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1.
Sci Rep ; 13(1): 11229, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37433837

RESUMO

Bisphenol F (BPF) is replacing Bisphenol A (BPA) in the manufacture of products due to endocrine-disrupting effects. BPF monomers can also be released into the environment and enter the food chain, resulting in human exposure to low doses. Since bisphenols are primarily metabolized by the liver, this organ is more vulnerable to lower doses of bisphenols than others. Exposure during prenatal development may increase the risk of diseases in adulthood. The aim was to evaluate whether BPF administration could generate oxidative stress in liver of lactating rats, and whether these effects may be also observed in female and male postnatal day 6 (PND6) offspring. Long Evans rats received oral treatment: Control, BPF-low-dose (LBPF) 0.0365 mg/kg b.w./day, and BPF-high-dose (HBPF) 3.65 mg/kg b.w./day. The levels of antioxidant enzymes (CAT, SOD, GR, GPx and GST), glutathione system (GSH, GSSG) and lipid damage markers (MDA, LPO) were measured using colorimetric methods in liver of both lactating dams and in PND6 offspring. Mean values were analyzed using Prism-7. LBPF affected liver defense mechanisms (antioxidant enzymes and glutathione system), increasing ROS levels and producing lipid peroxidation in lactating dams. Similar effects were found in female and male PND6 offspring as a consequence of perinatal exposure.


Assuntos
Antioxidantes , Lactação , Humanos , Gravidez , Feminino , Masculino , Ratos , Animais , Ratos Long-Evans , Fígado , Estresse Oxidativo , Glutationa
2.
Med Oral Patol Oral Cir Bucal ; 24(5): e652-e658, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31433388

RESUMO

BACKGROUND: The aim of this study was to assess the effect of local application of IGF-I on osseointegration of dental implants placed in osteoporotic bones. MATERIAL AND METHODS: 16 rabbits were randomly distributed into two groups: eight animals were ovariectomized and fed a low-calcium diet for six weeks, in order to induce experimental osteoporosis, and the others were sham-operated and fed a standard diet. A titanium implant was inserted into the tibiae in both groups. In half of the rabbits, 4 µg of IGF-I was applied into the ostectomy, prior to the implant insertion. A total of 32 implants were placed. Animals were sacrificed two weeks after surgery and decalcified samples were processed for Bone-To-Implant Contact (BIC) and Bone Area Density (BAD) measurements. Analysis of variance (ANOVA) was used for statistical evaluation. P<0.05 was considered to be significant. RESULTS: Ovariectomy induced statistically significant lower BAD values (p=0.008) and a tendency towards lower BIC values when compared osteoporotic and healthy groups. The administration of 4 µg of IGF-I did not produce statistically significant differences neither on BIC nor on BAD values, neither in the osteoporotic animals nor in healthy. CONCLUSIONS: Within the limitations of this experimental study, local administration of 4 µg of IGF-I was not able to induce any changes in the osseointegration process two weeks after surgery, neither in healthy rabbits nor in the osteoporotic group.


Assuntos
Implantes Dentários , Osteoporose , Animais , Densidade Óssea , Feminino , Humanos , Fator de Crescimento Insulin-Like I , Osseointegração , Coelhos , Titânio
3.
Exp Gerontol ; 73: 114-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26581911

RESUMO

Inflammation is related to several pathological processes. The aim of this study was to investigate the protein expression of the different subunits of the nuclear factor Kappa b (NFkBp65, p50, p105, p52, p100) and the protein expressions of IkB beta and alpha in the hearts from a murine model of accelerated aging (SAM model) by Western blot. In addition, the translocation of some isoforms of NFkB from cytosol to nuclei (NFkBp65, p50, p52) and ATP level content was studied. In addition we investigated the effect of the chronic administration of growth hormone (GH) on these age-related parameters. SAMP8 and SAMR1 mice of 2 and 10 months of age were used (n = 30). Animals were divided into five experimental groups: 2 old untreated (SAMP8/SAMR1), 2 young control (SAMP8/SAMR1) and one GH treated-old groups (SAMP8). Age-related changes were found in the studied parameters. We were able to see decreases of ATP level contents and the translocation of the nuclear factor kappa B p50, p52 and p65 from cytosol to nuclei in old SAMP8 mice together with a decrease of IKB proteins. However p100 and p105 did not show differences with aging. No significant changes were recorded in SAMR1 animals. GH treatment showed beneficial effects in old SAMP8 mice inducing an increase in ATP levels and inhibiting the translocation of some NFkB subunits such as p52. Our results supported the relation of NFkB activation with enhanced apoptosis and pro-inflammatory status in old SAMP8 mice and suggested a selective beneficial effect of the GH treatment, which was able to partially reduce the incidence of some deleterious changes in the heart of those mice.


