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1.
EMBO Rep ; 25(8): 3627-3650, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38982191

RESUMO

Skeletal muscle regeneration involves a signaling network that regulates the proliferation, differentiation, and fusion of muscle precursor cells to injured myofibers. IRE1α, one of the arms of the unfolded protein response, regulates cellular proteostasis in response to ER stress. Here, we demonstrate that inducible deletion of IRE1α in satellite cells of mice impairs skeletal muscle regeneration through inhibiting myoblast fusion. Knockdown of IRE1α or its downstream target, X-box protein 1 (XBP1), also inhibits myoblast fusion during myogenesis. Transcriptome analysis revealed that knockdown of IRE1α or XBP1 dysregulates the gene expression of molecules involved in myoblast fusion. The IRE1α-XBP1 axis mediates the gene expression of multiple profusion molecules, including myomaker (Mymk). Spliced XBP1 (sXBP1) transcription factor binds to the promoter of Mymk gene during myogenesis. Overexpression of myomaker in IRE1α-knockdown cultures rescues fusion defects. Inducible deletion of IRE1α in satellite cells also inhibits myoblast fusion and myofiber hypertrophy in response to functional overload. Collectively, our study demonstrates that IRE1α promotes myoblast fusion through sXBP1-mediated up-regulation of the gene expression of multiple profusion molecules, including myomaker.


Assuntos
Fusão Celular , Endorribonucleases , Desenvolvimento Muscular , Músculo Esquelético , Mioblastos , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Proteína 1 de Ligação a X-Box , Animais , Proteína 1 de Ligação a X-Box/metabolismo , Proteína 1 de Ligação a X-Box/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Camundongos , Mioblastos/metabolismo , Mioblastos/citologia , Músculo Esquelético/metabolismo , Músculo Esquelético/citologia , Desenvolvimento Muscular/genética , Endorribonucleases/metabolismo , Endorribonucleases/genética , Células Satélites de Músculo Esquelético/metabolismo , Regeneração/genética , Diferenciação Celular/genética , Regulação da Expressão Gênica , Proteínas de Membrana , Proteínas Musculares
2.
Bioessays ; 45(4): e2300003, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36789559

RESUMO

Maintenance of skeletal muscle mass and strength throughout life is crucial for heathy living and longevity. Several signaling pathways have been implicated in the regulation of skeletal muscle mass in adults. TGF-ß-activated kinase 1 (TAK1) is a key protein, which coordinates the activation of multiple signaling pathways. Recently, it was discovered that TAK1 is essential for the maintenance of skeletal muscle mass and myofiber hypertrophy following mechanical overload. Forced activation of TAK1 in skeletal muscle causes hypertrophy and attenuates denervation-induced muscle atrophy. TAK1-mediated signaling in skeletal muscle promotes protein synthesis, redox homeostasis, mitochondrial health, and integrity of neuromuscular junctions. In this article, we have reviewed the role and potential mechanisms through which TAK1 regulates skeletal muscle mass and growth. We have also proposed future areas of research that could be instrumental in exploring TAK1 as therapeutic target for improving muscle mass in various catabolic conditions and diseases.


Assuntos
MAP Quinase Quinase Quinases , Músculo Esquelético , Humanos , Hipertrofia , MAP Quinase Quinase Quinases/metabolismo , Transdução de Sinais/fisiologia
3.
Am J Physiol Renal Physiol ; 327(1): F137-F145, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38779756

