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1.
J Invertebr Pathol ; 196: 107870, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36493843

RESUMO

Larvae of the invasive pest Drosophila suzukii are susceptible to the Steinernema carpocapsae - Xenorhabdus nematophila complex and an assessment of the immune-regulatory system activation in this insect was performed to understand the response to the nematode infection. The expressions of 14 immune-related genes of different pathways (Imd, Toll, Jak-STAT, ProPO, JNK, TGF-ß) were analyzed using qRT-PCR to determine variations after nematode penetration (90 min and 4 h) and after bacterial release (14 h). Before the bacteria were present, the nematodes were not recognized by the immune system of the larvae and practically none of the analyzed pathways presented variations when compared with the non-infected larvae. However, after the X. nematophila were released, PGRP-LC was activated leading to the gene upregulation of antimicrobial peptides of both the Toll and Imd pathways. Interestingly, the cellular response was inactive during the infection course as Jak/STAT and pro-phenoloxidase genes remained unresponsive to the presence of both pathogens. These results illustrate how D. suzukii immune pathways responded differently to the nematode and bacteria along the infection course.


Assuntos
Rabditídios , Xenorhabdus , Animais , Drosophila , Larva/microbiologia , Xenorhabdus/genética , Simbiose , Rabditídios/genética
2.
Drug Metab Dispos ; 50(4): 327-340, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35042701

RESUMO

Lurbinectedin is a novel and potent selective inhibitor of active transcription of protein-coding genes, triggering apoptosis of cancerous cells. It has been approved for the treatment of patients with metastatic small-cell lung cancer with disease progression on or after platinum-based chemotherapy. Studies exploring the disposition and metabolism of lurbinectedin were performed in vitro and in vivo (by intravenous administration of lurbinectedin). Low blood cell partitioning for lurbinectedin in rats, nonhuman primates (NHP), and humans was determined as 23.4%, 29.8%, and 9.8%, respectively. Protein binding was very high (>95%) in total plasma (rat, NHP, and human), albumin, and α-1-acid glycoprotein (both human). In vitro, lurbinectedin underwent intense liver microsome-mediated metabolism-in 10 minutes, 80% of the compound is metabolized in human-with CYP3A4 being the isoform involved in that metabolism. Results also showed NHPs being the nonclinical species which, metabolically, most closely resembles humans. Mass balance studies performed in rats (both genders), NHPs (male only), and patients (both genders) demonstrated that the principal route of excretion of 14C-lurbinectedin-related radioactivity was through the feces (88.7% ± 10.1% in patients), with only a minor fraction recovered from the urine (5.6% ± 2.0% in patients). In plasma samples, the majority of lurbinectedin-related radioactivity was attributed to unchanged compound (95% ± 3.1% and 70.2% ± 10.9% in NHPs and humans, respectively). Plasma metabolic profiling demonstrated the major (% compared with unchanged compound) circulating metabolites were N-Desmethyl-lurbinectedin (0.4% ± 0.2% and 10.4% ± 2.2% in NHPs and patients, respectively) and 1',3'-Desmethylene-lurbinectedin (0.9% ± 0.7% and 14.3% ± 10.4% in NHP and patients, respectively). SIGNIFICANCE STATEMENT: Lurbinectedin is a novel and potent selective inhibitor of active transcription of protein-coding genes, triggering apoptosis of cancerous cells, and was recently approved for the treatment of patients with metastatic small-cell lung cancer with disease progression on or after platinum-based chemotherapy. The present study provides a complete set of information on the pharmacokinetics, biotransformation, and elimination of 14C-lurbinectedin and its metabolites, following a single intravenous administration to nonclinical species (rats and nonhuman primates) and patients.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Carbolinas/farmacologia , Carbolinas/uso terapêutico , Fezes , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Ratos , Carcinoma de Pequenas Células do Pulmão/induzido quimicamente , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia
3.
J Dairy Sci ; 104(11): 11580-11592, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454748

