Daily intake of fermented milk with Lactobacillus casei strain Shirota reduces the incidence and duration of upper respiratory tract infections in healthy middle-aged office workers.

PURPOSE: Although several studies have demonstrated the efficacy of probiotics for preventing upper respiratory tract infections (URTIs) in at-risk populations, including children and the elderly, few studies have investigated the efficacy of probiotics in healthy adults living normal, everyday lives. Thus, we tried to evaluate the effects of Lactobacillus casei strain Shirota-fermented milk (LcS-FM) on the incidence of URTIs in healthy middle-aged office workers. METHODS: In a randomized controlled trial, 96 eligible male workers aged 30-49 years consumed LcS-FM containing 1.0 × 1011 viable LcS cells or control milk (CM) once daily for 12 weeks during the winter season. URTI episodes were evaluated by a physician via a questionnaire of URTI symptoms. RESULTS: The incidence of URTIs during the intervention period was significantly lower in the LcS-FM group than in the CM group (22.4 vs. 53.2 %, P = 0.002). The time-to-event analysis showed that the LcS-FM group had a significantly higher URTI-free rate than the CM group over the test period (log-rank test: χ 2 11.25, P = 0.0008). The cumulative number of URTI episodes and cumulative days with URTI symptoms per person was lower in the LcS-FM group, and the duration per episode was shorter. Inhibition of both reductions in NK cell activity in peripheral blood mononuclear cells and increases in salivary cortisol levels was observed in the LcS-FM group. CONCLUSION: The results suggest that the daily intake of fermented milk with LcS may reduce the risk of URTIs in healthy middle-aged office workers, probably through modulation of the immune system.

Oral Administration of Fermented Soymilk Products Protects the Skin of Hairless Mice against Ultraviolet Damage.

The protective effect of isoflavones on skin damage from ultraviolet (UV) radiation and their bioavailability were investigated in ovariectomized hairless mice fed diets composed of fermented soymilk containing aglycone forms of isoflavones or control soymilk containing glucose-conjugated forms of isoflavones. The erythema intensity of dorsal skin was significantly higher in ovariectomized mice than in sham-operated mice (p < 0.05). The erythema intensity and epidermal thickness of dorsal skin were significantly lower in the fermented soymilk diet group than in the control diet group (each p < 0.05). Levels of cyclobutane pyrimidine dimers in dorsal skin were significantly lower in the fermented soymilk diet group than in the control group (p < 0.05). Serum and dorsal skin isoflavone concentrations were significantly higher in the fermented soymilk diet group than in the soymilk diet group (p < 0.05). These results indicate that oral administration of a fermented soymilk diet increases isoflavone concentrations in the blood and skin, effectively scavenging the reactive oxygen species generated by UV irradiation and exerting an estrogen-like activity, with a consequent protective effect on skin photodamage in hairless mice.

Effect of consuming a purple-fleshed sweet potato beverage on health-related biomarkers and safety parameters in Caucasian subjects with elevated levels of blood pressure and liver function biomarkers: a 4-week, open-label, non-comparative trial.

An open-label study with one treatment arm was conducted to investigate changes in health-related biomarkers (blood pressure and liver enzyme activity) and the safety of 4 weeks of consuming a purple-fleshed sweet potato beverage in Caucasian subjects. Twenty healthy adults, 18-70 years of age, with a body mass index >25 kg/m(2), elevated blood pressure and elevated levels of liver function biomarkers consumed two cartons of purple-fleshed sweet potato beverage (125 ml, including 117 mg anthocyanin per carton) daily for 4 weeks. Hematology, serum clinical profile, dipstick urinalysis and blood pressure were determined before consumption, at 2 and 4 weeks of consumption and after a 2-week washout period. A trend was found toward lowering systolic blood pressure during the treatment period (p=0.0590). No significant changes were found in diastolic blood pressure throughout the study period. Systolic blood pressure was significantly lower after 4 weeks of consumption compared with before consumption (p=0.0125) and was significantly higher after the 2-week washout period compared with after consumption (p=0.0496). The serum alanine aminotransferase level significantly increased over time, but aspartate aminotransferase and γ-glutamyltransferase levels stayed within the normal range of reference values. Safety parameters of the blood and urine showed no clinically relevant changes. The consumption of a purple-fleshed sweet potato beverage for 4 weeks resulted in no clinically relevant changes in safety parameters of the blood and urine and showed a trend toward lowering systolic blood pressure.

