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Abstract Introduction: A recent revision of the generic classification of the Trochilidae based on DNA sequences revealed many inconsistencies with the current generic classification, largely based on plumage characters subject to homoplasy, especially in the Trochilini, the largest tribe. A thorough generic reorganization brought the classification into accord with the phylogeny, but due to lack of genetic data, two species remained unclassified. One of these was the Mangrove Hummingbird, "Amazilia" boucardi, endemic to Costa Rica and included in the IUCN red list of threatened species. Objective: To obtain molecular evidence to clarify the generic relationships of "A." boucardi. Methods: We isolated DNA from tissues of this species and amplified 4 nuclear and 4 mitochondrial fragments and compared these with homologous fragments from 56 species in the Trochilini, constructing phylogenetic trees with maximum likelihood and Bayesian methods. Results: Our phylogenetic analyses confirmed the placement of boucardi in the Trochilini and definitely excluded it from Amazilia but placed it with high confidence in the genus Chrysuronia Bonaparte, 1850, within which its closest relative is C. coeruleogularis, which also inhabits mangroves. Conclusions: Our genetic data based on nuclear and mitochondrial regions clearly indicate the relationship of A. boucardi and L. coeruleogularis. Moreover, it is also supported by their habitat distribution in the mangroves of the Pacific coast of Costa Rica and Western Panama. Therefore, we suggested to exclude A. boucardi as "incertae sedis".
Resumen Introducción: Una revisión reciente de la clasificación de la familia Trochilidae con base en secuencias de ADN demostró muchas incongruencias con la clasificación genérica previa, que había sido hecho con base en caracteres del plumaje muy sujetos a homoplasia, especialmente en la tribu más grande, Trochillini. Una reorganización de los géneros logró llevar su clasificación genérica a la concordancia con la filogenia, pero debido a la ausencia de datos genéticos, dos especies permanecieron sin clasificar. Una de estas fue el colibrí de manglar Amazilia boucardi, una especie endémica de Costa Rica, considerada como amenazada en la lista roja de la UICN. Objetivo: Obtener evidencia molecular para esclarecer las relaciones genéricas de A. boucardi. Métodos: Se aisló ADN de tejidos de esta especie y se amplificaron 4 fragmentos de ADN del núcleo y 5 de la mitocondria, y se compararon con fragmentos homólogos de 56 especies en la tribu Trochillini, generando árboles filogenéticos con métodos de máxima verosimilitud y bayesiano. Resultados: Los análisis filogénticos obtenidos confirmaron la ubicación de boucardi en Trochilini y definitivamente la excluyó del género Amazilia, pero la ubicó con un alto grado de confianza en el género Chrysuronia Bonaparte, 1850, dentro los cuales su pariente más cercano es C. coeruleogularis, que también habita manglares. Conclusiones: Nuestros datos genéticos basados en regiones nucleares y mitocondriales indican claramente la relación entre A. boucardi and L. coeruleogularis. Es más, lo anterior se sustenta por su distribución en los manglares de la costa Pacífica de Costa Rica y oeste de Panamá. Por lo tanto, sugerimos excluir a A. boucardi como "incertae sedis".
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Animais , Aves/classificação , DNA/análise , Filogenia , Costa Rica , Genes MitocondriaisRESUMO
Mitochondrial function relies on the coordinated expression of mitochondrial and nuclear genes, exhibiting remarkable resilience despite high mitochondrial mutation rates. The nuclear compensation mechanism suggests deleterious mitochondrial alleles drive compensatory nuclear mutations to preserve mito-nuclear compatibility. However, prevalence and factors conditioning this phenomenon remain debated due to its conflicting evidence. Here, we investigate how mito-nuclear incompatibilities impact substitutions in a model for species radiation. Mating success depends on genetic compatibility (nuclear DNA) and spatial proximity. Populations evolve from partially compatible mito-nuclear states, simulating mitochondrial DNA (mtDNA) introgression. Mutations do not confer advantages nor disadvantages, but individual fecundity declines with increasing incompatibilities, selecting for mito-nuclear coordination. We find that selection for mito-nuclear compatibility affects each genome differently based on their initial state. In compatible gene pairs, selection reduces substitutions in both genomes, while in incompatible nuclear genes, it consistently promotes compensation, facilitated by more mismatches. Interestingly, high mitochondrial mutation rates can reduce nuclear compensation by increasing mtDNA rectification, while substitutions in initially compatible nuclear gene are boosted. Finally, the presence of incompatibilities accelerates species radiation, but equilibrium richness is not directly correlated to substitution rates, revealing the complex dynamics triggered by mitochondrial introgression and mito-nuclear coevolution. Our study provides a perspective on nuclear compensation and the role of mito-nuclear incompatibilities in speciation by exploring extreme scenarios and identifying trends that empirical data alone cannot reveal. We emphasize the challenges in detecting these dynamics and propose analyzing specific genomic signatures could shed light on this evolutionary process.
