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1.
Mol Biol Rep ; 51(1): 661, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758505

RESUMEN

SCN5A mutations have been reported to cause various cardiomyopathies in humans. Most of the SCN5A mutations causes loss of function and thereby, alters the overall cellular function. Therefore, to understand the loss of SCN5A function in cardiomyocytes, we have knocked down the SCN5A gene (SCN5A-KD) in H9c2 cells and explored the cell phenotype and molecular behaviors in the presence and absence of isoproterenol (ISO), an adrenergic receptor agonist that induces cardiac hypertrophy. Expression of several genes related to hypertrophy, inflammation, fibrosis, and energy metabolism pathways were evaluated. It was found that the mRNA expression of hypertrophy-related gene, brain (B-type) natriuretic peptide (BNP) was significantly increased in SCN5A-KD cells as compared to 'control' H9c2 cells. There was a further increase in the mRNA expressions of BNP and ßMHC in SCN5A-KD cells after ISO treatment compared to their respective controls. Pro-inflammatory cytokine, tumor necrosis factor-alpha expression was significantly increased in 'SCN5A-KD' H9c2 cells. Further, metabolism-related genes like glucose transporter type 4, cluster of differentiation 36, peroxisome proliferator-activated receptor alpha, and peroxisome proliferator-activated receptor-gamma were significantly elevated in the SCN5A-KD cells as compared to the control cells. Upregulation of these metabolic genes is associated with increased ATP production. The study revealed that SCN5A knock-down causes alteration of gene expression related to cardiac hypertrophy, inflammation, and energy metabolism pathways, which may promote cardiac remodelling and cardiomyopathy.


Asunto(s)
Cardiomegalia , Isoproterenol , Canal de Sodio Activado por Voltaje NAV1.5 , Canal de Sodio Activado por Voltaje NAV1.5/genética , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo , Cardiomegalia/genética , Cardiomegalia/metabolismo , Ratas , Línea Celular , Isoproterenol/farmacología , Miocitos Cardíacos/metabolismo , Péptido Natriurético Encefálico/genética , Péptido Natriurético Encefálico/metabolismo , Animales , Técnicas de Silenciamiento del Gen , Humanos , Mioblastos Cardíacos/metabolismo , Metabolismo Energético/genética , Regulación de la Expresión Génica/genética
2.
Nat Chem Biol ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509349

RESUMEN

Angiogenic programming in the vascular endothelium is a tightly regulated process for maintaining tissue homeostasis and is activated in tissue injury and the tumor microenvironment. The metabolic basis of how gas signaling molecules regulate angiogenesis is elusive. Here, we report that hypoxic upregulation of ·NO in endothelial cells reprograms the transsulfuration pathway to increase biogenesis of hydrogen sulfide (H2S), a proangiogenic metabolite. However, decreased H2S oxidation due to sulfide quinone oxidoreductase (SQOR) deficiency synergizes with hypoxia, inducing a reductive shift and limiting endothelial proliferation that is attenuated by dissipation of the mitochondrial NADH pool. Tumor xenografts in whole-body (WBCreSqorfl/fl) and endothelial-specific (VE-cadherinCre-ERT2Sqorfl/fl) Sqor-knockout mice exhibit lower mass and angiogenesis than control mice. WBCreSqorfl/fl mice also exhibit decreased muscle angiogenesis following femoral artery ligation compared to control mice. Collectively, our data reveal the molecular intersections between H2S, O2 and ·NO metabolism and identify SQOR inhibition as a metabolic vulnerability for endothelial cell proliferation and neovascularization.

3.
Cureus ; 16(2): e53590, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38449939

RESUMEN

According to the literature, transverse sinus hypoplasia is not a normal variant and has a serious potential effect on cerebral blood flow. We are presenting a rare case of chronic headache due to severe hypoplasia of the left transverse and sigmoidal sinus. A 12-year-old female girl was admitted with a complaint of gradual progressive severe headache, throbbing in nature, confined to a bitemporal and frontal region in the last 4-5 months. Headache is not associated with fever, vomiting, photophobia, or vision problems. The child had no history of recurrent running nose, refractory vision, ear discharge, head trauma, exanthemata rash, or any drug history. On examination, the child was conscious and oriented. Vital signs are normal. The child was neurologically normal and had no focal signs. Other systemic examinations were normal. Based on History and examination, differential diagnosis was made, like Pseudo tumor cerebri, migraine, deep vein sinus thrombosis, and functional and Posterior fossa tumor. The child had normal routine investigations like complete blood count, electrolyte, and D-dimer. The fundoscopy was normal. In MRI, brain hypoplasia of the left transverse and sinusoidal sinus was suspected and confirmed by MRI venography. Thus, for any patient in an emergency with a chronic headache without focal signs and normal fundoscopy, one deferential should be considered for transverse and sigmoid sinus hypoplasia.

