Alzheimer's disease (AD) is characterized by the accumulation of amyloid beta (Aβ) and the hyperphosphorylation of tau protein in the brain, leading to the increase in inflammation and neuronal loss. Recently, evidences to support the association between type 2 diabetes mellitus (T2DM) and AD have markedly increased by clinical researches and experimental studies. Reduced insulin action and impaired glucose metabolism in the brain leads to diabetes induced AD. Androgen, a male sex hormone, was known to regulate inflammatory response, Aβ deposition in AD, insulin signaling, and synaptic plasticity in brain. Clinical studies demonstrated that androgen deficiency results in the increased risk of AD and its severe progression in male subjects. We reviewed the significant evidences to support that low testosterone levels are linked to diabetes-induced AD based on previous studies. Thus, we highlight the therapeutic potential of androgen in diabetes induced AD.
Alzheimer Disease* ; Amyloid ; Brain ; Diabetes Mellitus, Type 2 ; Glucose ; Humans ; Inflammation ; Insulin ; Insulin Resistance ; Male ; Metabolism ; Neuronal Plasticity ; Neurons ; tau Proteins ; Testosterone

Lipocalin-2 (LCN2), a secreted glycoprotein belonging to the lipocalin superfamily was reported to participate in various biological processes including cell migration, cell survival, inflammatory responses, and insulin sensitivity. LCN2 is expressed in the multiple tissues such as kidney, liver, uterus, and bone marrow. The receptors for LCN2 were additionally found in microglia, astrocytes, epithelial cells, and neurons, but the role of LCN2 in the central nervous system (CNS) has not been fully understood yet. Recently, in vitro, in vivo, and clinical studies reported the association between LCN2 and the risk of Alzheimer's disease (AD). Here, we reviewed the significant evidences showing that LCN2 contributes to the onset and progression of AD. It may suggest that the manipulation of LCN2 in the CNS would be a crucial target for regulation of the pathogenesis and risk of AD.
Alzheimer Disease ; Astrocytes ; Biological Processes ; Bone Marrow ; Brain ; Cell Movement ; Cell Survival ; Central Nervous System ; Diagnosis ; Epithelial Cells ; Glycoproteins ; In Vitro Techniques ; Inflammation ; Insulin Resistance ; Kidney ; Lipocalins ; Liver ; Microglia ; Neurons ; Prognosis ; Uterus

Research articles were reviewed to validate the estimated energy requirements (EERs) equations developed by the Institute of Medicine of the National Academies (IOM). These equations are based on total energy expenditure (TEE) measured by the doubly labeled water (DLW) method. We subsequently aimed to provide the basis for the suitability to apply the IOM equations as EER equations for Koreans, and develop relevant equations for EER in the Dietary Reference Intake for Koreans (KDRI). Additionally, besides the EER(IOM) equations, other equations were examined for EER estimation. Research papers demonstrating the validation of the EER(IOM) equations based on TEE(DLW) were searched through PubMed (up to September 2019). Of the 637 potentially relevant articles identified, duplicates and unsuitable titles and abstracts were excluded. Furthermore, papers with irrelevant subject and inappropriate study design were also excluded. Finally, 11 papers were included in the review. Among the reviewed papers, 8 papers validated the application of the EER(IOM) equations for EER based on TEE(DLW). These included 3 studies for children (USA 1, Korea 2), 1 for adolescents (Portugal), 2 for adults (Korean), and 2 for the elderly (Korea, USA).EER(IOM) equations were found to be generally acceptable for determining EER by using the DLW method, except for Korean boys at 9–11 yrs (overestimated) and female athletes at 19–24 yrs (underestimated). Additionally, 5 papers include the validation of other EER equations, beside EER(IOM) for EER based on TEE(DLW). In Japanese dietary reference intake and recommended dietary allowance, EER equations are acceptable for determining EER based on TEE(DLW). The EER(IOM) equations is generally acceptable for determining EER using the DLW method in Koreans as well as several populations, although certain defined groups were found to be unfit for the estimation. Additionally, the concept of healthy body mass index of Koreans and physical activity levels need to be considered, thereby providing the basis for developing relevant equations of EER in KDRI.

