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PURPOSE: Probiotic Lactobacillus gasseri SBT2055 (LG2055) has an anti-obesity effect although it is unknown whether the effect influences inflammatory responses in adipose tissue and lipid metabolism in the liver, which are considered substantially relevant to adiposity. METHODS: C57BL/6 mice were fed a 10%-fat diet containing LG2055 cells for 24 weeks. We then studied body weight, fat tissue mass, liver fat content and inflammatory genes in the adipose tissue, and lipogenic and lipolytic genes in the liver. RESULTS: Consumption of LG2055 resulted in a significant reduction in body weight and fat tissue mass (epididymal and perirenal/retroperitoneal), with a lowered level of triglyceride content in the liver. DNA microarray analysis showed that LG2055 generally inhibited the up-regulation of pro-inflammatory genes, including CCL2 and CCR2, in the epididymal adipose tissue. In the liver, LG2055 tended to inhibit lipogenic gene up-regulation, including ACC1, FAS and SREBP1, but LG2055 did not markedly alter lipolytic genes. Real-time PCR analysis confirmed the DNA microarray results in part, showing a significant reduction in the mRNA expression of CCL2 in the epididymal adipose tissue, and a downward tendency in FAS mRNA expression in the liver, in the LG2055-fed group. CONCLUSIONS: LG2055 significantly prevented body weight gain, fat accumulation and pro-inflammatory gene expression in the adipose tissue. Relatively lower triglyceride levels and reduced expression of lipogenic genes were also observed in the liver. It is suggested that improvement in the inflammatory state of the adipose tissue might be a possible mechanism underlying the anti-obesity effect of LG2055.
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Regulação da Expressão Gênica , Inflamação/genética , Gordura Intra-Abdominal/metabolismo , Lactobacillus/fisiologia , Obesidade/terapia , Probióticos/uso terapêutico , Adiposidade , Animais , Composição Corporal , Peso Corporal , Quimiocina CCL2/genética , Dieta , Gorduras na Dieta/administração & dosagem , Epididimo , Ácido Graxo Sintases/genética , Metabolismo dos Lipídeos/genética , Fígado/química , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , Triglicerídeos/análiseRESUMO
Background: The effects of dietary patterns on health outcome of lactating women remain unclear. Objectives: To describe the dietary patterns of lactating Japanese women and explore the association between dietary patterns and their general health. Methods: This study included 1096 lactating women from the Japanese Human Milk Study Cohort. The maternal diet during lactation 1-2 mo postpartum was determined using a FFQ. Dietary patterns were identified using a factor analysis based on the energy-adjusted intake of 42 food items. Trend associations between maternal and infant variables and quartiles of dietary pattern scores were tested, and logistic regression was performed to estimate the OR and 95% CI of maternal self-reporting anemia, constipation, rough skin, sensitivity to cold, and mastitis. Results: Four dietary patterns were identified in this study. The versatile vegetable diet, characterized by a high intake of vegetables, mushrooms, seaweeds, and tofu, was associated with maternal age, BMI prepregnancy and during the lactation periods, education, household income, and anemia. The plain Japanese diet contained a high intake of typical Japanese foods such as rice and miso soup and a low intake of bread and some confectioneries and was associated with maternal BMI during both periods. The salad vegetable diet, characterized by a high intake of raw vegetables and tomatoes with mayonnaise or dressing, was associated with parity and season in which data collection was conducted. The seafood diet, characterized by a high intake of fish, squid, octopus, shrimp, and shellfish, was associated with days postpartum and sensitivity to cold. Conclusions: Four dietary patterns were identified and were independently associated with socioeconomic factors. The versatile vegetables diet and seafood diet were associated with anemia and sensitivity to cold, respectively, among the participants. This trial was registered at the Japanese Clinical Trials Registry (https://center6.umin.ac.jp/cgi-open-bin/icdr_e/ctr_view.cgi?recptno=R000017649) as UMIN000015494.
