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The consumption of bovine milk and its derivatives is associated with inflammation, gastrointestinal disorders and the development of diseases in humans. Most studies related to milk effects are based on either clinal trials or experimental models such as mice and cell cultures. In this study we present the nematode Caenorhabditis elegans as an alternative model to evaluate the effects of milk on oxidative stress in other animal models. The toxicological effect of 20% milk exposure for 8 h on C. elegans was evaluated by progeny quantification, body size and pharyngeal pumping rate. Treating the worms with milk did not affect the worms brood size but interfered with their fecundity by delaying the average number of eggs in the first day of oviposition when compared to the control group. The size of worms treated with milk were significantly smaller compared to control. The pharyngeal pumping rate of milk-treated animals was not significantly different compared to untreated animals. Taking together, the results suggest that 20% milk treatment is not toxic for the worms but induces a minor delay achieving its adulthood and therefore its reproduction period. Milk exposure did not reduce the worms' survival under stress conditions and increase endogenous ROS levels. This study contributes to characterize the effects of milk exposure on the C. elegans nematode., (© 2024. The Author(s).)

The Bromeliaceae family has been used as a model to study adaptive radiation due to its terrestrial, epilithic, and epiphytic habits with wide morpho-physiological variation. Functional groups described by Pittendrigh in 1948 have been an integral part of ecophysiological studies. In the current study, we revisited the functional groups of epiphytic bromeliads using a 204 species trait database sampled throughout the Americas. Our objective was to define epiphytic functional groups within bromeliads based on unsupervised classification, including species from the dry to the wet end of the Neotropics. We performed a hierarchical cluster analysis with 16 functional traits and a discriminant analysis, to test for the separation between these groups. Herbarium records were used to map species distributions and to analyze the climate and ecosystems inhabited. The clustering supported five groups, C 3 tank and CAM tank bromeliads with deep tanks, while the atmospheric group (according to Pittendrigh) was divided into nebulophytes , bromeliads with shallow tanks , and bromeliads with pseudobulbs . The two former groups showed distinct traits related to resource (water) acquisition, such as fog (nebulophytes) and dew (shallow tanks). We discuss how the functional traits relate to the ecosystems inhabited and the relevance of acknowledging the new functional groups.

Citrus sinensis orange juice is an excellent dietary source of β-carotene, a well-known antioxidant. However, β-carotene concentrations are relatively low in most cultivars. We developed a new orange through metabolic engineering strategy (GS) with 33.72-fold increase in β-carotene content compared to its conventional counterpart (CV). Using Caenorhabditis elegans , we found that animals treated with GS showed a greater reduction in intracellular reactive oxygen species (ROS) which is associated with a greater resistance to oxidative stress and induction of the expression of antioxidant genes. Moreover, animals treated with GS orange showed a more effective protection against β-amyloid proteotoxicity and greater hypolipidemic effect under high glucose diet compared to animals treated with CV. These data demonstrate that the increased amount of β-carotene in orange actually provides a greater beneficial effect in C. elegans and a valuable proof of principle to support further studies in mammals and humans., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Obesity is a global public health problem that is associated with oxidative stress. One of the strategies for the treatment of obesity is the use of drugs; however, these are expensive and have numerous side effects. Therefore, the search for new alternatives is necessary. Baccharis trimera is used in Brazilian folk medicine for the treatment of obesity. Here, B. trimera leaf extract (BT) showed antioxidant activity in seven in vitro tests, and it was not toxic to 3T3 murine fibroblasts or Caenorhabditis elegans . Furthermore, BT reduces the intracellular amount of reactive oxygen species and increases C. elegans survival. Moreover, these effects were not dependent on transcription factors. The inhibition of fat accumulation by BT in the C. elegans model was also investigated. BT reduced lipid accumulation in animals fed diets without or with high amount of glucose. Furthermore, it was observed using RNA interference (iRNA) that BT depends on the transcription factor NHR-49 to exert its effect. Phytochemical analysis of BT revealed rutin, hyperoside, and 5-caffeoylquinic acid as the main BT components. Thus, these data demonstrate that BT has antioxidant and anti-obesity effects. However, further studies should be conducted to understand the mechanisms involved in its action.

