Oxidative stress promotes cytotoxicity in human cancer cell lines exposed to Escallonia spp. extracts.

BACKGROUND: Standard cancer treatments show a lack of selectivity that has led to the search for new strategies against cancer. The selective elimination of cancer cells modulating the redox environment, known as "selective oxycution", has emerged as a viable alternative. This research focuses on characterizing the unexplored Escallonia genus plant extracts and evaluating their potential effects on cancer's redox balance, cytotoxicity, and activation of death pathways. METHODS: 36 plant extracts were obtained from 4 different species of the Escallonia genus (E. illinita C. Presl, E. rubra (Ruiz & Pav.) Pers., E. revoluta (Ruiz & Pav.) Pers., and E. pulverulenta (Ruiz & Pav.) Pers.), which were posteriorly analyzed by their phytoconstituents, antioxidant capacity, and GC-MS. Further, redox balance assays (antioxidant enzymes, oxidative damage, and transcription factors) and cytotoxic effects (SRB, ∆Ψmt, and caspases actives) of those plant extracts were analyzed on four cell lines (HEK-293T, MCF-7, HT-29, and PC-3). RESULTS: 36 plant extracts were obtained, and their phytoconstituents and antioxidant capacity were established. Further, only six extracts had EC50 values < 10 µg*mL- 1, indicating high toxicity against the tested cells. From those, two plant extracts were selective against different cancer cell lines: the hexane extract of E. pulverulenta´s stem was selective for HT-29, and the ethyl acetate extract of E. rubra´s stem was selective for PC-3. Both extracts showed unbalanced redox effects and promoted selective cell death. CONCLUSIONS: This is the first study proving "selective oxycution" induced by Chilean native plant extracts.

Ghrelin-responsive mediobasal hypothalamic neurons mediate exercise-associated food intake and exercise endurance.

Previous studies have implicated the orexigenic hormone ghrelin as a mediator of exercise endurance and the feeding response postexercise. Specifically, plasma ghrelin levels nearly double in mice when they are subjected to an hour-long bout of high-intensity interval exercise (HIIE) using treadmills. Also, growth hormone secretagogue receptor-null (GHSR-null) mice exhibit decreased food intake following HIIE and diminished running distance (time until exhaustion) during a longer, stepwise exercise endurance protocol. To investigate whether ghrelin-responsive mediobasal hypothalamus (MBH) neurons mediate these effects, we stereotaxically delivered the inhibitory designer receptor exclusively activated by designer drugs virus AAV2-hSyn-DIO-hM4(Gi)-mCherry to the MBH of Ghsr-IRES-Cre mice, which express Cre recombinase directed by the Ghsr promoter. We found that chemogenetic inhibition of GHSR-expressing MBH neurons (upon delivery of clozapine-N-oxide) 1) suppressed food intake following HIIE, 2) reduced maximum running distance and raised blood glucose and blood lactate levels during an exercise endurance protocol, 3) reduced food intake following ghrelin administration, and 4) did not affect glucose tolerance. Further, HIIE increased MBH Ghsr expression. These results indicate that activation of ghrelin-responsive MBH neurons is required for the normal feeding response to HIIE and the usual amount of running exhibited during an exercise endurance protocol.

Selenium Nanoparticles Biosynthesized by Pantoea agglomerans and Their Effects on Cellular and Physiological Parameters in the Rainbow Trout Oncorhynchus mykiss.

The applications of nanoparticles (Nps) as food additives, health enhancers, and antimicrobials in animal production are increasing. The aim of this study was to evaluate the effect of selenium (Se) nanoparticles (Se0Nps) stabilized with L-cysteine (Se0Nps/L-Cys), as a nutritional supplement, on immunological, oxidative status, and productive parameters in O. mykiss. TEM and SEM-EDS showed the accumulation of spherical Se0Nps entirely composed by elemental selenium (Se0) as intracellular and extracellular deposits in Pantoea agglomerans UC-32 strain. The in vitro antioxidant capacity of Se0Nps/L-Cys was significant more efficient ROS scavengers than Se0Nps and Na2SeO3. We also evaluate the effect of Se0Nps/L-Cys on cell viability and oxidative stress in RTgill-W1, RTS-11, or T-PHKM Oncorhynchus mykiss cell lines. Se0Nps/L-Cys showed less toxic and high antioxidant activity than Se0Nps and Na2SeO3. Finally, the dietary Se0Nps/L-Cys had a significant better effect on both plasma lysozyme and respiratory burst activity (innate immune response), on tissular Gpx activity (oxidative status), and on well-being (productive parameter) of O. mykiss when it is compared to Se0Nps and Na2SeO3. Se0Nps/L-Cys is a promising alternative for nutritional supplement for O. mykiss with better performance than Na2SeO3 and Se0Nps, ease to implementation, and reduced environmental impact.

Tea Bags for Fmoc Solid-Phase Peptide Synthesis: An Example of Circular Economy.

