Endothelial Biomarkers in Critically Ill COVID-19 Patients: Potential Predictors of the Need for Dialysis.

INTRODUCTION: The aim of this was to evaluate the function of vascular biomarkers to predict the need for hemodialysis in critically ill patients with COVID-19. METHODS: This is a prospective study with 58 critically ill patients due to COVID-19 infection. Laboratory tests in general and vascular biomarkers, such as VCAM-1, syndecan-1, angiopoietin-1, and angiopoietin-2, were quantified on intensive care unit (ICU) admission. RESULTS: There was a 40% death rate. VCAM and Ang-2/Ang-1 ratio on ICU admission were associated with the need for hemodialysis. Vascular biomarkers (VCAM-1, syndecan-1, angiopoietin-2/angiopoietin-1 ratio) were predictors of death and their cutoff values were useful to stratify patients with a worse prognosis. In the multivariate cox regression analysis with adjusted models, VCAM-1 (OR 1.13 [CI 95%: 1.01-1.27]; p = 0.034) and Ang-2/Ang-1 ratio (OR 4.87 [CI 95%: 1.732-13.719]; p = 0.003) were associated with the need for dialysis. CONCLUSION: Vascular biomarkers, mostly VCAM-1 and Ang-2/Ang-1 ratio, showed better efficiency to predict the need for hemodialysis in critically ill COVID-19 patients.

1α,25-Dihydroxyvitamin D3 (VD3) Shows a Neuroprotective Action Against Rotenone Toxicity on PC12 Cells: An In Vitro Model of Parkinson's Disease.

Parkinson's disease (PD) is characterized by dopaminergic cell loss in the substantia nigra, and PD brains show neuroinflammation, oxidative stress, and mitochondrial dysfunction. The study evaluated the neuroprotective activity of 1α,25-dihydroxy vitamin D3 (VD3), on the rotenone (ROT)-induced cytotoxicity in PC12 cells. The viability parameters were assessed by the MTT and flow cytometry, on cells treated or not with VD3 and/or ROT. Besides, ROS production, cell death, mitochondrial transmembrane potential, reduced GSH, superoxide accumulation, molecular docking (TH and Keap1-Nrf2), and TH, Nrf2, NF-kB, and VD3 receptor protein contents by western blot were evaluated. VD3 was shown to improve the viability of ROT-exposed cells. Cells exposed to ROT showed increased production of ROS and superoxide, which decreased after VD3. ROT decrease in the mitochondrial transmembrane potential was prevented, after VD3 treatment and, VD3 was shown to interact with tyrosine hydroxylase (TH) and Nrf2. While ROT decreased TH, Nrf2, and NF-kB expressions, these effects were reversed by VD3. In addition, VD3 also increased VD3 receptor protein contents and values went back to those of controls after ROT exposure. VD3 protects PC12 cells against ROT damage, by decreasing oxidative stress and improving mitochondrial function. One target seems to be the TH molecule and possibly an indirect Nrf2 activation could also justify its neuroprotective actions on this PC12 cell model of PD.

Trypanocidal potential of synthetic p-aminochalcones: In silico and in vitro evaluation.

Chagas disease (CD) is a neglected tropical disease of worldwide health concern, caused by the flagellate protozoan Trypanosoma cruzi (T. cruzi), endemic in Latin America and present in North America and Europe. The WHO recommended drug for CD, benznidazole has low safety profile and several limitations. Therefore, an entity with better therapeutic potential to treat CD is required. Chalcones are an important class of compounds, which have shown antichagasic potential. Thus, the objective of this study was to evaluate the activity of synthetic p-aminochalcones against T. cruzi. Chalcones 1 and 2 were synthesized by Claisen-Schmidt condensation and characterized by both spectroscopic and theoretical methods. Initially, they were submitted to molecular docking simulations using cruzain and trypanothione reductase (TR) enzymes. It was expected to observe the possible interactions of chalcones with the catalytic site and other important regions of these main pharmacological targets of T. cruzi. Their cytotoxicity within host cells were assessed by MTT reduction assay using LLC-MK2 cells, with CC50 = 85.6 ± 9.2 µM and 1115 ± 381.7 µM for chalcones 1 and 2, respectively. These molecules were also tested against epimastigote and trypomastigote life forms of T. cruzi, causing reduction in the number of viable parasites. For the evaluation of the effect on intracellular amastigotes, infected LLC-MK2 cells were incubated with the chalcones for 24 h, causing reduction in the percentage of infected cells and the number of amastigotes/100 cells. Finally, flow cytometry assays were performed for analyzing cell death mechanisms (7-AAD/AxPE labelling), cytoplasmic ROS accumulation (DCFH-DA assay) and mitochondrial transmembrane potential disruption (Rho123 assay). Both chalcones (1 and 2) caused membrane damage, ROS accumulation and mitochondrial depolarization. In conclusion, the synthetic p-aminochalcones presented trypanocidal effect, causing membrane damage and oxidative stress. Their mechanism of action may be related to cruzain and TR inhibition.

