The objective of this study was to determine the concentration of serum l-arginine in healthy pregnant women and infant cord blood and to compare them with those in patients with pregnancy-induced hypertension (PIH). The serum concentration of l-arginine in normal pregnant women at early gestation (n = 186) was determined and analyzed based on maternal factors such as the age, pre-pregnancy body mass index (BMI), smoking and alcohol habits before pregnancy. Similarly, the concentration of cord blood of the newborns (n = 142) was also analyzed. These values were compared with those in the PIH group (n = 21). The potential risk factors for PIH were also estimated. The serum concentration of l-arginine at early gestation in normal pregnant women (88.65 ± 19.96 µM) was not affected by the maternal age and BMI before pregnancy. A lower l-arginine concentration at early gestation (<70 µM) significantly elevated PIH risk [adjusted odds ratio (OR) = 4.26, 95% CI 1.29–14.50]. In addition, either women with large body mass before pregnancy (BMI>25 kg/m2) or primipara women also showed a significant association with PIH risk [adjusted OR = 10.55 (2.95–40.68); 5.25 (1.72–19.15), respectively]. In conclusion, a lower l-arginine concentration at early gestation, overweight before pregnancy (BMI>25 kg/m2) and primipara could predict to the development of PIH.
l-arginine; pregnancy-induced hypertension; parity; cord blood
Reactive oxygen species not only cause damage but also have a physiological role in the protection against pathogens and in cell signalling. Mitochondrial nutrients, such as coenzyme Q10 and α-lipoic acid, beside their acknowledged antioxidant activities, show interesting features in relation to their redox state and consequent biological activity. In this study, we tested whether oral supplementation with 200 mg/day of coenzyme Q10 alone or in association with 200 mg/die of α-lipoic acid for 15 days on 16 healthy subjects was able to modulate the oxidative status into different compartments (plasma and cells), in basal condition and following an oxidative insult in peripheral blood lymphocytes exposed in vitro to H2O2. Data have shown that tested compounds produced antioxidant and bioenergetic effects improving oxidative status of the lipid compartment and mitochondrial functionality in peripheral blood lymphocytes. Simultaneously, an increased intracellular reactive oxygen species level was observed, although they did not lead to enhanced DNA oxidative damage. Coenzyme Q10 and α-lipoic acid produced beneficial effects also steering intracellular redox poise toward a pro-oxidant environment. In contrast with other antioxidant molecules, pro-oxidant activities of tested mitochondrial nutrients and consequent oxidant mediated signalling, could have important implications in promoting adaptive response to oxidative stress.
Coenzyme Q10 ; α-lipoic acid; reactive oxygen species; mitochondrial functionality; DNA damage
The purpose of the present study was to investigate hypolipidemic and anti-inflammatory effects of Artemisia vulgaris extract in hypercholesterolemic rats. Hypercholesterolemia was induced by feeding of rats with high fat diet containing 3% cholesterol in olein oil, for 8 weeks. Feeding of rats with high fat diet for 8 weeks, leading to a significant increase in serum triglycerides, total cholesterol, low density lipoprotein cholesterol, malondialdehyde and nitric oxide, tumor necrosis factor-α levels and a significant decrease in serum high density lipoprotein cholesterol level, liver hydroxymethylglutaryl-CoA reductase activity and paraoxonase-1 activities as compared to the normal control group. Treatment of high fat diet rats with Artemisia vulgaris extract for 4 weeks at a dose of 100 mg/kg per day, resulted in normalized serum lipid profile, a significant increase in paraoxonase-1 activity and decrease in serum malondialdehyde, nitric oxide and tumor necrosis factor-α level as compared to high fat diet-treated animals. Also the extract caused a significant decrease in hydroxymethylglutaryl-CoA reductase activity as compared with both high fat diet-treated animals and control ones. In conclusion, Artemisia vulgaris extract has hypolipidemic, anti-inflammatory, antioxidant properties; it may serve as a source for the prevention of atherosclerosis and cardiovascular diseases.
