Phenylethanoid Glycosides of Cistanche Improve Learning and Memory Disorders in APP/PS1 Mice by Regulating Glial Cell Activation and Inhibiting TLR4/NF-κB Signaling Pathway

Phenylethanoid Glycosides of Cistanche (PhGs) have a certain curative effect on AD animal model, Echinacea (ECH) and verbascoside (ACT), as the quality control standard of Cistanche deserticola Y. C. Ma and the main representative compounds of PhGs have been proved to have neuroprotective effects, but the specific mechanism needs to be further explored. This study explored the mechanisms of PhGs, ECH, and ACT in the treatment of Alzheimer's disease (AD) from the perspectives of glial cell activation, TLR4/NF-κB signaling pathway, and synaptic protein expression. We used APP/PS1 mice as AD models. After treatment with PhGs, ECH, and ACT, the learning and memory abilities of APP/PS1 mice were enhanced, and the pathological changes in brain tissue were alleviated. The expression of pro-inflammatory M1 microglia markers (CD11b, iNOS, and IL-1β) was decreased; the expression of M2 microglia markers (Arg-1 and TGF-β1) was increased, which promoted the transformation of microglia from M1 pro-inflammatory phenotype to M2 anti-inflammatory phenotype. In addition, PhGs, ECH, and ACT could down-regulate the expression of proteins related to the TLR4/NF-κB signaling pathway and up-regulate the expression of synaptic proteins. The results indicated that PhGs, ECH, and ACT played a neuroprotective role by regulating the activation of glial cells and inhibiting the TLR4/NF-κB inflammatory pathway, and improving the expression levels of synapse-related proteins.

Combining LC-MS/MS profiles with network pharmacology to predict molecular mechanisms of the hyperlipidemic activity of Lagenaria siceraria stand

ETHNOPHARMACOLOGICAL RELEVANCE

Lagenaria siceraria Stand. (Family: Cucurbitaceae), popularly known as bottle gourd, is traditionally used in Ayurvedic medicine as a food plant, especially in hypertension and obesity.

AIM OF THE STUDY

Investigations were undertaken to assign novel lead combinations from this common food plant to multi-molecular modes of actions in the complex disease networks of obesity and hypertension. LC-MS/MS based metabolite screening, in-vivo high fat diet induced hyperlipidemia animal study and network pharmacology explorations of the mechanism of action for lipid lowering effects including a neighbourhood community approach for molecular combinations were performed.

MATERIAL AND METHODS

Major chemical constituents of the fruits of LS (LSFE) were analysed by HPLC-DAD-MS/MS-QTOF. Wistar albino rats (n = 36), divided into 6 groups (n = 6) received either no treatment or a high-fat diet along with LSFE or Atorvastatin. Lipid profiles and biochemical parameters were evaluated. In silico cross-validated network analyses using different databases and Cytospace were applied.

RESULTS

Profiling of LSFE revealed 18 major constituents: phenolic acids like p-Coumaric acid and Ferulic acid, the monolignolconferyl alcohol, the flavonoid glycosides hesperidin and apigenin-7-glucoside. Hyperlipidemic animals treated with LSFE (200 mg/kg, 400 mg/kg, 600 mg/kg) showed a significant improvement of their lipid profiles after 30 days of treatment. Network pharmacology analyses for the major 18 compounds revealed enrichment of the insulin and the ErbB signalling pathway. Novel target node combinations (e.g. AKR1C1, AGXT) including their connection to different pathways were identified in silico.

CONCLUSIONS

The combined in vivo and bioinformatics analyses propose that lead compounds of LSFE act in combination on relevant targets of hyperlipidemia. Perturbations of the IRS→Akt→Foxo1 cascade are predicted which suggest further clinical investigation towards development of safe natural alternative to manage hyperlipidemia.

Integration of pharmacodynamics and metabolomics reveals the therapeutic effects of 6-acetylacteoside on ovariectomy-induced osteoporosis mice

BACKGROUND

6-acetylacteoside (6-AA) is a phenylethanoid glycoside isolated from Cistanche deserticola which had been previously proven to possess anti-osteoporotic activity previously. Currently, it is still unknown whether 6-AA plays a crucial role on the anti-osteoporotic effects of C. deserticola.

PURPOSE

To elucidate the therapeutic effect and mechanism of 6-AA on osteoporosis by employing an ovariectomized mouse model in vivo and RAW264.7 cells in vitro.

METHODS

Sixty female ICR mice were randomly assigned into six groups: sham-operated control group (SHAM, vehicle), ovariectomized model group (OVX, vehicle), positive group (EV, 1 mg/kg/day of estradiol valerate), low dosage (10 mg/kg/day of 6-AA), medium dosage (20 mg/kg/day of 6-AA) and high dosage (40 mg/kg/day of 6-AA) treatment groups. All substances were administered daily by intragastric gavage. After 12 weeks of intervention, trabecular bone microarchitecture was estimated and bone biomechanics were determined. Bone formation and resorption factors were determined by using the corresponding Elisa kits. The related proteins and metabolites were estimated by using western-blot and metabolomics techniques.

RESULTS

OVX mice demonstrated significant atrophy of the uterine and vagina, declined biomechanical parameters such as flexural strength and maximum load, deteriorated trabecular bone microarchitecture such as decreased BMD, BMC, TMC, TMD, BVF, Tb. N, and Tb. Th and increased Tb. Sp, as well as increased bone resorption factors such as TRAP, cathepsin K, and DPD, all after 12 weeks of ovariectomy operation. Following administration of 6-AA to OVX mice, parameters related to the bone microarchitecture, bone resorption activities as well as biomechanical properties were all significantly improved. Meanwhile, the levels of NF-κB, NFATc1, RANK, RANKL and TRAF6 were significantly downregulated, while OPG, PI3K and AKT were upregulated after 6-AA intervention. This indicates that, 6-AA could prevent bone resorption by regulating the RANKL/RANK/OPG mediated NF-κB and PI3K/AKT pathways. Furthermore, 26 different metabolites corresponding to 25 metabolic pathways were identified, and 5 of which were related to the formation of osteoporosis. Interestingly, 23 abnormal metabolites were recovered after 6-AA treatment.

