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1.
Am J Physiol Cell Physiol ; 326(4): C1226-C1236, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406827

RESUMO

Cancer and chemotherapy induce a severe loss of muscle mass (known as cachexia), which negatively impact cancer treatment and patient survival. The aim of the present study was to investigate whether cannabidiol (CBD) administration may potentially antagonize the effects of cisplatin in inducing muscle atrophy, using a model of myotubes in culture. Cisplatin treatment resulted in a reduction of myotube diameter (15.7 ± 0.3 vs. 22.2 ± 0.5 µm, P < 0.01) that was restored to control level with 5 µM CBD (20.1 ± 0.4 µM, P < 0.01). Protein homeostasis was severely altered with a ≈70% reduction in protein synthesis (P < 0.01) and a twofold increase in proteolysis (P < 0.05) in response to cisplatin. Both parameters were dose dependently restored by CBD cotreatment. Cisplatin treatment was associated with increased thiobarbituric acid reactive substances (TBARS) content (0.21 ± 0.03 to 0.48 ± 0.03 nmol/mg prot, P < 0.05), catalase activity (0.24 ± 0.01 vs. 0.13 ± 0.02 nmol/min/µg prot, P < 0.01), whereas CBD cotreatment normalized TBARS content to control values (0.22 ± 0.01 nmol/mg prot, P < 0.01) and reduced catalase activity (0.17 ± 0.01 nmol/min/µg prot, P < 0.05). These changes were associated with increased mRNA expression of GPX1, SOD1, SOD2, and CAT mRNA expression in response to cisplatin (P < 0.01), which was corrected by CBD cotreatment (P < 0.05). Finally, cisplatin treatment increased the mitochondrial protein content of NDUFB8, UQCRC2, COX4, and VDAC1 (involved in mitochondrial respiration and apoptosis), and CBD cotreatment restored their expression to control values. Altogether, our results demonstrated that CBD antagonize the cisplatin-induced C2C12 myotube atrophy and could be used as an adjuvant in the treatment of cancer cachexia to help maintain muscle mass and improve patient quality of life.NEW & NOTEWORTHY In an in vitro model, cisplatin treatment led to myotube atrophy associated with dysregulation of protein homeostasis and increased oxidative stress, resulting in increased apoptosis. Cotreatment with cannabidiol was able to prevent this phenotype by promoting protein homeostasis and reducing oxidative stress.


Assuntos
Canabidiol , Neoplasias , Humanos , Cisplatino/toxicidade , Canabidiol/farmacologia , Canabidiol/metabolismo , Canabidiol/uso terapêutico , Caquexia/metabolismo , Catalase/metabolismo , Qualidade de Vida , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/farmacologia , Fibras Musculares Esqueléticas/metabolismo , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/prevenção & controle , Atrofia Muscular/tratamento farmacológico , Estresse Oxidativo , Neoplasias/metabolismo , RNA Mensageiro/metabolismo
2.
PLoS Biol ; 18(12): e3000948, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33284790

RESUMO

Chronic inflammation is now a well-known precursor for cancer development. Infectious prostatitis are the most common causes of prostate inflammation, but emerging evidence points the role of metabolic disorders as a potential source of cancer-related inflammation. Although the widely used treatment for prostate cancer based on androgen deprivation therapy (ADT) effectively decreases tumor size, it also causes profound alterations in immune tumor microenvironment within the prostate. Here, we demonstrate that prostates of a mouse model invalidated for nuclear receptors liver X receptors (LXRs), crucial lipid metabolism and inflammation integrators, respond in an unexpected way to androgen deprivation. Indeed, we observed profound alterations in immune cells composition, which was associated with chronic inflammation of the prostate. This was explained by the recruitment of phagocytosis-deficient macrophages leading to aberrant hyporesponse to castration. This phenotypic alteration was sufficient to allow prostatic neoplasia. Altogether, these data suggest that ADT and inflammation resulting from metabolic alterations interact to promote aberrant proliferation of epithelial prostate cells and development of neoplasia. This raises the question of the benefit of ADT for patients with metabolic disorders.


