The Existing Drug Nifuroxazide as an Antischistosomal Agent: In Vitro, In Vivo, and In Silico Studies of Macromolecular Targets.

Schistosomiasis is a parasitic disease that afflicts approximately 250 million people worldwide. There is an urgent demand for new antiparasitic agents because praziquantel, the only drug available for the treatment of schistosomiasis, is not universally effective and may derail current progress toward the WHO goal of eliminating this disease as a public health problem by 2030. Nifuroxazide (NFZ), an oral nitrofuran antibiotic, has recently been explored to be repurposed for parasitic diseases. Here, in vitro, in vivo, and in silico studies were conducted to evaluate the activity of NFZ on Schistosoma mansoni. The in vitro study showed significant antiparasitic activity, with 50% effective concentration (EC50) and 90% effective concentration (EC90) values of 8.2 to 10.8 and 13.7 to 19.3 µM, respectively. NFZ also affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg of body weight) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden (~40%). In patent infection, NFZ achieved a high reduction in the number of eggs (~80%), but the drug caused a low reduction in the egg burden of animals with prepatent infection. Finally, results from in silico target fishing methods predicted that serine/threonine kinases could be one of the potential targets for NFZ in S. mansoni. Overall, the present study revealed that NFZ possesses antischistosomal properties, mainly in terms of egg burden reduction in animals with patent S. mansoni infection. IMPORTANCE The increasing recognition of the burden imposed by helminthiasis, associated with the limited therapeutic arsenal, has led to initiatives and strategies to research and develop new drugs for the treatment of schistosomiasis. One of these strategies is drug repurposing, which considers low-risk compounds with potentially reduced costs and shorter time for development. In this study, nifuroxazide (NFZ) was evaluated for its anti-Schistosoma mansoni potential through in vitro, in vivo, and in silico studies. In vitro, NFZ affected worm pairing and egg production and induced severe damage to the tegument of schistosomes. In vivo, a single oral dose of NFZ (400 mg/kg) to mice harboring either prepatent or patent S. mansoni infection significantly reduced the total worm burden and egg production. In silico investigations have identified serine/threonine kinases as a molecular target for NFZ. Collectively, these results implied that NFZ might be a potential therapeutic candidate for the treatment of schistosomiasis.

Salivary biomarkers in Alzheimer´s disease / Biomarcadores salivales en la enfermedad de Alzheimer

The hypotheses currently considered the most likely causes of Alzheimer's disease (AD) are amyloid beta peptide deposition in the cerebral cortex and hyperphosphorylation of the Tau protein, with the consequent formation of neurofibrillary tangles. In clinical practice, although not accurate, AD diagnosis is based on the exclusion of other diseases, behavioural assessments and complementary examinations, such as imaging and blood tests. Advances in the field of biotechnology have created exciting prospects for the early detection of AD via biomarker assessment, which is considered a safer and more efficient procedure. Molecules recognised as biomarkers can be expressed in some body fluids, including cerebrospinal fluid, saliva and blood. The presence of amyloid beta peptide and Tau can be confirmed in saliva, which is also an easily and non-invasively collectable material with an accessible cost. The objective was evaluate the concentrations of the t-Tau protein and Ab42 peptide in the saliva of elderly individuals with and without dementia of the AD type Method: The objective of this case-control study, involving a total of 120 individuals, was to analyse whether a correlation exists between variations in the concentrations of the t-Tau and Ab42 biomarkers in the saliva of patients with confirmed AD and individuals in the inclusion group but without AD . We found that t-Tau expression in AD patients is significantly lower than that in individuals without AD, whereas the salivary concentration of Ab42 is higher in patients with AD but not significantly different from that of the group without AD. Conclusion: Thus, we demonstrate the feasibility of using salivary biomarkers as predictive markers for diagnosis of Alzheimer's disease.

