Monotropein exerts protective effects against IL-1β-induced apoptosis and catabolic responses on osteoarthritis chondrocytes

The regulatory role and mechanism of TRPV3 on apoptosis and inflammation in osteoarthritis

Osteoarthritis (OA) is one of the most common forms of degenerative joint disease characterized by persistent pain, inflammation of the joints, and restricted range of motion among the elderly worldwide. Interleukin-1 beta (IL-1β) is increased in the injured joints and contributes to the OA pathobiology by inducing chondrocyte apoptosis and inflammation. Transient receptor potential (TRP) ion channels have recently been reported as potential players in the modulation of apoptosis and inflammation. Here, we aimed to understand the regulatory role and effect of TRPV3 on apoptosis and inflammation in osteoarthritis by using C28/I2 chondrocyte cells as a model. Chondrocytes were transfected with TRPV3-specific siRNA for 24 hours and then stimulated with IL-1β in vitro. Cell cycle progression and apoptosis were evaluated with flow cytometry. The levels of TRPV3, apoptotic (Bax, Caspase-3, and Bcl-2), and inflammatory (iNOS, COX-2) genes were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and confirmed with western blot. Treatment of the C28/I2 chondrocyte cells with IL-1β resulted in the over-expression of TRPV3, induction of apoptosis, and over-expression of inflammation indices. Knockdown of TRPV3 significantly reduced the expression of Bax and Caspase 3 proapoptotic factors while increasing the expression of the Bcl-2 antiapoptotic factor in the mRNA and protein levels in the IL-1β-stimulated cells. Its knockdown also decreased the expression of the inflammatory factors iNOS and COX-2 in mRNA and protein levels, confirming that TRPV3 knockdown hinders apoptosis and inflammation in IL-1β-stimulated chondrocytes. In conclusion, we demonstrated that si-TRPV3 treatment significantly mitigates IL-1β-related effects on the C28/I2 chondrocyte cells. These findings suggested that TRPV3 could be an effective target for the treatment of OA. See also the graphical abstract(Fig. 1).

Monotropein alleviates septic acute liver injury by restricting oxidative stress, inflammation, and apoptosis via the AKT (Ser473)/GSK3β (Ser9)/Fyn/NRF2 pathway

Sepsis-associated acute liver injury (ALI) is a deadly condition resulting from a systemic inflammatory response to liver cell damage and malfunction. Monotropein (MON) belongs to the iris group of compounds extracted from the natural product Mollen dae officinalis radix, which has strong anti-inflammatory and antioxidant pharmacological effects. The purpose of this study was to elucidate the underlying mechanism of MON in the treatment of sepsis ALI. In this study, an in vivo caecal ligation puncture (CLP)-induced ALI model and in vitro LPS-stimulated AML12 cells and RAW264.7 cells model were established. Additionally, a variety of experimental techniques, including CCK8, H&E staining, DHE probe labelling, biochemical, QPCR, and Western blotting and blocking tests, were used to explore the role of MON in ALI. The results showed that MON improved liver morphological abnormalities, oedema, histopathological injury, and elevated ALT and AST, providing a protective effect against ALI. MON reduced CYP2E1 expression, alleviated oxidative stress (downregulation of MDA levels and upregulation of GSH, CAT, and T-AOC levels) and ROS accumulation with the involvement of the NRF2-Keap-1 pathway. MON inhibited inflammation via the TLR4/NF-κB/NLRP3 inflammasome pathway. In addition, it activated the Akt (Ser473)/GSK3β (Ser9)/Fyn pathway and accelerated NRF2 nuclear accumulation; MK-2206 blockade reversed the NRF2 nuclear accumulation and anti-inflammatory function of MON. MON also restricted the mitochondrial apoptosis pathway, a process specifically blocked by MK-2206. In summary, we concluded that MON alleviated septic ALI by restricting oxidative stress, inflammation, and apoptosis via the AKT (Ser473)/GSK3β (Ser9)/Fyn/NRF2 pathway.

Monotropein alleviates acute pulmonary embolism in rats by inhibiting the NF-κB pathway

OBJECTIVE

This study examines the therapeutic potential of monotropein (Mon) in a rat model of acute pulmonary embolism (APE), aiming to elucidate its mechanistic role and provide new insights for APE treatment.

METHODS

Thirty Sprague Dawley (SD) rats were randomly assigned to five groups (n = 6 per group): sham, Mon (40 mg/kg), APE, APE + 20 mg/kg Mon, and APE + 40 mg/kg Mon. APE was induced via autologous thrombus infusion in all groups except sham and Mon-only groups. We assessed blood gas parameters, lung wet/dry weight (W/D) ratio, and oxidative stress markers. Additionally, excised lung tissues underwent evaluation for serum inflammatory factors via ELISA, apoptotic cells via TUNEL assay, and protein expression via Western blot.

RESULTS

Compared to the sham group, APE-induced rats exhibited significantly elevated blood oxygen levels and increased pro-inflammatory factors, including interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-8. Mon treatment effectively mitigated these APE-induced changes, reducing blood oxygen concentration and downregulating IL-1β and TNF-α levels. Furthermore, Mon demonstrated anti-apoptotic effects by decreasing cleaved caspase-3 and Bax protein levels while upregulating Bcl-2 expression. Mon also suppressed nuclear factor-κB (NF-κB) activation by inhibiting the phosphorylation levels of p65/RelA and IκBα proteins, while the total protein level of IκBα was increased with Mon treatment.

CONCLUSION

Mon effectively ameliorated lung tissue injury in APE rats by inhibiting apoptosis, attenuating inflammatory responses, and alleviating oxidative stress. These beneficial effects appear to be mediated through modulation of the NF-κB pathway, suggesting Mon as a promising therapeutic candidate for APE treatment.

Liquid chromatography-mass spectrometry-based strategy for systematic profiling of chemical components and associated quantitative analysis of quality markers in Qi-Wei-Tong-Bi oral liquid

Qi-Wei-Tong-Bi oral liquid (QWTB), a famous Chinese medicine preparation composed of seven crude drugs has a good therapeutic effect on rheumatoid arthritis and is widely used in China. However, its chemical composition and quality control have not been comprehensively and systematically investigated. In this study, high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed for its chemical profiling. As a result, 100 components were chemically characterized. Additionally, high-performance liquid chromatography coupled with a quadrupole linear ion trap mass spectrometry method was developed to simultaneously quantify nine bioactive components (hyperoside, ononin, quercetin, sinomenine, magnoflorine, gallic acid, protocatechuic acid, monotropein, and cyclo-(Pro-Tyr)) in multiple-reaction monitoring mode. After successful validation in terms of linearity, precision, repeatability, and recovery, the assay method was applied for the determination of 10 batches of QWTB. The results showed that QWTB was enriched in sinomenine and magnoflorine with the highest amount up to hundreds or even thousands of µg/mL, while quercetin, ononin, cyclo-(Pro-Tyr), and hyperoside were much lower with the lowest content below 10 µg/mL. This study work would help to reveal the chemical profiling and provide a valuable and reliable approach for quality evaluation and even pharmacodynamic material basis studies of QWTB.

Therapeutic potentials of iridoids derived from Rubiaceae against in vitro and in vivo inflammation: A scoping review

Acute inflammation may develop into chronic, life-threatening inflammation-related diseases if left untreated or if there are persistent triggering factors. Cancer, diabetes mellitus, stroke, cardiovascular diseases, and neurodegenerative disorders are some of the inflammation-related diseases affecting millions of people worldwide. Despite that, conventional medical therapy such as non-steroidal anti-inflammatory drugs (NSAIDs) is associated with serious adverse effects; hence, there is an urgent need for a newer and safer therapeutic alternative from natural sources. Iridoids are naturally occurring heterocyclic monoterpenoids commonly found in Rubiaceae plants. Plant extracts from the Rubiaceae family were demonstrated to have medicinal benefits against neurodegeneration, inflammation, oxidative stress, hyperglycaemia, and cancer. However, the therapeutic effects of natural iridoids derived from Rubiaceae as well as their prospective impacts on inflammation in vitro and in vivo have not been thoroughly explored. The databases of PubMed, Scopus, and Web of Science were searched for pertinent articles in accordance with PRISMA-ScR guidelines. A total of 31 pertinent articles from in vitro and in vivo studies on the anti-inflammatory potentials of iridoids from Rubiaceae were identified. According to current research, genipin, geniposide, and monotropein are the most researched iridoids from Rubiaceae that reduce inflammation. These iridoids primarily act by attenuating inflammatory cytokines and mediators via inhibition of the NF-κB signalling pathway in various disease models. A comprehensive overview of the current research on the anti-inflammatory properties of iridoids from the Rubiaceae family is presented in this review, highlighting the characteristics of the experimental models used as well as the mechanisms of action of these iridoids. To develop an alternative therapeutic agent from iridoids, more studies are needed to elucidate the effects and mechanism of action of iridoids in a wide variety of experimental models as well as in clinical studies pertaining to inflammation-related diseases.

