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2.
Geroscience ; 45(5): 2805-2817, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37209203

RESUMO

DNAmPhenoAge, DNAmGrimAge, and the newly developed DNAmFitAge are DNA methylation (DNAm)-based biomarkers that reflect the individual aging process. Here, we examine the relationship between physical fitness and DNAm-based biomarkers in adults aged 33-88 with a wide range of physical fitness (including athletes with long-term training history). Higher levels of VO2max (ρ = 0.2, p = 6.4E - 4, r = 0.19, p = 1.2E - 3), Jumpmax (p = 0.11, p = 5.5E - 2, r = 0.13, p = 2.8E - 2), Gripmax (ρ = 0.17, p = 3.5E - 3, r = 0.16, p = 5.6E - 3), and HDL levels (ρ = 0.18, p = 1.95E - 3, r = 0.19, p = 1.1E - 3) are associated with better verbal short-term memory. In addition, verbal short-term memory is associated with decelerated aging assessed with the new DNAm biomarker FitAgeAcceleration (ρ: - 0.18, p = 0.0017). DNAmFitAge can distinguish high-fitness individuals from low/medium-fitness individuals better than existing DNAm biomarkers and estimates a younger biological age in the high-fit males and females (1.5 and 2.0 years younger, respectively). Our research shows that regular physical exercise contributes to observable physiological and methylation differences which are beneficial to the aging process. DNAmFitAge has now emerged as a new biological marker of quality of life.


Assuntos
Metilação de DNA , Qualidade de Vida , Masculino , Feminino , Humanos , Envelhecimento/genética , Exercício Físico , Biomarcadores
3.
J Diet Suppl ; 20(2): 218-253, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33977807

RESUMO

Overall mental health depends in part on the blood-brain barrier, which regulates nutrient transfer in-and-out of the brain and its central nervous system. Lactoferrin, an innate metal-transport protein, synthesized in the substantia nigra, particularly in dopaminergic neurons and activated microglia is vital for brain physiology. Lactoferrin rapidly crosses the blood-brain barrier via receptor-mediated transcytosis and accumulates in the brain capillary endothelial cells. Lactoferrin receptors are additionally present on glioma cells, brain micro-vessels, and neurons. As a regulator of neuro-redox, microglial lactoferrin is critical for protection/repair of neurons and healthy brain function. Iron imbalance and oxidative stress are common among patients with neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, dementia, depression, and multiple sclerosis. As an endogenous iron-chelator, lactoferrin prevents iron accumulation and dopamine depletion in Parkinson's disease patients. Oral lactoferrin supplementation could modulate the p-Akt/PTEN pathway, reduce Aß deposition, and ameliorate cognitive decline in Alzheimer's disease. Novel lactoferrin-based nano-therapeutics have emerged as effective drug-delivery systems for clinical management of neurodegenerative disorders. Recent emergence of the Coronavirus disease-2019 (COVID-19) pandemic, initially considered a respiratory illness, demonstrated a broader virulence spectrum with the ability to cross the blood-brain barrier and inflict a plethora of neuropathological manifestations in the brain - the Neuro-COVID-19. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are widely reported in Parkinson's disease, Alzheimer's disease, dementia, and multiple sclerosis patients with aggravated clinical outcomes. Lactoferrin, credited with several neuroprotective benefits in the brain could serve as a potential adjuvant in the clinical management of Neuro-COVID-19.


Assuntos
Doença de Alzheimer , COVID-19 , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Doença de Parkinson , Humanos , Barreira Hematoencefálica/metabolismo , Lactoferrina/metabolismo , Lactoferrina/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Saúde Mental , Células Endoteliais/metabolismo , SARS-CoV-2/metabolismo , Ferro/metabolismo , Ferro/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Oxirredução
5.
Ther Adv Urol ; 14: 17562872221109023, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35924206

