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1.
Hum Reprod ; 39(3): 504-508, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38224259

RESUMO

Genetic causes account for 10-15% of male factor infertility, making the genetic investigation an essential and useful tool, mainly in azoospermic and severely oligozoospermic men. In these patients, the most frequent findings are chromosomal abnormalities and Y chromosome long arm microdeletions, which cause a primary severe spermatogenic impairment with classically increased levels of FSH. On the other hand, polymorphisms in the FSH receptor (FSHR) and FSH beta chain (FSHB) genes have been associated with different FSH plasma levels, due to variations in the receptor sensitivity (FSHR) or in the production of FSH from the pituitary gland (FSHB). Here, we describe an unusual patient with a combined genetic alteration (classic AZFc deletion of the Y chromosome and TT homozygosity for the -211G>T polymorphism in the FSHB gene (rs10835638)), presenting with cryptozoospermia, severe hypospermatogenesis, and normal LH and testosterone plasma concentrations, but low FSH levels. The patient partially benefitted from treatment with FSH (150 IU three times/week for 6 months) which allowed him to cryopreserve enough motile spermatozoa to be used for intracytoplasmic sperm injection. According to our knowledge, this is the first report of an infertile man with AZFc microdeletion with low FSH plasma concentrations related to homozygosity for the -211G>T polymorphism in the FSHB gene.


Assuntos
Deleção Cromossômica , Infertilidade Masculina , Oligospermia , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Sêmen , Infertilidade Masculina/genética , Subunidade beta do Hormônio Folículoestimulante/genética , Oligospermia/genética , Cromossomos Humanos Y/genética
2.
Int J Mol Sci ; 24(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38069064

RESUMO

Obesity is a systemic disease frequently associated with important complications such as type 2 diabetes and cardiovascular diseases. It has also been proven that obesity is a disease associated with chronic low-grade systemic inflammation and that weight loss improves this low-grade chronic inflammatory condition. The P2X7 purinergic receptor (P2X7R), belonging to the family of the receptors for extracellular ATP, is a main player in inflammation, activating inflammasome and pro-inflammatory cytokine production. In this study, we evaluated the plasma levels of soluble P2X7R (sP2X7R) measured in a group of obese patients before and one year after bariatric surgery. Furthermore, we evaluated the relation of sP2X7R to inflammatory marker plasma levels. We enrolled 15 obese patients who underwent laparoscopic sleeve gastrectomy, evaluating anthropometric parameters (weight, height, BMI and waist circumference) before and after surgery. Moreover, we measured the plasma levels of inflammatory markers (CRP, TNFα and IL-6) before and after weight loss via bariatric surgery. The results of our study show that one year after bariatric surgery, obese patients significantly decrease body weight with a significant decrease in CRP, TNF-alfa and IL-6 plasma levels. Similarly, after weight loss, obese subjects showed a significant reduction in sP2X7R plasma levels. Moreover, before surgery, plasma levels of sP2X7R were inversely related with those of CRP, TNF-alfa and IL-6. Given the role of P2X7R in inflammation, we hypothesized that, in obese subjects, sP2X7R could represent a possible marker of chronic low-grade inflammation, hypothesizing a possible role as a mediator of obesity complications.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Obesidade Mórbida , Humanos , Receptores Purinérgicos P2X7 , Diabetes Mellitus Tipo 2/complicações , Interleucina-6 , Obesidade/cirurgia , Obesidade/complicações , Cirurgia Bariátrica/métodos , Inflamação/complicações , Redução de Peso
3.
J Enzyme Inhib Med Chem ; 35(1): 96-108, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31690133

RESUMO

A series of analogues of Amb639752, a novel diacylglycerol kinase (DGK) inhibitor recently discovered by us via virtual screening, have been tested. The compounds were evaluated as DGK inhibitors on α, θ, and ζ isoforms, and as antagonists on serotonin receptors. From these assays emerged two novel compounds, namely 11 and 20, which with an IC50 respectively of 1.6 and 1.8 µM are the most potent inhibitors of DGKα discovered to date. Both compounds demonstrated the ability to restore apoptosis in a cellular model of X-linked lymphoproliferative disease as well as the capacity to reduce the migration of cancer cells, suggesting their potential utility in preventing metastasis. Finally, relying on experimental biological data, molecular modelling studies allow us to set a three-point pharmacophore model for DGK inhibitors.


