CNTN1 Aggravates Neuroinflammation and Triggers Cognitive Deficits in Male Mice by Boosting Crosstalk between Microglia and Astrocytes.

A wealth of knowledge regarding glial cell-mediated neuroinflammation, which contributes to cognitive deficits in Alzheimer's disease (AD) has emerged in recent years. Contactin 1(CNTN1), a member of the cell adhesion molecule and immunoglobulin supergene family, is centrally involved in axonal growth regulation and is also a key player in inflammation-associated disorders. However, whether CNTN1 plays a role in inflammation-related cognitive deficits and how this process is triggered and orchestrated remain to be fully elucidated. In this study, we examined postmortem brains with AD. CNTN1 immunoreactivity was markedly increased, particularly in the CA3 subregion, as compared with non-AD brains. Furthermore, by applying an adeno-associated virus-based approach to overexpress CNTN1 directly via stereotactic injection in mice, we demonstrated that hippocampal CNTN1 overexpression triggered cognitive deficits detected by novel object-recognition, novel place-recognition and social cognition tests. The mechanisms underlying these cognitive deficits could be attributed to hippocampal microglia and astrocyte activation, which led to aberrant expression of excitatory amino acid transporters (EAAT)1/EAAT2. This resulted in long-term potentiation (LTP) impairment that could be reversed by minocyline, an antibiotic and the best-known inhibitor of microglial activation. Taken together, our results identified Cntn1 as a susceptibility factor involved in regulating cognitive deficits via functional actions in the hippocampus. This factor correlated with microglial activation and triggered astrocyte activation with abnormal EAAT1/EAAT2 expression and LTP impairment. Overall, these findings may significantly advance our understanding of the pathophysiological mechanisms underlying the risk of neuroinflammation related cognitive deficits.

An oligosaccharide marker for rapid authentication of edible bird's nest.

Edible bird's nest (EBN) is a popular and expensive food material. The limited supply and great demand result in the use of adulterants. The authenticity concern is raised due to the lack of appropriate quality markers. Herein, this study aims to provide a specific oligosaccharide marker for rapid EBN authentication. Comparing the benzocaine (ABEE)-labeled saccharide profiles of multiple batches of EBN and adulterants indicates seven unique EBN oligosaccharides. The most abundant one, named BNM001, was selected as a marker and characterized to be Neu5Ac (2-3) Gal by MS and NMR spectra. This new oligosaccharide marker enables a rapid authentication of EBN within 10 min. ABEE labelling of this marker further upgraded the accuracy and sensitivity of the LC-qTOF-MS quantitative analysis. The relative marker content was associated with the quality of EBN products. These results suggest a specific and efficient quality marker for rapid authentication of EBN and related products.

A specific and bioactive polysaccharide marker for Cordyceps.

Cordyceps is one of the most expensive and widely used functional foods. But the authenticity is still a concern due to the lack of appropriate markers. By targeting polysaccharides, this study aimed to develop a specific, and bioactive marker for Cordyceps. Firstly, the results of screening tests of 250 samples by examining both genetic markers and polysaccharide profile showed that a unique polysaccharide fraction (named CCP) was particular to the caterpillar parts. Its potential as a marker was further demonstrated by its ability to induce NO and cytokine production in RAW 264.7 cells. CCP was characterized to be an α-1,4-glucan with a branch at C-6 by the conventional structure analyzing and de novo oligosaccharides sequencing. The content of CCP was closely correlated to the traditional classification criteria. Generally, CCP was a marker that simultaneously enables qualitative and quantitative analysis of Cordyceps.

Amide derivatives of Gallic acid: Design, synthesis and evaluation of inhibitory activities against in vitro α-synuclein aggregation.