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The causality and mechanism of dietary effects on brain aging are still unclear due to the long time scales of aging. The nematode Caenorhabditis elegans has contributed to aging research because of its short lifespan and easy genetic manipulation. When fed the standard laboratory diet, Escherichia coli, C. elegans experiences an age-dependent decline in temperature-food associative learning, called thermotaxis. To address if diet affects this decline, we screened 35 lactic acid bacteria as alternative diet and found that animals maintained high thermotaxis ability when fed a clade of Lactobacilli enriched with heterofermentative bacteria. Among them, Lactobacillus reuteri maintained the thermotaxis of aged animals without affecting their lifespan and motility. The effect of Lb. reuteri depends on the DAF-16 transcription factor functioning in neurons. Furthermore, RNA sequencing analysis revealed that differentially expressed genes between aged animals fed different bacteria were enriched with DAF-16 targets. Our results demonstrate that diet can impact brain aging in a daf-16-dependent manner without changing the lifespan.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Envelhecimento/fisiologia , Longevidade/fisiologia , Dieta , Escherichia coli/fisiologia , Fatores de Transcrição Forkhead/genéticaRESUMO
Background: Maternal diet and sociodemographic factors influence xanthophyll concentration and composition in human milk. However, the importance of dietary patterns regarding the intake of fruits, vegetables, and xanthophylls remains unclear. Objective: The aim was to determine the composition of xanthophylls in the human milk of Japanese mothers and explore associations of xanthophylls with dietary and sociodemographic factors. Methods: This cross-sectional study was conducted in the early phase of the Japanese Human Milk Study. Xanthophyll content was measured using liquid chromatography at 30-36 d postpartum. Maternal intake of foods, nutrients, and dietary supplements was estimated using a food-frequency questionnaire. Linear regression models were established using xanthophylls, maternal diet, and sociodemographic factors. Results: Xanthophyll concentrations were measured in human milk from 118 mothers. The xanthophyll concentration varied among individuals. The median (IQR) concentrations of lutein, zeaxanthin, and ß-cryptoxanthin were 65.6 ng/mL (51.6-103.4 ng/mL), 18.6 ng/mL (12.9-25.8 ng/mL), and 15.6 ng/mL (9.0-26.0 ng/mL), respectively. In multivariate models, the lutein concentration was associated independently with dietary green vegetables, exclusive breastfeeding, and education (r 2 = 0.153 for the model; ß ± SE: 0.468 ± 0.198, 25.048 ± 10.222, and 13.460 ± 6.774; standardized ß = 0.210, 0.217, and 0.175; P = 0.019, 0.016, and 0.049 for dietary green vegetables, exclusive breastfeeding, and education, respectively). For zeaxanthin, exclusive breastfeeding was the most appropriate predictor (r 2 = 0.085; ß ± SE: 7.811 ± 3.300; standardized ß = 0.218; P = 0.020). The highest predictive power for human milk ß-cryptoxanthin was obtained with dietary ß-cryptoxanthin (r 2 = 0.258; ß ± SE: 0.089 ± 0.015; standardized ß = 0.468; P < 0.001), attributed to maternal citrus intake. Conclusions: ß-Cryptoxanthin in human milk was the xanthophyll most influenced by the maternal diet in Japanese women. The ß-cryptoxanthin concentration in human milk was reflected by the maternal ß-cryptoxanthin intake, mainly attributed to Japanese citrus consumption. This trial was registered in the Japanese Clinical Trials Registry (https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000017649) as UMIN000015494.