4.
Mol Nutr Food Res ; 68(6): e2300688, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342595

RESUMEN

The human gut microbiota regulates estrogen metabolism through the "estrobolome," the collection of bacterial genes that encode enzymes like ß-glucuronidases and ß-glucosidases. These enzymes deconjugate and reactivate estrogen, influencing circulating levels. The estrobolome mediates the enterohepatic circulation and bioavailability of estrogen. Alterations in gut microbiota composition and estrobolome function have been associated with estrogen-related diseases like breast cancer, enometrial cancer, and polycystic ovarian syndrome (PCOS). This is likely due to dysregulated estrogen signaling partly contributed by the microbial impacts on estrogen metabolism. Dietary phytoestrogens also undergo bacterial metabolism into active metabolites like equol, which binds estrogen receptors and exhibits higher estrogenic potency than its precursor daidzein. However, the ability to produce equol varies across populations, depending on the presence of specific gut microbes. Characterizing the estrobolome and equol-producing genes across populations can provide microbiome-based biomarkers. Further research is needed to investigate specific components of the estrobolome, phytoestrogen-microbiota interactions, and mechanisms linking dysbiosis to estrogen-related pathology. However, current evidence suggests that the gut microbiota is an integral regulator of estrogen status with clinical relevance to women's health and hormonal disorders.


Asunto(s)
Neoplasias de la Mama , Microbioma Gastrointestinal , Femenino , Humanos , Fitoestrógenos , Microbioma Gastrointestinal/fisiología , Equol/metabolismo , Estrógenos/metabolismo , Neoplasias de la Mama/metabolismo
6.
Braz J Microbiol ; 54(4): 2671-2687, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37688688

RESUMEN

Lyngbya from fresh and marine water produces an array of pharmaceutically bioactive therapeutic compounds. However, Lyngbya from agricultural soil is still poorly investigated. Hence, in this study, the bioactive potential of different Lyngbya spp. extract was explored. Intracellular petroleum ether extract of L. hieronymusii K81 showed the highest phenolic content (626.22 ± 0.65 µg GAEs g-1 FW), while intracellular ethyl acetate extract of L. aestuarii K97 (74.02 ± 0.002 mg QEs g-1 FW) showed highest flavonoid content. Highest free radical scavenging activity in terms of ABTS•+ was recorded in intracellular methanolic extract of Lyngbya sp. K5 (97.85 ± 0.068%), followed by L. wollei K80 (97.22 ± 0.059%) while highest DPPH• radical scavenging activity observed by intracellular acetone extract of Lyngbya sp. K5 (54.59 ± 0.165%). All the extracts also showed variable degrees of antifungal activities against Fusarium udum, F. oxysporum ciceris, Colletotrichum capsici, and Rhizoctonia solani. Further, extract of L. wollei K80 and L. aestuarii K97 showed potential anticancer activities against MCF7 (breast cancer) cell lines. GC-MS analyses of intracellular methanolic extract of L. wollei K80 showed the dominance of PUFAs with 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z) as the most abundant bioactive compound. On the other hand, the extracellular ethyl acetate extract of L. aestuarii K97 was rich in alkanes and alkenes with 1-hexyl-2-nitrocyclohexane as the most predominant compound. Extracts of Lyngbya spp. rich in novel secondary metabolites such as PUFAs, alkanes, and alkenes can be further explored as an alternative and low-cost antioxidant and potential apoptogens for cancer therapy.


