Study of the Effect of Neutral Polysaccharides from Rehmannia glutinosa on Lifespan of Caenorhabditis elegans

Historical evolution and processing mechanism of 'nine steaming and nine drying' of traditional Chinese medicine preparation

CONTEXT

Nine steaming and nine drying is a traditional Chinese medicine (TCM) processing method and it is widely used for processing tonifying herbs. Modern research reveals that the repeated steaming and drying process varies the composition and clinical efficacy of TCM.

OBJECTIVE

This paper analyzes and explores the historical evolution, research progress, development strategies, and problems encountered in the nine steaming and nine drying process so as to provide a reasonable explanation for this method.

METHODS

English and Chinese literature from 1986 to 2023 was collected from databases including Web of Science, PubMed, Elsevier, Chinese Pharmacopoeia 2020 (CP), and CNKI (Chinese). Nine steaming and nine drying, processing, TCM and pharmacological activity were used as the key words.

RESULTS

Nine steaming and nine drying has undergone thousands of years of clinical practice. Under specific processing conditions of nine steaming and nine drying, the ingredients of the TCM have significant changes, which in turn altered clinical applications.

CONCLUSIONS

This review provides sufficient evidence to prove the rationality and scientific value of nine steaming and nine drying and puts forward a development direction for future research.

Radix rehmanniae praeparata extracts ameliorate hepatic ischemia-reperfusion injury by reversing LRP1-NOTCH1-C/EBPβ axis-mediated senescence fate of LSECs

BACKGROUND

Hepatic ischemia-reperfusion injury (HIRI) is commonly observed in cases of extensive hepatic resection and involves complex mechanisms. Cell senescence has been recognized as a factor in liver injury including HIRI, where it presents as a pro-inflammatory phenotype called senescence-associated secretory phenotype (SASP). Radix Rehmanniae Praeparata (RRP) is a commonly utilized traditional Chinese medicine known for its hepatoprotective, anti-aging and antioxidant qualities. Despite its recognized benefits, the specific mechanisms by which RRP may impede the progression of HIRI through the regulation of cell senescence and the identification of the most potent anti-aging extracts from RRP remain unclear.

MATERIALS AND METHODS

Here, we first applied different chemical analysis methods to identify the RRP aqueous extract (RRPAE) and active fractions of RRP. Next, we constructed a surgically established mouse model and a hypoxia-reoxygenation (HR)-stimulated liver sinusoidal endothelial cells (LSECs) model to explore the underlying mechanism of RRP against HIRI through transcriptomics and multiple molecular biology experiments.

RESULTS

After identifying active ingredients in RRP, we observed that RRP and its factions effectively restored LSECs fenestration and improved inflammation, cellular swelling and vascular continuity in the hepatic sinusoidal region during HIRI. Transcriptomic results revealed that RRP might reverse HIRI-induced senescence through the NOTCH signaling pathway and cell categorization further showed that the senescent cell population in HIRI liver was primarily LSECs rather than other cell types. Different RRPAE, especially RRP glucoside (RRPGLY), improved LSECs senescence and suppressed the expression of pro-inflammatory SASP genes either induced by HR insult or NOTCH1 activator, which was accompanied with the inhibition of LRP1-NOTCH1-C/EBPβ pathways. Additionally, the specific inhibition of NOTCH1 by siRNA synergistically enhanced the hepatoprotective effect of RRPGLY. The ChIP-qPCR results further showed that C/EBPβ was enriched at the promoter of a representative SASP, Il-1β, in hypoxic LSECs but was significantly inhibited by RRPGLY.

CONCLUSION

Our study not only clarified the potential mechanism of RRP active extractions in alleviating HIRI, but also highlighted RRPGLY was the main component of RRP that exerted anti-aging and anti-HIRI effects, providing a fresh perspective on the use of RRP to improve HIRI.

Transcriptome profiling reveals the protective mechanism of sulfated Cyclocarya paliurus polysaccharides against oxidative damage of IEC-6 cell

Our previous studies have shown that sulfated Cyclocarya paliurus polysaccharides (SCP3) can alleviate intestinal oxidative stress (OS) damage by improving the antioxidant capacity of the intestine, but its mechanism still needs further exploration. This study aimed to reveal the possible underlying protective mechanism of SCP3 against OS damage of intestinal epithelial cells (IEC-6) based on transcriptome profiling. The results showed that SCP3 could increase the activity of superoxide dismutase and reduce the production of malondialdehyde and reactive oxygen species. In addition, the SCP3 could also alleviate the H2O2-induced high apoptosis rate and mitochondrial membrane potential decrease in IEC-6 cells. RNA-sequencing results showed that there were 2152 differentially expressed genes between the control group and the SCP3 group, and the mitogen-activated protein kinases (MAPK) and PI3K-Akt signaling pathways are the main signaling pathways that contributed to SCP3 protecting IEC-6 cells from OS damage. In summary, the SCP3 plays a role in improving intestinal cell damage by inhibiting OS, which may be closely related to the PI3K/Akt and MAPK signaling pathways. PRACTICAL APPLICATION: This study provides a theoretical basis for the practical application of Cyclocarya paliurus polysaccharides as an antioxidant ingredient in auxiliary medicines and functional foods.

Changes in Rehmanniae Radix processing and their impact on ovarian hypofunction: potential mechanisms of action

Objective

This study evaluates the research developments concerning Rehmanniae Radix in ovarian hypofunction diseases. It explores the processing methods of Rehmanniae Radix, the variations in its compounds before and after processing, the mechanism of Rehmanniae Radix and its active compounds in improving ovarian function, and the advancements in clinical applications of traditional Chinese medicine (TCM) compound that include Rehmanniae Radix.