Assuntos
Indóis/farmacologia , Lipase Lipoproteica/antagonistas & inibidores , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Indóis/síntese química , Indóis/química , Lipase Lipoproteica/metabolismo , Linfócitos/efeitos dos fármacos , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Monócitos/efeitos dos fármacos , Piperazinas/síntese química , Piperazinas/química , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos
5.
Int J Mol Sci ; 20(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682769

RESUMO

Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.


Assuntos
Aterosclerose/metabolismo , Endotélio Vascular/metabolismo , Grelina/genética , Animais , Aorta/metabolismo , Aterosclerose/etiologia , Aterosclerose/genética , Dieta Hiperlipídica/efeitos adversos , Grelina/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Óxido Nítrico Sintase Tipo III , Estresse Oxidativo , Regulação para Cima
6.
Stem Cells ; 35(7): 1733-1746, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28436144

RESUMO

Muscle regeneration depends on satellite cells (SCs), quiescent precursors that, in consequence of injury or in pathological states such as muscular dystrophies, activate, proliferate, and differentiate to repair the damaged tissue. A subset of SCs undergoes self-renewal, thus preserving the SC pool and its regenerative potential. Unacylated ghrelin (UnAG) is a circulating hormone that protects muscle from atrophy, promotes myoblast differentiation, and enhances ischemia-induced muscle regeneration. Here we show that UnAG increases SC activity and stimulates Par polarity complex/p38-mediated asymmetric division, fostering both SC self-renewal and myoblast differentiation. Because of those activities on different steps of muscle regeneration, we hypothesized a beneficial effect of UnAG in mdx dystrophic mice, in which the absence of dystrophin leads to chronic muscle degeneration, defective muscle regeneration, fibrosis, and, at later stages of the pathology, SC pool exhaustion. Upregulation of UnAG levels in mdx mice reduces muscle degeneration, improves muscle function, and increases dystrophin-null SC self-renewal, maintaining the SC pool. Our results suggest that UnAG has significant therapeutic potential for preserving the muscles in dystrophies. Stem Cells 2017;35:1733-1746.


Assuntos
Distrofina/genética , Grelina/genética , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/metabolismo , Regeneração/genética , Células Satélites de Músculo Esquelético/metabolismo , Acilação , Animais , Contagem de Células , Diferenciação Celular , Distrofina/metabolismo , Fibrose , Regulação da Expressão Gênica , Grelina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Músculo Esquelético/patologia , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/patologia , Fenótipo , Células Satélites de Músculo Esquelético/patologia , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
J Cell Physiol ; 232(9): 2550-2557, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27731506

RESUMO

Phosphatidylinositol (PI) signaling is an essential regulator of cell motility and proliferation. A portion of PI metabolism and signaling takes place in the nuclear compartment of eukaryotic cells, where an array of kinases and phosphatases localize and modulate PI. Among these, Diacylglycerol Kinases (DGKs) are a class of phosphotransferases that phosphorylate diacylglycerol and induce the synthesis of phosphatidic acid. Nuclear DGKalpha modulates cell cycle progression, and its activity or expression can lead to changes in the phosphorylated status of the Retinoblastoma protein, thus, impairing G1/S transition and, subsequently, inducing cell cycle arrest, which is often uncoupled with apoptosis or autophagy induction. Here we report for the first time not only that the DGKalpha isoform is highly expressed in the nuclei of human erythroleukemia cell line K562, but also that its nuclear activity drives K562 cells through the G1/S transition during cell cycle progression. J. Cell. Physiol. 232: 2550-2557, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Núcleo Celular/enzimologia , Proliferação de Células , Diacilglicerol Quinase/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Leucemia Eritroblástica Aguda/enzimologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Proliferação de Células/efeitos dos fármacos , Diacilglicerol Quinase/antagonistas & inibidores , Diacilglicerol Quinase/genética , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Isoenzimas , Células K562 , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/patologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção
8.
Curr Opin Clin Nutr Metab Care ; 17(3): 236-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24572833

