Bioassay-Guided Isolated Compounds from Morinda officinalis Inhibit Alzheimer's Disease Pathologies

In silico and in vivo study of anti-inflammatory activity of Morinda longissima (Rubiaceae) extract and phytochemicals for treatment of inflammation-mediated diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally, the plant Morinda longissima Y.Z.Ruan (Rubiaceae) is used by ethnic people in Vietnam for the treatment of liver diseases and hepatitis.

AIM OF THE STUDY

The study was designed to assess the efficacy of the 95% ethanolic extract of Morinda longissima roots (MLE) in experimental immune inflammation. The phytochemical variation of root extract and the chemical structures of natural compounds were also investigated using HPLC-DAD-HR-MS analysis.

MATERIALS AND METHODS

Three different doses (100, 200, and 300 mg/kg b.w.) of MLE were chosen to determine anti-inflammatory activity. The mice were given orally extracts and monitored their behavior and mortality for 14 days to evaluate acute toxicity. The volume of the paw and the histopathological evaluation were carried out. The polyphenolic phytoconstituents of MLE extract were identified using LC/MS analysis. The anti-inflammatory efficacy in silico and molecular docking simulations of these natural products were evaluated based on their cyclooxygenase (COX)-1 and 2 inhibitory effects.

RESULTS

This investigation showed the 95% ethanolic extract of Morinda longissima roots was found non-toxic up to 2000 mg/kg dose level in an acute study, neither showed mortality nor treatment-related signs of toxicity in mice. Eight anthraquinones and anthraquinone glycosides of Morinda longissima roots were identified by HPLC-DAD-HR-MS analysis. In the in vivo experiments, MLE was found to possess powerful anti-inflammatory activities in comparison with diclofenac sodium. The highest anti-inflammatory activity of MLE in mice was observed at a dose of 300 mg/kg body weight. The in silico analysis showed that seven out the eight anthraquinones and anthraquinone glycosides possess a selectivity index RCOX-2/COX-1 lower than 1, indicating that these compounds are selective against the COX-2 enzyme in the following the order: rubiadin-3-methyl ether < morindone morindone-6-methyl ether < morindone-5-methyl ether < damnacanthol < rubiadin < damnacanthol-3-O-β-primeveroside. The natural compounds with the best selectivity against the COX-2 enzyme are quercetin (9), rubiadin-3-methyl ether (7), and morindone (4), with RCOX2/COX1 ratios of 0.02, 0.03, and 0.19, respectively. When combined with the COX-2 protein in the MD research, quercetin and rubiadin-3-methyl ether greatly stabilized the backbone proteins and ligands.

CONCLUSION

In conclusion, the anthraquinones and ethanolic extract of Morinda longissima roots may help fight COX-2 inflammation. To develop novel treatments for inflammatory disorders linked to this one, these chemicals should be investigated more in the future.

Anti-inflammatory monoterpenes from morinda (Morinda officinalis How.)

Morinda (Morinda officinalis How.) is widely consumed as a functional food owing to its potential to promote health. This study investigated the anti-inflammatory phytochemicals of morinda and isolated 30 monoterpenes, including 6 undescribed iridoids (1, 6, 9-11 and 25), 2 undescribed acyclic monoterpenoids (28, 29), a known acyclic monoterpenoid and 21 known iridoids. Their chemical and stereo-structures were elucidated based on HR-ESI-MS, NMR, 13C-NMR calculations, ECD data and ECD calculations. Notably, compounds 11, 12 and 20 exerted pronounced inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages, with IC50 values of 28.51 ± 1.70, 25.45 ± 4.17 and 29.17 ± 3.71 μM respectively (indomethacin, IC50 of 33.68 ± 2.19 μM). The same compounds exert anti-inflammatory effects by blocking nuclear translocation of nuclear factor κ-B, and down-regulating the expression of inflammatory cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-1β and interleukin-6 at mRNA and protein levels in a dose-dependent manner. These results suggest that moderate consumption of morinda helps prevent and reduce the occurrence of inflammatory-related diseases.

Neuroprotective effect of the traditional decoction Tian-Si-Yin against Alzheimer's disease via suppression of neuroinflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease among old adults. As a traditional Chinese medicine, the herbal decoction Tian-Si-Yin consists of Morinda officinalis How. and Cuscuta chinensis Lam., which has been widely used to nourish kidney. Interestingly, Tian-Si-Yin has also been used to treat dementia, depression and other neurological conditions. However, its therapeutic potential for neurodegenerative diseases such as AD and the underlying mechanisms remain unclear.