Methods

Comprehensive literature search was conducted using databases such as China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database, National Science and Technology Library, the Pharmacopoeia of the People's Republic of China, Pubmed, and the Web of Science Database. The search utilized the following Medical Subject Headings (MeSH) and keywords: "Rehmanniae Radix," "Drying Rehmannia Root," "Rehmannia glutinosa," "Rehmanniae Radix Praeparata," "Traditional Chinese Medicine Processing," "Pharmacological Effects," "Ovarian Aging," "Diminished ovarian reserve," "Premature ovarian insufficiency," "Premature Ovarian Failure," "Ovarian hypofunction diseases".

Results

The ancient Chinese medical books document various processing techniques for Rehmanniae Radix. Contemporary research has identified changes in its compounds processing and the resultant diverse therapeutic effects. When processed into Rehmanniae Radix Praeparata, it is noted for its ability to invigorate the kidney. TCM compound containing Rehmanniae Radix is frequently used to treat ovarian hypofunction diseases, demonstrating significant clinical effectiveness. The key changes in its compounds processing include cyclic dilute ether terpene glycosides, phenylethanol glycosides, sugars, and 5-hydroxymethylfurfural. Its pharmacological action is primarily linked to the improvement of granulosa cell proliferation, antioxidative and anti-aging properties, and modulation of the immune and inflammatory microenvironment. Furthermore, Rehmanniae Radix also offers therapeutic benefits for cardiovascular and cerebrovascular diseases, osteoporosis and cognitive dysfunction caused by low estrogen levels. Thereby Rehmanniae Radix mitigates both the short-term and long-term health risks associated with ovarian hypofunction diseases.

Conclusion

Processed Rehmanniae Radix has shown potential to improve ovarian function, and its compound prescriptions have a definite effect on ovarian dysfunction diseases. Therefore Rehmanniae Radix was garnering interest for both basic and clinical research, with promising application prospects as a future therapeutic agent for ovarian hypofunction diseases. However, further studies on its toxicology and the design of standardized clinical trials are necessary to fully establish its efficacy and safety.

Preparation of Rehmanniae Radix Praeparata Polysaccharide Iron(III) Complex and Evaluation of Its Biological Activity

This study extracted and purified a polysaccharide from Rehmanniae radix praeparata (RGP) with an average molecular weight. The structural characteristics of RGP and its iron (III) complex, RGP-Fe(III), were examined for their antioxidant properties and potential in treating iron deficiency anemia (IDA). Analysis revealed that RGP comprised Man, Rha, Gal, and Xyl, with a sugar residue skeleton featuring 1→3; 1→2, 3; and 1→2, 3, 4 linkages, among others. RGP-Fe(III) had a molecular weight of 4.39×104 Da. Notably, RGP-Fe(III) exhibited superior antioxidant activity compared to RGP alone. In IDA rat models, treatment with RGP-Fe(III) led to increased weight gain, restoration of key blood parameters including hemoglobin, red blood cells, and mean hemoglobin content, elevated serum iron levels, and decreased total iron-binding capacity. Histological examination revealed no observable toxic effects of RGP-Fe(III) on the liver and spleen. These findings suggest the potential of RGP-Fe(III) as a therapeutic agent for managing IDA and highlight its promising antioxidant properties.

Anti-aging activities of neutral and acidic polysaccharides from Polygonum multiflorum Thunb in Caenorhabditis elegans

Polygonum multiflorum Thunb (PM) is used to slow the aging process. Although polysaccharides are a major constituent of PM, their anti-aging properties have not been thoroughly investigated. Therefore, this study aimed to examine the anti-aging effects of polysaccharides extracted from PM using the Caenorhabditis elegans (C. elegans) model. Two types of water-soluble heteropolysaccharides, namely a neutral polysaccharide (RPMP-N) and an acidic polysaccharide (RPMP-A), were obtained from PM. Their structures were elucidated by various methods. The effects of these polysaccharides on the lifespan, levels of antioxidants, and activities of antioxidant-related enzymes in C. elegans were also evaluated. The results showed that RPMP-A had higher GalA content compared with RPMP-N. The average molecular weights of RPMP-N and RPMP-A were 245.30 and 28.45 kDa, respectively. RPMP-N is a α-1,4-linked dextran as the main chain, and contains a small amount of branched dextran with O-6 as the branched linkage site；RPMP-A may be a complex of α-1,4-linked dextran, HG and RG-I. Treatment with RPMP-N and RPMP-A increased the mean lifespan of C. elegans, and significantly regulated oxidative stress. RPMP-A exhibited stronger anti-aging effects compared with RPMP-N. These findings suggest that RPMP-A may be a potent antioxidant and anti-aging component that can be used for developing functional food products and effective dietary supplements.

Structural characteristics and structure-activity relationship of four polysaccharides from Lycii fructus

At present, the structure-activity relationship of polysaccharides is a common and important focus in the fields of glycobiology and carbohydrate chemistry. To better understand the effect of specific polysaccharide structures on bioactive orientation, four homogeneous polysaccharides from Lycii fructus, one neutral along with three acidic polysaccharides, were purified, structurally characterized and comparatively evaluated on the antioxidative and anti-aging activities. The GC-MS-based monosaccharide composition analysis and methylation results showed that the LFPs had similar glycosyl types but varied proportions. Nuclear magnetic resonance (NMR) spectroscopy showed that LFPs consisted of arabinogalactan, rhamnogalacturonan and homogalacturonan structural domains. The results of the structure-activity relationship indicated that the antioxidative activity was positively correlated with the galacturonic acid (GalA) content, while the neutral multi-branched chains might be responsible for the anti-aging activity. This study is the first time to compare the principal structures and multiple biological activities of LFPs, which provided a reference for the industrial development and deep excavation of the health value of LFPs.

