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1.
bioRxiv ; 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37745384

ABSTRACT

Following peripheral nerve injury, denervated tissues can be reinnervated via regeneration of injured neurons or via collateral sprouting of neighboring uninjured afferents into the denervated territory. While there has been substantial focus on mechanisms underlying regeneration, collateral sprouting has received relatively less attention. In this study, we used immunohistochemistry and genetic neuronal labeling to define the subtype specificity of sprouting-mediated reinnervation of plantar hind paw skin in the mouse spared nerve injury (SNI) model, in which productive regeneration cannot occur. Following an initial loss of cutaneous afferents in the tibial nerve territory, we observed progressive centripetal reinnervation by multiple subtypes of neighboring uninjured fibers into denervated glabrous and hairy plantar skin. In addition to dermal reinnervation, CGRP-expressing peptidergic fibers slowly but continuously repopulated the denervated epidermis, Interestingly, GFRα2-expressing nonpeptidergic fibers exhibited a transient burst of epidermal reinnervation, followed by trend towards regression. Presumptive sympathetic nerve fibers also sprouted into the denervated territory, as did a population of myelinated TrkC lineage fibers, though the latter did so less efficiently. Conversely, rapidly adapting Aß fiber and C fiber low threshold mechanoreceptor (LTMR) subtypes failed to exhibit convincing collateral sprouting up to 8 weeks after nerve injury. Optogenetics and behavioral assays further demonstrated the functionality of collaterally sprouted fibers in hairy plantar skin with restoration of punctate mechanosensation without hypersensitivity. Our findings advance understanding of differential collateral sprouting among sensory neuron subpopulations and may guide strategies to promote the progression of sensory recovery or limit maladaptive sensory phenomena after peripheral nerve injury. Significance Statement: Following nerve injury, whereas one mechanism for tissue reinnervation is regeneration of injured neurons, another, less well studied mechanism is collateral sprouting of nearby uninjured neurons. In this study, we examined collateral sprouting in denervated mouse skin and showed that it involves some, but not all neuronal subtypes. Despite such heterogeneity, a significant degree of restoration of punctate mechanical sensitivity is achieved. These findings highlight the diversity of collateral sprouting among peripheral neuron subtypes and reveal important differences between pre- and post-denervation skin that might be appealing targets for therapeutic correction to enhance functional recovery from denervation and prevent unwanted sensory phenomena such as pain or numbness.

2.
Int J Tuberc Lung Dis ; 22(9): 1031-1036, 2018 09 01.
Article in English | MEDLINE | ID: mdl-30092868

ABSTRACT

SETTING: Nursery for newborns in Busan, Republic of Korea. OBJECTIVE: To evaluate tuberculosis (TB) transmission from a health care worker with active pulmonary TB to neonatal contacts. DESIGN: For the first investigation, infants who had been in the nursery 3 months before the index patient was diagnosed with pulmonary TB were enrolled. After a child who had stayed in the nursery 10 months before the diagnosis of the index patient was diagnosed with tuberculous meningitis, a second contact investigation was conducted. RESULTS: Respectively 315 and 1334 children participated in the first and second investigations. The mean age of the contacts was 66.3 days; the rate of latent tuberculous infection (LTBI) at the first investigation was 42.5% (134/315). Only one infant had an abnormal chest X-ray, and was thought to have pulmonary TB. In the second investigation, the mean age of the participants was 17.6 months. The proportion of children with LTBI was 18.7% (249/1334). CONCLUSIONS: The LTBI rate in the present study was much higher than that estimated from other contact investigations. To minimise the risk of nosocomial TB transmission to neonates, screening and management of TB in health care workers should be strengthened.


Subject(s)
Cross Infection/transmission , Infectious Disease Transmission, Professional-to-Patient , Nurseries, Hospital , Nurses , Tuberculosis, Pulmonary/transmission , Adult , Contact Tracing , Female , Humans , Infant , Infant, Newborn , Latent Tuberculosis/epidemiology , Latent Tuberculosis/transmission , Male , Occupational Exposure/adverse effects , Republic of Korea/epidemiology , Risk Factors , Tuberculosis, Meningeal/epidemiology , Tuberculosis, Meningeal/transmission , Tuberculosis, Pulmonary/epidemiology
3.
Oncogene ; 36(37): 5285-5295, 2017 09 14.
Article in English | MEDLINE | ID: mdl-28504720