Asunto(s)
Antifúngicos , Antioxidantes , Antioxidantes/farmacología , Antioxidantes/análisis , Antifúngicos/farmacología , Lyngbya , Extractos Vegetales/farmacología , Alcanos , Alquenos
7.
J Coll Physicians Surg Pak ; 33(6): 625-632, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37300256

RESUMEN

OBJECTIVE: To compile a comprehensive national cancer registry report of Pakistan by merging and analysing cancer registration data received from major functional cancer registries in various parts of Pakistan. STUDY DESIGN: Observational study. Place and Duration of the Study: Health Research Institute (HRI), National Institutes of Health (NIH), Islamabad, from 2015-2019. METHODOLOGY: Data from major cancer registries which included 'Punjab Cancer Registry (PCR), 'Karachi Cancer Registry (KCR)', 'Pakistan Atomic Energy Commission (PAEC) Cancer Registry', Armed Forces Institute of Pathology (AFIP) Cancer Registry, Nishtar Medical University Hospital Multan (NMH), and Shifa International Hospital, Islamabad (SIH) registries were pooled, cleared, and analysed at HRI. RESULTS: A total of 269,707 cancer cases were analysed. Gender-wise 46.7% were males and 53.61% were females. As per province-wise distribution, 45.13% of cases were from Punjab, 26.83% from Sindh, 16.46% from Khyber Pakhtunkhwa (KP), and 3.52% from Baluchistan. Both genders combined, 'breast cancer' 57633 (21.4%) was the most common cancer. In males, the top-5 cancers in order of frequency/percenatages were 'oral' 14477 (11.6%), 'liver' 8398 (6.73%), colorectal 8024 (6.43%), 'lung' 7547 (6.05%) and 'prostate' 7322 (5.87% cancers). In females, causes of the top-5-cancers included 'breast' 56250 (38.8%), 'ovary' 8823 (6.09%), 'oral' 7195 (4.97%), 'cervix' 6043 (4.17%), and 'colorectal' 4860 (3.36%) cancers. In children 'Leukemia' 1626 (14.50%) and in adolescents 'Bone' 880 (14%) were the leading malignancies. CONCLUSION: Breast cancer is the most common cancer in females touching epidemic proportions while 'oral cancer' which is the leading cancer in males ranks third in frequency in females. Like 'oral cancer' which shows a strong correlation with chewing, other common cancers in Pakistan including liver cancer, lung cancer, and cervical cancer are also largely preventable as showed a strong correlation with hepatitis B and C, smoking, and high-risk human papillomavirus. KEY WORDS: National Cancer Registry, Health Research Institute - NIH, Islamabad, Pakistan.


Asunto(s)
Neoplasias de la Mama , Neoplasias Pulmonares , Neoplasias de la Boca , Neoplasias , Niño , Adolescente , Humanos , Masculino , Femenino , Pakistán/epidemiología , Neoplasias/epidemiología , Neoplasias/patología , Neoplasias de la Mama/epidemiología , Sistema de Registros , Incidencia
8.
Bioorg Chem ; 138: 106660, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37320914

RESUMEN

Cancer is spreading worldwide and is one of the leading causes of death. The use of existing chemotherapeutic agents is frequently limited due to side effects. As a result, it is critical to investigate new agents for cancer treatment. In this context, we developed an electrochemical method for the synthesis of a series of thiol-linked pyrimidine derivatives (3a-3p) and explored their anti-cancer potential. The biological profile of the synthesized compounds was evaluated against breast (MDAMB-231 and MCF-7) and colorectal (HCT-116) cancer cell lines. 3b and 3d emerged to be the most potent agents, with IC50 values ranging between 0.98 to 2.45 µM. Target delineation studies followed by secondary anticancer parameters were evaluated for most potent compounds, 3b and 3d. The analysis revealed compounds possess DNA intercalation potential and selective inhibition towards human topoisomerase (hTopo1). The analysis was further corroborated by DNA binding studies and in silico-based molecular modeling studies that validated the intercalating binding mode between the compounds and the DNA.


Asunto(s)
Antineoplásicos , Uracilo , Humanos , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular , Técnicas de Química Sintética , ADN , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Uracilo/farmacología
9.
bioRxiv ; 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36993187