Polysaccharide extracted from cultivated Sanghuangporous vaninii spores using three-phase partitioning with enzyme/ultrasound pretreatment: Physicochemical characteristics and its biological activity in vitro

Sanghuangporous vaninii, as a valuable dietary supplement and medicinal ingredient, contains abundant bioactive polysaccharides that have health-promoting effects. In the present study, four polysaccharides (SVSPs-C, SVSPs-E, SVSPs-U, and SVSPs-E/U) were extracted for the first time from S. vaninii spores by three-phase partitioning (TPP), enzyme pretreatment before TPP (E-TPP), ultrasonic pretreatment before TPP (U-TPP), and enzyme pretreatment followed by ultrasonic before TPP (E/U-TPP) methods, respectively. Their physicochemical characteristics and in vitro pharmacological functions were determined and compared. Results showed that four TPP-based extraction methods had remarkable impacts on the extraction yield, chemical properties, monosaccharide compositions, and molecular weights (Mw) of SVSPs. Specifically, SVSPs-E/U obtained by E/U-TPP showed the highest extraction yield (25.40 %), carbohydrate content (88.50 %), and the lowest protein content (0.86 %). The four SVSPs had high-Mw (183.8-329.1 kDa) and low-Mw (23.0-156.4 kDa) fractions and mainly consisted of galactose, glucose, and mannose with different contents. In vitro bioactivities assays indicated that SVSPs-E/U possessed stronger antioxidant, hypoglycemic, hypouricemic, immunostimulatory, and antitumor activities than those of SVSPs-C, SVSPs-E, and SVSPs-U. Therefore, our results provide an efficient and promising extraction technique for bioactive polysaccharides from S. vaninii spores, as well as SVSPs had the potential to be applied in functional food, pharmaceutical, and cosmetics fields.

Progress of research into the pharmacological effect and clinical application of the traditional Chinese medicine Rehmanniae Radix

The traditional Chinese medicine (TCM) Rehmanniae Radix (RR) refers to the fresh or dried root tuber of the plant Rehmannia glutinosa Libosch of the family Scrophulariaceae. As a traditional Chinese herbal medicine (CHM), it possesses multiple effects, including analgesia, sedation, anti-inflammation, antioxidation, anti-tumor, immunomodulation, cardiovascular and cerebrovascular regulation, and nerve damage repair, and it has been widely used in clinical practice. In recent years, scientists have extensively studied the active components and pharmacological effects of RR. Active ingredients mainly include iridoid glycosides (such as catalpol and aucuboside), phenylpropanoid glycosides (such as acteoside), other saccharides, and unsaturated fatty acids. In addition, the Chinese patent medicine (CPM) and Chinese decoction related to RR have also become major research subjects for TCM practitioners; one example is the Bolus of Six Drugs, which includes Rehmannia, Lily Bulb and Rehmannia Decoction, and Siwu Decoction. This article reviews recent literature on RR; summarizes the studies on its chemical constituents, pharmacological effects, and clinical applications; and analyzes the progress and limitations of current investigations to provide reference for further exploration and development of RR.

Antioxidant characteristics of hydrolysate from low-value sea cucumber: In vitro and in vivo activities of Caenorhabditis elegans

The antioxidant activity in vitro and in vivo of Actinopyga miliaris hydrolysate (AMH) was investigated. The proportion of oligopeptides with 150-1000 Da in AMH was 65.48%. The IC50 values of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), hydroxyl radical scavenging ability, and ferric ion reducing power of AMH were 0.37, 3.43, and 24.15 mg/mL, respectively. Compared with the control group, the body length of Caenorhabditis elegans fed with 8 mg/mL AMH extended from 632.08 μm to 1009.57 μm, and the swallowing frequency and head-swing frequency increased significantly. After being fed with AMH, the lifespan of C. elegans can be prolonged even under stress conditions, primarily due to superoxide dismutase activity, catalase activity, reduced glutathione content, and total antioxidant capacity in C. elegans increased, whereas reactive oxygen species level was reduced. The results showed that AMH had in vitro and in vivo antioxidant activity, which can alleviate oxidative damage and prolong life of C. elegans.

Antioxidant potential evaluation of polysaccharides from Camellia oleifera Abel in vitro and in vivo

The extraction process, structural characterization and free radical scavenging ability of polysaccharides from Camellia oleifera have already been widely studied. However, the antioxidant activities are still lack of systematic experiments. In this study, we used Hep G2 cells and Caenorhabditis elegans to evaluate the antioxidant potential of polysaccharides that from C. oleifera flowers (P-CF), leaves (P-CL), seed cakes (P-CC) and fruit shells (P-CS). The results showed all these polysaccharides could protect cells from oxidative damage induced by t-BHP. The highest cell viabilities were 66.46 ± 1.36 % (P-CF), 55.2 ± 2.93 % (P-CL), 54.49 ± 1.29 % (P-CC) and 61.45 ± 1.67 % (P-CS), respectively. Studies have shown that four polysaccharides may protect cells from apoptosis by reducing ROS levels and maintaining MMP balance. Moreover, P-CF, P-CL, P-CC and P-CS increased the survival rate of C. elegans under thermal stress, which reduced the production of ROS by 56.1 ± 0.67 %, 59.37 ± 1.79 %, 16.63 ± 2.51 % and 27.55 ± 2.62 %, respectively. P-CF and P-CL showed stronger protective effects on C. elegans by increasing the nuclear entry rate of DAF-16 and stimulating the expression of SOD-3. Our study suggested that C. oleifera polysaccharides have the potential to develop into a natural supplement agent.

