RESUMO
BACKGROUND: Myoclonus, Epilepsy and Ragged-Red-Fibers (MERRF) is a mitochondrial encephalomyopathy due to heteroplasmic mutations in mitochondrial DNA (mtDNA) most frequently affecting the tRNALys gene at position m.8344A > G. Defective tRNALys severely impairs mitochondrial protein synthesis and respiratory chain when a high percentage of mutant heteroplasmy crosses the threshold for full-blown clinical phenotype. Therapy is currently limited to symptomatic management of myoclonic epilepsy, and supportive measures to counteract muscle weakness with co-factors/supplements. METHODS: We tested two therapeutic strategies to rescue mitochondrial function in cybrids and fibroblasts carrying different loads of the m.8344A > G mutation. The first strategy was aimed at inducing mitochondrial biogenesis directly, over-expressing the master regulator PGC-1α, or indirectly, through the treatment with nicotinic acid, a NAD+ precursor. The second was aimed at stimulating the removal of damaged mitochondria through prolonged rapamycin treatment. RESULTS: The first approach slightly increased mitochondrial protein expression and respiration in the wild type and intermediate-mutation load cells, but was ineffective in high-mutation load cell lines. This suggests that induction of mitochondrial biogenesis may not be sufficient to rescue mitochondrial dysfunction in MERRF cells with high-mutation load. The second approach, when administered chronically (4 weeks), induced a slight increase of mitochondrial respiration in fibroblasts with high-mutation load, and a significant improvement in fibroblasts with intermediate-mutation load, rescuing completely the bioenergetics defect. This effect was mediated by increased mitochondrial biogenesis, possibly related to the rapamycin-induced inhibition of the Mechanistic Target of Rapamycin Complex 1 (mTORC1) and the consequent activation of the Transcription Factor EB (TFEB). CONCLUSIONS: Overall, our results point to rapamycin-based therapy as a promising therapeutic option for MERRF.
Assuntos
Síndrome MERRF , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Humanos , Síndrome MERRF/genética , Síndrome MERRF/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , RNA de Transferência de Lisina/genética , RNA de Transferência de Lisina/metabolismo , Sirolimo/metabolismo , Sirolimo/farmacologiaRESUMO
Cannabis sativa L. is increasingly emerging for its protective role in modulating neuroinflammation, a complex process orchestrated among others by microglia, the resident immune cells of the central nervous system. Phytocannabinoids, especially cannabidiol (CBD), terpenes, and other constituents trigger several upstream and downstream microglial intracellular pathways. Here, we investigated the molecular mechanisms of a CBD- and terpenes-enriched C. sativa extract (CSE) in an in vitro model of neuroinflammation. We evaluated the effect of CSE on the inflammatory response induced by exposure to lipopolysaccharide (LPS) in BV-2 microglial cells, compared with CBD and ß-caryophyllene (CAR), CB2 receptors (CB2r) inverse and full agonist, respectively. The LPS-induced upregulation of the pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α was significantly attenuated by CSE and only partially by CBD, whereas CAR was ineffective. In BV-2 cells, these anti-inflammatory effects exerted by CSE phytocomplex were only partially dependent on CB2r modulation and they were mediated by the regulation of enzymes responsible for the endocannabinoids metabolism, by the inhibition of reactive oxygen species release and the modulation of JNK/p38 cascade with consequent NF-κB p65 nuclear translocation suppression. Our data suggest that C. sativa phytocomplex and its multitarget mechanism could represent a novel therapeutic strategy for neuroinflammatory-related diseases.
