Biological activities of phenolic compounds and triterpenoids from the galls of Terminalia chebula

Simultaneous quantitative analysis and in vitro anti-arthritic effects of five polyphenols from Terminalia chebula

Background: The fruit of Terminalia chebula has been widely used for a thousand years for treating diarrhea, ulcers, and arthritic diseases in Asian countries. However, the active components of this Traditional Chinese medicine and their mechanisms remain unclear, necessitating further investigation. Objectives: To perform simultaneous quantitative analysis of five polyphenols in T. chebula and evaluate their anti-arthritic effects including antioxidant and anti-inflammatory activity in vitro. Materials and methods: Water, 50% water-ethanol, and pure ethanol were used as extract solvents. Quantitative analysis of gallic acid, corilagin, chebulanin, chebulagic acid, and ellagic acid in the three extracts was performed using high-performance liquid chromatography (HPLC). Antioxidant activity was assessed by the 2,2-diphenylpicrylhydrazyl (DPPH) radical-scavenging assay, and anti-inflammatory activity was evaluated by detecting interleukin (IL)-6 and IL-8 expression in IL-1β-stimulated MH7A cells. Results: The 50% water-ethanol solvent was the optimal solvent yielding the highest total polyphenol content, and the concentrations of chebulanin and chebulagic acid were much higher than those of gallic acid, corilagin, and ellagic acid in the extracts. The DPPH radical-scavenging assay showed that gallic acid and ellagic acid were the strongest antioxidative components, while the other three components showed comparable antioxidative activity. As for the anti-inflammatory effect, chebulanin and chebulagic acid significantly inhibited IL-6 and IL-8 expression at all three concentrations; corilagin and ellagic acid significantly inhibited IL-6 and IL-8 expression at high concentration; and gallic acid could not inhibit IL-8 expression and showed weak inhibition of IL-6 expression in IL-1β-stimulated MH7A cells. Principal component analysis indicated that chebulanin and chebulagic acid were the main components responsible for the anti-arthritic effects of T. chebula. Conclusion: Our findings highlight the potential anti-arthritic role of chebulanin and chebulagic acid from T. chebula.

A comprehensive review on the diverse pharmacological perspectives of Terminalia chebula Retz

Terminalia chebula Retz, commonly known as 'Haritaki/Myrobalan,' has been utilised as a traditional medicine for a long time. It has been extensively exercised in various indigenous medicine practices like Unani, Tibb, Ayurveda, and Siddha to remedy human ailments such as bleeding, carminative, dysentery, liver tonic, digestive, antidiarrheal, analgesic, anthelmintic, antibacterial and helpful in skin disorders. Studies on the pharmacological effects of T. chebula and its phytoconstituents documented between January, 1996 and December, 2021 were explored using various electronic databases. During the time mentioned above, several laboratory approaches revealed the biological properties of T. chebula, including antioxidative, antiproliferative, anti-microbial, proapoptotic, anti-diabetic, anti-ageing, hepatoprotective, anti-inflammatory, and antiepileptic. It is also beneficial in glucose and lipid metabolism and prevents atherogenesis and endothelial dysfunction. Different parts of T. chebula such as fruits, seeds, galls, barks extracted with various solvent systems (aqueous, ethanol, methanol, chloroform, ethyl-acetate) revealed major bioactive compounds like chebulic acid, chebulinic acid, and chebulaginic acid, which in turn proved to have valuable pharmacological properties through broad scientific investigations. There is a common link between chebulagic acid and chebulanin with its antioxidant property, antiaging activity, antiinflammatory, antidiabetic activity, and cardioprotective activity. The actions may be through neutralizing the free radicals responsible for producing tissue damage alongside interconnecting many other diseases. The current review summarises the scientifically documented literature on pharmacological potentials and chemical compositions of T. chebula, which is expected to investigate further studies on this subject.

Anti-viral triterpenes: a review

Triterpenes are naturally occurring derivatives biosynthesized following the isoprene rule of Ruzicka. The triterpenes have been reported to possess a wide range of therapeutic applications including anti-viral properties. In this review, the recent studies (2010-2020) concerning the anti-viral activities of triterpenes have been summarized. The structure activity relationship studies have been described as well as brief biosynthesis of these triterpenes is discussed.

Ayurveda Rasayana as antivirals and immunomodulators: potential applications in COVID-19

Coronavirus disease (COVID-19) has been declared as a pandemic by the World Health Organization with rapid spread across 216 countries. COVID-19 pandemic has left its imprints on various health systems globally and caused immense social and economic disruptions. The scientific community across the globe is in a quest for digging the effective treatment for COVID-19 and exploring potential leads from traditional systems of healthcare across the world too. Ayurveda (Indian traditional system of medicine) has a comprehensive aspect of immunity through Rasayana which is a rejuvenation therapy. Here we attempt to generate the potential leads based on the classical text from Ayurveda in general and Rasayana in particular to develop effective antiviral and/or immunomodulator for potential or adjunct therapy in SARS-CoV-2. The Rasayana acts not only by resisting body to restrain or withstand the strength, severity or progression of a disease but also by promoting power of the body to prevent the manifestation of a disease. These Rasayana herbs are common in practice as immunomodulator, antiviral and protectives. The studies on Rasayana can provide an insight into the future course of research for the plausible development of effective management of COVID-19 by the utilization and development of various traditional systems of healthcare. Keeping in view the current pandemic situation, there is an urgent need of developing potential medicines. This study proposes certain prominent medicinal plants which may be further studied for drug development process and also in clinical setup under repurposing of these herbs.