Assuntos
Senilidade Prematura/metabolismo , Hormônio do Crescimento/farmacologia , Quinase I-kappa B/metabolismo , Miocárdio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Senilidade Prematura/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Núcleo Celular/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Hormônio do Crescimento/uso terapêutico , Coração/efeitos dos fármacos , Masculino , Camundongos Endogâmicos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Isoformas de Proteínas/metabolismo , Quinase Induzida por NF-kappaB
4.
Biogerontology ; 17(2): 325-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26415859

RESUMO

The senescence- accelerated mouse prone 8 (SAMP8) is a well- characterized animal model of senescence that shows early age- related neurodegeneration with impairment in learning and memory skills when compared with control senescence- resistant mice (SAMR1). In the current study, we investigated whether such impairment could be partly due to changes in mitochondrial DNA (mtDNA) repair capacity and mitochondrial DNA damage in the brain of SAMP8 mice. Besides we studied whether these potential changes were related to modifications in two major processes likely involved in aging and neurodegeneration: apoptosis and inflammation. We observed that the specific activity of one of the main mtDNA repair enzymes, the mitochondrial APE1, showed an age- related reduction in SAMP8 animals, while in SAMR1 mice mitochondrial APE1 increased with age. The reduction in mtAPE1 activity in SAMP8 animals was associated with increased levels of the DNA oxidative damage marker 8oxodG in mtDNA. Our results also indicate that these changes were related to a premature increase in apoptotic events and inflammation in the brain of SAMP8 mice when compared to SAMR1 counterparts. We suggest that the premature neurodegenerative phenotype observed in SAMP8 animals might be due, at least in part, to changes in the processing of mtDNA oxidative damage, which would lead to enhancement of apoptotic and inflammatory processes.


Assuntos
Envelhecimento/metabolismo , Apoptose , Dano ao DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Inflamação/patologia , Animais , Biomarcadores/metabolismo , Encéfalo/metabolismo , DNA Mitocondrial , Camundongos
5.
QJM ; 107(8): 603-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24970762

RESUMO

Previous contributions to Quarterly Journal of Medicine have drawn attention to the work of FEAM, the Federation of European Academies of Medicine, in collaboration with others, in exploring and explaining the issues that will ensure an appropriate European Union (EU) policy framework for health research and innovation. In this article, we present a proposal for an archive of important research conducted in the EU that will act as a resource for illustrating and guiding the development of the necessary regulatory framework.


Assuntos
Pesquisa Biomédica/organização & administração , Academias e Institutos , Pesquisa Biomédica/legislação & jurisprudência , União Europeia , Política de Saúde , Humanos
6.
J Gerontol A Biol Sci Med Sci ; 69(10): 1186-98, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24300031

RESUMO

The aim of our study was to elucidate the role of growth hormone (GH) replacement therapy in three of the main mechanisms involved in sarcopenia: alterations in mitochondrial biogenesis, increase in oxidative stress, and alterations in protein balance. We used young and old Wistar rats that received either placebo or low doses of GH to reach normal insulin-like growth factor-1 values observed in the young group. We found an increase in lean body mass and plasma and hepatic insulin-like growth factor-1 levels in the old animals treated with GH. We also found a lowering of age-associated oxidative damage and an induction of antioxidant enzymes in the skeletal muscle of the treated animals. GH replacement therapy resulted in an increase in the skeletal muscle protein synthesis and mitochondrial biogenesis pathways. This was paralleled by a lowering of inhibitory factors in skeletal muscle regeneration and in protein degradation. GH replacement therapy prevents sarcopenia by acting as a double-edged sword, antioxidant and hypertrophic.


