Amelioration of insulin resistance by Rk1 + Rg5 complex under endoplasmic reticulum stress conditions

Recent trends in ginseng research

Ginseng, the dried root of Panax ginseng, contains ginsenosides and has long been used in Korea, China, and Japan to treat various symptoms. Many studies on the utility of ginseng have been conducted and in this paper we investigate recent trends in ginseng research. P. ginseng studies were collected from scientific databases (PubMed, Web of Science, and SciFindern) using the keywords "Panax ginseng C.A. Meyer", "ginsenosides", "genetic diversity", "biosynthesis", "cultivation", and "pharmacology". We identified 1208 studies up to and including September 2023: 549 studies on pharmacology, 262 studies on chemical components, 131 studies on molecular biology, 58 studies on cultivation, 71 studies on tissue culture, 28 studies on clinical trials, 123 reviews, and 49 studies in other fields. Many researchers focused on the characteristic ginseng component ginsenoside to elucidate the mechanism of ginseng's pharmacological action, the relationship between component patterns and cultivation areas and conditions, and gene expression.

Ginsenoside Rk1 Ameliorates ER Stress-Induced Apoptosis through Directly Activating IGF-1R in Mouse Pancreatic [Formula: see text]-Cells and Diabetic Pancreas

Hyperglycemia induces chronic stresses, such as oxidative stress and endoplasmic reticulum (ER) stress, which can result in [Formula: see text]-cell dysfunction and development of Type 2 Diabetes Mellitus (T2DM). Ginsenoside Rk1 is a minor ginsenoside isolated from Ginseng. It has been shown to exert anti-cancer, anti-inflammatory, anti-oxidant, and neuroprotective effects; however, its effects on pancreatic cells in T2DM have never been studied. This study aims to examine the novel effects of Ginsenoside Rk1 on ER stress-induced apoptosis in a pancreatic [Formula: see text]-cell line MIN6 and HFD-induced diabetic pancreas, and their underlying mechanisms. We demonstrated that Ginsenoside Rk1 alleviated ER stress-induced apoptosis in MIN6 cells, which was accomplished by directly targeting and activating insulin-like growth factor 1 receptor (IGF-1R), thus activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/Bcl-2-associated agonist of cell death (Bad)-B-cell lymphoma-2 (Bcl-2) pathway. This pathway was also confirmed in an HFD-induced diabetic pancreas. Meanwhile, the use of the IGF-1R inhibitor PQ401 abolished this anti-apoptotic effect, confirming the role of IGF-1R in mediating anti-apoptosis effects exerted by Ginsenoside Rk1. Besides, Ginsenoside Rk1 reduced pancreas weights and increased pancreatic insulin contents, suggesting that it could protect the pancreas from HFD-induced diabetes. Taken together, our study provided novel protective effects of Ginsenoside Rk1 on ER stress-induced [Formula: see text]-cell apoptosis and HFD-induced diabetic pancreases, as well as its direct target with IGF-1R, indicating that Ginsenoside Rk1 could be a potential drug for the treatment of T2DM.

Ginsenoside Rg5 as an anticancer drug: a comprehensive review on mechanisms, structure-activity relationship, and prospects for clinical advancement

Cancer remains one of the leading causes of death in the world. Despite the considerable success of conventional treatment strategies, the incidence and mortality rates are still high, making developing new effective anticancer therapies an urgent priority. Ginsenoside Rg5 (Rg5) is a minor ginsenoside constituent obtained exclusively from ginseng species and is known for its broad spectrum of pharmacological activities. This article aimed to comprehensively review the anticancer properties of Rg5, focusing on action mechanisms, structure-activity relationship (SAR), and pharmacokinetics attributes. The in vitro and in vivo activities of Rg5 have been proven against several cancer types, such as breast, liver, lung, bone, and gastrointestinal (GI) cancers. The modulation of multiple signaling pathways critical for cancer growth and survival mediates these activities. Nevertheless, human clinical studies of Rg5 have not been addressed before, and there is still considerable ambiguity regarding its pharmacokinetics properties. In addition, a significant shortage in the structure-activity relationship (SAR) of Rg5 has been identified. Therefore, future efforts should focus on further optimization by performing extensive SAR studies to uncover the structural features essential for the potent anticancer activity of Rg5. Thus, this review highlights the value of Rg5 as a potential anticancer drug candidate and identifies the research areas requiring more investigation.