hypercholesterolemia; atherosclerosis; Artemisia vulgaris extract; TC; TG
It has been demonstrated that cancer cells are under high levels of oxidative stress and express high levels of Manganese superoxide dismutase (MnSOD) to protect themselves and support the anabolic metabolism needed for growth and cell motility. The aim of this study was to identify proteins that may have a correlation with invasion and redox regulation by mitochondrial reactive oxygen species (ROS). MnSOD scavenges superoxide anions generated from mitochondria and is an important regulator of cellular redox status. Oxidative posttranslational modification of cysteine residues is a key mechanism that regulates protein structure and function. We hypothesized that MnSOD regulates intracellular reduced thiol status and promotes cancer invasion. A proteomic thiol-labeling approach with 5-iodoacetamidofluorescein was used to identify changes in intracellular reduced thiol-containing proteins. Our results demonstrate that overexpression of MnSOD maintained the major structural protein, actin, in a reduced state, and enhanced the invasion ability in gastric mucosal cancer cells, RGK1. We also found that the expression of Talin and S100A4 were increased in MnSOD-overexpressed RGK1 cells. Moreover, Talin bound not only with actin but also with S100A4, suggesting that the interaction of these proteins may, in part, contribute to the invasive ability of rat gastric cancer.
reduced form of actin; actin binding protein; cancer invasion; MnSOD; ROS
The study examined the global metabolic and some biochemical changes in rats with cholestasis induced by bile duct ligation (BDL). Serum samples were collected in male Wistar rats with BDL (n = 8) and sham surgery (n = 8) at day 3 after surgery for metabolomics analysis using a combination of reversed phase chromatography and hydrophilic interaction chromatography (HILIC) and quadrupole-time-of-flight mass spectrometry (Q-TOF MS). The serum levels of malondialdehyde (MDA), total antioxidative capacity (T-AOC), glutathione (GSH) and glutathione disulfide (GSSG), the activities of superoxide dismutase (SOD) and glutathion peroxidase (GSH-Px) were measured to estimate the oxidative stress state. Key changes after BDL included increased levels of l-phenylalanine, l-glutamate, l-tyrosine, kynurenine, l-lactic acid, LysoPCc (14:0), glycine and succinic acid and decreased levels of l-valine, PCb (19:0/0:0), taurine, palmitic acid, l-isoleucine and citric acid metabolism products. And treatment with BDL significantly decreased the levels of GSH, T-AOC as well as SOD, GSH-Px activities, and upregulated MDA levels. The changes could be mapped to metabolism of amino acids and lipids, Krebs cycle and glycolysis, as well as increased oxidative stress and decreased antioxidant capability. Our study indicated that BDL induces major changes in the metabolism of all 3 major energy substances, as well as oxidative stress.
obstructive jaundice; metabolomics; RPLC-MS; HILIC-MS; oxidative stress
Functional foods that provide benefits beyond their traditional nutritional value have attracted much interest. Aim of the study was to evaluate the nutritional and the functional properties of a frozen ready-to-eat soup containing barley and pigmented vegetables. Both glycaemic index and the glyceamic load of ready-to-eat soup were evaluated in vivo. Moreover the bioavailability of carotenoids (lutein and beta-carotene) and the effect on lipid profile and lipid peroxidation were studied in 38 volunteers whose diet was supplemented for two weeks with a daily portion (250 g) of the ready-to-eat soup. Plasma levels of carotenoids (lutein and beta-carotene) and plasma total antioxidant capacity significantly increased after 2 weeks of treatment. Furthermore, we observed a decrease in the levels of lipids (total cholesterol and low density lipoprotein-cholesterol) and of markers of lipid peroxidation (oxidized low density lipoprotein and lipid hydroperoxides) in plasma of all subjects. The glyceamic index of the product was 36, therefore it could be considered a low glyceamic index food. An accurate selection of vegetable foods results in a palatable and healthy product that provides benefits on plasma lipids and lipid peroxidation (Protocol number 211525).
