Michele Debiasi Alberton

This study investigated the phytochemical composition, antibacterial, antibiofilm, synergistic, and cytotoxic effects of hydroethanolic extracts and fractions from Eugenia astringens and Eugenia mattosii . HPLC–ESI-MS/MS analysis revealed the presence of nine compounds were identified in E. astringens , which was characterized by a high content of gallic acid (542.4 ± 8.2 μg g ^-1 ), whereas E. mattosii contained eleven identified compounds, with epicatechin (533.2 ± 90.4 μg g ^-1 ) and catechin (359.8 ± 10.8 μg g ^-1 ) as major compounds. Gallic acid, protocatechuic acid, syringic acid, p -coumaric acid, scopoletin, p -anisic acid, abscisic acid, quercetin, and galangin were identified for the first time in E. astringens , while epicatechin, vanillic acid, and ferulic acid were reported for the first time in E. mattosii . The extracts exhibited activity against Gram-positive bacteria, with E. astringens showing the highest potency (MIC = 15.62 μg mL ^-1 against Staphylococcus aureus and MRSA; 7.81 μg mL ^-1 against Staphylococcus epidermidis ), whereas E. mattosii showed MIC values of 125 μg mL ^-1 against all strains. No relevant activity was observed against the Gram-negative bacteria tested. Active extracts and fractions inhibited biofilm formation at 7.81–15.62 μg mL ^-1 , while mature biofilm eradication was observed mainly against MRSA, with EBH ≥125 μg mL ^-1 and DCM ≥62.5 μg mL ^-1 . Growth kinetics confirmed sustained inhibition by selected fractions. Checkerboard assays revealed synergistic interactions between ampicillin and E. astringens against MRSA, (fractional inhibitory concentration index (FICI) = 0.24–0.28), and against S. epidermidis (FICI = 0.35–0.36). These findings are relevant because potentiation of ampicillin activity may enhance β-lactam efficacy against resistant Staphylococcus . SYTOX green assays demonstrated that the active samples, especially DCM from E. astringens and FAE from E. mattosii increased bacterial membrane permeability, suggesting membrane disruption as one of the mechanisms underlying their antibacterial activity. Cytotoxicity assays in RAW 264.7 macrophages demonstrated low toxicity at MIC concentrations. Collectively, the potent anti-staphylococcal activity, inhibition of biofilm formation, synergistic interactions with ampicillin, membrane permeabilization, and low cytotoxicity at MIC concentrations highlight E. astringens as a promising source of antibacterial compounds and antibiotic adjuvants. These findings support further investigation of E. astringens against resistant Gram-positive pathogens.

This study investigated the anti-inflammatory activity of the crude hydroalcoholic extract of Myrcia splendens leaves. In vitro, neutrophil chemotaxis and LPS-induced inflammatory mediators were assessed in neutrophils or macrophages treated with M. splendens, salicylic acid, or gallic acid. Inflammation resolution was evaluated via efferocytosis. In vivo effects were tested using the air pouch model. M. splendens impaired macrophage secretion of TNF, IL-1β, IL-6, and NO following LPS stimulation. Neutrophils treated with LPS and incubated with the extract showed reduced migration and NO secretion. Likewise, salicylic and gallic acids decreased NO production in LPS-stimulated neutrophils. The extract enhanced efferocytosis, increased IL-10, and decreased TNF levels. In vivo, similar effects were observed, including reduced neutrophil migration and NO production. These findings suggest that M. splendens modulates neutrophil and macrophage functions, likely due to the presence of salicylic and gallic acids. This highlights its potential as a treatment for inflammatory conditions.