RESUMO

The continuous trend for a narrowing margin between feed cost and milk prices across dairy farms in the United States highlights the need to improve and maintain feed efficiency. Yeast culture products are alternative supplements that have been evaluated in terms of milk performance and feed efficiency; however, less is known about their potential effects on altering rumen microbial populations and consequently rumen fermentation. Therefore, the objective of this study was to evaluate the effect of yeast culture supplementation on lactation performance, rumen fermentation profile, and abundance of major species of ruminal bacteria in lactating dairy cows. Forty mid-lactation Holstein dairy cows (121 ± 43 days in milk; mean ± standard deviation; 32 multiparous and 8 primiparous) were used in a randomized complete block design with a 7-d adaptation period followed by a 60-d treatment period. Cows were blocked by parity, days in milk, and previous lactation milk yield and assigned to a basal total mixed ration (TMR; 1.6 Mcal/kg of dry matter, 14.6% crude protein, 21.5% starch, and 38.4% neutral detergent fiber) plus 114 g/d of ground corn (CON; n = 20) or basal TMR plus 100 g/d of ground corn and 14 g/d of yeast culture (YC; n = 20; Culture Classic HD, Cellerate Yeast Solutions, Phibro Animal Health Corp.). Treatments were top-dressed over the TMR once a day. Cows were individually fed 1 × /d throughout the trial. Blood and rumen fluid samples were collected in a subset of cows (n = 10/treatment) at 0, 30, and 60 d of the treatment period. Rumen fluid sampled via esophageal tubing was analyzed for ammonia-N, volatile fatty acids (VFA), and ruminal bacteria populations via quantitative PCR amplification of 16S ribosomal DNA genes. Milk yield was not affected by treatment effects. Energy balance was lower in YC cows than CON, which was partially explain by the trend for lower dry matter intake as % body weight in YC cows than CON. Cows fed YC had greater overall ruminal pH and greater total VFA (mM) at 60 d of treatment period. There was a contrasting greater molar proportion of isovalerate and lower acetate proportion in YC-fed cows compared with CON cows. Although the ruminal abundance of specific fiber-digesting bacteria, including Eubacterium ruminantium and Ruminococcus flavefaciens, was increased in YC cows, others such as Fibrobacter succinogenes were decreased. The abundance of amylolytic bacteria such as Ruminobacter amylophilus and Succinimonas amylolytica were decreased in YC cows than CON. Our results indicate that the yeast culture supplementation seems to promote some specific fiber-digesting bacteria while decreasing amylolytic bacteria, which might have partially promoted more neutral rumen pH, greater total VFA, and isovalerate.


Assuntos
Lactação , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Digestão , Eubacterium , Feminino , Fermentação , Fibrobacter , Leite , Gravidez , Rúmen/metabolismo , Ruminococcus , Saccharomyces cerevisiae , Succinivibrionaceae
4.
J Dairy Sci ; 102(1): 547-556, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30527989

RESUMO

This study was designed to evaluate the response of hematological and biochemical parameters submitted to pegbovigrastim administration and postchallenge with lipopolysaccharide (LPS). In experiment 1, 20 newborn Holstein calves were divided into 2 groups: the Imrestor (Elanco Saúde Animal, São Paulo, Brazil) group (IMR, n = 10), which received a 25 µg/kg of body weight (BW) subcutaneous administration of pegbovigrastim, and the control group (CTR, n = 10), which received a subcutaneous administration of 0.9% saline solution. Blood samples were collected on d 0, 10, 12, and 14 relative to birth to analyze the biochemical and hematological parameters. Moreover, growth measurements were taken on d 0, 7, 14, 21, and 60 relative to birth. The number of total leukocytes in the IMR group increased on d 12 and 14 in comparison to the CTR group, as well as the counts of segmented neutrophils, band cells, and monocytes. No differences were observed in the other hematological, biochemical, and growth parameters. In experiment 2, 20 Holstein calves from 30 to 60 d old were divided into 4 groups: group 1 (LPS, n = 5) received a 0.25 µg/kg of BW single intravenous dose of Escherichia coli LPS at d 0; group 2 (IMR, n = 5) received a 25 µg/kg of BW subcutaneous dose of pegbovigrastim at d 1; group 3 (IMR + LPS, n = 5) received a 0.25 µg/kg of BW intravenous LPS dose at d 0 and a 25 µg/kg of BW subcutaneous dose of pegbovigrastim at d 1; and group 4 (CTR, n = 5) received an intravenous dose of 0.9% sodium chloride at d 0 and a subcutaneous dose of 0.9% sodium chloride at d 1. For the analysis of biochemical and hematological parameters, blood samples were collected on d -1, 0, 1, 2, 3, 4, 8, 14, and 21 relative to LPS administration. An increase in the number of total leukocytes was observed in the IMR, IMR + LPS, and LPS groups, and the IMR group remained as the highest from d 2 to 21. The levels of paraoxonase 1 were higher in the IMR group compared with all the others. The administration of pegbovigrastim in the dairy calves increased the number of circulating leukocytes, especially neutrophils, with an increase in paraoxonase 1, without altering the metabolites for the hepatic function.