AIM OF THE STUDY

To evaluate the therapeutic effect of the herbal formula Tian-Si-Yin against AD and to explore the underlying mechanisms.

MATERIALS AND METHODS

The N2a cells treated with amyloid β (Aβ) peptide or overexpressing amyloid precursor protein (APP) were used to establish cellular models of AD. The in vivo anti-AD effects were evaluated by using Caenorhabditis elegans and 3 × Tg-AD mouse models. Tian-Si-Yin was orally administered to the mice for 8 weeks at a dose of 10, 15 or 20 mg/kg/day, respectively. Its protective role on memory deficits of mice was examined using the Morris water maze and fear conditioning tests. Network pharmacology, proteomic analysis and ultra-high performance liquid chromatography-mass spectrometry/mass spectrometry (UHPLC-MS/MS) were used to explore the underlying molecular mechanisms, which were further investigated by Western blotting and immunohistochemistry.

RESULTS

Tian-Si-Yin was shown to improve cell viability of Aβ-treated N2a cells and APP-expressing N2a-APP cells. Tian-Si-Yin was also found to reduce ROS level and extend lifespan of transgenic AD-like C. elegans model. Oral administration of Tian-Si-Yin at medium dose was able to effectively rescue memory impairment in 3 × Tg mice. Tian-Si-Yin was further shown to suppress neuroinflammation by inhibition of glia cell activation and downregulation of inflammatory cytokines, diminishing tau phosphoralytion and Aβ deposition in the mice. Using UHPLC-MS/MS and network pharmacology technologies, 17 phytochemicals from 68 components of Tian-Si-Yin were identified as potential anti-AD components. MAPK1, BRAF, TTR and Fyn were identified as anti-AD targets of Tian-Si-Yin from network pharmacology and mass spectrum.

CONCLUSIONS

This study has established the protective effect of Tian-Si-Yin against AD and demonstrates that Tian-Si-Yin is capable of improving Aβ level, tau pathology and synaptic disorder by regulating inflammatory response.

Selenium Nanoparticles Based on Morinda officinalis Polysaccharides: Characterization, Anti-Cancer Activities, and Immune-Enhancing Activities Evaluation In Vitro

Recently, selenium nanoparticles have been drawing attention worldwide, and it is crucial to increase the stability of nano-Se. Morinda officinalis polysaccharides (MOP) are the main active component in Morinda officinalis radix. However, their low activity has limited their application. A novel selenium nanoparticle (Se-MOP) was prepared to solve these problems using MOP as a dispersant. The zeta potential was measured to evaluate the stability, and UV and ATR-FTIR were used to investigate the binding type of selenium and MOP. The morphology was observed by the TEM method. Furthermore, the inhibitory effect on five selected cancer cells (HepG2, MCF-7, AGS, PC9, and HCT8) was evaluated, showing remarkable inhibition of all five cancer cells. The mechanism of inhibition was also investigated by cell circle assay, and it was found that Se-MOP could induce cell circle G0/G1 phase arrest. Immune-enhancing activities were evaluated by measuring the proliferation and cytokines of mouse spleen lymphocytes in vitro and quantitative RT-PCR. The results indicated that single stimulation of Se-MOP and synergistic stimulation with PHA or LPS increased immune capacity and improved immune by increasing the expression of cytokines.

Neuroprotective effects of Morinda officinalis How.: Anti-inflammatory and antioxidant roles in Alzheimer’s disease

Pharmacological studies have shown that some traditional Chinese medicines (TCMs) have applications in the treatment of Alzheimer’s disease (AD). Morinda officinalis How. (MO) is a TCM with a long history and is widely used to tonify kidney Yang. In vitro and in vivo experiments have suggested that MO contains various effective pharmaceutical components and chemicals, including oligosaccharides, anthraquinones, iridoids, flavonoids, amino acids, and trace elements, conferring MO with anti-inflammatory and antioxidant properties. Neuroinflammation and oxidative stress are undoubtedly hallmarks of neurodegeneration, contributing to AD progression. In this mini-review, we summarize the molecular mechanisms, structure-activity relationships, and potential synergistic and antagonistic effects of active components in MO. This discussion highlights the roles of these active components, such as oligosaccharides, anthraquinones, and iridoid glycosides, in the treatment of AD via anti-inflammatory and antioxidant mechanisms, providing a scientific basis for further utilization of MO.

