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1.
Dev Dyn ; 250(6): 880-895, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32885536

RESUMO

BACKGROUND: Regeneration of complex patterned structures is well described among, although limited to a small sampling of, amphibians. This limitation impedes our understanding of the full range of regenerative competencies within this class of vertebrates, according to phylogeny, developmental life stage, and age. To broaden the phylogenetic breath of this research, we characterized the regenerative capacity of the Texas blind salamander (Eurycea rathbuni), a protected salamander native to the Edwards Aquifer of San Marcos, Texas and colonized by the San Marcos Aquatic Resource Center. As field observations suggested regenerative abilities in this population, the forelimb stump of a live captured female was amputated in the hopes of restoring the structure, and thus locomotion in the animal. Tails were clipped from two males to additionally document tail regeneration. RESULTS: We show that the Texas blind salamander exhibits robust limb and tail regeneration, like all other studied Plethodontidae. Regeneration in this species is associated with wound epithelium formation, blastema formation, and subsequent patterning and differentiation of the regenerate. CONCLUSIONS: The study has shown that the Texas blind salamander is a valuable model to study regenerative processes, and that therapeutic surgeries offer a valuable means to help maintain and conserve this vulnerable species.


Assuntos
Membro Anterior/fisiologia , Regeneração/fisiologia , Cauda/fisiologia , Urodelos/fisiologia , Animais , Diferenciação Celular/fisiologia , Feminino , Masculino , Filogenia , Urodelos/crescimento & desenvolvimento
2.
Dev Biol ; 451(2): 146-157, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31026439

RESUMO

Some organisms, such as the Mexican axolotl, have the capacity to regenerate complicated biological structures throughout their lives. Which molecular pathways are sufficient to induce a complete endogenous regenerative response in injured tissue is an important question that remains unanswered. Using a gain-of-function regeneration assay, known as the Accessory Limb Model (ALM), we and others have begun to identify the molecular underpinnings of the three essential requirements for limb regeneration; wounding, neurotrophic signaling, and the induction of pattern from cells that retain positional memory. We have previously shown that treatment of Mexican axolotls with exogenous retinoic acid (RA) is sufficient to induce the formation of complete limb structures from blastemas that were generated by deviating a nerve bundle into an anterior-located wound site on the limb. Here we show that these ectopic structures are capable of regenerating and inducing new pattern to form when grafted into new anterior-located wounds. We additionally found that the expression of Alx4 decreases, and Shh expression increases in these anterior located blastemas, but not in the mature anterior tissues, supporting the hypothesis that RA treatment posteriorizes blastema tissue. Based on these and previous observations, we used the ALM assay to test the hypothesis that a complete regenerative response can be generated by treating anterior-located superficial limb wounds with a specific combination of growth factors at defined developmental stages. Our data shows that limb wounds that are first treated with a combination of FGF-2, FGF-8, and BMP-2, followed by RA treatment of the resultant mid-bud stage blastema, will result in the generation of limbs with complete proximal/distal and anterior/posterior limb axes. Thus, the minimal signaling requirements from the nerve and a positional disparity are achieved with the application of this specific combination of signaling molecules.


Assuntos
Ambystoma mexicanum/fisiologia , Transdução de Sinais , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Extremidades/fisiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Regeneração , Tretinoína/metabolismo
3.
Gerontology ; 66(3): 212-222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31779024

RESUMO

Loss of regenerative capacity is a normal part of aging. However, some organisms, such as the Mexican axolotl, retain striking regenerative capacity throughout their lives. Moreover, the development of age-related diseases is rare in this organism. In this review, we will explore how axolotls are used as a model system to study regenerative processes, the exciting new technological advancements now available for this model, and how we can apply the lessons we learn from studying regeneration in the axolotl to understand, and potentially treat, age-related decline in humans.