Assuntos
Anti-Inflamatórios/administração & dosagem , Bovinos/sangue , Fenilalanina/administração & dosagem , Administração Cutânea , Animais , Peso Corporal/efeitos dos fármacos , Brasil , Bovinos/crescimento & desenvolvimento , Feminino , Contagem de Leucócitos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Fenilalanina/análogos & derivados , Gravidez
5.
J Dairy Sci ; 100(1): 213-223, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28341042

RESUMO

Sorghum silage has been shown to be a good alternative to corn silage for dairy cows; however, studies regarding heifers are insufficiently explored. Therefore, the objective of this study was to evaluate effects of changing forage to concentrate ratio (FOR:CON) in diets based on sorghum silage on N digestibility, rumen fermentation, N balance, C excretion, and microbial N yield in limit-fed dairy heifers. A split-plot 4×4 Latin square design with 19-d periods (15 d of adaptation and 4 d of sampling) was conducted with 8 rumen cannulated dairy heifers (age 13.7±0.6mo and weight 364.8±17.6kg). Heifers were fed sorghum silage-based diets with 4 FOR:CON (85:15, 75:25, 65:35, and 55:45) balanced for similar metabolizable energy intake per unit of body weight and crude protein concentration. Diets were fed to allow 900 to 1,000g/d body weight gain and were fed once daily. Total collection of feces and urine was completed on d 15 to 19 to determine N, C, urea N, allantoin, uric acid, and creatinine excretion. Rumen contents were sampled on d 19 at 0, 1.5, 3, 4.5, 6, 9, 13, 17, 21, and 23h after feeding to measure pH, volatile fatty acid (VFA), ammonia-N, and free AA concentrations. The pH decreased linearly while ammonia-N and free AA levels increased linearly with decreasing FOR:CON of diets. Although mean total VFA did not differ among treatment diets, molar proportions of VFA did. Acetate proportion decreased while propionate and butyrate increased with decreasing FOR:CON. Intake of N and urea N excretion decreased with decreasing forage proportion in diets while total N excretion, apparent N digestibility, and N retention were not different. Intake of C and excretion in feces (g/d) decreased linearly with decreasing FOR:CON in diets. Creatinine, allantoin, and uric acid excretion were not affected by FOR:CON; however, microbial N yield tended to increase linearly with greater concentrate in diets. Heifers limit fed diets based on sorghum silage demonstrated the effect of available ammonia-N and readily fermentable carbohydrates with subsequent effects on nutrient utilization when different FOR:CON were applied. Based on the presented results, FOR:CON 65:35 had the most suitable balance of available ammonia-N and readily fermentable carbohydrates for the most optimal results.


Assuntos
Rúmen/metabolismo , Silagem , Animais , Bovinos , Dieta/veterinária , Digestão , Feminino , Fermentação , Lactação , Purinas , Sorghum , Zea mays
6.
J Dairy Sci ; 100(1): 224-235, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28341043

RESUMO

Sorghum forage is an alternative crop that is more adapted to drier conditions and more resistant than corn to drought conditions. Thus, sorghum forage maximizes water utilization. The objective of this study was to evaluate sorghum silage (SS), including digestibility and fermentation parameters, in precision-fed dairy heifers. Eight Holstein heifers (13.7±0.6mo of age and 364.8±17.64kg of body weight) fitted with rumen cannulas were used in a replicated 4×4 Latin Square design; treatments were 4 levels of forage to concentrate ratios (85:15, 75:25, 65:35, and 55:45). Rumen contents were sampled at various times to determine pH and volatile fatty acid concentrations. Dry matter (DM) and neutral detergent fiber (NDF) in situ degradation kinetics were compared between SS and corn silage (CS) diets. Fecal total collection was used to estimate apparent total-tract digestibility. Fecal grab samples at 0, 6, 12, and 18h after feeding were used to estimate total-tract starch digestibility. Amount of concentrate in the diet affected the time that heifers spent eating as well as rumen pH. When the concentrate proportion of the diet increased, eating time and rumen pH decreased linearly. Total volatile fatty acid concentrations were not affected by treatment, but butyrate increased as the proportion of concentrate increased in the diet. Digestibility of DM and starch were higher in diets with lower forage to concentrate ratio, but NDF, acid detergent fiber, and hemicellulose digestibility were not affected. Corn silage had greater DM and NDF digestibility than SS. Also, fractional rate of digestion was faster for CS than SS (2.78 vs. 2.42% per hour, respectively). We conclude that fecal grab samples are suitable for predicting starch digestibility in heifers given the starch levels studied. In addition, SS was an adequate alternative forage in precision-fed dairy heifers with outcomes very similar to CS-based rations.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Sorghum , Animais , Bovinos , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Feminino , Lactação , Rúmen/metabolismo , Silagem , Zea mays/metabolismo
7.
J Dairy Sci ; 99(4): 2797-2810, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26851846