From nature to cancer therapy: Evaluating the Streptomyces clavuligerus secondary metabolites for potential protein kinase inhibitors

The study aimed to evaluate the antioxidant, protein kinase inhibitory (PKIs) potential, cytotoxicity activity of Streptomyces clavuligerus extract. DPPH assay revealed a robust free radical scavenging capacity (IC50 28.90 ± 0.24 µg/mL) of organic extract with a maximum inhibition percentage of 61 ± 1.04%. PKIs assay revealed the formation of a whitish bald zone by S. clavuligerus extracts which indicates the presence of PKIs. The cytotoxicity activity of organic fraction of extract through Sulforhodamine B assay on MCF-7, Hop-62, SiHa, and PC-3 cell lines demonstrated the lowest GI50 value against the MCF-7 cell line followed by the PC-3 cell line, showing potent growth inhibitory potential against human breast cancer and human prostate cancer cell line. HR-LCMS analysis identified multiple secondary metabolites from the organic and aqueous extracts of S. clavuligerus when incubated at 30°C under 200 rpm for 3 days. All the secondary metabolites were elucidated for their potential to inhibit RTKs by molecular docking, molecular dynamic simulation, MM/GBSA calculations, and free energy approach. It revealed the superior inhibitory potential of epirubicin (Epi) and dodecaprenyl phosphate-galacturonic acid (DPGA) against fibroblast growth factors receptor (FGFR). Epi also exhibited excellent inhibitory activity against the platelet-derived growth factor receptor (PDGFR), while DPGA effectively inhibited the vascular endothelial growth factor receptor. Additionally, the presence Epi in S. clavuligerus extract was validated through the HPLC technique. Thus, our findings highlight a superior inhibitory potential of Epi against FGFR and PDGFR RTKs than the FDA-approved drug.

A new iridoid glucoside from the roots of Morinda officinalis

A new iridoid glucoside, moridoside (1), and nine known compounds, asperulosidic acid (2), 6-O-epi-acetylscandoside (3), geniposidic acid (4), 2-hydroxymethylanthraquinone (5), 2-hydroxymethyl-3-hydroxyanthraquinone (6), damnacanthol (7), lucidine-ω-methyl ether (8), 2-hydroxy-1-methoxyanthraquinone (9), and 3,8-dihydroxy-1,2-dimethoxyanthraquinone (10) were isolated from the methanol extract of Morinda officinalis How. roots. Their structural identification was carried out based on the spectroscopic evidence. All compounds were evaluated for their nitric oxide (NO) production inhibitory activities in LPS-stimulated RAW264.7 macrophages. Compounds 5-7 significantly inhibited the production of NO with IC50 values of 28.4, 33.6, and 30.5 μM, respectively.

Monotropein Protects Mesenchymal Stem Cells from Lipopolysaccharide-Induced Impairments and Promotes Fracture Healing in an Ovariectomized Mouse Model

Monotropein is one of the active ingredients in Morinda Officinalis, which has been used for the treatment in multiple bone and joint diseases. This study aimed to observe the in vitro effects of Monotropein on osteogenic differentiation of lipopolysaccharide treated bone marrow mesenchymal stem cells (bMSCs), and the in vivo effects of local application of Monotropein on bone fracture healing in ovariectomized mice. Lipopolysaccharide was used to set up the inflammatory model in bMSCs, which were treated by Monotropein. Molecular docking analysis was performed to evaluate the potential interaction between Monotropein and p65. Transverse fractures of middle tibias were established in ovariectomized mice, and Monotropein was locally applied to the fracture site using injectable hydrogel. Monotropein enhanced the ability of primary bMSCs in chondro-osteogenic differentiation. Furthermore, Monotropein rescued lipopolysaccharide-induced osteogenic differentiation impairment and inhibited lipopolysaccharide-induced p65 phosphorylation in primary bMSCs. Docking analysis showed that the binding activity of Monotropein and p65/14-3-3 complex is stronger than the selective inhibitor of NF-κB (p65), DP-005. Local application of Monotropein partially rescued the decreased bone mass and biomechanical properties of callus or healed tibias in ovariectomized mice. The expressions of Runx2, Osterix and Collagen I in the 2-week callus were partially restored in Monotropein-treated ovariectomized mice. Taking together, local application of Monotropein promoted fracture healing in ovariectomized mice. Inhibition of p65 phosphorylation and enhancement in osteogenesis of mesenchymal stem cells could be partial of the effective mechanisms.

Monotropein alleviates sepsis-elicited acute lung injury via the NF-κB pathway

OBJECTIVES

To address the effect and mechanism of Monotropein (Mon) on sepsis-induced acute lung injury (ALI).

METHODS

ALI model was established by lipopolysaccharide (LPS)-stimulated mouse lung epithelial cell lines (MLE-12) and cecal ligation and puncture (CLP)-treated mice, respectively. The function of Mon was examined by cell counting kit-8 (CCK-8), pathological staining, the pulmonary function examination, flow cytometry, enzyme-linked immunosorbent assay, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labellingand western blot.

RESULTS

Mon increased the LPS-reduced viability but decreased the LPS-evoked apoptosis rate in MLE-12 cells. Mon suppressed the concentrations and protein expressions of proinflammatory factors, and the expressions of fibrosis-related proteins in LPS-challenged MLE-12 cells compared with LPS treatment alone. Mechanically, Mon downregulated the levels of NF-κB pathway, which was confirmed with the application of the receptor activator of nuclear factor-κB ligand (RANKL). Correspondingly, RANKL reversed the ameliorative effect of Mon on the proliferation, apoptosis, inflammation and fibrosis. Moreover, Mon improved the pathological manifestations, apoptosis, the W/D ratio and pulmonary function indicators in CLP-treated mice. Consistently, Mon attenuated inflammation, fibrosis and NF-κB pathway in CLP-treated mice.

CONCLUSION

Mon inhibited apoptosis, inflammation and fibrosis to alleviate sepsis-evoked ALI via the NF-κB pathway.

In vitro and in vivo anti-inflammatory activity of Cupressus torulosa D.DON needles extract and its chemical characterization

ETHNOPHARMACOLOGICAL RELEVANCE

Cupressus torulosa (family Cupressaceae), widely distributed in the north western Himalayan region of India, is a coniferous aromatic tree with various traditional uses of its aerial parts. Its needles have been used for anti-inflammatory, anticonvulsant, antimicrobial, and wound-healing properties.

AIM OF THE STUDY

The study aimed at investigating the previously unknown anti-inflammatory activity of the hydromethanolic extract of the needles employing in vitro and in vivo assays and scientifically validate traditional claim of their use in treatment of inflammation. Chemical characterization of the extract with the aid of UPLCQTOFMS was also of interest.

MATERIALS AND METHODS

C. torulosa needles were first defatted with hexane and sequentially extracted with chloroform and 25% aqueous methanol (AM). Since the presence of phenolics (TPCs, 208.21 ± 0.95 mg GAE/g needles) and flavonoids (TFCs, 84.61 ± 1.21 mg QE/g needles) was observed in the AM extract only, it was chosen for biological and chemical examinations. Acute toxicity of the AM extract on female mice was evaluated following the OECD guideline 423. In vitro anti-inflammatory activity of the AM extract was examined using egg albumin denaturation assay while carrageenan-induced paw edema and formalin-induced paw edema models at doses of 100, 200 and 400 mg/kg po were used to determine the in vivo activity of the AM extract on Wistar rats of either sex. The components of the AM extract were analyzed by UPLC-QTOF-MS method using non-targeted metabolomics approach.

RESULTS

AM extract was found to be non-toxic at 2000 mg/kg b.w. with no signs of abnormal locomotion, seizures and writhing. The extract demonstrated promising in vitro anti-inflammatory activity (IC₅₀ 160.01 μg/mL) compared to standard diclofenac sodium (IC₅₀ 73.94 μg/mL) in egg albumin denaturation assay. In carrageenan-induced paw edema and formalin-induced paw edema tests the extract showed significant anti- inflammatory activity (57.28% and 51.04% inhibition of paw edema, respectively) at the dose of 400 mg/kg p.o. after 4 h in comparison to the standard diclofenac sodium which displayed 61.39% and 52.90% inhibition, respectively, at the dose of 10 mg/kg p.o. after 4 h in these models. A total of 63 chemical constituents, majority of them being phenolics, were found in the AM extract of the needles. Two compounds namely monotropein (iridoid glycoside), (±)12-HETE (eicosanoid) and fraxin (coumarin glycoside) were reported to have anti-inflammatory effect.