oxidized-LDL; carotenoids; oxidative stress; functional food; glyceamic index
The inhibition of advanced glycation end-products (AGEs) by daily meals is believed to become an effective prevention for lifestyle-related diseases. In the present study, the inhibitory effect of hot water extracts of mangosteen (Garcinia mangostana L.) pericarp (WEM) on the formation of pentosidine, one of AGEs, in vitro and in vivo and the remedial effect on skin conditions were measured. WEM significantly inhibited pentosidine formation during gelatin incubation with ribose. Several compounds purified from WEM, such as garcimangosone D and rhodanthenone B, were identified as inhibitors of pentosidine formation. Oral administration of WEM at 100 mg/day to volunteer subjects for 3 months reduced the serum pentosidine contents. Because obtaining skin biopsies from healthy volunteers is ethically difficult, AGE accumulation in the skin was estimated by a fluorescence detector. The oral administration of WEM significantly reduced the skin autofluorescence intensity, demonstrating that WEM also reduced AGE accumulation in the skin. Furthermore, the elasticity and moisture content of the skin was also improved by WEM. These results demonstrate that intakes of WEM reduces the glycation stress and results in the improvement of skin conditions.
AGEs; pentosidine; mangosteen; oxidation; skin elasticity
Secretory immunoglobulin A (sIgA) is produced from intestinal mucosa and is essential in preventing infection. We analyzed the influence of moderate exercise on intestinal sIgA production and antioxidative function under different carbohydrate nutritional conditions. Thirty-six mice were fed an experimental diet for 10 weeks—a high-carbohydrate (HC) diet, a low-carbohydrate (LC) diet, or a control (C) diet. After 1 week on the experimental diets, mice were divided into sedentary and exercise groups (n = 6/group), where the exercise consisted of treadmill running for 30 min/day at 11 m/min for 6 days/week in 9 consecutive weeks. Intestinal sIgA levels in the exercise groups fed C or LC diets were significantly lower compared with the parallel sedentary groups, or exercise-group mice fed HC diet. Expression of the polymeric immunoglobulin receptor (pIgR) in the small intestine was significantly higher in the exercise group fed a HC diet. Superoxide dismutase activity in the small intestine was higher in the exercise group than in the sedentary group, with no effects resulting from intake carbohydrate levels. Our results indicated that moderate exercise reduced the levels of intestinal sIgA depending on decreasing of carbohydrate intake, which is connected with the expression of pIgR.
sIgA; moderate exercise; carbohydrate intake; pIgR; SOD
Limonoids in citrus fruits are known to possess multiple biological functions, such as anti-proliferative functions in human cancer cell lines. Therefore, we aimed to investigate the suppressive effect of limonin on intestinal polyp development in Apc-mutant Min mice. Five-week-old female Min mice were fed a basal diet or a diet containing 250 or 500 ppm limonin for 8 weeks. The total number of polyps in mice treated with 500 ppm limonin decreased to 74% of the untreated control value. Neoplastic cell proliferation in the polyp parts was assessed by counting PCNA positive cells, and a tendency of reduction was obtained by limonin treatment. Moreover, expression levels of c-Myc and MCP-1 mRNA in the polyp part were reduced by administration of limonin. We finally confirmed the effects of limonin on β-catenin signaling, and found limonin significantly inhibited T-cell factor/lymphocyte enhancer factor-dependent transcriptional activity in a dose-dependent manner in the Caco-2 human colon cancer cell line. Our results suggest that limonin might be a candidate chemopreventive agent against intestinal carcinogenesis.
limonin; Min mice; colon cancer; c-Myc; Tcf/Lef
Advanced glycation end-products are toxic by-products of metabolism and are also acquired from high-temperature processed foods. They promote oxidative damage to proteins, lipids and nucleotides. Aging and chronic diseases are strongly associated with markers for oxidative stress, especially advanced glycation end-products, and resistance to peripheral insulin-mediated glucose uptake. Modifiable environmental factors including high levels of refined and simple carbohydrate diets, hypercaloric diets and sedentary lifestyles drive endogenous formation of advanced glycation end-products via accumulation of highly reactive glycolysis intermediates and activation of the polyol/aldose reductase pathway producing high intracellular fructose. High advanced glycation end-products overwhelm innate defenses of enzymes and receptor-mediated endocytosis and promote cell damage via the pro-inflammatory and pro-oxidant receptor for advanced glycation end-products. Oxidative stress disturbs cell signal transduction, especially insulin-mediated metabolic responses. Here we review emerging evidence that restriction of dietary advanced glycation end-products significantly reduces total systemic load and insulin resistance in animals and humans in diabetes, polycystic ovary syndrome, healthy populations and dementia. Of clinical importance, this insulin sensitizing effect is independent of physical activity, caloric intake and adiposity level.
