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1.
Exp Cell Res ; 435(2): 113934, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38237847

RESUMO

Myocardial infarction (MI) is one of the major cardiovascular diseases caused by diminished supply of nutrients and oxygen to the heart due to obstruction of the coronary artery. Different treatment options are available for cardiac diseases, however, they do not completely repair the damage. Therefore, reprogramming terminally differentiated fibroblasts using transcription factors is a promising strategy to differentiate them into cardiac like cells in vitro and to increase functional cardiomyocytes and reduce fibrotic scar in vivo. In this study, skin fibroblasts were selected for reprogramming because they serve as a convenient source for the autologous cell therapy. Fibroblasts were isolated from skin of rat pups, propagated, and directly reprogrammed towards cardiac lineage. For reprogramming, two different approaches were adopted, i.e., cells were transfected with: (1) combination of cardiac transcription factors; GATA4, MEF2c, Nkx2.5 (GMN), and (2) combination of cardiac transcription factors; GATA4, MEF2c, Nkx2.5, and iPSC factors; Oct4, Klf4, Sox2 and cMyc (GMNO). After 72 h of transfection, cells were analyzed for the expression of cardiac markers at the mRNA and protein levels. For in vivo study, rat MI models were developed by ligating the left anterior descending coronary artery and the reprogrammed cells were transplanted in the infarcted heart. qPCR results showed that the reprogrammed cells exhibited significant upregulation of cardiac genes. Immunocytochemistry analysis further confirmed cardiomyogenic differentiation of the reprogrammed cells. For the assessment of cardiac function, animals were analyzed via echocardiography after 2 and 4 weeks of cell transplantation. Echocardiographic results showed that the hearts transplanted with the reprogrammed cells improved ejection fraction, fractional shortening, left ventricular internal systolic and diastolic dimensions, and end systolic and diastolic volumes. After 4 weeks of cell transplantation, heart tissues were harvested and processed for histology. The histological analysis showed that the reprogrammed cells improved wall thickness of left ventricle and reduced fibrosis significantly as compared to the control. It is concluded from the study that novel combination of cardiac transcription factors directly reprogrammed skin fibroblasts and differentiated them into cardiomyocytes. These differentiated cells showed cardiomyogenic characters in vitro, and reduced fibrosis and improved cardiac function in vivo. Furthermore, direct reprogramming of fibroblasts transfected with cardiac transcription factors showed better regeneration of the injured myocardium and improved cardiac function as compared to the indirect approach in which combination of cardiac and iPSC factors were used. The study after further optimization could be used as a better strategy for cell-based therapeutic approaches for cardiovascular diseases.


Assuntos
Infarto do Miocárdio , Miócitos Cardíacos , Ratos , Animais , Miócitos Cardíacos/metabolismo , Diferenciação Celular , Infarto do Miocárdio/patologia , Fatores de Transcrição/metabolismo , Fibroblastos/metabolismo , Fibrose , Reprogramação Celular
2.
Semin Cancer Biol ; 92: 102-127, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37054904

RESUMO

Cerebral ischemic stroke and glioma are the two leading causes of patient mortality globally. Despite physiological variations, 1 in 10 people who have an ischemic stroke go on to develop brain cancer, most notably gliomas. In addition, glioma treatments have also been shown to increase the risk of ischemic strokes. Stroke occurs more frequently in cancer patients than in the general population, according to traditional literature. Unbelievably, these events share multiple pathways, but the precise mechanism underlying their co-occurrence remains unknown. Transcription factors (TFs), the main components of gene expression programmes, finally determine the fate of cells and homeostasis. Both ischemic stroke and glioma exhibit aberrant expression of a large number of TFs, which are strongly linked to the pathophysiology and progression of both diseases. The precise genomic binding locations of TFs and how TF binding ultimately relates to transcriptional regulation remain elusive despite a strong interest in understanding how TFs regulate gene expression in both stroke and glioma. As a result, the importance of continuing efforts to understand TF-mediated gene regulation is highlighted in this review, along with some of the primary shared events in stroke and glioma.