Promising Phytoconstituents in Diabetes-related Wounds: Mechanistic Insights and Implications

BACKGROUND

The onset of diabetes mellitus (DM), a metabolic disorder characterized by high blood glucose levels and disrupted glucose metabolism, results in 20% of people with diabetes suffering from diabetes-related wounds worldwide. A minor wound, such as a cut or abrasion, can lead to infections and complications in diabetic patients. We must understand the mechanism/s contributing to this delayed wound healing to develop effective prevention strategies. The potential benefits of bioactive phytochemicals for diabetic wound healing have been reported in numerous studies.

METHOD

A bioactive compound may have multiple actions, including antioxidants, antiinflammatory, antimicrobial, and angiogenesis. Compounds derived from these plants have shown promising results in wound healing, inflammation reduction, collagen synthesis, and neovascularization improvement.

RESULTS

Consequently, this review provides an update to our understanding of how phytoconstituents promote wound healing in diabetics. A thorough literature review was conducted on diabetes, wound healing, and phytoconstituents for this study. Only English publications until June 2023 were included in the search, which used multiple search engines and the main keywords. Summing up, phytochemical-based interventions might improve the quality of life for diabetics by improving wound healing.

CONCLUSION

However, to fully understand the efficacy and safety of these phytochemicals in managing diabetic wounds, more research and clinical trials are needed.

How to More Effectively Obtain Ginsenoside Rg5: Understanding Pathways of Conversion

Ginsenoside Rg5, a relatively uncommon secondary ginsenoside, exhibits notable pharmacological activity and is commonly hypothesized to originate from the dehydration of Rg3. In this work, we compared different conversion pathways using Rb1, R-Rg3 and S-Rg3 as the raw material under simple acid catalysis. Interestingly, the results indicate that the conversion follows this reaction activity order Rb1 > S-Rg3 > R-Rg3, which is contrary to the common understanding of Rg5 obtained from Rg3 by dehydration. Our experimental results have been fully confirmed by theoretical calculations and a NOESY analysis. The DFT analysis reveals that the free energies of S-Rg3 and R-Rg3 in generating carbocation are 7.56 mol/L and 7.57 mol/L, respectively, which are significantly higher than the free energy of 1.81 mol/L when Rb1 generates the same carbocation. This finding aligns with experimental evidence suggesting that Rb1 is more prone to generating Rg5 than Rg3. The findings from the nuclear magnetic resonance (NMR) analysis suggest that the fatty chains (C22-C27) in R-Rg3 and S-Rg3 adopt a Gauche conformation and an anti conformation with C16-C17 and C13-C17, respectively, due to the relatively weak repulsive van der Waals force. Therefore, the configuration of R-Rg3 is more conducive to the formation of intramolecular hydrogen bonds between 20C-OH and 12C-OH, whereas S-Rg3 lacks this capability. Consequently, this also explains the fact that S-Rg3 is more prone to dehydration to generate Rg5 than R-Rg3. Additionally, our research reveals that the synthetic route of Rg5 derived from protopanaxadiol (PPD)-type ginsenosides (including Rb1, Rb2, Rb3, Rc and Rd) exhibits notable advantages in terms of efficacy, purity and yield when compared to the pathway originating from Rg3. Moreover, this study presents a highly effective and practical approach for the extensive synthesis of Rg5, thereby facilitating the exploration of its pharmacological properties and potential application in drug discovery.

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.

An Efficient Synthesis of Ginsenoside Rg5 via Conversion of PPD Type Saponins: Unusual Application of 4A Molecular Sieves

Ginsenoside Rg5 is a rare secondary ginsenoside with good pharmacological activity. However, preparation of Rg5 is time consuming, gives a low yield and has poor selectivity and efficiency. Therefore, the current study describes an efficient method of preparing ginsenoside Rg5 through conversion of Protopanaxadiol (PPD) type saponins in the presence of a molecular sieve and hydrochloric acid. The PPD type saponins were transformed on the surface of a molecular sieve to obtain ginsenoside Rg5 and most of the generated secondary ginsenoside was dissociates into the reaction solution, avoiding further decomposition. In addition, the optimal experimental conditions were identified to be as follows; 0.5 ml of absolute ethanol, 0.2 mol/L of hydrochloric acid, 12.5 mg of a 4A molecular sieve, a reaction time of 2.5 hours and a reaction temperature of 70 ℃. Under these experimental conditions, yields of upto 63.2% were obtained for ginsenoside Rg5. Moreover, the hydrochloric acid-catalyzed preparation of ginsenoside Rg5 effectively inhibited its decomposition in the presence of a molecular sieve. The method is therefore suitable for laboratory and industrial production with the advantages of large-scale preparation and high-yield.

