Assessment of Lemon Balm (Melissa officinalis L.) Hydrogels: Quality and Bioactivity in Skin Cells

The therapeutic potential of Melissa officinalis L. hydroalcoholic extract and rosmarinic acid in a rat asthmatic model: A study on anti-inflammatory and antioxidant effects

Objective

The article studies how Melissa officinalis L. extract and rosmarinic acid (RA) affect lung inflammation, pathology, and oxidative stress in rats with ovalbumin-induced asthma.

Materials and Methods

Asthma was induced in rats using ovalbumin injection and inhalation. The study assessed lung inflammation, pathological changes, and oxidative stress in control, untreated asthmatic rats and three treatment groups. These groups received M. officinalis extract (50, 100, 200 mg/kg), RA (0.5, 1, 2 mg/kg), or dexamethasone (Dex) 1 mg/kg.

Results

In the sensitized group, white blood cell counts, malondialdehyde, and nitrite levels increased significantly, while thiol levels and the activity of superoxide dismutase and catalase decreased (p<0.001). However, all treatment groups with the extract, RA, and Dex showed a significant reduction in total white blood cells, eosinophils, monocytes, malondialdehyde, and nitrite levels compared to the asthma group (p<0.001 in all groups). Thiol levels and catalase and superoxide dismutase activity were significantly higher in all treated groups with RA and high extract doses (p<0.001). Lung pathological changes were also significantly less severe in the treated groups with dexamethasone, plant extract, and RA compared to the asthma group (p<0.05 to p<0.001).

Conclusion

This study showed that M. officinalis and RA have antioxidant and anti-inflammatory effects in an animal asthma model, suggesting their potential for treating asthma symptoms.

Melissa officinalis extract palliates redox imbalance and inflammation associated with hyperthyroidism-induced liver damage by regulating Nrf-2/ Keap-1 gene expression in γ-irradiated rats

BACKGROUND

Melissa officinalis (MO) is a well-known medicinal plant species used in the treatment of several diseases; it is widely used as a vegetable, adding flavour to dishes. This study was designed to evaluate the therapeutic effect of MO Extract against hyperthyroidism induced by Eltroxin and γ-radiation.

METHODS

Hyperthyroidism was induced by injecting rats with Eltroxin (100 µg/kg/ day) for 14 days and exposure to γ-radiation (IR) (5 Gy single dose). The hyperthyroid rats were orally treated with MO extract (75 mg/kg/day) at the beginning of the second week of the Eltroxin injection and continued for another week. The levels of thyroid hormones, liver enzymes and proteins besides the impaired hepatic redox status and antioxidant parameters were measured using commercial kits. The hepatic gene expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its inhibitor Kelch-like ECH-associated protein-1(Keap-1) in addition to hepatic inflammatory mediators including tumor necrosis factor-α (TNF- α), Monocyte chemoattractant protein-1 (MCP-1) and fibrogenic markers such as transforming growth factor-beta1 (TGF-β1) were determined.

RESULTS

MO Extract reversed the effect of Eltroxin + IR on rats and attenuated the thyroid hormones. Moreover, it alleviated hyperthyroidism-induced hepatic damage by inhibiting the hepatic enzymes' activities as well as enhancing the production of proteins concomitant with improving cellular redox homeostasis by attenuating the deranged redox balance and modulating the Nrf2/Keap-1 pathway. Additionally, MO Extract alleviated the inflammatory response by suppressing the TNF- α and MCP-1 and prevented hepatic fibrosis via Nrf2-mediated inhibition of the TGF-β1/Smad pathway.

CONCLUSION

Accordingly, these results might strengthen the hepatoprotective effect of MO Extract in a rat model of hyperthyroidism by regulating the Nrf-2/ Keap-1 pathway.

The effect of Melissa officinalis syrup on patients with mild to moderate psoriasis: a randomized, double-blind placebo-controlled clinical trial

Objective

Psoriasis is an immune-mediated inflammatory skin disease. It can involve any body skin area, particularly the scalp, lower back, elbows, and knees. There are several topical and systemic therapies for the treatment. Nowadays, herbal medicines are popular treatments for dermatologic conditions. This two-arm parallel, randomized placebo-controlled clinical trial was conducted to examine the hypothesis of the efficacy of Melissa officinalis syrup on patients with mild-to-moderate Plaque psoriasis.

