Croton stipulaceus Kunth, a native Mexican medicinal plant with antioxidant and anti-inflammatory activities / Croton stipulaceus Kunth, planta medicinal mexicana con actividad antioxidante y antiinflamatoria

Leaves of Croton stipulaceuswere extracted (EHex, ECHCl3and EEtOH extracts) to assesstheir antioxidant potential, anti-inflammatory activity in murine models and acute toxicity. EEtOH showed the highest effect in DPPH (37.80% inhibition), FRAP (1065.00 ± 55.30 µmolFe2+) and total polyphenols (231.24 ± 9.05 meq AG/gM). EHex was the most active, ~ 50% inhibition of TPA-induced ear edema; while EEtOH (dose of 2 mg/ear) showed the highest inhibition in the chronic model (97% inhibition), and inhibited MPO activity (48%). In carrageenan-induced edema, ECHCl3(dose 500 mg/kg) was the most active. None of the extracts showed acute toxicity (LD50) at 2 g/kg (p.o.). This work is the first report that supports the traditional use of C. stipulaceusas an anti-inflammatory.

De las hojas de Croton stipulaceusse obtuvieron diferentes extractos (EHex, ECHCl3y EEtOH) evaluando el potencial antioxidante y la actividad antiinflamatoria en modelos murinos y la toxicidad aguda. El EEtOH mostró mayor efecto en DPPH (37.80% inhibición), FRAP (1065.00 ± 55.30 µmolFe2+) y polifenolestotales (231.24 ± 9.05 meq AG/gM). El EHex fue el más activo, cercano al 50% de inhibición del edema auricular inducido con TPA; mientras que el EEtOH (dosis de 2 mg/oreja) mostró la mayor inhibición en el modelo crónico (97% inhibición), e inhibió la actividad de la MPO (48%). En el edema inducido con carragenina, el ECHCl3(dosis 500 mg/kg) fue el más activo. Ninguno de los extractos mostró una toxicidad aguda (DL50) mayor a 2 g/kg (p.o). Este trabajo es el primer reporte que sustenta el uso tradicional de C. stipulaceuscomo antiinflamatorio.

Flaxseed Oil (Linum usitatissimum) Prevents Cognitive and Motor Damage in Rats with Hyperammonemia.

Hyperammonemia is characterized by the excessive accumulation of ammonia in the body as a result of the loss of liver detoxification, leading to the development of hepatic encephalopathy (HE). These metabolic alterations carry cognitive and motor deficits and cause neuronal damage, with no effective treatment at present. In this study, we aimed to evaluate the effect of two subacute oral administrations of flaxseed oil (0.26 and 0.52 mL/kg) on short- and long-term memory, visuospatial memory, locomotor activity, motor coordination, and the neuronal morphology of the prefrontal cortex (PFC) via tests on Wistar rats with hyperammonemia. The goal was to identify its role in the regulation of cerebral edema, without liver damage causing cerebral failure. In contrast with an ammonium-rich diet, flaxseed oil and normal foods did not cause cognitive impairment or motor alterations, as evidenced in the short-term and visuospatial memory tests. Furthermore, the flaxseed oil treatment maintained a regular neuronal morphology of the prefrontal cortex, which represents a neuroprotective effect. We conclude that the oral administration of flaxseed oil prevents cognitive and motor impairments as well as neuronal alterations in rats with hyperammonemia, which supports the potential use of this oil to ameliorate the changes that occur in hepatic encephalopathy.

C-Phycocyanin: A Phycobiliprotein from Spirulina with Metabolic Syndrome and Oxidative Stress Effects.

Spirulina maxima is a cyanobacterium considered a "superfood" due to its metabolites and nutrient content. These include a complex mixture of minerals, vitamins, fatty acids, proteins, and accessory pigments. In recent years, it has positioned itself as a promising source of bioactive molecules for the treatment of several diseases, including metabolic syndrome, coronary diseases, cancer, and the improvement of health modulating oxidative stress. C-Phycocyanin (C-PC) is a photosynthetic pigment from green-blue cyanobacterium and the most abundant phycobiliprotein in the Spirulina genus with various pharmacological properties attributed due to its antioxidant capacity but has no specific cellular target. This has made it a molecule of great interest in biomedical research. This review focuses on the pharmacological effects and the benefits on metabolic syndrome and oxidative stress of C-PC.

