Variation in essential oil components and anti-inflammatory activity of Allophylus edulis leaves collected in central-western Brazil

Potential anti-arthritic and analgesic properties of essential oil and viridiflorol obtained from Allophylus edulis leaves in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Viridiflorol was identified and isolated from the essential oil of Allophylus edulis leaves (EOAE). A. edulis was used as "tereré", which is a drink made by the infusion of herbs in cold water, to treat pain (toothache and headache). All anti-nociceptive (analgesic) and anti-arthritic properties of EOAE and viridiflorol have not been completely scientifically clarified.

AIM OF THE STUDY

The aim of the present study was to investigate the analgesic (anti-hyperalgesic and anti-nociceptive) and anti-arthritic properties of EOAE and viridiflorol using in vivo models.

MATERIALS AND METHODS

The oral administration (p.o.) of EOAE (30, 100 and 300 mg/kg), viridiflorol (30, 100 and 200 mg/kg), morphine (1 mg/kg, subcutaneous route (s.c.)) and the intraplantar (local) administration (i.pl.) of viridiflorol (100 μg/paw) were tested using formalin model in Swiss mice. EOAE (100 mg/kg, p.o.), viridiflorol (200 mg/kg, p.o.), and dexamethasone (1 mg/kg, s.c.) were tested by zymosan-articular inflammation and in open-field models. Viridiflorol (0.3, 20 and 200 μg/paw) was also tested in carrageenan model, and viridiflorol (200 μg/paw) was also tested in tumor necrosis factor-α (TNF-α), and dopamine (DOPA) models.

RESULTS

The oral administration of EOAE (100 and 300 mg/kg, p.o.), viridiflorol (200 mg/kg, p.o.), morphine (1 mg/kg, s.c.) (MOR) and local administration of viridiflorol (100 μg/paw) significantly inhibited edema and nociception in formalin model. Oral treatments with EOAE and viridiflorol (200 mg/kg) did not cause motor impairment in the open field test since they did not reduce locomotor activity. EOAE, viridiflorol and dexamethasone significantly reduced mechanical hyperalgesia, edema, total leukocytes, polymorphonuclear cells, nitric oxide and protein exudation in the zymosan-induced articular inflammation model. The local administration of viridiflorol (200 μg/paw, i.pl.) significantly inhibited mechanical hyperalgesia and edema induced by carrageenan, TNF-α and DOPA.

CONCLUSIONS

This study confirms the potential anti-arthritic, anti-nocicepttive and anti-hyperalgesic properties of EOAE and viridiflorol. These properties could explain, at least in part, the folk use of A. edulis against including pain (toothache and headache). Viridiflorol could be partially responsible for the EOAE anti-hyperalgesic, anti-nociceptive and anti-arthritic properties and its mechanism of action could involve the inhibition of TNF-α and DOPA pathways.

Chemical Profiling, Formulation Development, In Vitro Evaluation and Molecular Docking of Piper nigrum Seeds Extract Loaded Emulgel for Anti-Aging

Emulgel is a new innovatory technique for drug development permitting controlled release of active ingredients for topical administration. We report a stable emulgel of 4% Piper nigrum extract (PNE) prepared using 80% ethanol. The PNE-loaded formulation had an antioxidant activity of 84% and tyrosinase inhibition was 82%. Prepared formulation rendered spherical-shaped globules with high zeta potential (−45.5 mV) indicative of a stable system. Total phenolic contents were 58.01 mg GAE/g of dry extract whereas total flavonoid content was 52.63 mg QE/g of dry extract. Sun protection factor for PNE-loaded emulgel was 7.512 and formulation was stable without any evidence of physical and chemical changes following 90 days of storage. Gas chromatography-mass spectroscopy (GC-MS) revealed seventeen bioactive compounds in the PNE including monoterpenoids, triterpenoids, a tertiary alcohol, fatty acid esters, and phytosterols. In silico studies of GC-MS identified compounds show higher binding affinity in comparison to standard kojic acid indicating tyrosinase inhibition. It can be concluded that PNE-loaded emulgel had prominent antioxidant and tyrosinase inhibition and can be utilized as a promising topical system for anti-aging skin formulation.

