Protective Effects of the Flavonoid-Rich Fraction from Rhizomes of Smilax glabra Roxb. on Carbon Tetrachloride-Induced Hepatotoxicity in Rats

Advances in the chemical constituents, pharmacological activity, and clinical application of Smilacis Glabrae Rhizoma: A review and predictive analysis of quality markers (Q-markers)

Smilacis Glabrae Rhizoma (SGR) is recognized in traditional Chinese medicine for its distinctive therapeutic properties and abundant supply. Its phytochemical profile is diverse, encompassing flavonoids, steroids, saccharides, phenolic glycosides, volatile constituents, organic acids, phenylpropanoids, stilbenoids, among others. Recent pharmacological investigations reveal that SGR possesses a broad spectrum of pharmacological effects with multifaceted clinical applications. This review collates the current knowledge on SGR's chemical composition, pharmacological activities, and its clinical utility. Utilizing network pharmacology and molecular docking approaches, this study provides a preliminary identification of potential quality markers (Q-Markers) within SGR. The findings suggest that compounds such as astilbin, isoengelitin, neoisoastilbin, neoastilbin, astragaloside, diosgenin, resveratrol, stigmasterol, β-sitosterol, and quercetin in SGR are promising candidates for Q-Markers. While flavonoids are the most extensively studied, there is a pressing need to further explore the active monomeric compounds within SGR. The introduction of Q-Markers is instrumental in developing standardized quality metrics. Specifically, astilbin has been noted for its antitumor, antidiabetic, antihypertensive, anti-hyperuricemic, and hepatoprotective potential, warranting further research for therapeutic applications.

Polysaccharide from Smilax glabra Roxb Mitigates Intestinal Mucosal Damage by Therapeutically Restoring the Interactions between Gut Microbiota and Innate Immune Functions

Smilax glabra Roxb (S. glabra) is a conventional Chinese medicine that is mainly used for the reliability of inflammation. However, bioactive polysaccharides from S. glabra (SGPs) have not been thoroughly investigated. Here, we demonstrate for the first time that SGPs preserve the integrity of the gut epithelial layer and protect against intestinal mucosal injury induced by dextran sulfate sodium. Mechanistically, SGPs mitigated colonic mucosal injury by restoring the association between the gut flora and innate immune functions. In particular, SGPs increased the number of goblet cells, reduced the proportion of apoptotic cells, improved the differentiation of gut tight junction proteins, and enhanced mucin production in the gut epithelial layer. Moreover, SGPs endorsed the propagation of probiotic bacteria, including Lachnospiraceae bacterium, which strongly correlated with decreased pro-inflammatory cytokines via the blocking of the TLR-4 NF-κB and MyD88 pathways. Overall, our study establishes a novel use of SGPs for the treatment of inflammatory bowel disease (IBD)-associated mucosal injury and provides a basis for understanding the therapeutic effects of natural polysaccharides from the perspective of symbiotic associations between host innate immune mechanisms and the gut microbiome.

A comprehensive quality control evaluation for standard decoction of Smilax glabra Roxb based on HPLC-MS-UV/CAD methods combined with chemometrics analysis and network pharmacology

An effective, sensitive, and rapid method was developed for the quality control evaluation of the standard decoction of Smilax glabra Roxb (SGR). SGR is a primary ingredient of the traditional functional foods of turtle jelly and SGR tea. Chemometrics, Network Pharmacology, and molecular docking were used to screen for six quality markers. Multiple extraction parameters were optimized. HPLC-UV/CAD-QAMS was used to rapidly quantify the six quality markers (neoastilbin, astilbin, neoisoastilbin, isoastilbin, quercitrin, and isoengeletin) in 10 batches of the standard decoction of SGR samples. The relative correction factor (RCF) values of the five compounds were close to 1, demonstrating that the charged aerosol detection (CAD) showed a consistent response to compounds with similar parent nucleus structures. This method can serve as a guide for rapid quantitative analysis of the multi-components of the SGR standard decoction and all the traditional functional foods of turtle jelly with the homology of medicine.

