Ginsenoside Re Ameliorates Brain Insulin Resistance and Cognitive Dysfunction in High Fat Diet-Induced C57BL/6 Mice

Natural Saponins on Cholesterol-Related Diseases: Treatment and Mechanism

Saponins are compounds composed of lipophilic aglycones linked to hydrophilic sugars. Natural saponins are isolated from plants and some Marine organisms. As important cholesterol-lowering drugs, natural saponins have attracted wide attention for their therapeutic potential in a variety of cholesterol-related metabolic diseases. To review the effects of natural saponins on cholesterol-related metabolic diseases, and to deepen the understanding of the cholesterol-lowering mechanism of saponins. The literature related to saponins and cholesterol-lowering diseases was collected using keywords "saponins" and "cholesterol" from PubMed, Web of Science, and Google Scholar from January 2000 to May 2024. The total number of articles related to saponins and cholesterol-lowering diseases was 240 after excluding irrelevant articles. Natural saponins can regulate cholesterol to prevent and treat a variety of diseases, such as atherosclerosis, diabetes, liver disease, hyperlipidemia, cancer, and obesity. Mechanistically, natural saponins regulate cholesterol synthesis and uptake through the AMPK/SREBP2/3-hydroxy-3-methyl-glutaryl coenzyme A reductase pathway and PCSK9/LDLR pathway, and regulate cholesterol efflux and esterification targeting Liver X receptor/ABC pathway and ACAT family. Natural saponins have broad application prospects in regulating cholesterol metabolism, for the development of more cholesterol-lowering drugs provides a new train of thought. However, it is still necessary to further explore the molecular mechanism and expand clinical trials to provide more evidence.

Recent advances in nano and micro formulations of Ginsenoside to enhance their therapeutic efficacy

BACKGROUND AND AIMS

Ginsenosides, the main component of Panax ginseng, have long been recognized for their therapeutic benefits and are thought to have neuroprotective, antidiabetic, anti-depressant, antioxidant, anti-cancer, and anti-stress properties. However, due to their low water solubility, low biomembrane permeability, gastrointestinal dysfunction, and total metabolism in the body, ginsenosides have a poor absorption profile that has hindered the therapeutic potential of these organic molecules.

METHODS

Initially, we broadly illuminated the several techniques of extraction of Ginsenosides using Panax quinquefolius and Panax ginseng. Subsequently, we focused on different delivery methods to improve the stability, permeability, and solubility of natural chemicals, which raises the bioavailability of ginsenoside. Lastly, we explained significance of a variety of nano and microscale delivery systems, including liposomes, ethosomes, transfersomes, metal/metal oxide systems, micro/nanoemulsions, polymeric micro/nanoparticles (NPs), liposomes, transfersomes, and micelles to increase the bioavailability of ginsenosides.

RESULTS

The utilization of micro/nanoscale delivery methods, such as liposome-based delivery, polymer micro/nanoparticle distribution, and micro/nanoemulsion, to increase the bioavailability of ginsenosides has recently advanced, and we have emphasized these advances in this study. Furthermore, the disadvantages of ginsenosides were also discussed, including the challenges associated with putting these delivery systems into practice in clinical settings and suggestions for further research.

CONCLUSION

In summary, ginsenosides-based administration has several benefits that make it a potentially useful substance for a range of therapeutic purposes.

Melatonin rescues pregnant female mice and their juvenile offspring from high fat diet-induced alzheimer disease neuropathy

High fat diet (HFD) is a prime factor, which contributes to the present epidemic of metabolic syndrome. Prolonged intake of HFD induces oxidative stress (OS) that in turn causes neuroinflammation, neurodegeneration, insulin resistance, amyloid burden, synaptic dysfunction and cognitive impairment hence leading to Alzheimer's disease neuropathy. Melatonin (secreted by the Pineal gland) has the potential to nullify the toxic effects of reactive oxygen species (ROS) and have been shown to ameliorate various complications induced by HFD in rodent models. This study aimed to assess the neurotherapeutic effects of melatonin on HFD-induced neuroinflammation and neurodegeneration mediated by OS in pregnant female mice and their offspring. Western blotting, immunohistochemistry and antioxidant enzyme assays were used for quantification of samples from the hippocampal region of the brain of pregnant albino mice and their offspring. Short- and long-term memory was assessed by Y-maze and Morris Water Maze tests. HFD significantly induced OS leading to AD like neuropathology in the pregnant mice and their offspring while melatonin administration simultaneously with the HFD significantly prevented this neuropathy. This study reports that melatonin exerts these effects through the stimulation of SIRT1/Nrf2/HO-1 pathway that in turn reduces the HFD-induced OS and its downstream signaling. In conclusion melatonin prevents HFD-induced multiple complications that ultimately leads to the memory dysfunction in pregnant female mice and their successive generation via activation of SIRT1/Nrf2 signaling pathway.

Ginsenoside Re Prevents Depression-like Behaviors via Inhibition of Inflammation, Oxidative Stress, and Activating BDNF/TrkB/ERK/CREB Signaling: An In Vivo and In Vitro Study

Depression is a widespread disease, with high mortality and recurrence rates. Recent studies have shown that elevated cytokine levels are implicated in the molecular mechanisms of depression. Oxidative stress contributes to the stimulation of cytokine production. Growing evidence suggests that ginsenoside Re (Gs-Re) exerts a neuroprotective effect on the hippocampus by suppressing oxidative stress and inflammation. However, the effect and mechanism of Gs-Re in the treatment of depression remain understudied. This study aimed to evaluate the neuroprotective and antidepressant-like effects of Gs-Re and the possible underlying mechanisms. In this article, the antidepressant-like effect of the Gs-Re was studied both in vitro (H2O2-induced oxidative stress in HT-22 cells) and in vivo (reserpine-induced depressive model mice). Our results indicated that, at the cellular level, Gs-Re effectively enhanced cell survival following H2O2 stimulation, inhibited the mass production of oxidative stress markers (MDA and ROS), and prevented the occurrence of apoptosis. Moreover, Gs-Re significantly reduced the levels of proinflammatory cytokines IL-1β, IL-6, and TNF-α and restored the abnormal mitochondrial membrane potential. Subsequently, Gs-Re treatment reversed reserpine-induced neuroinflammation and depressive-like behaviors in vivo and inhibited microglia overactivation. Furthermore, the alterations in the BDNF/TrkB/ERK/CREB signaling pathway induced by H2O2 or reserpine in HT-22 cells or in the mouse hippocampus were significantly reversed by Gs-Re. K252a blocked the improvement of Gs-Re on depression-like behavior and eliminated the inhibition of oxidative stress and neuroinflammation in vivo. This study suggested that Gs-Re produces neuroprotective and depressive effects by inhibiting oxidative stress and inflammation and activating the BDNF/TrkB/ERK/CREB pathway.

