Tai Chi Improves Cognitive Function of Dementia Patients: A Systematic Review and Meta-analysis.

Background: Studies show that Tai Chi, a traditional Chinese mind-body exercise, has the potential to improve cognitive and physical function among the elderly. However, debates continue about its effectiveness among persons with dementia (PWD). Primary study objective: This study assessed the effectiveness of Tai Chi in improving cognitive, physical, and emotional function among PWDs. Methods: We conducted a systematic review of research on online databases (MEDLINE, EMBASE, Pubmed, and Cochrane Library) published up to April 2021. Relevant randomized clinical trials (RCTs) were reviewed and analyzed. A random-effect model was used to evaluate the pooled mean difference values. Intervention: The individuals in the intervention group practiced Tai Chi exercises in addition to their regular care, while the individuals in the control group continued their usual care. Primary Outcome Measures: We focus on three outcome measures: the Mini-mental State Examination (MMSE), Timed Up and Go (TUG), and Geriatric Depression Scale (GDS) scores. Results: Seven studies (N = 616) were included in the meta-analysis. Our results show that Tai Chi can improve cognitive function in PWDs (P = .007, SMD = 0.27; 95% CI, 0.08 to 0.47). However, Tai Chi might not improve the TUG (P = .25, SMD = -0.64; 95% CI, -1.74 to 0.46) and GDS (P = .61; SMD = -0.36; 95% CI -2.00 to 1.17) functions. Conclusions: The results suggest that Tai Chi can help improve cognitive function among PWDs, but it has no physical and emotional benefits as assessed using the TUG and GDS scales, respectively.

Structural Characterization and Antioxidant Activity of Polysaccharides from Athyrium multidentatum (Doll.) Ching in d-Galactose-Induced Aging Mice via PI3K/AKT Pathway.

The purpose of this study was to characterize the polysaccharides from Athyrium multidentatum (Doll.) Ching (AMC) rhizome and explore the protective mechanism against d-galactose-induced oxidative stress in aging mice. METHODS: A series of experiments, including molecular weight, monosaccharide composition, Fourier transform infrared (FT-IR) spectroscopy, and 1H nuclear magnetic resonance (1H NMR) spectroscopy were carried out to characterize AMC polysaccharides. The mechanism was investigated exploring d-galactose-induced aging mouse model. Quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) and western blotting assays were performed to assess the gene and protein expression in liver. KEY FINDINGS: Our results showed that AMC polysaccharides were mainly composed of mannose (Man), rhamnose (Rha), glucuronic acid (Glc A), glucose (Glc), galactose (Gal), arabinose (Ara), and fucose (Fuc) in a molar ratio of 0.077:0.088:0.09:1:0.375:0.354:0.04 with a molecular weight of 33203 Da (Mw). AMC polysaccharides strikingly reversed d-galactose-induced changes in mice, including upregulated phosphatidylinositol 3-kinase (PI3K), Akt, nuclear factor-erythroid 2-related factor 2 (Nrf2), forkhead box O3a (FOXO3a), and hemeoxygenase-1 (HO-1) mRNA expression, raised Bcl-2/Bax ratio, downregulated caspase-3 mRNA expression, enhanced Akt, phosphorylation of Akt (p-Akt), Nrf2 and HO-1 protein expression, decreased caspase-3, and Bax protein expression. CONCLUSION: AMC polysaccharides attenuated d-galactose-induced oxidative stress and cell apoptosis by activating the PI3K/AKT pathway, which might in part contributed to their anti-aging activity.

Striatisporolide A, a butenolide metabolite from Athyrium multidentatum (Doll.) Ching, as a potential antibacterial agent.

The present study aimed to investigate the antibacterial activity of striatisporolide A (SA) against Escherichia coli (E. coli) and the underlying mechanism. Antibacterial activity was evaluated according to the inhibitory rate and zone of inhibition. The antibacterial mechanism was investigated by analyzing alkaline phosphatase (AKP) activity and ATP leakage, protein expression, cell morphology and intracellular alterations in E. coli. The results demonstrated that SA exerted bacteriostatic effects on E. coli in vitro. AKP activity and ATP leakage analysis revealed that SA damaged the cell wall and cell membrane of E. coli. SDS­PAGE analysis indicated that SA notably altered the level of 10 and 35 kDa proteins. Scanning electron microscopy and transmission electron microscopy analyses revealed marked alterations in the morphology and ultrastructure of E. coli following treatment with SA. The mechanism underlying the antimicrobial effects of SA against E. coli may be attributed to its actions of disrupting the cell membrane and cell wall and regulation of protein level. The findings of the present study provide novel insight into the antimicrobial activity of SA as a potential natural antibacterial agent.