Gallic acid (GA), a natural phenolic acid, has received numerous attention because of its anti-oxidative, anti-inflammatory, and anti-cancer activity. More importantly, GA can act as an efficient inhibitor of α-Synuclein (α-Syn) aggregation at early stages. Nevertheless, some evidences suggest that GA is unlikely to cross the blood-brain barrier because of its high hydrophilicity. Hence, GA may not be considered as a promising candidate or entering brain and directly affecting the central nervous system. Accordingly, we have designed and synthesized a series of amide derivatives of GA, some of which possess appropriate lipophilicity and hydrophilicity with LogP (2.09-2.79). Meanwhile, these sheet-like conjugated compounds have good π-electron delocalization and high ability of hydrogen-bond formation. Some compounds have shown better in vitro anti-aggregation activities than GA towards α-Syn, with IC50 down to 0.98 µM. The valid modification strategy of GA is considered an efficient way to discover novel inhibitors of α-Syn aggregation.

An oligosaccharide-marker approach to quantify specific polysaccharides in herbal formula by LC-qTOF-MS: Danggui Buxue Tang, a case study.

Polysaccharides have broad bioactivities and are major components of water decoction of herb formulae. However, the quality control of polysaccharides remains a challenge. Oligosaccharide-fragment approach has been considered in elucidating chemical structures of polysaccharides, but never been used for quantitation. Using reference chemicals and a real sample Danggui Buxue Tang (DBT) in this study, an oligosaccharide-marker approach was established to quantify specific polysaccharides. Firstly, linear relationships between parent polysaccharides and hydrolysis-produced daughter oligosaccharides were verified using reference polysaccharides. Then in case of DBT, two fluorescence-labeled oligosaccharides with high specificity to individual parent polysaccharides were selected as markers. They were easily isolated and identified. Their potential in quantification of parent polysaccharides were satisfactorily validated in terms of linearity (r≥0.99), repeatability (RSD ≤ 8.4 %), and spike recovery (≥80 %). This method could be a promising approach for quality assessment of polysaccharides in herbal formulae.

Oligosaccharide-marker approach for qualitative and quantitative analysis of specific polysaccharide in herb formula by ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry: Dendrobium officinale, a case study.

Qualitative and quantitative analysis of polysaccharides in herb formula remain challenge due to the limited choices of analytical methods concerning the intrinsic characteristics of large molecular mass. Herein, an oligosaccharide-marker approach was newly developed for quality assessment of polysaccharides in herbal materials, using Dendrobium officinale as a case study. This method involved partial acid hydrolysis of D. officinale polysaccharide (DOP) followed by p-aminobenzoic ethyl ester (ABEE) derivatization. Two ABEE-labeled oligosaccharides namely, Te-Man-ABEE and Pen-Man-ABEE, were selected as chemical markers due to their high specificity in herb formula. The linear relationship between the content of these two markers and the content of DOP was then successfully established respectively. The linear relationship was further transformed to that between peak area of chemical markers and DOP content so that chemical markers were not necessary to be isolated for analysis. This linear relationship was systemically validated in terms of precision and accuracy. The results showed that these two oligosaccharide-markers presented a good linear relationship with DOP (R2 ≥ 0.997) in the range of 0.68-16.02 µg. These markers also demonstrated satisfactory precision (RSD < 7.0%), and recovery (91.41%-118.30%) in real sample determination. Additionally, there was no significant difference between the results given by the two chemical markers as the RSD values were not more than 7.0%. While concerning the results given by the oligosaccharide-markers and the previously-published polysaccharide marker, the RSD value was not more than 6.4%. These suggest that the oligosaccharide-marker approach is a simple, quick, and reliable method to qualitatively and quantitatively determine of specific polysaccharide in herb formula.

Anti-oligomerization sheet molecules: Design, synthesis and evaluation of inhibitory activities against α-synuclein aggregation.