CONCLUSIONS

For the first time our study demonstrated that hydro-methanolic extract of C. torulosa needles exhibit anti-inflammatory activity thereby supporting their traditional use in the treatment of inflammatory disorders. UPLCQTOFMS assisted chemical profile of the extract was also unveiled.

Monotropein attenuates apoptosis and pyroptosis in chondrocytes and alleviates osteoarthritis progression in mice

BACKGROUND

Osteoarthritis (OA) is a chronic degenerative joint disease characterized by loss of joint function, which seriously reduces the quality of life of the elderly and imposes a heavy socioeconomic burden worldwide. Monotropein (MON), the main active ingredient of Morinda officinalis F.C. How, has exhibited therapeutic effects in different disease models. However, its potential effects on chondrocytes in an arthritic model remain unclear. This study aimed to evaluate the effects of MON in chondrocytes and a mouse model of OA, and explore the potential mechanisms.

MATERIALS AND METHODS

Murine primary chondrocytes were pretreated with 10 ng/ml interleukin (IL)-1β for 24 h to establish an in vitro model of OA, and then treated with different concentrations of MON (0, 25, 50 and 100 μM) for 24 h. The proliferation of the chondrocytes was assayed using ethynyl-deoxyuridine (EdU) staining. Immunofluorescence staining, western blotting and TUNEL staining were performed to assess the effects of MON on cartilage matrix degradation, apoptosis and pyroptosis. The mouse model of OA was constructed by surgical destabilization of the medial meniscus (DMM), and the animals were randomly divided into the sham-operated, OA and OA + MON groups. Following OA induction, the mice were given intraarticular injection of 100 μM MON or equal volume of normal saline twice a week for 8 weeks. The effects of MON on cartilage matrix degradation, apoptosis and pyroptosis were assessed as indicated.

RESULTS

MON significantly accelerated the proliferation of chondrocytes, and inhibited cartilage matrix degradation, apoptosis and pyroptosis in the IL-1β-stimulated cells by blocking the nuclear factor-kappa B (NF-κB) signaling pathway. In the mouse model as well, MON treatment alleviated OA progression and promoted cartilage repair by inhibiting cartilage matrix degradation, and chondrocyte apoptosis and pyroptosis through the inactivation of the NF-κB signaling pathway. Furthermore, the MON-treated arthritic mice exhibited better articular tissue morphology and lower OARSI scores.

CONCLUSIONS

MON alleviated OA progression by inhibiting cartilage matrix degradation, and the apoptosis and pyroptosis of chondrocytes via NF-κB pathway inactivation, and is a promising alternative for the treatment of OA.

Knowledge mapping of autophagy in osteoarthritis from 2004 to 2022: A bibliometric analysis

Background

Autophagy in osteoarthritis (OA) has become an active area of research with substantial value and potential. Nevertheless, few bibliometric studies have systematically analyzed the available research in the field. The main goal of this study was to map the available literature on the role of autophagy in OA and identify global research hotspots and trends.

Methods

The Web of Science Core Collection and Scopus databases were interrogated for studies of autophagy in OA published between 2004 and 2022. Microsoft Excel, VOSviewer and CiteSpace software were used to analyze and visualize the number of publications and associated citations, and reveal global research hotspots and trends in the autophagy in OA field.

Results

732 outputs published by 329 institutions from 55 countries/regions were included in this study. From 2004 to 2022, the number of publications increased. China produced the most publications (n=456), prior to the USA (n=115), South Korea (n=33), and Japan (n=27). Scripps Research Institute (n=26) was the most productive institution. Martin Lotz (n=30) was the highest output author, while Caramés B (n=302) was the highest output author. Osteoarthritis and Cartilage was the most prolific and most co-cited journal. Currently, the autophagy in OA research hotspots include chondrocyte, transforming growth factor beta 1 (TGF-β1), inflammatory response, stress, and mitophagy. The emerging research trends in this field are AMPK, macrophage, senescence, apoptosis, tougu xiaotong capsule (TXC), green tea extract, rapamycin, and dexamethasone. Novel drugs targeting specific molecule such as TGF-β and AMPK have shown therapeutic potential but are still in the preclinical stage of development.

Conclusions

Research on the role of autophagy in OA is flourishing. Martin Lotz, Beatriz Caramés, and Osteoarthritis and Cartilage have made outstanding contributions to the field. Prior studies of OA autophagy mainly focused on mechanisms underlying OA and autophagy, including AMPK, macrophages, TGF-β1, inflammatory response, stress, and mitophagy. Emerging research trends, however, are centered around the relationship between autophagy, apoptosis, and senescence, as well as drug candidates such as TXC and green tea extract. The development of new targeted drugs that enhance or restore autophagic activity is a promising strategy for the treatment of OA.

In Vitro Neurotrophic Properties and Structural Characterization of a New Polysaccharide LTC-1 from Pyrola corbieri Levl (Luticao)

Pyrola corbieri Levl has been used to strengthen bones and nourish the kidney (the kidney governs the bone and is beneficial to the brain) by the local Miao people in China. However, the functional components and neurotrophic activity have not been reported. A new acidic homogeneous heteropolysaccharide named LTC-1 was obtained and characterized by periodate oxidation, Smith degradation, partial acid hydrolysis, GC-MS spectrometry, methylation analysis, and Fourier transform infrared spectroscopy, and its molecular weight was 3239 Da. The content of mannuronic acid (Man A) in LTC-1 was 46%, and the neutral sugar was composed of L-rhamnose (L-Rha), L-arabinose (L-Ara), D-xylose (D-Xyl), D-mannose (D-Man), D-glucose (D-Glc) and D-galactose (D-Gal) with a molar ratio of 1.00:3.63:0.86:1.30:6.97:1.30. The main chain of LTC-1 was composed of Glc, Gal, Man, Man A and the branched chain Ara, Glc, Gal. The terminal residues were composed of Glc and Gal. The main chain and branched chains were linked by (1→5)-linked-Ara, (1→3)-linked-Glc, (1→4)-linked-Glc, (1→6)-linked-Glc, (1→3)-linked-Gal, (1→6)-linked-Gal, (1→3, 6)-linked-Man and ManA. Meanwhile, neurotrophic activity was evaluated through PC12 and primary hippocampal neuronal cell models. LTC-1 exhibited neurotrophic activity in a concentration-dependent manner, which significantly induced the differentiation of PC12 cells, promoted the neurite outgrowth of PC12 cells, enhanced the formation of the web architecture of dendrites, and increased the density of dendritic spines in hippocampal neurons and the expression of PSD-95. These results displayed significant neurotrophic factor-like activity of LTC-1, which suggests that LTC-1 is a potential treatment option for neurodegenerative diseases.

Molecular mechanisms of the Guizhi decoction on osteoarthritis based on an integrated network pharmacology and RNA sequencing approach with experimental validation