Assuntos
Imunidade/fisiologia , Receptores X do Fígado/metabolismo , Próstata/metabolismo , Antagonistas de Androgênios/imunologia , Androgênios/metabolismo , Animais , Modelos Animais de Doenças , Imunidade/imunologia , Receptores X do Fígado/genética , Receptores X do Fígado/imunologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Neoplasias/etiologia , Neoplasias/imunologia , Neoplasias/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Receptores Citoplasmáticos e Nucleares/metabolismo , Microambiente Tumoral
3.
Exp Eye Res ; 165: 99-104, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28958587

RESUMO

Oxidative stress (OS) associated with direct contact with the environment and light exposure is a very potent and continuous stressor of the ocular surface and internal structures of the eye that are required to manage its effects. Constant replenishment of tears together with the superficial lipid layer produced by the meibomian glands (MG) is one protective mechanism. The lipid-rich fraction of the tears coats the deeper aqueous fraction, preventing its evaporation. However, lipids are particularly sensitive to oxidative damage that could alter tear film quality. To counteract oxidative damage, MG along with other structures of the ocular surface use primary antioxidant (AO) systems to limit OS damage such as lipid peroxidation. Limited information concerning the primary enzymatic AO system of the human MG prompted this investigation. Using different approaches (RT-PCR, enzymatic activity assays and immuno-fluorescent microscopy), we determined the presence, distribution and subcellular locations of the major AO enzymes belonging to the classical catalytic triad (superoxide dismutase, catalase and glutathione peroxidases) in adult human MG and conjunctiva (Conj). We showed that both tissues exhibit glutathione peroxidase expression. In addition to the ubiquitous cytosolic GPx1 protein, there was significant expression of GPx2, GPx4 and GPx7. These isoforms are known to preferentially scavenge phospholipid-hydroperoxide compounds. This characterization of the primary AO system of human MG and Conj may help pave the way for the development of diagnostic procedures and have implications for treatment of common MG dysfunction (MGD) and dry eye syndrome (DES).


Assuntos
Catalase/metabolismo , Túnica Conjuntiva/metabolismo , Glutationa Peroxidase/metabolismo , Glândulas Tarsais/metabolismo , Superóxido Dismutase/metabolismo , Citosol/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia
4.
Biol Reprod ; 94(3): 55, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26792941

RESUMO

After its production in the testis, a spermatozoon has to undergo posttesticular maturation steps to become fully motile and fertile. The first step is epididymal maturation, during which immature spermatozoa are transformed into biochemically mature cells ready to proceed to the next step, capacitation, a physiological process occurring in the female genital tract. The biochemical transformations include modification of sperm lipid composition during epididymal transit, with significant changes in fatty acids, phospholipids, and sterols between the caput and the cauda epididymal spermatozoa. Although quantitative aspects of these changes are well documented for several mammalian species, molecular mechanisms governing these steps are poorly understood. Transgenic male mice invalidated for the two liver X receptors (LXRalpha and LXRbeta, nuclear oxysterol receptors regulating cholesterol and lipid metabolism) become sterile when aging, showing an epididymal phenotype. We used single-knockout-model mice to characterize the role of each LXR isoform during sperm maturation in the epididymis. We show here that although a certain redundancy exists in the functions of the two LXR isoforms, some physiological processes are more under the influence of only one of them. In both cases, aging males showed slight subfertility, associated with dyslipidemia, emphasizing the importance of lipid metabolism in relation with male fertility.


Assuntos
Epididimo/metabolismo , Regulação da Expressão Gênica/fisiologia , Receptores X do Fígado/metabolismo , Envelhecimento , Animais , Colesterol/metabolismo , Epididimo/patologia , Feminino , Homeostase , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Metabolismo dos Lipídeos , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Knockout , Gravidez , Taxa de Gravidez , Isoformas de Proteínas
5.
Cancers (Basel) ; 16(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38893271

