Inhibition of mouse skin tumor-initiating activity of DMBA by chronic oral feeding of glycyrrhizin in drinking water

Glycyrrhizic acid facilitates anti-tumor immunity by attenuating Tregs and MDSCs: An immunotherapeutic approach

Melanoma is one of the most aggressive malignancies and its treatment remains challenging due to its highly metastatic property and availability of limited effective drugs. In addition, immunosuppresive tumor microenvironment (TME) has been identified as major barrier to evoke anti-tumor response in melanoma. Recent studies revealed that immunosuppressive TME is directly correlated with heightened activations of T regulatory cells (Tregs) and Myeloid derived suppressor cells (MDSCs) functions. In this study, we investigated the anti-cancer effect of a triterpenoid, glycyrrhizic acid (GA) on melanoma. Our study revealed that GA not only exhibited anti-proliferative effects on melanoma cells it significantly restricted progression of melanoma tumor. However, the therapeutic efficacy of GA in impressive regression of tumor was found to be directly correlated with induction of apoptosis and modulation of cytokines from Th2 to Th1 type. To unravel the mechanism of anti-melanoma effect of GA, it has been delineated that GA inhibits pSTAT3 to evade anti-tumor suppressive function of Tregs and MDSCs. Downregulation of FOXP3, GITR and CTLA4 in tumor-infiltrating Tregs and inhibition of Cox2, PGE2 and Arginase 1 in intra-tumoral MDSC were evidenced as some of the key events during therapeutic intervention of GA in melanoma management. Moreover, GA effectively restricted advanced stage solid tumor while used in combination with Mycobacterium indicus pranii, a known immunomodulator, which alone is reported to be ineffective to restrict advanced stage solid tumor. Thus, our findings may open up a novel insight of GA as a promising agent in cancer immunotherapy or adjuvant therapy in future.

Glycyrrhiza glabra L. (Fabaceae/Leguminosae)

Liquorice is a perennial, temperate-zone herb or subshrub, native of India, Pakistan and southern Europe; also cultivated in England, Belgium, France, Germany, Spain, Italy, Greece, Turkey, Russia, South Africa, Egypt, Syria and Iraq. It has also been grown experimentally in the United States. Ancient historical manuscripts from China, India and Greece mention its use for symptoms of viral respiratory tract infections and hepatitis. The plant has also been described by Theophrastus. Licorice from Egypt has been described to be the best, followed by from Iraq and Syria; the root should be decorticated before use. It concocts viscid humours in diseases of liver, bladder and lungs, and expectorates them. It has been used in Iranian herbal medicine for skin eruptions, including dermatitis, eczema, pruritus and cysts, and for treatment of stomach disorders including peptic ulcers. The herb extract inhibits gastric motility in vivo, which is regarded to be an important aspect for its antiulcer activity. Licorice possesses both anti-inflammatory and antiulcer activities; whereas most anti-inflammatory agents are ulcerogenic. Former German Commission E believed it to be effective in the treatment of atopic dermatitis. Licorice root has been used for years to regulate gastrointestinal function in TCM, has been used for generations as an antidote, demulcent, and elixir in folk medicine of China, and is the most commonly used crude drug in Kampo Medicines, the Japanese form of modified TCM, for the treatment of peptic ulcer. Roots contain glycyrrhizin, the main water-soluble constituent that is 50× sweeter than sugar, 2-β-glucuronosyl glucuronic acid, and isoliquiritigenin-4-glucoside. Glycyrrhizin is a nonhemolytic saponin with foaming property, and one of the most potent hydroxyl radical scavengers. No significant effect of deglycyrrhizinised liquorice was observed on gastric ulcer in an RCT of British patients. Treatment of healthy men with licorice for one-week decreased salivary testosterone values by 26% but no significant decrease in free testosterone, and nine healthy women treated with licorice daily for two cycles, had their mean total serum testosterone decreased by 37% at the end of 2nd month. This property could be useful as an adjunct therapy of hirsutism and PCOS.

Glycyrrhizic acid suppresses 1,2-dimethylhydrazine-induced colon tumorigenesis in Wistar rats: Alleviation of inflammatory, proliferation, angiogenic, and apoptotic markers

OBJECTIVES

Colon cancer is the major health disease related with high mortality. Glycyrrhizic acid (GA) is an active constituent of licorice with anti-inflammatory and anticarcinogenesis effects. We investigated the chemopreventive potential of GA against 1,2-dimethylhydrazine (DMH)-induced colon tumorigenesis in Wistar rats.

METHODS

Glycyrrhizic acid was administered orally at the dose of 15 mg/kg b.wt. and DMH was administered at the dose of 20 mg/kg b.wt. once a week for first 15 weeks. All the rats were euthanized after 30 weeks. GA supplementation significantly inhibited the tumor incidence and multiplicity.

RESULTS

Glycyrrhizic acid treatment reduced the expression of Ki-67, proliferating cell nuclear antigen (PCNA), nuclear factor-kappa B (NF-kB), cyclooxygenase-2 (COX-2), induced nitric oxide synthase (iNOS), and vascular endothelial growth factor (VEGF) while enhanced the expression of p53, connexin-43, b-cell lymphoma-2 (Bcl-2), survivin, and cleaved caspase-3. Glycyrrhizic acid also significantly ameliorated DMH-induced decreased activities of caspase-9 and caspase-3. Furthermore, GA treatment reduced mast cells infiltration, attenuated the shifting of sialomucin to sulphomucin as well the levels of pro-inflammatory cytokines.

CONCLUSION

The findings of the study suggest that GA has chemopreventive potential against DMH-induced colon tumorigenesis plausibly through the attenuation of hyperproliferative responses, pro-inflammatory cytokines level, inflammatory and angiogenic markers, and apoptotic responses.

