The analgesic and anti-inflammatory effect of lawsone isolated from Lawsonia inermis

Abstract

This study aimed to assess the analgesic and anti-inflammatory effects of lawsone isolated from henna leaves (Lawsonia inermis). 
 Methods: A total of 120 healthy adult mice (weighing about 25±5 g) were included in this study. Sixty mice out of the total were used to determine LD50, 30 mice to determine the anti-inflammatory test, and the remaining (30 mice) were used for an analgesic test. The hot plate was used to determine the analgesic effect, while the anti-inflammatory effect was determined by the ability of the compound to minimize the inflammation and edema caused by the injection of carrageenan. 
 Results: Lawsone was isolated from Lawsonia inermis. A Stuart SMP10 digital melting point apparatus was used for measuring all melting points. Infrared spectrometer FT-IR 400D was used for measuring/recording IR spectra (KBr) which the frequency of absorption was represented as cm−1. For 1H-NMR spectrum recording, a Bruk-spectrophotometer of 400 MHz was used with internal TMS standard, with deuterated Ś 2.51 ppm for acetone-d6, remained solvent signals as well as 13C.NMR was used. TLC was utilized as adsorbent, UV light, or iodine-completed visualization to verify compounds' purities.
 The LD50 of the oral lawsone was 96 mg/kg, and the highest dosage that did not kill any of the experimental animals was 80 mg/kg, which was used to investigate lawsone's analgesic and anti-inflammatory effects.
 Lawsone and aspirin possessed an analgesic effect compared to the control group (p<0.0001 and p<0.001, respectively); however, lawsone induced a potent analgesic effect compared to aspirin (p<0.1). In contrast, Lawsone and aspirin exerted an anti-inflammatory effect (p<0.05) compared to the control group and were equipotent in carrageenan-induced hind paw edema.
 Conclusion: It is concluded that lawsone possesses analgesic and anti-inflammatory effects, which endorse the practical medical importance of Lawsonia inermis. The latter is widely used traditionally for these purposes own to its cost-effectiveness and safety; however, further studies are required to determine the systemic safety of lawsone

Phenolic Composition and Wound Healing Potential Assessment of Moroccan Henna (Lawsonia inermis) Aqueous Extracts

“…Its ease of application is associated with minimal pain and median cutaneous infiltration [33]. A research group evaluated the analgesic and anti-inflammatory effects of Lawsone isolated from Henna leaves (L. inermis) [31]. The results of this study unfolded that the bioactive molecule Lawsone induced a strong analgesic effect when compared to the positive control with aspirin and they concluded that Lawsone has analgesic and antiinflammatory effects, confirming the practical medical importance of the L. inermis species.…”

The effect of Henna (Lawsonia inermis) vaginal suppository combined with antibiotic therapy in the treatment of cervicitis: An RCT

“…In addition, another trial demonstrated that a topical formulation of Henna resulted in a considerable improvement in contact dermatitis symptoms (22). These properties may be due to compounds derived from Henna, such as lawsone, isoplumbagin, and lawsaritol, which have anti-inflammatory and analgesic effects (23,24).…”

An Up-to-Date Review on the Phytochemical and Pharmacological Aspects of the Lawsonia Inermis

“…However, lawsone had a stronger analgesic effect than aspirin. Lawsone and aspirin, on the other hand, had an anti-inflammatory effect in comparison to the control group and were equally effective in reducing carrageenan-induced hind paw edema (p = 0.05) (Ali et al, 2022).…”