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Abstract Renal involvement is one of the most severe morbidities of Fabry disease (FD), a multisystemic lysosomal storage disease with an X-linked inheritance pattern. It results from pathogenic variants in the GLA gene (Xq22.2), which encodes the production of alpha-galactosidase A (α-Gal), responsible for glycosphingolipid metabolism. Insufficient activity of this lysosomal enzyme generates deposits of unprocessed intermediate substrates, especially globotriaosylceramide (Gb3) and derivatives, triggering cellular injury and subsequently, multiple organ dysfunction, including chronic nephropathy. Kidney injury in FD is classically attributed to Gb3 deposits in renal cells, with podocytes being the main target of the pathological process, in which structural and functional alterations are established early and severely. This configures a typical hereditary metabolic podocytopathy, whose clinical manifestations are proteinuria and progressive renal failure. Although late clinical outcomes and morphological changes are well established in this nephropathy, the molecular mechanisms that trigger and accelerate podocyte injury have not yet been fully elucidated. Podocytes are highly specialized and differentiated cells that cover the outer surface of glomerular capillaries, playing a crucial role in preserving the structure and function of the glomerular filtration barrier. They are frequent targets of injury in many nephropathies. Furthermore, dysfunction and depletion of glomerular podocytes are essential events implicated in the pathogenesis of chronic kidney disease progression. We will review the biology of podocytes and their crucial role in regulating the glomerular filtration barrier, analyzing the main pathogenic pathways involved in podocyte injury, especially related to FD nephropathy.
Resumo O acometimento renal é uma das mais severas morbidades da doença de Fabry (DF), enfermidade multissistêmica de depósito lisossômico com padrão de herança ligada ao cromossomo X, decorrente de variantes patogênicas do gene GLA (Xq22.2), que codifica a produção de alfa-galactosidase A (α-Gal), responsável pelo metabolismo de glicoesfingolipídeos. A atividade insuficiente dessa enzima lisossômica gera depósitos de substratos intermediários não processados, especialmente do globotriaosilceramida (Gb3) e derivados, desencadeando injúria celular e, posteriormente, disfunção de múltiplos órgãos, incluindo a nefropatia crônica. A lesão renal na DF é classicamente atribuída aos depósitos de Gb3 nas células renais, sendo os podócitos o alvo principal do processo patológico, nos quais as alterações estruturais e funcionais são instaladas de forma precoce e severa, configurando uma podocitopatia metabólica hereditária típica, cujas manifestações clínicas são proteinúria e falência renal progressiva. Embora os desfechos clínicos tardios e as alterações morfológicas estejam bem estabelecidos nessa nefropatia, os mecanismos moleculares que deflagram e aceleram a injúria podocitária ainda não estão completamente elucidados. Podócitos são células altamente especializadas e diferenciadas que revestem a superfície externa dos capilares glomerulares, desempenhando papel essencial na preservação da estrutura e função da barreira de filtração glomerular, sendo alvos frequentes de injúria em muitas nefropatias. A disfunção e depleção dos podócitos glomerulares são, além disso, eventos cruciais implicados na patogênese da progressão da doença renal crônica. Revisaremos a biologia dos podócitos e seu papel na regulação da barreira de filtração glomerular, analisando as principais vias patogênicas envolvidas na lesão podocitária, especialmente relacionadas à nefropatia da DF.
