Inhibiting the Aggregation of Aß by Natural Product Molecules.

The abnormal aggregation of Aß has been considered one of the primary causative factors for Alzheimer's disease. Diverse molecular entities have been developed to mitigate the formation of toxic Aß aggregates within the brain by inhibiting Aß aggregation. Recognizing that many FDA-approved drugs are derived from natural products, we present a summary of recent discoveries involving natural product molecules with inhibitory effects on Aß aggregation. By consolidating these findings, our review offers researchers a concise overview of the latest advancements in natural product-based interventions for Alzheimer's disease.

High-throughput sequencing-based analysis of the composition and diversity of the endophyte community in roots of Stellera chamaejasme.

Stellera chamaejasme (S. chamaejasme) is an important medicinal plant with heat-clearing, detoxifying, swelling and anti-inflammatory effects. At the same time, it is also one of the iconic plants of natural grassland degradation in northwest China, playing a key role in the invasion process. Plant endophytes live in healthy plant tissues and can synthesize substances needed for plant growth, induce disease resistance in host plants, and enhance plant resistance to environmental stress. Therefore, studying the root endophytes of S. chamaejasme is of great significance for mining beneficial microbial resources and biological prevention and control of S. chamaejasme. This study used Illumina MiSeq high-throughput sequencing technology to analyze the composition and diversity of endophytes in the roots of S. chamaejasme in different alpine grasslands (BGC, NMC and XGYZ) in Tibet. Research results show that the main phylum of endophytic fungi in the roots of S. chamaejasme in different regions is Ascomycota, and the main phyla of endophytic bacteria are Actinobacteria, Proteobacteria and Firmicutes (Bacteroidota). Overall, the endophyte diversity of the NMC samples was significantly higher than that of the other two sample sites. Principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA) results showed significant differences in the composition of endophytic bacterial and fungal communities among BGC, NMC and XGYZ samples. Co-occurrence network analysis of endophytes showed that there were positive correlations between fungi and some negative correlations between bacteria, and the co-occurrence network of bacteria was more complex than that of fungi. In short, this study provides a vital reference for further exploring and utilizing the endophyte resources of S. chamaejasme and an in-depth understanding of the ecological functions of S. chamaejasme endophytes.

Biased gene expression reveals the contribution of subgenome to altitude adaptation in allopolyploid Isoetes sinensis.

Allopolyploids are believed to inherit the genetic characteristics of its progenitors and exhibit stronger adaptability and vigor. The allotetraploid Isoetes sinensis was formed by the natural hybridization and polyploidization of two diploid progenitors, Isoetes taiwanensis and Isoetes yunguiensis, and was believed to have the potential to adapt to plateau environments. To explore the expression pattern of homoeologous genes and their contributions to altitude adaptation, we transplanted natural allotetraploid I. sinensis (TnTnYnYn) along the altitude gradient for a long-term, and harvested them in summer and winter, respectively. One year after transplanting, it still lived well, even in the extreme environment of the Qinghai-Tibet Plateau. Then, we performed high-throughput RNA sequencing to measure their gene expression level. A total of 7801 homoeologous genes were expressed, among which 5786 were identified as shared expression in different altitudes and seasons. We further found that altitude variations could change the subgenome bias trend of I. sinensis, but season could not. Moreover, the functions of uniquely expressed genes indicated that temperature might be an important restrictive factor during the adaptation process. Through the analysis of DEGs and uniquely expressed genes, we found that Y subgenome provided more contributions to high altitude adaptation than T subgenome. These adaptive traits to high altitude may be inherited from its plateau progenitor I. yunguiensis. Through weighted gene co-expression network analysis, pentatricopeptide repeats gene family and glycerophospholipid metabolism pathway were considered to play important roles in high-altitude adaptation. Totally, this study will enrich our understanding of allopolyploid in environmental adaptation.

