Hypoglycemic and Hypolipidemic Effects of Malonyl Ginsenosides from American Ginseng (Panax quinquefolius L.) on Type 2 Diabetic Mice

The Active Ingredient Catalpol in Rehmannia glutinosa Reduces Blood Glucose in Diabetic Rats via the AMPK Pathway

Background

Type 2 diabetes mellitus (T2DM) poses a huge threat to population health globally, and more drugs need to be explored for treatment. In this study, we investigated the mechanism of active ingredient catalpol in Rehmannia glutinosa on reduces blood glucose in diabetic.

Methods

The T2DM model was constructed by intraperitoneal injection of streptozotocin into Sprague-Dawley (SD) rats, which were randomly grouped into diabetes model group, pioglitazone group, Rehmannia glutinosa group, catalpol high-dose group, catalpol low-dose group and normal control group.The intervention was continued for 28 d, and changes in body weight, fasting blood glucose, insulin and lipid levels were observed.

Results

Of all the drugs, pioglitazone had the most pronounced hypoglycemic effect, which began to decline after 2 weeks of treatment in the low-dose catalpol group and had no hypoglycemic effect in the high-dose catalpol group. Among them, Rehmannia glutinosa was able to increase serum triglyceride level, and pioglitazone effectively reduced total cholesterol level in rats. The low dose of catalpol decreased the concentration of low-density lipoprotein cholesterol (LDL), while the high dose of catalpol increased the concentration of LDL.

Conclusion

As an active ingredient in Rehmannia glutinosa, catalpol has the potential to lower blood glucose and improve blood lipids in diabetes treatment, and its action may be achieved by regulating the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway, which provides a new idea for the development of new diabetes therapeutic approaches.

Increasing the Amounts of Bioactive Components in American Ginseng (Panax quinquefolium L.) Leaves Using Far-Infrared Irradiation

Both the roots and leaves of American ginseng contain ginsenosides and polyphenols. The impact of thermal processing on enhancing the biological activities of the root by altering its component composition has been widely reported. However, the effects of far-infrared irradiation (FIR), an efficient heat treatment method, on the bioactive components of the leaves remain to be elucidated. In the present study, we investigated the effects of FIR heat treatment between 160 and 200 °C on the deglycosylation and dehydration rates of the bioactive components in American ginseng leaves. As the temperature was increased, the amounts of common ginsenosides decreased while those of rare ginsenosides increased. After FIR heat treatment of American ginseng leaves at an optimal 190 °C, the highest total polyphenolic content and kaempferol content were detected, the antioxidant activity was significantly enhanced, and the amounts of the rare ginsenosides F4, Rg6, Rh4, Rk3, Rk1, Rg3, and Rg5 were 41, 5, 37, 64, 222, 17, and 266 times higher than those in untreated leaves, respectively. Moreover, the radical scavenging rates for 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and the reducing power of the treated leaf extracts were 2.17, 1.86, and 1.77 times higher, respectively. Hence, FIR heat treatment at 190 °C is an efficient method for producing beneficial bioactive components from American ginseng leaves.

Biotransformation of American Ginseng Stems and Leaves by an Endophytic Fungus Umbelopsis sp. and Its Effect on Alzheimer's Disease Control

BACKGROUND

Common ginsenosides can be transformed into rare ginsenosides through microbial fermentation, and some rare ginsenosides can prevent Alzheimer's disease (AD). This study aimed to transform common ginsenosides into rare ginsenosides through solid-state fermentation of American ginseng stems and leaves (AGSL) by an endophytic fungus and to explore whether fermented saponin extracts prevent AD.

METHODS

The powders of AGSL were fermented in a solid state by endophytic fungus. Total saponins were extracted from fermentation products using the methanol extraction method. The types of saponins were analyzed by liquid chromatography mass spectrometry (LC/MS). The Aβ42 concentration and β-secretase activity were measured by ELISA for the prevention of AD.