Background: Our aim was to determine the potential pharmacological mechanisms of the Guizhi decoction (GZD) in the treatment of osteoarthritis (OA) through an integrated approach of network pharmacological analyses, RNA sequencing (RNA-seq), and experimental validation. Methods: The quality control and identification of bioactive compounds of the GZD were carried out by using ultra-performance liquid chromatography (UPLC), and their OA-related genes were identified through overlapping traditional Chinese medicine systems pharmacology database (TCMSP), DrugBank and SEA Search Server databases, and GeneCards. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were implemented after constructing the component-target network. RNA-seq was used to screen differentially expressed genes (DEGs) under intervention conditions with and without the GZD in vitro. The crossover signaling pathways between RNA-seq and network pharmacology were then analyzed. Accordingly, protein-protein interaction (PPI) networks, GO, and KEGG analysis were performed using the Cytoscape, STRING, or DAVID database. The OA rat model was established to further verify the pharmacological effects in vivo. Hematoxylin-eosin (H&E) and safranin O/fast green (S-O) staining were used to grade the histopathological features of the cartilage. We verified the mRNA and protein expressions of the key targets related to the TNF signaling pathways in vivo and in vitro by qPCR, Western blotting (WB), and immunofluorescence assay. In addition, we also detected inflammatory cytokines in the rat serum by Luminex liquid suspension chip, which included tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). Results: Eighteen compounds and 373 targets of the GZD were identified. A total of 2,356 OA-related genes were obtained from the GeneCards database. A total of three hub active ingredients of quercetin, kaempferol, and beta-sitosterol were determined, while 166 target genes associated with OA were finally overlapped. The RNA-seq analysis revealed 1,426 DEGs. In the KEGG intersection between network pharmacology and RNA-seq analysis, the closest screening relevant to GZD treatment was the TNF signaling pathway, of which TNF, IL-6, and IL-1β were classified as hub genes. In consistent, H&E and S-O staining of the rat model showed that GZD could attenuate cartilage degradation. When compared with the OA group in vivo and in vitro, the mRNA levels of TNF-α, IL-1β, IL-6, matrix metalloproteinase 3 (MMP3), and matrix metalloproteinase 9 (MMP9) were all downregulated in the GZD group (all p < 0.05). The expression levels of anabolic proteins (Col2α1 and SOX9) were all higher in the GZD group than in the OA group (p < 0.05), while the expression levels of the catabolic proteins (MMP9 and COX-2) and TNF-α in the GZD group were significantly lower than those in the OA group (p < 0.05). In addition, the expression levels of TNF, IL-6, and IL-1β were upregulated in the OA group, while the GZD group prevented such aberrations (p < 0.01). Conclusion: The present study reveals that the mechanism of the GZD against OA may be related to the regulation of the TNF signaling pathway and inhibition of inflammatory response.

Monotropein attenuates doxorubicin-induced oxidative stress, inflammation, and arrhythmia via the AKT signal pathway

As a glycoside iridoid, monotropein (MON) has a wide range of pharmacological properties, including anti-inflammatory, antioxidant, and anti-apoptotic effects. However, few studies have investigated MON's cardiovascular protective effects. Therefore, this study aimed to explore the role of MON in doxorubicin (DOX)-induced cardiotoxicity. To establish the myocardial toxicity model, mice were intraperitoneally injected with DOX. After admimistration of DOX, myocardial injury markers were increased, cardiac function was reduced, and pathological changes were observed in the myocardium, indicating successful construction of the myocardial injury model. Our study showed that MON treatment mitigated DOX-induced myocardial damage and improved cardiac dysfunction. In addition, DOX-treated mice displayed higher levels of inflammation and oxidative stress, while MON treatment also reversed these pathological changes. Moreover, DOX-treated mice were more susceptible to ventricular fibrillation, whereas MON reduced ventricular fibrillation incidence. Further studies have shown that MON could reverse DOX-induced inhibition of the AKT signaling pathway. Besides, the application of AKT inhibitor could partially abolish MON's cardioprotective effects. To conclude, this study demonstrated the ability of MON to reduce DOX-induced myocardial damage, cardiac dysfunction, inflammation, and oxidative stress, as well as ventricular fibrillation risk. These may attributable to the activation of the AKT pathway.

Monotropein: A comprehensive review of biosynthesis, physicochemical properties, pharmacokinetics, and pharmacology

Monotropein, a principal natural compound in iridoid glycosides extracted from Morindae officinalis radix, has potent pharmacological activities. To understand and utilize monotropein, we systematically summarized the studies on monotropein, including its biosynthetic pathway, physicochemical properties, pharmacokinetics, and pharmacology. Interestingly, we found that the multiple bioactivities of monotropein, such as anti-osteoporosis, anti-inflammation, anti-oxidation, anti-nociception, and hepatic or renal protection, are closely associated with its capability of downregulating the nuclear factor-κB signaling pathway, inhibiting the mitogen-activated protein kinase signaling pathway, attenuating the activation of nuclear factor E2-related factor 2/heme oxygenase-1 signaling pathway, and regulating the mammalian target of rapamycin/autophagy signaling pathway. However, the clinically therapeutic effects and the potential problems need to be addressed. This review highlights the current research progress on monotropein, which provides a reference for further investigation of monotropein.

Endophytic Diaporthe Associated with Morinda officinalis in China

Diaporthe species are endophytes, pathogens, and saprobes with a wide host range worldwide. However, little is known about endophytic Diaporthe species associated with Morinda officinalis. In the present study, 48 endophytic Diaporthe isolates were obtained from cultivated M. officinalis in Deqing, Guangdong Province, China. The nuclear ribosomal internal transcribed spacer (ITS), partial sequences of translation elongation factor 1-α (tef1-α), partial calmodulin (cal), histone H3 (his), and Beta-tubulin (β-tubulin) gene regions were sequenced and employed to construct phylogenetic trees. Based on morphology and combined multigene phylogeny, 12 Diaporthe species were identified, including five new species of Diaporthe longiconidialis, D. megabiguttulata, D. morindendophytica, D. morindae, and D. zhaoqingensis. This is the first report of Diaporthe chongqingensis, D. guangxiensis, D. heliconiae, D. siamensis, D. unshiuensis, and D. xishuangbanica on M. officinalis. This study provides the first intensive study of endophytic Diaporthe species on M. officinalis in China. These results will improve the current knowledge of Diaporthe species associated with this traditional medicinal plant. Furthermore, results from this study will help to understand the potential pathogens and biocontrol agents from M. officinalis and to develop a disease management platform.

Monotropein Improves Dexamethasone-Induced Muscle Atrophy via the AKT/mTOR/FOXO3a Signaling Pathways

The present study aimed to investigate the effects of monotropein (MON) on improving dexamethasone (DEX)-induced muscle atrophy in mice and C2C12 mouse skeletal muscle cells. The body weights, grip strengths, and muscle weights of mice were assessed. The histological change in the gastrocnemius tissues was also observed through H&E staining. The expression of myosin heavy chain (MyHC), muscle ring finger 1 (MuRF1), and muscle atrophy F-box (Atrogin1) and the phosphorylation of AKT, mTOR, and FOXO3a in the muscle tissues of mice and C2C12 myotubes were analyzed using Western blotting. MON improved muscle atrophy in mice and C2C12 myotubes by regulating catabolic states via the AKT/mTOR/FOXO3a signaling pathways, and enhanced muscle function by the increases of muscle mass and strength in mice. This suggests that MON could be used for the prevention and treatment of muscle atrophy in patients.

Chemical Fingerprint Analysis and Quantitative Analysis of Saccharides in Morindae Officinalis Radix by HPLC-ELSD

A method based on high performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) was developed for the quantitative analysis of three active compounds and chemical fingerprint analyses of saccharides in Morindae officinalis radix. Ten batches of Morindae officinalis radix were collected from different plantations in the Guangdong region of China and used to establish the fingerprint. The samples were separated with a COSMOIL Sugar-D column (4.6 mm × 250 mm, 5 μm) by using gradient elution with water (A) and acetonitrile (B). In addition, Trapped-Ion-Mobility (tims) Time-Of-Flight (tims TOF) was used to identify saccharides of Morindae officinalis radix. Fingerprint chromatogram presented 26 common characteristic peaks in the roots of Morinda officinalis How, and the similarities were more than 0.926. In quantitative analysis, the three compounds showed good regression (r = 0.9995-0.9998) within the test ranges, and the recoveries of the method were in the range of 96.7-101.7%. The contents of sucrose, kestose and nystose in all samples were determined as 1.21-7.92%, 1.02-3.37%, and 2.38-6.55%, respectively. The developed HPLC fingerprint method is reliable and was validated for the quality control and identification of Morindae officinalis radix and can be successfully used to assess the quality of Morindae officinalis radix.

Bugan Rongjin decoction alleviates inflammation and oxidative stress to treat the postmenopausal knee osteoarthritis through Wnt signaling pathway

BACKGROUND

Traditional Chinese medicine has been found effective for the therapy of knee osteoarthritis (KOA). This study was aimed at investigating the underlying mechanism of Bugan Rongjin decoction (BGRJ) in treating the postmenopausal KOA.

RESULTS

Ovariectomized rat model of KOA and LPS-induced chondrocytes were successfully constructed for in vivo and in vitro model of postmenopausal KOA. X-ray and hematoxylin-eosin (H&E) staining showed that BGRJ alleviated pathological damage of articular cartilage in OVX rats with KOA. In addition, BGRJ inhibited inflammation and oxidative stress through decreasing the levels of serum IL-6, IL-1β, TNF-α and NO and regulated Wnt signaling pathway by downregulating the expression of Wnt5a and β-catenin and upregulating the expression of Sox9 and Collagen II in cartilage tissue, detected by immunohistochemistry (IHC) and western blot analysis. Furthermore, Wnt5a silencing reduced the apoptosis of LPS-induced ADTC5 cells, which was further suppressed by the combination of downregulation of Wnt5a and BGRJ.