18 beta-glycyrrhetinic acid ameliorates the cognitive functions and decreases the recurrence rate of pituitary adenomas patients

Pituitary adenomas, the most common tumors of all intracranial neoplasms, may cause either symptoms of mass effect or symptoms of hormone abnormal production. Besides physical damages, patients with pituitary adenomas always suffer from cognitive impairments, mainly in memory and executive functions. 18 beta-glycyrrhetinic acid (GA) has been found to exhibit anti-tumor effects in rat pituitary adenoma-derived cells. The aim of this paper was to investigate the effect of GA in postoperative clinical application. In this study, we recruited 647 patients with pituitary adenoma and 135 patients who dropped out were excluded from analysis. Thus, altogether 512 patients with pituitary adenoma completed the study, of whom 268 were treated with GA, and 244 were treated with placebo. Cognitive assessments, eyesight, tumor size, and hormone secretion levels were examined before and after surgery in both groups. All patients underwent surgeries by single-nostril transsphenoidal approach for their first-time medical treatment. Hormone secretion levels were measured by blood samples and Magnetic resonance imaging (MRI) was used for examining the status of tumor excision. Compared with placebo group, the scores in orientation, language (expression), memory (recall), practice, abstract thinking, and MiniMental State Examination (MMSE) were significantly improved (p < 0.05) in GA treated group after one month of surgery. After six months, there was still a significant increase in abstract thinking scores. Moreover, GA did not impact the overall survival percentage of patients enrolled during our five-year follow-up, but significantly reduced the recurrence rate than that of the placebo group. GA significantly improved the cognitive functions at the early stage after surgery and had a long-termed efficacy on abstract thinking. Notably, GA inhibited the five-year recurrence rate of the recruited pituitary adenomas patients.

Reversal of Doxorubicin-induced Cardiotoxicity by Using Phytotherapy: A Review

Doxorubicin as a chemotherapeutic drug is widely used for the treatment of patients with cancer. However, clinical use of this drug is hampered by its cardiotoxicity, which is manifested as electrocardiographic abnormalities, arrhythmias, irreversible degenerative cardiomyopathy and congestive heart failure. The precise mechanisms underlying the cardiotoxicity of doxorubicin are not clear, but impairment of calcium homeostasis, generation of iron complexes, production of oxygen radicals, mitochondrial dysfunction and cell membrane damage have been suggested as potential etiologic factors. Compounds that can neutralize the toxic effect of doxorubicin on cardiac cells without reducing the drug's antitumor activity are needed. In recent years, numerous studies have shown that herbal medicines and bioactive phytochemicals can serve as effective add-on therapies to reduce the cardiotoxic effects of doxorubicin. This review describes different phytochemicals and herbal products that have been shown to counterbalance doxorubicin-induced cardiotoxicity.

Toxicological Effects of Glycyrrhiza glabra (Licorice): A Review

Licorice (Glycyrrhiza glabra) has been considered as an herbal drug since ancient time. Nowadays, it is a well-known spice that possesses worth pharmacological effects. However, some relevant articles have revealed negative impacts of licorice in health. By considering the great wishes in using herbal medicine, it is important to show adverse effects of herbal medicine in health. At present, there are misunderstandings toward the safety of herbal medicines. Herein, we gathered scientific research projects on the toxicity effects of licorice and glycyrrhizin to highlight their safety. In this regards, we categorized our findings about the toxicity effects of licorice and glycyrrhizin in acute, sub-acute, sub-chronic, and chronic states. Besides, we discussed on the cytotoxicity, genotoxicity, mutagenicity, and carcinogenicity of licorice and glycyrrhizin as well as their developmental toxicity. This review disclosed that G. glabra and glycyrrhizin salts are moderately toxic. They need to be used with caution during pregnancy. G. glabra and glycyrrhizin possess selective cytotoxic effects on cancerous cells. The most important side effects of licorice and glycyrrhizin are hypertension and hypokalemic-induced secondary disorders. Licorice side effects are increased by hypokalemia, prolonged gastrointestinal transient time, decreased type 2 11-beta-hydroxysteroid dehydrogenase activities, hypertension, anorexia nervosa, old age, and female sex. Copyright © 2017 John Wiley & Sons, Ltd.

Mutagenicity and cytotoxicity of fruits and vegetables evaluated by the Ames test and 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay / Mutagenicidad y citotoxicidad de frutas y vegetales evaluadas por el test de Ames y el ensayo del bromuro de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolio (MTT)

The mutagenic and cytotoxic activity of the aqueous (H2O) and ethanolic (EtOH) extracts of fruits and vegetables were studied by the Ames test and the MTT assay. A significant mutagenic activity was found for three H2O extracts of broccoli ( Brassica oleracea), carrot ( Dacus carota) and licorice ( Glycyrrhiza glabra) and for one EtOH extract of kiwi ( Ananas sativus ) of the nine species analyzed. The frameshift tester strain TA98 was reverted by broccoli (2.4, 4.8 and 9.6 mg/mL; p < 0.01) and carrot (9.6 mg/mL; p < 0.001) aqueous extracts and by kiwi (9.6 mg/mL; p < 0.0001) EtOH extract, whereas strain TA100 was only sensitive to the mutagens of licorice H,O extract, within the nine fruits and vegetables tested. The mutagenic response of the extracts was not altered by the presence of S9 mix. Cytotoxicity was only found for three of the nine species tested. Percentage cytotoxic ac tivities at 4.8 mg/mL in pineapple ( Actinidin diasinensis) and garlic ( Allium sativum) H,O extracts were 77 and 91 %, respectively. Licorice EtOH extract was the only one that showed a cytotoxic activity at all of the concentrations used. The percentage of cytotoxic activity of licorice extract was 63% at 0.24 mg/mL and increased with increasing concentration of licorice up to 4.8 mg/mL. Thus, licorice (EtOH) extract was the most cytotoxic of the species tested.