The genus Myrcia from the Myrtaceae family contains species with therapeutic properties, such as reducing glycemia and oxidative stress. This study investigated the effects of the hydroalcoholic extract of Myrcia tijucensis in an animal model of Type 1 diabetes induced by alloxan. The objective was to evaluate its antidiabetic and antioxidant activities, as well as its effects on pancreatic islets. Chromatographic analysis by HPLC–MS/MS revealed, for the first time in the genus Myrcia , the presence of phenolic acids such as vanillic acid, syringic acid, vanillin, p ‐coumaric acid, and salicylic acid. The extract demonstrated potent inhibition of the α‐glucosidase enzyme (IC ₅₀ = 0.17 ± 0.01 mg/mL), suggesting a hypoglycemic mechanism. At the biological level, treatment with the extract significantly reduced oxidative stress, as evidenced by a decrease in thiobarbituric acid reactive substances (TBA‐RS) and normalization of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px). Additionally, an improvement in the architecture of pancreatic islets was observed, with an increase in islet diameter in treated groups, suggesting potential cellular regeneration. Altogether, the extract of M. tijucensis has proven promising for studies in adjunctive therapy for Type 1 diabetes, helping to control glycemia, reduce oxidative stress, and preserve pancreatic islets.

The aim of this study was to characterize the phytochemical profile and potential antiaging and wound‐healing activities of 70% hydroalcoholic crude extract (CHE) from Myrcia neoobscura leaves and its fractions—insoluble (IF), ethyl acetate (EAF), and aqueous (AF)—for use in phytocosmetics for skin application. CHE and its fractions showed high concentrations of total phenolics, including flavanols and flavonoids. Ten phenolic compounds were identified, with gallic acid as the major, followed by chlorogenic and p ‐coumaric acids. Catechin, isoorientin, taxifolin, resveratrol, naringenin, and eriodictyol were reported for the first time in the genus. CHE and AF showed the best results in antioxidant assays. In antiglycation activity, EAF showed the highest oxidative glycation inhibition, comparable to quercetin. CHE and AF exhibited the strongest collagenase and elastase inhibition. CHE, IF, and EAF showed the highest SPF. CHE promoted 81.86% fibroblast migration in 24 h, indicating strong wound‐healing potential. CHE maintained cellular viability in the MTT assay. In the HET‐CAM assay and agarose overlay assays, CHE and fractions were classified as non to mildly irritating. These results suggest potential antiaging applications, mainly attributed to the phenolic profile.

Myrcia genus plants, like Myrcia pubipetala, traditionally used as hypoglycemic agents, hold promise for Type 1 Diabetes Mellitus (DM1) research but need more comprehensive chemical and pharmacological investigation. This is an experimental study involving controlled administration of treatments to a group of rats to assess their effects compared with a control group, investigating the effects of M. pubipetala on alloxan-induced Type 1 Diabetes Mellitus in rats. After the induction of diabetes, the rats received the hydroalcoholic extract (HAE) or aqueous fraction (AF) (25, 50, 100, or 150 mg kg-1) of M. pubipetala, or water. The results showed that diabetic rats presented cell damage in kidneys, oxidative stress, and high levels of glucose and triglycerides in their plasma and erythrocytes. The HAE (150 mg kg-1), per se, reduced lipid and protein oxidation, and the AF (150 mg kg-1) decreased lipoperoxidation. AF (150 mg kg-1), per se, decreased triglyceride levels. Conclusion: treatment with HAE and AF reduced oxidative damage, positively modulated antioxidant defenses, and exerted hypoglycemic and hypolipidemic effects, representing a potential adjuvant treatment for diabetes.