RESUMO

Epidemiological studies point to cholesterol as a possible key factor for both prostate cancer incidence and progression. It could represent a targetable metabolite as the most aggressive tumors also appear to be sensitive to therapies designed to decrease hypercholesterolemia, such as statins. However, it remains unknown whether and how cholesterol, through its dietary uptake and its metabolism, could be important for early tumorigenesis. Oncogene clonal induction in the Drosophila melanogaster accessory gland allows us to reproduce tumorigenesis from initiation to early progression, where tumor cells undergo basal extrusion to form extra-epithelial tumors. Here we show that these tumors accumulate lipids, and especially esterified cholesterol, as in human late carcinogenesis. Interestingly, a high-cholesterol diet has a limited effect on accessory gland tumorigenesis. On the contrary, cell-specific downregulation of cholesterol uptake, intracellular transport, or metabolic response impairs the formation of such tumors. Furthermore, in this context, a high-cholesterol diet suppresses this impairment. Interestingly, expression data from primary prostate cancer tissues indicate an early signature of redirection from cholesterol de novo synthesis to uptake. Taken together, these results reveal that during early tumorigenesis, tumor cells strongly increase their uptake and use of dietary cholesterol to specifically promote the step of basal extrusion. Hence, these results suggest the mechanism by which a reduction in dietary cholesterol could lower the risk and slow down the progression of prostate cancer.

6.
Elife ; 122023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37310207

RESUMO

Long considered an accessory tubule of the male reproductive system, the epididymis is proving to be a key determinant of male fertility. In addition to its secretory role in ensuring functional maturation and survival of spermatozoa, the epididymis has a complex immune function. Indeed, it must manage both peripheral tolerance to sperm antigens foreign to the immune system and the protection of spermatozoa as well as the organ itself against pathogens ascending the epididymal tubule. Although our knowledge of the immunobiology of this organ is beginning to accumulate at the molecular and cellular levels, the organization of blood and lymphatic networks of this tissue, important players in the immune response, remains largely unknown. In the present report, we have taken advantage of a VEGFR3:YFP transgenic mouse model. Using high-resolution three-dimensional (3D) imaging and organ clearing coupled with multiplex immunodetections of lymphatic (LYVE1, PDPN, PROX1) and/or blood (PLVAP/Meca32) markers, we provide a simultaneous deep 3D view of the lymphatic and blood epididymal vasculature in the mature adult mouse as well as during postnatal development.


Assuntos
Epididimo , Imageamento Tridimensional , Masculino , Animais , Camundongos , Sêmen , Espermatozoides , Camundongos Transgênicos
7.
Oncogene ; 42(38): 2854-2867, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37587334

RESUMO

Increasing evidence points towards a causal link between exposure to persistent organic pollutants (POPs) with increased incidence and aggressivity of various cancers. Among these POPs, dioxin and PCB-153 are widely found in our environment and represent a significant source of contamination. Dioxin exposure has already been linked to cancer such as non-Hodgkin's lymphoma, but remains to be more extensively investigated in other cancers. Potential implications of dioxin and PCB-153 in prostate cancer progression spurred us to challenge both ex vivo and in vivo models with low doses of these POPs. We found that dioxin or PCB-153 exposure increased hallmarks of growth and metastasis of prostate cancer cells ex vivo and in grafted NOD-SCID mice. Exposure induced histopathological carcinoma-like patterns in the Ptenpc-/- mice. We identified up-regulation of Acetyl-CoA Acetyltransferase-1 (ACAT1) involved in ketone bodies pathway as a potential target. Mechanistically, genetic inhibition confirmed that ACAT1 mediated dioxin effect on cell migration. Using public prostate cancer datasets, we confirmed the deregulation of ACAT1 and associated gene encoded ketone bodies pathway enzymes such as OXCT1, BDH1 and HMGCL in advanced prostate cancer. To further explore this link between dioxin and ACAT1 deregulation, we analyzed a unique prostate-tumour tissue collection from the USA veterans exposed to agent orange, known to be highly contaminated by dioxin because of industrial production. We found that ACAT1 histoscore is significantly increased in exposed patients. Our studies reveal the implication of dioxin and PCB-153 to induce a prometastatic programme in prostate tumours and identify ACAT1 deregulation as a key event in this process.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Poluentes Orgânicos Persistentes , Dioxinas/toxicidade , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Acetiltransferases
8.
J Biol Chem ; 286(10): 8030-8042, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21189261