BACKGROUND/OBJECTIVES: Resveratrol, a natural polyphenol, has multiple functions in cellular responses including apoptosis, survival, and differentiation. It also participates in the regulation of inflammatory response and oxidative stress. MicroRNA-Let-7A (miR-Let7A), known as a tumor suppressor miRNA, was recently reported to play a crucial role in both inflammation and apoptosis. Therefore, we examined involvement of miR-Let7A in the modulation of inflammation and cell survival/apoptosis regulated by resveratrol. MATERIALS/METHODS: mRNA expression of pro-/anti-inflammatory cytokines and sirtuin 1 (SIRT1), and protein expression of apoptosis signal-regulating kinase 1 (ASK1), p-ASK1, and caspase-3 and cleaved caspase-3 were measured, and cell viability and Hoechst/PI staining for apoptosis were observed in Lipopolysaccharide (LPS)-stimulated human THP-1 macrophages with the treatment of resveratrol and/or miR-Let7A overexpression. RESULTS: Pre-treatment with resveratrol (25-200 µM) resulted in significant recovery of the reduced cell viabilities under LPS-induced inflammatory condition and in markedly increased expression of miR-Let7A in non-stimulated or LPS-stimulated cells. Increased mRNA levels of tumor necrosis factor-α and interleukin (IL)-6 induced by LPS were significantly attenuated, and decreased levels of IL-10 and brain-derived neurotrophic factor were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. Decreased expression of IL-4 mRNA by LPS stimulation was also significantly increased by miR-Let7A overexpression co-treated with resveratrol. In addition, decreased SIRT1 mRNA levels, and increased p-ASK1 levels and PI-positive cells by LPS stimulation were significantly restored by resveratrol and miR-Let7A overexpression, respectively, or in combination. CONCLUSIONS: miR-Let7A may be involved in the inflammatory response and cell survival/apoptosis modulated by resveratrol in human THP-1 macrophages.
Apoptosis ; Brain-Derived Neurotrophic Factor ; Caspase 3 ; Cell Survival ; Cytokines ; Humans ; Inflammation ; Interleukin-10 ; Interleukin-4 ; Interleukins ; Macrophages* ; MAP Kinase Kinase Kinase 5 ; MicroRNAs ; Necrosis ; Oxidative Stress ; RNA, Messenger ; Sirtuin 1

This study aimed to investigate the association of Apolipoprotein B (ApoB) with the risk of diabetes in Koreans. Korean men (n = 790, 40-79 years) who had been never diagnosed for diabetes before participating were enrolled. Subjects were categorized into normal fasting glucose (NFG, n = 519), impaired fasting glucose (IFG, n = 188) and newly-onset diabetes (n = 83) according to fasting glucose levels. Age was not significantly different among the subgroups. Mean values of BMI, waist circumference, Blood pressure(BP), triglyceride, non-HDL cholesterol were significantly higher in IFG or newly-onset diabetic subjects compared to NFG subjects. The levels of glucose, insulin, free fatty acid, insulin resistance and ApoB were highest in diabetic patients and lowest in NFG subjects. According to ApoB level, subjects were divided into two groups (high-ApoB group: ≥ 87.0 mg/dL vs. low-ApoB group: < 87.0 mg/dL). The risk of diabetes was higher in the high-ApoB group than the low-ApoB group [OR₀: 2.392, (95% CI: 1.470-3.893), P₀< 0.001]. This association was maintained after adjusted for age and BMI [OR₁: 2.228, (95% CI: 1.362-3.646), P₁ = 0.001] and further adjustment for blood pressure, triglyceride, HDL-cholesterol, LDL-cholesterol, non-HDL-cholesterol, ApoA1 and adiponectin [OR₂: 1.984, (95% CI: 1.001-4.064), P₂ = 0.049]. The association was much greater in subjects with metabolic syndrome (MetS) [OR₁: 2.805 (95% CI: 1.137-5.737), P₁ = 0.005] than in those without [OR₁: 1.917 (95% CI: 0.989-3.718), P₁ = 0.054]. After 3-month, further investigation was randomly performed in subjects with NFG or IFG who agreed to reinvestigation. Multiple stepwise regression analysis revealed that net change of ApoB levels was a main contributor to the net change of glucose levels (standardized b-coefficient: 0.315, p = 0.002). In conclusion, ApoB levels are closely associated with the increased risk of diabetes in Korean men.
Adiponectin ; Apolipoproteins B ; Apolipoproteins* ; Blood Pressure ; Cholesterol ; Fasting ; Glucose ; Humans ; Insulin ; Insulin Resistance ; Male ; Triglycerides ; Waist Circumference

Stroke leads to a variety of pathophysiological conditions such as ischemic infarct, cerebral inflammation, neuronal damage, cognitive decline, and depression. Many endeavors have been tried to find the therapeutic solutions to attenuate severe neuropathogenesis after stroke. Several studies have reported that a decrease in the neuropeptide regulator ‘galanin’ is associated with neuronal loss, learning and memory dysfunctions, and depression following a stroke. The present review summarized recent evidences on the function and the therapeutic potential of galanin in post-ischemic stroke to provide a further understanding of galanin's role. Hence, we suggest that galanin needs to be considered as a therapeutic factor in the alleviation of post-stroke pathologies.
Depression ; Galanin ; Inflammation ; Learning ; Memory ; Neurons ; Neuropeptides ; Pathology ; Stroke