Antiaging effects of dietary supplements and natural products

Aging is an inevitable process influenced by genetics, lifestyles, and environments. With the rapid social and economic development in recent decades, the proportion of the elderly has increased rapidly worldwide, and many aging-related diseases have shown an upward trend, including nervous system diseases, cardiovascular diseases, metabolic diseases, and cancer. The rising burden of aging-related diseases has become an urgent global health challenge and requires immediate attention and solutions. Natural products have been used for a long time to treat various human diseases. The primary cellular pathways that mediate the longevity-extending effects of natural products involve nutrient-sensing pathways. Among them, the sirtuin, AMP-activated protein kinase, mammalian target of rapamycin, p53, and insulin/insulin-like growth factor-1 signaling pathways are most widely studied. Several studies have reviewed the effects of individual natural compounds on aging and aging-related diseases along with the underlying mechanisms. Natural products from food sources, such as polyphenols, saponins, alkaloids, and polysaccharides, are classified as antiaging compounds that promote health and prolong life via various mechanisms. In this article, we have reviewed several recently identified natural products with potential antiaging properties and have highlighted their cellular and molecular mechanisms. The discovery and use of dietary supplements and natural products that can prevent and treat multiple aging-related diseases in humans will be beneficial. Thus, this review provides theoretical background for existing dietary supplements and natural products as potential antiaging agents.

Advances in Plant Polysaccharides as Antiaging Agents: Effects and Signaling Mechanisms

Aging refers to the gradual physiological changes that occur in an organism after reaching adulthood, resulting in senescence and a decline in biological functions, ultimately leading to death. Epidemiological evidence shows that aging is a driving factor in the developing of various diseases, including cardiovascular diseases, neurodegenerative diseases, immune system disorders, cancer, and chronic low-grade inflammation. Natural plant polysaccharides have emerged as crucial food components in delaying the aging process. Therefore, it is essential to continuously investigate plant polysaccharides as potential sources of new pharmaceuticals for aging. Modern pharmacological research indicates that plant polysaccharides can exert antiaging effects by scavenging free radicals, increasing telomerase activity, regulating apoptosis, enhancing immunity, inhibiting glycosylation, improving mitochondrial dysfunction regulating gene expression, activating autophagy, and modulating gut microbiota. Moreover, the antiaging activity of plant polysaccharides is mediated by one or more signaling pathways, including IIS, mTOR, Nrf2, NF-κB, Sirtuin, p53, MAPK, and UPR signaling pathways. This review summarizes the antiaging properties of plant polysaccharides and signaling pathways participating in the polysaccharide-regulating aging process. Finally, we discuss the structure-activity relationships of antiaging polysaccharides.

Extraction, structure and bioactivities of polysaccharides from Rehmannia glutinosa: A review

ETHNOPHARMACOLOGIC RELEVANCE

Rehmannia glutinosa (Gaertn.) DC. (RG) is a widely used herb for clearing heat and cooling the blood. Polysaccharides from Rehmannia glutinosa (Gaertn.) DC. (RGPs) have a variety of biological activities, including antioxidation, hypoglycemia, immune enhancement, hematopoiesis promotion, and antianxiety.

AIM OF THE STUDY

This review provides up-to-date and comprehensive information on the extraction and separation methods, structural characteristics, and pharmacological activities of RGPs. A more in-depth study on the structure and clinical pharmacology of the RGPs was investigated. To further explore the pharmacological effects of RGPS, and lay a foundation for the safe clinical application and expansion of application scope.

MATERIALS AND METHODS

Use Google Scholar, Scifinder, PubMed, Springer, Elsevier, Wiley, Web of Science and other online database search to collect the literature on extraction, separation, structural analysis and pharmacological activity of RGPs published before December 2022. The key words are "extraction", "isolation", "purification" and "pharmacological action" and "Rehmanniae polysaccharide".

RESULTS

Rehmannia glutinosa has been widely used in the treatment of diabetes since ancient times, and is known as one of the "Four Sacred Medicines" for the treatment of diabetes, along with Ginseng, Psidium Guajava and Pueraria Mirifica. The active ingredients of Rehmannia glutinosa that have been studied more in the treatment of diabetes are Rehmannia glutinosa polysaccharide and Rehmannia glutinosa oligosaccharide. The content of polysaccharides varies due to different extraction methods, and separation and purification methods. RGPs have a wide range of pharmacological activities, including antitumor, immunomodulatory, neuroprotective effect, hypoglycemic activity, cardioprotective and antioxidant activities. These pharmacological properties lay a foundation for the treatment of tumors, inflammation, hyperglycemia, myocardial ischemia, oxidative stress and other diseases with RGPs.

CONCLUSION

Based on its effects of promoting hematopoiesis, antitumor and enhancing immunity, RGPs have been clinically applied in the treatment of chronic aplastic anemia and esophageal cancer, but other effects of RGPs have not been reflected in the clinical practice. In the future, more in-depth research can be conducted on the molecular structure analysis, toxicity, side effects and clinical pharmacological effects of RGPs to further explore the pharmacological effects of RGPs and to lay the foundation for safe clinical application and expansion of application scope.

Polygonati Rhizoma Polysaccharide Prolongs Lifespan and Healthspan in Caenorhabditis elegans

Polygonati Rhizoma is the dried rhizome of Polygonatum kingianum coll.et hemsl., Polygonatum sibiricum Red. or Polygonatum cyrtonema Hua, and has a long history of medication. Raw Polygonati Rhizoma (RPR) numbs the tongue and stings the throat, while prepared Polygonati Rhizoma (PPR) can remove the numbness of the tongue, and at the same time enhance its functions of invigorating the spleen, moistening the lungs and tonifying the kidneys. There are many active ingredients in Polygonati Rhizoma (PR), among which polysaccharide is one of the most important active ingredients. Therefore, we studied the effect of Polygonati Rhizoma polysaccharide (PRP) on the lifespan of Caenorhabditis elegans (C. elegans) and found that polysaccharide in PPR (PPRP) was more effective than Polysaccharide in RPR (RPRP) in prolonging the lifespan of C. elegans, reducing the accumulation of lipofuscin, and increasing the frequency of pharyngeal pumping and movement. The further mechanism study found that PRP can improve the anti-oxidative stress ability of C. elegans, reduce the accumulation of reactive oxygen species (ROS) in C. elegans, and improve the activity of antioxidant enzymes. The results of quantitative real-time PCR(q-PCR) experiments suggested that PRP may prolong the lifespan of C. elegans by down-regulating daf-2 and activating daf-16 and sod-3, and the transgenic nematode experiments were consistent with its results, so it was hypothesized that the mechanism of age delaying effect of PRP was related to daf-2, daf-16 and sod-3 of the insulin signaling pathway. In short, our research results provide a new idea for the application and development of PRP.

