Dihydromyricetin enhances the osteogenic differentiation of human bone marrow mesenchymal stem cells in vitro partially via the activation of Wnt/β-catenin signaling pathway

Wnt/beta-catenin modulation: A promising frontier in chronic kidney disease management

BACKGROUND

Being amongst the leading factors of death and distress, chronic kidney disease (CKD) has affected around 850 million people globally. The Wnt/β-catenin axis is vital for maintaining kidney homeostasis, from nephron generation to overall management. The β-catenin growth factor is typically not expressed in the adult kidney; however, its expression is found to increase under stress and injury conditions. It is categorised as canonical and non-canonical based on β-catenin availability, which mounts promising targets for ameliorating CKD. Hence, modulation of the Wnt/β-catenin signalling for CKD management is of utmost relevance.

OBJECTIVES

The primary aim of this review is to highlight the significance of targeting Wnt/β-catenin signalling for CKD management.

METHODS

The literature review regarding the role of Wnt/β-catenin signalling and therapies modulating it in CKD was conducted using PubMed, Scopus, Science Direct and Google Scholar.

RESULTS

The current review summarises the pharmacological therapies modulating the Wnt/β-catenin axis in CKD, building upon promising preclinical studies to establish a foundation for clinical studies in the future.

CONCLUSION

Wnt/β-catenin signalling is the evolution's most conserved pathway, which plays a pivotal role in CKD progression. Therapies modulating Wnt/β-catenin signalling have emerged as effective means for alleviating CKD.

Improving osteoinduction and osteogenesis of Ti6Al4V alloy porous scaffold by regulating the pore structure

Titanium alloy scaffolds with a porous structure have attracted much attention in bone defect repair. However, which pore structure is more beneficial to bone defect repair is controversial. In the present research, the Ti6Al4V alloy porous scaffolds with gradient pore sizes were designed and fabricated. The microstructure characterization, tests of mechanical properties, and in vitro and in vivo experiments have been performed to systematically evaluate the effect of pore size on osteoinduction and osteogenesis. The results revealed that the contact angle with water, compressive strength, and elastic modulus of the Ti6Al4V alloy porous scaffolds decreased gradually with the increase of pore size. However, there were obvious drops when the pore size of the porous scaffold was around 600 μm. As the pore size increased, the proliferation and integrin β1 of RAW 264.7 macrophages seeded on Ti6Al4V alloy porous scaffolds increased at first, reaching a maximum value at a pore size of around 600 μm, and then decreased subsequently. The proliferation, integrin β1, and osteogenic gene-related expressions of Bone marrow mesenchymal stem cells (BMSCs) seeded on Ti6Al4V alloy porous scaffolds with different pore sizes all exhibited similar variations which rose with increased pore size firstly, obtaining the maximum value at pore size about 600 μm, and then declined. The in vivo experiments confirmed the in vitro results, and the Ti6Al4V alloy porous scaffold with a pore size of 600 μm possessed the better capability to induce new bone formation. Therefore, for the design of Ti6Al4V alloy with a regular porous scaffold, the surface morphology, porosity, strength, and elastic modulus should be considered systematically, which would determine the capability of osteoinduction and osteogenesis.

Cytotoxicity and Biomineralization Potential of Flavonoids Incorporated into PNVCL Hydrogels

This study aimed to evaluate the effects of flavonoids incorporated into poly(N-vinylcaprolactam) (PNVCL) hydrogel on cell viability and mineralization markers of odontoblast-like cells. MDPC-23 cells were exposed to ampelopsin (AMP), isoquercitrin (ISO), rutin (RUT) and control calcium hydroxide (CH) for evaluation of cell viability, total protein (TP) production, alkaline phosphatase (ALP) activity and mineralized nodule deposition by colorimetric assays. Based on an initial screening, AMP and CH were loaded into PNVCL hydrogels and had their cytotoxicity and effect on mineralization markers determined. Cell viability was above 70% when MDPC-23 cells were treated with AMP, ISO and RUT. AMP showed the highest ALP activity and mineralized nodule deposition. Extracts of PNVCL+AMP and PNVCL+CH in culture medium (at the dilutions of 1/16 and 1/32) did not affect cell viability and stimulated ALP activity and mineralized nodules’ deposition, which were statistically higher than the control in osteogenic medium. In conclusion, AMP and AMP-loaded PNVCL hydrogels were cytocompatible and able to induce bio-mineralization markers in odontoblast-cells.