CONCLUSION

Our results revealed the significant anti-osteoporotic effects of 6-AA on ovariectomized mice which were probably exerted via suppression of osteoclast formation and bone resorption.

Structure-Guided Approach to Discover Tuberosin as a Potent Activator of Pyruvate Kinase M2, Targeting Cancer Therapy

Metabolic reprogramming is a key attribute of cancer progression. An altered expression of pyruvate kinase M2 (PKM2), a phosphotyrosine-binding protein is observed in many human cancers. PKM2 plays a vital role in metabolic reprogramming, transcription and cell cycle progression and thus is deliberated as an attractive target in anticancer drug development. The expression of PKM2 is essential for aerobic glycolysis and cell proliferation, especially in cancer cells, facilitating selective targeting of PKM2 in cell metabolism for cancer therapeutics. We have screened a virtual library of phytochemicals from the IMPPAT (Indian Medicinal Plants, Phytochemistry and Therapeutics) database of Indian medicinal plants to identify potential activators of PKM2. The initial screening was carried out for the physicochemical properties of the compounds, and then structure-based molecular docking was performed to select compounds based on their binding affinity towards PKM2. Subsequently, the ADMET (absorption, distribution, metabolism, excretion and toxicity) properties, PAINS (Pan-assay interference compounds) patterns, and PASS evaluation were carried out to find more potent hits against PKM2. Here, Tuberosin was identified from the screening process bearing appreciable binding affinity toward the PKM2-binding pocket and showed a worthy set of drug-like properties. Finally, molecular dynamics simulation for 100 ns was performed, which showed decent stability of the protein-ligand complex and relatival conformational dynamics throughout the trajectory. The study suggests that modulating PKM2 with natural compounds is an attractive approach in treating human malignancy after required validation.

Effectiveness and safety of tripterygium glycosides tablet for lupus nephritis: a systematic review and Meta-analysis

OBJECTIVE

To investigate the effectiveness and safety of tripterygium glycosides (TG) tablet for the treatment of Lupus nephritis (LN).

METHODS

Several databases were systematically searched including PubMed, Embase, Cochrane, Wiley, China National Knowledge Infrastructure Database, SinoMed and Wanfang Library till June 20, 2020. Revman5.3 was utilized to analyze the data according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement.

RESULTS

In total, 8 randomized controlled trials involving 583 participants were identified. Meta-analyses showed that, compared with glucocorticoids (GC) alone, the combination with TG tablet provided a statistically significant improvement in total remission (TR) ( = 1.27, 95% : 1.08-1.50, = 0.004), complete remission (CR) ( = 1.61, 95% : 1.05-2.47, = 0.03) and C3 levels ( = 0.27, 95% : 0.14-0.39, < 0.000 1), C4 levels ( = 0.12, 95% : 0.07-0.17, < 0.000 01). No significant differences were seen in TR, CR, proteinuria, serum creatinine, C3 and C4 (TR: = 1.00, 95% : 0.87-1.16, = 0.95; CR: = 1.10, 95% : 0.78-1.56, = 0.58; proteinuria levels: = -0.06, 95% : -0.13 to 0.01, = 0.10; serum creatinine levels: = -0.01, 95%: -7.36 to 7.35, = 1.00; C3 levels: = 0.01, 95%: -0.06 to 0.07, = 0.84; C4 levels: = -0.01, 95%: -0.03 to 0.01, = 0.49) between azathioprine (AZA) / leflomit (LEF) + GC and TG tablet + GC. Adverse events (hepatic dysfunction, nausea, vomitting) showed no statistical differences between the TG tablet + GC group and the GC group. There were more new onset of irregular menstruation in the TG tablet + GC group than those in the AZA + GC ( = 3.57, 95% : 1.40-9.11, = 0.008) /LEF+ GC ( = 6.69, 95% : 2.42-18.46, = 0.000 2) group, but leucopenia lower than those in AZA + GC group ( = 0.38, 95% : 0.17-0.85, = 0.02) and alopecia ( = 0.14, 95% : 0.03-0.77, = 0.02) and rash ( = 0.09, 95% : 0.01-0.69, = 0.02) lower than those in LEF + GC group.

CONCLUSIONS

This review indicates that TG tablet maybe effective in LN treatment. Nevertheless, adverse events cannot be ignored. Large sample, multi-center, high-quality clinical studies are needed to verify the exact effects and safety of TG tablet in treatment of LN.

[Efficacy and mechanism of low glycoside from Epimedii Folium flavonoids on retinoic acid-induced osteoporosis in rats]

In this study, the secondary osteoporosis model was induced by oral administration of retinoic acid for two weeks in SD male rats. The efficacy and mechanism of LG on secondary osteoporosis in rats were explored through the bone morphogenetic protein 2(BMP-2)/Runt-related transcription factor 2(Runx2)/Osterix signaling pathway. With Xianling Gubao Capsules(XLGB) as the positive control, three dose groups of low glycoside from Epimedii Folium flavonoids(LG), i.e., low-dose group(LG-L), medium-dose group(LG-M), and high-dose group(LG-H), were set up. After modeling, the rats in each group were treated correspondingly by gavage for eight weeks. The action target of LG in the treatment of secondary osteoporosis in rats was analyzed by measuring the body weight and the organ indexes of rats including heart index and testis index. The efficacy of LG was characterized by the pathological changes of the femur, the microstructural parameters of the trabecular bone, and the biomechanical properties of femoral tissues in rats. The mechanism of LG was explored by measuring the relevant biochemical indexes and the changes in BMP-2, Runx2, and Osterix content in rats with secondary osteoporosis. The results showed that the action target of LG in the treatment of secondary osteoporosis in rats was the testis. LG can improve the bone loss of the femur, increase the number and thickness of the trabecular bone, reduce the porosity and separation of the trabecular bone, potentiate the resistance of bone to deformation and destruction, up-regulate the serum content of Ca, P, aminoterminal propeptide of type Ⅰ procollagen(PINP), and osteocalcin(OC), promote bone matrix calcification and the expression of BMP-2, Runx2, and Osterix proteins, and accelerate bone formation, thereby reducing the risk of fractures, and ultimately exerting anti-secondary osteoporosis efficacy.