Aggregation of α-synuclein (α-Syn) play a key role in the development of Parkinson Disease (PD). One of the effective approaches is to stabilize the native, monomeric protein with suitable molecule ligands. We have designed and synthesized a series of sheet-like conjugated compounds which possess different skeletons and various heteroatoms in the two blocks located at both ends of linker, which have good π-electron delocalization and high ability of hydrogen-bond formation. They have shown anti-aggregation activities in vitro towards α-Syn with IC50 down to 1.09 µM. The molecule is found binding in parallel to the NACore within NAC domain of α-Syn, interfering aggregation of NAC region within different α-Syn monomer, and further inhibiting or slowing down the formation of α-Syn oligomer nuclei at lag phase. The potential inhibitor obtained by our strategy is considered to be highly efficient to inhibit α-Syn aggregation.

Comprehensive comparison of polysaccharides from Ganoderma lucidum and G. sinense: chemical, antitumor, immunomodulating and gut-microbiota modulatory properties.

Both Ganoderma lucidum (GL) and G. sinense (GS) are used as Lingzhi in China. Their functions are assumed to mainly derive from triterpenes and polysaccharides; however, the two species have very different triterpenes profiles, if this was the case, then the bioactivity of these two species should differ. Instead, could the polysaccharides be similar, contributing to the shared therapeutic basis? In this study, two main polysaccharide fractions from different batches of GL and GS were systematically compared by a series of chemical and biological experiments. The results showed that the polysaccharides from two species shared the same structural features in terms of mono-/oligo-saccharide profiles, molecular size, sugar linkages, and IR/NMR spectra. In addition, these polysaccharides showed similar tumor-suppressive activity in mice. Further study on RAW264.7 cells indicated that these polysaccharides exhibited similar inducing effects to macrophages, as evaluated in the phagocytosis function, NO/cytokines production, inhibition against the viability and migration of cancer cells. Mechanistic investigation revealed the identical activation via TLR-4 related MAPK/NF-κB signaling pathway and gut-microbiota modulatory effects. In summary, GL and GS polysaccharides presented similar chemical features, antitumor/immunomodulating activities and mechanism; this establishes polysaccharides as the active principles and supports the official use of both species as Lingzhi.

Preparation and antitumor effects of glaucocalyxin A-γ-cyclodextrin clathrate.

OBJECTIVE: To improve the water solubility of glaucocalyxin A (GLA) by the preparation of glaucocalyxin A γ-cyclodextrin clathrate (GLA-γ-CD) and to investigate the inhibitory effect of GLA-γ-CD on tumor growth in S180 cell xenografts. MATERIALS AND METHODS: GLA-γ-CD, γ-cyclodextrin (γ-CD) and GLA were combined at a mass ratio of 1:1, dissolved in 60°C water by stirring. GLA completely entrapped by the γ-CD was verified by differential thermal analysis, the GLA content was determined. Phase solubility, solubility, and in vitro dissolution rate experiments were performed. The S180 xenograft mouse model was used to observe the tumor inhibitory effects of GLA-γ-CD and GLA, and the TUNEL assay was used to detect differences in their rates of tumor cell apoptosis induction. RESULTS: After combination with γ-CD, the solubility of GLA-γ-CD was 21.78-fold greater than that of GLA. The in vitro dissolution rate of GLA-γ-CD was significantly greater than that of GLA, and reached more than 90% in 20 min. Furthermore, GLA-γ-CD was more effective than GLA as an inhibitor of S180 tumor cells; the inhibitory rate of the high-dose group reached 57.26%, which was 54.11% greater than the inhibitory rate of the GLA group at the same dose. In addition, GLA-γ-CD induced tumor cell apoptosis more effectively than did GLA. CONCLUSION: The water solubility of GLA significantly increased in combination with γ-CD resulting in the production of GLA-γ-CD. Furthermore, GLA-γ-CD was more effective than GLA as an inducer of S180 tumor cell apoptosis and an inhibitor of tumor growth.

Isolation and identification of a new ent-kaurane diterpenoid from the leaves of Isodon japonica.

A new ent-kaurane diterpenoid, 3α, 14ß, 16α-trihydroxy-ent-kaurane (1), together with seven known diterpenoids (2-8), was isolated from the leaves of Isodon japonica. Their structures were elucidated by spectroscopic methods, including 1D and 2D NMR experiments, IR, HR-ESI-MS and X-ray crystallographic analysis.