Beneficial Effects of Citrus Juice Fermented with Lactobacillus plantarum YIT 0132 on Japanese Cedar Pollinosis.

Recently, the prevalence of allergies in Japan has been increasing. Certain types of fruit juice and lactic acid bacteria are known to alleviate allergic symptoms. Therefore, we examined whether citrus juice fermented by a specific lactic acid bacteria can improve the symptoms of Japanese cedar pollinosis (JCPsis). Lactobacillus plantarum YIT 0132 (LP0132) was selected based on its high proliferative activity in citrus juice and anti-inflammatory interleukin-10-inducing activity. Dietary administration of heat-killed LP0132 cells or citrus juice fermented with LP0132 was found to significantly suppress nasal rubbing in a JCPsis mouse model, indicating relief of allergy symptoms. To evaluate the effects of LP0132-fermented citrus juice on pollinosis symptoms and quality of life (QOL) in humans with JCPsis, a single-blind, placebo-controlled, parallel-group clinical trial was conducted. The participants were 42 adults with JCPsis. They ingested 100 mL of sterilized LP0132-fermented citrus juice (active group) or unfermented citrus juice (placebo group) once daily for 8 weeks. Immediately after the pollen peak when allergy symptoms and QOL loss were most severe, itchy eyes, itchy skin, and QOL loss by JCPsis were alleviated in the active group compared with the placebo group. At 10 weeks after starting the intervention, increased the levels of blood eosinophils were significantly suppressed in the active group compared with the placebo group. We conclude that continuous ingestion of citrus juice fermented with LP0132 may help alleviate the allergy symptoms and impaired QOL caused by JCPsis.

Lactobacillus casei Shirota enhances the preventive efficacy of soymilk in chemically induced breast cancer.

Soy foods are known to be effective for breast cancer prevention. The habitual consumption of soy isoflavones in combination with the probiotic Lactobacillus casei Shirota (LcS) was shown to decrease the risk of breast cancer occurrence in our previous population-based case-controlled study among Japanese women. The present study aimed to elucidate the cooperative prevention mechanism of soymilk and LcS using an animal carcinogenic model. Female Sprague-Dawley rats received a high-fat, AIN-76A diet containing soymilk, LcS, both soymilk and LcS, or none and were orally exposed to 2-amino-1-methyl-6-penylimidazo[4,5-b]pyridine at a dose of 85 mg/kg bodyweight eight times for 2 weeks. The development of palpable mammary tumors was monitored for 17 weeks. Tumor tissues were immunohistochemically examined for estrogen receptor (ER)-α, Ki-67 and CD34. Compared with the control group, the incidence and multiplicity of mammary tumors were reduced by soymilk alone and soymilk in combination with LcS, while tumor volume was decreased by LcS alone and LcS in combination with soymilk. An immunohistochemical analysis revealed that soymilk in combination with LcS more effectively reduced the numbers of ER-α-positive and Ki-67-positive cells in tumors than soymilk alone and that both soymilk and LcS inhibited tumor angiogenesis. These results demonstrated that soymilk prevents the development of mammary tumors and that LcS suppresses tumor growth, potentially enhancing the preventive efficacy of soymilk. The habitual consumption of LcS in combination with soymilk might be a beneficial dietary style for breast cancer prevention.

A high-fat diet and multiple administration of carbon tetrachloride induces liver injury and pathological features associated with non-alcoholic steatohepatitis in mice.