Assuntos
Neoplasias Encefálicas , Glioma , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Glioma/complicações , Glioma/genética , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/genética , Acidente Vascular Cerebral/genética
3.
Circulation ; 147(4): 324-337, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36314132

RESUMO

BACKGROUND: Developmental cardiac tissue holds remarkable capacity to regenerate after injury and consists of regenerative mononuclear diploid cardiomyocytes. On maturation, mononuclear diploid cardiomyocytes become binucleated or polyploid and exit the cell cycle. Cardiomyocyte metabolism undergoes a profound shift that coincides with cessation of regeneration in the postnatal heart. However, whether reprogramming metabolism promotes persistence of regenerative mononuclear diploid cardiomyocytes enhancing cardiac function and repair after injury is unknown. Here, we identify a novel role for RNA-binding protein LIN28a, a master regulator of cellular metabolism in cardiac repair after injury. METHODS: LIN28a overexpression was tested using mouse transgenesis on postnatal cardiomyocyte numbers, cell cycle, and response to apical resection injury. With the use of neonatal and adult cell culture systems and adult and Mosaic Analysis with Double Markers myocardial injury models in mice, the effect of LIN28a overexpression on cardiomyocyte cell cycle and metabolism was tested. Last, isolated adult cardiomyocytes from LIN28a and wild-type mice 4 days after myocardial injury were used for RNA-immunoprecipitation sequencing. RESULTS: LIN28a was found to be active primarily during cardiac development and rapidly decreases after birth. LIN28a reintroduction at postnatal day (P) 1, P3, P5, and P7 decreased maturation-associated polyploidization, nucleation, and cell size, enhancing cardiomyocyte cell cycle activity in LIN28a transgenic pups compared with wild-type littermates. Moreover, LIN28a overexpression extended cardiomyocyte cell cycle activity beyond P7 concurrent with increased cardiac function 30 days after apical resection. In the adult heart, LIN28a overexpression attenuated cardiomyocyte apoptosis, enhanced cell cycle activity, cardiac function, and survival in mice 12 weeks after myocardial infarction compared with wild-type littermate controls. Instead, LIN28a small molecule inhibitor attenuated the proreparative effects of LIN28a on the heart. Neonatal rat ventricular myocytes overexpressing LIN28a mechanistically showed increased glycolysis, ATP production, and levels of metabolic enzymes compared with control. LIN28a immunoprecipitation followed by RNA-immunoprecipitation sequencing in cardiomyocytes isolated from LIN28a-overexpressing hearts after injury identified long noncoding RNA-H19 as its most significantly altered target. Ablation of long noncoding RNA-H19 blunted LIN28a-induced enhancement on cardiomyocyte metabolism and cell cycle activity. CONCLUSIONS: Collectively, LIN28a reprograms cardiomyocyte metabolism and promotes persistence of mononuclear diploid cardiomyocytes in the injured heart, enhancing proreparative processes, thereby linking cardiomyocyte metabolism to regulation of ploidy/nucleation and repair in the heart.


Assuntos
Infarto do Miocárdio , RNA Longo não Codificante , Proteínas de Ligação a RNA , Animais , Camundongos , Ratos , Animais Recém-Nascidos , Ciclo Celular , Proliferação de Células , Coração/fisiologia , Miócitos Cardíacos/metabolismo , Regeneração/fisiologia , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/metabolismo
4.
Stem Cells ; 41(11): 987-1005, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37591309

RESUMO

Stroke is a major contributor to mortality and impairment on a global scale, with few effective treatments available. Aberrant expression of various non-coding RNAs (ncRNAs) has been identified after stroke onset, impacting neurogenesis, angiogenesis, apoptosis, and autophagy. The roles and mechanisms of ncRNAs hold great promise for future ischemic stroke treatments, as they could modify stroke impact and course on a well-controllable molecular level. Exploring the functions and underlying mechanisms of ncRNAs after stroke has the potential to unveil novel therapeutic targets for the treatment of stroke and may also pave the way toward novel and more precise diagnostic options for stroke and stroke outcomes. This review emphasizes the importance of ncRNAs in the treatment of stroke and their potential as therapeutic targets.


Assuntos
AVC Isquêmico , RNA Longo não Codificante , Acidente Vascular Cerebral , Humanos , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/terapia , Neurogênese/genética
5.
Brain Behav Immun ; 116: 70-84, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38040385