The effects of photoperiodism and exposure to bisphenol A on hepatic lipid metabolism in female mice / 中国职业医学

OBJECTIVE: To analyze the effects and the underlying mechanisms of photoperiodism and exposure to bisphenol A(BPA) on hepatic lipid metabolism in female mice. METHODS: A 2×2 factorial design was used. The photoperiod factor was set to fixed and shifted photoperiod, and the BPA factor was set to BPA exposure(BPA group) and non-exposure(control group). Specific pathogen free female C57 BL/6 J mice were randomly divided into four groups: fixed photoperiod control group, shifted photoperiod control group, fixed photoperiod BPA group, and shifted photoperiod BPA group, with eight rats in each group. The fixed photoperiod mice received a 12 ∶12 hours light-dark cycle, and the shifted photoperiod mice experienced reversed light-dark cycle once a week. Mice in BPA group were administered a dose of BPA 50 μg/kg body weigh by gavage, while mice in control group were given a equal volume of corn oil, once per day, five days per week for 12 weeks. The body weight of mice was measured during the experiment. After 12 weeks, all mice in each group were sacrificed. Plasma was collected and the levels of biochemical parameters were measured. Liver tissues were separated for examination of lipid deposition using oil red O and hematoxylin-eosin staining, and plasma triglyceride levels were measured. Real-time fluorescence quantitative polymerase chain reaction was used to detect the mRNA relative expression of genes of fat metabolism in liver tissues. RESULTS: At the end of the experiment, the body weights of mice were higher than that before the experiment(all P<0.05), but there was no statistically significant difference in body weights among the four groups(all P>0.05). The levels of plasma glucose, triglyceride and activity of alanine aminotransferase were higher in shifted photoperiod mice than that in the fixed photoperiod mice(all P<0.05). The plasma aspartate transaminase level was higher in BAP group than that in control group(P<0.01). The area of lipid staining in hepatic tissue was larger in the shifted photoperiod control group, fixed photoperiod BPA group and shifted photoperiod BPA group(all P<0.05), and hepatic lipid droplets aggregation was increased in these three groups compared with the fixed photoperiod control group. The mRNA relative expression of acetyl-coenzyme A carboxylase alpha(Acaca) was higher in the fixed photoperiod BPA and shifted photoperiod control groups(all P<0.05), compared with the fixed photoperiod control group. The relative expression of Acaca mRNA was lower in the shifted photoperiod BPA group than that in the fixed photoperiod BPA group(P<0.05). The mRNA relative expression of sterol regulatory element binding protein(Srebp) 1 and Srebp2 were significantly higher in the BPA group than that in the control group(all P<0.05). CONCLUSION: Both the single shifted photoperiod or BPA exposure can increase hepatic lipid deposition in female mice. The mechanism may be related to up-regulation of the mRNA expression of Acaca, Srebp1 and Srebp2. The shifted photoperiod in combination of BPA exposure has an antagonistic effect on the expression of Acaca mRNA in liver tissues of female mice.

[The application of cation exchange resins in the separation of total flavonoids and alkaloids from seed embryo of Nelumbo nucifera].

OBJECTIVE: To explore the optimal separation condition of the total flavonoids and alkaloids from seed embryo of Nelumbo nucifera. METHODS: Types of cation exchange resins, concentration of extract liquid, solution volume, velocity of adsorption and eluent were evaluated in separating efficiency with measuring the adsorption ratio and eluent ratio. RESULTS: D152 resin was finally chosen. After enrichment and purification with it, the purity of flavonoids and alkaloids were significantly increased by 27.08 and 7.86 times, respectively. CONCLUSION: This method is simple, feasible and suitable for the separation of total flavonoids and alkaloids from seed embryo of Nelumbo nucifera.

Multiple therapeutic effects of adjunctive baicalin therapy in experimental bacterial meningitis.