RESUMEN

Angiogenic programming in the vascular endothelium is a tightly regulated process to maintain tissue homeostasis and is activated in tissue injury and the tumor microenvironment. The metabolic basis of how gas signaling molecules regulate angiogenesis is elusive. Herein, we report that hypoxic upregulation of NO synthesis in endothelial cells reprograms the transsulfuration pathway and increases H 2 S biogenesis. Furthermore, H 2 S oxidation by mitochondrial sulfide quinone oxidoreductase (SQOR) rather than downstream persulfides, synergizes with hypoxia to induce a reductive shift, limiting endothelial cell proliferation that is attenuated by dissipation of the mitochondrial NADH pool. Tumor xenografts in whole-body WB Cre SQOR fl/fl knockout mice exhibit lower mass and reduced angiogenesis compared to SQOR fl/fl controls. WB Cre SQOR fl/fl mice also exhibit reduced muscle angiogenesis following femoral artery ligation, compared to controls. Collectively, our data reveal the molecular intersections between H 2 S, O 2 and NO metabolism and identify SQOR inhibition as a metabolic vulnerability for endothelial cell proliferation and neovascularization. Highlights: Hypoxic induction of •NO in endothelial cells inhibits CBS and switches CTH reaction specificity Hypoxic interruption of the canonical transsulfuration pathway promotes H 2 S synthesis Synergizing with hypoxia, SQOR deficiency induces a reductive shift in the ETC and restricts proliferationSQOR KO mice exhibit lower neovascularization in tumor xenograft and hind limb ischemia models.

10.
Antioxid Redox Signal ; 38(1-3): 57-67, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35651282

RESUMEN

Significance: A burgeoning literature has attributed varied physiological effects to hydrogen sulfide (H2S), which is a product of eukaryotic sulfur amino acid metabolism. Protein persulfidation represents a major focus of studies elucidating the mechanism underlying H2S signaling. On the contrary, the capacity of H2S to induce reductive stress by targeting the electron transport chain (ETC) and signal by reprogramming redox metabolism has only recently begun to be elucidated. Recent Advances: In contrast to the nonspecific reaction of H2S with oxidized cysteines to form protein persulfides, its inhibition of complex IV represents a specific mechanism of action. Studies on the dual impact of H2S as an ETC substrate and an inhibitor have led to the exciting discovery of ETC plasticity and the use of fumarate as a terminal electron acceptor. H2S oxidation combined with complex IV targeting generates mitochondrial reductive stress, which is signaled through the metabolic network, leading to increased aerobic glycolysis, glutamine-dependent reductive carboxylation, and lipogenesis. Critical Issues: Insights into H2S-induced metabolic reprogramming are ushering in a paradigm shift for understanding the mechanism of its cellular action. It will be critical to reevaluate the physiological effects of H2S, for example, cytoprotection against ischemia-reperfusion injury, through the framework of metabolic reprogramming and ETC remodeling by H2S. Future Directions: The metabolic ramifications of H2S in other cellular compartments, for example, the endoplasmic reticulum and the nucleus, as well as the intersections between hypoxia and H2S signaling are important future directions that merit elucidation. Antioxid. Redox Signal. 38, 57-67.


Asunto(s)
Sulfuro de Hidrógeno , Sulfuro de Hidrógeno/metabolismo , Transporte de Electrón , Transducción de Señal , Oxidación-Reducción , Cisteína/metabolismo
11.
Cell Metab ; 35(1): 134-149.e6, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36528023

RESUMEN

Effective therapies are lacking for patients with advanced colorectal cancer (CRC). The CRC tumor microenvironment has elevated metabolic waste products due to altered metabolism and proximity to the microbiota. The role of metabolite waste in tumor development, progression, and treatment resistance is unclear. We generated an autochthonous metastatic mouse model of CRC and used unbiased multi-omic analyses to reveal a robust accumulation of tumoral ammonia. The high ammonia levels induce T cell metabolic reprogramming, increase exhaustion, and decrease proliferation. CRC patients have increased serum ammonia, and the ammonia-related gene signature correlates with altered T cell response, adverse patient outcomes, and lack of response to immune checkpoint blockade. We demonstrate that enhancing ammonia clearance reactivates T cells, decreases tumor growth, and extends survival. Moreover, decreasing tumor-associated ammonia enhances anti-PD-L1 efficacy. These findings indicate that enhancing ammonia detoxification can reactivate T cells, highlighting a new approach to enhance the efficacy of immunotherapies.