RESUMO

PURPOSE OF REVIEW: Muscle wasting is a comorbidity often associated with a wide range of disorders that severely affects patient prognosis and quality of life. Ghrelin, through its receptor GHSR-1a, stimulates appetite and growth hormone (GH) release. Several studies indicate that ghrelin administration is a valid treatment for cachexia because it improves muscle mass and function, likely by restoring a positive energy balance. RECENT FINDINGS: In addition to its GHSR-1a-mediated effects on muscle mass, ghrelin acts directly on skeletal muscle, wherein it exerts a protective activity against muscle wasting. This direct activity is independent of GHSR-1a and is shared by the unacylated form of ghrelin, which does not bind GHSR-1a and is devoid of the effects on appetite and GH release. SUMMARY: Both the acylated and unacylated forms of ghrelin might have therapeutic potential for the treatment of skeletal muscle wasting.


Assuntos
Grelina/química , Grelina/uso terapêutico , Atrofia Muscular/tratamento farmacológico , Síndrome de Emaciação/tratamento farmacológico , Acilação , Caquexia/tratamento farmacológico , Humanos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Atrofia Muscular/fisiopatologia , Receptores de Grelina/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-38591851

RESUMO

Although precision medicine moved its first steps from genomic medicine, it has gone far beyond genomics, considering the full complexity of cellular physiology. Therefore, the present time might be considered as the "post-genomic era." In detail, proteomics captures the overall protein profile of an analyzed sample. The goals of proteomic analysis are to perform a global analysis of protein expression and function, to systematically define the role proteins in physiological and pathological condition, to increase mechanistic understanding of the biological processes and to discover new biomarkers and therapeutic targets. In this narrative mini-review, the role of proteomics is discussed with a particular focus on the few attempts of the application of proteomic platforms for the identification of new biomarkers in pituitary diseases, namely in acromegaly, GH deficiency and male secondary hypogonadism.

10.
J Clin Endocrinol Metab ; 109(2): e522-e530, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37795977

RESUMO

CONTEXT: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver disease, affecting one-fourth of the adult population worldwide. Recent data found an association between MASLD and hypogonadism, but this relation in patients with type 2 diabetes mellitus (T2DM) is still unclear. OBJECTIVE: To evaluate in men with T2DM the association between total testosterone (TT) and noninvasive indices of hepatic steatosis (Fatty Liver Index [FLI], Hepatic Steatosis Index [HSI], Dallas Steatosis Index [DSI]) and fibrosis (AST to Platelet Ratio Index [APRI], Fibrosis-4 Index [FIB-4]), and their predictive cutoff values in identifying hypogonadism. METHODS: Cross-sectional study on 189 men with T2DM, without history of liver diseases and alcoholism, recruited on an outpatient basis. Interventions were andrological evaluation, metabolic parameters, TT, and liver indices. The main outcome measures were comparison of steatosis and fibrosis indices with testosterone levels and presence of hypogonadism. Receiver operating characteristic curves were used to identify cutoff values of liver indices in predicting low testosterone (<12 nmol/L). RESULTS: FLI, HSI, and DSI were negatively related with TT and were higher in the low-testosterone group than in the normal-testosterone group (FLI: 74.1 [61.4-93.5] vs 56.5 [32.1-78.2], P < .001; HSI: 41.5 [39.2-45.9] vs 40.1 [36.6-43.2], P = .005; DSI: 0.45 [-0.08-+1.04] vs -0.07 [-1.02-+0.58], P < .001). FLI and DSI also correlated with clinical symptoms of hypogonadism. No differences between groups were observed for APRI and FIB-4. FLI ≥63 was the best parameter as predictive index of low TT (sensitivity 73%, specificity 64%). CONCLUSION: We found an association between noninvasive indices of steatosis and hypogonadism in patients with T2DM. These indices could be used to direct the patients to andrological evaluation.