RESUMO

Polymyxins are a last-resort treatment option for multidrug-resistant gram-negative bacterial infections, but they are associated with nephrotoxicity. Gelofusine was previously shown to reduce polymyxin-associated kidney injury in an animal model. However, the mechanism(s) of renal protection has not been fully elucidated. Here, we report the use of a cell culture model to provide insights into the mechanisms of renal protection. Murine epithelial proximal tubular cells were exposed to polymyxin B. Cell viability, lactate dehydrogenase (LDH) release, polymyxin B uptake, mitochondrial superoxide production, nuclear morphology, and apoptosis activation were evaluated with or without concomitant gelofusine. A megalin knockout cell line was used as an uptake inhibition control. Methionine was included in selected experiments as an antioxidant control. A polymyxin B concentration-dependent reduction in cell viability was observed. Increased viability was observed in megalin knockout cells following comparable polymyxin B exposures. Compared with polymyxin B exposure alone, concomitant gelofusine significantly increased cell viability as well as reduced LDH release, polymyxin B uptake, mitochondrial superoxide, and apoptosis. Gelofusine and methionine were more effective at reducing renal cell injury in combination than either agent alone. In conclusion, the mechanisms of renal protection by gelofusine involve decreasing cellular drug uptake, reducing subsequent oxidative stress and apoptosis activation. These findings would be valuable for translational research into clinical strategies to attenuate drug-associated acute kidney injury.NEW & NOTEWORTHY Gelofusine is a gelatinous saline solution with the potential to attenuate polymyxin-associated nephrotoxicity. We demonstrated that the mechanisms of gelofusine renal protection involve reducing polymyxin B uptake by proximal tubule cells, limiting subsequent oxidative stress and apoptosis activation. In addition, gelofusine was more effective at reducing cellular injury than a known antioxidant control, methionine, and a megalin knockout cell line, indicating that gelofusine likely has additional pharmacological properties besides only megalin inhibition.


Assuntos
Antibacterianos , Apoptose , Polimixina B , Animais , Polimixina B/farmacologia , Camundongos , Apoptose/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Linhagem Celular , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo
4.
FASEB J ; 37(2): e22727, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36583689

RESUMO

Transcriptional determinants in the skeletal muscle that govern exercise capacity, while poorly defined, could provide molecular insights into how exercise improves fitness. Here, we have elucidated the role of nuclear receptors, estrogen-related receptor alpha and gamma (ERRα/γ) in regulating myofibrillar composition, contractility, and exercise capacity in skeletal muscle. We used muscle-specific single or double (DKO) ERRα/γ knockout mice to investigate the effect of ERRα/γ deletion on muscle and exercise parameters. Individual knockout of ERRα/γ did not have a significant impact on the skeletal muscle. On the other hand, DKO mice exhibit pale muscles compared to wild-type (WT) littermates. RNA-seq analysis revealed a predominant decrease in expression of genes linked to mitochondrial and oxidative metabolism in DKO versus WT muscles. DKO muscles exhibit marked repression of oxidative enzymatic capacity, as well as mitochondrial number and size compared to WT muscles. Mitochondrial function is also impaired in single myofibers isolated from DKO versus WT muscles. In addition, mutant muscles exhibit reduced angiogenic gene expression and decreased capillarity. Consequently, DKO mice have a significantly reduced exercise capacity, further reflected in poor fatigue resistance of DKO mice in in vivo contraction assays. These results show that ERRα and ERRγ together are a critical link between muscle aerobic capacity and exercise tolerance. The ERRα/γ mutant mice could be valuable for understanding the long-term impact of impaired mitochondria and vascular supply on the pathogenesis of muscle-linked disorders.


Assuntos
Mitocôndrias , Músculo Esquelético , Camundongos , Animais , Músculo Esquelético/metabolismo , Camundongos Knockout , Mitocôndrias/metabolismo , Oxirredução , Estrogênios/metabolismo
5.
Arch Microbiol ; 206(5): 214, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616229

RESUMO

A complex interaction among virulence factors, host-genes and host immune system is considered to be responsible for dengue virus (DENV) infection and disease progression. Generation of auto-antibodies during DENV infection is a major phenomenon that plays a role in the pathophysiology of dengue hemorrhagic fever and dengue shock syndrome. Hemostasis, thrombocytopenia, hepatic endothelial dysfunction, and autoimmune blistering skin disease (pemphigus) are different clinical manifestations of dengue pathogenesis; produced due to the molecular mimicry of DENV proteins with self-antigens like coagulation factors, platelets and endothelial cell proteins. This review elaborately describes the current advancements in auto-antibody-mediated immunopathogenesis which inhibits coagulation cascade and promotes hyperfibrinolysis. Auto-antibodies like anti-endothelial cell antibodies-mediated hepatic inflammation during severe DENV infection have also been discussed. Overall, this comprehensive review provides insight to target auto-antibodies that may act as potential biomarkers for disease severity, and a ground for the development of therapeutic strategy against DENV.


