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1.
Cytokine ; 158: 155999, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35985175

RESUMO

Many cytokines have been proposed to regulate reproduction due to their actions on hypothalamic kisspeptin cells, the main modulators of gonadotropin-releasing hormone (GnRH) neurons. Hormones such as leptin, prolactin and growth hormone are good examples of cytokines that lead to Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway activation, consequently exerting effects in kisspeptin neurons. Different studies have investigated how specific components of the JAK/STAT signaling pathway affect the functions of kisspeptin cells, but the role of the suppressor of cytokine signaling 3 (SOCS3) in mediating cytokine actions in kisspeptin cells remains unknown. Cre-Loxp technology was used in the present study to ablate Socs3 expression in kisspeptin cells (Kiss1/Socs3-KO). Then, male and female control and Kiss1/Socs3-KO mice were evaluated for sexual maturation, energy homeostasis features, and fertility. It was found that hypothalamic Kiss1 mRNA expression is significantly downregulated in Kiss1/Socs3-KO mice. Despite reduced hypothalamic Kiss1 mRNA content, these mice did not present any sexual maturation or fertility impairments. Additionally, body weight gain, leptin sensitivity and glucose homeostasis were similar to control mice. Interestingly, Kiss1/Socs3-KO mice were partially protected against lipopolysaccharide (LPS)-induced body weight loss. Our results suggest that Socs3 ablation in kisspeptin cells partially prevents the sickness behavior induced by LPS, suggesting that kisspeptin cells can modulate energy metabolism in mice in certain situations.


Assuntos
Kisspeptinas , Lipopolissacarídeos , Animais , Peso Corporal/fisiologia , Citocinas/metabolismo , Feminino , Kisspeptinas/genética , Kisspeptinas/metabolismo , Leptina/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , RNA Mensageiro , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Redução de Peso
3.
Mol Cell Endocrinol ; 542: 111532, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34915098

RESUMO

Hypothalamic kisspeptin neurons are the primary modulators of gonadotropin-releasing hormone (GnRH) neurons. It has been shown that circadian rhythms driven by the suprachiasmatic nucleus (SCN) contribute to GnRH secretion. Kisspeptin neurons are potential targets of SCN neurons due to reciprocal connections with the anteroventral periventricular and rostral periventricular nuclei (AVPV/PeN) and the arcuate nucleus of the hypothalamus (ARH). Vasoactive intestinal peptide (VIP), a notable SCN neurotransmitter, modulates GnRH secretion depending on serum estradiol levels, aging or time of the day. Considering that kisspeptin neurons may act as interneurons and mediate VIP's effects on the reproductive axis, we investigated the effects of VIP on hypothalamic kisspeptin neurons in female mice during estrogen negative feedback. Our findings indicate that VIP induces a TTX-independent depolarization of approximately 30% of AVPV/PeN kisspeptin neurons in gonad-intact (diestrus) and ovariectomized (OVX) mice. In the ARH, the percentage of kisspeptin neurons that were depolarized by VIP was even higher (approximately 90%). An intracerebroventricular infusion of VIP leds to an increased percentage of kisspeptin neurons expressing the phosphoSer133 cAMP-response-element-binding protein (pCREB) in the AVPV/PeN. On the other hand, pCREB expression in ARH kisspeptin neurons was similar between saline- and VIP-injected mice. Thus, VIP can recruit different signaling pathways to modulate AVPV/PeN or ARH kisspeptin neurons, resulting in distinct cellular responses. The expression of VIP receptors (VPACR) was upregulated in the AVPV/PeN, but not in the ARH, of OVX mice compared to mice on diestrus and estradiol-primed OVX mice. Our findings indicate that VIP directly influences distinct cellular aspects of the AVPV/PeN and ARH kisspeptin neurons during estrogen negative feedback, possibly to influence pulsatile LH secretion.


