Effect of ß-hydroxy-ß-methylbutyrate (HMB) on the Muscle Strength in the Elderly Population: A Meta-Analysis.

Objective: This meta-analysis aims to evaluate the effect of the emerging nutritional ingredient ß-hydroxy-ß-methylbutyrate (HMB) on the muscle strength of elderly people. Methods: Computer systems-based search and sorting of relevant documents published before December 2020 in the China Journal Full-text Database (CNKI), Wan Fang Database (Wan Fang), VIP Chinese Science and Technology Journal Database (VIP), PubMed, Web of Science, and EMbase Database was done. Two researchers independently screened the literature based on the inclusion and exclusion criteria and performed data extraction and quality evaluation. Rev Man 5.X software was used for systematic review and meta-analysis. Results: A total of 9 randomized controlled trials (RCT) studies were included in the study, which comprised 896 subjects. The overall impact on muscle strength-related indicators (SMD = 0.41; 95% CI: 0.28, 0.54); p < 0.00001) was statistically significant. Conclusion: Supplementation of HMB and preparations containing HMB ingredients aid in increasing muscle strength in the elderly population.

Protective Effects of Five Structurally Diverse Flavonoid Subgroups against Chronic Alcohol-Induced Hepatic Damage in a Mouse Model.

Alcoholic liver disease (ALD) has become one of the major global health problems, with augmented morbidity and mortality. Evidence indicates that flavonoids can reduce the risk of ALD owing to their biological properties. However, the effect of structurally different flavonoid subclasses on alleviating alcohol-induced liver damage in a same model has never been studied. In this study, mice were supplemented with five kinds of flavonoid subgroups, apigenin (flavone), quercetin (flavonol), naringenin (flavanone), (-)-epigallocatechin gallate (flavanol), and genistein (isoflavone), in the same dose (0.3 mmol kg-1 body weight) and then given 50% alcohol by gastric perfusion for five consecutive weeks. The results demonstrated that genistein and naringenin had greater benefits in terms of mitigating fibrosis and apoptosis, respectively, in the liver. Lipid deposition, partial inflammatory-related factors (nuclear factor kappa B p65, cyclooxygenase-2, and interleukin-6 levels), and hepatic histopathological alterations were similarly attenuated by five kinds of flavonoids. All the flavonoids also showed different degrees of influence on protecting against alcoholic liver injury on other aspects, such as serum biochemistry makers, hepatic lipid accumulation, lipid peroxidation, antioxidant capacities, and inflammation.

Structure-activity relationship study of antioxidative peptides by QSAR modeling: the amino acid next to C-terminus affects the activity.

Screening, isolation and in vitro assays have been used for characterization of antioxidative peptides derived from food proteins, and incompatible deductions of structural characteristics derived from the isolated peptides have been brought forward. However, there is still little information concerning the structure-activity relationship of antioxidative peptides. QSAR modeling was performed, respectively, on synthetic tripeptides and tetrapeptides related to LLPHH. According to cumulative squared multiple correlation coefficients (R(2)), cumulative cross-validation coefficients (Q(2)) and relative standard deviation for calibration set (RSD(c)), two credible models for tripeptide and tetrapeptide databases, respectively, have been built with partial least squares (PLS) regression (R(2) for models of tripeptide and tetrapeptide are 0.744 and 0.943, Q(2) are 0.631 and 0.414, and RSD(c) are 0.323 and 0.111, respectively). Meanwhile, according to the cumulative multiple correlation coefficient for the predictive set (R2(ext)) and the relative standard deviation for the predictive set (RSD(p)), the predictive ability of the model for tripeptides also is excellent (R2(ext)) and RSD(p) are 0.719 and 0.450, respectively). Hydrogen bond property and hydrophilicity of the amino acid residue next to the C-terminus, and the hydrophobicity as well as electronic propertyof the N-terminus are more significant; meanwhile, the electronic property of the C-terminus is beneficial for antioxidant activity. The structural characteristics we found are very useful in understanding and predicting the peptide structures responsible for activity and development of functional foods with peptides as active compounds, or antioxidative peptides as alternatives to other antioxidants.

