SEARCH · PubMed Health

Results for “Lacticaseibacillus casei”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources

PubMed2004

The effect of milk fermented by yogurt cultures plus Lactobacillus casei DN-114001 on the immune response of subjects under academic examination stress.

BACKGROUND: A suppressed immune response has been documented in students under examination stress. AIMS: The current study aimed to evaluate the effect of milk fermented with yogurt cultures plus Lactobacillus casei DN-114001 (Actimel) on the immune system of subjects under academic examination stress. METHODS: University students were allocated to one of two groups, receiving during 6 weeks (3 weeks prior to, as well as the 3-week duration of the examination period) either: a) a glass of semi-skimmed milk each day (control group, n=63) or b) two 100mL portions per day of fermented milk (treatment group, n=73). Anxiety and immunological measurements were monitored at baseline (Phase 0) and study end (Phase 1). RESULTS: The results were expressed as the differences between the data obtained from Phase 0 and Phase 1. This was calculated by subtracting Phase 1 results from the Phase 0 and it is denominated "Treatment effect". Mean (+/- SE) anxiety increased significantly (P<0.05) over the 6-week study in all students, from 40.74+/-2.50 to 61.19+/-2.64 (in percentiles). There was no significant treatment effect since this increase was similar in the control and the treatment groups (21.65+/-5.09 vs 19.14+/-3.67, respectively). However, there was a significant treatment effect (P<0.05) on the mean change in absolute number of lymphocytes during the 6-week study, which decreased in the control group (-0.04+/-0.12 cells x 10(3)/mm(3)) and increased in the treatment group (0.37+/-0.11 cells x 10(3)/mm(3)). There was also a significant treatment effect (P<0.05) on the change in absolute numbers of CD56 cells during the 6-week study. Mean absolute CD56 cells significantly decreased (P<0.05) in the control group (-51.97+/-21.33 cells/mm(3)),while remaining similar in the treatment group (17.29+/-17.27 cells/mm(3)). During the study, mean serum cortisol increased 4.30+/-0.98 microg/dL in the control group, and 1.75+/-1.05 microg/dL in the treatment group and no significant differences were found between both values (P=0.062). CONCLUSIONS: Milk fermented with yogurt cultures plus Lactobacillus casei DN-114001 was able to modulate the number of lymphocytes and CD56 cells in subjects under academic examination stress.

Adolescent↗

PubMed1999

A rapid and safe plasmid isolation method for efficient engineering of recombinant lactobacilli expressing immunogenic or tolerogenic epitopes for oral administration.

Recombinant lactobacilli are being developed which can be used as expression and delivery vectors of heterologous antigens in oral vaccination and other therapeutic applications. Because most Lactobacillus strains do not accept ligation mixtures, sufficiently pure plasmid DNA needs to be isolated from Lactobacillus casei to transform other Lactobacillus strains. The isolation of plasmid DNA from Gram-positive lactobacilli is complicated by the resilience of the peptidoglycan layer. Here a rapid, safe and efficient method is described that combines enzymatic breakdown of the cell wall and purification of the plasmid by commercially available DNA-binding columns. For the lysis-resistant L. casei strain, this method yields high levels of pure plasmid DNA that can be used for common molecular techniques, such as digestion and transformation, with high efficiency.

Administration, Oral↗

PubMed1986

Synthesis and antifolate properties of 5,10-methylenetetrahydro-8,10-dideazaminopterin.

The synthesis of the 5,10-methylene analogue of 5,6,7,8-tetrahydro-8,10-dideazaminopterin, a potential dual inhibitor of dihydrofolate reductase (DHFR) and thymidylate synthase (TS) enzymes, is described. The dimethyl ester of 10-carboxy-4-amino-4-deoxy-8,10-dideazapteroic acid was converted to the tetrahydro derivative by hydrogenation. Thermally induced cyclization of the 10-carbomethoxy and the 5-NH groups afforded the 5,10-carbonyl analogue. Reduction of the lactam with borane readily yielded the key 5,10-methylene-4-amino-4-deoxy-8,10-dideazatetrahydropteroic acid methyl ester. Saponification of the benzoate ester and coupling with L-glutamate concluded the synthesis. The title compound was a modest inhibitor of growth in folate-dependent bacteria. Streptococcus faecium and Lactobacillus casei, but inhibition of DHFR or TS derived from L. casei was poor. The compound was also a weak inhibitor of DHFR derived from L1210 murine leukemia and was a weak inhibitor of L1210 growth in culture.