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This study investigated whether parenting stress is associated with breastfeeding type (exclusive or partial). Between 2014 and 2019, we recruited 1210 healthy mothers (mean age, 31.2 years; 65%, multiparity) from 73 obstetric institutions across all prefectures of Japan. Among these, 1120 mothers at two months and 1035 mothers at six months were investigated for parenting stress and breastfeeding type: exclusive versus otherwise (partial). Parenting stress was measured by a validated Japanese scale consisting of childcare exhaustion, worry about child's development, and no partner support. Exclusive breastfeeding prevalence was 75% at two and 78% at six months. The total scores for childcare exhaustion and worry about child development were statistically higher in the partial breastfeeding group than in the exclusive breastfeeding group at two months but not at six months. A logistic regression model demonstrated that childcare exhaustion was significantly associated with an increased risk of having partial breastfeeding at two months after adjusting for the maternal Body Mass Index, parity, and baby's current weight. However, the association was no longer significant at six months. The present study suggests that intervention for parenting stress at two months postpartum may promote prolonged exclusive breastfeeding.
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Aleitamento Materno , Cuidado da Criança , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Lactente , Japão , Mães , GravidezRESUMO
Cry toxins have been reported to bind not only to receptors on insect cells but also to several unrelated proteins. In this study, we investigated the binding properties of Bacillus thuringiensis Cry toxins, focusing on domain III, a Cry toxin region with a structure that of the galactose-binding domain-like. Cry1Aa, Cry1Ac, and Cry8Ca specifically bound to several proteins unrelated to insect midgut cells. Cry1Aa binding to Cry toxin-binding proteins was inhibited by a monoclonal antibody, 2C2, indicating that Cry1Aa binds to these Cry toxin-binding proteins through domain III. Cry1Aa binding to Bombyx mori aminopeptidase N and other Cry toxin-binding proteins was inhibited by carbonic anhydrase, a Cry toxin-binding protein. The binding regions of carbonic anhydrase and Bombyx mori aminopeptidase N were narrowed to regions of less than 20 amino acids that did not have any similarity, suggesting that Cry toxin domain III has a binding pocket for multiple proteins.
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Bacillus thuringiensis , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Galactose/metabolismo , Acetilgalactosamina/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Toxinas de Bacillus thuringiensis , Bombyx/enzimologia , Antígenos CD13/química , Antígenos CD13/metabolismo , Anidrases Carbônicas/farmacologia , Bovinos , Endotoxinas/química , Endotoxinas/metabolismo , Eritrócitos/enzimologia , Proteínas Hemolisinas/química , Proteínas Hemolisinas/metabolismo , Indicadores e Reagentes/metabolismo , Proteínas de Insetos/metabolismo , Ligantes , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Especificidade por SubstratoRESUMO
To characterize the milk phospholipids (PLs) profile using phosphorus-31 nuclear magnetic resonance (31P-NMR) and to investigate the effect of elevated milk docosahexaenoic acid (DHA) levels on PLs profiles in Japanese mothers. Methods: Milk samples from eligible patients with high and low DHA from a former cross-sectional study (n = 20; n = 10 for each group) were included. Fifteen milk PLs were analyzed using 31P-NMR, and the profiles were compared group-wise using Mann-Whitney U-test. The P value of <0.05 was considered statistically significant. Results: The median DHA content in milk was 1.13% and 0.29% for the high and low milk DHA groups, respectively. Twelve PLs, excluding lysophosphatidylserine, cardiolipin, and phosphatidylglycerol, were detected in all participants with 100% positive results. The median concentrations and proportions of total PLs, sphingophospholipids, and glycerophospholipids were comparable between groups. The proportions of choline-containing glycerophospholipid were significantly higher in the high milk DHA group than that in the low milk DHA group (24.09% [median, interquartile range: 23.08%-26.38%] and 21.41% [20.74%-22.84%], P = 0.019). Although the proportions of phosphatidylinositol were significantly lower in the high milk DHA group than that in the low milk DHA group (6.62% [5.75%-6.72%] versus 7.63% [7.11%-8.16%], P = 0.002), while that of phosphatidylcholine (21.90% [18.51%-23.22%] versus 19.78% [18.17%-20.26%], P = 0.059) and alkyl-acyl phosphatidylcholine (0.60% [0.40%-0.74%] versus 0.33% [0.14%-0.51%], P = 0.059) were higher in the former than that in the latter. Conclusions: Our results were comparable to that of the previous literature. Large variations in the milk DHA might affect the composition of choline-containing glycerophospholipids in Japanese mothers. However, possible confounders were not excluded in the study populations.