Assuntos
Antioxidantes/farmacologia , Hormônio do Crescimento/uso terapêutico , Terapia de Reposição Hormonal , Músculo Esquelético/metabolismo , Proteínas/metabolismo , Sarcopenia/prevenção & controle , Envelhecimento/metabolismo , Animais , Composição Corporal , Hormônio do Crescimento/farmacologia , Masculino , Mitocôndrias Musculares/fisiologia , Ratos , Ratos Wistar
7.
Biogerontology ; 14(4): 431-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23852044

RESUMO

It has been suggested that the age-related decrease in the number of neurons in the hippocampus that leads to alterations in brain function, may be associated with an increase in apoptosis due to the reduced secretion of growth hormone (GH) and/or melatonin in old animals. In order to investigate this possibility, male Wistar rats of 22 months of age were divided into three groups. One group remained untreated and acted as the control group. The second was treated with growth hormone (hGH) for 10 weeks (2 mg/kg/d sc) and the third was subjected to melatonin treatment (1 mg/kg/d) in the drinking water for the same time. A group of 2-months-old male rats was used as young controls. All rats were killed by decapitation at more than 24 month of age and dentate gyri of the hippocampi were collected. Aging in the dentate gyrus was associated with an increase in apoptosis promoting markers (Bax, Bad and AIF) and with the reduction of some anti-apoptotic ones (XIAP, NIAP, Mcl-1). Expressions of sirtuin 1 and 2 (SIRT1 and 2) as well as levels of HSP 70 were decreased in the dentate gyrus of old rats. GH treatment was able to reduce the pro/anti-apoptotic ratio to levels observed in young animals and also to increase SIRT2. Melatonin reduced also expression of pro-apoptotic genes and proteins (Bax, Bad and AIF), and increased levels of myeloid cell leukemia-1 proteins and SIRT1. Both treatments were able to reduce apoptosis and to enhance survival markers in this part of the hippocampus.


Assuntos
Envelhecimento/fisiologia , Apoptose/fisiologia , Giro Denteado/metabolismo , Hormônio do Crescimento/fisiologia , Melatonina/fisiologia , Animais , Sequência de Bases , Primers do DNA , Hormônio do Crescimento/metabolismo , Masculino , Melatonina/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
8.
Biogerontology ; 14(4): 383-94, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23666345

RESUMO

Changes in the endocrine system have been suggested to act as signaling factors in the regulation of age-related events. Among the different hormones that have been linked to the aging process, estrogens have been widely investigated. They have been associated with inflammatory and oxidative processes and several investigations have established a relationship between the protective effects of estrogens and the mitochondrial function. Mitochondrial DNA is subjected to continuous oxidative attack by free radicals, and the base excision repair (BER) pathway is the main DNA repair route present in mitochondria. We have investigated the effect of estrogen levels on some of the key enzymes of BER in brain and liver mitochondria. In both tissues, depletion of estrogens led to an increased mitochondrial AP endonuclease (mtAPE1) activity, while restoration of estrogen levels by exogenous supplementation resulted in restitution of control APE1 activity only in liver. Moreover, in hepatic mitochondria, changes in estrogen levels affected the processing of oxidative lesions but not deaminations. Our results suggest that changes in mtAPE1 activity are related to specific translocation of the enzyme from the cytosol into the mitochondria probably due to oxidative stress changes as a consequence of changes in estrogen levels.


Assuntos
Encéfalo/fisiologia , Reparo do DNA/fisiologia , Estrogênios/fisiologia , Mitocôndrias Hepáticas/fisiologia , Mitocôndrias/fisiologia , Animais , Feminino , Ratos , Ratos Wistar
9.
J Clin Endocrinol Metab ; 97(8): 2898-906, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22679065

RESUMO

BACKGROUND: Adverse effects of higher endogenous estradiol (E2) levels on various clinical outcomes and on determinants of the frailty syndrome have recently been reported. However, there are no data about the potential relationship between E2 and frailty. We aimed to study the association between E2 levels and frailty among older postmenopausal women not taking hormonal therapy. METHODS: We used data from the Toledo Study for Healthy Aging, a Spanish population-based cohort study. Frailty was defined according to Fried's approach. Multivariate odds ratios (OR) and 95% confidence intervals (CI) associated with E2 levels were estimated using polytomous logistic regression. RESULTS: E2 levels decreased significantly with age and educational level, whereas they increased with body mass index, high-sensitivity C-reactive protein (hs-CRP), and impairment in Katz activities of daily living. Higher E2 levels were associated with the prevalence of frailty among women younger than 79 yr, but not in the oldest group (p interaction = 0.047). After adjustment, OR of frailty associated with a 1 sd increase of E2 was 1.51 (95% CI, 1.04-2.20; P = 0.03). We identified an interaction between E2 and hs-CRP on the prevalence of frailty (P value = 0.042). Women with both higher E2 and hs-CRP (defined as values into the upper tertile) had an age-adjusted OR of 4.2 (95% CI, 1.7-10.5; P = 0.002), compared with women with low levels of both E2 and hs-CRP. CONCLUSION: Higher E2 levels were associated with frailty in postmenopausal women. The synergism between higher E2 and hs-CRP levels suggests the existence of physiopathological mechanisms connecting inflammation and estrogen to frailty.


