Heon-Sang Jeong

Bio: Heon-Sang Jeong is an academic researcher from Chungbuk National University. The author has contributed to research in topics: Food science & Chemistry. The author has an hindex of 21, co-authored 123 publications receiving 1952 citations.

Anti-inflammatory and arthritic effects of thiacremonone, a novel sulfurcompound isolated from garlic via inhibition of NF-κB

Abstract: Sulfur compounds isolated from garlic exert anti-inflammatory properties. We recently isolated thiacremonone, a novel sulfur compound from garlic. Here, we investigated the anti-inflammatory and arthritis properties of thiacremonone through inhibition of NF-κB since NF-κB is known to be a target molecule of sulfur compounds and an implicated transcription factor regulating inflammatory response genes. The anti-inflammatory and arthritis effects of thiacremone in in vivo were investigated in 12-O-tetradecanoylphorbol-13-acetate-induced ear edema, carrageenan and mycobacterium butyricum-induced inflammatory and arthritis models. Lipopolysaccharide-induced nitric oxide (NO) production was determined by Griess method. The DNA binding activity of NF-κB was investigated by electrophoretic mobility shift assay. NF-κB and inducible nitric oxide synthetase (iNOS) transcriptional activity was determined by luciferase assay. Expression of iNOS and cyclooxygenase-2 (COX-2) was determined by western blot. The results showed that topical application of thiacremonone (1 or 2 μg/ear) suppressed the 12-O-tetradecanoylphorbol-13-acetate-induced (1 μg/ear) ear edema. Thiacremonone (1-10 mg/kg) administered directly into the plantar surface of hind paw also suppressed the carrageenan (1.5 mg/paw) and mycobacterium butyricum (2 mg/paw)-induced inflammatory and arthritic responses as well as expression of iNOS and COX-2, in addition to NF-κB DNA-binding activity. In further in vitro study, thiacremonone (2.5-10 μg/ml) inhibited lipopolysaccharide (LPS, 1 μg/ml)-induced nitric oxide (NO) production, and NF-κB transcriptional and DNA binding activity in a dose dependent manner. The inhibition of NO by thiacremonone was consistent with the inhibitory effect on LPS-induced inducible nitric oxide synthase (iNOS) and COX-2 expression, as well as iNOS transcriptional activity. Moreover, thiacremonone inhibited LPS-induced p50 and p65 nuclear translocation, resulting in an inhibition of the DNA binding activity of the NF-κB. These inhibitory effects on NF-κB activity and NO generation were suppressed by reducing agents dithiothreitol (DTT) and glutathione, and were abrogated in p50 (C62S)-mutant cells, suggesting that the sulfhydryl group of NF-κB molecules may be a target of thiacremonone. The present results suggested that thiacremonone exerted its anti-inflammatory and anti-arthritic properties through the inhibition of NF-κB activation via interaction with the sulfhydryl group of NF-κB molecules, and thus could be a useful agent for the treatment of inflammatory and arthritic diseases.

Anti-proliferate and pro-apoptotic effects of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyranone through inactivation of NF-κB in Human Colon Cancer Cells

Abstract: Many natural compounds have been shown to prevent cancer cell growth through the redox regulation of transcription factors. NF-κB, a redox transcription factor, has been implicated in the apoptotic cell death of several cancer cells. This study examined whether or nor 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyranone (DDMP) isolated from onions can modulate the activity of NF-κB, thereby induce the apoptotic cell death of colon cancer cells. Treatment with different DDMP concentrations (0.5–1.5 mg/mL) for various periods (0–48 h) inhibited the growth of colon cancer cells (SW620 and HCT116) followed by the induction of apoptosis in a dose dependent manner. It was also found that DDMP modulated tumor necrosis factor-α (TNF-α) and tetradeanoyl phorbol acetate (TPA)-induced NF-κB transcriptional and DNA binding activity. Moreover, DDMP suppressed the NF-κB target anti-apoptotic genes (Bcl-2), whereas it induced the expression of the apoptotic genes (Bax, cleaved caspase-3 and cleaved PARP). These results suggest that DDMP from onions inhibit colon cancer cell growth by inducing apoptotic cell death through the inhibition of NF-κB.