Effects of hydroethanolic extracts of Terminalia chebula and Thymbra spicata on ram fresh semen under normal and oxidative stress conditions

The objective of this study was to evaluate protective effects of hydroethanolic extracts of Terminalia chebula and Thymbra spicata on viability, lipid peroxidation (LPO) and DNA integrity of ram fresh semen under normal and oxidative stress (OS) conditions. Antioxidant activities of different concentrations of Terminalia chebula and Thymbra spicata extracts were evaluated with DPPH assay. Semen samples were taken from three fertile adult rams. After diluting semen with Tris-base extender, different concentrations of Terminalia chebula and Thymbra spicata (30, 300, and 3000 μg/ml) extracts were used under normal and induced OS conditions. The group not receiving any supplements was considered as control group. A total of 50 μM hydrogen peroxide was used to induce OS. MTT solution was added to each of treatment groups which were kept in an incubator at 37°C for 2 h. After incubation, readings were obtained by ELISA reader. DNA integrity and LPO were determined with acridine orange (AO) staining and malondialdehyde (MDA) assay. Higher concentrations of Terminalia chebula and Thymbra spicata extracts preserved viability and DNA integrity while reducing MDA concentrations compared to other treatment groups. Also, under induced OS, higher concentrations of both extracts reduced detrimental effects of H₂ O₂ . In conclusion, it seems that addition of Terminalia chebula and Thymbra spicata extracts can reduce induced OS in spermatozoa.

Inhibition of the intestinal postprandial glucose transport by gallic acid and gallic acid derivatives

Inhibition of glucose uptake in the intestine through sodium-dependent glucose transporter 1 (SGLT1) or glucose transporter 2 (GLUT2) may be beneficial in controlling postprandial blood glucose levels. Gallic acid and ten of its derivatives were identified in the active fractions of Terminalia chebula Retz. fructus immaturus, a popular edible plant fruit which has previously been associated with the inhibition of glucose uptake. Gallic acid derivatives (methyl gallate, ethyl gallate, pentyl gallate, 3,4,6-tri-O-galloyl-β-d-glucose, and corilagin) showed good glucose transport inhibition with inhibitory rates of 72.1 ± 1.6%, 71.5 ± 1.4%, 79.9 ± 1.2%, 44.7 ± 1.2%, and 75.0 ± 0.7% at 5 mM d-glucose and/or 56.3 ± 2.3, 52.1 ± 3.2%, 70.2 ± 1.7%, 15.6 ± 1.6%, and 37.1 ± 0.8% at 25 mM d-glucose. However, only 3,4,6-tri-O-galloyl-β-d-glucose and corilagin were confirmed GLUT2-specific inhibitors. Whilst some tea flavonoids demonstrated minimal glucose transport inhibition, their gallic acid derivatives strongly inhibited transport effect with GLUT2 specificity. This suggests that gallic acid structures are crucial for glucose transport inhibition. Plants, such as T. chebula, which contain high levels of gallic acid and its derivatives, show promise as natural functional ingredients for inclusion in foods and drinks designed to control postprandial glucose levels.

Chebulanin exerts its anti-inflammatory and anti-arthritic effects via inhibiting NF-κB and MAPK activation in collagen-induced arthritis mice

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial inflammation and progressive joint destruction. Chebulanin is a natural polyphenol acid isolated from the traditional Tibetan medicine Terminalia chebula Retz that has previously been reported to possess anti-inflammatory properties. The present study aimed to investigate the anti-inflammatory and anti-arthritic effects of chebulanin and explore its underlying mechanisms in vivo and in vitro using a collagen-induced arthritis (CIA) mouse model and lipopolysaccharide (LPS) stimulated RAW264.7 cell inflammation model. Arthritis severity scores were assessed twice weekly; the levels of cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in serum were detected using enzyme-linked immunosorbent assay kits; histopathological assessment was performed using micro computed tomography and hematoxylin and eosin staining. Activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were assessed using western blotting. The inhibition of translocation of cytosolic p38 and p65 into the nucleus was observed using immunofluorescence staining and western blotting in vitro. Chebulanin significantly suppressed the progression and development of RA in CIA mice by decreasing the arthritis severity scores, attenuating paw swelling and joint destruction, and reducing the levels of IL-6 and TNF-α significantly (p < 0.05). Furthermore, chebulanin reduced the levels of excised phosphorylated (p)-p38, phosphorylated-c-JUN N-terminal kinase (p-JNK), p-p65 and phosphorylated NF-κB inhibitor alpha (p-IκBα) in CIA mice, but did not affect the level of phosphorylated extracellular-signal-regulated kinase (ERK). In addition, chebulanin could inhibit the nuclear translocation of p38 and p65 in LPS-stimulated macrophages in dose-dependent manner. In conclusion, this study demonstrated that chebulanin exerts anti-inflammatory and anti-arthritic effects by inhibiting the activation of NF-κB and MAPK signaling pathways.

Terminalia albida treatment improves survival in experimental cerebral malaria through reactive oxygen species scavenging and anti-inflammatory properties

Background

The development of Plasmodium resistance to the last effective anti-malarial drugs necessitates the urgent development of new anti-malarial therapeutic strategies. To this end, plants are an important source of new molecules. The objective of this study was to evaluate the anti-malarial effects of Terminalia albida, a plant used in Guinean traditional medicine, as well as its anti-inflammatory and antioxidant properties, which may be useful in treating cases of severe malaria.

