Ginsenoside Rg1 protects against Sca-1+ HSC/HPC cell aging by regulating the SIRT1-FOXO3 and SIRT3-SOD2 signaling pathways in a γ-ray irradiation-induced aging mice model

Effect of ginsenoside Rg1 on hematopoietic stem cells in treating aplastic anemia in mice via MAPK pathway

BACKGROUND

Aplastic anemia (AA) presents a significant clinical challenge as a life-threatening condition due to failure to produce essential blood cells, with the current therapeutic options being notably limited.

AIM

To assess the therapeutic potential of ginsenoside Rg1 on AA, specifically its protective effects, while elucidating the mechanism at play.

METHODS

We employed a model of myelosuppression induced by cyclophosphamide (CTX) in C57 mice, followed by administration of ginsenoside Rg1 over 13 d. The investigation included examining the bone marrow, thymus and spleen for pathological changes via hematoxylin-eosin staining. Moreover, orbital blood of mice was collected for blood routine examinations. Flow cytometry was employed to identify the impact of ginsenoside Rg1 on cell apoptosis and cycle in the bone marrow of AA mice. Additionally, the study further evaluated cytokine levels with enzyme-linked immunosorbent assay and analyzed the expression of key proteins in the MAPK signaling pathway via western blot.

RESULTS

Administration of CTX led to significant damage to the bone marrow's structural integrity and a reduction in hematopoietic cells, establishing a model of AA. Ginsenoside Rg1 successfully reversed hematopoietic dysfunction in AA mice. In comparison to the AA group, ginsenoside Rg1 provided relief by reducing the induction of cell apoptosis and inflammation factors caused by CTX. Furthermore, it helped alleviate the blockade in the cell cycle. Treatment with ginsenoside Rg1 significantly alleviated myelosuppression in mice by inhibiting the MAPK signaling pathway.

CONCLUSION

This study suggested that ginsenoside Rg1 addresses AA by alleviating myelosuppression, primarily through modulating the MAPK signaling pathway, which paves the way for a novel therapeutic strategy in treating AA, highlighting the potential of ginsenoside Rg1 as a beneficial intervention.

Protopanaxatriol activates EGFR and HER2 to strengthen the molecules of skin protection in human keratinocytes

BACKGROUND

Protopanaxatriol (PPT) is an important ginsenoside produced by ginseng, a tonic plant used in many areas. PPT has beneficial effects against many disease states including inflammation, diabetes, and cancer. However, PPT's protective effects on skin integrity have been rarely studied. Previously, we reported that PPT can maintain skin moisture through activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. However, the cellular targets for enhancing skin moisturizing effects via PPT are still unknown.

PURPOSE

We wanted to identify the upstream targets of PPT on upregulating moisturizing factor (HAS-2) expression.

STUDY DESIGN

We investigated which upstream proteins can be directly stimulated by PPT to modulate NF-κB, MAPKs and other signaling cascades. Then, the targeted proteins were overexpressed to check the relationship with HAS-2. Next, the cellular thermal shift assay (CETSA) was conducted to check the relationship between targeted proteins and PPT.

METHODS

A human keratinocyte HaCaT were employed to measure the levels of moisturizing factors and the signaling proteins activated by PPT. Transfection conditions were established with DNA constructs expressing epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and their mutants prepared by site-directed mutagenesis. Further investigation on molecular mechanisms was conducted by RT-PCR, luciferase reporter gene assay, CETSA, or Western blot.

RESULTS

We found that PPT can activate the phosphorylation of EGFR and HER2. These stimulations caused Src phosphorylation, which resulted in the activation of phosphoinositide 3-kinases (PI3K)/pyruvate dehydrogenase kinase 1 (PDK1)/protein kinase B (AKT)/NF-κB and MAPKs signaling cascades. Additionally, EGFR and HER2 activation resulted in phosphorylation of signal transducer and activator of transcription 3 (STAT3) and calcium/calmodulin-dependent protein kinase II (CaMKII). This induced the AMP-activated protein kinase alpha (AMPKα) signaling pathway. Additionally, PPT blocked peroxisome proliferator activated receptor gamma (PPARγ), which also contributed to the phosphorylation of Src.