RESUMO

Indoleamine 2,3-dioxygenase (IDO) is the first and rate-limiting enzyme of tryptophan catabolism through the kynurenine pathway. Intriguingly, IDO is constitutively and highly expressed in the mammalian epididymis in contrast to most other tissues where IDO is induced by proinflammatory cytokines, such as interferons. To gain insight into the role of IDO in the physiology of the mammalian epididymis, we studied both wild type and Ido1(-/-)-deficient mice. In the caput epididymis of Ido1(-/-) animals, the lack of IDO activity was not compensated by other tryptophan-catabolizing enzymes and led to the loss of kynurenine production. The absence of IDO generated an inflammatory state in the caput epididymis as revealed by an increased accumulation of various inflammation markers. The absence of IDO also increased the tryptophan content of the caput epididymis and generated a parallel increase in caput epididymal protein content as a consequence of deficient proteasomal activity. Surprisingly, the lack of IDO expression had no noticeable impact on overall male fertility but did induce highly significant increases in both the number and the percentage of abnormal spermatozoa. These changes coincided with a significant decrease in white blood cell count in epididymal fluid compared with wild type mice. These data provide support for IDO playing a hitherto unsuspected role in sperm quality control in the epididymis involving the ubiquitination of defective spermatozoa and their subsequent removal.


Assuntos
Epididimo/enzimologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/biossíntese , Espermatozoides/enzimologia , Triptofano/metabolismo , Ubiquitinação , Animais , Epididimo/patologia , Regulação Enzimológica da Expressão Gênica , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Infertilidade Masculina/enzimologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Inflamação/enzimologia , Inflamação/genética , Inflamação/patologia , Cinurenina/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Especificidade de Órgãos , Espermatozoides/patologia , Triptofano/genética
9.
Med Sci (Paris) ; 28(5): 519-25, 2012 May.
Artigo em Francês | MEDLINE | ID: mdl-22643006

RESUMO

Spermatozoa leave the testis in an immature functional state and are devoid of self defense mechanisms. They will become motile and ready to fertilize only after their descent and their progressive maturation within the epididymal tubule. The epididymis also ensures the survival and the protection of male gametes while they go through the epididymis and during their storage in between two ejaculations. Amongst common stresses that concern spermatozoa, oxidative stress occupies a peculiar and dual position. While the events of epididymal sperm maturation necessitate a given level of oxidation, spermatozoa are particularly sensitive to oxidative damage. A fine balance between beneficial oxidation versus detrimental oxidative damage has to be maintained in the epididymal environment. Antioxidant enzymes of the glutathione peroxidase family play a key role in controling such a situation in the epididymis.


Assuntos
Citoproteção/fisiologia , Epididimo/fisiologia , Estresse Oxidativo/fisiologia , Espermatozoides/metabolismo , Animais , Epididimo/citologia , Epididimo/metabolismo , Células Germinativas/metabolismo , Humanos , Masculino , Modelos Biológicos , Espermatogênese/fisiologia , Espermatozoides/citologia , Testículo/metabolismo
10.
Parasitol Int ; 87: 102518, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34808329

RESUMO

Microsporidia are obligate intracellular pathogens capable of infecting a wide variety of hosts ranging from invertebrates to vertebrates. The infection process requires a step of prior adherence of Microsporidia to the surface of host cells. A few studies demonstrated the involvement of proteins containing a ricin-B lectin (RBL) domain in parasite infection. In this study Anncalia algerae and Encephalitozoon cuniculi genomes were screened by bioinformatic analysis to identify proteins with an extracellular prediction and possessing RBL-type carbohydrate-binding domains, being both potentially relevant factors contributing to host cell adherence. Three proteins named AaRBLL-1 and AaRBLL-2 from A. algerae and EcRBLL-1 from E. cuniculi, were selected and comparative analysis of sequences suggested their belonging to a multigenic family, with a conserved structural RBL domain despite a significant amino acid sequence divergence. The production of recombinant proteins and antibodies against the three proteins allowed their subcellular localization on the spore wall and/or the polar tube. Adherence inhibition assays based on pre-treatments with recombinant proteins or antibodies highlighted the significant decrease of the proliferation of both E. cuniculi and A. algerae, strongly suggesting that these proteins are involved in the infection process.