Marine-Derived Components: Can They Be a Potential Therapeutic Approach to Parkinson's Disease?

The increase in the life expectancy average has led to a growing elderly population, thus leading to a prevalence of neurodegenerative disorders, such as Parkinson's disease (PD). PD is the second most common neurodegenerative disorder and is characterized by a progressive degeneration of the dopaminergic neurons in the substantia nigra pars compacta (SNpc). The marine environment has proven to be a source of unique and diverse chemical structures with great therapeutic potential to be used in the treatment of several pathologies, including neurodegenerative impairments. This review is focused on compounds isolated from marine organisms with neuroprotective activities on in vitro and in vivo models based on their chemical structures, taxonomy, neuroprotective effects, and their possible mechanism of action in PD. About 60 compounds isolated from marine bacteria, fungi, mollusk, sea cucumber, seaweed, soft coral, sponge, and starfish with neuroprotective potential on PD therapy are reported. Peptides, alkaloids, quinones, terpenes, polysaccharides, polyphenols, lipids, pigments, and mycotoxins were isolated from those marine organisms. They can act in several PD hallmarks, reducing oxidative stress, preventing mitochondrial dysfunction, α-synuclein aggregation, and blocking inflammatory pathways through the inhibition translocation of NF-kB factor, reduction of human tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6). This review gathers the marine natural products that have shown pharmacological activities acting on targets belonging to different intracellular signaling pathways related to PD development, which should be considered for future pre-clinical studies.

Piplartine-Inspired 3,4,5-Trimethoxycinnamates: Trypanocidal, Mechanism of Action, and In Silico Evaluation.

Chagas disease (CD) is one of the main neglected tropical diseases that promote relevant socioeconomic impacts in several countries. The therapeutic options for the treatment of CD are limited, and parasite resistance has been reported. Piplartine is a phenylpropanoid imide that has diverse biological activities, including trypanocidal action. Thus, the objective of the present work was to prepare a collection of thirteen esters analogous to piplartine (1-13) and evaluate their trypanocidal activity against Trypanosoma cruzi. Of the tested analogues, compound 11 ((E)-furan-2-ylmethyl 3-(3,4,5-trimethoxyphenyl)acrylate) showed good activity with IC50 values = 28.21 ± 5.34 µM and 47.02 ± 8.70 µM, against the epimastigote and trypomastigote forms, respectively. In addition, it showed a high rate of selectivity to the parasite. The trypanocidal mechanism of action occurs through the induction of oxidative stress and mitochondrial damage. In addition, scanning electron microscopy showed the formation of pores and leakage of cytoplasmic content. Molecular docking indicated that 11 probably produces a trypanocidal effect through a multi-target mechanism, including affinity with proteins CRK1, MPK13, GSK3B, AKR, UCE-1, and UCE-2, which are important for the survival of the parasite. Therefore, the results suggest chemical characteristics that can serve for the development of new trypanocidal prototypes for researching drugs against Chagas disease.

Endothelial biomarkers as predictors for haemodialysis need in severe leptospirosis patients (Weil's disease).