ABSTRACT

The Kelch-like ECH-associated protein 1 (KEAP1)-nuclear factor E2-related factor 2 (NRF2)pathway has a central role in cellular antioxidant defense. NRF2 activation due to KEAP1 or NRF2 mutations occurs frequently in many cancers, suggesting that NRF2 inhibition could be a promising therapeutic strategy. However, no potent NRF2 inhibitors are clinically available to date. To develop potent NRF2 inhibitors for therapeutic purpose, we screened ~4000 clinical compounds and determined clobetasol propionate (CP) as the most potent NRF2 inhibitor. Mechanistically, CP prevented nuclear accumulation and promoted ß-TrCP-dependent degradation of NRF2 in a glucocorticoid receptor- and a glycogen synthase kinase 3 (GSK3)-dependent manner. As a result, CP induced oxidative stress and strongly suppressed the anchorage-independent growth of tumors with KEAP1 mutation, but not with the wild-type KEAP1. Further, CP alone or in combination with rapamycin strongly inhibited the in vitro and in vivo growth of tumors harboring mutations in KEAP1 or both KEAP1 and LKB1 that are frequently observed in lung cancer. Thus, CP could be a repurposed therapeutic agent for cancers with high NRF2 activity. We also proposed that the use CP and rapamycin in combination could be a potential therapeutic strategy for tumors harboring both KEAP1 and LKB1 mutations.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Clobetasol/pharmacology , Kelch-Like ECH-Associated Protein 1/genetics , Lung Neoplasms/drug therapy , NF-E2-Related Factor 2/antagonists & inhibitors , Animals , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mice, Inbred BALB C , Mice, Nude , Random Allocation , Signal Transduction , Xenograft Model Antitumor Assays
4.
Asian-Australas J Anim Sci ; 29(1): 142-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26732338

ABSTRACT

The present study investigated the effects of back-fat thickness at d 107 of gestation and housing types during gestation on reproductive performance and behavior of sows. A total of 64 crossbred sows (Landrace×Yorkshire) in their 3 to 4 parities were allotted to one of four treatments (n = 16) over two consecutive parities. During each parity, sows were assigned to two gestational housing types (stall or group housing) and two level of back-fat thickness (<20 or ≥20) at d 107 of gestation. Gestating sows were transferred from gestational crates to stalls or pens (group housing) 5 weeks before farrowing. All sows were moved to farrowing crates on d 109 of gestation. At weaning, back-fat thickness changes were lesser (p<0.05) in sows having back-fat thickness <20 mm than that of sows with ≥20 mm back-fat thickness at 107 d of gestation. Group housed sows had greater (p<0.05) feed intake and shorter (p<0.05) weaning-to-estrus interval than that of sows in stalls. At weaning, back-fat thickness changes were lesser (p<0.05) in group housed sows than that of sows in stalls. The number of piglets at weaning, growth rate and average daily gain were greater (p<0.05) in group housed sows than that of sows in stalls. During gestation, walking duration was more (p<0.05) in group housed sows. Group housed sows had lesser (p<0.05) farrowing duration and greater (p<0.05) eating time than that of sows in stalls. Result obtained in present study indicated that sows with ≥20 mm back-fat thickness at 107 days had better reproductive performance. Additionally, group housing of sows during last five week of gestation improved the performance and behavior and reproductive efficiency of sows.

5.
J Appl Microbiol ; 119(6): 1597-612, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26426101

ABSTRACT

AIMS: Cyanobacteria have been used as sustainable bioresource producers for foods, feeds and other valuable natural products. However, selection of a new species (other than Arthrospira), with advantageous properties for alimentary purposes, continues to be a challenge due to potential toxicity and low biomass productivity. In this study, we report a valuable filamentous cyanobacterium isolated from Korea. METHODS AND RESULTS: Morphological and phylogenetic analyses demonstrated that the isolate belongs to the genus Leptolyngbya, and consequently designated Leptolyngbya sp. KIOST-1. Interestingly, Leptolyngbya sp. KIOST-1 possessed numerous advantageous characteristics for biomass production, similar to Arthrospira. The isolate readily propagated in SOT medium with efficient biomass productivity, and its optimum growth was observed at 30°C under alkaline and saline conditions. Moreover, more than half of the cellular components in Leptolyngbya sp. KIOST-1 were composed of protein, with approx. 40% of essential amino acids. Most importantly, no significant cytotoxicity was detected in the isolate. CONCLUSIONS: Leptolyngbya sp. KIOST-1 has a number of advantageous characteristics for alimentary purposes due to its efficient productivity, high protein content and lack of potential cytotoxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: Leptolyngbya sp. KIOST-1 may be considered a potential candidate for industrial biomass production, similar to Arthrospira.


Subject(s)
Biomass , Bioreactors/microbiology , Cell Culture Techniques , Cyanobacteria , Ponds/microbiology , Cyanobacteria/chemistry , Cyanobacteria/classification , Cyanobacteria/isolation & purification , Cyanobacteria/metabolism , Phylogeny , Republic of Korea
6.
Oncogene ; 31(4): 518-26, 2012 Jan 26.
Article in English | MEDLINE | ID: mdl-21743498

