Anticancer and antiviral activities in indian medicinal plants: A review

Modulation of atrazine-induced chromosomal aberrations and cyclin-dependent kinases by aqueous extract of Roylea cinerea (D.Don) Baillon leaves in Allium cepa

Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol^®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.

Wikstroemiaganpi Extract Improved Atopic Dermatitis-Like Skin Lesions via Suppression of Interleukin-4 in 2,4-Dinitrochlorobenzene-Induced SKH-1 Hairless Mice

Plants of the genus Wikstroemia are used in Chinese traditional medicine to treat inflammatory diseases, such as arthritis, bronchitis, and pneumonia. The present study was designed to determine whether Wikstroemia ganpi (Siebold and Zucc.) Maxim. offers a potential means of treating 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Symptoms such as redness, edema, and keratinization in AD mice induced by DNCB were alleviated by the co-application of an ethanolic extract of W. ganpi for 2 weeks. The severity of skin barrier function damage was evaluated by measuring TEWL (transepidermal water loss). TEWLs of DNCB sensitized mouse dorsal skin were reduced by the application of a W. ganpi ethanolic extract, and skin hydration was increased. In addition, the infiltration of inflammatory cells into the dermis was significantly reduced, as were blood levels of IgE and IL-4, which play an important role in the expression of AD. The results of this experiment suggest that W. ganpi is a potential therapeutic agent for AD.

Repurposing drugs against the main protease of SARS-CoV-2: mechanism-based insights supported by available laboratory and clinical data

The ongoing global pandemic of COVID-19 has brought life to almost a standstill with the implementation of lockdowns and social distancing as some of the preventive measures in the absence of any approved specific therapeutic interventions. To combat this crisis, research communities worldwide are falling back on the existing repertoire of approved/investigational drugs to probe into their anti-coronavirus properties. In this report, we describe our unique efforts in identifying potential drugs that could be repurposed against the main protease of SARS-CoV-2 (SARS-CoV-2 M^pro). To achieve this goal, we have primarily exploited the principles of 'neighbourhood behaviour' in the protein 3D (workflow-I) and chemical 2D structural space (workflow-II) coupled with docking simulations and insights into the possible modes of action of the selected candidates from the available literature. This integrative approach culminated in prioritizing 29 potential repurpose-able agents (20 approved drugs and 9 investigational molecules) against SARS-CoV-2 M^pro. Apart from the approved/investigational anti-viral drugs, other notable hits include anti-bacterial, anti-inflammatory, anti-cancer and anti-coagulant drugs. Our analysis suggests that some of these drugs have the potential to simultaneously modulate the functions of viral proteins and the host response system. Interestingly, many of these identified candidates (12 molecules from workflow-I and several molecules, belonging to the chemical classes of alkaloids, tetracyclines, peptidomimetics, from workflow-II) are suggested to possess anti-viral properties, which is supported by laboratory and clinical data. Furthermore, this work opens a new avenue of research to probe into the molecular mechanism of action of many drugs, which are known to demonstrate anti-viral activity but are so far not known to target viral proteases.

Antiproliferative Effects of Roylea cinerea (D. Don) Baillon Leaves in Immortalized L6 Rat Skeletal Muscle Cell Line: Role of Reactive Oxygen Species Mediated Pathway

Roylea cinerea (D. Don) Baill. (Lamiaceae) is an indigenous plant of Western Himalayas, and has been used by the native population for the treatment of various diseases such as fever, malaria, diabetes, jaundice, and skin ailments. However, limited proportion of pharmacological and toxicological information is available on the bioactive properties of this plant. Therefore, the present study was designed to explore the anti-oxidant and anti-proliferative activities of Roylea cinerea. Methanolic extracts of leaves and stem of Roylea cinerea were prepared through maceration procedure and evaluated for the antioxidant activity using hydrogen/electron donating and hydroxyl radical scavenging assay. Significant antioxidant activity was observed for the methanolic extract of leaves in DPPH (EC₅₀ 239 µg/ml), molybdate ion reduction assay (29.73 µg ascorbic acid equivalent/mg dry weight of extract) as well as in plasmid nicking assay. Anti-proliferative and apoptotic activity in L6 rat skeletal muscle cell line was done using in vitro assays, i.e., MTT, Lactate dehydrogenase, mitochondrial membrane potential assay along with phase contrast, confocal, and scanning electron microscopy. The methanol extract of leaves and stem inhibited the growth of L6 cells with IC₅₀ value of 69.41µg/ml and 124.93 µg/ml, respectively, and the lactate dehydrogenase activity was 20.29% and 0.3%, respectively. Cell cycle analysis by flow cytometry exhibited the arrest of cells in G1 and sub-G1 phase by methanolic leaves extract. Furthermore, the results of microscopic and docking analysis strengthened the observation made in the present study regarding the apoptotic mode of cell death in the L6 cell line. The in vitro findings of our studies revealed that the bioactive ingredients present in the methanolic extract of leaves and stem of Roylea cinerea have the anticancer potential. Further in vivo studies are needed to verify the in vitro results.