RESUMO

The objective of this study was to evaluate the effect of different forms of trace minerals (TM) and the use of different starch levels in dairy heifer diets on rumen fermentation and digestibility. Eight rumen cannulated dairy heifers (15.4 ± 0.8 mo of age and 438.31 ± 18.08 kg of body weight) were subjected to a split-plot, 4 × 4 Latin square design with 19-d periods: 15d of adaptation and 4d of sampling. The whole-plot factor was type of TM; organic as proteinates (OTM) or inorganic sulfates (ITM), and the subplot was starch level (3.54, 12.95, 22.25, and 31.73%). Total collection of feces and urine was completed on d 15 to 19 to determine digestibility and TM excretion. Rumen contents were sampled on d 18 to 19 at 0, 1, 2, 4, 8, 12, 16, 20, and 22 h after feeding to measure pH and volatile fatty acid (VFA) concentrations. Plasma samples were collected to evaluate TM concentrations and enzymatic activity for ceruloplasmin, glutathione peroxidase, and superoxide dismutase. Starch level affected pH, individual VFA concentrations, and nutrient excretion. Trace mineral intake was lower for OTM compared with ITM. No effect of TM form on dry matter digestibility was detected, but as level of starch increased, diet dry matter digestibility increased. Rumen pH was lower for diets with OTM, which is consistent with higher total VFA production and butyrate proportion observed for heifers fed OTM diets. These variables may be explained by the higher bioavailability of OTM and faster utilization and fermentation by rumen microorganisms. Heifers that consumed ITM had higher moisture in feces and higher urine excretion, which increased total manure production. Total excretion of TM was not different by treatment. Blood plasma mineral concentration was not different between treatments except for Mn, which was higher for OTM. Enzymatic activity was not affected by treatments. Mineral intake was reduced and blood mineral levels were not different, suggesting enhanced absorption of OTM compared with ITM. In conclusion, based on rumen pH, VFA production, and plasma TM concentration, OTM may be more ruminally bioavailable and absorbed to a greater extent than ITM. Also, TM form affected fecal moisture and urine excretion, suggesting that ITM may stimulate water intake.


Assuntos
Bovinos/metabolismo , Dieta/veterinária , Fermentação , Minerais/metabolismo , Rúmen/metabolismo , Amido/metabolismo , Oligoelementos/metabolismo , Ração Animal/análise , Animais , Indústria de Laticínios , Ácidos Graxos Voláteis/análise , Fezes/química , Feminino , Conteúdo Gastrointestinal/química , Concentração de Íons de Hidrogênio , Minerais/sangue
8.
Mol Cell Biochem ; 390(1-2): 235-42, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24573886

RESUMO

Breast cancer is one of the common tumors occurring in woman and despite treatment, the prognostic is poor. Genistein, a soy isoflavone, has been reported to have chemopreventive\chemotherapeutic potential in multiple tumor types. Here, we investigated the genistein antiproliferative effect in MCF-7 breast cancer, underlying the molecular mechanisms involved in this effect. MCF-7 cancer and CCD1059sK fibroblast cells were treated with estradiol (10 nM) or genistein (0.01-100 µM) for 24, 48, and 72 h and the cell proliferation was investigated by MTT; membrane cell permeability was evaluated by LDH and PI incorporation; apoptosis was investigated by externalization of phosphatidylserine by FACS; and presence of autophagy was detected by LC3A/B immunostaining. The expression of apoptotic proteins and antioxidant enzymes was evaluated by qPCR. The results demonstrate that genistein (100 µM) for 72 h of treatment selectively reduced MCF-7 cell proliferation independent of estrogen receptor activation, while no cytotoxicity was observed in fibroblast cells. Further experiments showed that genistein induced phosphatidylserine externalization and LC3A/B immunopositivity in MCF-7 cells, indicating apoptosis and autophagy cell death. Genistein increased in three times proapoptotic BAX/Bcl-2 ratio and promoted a parallel downregulation of 20 times of antiapoptotic survivin. In addition, genistein promoted a decrease of 5.5, 9.3, and 3.6 times of MnSOD, CuZnSOD, and TrxR mRNA expression, respectively, while the GPx expression was increased by 6.5 times. These results suggest that the antitumor effect of genistein involved the modulation of antioxidant enzyme and apoptotic signaling expression, which resulted in apoptosis and progression of autophagy.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias da Mama/genética , Genisteína/administração & dosagem , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Estresse Oxidativo/genética , Proteína X Associada a bcl-2/metabolismo
9.
Br Poult Sci ; 54(6): 780-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24397514

RESUMO

1. This study evaluated the effects of diets with partial and total substitution of soya bean oil (SO) with flaxseed (linseed) oil (FO) on broiler chicken performance, carcass traits, meat chemical composition and blood serum metabolites. 2. A total of 448 one-d-old Cobb 500 broiler chicken were used. They were allotted among 4 treatments with 8 replications, using a completely randomised design, for 35 d. Four diets were compared: T1 = 100% SO (3%, 1-7 d; 4%, 8-21 d; and 5%, 22-35 d); T2 = 50% SO + 50% FO; T3 = 25% SO + 75% FO and T4 = 100% FO. 3. No significant differences were observed in body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and blood serum metabolites (total triglycerides, TRI; total cholesterol, CHO; high-density lipoprotein, HDL; low-density lipoprotein, LDL; glucose, GLU; albumin, ALB; globulin, GLO; and total proteins, TPs). Significant effects were observed for TRI, CHO, HDL, GLU, HDL, LDL, ALB and GLO with regard to the day of collection. 4. Carcass traits did not show significant differences for the treatments. No significant differences were observed for breast and drumstick chemical compositions, with the exception of drumstick fat concentration (quadratic effect). 5. In conclusion, the partial or total substitution of SO with FO did not affect growth performance, carcass traits, meat chemical composition or blood serum profile in broiler chicken. Therefore, FO can be an alternative to SO in the diet formulation for broiler chicken.


