Publications by authors named "Antonio Cardozo dos Santos"

Background: Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. There is no effective treatment for neurodegenerative diseases. Snake venoms are a cocktail of proteins and peptides with great therapeutic potential and might be useful in the treatment of neurodegenerative diseases.

View Article and Find Full Text PDF

Artepillin C is the most studied compound in Brazilian Green Propolis and, along with its acetylated derivative, displays neurotrophic activity on PC12 cells. Specific inhibitors of the trkA receptor (K252a), PI3K/Akt (LY294002), and MAPK/ERK (U0126) signaling pathways were used to investigate the neurotrophic mechanism. The expression of proteins involved in axonal and synaptic plasticity (GAP-43 and Synapsin I) was assessed by western blotting.

View Article and Find Full Text PDF

Doxycycline (DOX) is a widely used antibiotic that is able to cross the blood-brain barrier. Several studies have shown its neuroprotective effect against neurodegeneration and have associated it with antioxidant, anti-apoptotic, and anti-inflammatory mechanisms. We have recently demonstrated that DOX mimics nerve growth factor (NGF) signaling in PC12 cells.

View Article and Find Full Text PDF
Article Synopsis
  • * Baccharin, a small molecule derived from Brazilian green propolis, shows potential neurotrophic and neuroprotective effects in a PC12 neuronal model, stimulating neuritogenesis similar to NGF by activating specific signaling pathways (trkA, PI3K/Akt, and MAPK/ERK).
  • * The study found that baccharin enhances the expression of proteins crucial for axonal (GAP-43) and synaptic (synapsin I) function, indicating its
View Article and Find Full Text PDF

Doxycycline has been used as antibiotic since the 1960s. Recently, studies have shown that doxycycline is neuroprotective in models of neurodegenerative diseases and brain injuries, mainly due to anti-inflammatory and anti-apoptotic effects. However, it is not known if doxycycline has neurotrophic potential, which is relevant, considering the role of axonal degeneration at the early stages of neurodegeneration in Alzheimer's disease, Amyotrophic Lateral Sclerosis and Parkinson's disease as well as in normal aging.

View Article and Find Full Text PDF
Article Synopsis
  • * This study explored CARV's potential to enhance axonal and synaptic plasticity, important for cognition and memory, by using a PC12 cell model, revealing its ability to promote neurite outgrowth via the trkA receptor and related signaling pathways.
  • * CARV was found to boost the expression of proteins linked to neuronal plasticity and improve cellular energy levels, suggesting it could have therapeutic benefits for conditions such as Parkinson's and Alzheimer's diseases.
View Article and Find Full Text PDF

Objectives: To investigate S-adenosyl-methyonine (SAM) effects on PC12 cells viability and neuritogenesis treated with MPP+ (1-methyl-4-phenylpyridinium).

Methods: PC12 cell viability test (MTT assay) in DMEM medium with SAM and/or MPP+; PC12 cell neuritogenesis test in F-12K medium with nerve growth factor (NGF); DNMT activity in PC12 cells (DNMT Activity Assay Kit) with SAM and/or MPP+.

Key Findings: (1) MPP+ decreased cell viability; (2) SAM did not affect cell viability per se, but it increased MPP+ neurotoxicity when co-incubated with the neurotoxin, an effect abolished by DNA methyltransferases (DNMT) inhibitors; (3) pretreatment with SAM for 30 min or 24 h before MPP+ addition had no effect on cell viability.

View Article and Find Full Text PDF

Cisplatin has dramatically improved the survival rate of cancer patients, but it has also increased the prevalence of hearing and neurological deficits in this population. Cisplatin induces ototoxicity, peripheral (most prevalent) and central (rare) neurotoxicity. This review addresses the ototoxicity and the neurotoxicity associated with cisplatin-based chemotherapy, providing an integrated view of the potential protective agents that have been evaluated in vitro, in vivo and in clinical trials, their targets and mechanisms of protection and their effects on the antitumor activity of cisplatin.

View Article and Find Full Text PDF

Peripheral sensory neuropathy (PSN) is a well-known side effect of cisplatin characterized by axonal damage. In the early stage of neurotoxicity, cisplatin affects proteins that modulate neurite outgrowth and neuroplasticity, without inducing mitochondrial damage or apoptosis. There are no preventive therapies for cisplatin-induced peripheral neuropathy; therefore, measures to improve axonal growth and connectivity would be beneficial.

View Article and Find Full Text PDF

Organophosphorus (OPs) compounds have been widely used in agriculture, industry, and household, and the neurotoxicity induced by them is still a cause of concern. The main toxic mechanism of OPs is the inhibition of acetylcholinesterase (AChE); however, the delayed neuropathy induced by OPs (OPIDN) is mediated by other mechanisms such as the irreversible inhibition of 70% of NTE activity (neuropathy target esterase) that leads to axonal degeneration. Liraglutide is a long-lasting GLP-1 analog clinically used as antidiabetic.

View Article and Find Full Text PDF

Cisplatin is a highly effective chemotherapeutic drug that is toxic to the peripheral nervous system. Findings suggest that axons are early targets of the neurotoxicity of cisplatin. Although many compounds have been reported as neuroprotective, there is no effective treatment against the neurotoxicity of cisplatin.

View Article and Find Full Text PDF

Some organophosphorus compounds (OP), including the pesticide mipafox, produce late onset distal axonal degeneration, known as organophosphorus-induced delayed neuropathy (OPIDN). The underlying mechanism involves irreversible inhibition of neuropathy target esterase (NTE) activity, elevated intracellular calcium levels, increased activity of calcium-activated proteases and impaired neuritogenesis. Voltage-gated calcium channels (VGCC) appear to play a role in several neurologic disorders, including OPIDN.