OBJECTIVE: To investigate the prediction ability of vascular injury biomarkers for haemodialysis requirement in patients with severe leptospirosis. METHODS: Prospective study with severe leptospirosis patients hospitalised in Fortaleza, Brazil. Blood samples were collected hospital admission to quantify vascular injury biomarkers: syndecan-1, ICAM-1, VCAM-1, angiopoietin-2 and FGF-23. Two groups were evaluated according to haemodialysis requirement during hospital stay. RESULTS: Twenty-seven patients were included, with a mean age of 39 ± 18 years. 88.9% were males. 53.8% needed haemodialysis and presented higher levels on hospital admission of syndecan-1 (572 [300-811] vs. 263 [106-421] ng/ml; p = 0.03), angiopoietin-2 (1.52 [0.72-2.72] vs. 0.63 [0.4-1.38] ng/ml; p = 0.01), and FGF-23 (291 [56-2031] vs. 10 [10-806] pg/ml; p = 0.021). Syndecan-1 showed significant correlation with creatinine (r = 0.546; p = 0.05) and total bilirubin levels (r = 0.534; p = 0.013) on hospital admission. Angiopoietin-2 showed significant correlation with creatinine levels (r = 0.513; p = 0.009) on hospital admission and with number of haemodialysis sessions (r = 0.406; p = 0.049). No significant correlation was found with FGF-23. Regarding prognostic performance, combined syndecan-1 and angiopoietin-2 levels had a better ability to predict haemodialysis need in patients with severe leptospirosis (AUC-ROC = 0.744 [95% CI: 0.545-0.943] p = 0.035). CONCLUSION: Syndecan-1 and angiopoietin-2 were associated with haemodialysis need in patients with severe leptospirosis and may be useful to improve therapeutic approach and reduce mortality.

Quantum mechanical, molecular docking, molecular dynamics, ADMET and antiproliferative activity on Trypanosoma cruzi (Y strain) of chalcone (E)-1-(2-hydroxy-3,4,6-trimethoxyphenyl)-3-(3-nitrophenyl)prop-2-en-1-one derived from a natural product.

Chagas disease is a leading public health problem. More than 8 million people are affected by the disease, which is endemic in 21 countries in Latin America, generating an average annual cost of 7.2 billion dollars per year. The conventional treatment of Chagas disease is carried out by administering the drug benznidazole (BZN), which has caused numerous adverse reactions. Hence, the search for new, more efficient, and less toxic anti-chagasic agents is essential. Recently, chalcones have been researched to propose new therapies against neglected diseases, mainly Trypanosoma cruzi. The objective of this work was to evaluate for the first time the antiproliferative potential of chalcone derived from the natural product on T. cruzi strain Y. The molecular structure of the chalcone was confirmed by spectrometric data. The toxicity of chalcone in LLC-MK2 cells indicated that a concentration of 514.10 ± 62.40 µM was able to reduce cell viability by 50%. Regarding the effect of chalcone on epimastigote forms, an IC50 value of 46.57 ± 9.81 µM was observed; 45.92 ± 8.42 and 16.32 ± 3.41 µM at times of 24, 48 and 72 hours, respectively. The chalcone was able to eliminate trypomastigote forms at all concentrations tested, except for 31.25 µM, with LC50 values of 117.90 ± 12.60 µM, lower than the reference drug BZN (161.40 ± 31. 80 µM). The mechanism of action may be related to the membrane damage provoked by reduction of the mitochondrial potential. The anti-T. cruzi effect can be assigned through some structural aspects of the chalcone as the nitro group (NO2) is present, which can be enzymatically reduced forming a nitro radical, and the presence of methoxyl groups in the A ring of the chalcone. In silico studies showed that the chalcone had a higher affinity for cruzain when compared to BZN and the co-crystallized inhibitor KB2, as it presented a more thermodynamically stable complex in the order of -6.9 kcal mol-1. The pharmacokinetic prediction showed a significant probability of antiprotozoal activity, a good volume of distribution after being absorbed in the intestine, and a low chance of activity in the central nervous system. Therefore, these results suggest that the chalcone can become a potential cruzain enzyme inhibitor with trypanocidal activity.

Antiparasitary and antiproliferative activities in vitro of a 1,2,4-oxadiazole derivative on Trypanosoma cruzi.

Chagas disease (CD) is a neglected disease, prevalent and endemic in Latin America, but also present in Europe and North America. The main treatment used for this disease is benznidazole, but its efficacy is variable in the chronic phase and presents high toxicity. So, there is a need for the development of new therapeutic agents. The five-membered heterocyclic 1,2,4-oxadiazole ring has received attention for its unique properties and a broad spectrum of biological activities and is therefore a potential candidate for the development of new drugs. Thus, the aim of this study was to evaluate the activity of the N-cyclohexyl-3-(3-methylphenyl)-1,2,4-oxadiazol-5-amine (2) on the evolutionary forms of Trypanosoma cruzi strain Y, as well as its mechanisms of action and in silico theoretical approach. The results by computational method showed an interaction of the 1,2,4-oxadiazole (2) with TcGAPDH, cruzain, and trypanothione reductase, showing good charge distribution and affinity in those three targets. Furthermore, cytotoxicity in LLC-MK2 cells was performed by the MTT method. In the assays with different parasite forms, the tested compound showed similar time-dependent concentration effect. The evaluation of the antiamastigote effect between the two concentrations tested showed a reduction in the number of infected cells and also in the number of amastigotes per infected cell. By flow cytometry, the compound (2) displayed alterations suggestive of necrotic events. Finally, in scanning electron microscopy structural alterations were present, characteristic of necrosisin the epimastigote forms. Overall, the 1,2,4-oxadiazole derivative (2) here evaluated opens perspectives to the development of new antichagasic agents.