oxidative stress; insulin resistance; glycation; AGEs; Western diet
The present study was conducted to assess the relationship between metabolic syndrome and metabolic syndrome score (MSS) and serum vitamin D levels in adults aged 20 or older (n = 5,483) using 2012 Korean National Health and Nutrition Examination Survey data, which represents national data in Korea. Key study results were as follows: First, serum 25-hydroxyvitamin D [25(OH)D] levels decreased significantly with an increase in MSS (p = 0.004), shown by serum 25(OH)D levels after adjusting the variables (age, gender, BMI, TC, HDL-C, FBS, SBP, and DBP, etc.). These were 17.30 ± 0.16 ng/ml for MSS 0, 17.13 ± 0.15 ng/ml for MSS 1, 17.02 ± 0.16 ng/ml for MSS 2, 16.60 ± 0.20 ng/ml for MSS 3, 16.55 ± 0.28 ng/ml for MSS 4, and 15.52 ± 0.50 ng/ml for MSS 5. Second, after adjusting the related variables, serum 25(OH)D levels were significantly lower (p = 0.004) in the metabolic syndrome group (16.49 ± 0.19 ng/ml) than the non-metabolic syndrome group (17.16 ± 0.09 ng/ml). In conclusion, metabolic syndrome and the increased levels of its components are inversely associated with the serum vitamin D concentration in Korean adults.
25-hydroxyvitamin D; metabolic syndrome; metabolic syndrome score
This study assessed time-course changes of the small intestinal lesions during long-term treatment with diclofenac sodium plus omeprazole and the effects of irsogladine on such lesions. Thirty two healthy volunteers were treated with diclofenac sodium (75 mg/day) plus omeprazole (10 mg/day) for 6 weeks, with irsogladine (4 mg/day) added from weeks 6 to 10 (Group A) or with diclofenac sodium plus irsogladine for 6 weeks (Group B). Five volunteers received diclofenac sodium plus omeprazole for 10 weeks (Group C). Subjects underwent capsule endoscopy at each time. In Group A, the number of lesions remarkably increased at week 2, but the worse was not found at week 6 compared with week 2, whereas no exacerbation of lesions was observed in Group B. Additional treatment with irsogladine from weeks 6 to 10 in Group A significantly decreased the number of lesions at weeks 10 compared with Group C. In Group C, no significant change in lesions was observed since weeks 2. In conclusions, a PPI did not prevent the occurrence of small intestinal damage. However such lesions were not aggravated since weeks 2. These suggested mucosal adaptation may occur in the small intestine. Irsogladine was effective in both preventing and healing such lesions.
NSAIDs; PPI; irsogladine; small bowel; capsule endoscopy
Pruni cortex, the bark of Prunus jamasakura Siebold ex Koidzumi, has been used in the Japanese systems of medicine for many years for its anti-inflammatory, antioxidant and antitussive properties. In this study, we investigated the effect of pruni cortex on atopic dermatitis NC/Nga mouse model. Atopic dermatitis-like lesion was induced by the application of house dust mite extract to the dorsal skin. After induction of atopic dermatitis, pruni cortex aqueous extract (1 g/kg, p.o.) was administered daily for 2 weeks. We evaluated dermatitis severity, histopathological changes and cellular protein expression by Western blotting for nuclear and cytoplasmic high mobility group box 1, receptor for advanced glycation end products, nuclear factor κB, apoptosis and inflammatory markers in the skin of atopic dermatitis mice. The clinical observation confirmed that the dermatitis score was significantly lower when treated with pruni cortex than in the atopic dermatitis group. Similarly pruni cortex inhibited hypertrophy and infiltration of inflammatory cells as identified by histopathology. In addition, pruni cortex significantly inhibited the protein expression of cytoplasmic high mobility group box 1, receptor for advanced glycation end products, nuclear p-nuclear factor kappa B, apoptosis and inflammatory markers. These results indicate that pruni cortex may have therapeutic potential in the treatment of atopic dermatitis by attenuating high mobility group box 1 and inflammation possibly through the nuclear factor κB pathway.