Isolation, structural elucidation, and cytotoxicity of three new ent-kaurane diterpenoids from Isodon japonica var. glaucocalyx.

Three new ENT-kaurane diterpenoids, glaucocalyxin H ( 1), glaucocalyxin I ( 2), and glaucocalyxin J ( 3), together with four known diterpenoids ( 4- 7), were isolated from the leaves of Isodon japonica Hara var. glaucocalyx. Their structures were elucidated by spectroscopic analysis, and the structures of compounds 2 and 3 were further confirmed by X-ray crystallographic analysis. Compounds 1, 4, and 5 were evaluated for their cytotoxicity IN VITRO against CE-1, U87, A-549, MCF-7, Hela, K-562, and HepG-2 human tumor cell lines. Compound 1 showed potent inhibitory activities against six tumor cell lines with IC (50) values ranging from 1.86-10.95 µM, and compounds 4 and 5 exhibited significant selective cytotoxicity on seven tumor cell lines.

3ß,11α-Dihy-droxy-12-ursen-3-yl palmitate.

In the title compound, C(46)H(80)O(3), a natural ursane-type triperpenoid, four of the five six-membered rings adopt chair conformations; the fifth, which has a C=C double bond, adopts an approximate half-boat conformation. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, forming chains along [010].

An ent-kaurane diterpenoid from Isodon japonica var. glaucocalyx.

The title compound, 14ß-acet-oxy-7α-hydr-oxy-ent-kaur-16-ene-3,15-dione or glaucocalyxin B, C(22)H(30)O(5), a natural ent-kaurane diterpenoid, is composed of four rings with the expected cis and trans ring junctions. In the crystal structure, there are two mol-ecules in the asymmetric unit related by a noncrystallographic twofold screw axis, and ring A is disordered [ratio occupancies 0.829 (19):0.171 (19)], such that both chair and boat conformations are present, but with the boat conformation as the major component. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds.

Cytotoxic ent-kaurane diterpenoids from Isodon macrophyllus.

Two new ent-kaurane diterpenoids, dayecrystals D-E (1-2), together with nine known compounds, isojaponin A (3), rabdosin A (4), lushanrubescensin J (5), wikstroemioidin B (6), maoyecrystal C (7), rabdosin B (8), isodonal (9), shikokianin (10), and effusanin A (11), were isolated from the leaves of Isodon macrophyllus. The structures of the new compounds were elucidated using 1D and 2D NMR spectroscopy. The (13)C-NMR spectral data of compound 4 are reported for the first time. All of the compounds were tested for their cytotoxicities against DU145 and LoVo human tumor cells. Compounds 4, 10, and 11 showed inhibitory effects on DU145 cells with IC(50) values 5.90, 4.24, and 3.16 microM, and LoVo cells with IC(50) values 14.20, 17.55, and 3.02 microM, respectively.

Two novel ent-kauranoid diterpenoids from Isodon japonica leaves.

Two novel ent-kaurane diterpenoids, taihangjaponicain A (1), and taihangjaponicain B ( 2), and nine known diterpenoids, epinodosin (3), oridonin (4), epinodosinol (5), lasiokaurin ( 6), 1alpha- O-beta- D-glucopyranosylenmenol (7), lasiodonin (8), rabdosichuanin D ( 9), shikokianin (10) and rabdoternin A (11) were isolated from I. japonica leaves. The structures of the two new compounds were elucidated using 1-D and 2-D NMR spectroscopy. Compounds 1 and 3 - 11 were tested against HL-60, HO-8910 and A-549 human tumor cells. Compounds 4, 6 and 10 showed significant cytotoxicity against HL-60 cells with IC (50) values of 4.6, 2.0 and 3.4 microM, respectively, and against A-549 cells with IC (50) values of 17.5, 11.4 and 18.8 microM, respectively. Compound 6 exhibited moderate cytotoxicity against HO-8910 cells with an IC (50) value of 17.9 microM.