 839 lacunar, 102 cardioembolic, 98 other determined types, 513 of unknown type), 389 were hemorrhages (273 intracerebral, 116 subarachnoid) and 13 of unknown etiology. Substitution of semi-skimmed fermented milk or cheese for whole-fat fermented milk was associated with a higher rate of ischemic stroke [semi-skimmed fermented milk: hazard ratio (HR) = 1.20 (95% confidence interval (CI) 0.99–1.45), cheese: HR = 1.14 (95% CI 0.98–1.31) per serving/day substituted] and substitutions of whole-fat fermented milk for low-fat milk, whole-fat milk or buttermilk were associated with a lower rate [low-fat milk: HR = 0.85 (95% CI 0.74–0.99), whole-fat milk: HR = 0.84 (95% CI 0.71–0.98) and buttermilk: HR = 0.83 (95% CI 0.70–0.99)]. We observed no associations for substitutions between dairy products and hemorrhagic stroke. Our results suggest that intake of whole-fat fermented milk as a substitution for semi-skimmed fermented milk, cheese, buttermilk or milk, regardless of fat content, is associated with a lower rate of ischemic stroke.     

Food supplementation with milk fermented by Lactobacillus casei DN-114 001 protects suckling rats from rotavirus-associated diarrhea

Group A rotavirus is the leading cause of diarrhea among children aged 3-36 mo worldwide. Introducing fermented milk products into the infant diet has been proposed for the prevention or treatment of rotavirus diarrhea. The preventive effect of milk fermented by the Lactobacillus casei strain DN-114 001 was studied in a model of germfree suckling rats supplemented daily from d 2 of life and infected with SA11 rotavirus at d 5 (RF group). One group was supplemented with nonfermented milk (RM) and two uninfected groups (CM and CF) received either nonfermented or fermented milk. Frequency and severity of diarrhea were observed. Rats were killed at various times from 0 to 120 h postinfection (p.i.). Bacteria were measured in the intestine, and rotavirus antigens were detected by ELISA in fecal samples and in different parts of the intestine. Histologic observations were made, including vacuolation, morphology of intestinal villi and number of mucin cells. RM rats had diarrhea for 6 d; compared with the CM group, they had alterations of the intestinal mucosa characterized by cellular vacuolation 48 and 72 h p.i. and a lower number of sulfated mucin cells 72 and 96 h p.i. (P: < 0.05). Early supplementation with fermented milk significantly decreased the clinical signs of diarrhea from 24 to 144 h p.i. (P: < 0.05) and prevented rotavirus infection in all sections of the intestine. Histologic lesions of the small intestine were greatly reduced (P: < 0.05) and the number of mucin cells remained unchanged. The data are discussed with respect to the possibility of reducing rotavirus diarrhea in young children by consumption of fermented milk.     

Intake of Dairy Products in Relation to Periodontitis in Older Danish Adults

This cross-sectional study investigates whether calcium intakes from dairy and non-dairy sources, and absolute intakes of various dairy products, are associated with periodontitis. The calcium intake (mg/day) of 135 older Danish adults was estimated by a diet history interview and divided into dairy and non-dairy calcium. Dairy food intake (g/day) was classified into four groups: milk, cheese, fermented foods and other foods. Periodontitis was defined as the number of teeth with attachment loss ≥3 mm. Intakes of total dairy calcium (Incidence-rate ratio (IRR) = 0.97; p = 0.021), calcium from milk (IRR = 0.97; p = 0.025) and fermented foods (IRR = 0.96; p = 0.03) were inversely and significantly associated with periodontitis after adjustment for age, gender, education, sucrose intake, alcohol consumption, smoking, physical activity, vitamin D intake, heart disease, visits to the dentist, use of dental floss and bleeding on probing, but non-dairy calcium, calcium from cheese and other types of dairy food intakes were not. Total dairy foods (IRR = 0.96; p = 0.003), milk (IRR = 0.96; p = 0.028) and fermented foods intakes (IRR = 0.97; p = 0.029) were associated with reduced risk of periodontitis, but cheese and other dairy foods intakes were not. These results suggest that dairy calcium, particularly from milk and fermented products, may protect against periodontitis. Prospective studies are required to confirm these findings.     