Assuntos
Envelhecimento/fisiologia , Ambystoma mexicanum/fisiologia , Regeneração/fisiologia , Animais , Humanos
4.
Int J Mol Sci ; 19(12)2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30486286

RESUMO

Disease of, or trauma to, the human jaw account for thousands of reconstructive surgeries performed every year. One of the most popular and successful treatment options in this context involves the transplantation of bone tissue from a different anatomical region into the affected jaw. Although, this method has been largely successful, the integration of the new bone into the existing bone is often imperfect, and the integration of the host soft tissues with the transplanted bone can be inconsistent, resulting in impaired function. Unlike humans, several vertebrate species, including fish and amphibians, demonstrate remarkable regenerative capabilities in response to jaw injury. Therefore, with the objective of identifying biological targets to promote and engineer improved outcomes in the context of jaw reconstructive surgery, we explore, compare and contrast the natural mechanisms of endogenous jaw and limb repair and regeneration in regenerative model organisms. We focus on the role of different cell types as they contribute to the regenerating structure; how mature cells acquire plasticity in vivo; the role of positional information in pattern formation and tissue integration, and limitations to endogenous regenerative and repair mechanisms.


Assuntos
Osso e Ossos/fisiologia , Modelos Biológicos , Regeneração/fisiologia , Animais , Padronização Corporal , Cabeça , Humanos , Medicina Regenerativa
5.
Cell Mol Life Sci ; 73(19): 3665-76, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27173059

RESUMO

Obesity is associated with the establishment and maintenance of a low grade, chronically inflamed state in the white adipose tissue (WAT) of the body. The WAT macrophage population is a major cellular participant in this inflammatory process that significantly contributes to the pathophysiology of the disease, with the adipose depots of obese individuals, relative to lean counterparts, having an elevated number of macrophages that are skewed towards a pro-inflammatory phenotype. Alterations in the WAT lipid micro-environment, and specifically the availability of free fatty acids, are believed to contribute towards the obesity-related quantitative and functional changes observed in these cells. This review specifically addresses the involvement of the five G-protein coupled free fatty acid receptors which bind exogenous FFAs and signal in macrophages. Particular focus is placed on the involvement of these receptors in macrophage migration and cytokine production, two important aspects that modulate inflammation.


Assuntos
Tecido Adiposo Branco/citologia , Ácidos Graxos/metabolismo , Macrófagos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Adiposidade , Animais , Humanos
6.
Malar J ; 15: 32, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26791088

RESUMO

BACKGROUND: Malaria remains a global health problem and the majority of deaths are caused by Plasmodium falciparum parasites. Due to the rapid emergence of drug-resistant strains, novel avenues of research on the biology of the parasite are needed. The massive proliferation of asexual, intra-erythrocytic parasites every 48 h could kill the human host prior to transmission of slow-developing gametocytes to the mosquito vector. A self-induced P. falciparum programmed cell death mechanism has been hypothesized to maintain this balance between the parasite and its two hosts, but molecular participants of the cell death pathway in P. falciparum have not been characterized. Proteins with SWIB/MDM2 domains play a key role in metazoan programmed cell death and this study provides the first evaluation of two parasite SWIB/MDM2 homologues, PF3D7_0518200 (PfMDM2) and PF3D7_0611400 (PfSWIB). METHODS: The function of these proteins was assessed by predicting their structural topology with the aid of bioinformatics and determining their location within live transgenic parasites, expressing green fluorescent protein-tagged PfMDM2 and PfSWIB under normal and elevated temperatures, which mimic fever and which are known to induce a programmed cell death response. Additionally, P. falciparum phage display library technology was used to identify binding partners for the two parasite SWIB/MDM2 domains. RESULTS: Structural features of the SWIB/MDM2 domains of PfMDM2 and PfSWIB, suggested that they are chromatin remodelling factors. The N-terminal signal sequence of PfMDM2 directed the protein to the mitochondrion under both normal and heat stress conditions. Plasmodium falciparum phage display library technology revealed that the C-terminal SWIB/MDM2 domain of PfMDM2 interacted with a conserved protein containing a LisH domain. PfSWIB localized to the cytoplasm under normal growth conditions, while approximately 10% of the heat-stressed trophozoite-stage parasites presented a rapid but short-lived nuclear localization pattern. Two PfSWIB binding partners, a putative Aurora-related kinase and a member of the inner membrane complex, were identified. CONCLUSION: These novel data provide insight into the function of two parasite SWIB/MDM2 homologues and suggest that PfMDM2 plays a role within the mitochondrion and that PfSWIB is involved in a stage-specific, heat-stress, response pathway.