Assuntos
Encephalitozoon cuniculi/química , Proteínas Fúngicas/fisiologia , Microsporídios/química , Ricina/metabolismo , Animais , Linhagem Celular , Biologia Computacional , Cães , Encephalitozoon cuniculi/genética , Encephalitozoon cuniculi/imunologia , Humanos , Células Madin Darby de Rim Canino , Microsporídios/genética , Microsporídios/imunologia , Coelhos , Proteínas Recombinantes/genética , Esporos Fúngicos/imunologia , Esporos Fúngicos/isolamento & purificação
11.
Dev Dyn ; 239(12): 3324-35, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20941779

RESUMO

The testis-determining gene SRY is not well-conserved among mammals, and particularly between mouse and other mammals. To evaluate SRY function in a nonrodent species, we produced an antibody against goat SRY and used it to investigate the expression pattern of SRY throughout goat testicular development. By contrast with the mouse, SRY is primarily expressed in most cells of XY genital-ridges and not solely in pre-Sertoli cells. Between cord formation and prepuberty, SRY remains expressed in both Sertoli and germinal cells. During adulthood, SRY expression declines and then disappears from meiotic germ cells, only remaining present at low levels in some spermatogonia. Unlike the germinal lineage, SRY continues to be highly expressed in adult Sertoli cells with a typical nuclear staining. Our data indicate that in goat, the role of SRY may not be limited to testis determination and could have other functions in testicular maintenance and hence male fertility.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteína da Região Y Determinante do Sexo/metabolismo , Animais , Western Blotting , Células COS , Chlorocebus aethiops , Feminino , Cabras , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Diferenciação Sexual/genética , Diferenciação Sexual/fisiologia , Proteína da Região Y Determinante do Sexo/genética , Espermatogônias/citologia , Espermatogônias/metabolismo , Testículo/embriologia
12.
Methods Mol Biol ; 2198: 255-268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32822037

RESUMO

Male infertility is associated with several causes affecting the paternal nucleus such as DNA lesions (breaks, deletions, mutations, ...) or numerical chromosome anomalies. More recently, male infertility has also been associated with changes in the sperm epigenome, including modification in the topology of chromatin (Olszewska et al., Chromosome Research 16:875-890, 2008; Alladin et al., Syst Biol Reprod Med 59: 146-152, 2013) ref with number 1, 2. Indeed, the positioning of chromosomes in the sperm nucleus is nonrandom and defines chromosome territories (Champroux et al., Genes (Basel) 9:501, 2018) ref with number 3 whose optimal organization determines the success of embryonic development. In this context, the study of the spatial distribution of chromosomes in sperm cells could be relevant for clinical diagnosis. We describe here a in situ fluorescence hybridization (FISH) strategy coupled with a fluorescent immunocytochemistry approach followed by confocal analysis and reconstruction (2D/3D) as a powerful tool to analyze the location of chromosomes in the sperm nucleus using the mouse sperm as a model. Already, the two-dimensional (2D) analysis of FISH and immunofluorescence data reveal the location of chromosomes as well as the different markings on the spermatic nucleus. In addition, a good 3D rendering after Imaris software processing was obtained when Z-stacks of images were acquired over a defined volume (10 µm × 13 µm × 15 µm) with a sequential scanning mode to minimize bleed-through effects and avoid overlapping wavelengths.


Assuntos
Posicionamento Cromossômico/imunologia , Microscopia Confocal/métodos , Espermatozoides/imunologia , Aneuploidia , Animais , Núcleo Celular/imunologia , Cromatina , Aberrações Cromossômicas , Posicionamento Cromossômico/genética , Cromossomos/imunologia , Modelos Animais de Doenças , Imunofluorescência/métodos , Hibridização in Situ Fluorescente/métodos , Infertilidade Masculina/imunologia , Masculino , Camundongos , Espermatozoides/citologia
13.
Br J Pharmacol ; 178(16): 3277-3293, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33080050

RESUMO

Liver X receptors (LXRs) are members of the nuclear receptor superfamily that are canonically activated by oxidized derivatives of cholesterol. Since the mid-90s, numerous groups have identified LXRs as endocrine receptors that are involved in the regulation of various physiological functions. As a result, when their expression is genetically modified in mice, phenotypic analyses reveal endocrine disorders ranging from infertility to diabetes and obesity, nervous system pathologies such Alzheimer's or Parkinson's disease, immunological disturbances, inflammatory response, and enhancement of tumour development. Based on such findings, it appears that LXRs could constitute good pharmacological targets to prevent and/or to treat these diseases. This review discusses the various aspects of LXR drug discovery, from the tools available for the screening of potential LXR modulators to the current situational analysis of the drugs in development. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.