Antioxidative probiotic fermented goats' milk decreases oxidative stress-mediated atherogenicity in human subjects

The increasing interest in a healthy diet is stimulating innovative development of novel scientific products in the food industry. The viable lactic acid bacteria in fermented milk products, such as yoghurt, have been associated with increased lactose tolerance, a well-balanced intestinal microflora, antimicrobial activity, stimulation of the immune system and antitumoural, anticholesterolaemic and antioxidative properties in human subjects. Recently, we have studied a human Lactobacillus spp. strain that possesses antioxidative activity. The aim of the present pilot study was to develop goats' milk fermented with the human antioxidative lactobacilli strain, Lactobacillus fermentum ME-3, and to test the effect of the fermented probiotic goats' milk on oxidative stress markers (including markers for atherosclerosis) in human blood and urine and on the gut microflora. Twenty-one healthy subjects were assigned to two treatment groups: goats' milk group and fermented goats' milk group (150 g/d) for a period of 21 d. Consumption of fermented goats' milk improved anti-atherogenicity in healthy subjects: it prolonged resistance of the lipoprotein fraction to oxidation, lowered levels of peroxidized lipoproteins, oxidized LDL, 8-isoprostanes and glutathione redox ratio, and enhanced total antioxidative activity. The consumption of fermented goats' milk also altered both the prevalence and proportion of lactic acid bacteria species in the gut microflora of the subjects. We conclude that the goats' milk fermented with our special antioxidative lactobacilli strain Lactobacillus fermentum ME-3 exhibits anti-atherogenic effects.     

Evaluation of immune response,microbiota, and blood markers after probiotic bacteria administration in obese mice induced by a high-fat diet

ObjectiveObesity is associated with alterations in intestinal microbiota and immunity. The aim of this study was to determine the effect of probiotic Lactobacillus casei CRL 431 administration on intestinal and humoral immune response, clinical parameters, and gut microbiota was evaluated using a high-fat diet to induce obesity in a mouse model.MethodsAdult mice received a conventional balanced diet or a high-fat diet supplemented with milk, milk fermented by Lactobacillus casei (FM), L. casei as suspension, or water over 60 d. Histology of liver and small intestine (SI), immunoglobulin A-positive cells and macrophages in SI, phagocytic activity of spleen and peritoneal macrophages, and humoral immune response to ovalbumin were studied. Clinical parameters in serum and gut microbiota were also analyzed.ResultsFM was the most effective supplement for decreasing body weight and clinical parameters in serum. The histology of liver and SI was also improved in obese mice given FM. These animals had increased numbers of immunoglobulin A-positive cells and macrophages in SI. The gut microbiota showed that obese mice given probiotics had increased Bacteroides and bifidobacteria. Administration of FM or L. casei as suspension enhanced the phagocytic activity of macrophages. The anti-ovalbumin specific immune response was not increased by any supplement assayed.ConclusionAdministration of probiotics to obese hosts improved the gut microbiota and the mucosal immunity altered by obesity, down-regulated some biochemical parameters in blood associated with metabolic syndrome, and decreased liver steatosis. These results demonstrate the potential use of probiotics in obese individuals to decrease the body weight and to improve the biochemical and immunologic parameters altered by obesity.     

Characterization of casein phosphopeptides from fermented milk products

This study dealt with the potential of fermented milk products as a source of functional casein phosphopeptides (CPPs) using plain yogurts and Camembert cheeses. The CPPs were prepared by tryptic digestion from four commercially available plain yogurts (P1-P4), five Camembert cheeses (C1-C5), and raw milk. From portions with a 1-g protein content of the plain yogurts, the Camembert cheeses, and the raw milk, 171 mg, 139 mg, and 146 mg of CPPs were obtained, respectively. The Camembert cheeses retained high amounts of organic phosphorus (32 microg) per 1 mg CPPs compared to the raw milk (15 microg) and plain yogurts (16 microg). Reverse-phase high-performance liquid chromatographic analysis showed that the elution patterns and retention times of the three major peaks of CPPs from P1 and C1 were similar to those from raw milk. Moreover, CPPs from P1 and C1 showed a mitogenic effect, while CPPs from C1 showed an IgA-enhancing effect in mouse spleen cell cultures. These results suggest that fermented milk products such as plain yogurts and Camembert cheeses generate functional CPPs in the body and exert beneficial effects on the immune system.     

