Pharmacological activities of Asclepias curassavica L. (Apocynaceae) aerial parts.

ETHNOPHARMACOLOGICAL RELEVANCE: Asclepias curassavica L. (Apocynaceae) is a perennial shrub used in the folk treatment of parasitism, pain, and inflammation. AIM OF THE STUDY: This work assessed the antiparasitic, anti-inflammatory, antinociceptive, and sedative effects of an ethanol extract from the aerial parts of Asclepias curassavica (ACE). MATERIALS AND METHODS: The antiparasitic activity against Trichomonas vaginalis was evaluated using the trypan blue exclusion test. The in vitro anti-inflammatory actions of ACE (1-200 µg/ml) were analyzed using LPS-stimulated primary murine macrophages. The in vivo pharmacological activity of ACE (50-200 mg/kg p.o.) was evaluated using animal models of inflammation (TPA-induced ear edema test and carrageenan-induced paw edema test) and nociception (acetic acid-induced writhing test, formalin-induced licking test, and hot plate test). RESULTS: ACE showed poor antiparasitic effects against Trichomonas vaginalis (IC50 = 302 µg/ml). ACE increased the production of IL-10 in both in vitro assays (EC50 = 3.2 pg/ml) and in vivo assays (ED50 = 111 mg/kg). ACE showed good antinociceptive actions (ED50 = 158 mg/kg in phase 1 and ED50 = 83 mg/kg in phase 2) in the formalin test. Pre-treatment with naloxone blocked the antinociceptive response induced by ACE. In addition, ACE did not induce sedative effects or motor coordination deficits in mice. CONCLUSION: Findings showed that the anti-inflammatory activity of ACE is associated with increasing levels of IL-10 in both in vitro and in vivo assays, whereas the antinociceptive effect is associated with the participation of the opioidergic system, without inducing sedation or motor coordination impairment.

In vitro and in vivo anti-inflammatory effects of an ethanol extract from the aerial parts of Eryngium carlinae F. Delaroche (Apiaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Eryngium carlinae F. Delaroche (Apiaceae) is an herb used in folk medicine as a diuretic, analgesic, and anti-inflammatory agent. AIM OF THE STUDY: This work assessed the diuretic, antinociceptive, and anti-inflammatory actions of an ethanol extract from the leaves and stems of Eryngium carlinae (ECE). These ethnomedicinal properties of ECE were scientifically validated using in vitro and in vivo assays. MATERIALS AND METHODS: The antinociceptive and diuretic actions of ECE (10-200 mg/kg p.o.) were assessed with the acetic acid-induced writhing test and by using metabolic cages to house mice, respectively. The in vitro anti-inflammatory actions of ECE (1-500 µg/ml) were evaluated using LPS-stimulated primary murine macrophages, and the in vivo anti-inflammatory actions were assessed using the TPA-induced ear edema test (2 mg/ear) and carrageenan-induced paw edema test (50-200 mg/kg p.o.). The production of inflammatory mediators was estimated using in vitro and in vivo assays. RESULTS: ECE lacked antinociceptive and diuretic effects. ECE increased the production of IL-10 in LPS-stimulated macrophages (EC50 = 37.8 pg/ml) and the carrageenan-induced paw edema test (ED50 = 82.6 mg/kg). ECE showed similar in vivo anti-inflammatory actions compared to those observed with indomethacin. CONCLUSION: ECE exerts in vitro and in vivo anti-inflammatory effects by increasing the release of IL-10.

Medicinal Plants from Mexico, Central America, and the Caribbean Used as Immunostimulants.