Ginsenoside Rk1 induces apoptosis and downregulates the expression of PD-L1 by targeting the NF-κB pathway in lung adenocarcinoma

Ginsenoside Rk1 can function as an antitumor modulator that induces apoptosis in lung adenocarcinoma cells by inhibiting NF-κB transcription and triggering cell cycle arrest.

Pharmacokinetics and bioavailability study of ginsenoside Rk1 in rat by liquid chromatography/electrospray ionization tandem mass spectrometry

Ginsenoside Rk1 (Rk1) exhibited various potent biological activities. However, its pharmacokinetic profile in vivo remains unclear. In the present study, a simple and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for determination of Rk1 in rat plasma and applied in a pharmacokinetic study. The sample was precipitated with acetonitrile and separated on a Zorbax Eclipse XDB C18 column (50 × 2.1 mm, 1.8 μm). The mobile phase was composed of 0.1% formic acid in water and acetonitrile at a flow rate of 0.4 mL/min. Rk1 and internal standard (ginsenoside Rg3) were quantitatively monitored with precursor-to-product ion transitions of m/z 765.4 → 441.5 and m/z 783.5 → 621.4, respectively. The assay was linear over the concentration range of 5-1000 ng/mL (r > 0.99) with the LLOQ of 5 ng/mL. Other parameters including intra- and inter-day precision and accuracy, extraction recovery and matrix effect were within the acceptable limits. The analyte was stable under the tested storage conditions. The validated method has been successfully applied to a pharmacokinetic study of Rk1 in rat plasma after intravenous (5 mg/kg) and oral (25 mg/kg, 50 mg/kg) administration. After oral administration, Rk1 could be detected in blood at 30 min and reached the highest concentration at 4.29~4.57 h. Our results demonstrated that Rk1 showed low clearance, moderate half-life (3.09-3.40 h) and low bioavailability (2.87-4.23%). The study will provide information for the further application of Rk1.

Ginseng for the treatment of diabetes and diabetes-related cardiovascular complications: a discussion of the evidence 1

Diabetes mellitus (DM) is a chronic metabolic disorder associated with elevated blood glucose levels due either to insufficient insulin production (type 1 DM) or to insulin resistance (type 2 DM). The incidence of DM around the world continues to rise dramatically with more than 400 million cases reported today. Among the most serious consequences of chronic DM are cardiovascular complications that can have deleterious effects. Although numerous treatment options are available, including both pharmacological and nonpharmacological, there is substantial emerging interest in the use of traditional medicines for the treatment of this condition and its complications. Among these is ginseng, a medicinal herb that belongs to the genus Panax and has been used for thousands of years as a medicinal agent especially in Asian cultures. There is emerging evidence from both animal and clinical studies that ginseng, ginseng constituents including ginsenosides, and ginseng-containing formulations can produce beneficial effects in terms of normalization of blood glucose levels and attenuation of cardiovascular complications through a multiplicity of mechanisms. Although more research is required, ginseng may offer a useful therapy for the treatment of diabetes as well as its complications.

Anti-Inflammatory Effect of Ginsenoside Rh2-Mix on Lipopolysaccharide-Stimulated RAW 264.7 Murine Macrophage Cells