Analysis of the dependence between milk and dairy products consumption, and dental caries observed in group of children and teenagers

The aim of this research was evaluation of influence of milk and dairy products consumption on advance of dental caries observed in the group of children and teenager. The dependences between milk and dairy products (dairy beverages, cottage cheese and other kinds of cheese) consumption and advance of dental caries were analyzed. The objects of the research were 44 patients aged 7-18 years. Elements of the research were the questionnaire survey and the assessment of the patients diet. The statistical analysis was conducted using the Kolmogorov-Smirnov test and Kruskall-Wallis test as far as the coefficient of correlations by Pearson. In the research it was found that cheese consumption contributes to decrease of dental caries coefficient. The need to provide children and teenagers commonly the nutritional education, concentrating on proper model of the diet and systematic consumption of milk and dairy products, was proved.     

Effect of feeding fermented milk on the incidence of chemically induced colon tumors in rats

The effect of feeding skim milk fermented by Streptococcus thermophilus or Lactobacillus bulgaricus on the incidence of chemically induced colon tumors was studied in rats. Weanling Fisher‐344 rats were fed chow plus skim milk (SM), chow plus SM fermented by S. thermophilus, chow plus SM fermented by L. bulgaricus, or chow plus water until sacrifice at 36 weeks, or before if moribund. Colon tumors were induced by s.c. injections of 1,2‐dimethylhydrazine hydrochloride during weeks 3 through 22. The control (chow + water) group received saline injections. The survival rate of the rats fed fermented milks was significantly higher than that of the rats fed nonfermented milk. The latter had a significantly higher incidence of ear‐duct tumors than the rats receiving fermented milk. The percentage of rats showing colon tumors was similar among all three experimental groups. The control group did not have any tumors. The rats receiving fermented milk had a significantly higher incidence of small‐intestine tumors than those receiving nonfermented milk. The rats on S. thermophilus milk had the lowest percentage of malignant colon tumors of the three experimental groups. Results indicated that the feeding of fermented milks altered the metabolism of 1,2‐dimethylhydrazine and shifted the target organ from the ear duct to the small intestine. In addition, the colon tumor distribution for the fermented‐milk groups appeared to shift toward the anus.     

Effects of milk fermented by Lactobacillus gasseri SBT2055 on adipocyte size in rats

Despite adequate scientific evidence of the potential benefits of probiotics to human health or disease prevention, their contribution to the growth of adipose tissue remains to be established. Four-week-old male Sprague-Dawley rats were fed a diet containing skim milk (control diet) or skim milk fermented by Lactobacillus gasseri SBT2055 (LGSP diet) for 4 weeks. Their body weight gain, adipose tissue weight, adipocyte size distribution profile, blood and hepatic lipids, and serum leptin, glucose and adiponectin levels were determined. There was a significant reduction in average adipocyte size in mesenteric white adipose tissue (P = 0.004). Moreover, the rats fed the LGSP diet displayed greater numbers of small adipocytes from mesenteric and retroperitoneal adipose tissues than did those on the control diet. Whereas adiponectin concentrations did not differ between the groups, serum leptin concentrations were decreased to 32 % in the LGSP diet group compared with the control group. Concentrations of serum glucose and lipids, and liver lipids, except for the liver TAG level, were similar in the two groups. These results indicate a possible role for a fermented milk product in the regulation of adipose tissue growth.     

Milk and dairy consumption and risk of cardiovascular diseases and all-cause mortality: dose–response meta-analysis of prospective cohort studies