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Núcleo Celular , DNA Mitocondrial , Núcleo Celular/genética , Núcleo Celular/metabolismo , DNA Mitocondrial/genética , Mutação , Modelos Genéticos , Evolução Molecular , Mitocôndrias/genética , Mitocôndrias/metabolismo , Animais , Seleção Genética , Evolução Biológica , Taxa de MutaçãoRESUMO
INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) may be familial or sporadic, and twin studies have revealed that even sporadic forms have a significant genetic component. Variants in 55 nuclear genes have been associated with ALS and although mitochondrial dysfunction is observed in ALS, variants in mitochondrial genomes (mitogenomes) have not yet been tested for association with ALS. The aim of this study was to determine whether mitogenome variants are associated with ALS. METHODS: We conducted a genome-wide association study (GWAS) in mitogenomes of 1965 ALS patients and 2547 controls. RESULTS: We identified 51 mitogenome variants with p values <10-7, of which 13 had odds ratios (ORs) >1, in genes RNR1, ND1, CO1, CO3, ND5, ND6, and CYB, while 38 variants had OR <1 in genes RNR1, RNA2, ND1, ND2, CO2, ATP8, ATP6, CO3, ND3, ND4, ND5, ND6, and CYB. The frequencies of haplogroups H, U, and L, the most frequent in our ALS data set, were the same in different onset sites (bulbar, limb, spinal, and axial). Also, intra-haplogroup GWAS revealed unique ALS-associated variants in haplogroups L and U. DISCUSSION: Our study shows that mitogenome single nucleotide variants (SNVs) are associated with ALS and suggests that these SNVs could be included in routine genetic testing for ALS and that mitochondrial replacement therapy has the potential to serve as a basis for ALS treatment.
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Esclerose Lateral Amiotrófica , Genoma Mitocondrial , Estudo de Associação Genômica Ampla , Humanos , Esclerose Lateral Amiotrófica/genética , Genoma Mitocondrial/genética , Masculino , Feminino , Pessoa de Meia-Idade , Haplótipos , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença/genética , Idoso , Variação Genética/genéticaRESUMO
Introduction: It has been demonstrated the dysregulation of the cardiac endocannabinoid system in cardiovascular diseases. Thus, the modulation of this system through the administration of phytocannabinoids present in medicinal cannabis oil (CO) emerges as a promising therapeutic approach. Furthermore, phytocannabinoids exhibit potent antioxidant properties, making them highly desirable in the treatment of cardiac pathologies, such as hypertension-induced cardiac hypertrophy (CH). Objective: To evaluate the effect of CO treatment on hypertrophy and mitochondrial status in spontaneously hypertensive rat (SHR) hearts. Methods: Three-month-old male SHR were randomly assigned to CO or olive oil (vehicle) oral treatment for 1 month. We evaluated cardiac mass and histology, mitochondrial dynamics, membrane potential, area and density, myocardial reactive oxygen species (ROS) production, superoxide dismutase (SOD), and citrate synthase (CS) activity and expression. Data are presented as mean ± SEM (n) and compared by t-test, or two-way ANOVA and Bonferroni post hoc test were used as appropriate. p < 0.05 was considered statistically significant. Results: CH was reduced by CO treatment, as indicated by the left ventricular weight/tibia length ratio, left ventricular mass index, myocyte cross-sectional area, and left ventricle collagen volume fraction. The ejection fraction was preserved in the CO-treated group despite the persistence of elevated systolic blood pressure and the reduction in CH. Mitochondrial membrane potential was improved and mitochondrial biogenesis, dynamics, area, and density were all increased by treatment. Moreover, the activity and expression of the CS were enhanced by treatment, whereas ROS production was decreased and the antioxidant activity of SOD increased by CO administration. Conclusion: Based on the mentioned results, we propose that 1-month oral treatment with CO is effective to reduce hypertrophy, improve the mitochondrial pool and increase the antioxidant capacity in SHR hearts.