Assuntos
Galinhas/fisiologia , Óleo de Semente do Linho/farmacologia , Carne/análise , Aumento de Peso/efeitos dos fármacos , Ração Animal/análise , Animais , Análise Química do Sangue/veterinária , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Relação Dose-Resposta a Droga , Óleo de Semente do Linho/administração & dosagem
10.
Metabolism ; 115: 154460, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33285180

RESUMO

BACKGROUND: Reproduction is tightly coupled to body energy and metabolic status. GnRH neurons, master elements and final output pathway for the brain control of reproduction, directly or indirectly receive and integrate multiple metabolic cues to regulate reproductive function. Yet, the molecular underpinnings of such phenomenon remain largely unfolded. AMP-activated protein kinase (AMPK), the fundamental cellular sensor that becomes activated in conditions of energy deficit, has been recently shown to participate in the control of Kiss1 neurons, essential gatekeepers of the reproductive axis, by driving an inhibitory valence in situations of energy scarcity at puberty. However, the contribution of AMPK signaling specifically in GnRH neurons to the metabolic control of reproduction remains unknown. METHODS: Double immunohistochemistry (IHC) was applied to evaluate expression of active (phosphorylated) AMPK in GnRH neurons and a novel mouse line, named GAMKO, with conditional ablation of the AMPK α1 subunit in GnRH neurons, was generated. GAMKO mice of both sexes were subjected to reproductive characterization, with attention to puberty and gonadotropic responses to kisspeptin and metabolic stress. RESULTS: A vast majority (>95%) of GnRH neurons co-expressed pAMPK. Female (but not male) GAMKO mice displayed earlier puberty onset and exaggerated LH (as surrogate marker of GnRH) responses to kisspeptin-10 at the prepubertal age. In adulthood, GAMKO females retained increased LH responsiveness to kisspeptin and showed partial resilience to the inhibitory effects of conditions of negative energy balance on the gonadotropic axis. The modulatory role of AMPK in GnRH neurons required preserved ovarian function, since the differences in LH pulsatility detected between GAMKO and control mice subjected to fasting were abolished in ovariectomized animals. CONCLUSIONS: Altogether, our data document a sex-biased, physiological role of AMPK signaling in GnRH neurons, as molecular conduit of the inhibitory actions of conditions of energy deficit on the female reproductive axis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/sangue , Neurônios/metabolismo , Reprodução/fisiologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Ciclo Estral/metabolismo , Feminino , Kisspeptinas/farmacologia , Masculino , Desnutrição/metabolismo , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Fosforilação , Caracteres Sexuais , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
11.
Am J Physiol Endocrinol Metab ; 299(1): E54-61, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20407007

RESUMO

Severe inflammatory challenges are frequently coupled to decreased food intake and disruption of reproductive function, the latter via deregulation of different signaling pathways that impinge onto GnRH neurons. Recently, the hypothalamic Kiss1 system, a major gatekeeper of GnRH function, was suggested as potential target for transmitting immune-mediated repression of the gonadotropic axis during acute inflammation, and yet key facets of such a phenomenon remain ill defined. Using lipopolysaccharide S (LPS)-treated male rats as model of inflammation, we document herein the pattern of hypothalamic kisspeptin immunoreactivity (IR) and hormonal responses to kisspeptin during the acute inflammatory phase. LPS injections induced a dramatic but transient drop of serum LH and testosterone levels. Suppression of gonadotropic function was associated with a significant decrease in kisspeptin-IR in the arcuate nucleus (ARC) that was not observed under conditions of metabolic stress induced by 48-h fasting. In addition, absolute responses to kisspeptin-10 (Kp-10), in terms of LH and testosterone secretion, were significantly attenuated in LPS-treated males that also displayed a decrease in food intake and body weight. Yet pair-fed males did not show similar alterations in LH and testosterone secretory responses to Kp-10, whose magnitude was preserved, if not augmented, during food restriction. In summary, our data document the impact of acute inflammation on kisspeptin content at the ARC as key center for the neuroendocrine control of reproduction. Our results also suggest that suppressed gonadotropic function following inflammatory challenges might involve a reduction in absolute responsiveness to kisspeptin that is independent of the anorectic effects of inflammation.