CONCLUSIONS

In summary, BGRJ alleviates inflammation and oxidative stress to treat the postmenopausal KOA through Wnt signaling pathway.

Research Progress on the Antiosteoarthritic Mechanism of Action of Natural Products

Background

Osteoarthritis (OA) is a clinical joint degenerative disease, the pathogenic factors of which include age, obesity, and mechanical injury. Its main pathological features include cartilage loss, narrowing of joint space, and osteophyte formation. At present, there are a variety of treatment methods for OA. Natural products, which are gradually being applied in the treatment of OA, are advantageous as they present with low toxicity and low costs and act on multiple targets.

Methods

The terms “natural products,” “osteoarthritis,” and “chondrocytes” were searched in PubMed to screen the related literature in the recent 10 years.

Results

We comprehensively introduced 62 published papers on 48 natural products involving 6, 3, 5, 12, 4, and 5 kinds of terpenoids, polysaccharides, polyphenols, flavonoids, alkaloids, and saponins, respectively (and others).

Conclusion

The mechanisms of their anti-OA action mainly involve reducing the production of inflammatory factors, reducing oxidative stress, regulating the metabolism of chondrocytes, promoting the proliferation of chondrocytes, or inhibiting chondrocyte apoptosis. This article summarizes the anti-OA activity of natural products in the last 10 years and provides candidate monomers for further study for use in OA treatment.

PPARγ Attenuates Interleukin-1β-Induced Cell Apoptosis by Inhibiting NOX2/ROS/p38MAPK Activation in Osteoarthritis Chondrocytes

INTRODUCTION

Reactive oxygen species (ROS) induced by extracellular cytokines trigger the expression of inflammatory mediators in osteoarthritis (OA) chondrocyte. Peroxisome proliferator-activated receptor gamma (PPARγ) exerts an anti-inflammatory effect. The aim of this study was to elucidate the role of PPARγ in interleukin-1β- (IL-1β-) induced cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) expression through ROS generation in OA chondrocytes.

METHODS

IL-1β-induced ROS generation and chondrocyte apoptosis were determined by flow cytometry. Contents of NADPH oxidase (NOX), caspase-3, and caspase-9 were evaluated by biochemical detection. The involvement of NOX2 and mitogen-activated protein kinases (MAPKs) in IL-1β-induced COX-2 and PGE2 expression was investigated using pharmacologic inhibitors and further analyzed by western blotting. Activation of PPARγ was performed by using a pharmacologic agonist and was analyzed by western blotting.

RESULTS

IL-1β-induced COX-2 and PGE2 expression was mediated through NOX2 activation/ROS production, which could be attenuated by N-acetylcysteine (NAC; a scavenger of ROS), GW1929 (PPARγ agonist), DPI (diphenyleneiodonium chloride, NOX2 inhibitor), SB203580 (p38MAPK inhibitor), PD98059 (extracellular signal-regulated kinase, ERK inhibitor), and SP600125 (c-Jun N-terminal kinase, JNK inhibitor). ROS activated p38MAPK to enter the nucleus, which was attenuated by PPARγ.

CONCLUSION

In OA chondrocytes, IL-1β induced COX-2 and PGE2 expression via activation of NOX2, which led to ROS production and MAPK activation. The activation of PPARγ exerted protective roles in the pathogenesis of OA.

Kaempferia parviflora Extract Alleviated Rat Arthritis, Exerted Chondroprotective Properties In Vitro, and Reduced Expression of Genes Associated with Inflammatory Arthritis

Kaempferia parviflora Wall. ex Baker (KP) has been reported to attenuate cartilage destruction in rat model of osteoarthritis. Previously, we demonstrated that KP rhizome extract and its active components effectively suppressed mechanisms associated with RA in SW982 cells. Here, we further evaluated the anti-arthritis potential of KP extract by using multi-level models, including a complete Freund’s adjuvant-induced arthritis and a cartilage explant culture model, and to investigate the effects of KP extract and its major components on related gene expressions and underlying mechanisms within cells. In arthritis rats, the KP extract reduced arthritis indexes, with no significant changes in biological parameters. In the cartilage explant model, the KP extract exerted chondroprotective potential by suppressing sulfated glycosaminoglycans release while preserving high accumulation of proteoglycans. In human chondrocyte cell line, a mixture of the major components equal to their amounts in KP extract showed strong suppression the expression of genes-associated inflammatory joint disease similar to that of the extract. Additionally, KP extract significantly suppressed NF-κB and MAPK signaling pathways. The suppressing expression of necroptosis genes and promoted anti-apoptosis were also found. Collectively, these results provided supportive evidence of the anti-arthritis properties of KP extract, which are associated with its three major components.

Monotropein alleviates H2O2‑induced inflammation, oxidative stress and apoptosis via NF‑κB/AP‑1 signaling

Aging is a major risk factor in cardiovascular disease (CVD). Oxidative stress and inflammation are involved in the pathogenesis of CVD, and are closely associated with senescent vascular endothelial cells. Monotropein (Mtp) exerts various bioactive roles, including anti‑inflammatory and antioxidative effects. The aim of the present study was to investigate the function of Mtp in senescent endothelial cells. An MTT assay was performed to evaluate the influence of Mtp on H2O2‑stimulated human umbilical vein endothelial cells (HUVECs). Senescent cells were assessed by determining the expression of senescence‑associated β‑galactosidase, high mobility group AT‑hook 1 and DNA damage marker γ‑H2A.X variant histone. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH‑Px) and proinflammatory cytokine concentrations were estimated using assay kits to evaluate the levels of oxidative stress and inflammation in HUVECs. The TUNEL assay was performed to identify apoptotic cells. Furthermore, the expression levels of endothelial cell adhesion factors, NF‑κB, activator protein‑1 (AP‑1) and apoptotic proteins were determined via western blotting. Mtp enhanced HUVEC viability following H2O2 stimulation. H2O2‑mediated increases in MDA, proinflammatory cytokine and endothelial cell adhesion factor levels were decreased by Mtp treatment, whereas Mtp reversed H2O2‑mediated downregulation of SOD and GSH‑Px activity. Furthermore, Mtp inhibited cell apoptosis, NF‑κB activation and AP‑1 expression in H2O2‑stimulated HUVECs; however, NF‑κB activator counteracted the anti‑inflammatory, antioxidative and antiapoptotic effects of Mtp. The present study indicated that Mtp ameliorated H2O2‑induced inflammation and oxidative stress potentially by regulating NF‑κB/AP‑1.

Treatment of tibial dyschondroplasia with traditional Chinese medicines: "Lesson and future directions"

Tibial dyschondroplasia (TD) is a metabolic tibiotarsal bone disease in rapidly growing birds throughout the world, which is characterized by gait disorders, reduced growth, and in an unrecoverable lameness in many cases. The short production cycle in chickens, long metabolism cycle in most of the drugs with the severe drug residue, and high treatment cost severely restrict the enthusiasm for the treatment of TD. Traditional Chinese medicine (TCM) has been used for the prevention, treatment, and cure of avian bone diseases. Previously, a couple of traditional Chinese medicines has been reported being useful in treating TD. This review will discuss the TCM used in TD and the alternative TCM to treat TD. Selecting a TCM approach and its pharmacologic effects on TD chickens mainly focused on the differentiation, proliferation, and apoptosis of chondrocytes, angiogenesis, matrix metabolism, oxidative damage, cytokines, and calcification of cartilage in tibia.

Molecular Targets of Natural Products for Chondroprotection in Destructive Joint Diseases

Osteoarthritis (OA) is the most common type of arthritis that occurs in an aged population. It affects any joints in the body and degenerates the articular cartilage and the subchondral bone. Despite the pathophysiology of OA being different, cartilage resorption is still a symbol of osteoarthritis. Matrix metalloproteinases (MMPs) are important proteolytic enzymes that degrade extra-cellular matrix proteins (ECM) in the body. MMPs contribute to the turnover of cartilage and its break down; their levels have increased in the joint tissues of OA patients. Application of chondroprotective drugs neutralize the activities of MMPs. Natural products derived from herbs and plants developed as traditional medicine have been paid attention to, due to their potential biological effects. The therapeutic value of natural products in OA has increased in reputation due to their clinical impact and insignificant side effects. Several MMPs inhibitor have been used as therapeutic drugs, for a long time. Recently, different types of compounds were reviewed for their biological activities. In this review, we summarize numerous natural products for the development of MMPs inhibitors in arthritic diseases and describe the major signaling targets that were involved for the treatments of these destructive joint diseases.