This study aimed to examine effects of adjunctive baicalin therapy to ampicillin for experimental bacterial meningitis in rabbits. After Escherichia Coli inoculation, mean leukocyte counts, concentrations of protein, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) and lactate in cerebrospinal fluid (CSF), brain water content and mean arterial and intracranial pressures substantially increased in the meningitis group. Ampicillin alone for 5 h markedly exacerbated the enhanced leukocyte counts and protein concentration, and showed no significant effect on the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicalin (7-D-glucuronic acid-5,6-dihydroxyflavone, C(21)H(18)O(11)) completely counteracted ampicillin-induced exacerbation, and further alleviated the enhanced mean leukocyte counts and protein concentration when combined with ampicillin. Adjunctive baicalin also significantly ameliorated the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicillin, as an adjunctive treatment exerted multiple therapeutic effects in experimental bacterial meningitis.

Preparative separation and purification of liensinine, isoliensinine and neferine from seed embryo of Nelumbo nucifera GAERTN using high-speed counter-current chromatography.

A preparative high-speed counter-current chromatography method for separation and purification of liensinine, isoliensinine and neferine from seed embryo of Nelumbo nucifera GAERTN was successfully established by using n-hexane-ethyl acetate-methanol-water (5:8:4:5, v/v, containing 0.5% NH(4)OH) as the two-phase solvent system. From 200 mg of crude extract, 18.4 mg of liensinine, 19.6 mg of isoliensinine and 58.4 mg of neferine were obtained with the purity of 96.8, 95.9, and 98.6%, respectively. The identification of the three alkaloids was performed with (1)H NMR and (13)C NMR.

[Study on the release of oleanolic acid loaded nanocapsules in vitro].

OBJECTIVE: To study the release of oleanolic acid loaded nanocapsules in vitro. METHODS: The rules of drug release in vitro from oleanolic acid loaded nanocapsules were observed by dynamic penetration system and HPLC. RESULTS: The profile curve of oleanolic acid loaded nanocapsules was fit for the Weibull equation. The release t(1/2) of oleanolic acid loaded nanocapsules was about 6.7 times as that of original oleanolic acid. CONCLUSION: Oleanolic acid loaded nanocapsules have obviously sustained effect.

[Comparison of ferulic acid and paeoniflorin between traditional slice decoction and dispensing granule decoction of Siwu Tang].

OBJECTIVE: To compare the contents of ferulic acid and paeoniflorin between traditional slice decoction and dispensing granule decoction of Siwu Tang. METHODS: A HPLC method detected ferulic acid and paeoniflorin with Diamonsil C18 (4.6 mm x 250 mm, 5 microm) column. The column temperature was setup at 35 degrees C and the flow rate was 1 ml/min. The mobile phase for ferulic acid was a mixed solution of MeOH-H2O-0.05% H3PO4 (40:50:10) and the wavelength was 327 nm, while for paeoniflorin was a mixed solution of CH3CN-H2O-0.05% H3PO4 (16:74:10) and the wavelength was 230 nm. RESULTS: The contents of ferulic acid and paeoniflorin in the dispensing granule decoction were 8.91 mg/dose and 83.57 mg/dose, in the traditional slice decoction were 8. 90 mg/dose and 78. 51 mg/dose, and in the dispensing granule decoction from different factories were from 3.36 to 7.67 mg/dose and from 48.13 to 67.52 mg/dose. CONCLUSION: The HPLC chromatotograms are similar in the two forms of Siwu Tang and the contents of ferulic acid and paeoniflorin are equivalent, but discrepant in the dispensing granule decoction from different factories.

[Separation and purification of alkaloids from radix of Zanthoxylum nitidum by macroporous adsorption resin].

OBJECTIVE: To obtain the optimal conditions for separating the alkaloids from the extract of Radix of Zanthoxylum nitidum by selecting appropriate macroporous adsorption resins. METHOD: Eight types of macroporous adsorption were evaluated in separating efficiency with measuring the adsorption ratio and eluting ratio of Alkaloids as indexes. RESULT: The XDA-5 macroporous adsorption resin had the best separating efficiency. After enrichment and purification with it, the product purity and yield of alkaloids were up to 33.25% and 90.15%, respectively. CONCLUSION: This method is simple, feasible and fit for industry production.