Assuntos
Dengue , Humanos
6.
BMC Endocr Disord ; 24(1): 167, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215272

RESUMO

BACKGROUND: Multiple clinician adjustable parameters impact upon glycemia in people with type 1 diabetes (T1D) using Medtronic Mini Med 780G (MM780G) AHCL. These include glucose targets, carbohydrate ratios (CR), and active insulin time (AIT). Algorithm-based decision support advising upon potential settings adjustments may enhance clinical decision-making. METHODS: Single-arm, two-phase exploratory study developing decision support to commence and sustain AHCL. Participants commenced investigational MM780G, then 8 weeks Phase 1-initial optimization tool evaluation, involving algorithm-based decision support with weekly AIT and CR recommendations. Clinicians approved or rejected CR and AIT recommendations based on perceived safety per protocol. Co-design resulted in a refined algorithm evaluated in a further identically configured Phase 2. Phase 2 participants also transitioned to commercial MM780G following "Quick Start" (algorithm-derived tool determining initial AHCL settings using daily insulin dose and weight). We assessed efficacy, safety, and acceptability of decision support using glycemic metrics, and the proportion of accepted CR and AIT settings per phase. RESULTS: Fifty three participants commenced Phase 1 (mean age 24.4; Hba1c 61.5mmol/7.7%). The proportion of CR and AIT accepted by clinicians increased between Phases 1 and 2 respectively: CR 89.2% vs. 98.6%, p < 0.01; AIT 95.2% vs. 99.3%, p < 0.01. Between Phases, mean glucose percentage time < 3.9mmol (< 70mg/dl) reduced (2.1% vs. 1.4%, p = 0.04); change in mean TIR 3.9-10mmol/L (70-180mg/dl) was not statistically significant: 72.9% ± 7.8 and 73.5% ± 8.6. Quick start resulted in stable TIR, and glycemic metrics compared to international guidelines. CONCLUSION: The co-designed decision support tools were able to deliver safe and effective therapy. They can potentially reduce the burden of diabetes management related decision making for both health care practitioners and patients. TRIAL REGISTRATION: Prospectively registered with Australia/New Zealand Clinical Trials Registry(ANZCTR) on 30th March 2021 as study ACTRN12621000360819.


Assuntos
Glicemia , Diabetes Mellitus Tipo 1 , Hipoglicemiantes , Sistemas de Infusão de Insulina , Insulina , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/sangue , Masculino , Feminino , Insulina/administração & dosagem , Insulina/uso terapêutico , Adulto , Glicemia/análise , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Adulto Jovem , Técnicas de Apoio para a Decisão , Algoritmos , Adolescente , Sistemas de Apoio a Decisões Clínicas , Hemoglobinas Glicadas/análise , Seguimentos
7.
Biochem J ; 480(9): 629-647, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37075063

RESUMO

TRIM24 is a multi-functional chromatin reader, and it binds to the estrogen receptor to activate estrogen-dependent target genes associated with tumor development. TRIM24 is known to ubiquitinate p53 via an N-terminal RING domain and binds a specific combinatorial histone signature of H3K4me0/H3K23ac via its C-terminal plant homeodomain (PHD) and bromodomain (Bromo). Aberrant expression of TRIM24 positively correlates with H3K23ac levels, and high levels of both TRIM24 and H3K23ac predict poor survival of breast cancer patients. Little has been explored about the acetylated histone H4 (H4ac) signatures of TRIM24 and their biological functions. Herein, we report novel H4ac binding partners of TRIM24 and their localization in the genome. Isothermal titration calorimetry binding assay on the histone peptides revealed that the TRIM24 PHD-Bromo preferably binds to H4K5ac, H4K8ac, and H4K5acK8ac compared with other acetylated histone H4 ligands. Co-immunoprecipitation on the endogenous histones suggests that the recognition of H4ac by Bromo does not interfere with the recognition of H3K4me0 mark by the PHD domain of TRIM24. Consistent with this, TRIM24 PHD-Bromo exhibits minimal discrimination among H4ac binding partners at endogenous histone and nucleosome levels. Moreover, ChIP-seq analysis revealed that the H4K5ac and H4K8ac histone signatures strongly co-localize near the transcription start sites of different hub genes or TRIM24-targeted genes in breast cancer. In addition, the KEGG pathway analysis demonstrates that the TRIM24 and its H4ac targets are associated with several important biological pathways. Our findings describe that the H4ac recognition by TRIM24 PHD-Bromo enables access to the chromatin for specific transcriptional regulation.