NEAT1/miR-193a-3p/SOX5 axis regulates cartilage matrix degradation in human osteoarthritis

Long non-coding RNAs (lncRNAs) were reported to be involved in the progression of osteoarthritis (OA). The aim of this work was to explore the functional role of lncRNA nuclear-enriched abundant transcript 1 (NEAT1) in OA. Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) was employed to analyze the expression of microRNA (miR-193a)-3p, NEAT1, and sex-determining region Y-box protein 5 (SOX5), as well as the levels of pro-inflammatory cytokines interleukin-6 (IL-6), IL-1β, tumor necrosis factor-α (TNF-α), and IL-8 in OA cartilage tissue and chondrocytes. In addition, flow cytometry was used to measure the apoptosis of chondrocytes. The protein levels of extracellular matrix ACAN, collagen type II α1 chain (Col2a1), matrix metalloproteinase-3 (MMP-3), MMP-13, a disintegrin, and metalloproteinase with thrombospondin motifs (ADAMTS)-5 and SOX5 were determined using western blot analysis. Dual-luciferase reporter assay was performed to determine the target relationship among NEAT1, miR-193a-3p, and SOX5. We found that miR-193a-3p expression was downregulated, while NEAT1 and SOX5 were upregulated in OA cartilage tissue and chondrocytes. Both upregulation of miR-193a-3p and knockdown of NEAT1 suppressed inflammation, apoptosis, and reduced the protein levels of MMP-3, MMP-13, and ADAMTS-5, while elevating ACAN and Col2a1 expression in chondrocytes. NEAT1 targeted miR-193a-3p, and SOX5 was targeted by miR-193a-3p. Silencing of miR-193a-3p reversed the NEAT1 knockdown-mediated effect on the inflammation, apoptosis, and production of the extracellular matrix. The introduction of SOX5 abolished the impact of the upregulation of miR-193a-3p on inflammation, apoptosis, and production of extracellular matrix in chondrocytes. In conclusion, NEAT1/miR-193a-3p/SOX5 axis regulates cartilage matrix degradation in human OA.

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.

Monotropein attenuates oxidative stress via Akt/mTOR-mediated autophagy in osteoblast cells

Oxidative stress is a crucial pathogenic factor in osteoporosis. Autophagy is a cellular self-digestion process that can selectively remove damaged organelles under oxidative stress, and thus presents a potential therapeutic target against osteoporosis. Monotropein is an iridoid glycoside which can increase osteoblastic bone formation and be applied for medicinal purpose in China. The aim of this work is to investigate whether autophagy participates the protection effects of monotropein in osteoblasts under oxidative stress and the possible mechanism of such involvement. Here, monotropein was capable of inhibiting the H₂O₂-induced reactive oxygen species generation in osteoblasts. Monotropein induced autophagy and protected osteoblasts from cytotoxic effects of H₂O₂, as assessed by viability assays, apoptosis and western blotting. Moreover, it significantly attenuated H₂O₂-evoked oxidative stress as measured by malondialdehyde, catalase, and superoxide dismutase levels. Importantly, monotropein reduced the phosphorylation of protein kinase B (Akt), mammalian target of rapamycin (mTOR) and its two downstream proteins (p70S6K and 4EBP1). The autophagy level increased in osteoblasts treated with monotropein as represented by an increased in both Beclin1 expression and the LC3-II/LC3-I ratio. However, the Akt activator (SC79) and mTOR activator (MHY1485) suppressed the autophagy level induced by monotropein in H₂O₂-treated cells. Consequently, the antioxidant effects of monotropein were mediated, at least in part, by enhancing autophagy through the Akt/mTOR pathway. These results suggested that monotropein might be a promising candidate for osteoporosis treatment.

Natural Products as Sources of Novel Drug Candidates for the Pharmacological Management of Osteoarthritis: A Narrative Review

Osteoarthritis is a chronic degenerative articular disorder. Formation of bone spurs, synovial inflammation, loss of cartilage, and underlying bone restructuring have been reported to be the main pathologic characteristics of osteoarthritis symptoms. The onset and progression of osteoarthritis are attributed to various inflammatory cytokines in joint tissues and fluids that are produced by chondrocytes and/or interact with chondrocytes, as well as to low-grade inflammation in intra-articular tissues. Disruption of the equilibrium between the synthesis and degradation of the cartilage of the joint is the major cause of osteoarthritis. Hence, developing a promising pharmacological tool to restore the equilibrium between the synthesis and degradation of osteoarthritic joint cartilage can be a useful strategy for effectively managing osteoarthritis. In this review, we provide an overview of the research results pertaining to the search for a novel candidate agent for osteoarthritis management via restoration of the equilibrium between cartilage synthesis and degradation. We especially focused on investigations of medicinal plants and natural products derived from them to shed light on the potential pharmacotherapy of osteoarthritis.

Artesunate alleviates interleukin‑1β‑induced inflammatory response and apoptosis by inhibiting the NF‑κB signaling pathway in chondrocyte‑like ATDC5 cells, and delays the progression of osteoarthritis in a mouse model

Osteoarthritis (OA) is a progressive and degenerative joint disorder that is highly prevalent worldwide and for which there is currently no effective medical therapy. Artesunate (ART), a natural compound used to treat malaria, possesses diverse biological properties, including the regulation of inflammation and apoptosis in various cells; however, its role in OA remains unclear. The aim of the present study was to investigate the effects of ART on interleukin (IL)‑1β‑induced chondrocyte‑like ATDC5 cells and in an OA mouse model. The results revealed that ART dose‑dependently relieved the inhibitory effect of IL‑1β on cell viability. Moreover, ART significantly reduced the overexpression of matrix metalloproteinase (MMP)‑3, MMP‑13, a disintegrin and metalloproteinase with thrombospondin motifs‑5 and cyclooxygenase‑2 at both the gene and protein levels in chondrocyte‑like ATDC5 cells stimulated by IL‑1β. Furthermore, ART decreased the expression of pro‑apoptotic Bax, cleaved caspase‑3 and cleaved caspase‑7 in a dose‑dependent manner, and increased the expression of the anti‑apoptotic factor Bcl‑2. These changes were mediated by the inhibitory effect of ART on the nuclear factor‑κB signaling pathway, defined as repression of the phosphorylation of IκBα and p65, and improved redistribution of p65. Additionally, ART blocked the advancement of the calcified cartilage zone and the loss of proteoglycan, and lowered histological scoring of OA in a mouse model. Taken together, these results indicate that ART may be of value as a therapeutic agent for OA.

Monoterpenes modulating cytokines - A review

Inflammatory response can be driven by cytokine production and is a pivotal target in the management of inflammatory diseases. Monoterpenes have shown that promising profile as agents which reduce the inflammatory process and also modulate the key chemical mediators of inflammation, such as pro and anti-inflammatory cytokines. The main interest focused on monoterpenes were to develop the analgesic and anti-inflammatory drugs. In this review, we summarized current knowledge on monoterpenes that produce anti-inflammatory effects by modulating the release of cytokines, as well as suggesting that which monoterpenoid molecules may be most effective in the treatment of inflammatory disease. Several different inflammatory markers were evaluated as a target of monoterpenes. The proinflammatory and anti-inflammatory cytokines were found TNF-α, IL-1β, IL-2, IL-5, IL-4, IL-6, IL-8, IL-10, IL-12 IL-13, IL-17A, IFNγ, TGF-β1 and IFN-γ. Our review found evidence that NF-κB and MAPK signaling are important pathways for the anti-inflammatory action of monoterpenes. We found 24 monoterpenes that modulate the production of cytokines, which appears to be the major pharmacological mechanism these compounds possess in relation to the attenuation of inflammatory response. Despite the compelling evidence supporting the anti-inflammatory effect of monoterpenes, further studies are necessary to fully explore their potential as anti-inflammatory compounds.

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.

Geniposide Suppresses Interleukin-1β-Induced Inflammation and Apoptosis in Rat Chondrocytes via the PI3K/Akt/NF-κB Signaling Pathway

Osteoarthritis (OA) is a chronic degenerative joint disease that is principally characterized by progressive joint dysfunction and cartilage degradation. Inflammation and apoptosis play critical roles in the progression of OA. Geniposide (GPO), one of the principal components of the fruit of Gardenia jasminoides Ellis, has been reported to have anti-inflammatory and other pharmacological effects. In this study, we performed in vitro experiments on rat chondrocytes to examine the therapeutic effects of GPO on OA and investigated its effects in vivo in a rat model of OA induced by medial meniscal tear (MMT). The results suggest that GPO can inhibit the expression of INOS, COX-2, and MMP-13 in vitro, and promote the expression of collagen II in rat chondrocytes stimulated with interleukin-1β (IL-1β). In addition, we also found that GPO can inhibit the expression of pro-apoptotic proteins such as Bax, Cyto-c, and C-caspase3 and increase the expression of the anti-apoptotic protein Bcl-2. These changes may be related to GPO-induced inhibition of the IL-1β-induced activation of the PI3K/Akt/NF-κB signaling pathway. In vivo, we also found that GPO can limit the development of OA in a rat model. Taken together, the above results indicate that GPO has potential therapeutic value for treating OA.

