Chondroprotective Effects of Ginsenoside Rg1 in Human Osteoarthritis Chondrocytes and a Rat Model of Anterior Cruciate Ligament Transection

Therapeutic Potential of Ginsenosides on Bone Metabolism: A Review of Osteoporosis, Periodontal Disease and Osteoarthritis

Ginsenosides, bioactive compounds from the genus Panax, have potential therapeutic effects on diverse ailments, including diabetes. Emerging evidence suggests their involvement in bone metabolism. The present review summarizes the current understanding of the effects of ginsenosides on osteoporosis, periodontal disease, and osteoarthritis. Their mechanisms of action include effects on osteoblasts, osteoclasts, periodontal ligament fibroblasts (PDLFs), and chondrocytes, which are pivotal in maintaining bone, periodontal tissue, and cartilage homeostasis. Ginsenosides may exert their beneficial effects by enhancing PDLF and osteoblast activity, suppressing osteoclast function, augmenting chondrocyte synthesis in the cartilage matrix, and mitigating connective tissue degradation. Moreover, they possess antioxidant, anti-inflammatory, antimicrobial, and anti-pyroptotic properties. Their efficacy in increasing bone density, ameliorating periodontitis, and alleviating osteoarthritis symptoms has been demonstrated in preclinical studies using animal models. In terms of their mechanism of action, ginsenosides modulate cellular differentiation, activity, and key signaling pathway molecules, such as mitogen-activated protein kinases (MAPKs), while also regulating various mediators. Furthermore, the symptomatic relief observed in animal models lends further credence to their therapeutic utility. However, to translate these preclinical findings into clinical practice, rigorous animal and clinical investigations are imperative to ascertain the safety, efficacy, and optimal dosing regimens in human subjects.

Medical treatment of osteoarthritis: botanical pharmacologic aspect

Osteoarthritis (OA) is the most common form of arthritis, and its prevalence is expected to further increase as our society ages. Despite many approaches to cure OA, no drugs are currently proven to modulate the progression of OA. Nowadays, new OA treatment options are holistically developed and one of the approaches of treatment option is botanical drugs. Some botanical drugs for OA have shown both therapeutic effect comparable to refined drugs in small studies and fewer side effects. Hence, there are various health functional foods which are known to relieve symptoms of OA. However, since there are many botanical products, clinicians are not familiar to the efficacy of each botanical product, making it challenging to use them appropriately in clinical practice. Here, we summarize the botanical products available for treating OA, including prescription botanical drugs and health functional foods available in Korea. Further studies and the purification of effective molecules from botanical products will be necessary in future.

Ginsenoside Rg1/ADSCs supplemented with hyaluronic acid as the matrix improves rabbit temporomandibular joint osteoarthrosis

OBJECTIVE

To investigate whether and how ginsenoside Rg1/ADSCs supplemented with hyaluronic acid as the matrix can improve rabbit temporomandibular joint osteoarthrosis.

METHOD

Isolate and culture adipose stem cells, measure the activity of differentiated chondrocytes by MTT assay and expression of type II collagen in these cells by immunohistochemistry, in order to evaluate the effect of ginsenoside Rg1 on adipose stem cell proliferation and differentiation into chondrocytes.32 New Zealand white rabbits were randomly divided into four groups: blank group, model group, control group and experimental group, 8 in each group. Osteoarthritis model was established by intra-articular injection of papain. Two weeks after successful model building, medication was given for the rabbits in control group and experimental group. 0.6 mL ginsenoside Rg1/ ADSCs suspension was injected into superior joint space for the rabbits in control group, once a week; 0.6 mL ginsenoside Rg1/ ADSCs complex was injected for the rabbits in experimental group, once a week.

RESULTS

Ginsenoside Rg1 can promote ADSCs-derived chondrocytes' activity and expression of type II collagen. Scanning electron microscopy histology images showed cartilage lesions of the experimental group was significantly improved in comparison with control group.

CONCLUSION

Ginsenoside Rg1 can promote ADSCs differentiate into chondrocytes, and Ginsenoside Rg1/ADSCs supplemented with hyaluronic acid as the matrix can significantly improve rabbit temporomandibular joint osteoarthrosis.