Assuntos
Malária Falciparum/parasitologia , Plasmodium falciparum/patogenicidade , Apoptose/fisiologia , Biologia Computacional/métodos , Resposta ao Choque Térmico/fisiologia , Biblioteca de Peptídeos , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas de Protozoários/metabolismo
7.
J Hepatol ; 58(6): 1125-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23402745

RESUMO

BACKGROUND & AIMS: Bacterial infections commonly occur in decompensated cirrhosis resulting from bacterial translocation from the intestine. We studied the role of intestinal macrophages and the epithelial barrier in cirrhosis. METHODS: Forty-four patients with NASH/ASH cirrhosis (decompensated n=29, compensated n=15) and nineteen controls undergoing endoscopy were recruited. Serum was obtained and LPS and LBP levels determined. Intestinal macrophages were characterized by flow cytometry, immunohistochemistry, and nitric oxide (NO) production measured in supernatant of cultured duodenal samples. Quantitative RT-PCR was performed on duodenal biopsies assessing 84 inflammatory genes. Protein levels of cytokines/chemokines were assessed in serum and supernatant. The duodenal wall was assessed by electron microscopy, tight junction protein expression determined by RT-PCR, immunohistochemistry, and Western blot and, functional analysis performed by transepithelial resistance measurement and permeability studies. RESULTS: Increased plasma LPS, LBP levels and higher numbers of duodenal CD33(+)/CD14(+)/Trem-1(+) macrophages, synthesizing iNOS and secreting NO were present in decompensated cirrhosis. Upregulation of IL-8, CCL2, CCL13 at the transcriptional level, and increased IL-8, and IL-6 were detected in supernatant and serum in cirrhosis. IL-6 and IL-8 co-localised with iNOS(+) and CD68(+), but not with CD11c(+) cells. Electron microscopy demonstrated an intact epithelial barrier. Increased Claudin-2 was detected by Western blot and immunohistochemistry, while decreased transepithelial resistance and increased duodenal permeability were detected in decompensated cirrhosis. CONCLUSIONS: Our study shows the presence of activated CD14(+)Trem-1(+)iNOS(+) intestinal macrophages, releasing IL-6, NO, and increased intestinal permeability in patients with cirrhosis, suggesting that these cells may produce factors capable of enhancing permeability to bacterial products.


Assuntos
Interleucina-6/metabolismo , Intestinos/imunologia , Cirrose Hepática/imunologia , Ativação de Macrófagos , Macrófagos/imunologia , Óxido Nítrico/metabolismo , Idoso , Feminino , Humanos , Mucosa Intestinal/metabolismo , Receptores de Lipopolissacarídeos/análise , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/metabolismo , Permeabilidade
8.
Front Cell Dev Biol ; 11: 1152510, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37333984

RESUMO

Introduction: Little is known about how the newly regenerated limb tissues in the Mexican axolotl seamlessly integrate with the remaining stump tissues to form a functional structure, and why this doesn't occur in some regenerative scenarios. In this study, we evaluate the phenomenological and transcriptional characteristics associated with integration failure in ectopic limb structures generated by treating anterior-located ectopic blastemas with Retinoic Acid (RA) and focusing on the "bulbus mass" tissue that forms between the ectopic limb and the host site. We additionally test the hypothesis that the posterior portion of the limb base contains anterior positional identities. Methods: The positional identity of the bulbus mass was evaluated by assaying regenerative competency, the ability to induce new pattern in the Accessory Limb Model (ALM) assay, and by using qRTPCR to quantify the relative expression of patterning genes as the bulbus mass deintegrates from the host site. We additionally use the ALM and qRTPCR to analyze the distribution of anterior and posterior positional identities along the proximal/distal limb axis of uninjured and regenerating limbs. Results: The bulbus mass regenerates limb structures with decreased complexity when amputated and is able to induce complex ectopic limb structure only when grafted into posterior-located ALMs. Expressional analysis shows significant differences in FGF8, BMP2, TBX5, Chrdl1, HoxA9, and HoxA11 expression between the bulbus mass and the host site when deintegration is occuring. Grafts of posterior skin from the distal limb regions into posterior ALMs at the base of the limb induce ectopic limb structures. Proximally-located blastemas express significantly less HoxA13 and Ptch1, and significantly more Alx4 and Grem1 than distally located blastemas. Discussion: These findings show that the bulbus mass has an anterior-limb identity and that the expression of limb patterning genes is mismatched between the bulbus mass and the host limb. Our findings additionally show that anterior positional information is more abundant at the limb base, and that anterior patterning genes are more abundantly expressed in proximally located blastemas compared to blastemas in the more distal regions of the limb. These experiments provide valuable insight into the underlying causes of integration failure and further map the distribution of positional identities in the mature limb.

