Using Low-cost Dyes to Visualize Glycogen Accumulation and Gut Integrity in Caenorhabditis elegans.

Caenorhabditis elegans (C. elegans) is a transparent, non-parasitic nematode with a simple biology, which makes it a great tool for biological sciences teaching through the staining of the cells or their molecular content. Lugol dye (iodine-potassium iodide solution) has been widely used in biochemistry to stain glycogen stores. In this context, it is possible to observe differences between fed and starved animals, besides the effects of different conditions, such as different diets and oxygen levels. Erioglaucine is a blue dye that indicates the loss of the intestinal barrier. When the intestinal barrier is intact, the blue dye stains inside the lumen; however, when this integrity is disrupted, the dye leaks into the body cavity. Using a stereomicroscope or a microscope, teachers can demonstrate physiological and biochemical alterations, or they can instigate students to ask a scientific question and hypothesize and test their hypothesis using these assays. The present protocol describes two staining techniques in C. elegans that can be easily carried out by students.

Iron oxide/silver hybrid nanoparticles impair the cholinergic system and cause reprotoxicity in Caenorhabditis elegans.

Iron oxide nanoparticles present superparamagnetic properties that enable their application in various areas, including drug delivery at specific locations in the organism. Silver nanoparticles have potent antimicrobial effects. Although the combination of Fe3O4-NPs and Ag-NPs in one hybrid nanostructure (Fe3O4@Ag-NPs) demonstrated promising targeted biomedical applications, their toxicological effects are unknown and need to be assessed. Caenorhabditis elegans is a promising model for nanotoxicological analysis, as it allows an initial screening of new substances. After exposure to Fe3O4-NPs, Ag-NPs and Fe3O4@Ag-NPs, we observed that hybrid NPs reduced the C. elegans survival and reproduction. Higher concentrations of Fe3O4@Ag-NPs caused an increase in cell apoptosis in the germline and a decrease in egg laying, which was associated with a decrease in worm swimming movements and abnormalities in the cholinergic neurons. Fe3O4@Ag-NPs caused an increase in reactive oxygen species, along with activation of DAF-16 transcription factor. A higher expression of the target genes GST-4::GFP and SOD-3::GFP were evidenced, which suggests the activation of the antioxidant system. Our results indicate the reprotoxicity caused by high levels of Fe3O4@Ag-NPs, as well as cholinergic neurotoxicity and activation of the antioxidant system in C. elegans, suggesting that high concentrations of these nanomaterials can be harmful to living organisms.

LaSOM 335, active against bladder cancer cells, interferes with Let-60 (hRas) and reduces CD73 expression/activity.

Bladder cancer is the fourth most common malignancy in men. It can present along the entire continuum of severity, from mild to well-differentiated disease to extremely malignant tumors with low survival rates. Human RAS genes are the most frequently mutated oncogenes in human cancers, and the critical role of aberrant Ras protein function in carcinogenesis is well established. Therefore, considerable efforts have been devoted to the development of anti-Ras inhibitors for cancer treatment. This study presents the biphenyl dihydropyrimidinone LaSOM 335 with high activity against T24 bladder cancer cells (IC50 = 10.73 ± 0.53 µM) and selectivity of cytotoxicity for this cancer cell line compared to two non-cancer cell lines investigated. Furthermore, we also show that this compound reduced vulvar development in the mutant let-60 gene of Caenorhabditis elegans. Let-60 is a homolog of the mammalian Ras gene. In addition, we observed that LaSOM 335 inhibits the enzymatic activity of CD73 and decreases CD73 expression. Possibly, this expression decrease is due to downstream EGFR signaling via the Ras-Raf-ERK pathway, that directly regulates CD73 expression via ERK1/2. Evidence suggests that non-immunomodulating functions of CD73 play an equally important role for cancer cell survival, progression, and migration. Regarding we also notice that LaSOM 335 was safe in the in vivo model of C. elegans. The set of these findings makes this biphenyl dihydropyrimidinone a promising candidate for further investigations in the bladder cancer field.