High mobility group box protein 1; inflammation; pruni cortex; nuclear factor κB; atopic dermatitis
A 24-week, double-blind, clinical trial of rabeprazole for the prevention of
recurrent peptic ulcers caused by low-dose aspirin (LDA) has been reported, but
trials for longer than 24 weeks have not been reported. The aim of this study is to
assess the long-term efficacy and safety of rabeprazole for preventing peptic ulcer
recurrence on LDA therapy. Eligible patients had a history of peptic ulcers on
long-term LDA (81 or 100 mg/day) therapy. Patients with no recurrence of
peptic ulcers at the end of the 24-week double-blind phase with rabeprazole (10- or
5-mg once daily) or teprenone (50 mg three times daily) entered the extension
phase. Rabeprazole doses were maintained for a maximum of 76 weeks, including the
double-blind 24-week period and the extension phase period (long-term rabeprazole 10-
and 5-mg groups). Teprenone was randomly switched to rabeprazole 10 or 5 mg for
a maximum of 52 weeks in the extension phase (newly-initiated rabeprazole 10- and
5-mg groups). The full analysis set consisted of 151 and 150 subjects in the
long-term rabeprazole 10- and 5-mg groups, respectively, and the cumulative
recurrence rates of peptic ulcers were 2.2 and 3.7%, respectively. Recurrent
peptic ulcers were not observed in the newly-initiated rabeprazole 10- and 5-mg
groups. No bleeding ulcers were reported. No clinically significant safety findings,
including cardiovascular events, emerged. The use of long-term rabeprazole 10- and
5-mg once daily prevents the recurrence of peptic ulcers in subjects on low-dose
aspirin therapy, and both were well-tolerated.
low-dose aspirin; peptic ulcer; bleeding ulcer; serious adverse events; rabeprazole
This study aimed to compare the nutritional status and energy expenditure of hospitalized patients with Crohn’s disease (CD) and those with ulcerative colitis (UC). Twenty-two hospitalized patients with CD and 18 patients with UC were enrolled in this study. We analyzed nutritional status upon admission by using nutritional screening tools including subjective global assessment, malnutrition universal screening tool, and laboratory tests. We measured resting energy expenditure (mREE) of the patients with indirect calorimetry and predicted resting energy expenditure (pREE) was calculated by using the Harris-Benedict equation. Results presented here indicate no significant difference in nutritional parameters and energy metabolism between CD and UC patients. In UC patients, a significant correlation was observed between mREE/body weight and disease activity detected by the Lichtiger and Seo indices. However, there was no correlation between mREE/body weight and Crohn’s disease activity index in CD patients. Inflammatory cytokine interleukin-6 levels correlated with mREE/pREE in CD and UC patients while tumor necrosis factor-α was not. In conclusion, energy expenditure significantly correlated with disease activity in UC patients but not in CD patients. These results indicate that establishing daily energy requirements based on disease activity of UC is imperative for improving the nutritional status of patients.
Crohn’s disease; ulcerative colitis; indirect calorimetry; energy metabolism; nutritional status
We investigated the changes in energy expenditure during induction therapy in patients with severe or moderate ulcerative colitis. Thirteen patients (10 men, 3 women; mean age, 36.5 years) with ulcerative colitis admitted to the Shiga University Hospital were enrolled in this study. We measured the resting energy expenditure and respiratory quotients of these patients before and after induction therapy with indirect calorimetry. We analyzed the changes of nutritional status and serum inflammatory cytokine levels and also evaluated the relationship between energy metabolism and disease activity by using the Seo index and Lichtiger index. The resting energy expenditure was 26.3 ± 3.8 kcal/kg/day in the active stage and significantly decreased to 23.5 ± 2.4 kcal/kg/day after induction therapy (p<0.01). The resting energy expenditure changed in parallel with the disease activity index and C-reactive protein and inflammatory cytokine levels. The respiratory quotient significantly increased after induction therapy. Thus, moderate to severe ulcerative colitis patients had a hyper-metabolic status, and the energy metabolism of these patients significantly changed after induction therapy. Therefore, we recommend that nutritional management with 30–34 kcal/kg/day (calculated as measured resting energy expenditure × activity factor, 1.3) may be optimal for hospitalized ulcerative colitis patients.