Glycyrrhiza glabra

Liquorice foliage

Glycyrrhizic acid (GA) inhibits reactive oxygen Species mediated photodamage by blocking ER stress and MAPK pathway in UV-B irradiated human skin fibroblasts

BACKGROUND

Previously we have reported that generation of reactive oxygen species is the prime event responsible for calcium mediated activation of PERK-eIF2α-CHOP pathway and apoptosis in UV-B irradiated human skin fibroblasts (Hs68). We have also reported that glycyrrhizic acid (GA) mediates potent photoprotective activity against UV-B - irradiation-induced photodamage in human skin fibroblast.

OBJECTIVE

In the present study, we aimed to investigate the role of GA in preventing oxidative stress mediated unfolded protein response (UPR) and mitogen activated protein kinases (MAPK) pathway.

METHODS

Human skin fibroblast (Hs68) cells were exposed to UV-B radiations in lab conditions. Different parameters of UVB induced cellular and molecular changes were analysed using western-blotting, microscopy and flow cytometry.

RESULTS

Our results show that GA has strong photoprotective action against UV-B induced cellular damage. It was observed that: (a) Oxidative disturbances and intracellular Ca(2+) imbalance induced by UV-B irradiation was significantly restored by GA treatment; (b) activation of PERK-eIF2α-CHOP and MAPK pathway induced by UV-B was significantly blocked by GA; (c) Loss of mitochondrial membrane potential and apoptosis induced by UV-B were reduced by GA treatment.

CONCLUSION

Based on the above findings we conclude GA has a highly significant ROS quenching activity, thereby blocking the cascade of events including release of calcium from ER and subsequent ER stress, MAPK pathway and cellular demise. GA offers highly potent anti photodamage effect and can be exploited for cosmetic or therapeutic purposes.

Licochalcone A, a polyphenol present in licorice, suppresses UV-induced COX-2 expression by targeting PI3K, MEK1, and B-Raf

Licorice is a traditional botanical medicine, and has historically been commonly prescribed in Asia to treat various diseases. Glycyrrhizin (Gc), a triterpene compound, is the most abundant phytochemical constituent of licorice. However, high intake or long-term consumption of Gc has been associated with a number of side effects, including hypertension. However, the presence of alternative bioactive compounds in licorice with anti-carcinogenic effects has long been suspected. Licochalcone A (LicoA) is a prominent member of the chalcone family and can be isolated from licorice root. To date, there have been no reported studies on the suppressive effect of LicoA against solar ultraviolet (sUV)-induced cyclooxygenase (COX)-2 expression and the potential molecular mechanisms involved. Here, we show that LicoA, a major chalcone compound of licorice, effectively inhibits sUV-induced COX-2 expression and prostaglandin E2 PGE₂ generation through the inhibition of activator protein 1 AP-1 transcriptional activity, with an effect that is notably more potent than Gc. Western blotting analysis shows that LicoA suppresses sUV-induced phosphorylation of Akt/ mammalian target of rapamycin (mTOR) and extracellular signal-regulated kinases (ERK)1/2/p90 ribosomal protein S6 kinase (RSK) in HaCaT cells. Moreover, LicoA directly suppresses the activity of phosphoinositide 3-kinase (PI3K), mitogen-activated protein kinase kinase (MEK)1, and B-Raf, but not Raf-1 in cell-free assays, indicating that PI3K, MEK1, and B-Raf are direct molecular targets of LicoA. We also found that LicoA binds to PI3K and B-Raf in an ATP-competitive manner, although LicoA does not appear to compete with ATP for binding with MEK1. Collectively, these results provide insight into the biological action of LicoA, which may have potential for development as a skin cancer chemopreventive agent.

Chemopreventive Effects of Licorice and Its Components

Cancer is still a major health issue worldwide and identifying novel but safe compounds for prevention and treatment is a high priority. Licorice (Glycyrrhiza) is a perennial plant that is cultivated in many countries and has been reported to exert antioxidant, anti-inflammatory and anticancer effects. However, some components of licorice exert unwanted side effects and therefore identifying safer licorice components would be ideal. The anticancer activities of many of the licorice components appear to include cycle arrest, apoptosis induction, and general antioxidant effects. Commonly reported indirect protein targets important in tumorigenesis include many cell cycle-related proteins, apoptosis-associated proteins, MMP proteins, COX-2, GSK-β, Akt, NF-κB, and MAP kinases. Importantly, several licorice components were reported to directly bind to and inhibit the activities of PI3-K, MKK4, MKK7, JNK1, mTOR, and Cdk2, resulting in decreased carcinogenesis in several cell and mouse models with no obvious toxicity. This review focuses on specific components of licorice for which a direct protein target has been identified.

Toll-like receptor 4 ablation in mdx mice reveals innate immunity as a therapeutic target in Duchenne muscular dystrophy

Toll-like receptor 4 (TLR4) recognizes specific structural motifs associated with microbial pathogens and also responds to certain endogenous host molecules associated with tissue damage. In Duchenne muscular dystrophy (DMD), inflammation plays an important role in determining the ultimate fate of dystrophic muscle fibers. In this study, we used TLR4-deficient dystrophic mdx mice to assess the role of TLR4 in the pathogenesis of DMD. TLR4 expression was increased and showed enhanced activation following agonist stimulation in mdx diaphragm muscle. Genetic ablation of TLR4 led to significantly increased muscle force generation in dystrophic diaphragm muscle, which was associated with improved histopathology including decreased fibrosis, as well as reduced pro-inflammatory gene expression and macrophage infiltration. TLR4 ablation in mdx mice also altered the phenotype of muscle macrophages by inducing a shift toward a more anti-inflammatory (iNOS(neg) CD206(pos)) profile. In vitro experiments confirmed that lack of TLR4 is sufficient to influence macrophage activation status in response to classical polarizing stimuli such as IFN-gamma and IL-4. Finally, treatment of dystrophic mice with glycyrrhizin, an inhibitor of the endogenous TLR4 ligand, high mobility group box (HMGB1), also pointed to involvement of the HMGB1-TLR4 axis in promoting dystrophic diaphragm pathology. Taken together, our findings reveal TLR4 and the innate immune system as important players in the pathophysiology of DMD. Accordingly, targeting either TLR4 or its endogenous ligands may provide a new therapeutic strategy to slow disease progression.