Morinda officinalis How. - A comprehensive review of traditional uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

The medicinal plant Morinda officinalisHow. (MO) and its root have long been used in traditional medicines in China and northeast Asia as tonics for nourishing the kidney, strengthening the bone and enhancing immunofunction in the treatment of impotence, osteoporosis, depression and inflammatory diseases such as rheumatoid arthritis and dermatitis.

AIM OF THE REVIEW

This review aims to sum up updated and comprehensive information about traditional usage, phytochemistry, pharmacology and toxicology of MO and provide insights into potential opportunities for future research and development of this plant.

METHODS

A bibliographic investigation was performed by analyzing the information available on MO in the internationally accepted scientific databases including Pubmed, Scopus and Web of Science, SciFinder, Google Scholar, Yahoo, Ph.D. and M.Sc. dissertations in Chinese. Information was also obtained from some local and foreign books on ethnobotany and ethnomedicines.

RESULTS

The literature supported the ethnomedicinal uses of MO as recorded in China for various purposes. The ethnomedical uses of MO have been recorded in many regions of China. More than 100 chemical compounds have been isolated from this plant, and the major constituents have been found to be polysaccharides, oligosaccharides, anthraquinones and iridoid glycosides. Crude extracts and pure compounds of this plant are used as effective agents in the treatment of depression, osteoporosis, fatigue, rheumatoid arthritis, and infertility due to their anti-depressant, anti-osteoporosis, pro-fertility, anti-radiation, anti-Alzheimer disease, anti-rheumatoid, anti-fatigue, anti-aging, cardiovascularprotective, anti-oxidation, immune-regulatory, and anti-inflammatory activities. Pharmacokinetic studies have demonstrated that the main components of MO including monotropein and deacetyl asperulosidic acid are distributed in various organs and tissues. The investigation on acute toxicity and genotoxicity indicated that MO is nontoxic. There have no reports on significant adverse effect at a normal dose in clinical application, but MO at dose of more than 1000mg/kg may cause irritability, insomnia and unpleasant sensations in individual cases.

CONCLUSION

MO has emerged as a good source of traditional medicines. Some uses of this plant in traditional medicines have been validated by pharmacological investigations. However, the molecular mechanism, structure-activity relationship, and potential synergistic and antagonistic effects of its multi-components such as polysaccharides, oligosaccharides, anthraquinones and iridoid glycosides need to be further elucidated, and the structural feature of polysaccharides also need to be further clarified. Sophisticated analytical technologies should be developed to comprehensively evaluate the quality of MO based on HPLC-fingerprint and content determination of the active constituents, knowing that these investigations will help further utilize this plant.

Isoliquiritigenin blunts osteoarthritis by inhibition of bone resorption and angiogenesis in subchondral bone

Isoliquiritigenin (ISL), a natural flavonoid extracted from licorice, has been demonstrated to exert attenuation of osteoclastogenesis and anti-angiogenesis activity in a wide variety of cells. Here, we first evaluated the effects of ISL on pathogenesis of osteoarthritis in a mouse model of OA. The data showed that ISL blunted progression of OA and lowered the Osteoarthritis Research Society International (OARSI)-Modified Making Score and protected the articular cartilage. The thickness of calcified cartilage zone was significantly decreased in ISL-treated ACLT mice compared with vehicle group. ISL increased expression level of lubricin and decreased collagen X (Col X), matrix metalloproteinase-13 (MMP-13). Moreover, ISL reduced aberrant active subchondral bone remodelling, including lowered trabecular pattern factor (Tb.pf) and increased bone volume/tissue volume (BV/TV, %) and thickness of subchondral bone plate (SBP) compared with vehicle-treated group. The results of immunostaining further revealed that ISL directly reduced RANKL-RANK-TRAF6 singling pathway induced osteoclastogenesis, prevented abnormal bone formation through indirect inhibition of TGF-β release. Additionally, ISL exerts anti-angiogenesis effects in subchondral bone through direct suppression of MMP-2. These results indicated that ISL attenuates progression of OA by inhibition of bone resorption and angiogenesis in subchondral bone, indicating that this may be a potential preventive therapy for OA.

Retracted Article: Salvianolic acid B inhibits inflammatory response and cell apoptosis via the PI3K/Akt signaling pathway in IL-1β-induced osteoarthritis chondrocytes

Osteoarthritis (OA) is the most common joint disease among late middle-aged or elderly people. The pathological process of OA mainly involves the degeneration of cartilage tissue and deficiency of joint function. Salvianolic acid B (Sal B) is the main active ingredient of Salvia miltiorrhiza Bge, which possesses anti-inflammatory, anti apoptotic and other pharmacological activities. In this study, primary chondrocytes were cultured to investigate the effects of Sal B on the inflammatory response and apoptosis of OA induced by IL-1β, and to explore the possible mechanism. First, we determined the cytotoxicity of Sal B; the results showed that the cell activity of chondrocytes was not influenced by Sal B when the concentration was below 150 μM. Moreover, Sal B (40 and 80 μM) suppressed the expression of iNOS in OA chondrocytes induced by IL-1β, and restrained the secretion of NO, IL-6, IL-17 and TNF-α in chondrocytes obviously. Sal B (40, 80 μM) significantly alleviated the inhibitory effect of cell activity stimulated by IL-1β and up-regulated the expression of Col II and reduced the expression of Col X. Besides, Sal B down-regulated the expression level of Bax and promoted the expression of Bcl-2, showed a significant effect on promoting proliferation and inhibiting cell apoptosis. In addition, we found that IL-1β significantly reduced the ratio of p-PI3K/PI3K, p-Akt/Akt induced the nuclear translocation of AKT and inhibited the activation of the PI3K/Akt signaling pathway. Finally, the PI3K inhibitor, LY-294002, was added in IL-1β-induced chondrocytes. The results suggest that Sal B ameliorates IL-1β induced inflammation and suppresses apoptosis in OA by activating the PI3K/Akt signaling pathway. Our study reveals the mechanism of Sal B acts on OA and may provide a basis for the treatment of OA with Sal B.

Osteoarthritis (OA) is the most common joint disease among late middle-aged or elderly people.

Monotropein promotes angiogenesis and inhibits oxidative stress-induced autophagy in endothelial progenitor cells to accelerate wound healing

Attenuating oxidative stress‐induced damage and promoting endothelial progenitor cell (EPC) differentiation are critical for ischaemic injuries. We suggested monotropein (Mtp), a bioactive constituent used in traditional Chinese medicine, can inhibit oxidative stress‐induced mitochondrial dysfunction and stimulate bone marrow‐derived EPC (BM‐EPC) differentiation. Results showed Mtp significantly elevated migration and tube formation of BM‐EPCs and prevented tert‐butyl hydroperoxide (TBHP)‐induced programmed cell death through apoptosis and autophagy by reducing intracellular reactive oxygen species release and restoring mitochondrial membrane potential, which may be mediated viamTOR/p70S6K/4EBP1 and AMPK phosphorylation. Moreover, Mtp accelerated wound healing in rats, as indicated by reduced healing times, decreased macrophage infiltration and increased blood vessel formation. In summary, Mtp promoted mobilization and differentiation of BM‐EPCs and protected against apoptosis and autophagy by suppressing the AMPK/mTOR pathway, improving wound healing in vivo. This study revealed that Mtp is a potential therapeutic for endothelial injury‐related wounds.

