Does sleep deprivation and morphine influence wound healing?

Stress systems exacerbate the inflammatory response after corneal abrasion in sleep-deprived mice via the IL-17 signaling pathway

Sleep deprivation (SD) has a wide range of adverse health effects. However, the mechanisms by which SD influences corneal pathophysiology and its post-wound healing remain unclear. This study aimed to examine the basic physiological characteristics of the cornea in mice subjected to SD and determine the pathophysiological response to injury after corneal abrasion. Using a multi-platform water environment method as an SD model, we found that SD leads to disturbances of corneal proliferative, sensory, and immune homeostasis as well as excessive inflammatory response and delayed repair after corneal abrasion by inducing hyperactivation of the sympathetic nervous system and hypothalamic-pituitary-adrenal axis. Pathophysiological changes in the cornea mainly occurred through the activation of the IL-17 signaling pathway. Blocking both adrenergic and glucocorticoid synthesis and locally neutralizing IL-17A significantly improved corneal homeostasis and the excessive inflammatory response and delay in wound repair following corneal injury in SD-treated mice. These results indicate that optimal sleep quality is essential for the physiological homeostasis of the cornea and its well-established repair process after injury. Additionally, these observations provide potential therapeutic targets to ameliorate SD-induced delays in corneal wound repair by inhibiting or blocking the activation of the stress system and its associated IL-17 signaling pathway.

Insomnia Complaints and Perceived Immune Fitness in Young Adults with and without Self-Reported Impaired Wound Healing

Background and Objectives: Adequate sleep and an effective immune system are both essential to maintain a good health status. The current study aimed to determine the nature of insomnia complaints and perceived immune fitness among Dutch young adults with and without self-reported impaired wound healing. Materials and Methods: A total of (n = 2033) Dutch students (83.8% women) completed an online survey. Perceived immune fitness was assessed with a single-item scale and insomnia complaints with the SLEEP-50 insomnia subscale. The sample comprised a control group without self-reported impaired wound healing (n = 1622), a wound infection (WI) group (n = 69), a slow healing wounds (SHW) group (n = 250), and a COMBI group that experienced both WI and SHW (n = 92). Results: Comparisons with the control group revealed that individuals of the SHW and COMBI groups reported significantly poorer perceived immune functioning, increased insomnia complaints and daytime fatigue, and poorer sleep quality. Conclusions: Individuals with self-reported impaired wound healing have a poorer perceived immune functioning, increased insomnia complaints, daytime fatigue, and poorer sleep quality.

Innate Immunity Promotes Sleep through Epidermal Antimicrobial Peptides

Wounding and infection trigger a protective innate immune response that includes the production of antimicrobial peptides in the affected tissue as well as increased sleep. Little is known, however, how peripheral wounds or innate immunity signal to the nervous system to increase sleep. We found that, during C. elegans larval molting, an epidermal tolloid/bone morphogenic protein (BMP)-1-like protein called NAS-38 promotes sleep. NAS-38 is negatively regulated by its thrombospondin domain and acts through its astacin protease domain to activate p38 mitogen-activated protein (MAP)/PMK-1 kinase and transforming growth factor β (TGF-β)-SMAD/SMA-3-dependent innate immune pathways in the epidermis that cause STAT/STA-2 and SLC6 (solute carrier)/SNF-12-dependent expression of antimicrobial peptide (AMP) genes. We show that more than a dozen epidermal AMPs act as somnogens, signaling across tissues to promote sleep through the sleep-active RIS neuron. In the adult, epidermal injury activates innate immunity and turns up AMP production to trigger sleep, a process that requires epidermal growth factor receptor (EGFR) signaling that is known to promote sleep following cellular stress. We show for one AMP, neuropeptide-like protein (NLP)-29, that it acts through the neuropeptide receptor NPR-12 in locomotion-controlling neurons that are presynaptic to RIS and that depolarize this neuron to induce sleep. Sleep in turn increases the chance of surviving injury. Thus, we found a novel mechanism by which peripheral wounds signal to the nervous system to increase protective sleep. Such a cross-tissue somnogen-signaling function of AMPs might also boost sleep in other animals, including humans.

Microdialysis in postoperative monitoring of microvascular free flaps: Experiences with a decision algorithm

BACKGROUND

Reconstruction with free flaps has become a usual practice in maxillofacial surgery. Clinical monitoring is still the standard approach for postoperative follow-up, but can be difficult or impossible with intraorally situated or buried flaps. Microdialysis is a sampling technique that offers the possibility to monitor the metabolism of flaps continuously. It is a reliable method for early diagnosis of ischemia.