9.
PLoS One ; 16(3): e0248051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33667253

RESUMO

The Mexican Axolotl is able to regenerate missing limb structures in any position along the limb axis throughout its life and serves as an excellent model to understand the basic mechanisms of endogenous regeneration. How the new pattern of the regenerating axolotl limb is established has not been completely resolved. An accumulating body of evidence indicates that pattern formation occurs in a hierarchical fashion, which consists of two different types of positional communications. The first type (Type 1) of communication occurs between connective tissue cells, which retain memory of their original pattern information and use this memory to generate the pattern of the regenerate. The second type (Type 2) of communication occurs from connective tissue cells to other cell types in the regenerate, which don't retain positional memory themselves and arrange themselves according to these positional cues. Previous studies suggest that molecules within the extracellular matrix (ECM) participate in pattern formation in developing and regenerating limbs. However, it is unclear whether these molecules play a role in Type 1 or Type 2 positional communications. Utilizing the Accessory Limb Model, a regenerative assay, and transcriptomic analyses in regenerates that have been reprogrammed by treatment with Retinoic Acid, our data indicates that the ECM likely facilities Type-2 positional communications during limb regeneration.


Assuntos
Matriz Extracelular/metabolismo , Membro Posterior/fisiologia , Regeneração/fisiologia , Ambystoma mexicanum , Animais
10.
Elife ; 102021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34779399

RESUMO

The mechanisms that regulate growth and size of the regenerating limb in tetrapods such as the Mexican axolotl are unknown. Upon the completion of the developmental stages of regeneration, when the regenerative organ known as the blastema completes patterning and differentiation, the limb regenerate is proportionally small in size. It then undergoes a phase of regeneration that we have called the 'tiny-limb' stage, which is defined by rapid growth until the regenerate reaches the proportionally appropriate size. In the current study we have characterized this growth and have found that signaling from the limb nerves is required for its maintenance. Using the regenerative assay known as the accessory limb model (ALM), we have found that growth and size of the limb positively correlates with nerve abundance. We have additionally developed a new regenerative assay called the neural modified-ALM (NM-ALM), which decouples the source of the nerves from the regenerating host environment. Using the NM-ALM we discovered that non-neural extrinsic factors from differently sized host animals do not play a prominent role in determining the size of the regenerating limb. We have also discovered that the regulation of limb size is not autonomously regulated by the limb nerves. Together, these observations show that the limb nerves provide essential cues to regulate ontogenetic allometric growth and the final size of the regenerating limb.


Humans' ability to regrow lost or damaged body parts is relatively limited, but some animals, such as the axolotl (a Mexican salamander), can regenerate complex body parts, like legs, many times over their lives. Studying regeneration in these animals could help researchers enhance humans' abilities to heal. One way to do this is using the Accessory Limb Model (ALM), where scientists wound an axolotl's leg, and study the additional leg that grows from the wound. The first stage of limb regeneration creates a new leg that has the right structure and shape. The new leg is very small so the next phase involves growing the leg until its size matches the rest of the animal. This phase must be controlled so that the limb stops growing when it reaches the right size, but how this regulation works is unclear. Previous research suggests that the number of nerves in the new leg could be important. Wells et al. used a ALM to study how the size of regenerating limbs is controlled. They found that changing the number of nerves connected to the new leg altered its size, with more nerves leading to a larger leg. Next, Wells et al. created a system that used transplanted nerve bundles of different sizes to grow new legs in different sized axolotls. This showed that the size of the resulting leg is controlled by the number of nerves connecting it to the CNS. Wells et al. also showed that nerves can only control regeneration if they remain connected to the central nervous system. These results explain how size is controlled during limb regeneration in axolotls, highlighting the fact that regrowth is directly controlled by the number of nerves connected to a regenerating leg. Much more work is needed to reveal the details of this process and the signals nerves use to control growth. It will also be important to determine whether this control system is exclusive to axolotls, or whether other animals also use it.


