The prevalence of IBS in the Korean population is 6.6%, and the male:female ratio is similar. Also, IBS is more frequent in younger subjects. Irritable bowel syndrome subjects visited a physician mostly due to abdominal pain.

Most studies of bowel habits have been conducted in Western countries. This study was conducted to estimate the epidemiology of constipation and the discrepancy between self-reported constipation and bowel habits in Koreans. Telephone interviews regarding bowel habits were conducted with a total of 1029 individuals in Korea, 15 years of age or older. Subjects were given a questionnaire which asked about bowel symptoms, sociodemographic associations, laxative use, and physician visits. Of all subjects 95.6% had a defecation frequency of between three per week and three per day. The prevalence was 16.5% for self-reported constipation, 9.2% for functional constipation (FC), and 3.9% for constipation-predominant irritable bowel syndrome (IBS-C). Of subjects' self-reporting constipation, proportions of FC and IBS-C were 21.8% and 23.5%, respectively. Of subjects excluding self-reported constipation, the proportion of FC was 6.8%. Prevalences of self-reported constipation and IBS-C were higher in females than in males (P < 0.001). Of subjects' self-reporting constipation, 8.2% used laxatives. We conclude that constipation is a common problem in the general Korean population.

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear receptor highly expressed in the colon and playing an anti-inflammatory role through inhibition of the NF-kappaB pathway. Toll-like receptor 4 (TLR4) has been known to mediate LPS-induced cellular signaling through activation of NF-kappaB pathway in intestinal epithelial cells. The aims of this study were to evaluate attenuation of inflammation by PPARgamma in intestinal epithelial cells and to study the possible relation between PPARgamma and TLR4. HT-29 human epithelial cells were stimulated with LPS (20 microg/ml) and PPARgamma ligand, 15d-PGJ2 (10 microM), or with LPS (20 microg/ml) alone for 24 hr. COX-2, IL-8, TLR4, and PPARgamma mRNA expression was assessed by RT-PCR. IL-8 protein levels and TLR4 protein expression were analyzed by ELISA and Western blot, respectively. To evaluate the action mechanisms of PPARgamma ligand, Western blot analysis for IkappaBalpha degradation was performed. Costimulation with LPS and PPARgamma ligand in comparison to LPS stimulation alone (1) decreased COX-2, IL-8 mRNA expression and IL-8 protein secretion, (2) decreased TLR4 mRNA and protein expression, and (3) decreased PPARgamma mRNA expression. PPARgamma ligand delayed LPS-induced IkappaBalpha degradation. These findings suggest that PPAR-gamma ligands suppress inflammation in intestinal epithelial cells. PPARgamma and TLR, these two antagonistic signaling pathways in intestinal epithelial cells may be partially cross-linked.

Carnitine and carnitine-lipoic acid prevent lipotoxicity by increasing mitochondrial β-oxidation and reducing intracellular oxidative stress.

Among 67 cases of AIP, either IgG or IgG4 was elevated in 76% of patients, and 14 patients (21%) had other organ involvement. New Korean diagnostic criteria are useful for diagnosis of AIP.