Anti-Alzheimer's disease potential of traditional chinese medicinal herbs as inhibitors of BACE1 and AChE enzymes

Alzheimer's disease (AD) is a common neurodegenerative disease that often occurs in the elderly population. At present, most drugs for AD on the market are single-target drugs, which have achieved certain success in the treatment of AD. However, the efficacy and safety of single-target drugs have not achieved the expected results because AD is a multifactorial disease. Multi-targeted drugs act on multiple factors of the disease network to improve efficacy and reduce adverse reactions. Therefore, the search for effective dual-target or even multi-target drugs has become a new research trend. Many of results found that the dual-target inhibitors of the beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) and acetylcholinesterase (AChE) found from traditional Chinese medicine have a good inhibitory effect on AD with fewer side effects. This article reviews sixty-six compounds extracted from Chinese medicinal herbs, which have inhibitory activity on BACE1 and AChE. This provides a theoretical basis for the further development of these compounds as dual-target inhibitors for the treatment of AD.

Iridoids with anti-inflammatory effect from the aerial parts of Morinda officinalis How

Morinda officinalis How was widely applied to alleviate symptom like impotence, menstrual disorders, osteoporosis, and rheumatoid arthritis. To expand resources usage, phytochemistry of the aerial parts was studied and the structures of compounds were elucidated based on NMR, HRESIMS, IR and UV. Moreover, the anti-inflammatory effect and possible mechanism were investigated by Griess kit, RT-qPCR, ELISA, western blot and molecular docking on LPS-induced inflammation in RAW 264.7 cells. Herein, we isolated and identified 16 iridoid derivatives, including seven new iridoids officinaloside A-G (1-7) and nine known iridoids. All the compounds were safe to RAW 264.7 cells. Luckily, compounds 5 and 6 showed inhibitory effect on production of NO, and decreased the expression of inflammatory cytokines at mRNA and protein levels in a dose-dependent way. The possible mechanism of their anti-inflammation may be the affinity interaction between 5 with COX-2 protein, and 6 with iNOS protein. Overall, compounds 5 and 6 exert promising effects in inhibiting inflammatory cytokines, indicating that they could be used as lead compounds for developing health products or clinical practice for inflammation, which provides a scientific basis for further sustainable development and usage of the aerial parts of Morinda officinalis How.

Development of Simultaneous Analysis Method for Multi-Compounds Content of New Shilajit Using HPLC-UV and the Cognitive Enhancing Effect: Mongolian Shilajit

Shilajit has a longstanding use as an anti-aging and memory enhancing drug. It is known to have excellent anti-bacterial effects and is believed to be effective for cognitive enhancement, but is difficult to standardize because of the lack of quality control standards. This study, for the first time, proposes a quality control standard using a simultaneous analytical method for the drug’s multi-compound content using high-performance liquid chromatography-ultraviolet detection (HPLC-UV) as an aid for the internationalization of Mongolian Shilajit. Phenolic compounds 1-6 were isolated from Mongolian Shilajit extract using bioassay-guided isolation, and the isolated compounds were evaluated for cognitive-related anti-Alzheimer’s disease (AD) activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), and advanced glycation end-product (AGE) formation assays. The isolated compounds showed good effects for each activity. In addition, the isolated compounds were successfully quantified using a validated quantitative HPLC analysis method. As a result, the isolated compounds were suggested as standard marker compounds for Mongolian Shilajit. Also, we proved that the original material of Mongolian Shilajit is a lichen named Xanthoparmelia somloensis (Gyel.) Hale using HPLC-UV, ultra-high-performance liquid chromatography-electrospray ionization/hybrid linear trap-quadruple-orbitrap-high-resolution mass spectrometry (UHPLC-ESI/LTQ-HRMS).