Las hipótesis consideradas actualmente como las causas más probables de la enfermedad de Alzheimer (EA) son la deposición de péptido beta amiloide en la corteza cerebral y la hiperfosforilación de la proteína Tau, con la consiguiente formación de ovillos neurofibrilares. En la práctica clínica, aunque no es precisa, el diagnóstico de la EA se basa en la exclusión de otras enfermedades, evaluaciones de comportamiento y exámenes complementarios, como imágenes y análisis de sangre. Los avances en el campo de la biotecnología han creado interesantes perspectivas para la detección temprana de la EA a través de la evaluación de biomarcadores, que se considera un procedimiento más seguro y más eficiente. Las moléculas reconocidas como biomarcadores se pueden expresar en algunos fluidos corporales, incluidos el líquido cerebroespinal, la saliva y la sangre. La presencia del péptido beta amiloide (AB) y la proteína Tau (t-Tau) se puede confirmar en la saliva, que también es un material fácil y no invasivo de recolección con un costo accesible. El objetivo fue evaluar las concentraciones de la proteína t-Tau y el péptido Ab42 en la saliva de las personas de edad avanzada con y sin demencia del tipo de tipo EA. El estudio de casos y controles, se realizó en un total de 120 personas, para analizar si existe una correlación entre las variaciones en las concentraciones de los biomarcadores t-Tau y Ab42 en la saliva de pacientes con EA confirmada e individuos en el grupo de inclusión pero sin AD. Encontramos que la expresión de t-Tau en pacientes con EA es significativamente menor que en individuos sin EA, mientras que la concentración salival de Ab42 es mayor en pacientes con EA pero no significativamente diferente de la del grupo sin la enfermedad . Por lo tanto, se demuestra la viabilidad del uso de biomarcadores salivales como marcadores predictivos para el diagnóstico de la enfermedad de Alzheimer.

Hypothalamic inhibition of acetyl-CoA carboxylase stimulates hepatic counter-regulatory response independent of AMPK activation in rats.

BACKGROUND: Hypothalamic AMPK acts as a cell energy sensor and can modulate food intake, glucose homeostasis, and fatty acid biosynthesis. Intrahypothalamic fatty acid injection is known to suppress liver glucose production, mainly by activation of hypothalamic ATP-sensitive potassium (K(ATP)) channels. Since all models employed seem to involve malonyl-CoA biosynthesis, we hypothesized that acetyl-CoA carboxylase can modulate the counter-regulatory response independent of nutrient availability. METHODOLOGY/PRINCIPAL FINDINGS: In this study employing immunoblot, real-time PCR, ELISA, and biochemical measurements, we showed that reduction of the hypothalamic expression of acetyl-CoA carboxylase by antisense oligonucleotide after intraventricular injection increased food intake and NPY mRNA, and diminished the expression of CART, CRH, and TRH mRNA. Additionally, as in fasted rats, in antisense oligonucleotide-treated rats, serum glucagon and ketone bodies increased, while the levels of serum insulin and hepatic glycogen diminished. The reduction of hypothalamic acetyl-CoA carboxylase also increased PEPCK expression, AMPK phosphorylation, and glucose production in the liver. Interestingly, these effects were observed without modification of hypothalamic AMPK phosphorylation. CONCLUSION/SIGNIFICANCE: Hypothalamic ACC inhibition can activate hepatic counter-regulatory response independent of hypothalamic AMPK activation.

Solidago chilensis Meyen hydroalcoholic extract reduces JNK/IκB pathway activation and ameliorates insulin resistance in diet-induced obesity mice.

Hydroalcoholic extract of Solidago chilensis (Sc) is employed in popular medicine to treat inflammatory disease. The low-grade proinflammatory state and the activation of serine/threonine kinases in adipose tissue, like c-jun kinase (JNK) and IKK, and transcription factors, have an important role in obesity-associated insulin resistance. The aim of this study was to further investigate the effects of the Sc extract on glucose homeostasis in diet-induced obesity mice. Male Swiss mice were randomized to three groups: a control group (C) fed with standard laboratory chow; a group with an experimental high-fat diet (HFD); and a group fed with a high-fat (45% kcal from fat) diet + extract of Sc (via intraperitoneal, 3 mg/kg) (ScHFD). The dietary treatment lasted for eight weeks. Subsequently, the expression and phosphorylation of proteins of interest in the liver, hypothalamus and skeletal muscle were evaluated by Western blot analysis. Body weight, epididymal fat pad mass and liver triglycerides were higher in HFD than in control mice, but these parameters were reduced by intraperitoneal administration of the extracts (3 mg/kg) to the HFD group. AKT phosphorylation stimulated by insulin in the liver, hypothalamus and skeletal muscle was higher in ScHFD as compared with HFD mice. Additionally, liver expression of phosphoenolpyruvate carboxykinase (PEPCK) and fatty acid synthase were lower in ScHFD as compared with HFD mice. Nuclear factor κB, p-IκB and p-JNK levels were higher in HFD when compared with control mice, but they were lowered by treatment with extract (ScHFD). In addition, in db/db mice, Sc extract also improved liver AKT phosphorylation stimulated by insulin and reduced PEPCK expression. The data presented herein show that Sc improves AKT activation. This effect may be promoted by reduction of the proinflammatory pathway in the liver and hypothalamus. Therefore, systemic action of the Sc components may contribute to improve obesity-associated pathophysiology.