A literature review was undertaken by analyzing distinguished books, undergraduate and postgraduate theses, and peer-reviewed scientific articles and by consulting worldwide accepted scientific databases, such as SCOPUS, Web of Science, SCIELO, Medline, and Google Scholar. Medicinal plants used as immunostimulants were classified into two categories: (1) plants with pharmacological studies and (2) plants without pharmacological research. Medicinal plants with pharmacological studies of their immunostimulatory properties were subclassified into four groups as follows: (a) plant extracts evaluated for in vitro effects, (b) plant extracts with documented in vivo effects, (c) active compounds tested on in vitro studies, and (d) active compounds assayed in animal models. Pharmacological studies have been conducted on 29 of the plants, including extracts and compounds, whereas 75 plants lack pharmacological studies regarding their immunostimulatory activity. Medicinal plants were experimentally studied in vitro (19 plants) and in vivo (8 plants). A total of 12 compounds isolated from medicinal plants used as immunostimulants have been tested using in vitro (11 compounds) and in vivo (2 compounds) assays. This review clearly indicates the need to perform scientific studies with medicinal flora from Mexico, Central America, and the Caribbean, to obtain new immunostimulatory agents.

Ethnobotany of medicinal plants used in Xalpatlahuac, Guerrero, México.

ETHNOPHARMACOLOGICAL IMPORTANCE: Medicinal plants have been used for centuries for the empirical treatment of many diseases. This study documented the use of plant species in traditional medicine in the municipality of Xalpatlahuac, Guerrero, México. MATERIALS AND METHODS: Direct interviews were performed with inhabitants from Xalpatlahuac. The interviews were analyzed with two quantitative tools: (a) the informant consensus factor (ICF) that estimates the level of agreement about which medicinal plants may be used for each category and (b) the relative importance (RI) that determines the extent of potential utilization of each species. RESULTS: A total of 67 plant species with medicinal purposes, belonging to 36 families and used to treat 55 illnesses and 3 cultural filiations were reported by interviewees. Nineteen mixtures with medicinal plants were reported by the interviewers. Mentha piperita was the most used plant for combinations (4 mixtures). The results of the ICF showed that diseases of the respiratory and digestive systems had the greatest agreement. The most versatile species according to their RI are Marrubium vulgare, Mimosa albida and Psidium guajava.. CONCLUSION: This study demonstrates that plant species play an important role in healing practices and magical-religious rituals among inhabitants from Xalpatlahuac, Guerrero, Mexico. Furthermore, pharmacological, phytochemical and toxicological studies with medicinal flora, including mixtures, are required for the experimental validation of their traditional uses.

Biological effects of aqueous extract from Turkey vulture Cathartes aura (Cathartidae) meat.

ETHNOPHARMACOLOGICAL RELEVANCE: Cathartes aura is a bird used in the Mexican traditional medicine for the empirical treatment of cancer, injuries, infections and burns. MATERIALS AND METHODS: The in vitro immunomodulatory effects of Cathartes aura extract (CAE) were evaluated estimating its effects on proliferation of human peripheral blood mononuclear cells and murine splenocytes. The effects of CAE (1-200 µg/ml) on NO production, pinocytosis and lysosomal enzyme activity were assayed in murine macrophages RAW 264.7. The cytotoxic effects of CAE (1-500 µg/ml) on tumorigenic and non tumorigenic cells were evaluated using the MTT assay. RESULTS: In the absence of LPS, CAE induced the proliferation of murine splenocytes (119%), enhanced the pinocytosis (113%) and lysosomal enzyme activity (141%) in murine macrophages with a similar potency than lypopolisaccharides 1 µg/ml. In addition, CAE exerted cytotoxic effects mainly on human cervical cancer cells (IC(50)=117 µg/ml) but lacked toxic effects on non tumorigenic cells (IC(50)>500 µg/ml). CONCLUSION: Cathartes aura exerts immunostimulatory and cytotoxic activities.

The antitumoral effect of the American mistletoe Phoradendron serotinum (Raf.) M.C. Johnst. (Viscaceae) is associated with the release of immunity-related cytokines.

