Effects of Melissa officinalis (lemon balm) consumption on serum lipid profile: a meta-analysis of randomized controlled trials

BACKGROUND

According to traditional medicine, Melissa officinalis L., (lemon balm) has been known to remove harmful substances from the blood and is considered a cardiac tonic. Therefore, its use as a cardiovascular remedy may explain the lipid-lowering effects of lemon balm. Dyslipidemia can be considered as a significant preventable risk factor for atherosclerosis, coronary heart disease and type 2 diabetes. The present study is the first meta-analysis to investigate the effects of M. officinalis administration on serum levels of high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), triglyceride (TG) and total cholesterol (TC).

METHODS

From inception to October 2023, a thorough search through literature was conducted using PubMed, Scopus, and Web of Science. The inclusion criteria of this study were randomized controlled trials, with or without blinding which provided adequate data for each group at the beginning and end of the follow-up period. Meta-analysis was performed on randomized controlled trials using Comprehensive Meta-Analysis (CMA) V4 software. Risk of bias in the selected studies was examined according to the revised Cochrane risk-of-bias tool for randomized trials. Begg's funnel plot symmetry status, Begg's rank correlation, and Egger's weighted regression tests were employed to evaluate potential publication bias.

RESULTS

The meta-analysis comprised of 5 randomized controlled trials with a total of 302 patients. The findings of the meta-analysis indicated that the consumption of lemon balm had a significant decrease in TG (SMD (95% CI): -0.396(-0.620, -0.173), p-value = 0.001), TC (SMD (95% CI): -0.416 (-0.641, -0.192), p-value < 0.001) and LDL (SMD (95% CI): -0.23(-0.45, -0.008), p < 0.05) levels compared to the placebo group. While it had no statistically significant effect on HDL level (SMD (95% CI): 0.336(-0.091, 0.767), p-value = 0.123). No significant and detectable publication bias was found in the meta-analysis. Additionally, all included clinical studies demonstrated a low risk of bias for missing outcome data and selection of the reported results. The robustness of the results was demonstrated by a sensitivity analysis using the one-study remove method.

CONCLUSIONS

The findings of this meta-analysis provide evidence that lemon balm may be administered as a safe and beneficial herbal medicine for reducing TC, TG and LDL levels. According to the pooled results of 5 studies with a total of 302 patients, lemon balm intake had no significant effect on HDL level. This study reinforces the notion that lemon balm may have a substantial impact on serum lipid profile as a potential remedy in cases of dyslipidemia. The main concern of our research is the limited number of eligible studies and the relatively small population size of each individual study. The patients of these studies had different types of diseases and metabolic syndromes. However, the meta-analysis was sufficiently powered to detect the considerable effects of lemon balm in the combined population regardless of type of diseases.

(lemon balm) in acute and chronic pain models

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L. (Lamiaceae) is a medicinal plant native to Mediterranean regions and found in other parts of the world. Extracts and essential oil from this widely cultivated culinary medicinal herb are used in traditional medicine to manage a variety of disorders that include epilepsy and pain.

AIM OF THE STUDY

To assess the anti-nociceptive potentials of Melissa officinalis essential oil (MO) and probe the involvement of adrenergic, opioidergic, serotonergic and potassium adenosine triphosphate (KATP) mechanisms in its anti-nociceptive effects.

MATERIAL AND METHODS

We employed formalin-, acetic acid and hot plate-induced nociception to study the acute anti-nociceptive effects of MO. The sciatic nerve injury (CCI) model of neuropathic pain was utilized to study the anti-nociceptive effects of MO on chronic pain. Effects of MO on anxiety, cognitive deficits, oxidative stress and inflammation in the CCI rats were evaluated on elevated plus maze, open field test, novel object recognition, oxidative stress parameters and pro-inflammatory cytokines, respectively. The possible mechanism(s) of MO's anti-nociceptive effects were elucidated using prazosin, yohimbine, propranolol, glibenclimide, naloxone and metergoline, which are acknowledged antagonists for α1-, α2- and β-adrenergic, potassium adenosine triphosphate (KATP), opioidergic and serotonergic systems, respectively.

RESULTS

MO significantly attenuated acetic acid- and formalin-induced nociception; prolonged the mean reaction time of rats on hot plate before and following sciatic nerve chronic injury (CCI). MO ameliorated anxiety, cognitive deficits and oxidative stress, reduced pro-inflammatory cytokine levels and produced a near total restoration of injured sciatic nerves in CCI rats. Naloxone, metergoline and glibenclimide significantly blocked, while prazosin, yohimbine and popranolol failed to block the anti-nociceptive effects of MO in formalin-induced nociception.