Smilax glabra Roxb.: A Review of Its Traditional Usages, Phytochemical Constituents, Pharmacological Properties, and Clinical Applications

Smilax glabra Roxb. (SGB) is a medicinal plant widely distributed in 17 countries worldwide. It is the primary raw material of the world-famous and best-selling functional food and beneficial tea. SGB was first recorded in Ben Cao Jing Ji Zhu of the Southern and Northern Dynasties (420–589 AD) and was reported for nutritional and medicinal properties for thousands of years. This review searched PubMed, Web of Science, and other databases for relevant literature on SGB species until April 2022. It aims to provide more integrated thinking, detailed awareness, and better knowledge of SGB. More than 200 chemical components have been discovered, including flavonoids, phenolic, phenolic acids, stilbenes, organic acids, phenylpropanoids, and others. Previous studies have demonstrated that SGB and its active ingredients show a wide range of pharmacological effects, including anti-infective, anti-cancer, anti-inflammatory, antioxidant, cardiovascular protection, etc. However, many studies on the biological activity of this plant were mainly based on crude extracts and active ingredients, and there is a lack of clinical studies and toxicity studies to support the development of drug design, development, and therapy. In summary, this review will provide specific and valuable suggestions and guidelines for further research and application of this plant in the medicinal field.

Antioxidant and Anti-Inflammatory Activities of Six Flavonoids from Smilax glabra Roxb

This study aimed to isolate, prepare and identify the main flavonoids from a standardized Smilax glabra flavonoids extract (SGF) using preparative HPLC, MS, ¹H NMR and ¹³C NMR, determine the contents of these flavonoids using UPLC, then compare their pharmacological activities in vitro. We obtained six flavonoids from SGF: astilbin (18.10%), neoastilbin (11.04%), isoastilbin (5.03%), neoisoastilbin (4.09%), engeletin (2.58%) and (−)-epicatechin (1.77%). The antioxidant activity of six flavonoids were evaluated by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS⁺) radical scavenging activity and ferric reducing antioxidant power (FRAP). In addition, the anti-inflammatory activity of six flavonoids were evaluated by determining the production of cytokines (IL-1β, IL-6), nitric oxide (NO) using enzyme linked immunosorbent assay and the NF-κB p65 expression using Western blotting in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results showed that (−)-epicatechin, astilbin, neoastilbin, isoastilbin and neoisoastilbin had strong antioxidant activities, not only in DPPH and ABTS⁺ radicals scavenging capacities, but in FRAP system. Furthermore, all the six flavonoids could significantly inhibit the secretion of IL-1β, IL-6, NO (p < 0.01) and the protein expression of NF-κB p-p65 (p < 0.01) in LPS-stimulated RAW264.7 cells. This study preliminarily verified the antioxidant and anti-inflammatory activities of six flavonoids in S. glabra.

Protective Effects of Smilax glabra Roxb. Against Lead-Induced Renal Oxidative Stress, Inflammation and Apoptosis in Weaning Rats and HEK-293 Cells