ABSTRACT

The serine/threonine kinase Akt is frequently activated in human cancers and is considered an attractive therapeutic target. However, the relative contributions of the different Akt isoforms to tumorigenesis, and the effect of their deficiencies on cancer development are not well understood. We had previously shown that Akt1 deficiency is sufficient to markedly reduce the incidence of tumors in Pten(+/-) mice. Particularly, Akt1 deficiency inhibits endometrial carcinoma and prostate neoplasia in Pten(+/-) mice. Here, we analyzed the effect of Akt2 deficiency on the incidence of tumors in Pten(+/-) mice. Relative to Akt1, Akt2 deficiency had little-to-no effect on the incidence of prostate neoplasia, endometrial carcinoma, intestinal polyps and adrenal lesions in Pten(+/-) mice. However, Akt2 deficiency significantly decreased the incidence of thyroid tumors in Pten(+/-), which correlates with the relatively high level of Akt2 expression in the thyroid. Thus, unlike Akt1 deletion, Akt2 deletion is not sufficient to markedly inhibit tumorigenesis in Pten(+/-) mice in most tested tissues. The relatively small effect of Akt2 deletion on the inhibition of tumorigenesis in Pten(+/-) mice could be explained, in part, by an insufficient decrease in total Akt activity, due to the relatively lower Akt2 versus Akt1 expression, and relatively high blood insulin levels in Pten(+/-)Akt2(-/-) mice. The relatively high blood insulin levels in Pten(+/-)Akt2(-/-) mice may elevate the activity of Akt1, and possibly Akt3, thus, limiting the reduction of total Akt activity and preventing this activity from dropping to a threshold level required to inhibit tumorigenesis.


Subject(s)
Neoplasms, Experimental/etiology , PTEN Phosphohydrolase/physiology , Proto-Oncogene Proteins c-akt/physiology , Adrenal Gland Neoplasms/etiology , Animals , Endometrial Neoplasms/etiology , Female , Insulin/blood , Male , Mice , Mice, Inbred C57BL , Neoplasms, Experimental/prevention & control , Prostatic Intraepithelial Neoplasia/etiology , Prostatic Neoplasms/etiology , Proto-Oncogene Proteins c-akt/deficiency , Thyroid Neoplasms/etiology
7.
Neuroscience ; 190: 354-66, 2011 Sep 08.
Article in English | MEDLINE | ID: mdl-21712071

ABSTRACT

The expression and role of monocyte chemoattractant protein-1 (MCP-1) in the rat dorsal root ganglion (DRG) and spinal cord was evaluated in the lumbar 5 ventral rhizotomy (L5 VR) model of neuropathic pain. MCP-1 protein expression in the L4/L5 DRG neurons following L5 VR peaked after 3 days, and then declined. Immunohistochemistry showed that no MCP-1 immunoreactivity was observed in the spinal cord after L5 VR, while enzyme-linked immunosorbent assay (ELISA) revealed a small but significant increase in MCP-1 protein content. L5 VR resulted in robust and prolonged mechanical allodynia and thermal hyperalgesia. Administration of anti-MCP-1 neutralizing antibody before and at early time points after L5 VR resulted in a significant attenuation of mechanical allodynia and thermal hyperalgesia, while post-treatment had a weaker effect on established neuropathic pain. Extensive colocalization of tumor necrosis factor receptor 1 (TNFR1) and MCP-1 was observed in the L5 DRG following L5 VR, and treatment with TNFR1 antisense oligonucleotide reduced L5 VR-induced MCP-1 expression in L5 DRG neurons and neuropathic pain behaviors. MCP-1/chemokine (C-C motif) receptor 2 signaling has been proposed as a major regulator of macrophage trafficking. In contrast to the effect on pain behaviors, however, intrathecal administration of anti-MCP-1 neutralizing antibody had no effect on the L5 VR-induced increase in ED-1-immunoreactive macrophages in the L5 DRG and the distal stump of the transected L5 ventral root. These data indicate that increased MCP-1 in DRG neurons might participate in the initiation, rather than the maintenance, of neuropathic pain induced by L5 VR. Furthermore, increased MCP-1 in the DRG is induced by TNF-α/TNFR1 and has no effect on the infiltration of macrophages into the DRG following L5 VR.


Subject(s)
Chemokine CCL2/metabolism , Ganglia, Spinal/metabolism , Neuralgia/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Sensory Receptor Cells/metabolism , Spinal Cord/metabolism , Animals , Disease Models, Animal , Ganglia, Spinal/physiopathology , Hyperalgesia/metabolism , Hyperalgesia/physiopathology , Male , Neuralgia/physiopathology , Physical Stimulation , Rats , Rats, Sprague-Dawley , Rhizotomy , Spinal Cord/physiopathology
8.
Eur J Cancer Care (Engl) ; 20(6): 803-9, 2011 Nov.
Article in English | MEDLINE | ID: mdl-20649810

ABSTRACT

The aim of this study was to evaluate satisfaction with the National Cancer Screening Programme of mammography in Korea and to examine the association between subscales of satisfaction and general satisfaction. We conducted a cross-sectional telephone survey for women who had obtained a National Cancer Screening Programme mammographic screening at general hospitals between May and October 2008. The present study included 2005 women in their forties. We performed multivariate linear regression using dependent variable as general satisfaction and independent variables as subscales of satisfaction, such as pre-screening information transfer, staff interpersonal skills, physical surroundings and results reporting. Participants were stratified according to the result of their mammogram as negative or positive. Mean score of satisfaction was above 2.5 of 4 for all subscales. Women who received positive results were less satisfied with all of subscale factors. Staff interpersonal skills were the most important factor that contributed to general satisfaction. Future efforts such as staff training programme of communication/attitude skills, ensuring privacy and explanation of possible discomfort of the screening would be needed.