Methods

In vitro antiplasmodial activity was evaluated on a chloroquine-resistant strain of Plasmodium falciparum (K-1). In vivo efficacy of the plant extract was measured in the experimental cerebral malaria model based on Plasmodium berghei (strain ANKA) infection. Mice brains were harvested on Day 7–8 post-infection, and T cells recruitment to the brain, expression levels of pro- and anti-inflammatory markers were measured by flow cytometry, RT-qPCR and ELISA. Non-malarial in vitro models of inflammation and oxidative response were used to confirm Terminalia albida effects. Constituents of Terminalia albida extract were characterized by ultra‐high performance liquid chromatography coupled with high resolution mass spectrometry. Top ranked compounds were putatively identified using plant databases and in silico fragmentation patterns.

Results

In vitro antiplasmodial activity of Terminalia albida was confirmed with an IC50 of 1.5 μg/mL. In vivo, Terminalia albida treatment greatly increased survival rates in P. berghei-infected mice. Treated mice were all alive until Day 12, and the survival rate was 50% on Day 20. Terminalia albida treatment also significantly decreased parasitaemia by 100% on Day 4 and 89% on Day 7 post-infection. In vivo anti-malarial activity was related to anti-inflammatory properties, as Terminalia albida treatment decreased T lymphocyte recruitment and expression of pro-inflammatory markers in brains of treated mice. These properties were confirmed in vitro in the non-malarial model. In vitro, Terminalia albida also demonstrated a remarkable dose-dependent neutralization activity of reactive oxygen species. Twelve compounds were putatively identified in Terminalia albida stem bark. Among them, several molecules already identified may be responsible for the different biological activities observed, especially tannins and triterpenoids.

Conclusion

The traditional use of Terminalia albida in the treatment of malaria was validated through the combination of in vitro and in vivo studies.

A Comprehensive Review of the Structure Elucidation of Tannins from Terminalia Linn

OBJECTIVES

Tannins with complex structures are important plant resources, which are abundant in the genus Terminalia. Various Terminalia species have been playing an important role in traditional medicine system. A systematic scoping review of Terminalia Linn. research literature for tannins was conducted to summarize the structures of tannins and analysis fragmentation pathway characteristics, which could provide references for the structural analysis of tannins from Terminalia Linn.

METHODS

After an update of the literature search up to September 2018, the terms of Terminalia in all publications were analyzed. Electronic searches were conducted in scifinder and PubMed, and the information from 197 articles in all with regard to the tannin structure study was extracted.

RESULTS

The compounds of 82 tannins from the genus Terminalia were reviewed. According to the structural differences, they can be divided into three categories, hydrolysable tannins, condensed tannins, and complex tannins, respectively. The fragmentation pathways of 46 identified tannins were analyzed, and the fragmentation rules of tannins were speculated according to different types.

CONCLUSION

This review has attracted attention to the active substances in this species such as the tannins summarized in further study. How to improve the extraction and purification technology of tannins from genus Terminalia is an urgent problem to be solved.

Melanogenesis-Inhibitory and Cytotoxic Activities of Triterpene Glycoside Constituents from the Bark of Albizia procera

Five oleanane-type triterpene glycosides including three new ones, proceraosides E-G (1-3), were isolated from a MeOH-soluble extract of Albizia procera bark. The structures of 1-3 were determined by use of NMR spectra, HRESIMS, and chemical methods. Compounds 1-5 exhibited inhibitory activities against the proliferation of the A549, SKBR3, AZ521, and HL60 human cancer cell lines (IC₅₀ 0.28-1.8 μM). Additionally, the apoptosis-inducing activity of compound 2 was evaluated by Hoechst 33342 staining and flow cytometry, while the effects of 2 on the activation of caspases-9, -8, and -3 in HL60 cells were revealed by Western blot analysis.

Terminalia laxiflora and Terminalia brownii contain a broad spectrum of antimycobacterial compounds including ellagitannins, ellagic acid derivatives, triterpenes, fatty acids and fatty alcohols

ETHNOPHARMACOLOGICAL RELEVANCE

Terminalia laxiflora Engl. & Diels, (Sudanese Arabic name: Darout الدروت) and Terminalia brownii Fresen (Sudanese Arabic name: Alshaf ألشاف) (Combretaceae) are used in Sudanese traditional folk medicine and in other African countries for treatment of infectious diseases, TB and its symptoms, such as cough, bronchitis and chest pain.

AIM OF STUDY

Because of the frequent use of T. laxiflora and T. brownii in African traditional medicine and due to the absence of studies regarding their antimycobacterial potential there was a need to screen extracts of T. laxiflora and T. brownii for their growth inhibitory potential and to study the chemical composition and compounds in growth inhibitory extracts.

MATERIALS AND METHODS

The plant species were collected in Sudan (Blue Nile Forest, Ed Damazin Forestry areas) and selected according to their uses in traditional medicine for the treatment of bacterial infections, including TB. Eighty extracts and fractions of the stem bark, stem wood, roots, leaves and fruits of T. laxiflora and T. brownii and nine pure compounds present in the active extracts were screened against Mycobacterium smegmatis ATCC 14468 using agar diffusion and microplate dilution methods. Inhibition zones and MIC values were estimated and compared to rifampicin. HPLC-UV/DAD, GC/MS and UHPLC/Q-TOF MS were employed to identify the compounds in the growth inhibitory extracts.

