Analysis of difference in body fluid composition and dietary intake between Korean adults with and without type 2 diabetes mellitus / 한국영양학회지

Purpose@#Diabetes mellitus (DM) causes body fluid imbalance because of hyperglycemia, but there is a lack of research on the relationship between DM and body fluid imbalance in the Korean population. This study compared the differences in body fluid composition and dietary intake between individuals with type 2 DM (T2DM) and a normal control (NC) group without the disease. @*Methods@#In this study, 36 subjects with T2DM and 21 without diabetes were divided into the T2DM and NC groups. The subjects were divided into four subgroups to assess differences in body fluid volume according to sex: men T2DM group (n = 24), men NC group (n = 9), women T2DM group (n = 12), and women NC group (n = 12). The body fluid composition was measured using bioelectrical impedance analysis, including intracellular water (ICW), extracellular water (ECW), total body water (TBW), ECW/ICW, and ECW/TBW. Nutrient intake was evaluated using their dietary records. @*Results@#The results showed that the ECW/ICW and the ECW/TBW were significantly higher in the T2DM group compared to the NC group. Both men and women in the T2DM group showed significantly higher ECW/ICW and ECW/TBW than the respective NC group. The T2DM group had a higher carbohydrate, dietary fiber, vitamin A, vitamin C, sodium, and potassium intake per 1,000 kcal and lower total daily energy, fat, and cholesterol intake per 1,000 kcal than the NC group. @*Conclusion@#These results suggest a positive association between T2DM and body fluid imbalance. This study can be used widely as basic data for the evaluation and diagnosis of diabetic complications in the future.

XperCT-guided Intra-cisterna Magna Injection of Streptozotocin for Establishing an Alzheimer’s Disease Model Using the Cynomolgus Monkey (Macaca fascicularis)

Till date, researchers have been developing animal models of Alzheimer’s disease (AD) in various species to understand the pathological characterization and molecular mechanistic pathways associated with this condition in humans to identify potential therapeutic treatments. A widely recognized AD model that mimics the pathology of human AD involves the intracerebroventricular (ICV) injection with streptozotocin (STZ).However, ICV injection as an invasive approach has several limitations related to complicated surgical procedures. Therefore, in the present study, we created a customized stereotaxic frame using the XperCT-guided system for injecting STZ in cynomolgus monkeys, aiming to establish an AD model. The anatomical structures surrounding the cisterna magna (CM) were confirmed using CT/MRI fusion images of monkey brain with XperCT, the c-arm cone beam computed tomography. XperCT was used to determine the appropriate direction in which the needle tip should be inserted within the CM region. Cerebrospinal fluid (CSF) was collected to confirm the accurate target site when STZ was injected into the CM.Cynomolgus monkeys were administered STZ dissolved in artificial CSF once every week for 4 weeks via intracisterna magna (ICM) injection using XperCT-guided stereotactic system. The molecular mechanisms underlying the progression of STZ-induced AD pathology were analyzed two weeks after the final injection. The monkeys subjected to XperCT-based STZ injection via the ICM route showed features of AD pathology, including markedly enhanced neuronal loss, synaptic impairment, and tau phosphorylation in the hippocampus. These findings suggest a new approach for the construction of neurodegenerative disease models and development of therapeutic strategies.

Impaired Hand Dexterity Function in a Non-human Primate Model with Chronic Parkinson’s Disease

ymptoms of Parkinson’s disease (PD) caused by loss of dopaminergic neurons are accompanied by movement disorders, including tremors, rigidity, bradykinesia, and akinesia. Non-human primate (NHP) models with PD play an essential role in the analysis of PD pathophysiology and behavior symptoms. As impairments of hand dexterity function can affect activities of daily living in patients with PD, research on hand dexterity function in NHP models with chronic PD is essential. Traditional rating scales previously used in the evaluation of animal spontaneous behavior were insufficient due to factors related to subjectivity and passivity. Thus, experimentally designed applications for an appropriate apparatus are necessary. In this study, we aimed to longitudinally assess hand dexterity function using hand dexterity task (HDT) in NHP-PD models. To validate this assessment, we analyzed the alteration in Parkinsonian tremor signs and the functionality of presynaptic dopaminergic neuron using positron emission tomography imaging of dopamine transporters in these models. In addition, a significant inverse correlation between HDT and DAT level was identified, but no local bias was found. The correlation with intention tremor signs was lower than the resting tremor. In conclusion, the evaluation of HDT may reflect behavioral symptoms of NHP-PD models. Furthermore, HDT was effectively used to experimentally distinguish intention tremors from other tremors.

Assessment of Hand Motor Function in a Non-human Primate Model of Ischemic Stroke

Ischemic stroke results from arterial occlusion and can cause irreversible brain injury. A non-human primate (NHP) model of ischemic stroke was previously developed to investigate its pathophysiology and for efficacy testing of therapeutic candidates; however, fine motor impairment remains to be well-characterized. We evaluated hand motor function in a cynomolgus monkey model of ischemic stroke. Endovascular transient middle cerebral artery occlusion (MCAO) with an angiographic microcatheter induced cerebral infarction. In vivo magnetic resonance imaging mapped and measured the ischemia-induced infarct lesion. In vivo diffusion tensor imaging (DTI) of the stroke lesion to assess the neuroplastic changes and fiber tractography demonstrated three-dimensional patterns in the corticospinal tract 12 weeks after MCAO. The hand dexterity task (HDT) was used to evaluate fine motor movement of upper extremity digits. The HDT was modified for a home cage-based training system, instead of conventional chair restraint training. The lesion was localized in the middle cerebral artery territory, including the sensorimotor cortex. Maximum infarct volume was exhibited over the first week after MCAO, which progressively inhibited ischemic core expansion, manifested by enhanced functional recovery of the affected hand over 12 weeks after MCAO. The total performance time decreased with increasing success rate for both hands on the HDT. Compensatory strategies and retrieval failure improved in the chronic phase after stroke. Our findings demonstrate the recovery of fine motor skill after stroke, and outline the behavioral characteristics and features of functional disorder of NHP stroke model, providing a basis for assessing hand motor function after stroke.