Assuntos
Canabidiol , Cannabis , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Citocinas/metabolismo , Endocanabinoides/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Microglia , NF-kappa B/metabolismo , Receptor CB2 de Canabinoide/metabolismoRESUMO
We here report on the existence of Leber's hereditary optic neuropathy (LHON) associated with peculiar combinations of individually non-pathogenic missense mitochondrial DNA (mtDNA) variants, affecting the MT-ND4, MT-ND4L and MT-ND6 subunit genes of Complex I. The pathogenic potential of these mtDNA haplotypes is supported by multiple evidences: first, the LHON phenotype is strictly inherited along the maternal line in one very large family; second, the combinations of mtDNA variants are unique to the two maternal lineages that are characterized by recurrence of LHON; third, the Complex I-dependent respiratory and oxidative phosphorylation defect is co-transferred from the proband's fibroblasts into the cybrid cell model. Finally, all but one of these missense mtDNA variants cluster along the same predicted fourth E-channel deputed to proton translocation within the transmembrane domain of Complex I, involving the ND1, ND4L and ND6 subunits. Hence, the definition of the pathogenic role of a specific mtDNA mutation becomes blurrier than ever and only an accurate evaluation of mitogenome sequence variation data from the general population, combined with functional analyses using the cybrid cell model, may lead to final validation. Our study conclusively shows that even in the absence of a clearly established LHON primary mutation, unprecedented combinations of missense mtDNA variants, individually known as polymorphisms, may lead to reduced OXPHOS efficiency sufficient to trigger LHON. In this context, we introduce a new diagnostic perspective that implies the complete sequence analysis of mitogenomes in LHON as mandatory gold standard diagnostic approach.
Assuntos
DNA Mitocondrial/genética , Herança Multifatorial , Mutação de Sentido Incorreto , Atrofia Óptica Hereditária de Leber/genética , Penetrância , Adulto , Sequência de Aminoácidos , Complexo I de Transporte de Elétrons/química , Complexo I de Transporte de Elétrons/genética , Epistasia Genética , Família , Feminino , Genes Mitocondriais , Humanos , Masculino , Modelos Moleculares , NADH Desidrogenase/química , NADH Desidrogenase/genética , Linhagem , Adulto JovemRESUMO
Resistance to chemotherapy still remains a major challenge in the clinic, impairing the quality of life and survival rate of patients. The identification of unconventional chemosensitizing agents is therefore an interesting aspect of cancer research. Resveratrol has emerged in the last decades as a fascinating molecule, able to modulate several cancer-related molecular mechanisms, suggesting a possible application as an adjuvant in cancer management. This review goes deep into the existing literature concerning the possible chemosensitizing effect of resveratrol associated with the most conventional chemotherapeutic drugs. Despite the promising effects observed in different cancer types in in vitro studies, the clinical translation still presents strong limitations due to the low bioavailability of resveratrol. Recently, efforts have been moved in the field of drug delivery to identifying possible strategies/formulations useful for a more effective administration. Despite the necessity of a huge implementation in this research area, resveratrol appears as a promising molecule able to sensitize resistant tumors to drugs, suggesting its potential use in therapy-refractory cancer patients.
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Antineoplásicos Fitogênicos/farmacologia , Resveratrol/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Resveratrol/uso terapêuticoRESUMO
Recently, there has been a great effort to develop tests based on non-invasive urinary biomarkers (NMIBCs). These tests are based on the fact that NMIBCs are heterogeneous at the molecular level and can be divided into different molecular groups useful to predict prognosis and response to treatment. The assessment of epigenetic alterations, such as DNA methylation, represents a promising cancer biomarker. DNA methylation is an epigenetic modification that affects gene expression without modifying the DNA sequence. Several studies have highlighted the presence of methylated loci in the context of bladder cancer, indicating its potential application as a diagnostic and prognostic biomarker. One of the novel assays based on a DNA methylation profile, the Bladder EpiCheck, analyzes DNA from spontaneous urine, detecting disease-specific DNA methylation patterns in bladder cancer patients. This test, due to its non-invasive nature and highly promising performance could, in future, become an invaluable tool in the follow-up of bladder cancer patients. Potential new applications could include diagnosis and surveillance of upper-tract disease, for the replacement of invasive testing and ureteroscopy.
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Biomarcadores Tumorais/urina , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Metilação de DNA/genética , Epigênese Genética/genética , Humanos , Prognóstico , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/urinaRESUMO
Cisplatin is the first-line treatment for different types of solid tumors, such as ovarian, testicular, bladder, cervical, head and neck, lung, and esophageal cancers. The main problem related to its clinical use is the onset of drug resistance. In the last decades, among the studied molecular mechanisms of cisplatin resistance, metabolic reprogramming has emerged as a possible one. This review focuses on the pentose phosphate pathway (PPP) playing a pivotal role in maintaining the high cell proliferation rate and representing an advantage for cancer cells. In particular, the oxidative branch of PPP plays a role in oxidative stress and seems to be involved in cisplatin resistance. In light of these considerations, it has been demonstrated that overexpression and higher enzymatic activity of different enzymes of both oxidative and non-oxidative branches (such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and transketolase) increase cisplatin resistance, and their silencing or combined treatment with cisplatin could restore cisplatin sensitivity. Moreover, drug delivery systems loaded with both PPP inhibitors and cisplatin give the possibility of reaching cancer cells selectively. In conclusion, targeting PPP is becoming a strategy to overcome cisplatin resistance; however, further studies are required to better understand the mechanisms.
Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Via de Pentose FosfatoRESUMO
Benign prostatic hyperplasia (BPH) is an age-related chronic disorder, characterized by the hyperproliferation of prostatic epithelial and stromal cells, which drives prostate enlargement. Since BPH aetiology and progression have been associated with the persistence of an inflammatory stimulus, induced both by Nuclear Factor-kappa B (NF-κB) activation and reactive oxygen species (ROS) production, the inhibition of these pathways could result in a good tool for its clinical treatment. This study aimed to evaluate the antioxidant and anti-inflammatory activity of a combined formulation of Serenoa repens and Urtica dioica (SR/UD) in an in vitro human model of BPH. The results confirmed both the antioxidant and the anti-inflammatory effects of SR/UD. In fact, SR/UD simultaneously reduced ROS production, NF-κB translocation inside the nucleus, and, consequently, interleukin 6 (IL-6) and interleukin 8 (IL-8) production. Furthermore, the effect of SR/UD was also tested in a human androgen-independent prostate cell model, PC3. SR/UD did not show any significant antioxidant and anti-inflammatory effect, but was able to reduce NF-κB translocation. Taken together, these results suggested a promising role of SR/UD in BPH and BPH-linked disorder prevention.
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Extratos Vegetais/farmacologia , Serenoa/química , Urtica dioica/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Masculino , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Hiperplasia Prostática/tratamento farmacológicoRESUMO
Cisplatin is one of the worldwide anticancer drugs and, despite its toxicity and frequent recurrence of resistance phenomena, it still remains the only therapeutic option for several tumors. Circumventing cisplatin resistance remains, therefore, a major goal for clinical therapy and represents a challenge for scientific research. Recent studies have brought to light the fundamental role of mitochondria in onset, progression, and metastasis of cancer, as well as its importance in the resistance to chemotherapy. The aim of this review is to give an overview of the current knowledge about the implication of mitochondria in cisplatin resistance and on the recent development in this research field. Recent studies have highlighted the role of mitochondrial DNA alterations in onset of resistance phenomena, being related both to redox balance alterations and to signal crosstalk with the nucleus, allowing a rewiring of cell metabolism. Moreover, an important role of the mitochondrial dynamics in the adaptation mechanism of cancer cells to challenging environment has been revealed. Giving bioenergetic plasticity to tumor cells, mitochondria allow cells to evade death pathways in stressful conditions, including chemotherapy. So far, even if the central role of mitochondria is recognized, little is known about the specific mechanisms implicated in the resistance. Nevertheless, mitochondria appear to be promising pharmacological targets for overcoming cisplatin resistance, but further studies are necessary.
Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Animais , Núcleo Celular/metabolismo , DNA Mitocondrial , Resistencia a Medicamentos Antineoplásicos , Humanos , Mitocôndrias/genética , Dinâmica Mitocondrial/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Transdução de SinaisRESUMO
There is growing evidence that the sequence variation of mitochondrial DNA (mtDNA), which clusters in population- and/or geographic-specific haplogroups, may result in functional effects that, in turn, become relevant in disease predisposition or protection, interaction with environmental factors and ultimately in modulating longevity. To unravel functional differences between mtDNA haplogroups we here employed transmitochondrial cytoplasmic hybrid cells (cybrids) grown in galactose medium, a culture condition that forces oxidative phosphorylation, and in the presence of rotenone, the classic inhibitor of respiratory Complex I. Under this experimental paradigm we assessed functional parameters such as cell viability and respiration, ATP synthesis, reactive oxygen species production and mtDNA copy number. Our analyses show that haplogroup J1, which is common in western Eurasian populations, is the most sensitive to rotenone, whereas K1 mitogenomes orchestrate the best compensation, possibly because of the haplogroup-specific missense variants impinging on Complex I function. Remarkably, haplogroups J1 and K1 fit the genetic associations previously established with Leber's hereditary optic neuropathy (LHON) for J1, as a penetrance enhancer, and with Parkinson's disease (PD) for K1, as a protective background. Our findings provide functional evidences supporting previous well-established genetic associations of specific haplogroups with two neurodegenerative pathologies, LHON and PD. Our experimental paradigm is instrumental to highlighting the subtle functional differences characterizing mtDNA haplogroups, which will be increasingly needed to dissect the role of mtDNA genetic variation in health, disease and longevity.
Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Haplótipos/genética , Doença de Parkinson Secundária/genética , Praguicidas/toxicidade , Rotenona/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , DNA Mitocondrial/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Genoma Mitocondrial/efeitos dos fármacos , Haplótipos/efeitos dos fármacos , Humanos , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Doença de Parkinson Secundária/induzido quimicamente , Filogenia , Estrutura Secundária de ProteínaRESUMO
Adenosine is a versatile signaling molecule recognized to physiologically influence gut motor functions. Both the duration and magnitude of adenosine signaling in enteric neuromuscular function depend on its availability, which is regulated by the ecto-enzymes ecto-5'-nucleotidase (CD73), alkaline phosphatase (AP), and ecto-adenosine deaminase (ADA) and by dipyridamole-sensitive equilibrative transporters (ENTs). Our purpose was to assess the involvement of CD73, APs, ecto-ADA in the formation of AMP-derived adenosine in primary cultures of ileal myofibroblasts (IMFs). IMFs were isolated from rat ileum longitudinal muscle segments by means of primary explant technique and identified by immunofluorescence staining for vimentin and α-smooth muscle actin. IMFs confluent monolayers were exposed to exogenous 5'-AMP in the presence or absence of CD73, APs, ecto-ADA, or ENTs inhibitors. The formation of adenosine and its metabolites in the IMFs medium was monitored by high-performance liquid chromatography. The distribution of CD73 and ADA in IMFs was detected by confocal immunocytochemistry and qRT-PCR. Exogenous 5'-AMP was rapidly cleared being almost undetectable after 60-min incubation, while adenosine levels significantly increased. Treatment of IMFs with CD73 inhibitors markedly reduced 5'-AMP clearance whereas ADA blockade or inhibition of both ADA and ENTs prevented adenosine catabolism. By contrast, inhibition of APs did not affect 5'-AMP metabolism. Immunofluorescence staining and qRT-PCR analysis confirmed the expression of CD73 and ADA in IMFs. Overall, our data show that in IMFs an extracellular AMP-adenosine pathway is functionally active and among the different enzymatic pathways regulating extracellular adenosine levels, CD73 and ecto-ADA represent the critical catabolic pathway.
Assuntos
5'-Nucleotidase/metabolismo , Adenosina Desaminase/metabolismo , Adenosina/metabolismo , Intestino Delgado/metabolismo , Miofibroblastos/metabolismo , Monofosfato de Adenosina/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Masculino , Ratos WistarRESUMO
Leber's hereditary optic neuropathy (LHON) is a maternally inherited blinding disease characterized by degeneration of retinal ganglion cells (RGCs) and consequent optic nerve atrophy. Peculiar features of LHON are incomplete penetrance and gender bias, with a marked male prevalence. Based on the different hormonal metabolism between genders, we proposed that estrogens play a protective role in females and showed that these hormones ameliorate mitochondrial dysfunction in LHON through the estrogen receptors (ERs). We also showed that ERß localize to the mitochondria of RGCs. Thus, targeting ERß may become a therapeutic strategy for LHON specifically aimed at avoiding or delaying the onset of disease in mutation carriers. Here, we tested the effects of ERß targeting on LHON mitochondrial defective metabolism by treating LHON cybrid cells carrying the m.11778G>A mutation with a combination of natural estrogen-like compounds that bind ERß with high selectivity. We demonstrated that these molecules improve cell viability by reducing apoptosis, inducing mitochondrial biogenesis and strongly reducing the levels of reactive oxygen species in LHON cells. These effects were abolished in cells with ERß knockdown by silencing receptor expression or by using specific receptor antagonists. Our observations support the hypothesis that estrogen-like molecules may be useful in LHON prophylactic therapy. This is particularly important for lifelong disease prevention in unaffected LHON mutation carriers. Current strategies attempting to combat degeneration of RGCs during the acute phase of LHON have not been very effective. Implementing a different and preemptive approach with a low risk profile may be very helpful.