Effects of Chinese herbal medicine in combination with mitomycin C on gastric cancer cells

Chinese herbal medicine (CHM) is frequently used by cancer patients in Chinese community. It remains largely unknown about the interaction between CHM and chemotherapeutic agents. Herein, we evaluated 3 commonly used CHM formulas for cancer patients: Bu-Zhong-Yi-Qi-Tang (BZYQT), Bao-Yuan-Tang (BYT), and Ju-Yuan-Jian (JYJ). We examined the effects of these 3 formulas in human gastric cancer cells MKN-74, in terms of cytotoxicity and apoptosis induction when used alone or in combination with mitomycin C (MMC). Cytotoxicity was determined by tetrazolium dye colorimetric assay. The 10% inhibitory concentration of CHM was used in this study. Cells were first exposed to CHM or phosphate buffered saline (as control) for 48 h. Then MMC at final concentration of 0.25 μg/ml was added to media for another 24-h. Among these 3 CHM formulas, BZYQT showed the most pronounced effect in augmenting MMC-induced cytotoxicity. The viability of MKN-74 cells was decreased to 43.1% when treated with BZYQT and MMC, compared to 94.9% with MMC alone. We subsequently examined apoptosis induction by quantitative florescent microscopy and single-strand DNA enzyme-linked immunosorbent assay, and found BZYQT did not enhance MMC-induced apoptosis. Our findings indicate BZYQT in combination with MMC induces cell death in gastric cancer cells via non-apoptotic mechanism. Our results provide a rationale for further investigation in the interaction of CHM and anti-cancer treatment.

Glycyrrhizic acid suppresses the development of precancerous lesions via regulating the hyperproliferation, inflammation, angiogenesis and apoptosis in the colon of Wistar rats

Background

Colon carcinogenesis is a multistep process and it emanates from a series of molecular and histopathological alterations. Glycyrrhizic acid (GA) is a natural and major pentacyclic triterpenoid glycoside of licorice roots extracts. It has several pharmacological and biological properties such as anti-inflammatory, anti-viral, and anti-cancer. In the present study, we investigated the chemopreventive potential of GA against 1,2-dimethyhydrazine (DMH)-induced precancerous lesions i.e., aberrant crypt foci (ACF) and mucin depleted foci (MDF), and its role in regulating the hyperproliferation, inflammation, angiogenesis and apoptosis in the colon of Wistar rats.

Methods

Animals were divided into 5 groups. In group III, IV and V, GA was administered at the dose of 15 mg/kg b. wt. orally while in group II, III and IV, DMH was administered subcutaneously in the groin at the dose of 20 mg/kg b.wt once a week for first 5 weeks and animals were euthanized after 9 weeks.

Results

GA supplementation suppressed the development of precancerous lesions and it also reduced the infiltration of mast cells, suppressed the immunostaining of Ki-67, NF-kB-p65, COX-2, iNOS and VEGF while enhanced the immunostaining of p53, connexin-43, caspase-9 and cleaved caspase-3. GA treatment significantly attenuated the level of TNF-α and it also reduced the depletion of the mucous layer as well as attenuated the shifting of sialomucin to sulphomucin.

Conclusion

Our findings suggest that GA has strong chemopreventive potential against DMH-induced colon carcinogenesis but further studies are warranted to elucidate the precise mechanism of action of GA.

Cardioprotective effects of Glycyrrhiza uralensis extract against doxorubicin-induced toxicity

The purpose of the present study was to investigate the cardioprotective effects of Glycyrrhiza uralensis extract (GUE) against doxorubicin (DOX)-induced cardiotoxicity. Imprinting control region (ICR) mice were treated with saline, DOX (20 mg/kg intraperitoneal [ip] for once), GUE (100 mg/kg intragastric [ig] for 8 days), co-treatments with DOX and GUE (100 mg/kg ig for 8 days), and amifostine (100 mg/kg intravenous [iv] for once), respectively. Serum levels of lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK-MB), glutathione peroxidase (GSH-P(X)) activity, and glutathione (GSH) level in heart tissue were measured. Histopathologic analysis of heart tissue was also performed. Treatment with GUE significantly protected the mice from DOX-induced cardiotoxicity, indicated by decreased levels of serum LDH and CK-MB, improved heart morphology and increased GSH-P(X) activity and GSH level. Additionally, GUE did not compromise the tumor-inhibitory effect of DOX. In conclusion, our studies imply the potentially clinical application of GUE to overcome the cardiotoxicity of doxorubicin.

Inhibition of metastasis, angiogenesis, and tumor growth by Chinese herbal cocktail Tien-Hsien Liquid

Background

Advanced cancer is a multifactorial disease that demands treatments targeting multiple cellular pathways. Chinese herbal cocktail which contains various phytochemicals may target multiple dys-regulated pathways in cancer cells and thus may provide an alternative/complementary way to treat cancers. Previously we reported that the Chinese herbal cocktail Tien-Hsien Liguid (THL) can specifically induce apoptosis in various cancer cells and have immuno-modulating activity. In this study, we further evaluated the anti-metastatic, anti-angiogenic and anti-tumor activities of THL with a series of in vitro and in vivo experiments.