ETHNOPHARMACOLOGICAL RELEVANCE: Phoradendron serotinum is commonly used in Mexican traditional medicine for the empirical treatment of cancer. However, there are no studies regarding the antitumoral or immunomodulatory activities of Phoradendron serotinum. MATERIALS AND METHODS: The in vivo toxicity of ethanolic extracts of Phoradendron serotinum (PSE) was evaluated in mice according to the Lorke procedure. The in vitro immunomodulatory effects of PSE were evaluated estimating the effects of PSE on the pinocytosis, NO production and lysosomal enzyme activity in murine macrophages RAW 264.7. The effects of PSE on the proliferation of murine splenocytes and NK cell activity were also assayed. The cytotoxic effects on TC-1 (lung murine cancer cells) were evaluated using the MTT assay, whereas the apoptotic effect of PSE on TC-1 cells was evaluated using TUNEL assay. Also, different doses of PSE were injected intraperitoneally daily into C57BL/6 mice bearing tumors of TC-1 cells during 25 days. The growth and weight of tumors was measured. In addition, the levels of IL-2, IL-6, IL-12, IL-23 and IFN-γ in murine serum and supernatants of K562 cell-murine splenocyte cocultures were measured. RESULTS: PSE stimulated the proliferation, pinocytosis and lysosomal enzyme activity in murine macrophages with a similar potency than lypopolisaccharides 1 µg/ml. In addition, PSE stimulated the proliferation of murine splenocytes and induced the NK cell activity. PSE showed cytotoxic (IC(50)=1.9 µg/ml) and apoptotic effects against TC-1 cells. The LD(50) was 125 mg/kg by intraperitoneal route (i.p.) and 375 mg/kg by oral route. PSE administrated at 1, 5 and 10 mg/kg i.p. inhibited the tumor growth by 18%, 40% and 69%, respectively, in mice bearing TC-1 tumor. PSE increased the in vitro and in vivo release of IL-2, IL-6 and IFN-γ but lacked effect on IL-12 and IL-23 release. CONCLUSIONS: Phoradendron serotinum shows moderate toxic effects in vivo, exerts cytotoxic and apoptotic effects on TC-1 cells. Phoradendron serotinum also has antitumor effects in mice bearing TC-1 tumor and induces immunomodulatory activities in vivo. The results suggest that antitumoral effects of PSE are related with the production of immunity-related cytokines.

Antitumor and immunomodulatory effects of Justicia spicigera Schltdl (Acanthaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants are an important source of antitumor compounds. This study evaluated the acute toxicity in vitro and in vivo, as well as the cytotoxic, antitumor and immunomodulatory effects of ethanolic extracts of Justicia spicigera leaves (JSE). MATERIALS AND METHODS: The in vitro and in vivo toxicity of JSE was evaluated with comet assay in peripheral blood mononuclear cells (PBMC) and acute toxicity in mice, according to the Lorke procedure, respectively. The apoptotic effect of JSE on human cancer cells and human noncancerous cells was evaluated using flow cytometry with annexin-Alexa 488/propidium iodide. Also, different doses of JSE were injected intraperitoneally daily into athymic mice bearing tumors of HeLa cells during 18 days. The growth and weight of tumors were measured. The in vitro immunomodulatory effects of JSE were evaluated estimating the effects of JSE on the phagocytosis of the yeast Saccharomyces cerevisiae, NO production and H(2)O(2) release in macrophages, as well as the proliferation of splenocytes and NK activity. RESULTS: The comet assay showed that only JSE tested at 200 and 1000 µg/ml induced a significantly DNA damage in PBMC, compared to untreated cells, whereas the LD(50) was >5000 mg/kg by intraperitoneal route (i.p.) and by oral route. JSE showed pro-apoptotic (Annexin/PI) effects by 35% against HeLa cells, but lack toxic effects against human normal cells. JSE administrated at 10, 50 and 100 mg/kg i.p. inhibited the tumor growth by 28%, 41% and 53%, respectively, in mice bearing HeLa tumor. JSE stimulated, in a concentration dependent manner, the phagocytosis of Saccharomyces cerevisiae yeasts, the NO production and H(2)O(2) release by human differentiated macrophages. In addition, JSE stimulated the proliferation of murine splenocytes and induced the NK cell activity. CONCLUSION: Justicia spicigera shows low toxic effects in vitro and in vivo, exerts apoptotic effects on HeLa cells, has antitumor effects in mice bearing HeLa tumor and induces immunomodulatory activities in vitro.