RESUMO

Alzheimer's disease (AD) is the seventh most common cause of mortality and one of the major causes of disability and vulnerability in the elderly. AD is characterized by gradual cognitive deterioration, the buildup of misfolded amyloid beta (Aß) peptide, and the generation of neurofibrillary tangles. Despite enormous scientific progress, there is no effective cure for AD. Thus, exploring new treatment options to stop AD or at least slow down its progress is important. In this study, we investigated the potential therapeutic effects of MCC950 on NLRP3-mediated inflammasome-driven inflammation and autophagy in AD. Rats treated with streptozotocin (STZ) exhibited simultaneous activation of the NLRP3 inflammasome and autophagy, as confirmed by Western blot, immunofluorescence, and co-immunoprecipitation analyses. MCC950, a specific NLRP3 inhibitor, was intraperitoneally administered (50 mg/kg body weight) to rats with AD-like symptoms induced by intracerebroventricular STZ injections (3 mg/kg body weight). MCC950 effectively suppressed STZ-induced cognitive impairment and anxiety by inhibiting NLRP3-dependent neuroinflammation. Moreover, our findings indicate that MCC950 exerts neuroprotective effects by attenuating autophagy in neuronal cells. The inhibiting effects of MCC950 on inflammasome activation and autophagy were reproduced in vitro, provding further mechansistic insights into MCC950 therapeutic action. Our findings suggest that MCC950 impedes the progression of AD and may also improve cognitive function through the mitigation of autophagy and NLRP3 inflammasome inhibition.


Assuntos
Doença de Alzheimer , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Ratos , Animais , Idoso , Doença de Alzheimer/tratamento farmacológico , Inflamassomos , Peptídeos beta-Amiloides/farmacologia , Doenças Neuroinflamatórias , Sulfonamidas/farmacologia , Cognição , Autofagia , Peso Corporal
6.
Arch Microbiol ; 206(4): 196, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546887

RESUMO

The world is concerned about the emergence of pathogens and the occurrence and spread of antibiotic resistance among pathogens. Drug development requires time to combat these issues. Consequently, drug development from natural sources is unavoidable. Cryosphere represents a gigantic source of microbes that could be the bioprospecting source of natural products with unique scaffolds as molecules or drug templates. This review focuses on the novel source of drug discovery and cryospheric environments as a potential source for microbial metabolites having potential medicinal applications. Furthermore, the problems encountered in discovering metabolites from cold-adapted microbes and their resolutions are discussed. By adopting modern practical approaches, the discovery of bioactive compounds might fulfill the demand for new drug development.


Assuntos
Produtos Biológicos , Descoberta de Drogas , Bioprospecção , Produtos Biológicos/farmacologia
7.
Biomed Chromatogr ; 38(9): e5936, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38956791

RESUMO

Mangifera indica peels are a rich source of diverse flavonoids and xanthonoids; however, generally these are discarded. Computational studies revealed that mangiferin significantly interacts with amino acid residues of transcriptional regulators 1IK3, 3TOP, and 4f5S. The methanolic extract of Langra variety of mangoes contained the least phenol concentrations (22.6 ± 0.32 mg/gGAE [gallic acid equivalent]) compared to the chloroform (214.8 ± 0.12 mg/gGAE) and ethyl acetate fractions (195.6 ± 0.14 mg/gGAE). Similarly, the methanolic extract of Sindhri variety contained lower phenol concentrations (42.3 ± 0.13 mg/gRUE [relative utilization efficiency]) compared with the chloroform (85.6 ± 0.15 mg/gGAE) and ethyl acetate (76.1 ± 0.32 mg/gGAE) fractions. Langra extract exhibited significant α-glucosidase inhibition (IC50 0.06 mg/mL), whereas the ethyl acetate fraction was highly active (IC50 0.12 mg/mL) in Sindhri variety. Mangiferin exhibited significant inhibition (IC50 0.026 mg/mL). A moderate inhibition of 15-LOX was observed in all samples, whereas mangiferin was least active. In advanced glycation end product inhibition assay, the chloroform fraction of Langra variety exhibited significant inhibition in nonoxidative (IC50 64.4 µg/mL) and oxidative modes (IC50 54.7 µg/mL). It was concluded that both Langra and Sindhri peel extracts and fractions possess significant antidiabetic activities. The results suggest the potential use of peel waste in the management and complications of diabetes.


Assuntos
Antioxidantes , Produtos Finais de Glicação Avançada , Hipoglicemiantes , Mangifera , Extratos Vegetais , Xantonas , Xantonas/química , Xantonas/farmacologia , Xantonas/análise , Mangifera/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/análise , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/análise , Produtos Finais de Glicação Avançada/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Simulação de Acoplamento Molecular , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/análise , Simulação por Computador
8.
Heart Fail Clin ; 20(4): 407-417, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39216926

RESUMO

Life-threatening dysrhythmias remain a significant cause of mortality in patients with nonischemic cardiomyopathy (NICM). Implantable cardioverter-defibrillators (ICD) effectively reduce mortality in patients who have survived a life-threatening arrhythmic event. The evidence for survival benefit of primary prevention ICD for patients with high-risk NICM on guideline-directed medical therapy is not as robust, with efficacy questioned by recent studies. In this review, we summarize the data on the risk of life-threatening arrhythmias in NICM, the recommendations, and the evidence supporting the efficacy of primary prevention ICD, and highlight tools that may improve the identification of patients who could benefit from primary prevention ICD implantation.