Assuntos
Estradiol/sangue , Idoso Fragilizado , Pós-Menopausa/sangue , Idoso , Proteína C-Reativa/análise , Estudos de Coortes , Feminino , Humanos
10.
J Physiol Biochem ; 68(2): 255-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22167661

RESUMO

Aging is associated to oxidative damage and alterations in inflammatory and apoptotic pathways. Aging impairs secretion of several hormones, including melatonin and estrogens. However, the mechanisms involved in aging of smooth muscle are poorly known. We have studied the changes induced by aging in the colonic smooth muscle layer of female rats and the protective effect of hormonal therapy. We used young, aged, and ovariectomized aged female rats. Two groups of ovariectomized rats (22 months old) were treated either with melatonin or with estrogen for 10 weeks before sacrifice. Aging induced oxidative imbalance, evidenced by H(2)O(2) accumulation, lipid peroxidation, and decreased catalase activity. The oxidative damage was enhanced by ovariectomy. In addition, aged colonic muscle showed enhanced expression of the pro-inflammatory enzyme cyclooxygenase 2. Expression of the activated forms of caspases 3 and 9 was also enhanced in aged colon. Melatonin and estrogen treatment prevented the oxidative damage and the activation of caspases. In conclusion, aging of colonic smooth muscle induces oxidative imbalance and activation of apoptotic and pro-inflammatory pathways. Hormonal therapy has beneficial effects on the oxidative and apoptotic changes associated to aging in this model.


Assuntos
Envelhecimento/efeitos dos fármacos , Colo/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Melatonina/uso terapêutico , Músculo Liso/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Catalase/metabolismo , Colo/crescimento & desenvolvimento , Colo/metabolismo , Ciclo-Oxigenase 2/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacologia , Estradiol/uso terapêutico , Estrogênios Conjugados (USP)/farmacologia , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Melatonina/farmacologia , Músculo Liso/crescimento & desenvolvimento , Músculo Liso/metabolismo , Ovariectomia , Ratos , Ratos Wistar
11.
J Gerontol A Biol Sci Med Sci ; 66(8): 823-34, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21665987

RESUMO

The effect of a chronic combined treatment with growth hormone (GH) plus melatonin (Mel) on different age-related processes in cytosolic and nuclear fractions of hearts from SAMP8 mice (2 and 10 months) has been investigated. The parameters studied have been messenger RNA expressions of IL-1, IL-10, NFkBp50, NFkBp52, TNFα, eNOS, iNOS, HO-1, HO-2, BAD, BAX, and Bcl2 and protein expressions of iNOS, eNOS, TNFα, IL-1, IL-10, NFkBp50, NFKbp52, and caspase activity (3 and 9). Our results supported the existence of a proapoptotic and oxidative status together with inflammatory processes in the heart of old mice, with increases of inflammatory cytokines, caspase activity, HO-1, BAX, NFkBp50, and NFkBp52 and decreases of eNOS and Bcl2. Also, we were able to observe the translocation of NFkB to nuclei. The combined treatment was able to partially reduce the incidence of these deleterious changes, showing differences with the separated treatments with GH and Mel as were investigated in previous articles from our group.