Inhibition of Cholesteryl Ester Transfer Protein Contributes to the Protection of Ginsenoside Re Against Isoproterenol-Induced Cardiac Hypertrophy

Background and objectives Ginsenoside Re (Re), a protopanaxatriol-type saponin extracted from ginseng, is known to have potential cardioprotective effects; however, the mechanisms of Re in improving cardiac hypertrophy have not been fully elucidated. This study aimed to investigate the therapeutic effects and underlying mechanism of Re on isoproterenol (ISO)-induced cardiac hypertrophy in vivo and in vitro. Methods Rats were intraperitoneally injected with ISO 30 mg/kg thrice daily for 14 consecutive days to induce cardiac hypertrophy, and these rats were treated with atorvastatin (ATC, 20 mg/kg) or Re (20 mg/kg or 40 mg/kg) once daily for three days in advance until the end of the experiment. Heart weight index, hematoxylin and eosin staining, and hypertrophy-related fetal gene expression were measured to evaluate the effect of Re on cardiac hypertrophy in vivo. Meanwhile, the rat H9c2 cardiomyocyte hypertrophy model was induced by ISO 10 μM for 24 hours. Cell surface area and hypertrophy-related fetal gene expression were determined to assess the effect of Re on ISO-induced cardiomyocyte hypertrophy in vitro. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in both serum and cardiomyocytes were detected by enzymatic colorimetric assays. Furthermore, we chose cholesteryl ester transfer protein (CETP) as a target to explore the influence of Re on CETP expression in vivo and in vitro through real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay. Results Intraperitoneal administration of ISO into rats resulted in increases in cross-sectional cardiomyocyte area, the ratio of heart weight to body weight, the ratio of left ventricular weight to body weight, and the ratio of right ventricular weight to body weight, as well as reactivation of fetal genes; however, treatment with Re or ATC ameliorated most of these hypertrophic responses. Similarly, Re pronouncedly alleviated ISO-induced cardiomyocyte hypertrophy, as evidenced by a decreased cell surface area and downregulation of fetal genes. Moreover, our in vivo and in vitro data revealed that Re reduced TC, TG, and LDL-C levels, and enhanced HDL-C levels. Re improved cardiac hypertrophy mainly associated with the inhibition of mRNA level and protein expression of CETP, to an extent comparable to that of the classical CETP inhibitor, anacetrapib. Conclusions Our research found that CETP inhibition contributes to the protection of Re against ISO-induced cardiac hypertrophy, which provides evidence for the application of Re for cardiovascular disease treatments.

Ginseng Berry Juice (GBJ) Regulates the Inflammation in Acute Ulcerative Mouse Models and the Major Bioactive Substances Are Ginsenosides Rb3, Rc, Rd, and Re

Panax ginseng fruit is known to have various biological effects owing to its large amount of saponins such as ginsenosides. In the present study, ginseng berry juice was confirmed to be effective against acute inflammation. Ginseng berry juice was used for analysis of active constituents, antioxidant efficacy, and in vivo inflammation. A high-performance liquid chromatography method was used for analysis of ginsenosides. In an HCl/ethanol-induced acute gastric injury model, microscopic, immunofluorescent, and immunohistochemical techniques were used for analysis of inhibition of gastric injury and mechanism study. In a mouse model of acute gastritis induced with HCl/ethanol, ginseng berry juice (GBJ, 250 mg/kg) showed similar gastric injury inhibitory effects as cabbage water extract (CB, 500 mg/kg, P.O). GBJ dose-dependently modulated the pro-inflammatory cytokines such as Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), and Interleukin-13 (IL-13). GBJ inhibited the activation of Nuclear Factor kappa bB (NF-κB) and suppressed the expressions of cyclooxigenase-2 (COX-2) and prostaglandin 2 (PGE2). The anti-inflammatory effect of GBJ is attributed to ginsenosides which have anti-inflammatory effects. Productivity as an effective food source for acute gastritis was analyzed and showed that GBJ was superior to CB. In addition, as a functional food for suppressing acute ulcerative symptoms, it was thought that the efficacy of gastric protection products would be higher if GBJ were produced in the form of juice rather than through various extraction methods.

Mechanisms with network pharmacology approach of Ginsenosides in Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory loss, cognitive disorder, language dysfunction, and mental disability. The main neuropathological changes in AD mainly include amyloid plaque deposition, neurofibrillary tangles, synapse loss, and neuron reduction. However, the current anti-AD drugs do not demonstrate a favorable effect in altering the pathological course of AD. Moreover, long-term use of these drugs is usually accompanied with various side effects. Ginsenosides are the major active constituents of ginseng and have protective effects on AD through various mechanisms in both in vivo and in vitro studies. In this review, we focused on discussing the therapeutic potential effects and the mechanisms of pharmacological activities of ginsenosides in AD, to provide new insight for further research and clinical application of ginsenosides in the future. Recent studies on the pharmacological effects and mechanisms of ginsenosides were retrieved from Chinese National Knowledge Infrastructure, National Science and Technology Library, Wanfang Data, Elsevier, ScienceDirect, PubMed, SpringerLink, and the Web of Science database up to April 2023 using relevant keywords. Network pharmacology and bioinformatics analysis were used to predict the therapeutic effects and mechanisms of ginsenosides against AD. Ginsenosides presented a wide range of therapeutic and biological activities, including alleviating Aβ deposition, decreasing tau hyperphosphorylation, regulating the cholinergic system, resisting oxidative stress, modulating Ca2+ homeostasis, as well as anti-inflammation and anti-apoptosis in neurons, respectively. For further developing the therapeutic potential as well as clinical applications, the network pharmacology approach was combined with a summary of published studies.

Characterization and Exploration of the Neuroprotective Potential of Oat-Protein-Derived Peptides in PC12 Cells and Scopolamine-Treated Zebrafish

Neurodegenerative disorders pose a substantial risk to human health, and oxidative stress, cholinergic dysfunction, and inflammation are the major contributors. The purpose of this study was to explore the neuroprotective effects of oat protein hydrolysate (OPH) and identify peptides with neuroprotective potential. This study is the first to isolate and identify OPH peptides with neuroprotective potential, including DFVADHPFLF (DF-10), HGQNFPIL (HL-8), and RDFPITWPW (RW-9), by screening via peptidomes and molecular-docking simulations. These peptides showed positive effects on the activity of antioxidant enzymes and thus reduced oxidative stress through regulation of Nrf2-keap1/HO-1 gene expression in vitro and in vivo. The peptides also significantly ameliorated scopolamine-induced cognitive impairment in the zebrafish model. This improvement was correlated with mitigation of MDA levels, AChE activity, and levels of inflammatory cytokines in the brains of zebrafish. Furthermore, these peptides significantly upregulated the mRNA expression of Bdnf, Nrf2, and Erg1 in the brains of zebrafish with neurodegenerative disorders. Collectively, oat peptides have potential for use as active components in nutraceutical applications for the prevention of neurodegenerative diseases.

Korean Red Ginseng Prevents the Deterioration of Lung and Brain Function in Chronic PM2.5-Exposed Mice by Regulating Systemic Inflammation

This study was conducted to confirm the effects of Korean red ginseng on lung and brain dysfunction in a BALB/c mice model exposed to particulate matter (PM)2.5 for 12 weeks. Learning and cognitive abilities were assessed with Y-maze, passive avoidance, and Morris water maze tests. To evaluate the ameliorating effect of red ginseng extract (RGE), the antioxidant system and mitochondrial function were investigated. The administration of RGE protected lung and brain impairment by regulating the antioxidant system and mitochondrial functions damaged by PM2.5-induced toxicity. Moreover, RGE prevented pulmonary fibrosis by regulating the transforming growth factor beta 1 (TGF-β1) pathway. RGE attenuated PM2.5-induced pulmonary and cognitive dysfunction by regulating systemic inflammation and apoptosis via the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)/c-Jun N-terminal kinases (JNK) pathway. In conclusion, RGE might be a potential material that can regulate chronic PM2.5-induced lung and brain cognitive dysfunction.