Subject(s)
Breast Neoplasms/diagnosis , Consumer Behavior , Mammography/standards , Mass Screening/standards , Adult , Cross-Sectional Studies , Female , Humans , Korea , Middle Aged , Multivariate Analysis , Professional-Patient Relations , Surveys and Questionnaires
9.
Food Chem Toxicol ; 48(8-9): 2298-303, 2010.
Article in English | MEDLINE | ID: mdl-20573577

ABSTRACT

Anti-atherogenic effect of ferulic acid (0.02%, w/w) was investigated in comparison with the clofibrate (0.02%, w/w) in apolipoprotein E-deficient (apo E(-/-)) mice fed Western diet. Concentrations of total cholesterol (total-C), apolipoprotein B (apo B) in the plasma and epididymal adipose tissue weight were significantly lower in the ferulic acid and clofibrate supplemented groups compared to the control group. The ratio of apo B to apo A-I was also significantly lower in those groups than in the control group. Activities of hepatic ACAT and HMG-CoA reductase were only significantly lower in the ferulic acid and clofibrate groups, respectively than in the control group. The numbers of mice that exhibited aortic fatty plaque were 8/10 in control groups vs. 0/10 in the ferulic acid or clofibrate group. The activities of anti-oxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and paraoxonase) in the hepatocyte and erythrocyte were significantly higher in the ferulic acid group than in the control group. In contrast, hepatic TBARS level was only markedly lower in the ferulic acid group. These results provide a new insight into the anti-atherogenic property of ferulic acid in the apo E(-/-) mice fed a Western diet.


Subject(s)
Anticholesteremic Agents/pharmacology , Apolipoproteins E/genetics , Atherosclerosis/prevention & control , Clofibrate/pharmacology , Coumaric Acids/pharmacology , Diet , Adipose Tissue/drug effects , Animals , Antioxidants/pharmacology , Apolipoproteins E/physiology , Aryldialkylphosphatase/metabolism , Atherosclerosis/pathology , Eating/drug effects , Hydroxymethylglutaryl CoA Reductases/metabolism , Lipid Peroxidation/drug effects , Lipids/blood , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Organ Size/drug effects , Sterol O-Acyltransferase/metabolism , Weight Gain/drug effects
10.
Clin Microbiol Infect ; 14(8): 760-5, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18727800

ABSTRACT

Among 5938 clinical Shigella spp. isolates, two S. flexneri strains were isolated as those resistant to fluoroquinolones based on the MICs of the following antibiotics: ciprofloxacin, norfloxacin, ofloxacin, sparfloxacin and levofloxacin. S. flexneri 021787 had three substitutions, one in GyrA (Ser83Leu) and two in ParC (Ser80Ile and Arg91Gln). S. flexneri 021895 had four substitutions, two in GyrA (Ser83Leu and Asp87Gly) and two in ParC (Ser80Ile and Arg91Gln). The increased susceptibility of S. flexneri 021787 and S. flexneri 021895 to ciprofloxacin, norfloxacin and ofloxacin in the presence of the uncoupler carbonyl cyamide-m-chlorophenyldrazone implied that energy-dependent active efflux pumps contributed to the resistance against fluoroquinolones. Both S. flexneri 021787 and S. flexneri 021895 were also induced to express tolC (encoding a resistance-nodulation-division transporter), mdfA (encoding a major facilitator superfamily transporter), and ydhE (encoding a multidrug and toxic compound extrusion transporter) in the presence of ciprofloxacin. Thus, these results indicated that chromosome-mediated fluoroquinolone resistance of S. flexneri 021787 and S. flexneri 021895 resulted from the combination of target site mutations and enhanced expression of genes encoding efflux pumps.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Drug Resistance, Bacterial/genetics , Fluoroquinolones/pharmacology , Mutation , Shigella flexneri/drug effects , Shigella sonnei/drug effects , Bacterial Proteins/genetics , DNA Gyrase/genetics , DNA Gyrase/metabolism , DNA Topoisomerase IV/genetics , DNA Topoisomerase IV/metabolism , Dysentery, Bacillary/microbiology , Gene Expression Regulation, Bacterial , Humans , Korea , Microbial Sensitivity Tests , Shigella flexneri/genetics , Shigella sonnei/genetics
11.
Neuroscience ; 146(3): 1128-36, 2007 May 25.
Article in English | MEDLINE | ID: mdl-17395388