Alzheimer's disease (AD) is a multifactorial health problem widespread over the world. Regarding the historical importance of the alkaloids in the central nervous system pharmacology they remain as promising drug candidates against AD. Seven alkaloids from Amaryllidaceae and Fabaceae were evaluated in vivo , in vitro and in silico targets related to the AD pathophysiology. Erythraline and erysodine showed the greatest potential compared to Memantine, a drug currently used in AD therapy, by delaying the Aβ 1-42 -induced paralysis in the transgenic strain CL2006 Caenorhabditis elegans , an alternative model to assess the impairment of beta-amyloid peptide deposition. The in vitro inhibition of the acetylcholinesterase was observed for the first time for Erythrina alkaloids; however Lycorine was the most active. Docking simulation contributed to comprehend this potential by showing a hydrophobic interaction between acetylcholinesterase and Lycorine in the amino acid residue TRP 84 as well as hydrogen bonds with TRY 121 and ASP 72.

The genus Coccoloba is widely used in traditional folk medicine, but few scientific data exist for this genus. The goal of this study was to characterise the chemical composition and antioxidant activities of C. alnifolia leaf extracts using in vitro and in vivo assays. Six extracts were obtained: hexane (HE), chloroform (CE), ethanol (EE), methanol (ME), water end extract (WEE), and water extract (WE). Thin-layer chromatography (TLC) analysis showed the presence of phenols, saponins, terpenes, and flavonoids. In vitro assays demonstrated substantial antioxidant potential, especially for polar extracts (EE, ME, WEE, and WE). Moreover, no toxic effects were observed on mammalian cell lines for most of the extracts at the concentrations evaluated. The nematode Caenorhabditis elegans was also used as an in vivo model for testing antioxidant potential. The EE and WE were chosen, based on previously obtained results. It was observed that neither the EE nor the WE had any toxic effect on C. elegans development. Additionally, the antioxidant potential was evaluated using tert -butyl hydroperoxide as a stressor agent. The EE increased the life span of C. elegans by 28% compared to that of the control, and the WE increased the range to 39.2-41.3%. High-performance liquid chromatography (HPLC-DAD) showed the presence of gallic acid, p -coumaric acid, and vitexin in the WE. Therefore, in vitro and in vivo data demonstrated the antioxidant potential of C. alnifolia extracts and their possible biotechnological applications., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2020 Luciana Fentanes Moura de Melo et al.)

Xeroderma pigmentosum complementation group A (XPA), is defective in xeroderma pigmentosum patients, causing pre-disposition to skin cancer and neurological abnormalities, which is not well understood. Here, we analyzed the XPA-deficient cells transcriptional profile under oxidative stress. The imbalance in of ubiquitin-proteasome system (UPS) gene expression was observed in XPA-deficient cells and the involvement of nuclear factor erythroid 2-related factor-2 (NFE2L2) was indicated. Co-immunoprecipitation assays showed the interaction between XPA, apurinic-apyrimidinic endonuclease 1 (APE1) and NFE2L2 proteins. Decreased NFE2L2 protein expression and proteasome activity was also observed in XPA-deficient cells. The data suggest the involvement of the growth arrest and DNA-damage-inducible beta (GADD45β) in NFE2L2 functions. Similar results were obtained in xpa-1 (RNAi) Caenorhabditis elegans suggesting the conservation of XPA and NFE2L2 interactions. In conclusion, stress response activation occurs in XPA-deficient cells under oxidative stress; however, these cells fail to activate the UPS cytoprotective response, which may contribute to XPA patient's phenotypes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