The aim of the present study was to establish a progressive steatohepatitis mouse model because few reported animal models of non-alcoholic steatohepatitis (NASH) show the progression from fatty liver to steatohepatitis. C57BL/6N mice were fed a high-fat diet (HFD) to develop obesity and were either administered carbon tetrachloride (CCl4 ) eight times (0.05 mL/kg, s.c., once, followed by 0.1 mL/kg, s.c., seven times) or not. Serum parameters and hepatic histopathology were examined. In a separate experiment, CCl4 was administered subcutaneously from 0 to eight times to HFD-fed obese mice to investigate progressive changes. Markers of oxidative stress, inflammation and apoptosis, as well as histopathological changes in the liver, were analysed. The HFD-fed obese mice showed fatty liver but not steatohepatitis. In contrast, HFD-fed mice administered CCl4 eight times showed histopathological features of steatohepatitis (fatty liver, inflammation, hepatocellular ballooning and fibrosis) and increased serum alanine aminotransferase levels. However, the multiple administration of CCl4 to obese mice reduced the ratio of reduced glutathione to oxidized glutathione, superoxide dismutase activity and mitochondrial DNA copy number, leading to the development of chronic oxidative stress, increased numbers of apoptotic cells and increased levels of both tumour necrosis factor-α and transforming growth factor-ß mRNA. The resulting inflammation led to increased hydroxyproline content in the liver and fibrosis. The present study demonstrates that multiple administration of CCl4 to HFD-fed obese mice induces chronic oxidative stress that triggers inflammation and apoptosis and leads to the development of fibrosis in the liver, resulting in progression from fatty liver to steatohepatitis. This murine model will be useful in the research of hepatic disorders.

Consecutive Intake of Fermented Milk Containing Bifidobacterium breve Strain Yakult and Galacto-oligosaccharides Benefits Skin Condition in Healthy Adult Women.

A double-blind, placebo-controlled, randomized trial was conducted to investigate the beneficial effect of probiotic and prebiotic fermented milk on the skin of healthy adult women. Forty healthy Japanese adult female volunteers with healthy skin randomly received either a bottle of probiotic and prebiotic fermented milk containing Bifidobacterium breve strain Yakult and galacto-oligosaccharides (GOS) (active group) or a non-fermented placebo milk containing neither probiotics nor GOS (placebo group) daily for 4 weeks. Before and after intake, hydration levels and cathepsin L-like activity in the stratum corneum and phenol levels in the serum and urine were determined. After intake, the hydration level of the stratum corneum decreased significantly in only the placebo group and was significantly lower than in the active group (p=0.031). Cathepsin L-like activity, an indicator of keratinocyte differentiation, was significantly increased in the active group (p=0.027). Serum and urine phenol levels decreased significantly in the active group (p=0.014, p=0.002, respectively), and serum phenol levels were significantly lower in the active group compared with the placebo group (p=0.006). The consecutive intake of probiotic and prebiotic fermented milk can benefit skin condition without dryness and decrease the levels of phenol production by gut bacteria in healthy adult women.

Photoprotective effects of Bifidobacterium breve supplementation against skin damage induced by ultraviolet irradiation in hairless mice.

BACKGROUND: Probiotics have been considered to affect not only the gut but also the skin. This study aimed at examining whether oral administration of live Bifidobacterium breve strain Yakult (BBY), a typical probiotic, could exert photoprotective effects in hairless mouse skin. METHODS: BBY cell suspensions and fermented milk containing BBY (BBYM) were orally administered to hairless mice for 9 and 14 days, respectively. Mice were irradiated with ultraviolet (UV) light daily for the last four consecutive days. Twenty-four hours after the final irradiation, skin elasticity, appearance, elastase activity and interleukin (IL)-1ß levels were evaluated in the dorsal skin. RESULTS: BBY and BBYM significantly prevented UV-induced deleterious changes in skin elasticity and appearance. BBY suppressed the increases in both elastase activity and IL-1ß levels in the skin. There was a significant negative correlation between elastase activity and the ratio of elastic recovery to total deformation and a significant positive correlation between elastase activity and the area ratio of furrows, independent of UV irradiation or BBY administration. CONCLUSION: Our findings suggest that oral administration of probiotic BBY has the potential to prevent UV-induced skin damage, supporting the hypothesis that probiotics are beneficial not only to the intestine but also to the skin.