Brain targeted peptide-functionalized chitosan nanoparticles for resveratrol delivery: Impact on insulin resistance and gut microbiota in obesity-related Alzheimer's disease

The pathology of Alzheimer's disease (AD) is highly correlated with obesity-induced insulin resistance. Resveratrol (Res) is a natural phenol that demonstrates a neuroprotective effect, but the bioactivity of Res is low in vivo. Here, chitosan (CS) was cross-linked with sodium tripolyphosphate (TPP) to encapsulate low water solubility Res. Next, a brain-targeted peptide (TG: TGNYKALHPHNG) was modified on the surface of Res-loaded CS/TPP nanoparticles (TG-Res-CS/TPP-NPs) to specifically deliver Res to the brain. Morris water maze results indicated that cognitive impairments were ameliorated by TG-Res-CS/TPP-NPs in obesity-related AD mice. Obesity-related insulin resistance promotes Tau phosphorylation and Aβ aggregation in the brain. Administration of TG-Res-CS/TPP-NPs alleviated lipid deposition-induced insulin resistance and decreased the level of phosphorylated Tau and Aβ aggregation via the JNK/AKT/GSK3β pathway. Additionally, TG-Res-CS/TPP-NPs transported across blood-brain barrier which in turn increased glucose transporter expression levels, antioxidant enzyme activity and inhibited microglial cell activation. Thus, TG-Res-CS/TPP-NPs were more effective than Res-CS/TPP-NPs at regulating glucose homeostasis, oxidative stress and neuroinflammation in the brain. Moreover, inflammatory, lipid metabolism and oxidative stress-related gut microbiota including Helicobacter, Colidextribacter, Anaerotruncus, Parasutterella, Allobaculum, Alloprevotella, Alistipes, Bifidobacterium and Candidatus_Saccharimonas were also regulated by TG-Res-CS/TPP-NPs. This work indicates the potential use of TG-Res-CS/TPP-NPs for the delivery of Res.

Ginsenoside Rg1 in neurological diseases: From bench to bedside

Ginseng has been used in China as a superior medicinal material for thousands of years that can nourish the five internal organs, calm the mind and benefit wisdom. Due to its anti-inflammatory, antioxidant and neuroprotective activities, one of the active components of ginseng, ginsenoside Rg1, has been extensively investigated in the remedy of brain disorders, especially dementia and depression. In this review, we summarized the research progress on the action mechanisms of Rg1 ameliorating depression-like behaviors, including inhibition of hyperfunction of hypothalamic-pituitary-adrenal (HPA) axis, regulation of synaptic plasticity and gut flora. Rg1 may alleviate Alzheimer's disease in the early phase, as well as in the middle-late phases through repairing dendrite, axon and microglia- and astrocyte-related inflammations. We also proposed that Rg1 could regulate memory state (the imbalance of working and aversive memory) caused by distinct stimuli. These laboratory studies would further the clinical trials on Rg1. From the prospective of drug development, we discussed the limitations of the present investigations and proposed our ideas to increase permeability and bioavailability of Rg1. Taken together, Rg1 has the potential to treat neuropsychiatric disorders, but a future in-depth investigation of the mechanisms is still required. In addition, drug development will benefit from the clinical trials in one specific neuropsychiatric disorder.

Hypolipidemic effect and molecular mechanism of ginsenosides: a review based on oxidative stress

Hyperlipidemia is considered a risk factor for cardiovascular and endocrine diseases. However, effective approaches for treating this common metabolic disorder remain limited. Ginseng has traditionally been used as a natural medicine for invigorating energy or "Qi" and has been demonstrated to possess antioxidative, anti-apoptotic, and anti-inflammatory properties. A large number of studies have shown that ginsenosides, the main active ingredient of ginseng, have lipid-lowering effects. However, there remains a lack of systematic reviews detailing the molecular mechanisms by which ginsenosides reduce blood lipid levels, especially in relation to oxidative stress. For this article, research studies detailing the molecular mechanisms through which ginsenosides regulate oxidative stress and lower blood lipids in the treatment of hyperlipidemia and its related diseases (diabetes, nonalcoholic fatty liver disease, and atherosclerosis) were comprehensively reviewed. The relevant papers were search on seven literature databases. According to the studies reviewed, ginsenosides Rb1, Rb2, Rb3, Re, Rg1, Rg3, Rh2, Rh4, and F2 inhibit oxidative stress by increasing the activity of antioxidant enzymes, promoting fatty acid β-oxidation and autophagy, and regulating the intestinal flora to alleviate high blood pressure and improve the body's lipid status. These effects are related to the regulation of various signaling pathways, such as those of PPARα, Nrf2, mitogen-activated protein kinases, SIRT3/FOXO3/SOD, and AMPK/SIRT1. These findings suggest that ginseng is a natural medicine with lipid-lowering effects.

Ginsenoside and Its Therapeutic Potential for Cognitive Impairment

Cognitive impairment (CI) is one of the major clinical features of many neurodegenerative diseases. It can be aging-related or even appear in non-central nerve system (CNS) diseases. CI has a wide spectrum that ranges from the cognitive complaint with normal screening tests to mild CI and, at its end, dementia. Ginsenosides, agents extracted from a key Chinese herbal medicine (ginseng), show great promise as a new therapeutic option for treating CI. This review covered both clinical trials and preclinical studies to summarize the possible mechanisms of how ginsenosides affect CI in different diseases. It shows that ginsenosides can modulate signaling pathways associated with oxidative stress, apoptosis, inflammation, synaptic plasticity, and neurogenesis. The involved signaling pathways mainly include the PI3K/Akt, CREB/BDNF, Keap1/Nrf2 signaling, and NF-κB/NLRP3 inflammasome pathways. We hope to provide a theoretical basis for the treatment of CI for related diseases by ginsenosides.

A comprehensive system review of pharmacological effects and relative mechanisms of Ginsenoside Re: Recent advances and future perspectives

BACKGROUND

Ginsenoside Re (Re) belongs to protopanaxatriol saponins and exists in Panax ginseng, Panax quinquefolium, Panax notoginseng, and other plants in the Araliaceae family. Re has recently become a research focus owing to its pharmacological activities and benefits to human bodies.

PURPOSE

To summarize recent findings regarding the pharmacological effects and mechanisms of Re and highlight and predict the potential therapeutic effects and systematic mechanism of Re.

METHODS

Recent studies (2011-2021) on the pharmacological effects and mechanisms of Re were retrieved from Web of Science, PubMed, Google Scholar, Scopus, and Embase up to December 2021 using relevant keywords. Network pharmacology and bioinformatics analysis were used to predict the therapeutic effects and mechanisms of Re against potential diseases.

RESULTS

Re presented a wide range of therapeutic and biological activities, including neuroprotective, cardiovascular, antidepressant, antitumorigenic, and others effects. The related pharmacological mechanisms of Re include the regulation of cholinergic and antioxidant systems in the brain; the induction of tumor cell apoptosis; the inhibition of tau protein hyperphosphorylation and oxidative stress; the activation of p38MAPK, ERK1/2, and JNK signals; the improvement of lipid metabolism; and the reduction of endothelial cell dysfunction.

CONCLUSION

This paper summarizes comprehensively the current research progress of Re and provides new research insights into the therapeutic effects and mechanisms of Re against potential diseases.

Neuroprotective Effect and Possible Mechanisms of Berberine in Diabetes-Related Cognitive Impairment: A Systematic Review and Meta-Analysis of Animal Studies

Berberine, the main bioactive component of Coptis chinensis Franch., is widely used in the treatment of diabetes. Previous studies have reported that berberine supplementation may play a multitarget therapeutic role in diabetes-related cognitive impairment (DCI). This systematic review and meta-analysis evaluated the effect and possible mechanisms of berberine in animal models of DCI. Relevant studies were searched through PubMed, Web of Science, Embase, and three Chinese databases (CNKI, Wanfang, and VIP) until March 2022. Twenty studies involving 442 animals were included, and SYRCLE’s risk of bias tool was used to assess methodological quality. The statistical analysis was performed using STATA 15.0 to calculate the weighted standard mean difference (SMD) with a 95% confidence interval (CI). The fasting blood glucose (FBG) and Morris water maze test (MWM) were the main outcomes to be analyzed. The overall results showed that berberine could significantly improve FBG, escape latency, the times of crossing the platform, the time spent in the target quadrant, serum insulin, 2hBG of oral glucose tolerance test (OGTT), amyloid β (Aβ), acetylcholinesterase (AChE), oxidative stress, and inflammation levels. The present meta-analysis demonstrated that berberine could not only lower blood glucose levels but also improve learning and memory in DCI animal models, which might involve regulating glucose and lipid metabolism, improving insulin resistance, anti-oxidation, anti-neuroinflammation, inhibiting endoplasmic reticulum (ER) stress; and improving the cholinergic system. However, additional attention should be paid to these outcomes due to the significant heterogeneity.