Lead (Pb) is an important environmental pollutant. Oxidative stress and the inflammatory response have been postulated as mechanisms involved in lead-induced renal damage. Smilax glabra Roxb. has been used for treatment of heavy-metal poisoning in China for 500 years. We investigated S. glabra flavonoids extract (SGF) could attenuate lead acetate-induced nephrotoxicity in weaning rats and human embryonic kidney (HEK)-293 cells, and investigated the possible mechanisms. Compared with Pb exposed group of weaning rats, SGF could significantly promote lead excretion in the blood and kidney, and increase the content of the renal-function indicators blood urea nitrogen, serum uric acid, and serum creatinine. SGF could improve the glomerular filtration rate (GFR) and histologic changes in the kidneys of weaning rats exposed to Pb. SGF could also reduce lead-induced cytotoxicity, improve DNA damage-induced apoptosis and cleaved caspase-3-mediated apoptosis in HEK-293 cells stimulated with Pb. SGF significantly increased the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase and catalase, and decreased excessive release of reactive oxygen species (ROS) and malondialdehyde in the kidneys of the weaning rats and in HEK-293 cells. The antioxidant mechanism of SGF related to activation of the Kelch-like ECH-associated protein 1/nuclear-factor-E2-related factor 2/hemeoxygenase-1(Keap1/Nrf2/HO-1) pathway. SGF could inhibit secretion of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α induced by Pb in vivo and in vitro. The anti-inflammatory mechanism of SGF related to inhibition of ROS and pro-inflammatory cytokines triggered the nuclear factor-kappa B (NF-κB) pathway through blockade of inhibitors of I-κB degradation, phosphorylation of NF-κB p65, and nuclear translocation of p65. Our findings indicate that SGF could be a natural antioxidant and anti-inflammatory agent for treating lead-induced nephrotoxicity.

The flavonoid-rich fraction from rhizomes of Smilax glabra Roxb. ameliorates renal oxidative stress and inflammation in uric acid nephropathy rats through promoting uric acid excretion

Uric acid metabolic disorder is considered to be the main pathogenesis of uric acid nephropathy (UN). Smilax glabra Roxb. is a traditional Chinese herb which has been used in the treatment of gout, but the mechanism was unclear. In this study, we investigated the protective effects of the flavonoid-rich fraction from rhizomes of Smilax glabra Roxb. (SGF) on uric acid nephropathy rats and its underlying mechanisms of promoting uric acid excretion. Sprague Dawley (SD) rats were induced by high purine diet (yeast pellets + adenine) for 5 weeks. Rats were orally treated with SGF or allopurinol daily. The biochemical parameters and enzymes in different treated rats were determined by commercial kits. Kidney pathology was visualized using optical microscopy and electron microscopy. Renal inflammatory factors were detected by ELISA. Renal fibrosis factors and uric acid transporters were analyzed by real time RT-PCR and western blot. The results showed that SGF significantly improved kidney function. Histopathologic examination revealed that urate-induced renal damage was markedly reversed by SGF. Meanwhile, SGF treatment was also found to significantly inhibit renal oxidative stress. SGF treatment obviously suppressed the inflammatory factors of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and the profibrotic factors of basic fibroblast growth factor (bFGF), transforming growth factor-β₁ (TGF-β₁) expression in UN rats. Moreover, SGF either significantly inhibited uric acid production or promoted uric acid excretion in UN rats. The mechanism of SGF promoting uric acid excretion was related to its increase of ATP-binding cassette transporter G2 (ABCG2), organic anion transporter 1 (OAT1), organic anion transporters 2 (OCT2) and organic cation/carnitine transporters 2 (OCTN2) expression. In conclusion, SGF could ameliorate renal oxidative stress and inflammation in UN rats through promoting uric acid excretion.

Ethnomedicine, Phytochemistry and Pharmacology of Smilax glabra: An Important Traditional Chinese Medicine

Smilax glabra (SG) Roxb., a well-known traditional Chinese medicine, has been extensively used worldwide for its marked pharmacological activities for treating syphilitic poisoned sores, limb hypertonicity, morbid leucorrhea, eczema pruritus, strangury due to heat, carbuncle toxin, and many other human ailments. Approximately 200 chemical compounds have been isolated from SG Roxb., and the major components have been determined to be flavonoids and flavonoid glycosides, phenolic acids, and steroids. Among these active compounds, the effects of astilbin, which is used as a quality control marker to determine the quality of SG Roxb., have been widely investigated. Based on in vivo and in vitro studies, the primary active components of SG Roxb. possess various pharmacological activities, such as cytotoxic, anti-inflammatory and immune-modulatory effects, anti-oxidant, hepatoprotective, antiviral, antibacterial, and cardiovascular system protective activities. However, an extensive study to determine the relationship between the chemical compositions and pharmacological effects of SG Roxb. has not been conducted and is worth of our study. Improving the means of utilizing the effects of SG is crucial. The present paper reviews the ethnopharmacology, phytochemistry, and pharmacology of SG Roxb. and assesses its ethnopharmacological use in order to explore its therapeutic potential for future research.