Assuntos
Ambystoma mexicanum/fisiologia , Membro Anterior/fisiologia , Regeneração , Animais , Diferenciação Celular
11.
Biosystems ; 183: 103989, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31295535

RESUMO

In 1901 T.H. Morgan proposed in "Regeneration" that pattern formation in amphibian limb regeneration is a stepwise process. Since, biologist have continued to piece together the molecular components of this process to better understand the "patterning code" responsible for regenerate formation. Within this context, several different models have been proposed; however, all are based on one of two underlying hypotheses. The first is the "morphogen hypothesis" that dictates that pattern emerges from localized expression of signaling molecules, which produce differing position-specific cellular responses in receptive cells depending on the intensity of the signal. The second hypothesis is that cells in the remaining tissues retain memory of their patterning information, and use this information to generate new cells with the missing positional identities. A growing body of evidence supports the possibility that these two mechanisms are not mutually exclusive. Here, we propose our theory of hierarchical pattern formation, which consists of 4 basic steps. The first is the existence of cells with positional memory. The second is the communication of positional information through cell-cell interactions in a regeneration-permissive environment. The third step is the induction of molecular signaling centers. And the last step is the interpretation of these signals by specialized cell types to ultimately restore the limb in its entirety. Biological codes are intertwined throughout this model, and we will discuss their multiple roles and mechanisms.


Assuntos
Anfíbios/crescimento & desenvolvimento , Padronização Corporal , Extremidades/crescimento & desenvolvimento , Regeneração , Animais , Caenorhabditis elegans , Comunicação Celular , Fibroblastos/fisiologia , Humanos , Modelos Biológicos , Morfogênese , Transdução de Sinais , Urodelos
12.
Mech Dev ; 153: 1-9, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30096415

RESUMO

Urodele amphibians such as the axolotl regenerate complete limbs as adults, and understanding how the "blueprint", or pattern, of the regenerate is established and manipulated are areas of intense interest. Nutrient signaling plays an important role in pattern formation during regeneration. Retinoic acid signaling is the most characterized pathway during this process. Exogenous retinoic acid (RA) reprograms the pattern information in regenerating cells to a more posterior, ventral, and proximal identity. Vitamin D signaling shares several molecular similarities with RA and has been shown to alter pattern formation during zebrafish pectoral fin regeneration. To determine if exogenous Vitamin D signaling is capable of reprograming pattern in the axolotl limb blastema, we treated regenerating limbs with a potent Vitamin D agonist. Under the studied conditions, exogenous Vitamin D did not act in a manner similar to RA and failed to proximalize the pattern of the resulting regenerates. The Vitamin D treatment did result in several skeletal defects during regeneration, including carpal fusions along the A/P axis; failure to integrate the newly regenerated tissue with the existing tissue, formation of ectopic nodules of cartilage at the site of amputation, and altered bone morphology in uninjured skeletal tissue.


Assuntos
Ambystoma mexicanum/fisiologia , Padronização Corporal/efeitos dos fármacos , Osso e Ossos/embriologia , Diferenciação Celular/efeitos dos fármacos , Extremidades/fisiologia , Regeneração/efeitos dos fármacos , Transdução de Sinais , Vitamina D/farmacologia , Amputação Cirúrgica , Animais , Osso e Ossos/efeitos dos fármacos , Ergocalciferóis/farmacologia , Organogênese/efeitos dos fármacos , Fenótipo
13.
Data Brief ; 15: 970-974, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29159235

RESUMO

Trimethylation of Histone 3 lysine 27 (H3K27me3) is a chromatin modification that is associated with transcriptional repression (Cao et al., 2002; Sarma et al., 2008; Pengelly et al., 2013) [1], [2], [3]. In this article we performed anti-H3K27me3 Chromosomal Immunoprecipitation (ChIP-PCR), to detect the abundance of H3K27me3 marks on Ef1-alpha, cyp26A, HoxC10, HoxD10 and HoxD11 in the Xenopus XTC cell line. We also performed RT-PCR for these genes to determine whether their expression is detectable in the XTC cell culture. The data we present here are the fold enrichment of Ef1-alpha, cyp26A, HoxC10, HoxD10 and HoxD11 on anti-H3K27me3 ChIP compared to no antibody controls. We also present RT-PCR data on the above listed genes.

