Pharmacological, genotoxic and phytochemical properties of selected South African medicinal plants used in treating stomach-related ailments

Okem, Ambrose; Finnie, J.F.; Staden, J. Van

doi:10.1016/j.jep.2011.11.034

Cited by 26 publications

(26 citation statements)

References 49 publications

(49 reference statements)

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“…Previous studies have shown the anti-inflammatory effects of T. riparia extract on prostaglandins, cyclooxygenase 1 (COX 1), and cyclooxygenase 2 (COX 2), but its effect on iNOS has been unknown (Ndhlala, et al, 2011, Okem, et al, 2012. In leishmaniasis, this increase in iNOS may influence the nitric oxide production and promote elimination of the parasite.…”

Section: Resultsmentioning

confidence: 99%

“…In Brazil, it is known as false myrrh, and it is mainly used as an ornamental plant and incense (Gazim, et al, 2010, Martins, 2008. Its leaves and essential oil have been used for the treatment of malaria, cryptococcosis, candidiasis, and respiratory infections (Campbell, et al, 1997, Okem, et al, 2012, van Puyvelde, et al, 1986, York, et al, 2012. Natural products are relatively inexpensive, accessible, and sustainable, and many of them do not have a high likelihood of causing serious adverse effects (Adebayo, 2013).…”

Section: Introductionmentioning

confidence: 99%

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Antileishmanial activity of essential oil and 6,7-dehydroroyleanone isolated from Tetradenia riparia

Demarchi

Thomazella

Terron

et al. 2015

Experimental Parasitology

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Tetradenia riparia plant is used as a traditional medicine in Africa for the treatment of inflammatory and infectious diseases as like parasitic. Therapy for leishmaniasis caused by Leishmania (Leishmania) amazonensis specie often fails, and the conventional drugs are toxic, expensive, require a long period of treatment, and adverse effects are common. The alternative therapies using natural products are inexpensive and have few or any adverse reaction. These reasons are sufficient to investigate the new natural therapeutic for leishmaniasis. We evaluated the potential of the essential oil (TrEO) and 6,7-dehydroroyleanone (TrROY) isolated from T. riparia on L. (L.) amazonensis promastigote and amastigote forms, cytotoxicity on human erythrocytes and murine macrophages, nitric production and inducible nitric oxide synthase (iNOS) mRNA expression. TrEO was the most effective to promote the Leishmania promastigote death. After 72 h incubation, the lethal dose of TrEO and TrROY that promoted 50% Leishmania death (LD50) were 0.8 μg/mL and 3 μg/mL, respectively. TrEO and TrROY were not cytotoxic to human erythrocytes, but TrROY was toxic to murine macrophages resulting in a low selectivity index. The transmission electronic microscopy showed that TrEO (0.03 μg/mL) was able to modify the promastigote ultrastructures suggesting autophagy as chromatin condensation, blebbing, membranous profiles and nuclear fragmentation. Infected-macrophages treated with TrEO (0.03 μg/mL) or TrROY (10 μg/mL) had an infection index decreased in 65 and 48%. TrEO did not induce iNOS mRNA expression or nitrite production in macrophages infected with Leishmania. TrROY and mainly TrEO promoted the Leishmania death, and TrROY showed loss toxicity to erythrocytes cells. Other compounds derived from T. riparia and the essential oil could be explored to develop a new alternative treatment for leishmaniasis.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Antileishmanial activity of essential oil and 6,7-dehydroroyleanone isolated from Tetradenia riparia

Demarchi

Thomazella

Terron

et al. 2015

Experimental Parasitology

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“…Its distribution also extends to Swaziland, Namibia, Angola, Uganda and tropical east Africa into Ethiopia (Codd 1985). It is mainly the leaves of Iboza that are used in the preparation of traditional remedies for the management of tuberculosis (Asiimwe et al, 2013), respiratory infections (York et al, 2012), stomach ailments (Okem et al, 2012), diarrhoea, influenza, malaria and headaches (Hutchings et al, 1996). The leaves are reported to contain various phyto-compounds such as terpenoids (Campbell et al, 1997; Van Puyvelde and de Kimpe, 1998) and pyrones (Van Puyvelde et al, 1987).…”

Section: Introductionmentioning

confidence: 99%

Green synthesis of nano-silver particles from leaf and stem extracts of <i>Iboza</i> (<i>Tetradenia riparia</i>)

Shaik¹,

Mkize²,

Khumalo³

et al. 2015

Afr. J. Trad. Compl. Alt. Med.