Synthesis and acetylcholinesterase inhibitory activity of 2ß,3α-disulfoxy-5α-cholestan-6-one.

Disodium 2ß,3α-dihydroxy-5α-cholestan-6-one disulfate (8) has been synthesized using cholesterol (1) as starting material. Sulfation was performed using trimethylamine-sulfur trioxide complex in dimethylformamide as the sulfating agent. The acetylcholinesterase inhibitory activity of compound 8 was evaluated and compared to that of disodium 2ß,3α-dihydroxy-5α-cholestane disulfate (10) and diols 7 and 9. Compounds 8 and 10 were active with IC(50) values of 14.59 and 59.65 µM, respectively. Diols 7 and 9 showed no inhibitory activity (IC(50)>500 µM).

Central leptin action improves skeletal muscle AKT, AMPK, and PGC1 alpha activation by hypothalamic PI3K-dependent mechanism.

Central leptin action requires PI3K activity to modulate glucose homeostasis and peripheral metabolism. However, the mechanism behind this phenomenon is not clearly understood. We hypothesize that hypothalamic PI3K activity is important for the modulation of the AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) pathway, PGC1 alpha, and AKT in skeletal muscle (SM). To address this issue, we injected leptin into the lateral ventricle of rats. Hypothalamic JAK2 and AKT were activated by intracerebroventricular (ICV) injection of leptin in a time-dependent manner. Central leptin improved tolerance to glucose (GTT), increased PGC1 alpha expression, and AKT, AMPK, ACC and JAK2 phosphorylation in the soleus muscle. Previous ICV administration of either LY294002 or propranolol (IP) blocked these effects. We concluded that the activation of the hypothalamic PI3K pathway is important for leptin-induced AKT phosphorylation, as well as for active catabolic pathway through AMPK and PGC1 alpha in SM. Thus, a defective leptin signalling PI3K pathway in the hypothalamus may contribute to peripheral resistance to insulin associated to diet-induced obesity.

Synthesis and antiviral activity of sulfated and acetylated derivatives of 2beta,3alpha-dihydroxy-5alpha-cholestane.

Five new steroid sulfates, sodium 2beta,3alpha-dihydroxy-5alpha-cholestane 3-sulfate (6), sodium 2beta,3alpha-dihydroxy-5alpha-cholestane 2-sulfate (7), disodium 2beta,3alpha-dihydroxy-5alpha-cholestane disulfate (8), sodium 3alpha-acetoxy-2beta-hydroxy-5alpha-cholestane 2-sulfate (12), and sodium 2beta-acetoxy-3alpha-hydroxy-5alpha-cholestane 3-sulfate (13), have been synthesized starting from 3beta-hydroxy-5alpha-cholestane (1). The synthetic steroids were completely characterized by one-dimensional and two-dimensional NMR and FABMS spectra. Sulfation was performed using triethylamine-sulfur trioxide complex in dimethylformamide as the sulfating agent. The sulfated steroids were comparatively evaluated for their inhibitory effect on the replication of herpes simplex virus type 2 (HSV-2). Compounds 7 and 8 were the most effective in their inhibitory action against HSV-2. The disulfated steroid 8 also proved to be active against DEN-2 and JV.

Surdez súbita: tratamento exclusivo com pentoxifilina oral. Relato de caso / Sudden deafness: exclusive treatment with oral pentoxifylline. Case report

Objetivo: Relatar casos que mostram a eficácia do uso exclusivo da pentoxifilina por via oral no tratamento da surdez súbita de etiologia näo definida. Método: Dez casos de surdez súbita sem etiologia conhecida foram tratados exclusivamente com pentoxifilina 400 mg via oral (1200mg/dia). Quatro eram do sexo feminino e seis do sexo masculino com idade média entre 40 e 70 anos. Resultados: As audiometrias seriadas demonstraram diferentes respostas individuais, com melhora audiométrica de todos os casos. Conclusäo: A surdez súbita pode ser tratada ambulatorialmente, com economia, segurança e bons resultados.