Antiulcerogenic Potential of the Ethanolic Extract of Ceiba speciosa (A. St.-Hil.) Ravenna Evaluated by In Vitro and In Vivo Studies.

Gastrointestinal diseases, such as peptic ulcers, are caused by a damage in the gastric mucosa provoked by several factors. This stomach injury is regulated by many inflammatory mediators and is commonly treated with proton-pump inhibitors, histamine H2 receptor blockers and antacids. However, various medicinal plants have demonstrated positive effects on gastric ulcer treatment, including plants of the Ceiba genus. The aim of this study was to evaluate the antiulcer and anti-inflammatory activities of the stem bark ethanolic extract of Ceiba speciosa (A. St.-Hil.) Ravenna. We performed a preliminary quantification of phenolic compounds by high-performance liquid chromatography-diode array detection (HPLC-DAD), followed by the prospection of other chemical groups through nuclear magnetic resonance (NMR) spectroscopy. A set of in vitro assays was used to evaluate the extract potential regarding its antioxidant activity (DPPH: 19.83 ± 0.34 µg/mL; TPC: 307.20 ± 6.20 mg GAE/g of extract), effects on cell viability and on the release of TNF-α in whole human blood. Additionally, in vivo assays were performed to evaluate the leukocyte accumulation and total protein quantification in carrageenan-induced air pouch, as well as the antiulcerogenic effect of the extract on an ethanol-induced ulcer in rats. The extract contains flavonoids and phenolic compounds, as well as sugars and quinic acid derivatives exhibiting potent antioxidant activity and low toxicity. The extract reduced the release of TNF-α in human blood and inhibited the activity of p38α (1.66 µg/mL), JAK3 (5.25 µg/mL), and JNK3 (8.34 µg/mL). Moreover, it reduced the leukocyte recruitment on the pouch exudate and the formation of edema, reverting the effects caused by carrageenan. The extract presented a significant prevention of ulcer formation and a higher reduction than the reference drug, Omeprazole. Therefore, C. speciosa extract has demonstrated relevant therapeutic potential for the treatment of gastric diseases, deserving the continuation of further studies to unveil the mechanisms of action of plant bioactive ingredients.

Saccorhiza polyschides-A Source of Natural Active Ingredients for Greener Skincare Formulations.

The growing knowledge about the harmful effects caused by some synthetic ingredients present in skincare products has led to an extensive search for natural bioactives. Thus, this study aimed to investigate the dermatological potential of five fractions (F1-F5), obtained by a sequential extraction procedure, from the brown seaweed Saccorhiza polyschides. The antioxidant (DPPH, FRAP, ORAC and TPC), anti-enzymatic (collagenase, elastase, hyaluronidase and tyrosinase), antimicrobial (Staphylococcus epidermidis, Cutibacterium acnes and Malassezia furfur), anti-inflammatory (nitric oxide, tumor necrosis factor-α, interleukin-6 and interleukin-10) and photoprotective (reactive oxygen species) properties of all fractions were evaluated. The ethyl acetate fraction (F3) displayed the highest antioxidant and photoprotective capacity, reducing ROS levels in UVA/B-exposed 3T3 fibroblasts, and the highest anti-enzymatic capacity against tyrosinase (IC50 value: 89.1 µg/mL). The solid water-insoluble fraction (F5) revealed the greatest antimicrobial activity against C. acnes growth (IC50 value: 12.4 µg/mL). Furthermore, all fractions demonstrated anti-inflammatory potential, reducing TNF-α and IL-6 levels in RAW 264.7 macrophages induced with lipopolysaccharides. Chemical analysis of the S. polyschides fractions by NMR revealed the presence of different classes of compounds, including lipids, polyphenols and sugars. The results highlight the potential of S. polyschides to be incorporated into new nature-based skincare products.