[An experimental research on differentiation of mesenchymal stem cells derived from children with spinal muscular atrophy into neuron-like cells].

OBJECTIVE: Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disease. It is characterized by selective loss of spinal cord motor neurons leading to muscle atrophy and is the result of mutation or deletion of the survival motor neuron (SMN) gene. Currently, there are no effective therapies for this disease. Stem cell therapy is a new prospect for SMA patients. This study aimed to investigate whether mesenchymal stem cells (MSCs) can be differentiated into neuron-like cells (NLCs) in SMA patients in order to provide a basis for stem cell therapy for SMA. METHODS: SMA was definitively diagnosed using polymerase chain reaction-restriction fragment length polymerphhism (PCR-RFLP). Two children without SMN1 gene deletion were used as controls. MSCs were isolated and purified from SMA patients and controls, and induced into NLCs by bFGF and baicalin. The NLCs were identified by immunofluourescence staining with NSE and NF monoclonal antibodies. RESULTS: SMA patients showed the deletion of SMN1 exon 7. The morphous and proliferative speed of MSCs between SMA patients and controls were similar. After 6-day induction, MSCs of the two groups displayed similar morphology to that of neurons, with long processes forming extensive networks. NSE and NF, the neuronal markers, were detected in the differentiated NLCs of the two groups. CONCLUSIONS: SMN1 deletion appears not to affect the proliferation and differentiation of MSCs. MSCs of SMA patients can be differentiated into NLCs.

[Separation and purification processes of alkaloids from Lotus plumule with macroporous adsorption resin].

OBJECTIVE: To explore the optimal separation of the alkaloids from Lotus plumule by selecting appropriate macroporous adsorption resins. METHOD: To evaluated the separating efficiency by measuring the adsorption ratio, eluting ratio and the concentration of neferine. RESULT: The LSA -5B macroporous adsorption resin prolided the optimal separating efficiency. The best adsorption capacity was achieved with the following conditions: the concentration of extact liquid was 0. 125 g x mL(-1) (equivalence to raw material), then the resin was washed by water to remove impurity and alkaloids were desorbed by 50% ethanol. CONCLUSION: This method is simple, feasible and suitable for industry production.

[Determination of diltiazem hydrochloride injection by high-performance liquid chromatography].

OBJECTIVE: To establish an high-performance liquid chromatography (HPLC) method for the determination of diltiazem hydrochloride injection. METHODS: The assay was conducted on a NUCLEODUR C18 column with buffer solution (pH6.2)-acetonitrile-methanol (40:30:30) as the mobile phase and the detection wavelength was 240 nm. RESULTS: Diltiazem hydrochloride and relevant substances could be separated under the condition. The linear concentration range of diltiazem hydrochloride was 4 - 200mg/L with the recovery of 100.22% (RSD = 0.37%). CONCLUSION: The method may be used for the determination of diltiazem hydrochloride injection.

[Determination of 3 kinds of components in huanglian jiedu decoction by HPLC under different UV wavelengths].

OBJECTIVE: To determinate 3 kinds of effective components (5 compounds) in Huanglian Jiedu decoction at the same time, namely berberine, palmtine, jatrorrhizine, baicalin and geniposide. METHOD: A HPLC method detected by 3 different UV wavelengths 345 nm for berberine, palmtine and jatrorrhizine, 280 nm for baicalin, 238 nm for geniposide. Diamonsil C18 (4.6 mm x 250 mm, 5 microm) column was used, the mixture of H2O (A) , CH3OH (B) and 0.05% H3PO4 solution (C) as mobile phase in gradient mode. The column temperature was 35 degrees C and the flow rate was 1 mL x min(-1). RESULT: This method was applied to determined 5 compounds in Huanglian Jiedu decoction rapidly and accurately. CONCLUSION: The quality control method is convenient, reasonable and credible for Huanglian Jiedu decoction.