Assuntos
Diabetes Mellitus Tipo 2 , Fígado Gorduroso , Hipogonadismo , Adulto , Humanos , Masculino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Transversais , Hipogonadismo/complicações , Hipogonadismo/diagnóstico , Hipogonadismo/epidemiologia , Fígado Gorduroso/complicações , Testosterona , Fibrose
11.
Genes (Basel) ; 15(5)2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38790229

RESUMO

Several genes are implicated in spermatogenesis and fertility regulation, and these genes are presently being analysed in clinical practice due to their involvement in male factor infertility (MFI). However, there are still few genetic analyses that are currently recommended for use in clinical practice. In this manuscript, we reviewed the genetic causes of qualitative sperm defects. We distinguished between alterations causing reduced sperm motility (asthenozoospermia) and alterations causing changes in the typical morphology of sperm (teratozoospermia). In detail, the genetic causes of reduced sperm motility may be found in the alteration of genes associated with sperm mitochondrial DNA, mitochondrial proteins, ion transport and channels, and flagellar proteins. On the other hand, the genetic causes of changes in typical sperm morphology are related to conditions with a strong genetic basis, such as macrozoospermia, globozoospermia, and acephalic spermatozoa syndrome. We tried to distinguish alterations approved for routine clinical application from those still unsupported by adequate clinical studies. The most important aspect of the study was related to the correct identification of subjects to be tested and the correct application of genetic tests based on clear clinical data. The correct application of available genetic tests in a scenario where reduced sperm motility and changes in sperm morphology have been observed enables the delivery of a defined diagnosis and plays an important role in clinical decision-making. Finally, clarifying the genetic causes of MFI might, in future, contribute to reducing the proportion of so-called idiopathic MFI, which might indeed be defined as a subtype of MFI whose cause has not yet been revealed.


Assuntos
Motilidade dos Espermatozoides , Espermatozoides , Humanos , Masculino , Espermatozoides/metabolismo , Espermatozoides/patologia , Motilidade dos Espermatozoides/genética , Astenozoospermia/genética , Astenozoospermia/patologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Teratozoospermia/genética , Teratozoospermia/patologia , DNA Mitocondrial/genética , Testes Genéticos
12.
Antioxidants (Basel) ; 13(4)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38671937

RESUMO

To date, little is known concerning the circulating levels of biochemically relevant metabolites (antioxidants, oxidative/nitrosative stress biomarkers, purines, and pyrimidines) in patients with primary myelofibrosis (PMF), a rare form of myeloproliferative tumor causing a dramatic decrease in erythropoiesis and angiogenesis. In this study, using a targeted metabolomic approach, serum samples of 22 PMF patients and of 22 control healthy donors were analyzed to quantify the circulating concentrations of hypoxanthine, xanthine, uric acid (as representative purines), uracil, ß-pseudouridine, uridine (as representative pyrimidines), reduced glutathione (GSH), ascorbic acid (as two of the main water-soluble antioxidants), malondialdehyde, nitrite, nitrate (as oxidative/nitrosative stress biomarkers) and creatinine, using well-established HPLC method for their determination. Results showed that PMF patients have dramatic depletions of both ascorbic acid and GSH (37.3- and 3.81-times lower circulating concentrations, respectively, than those recorded in healthy controls, p < 0.0001), accompanied by significant increases in malondialdehyde (MDA) and nitrite + nitrate (4.73- and 1.66-times higher circulating concentrations, respectively, than those recorded in healthy controls, p < 0.0001). Additionally, PMF patients have remarkable alterations of circulating purines, pyrimidines, and creatinine, suggesting potential mitochondrial dysfunctions causing energy metabolism imbalance and consequent increases in these cell energy-related compounds. Overall, these results, besides evidencing previously unknown serum metabolic alterations in PMF patients, suggest that the determination of serum levels of the aforementioned compounds may be useful to evaluate PMF patients on hospital admission for adjunctive therapies aimed at recovering their correct antioxidant status, as well as to monitor patients' status and potential pharmacological treatments.