RESULTS

After AGSL was fermented by an endophytic fungus NSJG, the total saponin concentration of the fermented extract G-SL was higher than the unfermented CK-SL. Rare ginsenoside Rh1 was newly produced and the yield of compound K (561.79%), Rh2 (77.48%), and F2 (40.89%) was increased in G-SL. G-SL had a higher inhibition rate on Aβ42 concentration (42.75%) and β-secretase activity (42.22%) than CK-SL, possibly because the rare ginsenoside Rh1, Rh2, F2, and compound K included in it have a strong inhibitory effect on AD.

CONCLUSION

The fermented saponin extracts of AGSL show more inhibition effects on AD and may be promising therapeutic drugs or nutrients for AD.

Optimization of Fermentation Conditions and Product Identification of a Saponin-Producing Endophytic Fungus

BACKGROUND

Some fungal endophytes isolated from P. ginseng may present a new method of obtaining saponins. This experiment aimed to optimize the total saponin yield produced through in vitro fermentation by an endophytic fungus and analyze its saponin species in the fermented extract.

METHODS

Fermentation protocols were optimized with a uniform design and verified through regression analysis to maximize the total saponin yield. The saponin types under optimal fermentation conditions were then identified and analyzed using Liquid Chromatography-Mass Spectrometry.

RESULTS

The Trametes versicolor strain NSJ105 (gene accession number: OR144428) isolated from wild ginseng could produce total saponins. The total saponin yield could be increased more than two-fold through the optimization of fermentation conditions. The concentration of the total saponins achieved by the verified protocol 105-DP was close to the predicted value. The fermentation conditions of the 105-DP protocol were as follows: potato concentration 97.3 mg/mL, glucose concentration 20.6 mg/mL, inoculum volume 2.1%, fermentation broth pH 2.1, fermentation temperature 29.2 °C, and fermentation time 6 d. It was detected and analyzed that the fermented extract of 105-DP contained the ginsenosides Rf and Rb3.

CONCLUSION

The endophytic fungus Trametes versicolor strain NSJ105 has potential application value in saponin production.

American Ginseng for the Treatment of Alzheimer's Disease: A Review

Alzheimer's disease (AD) is a prevalent degenerative condition that is increasingly affecting populations globally. American ginseng (AG) has anti-AD bioactivity, and ginsenosides, as the main active components of AG, have shown strong anti-AD effects in both in vitro and in vivo studies. It has been reported that ginsenosides can inhibit amyloid β-protein (Aβ) production and deposition, tau phosphorylation, apoptosis and cytotoxicity, as well as possess anti-oxidant and anti-inflammatory properties, thus suppressing the progression of AD. In this review, we aim to provide a comprehensive overview of the pathogenesis of AD, the potential anti-AD effects of ginsenosides found in AG, and the underlying molecular mechanisms associated with these effects. Additionally, we will discuss the potential use of AG in the treatment of AD, and how ginsenosides in AG may exert more potent anti-AD effects in vivo may be a direction for further research.

Ginseng and health outcomes: an umbrella review

Background: Ginseng consumption has been associated with various health outcomes. However, there are no review articles summarizing these reports. Methods: PubMed, Embase, the Cochrane Library of Systematic Reviews, Scopus, CNKI and Wanfang databases were searched from inception to 31 July 2022. The Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) systems were used to assess the methodological quality and quality of evidence in each meta-analysis, and the results were summarized in a narrative form. Results: Nineteen meta-analyses that met the eligibility criteria were identified from among 1,233 papers. The overall methodological quality was relatively poor, with only five studies being low-quality, and 14 critically low-quality. When compared with control treatments (mainly placebo), ginseng was beneficial for improving fatigue and physical function, sexual function, menopausal symptoms, metabolic indicators, inflammatory markers, unstable angina and respiratory diseases. Adverse events included gastrointestinal symptoms and potential bleeding; however, no serious adverse events were reported. Conclusion: This umbrella review suggests that ginseng intake has beneficial therapeutic effects for diverse diseases. However, the methodological quality of studies needs to be improved considerably. In addition, it is imperative to establish the clinical efficacy of ginseng through high-quality randomized controlled trials.

