We have previously shown that some synthetic hydroxylated stigmastanes derived from plant sterols inhibit in vitro HSV-1 replication in ocular cell lines and decrease cytokine production in stimulated macrophages, suggesting that these steroids might combine antiviral and immunomodulating properties. In this paper we report the synthesis of some analogs fluorinated at C-6 in order to study the effect of this modification on bioactivity. The following methods were used: organic synthesis of fluorinated analogs, cytotoxicity determination with MTT assays, cytokine production quantification with ELISAs, glucocorticoid activity determination by displacement assays, immunofluorescence and transcriptional activity assays, studies of the activation of signaling pathways by Western blot, antiviral activity evaluation through virus yield reduction assays. We report the chemical synthesis of new fluorinated stigmastanes and show that this family of steroidal compounds exerts its immunomodulating activity by inhibiting ERK and Akt signaling pathways, but do not act as glucocorticoids. We also demonstrate that fluorination enhances the antiviral activity. Fluorination on C-6 did not enhance the anti-inflammatory effect, however, an increase in the in vitro antiviral activity was observed. Thus, our results suggest that it is possible to introduce chemical modifications on the parent steroids in order to selectively modulate one of the effects. This family of steroids could allow the development of an alternative treatment for ocular immunopathologies triggered by HSV-1, without the undesirable side effects of the currently used drugs.

HRSV is responsible for many acute lower airway infections and hospitalizations in infants, the elderly and those with weakened immune systems around the world. The strong inflammatory response that mediates viral clearance contributes to pathogenesis, and is positively correlated with disease severity. There is no specific effective therapy on hand. Antiviral synthetic stigmastanes (22S, 23S)-22,23-dihydroxystigmast-4-en-3-one (Compound 1) and 22,23-dihydroxystigmasta-1,4-dien-3-one (Compound 2) have shown to be active inhibiting unrelated virus like Herpes Simplex type 1 virus (HSV-1) and Adenovirus, without cytotoxicity. We have also shown that Compound 1 modulates the activation of cell signaling pathways and cytokine secretion in infected epithelial cells as well as in inflammatory cells activated by nonviral stimuli. In the present work, we investigated the inhibitory effect of both compounds on HRSV replication and their modulatory effect on infected epithelial and inflammatory cells. We show that compounds 1 and 2 inhibit in vitro HRSV replication and propagation and reduce cytokine secretion triggered by HRSV infection in epithelial and inflammatory cells. The compounds reduce viral loads and inflammatory infiltration in the lungs of mice infected with HRSV.

La membrana amniótica humana (hAM), derivada de la placenta, se ha consolidado como un biomaterial de alto valor terapéutico en medicina regenerativa gracias a sus propiedades antiinflamatorias, inmunomoduladoras, antimicrobianas y regenerativas. Su estructura avascular, su contenido de factores bioactivos (citoquinas, factores de crecimiento, inhibidores de metaloproteinasas) y su matriz extracelular rica en colágeno y laminina, la convierten en un sustrato ideal para promover la cicatrización, reducir la inflamación y actuar como barrera biológica en múltiples contextos clínicos. Este trabajo presenta un estado del arte actualizado sobre los usos médicos de la hAM en Argentina, describiendo sus mecanismos de acción, aplicaciones clínicas, formas de presentación y estado regulatorio. Se detallan sus efectos inmunomoduladores, mediados por células amnióticas epiteliales y mesenquimales, su papel en la reepitelización y angiogénesis, así como su potencial anticancerígeno basado en la secreción de factores como la trombospondina, endostatina e interleuquina 10. Asimismo, se destacan sus capacidades como soporte estructural y su utilidad en la ingeniería de tejidos. En la práctica clínica, la hAM se aplica en especialidades como oftalmología, dermatología, traumatología, cirugía plástica, ginecología y odontología. En oftalmología, por ejemplo, se utiliza para tratar úlceras corneales, defectos epiteliales persistentes y patologías inflamatorias de la superficie ocular. En dermatología y cirugía plástica se emplea para el tratamiento de úlceras crónicas, quemaduras y heridas quirúrgicas complejas. Su aplicación en ortopedia y odontología incluye la regeneración ósea y la prevención de adherencias. En Argentina, existen siete bancos de tejidos habilitados para procesar y distribuir hAM en diferentes formatos (criopreservada, liofilizada, desecada). Destacan instituciones como el Hospital Garrahan, el Laboratorio de Hemoderivados (UNC), el Banco Multitejidos Ecodaic (Córdoba) y Amnios BMA (Buenos Aires), que han desarrollado protocolos estandarizados para su obtención, procesamiento y distribución. Además, se presentan experiencias de investigación traslacional y aplicada en colaboración con CONICET, universidades y hospitales públicos. A pesar del crecimiento en su uso y producción, persisten desafíos regulatorios, logísticos y de concientización sobre la donación placentaria. No obstante, la hAM se perfila como un recurso estratégico con enorme potencial en salud pública, capaz de mejorar significativamente la calidad de vida de pacientes mediante terapias regenerativas accesibles y seguras.

This study evaluated the effects of two therapeutic approaches using a Bovine Collagen Matrix (BCM) and an innovative Amniotic Membrane Dressing (hAM-pe) in wound healing, integrating both clinical and mechanistic perspectives. Both treatments are collagen-based biomaterials, which play a crucial role in modulating the wound mi-croenvironment, supporting cellular adhesion, and delivering bioactive molecules. While collagen-based therapies have been extensively studied in vitro and in small animal models, clinical translation remains limited. This study’s approach involved the simul-taneous application of both treatments within a single patient, allowing a direct com-parison of therapeutic outcomes. Clinically, hAM-pe demonstrated superior outcomes, accelerating wound closure, re-ducing inflammation, and eliminating the need for surgical intervention. Its practical advantages, including ease of application in outpatient settings, further enhance its translational potential. Mechanistically, hAM-pe treatment was associated with reduced expression of inflammatory markers (IL-1β, TNF-α, and CXCL-10), enhanced vascular-ization (VEGF, CD34), and a shift toward a regenerative macrophage phenotype (Ar-ginase-1 expression). Conversely, BCM treatment led to prolonged inflammation, de-layed tissue remodeling, and an adverse granulomatous response. These findings underscore the potential of hAM-pe as an alternative, non-invasive therapy for chronic wounds. Further investigations into its immunoregulatory mecha-nisms, particularly its influence on macrophage subsets and extracellular matrix re-modeling, will provide valuable insights for optimizing regenerative wound care strategies.

Airborne particulate matter (PM₂.₅) contributes to oxidative damage of the ocular surface, particularly under dry eye-related hyperosmolar conditions. We evaluated the protective effects of a soluble extract derived from lyophilized human amniotic membrane patches (hAM-Te) in human corneal and conjunctival epithelial cells and THP-1 macrophages exposed to hyperosmolarity, industrial PM₂.₅, or both. Cell viability, migration, reactive oxygen species, nitrite production, total antioxidant capacity, and antioxidant enzyme activities were assessed. Combined hyperosmolarity and PM₂.₅ markedly impaired cell viability and migration while increasing oxidative and nitrosative stress. hAM-Te significantly improved cell viability and wound closure, reduced reactive oxygen species and nitrite levels, restored antioxidant capacity, and modulated endogenous antioxidant defenses. These findings demonstrate that hAM-Te attenuates redox imbalance and cellular injury induced by combined environmental and hyperosmolar stress, supporting its potential as a protective strategy against pollution-associated ocular surface damage.