Result

Among 100 patients, 95 participants completed the trial and five of them withdrew. The mean pruritus intensity and PASI scores decreased significantly in the intervention group compared to the placebo group (P < 0.001). The DLQI score in the intervention group increased post-treatment compared to pre-treatment (P = 0.029); however, there was no significant difference between the intervention and control group at the end of the study (0.065).

Trial registration: The trial was registered in the Iranian registry of clinical trials on November 9th, 2019 (https://www.irct.ir/trial/43434; registration number: IRCT20191104045326N1).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05667-9.

Melissa officinalis L. Aqueous Extract Exerts Antioxidant and Antiangiogenic Effects and Improves Physiological Skin Parameters

Melissa officinalis (MO) is a medicinal plant well-known for its multiple pharmacological effects, including anti-inflammatory, anticancer and beneficial effects on skin recovery. In this context, the present study was aimed to investigate the in vitro and in vivo safety profile of an MO aqueous extract by assessing cell viability on normal (HaCaT-human keratinocytes) and tumor (A375-human melanoma) cells and its impact on physiological skin parameters by a non-invasive method. In addition, the antioxidant activity and the antiangiogenic potential of the extract were verified. A selective cytotoxic effect was noted in A375 cells, while no toxicity was noticed in healthy cells. The MO aqueous extract safety profile after topical application was investigated on SKH-1 mice, and an enhanced skin hydration and decreased erythema and transepidermal water loss levels were observed. The in ovo CAM assay, performed to investigate the potential modulating effect on the angiogenesis process and the blood vessels impact, indicated that at concentrations of 100 and 500 µg/mL, MO aqueous extract induced a reduction of thin capillaries. No signs of vascular toxicity were recorded at concentrations as high as 1000 μg/mL. The aqueous extract of MO leaves can be considered a promising candidate for skin disorders with impaired physiological skin parameters.

Antibiotic Delivery Strategies to Treat Skin Infections When Innate Antimicrobial Defense Fails

The epidermal skin barrier protects the body from a host of daily challenges, providing protection against mechanical insults and the absorption of chemicals and xenobiotics. In addition to the physical barrier, the epidermis also presents an innate defense against microbial overgrowth. This is achieved through the presence of a diverse collection of microorganisms on the skin (the "microbiota") that maintain a delicate balance with the host and play a significant role in overall human health. When the skin is wounded, the local tissue with a compromised barrier can become colonized and ultimately infected if bacterial growth overcomes the host response. Wound infections present an immense burden in healthcare costs and decreased quality of life for patients, and treatment becomes increasingly important because of the negative impact that infection has on slowing the rate of wound healing. In this review, we discuss specific challenges of treating wound infections and the advances in drug delivery platforms and formulations that are under development to improve topical delivery of antimicrobial treatments.

Melissa officinalis ssp. altissima extracts: A therapeutic approach targeting psoriasis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L., commonly known as lemon balm, is one of the most well known edible and medicinal plants of the Lamiaceae family. It is quoted in almost all known medical treatises, from Antiquity up to modern era, such as Corpus Hippocraticum, Dioscorides' De Materia Medica and later on in medieval medical manuscripts and Pharmacopoeias. Actually, it is widely used as herbal medicine for the relief of mild symptoms of mental stress, to aid sleep and for symptomatic treatment of mild gastrointestinal complaints including bloating and flatulence. In Greece, the empirical physicians "vikoyiatroi" recommended the decoction of dry flowers and leaves to treat tracheobronchitis, hysteria, epilepsy, heart arrhythmias, as hypnotic and against skin disorders.

AIM OF THE STUDY

The present study was conducted to investigate the potential beneficial effects in psoriasis in mice of M. officinalis ssp. altissima and to carry out the chemical analysis in order to reveal its main bioactive secondary metabolites.