Consideraciones bioéticas para la investigación científica de plantas medicinales contra el cáncer en México / Bioethical considerations for scientific research on medicinal plants against cancer in Mexico

El presente artículo de reflexión revisa aspectos bioéticos en estudios científicos de plantas utilizadas en medicina tradicional para el tratamiento del cáncer en México. El conocimiento de las plantas medicinales documentadas en la medicina tradicional se relaciona con enfermedades como el cáncer. Esta enfermedad presenta altas tasas de mortalidad en el mundo, lo que incrementa la necesidad de nuevos fármacos para la quimioterapia. Aquí las plantas medicinales juegan un papel importante. Así, al ejecutar un estudio de plantas medicinales se deben considerar aspectos bioéticos fundamentales para la medicina tradicional como el muestreo, el estudio fitoquímico y biológico en líneas celulares de cáncer, basándose en la normatividad vigente, en estándares internacionales del Instituto Nacional del Cáncer y, principalmente, en los cuatro principios básicos de la bioética. Concluimos que es tarea de la comunidad científica avalar o desmentir el uso tradicional de las plantas medicinales para el tratamiento de enfermedades. El estudio de especies vegetales debe cumplir criterios donde la teoría, la investigación y la práctica ofrezcan soluciones a largo plazo y la protección ética de estas, del conocimiento tradicional y de los pacientes que recurren a esta alternativa.

The present reflection paper reviews bioethical aspects in scientific studies of plants used in traditional medicine for the treatment of cancer in Mexico. The knowledge of medicinal plants documented in traditional medicine is related to diseases such as cancer. This disease has high mortality rates worldwide, increasing the need for new chemotherapy drugs. Here medicinal plants play an important role. Thus, when executing a study of medicinal plants, fundamental bioethical aspects for traditional medicine such as sampling, phytochemical and biological study in cancer cell lines, based on current regulations, international standards of the National Cancer Institute and, mainly, the four basic principles of bioethics, should be considered. We conclude that it is the task of the scientific community to endorse or deny the traditional use of medicinal plants for the treatment of diseases. The study of plant species must meet criteria where theory, research and practice offer long-term solutions and the ethical protection of plant species, traditional knowledge and patients who resort to this alternative.

Antioxidant, anti-inflammatory and antinociceptive potential of Ternstroemia sylvatica Schltdl. & Cham.

OBJECTIVE: To evaluate the anti-inflammatory, analgesic, antioxidant and acute toxicity of extracts obtained from a successive extraction with solvents of ascending polarity [hexane, hex; chloroform, CHCl3 and ethanol (EtOH)] of Ternstroemia sylvatica Schltdl. & Cham. METHODS: The antioxidant potential was evaluated by 2,2 diphenyl-1-picrylhydrazyl, the ferric reducing/antioxidant power assays and by determining the total phenolic content. The anti-inflammatory and antinociceptive effects were evaluated using the in vivo croton oil-induced ear edema, phorbol 12-myristate 13-acetate induced ear edema, carrageenan-induced paw edema, acetic acid-induced writhing and formalin murine models. The acute toxicity was tested using the Lorke's method in mice. RESULTS: The EtOH extract was the most active for the antioxidant potential tests diphenyl-1-picrylhydrazyl (68.70% inhibition), ferric reducing/antioxidant power [(2431.30 ± 102.10) mmol Fe2+ and total polyphenols content (215.80 ± 8.50) meqAG/g]. The anti-inflammatory activity was evaluated by topical application of croton oil (2 mg/ear dose) where the EtOH extract showed the strongest activity compared to the control group (45.13% inhibition), whereas in the phorbol 12-myristate 13-acetate model, at the same dose, the CHCl3 extract showed the highest inhibition (42.88%). In the carrageenan induced edema model, the EtOH extract showed a stronger inhibition compared to indomethacin (56.34% and 50.70% at doses of 250 and 500 mg/kg of extract, respectively) during the first hour. Similarly, the same extract showed the highest analgesic activity (30.60% inhibition) in the acetic acid contortion assay, and in the formalin test it showed a greater effect with respect to the control group in both phases. CONCLUSIONS: Our work confirms the value of Ternstroemia sylvatica as an important anti-inflammatory and analgesic plant, whose mechanism seems to be associated to its antioxidant effects, and supports its uses in the Mexican traditional medicine.