Asunto(s)
Amoníaco , Neoplasias Colorrectales , Animales , Ratones , Agotamiento de Células T , Linfocitos T , Neoplasias Colorrectales/patología , Inmunoterapia , Microambiente Tumoral
12.
Sci Rep ; 12(1): 22405, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36575290

RESUMEN

Mechanical and corrosion properties of welded duplex stainless steel (DSS) structures are of paramount consideration in many engineering applications. The current research investigates the mechanical properties and corrosion integrity of duplex stainless-steel weldment in a simulated 3.5% NaCl environment using specially developed novel electrodes without the addition of alloying elements to the flux samples. Two different types of fluxes having basicity indexes of 2.40 and 0.40 were used to coat E1 and E2 electrodes respectively for DSS plate welding. The thermal stability of the formulated flux was evaluated using thermogravimetric analysis. The chemical composition, using optical emission spectroscopy, and the mechanical and corrosion properties of the welded joints were evaluated as per different ASTM standards. X-ray diffraction was used to find out the phases present in the DSS welded joints while a scanning electron equipped with EDS was used for microstructural examination of the weldments. The ultimate tensile strength of welded joints made using the E1 electrode was in the range of 715-732 MPa and that of the E2 electrode was found to be 606-687 MPa. The hardness was increased with increased welding current from 90 to 110 A. The welded joint with E1 electrode coated with basic flux has better mechanical properties. The steel structure in 3.5% NaCl environment possesses substantial resistance to corrosion attack. This validates the performance of the welded joints made by the newly developed electrode. The results are discussed on the basis of the depletion of alloying elements such as Cr and Mo observed from the weldments with the coated electrodes E1 and E2 as well as precipitation of the Cr2N in the welded joints made by E1 and E2 electrodes.

13.
JBJS Case Connect ; 12(3)2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35852168

RESUMEN

CASE: A 40-year-old man presented with spontaneous, atraumatic right groin pain and inability to bear weight secondary to an isolated avulsion of the right lesser trochanter. Magnetic resonance imaging of the affected hip was suggestive of an infection, and a computed tomography-guided biopsy was remarkable for Mycobacterium tuberculosis, which was successfully managed with antitubercular therapy and activity modification. CONCLUSION: Although an isolated spontaneous avulsion of the lesser trochanter is typically pathognomonic for malignancy, an infectious etiology, such as tuberculosis, should also be considered in the differential diagnosis.


Asunto(s)
Neoplasias , Tuberculosis , Adulto , Diagnóstico Diferencial , Fémur , Humanos , Masculino , Tomografía Computarizada por Rayos X
14.
Biosci Rep ; 42(7)2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35737296

RESUMEN

Heterotrimeric G-proteins interact with various upstream and downstream effectors to regulate various aspects of plant growth and development. G-protein effectors have been recently reported in Arabidopsis thaliana; however, less information is available from polyploid crop species having complex networks of G-protein components. Regulator of G-protein signaling (RGS) is a well-characterized GTPase accelerating protein, which plays an important role in the regulation of the G-protein cycle in plants. In the present study, four homologs encoding RGS proteins were isolated from the allotetraploid Brassica juncea, a globally important oilseed, vegetable, and condiment crop. The B. juncea RGS proteins were grouped into distinct BjuRGS1 and BjuRGS2 orthologous clades, and the expression of BjuRGS1 homologs was predominantly higher than BjuRGS2 homologs across the tested tissue types of B. juncea. Utilizing B. juncea Y2H library screening, a total of 30 nonredundant interacting proteins with the RGS-domain of the highly expressed BjuA.RGS1 was identified. Gene ontology analysis indicated that these effectors exerted various molecular, cellular, and physiological functions. Many of them were known to regulate cell wall metabolism (BjuEXP6, Bju-α-MAN, BjuPGU4, BjuRMS3) and phosphorylation-mediated cell signaling (BjuMEK4, BjuDGK3, and BjuKinase). Furthermore, transcript analysis indicated that the identified interacting proteins have a coexpression pattern with the BjuRGS homologs. These findings increase our knowledge about the novel targets of G-protein components from a globally cultivated Brassica crop and provide an important resource for developing a plant G-protein interactome network.


Asunto(s)
Arabidopsis , Proteínas RGS , Arabidopsis/genética , Pared Celular/genética , Proteínas de Unión al GTP , Humanos , Planta de la Mostaza/genética , Planta de la Mostaza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo
15.
ACS Chem Neurosci ; 13(10): 1517-1525, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35500217