Assuntos
Cardiomiopatias , Tomada de Decisão Clínica , Morte Súbita Cardíaca , Desfibriladores Implantáveis , Humanos , Cardiomiopatias/terapia , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Prevenção Primária/métodos , Arritmias Cardíacas/terapia
9.
J Pak Med Assoc ; 74(6): 1172-1174, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38948993

RESUMO

The most common twin ectopic pregnancy is heterotopic (1/7000). We are reporting a rare case of twin tubo-ovarian ectopic pregnancy, which was presented in the emergency department of Ayub Teaching Hospital Abbottabad. A 30- year-old female arrived with worsening lower abdominal pain persisting for three weeks. She also had per-vaginal bleeding with passage of clots 1week ago. Clinical examination revealed a tense abdomen with tenderness in the left iliac fossa. Per-vaginally, there was cervical motion tenderness and fullness in the posterior fornix. Beta HCG level revealed a sub-optimal rise whereas Transabdominal ultrasound showed an echogenic shadow in the left ovary. The uterus appeared normal. On exploratory laparotomy a large left ovarian mass was seen with ruptured chronic right tubal pregnancy with adhesions. On cut-section of the ovary, a small foetus was evident. We have concluded that in case of subacute abdominal pain and an-echogenic mass on ultrasonography in reproductive age contralateral adnexa should be accessed to exclude contralateral ectopic pregnancy.


Assuntos
Gravidez Ovariana , Gravidez Tubária , Gravidez de Gêmeos , Humanos , Feminino , Gravidez , Adulto , Gravidez Tubária/cirurgia , Gravidez Tubária/diagnóstico , Gravidez Tubária/diagnóstico por imagem , Gravidez Ovariana/diagnóstico , Gravidez Ovariana/cirurgia , Dor Abdominal/etiologia , Ultrassonografia/métodos
10.
Stem Cells ; 40(5): 468-478, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35294968

RESUMO

Stem cell therapies have emerged as a promising treatment strategy for various diseases characterized by ischemic injury such as ischemic stroke. Cell survival after transplantation remains a critical issue. We investigated the impact of oxidative stress, being typically present in ischemically challenged tissue, on human dental pulp stem cells (hDPSC) and human mesenchymal stem cells (hMSC). We used oxygen-glucose deprivation (OGD) to induce oxidative stress in hDPSC and hMSC. OGD-induced generation of O2•- or H2O2 enhanced autophagy by inducing the expression of activating molecule in BECN1-regulated autophagy protein 1 (Ambra1) and Beclin1 in both cell types. However, hDPSC and hMSC pre-conditioning using reactive oxygen species (ROS) scavengers significantly repressed the expression of Ambra1 and Beclin1 and inactivated autophagy. O2•- or H2O2 acted upstream of autophagy, and the mechanism was unidirectional. Furthermore, our findings revealed ROS-p38-Erk1/2 involvement. Pre-treatment with selective inhibitors of p38 and Erk1/2 pathways (SB202190 and PD98059) reversed OGD effects on the expression of Ambra1 and Beclin1, suggesting that these pathways induced oxidative stress-mediated autophagy. SIRT3 depletion was found to be associated with increased oxidative stress and activation of p38 and Erk1/2 MAPKs pathways. Global ROS inhibition by NAC or a combination of polyethylene glycol-superoxide dismutase (PEG-SOD) and polyethylene glycol-catalase (PEG-catalase) further confirmed that O2•- or H2O2 or a combination of both impacts stems cell viability by inducing autophagy. Furthermore, autophagy inhibition by 3-methyladenine (3-MA) significantly improved hDPSC viability. These findings contribute to a better understanding of post-transplantation hDPSC and hMSC death and may deduce strategies to minimize therapeutic cell loss under oxidative stress.


Assuntos
Autofagia , Peróxido de Hidrogênio , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Proteína Beclina-1/metabolismo , Proteína Beclina-1/farmacologia , Sobrevivência Celular , Glucose/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Oxigênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/metabolismo
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