3 research outputs found
Hyperforin Elicits Cytostatic/Cytotoxic Activity in Human Melanoma Cell Lines, Inhibiting Pro-Survival NF-κB, STAT3, AP1 Transcription Factors and the Expression of Functional Proteins Involved in Mitochondrial and Cytosolic Metabolism
No full textHyperforin (HPF), the main component responsible for the antidepressant action of Hypericum perforatum, displays additional beneficial properties including anti-inflammatory, antimicrobic, and antitumor activities. Among its antitumor effects, HPF activity on melanoma is poorly documented. Melanoma, especially BRAF-mutated melanoma, is still a high-mortality tumor type and the currently available therapies do not provide solutions. We investigated HPF’s antimelanoma effectiveness in A375, FO1 and SK-Mel-28 human BRAF-mutated cell lines. Cell viability assays documented that all melanoma cells were affected by low HPF concentrations (EC50% 2–4 µM) in a time-dependent manner. A Br-deoxy-uridine incorporation assay attested a significant reduction of cell proliferation accompanied by decreased expression of cyclin D1 and A2, CDK4 and of the Rb protein phosphorylation, as assessed by immunoblots. In addition, the expression of P21/waf1 and the activated form of P53 were increased in A375 and SK-Mel-28 cells. Furthermore, HPF exerts cytotoxic effects. Apoptosis is induced 24 h after HPF administration, documented by an increase of cleaved-PARP1 and a decrease of both Bcl2 and Bcl-xL expression levels. Autophagy is induced, attested by an augmented LC3B expression and augmentation of the activated form of AMPK. Moreover, HPF lowers GPX4 enzyme expression, suggesting ferroptosis induction. HPF has been reported to activate the TRPC6 Ca++ channel and/or Ca++ and Zn++ release from mitochondria stores, increasing cytosolic Ca++ and Zn++ concentrations. Our data highlighted that HPF affects many cell-signaling pathways, including signaling induced by Ca++, such as FRA1, pcJun and pCREB, the expression or activity of which are increased shortly after treatment. However, the blockage of the TRPC6 Ca++ channel or the use of Ca++ and Zn++ chelators do not hinder HPF cytostatic/cytotoxic activity, suggesting that damages induced in melanoma cells may pass through other pathways. Remarkably, 24 h after HPF treatment, the expression of activated forms of the transcription factors NF-κB P65 subunit and STAT3 are significantly lowered. Several cytosolic (PGM2, LDHA and pPKM2) and mitochondrial (UQCRC1, COX4 and ATP5B) enzymes are downregulated by HPF treatment, suggesting a generalized reduction of vital functions in melanoma cells. In line with these results is the recognized ability of HPF to affect mitochondrial membrane potential by acting as a protonophore. Finally, HPF can hinder both melanoma cell migration and colony formation in soft agar. In conclusion, we provide evidence of the pleiotropic antitumor effects induced by HPF in melanoma cells
In vitro antitumor activity of Hyperforin in A375, FO1 and SKMEL-28 human melanoma cell lines
No full textnoneGli effetti antitumorali dell'iperforina rispetto al suo uso più tradizionale come antidepressivo sono stati appena esplorati nelle cellule di melanoma. I farmaci esistenti nel trattamento del melanoma sono scarsamente efficaci, in particolare del melanoma BRAF-mutato, che continua ad essere un tipo maligno con un alto tasso di mortalità. In questo studio, abbiamo esaminato l'attività antitumorale dell'iperforina nelle linee cellulari di melanoma umano A375, FO1 e SKMEL-28 che presentano la mutazione BRAF. È stato dimostrato che la vitalità cellulare del melanoma è influenzata negativamente dall'iperforina in modo tempo dipendente (EC50% 2-4 μM, dopo 72 ore). L'esperimento di incorporazione di Br-deossi-Uridina ha dimostrato una significativa diminuzione dei tassi di proliferazione cellulare, che è stata accompagnata da una minore produzione di ciclina D1 e A2, CDK4 e la proteina Rb fosforilata, come determinato dagli immunoblot. Le cellule A375 e SKMEL-28 hanno anche mostrato una maggiore espressione di p21/waf1 e la forma attivata di p53. Dopo 24 ore di trattamento con iperforina, i livelli di PARP1 tagliata sono aumentati mentre i livelli di espressione di Bcl-2 e Bcl-xL sono diminuiti, indicando che l'apoptosi era stata attivata. Un'aumentata espressione di LC3B e la forma