Alan Almeida Veiga

Mr. Alan Almeida Veiga

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Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 June 2022 in Pharmaceuticals
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Journal Article
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AVAlan Almeida Veiga
Alan Almeida Veiga
AIAna Carolina Irioda
Ana Carolina Irioda
BMBassam Mogharbel
Bassam Mogharbel
SBSANDRO JOSE RIBEIRO BONATTO
SANDRO JOSE RIBEIRO BONATTO
LSLauro M. Souza
Lauro M. Souza
Adrenocortical carcinoma (ACC) is a rare subtype of cancer, with a poor prognosis in children and adults. Mitotane is the only approved adrenolytic drug for the treatment of ACC, which has controversies regarding its efficacy and side effects on patients. Onion (Allium cepa), a worldwide consumed food, is associated with many health benefits. Along with its glycosides, the flavonoid quercetin is abundant in onions. After evaluating the cytotoxicity of A. cepa extracts on adrenocortical carcinoma cell line (H295R), the rich quercetin fractions had better results. Then, we aimed to compare the quercetin vs. mitotane effectiveness, using adrenocortical carcinoma cell lines H295R and SW-13. Quercetin showed a higher cytotoxicity response on both cancerous cell lines after 10 µM concentration, while mitotane only after 30 µM. Cell cycle dynamics were altered upon quercetin treatments, with G2 phase increase with 30 µM of quercetin on H295R cell line and G1 arrest on SW-13 cell line with 15 µM. Early and late apoptosis, alongside intracellular calcium, were increased on SW-13 treated with 30 µM of quercetin, and ROS rates were reduced by quercetin on H295R. Therefore, quercetin-rich onions have the potential to be a natural source of anticancer agents for adrenocortical carcinoma.

1 January 2022 in Journal of Food Composition and Analysis
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Journal Article
Closed access
GSGabriel Selonke dos Santos
Gabriel Selonke dos Santos
AVAlan Almeida Veiga
Alan Almeida Veiga
JCJuliane Carlotto
Juliane Carlotto
RMRosiane Guetter Mello
Rosiane Guetter Mello
RSRodrigo Vassoler Serrato
Rodrigo Vassoler Serrato
LSLauro M. Souza
Lauro M. Souza

15 November 2021 in Evidence-Based Complementary and Alternative Medicine
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PZPriscila Megda João Job Zago
Priscila Megda João Job Zago
GSGustavo Ratti Da Silva
Gustavo Ratti Da Silva
EAEduarda Carolina Amaral
Eduarda Carolina Amaral
LBLorena Neris Barboza
Lorena Neris Barboza
FBFernanda de Abreu Braga
Fernanda de Abreu Braga
Francislaine Aparecida dos Reis LíveroFrancislaine Aparecida dos Reis Lívero
Francislaine Aparecida dos Reis Lívero
Croton urucurana Baill. is a native Brazilian tree, popularly known as sangra-dágua or sangue-de-dragão, based on the red resinous sap of the trunk. Its use has been transmitted through generations based on popular tradition that attributes analgesic, anti-inflammatory, and cardioprotective properties to the tree. However, its cardioprotective effects have not yet been scientifically investigated. Thus, the present study investigated the pharmacological response to an ethanol-soluble fraction from the leaves of C. urucurana in Wistar rats exposed to smoking and dyslipidemia, two important cardiovascular risk factors. The extract was evaluated by high-performance liquid chromatography. Wistar rats received a 0.5 cholesterol-enriched diet and were exposed to cigarette smoke (9 cigarettes/day for 10weeks). During the last 5weeks, the animals were orally treated with vehicle (negative control group), C. urucurana extract (30, 100, and 300mg/kg), or simvastatin (2.5mg/kg)+enalapril (15mg/kg). One group of rats that was not exposed to these risk factors was also evaluated (basal group). Electrocardiograms and systolic, diastolic, and mean blood pressure were measured. Blood was collected to measure total cholesterol, triglycerides, urea, and creatinine. The heart and kidneys were collected and processed for oxidative status and histopathological evaluation. The phytochemical analysis revealed different classes of flavonoids and condensed tannins. The model induced dyslipidemia and cardiac and renal oxidative stress and increased levels of urea and creatinine in the negative control group. Treatment with the C. urucurana extract (300mg/kg) and simvastatin+enalapril decreased cholesterol and triglyceride levels. In contrast to simvastatin+enalapril treatment, the C. urucurana extract exerted cardiac and renal antioxidant effects. No alterations of electrocardiograms, blood pressure, or histopathology were observed between groups. These findings indicate that C. urucurana exerts lipid-lowering, renal, and cardioprotective effects against oxidative stress in a preclinical model of multiple risk factors for heart disease.