Pharmacological Properties of Ginsenoside Re

Ginsenoside Re is a protopanaxatriol-type saponin extracted from the berry, leaf, stem, flower bud, and root of Panax ginseng. In recent years, ginsenoside Re (Re) has been attracting attention as a dietary phytochemical. In this review, studies on Re were compiled by searching a combination of keywords, namely “pharmacology,” “pharmacokinetics,” and “toxicology,” in the Google Scholar, NCBI, PubMed, and Web of Science databases. The aim of this review was to provide an exhaustive overview of the pharmacological activities, pharmacokinetics, and toxicity of Re, focusing on clinical evidence that has shown effectiveness in specific diseases, such as diabetes mellitus, nervous system diseases, inflammation, cardiovascular disease, and cancer. Re is also known to eliminate virus, enhance the immune response, improve osteoporosis, improve skin barrier function, enhance intracellular anti-oxidant actions, regulate cholesterol metabolism, alleviate allergic responses, increase sperm motility, reduce erectile dysfunction, promote cyclic growth of hair follicles, and reduce gastrointestinal motility dysfunction. Furthermore, this review provides data on pharmacokinetic parameters and toxicological factors to examine the safety profile of Re. Such data will provide a theoretical basis and reference for Re-related studies and future applications.

α-Lipoic Acid Strengthens the Antioxidant Barrier and Reduces Oxidative, Nitrosative, and Glycative Damage, as well as Inhibits Inflammation and Apoptosis in the Hypothalamus but Not in the Cerebral Cortex of Insulin-Resistant Rats

The research determined the role of α-lipoic acid (ALA) in reducing the brain manifestations of insulin resistance. The mechanism of ALA action is mainly based on its ability to “scavenge” oxygen free radicals and stimulate biosynthesis of reduced glutathione (GSH), considered the most critical brain antioxidant. Although the protective effect of ALA is widely documented in various diseases, there are still no studies assessing the influence of ALA on brain metabolism in the context of insulin resistance and type 2 diabetes. The experiment was conducted on male Wistar rats fed a high-fat diet for ten weeks with intragastric administration of ALA for four weeks. We are the first to demonstrate that ALA improves the function of enzymatic and nonenzymatic brain antioxidant systems, but the protective effects of ALA were mainly observed in the hypothalamus of insulin-resistant rats. Indeed, ALA caused a significant increase in superoxide dismutase, catalase, peroxidase, and glutathione reductase activities, as well as GSH concentration and redox potential ([GSH]²/[GSSG]) in the hypothalamus of HFD-fed rats. A consequence of antioxidant barrier enhancement by ALA is the reduction of oxidation, glycation, and nitration of brain proteins, lipids, and DNA. The protective effects of ALA result from hypothalamic activation of the transcription factor Nrf2 and inhibition of NF-κB. In the hypothalamus of insulin-resistant rats, we demonstrated reduced levels of oxidation (AOPP) and glycation (AGE) protein products, 4-hydroxynoneal, 8-isoprostanes, and 3-nitrotyrosine and, in the cerebral cortex, lower levels of 8-hydroxydeoxyguanosine and peroxynitrite. In addition, we demonstrated that ALA decreases levels of proinflammatory TNF-α but also increases the synthesis of anti-inflammatory IL-10 in the hypothalamus of insulin-resistant rats. ALA also prevents neuronal apoptosis, confirming its multidirectional effects within the brain. Interestingly, we have shown no correlation between brain and serum/plasma oxidative stress biomarkers, indicating the different nature of redox imbalance at the central and systemic levels. To summarize, ALA improves antioxidant balance and diminishes oxidative/glycative stress, protein nitrosative damage, inflammation, and apoptosis, mainly in the hypothalamus of insulin-resistant rats. Further studies are needed to determine the molecular mechanism of ALA action within the brain.

Antidiabetic Phytochemicals From Medicinal Plants: Prospective Candidates for New Drug Discovery and Development

Diabetes, a chronic physiological dysfunction affecting people of different age groups and severely impairs the harmony of peoples' normal life worldwide. Despite the availability of insulin preparations and several synthetic oral antidiabetic drugs, there is a crucial need for the discovery and development of novel antidiabetic drugs because of the development of resistance and side effects of those drugs in long-term use. On the contrary, plants or herbal sources are getting popular day by day to the scientists, researchers, and pharmaceutical companies all over the world to search for potential bioactive compound(s) for the discovery and development of targeted novel antidiabetic drugs that may control diabetes with the least unwanted effects of conventional antidiabetic drugs. In this review, we have presented the prospective candidates comprised of either isolated phytochemical(s) and/or extract(s) containing bioactive phytoconstituents which have been reported in several in vitro, in vivo, and clinical studies possessing noteworthy antidiabetic potential. The mode of actions, attributed to antidiabetic activities of the reported phytochemicals and/or plant extracts have also been described to focus on the prospective phytochemicals and phytosources for further studies in the discovery and development of novel antidiabetic therapeutics.

Ginsenosides in central nervous system diseases: Pharmacological actions, mechanisms, and therapeutics

The nervous system is one of the most complex physiological systems, and central nervous system diseases (CNSDs) are serious diseases that affect human health. Ginseng (Panax L.), the root of Panax species, are famous Chinese herbs that have been used for various diseases in China, Japan, and Korea since ancient times, and remain a popular natural medicine used worldwide in modern times. Ginsenosides are the main active components of ginseng, and increasing evidence has demonstrated that ginsenosides can prevent CNSDs, including neurodegenerative diseases, memory and cognitive impairment, cerebral ischemia injury, depression, brain glioma, multiple sclerosis, which has been confirmed in numerous studies. Therefore, this review summarizes the potential pathways by which ginsenosides affect the pathogenesis of CNSDs mainly including antioxidant effects, anti-inflammatory effects, anti-apoptotic effects, and nerve protection, which provides novel ideas for the treatment of CNSDs.

High fat diet-induced brain damaging effects through autophagy-mediated senescence, inflammation and apoptosis mitigated by ginsenoside F1-enhanced mixture

Background

Herbal medicines are popular approaches to capably prevent and treat obesity and its related diseases. Excessive exposure to dietary lipids causes oxidative stress and inflammation, which possibly induces cellular senescence and contribute the damaging effects in brain. The potential roles of selective enhanced ginsenoside in regulating high fat diet (HFD)-induced brain damage remain unknown.

Methods

The protection function of Ginsenoside F1-enhanced mixture (SGB121) was evaluated by in vivo and in vitro experiments. Human primary astrocytes and SH-SY5Y cells were treated with palmitic acid conjugated Bovine Serum Albumin, and the effects of SGB121 were determined by MTT and lipid uptake assays. For in vivo tests, C57BL/6J mice were fed with high fat diet for 3 months with or without SGB121 administration. Thereafter, immunohistochemistry, western blot, PCR and ELISA assays were conducted with brain tissues.

Results and conclusion

SGB121 selectively suppressed HFD-induced oxidative stress and cellular senescence in brain, and reduced subsequent inflammation responses manifested by abrogated secretion of IL-6, IL-1β and TNFα via NF-κB signaling pathway. Interestingly, SGB121 protects against HFD-induced damage by improving mitophagy and endoplasmic reticulum-stress associated autophagy flux and inhibiting apoptosis. In addition, SGB121 regulates lipid uptake and accumulation by FATP4 and PPARα. SGB121 significantly abates excessively phosphorylated tau protein in the cortex and GFAP activation in corpus callosum. Together, our results suggest that SGB121 is able to favor the resistance of brain to HFD-induced damage, therefore provide explicit evidence of the potential to be a functional food.

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High fat diet induces oxidative stress and subsequent cellular senescence in mice brain.

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High fat diet induces pathologies in cortex and GFAP activation in corpus callosum.