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OBJECTIVE: Obesity represents a significant global health challenge characterized by chronic low-grade inflammation and metabolic dysregulation. The hypothalamus, a key regulator of energy homeostasis, is particularly susceptible to obesity's deleterious effects. This study investigated the role of the immunoproteasome, a specialized proteasomal complex implicated in inflammation and cellular homeostasis, during metabolic diseases. METHODS: The levels of the immunoproteasome ß5i subunit were analyzed by immunostaining, western blotting, and proteasome activity assay in mice fed with either a high-fat diet (HFD) or a regular diet (CHOW). We also characterized the impact of autophagy inhibition on the levels of the immunoproteasome ß5i subunit and the activation of the AKT pathway. Finally, through confocal microscopy, we analyzed the contribution of ß5i subunit inhibition on mitochondrial function by flow cytometry and mitophagy assay. RESULTS: Using an HFD-fed obese mouse model, we found increased immunoproteasome levels in hypothalamic POMC neurons. Furthermore, we observed that palmitic acid (PA), a major component of saturated fats found in HFD, increased the levels of the ß5i subunit of the immunoproteasome in hypothalamic neuronal cells. Notably, the increase in immunoproteasome expression was associated with decreased autophagy, a critical cellular process in maintaining homeostasis and suppressing inflammation. Functionally, PA disrupted the insulin-glucose axis, leading to reduced AKT phosphorylation and increased intracellular glucose levels in response to insulin due to the upregulation of the immunoproteasome. Mechanistically, we identified that the protein PTEN, a key regulator of insulin signaling, was reduced in an immunoproteasome-dependent manner. To further investigate the potential therapeutic implications of these findings, we used ONX-0914, a specific immunoproteasome inhibitor. We demonstrated that this inhibitor prevents PA-induced insulin-glucose axis imbalance. Given the interplay between mitochondrial dysfunction and metabolic disturbances, we explored the impact of ONX-0914 on mitochondrial function. Notably, ONX-0914 preserved mitochondrial membrane potential and attenuated mitochondrial ROS production in the presence of PA. Moreover, we found that ONX-0914 reduced mitophagy in the presence of PA. CONCLUSIONS: Our findings strongly support the pathogenic involvement of the immunoproteasome in hypothalamic neurons in the context of HFD-induced obesity and metabolic disturbances. Targeting the immunoproteasome highlights a promising therapeutic strategy to mitigate the detrimental effects of obesity on the insulin-glucose axis and cellular homeostasis. This study provides valuable insights into the mechanisms driving obesity-related metabolic diseases and offers potential avenues for developing novel therapeutic interventions.
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Dieta Hiperlipídica , Hipotálamo , Camundongos Endogâmicos C57BL , Neurônios , Obesidade , Complexo de Endopeptidases do Proteassoma , Animais , Dieta Hiperlipídica/efeitos adversos , Camundongos , Hipotálamo/metabolismo , Obesidade/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Masculino , Doenças Metabólicas/metabolismo , Doenças Metabólicas/etiologia , OligopeptídeosRESUMO
Renal iron overload is a common complication of diabetes that leads to oxidative stress and mitochondrial dysfunction in the kidneys. This study investigated the effects of iron chelation using deferiprone on mitochondrial dysfunction and oxidative stress in the renal cortex of a murine model of type 2 diabetes. Diabetic rats were treated with deferiprone (50 mg/kg BW) for 16 weeks. Our results show that iron chelation with deferiprone significantly increased the nuclear accumulation of Nrf2, a transcription factor that regulates the expression of antioxidant enzymes. This led to enhanced antioxidant capacity, reduced production of reactive oxygen species, and improved mitochondrial bioenergetic function in diabetic rats. However, chronic iron chelation led to altered mitochondrial respiration and increased oxidative stress in non-diabetic rats. In conclusion, our findings suggest that iron chelation with deferiprone protects mitochondrial bioenergetics and mitigates oxidative stress in the renal cortex, involving the NRF2 pathway in type 2 diabetes.
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Deferiprona , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Córtex Renal , Fator 2 Relacionado a NF-E2 , Animais , Masculino , Camundongos , Ratos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Deferiprona/farmacologia , Deferiprona/uso terapêutico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Quelantes de Ferro/farmacologia , Córtex Renal/metabolismo , Córtex Renal/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Mitofusins (Mfn1 and Mfn2) are the mitochondrial outer-membrane fusion proteins in mammals and belong to the dynamin superfamily of multidomain GTPases. Recent structural studies of truncated variants lacking alpha helical transmembrane domains suggested that Mfns dimerize to promote the approximation and the fusion of the mitochondrial outer membranes upon the hydrolysis of guanine 5'-triphosphate disodium salt (GTP). However, next to the presence of GTP, the fusion activity seems to require multiple regulatory factors that control the dynamics and kinetics of mitochondrial fusion through the formation of Mfn1-Mfn2 heterodimers. Here, we purified and reconstituted the full-length murine Mfn2 protein into giant unilamellar vesicles (GUVs) with different lipid compositions. The incubation with GTP resulted in the fusion of Mfn2-GUVs. High-speed video-microscopy showed that the Mfn2-dependent membrane fusion pathway progressed through a zipper mechanism where the formation and growth of an adhesion patch eventually led to the formation of a membrane opening at the rim of the septum. The presence of physiological concentration (up to 30 mol%) of dioleoyl-phosphatidylethanolamine (DOPE) was shown to be a requisite to observe GTP-induced Mfn2-dependent fusion. Our observations show that Mfn2 alone can promote the fusion of micron-sized DOPE-enriched vesicles without the requirement of regulatory cofactors, such as membrane curvature, or the assistance of other proteins.