CONCLUSION

Overall, we first found that PPT offers excellent protection of the skin barrier and hydrogen supply in keratinocytes. Moreover, growth factor receptors such as EGFR and HER2 were revealed to be central enzymes to be directly targeted by PPT. These results suggest a potentially valuable role as a cosmetic ingredient.

Probable targets and mechanism of ginsenoside Rg1 for non-alcoholic fatty liver disease: a study integrating network pharmacology, molecular docking, and molecular dynamics simulation

Ginsenoside Rg1 (GRg1), a key bioactive component of medicinal herbs, has shown beneficial effects on non-alcoholic fatty liver disease (NAFLD) and numerous other conditions. Nevertheless, the specific targets that are actively involved and the potential mechanisms underlying NAFLD treatment remain unclear. This study aimed to elucidate the therapeutic effects and mechanism of GRg1 in alleviating NAFLD using a combined approach of network pharmacology and molecular biology validation. The analysis yielded 294 targets for GRg1 and 1293 associated with NAFLD, resulting in 89 overlapping targets. Through protein-protein interactions (PPI) network topology analysis, 10 key targets were identified. Upon evaluating the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analysis, GRg1 may exert therapeutic effects on NAFLD by negatively regulating the apoptotic process, insulin and endocrine resistance, the AGE-RAGE signaling pathway in diabetic complications, and the Estrogen, PI3K/Akt, and MAPK pathways. The three differential gene targets for Akt1, EGFR, and IGF1 were identified through the compound-target network in conjunction with the aforementioned methods. The molecular docking and molecular dynamics (MD) simulations showed that AKT1 and EGFR had a strong binding affinity with GRg1. Overall, our findings point to a novel therapeutic strategy involving NAFLD, with further in vivo and in vitro studies promising to deepen our comprehension and validate its potential advantages.Communicated by Ramaswamy H. Sarma.

The anti-aging mechanism of ginsenosides with medicine and food homology

With the acceleration of global aging and the rise in living standards, the achievement of healthy aging is becoming an imperative issue globally. Ginseng, a medicinal plant that has a long history of dietary intake and remarkable medicinal value, has become a research hotspot in the field of food and medicine. Ginsenosides, especially protopanaxadiol-type saponins and protopanaxatriol-type saponins, are among the most important active ingredients in ginseng. Ginsenosides have been found to exhibit powerful and diverse pharmacological activities, such as antiaging, antitumor, antifatigue and immunity enhancement activities. Their effects in antiaging mainly include (1) promotion of metabolism and stem cell proliferation, (2) protection of skin and nerves, (3) modulation of intestinal flora, (4) maintenance of mitochondrial function, and (5) enhancement of telomerase activity. The underlying mechanisms are primarily associated with the intervention of the signaling pathways in apoptosis, inflammation and oxidative stress. In this review, the mechanism of action of ginsenosides in antiaging as well as the potential values of developing ginsenoside-based functional foods and antiaging drugs are discussed.

Effect of anti-skin disorders of ginsenosides- A Systematic Review

Ginsenosides are bioactive components of Panax ginseng with many functions such as anti-aging, anti-oxidation, anti-inflammatory, anti-fatigue, and anti-tumor. Ginsenosides are categorized into dammarane, oleanene, and ocotillol type tricyclic triterpenoids based on the aglycon structure. Based on the sugar moiety linked to C-3, C-20, and C-6, C-20, dammarane type was divided into protopanaxadiol (PPD) and protopanaxatriol (PPT). The effects of ginsenosides on skin disorders are noteworthy. They play anti-aging roles by enhancing immune function, resisting melanin formation, inhibiting oxidation, and elevating the concentration of collagen and hyaluronic acid. Thus, ginsenosides have previously been widely used to resist skin diseases and aging. This review details the role of ginsenosides in the anti-skin aging process from mechanisms and experimental research.