13.
Hematol Oncol ; 31(1): 22-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22488585

RESUMO

We investigated immunodeficiency-related non-Hodgkin lymphoma for the presence of molecular alterations affecting negative regulators of the Janus family protein tyrosine kinase/signal transducer and activator of transcription pathway. Protein tyrosine phosphatase, non-receptor type 6/Src homology 2-containing tyrosine phosphatase-1 epigenetic silencing was recurrent in primary effusion lymphoma (100%), and diffuse large B-cell lymphoma (63%), with a higher prevalence in the non-germinal centre subtype, and was associated with the activation of the Janus family protein tyrosine kinase/signal transducer and activator of transcription 3 pathway. Suppressor of cytokine signalling (SOCS)1 and SOCS3 epigenetic silencing were occasionally detected, whereas SOCS1 was frequently mutated in diffuse large B-cell lymphoma and polymorphic post-transplant lymphoproliferative disorders, possibly as a cause of aberrant somatic hypermutation. However, the mutation profile of the coding region of the gene was different from that expected from the aberrant somatic hypermutation process, suggesting that, at least in some cases, SOCS1 mutations may have been selected for their functional activity.


Assuntos
Citocinas/fisiologia , Metilação de DNA , Linfoma Relacionado a AIDS/genética , Transtornos Linfoproliferativos/genética , Proteínas de Neoplasias/genética , Complicações Pós-Operatórias/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Linhagem Celular Tumoral , Evolução Clonal , Análise Mutacional de DNA , DNA de Neoplasias/genética , Humanos , Hospedeiro Imunocomprometido , Janus Quinases/fisiologia , Linfoma Relacionado a AIDS/fisiopatologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/fisiopatologia , Mutação , Proteínas de Neoplasias/fisiologia , Transplante de Órgãos , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/fisiopatologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , Estudos Retrospectivos , Fatores de Transcrição STAT/fisiologia , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/fisiologia
14.
J Immunol ; 187(11): 5941-51, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22048771

RESUMO

Diacylglycerol kinases (DGKs) metabolize diacylglycerol to phosphatidic acid. In T lymphocytes, DGKα acts as a negative regulator of TCR signaling by decreasing diacylglycerol levels and inducing anergy. In this study, we show that upon costimulation of the TCR with CD28 or signaling lymphocyte activation molecule (SLAM), DGKα, but not DGKζ, exits from the nucleus and undergoes rapid negative regulation of its enzymatic activity. Inhibition of DGKα is dependent on the expression of SAP, an adaptor protein mutated in X-linked lymphoproliferative disease, which is essential for SLAM-mediated signaling and contributes to TCR/CD28-induced signaling and T cell activation. Accordingly, overexpression of SAP is sufficient to inhibit DGKα, whereas SAP mutants unable to bind either phospho-tyrosine residues or SH3 domain are ineffective. Moreover, phospholipase C activity and calcium, but not Src-family tyrosine kinases, are also required for negative regulation of DGKα. Finally, inhibition of DGKα in SAP-deficient cells partially rescues defective TCR/CD28 signaling, including Ras and ERK1/2 activation, protein kinase C membrane recruitment, induction of NF-AT transcriptional activity, and IL-2 production. Thus SAP-mediated inhibition of DGKα sustains diacylglycerol signaling, thereby regulating T cell activation, and it may represent a novel pharmacological strategy for X-linked lymphoproliferative disease treatment.


Assuntos
Diacilglicerol Quinase/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Western Blotting , Diglicerídeos/metabolismo , Imunofluorescência , Humanos , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Células Jurkat , Transporte Proteico/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transfecção
15.
Proc Natl Acad Sci U S A ; 107(9): 4182-7, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20160093

RESUMO

Diacylglycerol kinases (DGKs) convert diacylglycerol (DAG) into phosphatidic acid (PA), acting as molecular switches between DAG- and PA-mediated signaling. We previously showed that Src-dependent activation and plasma membrane recruitment of DGKalpha are required for growth-factor-induced cell migration and ruffling, through the control of Rac small-GTPase activation and plasma membrane localization. Herein we unveil a signaling pathway through which DGKalpha coordinates the localization of Rac. We show that upon hepatocyte growth-factor stimulation, DGKalpha, by producing PA, provides a key signal to recruit atypical PKCzeta/iota (aPKCzeta/iota) in complex with RhoGDI and Rac at ruffling sites of colony-growing epithelial cells. Then, DGKalpha-dependent activation of aPKCzeta/iota mediates the release of Rac from the inhibitory complex with RhoGDI, allowing its activation and leading to formation of membrane ruffles, which constitute essential requirements for cell migration. These findings highlight DGKalpha as the central element of a lipid signaling pathway linking tyrosine kinase growth-factor receptors to regulation of aPKCs and RhoGDI, and providing a positional signal regulating Rac association to the plasma membrane.