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GTP Fosfo-Hidrolases , Fusão de Membrana , Animais , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Camundongos , Fusão de Membrana/fisiologia , Lipossomas Unilamelares/metabolismo , Lipossomas Unilamelares/química , Guanosina Trifosfato/metabolismo , Fosfatidiletanolaminas/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Mitocôndrias/metabolismoRESUMO
Dengue virus (DENV) infection is known to affect host cell metabolism, but the molecular players involved are still poorly known. Using a proteomics approach, we identified six DENV proteins associated with mitochondria isolated from infected hepatocytes, and most of the peptides identified were from NS3. We also found an at least twofold decrease of several electron transport system (ETS) host proteins. Thus, we investigated whether NS3 could modulate the ETS function by incubating recombinant DENV NS3 constructs in mitochondria isolated from mouse liver. We found that NS3pro (NS3 protease domain), but not the correspondent catalytically inactive mutant (NS3proS135A), impairs complex I (CI)-dependent NADH:ubiquinone oxidoreductase activity, but not the activities of complexes II, III, IV, or V. Accordingly, using high-resolution respirometry, we found that both NS3pro and full-length NS3 decrease the respiratory rates associated with malate/pyruvate oxidation in mitochondria. The NS3-induced impairment in mitochondrial respiration occurs without altering either leak respiration or mitochondria's capacity to maintain membrane potential, suggesting that NS3 does not deeply affect mitochondrial integrity. Remarkably, CI activity is also inhibited in DENV-infected cells, supporting that the NS3 effects observed in isolated mitochondria may be relevant in the context of the infection. Finally, in silico analyses revealed the presence of potential NS3 cleavage sites in 17 subunits of mouse CI and 16 subunits of human CI, most of them located on the CI surface, suggesting that CI is prone to undergo proteolysis by NS3. Our findings suggest that DENV NS3 can modulate mitochondrial bioenergetics by directly affecting CI function. IMPORTANCE: Dengue virus (DENV) infection is a major public health problem worldwide, affecting about 400 million people yearly. Despite its importance, many molecular aspects of dengue pathogenesis remain poorly known. For several years, our group has been investigating DENV-induced metabolic alterations in the host cells, focusing on the bioenergetics of mitochondrial respiration. The results of the present study reveal that the DENV non-structural protein 3 (NS3) is found in the mitochondria of infected cells, impairing mitochondrial respiration by directly targeting one of the components of the electron transport system, the respiratory complex I (CI). NS3 acts as the viral protease during the DENV replication cycle, and its proteolytic activity seems necessary for inhibiting CI function. Our findings uncover new nuances of DENV-induced metabolic alterations, highlighting NS3 as an important player in the modulation of mitochondria function during infection.
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Vírus da Dengue , Complexo I de Transporte de Elétrons , Mitocôndrias , Proteínas não Estruturais Virais , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Animais , Vírus da Dengue/fisiologia , Vírus da Dengue/genética , Camundongos , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/genética , Humanos , Mitocôndrias/metabolismo , Hepatócitos/virologia , Hepatócitos/metabolismo , Serina Endopeptidases/metabolismo , Serina Endopeptidases/genética , Dengue/virologia , Dengue/metabolismo , Respiração Celular , Proteômica , Proteases ViraisRESUMO
Background: In the marine environment, knowledge of biodiversity remains incomplete for many taxa, requiring assessments to understand and monitor biodiversity loss. Environmental DNA (eDNA) metabarcoding is a powerful tool for monitoring marine biodiversity, as it enables several taxa to be characterised simultaneously in a single sample. However, the data generated by environmental DNA metabarcoding are often not easily reusable. Implementing FAIR principles and standards for eDNA-derived data can facilitate data-sharing within the scientific community. New information: This study focuses on the detection of marine vertebrate biodiversity using eDNA metabarcoding on the leeward coast of Guadeloupe, a known hotspot for marine biodiversity in the French West Indies. Occurrences and DNA-derived data are shared here using DarwinCore standards combined with MIMARKS standards.
