Martin Krähenbühl Amstalden
@usp.br
Department of Clinical Analyses, Toxicology and Food Science
School of Pharmaceutical Sciences of Ribeirão Preto
EDUCATION
(2013-2017) Bachelor in Pharmacy-Biochemistry: FCFRP-USP
(2018-) Masters in Biosciences and Biotechnology
RESEARCH INTERESTS
Glicobiology, Immunology and Biochemistry. Galectins, bacteria.
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Susanne Brenzinger, Martina Airoldi, Adewale Joseph Ogunleye, Karl Jugovic, Martin Krähenbühl Amstalden, and Ana Rita Brochado
Springer Science and Business Media LLC
Carolina P. Bernardes, Neife A. G. Santos, Tassia R. Costa, Danilo L. Menaldo, Flavia M. Sisti, Martin K. Amstalden, Diego L. Ribeiro, Lusânia M. G. Antunes, Suely V. Sampaio, and Antonio C. Santos
Springer Science and Business Media LLC
Carlos A. Fuzo, Ronaldo B. Martins, Thais F. C. Fraga‐Silva, Martin K. Amstalden, Thais Canassa De Leo, Juliano P. Souza, Thais M. Lima, Lucia H. Faccioli, Débora Noma Okamoto, Maria Aparecida Juliano,et al.
Wiley
The global emergence of coronavirus disease 2019 (COVID-19) has caused substantial human casualties. Clinical manifestations of this disease vary from asymptomatic to lethal, and the symptomatic form can be associated with cytokine storm and hyperinflammation. In face of the urgent demand for effective drugs to treat COVID-19, we have searched for candidate compounds using in silico approach followed by experimental validation. Here we identified celastrol, a pentacyclic triterpene isolated from Tripterygium wilfordii Hook F, as one of the best compounds out of 39 drug candidates. Celastrol reverted the gene expression signature from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected cells and irreversibly inhibited the recombinant forms of the viral and human cysteine proteases involved in virus invasion, such as Mpro (main protease), PLpro (papain-like protease), and recombinant human cathepsin L. Celastrol suppressed SARS-CoV-2 replication in human and monkey cell lines and decreased interleukin-6 (IL-6) secretion in the SARS-CoV-2-infected human cell line. Celastrol acted in a concentration-dependent manner, with undetectable signs of cytotoxicity, and inhibited in vitro replication of the parental and SARS-CoV-2 variant. Therefore, celastrol is a promising lead compound to develop new drug candidates to face COVID-19 due to its ability to suppress SARS-CoV-2 replication and IL-6 production in infected cells.
Stellee M. P. Biscaia, Cassiano Pires, Francislaine A. R. Lívero, Daniel L. Bellan, Israel Bini, Silvina O. Bustos, Renata O. Vasconcelos, Alexandra Acco, Marcello Iacomini, Elaine R. Carbonero,et al.
International Journal of Molecular Sciences MDPI AG
Melanoma is a highly metastatic and rapidly progressing cancer, a leading cause of mortality among skin cancers. The melanoma microenvironment, formed from the activity of malignant cells on the extracellular matrix and the recruitment of immune cells, plays an active role in the development of drug resistance and tumor recurrence, which are clinical challenges in cancer treatment. These tumoral metabolic processes are affected by proteins, including Galectin-3 (Gal-3), which is extensively involved in cancer development. Previously, we characterized a partially methylated mannogalactan (MG-Pe) with antimelanoma activities. In vivo models of melanoma were used to observe MG-Pe effects in survival, spontaneous, and experimental metastases and in tissue oxidative stress. Analytical assays for the molecular interaction of MG-Pe and Gal-3 were performed using a quartz crystal microbalance, atomic force microscopy, and contact angle tensiometer. MG-Pe exhibits an additive effect when administered together with the chemotherapeutic agent dacarbazine, leading to increased survival of treated mice, metastases reduction, and the modulation of oxidative stress. MG-Pe binds to galectin-3. Furthermore, MG-Pe antitumor effects were substantially reduced in Gal-3/KO mice. Our results showed that the novel Gal-3 ligand, MG-Pe, has both antitumor and antimetastatic effects, alone or in combination with chemotherapy.
Mônica Soares Costa, Yasmim Garcia Gonçalves, Bruna Cristina Borges, Marcelo José Barbosa Silva, Martin Krähenbühl Amstalden, Tássia Rafaella Costa, Lusânia Maria Greggi Antunes, Renata Santos Rodrigues, Veridiana de Melo Rodrigues, Eduardo de Faria Franca,et al.