14.
PLoS One ; 12(10): e0185292, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29023511

RESUMO

The nuclear landscape plays an important role in the regulation of tissue and positional specific genes in embryonic and developing cells. Changes in this landscape can be dynamic, and are associated with the differentiation of cells during embryogenesis, and the de-differentiation of cells during induced pluripotent stem cell (iPSC) formation and in many cancers. However, tools to quantitatively characterize these changes are limited, especially in the in vivo context, where numerous tissue types are present and cells are arranged in multiple layers. Previous tools have been optimized for the monolayer nature of cultured cells. Therefore, we present a new algorithm to quantify the condensation of chromatin in two in vivo systems. We first developed this algorithm to quantify changes in chromatin compaction and validated it in differentiating spermatids in zebrafish testes. Our algorithm successfully detected the typical increase in chromatin compaction as these cells differentiate. We then employed the algorithm to quantify the changes that occur in amphibian limb cells as they participate in a regenerative response. We observed that the chromatin in the limb cells de-compacts as they contribute to the regenerating organ. We present this new tool as an open sourced software that can be readily accessed and optimized to quantify chromatin compaction in complex multi-layered samples.


Assuntos
Algoritmos , Núcleo Celular/metabolismo , Cromatina/química , Extremidades/embriologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Peixe-Zebra/genética , Ambystoma mexicanum , Animais , Diferenciação Celular , Células Cultivadas , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Desenvolvimento Embrionário/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
15.
PLoS One ; 8(9): e71935, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24039728

RESUMO

2-Methoxyestradiol (2ME2) is a naturally occurring estradiol metabolite which possesses antiproliferative, antiangiogenic and antitumor properties. However, due to its limited biological accessibility, synthetic analogues have been synthesized and tested in attempt to develop drugs with improved oral bioavailability and efficacy. The aim of this study was to evaluate the antiproliferative effects of three novel in silico-designed sulphamoylated 2ME2 analogues on the HeLa cervical adenocarcinoma cell line and estrogen receptor-negative breast adenocarcinoma MDA-MB-231 cells. A dose-dependent study (0.1-25 µM) was conducted with an exposure time of 24 hours. Results obtained from crystal violet staining indicated that 0.5 µM of all 3 compounds reduced the number of cells to 50%. Lactate dehydrogenase assay was used to assess cytotoxicity, while the mitotracker mitochondrial assay and caspase-6 and -8 activity assays were used to investigate the possible occurrence of apoptosis. Tubulin polymerization assays were conducted to evaluate the influence of these sulphamoylated 2ME2 analogues on tubulin dynamics. Double immunofluorescence microscopy using labeled antibodies specific to tyrosinate and detyrosinated tubulin was conducted to assess the effect of the 2ME2 analogues on tubulin dynamics. An insignificant increase in the level of lactate dehydrogenase release was observed in the compounds-treated cells. These sulphamoylated compounds caused a reduction in mitochondrial membrane potential, cytochrome c release and caspase 3 activation indicating apoptosis induction by means of the intrinsic pathway in HeLa and MDA-MB-231 cells. Microtubule depolymerization was observed after exposure to these three sulphamoylated analogues.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Estradiol/análogos & derivados , 2-Metoxiestradiol , Adenocarcinoma , Caspase 3/metabolismo , Forma Celular/efeitos dos fármacos , Citocromos c/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Ativação Enzimática , Estradiol/farmacologia , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Microtúbulos/metabolismo , Multimerização Proteica/efeitos dos fármacos , Sulfonamidas/farmacologia , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia
16.
J Asthma Allergy ; 3: 123-30, 2010 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21437046

RESUMO

The gastrointestinal tract (GIT) of vertebrates is composed of several distinct compartments and glands as well as an extensive mucosal surface. Its primary function is that of chemical and physical digestion of food and the absorption of nutrients; however, due to its continual antigen exposure, the GIT also has an important defensive immunological function. The GIT's immunological participation is facilitated by the mucosa-associated lymphoid tissues, thought to share the mucosal immunological system with the respiratory mucosa-associated lymphoid tissues. As a result of this shared mucosal immunity, it has been hypothesized that bronchial asthma may be able to affect the body's GIT in the same pathophysiological manner as the airways and lungs. Here we discuss the link between bronchial asthma and pathophysiological features in the GIT - including leukocyte influx, goblet cell alterations, fibrosis, and epithelial and villous atrophy.