RESUMO

Nanotechnology represents an expanding area of research and innovation in almost every field of science, including Medicine, where nanomaterial-based products have been developed for diagnostic and therapeutic applications. Because of their small, nanoscale size, these materials exhibit unique physical and chemical properties that differ from those of each component when considered in bulk. In Nanomedicine, there is an increasing interest in harnessing these unique properties to engineer nanocarriers for the delivery of therapeutic agents. Nano-based drug delivery platforms have many advantages over conventional drug administration routes as this technology allows for local and transdermal applications of therapeutics that can bypass the first-pass metabolism, improves drug efficacy through encapsulation of hydrophobic drugs, and allows for a sustained and controlled release of encapsulated agents. In Urology, nano-based drug delivery platforms have been extensively investigated and implemented for cancer treatment. However, there is also great potential for use of nanotechnology to treat non-oncologic urogenital diseases. We provide an update on research that is paving the way for clinical translation of nanotechnology in the areas of erectile dysfunction (ED), overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and catheter-associated urinary tract infections (CAUTIs). Overall, preclinical and clinical studies have proven the utility of nanomaterials both as vehicles for transdermal and intravesical delivery of therapeutic agents and for urinary catheter formulation with antimicrobial agents to treat non-oncologic urogenital diseases. Although clinical translation will be dependent on overcoming regulatory challenges, it is inevitable before there is universal adoption of this technology to treat non-oncologic urogenital diseases.

6.
Free Radic Biol Med ; 190: 15, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35933053
7.
Nat Metab ; 4(6): 651-662, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35760871

RESUMO

Multiple roles of reactive oxygen species (ROS) and their consequences for health and disease are emerging throughout biological sciences. This development has led researchers unfamiliar with the complexities of ROS and their reactions to employ commercial kits and probes to measure ROS and oxidative damage inappropriately, treating ROS (a generic abbreviation) as if it were a discrete molecular entity. Unfortunately, the application and interpretation of these measurements are fraught with challenges and limitations. This can lead to misleading claims entering the literature and impeding progress, despite a well-established body of knowledge on how best to assess individual ROS, their reactions, role as signalling molecules and the oxidative damage that they can cause. In this consensus statement we illuminate problems that can arise with many commonly used approaches for measurement of ROS and oxidative damage, and propose guidelines for best practice. We hope that these strategies will be useful to those who find their research requiring assessment of ROS, oxidative damage and redox signalling in cells and in vivo.


Assuntos
Antioxidantes , Estresse Oxidativo , Antioxidantes/metabolismo , Oxirredução , Espécies Reativas de Oxigênio , Transdução de Sinais
8.
J Mens Health ; 18(2)2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35547856

RESUMO

Background and objective: A growing body of literature suggests modulated expression of members of the opiorphin family of genes (PROL1, SMR3A and SMR3B) is associated with cancer. Recently, overexpression of PROL1 was shown to be associated with prostate cancer, with evidence of a role in overcoming the hypoxic barrier that develops as tumors grow. The primary goal of the present studies was to support and expand evidence for a role of PROL1 in the development and progression of prostate cancer. Material and methods: We engineered knock-out of the opiorphin gene, PROL1, in LNCaP, an androgen-sensitive, human prostate cancer derived, cell-line. Using xenograft assays, we compared the ability of injected LNCaP PROL1 knock-out cell-lines to develop tumors in both castrated and intact male mice with the parental LNCaP and LNCaP PROL1 overexpressing cell-lines. We used RNAseq to compare global gene expression between the parental and LNCaP PROL1 knock-out cell-lines. Wound closure and 3D spheroid invasion assays were used to compare cell motility and migration between parental LNCaP cells and LNCaP cells overexpressing of PROL1. Results: The present studies demonstrate that LNCaP cell-lines with consisitutive knock-out of PROL1 fail to develop tumors when injected into both castrated and intact male mice. Using RNAseq to compare global gene expression between the parental and LNCaP PROL1 knock-out cell-lines, we confirmed a role for PROL1 in regulating molecular pathways associated with angiogenesis and tumor blood supply, and also identified a potential role in pathways related to cell motility and migration. Through the use of wound closure and 3D spheroid invasion assays, we confirmed that overexpression of PROL1 in LNCaP cells leads to greater cell motility and migration compared to parental cells, suggesting that PROL1 overexpression results in a more invasive phenotype. Conclusion: Overall, our studies add to the growing body of evidence that opiorphin-encoding genes play a role in cancer development and progression. PROL1 is essential for establishment and growth of tumors in mice injected with LNCaP cells, and we provide evidence that PROL1 has a possible role in progression towards a more invasive, metastatic and castration resistant prostate cancer (PrCa).

