Chemical constituents of gentianaceae. IX. Natural occurrence of erythrocentaurin in Enicostemma hyssopifolium and Swertia lawii

Systems pharmacology and multi-scale mechanism of Enicostema axillare bioactives in treating Alzheimer disease

As a progressive neurological disease with increased morbidity and mortality, Alzheimer Disease (AD) is characterized by neuron damage that controls memory and mental functions. Enicostema axillare (EA), an herb with a history of combativeness and effectiveness in treating Rheumatoid Arthritis, Cancer, and Diabetes, is used in Indian folk medicine from a holistic point of view. Though the herb is used for many illnesses, the molecular mechanism of its bioactive on AD has not been deciphered by intricate research. A unique pharmacology approach based on ADME drug screening and targeting, pathway enrichment (GO and KEGG), and network pharmacology, was established to explore the molecular mechanisms of E. axillare (EA) bioactive compounds for the treatment of AD. In brief, we bring to light the three active compounds of EA and seven potential molecular targets of AD, which are mainly implicated in four signaling pathways, i.e., MAPK, Apoptosis, neurodegeneration, and the TNF pathway. Moreover, the network analysis of the active compounds, molecular targets, and their pathways reveals the pharmacological nature of the compounds. Further, molecular docking studies were carried out to explore the interactions between the EA bioactive compounds and the targets and examine the binding affinity. The outcome of the work reflects the potential therapeutic effects of the compounds for treating AD through the modulation of the key proteins, which further corroborates the reliability of our network pharmacology analysis. This study not only helps in understanding the molecular mechanism of the drugs but also helps in finding and sorting new drugs for the treatment of AD, and other complex diseases through modern medicine.

Feature-Based Molecular Networks Identification of Bioactive Metabolites from Three Plants of the Polynesian Cosmetopoeia Targeting the Dermal Papilla Cells of the Hair Cycle

The term cosmetopoeia refers to the use of plants in folks’ cosmetics. The aerial parts of Bidens pilosa L., the leaves of Calophyllum inophyllum L. and the fruits of Fagraea berteroana A.Gray ex Benth are traditionally used in French Polynesia for hair and skin care. During the hair cycle, dermal papilla cells and their interaction with epithelial cells are essential to promote hair follicle elongation. The aim of our investigations was the identification of metabolites from these three plants and chemical families responsible for their hair growth activity. A bioactivity-based molecular network was produced by mapping the correlation between features obtained from LC-MS/MS data and dermal papilla cell proliferation, using the Pearson correlation coefficient. The analyses pointed out glycosylated flavonols and phenolic acids from B. pilosa and C. inophyllum, along with C-flavonoids, iridoids and secoiridoids from F. berteroana, as potential bioactive molecules involved in the proliferation of hair follicle dermal papilla cells. Our results highlight the metabolites of the plant species potentially involved in the induction of hair follicle growth and support the traditional uses of these plants in hair care.

Investigation of phytoconstituents of Enicostemma littorale as potential glucokinase activators through molecular docking for the treatment of type 2 diabetes mellitus

Glucokinase (GK) is an enzyme involved in synthesising glucose into glucose-6 phosphate and serves a crucial function in glucose sensing. Therefore, agents that induce GK activation could be used to treat T2DM. The present work has been carried out to investigate the GK activation potential of phytoconstituents of Enicostemma littorale through molecular docking. All the phytoconstituents have been screened through the Lipinski rule of 5, Veber's rule, and ADMET properties. From these initial screening, only Apigenin, Ferulic acid, Genkwanin, p-coumaric acid, Protocatechuic acid, Syringic acid, and Vanillic acid have been selected to perform molecular docking studies. The binding free energy and binding mode of the native ligand in the allosteric site of the enzyme have been considered the reference for the other molecules' validation. The native ligand has exhibited - 7.2 kcal/mol binding free energy, whereas; it has formed four hydrogen bonds with THR-228, LYS-169, ASP-78, and GLY-81. Based on these findings, the interactions of phytoconstituents have been justified. Apigenin, genkwanin, and swertiamarin exhibited - 8.7, - 7.5, and - 8.3 kcal/mol binding free energy, respectively, which indicates better enzyme activation than the native ligand. Swertiamarin has formed 08 hydrogen bonds with allosteric amino acid residues, which confirms the excellent enzyme activation by these phytoconstituents. We concluded that if we can isolate and consume the exact active phytoconstituents (GK activators) from this plant, we can use them effectively to treat T2DM. More GK activators can be developed by considering them as a natural lead moiety.