Assuntos
Neoplasias da Mama , Histonas , Humanos , Feminino , Histonas/metabolismo , Cromatina , Proteínas de Ligação a DNA/metabolismo , Domínios Proteicos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Acetilação , Ligação Proteica , Proteínas de Transporte/metabolismo
8.
Ecotoxicol Environ Saf ; 270: 115832, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38141336

RESUMO

Agricultural productivity is constantly being forced to maintain yield stability to feed the enormously growing world population. However, shrinking arable and nutrient-deprived soil and abiotic and biotic stressor (s) in different magnitudes put additional challenges to achieving global food security. Though well-defined, the concept of macro, micronutrients, and beneficial elements is from a plant nutritional perspective. Among various micronutrients, selenium (Se) is essential in small amounts for the life cycle of organisms, including crops. Selenium has the potential to improve soil health, leading to the improvement of productivity and crop quality. However, Se possesses an immense encouraging phenomenon when supplied within the threshold limit, also having wide variations. The supplementation of Se has exhibited promising outcomes in lessening biotic and abiotic stress in various crops. Besides, bulk form, nano-Se, and biogenic-Se also revealed some merits and limitations. Literature suggests that the possibilities of biogenic-Se in stress alleviation and fortifying foods are encouraging. In this article, apart from adopting a combination of a conventional extensive review of the literature and bibliometric analysis, the authors have assessed the journey of Se in the "soil to spoon" perspective in a diverse agroecosystem to highlight the research gap area. There is no doubt that the time has come to seriously consider the tag of beneficial elements associated with Se, especially in the drastic global climate change era.


Assuntos
Selênio , Oligoelementos , Micronutrientes/análise , Solo , Agricultura , Produtos Agrícolas
9.
Biochemistry ; 62(2): 270-280, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35786907

RESUMO

Combinatorial readout of histone post-translational modifications by tandem reader modules mediates crosstalk among different histone modifications. To identify the domain-specific interactome of the tandem reader, we engineered the dual bromodomain of TATA-binding protein-associated factor-1 (TAF1) to carry a photoactivatable unnatural amino acid, 4-azido-l-phenylalanine (AzF), via amber suppressor mutagenesis. Using computational approaches, we modeled the targeted residues of TAF1 with AzF to predict the cross-linking distance between the reactive arylazide and its interacting partner. We developed three photoactivatable TAF1 tandem-bromodomain analogues, viz., Y1403AzF in bromodomain 1 (BD1), W1526AzF in bromodomain 2 (BD2), and Y1403AzF/W1526AzF in both BD1 and BD2. Circular dichroism and a thermal shift assay were used to confirm the structural integrity of the engineered readers. Using the TAF1 tandem-bromodomain analogues, we characterized their histone ligand binding properties by isothermal titration calorimetry and photo-cross-linking experiments. We found that the dual bromodomain of TAF1 independently binds and cross-links to different acetylated histone ligands. We further used the engineered BD1 and BD2 analogues of the TAF1 tandem readers to identify their domain-specific interacting partners at the cellular level. Both BD1 and BD2 independently cross-link to a unique interactome, and importantly, the dual cross-linker carrying TAF1 analogue could capture both BD1- and BD2-specific interactomes. Our work concludes that BD1 and BD2 of the TAF1 tandem reader independently recognize their interacting partners to regulate downstream cellular functions.