Suppression of DNCB-Induced Atopic Skin Lesions in Mice by Wikstroemia indica Extract

Wikstroemia indica (L.) C.A. Mey. is used in traditional Chinese medicine to treat inflammatory diseases such as arthritis and bronchitis. In this study, we aimed to investigate the effects of an ethanolic extract of W. indica on cutaneous inflammation in mice with 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD). Dermal administration of W. indica ethanolic extract to DNCB-sensitized hairless mice with dermatitis, for two weeks, reduced erythema, scaling, and edema. Skin hydration was improved and transepidermal water loss was reduced at a W. indica concentration of 1%. Furthermore, W. indica also significantly reduced serum IgE and IL-4 concentrations in our mouse model. These results suggest that W. indica has potential as a topical treatment for AD and as an adjunctive agent to control AD.

Roylea cinerea (D.Don) Baillon: Ethnomedicinal uses, phytochemistry and pharmacology: A review

ROYLEA CINEREA (D.DON) BAILLON: Roylea cinerea (D.Don) Baillon family Lamiaceae is a shrub of the monotypic genus. Aerial parts of the plant are used traditionally in Indian sub-Himalayas and Nepal for the treatment of jaundice, skin diseases, malaria, diabetes, febrifuge and contusions.

METHOD

This article reviews botanical description, phytochemistry, ethnomedicinal uses and pharmacological activities of R. cinerea to evaluate if the scientifically evaluated pharmacological profile of the plant can corroborate ethnomedicinal uses. A survey was conducted to document ethnomedicinal and folklore uses of the plant in five districts of Himachal Pradesh, India.

RESULTS

Phytochemical studies of R. cinerea reveal the presence of glycosides, diterpenes, flavonoids, tannins, steroids, saponins and phenols. R. cinerea extracts. The compounds showed anticancer, antifungal, hepatoprotective, antiperiodic, antiprotozoal, antidiabetic and antioxidant activities on scientific evaluation. A diterpenoid from the plant, precalyone, exhibited antiproliferative activity against P-388 lymphocytic leukemia cell line. Cinereanoid D, a labdane diterpenoid that inhibits ATP binding of heat shock protein Hsp90, is a potential anticancer lead. Two compounds from aerial parts of the plant, 4-methoxybenzo[b]azet-2(1H)-one and 3β-hydroxy-35-(cyclohexyl-5'-propan-7'-one)-33-ethyl-34-methylbacteriohop-16-ene, showed antidiabetic activity. Thus, the scientific reports confirm the ethnomedicinal use of this plant in diabetes, malaria and liver diseases.

CONCLUSION

Roylea cinerea is a traditionally used medicinal plant from Western Himalayas. The pharmacological evaluation confirmed the ethnomedically claimed antidiabetic activity using scientifically accepted protocols and controls, although some of the studies require reconfirmation. The bioactivity-guided fractionation attributes the activity to 4-methoxybenzo[b]azet-2(1H)-one and 3β-hydroxy-35-(cyclohexyl-5'-propan-7'-one)-33-ethyl-34-methylbacteriohop-16-ene. Further, cinereanoid D is a potential lead for targeting Hsp90 and its medicinal chemistry studies can lead to a potent anticancer compound. The plant extract also showed antimalarial and hepatoprotective activities. Some of the studies discussed in this review require reconfirmation, as the protocols lacked proper positive and negative controls. Thus, the review of the scientific reports on Roylea cinerea supports ethnomedicinal use as antidiabetic, antimalarial and hepatoprotective. Further studies to prove scientific basis for use in leucorrhea, skin diseases, inflammation and strengthening of claims for liver tonic are required.

Cryopreservation of Orchids - A Review

BACKGROUND

The orchids are one of the beautiful creations of nature which stand apart from any other assemblage of flowering plants. They are highly evolutionary and ecologically significant group of plants that have effectively occupied almost every habitat on the earth. Indiscriminate collections and extermination of their natural habitats have threatened many species of orchids with extinction, resulting in a severe reduction of their genetic resources in nature according to recent patents. It is necessary to adopt sound scientific protocols for the preservation of orchid species.

METHOD

This cost-effective technique provides large storage time for the conservation of germplasm. Presently, efforts have been made to explore various cryopreservation techniques utilized so far and factors affecting the longevity of the propagules (in vivo and in vitro) while cryopreserving them. The sample to be cryopreserved is freeze-preserved in two ways, a) stepwise at two different subzero temperatures and b) in the rapid method, the samples are placed directly in the liquid nitrogen.