The ethanol extract of Scutellaria baicalensis and the active compounds induce cell cycle arrest and apoptosis including upregulation of p53 and Bax in human lung cancer cells.

Despite a lack of scientific authentication, Scutellaria baicalensis is clinically used in Chinese medicine as a traditional adjuvant to chemotherapy of lung cancer. In this study, cytotoxicity assays demonstrated that crude ethanolic extracts of S. baicalensis were selectively toxic to human lung cancer cell lines A549, SK-LU-1 and SK-MES-1 compared with normal human lung fibroblasts. The active compounds baicalin, baicalein and wogonin did not exhibit such selectivity. Following exposure to the crude extracts, cellular protein expression in the cancer cell lines was assessed using 2D gel electrophoresis coupled with MALDI-TOF-MS/Protein Fingerprinting. The altered protein expression indicated that cell growth arrest and apoptosis were potential mechanisms of cytotoxicity. These observations were supported by PI staining cell cycle analysis using flow cytometry and Annexin-V apoptotic analysis by fluorescence microscopy of cancer cells treated with the crude extract and pure active compounds. Moreover, specific immunoblotting identification showed the decreased expression of cyclin A results in the S phase arrest of A549 whereas the G(0)/G(1) phase arrest in SK-MES-1 cells results from the decreased expression of cyclin D1. Following treatment, increased expression in the cancer cells of key proteins related to the enhancement of apoptosis was observed for p53 and Bax. These results provide further insight into the molecular mechanisms underlying the clinical use of this herb as an adjuvant to lung cancer therapy.

Identification of sakurasosaponin as a cytotoxic principle from Jacquinia flammea.

The crude ethanolic extract of leaves, stem-bark and roots of J. flammea were tested for their cytotoxic effect against two mammalian cell lines (HeLa and RAW 264.7) and four bacterial species (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa). When tested at the concentration of 100 microg/mL, the root extract showed the highest cytotoxic activity against mammalian cells followed by the stem-bark extract while the leaves extract did not show significant activity. No antibacterial activity was detected for all extracts when tested up to 500 microg/disc in the disc diffusion assay. The cytotoxic root extract was subjected to fractionation using solvents of ascending polarity: petroleum ether, chloroform, ethylacetate, butanol and water. The water fraction which showed cytotoxic activity was further subjected to routine bioassay-guided fraction to lead to the isolation of sakurasosaponin as the active principle. The recorded IC50 value for sakurasosaponin was 11.3 +/- 1.52 and 3.8 +/- 0.25 microM (n=3) against HeLa and RAW 264.7 respectively. The identification of sakurasosaponin was based on analysis of spectroscopic data.

Triterpenoid saponins from a cytotoxic root extract of Sideroxylon foetidissimum subsp. gaumeri.

Evaluation of the cytotoxicity of an ethanolic root extract of Sideroxylonfoetidissimum subsp. gaumeri (Sapotaceae) revealed activity against the murine macrophage-like cell line RAW 264.7. Systematic bioassay-guided fractionation of this extract gave an active saponin-containing fraction from which four saponins were isolated. Use of 1D ((1)H, (13)C, DEPT135) and 2D (COSY, TOCSY, HSQC, and HMBC) NMR, mass spectrometry and sugar analysis gave their structures as 3-O-(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, 3-O-beta-D-glucopyranosyl-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, 3-O-(beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, and the known compound, 3-O-beta-D-glucopyranosyl-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-protobassic acid. Two further saponins were obtained from the same fraction, but as a 5:4 mixture comprising 3-O-(beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid and 3-O-(beta-D-apiofuranosyl-(1-->3)-beta-D-glucopyranosyl)-28-O-(alpha-L-rhamnopyranosyl-(1-->3)[beta-D-xylopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, respectively. This showed greater cytotoxicity (IC(50)=11.9+/-1.5 microg/ml) towards RAW 264.7 cells than the original extract (IC(50)=39.5+/-4.1 microg/ml), and the saponin-containing fraction derived from it (IC(50)=33.7+/-6.2 microg/ml).