Assuntos
Azidas , Histonas , Histonas/metabolismo , Fotoquímica , Fatores de Transcrição/química , Ligação Proteica
10.
FASEB J ; 36(12): e22666, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36412933

RESUMO

Skeletal muscle atrophy is a prevalent complication in multiple chronic diseases and disuse conditions. Fibroblast growth factor-inducible 14 (Fn14) is a member of the TNF receptor superfamily and a bona fide receptor of the TWEAK cytokine. Accumulating evidence suggests that Fn14 levels are increased in catabolic conditions as well as during exercise. However, the role of Fn14 in the regulation of skeletal muscle mass and function remains poorly understood. In this study, through the generation of novel skeletal muscle-specific Fn14-knockout mice, we have investigated the muscle role of Fn14 in the regulation of exercise capacity and denervation-induced muscle atrophy. Our results demonstrate that there was no difference in skeletal muscle mass between control and muscle-specific Fn14-knockout mice. Nevertheless, the deletion of Fn14 in skeletal muscle significantly improved exercise capacity and resistance to fatigue. This effect of Fn14 deletion is associated with an increased proportion of oxidative myofibers and higher capillaries number per myofiber in skeletal muscle. Furthermore, our results demonstrate that targeted deletion of Fn14 inhibits denervation-induced muscle atrophy in adult mice. Deletion of Fn14 reduced the expression of components of the ubiquitin-proteasome system and non-canonical NF-kappa B signaling in denervated skeletal muscle, as well as increased the phosphorylation of Akt kinase and FoxO3a transcription factor. Collectively, our results demonstrate that targeted inhibition of Fn14 improves exercise tolerance and inhibits denervation-induced muscle atrophy in adult mice.


Assuntos
Tolerância ao Exercício , Fatores de Necrose Tumoral , Camundongos , Animais , Receptor de TWEAK/genética , Fatores de Necrose Tumoral/metabolismo , Atrofia Muscular/metabolismo , Camundongos Knockout
11.
Plant Cell Rep ; 42(10): 1571-1587, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37482559

RESUMO

KEY MESSAGE: We report the size dependent uptake of dsRNA loaded MSNPs into the leaves and roots of Nicotiana benthamiana plants and accessed for their relative reduction in Tomato leaf curl New Delhi viral load. A non-GMO method of RNA interference (RNAi) has been recently in practice through direct delivery of double stranded RNA into the plant cells. Tomato leaf curl New Delhi virus (ToLCNDV), a bipartitie begomovirus, is a significant viral pathogen of many crops in the Indian subcontinent. Conventional RNAi cargo delivery strategies for instance uses viral vectors and Agrobacterium-facilitated delivery, exhibiting specific host responses from the plant system. In the present study, we synthesized three different sizes of amine-functionalized mesoporous silica nanoparticles (amino-MSNPs) to mediate the delivery of dsRNA derived from the AC2 (dsAC2) gene of ToLCNDV and showed that these dsRNA loaded nanoparticles enabled effective reduction in viral load. Furthermore, we demonstrate that amino-MSNPs protected the dsRNA molecules from nuclease degradation, while the complex was efficiently taken up by the leaves and roots of Nicotiana benthamiana. The real time gene expression evaluation showed that plants treated with nanoparticles of different sizes ~ 10 nm (MSNPDEA), ~ 32 nm (MSNPTEA) and ~ 66 nm (MSNPNH3) showed five-, eleven- and threefold reduction of ToLCNDV in N. benthamiana, respectively compared to the plants treated with naked dsRNA. This work clearly demonstrates the size dependent internalization of amino-MSNPs and relative efficacy in transporting dsRNA into the plant system, which will be useful in convenient topical treatment to protect plants against their pathogens including viruses. Mesoporous silica nanoparticles loaded with FITC, checked for its uptake into Nicotiana benthamiana.


Assuntos
Begomovirus , Nanopartículas , Doenças das Plantas , RNA de Cadeia Dupla , Begomovirus/genética , Doenças das Plantas/prevenção & controle , Interferência de RNA , RNA de Cadeia Dupla/genética , Nicotiana/genética , Sistemas de Liberação de Medicamentos , Dióxido de Silício
12.
Biochemistry ; 61(17): 1774-1789, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35976792