ABSTRACT

The present study was undertaken to characterize the regional and temporal patterns of brain-derived neurotrophic factor (BDNF) in the rat forebrain and upper brain stem during postnatal development using an immunohistochemical approach. Results indicated that BDNF-immunoreactive (IR) cells could be divided into three groups based on their postnatal developmental patterns: (group 1) BDNF-IR cells were first detected between postnatal days (PND) 1 and 7, and thereafter they increased in number and remained stable during later stages of ontogeny; (group 2) BDNF-IR cells progressively increased in number with age, and then decreased in adults; (group 3) numerous BDNF-IR cells detected between PND 1 and 7 showed a dramatic reductions in number with few IR cells in adults. In contrast, the developmental pattern of most BDNF-IR fibers differed from that of IR neurons, i.e. they appeared between PND 1-28 and thereafter continued to increase in number showing a maximum level in adults. Additionally, BDNF-IR cells in the superficial layer of the neocortex and IR fibers in the stratum oriens of CA2 first appeared as late as PND 28 and in adults, respectively. After colchicine treatment, reexpression or a marked increase in the number of BDNF-IR neurons was observed in many areas of the adult brain where a progressive decrease in BDNF-IR cell numbers during development and scant or some IR neurons in adults were shown. These results showed both transient and persistent expression of BDNF in various regions of the developing rat brain.


Subject(s)
Animals, Newborn/physiology , Brain Stem/metabolism , Brain-Derived Neurotrophic Factor/biosynthesis , Prosencephalon/metabolism , Animals , Brain Stem/cytology , Brain Stem/growth & development , Cell Count , Colchicine/pharmacology , Diencephalon/growth & development , Diencephalon/metabolism , Immunohistochemistry , Male , Mesencephalon/growth & development , Mesencephalon/metabolism , Nerve Fibers/metabolism , Neurons/drug effects , Neurons/metabolism , Prosencephalon/cytology , Prosencephalon/growth & development , Rats , Rats, Sprague-Dawley , Telencephalon/growth & development , Telencephalon/metabolism
12.
Clin Chim Acta ; 314(1-2): 221-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11718699

ABSTRACT

BACKGROUND: Polyphenols appear to have antioxidant activities and may mediate lipid lowering. METHODS: Four groups of rats, a high-cholesterol control (HC), HC+lovastatin, HC+3,4-di(OH)-cinnamate, and HC+3,4-di(OH)-hydrocinnamate, were given a semi-synthetic diet. The cinnamate derivative or lovastatin (0.1 g/100 g) supplements were given for 6 weeks. RESULTS: The plasma total cholesterol concentration was significantly lowered by the 3,4-di(OH)-cinnamate supplement compared to the control or lovastatin group. The 3,4-di(OH)-cinnamate and 3,4-di(OH)-hydrocinnamate supplements significantly lowered both the hepatic cholesterol and triglyceride levels, while lovastatin only lowered the hepatic cholesterol. The hepatic HMG-CoA reductase activities were significantly lower in the 3,4-di(OH)-cinnamate and 3,4-di(OH)-hydrocinnamate groups than in the control or lovastatin group. The ACAT activity was only significantly lower in the lovastatin group compared to the other groups. With regards the hepatic antioxidant enzyme system, the CAT activity was significantly higher in the 3,4-di(OH)-cinnamate and 3,4-di(OH)-hydrocinnamate groups compared to the control or lovastatin group. The two cinnamate derivatives resulted in an increased hepatic GSH-Px activity. Meanwhile, all the supplements significantly lowered the hepatic thiobarbituric acid reactive substances (TBARS) content. However, the 3,4-di(OH)-cinnamate and 3,4-di(OH)-hydrocinnamate supplements did not alter the neutral sterol and total fecal sterol. CONCLUSIONS: Both cinnamate derivatives were potent in lipid-lowering and altering the antioxidative enzyme. Furthermore, these results also suggest that 3,4-di(OH)-cinnamate is more effective than 3,4-di(OH)-hydrocinnamate in its lipid-lowering action.


Subject(s)
Antioxidants/pharmacology , Cholesterol, Dietary/pharmacology , Cinnamates/pharmacology , Hypolipidemic Agents/pharmacology , Animals , Cholesterol, Dietary/metabolism , Diet , Eating , Feces/chemistry , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Lipid Metabolism , Lipids/blood , Liver/drug effects , Liver/enzymology , Liver/metabolism , Male , Organ Size/drug effects , Phosphatidylcholine-Sterol O-Acyltransferase/metabolism , Rats , Rats, Sprague-Dawley , Sterols/chemistry , Thiobarbituric Acid Reactive Substances/metabolism , Weight Gain/drug effects
13.
Life Sci ; 69(24): 2855-66, 2001 Nov 02.
Article in English | MEDLINE | ID: mdl-11720089