Aminopterin↗

PubMed1975

Synthesis of a fluorescent derivative of amethopterin,.

Fluorescein isothiocyanate was treated with excess diaminopentane and the remaining unsubstituted amino group of the product was condensed, via a carbodiimide-promoted reaction, with a carboxyl group of amethopterin. The final product, a fluorescent derivative of amethopterin, was isolated by chromatography on AE-cellulose and preparative electrophoresis on polyacrylamide. It was shown to be homogeneous by analytical polyacrylamide electrophoresis and thin-layer chromatography. Proof of structure was provided by elemental analysis, absorbance spectra (at pH 7.0, lambdamax at 495 nm; fluorescence emission at 520 nm), and 1H NMR measurements. The fluorescent derivative of amethopterin inhibited transport of amethopterin into Lactobacillus casei and L1210 cells. It was also a good inhibitor of the L. casei and L1210 dihydrofolate reductases and could be used to provide a fluorescent label for the enzymes during polyacrylamide electrophoresis.

Animals↗

PubMed2006

A new synbiotic, Lactobacillus casei subsp. casei together with dextran, reduces murine and human allergic reaction.

We studied the development of atopic dermatitis-like skin lesions in NC/Nga mice and the allergic symptoms and blood patterns of healthy volunteers during the cedar (Cryptomeria japonica) pollen season in Japan following oral administration of a new synbiotic, Lactobacillus casei subsp. casei together with dextran. The combination of L. casei subsp. casei and dextran significantly decreased clinical skin severity scores and total immunoglobulin E levels in sera of NC/Nga mice that had developed picryl chloride-induced and Dermatophagoides pteronyssinus crude extract-swabbed atopic dermatitis-like skin lesions. During the most common Japanese cedar pollen season, synbiotic L. casei subsp. casei and dextran in humans led to no significant changes in total nasal and ocular symptom scores, in the levels of cedar pollen-specific immunoglobulin E, interferon-gamma and thymus and activation regulated chemokine or in the number of eosinophils in sera, whereas the placebo group showed a tendency for increased levels of cedar pollen-specific immunoglobulin E, thymus and activation regulated chemokine and number of eosinophils, and a decrease in interferon-gamma levels. Thus, the oral administration of synbiotic L. casei subsp. casei together with dextran appears to be an effective supplement for the prevention and treatment of allergic reactions.

Adult↗

PubMed1987

Membrane ATPases and acid tolerance of Actinomyces viscosus and Lactobacillus casei.

Lactobacillus casei ATCC 4646 and Actinomyces viscosus OMZ105E were found to differ markedly in acid tolerance. For example, pH profiles for glycolysis of intact cells in dense suspensions indicated that glycolysis by L. casei had an optimal pH of about 6.0 and that glucose degradation was reduced by 50% at a pH of 4.2. Comparable values for A. viscosus cells were at pHs of about 7.0 and 5.6. The difference in acid tolerance appeared to depend mainly on membrane physiology, and the addition of 40 microM gramicidin to cell suspensions increased the sensitivity of the glycolytic system by as much as 1.5 pH units for L. casei and up to 0.5 pH unit for A. viscosus. L. casei cells were inherently somewhat more resistant to severe acid damage than were A. viscosus cells, in that Mg release from L. casei cells in medium with a pH of 3.0 occurred only after a lag of some 4 h, compared with rapid release from A. viscosus cells. However, the major differences pertinent to the physiology of the organisms appeared to be related to proton-translocating ATPases. Isolated membranes of L. casei had about 3.29 U of ATPase per mg of protein, compared with only about 0.06 U per mg of protein for those of A. viscosus. Moreover, the ATPase of L. casei had a pH optimum for hydrolytic activity of about 5, compared with an optimal pH of about 7 for that of A. viscosus.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinomyces↗

PubMed2001

Enhanced antigen-specific delayed-type hypersensitivity and immunoglobulin G2b responses after oral administration of viable Lactobacillus casei YIT9029 in Wistar and Brown Norway rats.