17.
Anat Sci Int ; 84(3): 210-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19214657

RESUMO

Platelets and fibrin play an important role in allergic processes, including allergic asthma. The asthmatic BALB/c mouse model was used to induce asthma, and asthmatic mice were treated with the anti-inflammatory plant Withania somnifera, separately and in combination with the antioxidant selenium. Selenium is an important supplement in asthma, because asthmatics may have a selenium deficiency. Hydrocortisone was used as positive control. Results indicate control mice possess major thick fibers, minor thin fibers, and tight round activated platelets with typical pseudopodia formation. Minor fibers of asthmatic mice have a netlike appearance covering the major fibers whereas the platelets form loosely connected, granular aggregates. Hydrocortisone made the fibrin more fragile and platelet morphology changes from a tight activated platelet to a more granular activated platelet, not closely fused to each other. The plant extracts, separately and in combination with selenium did not affect the fragility of the fibrin and reversed the formation of the dense minor netlike layer over the major fibers, and the platelets formed a dense aggregate. Asthmatic mice treated with selenium showed a dense minor fibrin layer; however, the platelets formed a dense aggregate. We conclude that the anti-inflammatory products affect the stability of fibrin networks but not platelet stability (seen with hydrocortisone). Selenium does not affect the stability of the fibrin networks, but affects platelet stability. These results suggests that asthmatic patients should indeed use an antioxidant supplement, e.g. selenium, because it stabilizes activated platelets, together with anti-inflammatory products.


Assuntos
Antioxidantes/farmacologia , Plaquetas/efeitos dos fármacos , Fibrina/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Selênio/farmacologia , Withania , Animais , Antioxidantes/uso terapêutico , Asma/tratamento farmacológico , Plaquetas/ultraestrutura , Quimioterapia Combinada , Feminino , Fibrina/ultraestrutura , Contagem de Leucócitos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Extratos Vegetais/uso terapêutico , Selênio/uso terapêutico
18.
Int. j. morphol ; 29(4): 1341-1350, dic. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-627013

RESUMO

Scientific literature, although limited in this area, supports the hypothesis that asthma, by means of selective leukocyte trafficking between the various mucosal and glandular sites of the body, can have the same pathophysiological effects on the stomach as the airways. This study aimed to determine if asthma, in the absence and presence of various asthma therapies (Hydrocortisone and Modul8TM), imparted any morphological alteration on the stomach parietal and chief cells. The BALB/c murine asthmatic mouse model was the model of choice in this study. The asthma induction protocol as well as the asthma therapies were proved to be effective with the aid of bronchial lavage fluid leukocyte quantification. Fundic and pyloric biopsies were extracted at termination and assessed by means of transmission electron, scanning electron and light microscopy. The extracted fundic and pyloric biopsies revealed asthma alone induced parietal cell hypertrophy (increase in parietal cell size P < 0.000100 in both stomach regions) and chief cell hyper functioning. The use of Hydrocortisone and Modul8TM, as a therapy to correct the perceived gastric alterations were dismal; only in the case of fundic parietal cells were both treatments able to compensate for the hypertrophic effect caused by asthma, while in the pylorus parietal cell asthma- induced hypertrophy was only compensated for by Modul8TM.


La literatura científica, aunque limitada en esta área, apoya la hipótesis de que el asma, por medio del tráfico selectivo de leucocitos entre los diferentes sitios y la mucosa glandular del cuerpo, puede tener los mismos efectos fisiopatológicos en el estómago y las vías respiratorias. Este estudio tuvo como objetivo determinar si el asma, en ausencia y presencia de diversos tratamientos para el asma (hidrocortisona y Modul8 TM), generó alguna alteración morfológica en las céluals parietales y principales del estómago. El modelo murino BALB/c del ratón asmático fue el modelo de elección en este estudio. El protocolo de inducción de asma, así como el tratamiento del asma demostró ser eficaz con la ayuda de lavado bronquial y cuantificación leucocitaria del fluido. Biopsias de las regiones fúndica y pilórica fueron extraídas y evaluadas por medio de microscopía electrónica de transmisión, de barrido y de luz. Las biopsias extraídas de la región fúndica y pilórica revelaron que el asma solamente induce hipertrofia de las células parietales (aumento del tamaño de las células parietales P <0,00001 en ambas regiones del estómago) e hiperfuncionamiento de las células principales. El uso de hidrocortisona y Modul8 TM, como una terapia para corregir las alteraciones gástricas fue disimil, sólo en el caso de las células parietales fúndicas ambos tratamientos fueron capaces de compensar el efecto hipertrófico causado por el asma, mientras que en la célula parietal pílorica la hipertrofia inducida por el asma solamente se vio compensada por Modul8TM.