RESULTS

The roots of T. laxiflora and T. brownii gave the best antimycobacterial effects (IZ 22-27 mm) against Mycobacterium smegmatis. The lowest MIC of 625 µg/ml was observed for an acetone extract of the root of T. laxiflora followed by methanol and ethyl acetate extracts, both giving MIC values of 1250 µg/ml. Sephadex LH-20 column chromatography purification of T. brownii roots resulted in low MIC values of 62.5 µg/ml and 125 µg/ml for acetone and ethanol fractions, respectively, compared to 5000 µg/ml for the crude methanol extract. Methyl (S)-flavogallonate is suggested to be the main active compound in the Sephadex LH- 20 acetone fraction, while ellagic acid xyloside and methyl ellagic acid xyloside are suggested to give good antimycobacterial activity in the Sephadex LH-20 ethanol fraction. RP-18 TLC purifications of an ethyl acetate extract of T. laxiflora roots resulted in the enrichment of punicalagin in one of the fractions (Fr5). This fraction gave a five times smaller MIC (500 µg/ml) than the crude ethyl acetate extract (2500 µg/ml) and this improved activity is suggested to be mostly due to punicalagin. 1,18-octadec-9-ene-dioate, stigmast-4-en-3-one, 5α-stigmastan-3,6-dione, triacontanol, sitostenone and β-sitosterol were found in antimycobacterial hexane extracts of the stem bark of both studied species. Of these compounds, 1,18-octadec-9-ene-dioate, stigmast-4-en-3-one, 5α-stigmastan-3,6-dione, triacontanol, sitostenone have not been previously identified in T. brownii and T. laxiflora. Moreover, both plant species contained friedelin, betulinic acid, β-amyrine and two unknown oleanane-type triterpenoids. Of the listed compounds, friedelin, triacontanol and sitostenone gave a MIC of 250 µg/ml against M. smegmatis, whereas stigmasterol and β-sitosterol gave MIC values of 500 µg/ml.

CONCLUSIONS

Our results show that T. laxiflora and T. brownii contain antimycobacterial compounds of diverse polarities and support the traditional uses of various parts of T. laxiflora and T.brownii as decoctions for treatment of tuberculosis. Further investigations are warranted to explore additional (new) antimycobacterial compounds in the active extracts of T. laxiflora and T. brownii.

Brassica rapa hairy root extracts promote skin depigmentation by modulating melanin production and distribution

BACKGROUND

Skin whitening products, used for ages by Asian people for cultural and esthetic purposes, are very popular nowadays in Western countries as well, where the need to inhibit skin spots after sun exposure has become not only a cosmetic but also a health-related issue. Thus, the development of effective and safe depigmenting agents derived from natural products gets continuous attention by cosmetic brands and consumers.

OBJECTIVES

The aim of this study was to determine the effects of two preparations, obtained from the hairy root cultures of the species Brassica rapa, on melanogenesis and the expression of the extracellular matrix proteins involved in a correct pigment distribution.

METHODS

The two preparations, obtained by water-ethanol extraction and by digestion of cell-wall glycoproteins of the root cells, were chemically characterized and tested on skin cell cultures and on human skin explants to investigate on their dermatological activities.

RESULTS

Both the extracts were able to decrease melanin synthesis pathway in melanocytes and modulate the expression of genes involved in melanin distribution. One of the extracts was also effective in inducing the expression of laminin-5 and collagen IV, involved into the maintenance of tissue integrity. The two extracts, when tested together on human skin explants, demonstrated a good synergic hypopigmenting activity.

CONCLUSIONS

Taken together, the results indicate that the extracts from B. rapa root cultures can be employed as cosmetic active ingredients in skin whitening products and as potential therapeutic agents for treating pigmentation disorders.

Potential cancer chemopreventive and anticancer constituents from the fruits of Ficus hispida L.f. (Moraceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Ficus hispida L.f. (Moraceae) has been used as alternative for traditional medicine in the treatment of various ailments including cancer-cure. The aim of this study was to evaluate the cancer chemopreventive and anticancer activities of crude extracts of F. hispida, with the objective to screen the inhibition of Epstein-Barr virus early antigen, and cytotoxic active components, and provide foundation for potential applications of this promising medical plant.

MATERIALS AND METHODS

Compounds were isolated from the MeOH extract of F. hispida fruits, and their structure elucidation was performed on the basis of extensive spectroscopic analysis. The isolated compounds were evaluated for their inhibitory activities against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, and cytotoxic activities against human cancer cell lines (HL60, A549, SKBR3, KB, Hela, HT29, and HepG2) and a normal cell (LO2) using MTT method. For the compound with potent cytotoxic activity, its apoptosis inducing activity was evaluated by the observation of ROS generation level expression, and membrane phospholipid exposure and DNA fragmentation in flow cytometry. The mechanisms of the apoptosis induction were analyzed by Western blotting.

RESULTS

Nineteen compounds, 1-19, including two new isoflavones, 3'-formyl-5,7-dihydroxy-4'-methoxyisoflavone (2) and 5,7-dihydroxy-4'-methoxy-3'- (3-methyl-2-hydroxybuten-3-yl)isoflavone (3), were isolated from the MeOH extract of F. hispida fruits. Five compounds, isowigtheone hydrate (1), 2, 3, 9, and 19, showed potent inhibitory effects on EBV-EA induction with IC₅₀ values in the range of 271-340 molar ratio 32 pmol^-1 TPA. In addition, five phenolic compounds, 1-3, 10, and 13, exhibited cytotoxic activity against two or more cell lines (IC₅₀ 2.5-95.8μM), as well as compounds 1 and 3 were also displayed high selectivity for LO2/HepG2 (SI 23.5 and 11.8, respectively), while the compound 1-induced ROS generation leads to activated caspases-3, -8, and -9 apoptotic process in HL60 cells.

CONCLUSION

This study has established that the MeOH extract of F. hispida fruits contains isoflavones, coumarins, caffeoylquinic acids, along with other compounds including phenolics and steroid glucoside as active principles, and has demonstrated that the chemical constituents of F. hispida may be valuable as potential chemopreventive and anticancer agents.

Can highly cited herbs in ancient Traditional Chinese medicine formulas and modern publications predict therapeutic targets for diabetes mellitus?

