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1.
J. bras. nefrol ; 46(1): 18-28, Mar. 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1534764

RESUMEN

Abstract Introduction: Nephrotic syndrome (NS) is one of the reasons of end-stage kidney disease, and elucidating the pathogenesis and offer new treatment options is important. Oxidative stress might trigger pathogenesis systemically or isolated in the kidneys. Octreotide (OCT) has beneficial antioxidant effects. We aimed to investigate the source of oxidative stress and the effect of OCT on experimental NS model. Methods: Twenty-four non-uremic Wistar albino rats were divided into 3 groups. Control group, 2 mL saline intramuscular (im); NS group, adriamycin 5 mg/kg intravenous (iv); NS treatment group, adriamycin 5 mg/kg (iv) and OCT 200 mcg/kg (im) were administered at baseline (Day 0). At the end of 21 days, creatinine and protein levels were measured in 24-hour urine samples. Erythrocyte and renal catalase (CAT) and thiobarbituric acid reactive substance (TBARS) were measured. Renal histology was also evaluated. Results: There was no significant difference among the 3 groups in terms of CAT and TBARS in erythrocytes. Renal CAT level was lowest in NS group, and significantly lower than the control group. In treatment group, CAT level significantly increased compared with NS group. In terms of renal histology, tubular and interstitial evaluations were similar in all groups. Glomerular score was significantly higher in NS group compared with control group and it was significantly decreased in treatment group compared to NS group. Conclusions: Oxidative stress in NS might be due to the decrease in antioxidant protection mechanism in kidney. Octreotide improves antioxidant levels and histology in renal tissue and might be a treatment option.


Resumo Introdução: Síndrome nefrótica (SN) é uma das causas de doença renal em estágio terminal. É importante elucidar a patogênese e oferecer novas opções de tratamento. Estresse oxidativo pode desencadear a patogênese sistemicamente ou isoladamente nos rins. O octreotide (OCT) tem efeitos antioxidantes benéficos. Nosso objetivo foi investigar a fonte de estresse oxidativo e efeito do OCT no modelo experimental de SN. Métodos: Dividimos 24 ratos albinos Wistar não urêmicos em 3 grupos. Grupo controle, 2 mL de solução salina intramuscular (im); grupo SN, adriamicina 5 mg/kg intravenosa (iv); grupo tratamento SN, adriamicina 5 mg/kg (iv) e OCT 200 mcg/kg (im) foram administrados no início do estudo (Dia 0). Aos 21 dias, mediram-se os níveis de creatinina e proteína em amostras de urina de 24 horas. Mediu-se a catalase (CAT) eritrocitária e renal e a substância reativa ao ácido tiobarbitúrico (TBARS). Avaliou-se também histologia renal. Resultados: Não houve diferença significativa entre os três grupos em termos de CAT e TBARS em eritrócitos. O nível de CAT renal foi menor no grupo SN e significativamente menor que no grupo controle. No grupo tratamento, o nível de CAT aumentou significativamente em comparação com o grupo SN. Quanto à histologia renal, as avaliações tubular e intersticial foram semelhantes em todos os grupos. O escore glomerular foi significativamente maior no grupo SN em comparação com o grupo controle e diminuiu significativamente no grupo de tratamento em comparação com o grupo SN. Conclusões: Estresse oxidativo na SN pode ser devido à diminuição do mecanismo de proteção antioxidante nos rins. O octreotide melhora níveis de antioxidantes e histologia do tecido renal e pode ser uma opção de tratamento.

2.
Acta Pharmaceutica Sinica ; (12): 643-650, 2024.
Artículo en Chino | WPRIM | ID: wpr-1016629

RESUMEN

Three carboline fluorescent probes F1-F3 were designed and synthesized, based on lead compound JYJ-19, an antifungal compound discovered previously by our group. The antifungal activity in vitro results showed that compound F1 had moderate antifungal activity (MIC80 = 32 μg·mL-1). The stokes shift of F1 is 70 nm. The fluorescent probe F1 has good optical properties and can be used for fluorescence imaging research. Subcellular localization experiments results showed that F1 was enriched in the mitochondria of fungal cells. The detection of intracellular reactive oxygen species levels shows that JYJ-19 enhances intracellular reactive oxygen species levels. The above results indicated that carboline compounds could exert antifungal effects by acting on fungal mitochondria.