Advancing Kir4.2 Channel Ligand Identification through Collision-Induced Affinity Selection Mass Spectrometry

The inwardly rectifying potassium Kir4.2 channel plays a crucial role in regulating membrane potentials and maintaining potassium homeostasis. Kir4.2 has been implicated in various physiological processes, including insulin secretion, gastric acid regulation, and the pathogenesis of central nervous system diseases. Despite its significance, the number of identified ligands for Kir4.2 remains limited. In this study, we established a method to directly observe ligands avoiding a requirement to observe the high-mass ligand-membrane protein-detergent complexes. This method used collision-induced affinity selection mass spectrometry (CIAS-MS) to identify ligands dissociated from the Kir4.2 channel-detergent complex. The CIAS-MS approach integrated all stages of affinity selection within the mass spectrometer, offering advantages in terms of time efficiency and cost-effectiveness. Additionally, we explored the effect of collisional voltage ramps on the dissociation behavior of the ligand and the ligand at different concentrations, demonstrating dose dependency.

Natural products in osteoarthritis treatment: bridging basic research to clinical applications

Osteoarthritis (OA) is the most prevalent degenerative musculoskeletal disease, severely impacting the function of patients and potentially leading to disability, especially among the elderly population. Natural products (NPs), obtained from components or metabolites of plants, animals, microorganisms etc., have gained significant attention as important conservative treatments for various diseases. Recently, NPs have been well studied in preclinical and clinical researches, showing promising potential in the treatment of OA. In this review, we summed up the main signaling pathways affected by NPs in OA treatment, including NF-κB, MAPKs, PI3K/AKT, SIRT1, and other pathways, which are related to inflammation, anabolism and catabolism, and cell death. In addition, we described the therapeutic effects of NPs in different OA animal models and the current clinical studies in OA patients. At last, we discussed the potential research directions including in-depth analysis of the mechanisms and new application strategies of NPs for the OA treatment, so as to promote the basic research and clinical transformation in the future. We hope that this review may allow us to get a better understanding about the potential bioeffects and mechanisms of NPs in OA therapy, and ultimately improve the effectiveness of NPs-based clinical conservative treatment for OA patients.

Protective effects of ginseng and ginsenosides in the development of osteoarthritis (Review)

Osteoarthritis (OA) is a chronic inflammatory joint disease. Traditional chinese medicine provides a resource for drug screening for OA treatment. Ginseng and the associated bioactive compound, ginsenosides, may reduce inflammation, which is considered a risk factor for the development of OA. Specifically, ginsenosides may exhibit anti-inflammatory and anti-oxidative stress activities, and inhibit extracellular matrix degradation by suppressing the NF-κB and MAPK signaling pathways. Notably, specific ginsenosides, such as compound K and Rk1, may physically interact with IκB kinase and inhibit the associated phosphorylation. Thus, ginsenosides exhibit potential as therapeutic candidates in the management of OA. However, the low water solubility limits the clinical applications of ginsenosides. Numerous effective strategies have been explored to improve bioavailability; however, further investigations are still required.

Ginsenoside compound K alleviates osteoarthritis by inhibiting NLRP3‑mediated pyroptosis

Ginsenoside compound K (GCK) has been previously reported to be a potent antiarthritic and bone-protective agent. Therefore, the present study aimed to explore the potential effects of GCK on osteoarthritis and its regulatory effects on the pyroptosis of chondrocytes. Primary mouse chondrocytes (PMCs) were used for in vitro analysis. ELISA assays revealed that compared with the untreated cells, TNF-α induced a significant increase in IL-6, MMP13, A disintegrin and metalloproteinase with thrombospondin motifs 5 and MMP3 expression but induced a significant decrease in aggrecan and collagen II expression. By contrast, GCK reversed the aforementioned alterations in a dose-dependent manner. Experimental osteoarthritis was subsequently induced in mice through transection of the medial meniscotibial ligament and medial collateral ligament in the right knee [destabilization of the medial meniscus (DMM) mice]. GCK was found to reduce cartilage degradation in vivo in DMM mice, which was assessed using the Osteoarthritis Research Society International (OARSI) score, collagen II and MMP13 expression. Cartilage degradation is associated with higher OARSI score, decreased collagen II and increased MMP13 expression. In PMCs, TNF-α treatment stimulated an increase in the expression of NLR family pyrin domain containing 3 (NLRP3), Gasdermin D-N terminal (GSDMD-NT), cleaved caspase-1 and mature IL-1β, markers that indicate the occurrence of pyroptosis. However, GCK treatment suppressed the increase of the aforementioned proteins in a dose-dependent manner. Immunohistochemistry staining of the knee joint tissue sections from the DMM mice confirmed that GCK attenuated the NLRP3 and GSDMD-NT expression that was induced by DMM surgery. In conclusion, the present study revealed that GCK can reduce cartilage degradation in an osteoarthritis model by inhibiting the NLRP3-inflammasome activation and subsequent pyroptosis.