In this study, the effects of orally administered viable Lactobacillus casei Shirota strain YIT9029 on the immunity parameters of Wistar and Brown Norway rats were examined. For this purpose, we used the Trichinella spiralis host resistance model. Two weeks before and during T. spiralis infection, rats were fed 10(9) viable L. casei bacteria 5 days per week. The T. spiralis-specific delayed-type hypersensitivity (DTH) response was significantly enhanced in both Wistar and Brown Norway rats given L. casei. In both rat strains fed L. casei, serum T. spiralis-specific immunoglobulin G2b (IgG2b) concentrations were also significantly increased. In the model, no significant effects of L. casei on larval counts or inflammatory reactions in the tongue musculature, body weights, or lymphoid organ weights were observed. Serum specific antibody responses, other than IgG2b, were not changed by feeding of L. casei. In contrast to L. casei, it was shown that orally administered Bifidobacterium breve or Bifidobacterium bifidum had no influence on the measured infection and immunity indices in the rat infection model. Since the rat DTH response is considered to be a manifestation of Th1 cell-mediated immunity and the IgG2b isotype has been associated with Th1 activity, it was concluded that Th1 cells could play an active role in the immunomodulatory effects of orally administered L. casei. Furthermore, our data do not indicate that the effect of oral supplementation with L. casei is dependent on the genetic background of the host.

Actinomycetales Infections↗

PubMed2006

Lactobacillus casei prevents the upregulation of ICAM-1 expression and leukocyte recruitment in experimental colitis.

Lactobacillus casei has been shown to attenuate the severity of experimental colitis. The objective of the present study was to determine whether the effects of L. casei on colitis are related to modulation of leukocyte recruitment into the inflamed intestine. Rats with a colonic segment excluded from fecal transit were surgically prepared. The segment was decontaminated with antibiotics and recolonized with normal flora isolated from the inflamed rat colon, associated or not to L. casei. Control and colitic [2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced] animals were studied. Leukocyte-endothelial cell interactions were characterized in the colonic microcirculation by intravital microscopy, and ICAM-1 and VCAM-1 expression was measured by the radiolabeled antibody technique. Compared with the noninflamed colonic segment, induction of colitis by TNBS provoked a marked increase in the number of leukocytes firmly adherent to the venular wall (0.5 +/- 0.1 vs. 2.1 +/- 0.6 leukocytes/100 mum, P < 0.01). Colonization with L. casei significantly reduced the number of adherent leukocytes (1.3 +/- 0.4 leukocytes/100 mum; P < 0.05) but did not affect the increased rolling interactions associated with the induction of colitis. Compared with the noncolitic group, induction of colitis was associated with a marked increase in ICAM-1 expression (117 +/- 4 vs. 180 +/- 3 ng antibody/g tissue) that was abrogated when the colitic segment was colonized by L. casei (117 +/- 3 ng antibody/g tissue, P < 0.05). However, L. casei administration did not modify VCAM-1 upregulation in colitic animals. L. casei attenuates leukocyte recruitment observed in experimental colitis induced by TNBS. This effect is possibly related to abrogation of ICAM-1 upregulation.

Animals↗

PubMed1988

Systemic augmentation of the immune response in mice by feeding fermented milks with Lactobacillus casei and Lactobacillus acidophilus.