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Mitochondrial dysfunction is a key driver of cardiovascular disease (CVD) in metabolic syndrome and diabetes. This dysfunction promotes the production of reactive oxygen species (ROS), which cause oxidative stress and inflammation. Angiotensin II, the main mediator of the renin-angiotensin-aldosterone system, also contributes to CVD by promoting ROS production. Reduced activity of sirtuins (SIRTs), a family of proteins that regulate cellular metabolism, also worsens oxidative stress. Reduction of energy production by mitochondria is a common feature of all metabolic disorders. High SIRT levels and 5' adenosine monophosphate-activated protein kinase signaling stimulate hypoxia-inducible factor 1 beta, which promotes ketosis. Ketosis, in turn, increases autophagy and mitophagy, processes that clear cells of debris and protect against damage. Sodium-glucose cotransporter-2 inhibitors (SGLT2i), a class of drugs used to treat type 2 diabetes, have a beneficial effect on these mechanisms. Randomized clinical trials have shown that SGLT2i improves cardiac function and reduces the rate of cardiovascular and renal events. SGLT2i also increase mitochondrial efficiency, reduce oxidative stress and inflammation, and strengthen tissues. These findings suggest that SGLT2i hold great potential for the treatment of CVD. Furthermore, they are proposed as anti-aging drugs; however, rigorous research is needed to validate these preliminary findings.
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While cytostatic chemotherapy targeting DNA is known to induce genotoxicity, leading to cell cycle arrest and cytokine secretion, the impact of these drugs on fibroblast-epithelial cancer cell communication and metabolism remains understudied. Our research focused on human breast fibroblast RMF-621 exposed to nonlethal concentrations of cisplatin and doxorubicin, revealing reduced proliferation, diminished basal and maximal mitochondrial respirations, heightened mitochondrial ROS and lactate production, and elevated MCT4 protein levels. Interestingly, RMF-621 cells enhanced glucose uptake, promoting lactate export. Breast cancer cells MCF-7 exposed to conditioned media (CM) from drug-treated stromal RMF-621 cells increased MCT1 protein levels, lactate-driven mitochondrial respiration, and a significantly high mitochondrial spare capacity for lactate. These changes occurred alongside altered mitochondrial respiration, mitochondrial membrane potential, and superoxide levels. Furthermore, CM with doxorubicin and cisplatin increased migratory capacity in MCF-7 cells, which was inhibited by MCT1 (BAY-8002), glutamate dehydrogenase (EGCG), mitochondrial pyruvate carrier (UK5099), and complex I (rotenone) inhibitors. A similar behavior was observed in T47-D and ZR-75-1 breast cancer cells. This suggests that CM induces metabolic rewiring involving elevated lactate uptake to sustain mitochondrial bioenergetics during migration. Treatment with the mitochondrial-targeting antioxidant mitoTEMPO in RMF-621 and the addition of an anti-CCL2 antibody in the CM prevented the promigratory MCF-7 phenotype. Similar effects were observed in THP1 monocyte cells, where CM increased monocyte recruitment. We propose that nonlethal concentrations of DNA-damaging drugs induce changes in the cellular environment favoring a promalignant state dependent on mitochondrial bioenergetics.
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The RNA-binding PUF proteins are post-transcriptional regulators found throughout the eukaryotic domain. In Trypanosoma cruzi, ten Puf genes termed Puf1 to Puf10 have been identified. Considering that the control of gene expression in this parasite is mainly at the post-transcriptional level, we characterized the PUF3 protein by knocking out and overexpressing the gene in T. cruzi epimastigotes and studied different genetic and biological features. The RNA-seq analyses in both genotypes showed significant changes in the number of regulated transcripts compared with wild-type parasites. Thus, the number of differentially expressed genes in the knockout (ΔTcPuf3) and the overexpressor (pTEXTcPuf3) were 238 and 187, respectively. In the knockout, a more significant proportion of genes was negatively regulated (166 out of 238). In contrast, in the overexpressor, positively regulated genes were predominant (149 out of 170). Additionally, when we predicted the subcellular location of the differentially expressed genes, the results revealed an important representation of nuclear genes encoding mitochondrial proteins. Therefore, we determined whether overexpression or knockout of TcPuf3 could lead to changes in both mitochondrial structure and cellular respiration. When mitochondria from ΔTcPuf3 and pTEXTcPuf3 parasites were analyzed by transmission electron microscopy (TEM), it was observed that the overexpressor had an abnormal mitochondrial morphology, evidenced by swelling. The results associated with cellular respiration showed that both the ΔTcPuf3 and pTEXTcPuf3 had a lower efficiency in routine respiration and the electron transport system capacity. Likewise, the mitochondria from overexpressing parasites showed a slight hyperpolarization. Additionally, several biological features, depending on the function of the mitochondria, were altered, such as growth, cell division, metacyclogenesis, ROS production, and response to benznidazole. In conclusion, our results suggest that although PUF3 is not an essential protein in T. cruzi, it influences mitochondrial transcripts, affecting mitochondrial morphology and function.