Echinacoside Improves Cognitive Impairment by Inhibiting Aβ Deposition Through the PI3K/AKT/Nrf2/PPARγ Signaling Pathways in APP/PS1 Mice

Echinacoside (ECH), a phenylethanoid glycoside, has protective activity in neurodegenerative disease, including anti-inflammation and antioxidation. However, the effects of ECH in Alzheimer's disease (AD) are not very clear. This present study investigates the role and mechanism of ECH in the pathological process of AD. APP/PS1 mice treated with ECH in 50 mg/kg/day for 3 months. Morris water maze, nesting test, and immunofluorescence staining used to observe whether ECH could improve AD pathology. Western blot used to study the mechanism of ECH improving AD pathology. The results showed that ECH alleviated the memory impairment of APP/PS1 mice by reducing the time of escape latency as well as increasing the times of crossing the platform and rescued the impaired ability to construct nests. In addition, ECH significantly reduced the deposition of senile plaques in the brain and decreased the expression of BACE1 in APP/PS1 mice through activating PI3K/AKT/Nrf2/PPARγ pathway. Furthermore, ECH decreased ROS formation, GP91 and 8-OHdG expression, upregulated the expression of SOD1 and SOD2 as well as activating the PI3K/AKT/Nrf2 signaling pathway. Moreover, ECH inhibited glia cells activation, pro-inflammatory cytokine IL-1β and TNF-α release, NLRP3 inflammasome formation through TXNIP/Trx-1 signaling pathway. In conclusion, this paper reported that ECH improved cognitive function, inhibited oxidative stress, and inflammatory response in AD. Therefore, we suggest that ECH may considered as a potential drug for AD treatment.

The antitumour activity of C21 steroidal glycosides and their derivatives of Baishouwu: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Baishouwu has been used in China for thousands of years since it was first discovered in the late Tang Dynasty and flourished in the Song and Ming Dynasties. The Chinese herbal medicines named Baishouwu include Cynanchum auriculatum Royle ex Wight., Cynanchum bungei Decne. and Cynanchum wilfordii Hemsl. It is described in the Sign of Materia Medica as "sweet, bitter, reinforce liver and kidney, and non-toxic". It is widely used for nourishing the blood to expel wind, reinforcing liver and kidney, strengthening bones and muscles.

AIM OF THE REVIEW

In this review, the current research status of the C₂₁ steroidal glycosides and their derivatives of Baishouwu for malignant tumours and their anti-tumour mechanisms are discussed. This may lay the ground for potential application of Baishouwu and its active ingredients in the treatment of tumours.

MATERIALS AND METHODS

Scientific databases, including PubMed, Elsevier, Science Direct, Google Scholar, CNKI, WANFANG DATA and VIP were searched to gather data about Baishouwu and its C₂₁ steroidal glycosides and their derivatives.

RESULTS

Prior literature indicates that Baishouwu has important biological activities such as anti-tumour, anti-epileptic, reducing cholesterol, protection of liver and kidney and immunomodulatory, which are of increasing interest, especially its anti-tumour activity. Recent studies demonstrate that the C₂₁ steroidal glycosides of Baishouwu, which have prominent antitumour efficacy, are one of its main active ingredients. Presently, a variety of C₂₁ steroidal glycosides have been isolated from Baishouwu medicinal part, the tuberous root. This review summarizes the various antitumour activities of the C₂₁ steroidal glycosides and their derivatives of Baishouwu.

CONCLUSIONS

In this review, the antitumour effects and mechanisms of total C₂₁ steroidal glycosides and monomers and derivatives of Baishouwu in vitro and in vivo were summarized. Baishouwu can inhibit tumourigenesis by blocking tumour cell cycle progression, regulating numerous signaling pathways, promoting apoptosis, inhibiting tumour cells proliferation and metastasis, improving immunity and so on. This review provides a theoretical basis for inheriting and developing the medical heritage of the motherland, exploring the resources of traditional Chinese medicine for ethnic minorities and clinical rational drug use.

Targets of Tripterygium glycosides in systemic lupus erythematosus treatment: A network-pharmacology study

OBJECTIVE

We aimed to explore the underlying mechanism of Tripterygium glycosides (TGs) in treating systemic lupus erythematosus (SLE) through network-pharmacology approach.

METHODS

The protein targets of TGs' three active ingredients (triptolide, tripterine, and wilforlide) and SLE were identified by database search. Then, the intersection of the two groups was studied. The drug-target network between the active ingredients of TGs and the overlapping genes was constructed, visualized, and analyzed with Cytoscape software. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment were performed to analyze these genes. Finally, we validated our predictions of the potential targets through docking study.

RESULTS

A total of 55 overlapping genes were discovered. Results suggested that the TGs' mechanism in SLE treatment was associated with heat shock protein family A member 5, heat shock protein family A member 8, eukaryotic translation elongation factor 1 alpha 1, and so forth with their related 4042 gene network, which regulated ribosome, spliceosome, viral carcinogenesis, Epstein-Barr virus infection signaling, and so forth. Molecular-docking analysis proved that hydrogen bonding was the main form of interaction.