Anti-inflammatory naphthoates and anthraquinones from the roots of Morinda officinalis

Morinda (Morinda officinalis) is widely consumed as a health-care herb in Asia and reported to possess various biological activities. In this study, anti-inflammatory phytochemicals were investigated and two pairs of new methyl-2-naphthoate enantiomers (1a/1b, 2a/2b), one new anthraquinone (3), three new natural unknown anthraquinones (5-6, 23), and eighteen known anthraquinones were isolated and elucidated from the roots of morinda. Anti-inflammatory activities of the isolated compounds were assessed in lipopolysaccharide-stimulated RAW 264.7 macrophages. Compounds 2b and 19 significantly inhibited the production of NO with IC₅₀ values of 34.32 ± 4.87 and 17.17 ± 4.13 μM (indomethacin, IC₅₀ 26.71 ± 6.32 μM), and they were further corroborated via immunoblotting, quantitative real-time PCR and immunofluorescence staining assays. They could dose-dependent suppress lipopolysaccharide-stimulated pro-inflammatory factors (COX-2 and iNOS) production and block nuclear translocation of NF-κB. The results implied that reasonable consumption of morinda may be beneficial for preventing and reducing the occurrence of inflammatory-associated diseases.

Journey on Naphthoquinone and Anthraquinone Derivatives: New Insights in Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative disease that is characterized by memory loss, cognitive impairment, and functional decline leading to dementia and death. AD imposes neuronal death by the intricate interplay of different neurochemical factors, which continue to inspire the medicinal chemist as molecular targets for the development of new agents for the treatment of AD with diverse mechanisms of action, but also depict a more complex AD scenario. Within the wide variety of reported molecules, this review summarizes and offers a global overview of recent advancements on naphthoquinone (NQ) and anthraquinone (AQ) derivatives whose more relevant chemical features and structure-activity relationship studies will be discussed with a view to providing the perspective for the design of viable drugs for the treatment of AD. In particular, cholinesterases (ChEs), β-amyloid (Aβ) and tau proteins have been identified as key targets of these classes of compounds, where the NQ or AQ scaffold may contribute to the biological effect against AD as main unit or significant substructure. The multitarget directed ligand (MTDL) strategy will be described, as a chance for these molecules to exhibit significant potential on the road to therapeutics for AD.

Two new naphthoate derivatives from Morinda officinalis

Two new naphthoate derivatives, including a symmetrical dimer (1) and a monomer (2), were separated from the roots of Morinda officinalis var. hirsuta. Their structures were characterized on the basis of spectroscopic means especially MS and NMR methods. Biological evaluations revealed that the two compounds did not show inhibition against both cholinesterases AChE and BChE, while the dimer (1) did exhibit moderate growth inhibitory activity toward one human osteosarcoma cell line U2OS with an IC₅₀ value of 18.5 ± 1.1 μM.

Effects of the Salt-Processing Method on the Pharmacokinetics and Tissue Distribution of Orally Administered Morinda officinalis How. Extract

Salt processing, which involves steaming with salt water, directs herbs into the kidney channel. After being salt processed, kidney invigorating effects occur. However, the underlying mechanism of this method remains elusive. The compounds monotropein, rubiadin, and rubiadin 1-methyl ether are the major effective components of Morinda officinalis How. To clarify the pharmacokinetics and tissue distribution of these three compounds, we employed liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to determine the contents of the three components in rat plasma and tissues. Separation was achieved on an Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 μm, Waters). Formic acid aqueous solution (0.1%; A) and acetonitrile (containing 0.1% formic acid; B) were used as the mobile phase system with a programmed elution of 0∼5 min with 70% A and then 5∼7 min with 60% A. All analytes were measured with optimized multiple reaction monitoring (MRM) in negative ion mode. Geniposide and 1,8-dihydroxyanthraquinone were used as the internal standards (IS). The linear ranges were 1.2∼190, 1.3∼510, and 0.047∼37.5 μg/mL, respectively. Compared with the Morinda officinalis without wood (MO) group, the C_max and AUC_0-t parameters of rubiadin and rubiadin 1-methyl ether elevated remarkably for the salt-processed Morinda officinalis (SMO) groups, which indicates that steaming by salt could increase the bioavailability of rubiadin and rubiadin 1-methyl ether. The T _max for monotropein is shorter (0.5 h) in SMO groups than that in MO group, which means that monotropein was quickly absorbed in the SMO extract. Moreover, the contents of three compounds in the small intestine were the highest.

Chemical Diversity of β-Secretase Inhibitors From Natural Resources

Reports on β-secretase inhibitors of natural origin are listed in order to reveal their chemical diversity. Various types of compounds were found to inhibit β-secretase, and natural resources included a wide spectrum of biological species. Among them, some triterpenes and moracin derivatives, which are nonpeptidic compounds, were determined to be competitive inhibitors. In addition, no peptide compounds were reported from natural resources. These points will be clarified in future studies.