RESUMO

HBO1 [HAT bound to the origin recognition complex (ORC)], a member of the MYST family of histone acetyltransferases (HATs), was initially identified as a binding partner of ORC that acetylates free histone H3, H4, and nucleosomal H3. It functions as a quaternary complex with the BRPF (BRPF1/2/3) scaffolding protein and two accessory proteins, ING4/5 and Eaf6. Interaction of BRPF2 with HBO1 has been shown to be important for regulating H3K14 acetylation during embryonic development. However, how BRPF2 directs the HBO1 HAT complex to chromatin to regulate its HAT activity toward nucleosomal substrates remains unclear. Our findings reveal novel interacting partners of the BRPF2 bromodomain that recognizes different acetyllysine residues on the N-terminus of histone H4, H3, and H2A and preferentially binds to H4K5ac, H4K8ac, and H4K5acK12ac modifications. In addition, mutational analysis of the BRPF2 bromodomain coupled with isothermal titration calorimetry binding and pull-down assays on the histone substrates identified critical residues responsible for acetyllysine binding. Moreover, the BRPF2 bromodomain could enrich H4K5ac mark-bearing mononucleosomes compared to other acetylated H4 marks. Consistent with this, ChIP-seq analysis revealed that BRPF2 strongly co-localizes with HBO1 at histone H4K5ac and H4K8ac marks near the transcription start sites in the genome. Our study provides novel insights into how the histone binding function of the BRPF2 bromodomain directs the recruitment of the HBO1 HAT complex to chromatin to regulate gene expression.


Assuntos
Código das Histonas , Histonas , Acetilação , Cromatina , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Nucleossomos , Processamento de Proteína Pós-Traducional
13.
FASEB J ; 35(8): e21821, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34325487

RESUMO

Skeletal muscle atrophy is a debilitating complication of many chronic disease states and disuse conditions including denervation. However, molecular and signaling mechanisms of muscle wasting remain less understood. Here, we demonstrate that the levels of several toll-like receptors (TLRs) and their downstream signaling adaptor, myeloid differentiation primary response 88 (MyD88), are induced in skeletal muscle of mice in response to sciatic nerve denervation. Muscle-specific ablation of MyD88 mitigates denervation-induced skeletal muscle atrophy in mice. Targeted ablation of MyD88 suppresses the components of ubiquitin-proteasome system, autophagy, and FOXO transcription factors in skeletal muscle during denervation. We also found that specific inhibition of MyD88 reduces the activation of canonical nuclear factor-kappa (NF-κB) pathway and expression of receptors for inflammatory cytokines in denervated muscle. In contrast, inhibition of MyD88 stimulates the activation of non-canonical NF-κB signaling in denervated skeletal muscle. Ablation of MyD88 also inhibits the denervation-induced increase in phosphorylation of AMPK without having any effect on the phosphorylation of mTOR. Moreover, targeted ablation of MyD88 inhibits the activation of a few components of the unfolded protein response (UPR) pathways, especially X-box protein 1 (XBP1). Importantly, myofiber-specific ablation of XBP1 mitigates denervation-induced skeletal muscle atrophy in mice. Collectively, our experiments suggest that TLR-MyD88 signaling mediates skeletal muscle wasting during denervation potentially through the activation of canonical NF-κB signaling, AMPK and UPR pathways.


Assuntos
Músculo Esquelético/inervação , Atrofia Muscular/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Animais , Biomarcadores/sangue , Estresse do Retículo Endoplasmático/fisiologia , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Resposta a Proteínas não Dobradas
14.
Arch Virol ; 166(10): 2905-2909, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34383166

RESUMO

Golden trumpet (Allamanda cathartica) plants were observed to exhibit mottling and distortion symptoms on leaves. The genome of an associated begomovirus (Al-K1) was amplified by rolling-circle amplification, cloned, and sequenced. The viral genome consisted of two circular ssDNA molecules, and the organization of the ORFs was similar to those of DNA-A and DNA-B components of bipartite begomoviruses. The size of DNA-A (KC202818) and DNA-B (MG969497) of the begomovirus was 2772 and 2690 nucleotides, respectively. Sequence analysis revealed that the DNA-A and DNA-B components shared the highest sequence identity with duranta leaf curl virus (MN537564, 87.8%) and cotton leaf curl Alabad virus (MH760452, 81.0%), respectively. Interestingly, the Al-K1 isolate shared significantly less nucleotide sequence identity with allamanda leaf curl virus (EF602306, 71.6%), the only monopartite begomovirus reported previously in golden trumpet from China. Al-K1 shared less than 91% sequence identity with other begomoviruses, and hence, according to the latest ICTV guidelines for species demarcation of begomoviruses, Al-K1 is proposed to be a member of a new species, and we propose the name "allamanda leaf mottle distortion virus" (AllLMoDV-[IN-Al_K1-12]) for this virus. AllLMoDV was detected in various golden trumpet samples from different locations by PCR with specific primers based on the genome sequence determined in this study. Our study provides evidence of the occurrence of a new bipartite begomovirus in a perennial ornamental plant in India.