With a growing number of prospective cohort studies, an updated dose–response meta-analysis of milk and dairy products with all-cause mortality, coronary heart disease (CHD) or cardiovascular disease (CVD) have been conducted. PubMed, Embase and Scopus were searched for articles published up to September 2016. Random-effect meta-analyses with summarised dose–response data were performed for total (high-fat/low-fat) dairy, milk, fermented dairy, cheese and yogurt. Non-linear associations were investigated using the spine models and heterogeneity by subgroup analyses. A total of 29 cohort studies were available for meta-analysis, with 938,465 participants and 93,158 mortality, 28,419 CHD and 25,416 CVD cases. No associations were found for total (high-fat/low-fat) dairy, and milk with the health outcomes of mortality, CHD or CVD. Inverse associations were found between total fermented dairy (included sour milk products, cheese or yogurt; per 20 g/day) with mortality (RR 0.98, 95% CI 0.97–0.99; I² = 94.4%) and CVD risk (RR 0.98, 95% CI 0.97–0.99; I² = 87.5%). Further analyses of individual fermented dairy of cheese and yogurt showed cheese to have a 2% lower risk of CVD (RR 0.98, 95% CI 0.95–1.00; I² = 82.6%) per 10 g/day, but not yogurt. All of these marginally inverse associations of totally fermented dairy and cheese were attenuated in sensitivity analyses by removing one large Swedish study. This meta-analysis combining data from 29 prospective cohort studies demonstrated neutral associations between dairy products and cardiovascular and all-cause mortality. For future studies it is important to investigate in more detail how dairy products can be replaced by other foods.     

Effects of Lactofermented Beetroot Juice Alone or with N-nitroso-N-methylurea on Selected Metabolic Parameters,Composition of the Microbiota Adhering to the Gut Epithelium and Antioxidant Status of Rats

An objective of this work was to assess the biological activity of beetroot juice (Chrobry variety, Beta vulgaris L. ssp. vulgaris), which was lactofermented by probiotic bacteria Lactobacillus brevis 0944 and Lactobacillus paracasei 0920. The oxidative status of blood serum, kidneys, and liver of rats consuming the fermented beetroot juice were determined. The experimental rats were divided into four groups on diet type: Basal diet, basal diet supplemented with fermented beetroot juice, basal diet and N-nitroso-N-methylurea treatment, and basal diet supplemented with fermented beetroot juice and N-nitroso-N-methylurea treatment. Mutagen N-nitroso-N-methylurea, which was added to diet in order to induce aberrant oxidative and biochemical processes and disadvantageous changes in the count and metabolic activity of the gut epithelium microbiota. The nutritional in vivo study showed that supplementing the diet of the rats with the lactofermented beetroot juice reduced the level of ammonia by 17% in the group treated with N-nitroso-N-methylurea. Furthermore, the positive modulation of the gut microflora and its metabolic activity was observed in groups of rats fed with the diet supplemented with the fermented beetroot juice. A concomitant decrease in the β-glucuronidase activity was a consequence of the gut epithelium microbiota modulation. The antioxidant capacity of blood serum aqueous fraction was increased by about 69% in the group of rats treated N-nitroso-N-methylurea mixed with the fermented beetroot juice and N-nitroso-N-methylurea versus to the N-nitroso-N-methylurea treatment, whereas the antioxidant parameters of the blood serum lipid fraction, kidneys, and liver remained unchanged.     

Different level of conjugated linoleic acid (CLA) in dairy products from Italy

A survey was carried out to determine the content of conjugated linoleic acid (CLA) in various dairy products. The only detected CLA isomer was cis-9trans-11 linoleic acid. Commercial samples of yoghurt, fermented milk and cheese were analyzed: 16 standard yoghurts, 6 organic yoghurts, 8 mountain pasture yoghurts, 5 sheep yoghurts, 8 probiotic yoghurts, 8 fermented milk samples, 6 fermented milk samples from mountain pastures, 30 cow cheeses (9 Alpine cheeses, 8 Swiss Emmental, 8 Fontina Valdostana, 5 Grana Padano and Parmigiano Reggiano), 12 ewe cheeses (Pecorino) and 8 goat cheeses. The fatty acid composition and fat content were also assessed. Fontina Valdostana had the highest amount of CLA (8.11 mg/g fat), followed by Pecorino cheese (7.77 mg/g fat), Swiss Emmental (7.66 mg/g fat) and sheep yoghurt (6.92 mg/g fat). High levels of CLA were also found in fermented milk and yoghurt of mountain pasture and organic yoghurt (6.15, 6.06 and 6.05 mg/g fat, respectively). The animal diet, specific characteristics of the milk used in manufacturing, with special reference to the species and CLA content of the milk, processing and production methods play an important role in setting the CLA levels in dairy products.     