3.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 257-265, 2024.
Artículo en Chino | WPRIM | ID: wpr-1013086

RESUMEN

Objective@#To investigate the effects of PssL-NAC reactive oxygen species (ROS)-responsive nanoparticles on intracellular ROS production, inflammatory factor levels, collagen production, cell function and Toll-like receptor 4 (TLR4), NF-κB nuclear factor-κB (p65) pathway protein expression in human gingival fibroblasts (HGFs) induced by Porphyromonas gingivalis-lipopolysaccharide (P.g-LPS).@*Methods@#This study was reviewed and approved by the ethics committee. PssL-NAC microspheres containing oil soluble antioxidant N-acetylcysteine (NAC) were obtained by connecting the hydrophobic end of polycaprolactone (PCL) and the hydrophilic end of polyethylene glycol (PEG) via thioketal (TK) bonds in response to ROS, and self loading in the aqueous and oil phases. After preparation of the PssL-NAC microspheres and aqueous NAC solution, successful synthesis of the nanoparticles was verified by transmission electron microscopy. Then, HGFs were exposed to P.g-LPS (0, 5, or 10 μg/mL), P.g-LPS (0, 5, or 10 μg/mL)+NAC, and P.g-LPS (0, 5, or 10 μg/mL)+PssL-NAC, and the ROS levels in the different groups were observed under confocal microscopy to determine the concentration of P.g-LPS for use in subsequent experiments. The groups were as follows: control group (no treatment), P.g-LPS group (HGFs treated with P.g-LPS), NAC group (HGFs treated with P.g-LPS and NAC), and PssL-NAC group (HGFs treated with P.g-LPS and PssL-NAC). Cell counting kit-8 (CCK-8) assays verified the biosafety of PssL-NAC. The ROS levels in the different groups were detected by DCFH-DA probes and observed via confocal microscopy. Real-time qPCR (RT-qPCR) was used to monitor the gene expression levels of the intracellular inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), collagen 1 (COL1) and collagen 3 (COL3). The effect of PssL-NAC on the migration of HGFs was observed via the scratch test. The protein expression of TLR4-NF-κB, and phosphorylated p65 (p-p65) in the TLR4-NF-κB pathway was evaluated by Western blot.@*Results@#PssL-NAC had no significant effect on HGF proliferation (P>0.05). At elevated P.g-LPS concentrations, PssL-NAC maintained intracellular ROS levels approximately twice those in the control group (P<0.001). PssL-NAC significantly decreased P.g-LPS-induced IL-6 (P<0.001) and TNF-α (P<0.001) gene expression and increased COL1 gene expression (P<0.001). After P.g-LPS stimulation, PssL-NAC restored cell migration to the control level (P>0.05) and decreased the protein expression of TLR4 (P<0.001), p65 (P = 0.006), and p-p65 (P = 0.017) in the TLR4-NF-κB pathway.@*Conclusion@#PssL-NAC maintains the appropriate intracellular ROS concentration, alleviates P.g-LPS-induced inflammation in HGFs through the TLR4-NF-κB pathway, and restores the cell functions of collagen production and migration in an inflammatory environment.

4.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 241-248, 2024.
Artículo en Chino | WPRIM | ID: wpr-1013084

RESUMEN

@#Oral plaque biofilms are one of the bases for the survival and metabolism of different bacteria. With the emergence of drug-resistant bacteria due to antibiotic abuse, the prevention and treatment of plaque biofilm-associated oral diseases are becoming increasingly difficult. Although some research progress has been made in the field of biofilm formation and destruction, there is still a lack of effective clinical therapies for plaque biofilm-associated oral diseases. Metal nanoenzymes possess the physical properties of nanoparticles and exhibit catalytic activity similar to that of natural enzymes. The nanoscale size of metal nanoenzymes provides a greater specific surface area to help reactive oxygen species spread rapidly to active catalytic sites and improve the antioxidant properties of nanoenzymes. Additionally, metal nanoenzymes are easy to produce using different methods, such as electrochemical reduction, solvent thermal synthesis and microwave-assisted synthesis. Moreover, metal nanoenzymes can produce a high concentration of hydroxyl radicals, catalyze plaque biofilm degradation, lyse glucan and inhibit biofilm formation by oxidative stress reactions, as well as kill bacteria by releasing metal ions. Thus, metal nanoenzymes are expected to become a new option for the prevention and treatment of oral plaque biofilm-associated diseases. However, metal nanoenzymes can enter organisms through oral, intravenous and respiratory routes, triggering potential toxic effects such as pulmonary toxicity, hepatotoxicity and neurotoxicity. In a complex biological environment, the occurrence of metal nanoenzymes toxicity may involve multiple mechanisms, and the mechanism of action and safety need to be thoroughly investigated. In this paper, we intend to describe the research progress on metal nanoenzymes through an overview of their properties, antibacterial mechanisms, biotoxicity and applications in the prevention and treatment of oral plaque biofilm-related diseases, which may provide new ideas for the prevention and treatment of these diseases.