Assuntos
Kisspeptinas , Peptídeo Intestinal Vasoativo , Animais , Estradiol/metabolismo , Estradiol/farmacologia , Estrogênios/metabolismo , Estrogênios/farmacologia , Retroalimentação , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/metabolismo , Camundongos , Neurônios/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Peptídeo Intestinal Vasoativo/farmacologia
4.
Life Sci ; 285: 119970, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34562435

RESUMO

Growth hormone (GH) deficiency is a common cause of late sexual maturation and fertility issues. To determine whether GH-induced effects on reproduction are associated with alterations in hypothalamic kisspeptin system, we studied the male reproduction in two distinct GH deficiency mouse models. In the first model, mice present GH deficiency secondary to arcuate nucleus of the hypothalamus (ARH) lesions induced by posnatal monosodium glutamate (MSG) injections. MSG-induced ARH lesions led to significant reductions in hypothalamic Ghrh mRNA expression and consequently growth. Hypothalamic Kiss1 mRNA expression and Kiss1-expressing cells in the ARH were disrupted in the MSG-treated mice. In contrast, kisspeptin immunoreactivity remained preserved in the anteroventral periventricular and rostral periventricular nuclei (AVPV/PeN) of MSG-treated mice. Importantly, ARH lesions caused late sexual maturation and infertility in male mice. In our second mouse model, we studied animals profound GH deficiency due to a loss-of-function mutation in the Ghrhr gene (Ghrhrlit/lit mice). Interestingly, although Ghrhrlit/lit mice exhibited late puberty onset, hypothalamic Kiss1 mRNA expression and hypothalamic kisspeptin fiber density were normal in Ghrhrlit/lit mice. Despite presenting dwarfism, the majority of Ghrhrlit/lit male mice were fertile. These findings suggest that spontaneous GH deficiency during development does not compromise the kisspeptin system. Furthermore, ARH Kiss1-expressing neurons are required for fertility, while AVPV/PeN kisspeptin expression is sufficient to allow maturation of the hypothalamic-pituitary-gonadal axis in male mice.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Hormônio do Crescimento/deficiência , Sistema Hipotálamo-Hipofisário/metabolismo , Kisspeptinas/metabolismo , Reprodução , Maturidade Sexual , Animais , Nanismo/genética , Nanismo/metabolismo , Fertilidade , Kisspeptinas/genética , Masculino , Camundongos , Neurônios/metabolismo , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo
5.
Ther Adv Respir Dis ; 14: 1753466620962665, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33357114

RESUMO

BACKGROUND AND AIMS: Expansion and morphological dysregulation of the bronchial vascular network occurs in asthmatic airways. Interleukin (IL) -17 and Rho-kinase (ROCK) are known to act in inflammation control and remodeling. Modulation of Rho-kinase proteins and IL-17 may be a promising approach for the treatment of asthma through the control of angiogenesis. Our objective was to analyze the effects of treatment with anti-IL17 and/or Rho-kinase inhibitor on vascular changes in mice with chronic allergic pulmonary inflammation. METHODS: Sixty-four BALB/c mice, with pulmonary inflammation induced by ovalbumin were treated with anti-IL17A (7.5/µg per dose, intraperitoneal) and/or Rho-kinase inhibitor (Y-27632-10 mg/kg, intranasal), 1 h before each ovalbumin challenge (22, 24, 26, and 28/days). Control animals were made to inhale saline. At the end of the protocol, lungs were removed, and morphometric analysis was performed to quantify vascular inflammatory, remodeling, and oxidative stress responses. RESULTS: Anti-IL17 or Rho-kinase inhibitor reduced the number of CD4+, CD8+, dendritic cells, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, Rho-kinase 1 and 2, transforming growth factor (TGF-ß), vascular endothelial growth factor (VEGF), nuclear factor (NF)-KappaB, iNOS, metalloproteinase (MMP)-9, MMP-12, metalloproteinase inhibitor-1 (TIMP-1), FOXP-3, signal transducer and activator of transcription 1 (STAT1) and phospho-STAT1-positive cells, and actin, endothelin-1, isoprostane, biglycan, decorin, fibronectin and the collagen fibers volume fraction compared with the ovalbumin group (p < 0.05). The combination treatment, when compared with anti-IL17, resulted in potentiation of decrease in the number of IL1ß- and dendritic cells-positive cells. When we compared the OVA-RHO inhibitor-anti-IL17 with OVA-RHO inhibitor we found a reduction in the number of CD8+ and IL-17, TGF-ß, and phospho-STAT1-positive cells and endothelin-1 in the vessels (p < 0.05). There was an attenuation in the number of ROCK 2-positive cells in the group with the combined treatment when compared with anti-IL17 or Rho-kinase inhibitor-treated groups (p < 0.05). CONCLUSION: We observed no difference in angiogenesis after treatment with Rho-kinase inhibitor and anti-IL17. Although the treatments did not show differences in angiogenesis, they showed differences in the markers involved in the angiogenesis process contributing to inflammation control and vascular remodeling.The reviews of this paper are available via the supplemental material section.