Exploring the mechanism of active components from ginseng to manage diabetes mellitus based on network pharmacology and molecular docking

A large body of literature has shown that ginseng had a role in diabetes mellitus management. Ginsenosides are the main active components of ginseng. But what ginsenosides can manage in diabetic are not systematic. The targets of these ginsenosides are still incomplete. Our aim was to identify which ginsenosides can manage diabetes mellitus through network pharmacology and molecular docking. To identify the targets of these ginsenosides. In this work, we retrieved and screened ginsenosides and corresponding diabetes mellitus targets across multiple databases. PPI networks of the genes were constructed using STRING, and the core targets were screened out through topological analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed by using the R language. Finally, molecular docking was performed after bioinformatics analysis for verification. Our research results showed that 28 ginsenosides in ginseng might be against diabetes mellitus by modulating related proteins such as VEGFA, Caspase 3, and TNF-α. Among the 28 ginsenosides, 20(R)-Protopanaxatriol, 20(R)-Protopanaxadiol, and Ginsenoside Rg1 might play a significant role. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analysis showed that the management of diabetes mellitus by ginsenosides may be related to the positive regulation of reactive oxygen metabolic processes, associated with the insulin signaling pathway, TNF signaling pathway, and AMPK signaling pathway. Molecular docking results and molecular dynamics simulation showed that most ginsenosides could stably bind to the core target, mainly hydrogen bonding and hydrophobic bond. This study suggests the management of ginseng on diabetes mellitus. We believe that our results can contribute to the systematic study of the mechanism of ginsenosides for the management of diabetes mellitus. At the same time, it can provide a theoretical basis for subsequent studies on the management of ginsenosides in diabetes mellitus.

GAS6/Axl is associated with AMPK activation and attenuates H2O2-induced oxidative stress

Oxidative stress plays a key part in cardiovascular event. Growth arrest-specific gene 6 (GAS6) is a vitamin K-dependent ligand which has been shown to exert important effects in heart. The effects of GAS6 were evaluated against hydrogen peroxide (H₂O₂) ‑induced oxidative stress injury in HL-1 cardiomyocytes. A series of experimental methods were used to analyze the effects of GAS6 on cell viability, apoptosis, oxidative stress, mitochondrial function and AMPK/ACC signaling in H₂O₂‑injured HL-1 cells. In this study, we found that H₂O₂ reduced cell viability, increased apoptotic rate and intracellular reactive oxygen species (ROS). Meanwhile, H₂O₂ decreased the protein levels of GAS6, and increased the protein level of p-AMPK/AMPK, p-ACC/ACC. Then, we observed that overexpression of GAS6 significantly reduced cell death, manifested as increased cell viability, improved oxidative stress, apoptosis and upregulated the levels of GAS6, p-Axl/Axl, Nrf2, NQO1, HO-1, Bcl-2/Bax, PGC-1α, NRF1, TFAM, p-AMPK/AMPK, and p-ACC/ACC-related protein expression in HL-1 cells and H₂O₂‑injured cardiomyocytes. To further verify the results, we successfully constructed GAS6 lentiviral vectors, and found GAS6 shRNA partially reversed the above results. These data suggest that AMPK/ACC may be a downstream effector molecule in the antioxidant action of GAS6. In summary, our findings indicate that activation GAS6/Axl-AMPK signaling protects H₂O₂‑induced oxidative stress which is accompanied by the amelioration of oxidative stress, apoptosis, and mitochondrial function.

A review for discovering bioactive minor saponins and biotransformative metabolites in Panax quinquefolius L

