ABSTRACT
Several clinical and experimental studies have demonstrated gender dimorphism in immune and organ responsiveness and in the susceptibility to and morbidity from shock, trauma, and sepsis. In this respect, cell-mediated immune responses have been shown to be depressed in males following trauma-hemorrhage, whereas they were aintained/enhanced in proestrus females. Furthermore, sex hormones have been shown to be responsible for this gender-specific immune response following adverse circulatory conditions. More specifically, studies indicate that androgens produce immunodepression following trauma-hemorrhage in males. In contrast, female sex steroids appear to exhibit immunoprotective properties following trauma and severe blood loss. With regard to the underlying mechanisms, receptors for sex hormones have been identified on various immune cells suggesting direct effects of these hormones on the immune cells. Alternatively, indirect effects of sex hormones, ie, modulation of cardiovascular responses or androgen- and estrogen-synthesizing enzymes, might contribute to gender-specific immune responses. Recent studies indicate that sex hormones, eg, dehydroepiandrosterone (DHEA), also modulate the function of peripheral blood mononuclear cells in surgical patients. Thus, the immunomodulatory properties of sex hormones/receptor antagonists/sex steroid synthesizing enzymes following trauma-hemorrhage suggests novel therapeutic strategies for the treatment of immunodepression in surgical patients.
Subject(s)
Gonadal Steroid Hormones/immunology , Sepsis/immunology , Sex Factors , Shock, Hemorrhagic/immunology , Wounds and Injuries/immunology , Adjuvants, Immunologic/therapeutic use , Androgen Receptor Antagonists , Androgens/immunology , Blood Circulation , Dehydroepiandrosterone/immunology , Dehydroepiandrosterone/therapeutic use , Disease Susceptibility , Estrogens/immunology , Female , Humans , Immunocompetence , Male , Receptors, Androgen/immunology , Receptors, Androgen/therapeutic use , Receptors, Estrogen/immunology , Sepsis/drug therapy , Sepsis/physiopathology , Shock, Hemorrhagic/drug therapy , Shock, Hemorrhagic/physiopathology , Trauma Severity Indices , Wounds and Injuries/drug therapy , Wounds and Injuries/physiopathologyABSTRACT
Several clinical and experimental studies have demonstrated gender dimorphism in immune and organ responsiveness and in the susceptibility to and morbidity from shock, trauma, and sepsis. In this respect, cell-mediated immune responses have been shown to be depressed in males following trauma-hemorrhage, whereas they were aintained/enhanced in proestrus females. Furthermore, sex hormones have been shown to be responsible for this gender-specific immune response following adverse circulatory conditions. More specifically, studies indicate that androgens produce immunodepression following trauma-hemorrhage in males. In contrast, female sex steroids appear to exhibit immunoprotective properties following trauma and severe blood loss. With regard to the underlying mechanisms, receptors for sex hormones have been identified on various immune cells suggesting direct effects of these hormones on the immune cells. Alternatively, indirect effects of sex hormones, ie, modulation of cardiovascular responses or androgen- and estrogen-synthesizing enzymes, might contribute to gender-specific immune responses. Recent studies indicate that sex hormones, eg, dehydroepiandrosterone (DHEA), also modulate the function of peripheral blood mononuclear cells in surgical patients. Thus, the immunomodulatory properties of sex hormones/receptor antagonists/sex steroid synthesizing enzymes following trauma-hemorrhage suggests novel therapeutic strategies for the treatment of immunodepression in surgical patients.
Uma série de estudos clínicos e experimentais demonstram a existência de dimorfismo sexual das respostas imunológicas e orgânicas, bem como da suscetibilidade e morbidade em relação ao choque, ao trauma e à sepse. Respostas imunes celularmente mediadas apresentam-se deprimidas em machos em resposta ao binômio trauma-hemorragia, mas conservados/enaltecidos em fêmeas em proestro. Adicionalmente demonstra-se que os hormônios sexuais são responsáveis por esta dicomotomia de resposta sexualmente específica, em condições cardiovasculares adversas. Estudos específicos indicam que os andrógenos produzem imunodepressão pós-trauma hemorragia em machos. Em contraste, esteróides sexuais femininos parecem exibir propriedades imunoprotetoras após episódios de trauma com ou sem perda importante de sangue. No terreno dos mecanismos subjacentes, foram identificados receptores para hormônios sexuais em várias células do sistema imunológico, sugerindo a existência de efeitos diretos destes hormônios sobre tais células. Alternativamente, observam efeitos indiretos de hormônios sexuais tais como modulação das respostas cardiovasculares das enzimas sintetizadores de andrógeno e estrógeno, que podem contribuir para as estas respostas sexualmente diferenciadas. Estudos recentes indicam que os hormônios sexuais, como por exemplo a dehidroepiandrosterona também modulam a função de células mononucleares da série branca em pacientes cirúrgicos. Assim, as propriedades imunomodulatórias de hormônios sexuais/antagonistas de receptores/enzimas sintetizadores de esteróides após a ocorrência de trauma ou de hemorragia sugerem o caminho para novas estratégias terapêuticas para o tratamento de imunodepressão em pacientes cirúrgicos.