Anthocyanins from purple sweet potato Ipomoea batatas cultivar Ayamurasaki suppress the development of atherosclerotic lesions and both enhancements of oxidative stress and soluble vascular cell adhesion molecule-1 in apolipoprotein E-deficient mice.

We evaluated the protective potential of anthocyanins from purple sweet potato Ipomoea batatas cultivar Ayamurasaki (APSP) against low-density lipoprotein (LDL) oxidation in vitro and atherosclerotic lesion development in apolipoprotein E-deficient mice given a cholesterol- and fat-enriched diet with or without 1% APSP for 4 weeks. APSP protected LDL against oxidation more potently than other anthocyanins and l-ascorbic acid in vitro. In mice, APSP significantly lowered the atherosclerotic plaque area to about half of the control, the liver level of thiobarbituric acid-reactive substances as an oxidative stress marker, and the plasma level of soluble vascular cell adhesion molecule-1 (sVCAM-1). However, APSP showed no effects on body weight and cholesterol and lipid levels in the plasma. The results suggest that APSP can suppress the development of atherosclerotic lesions and both enhancements of oxidative stress and sVCAM-1 independently of the changes in cholesterol and lipid levels in mice.

Bioavailability of isoflavones after ingestion of soy beverages in healthy adults.

It is unknown whether the bioavailability of isoflavones is affected by the concomitant ingestion of glucosides or aglycones. This study was designed to investigate the effects of soymilk-based beverages containing different types of isoflavones on their absorption, excretion, and metabolism. Twelve healthy volunteers consumed 3 kinds of soymilk: untreated soymilk, beta-glucosidase-treated soymilk, and fermented soymilk. Blood samples were collected after 0, 1, 2, 3, 4, 5, 6, 7, 8, and 24 h. Urine samples were collected from 0 to 48 h. Concentrations of isoflavones and daidzein metabolites in serum and urine were measured by liquid chromatography-mass spectrometry. After the ingestion of soymilk, the total concentration of isoflavones in serum rose slowly and reached a maximum of 0.94 +/- 0.39 micromol/L at 6.0 +/- 1.2 h. However, beta-glucosidase-treated soymilk and fermented soymilk increased the serum isoflavone concentration significantly more quickly with maximum concentrations at 1.0 h of 1.75 +/- 0.33 micromol/L and 2.05 +/- 0.32 micromol/L, respectively. The urinary excretion of isoflavones after ingesting of these aglycone-enriched preparations was significantly greater than after consumption of untreated soymilk up to 8 h after injection, but not thereafter. The total and individual concentrations of isoflavones in serum and urine did not differ when subjects consumed the 2 aglycone-enriched soymilks. However, in equol producers (n = 5), the ingestion of ESM tended to increase urinary excretion of equol compared with the consumption of FSM (P = 0.08). These results demonstrated that the isoflavone aglycones of soymilk were absorbed faster and in greater amounts than their glucosides in healthy adults and that the metabolism of isoflavones might be affected by the type of soymilk consumed.

Antioxidative activity of anthocyanins from purple sweet potato, Ipomoera batatas cultivar Ayamurasaki.

We evaluated the antioxidative activity of anthocyanins from an extract of the tuber of purple sweet potato (PSP) (Ipomoea batatas cultivar Ayamurasaki). Anthocyanins from PSP showed stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity than anthocyanins from red cabbage, grape skin, elderberry, or purple corn, and eight major components of the anthocyanins from PSP showed higher levels of activity than ascorbic acid. In PSP anthocyanin-injected rats and PSP beverage-administered volunteers, DPPH radical-scavenging activity in the urine increased. The elevation of plasma transaminase activities induced by carbon tetrachloride was depressed in rats administered PSP anthocyanin solution. Two components, cyanidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranocyl)-beta-D-glucopyranoide)-5-O-beta-D-glucopyranoside and peonidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranocyl)-beta-D-glucopyranoide)-5-O-beta-D-glucopyranoside, which were detected in the plasma, protected low density lipoprotein from oxidation at a physiological concentration. These results indicate that PSP anthocyanins have antioxidative activity in vivo as well as in vitro.