Smilax glabra Rhizoma affects the pharmacokinetics and tissue distribution of methotrexate by increasing the P‑glycoprotein mRNA expression in rats after oral administration

Methotrexate (MTX) is a widely used immunosuppressant and anticancer agent with high toxicity. Smilax glabra Rhizoma (SGR) has the effect of detoxification and immunoregulation, and has been used as both food and folk medicine in many countries. Co‑administration of MTX and SGR occurs in several diseases. However, whether they work synergistically or are incompatible remains unknown. In the present study, MTX was administrated to rats alone or combined with SGR. Blood and tissue samples were collected at designated times. The concentrations of MTX were determined by high‑performance liquid chromatography. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to detected the gene expression. SGR decreased the AUC0‑t and Cmax of MTX by 44.5 and 48.2%, but in a tissue‑dependent manner. The total exposure of MTX was significantly decreased in the small intestine, stomach, plasma, and kidney by 61.6, 34.7, 63.3 and 46.1%, respectively, but was increased in the lung and spleen by 82.9 and 21.0%, respectively. RT‑qPCR demonstrated that SGR increased the mean P‑glycoprotein (gp) mRNA expression in the small intestine 2.54 times, but had a marginal effect on the expression of organic anion transporting polypeptide 2, and organic anion transporter (OAT)1 and OAT2. These results suggested that SGR affects the pharmacokinetics of MTX in a tissue‑dependent manner by affecting P‑gp, and the clinical effect of co‑administration depended on the disease site.

Treatment and management of liver diseases by Khmer traditional healers practicing in Phnom Penh area, Cambodia

ETHNOPHARMACOLOGICAL RELEVANCE

Liver disorders are a major health problem in Cambodia, where some patients prefer to seek treatment from traditional healers. The aim of the study was to document the knowledge and practices of these healers in four Southern Cambodian provinces.

MATERIALS AND METHODS

An ethnopharmacological survey was carried out from September 2015 to January 2016 in Cambodian urban and rural areas. Thirty-three Khmer traditional healers (KTH) were interviewed using a semi-structured questionnaire including socio-demographic data, healer's formation and their professional practice conditions, perception of liver diseases (types and causes of liver disorders, diagnostic methods and symptoms of liver problems), dietary recommendations given to patients, and herbal remedies used to treat them. For each medicinal plant mentioned in herbal remedies, the local name, part of the plant, mode of preparation and administration, and their properties, according to the healers, were recorded. The plants mentioned by the traditional therapists were collected and later identified by specialists.

RESULTS

Different types of liver disease are identified by the healers, and diagnosis was mostly based on reading medical records, and by observing the yellow discoloration of the skin and eyes. A total of 42 herbal remedies including 83 medicinal plants belonging to 40 families were mentioned for treating liver disorders. The most predominant families were Leguminosae and Poaceae. Among the plants reported, Cananga latifolia, Andrographis paniculata, Smilax aff. glabra, Gomphrena celosioides, Passiflora foetida and Physalis minima were the most cited species. A large part of the herbal remedies used were multi-ingredient recipes, and were prepared mainly by a decoction administered orally. Plants are combined in multi-ingredient recipes, and selected on the basis of their properties (trocheak, psah, somrap mé rok, ktchol) which originate from Khmer medical concepts. Most of the plants used by healers have a wide ethnobotanical use for liver disorders, and have been studied for their hepatoprotective activity and related activities on the liver.

