Structural, antioxidant, and immunomodulatory activities of an acidic exopolysaccharide from Lactiplantibacillus plantarum DMDL 9010.

This study investigated the structural, antioxidant, and immunomodulatory activities of acidic exopolysaccharide (EPS-LP2) isolated from Lactiplantibacillus plantarum DMDL 9010. EPS-LP2 is composed of fucose (Fuc), arabinose (Ara), galactose (Gal), glucose (Glc), mannose (Man), and D-fructose (Fru) with a molar ratio of 0.13: 0.69: 8.32: 27.57: 62.07: 0.58: 0.46, respectively. Structural analysis of EPS-LP2 exhibited a smooth irregular lamellar surface, rod-like structure with swollen ends and slippery surfaces, and good thermal stability. Based on the methylation and NMR analysis, sugar residues including t-Manp, t-Glcp, 2-Manp, 6-Galp, 6-Glcp, and 4-Glcp were found to exist in EPS-LP2. In the 50∼400 µg/ml range, EPS-LP2 showed negligible neurotoxicity to RAW264.7 cells. Moreover, EPS-LP2 could protect RAW264.7 cells from oxidative injury by lowering the generation of reactive oxygen species (ROS), malondialdehyde (MDA), and the secretion of lactate dehydrogenase (LDH). In contrast, an increase in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and the concentrations of glutathione (GSH) were observed. Immunoreactivity assays showed that EPS-LP2 could suppress the expression of NO, tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) and inhibit the activation of the mitogen-activated protein kinase (MAPK)/nuclear factor-κB-gene binding (NF-κB) cell pathway. Conclusively, EPS-LP2 could be a potential natural antioxidant and immunomodulatory agent in functional foods and medicines.

Reduced Serum Levels of Brain-Derived Neurotrophic Factor Are Related to Mild Cognitive Impairment in Chinese Patients with Type 2 Diabetes Mellitus.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is involved in obesity, type 2 diabetes mellitus (T2DM), and cognitive dysfunction. The present study sought to assess the role of serum levels of BDNF in the pathophysiological process of mild cognitive impairment (MCI), a preclinical phase of dementia in 715 Chinese patients with T2DM. METHODS: Cross-sectional data were obtained from 715 patients with T2DM recruited from a Chinese diabetes center. Serum levels of BDNF were measured with sandwich enzyme-linked immunosorbent assay. The influence of BDNF on MCI was examined using univariate and multivariate binary logistic regression analyses. RESULTS: In univariate and multivariate logistic regression analyses, for each one-unit increase of BDNF, the unadjusted and adjusted risk of MCI decreased by 9% (OR 0.91; 95% CI 0.88-0.93, p < 0.001) and 6% (0.94; 0.87-0.98, p < 0.001) respectively. In multivariate models comparing the first (Q1), second and third quartiles against the fourth quartile of BDNF, BDNF in Q1 and Q2 were associated with MCI, and increased risk of MCI by 275% (OR 3.75; 95% CI 2.38-6.03) and 155% (2.55; 1.32-4.02). These results suggested that for each 1 ng/mL increase of serum level of BDNF, the association became stronger among obese diabetic patients (OR 0.91, 95% CI 0.85-0.96; p < 0.001) versus nonobese diabetic patients (OR 0.95, 95% CI 0.86-0.98; p = 0.001). CONCLUSION: The present data demonstrated that reduced serum levels of BDNF were associated with increased risk of MCI and might be useful for identifying diabetic patients at risk of dementia for early prevention strategies.

[Correlation between ectopic fat accumulation and insulin sensitivity in obese individuals with different glucose tolerance levels].