Ginsenoside Rh₂, a protopanaxadiol saponin from ginseng, has been reported to have strong anti-inflammatory activity. However, the concentration of ginsenoside Rh₂ is very low (>0.001%) in the total ginseng extracted, which is not enough for production despite its high pharmacological effects. Thus, in this study, we evaluated the anti-inflammatory effect of ginsenoside Rh₂-mix (GRh₂-mix) on lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cells. From the high-performance liquid chromatography analysis, it was confirmed that the GRh₂-mix was mainly composed of 20(S)-Rh₂, 20(R)-Rh₂, Rk₂, and Rh₃. The LPS-stimulated RAW 264.7 cells were treated with different concentrations of GRh₂-mix (100, 200, 400, 500 μg/mL). The cell counting kit-8 assay showed that the GRh₂-mix treatment increased cell proliferation in LPS-stimulated RAW 264.7 murine macrophage cells. The GRh₂-mix inhibited nitric oxide production in a dose-dependent manner, suggesting an anti-inflammatory effect. Furthermore, reverse transcription polymerase chain reaction and Western blot results also indicated that the GRh₂-mix suppressed inflammatory genes such as iNOS, TNF-α, COX-2, IL-1β, IL-6, and NF-κB. In summary, these results suggest that the GRh₂-mix exhibits anti-inflammatory activity via the downregulation of the NF-κB pathway and has high efficiency with a simple production procedure.

Therapeutic Potential of Ginsenosides as an Adjuvant Treatment for Diabetes

Ginseng, one of the oldest traditional Chinese medicinal herbs, has been used widely in China and Asia for thousands of years. Ginsenosides extracted from ginseng, which is derived from the roots and rhizomes of Panax ginseng C. A. Meyer, have been used in China as an adjuvant in the treatment of diabetes mellitus. Owing to the technical complexity of ginsenoside production, the total ginsenosides are generally extracted. Accumulating evidence has shown that ginsenosides exert antidiabetic effects. In vivo and in vitro tests revealed the potential of ginsenoside Rg1, Rg3, Rg5, Rb1, Rb2, Rb3, compound K, Rk1, Re, ginseng total saponins, malonyl ginsenosides, Rd, Rh2, F2, protopanaxadiol (PPD) and protopanaxatriol (PPT)-type saponins to treat diabetes and its complications, including type 1 diabetes mellitus, type 2 diabetes mellitus, diabetic nephropathy, diabetic cognitive dysfunction, type 2 diabetes mellitus with fatty liver disease, diabetic cerebral infarction, diabetic cardiomyopathy, and diabetic erectile dysfunction. Many effects are attributed to ginsenosides, including gluconeogenesis reduction, improvement of insulin resistance, glucose transport, insulinotropic action, islet cell protection, hepatoprotective activity, anti-inflammatory effect, myocardial protection, lipid regulation, improvement of glucose tolerance, antioxidation, improvement of erectile dysfunction, regulation of gut flora metabolism, neuroprotection, anti-angiopathy, anti-neurotoxic effects, immunosuppression, and renoprotection effect. The molecular targets of these effects mainly contains GLUTs, SGLT1, GLP-1, FoxO1, TNF-α, IL-6, caspase-3, bcl-2, MDA, SOD, STAT5-PPAR gamma pathway, PI3K/Akt pathway, AMPK-JNK pathway, NF-κB pathway, and endoplasmic reticulum stress. Rg1, Rg3, Rb1, and compound K demonstrated the most promising therapeutic prospects as potential adjuvant medicines for the treatment of diabetes. This paper highlights the underlying pharmacological mechanisms of the anti-diabetic effects of ginsenosides.

Ginsenoside Rk1 bioactivity: a systematic review

Ginsenoside Rk1 (G-Rk1) is a unique component created by processing the ginseng plant (mainly Sung Ginseng (SG)) at high temperatures. The aim of our study was to systematically review the pharmacological effects of G-Rk1. We utilized and manually searched eight databases to select in vivo and in vitro original studies that provided information about biological, pharmaceutical effects of G-Rk1 and were published up to July 2017 with no restriction on language or study design. Out of the 156 papers identified, we retrieved 28 eligible papers in the first skimming phase of research. Several articles largely described the G-Rk1 anti-cancer activity investigating "cell viability", "cell proliferation inhibition", "apoptotic activity", and "effects of G-Rk1 on G1 phase and autophagy in tumor cells" either alone or in combination with G-Rg5. Others proved that it has antiplatelet aggregation activities, anti-inflammatory effects, anti-insulin resistance, nephroprotective effect, antimicrobial effect, cognitive function enhancement, lipid accumulation reduction and prevents osteoporosis. In conclusion, G-Rk1 has a significant anti-tumor effect on liver cancer, melanoma, lung cancer, cervical cancer, colon cancer, pancreatic cancer, gastric cancer, and breast adenocarcinoma against in vitro cell lines. In vivo experiments are further warranted to confirm these effects.