ABSTRACT

The consumption of a cholesterol-enriched diet increases the degree of lipid peroxidation, which is one of the early processes of atherosclerosis. The aim of this trial was to determine the antioxidative effects of the citrus bioflavonoid, naringin, a potent cholesterol-lowering agent, compared to the cholesterol-lowering drug, lovastatin, in rabbits fed a high cholesterol diet. Male rabbits were served a high-cholesterol (0.5%, w/w) diet or high-cholesterol diet supplemented with either naringin (0.5% cholesterol, 0.05% naringin, w/w) or lovastatin (0.5% cholesterol, 0.03% lovastatin, w/w) for 8 weeks to determine the plasma and hepatic lipid peroxide, plasma vitamin A and E levels, and hepatic hydrogen peroxide levels, along with the hepatic antioxidant enzyme activities and gene expressions. Only the lovastatin group showed significantly lower plasma and hepatic lipid peroxide levels compared to the control group. The naringin supplementation significantly increased the activities of both hepatic SOD and catalase by 33% and 20%, respectively, whereas the lovastatin supplementation only increased the catalase activity by 23% compared to control group. There was no difference in the GSH-Px activities between the various groups. Content of H2O2 in hepatic mitochondria was significantly lower in groups supplemented with lovastatin and naringin than in control group. However, there was no difference in cytosolic H2O2 content in liver between groups. The concentration of plasma vitamin E was significantly increased by the naringin supplementation. When comparing the antioxidant enzyme gene expression, the mRNA expression of SOD, catalase and GSH-Px was significantly up-regulated in the naringin-supplemented group. Accordingly, these results would appear to indicate that naringin, a citrus bioflavonoid, plays an important role in regulating antioxidative capacities by increasing the SOD and catalase activities, up-regulating the gene expressions of SOD, catalase, and GSH-Px, and protecting the plasma vitamin E. In contrast, lovastatin exhibited an inhibitory effect on the plasma and hepatic lipid peroxidation and increased the hepatic catalase activity in high-cholesterol fed rabbits.


Subject(s)
Anticholesteremic Agents/pharmacology , Antioxidants/pharmacology , Cholesterol, Dietary/administration & dosage , Diet, Atherogenic , Flavanones , Flavonoids/pharmacology , Lovastatin/pharmacology , Animals , Body Weight/drug effects , Catalase/genetics , Catalase/metabolism , Cytosol/chemistry , Cytosol/drug effects , Cytosol/enzymology , Gene Expression Regulation, Enzymologic/drug effects , Glutathione Peroxidase/genetics , Glutathione Peroxidase/metabolism , Hydrogen Peroxide/analysis , Lipid Peroxidation/drug effects , Lipid Peroxides/analysis , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Mitochondria, Liver/chemistry , Mitochondria, Liver/drug effects , Mitochondria, Liver/enzymology , Organ Size/drug effects , RNA, Messenger/metabolism , Rabbits , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Vitamin A/blood , Vitamin E/blood
14.
Ann Nutr Metab ; 45(5): 193-201, 2001.
Article in English | MEDLINE | ID: mdl-11585976

ABSTRACT

Some bioflavonoids are potent antioxidants and have pharmacological effects similar to those of vitamin E. The interactive effect of naringin and vitamin E was studied with respect to cholesterol metabolism and antioxidant status. Naringin supplementation (0.1%, wt/wt) with comparable levels of vitamin E was given to rats with a high-cholesterol (1%, wt/wt) diet for 5 weeks. The amount of vitamin E included in naringin-free and naringin diets was a low (low-E) and a normal (normal-E) level. The naringin supplementation significantly lowered the concentrations of plasma cholesterol and triglyceride compared to the naringin-free group in low vitamin E-fed rats. HMG-CoA reductase activity was significantly lowered by naringin supplementation within both the low-vitamin E group (794.64 +/- 9.87 vs. 432.18 +/- 12.33 pmol/min/mg protein, mean +/- SE; p < 0.05) and normal-vitamin E group (358.82 +/- 11.4 vs. 218.22 +/- 9.47 pmol/min/mg protein, mean +/- SE; p < 0.05) compared to each of the naringin-free group. The HMG-CoA reductase activity was also significantly lowered by increased dietary vitamin E when compared within the naringin and naringin-free group, respectively. Neither dietary naringin nor vitamin E did significantly change the activities of hepatic antioxidant enzymes and plasma thiobarbituric acid-reactive substance level. These data indicate that naringin lowers the plasma lipid concentrations when the dietary vitamin E level is low. The HMG-CoA reductase-inhibitory effect of naringin was more potent when dietary vitamin E was at a normal level. These data may contribute to understanding the interactive effect of naringin and vitamin E on cholesterol biosynthesis in high-cholesterol-fed rats.


Subject(s)
Antioxidants/administration & dosage , Cholesterol, Dietary/administration & dosage , Cholesterol/metabolism , Flavanones , Flavonoids/administration & dosage , Vitamin E/administration & dosage , Animals , Cholesterol/biosynthesis , Dietary Supplements , Drug Interactions , Hydroxymethylglutaryl CoA Reductases/metabolism , Liver/enzymology , Male , Rats , Rats, Sprague-Dawley
15.
Am J Chin Med ; 29(2): 343-54, 2001.
Article in English | MEDLINE | ID: mdl-11527076

