Mechanism interpretation of Guhan Yangshengjing for protection against Alzheimer's disease by network pharmacology and molecular docking.

ETHNOPHARMACOLOGICAL RELEVANCE: Guhan Yangshengjing (GHYSJ) is an effective prescription for delaying progression of Alzheimer's disease (AD) based on the ancient Chinese medical classics excavated from Mawangdui Han Tomb. Comprising a combination of eleven traditional Chinese herbs, the precise protective mechanism through which GHYSJ acts on AD progression remains unclear and has significant implications for the development of new drugs to treat AD. AIM OF THE STUDY: To investigate the mechanism of GHYSJ in the treatment of AD through network pharmacology and validate the results through in vitro experiments. MATERIALS AND METHODS: Chemical composition-target-pathway network and protein-protein interaction network were constructed by network pharmacology to predict the potential targets of GHYSJ for the treatment of AD. The interaction relationship between active ingredients and targets was verified by molecular docking and molecular force. Furthermore, the chemical constituents of GHYSJ were analyzed by LC-MS and HPLC, the effects of GHYSJ on animal tissues were analyzed by H&E staining. An Aß-induced SH-SY5Y cellular model was established to validate the core pathways and targets predicted by network pharmacology and molecular docking. RESULTS: The results of the network pharmacology analysis revealed a total of 155 bioactive compounds capable of crossing the blood-brain barrier and interacting with 677 targets, among which 293 targets specifically associated with AD, which mainly participated in and regulated the amyloid aggregation pathway and PI3K/Akt signaling pathway, thereby treating AD. In addition, molecular docking analysis revealed a robust binding affinity between the principal bioactive constituents of GHYSJ and crucial targets implicated in AD. Our findings were further substantiated by in vitro experiments, which demonstrated that Liquiritigenin and Ginsenosides Rh4, crucial constituents of GHYSJ, as well as GHYSJ pharmaceutic serum, exhibited a significant down-regulation of BACE1 expression in Aß-induced damaged SH-SY5Y cells. This study provides valuable data and theoretical underpinning for the potential therapeutic application of GHYSJ in the treatment of AD and secondary development of GHYSJ prescription. CONCLUSION: Through network pharmacology, molecular docking, LC-MS, and cellular experiments, GHYSJ was initially confirmed to delay the progression of AD by regulating the expression of BACE1 in Amyloid aggregation pathway. Our observations provided valuable data and theoretical underpinning for the potential therapeutic application of GHYSJ in the treatment of AD.

Real-Time Determination of Intracellular cAMP Reveals Functional Coupling of Gs Protein to the Melatonin MT1 Receptor.

Melatonin is a neuroendocrine hormone that regulates the circadian rhythm and many other physiological processes. Its functions are primarily exerted through two subtypes of human melatonin receptors, termed melatonin type-1 (MT1) and type-2 (MT2) receptors. Both MT1 and MT2 receptors are generally classified as Gi-coupled receptors owing to their well-recognized ability to inhibit cAMP accumulation in cells. However, it remains an enigma as to why melatonin stimulates cAMP production in a number of cell types that express the MT1 receptor. To address if MT1 can dually couple to Gs and Gi proteins, we employed a highly sensitive luminescent biosensor (GloSensorTM) to monitor the real-time changes in the intracellular cAMP level in intact live HEK293 cells that express MT1 and/or MT2. Our results demonstrate that the activation of MT1, but not MT2, leads to a robust enhancement on the forskolin-stimulated cAMP formation. In contrast, the activation of either MT1 or MT2 inhibited cAMP synthesis driven by the activation of the Gs-coupled ß2-adrenergic receptor, which is consistent with a typical Gi-mediated response. The co-expression of MT1 with Gs enabled melatonin itself to stimulate cAMP production, indicating a productive coupling between MT1 and Gs. The possible existence of a MT1-Gs complex was supported through molecular modeling as the predicted complex exhibited structural and thermodynamic characteristics that are comparable to that of MT1-Gi. Taken together, our data reveal that MT1, but not MT2, can dually couple to Gs and Gi proteins, thereby enabling the bi-directional regulation of adenylyl cyclase to differentially modulate cAMP levels in cells that express different complements of MT1, MT2, and G proteins.

Multi-target regulatory mechanism of Yang Xin Tang - a traditional Chinese medicine against dementia.

BACKGROUND: Yang Xin Tang (YXT) is a traditional Chinese herbal preparation which has been reported to improve cognitive function and memory in patients with dementia. As the underlying mechanism of action of YXT has not been elucidated, we examined the effects of YXT and its major herbal components in regulating gene transcription and molecular targets related to Alzheimer's disease (AD). METHODS: Aqueous and ethanol extracts of YXT and selected herbal components were prepared and validated by standard methods. A series of biochemical and cellular assays were employed to assess the ability of the herbal extracts to inhibit acetylcholinesterase, reduce ß-amyloid aggregation, stimulate the differentiation of neural progenitor cells, suppress cyclooxygenase, and protect neurons against ß-amyloid or N-methyl-D-aspartate-induced cytotoxicity. The effects of YXT on multiple molecular targets were further corroborated by a panel of nine reporter gene assays. RESULTS: Extracts of YXT and two of its constituent herbs, Poria cocos and Poria Sclerotium pararadicis, significantly inhibited ß-amyloid aggregation and ß-amyloid-induced cytotoxicity. A protective effect of the YXT extract was similarly observed against N-methyl-D-aspartate-induced cytotoxicity in primary neurons, and this activity was shared by extracts of Radix Astragali and Rhizoma Chuanxiong. Although the YXT extract was ineffective, extracts of Poria cocos, Poria Sclerotium pararadicis and Radix Polygalae inhibited acetylcholine esterase, with the latter also capable of upregulating choline acetyltransferase. YXT and its components significantly inhibited the activities of the pro-inflammatory cyclooxygenases. Additionally, extracts of YXT and several of its constituent herbs significantly stimulated the phosphorylation of extracellular signal-regulated kinases and cAMP-responsive element binding protein, two molecular targets involved in learning and memory, as well as in the regulation of neurogenesis. CONCLUSIONS: Several constituents of YXT possess multiple regulatory effects on known therapeutic targets of AD that range from ß-amyloid to acetylcholinesterase. The demonstrated neuroprotective and neurogenic actions of YXT lend credence to its use as an alternative medicine for treating AD.