Mammalian caspases: structure ,a ctivation ,s ubstrates, and functions during apoptosis

Abstract: ■ Abstract Apoptosis is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli. Studies performed over the past 10 years have demonstrated that proteases play critical roles in initiation and execution of this process. The caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases. Caspases are synthesized as relatively inactive zymogens that become activated by scaffold-mediated transactivation or by cleavage via upstream proteases in an intracellular cascade. Regulation of caspase activation and activity occurs at several different levels: ( a) Zymogen gene transcription is regulated; ( b) antiapoptotic members of the Bcl-2 family and other cellular polypeptides block proximity-induced activation of certain procaspases; and ( c) certain cellular inhibitor of apoptosis proteins (cIAPs) can bind to and inhibit active caspases. Once activated, caspases cleave a variety of intracellular polypeptides, including major structural elements of the cytoplasm and nucleus, components of the DNA repair machinery, and a number of protein kinases. Collectively, these scissions disrupt survival pathways and disassemble important architectural components of the cell, contributing to the stereotypic morphological and biochemical changes that characterize apoptotic cell death.

Millet Grains: Nutritional Quality, Processing, and Potential Health Benefits

Abstract: In the 21st century, climate changes, water scarcity, increasing world population, rising food prices, and other socioeconomic impacts are expected to generate a great threat to agriculture and food security worldwide, especially for the poorest people who live in arid and subarid regions. These impacts present a challenge to scientists and nutritionists to investigate the possibilities of producing, processing, and utilizing other potential food sources to end hunger and poverty. Cereal grains are the most important source of the world's food and have a significant role in the human diet throughout the world. As one of the most important drought-resistant crops, millet is widely grown in the semiarid tropics of Africa and Asia and constitutes a major source of carbohydrates and proteins for people living in these areas. In addition, because of their important contribution to national food security and potential health benefits, millet grain is now receiving increasing interest from food scientists, technologists, and nutritionists. The aim of this work was to review the recent advances in research carried out to date for purposes of evaluation of nutritional quality and potential health benefits of millet grains. Processing technologies used for improving the edible and nutritional characteristics of millet as well as challenges, limitations, and future perspectives to promote millet utilization as food for a large and growing population are also discussed.

Phytochemical profiles and antioxidant activity of adlay varieties.

Abstract: Consumption of whole grains has been associated with reduced risk of developing major chronic diseases. These health benefits have been attributed in part to their unique phytochemicals. Little is known about the complete profiles of phytochemicals and antioxidant activities of different adlay varieties. The objectives of this study were to determine the phytochemicals profiles of the three adlay varieties, including both free and bound of total phenolics and total flavonoids, and to determine the total antioxidant activity of adlay. The free, bound, and total phenolic contents of adlay samples ranged from 31.23 to 45.19 mg of gallic acid equiv/100 g of sample, from 28.07 to 30.86 mg of gallic acid equiv/100 g of sample, and from 59.30 to 76.04 mg of gallic acid equiv/100 g of sample, respectively. On average, the bound phenolics contributed 45.3% of total phenolic content of the adlay varieties analyzed. The free, bound, and total flavonoid contents of adlay samples ranged from 6.21 to 18.24 mg of catechin equiv/100 g, from 18.68 to 35.27 mg of catechin equiv/100 g, and from 24.88 to 52.86 mg of catechin equiv/100 g, respectively. The average values of bound flavonoids contributed 71.1% of total flavonoids of the adlay varieties analyzed. The percentage contribution of flavonoid content to phenolic content of free, bound, and total ranged from 11.6 to 35.2%, from 50.5 to 66.8%, and from 24.6 to 50.5%. The free, bound, and total oxygen radical absorbance capacity (ORAC) values of adlay samples ranged from 231.9 to 316.6 mg of Trolox equiv/100 g, from 209.0 to 351.4 mg of Trolox equiv/100 g, and from 440.9 to 668.0 mg of Trolox equiv/100 g, respectively. The average ORAC values of bound phytochemicals contributed 48.1% of total antioxidant activity of the adlay varieties analyzed. The content of total polyphenol and the antioxidant capacity are obviously different among different species. Liaoning 5 adlay and Longyi 1 adlay are significantly better than Guizhou heigu adlay. The adlay extracts have obvious proliferate inhibition on human liver cancer cells, and substantially in the experimental concentration range, the adlay sample itself has no cytotoxicity. Knowing the phytochemical profiles and antioxidant activity of adlay gives insights to its potential application to promote health.