13 September 2022 in Molecules
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MMMariana Inocencio Manzano
Mariana Inocencio Manzano
ACAriana Centa
Ariana Centa
AVAlan Almeida Veiga
Alan Almeida Veiga
NCNayara Souza da Costa
Nayara Souza da Costa
SBSANDRO JOSE RIBEIRO BONATTO
SANDRO JOSE RIBEIRO BONATTO
Fhernanda Ribeiro SmiderleFhernanda Ribeiro Smiderle
Fhernanda Ribeiro Smiderle
The plant Miconia albicans (Sw.) Triana has been popularly used in Brazil to treat chronic inflammatory disturbances, such as osteoarthritis. This disease affects 250 million people worldwide, and is associated with intense pain and loss of articular function. There is a lack of information about the phytochemistry and bioactivity of M. albicans. Therefore, this study determined the chemical composition of some extracts and evaluated their cytotoxicity, along with their antioxidant and anti-inflammatory, activities using in vitro models. Aqueous and ethanolic extracts were prepared. Afterwards, a liquid–liquid partition was developed using chloroform, ethyl acetate, and n-butanol. The extracts were characterized by LC–MS, and their biological activities were evaluated on epithelial cells (Vero), tumoral hepatic cells (Hep-G2), and THP-1 macrophages. LC–MS analyses identified several flavonoids in all fractions, such as quercetin, myricetin, and their glycosides. The crude extracts and n-butanol fractions did not present cytotoxicity to the cells. The non-toxic fractions presented significant antioxidant activity when evaluated in terms of DPPH scavenging activity, lipid peroxidation, and ROS inhibition. THP-1 macrophages treated with the n-butanol fraction (250 µg/mL) released fewer pro-inflammatory cytokines, even in the presence of LPS. In the future, it will be necessary to identify the phytochemicals that are responsible for anti-inflammatory effects for the discovery of new drugs. In vivo studies on M. albicans extracts are still required to confirm their possible mechanisms of action.

29 November 2022 in Pharmaceuticals
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Journal Article
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CBCamila Bach
Camila Bach
CCClaudia Corso
Claudia Corso
AVAlan Almeida Veiga
Alan Almeida Veiga
MPMariana Martins Paraizo
Mariana Martins Paraizo
LSLauro M. Souza
Lauro M. Souza
In South Brazil, the incidence of pediatric adrenocortical carcinoma (ACC) is higher than in other regions and countries worldwide. The ACC treatment includes therapy with mitotane, the only adrenolytic drug approved by the FDA. The mitotane metabolism occurs via two main reactions: the β-hydroxylation, which yields the final product o,p’-DDA, and the α-hydroxylation, which will give the final product o,p’-DDE. It is speculated that o,p’-DDE may be an active metabolite since it has a cytotoxic effect on adrenocortical carcinoma cells (H295R). No further studies have been conducted to confirm this hypothesis; however, it was found that mitotane and its metabolites are present at significantly different concentrations in the plasma of the patients. Our study aimed to assess the in vitro effects of o,p’-DDE and o,p’-DDD in cell death pathways, oxidative parameters, and interaction with adrenal CYP’s involved in the steroidogenic process in the H295R cell line. It was found that o,p’-DDE had a different effect than the o,p’-DDD on apoptosis, inhibiting this cell death pathway, but it promotes cell necrosis at higher concentrations. In contrast to o,p’-DDD, the o,p’-DDE did not have effects on the different oxidative parameters evaluated, but exhibited stimulatory interactions with steroidogenic CYP’s, at intermediate concentrations. Therefore, we demonstrated important cell effects of o,p’-DDE; its plasma levels during mitotane therapy should be monitored as an important therapeutic parameter.

23 December 2025 in Pharmaceuticals
Verified
Journal Article
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EAEduarda Carolina Amaral
Eduarda Carolina Amaral
AVAlan Almeida Veiga
Alan Almeida Veiga
JAJuliana Campos Atherino
Juliana Campos Atherino
WSWesley M. de Souza
Wesley M. de Souza
DKDiogo Kita
Diogo Kita
LSLauro M. Souza
Lauro M. Souza
Background/Objectives:Pereskia aculeata and Pereskia grandifolia belong to the Cactaceae family, despite their foliar and woody stem characteristics. Both species are commonly known as Ora-pro-nóbis (derived from Latin, meaning “pray for us”), a name rooted in their historical use in colonial Brazil due to their nutritional value, particularly P. aculeata, which is frequently described as a high-protein food source. The goal of the present study was to compare these species based on phytochemical composition and antioxidant capacity. Methods: Both species were investigated for their chemical antioxidant properties (DPPH and phosphomolybdenum complex) and cellular anti-ROS activity using the CACO-2 cell line. A comprehensive phytochemical analysis was performed using LC-MS and GC-MS. Results: P. aculeata exhibited a more abundant content of phenolics and flavonoids, with greater structural variability in phenolic compounds and glycosylated flavonoids than P. grandifolia. Still, P. aculeata showed a more potent chemical antioxidant effect. By contrast, in P. grandifolia, a series of novel saponins was now discovered and characterized. In addition, the compounds from this species exhibited a greater cellular antioxidant activity than those of P. aculeata. Tryptophan-derived alkaloids, such as abrine (N-methyltryptophan), were present in both species, but hypaphorine only in P. aculeata. Conclusions: Both species of Pereskia exhibit potential health benefits, including distinct antioxidant activity, among other unexplored effects, given their significant variability in phytochemicals. These differences could be investigated in greater depth using combined LC-MS and GC-MS, thereby enabling more confident structural investigations of these natural compounds.