Assuntos
Envelhecimento/metabolismo , Hormônio do Crescimento Humano/administração & dosagem , Melatonina/administração & dosagem , Miocárdio/metabolismo , Administração Oral , Animais , Apoptose , Biomarcadores/metabolismo , Núcleo Celular/metabolismo , Citosol/metabolismo , Esquema de Medicação , Sinergismo Farmacológico , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/metabolismo , Injeções Subcutâneas , Interleucina-1/genética , Interleucina-1/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Camundongos , Proteínas Musculares/metabolismo , Miocardite/fisiopatologia , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
Anim Reprod Sci ; 126(1-2): 61-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21571454

RESUMO

The aim of the current study was to determine possible differences in ovarian and pituitary features explaining lower fertility rates in sheep with oestrus induced with intravaginal progestagens or prostaglandin analogues (group FGA and PGF, n=8 in both) when compared to a control group (group C, n=8). The growth profiles and the mean individual sizes of preovulatory follicles were similar between groups; however, the number of preovulatory follicles per ewe and, consequently, the number of ovulations were higher in groups FGA and PGF (2.3±0.3 and 2.0±0.1, respectively) than in group C (1.4±0.1, P<0.05). However, plasma oestradiol concentrations were similar between groups suggesting a defective function in some preovulatory follicles of groups FGA and PGF. In group FGA, the basal LH levels during the follicular phase were lower (0.21±0.0 ng/mL, P<0.005) than in groups C (0.41±0.1 ng/mL) and PGF (0.55±0.1 ng/mL); the onset of preovulatory discharge being later (21.0±2.3h vs. 12.8±1.5 in C and 14.5±1.5 in PGF; P<0.05 for both). Finally, luteal activity was also found to be affected in group FGA; the rate of progesterone secretion per total luteal tissue was lower (range: 0.46-0.65 ng/mL/cm(2)) than in ewes treated with cloprostenol (2.1-3.3 ng/mL/cm(2)) and control sheep (2.0-3.4 ng/mL/cm(2)).


Assuntos
Estro/efeitos dos fármacos , Fármacos para a Fertilidade/farmacologia , Ovário/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Progestinas/farmacologia , Ovinos/fisiologia , Animais , Cloprostenol/administração & dosagem , Cloprostenol/farmacologia , Corpo Lúteo/fisiologia , Esquema de Medicação , Feminino , Fase Luteal/efeitos dos fármacos , Fase Luteal/fisiologia , Ovário/fisiologia , Ovulação/efeitos dos fármacos , Ovulação/fisiologia , Hipófise/fisiologia , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia
13.
J Pineal Res ; 49(3): 312-20, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20738757

RESUMO

This study investigated the effect of aging-related parameters such as inflammation, oxidative stress and cell death in the heart in an animal model of accelerated senescence and analyzed the effects of chronic administration of melatonin on these markers. Thirty male mice of senescence-accelerated prone (SAMP8) and 30 senescence-accelerated-resistant mice (SAMR1) at 2 and 10 months of age were used. Animals were divided into eight experimental groups, four from each strain: two young control groups, two old untreated control groups, and four melatonin-treated groups. Melatonin was provided at two different dosages (1 and 10 mg/kg/day) in the drinking water. After 30 days of treatment, the expression of inflammatory mediators (tumor necrosis factor-alpha, interleukin 1 and 10, NFkBp50 and NFkBp52), apoptosis markers (BAD, BAX and Bcl2) and parameters related to oxidative stress (heme oxygenases 1 and 2, endothelial and inducible nitric oxide synthases) were determined in the heart by real-time reverse transcription polymerase chain reaction (RT-PCR). Inflammation, as well as, oxidative stress and apoptosis markers was increased in old SAMP8 males, when compared to its young controls. SAMR1 mice showed significantly lower basal levels of the measured parameters and smaller increases with age or no increases at all. After treatment with melatonin, these age-altered parameters were partially reversed, especially in SAMP8 mice. The results suggest that oxidative stress and inflammation increase with aging and that chronic treatment with melatonin, a potent antioxidant, reduces these parameters. The effects were more marked in the SAMP8 animals.


Assuntos
Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Antioxidantes/farmacologia , Coração/efeitos dos fármacos , Melatonina/farmacologia , Envelhecimento/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Modelos Animais de Doenças , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1/genética , Interleucina-1/genética , Masculino , Camundongos , Subunidade p50 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/genética , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo III/genética , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética
14.
Homo ; 61(4): 277-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20630526

