Systemic Inflammation Disrupts Circadian Rhythms and Diurnal Neuroimmune Dynamics.

Circadian rhythms regulate physiological processes in approximately 24 h cycles, and their disruption is associated with various diseases. Inflammation may perturb circadian rhythms, though these interactions remain unclear. This study examined whether systemic inflammation induced by an intraperitoneal injection of lipopolysaccharide (LPS) could alter central and peripheral circadian rhythms and diurnal neuroimmune dynamics. Mice were randomly assigned to two groups: the saline control group and the LPS group. The diurnal expression of circadian clock genes and inflammatory cytokines were measured in the hypothalamus, hippocampus, and liver. Diurnal dynamic behaviors of microglia were also assessed. Our results revealed that the LPS perturbed circadian gene oscillations in the hypothalamus, hippocampus, and liver. Furthermore, systemic inflammation induced by the LPS could trigger neuroinflammation and perturb the diurnal dynamic behavior of microglia in the hippocampus. These findings shed light on the intricate link between inflammation and circadian disruption, underscoring their significance in relation to neurodegenerative diseases.

Distribution of delta sleep-inducing peptide in the newborn and infant human hypothalamus: an immunohistochemical study

The distribution of delta sleep-inducing peptide immunoreactive cell bodies, fibers, and terminal-like structures was investigated in the normal human hypothalamus during the first postnatal year, using immunohistofluorescence and peroxidase anti-peroxidase techniques. Immunolabeled perikarya were relatively few and were mostly scattered through the anterior (preoptic) and mediobasal regions (infundibular nucleus) of the hypothalamus. DSIP-immunoreactive fibers and terminal-like fibers were observed throughout the entire rostrocaudal extent of the hypothalamus. They exhibit high densities in the preoptic region, the organum vasculosum of lamina terminalis, infundibular nucleus and median eminence. Moderate to low densities of DSIP-immunoreactive fibers were observed in the other hypothalamic structures, located in the anterior and mediobasal regions of hypothalamus, such as periventricular, paraventricular, suprachiasmatic, ventromedial, dorsomedial and parafornical nuclei. In the present study, the analysis of the immunohistochemical pattern of DSIP-immunoreactive neuronal elements in the human infant hypothalamus during the first postnatal year provided evidence of the presence of several differences. We have found qualitative age-related changes in the density of DSIP immunoreactivity in several hypothalamic structures such as the anterior region and the median eminence.

Valoración del eje hipófisis-hipotálamo-adrenal en pacientes con corticoterapia crónica a dosis supresivas / Evaluation of the hypotha lamus-pituitary-adrenal axis in patients with chronic corticotherapy in suppresive dosis

Se efectuó la curva de cortisol en 32 individuos sanos con edad promedio de 38.7 años, siendo la cifra matutina de las ocho horas de 10 mg/100ml o mayor. Posteriormente, se realizó el mismo estudio a 42 enfermos, edad promedio 41.4 años, que estaban bajo corticoterapia mayor de 10 mg diarios de prednisona durante as de tres meses en forma ininterrunpida y la cual se suspendió 48 h previas al estudio. Se encontró que 27 de ellos (64.2 por ciento) tenían cifras de cortisol matutino menores a las del grupo testigo y los enfermos de artritis reumatoide eran de los de enfermedad sistémica podría ser un factor más en la supresión del eje H-H-A de los pacientes bajo dosis mayor de 10 mg de prednisona en duración mayor de tres meses continuos