Indian Morinda species: A review

Morinda is a largest genus of Rubiaceae family, and its 11 species are found in India. In India, plant species are known by several common names as great morinda, Indian mulberry, noni, beach mulberry and cheese fruit. Various Morinda products (capsules, tablets, skin products and fruit juices) are available in the market, used by people for treatment of several health complaints. A diversity of phytochemicals including iridoids, flavonoids, flavonoid glycosides, anthraquinones, coumarins, lignanas, noniosides, phenolics and triterpenoids have been reported from Morinda species. Morinda species are used in the treatment of inflammation, cancer, diabetes, psyquiatric disorders, and bacterial and viral infections. The noni fruit juice (Morinda citrifolia) and its products are used clinically in the treatment of cancer, hypertension and cervical spondylosis affecting patients. M. citrifolia fuit juice, with different doses, is used in the maintaining blood pressure and reducing of superoxides, HDL and LDL levels. Similarly, oligosaccharide capsules and tablets of root extract of M. officinalis are recommended as medicine for the treatment of kidney problems and sexual dysfunctions of patients. The toxicological studies revealed that higher doses of fruit juice (4,000 or 5,000 mg/kg) of M. citrifolia for 2 or more months cause toxic effects on liver and kidneys. M. officinalis root extracts (ethanolic and aqueous) are found fully safe during treatment of diseases. A large number of reviews are available on M. citrifolia but very few studies are conducted on other Indian Morinda species. This review reports the comprehensive knowledge on state-wise distribution, botany, ethnomedicinal uses, phytochemistry, pharmacological activities, clinical applications and toxicological evaluations of 11 species of Morinda found in India.

Regulation of P-glycoprotein by Bajijiasu in vitro and in vivo by activating the Nrf2-mediated signalling pathway

CONTEXT

Bajijiasu (BJJS), a main bioactive compound from Morinda officinalis F.C. How. (Rubiaceae), is widely administered concomitantly with other drugs for treating male impotence, female infertility, fatigue, chronic rheumatism, depression, etc. Objective: This study investigates the regulation of P-glycoprotein (P-gp) by BJJS in vitro and in vivo.

MATERIAL AND METHODS

HepG2 cells were incubated with BJJS (10, 20 or 40 μM) for 48 h. C57 mice were orally treated with BJJS (25, 50 or 100 mg/kg) for 2 weeks. The protein and mRNA levels of P-gp were measured by using Western blot and real-time PCR, respectively. siNrf2 RNA was used to explore the mediation effects of Nrf2 on the P-gp expression. The efflux activity of P-gp was tested via a flow cytometry.

RESULTS

Incubation of HepG2 cells with BJJS at 10, 20, and 40 μM up-regulated the P-gp protein expression by 12.3%, 82.9%, and 134.3%, respectively. Treatment of C57 mice with BJJS at 25, 50 and 100 mg/kg increased the P-gp protein expression by 49.3%, 75.8% and 106.0%, respectively. Incubation of the cells with BJJS at 10, 20 and 40 μM up-regulated the total Nrf2 protein levels by 34.3%, 93.1% and 118.6%, respectively, and also increased the nuclear Nrf2 protein levels by 14.8%, 44.4% and 59.25%, respectively. The total Nrf2 protein levels were increased by 46.3%, 66.5%, and 87.4%, respectively, in the mice exposed to BJJS at 25, 50, and 100 mg/kg. Inhibition of Nrf2 by siRNA diminished the P-gp induction by 25.0%, 33.4%, and 38.7%, respectively, in the cells. In addition, BJJS enhanced the efflux activity of P-gp by 9.6%, 37.1%, and 48.1%, respectively, in the cells.

CONCLUSIONS

BJJS activates Nrf2 to induce P-gp expression, and enhanced the efflux activity of P-gp. The possibility of potential herb-drug interactions when BJJS is co-administered with other P-gp substrate drugs should be carefully monitored.