Development of the Thymus and Kidney and Effects of Resveratrol on Their Aging in a Short-Lived Fish

Annual fishes of the genus Nothobranchius have been widely used in cognitive, behavioral, and genetic studies, and have become an excellent animal model for studying aging. However, the development and degeneration of immune organs in annual fishes and the antagonistic effects of resveratrol remain unclear. In the present study, the development of thymus and kidney was investigated systematically using Nothobranchius guentheri from larvae, juveniles, and young and old fish with hematoxylin and eosin staining. We found that thymus primordium was observed first in the larvae at 2 days after hatching (dah). After the lymphoid cells became evident at 5 dah, the thymus acquired an irregular shape at 7 dah. Then it formed a wedge shape at 15 dah. Thymus looked as homogeneous distribution of lymphocytes at 1 month old, and it differentiated into cortex and medulla approximately in 2-month-old fish. Combined with TUNEL and senescence-associated β-galactosidase (SA-β-gal) staining, it showed the degeneration of the thymus appeared in 4-month-old fish. Kidney primordium appeared on 1 dah, and the glomerulus was visible at 7 dah. The nephrogenic activity was most apparent in 1-month-old fish. A large hematopoietic tissue was arranged in the renal interstitium in 2- and 3-month-old fish. In 6-month-old fish, the kidney structure became less dense. By 12 months, the kidney exhibited the most pronounced histological characteristics of aging. Feeding resveratrol ameliorated renal fibrosis and SA-β-gal staining with age, increased SIRT1 and SIRT3 expression, and decreased the levels of NF-κB and inflammatory factors in thymus and kidney of the fish. We provided basic data for the development and degeneration of immune organs and resveratrol's anti-aging effects in short-lived fish.

Ginsenosides on stem cells fate specification-a novel perspective

Recent studies have demonstrated that stem cells have attracted much attention due to their special abilities of proliferation, differentiation and self-renewal, and are of great significance in regenerative medicine and anti-aging research. Hence, finding natural medicines that intervene the fate specification of stem cells has become a priority. Ginsenosides, the key components of natural botanical ginseng, have been extensively studied for versatile effects, such as regulating stem cells function and resisting aging. This review aims to summarize recent progression regarding the impact of ginsenosides on the behavior of adult stem cells, particularly from the perspective of proliferation, differentiation and self-renewal.

Ex vivo reprogramming of human hematopoietic stem cells is accompanied by increased transcripts of genes regulating metabolic integrity

The regenerative potential of human hematopoietic stem cells (HSCs) is functionally defined by their ability to provide life-long blood cell production and to repopulate myeloablated allogeneic transplant recipients. The expansion of HSC numbers is dependent not only on HSC divisions but also on a coordinated adaptation of HSCs to metabolic stress. These variables are especially critical during the ex vivo culture of HSCs with cytokine combinations, which frequently results in HSC exhaustion. We have previously reported that human CD34⁺ hematopoietic stem and progenitor cells (HSPCs) can be efficiently reprogrammed ex vivo and that the number of phenotypic HSCs with long-term repopulation capacity is expanded in the presence of a combination of cytokines and an epigenetic modifier. Here, we present evidence that ex vivo HSC reprogramming and maintenance is accompanied by increased transcripts of genes regulating metabolic integrity, including SIRT1 and SIRT3.

Regulation of radiation-induced liver damage by modulation of SIRT-1 activity: In vivo rat model

Silent information regulator 1 (SIRT-1), a nicotinamide adenine dinucleotide-dependent deacetylase, was found to regulate cell apoptosis, inflammation, and oxidative stress response in living organisms. Therefore, the role of SIRT-1 in regulating forkhead box O/poly ADP-ribose polymerase-1 (FOXO-1/PARP-1) signaling could provide the necessary validation for developing new pharmacological targets for the promotion or inhibition of SIRT-1 activity toward radiation sensitivity. In the present study, the SIRT-1 signaling pathway is being investigated to study the possible modulatory effect of resveratrol (RSV, SIRT-1 activator) versus nicotinamide (NAM, SIRT-1 inhibitor) in case of liver damage induced by whole-body gamma irradiation. Rats were exposed to 6 Gy gamma radiation after being pretreated with either RSV (10 mg/kg/day) or NAM (100 mg/kg/day) for 5 days, and subsequent examining hepatic morphological changes and apoptotic markers were assessed. The expression of SIRT-1, FOXO-1, and cleaved PARP-1 in the liver was analyzed. RSV improved radiation-induced apoptosis, mitochondrial dysfunction, and inflammation signified by low expression of caspase-3, lactate dehydrogenase, complex-I activity, myeloperoxidase, and total nitric oxide content. RSV increased the expression of SIRT-1, whereas cleaved PARP-1 and FOXO-1 were suppressed. These protective effects were suppressed by inhibition of SIRT-1 activity using NAM. These findings suggest that RSV can attenuate radiation-induced hepatic injury by reducing apoptosis and inflammation via SIRT-1 activity modulation.