5.
Acta Pharmaceutica Sinica B ; (6): 751-764, 2024.
Artículo en Inglés | WPRIM | ID: wpr-1011259

RESUMEN

Recent progress in targeted metabolic therapy of cancer has been limited by the considerable toxicity associated with such drugs. To address this challenge, we developed a smart theranostic prodrug system that combines a fluorophore and an anticancer drug, specifically 6-diazo-5-oxo-l-norleucine (DON), using a thioketal linkage (TK). This system enables imaging, chemotherapy, photodynamic therapy, and on-demand drug release upon radiation exposure. The optimized prodrug, DON-TK-BM3, incorporating cyanine dyes as the fluorophore, displayed potent reactive oxygen species release and efficient tumor cell killing. Unlike the parent drug DON, DON-TK-BM3 exhibited no toxicity toward normal cells. Moreover, DON-TK-BM3 demonstrated high tumor accumulation and reduced side effects, including gastrointestinal toxicity, in mice. This study provides a practical strategy for designing prodrugs of metabolic inhibitors with significant toxicity stemming from their lack of tissue selectivity.

6.
Organ Transplantation ; (6): 46-54, 2024.
Artículo en Chino | WPRIM | ID: wpr-1005233

RESUMEN

Objective To investigate the role and mechanism of spliced X-box binding protein 1 (XBP1s) in the senescence of primary renal tubular epithelial cells induced by hypoxia/reoxygenation (H/R). Methods Primary renal tubular epithelial cells were divided into the normal control group (NC group), H/R group, empty adenovirus negative control group (Ad-shNC group), targeted silencing XBP1s adenovirus group (Ad-shXBP1s group), empty adenovirus+H/R treatment group (Ad-shNC+H/R group) and targeted silencing XBP1s adenovirus+H/R treatment group (Ad-shXBP1s +H/R group), respectively. The expression levels of XBP1s in the NC, H/R, Ad-shNC and Ad-shXBP1s groups were measured. The number of cells stained with β-galactosidase, the expression levels of cell aging markers including p53, p21 and γH2AX, and the levels of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) were determined in the Ad-shNC, Ad-shNC+H/R and Ad-shXBP1s+H/R groups. Chromatin immunoprecipitation was employed to verify Sirtuin 3 (Sirt3) of XBP1s transcription regulation, and the expression levels of Sirt3 and downstream SOD2 after down-regulation of XBP1s were detected. Mitochondrial reactive oxygen species (mtROS) were detected by flow cytometry. Results Compared with the NC group, the expression level of XBP1s was up-regulated in the H/R group. Compared with the Ad-shNC group, the expression level of XBP1s was down-regulated in the Ad-shXBP1s group (both P<0.001). Compared with the Ad-shNC group, the number of cells stained with β-galactosidase was increased, the expression levels of p53, p21 and γH2AX were up-regulated, the levels of ROS, MDA and mtROS were increased, the SOD activity was decreased, the expression level of Sirt3 was down-regulated, and the ratio of Ac-SOD2/SOD2 was increased in the Ad-shNC+H/R group. Compared with the Ad-shNC+H/R group, the number of cells stained with β-galactosidase was decreased, the expression levels of p53, p21 and γH2AX were down-regulated, the levels of ROS, MDA and mtROS were decreased, the SOD activity was increased, the expression level of Sirt3 was up-regulated and the ratio of Ac-SOD2/SOD2 was decreased in the Ad-shXBP1s+H/R group (all P<0.05). Conclusions Down-regulation of XBP1s may ameliorate the senescence of primary renal tubular epithelial cells induced by H/R, which probably plays a role through the Sirt3/SOD2/mtROS signaling pathway.

7.
Organ Transplantation ; (6): 40-45, 2024.
Artículo en Chino | WPRIM | ID: wpr-1005232

RESUMEN

Ischemia-reperfusion injury (IRI) is an extremely complicated pathophysiological process, which may occur during the process of myocardial infarction, stroke, organ transplantation and temporary interruption of blood flow during surgery, etc. As key molecules of immune system, macrophages play a vital role in the pathogenesis of IRI. M1 macrophages are pro-inflammatory cells and participate in the elimination of pathogens. M2 macrophages exert anti-inflammatory effect and participate in tissue repair and remodeling and extracellular matrix remodeling. The balance between macrophage phenotypes is of significance for the outcome and treatment of IRI. This article reviewed the role of macrophages in IRI, including the balance between M1/M2 macrophage phenotype, the mechanism of infiltration and recruitment into different ischemic tissues. In addition, the potential therapeutic strategies of targeting macrophages during IRI were also discussed, aiming to provide reference for alleviating IRI and promoting tissue repair.