CONCLUSIONS

Our research provided the protein targets affected by TGs in SLE treatment. The key targets (CASP3, MAPK1, HIF1A, and so forth) involving 4042 proteins became the multitarget mechanism of TGs in SLE treatment.

Oral treatment for mucopolysaccharidosis VI: Outcomes of the first phase IIa study with odiparcil

Mucopolysaccharidosis (MPS) disorders are a group of rare, progressive lysosomal storage diseases characterized by the accumulation of glycosaminoglycans (GAGs) and classified according to the deficient enzyme. Enzyme replacement therapy (ERT) of MPS VI has limited effects on ophthalmic, cardiovascular, and skeletal systems. Odiparcil is an orally available small molecule that results in the synthesis of odiparcil-linked GAGs facilitating their excretion and reducing cellular and tissue GAG accumulation. Improve MPS treatment was a Phase 2a study of the safety, pharmacokinetics/pharmacodynamics, and efficacy of two doses of odiparcil in patients with MPS VI. The core study was a 26-week, randomized, double-blind, placebo-controlled trial in patients receiving ERT and an open-label, noncomparative, single-dose cohort not receiving ERT. Patients aged ≥ 16 years receiving ERT were randomized to odiparcil 250 or 500 mg twice daily or placebo. Patients without ERT received odiparcil 500 mg twice daily. Of 20 patients enrolled, 13 (65.0%) completed the study. Odiparcil increased total urine GAGs (uGAGs), chondroitin sulfate, and dermatan sulfate concentrations. A linear increase in uGAG levels and odiparcil exposure occurred with increased odiparcil dose. Odiparcil demonstrated a good safety and tolerability profile. Individual analyses found more improvements in pain, corneal clouding, cardiac, vascular, and respiratory functions in the odiparcil groups vs placebo. This study confirmed the mechanism of action and established the safety of odiparcil with clinical beneficial effects after only a short treatment duration in an advanced stage of disease. Further assessment of odiparcil in younger patients is needed.

MPS VI associated ocular phenotypes in an MPS VI murine model and the therapeutic effects of odiparcil treatment

Maroteaux - Lamy syndrome (mucopolysaccharidosis type VI, MPS VI) is a lysosomal storage disease resulting from insufficient enzymatic activity for degradation of the specific glycosaminoglycans (GAG) chondroitin sulphate (CS) and dermatan sulphate (DS). Among the most pronounced MPS VI clinical manifestations caused by cellular accumulation of excess CS and DS are eye disorders, in particular those that affect the cornea. Ocular manifestations are not treated by the current standard of care, enzyme replacement therapy (ERT), leaving patients with a significant unmet need. Using in vitro and in vivo models, we previously demonstrated the potential of the β-D-xyloside, odiparcil, as an oral GAG clearance therapy for MPS VI. Here, we characterized the eye phenotypes in MPS VI arylsulfatase B deficient mice (Arsb^-) and studied the effects of odiparcil treatment in early and established disease models. Severe levels of opacification and GAG accumulation were detected in the eyes of MPS VI Arsb^- mice. Histological examination of MPS VI Arsb^- eyes showed an aggregate of corneal phenotypes, including reduction in the corneal epithelium thickness and number of epithelial cell layers, and morphological malformations in the stroma. In addition, colloidal iron staining showed specifically GAG accumulation in the cornea. Orally administered odiparcil markedly reduced GAG accumulation in the eyes of MPS VI Arsb^- mice in both disease models and restored the corneal morphology (epithelial layers and stromal structure). In the early disease model of MPS VI, odiparcil partially reduced corneal opacity area, but did not affect opacity area in the established model. Analysis of GAG types accumulating in the MPS VI Arsb^- eyes demonstrated major contribution of DS and CS, with some increase in heparan sulphate (HS) as well and all were reduced with odiparcil treatment. Taken together, we further reveal the potential of odiparcil to be an effective therapy for eye phenotypes associated with MPS VI disease.

Ameliorating effect of continuous alpha-glycosyl isoquercitrin treatment starting from late gestation in a rat autism model induced by postnatal injection of lipopolysaccharides

The present study investigated the role of neuroinflammation and brain oxidative stress induced by neonatal treatment with lipopolysaccharides (LPS) on the development of autism spectrum disorder (ASD)-like behaviors and disruptive hippocampal neurogenesis in rats by exploring the chemopreventive effects of alpha-glycosyl isoquercitrin (AGIQ) as an antioxidant. AGIQ was dietary administered to dams at 0.25% or 0.5% (w/w) from gestational day 18 until postnatal day (PND) 21 on weaning and then to pups until the adult stage on PND 77. The pups were intraperitoneally injected with LPS (1 mg/kg body weight) on PND 3. At PND 6, LPS alone increased Iba1+ and CD68+ cell numbers without changing the CD163+ cell number and strongly upregulated pro-inflammatory cytokine gene expression (Il1a, Il1b, Il6, Nfkb1, and Tnf) in the hippocampus, and increased brain malondialdehyde levels. At PND 10, pups decreased ultrasonic vocalization (USV), suggesting the induction of pro-inflammatory responses and oxidative stress to trigger communicative deficits. By contrast, LPS alone upregulated Nfe2l2 expression at PND 6, increased Iba1+, CD68+, and CD163+ cell numbers, and upregulated Tgfb1 at PND 21, suggesting anti-inflammatory responses until the weaning period. However, LPS alone disrupted hippocampal neurogenesis at weaning and suppressed social interaction parameters and rate of freezing time at fear acquisition and extinction during the adolescent stage. On PND 77, neuroinflammatory responses had mostly disappeared; however, disruptive neurogenesis and fear memory deficits were sustained. AGIQ ameliorated most changes on acute pro-inflammatory responses and oxidative stress at PND 6, and the effects on USVs at PND 10 and neurogenesis and behavioral parameters throughout the adult stage. These results suggested that neonatal LPS treatment induced acute but transient neuroinflammation, triggering the progressive disruption of hippocampal neurogenesis leading to abnormal behaviors in later life. AGIQ treatment was effective for ameliorating LPS-induced progressive changes by critically suppressing initial pro-inflammatory responses and oxidative stress.