Ginsenoside Rg1 attenuation of neurogenesis disorder and neuronal apoptosis in the rat hippocampus after spinal cord injury may involve brain-derived neurotrophic factor/extracellular signal-regulated kinase signaling

OBJECTIVE

We previously demonstrated that spinal cord injury (SCI) induced hippocampus injury and depression in rodents. Ginsenoside Rg1 effectively prevents neurodegenerative disorders. Here, we investigated the effects of ginsenoside Rg1 on the hippocampus after SCI.

METHODS

We used a rat compression SCI model. Western blotting and morphologic assays were used to investigate the protective effects of ginsenoside Rg1 in the hippocampus.

RESULTS

Brain-derived neurotrophic factor/extracellular signal-regulated kinases (BDNF/ERK) signaling was altered in the hippocampus at 5 weeks after SCI. SCI attenuated neurogenesis and enhanced the expression of cleaved caspase-3 in the hippocampus; however, ginsenoside Rg1 attenuated cleaved caspase-3 expression and improved neurogenesis and BDNF/ERK signaling in the rat hippocampus. The results suggest that SCI affects BDNF/ERK signaling, and ginsenoside Rg1 can attenuate hippocampal damage after SCI.

CONCLUSION

We speculate that the protective effects of ginsenoside Rg1 in hippocampal pathophysiology after SCI may involve BDNF/ERK signaling. Ginsenoside Rg1 shows promise as a therapeutic pharmaceutical product when seeking to counter SCI-induced hippocampal damage.

Ginsenoside Rg1 regulates thiram-induced chondrocytes' apoptosis and angiogenesis in broiler chickens

Tibial dyschondroplasia (TD) is a developmental cartilaginous disease due to thiram toxicity. The abnormity of chondrocytes and insufficient angiogenesis within the growth plate are the major factors leading to the occurrence of TD in most cases. In the current study, we evaluated the beneficial effects of ginsenoside (Rg1) against thiram-induced TD for knowing the possible underlying mechanisms in broiler chickens through in vivo and in vitro assessment. Arbor acres broilers (1-day-old, n = 120) were randomly divided for the in vivo evaluation. The control broilers were fed under normal conditions during the whole experiment cycle (18 days). The TD broilers were fed with 50 mg/kg thiram, while the treatment group was given 40 mg/kg of Rg1. According to our findings, thiram caused a decrease in production performance and tibia parameters (p < 0.05), which were significantly reversed by Rg1 administration. In addition, the results from the histological evaluation showed that the proliferative zone had a smaller number of blood vessels, surrounded by inviable chondrocytes, proving apoptosis during the occurrence of TD, while Rg1 treatment significantly increased blood vessels and decreased apoptotic cells. Furthermore, it was found that Rg1 effectively ameliorated the angiogenesis by regulation of HIF-1α/VEGFA/VEGFR2 signaling pathway and the chondrocytes' apoptosis via the mitochondrial pathway. Hence, these findings suggest that Rg1 might be a perfect choice in the prevention and treatment of TD via regulating chondrocytes apoptosis and angiogenesis. Also, it might be a potential therapeutic drug for humans to overcome different bone disorders, involving chondrocytes.