This study investigates the effect of feeding fermented milks with Lactobacillus casei, Lactobacillus acidophilus and a mixture of both micro-organisms on the specific and non-specific host defence mechanisms in Swiss mice. Animals fed with fermented milk for 8 days (100 micrograms/day) showed an increase in both phagocytic and lymphocytic activity. This activation of the immune system began on the 3rd day, reached a maximum on the 5th, and decreased slightly on the 8th day of feeding. In the 8-day treated mice, boosted with a single dose (100 micrograms) on the 11th day, the immune response increased further. The feeding with fermented milk produced neither hepatomegaly nor splenomegaly. These results suggest that L. casei and L. acidophilus, associated with intestinal mucosae, can influence the level of activation of the immune system. The possible clinical application of fermented milks as immunopotentiators is also discussed.

Animals↗

PubMed1998

The effect of lactic acid bacteria on intestinal metabolism and metabolic profile in gnotobiotic pigs.

The effect of inoculation of Lactobacillus casei on selected parameters of metabolic profile and intestinal metabolism of gnotobiotic piglets was investigated during the first three weeks of their life. The experiment was carried out on 8 germ-free piglets. The experimental group was inoculated once a day with the Lactobacillus casei subsp. casei strain. The inoculum contained 1 x 10(8) microorganisms in 1 ml. The control group of piglets received no inoculum. Lactobacillus casei colonized jejunum and ileum in the numbers from 5.63 to 6.06 log 10 cm-2 and their numbers in the jejunal and ileal contents were in the range 8.38-9.87 log 10.ml-1. The daily consumption of milk by the inoculated animals was significantly higher (p < 0.001). The average weight of inoculated piglets at the end of the period investigated was higher by 29.7%. Lactobacillus casei affected several parameters investigated. Piglets inoculated with lactobacilli showed significantly lower (p < 0.05-0.01) values of pH of the jejunal content, numbers of erythrocytes, values of haematocrit, urea, glucose, total lipids, cholesterol and calcium in the serum and significantly higher values (p < 0.05-0.01) of lactic acid in the jejunal content. The values of phagocytic activity and the index of phagocytic activity in the piglets of the experimental group were two to three-fold higher in comparison with those detected in the control group. The application of Lactobacillus casei affected positively the growth of gnotobiotic piglets, their intestinal metabolism, the level of cholesterol in the serum and phagocytic activity.

Animals↗

PubMed1990

A novel method of preparing totally alpha-deuterated amino acids for selective incorporation into proteins. Application to assignment of 1H resonances of valine residues in dihydrofolate reductase.

The pyridoxal/2H2O exchange reaction of the alpha-CH of amino acids is known to be accompanied by racemisation: Thus by using a D-amino acid as the starting material any L-amino acid formed in the reaction will be essentially fully deuterated at its alpha-position. We have used this method to prepare alpha-deuterated L-valine and incorporated this biosynthetically into L. casei dihydrofolate reductase. A comparison of the alpha CH-NH fingerprint regions of COSY spectra of deuterated and normal DHFR complexes allows one to identify cross-peaks from 15 of the 16 valine residues.

Amino Acids↗

PubMed2006

Effect of orally administered Lactobacillus casei on porcine reproductive and respiratory syndrome (PRRS) virus vaccination in pigs.

The purpose of this study was to determine whether intranasal/oral administration of probiotics can assist vaccination efficacy against an important swine pathogen, porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV). A controlled challenge trial was performed employing: (a) pigs vaccinated against PRRS and treated with a Lactobacillus casei, (b) pigs vaccinated against PRRS only, (c) pigs treated with L. casei only, and (d) pigs neither vaccinated against PRRS nor treated with L. casei. All pigs were challenged intranasally with a wild PRRSV strain. There was no difference in clinical signs or rectal temperature among the four groups. However, pigs that received L. casei gained significantly more weight than pigs that did not. Vaccinated pigs did not gain more weight than nonvaccinated pigs. Vaccinated groups had significantly fewer viraemic pigs on days post-challenge 4, 11 and 17 than nonvaccinated groups of pigs. There was no effect of probiotic on prevalence or duration of viraemia. Among viraemic pigs, there was no significant difference in mean log base(10) titer of PRRS virus among groups. These results suggest that orally administered L. casei does not affect immune response in such a way as to affect PRRS viraemia or nasal shedding. However, it still appears to provide significant benefit when administered during vaccination as indicated by the higher bodyweight gain following PRRS virus infection.