8.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 95-102, 2024.
Artículo en Chino | WPRIM | ID: wpr-999165

RESUMEN

ObjectiveTo explore the mechanism of Buzhong Yiqitang-containing serum in alleviating the cisplatin resistance in human non-small cell lung cancer (A549/DDP) cells via regulating the nuclear factor E2-related factor 2 (Nrf2)/reactive oxygen species (ROS) signaling pathway. MethodThe serum containing Buzhong Yiqitang was prepared and A549/DDP cells were cultured and randomly grouped: blank (10% blank serum), cisplatin (10% blank serum+20 mg·L-1 cisplatin), Buzhong Yiqitang (10% Buzhong Yiqitang-containing serum+20 mg·L-1 cisplatin), ML385 (10% blank serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin), Buzhong Yiqitang+ML385 (10% Buzhong Yiqitang-containing serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin), tertiary butylhydroquinone (TBHQ) (10% blank serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin), and Buzhong Yiqitang+TBHQ (10% Buzhong Yiqitang-containing serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin). The median inhibitory concentration (IC50) of cisplatin in each group was determined by the cell counting kit-8 (CCK-8) method and the resistance index (RI) was calculated. The apoptosis rate was detected by flow cytometry. The ROS content of each group was determined with the DCFH-DA fluorescence probe. Western blot was employed to determine the protein levels of Nrf2, cleaved cysteinyl aspartate-specific protease-3 (cleaved Caspase-3), cytochrome C (Cyt C), and B-cell lymphoma-2 (Bcl-2). ResultCompared with those in the cisplatin group, the IC50 and RI of A549/DDP cells to cisplatin in Buzhong Yiqitang, ML385, and Buzhong Yiqitang+ML385 groups decreased (P˂0.05). Compared with the blank group, the cisplatin, Buzhong Yiqitang, ML385, and Buzhong Yiqitang+ML385 groups showed increased apoptosis rate of A549/DDP cells (P˂0.05). Compared with the blank group, cisplatin promoted the expression of Nrf2 (P˂0.05). Compared with the cisplatin group, Buzhong Yiqitang, ML385, and Buzhong Yiqitang+ML385 inhibited the expression of Nrf2 (P<0.05), elevated the ROS level (P˂0.05), up-regulated the protein levels of cleaved Caspase-3 and Cyt C, and down-regulated the protein level of Bcl-2 (P<0.05), which were the most significant in the Buzhong Yiqitang+ML385 group. Compared with the cisplatin group, the TBHQ group showed increased IC50 and RI of cisplatin (P<0.05), decreased apoptosis rate of A549/DDP cells (P<0.05), up-regulated protein levels of Nrf2 and Bcl-2 (P<0.05), lowered level of ROS (P˂0.05), and down-regulated protein levels of cleaved Caspase-3 and Cyt C (P<0.05). Compared with the TBHQ group, Buzhong Yiqitang+TBHQ decreased the IC50 and RI of cisplatin in A549/DDP cells (P<0.05), increased the apoptosis rate (P<0.05), down-regulated the protein levels of Nrf2 and Bcl-2 (P<0.05), increased ROS (P˂0.05), and up-regulated the protein levels of cleaved Caspase-3 and Cyt C (P<0.05). ConclusionBuzhong Yiqitang induced apoptosis by inhibiting Nrf2/ROS pathway to alleviate cisplatin resistance in A549/DDP cells.

9.
Rev. chil. nutr ; 50(6)dic. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1550795

RESUMEN

Oxidative stress (OS) occurs when the antioxidant defense system is overwhelmed by the predominance of reactive oxygen species (ROS) and pro-oxidant factors. Several diseases such as hypertension, insulin resistance, type 2 diabetes mellitus and neurodegenerative diseases are characterized by chronic OS. Physical exercise constitutes an affordable tool to prevent or ameliorate these conditions. However, during physical activity, acute ROS are produced inducing an activation in peroxisome proliferator activated receptor-Gamma Coactivator-1alpha (PGC-1α), and nuclear factor erythroid-2 related factor 2 (Nrf2), PGC-1α/Nrf2 pathway. This signaling pathway facilitates interaction with antioxidant response elements (ARE), thereby initiating an upregulation in the expression of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and mitochondrial biogenesis. In both cases, whether involving healthy animals or individuals engaged in physical exercise, supplementation with antioxidant scavengers leads to a reduction in the expression and activity of PGC-1α, SOD, CAT, and GPX across various tissues, which is not observed with indirect antioxidants. The preventive role of physical exercise against chronic OS is avoided when executed in conjunction with supplementation of scavenger antioxidants. However, similar to exercise, the indirect antioxidant apigenin can activate the PGC1-α/Nrf2 signaling pathway. Here, we summarize evidence supporting apigenin as a non-nutritional supplement that could enhance the adaptive effects of exercise, improving the endogenous antioxidant defense. Therefore, apigenin could be an interesting supplement to enhance the endogenous antioxidant adaptation induced by exercise in healthy subjects, but also to improve the effectiveness of exercise to prevent oxidative stress-associated diseases.