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SUMMARY: Marein is a flavonoid compound that reduces blood glucose and lipids and has a protective effect in diabetes. However, the effect and mechanism(s) of marein on renal endothelial-mesenchymal transition in diabetic kidney disease (DKD) have not been elucidated. In this study, single-cell sequencing data on DKD were analyzed using a bioinformation method, and the data underwent reduced dimension clustering. It was found that endothelial cells could be divided into five subclusters. The developmental sequence of the subclusters was 0, 1, 4, 2, and 3, of which subcluster 3 had the most interstitial phenotype.The expression of mesenchymal marker protein:Vimentin(VIM), Fibronectin(FN1), and fibroblast growth factor receptor 1 (FGFR1) increased with the conversion of subclusters. In db/db mice aged 13-14 weeks, which develop DKD complications after 8-12 weeks of age, marein reduced blood levels of glucose, creatinine, and urea nitrogen, improved structural damage in kidney tissue, and reduced collagen deposition and the expression of FN1 and VIM. Marein also up-regulated autophagy marker:Light chain 3II/I(LC3II/I) and decreased FGFR1 expression in renal tissue. In an endothelial-mesenchymal transition model, a high glucose level induced a phenotypic change in human umbilical vein endothelial cells. Marein decreased endothelial cell migration, improved endothelial cell morphology, and decreased the expression of VIM and FN1. The use of the FGFR1 inhibitor, AZD4547, and autophagy inhibitor, 3-Methyladenine(3-MA), further demonstrated the inhibitory effect of marein on high glucose-induced endothelial-mesenchymal transition by reducing FGFR1 expression and up-regulating the autophagy marker protein, LC3II/I. In conclusion, this study suggests that marein has a protective effect on renal endothelial- mesenchymal transition in DKD, which may be mediated by inducing autophagy and down-regulating FGFR1 expression.
La mareína es un compuesto flavonoide que reduce la glucosa y los lípidos en sangre y tiene un efecto protector en la diabetes. Sin embargo, no se han dilucidado el efecto y los mecanismos de la mareína sobre la transición endotelial- mesenquimatosa renal en la enfermedad renal diabética (ERD). En este estudio, los datos de secuenciación unicelular sobre DKD se analizaron utilizando un método de bioinformación y los datos se sometieron a una agrupación de dimensiones reducidas. Se descubrió que las células endoteliales podían dividirse en cinco subgrupos. La secuencia de desarrollo de los subgrupos fue 0, 1, 4, 2 y 3, de los cuales el subgrupo 3 tenía el fenotipo más intersticial. La expresión de la proteína marcadora mesenquimatosa: vimentina (VIM), fibronectina (FN1) y receptor del factor de crecimiento de fibroblastos. 1 (FGFR1) aumentó con la conversión de subgrupos. En ratones db/db de 13 a 14 semanas de edad, que desarrollan complicaciones de DKD después de las 8 a 12 semanas de edad, la mareína redujo los niveles sanguíneos de glucosa, creatinina y nitrógeno ureico, mejoró el daño estructural en el tejido renal y redujo la deposición y expresión de colágeno de FN1 y VIM. Marein también aumentó el marcador de autofagia: Cadena ligera 3II/I (LC3II/I) y disminuyó la expresión de FGFR1 en el tejido renal. En un modelo de transición endotelial-mesenquimal, un nivel alto de glucosa indujo un cambio fenotípico en las células endoteliales de la vena umbilical humana. Marein disminuyó la migración de células endoteliales, mejoró la morfología de las células endoteliales y disminuyó la expresión de VIM y FN1. El uso del inhibidor de FGFR1, AZD4547, y del inhibidor de la autofagia, 3-metiladenina (3-MA), demostró aún más el efecto inhibidor de la mareína en la transición endotelial-mesenquimal inducida por niveles altos de glucosa al reducir la expresión de FGFR1 y regular positivamente la proteína marcadora de autofagia. , LC3II/I. En conclusión, este estudio sugiere que la mareína tiene un efecto protector sobre la transición endotelial-mesenquimatosa renal en la ERC, que puede estar mediada por la inducción de autofagia y la regulación negativa de la expresión de FGFR1.
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Chalconas/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Transição Endotélio-Mesênquima , Autofagia , Biologia Computacional , Receptor Tipo 1 de Fator de Crescimento de FibroblastosRESUMO
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
Insufficient evidence regarding how maternal undernutrition affects craniofacial bone development persists. With its unique focus on the impact of gestational protein restriction on calvaria and mandible osteogenesis, this study aims to fill, at least in part, this gap. Female mice were mated and randomized into NP (normal protein) or LP (low protein) groups. On the 18th gestational day (GD), male embryos were collected and submitted to microtomography (µCT), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), PCR, and autophagy dynamic analyses. The study shows that the LP offspring exhibited lower body mass than the NP group, with µCT analysis revealing no volumetric differences in fetus's head. EDS analysis showed lower calcium and higher phosphorus percentages in mandibles and calvaria. SEM assessment evidenced higher hydroxyapatite crystal-like (HC) deposition on the calvaria surface in LP fetus. Conversely, lower HC deposition was observed on the mandible surface, suggesting delayed matrix mineralization in LP fetuses with a higher percentage of collagen fibers in the mandible bone. The autophagy process was reduced in the mesenchyme of LP fetuses. PCR array analysis of 84 genes revealed 27 genes with differential expression in the LP progeny-moreover, increased mRNA levels of Akt1, Mtor, Nfkb, and Smad1 in the LP offspring. In conclusion, the results suggest that gestational protein restriction anticipated bone differentiation in utero, before 18GD, where this process is reduced compared to the control, leading to the reduction in bone area at 15 postnatal day previously observed. These findings provide insights into the molecular and cellular mechanisms of mandible development and suggest potential implications for the Developmental Origins of Health and Disease (DOHaD).