Methods

The migration and invasion of cancer cells and endothelial cells was determined by Boyden chamber transwell assays. The effect of THL on pulmonary metastasis was done by injecting CT-26 colon cancer cells intravenously to syngenic mice. The in vitro and in vivo microvessel formation was determined by the tube formation assay and the Matrigel plug assay, respectively. The in vivo anti-tumor effect of THL was determined by a human MDA-MB-231 breast cancer xenograft model. The expression of metalloproteinase (MMP)-2, MMP-9, and urokinase plasminogen activator (uPA) was measured by gelatin zymography. The expression of HIF-1α and the phosphorylation of ERK1/2 were determined by Western blot.

Results

THL inhibited the migration and invasion ability of various cancer cells in vitro, decreased the secretion of MMP-2, MMP-9, and uPA and the activity of ERK1/2 in cancer cells, and suppressed pulmonary metastasis of CT-26 cancer cells in syngenic mice. Moreover, THL inhibited the migration, invasion, and tube formation of endothelial cells in vitro, decreased the secretion of MMP-2 and uPA in endothelial cells, and suppressed neovascularization in Matrigel plugs in mice. Besides its inhibitory effect on endothelial cells, THL inhibited hypoxia-induced HIF-1α and vascular endothelial growth factor-A expression in cancer cells. Finally, our results show that THL inhibited the growth of human MDA-MB-231 breast cancer xenografts in NOD-SCID mice. This suppression of tumor growth was associated with decreased microvessel formation and increased apoptosis caused by THL.

Conclusion

Our data demonstrate that THL had broad-spectra anti-cancer activities and merits further evaluation for its use in cancer therapy.

Final report on the safety assessment of Glycyrrhetinic Acid, Potassium Glycyrrhetinate, Disodium Succinoyl Glycyrrhetinate, Glyceryl Glycyrrhetinate, Glycyrrhetinyl Stearate, Stearyl Glycyrrhetinate, Glycyrrhizic Acid, Ammonium Glycyrrhizate, Dipotassium Glycyrrhizate, Disodium Glycyrrhizate, Trisodium Glycyrrhizate, Methyl Glycyrrhizate, and Potassium Glycyrrhizinate

Glycyrrhetinic Acid and its salts and esters and Glycyrrhizic Acid and its salts and esters are cosmetic ingredients that function as flavoring agents or skin-conditioning agents - miscellaneous or both. These chemicals may be isolated from licorice plants. Glycyrrhetinc Acid is described as at least 98% pure, with 0.6% 24-OH-Glycyrrhetinic Acid, not more than 20 mu g/g of heavy metals and not more than 2 mu g/g of arsenic. Ammonium Glycyrrhizate has been found to be at least 98% pure and Dipotassium Glycyrrhizate has been found to be at least 95% pure. Glycyrrhetinic Acid is used in cosmetics at concentrations of up to 2%; Stearyl Glycyrrhetinate, up to 1%; Glycyrrhizic Acid, up to 0.1%; Ammonium Glycyrrhizate, up to 5%; Dipotassium Glycyrrhizate, up to 1%; and Potassium Glycyrretinate, up to 1%. Although Glycyrrhizic Acid is poorly absorbed by the intestinal tract, it may be hydrolyzed to Glycyrrhetinic Acid by a beta -glucuronidase produced by intestinal bacteria. Glycyrrhetinic Acid and Glycyrrhizic Acid bind to rat and human albumin, but do not absorb well into tissues. Glycyrrhetinic Acid and Glycyrrhizic Acid and metabolites are mostly excreted in the bile, with very little excreted in urine. Dipotassium Glycyrrhizate was undetectable in the receptor chamber when tested for transepidermal permeation through pig skin. Glycyrrhizic Acid increased the dermal penetration of diclofenac sodium in rat skin. Dipotassium Glycyrrhizate increased the intestinal absorption of calcitonin in rats. In humans, Glycyrrhetinic Acid potentiated the effects of hydrocortisone in the skin. Moderate chronic or high acute exposure to Glycyrrhizic Acid, Ammonium Glycyrrhizate, and their metabolites have been demonstrated to cause transient systemic alterations, including increased potassium excretion, sodium and water retention, body weight gain, alkalosis, suppression of the renin-angiotensis-aldosterone system, hypertension, and muscular paralysis; possibly through inhibition of 11beta -hydroxysteroid dehydrogenase-2 (11beta -OHSD2) in the kidney. Glycyrrhetinic Acid and its derivatives block gap junction intracellular communication in a dose-dependent manner in animal and human cells, including epithelial cells, fibroblasts, osteoblasts, hepatocytes, and astrocytes; at high concentrations, it is cytotoxic. Glycyrrhetinic Acid and Glycyrrhizic Acid protect liver tissue from carbon tetrachloride. Glycyrrhizic Acid has been used to treat chronic hepatitis, inhibiting the penetration of the hepatitis A virus into hepatocytes. Glycyrrhetinic Acid and Glycyrrhizic Acid have anti-inflammatory effects in rats and mice. The acute intraperitoneal LD(50) for Glycyrrhetinic Acid in mice was 308 mg/kg and the oral LD(50) was > 610 mg/kg. The oral LD(50) in rats was reported to be 610 mg/kg. Higher LD(50) values were generally reported for salts. Little short-term, subchronic, or chronic toxicity was seen in rats given ammonium, dipotassium, or disodium salts of Glycyrrhizic Acid. Glycyrrhetinic Acid was not irritating to shaved rabbit skin, but was considered slightly irritating in an in vitro test. Glycyrrhetinic Acid inhibited the mutagenic activity of benzo[a]pyrene and inhibited tumor initiation and promotion by other agents in mice. Glycyrrhizic Acid inhibited tumor initiation by another agent, but did not prevent tumor promotion in mice. Glycyrrhizic Acid delayed mortality in mice injected with Erlich ascites tumor cells, but did not reduce the mortality rate. Ammonium Glycyrrhizate was not genotoxic in in vivo and in vitro cytogenetics assays, the dominant lethal assay, an Ames assay, and heritable translocation tests, except for possible increase in dominant lethal mutations in rats given 2000 mg/kg day(-1) in their diet. Disodium Glycyrrhizate was not carcinogenic in mice in a drinking water study at exposure levels up to 12.2 mg/kg day(-1) for 96 weeks. Glycyrrhizate salts produced no reproductive or developmental toxicity in rats, mice, golden hamsters, or Dutch-belted rabbits, except for a dose-dependent increase (at 238.8 and 679.9 mg/kg day(-1)) in sternebral variants in a study using rats. Sedation, hypnosis, hypothermia, and respiratory depression were seen in mice given 1250 mg/kg Glycyrrhetinic Acid intraperitoneally. Rats fed a powdered diet containing up to 4% Ammonium Glycyrrhizate had no treatment related effects in motor function tests, but active avoidance was facilitated at 4%, unaffected at 3%, and depressed at 2%. In a study of 39 healthy volunteers, a no effect level of 2 mg/kg/day was determined for Glycyrrhizic Acid given orally for 8 weeks. Clinical tests in seven normal individuals given oral Ammonium Glycyrrhizate at 6 g/day for 3 days revealed reduced renal and thermal sweat excretion of Na+ and K+, but carbohydrate and protein metabolism were not affected. Glycyrrhetinic Acid at concentrations up to 6% was not a skin irritant or a sensitizer in clinical tests. Neither Glycyrrhizic Acid, Ammonium Glycyrrhizate, nor Dipotassium Glycyrrhizate at 5% were phototoxic agents or photosensitizers. Birth weight and maternal blood pressure were unrelated to the level of consumption of Glycyrrhizic Acid in 1049 Finnish women with infants, but babies whose mother consumed > 500 mg/wk were more likely to be born before 38 weeks. The Cosmetic Ingredient Review (CIR) Expert Panel noted that the ingredients in this safety assessment are not plant extracts, powders, or juices, but rather are specific chemical species that may be isolated from the licorice plant. Because these chemicals may be isolated from plant sources, however, steps should be taken to assure that pesticide and toxic metal residues are below acceptable levels. The Panel advised the industry that total polychlorobiphenyl (PCB)/pesticide contamination should be limited to not more than 40 ppm, with not more than 10 ppm for any specific residue, and that toxic metal levels must not contain more than 3 mg/kg of arsenic (as As), not more than 0.002% heavy metals, and not more than 1 mg/kg of lead (as Pb). Although the Panel noted that Glycyrrhizic Acid is cytotoxic at high doses and ingestion can have physiological effects, there is little acute, short-term, subchronic, or chronic toxicity and it is expected that these ingredients would be poorly absorbed through the skin. These ingredients are not considered to be irritants, sensitizers, phototoxic agents, or photosensitizers at the current maximum concentration of use. Accordingly, the CIR Expert Panel concluded that these ingredients are safe in the current practices of use and concentration. The Panel recognizes that certain ingredients in this group are reportedly used in a given product category, but the concentration of use is not available. For other ingredients in this group, information regarding use concentration for specific product categories is provided, but the number of such products is not known. In still other cases, an ingredient is not in current use, but may be used in the future. Although there are gaps in knowledge about product use, the overall information available on the types of products in which these ingredients are used and at what concentration indicate a pattern of use. Within this overall pattern of use, the Expert Panel considers all ingredients in this group to be safe.

