Hea-Jong Chung

Treatment of obesity with the resveratrol-enriched rice DJ-526

Obesity is the most prevalent disease in the world which poses a serious risk for various chronic diseases. However, currently there are not any therapeutic agents that reduce body weight without causing serious side effects. In order to prevent and/or treat obesity and related diseases through a nutraceutical approach, we created a resveratrol-enriched transgenic rice accumulating 1.4 μg/g of resveratrol in its grain, DJ-526. Feeding of mice with the resveratrol-enriched rice DJ-526 showed excellent anti-obesity effect with reduction of body weights and abdominal fat volumes compared to the control by 20.0% and 31.3%, respectively. Also, the consumption of the resveratrol-enriched rice DJ526 significantly improved the blood lipid profiles and glucose levels in the animal experiments. Our resveratrol-enriched rice DJ-526 rice could provide both safe and convenient way for people with obesity and related diseases without major change of lifestyle or unwanted side effects from medication.

Intestinal removal of free fatty acids from hosts by Lactobacilli for the treatment of obesity.

Recent findings on the association of gut microbiota with various diseases, including obesity, prompted us to investigate the possibility of using a certain type of gut bacteria as a safe therapeutic for obesity. Lactobacillus mutants with enhanced capacity in absorption of free fatty acids (FFAs) were isolated to show reduced absorption of FFAs by the administered host, attributing to inhibition of body weight gain and body fat accumulation as well as amelioration of blood profiles. Consequently, high throughput screening of natural FFAs‐absorbing intestinal microbes led to the isolation of Lactobacillus reuteri JBD30 l. The administration of Lactobacillus JBD30l lowered the concentration of FFAs in the gut fluid content of small intestine, thus reducing intestinal absorption of FFAs whereas promoting fecal excretion of FFAs. Animal data also confirmed that the efficacy of Lactobacillus JBD30l on body weight similar to that of orlistat, an FDA‐approved pharmaceutical for long‐term use to treat obesity. In a subsequent random, double‐blind, placebo‐controlled clinical trial (KCT0000452 at Clinical Research Information Service of Korea), there was a statistically significant difference in the percentage change in body weight between the Lactobacillus JBD301 and the placebo group (P = 0.026) as well as in the BMI (P = 0.036) from the 0‐week assessment to the 12‐week assessment. Our results show that FFA‐absorbing Lactobacillus JBD301 effectively reduces dietary fat absorption, providing an ideal treatment for obesity with inherent safety.

Novel preparation and characterization of human hair-based nanofibers using electrospinning process

Human hair-based biocomposite nanofibers (NFs) have been fabricated by an electrospinning technique. Aqueous keratin extracted from human hair was successfully blended with poly(vinyl alcohol) (PVA). The focus here is on transforming into keratin/PVA nanofibrous membranes and insoluble property of electrospun NFs. The resulting hair-based NFs were characterized using Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning colorimetry (DSC), and thermogravimetric analysis (TGA). Toward the potential use of these NFs after cross-linking with various weight fractions of glyoxal, its physicochemical properties, such as morphology, mechanical strength, crystallinity, and chemical structure were investigated. Keratin/PVA ratio of 2/1 NFs with 6 wt%-glyoxal showed good uniformity in fiber morphology and suitable mechanical properties, and excellent antibacterial activity providing a potential application of hair-based NFs in biomedical field.

Identification of an autosomal dominant locus for intracranial aneurysm through a model-based family collection in a geographically limited area

Intracranial aneurysm (IA) is characterized by an abnormal bulging of one of the arteries in the brain and is heavily affected by genetic factors. Although IA is a very serious disease because of its severity and prevalence in the general public, the gene causing IA has not yet been identified due mainly to the lack of definitive genetic loci for the disease. Following a model-based family collection that recruited families from a geographically limited area that inherited IA as an autosomal dominant trait, we conducted a genome-wide linkage analysis. Significant evidence of linkage to IA was found on chromosome 8p22.2 with a maximum two-point logarithm of the odds ratio score of 3.61 under an autosomal dominant model of inheritance. The methods described in this study could be applied to localize disease-causing genes of other complex diseases through either a genome-wide linkage analysis or a genome-wide association study.

Pharmabiotics as an Emerging Medication for Metabolic Syndrome and Its Related Diseases

Metabolic syndrome (MetS) is a cluster of metabolic risk factors associated with central obesity, hyperglycemia, insulin resistance, dyslipidemia and high blood pressure. In recent decades, because of the remarkable increase in both prevalence and severity, MetS and its related diseases such as cardiovascular diseases (CVDs), obesity, hypertension and diabetes have become the main global burden and challenge in strategic management involving prevention and treatment. However, currently, the preventions and treatments based on pharmaceutical interventions do not provide a solution for MetS and its related diseases. Recently, gut microbiota showed clear evidence of preventing and/or treating MetS, shedding light on treating MetS and its related diseases through a completely different approach. In this review, we will interpret the effects of current pharmaceutical drugs used in preventing and treating MetS and its related diseases to understand remaining issues of those interventions. We will explore the possibility of developing gut microbiota as pharmabiotics in a completely new medication option for treating MetS and its related diseases.