'Cara Cara' is a red orange ( Citrus sinensis (L.) Osbeck) variety originally from Venezuela characterized by a significantly higher and diversified carotenoid content including higher-concentration lycopene, all -E- β -carotene, phytoene, and other carotenoids when compared with the carotenoid profile of its isogenic blond counterpart 'Bahia', also known as Washington navel. The exceptionally high carotenoid content of 'Cara Cara' is of special interest due to its neuroprotective potential. Here, we used the nematode Caenorhabditis elegans to analyze the antioxidant effect and the protection against β -amyloid-induced toxicity of pasteurized orange juice (POJ) obtained from 'Cara Cara' and compare to that from 'Bahia'. POJ treatment reduced the endogenous ROS levels and increased the worm's survival rate under normal and oxidative stress conditions. POJ treatment also upregulated the expression of antioxidant ( gcs-1 , gst-4 , and sod-3 ) and chaperonin ( hsp-16.2 ) genes. Remarkably, ROS reduction, gene expression activation, oxidative stress resistance, and longevity extension were significantly increased in the animals treated with 'Cara Cara' orange juice compared to animals treated with 'Bahia' orange juice. Furthermore, the body paralysis induced by β -amyloid peptide was delayed by both POJs but the mean paralysis time for the worms treated with 'Cara Cara' orange juice was significantly higher compared to 'Bahia' orange juice. Our mechanistic studies indicated that POJ-reduced ROS levels are primarily a result of the direct scavenging action of natural compounds available in the orange juice. Moreover, POJ-induced gst-4::GFP expression and -increased stress resistance was dependent of the SKN-1/Nrf2 transcription factor. Finally, the transcription factors SKN-1, DAF-16, and HSF-1 were required for the POJ-mediated protective effect against A β toxicity. Collectively, these results suggest that orange juice from 'Cara Cara' induced a stronger response against oxidative stress and β -amyloid toxicity compared to orange juice from 'Bahia' possibly due to its higher carotenoid content.

Guarana ( Paullinia cupana ) is largely consumed in Brazil in high energy drinks and dietary supplements because of its stimulant activity on the central nervous system. Although previous studies have indicated that guarana has some protective effects in Parkinson's (PD), Alzheimer's (AD), and Huntington's (HD) disease models, the underlying mechanisms are unknown. Here, we investigated the protective effects of guarana hydroalcoholic extract (GHE) in Caenorhabditis elegans models of HD and AD. GHE reduced polyglutamine (polyQ) protein aggregation in the muscle and also reduced polyQ-mediated neuronal death in ASH sensory neurons and delayed β -amyloid-induced paralysis in a caffeine-independent manner. Moreover, GHE's protective effects were not mediated by caloric restriction, antimicrobial effects, or development and reproduction impairment. Inactivation of the transcription factors SKN-1 and DAF-16 by RNAi partially blocked the protective effects of GHE treatment in the AD model. We show that the protective effect of GHE is associated with antioxidant activity and modulation of proteostasis, since it increased the lifespan and proteasome activity, reduced intracellular ROS and the accumulation of autophagosomes, and increased the expression of SOD-3 and HSP-16.2. Our findings suggest that GHE has therapeutic potential in combating age-related diseases associated with protein misfolding and accumulation.

Diabetes mellitus is associated with altered iron homeostasis that can potentially effect reactive oxygen species generation and contribute to diabetes-related complications. We investigated, by quantitative polymerase chain reaction, whether the expression of liver hepcidin, ferritin, and TfR-1 is altered in diabetes. Rats in the control (C) group received a standard diet; control iron (CI) group received a standard diet supplemented with iron; diabetic (D) group received an injection of streptozotocin; and diabetic iron (DI) group received streptozotocin and the diet with iron. Animals of the D group showed higher levels of serum iron, increased concentration of carbonyl protein, and a decrease in antioxidant status. Group D rats showed increased hepatic expression of Trf-1 compared to the other groups. Iron supplementation reversed this increase. Hepcidin mRNA was 81% higher in DI than in C and CI rats. The results suggest that diabetes, with or without excess iron, can cause perturbations in iron status, hepcidin and Trf-1 expression., (Copyright © 2012 Wiley Periodicals, Inc.)