Efeito da adição dietética de milho de alta qualidade protéica em camundongos / Effect of adding high-quality protein maize to the diet of mice

OBJETIVO: O objetivo do estudo consistiu em avaliar os efeitos da adição de milho quality protein maize BR473 sobre aspectos bioquímicos e fisiológicos. MÉTODOS: Camundongos Swiss, fêmeas, 6-7 semanas, foram alimentados com rações comerciais, rações comerciais com milho híbrido (1:1), rações comerciais com milho de alta qualidade protéica (1:1). Foram avaliados, durante 3 meses, o consumo de ração, o ganho de peso e de tecido adiposo retroperitoneal e os valores plasmáticos de proteínas, triglicerídeos, colesterol e glicose. RESULTADOS: A adição dietética de milho quality protein maize BR473 reduziu o consumo alimentar e o tecido adiposo retroperitoneal, porém manteve a glicemia e trigliceridemia em relação à adição de milho híbrido na ração comercial. CONCLUSÃO: A melhor eficiência alimentar e os impactos sobre os parâmetros bioquímicos do sangue sugerem o potencial do uso do milho quality protein maize BR473 como um importante complemento para garantir a segurança alimentar e nutricional.

OBJECTIVE: The aim of this work was to evaluate the biochemical and physiological effects of adding quality protein maize BR473 to the diet of mice. METHODS:Female Swiss mice, 6-7 weeks old, were fed commercial diet alone or supplemented with either hybrid maize (1:1) or quality protein maize (1:1). Food intake, weight gain, abdominal obesity and plasma glucose, proteins, cholesterol and triglycerides levels were evaluated for 3 months. RESULTS: Dietary addition of the quality protein maize BR473 reduced food intake and abdominal fat, yet plasma glucose and triglycerides remained the same when compared with the addition of hybrid maize to the commercial feed. CONCLUSION: A better dietary efficiency and the impacts on the biochemical parameters of the blood suggest that the quality protein maize BR473 is an important complement to guarantee dietary and nutritional security.

Modulação da inflamação por ômega-3/6 / Modulation of the inflammation caused by Omega -3/6

Vários estudos vêm demonstrando os efeitos benéficos dos ácidos graxos poliinsaturados, especialmente do tipo ômega-3, no processo inflamatório. Esses lipídios, por meio de interferências na regulação gênica e no metabolismo celular, desempenham um papel modulador das reações in amatórias agudas ou crônicas. Neste trabalho, utilizou-se o modelo inflamatório induzido por implantes subcutâneos de parafina afim de avaliar os efeitos da administração dos ácidos graxos poliinsaturados por via oral e subcutânea. Foram utilizados camundongos Swiss, fêmeas, com 6 a 8 semanas de idade. Posteriormente, os animais receberam um implante subcutâneo de tabletes de parafina afim de induzir um processo inflamatório crônico. Vinte e um dias após a indução da inflamação, os animais receberam 100μl/camundongo de óleo de peixe contendo 180mg de ácido eicosapentaenóico e 120mg de ácido docosahexaenóico via oral. Pela via subcutânea, foram inoculados 20μl/camundongo de óleo de peixe contendo 3,6mg de ácido eicosapentaenóico e 2,4mg de ácido docosahexaenóico. Os camundongos receberam 8 (1 vez/semana) ou 24 (3 vezes/semana) inoculações, dependendo do experimento. O grupo controle (n = 5) recebeu tratamento com salina...

Several studies show that omega-3 polyunsaturated fatty acids suppress the immune response and inflammation. Some of the effects of omega-3 are brought about by modulation of the amount and types of eicosanoids made, and other effects are elicited by eicosanoid-in dependent mechanisms, including actions up on intracellular signaling pathways, transcription factor activity and gene expression. The aim of this study was to evaluate the effect of oral or subcutaneous omega-3 administration in chronic pathological conditions advancing.To determine whether chronic inflammation induced by paraffin implants is altered by w-3 supplementation, six to eight-week-old male Swiss (n = 5)...