Biocompatible and photoluminescent keratin/poly(vinyl alcohol)/carbon quantum dot nanofiber: A novel multipurpose electrospun mat

Carbon quantum dots (C-dots) triggered photoluminescent keratin/poly(vinyl alcohol) (PVA)/C-dots nanofibers (NFs) with optical transparency and biocompatibility were prepared by an electrospinning process. The synthesized NFs were characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy, and spectrofluorometer. C-dots are capable of emitting excitation dependent photoluminescence (PL) emission spectra at room temperature and are nontoxic at reasonably high concentrations. Optically transparent keratin/PVA/C-dots NFs were found to exhibit excitation dependent PL emission at the wavelengths of 488, 535, and 625 nm during excitation at the wavelengths of 360, 480, and 545 nm, respectively, similar to the C-dots. In vitro cytotoxicity tests against NIH-3T3 cell lines revealed a good biocompatible nature of keratin/PVA/C-dots. The results indicated that the fabricated composite NFs mat not only exhibited a well preserved quantum confinement effect of the C-dots along with its transparency but also showed biocompatibility in the living cell environment.

The resveratrol-enriched rice DJ526 boosts motor coordination and physical strength.

The main objective of current genetic modifications in crops is to boost agricultural production or to develop GM crops with an improved nutrient profile by introducing a new trait to the plants. A GM crop surpassing the ability of the introduced genetic characteristics has not been developed yet. Here, we show that the resveratrol-enriched rice DJ526, a GM crop, has unexpectedly high beneficial health effects surpassing the introduced genetic characteristic of resveratrol synthetic ability. The synergistic effect of its innate and transgenic properties not only ameliorates age-related deterioration but also boosts motor coordination and physical strength during the aging process. The gene expression profiling analyses by DNA chip showed that the gene expression pattern of mice fed resveratrol-enriched rice DJ526 was very different from mice fed either resveratrol or Dongjin rice alone, respectively, modifying expression of genes related to aging regulation, cell differentiation, extracellular matrix, neurogenesis, or secretion.

The Pharmabiotic Approach to Treat Hyperammonemia

Ammonia is constantly produced as a metabolic waste from amino acid catabolism in mammals. Ammonia, the toxic waste metabolite, is resolved in the liver where the urea cycle converts free ammonia to urea. Liver malfunctions cause hyperammonemia that leads to central nervous system (CNS) dysfunctions, such as brain edema, convulsions, and coma. The current treatments for hyperammonemia, such as antibiotics or lactulose, are designed to decrease the intestinal production of ammonia and/or its absorption into the body and are not effective, besides being often accompanied by side effects. In recent years, increasing evidence has shown that modifications of the gut microbiota could be used to treat hyperammonemia. Considering the role of the gut microbiota and the physiological characteristics of the intestine, the removal of ammonia from the intestine by modulating the gut microbiota would be an ideal approach to treat hyperammonemia. In this review, we discuss the significance of hyperammonemia and its related diseases and the efficacy of the current management methods for hyperammonemia to understand the mechanism of ammonia transport in the human body. The possibility to use the gut microbiota as pharmabiotics to treat hyperammonemia and its related diseases is also explored.

Blood Ammonia as a Possible Etiological Agent for Alzheimer’s Disease

Alzheimer’s disease (AD), characterized by cognitive decline and devastating neurodegeneration, is the most common age-related dementia. Since AD is a typical example of a complex disease that is affected by various genetic and environmental factors, various factors could be involved in preventing and/or treating AD. Extracellular accumulation of beta-amyloid peptide (Aβ) and intracellular accumulation of tau undeniably play essential roles in the etiology of AD. However, interestingly enough, medications targeting Aβ or tau all failed and the only clinically efficient medications for AD are drugs targeting the cholinergic pathway. Also, a very intriguing discovery in AD is that the Mediterranean diet (MeDi), containing an unusually large quantity of Lactobacilli, is very effective in preventing AD. Based on recently emerging findings, it is our opinion that the reduction of blood ammonia levels by Lactobacilli in MeDi is the therapeutic agent of MeDi for AD. The recent evidence of Lactobacilli lowering blood ammonia level not only provides a link between AD and MeDi but also provides a foundation of pharmabiotics for hyperammonemia as well as various neurological diseases.

Ultra-High Efficient Colony PCR for High Throughput Screening of Bacterial Genes

Current colony PCR methods are not suitable for screening genes encoded in genomic DNA and are limited to E. coli host strains. Here, we describe an ultra-high efficient colony PCR method for high throughput screening of bacterial genes embedded in the genomic DNA of any bacterial species. This new technique expands colony PCR method to several hosts as well as offers a rapid, less expensive and reliable bacterial genomic DNA extraction.