OBJECTIVE: To investigate the correlation between liver and skeletal muscle fat contents and insulin resistance in obese individuals with different levels of glucose tolerance. METHODS: RESULTS: Ten non-obese individuals with normal glucose tolerance (NGT), 9 obese individuals with NGT, and 7 obese individuals with impaired glucose tolerance (IGT) were enrolled in this study. All the participants were examined for insulin sensitivity by hyperinsulinemic-euglycemic clamp and for liver and skeletal muscle fat accumulation quantified by proton magnetic resonance spectroscopy (1H MRS). The data were collected from the subjects including somatometric measurements, fasting plasma glucose, 2-h plasma glucose (2hPG), fasting insulin, and blood biochemistry. Linear correlation analysis and multiple linear stepwise regression analysis were used to analyze the relationship between ectopic fat accumulation and insulin resistance. RESULTS: The glucose infusion rates (GIR, presented as the M value) differed significantly among IGT-obese (3.95∓1.66 mg·kg-1·min-1), NGT-obese (6.14∓1.90 mg·kg-1·min-1) and NGT-non-obese (8.78∓2.46 mg·kg-1·min-1) groups (P<0.05). The 3 groups also showed significant differences in liver fat contents [(15.23∓3.09)%, (6.25∓0.38)%, and (1.89∓0.90)%, respectively, P<0.05] and intramyocellular lipids in the tibialis anterior (2.69∓0.95, 2.61∓1.45, and 1.54∓0.66 mmol/kg, respectively, P<0.05). Linear analysis revealed that liver fat content, but not skeletal muscle fat content, was significantly correlated with the M value. Multiple linear stepwise regression analysis using M value as the dependent variable (Y) revealed that liver fat content (X) was an independent factor inversely correlated with the M value (regression equation: Y=-30.562X+9.007, R2=0.717, P<0.01). CONCLUSIONS: Liver fat accumulation, but not skeletal muscle fat accumulation, is correlated with insulin resistance and impaired glucose metabolism.

Characteristics of morphology, electrophysiology, and central projections of two sensilla styloconica in Helicoverpa assulta larvae.

The medial and lateral styloconic sensilla, constituting the main taste organs of lepidopterous caterpillars, were investigated in the oligophagous species, Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae). In this paper, the two sensilla were morphologically and physiologically characterized by scanning electron microscopy and tip recordings, respectively. The central projections of their respective sensory neurons were mapped by anterograde staining experiments combined with confocal laser scanning microscopy. The results showed that the two sensilla are in general morphologically similar. However, the size of the peg on the medial sensillum is significantly greater than that of the lateral. Tobacco leaf saps, sinigrin, and nicotine elicited strong responses from neurons housed by the medial sensillum, whereas sucrose activated primarily the lateral sensillum. All stained neurons in either sensillum showed a projection pattern involving axons entering the subesophageal ganglion through the ipsilateral maxillary and passing further on through the ipsilateral circumesophageal connective to the tritocerebrum of the brain. In the subesophageal ganglion, the axons targeted two areas: the ventrolateral section and the region near the neuromere midline. One distinction between the staining patterns originating from the two sensilla, however, is that axons arising from the medial sensillum, and not the lateral, give off some additional neural branches in the subesophageal ganglion including a few arborizations surrounding a tract, plus a long process extending posteriorly along the midline. Differences in the central projections derived from the two sensilla styloconica have not been reported previously.

[Expression of matrix metalloproteinase 2 in oral verruvous carcinoma and squamous cell carcinoma].

OBJECTIVE: To determine the expression of MMP2 mRNA in oral verruvous carcinoma and squamous cell carcinoma. METHODS: Thirty cases were divided into 3 groups: verruvous carcinoma (n = 10), well-differentiated squamous cell carcinoma (n = 15) and moderately or poorly differentiated squamous cell carcinoma (n = 5). Reverse transcription polymerase chain reaction (RT-PCR) was used to test the expression of MMP2 mRNA in the carcinoma tissues and matched normal tissues from 3 groups above. RESULTS: The expression of MMP2 mRNA in the carcinoma tissues was significantly higher than that in their matched normal tissues (P < 0.05). The expression of MMP2 mRNA in verruvous carcinoma was significantly higher than that in well-differentiated and moderately or poorly differentiated squamous cell carcinoma (P < 0.05). However, the expression of MMP2 mRNA was not obviously different between well-differentiated and moderately or poorly differentiated squamous cell carcinoma (P > 0.05). CONCLUSION: The expression of MMP2 mRNA in oral verruvous carcinoma and squamous cell carcinoma tissues was significantly higher than that in their matched normal tissues. The expression of MMP2 mRNA in verruvous carcinoma was significantly higher than that in squamous cell carcinoma.