ETHNOPHARMACOLOGICAL RELEVANCE

The prevalence of diabetes among all age groups worldwide was estimated to be more than 382 million in 2013. Traditional Chinese medicine (TCM) has been practiced for thousands of years, and substantial valuable experience and prescriptions have been accumulated in the TCM system for the treatment of diabetes. In recent decades, a large amount of experimental and clinical data has been published on the use of herbal medicines related to these ancient TCM prescriptions.

AIM OF THE STUDY

This study aimed to discover a method for the investigation of potential antidiabetic herbs from the large amount of data in ancient TCM formulas and modern publications and to verify this method through an in vitro bioactivity study.

MATERIALS AND METHODS

In our review, the most frequently cited TCM herbs were selected as potential antidiabetic herb candidates on the basis of TCM philosophical theory (ancient TCM formulas) and Western medicine philosophical theory (modern publications). The ethanol and aqueous extracts of the selected herbs were screened for their α-glucosidase inhibitory, glucose-stimulated insulin secretion (GSIS), and intestinal glucose transport inhibitory effects.

RESULTS

Twelve herbs [Terminalia chebula Retz., fructus immaturus, dried; Poria cocos (Schw) Wolf., sclerotium, dried; Zea mays L., stigma, dried; Pueraria lobata (Willd.) Ohwi, radix, dried; Cucurbita moschata (Duch. ex Lam.) Duch. ex Poiret, fructus, dried; Lycium barbarum L., fructus, dried; Glycine max (L.) Merr., semen, fermented; Glycyrrhiza uralensis Fisch., radix and rhizoma, dried; Dioscorea opposita Thunb., rhizoma, dried; Morus alba L., folium, dried, Morus alba L., fructus, dried; and Polygonatum odoratum (Mill.) Druce, rhizoma, dried] were finally selected as candidates with potential glucose-lowering effects after a review was performed of herbs that are frequently cited in ancient TCM formulas and modern publications. The bioactive study results demonstrated that both the ethanol extracts and crude polysaccharides of M. alba L., fructus, dried, and M. alba L., folium, dried, and the crude polysaccharides of T. chebula Retz., fructus immaturus, dried, exhibited α-glucosidase inhibitory effects. Moreover, the crude polysaccharides of P. cocos (Schw) Wolf., sclerotium, dried; Z. mays L., stigma, dried; and T. chebula Retz., fructus immaturus, dried, exhibited favorable GSIS effects, and the ethanol extracts of P. odoratum (Mill.) Druce, rhizoma, dried; T. chebula Retz., fructus immaturus, dried; and G. uralensis Fisch., radix and rhizoma, dried, significantly decreased glucose transport across the cell monolayer.

CONCLUSIONS

Our review and the preliminary bioactive study revealed that 10 of the 12 recommended edible TCM herbs had favorable antidiabetic effects, demonstrating that TCM herbs with a high prescription and publication frequency may provide insights into the potential therapeutic targets of diabetes mellitus and may aid in the discovery of effective compounds complementary to currently used medicines. Such a literature and medicine review is a useful method of exploring potential antidiabetic herbs by using the wealth of information in ancient TCM formulas and modern publications.

Triterpenoids from Ganoderma lucidum inhibit the activation of EBV antigens as telomerase inhibitors

Nasopharyngeal carcinoma (NPC) is a malignant disease that threatens the health of humans. To find effective agents for the inhibition of Epstein-Barr virus (EBV) infection, which is associated with NPC, a phytochemical investigation of Ganoderma lucidum was carried out in the present study. Five triterpenoids were identified, including ganoderic acid A (compound 1), ganoderic acid B (compound 2), ganoderol B (compound 3), ganodermanontriol (compound 4), and ganodermanondiol (compound 5), on the basis of spectroscopic analysis. An inhibition of EBV antigens activation assay was implemented to elucidate the triterpenoids from G. lucidum and potentially prevent NPC. All the triterpenoids showed significant inhibitory effects on both EBV EA and CA activation at 16 nmol. At 3.2 nmol, all the compounds moderately inhibited the activation of the two antigens. The activity of telomerase was inhibited by these triterpenoids at 10 µM. Molecular docking demonstrated that compound 1 was able to inhibit telomerase as a ligand. In addition, the physicochemical properties of these compounds were calculated to elucidate their drug-like properties. These results provided evidence for the application of these triterpenoids and whole G. lucidum in the treatment of NPC.

Use of ethanol extracts of Terminalia chebula to prevent periodontal disease induced by dental plaque bacteria

BACKGROUND

The fruit of the Terminalia chebula tree has been widely used for the treatment of various disorders. Its anti-diabetic, anti-mutagenic, anti-oxidant, anti-bacterial, anti-fungal, and anti-viral effects have been studied. Dental plaque bacteria (DPB) are intimately associated with gingivitis and periodontitis. In the quest for materials that will prove useful in the treatment and prevention of periodontal disease, we investigated the preventive effects of an ethanol extract of Terminalia chebula (EETC) on DPB-induced inflammation and bone resorption.

METHODS

The anti-bacterial effect of EETC was analyzed using the disc diffusion method. The anti-inflammatory effect of EETC was determined by molecular biological analysis of the DPB-mediated culture cells. Prevention of osteoclastic bone resorption by EETC was explored using osteoclast formation and pit formation assays.

RESULTS

EETC suppressed the growth of oral bacteria and reduced the induction of inflammatory cytokines and proteases, abolishing the expression of PGE2 and COX-2 and inhibiting matrix damage. By stimulating the DPB-derived lipopolysaccharides, EETC inhibited both osteoclast formation in osteoclast precursors and RANKL expression in osteoblasts, thereby contributing to the prevention of bone resorption.