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PURPOSE: The Japanese Human Milk Study, a longitudinal prospective cohort study, was set up to clarify how maternal health, nutritional status, lifestyle and sociodemographic and economic factors affect breastfeeding practices and human milk composition. This would eventually determine factors affecting the growth and development of infants and children. PARTICIPANTS: A total of 1210 Japanese lactating women who satisfied the inclusion criteria, were invited across the country at various participating sites, between 2014 and 2019. Finally a total of 1122 women were enrolled in this study. FINDINGS TO DATE: Among 1122 eligible participants, mean age at delivery was 31.2 (SD 4.4) years and mean prepregnancy BMI was 20.8 (SD 2.7). Among these women, 35% were previously nulliparous and 77.7% had college, university or higher education. The mean gestational period was 39.0 (SD 1.3) weeks. Caesarean section was reported among 11.9%; mean infant birth weight was 3082 (SD 360) g. Of the infants, 53.7% were male. Overall, our participants appeared to be healthier than the general population in Japan. Analyses of the 1079 eligible human milk samples obtained at the first and second months postpartum showed the following composition: carbohydrate, 8.13 (SD 0.32) g/100 mL; fat, 3.77 (SD 1.29) g/100 mL; and crude protein, 1.20 (SD 0.23) g/100 mL. We also analysed osteopontin, fatty acid, vitamin D and phospholipid levels in limited subcohorts of the samples. FUTURE PLANS: Follow-up surveys will be conducted to obtain milk samples every 2 months for 12 months and to investigate mother and child health until the children reach 5 years of age. These will be completed in 2024. We plan to longitudinally analyse the composition of macronutrients and various bioactive factors in human milk and investigate the lifestyle and environmental factors that influence breastfeeding practices, maternal and child health, and child development. TRIAL REGISTRATION NUMBER: UMIN000015494; pre-results.
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Leite Humano , Osteopontina , Lactente , Criança , Humanos , Masculino , Feminino , Gravidez , Leite Humano/metabolismo , Estudos Prospectivos , Osteopontina/metabolismo , Japão/epidemiologia , Lactação , Cesárea , Aleitamento Materno , Estudos de Coortes , Nutrientes , Vitamina D/metabolismo , Ácidos Graxos , Carboidratos , Fosfolipídeos/metabolismoRESUMO
BACKGROUND: Breast milk is considered the optimal source of nutrition during infancy. Although the vitamin D concentration in human breast milk is generally considered poor for infants, vitamin D in breast milk is an important source for exclusively breastfed infants. Increases in vitamin D insufficiency and deficiency in lactating mothers may reduce vitamin D concentrations in breast milk. This study aimed to compare vitamin D and 25-hydroxyvitamin D (25OHD) concentrations in breast milk collected in 1989 and 2016-2017 and simultaneously analyze them with liquid chromatography-tandem mass spectrometry (LC-MS/MS); the association between the lifestyle of recent lactating mothers (2016-2017) and vitamin D status in human breast milk was also evaluated. METHOD: Lactating mothers were recruited from three regions of Japan in 1989 (n = 72) and 2016-2017 (n = 90), and milk from 3-4 months was collected in summer and winter. The samples were strictly sealed and stored at -80â until measurement. Breast milk vitamin D and 25OHD concentrations were analyzed by LC-MS/MS. Vitamin D intake, sun exposure, and sunscreen use of the lactating mothers in 2016-2017 were assessed. RESULTS: Both vitamin D and 25OHD concentrations in breast milk were higher in the summer regardless of the survey year. Significantly lower vitamin D and 25OHD concentrations were observed in 2016-2017 compared with 1989 in summer, but no survey year difference was observed in winter. The stepwise multiple regression analyses identified season, daily outdoor activity, and suntan in the last 12 months as independent factors associated with vitamin D3 concentrations. CONCLUSION: The results suggest that low vitamin D status in recent lactating mothers may have decreased vitamin D and 25OHD concentrations in breast milk compared with the 1980s. These results are helpful for developing public health strategies to improve vitamin D status in lactating mothers and infants.
