Polyamine is a small organic polycation composed of a hydrocarbon backbone with multiple amino groups which ubiquitously exists in all living organisms from bacteria to higher animals. The critical step of polyamine biosynthesis generally includes the amino acid-decarboxylating reaction to produce the primary diamines, such as a synthesis of putrescine (NH3+·(CH2)4·NH3+) from ornithine, and cadaverine (NH3+·(CH2)5·NH3+) from lysine, which are catalyzed by pyridoxal-5'-phosphate (PLP; vitamin B6)-dependent decarboxylases. Synthesized polyamines are implicated in a wide variety of cytoplasmic reactions such as DNA replication and protein synthesis, and are essential for proper growth of the organisms. However, in Selenomonas ruminantium, a strictly anaerobic Gram-negative bacterium dominant in sheep rumen, cadaverine displays its function in a quite distinctive scheme compared to the general bacteria reported. It serves as an essential constituent of the peptidoglycan for the maintenance of envelope integrity through an interaction with the periplasm-exposed SLH domain of Mep45, the outer membrane protein of this bacterium. Furthermore, cytoplasmic biosynthesis of cadaverine occurs totally in a eukaryotic-like manner rather than in a conventional way of bacteria. Lysine/ornithine decarboxylase (LDC/ODC), a PLP-dependent enzyme responsible for cadaverine synthesis in this bacterium, displays significant homology to the eukaryotic ODC but not to the general bacterial LDC nor ODC, and its activity is tightly regulated by antizyme-mediated proteolysis, a regulatory process generally found in eukaryotes. These findings represent the biological diversity of this bacterium beyond the preexisting knowledge related to the polyamine-physiology, cell envelope-architecture, and the regulatory system for the enzyme. In this review we will describe (i) the cadaverine-containing peptidoglycan of S. ruminantium: its chemical structure, biosynthesis, and biological function, and (ii) cellular biosynthesis of cadaverine by LDC/ODC and its antizyme-mediated regulation. In addition, we will briefly refer to (iii) the phylogenetic position and characteristics of S. ruminantium and its unique cadaverine-physiology.
We aimed to define whether vitamin E improves biochemical indices associated with symptoms of atopic dermatitis-like inflammation in NC/Nga mice. After picryl chloride (PC) application to their backs, changes in the content of thiobarbituric acid reactive substances (TBARS) and vitamin E, as well as the activity of antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GSHPx) and catalase) were analyzed in the serum and skin of NC/Nga mice during a symptomatic cycle. The levels of inflammatory factors were also assessed, including IgE, cyclooxigenase-2 (COX-2), tumor necrosis factor (TNF-α) and nuclear factor-κB (NF-κB). When allergic dermatitis was induced by the application of PC to the skin of the mice, skin inflammation appeared 2 wk after PC application, with the peak severity of inflammation observed 5 wk after PC application. Subsequently, the animals recovered from the inflammation by 9 wk after PC application. The TBARS content in the skin and serum increased markedly when the symptoms were the most severe, and decreased to levels near those in control mice by 9 wk after PC application. The activities of SOD and GSHPx in the skin and serum were also positively correlated with symptomatic changes; however, no change in catalase activity was observed 5 wk after PC application. Conversely, vitamin E content decreased at the stage of peak severity. The levels of all inflammatory factors analyzed in this study were altered in a manner similar to other indices. Additionally, vitamin E treatment markedly inhibited these PC-induced alterations. On the basis of these results, it is expected that the observed alterations in biochemical indices, which reflect the symptomatic cycle, may be applicable to objective diagnosis and treatment for atopic dermatitis, and that vitamin E may improve the symptoms of AD.
Here we quantified ascorbic acid (AA) levels in 14 tissues, plasma and urine of C57BL/6 male mice to track its turnover during 3 to 30 mo of aging. The AA content of adrenal glands and testes decreased somewhat with age, and eventually rose, but increased in the spleen, lungs, eyes and heart. AA levels rose in the liver, skin and skeletal muscles from 6 to 12 mo of age, but declined from 12 to 24 mo. In the cerebellum, cerebrum, small intestine, kidney and plasma, amounts of AA remained almost constant as the animals aged. Most notably, urinary AA decreased markedly until becoming almost undetectable at 24 and 30 mo of age. Collectively, these results, which compare changes in AA levels in specific physiologic targets throughout the aging process, strongly suggest that the AA synthesizing capacity declines over time to become a major factor in senescence-related diseases.