Effect of fermentation modification on the physicochemical characteristics and anti-aging related activities of Polygonatum kingianum polysaccharides

In order to fully investigate the anti-aging value of the plants polysaccharides, the fermentation method was applied to modify the Polygonatum kingianum polysaccharides (PKPS), and the ultra-filtration was used to further segment the hydrolyzed polysaccharides. It was found that the fermentation induced an increase in the in vitro anti-aging-related activities of PKPS including antioxidant, hypoglycemic and hypolipidemic activity, and cellular aging-delaying ability. In particular, the low Mw fraction PS2-4 (10-50 kDa) separated from the fermented polysaccharide exhibited superior anti-aging activity on experimental animals. PS2-4 extended the Caenorhabditis elegans lifespan by 20.70 %, with an increased effect of 10.09 % compared to the original polysaccharide; it was also more effective than the original one in improving movement ability and reducing lipofuscin accumulation of worms. This fraction was screened as the optimal anti-aging active polysaccharide. After fermentation, the main molecular weight distribution of PKPS changed from 50-650 kDa to 2-100 kDa, and the chemical composition and monosaccharide composition also changed; the initial rough and porous microtopography turned into smooth state. These alterations in physicochemical characteristics suggest that fermentation exerted an influence on the structure of PKPS, which contributed to the enhanced anti-aging activity, indicating that fermentation was promising in the structural modification of polysaccharides.

The Role and Mechanism of Polysaccharides in Anti-Aging

The elderly proportion of the population is gradually increasing, which poses a great burden to society, the economy, and the medical field. Aging is a physiological process involving multiple organs and numerous reactions, and therefore it is not easily explained or defined. At present, a growing number of studies are focused on the mechanisms of aging and potential strategies to delay aging. Some clinical drugs have been demonstrated to have anti-aging effects; however, many still have deficits with respect to safety and long-term use. Polysaccharides are natural and efficient biological macromolecules that act as antioxidants, anti-inflammatories, and immune regulators. Not surprisingly, these molecules have recently gained attention for their potential use in anti-aging therapies. In fact, multiple polysaccharides have been found to have excellent anti-aging effects in different animal models including Caenorhabditis elegans, Drosophila melanogaster, and mice. The anti-aging qualities of polysaccharides have been linked to several mechanisms, such as improved antioxidant capacity, regulation of age-related gene expression, and improved immune function. Here, we summarize the current findings from research related to anti-aging polysaccharides based on various models, with a focus on the main anti-aging mechanisms of oxidative damage, age-related genes and pathways, immune modulation, and telomere attrition. This review aims to provide a reference for further research on anti-aging polysaccharides.

Preparation of Dendrobium officinale Flower Anthocyanin and Extended Lifespan in Caenorhabditis elegans

The Dendrobium officinale flower is a non-medicinal part of the plant, rich in a variety of nutrients and bioactive ingredients. The purpose of this article was to explore the preparation conditions of anthocyanins (ACNs) from the D. officinale flower. Subsequently, its anti-aging effects were evaluated with Caenorhabditis elegans. Results showed that the ACNs had antioxidant activities on scavenging free radicals (DPPH· and ABTS⁺·), and the clearance rate was positively correlated with the dose. Additionally, ACNs significantly increased the activity of superoxide dismutase (SOD) in C. elegans, which was 2.068-fold higher than that of the control. Treatment with ACNs at 150 μL extended the lifespan of C. elegans by 56.25%, and treatment with ACNs at 50 μL promoted fecundity in C. elegans. Finally, the protective effect of ACNs enhanced stress resistance, thereby increasing the survival numbers of C. elegans, which provided insights for the development and practical application of functional products.

Antioxidant Baccharis trimera Leaf Extract Suppresses Lipid Accumulation in C. elegans Dependent on Transcription Factor NHR-49

Obesity is a global public health problem that is associated with oxidative stress. One of the strategies for the treatment of obesity is the use of drugs; however, these are expensive and have numerous side effects. Therefore, the search for new alternatives is necessary. Baccharis trimera is used in Brazilian folk medicine for the treatment of obesity. Here, B. trimera leaf extract (BT) showed antioxidant activity in seven in vitro tests, and it was not toxic to 3T3 murine fibroblasts or Caenorhabditis elegans. Furthermore, BT reduces the intracellular amount of reactive oxygen species and increases C. elegans survival. Moreover, these effects were not dependent on transcription factors. The inhibition of fat accumulation by BT in the C. elegans model was also investigated. BT reduced lipid accumulation in animals fed diets without or with high amount of glucose. Furthermore, it was observed using RNA interference (iRNA) that BT depends on the transcription factor NHR-49 to exert its effect. Phytochemical analysis of BT revealed rutin, hyperoside, and 5-caffeoylquinic acid as the main BT components. Thus, these data demonstrate that BT has antioxidant and anti-obesity effects. However, further studies should be conducted to understand the mechanisms involved in its action.

Antiaging Effects of Dietary Polysaccharides: Advance and Mechanisms

Aging is a process in which the various physiological functions of the body gradually deteriorate and eventually lead to death. During this process, the body’s resistance to external stresses gradually decreases and the aging-related diseases gradually are increased. Polysaccharides are a group of active substances extracted from living organisms and are widely found in plants, animals, and microorganisms. In the last decade, a variety of natural polysaccharides from functional and medicinal foods have attracted considerable interest for their beneficial effects in the prevention of chronic diseases such as cancers, diabetes, and neurodegenerative diseases. Interestingly, these polysaccharides have also been found to delay aging by reducing oxidative damage, inhibiting telomere shortening, and being anti-inflammatory in different animal models of aging. These reviews summarized the progresses in effects of polysaccharides on antiaging and the potential mechanisms and especially focused on the signaling pathways involved in the antiaging functions. Finally, the applications and prospects of the antiaging effects of polysaccharides are discussed.