Highly efficient in vitro regeneration, establishment of callus and cell suspension cultures and RAPD analysis of regenerants of Swertia lawii Burkill

Highly efficient in vitro regeneration system has been developed for Swertia lawii Burkill, an important herb used as substitute for Swertia chirayita. Shoot tips explants were cultured on MS medium with various phytohormones for multiple shoot production. The best shoot production frequency (100%) and maximum shoots (10.4 ± 0.8) were obtained on MS media containing TDZ (3.0 mg l-1) in combination with IBA (0.3 mg l-1). Maximum callus induction (95 ± 4.8%) and callus growth (1.7 ± 0.4 gm) was achieved on MS medium with 2, 4-D (3.0 mg l-1). Cell suspension cultures were established and studied for their growth kinetics. Shoots were rooted best (22.1 ± 2.5) in 1/2 MS medium with IAA (3.0 mg l-1). The genetic uniformity of the micropropagated clones was assessed using RAPD markers. Out of 405 bands, 400 (98.76%) were monomorphic and rest 5 (1.24%) were polymorphic. High multiplication frequency and low risk of genetic instability ensures the efficacy of this protocol.

Immunohistochemistry, histopathology, and biomarker studies of swertiamarin, a secoiridoid glycoside, prevents and protects streptozotocin-induced β-cell damage in Wistar rat pancreas

BACKGROUND

Diabetes mellitus is globally the major cause for metabolic syndrome in STZ-induced diabetic rats, leading to mortality. Treatment of diabetes by oral hypoglycemic agents causes adverse side effects and thus treatment with natural herbal drugs like swertiamarin is promising. Swertiamarin, an active compound isolated from Enicostemma littorale possesses antidiabetic activity and enhances β cell regeneration which causes reversal of diabetes.

OBJECTIVES

The present study aims at the following: (1) to evaluate antidiabetic, anti-hyperlipidaemic, activity of swertiamarin in Streptozotocin- induced diabetic rats using biomarkers. (2) To assess histopathological alterations in Pancreas, Liver, Kidney, and Heart of swertiamarin-treated STZ-induced diabetic rats and confirm cytoprotective activity of swertiamarin by Immunohistochemistry and morphometric investigations.

METHODS

Diabetes was induced intraperitoneally in male Wistar rats by Streptozotocin (STZ 50 mg/kg). After STZ-induction, hyperglycemic rats were treated with doses of swertiamarin orally (15, 25, 50 mg/kg) each for 28 days. Glibenclamide (2.5 mg/kg), a sulphonyl urea, was used as a standard drug. The glycemic control was measured by the biochemical parameter assays. Histopathology analysis of organs and immunohistochemistry of islets were carried out.

RESULTS

Our study results showed that oral administration of swertiamarin at a dosage of 15, 25, 50 mg/kg bw for 28 days resulted in a significant (p < 0.01) decrease in fasting blood glucose, HbA1c, TC, TG, LDL, and increased the levels of hemoglobin, plasma insulin, TP, body weight, and HDL levels significantly (p < 0.01) when compared to STZ-induced diabetic rats, as confirmed by immunohistochemical studies. The effect of swertiamarin on Carbohydrate-metabolizing enzymes was investigated and found to have normal therapeutic activity. Histopathological studies of Pancreas of swertiamarin-treated diabetic rats showed regeneration of islets when compared to STZ-induced diabetic rats, as confirmed by immunohistochemical studies.

CONCLUSION

Our research results clearly substantiate that swertiamarin possesses antihyperglycemic, antihyperlipidemic, cytoprotective, and immune reactivity and also a broad spectrum potential of treating diabetes and other complications related to diabetes and hence can be developed into a potent oral antidiabetic drug.

Pharmacognosy of Enicostemma littorale: a review

Traditional medicine system of India comprised varieties of plants which are playing a significant role in curing diseases from ancient times. Among them, Enicostemma littorale blume (E. littorale) a perennial herb of the family Gentianaceae is cosmopolitan in occurrence in India. The bittery natured plant acts as a laxative, helps in curing fever, rheumatism, skin diseases, abdominal disorders, snake bite, obesity and helps to regulate blood sugar levels. The plant constituents have been reported for possessing antimicrobial, antioxidant, antiulcer, antiinflammatory, hypolipidaemic, hepatoprotective and hypoglycemic properties. This review provides a bird's eye view about geographical distribution, physicochemical parameters, phytoconstituents and pharmacological properties of E. littorale.