9.
Int J Impot Res ; 34(6): 573-580, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34017115

RESUMO

Patients undergoing radical prostatectomy (RP) have a high incidence of postoperative erectile dysfunction (ED) refractory to treatment by oral phosphodiesterase-5 inhibitors (PDE5i). In the present studies, we investigated if a topically applied, nitric oxide microparticle delivery system (NO-MP) might act synergistically with an oral PDE5i (sildenafil) to improve erectile function outcomes in a rat model of RP. Thirty-five Sprague-Dawley rats underwent bilateral transection of the cavernous nerve (CN) for 1 week. After 1 week, animals were orally administered 0, 0.05, or 0.005 mg sildenafil/kg and the erectile response following topical application to the penile shaft of 250 or 100 mg NO-MP, or blank-MP, was monitored over a 2-h timeframe by recording the intracorporal pressure normalized to systemic blood pressure (ICP/BP, N = 5 animals/treatment group). Oral treatment with sildenafil by itself resulted in no observable erectile response. However, a combination of orally administered 0.05 sildenafil/kg with topical application of 250 mg NO-MP, compared to 250 mg NO-MP by itself, resulted in significantly more spontaneous erections (4.6 compared to 2 erections per hour, t-test; p value = 0.043), with a significantly faster onset for the first erectile response (11 compared to 22 min; t-test, p value = 0.041). Our results demonstrate a synergistic effect between orally administered PDE5i and topically applied NO-MP in eliciting an erectile response. Furthermore, they suggest a potential novel therapeutic approach to treat men with ED resulting from RP, through combination therapy of a topically applied NO-MP and an orally administered PDE5i.


Assuntos
Disfunção Erétil , Inibidores da Fosfodiesterase 5 , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/uso terapêutico , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Humanos , Masculino , Óxido Nítrico , Ereção Peniana , Inibidores da Fosfodiesterase 5/farmacologia , Inibidores da Fosfodiesterase 5/uso terapêutico , Prostatectomia/efeitos adversos , Ratos , Ratos Sprague-Dawley , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/uso terapêutico
10.
J Diet Suppl ; 19(1): 115-142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33164601

RESUMO

Coronavirus Disease 2019 (COVID-19) triggered by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection has been declared a pandemic by the World Health Organization (WHO) on March 11, 2020. Oxidative stress and its related metabolic syndromes are potential risk factors in the susceptibility to, and severity of COVID-19. In concert with the earliest reports of COVID-19, obstetricians started to diagnose and treat SARS-CoV-2 infections during pregnancy ("COVID-19-Pregnancy"). High metabolic demand to sustain normal fetal development increases the burden of oxidative stress in pregnancy. Intracellular redox changes intertwined with acute phase responses at the maternal-fetal interface could amplify during pregnancy. Interestingly, mother-to-fetus transmission of SARS-CoV-2 has not been detected in most of the COVID-19-Pregnancy cases. This relative absence of vertical transmission may be related to the presence of lactoferrin in the placenta, amniotic fluid, and lacteal secretions. However, the cytokine-storm induced during COVID-19-Pregnancy may cause severe inflammatory damage to the fetus, and if uncontrolled, may later result in autism spectrum-like disorders and brain development abnormalities in neonates. Considering this serious health threat to child growth and development, the prevention of COVID-19 during pregnancy should be considered a high priority. This review summarizes the intricate virulence factors of COVID-19 and elucidate its pathobiological spectrum during pregnancy and postpartum periods with a focus on the putative and complex roles of endogenous and exogenous lactoferrin in conferring immunological advantage to the host.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Criança , Feminino , Humanos , Recém-Nascido , Pandemias , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , SARS-CoV-2
11.
J Diet Suppl ; 19(1): 78-114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33164606

