Structure--activity relationships of the estrogenic sesquiterpene ester ferutinin. Modification of the terpenoid core

Structure-Activity Studies of 1H-Imidazo[4,5-c]quinolin-4-amine Derivatives as A3 Adenosine Receptor Positive Allosteric Modulators

We previously reported 1H-imidazo[4,5-c]quinolin-4-amines as A3 adenosine receptor (A3AR) positive allosteric modulators (PAMs). A3AR agonists, but not PAMs, are in clinical trials for inflammatory diseases and liver conditions. We synthesized new analogues to distinguish 2-cyclopropyl antagonist 17 (orthosteric interaction demonstrated by binding and predicted computationally) from PAMs (derivatives with large 2-alkyl/cycloalkyl/bicycloalkyl groups). We predicted PAM binding at a hydrophobic site on the A3AR cytosolic interface. Although having low Caco-2 permeability and high plasma protein binding, hydrophobic 2-cyclohept-4-enyl-N-3,4-dichlorophenyl, MRS7788 18, and 2-heptan-4-yl-N-4-iodophenyl, MRS8054 39, derivatives were orally bioavailable in rat. 2-Heptan-4-yl-N-3,4-dichlorophenyl 14 and 2-cyclononyl-N-3,4-dichlorophenyl 20 derivatives and 39 greatly enhanced Cl-IB-MECA-stimulated [35S]GTPγS binding Emax, with only 12b trending toward decreasing the agonist EC50. A feasible route for radio-iodination at the p-position of a 4-phenylamino substituent suggests a potential radioligand for allosteric site binding. Herein, we advanced an allosteric approach to developing A3AR-activating drugs that are potentially event- and site-specific in action.

Access to Natural Valparanes and Daucanes: Enantioselective Synthesis of (-)-Valpara-2,15-diene and (+)-Isodaucene

The first total synthesis of a natural diterpene valparane, (-)-valpara-2,15-diene (1), has been achieved from all -trans-geranylgeraniol (9), a natural renewable compound. The key steps involve a Ti(III)-mediated radical cyclization of the chiral monoepoxypolyene (14 R,15 R)-14,15-epoxy,16- tert-butyldimethylsilyloxygeranyllinalyl acetate (8) to give the 6,6,7-tricyclic intermediate 7 with stereocontrolled formation of six stereocenters; a stereo- and regio-directed contraction of the A ring in 7 to produce a cyclopentane ring; and the ready generation of the target isopropenyl group. This research provides access to structurally related natural products such as the sesquiterpene (+)-isodaucene (3), the synthesis of which is also reported herein.

Recent Advances on Bioactive Constituents in Ferula

Preclinical Research The genus Ferula (Umbelliferea) is widely distributed across Central Asia and the Mediterranean. Some plants of the genus Ferula have been used as sources of pharmaceuticals for centuries. Ferula is a rich source of biologically active compounds, including coumarin derivatives, sesquiterpene-substituted compounds, daucane esters, humulane, and germacrane compounds, aromatic lactones and disulfide compounds. Therefore, utilizing these bioactive constituents with antimicrobial and insecticidal effects not only can provide a new strategy for developing drug and green pesticide, but also protect endangered plant resources. In the present review, research advances on the bioactive constituents of the genus Ferula the plant sources. Drug Dev Res 78 : 321-331, 2017. © 2017 Wiley Periodicals, Inc.

Natural Products from Chinese Medicines with Potential Benefits to Bone Health

Osteoporosis is a progressive, systemic bone disorder characterized by loss of bone mass and microstructure, leading to reduced bone strength and increased risk of fracture. It is often associated with reduced quality of life and other medical complications. The disease is common in the aging population, particularly among postmenopausal women and patients who receive long-term steroidal therapy. Given the rapid growth of the aging population, increasing life expectancy, the prevalence of bone loss, and financial burden to the healthcare system and individuals, demand for new therapeutic agents and nutritional supplements for the management and promotion of bone health is pressing. With the advent of global interest in complementary and alternative medicine and natural products, Chinese medicine serves as a viable source to offer benefits for the improvement and maintenance of bone health. This review summarizes the scientific information obtained from recent literatures on the chemical ingredients of Chinese medicinal plants that have been reported to possess osteoprotective and related properties in cell-based and/or animal models. Some of these natural products (or their derivatives) may become promising leads for development into dietary supplements or therapeutic drugs.