Peptide synthesis is an area with a wide field of application, from biomedicine to nanotechnology, that offers the option of simultaneously synthesizing a large number of sequences for the purpose of preliminary screening, which is a powerful tool. Nevertheless, standard protocols generate large volumes of solvent waste. Here, we present a protocol for the multiple Fmoc solid-phase peptide synthesis in tea bags, where reagent recycling steps are included. Fifty-two peptides with wide amino acid composition and seven to twenty amino acid residues in length were synthesized in less than three weeks. A clustering analysis was performed, grouping the peptides by physicochemical features. Although a relationship between the overall yield and the physicochemical features of the sequences was not established, the process showed good performance despite sequence diversity. The recycling system allowed to reduce N, N-dimethylformamide usage by 25-30% and reduce the deprotection reagent usage by 50%. This protocol has been optimized for the simultaneous synthesis of a large number of peptide sequences. Additionally, a reagent recycling system was included in the procedure, which turns the process into a framework of circular economy, without affecting the quality of the products obtained.

The Circadian System: A Regulatory Feedback Network of Periphery and Brain.

Circadian rhythms are generated by the autonomous circadian clock, the suprachiasmatic nucleus (SCN), and clock genes that are present in all tissues. The SCN times these peripheral clocks, as well as behavioral and physiological processes. Recent studies show that frequent violations of conditions set by our biological clock, such as shift work, jet lag, sleep deprivation, or simply eating at the wrong time of the day, may have deleterious effects on health. This infringement, also known as circadian desynchronization, is associated with chronic diseases like diabetes, hypertension, cancer, and psychiatric disorders. In this review, we will evaluate evidence that these diseases stem from the need of the SCN for peripheral feedback to fine-tune its output and adjust physiological processes to the requirements of the moment. This feedback can vary from neuronal or hormonal signals from the liver to changes in blood pressure. Desynchronization renders the circadian network dysfunctional, resulting in a breakdown of many functions driven by the SCN, disrupting core clock rhythms in the periphery and disorganizing cellular processes that are normally driven by the synchrony between behavior and peripheral signals with neuronal and humoral output of the hypothalamus. Consequently, we propose that the loss of synchrony between the different elements of this circadian network as may occur during shiftwork and jet lag is the reason for the occurrence of health problems.

Enjuagues de Calendula officinalis como alternativa de los antisépticos orales / Calendula officinalis mouthrinses as an alternative to oral antiseptics

En la progresión de la enfermedad periodontal intervienen múltiples factores, incluyendo los diversos microorganismos orales que conforman la placa bacteriana o patógenos libres en cavidad oral que logran desencadenar una respuesta inmunológica e inflamatoria en el huésped. Existen herramientas químicas que combaten cualquier posibilidad de colonización e infección por parte de algún microorganismo. Los antisépticos orales son de gran utilidad especialmente luego de cirugías periodontales. Es allí donde su importancia se hace casi imprescindible, para controlar la noxa, pero a su vez deben facilitar el proceso de cicatrización de los tejidos involucrados. El objetivo del presente manuscrito consistió en reportar y describir un caso clínico donde el empleo de clorhexidina al 0,12 por ciento como antiséptico oral postoperatorio no favoreció la cicatrización adecuada de los tejidos mucosos luego de realizarse un injerto gingival libre. Como alternativa antiséptica se prescribieron enjuagues a base de Caléndula, observándose cicatrización de los tejidos afectados a los pocos días de uso. Se discute que posterior a todo proceso operatorio de carácter quirúrgico se debe colocar en una balanza riesgo-beneficio, donde se escoge la posibilidad de evitar la infección posoperatoria o la cicatrización oportuna de esta. Los enjuagues orales de caléndula permitieron la cicatrización oportuna; los colutorios de caléndula contemplan una pequeña proporción de capacidad antimicrobiana y una alta habilidad inductora de la cicatrización tisular(AU)

Periodontal disease progression involves multiple factors, including several oral microorganisms of the bacterial biofilm or commensal pathogens in oral cavity, which trigger inflammatory immune response in the host. There are chemical tools that fight any possibility of colonization and infection by a microorganism. Oral antiseptics are useful especially after periodontal surgery where they are almost indispensable to control the noxa, but at in the same time, they should facilitate the healing process of the cut tissues. The objective of this paper was to describe a case in which the use of 0.12 percent chlorhexidine as an oral antiseptic postoperatively favored no proper healing of mucosal tissues after free gingival grafting. As an alternative, mouthrinse with Calendula was prescribed, observing affected tissue healing within a few days. It is argued that in all post-operative surgical process, one should analyze risks and benefits and choose avoiding the possibility of postoperative infection or timely scarring. As an alternative, the calendula mouthrinse allowed timely cicatrization and it should be noticed that they have some antimicrobial properties and high-inductive ability for the tissue healing(AU)