RESULTS

The orchid seeds and pollen are the most suitable propagules for cryopreservation of orchids due to their minute size and less space requirement.

CONCLUSION

Among the tissues (such as seeds, pollen, protocorms etc.) seeds are the most reliable. The present article reviews the cryopreservation techniques and factors effecting the cryopreservation, for in vitro conservation of orchid gene pool.

The medicinal plants of Myanmar

A comprehensive compilation is provided of the medicinal plants of the Southeast Asian country of Myanmar (formerly Burma). This contribution, containing 123 families, 367 genera, and 472 species, was compiled from earlier treatments, monographs, books, and pamphlets, with some medicinal uses and preparations translated from Burmese to English. The entry for each species includes the Latin binomial, author(s), common Myanmar and English names, range, medicinal uses and preparations, and additional notes. Of the 472 species, 63 or 13% of them have been assessed for conservation status and are listed in the IUCN Red List of Threatened Species (IUCN 2017). Two species are listed as Extinct in the Wild, four as Threatened (two Endangered, two Vulnerable), two as Near Threatened, 48 Least Concerned, and seven Data Deficient. Botanic gardens worldwide hold 444 species (94%) within their living collections, while 28 species (6%) are not found any botanic garden. Preserving the traditional knowledge of Myanmar healers contributes to Target 13 of the Global Strategy for Plant Conservation.

Antidiabetic effect of Streblus asper in streptozotocin-induced diabetic rats

CONTEXT

In the Indian traditional system of medicine, Streblus asper Lour (Moraceae) is prescribed for the treatment of diabetes mellitus.

OBJECTIVE

In the present study, α-amyrin acetate isolated from S. asper, and the petroleum ether extract of S. asper stem bark (PESA) was screened for their antidiabetic properties in streptozotocin (STZ)-induced diabetic rats.

MATERIALS AND METHODS

Successive Soxhlet extraction of the dried stem bark with petroleum ether and then with ethanol (95%) yielded petroleum ether and ethanol extracts, respectively, which were concentrated under reduced pressure. Hyperglycemia was induced in rats by STZ (50 mg/kg, b.w.). Twenty-four hours after STZ induction, respective groups of diabetic rats received PESA (100, 250 and 500 mg/kg, b.w.) and α-amyrin acetate (25, 50 and 75 mg/kg, b.w.) respectively, orally daily for 15 days. Glibenclamide (0.5 mg/kg, orally) served as a reference. Blood glucose levels were measured on every 5th day during the 15 days of treatment. The serum lipid profiles and biochemical parameters, viz., serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP), insulin and glycosylated hemoglobin level, were measured.

RESULTS

PESA significantly (p < 0.01) normalized blood-glucose levels and serum biochemical parameters as compared with those of STZ controls. α-Amyrin acetate (75 mg/kg, b.w.) exhibited maximum glucose lowering effect (71.10%) in diabetic rats compared to the other dose (25, 50 mg/kg) at the end of the study. The protective effect was further confirmed by histopathological examination of the liver.

CONCLUSION

PESA and α-amyrin acetate demonstrated remarkable antidiabetic activity in STZ-induced diabetic rats.

In vitro anti-breast cancer activity of ethanolic extract of Wrightia tomentosa: role of pro-apoptotic effects of oleanolic acid and urosolic acid

ETHNOPHARMACOLOGICAL RELEVANCE

Wrightia tomentosa Roem. & Schult. (Apocynaceae) is known in the traditional medicine for anti-cancer activity along with other broad indications like snake and scorpion bites, renal complications, menstrual disorders etc. However, the anti-cancer activity of this plant or its constituents has never been studied systematically in any cancer types so far.

AIM OF THE STUDY

To evaluate the anti-cancer activities of the ethanolic extract of W. tomentosa and identified constituent active molecule(s) against breast cancer.

MATERIAL AND METHODS

Powdered leaves of W. tomentosa were extracted with ethanol. The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa were tested for its anti-proliferative and pro-apoptotic effects in breast cancer cells MCF-7 and MDA-MB-231.

RESULTS

The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa inhibited the proliferation of human breast cancer cell lines, MCF-7 and MDA-MB-231. The fraction F-4 obtained from hexane fraction inhibited proliferation of MCF-7 and MDA-MB-231 cells in concentration and time dependent manner with IC₅₀ of 50 μg/ml and 30 μg/ml for 24 h, 28 μg/ml and 22 μg/ml for 48 h and 25 μg/ml and 20 μg/ml for 72 h respectively. The fraction F-4 induced G1 cell cycle arrest, reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential and subsequent apoptosis. Apoptosis is indicated in terms of increased Bax/Bcl-2 ratio, enhanced Annexin-V positivity, caspase 8 activation and DNA fragmentation. The active molecule isolated from fraction F-4, oleanolic acid and urosolic acid inhibited cell proliferation of MCF-7 and MDA-MB-231 cells at IC₅₀ value of 7.5 μM and 7.0 μM respectively, whereas there is devoid of significant cell inhibiting activity in non-cancer originated cells, HEK-293. In both MCF-7 and MDA-MB-231, oleanolic acid and urosolic acid induced cell cycle arrest and apoptosis as indicated by significant increase in Annexin-V positive apoptotic cell counts.