ulcerative colitis; indirect calorimetry; energy expenditure; respiratory quotient; induction therapy
Direct conversion of mammalian fibroblasts into induced neuronal (iN) cells has been attained by forced expression of pro-neural transcriptional factors, or by combining defined factors with either microRNAs or small molecules. Here, we show that neuronal cells can be converted from postnatal human fibroblasts into cell populations with neuronal purities of up to >80% using a combination of six chemical compounds. The chemical compound-induced neuronal cells (CiNCs) express neuron-specific proteins and functional neuron markers. The efficiency of CiNCs is unaffected by either the donor’s age or cellular senescence (passage number). We propose this chemical direct converting strategy as a potential approach for highly efficient generation of neuronal cells from human fibroblasts for such uses as in neural disease modeling and regenerative medicine.
direct conversion; human fibroblasts; neuronal cells; chemical compounds
Oral lichen planus is a chronic inflammatory disease that affects the mucous membrane of the oral cavity and can contribute to the development of other diseases. Inflammation in oral lichen planus is a T-cell-mediated autoimmune disease that acts through cytotoxic CD8+ T cells to trigger apoptosis of keratinocytes. However, the specific cause of oral lichen planus remains unknown and no effective medical treatment has yet been established. Astaxanthin is a carotenoid pigment with capacity for anti-inflammatory and anti-oxidant activities. In this study, we evaluated whether astaxanthin could be used to improve the pathology of oral lichen planus by reducing inflammation. In particular, the anti-inflammatory effects of astaxanthin on the chronic inflammation caused by lipopolysaccharide derived from Escherichia coli O55 in human gingival keratinocytes (NDUSD-1) were evaluated. Following astaxanthin treatment, localization of nuclear factor κB/p65 and the level of inflammatory cytokines (interleukin-6, tumor necrosis factor-α) tended to decrease, and cell proliferation significantly increased in vitro. These results suggest that astaxanthin could be useful for improving chronic inflammation such as that associated with oral lichen planus.
human gingival keratinocyte; chronic inflammation; astaxanthin; inflammatory cytokine; nuclear factor κB/p65
S-allyl cysteine (SAC) is the most abundant compound in aged garlic extracts (AGEs). AGE has been reported to ameliorate the oxidative damage implicated in a variety of diseases. However, the effects of SAC have not been established in liver cirrhosis. The aim of this study was to examine the effect of therapeutic administration of SAC in liver cirrhosis by chronic carbon tetrachloride (CCl4) administration in rats. SAC or other cysteine compounds were administered from 4 weeks when liver fibrosis was confirmed to be in process. CCl4 administration elevated plasma alanine aminotransferase, plasma lipid peroxidation, liver hydroxyproline, and liver transforming growth factor (TGF)-β at 12 weeks. SAC prevented these changes induced by CCl4. Furthermore, SAC improved survival in a dose-dependent manner following consecutive CCl4 administration. The inhibitory mechanisms may be associated with a decrease in the profibrogenic cytokine, TGF-β as well as the antioxidative properties of SAC.
aged garlic extracts; carbon tetrachloride; cirrhosis; S-allyl cysteine; TGF-β
Changes in l-arginine metabolism, including increased arginase levels and decreased nitric oxide production, are involved in the pathophysiology of asthma. In this study, using an intranasal mite-induced NC/Nga mouse model of asthma, we examined whether administration of l-arginine ameliorated airway hyperresponsiveness and inflammation by altering l-arginine metabolism. Experimental asthma was induced in NC/Nga mice via intranasal administration of mite crude extract (50 µg/day) on 5 consecutive days (days 0–4, sensitization) and on day 11 (challenge). Oral administration of l-arginine (250 mg/kg) was performed twice daily on days 5–10 for prevention or on days 11–13 for therapy. On day 14, we evaluated the inflammatory airway response (airway hyperresponsiveness, the number of cells in the bronchoalveolar lavage fluid, and the changes in pathological inflammation of the lung), arginase expression and activity, l-arginine bioavailability, and the concentration of NOx, the end products of nitric oxide. Treatment with l-arginine ameliorated the mite-induced inflammatory airway response. Furthermore, l-arginine administration attenuated the increases in arginase expression and activity and elevated the NOx levels by enhancing l-arginine bioavailability. These findings indicate that l-arginine administration may contribute to the improvement of asthmatic symptoms by altering l-arginine metabolism.