Assuntos
Diacilglicerol Quinase/metabolismo , Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Proteína Quinase C/metabolismo , Proteínas rac de Ligação ao GTP/metabolismo , Animais , Linhagem Celular , Membrana Celular/fisiologia , Cães , Imunofluorescência , Fosforilação , Transdução de Sinais , Inibidores da Dissociação do Nucleotídeo Guanina rho-Específico
16.
Front Reprod Health ; 5: 1219239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881222

RESUMO

Obstructive sleep apnoea syndrome (OSAS) is an under-recognized medical disease. The main risk factors for OSAS are male sex, older age, obesity, and metabolic syndrome, that are also associated with male hypogonadism (MH). Therefore, obesity has been classically identified as the most evident link between OSAS and MH. However, OSAS is per se linked to the development of MH by a combined effect of hypoxia, increased night-time awakenings, reduced sleep efficiency and fragmented sleep. Similarly, MH might represent a risk factor for OSAS, mainly related to sleep disturbances that are frequently associated with low testosterone. Data on testosterone replacement therapy (TRT) in patients with OSAS are limited. Nevertheless, TRT is generally contraindicated by guidelines in the presence of untreated or severe OSAS. TRT might in fact worse OSAS symptoms in different ways. Furthermore, OSAS has been proposed to be a risk factor for secondary polycythaemia and TRT might exacerbate polycythaemia. Therefore, TRT in hypogonadal men affected by untreated OSAS or severe OSAS should be considered with caution and in a personalised way. Nevertheless, the type and dosage of TRT should be considered, as short-term high-dose TRT might worsen OSAS, whereas long-term lower doses could eventually determine a clinical improvement of symptoms of OSAS. Here we reviewed the data on the association between OSAS, MH and TRT, including the opportunity of assessment of patients who develop signs and symptoms of OSAS during TRT by polysomnography.

17.
Artigo em Inglês | MEDLINE | ID: mdl-37345245

RESUMO

BACKGROUND: Ketosis-prone diabetes (KPD) is an emerging entity, sharing features of both type 1 diabetes mellitus and type 2 diabetes mellitus. Patients with KPD usually present with diabetic ketoacidosis without the classic phenotype of autoimmune type 1 diabetes. In most cases, they are Afro-American adults, who require insulin therapy for the management of acute decompensation, then usually encountering insulin-free remission for prolonged periods of time with diet or with non-insulin agents. Meanwhile, hypogonadism is a known condition that could be associated with higher risk of developing both type 1 and type 2 diabetes and could be a risk factor for decompensated diabetes. The association of KPD and hypogonadism is reported for the first time in literature. CASE PRESENTATION: Here we report two peculiar cases of young African patients, affected by KPD and hypergonadotropic hypogonadism, respectively Klinefelter's syndrome and primary ovarian failure. Both patients were treated promptly for the ketoacidosis with intravenous fluids combined with continuous insulin infusion, and then switched to subcutaneous regimen. After the correct clinical evaluation, oral antidiabetic drugs were added. CONCLUSION: KPD remains an under-recognized and under-diagnosed type of diabetes. As hypogonadism is strongly linked to dysmetabolic disorders, the evaluation of sex hormones should be performed at the onset of diabetes. Further studies should investigate the hypothalamic-pituitary-gonadal axis and its role in the development of KDP and its manifestations and complications.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Cetoacidose Diabética , Hipogonadismo , Cetose , Adulto , Humanos , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cetoacidose Diabética/complicações , Cetoacidose Diabética/diagnóstico , Cetoacidose Diabética/tratamento farmacológico , Insulina/uso terapêutico , Cetose/complicações , Cetose/tratamento farmacológico , Hipogonadismo/complicações , Hipogonadismo/diagnóstico , Hipogonadismo/tratamento farmacológico
18.
Endocr Connect ; 12(8)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37166398