Assuntos
Núcleo Arqueado do Hipotálamo/fisiopatologia , Hipogonadismo/fisiopatologia , Inflamação/fisiopatologia , Hormônio Luteinizante/fisiologia , Oligopeptídeos/fisiologia , Testosterona/fisiologia , Animais , Área Sob a Curva , Ingestão de Alimentos/fisiologia , Imuno-Histoquímica , Kisspeptinas , Hormônio Luteinizante/sangue , Masculino , Ratos , Ratos Wistar , Testosterona/sangue
12.
Am J Physiol Endocrinol Metab ; 299(1): E39-46, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20424142

RESUMO

RF-amide related peptides (RFRP), as putative mammalian orthologs of the avian gonadotropin-inhibitory hormone (GnIH), have been proposed as key regulators of gonadotropin secretion in higher vertebrates. Yet considerable debate has arisen recently on their physiological relevance and potential mechanisms and sites of action. Present studies were undertaken to further characterize the effects of RFRP on LH and FSH secretion by a combination of in vivo and in vitro approaches in male and female rats. Initial screening via intracerebroventricular (icv) administration of different analogs of RFRP1 (RFRP1-12 and RFRP1-20) and RFRP3 (RFRP3-8 and RFRP3-17), as well as the related neuropeptide FF (NPFF8), to gonadectomized (GNX) female rats evidenced significant, albeit modest, inhibitory effects on LH secretion only for RFRP3-8 and RFRP3-17, which were detectable at the high dose rage (1 nmol for RFRP3-8, 5 nmol for RFRP3-17). This moderate inhibitory action was also documented after icv administration of RFRP3-8 to intact and GNX male rats. In addition, systemic (intravenous) administration of RFRP3-8 decreased the circulating levels of both gonadotropins in GNX male rats. Likewise, RFRP3-8 inhibited basal and GnRH-stimulated LH secretion by pituitaries from GNX males in vitro. This inhibitory effect was blocked by the antagonist of RFRP receptors, RF9. In summary, our results support a putative inhibitory role of RFRP3 as ortholog of GnIH in the regulation of gonadotropin secretion in mammals, which appears to involve direct pituitary actions as well as potential central (hypothalamic) effects.


Assuntos
Hormônio Foliculoestimulante/fisiologia , Hormônio Luteinizante/fisiologia , Neuropeptídeos/fisiologia , Hipófise/fisiologia , Animais , Área Sob a Curva , Relação Dose-Resposta a Droga , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Masculino , Hipófise/metabolismo , Ratos , Ratos Wistar
13.
Reprod Domest Anim ; 45(6): 1110-3, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19663813

RESUMO

This study aimed to evaluate the effect of the exogenous recombinant bovine somatotropin (rbST) on plasma concentrations of insulin-like growth factor I (IGF-I), insulin and semen quality of bulls. Twenty bulls (Aberdeen Angus and Brangus) were divided by breed into two groups. Placebo group was injected with NaCl 0.9% (s.c.) and treatment group with rbST (s.c., 500 mg) at days 0 and 14 of the experiment. Immediately after semen collection, blood samples were taken on days 0, 14, 28, 42 and 56 of the experiment. Semen was also collected on day 70 of the experiment. Evaluation of sperm motility was performed at pre-freezing and post-thawing stage, whereas assessment of sperm membrane integrity was performed after freezing and thawing. Analysis of data revealed that the effect of treatment and treatment-by-collection day on plasma concentrations of IGF-I and insulin was not significant. However, mean plasma concentrations of IGF-I and insulin were affected (p < 0.0001) by days of blood sampling. Effect of treatment and treatment-by-collection day on motility of spermatozoa was similar (p > 0.05) at pre-freezing and post-thawing stage. Intactness of plasmalemma and tail membrane of spermatozoa at post-thawing stage was higher (p < 0.05) in rbST-treated group than in control. In conclusion, rbST did not affect plasma concentrations of IGF-I and insulin, however, it did improve post-thaw sperm membrane integrity.


Assuntos
Bovinos/sangue , Hormônio do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Insulina/sangue , Espermatozoides/fisiologia , Animais , Criopreservação , Fator de Crescimento Insulin-Like I/genética , Masculino , Proteínas Recombinantes , Preservação do Sêmen , Espermatozoides/efeitos dos fármacos
14.
Sci Rep ; 10(1): 13898, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807904

