Anti-Obesity Effect and Signaling Mechanism of Potassium Poly-γ-Glutamate Produced by Bacillus subtilis Chungkookjang in High-Fat Diet-Induced Obese Mice.

The purpose of this work was to examine the effects of potassium poly-γ-glutamate (PGA-K) on mice fed a high-fat diet consisting of 60% of total calories for 12 weeks. PGA-K administration reduced the increase in body weight, epididymal fat, and liver weight caused by a high-fat diet compared to the obese group. The triglyceride, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels, which are blood lipid indicators, were significantly increased in the obese group but were significantly decreased in the PGA-K-treated group. The administration of PGA-K resulted in a significant inhibition of pro-inflammatory cytokines, including tumor necrosis factor α and interleukin 6. Moreover, the levels of leptin and insulin, which are insulin resistance indicators, significantly increased in the obese group but were significantly decreased in the PGA-K-treated group. These results suggest that PGA-K exhibits a protective effect against obesity induced by a high-fat diet, underscoring its potential as a candidate for obesity treatment.

Effects of ultra high molecular weight poly-gamma-glutamic acid from Bacillus subtilis (chungkookjang) on corneal wound healing.

Poly-gamma-glutamic acid (gamma-PGA) is a natural, edible polypeptide in which glutamate is polymerized via gamma-amide linkages. First, we assessed the eye irritancy potential of gamma PGA in rabbits. Additionally, we studied the effects of gamma-PGA on corneal wound healing, due to the anti inflammatory properties and water retaining abilities of gamma-PGA. In this study, the effects of gamma-PGA on corneal wound healing after an alkali burn were evaluated. Thirty eyes wounded by alkali burning in 30 white rabbits were divided into three groups: group A was treated with 0.1% 5000 kDa gamma-PGA for 2 days, group B was treated with 0.1% hyaluronic acid, and group C was not treated, as a control. The area of corneal epithelial defect was examined at 12, 24, 30, 36, 42, and 48 h after corneal alkali wounding to determine initial wound healing. We found that gamma-PGA promoted corneal wound healing, compared with controls, and showed similar effects to hyaluronic acid. These results indicate that gamma-PGA stimulates corneal wound healing by an anti inflammatory effect and enhancing cell migration and cell proliferation. gamma-PGA is a promising biomaterial that may be a substitute for hyaluronic acid in corneal wound healing treatment.

Association of the G134A and G184C Polymorphisms in the CYP1A1 Gene with Lung Cancer Incidence.

The G184C and G134A single nucleotide polymorphisms (SNPs) of the CYP1A1 gene result in Ala62Pro and Gly45Asp substitutions, respectively. Here, we tested whether these SNPs are associated with an alteration in lung cancer incidence. We examined 80 Korean subjects with lung cancer and 240 age- and sex-matched controls. For each subject, the CYP1A1 gene was PCR amplified and sequenced. We observed that the odds ratio (OR) for lung cancer was 3.37 higher in subjects with the G184C polymorphism than in controls (95% confidence interval (CI), 0.89~12.73, P = 0.07). In contrast, the OR for lung cancer was 1.23 in subjects with the G134A polymorphism compared to controls (95% CI, 0.68~2.20, P = 0.49). The G184C polymorphism exacerbated the effects of smoking on lung cancer development. Gene-smoking interaction analyses revealed that past or present smokers with the G184C polymorphism had a higher incidence of lung cancer (OR, 24.72; 95% CI, 4.48~136.31; P < 0.01) than control smokers (OR, 6.65; 95% CI, 2.72~16.28; P < 0.01). However, there was only a slight difference in the ORs for lung cancer between control smokers and smokers with the G134A polymorphism. These findings suggest that the G184C polymorphism, but not the G134A polymorphism, is associated with an increased risk of lung cancer.

Comparison of natural and Dumon airway stents for the management of benign tracheobronchial stenoses.

OBJECTIVE AND BACKGROUND: To investigate the utility and safety of the 'Natural stent', a newly designed silicone airway stent, the authors compared clinical outcomes and complications in patients who underwent silicone airway stenting for the management of benign airway stenosis. METHODS: The medical records of 94 patients requiring the placement of 100 airway stents (43 Dumon and 57 Natural) were retrospectively reviewed in a tertiary referral hospital. RESULTS: Post-tuberculous stenosis was the leading indication for airway stenting (74%), followed by post-intubation stenosis (21%). After intervention, dyspnoea improved in patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing dyspnoea, stents could be successfully removed in half of the patients who underwent Dumon (54%) or Natural (49%) stenting. During a 42-month follow-up period, complication rates were similar in patients who underwent Dumon or Natural stenting. CONCLUSION: Natural airway stent was as effective and safe as Dumon stent for the management of benign tracheobronchial stenoses.

A Peptide with anti-transglutaminase activity decreases lipopolysaccharide-induced lung inflammation in mice.

Octapeptide R2 (KVLDGQDP), which has anti-transglutaminas (TGase) activity, decreases inflammation in allergic conjunctivitis model in guinea pigs. The authors examined the effect of R2 on lipopolysaccharide (LPS)-induced lung injury in BALB/c mice. R2 inhalation significantly decreased neutrophil count and cytokine mRNA expression in the lungs of LPS (25 mg/kg)-treated mice (P < .05). It also showed a tendency for decreased tumor necrosis factor (TNF)-alpha-immunoreactive protein in lung homogenates and significantly decreased TNF-alpha-immunoreactive protein in the serum of LPS-injected mice (P < .05). These results indicate that TGase may be a new therapeutic target in LPS-induced lung inflammation.