Assuntos
Apocynaceae/virologia , Begomovirus/genética , Doenças das Plantas/virologia , Sequência de Bases , Begomovirus/classificação , DNA Viral/genética , Genoma Viral/genética , Índia , Fases de Leitura Aberta/genética , Filogenia , Folhas de Planta/virologia , Análise de Sequência de DNA , Especificidade da Espécie
15.
Ecotoxicol Environ Saf ; 212: 111960, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33513481

RESUMO

The development of low arsenic-accumulating varieties for the contaminated areas is one of the best options for reducing the dietary exposure of arsenic to human population through rice. In this study, grain-arsenic content in one hundred genotypes revealed a large variation ranging from 0.05 mg/kg to 0.49 mg/kg. Compared to high accumulating variety, Shatabdi, 6-8 times the transcript upregulation of Arsenic sequestering ATP binding cassette C1 type gene (ABCC1), was observed in first internode of low accumulating variety Gobindabhog when 5 mg/kg of arsenite was present in soil. A comparison of the genomic sequence of OsABCC1 identified 8 SNPs between the two genotypes; 5 in introns and 3 silent mutations in exons. We identified a PCR based co-dominant marker targeting an SNP (T/G) between the two genotypes, which clearly distinguished 100 genotypes into low (mean 0.14 mg/kg) and high (mean 0.35 mg/kg) accumulating groups. All aromatic genotypes, either long or small grain, carry the Gobindabhog-type ABCC1 allele and are low accumulators of arsenic. Gobindabhog allele carrying 62 RILs and NILs showed almost 40-50% less As-accumulation in grains relative to 84 RILs and NILs carrying Shatabdi type ABCC1-allele. The marker will be useful in introgression of low accumulating allele of OsABCC1 into high yielding photoperiod insensitive varietal backgrounds more easily and accurately.


Assuntos
Arsênio/metabolismo , Oryza/genética , Poluentes do Solo/metabolismo , Arsênio/análise , Arsenitos , Grão Comestível/metabolismo , Genótipo , Humanos , Oryza/metabolismo , Reação em Cadeia da Polimerase , Solo/química , Poluentes do Solo/análise
16.
An Acad Bras Cienc ; 93(1): e20190094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624711

RESUMO

Faunipollenites Bharadwaj is considered a junior synonym of Protohaploxypinus Samoilovich emend. Morbey. However, Indian workers claim it is a valid genus due to a poorly defined corpus and absence of folds in distal attachment. In India, a standard method is applied including the oxidization with HNO3 more than 48 hours (+10' of KOH). We analyze the effects of that treatment on the morphology of pollen grains of both genera in samples from the Permian of India and Brazil. The same samples are also processed with HCl, HF, two hours of HNO3 and 2' of KOH and slides are mounted after each step. Our analysis reveals that distinct or indistinct central body and presence/absence of folds in distal attachment do not change in contrast to the indistinct central body and mostly absence of folds from samples that underwent a longer period of oxidization (24-48 hours and KOH 10'). The synonymization of Faunipollenites to Protohaploxypinus is confirmed. Species of Faunipollenites are reassigned to the revised species of Protohaploxypinus. The usage of the latter genus and its species in Permian biostratigraphic studies of India will improve Gondwanan correlations and paleobiogeographic reconstructions in future studies.