RESUMO

Growth and body height have always been topics interesting to the public. In particular, the stupendous increase of some 15-19cm in final adult height during the last 150 years in most European countries (the "secular trend"), the concomitant changes in body and head proportions, the tendency towards early onset of sexual maturation, the changes in the age when final height is being reached, and the very recent trend in body mass index, have generated much scientific literature. The marked plasticity of growth in height and weight over time causes problems. Child growth references differ between nations, they tend to quickly become out of date, and raise a number of questions regarding fitting methods, effects caused by selective drop-out, etc. New findings contradict common beliefs about the primary importance of nutritional and health related factors for secular changes in growth. There appears to be a broad age span from mid-childhood to early adolescence that is characterised by a peculiar insusceptibility. Environmental factors that are known to influence growth during this age span appear to have only little or no impact on final height. Major re-arrangements in height occur at an age when puberty has almost been completed and final height has almost been reached, implying that factors, which drive the secular trend in height, are limited to early childhood and late adolescence.


Assuntos
Estatura/fisiologia , Desenvolvimento Infantil/fisiologia , Meio Ambiente , Crescimento/fisiologia , Adolescente , Envelhecimento/fisiologia , Criança , Fenômenos Fisiológicos da Nutrição Infantil/fisiologia , Pré-Escolar , Feminino , Alemanha , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores Socioeconômicos , Adulto Jovem
15.
Biogerontology ; 11(3): 275-86, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19731067

RESUMO

The purpose of this study was to investigate the effect of aging on different parameters related to inflammation, oxidative stress and apoptosis in hearts from two types of male mice models: senescence-accelerated mice (SAM-P8) and senescence-accelerated-resistant (SAM-R1), and the influence of chronic administration of Growth Hormone (GH) on old SAM-P8 mice. Forty male mice were used. Animals were divided into five experimental groups: two 10 month old untreated groups (SAM-P8/SAM-R1), two 2 month old young groups (SAM-P8/SAM-R1) and one 10 month old group (SAM-P8) treated with GH for 30 days. The expression of tumor necrosis factor-alpha, interleukin 1, interleukin 10, heme oxygenases 1 and 2, endothelial and inducible nitric oxide synthases, NFkB, Bad, Bax and Bcl-2 were determined by real-time reverse transcription polymerase chain reaction (RT-PCR). Results were submitted to a two way ANOVA statistical evaluation using the Statgraphics program. Inflammation, as well as, oxidative stress and apoptosis markers were increased in the heart of old SAM-P8 males, as compared to young controls and this situation was not observed in the old SAM-R1 mice. Exogenous GH administration reverted the effect of aging in the described parameters of old SAM-P8 mice. Our results suggest that inflammation, apoptosis and oxidative stress could play an important role in the observed cardiovascular alterations related to aging of SAM-P8 mice and that GH may play a potential protective effect on the cardiovascular system of these animals.


Assuntos
Envelhecimento/fisiologia , Hormônio do Crescimento/administração & dosagem , Coração/fisiologia , Envelhecimento/metabolismo , Animais , Sequência de Bases , Citocinas/metabolismo , Primers do DNA , Masculino , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Biogerontology ; 11(2): 229-43, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19633997

RESUMO

There is now a large body of evidence suggesting that the decline in ovarian function with menopause is associated with spontaneous increases in pro-inflammatory cytokines. On the other hand, oxidative stress has been implicated in the pathogenesis of several alterations due to menopause, and can arise through the increased production of lipid peroxides (LPO) and/or a deficiency of antioxidant defense. The aim of the present study was to investigate the effect of aging and ovariectomy on various physiological parameters related to inflammation and oxidative stress in livers obtained from old female rats and the influence of chronic exogenous administration of estrogens, phytoestrogens and growth hormone on these. Thirty-six female Wistar rats of 22 months of age were used in the present study. Twelve of them remained intact, and the other 24 had been ovariectomized at 12 months of age. Intact animals were divided into two groups and treated for 10 weeks with GH or saline, and ovariectomized animals were divided into four groups and treated for the same time with GH, estrogens, phytoestrogens or saline. A group of 2 month old intact female rats was used as young control. Protein expression of iNOS, HO-1, IL-6, TNFalpha, and IL-1beta were determined by Western blot analysis. The levels of NO( x ), LPO, TNFalpha, IL-1beta, IL-6 and IL-10 were determined in different fractions of the liver. Levels of LPO in the liver homogenates as well as iNOS protein expression and NO( x ) levels were increased in old rats as compared to young animals; this effect was more evident in ovariectomized animals. Pro-inflammatory cytokines TNF-alpha, IL-1beta and IL-6 were significantly increased and anti-inflammatory IL-10 decreased during ageing and after ovariectomy. Aging also significantly increased expression of HO-1 protein and ovariectomized rats showed an additional increase. Hormonal administration to the ovariectomized groups decreased NO( x ), LPO levels and pro-inflammatory cytokines as compared with untreated rats. Significant rise in IL-10 and reductions in the iNOS, IL-6, TNFalpha and IL-1beta proteins expression were also found. Oxidative stress and inflammation induced during aging in the liver are more marked in castrated than in intact old females. Administration of the different hormonal replacement therapies was able to inhibit the induction of pro-inflammatory cytokines and iNOS, decreased the levels of oxidative stress markers and had therapeutic potential in the prevention of liver injury.