Inhibitory effects and molecular mechanisms of ginsenoside Rg1 on the senescence of hematopoietic stem cells

Hematopoietic stem cells (HSCs) produce all blood cell lineages and maintain life-long hematopoiesis. However, the self-renewal ability and differentiation capacity of HSCs reduces with age. The senescence of HSCs can lead to the imbalance of hematopoietic homeostasis and immune disorder and induce a variety of age-related diseases. Recent studies have shown that therapeutic interventions targeting the senescence of HSCs may prevent disease progression. Ginsenoside Rg1 (Rg1), extracted from roots or stems of ginseng, has beneficial antiaging activities. It has been reported that Rg1 can inhibit the senescence of HSCs. Here, we reviewed recent advances of Rg1 in inhibiting the senescence of HSCs and discussed related molecular mechanisms. Bioinformatics and network databases have been widely applied to drug discoveries. Here, we predicted potential antiaging targets of Rg1 explored by bioinformatic methods, which may help discover new targets of Rg1 and provide novel strategies for delaying the aging process of HSCs.

Ageing, cellular senescence and chronic kidney disease: experimental evidence

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is often viewed as an accelerated and premature ageing of the kidney, as they share common pathological features characterized by cellular senescence. In this review, we summarize the experimental evidence linking cellular senescence to the pathobiology of kidney ageing and CKD, and discuss the strategies for targeting senescent cells in developing therapeutics for ageing-related kidney disorders.

RECENT FINDINGS

Kidney ageing and CKD are featured with increased cellular senescence, an irreversible state of cell cycle arrest and the cessation of cell division. Senescent cells secrete a diverse array of proinflammatory and profibrotic factors known as senescence-associated secretory phenotype (SASP). Secondary senescence can be induced by primary senescent cells via a mechanism involving direct contact or the SASP. Various senolytic therapies aiming to selectively remove senescent cells in vivo have been developed. Senostatic approaches to suppress senescence or inhibit SASP, as well as nutrient signalling regulators are also validated in animal models of ageing.

SUMMARY

These recent studies provide experimental evidence supporting the notion that accumulation of senescent cells and their associated SASP is a main driver leading to structural and functional organ degeneration in CKD and other ageing-related disorder.

Ginsenoside Rg1 exerts anti‑apoptotic effects on non‑alcoholic fatty liver cells by downregulating the expression of SGPL1

Non‑alcoholic fatty liver disease (NAFLD) has a high incidence, and can lead to liver cirrhosis and even hepatocellular carcinoma in severe cases. To the best of our knowledge, there is currently no safe and effective treatment for the management of this disease. Ginsenoside Rg1 (Rg1) is an active monomer derived from ginseng and notoginseng. In the present study, HHL‑5 hepatocytes were used to establish an in vitro cell model of NAFLD by medium‑ and long‑chain fat emulsion treatment, and the effects of Rg1 on adipose accumulation, apoptosis and the expression levels of apoptosis‑related proteins in HHL‑5 hepatocytes were examined. The results demonstrated that Rg1 inhibited the accumulation of fat in HHL‑5 cells, while inhibiting apoptosis, and Rg1 downregulated the expression levels of the pro‑apoptotic protein Bax and upregulated the expression levels of the anti‑apoptotic protein Bcl‑2, indicating that Rg1 could promote the stability or integrity of mitochondria and exert an anti‑apoptotic effect by regulating Bcl‑2 family proteins. In addition, Rg1 markedly downregulated the expression levels of sphingosine‑1‑phosphate lyase 1 (SGPL1), a key enzyme in the sphingosine signaling pathway, in HHL‑5 cells with steatosis, and increased the expression levels of the downstream pro‑survival signals phosphorylated (p‑)Akt and p‑Erk1/2. Furthermore, overexpression of SGPL1 abolished the anti‑apoptotic effect of Rg1 on SGPL1‑overexpressing HHL‑5 cells with steatosis, and downregulated the expression levels of pro‑survival proteins, such as Bcl‑2, p‑Akt and p‑Erk1/2, whereas the expression levels of pro‑apoptotic Bax were markedly increased. In conclusion, although there are some reports regarding the protective effect of Rg1 on fatty liver cells, to the best of our knowledge, the present study is the first to report that Rg1 may exert an anti‑apoptotic effect on fatty liver cells by regulating SGPL1 in the sphingosine signaling pathway. Rg1 is the main component of the prescription drug Xuesaitong in China; therefore, the findings of the present study may provide a theoretical molecular basis for the use of Rg1 or Xuesaitong in the treatment of patients with NAFLD.