Ginsenoside Rb1 from Panax ginseng attenuates monoiodoacetate-induced osteoarthritis by inhibiting miR-21-5p/FGF18-mediated inflammation

Ginsenoside Rb1 (Rb1) is a major active compound in Panax ginseng and has shown considerable anti-inflammation effects. Osteoarthritis (OA) is one of the major degenerative disorders affecting the knee. MiR-21-5p is a potential therapeutic target for OA treatment. This study explored the anti-OA effects of Rb1 by focusing on its interaction with the miR-21-5p/FGF18 axis. OA was induced in rats using monoiodoacetate (MIA) and managed with Rb1. Then, changes in the histological structure and miR-21-5p-mediated signaling pathway were measured in joint tissues. The role of miR-21-5p/FGF18 in the anti-OA effects of Rb1 was confirmed by inducing its levels in rats and chondrocytes. Rb1 improved the histological structure and suppressed the production of cytokines in joint tissues. At the molecular level, Rb1 down-regulated miR-12-5p levels and up-regulated FGF18 levels. In chondrocytes, Rb1 increased cell viability, suppressed inflammation, down-regulated miR-21-5p levels, and up-regulated FGF18 levels. The restored level of miR-21-5p compromised the anti-OA effects of Rb1. In a nutshell, our study reported that the anti-OA effects of Rb1 relied on the inhibited expression of miR-21-5p. PRACTICAL APPLICATIONS: Ginsenoside Rb1 (Rb1) is a major active compound in Panax ginseng and has shown considerable anti-osteoarthritis (OA) effects. The current study not only relates the anti-OA function of ginsenoside Rb1 with microRNA but also provides valuable information for exploring novel targets for the development the anti-OA strategies.

Oral Administration of Clostridium butyricum GKB7 Ameliorates Signs of Osteoarthritis in Rats

Osteoarthritis (OA) is a degenerative and painful inflammatory joint disease affecting the cartilage, bone, and synovial membranes, without any effective treatment that targets the underlying mechanisms of OA. Our study evaluated the therapeutic effects of a live probiotic strain, Clostridium butyricum GKB7, administered for 6 weeks to rats with knee OA (KOA) induced by anterior cruciate ligament transection (ACLT) of the right knee. All rats underwent weekly weight-bearing behavioral testing and body weight measurements. At 6 weeks, all rats were sacrificed, and the right hind knees were collected for micro-computed tomography imaging and histopathological and immunohistochemical analyses. Compared with rats in the ACLT-only group, ACLT rats administered the probiotic exhibited dramatic improvements in pain-related behavior from postoperative week 2, had significantly less osseous and cartilaginous damage at week 6, and significantly lower levels of the inflammatory markers interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) in cartilage and synovium sections. C. butyricum GKB7 appeared to slow or even reverse OA progression and is worth investigating as a novel therapeutic for OA.

Anti-fatigue effect from Ginseng Radix et Rhizoma: a suggestive and promising treatment for long COVID

Two years after the coronavirus disease 2019 (COVID-19) outbreak, an increasing number of patients continue to suffer from long COVID (LC), persistent symptoms, and/or delayed or long-term complications beyond the initial 4 weeks from the onset of symptoms. Constant fatigue is one of the most common LC symptoms, leading to severely reduced quality of life among patients. Ginseng Radix et Rhizoma-known as the King of Herbs in traditional Chinese medicine-has shown clinical anti-fatigue effects. In this review, we summarize the underlying anti-fatigue mechanisms of Ginseng Radix et Rhizoma extracts and their bioactive compounds, with a special focus on anti-viral, immune remodeling, endocrine system regulation, and metabolism, suggesting that Ginseng Radix et Rhizoma is a potentially promising treatment for LC, especially in regard to targeting fatigue.

The Traditional Chinese Medicine "Hu-Qian-Wan" Attenuates Osteoarthritis-Induced Signs and Symptoms in an Experimental Rat Model of Knee Osteoarthritis

BACKGROUND

Knee osteoarthritis (KOA) is a chronic, low-grade inflammatory disease that affects knee joints and causes functional disability in the elderly. KOA is typically treated with oral NSAIDs, which are commonly associated with gastrointestinal side effects or cardiovascular complications. Traditional Chinese medicine (TCM) is widely used by patients with KOA in Taiwan; the Hu-Qian-Wan (HQW) formula is typically prescribed. We investigated the therapeutic role of a modified version of the HQW decoction in Sprague-Dawley rats with KOA induced by anterior cruciate ligament transection (ACLT) of the right knee.