RESUMO

Low bone mass is common in men with Klinefelter syndrome (KS), with a prevalence of 6-15% of osteoporosis and of 25-48% of osteopenia. Reduced bone mass has been described since adolescence and it might be related to both reduced bone formation and higher bone resorption. Although reduced testosterone levels are clearly involved in the pathogenesis, this relation is not always evident. Importantly, fracture risk is increased independently from bone mineral density (BMD) and testosterone levels. Here we discuss the pathogenesis of osteoporosis in patients with KS, with a particular focus on the role of testosterone and testis function. In fact, other hormonal mechanisms, such as global Leydig cell dysfunction, causing reduced insulin-like factor 3 and 25-OH vitamin D levels, and high follicle-stimulating hormone and estradiol levels, might be involved. Furthermore, genetic aspects related to the supernumerary X chromosome might be involved, as well as androgen receptor expression and function. Notably, body composition, skeletal mass and strength, and age at diagnosis are other important aspects. Although dual-energy x-ray absorptiometry is recommended in the clinical workflow for patients with KS to measure BMD, recent evidence suggests that alterations in the microarchitecture of the bones and vertebral fractures might be present even in subjects with normal BMD. Therefore, analysis of trabecular bone score, high-resolution peripheral quantitative computed tomography and vertebral morphometry seem promising tools to better estimate the fracture risk of patients with KS. This review also summarizes the evidence on the best available treatments for osteoporosis in men with KS, with or without hypogonadism.

19.
Life (Basel) ; 13(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37763258

RESUMO

Although precision medicine took its first steps from genomic medicine, it has gone far beyond genomics, considering the full complexity of cellular physiology. Therefore, the present time can be considered as the "post-genomic era". In detail, proteomics captures the overall protein profile of an analyzed sample, whilst metabolomics has the purpose of studying the molecular aspects of a known medical condition through the measurement of metabolites with low molecular weight in biological specimens. In this review, the role of post-genomic platforms, namely proteomics and metabolomics, is evaluated with a specific interest in their application for the identification of novel biomarkers in male hypogonadism and in the identification of new perspectives of knowledge on the pathophysiological function of testosterone. Post-genomic platforms, including MS-based proteomics and metabolomics based on ultra-high-performance liquid chromatography-HRMS, have been applied to find solutions to clinical questions related to the diagnosis and treatment of male hypogonadism. In detail, seminal proteomics helped us in identifying novel non-invasive markers of androgen activity to be translated into clinical practice, sperm proteomics revealed the role of testosterone in spermatogenesis, while serum metabolomics helped identify the different metabolic pathways associated with testosterone deficiency and replacement treatment, both in patients with insulin sensitivity and patients with insulin resistance.

20.
Life (Basel) ; 13(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37629557

RESUMO

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is defined as urologic pain or discomfort in the pelvic region, associated with urinary symptoms and/or sexual dysfunction, lasting for at least 3 of the previous 6 months. The rate of symptoms related to prostatitis has a mean prevalence of 8-8.2%. CP/CPPS is most frequent in men younger than 50 years, among whom it is the most common urologic diagnosis. In the last decades, many studies have been published on CP/CPPS and its association with male infertility. The pathophysiologic relation between CP/CPPS and male infertility involves several aspects, which are not well studied yet. A reduction in semen parameters has been demonstrated in patients with CP/CPPS, and several mechanisms have been proposed to represent putative pathophysiological links between CP/CPPS and infertility, including male accessory gland inflammation, metabolic syndrome, inflammatory bowel disease, HPV co-infection and autoimmunity. In light of this evidence, a multidisciplinary approach is advocated for patients with known CP/CPPS, and particular attention is needed for male patients of infertile couples in order to evaluate male accessory glands correctly. In addition, it is advisable that future studies dealing with the treatment of CP/CPPS take into consideration all the different pathophysiological aspects implicated.

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