Assuntos
Diabetes Mellitus , Doença de Parkinson , Animais , Colesterol , Receptores X do Fígado , Camundongos , Receptores Citoplasmáticos e Nucleares
14.
Commun Biol ; 4(1): 691, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099857

RESUMO

Chromatin of male and female gametes undergoes a number of reprogramming events during the transition from germ cell to embryonic developmental programs. Although the rearrangement of DNA methylation patterns occurring in the zygote has been extensively characterized, little is known about the dynamics of DNA modifications during spermatid maturation. Here, we demonstrate that the dynamics of 5-carboxylcytosine (5caC) correlate with active transcription of LINE-1 retroelements during murine spermiogenesis. We show that the open reading frames of active and evolutionary young LINE-1s are 5caC-enriched in round spermatids and 5caC is eliminated from LINE-1s and spermiogenesis-specific genes during spermatid maturation, being simultaneously retained at promoters and introns of developmental genes. Our results reveal an association of 5caC with activity of LINE-1 retrotransposons suggesting a potential direct role for this DNA modification in fine regulation of their transcription.


Assuntos
Citosina/análogos & derivados , Elementos Nucleotídeos Longos e Dispersos , Fases de Leitura Aberta , Espermátides/metabolismo , Animais , Citosina/metabolismo , Masculino , Camundongos , Espermátides/citologia , Espermatogênese , Transcrição Gênica
15.
Hum Mol Genet ; 17(7): 1010-9, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18158309

RESUMO

Polyalanine (polyAla) tract expansions have been associated with an increasing number of human diseases. Here, we have undertaken a functional study of the effects of polyAla expansions in the context of the transcription factor FOXL2, involved in cranio-facial and ovarian development. Using two cellular models, we show that FOXL2 polyAla expansions lead to protein mislocalization and aggregation in a length-dependent manner. The fraction of cells containing cytoplasmic staining displays a sigmoidal relationship with respect to the length of the polyAla tract, suggesting the existence of a threshold length above which protein mislocalization occurs. The existence of such a threshold might be rationalized if we consider that the longer the polyAla tract is, the higher its tendency to misfolding or to inducing spurious interactions with cytoplasmic components. To study the intranuclear dynamics of polyAla-expanded FOXL2, we performed fluorescence recovery after photobleaching experiments. The most unexpected result concerned the pathogenic protein containing 19 Ala residues in the run, which was virtually immobile, although this variant does not present a classical aggregation pattern. Luciferase assays and real time RT-PCR of many potential target genes showed that polyAla expansions induce different losses of activity according to the target promoters tested. We provide molecular explanations for these findings. Although our main focus is the mechanisms of pathogenesis of polyAla-expanded proteins, we discuss the potential relevance of polyAla length variation in micro- and macroevolution because polyAla-containing proteins tend to be transcription factors.


Assuntos
Anormalidades Craniofaciais/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Ovário/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Expansão das Repetições de Trinucleotídeos , Animais , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Citoplasma/química , Citoplasma/metabolismo , Feminino , Recuperação de Fluorescência Após Fotodegradação , Proteína Forkhead Box L2 , Fatores de Transcrição Forkhead/química , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/metabolismo , Humanos , Espaço Intranuclear/metabolismo , Microscopia de Fluorescência , Ovário/anormalidades , Ovário/embriologia , Peptídeos/metabolismo , Transporte Proteico , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/análise , Transfecção
16.
J Agric Food Chem ; 68(52): 15409-15417, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33337882