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Leite Humano/química , Vitamina D/análogos & derivados , Vitamina D/análise , Adulto , Colecalciferol/análise , Feminino , Humanos , Lactente , Japão , Lactação , Estilo de Vida , Estado Nutricional , Estações do Ano , Luz Solar , Fatores de Tempo , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/prevenção & controleRESUMO
BACKGROUND: DHA (22:6n-3) is essential for neurodevelopment in children, and its concentration in human breast milk is historically high in Japan. Dietary patterns in Japan might affect the fatty acid (FA) composition among lactating mothers. OBJECTIVES: This study aimed to characterize the composition of milk FAs and to identify any dietary and sociodemographic factors associated with the variability of DHA concentration in breast milk in the Japanese population. METHODS: This cross-sectional study was performed as part of the Japanese Human Milk Study. Milk FAs were analyzed by GC at 1-6 mo postpartum, and maternal diet was estimated using an FFQ, including 11 types and cooking methods of seafoods, and the use of DHA supplements. The association of milk DHA with maternal diet and sociodemographic factors was investigated. RESULTS: Milk FA concentrations were measured in 78 mothers, including 24 who routinely used DHA supplements. The DHA concentration in milk (overall median: 0.62%; IQR: 0.47%-0.78%) was higher in women who took DHA supplements than in women who had never used DHA supplements (0.74%compared with 0.55%; P = 0.011). A linear regression model showed the association of milk DHA concentration with maternal dietary intake of grilled fish (ß ± SE: 0.006 ± 0.003; standardized ß: 0.234; r 2 = 0.232, P = 0.036) after adjustment for DHA supplementation status, maternal and infant age, maternal BMI, and infant birth weight. Other FA concentrations were consistent, whereas caproic acid (6:0), undecylic acid (11:0), pentadecylic acid (15:0), palmitoleic acid (16:1n-7), and vaccenic acid (18:1n-7) varied by DHA supplementation status. CONCLUSIONS: The DHA concentration in human milk may be influenced by maternal grilled fish consumption and frequent DHA supplementation in lactating Japanese women. Milk DHA concentrations may reflect a dietary habit in Japanese mothers.This trial was registered at www.umin.ac.jp/ctr as UMIN000015494.
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It is unknown whether maternal health and nutrition are related to human milk composition or growth and development of infants and children. Here, we describe a protocol for a prospective five-year cohort study to clarify (i) how maternal health and nutrition, socioeconomic factors, and lifestyles affect human milk composition, and (ii) whether these are associated with growth and development of infants and children. In our study, we recruited 1210 Japanese mothers with singleton pregnancies from 73 obstetrics clinics and hospitals across Japan, between 2014 and 2019. We will measure the following: health information regarding maternal-child dyads using a self-administered questionnaire, maternal nutrition during breastfeeding using a Brief self-administrated Diet History Questionnaire, the development of infants and children using the Kinder Infant Development Scale, and the stress related to child rearing using the Mother's Child Care Stress Scale. Simultaneously, we will collect human milk every 2 months during the first year after birth to measure its composition and levels of macronutrients. This study will generate useful data to investigate whether health status, nutritional status, lifestyle, and socioeconomic factors affect human milk composition and the growth and development of infants and children.
