Two new sesquiterpene lactones from Montanoa tomentosa ssp. microcephala.

Two new sesquiterpene lactones: 8alpha-(4'-acetoxymethacryloyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alpha-olide (1) and 8alpha-(2'E)-(2'-acetoxymethyl-2'-butenoyloxy)-3alpha,9beta-dihydroxy-1(10)E,4Z,11(13)-germacratrien-12,6alphaolide (2), together with the known zoapatanolide A were isolated from the aerial parts of Montanoa tomentosa Cerv. in La Llave et Lex ssp. microcephala (Sch. Bip. In K. Koch) V.A. Funk (Asteraceae). The structures of all compounds were established on the basis of 1D, 2D NMR, and EIMS analysis.

[Preparation of yuanhuacine by low pressure column chromatography].

Preparation of yuanhuacine by low pressure column chromatography gives high separation rate, short washing time and one time crystallization, which comes up to the standard published by the Ministry of Public Health. The method is simple and convenient.

[Isolation and identification of julibrotriterpennoidal lactone A from Albizia julibrissin Durazz].

Julibrotriterpennoidal lactone A was isolated from the cortex of Albizia julibrissin. Its structure (the C28----C21 lactone of, 3 beta, 16 beta, 21 beta-trihydroxy-delta 12-oleanen-28-oic acid) has been determined on the basis of spectral evidence (IR, 1HNMR, 13C NMR and MS).

Isolation and characterization of a new abortifacient protein, karasurin, from root tubers of Trichosanthes kirilowii Max. var. japonicum Kitam.

A new abortifacient protein, named karasurin, was isolated from fresh root tubers of Trichosanthes kirilowii MAXIMOWICZ var. japonicum KITAMURA (Cucurbitaceae, Japanese name: kikarasuuri) by the procedure involving acetone fractionation and ion-exchange chromatography on Toyopearlpak SP 650S. Homogeneity of Karasurin was demonstrated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, and high performance liquid chromatography (HPLC). Karasurin was a highly basic protein of pI 10.1 and the molecular weight was estimated as 28000 by SDS-polyacrylamide gel electrophoresis. Karasurin showed a strong abortion effect in pregnant mice.

The immunosuppressive activities of two abortifacient proteins isolated from the seeds of bitter melon (Momordica charantia).

Two abortifacient proteins, alpha- and beta-momorcharin, have been purified from the seeds of the bitter melon (Momordica charantia). It was found that non-cytotoxic concentrations of these plant proteins can significantly inhibit the mitogenic responses of mouse splenocytes to concanavalin A, phytohaemagglutinin and lipopolysaccharide in a dose-dependent manner. In addition, the alloantigen-induced lymphoproliferation and the in vitro generation of a primary cytotoxic lymphocyte response were severely suppressed in the presence of these proteins. In contrast, the cytolytic activity of cytotoxic lymphocytes and natural killer cells was unimpaired by in vitro exposure to momorcharin. On the other hand, a clear decrease in the functional capacity of macrophages, such as the cytostatic and phagocytic activities, was observed under similar conditions. In vivo studies have shown that single injections of nontoxic microgram amounts of momorcharin into mice resulted in a significant depression of the delayed-type hypersensitivity response as well as the humoral antibody formation to sheep red blood cells. Similarly, the thioglycollate-induced in vivo migration of macrophages was also suppressed. Interestingly, the in vivo activation of natural killer cells was not appreciably affected. Our data suggests that the observed potent immunosuppressive effect of alpha- and beta-momorcharin is unlikely to be due to direct lymphocytotoxicity or due to a shift in the kinetic parameter of the immune response.

Isolation and characterization of an immunosuppressive protein from Trichosanthes kirilowii root tubers.

An immunosuppressive protein was isolated from Trichosanthes kirilowii root tubers by a procedure involving acetone fractionation and ion exchange chromatography on CM-Sepharose. Homogeneity of the protein was demonstrated in immunoelectrophoresis, SDS-polyacrylamide gel electrophoresis, gel filtration, high performance liquid chromatography and a single NH2-terminal sequence. The protein had a molecular weight of 26,000, aspartic acid as the NH2-terminal amino acid and no cysteine or carbohydrates in its molecule. It inhibited ConA-induced transformation in lymphocytes isolated from spleens of CBA mice. The protein was also potent in inducing mid-term abortion in mice.

Flowers of Hibiscus rosa-sinensis, a potential source of contragestative agent. III: Interceptive effect of benzene extract in mouse.

In mouse, oral administration of the benzene extract of Hibiscus rosa-sinensis flowers at a dose level of 1 gm/kg body weight/day from day 5-8 of gestation led to termination of pregnancy in about 92% of the animals. The effect was associated with a significant fall in peripheral level of progesterone and increase in uterine acid phosphatase activity, as measured on day 10. The ovary exhibited signs of luteolysis, and the corpus luteal delta 5-3 beta -hydroxysteroid dehydrogenase activity decreased markedly. The interceptive effect of the extract was prevented completely by exogenous progesterone (1 mg/mouse/day) or chorionic gonadotropin (1 I.U./mouse/day) and partially (62.5%) by exogenous prolactin (500 micrograms/mouse/day). In unilaterally pregnant mouse having trauma-induced deciduomata in the sterile horn, the extract caused resorption of the fetuses, and regression of the deciduomata accompanied by reduction in weight of the ovaries. Luteolysis, may be due to interference with the luteotropic influence, and a consequent fall in plasma level of progesterone have been suggested as the plausible cause of termination of pregnancy.

Studies on the mechanisms of abortion induction by Trichosanthin.

Radix trichosanthis, an abortifacient drug of mid-gestation, is extracted from the root tuber of Trichosanthes kirilowii Maxim, Cucurbitaceae. Its purified effective principle is a basic protein of molecular weight of approximately 18,000 and is named trichosanthin. By authorization it has been proved to be very effective in abortion induction of mid-gestation, particularly effective in curing ectopic pregnancy, hydatidiform mole, and invasive mole, and it has also some therapeutic action on choriocarcinoma. From the analysis of the experimental results on its initial site of action, the morphological and functional injury of trophoblast cells of placenta and of cultures in vitro and the effect on prostaglandin synthesis, the following conclusions are drawn concerning the mechanisms of abortion induction by trichosanthin: (1) Trichosanthin exerts its action directly on the placental trophoblasts and possesses a certain degree of specificity; (2) It selectively causes the necrotic denaturation of the syncytiotrophoblasts of placental villi, which makes fragments of the disintegrated cells clumped in the blood sinus, hence the coagulation of blood and the circulation hindrance, and tissue necrosis over large areas follows. The necrosis of placental villi is the primary response, and circulation hindrance secondary; (3) Structural injuries have been reflected on the impairment of functional activities; the concentrations of HCG and steroid hormones fall rapidly below the threshold values of threatened abortion. Serious structural and functional injuries bring about destructive disturbances on the normal endocrine relationship between the mother and the fetus and on metabolic exchanges. It is further postulated that through certain unknown mechanism the synthesis of prostaglandins increases, uterine contraction is initiated and abortion ensues. In summary, trichosanthin, a plant protein discovered from Chinese medicinal herbs, is a drug effective in abortion induction and against trophoblastic neoplasms. Preliminary elucidation of the mechanisms of abortion induction by trichosanthin has afforded a basis for the clinical application with better efficacy and its possible abortifacient use in early pregnancy and for the discovery of newer cancer chemotherapeutic agents.