View Article and Find Full Text PDF

Some organophosphorus compounds (OPs) induce a neurodegenerative disorder known as organophosphate-induced delayed neuropathy (OPIDN), which is related to irreversible inhibition of neuropathy target esterase (NTE) and impairment of neurite outgrowth. The present study addresses the effects of trichlorfon, mipafox (neuropathic model) and paraoxon (non-neuropathic model) on neurite outgrowth and neuroplasticity-related proteins in retinoic-acid-stimulated SH-SY5Y cells, a cellular model widely used to study the neurotoxicity of OPs. Mipafox (20μM) decreased cellular differentiation and the expression of neurofilament 200 (NF-200), growth associated- (GAP-43) and synaptic proteins (synapsin I and synaptophysin); whereas paraoxon (300μM) induced no effect on cellular differentiation, but significant decrease of NF-200, GAP-43, synapsin I and synaptophysin as compared to controls.

View Article and Find Full Text PDF

Cisplatin is the most effective and neurotoxic platinum chemotherapeutic agent. It induces a peripheral neuropathy characterized by distal axonal degeneration that might progress to degeneration of cell bodies and apoptosis. Most symptoms occur nearby distal axonal branches and axonal degeneration might induce peripheral neuropathy regardless neuronal apoptosis.

View Article and Find Full Text PDF

Cisplatin (Cisp) is an effective antitumor drug; however, it causes severe nephrotoxicity. Minimization of renal toxicity is essential, but the interference of nephroprotective agents, particularly antioxidants, with the antitumor activity of cisplatin is a general concern. We have recently demonstrated that the anti-hypertensive and antioxidant drug carvedilol (CV) protects against the renal damage and increases the survival of tumor-bearing mice without impairing the tumor reduction by cisplatin.

View Article and Find Full Text PDF

Organophosphorus-induced delayed neuropathy (OPIDN) is a central-peripheral distal axonopathy that develops 8-14 days after poisoning by a neuropathic organophosphorus compound (OP). Several OPs that caused OPIDN were withdrawn from the agricultural market due to induction of serious delayed effects. Therefore, the development of in vitro screenings able to differentiate neuropathic from non-neuropathic OPs is of crucial importance.

View Article and Find Full Text PDF

Both types of diabetes are associated with higher incidence of some types of cancer. Treating cancer in diabetic patients without aggravating diabetes-related complications is a challenge for clinicians. Additionally, little is known about how diabetes affects the treatment of cancer.

View Article and Find Full Text PDF

Organophosphorus-induced delayed neuropathy (OPIDN) is a central and peripheral distal axonopathy characterized by ataxia and paralysis. Trichlorfon and acephate are two organophosphorus compounds (OPs) used worldwide as insecticide and which cause serious effects to non-target species. Despite that, the neuropathic potential of these OPs remains unclear.

View Article and Find Full Text PDF

Neurite loss is an early event in neurodegenerative diseases; therefore, the regeneration of the network of neurites constitutes an interesting strategy of treatment for such disorders. Neurotrophic factors play a critical role in neuronal regeneration, but their clinical use is limited by their inability to cross the blood brain barrier. Oxidative and inflammatory events are implicated in neurodegeneration and antioxidant compounds have been suggested as potential neuroprotectors.

View Article and Find Full Text PDF

Cisplatin is an effective anticancer drug which has been used to treat a wide range of tumors for the last 30 years. However, its use is associated with nephrotoxicity. Protective strategies have been reported, but their impact on the antitumor activity of cisplatin has not been clarified.

View Article and Find Full Text PDF

Cisplatin is a highly effective antitumor agent whose clinical application is limited by the inherent nephrotoxicity. The current measures of nephroprotection used in patients receiving cisplatin are not satisfactory, and studies have focused on the investigation of new possible protective strategies. Many pathways involved in cisplatin nephrotoxicity have been delineated and proposed as targets for nephroprotection, and many new potentially protective agents have been reported.

View Article and Find Full Text PDF

Bixin is the main carotenoid found in annatto seeds (Bixa orellana L.) and is responsible for their reddish-orange color. The antioxidant properties of this compound are associated with its ability to scavenge free radicals, which may reduce damage and protect tissues against toxicity caused by anticancer drugs such as cisplatin.

View Article and Find Full Text PDF

Neurotoxicity induced by reactive oxygen species can appear as an adverse effect of chemotherapy treatment with platinum compounds, such as cisplatin. The use of this drug in clinical practice is limited due to its adverse effects, including nephrotoxicity, ototoxicity, neurotoxicity and genotoxicity. Functional foods or nutraceuticals have demonstrated potential neuroprotective activity in several experiments and models.

View Article and Find Full Text PDF

PDT has been used in the treatment of malignant brain tumors for the last 2 decades. It is based on the interaction of a photosensitizer (PS) and light of an appropriate wavelength, with generation of oxygen species, mainly singlet oxygen. Brain is particularly susceptible to oxidative stress; therefore the study of PDT effects on cerebral mitochondria might provide mechanistic insights into the action of the therapy, contributing to its optimization.

View Article and Find Full Text PDF

Cisplatin is one of the most effective chemotherapeutic agents. However, at higher doses liver injury may occur. The purpose of this study was to explore whether the hydroxyl radical scavenger dimethylthiourea (DMTU) protects against cisplatin-induced oxidative damage in vivo and to define the mitochondrial pathways involved in cytoprotection.

View Article and Find Full Text PDF