Is the chronic use of Ferula harmonis to enhance mice erectile function effective and safe? A histopathological study

Many studies are aimed towards a solution for erectile dysfunction which is a worldwide health problem. Medicinal and natural herbal medications have been prescribed but their long-term effects are not well known. This study aimed to investigate the impact of the chronic administration of F. hermonis root extract on the structure of the male mice reproductive organs and their fertility and to study the possible protective role of vitamin C. Sixty male albino mice were divided into 3 groups: the control, the experimental group that received F. hermonis root extract orally (6 mg/kg) for six weeks, and the treated group that received F. hermonis plus vitamin C for six weeks. Serum testosterone level and mice fertility were assessed. At the end of the experiment mice were sacrificed; testis, epididymis, and seminal vesicle were dissected and processed for routine histopathological and immunohistochemical examination. The chronic administration of F. hermonis extract significantly decreased the level of testosterone and partially impaired fertility. Histopathological degenerative changes and a significant reduction in estrogen receptor (ER)β expression were observed in testes, epididymis, and seminal vesicle. Vitamin C administration did not completely protect the testis from these harmful effects. Although F. hermonis roots are recommended to improve erectile and fertility problems, it should be used for short periods and with extreme caution. Further clinical studies to assess safety and efficacy are needed.

Ferutinin induces in vitro eryptosis/erythroptosis in human erythrocytes through membrane permeabilization and calcium influx

Ferutinin, isolated from the root of Ferula hermonis and proposed to be used as an antiosteoporosis phytoestrogen, has death promoting activities in a number of cancer cells. However, the effect of ferutinin on the induction of apoptosis in human red blood cells (RBCs), also known as eryptosis or erythroptosis, remains unclear. Given that ferutinin is a small molecule that can induce apoptosis in the cancer cells by opening the mitochondrial permeability transition pores, we therefore hypothesized that the effect of ferutinin to elicit apoptosis in human RBCs devoid of mitochondria would be minimal. This study tried to determine the in vitro effect of ferutinin on the induction of apoptosis in human RBCs. Eryptosis/erythroptosis after ferutinin treatment was examined for phosphatidylserine (PS) externalization, calcein leakage, and other apoptotic feature events by flow cytometry and confocal microscopy. Contrary to our prediction, ferutinin caused eryptosis/erythroptosis in human RBCs and simultaneously increased caspase-3 activity and the cytosolic free Ca(2+) ion level ([Ca(2+)]i). Yet, Ca(2+) seems not to be the sole mediator in ferutinin-mediated eryptosis/erythroptosis because depletion of the external Ca(2+) could not eliminate the apoptotic effect from ferutinin. Subsequent replenishment of the external Ca(2+) was able to promote PS externalization, caspase-3 activation, and rise of [Ca(2+)]i. Also, ferutinin at high dose (40 μM or above) was able to permeabilize the membrane of RBC ghosts in a way similar to that of digitonin. At low dose, ferutinin activated the P- and L-type Ca(2+) channels as the ferutinin-mediated [Ca(2+)]i rise was suppressed by the P-type (ω-agatoxin IVA) and L-type (verapamil and diltiazem) Ca(2+) channel blockers. Taken together, we report here for the first time that ferutinin induces in vitro apoptosis in human RBCs. Mechanistically, eryptosis/erythroptosis is mediated by membrane permeabilization and upregulation of [Ca(2+)]i with the activation of caspase-3.