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Autophagy engulfs cellular components in double-membrane-bound autophagosomes for clearance and recycling after fusion with lysosomes. Thus, autophagy is a key process for maintaining proteostasis and a powerful cell-intrinsic host defense mechanism, protecting cells against pathogens by targeting them through a specific form of selective autophagy known as xenophagy. In this context, ubiquitination acts as a signal of recognition of the cargoes for autophagic receptors, which direct them towards autophagosomes for subsequent breakdown. Nevertheless, autophagy can carry out a dual role since numerous viruses including members of the Orthoherpesviridae family can either inhibit or exploit autophagy for its own benefit and to replicate within host cells. There is growing evidence that Herpes simplex virus type 1 (HSV-1), a highly prevalent human pathogen that infects epidermal keratinocytes and sensitive neurons, is capable of negatively modulating autophagy. Since the effects of HSV-1 infection on autophagic receptors have been poorly explored, this study aims to understand the consequences of HSV-1 productive infection on the levels of the major autophagic receptors involved in xenophagy, key proteins in the recruitment of intracellular pathogens into autophagosomes. We found that productive HSV-1 infection in human neuroglioma cells and keratinocytes causes a reduction in the total levels of Ub conjugates and decreases protein levels of autophagic receptors, including SQSTM1/p62, OPTN1, NBR1, and NDP52, a phenotype that is also accompanied by reduced levels of LC3-I and LC3-II, which interact directly with autophagic receptors. Mechanistically, we show these phenotypes are the result of xenophagy activation in the early stages of productive HSV-1 infection to limit virus replication, thereby reducing progeny HSV-1 yield. Additionally, we found that the removal of the tegument HSV-1 protein US11, a recognized viral factor that counteracts autophagy in host cells, enhances the clearance of autophagic receptors, with a significant reduction in the progeny HSV-1 yield. Moreover, the removal of US11 increases the ubiquitination of SQSTM1/p62, indicating that US11 slows down the autophagy turnover of autophagy receptors. Overall, our findings suggest that xenophagy is a potent host defense against HSV-1 replication and reveals the role of the autophagic receptors in the delivery of HSV-1 to clearance via xenophagy.
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Autofagia , Herpesvirus Humano 1 , Humanos , Herpesvirus Humano 1/fisiologia , Herpes Simples/virologia , Herpes Simples/imunologia , Herpes Simples/metabolismo , Macroautofagia , Replicação Viral , Autofagossomos/metabolismo , Queratinócitos/virologia , Queratinócitos/metabolismo , Proteína Sequestossoma-1/metabolismo , Interações Hospedeiro-Patógeno , Animais , Proteínas Nucleares , Proteínas de Ciclo Celular , Proteínas de Membrana TransportadorasRESUMO
It is well established that microRNA-21 (miR-21) targets phosphatase and tensin homolog (PTEN), facilitating epithelial-to-mesenchymal transition (EMT) and drug resistance in cancer. Recent evidence indicates that PTEN activates its pseudogene-derived long non-coding RNA, PTENP1, which in turn inhibits miR-21. However, the dynamics of PTEN, miR-21, and PTENP1 in the DNA damage response (DDR) remain unclear. Thus, we propose a dynamic Boolean network model by integrating the published literature from various cancers. Our model shows good agreement with the experimental findings from breast cancer, hepatocellular carcinoma (HCC), and oral squamous cell carcinoma (OSCC), elucidating how DDR activation transitions from the intra-S phase to the G2 checkpoint, leading to a cascade of cellular responses such as cell cycle arrest, senescence, autophagy, apoptosis, drug resistance, and EMT. Model validation underscores the roles of PTENP1, miR-21, and PTEN in modulating EMT and drug resistance. Furthermore, our analysis reveals nine novel feedback loops, eight positive and one negative, mediated by PTEN and implicated in DDR cell fate determination, including pathways related to drug resistance and EMT. Our work presents a comprehensive framework for investigating cellular responses following DDR, underscoring the therapeutic potential of targeting PTEN, miR-21, and PTENP1 in cancer treatment.