The albedo is the white part of the citrus peel, which acts as a water reservoir for the juice sacs, seeds and leaves in times of drought. As the functionality of the albedo is unknown, we examined in this study the hypolipidemic and bifidogenic potentials of dietary fiber (DF) prepared from the Mikan (Japanese mandarin orange: Citrus unshiu) albedo. The albedo was obtained from Mikan harvested in Arida, Wakayama Prefecture, and total DF (TDF), water soluble DF (SDF) and water insoluble DF (IDF) were extracted. Albedo TDF contained arabinose (37.21%), galactose (16.05%), xylose (18.30%) and glucose (13.94%), but did not contain detectable amounts of galacturonic acid. Albedo SDF inhibited the enzymatic digestion of triolein by pancreatic lipase in vitro. The SDF, at a concentration of 80 mg per 6 mL of substrate solution, significantly inhibited the activity of this enzyme (>50%). As compared to a control group on a 5% cellulose diet, rats fed a diet containing 1% albedo TDF for 4 wk showed significantly decreased serum triacylglycerol concentrations, increased fecal lipid excretion, and no changes in hepatic lipid content (triacylglycerol, total cholesterol, and phospholipid) or serum concentrations of total cholesterol or phospholipid. Consumption of albedo TDF also increased the number of bifidobacteria in the cecum. In this report, we have demonstrated that consumption of albedo TDF increased the levels bifidobacteria in the rat cecum, and decreased serum triacylglycerol concentrations due to the accelerated lipid excretion into the feces caused by the inhibition of pancreatic lipase.
Increased leukocyte counts, particularly white blood cell and neutrophil counts, are reportedly associated with increased incidence of cardiovascular diseases (CVD) and mortality in subjects with acute and moderate coronary diseases. However, few reports have determined the associations between leukocyte subset (i.e., white blood cells, neutrophils, monocytes, lymphocytes, basophils and eosinophils) counts and CVD risk factors. In this study, we examined the associations between leukocyte subset counts and CVD risk factors in apparently healthy Japanese men. We conducted a cross-sectional study of men who participated in health checkups, and selected those who were not being treated for metabolic diseases. We determined associations between leukocyte subset counts and CVD risk factors by multivariate linear regression (MLR) analysis and analysis of covariance (ANCOVA). Overall, 3,576 subjects aged 49.3±5.75 (range, 40-59) y were recruited. MLR and ANCOVA showed that white blood cell, neutrophil, monocyte counts are associated with decreased high-density lipoprotein cholesterol (HDL-C) and increased C-reactive protein levels, the lymphocyte count is positively associated with lipid abnormalities (i.e., decreased HDL-C, increased low-density lipoprotein cholesterol and increased triacylglycerol (TG)), and the basophil count is associated with increased TG and liver injury marker levels (i.e., alanine aminotransferase). Our results in this study demonstrated that leukocyte subset counts showed differential associations with CVD risk factors in apparently healthy Japanese men.
The present study aims to evaluate the anti-HCV activity of hotwater extract from Platycodon grandiflorum (BC703) with HCV genotype 1b subgenomic replicon system and investigate its hepatoprotective activity on carbon tetrachloride (CCl4)-induced acute liver damage in mice. BC703 produced significant hepatoprotective effects against CCl4-induced acute hepatic injury by decreasing the activities of serum enzymes, nitric oxide and lipid peroxidation. Histopathological studies further substantiated the protective effect of BC703. Furthermore, BC703 inhibited the HCV RNA replication with an EC50 value and selective index (CC50/EC50) of 2.82 μg/mL and above 35.46, respectively. However, digested BC703 using a simulated gastric juice showed poor protective effect against CCl4-induced hepatotoxicity in mice and decreased anti-HCV activity as compared to the intact BC703. Although further studies are necessary, BC703 may be a beneficial agent for the management of acute hepatic injury and chronic HCV infection.
