Creatine kinase and its isoenzymes in the serum and cerebrospinal fluid of healthy canines.

BACKGROUND: Creatine kinase (CK) exists as three isoenzymes (CK-MM, CK-MB, and CK-BB) that are predominantly expressed in specific tissues and can be detected in both the serum and cerebrospinal fluid (CSF). CSF CK has been relatively unstudied in veterinary medicine, although studies in human medicine have demonstrated that changes in total CSF CK activity can indicate neurologic abnormalities. OBJECTIVES: The purpose of this study was to establish reference intervals for CK and its three major isoenzymes in the serum and CSF of clinically healthy dogs. By establishing a definitive reference interval for this enzyme in healthy canines, the diagnostic use and possible significance of CK in clinical disease can be studied. METHODS: Serum and/or CSF were collected from healthy dogs. Total CK activity was measured spectrophotometrically, and isoenzyme distributions were determined using the QuickGel CK Vis Isoenzyme Kit and a densitometric scanner. Total CK and CK isoenzyme activities were determined within 8 h of collection. RESULTS: The median serum total CK in healthy canines was 159.0 U/L (range: 53.0-539.0 U/L), while the median CSF total CK was 3.7 U/L (range: 2.0-84.0 U/L). CK-BB and CK-MM were approximately equal in the serum, while CK-MM was the predominant isoenzyme in the CSF. CONCLUSIONS: Knowledge of the normal distribution and concentration of CK in canine serum and CSF will set the foundation for future studies of canine CK as a potentially clinically useful biomarker.

Brain-Type Creatine Kinase Release from Cultured Osteoclasts Exposed to Neridronate in Children Affected by Osteogenesis Imperfecta Type 1.

Brain-type creatine kinase (CK-BB) increases during osteoclastogenesis, with high circulating amounts in type I osteogenesis imperfecta (OI) following treatment with neridronate, a bisphosphonate able to inhibit osteoclast activity and survival. The aim of this study was to demonstrate the correlation between osteoclastogenesis and CK-BB release from OI patients' osteoclasts treated with different concentrations of neridronate. Our patients showed reduced bone quality, increased levels of CTX I, a marker of bone resorption, and decreased levels of OPG, an inhibitor of osteoclastogenesis. In OI patients, the presence of MCSF and RANKL determined an increased secretion of CK-BB from osteoclasts (p = 0.04) compared with control conditions without these cytokines; interestingly, in the absence of these factors, the secretion of CK-BB is significantly elevated at 3 µmol/L compared with 0.03 and 1 µmol/L (p = 0.007). In healthy donors' cultures, the higher concentration of CK-BB can be detected following stimulation with 3 µmol/L neridronate compared with the untreated condition both with and without MCSF and RANKL (p = 0.03 and p = 0.006, respectively). Consistently, in osteoclast cultures, neridronate treatment is associated with a decrease in multinucleated TRAP+ cells, together with morphology changes typical of apoptosis. Consistently, in the media of the same osteoclast cultures, we demonstrated a significant increase in caspase-3 levels. In conclusion, our findings support the idea that CK-BB levels increase in the serum of OI-treated patients.

Value of brain damage biomarkers in cerebrospinal fluid in neonates with hypoxic-ischemic brain injury.

Hypoxic-ischemic encephalopathy is one of the leading causes of death and neurological disability worldwide. A key issue in neonates with hypoxic-ischemic encephalopathy is accurately establishing the occurrence and severity of brain lesions soon after a perinatal hypoxic-ischemic event. This is crucial to help with prognosis; guide clinical decision-making, including the use of other therapies; and improve family counseling. Neurobiochemical markers may offer a quantitative approximation for estimating the severity of brain damage and identifying infants who have a high risk of further neurological disability. In addition, they should help identify those neonates who would benefit most from the implementation of other neuroprotective and neuroreparative interventions. Despite considerable progress in this area, relatively few studies have been aimed at examining the clinical utility of brain-specific proteins in cerebrospinal fluid, an important opening to characterizing pathological phenomena associated with hypoxic-ischemic brain injury.

Screening for Duchenne muscular dystrophy in Germany, 1977-2011: A personal story.

EDITOR'S NOTE: This article by Dr. Günter Scheuerbrandt is a fascinating personal account and historical narrative of the birth and development of a screening program for Duchenne Muscular Dystrophy in Germany, beginning 40 years ago. As the author notes, approval of an institutional review board or ethics committee was not required for this type of scientific investigation in one's field at the time this program was begun, but we have removed all personal data from any of the materials presented in here in order to conform to current concepts of ethical publication. This article is about the screening of 528,410, mostly 4-6-week-old, boys in Germany between 1977 and 2011 for high levels of creatine kinase (CK) to identify those with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). During these 34 years of infant screening, 147 boys with confirmed, probable, and possible DMD (incidence 1:3,600 male births) and 33 boys with confirmed, probable, and possible BMD (incidence 1:15,500 male births) were found. Research reports about DMD were sent to families and pediatricians participating in the screening, and, on request, to families and scientists everywhere. It is hoped that screening programs used as the basis for future therapies will be able to modify the natural history of boys with DMD. New dystrophin mutations will continue to occur, necessitating screening and early therapy. Abstract Submitted for Presentation at the 10th International Society for Neonatal Screening-Asia Pacific Regional Meeting, August 2017, Ulaanbataar, Mongolia. Muscle Nerve 57: 185-188, 2018.