Administration, Intranasal↗

PubMed1990

Nucleotide sequences and genomic constitution of five tryptophan genes of Lactobacillus casei.

Five trp genes, trpD, trpC, trpF, trpB, and trpA, of Lactobacillus casei were cloned by transformation of tryptophan auxotrophic mutants of the respective trp genes in Escherichia coli. These trp genes appear to constitute an operon and are located in the above order in a segment of DNA of 6,468 base pairs. The entire nucleotide sequence of this DNA segment was determined. Five contiguous open reading frames in this segment can encode proteins consisting of 341, 260, 199, 406, and 266 amino acids, respectively, in the same direction. The amino acid sequences of these proteins exhibit 25.5-50.2% homology with the amino acid sequences of the corresponding trp enzymes of E. coli. Two trp genes, trpC and trpF, from L. casei can complement mutant alleles of the corresponding genes of E. coli. However, neither the trpA gene nor the trpB gene of L. casei can complement mutations in the E. coli trpA gene and the trpB gene, respectively, suggesting that the protein products of the L. casei and E. coli trpA and trpB genes, respectively, cannot form heterodimers of tryptophan synthetase with activity. Other features of the coding and flanking regions of the trp genes are also described.

Amino Acid Sequence↗

PubMed2003

Significant differences between Lactobacillus casei subsp. casei ATCC 393T and a commonly used plasmid-cured derivative revealed by a polyphasic study.

Many studies on Lactobacillus casei subsp. casei (L. casei) have been carried out using strain ATCC 393 (pLZ15-). Four strains of L. casei ATCC 393T and three of ATCC 393 (pLZ15-) were compared using phenotypic methods and many of the available genotyping techniques. These tests showed that strains of ATCC 393T obtained from independent public type-culture collections were significantly different from the plasmid-free (pLZ15-) strains of ATCC 393T. These findings were confirmed by sequencing the first 580 nt (domain I) of the 16S and 23S rDNAs of the strains. Complete sequencing of the 16S rDNA of one representative strain from each group revealed that strain ATCC 393T from culture collections was 99% similar to Lactobacillus zeae ATCC 15820T and that the strain so far considered as L. casei ATCC 393 (pLZ15-) was, in turn, 100% similar to L. casei ATCC 334 and Lactobacillus paracasei subsp. paracasei ATCC 4022. All data obtained in this work indicate that the ancestral strain of ATCC 393 (pLZ15-) might never have been the strain that is now available from culture collections.

Base Sequence↗

PubMed1978

Folate status during long-term therapy with trimethoprim and sulphadiazine.

It was studied whether treatment with sulphadiazine and trimethoprim for 8 weeks affected the folate status. The therapy did not inhibit the absorption as assessed by the 3H--folic acid absorption (TRIFA) test. Plasma folic acid clearance showed that folate deficiency had not developed. Bone marrow studies revealed that the antifolic action of the drugs did not manifest itself at the cellular level. The Lactobacillus casei method should not be employed in the determinations of the serum folate concentration during the treatment because therapeutic plasma concentrations of the two drugs inhibit the growth of the test bacteria.

Adult↗

PubMed1994

Non-immunologically-mediated cytotoxicity of Lactobacillus casei and its derivative peptidoglycan against tumor cell lines.

Lactobacillus casei, which shows antitumoral activity mediated by the stimulation of cellular defence mechanisms, and its peptidoglycan were tested for their ability to inhibit in vitro the viability of various murine (Yac-1, P815, Ehrlich ascites tumor, mammary carcinoma) and human (K562, KB) tumor cell lines through primary cytotoxic activity. Treatment of these tumor line with L. casei or its peptidoglycan at different doses and for different times demonstrated a decrease in viability by 25-30%. This cytotoxic activity was revealed by 51Cr release, succinate dehydrogenase (SDH) activity, ATP assays and morphological alterations in the treated tumor cells. Immunoenzymatic assays (ELISA) showed a precise ratio of binding between Ehrlich ascites or YAC-1 cell membranes and peptidoglycan. This binding is discussed with regard to the structure of the peptidoglycan molecule. The results suggest that L. casei and its derivative peptidoglycan have both a stimulating activity in normal cells and an inhibiting activity in tumor cells, as has been found for other immunomodulatory complexes.