ABSTRACT

This study was performed to investigate the effect of Puerariae Flos (PF) and Puerariae Radix (PR) water extracts on the activities and mRNA expression of three hepatic antioxidant enzymes in ethanol-treated rats. Male Sprague-Dawley rats were divided into four groups, a control, ethanol-treated, ethanol plus PF-treated, and ethanol plus PR-treated group with seven rats per group. Ethanol (25 % v/v, 5 g/kg body weight) was orally administered once a day for 5 weeks. The PF and PR water extracts were supplemented in a diet based on 1.2 g of raw PF or PR/kg body weight/day. Ethanol administration without the PF or PR supplement significantly lowered the activities of hepatic Cu/Zn SOD and catalase (CAT), whereas it increased the hepatic GSH-Px activity. However, the PF and PR supplementation resulted in a significant increase in the Cu/Zn SOD and/or CAT activities and a significant decrease in the GSH-Px activity in the ethanol-treated rats. The mRNA levels of these antioxidant enzymes in the ethanol-treated rats were normalized to the control level by the PF or PR supplement. The hepatic glutathione content, which was significantly lower in the ethanol-treated group than in the control group, was also normalized to the control level by supplementing with either PF or PR. The PF or PR supplement resulted in lowering the hepatic malondialdehyde to the control level in the ethanol-treated rats.


Subject(s)
Antioxidants/metabolism , Central Nervous System Depressants/metabolism , Drugs, Chinese Herbal/pharmacology , Ethanol/metabolism , Liver/metabolism , Oxidative Stress/drug effects , Animals , Blotting, Northern , Catalase/metabolism , Copper/metabolism , DNA Probes , Glutathione Peroxidase/metabolism , In Vitro Techniques , Liver/enzymology , Male , Medicine, Chinese Traditional , Pueraria , RNA, Messenger/drug effects , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Superoxide Dismutase/metabolism , Zinc/metabolism
16.
Ann Nutr Metab ; 45(4): 152-8, 2001.
Article in English | MEDLINE | ID: mdl-11463998

ABSTRACT

Currently, there is a growing need for food irradiation that is effective in food preservation and quality improvement. Accordingly, this study was designed to observe the effects of gamma-irradiated dietary fat on plasma lipid concentrations and hepatic cholesterol metabolism in rats. Male rats were fed 5-kGy-gamma-irradiated beef tallow (gammaBT), corn oil (gammaCO), perilla oil (gammaPO), and nonirradiated fats (BT, CO, and PO) for 6 weeks. The gamma-irradiated fat feeding did not affect the plasma lipid concentrations. However, the hepatic cholesterol content was significantly higher in the rats fed gamma-CO as compared with the rats fed nonirradiated CO (40.0 vs. 28.2 mg/g liver). The hepatic HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase activities were not significantly different between the controls and the gamma-irradiated fat fed groups. However, the hepatic ACAT (acyl-CoA:cholesterol acyltransferase) activity was significantly lower in the gammaPO group as compared with its control group (138.2 vs. 404.5 pmol min(-1) mg(-1)). Among the nonirradiated groups, the ACAT activities of the CO and PO groups were higher than that of the BT group. The amounts of coprostanone, cholesterol, and total fecal neutral sterol were significantly higher in the gammaPO group as compared with the other groups. These results indicate that although slight changes in the lipid metabolism were observed as a result of 5-kGy-gamma-irradiated fat feeding, they were relative to the fat type and had no harmful consequences.


Subject(s)
Cholesterol/metabolism , Dietary Fats/radiation effects , Lipids/blood , Liver/metabolism , Animals , Cholestanes/analysis , Cholesterol/analysis , Corn Oil/administration & dosage , Corn Oil/radiation effects , Dietary Fats/administration & dosage , Fats/administration & dosage , Fats/radiation effects , Feces/chemistry , Food Irradiation , Gamma Rays , Hydroxymethylglutaryl CoA Reductases/metabolism , Lipid Metabolism , Liver/enzymology , Male , Organ Size , Plant Oils , Random Allocation , Rats , Rats, Sprague-Dawley , Sterol O-Acyltransferase/metabolism , Thiobarbituric Acid Reactive Substances/analysis , Weight Gain , alpha-Linolenic Acid/administration & dosage , alpha-Linolenic Acid/radiation effects
17.
Ann Nutr Metab ; 45(6): 279-84, 2001.
Article in English | MEDLINE | ID: mdl-11786651

ABSTRACT

Areca extracts have already been found to exhibit a strong inhibitory activity on cholesterol absorption in high-cholesterol-fed rats. Accordingly, this study was performed to determine whether Areca extracts also exert an inhibitory activity on triglyceride absorption in triglyceride-fed rats. Male rats were fed a diet containing corn oil (10%, w/w) with or without an Areca nut extract supplement (0.5%, w/w). The supplementation of the Areca extract significantly lowered the absorption of triglyceride and the plasma lipid concentration. The absorbed triglyceride that appeared in the blood after an oral dose of [9,10(n)-(3)H] triglyceride was significantly lower in the rats supplemented with the Areca nut extract, compared with the control group. The supplementation also significantly lowered the small intestinal pCEase (pancreatic cholesterol esterase) activity by 22.5% compared to the control group. The hepatic and intestinal ACAT (acyl-CoA:cholesterol acyltransferase) activities were significantly decreased in the Areca group compared with the control group. Hence, further studies are needed to elucidate the structure and chemical properties of the active compound in the water-soluble Areca extract that lowers cholesterol absorption.