Disclosing the potential of eleganolone for Parkinson's disease therapeutics: Neuroprotective and anti-inflammatory activities.

The treatment of Parkinson´s disease (PD) has benefited from significant advances resulting from the increasing research efforts focused on new therapeutics. However, the current treatments for PD are mostly symptomatic, alleviating disease symptoms without reversing or retarding disease progression. Thus, it is critical to find new molecules that can result in more effective treatments. Within this framework, this study aims to evaluate the neuroprotective and anti-inflammatory effects of three compounds (eleganolone, eleganonal and fucosterol) isolated from the brown seaweed Bifurcaria bifurcata. In vitro neuroprotective effects were evaluated on a PD cellular model induced by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y human cells, while lipopolysaccharide (LPS) - stimulated RAW 264.7 macrophages were used to evaluate the anti-inflammatory potential. Additionally, the underlying mechanisms of action were also investigated. Compounds were isolated by preparative chromatographic methods and their structural elucidation attained by NMR spectroscopy. Among the tested compounds, eleganolone (0.1-1 µM; 24 h) reverted the neurotoxicity induced by 6-OHDA in about 20%. The neuroprotective effects were mediated by mitochondrial protection, reduction of oxidative stress, inflammation and apoptosis, and inhibition of NF-kB pathway. The results suggest that eleganolone may provide advantages in the treatment of neurodegenerative conditions and, therefore, should be considered for future preclinical studies.

Unravelling the Anti-Inflammatory and Antioxidant Potential of the Marine Sponge Cliona celata from the Portuguese Coastline.

Inflammation is a double-edged sword, as it can have both protective effects and harmful consequences, which, combined with oxidative stress (OS), can lead to the development of deathly chronic inflammatory conditions. Over the years, research has evidenced the potential of marine sponges as a source of effective anti-inflammatory therapeutic agents. Within this framework, the purpose of this study was to evaluate the antioxidant and the anti-inflammatory potential of the marine sponge Cliona celata. For this purpose, their organic extracts (C1-C5) and fractions were evaluated concerning their radical scavenging activity through 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and anti-inflammatory activity through a (lipopolysaccharides (LPS)-induced inflammation on RAW 264.7 cells) model. Compounds present in the two most active fractions (F5 and F13) of C4 were tentatively identified by gas chromatography coupled to mass spectrometry (GC-MS). Even though samples displayed low antioxidant activity, they presented a high anti-inflammatory capacity in the studied cellular inflammatory model when compared to the anti-inflammatory standard, dexamethasone. GC-MS analysis led to the identification of n-hexadecanoic acid, cis-9-hexadecenal, and 13-octadecenal in fraction F5, while two major compounds, octadecanoic acid and cholesterol, were identified in fraction F13. The developed studies demonstrated the high anti-inflammatory activity of the marine sponge C. celata extracts and fractions, highlighting its potential for further therapeutic applications.

Unravelling the Dermatological Potential of the Brown Seaweed Carpomitra costata.

The ever-increasing interest in keeping a young appearance and healthy skin has leveraged the skincare industry. This, coupled together with the increased concern regarding the safety of synthetic products, has boosted the demand for new and safer natural ingredients. Accordingly, the aim of this study was to evaluate the dermatological potential of the brown seaweed Carpomitra costata. The antioxidant, anti-enzymatic, antimicrobial, photoprotective and anti-inflammatory properties of five C. costata fractions (F1-F5) were evaluated. The ethyl acetate fraction (F3) demonstrated the most promising results, with the best ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals (EC50 of 140.1 µg/mL) and the capacity to reduce reactive oxygen species (ROS) production promoted by UVA and UVB radiation in 3T3 cells, revealing its antioxidant and photoprotective potential. This fraction also exhibited the highest anti-enzymatic capacity, inhibiting the activities of collagenase, elastase and tyrosinase (IC50 of 7.2, 4.8 and 85.9 µg/mL, respectively). Moreover, F3 showed anti-inflammatory potential, reducing TNF-α and IL-6 release induced by LPS treatment in RAW 264.7 cells. These bioactivities may be related to the presence of phenolic compounds, such as phlorotannins, as demonstrated by NMR analysis. The results highlight the potential of C. costata as a source of bioactive ingredients for further dermatological applications.