MATERIALS AND METHODS

Thirty rats were randomly assigned to five groups (six animals each): arthrotomy alone (sham surgery, controls), ACLT only, ACLT + low-dose (1,000 mg/kg) HQW, ACLT + high-dose (3,000 mg/kg) HQW, and ACLT + celecoxib (30 mg/kg). All study groups underwent weight-bearing behavioral testing, micro-computed tomography (CT), and histological examinations of the knee joint cartilage, as well as immunohistochemical analyses of levels of interleukin (IL) 1β and tumor necrosis factor (TNF) α expression in articular cartilage.

RESULTS

At 6 weeks, compared with ACLT group only, ACLT rats administered high-dose HQW or celecoxib exhibited the fewest weight-bearing deficits, the greatest improvements from baseline in articular cartilage architecture, and the lowest amounts of TNF-α and IL-1β staining in cartilage and synovial sections (all values were significant compared with the ACLT-only group). The only values that were significantly increased by ACLT + low-dose HQW compared with ACLT alone were bone mineral density and trabecular numbers.

CONCLUSION

Our findings suggest that high-dose HQW improves weight-bearing asymmetry, decreases bone loss, and reduces levels of TNF-α and IL-1β in the affected joint in ACLT-induced KOA rats. More evidence is needed to support our findings.

American Ginseng Attenuates Eccentric Exercise-Induced Muscle Damage via the Modulation of Lipid Peroxidation and Inflammatory Adaptation in Males

Exercise-induced muscle damage (EIMD) is characterized by a reduction in functional performance, disruption of muscle structure, production of reactive oxygen species, and inflammatory reactions. Ginseng, along with its major bioactive component ginsenosides, has been widely employed in traditional Chinese medicine. The protective potential of American ginseng (AG) for eccentric EIMD remains unclear. Twelve physically active males (age: 22.4 ± 1.7 years; height: 175.1 ± 5.7 cm; weight: 70.8 ± 8.0 kg; peak oxygen consumption [V˙O2peak] 54.1 ± 4.3 mL/kg/min) were administrated by AG extract (1.6 g/day) or placebo (P) for 28 days and subsequently challenged by downhill (DH) running (−10% gradient and 60% V˙O2peak). The levels of circulating 8-iso-prostaglandin F 2α (PGF2α), creatine kinase (CK), interleukin (IL)-1β, IL-4, IL-10, and TNF-α, and the graphic pain rating scale (GPRS) were measured before and after supplementation and DH running. The results showed that the increases in plasma CK activity induced by DH running were eliminated by AG supplementation at 48 and 72 h after DH running. The level of plasma 8-iso-PGF2α was attenuated by AG supplementation immediately (p = 0.01 and r = 0.53), 2 h (p = 0.01 and r = 0.53) and 24 h (p = 0.028 and r = 0.45) after DH running compared with that by P supplementation. Moreover, our results showed an attenuation in the plasma IL-4 levels between AG and P supplementation before (p = 0.011 and r = 0.52) and 72 h (p = 0.028 and r = 0.45) following DH running. Our findings suggest that short-term supplementation with AG alleviates eccentric EIMD by decreasing lipid peroxidation and promoting inflammatory adaptation.

Pharmacological activities of ginsenoside Rg5 (Review)

Ginseng, a perennial plant belonging to genus Panax, has been widely used in traditional herbal medicine in East Asia and North America. Ginsenosides are the most important pharmacological component of ginseng. Variabilities in attached positions, inner and outer residues and types of sugar moieties may be associated with the specific pharmacological activities of each ginsenoside. Ginsenoside Rg5 (Rg5) is a minor ginsenoside synthesized during ginseng steaming treatment that exhibits superior pharmaceutical activity compared with major ginsenosides. With high safety and various biological functions, Rg5 may act as a potential therapeutic candidate for diverse diseases. To date, there have been no systematic studies on the activity of Rg5. Therefore, in this review, all available literature was reviewed and discussed to facilitate further research on Rg5.