Preparation and identification of generic antigens and broad-spectrum monoclonal antibodies for detection of organophosphorus pesticides.

A simple, rapid, and high-sensitivity assay was developed to detect the multiresidue of organophosphorus pesticides (OPs) in the environment and food. Two separate generic haptens (Hapten A and B) with same O,O-dimethyl phosphorothioate group and aromatic ring and different spacer arms were synthesized and conjugated to bovine serum albumin (BSA) for immunogens and to ovalbumin (OVA) for coating antigens to study the effect of hapten and coating antigen heterology on immunoassay sensitivity. A broad-spectrum monoclonal antibody (MAb) was produced and a competitive ELISA developed using Hapten B-BSA as the immunogen and Hapten A-OVA as the coating antigen for the multiresidue determination of OPs, including parathionmethyl, fenitrothion, fenthion, chlorthion, and fenchlorphos. Several assay conditions, including organic solvent, pH, ionic strength, and incubation time, were studied sequentially to optimize the immunoassay. Using the optimal assay, 50% inhibition concentration values were estimated to be 34.5, 47.5, 79.8, 125.2, and 373.1 ng/mL for parathionmethyl, fenitrothion, fenthion, chlorthion, and fenchlorphos, respectively. The results indicated that the MAb showed specificity to all the above five OPs, and the assay could be developed for multiresidue determinations.

[Synthesis and identification of artificial antigen to the common moiety of some organophosphorus pesticides].

OBJECTIVE: To develop an immunoassay for multiple residues of organophosphorus pesticides. METHODS: The generic hapten O, O-dimethyl-O-(4-carboxyphenyl)ester (HP) was synthesized by the reaction between O, O-Dimethyl phosphorochloridothionate and 4-hydroxybenzoic acid methyl ester, and then conjugated to bovine serum albumin (BSA) by active ester method for immunogens and ovalbumin (OVA) by mixed anhydride reaction for coating antigens. RESULTS: The hapten was synthesized successfully, which was characterized by MS. The coupling ratios were 15.6:1 (HP-BSA) and 16.2:1(HP-OVA), respectively, calculated by UV spectrophotometry. CONCLUSION: suggested that the artificial antigens could be used for production of broad specificity anti-organophosphorous pesticides antibody.

Antihyperglycemic activity of Prunella vulgaris L. in streptozotocin-induced diabetic mice.

Prunella vulgaris L. (Labiatae) has been reported to have a wide range of health benefits in oriental medicine. This study for the first time is to examine the antihyperglycemic effects of P. vulgaris in streptozotocin (STZ)-induced diabetic ICR mice (STZ diabetic mice). The effects of P. vulgaris L. aqueous-ethanol extract (PVE) on blood glucose, exogenous insulin sensitivity and plasma insulin levels were investigated. In four doses of extracts from the spikes of P. vulgaris, extract at dose of 100 mg/kg significantly suppressed the rise in blood glucose after 30 min in the acute glucose tolerance test. Furthermore, this dose was applied in the fellow experiments. A significant decrease in blood glucose levels was observed after treatment of PVE. A combination of PVE and glibenclamide produced a greater effect in blood glucose level than using glibenclamide or PVE alone. PVE enhanced and prolonged the antihyperglycemic effects of exogenous insulin on STZ diabetic mice. Plasma insulin levels were increased with glibenclamide treatment in STZ diabetic mice, whereas such effect was not observed with PVE. These results indicated that P. vulgaris enhances the antihyperglycemic effects of exogenous insulin without stimulating insulin secretion, indicating that insulin sensitivity is increased in STZ diabetic mice.

Antihyperglycemic effects of Platycodon grandiflorum (Jacq.) A. DC. extract on streptozotocin-induced diabetic mice.