El estrés oxidativo (OS) ocurre cuando el sistema de defensa antioxidante es sobrepasado por el predominio de especies reactivas de oxígeno (ROS) y factores prooxidantes. Varias enfermedades como la hipertensión, la resistencia a la insulina, la diabetes mellitus tipo 2 y enfermedades neurodegenerativas se caracterizan por un OS crónico. El ejercicio físico constituye una herramienta asequible para prevenir o mejorar estas enfermedades. Sin embargo, durante la actividad física, se producen ROS agudas que inducen una activación en la vía PGC-1α/Nrf2. Esta vía de señalización facilita la interacción con los elementos de respuesta antioxidante (ARE), iniciando así una regulación que permite la expresión de enzimas antioxidantes, incluidas SOD, CAT, GPX y biogénesis mitocondrial. En ambos casos, ya sea que se trate de animales sanos o de individuos que practican ejercicio físico, la suplementación con antioxidantes "scavengers" conduce a una reducción en la expresión y actividad de PGC-1α, SOD, CAT y GPX en varios tejidos, lo que no se observa con antioxidantes "indirectos". El papel preventivo del ejercicio físico contra el OS crónico se atenúa cuando se realiza en conjunto con la suplementación de antioxidantes "scavengers". Sin embargo, de manera similar al ejercicio, la apigenina es un antioxidante "indirecto" que puede activar la vía de señalización PGC1-α/Nrf2. Aquí, resumimos la evidencia que respalda a apigenina como un suplemento no-nutricional que podría mejorar los efectos adaptativos del ejercicio, mejorando la defensa antioxidante endógena de sujetos sanos que no tienen suficiente tiempo para hacer ejercicio.

10.
Indian J Physiol Pharmacol ; 2023 Jun; 67(2): 131-135
Artículo | IMSEAR | ID: sea-223989

RESUMEN

Objectives: Radiofrequency electromagnetic radiation (RF-EMR) from mobile phones is known to produce a stress response because of its effect on hypothalamus. Mobile phones have become an integral part of our lives with increasing usage not only in terms of number of users but also increase in talk time. The present study aimed to study the effect of mobile phone radiofrequency electromagnetic radiations on oxidative stress and feeding behaviour assessment in Sprague Dawley (SD) rats. Materials and Methods: Twelve male SD rats of 10–12 weeks old, weighing 180–220 g, were housed and allowed to acclimatise in a room with 12:12 h light-dark cycle with ad libitum amount of food and reverse osmosis (RO) water before the start of the study. Then, rats were divided into control and RF-EMR exposed groups, and everyday feed intake and body weight were measured. At the end of the study period, blood sample was collected through retro orbital puncture for biochemical investigations. Results: The present study showed significant increase in malondialdehyde and serum corticosterone levels and decrease feeding behaviour in rats exposed to RF-EMR in rats exposed to RF-EMR. Conclusion: This study proves that mobile RF-EMR causes oxidative stress and oxidative damage leading to decreased feeding behaviour in SD rats.

11.
Horiz. meÌüd. (Impresa) ; 23(2)abr. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1440192

RESUMEN

Los radicales libres son compuestos caracterizados por tener un electrón desapareado en su orbital externo, condición que los torna altamente reactivos, es decir, tienen la propiedad de interactuar a través de reacciones controladas por difusión con proteínas, lípidos y ácidos nucleicos. También se les ha designado como especies reactivas de oxígeno (ERO), especies reactivas de nitrógeno (ERN) o especies reactivas de azufre (ERA). En el organismo humano se generan, principalmente, en la cadena transportadora de electrones mitocondrial, donde específicamente participan los complejos respiratorios I y III que tienen la propiedad de reducir al oxígeno y convertirlo en anión superóxido; así mismo, pueden formarse haciendo uso de una gran diversidad de reacciones enzimáticas y no enzimáticas en las que intervienen sustancias que la célula sintetiza o que se ingieren con los alimentos y algunos medicamentos. El ser humano dispone de un sistema antioxidante, que es de naturaleza enzimática y no enzimática, el cual tiene como función proteger al organismo de la acción nociva de los radicales libres; comprende enzimas -como catalasa, superóxido dismutasa, tiorredoxina, etc.- y compuestos no enzimáticos -como glutatión, ferritina, mioglobina, etc.-, pero no son lo suficientemente eficientes para protegerlo, por lo que es necesaria la ingesta de alimentos que contengan en su composición sustancias con propiedades antioxidantes cuya acción protectora dependerá de su reactividad química, así como de su concentración; estos compuestos antioxidantes se encuentran principalmente en las frutas y verduras, habiéndose identificado polifenoles, flavonoides, carotenoides, vitamina C, vitamina E, etc. Un número considerable de evidencias sugiere que la ingesta de sustancias antioxidantes protege al organismo del efecto dañino de los radicales libres, pero cuando prevalece la acción oxidante sobre la antioxidante puede conducirse al estrés oxidativo, condición que está estrechamente vinculada con una gran diversidad de enfermedades crónicas no transmisibles como cáncer, diabetes mellitus, obesidad, psoriasis, aterosclerosis, entre otras. Todo ello parece indicar que el término "estado estable redox celular" describe de manera apropiada la constante adaptación a una situación de rápido recambio químico, y sugiere que las sustancias implicadas en este proceso se designen como "especies biológicamente reactivas" en razón de la existencia de compuestos nocivos como el peróxido de hidrógeno, peroxinitrito, etc., que no son propiamente radicales libres, pero ejercen efectos dañinos a las células.