Microbiological Properties and Cytotoxicity of PNVCL Hydrogels Containing Flavonoids as Intracanal Medication for Endodontic Therapy

This study aimed to evaluate the cytotoxicity and microbiological properties of poly (N-vinylcaprolactam)-PNVCL hydrogels containing flavonoids as intracanal medication for endodontic therapy. Antimicrobial activity of ampelopsin (AMP), isoquercitrin and rutin was determined against Enterococcus faecalis, Actinomyces israelii, Lactobacillus casei, Streptococcus mutans, and Fusobacterium nucleatum by the microdilution method. After synthesis and characterization by rheology, PNVCL hydrogels were loaded with AMP and controls calcium hydroxide (CH) and chlorhexidine (CHX), and determined the compounds release profile. PNVCL+AMP, PNVCL+CH, PNVCL+CHX were evaluated on multi-species biofilms and analyzed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Cytotoxicity was determined after fibroblasts exposure to serial dilutions of AMP and PNVCL hydrogel extracts. AMP was effective against all of the bacteria tested, especially against S. mutans, A. israelli and F. nucleatum. SEM and CLSM analysis showed that PNVCL + AMP caused a significant decrease and disorganization of multi-species biofilms and reduction of intracanal viable cells, superior to the other groups. AMP affected fibroblast viability at concentrations above 0.125 mg/mL, and extracts of PNVCL+AMP showed low cytotoxicity. In conclusion, PNVCL containing AMP demonstrated cytocompatibility and potent effect against multi-species biofilms and could be potential intracanal medication for endodontic purposes.

Dihydromyricetin ameliorates oxygen‑glucose deprivation and re‑oxygenation‑induced injury in HT22 cells by activating the Wnt/β‑catenin signaling pathway

Dihydromyricetin (DMY) is a natural flavonoid that possesses a wide range of pharmacological properties. The aim of the present study was to determine whether DMY could protect against nerve cell injury following ischemic stroke through antioxidant and neuroprotective effects. The effects of DMY on the viability, oxidative stress and apoptosis of HT22 cells following oxygen‑glucose deprivation and re‑oxygenation (OGD/R) were examined using MTT, lactate dehydrogenase (LDH), superoxide (SOD), malondialdehyde (MDA), western blot and TUNEL assays. Furthermore, Wnt/β‑catenin signaling proteins in OGD/R‑stimulated HT22 cells were detected in the presence or absence of DMY. In a separate experiment, the effect of DMY on OGD/R‑induced HT22 cell injury was also observed in the presence of the Wnt/β‑catenin inhibitor, XAV939. The results demonstrated that DMY had no impact on the survival of untreated HT22 cells, although DMY treatment significantly increased cell viability and inhibited cytotoxicity, oxidative stress and apoptosis following OGD/R. In addition, DMY upregulated the expression of Wnt/β‑catenin in OGD/R‑stimulated HT22 cells. In conclusion, DMY protected HT22 cells from OGD/R‑induced oxidative stress and apoptosis, and its effects may be mediated by the activation of the Wnt/β‑catenin signaling pathway.

Dihydromyricetin Exhibits Antitumor Activity in Nasopharyngeal Cancer Cell Through Antagonizing Wnt/β-catenin Signaling

BACKGROUND

Cancer stem cells (CSCs) have been demonstrated to play a vital role in a diversity of biological processes in cancers. With the emergence of new evidence, the important function of CSCs in the formation of multidrug resistance of nasopharyngeal cancer has been demonstrated. Dysregulated Wnt/β-catenin signaling pathway is an important contributor to chemoresistance and maintenance of CSCs-like characteristics. This research aims to investigate comprehensively the function of dihydromyricetin (DMY), a natural flavonoid drug, on the cisplatin (cis) resistance and stem cell properties of nasopharyngeal cancer.