Panax quinquefolius L. has attracted extensive attention worldwide because of its prominent pharmacological properties on type 2 diabetes, cancers, central nervous system, and cardiovascular diseases. Ginsenosides are active phytochemicals of P. quinquefolius, which can be classified as propanaxdiol (PPD)-type, propanaxtriol (PPT)-type, oleanane-type, and ocotillol-type oligo-glycosides depending on the skeleton of aglycone. Recently, advanced analytical and isolated methods including ultra-performance liquid chromatography tandem with mass detector, preparative high-performance liquid chromatography, and high speed counter-current chromatography have been used to isolate and identify minor components in P. quinquefolius, which accelerates the clarification of the material basis. However, the poor bioavailability and undetermined bio-metabolism of most saponins have greatly hindered both the development of medicines and the identification of their real active constituents. Thus, it is essential to consider the bio-metabolism of constituents before and after absorption. In this review, we described the structures of minor ginsenosides in P. quinquefolius, including naturally occurring protype compounds and their in vivo metabolites. The preclinical and clinical pharmacological studies of the ginsenosides in the past few years were also summarized. The review will promote the reacquaint of minor saponins on the growing appreciation of their biological role in P. quinquefolius.

The Efficacy of Ginseng (Panax) on Human Prediabetes and Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Results from different clinical trials on the effects of ginseng on prediabetes and type 2 diabetes (T2DM) are still inconsistent. To fill this knowledge gap, we investigated the overall effects of ginseng supplementation on improving cardiometabolic biomarkers among these patients. A systematic literature search was conducted on PubMed/MEDLINE, Scopus, Web of Science, and Cochrane library. A random-effect model was applied to estimate the weighted mean difference and 95% CI for each outcome. Overall, 20 eligible RCTs were included. Meta-analyses revealed that ginseng supplementation significantly reduced serum concentration of FPG, TC, IL-6, and HOMA-IR values. It also increased HR and TNF-α levels. Ginseng supplementation changed HOMA-IR and HDL-C significantly based on dose and changed HOMA-IR and LDL-C significantly based on study duration in a non-linear fashion. Furthermore, meta-regression analyses indicated a linear relationship between ginseng dose and absolute changes in HDL-C. Moreover, subgroup analyses showed that ginseng supplementation changed TC and LDL-C when the supplementation dose was ≥2 g/day. Our findings suggest that ginseng supplementation may be an effective strategy for improving cardiometabolic profiles in individuals with prediabetes and T2DM.

Evaluation and Screening of Hypoglycemic Activity of Total Ginsenosides GBE-5 Fraction From Panax Ginseng Berry Based on UHPLC-MS Metabolomics

Objective

Ginseng berry (GB) was the mature fruit of medicinal and edible herb, Panax ginseng C.A. Meyer, with significant hypoglycemic effect. Ginsenoside was the main hypoglycemic active component of GB. Evaluating and screening the effective components of GB was of great significance to further develop its hypoglycemic effect.

Methods

The polar fractions of ginseng berry extract (GBE) were separated by a solvent extraction, and identified by ultra-high performance liquid chromatography-high-resolution mass spectrometry (UHPLC-MS). The insulin resistance model of HepG2 cells was established, and the hypoglycemic active fraction in GBE polar fractions were screened in vitro. Rat model of type 2 diabetes mellitus (T2DM) was established to verify the hypoglycemic effect of the GBE active fraction. The metabolomic study based on UHPLC-MS was used to analyze the differential metabolites in the serum of T2DM rats after 30 days of intervention with hypoglycemic active GBE fraction. The kyoto encyclopedia of genes and genomes (KEGG) metabolic pathway enrichment analysis was used to study the main metabolic pathways involved in the regulation of hypoglycemic active parts of GBE.

Results

It was found that GBE-5 fraction had better hypoglycemic activity than other GBE polar fractions in vitro cell hypoglycemic activity screening experiment. After 30 days of treatment, the fasting blood glucose value of T2DM rats decreased significantly by 34.75%, indicating that it had significant hypoglycemic effect. Eighteen differential metabolites enriched in KEGG metabolic pathway were screened and identified in the rat serum from T2DM vs. GBE-5 group, and the metabolic pathways mainly involved in regulation include arachidonic acid (AA) metabolism, linoleic acid (LA) metabolism, unsaturated fatty acid biosynthesis, and ferroptosis.

Conclusions

The hypoglycemic effect of GBE-5 fraction was better than that of total ginsenoside of GB. The AA metabolism, LA metabolism, unsaturated fatty acid biosynthesis, and ferroptosis were the potential metabolic pathways for GBE-5 fraction to exert hypoglycemic regulation.