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Aleitamento Materno , Leite Humano , Estado Nutricional , Criança , Estudos de Coortes , Feminino , Humanos , Lactente , Japão , Saúde Materna , Gravidez , Estudos ProspectivosRESUMO
Binding analyses with denatured epithelial membrane proteins from Bt (Bacillus thuringiensis) demonstrated at least two kinds of proteins, APNs (aminopeptidases N) and cadherin-like proteins, as possible receptors for the Cry1A class of Bt toxins. Two alternative models have been proposed, both based on initial toxin binding to a cadherin-like protein, but one involving APN and the other not. We have used two Bombyx mori strains (J65 and Kin), which are highly susceptible to Cry1Ab, to study the role of these two types of receptors on Cry1Ab toxin binding and cytotoxicity by means of the inhibitory effect of antibodies. BBMVs (brush-border membrane vesicles) of strain J65 incubated with labelled 125I-Cry1Ab revealed a marked reduction in reversible and irreversible binding when anti-BtR175 (a cadherin-like protein) was used for BBMV pre-treatment. By contrast, the anti-APN1 antibody specifically affected the irreversible binding, while the reversible binding component was not affected. This is the first time that binding of Cry1Ab to APN1 and to a cadherin-like protein from BBMVs in solution has been shown. Dissociated epithelial cells from the Kin strain were used to test the inhibitory effect of the antibodies on the cytotoxicity of Cry1Ab. Pre-incubation of the cells with the anti-BtR175 antibody conferred protection against Cry1Ab, but not the anti-APN1 antibody. Therefore our results seem to support the two models of the mode of action of Cry1Ab in Lepidoptera, depending on whether BBMVs or intact dissociated cells are used, suggesting that both pathways may co-operate for the toxicity of Cry1A toxins in vivo.
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Aminopeptidases/química , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Toxinas Bacterianas/antagonistas & inibidores , Toxinas Bacterianas/química , Endotoxinas/antagonistas & inibidores , Endotoxinas/química , Proteínas Hemolisinas/antagonistas & inibidores , Proteínas Hemolisinas/química , Membranas/metabolismo , Animais , Anticorpos/química , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Bioensaio , Bombyx , Antígenos CD13/química , Endotoxinas/metabolismo , Células Epiteliais/metabolismo , Proteínas Hemolisinas/metabolismo , Mucosa Intestinal/metabolismo , Microvilosidades/metabolismo , Ligação ProteicaRESUMO
Aminopeptidase N (APN) and cadherin-like protein (BtR175) from Bombyx mori larvae were examined for their roles in Cry1Aa- and Cry1Ac-induced lysis of B. mori midgut epithelial cells (MECs). APNs and BtR175 were present in all areas of the midgut, were particularly abundant in the posterior region, and were found only on columnar cell microvilli and not on the lateral membrane that makes cell-cell contacts. This distribution was in accordance with the distribution of Cry1A-susceptible MECs in the midgut. The lytic activity of Cry1Aa and Cry1Ac on collagenase-dissociated MECs was linearly dependent on toxin concentration. Although pre-treatment of MECs with anti-BtR175 antibody was observed to partially inhibit the lytic activity exerted by 0.1-1 nM Cry1Aa toxin or 5 nM Cry1Ac toxin, no significant inhibition was observed when MECs were pre-treated with anti-APN antibody. These results suggest that BtR175 functions as a major receptor for Cry1A toxins in the midgut of B. mori larvae.
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Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas , Bombyx/metabolismo , Caderinas/metabolismo , Endotoxinas/metabolismo , Proteínas de Insetos , Larva/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Toxinas de Bacillus thuringiensis , Sequência de Bases , Bombyx/crescimento & desenvolvimento , Primers do DNA , Células Epiteliais/metabolismo , Proteínas Hemolisinas , L-Lactato Desidrogenase/metabolismoRESUMO
We examined the role of carotenoid-binding protein (CBP) in yellow cocoon pigmentation. First, using yellow or white cocoon races, we investigated the linkage between the yellow pigmentation and CBP expression. CBP was expressed only in the silk gland of the yellow cocoon races, which utilize carotenoids for cocoon pigmentation. Furthermore, CBP expression in the silk glands of day 1-7 fifth instar larvae matched the period of carotenoid uptake into the silk gland. Finally, we gave double-stranded CBP RNA to Bombyx mori (B. mori) larvae to induce RNA interference. The significantly reduced expression of CBP in the silk gland of fifth instar larva was confirmed on day 4 and a decrease in yellow pigmentation was observed in the cocoon. We showed that CBP plays a key role in the yellow cocoon pigmentation caused by carotenoids.