RESUMO

Plant defense inducers (PDIs) are booming and attractive protection agents designed to immunostimulate the plant to reduce subsequent pathogen colonization. The structure-PDI activity relationships of four flavan-3-ols: Epicatechin (EC), Epigallocatechin (EGC), Epicatechin gallate (ECG), Epigallocatechin gallate (EGCG) and Gallotannic acid (GTA) were investigated in both whole plant and suspension cell systems. ECG, EGCG, and GTA displayed elicitor activities. Their infiltration into tobacco leaves induced hypersensitive reaction-like lesions with topical scopoletin and PR-target transcript accumulations. On the contrary, EC and EGC infiltrations fail to trigger the biochemical changes in tobacco tissues. The tobacco BY-2 cells challenged with ECG, EGCG, or GTA led to alkalinization of the BY-2 extracellular medium while EC and EGC did not trigger any pH variation. This work provides evidence that the esterified gallate pattern is as an essential flavonoid entity to induce plant defense reactions in tobacco. The phytoprotective properties of the esterified gallate-free EC and the esterified gallate-rich GTA were evaluated on the tobacco/Phytophthora parasitica var. nicotianae (Ppn) pathosystem. Tobacco treatment with EC did not induce significant protection against Ppn compared to GTA which shows antimicrobial properties on Ppn and decreases the infection on GTA-infiltrated and -sprayed wild-type leaves. GTA protection was impaired in the transgenic NahG tobacco plants, suggesting that protection was mediated by salicylic acid.


Assuntos
Flavonoides/química , Flavonoides/farmacologia , Nicotiana/efeitos dos fármacos , Doenças das Plantas/imunologia , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Estrutura Molecular , Phytophthora/fisiologia , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/imunologia , Folhas de Planta/microbiologia , Nicotiana/imunologia , Nicotiana/microbiologia
17.
Asian J Androl ; 22(6): 590-601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32270769

RESUMO

The mammalian epididymis not only plays a fundamental role in the maturation of spermatozoa, but also provides protection against various stressors. The foremost among these is the threat posed by oxidative stress, which arises from an imbalance in reactive oxygen species and can elicit damage to cellular lipids, proteins, and nucleic acids. In mice, the risk of oxidative damage to spermatozoa is mitigated through the expression and secretion of glutathione peroxidase 5 (GPX5) as a major luminal scavenger in the proximal caput epididymidal segment. Accordingly, the loss of GPX5-mediated protection leads to impaired DNA integrity in the spermatozoa of aged Gpx5-/- mice. To explore the underlying mechanism, we have conducted transcriptomic analysis of caput epididymidal epithelial cells from aged (13 months old) Gpx5-/- mice. This analysis revealed the dysregulation of several thousand epididymal mRNA transcripts, including the downregulation of a subgroup of piRNA pathway genes, in aged Gpx5-/- mice. In agreement with these findings, we also observed the loss of piRNAs, which potentially bind to the P-element-induced wimpy testis (PIWI)-like proteins PIWIL1 and PIWIL2. The absence of these piRNAs was correlated with the elevated mRNA levels of their putative gene targets in the caput epididymidis of Gpx5-/- mice. Importantly, the oxidative stress response genes tend to have more targeting piRNAs, and many of them were among the top increased genes upon the loss of GPX5. Taken together, our findings suggest the existence of a previously uncharacterized somatic piRNA pathway in the mammalian epididymis and its possible involvement in the aging and oxidative stress-mediated responses.


Assuntos
Epididimo/metabolismo , Glutationa Peroxidase/fisiologia , RNA Interferente Pequeno/metabolismo , Envelhecimento/metabolismo , Animais , Regulação para Baixo , Epididimo/enzimologia , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Glutationa Peroxidase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Mol Hum Reprod ; 15(4): 205-13, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19218284

RESUMO

One of the major decisions that germ cells make during their development is whether to differentiate into oocytes or sperm. In mice, the germ cells' decision to develop as male or female depends on sex-determining signalling molecules in the embryonic gonadal environment rather than the sex chromosome constitution of the germ cells themselves. In response to these sex-determining cues, germ cells in female embryos initiate oogenesis and enter meiosis, whereas germ cells in male embryos initiate spermatogenesis and inhibit meiosis until after birth. However, it is not clear whether the signalling molecules that mediate germ cell sex determination act in the developing testis or the developing ovary, or what these signalling molecules might be. Here, we review the evidence for the existence of meiosis-inducing and meiosis-preventing substances in the developing gonad, and more recent studies aimed at identifying these molecules in mice. In addition, we discuss the possibility that some of the reported effects of these factors on germ cell development may be indirect consequences of impairing sexual differentiation of gonadal somatic cells or germ cell survival. Understanding the molecular mechanisms of germ cell sex determination may provide candidate genes for susceptibility to germ cell tumours and infertility in humans.