Cloning of Mongolian gerbil cDNAs encoding inflammatory proteins, and their expression in glandular stomach during H. pylori infection.

Mongolian gerbils are considered to be a good animal model for understanding the development of Helicobacter pylori-associated diseases. However, limitations regarding the genetic information available for this animal species hamper the elucidation of underlying mechanisms. Thus, we have focused on identifying the nucleotide sequences of cDNAs encoding Mongolian gerbil inflammatory proteins, such as interleukin-1 (IL-1beta), tumor necrosis factor alpha (TNF-alpha), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Furthermore, we examined the mRNA expression of these genes in the glandular stomach by RT-PCR at 1-8 weeks after H. pylori infection. The deduced amino acid homologies to mouse, rat and human proteins were 86.2%, 83.6% and 67.8% for IL-1beta, 87.2%, 85.1% and 78.4% for TNF-alpha , 91.9%, 90.2% and 84.8% for COX-2 and 90.8%, 89.1% and 80.1% for iNOS, respectively. The average stomach weight of Mongolian gerbils inoculated with H. pylori was increased in a time-dependent manner at 1, 2, 4 and 8 weeks after inoculation. In the pyloric region, mRNA expression levels of IL-1beta, TNF-alpha and iNOS were increased in H. pylori-infected animals at the 2 weeks time point, while in the fundic region, expression levels of IL-1beta, TNF-alpha and iNOS were elevated at 4 and 8 weeks. The COX-2 expression level in the fundic region was clearly elevated in infected animals compared with control animals at 4 and 8 weeks, but in the pyloric region, expression levels were similar in both infected and control animals. Thus, our results indicate that oxidative stress occurs from an early stage of H. pylori infection in the glandular stomach of Mongolian gerbils.

Absorption of acylated anthocyanins in rats and humans after ingesting an extract of Ipomoea batatas purple sweet potato tuber.

We evaluated the absorbability of anthocyanins in humans and rats administered with a beverage prepared from an extract of the tuber of purple sweet potato (Ipomoea batatas Cultivar Ayamurasaki), or with an anthocyanin concentrate. Two major anthocyanin components, cyanidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside) and peonidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside), were detected in the plasma and urine of both rats and humans by HPLC or liquid chromatography/mass spectrometry (LC/MS). The plasma concentration of anthocyanins in humans reached a maximum 90 minutes after ingestion, and the recovery of anthocyanins in the urine was estimated as 0.01-0.03%. These results indicate that acylated anthocyanins could be selectively absorbed after ingesting food.

Suppression of Helicobacter pylori-induced gastritis by green tea extract in Mongolian gerbils.

Since urease of Helicobacter pylori is essential for its colonization, we focused attention on foodstuffs which inhibit the activity of this enzyme. Among plant-derived 77 foodstuff samples tested, some tea and rosemary extracts were found to clearly inhibit H. pylori urease in vitro. In particular, green tea extract (GTE) showed the strongest inhibition of H. pylori urease, with an IC(50) value of 13 microg/ml. Active principles were identified to be catechins, the hydroxyl group of 5(')-position appearing important for urease inhibition. Furthermore, when H. pylori-inoculated Mongolian gerbils were given GTE in drinking water at the concentrations of 500, 1000, and 2000 ppm for 6 weeks, gastritis and the prevalence of H. pylori-infected animals were suppressed in a dose-dependent manner. Since the acquisition by H. pylori of resistance to antibiotics has become a serious problem, tea and tea catechins may be very safe resources to control H. pylori-associated gastroduodenal diseases.