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Leishmaniasis is a disease caused by protozoa Leishmania spp., considered as a significant and urgent public health problem mainly in developing countries. In the absence of an effective vaccine, the treatment of infected people is one of the most commonly prophylactic measures used to control this disease. However, the therapeutic arsenal is reduced to a few drugs, with serious side effects and variability in efficacy. Attempting to this problem, in this work, a series of benzothiazole derivatives was synthetized and assayed against promastigotes and intracellular amastigotes of L. amazonensis, as well as the toxicity on macrophages. In addition, studies about the mechanism of action were also performed. Among the synthesized molecules, the substitution at position 4 of the aromatic ring appears to be critical for activity. The best compound exhibited IC50 values of 28.86 and 7.70 µM, against promastigotes and amastigotes of L. amazonensis, respectively, being more active than miltefosine, used as reference drug. The in silico analysis of physicochemical and pharmacokinetic (ADMET) properties of this compound suggested a good profile of oral bioavailability and safety. In conclusion, the strategy of using benzothiazole nucleous in the search for new antileishmanial agents was advantageous and preliminar data provide information about the mechanism of action as well as in silico parameters suggest a good profile for preclinical studies.
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Antiprotozoários , Benzotiazóis , Hidrazonas , Leishmania , Benzotiazóis/química , Benzotiazóis/farmacologia , Benzotiazóis/síntese química , Antiprotozoários/farmacologia , Antiprotozoários/química , Antiprotozoários/síntese química , Animais , Hidrazonas/química , Hidrazonas/farmacologia , Hidrazonas/síntese química , Camundongos , Leishmania/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Relação Estrutura-Atividade , HumanosRESUMO
In vitro embryo production is a widely applied technique that allows the expansion of genetics and accelerated breeding programs. However, in cattle, this technique still needs improvement in order to reach quality and pregnancy rates comparable to in vivo-derived embryos. One of the limitations of this technique is related to in vitro maturation, where a heterogeneous population of oocytes is harvested from follicles and cultured in vitro in the presence of gonadotropic hormones to induce maturation. As a result, oocytes with different degrees of competence are obtained, resulting in a decrease in the quality and quantity of embryos obtained. A novel system based on the use of cyclic adenosine monophosphate (cAMP) modulators was developed to enhance bovine oocyte competence, although controversial results were obtained depending on the in vitro embryo production (IVP) system used in each laboratory. Thus, in the present work, we employed a reported cAMP protocol named Simulated Physiological Oocyte Maturation (SPOM) under our IVP system and analysed its effect on cytoplasmic maturation by measuring levels of stress-related genes and evaluating the activity and distribution of mitochondria as a marker for cytoplasmic maturation Moreover, we studied the effect of the cAMP treatment on nuclear maturation, cleavage, and blastocyst formation. Finally, we assessed the embryo quality by determining the hatching rates, total cell number per blastocyst, cryopreservation tolerance, and embryo implantation. We found that maturing oocytes in the presence of cAMP modulators did not affect nuclear maturation, although they changed the dynamic pattern of mitochondrial activity along maturation. Additionally, we found that oocytes subjected to cAMP modulators significantly improved blastocyst formation (15.5% vs. 22.2%, p < 0.05). Blastocysts derived from cAMP-treated oocytes did not improve cryopreservation tolerance but showed an increased hatching rate, a higher total cell number per blastocyst and, when transferred to hormonally synchronised recipients, produced pregnancies. These results reflect that the use of cAMP modulators during IVM results in competent oocytes that, after fertilisation, can develop in more blastocysts with a better quality than standard IVM conditions.
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BACKGROUND: Mitochondrial dysfunction occurs in monocytes during obesity and contributes to a low-grade inflammatory state; therefore, maintaining good mitochondrial conditions is a key aspect of maintaining health. Dietary interventions are primary strategies for treating obesity, but little is known about their impact on monocyte bioenergetics. Thus, the aim of this study was to evaluate the effects of calorie restriction (CR), intermittent fasting (IF), a ketogenic diet (KD), and an ad libitum habitual diet (AL) on mitochondrial function in monocytes and its modulation by the gut microbiota. METHODS AND FINDINGS: A randomized controlled clinical trial was conducted in which individuals with obesity were assigned to one of the 4 groups for 1 month. Subsequently, the subjects received rifaximin and continued with the assigned diet for another month. The oxygen consumption rate (OCR) was evaluated in isolated monocytes, as was the gut microbiota composition in feces and anthropometric and biochemical parameters. Forty-four subjects completed the study, and those who underwent CR, IF and KD interventions had an increase in the maximal respiration OCR (p = 0.025, n2p = 0.159 [0.05, 0.27] 95% confidence interval) in monocytes compared to that in the AL group. The improvement in mitochondrial function was associated with a decrease in monocyte dependence on glycolysis after the IF and KD interventions. Together, diet and rifaximin increased the gut microbiota diversity in the IF and KD groups (p = 0.0001), enriched the abundance of Phascolarctobacterium faecium (p = 0.019) in the CR group and Ruminococcus bromii (p = 0.020) in the CR and KD groups, and reduced the abundance of lipopolysaccharide (LPS)-producing bacteria after CR, IF and KD interventions compared to the AL group at the end of the study according to ANCOVA with covariate adjustment. Spearman's correlation between the variables measured highlighted LPS as a potential modulator of the observed effects. In line with this findings, serum LPS and intracellular signaling in monocytes decreased with the three interventions (CR, p = 0.002; IF, p = 0.001; and KD, p = 0.001) compared to those in the AL group at the end of the study. CONCLUSIONS: We conclude that these dietary interventions positively regulate mitochondrial bioenergetic health and improve the metabolic profile of monocytes in individuals with obesity via modulation of the gut microbiota. Moreover, the evaluation of mitochondrial function in monocytes could be used as an indicator of metabolic and inflammatory status, with potential applications in future clinical trials. TRIAL REGISTRATION: This trial was registered with ClinicalTrials.gov (NCT05200468).