[A new isoflavone from Dalbergia odorifera and inhibitory activity of its tyrosinase].

Twelve flavonoids were isolated and purified from the ethyl acetate fraction of 95% ethanol extract of Dalbergia odorifera by heat reflux extraction, solvent extraction, recrystallization, normal phase silica gel, Sephadex LH-20, MCI gel and HPLC methods. The structures were identified with multiple spectroscopic methods, including 1 D-NMR, 2 D-NMR and MS. The compounds were identified as 6,7,8-trimethoxy-5,4'-dihydroxy isoflavone(1), medicarpin(2), 7,2'-dihydroxy-4'-methoxy-isoflavanol(3), biochanin A(4), prunetin(5), genistein(6), pratensein(7), 3-(4-hydroxyphenyl)-6-isopentenyl-7-methoxy-4H-chromen-4-one(8), tectorigenin(9), irisolidone(10), vestitol(11), and formononetin(12). Compound 1 was a new isoflavone, and compound 8 was isolated from D. odorifera for the first time. The results showed that compounds 1-3 had inhibitory effects on tyrosinase, with inhibition rates of 35.58%, 38.63% and 51.34% at the concentration of 1.0 mmol·L~(-1), respectively.

Citizen science as a tool for enhancing recreation research in protected areas: Applications and opportunities.

As the popularity of nature-based recreation and tourism grows, protected area (PA) managers around the world are faced with escalating monitoring and management challenges across spatial and temporal scales. Citizen science, an emerging research approach which involves active public participation and collaboration with scientists in the scientific process, is an innovative tool that could help managers address these challenges. This study applied the Preferred Reporting Items for Systematic Review Recommendations (PRISMA) protocol to review published studies that utilized citizen science methods in recreation research, examining the extent and nature of such applications and identifying future opportunities. We identified 20 peer-reviewed journal articles from the Web of Science, most of which were published since 2015. These studies utilized different citizen science approaches to examine recreation patterns, behaviors, and impacts in terrestrial and marine PAs. We found that citizen science was used most often in marine PAs, with specialized recreationists (e.g., SCUBA divers) as the most frequent contributors. The types of volunteers recruited differed by their sources (i.e., general public, recreation specialists, and organizational affiliates) and roles (i.e., volunteers as agents of data collection and volunteers as research subjects), with innovative technology (e.g., participatory GIS) creating new engagement opportunities. Despite these benefits, the accuracy and reliability of citizen science data remain important considerations for managers. Our review demonstrates how citizen science can inform management and enhance public participation in PA stewardship activities, and it reveals the need for more research to explore applications of citizen science in different recreation contexts.

Picture naming in bilingual and monolingual Chinese speakers: Capturing similarity and variability.

Picture-naming latency differs across languages in bilingual speakers. We compared the effects of key psycholinguistic variables on picture naming among two groups of Chinese bilingual speakers and Mandarin monolingual speakers. First, we asked bilingual and monolingual speakers to estimate the age of acquisition, familiarity, visual complexity, name agreement, and imageability of a set of object and action pictures in Mandarin and Cantonese. Next, we recruited 60 Cantonese-English speakers, 50 Mandarin-Cantonese bilingual speakers, and 30 monolingual speakers who named the object and action pictures in Cantonese and Mandarin, respectively. We observed variability in the effects of item-level characteristics among groups, suggesting an interaction between item-level and individual-level characteristics as predicted. This variability was higher in bilingual speakers who spoke similar languages (Mandarin-Cantonese) in comparison to those speaking more distant languages (Cantonese-English). Our results suggest that monolingual norms and bilingual norms capture the same amount of variability; however, grammatical class interactions with other variables are explained differentially by the bilingual and monolingual norms. We discuss the implications of our findings in terms of norming studies for timed picture naming and effects of bilingualism on language processing.

Phytochemical study of Ligularia subspicata and valuation of its anti-inflammatory activity.

This report illustrated isolation and identification of 42 compounds comprising five (spicatainoids A-E) undescribed eremophilanolide type sesquiterpenoids and one undescribed nor-eremophilane (spicatainoid F) from Ligularia subspicata.. Among all the isolated new compounds, 4 is reported as the first enantiomeric form of novel eremophilanolide type sesquiterpenoid. Comprehensive analysis of HRESIMS, 1D/2D NMR, experimental circular dichroism (CD), calculated ECD analysis, and X-ray crystallographic (XRD) analysis validated the complete configuration and confirmation of these isolated compounds. All the isolated compounds were tested for the anti-inflammatory potential by measuring the amount of nitric oxide production. Among the tested compounds, 4 was the most effective with 90% NO-inhibition activity. Compounds 1, 2, 3, 9, 10 18, 29, 34, 35 exhibited moderate inhibitory effects against the production of NO, while other compounds displayed no activity even at the concentration of 50 µM. Additionally, compounds 1, 3 and 4 presented moderate anti-inflammatory activity by inhibiting the release of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in LPS-stimulated N9 cells. The IC50 values of compounds 1, 3 and 4 were calculated 39.6 ± 2.7, 42.5 ± 3.8 and 27.60 ± 1.9 µΜ.