Exploring the endogenous potential of Hemidesmus indicus against breast cancer using in silico studies and quantification of 2-hydroxy-4-methoxy benzaldehyde through RP-HPLC

Being a woman and getting older are the main risk factors for breast cancer. While admitting the increasing prevalence of breast cancer among females globally, there is an increasing urge for widening the range of chemical compounds that can act as potential inhibitors for certain cancer target receptors. Current investigation involves virtually screening of 19 protein receptors having major role in signal transduction pathway of breast cancer development against 47 compounds present in Hemidesmus indicus. Virtual screening and supplementary analysis were performed using freely available softwares, tools and online servers. To obtain meaningful results, a comparative scenario was created by screening FDA-approved drugs/drug analogues against the same 19 receptors by keeping all the parameters same as to that of ligands. Two ligands namely Taraxasteryl acetate and Rutin were found to be the best ligands with high binding affinity towards six protein receptors establishing strong receptor ligand interactions. Furthermore, the major volatile compound, a high demand flavouring agent and an isomer of vanillin, namely 2-hydroxy-4-methoxy benzaldehyde (MBALD) specifically found in the roots of Hemidesmus, was quantified by RP-HPLC using a reverse phase C-18 column. The methanolic extract of fresh roots was found to contain 0.221 mg of MBALD/gram of tissue. From the current investigation, it could be surmised that Hemidesmus indicus had demonstrated its potential in both pharmaceuticals and the food industry.

Indian Sarsaparilla (Hemidesmus indicus): Recent progress in research on ethnobotany, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Hemidesmus indicus (L.) R. Br. ex Schult. (Apocynaceae) is widely used in traditional medicine in the different parts of the Indian subcontinent due to the various biological activities attributed to its different parts, especially the roots. It has traditionally been used for treating snakebites, scorpion stings, diabetes, urinary diseases, dyspnea, menorrhagia, oligospermia, anorexia, fever, abdominal colic and pain, dysentery, diarrhea, cough, rheumatism, headache, inflammation, pyrosis, skin diseases, leprosy, sexually transmitted diseases and cancer. In Ayurveda, the plant is used in the treatment of bone-loss, low body weight, fever, stress, topical wound and psoriasis. Besides, Ayurvedic literature also depicts its use as anti-atherogenic, anti-spasmodic, memory enhancing, immunopotentiating and anti-inflammatory agents.

AIM OF THE STUDY

In this review, we aim to present a comprehensive update on the ethnopharmacology, phytochemistry, specific pharmacology, and toxicology of H. indicus and its bioactive metabolites. Possible directions for future research are also outlined in brief.

MATERIALS AND METHODS

Popular and widely used international databases such as PubMed, Scopus, Science Direct, Google Scholar and JSTOR were searched and traditional literature were consulted using the various search strings to retrieve a number of citations related to the ethnopharmacology, biological activity, toxicology, quality control and phytochemistry of H. indicus. All studies on the ethnobotany, phtochemistry, pharmacology, and toxicology of the plant up to 2019 were included in this review.

RESULTS

H. indicus has played an important role in traditional Indian medicine (including Ayurveda) and also in European medicine. The main pharmacological properties of H. indicus include hepatoprotective, anti-cancer, anti-diabetic, antioxidant, neuroprotective, anti-ophidian, cardioprotective, nephroprotective, anti-ulcerogenic, anti-inflammatory, and antimicrobial properties. Phytochemical evaluations of the root have revealed the presence of aromatic aldehydes and their derivatives, phenolics, triterpenoids and many other compounds, some of which were attributed to its bioactivity. This review also compiles a list of Ayurvedic formulations and commercial preparations where H. indicus has been used as an active ingredient. We have included the critical assessment of all the papers cited in this manuscript based on experimental observation and other important points which reflect the loop-holes of research strategy and ambiguity in the papers reviewed in this manuscript.

CONCLUSIONS

The study presents an exhaustive and updated review on the traditional, pharmacological and phytochemical aspects of H. indicus with notes on its quality control and toxicological information. Although the crude extracts of H. indicus exhibit an array of pharmacological activities, it is high time to identify more active phyto-constituents by bioactivity-guided isolation besides elucidating their structure-activity relationship. More designed investigations are needed to comprehend the multi-target network pharmacology, to clarify the molecular mode of action and to ascertain the efficacious doses of H. indicus. Moreover, H. indicus is not fully assessed on the basis of its safety and efficacy on human. We hope this review will compile and improve the existing knowledge on the potential utilization of H. indicus in complementary and alternative medicine.

The Mechanism of Ca(2+) Movement in the Involvement of Baicalein-Induced Cytotoxicity in ZR-75-1 Human Breast Cancer Cells

Baicalein (5,6,7-trihydroxyflavone) (1) has been found to be active against a wide variety of cancer cells. However, the molecular mechanism underlying the effects of 1 on the induction of Ca(2+) movement and cytotoxicity in human breast cancer cells is unknown. This study examined the relationship between 1-induced Ca(2+) signaling and cytotoxicity in ZR-75-1 human breast cancer cells. The in vitro investigations reported herein produced the following results: (i) Compound 1 increased intracellular Ca(2+) concentration ([Ca(2+)]i) in a concentration-dependent manner. The signal was decreased by approximately 50% by removal of extracellular Ca(2+). (ii) Compound 1-triggered [Ca(2+)]i increases were significantly suppressed by store-operated Ca(2+) channel blockers 2-aminoethoxydiphenyl borate (2-APB) and the PKC inhibitor GF109203X. (iii) In Ca(2+)-free medium, compound 1-induced [Ca(2+)]i increases were also inhibited by GF109203X. Furthermore, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-ditert-butylhydroquinone (BHQ) abolished 1-induced [Ca(2+)]i increases. Inhibition of phospholipase C (PLC) with U73122 abolished 1-induced [Ca(2+)]i increases. (iv) Compound 1 (20-40 μM) caused cytotoxicity, increased reactive oxygen species (ROS) production, and activated caspase-9/caspase-3. Furthermore, compound 1-induced apoptosis was significantly inhibited by prechelating cytosolic Ca(2+) with BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester) or by decreasing ROS with the antioxidant NAC (N-acetylcysteine). Together, baicalein (1) induced a [Ca(2+)]i increase by inducing PLC-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via PKC-dependent, 2-APB-sensitive store-operated Ca(2+) channels. Moreover, baicalein (1) induced Ca(2+)-associated apoptosis involved ROS production in ZR-75-1 cells.

Voacamine modulates the sensitivity to doxorubicin of resistant osteosarcoma and melanoma cells and does not induce toxicity in normal fibroblasts

In previous studies it has been demonstrated that the plant alkaloid voacamine (1), used at noncytotoxic concentrations, enhanced the cytotoxicity of doxorubicin and exerted a chemosensitizing effect on cultured multidrug-resistant (MDR) U-2 OS-DX osteosarcoma cells. The in vitro investigations reported herein gave the following results: (i) the chemosensitizing effect of 1, in terms of drug accumulation and cell survival, was confirmed using SAOS-2-DX cells, another MDR osteosarcoma cell line; (ii) compound 1 enhanced the cytotoxic effect of doxorubicin also on the melanoma cell line Me30966, intrinsically drug resistant and P-glycoprotein-negative; (iii) at the concentrations used to sensitize tumor cells, 1 was not cytotoxic to normal cells (human fibroblasts). These findings suggest possible applications of voacamine (1) in integrative oncologic therapies against resistant tumors.