CONCLUSION

In the diagnosis and treatment of liver diseases, KTH have incorporated biomedical concepts and new practices, which suggest that they could be defined as neotraditional healers. Medicinal plants constitute the core of traditional medicine practice by these healers, and these plants play a very important role in the health care of people with liver problems in Cambodia. Therefore, more attention should be paid to the integration of healers in national health care programs for the development of combined therapies. Furthermore, two plant species (i.e. Cananga latifolia and Willughbeia edulis) were found to be widely used for treating liver disorders in our survey, and should be studied for their pharmacological potential for liver problems.

Differences in antioxidant activities of outdoor- and indoor-cultivated Agaricus brasiliensis, and protective effects against carbon tetrachloride-induced acute hepatic injury in mice

Background

Agaricus brasiliensis (A. brasiliensis) is a medicinal mushroom that exerts various pharmacological actions. We previously demonstrated that different cultivation conditions altered the activity of the polyphenol-related enzymes from this mushroom. However, the influence of cultivation conditions on the antioxidant activity of the fruiting bodies remains unclear. Therefore, in this study we compared the antioxidative effects of fruiting bodies of A. brasiliensis cultivated outdoors and indoors. In addition, we assessed whether different cultivation methods affected the hepatoprotective effects against CCl₄-induced liver injury.

Methods

We assessed the antioxidative effects of mushrooms cultivated in open-air or indoors using the DPPH radical-scavenging assay. Furthermore, we prepared experimental feeds containing outdoor- or indoor-cultivated A. brasiliensis. Acute liver injury was induced by CCl₄ injection in mice that consumed feed containing outdoor- or indoor-cultivated A. brasiliensis. The hepatoprotective effects of these mushrooms were then evaluated by monitoring the reduction in the circulating levels of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase. The significance of the differences between the means was assessed using Student’s t-test. Finally, histopathological analysis of liver was performed.

Results

In the DPPH assay, the antioxidant activity of outdoor-cultivated A. brasiliensis was higher than that of indoor-cultivated mushroom. Moreover, in the mouse model of CCl₄-induced hepatitis, the oral administration of outdoor-cultivated A. brasiliensis reduced liver damage significantly, but indoor-cultivated mushrooms failed to inhibit hepatitis. The hepatoprotective effects of outdoor-cultivated A. brasiliensis were observed even when ingestion commenced only 1 day before CCl₄ injection, and these effects were not affected by excessive heat treatment.

Conclusions

Outdoor cultivation significantly enhanced the antioxidative activity of A. brasiliensis fruiting bodies. In addition, outdoor-cultivated A. brasiliensis was more effective at protecting against CCl₄-induced liver injury in mice than mushrooms grown in a greenhouse.

Palm kernel cake extract exerts hepatoprotective activity in heat-induced oxidative stress in chicken hepatocytes

BACKGROUND

Palm kernel cake (PKC), the most abundant by-product of oil palm industry is believed to contain bioactive compounds with hepatoprotective potential. These compounds may serve as hepatoprotective agents which could help the poultry industry to alleviate adverse effects of heat stress on liver function in chickens.

METHODS

This study was performed to evaluate the hepatoprotective potential of PKC extract in heat-induced oxidative stress in chicken hepatocytes. The nature of the active metabolites and elucidation of the possible mechanism involved were also investigated.

RESULTS

The PKC extract possessed free radical scavenging activity with values significantly (p < 0.05) lower than silymarin as the reference antioxidant. Heat-induced oxidative stress in chicken hepatocyte impaired the total protein, lipid peroxidation and antioxidant enzymes activity significantly (p < 0.05). Treatment of heat-induced hepatocytes with PKC extract (125 μg/ml) and silymarin as positive control increased these values significantly (p < 0.05). The real time PCR and western blot analyses revealed the significant (p < 0.05) up-regulation of oxidative stress biomarkers including TNF-like, IFN-γ and IL-1β genes; NF-κB, COX-2, iNOS and Hsp70 proteins expression upon heat stress in chicken hepatocytes. The PKC extract and silymarin were able to alleviate the expression of all of these biomarkers in heat-induced chicken hepatocytes. The gas chromatography-mass spectrometry analysis of PKC extract showed the presence of fatty acids, phenolic compounds, sugar derivatives and other organic compounds such as furfural which could be responsible for the observed hepatoprotective activity.