Isoliquiritigenin suppresses IL-1β induced apoptosis and inflammation in chondrocyte-like ATDC5 cells by inhibiting NF-κB and exerts chondroprotective effects on a mouse model of anterior cruciate ligament transection

Isoliquiritigenin (ISL), a natural flavonoid extracted from licorice, has been demonstrated to exert attenuation of the nuclear factor-κB (NF-κB) signaling pathway and anti-inflammatory activity in a wide variety of cells. In the present study, the authors first evaluated the effects of ISL on cartilage degeneration in interleukin-1β (IL-1β)-stimulated chondrocyte-like ATDC5 cells and in a mouse model of osteoarthritis (OA). The data of a cell counting kit-8 and flow cytometry assay indicated that ISL suppressed the inhibitory effect of IL-1β on cell viability. The mRNA and protein expression levels of cyclooxygenase-2 and matrix metalloproteinase-13 were significantly decreased, while the expression of collagen II was increased, as indicated by RT-qPCR and western blot analysis following the chondrocyte-like ATDC5 cells were co-intervened with IL-1β and ISL for 48 h. Also, ISL attenuated protein expressions level of pro-apoptotic Bax, cleaved-caspase-3 and cleaved-caspase-9 and promoted expression of anti-apoptotic Bcl-2. Moreover, ISL inhibited NF-κB p65 phosphorylation induced by IL-1β. In addition, ISL also increased improved the thickness of hyaline cartilage and the production of proteoglycans in the cartilage matrix in a mouse OA model. These results indicated that ISL exerted anti-inflammatory and anti-apoptotic effects on IL-1β-stimulated chondrocyte-like ATDC5 cells, which may be associated with the downregulation of the NF-κB signaling pathway. In this way, the data supported the conclusion that ISL may be a novel potential preventive agent suitable for use in OA therapy.

Yougui Pills Attenuate Cartilage Degeneration via Activation of TGF-β/Smad Signaling in Chondrocyte of Osteoarthritic Mouse Model

Yougui pills (YGPs) have been used for centuries in the treatment of Chinese patients with Kidney-Yang Deficiency Syndrome. Despite the fact that the efficiency of YGPs on treating osteoarthritis has been verified in clinic, the underlying mechanisms are not totally understood. The present study observes the therapeutic role of YGPs and mechanisms underlying its chondroprotective action in osteoarthritic cartilage. To evaluate the chondroprotective effects of YGPs, we examined the impact of orally administered YGPs in a model of destabilization of the medial meniscus (DMM). Male C57BL/6J mice were provided a daily treatment of YGPs and a DMM surgery was performed on the right knee. At 12 weeks post-surgery, the joints were harvested for tissue analyses, including histomorphometry, OARSI scoring, micro-CT and immunohistochemistry for COL-2, MMP-13 and pSMAD-2. We also performed the relative experiments mentioned above in mice with Tgfbr2 conditional knockout (TGF-βRII^Col2ER mice) in articular cartilage. To evaluate the safety of YGPs, hematology was determined in each group. Amelioration of cartilage degradation was observed in the YGPs group, with increases in cartilage area and thickness, proteoglycan matrix, and decreases in OARSI score at 12 weeks post surgery. In addition, reduced BV/TV and Tb. Th, and elevated Tb. Sp were observed in DMM-induced mice followed by YGPs treatment. Moreover, the preservation of cartilage correlated with reduced MMP-13, and elevated COL-2 and pSMAD-2 protein expressional levels were also revealed in DMM-induced mice treated with YGPs. Similarly, TGF-βRII^Col2ER mice exhibited significant OA-like phenotype. However, no significant difference in cartilage structure was observed in TGF-βRII^Col2ER mice after YGPs treatment. Interestingly, no obvious adverse effects were observed in mice from each group based on the hematologic analyses. These findings suggested that YGPs could inhibit cartilage degradation through enhancing TGF-β/Smad signaling activation, and be considered a good option for the treatment of osteoarthritis.

Insights into the Action Mechanisms of Traditional Chinese Medicine in Osteoarthritis

Osteoarthritis (OA) is a chronic degenerative joint disease characterized by articular cartilage destruction, synovial inflammation, and osteophyte formation. No effective treatments are available. The current pharmacological medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics, accompanied by possible adverse effects, might ameliorate OA symptoms. But they do not arrest the progression of OA. Traditional Chinese medicine (TCM) provides medical value by modification of disease and symptoms in OA. Valuable work on exploring TCM merits for OA patients has been investigated using modern technologies, although the complicated interacting network among the numerous components indicates the uncertainty of target specification. This review will provide an overview of the action mechanism of TCM in the last 5 years, discussing the TCM activities of anti-inflammation, antiapoptosis, antioxidation, anticatabolism, and proliferation in OA. TCM is a proposed medical option for OA treatment.

Increased Chondrogenic Potential of Mesenchymal Cells From Adipose Tissue Versus Bone Marrow-Derived Cells in Osteoarthritic In Vitro Models

Primarily, to compare the behavior of human mesenchymal stem cells (MSCs) derived from bone marrow (hBMSCs) and adipose tissue (hADSCs) in an osteoarthritic (OA) microenvironment; secondly, to investigate the reaction of these cell types in two alternative in vitro culture systems, obtained by using TNFα and/or IL1β as inflammation mediators, or by using synovial fluid harvested by OA patients (OSF) to simulate the complex inflamed knee microenvironment. 3D micromass cultures of hBMSCs or hADSCs were grown in chondrogenic medium (CTR), in the presence of TNFα and/or IL1β, or synovial fluid from OA patients. After 1 month of culture, the chondrogenic differentiation of micromasses was evaluated by gene expression, matrix composition, and organization. Both hMSCs types formed mature micromasses in CTR, but a better response of hADSCs to the inflammatory environment was documented by micromass area and Bern score evaluations. The addition of OSF elicited a milder reaction than with TNFα and/or IL1β by both cell types, probably due to the presence of both catabolic and protective factors. In particular, SOX9 and ACAN gene expression and GAG synthesis were more abundant in hADSCs than hBMSCs when cultured in OSF. The expression of MMP1 was increased for both hMSCs in inflammatory conditions, but in particular by hBMSCs. hADSCs showed an increased chondrogenic potential in inflammatory culture systems, suggesting a better response of hADSCs in the OA environment, thus underlining the importance of appropriate in vitro models to study MSCs and potential advantages of using these cells for future clinical applications. J. Cell. Physiol. 232: 1478-1488, 2017. © 2016 Wiley Periodicals, Inc.

Shikonin inhibits inflammation and chondrocyte apoptosis by regulation of the PI3K/Akt signaling pathway in a rat model of osteoarthritis

Shikonin has previously been shown to have antitumor, anti-inflammatory, antiviral and extensive pharmacological effects. The aim of the present study was to explore whether the protective effect of shikonin is mediated via the inhibition of inflammation and chondrocyte apoptosis, and to elucidate the potential molecular mechanisms in a rat model of osteoarthritis. A model of osteoarthritis was established in healthy male Sprague-Dawley rats and 10 mg/kg/day shikonin was administered intraperitoneally for 4 days. It was found that shikonin treatment significantly inhibited inflammatory reactions in the rats with osteoarthritis. Osteoarthritis was found to significantly increase interleukin (IL)-1β, tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) levels compared with those in the sham group. However, shikonin treatment significantly inhibited the increases in IL-1β, TNF-α and iNOS levels in the rats with osteoarthritis. Furthermore, caspase-3 activity and cyclooxygenase (COX)-2 protein expression were significantly increased and phosphorylated Akt protein expression was greatly suppressed in rats with osteoarthritis when compared with the sham group. Shikonin administration attenuated the changes in caspase-3 activity and COX-2 expression and Akt phosphorylation in rats with osteoarthritis. These results indicate that shikonin inhibits inflammation and chondrocyte apoptosis by regulating the phosphoinositide 3-kinase/Akt signaling pathway in a rat model of osteoarthritis.

Anti-Diabetic Potential of Noni: The Yin and the Yang

Escalating trends of chronic diseases such as type-2 diabetes (T2D) have sparked a renewed interest in complementary and alternative medicine, including herbal products. Morinda citrifolia (noni) has been used for centuries by Pacific Islanders to treat various ailments. Commercial noni fruit juice has been marketed as a dietary supplement since 1996. In 2003, the European Commission approved Tahitian noni juice as a novel food by the Health and Consumer Protection Directorate General. Among noni's several health benefits, others and we have demonstrated the anti-diabetic effects of fermented noni fruit juice in animal models. Unfortunately, noni's exciting journey from Polynesian medicine to the research bench does not reach its final destination of successful clinical outcomes when translated into commercial products. Noni products are perceived to be safe due to their "natural" origin. However, inadequate evidence regarding bioactive compounds, molecular targets, mechanism of action, pharmacokinetics, long-term safety, effective dosages, and/or unanticipated side effects are major roadblocks to successful translation "from bench side to bedside". In this review we summarize the anti-diabetic potential of noni, differences between traditional and modern use of noni, along with beneficial clinical studies of noni products and challenges in clinical translation of noni's health benefits.