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Ginsenoside F1-enhanced mixture ameliorates damaging effect by modulating autophagy flux and inflammation.

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

American ginseng (Panax quinquefolius L.) is popularly consumed as traditional herbal medicine and health food for the treatment of type 2 diabetes mellitus (T2DM). Malonyl ginsenosides (MGR) are the main natural ginsenosides in American ginseng. However, whether the malonyl ginsenosides in P. quinquefolius (PQ-MGR) possess antidiabetic effects has not been explored yet. In this study, the antidiabetic effects and the underlying mechanism of PQ-MGR in high-fat diet/streptozotocin (HFD/STZ)-induced T2DM mice were investigated. The chemical composition was analyzed by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Our results showed that 14 malonyl ginsenosides were identified in the PQ-MGR. Among them, the content of m-Rb₁ represented about 77.4% of the total malonyl ginsenosides. After a 5-week experiment, the PQ-MGR significantly reduced the fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), nonesterified fatty acid (NEFA), alanine transaminase (ALT), and aspartate transaminase (AST) levels and improved glucose tolerance and insulin resistance. Furthermore, Western blot analysis demonstrated that the protein expressions of p-PI3K, p-AKT, p-AMPK, p-ACC, PPAR_γ, and GLUT4 in the liver and skeletal muscle were significantly upregulated after PQ-MGR treatment. In contrast, the protein expressions of p-IRS1 and p-JNK were significantly downregulated. Our results revealed that PQ-MGR could ameliorate glucose and lipid metabolism and insulin resistance in T2DM via regulation of the insulin receptor substrate-1/phosphoinositide3-kinase/protein-kinase B (IRS1/PI3K/Akt) and AMP-activated protein kinase/acetyl-CoA carboxylase (AMPK/ACC) pathways. These findings suggest that PQ-MGR may be used as an antidiabetic candidate drug for T2DM treatment.

UHPLC-MS-Based Serum and Urine Metabolomics Reveals the Anti-Diabetic Mechanism of Ginsenoside Re in Type 2 Diabetic Rats

Panax ginseng was employed in the treatment of “Xiao-Ke” symptom, which nowadays known as diabetes mellitus, in traditional Chinese medicine for more than a thousand years. Ginsenoside Re was the major pharmacologic ingredient found abundantly in ginseng. However, the anti-diabetic of Ginsenoside Re and its underlying mechanism in metabolic level are still unclear. Serum and urine metabolomic method was carried out to investigate the anti-diabetic pharmacological effects and the potential mechanism of Ginsenoside Re on high-fat diet combined streptozotocin-induced type 2 diabetes mellitus (T2DM) rats based on ultra-high-performance liquid chromatography coupled with quadrupole exactive orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap/MS). Serum and urine samples were collected from the control group (CON), T2DM group, metformin (MET) treatment group, and ginsenoside Re treatment group after intervention. The biochemical parameters of serum were firstly analyzed. The endogenous metabolites in serum and urine were detected by UHPLC-MS. The potential metabolites were screened by multivariate statistical analysis and identified by accurate mass measurement, MS/MS, and metabolite databases. The anti-diabetic-related metabolites were analyzed by KEGG metabolic pathway, and its potential mechanism was discussed. The treatment of ginsenoside Re significantly reduced the blood glucose and serum lipid level improved the oxidative stress caused by T2DM. Biochemical parameters (urea nitrogen, uric acid) showed that ginsenoside Re could improve renal function in T2DM rats. Respective 2 and 6 differential metabolites were found and identified in serum and urine of ginsenoside Re compared with T2DM group and enriched in KEGG pathway. Metabolic pathways analysis indicated that the differential metabolites related to T2DM were mainly involved in arachidonic acid metabolism, Vitamin B6, steroid hormone biosynthesis, and bile secretion metabolic pathways. This study verified the anti-diabetic and anti-oxidation effects of ginsenoside Re, elaborated that ginsenoside Re has a good regulation of the metabolic disorder in T2DM rats, which could promote insulin secretion, stimulated cannabinoid type 1 receptor (CB₁), and CaMKK β to activate AMPK signaling pathway, inhibited insulin resistance, and improved blood glucose uptake and diabetic nephropathy, so as to play the role of anti-diabetic.

The effects of ginseng on the metabolic syndrome: An updated review

Metabolic syndrome is a group of risk factors including high blood glucose, dyslipidemia, high blood pressure, and high body weight. It can increase the risk of diabetes and cardiovascular disorders, which are the important reasons for death around the world. Nowadays, there are numerous demands for herbal medicine because of less harmful effects and more useful effects in comparison with chemical options. Ginseng is one of the most famous herbs used as a drug for a variety of disorders in humans. The antihyperlipidemia, antihypertension, antihyperglycemic, and anti-obesity effects of ginseng and its active constituents such as ginsenosides have been shown in different studies. In this review article, the different in vitro, in vivo, and human studies concerning the effects of ginseng and its active constituents in metabolic syndrome have been summarized. According to these studies, ginseng can control metabolic syndrome and related diseases.

Dietary Moutan Cortex Radicis Improves Serum Antioxidant Capacity and Intestinal Immunity and Alters Colonic Microbiota in Weaned Piglets

Background:Moutan cortex radicis (MCR), as a common traditional Chinese medicine, has been widely used as an antipyretic, antiseptic, and anti-inflammatory agent in China.

Objectives: This study aimed to investigate the effects of dietary MCR supplementation on the antioxidant capacity and intestinal health of the pigs and to explore whether MCR exerts positive effects on intestinal health via regulating nuclear factor kappa-B (NF-κB) signaling pathway and intestinal microbiota.

Methods: MCR powder was identified by LC-MS analysis. Selected 32 weaned piglets (21 d of age, 6.37 ± 0.10 kg average BW) were assigned (8 pens/diet, 1 pig/pen) to 4 groups and fed with a corn-soybean basal diet supplemented with 0, 2,000, 4,000, and 8,000 mg/kg MCR for 21 d. After the piglets were sacrificed, antioxidant indices, histomorphology examination, and inflammatory signaling pathway expression were assessed. The 16s RNA sequencing was used to analyze the effects of MCR on the intestinal microbiota structure of piglets.

Results: Supplemental 4,000 mg/kg MCR significantly increased (P < 0.05) the average daily weight gain (ADG), average daily feed intake (ADFI), total antioxidative capability, colonic short-chain fatty acids (SCFA) concentrations, and the crypt depth in the jejunum but decreased (P < 0.05) the mRNA expression levels of interferon γ, tumor necrosis factor-α, interleukin-1β, inhibiting kappa-B kinase β (IKKβ), inhibiting nuclear factor kappa-B (IκBα), and NF-κB in the jejunum and ileum. Microbiota sequencing identified that MCR supplementation significantly increased the microbial richness indices (Chao1, ACE, and observed species, P < 0.05) and the relative abundances of Firmicutes and Lactobacillus (P < 0.05), decreased the relative abundances of Bacteroides, Parabacteroides, unidentified_Lachnospiraceae, and Enterococcus (P < 0.05) and had no significant effects on the diversity indices (Shannon and Simpson, P > 0.05). Microbial metabolic phenotypes analysis also showed that the richness of aerobic bacteria and facultative anaerobic bacteria, oxidative stress tolerance, and biofilm forming were significantly increased (P < 0.05), and the richness of anaerobic bacteria and pathogenic potential of gut microbiota were reduced (P < 0.05) by MCR treatment. Regression analysis showed that the optimal MCR supplemental level for growth performance, serum antioxidant capacity, and intestinal health of weaned piglets was 3,420 ~ 4,237 mg/kg.

Conclusions: MCR supplementation improved growth performance and serum antioxidant capacity, and alleviated intestinal inflammation by inhibiting the IKKβ/IκBα/NF-κB signaling pathway and affecting intestinal microbiota in weaned piglets.