Bazhu Decoction, a Traditional Chinese Medical Formula, Ameliorates Cognitive Deficits in the 5xFAD Mouse Model of Alzheimer's Disease

Alzheimer’s disease (AD) is the most common neurodegenerative disorder associated with aging. There are currently no effective treatments for AD. Bazhu decoction (BZD), a traditional Chinese medicine (TCM) formula, has been employed clinically to alleviate AD. However, the underlying molecular mechanisms are still unclear. Here we found that middle- and high-doses of BZD ameliorated the behavioral aspects of 5xFAD transgenic mice in elevated plus maze, Y maze and Morris water maze tests. Moreover, BZD reduced the protein levels of BACE1 and PS1, resulting in a reduction of Aβ plaques. We also identified a beneficial effect of BZD on oxidative stress by attenuating MDA levels and SOD activity in the brains of 5xFAD mice. Together, these results indicate that BZD produces a dose-dependent positive effect on 5xFAD transgenic mouse model by decreasing APP processing and Aβ plaques, and by ameliorating oxidative damage. BZD may play a protective role in the cognitive and anxiety impairments and may be a complementary therapeutic option for AD.

Hypoglycemic, Antiglycation, and Cytoprotective Properties of a Phenol-Rich Extract From Waste Peel of Punica granatum L. var. Dente di Cavallo DC2

Pomegranate peel is a natural source of phenolics, claimed to possess healing properties, among which are antioxidant and antidiabetic. In the present study, an ethyl acetate extract, obtained by Soxhlet from the peel of Dente di Cavallo DC2 pomegranate (PGE) and characterized to contain 4% w/w of ellagic acid, has been evaluated for its hypoglycemic, antiglycation, and antioxidative cytoprotective properties, in order to provide possible evidence for future nutraceutical applications. The α-amylase and α-glucosidase enzyme inhibition, interference with advanced glycation end-products (AGE) formation, and metal chelating abilities were studied. Moreover, the possible antioxidant cytoprotective properties of PGE under hyperglycemic conditions were assayed. Phenolic profile of the extract was characterized by integrated chromatographic and spectrophotometric methods. PGE resulted able to strongly inhibit the tested enzymes, especially α-glucosidase, and exerted chelating and antiglycation properties. Also, it counteracted the intracellular oxidative stress under hyperglycemic conditions, by reducing the levels of reactive oxygen species and total glutathione. Among the identified phenolics, rutin was the most abundant flavonoid (about 4 % w/w). Present results suggest PGE to be a possible remedy for hyperglycemia management and encourage further studies to exploit its promising properties.

Strategies to target bioactive molecules to subcellular compartments. Focus on natural compounds

Many potential pharmacological targets are present in multiple subcellular compartments and have different pathophysiological roles depending on location. In these cases, selective targeting of a drug to the relevant subcellular domain(s) may help to sharpen its impact by providing topological specificity, thus limiting side effects, and to concentrate the compound where needed, thus increasing its effectiveness. We review here the state of the art in precision subcellular delivery. The major approaches confer "homing" properties to the active principle via permanent or reversible (in pro-drug fashion) modifications, or through the use of special-design nanoparticles or liposomes to ferry a drug(s) cargo to its desired destination. An assortment of peptides, substituents with delocalized positive charges, custom-blended lipid mixtures, pH- or enzyme-sensitive groups provide the main tools of the trade. Mitochondria, lysosomes and the cell membrane may be mentioned as the fronts on which the most significant advances have been made. Most of the examples presented here have to do with targeting natural compounds - in particular polyphenols, known as pleiotropic agents - to one or the other subcellular compartment.

Morinda Officinalis Polysaccharides Attenuate Varicocele-Induced Spermatogenic Impairment through the Modulation of Angiogenesis and Relative Factors

Evidence supporting best treatment practices for varicocele is lacking. The effects of a water-soluble polysaccharide extracted from Morinda officinalis (MOP) on the progression of varicocele were evaluated in the present study. The extracted MOP was confirmed as having a high purity of 98% with scant protein contamination, and it mainly consisted of glucose, lactose, and xylose at a molar ratio of 7.63:1.23:0.95 glucose:lactose:xylose. MOPs were administered to experimental left varicocele rats immediately after surgery at doses ranging from 25 to 200 mg/kg. As detected by sperm analysis and histopathological staining, the intragastric administration of 100 mg/kg MOPs significantly improved the sperm parameters of bilateral cauda epididymis, attenuated seminiferous epithelial structures, and inhibited germ cell apoptosis. The results of immunofluorescence and immunoblot showed that administration of 100 mg/kg MOPs effectively inhibited angiogenesis in the bilateral testes but modulated the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase 2 (MMP2), and MMP9 mildly. These results indicate that inhibition of angiogenesis may be one of the mechanisms by which MOP exerts its inhibitive activities on the progression of varicocele, whereas a relative upregulation of VEGF and MMP-9 may be crucial for the spermatogenetic protective effects of 100 mg/kg MOP administration.