Neuroprotective Effects of Oligosaccharides in Rehmanniae Radix on Transgenic Caenorhabditis elegans Models for Alzheimer’s Disease

Rehmanniae Radix (RR, the dried tuberous roots of Rehmannia glutinosa (Gaertn.) DC.) is an important traditional Chinese medicine distributed in Henan, Hebei, Inner Mongolia, and Northeast in China. RR is frequently used to treat diabetes mellitus, cardiovascular disease, osteoporosis and aging-related diseases in a class of prescriptions. The oligosaccharides and catalpol in RR have been confirmed to have neuroprotective effects. However, there are few studies on the anti-Alzheimer’s disease (AD) effect of oligosaccharides in Rehmanniae Radix (ORR). The chemical components and pharmacological effects of dried Rehmannia Radix (DRR) and prepared Rehmannia Radix (PRR) are different because of the different processing methods. ORR has neuroprotective potential, such as improving learning and memory in rats. Therefore, this study aimed to prove the importance of oligosaccharides in DRR (ODRR) and PRR (OPRR) for AD based on the Caenorhabditis elegans (C. elegans) model and the different roles of ODRR and OPRR in the treatment of AD. In this study, we used paralysis assays, lifespan and stress resistance assays, bacterial growth curve, developmental and behavioral parameters, and ability of learning and memory to explore the effects of ODRR and OPRR on anti-AD and anti-aging. Furthermore, the accumulation of reactive oxygen species (ROS); deposition of Aβ; and expression of amy-1, sir-2.1, daf-16, sod-3, skn-1, and hsp-16.2 were analyzed to confirm the efficacy of ODRR and OPRR. OPRR was more effective than ODRR in delaying the paralysis, improving learning ability, and prolonging the lifespan of C. elegans. Further mechanism studies showed that the accumulation of ROS, aggregation, and toxicity of Aβ were reduced, suggesting that ORR alleviated Aβ-induced toxicity, in part, through antioxidant activity and Aβ aggregation inhibiting. The expression of amy-1 was downregulated, and sir-2.1, daf-16, sod-3, and hsp-16.2 were upregulated. Thus, ORR could have a possible therapeutic effect on AD by modulating the expression of amy-1, sir-2.1, daf-16, sod-3, and hsp-16.2. Furthermore, ORR promoted the nuclear localization of daf-16 and further increased the expression of sod-3 and hsp-16.2, which significantly contributed to inhibiting the Aβ toxicity and enhancing oxidative stress resistance. In summary, the study provided a new idea for the development of ORR.

Antiaging agents: safe interventions to slow aging and healthy life span extension

Human longevity has increased dramatically during the past century. More than 20% of the 9 billion population of the world will exceed the age of 60 in 2050. Since the last three decades, some interventions and many preclinical studies have been found to show slowing aging and increasing the healthy lifespan of organisms from yeast, flies, rodents to nonhuman primates. The interventions are classified into two groups: lifestyle modifications and pharmacological/genetic manipulations. Some genetic pathways have been characterized to have a specific role in controlling aging and lifespan. Thus, all genes in the pathways are potential antiaging targets. Currently, many antiaging compounds target the calorie-restriction mimetic, autophagy induction, and putative enhancement of cell regeneration, epigenetic modulation of gene activity such as inhibition of histone deacetylases and DNA methyltransferases, are under development. It appears evident that the exploration of new targets for these antiaging agents based on biogerontological research provides an incredible opportunity for the healthcare and pharmaceutical industries. The present review focus on the properties of slow aging and healthy life span extension of natural products from various biological resources, endogenous substances, drugs, and synthetic compounds, as well as the mechanisms of targets for antiaging evaluation. These bioactive compounds that could benefit healthy aging and the potential role of life span extension are discussed.

A systematic review on botany, processing, application, phytochemistry and pharmacological action of Radix Rehmnniae

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Rehmanniae (RR) is the tuber root of Rehmannia glutionsa Libosch, which was firstly recorded in Shennong's Classic of Materia Medica (⟪⟫). RR is a non-toxic and wide used traditional Chinese medicine. RR has the effect of clearing heat, generating essence, cooling blood, stopping bleeding, nourishing yin and blood, and filling marrow. It is used in clinic in the form of processed decoction pieces, including Dry Radix Rehmnniae (DRR) and Rehmanniae Radix Praeparata (RRP). The application of RR in traditional Chinese medicine (TCM) prescriptions can treat various diseases, such as anemia, irregular menstruation, deficiency of liver yin, renal failure and so on.

AIM OF REVIEW

This paper aims to provide a comprehensive and productive review of RR, which mainly contains botanical characteristics, processing methods, traditional application, chemical composition, quality control and pharmacological action.

MATERIALS AND METHODS

Literature search was conducted through the Web of Science, Baidu Scholar, ScienceDirect, PubMed, CNKI, and WanFang DATA using the keywords "Radix Rehmnniae", "Rehmanniae Radix Praeparata", "processing", "clinical application", "chemical composition", "quality control", and "pharmacological action". In addition, information was collected from relevant textbooks, reviews, and documents.

RESULTS

RR is a traditional Chinese herbal medicine with clinical value and rich resources. More than 100 components have been isolated and identified from RR. It has multiple pharmacological actions, such as hemostasis, antioxidation, anti-osteoporosis, lowering blood sugar, improving renal function, anti-inflammation, protecting neuronal function, antidepression and anti-anxiety. DRR and RRP are two different processed products of RR. After processing, there are great changes in property, taste, efficacy, clinical application, chemical composition and pharmacological action. At present, identifying chemical constituents of RR and its medicinal value has been deeply studied. However, there is a lack of research on the reasons for the differences in pharmacological effects between DRR and RRP. The reasons for these differences need to be further verified. Catalpol, the active component of RR, has been studied extensively in the literature, but the pharmacological effects of catalpol cannot represent the pharmacological effects of the whole RR. In the future, effective components such as rehmannioside D, polysaccharide, total glycosides, and effective parts in RR need to be further studied and developed. The pharmacodynamic material basis and mechanism of RR need to be further discussed. The scientific connotation and processing methods of RRP need to be studied and standardized.