Tyrosinase immobilization on aminated magnetic nanoparticles by physical adsorption combined with covalent crosslinking with improved catalytic activity, reusability and storage stability.

In the present study, the immobilization method of physical adsorption combined with covalent crosslinking was developed to avoid the shortcomings of both the noncovalent and covalent coupling methods. For the first time, tyrosinase (TYR) was immobilized on the surface of aminated magnetic nanoparticles (Fe3O4-NH2) by the developed method. TYR was firstly adsorbed on the surface of Fe3O4-NH2 by electrostatic interaction, and then by covalent crosslinking with glutaraldehyde (GA), TYR was firmly immobilized on the supports. The immobilized TYR showed enhanced pH and temperature endurances at the optimum pH of 7.0 and temperature of 35 °C. TYR reusability was significantly improved after immobilization and it retained 61.4 ±â€¯2.3% of its initial activity after 5 repeated cycles. Immobilized TYR also showed improved storage stability (73.2 ±â€¯1.1% after 30 days of storage at 4 °C). In addition, the immobilized TYR showed a higher biological affinity to substrate owing to the stabilization of TYR in its active conformation by electrostatic interaction prior to covalent crosslinking. Finally, the immobilized TYR was used to screen of enzyme inhibitors from 11 traditional Chinese medicines (TCMs) to validate whether this method can be used for enzyme inhibitor screening or not.

α-Glucosidase immobilization on chitosan-enriched magnetic composites for enzyme inhibitors screening.

In the present study, the chitosan-enriched magnetic composites (MCCs) were prepared by a novel and simple embedding method for the immobilization of α-glucosidase (α-Glu). The immobilized α-Glu could be easily separated from the reaction mixture under an external magnetic field owing to the magnetic support. With the MCCs-immobilized α-Glu, enzyme activity and stability were studied, and enzyme inhibitors were screened from traditional Chinese medicines (TCMs) and vegetables combined with capillary electrophoresis (CE). The MCCs-immobilized α-Glu exhibited enhanced pH and temperature tolerance with unchanged optimum pH and temperature of 4.0 and 60°C comparing with free α-Glu. Reusability of the immobilized α-Glu was significantly improved after immobilization, and it retained 62.2% of its initial activity after 10 repeated cycles. Immobilized α-Glu also showed improved storage stability (84.3±1.2% after 35days of storage at 4°C). The kinetic parameter Km for immobilized α-Glu was calculated to be 0.81mM and the affinity of enzyme towards its substrate was reduced after immobilization. Finally, immobilized α-Glu was used to screen enzyme inhibitors from the extracts of TCMs and vegetables. The enhanced pH and temperature tolerance, improved reusability and storage stability of MCCs-immobilized α-Glu make it a promising candidate for biotechnological applications.

Kinetics and inhibition study of tyrosinase by pressure mediated microanalysis.

In the present study, pressure mediated microanalysis (PMMA), a fast, convenient and efficient capillary electrophoresis (CE) method was developed for studying enzyme kinetics of tyrosinase and inhibition kinetics of kojic acid, a model inhibitor of tyrosinase. The enzymatic reaction conditions and CE conditions were optimized in order to obtain high enzyme activity and short analysis time. By PMMA, only the product could be detected at 475 nm, and no voltage was applied to separate the product from the reaction mixture thus greatly simplifying the optimization procedure. The spectrophotometric assay and electrophoretically mediated microanalysis (EMMA) were also performed to validate the developed method. With the present method, the Michaelis-Menten constant (Km) was calculated to be 1.347 mM for tyrosinase. The inhibition constant of kojic acid to free tyrosinase (KI) and kojic acid to tyrosinase/L-DOPA complex (KIS) were calculated to be 36.64 and 74.35 µM, respectively, and the half-maximal inhibitory concentration (IC50) was determined to be 46.64 µM for kojic acid. The developed method is fast and convenient for studying enzyme kinetics, inhibition kinetics and further screening enzyme inhibitors.

Screening of enzyme inhibitors from traditional Chinese medicine by magnetic immobilized α-glucosidase coupled with capillary electrophoresis.