Early predictors of brain damage in full-term newborns with hypoxic ischemic encephalopathy.

OBJECTIVE OF THE STUDY: To evaluate the value of serum creatine phosphokinase-brain specific (CK-BB) and urinary lactate/creatinine (L/C) ratio as early indicators of brain damage in full-term newborns with hypoxic ischemic encephalopathy (HIE). PATIENTS AND METHODS: A case-control study including 25 full-term new-born infants with perinatal asphyxia who were admitted to neonatal intensive care unit (NICU) with a proven diagnosis of HIE, compared to 20 healthy age- and sex-matched full-term newborns. All newborn infants were subjected to full history taking, clinical examination, routine investigations (cord blood gases and complete blood picture), and assessment of serum CK-BB (cord blood, 6 and 24 hours after birth) and urinary L/C ratio (collected within the first 6 hours, on the 2nd and 3rd day after birth). RESULTS: The serum CK-BB and urinary L/C ratio in infants with HIE were significantly higher in samples collected throughout the monitoring period when compared with the control group (all P<0.001). The cord CK-BB and urinary L/C ratio within the first 6 hours were significantly higher in infants with severe HIE than in infants with mild and moderate HIE (P<0.001). Cord CK-BB level at 12.5 U/L had 100% sensitivity and 84% specificity in the detection of severe HIE infants. Urinary L/C ratio of more than 10.5 collected within the first 6 hours after birth had 100% sensitivity and 78% specificity for the detection of severe HIE infants. CONCLUSION: The serum CK-BB and urinary L/C ratio in HIE infants were significantly increased early in the course of the disease, which can be used as useful indicators for predicting the development of HIE.

Plasma creatine kinase B correlates with injury severity and symptoms in professional boxers.

INTRODUCTION: Each year in the United States, approximately 1.7 million people sustain a traumatic brain injury (TBI). Of these TBI events, about 75 percent are characterized as being mild brain injuries. Immediately following TBI, a secondary brain damage persists for hours, days, and even months. Previously, detection of neuronal and glial biomarkers have proven to be useful to predict neurological outcomes. Here, we hypothesized that creatine kinase, brain (CKBB) is a sensitive biomarker for acute secondary brain injury in professional boxers. METHODS: Blood (8cc) was collected from the boxing athletes (n=18) prior to and after competition (∼30min). The plasma levels of CKBB were measured using the Meso Scale Diagnostic (MSD) electrochemiluminescence (ECL) array-based multiplex format. Additional data such as number of blows to the head and symptom score (Rivermead Post Concussion Symptoms Questionnaire) were collected. RESULTS: At approximately 30min after the competition, the plasma levels of CKBB were significantly elevated in concussed professional boxers and correlated with the number of blows to the head and symptom scores. Additionally, receiver operating curve (ROC) analysis yielded a 77.8% sensitivity and a specificity of 82.4% with an area under the curve (AUC) of 90% for CKBB as an identifier of secondary brain injury within this population. CONCLUSION: This study describes the detection of CKBB as a brain biomarker to detect secondary brain injury in professional athletes that have experienced multiple high impact blows to the head. This acute biomarker may prove useful in monitoring secondary brain injury after injury.

Serum creatine kinase isoenzymes and macroenzymes in dogs with different neurologic diseases.

BACKGROUND: Increased serum activity of CK isoenzymes and macroenzymes, and in particular of the brain isoenzyme (CK-BB) has been reported in dogs with central nervous system (CNS) disorders. However, no studies on the possible differences in serum activities of CK iso- or macroenzymes (Macro-CK1 and Macro-CK2) in different neurologic diseases are available. OBJECTIVE: The aim of this study was to describe the electrophoretic distribution of CK iso- and macroenzymes in dogs with CNS disorders in order to assess whether this distribution depends on a specific neurologic disease. METHODS: This study was done on sera from 45 dogs with neurologic diseases (degenerative, n = 7; idiopathic epilepsy [IE], n = 14; inflammatory, n = 16; space occupying lesions [SOL], n = 8) and from 10 clinically healthy dogs. The separation of serum CK isoenzymes and macroenzymes was performed using an automated electrophoretic method already validated in dogs. RESULTS: Compared with healthy dogs, dogs with CNS disorders had significantly higher total CK and CK-BB activities, and a significantly lower Macro-CK2 activity (P < .001). Comparison of pathologic subgroups and healthy dogs revealed significant differences (P < .01) in dogs with IE and inflammatory disorders for total CK activity, in all the subgroups for CK-BB (P < .01), and in dogs with IE and SOL for Macro-CK2 (P < .01). CONCLUSIONS: The results of this study suggest that CK-BB is released by neurons damaged by inflammatory or degenerative conditions or due to compressive effects of SOL. However, the neurologic diseases cannot be differentiated based on CK-BB or Macro-CK2 activities, unless further studies allow the definition of diagnostic thresholds.