Free radicals are compounds characterized by having an unpaired electron in their outer orbit, a condition that makes them highly reactive, i.e., they interact through diffusion-controlled reactions with proteins, lipids and nucleic acids. They have also been referred to as reactive oxygen species (ROS), reactive nitrogen species (RNS) or reactive sulfur species (RSS). In the human organism, they are mainly produced in the mitochondrial electron transport chain, where respiratory complexes I and III specifically participate and reduce oxygen by converting it into superoxide anion. Likewise, they can be formed through a wide variety of enzymatic and non-enzymatic reactions involving substances that are synthesized by cells or are ingested with food and some medicines. Human beings have an antioxidant system which is both enzymatic and non-enzymatic in nature and whose function is to protect the organism from the harmful action of free radicals. This system includes enzymes-such as catalase, superoxide dismutase, thioredoxin, etc.-and non-enzymatic compounds- such as glutathione, ferritin, myoglobin, etc. However, they are not efficient enough to protect it, so it is necessary to eat foods that contain substances with antioxidant properties whose protective action will depend on their chemical reactivity and their concentration. These antioxidant compounds are mainly found in fruits and vegetables, where polyphenols, flavonoids, carotenoids, vitamin C, vitamin E, etc. have been identified. A significant amount of evidence suggests that the intake of antioxidant substances protects the body from the damaging effect of free radicals, but when the oxidative action prevails over the antioxidant action, it can lead to oxidative stress, a condition that is closely linked to a wide variety of chronic non-communicable diseases including cancer, diabetes mellitus, obesity, psoriasis, atherosclerosis, among others. All this seems to indicate that the term "cellular redox steady state" more appropriately describes the constant adaptation to a situation of rapid chemical turnover and suggests that the substances involved in this process be designated as "biologically reactive species" due to the existence of harmful compounds such as hydrogen peroxide, peroxynitrite, etc., which are not-strictly speaking-free radicals but have toxic effects on cells.

12.
Chinese Journal of Biochemistry and Molecular Biology ; (12): 991-999, 2023.
Artículo en Chino | WPRIM | ID: wpr-1015621

RESUMEN

Drought is a common limiting factor affecting rice yield and quality. Cerium oxide nanoparticles(nanoceria) have been widely reported to improve crop stress tolerance. However, the effects and mechanisms of nanoceria on rice drought tolerance are still unknown. The aim of this study is to investigate whether nanoceria can improve rice drought tolerance by modulating reactive oxygen species(ROS) homeostasis and nitric oxide(NO) levels. Our results showed that compared with no-nanoparticle treatment, nanoceria significantly increased the fresh weight of rice seedlings under drought stress(19%, P < 0. 05). Also, under drought stress, the ROS level of rice leaves treated with nanoceria was significantly lower(82%, P < 0. 05) than leaves treated with buffer. The leaf NO level after nanoceria treatment, however, is significantly higher(46%, P < 0. 05) than that with no-nanoparticle treatment under drought stress. Moreover, compared with control plants, nanoceria maintained better membrane integrity in rice leaf cells under drought stress, showing a 70% decrease(P < 0. 05) in dead leaf cells. This study explores the mechanisms underlying nanoceria’s improved rice drought tolerance by affecting ROS and NO levels, which not only further enriches our knowledge about the interaction between nanoparticles and crops under abiotic stress but also gives more support on the sustainable development of nano-enabled agriculture.