Drug Discovery on Natural Products: From Ion Channels to nAChRs, from Nature to Libraries, from Analytics to Assays

Natural extracts are complex mixtures that may be rich in useful bioactive compounds and therefore are attractive sources for new leads in drug discovery. This review describes drug discovery from natural products and in explaining this process puts the focus on ion-channel drug discovery. In particular, the identification of bioactives from natural products targeting nicotinic acetylcholine receptors (nAChRs) and serotonin type 3 receptors (5-HT3Rs) is discussed. The review is divided into three parts: "Targets," "Sources," and "Approaches." The "Targets" part will discuss the importance of ion-channel drug targets in general, and the α7-nAChR and 5-HT3Rs in particular. The "Sources" part will discuss the relevance for drug discovery of finding bioactive compounds from various natural sources such as venoms and plant extracts. The "Approaches" part will give an overview of classical and new analytical approaches that are used for the identification of new bioactive compounds with the focus on targeting ion channels. In addition, a selected overview is given of traditional venom-based drug discovery approaches and of diverse hyphenated analytical systems used for screening complex bioactive mixtures including venoms.

Pharmacokinetics and tissue distribution of monotropein and deacetyl asperulosidic acid after oral administration of extracts from Morinda officinalis root in rats

BACKGROUND

Iridoid glycosides (IGs), including monotropein (MON) and deacetyl asperulosidic acid (DA) as the main ingredients, are the major chemical components in Morinda officinalis How. (MO) root, possessing various pharmacological properties including anti-osteoporosis, anti-inflammation and anti-rheumatism activities.The aim of the present study was to further elucidate the pharmacological actions of MO by investigating the pharmacokinetics and tissue distribution of IGs in MO.

METHODS

An ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS) method was developed and validated for simultaneous determination of MON and DA levels in plasma and various tissues of Wistar rats. MON, DA and acetaminophen (ACE) as the internal standard (IS) were extracted from rat plasma and tissue samples by direct deproteinization with methanol. The rats were administered orally at 1650 mg/kg MO and 25, 50 and 100 mg/kg MO iridoid glycosides (MOIGs) or intravenously at MOIG 25 mg/kg for pharmacokinetic study of MON and DA. In addition, 100 mg/kg MOIG was administered orally for tissue distribution study of MON and DA. Non-compartmental pharmacokinetic profiles were constructed. Tissue distributions were calculated according to the validated methods.

RESULTS

Significant differences in the pharmacokinetic parameters were observed in male and female rats. The AUC0-t, Cmax and bioavailability of MON and DA in female rats were higher than those in male rats. MON and DA mainly distributed in the intestine and stomach after oral administration, and noteworthily high concentrations of MON and DA were detected in the rat hypothalamus.

CONCLUSION

The results of the present study may shed new lights on the biological behavior of MOIGs in vivo, help explain their pharmacological actions, and provide experimental clues for rational clinical use of these IGs extracted from the MO root.

Inhibitory Effects of Bioassay-Guided Isolation of Anti-Glycation Components from Taraxacum coreanum and Simultaneous Quantification

Inhibition of the formation of advanced glycation end products (AGEs) is an attractive strategy in diabetes treatment. Taraxacum coreanum extracts were suggested to have antidiabetic effects. However, studies on the components of T. coreanum are lacking, and there is no report on the inhibitory effects of T. coreanum on the formation of AGEs. Therefore, T. coreanum extracts and fractions were tested for their inhibitory effects on α-glucosidase and AGEs formation in two systems (bovine serum albumin (BSA)⁻glucose and BSA⁻methylglyoxal (MGO)). Bioassay-guided isolation of compounds from T. coreanum led to six flavones (1⁻6) and four hydroxycinnamic acid derivatives (7⁻11). Compound 11 exhibited the highest inhibitory activity against α-glucosidase and AGEs formation and had the highest content in T. coreanum extract. All compounds except compound 9 showed a stronger inhibition than the positive control in the BSA-glucose and BSA-MGO system. In addition, T. coreanum showed a higher content of bioactive compounds and stronger inhibition of AGE formation and α-glucosidase activity than T. officinale. Our study demonstrated the preventive and therapeutic efficacy of T. coreanum and its potential use as a cost-effective phytopharmaceutical in complementary therapy against type-2 diabetes and its complications.