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Background: Secondary metabolites derived from plant extracts can be used in the reduction of metal salts into their respective nanoparticles using simple, environmentally friendly and cost effective green synthesis techniques. Metal nanoparticles have important applications in medicine and agriculture. The leaves of Tetradenia riparia (Iboza), an important medicinal species in South Africa, are reported to contain various terpenoids and pyrones which can be used in the reduction of silver nitrate (AgNO 3 ) to nano-silver particles. Materials and Methods: Fresh leaves and stems of Iboza were oven-dried, crushed, extracted in water and methanol and filtered followed by incubation with AgNO 3 . Synthesized nano-silver particles were characterised using ultraviolet visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Results:The bio-reduction of metal ion to base metal was rapidly conducted in a single step and at room temperature and pressure. UV-Vis spectra showed the characteristic surface plasmon resonance band of the synthesized nano-silver particles at 410 nm for all extracts. SEM analysis revealed predominantly aggregated spherically-shaped nano-silver particles with a size range of 20-50 nm and an average diameter of 26 nm. The presence of elemental silver in the nanoparticles was confirmed by EDX at 3 keV. As revealed by FTIR analysis, the reducing agents included terpenoids and pyrones which were responsible for reducing and capping the nano-silver particles. Conclusion: Both methanol and aqueous-derived extracts of Iboza leaves and stems can be used to synthesize nano-silver particles. FTIR evidence suggests that the reduction of the silver ions and the synthesis of the nanoparticles may have been actioned by various terpenoid and pyrone compounds found in the plant parts.

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“…Essential oils, including those of the Lamiaceae family, can stimulate cytokines that mediate the protective cellular immune response against intracellular pathogens, other agents, cancer, and autoimmune disorders . The immunomodulatory and antileishmanial effects that were induced by TrEO may be attributable to its complex mixture of compounds.…”

Section: Resultsmentioning

confidence: 99%

“…In a previous study, the EO from T. riparia presented excellent analgesic effects when administered orally in mice and inhibited acetic acid‐induced constrictions when administered intra‐abdominally . An extract of T. riparia leaves inhibited the percentage of acetyl cholinesterase, cyclooxygenase 1 (COX‐1) and COX‐2 enzymes, demonstrating an anti‐inflammatory effect . In folk medicine, T. riparia leaves are used for the treatment of respiratory illness (e.g.…”

Section: Resultsmentioning

confidence: 99%

Antileishmanial and immunomodulatory effects of the essential oil from Tetradenia riparia (Hochstetter) Codd

Demarchi

Terron

Thomazella

et al. 2015

Parasite Immunology

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Cutaneous leishmaniasis usually presents therapeutic resistance to antimonials, and the existing therapies for leishmaniasis have many adverse effects and toxicity. Natural products may be regarded as possible candidates for alternative leishmaniasis treatment. The plant Tetradenia riparia has shown promise for the treatment of infectious diseases in folk medicine. We evaluated the antileishmanial activity of an essential oil from T. riparia (TrEO) and the modulatory effects of TrEO on cytokine modulation by peritoneal fluid cells that were infected with L. (L.) amazonensis. Peritoneal fluid cells were infected with Leishmania and incubated with TrEO (30 ng/mL) for 3, 6, and 24 h. Cytokines were screened using semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and flow cytometry. Antileishmanial activity was evaluated at 24 h by microscopic counting and quantitative PCR (qPCR). TrEO treatment induced the death of 50% of Leishmania amastigotes (indicated by microscopic counting) and 91% of the parasite load (indicated by qPCR). TrEO inhibited some of the most critical cytokines for parasite growth and the establishment of infection, including granulocyte-macrophage colony-stimulating factor, interleukin-4 (IL-4), IL-10, and tumour necrosis factor. The parasite inhibited interferon-γ and IL-12, and TrEO blocked this inhibition, indicating that these cytokines are critical for activating mechanisms associated with the death and elimination of the parasite. These results suggest that TrEO may be an alternative leishmaniasis therapy when considering its antileishmanial and immunomodulatory activity.

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Pharmacological, genotoxic and phytochemical properties of selected South African medicinal plants used in treating stomach-related ailments

Cited by 26 publications

References 49 publications

Antileishmanial activity of essential oil and 6,7-dehydroroyleanone isolated from Tetradenia riparia

Antileishmanial activity of essential oil and 6,7-dehydroroyleanone isolated from Tetradenia riparia

Green synthesis of nano-silver particles from leaf and stem extracts of <i>Iboza</i> (<i>Tetradenia riparia</i>)

Antileishmanial and immunomodulatory effects of the essential oil from Tetradenia riparia (Hochstetter) Codd

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