METHODS

In this study, the functional role of DMY in nasopharyngeal cancer progression was comprehensively investigated in vitro and in vivo, and then its relationship with CSCs-like phenotypes and multiple oncogenes was analyzed.

RESULTS

In parallel assays, the growth inhibitory action of cis was enhanced by the addition of DMY in cis-resistant nasopharyngeal cancer cell lines (Hone1/cis and CNE1/cis). Functional assays showed that DMY markedly diminished the stem cell properties of nasopharyngeal cells, such as colony and tumor-sphere formation. In vivo data showed that the growth of Hone1 CSCs formed tumor xenograft was inhibited significantly by the administration of DMY. Additionally, DMY could impair the Wnt/β-catenin signaling pathway and regulate the expression of downstream proteins in nasopharyngeal cancer cells.

CONCLUSIONS

Our study clarified the anti-tumor activity of DMY through blocking the Wnt/β-catenin signaling pathway in nasopharyngeal cancer. Therefore, DMY could be a novel therapeutic agent for nasopharyngeal cancer treatment.

Aberrant canonical Wnt signaling: Phytochemical based modulation

BACKGROUND

Wnt signaling pathway plays a major role during development like gastrulation, axis formation, organ development and organization of body plan development. Wnt signaling aberration has been linked with various disease conditions like osteoporosis, colon cancer, hair follicle tumor, Leukemia, and Alzheimer's disease. Phytochemicals like flavonoid, glycosides, polyphenols, have been reported to directly target the markers of Wnt signaling in different disease models.

PURPOSE

The study deals in detail about the different phytochemical targeting key players of Wnt signaling pathway in diseases like Cancer, Osteoporosis, and Alzheimer's disease. We have focused on the Pharmacological basis of disease alleviation by phytochemical specifically targeting the Wnt signaling markers in this study.

METHODS

The study focused on the published articles from the preclinical rodent and invitro cell line studies related to Wnt signaling and Phytochemicals related to Cancer, Alzheimer's and Osteoporosis. The electronic databases Scopus, Web of Science and Pubmed database were used for the systematic search of literatures from 2005 up to 2019 using keywords Canonical Wnt signaling pathway, Cancer, Alzheimer's disease, Osteoporosis, Phytochemicals. The focus was to identify the target specific modulation of Wnt signaling mediated by phytochemicals.

RESULTS

Approximately 30 phytochemicals of different class have been identified to modulate Wnt signaling pathway acting through Axin, β-catenin translocation, GSK-3β, AKT, Wif-1 in various experimental studies. The down regulation of Wnt signaling is observed in Cancer mostly colorectal cancer, breast cancer mediated through mutations in APC and Axin genes. Different class of Phytochemicals such as flavonoid, glycosides, polyphenol, alkaloids etc. have been found to target Wnt signaling markers and alleviate Cancer. Similarly, Up regulation of Wnt signaling has been reported in Osteoporosis and neurodegenerative disease like Alzheimer's disease.

CONCLUSION

This review highlights the possibility of the Phytochemicals to target Wnt markers and its potential to either activate or deactivate the Wnt signaling pathway. It also describes the challenges in proper targeting of Wnt signaling and the potential risk and consequences of either up regulation or down regulation of the signaling pathway. This article highlights the possibility of Wnt signaling pathway as a therapeutic option in different diseases.

Multitarget and promising role of dihydromyricetin in the treatment of metabolic diseases

Dihydromyricetin (DMY or DHM), also known as ampelopsin, is the main natural flavonol compound extracted from the plant Ampelopsis grossedentata (Hand. -Mazz) W.T. Wang. In recent years, accumulating studies have been conducted to explore the extensive biological functions of DMY, including antitumor, anti-inflammation, organ-protective, and metabolic regulation effects. DMY acts as a potential preventive or therapeutic agent in treating multiple diseases, such as diabetes mellitus, atherosclerosis, nonalcoholic fatty liver disease and osteoporosis. This review article summarizes the preventive and therapeutic potential of DMY in multiple metabolic diseases and the main signaling pathways in which DMY participates to offer a comprehensive understanding and guidance for future studies.