Ginsenoside Rg1 Prevents PTSD-Like Behaviors in Mice Through Promoting Synaptic Proteins, Reducing Kir4.1 and TNF-α in the Hippocampus

Ginsenoside Rg1 is efficient to prevent or treat mental disorders. However, the mechanisms underlying the effects of ginsenoside Rg1 on post-traumatic stress disorder (PTSD) are still not known. In this study, single-prolonged stress (SPS) regime, as well as injection of lipopolysaccharide (LPS), was used to produce PTSD-like behaviors in C57 mice, and the effects of ginsenoside Rg1 (10, 20, 40 mg/kg/d, ip, for 14 days) on PTSD-like behaviors were evaluated. Our results showed that ginsenoside Rg1 promoted fear extinction and prevented depression-like behaviors in both LPS and SPS models. Importantly, ginsenoside Rg1 alleviated LPS- or SPS-stimulated expression of pro-inflammatory cytokines (IL-1β and TNF-α), activation of astrocytes and microglia, and reduction of hippocampal synaptic proteins (PSD95, Arc, and GluA1). Ginsenoside Rg1 also reduced the increase of hippocampal Kir4.1 and GluN2A induced by PTSD regime. Importantly, reducing hippocampal astroglial Kir4.1 expression promoted fear extinction and improved depression-like behaviors in LPS-treated mice. Additionally, intracerebroventricular injection of TNF-α caused an impairment of fear extinction and promoted Kir4.1 expression in the hippocampus. Together, our study reveals novel protective effects of ginsenoside Rg1 against PTSD-like behaviors in mice, likely via promoting synaptic proteins, reducing Kir4.1 and TNF-α in the hippocampus.

Anti-Metastatic and Anti-Inflammatory Effects of Matrix Metalloproteinase Inhibition by Ginsenosides

Matrix metalloproteinases (MMPs) are proteolytic enzymes which cleave extracellular matrix (ECM) and other substrates. They are deeply involved in both cancer metastasis and human chronic inflammatory diseases such as osteoarthritis and Crohn’s disease. Regulation of MMPs is closely associated with signaling molecules, especially mitogen-activated protein kinases (MAPKs), including three representative kinases, extracellular signal regulated kinases (ERK), p38 and c-Jun N-terminal kinases (JNK). Ginseng (Panax sp.) is a plant which has been traditionally used for medicinal applications. Ginsenosides are major metabolites which have potentials to treat various human diseases. In this review, the pharmacological effects of ginsenosides have been rigorously investigated; these include anti-metastatic and anti-inflammatory activities of ginsenosides associated with suppression of MMPs via regulation of various signaling pathways. This will highlight the importance of MMPs as therapeutic targets for anti-metastatic and anti-inflammatory drug development based on ginsenosides.

Emerging Natural-Product-Based Treatments for the Management of Osteoarthritis

Osteoarthritis (OA) is a complex degenerative disease in which joint homeostasis is disrupted, leading to synovial inflammation, cartilage degradation, subchondral bone remodeling, and resulting in pain and joint disability. Yet, the development of new treatment strategies to restore the equilibrium of the osteoarthritic joint remains a challenge. Numerous studies have revealed that dietary components and/or natural products have anti-inflammatory, antioxidant, anti-bone-resorption, and anabolic potential and have received much attention toward the development of new therapeutic strategies for OA treatment. In the present review, we provide an overview of current and emerging natural-product-based research treatments for OA management by drawing attention to experimental, pre-clinical, and clinical models. Herein, we review current and emerging natural-product-based research treatments for OA management.

Ginsenoside Rb1/TGF-β1 loaded biodegradable silk fibroin-gelatin porous scaffolds for inflammation inhibition and cartilage regeneration

Creating a microenvironment with low inflammation and favorable for the chondrogenic differentiation of endogenous stem cells plays an essential role in cartilage repairing. In the present study, we design a novel ginsenoside Rb1/TGF-β1 loaded silk fibroin-gelatin porous scaffold (GSTR) with the function of attenuating inflammation and promoting chondrogenesis. The scaffold has porous microstructure, proper mechanical strength, degradation rate and sustained release of Rb1 and TGF-β1. Rat bone marrow-derived mesenchymal stem cells (rBMSCs) seeded into GSTR scaffolds are homogeneously distributed and display a higher proliferation rate than non-loaded scaffolds (GS). GSTR scaffolds promote the chondrogenic differentiation of rBMSCs and suppress the expression of inflammation genes. Under the stimulation of IL-1β, the inflammation level of the chondrocytes seeded in GSTR scaffolds is also significantly down-regulated. Moreover, GSTR scaffolds implanted into the osteochondral defects in rats effectively promote the regeneration of hyaline cartilage 12 weeks after surgery when compared with other groups. It is demonstrated that this scaffold loaded with Rb1 and TGF-β1 can synergistically create a microenvironment favorable for cartilage regeneration by promoting the chondrogenesis and suppressing the inflammation levels in vivo. These results prove it has a great potential to develop this Rb1/TGF-β1 releasing scaffold into a novel and promising therapeutic for cartilage repair.