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Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , MicroRNAs , PTEN Fosfo-Hidrolase , RNA Longo não Codificante , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Transição Epitelial-Mesenquimal/genética , Resistencia a Medicamentos Antineoplásicos/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Apoptose/genética , Transdução de SinaisRESUMO
Glioblastoma is a malignant neoplasm that develops in the central nervous system and is characterized by high rates of cell proliferation and invasion, presenting resistance to treatments and a poor prognosis. Photodynamic therapy (PDT) is a therapeutic modality that can be applied in oncological cases and stands out for being less invasive. Photosensitizers (PS) of natural origin gained prominence in PDT. Curcumin (CUR) is a natural compound that has been used in PDT, considered a promising PS. In this work, we evaluated the effects of PDT-mediated CUR and near-infrared radiation (NIR) in glioblastoma cells. Through trypan blue exclusion analysis, we chose the concentration of 5 µM of CUR and the dose of 2 J/cm2 of NIR that showed better responses in reducing the viable cell number in the C6 cell line and did not show cytotoxic/cytostatic effects in the HaCat cell line. Our results show that there is a positive interaction between CUR and NIR as a PDT model since there was an increase in ROS levels, a decrease in cell proliferation, increase in cytotoxicity with cell death by autophagy and necrosis, in addition to the presence of oxidative damage to proteins. These results suggest that the use of CUR and NIR is a promising strategy for the antitumor application of PDT.
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Sobrevivência Celular , Curcumina , Glioblastoma , Raios Infravermelhos , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Curcumina/farmacologia , Glioblastoma/tratamento farmacológico , Humanos , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Animais , Antineoplásicos/farmacologia , RatosRESUMO
This review summarizes recent progress in our current understanding of the mechanisms underlying the cell death pathways in bryophytes, focusing on conserved pathways and particularities in comparison to angiosperms. Regulated cell death (RCD) plays key roles during essential processes along the plant life cycle. It is part of specific developmental programmes and maintains homeostasis of the organism in response to unfavourable environments. Bryophytes could provide valuable models to study developmental RCD processes as well as those triggered by biotic and abiotic stresses. Some pathways analogous to those present in angiosperms occur in the gametophytic haploid generation of bryophytes, allowing direct genetic studies. In this review, we focus on such RCD programmes, identifying core conserved mechanisms and raising new key questions to analyse RCD from an evolutionary perspective.