Loliolide, a New Therapeutic Option for Neurological Diseases? In Vitro Neuroprotective and Anti-Inflammatory Activities of a Monoterpenoid Lactone Isolated from Codium tomentosum.

Parkinsons Disease (PD) is the second most common neurodegenerative disease worldwide, and is characterized by a progressive degeneration of dopaminergic neurons. Without an effective treatment, it is crucial to find new therapeutic options to fight the neurodegenerative process, which may arise from marine resources. Accordingly, the goal of the present work was to evaluate the ability of the monoterpenoid lactone Loliolide, isolated from the green seaweed Codium tomentosum, to prevent neurological cell death mediated by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y cells and their anti-inflammatory effects in RAW 264.7 macrophages. Loliolide was obtained from the diethyl ether extract, purified through column chromatography and identified by NMR spectroscopy. The neuroprotective effects were evaluated by the MTT method. Cells' exposure to 6-OHDA in the presence of Loliolide led to an increase of cells' viability in 40%, and this effect was mediated by mitochondrial protection, reduction of oxidative stress condition and apoptosis, and inhibition of the NF-kB pathway. Additionally, Loliolide also suppressed nitric oxide production and inhibited the production of TNF-α and IL-6 pro-inflammatory cytokines. The results suggest that Loliolide can inspire the development of new neuroprotective therapeutic agents and thus, more detailed studies should be considered to validate its pharmacological potential.

Founder effect of Fabry disease due to p.F113L mutation: Clinical profile of a late-onset phenotype.

BACKGROUND: Knowledge on clinical profiles of late-onset phenotypes of Fabry disease (FD) is essential to better define their natural history. Our study aims to demonstrate a founder effect of FD due to the GLA gene mutation c.337T>C (p.F113L) in the Portuguese region of Guimarães; and to characterize the clinical profile of this late-onset phenotype in a large cohort of genetically related adult patients, living in the same region. METHODS AND RESULTS: FD screening was performed in 150 adult patients with hypertrophic cardiomyopathy (HCM) and found 25 Fabry patients (16.6%). The p.F113L mutation was found in 21 of them, leading to a genealogy study and haplotype analysis of the p.F113L patients. Genealogy research revealed a 12-generation family tree with a common ancestor to p.F113L patients, suggesting a founder effect that was supported by haplotype findings. Pedigree analysis was performed and 120 consecutive p.F113L patients underwent a predefined diagnostic evaluation of FD multiorgan involvement. This late-onset phenotype was characterized by common and/or potentially severe cardiac manifestations (left ventricular hypertrophy 40.8%, atrial fibrillation 5%, non-sustained ventricular tachycardia 12.5%, atrioventricular block 18.3%, bifascicular block 13.4%). Extracardiac manifestations included albuminuria>30 mg/24 h 36.1%, chronic kidney disease≥G3 7.6%, brain white matter lesions 54.4%, stroke 3.3%, sensorineural deafness 44.5%, cornea verticillata 13.9%. Plasma lyso-GB3 was undetectable in females, regardless of clinical manifestations. CONCLUSION: A founder effect of FD due to p.F113L mutation was documented by genealogy and genetics in a Portuguese region. In this late-onset phenotype, although cardiac manifestations carry the highest prognostic impact, extracardiac involvement is common.

Aquaporin-2 and NKCC2 expression pattern in patients with hepatosplenic schistosomiasis.

OBJECTIVE: Schistosoma mansoni infection is considered a public health problem. Glomerular involvement in schistosomiasis is a well-documented complication, especially in hepatosplenic schistosomiasis (HSS). However, renal tubular function is poorly understood. The aim of this study was to investigate, through urinary exosomes, tubular transporters functionally in HSS patients. METHODS: Cross-sectional study of 20 HSS patients who had isolated exosomes from urine samples. Protease inhibitor was added in the urine samples who were immediately frozen at -80 °C for further exosomes isolation. After urine had thawed, urinary exosomes were obtained using extensive vortexing, centrifugation and ultracentrifugation steps of urine. Urinary transporters expression from exosomes was evaluated by western blot, including NHE3, AQP2 and NKCC2. Charge amounts for gel electrophoresis were adjusted by urinary creatinine concentration of each patient to avoid urinary concentration bias. All protein expression of HSS patients was relative to healthy controls. RESULTS: The expression of aquaporin-2 (AQP2) was lower in HSS patients than in controls (46.8 ± 40.7 vs. 100 ± 70.2%, P = 0.03) and the expression of the NKCC2 co-transporter was higher (191.7 ± 248.6 vs. 100 ± 43.6%, P = 0.02). CONCLUSIONS: The decrease of AQP2 and the increase of NKCC2 expression in HSS patients seem to be involved with the inability of urinary concentration in these patients. These data show renal tubular abnormalities in HSS patients without manifest clinical disease.

