Antinociceptive and Anti-inflammatory Effects of Triterpenes from Pluchea quitoc DC. Aerial Parts

Origin differentiation based on volatile constituents of genuine medicinal materials Quisqualis indica L. via HS-GC-MS, response surface methodology, and chemometrics

INTRODUCTION

Quisqualis indica L. (QIL) has a long history as a traditional Chinese herb in China, but the study of volatile components in QIL from different geographical sources has been relatively rare.

OBJECTIVES

To establish an optimal headspace gas chromatography-mass spectrometry (HS-GC-MS) method to comprehensively analyse the volatile component profile and screen quality markers of QIL from different origins.

METHODS

Response surface methodology (RSM) was used to optimise the conditions for headspace analysis. The volatile components of QIL from four main origins of southwest China were analysed and identified by HS-GC-MS. The similarity of all samples of QIL was evaluated by fingerprint. The differences of the volatile components in QIL from different origins were distinguished by chemometrics.

RESULTS

According to the optimal conditions of RSM, a total of 31 volatile components were identified, including fatty acids, aldehydes, alcohols, alkyl pyrazines, and other volatile components. Similarity evaluation presented that there were 26 common volatile components with different contents in all samples. Principal component analysis (PCA) showed that QIL from four different origins could be roughly divided into four categories. Hierarchical cluster analysis (HCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) indicated that QIL from different origins had obvious regional characteristics.

CONCLUSION

The optimised HS-GC-MS method provided a strategy to rapidly, effectively, and accurately elucidate the volatile component profile of QIL from different origins, and seven important differential components were screened for quality evaluation and origin traceability.

<p>Anti-Nociceptive and Anti-Inflammatory Activity of <em>Hygrophila schulli</em> Leaves</p>

Purpose

The management of pain and inflammation with non-steroidal anti-inflammatory drugs and opioid analgesics are currently encountering severe adverse reactions. To overcome these problems, herbal remedies may offer new alternative medicines. Hygrophila schulli is a medicinal plant traditionally used for the treatment of pain and inflammation-related disorders; yet, these claims are not scientifically validated. Hence, this study was aimed to validate the traditional use of Hygrophila schulli leaves as anti-inflammatory and analgesic remedy.

Methods

In vitro anti-hyaluronidase assay and in vivo carrageenan-induced hind paw oedema model were used to evaluate the anti-inflammatory property of ethanolic leaf extract of Hygrophila schulli. Tail immersion and acetic acid-induced writhing tests were performed to determine the central and peripheral analgesic activity of the leaf extract, respectively.

Results

The ethanolic leaf extract exhibited significant anti-hyaluronidase activity (P<0.001) and significant inhibition of carrageenan-induced paw oedema (P<0.05) compared to untreated controls. Similarly, the extract significantly prolonged the reaction time of mice (P<0.05) for the hot-water stimuli. Furthermore, an oral dose of the extract showed significant inhibition (P<0.01) of acetic acid-induced abdominal contractions of mice. Besides, the ethanolic leaf extract did not cause any obvious sign of acute toxicity at a single oral dose of 2 g/kg.

Conclusion

The findings of this study may partially support the acclaimed traditional use of Hygrophila schulli leaves for the treatment of pain and inflammatory conditions.

Antinociceptive Activity of Petroleum Ether Fraction of Clinacanthus nutans Leaves Methanolic Extract: Roles of Nonopioid Pain Modulatory Systems and Potassium Channels

Methanolic extract of Clinacanthus nutans Lindau leaves (MECN) has been reported to exert antinociceptive activity. The present study aimed to elucidate the possible antinociceptive mechanisms of a lipid-soluble fraction of MECN, which was obtained after sequential extraction in petroleum ether. The petroleum ether fraction of C. nutans (PECN), administered orally to mice, was (i) subjected to capsaicin-, glutamate-, phorbol 12-myristate 13-acetate-, bradykinin-induced nociception model; (ii) prechallenged (intraperitoneal (i.p.)) with 0.15 mg/kg yohimbine, 1 mg/kg pindolol, 3 mg/kg caffeine, 0.2 mg/kg haloperidol, or 10 mg/kg atropine, which were the respective antagonist of α 2-adrenergic, β-adrenergic, adenosinergic, dopaminergic, or muscarinic receptors; and (iii) prechallenged (i.p.) with 10 mg/kg glibenclamide, 0.04 mg/kg apamin, 0.02 mg/kg charybdotoxin, or 4 mg/kg tetraethylammonium chloride, which were the respective inhibitor of ATP sensitive-, small conductance Ca2+-activated-, large conductance Ca2+-activated-, or nonselective voltage-activated-K+ channel. Results obtained demonstrated that PECN (100, 250, and 500 mg/kg) significantly (P<0.05) inhibited all models of nociception described earlier. The antinociceptive activity of 500 mg/kg PECN was significantly (P<0.05) attenuated when prechallenged with all antagonists or K+ channel blockers. However, only pretreatment with apamin and charybdotoxin caused full inhibition of PECN-induced antinociception. The rest of the K+ channel blockers and all antagonists caused only partial inhibition of PECN antinociception, respectively. Analyses on PECN's phytoconstituents revealed the presence of antinociceptive-bearing bioactive compounds of volatile (i.e., derivatives of γ-tocopherol, α-tocopherol, and lupeol) and nonvolatile (i.e., cinnamic acid) nature. In conclusion, PECN exerts a non-opioid-mediated antinociceptive activity involving mainly activation of adenosinergic and cholinergic receptors or small- and large-conductance Ca2+-activated-K+ channels.