MATERIALS AND METHODS

48 microvascular free flaps applied following oral cancer resection were monitored with a microdialysis (MD) catheter, placed in the flap. Glucose, lactate, and lactate/pyruvate ratio were monitored using a bedside analyser for 5 days. 48 free flaps served as controls and were assessed (refill, flap temperature, and color) by clinical monitoring (CM).

RESULTS

12 flaps monitored by MD showed abnormal metabolism and underwent revision. Eight flaps were saved and four were lost within the first 5 days postoperatively. In addition, two flaps were lost at days 15 and 30 postoperatively, without previous complications. Four flaps assessed by CM developed complications, underwent revision, and were saved. In addition, five flaps were lost between the 8th and 23rd days postoperatively, without revision, due to missing previous clinical signs.

CONCLUSION

Postoperative monitoring of free flaps using a microdialysis decision algorithm allows early diagnosis of anastomotic complications. It is a clinically feasible and sensitive monitoring method for microvascular flaps, allowing surgical revision to be undertaken before clinical alteration takes place.

Associations between anxiolytic medications and ventral hernia repair

PURPOSE

This study examines the relationship between anxiolytic medications (AXM) on outcomes following ventral hernia repair.

METHODS

A single-center review of prospectively obtained perioperative and 30-day outcome data, including AXM use at admission, as part of the National Surgery Quality Improvement Program.

RESULTS

Sixty-three of the 393 patients who presented for ventral hernia repair were taking an AXM (15.6%). AXM users were more likely to have a higher ASA class, dyspnea, and treated hypertension (p < 0.05). AXM use was associated with increased operative duration, hernia size, increased estimated blood loss, and need for component separation. After adjusting for medical comorbidities, AXM users were not found to have greater 30-day morbidity or mortality. Patients taking AXM were found to have greater length of stay and increased hospital readmissions.

CONCLUSIONS

Patients taking anxiolytic medications undergoing ventral hernia repairs have higher ASA scores, more complex hernia characteristics, and require more concurrent procedures. They were found to have longer operative times, increased blood loss, greater duration of hospital stay, and increased readmissions that were associated with the increased perioperative risk factors. Further studies are required to determine causal links.

Morphine Induces Fibroblast Activation through Up-regulation of Connexin 43 Expression: Implication of Fibrosis in Wound Healing

Morphine is the most effective drugs for attenuating various types of severe pain, but morphine abuse carries a high risk of systemic fibrosis. Our previous have indicated that systemic administration of morphine hinders angiogenesis and delays wound healing. Here we have explained the pathological mechanism underlying the effect of morphine on wound healing. To determine how morphine affects wound healing, we first created a wound in mice treated them with a combination of a low doses (5 mg/kg/day) and high doses (20 or 30 mg/kg/day) of morphine. An In vivo study revealed that high-dose morphine-induced abnormal myofibroblasts persist after the end of wound healing because of connexin 43 (Cx43) upregulation. High-dose morphine-induced Cx43 increased the expression levels of focal adhesion molecules, namely fibronectin and alpha-smooth muscle actin (α-SMA) through the activation of transforming growth factor (TGF)-β1 signaling. In addition, we found that Cx43 contributed to TGF-βRII/ Smad2/3 signaling for regulating the differentiation of fibroblasts into myofibroblasts during high-dose morphine exposure. In conclusion, the abnormal regulation of Cx43 by morphine may induce systemic fibrosis because of abnormal myofibroblast function.

Decreased sleep duration: a risk of progression of degenerative lumbar scoliosis

Degenerative lumbar scoliosis (DLS) is a spinal deformity that develops after skeletal maturity with a Cobb angle of more than 10° in the coronal plane. As the life expectancy of our population increases, DLS becomes a prevalent health issue affecting the quality of life of the elderly. The degree of the scoliosis curvature affects not only the symptoms but also the choice of treatments. Osteoporosis and intervertebral disc degeneration (IDD) have been suggested as two important risks associated with the progression of DLS. Interestingly, recent data implicate interleukin-1 (IL-1) in the altered matrix biology that characterizes human IDD. Compelling evidence links decreased sleep duration to lower bone mineral density (BMD) and elevated expression of IL-1. Based on these evidences, we propose that decreased sleep duration might be a risk of the progression of DLS, and hypothesize that the underlying mechanisms might be the elevated excretion of glucocorticoids and elevated expression of IL-1.