RESUMO

As the COVID-19 pandemic intensified the global health crisis, the containment of SARS-CoV-2 infection in pregnancies, and the inherent risk of vertical transmission of virus from mother-to-fetus (or neonate) poses a major concern. Most COVID-19-Pregnancy patients showed mild to moderate COVID-19 pneumonia with no pregnancy loss and no congenital transmission of the virus; however, an increase in hypoxia-induced preterm deliveries was apparent. Also, the breastmilk of several mothers with COVID-19 tested negative for the virus. Taken together, the natural barrier function during pregnancy and postpartum seems to deter the SARS-CoV-2 transmission from mother-to-child. This clinical observation warrants to explore the maternal-fetal interface and identify the innate defense factors for prevention and control of COVID-19-Pregnancy. Lactoferrin (LF) is a potent antiviral iron-binding protein present in the maternal-fetal interface. In concert with immune co-factors, maternal-LF modulates chemokine release and lymphocyte migration and amplify host defense during pregnancy. LF levels during pregnancy may resolve hypertension via down-regulation of ACE2; consequently, may limit the membrane receptor access to SARS-CoV-2 for cellular entry. Furthermore, an LF-derived peptide (LRPVAA) has been shown to block ACE receptor activity in vitro. LF may also reduce viral docking and entry into host cells and limit the early phase of COVID-19 infection. An in-depth understanding of LF and other soluble mammalian milk-derived innate antiviral factors may provide insights to reduce co-morbidities and vertical transmission of SARS-CoV-2 infection and may lead to the development of effective nutraceutical supplements.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Pandemias , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , SARS-CoV-2
12.
Andrologia ; 54(1): e14247, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34514620

RESUMO

Pelvic surgery, even without direct cavernous nerve injury, carries a high risk of post-operative erectile dysfunction. The present studies were aimed at identifying molecular mechanisms by which pelvic surgery results in erectile dysfunction. As a model of pelvic surgery, male Sprague-Dawley rats underwent pelvic laparotomy, avoiding direct cavernous nerve injury. A second group of animals, serving as a model of direct cavernous nerve injury, underwent bilateral transection of the cavernous nerve. Cavernosometry demonstrated, that even in the absence of direct nerve injury, the pelvic surgery model exhibited significant erectile dysfunction 3 days post-operatively. Gene expression profiling also demonstrated that even in this animal model of nerve-sparing pelvic surgery, the profile of differentially expressed genes in cavernosal tissue was indicative of cavernous nerve injury. In addition, although 6 hr after surgery there were significant changes in circulating cytokine/chemokine levels, an inflammatory response in the major pelvic ganglion, cavernous nerve and cavernosal tissue was only observed 3 days post-surgery. Our results validate a rat model of pelvic surgery exhibiting erectile dysfunction and suggest systemic release of cytokines/chemokines following surgical trauma might mediate a pathological inflammatory response in tissues distal to the site of surgical trauma, indirectly resulting in cavernous nerve injury and erectile dysfunction.


Assuntos
Disfunção Erétil , Animais , Modelos Animais de Doenças , Disfunção Erétil/etiologia , Expressão Gênica , Humanos , Masculino , Ereção Peniana , Pênis , Ratos , Ratos Sprague-Dawley
13.
Ther Clin Risk Manag ; 17: 589-599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113116

