Ginsenoside 20(R)-Rg3 enhances natural killer cell activity by increasing activating receptor expression through the MAPK/ERK signaling pathway

20(S)-ginsenoside Rg3 alleviates DSS-induced colitis by promoting ERK-dependent maturation of MDSCs into M2 macrophages

Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells with immunosuppressive functions that play various roles in tumors and inflammatory diseases. In colitis, MDSCs accumulate in the inflamed colon, where they mature into M2-polarized macrophages and modulate inflammatory responses. Ginsenosides, active components of ginseng, have been shown to display colitis-alleviating effects in mouse models. However, the detailed mechanisms underlying these effects are incompletely understood. This study explores the impact of ginsenosides on MDSC functions and differentiation, focusing on their potential to mitigate inflammatory symptoms in colitis. Among the 15 ginsenosides tested, Rg3(R) and Rg3(S) were found to promote the maturation of MDSCs into M2 macrophages at non-cytotoxic concentrations. This was confirmed by the increased expression of ARG1, an immunosuppressive marker. These effects were attributed to the activation of the ERK pathway, as confirmed by selective ERK inhibition. In a DSS-induced colitis mouse model, oral administration of Rg3(S) alleviated disease severity and increased MDSC differentiation into M2 macrophages in colon lamina propria, highlighting its therapeutic potential colitis.

20(R)-ginsenoside Rg3 alleviates diabetic retinal injury in T2DM mice by attenuating ROS-mediated ER stress through the activation of the Nrf2/HO-1 axis

BACKGROUND

Although our previous work confirmed 20(R)-ginsenoside Rg3 (R-Rg3), which is an active ingredient in the Panax Ginseng C.A. Meyer, to have good anti-diabetic activity, its beneficial effect on diabetic retinal injury was found to be limited.

PURPOSE

This study aims to investigate the protective effects of R-Rg3 on diabetes-induced retinal injury and the associated molecular mechanisms of action.

METHODS

Diabetic retinal injury was induced in mice using a combination of a high-fat diet (HFD) and intraperitoneal injection of streptozotocin (STZ). R-Rg3 (10 and 20 mg/kg) was subsequently administered for 6 weeks. The human retinal endothelial cells (HRECs) were subjected to high glucose (HG)-induced injury for the in vitro analysis and treated with R-Rg3 (4, 8, 16 μM), antioxidant N-Acetylcysteine (NAC, 1 mM) and Nrf2 inhibitor ML385 (5 μM). The mice retinas then underwent functional and histopathological analysis. Expression levels of proteins related to the Nrf2/HO-1 axis, tight junction proteins, endoplasmic reticulum (ER) stress and the apoptosis in retinal tissue and HRECs were determined by western blot. Expressions of ZO-1 and Nrf2 in the retina and HRECs were assessed by immunofluorescence. Additional evaluations included measuring body weights, fasting blood glucose (FBG), lipid levels and oxidative markers.

RESULTS

The results showed 6 weeks of R-Rg3 treatment significantly restored the functional changes and redox system imbalance that was induced by HFD/STZ in mice. R-Rg3 was also found to significantly reduce retinal barrier damage and thickness changes resulting from hyperglycaemia exposure. At the same time, R-Rg3 also protected HRECs from HG-induced damage. R-Rg3 could also activate Nrf2/HO-1 axis and inhibit endoplasmic reticulum stress as a means of alleviating retinal endothelial cells apoptosis. The molecular docking results also demonstrated that R-Rg3 had a good binding ability with Nrf2.

CONCLUSION

Our study suggested Nrf2/HO-1 axis might be crucial for the ability of R-Rg3 to prevent diabetic retinal injury.

Exercise: a non-drug strategy of NK cell activation

Natural killer (NK) cells are a critical component of the innate immune system and one of the immune cells most sensitive to exercise. So far, it is widely believed that moderate exercise can significantly enhance the proliferation and activity of NK cells, strengthening immune function. However, the impact of exercise on NK cells is a dynamic and complex process. In addition to the type of exercise, the frequency, intensity, and duration of exercise are also key factors. This article not only briefly summarizes the activation mechanisms of NK cells but also delves into the potential importance of exercise as a non-pharmacological strategy in modulating NK cell activity and enhancing the immune system. Emerging studies have indicated that the timing and regularity of exercise bouts might also influence NK cell responses. Moreover, the interaction between exercise and other components of the immune system, such as cytokines and chemokines, could further modulate the functionality of NK cells. The above research is of crucial significance for achieving a deeper understanding of the intricate connection between exercise and NK cell function, as well as the development of effective health promotion strategies. In addition, further research is needed to investigate the effects of long-term exercise on NK cell function and the interaction between exercise and NK cell-mediated immune responses. Translating these research findings into precisely tailored exercise programs for specific populations, taking into account factors like age, health status, and genetic predisposition, could potentially offer unprecedented prospects for further advancements in this burgeoning field of study.