Less-known botanical cosmeceuticals

Complementary and alternative medicine (CAM) has become increasingly popular in the United States during the last 10-15 years. The use of oral and topical supplements falls within this framework. Most oral and topical supplements are based on or include several botanical ingredients, many of which have long histories of traditional or folk medicine usage. Several of the available products derived from botanical sources are touted for their dermatologic benefits. The focus in this discussion will be on a select group of botanical compounds that have been used for dermatologic purposes or show promise for such applications, including: rosemary, polypodium leucotomos, propolis, oatmeal, olive oil, grape seed extract, lavender, mushrooms, and coffeeberry. Other more commonly used products of botanical origin, such as arnica, bromelain, caffeine, chamomile, ferulic acid, feverfew, green tea, licorice, pomegranate, and resveratrol, are also briefly considered.

The chinese herbal medicine Tien-Hsien liquid inhibits cell growth and induces apoptosis in a wide variety of human cancer cells

OBJECTIVE

Tien-Hsien liquid (THL) is a commercially available Chinese herbal mixture that has been used as an anticancer dietary supplement for more than 10 years. We recently showed that THL has strong immunomodulatory effects on peripheral blood mononuclear cells (PBMC) and T cells. To investigate the antitumor activity of THL further, we sought to test whether THL could induce apoptosis in various human cancer cell lines based on the fact that THL contains several components with tumor killing functions.

DESIGN

The growth inhibitory effect of THL on human cervical carcinoma C-33A cells, human lung carcinoma H1299 cells, and human PBMC was assessed by counting viable cells using the trypan blue dye exclusion method. The apoptosis-inducing activity of THL in H1299 cells was assessed by analyzing the cells with four assays: (1) Hoechst 33258 nuclear DNA staining; (2) the terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) assay; (3) the nucleosomal DNA fragment ladder assay; and (4) the sub-G1 cell analysis. The activities of caspase-8, -9, and -3 in H1299 cells treated with or without THL were also measured to elucidate the possible mechanism underlying THL apoptosis-inducing effect. Finally, the apoptotic effect of THL on fifteen human cancer cell lines and normal human cells were analyzed by the TUNEL assay.

RESULTS

THL could induce apoptosis in all human cancer cell lines tested but not in normal human cells. THL treatment of H1299 cancer cells resulted in activation of caspase-8, -9, and -3 and the inhibitors of these caspases could partially block THL-induced apoptosis.