Assuntos
Envelhecimento/metabolismo , Citocinas/metabolismo , Estrogênios/farmacologia , Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Ovariectomia , Animais , Feminino , Hormônio do Crescimento/farmacologia , Heme Oxigenase-1/metabolismo , Peróxidos Lipídicos/metabolismo , Modelos Animais , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoestrógenos/farmacologia , Ratos , Ratos Wistar
17.
J Reprod Immunol ; 80(1-2): 70-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19410298

RESUMO

Ageing is accompanied by an impairment of the physiological activity of the nervous, endocrine and immune system, as well as in neuroendocrine-immune communication. However, age-related changes in this communication axis have been scarcely studied. In mammals, the process of ageing is associated with an important decline in the secretion of several hormones, such as growth hormone (GH), melatonin (MEL) and oestrogens (Os). Ovariectomy, a model of menopause in rats, has been found to lead to premature immunosenescence. In the present study, the effect of ovariectomy and the role of replacement therapies with GH, MEL, O and natural phyto-oestrogens (POs) have been assessed on several functions in leucocytes from the spleen and the axillary nodes of intact and ovariectomised rats. Chemotaxis, lymphoproliferative response to the mitogen concanavalin A (Con A), the release of interleukin-2 (IL-2) and the natural killer (NK) cell activity have been investigated. Age-controlled rats were used to compare immune functions in hormone treated aged rats with those in younger untreated animals. In all experimental groups, the immune impairment caused by ageing and ovariectomy was partially or completely reversed by hormone treatments. Since the immune system is a marker of health and a predictor of longevity, the results suggest that treatment with hormones could slow down the effects of the ageing process.


Assuntos
Hormônio do Crescimento/administração & dosagem , Melatonina/administração & dosagem , Menopausa/imunologia , Fitoestrógenos/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Fatores Etários , Envelhecimento , Animais , Proliferação de Células , Quimiotaxia/efeitos dos fármacos , Quimiotaxia/imunologia , Concanavalina A/imunologia , Concanavalina A/metabolismo , Citotoxicidade Imunológica , Feminino , Humanos , Interleucina-2/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Menopausa/efeitos dos fármacos , Menopausa/metabolismo , Ovariectomia , Ratos , Ratos Wistar
18.
Theriogenology ; 71(4): 676-82, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19004485

RESUMO

Although various progestagens are often used to induce and synchronize estrus and ovulation in ruminants, concerns regarding residues are the impetus to develop alternative approaches, including reduced doses of progestagens. Therefore, the objective was to determine whether ovarian function was affected by halving the dose of fluorogestone acetate in intravaginal sponges for synchronizing ovulation in sheep during the physiologic breeding season. Twenty Manchega ewes, 4-6-year-old, were randomly allocated to receive an intravaginal sponge containing either 20mg (P20, n=10) or 40 mg of fluorogestone acetate (P40, n=10). Cloprostenol (125 microg) was given at sponge insertion, and all sponges were removed after 6d. Ovarian follicular dynamics (monitored by daily ultrasonography) and other aspects of ovarian function did not differ significantly between the two groups. Ovulatory follicles (OF) grew at a similar growth rate (r=0.62; P<0.001), with comparable initial and maximum diameters (4.2+/-0.4 to 6.0+/-0.3mm in P20 vs. 4.6+/-0.6 to 5.7+/-0.2 mm in P40, mean+/-S.E.M.). Plasma estradiol concentrations (determined once daily) increased linearly during the 72 h interval after sponge removal (1.3+/-0.1 to 3.3+/-0.1 pg/mL for P20, P<0.005 and 1.4+/-0.1 to 3.1+/-0.2 pg/mL for P40, P<0.005). Ten days after sponge removal, ovulation rates (1.2+/-0.2 for P20 and 1.4+/-0.3 for P40), and plasma progesterone concentrations (3.8+/-0.35 ng/mL for P20 and 3.9+/-0.38 ng/mL for P40) were similar. In conclusion, reducing the dose of fluorogestone acetate from 40 to 20mg did not affect significantly ovarian follicular dynamics or other aspects of ovarian function.