Lacticaseibacillus casei K11 exerts immunomodulatory effects by enhancing natural killer cell cytotoxicity via the extracellular regulated-protein kinase pathway

PURPOSE

Probiotics can serve as immunomodulators that regulate the activation of immune cells. This study aimed to screen potential probiotic strains that can enhance NK cell toxicity to improve host immunity.

METHODS

In this investigation, we examined three potential probiotic strains, namely Lactiplantibacillus plantarum YZX21 (YZX21), Bifidobacterium bifidum FL-276.1 (FL-276.1) and Lacticaseibacillus casei K11 (K11), to assess their capacity in modulating NK cytotoxicity both in vitro and in vivo, while elucidating the underlying mechanisms involved.

RESULTS

The findings demonstrated that K11 exhibited superior efficacy in enhancing NK cytotoxicity. Subsequent analysis revealed that K11 significantly augmented the secretion of perforin and granzyme B by NK cells through activation of receptors NKp30 and NKp46 via the extracellular signal-regulated kinase (ERK) pathway. Furthermore, heat-inactivated K11 also enhanced NK cell activity to an extent comparable to live bacteria, with lipoteichoic acid from K11 identified as a crucial factor mediating the activation of NK cell cytotoxicity.

CONCLUSION

Our study suggests that K11 may have potential applications as probiotics or postbiotics for regulating NK cell cytotoxicity to enhance immunity.

Ginsenoside Rg3 induces mesangial cells proliferation and attenuates apoptosis by miR-216a-5p/MAPK pathway in diabetic kidney disease

BACKGROUND

Ginsenoside Rg3 is an active saponin isolated from ginseng, which can reduce renal inflammation. However, the role and mechanism of Rg3 in diabetic kidney disease (DKD) are far from being studied.

METHODS

The effects of Rg3 and miR-216a-5p on the proliferation, apoptosis, and MAPK pathway in high glucose (HG)-induced SV40 MES 13 were monitored by CCK-8, TUNEL staining, and western blot.

RESULTS

Rg3 treatment could accelerate proliferation and suppress apoptosis in HG-induced SV40 MES. Moreover, miR-216a-5p inhibition also could alleviate renal injury, prevent apoptosis, and activate the MAPK pathway in kidney tissues of diabetic model mice.

CONCLUSION

Rg3 could attenuate DKD progression by downregulating miR-216a-5p, suggesting Rg3 and miR-216a-5p might be the potential drug and molecular targets for DKD therapy.

Multi-layered effects of Panax notoginseng on immune system

Recent research has demonstrated the immunomodulatory potential of Panax notoginseng in the treatment of chronic inflammatory diseases and cerebral hemorrhage, suggesting its significance in clinical practice. Nevertheless, the complex immune activity of various components has hindered a comprehensive understanding of the immune-regulating properties of Panax notoginseng, impeding its broader utilization. This review evaluates the effect of Panax notoginseng to various types of white blood cells, elucidates the underlying mechanisms, and compares the immunomodulatory effects of different Panax notoginseng active fractions, aiming to provide the theory basis for future immunomodulatory investigation.

Gintonin upregulates cytokine production and expression of NKp30, NKp44 and NKp44 related to natural killer cell activity on immunosuppressive rat

The objective of the study is to estimate the potential of gintonin, as an immune enhancing agent through natural killer cell (NK cell) activity in cyclophosphamide (CY)-induced immunosuppressive animals. Accumulated results reveals that, gintonin attenuated CY-induced immunosuppression and it might modulate NK cell activity to boost the immunity.

The development of nanocarriers for natural products

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Unveiling the experimental proof of the anticancer potential of ginsenoside Rg3 (Review)

Ginsenoside Rg3 (GS-Rg3), a sterol molecule isolated from ginseng, has demonstrated various immunological properties, including inhibition of cancer cell proliferation and metastasis, reversal of drug resistance and enhancement of chemotherapy sensitivity. The recent surge in attention towards GS-Rg3 can be attributed to its potential as an antitumor angiogenesis agent and as a therapeutic candidate for immunotherapy. The development of GS-Rg3 as an agent for these purposes has accelerated research on its mechanisms of action. The present review summarizes recent studies investigating the antitumor activity of GS-Rg3 and its underlying mechanisms, as well as providing essential information for future studies on GS-Rg3.