Acca sellowiana é uma espécie nativa do planalto meridional brasileiro, cujo fruto é frequentemente alvo de estudos, pois apresenta efeitos terapêuticos em algumas condições, como na inflamação e na dor. O objetivo do estudo é avaliar efeitos do extrato hidroalcoólico dos frutos da Acca sellowiana frente a estímulos inflamatórios e dolorosos. Para tanto, utilizou-se do modelo da bolsa de ar no qual foi induzido um processo inflamatório no tecido subcutâneo de camundongos Swiss machos com carragenina, teste da formalina intra-plantar no qual os animais recebem injeção de formalina 2,5% na superfície ventral da pata posterior direita. Ainda, utilizou-se o teste do ácido acético, no qual injeta-se uma solução do ácido acético por via intraperitoneal, por fim a avaliação da toxicidade aguda com dose fixa através da análise bioquímica. O extrato apresentou significativa diminuição na migração de leucócitos, tanto no exsudato da bolsa de ar assim como no tecido. Além disso, o extrato demonstrou atividade antinociceptiva nos testes do ácido acético e da formalina. Ainda, foi observado que o extrato não apresentou indícios de toxicidade aguda. Portanto, conclui-se que o extrato possui atividade anti-inflamatória e antinociceptiva não apresentando indícios de toxicidade bioquímica.

Fibromyalgia (FM) is a painful chronic condition that significantly impacts the quality of life, posing challenges for clinical management. Given the difficulty of understanding the pathophysiology and finding new therapeutics, this study explored the effects of a medicinal plant, E. brasiliensis, in an FM model induced by reserpine in Swiss mice. Animals were treated with saline 0.9% (vehicle), duloxetine 10 mg/kg (positive control), or hydroalcoholic extract of E. brasiliensis leaves 300 mg/kg (HEEb). Nociceptive parameters, as well as locomotion, motor coordination, strength, anxiety, and depressive-like behaviors, were evaluated for 10 days. After that, the brain and blood were collected for further analysis of cytokines (interleukin 1? and interleukin 6), brain-derived neurotrophic factor (BDNF), and the immunocontents of total and phosphorylated Tropomyosin receptor kinase B (TrkB). The results demonstrated that the acute and prolonged treatment with HEEb was able to reduce both mechanical and thermal nociception. It was also possible to observe an increase in the strength, without changing locomotion and motor coordination parameters. Interestingly, treatment with HEEb reduces anxious and depressive-like behaviors. Finally, we observed a reduction in inflammatory cytokines in the hippocampus of animals treated with HEEb, while an increase in BDNF was observed in the prefrontal cortex (PFC). However, no alterations related to total and phosphorylated TrkB receptor expression were found. Our study demonstrated the antinociceptive and emotional effects of HEEb in mice, possibly acting on neuroinflammatory and neurotrophic mechanisms. These data provide initial evidence about the E. brasiliensis potential for treating chronic pain. Graphical Abstract

A depressão e a ansiedade são psicopatologias que afetam parcela significativa da população mundial, ainda assim, pesquisas mostram baixa adesão aos seus tratamentos. Assim, são de suma importância estudos que busquem melhorar e diversificar as abordagens terapêuticas desses transtornos. A fitoterapia, por sua vez, busca utilizar conhecimentos populares para complementar a atividade em saúde, sendo implementada como prática integrativa complementar no SUS desde 2006. No presente estudo, a planta estudada é a Acca sellowiana, família Myrtaceae, muito cultivada no clima subtropical, que contém componentes como flavonoides, taninos e terpenos. O objetivo deste trabalho é comparar o efeito do extrato do fruto da Acca sellowiana com tratamento convencional sobre os comportamentos tipo depressivo e tipo ansiogênico em camundongos Swiss machos. Como metodologia, a fim de avaliar os comportamentos ansioso e depressivo dos camundongos, foram utilizados os testes animais: labirinto em cruz elevada, teste caixa claro escuro, teste campo aberto, teste de esconder esferas; e teste de suspensão pela cauda e teste de nado forçado respectivamente. O extrato foi utilizado nas dosagens de 100 mg/kg e 800 mg/kg e administrado por via oral uma hora antes dos experimentos. Os resultados nos testes não demonstraram ação antidepressiva e ansiolítica com o uso do extrato de A. sellowiana. Portanto, demonstrou-se que este não tem efeito agudo, quando sob as condições utilizadas neste estudo, no tratamento das doenças em questão.