Assuntos
Asma/fisiopatologia , Inibidores Enzimáticos/farmacologia , Interleucina-17/antagonistas & inibidores , Pneumonia/fisiopatologia , Remodelação Vascular/efeitos dos fármacos , Quinases Associadas a rho/antagonistas & inibidores , Amidas/farmacologia , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Isoprostanos/metabolismo , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase/metabolismo , Piridinas/farmacologia , Remodelação Vascular/fisiologia , Quinases Associadas a rho/metabolismo
6.
J Endocrinol ; 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31470413

RESUMO

Growth hormone (GH) is a key factor in the regulation of body growth, as well as a variety of other cellular and metabolic processes. Neurons expressing kisspeptin and leptin receptors (LepR) have been shown to modulate the hypothalamic-pituitary-gonadal (HPG) axis and are considered GH-responsive. The presence of functional GH receptors (GHR) in these neural populations suggests that GH may regulate the HPG axis via a central mechanism. However, there have been no studies evaluating whether or not GH-induced intracellular signaling in the brain plays a role in the timing of puberty or mediates the ovulatory cycle. Towards the goal of understanding the influence of GH on the central nervous system as a mediator of reproductive functions, GHR ablation was induced in kisspeptin and LepR expressing cells or in the entire brain. The results demonstrated that GH signaling in specific neural populations can potentially modulate the hypothalamic expression of genes related to the reproductive system or indirectly contribute to the progression of puberty. GH action in kisspeptin cells or in the entire brain was not required for sexual maturation. On the other hand, GHR ablation in LepR cells delayed puberty progression, reduced serum leptin levels, decreased body weight gain and compromised the ovulatory cycle in some individuals, while the lack of GH effects in the entire brain prompted shorter estrous cycles. These findings suggest that GH can modulate brain components of the HPG axis, although central GH signaling is not required for the timing of puberty.

7.
Arch. endocrinol. metab. (Online) ; 63(2): 142-147, Mar.-Apr. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1001213

RESUMO

ABSTRACT Objective: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway Materials and methods: The cell line was treated with T3 at a physiological dose (10−9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. Results: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. Conclusion: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.


Assuntos
Humanos , Feminino , Tri-Iodotironina/genética , Neoplasias da Mama/genética , Adenocarcinoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Fator de Crescimento Transformador alfa/genética , Sistema de Sinalização das MAP Quinases/genética , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia , Proto-Oncogenes/genética , Neoplasias da Mama/metabolismo , RNA Mensageiro/genética , Adenocarcinoma/metabolismo , Fator de Crescimento Transformador alfa/efeitos dos fármacos , Fator de Crescimento Transformador alfa/metabolismo , Linhagem Celular Tumoral/metabolismo , Células MCF-7/metabolismo
8.
Arch Endocrinol Metab ; 63(2): 142-147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30916164

RESUMO

OBJECTIVE: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway. MATERIALS AND METHODS: The cell line was treated with T3 at a physiological dose (10-9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. RESULTS: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. CONCLUSION: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.