The phytoestrogen ferutinin improves sexual behavior in ovariectomized rats

The present study was designed to examine the effect of ferutinin chronic administration on sexual behavior of ovariectomized non-estrogen-primed rats. Starting from 3 weeks after ovariectomy, female rats were orally treated with ferutinin at the doses of 0.2 and 0.5 mg/kg, daily for 4 weeks. Ferutinin's effect was compared with that of estradiol benzoate, subcutaneously injected at the dose of 1.5 microg/rat twice a week. Animals were tested for sexual motivation, receptivity and proceptivity after 1, 2 and 3 weeks of treatment and for paced mating behavior after 4 weeks of treatment. Before each experimental test, they received progesterone injection (500 microg/rat). Both dosages of ferutinin significantly increased the receptive behavior in a time-dependent manner, as well as estradiol benzoate did. Also proceptive behaviors increased in ferutinin-treated animals in comparison with control ones. During the partner preference test ferutinin was able to induce a significant preference for a sexually active male over a sexually receptive female. Moreover, ferutinin restored a normal paced mating behavior, which had been suppressed by ovariectomy. These results show that ferutinin exerts an estrogenic activity in ovariectomized non-estrogen-primed female rats.

The phytoestrogen ferutinin affects female sexual behavior modulating ERalpha expression in the hypothalamus

This study was designed to assess the effect of the phytoestrogenic compound ferutinin, chronically administered in ovariectomized progesterone primed rats, alone or in combination with estradiol benzoate. After 2, 3 and 4 weeks of treatments, female rats were tested for receptive (lordosis) and proceptive behaviors (hops, darts and ear wigglings). Ferutinin given alone markedly increased the intensity of the lordotic response in ovariectomized rats but failed to significantly affect proceptivity. On the other hand estradiol benzoate significantly increased both receptive and proceptive behaviors. When administered in combination with estradiol, ferutinin reduced the increase in receptivity and proceptivity due to estrogen effects, acting as an antiestrogen. At the end of the behavioral experiments, animals were sacrificed and Western blot analysis of estrogen receptor alpha (ERalpha) levels was performed in the dissected hypothalami. Ferutinin increased ERalpha expression when administered alone, as estradiol did, but decreased the response to estradiol when administered in combination. These results suggest that ferutinin displays estrogenic or antiestrogenic activity through ERalpha in the hypothalamus, depending on the absence or the presence of estrogen priming.

Role of ferutinin in the impairment of female sexual function induced by Ferula hermonis

In the present study, we evaluated the effects of single components of Ferula hermonis extract on female rat sexual behaviour. Ovariectomized rats hormonally primed with estradiol benzoate (1.5 or 10 microg/rat s.c.) and progesterone (500 microg/rat s.c.) were acutely treated by oral gavage with ferutinin, teferin and teferdin (2.5 mg/kg). Thereafter they were tested for: a) partner preference, b) receptivity, c) proceptivity, d) paced mating behaviour. In the partner preference test, the choice of the female for a sexually active male was not influenced by the different treatments. Similarly, during the paced mating test, the contact-return latencies as well as the percentage of exits from the male compartment were not different in control and treated rats. Therefore none of the three compounds showed the capacity to alter sexual motivation. On the other hand, ferutinin, but not teferin and teferdin, significantly inhibited female receptivity. These results suggest a primary role of ferutinin in the impairment of sexual behaviour elicited by F. hermonis extract in hormone primed-female rats.

Ferula hermonis impairs sexual behavior in hormone-primed female rats

The influence of Ferula hermonis root extract on sexual behavior was studied in female rats. Sexual receptivity, proceptivity and paced mating behavior were evaluated in ovariectomized females primed with estradiol benzoate (EB) and progesterone (P) and then treated with F. hermonis extract acutely (30 and 60 mg/kg) or subchronically (1 and 10 mg/kg daily for 10 consecutive days). A significant reduction in lordosis responses was observed in rats after acute (60 mg/kg) or subchronic (1 and 10 mg/kg) administration of the plant extract. Similarly, a decrease in proceptive behaviors was exhibited by F. hermonis treated rats in comparison with EB+P controls. No difference was found in the patterns of paced mating behavior between control and treated animals. The present results demonstrate that the acute or repeated ingestion of F. hermonis specifically impairs the receptive and proceptive components of female sexual behavior. The effect could be the consequence of an antiestrogenic action of the extract in hormone-primed female rats.