Identification of Flavonoid C-Glycosides as Promising Antidiabetics Targeting Protein Tyrosine Phosphatase 1B

Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of the insulin signaling pathway, has gained attention as a validated druggable target in the management of type 2 diabetes mellitus (T2DM). The lack of clinically approved PTP1B inhibitors has continued to prompt research in plant-derived therapeutics possibly due to their relatively lesser toxicity profiles. Flavonoid C-glycosides are one of the plant-derived metabolites gaining increased relevance as antidiabetic agents, but their possible mechanism of action remains largely unknown. This study investigates the antidiabetic potential of flavonoid C-glycosides against PTP1B in silico and in vitro. Of the seven flavonoid C-glycosides docked against the enzyme, three compounds (apigenin, vitexin, and orientin) had the best affinity for the enzyme with a binding score of -7.3 kcal/mol each, relative to -7.4 kcal/mol for the reference standard, ursolic acid. A further probe (in terms of stability, flexibility, and compactness) of the complexes over a molecular dynamics time study of 100 ns for the three compounds suggested orientin as the most outstanding inhibitor of PTP1B owing to its overall -34.47 kcal/mol binding energy score compared to ursolic acid (-19.24 kcal/mol). This observation was in accordance with the in vitro evaluation result, where orientin had a half maximal inhibitory concentration (IC₅₀) of 0.18 mg/ml relative to 0.13 mg/ml for the reference standard. The kinetics of inhibition of PTP1B by orientin was mixed-type with V _max and K _m values of 0.004 μM/s and 0.515 μM. Put together, the results suggest orientin as a potential PTP1B inhibitor and could therefore be further explored in the management T2DM as a promising therapeutic agent.

Glycosides for Peripheral Neuropathic Pain: A Potential Medicinal Components

Neuropathic pain is a refractory disease that occurs across the world and pharmacotherapy has limited efficacy and/or safety. This disease imposes a significant burden on both the somatic and mental health of patients; indeed, some patients have referred to neuropathic pain as being ‘worse than death’. The pharmacological agents that are used to treat neuropathic pain at present can produce mild effects in certain patients, and induce many adverse reactions, such as sedation, dizziness, vomiting, and peripheral oedema. Therefore, there is an urgent need to discover novel drugs that are safer and more effective. Natural compounds from medical plants have become potential sources of analgesics, and evidence has shown that glycosides alleviated neuropathic pain via regulating oxidative stress, transcriptional regulation, ion channels, membrane receptors and so on. In this review, we summarize the epidemiology of neuropathic pain and the existing therapeutic drugs used for disease prevention and treatment. We also demonstrate how glycosides exhibit an antinociceptive effect on neuropathic pain in laboratory research and describe the antinociceptive mechanisms involved to facilitate the discovery of new drugs to improve the quality of life of patients experiencing neuropathic pain.

Naturally Occurring Chromone Glycosides: Sources, Bioactivities, and Spectroscopic Features

Chromone glycosides comprise an important group of secondary metabolites. They are widely distributed in plants and, to a lesser extent, in fungi and bacteria. Significant biological activities, including antiviral, anti-inflammatory, antitumor, antimicrobial, etc., have been discovered for chromone glycosides, suggesting their potential as drug leads. This review compiles 192 naturally occurring chromone glycosides along with their sources, classification, biological activities, and spectroscopic features. Detailed biosynthetic pathways and chemotaxonomic studies are also described. Extensive spectroscopic features for this class of compounds have been thoroughly discussed, and detailed 13C-NMR data of compounds 1-192, have been added, except for those that have no reported 13C-NMR data.

Efficacy and safety of sotagliflozin in patients with type 2 diabetes and severe renal impairment

AIMS

To assess the efficacy and safety of sotagliflozin, a dual inhibitor of sodium-glucose cotransporter-1 and -2, in adults with type 2 diabetes (T2D) and stage 4 chronic kidney disease (CKD4).

MATERIALS AND METHODS

This 52-week, phase 3, randomized (1:1:1), placebo-controlled trial evaluated sotagliflozin 200 mg and sotagliflozin 400 mg once daily in 277 patients with T2D and estimated glomerular filtration rate (eGFR) 15 to 30 mL/min/1.73 m² . The primary endpoint was glycated haemoglobin (HbA1c) reduction with sotagliflozin 400 mg versus placebo at 26 weeks. A hierarchical statistical testing approach was used.

RESULTS

The baseline mean HbA1c was 65 ± 12 mmol/mol (8.1% ± 1.1%), systolic blood pressure (SBP) was 144 ± 15 mmHg, and eGFR was 24 ± 4 mL/min/1.73m² . Placebo-adjusted changes with sotagliflozin 400 mg were -3 mmol/mol (-0.3%; 95% confidence interval -7 to 0.6 [-0.6 to 0.05]; P = 0.096) and -8 mmol/mol (-0.7%; -13 to -3 [-1.2 to -0.2]; P = 0.003) in HbA1c at Weeks 26 and 52, respectively, -1.5 kg (-3.0 to -0.1) in body weight at Week 26, -5.4 mmHg (-9.4 to -1.3) in SBP at Week 12, and -0.3 mL/min/1.73 m² (-2.1 to 1.6; P = 0.776) in eGFR at Week 52. Over 52 weeks, 11.8%, 5.4% and 3.3% of patients receiving placebo and sotagliflozin 200 and 400 mg, respectively, required rescue therapy for hyperglycaemia. Adverse events (AEs) occurred in 82.8%, 86.2% and 81.1% of patients and serious cardiovascular AEs occurred in 12.9%, 3.2% and 4.4% of patients in the placebo and sotagliflozin 200 and 400 mg groups, respectively.