The aim of the present study was to investigate the anti-obesity effects of Aloe vera gel administration in male Sprague-Dawley (SD) rats with diet-induced obesity (DIO). SD rats at 7 wk of age were fed either a standard diet (10 kcal% fat) (StdD) or high-fat (60 kcal% fat) diet (HFD) during the experimental period. Four weeks after of HFD-feeding, DIO rats (11 wk of age) were orally administered with two doses of Aloe vera gel powder (20 and 200 mg/kg/d) for 90 d. Body weights (g) and body fat (%) of HFD fed rats were significantly higher than those of StdD-fed rats. Although a modest decrease of body weight (g) was observed with the administration of dried Aloe vera gel powder, both subcutaneous and visceral fat weight (g) and body fat (%) were reduced significantly in Aloe vera gel-treated rats. Serum lipid parameters elevated by HFD were also improved by the Aloe vera gel treatment. The oxygen consumption (VO2), an index of energy expenditure, was decreased in HFD-fed rats compared with that in StdD-fed rats. Administration of Aloe vera gel reversed the change in VO2 in the HFD-fed rats. These results suggest that intake of Aloe vera gel reduced body fat accumulation, in part, by stimulation of energy expenditure. Aloe vera gel might be beneficial for the prevention and improvement of diet-induced obesity.
Puerarin, a daidzein-8-C glucoside, is the major isoflavonoid in Kudzu (Pueraria lobata), and is unique in that it contains C-C conjugated glucose at position 8 of the isoflavonoid structure. A puerarin diet at a dose of 5 mg/kg b.w./d to fed ovariectomized mice for 2 mo diminished the urinary deoxypyridinoline, a typical bone-degradation product. Since the bone absorption marker, serum tartarate-resistant acid phosphatase (TRAP) activity of puerarin-fed mice decreased but the bone formation marker, osteocalcin level, did not alter, the puerarin diet was proved to specifically depress the bone absorption, but not the overall bone metabolism. In accordance with that results, the femur structure of puerarin-fed mice was restored compared with that of puerarin-free diet mice. The atrophied uterine due to low estrogen (E2) level after ovariectomy was not restored by the puerarin diet, suggesting that puerarin exerted the anti-osteoporotic action through a non estrogen receptor (ER) mediated-pathway, in vivo. The growth of an ER-positive human breast cancer cell, MCF-70, was not enhanced by puerarin, suggesting that puerarin did not show estrogen-like action on MCF-7 cells, even at a ten thousand times higher concentration than that of E2. Furthermore, ICI182,780 (ICI), an estrogen antagonist, suppressed the enhanced growth of MCF-7 cells by E2, but not that by puerarin. In an ER-binding assay, puerarin was proved not to bind to ERα or β, or if all, extremely weakly, although daidzein, an aglycon of puerarin, showed a little stronger binding compared with puerarin. All these results strongly indicate that puerarin exerts its anti-osteoprotic action independently of the ER-mediated pathway.
In recent years the occurrence of thiamin deficiency diseases has increased particularly among elderly people and there has been some speculation about whether or not any particular factors exist. In this study, we focused on elderly people requiring constant care in nursing homes and we conducted an accurate condition survey of total thiamin concentration in whole blood as a means of nutritional assessment. The total number of participants was 14 males and 60 females who were residing in a nursing home; they were aged between 65 and 105 y old. All of the subjects agreed to take part in our research. We conducted the following tests: anthropometric measurements, blood examination including total thiamin levels, and also physical functions such as in the level of nursing care required and tests of other physical conditions. The average±standard deviation of thiamin concentration was 22.4±8.9 ng/mL and the number of people with a deficient condition (less than 20 ng/mL) was 42, which was 56.8% of the total. From these results, the existence of thiamin deficiency is validated in more than half of the elderly people who require nursing care. On the other hand, the method of meal intake for all participants who have a thiamin deficiency was oral intake and for those who were non-deficient in thiamin, the percentage of tube feeding or nutritional supplementation intravenously was 37.5%, which was a significantly high value.
Inhibitor activity against digestive enzymes, such as α-amylase from human saliva and porcine pancreas and trypsin from bovine pancreas, of three cereal grains species were studied as potential components of nutraceuticals strengthening diabetes and obesity treatment. Significant differences were demonstrated: the highest antitryptic activity was found in the grain of the rye varieties studied, whereas the grain of the wheat varieties had significantly higher ability to inhibit α-amylases from human saliva and porcine pancreas. Additionally, seeds of Puma, one of the studied wheat varieties, demonstrated especially low antitryptic activity. Such a beneficial arrangement of inhibitors, i.e. high level of inhibitors of α-amylase from human saliva and porcine pancreas and simultaneously low level of trypsin inhibitors from bovine pancreas, indicate the possibility of the application of seeds with such properties to the preparation of nutraceuticals for people with obesity or suffering from diabetes.