CONCLUSIONS

THL has been used by numerous patients with cancer for many years with no known adverse effect. Our present study showing that THL had a broad-range tumor killing function has provided a molecular basis underlying THL therapeutic activity. Furthermore, because THL had apoptotic effects only on cancer cells but not on normal cells, this selectivity suggests that THL could be a potential cancer therapeutic agent.

Induction of Apoptosis by Korean Medicine Gagam-whanglyun-haedoktang Through Activation of Caspase-3 in Human Leukemia Cell Line, HL-60 Cells

Gagam-whanglyun-haedoktang (GWH) is a newly designed herbal drug formula based on the traditional oriental pharmacological knowledge for the purpose of treating tumorous diseases. Apoptosis is an evolutionarily conserved suicide program residing in cells. In the present study, apoptosis inducing activities of the decocted water extract of GWH were studied. Results of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that GWH had a strong cytotoxic effect on HL-60 cells. The number of live cells was less than 20% after exposure to 1 mg/ml GWH for 48 h. GWH increased cytotoxicity of HL-60 cells in a dose- and time-dependent manner. The percentage of apoptotic cells by flow cytometric analysis of the DNA-stained cells increased to 28%, 31%, and 37% at 24 h and to 37%, 44%, and 81% at 48 h after treatment with 0.01, 0.1, and 1 mg/ml GWH, respectively. DNA fragmentation also occurred in apoptosis and was characterized by a ladder pattern on agarose gel. In addition, GWH increased the secretion of tumor necrosis factor-alpha. GWH-induced apoptosis was accompanied by activation of caspase-3. These results suggest that GWH induces activation of caspase-3 and eventually leads to apoptosis.

PC-SPES: a herbal therapy for the treatment of hormone refractory prostate cancer

In this review the authors consider the commercially available herbal product PC-SPES. This is a combination of eight different herbs marketed for its effects of reducing prostate specific antigen (PSA) levels, improving pain, and enhancing the quality of life of those with hormone refractory prostate cancer. The evidence for these claims does not appear to be as conclusive as reported by the manufactures of this product. There also appears to be a significant risk of deep vein thrombosis (DVT) in those treated with PC-SPES. There have been 116 clinical and laboratory based studies of PC-SPES published to date, but there have been no randomised controlled trials conducted. Many of these studies contain very few patients, thus making the drawing of conclusions difficult. Despite this lack of information, there still remains a large patient group taking this supplement, therefore caution should be advised in the usage of PC-SPES in the treatment of hormone refractory prostate cancer.

Licorice and cancer

Licorice root is one of the oldest and most frequently employed botanicals in Chinese medicine. In the United States, licorice products are most often used as flavoring and sweetening agents in food products. Constituents of licorice include triterpenoids, such as glycyrrhizin and its aglycone glycyrrhizic acid, various polyphenols, and polysaccharides. A number of pharmaceutical effects of licorice are known or suspected (anti-inflammatory, antivirus, antiulcer, anticarcinogenesis, and others). Licorice and its derivatives may protect against carcinogen-induced DNA damage and may be suppressive agents as well. Glycyrrhizic acid is an inhibitor of lipoxygenase and cyclooxygenase, inhibits protein kinase C, and downregulates the epidermal growth factor receptor. Licorice polyphenols induce apoptosis in cancer cells. These and other activities of licorice are reviewed, and a rationale is suggested for combinations of agents in preventive clinical trials.

Inhibitory effect of herbal remedies on 12-O-tetradecanoylphorbol-13-acetate-promoted Epstein-Barr virus early antigen activation

For the past several years we have been evaluating natural products as potential cancer chemopreventive agents in a short term in vitro assay involving Epstein--Barr virus early antigen (EBV-EA) activation in Raji cells promoted by phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA). Because of the current interest in the use of herbal remedies, we considered examining them for their cancer chemopreventive activities, using their extracts with a view to uncovering such benefits (if any) these remedies might possess. Thirty-six extracts of 32 herbs belonging to 27 families in use as herbal remedies including those of gingko, black cohosh, echinacea, kava-kava, saw palmetto, turmeric, angelica, wild yam, cat's claw, passion flower, muira puama, feverfew, blueberry, chasteberry, licorice, nettle, golden seal, pygeum, ginger, valerian and hops were prepared and evaluated. Turmeric at a concentration of 10 microg x ml (-1)exhibited the most potent anti-EBV-EA activity, which is ten times more than passionflower, that is next in the order of activity. At the concentration level of 100 microg ml (-1), several of the herbal remedies tested inhibited the EBV-EA in Raji cells exposed to the tumor promoter TPA (32 pM) by more than 90%. We also report for the first time the activities of 16 new medicinal plants as potential cancer chemopreventive agents. Since inhibitors of EBV-EA promoted by TPA in vitro have been shown to be effective anti-tumor promoting agents in laboratory animal models, our results indicate new and potential applications of these herbal remedies as cancer chemopreventive agents since they are already in clinical use in the human population.

Herbal therapy PC-SPES: in vitro effects and evaluation of its efficacy in 69 patients with prostate cancer

PURPOSE

We investigate the potential use of the phytotherapeutic PC-SPES to treat human prostate cancer, and evaluate its in vivo and in vitro activity, and clinical efficacy.

MATERIALS AND METHODS

PC-SPES was evaluated for its ability to induce apoptosis on prostate cancer cell lines LNCaP, PC3 and DU145. The effect of oral PC-SPES on growth of PC3 tumors present in male immunodeficient mice was studied. A total of 30 male nude mice were divided in 5 groups. In groups 1 control and 2 full dose therapy was started the same day of the tumor injection. In groups 3 control, 4 half dose and 5 full dose PC-SPES therapy was initiated 1 week after tumor injection. A total of 69 patients with prostate cancer were treated with 3 capsules of 320 mg. PC-SPES daily. Serum prostate specific antigen (PSA) responses and side effects were evaluated.

