RESUMEN

The antitumor activity of DVL, a lectin purified from Dioclea violacea seeds, on the U87 human glioma cell line was evaluated and compared with Canavalia ensiformis lectin (ConA). Treatment with DVL (10-100 µg/mL; 24-96 h) induced alterations in cell morphology, decreased cell numbers and clonogenic survival in a time- and concentration-dependent manner. DVL caused significant decreases in cell viability and impaired cell migration. Mechanistically, DVL treatment (12 h) disrupted mitochondrial electrochemical gradient, without ROS accumulation or caspase activation. In the absence of apoptosis, DVL (30-100 µg/mL), instead, induced autophagy, as detected by acridine orange staining and cleavage of LC3I. Inhibition of autophagy with 3-Methyladenine (3-MA) and Chloroquine partially abrogated DVL, but not ConA, cytotoxicity. The modulation of signaling pathways that orchestrate autophagic and cell survival processes were analyzed. DVL (30-100 µg/mL) decreased Akt, mTORC1 and ERK1/2 phosphorylation and augmented JNK(p54) and p38MAPK phosphorylation. DVL was more potent than ConA for most parameters analyzed. Even though both lectins showed cytotoxicity to glioma cells, they spared primary astrocyte cultures. The results suggest a selective antiglioma activity of DVL by inhibiting U87 glioma cell migration and proliferation and inducing cell death, partially associated with autophagy, and likely involving Akt and mTORC1 dephosphorylation.

Asunto(s)

Autofagia/efectos de los fármacos , Dioclea/química , Lectinas de Plantas/farmacología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Glioma/genética , Glioma/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/aislamiento & purificación , Ratas , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos

RESUMEN

Inflammation of temporomandibular joint (TMJ) tissues are the most common cause of pain conditions associated with temporomandibular disorders (TMDs). After a tissue and/or neural damage, the inflammatory response is characterized by plasma extravasation and leukocytes infiltration in the TMJ tissues, which in turn, release inflammatory cytokines cascades responsible for inflammatory pain. Lectins are glycoproteins widely distributed in nature that may exhibit anti-inflammatory properties. This study demonstrated by molecular docking and MM/PBSA that the lectin from Dioclea violacea (DVL) interacts favorably with α-methyl-D-mannoside, N-acetyl-D-glucosamine, and core1-sialyl-Lewis X which are associated with leukocytes migration during an inflammatory response. Wistar rats pretreated with intravenously injection of DVL demonstrated a significant inhibition of plasma extravasation induced by carrageenan (a non-neurogenic inflammatory inductor) and mustard oil (a neurogenic inflammatory inductor) in the TMJ periarticular tissues (p < 0.05; ANOVA, Tukey's test). In addition, DVL significantly reduced carrageenan-induced leukocyte migration in the TMJ periarticular tissues mediated by down-regulation of ICAM-1 expression. These results suggest a potential anti-inflammatory effect of DVL in inflammatory conditions of TMJ.

Asunto(s)

Antiinflamatorios , Dioclea/química , Molécula 1 de Adhesión Intercelular/biosíntesis , Leucocitos/metabolismo , Lectinas de Plantas , Trastornos de la Articulación Temporomandibular/tratamiento farmacológico , Articulación Temporomandibular/metabolismo , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Movimiento Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Leucocitos/patología , Masculino , Simulación del Acoplamiento Molecular , Lectinas de Plantas/química , Lectinas de Plantas/farmacología , Ratas , Ratas Wistar , Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/inducido químicamente , Trastornos de la Articulación Temporomandibular/metabolismo , Trastornos de la Articulación Temporomandibular/patología

RESUMEN

Plant lectins have been studied owing to their structural properties and biological effects that include agglutinating activity, antidepressant-like effect and antitumor property. The results from this work showed the effects of the lectin extracted from the Dioclea violacea plant (DVL) on the C6 rat glioma cell line. DVL treatment was able to induce caspase-3 activation, apoptotic cell death and cellular membrane damage. Furthermore, DVL decreased mitochondrial membrane potential and increased the number of acidic vesicles and cleavage of LC3, indicating activation of autophagic processes. DVL also significantly inhibited cell migration. Compared to ConA, a well-studied lectin extracted from Canavalia ensiformes seeds, some effects of DVL were more potent, including decreasing C6 glioma cell viability and migration ability. Taken together, the results suggest that DVL can induce glioma cell death, autophagy and inhibition of cell migration, displaying potential anti-glioma activity.