Bioassay-Guided Isolation of Anti-Inflammatory Constituents of the Subaerial Parts of Cyperus articulatus (Cyperaceae)

Based on data from a previous ethnobotanical study in northern Angola, phytochemical investigations into the methanolic rhizomes and roots extract of Cyperus articulatus, monitored by in vitro assays, resulted in the recovery of 12 sesquiterpenes, 3 stilbenes, 2 phenolic acids, 1 monoterpene, and 1 flavonoid. Among them, 14 compounds were isolated for the first time from this species. Their inhibitory potential against nitric oxide (NO) production, as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, was evaluated in LPS-treated J774A.1 murine macrophages. Especially, both stilbene dimer trans-scirpusin B and trimer cyperusphenol B showed promising inhibitory activity against the production of the inflammatory mediator, NO, in a concentration-dependent manner (10−1 µM). The obtained data are the first results confirming the anti-inflammatory potential of C. articulatus and support its indigenous use as a traditional remedy against inflammation-related disorders.

Palicourea tomentosa (Aubl.) Borhidi: Microscopy, chemical composition and the analgesic, anti-inflammatory and anti-acetylcholinesterase potential

ETHNOPHARMACOLOGICAL RELEVANCE

Palicourea tomentosa (Aubl.) Borhidi (synonym Psychotria poeppigiana Müll. Arg.) leaves are used in the popular treatments of inflammation and pain; however, there are no scientific studies demonstrating their activity as the methanolic extract of P. tomentosa.

AIM OF STUDY

This study was undertaken to investigate the potential antioxidant, anti-acetylcholinesterase, anti-hyperalgesic, anti-nociceptive and anti-inflammatory properties, as well as the chemical composition and concentrations of constituents of the methanolic extract of P. tomentosa leaves (MEPT). The study also analyzes the micromorphology and histochemistry of leaves of P. tomentosa.

MATERIALS AND METHODS

The MEPT was analysed by ultra-high-pressure liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS/MS). The concentrations of total phenols, flavonoids, flavonols and condensed tannin were determined. The micromorphology and histochemistry of leaves were performed using standard reagents, light and field emission scanning electron microscopy, beyond energy-dispersive X-ray spectroscopy. The antioxidant activity was evaluated for DPPH, β-carotene and MDA. The anti-inflammatory activity of MEPT (30, 100, and 300 mg/kg) was assayed in carrageenan-induced models of paw oedema, mechanical hyperalgesia (Von Frey), cold allodynia (acetone) and pleurisy in mice. The anti-nociceptive potential of MEPT (30, 100, and 300 mg/kg) was evaluated by the formalin method in mice. The anti-acetylcholinesterase properties were evaluated in vivo in four rat brain structures.

RESULTS

The total ion chromatogram of MEPT demonstrated two alkaloids, one coumarin, one iridoid and two terpene derivatives. The highest phenol, flavonoid, flavonol and condensed tannin concentrations were found in the extract. A comprehensive explanation of the leaf micromorphology and histochemistry was presented. MEPT was significantly inhibited by the DPPH, β-carotene and MDA models. MEPT (30, 100 and 300 mg/kg) reduced the inflammation and hyperalgesic parameters in a carrageenan model and reduced formalin-induced nociception in both phases, which were cold sensitivity and oedema formation. The oral administration of 30 and 100 mg/kg MEPT significantly inhibited AChE activity in the frontal cortex.

CONCLUSION

This is the first chemical and biological study performed with a P. tomentosa methanolic extract and anatomical and histochemical analysis. The present study showed that MEPT inhibited pain and inflammatory parameters contributing, at least in part, to explain the popular use of this plant as analgesic natural agent. Also, anatomical and histochemistry of leaves described in the present study provide microscopical information, which aids species identification.

α-zingiberene, a sesquiterpene from essential oil from leaves of Casearia sylvestris, suppresses inflammatory angiogenesis and stimulates collagen deposition in subcutaneous implants in mice

α-zingiberene is a phytochemical of the sesquiterpenes class, the major constituent of the essential oil from the leaves of Casearia sylvestris, a plant widely used in traditional medicine for the treatment of inflammatory diseases, tumours, and bacterial infections. In the present study, we evaluated the effects of daily administration of α-zingiberene (0.01, 0.1 and 1 μg diluted in 10 μl of 0.5% DMSO) on the inflammatory, angiogenic, and fibrogenic components, induced by subcutaneous sponge implants in an animal model. Treatment with sesquiterpene resulted in a reduction in macrophage activation, as well as in mean blood vessels and in the activity of metalloproteinases 2 and 9. Furthermore, it resulted in an increase in collagen deposition near the implants. These results show the therapeutic potential of α-zingiberene in the treatment of pathologies, in which processes such as inflammation and angiogenesis are exacerbated, or even for the treatment of chronic wounds.