CONCLUSION

Palm kernel cake extract could be a potential agent to protect hepatocytes function under heat induced oxidative stress.

Nrf2 pathway activation contributes to anti-fibrosis effects of ginsenoside Rg1 in a rat model of alcohol- and CCl4-induced hepatic fibrosis

AIM

To investigate the anti-fibrosis effects of ginsenoside Rg1 on alcohol- and CCl4-induced hepatic fibrosis in rats and to explore the mechanisms of the effects.

METHODS

Rats were given 6% alcohol in water and injected with CCl4 (2 mL/kg, sc) twice a week for 8 weeks. Rg1 (10, 20 and 40 mg/kg per day, po) was administered in the last 2 weeks. Hepatic fibrosis was determined by measuring serum biochemical parameters, HE staining, Masson's trichromic staining, and hydroxyproline and α-SMA immunohistochemical staining of liver tissues. The activities of antioxidant enzymes, lipid peroxidation, and Nrf2 signaling pathway-related proteins (Nrf2, Ho-1 and Nqo1) in liver tissues were analyzed. Cultured hepatic stellate cells (HSCs) of rats were prepared for in vitro studies.

RESULTS

In the alcohol- and CCl4-treated rats, Rg1 administration dose-dependently suppressed the marked increases of serum ALT, AST, LDH and ALP levels, inhibited liver inflammation and HSC activation and reduced liver fibrosis scores. Rg1 significantly increased the activities of antioxidant enzymes (SOD, GSH-Px and CAT) and reduced MDA levels in liver tissues. Furthermore, Rg1 significantly increased the expression and nuclear translocation of Nrf2 that regulated the expression of many antioxidant enzymes. Treatment of the cultured HSCs with Rg1 (1 μmol/L) induced Nrf2 translocation, and suppressed CCl4-induced cell proliferation, reversed CCl4- induced changes in MDA, GPX, PCIII and HA contents in the supernatant fluid and α-SMA expression in the cells. Knockdown of Nrf2 gene diminished these actions of Rg1 in CCl4-treated HSCs in vitro.

CONCLUSION

Rg1 exerts protective effects in a rat model of alcohol- and CCl4-induced hepatic fibrosis via promoting the nuclear translocation of Nrf2 and expression of antioxidant enzymes.

Fermentation of Smilax china root by Aspergillus usami and Saccharomyces cerevisiae promoted concentration of resveratrol and oxyresveratrol and the free-radical scavenging activity

BACKGROUND

Smilax china root, which is rich in resveratrol and oxyresveratrol, has been used as emergency foods as well as folk medicine. This study investigated changes in concentration of bioactive components and the free-radical scavenging capacity of Smilax china root during fermentation by Aspergillus usami and Saccharomyces cerevisiae.

RESULTS

Resveratrol, oxyresveratrol and piceid were quantified as major constituents in Smilax china root by using UPLC-ESI-MS. The concentration of oxyresveratrol and resveratrol remarkably increased through fermentation and the transformation of piceid to resveratrol. Its concentration in 4% Smilax china root was 1.16-2.95 times higher than that of a 2% preparation throughout fermentation. The vitamin C equivalent antioxidant capacity of 2% Smilax china root was 1.51-1.91 times higher than that of 4% Smilax china root during fermentation. Meanwhile, ABTS free-radical scavenging capacity was enhanced up to 95.07 and 99.35% for 2% and 4% Smilax china root, respectively.

CONCLUSION

Results from our study propose that bioactive components in Smilax China root were highly extracted by fermentation followed by saccharification and ethanol production, resulting in enhanced free-radical scavenging capacity. © 2013 Society of Chemical Industry.