Assuntos
Adenocarcinoma/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases/genética , Fator de Crescimento Transformador alfa/genética , Tri-Iodotironina/genética , Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral/metabolismo , Feminino , Humanos , Células MCF-7/metabolismo , Proto-Oncogene Mas , Proto-Oncogenes/genética , RNA Mensageiro/genética , Fator de Crescimento Transformador alfa/efeitos dos fármacos , Fator de Crescimento Transformador alfa/metabolismo , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia
9.
Front Physiol ; 9: 1183, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233389

RESUMO

Background: Interleukin-17 (IL-17) and Rho-kinase (ROCK) play an important role in regulating the expression of inflammatory mediators, immune cell recruitment, hyper-responsiveness, tissue remodeling, and oxidative stress. Modulation of IL-17 and ROCK proteins may represent a promising approach for the treatment of this disease. Objective: To study the effects of an anti-IL17 neutralizing antibody and ROCK inhibitor treatments, separately and in combination, in a murine model of chronic allergy-induced lung inflammation. Methods: Sixty-four BALBc mice, were divided into eight groups (n = 8): SAL (saline-instilled); OVA (exposed-ovalbumin); SAL-RHOi (saline and ROCK inhibitor), OVA-RHOi (exposed-ovalbumin and ROCK inhibitor); SAL-anti-IL17 (saline and anti-IL17); OVA-anti-IL17 (exposed-ovalbumin and anti-IL17); SAL-RHOi-anti-IL17 (saline, ROCK inhibitor and anti-IL17); and OVA-RHOi-anti-IL17 (exposed-ovalbumin, anti-IL17, and ROCK inhibitor). A 28-day protocol of albumin treatment was used for sensitization and induction of pulmonary inflammation. The anti-IL17A neutralizing antibody (7.5 µg per treatment) was administered by intraperitoneal injection and ROCK inhibitor (Y-27632) intranasally (10 mg/kg), 1 h prior to each ovalbumin challenge (days 22, 24, 26, and 28). Results: Treatment with the anti-IL17 neutralizing antibody and ROCK inhibitor attenuated the percentage of maximal increase of respiratory system resistance and respiratory system elastance after challenge with methacholine and the inflammatory response markers evaluated (CD4+, CD8+, ROCK1, ROCK2, IL-4, IL-5, IL-6, IL-10 IL-13, IL-17, TNF-α, TGF-ß, NF-κB, dendritic cells, iNOS, MMP-9, MMP-12, TIMP-1, FOXP3, isoprostane, biglycan, decorin, fibronectin, collagen fibers content and gene expression of IL-17, VAChT, and arginase) compared to the OVA group (p < 0.05). Treatment with anti-IL17 and the ROCK inhibitor together resulted in potentiation in decreasing the percentage of resistance increase after challenge with methacholine, decreased the number of IL-5 positive cells in the airway, and reduced, IL-5, TGF-ß, FOXP3, ROCK1 and ROCK2 positive cells in the alveolar septa compared to the OVA-RHOi and OVA-anti-IL17 groups (p < 0.05). Conclusion: Anti-IL17 treatment alone or in conjunction with the ROCK inhibitor, modulates airway responsiveness, inflammation, tissue remodeling, and oxidative stress in mice with chronic allergic lung inflammation.

10.
Mol Cell Endocrinol ; 448: 55-65, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28344041

RESUMO

Previous studies have shown that kisspeptin neurons are important mediators of prolactin's effects on reproduction. However, the cellular mechanisms recruited by prolactin to affect kisspeptin neurons remain unknown. Using whole-cell patch-clamp recordings of brain slices from kisspeptin reporter mice, we observed that 20% of kisspeptin neurons in the anteroventral periventricular nucleus was indirectly depolarized by prolactin via an unknown population of prolactin responsive neurons. This effect required the phosphatidylinositol 3-kinase signaling pathway. No effects on the activity of arcuate kisspeptin neurons were observed, despite a high percentage (70%) of arcuate neurons expressing prolactin-induced STAT5 phosphorylation. To determine whether STAT5 expression in kisspeptin cells regulates reproduction, mice carrying Stat5a/b inactivation specifically in kisspeptin cells were generated. These mutants exhibited an early onset of estrous cyclicity, indicating that STAT5 transcription factors exert an inhibitory effect on the timing of puberty.