CONCLUSIONS

After 26 weeks, HbA1c reductions with sotagliflozin were not statistically significant versus placebo in adults with T2D and CKD4. The 52-week safety profile was consistent with results of the SCORED outcomes trial (NCT03242018).

Protective effect of flavonoids from Passiflora edulis Sims on diabetic complications in rats

OBJECTIVES

This study was carried out to evaluate the effects of flavonoids present in leaves of Passiflora edulis fruit on complications induced by diabetes in rats.

METHODS

The extract of P. edulis leaf was obtained by 70% ethanol maceration. From the dry extract, the fractions were obtained by consecutive liquid-liquid partition with hexane, ethyl acetate and n-butanol. The content of isoorientin of ethyl acetate and n-butanol fractions was determined by ultra-performance liquid chromatography coupled with electrospray and triple quadrupole ionization (TQD) analysis in tandem mass spectrometry (UPLC-ESI-Tq-MS). Only Fr-BuOH was used to treat diabetic or not Wistar rats. Biochemical parameters, platelet aggregation and production of reactive species were evaluated.

KEY FINDINGS

The UPLC-ESI-Tq-MS analysis revealed the presence of several flavonoids, among which we identified five possible flavonoids c-heterosides (luteolin-7-O-pyranosyl-3-O-glucoside, apigenin-6-8-di-C-glycoside, apigenin-6-C-arabinoside-8-C-glycoside, isoorientin, isovitexin). The diabetic rats (treated intraperitoneally with alloxan, 150 mg/kg) treated with Fr-BuOH (20 mg/kg/day for 90 days) presented improvement in blood glucose, serum levels of fructosamine, lipid profile and urea. Furthermore, the Fr-BuOH reduced both platelet aggregation and the production of oxidant species in diabetic animals.

CONCLUSIONS

These results suggested that flavonoid C-glycosides present in the Fr-BuOH may be beneficial for the diabetic state, preventing complications induced by diabetes.

Hypoglycemic and hypolipidemic effects of total glycosides of Cistanche tubulosa in diet/streptozotocin-induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cistanche tubulosa (Schrenk) R. Wight (Orobanchaceae) is a frequently prescribed component in many traditional herbal prescriptions which are used to treat diabetes in China. In recent studies, the antidiabetic activity of Cistanche tubulosa extracts have been confirmed. However, no systematic investigation has been reported on the total glycosides of Cistatnche tubulosa (TGCT).

AIM OF THE STUDY

The present study aimed to investigate the hypoglycemic and hypolipidemic effects of TGCT and the potential mechanisms in diet/streptozotocin (STZ)-induced diabetic rats, and to chemically characterize the main constituents of TGCT.

MATERIALS AND METHODS

The major constituents of TGCT were characterized by HPLC/Q-TOF-MS and the analytical quantification was performed with HPLC-DAD. Type 2 diabetic rats were induced by high-fat high-sucrose diet (HFSD) and a single injection of STZ (30 mg/kg). TGCT (50 mg/kg, 100 mg/kg and 200 mg/kg) or metformin (200 mg/kg) were orally administered for 6 weeks. Body weight and calorie intake were monitored throughout the experiment. Fasting plasma glucose (FPG), oral glucose tolerance test (OGTT), area under curve of glucose (AUC-G), glycosylated hemoglobin (HbA1c), fasting insulin, serum C-peptide, glycogen content and insulin sensitivity index were tested. The levels of phosphorylated protein kinase B and phosphorylated glycogen synthase kinase 3β, the activities of hexokinase and pyruvate kinase were assayed. Meanwhile, the changes in serum lipid profiles, superoxide dismutase, glutathione peroxidase, malondialdehyde and inflammatory factors were measured. Histological of pancreas were also evaluated by haematoxylin-eosin stain.

RESULTS

Our investigation revealed the presence of phenylethanoid glycosides (PhGs): echinacoside (500.19 ± 11.52 mg/g), acteoside (19.13 ± 1.44 mg/g) and isoacteoside (141.82 ± 5.78 mg/g) in TGCT. Pharmacological tests indicated that TGCT significantly reversed STZ-induced weight loss (11.1%, 200 mg/kg); decreased FPG (56.4%, 200 mg/kg) and HbA1c (37.4%, 200 mg/kg); ameliorated the OGTT, AUC-G and insulin sensitivity; increased glycogen content (40.8% in liver and 52.6% in muscle, 200 mg/kg) and the activities of carbohydrate metabolizing enzymes; regulated lipid profile changes and the activities of antioxidant enzymes; diminished serum markers of oxidative stress and inflammation in a dose-dependent manner (p < 0.05).

CONCLUSIONS

This study confirmed that TGCT was an effective nutritional agent for ameliorating hyperglycemia and hyperlipidemia in diet/STZ-induced diabetic rats, which might be largely attributed to the activities of TGCT on inhibitions of oxidative stress and inflammation.

Regulating the gut microbiota and SCFAs in the faeces of T2DM rats should be one of antidiabetic mechanisms of mogrosides in the fruits of Siraitia grosvenorii

ETHNOPHARMACOLOGICAL RELEVANCE

The Siraitia grosvenorii fruits extract (SG, in which mogrosides are the main components), considered as a non-nutritional sweetener, has an antidiabetic effect. Our previous studies have confirmed that an extract of mogrosides being rich in triterpene glycosides with 1-3 glucosyl residues, designated as low-polar S. grosvenorii glycosides (L-SGgly), had a significant antidiabetic effect. However, whether the mechanism through impacting on gut microbiota to exert the antidiabetic effect of mogrosides remains unclear.