CONCLUSIONS

EETC may be a beneficial supplement to help prevent DPB-mediated periodontal disease.

Order of aging of major human organs or systems and evaluation of health status based on aging

To determine the functional age of an individual, a quantitative system for the assessment of aging status was developed in the present study. A total of 1579 subjects were selected randomly from patients undergoing physical examination. The index of organic mild impairment (IOMI) and IOMI corrected for age (COMI) were calculated. By receiver operating characteristic (ROC) curve analysis of the IOMIs of younger and elderly subjects, a cutoff value for COMI of 30% was obtained. About 95% of <30-year-old subjects were healthy. These data suggest that organs and systems reflect the aging status of an individual and may be a useful tool for evaluating health status.

Biological Activities of Triterpenoids and Phenolic Compounds from Myrica cerifera Bark

Seven triterpenoids, 1 - 7, two diarylheptanoids, 8 and 9, four phenolic compounds, 10 - 13, and three other compounds, 14 - 16, were isolated from the hexane and MeOH extracts of the bark of Myrica cerifera L. (Myricaceae). Among these compounds, betulin (1), ursolic acid (3), and myricanol (8) exhibited cytotoxic activities against HL60 (leukemia), A549 (lung), and SK-BR-3 (breast) human cancer cell lines (IC₅₀ 3.1 - 24.2 μm). Compound 8 induced apoptotic cell death in HL60 cells (IC₅₀ 5.3 μm) upon evaluation of the apoptosis-inducing activity by flow cytometric analysis and by Hoechst 33342 staining method. Western blot analysis on HL60 cells revealed that 8 activated caspases-3, -8, and -9 suggesting that 8 induced apoptosis via both mitochondrial and death receptor pathways in HL60. Upon evaluation of the melanogenesis-inhibitory activity in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), erythrodiol (7), 4-hydroxy-2-methoxyphenyl β-d-glucopyranoside (13), and butyl quinate (15) exhibited inhibitory effects (65.4 - 86.0% melanin content) with no, or almost no, toxicity to the cells (85.9 - 107.4% cell viability) at 100 μm concentration. In addition, 8, myricanone (9), myricitrin (10), protocatechuic acid (11), and gallic acid (12) revealed potent DPPH radical-scavenging activities (IC₅₀ 6.9 - 20.5 μm).

In vivo Toxicity Studies on Gall Extracts of Terminalia chebula (Gaertn.) Retz. (Combretaceae)

The galls of Terminala chebula (Gaertn.) Retz. (Combretaceae) are used for the treatment of various diseases in folk medicine and has been found to posses anti-inflammatory, anti-bacterial, anti-helmintic, anti-tyrosinase, and anti-aging activities. Considering the ethano-botanical and diverse pharmacological applications of galls of T. chebula, in this study, we investigate the possible toxic effects of different gall extracts of T. chebula by Brine shrimp (Artemia salina) toxicity assay. The cytotoxicity test of leaf gall extracts (petroleum ether, chloroform, ethanol, and aqueous) of T. chebula was evaluated by Brine shrimp (A. salina) toxicity assay, which is based on the ability to kill laboratory cultured Artemia nauplii (animals eggs) and also total content of polyphenols, flavonoids with other qualitative phytochemical analysis of the extract were determined. It was observed that the petroleum ether extract was virtually nontoxic on the shrimps, and exhibited very low toxicity with LC₅₀ value of 4356.76 μg/ml. Furthermore, the chloroform extract exhibited very low toxicity, giving LC₅₀ value of 1462.2 μg/ml. On the other hand, the ethanol extract was very toxic to brine shrimps with LC₅₀ value of 68.64 μg/ml. The ethanol extract had the highest total phenolic and flavonoid content of 136 ± 1.5 mg of gallic acid equivalent/g d.w and 113 ± 1.6 mg of quercetin equivalent/g d.w, respectively. The higher toxicity effect was positively correlated to the high content of total polyphenols/flavonoids in the extract. This significant lethality of different extracts to brine shrimp is an indicative of the presence of potent cytotoxic components which warrants further investigation.

Evaluating the Anticancer Potential of Ethanolic Gall Extract of Terminalia chebula (Gaertn.) Retz. (Combretaceae)

Plants have been an important source for discovery of anticancer compounds. With the current decline in the number of new molecular entities from the pharmaceutical industry, novel anticancer agents are being sought from traditional medicines; therefore the anticancer efficacy of many plants that are used in traditional medicine is yet to be verified. The objective of the study was to evaluate the cytotoxic potential of ethanolic leaf gall extract of Terminalia chebula are evaluated against buffalo rat liver 3A, MCF-7 (Human mammary gland adenocarcinoma) and A-549 (Human lung cancer) cell lines. The cytotoxic effect of the ethanolic extract was evaluated by MTT assay. The extract was potent and effective in inducing cytotoxic effects in all the cell lines with an IC₅₀ value of 305.18 ± 1.7 μg/mL, 643.13 ± 4.2 μg/mL, and 208.16 ± 3.7 μ/mL, respectively. The extract was more effective against A549 cell lines when compared to others. The presences of phenolics, triterpenoids, and flavonoids were identified in the extract. The extract showed total phenolic and flavonoid content of 478 ± 2.2 mg of gallic acid equivalent/g d.w and 538 ± 1.4 mg of quercetinequivalent/g d.w, respectively. This higher content of total phenolics and flavonoids found in the ethanolic extract was directly associated to higher cytotoxicity activity.