Assuntos
Estradiol/sangue , Acetato de Fluorogestona/administração & dosagem , Acetato de Fluorogestona/farmacologia , Folículo Ovariano/fisiologia , Progesterona/sangue , Ovinos , Administração Intravaginal , Animais , Relação Dose-Resposta a Droga , Sincronização do Estro/métodos , Feminino
19.
Georgian Med News ; (159): 34-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18633149

RESUMO

Overweight and obesity have developed into major illnesses in most Western societies and significantly contribute to the financial burden of modern public health systems. Almost daily, new therapeutic proposals are published in the lay press, and also the scientific literature has increased dramatically in recent years. E.g., when searching MEDLINE (1966 - May 2008 (1)), the key word "obesity" meanwhile appears in more than 108,000 articles. Primary focus however, is put upon aspects of treatment, neglecting the role of taste and appetite regulation. Combining keywords like "obesity + treatment" results in over 50.000 citations, "obesity + diet" in over 23.000, "obesity + energy + expenditure" in over 13.000 citations (even "obesity + gastric + bypass" still evoke 2.600 citations), whereas "obesity + appetite + regulation" result in some 3.000, "obesity + NPY" - neuropeptid Y being one of the major chemical stimulators of appetite - evoke some 500 and "obesity + Arc + nucleus" - the arcuate nucleus being the anatomical centre of appetite regulation - no more than 370 scientific publications. The apparent scarcity of literature about taste and appetite regulation and the amazing lack of interest in neuronal information processing in overweight and obesity, has prompted the authors to brainstorm new aspects of the world-wide derailment of weight control.


Assuntos
Apetite/fisiologia , Congressos como Assunto , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Paladar/fisiologia , Humanos , Obesidade/reabilitação , Sobrepeso/reabilitação
20.
Reprod Domest Anim ; 43(1): 9-14, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18199252

RESUMO

The study reports on differences in the dynamics of growth and functionality of preovulatory follicles in response to oestrous synchronization, either by the administration of two doses of prostaglandin or by an intravaginal progestagen sponge, in goats. The progestagen-treated group (n = 8) showed more follicles of preovulatory size (> or =5.5 mm) than the cloprostenol group (n = 8) during the follicular phase (4.5 +/- 0.6 vs 1.9 +/- 0.2, p < 0.01). The diameters of the largest follicles (LF1, LF2 and LF3) were also larger in the progestagen group (LF1, 7.8 +/- 0.3 vs 7.0 +/- 0.2 mm, p < 0.05; LF2, 6.7 +/- 0.2 vs 5.6 +/- 0.2 mm, p < 0.01; LF3, 5.5 +/- 0.3 vs 4.2 +/- 0.2 mm, p < 0.01). The study of the preovulatory follicles showed that 27.2% (3/11) of the follicles were in the static phase in the cloprostenol group, whilst 71.4% (10/14) were static in progestagen group (p < 0.05). Higher plasma oestradiol levels were recorded in the progestagen-treated goats during the 48 h prior to cloprostenol injection or progestagen withdrawal (4.2 +/- 0.4 vs 3.0 +/- 0.2 pg/ml, p < 0.05). In conclusion, goats with oestrus synchronized by progestagen showed a higher number of preovulatory-sized follicles, but a decreased oestradiol secretion when compared with does with oestrus synchronized by using prostaglandin analogues. These would support the development of alternative protocols for assisted reproduction.


Assuntos
Sincronização do Estro , Cabras/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Progestinas/farmacologia , Prostaglandinas Sintéticas/farmacologia , Administração Intravaginal , Animais , Cloprostenol/administração & dosagem , Estradiol/metabolismo , Sincronização do Estro/efeitos dos fármacos , Sincronização do Estro/métodos , Feminino , Injeções Intramusculares/veterinária , Luteolíticos/administração & dosagem , Distribuição Aleatória
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