Integrated analysis of RNA-seq datasets reveals novel targets and regulators of COVID-19 severity.

During the COVID-19 pandemic, RNA-seq datasets were produced to investigate the virus-host relationship. However, much of these data remains underexplored. To improve the search for molecular targets and biomarkers, we performed an integrated analysis of multiple RNA-seq datasets, expanding the cohort and including patients from different countries, encompassing severe and mild COVID-19 patients. Our analysis revealed that severe COVID-19 patients exhibit overexpression of genes coding for proteins of extracellular exosomes, endomembrane system, and neutrophil granules (e.g., S100A9, LY96, and RAB1B), which may play an essential role in the cellular response to infection. Concurrently, these patients exhibit down-regulation of genes encoding components of the T cell receptor complex and nucleolus, including TP53, IL2RB, and NCL Finally, SPI1 may emerge as a central transcriptional factor associated with the up-regulated genes, whereas TP53, MYC, and MAX were associated with the down-regulated genes during COVID-19. This study identified targets and transcriptional factors, lighting on the molecular pathophysiology of syndrome coronavirus 2 infection.

Survival during long-term storage, membrane integrity, and ultrastructural aspects of Lactobacillus acidophilus 05 and Lacticaseibacillus casei 01 freeze-dried with freshwater microalgae biomasses.

This study aimed to assess Spirulina platensis, Chlorella vulgaris, Scenedesmus quadricauda, and Lagerheimia longiseta microalgae potential as protective agents for probiotic cultures [(Lactobacillus acidophilus (La-05) and Lacticaseibacillus casei (Lc-01)] during freeze-drying, refrigeration storage (4 °C, 120 days), and in vitro simulated gastrointestinal conditions (SGIC). The occurrence of membrane damage and ultrastructural aspects of the cells were also verified. Fructooligosaccharides (FOS) were used as a positive control and saline solution as a negative control. The effects of the cryoprotectants on probiotic survival depended on the tested probiotic culture and microalgae biomass. For La-05, all tested cryoprotectants caused a lower reduction in probiotic counts during the freeze-drying and up to 90 days of storage. S. platensis kept higher probiotic counts during storage, while C. vulgaris protected the probiotic against the SGIC. L. longiseta decreased the probiotic membrane damage, mainly due to the production of exopolysaccharides, which was observed in the scanning electron microscopy (SEM). For Lc-01, all tested cryoprotectants promoted a lower reduction in probiotic counts up to 120 days of storage. FOS and S. quadricauda protected the probiotics during freeze-drying and refrigeration storage, while C. vulgaris protected the probiotic against the SGIC and caused lower membrane damage, mainly due to physical protection observed in SEM. In conclusion, microalgae biomasses exerted similar or better cryoprotectant effects on probiotics than FOS, a recognized cryoprotective agent.

Exploiting the use of agro-industrial residues from fruit and vegetables as alternative microalgae culture medium.

There is a need for searching new microalgae species, and the most suitable strategy to increase the cost-effectiveness of a microalgae culture system is to use resources of low costs, such as residues. This study aimed to evaluate the cultivation of microalgae isolated from the Brazilian Northeast region (Lagerheimia longiseta, Monoraphidium contortum, and Scenedesmus quadricauda) in an alternative medium of low cost (biocompost of discarded fruits and vegetables) with a view to possible applications in the food industry. Microalgae cultivated in the conventional synthetic medium was used as control. The cultivation of microalgae in the alternative medium allowed suitable cell growth, and improved the antioxidant activity and the levels of monounsaturated fatty acid and polyunsaturated fatty acid compared to the synthetic medium. The cultivation of S. quadricauda and L. longiseta species in the alternative medium resulted in increased protein content and/or total phenolic content, and improved health indices (lower levels of atherogenic, thrombogenic, and hypercholesterolemic saturated fatty acids indices, and higher levels of desired fatty acids index) compared to cultivation in synthetic medium. The cultivation of M. contortum in the alternative medium contributed to the production of higher lipid content, mainly saturated fatty acid (palmitic acid), which contributed negatively to the health indices. This study proved that S. quadricauda and L. longiseta microalga species from freshwaters have significant potential for distinct applications in functional food industries, and the biocompost of discarded fruits and vegetables is a suitable medium for microalgae cultivation.