CONCLUSION

Our results suggest that W. tomentosa extracts has significant anti-cancer activity against breast cancer cells due to induction of apoptosis pathway. Olenolic and urosolic acid are important constituent molecules in the extract responsible for anti-cancer activity of W. tomentosa.

Anti-Viral Activity of Indian Plants

Plants continue to be a major source for new chemical entities to develop novel therapeutic agents. Large number of plants has been shown to be active in vitro against a variety of human pathogenic viruses or their near congeners. In several cases the active compounds have been isolated and characterized. Very few of them, however, have been investigated in detail in vivo or taken to the clinic. Pure compounds like andrographolide, curcumin and glycyrrhizic acid as well as extracts of Azadirachta indica have shown activity against several viruses and should be investigated further for their therapeutic potential. An analysis of available data from several hundred species indicates that antiviral activity is more likely to be found in plants belonging to certain families. It is necessary to screen more plants of these families which are available in India to obtain further leads.

Therapeutic orchids: traditional uses and recent advances--an overview

Orchids have been used as a source of medicine for millennia to treat different diseases and ailments including tuberculosis, paralysis, stomach disorders, chest pain, arthritis, syphilis, jaundice, cholera, acidity, eczema, tumour, piles, boils, inflammations, menstrual disorder, spermatorrhea, leucoderma, diahorrhea, muscular pain, blood dysentery, hepatitis, dyspepsia, bone fractures, rheumatism, asthma, malaria, earache, sexually transmitted diseases, wounds and sores. Besides, many orchidaceous preparations are used as emetic, purgative, aphrodisiac, vermifuge, bronchodilator, sex stimulator, contraceptive, cooling agent and remedies in scorpion sting and snake bite. Some of the preparations are supposed to have miraculous curative properties but rare scientific demonstration available which is a primary requirement for clinical implementations. Incredible diversity, high alkaloids and glycosides content, research on orchids is full of potential. Meanwhile, some novel compounds and drugs, both in phytochemical and pharmacological point of view have been reported from orchids. Linking of the indigenous knowledge to the modern research activities will help to discover new drugs much more effective than contemporary synthetic medicines. The present study reviews the traditional therapeutic uses of orchids with its recent advances in pharmacological investigations that would be a useful reference for plant drug researches, especially in orchids.

Anti-inflammatory effect of Streblus asper leaf extract in rats and its modulation on inflammation-associated genes expression in RAW 264.7 macrophage cells

AIM OF THIS STUDY

Streblus asper is a medicinal plant from Thailand used in folk medicine for the treatment of several inflammatory diseases. In this study, we investigated the anti-inflammatory effect of Streblus asper leaf ethanolic extract (SAE).

MATERIALS AND METHODS

The experimental carrageenan-induced paw edema in rats was performed in which the SAE at doses of 125, 250, 500 mg/kg body weight was intraperitoneally administered to the rats. Then, reverse transcriptive polymerase chain reaction (RT-PCR) technique was also performed to determine the effect of SAE on the expression of inflammation-associated genes in RAW 264.7 macrophage cells stimulated with lipopolysaccharide (LPS).

RESULTS

The SAE at all given doses caused a significant dose-dependent inhibition of edema (p<0.05). Moreover, the significant and dose-dependent LPS-induced cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) mRNA expressions were demonstrated in RAW 264.7 cells treated with SAE. The inhibition is selective, since COX-1 mRNA expression did not change in the presence of SAE.

CONCLUSION

The results of this study are the first scientific evidence on the molecular effects of Streblus asper as a potential anti-inflammatory agent, which supports the fact that the plant is employed in traditional remedies.

Pharmacology and chemotaxonomy of Diospyros

Diospyros is numerically and economically the most important genus of Ebenaceae. The medicinal uses and chemical constituents of various Diospyros species are now reviewed. About 300 organic chemicals have been isolated and identified. The uniqueness of the genus is the elaboration of a large number of pentacyclic triterpenes and juglone based 1,4-naphthoquinone metabolites. These metabolites can be used as chemical markers for taxonomic studies. A common biogenetic pathway for their co-occurrence is now proposed. Various compounds are tabulated according to their classes and their structures are given in the Appendix.