Bronchial epithelial SIRT1 deficiency exacerbates cigarette smoke induced emphysema in mice through the FOXO3/PINK1 pathway

Purpose: Cellular senescence and mitochondrial fragmentation are thought to be crucial components of the cigarette smoke(CS)-induced responses that contribute to the chronic obstructive pulmonary disease (COPD) development as a result of accelerated premature aging of the lung. Although there have been a few reports on the role of sirtuin 1(SIRT1) in mitochondrial homeostasis, senescence and inflammation, whether SIRT1/FOXO3/PINK1 signaling mediated mitophagy ameliorates cellular senescence in COPD is still unclear. This study aimed to ascertain whether SIRT1 regulates cellular senescence via FOXO3/PINK1-mediated mitophagy in COPD. Methods: To investigate the effect of CS exposure and SIRT1 deficiency on mitophagy and senescence in the lung, a SIRT1 knockout(KO) mouse model was used. Airway resistance, cellular senescence mitochondrial injury, mitophagy, cellular architecture and protein expression levels in lung tissues, from SIRT1 KO and wild-type(WT) COPD model mice exposed to CS for 6 months were examined by western blotting, histochemistry, immunofluorescence and transmission electron microscopy(TEM). Results: In CS exposed mice, SIRT1 deficiency exacerbated airway resistance and cellular senescence, increased FOXO3 acetylation and decreased PINK1 protein levels and attenuated mitophagy. Mechanistically, the damaging effect of SIRT1 deficiency on lung tissue was attributed to increased FOXO3 acetylation and decreased PINK1 levels, and attenuated mitophagy. In vitro, mitochondrial damage and cellular sensitivity in response to CS exposure were more severe in control cells than in cells treated with aSIRT1 activator. SIRT1 activation SIRT1 activation decreased FOXO3 acetylation and increased the protein levels of PINK1 and enhanced mitophagy. Conclusion: These results demonstrated that the detrimental effects of SIRT1 deficiency on cell senescence associated with insufficient mitophagy, and involved the FOXO3/PINK1 signaling pathway.

Vitamin D3 protects against nitrogen mustard-induced apoptosis of the bronchial epithelial cells via activating the VDR/Nrf2/Sirt3 pathway

Respiratory system injury is the main cause of mortality for nitrogen mustard (NM)-induced damage. Previous studies indicate that reactive oxygen species (ROS) participates in NM-mediated respiratory injuries, but the detailed mechanism is not quite clear. Human bronchial epithelial cell lines 16HBE and BEAS-2B were treated with HN2, a type of NM. In detail, it was shown that HN2 treatment induced impaired cell viability, excessive mitochondrial ROS production and enhanced cellular apoptosis in bronchial epithelial cells. Moreover, impaired Sirt3/SOD2 axis was observed upon HN2 treatment, with decreased Sirt3 and increased acetylated SOD2 expression levels. Sirt3 overexpression partially ameliorated HN2-induced cell injury. Meanwhile, vitamin D3 treatment partially attenuated HN2-induced apoptosis and improved the mitochondrial functions upon HN2 intervention. In addition, HN2 exposure decreased VDR expression, thus inhibiting the Nrf2 phosphorylation and Sirt3 activation. Inhibition of Nrf2 or Sirt3 could decrease the protective effects of vitamin D3 and enhance mitochondrial ROS production via modulating mitochondrial redox balance. In conclusion, impaired VDR/Nrf2/Sirt3 axis contributed to NM-induced apoptosis, while vitamin D3 supplementation provides protective effects via the activation of VDR and the improvement of mitochondrial functions. This study provides novel mechanism and strategy for NM exposure-induced pulmonary injuries.