RESUMO

A need exists for local (ie, bladder-specific) interventions to treat overactive bladder (OAB) with low risk of unwanted postprocedural outcomes. Gene therapy targeted to leverage endogenous physiology in bladder cells may assist in restoring normal cell and organ function. Herein, we review the potential promise of gene therapy for treating OAB, focusing on gene transfer of URO-902, a non-viral naked plasmid DNA expressing the big potassium (BK) channel. We searched PubMed for articles concerning functional aspects of the BK channel and its potential use for gene transfer as local OAB treatment. Results from preclinical, phase 1, and phase 2 studies of URO-902 for erectile dysfunction and phase 1 studies of URO-902 for OAB are included. The BK channel has been extensively studied; however, URO-902 is the first gene therapy used in clinical trials directed toward treating OAB via the BK channel. In both URO-902 studies, there were no serious adverse events considered treatment related and no adverse events leading to early withdrawal. Both studies included secondary efficacy endpoints with promising results suggesting improvement in OAB symptoms, and quality of life, with use of URO-902 versus placebo. Gene therapy involving the BK channel, such as gene transfer with URO-902, has demonstrated promising safety and efficacy results in women with OAB. Findings warrant further investigation of the use of URO-902 for OAB treatment.

14.
Sex Med ; 9(3): 100343, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34000480

RESUMO

INTRODUCTION: Current non-invasive treatments for erectile dysfunction (ED) include oral medications, intracavernosal injections, and vacuum-assisted devices. Though these therapies work well for many, a subset of patients have contraindications or are unsatisfied with these options. Restorative therapies for ED are a new frontier of treatments focused on regenerating diseased tissue and providing a potential "cure" for ED. AIM: The aim of this position statement is to examine existing clinical trial data for restorative therapies and identify elements that require further research before widespread adoption. METHODS: A literature review was performed to identify all clinical trials performed with regenerative therapy for ED. This includes treatments such as stem cell therapy (SCT), platelet rich plasma (PRP), and restorative related technologies like low-intensity shockwave therapy (LiSWT). MAIN OUTCOME MEASURES: Most clinical trials in restorative therapies were assessed for safety, feasibility, or efficacy. This included recording adverse events, changes in sexual function and erectile function questionnaires, and diagnostics measures. RESULTS: To date there is an absence of robust clinical data supporting the efficacy of restorative therapies regarding ED, though technologies such as LiSWT have established relative safety. CONCLUSIONS: Restorative therapies are a promising technology that represents a new frontier of treatment geared towards reversing disease pathology rather than just treating symptoms. However, current published clinical studies are limited. Future work needs to be adequately powered, multi-center, randomized, sham/placebo-controlled trials in well-characterized patient populations to ensure safety and demonstrate efficacy. Until these studies are done, restorative therapies should be reserved for clinical trials and not offered in routine clinical practice. Liu JL, Chu KY, Gabrielson AT, et al. Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA). J Sex Med 2021;9:100343.

15.
JCI Insight ; 6(9)2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33872220

RESUMO

The microtubule (MT) cytoskeleton plays a critical role in axon growth and guidance. Here, we identify the MT-severing enzyme fidgetin-like 2 (FL2) as a negative regulator of axon regeneration and a therapeutic target for promoting nerve regeneration after injury. Genetic knockout of FL2 in cultured adult dorsal root ganglion neurons resulted in longer axons and attenuated growth cone retraction in response to inhibitory molecules. Given the axonal growth-promoting effects of FL2 depletion in vitro, we tested whether FL2 could be targeted to promote regeneration in a rodent model of cavernous nerve (CN) injury. The CNs are parasympathetic nerves that regulate blood flow to the penis, which are commonly damaged during radical prostatectomy (RP), resulting in erectile dysfunction (ED). Application of FL2-siRNA after CN injury significantly enhanced functional nerve recovery. Remarkably, following bilateral nerve transection, visible and functional nerve regeneration was observed in 7 out of 8 animals treated with FL2-siRNA, while no control-treated animals exhibited regeneration. These studies identify FL2 as a promising therapeutic target for enhancing regeneration after peripheral nerve injury and for mitigating neurogenic ED after RP - a condition for which, at present, only poor treatment options exist.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/fisiologia , Orientação de Axônios/genética , Axônios/metabolismo , Gânglios Espinais/citologia , Proteínas Associadas aos Microtúbulos/fisiologia , Regeneração Nervosa/genética , Neurônios/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo , ATPases Associadas a Diversas Atividades Celulares/genética , Animais , Células Cultivadas , Masculino , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos , Pênis/inervação , Prostatectomia , Interferência de RNA , RNA Interferente Pequeno
16.
Future Oncol ; 17(17): 2209-2223, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33593085