AIMS OF THE STUDY

To explore the potential mechanism of mogrosides (SG and L-SGgly) on gut microbiota and faecal metabolites in the treatment of diabetes.

STUDY DESIGN AND METHODS

In this study, the effects of SG and L-SGgly on gut microbiota and faecal endogenous metabolites were explored by sequencing the 16S rRNA V3-V4 region of gut microbiota, and detecting with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography quadrupole time-of-flight MS (LC-Q-TOF/MS), respectively. In particular, correlation analyses revealed how these influences affect the anti-hyperglycaemic effect, to give the underlying antidiabetic mechanisms of the mogrosides in S. grosvenorii fruits.

RESULTS

After a 14-day treatment with SG and L-SGgly for type 2 diabetes mellitus (T2DM) rats induced by a high-fat diet (HFD) and streptozotocin (STZ), the disordered gut microbiota in the faeces of T2DM rats were recovered. At the same time, the short-chain fatty acids (SCFAs) concentration significantly increased and the deoxycholic acid and 1β-hydroxycholic acid content decreased in the faeces of T2DM rats. Moreover, correlation analyses provided the evidences that gut microbiota and its metabolites could be the target for exerting the anti-hyperglycaemic effects of SG and L-SGgly. Especially, Elusimicrobium, Lachnospiraceae_UCG-004, acetate, butyrate, and 1β-hydroxycholic acid would be the potential dominant bacteria and biomarkers for SG and L-SGgly in reducing the blood glucose and insulin resistance of T2DM rats.

CONCLUSION

It is the first time that a mechanism of targeting on gut microbiota for the antidiabetic effect of mogrosides in S. grosvenorii fruits has been proposed.

Efficacy of combined angiotensin II receptor blocker with tripterygium glycosides on diabetic nephropathy: A protocol for meta-analysis

BACKGROUND

Several studies have reported good results for angiotensin II receptor blockers (ARB) combined with tripterygium glycosides (TGs) in the treatment of diabetic nephropathy (DN). However, because a small number of cases were included in each study, the statistical power was limited. Therefore, we performed a protocol for meta-analysis to further evaluate the clinical efficacy and safety of combined ARB and TGs in treatment of DN.

METHODS

The protocol was written following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) statement guidelines. We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, Science Direct up to April 2021. Outcome measures were 24-h urinary total protein, urinary albumin excretion rate, serum creatinine, blood urea nitrogen, albumin, hemoglobin A1c, β2-microglobulin and serum glutamic pyruvic transaminase. The risk of bias assessment of the included studies was performed by two authors independently using the tool recommended in the Cochrane Handbook for Systematic Reviews of Interventions (version 5.1.0). We performed meta-analysis using STATA 11.0.

RESULTS

The review will add to the existing literature by showing compelling evidence and improved guidance in clinic settings.

CONCLUSION

The findings will provide helpful evidence for the application of combined ARB and TGs in the treatment of DN.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/ARGE3.

Juglanin protects against high fat diet-induced renal injury by suppressing inflammation and dyslipidemia via regulating NF-κB/HDAC3 signaling

Obesity is an important factor implicated in chronic kidney disease (CKD). Juglanin (Jug) is a natural compound extracted from the crude Polygonumaviculare, showing anti-inflammatory and anti-diabetic effects. However, whether Jug has protective effects against obesity-induced renal injury, little has been investigated. Herein, we attempted to explore the potential of Jug in mediating obesity-induced kidney disease in high fat diet (HFD)-challenged mice. Our results suggested that chronic HFD feeding markedly increased the body weights of mice compared to the ones fed with normal chow diet (NCD), along with significant glucose intolerance and insulin resistance. However, these metabolic disorders induced by HFD were effectively alleviated by Jug treatments in a dose-dependent manner. Moreover, HFD-challenged mice showed apparent histopathological changes in renal tissues with significant collagen accumulation, which were attenuated by Jug supplementation. In addition, Jug treatment decreased the expression levels of kidney injury molecule-1 (KIM-1), while increased nephrin and podocin expression levels in kidney of HFD-challenged mice, improving the renal dysfunction. Furthermore, HFD led to lipid deposition in kidney samples of mice by enhancing abnormal lipid metabolism. In addition, HFD promoted the releases of circulating pro-inflammatory cytokines, and enhanced the renal inflammation by activating nuclear factor-kappa B/histone deacetylase 3 (NF-κB/HDAC3) signaling. HFD-induced dyslipidemia and inflammation were considerably abrogated by Jug administration in mice. The protective effects of Jug against renal injury were confirmed in palmitate (PA)-stimulated HK2 cells in vitro mainly through suppressing the nuclear translocation of NF-κB and HDAC3, repressing inflammation and lipid accumulation eventually. Hence, Jug could ameliorate HFD-induced kidney injury mainly through blocking the NF-κB/HDAC3 nuclear translocation.

Total glycosides and polysaccharides of Cistanche deserticola prevent osteoporosis by activating Wnt/β-catenin signaling pathway in SAMP6 mice

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine Cistanche deserticola Y. C. Ma has effect of "tonifying kidney and strengthening bone". However, the specific active extracts of C. deserticola and mechanisms for treatment of osteoporotic are not clear.

AIM OF THE STUDY

We wanted to identify the effective component extracts of C. deserticola for the treatment of osteoporosis and the potential mechanisms.

MATERIALS AND METHODS

Our group researched the extracts of C. deserticola with anti-osteoporotic activity, including total glycosides (TGs), polysaccharides (PSs), and oligosaccharides (OSs) in senescence accelerated mouse prone 6 (SAMP6) mice. The Goldner's Trichrome, Van Gieson's (VG), Safranin O-Fast Green staining and Von Kossa staining were performed to investigate the bone structure formation and calcium deposits. Serum was collected for detecting biochemical markers. Bone micro-architecture was detected by micro-CT. Expressions of bone morphogenetic protein-2 (BMP-2), osteocalcin (OCN), osteoprotegerin (OPG), receptor activator of nuclear factor-κ B ligand (RANKL), p-glycogen synthetase kinase-3β (p-GSK-3β), and p-β-catenin were analyzed by western blotting and immunohistochemistry.