RESUMEN

S-Nitrosylation is a reversible post-translational modification that regulates protein function involving the covalent attachment of the nitric oxide (NO) moiety to sulfhydryl residues of the protein. It is an important regulator in the cell signaling process under physiological conditions. However, the release of an excess amount of NO due to dysregulated NOS machinery causes aberrant S-nitrosylation of proteins, which affects protein folding, localization, and activity. Here, we have shown that OTUB1, a deubiquitinating enzyme, undergoes S-nitrosylation under redox stress conditions in vivo and in vitro. Previously, we have shown that OTUB1 forms an amyloid-like structure that promotes phosphorylation of α-synuclein and neuronal toxicity. However, the mechanistic insight into OTUB1 aggregation remains elusive. Here, we identified that OTUB1 undergoes S-nitrosylation in SH-SY5Y neuroblastoma cells under rotenone-induced stress, as well as excitotoxic conditions, and in rotenone-treated mouse brains. The in vitro S-nitrosylation of OTUB1 followed by mass-spectrometry analysis has identified cysteine-23 and cysteine-91 as S-nitrosylation sites. S-Nitrosylated OTUB1 (SNO-OTUB1) diminished its catalytic activity, impaired its native structure, promoted amyloid-like aggregation, and compromised its binding with Ubc13. Thus, our results demonstrated that nitrosylation of OTUB1 might play a crucial role in regulating the ubiquitin signaling and Parkinson's disease pathology.


Asunto(s)
Cisteína Endopeptidasas , Enfermedad de Parkinson , Enzimas Ubiquitina-Conjugadoras , Amiloide/metabolismo , Animales , Cisteína/metabolismo , Cisteína Endopeptidasas/metabolismo , Ratones , Óxido Nítrico/metabolismo , Enfermedad de Parkinson/metabolismo , Procesamiento Proteico-Postraduccional , Rotenona/farmacología , Enzimas Ubiquitina-Conjugadoras/metabolismo
16.
Trends Biochem Sci ; 47(8): 689-698, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35397924

RESUMEN

The electron transport chain (ETC) is a major currency converter that exchanges the chemical energy of fuel oxidation to proton motive force and, subsequently, ATP generation, using O2 as a terminal electron acceptor. Discussed herein, two new studies reveal that the mammalian ETC is forked. Hypoxia or H2S exposure promotes the use of fumarate as an alternate terminal electron acceptor. The fumarate/succinate and CoQH2/CoQ redox couples are nearly iso-potential, revealing that complex II is poised for facile reverse electron transfer, which is sensitive to CoQH2 and fumarate concentrations. The gas regulators, H2S and •NO, modulate O2 affinity and/or inhibit the electron transfer rate at complex IV. Their induction under hypoxia suggests a mechanism for how traffic at the ETC fork can be regulated.


Asunto(s)
Electrones , Fumaratos , Animales , Transporte de Electrón , Hipoxia , Mamíferos , Oxidación-Reducción
17.
J Orthop Surg Res ; 17(1): 76, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35123515

RESUMEN

BACKGROUND: Disorders involving the musculoskeletal system are often identified with short stature and a range of orthopedic problems. The clinical and genetic heterogeneity of these diseases along with several characteristic overlaps makes definitive diagnosis difficult for clinicians. Hence, using molecular testing in addition to conventional tests becomes essential for appropriate diagnosis and management. METHODS: Comprehensive clinical examination, detailed pretest and posttest counseling, molecular diagnosis with next-generation sequencing (NGS), genotype-phenotype correlation and Sanger sequencing for targeted variant analysis. RESULTS: This manuscript reports a molecular spectrum of variants in 34 orthopedic cases referred to a single genetic unit attached to a tertiary care hospital. The diagnostic yield of NGS-based tests coupled with genetic counseling and segregation analysis was 79% which included 7 novel variants. In about 53% (i.e. 18/34 cases), molecular testing outcome was actionable since 8 of the 18 underwent prenatal diagnosis, as they were either in their early gestation or had planned a pregnancy subsequent to molecular testing, while ten cases were premaritally/prenatally counseled for the families to take informed decisions as they were in the reproductive age. CONCLUSIONS: The report highlights the importance of NGS-based tests even in a low resource setting as it helps patients, families and healthcare providers in reducing the economic, social and emotional burden of these disorders.