Non-neglectable therapeutic options for age-related macular degeneration: A promising perspective from traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Age-related macular degeneration (AMD) is a chronic neurodegenerative disease which causes irreversible central vision loss among the elderly population. Traditional Chinese Medicine (TCM), including formulas, acupuncture and herbs, has been used in the treatment of AMD for thousands of years and is currently used by many AMD patients around the world.

AIM OF THE REVIEW

A comprehensive, in-depth literature review examining the use of TCM in the treatment of AMD has yet to be compiled. This review will improve current knowledge relating to the use of TCM and will open new avenues of exploration in developing new drugs for the treatment of AMD.

METHODS

A literature search of the PubMed database, Web of Science, Google Scholar and China National Knowledge Infrastructure (CNKI) was performed using relevant terms and keywords related to TCM in the treatment of AMD. Related books, PhD and master's theses were also researched.

RESULTS

The TCM-based interpretation of AMD has been used to establish a theoretical foundation for understanding the effect of TCM formulas and acupuncture on AMD. The possible mechanism of action of common Chinese herbs has also been discussed in detail.

CONCLUSION

TCM is a promising treatment option of AMD patients. However, lack of rigorous scientific evidence has limited the impact and uptake of TCM therapy. Future research should focus on improving understanding of the mechanism of action and bioactive components of TCM therapies.

Curcumin Acetylsalicylate Extends the Lifespan of Caenorhabditis elegans

Aspirin and curcumin have been reported to be beneficial to anti-aging in a variety of biological models. Here, we synthesized a novel compound, curcumin acetylsalicylate (CA), by combining aspirin and curcumin. We characterized how CA affects the lifespan of Caenorhabditis elegans (C. elegans) worms. Our results demonstrated that CA extended the lifespan of worms in a dose-dependent manner and reached its highest anti-aging effect at the concentration of 20 μM. In addition, CA reduced the deposition of lipofuscin or "age pigment" without affecting the reproductivity of worms. CA also caused a rightward shift of C. elegans lifespan curves in the presence of paraquat-induced (5 mM) oxidative stress or 37 °C acute heat shock. Additionally, CA treatment decreased the reactive oxygen species (ROS) level in C. elegans and increased the expression of downstream genes superoxide dismutase (sod)-3, glutathione S-transferase (gst)-4, heat shock protein (hsp)-16.2, and catalase-1 (ctl-1). Notably, CA treatment resulted in nuclear translocation of the DAF-16 transcription factor, which is known to stimulate the expression of SOD-3, GST-4, HSP-16, and CTL-1. CA did not produce a longevity effect in daf-16 mutants. In sum, our data indicate that CA delayed the aging of C. elegans without affecting reproductivity, and this effect may be mediated by its activation of DAF-16 and subsequent expression of antioxidative genes, such as sod-3 and gst-4. Our study suggests that novel anti-aging drugs may be developed by combining two individual drugs.

Prebiotic, Antioxidant, and Immunomodulatory Properties of Acidic Exopolysaccharide From Marine Rhodotorula RY1801

In this study, an extracellular acidic polysaccharide (EAPS) from marine Rhodotorula sp. RY1801 was extracted, and its biological properties were investigated. EAPS is mainly composed of monosaccharides, including mannose, rhamnose, glucose, galactose, and fucose, had an average molecular weight of 5.902 × 107 Da. The results indicated that EAPS can promote the growth of Lactobacillus acidophilus and L. acidophilus plantarum. EAPS is capable of scavenging both superoxide anion and hydroxyl radicals in vitro. The highest scavenging rate of superoxide anion and hydroxyl radicals is 29 and 84%, respectively. Using in vivo model, we found that the EAPS can expand the lifespan and increase the disease resistance of Caenorhabditis elegans against Klebsiella pneumoniae infection via the DAF-2/DAF-16 pathway. These results suggested that EAPS from marine Rhodotorula sp. RY1801 could promote the growth of beneficial bacteria and can be used as an antioxidant and immunomodulator, which had considerable potential in the food and health industry.

De novo genome assembly of the potent medicinal plant Rehmannia glutinosa using nanopore technology

Rehmannia glutinosa is a potent medicinal plant with a significant importance in traditional Chinese medicine. Its root is enriched with various bioactive molecules mainly iridoids, possessing important pharmaceutical properties. However, the molecular biology and evolution of R. glutinosa have been largely unexplored. Here, we report a reference genome of R. glutinosa using Nanopore technology, Illumina and Hi-C sequencing. The assembly genome is 2.49 Gb long with a scaffold N50 length of 70 Mb and high heterozygosity (2%). Since R. glutinosa is an autotetraploid (4n = 56), the difference between each set of chromosomes is very small, and it is difficult to distinguish the two sets of chromosomes using Hi-C. Hence, only one set of the genome size was mounted to the chromosome level. Scaffolds covering 52.61% of the assembled genome were anchored on 14 pseudochromosomes. Over 67% of the genome consists of repetitive sequences dominated by Copia long terminal repeats and 48,475 protein-coding genes were predicted. Phylogenetic analysis corroborates the placement of R. glutinosa in the Orobanchaceae family. Our results indicated an independent and very recent whole genome duplication event that occurred 3.64 million year ago in the R. glutinosa lineage. Comparative genomics analysis demonstrated expansion of the UDP-dependent glycosyltransferases and terpene synthase gene families, known to be involved in terpenoid biosynthesis and diversification. Furthermore, the molecular biosynthetic pathway of iridoids has been clarified in this work. Collectively, the generated reference genome of R. glutinosa will facilitate discovery and development of important pharmacological compounds.