l-arginine; asthma; arginase; nitric oxide; l-arginine paradox
Diabetes is a metabolic disorder characterized by chronic hyperglycemia. Advanced diabetes is associated with severe complications and impaired nutritional status. Here, we assessed the expression of retinol-associated proteins, including β-carotene 15,15'-monooxygenase (BCMO), lecithin:retinol acyltransferase (LRAT), aldehyde dehydrogenase (ALDH), and cytochrome P450 26A1 (CYP26A1), and measured retinol levels in the plasma and liver of streptozotocin (STZ)-induced type 1 diabetic model rats. Compared to the levels in the control rats, retinol levels in the plasma and liver of STZ rats were decreased and increased, respectively. Hepatic expression of the LRAT gene in STZ rats was lower than that in the controls. In the liver of STZ rats, the expression of ALDH1A1, a retinal metabolizing enzyme was higher, whereas ALDH1A2 expression was lower than in the controls. Hepatic CYP26A1 expression in STZ rats was significantly higher than in the control rats. BCMO expression levels in the liver and intestine of STZ rats were much lower than those of the controls. Altered BCMO expression might affect retinol status. It is considered that the metabolic availability of retinol was lessened despite the accelerated catabolism of retinol; therefore, retinol mobilization may be unbalanced in the liver of rats in the type 1 diabetic state.
Type 1 diabetes; retinol; β-carotene 15,15'-monooxygenase; lecithin:retinol acyltransferase
In periodontitis, production of reactive oxygen species (ROS) by neutrophils induces oxidative stress and deteriorates surrounding tissues. Antioxidants reduce damage caused by ROS and are used to treat diseases involving oxidative stress. This study summarizes the different effects of resveratrol, quercetin, and N-acetylcysteine (NAC) on human gingival fibroblasts (HGFs) under oxidative stress induced by hydrogen peroxide. Real-time cytotoxicity analyses reveals that resveratrol and quercetin enhanced cell proliferation even under oxidative stress. Of the antioxidants tested, resveratrol is the most effective at inhibiting ROS production. HGFs incubated with resveratrol and quercetin up-regulate the transcription of type I collagen gene after 3 h, but only resveratrol sustained this up-regulation for 24 h. A measurement of the oxygen consumption rate (OCR, mitochondrial respiration) shows that resveratrol generates the highest maximal respiratory capacity, followed by quercetin and NAC. Simultaneous measurement of OCR and the extracellular acidification rate (non-mitochondrial respiration) reveals that resveratrol and quercetin induce an increase in mitochondrial respiration when compared with untreated cells. NAC treatment consumes less oxygen and enhances more non-mitochondrial respiration. In conclusion, resveratrol is the most effective antioxidant in terms of real-time cytotoxicity analysis, reduction of ROS production, and enhancement of type I collagen synthesis and mitochondrial respiration in HGFs.
human gingival fibroblasts; periodontitis; resveratrol; quercetin; N-acetylcysteine
Although recent studies have reported that Lactobacillus rhamnosus GG (LGG), the most extensively studied probiotic strain, exerts an anti-hyperglycemic effect on several rodent models, the underlying mechanism remains unclear. In this study, twenty male C57BL/KsJ-db/db (db/db) mice were divided into 2 groups, LGG-treated and control group, which received a daily dose of LGG (1 × 108 CFU per mouse) and PBS orally for 4 weeks, respectively. We observed that glucose tolerance was significantly improved in LGG-treated db/db mice. Insulin-stimulated Akt phosphorylation and GLUT4 translocation were higher in skeletal muscle of LGG-treated mice relative to their controls. It was also observed that LGG treatment caused significant reductions in endoplasmic reticulum (ER) stress in skeletal muscle and M1-like macrophage activation in white adipose tissues. Our results indicate that the anti-diabetic effect of LGG in db/db mice is associated with alleviated ER stress and suppressed macrophage activation, resulting in enhanced insulin sensitivity. These findings suggest a therapeutic potential of probiotics for prevention and treatment of type 2 diabetes.
probiotics; type 2 diabetic mice; insulin resistance; ER stress; M1-like macrophage activation