Curcumin promotes apoptosis of human melanoma cells by caspase 3

Cutaneous melanoma (CM) is a malignant neoplasm with a high metastatic rate that shows poor response to systemic treatments in patients with advanced stages. Recently, studies have highlighted the antineoplastic potential of natural compounds, such as polyphenols, in the adjuvant therapy context to treat CM. The objective of the present study was to evaluate the effect of different concentrations of curcumin (0.1-100 µM) on the metastatic CM cell line SK-MEL-28. The cells were treated for 6 and 24 h with different concentrations of curcumin. Cell viability was assessed by 3-(4,5-dimethyl-2thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and fluorescence microscopy. The apoptotic-inducing potential was detected by annexin V flow cytometry. The wound healing assay was used to verify cell migration after the curcumin exposition. The redox profile was evaluated by levels of the pro-oxidant markers reactive oxygen species (ROS) and Nitric oxide (NOx) and antioxidants of total thiols (PSH) and nonprotein thiols. The gene expression and enzymatic activity of caspase 3 were evaluated by reverse transcription-quantitative polymerase chain reaction and a sensitive fluorescence assay, respectively. Curcumin significantly decreased the cell viability of SK-MEL-28 cells at both exposure times. It also induced apoptosis at the highest concentration tested (p < .0001). SK-MEL-28 cell migration was inhibited by curcumin after treatment with 10 µM (p < .0001) and 100 µM (p < .0001) for 6 and 24 h (p = .0006 and p < .0001, respectively). Furthermore, curcumin significantly increased levels of ROS and NOx. Finally, curcumin was capable of increasing the gene expression at 10 µM (p = .0344) and 100 µM (p = .0067) and enzymatic activity at 10 µM (p = .0086) and 100 µM (p < .0001) of caspase 3 after 24 h. For the first time, we elucidated in our study that curcumin increases ROS levels, promoting oxidative stress that activates the caspase pathway and culminates in SK-MEL-28 metastatic CM cell death.

Resistance training reduces platelet activation in hypertensive women: the role of purinergic signaling

BACKGROUND AND AIM

Essential arterial hypertension is a risk factor for stroke, myocardial infarction, heart failure, and arterial aneurysm, which are related to the activation of platelets. Purinergic signaling has a central role in platelet aggregation. Although ATP and ADP can act as a proaggregant agent, adenosine inhibits platelet aggregation and reduces vascular injury. Physical exercise exhibits antiaggregant properties and can modulate purinergic system. The aim of this study was to evaluate the effect of 6 months of resistance training on purinergic system components in platelets and on platelet activation, hemodynamic and anthropometric parameters in hypertensive woman.

METHOD

A total of 31 hypertensive and 28 normotensive middle-aged sedentary women were submitted to 6 months of resistance training. Purinergic enzymes activities were assessed in platelets; ATP and Tromboxane B2 (TXB2) levels were measured in serum. Blood pressure (BP), BMI, and body fat were also measured. All variables were statistically analyzed, considering P value less than 0.05.

RESULTS

Six months of resistance training was able to significantly reduce BP, ATP, and TXB2 levels as well as NTPDase, ecto-5'nucleotidase, and ADA activities in hypertensive group. After 6 months of resistance training, purinergic system components and TXB2 of hypertensive group were similar to normotensive group in platelets, demonstrating that resistance training was able to modulate platelet activation. A positive correlation was found between BP, enzyme activities, and levels of ATP and TXB2.

CONCLUSION

Our findings demonstrated the relationship between purinergic signaling and platelet activation in hypertension and suggests that resistance training serve as tool to reduce platelet aggregation in hypertensive woman by modulating purinergic system.

Antineoplastic properties of polyphenols in TPC-1 human papillary thyroid carcinoma cell line: a systematic review

Thyroid cancer usually responds to surgical and ablative therapy, but when it's refractory the alternative lies in tyrosine kinase inhibitors that, in addition to harmful side effects, acts only in a palliative way. The concern for other therapeutic possibilities brought evidence on flavonoids, hypothesizing a possible strategy. This review aimed to organize a compilation of in vitro studies using polyphenol substances in TPC-1 (human papillary thyroid carcinoma cell line) summarizing it's results and describing the metabolic pathways involved. Articles were selected on PubMed, Google Scholar, LILACS, BVS and SciELO, using keywords "thyroid cancer", "flavonoids" and "TPC-1", until June 2022. 185 studies were selected. After identification and exclusion of duplicates and exclusion criteria applied, 11 original articles were evaluated. Of these, the findings of flavonoids added to TPC-1 were: inhibition of cell growth and viability, promotion of cell cycle arrest and induction of apoptosis. Polyphenolic compounds have antineoplastic properties by different mechanisms as shown in vitro, but the concentrations needed are above usual dietary consumption and the findings are limited to experimental cellular studies. Despite that, these results should be useful to guide further analysis aiming to reveal the real safety and efficacy of polyphenols in this scenario.