OBJECTIF: L'infection à Schistosoma mansoni est considérée comme un problème de santé publique. L'atteinte glomérulaire dans la schistosomiase est une complication bien documentée, en particulier dans la schistosomiase hépatosplénique (SH). Cependant, la fonction tubulaire rénale est mal connue. Le but de cette étude était d'étudier, par le biais d'exosomes urinaires, les transporteurs tubulaires fonctionnellement chez les patients atteints de SH. MÉTHODES: Il s'agit d'une étude transversale sur 20 patients atteints de SH qui avaient des exosomes isolés d'échantillons d'urine. Un inhibiteur de protéase a été ajouté dans les échantillons d'urine qui ont été immédiatement congelés à -80°C pour un isolement supplémentaire des exosomes. Après décongélation de l'urine, des exosomes urinaires ont été obtenus en utilisant des étapes étendues de vortex, de centrifugation et d'ultracentrifugation d'urine. L'expression des transporteurs urinaires d'exosomes a été évaluée par western blot, y compris NHE3, AQP2 et NKCC2. Les quantités de charge pour l'électrophorèse sur gel ont été ajustées par la concentration de créatinine urinaire de chaque patient pour éviter un biais de concentration urinaire. Toute expression protéique des patients atteints de SH était relative à celle de témoins sains. RÉSULTATS: L'expression de l'aquaporine-2 (AQP2) était plus faible chez les patients SH que chez les témoins (46,8 ± 40,7 vs 100 ± 70,2%, P = 0,03) et l'expression du co-transporteur NKCC2 était plus élevée (191,7 ± 248,6 vs 100 ± 43,6%, P = 0,16). CONCLUSIONS: La diminution de l'AQP2 et l'augmentation de l'expression de NKCC2 chez les patients SH semblent être impliquées dans l'incapacité de concentration urinaire chez ces patients. Ces données montrent des anomalies tubulaires rénales chez les patients SH sans maladie clinique manifeste.

Cognitive impairment, endothelial biomarkers and mortality in maintenance haemodialysis patients: a prospective cohort study.

BACKGROUND: Haemodialysis (HD) patients have a high prevalence of cardiovascular disease risk factors as well as cognitive impairment. The objective of the present study was to evaluate the interrelationship between cognitive impairment, endothelium-related biomarkers and cardiovascular/non-cardiovascular mortality. METHODS: A total of 216 outpatients were recruited from three centres in a dialysis network in Brazil between June 2016 and June 2019. Sociodemographic and clinical data were obtained by applying a patient questionnaire, reviewing medical records data and conducting patient interviews. Cognitive function was assessed using the Cambridge Cognitive Examination. Plasma endothelium-related biomarkers [syndecan-1, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion protein-1 (VCAM-1) and angiopoietin-2 (AGPT2)] were measured. Patients were followed for 30 months. Cox proportional hazards regression models were used to assess the associations of the cognitive function scores and each endothelium-related biomarker with cardiovascular/non-cardiovascular mortality. RESULTS: Cognitive function was associated with cardiovascular mortality {each standard deviation [SD] better cognitive score was associated with a 69% lower risk for cardiovascular mortality [hazard ratio (HR) 0.31 [95% confidence interval (CI) 0.17-0.58]} but not with non-cardiovascular mortality. Moreover, cognitive function was also correlated with all endothelial-related biomarkers, except VCAM-1. ICAM-1, AGPT2 and syndecan-1 were also associated with cardiovascular mortality. The association between cognitive function and cardiovascular mortality remained significant with no HR value attenuation [fully adjusted HR 0.32 (95% CI 0.16-0.59)] after individually including each endothelial-related biomarker in the Cox model. CONCLUSIONS: In conclusion, cognitive impairment was associated with several endothelium-related biomarkers. Moreover, cognitive impairment was associated with cardiovascular mortality but not with non-cardiovascular mortality, and the association between cognitive impairment and cardiovascular mortality in HD patients was not explained by any of the endothelial-related biomarkers.