Ginsenoside Re protects against chronic restraint stress-induced cognitive deficits through regulation of NLRP3 and Nrf2 pathways in mice

Exposure to chronic stress negatively affects the development of cognition, characterized by learning and memory decline. Ginsenoside Re (GRe), an active compound derived from Panax ginseng, exhibited neuroprotective activity in various neurological diseases. In this study, the protective effect of GRe on chronic restraint stress (CRS)-induced memory deficit was investigated. The mice were experienced 35 days of the CRS induction. The GRe was administered daily orally (10, 20, or 40 mg/kg) during the next 3 weeks stress session and the behavior test period. The CRS-induced memory impairment mice were subjected to behavioral tasks, such as the Y-maze, novel objects recognition, and step-through passive avoidance tests. Nissl staining was used to examine the neuron numbers. The levels of antioxidant enzymes, malondialdehyde, and proinflammatory factor were determined by kits and ELISA assays. The expressions of brain-derived neurotrophic factor (BDNF), NOD-like receptor protein 3 (NLRP3), nuclear factor erythroid-2 related factor 2 (Nrf2) and synapse-associated proteins (synaptophysin, SYP, and postsynaptic density 95, PSD95) were measured by Western blotting. Behavioral assessments indicated that GRe could ameliorate the cognitive impairment of CRS-induced mice, as indicated by increased responses in Y-maze (p < .05), novel objects recognition (p < .01), and step-through passive avoidance tests (p < .01). In addition, GRe treatment significantly decreased the neuronal loss in CRS mice in histological examination. Moreover, chronic GRe treatment significantly ameliorated the down-regulated the expressions of BDNF, Nrf2, heme oxygenase (HO)-1, SYP, and PSD95, as well as up-regulated NLRP3, the adaptor protein ASC, and Caspase-1 protein expression in the hippocampus of CRS-treated mice. Taken together, these findings suggest that GRe has a potential therapeutic effect on memory impairment in C57BL/6J mice exposed to CRS paradigm.

Characterization and Exploration of Potential Neuroprotective Peptides in Walnut (Juglans regia) Protein Hydrolysate against Cholinergic System Damage and Oxidative Stress in Scopolamine-Induced Cognitive and Memory Impairment Mice and Zebrafish

The purpose of this study was to determine the neuroprotective effect and mechanism of walnut protein hydrolysates (WPH) against memory deficits induced by scopolamine in mice and further to validate the potent neuroprotective peptides identified by integrated approaches of in silico analysis and peptidomics in scopolamine-induced zebrafish. Results showed that a remarkable amelioration on behavioral performance was observed for oral administration of WPH, and disorders of cholinergic system and oxidative stress were normalized in the brains of mice also. Unfortunately, no obvious inflammatory response and anti-inflammatory effect were observed. Additionally, WPH significantly upregulated the expressions of antioxidant defense-related protein (Nrf2) and neurotrophic-related protein (BDNF and CREB). Furthermore, 20 peptides with relatively higher abundance and PeptideRanker scores were predicted by docking to AchE and Keap1. Among them, FY and SGFDAE with the highest binding affinities, -9.8 and -8.0 kcal/mol, were considered as the promising AchE and Keap1 inhibitors, respectively. They were further validated to have neuroprotective capacity in scopolamine-induced zebrafish, indicating that peptidomics and in silico prediction might be the effective approaches to screen neuroprotective peptides.

Preclinical systematic review of ginsenoside Rg1 for cognitive impairment in Alzheimer's disease

Ginseng has been used for the treatment of aging and memory impairment for thousands of years. Several studies have found that ginsenoside Rg1, as one of the main active components of ginseng, could potentially improve cognitive function in several different animal models. A preclinical systematic review to evaluate the efficacy and mechanisms of ginsenoside Rg1 for ameliorating cognitive impairments in Alzheimer's disease is reported here. We searched six databases from their inceptions to January 2019. Thirty-two studies were selected, which included a total of 1,643 animals. According to various cognitive behavioral tests, the results of the meta-analyses showed that ginsenoside Rg1 significantly improved cognitive behavioral impairments in most Alzheimer's disease models (P < 0.05), but there were no significant effects in animals with neuronal degeneration induced by chronic stress or in SAMP8 transgenic mice. The potential mechanisms included antioxidant and anti-inflammatory effects, amelioration of Alzheimer's disease-related pathology, synapse protection, and up-regulation of nerve cells via multiple signaling pathways.

Biological and Pharmacological Characterization of Ascorbic Acid and Nicotinamide Chitosan Nanoparticles against Insulin-Resistance-Induced Cognitive Defects: A Comparative Study

High consumption of industrialized food with high fat content is generally associated with insulin resistance, which in turn causes memory impairment and cognitive decline. Nicotinamide and ascorbic acid are among the promising neuroprotective molecules; however, an appreciable therapeutic activity necessitates the administration of a large dose of either. Therefore, the study aimed to assess if loading them in chitosan nanoparticles in doses 5-10 times lower than the unencapsulated forms would achieve comparable therapeutic results. Animals were fed a high-fat-high-fructose (HFHF) diet for 75 days. The vitamins in their conventional form (100 mg/kg) and the nanoparticles under investigation (10 and 20 mg/kg) were given orally concomitantly with the diet in the last 15 days. The intake of HFHF diet for 75 days led to an insulin-resistant state, with memory impairment, which was verified behaviorally through the object recognition test. This was accompanied by significant reduction in brain insulin-like growth factor 1 (IGF-1), increased acetylcholine esterase activity, increase in the serotonin and dopamine turnover ratio, and increase in oxidative stress and 8-OHdG, indicating cellular DNA fragmentation. Cellular energy was also decreased, and immunohistochemical examination verified the high immunoreactivity in both the cortex and hippocampus of the brain. The administration of nanoparticulated nicotinamide or ascorbic acid with a 10 times lesser dose than the unencapsulated forms managed to reverse all aforementioned harmful effects, with an even lesser immunoreactivity score than the unencapsulated form. Therefore, it can be concluded that nicotinamide or ascorbic acid chitosan nanoparticles can be recommended as daily supplements for neuroprotection in patients suffering from insulin resistance after conduction of clinical investigations.

Antiobesity effects of kimchi added with Jeju citrus concentrate on high-fat diet-induced obese mice

Citrus fruits contain an abundance of nutrients, including vitamins C and B₆ and hesperidin, which attribute to its beneficial health effects. Previously, kimchi with Jeju citrus concentrate (CK) elicited anti-obesity effects in 3T3-L1 adipocytes. Here, we aimed to investigate whether CK exhibits anti-obesity effects by reducing serum and hepatic lipid concentrations and anti-obesity-associated gene expression in high-fat diet (HFD)-induced obese C57BL/6N mice. Low-dose CK (LDCK, 50 mg/kg) and high-dose CK (HDCK, 200 mg/kg) were orally administered 3 times per week over 8 weeks with HFD diet. Body weight gain, food efficiency ratio, and tissue weight were measured. Serum glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance, leptin, and adiponectin concentrations were also assessed. The effect of CK on the lipid profile and lipid accumulation was analyzed. Body and white adipose tissue masses were significantly lower in the LDCK and HDCK groups than in the HFD group. Orally administered CK significantly decreased serum lipid, fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase levels. Hepatic lipid content also decreased in the LDCK and HDCK groups. Serum leptin concentrations decreased, whereas serum adiponectin concentrations increased, confirming the anti-obesity effects of LDCK and HDCK. The decrease of hepatic vacuoles and stained lipid droplets indicated inhibition of lipid accumulation. These results support the hypothesis that CK exhibits anti-obesity effects in vivo by reducing lipid accumulation and by regulating anti-obesity-related genes.