MATERIALS AND METHODS

Non polar and polar extracts of M. officinalis ssp. altissima aerial parts were prepared by using dichloromethane and methanol, successively; in addition a decoction was made upon oral information by local users in Crete, where the plant was collected. All three preparations were chemically analyzed in order to isolate their main constituents. Chemical structures of all isolated compounds were determined by 1D, 2D-NMR and UV-Vis spectroscopy. Furthermore, the antioxidant potential of extracts and decoction was evaluated through DPPH radical scavenging capability. The in vivo in mice anti-psoriatic efficacy of all preparations was estimated through clinical and histopathological assessment and measurements of TEWL and hydration.

RESULTS

The dichloromethane extract yielded ursolic acid, 2α-hydroxy-ursolic acid, pomolic acid, 3β-stearyloxy-urs-12-ene, oleanolic acid, noropacursane and campesterol; the methanol extract afforded rosmarinic acid and methyl rosmarinate, while from the decoction caffeic acid, 3-(3,4-dihydroxyphenyl)lactic acid and rosmarinic acid were isolated. The psoriasis evaluation, based on PASI score, photodocumentation and histopathological estimation showed that the decoction primarily and the dichloromethane extract secondly could significantly contribute to psoriasis treatment. The decoction seems able to reestablish skin physiology by decreasing dryness and enhancing skin barrier function. Moreover, the decoction showed the best antioxidant activity, while the dichloromethane extract the weakest.

CONCLUSIONS

The triterpene derivatives of the dichloromethane extract are likely to be responsible for its anti-psoriatic activity. The abundant polyphenolic load of the decoction contributes to its high antioxidant activity and the most effective results against psoriasis. The anti-psoriatic activity of the decoction confirmed the traditional use of this plant as antioxidant, wound healing and skin barrier repair agent.

The optimization of technological processes, stability and microbiological evaluation of innovative natural ingredients-based multiple emulsion

For the last couple of decades, multiple emulsions were prepared either by the re-emulsification of primary emulsion or they were produced by an emulsion inversion and their technological peculiarities were widely investigated. The aim of our study was to investigate and determine the optimal technological parameters of innovative multiple emulsion, prepared directly-by addition of ethanolic rosemary extract in the presence of polymeric emulsifier-and evaluate its stability by experimental surface response design approach. The results revealed that simplified W/O/W emulsification process is stirring time and stirring speed sensitive: the change of stirring time from 5 to 15 min at 600 rpm resulted in increased viscosity (from 1705.6 ± 62.2 to 3364.1 ± 112.5 mPA/s) and smaller oil droplet size (from 33.09 ± 1.51 to 17.81 ± 0.78 μm), though the conductivity increased from 800 ± 2 to 882 ± 2 μS/cm (p < .05). The second mixing stage (1000 rpm) had a negative effect on the conductivity of W/O/W emulsion because of the inner aqueous phase encapsulation efficiency. Ethanolic rosemary extract was used as multifunctional agent: not only to form multiple emulsion but also to preserve it; microbiological assay confirmed its effectiveness. A stable W/O/W type drug delivery system was successfully created without additional technological stages, phase inversion or surfactants.

Testing of resveratrol microemulsion photostability and protective effect against UV induced oxidative stress

Resveratrol is well known for its antioxidant activity and susceptibility to ultraviolet radiation. Development of formulations providing improved stability and relevant drug delivery of resveratrol is still a challenging task. The aim of this study was to determine protective characteristics of formulated microemulsions by evaluating photoisomerization of resveratrol and to investigate the effects of resveratrol on human keratinocyte cells under oxidative stress caused by ultraviolet radiation. Incorporation of resveratrol into microemulsions resulted in increased photostability of active compounds and the results demonstrated that photodegradation of resveratrol was significantly delayed. Results of biopharmaceutical evaluation in vitro demonstrated that up to 60 % of resveratrol was released from microemulsions within 6 hours under a constant release rate profile. In vivo biological testing confirmed the ability of resveratrol to protect cells from oxidative stress and to increase cell viability. It was concluded that microemulsions might be considered in the development of UV light sensitive compounds.