Springer Science and Business Media LLC
Abstract Ruthenium complexes have been extensively explored as potential molecules for cancer treatment. Considering our previous findings on the remarkable cytotoxic activity exhibited by the ruthenium (II) complex 3-hydroxy-4-methoxybenzoate (hmxbato)-cis-[RuII(ŋ2-O2CC7H7O2)(dppm)2]PF6 against Leishmania promastigotes and also the similar metabolic characteristics between trypanosomatids and tumor cells, the present study aimed to analyze the anticancer potential of hmxbato against lung tumor cells, as well as the partial death mechanisms involved. Hmxbato demonstrated selective cytotoxicity against A549 lung tumor cells. In addition, this complex at a concentration of 3.8 µM was able to expressively increase the generation of reactive oxygen species (ROS) in tumor cells, causing an oxidative stress that may culminate in: (1) reduction in cellular proliferation; (2) changes in cell morphology and organization patterns of the actin cytoskeleton; (3) cell arrest in the G2/M phase of the cell cycle; (4) apoptosis; (5) changes in the mitochondrial membrane potential and (6) initial DNA damage. Furthermore, we demonstrated that the induction of programmed cell death can occur by the intrinsic apoptotic pathway through the activation of caspases. It is also worth highlighting that hmxbato exhibited predominant actions on A549 tumor cells in comparison to BEAS-2B normal bronchial epithelium cells, which makes this complex an interesting candidate for the design of new drugs against lung cancer.
Carolina P. Bernardes, Neife A. G. Santos, Tassia R. Costa, Flavia Sisti, Lilian Amaral, Danilo L. Menaldo, Martin K. Amstalden, Diego L. Ribeiro, Lusânia M.G. Antunes, Suely Vilela Sampaio,et al.
Springer Science and Business Media LLC
The synthetic peptide p-BTX-I is based on the native peptide (formed by glutamic acid, valine and tryptophan) isolated from Bothrops atrox venom. We have previously demonstrated its neuroprotective and neurotrophic properties in PC12 cells treated with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Now, we have investigated the neuroprotective effects and mechanisms of p-BTX-I against the toxicity of acrolein in PC12 cells. Studies have demonstrated that acrolein might play an important role in the etiology of Alzheimer’s disease (AD), which is characterized by neuronal and synaptic loss. Our results showed that not only acrolein reduced cell differentiation and cell viability, but also altered the expression of markers of synaptic communication (synapsin I), energy metabolism (AMPK-α, Sirt I and glucose uptake), and cytoskeleton (β-III-tubulin). Treatment with p-BTX-I increased the percentage of differentiation in cells treated with acrolein and significantly attenuated cell viability loss, besides counteracting the negative effects of acrolein on synapsin I, AMPK-α, Sirt I, glucose uptake, and β-III-tubulin. Additionally, p-BTX-I alone increased the expression of apolipoprotein E (apoE) gene, associated with the proteolytic degradation of β-amyloid peptide aggregates, a hallmark of AD. Taken together, these findings demonstrate that p-BTX-I protects against acrolein-induced neurotoxicity and might be a tool for the development of novel drugs for the treatment of neurodegenerative diseases.
Tássia R. Costa, Martin K. Amstalden, Diego L. Ribeiro, Danilo L. Menaldo, Marco A. Sartim, Alexandre F. Aissa, Lusânia M.G. Antunes, and Suely V. Sampaio
Elsevier BV
Snake venom L-amino acid oxidases (SV-LAAOs) are enzymes of great interest in research due to their many biological effects with therapeutic potential. CR-LAAO, an L-amino acid oxidase from Calloselasma rhodostoma snake venom, is a well described SV-LAAO with immunomodulatory, antiparasitic, microbicidal, and antitumor effects. In this study, we evaluated the genotoxic potential of this enzyme in human peripheral blood mononuclear cells (PBMC) and HepG2 tumor cells, as well as its interaction with these cells, its impact on the expression of DNA repair and antioxidant pathway genes, and reactive oxygen species (ROS)-induced intracellular production. Flow cytometry analysis of FITC-labelled CR-LAAO showed higher specificity of interaction with HepG2 cells than PBMC. Moreover, CR-LAAO significantly increased intracellular levels of ROS only in HepG2 tumor cells, as assessed by fluorescence. CR-LAAO also induced genotoxicity in HepG2 cells and PBMC after 4 h of stimulus, with DNA damages persisting in HepG2 cells after 24 h. To investigate the molecular basis underlying the genotoxicity attributed to CR-LAAO, we analyzed the expression profile (mRNA levels) of 44 genes involved in DNA repair and antioxidant pathways in HepG2 cells by RT2 Profiler polymerase chain reaction array. CR-LAAO altered the tumor cell expression of DNA repair genes, with two downregulated (XRCC4 and TOPBP1) and three upregulated (ERCC6, RAD52 and CDKN1) genes. In addition, two genes of the antioxidant pathway were upregulated (GPX3 and MPO), probably in an attempt to protect tumor cells from oxidative damage. In conclusion, our data suggest that CR-LAAO possesses higher binding affinity to HepG2 tumor cells than to PBMC, its genotoxic mechanism is possibly caused by the oxidative stress related to the production of H2O2, and is also capable of modulating genes related to the DNA repair system and antioxidant pathways.