The aim of this study was to investigate the influencing factors that characterize low density lipoprotein (LDL) phenotype and the levels of LDL particle size in healthy Korean women. In 57 healthy Korean women (mean age, 57.4 +/- 13.1 yrs), anthropometric and biochemical parameters such as lipid profiles and LDL particle size were measured. Dietary intake was estimated by a developed semi-quantitative food frequency questionnaire. The study subjects were divided into two groups: LDL phenotype A (mean size: 269.7A, n = 44) and LDL phenotype B (mean size: 248.2A, n = 13). Basic characteristics were not significantly different between the two groups. The phenotype B group had a higher body mass index, higher serum levels of triglyceride, total-cholesterol, LDL-cholesterol, apolipoprotein (apo)B, and apoCIII but lower levels of high density lipoprotein (HDL)-cholesterol and LDL particle size than those of the phenotype A group. LDL particle size was negatively correlated with serum levels of triglyceride (r = -0.732, P < 0.001), total-cholesterol, apoB, and apoCIII, as well as carbohydrate intake (%En) and positively correlated with serum levels of HDL-cholesterol and ApoA1 and fat intake (%En). A stepwise multiple linear regression analysis revealed that carbohydrate intake (%En) and serum triglyceride levels were the primary factors influencing LDL particle size (P < 0.001, R2 = 0.577). This result confirmed that LDL particle size was closely correlated with circulating triglycerides and demonstrated that particle size is significantly associated with dietary carbohydrate in Korean women.
Apolipoproteins ; Apolipoproteins B ; Body Mass Index ; Dietary Carbohydrates ; Female ; Humans ; Linear Models ; Lipoproteins ; Particle Size ; Phenotype ; Surveys and Questionnaires ; Triglycerides

This study aimed to investigate the relationship between meal regularity (i.e. breakfast intake and meal-times), and the risk of metabolic syndrome (MetS) among generally healthy Korean single-person household adults (≤60 years, n=594) based on the Seventh Korean National Health Examination and Nutrition Survey (KNHANES) (2016∼2018).Among men (n=325), the breakfast intake frequency was not significantly associated with the pervalence of MetS. However, men consuming a regular meal at least once a day showed a lower prevalence of MetS compared to those whose meals were irregular. These patterns remained after adjusting for age, smoking and drinking habits, individual income, education level, exercise, and total calorie intake. An association between meal regularity and MetS risk was observed in post-menopausal women (n=84), but not in pre-menopausal women (n=185). More specifically post-menopausal women with irregular breakfast eating habits or eating no breakfast at all showed a significantly higher risk of MetS than those eating breakfast regularly after the adjustment. The analysis revealed an odds ratio (OR) of 8.46, confidence intervals (CIs): 1.149∼62.199, P＜0.05 in irregular breakfast eaters, and an OR of 13.377, CIs: 1.665∼ 107.511, P＜0.05, in those who ate no breakfast. Furthermore, post-menopausal women who had irregular meals daily showed a higher risk of MetS than those consuming one or more regular meals/day after the adjustment (OR:16.888, CIs: 1.258∼226.655, P＜0.05). In conclusion, the results from this study may be used for formulating optimal dietary guidelines for the prevention and the management of MetS in adults in single-person households.

The prevalence of obesity in adults and children is rapidly increasing worldwide. Obesity is among the main causes of chronic diseases and various problems, including economic consequences and they can also be affected by genetic, environmental, psychological, and socioeconomic factors. Dietary modification is a well-known and important factor in weight control, in particular, dietary macronutrient composition, food selection, dietary patterns, and energy restriction can affect weight reduction. Therefore, this systematic review aims to provide basic evidence for identifying the optimal macronutrient composition for managing obesity in Korean children and adolescents. We searched literature through an international database, studies were selected using our eligibility criteria and quality was assessed via a risk of bias tool. In our results, several studies have demonstrated that dietary macronutrient modifications affect body composition and metabolic markers in children and adolescents. In contrast, hypocaloric diets, regardless of macronutrient composition, are reportedly effective for weight loss in obese children. However, these findings were based on intervention studies that examined the association between dietary macronutrient composition and obesity in non-Korean children and adolescents. Therefore, in the future, more intervention studies are needed to elucidate this relationship and evidence between macronutrients and obesity in Korean children and adolescents.

The prevalence of obesity in adults and children is rapidly increasing worldwide. Obesity is among the main causes of chronic diseases and various problems, including economic consequences and they can also be affected by genetic, environmental, psychological, and socioeconomic factors. Dietary modification is a well-known and important factor in weight control, in particular, dietary macronutrient composition, food selection, dietary patterns, and energy restriction can affect weight reduction. Therefore, this systematic review aims to provide basic evidence for identifying the optimal macronutrient composition for managing obesity in Korean children and adolescents. We searched literature through an international database, studies were selected using our eligibility criteria and quality was assessed via a risk of bias tool. In our results, several studies have demonstrated that dietary macronutrient modifications affect body composition and metabolic markers in children and adolescents. In contrast, hypocaloric diets, regardless of macronutrient composition, are reportedly effective for weight loss in obese children. However, these findings were based on intervention studies that examined the association between dietary macronutrient composition and obesity in non-Korean children and adolescents. Therefore, in the future, more intervention studies are needed to elucidate this relationship and evidence between macronutrients and obesity in Korean children and adolescents.