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Restrição Calórica , Dieta Cetogênica , Microbioma Gastrointestinal , Mitocôndrias , Monócitos , Obesidade , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Restrição Calórica/métodos , Dieta Cetogênica/métodos , Jejum Intermitente , Lipopolissacarídeos , Mitocôndrias/metabolismo , Monócitos/metabolismo , Obesidade/dietoterapia , Obesidade/metabolismo , Consumo de Oxigênio , Transdução de SinaisRESUMO
Methylphenidate (MPH) is a central nervous system stimulant drug and a first order prescription in the treatment of Attention Deficit Hyperactivity Disorder (ADHD). Although MPH biochemistry in neurodevelopment is not completely understood, studies showed it alters energy metabolism in rat brains. ADHD prevalence during neurodevelopment is related to males and the investigation has been mainly done in these subjects, therefore, little is known about MPH action in females and, consequently, about sexual dimorphism. In the present study we evaluated markers of mitochondrial dynamics (DRP1 and MFN2, fission and fusion, respectively), biogenesis (mtTFA) and bioenergetics (respiratory chain complexes) in prefrontal cortex of male and female juvenile rats submitted to exposure to MPH to better understand MPH effect during postnatal neurodevelopment. ATP and oxidative stress levels were also evaluated. Wistar rats received intraperitoneal injection of MPH (2.0 mg/kg) or control (saline), once a day, from 15th to 45th day of age. Results showed that MPH increased DRP1 and decreased MFN2, as well as increased mtTFA in prefrontal cortex of male rats. In female, MPH decreased NRF1 and increased Parkin, which are mitochondrial regulatory proteins. Respiratory chain complexes (complex I, SDH, complexes III and IV), ATP production and oxidative stress parameters were altered and shown to be sex-dependent. Taken together, results suggest that chronic MPH exposure at an early age in healthy animals changes mitochondrial dynamics, biogenesis and bioenergetics differently depending on the sex of the subjects.
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Estimulantes do Sistema Nervoso Central , Dinaminas , Metabolismo Energético , Metilfenidato , Dinâmica Mitocondrial , Estresse Oxidativo , Córtex Pré-Frontal , Ratos Wistar , Animais , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Metilfenidato/farmacologia , Masculino , Dinâmica Mitocondrial/efeitos dos fármacos , Feminino , Estimulantes do Sistema Nervoso Central/farmacologia , Metabolismo Energético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Dinaminas/metabolismo , Ratos , Caracteres Sexuais , Trifosfato de Adenosina/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Ubiquitina-Proteína LigasesRESUMO
BACKGROUND: Growing evidence has shown that mitochondrial dysfunction is part of the pathogenesis of Parkinson's disease (PD). However, the role of mitochondrial DNA (mtDNA) variants on PD onset is unclear. OBJECTIVES: The present study aims to evaluate the effect of mtDNA variants and haplogroups on risk of developing PD. METHODS: Systematic review and meta-analysis of studies investigating associations between PD and mtDNA variants and haplogroups. RESULTS: A total of 33 studies were eligible from 957 screened studies. Among 13,640 people with PD and 22,588 control individuals, the association with PD was consistently explored in 13 mtDNA variants in 10 genes and 19 macrohaplogroups. Four mtDNA variants were associated with PD: m.4336C (odds ratio [OR] = 2.99; 95 % confidence interval [CI] = 1.79-5.02), m.7028T (OR = 0.80; 95 % CI = 0.70-0.91), m.10398G (OR = 0.92; 95 % CI = 0.85-0.98), and m.13368A (OR = 0.74; 95 % CI = 0.56-0.98). Four mtDNA macrohaplogroups were associated with PD: R (OR = 2.25; 95 % CI = 1.92-2.65), F (OR = 1.18; 95 % CI = 1.01-1.38), H (OR = 1.12; 95 % CI = 1.06-1.18), and B (OR = 0.77; 95 % CI = 0.65-0.92). CONCLUSIONS: Despite most studies may be underpowered by the underrepresentation of people without dominant European- and Asian-ancestry, low use of next-generation sequencing for genotyping and small sample sizes, the identification of mtDNA variants and macrohaplogroups associated with PD strengthens the link between the disease and mitochondrial dysfunction and mtDNA genomic instability.