13.
Chinese Journal of Biochemistry and Molecular Biology ; (12): 951-960, 2023.
Artículo en Chino | WPRIM | ID: wpr-1015610
14.
Chinese Journal of Biochemistry and Molecular Biology ; (12): 911-919, 2023.
Artículo en Chino | WPRIM | ID: wpr-1015609

RESUMEN

Oxidative stress is a state of redox imbalance, and it easily leads to oxidative damage in an organism. The main mechanism of oxidative stress is to regulate the redox balance by activating the antioxidant system. As an important signaling molecule, hydrogen sulfide(H

15.
Acta Pharmaceutica Sinica B ; (6): 4591-4606, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1011184

RESUMEN

Although carbon monoxide (CO)-based treatments have demonstrated the high cancer efficacy by promoting mitochondrial damage and core-region penetrating ability, the efficiency was often compromised by protective autophagy (mitophagy). Herein, cannabidiol (CBD) is integrated into biomimetic carbon monoxide nanocomplexes (HMPOC@M) to address this issue by inducing excessive autophagy. The biomimetic membrane not only prevents premature drugs leakage, but also prolongs blood circulation for tumor enrichment. After entering the acidic tumor microenvironment, carbon monoxide (CO) donors are stimulated by hydrogen oxide (H2O2) to disintegrate into CO and Mn2+. The comprehensive effect of CO/Mn2+ and CBD can induce ROS-mediated cell apoptosis. In addition, HMPOC@M-mediated excessive autophagy can promote cancer cell death by increasing autophagic flux via class III PI3K/BECN1 complex activation and blocking autolysosome degradation via LAMP1 downregulation. Furthermore, in vivo experiments showed that HMPOC@M+ laser strongly inhibited tumor growth and attenuated liver and lung metastases by downregulating VEGF and MMP9 proteins. This strategy may highlight the pro-death role of excessive autophagy in TNBC treatment, providing a novel yet versatile avenue to enhance the efficacy of CO treatments. Importantly, this work also indicated the applicability of CBD for triple-negative breast cancer (TNBC) therapy through excessive autophagy.

16.
Acta Pharmaceutica Sinica B ; (6): 3906-3918, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1011143

RESUMEN

Alcoholic liver disease (ALD) results from continuous and heavy alcohol consumption. The current treatment strategy for ALD is based on alcohol withdrawal coupled with antioxidant drug intervention, which is a long process with poor efficacy and low patient compliance. Alcohol-induced CYP2E1 upregulation has been demonstrated as a key regulator of ALD, but CYP2E1 knockdown in humans was impractical, and pharmacological inhibition of CYP2E1 by a clinically relevant approach for treating ALD was not shown. In this study, we developed a RNAi therapeutics delivered by lipid nanoparticle, and treated mice fed on Lieber-DeCarli ethanol liquid diet weekly for up to 12 weeks. This RNAi-based inhibition of Cyp2e1 expression reduced reactive oxygen species and oxidative stress in mouse livers, and contributed to improved ALD symptoms in mice. The liver fat accumulation, hepatocyte inflammation, and fibrosis were reduced in ALD models. Therefore, this study suggested the feasibility of RNAi targeting to CYP2E1 as a potential therapeutic tool to the development of ALD.

17.
Chinese Acupuncture & Moxibustion ; (12): 1287-1292, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1007474

RESUMEN

OBJECTIVES@#To explore the possible mechanism of Shao's five-needle therapy pretreatment on relieving airway inflammatory response in asthmatic rats.@*METHODS@#Forty SPF-grade SD rats were randomly divided into a blank group, a model group, an acupuncture group, and a medication group, with 10 rats in each group. Except the blank group, asthma model was established by aerosol inhalation of ovalbumin in the other 3 groups. The rats in the acupuncture group were treated with acupuncture at "Dazhui" (GV 14) and bilateral "Feishu" (BL 13) and "Fengmen" (BL 12), with each session lasting for 20 min. Acupuncture was given before each motivating, once daily for 7 consecutive days. The rats in the medication group were treated with intraperitoneal injection of dexamethasone sodium phosphate solution before each motivating, once daily for 7 days. General situation of the rats was observed in each group; ELISA method was used to detect the levels of inflammatory cytokines interleukin (IL)-1β and IL-18 in serum; immunofluorescence staining method was performed to assess the expression of reactive oxygen species (ROS) in lung tissues; Western blot method was used to measure the protein expression of thioredoxin interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 in lung tissues.@*RESULTS@#The rats in the blank group exhibited normal behavior, while those in the model group showed signs of respiratory distress, ear scratching, cheek rubbing, and dysphoria. Compared with the model group, the rats in the acupuncture group and the medication group showed stable respiration and relatively agile responses. Compared with those in the blank group, the serum levels of IL-18 and IL-1β were elevated (P<0.01), the expression intensity of ROS was increased, and the protein expressions of TXNIP, NLRP3, ASC and Caspase-1 in lung tissues were increased (P<0.01) in the model group. Compared with those in the model group, the serum levels of IL-18 and IL-1β were reduced (P<0.01), the expression intensity of ROS was lowered, and the protein expressions of TXNIP, NLRP3, ASC and Caspase-1 in lung tissues were reduced (P<0.01) in the acupuncture group and the medication group. Compared with the medication group, the protein expression of ASC in lung tissue was reduced in the acupuncture group (P<0.05).@*CONCLUSIONS@#Pretreatment of Shao's five-needle therapy could alleviate airway inflammatory response in asthmatic rats by reducing ROS levels and decreasing the aggregation and activation of pathway-related proteins in the ROS/TXNIP/NLRP3 pathway, ultimately leading to decreased secretion of IL-1β and IL-18. This mechanism may contribute to the effectiveness of Shao's five-needle therapy in preventing and treating asthma.


