Combinatory Effect of Pequi Oil (Caryocar brasiliense)-Based Nanoemulsions Associated to Docetaxel and Anacardic Acid (Anacardium occidentale) in Triple-Negative Breast Cancer Cells In Vitro.

Combination therapy integrated with nanotechnology offers a promising alternative for breast cancer treatment. The inclusion of pequi oil, anacardic acid (AA), and docetaxel (DTX) in a nanoemulsion can amplify the antitumor effects of each molecule while reducing adverse effects. Therefore, the study aims to develop pequi oil-based nanoemulsions (PeNE) containing DTX (PDTX) or AA (PAA) and to evaluate their cytotoxicity against triple-negative breast cancer cells (4T1) in vitro. The PeNE without and with AA (PAA) and DTX (PDTX) were prepared by sonication and characterized by ZetaSizer® and electronic transmission microscopy. Viability testing and combination index (CI) were determined by MTT and Chou-Talalay methods, respectively. Flow cytometry was employed to investigate the effects of the formulations on cell structures. PeNE, PDTX, and PAA showed hydrodynamic diameter < 200 nm and a polydispersity index (PdI) of 0.3. The association PDTX + PAA induced a greater decrease in cell viability (~70%, p < 0.0001) and additive effect (CI < 1). In parallel, an association of the DTX + AA molecules led to antagonism (CI > 1). Additionally, PDTX + PAA induced an expressive morphological change, a major change in lysosome membrane permeation and mitochondria membrane permeation, cell cycle blockage in G2/M, and phosphatidylserine exposure. The study highlights the successful use of pequi oil nanoemulsions as delivery systems for DTX and AA, which enhances their antitumor effects against breast cancer cells. This nanotechnological approach shows significant potential for the treatment of triple-negative breast cancer.

Persistent, new-onset symptoms and mental health complaints in Long COVID in a Brazilian cohort of non-hospitalized patients.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections lead to acute- and chronic Long COVID (LC) symptoms. However, few studies have addressed LC sequelae on brain functions. This study was aimed to examine if acute symptoms of coronavirus disease 2019 (COVID-19) would persist during LC, and if memory problems would be correlated with sleep, depressive mood, or anxious complaints. METHODS: Our work followed a cohort of 236 patients from two public hospitals of the Federal District in mid-western Brazil. Patients' interviews checked for clinical symptoms during acute and LC (5-8 months after real-time reverse transcription polymerase chain reaction, RT-qPCR). RESULTS: Most cases were non-hospitalized individuals (86.3%) with a median age of 41.2 years. While myalgia (50%), hyposmia (48.3%), and dysgeusia (45.8%) were prevalent symptoms in acute phase, fatigue (21.6%) followed by headache (19.1%) and myalgia (16.1%) commonly occurred during LC. In LC, 39.8% of individuals reported memory complaints, 36.9% felt anxious, 44.9% felt depressed, and 45.8% had sleep problems. Furthermore, memory complaints were associated with sleep problems (adjusted OR 3.206; 95% CI 1.723-6.030) and depressive feelings (adjusted OR 3.981; 95% CI 2.068-7.815). CONCLUSIONS: The SARS-CoV-2 infection leads to persistent symptoms during LC, in which memory problems may be associated with sleep and depressive complaints.

Docetaxel-loaded solid lipid nanoparticles prevent tumor growth and lung metastasis of 4T1 murine mammary carcinoma cells.

BACKGROUND: Metastasis causes the most breast cancer-related deaths in women. Here, we investigated the antitumor effect of solid lipid nanoparticles (SLN-DTX) when used in the treatment of metastatic breast tumors using 4T1-bearing BALB/c mice. RESULTS: Solid lipid nanoparticles (SLNs) were produced using the high-energy method. Compritol 888 ATO was selected as the lipid matrix, and Pluronic F127 and Span 80 as the surfactants to stabilize nanoparticle dispersion. The particles had high stability for at least 120 days. The SLNs' dispersion size was 128 nm, their polydispersity index (PDI) was 0.2, and they showed a negative zeta potential. SLNs had high docetaxel (DTX) entrapment efficiency (86%), 2% of drug loading and showed a controlled drug-release profile. The half-maximal inhibitory concentration (IC50) of SLN-DTX against 4T1 cells was more than 100 times lower than that of free DTX after 24 h treatment. In the cellular uptake test, SLN-DTX was taken into the cells significantly more than free DTX. The accumulation in the G2-M phase was significantly higher in cells treated with SLN-DTX (73.7%) than in cells treated with free DTX (23.0%), which induced subsequent apoptosis. TEM analysis revealed that SLN-DTX internalization is mediated by endocytosis, and fluorescence microscopy showed DTX induced microtubule damage. In vivo studies showed that SLN-DTX compared to free docetaxel exhibited higher antitumor efficacy by reducing tumor volume (p < 0.0001) and also prevented spontaneous lung metastasis in 4T1 tumor-bearing mice. Histological studies of lungs confirmed that treatment with SLN-DTX was able to prevent tumor. IL-6 serum levels, ki-67 and BCL-2 expression were analyzed and showed a remarkably strong reduction when used in a combined treatment. CONCLUSIONS: These results indicate that DTX-loaded SLNs may be a promising carrier to treat breast cancer and in metastasis prevention.