Carvacrol attenuates lipopolysaccharide-induced testicular injury in rats through anti-apoptotic mechanisms

Carvacrol atenúa la lesión testicular inducida por lipopolisacárido en ratas a través de mecanismos antiapoptóticos

Background: Carvacrol, a bioactive compound derived from the herb Origanum vulgare, is recognized for its ability to reduce inflammation, oxidative stress, and prevent apoptosis. Lipopolysaccharide (LPS) is a potent trigger that initiates an inflammatory process, oxidative stress, and damage to germ cells within the testes. The purpose of this research was to explore the protective ability of carvacrol against LPS-induced testicular damage in rats. Methods: The study was conducted over a two-week period, during which 32 adult Wistar rats were randomly assigned to four groups: Control (saline), LPS (1 mg/kg/day), and C25 and C50 (receiving carvacrol (25 and 50 mg/kg/day) 30 min before LPS administration). Histopathology, sperm parameters and the expression of apoptosis-related genes were assessed. The results were analyzed with Statistical Package for Social Science (SPSS). Results: Findings revealed that LPS significantly decreased sperm (p < 0.001) and the normal sperm proportion (p = 0.02) relative to the Control. Carvacrol treatment notably increased sperm count (p < 0.001) and improved sperm morphology in both C25 (p = 0.006) and C50 (p < 0.001). Furthermore, Johnson’s score (p = 0.008 and p < 0.001), epithelial thickness (p = 0.002 and p < 0.001), and seminiferous tubule diameter (both p < 0.001) were significantly improved in C25 and C50 compared with LPS. Moreover, in C25 and C50, compared with LPS, carvacrol significantly reduced the gene expression of Bax (p = 0.01 and p = 0.02; in that order) and caspase-3 (both, p < 0.001). Conclusions: The findings indicate that carvacrol can effectively mitigate LPS-induced testicular dysfunction, potentially through its anti-apoptotic properties. These results highlight the therapeutic capacity of carvacrol in ameliorating testicular injury caused by various pathological conditions. However, additional studies are needed to verify its efficacy and safety in other models and to elucidate molecular pathways involved before carvacrol can be considered a therapeutic agent in clinical settings.

Resumen

Antecedentes: El carvacrol, un compuesto bioactivo derivado de la hierba Origanum vulgare, es reconocido por su capacidad para reducir la inflamación, defender contra el estrés oxidativo y prevenir la apoptosis. El lipopolisacárido (LPS) es un potente desencadenante que provoca procesos inflamatorios, carga oxidativa y daño a las células germinales dentro de los testículos. El objetivo de esta investigación fue explorar la capacidad protectora del carvacrol frente al daño testicular inducido por LPS en ratas. Métodos: El estudio se llevó a cabo durante un período de dos semanas, en el cual 32 ratas Wistar adultas fueron asignadas aleatoriamente a cuatro grupos: Control (solución salina), LPS (1 mg/kg/día) y C25 y C50 (que recibieron carvacrol (25 y 50 mg/kg/día) 30 minutos antes de la administración de LPS). Se evaluaron la histopatología, los parámetros espermáticos y la expresión de genes relacionados con la apoptosis. Los resultados fueron analizados con el programa Paquete estadístico para ciencias sociales (SPSS). Resultados: Los hallazgos revelaron que el LPS disminuyó significativamente el conteo espermático (p < 0.001) y la proporción de espermatozoides normales (p = 0.02) en comparación con el grupo control. El tratamiento con carvacrol aumentó notablemente el conteo espermático (p < 0.001) y mejoró la morfología espermática en ambos grupos C25 (p = 0.006) y C50 (p < 0.001). Además, la puntuación de Johnson (p = 0.008 y p < 0.001), el grosor epitelial (p = 0.002 y p < 0.001) y el diámetro de los túbulos seminíferos (ambos p < 0.001) mejoraron significativamente en C25 y C50 en comparación con el grupo LPS. Asimismo, en los grupos C25 y C50 respecto al LPS, el carvacrol redujo de manera significativa la expresión génica de Bax (p = 0.01 y p = 0.02, respectivamente) y caspasa-3 (ambos p < 0.001). Conclusiones: Los resultados indican que el carvacrol puede mitigar eficazmente la disfunción testicular inducida por LPS, posiblemente a través de sus propiedades anti-apoptóticas. Estos hallazgos destacan la capacidad terapéutica del carvacrol para mejorar las lesiones testiculares causadas por diversas condiciones patológicas. Sin embargo, se necesitan estudios adicionales para verificar su eficacia y seguridad en otros modelos y dilucidar las vías moleculares involucradas antes de que el carvacrol pueda considerarse un agente terapéutico en entornos clínicos.

Apoptosis; Carvacrol; Lipopolysaccharides; Sperm parameters; Testicular injuries

Palabras Clave

Apoptosis; Carvacrol; Lipopolisacáridos; Parámetros espermáticos; Lesiones testiculares

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