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Bombyx/fisiologia , Carotenoides/metabolismo , Proteínas de Transporte/fisiologia , Proteínas de Insetos/fisiologia , Pigmentação/fisiologia , Animais , Bombyx/genética , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Sistema Digestório/metabolismo , Glândulas Exócrinas/metabolismo , Immunoblotting , Proteínas de Insetos/biossíntese , Proteínas de Insetos/genética , Larva/fisiologia , Interferência de RNA , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/farmacologiaRESUMO
There are two types of brown adipocytes: classical brown adipocytes that form the brown fat depots and beige adipocytes that emerge in the white fat depots. Beige adipocytes have a low level of uncoupling protein 1 (Ucp1) expression in the basal state, but Ucp1 expression is increased in response to ß adrenergic receptor activation. The present study explored the factors responsible for the differentiation of 3T3-L1 white preadipocytes to beige adipocytes. Significant expression of Ucp1 was not detected under any tested conditions in the absence of isoproterenol (Iso), an agonist of ß adrenergic receptor. Iso-induced Ucp1 expression was significantly higher in the cells treated with a mixture of triiodothyronine (T3) and 3-isobutyl-1-methylxanthine (IBMX) for days 0-8 than in the control cells. Chronic IBMX treatment was indispensable for the enhanced Iso-induced Ucp1 expression, and treatment with additional rosiglitazone (Rosi) for days 0-8 further increased the Ucp1 expression. Recently, genes were identified that are predominantly expressed in beige adipocytes, which were induced from stromal vascular cells in white fat depots. However, the expression levels of the beige adipocyte-selective genes in the adipocytes induced by the mixture of T3, IBMX and Rosi did not differ from those in the control adipocytes. The present study indicates that 3T3-L1 cells can differentiate to beige-like adipocytes by prolonged treatment with the mixture of T3, IBMX and Rosi and that the gene expression profile of the adipocytes is distinct from those previously induced from white fat depots.
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1-Metil-3-Isobutilxantina/farmacologia , Adipócitos Brancos/citologia , Diferenciação Celular/fisiologia , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Tiazolidinedionas/farmacologia , Tri-Iodotironina/farmacologia , Células 3T3-L1 , Adipócitos Brancos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Camundongos , RNA/química , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Rosiglitazona , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína Desacopladora 1RESUMO
BACKGROUND: We previously reported that dietary sphingomyelin (SM) concentrate from bovine milk improves epidermal functions. SM is a known precursor of ceramide (Cer) in the stratum corneum (SC). Neither the uptake nor distribution of orally administered SM nor its effects on epidermal functions have been demonstrated. OBJECTIVE: We evaluated the effects of dietary SM on epidermal functions, and the distribution and fate of its radiolabeled metabolites in mice orally administered [4,5-(3)H-sphinganyl] sphingomyelin ((3)H-SM). METHODS: Bovine milk SM (98% purity) was administered orally to 13-week-old hairless mice at 142 mg/kg per day for eight weeks. Their SC hydration, transepidermal water loss (TEWL), and SC Cer content were measured. (3)H-SM was then administered orally to 10-week-old hairless mice. Its distribution and metabolites in the skin were evaluated with whole-body autoradiography, liquid scintillation counting, and thin-layer chromatography. RESULTS: SC hydration in the SM-administered mice was higher than that in control mice, whereas their TEWL and Cer contents did not differ. Radioactivity was distributed extensively in the bodies of the experimental mice and decreased gradually with time. In contrast, the radioactivity in the SC remained constant after its administration, and radiolabeled SM and Cer were detected in the skin. This suggests that dietary SM is transferred to the skin and then converted to Cer in the SC. CONCLUSIONS: Orally administered SM is incorporated into skin SM and converted to SC Cer, which is involved in the water-holding capacity of the SC.