Assuntos
Kisspeptinas/metabolismo , Fator de Transcrição STAT5/metabolismo , Maturidade Sexual , Transdução de Sinais , Animais , Núcleo Arqueado do Hipotálamo/citologia , Biomarcadores/metabolismo , Ciclo Estral/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Hipotálamo Anterior/citologia , Potenciais da Membrana/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Prolactina/farmacologia , Maturidade Sexual/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
11.
J Gastroenterol ; 53(3): 276-300, mar. 2017.
Artigo em Inglês | BIGG - guias GRADE | ID: biblio-963634

RESUMO

BACKGROUND: This clinical practice guideline addresses six questions related to liberation from mechanical ventilation in critically ill adults. It is the result of a collaborative effort between the American Thoracic Society (ATS) and the American College of Chest Physicians (CHEST). METHODS: A multidisciplinary panel posed six clinical questions in a population, intervention, comparator, outcomes (PICO) format. A comprehensive literature search and evidence synthesis was performed for each question, which included appraising the quality of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. The Evidence-to-Decision framework was applied to each question, requiring the panel to evaluate and weigh the importance of the problem, confidence in the evidence, certainty about how much the public values the main outcomes, magnitude and balance of desirable and undesirable outcomes, resources and costs associated with the intervention, impact on health disparities, and acceptability and feasibility of the intervention. RESULTS: Evidence-based recommendations were formulated and graded initially by subcommittees and then modified following full panel discussions. The recommendations were confirmed by confidential electronic voting; approval required that at least 80% of the panel members agree with the recommendation. CONCLUSIONS: The panel provides recommendations regarding liberation from mechanical ventilation. The details regarding the evidence and rationale for each recommendation are presented in the American Journal of Respiratory and Critical Care Medicine and CHEST


Assuntos
Humanos , Colelitíase/diagnóstico , Colelitíase/terapia , Ácido Ursodesoxicólico , Litotripsia , Esfinterotomia Endoscópica , Colecistectomia Laparoscópica , Coledocolitíase/terapia , Abordagem GRADE
12.
Langmuir ; 32(13): 3234-41, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26982820

RESUMO

A major challenge in the design of biocidal drugs is to identify compounds with potential action on microorganisms and to understand at the molecular level their mechanism of action. In this study, thymol, a monoterpenoid found in the oil of leaves of Lippia sidoides with possible action in biological surfaces, was incorporated in lipid monolayers at the air-water interface that represented cell membrane models. The interaction of thymol with dipalmitoylphosphatidylcholine (DPPC) at the air-water interface was investigated by means of surface pressure-area isotherms, Brewster angle microscopy (BAM), polarization-modulation reflection-absorption spectroscopy (PM-IRRAS), and molecular dynamics simulation. Thymol expands DPPC monolayers, decreases their surface elasticity, and changes the morphology of the lipid monolayer, which evidence the incorporation of this compound in the lipid Langmuir film. Such incorporation could be corroborated by PM-IRRAS since some specific bands for DPPC were changed upon thymol incorporation. Furthermore, potential of mean force obtained by molecular dynamics simulations indicates that the most stable position of the drug along the lipid film is near the hydrophobic regions of DPPC. These results may be useful to understand the interaction between thymol and cell membranes during biochemical phenomena, which may be associated with its pharmaceutical properties at the molecular level.

13.
Mol Cell Endocrinol ; 423: 11-21, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26762764

RESUMO

Leptin is a permissive factor for the onset of puberty. However, changes in adiposity frequently influence leptin sensitivity. Thus, the objective of the present study was to investigate how changes in body weight, fatness, leptin levels and leptin sensitivity interact to control the timing of puberty in female mice. Pre-pubertal obesity, induced by raising C57BL/6 mice in small litters, led to an early puberty onset. Inactivation of Socs3 gene in the brain or exclusively in leptin receptor-expressing cells reduced the body weight and leptin levels at pubertal onset, and increased leptin sensitivity. Notably, these female mice exhibited significant delays in vaginal opening, first estrus and onset of estrus cyclicity. In conclusion, our findings suggest that increased leptin sensitivity did not play an important role in favoring pubertal onset in female mice. Rather, changes in pubertal body weight, fatness and/or leptin levels were more important in influencing the timing of puberty.