Research Progress on the Antitumor Molecular Mechanism of Ginsenoside Rh2

Cancer has evolved into a substantial public health concern as the second-leading cause of mortality globally. Radiotherapy and chemotherapy have been the two most widely used cancer therapies in recent years; however, both have drawbacks. Therefore, the focus has shifted to the creation of herbal medicines, the extraction of active ingredients, replacement therapy, and the adverse effects of these medications. Ginsenoside Rh2, which is extracted from ginseng, has been identified in many cancer cells. The immune system of the body is strengthened by ginsenoside Rh2, which can also cause the proliferation, death, and differentiation of tumor cells through various pathways. For instance, it inhibits the expression of the NF-[Formula: see text]B signaling pathway and induces cell apoptosis, affects the expression levels of mitochondrial apoptosis proteins Bcl-2 and Bax, and cooperates with the PD-1 blockade to reactivate T cells to promote an antitumor immune response. Furthermore, ginsenosides Rh2 has the effect of reversing the toxic effect of chemotherapy drugs on normal cells, reducing myocardial damage, and relieving bone marrow function suppression. For clinical applications, it is mainly used as an adjuvant drug for preoperative neoadjuvant chemotherapy, postoperative adjuvant chemotherapy, and rescue treatment of advanced cancer. This paper summarizes the pharmacological action and mechanism of ginsenosides Rh2 in all kinds of cancer and looks forward to its future development and application.

Exploring 3-O-glycosylations of 20(R)-dammarane ginsenosides and the catalytic mechanism underlying the stereoselectivity with the combined assistance of AlphaFold 2 and molecular docking

Glycosylation at C3-OH is the favorable modification for pharmaceutical activities and diversity expansion of 20(R)-dammarane ginsenosides. The 3-O-glycosylation, exclusively occurring in 20(R)-PPD ginsenosides, has never been achieved in 20(R)-PPT ginsenosides. Herein, 3-O-glycosylation of 20(R)-PPT enabled by a glycosyltransferase (GT) OsSGT2 was achieved with the combined assistance of AlphaFold 2 and molecular docking. Firstly, we combined AlphaFold2 algorithm and molecular docking to predict interactions between 20(R)-PPT and candidate GTs. A catalytically favorable binding geometry was thus identified in the OsSGT2-20(R)-PPT complex, suggesting OsSGT2 might act on 20(R)-PPT. The enzymatic assays demonstrated that OsSGT2 reacted with varied sugar donors to form 20(R)-PPT 3-O-glycosides, exhibiting donor promiscuity. Additionally, OsSGT2 displayed acceptor promiscuity, catalyzing 3-O-glucosylation of 20(R/S)-PPT, 20(R/S)-PPD and 20(R/S)-Rh1, respectively. Protein engineering on OsSGT2 was thus performed to probe its catalytic mechanism underlying its stereoselectivity. The W207A mutant preferred 20(S)-dammarane aglycons, while F395Q/A396G(QG) displayed a conversion enhancement towards both 20(R/S)-dammarane aglycons. The QG mutant was then used to synthesize 20(R)-PPT 3-O-glucoside, which displayed a moderate angiotensin-converting enzyme inhibitory effect with an IC50 of 27.5 ± 4.7 μM, superior to that of its 20(S)-epimer, with the combined assistance of target fishing and reverse docking. The water solubility of 20(R)-PPT 3-O-glucoside increased as well.

Potential Immunoregulatory Mechanism of Plant Saponins: A Review

Saponins are extracted from different parts of plants such as seeds, roots, stems, and leaves and have a variety of biological activities including immunomodulatory, anti-inflammatory effects, and hypoglycemic properties. They demonstrate inherent low immunogenicity and possess the capacity to effectively regulate both the innate and adaptive immune responses. Plant saponins can promote the growth and development of the body's immune organs through a variety of signaling pathways, regulate the activity of a variety of immune cells, and increase the secretion of immune-related cytokines and antigen-specific antibodies, thereby exerting the role of immune activity. However, the chemical structure of plant saponins determines its certain hemolytic and cytotoxicity. With the development of science and technology, these disadvantages can be avoided or reduced by certain technical means. In recent years, there has been a significant surge in interest surrounding the investigation of plant saponins as immunomodulators. Consequently, the objective of this review is to thoroughly examine the immunomodulatory properties of plant saponins and elucidate their potential mechanisms, with the intention of offering a valuable point of reference for subsequent research and advancement within this domain.