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Briófitas , Briófitas/genética , Briófitas/fisiologia , Briófitas/crescimento & desenvolvimento , Morte Celular/fisiologia , Regulação da Expressão Gênica de Plantas , Transdução de Sinais , Modelos Biológicos , Morte Celular Regulada/fisiologia , Morte Celular Regulada/genética , Magnoliopsida/genética , Magnoliopsida/fisiologia , Magnoliopsida/crescimento & desenvolvimentoRESUMO
BACKGROUND: Diabetic neuropathy (DN) is recognized as a significant complication arising from diabetes mellitus (DM). Pathogenesis of DN is accelerated by endoplasmic reticulum (ER) stress, which inhibits autophagy and contributes to disease progression. Autophagy is a highly conserved mechanism crucial in mitigating cell death induced by ER stress. Chrysin, a naturally occurring flavonoid, can be found abundantly in honey, propolis, and various plant extracts. Despite possessing advantageous attributes such as being an antioxidant, anti-allergic, anti-inflammatory, anti-fibrotic, and anticancer agent, chrysin exhibits limited bioavailability. The current study aimed to produce a more bioavailable form of chrysin and discover how administering chrysin could alter the neuropathy induced by Alloxan in male rats. METHODS: Chrysin was formulated using PEGylated liposomes to boost its bioavailability and formulation. Chrysin PEGylated liposomes (Chr-PLs) were characterized for particle size diameter, zeta potential, polydispersity index, transmission electron microscopy, and in vitro drug release. Rats were divided into four groups: control, Alloxan, metformin, and Chr-PLs. In order to determine Chr- PLs' antidiabetic activity and, by extension, its capacity to ameliorate DN, several experiments were carried out. These included measuring acetylcholinesterase, fasting blood glucose, insulin, genes dependent on autophagy or stress in the endoplasmic reticulum, and histopathological analysis. RESULTS: According to the results, the prepared Chr-PLs exhibited an average particle size of approximately 134 nm. They displayed even distribution of particle sizes. The maximum entrapment efficiency of 90.48 ± 7.75% was achieved. Chr-PLs effectively decreased blood glucose levels by 67.7% and elevated serum acetylcholinesterase levels by 40% compared to diabetic rats. Additionally, Chr-PLs suppressed the expression of ER stress-related genes (ATF-6, CHOP, XBP-1, BiP, JNK, PI3K, Akt, and mTOR by 33%, 39.5%, 32.2%, 44.4%, 40.4%, 39.2%, 39%, and 35.9%, respectively). They also upregulated the miR-301a-5p expression levels by 513% and downregulated miR-301a-5p expression levels by 65%. They also boosted the expression of autophagic markers (AMPK, ULK1, Beclin 1, and LC3-II by 90.3%, 181%, 109%, and 78%, respectively) in the sciatic nerve. The histopathological analysis also showed that Chr-PLs inhibited sciatic nerve degeneration. CONCLUSION: The findings suggest that Chr-PLs may be helpful in the protection against DN via regulation of ER stress and autophagy.
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Autofagia , Diabetes Mellitus Experimental , Neuropatias Diabéticas , Estresse do Retículo Endoplasmático , Flavonoides , Lipossomos , Animais , Flavonoides/farmacologia , Flavonoides/administração & dosagem , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Masculino , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Ratos , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/prevenção & controle , Polietilenoglicóis/farmacologia , Aloxano , Ratos Wistar , Ratos Sprague-DawleyRESUMO
INTRODUCTION: Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. Ischemic heart disease is one of the most harmful conditions to cellular structure and function. After reperfusion treatment, a spectrum of adverse effects becomes evident, encompassing altered cell viability, heightened oxidative stress, activated autophagy, and increased apoptosis. Photobiomodulation (PBM) has been utilized in experimental models of cardiac hypoxia to enhance mitochondrial response and ameliorate biochemical changes in injured tissue. However, the effects of PBM on cultured cardiomyocytes subjected to hypoxia/reoxygenation are not yet well established. METHOD: H9C2 cardiomyocytes were exposed to hypoxia with concentrations of 300 µM CoCl2 for 24 h, followed by 16 h of reoxygenation through incubation in a normoxic medium. Treatment was conducted using GaAIAs Laser (850 nm) after hypoxia at an intensity of 1 J/cm2. Cells were divided into three groups: Group CT (cells maintained under normoxic conditions), Group HR (cells maintained in hypoxia and reoxygenation conditions without treatment), Group HR + PBM (cells maintained in hypoxia and reoxygenation conditions that underwent PBM treatment). Cell viability was analyzed using MTT, and protein expression was assessed by western blot. One-way ANOVA with the Tukey post hoc test was used for data analysis. Differences were significant when p < 0.05. RESULTS: PBM at an intensity of 1 J/cm2 mitigated the alterations in cell survival caused by hypoxia/reoxygenation. Additionally, it significantly increased the expression of proteins Nrf2, HSP70, mTOR, LC3II, LC3II/I, and Caspase-9, while reducing the expression of PGC-1α, SOD2, xanthine oxidase, Beclin-1, LC3I, and Bax. CONCLUSION: PBM at intensities of 1 J/cm2 reverses the changes related to oxidative stress, mitochondrial biogenesis, autophagy, and apoptosis caused by hypoxia and reoxygenation in a culture of cardiomyocytes.