Assuntos
Receptor beta de Estrogênio/antagonistas & inibidores , Atrofia Óptica Hereditária de Leber/prevenção & controle , Fitoestrógenos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Respiração Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Receptor beta de Estrogênio/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mutação , Atrofia Óptica Hereditária de Leber/metabolismo , Biogênese de Organelas , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio , Células Ganglionares da Retina/metabolismoRESUMO
Principal component analysis (PCA) multivariate analysis was applied to study the cytotoxic activity of essential oils from various species of the Pistacia genus on human tumor cell lines. In particular, the cytotoxic activity of essential oils obtained from P. lentiscus, P. lentiscus var. chia (mastic gum), P. terebinthus, P. vera, and P. integerrima, was screened on three human adenocarcinoma cell lines: MCF-7 (breast), 2008 (ovarian), and LoVo (colon). The results indicate that all the Pistacia phytocomplexes, with the exception of mastic gum oil, induce cytotoxic effects on one or more of the three cell lines. PCA highlighted the presence of different cooperating clusters of bioactive molecules. Cluster variability among species, and even within the same species, could explain some of the differences seen among samples suggesting the presence of both common and species-specific mechanisms. Single molecules from one of the most significant clusters were tested, but only bornyl-acetate presented cytotoxic activity, although at much higher concentrations (IC50 = 138.5 µg/mL) than those present in the essential oils, indicating that understanding of the full biological effect requires a holistic vision of the phytocomplexes with all its constituents.
Assuntos
Antineoplásicos/farmacologia , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Pistacia/química , Óleos de Plantas/farmacologia , Terpenos/farmacologia , Adenocarcinoma , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Resina Mástique/química , Análise Multivariada , Óleos Voláteis/química , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Análise de Componente PrincipalRESUMO
The genetic and epigenetic factors underlying the variable penetrance of homoplasmic mitochondrial DNA mutations are poorly understood. We investigated a 16-year-old patient with hypertrophic cardiomyopathy harboring a homoplasmic m.4277T>C mutation in the mt-tRNA(Ile) (MTTI) gene. Skeletal muscle showed multiple respiratory chain enzyme abnormalities and a decreased steady-state level of the mutated mt-tRNA(Ile). Transmitochondrial cybrids grown on galactose medium demonstrated a functional effect of this mutation on cell viability, confirming pathogenicity. These findings were reproduced in transmitochondrial cybrids, harboring a previously described homoplasmic m.4300A>G MTTI mutation. The pathogenic role of the m.4277T>C mutation may be ascribed to misfolding of the mt-tRNA molecule, as demonstrated by the altered electrophoretic migration of the mutated mt-tRNA. Indeed, structure and sequence analyses suggest that thymidine at position 4277 of mt-tRNA(Ile) is involved in a conserved tertiary interaction with thymidine at position 4306. Interestingly, the mutation showed variable penetrance within family members, with skeletal muscle from the patient's clinically unaffected mother demonstrating normal muscle respiratory chain activities and steady-state levels of mt-tRNA(Ile), while homoplasmic for the m.4277T>C mutation. Analysis of mitochondrial isoleucyl-tRNA synthetase revealed significantly higher expression levels in skeletal muscle and fibroblasts of the unaffected mother when compared with the proband, while the transient over-expression of the IARS2 gene in patient transmitochondrial cybrids improved cell viability. This is the first observation that constitutively high levels of aminoacyl-tRNA synthetases (aaRSs) in human tissues prevent the phenotypic expression of a homoplasmic mt-tRNA point mutation. These findings extend previous observations on aaRSs therapeutic effects in yeast and human.