Ginsenosides in cancer: Targeting cell cycle arrest and apoptosis

Despite the existence of extensive clinical research and novel therapeutic treatments, cancer remains undefeated and the significant cause of death worldwide. Cancer is a disease in which growth of cells goes out of control, being also able to invade other parts of the body. Cellular division is strictly controlled by multiple checkpoints like G1/S and G2/M which, when dysregulated, lead to uncontrollable cell division. The current remedies which are being utilized to combat cancer are monoclonal antibodies, chemotherapy, cryoablation, and bone marrow transplant etc. and these have also been greatly disheartening because of their serious adverse effects like hypotension, neuropathy, necrosis, leukemia relapse and many more. Bioactive compounds derived from natural products have marked the history of the development of novel drug therapies against cancer among which ginsenosides have no peer as they target several signaling pathways, which when abnormally regulated, lead to cancer. Substantial research has reported that ginsenosides like Rb1, Rb2, Rb3, Rc, Rd, Rg3, Rh2 etc. can prevent and treat cancer by targeting different pathways and molecules by induction of autophagy, neutralizing ROS, induction of cancerous cell death by controlling the p53 pathway, modulation of miRNAs by decreasing Smad2 expression, regulating Bcl-2 expression by normalizing the NF-Kb pathway, inhibition of inflammatory pathways by decreasing the production of cytokines like IL-8, causing cell cycle arrest by restricting cyclin E1 and CDC2, and induction of apoptosis during malignancy by decreasing β-catenin levels etc. In this review, we have analyzed the anti-cancer therapeutic potential of various ginsenoside compounds in order to consider their possible use in new strategies in the fight against cancer.

New perspective on the immunomodulatory activity of ginsenosides: Focus on effective therapies for post-COVID-19

More than 700 million confirmed cases of Coronavirus Disease-2019 (COVID-19) have been reported globally, and 10-60% of patients are expected to exhibit "post-COVID-19 symptoms," which will continue to affect human life and health. In the absence of safer, more specific drugs, current multiple immunotherapies have failed to achieve satisfactory efficacy. Ginseng, a traditional Chinese medicine, is often used as an immunomodulator and has been used in COVID-19 treatment as a tonic to increase blood oxygen saturation. Ginsenosides are the main active components of ginseng. In this review, we summarize the multiple ways in which ginsenosides affect post-COVID-19 symptoms, including inhibition of lipopolysaccharide, tumor necrosis factor signaling, modulation of chemokine receptors and inflammasome activation, induction of macrophage polarization, effects on Toll-like receptors, nuclear factor kappa-B, the mitogen-activated protein kinase pathway, lymphocytes, intestinal flora, and epigenetic regulation. Ginsenosides affect virus-mediated tissue damage, local or systemic inflammation, immune modulation, and other links, thus alleviating respiratory and pulmonary symptoms, reducing the cardiac burden, protecting the nervous system, and providing new ideas for the rehabilitation of patients with post-COVID-19 symptoms. Furthermore, we analyzed its role in strengthening body resistance to eliminate pathogenic factors from the perspective of ginseng-epidemic disease and highlighted the challenges in clinical applications. However, the benefit of ginsenosides in modulating organismal imbalance post-COVID-19 needs to be further evaluated to better validate the pharmacological mechanisms associated with their traditional efficacy and to determine their role in individualized therapy.

Research Progress on Anti-Inflammatory Mechanisms of Black Ginseng

In recent years, black ginseng, a new type of processed ginseng product, has attracted the attention of scholars globally. Ginsenoside and ginseng polysaccharide, the main active substances of black ginseng, have been shown to carry curative effects for many diseases. This article focuses on the mechanism of their action in anti-inflammatory response, which is mainly divided into three aspects: activation of immune cells to exert immune regulatory response; participation in inflammatory response-related pathways and regulation of the expression level of inflammatory factors; effect on the metabolic activity of intestinal flora. This study identifies active anti-inflammatory components and an action mechanism of black ginseng showing multi-component, multi-target, and multi-channel characteristics, providing ideas and a basis for a follow-up in-depth study of its specific mechanism.

Research progress of ginseng in the treatment of gastrointestinal cancers

Cancer has become one of the major causes of human death. Several anticancer drugs are available; howeve their use and efficacy are limited by the toxic side effects and drug resistance caused by their continuous application. Many natural products have antitumor effects with low toxicity and fewer adverse effects. Moreover, they play an important role in enhancing the cytotoxicity of chemotherapeutic agents, reducing toxic side effects, and reversing chemoresistance. Consequently, natural drugs are being applied as potential therapeutic options in the field of antitumor treatment. As natural medicinal plants, some components of ginseng have been shown to have excellent efficacy and a good safety profile for cancer treatment. The pharmacological activities and possible mechanisms of action of ginseng have been identified. Its broad range of pharmacological activities includes antitumor, antibacterial, anti-inflammatory, antioxidant, anti-stress, anti-fibrotic, central nervous system modulating, cardioprotective, and immune-enhancing effects. Numerous studies have also shown that throuth multiple pathways, ginseng and its active ingredients exert antitumor effects on gastrointestinal (GI) tract tumors, such as esophageal, gastric, colorectal, liver, and pancreatic cancers. Herein, we introduced the main components of ginseng, including ginsenosides, polysaccharides, and sterols, etc., and reviewed the mechanism of action and research progress of ginseng in the treatment of various GI tumors. Futhermore, the pathways of action of the main components of ginseng are discussed in depth to promote the clinical development and application of ginseng in the field of anti-GI tumors.