RESUMO

In addition to its essential role in the physiological control of longitudinal growth, growth-hormone (GH) is endowed with relevant metabolic functions, including anabolic actions in muscle, lipolysis in adipose-tissue and glycemic modulation. Adult obesity is known to negatively impact GH-axis, thereby promoting a vicious circle that may contribute to the exacerbation of the metabolic complications of overweight. Yet, to what extent early-overnutrition sensitizes the somatotropic-axis to the deleterious effects of obesity remains largely unexplored. Using a rat-model of sequential exposure to obesogenic insults, namely postnatal-overfeeding during lactation and high-fat diet (HFD) after weaning, we evaluated in both sexes the individual and combined impact of these nutritional challenges upon key elements of the somatotropic-axis. While feeding HFD per se had a modest impact on the adult GH-axis, early overnutrition had durable effects on key elements of the somatotropic-system, which were sexually different, with a significant inhibition of pituitary gene expression of GH-releasing hormone-receptor (GHRH-R) and somatostatin receptor-5 (SST5) in males, but an increase in pituitary GHRH-R, SST2, SST5, GH secretagogue-receptor (GHS-R) and ghrelin expression in females. Notably, early-overnutrition sensitized the GH-axis to the deleterious impact of HFD, with a significant suppression of pituitary GH expression in both sexes and lowering of circulating GH levels in females. Yet, despite their similar metabolic perturbations, males and females displayed rather distinct alterations of key somatotropic-regulators/ mediators. Our data document a synergistic effect of postnatal-overnutrition on the detrimental impact of HFD-induced obesity on key elements of the adult GH-axis, which is conducted via mechanisms that are sexually-divergent.


Assuntos
Dieta Hiperlipídica , Hormônio do Crescimento/metabolismo , Obesidade/etiologia , Hipernutrição/complicações , Caracteres Sexuais , Animais , Peso Corporal , Feminino , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Modelos Biológicos , Obesidade/genética , Especificidade de Órgãos , Hipernutrição/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo
15.
J Pharm Biomed Anal ; 169: 70-74, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30831452

RESUMO

A new method for the quantification of metabolites in the absence of a chemically synthetized authentic standard is described herein. Metabolites to be used as reference standards were obtained biologically from microsomes incubation. The method is a stepwise process in which, only the radiolabeled (14C) and non-radiolabeled parent compound are required. Briefly, the separation and principles of equimolar detection of LC-radioactivity were applied and, a calibration curve of the 14C-parent compound was used to quantify the formation of its 14C-metabolite. In turn, serial dilutions of this 14C-metabolite were the base for the calibration curve that allowed the quantification of the non-radiolabeled metabolite. This method was applied in plasma samples obtained from a dog pharmacokinetic study in which, a PharmaMar compound (lurbinectedin) and its N-desmethylated metabolite were quantified and, the results compared to those obtained by the classical approach (with the chemically synthetized N-desmethylated metabolite). Plasma concentrations obtained with the two methods were very similar, with standard relative errors between -11% to -4%. Similar, main pharmacokinetic parameters were calculated with the concentrations obtained either thru this method or by using a chemically synthetized authentic standard.


Assuntos
Análise Química do Sangue/métodos , Animais , Calibragem , Radioisótopos de Carbono/química , Cromatografia Líquida , Cães , Microssomos/química , Microssomos/metabolismo , Plasma/química , Padrões de Referência , Suínos , Porco Miniatura
16.
Sci Rep ; 9(1): 9154, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235878

RESUMO

The possibility to detect fast neutrons as a distinct signal from that one of γ-rays background is surely of great importance for several topics, spanning from homeland security to radiation monitoring in nuclear physics research plants. Nowadays, Helium-3 based detectors are extremely expensive, while the use of large volume liquid scintillators presents serious concerns related to spillage risks and waste disposal. A very attractive alternative is the use of commercially available solid scintillators, which exploits an aromatic polymer matrix entrapping very high loadings of primary dye, thereby enabling the use of pulse shape analysis (PSA) to discriminate between fast neutrons and γ-rays. In this work, we analyse in detail the optical features of a solid scintillator composed by polymethylphenylsiloxane (PMPS) as base polymer loaded with moderate amounts of 2,5-diphenyloxazole (PPO). Furthermore, fluorescence decay kinetics have been correlated to the observed pulse shape discrimination capabilities of this radiation and thermally resistant scintillator, whose performances have been discussed in terms of conformational features and excimers formation revealed by the optical analyses.

17.
Res Vet Sci ; 124: 334-337, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31048181

RESUMO

The aims of the current study were to assess the inclusion levels of grape byproduct replacing jiggs hay in lambs diets and to evaluate signs of copper poisoning. Thirty-four Texel and Corriedale crossbred female lambs were used in a randomized block experimental design. The treatments comprised four levels of grape byproduct (0; 100; 200 and 300 g/kg DM) in replacement of jiggs hay. The diets were adjusted to the same ZnCu ratio (6:1) of the basal diet. Grape byproduct consumption at up to 30%, led to similar weight gain in the different treatments (P = .92), which was suitable for growing lambs. Grape byproduct in the diet had linear effect on GGT (P < .001) and AST (P < .0001) enzymes as well as on total bilirubin (P = .05). In addition, the highest grape byproduct addition showed the highest consumption of hay (P < .01). Hay replacement by grape byproduct at up to 300 g/kg in the DM was satisfactory to weight gain and did not negatively affect feed intake and weight gain of growing lambs. Maintaining zinc:copper ratio in sheep diets is not effective in preventing liver damage caused by increased dietary copper concentrations over a period of 70 days.