Asunto(s)
Asesoramiento Genético , Pruebas Genéticas , Enfermedades Musculoesqueléticas/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Asociación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/diagnóstico , Sistema Musculoesquelético , Embarazo , Adulto Joven
18.
J Biol Chem ; 297(2): 100950, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34252456

RESUMEN

Mammalian cells synthesize H2S from sulfur-containing amino acids and are also exposed to exogenous sources of this signaling molecule, notably from gut microbes. As an inhibitor of complex IV in the electron transport chain, H2S can have a profound impact on metabolism, suggesting the hypothesis that metabolic reprogramming is a primary mechanism by which H2S signals. In this study, we report that H2S increases lipogenesis in many cell types, using carbon derived from glutamine rather than from glucose. H2S-stimulated lipid synthesis is sensitive to the mitochondrial NAD(P)H pools and is enabled by reductive carboxylation of α-ketoglutarate. Lipidomics analysis revealed that H2S elicits time-dependent changes across several lipid classes, e.g., upregulating triglycerides while downregulating phosphatidylcholine. Direct analysis of triglyceride concentration revealed that H2S induces a net increase in the size of this lipid pool. These results provide a mechanistic framework for understanding the effects of H2S on increasing lipid droplets in adipocytes and population studies that have pointed to a positive correlation between cysteine (a substrate for H2S synthesis) and fat mass.


Asunto(s)
Glutamina , Sulfuro de Hidrógeno , NAD , Metabolismo Energético , Lipogénesis , Mitocondrias/metabolismo , Transducción de Señal
19.
ACS Chem Neurosci ; 12(11): 1919-1930, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34015214

RESUMEN

α-Synuclein is a natively unfolded protein and its deposition in the Lewy body and Lewy neurites in the substantia nigra region of the brain is linked to Parkinson's disease (PD). The molecular mechanisms of α-synuclein aggregation and its clearance have not been well understood. Until now, several strategies have been designed to inhibit α-synuclein aggregation and related cytotoxicity. Polyphenols, small molecules, synthetic peptides, and peptide-derived molecules have been considered as potential candidates that inhibit α-synuclein oligomerization and its fibrillation, and a few of them are in clinical trials. We have identified a polyphenolic compound ellagic acid (EA) that inhibits α-synuclein aggregation. Our results demonstrated that EA inhibits primary nucleation, seeded aggregation, and membrane-induced aggregation. The cytotoxicity of α-synuclein oligomers and fibers treated with EA has been investigated and we found that EA treated oligomers and fibrils showed reduced cytotoxicity. Additionally, we also observed inhibition of membrane binding of α-synuclein by EA in SH-SY5Y cells. In conclusion, the present study suggests that small molecules such as ellagic acid have anti-amyloidogenic properties and may have therapeutic potential for Parkinson's disease and other proteinopathies.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Ácido Elágico/farmacología , Humanos , Cuerpos de Lewy/metabolismo , Sustancia Negra/metabolismo , alfa-Sinucleína/metabolismo
20.
J Clin Invest ; 131(12)2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33914705

RESUMEN

Hypoxia is a hallmark of solid tumors that promotes cell growth, survival, and metastasis and confers resistance to chemo and radiotherapies. Hypoxic responses are largely mediated by the transcription factors hypoxia-inducible factor 1α (HIF-1α) and HIF-2α. Our work demonstrates that HIF-2α is essential for colorectal cancer (CRC) progression. However, targeting hypoxic cells is difficult, and tumors rapidly acquire resistance to inhibitors of HIF-2α. To overcome this limitation, we performed a small molecule screen to identify HIF-2α-dependent vulnerabilities. Several known ferroptosis activators and dimethyl fumarate (DMF), a cell-permeable mitochondrial metabolite derivative, led to selective synthetic lethality in HIF-2α-expressing tumor enteroids. Our work demonstrated that HIF-2α integrated 2 independent forms of cell death via regulation of cellular iron and oxidation. First, activation of HIF-2α upregulated lipid and iron regulatory genes in CRC cells and colon tumors in mice and led to a ferroptosis-susceptible cell state. Second, via an iron-dependent, lipid peroxidation-independent pathway, HIF-2α activation potentiated ROS via irreversible cysteine oxidation and enhanced cell death. Inhibition or knockdown of HIF-2α decreased ROS and resistance to oxidative cell death in vitro and in vivo. Our results demonstrated a mechanistic vulnerability in cancer cells that were dependent on HIF-2α that can be leveraged for CRC treatment.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica , Hierro/metabolismo , Proteínas de Neoplasias/biosíntesis , Especies Reactivas de Oxígeno/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Muerte Celular/genética , Hipoxia de la Célula/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Células HCT116 , Células HT29 , Humanos , Ratones , Ratones Transgénicos , Proteínas de Neoplasias/genética , Oxidación-Reducción
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