Assuntos
Células Germinativas/fisiologia , Mamíferos/fisiologia , Processos de Determinação Sexual , Aneuploidia , Animais , Linhagem da Célula/genética , Fertilidade/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Gônadas/citologia , Gônadas/embriologia , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Humanos , Neoplasias/fisiopatologia , Diferenciação Sexual/genética , Diferenciação Sexual/fisiologia , Transdução de Sinais/fisiologia
19.
BMC Dev Biol ; 8: 36, 2008 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-18384673

RESUMO

BACKGROUND: Up to now, two loci have been involved in XX sex-reversal in mammals following loss-of-function mutations, PIS (Polled Intersex Syndrome) in goats and R-spondin1 (RSPO1) in humans. Here, we analyze the possible interaction between these two factors during goat gonad development. Furthermore, since functional redundancy between different R-spondins may influence gonad development, we also studied the expression patterns of RSPO2, 3 and 4. RESULTS: Similarly to the mouse, RSPO1 shows a sex-dimorphic expression pattern during goat gonad development with higher levels in the ovaries. Interestingly, the PIS mutation does not seem to influence its level of expression. Moreover, using an RSPO1 specific antibody, the RSPO1 protein was localized in the cortical area of early differentiating ovaries (36 and 40 dpc). This cortical area contains the majority of germ cell that are surrounded by FOXL2 negative somatic cells. At latter stages (50 and 60 dpc) RSPO1 protein remains specifically localized on the germ cell membranes. Interestingly, a time-specific relocation of RSPO1 on the germ cell membrane was noticed, moving from a uniform distribution at 40 dpc to a punctuated staining before and during meiosis (50 and 60 dpc respectively). Interestingly, also RSPO2 and RSPO4 show a sex-dimorphic expression pattern with higher levels in the ovaries. Although RSPO4 was found to be faintly and belatedly expressed, the expression of RSPO2 increases at the crucial 36 dpc stage, as does that of FOXL2. Importantly, RSPO2 expression appears dramatically decreased in XX PIS-/- gonads at all three tested stages (36, 40 and 50 dpc). CONCLUSION: During goat ovarian development, the pattern of expression of RSPO1 is in agreement with its possible anti-testis function but is not influenced by the PIS mutation. Moreover, our data suggest that RSPO1 may be associated with germ cell development and meiosis. Interestingly, another RSPO gene, RSPO2 shows a sex-dimorphic pattern of expression that is dramatically influenced by the PIS mutation.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento , Cabras/genética , Ovário/embriologia , Diferenciação Sexual/genética , Trombospondinas/genética , Animais , DNA Complementar , Transtornos do Desenvolvimento Sexual , Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Feminino , Cabras/embriologia , Cabras/fisiologia , Fases de Leitura Aberta , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Front Cell Dev Biol ; 6: 50, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868581

RESUMO

The past decade has seen a tremendous increase in interest and progress in the field of sperm epigenetics. Studies have shown that chromatin regulation during male germline development is multiple and complex, and that the spermatozoon possesses a unique epigenome. Its DNA methylation profile, DNA-associated proteins, nucleo-protamine distribution pattern and non-coding RNA set up a unique epigenetic landscape which is delivered, along with its haploid genome, to the oocyte upon fertilization, and therefore can contribute to embryogenesis and to the offspring health. An emerging body of compelling data demonstrates that environmental exposures and paternal lifestyle can change the sperm epigenome and, consequently, may affect both the embryonic developmental program and the health of future generations. This short review will attempt to provide an overview of what is currently known about sperm epigenome and the existence of transgenerational epigenetic inheritance of paternally acquired traits that may contribute to the offspring phenotype.

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