(2R,3R)Dihydromyricetin inhibits osteoclastogenesis and bone loss through scavenging LPS-induced oxidative stress and NF-κB and MAPKs pathways activating

Osteolysis is a serious complication of several chronic inflammatory diseases and is closely associated with a local chronic inflammatory reaction with a variety of causes. However, similarities exist in the mechanisms of their pathological processes. Inflammatory factors and oxidative stress-induced nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) signaling pathways play a center role in bone erosion. Dihydromyricetin (DMY) is a natural compound with anti-inflammatory and antioxidative effect, which are commonly used in chronic pharyngitis and alcohol use disorders. In the current study, we identified that DMY attenuated lipopolysaccharide (LPS)-induced oxidative stress through inhibiting the production of reactive oxygen species (ROS) and nitric oxide (NO), downregulated COX-2 and iNOS, and promoted the activity of the antioxidative system by activating superoxide dismutase (SOD) and Nrf2/HO-1 pathway. To further investigate the underlying mechanism, we found that DMY inhibits osteoclast (OC) differentiation and bone resorption activity through blocking the RANKL-induced activation of the NF-κB and MAPKs signaling pathways and then downregulated c-Fos and NFATc1, which is essential for OC differentiation. Furthermore, DMY inhibited LPS-induced osteolysis in vivo. Collectively, these results indicate that DMY might be a promising prophylactic antiosteoclastic/resorptive agent in preventing or treating bone lysis diseases.

Dihydromyricetin Protects against Bone Loss in Ovariectomized Mice by Suppressing Osteoclast Activity

Dihydromyricetin (DMY), the main flavonoid component of Ampelopsis grossedentata, possesses pharmacological activities useful for treatment of diseases associated with inflammation and oxidative damage. Because osteoclasts are often involved in chronic low-grade systemic inflammation and oxidative damage, we hypothesized that DMY may be an effective treatment for osteoclast-related diseases. The effects of DMY on osteoclast formation and activity were examined in vitro. Female C57BL/6 mice were ovariectomized to mimic menopause-induced bone loss and treated with DMY, and femur samples were subjected to bone structure and histological analysis, serum biochemical indicators were also measured. DMY suppressed the activation of nuclear factor-κB, c-Fos and mitogen-activated protein kinase, and prevented production of reactive oxygen species. DMY decreased expression of osteoclast-specific genes, including Trap, Mmp-9, Cathepsin K, C-Fos, Nfatc1, and Rank. In addition, DMY prevented bone loss and decreased serum levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6, and with a decrease in the ratio between receptor activator of nuclear factor-κB (RANK) ligand (RANKL) and osteoprotegerin (OPG) in vivo. These findings demonstrate that DMY attenuates bone loss and inhibits osteoclast formation and activity through modulation of multiple pathways both upstream and downstream of RANKL signaling. DMY may thus be a useful option for treatment of osteoclast-related diseases such as rheumatoid arthritis and osteoporosis.

The Versatile Effects of Dihydromyricetin in Health

Dihydromyricetin is a flavonoid isolated from Ampelopsis grossedentata, which is traditionally used in China. Dihydromyricetin exhibits health-benefiting activities with minimum adverse effects. Dihydromyricetin has been demonstrated to show antioxidative, anti-inflammatory, anticancer, antimicrobial, cell death-mediating, and lipid and glucose metabolism-regulatory activities. Dihydromyricetin may scavenge ROS to protect against oxidative stress or potentiate ROS generation to counteract cancer cells selectively without any effects on normal cells. However, the low bioavailability of dihydromyricetin limits its potential applications. Recent research has gained positive and promising data. This review will discuss the versatile effects and clinical prospective of dihydromyricetin.