RESULTS

TGs and PSs ameliorated bone histopathological damages, promoted the formation of new bone, collagenous fiber, and chondrocytes, and accelerated the calcium deposits. Moreover, they remarkable altered the biomarkers of bone turnover and effectively ameliorated bone microarchitecture. The further mechanisms study showed that TGs and PSs significantly decreased the expressions of RANKL, p-β-catenin, as well as up-regulated the expression of BMP-2, OCN, OPG, and p-GSK-3β (Ser9).

CONCLUSION

The findings of this study suggest that TGs and PSs can promote osteoblastogenic bone formation and improve bone microstructure damage in SAMP6 mice, and their therapeutic effect on osteoporosis is via activating Wnt/β-catenin signaling pathway.

Therapeutic potential of russelioside B as anti-arthritic agent in Freund's adjuvant-induced arthritis in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Caralluma species are traditional edible herbs used in folkloric medicine as antidiabetic, antioxidant, antipyretic, antirheumatic, anti-inflammatory and anthelmintic agents. C. quadrangula was selected in this study to document the traditional use of the genus as anti-rheumatic treatment and the possible mechanisms of action.

AIM OF THE STUDY

The higher mortality rates and shorter survival among the patients suffering from rheumatoid arthritis (RA) led to the increased interest on searching for new treatments for RA. Russelioside B (RB), a major pregnane glycoside found in C. quadrangula, was evaluated as a new anti-rheumatic agent.

MATERIALS AND METHODS

The n-butanol fraction of C. quadrangula was chromatographed on a silica gel column to isolate RB. The adjuvant-induced arthritis (AIA) model was established in rats by intradermal injection of complete Freund's adjuvant (CFA) to evaluate its anti-arthritic effect. Ibuprofen was used as a reference drug. Forty rats were randomly divided into 5 groups (n = 8): normal (NOR); CFA model (CFA); ibuprofen, 5 mg/kg; RB, 25 mg/kg and RB, 50 mg/kg. The treatments were initiated from day 16 when AIA model was established and continued up to day 40. Serum diagnostic rheumatoid markers, inflammatory cytokines, oxidative stress biomarkers, cartilage and bone degeneration enzymes were assessed.

RESULTS

RB at 50 mg/kg b. wt., showed significant decreases in the activities of hyaluronidase and β-glucouronidase enzymes as well significant decreases in the levels of proinflammatory cytokines as nuclear factor-kappa-B (NF-κB), tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) compared to the CFA group; 11.04 ± 0.61 pg/mg protein, 4.35 ± 0.25 pg/mg protein, 3.32 ± 0.13 pg/mg protein & 2.75 ± 0.14 pg/mg protein for RB, 50 mg/kg b. wt. group vs. 25.33 ± 2.13 pg/mg protein, 25.65 ± 2.1 pg/mg protein, 22.20 ± 1.34 pg/mg protein & 13.27 ± 1.40 pg/mg protein for the arthritic group, respectively. The total antioxidant capacity (TAC) was significantly restored to normal values in RB, 50 mg/kg treated rats (4.01 ± 0.09 nmol/mL vs. 3.71 ± 0.27 nmol/mL) and the levels of myeloperoxidase (MPO) reduced by 10-folds of the CFA arthritic group. Bone histomorphometry revealed that RB treatment significantly attenuated the CFA-induced bone loss in a dose-dependent manner.

CONCLUSIONS

These findings suggested that the anti-arthritic effect of RB was mediated through the reduction of the rheumatoid markers, anti-inflammatory and antioxidant action, inhibition of cartilage and bone degenerative enzymes as well as attenuation of bone loss and osteoclastogenesis.

Polysaccharides and glycosides from Aralia echinocaulis protect rats from arthritis by modulating the gut microbiota composition

ETHNOPHARMACOLOGICAL RELEVANCE

Aralia echinocaulis has been used in traditional medicines in China and exhibits good effects on rheumatoid arthritis (RA).

AIM OF THE STUDY

Aralia echinocaulis is rich in polysaccharides and glycosides. This study aims to explore the effect of total polysaccharide and glycoside (TPG) from A. echinocaulis on an RA rat model and the role of alterations in gut microbes mediated by TPG.

MATERIALS AND METHODS

In this study, a collagen-induced arthritis (CIA) rat model was constructed and used to evaluate the effects of TPG in vivo. 16S rRNA sequencing was used to detect the changes in the gut microbiota. A cooccurrence analysis was conducted by calculating Spearman's rank correlations. Microbial functions were predicted using PICRUSt with the KEGG and COG databases.

RESULTS

The results showed that TPG from A. echinocaulis could inhibit arthritis, reduce serum IL-1β and TNF-α levels, and improve synovial pathology in the RA rat model but failed to produce the same results in a pseudoaseptic RA rat model. 16S rRNA sequencing verified that TPG could modulate the gut microbiota community structure of RA rats. The cooccurrence analysis found 19 out of the 50 most abundant genera in a cooccurrence network, of which 16 showed a positive correlation and 3 showed a negative correlation. KEGG pathway and COG function analyses found that TPG-induced alterations in the gut microbiota might be correlated with the circulatory system, excretory system, metabolic diseases, signaling molecules and interactions, coenzyme transport and metabolism, and nucleotide transport and metabolism.

CONCLUSIONS

TPG from A. echinocaulis had significant effects on the RA rat model, which are related to the modulation of the gut microbiota. These results are useful to better understanding the mechanisms of TPG in RA.