A combined quality evaluation method that integrates chemical constituents, appearance traits and origins of raw Rehmanniae Radix pieces

The quality control of Chinese herbal medicine is a current challenge for the internationalization of traditional Chinese medicine. Traditional quality evaluation methods lack quantitative analysis, while modern quality evaluation methods ignore the origins and appearance traits. Therefore, an integrated quality evaluation method is urgent in need. Raw Rehmanniae Radix (RRR) is commonly used in Chinese herbal medicine. At present, much attention has been drwan towards its quality control, which however is limited by the existing quality evaluation methods. The present study was designed to establish a comprehensive and practical method for the quality evaluation and control of RRR pieces based on its chemical constituents, appearance traits and origins. Thirty-three batches of RRR pieces were collected from six provinces, while high-performance liquid chromatography (HPLC) was applied to determine the following five constituents, including catalpol, rehmannioside A, rehmannioside D, leonuride and verbascoside in RRR pieces. Their appearance traits were quantitatively observed. Furthermore, correlation analysis, principal components analysis (PCA), cluster analysis and t-test were performed to evaluate the qualities of RRR pieces. These batches of RRR pieces were divided into three categories: samples from Henan province, samples from Shandong and Shanxi provinces, and those from other provinces. Furthermore, the chemical constituents and appearance traits of RRR pieces were significantly different from diverse origins. The combined method of chemical contituents, appearance traits and origins can distinguish RRR pieces with different qualities, which provides basic reference for the quality control of Chinese herbal medicine.

A Systematic Review of Antiaging Effects of 23 Traditional Chinese Medicines

BACKGROUND

Aging is an inevitable stage of body development. At the same time, aging is a major cause of cancer, cardiovascular disease, and neurodegenerative diseases. Chinese herbal medicine is a natural substance that can effectively delay aging and is expected to be developed as antiaging drugs in the future. Aim of the review. This paper reviews the antiaging effects of 23 traditional Chinese herbal medicines or their active components. Materials and methods. We reviewed the literature published in the last five years on Chinese herbal medicines or their active ingredients and their antiaging role obtained through the following databases: PubMed, EMBASE, Scopus, and Web of Science.

RESULTS

A total of 2485 papers were found, and 212 papers were screened after removing the duplicates and reading the titles. Twenty-three studies met the requirements of this review and were included. Among these studies, 13 articles used Caenorhabditis elegans as the animal model, and 10 articles used other animal models or cell lines.

CONCLUSION

Chinese herbal medicines or their active components play an antiaging role by regulating genes related to aging through a variety of signaling pathways. Chinese herbal medicines are expected to be developed as antiaging drugs or used in the medical cosmetology industry.

In Vitro and In Vivo Antioxidant Activity of Agave sisalana Agro-Industrial Residue

Agave sisalana agro-industrial residue has considerable potential against damage associated with oxidative stress and skin aging. This study aims to demonstrate, in vitro and in vivo, the potential of Agave sisalana agro-industrial residue as a safe and effective alternative for the prevention of damage caused by oxidative stress and aging. The antioxidant activity was evaluated in vitro (total antioxidant capacity, reducing power, DPPH radical scavenging, metal chelating (Fe²⁺ and Cu²⁺), and hydroxyl radical scavenging) and in vivo using the Caenorhabditis elegans organism model. The extract showed in vitro antioxidant activity in all tests performed. Tests with C. elegans showed that the extract was able to reduce the intracellular levels of reactive oxygen species (ROS) and increase the survival rate of worms. A downregulation of gst-4::GFP expression suggests a direct action against free radicals. Agave sisalana agro-industrial residue extract (AsRE) can therefore be considered as a source of antioxidant biomolecules, and the use of this agro-industrial residue in a new production process can lead to sustainability and socioeconomic development.

Phytochemical Profiles and Antioxidant Activity of Rehmannia glutinosa from Different Production Locations

The chemical components and antioxidant activity of 16 Rehmannia glutinosa samples were investigated to reveal the high-quality raw resource for pharmaceutical products. 22 main chemical components were detected with significant content differences (P<0.05). The contents of 14 substances reached the maximum in S1 sample such as catalpol (6.74 mg g^-1 ), rehmaionoside A (1.93 mg g^-1 ) and rehmannioside D (5.13 mg g^-1 ). However, the content distribution of the other eight substances had no obvious change regulation. Three antioxidant evaluation methods commonly showed that S1 sample had strong antioxidant activity with a low IC₅₀ value of 0.022 mg mL^-1 , a high ABTS value of 524.196 μmol equiv. Trolox g^-1 , and a high FRAP value of 200.517 μmol equiv. Trolox g^-1 . Considered the medicinal value, S1 had high quality based on the present phytochemical profiles and antioxidant activity. These results also indicated that the root extracts of R. glutinosa could become useful supplement for pharmaceutical products as new antioxidant agents.

Plant and fungal products that extend lifespan in Caenorhabditis elegans

The nematode Caenorhabditis elegans is a useful model to study aging due to its short lifespan, ease of manipulation, and available genetic tools. Several molecules and extracts derived from plants and fungi extend the lifespan of C. elegans by modulating aging-related pathways that are conserved in more complex organisms. Modulation of aging pathways leads to activation of autophagy, mitochondrial biogenesis and expression of antioxidant and detoxifying enzymes in a manner similar to caloric restriction. Low and moderate concentrations of plant and fungal molecules usually extend lifespan, while high concentrations are detrimental, consistent with a lifespan-modulating mechanism involving hormesis. We review here molecules and extracts derived from plants and fungi that extend the lifespan of C. elegans, and explore the possibility that these natural substances may produce health benefits in humans.