Antiobesity Effects of Ginsenoside Rg1 on 3T3-L1 Preadipocytes and High Fat Diet-Induced Obese Mice Mediated by AMPK

Ginsenosides Rg1 is one of the major pharmacologically active saponins in ginseng, which as an antioxidant reduces oxidative damage in the liver and can also be used to prevent cardiovascular diseases and diabetes. However, there is no research targeting the effect of lipid metabolism in high-fat diet (HFD)-induced mice. In this study, we evaluated the anti-obesity effects of Rg1 in 3T3-L1 adipocyte cells and HFD-induced obese C57BL/6J mice. Administration of Rg1 to HFD-induced obese mice significantly decreased body weight, total cholesterol, and total triglyceride levels. In addition to effects in 3T3-L1 cells, Rg1 reduced the accumulation of lipid droplets in a dose-dependent manner. Furthermore, Rg1 exhibits an anti-adipogenic effect via regulation of the expression of the transcriptional factors and lipid metabolism-related genes in vivo and in vitro. We observed that Rg1 administration significantly increased the phosphorylation level of AMP-activated protein kinase (AMPK) in both epididymal white adipose tissue and 3T3-L1 cells. These results indicated that Rg1 works both in an anti-adipogenic and anti-obesity manner through inducing AMPK activation, inhibiting lipogenesis, and decreasing intracellular lipid content, adipocyte size, and adipose weight.

Characterization of a novel thermostable and xylose-tolerant GH 39 β-xylosidase from Dictyoglomus thermophilum

Background

β-D-xylosidase is a vital exoglycosidase with the ability to hydrolyze xylooligosaccharides to xylose and to biotransform some saponins by cleaving outer β-xylose. β-D-xylosidase is widely used as one of the xylanolytic enzymes in a diverse range of applications, such as fuel, food and the pharmaceutical industry; therefore, more and more studies have focused on the thermostable and xylose-tolerant β-D-xylosidases.

Results

A thermostable β-xylosidase gene (xln-DT) of 1509 bp was cloned from Dictyoglomus thermophilum and expressed in E.coli BL21. According to the amino acid and phylogeny analyses, the β-xylosidase Xln-DT is a novel β-xylosidase of the GH family 39. The recombinant β-xylosidase was purified, showing unique bands on SDS-PAGE, and had a protein molecular weight of 58.7 kDa. The β-xylosidase Xln-DT showed an optimal activity at pH 6.0 and 75 °C, with p-nitrophenyl-β-D-xylopyranoside (pNPX) as a substrate. Xln-DT displayed stability over a pH range of 4.0-7.5 for 24 h and displayed thermotolerance below 85 °C. The values of the kinetic parameters K_m and V_max for pNPX were 1.66 mM and 78.46 U/mg, respectively. In particular, Xln-DT displayed high tolerance to xylose, with 60% activity in the presence of 3 M xylose. Xln-DT showed significant effects on the hydrolyzation of xylobiose. After 3 h, all the xylobiose tested was degraded into xylose. Moreover, β-xylosidase Xln-DT had a high selectivity for cleaving the outer xylose moieties of natural saponins, such as notoginsenoside R1 and astragaloside IV, which produced the ginsenoside Rg1 with stronger anti-fatigue activity and produced cycloastragenol with stronger anti-aging activity, respectively.

Conclusion

This study provides a novel GH 39 β-xylosidase displaying extraordinary properties of highly catalytic activity at temperatures above 75 °C, remarkable hydrolyzing activity of xylooligosaccharides and rare saponins producing ability in the pharmaceutical and commercial industries.

Electronic supplementary material

The online version of this article (10.1186/s12896-018-0440-3) contains supplementary material, which is available to authorized users.

Nutrients, Infectious and Inflammatory Diseases

A balanced diet with sufficient essential nutritional elements is critical for maintaining a healthy body.[...].