Hypoglycemic activity of C-glycosyl flavonoid from Enicostemma hyssopifolium

CONTEXT

Enicostemma hyssopifolium Verdoon (Gentianaceae) has been documented for various therapeutic effects in traditional systems of medicine; the hypoglycemic and hypolipidemic activities are also well reported.

OBJECTIVE

Bioactivity guided fractionation of methanol extract of E. hyssopifolium to test the hypothesis that E. hyssopifolium and its constituents influence cells and systemic glucose homeostasis.

MATERIALS AND METHODS

Derived fraction and isolated compounds were studied for (1) aldose reductase (AR) inhibition, (2) α-glucosidase inhibition, (3) effect on gluconeogenesis in rat hepatoma, (4) cytoprotection against streptozotocin (STZ)-induced toxicity on RINm5F cells, (5) normalization of glycemic control in acute hyperglycemic rat model, and (6) insulin-releasing effect both in vitro and in vivo.

RESULTS

The results indicated that E. hyssopifolium can modify the glucose homeostasis at the cellular level. Two bioactive constituents were identified. Swertisin was found to inhibit AR (IC(50) 1.23 μg/mL) and α-glucosidase (IC(50) 1.89 μg/mL). It also possessed a significant cytoprotective action of RINm5F cell line against toxicant STZ. Swertiamarin was found to have hepatic gluconeogenesis inhibiting and insulin-releasing effect on rat hepatoma and RINm5F cells, respectively. The results of the in vivo study showed that swertiamarin, unlike the in vitro effect, produced no significant raise of insulin secretion. Swertisin normalized the serum glucose 60 min after high dose of glucose (2 g/kg, i.p.) in rats.

DISCUSSION AND CONCLUSION

These findings demonstrate that the fraction derived from the aerial part of E. hyssopifolium achieve normoglycemic status in hyperglycemic conditions via various mechanisms. The constituents swertiamarin and swertisin are responsible for bioactivity.

Swertia (Gentianaceae): Chemical and Pharmacological Aspects

A compilation of the constituents isolated from Swertia species covering the literature up to December 2003 is presented. The botanical classification and ethno-pharmacology of Swertia plants, as well as the biological activities and pharmacological applications of both distinct phytochemicals and medicinally active plant materials (formulations, extracts, etc.) are discussed in detail.

Effect of chronic treatment with Enicostemma littorale in non-insulin-dependent diabetic (NIDDM) rats

We have studied the effect of aqueous extract of Enicostemma. littorale (2 g/kg p.o.) daily for 6 weeks in neonatal non-insulin-dependent diabetes mellitus (NIDDM) rats. To induce NIDDM a single dose injection of STZ (70 mg/kg; i.p.) was given to the 5-day-old pups. After 3 months of STZ injection when animals were confirmed as diabetic, E. littorale was administered for 6 weeks. Fasting and fed glucose and insulin levels in NIDDM were significantly (P<0.05) higher than control rats and they were significantly decreased by the treatment with E. littorale. Results of the oral glucose tolerance test (OGTT) showed a significant (P<0.05) decrease in both AUC(glucose) and AUC(insulin) values in NIDDM treated group. Insulin sensitivity (K(ITT)) index of NIDDM control was significantly lower as compared with Wistar control and this was significantly (P<0.05) increased after treatment with E. littorale. Treatment with E. littorale also decreased the elevated cholesterol, triglyceride and creatinine levels observed in NIDDM rats. Our data suggest that aqueous extract of E. littorale is a potent herbal antidiabetic. It produces an increase in insulin sensitivity, normalizes dyslipidaemia and provides nephroprotection in diabetic rats.

Chemical constituents of gentianaceae XXVIII: flavonoids of Enicostemma hyssopifolium (Willd.) Verd

The whole plant of Enicostemma hyssopifolium (Willd.) Verd. (Gentianaceae) was collected at different growth stages and was shown to contain seven flavonoids: apigenin (I), genkwanin (II), isovitexin (III), swertisin (IV), saponarin (V), 5-O-glucosylswertisin (VI), and 5-O-glucosylisoswertisin (VII). Compounds VI and VII previously were unreported in nature. The yields of the flavonoids varied with the growth stage. The biochemical and chemotaxonomic significance of these results is appraised.