Ginsenoside from ginseng: a promising treatment for inflammatory bowel disease

Inflammatory bowel disease (IBD) is an autoimmune disease mediated by immune disorder and termed as one of the most refractory diseases by the Word Health Organization. Its morbidity has increased steadily over the past half century worldwide. Environmental, genetic, infectious, and immune factors are integral to the pathogenesis of IBD. Commonly known as the king of herbs, ginseng has been consumed in many countries for the past 2000 years. Its active ingredient ginsenosides, as the most prominent saponins of ginseng, have a wide range of pharmacological effects. Recent studies have confirmed that the active components of Panax ginseng have anti-inflammatory and immunomodulatory effects on IBD, including regulating the balance of immune cells, inhibiting the expression of cytokines, as well as activating Toll-like receptor 4, Nuclear factor-kappa B (NF-κB), nucleotide-binding oligomerization domain-like receptor (NLRP), mitogen-activated protein kinase signaling, and so on. Accumulated evidence indicates that ginsenosides may serve as a potential novel therapeutic drug or health product additive in IBD prevention and treatment in the future.

Mori Cortex Radicis Attenuates High Fat Diet-Induced Cognitive Impairment via an IRS/Akt Signaling Pathway

Present study was conducted to investigate ameliorating effects of Mori Cortex radicis on cognitive impair and neuronal defects in HFD-induced (High Fat Diet-Induced) obese mice. To induce obesity, C57BL/6 mice were fed an HFD for 8 weeks, and then mice were fed the HFD plus Mori Cortex radicis extract (MCR) (100 or 200 mg/kg/day) for 6 weeks. Prior to sacrifice, body weights were measured, and Y-maze test and oral glucose tolerance test were performed. Serum lipid metabolic biomarkers (TG, LDL, and HDL/total cholesterol ratio) and antioxidant enzymes (glutathione, superoxide dismutase, and catalase), malondialdehyde (MDA), and acetylcholinesterase (AChE) levels were measured in brain tissues. The expressions of proteins related to insulin signaling (p-IRS, PI3K, p-Akt, and GLUT4) and neuronal protection (p-Tau, Bcl-2, and Bax) were examined. MCR suppressed weight gain, improved serum lipid metabolic biomarker and glucose tolerance, inhibited AChE levels and MDA production, and restored antioxidant enzyme levels in brain tissue. In addition, MCR induced neuronal protective effects by inhibiting p-Tau expression and increasing Bcl-2/Bax ratio, which was attributed to insulin-induced increases in the expressions p-IRS, PI3K, p-Akt, and GLUT4. These indicate MCR may reduce HFD-induced insulin dysfunction and neuronal damage and suggest MCR be considered a functional material for the prevention of T2DM-associated neuronal disease.

In vivo evaluation and atom-based 3D-QSAR studies on saponins from shells of Xanthoceras sorbifolium Bunge as anti-AD agents

A series of oleanane type of glycosides (1-19), including nine undescribed ones (1-9), were isolated and identified from Xanthoceras sorbifolium. Subsequently, an atom-based 3D-QSAR model was constructed based on results of the in vivo anti-AD evaluation of the isolates (2-3, 10-17) and nine literature-reported anti-AD oleanane type of glycosides to clarify the structure-anti-AD activity, and under the guidance of which 19 was predicted and proved to elicit a nearly equivalent in vivo anti-AD effect as xanthoceraside and donepezil that were used as positive drugs in the Y maze and Morris water maze test.

Review of Ginseng Anti-Diabetic Studies

Ginseng is one of the most valuable and commonly used Chinese medicines not only in ancient China but also worldwide. Ginsenosides, also known as saponins or triterpenoids, are thought to be responsible for the beneficial effects of ginseng. In this review, we summarize recent publications on anti-diabetic studies of ginseng extracts and ginsenosides in cells, animals, and humans. It seems that the anti-diabetic effect of ginseng is positive for type 2 diabetic patients but has no significant impact on prediabetes or healthy adults. Regulation of insulin secretion, glucose uptake, anti-oxidative stress, and anti-inflammatory pathways may be the mechanisms involved with ginseng's anti-diabetic effects. Taken together, this summary provides evidence for the anti-diabetes effects of ginseng extracts and ginsenosides as well as the underlying mechanisms of their impact on diabetes.

Association between use of oral hypoglycemic agents in Japanese patients with type 2 diabetes mellitus and risk of depression: A retrospective cohort study

Type 2 diabetes mellitus (T2DM) is a risk factor for depression. Since brain insulin resistance plays a potential role in depression, the future risk of depression in patients with T2DM may be altered depending on the class of oral hypoglycemic agent (OHA) used for T2DM therapy. The aim of the present study was to determine if specific classes of OHAs are associated with a risk for comorbid depression in T2DM. Japanese adult patients with T2DM (n = 40 214) were divided into a case group (with depression; n = 1979) and control group (without depression; n = 38 235). After adjustment for age [adjusted odds ratio (AOR) for 10 years: 1.03; 95% confidence interval (CI): 0.99-1.07; P = .1211], sex [AOR for female: 1.39; 95% CI: 1.26-1.53; P < .0001], hemoglobin A1c [AOR for 1.0%: 1.18; 95% CI: 1.11-1.26; P < .0001], duration of T2DM [AOR for 1 year: 1.00; 95% CI: 0.99-1.01; P = .4089], and history of seven medical conditions, the odds ratios for the development of depression was significantly lower for dipeptidyl peptidase-4 (DPP-4) inhibitors [AOR: 0.31; 95% CI: 0.24-0.42; P < .0001]. However, there was no significant association for the other classes of OHAs. Therefore, this study finds that there is less risk of depression associated with the use of DPP-4 inhibitors for the treatment of T2DM.

Therapeutic Mechanisms of Herbal Medicines Against Insulin Resistance: A Review

Insulin resistance is a condition in which insulin sensitivity is reduced and the insulin signaling pathway is impaired. Although often expressed as an increase in insulin concentration, the disease is characterized by a decrease in insulin action. This increased workload of the pancreas and the consequent decompensation are not only the main mechanisms for the development of type 2 diabetes (T2D), but also exacerbate the damage of metabolic diseases, including obesity, nonalcoholic fatty liver disease, polycystic ovary syndrome, metabolic syndrome, and others. Many clinical trials have suggested the potential role of herbs in the treatment of insulin resistance, although most of the clinical trials included in this review have certain flaws and bias risks in their methodological design, including the generation of randomization, the concealment of allocation, blinding, and inadequate reporting of sample size estimates. These studies involve not only the single-flavored herbs, but also herbal formulas, extracts, and active ingredients. Numerous of in vitro and in vivo studies have pointed out that the role of herbal medicine in improving insulin resistance is related to interventions in various aspects of the insulin signaling pathway. The targets involved in these studies include insulin receptor substrate, phosphatidylinositol 3-kinase, glucose transporter, AMP-activated protein kinase, glycogen synthase kinase 3, mitogen-activated protein kinases, c-Jun-N-terminal kinase, nuclear factor-kappaB, protein tyrosine phosphatase 1B, nuclear factor-E2-related factor 2, and peroxisome proliferator-activated receptors. Improved insulin sensitivity upon treatment with herbal medicine provides considerable prospects for treating insulin resistance. This article reviews studies of the target mechanisms of herbal treatments for insulin resistance.

Insulin Resistance and Oxidative Stress in the Brain: What's New?

The latest studies have indicated a strong relationship between systemic insulin resistance (IR) and higher incidence of neurodegeneration, dementia, and mild cognitive impairment. Although some of these abnormalities could be explained by chronic hyperglycaemia, hyperinsulinemia, dyslipidaemia, and/or prolonged whole-body inflammation, the key role is attributed to the neuronal redox imbalance and oxidative damage. In this mini review, we provide a schematic overview of intracellular oxidative stress and mitochondrial abnormalities in the IR brain. We highlight important correlations found so far between brain oxidative stress, ceramide generation, β-amyloid accumulation, as well as neuronal apoptosis in the IR conditions.