Ginsenoside Rg1 can restore hematopoietic function by inhibiting Bax translocation-mediated mitochondrial apoptosis in aplastic anemia

The present study investigated, the anti-apoptotic activity of Ginsenoside Rg1 (Rg1) via inhibition of Bax translocation and the subsequent recovery of hematopoietic function. Mitochondrial apoptosis in bone marrow mononuclear cells (BMNCs) was observed in aplastic anemia (AA) patients. To establish a mouse model of AA, BALB/c mice were transplanted with lymph node cells from DBA/2 donor mice via vein injection after treatment with Co60 γ-radiation. After treatment with Rg1 for 14 days, the peripheral blood and Lin–Sca-1 + c-Kit + (LSK) cell counts of the treated group were increased compared with those of the untreated model mice. In in vivo and in vitro tests of LSKs, Rg1 was found to increase mitochondrial number and the ratio of Bcl-2/Bax and to decrease damage to the mitochondrial inner and outer membranes, the mitochondrial Bax level and the protein levels of mitochondrial apoptosis-related proteins AIF and Cyt-C by decreasing the ROS level. Rg1 also improved the concentration–time curve of MAO and COX and levels of ATP, ADP and AMP in an in vitro test. In addition, high levels of Bax mitochondrial translocation could be corrected by Rg1 treatment. Levels of markers of mitochondrial apoptosis in the Rg1-treated group were significantly better than those in the AA model group, implying that Rg1 might improve hematopoietic stem cells and thereby restore hematopoietic function in AA by suppressing the mitochondrial apoptosis mediated by Bax translocation.

Targeting Sirtuin 1 signaling pathway by ginsenosides

ETHNOPHARMACOLOGICAL RELEVANCE

Ginseng is a kind of traditional Chinese herbal medicine, known as "king of herbs" and widely used in China, South Korea, and other Asian countries. Ginsenosides are one of active components of Panax ginseng Meyer, which have many pharmacological effects, such as enhancing memory, improving immunity and cardiovascular system, delaying aging, and preventing cancer.

AIMS OF THE REVIEW

This review aims to summarize the recent findings for ginsenosides targeting Sirtuin 1 (SIRT1) signaling pathway for the prevention and treatment of a series of diseases.

MATERIALS AND METHODS

An up-to-August 2020 search was carried out in databases such as PubMed, ScienceDirect, Google Scholar, China National Knowledge Infrastructure, and classic books of traditional Chinese medicine using the keywords: "SIRT1", and/or paired with "ginseng", and "ginsenosides".

RESULTS

SIRT1 is a class-III histone deacetylase (HDAC), a nicotinamide adenine dinucleotide (NAD⁺)-dependent enzyme, which is deeply involved in a series of pathological processes. Based on specific intracellular localization, SIRT1 has various cytoplasmic and nuclear targets and plays a potential role in energy metabolism, oxidative stress, inflammation, tumorigenesis, and aging. Ginsenosides are generally classified into three groups and microbially transformed to final metabolites. Among of them, most ginsenosides have been reported as SIRT1 activators, especially those ginsenosides with two glucopyranosyl groups on the C-3 position. Importantly, many ginsenosides can be used to prevent and treat oxidative stress, inflammation, aging, tumorigenesis, depression, and others by targeting SIRT1 signaling pathway.

CONCLUSIONS

This paper reviews recent evidences of ginsenosides targeting SIRT1 for the first time, which could provide new insights on the preclinical and clinical researches for ginsenosides against multiple disorders.