Dairy products and its association with incidence of cardiovascular disease: the Malmö diet and cancer cohort

It is unclear whether specific dairy products are associated with risk of cardiovascular disease (CVD). The aim of this project was therefore to examine the association between intake of milk, cheese, cream and butter, and incidence of CVD in the Swedish Malmö Diet and Cancer cohort. Milk was separated into fermented (yoghurt and cultured sour milk) versus non-fermented milk, and low-fat versus high-fat milk. Among 26,445 individuals without a history of myocardial infarction, stroke and diabetes (44–74 years; 62% females), 2,520 CVD cases (coronary and stroke events) were identified during a mean follow-up time of 12 years. Dietary data was collected using a modified diet history method. Overall consumption of dairy products was inversely associated with risk of CVD (P _trend = 0.05). Among the specific dairy products, a statistically significant inverse relationship was observed only for fermented milk. The highest versus lowest intake category of fermented milk was associated with 15% (95% CI: 5–24%; P _trend = 0.003) decreased incidence of CVD. We observed a statistically significant interaction between sex and cheese intake (P = 0.046). Cheese intake was significantly associated with decreased CVD risk in women (P _trend = 0.03), but not in men (P _trend = 0.98). The main finding was that a high intake of fermented milk may reduce the risk of CVD. This study suggests that it is important to examine dairy products separately when investigating their health effects.     

Lactobacillus casei strain Shirota-fermented milk stimulates indigenous Lactobacilli in the pig intestine

The aim of this study was to determine the effect of a probiotic, i.e. fermented milk prepared with Lactobacillus casei strain Shirota, on indigenous Lactobacilli in the pig large intestine. This fermented milk was given as a probiotic to experimental pigs for 2 weeks. The fecal organic acid concentration increased with the fermented milk; acetate and propionate increased significantly (p<0.05). At the same time, lactate and butyrate tended to increase. The fecal pH was significantly reduced by the fermented milk (p<0.05). Although the number of bacteria of strain Shirota in the intestinal contents was much smaller than those of indigenous Lactobacilli, 10(4) vs 10(8) (cfu/g), the numbers of indigenous Lactobacilli and Bifidobacteria in the pig intestine appeared to increase with the fermented milk. In addition, the phenotypic diversity (phenotypic group numbers) of indigenous Lactobacilli increased from 3 to 8 with the fermented milk supplementation. Thus the fermented milk affected the indigenous Lactobacillus population and constitution.     

长期抗生素暴露对高脂饮食负荷小鼠糖代谢和肠道菌群的影响

目的 探究长期抗生素暴露对高脂饮食负荷小鼠糖代谢和肠道菌群的影响。方法 45只新生BALB/c小鼠随机分为对照组、高脂饮食组和高脂饮食抗生素联合组（n=15）,联合组小鼠出生后以头孢曲松（100mg/kg）灌胃15周,第21d起,高脂组和联合组以高脂饲料,对照组以普通饲料喂养12周。实验结束后,对小鼠进行口服糖耐量实验并采集小鼠内脏、脂肪、血清和粪便,测定小鼠脏器系数、脂体比、血糖、胰岛素和瘦素及肠道菌群。结果 高脂饮食引起小鼠肝脏系数、总脂体比、胰岛素抵抗指数、空腹血糖和血糖曲线下面积显著升高（P均<0.05）。与对照组和高脂组比较,联合组alpha多样性指数显著降低（P<0.05）;主坐标分析显示三组组间群落组成具有明显差异。门水平上,与高脂组比较,联合组厚壁菌门相对丰度显著升高（P<0.05）,拟杆菌门相对丰度显著降低（P<0.05）,高脂组变形菌门相对丰度显著高于对照组和联合组（P均<0.05）。属水平上,高脂饮食诱导厚壁菌门布劳特氏菌属（Blautia）相对丰度增加,降低了拟杆菌门另枝菌属（Alistipes）相对丰度,联合组厚壁菌门肠球菌属（Enterococcus）和葡萄球菌属（Staphylococcus）相对丰度明显升高,其他菌属相对丰度均降低。结论 长期抗生素暴露可能通过改变肠道中细菌生长从而调节肠道菌群,在一定程度上抵抗高脂饮食负荷小鼠的糖代谢失调,表明肠道细菌和宿主代谢功能间存在密切的关联,肠道细菌有望成为改善膳食营养调节的机体能量代谢的重要靶点。