RESUMO

Background: We describe the first studies investigating a role for opiorphin genes (PROL1, SMR3A and SMR3B) in prostate cancer (PrCa). Materials & methods: Databases and PrCa tissue arrays were screened for opiorphin expression. Xenografted tumor growth of human PrCa cells overexpressing PROL1 was compared with controls in nude mice. Modulated gene expression by overexpression of PROL1 was determined by RNA sequencing. Results: PrCa is associated with overexpression of opiorphin genes. Xenografted androgen-sensitive PrCa cells overexpressing PROL1 developed into tumors in castrated male mice (in contrast to parental cells). PROL1 overexpression modulates expression of genes in angiogenesis, steroid and hypoxic response pathways. Conclusions: Opiorphins promote the development of androgen-insensitive PrCa and activate pathways that potentially overcome the hypoxic barrier generated during tumor growth.


Assuntos
Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Oligopeptídeos/metabolismo , Neoplasias da Próstata/patologia , Proteínas e Peptídeos Salivares/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Humanos , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Oligopeptídeos/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas e Peptídeos Salivares/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Ageing Res Rev ; 65: 101200, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33130247

RESUMO

Sarcopenia represents a muscle-wasting syndrome characterized by progressive and generalized degenerative loss of skeletal muscle mass, quality, and strength occurring during normal aging. Sarcopenia patients are mainly suffering from the loss in muscle strength and are faced with mobility disorders reducing their quality of life and are, therefore, at higher risk for morbidity (falls, bone fracture, metabolic diseases) and mortality. Several molecular mechanisms have been described as causes for sarcopenia that refer to very different levels of muscle physiology. These mechanisms cover e. g. function of hormones (e. g. IGF-1 and Insulin), muscle fiber composition and neuromuscular drive, myo-satellite cell potential to differentiate and proliferate, inflammatory pathways as well as intracellular mechanisms in the processes of proteostasis and mitochondrial function. In this review, we describe sarcopenia as a muscle-wasting syndrome distinct from other atrophic diseases and summarize the current view on molecular causes of sarcopenia development as well as open questions provoking further research efforts for establishing efficient lifestyle and therapeutic interventions.


Assuntos
Sarcopenia , Envelhecimento , Humanos , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Qualidade de Vida , Sarcopenia/patologia
18.
Physiol Rep ; 8(22): e14614, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33200530

RESUMO

Hyperglycemic memory is associated with several complications of diabetes. Although there is some physiological evidence that this phenomenon occurs with diabetic bladder dysfunction (DBD), there have been no studies in bladder that provide evidence of hyperglycemic memory at the molecular/biochemical level. In the present studies, we determined the effects of long-term diabetes on the metabolome of bladder detrusor in a rat model of streptozotocin-induced type-1-diabetes and the ability of insulin treatment to normalize metabolic changes. These studies demonstrated that although insulin reversed a majority of the metabolic changes caused by diabetes, with long-term diabetes there was a persistent decrease in the methylation index (indicated by a reduced ratio of S-adenosylmethionine to S-adenosyl homocysteine) after insulin treatment. We confirmed a "hypomethylated environment" develops in diabetic detrusor by demonstrating an overall reduction in methylated detrusor DNA that is only partially reversed with glycemic control. Furthermore, we confirmed that this hypomethylated environment is associated with epigenetic changes in the detrusor genome, which are again mostly, but not completely, reversed with glycemic control. Overall our studies provide strong molecular evidence for a mechanism by which diabetes alters methylation status and gene expression in the detrusor genome, and that these epigenetic modifications contribute to hyperglycemic memory. Our work suggests novel treatment strategies for diabetic patients who have attained glycemic control but continue to experience DBD. For example, epigenomic data can be used to identify "actionable gene targets" for its treatment and would also support a rationale for approaches that target the hypomethylation index.