Assuntos
Leptina/fisiologia , Obesidade/fisiopatologia , Maturidade Sexual , Animais , Peso Corporal , Ciclo Estral/fisiologia , Feminino , Técnicas de Inativação de Genes , Hipotálamo/metabolismo , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nestina/genética , Nestina/metabolismo , Receptores para Leptina/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo
14.
Biochem Biophys Res Commun ; 467(4): 928-34, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26471302

RESUMO

Natural monoterpenes were isolated from the essential oil of Piper cernuum Vell. (Piperaceae) leaves. The crude oil and the individual monoterpenes were tested for cytotoxicity in human tumor cell lineages and B16F10-Nex2 murine melanoma cells. In the present work we demonstrate the activity of camphene against different cancer cells, with its mechanism of action being investigated in vitro and in vivo in murine melanoma. Camphene induced apoptosis by the intrinsic pathway in melanoma cells mainly by causing endoplasmic reticulum (ER) stress, with release of Ca(2+) together with HmgB1 and calreticulin, loss of mitochondrial membrane potential and up regulation of caspase-3 activity. Importantly, camphene exerted antitumor activity in vivo by inhibiting subcutaneous tumor growth of highly aggressive melanoma cells in a syngeneic model, suggesting a promising role of this compound in cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Piper/química , Terpenos/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Monoterpenos Bicíclicos , Cálcio/metabolismo , Calreticulina/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Humanos , Melanoma Experimental/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Terpenos/farmacologia
15.
Nat Prod Commun ; 10(2): 285-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25920262

RESUMO

Fractionation of the MeOH extract from leaves of Piper cernuum Vell. (Piperaceae) afforded six phenylpropanoid derivatives: 3',4'-dimethoxydihydrocinnamic acid (1), piplaroxide (2), methyl 4'-hydroxy-3',5'-dimethoxy cinnamate (3), 3',4',5'-trimethoxydihydrocinnamic acid (3), dihydropiplartine (5), and piplartine (6). The structures of isolated metabolites were characterized by NMR and MS spectral data analysis. The chemical composition of essential oil from the leaves was determined using GC/LREIMS followed by the determination of Kovats indexes. This procedure allowed the identification of nineteen terpenoids, with ß-elemene (7), bicyclogermacrene (8), germacrene D (9), and (E)-caryophyllene (10) as the main compounds. Compounds 1 and 3-6 displayed no in vitro cytotoxicity against cancer cell lineages B16F10-Nex2, U87, HeLa, HL-60, HCT, and A2058 while 2 showed moderate activity against B16F10-Nex2 and HL-60 lines. Otherwise, compounds 7-10 displayed high cytotoxic activity. Evaluation against non-tumorigenic HFF cells indicated a reduced selectivity of compounds 7-10 to tumoral cells. No antileishmanial activity on macrophages infected with L. (L.) amnazonensis was found for the crude MeOH extract and compounds 1-6. The crude essential oil and compounds 7-10 reduced parasitism and eliminated the majority of infected and non-infected cells at 50 µg/mL.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antiprotozoários/farmacologia , Óleos Voláteis/farmacologia , Piper/química , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antiprotozoários/química , Linhagem Celular Tumoral , Humanos , Leishmania/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos , Estrutura Molecular , Óleos Voláteis/química , Extratos Vegetais/química , Folhas de Planta/química , Óleos de Plantas/química
16.
Sci Rep ; 4: 6046, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25116593