The root of Platycodon grandiflorum (Jacq.) A. DC has been reported to have a wide range of health benefits in oriental food. This study examined the hypoglycemic effects of Platycodon grandiflorum (Jacq.) A. DC aqueous-ethanol extract (PGE) in streptozotocin (STZ) -induced diabetic ICR mice (STZ diabetic mice) for the first time. The effects of PGE on blood glucose, plasma insulin levels and body weight were investigated. A significant decrease in blood glucose levels was observed after single administration of PGE. Furthermore, Glibenclamide and PGE significantly suppressed the rise in blood glucose after 30 min in the acute glucose tolerance test. Treatment with glibenclamide and PGE resulted in a reduction in blood glucose levels from the 2nd week, and this reduction was maintained until the 4th week of treatment. The body weight changed slightly in glibenclamide and PGE treated mice in comparison with the STZ control group. Plasma insulin levels were increased with glibenclamide treatment in STZ diabetic mice, whereas such effect was not observed with PGE. These results indicated that PGE could induce hypoglycemic effects without stimulating insulin secretion.

Effect of Panax notoginseng saponins on lipopolysaccharide-induced adhesion of leukocytes in rat mesenteric venules.

Panax notoginseng is the root of the Chinese traditional herb, Panax notoginseng (Burk) F.H. Chen. This study was aimed to investigate the inhibitory effect of Panax notoginseng saponins (PNS) on the leukocyte adhesion and the expression of adhesion molecules in rat mesentery venules. Male Sprague-Dawley rats were anesthetized with urethane. These were divided into control, LPS (perfused with lipopolysaccharide), and PNS group (perfused with PNS). The mesenteric microcirculation was observed under a videomicroscope. The number of adherent leukocytes, which attached to the vascular wall during more than 10 seconds, was counted along single venules (30-50 microm in diameter, 200 microm in length). The expression of adhesion molecules was examined using flow-cytometry in blood which was taken from the abdominal aorta and incubated with FITC-labeled CD11b (or CD18) antibodies. The results showed that different changes in the leukocyte adhesion and the expression of adhesion molecules among three groups. In LPS group, the leukocyte adhesion increased significantly after 20 minutes during the observation time, while it was reduced markedly in PNS group. The expression of CD11b and CD18 on the neutrophils was induced in LPS group, while it was reduced significantly in PNS group. It was suggested that PNS could reduce leukocyte adhesion in venules under the inhibitory effect on the expression of adhesion molecules (CD11b and CD18) on neutrophils.

[Determination of the contents of resveratrols and piceids in wines by high performance liquid chromatography with solid phase extraction].

A method has been developed for the determination of the contents of cis- and trans-resveratrols and piceids in wines by high performance liquid chromatography (HPLC) with solid phase extraction (SPE). The techniques of SPE including the activation of the SPE column, elimination of interference and elution conditions of samples were confirmed. The analytes were separated by using a Hypersil C18 column (4.6 mm i. d. x 250 mm, 5 microm) and acetonitrile-water as mobile phase with linear gradient elution. A photodiode array detector monitored at the detection wavelengths of 288 nm and 306 nm for cis- and trans-isomers, respectively. The external standard calibration curves were used in quantitation. There were good linear correlations between the concentrations and peak areas of the four components with the correlation coefficients of 0.9973-0.9999. The average recoveries were 97.4%-98.6% with relative standard deviations of 2.1%-3.2%. The detection limits were 0.002-0.005 mg/L. The method of SPE-HPLC eliminated a great deal of interferences in wines effectively by optimizing extraction conditions. The four isomers were well separated and the analytical results were improved well and truly. The results for determining 15 market wines showed that as an important bioactive substance, the resveratrol content has close relationships with brewing methods, varieties of grape and producing areas. The results also showed that it is a convenient, rapid, sensitive and accurate method. It can be used to analyze resveratrols and piceids in other natural samples.