Assuntos
Animais , Feminino , Ratos , Asma/patologia , Estômago/patologia , Estômago/ultraestrutura , Antiasmáticos , Modelos Animais de Doenças , Fundo Gástrico/patologia , Fundo Gástrico/ultraestrutura , Hipertrofia , Leucócitos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Nebulizadores e Vaporizadores , Células Parietais Gástricas , Piloro/patologia , Piloro/ultraestrutura
19.
Int. j. morphol ; 27(3): 955-963, sept. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-598962

RESUMO

Modul8® is a composite mixture of natural products that are known to be an immunomodulator. In the current study the effect of this immunomodulator is tested on an experimental asthmatic BALB/c mouse model to investigate its properties on the white blood cell count in the blood and bronchial lavage of the animals since white blood cells play a fundamental role in the inflammatory process involved in asthma. As it is known that platelets also play an important role in the immune system, the ultrastructure of platelets and fibrin networks were also investigated by scanning electron microscopy. The animals were sensitised, nebulized and treated over a period of 43 days until termination. Results from the blood smears as well as the bronchial lavage smears revealed significantly higher eosinophil counts in the asthmatic group compared to the control and treated groups. Changes in the ultrastructure of the platelets and fibrin networks could also be observed, with the Modul8® -treated group appearing similar to that of the control group where thick major and thin minor fibres could clearly be distinguished and a tight mass of platelet aggregate could be observed. Whereas the fibrin networks from the asthmatic animals appeared flimsy with a tight mass of thin fibres covering the thick major fibres. The asthmatic platelet aggregates appeared granular without the tight round appearance of the control platelet aggregates. It is therefore concluded that Modul8® positively influences the white blood cell counts by altering the asthmatic profile to look similar to that of the control. Also, it seems as if Modul8® has a stabilizing effect on the platelets and fibrin networks. From these results it can be suggested that Modul8® might successfully be used in the treatment of inflammatory conditions such as asthma.


Modul8® es una mezcla compuesta de productos naturales que es conocida por ser un inmunomodulador. En el presente estudio, el efecto de este inmunomodulador se prueba de forma experimental en el modelo de ratón asmáticos BALB/c, para investigar sus propiedades sobre el conteo de glóbulos blancos en la sangre y lavado bronquial de los animales, ya que los glóbulos blancos desempeñan un papel fundamental en el proceso de respuesta inflamatoria implicado en el asma. Como es sabido, también las plaquetas desempeñan un papel importante en el sistema inmunológico, así, la ultraestructura de las plaquetas y las redes de fibrina también fueron investigadas por microscopía electrónica de barrido. Los animales fueron sensibilizados, nebulizados y tratados durante un período de 43 días hasta el término. Los resultados de los frotis de sangre, así como los de lavado bronquial revelaron un número significativamente mayor de eosinófilos en el grupo de asmáticos en comparación con el control y grupos tratados. Cambios en la ultraestructura de las plaquetas y redes de fibrina también pueden ser observados, donde el grupo tratado con la Modul8® aparece similar a el grupo control, donde los fibras de mayor grosor y menor grosor pueden ser claramente distinguidas y además, puede ser observada una apretada masa de plaquetas aglutinadas. Considerando las redes de la fibrina en animales asmáticos parecen endebles con una apretada masa de fibras de menor grosor que cubren las fibras de mayor grosor. Los agregados de plaquetas en asmáticos aparecen granulares sin el aspecto apretado del agregado plaquetario que rodea al grupo control. Por tanto, se concluye que Modul8® positivamente influye en el conteo de glóbulos blancos mediante la alteración del perfil de asmáticos a un aspecto similar al del control. Además, parece como si Modul8® tuviera un efecto estabilizador en las plaquetas y las redes de fibrina. De estos resultados se puede sugerir que Modul8® puede ser utilizado...


Assuntos
Humanos , Recém-Nascido , Lactente , Asma/diagnóstico , Asma/sangue , Asma/veterinária , Fatores Imunológicos/análise , Fatores Imunológicos/farmacologia , Fatores Imunológicos , Fibrina/ultraestrutura , Plaquetas/ultraestrutura , Camundongos Endogâmicos BALB C/anatomia & histologia , Camundongos Endogâmicos BALB C/sangue
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