Assuntos
Cardiomiopatia Hipertrófica/enzimologia , Cardiomiopatia Hipertrófica/genética , Isoleucina-tRNA Ligase/metabolismo , Penetrância , Mutação Puntual , RNA de Transferência de Isoleucina/genética , Adolescente , Sequência de Bases , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Humanos , Isoleucina-tRNA Ligase/genética , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Dados de Sequência Molecular , RNA de Transferência de Isoleucina/metabolismoRESUMO
Accumulating senescent cells within tissues contribute to the progression of aging and age-related diseases. Botanical extracts, rich in phytoconstituents, present a useful resource for discovering therapies that could target senescence and thus improve healthspan. Here, we show that daily oral administration of a standardized extract of Salvia haenkei (Haenkenium (HK)) extended lifespan and healthspan of naturally aged mice. HK treatment inhibited age-induced inflammation, fibrosis and senescence markers across several tissues, as well as increased muscle strength and fur thickness compared with age-matched controls. We also found that HK treatment reduced acutely induced senescence by the chemotherapeutic agent doxorubicin, using p16LUC reporter mice. We profiled the constituent components of HK by mass spectrometry, and identified luteolin-the most concentrated flavonoid in HK-as a senomorphic compound. Mechanistically, by performing surface plasmon resonance and in situ proximity ligation assay, we found that luteolin disrupted the p16-CDK6 interaction. This work demonstrates that administration of HK promotes longevity in mice, possibly by modulating cellular senescence and by disrupting the p16-CDK6 interaction.
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Cellular senescence can exert dual effects in tumors, either suppressing or promoting tumor progression. The senescence-associated secretory phenotype (SASP), released by senescent cells, plays a crucial role in this dichotomy. Consequently, the clinical challenge lies in developing therapies that safely enhance senescence in cancer, favoring tumor-suppressive SASP factors over tumor-promoting ones. Here, we identify the retinoic-acid-receptor (RAR) agonist adapalene as an effective pro-senescence compound in prostate cancer (PCa). Reactivation of RARs triggers a robust senescence response and a tumor-suppressive SASP. In preclinical mouse models of PCa, the combination of adapalene and docetaxel promotes a tumor-suppressive SASP that enhances natural killer (NK) cell-mediated tumor clearance more effectively than either agent alone. This approach increases the efficacy of the allogenic infusion of human NK cells in mice injected with human PCa cells, suggesting an alternative therapeutic strategy to stimulate the anti-tumor immune response in "immunologically cold" tumors.
Assuntos
Senescência Celular , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Neoplasias da Próstata/tratamento farmacológico , Receptores do Ácido Retinoico , Células Matadoras Naturais , AdapalenoRESUMO
Platinum agents, which include cisplatin, oxaliplatin and carboplatin, are chemotherapeutic drugs that represent the first-line treatment for different types of solid tumors, such as ovarian, head and neck, testicular, and bladder cancers. Their beneficial effect is limited by the onset of drug resistance and severe toxicities, involving mainly ototoxicity, neurotoxicity and nephrotoxicity. Recent studies highlight the supplementation of herbal products, vitamins and minerals with antioxidant properties to prevent and protect from side effects. In particular, the introduction of nutraceuticals associated with chemotherapy has improved the patients' quality of life. However, if from one side, complementary and alternative medicine ameliorates chemotherapeutics-induced toxicities, from the other side, it is important to take into consideration the possible interference with drug metabolism. This review aims to consider the current literature focusing on clinical trials that report an association between nutraceutical supplementation and platinum- based chemotherapy to prevent toxicities, highlighting both beneficial and side effects.
Assuntos
Antineoplásicos , Humanos , Antineoplásicos/uso terapêutico , Platina , Qualidade de Vida , Cisplatino/uso terapêutico , Cisplatino/efeitos adversos , Carboplatina/uso terapêutico , Suplementos NutricionaisRESUMO
Osteosarcoma is considered the most common bone tumor affecting children and young adults. The standard of care is chemotherapy; however, the onset of drug resistance still jeopardizes osteosarcoma patients, thus making it necessary to conduct a thorough investigation of the possible mechanisms behind this phenomenon. In the last decades, metabolic rewiring of cancer cells has been proposed as a cause of chemotherapy resistance. Our aim was to compare the mitochondrial phenotype of sensitive osteosarcoma cells (HOS and MG-63) versus their clones when continuously exposed to doxorubicin (resistant cells) and identify alterations exploitable for pharmacological approaches to overcome chemotherapy resistance. Compared with sensitive cells, doxorubicin-resistant clones showed sustained viability with less oxygen-dependent metabolisms, and significantly reduced mitochondrial membrane potential, mitochondrial mass, and ROS production. In addition, we found reduced expression of TFAM gene generally associated with mitochondrial biogenesis. Finally, combined treatment of resistant osteosarcoma cells with doxorubicin and quercetin, a known inducer of mitochondrial biogenesis, re-sensitizes the doxorubicin effect in resistant cells. Despite further investigations being needed, these results pave the way for the use of mitochondrial inducers as a promising strategy to re-sensitize doxorubicin cytotoxicity in patients who do not respond to therapy or reduce doxorubicin side effects.