Assuntos
Pólen , Aprepitanto , Brasil , Humanos , Índia
18.
Indian J Clin Biochem ; 34(4): 379-394, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686725

RESUMO

ABSTRACT: Tea polyphenols are known to prevent various ailments like cancer, atherosclerosis, hypertension and diabetes. Our study aimed at to decipher the gastroprotective effect of aqueous black tea extract (BTE) against ethanol-induced gastric damage and the role of BTE in modulating MMP-9 activity and expression, both in vivo and in vitro. The protective role of BTE was assessed in Sprague-Dawley rats after inducing damage with 70% ethanol. Human gastric adenocarcinoma cells (AGS) were treated with ethanol in ex vivo experiment. MMP-9 activity and expression were investigated through gelatin zymography and western blotting. Reactive oxygen species (ROS) generation was also studied by fluorescence spectroscopy and confocal microscopy, with or without treatment of BTE both in vivo and in vitro experiments. In addition, the effect of citric acid treated BTE (cBTE), which mimics lemon tea, was examined on ethanol-induced gastropathy. BTE exhibited antiulcer activity through reduction of glutathione depletion, lipid peroxidation, protein oxidation, ROS production and inflammatory cell infiltration in rat gastric tissues. In addition, BTE significantly inhibited synthesis and secretion of proMMP-9 both in vivo and in vitro. The mitochondrial enzymes succinate dehydrogenase and NADH oxidase in rat gastric tissues were downregulated by BTE while protecting gastric ulcer. Citric acid addition to BTE was observer to enrich the lead compound, catechin. Interestingly, cBTE showed higher anti-ulcer activity than the untreated one. BTE shows protective role against ethanol-induced gastric ulcer in rats through scavenging ROS and downregulating proMMP-9 activity. While cBTE shows better protection due to enrichment of catechin and removal of tannins in tea extract leading to enhanced inhibitory role on proMMP-9 activity and ROS production.

19.
Faraday Discuss ; 212(0): 359-381, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30311611

RESUMO

Understanding how the electronic structure of an aqueous solute is intricately bound up with the arrangement of a host liquid provides insight into how non-adiabatic photochemistry takes place in the condensed phase. For example, the presence of water provides additional solute-solvent interactions compared to non-polar solvents: changing the stability of ionized products and modifying the energies of low-lying excited valence states, as well as moving the point of intersection between potential surfaces. Thus, the locations and topography of conical intersections between these surfaces also change. The overall impact of the aqueous environment can be to modify the intricate photochemical and non-radiative pathways taking place after photoexcitation. Time-resolved photoelectron spectroscopy (TRPES) in a liquid micro-jet is implemented here to investigate the influence of water on the electronic structure and dynamics of indole, the chromophore of the amino acid tryptophan. TRPES is used to establish ultrafast relaxation pathways that vary as a function of excitation wavelength. In our experiment, aqueous indole was excited with femtosecond pulses centered at 292 nm and 266 nm. The vertical excitation energy of aqueous indole is extracted and found to be lowered by 0.5 eV in water relative to the gas phase. In the TRPES study, the spectral signature of 1La and evidence of solvated electron formation on an ultrafast timescale are observed. Our data also points to a possible contribution of the dissociative πσ* state, which can be accessed by a conical intersection (CI) with the 1La state.

20.
Mol Carcinog ; 56(9): 2086-2103, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28418078

RESUMO

Triple negative breast cancer (TNBC) tends to form aggressive tumors associated with high mortality and morbidity which urge the need for development of new therapeutic strategies. Recently, the normal metabolite Methylglyoxal (MG) has been documented for its anti-proliferative activity against human breast cancer. However, the mode of action of MG against TNBC remains open to question. In our study, we investigated the anticancer activity of MG in MDA MB 231 and 4T1 TNBC cell lines and elucidated the underlying mechanisms. MG dose-dependently caused cell death, induced apoptosis, and generated ROS in both the TNBC cell lines. Furthermore, such effects were attenuated in presence of ROS scavenger N-Acetyl cysteine. MG triggered mitochondrial cytochrome c release in the cytosol and up-regulated Bax while down-regulated anti-apoptotic protein Bcl-2. Additionally, MG treatment down-regulated phospho-akt and inhibited the nuclear translocation of the p65 subunit of NF-κB. MG exhibited a tumor suppressive effect in BALB/c mouse 4T1 breast tumor model as well. The cytotoxic effect was studied using MTT assay. Apoptosis, ROS generation, and mitochondrial dysfunction was evaluated by flow cytometry as well as fluorescence microscopy. Western blot assay was performed to analyze proteins responsible for apoptosis. This study demonstrated MG as a potent anticancer agent against TNBC both in vitro and in vivo. The findings will furnish fresh insights into the treatment of this subgroup of breast cancer.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Aldeído Pirúvico/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição RelA/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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