Assuntos
Cobre/intoxicação , Intoxicação por Metais Pesados/veterinária , Carneiro Doméstico/fisiologia , Vitis/química , Zinco/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Intoxicação por Metais Pesados/prevenção & controle , Zinco/administração & dosagem
18.
Dev Biol (Basel) ; 131: 167-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18634477

RESUMO

Rabies in dogs was unknown in the Americas before the arrival of the Spanish "Conquistadores". Until the mid-1980s rabies in animals and, in turn in humans, changed little from year to year, with the number of dog vaccinations reported annually rarely reaching one million. In Mexico, the national rabies control programme using mass parenteral vaccination of dogs started in 1990 with about seven million dogs vaccinated the same year. The number of vaccinated dogs exceeded 10 and 15 million in 1995 and 2005, respectively. Modern cell culture-based inactivated rabies virus vaccines were used. A key factor for the success of the dog rabies control program was the supply of potent canine rabies vaccines. Between 1990 and 2005, more than 150 million vaccine doses from 300 lots were administered. Each lot was tested for potency prior to use in the field. The required minimum content of rabies virus antigen for vaccines was 2 IU, in accord with WHO standards. Testing revealed antigen contents ranging from 3.28 to 5.59 IU. As a result of the mass dog vaccination campaigns, human rabies cases due to dog-mediated rabies decreased from 60 in 1990 to 0 in 2000. The number of rabies cases in dogs decreased from 3,049 in 1990 to 70 cases last year.


Assuntos
Doenças do Cão/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/imunologia , Raiva/veterinária , Vacinação/veterinária , Animais , Anticorpos Antivirais/sangue , Células Cultivadas , Doenças do Cão/epidemiologia , Cães , Feminino , Humanos , Masculino , México/epidemiologia , Raiva/epidemiologia , Raiva/prevenção & controle , Vacinação/métodos , Vacinação/normas , Vacinação/estatística & dados numéricos
19.
Nat Commun ; 9(1): 4194, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305620

RESUMO

Puberty is regulated by epigenetic mechanisms and is highly sensitive to metabolic and nutritional cues. However, the epigenetic pathways mediating the effects of nutrition and obesity on pubertal timing are unknown. Here, we identify Sirtuin 1 (SIRT1), a fuel-sensing deacetylase, as a molecule that restrains female puberty via epigenetic repression of the puberty-activating gene, Kiss1. SIRT1 is expressed in hypothalamic Kiss1 neurons and suppresses Kiss1 expression. SIRT1 interacts with the Polycomb silencing complex to decrease Kiss1 promoter activity. As puberty approaches, SIRT1 is evicted from the Kiss1 promoter facilitating a repressive-to-permissive switch in chromatin landscape. Early-onset overnutrition accelerates these changes, enhances Kiss1 expression and advances puberty. In contrast, undernutrition raises SIRT1 levels, protracts Kiss1 repression and delays puberty. This delay is mimicked by central pharmacological activation of SIRT1 or SIRT1 overexpression, achieved via transgenesis or virogenetic targeting to the ARC. Our results identify SIRT1-mediated inhibition of Kiss1 as key epigenetic mechanism by which nutritional cues and obesity influence mammalian puberty.


Assuntos
Epigênese Genética , Kisspeptinas/genética , Fenômenos Fisiológicos da Nutrição , Obesidade/metabolismo , Maturidade Sexual , Sirtuína 1/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Cromatina/metabolismo , Feminino , Histonas/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Camundongos Transgênicos , Modelos Biológicos , Neurônios/metabolismo , Estado Nutricional , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Ratos , Ratos Wistar , Fatores de Tempo
20.
Environ Sci Pollut Res Int ; 24(14): 12608-12617, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27696194

RESUMO

In the present work, two kinds of hybrid polymeric-inorganic coatings containing TiO2 or SiO2 particles and prepared starting from two commercial resins (Alpha®SI30 and Bluesil®BP9710) were developed and applied to two kinds of mortars (an air-hardening calcic lime mortar [ALM] and a natural hydraulic lime mortar [HLM]) to achieve better performances in terms of water repellence and consequently damage resistance. The two pure commercial resins were also applied for comparison purposes. Properties of the coated materials and their performance were studied using different techniques such as contact angle measurements, capillary absorption test, mercury intrusion porosimetry, surface free energy, colorimetric measurements and water vapour permeability tests. Tests were also performed to determine the weathering effects on both the commercial and the hybrid coatings in order to study their durability. Thus, exposures to UV radiation, to UV radiation/condensed water cycles and to a real polluted atmospheric environment have been performed. The effectiveness of the hybrid SiO2 based coating was demonstrated, especially in the case of the HLM mortar.


Assuntos
Compostos de Cálcio , Dióxido de Silício , Materiais Revestidos Biocompatíveis , Materiais de Construção , Teste de Materiais , Óxidos , Polímeros , Propriedades de Superfície , Titânio
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