Pancreatic Insufficiency in a Child with p.Gly542* and c.2657+5G>A Heterozygote CFTR: A Case Report

Cystic fibrosis is a monogenic and autosomal recessive disease. It is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator gene responsible for encoding the CFTR protein. Involvement of the gastrointestinal and respiratory systems is the main clinical manifestation. In this case, we report a heterozygous CFTR patient harboring class I (p.Gly542*) and class V (c.2657+5G>A) mutations. The importance of this case report lies in the clinical features because the patient, aged 3 years, presented with early exocrine pancreatic insufficiency, which can be considered atypical, as most individuals with this genotype are pancreatic sufficient or develop pancreatic insufficiency later in life. This report aims at presenting the tests requested that contributed to the patient's diagnosis, as well as at understanding the association between these mutations and their phenotypic presentation. Interpretation of the genotype-phenotype relationship represents a challenge, as genetic analysis alone is not sufficient to clearly predict severity of the disease. This is because the significant phenotypic heterogeneity existing among patients with the same genotype may exert socioeconomic and sociocultural influences, or by the action of CFTR modifiers, such as environmental and modifying genes, which can alter the protein's function and exert an impact on the individual's phenotype.

Purinergic signaling as a new mechanism underlying physical exercise benefits: a narrative review

In the last years, it has become evident that both acute and chronic physical exercise trigger responses/adaptations in the purinergic signaling and these adaptations can be considered one important mechanism related to the exercise benefits for health improvement. Purinergic system is composed of enzymes (ectonucleotidases), receptors (P1 and P2 families), and molecules (ATP, ADP, adenosine) that are able to activate these receptors. These components are widely distributed in almost all cell types, and they respond/act in a specific manner depending on the exercise types and/or intensities as well as the cell type (organ/tissue analyzed). For example, while acute intense exercise can be associated with tissue damage, inflammation, and platelet aggregation, chronic exercise exerts anti-inflammatory and anti-aggregant effects, promoting health and/or treating diseases. All of these effects are dependent on the purinergic signaling. Thus, this review was designed to cover the aspects related to the relationship between physical exercise and purinergic signaling, with emphasis on the modulation of ectonucleotidases and receptors. Here, we discuss the impact of different exercise protocols as well as the differences between acute and chronic effects of exercise on the extracellular signaling exerted by purinergic system components. We also reinforce the concept that purinergic signaling must be understood/considered as a mechanism by which exercise exerts its effects.

Role of inflammation and oxidative stress in tissue damage associated with cystic fibrosis: CAPE as a future therapeutic strategy

Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, responsible for the synthesis of the CFTR protein, a chloride channel. The gene has approximately 2000 known mutations and all of them affect in some degree the protein function, which makes the pathophysiological manifestations to be multisystemic, mainly affecting the respiratory, gastrointestinal, endocrine, and reproductive tracts. Currently, the treatment of the disease is restricted to controlling symptoms and, more recently, a group of drugs that act directly on the defective protein, known as CFTR modulators, was developed. However, their high cost and difficult access mean that their use is still very restricted. It is important to search for safe and low-cost alternative therapies for CF and, in this context, natural compounds and, mainly, caffeic acid phenethyl ester (CAPE) appear as promising strategies to assist in the treatment of the disease. CAPE is a compound derived from propolis extracts that has antioxidant and anti-inflammatory activities, covering important aspects of the pathophysiology of CF, which points to the possible benefit of its use in the disease treatment. To date, no studies have effectively tested CAPE for CF and, therefore, we intend with this review to elucidate the role of inflammation and oxidative stress for tissue damage seen in CF, associating them with CAPE actions and its pharmacologically active derivatives. In this way, we offer a theoretical basis for conducting preclinical and clinical studies relating the use of this molecule to CF.