RESUMO

Being an atomically thin material, graphene is known to be extremely susceptible to its environment, including defects and phonons in the substrate on which it is placed as well as gas molecules that surround it. Thus, any device design using graphene has to take into consideration all surrounding components, and device performance needs to be evaluated in terms of environmental influence. However, no methods have been established to date to readily measure the density and distribution of external perturbations in a quantitative and non-destructive manner. Here, we present a rapid and non-contact method for visualizing the distribution of molecular adsorbates on graphene semi-quantitatively using terahertz time-domain spectroscopy and imaging. We found that the waveform of terahertz bursts emitted from graphene-coated InP sensitively changes with the type of atmospheric gas, laser irradiation time, and ultraviolet light illumination. The terahertz waveform change is explained through band structure modifications in the InP surface depletion layer due to the presence of localized electric dipoles induced by adsorbed oxygen. These results demonstrate that terahertz emission serves as a local probe for monitoring adsorption and desorption processes on graphene films and devices, suggesting a novel two-dimensional sensor for detecting local chemical reactions.

17.
Molecules ; 19(6): 7528-42, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24914898

RESUMO

Bioactivity-guided fractionation of an antimicrobial active extract from twigs of Baccharis retusa C. DC. (Asteraceae) yielded the flavanone 5,4'-dihydroxy-7-methoxy-flavanone (sakuranetin) as responsible for the detected activity. The structure of the bioactive compound was established on the basis of spectroscopic data analysis, including NMR and MS. Additionally, the structure of a new crystal form of sakuranetin was confirmed by X-ray diffratometry. The minimum inhibitory concentrations (MIC) of isolated compound were determined against pathogenic yeast belonging to the genus Candida (six species), Cryptococcus (two species/four serotypes) and S. cerevisiae BY 4742 (S288c background) and ranged from 0.32 to 0.63 µg/µL. Our results showed that sakuranetin, which structure was fully characterized, could be used as a tool for the design of novel and more efficacious antifungal agents.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Asteraceae/química , Flavonoides/química , Flavonoides/farmacologia , Candida/efeitos dos fármacos , Cryptococcus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Saccharomyces cerevisiae/efeitos dos fármacos
18.
Transplant Proc ; 46(4): 1107-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24815140

RESUMO

BACKGROUND: Hepatic ischemia-reperfusion injury (IRI) is a serious complication affecting liver function and postoperative course after liver transplantation. Thrombomodulin (TM) has been known to have anticoagulant and anti-inflammatory activities exerting a cytoprotective effect. We evaluated the cytoprotective effect of recombinant human soluble TM (rhsTM) on the remnant liver exposed to IRI after 70% hepatectomy in rats, which was the simulated model of small-for-size graft in living donor liver transplantation. MATERIALS AND METHODS: A Wistar rat underwent 70% hepatectomy followed by 20-minute IRI for the remnant liver. rhsTM (1 mg/kg) (TM group) or saline (control group) was intravenously administered 30 minutes before operation. RESULTS: Alanine aminotransaminase levels were more significantly decreased during the 24 hours after operation in the TM group than in control group, especially at 6 hours. Intrahepatic infiltration of macrophages/monocytes (ED-1 immunohistochemical staining) at 6 hours was significantly decreased in the TM group compared to the control group. The number of proliferating cell nuclear antigen-positive cells at 12 hours (hepatocyte proliferation) was significantly higher in the TM group than in the control group; although liver weight 7 days after operation did not differ between the two groups. Hepatocyte apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, also known as TUNEL assay) at 24 hours was more significantly diminished in the TM group than in the control group. CONCLUSION: These results suggest that rshTM attenuates hepatocyte injury through its anti-inflammatory effect, and promotes hepatocyte proliferation in the reduced-size liver exposed to hepatic IRI.