Comparison of pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of the fruit of Terminalia chebula and a Mongolian compound medicine-Gurigumu-7

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Terminalia chebula (fructus chebulae) is an important Traditional Medicine used for intestinal and hepatic detoxification. Gurigumu-7 which is made of fructus chebulae and 6 other traditional medicines is one of the most frequently used compound Mongolian and Tibet medicines for liver diseases. Terminalia phenolics are considered as the bioactive constituents of fructus chebulae and consequently of Gurigumu-7.

AIM OF THE STUDY

To compare the pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7 and to evaluate the possible influence of intestinal bacterial metabolism on these pharmacokinetic profiles.

MATERIALS AND METHODS

An ultra performance liquid chromatography with triple quadrupole mass spectrometry method was established and validated for simultaneously determining the pharmacokinetic profiles of seven Terminalia phenolics after intragastric administration of pure compounds, fructus chebulae extract, and Gurigumu-7 extract. In vitro rat fecal lysates experiments were carried out to explore the metabolic discrepancy between fructus chebulae and Gurigumu-7.

RESULTS

Seven Terminalia phenolics were detected in rat plasma after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7. Administration of Gurigumu-7 could promote the absorption and increase the Cmax and AUC values of these phenolic constituents compared to fructus chebulae administration. The fecal lysates studies showed that the Terminalia phenolics in Gurigumu-7 were less rapidly bio-transformed than those in fructus chebulae. This may be a contributing factor to the pharmacokinetic discrepancy between the phenolics in fructus chebulae and Gurigumu-7.

CONCLUSION

Administration of Gurigumu-7 could increase the absorption of Terminalia phenolics through slowing down the intestinal bacteria metabolism. These results provide, in part, an in vivo rationale for the formulation of the traditional Mongolia / Tibet medicine, Gurigumu-7.

Anti-Lipoxygenase Activity of Leaf Gall Extracts of Terminalia chebula (Gaertn.) Retz. (Combretaceae)

Lipoxygenase (LOX) inhibitors are the promising therapeutic target for treating a wide spectrum of inflammatory-related diseases such as cancer, asthma, lymphoma, leukemia, and autoimmune disorders. In the present study, the photochemical constituents and the anti-LOX potential of leaf galls of Terminalia chebula are evaluated to exemplify its further potential development as medicine. Extracts of T. chebula galls were tested for anti-LOX activity using linoleic acid as substrate and lipoxidase as an enzyme and also the total content of polyphenols with phytochemical analysis of the extract were determined. The presence of highest total phenolic and flavonoid content of 141 ± 2.2 mg of gallic acid equivalent/g d.w and 125 ± 1.4 mg of quercetin equivalent/g d.w and maximal LOX inhibitory activity (52.67%) at 800 μg/mL concentrations were identified in the ethanolic extracts of leaf galls of T.chebula. The higher LOX inhibitory activity was positively correlated to the high content of total polyphenols/flavonoids. The results of this study confirm the folklore use of T. chebula leaves gall extracts as a natural anti-inflammatory agent and justify its ethnobotanical use. Therefore, the results encourage the use of T. chebula leave gall extracts for medicinal health, functional food, and nutraceuticals applications.

A Review on Potential Mechanisms of Terminalia chebula in Alzheimer's Disease

The current management of Alzheimer's disease (AD) focuses on acetylcholinesterase inhibitors (AChEIs) and NMDA receptor antagonists, although outcomes are not completely favorable. Hence, novel agents found in herbal plants are gaining attention as possible therapeutic alternatives. The Terminalia chebula (Family: Combretaceae) is a medicinal plant with a wide spectrum of medicinal properties and is reported to contain various biochemicals such as hydrolysable tannins, phenolic compounds, and flavonoids, so it may prove to be a good therapeutic alternative. In this research, we reviewed published scientific literature found in various databases: PubMed, Science Direct, Scopus, Web of Science, Scirus, and Google Scholar, with the keywords: T. chebula, AD, neuroprotection, medicinal plant, antioxidant, ellagitannin, gallotannin, gallic acid, chebulagic acid, and chebulinic acid. This review shows that T. chebula extracts and its constituents have AChEI and antioxidant and anti-inflammatory effects, all of which are currently relevant to the treatment of Alzheimer's disease.

Gastroprotective activity of chloroform extract of Muntingia calabura and Melastoma malabathricum leaves

CONTEXT

Muntingia calabura L. (family Muntingiaceae) and Melastoma malabathricum L. (family Melastomaceae) are traditionally used to treat gastric ulcer.

OBJECTIVE

The present study determines the mechanisms of gastroprotective activity of the chloroform extract of leaves obtained from both the plants using several in vitro and in vivo assays.

MATERIALS AND METHODS

Phytochemical screening, HPLC analysis, and antioxidant activity of the respective extract were carried out. Gastroprotective activity was determined using ethanol-induced gastric ulcer assay while the mechanisms of gastroprotection were determined using the pyloric ligation assay. The test solutions [8% Tween-80 (vehicle), 20 mg/kg omeprazole, and different doses of extracts (50, 250, or 500 mg/kg] were administered orally once daily for 7 consecutive days before the animals were subjected to ethanol induced gastric ulcers.

RESULTS

The chloroform-extracted M. calabura (CEMC) contains tannins, polyphenolics, triterpenes, and steroids while the chloroform-extracted M. malabathricum (CEMM) contains only triterpenes and steroids. CEMC, but not CEMM, exerted remarkably strong antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH)- (86% versus 16%) and superoxide- (73% versus 36%) radical scavenging assays. Both extracts demonstrated significant (p < 0.05) gastroprotection with the EC50 value recorded at 192.3 or 297.7 mg/kg, respectively. In the pylorus ligation assay, CEMC and CEMM significantly (p < 0.05) reduced the total and free acidity and volume; while increased the pH of gastric juice as well as the gastric wall mucus content in comparison with the vehicle-treated group.