Assuntos
DNA Mitocondrial , Haplótipos , Doença de Parkinson , Doença de Parkinson/genética , Humanos , DNA Mitocondrial/genética , Predisposição Genética para Doença , Variação Genética/genéticaRESUMO
Obesity is a worldwide multifactorial disease caused by an imbalance in energy metabolism, increasing adiposity, weight gain, and promoting related diseases such as diabetes, cardiovascular diseases, neurodegeneration, and cancer. Recent findings have reported that metabolic stress related to obesity induces a mitochondrial stress response called mitochondrial unfolded protein response (UPRmt), a quality control pathway that occurs in a nuclear DNA-mitochondria crosstalk, causing transduction of chaperones and proteases under stress conditions. The duality of UPRmt signaling, with both beneficial and detrimental effects, acts in different contexts depending on the tissue, cell type, and physiological states, affecting the mitochondrial function and efficiency and the metabolism homeostasis during obesity, which remains not fully clarified. Therefore, this review discusses the most recent findings regarding UPRmt signaling during obesity, bringing an overview of UPRmt across different metabolic tissues.
Assuntos
Mitocôndrias , Obesidade , Resposta a Proteínas não Dobradas , Humanos , Obesidade/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Mitocôndrias/metabolismo , Animais , Transdução de Sinais , Metabolismo Energético/fisiologiaRESUMO
The herbicide triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) is already considered an environmental problem due to damage caused by incorrect disposal, leaching, and aerial dispersion, which may pose risks to the environment and human health. Studies have evaluated metabolism, absorption, excretion, and active transport but there is no clear information about its mode of action (MoA) and its cytotoxic action potential remains unknown. In this context, mitochondria have been used to assess the toxicity of xenobiotics, for this reason, to identify the toxic mechanism of triclopyr, hepatic mitochondria from Wistar rats were exposed in vitro to different concentrations of triclopyr (0.5-500 µM). There was neither formation/accumulation of reactive oxygen and nitrogen species, nor lipid peroxidation or changes in the mitochondrial antioxidant system, in addition to proper functioning of oxidative phosphorylation and ATP production. Changes were found in NAD(P)H oxidation, membrane potential dissipation and mitochondrial calcium gradient. These results demonstrate that mitochondria suffer damage related to their bioenergetics and redox status but not to their structure when exposed to concentrations of triclopyr considered higher than those described as found in the environment so far.HighlightsTriclopyr has a low mitochondrial uncoupling potential.The damage caused to the bioenergetics and redox state of the mitochondria is related to concentrations considered higher than those found in the environment.Even at high concentrations, triclopyr was not able to change the structure of the organelle after exposure.Oxidative phosphorylation and ATP production were not impaired after exposure.NAD(P)H oxidation resulted in potential membrane dissipation and mitochondrial calcium gradient dissipation.Triclopyr does not have RONS-forming properties, as well as it does not peroxide membrane lipids, it preserves membrane sulfhydryl groups and maintains the normality of the GSH/GSSG ratio.
RESUMO
Atherosclerosis (AS) has become the leading cause of cardiovascular disease worldwide. Our previous study had observed that Nippostrongylus brasiliensis (Nb) infection or its derived products could inhibit AS development by inducing an anti-inflammatory response. We performed a metabolic analysis to screen Nb-derived metabolites with anti-inflammation activity and evaluated the AS-prevention effect. We observed that the metabolite uridine had higher expression levels in mice infected with the Nb and ES (excretory-secretory) products and could be selected as a key metabolite. ES and uridine interventions could reduce the pro-inflammatory responses and increase the anti-inflammatory responses in vitro and in vivo. The apolipoprotein E gene knockout (ApoE-/-) mice were fed with a high-fat diet for the AS modeling. Following the in vivo intervention, ES products or uridine significantly reduced serum and liver lipid levels, alleviated the formation of atherosclerosis, and reduced the pro-inflammatory responses in serum or plaques, while the anti-inflammatory responses showed opposite trends. After blocking with 5-HD (5-hydroxydecanoate sodium) in vitro, the mRNA levels of M2 markers were significantly reduced. When blocked with 5-HD in vivo, the degree of atherosclerosis was worsened, the pro-inflammatory responses were increased compared to the uridine group, while the anti-inflammatory responses decreased accordingly. Uridine, a key metabolite from Nippostrongylus brasiliensis, showed anti-inflammatory and anti-atherosclerotic effects in vitro and in vivo, which depend on the activation of the mitochondrial ATP-sensitive potassium channel.