As the close correlation between α-glucosidase inhibitors and the treatment of diabetes, in combination with capillary electrophoresis (CE), a method was developed to screen α-glucosidase inhibitors from traditional Chinese medicines (TCMs) by immobilizing α-glucosidase on magnetic nanoparticles. Such a magnetic immobilization would be beneficial for enzyme reusability, stability and separation. In this work, Fe3O4 nanoparticles were synthesized by solvothermal method. And the prepared nanoparticles were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), size and zeta potential analysis. With the modification of chitosan (CS) and glutaraldehyde (GA), α-glucosidase was successfully immobilized on the magnetic nanoparticles. The pH and temperature endurance, storage stability and reusability of the immobilized α-glucosidase were studied and compared with those of the free one. With the magnetic immobilized α-glucosidase, the Michaelis-Menten constant (Km) was calculated to be 0.85mM, and the inhibition constant (Ki) and half-maximal inhibitory concentration (IC50) for acarbose were determined to be 7.37 and 13.69µM, respectively. Finally, the developed method was applied to screen α-glucosidase inhibitors from 18 TCMs.

Cytoproliferative and Cytoprotective Effects of Striatisporolide A Isolated from Rhizomes of Athyrium multidentatum (Doell.) Ching on Human Umbilical Vein Endothelial Cells.

OBJECTIVES: The aim of this study was to investigate the proliferative and protective effects of striatisporolide A (SA) obtained from the rhizomes of Athyrium multidentatum (Doell.) Ching on human umbilical vein endothelial cells (HUVECs). METHODS: Cell viability was measured by the MTT method. Cell apoptosis was determined by flow cytometry. Intracellular ROS was measured by the 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probe. RESULTS: The viability rate in cells treated with 100 µM SA alone was increased to 128.72% ± 0.19% and showed a significant difference compared with the control group (p < 0.05). Meanwhile, SA augmented the cell viabilities in H2O2-treated HUVECs, and the cell viability was enhanced to 56.94% ± 0.13% (p < 0.01) when pre-incubated with 50 µM SA. The cell apoptosis rates were reduced to 2.17% ± 0.20% (p < 0.05) and 3.1% ± 0.34% (p < 0.01), respectively, after treatment with SA alone or SA/H2O2. SA inhibited the overproduction of reactive oxygen species (ROS) in HUVECs induced by H2O2 and the fluorescent intensity was abated to 9.47 ± 0.61 after pre-incubated with 100 µM SA. CONCLUSIONS: The biological activities of SA were explored for the first time. Our results stated that SA exhibited significant cytoproliferative and minor cytoprotective effects on HUVECs. We presume that the mechanisms of the proliferation and protection actions of SA involve interference with the generation of ROS and the cell apoptosis. These findings provide a new perspective on the biological potential of butenolides.

In vitro antioxidant activity of Bombax malabaricum flower extracts.

CONTEXT: Bombax malabaricum DC. (Bombacaceae) is a traditional Chinese herbal medicine used for the treatment of inflammatory conditions, diarrhea, fever, chronic inflammation, catarrhal affection, and as a diuretic. However, little information is available about its antioxidative activity. OBJECTIVE: Water, 50% ethanol, and 80% acetone extracts from flowers of B. malabaricum were investigated for their in vitro antioxidant activity in this article for the first time. Then the relationships between antioxidant activity measured by different methods and total phenolic content (TPC) and total flavonoid content (TFC) were established. MATERIALS AND METHODS: The antioxidant activities of extracts from B. malabaricum flower were investigated including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, oxygen radical absorbance capacity (ORAC), reducing power, and inhibition on phosphatidylcholine liposome peroxidation. RESULTS: Results showed that all the extracts possessed remarkable antioxidant capacity compared with ascorbic or gallic acids. Total antioxidant activities evaluated by ORAC assay of different extracts ranged from 700.03 to 1482.46 µmol Trolox equivalents/g. The highest TPC of 130.38 mg gallic acid equivalents (GAE)/g was observed in 80% acetone extract, whereas the lowest TPC of 57.09 mg GAE/g was obtained in the water extract. Furthermore, TFC exhibited significant (P < 0.05) positive correlations with DPPH radical-scavenging activity, ORAC, and reducing power. DISCUSSION AND CONCLUSION: These findings demonstrate that the flowers of B. malabaricum have excellent antioxidant activities and thus might be a potential source of natural antioxidants.

Biological control experiment of excess propagation of Cyclops for drinking water security.

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish (10 g), and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.