Subject(s)
Areca/chemistry , Cholesterol, Dietary/pharmacokinetics , Intestinal Absorption/drug effects , Plant Extracts/pharmacology , Triglycerides/pharmacokinetics , Animals , Biological Availability , Cholesterol/blood , Dietary Supplements , Hypolipidemic Agents/pharmacology , Intestine, Small/enzymology , Liver/enzymology , Male , Nuts/chemistry , Pancreas/enzymology , Rats , Rats, Sprague-Dawley , Sterol Esterase/antagonists & inhibitors , Sterol Esterase/metabolism , Sterol O-Acyltransferase/antagonists & inhibitors , Sterol O-Acyltransferase/metabolism
18.
Ann Nutr Metab ; 44(4): 170-6, 2000.
Article in English | MEDLINE | ID: mdl-11111132

ABSTRACT

Areca catechu L. extracts I and II, prepared using two different solvent systems, exhibited strong inhibitory activities against pancreatic cholesterol esterase (pCEase) in vitro. To determine their cholesterol-lowering effects, these two extracts were investigated by analyzing plasma lipid levels, intestinal enzyme activities, and the absorption of cholesteryl oleate. For 6 days, male rats were fed a diet containing cholesteryl oleate (0.5 g/100 g of body weight) either with or without the Areca nut extract supplements. The supplementation of the two Areca nut extracts significantly lowered the concentrations of plasma cholesterol by 13. 4 and 11.7% and plasma triglycerides by 35.0 and 36.9%, respectively, compared with the pre-experimental values. However, when the cholesteryl oleate diet was fed without any Areca nut extract in high-cholesterol control, the plasma cholesterol and triglyceride concentrations significantly increased by 13.6 and 15.9%, respectively, compared with the pre-experimental values. After 6 days of treatment, the intestinal pCEase activities were significantly lower in the groups supplemented with the Areca nut extracts (37.8 and 26.5%) than in the group with no extract supplement (83.2%). The supplements also significantly elevated the excretion of [1,2(n)-(3)H]cholesteryl oleate administered orally, when determined by the large intestinal contents, 930.5 Bq/day (Areca I) and 1,766.3 Bq/day (Areca II) vs. 98.1 Bq/day (high-cholesteryl oleate (CO) control). The inhibition of pCEase activity with the supplementation of the Areca nut extracts could account for the decrease in [1,2(n)-(3)H]cholesteryl oleate absorption that resulted in decreased radioactivity in blood.


Subject(s)
Areca/chemistry , Cholesterol Esters/administration & dosage , Cholesterol/blood , Intestinal Absorption/drug effects , Pancreas/enzymology , Plants, Medicinal , Triglycerides/blood , Animals , Cholesterol Esters/pharmacokinetics , Cholesterol Esters/pharmacology , Gastrointestinal Contents/chemistry , Gastrointestinal Contents/enzymology , Hypolipidemic Agents , Male , Plant Extracts/pharmacology , Rats , Rats, Sprague-Dawley , Sterol Esterase/antagonists & inhibitors
19.
Korean J Parasitol ; 34(3): 197-206, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8843696

ABSTRACT

Water extract of Coix lacryma seeds (Co-Ex) was separated into several components; dissolved with Tris-Cl buffer and the supernatant (WC1), ammonium sulfate treatment supernatant (WC2) and the pellet (WC3), QAE column chromatography of WC1 and the peak portions; WC4, WC5 and WC6. Murine peritoneal macrophages in DMEM containing 10% heat-inactivated FCS were infected with tachyzoites of Toxoplasma gondii, RH strain, in vitro. By adding modulators such as Co-Ex, WC1,2,3,4,5,6 and LPS or IFN-gamma for 24 hrs, toxoplasmastatic activity of macrophages was examined in relation to nitrite production. Nitrite production of macrophages was enhanced especially in the series of WC2, WC1 and the combination sample (WC1+WC2+WC3) by order, than other components or fractions (WC4, WC5, WC6) tested. Toxoplasmastatic actions such as percentage of the macrophages infected by T. gondii and fold increase of T. gondii in macrophages showed retroverse relations with the amount of nitrite production; i.e., as nitric oxide (NO) increased the phagocytic index of macrophages and the fold increase of tachyzoites in macrophages decreased. Nitrite (NO2) production was increased by adding IFN-gamma in all cases together with enhancement of biostatic effects. Through the results obtained, it is speculated that some components other than the non-proteinous and defatted components in Coix lacryma seeds may contribute to activate macrophages through induction of NO for the biostatic activity.


Subject(s)
Macrophages, Peritoneal/parasitology , Plant Extracts/pharmacology , Plants, Medicinal , Toxoplasma/drug effects , Animals , Cells, Cultured , Macrophages, Peritoneal/metabolism , Mice , Nitric Oxide/metabolism
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