attivata di AMPK indicavano entrambi che l'autofagia era stata avviata. L'iperforina abbassa l'espressione dell'enzima GPX4, suggerendo anche l'induzione della ferroptosi. Infine, il trattamento con iperforina ha portato alla downregulation di diversi enzimi citosolici (PGM2, LDHA e pPKM2) e mitocondriali (UQCRC1, COX4 e ATP5B), suggerendo una perdita diffusa delle funzioni metaboliche critiche nelle cellule di melanoma. Questi risultati potrebbero essere supportati dalla nota capacità dell'iperforina di abbassare il potenziale della membrana mitocondriale funzionando come un protonoforo. È stato inoltre dimostrato che l'iperforina potrebbe ostacolare sia la migrazione delle cellule di melanoma che la formazione di colonie nell'agar. Si può concludere che l'iperforina è in grado di contrastare la progressione del melanoma mediante effetti antitumorali pleiotropici.The antitumour effects of hyperforin compared to its more traditional use as an antidepressant has barely been explored in melanoma cells. The existing medicines in the treatment of melanoma are poorly effective, particularly of BRAF-mutated melanoma, which continues to be a malignant type with a high fatality rate. In this study, we examined the antitumour activity of hyperforin in human melanoma cell lines A375, FO1, and SKMEL-28 harbouring BRAF mutation. Melanoma cell viability was shown to be adversely affected by hyperforin in a time-dependent manner (EC50% 2-4 μM, after 72 hours). The Br-deoxy-Uridine incorporation experiment demonstrated a significant decrease in cell proliferation rates, which was accompanied by lower production of cyclin D1 and A2, CDK4, and Rb protein phosphorylation, as determined by immunoblots. A375 and SKMEL-28 cells also showed enhanced expression of p21/waf1 and the activated form of p53. After 24 hours of hyperforin treatment, cleaved-PARP1 levels rose while Bcl-2 and Bcl-xL expression levels fell, indicating that apoptosis had been activated. An increased expression of LC3B and the activated form of AMPK both indicated that autophagy was initiated. Hyperforin lowers GPX4 enzyme expression, suggesting ferroptosis induction, as well. Finally, hyperforin treatment resulted in the downregulation of several cytosolic (PGM2, LDHA, and pPKM2) and mitochondrial (UQCRC1, COX4, and ATP5B) enzyme expression, suggesting a widespread loss of critical metabolic functions in melanoma cells. These findings could be supported by hyperforin’s known capability to lower mitochondrial membrane potential by functioning as a protonophore. It was also demonstrated that hyperforin could hinder both melanoma cell migration and colony formation in soft agar.
It can be concluded that hyperforin is able to counteract melanoma progression by pleiotropic antitumour effects
INVESTIGATING MAGNETIC CONTROLLED REACTOR PRINCIPLES AND CHARACTERISTICS UTILIZING ANSYS IN AN IN-DEPTH STUDY
No full textThe inherent complexity leads to intricate equations, making it challenging for design engineers and researchers to model and analyze MCRs effectively. Despite the increasing attention given to MCRs in power systems, the need for simplified theoretical foundations and design models persists. This paper addresses the challenges posed by the complex excitation conditions of magnetic controlled reactors (MCRs), which are subject to both alternating current and direct current excitations by presenting the theoretical basis, ontological structure, working principle, and design model of MCRs in a systematic manner for enhanced comprehension. Graphical and equivalent electric circuit approaches are employed to derive mathematical expressions, while ANSYS simulation is utilized to create a 3D structure model of the MCR. The simulation results, compared with theoretical analyses, demonstrate that the MCR exhibits alternate magnetization and demagnetization between its two core limbs in a cycle. This suggests that the magnetic valves on both sides alternate between saturation and unsaturation in each cycle. Furthermore, the research reveals that the MCR’s entire capacity can be smoothly adjusted by varying the saturation degree of the magnetic valve core. Overall, this research contributes to a deeper understanding of MCRs under actual operating conditions and serves as a crucial foundation for further investigations into their performance design