RESULTS

All of the cultured prostate cancer cell lines had a significant dose dependent induction of apoptosis following exposure to an alcoholic PC-SPES extract. Immunodeficient mice xenografted with the PC3 cell line had reduced tumor volume compared with sham treated controls when they were treated with a PC-SPES extract from the time of tumor cell implantation (931 +/- 89 versus 1,424 +/- 685 mm.3, p not significant) but not when the treatment was begun 1 week after tumor cell implantation. The testis, prostate, bladder and seminal vesicles of the treated mice were significantly reduced in weight compared with the sham treated animals. Of the patients with prostate cancer 82% had decreased serum PSA 2 months, 78% 6 months and 88% 12 months after treatment with PC-SPES. Side effects in the treated patient population included nipple tenderness in 42% and phlebitis requiring heparinization in 2%.

CONCLUSIONS

An extract of the phytotherapeutic agent PC-SPES proved to be active in inducing apoptosis of hormone sensitive and insensitive prostate cancer cells in vitro, and in suppressing the growth rate of a hormone insensitive prostate cancer cell line in vivo. The overwhelming majority of patients with prostate cancer treated with the agent experienced a decrease in serum PSA but also demonstrated a side effect profile comparable to estrogen treatment.

Antimutagenic effect of fruit and vegetable ethanolic extracts against N-nitrosamines evaluated by the Ames test

The inhibitory effect of nine fruit and vegetable ethanolic extracts against the mutagenicity of N-nitrosodimethylamine (NDMA), N-nitrosopyrrolidine (NPYR), N-nitrosodibutylamine (NDBA), and N-nitrosopiperidine (NPIP) was evaluated by means of the Ames test. Licorice ethanolic extract was the only one that showed an inhibitory effect (ranging from moderate to strong) against mutagenicity of all N-nitrosamines tested. This ethanolic extract showed the greatest inhibition effect against NPIP (72%), NDMA (45%), and NPYR (39%). The greatest inhibition effect (51%) of the mutagenicity of NDBA was shown by kiwi ethanolic extract. Vegetable and fruit ethanolic extracts that exhibited an antimutagenic effect (at the range 50-2000 microg/plate), in decreasing order, against NDMA and NPYR were as follows: licorice > kiwi > carrot and licorice > broccoli > pineapple > kiwi, respectively. Decreasing orders against NDBA and NPIP were, respectively, kiwi > onion > licorice = garlic > green pepper > carrot and licorice > garlic > pineapple > carrot.

Preventive effects of Glycyrrhizae radix extract on estrogen-related endometrial carcinogenesis in mice

Short- and long-term experiments were conducted to examine the effects of Glycyrrhizae radix (Gl radix) extract on mouse endometrial carcinogenesis. Gl radix treatment (2 weeks) decreased the levels of c-fos/jun mRNA and the corresponding oncoproteins induced by estradiol-17 beta (E2) in castrated mice uteri, as determined by reverse transcription-polymerase chain reaction and Southern blot analysis, and immunohistochemical methods, respectively. For the long-term assays, 98 female ICR mice were given N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body wt.) and normal saline (as controls) into their left and right uterine corpora, respectively. They were divided into four groups as follows: group 1 was given 0.625% Gl radix- and 5 ppm E2-containing diet; group 2, 5 ppm E2-containing diet; group 3, 0.625% Gl radix-containing diet; and group 4, the basal diet alone. Gl radix treatment significantly decreased uterine weights and the incidences of uterine endometrial atypical hyperplastic and malignant lesions. It is suggested that Gl radix has inhibitory effects on E2-related endometrial carcinogenesis in mice, through suppression of estrogen-induced c-fos/jun-expressions.

Studies on mechanism of action of glycyrrhizin against hepatitis A virus replication in vitro

Glycyrrhizin (GL) achieved a concentration-dependent inhibition of the replication of hepatitis A virus (HAV) in PLC/PRF/5 cells. GL has been shown to inhibit an early stage of the HAV replication. GL was not virucidal and had no measurable effect on the adsorption of [3H]uridine-labelled virions to cells. GL inhibited HAV penetration of the plasma membrane as measured by the amount of infective virus no longer neutralizable by specific antibody over time.

(-)-Epigallocatechin-3-gallate in Camellia sinensis leaves from Himalayan region of Sikkim: inhibitory effects against biochemical events and tumor initiation in Sencar mouse skin

Recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. It has been suggested that (-)-epigallocatechin-3-gallate (EGCG), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. During the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the Himalayan region of Sikkim, India that was rich in EGCG. EGCG was isolated from this tea product, and its inhibitory effects were evaluated against the binding of topically applied 3H-labeled polycyclic aromatic hydrocarbons (PAHs) to epidermal DNA and 12-O-tetradecanoylphorbol-13-acetate (TPA) caused induction of epidermal ornithine decarboxylase (ODC) activity in Sencar mice, the short-term markers of tumor initiation and tumor promotion, respectively. Preapplication of EGCG resulted in significant inhibition (p less than 0.05) in the binding of [3H]PAH to epidermal DNA. Similarly, the topical application of EGCG resulted in significant inhibition (p less than 0.005) in TPA-caused induction of epidermal ODC activity. In further studies, we assessed the anti-skin tumor-initiating effect of EGCG in Sencar mice in an initiation-promotion protocol. The application of EGCG before challenge with 7,12-dimethylbenz[a]anthracene as tumor initiator resulted in significant reduction both in percentage of mice with tumors and number of tumors per mouse compared with a non-EGCG-pretreated group of animals. The results of the present study suggest that the green tea preparation from Sikkim may be a good source for the isolation of EGCG and that this compound may have significant potential as a cancer chemopreventive agent.