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BACKGROUND: Irritable bowel syndrome (IBS) and Inflammatory bowel disease (IBD) are pathological conditions that severely hamper the quality of life of patients. Especially in pediatric and adolescent patients, the use of Complementary and alternative medicine is an appealing approach as an adjuvant for the management of symptoms, limiting the detrimental effect of the conventional therapy. In this work, we tested the effect of Enterokind Junior (EntJ), a mix of two probiotic strains Lactobacillus reuteri DSM 25175 and Lactobacillus acidophilus DSM 24936, Matricaria Chamomilla, and vitamins, in in vitro model of intestinal inflammation. Caco-2 cells were subjected to LPS treatment or THP-1 cells stimulated with LPS treatment, as paradigms of inflammatory conditions. METHODS: The effect of the probiotic formulation was evaluated by measuring Caco-2 monolayer's Transepithelial Electrical resistance (TEER) and paracellular permeability alterations, tight junction proteins expression and localization by confocal microscopy, and release of pro-inflammatory cytokines (TNF-α and IL-8) by ELISA assay. RESULTS: Results demonstrated that upon impairment of intestinal parameters induced by inflammatory stimuli, the combination of probiotic was able to prevent TEER decrease and paracellular permeability alterations and to maintain the tight junction expression and localization. Moreover, the release of proinflammatory cytokines induced by inflammation was reduced by EntJ treatment. CONCLUSIONS: This work, in line with previous observations, supports a protective role of Lactobacillus reuteri DSM 25175, Lactobacillus acidophilus DSM 24936 and the other components in the maintenance of a healthy gut, holding up the use of this combination as an adjuvant for irritable bowel syndrome-related symptoms management.
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BACKGROUND: Vitamin D (VD) has been implicated in several diseases, including colorectal cancer (CRC). This study aimed to determine whether there is an association between VD levels and time-to-outcome in stage III CRC patients through a systematic review and meta-analysis. METHODS: The study adhered to the PRISMA 2020 statement. Articles were searched in PubMed/MEDLINE and Scopus/ELSEVIER. Four articles were selected, with the primary objective of providing a pooled estimate of the risk of death specifically in stage III CRC patients based on pre-operative VD levels. Study heterogeneity and publication bias were analyzed using Tau2 statistics and funnel plots. RESULTS: The selected studies showed significant heterogeneity regarding time-to-outcome, technical assessments, and serum VD concentration measures. The pooled analysis of 2628 and 2024 patients revealed a 38% and 13% increase in the risk of death (HR: 1.38, 95% CI: 0.71-2.71) and recurrence (HR: 1.13; 95% CI: 0.84-1.53), respectively, for random-effects models among patients with lower levels of VD. CONCLUSIONS: Our findings suggest that a low concentration of VD has a significant negative impact on time-to-outcome in stage III CRC.
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Tumor cells promote the recruitment of immunosuppressive neutrophils, a subset of myeloid cells driving immune suppression, tumor proliferation, and treatment resistance. Physiologically, neutrophils are known to have a short half-life. Here, we report the identification of a subset of neutrophils that have upregulated expression of cellular senescence markers and persist in the tumor microenvironment. Senescent-like neutrophils express the triggering receptor expressed on myeloid cells 2 (TREM2) and are more immunosuppressive and tumor-promoting than canonical immunosuppressive neutrophils. Genetic and pharmacological elimination of senescent-like neutrophils decreases tumor progression in different mouse models of prostate cancer. Mechanistically, we have found that apolipoprotein E (APOE) secreted by prostate tumor cells binds TREM2 on neutrophils, promoting their senescence. APOE and TREM2 expression increases in prostate cancers and correlates with poor prognosis. Collectively, these results reveal an alternative mechanism of tumor immune evasion and support the development of immune senolytics targeting senescent-like neutrophils for cancer therapy.