Asunto(s)

Autofagia/efectos de los fármacos , Dioclea/química , Expresión Génica/efectos de los fármacos , Neuroglía/efectos de los fármacos , Lectinas de Plantas/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Autofagia/genética , Canavalia/química , Caspasa 3/genética , Caspasa 3/metabolismo , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Concanavalina A/aislamiento & purificación , Concanavalina A/farmacología , L-Lactato Deshidrogenasa/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neuroglía/metabolismo , Neuroglía/patología , Lectinas de Plantas/aislamiento & purificación , Ratas

RESUMEN

Entomotoxic plant lectins have been extensively studied in the past two decades, yet the exact mechanisms underlying their toxic effects remain unknown. This study investigated the effects of Dioclea violacea lectin (DVL) on larval development in Anagasta kuehniella. Chronic exposure of larvae (from neonates to the fourth instar) demonstrated that DVL interfered with larval growth, retarding development and decreasing larval mass without affecting survival. DVL decreased trypsin-like, chymotrypsin-like, and α-amylase activities and proved resistant to proteolysis by midgut proteases up to 24h. Shorter exposures to dietary DVL had no effect on midgut enzyme activity. Feeding fourth-instar larvae with fluorescently-labeled DVL revealed lectin binding to the peritrophic membrane.

Asunto(s)

Dioclea , Mariposas Nocturnas/enzimología , Lectinas de Plantas/metabolismo , Animales , Peso Corporal , Tracto Gastrointestinal/enzimología , Larva/efectos de los fármacos , Larva/enzimología , Larva/crecimiento & desarrollo , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/crecimiento & desarrollo , Lectinas de Plantas/toxicidad , Proteolisis

RESUMEN

Acute kidney injury (AKI) is characterized by rapid and potentially reversible decline in renal function; however, the current management for AKI is nonspecific and associated with limited supportive care. Considering the need for more novel therapeutic approaches, we believe that lectins from Dioclea violacea (Dvl), based on their anti-inflammatory properties, could be beneficial for the treatment of AKI induced by renal ischemia/reperfusion (IR). Dvl (1 mg/kg, i.v.) or vehicle (100 µL) was administered to Wistar rats prior to the induction of bilateral renal ischemia (45 min). Following 24 hours of reperfusion, inulin and para-aminohippurate (PAH) clearances were performed to determine glomerular filtration rate (GFR), renal plasma flow (RPF), renal blood flow (RBF) and renal vascular resistance (RVR). Renal inflammation was assessed using myeloperoxidase (MPO) activity. Kidney sections were stained with hematoxylin-eosin to evaluate morphological changes. Intracellular superoxide anions, hydrogen peroxide, peroxynitrite, nitric oxide and apoptosis were analyzed using flow cytometry. IR resulted in diminished GFR, RPF, RBF, and increased RVR; however, these changes were ameliorated in rats receiving Dvl. AKI-induced histomorphological changes, such as tubular dilation, tubular necrosis and proteinaceous casts, were attenuated by Dvl administration. Treatment with Dvl resulted in diminished renal MPO activity, oxidative stress and apoptosis in rats submitted to IR. Our data reveal that Dvl has a protective effect in the kidney, improving renal function after IR injury, probably by reducing neutrophil recruitment and oxidative stress. These results indicate that Dvl can be considered a new therapeutic approach for AKI-induced kidney injury.