The memory improving effects of round scad (Decapterus maruadsi) hydrolysates on sleep deprivation-induced memory deficits in rats via antioxidant and neurotrophic pathways

Sleep deprivation negatively influences memory formation and consolidation, which leads to memory impairment associated with oxidative stress and neurotrophic pathways.

Active ginseng components in cognitive impairment: Therapeutic potential and prospects for delivery and clinical study

Cognitive impairment is a state that affects thinking, communication, understanding, and memory, and is very common in various neurological disorders. Among many factors, age-related cognitive decline is an important area in mental health research. Research to find therapeutic medications or supplements to treat cognitive deficits and maintain cognitive health has been ongoing. Ginseng and its active components may have played a role in treating chronic disorders. Numerous preclinical studies have confirmed that ginseng and its active components such as ginsenosides, gintonin, and compound K are pharmacologically efficacious in different models of and are linked to cognitive impairment. Among their several roles, they act as an anti-neuroinflammatory and help fight against oxidative stress and modulate the cholinergic signal. These roles may be involved in enhancing cognition and attenuating impairment. There have been some clinical studies on the activity of ginseng in cognitive impairment, but many ginseng species and active compounds remain to be investigated. In addition, new formulations of active ginseng components such as nanoparticles and liposomes could be used for preclinical and clinical models of cognitive impairment. Here, we discuss the therapeutic potential of active ginseng components in cognitive impairment and their chemistry and pharmacokinetics and consider prospects for their delivery and clinical study with respect to cognitive impairment.

Ginsenoside Ameliorates Cognitive Dysfunction in Type 2 Diabetic Goto-Kakizaki Rats

Background

Ginsenoside is the major bioactive component of ginseng, which has been proven to be a neuroprotective drug. The aim of this study was to evaluate the therapeutic effect of ginsenoside in a diabetic Goto-Kakizaki (GK) rat model.

Material/Methods

Twenty GK rats were randomly divided into a diabetic model (DM) group (n=10) and a ginsenoside + DM group (n=10); Wistar rats with the same age and body weight were used as the control (CON) group (n=10). Food and water intake, body weight, and blood fasting plasma glucose were measured. The Morris water maze test was used to detect learning and memory functions of the rats. Superoxide dismutase (SOD), malondialdehyde (MDA), and inflammatory cytokines (TNF-α, IL-1β, and IL-6) in the hippocampus were analyzed after ginsenoside treatment.

Results

The blood glucose, body weight, Morris correlation index, SOD, MDA, and other test results were increased in the diabetic rats. Ginsenoside ameliorated diabetic cognitive decline.

Conclusions

The possible mechanism was related to inhibiting brain oxidative/nitrosative damage and affecting the expression of the cytokines IL-1β, IL-6, and TNF-α.

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.

Tannins Enriched Fraction of Emblica officinalis Fruits Alleviates High-Salt and Cholesterol Diet-Induced Cognitive Impairment in Rats via Nrf2-ARE Pathway

Modern diets containing high quantities of salt and cholesterol have exhibited to cause a considerable effect on our health. Such diets, when consumed in the long term, have also shown to be a precursor to several disorders such as the metabolic disorder and consequently, various other diseases, including cognitive deficits. In the present study, we used a high salt and cholesterol diet (HSCD) to induce cognitive impairment in rats and also investigated the pharmacological action of tannins enriched fractions of Emblica officinalis (EOT) - a fruit that has been traditionally used for the treatment of numerous disorders for centuries. Significant alterations in MDA, GSH, TBARS, GPx, mitochondrial ATP, and mitochondrial membrane potential levels were observed in rats fed HSCD, which indicated presence of oxidative stress. Moreover, classic signs of cognitive impairment and deficits in spatial learning and memory were observed in the neurobehavioral tests. E. officinalis tannins exhibited good affinity to Nrf2 receptors in in silico studies, significantly reversed the changes in the aforementioned biomarkers of oxidative stress which were altered in the model group, as well as improved the performance of rats in Morris water maze task. Our results also reflected that EOT supplementation significantly increased the expression of Nrf2 in the CA1 region of hippocampus and cortex. Additionally, TUNEL assay indicated that EOT supplementation led to reversal of DNA fragmentation and apoptosis caused by HSCD. Immunohistochemical analysis and western blot further revealed a surge in the nuclear location of Nrf2. Through our study, we have demonstrated that cognitive impairment can be caused in rats via HSCD as a result of the oxidative stress induced by the same. Additionally, we have investigated a novel mechanism of action for EOT (which strongly suggests to be via the Nrf2-ARE pathway) and demonstrated that it has the potential to be used in the treatment of cognitive impairment.

Links Between Obesity-Induced Brain Insulin Resistance, Brain Mitochondrial Dysfunction, and Dementia

It is widely recognized that obesity and associated metabolic changes are considered a risk factor to age-associated cognitive decline. Inflammation and increased oxidative stress in peripheral areas, following obesity, are patently the major contributory factors to the degree of the severity of brain insulin resistance as well as the progression of cognitive impairment in the obese condition. Numerous studies have demonstrated that the alterations in brain mitochondria, including both functional and morphological changes, occurred following obesity. Several studies also suggested that brain mitochondrial dysfunction may be one of underlying mechanism contributing to brain insulin resistance and cognitive impairment in the obese condition. Thus, this review aimed to comprehensively summarize and discuss the current evidence from various in vitro, in vivo, and clinical studies that are associated with obesity, brain insulin resistance, brain mitochondrial dysfunction, and cognition. Contradictory findings and the mechanistic insights about the roles of obesity, brain insulin resistance, and brain mitochondrial dysfunction on cognition are also presented and discussed. In addition, the potential therapies for obese-insulin resistance are reported as the therapeutic strategies which exert the neuroprotective effects in the obese-insulin resistant condition.

New Insights into the Mechanisms of Chinese Herbal Products on Diabetes: A Focus on the "Bacteria-Mucosal Immunity-Inflammation-Diabetes" Axis

Diabetes, especially type 2, has been rapidly increasing all over the world. Although many drugs have been developed and used to treat diabetes, side effects and long-term efficacy are of great challenge. Therefore, natural health product and dietary supplements have been of increasing interest alternatively. In this regard, Chinese herbs and herbal products have been considered a rich resource of product development. Although increasing evidence has been produced from various scientific studies, the mechanisms of action are lacking. Here, we have proposed that many herbal monomers and formulae improve glucose homeostasis and diabetes through the BMID axis; B represents gut microbiota, M means mucosal immunity, I represents inflammation, and D represents diabetes. Chinese herbs have been traditionally used to treat diabetes, with minimal side and toxic effects. Here, we reviewed monomers such as berberine, ginsenoside, M. charantia extract, and curcumin and herbal formulae such as Gegen Qinlian Decoction, Danggui Liuhuang Decoction, and Huanglian Wendan Decoction. This review was intended to provide new perspectives and strategies for future diabetes research and product.

Panax ginseng and Panax quinquefolius: From pharmacology to toxicology

The use of Panax ginseng and Panax quinquefolius in traditional Chinese medicine dates back to about 5000 years ago thanks to its several beneficial and healing properties. Over the past few years, extensive preclinical and clinical evidence in the scientific literature worldwide has supported the beneficial effects of P. ginseng and P. quinquefolius in significant central nervous system, metabolic, infectious and neoplastic diseases. There has been growing research on ginseng because of its favorable pharmacokinetics, including the intestinal biotransformation which is responsible for the processing of ginsenosides - contained in the roots or extracts of ginseng - into metabolites with high pharmacological activity and how such principles act on numerous cell targets. The aim of this review is to provide a simple and extensive overview of the pharmacokinetics and pharmacodynamics of P. ginseng and P. quinquefolius, focusing on the clinical evidence which has shown particular effectiveness in specific diseases, such as dementia, diabetes mellitus, respiratory infections, and cancer. Furthermore, the review will also provide data on toxicological factors to support the favorable safety profile of these medicinal plants.