DISCUSSION AND CONCLUSION

CEMC and CEMM exert gastroprotective effects in animals with ethanol-induced gastric ulcers via antioxidant and anti-secretory effects.

Critical review of Ayurvedic Varṇya herbs and their tyrosinase inhibition effect

INTRODUCTION

The aspiration for light skin (fair complexion) is becoming pronounced in a greater number of people in the present times with natural products being more in demand than their synthetic counterparts. Research in the area of skin-lightening agents is an expanding field with the knowledge being updated regularly. In Ayurveda, varṇya, raktaprasādana, tvacya are few terms specifying skin lightening with respect to its modern counterpart i.e., Tyrosinase inhibition, the most commonly reported method of skin lightening.

AIM

The present review is undertaken for screening twenty herbs from Varṇya Mahākaṣāya, Lodhrādi varṇya gaṇa, Elādi varṇa prasādana gaṇa and few varṇya formulations to evaluate their probable modes of action through which the skin lightening is effected as per both Ayurveda and biomedical concepts.

MATERIALS AND METHODS

Critical review of herbs to show varṇya property is compiled from various Ayurvedic texts as well as from multiple articles on the internet to justify their skin lightening property on the basis of data collected.

RESULT AND CONCLUSION

All the twenty herbs reviewed are found to act as varṇya directly (citation as varṇya) or indirectly (alleviation of pitta and rakta) as per Ayurveda and to interfere in melanogenesis pathway through tyrosinase inhibition as per biomedicine. This shows their potential to act as good skin whitening agents. Śuṇṭhi being a part of many varṇya formulations, is the only herb among all reviewed in the present study found to exhibit tyrosinase inhibition without any Ayurvedic citation of varṇya property.

A New Aromatic Compound from the Stem Bark of Terminalia catappa

A new aromatic compound 3,4,5-trimethoxyphenyl-1- O-(4-sulfo)-β-D-glucopyranoside (1), in addition to two triterpenoid saponins (chebuloside II, arjunoglucoside II), two triterpenes (arjunolic acid and 3-betulinic acid) and sitosterol-3- O-β-D-glucopyranoside have been isolated from the barks of Terminalia catappa. Their structures have been established on the basis of spectroscopic techniques (1D/2D NMR) and MS. Their cytotoxicity and anti-inflammatory activity, together with the antioxidant capacity of compound 1 were also evaluated.

Triterpene glycosides and other polar constituents of shea (Vitellaria paradoxa) kernels and their bioactivities

The MeOH extract of defatted shea (Vitellaria paradoxa; Sapotaceae) kernels was investigated for its constituents, and fifteen oleanane-type triterpene acids and glycosides, two steroid glucosides, two pentane-2,4-diol glucosides, seven phenolic compounds, and three sugars, were isolated. The structures of five triterpene glycosides were elucidated on the basis of spectroscopic and chemical methods. Upon evaluation of the bioactivity of the isolated compounds, it was found that some or most of the compounds have potent or moderate inhibitory activities against the following: melanogenesis in B16 melanoma cells induced by α-melanocyte-stimulating hormone (α-MSH); generation of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, against Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-teradecanoylphorbol 13-acetate (TPA) in Raji cells; t TPA-induced inflammation in mice, and proliferation of one or more of HL-60, A549, AZ521, and SK-BR-3 human cancer cell lines, respectively. Western blot analysis established that paradoxoside E inhibits melanogenesis by regulation of expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-1 (TRP-1) and TRP-2. In addition, tieghemelin A was demonstrated to exhibit cytotoxic activity against A549 cells (IC50 13.5 μM) mainly due to induction of apoptosis by flow cytometry. The extract of defatted shea kernels and its constituents may be, therefore, valuable as potential antioxidant, anti-inflammatory, skin-whitening, chemopreventive, and anticancer agents.

Antidiabetic potential of some less commonly used plants in traditional medicinal systems of India and Nigeria

The incidence of diabetes mellitus continue to rise annually all over the world with India and Nigeria having recorded cases of 65.1 and 3.9 million respectively in 2013 and expected to increase by a large amount in 2035. Hyperglycemia is a pre-condition for the development of diabetic complications and is accompanied by an increase in the production of free radicals. The present available treatment option for diabetes like sulfonylurea, metformin and alpha-glucosidase are restricted by their limited actions, secondary failure rates, and side-effects; and unaffordable to the majority of the population. Hence, the need to screen for more medicinal plants with antidiabetic ability due to the fact that plants are; biodegradable, safe and cheap with fewer side-effects. In this review article, we have presented the current status of diabetes in India and Nigeria and the role of some less commonly used medicinal plants from both countries that have antidiabetic potential.

Chemical constituents from Melastoma dodecandrum and their inhibitory activity on interleukin-8 production in HT-29 cells

In search of anti-inflammatory lead compounds from traditional Chinese medicines, a bioassay-guided phytochemical study on Melastoma dodecandrum was carried out. As a result, 18 compounds have been isolated. Their chemical structures were determined on the basis of their physicochemical properties and spectral data. Among the isolates, three pentacyclic triterpenoids, ursolic acid (1), asiatic acid (3) and terminolic acid (6), together with one tannin casuarinin (17), were found to significantly decrease interleukin-8 (IL-8) production in human colon cancer cells. The results imply, at least in part, that the anti-inflammatory effect of M. dodecandrum could be due to inhibition of IL-8 production, demonstrated by these naturally occurring compounds described above.

Multifunctional pentacyclic triterpenoids as adjuvants in cancer chemotherapy: a review

The protective adjuvants in chemotherapy.