Assuntos
Metilação de DNA , Diabetes Mellitus/metabolismo , Epigênese Genética , Hiperglicemia/metabolismo , Bexiga Urinária/metabolismo , Animais , Diabetes Mellitus/genética , Glucose/metabolismo , Hiperglicemia/genética , Masculino , Ratos , Ratos Endogâmicos F344
19.
Free Radic Biol Med ; 160: 67-77, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-32758664

RESUMO

Our studies center on the physiological phenomenon of adaptive homeostasis in which very low, signaling levels of an oxidant can induce transient expansion of the baseline homeostatic range of protective mechanisms, resulting in transient stress protection. The 20S proteasome is a major element of such inducible defense enzymes against oxidative stress but the relative importance of each of its three proteolytic subunits, ß1, ß2, and ß5, is only poorly understood. We focused the present studies on determining the role of the ß5 subunit in adaptation, survival, and lifespan. Decreased expression of the 20S proteasome ß5 subunit (with RNAi) blocked the adaptive increase in the catalytic activities of the 20S proteasome response to signaling levels of H2O2 in female flies. Similarly, female-specific adaptive increases in survival following H2O2 pretreatment and subsequent toxic challenge was blocked. In contrast, direct overexpression of the 20S proteasome ß5 subunit enabled an increased 20S proteasome proteolytic response, but prevented further adaptive homeostatic increases through H2O2 signaling, indicating there is a maximum 'ceiling' to the adaptive response. Males showed no adaptive change in proteasomal levels or activity whatsoever with H2O2 pretreatment and exhibited no significant impact upon the other 2 proteolytic subunits of the proteasome. However, chronic loss of the ß5 subunit led to shortened lifespan in both sexes. Our exploration of the importance of the 20S proteasome ß5 subunit in adaptive homeostasis highlights the interconnection between signal transduction pathways and regulated gene expression in sexually divergent responses to oxidative stimulation.


Assuntos
Drosophila melanogaster , Estresse Oxidativo , Complexo de Endopeptidases do Proteassoma , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Homeostase , Peróxido de Hidrogênio , Masculino , Complexo de Endopeptidases do Proteassoma/metabolismo
20.
Free Radic Biol Med ; 158: 53-59, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32682927

RESUMO

Glutathione (GSH) plays critical roles in the inflammatory response by acting as the master substrate for antioxidant enzymes and an important anti-inflammatory agent. In the early phase of the inflammatory response of macrophages, GSH content is decreased due to the down regulation of the catalytic subunit of glutamate cysteine ligase (GCLC). In the current study we investigated the underlying mechanism for this phenomenon. In human THP1-differentiated macrophages, GCLC mRNA had a half-life of 4 h under basal conditions, and it was significantly reduced to less than 2 h upon exposure to lipopolysaccharide (LPS), suggesting an increased decay of GCLC mRNA in the inflammatory response. The half-life of GCLC protein was >10 h under basal conditions, and upon LPS exposure the degradation rate of GCLC protein was significantly increased. The pan-caspase inhibitor Z-VAD-FMK but not the proteasome inhibitor MG132, prevented the down regulation of GCLC protein caused by LPS. Both caspase inhibitor Z-LEVD-FMK and siRNA of caspase-5 abrogated LPS-induced degradation of GCLC protein. In addition, supplement with γ-GC, the GCLC product, efficiently restored GSH content and suppressed the induction of NF-κB activity by LPS. In conclusion, these data suggest that GCLC down-regulation in the inflammatory response of macrophages is mediated through both increased mRNA decay and caspase-5-mediated GCLC protein degradation, and γ-GC is an efficient agent to restore GSH and regulate the inflammatory response.


Assuntos
Glutamato-Cisteína Ligase , Glutationa , Caspases/metabolismo , Regulação para Baixo , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Humanos , Macrófagos/metabolismo
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