Arg-substituted VmCT1 analogs reveals promising candidate for the development of new antichagasic agent.

VmCT1 is an antimicrobial peptide (AMP) isolated from the venom of the scorpion Vaejovis mexicanus with antimicrobial, anticancer and antimalarial activities, which the rational design with Arg-substitution has yielded AMPs with higher antimicrobial activity than VmCT1. Chagas is a neglected tropical disease, becoming the development of new antichagasic agents is urgent. Thus, we aimed to evaluate the antichagasic effect of VmCT1 and three Arg-substituted analogues, as well their action mechanism. Peptides were tested against the epimastigote, trypomastigote, amastigote forms of Trypanossoma cruzi Y strain and against LLC-MK2 mammalian cells. The mechanism of action of these peptides was evaluated by means of flow cytometry and scanning electron microscopy. VmCT1 presented activity against all three forms of T. cruzi, with EC50 against trypomastigote forms of 1.37 µmol L-1 and selectivity index (SI) of 58. [Arg]3-VmCT1, [Arg]7-VmCT1 and [Arg]11-VmCT1 also showed trypanocidal effect, but [Arg]11-VmCT1 had the best effect, being able to decrease the EC50 against trypomastigote forms to 0.8 µmol L-1 and increase SI to 175. Necrosis was cell death pathway of VmCT1, as well [Arg]7-VmCT1 and [Arg]11-VmCT1, such as observed by membrane damage in flow cytometry analyses and scanning-electron-microscopy. In conclusion, [Arg]11-VmCT1 revealed promising as a candidate for new antichagasic therapeutics.

Antichagasic effect of hemocyanin derived from antimicrobial peptides of penaeus monodon shrimp.

Trypanosoma cruzi, the etiological agent of Chagas disease, is responsible for the infection of millions of people worldwide and it is a public health problem, without an effective cure. Four fragments with antimicrobial potential from the hemocyanin of Penaeus monodon shrimp were identified using a computer software AMPA. The present study aimed to evaluate the antichagasic effect of these four peptides (Hmc364-382, Hmc666-678, Hmc185-197 and Hmc476-498). The peptides were tested against the epimastigote, trypomastigote and amastigote forms of Trypanosoma cruzi Y strain (benznidazole-resistant strain) and cytotoxicity in mammalian cells was evaluated against LLC-MK2 lineage cells. Two fragments (Hmc364-382, Hmc666-678) showed activity against the epimastigote and trypomastigote forms and their selectivity index (SI) was calculated. The Hmc364-382 peptide was considered the most promising (SI > 50) one and it was used for further studies, using flow cytometry analyses with specific molecular probes and scanning electron microscopy (SEM). Hmc364-382 was able to induce cell death in T. cruzi through necrosis, observed by loss of membrane integrity in flow cytometry analyses and pore formation in SEM. Overall, Hmc364-382 open perspectives to the development of new antichagasic agents.

Natural Approaches for Neurological Disorders-The Neuroprotective Potential of Codium tomentosum.

Parkinson's disease (PD) is the second most common neurodegenerative disorder, and is characterized by a progressive degeneration of the dopaminergic neurons in the substantianigra. Although not completely understood, several abnormal cellular events are known to be related with PD progression, such as oxidative stress, mitochondrial dysfunction and apoptosis. Accordingly, the aim of this study was to evaluate the neuroprotective effects of Codium tomentosum enriched fractions in a neurotoxicity model mediated by 6-hydroxydopamine (6-OHDA) on SH-SY5Y human cells, and the disclosure of their mechanisms of action. Additionally, a preliminary chemical screening of the most promising bioactive fractions of C. tomentosum was carried out by GC-MS analysis. Among the tested fractions, four samples exhibited the capacity to revert the neurotoxicity induced by 6-OHDA to values higher or similar to the vitamin E (90.11 ± 3.74% of viable cells). The neuroprotective effects were mediated by the mitigation of reactive oxygen species (ROS) generation, mitochondrial dysfunctions and DNA damage, together with the reduction of Caspase-3 activity. Compounds belonging to different chemical classes, such as terpenes, alcohols, carboxylic acids, aldehydes, esters, ketones, saturated and unsaturated hydrocarbons were tentatively identified by GC-MS. The results show that C. tomentosum is a relevant source of neuroprotective agents, with particular interest for preventive therapeutics.