Asunto(s)
Ratas , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Interleucina-18/metabolismo , Proteínas NLR , Ratas Sprague-Dawley , Asma/metabolismo , Caspasas , Proteínas de Ciclo Celular
18.
Journal of Xi'an Jiaotong University(Medical Sciences) ; (6): 866-872, 2023.
Artículo en Chino | WPRIM | ID: wpr-1005767

RESUMEN

【Objective】 Diabetic mice could show learning and memory dysfunction, and we aimed to investigate the effect of Sigma-1 receptor agonist, PRE-084, on neurons and cognitive impairment in mice with type 1 diabetes (T1DM). 【Methods】 Twenty mice with T1DM induced by streptozocin, aged 8-10 weeks, and 20 control mice (CON) were randomly divided into four groups (CON+Vehicle, CON+PRE-084, T1DM+Vehicle and T1DM+PRE-084). Mouse primary neurons were cultured in high glucose medium with PRE-084 and control solvent, respectively. The body weight, food and water intake, and fasting blood glucose level of mice in each group were detected and recorded. The learning and memory abilities of mice were detected by new object recognition experiment. The mitochondria-associated endoplasmic reticulum membrane (MAM) structure of neurons in hippocampal CA1 area of mice was detected by transmission electron microscope. And the expression levels of ATP and reactive oxygen species (ROS) in hippocampus of mice were detected by biochemical kit. Cell viability and ROS level of primary neurons were detected by CCK8 and cellular ROS kit. 【Results】 PRE-084 reduced the increase of body weight, food and water intake, and blood glucose caused by diabetes. PRE-084 significantly ameliorated the learning and memory impairment of the mice with T1DM, improved the changes of MAM structure in neurons of hippocampal CA1 area of diabetic mice, increased the level of ATP in hippocampus of diabetic mice, and decreased the increase of ROS expression in diabetic hippocampus and neurons under high glucose conditions. 【Conclusion】 Sigma-1 receptor agonist, PRE-084, could improve learning and memory impairment in the mice with T1DM, which might be related to the structural changes of MAM, the increase of ATP production, and the decrease of ROS production in hippocampal neurons.

19.
Journal of Clinical Hepatology ; (12): 1454-1460, 2023.
Artículo en Chino | WPRIM | ID: wpr-978807

RESUMEN

Liver fibrosis is a compensatory response in the process of tissue repair after chronic liver injury, and it is also a necessary pathological process in the progression of a variety of chronic liver diseases. In the pathological state, the imbalance between hepatic oxidative system and antioxidant system can lead to the excessive production or insufficient clearance of reactive oxygen species (ROS)/reactive nitrogen species (RNS), which may induce the injury of hepatocytes, expand inflammatory response, and promote the development and progression of liver fibrosis. As a master regulator of oxidative stress and inflammatory response, NF-κB plays a key role in the process of liver fibrosis. Therefore, the cascade interaction between ROS/RNS and the NF-κB signaling pathway plays a guiding role in further clarifying the pathogenesis of liver fibrosis and exploring effective prevention and treatment strategies. This article reviews and discusses the interaction between ROS/RNS and the NF-κB signaling pathway and its important role in the progression of liver fibrosis, so as to provide strategies and references for targeted therapy for liver fibrosis.

20.
Acta Pharmaceutica Sinica ; (12): 891-898, 2023.
Artículo en Chino | WPRIM | ID: wpr-978765

RESUMEN

The bactericidal mechanism of carbon monoxide (CO) and the feasibility of CO-releasing molecules as anti-infective drugs were summarized by consulting scientific literature, combined with our own research work. Anaerobic bacteria are usually tolerant to high concentration of CO, and some can even grow with CO as sole carbon or energy source, but most pathogenic bacteria are sensitive to CO. In view of the difficulty of gaseous CO in controlling the applying dose and the action site, CO release molecules were synthesized. CO release molecules not only have higher bactericidal activities against common pathogenic bacteria than gaseous CO, but also have the ability to kill antibiotics-resistant bacteria and destroy their biofilms. CO mainly binds with heme-Fe2+ in cells, interrupting the electron transfer of respiration chains, which would result in the generation of reactive oxygen species. CO can also disturb intracellular ion balance, which further triggers free radical reactions. Due to its diverse acting targets, uneasy to induce drug resistance, and synergistic effect with other antibiotics, CO is expected to be the next generation of anti-infection drugs.

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