Assuntos
Hepatectomia , Transplante de Fígado/métodos , Fígado/efeitos dos fármacos , Doadores Vivos , Substâncias Protetoras/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Trombomodulina/administração & dosagem , Administração Intravenosa , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/sangue , Proliferação de Células/efeitos dos fármacos , Citoproteção , Modelos Animais de Doenças , Humanos , Fígado/irrigação sanguínea , Fígado/patologia , Regeneração Hepática/efeitos dos fármacos , Masculino , Tamanho do Órgão , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/patologia , Fatores de Tempo
19.
Transplant Proc ; 46(3): 716-20, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767332

RESUMO

BACKGROUND: In deceased-donor liver transplantation settings, post-transplantation acute renal failure with the induction of renal replacement therapy (RRT) is known to have negative effects on graft and patient survivals. However, the impact of RRT in living-donor liver transplantation (LDLT) has not been well investigated. The aim of this study was to elucidate risk factors requiring RRT and prognostic factors after its induction. METHODS: Clinical data on the consecutive 113 adult patients who underwent LDLT from March 2002 to May 2013 were retrospectively reviewed. They were divided into 2 groups: RRT (n = 33) and Non-RRT (n = 80). The primary reasons for receiving RRT were hepatorenal syndrome (n = 17), sepsis (n = 12), and renal hypoperfusion (n = 4). RESULTS: Although there were no significant differences in age or sex, the Model for End-Stage Liver Disease (MELD) score was significantly higher in the RRT group than in the Non-RRT group (23 ± 13 vs 16 ± 7; P = .002). The graft-recipient weight ratio (GRWR) was significantly lower in the RRT group (0.86 ± 0.3 vs 0.99 ± 0.2; P = .025). The 1- and 5-year patient survival rates were significantly higher in the Non-RRT group than in the RRT group (respectively, 91.3% and 84.3% vs 42.9% and 25.5%; P < .001). In multivariate analysis, independent risk factors for receiving RRT were MELD score >20 (P = .044) and GRWR <0.7 (P = .039). In the RRT group, donor age >50 years (P = .042) and preoperative serum creatinine level >1.5 mg/dL (P = .049) were significant prognostic risk factors. CONCLUSIONS: In adult LDLT patients, the induction of RRT after LDLT was a negative predictor of survival. In addition to the preoperative recipient's condition, donor factors including graft size and donor age influenced prognosis after the induction of RRT.


Assuntos
Transplante de Fígado , Doadores Vivos , Terapia de Substituição Renal , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de Sobrevida
20.
Transplant Proc ; 46(3): 804-10, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24767353

RESUMO

BACKGROUND: Late renal dysfunction (LRD) after liver transplantation develops due to several factors such as viral hepatitis, calcineurin inhibitor, diabetes mellitus, and hypertension. The aim of our study was to clarify the risk factors for LRD after living donor liver plantation (LDLT) by using simple criteria for LRD and paying special attention to the significance of renal biopsy. PATIENTS AND METHODS: Among the 98 recipients undergoing LDLT between March 2002 and June 2008, there were 77 patients who survived more than 1 year and had been followed at our clinic. LRD was simply defined as a postoperative serum creatinine level of 1.5/L or more at any point in time after 1 year from undergoing LDLT. The perioperative risk factors for developing LRD after LDLT were analyzed by uni- and multivariate analyses, and regardless of serum creatinine level, a renal biopsy was indicated when the patient developed clinical symptoms. RESULTS: Comparing the risk factors between 22 patients with LRD and 55 without LRD, univariate analysis revealed recipient's age, generation, hypertension, hepatitis C virus (HCV) antibody-positive, pretransplantation serum creatinine level, and graft-to-recipient weight ratio to be significant risk factors. By multivariate analysis, HCV and hypertension were selected as independent risk factors. Renal biopsy was indicated in the 4 patients with proteinuria, all of whom were positive for HCV. However, by histologic and/or electron micrographic analyses, only 1 patient was diagnosed with HCV-related membranous proliferative nephritis, 1 with diabetic nephropathy, and 2 with drug (tacrolimus) -induced renal dysfunction. CONCLUSION: Although HCV and hypertension were determined to be independent risk factors for LRD after LDLT, a renal biopsy should be performed when clinical symptoms develop regardless of creatinine levels to provide appropriate treatment.


Assuntos
Hepatite C/complicações , Hipertensão/complicações , Rim/fisiopatologia , Transplante de Fígado/efeitos adversos , Doadores Vivos , Adulto , Idoso , Biópsia , Feminino , Humanos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
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