Universidad Autonóma Metropolitana

The regenerative potential of mesenchymal stromal cells (MSCs) is linked to their secretion of bioactive molecules that modulate cellular processes. Different immunomodulatory molecules enhance their secretory and functional capacity. PACAP reduces oxidative stress and apoptosis, while promoting proliferation and cell differentiation. It also regulates inflammation and the immune response, but its role in MSCs secretoma modulation remains poorly explored. This study aimed to evaluate the effect of conditioned medium (CM) derived from PACAP -preconditioned MSCs on the recovery of β-pancreatic cells from the RINm5F line exposed to oxidative damage.

MSCs were obtained from adipose tissue of Sprague-Dawley rats. The concentration of PACAP to stimulate MSCs viability was determined by MTT assay. The mitochondrial metabolism of MSCs was significantly increased by PACAP at 0.1nM for 48 h. We evaluated the resulting CM protective effect in RINm5F cells exposed to oxidative damage by high glucose and streptozotocin (STZ). A dose-response curve was previously performed to select the CM concentration. Viability, mitochondrial membrane potential (MMP), radical oxygen species (ROS), apoptosis, glutathione peroxidase (GPx) activity and insulin secretion were all evaluated. RINm5F β-pancreatic cells treated with PACAP-preconditioned MSCs CM increased cells viability, restored MMP, reduced ROS and apoptosis caused by oxidative stress. In addition, we observed an increase in GPx antioxidant activity, and functional recovery of these cells was confirmed by increased insulin levels.

CM from PACAP-MSCs reverses oxidative damage and apoptosis of RINm5F-pancreatic B cells caused by high glucose and STZ, probably by stimulating their antioxidant response, without ruling out other compensatory mechanisms.

Pollen aeroallergens cause up to 40 % of respiratory allergies and are challenging to control due to their widespread distribution in the environment. The pollen of Ligustrum lucidum (privet) is a significant source of inhalant allergens. However, despite its clinical relevance, the protein composition of L. lucidum pollen remains poorly characterized. Therefore, we employed an integrated proteomic and transcriptomic approach to explore its potential allergen composition, focusing on possible cross-reactivity with Olea europea (olive), a well-studied allergenic relative. Using LC-MS/MS-based proteomics and RNA-seq transcriptomics, we detected 13 of the 15 known olive-like allergens, demonstrating high cross-species conservation. Proteomic analysis identified nine homologous allergens, including Ole e 1, Ole e 2, Ole e 3, Ole e 5, Ole e 6, Ole e 9, Ole e 12, Ole e 13, and Ole e 14. Transcriptomic analysis revealed four additional putative allergens: Ole e 8, Ole e 10, Ole e 11, and Ole e 15. These proteins shared 74-95 % sequence identity with their olive counterparts and exhibited multiple isoforms. Our findings provide a set of L. lucidum pollen potential allergens and highlight the utility of multi-omics in allergen discovery. However, further clinical validation of these putative novel allergens is needed to assess their role in sensitization and cross-reactivity. SIGNIFICANCE: Privet (Ligustrum), a genus within the Oleaceae family, is biologically significant due to its role in triggering allergic respiratory diseases worldwide. As a close relative of olive (Olea europaea) and ash (Fraxinus), privet shares allergenic proteins that contribute to cross-reactivity among sensitized individuals. Climate change has been shown to extend their flowering period, increasing pollen exposure and exacerbating allergic symptoms. Ligustrum is widely used in urban landscaping due to its rapid growth, resistance to pollution, and adaptability to diverse soil conditions, which facilitates its global spread across North America, Europe, Asia, and South America. Notably, L. lucidum is a major sensitizing agent in Mexico City, where 37 % of allergic patients react to its pollen. The first identified allergen, Lig v 1, shares homology with Ole e 1 and Fra e 1. At the same time, Lig v 2 (profilin) mirrors Ole e 2, highlighting the molecular basis for cross-reactivity within the Oleaceae family. Recent proteomic studies have uncovered additional allergens, including enolase, β-1,3-glucanase, and ATP synthase subunits, further elucidating privet's allergenic potential. The absence of genomic data for L. lucidum has hindered research; however, advances in transcriptomic and proteomic approaches have enabled the identification of 13 of 15 known olive-like allergens in privet pollen, paving the way for improved diagnostics and targeted therapies. This underscores the need for further investigation into Ligustrum's allergenic components, particularly as climate change and urbanization amplify its public health impact, as well as, the potential for improved diagnosis and targeted therapies.

In this work, the application of an upscaling methodol. to the thermal hydraulic model of an LFR is presented.The upscaling process is applied to local equations, where a rigorous math. process yields reactor-scale equations containing information from the pin scale, in addition to information on the properties of each phase.Two phases are considered: the fuel rods are the solid phase, and the lead coolant is the liquid phase.The upscaled thermal model is coupled with a neutron model, a simplified expression of the diffusion equation that considers reactivity feedback.The scaled thermal hydraulic model allows the entire core to be analyzed using only two heat transfer equations, which contain scaled coefficients for both phases.These were calculated at different lead velocities to understand their behavior under potential velocity changes.The core neutron parameters were calculated using the Serpent code, and the models and coupling were implemented in COMSOL Multiphysics.The results show that the neutron flux profiles, fuel and coolant temperatures behave as the reactor design values.