Adenosine Triphosphate↗

PubMed1989

Folate analogues. 31. Synthesis of the reduced derivatives of 11-deazahomofolic acid, 10-methyl-11-deazahomofolic acid, and their evaluation as inhibitors of glycinamide ribonucleotide formyltransferase.

The Boon-Leigh procedure, involving condensation of a 6-chloro-5-nitropyrimidine (22) with an alpha-amino ketone (20 or 21) followed by reduction of the nitro group, cyclization, and L-glutamylation, led to the formation of 11-deazahomofolate (29) and its 10-methyl derivative (30). The corresponding (6R,S)-5,6,7,8-tetrahydro (4, 5) and 7,8-dihydro (31, 32) derivatives were prepared by catalytic hydrogenation. (6S)-11-Deazatetrahydrohomofolate was prepared from 29 by enzymatic reduction. Compounds 29 and 30 had little effect (IC50 greater than 2 x 10(-5) M) on Lactobacillus casei glycinamide ribonucleotide (GAR) formyltransferase but (6R,S)-11-deazatetrahydrohomofolate (4) is a potent inhibitor of this enzyme (IC50 = 5 x 10(-8) M). It is at least 100 times more inhibitory than 33, the 6S compound, indicating that the 6R component of the mixture having the unnatural configuration at C6 (34) is responsible for the potent inhibition. Compound 4 is a much weaker inhibitor of murine (L1210) and human (MOLT-4) leukemia cell GAR formyltransferases (IC50 greater than 1 x 10(-5) M). (6R,S)-11-Deaza-10-methyltetrahydrohomofolate (5) (IC50 = 1.1 x 10(-5) is 200 times weaker than 4 against L. casei GAR formyltransferase. However, 11-deaza-10-methyldihydrohomofolate (32) is more inhibitory (IC50 = 5.5 x 10(-7) M) than 5 or 30. None of the compounds showed inhibition of L. casei aminoimidazolecarboxamide ribonucleotide (AICAR) formyltransferase, dihydrofolate reductase, or thymidylate synthase. The dihydro derivatives 31 and 32 are 5% as active as dihydrofolate as substrates for L. casei dihydrofolate reductase. Compound 4 showed moderate inhibition of the growth of L. casei, Streptococcus faecium, MOLT-4 cells, and MCF-7 human breast adenocarcinoma cells.

Acyltransferases↗

PubMed1996

The effect of Lactobacillus GG on the initiation and promotion of DMH-induced intestinal tumors in the rat.

Male Fischer 344 rats were fed a 20% or a 5% corn oil diet and were injected subcutaneously with dimethylhydrazine (DMH) weekly for 16 weeks. In addition, an approximately equal number of animals challenged with DMH were fed daily, until the end of the study, 2 x 10(10) Lactobacillus casei subsp. rhamnosus strain GG starting three weeks before DMH administration or after the ninth weekly injection. The feeding of the Lactobacillus GG before and during carcinogen treatment resulted in a significant decrease in the incidence of colon tumors and the number of small intestinal and colon tumors per tumor-bearing animal for rats fed a 20% corn oil diet. This decrease in tumor incidence or number of tumors was not seen when animals were fed the Lactobacillus after the ninth week of carcinogen treatment. Animals fed a 5% corn oil diet had a lower tumor incidence and number of tumors resulting from the decrease in dietary fat; in addition the feeding of Lactobacillus GG before the carcinogen challenge resulted in a lower incidence of colon tumors. These studies show that a specific strain of L. casei subsp. rhamnosus designated GG can interfere with the initiation or early promotional stages of DMH-induced intestinal tumorigenesis, and this effect is most pronounced for animals fed a high-fat diet.

Animals↗