CONCLUSIONS

MO contains biologically active compounds with potential anti-nociceptive properties that modulate KATP, opioidergic and serotonergic pathways. These support the development of bioactive compounds from MO as anti-nociceptive agents.

The effects of melissa officinalis on depression and anxiety in type 2 diabetes patients with depression: a randomized double-blinded placebo-controlled clinical trial

BACKGROUND

Depression is more common in diabetic patients, with a 1.5-fold increased risk of death.Melissa officinalis (M. officinalis) have anti-diabetic and anti-depression activities. The study aimed to determine the efficacy of M. officinalis extract on depression, anxiety, and sleep quality in patients with type 2 diabetes with depressive symptoms.

METHODS

In this double-blind clinical trial, 60 volunteer patients (age range 20-65 years) with type 2 diabetes mellitus with symptoms of depression were randomized into the intervention (received 700 mg/day hydroalcoholic extract; n = 30) or control group (received 700 mg/day toasted flour; n = 30). Dietary intake, physical activity, anthropometric indices, FBS (Fasting blood sugar), hs-CRP(High-sensitivity C-reactiveprotein), depression, anxiety, and sleep quality were determined at the beginning and end of the study. Depression and anxiety were assessed by Beck Depression Inventory-II (BDI-II) and Beck Anxiety Inventory (BAI), respectively; sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Sixty participants received M. officinalis extract or placebo, of which 44 patients completed the 12-week double-blind clinical trial. After 12-week the mean change of depression and anxiety scores were statistically significant between the two groups (p < 0.001 and p = 0.04, respectively), but no significant differences were observed in FBS, hs-CRP, anthropometric indices, sleep quality, and blood pressure.In the intervention group, there was a significant decrease in depression and anxiety severity(p < 0.001 and p = 0.01, respectively) at the end of the study compared to the baseline.

TRIAL REGISTRATION

All protocols in this study were followed in accordance with the Helsinki Declaration (1989 revision). Ethical approval for this study was obtained from the Iran University of Medical Sciences Ethics committee (IR.IUMS.FMD.REC 1396.9413468004; research.iums.ac.ir). The study was registered at the Iranian Registry of Clinical Trials (IRCT201709239472N16); Registration date: 09/10/2017.

Antithrombotic potential of Lippia alba: A mechanistic approach

ETHNOPHARMACOLOGICAL RELEVANCE

Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson is traditionally used in Brazil as an adjunct in the relief of mild anxiety, as an antispasmodic, and as an antidyspeptic. This medicinal species was included in the Phytotherapeutic Form of the Brazilian Pharmacopeia 2nd edition (2021) and has already been described as the most used medicinal plant in a study with patients from an Anticoagulation Clinic in Brazil. Meanwhile, no studies were found that support the safety of the use of L. alba in patients using anticoagulants, a drug with several safety limitations.

AIM OF THE STUDY

Provide scientific evidence to ensure the safety of the concomitant use of L. alba and warfarin and support the management of these patients by evaluating its in vitro anticoagulant effect and chemical composition. And, as a timely complementation, evaluate the potential of this medicinal species in the development of new antithrombotics.

METHODS

The chemical profile of L. alba derivatives was analyzed by chromatographic methods such as Ultra-Performance Liquid Chromatography (UPLC) coupled with electrospray ionization mass spectrometry (ESI-MS), qualitative UPLC using Diode-Array Detection, and Thin Layer Chromatography. The anticoagulant activity was evaluated by the innovative Thrombin Generation Assay by Calibrated Automated Thrombogram method and using traditional coagulometric tests: prothrombin time, activated partial thromboplastin time, and plasma fibrinogen measurement.

RESULTS

Extracts and fractions prolonged the coagulation time in all the tests and reduced thrombin formation in thrombin generation assay. Coagulation times with the addition of ethanloic extract (2.26 mg/mL) was 17.78s, 46.43s and 14.25s respectively in prothrombin time, activated partial thromboplastin time and fibrinogren plasma measurement. In thrombin generation test, this same extract showed ETP as 323 nM/min compared to control (815 nM/min) with high tissue factor and 582 nM/min compared to control (1147 nM/min) using low tissue factor. Presence of flavonoids, phenylpropanoids, and triterpenes were confirmed by chromatographic methods and 13 compounds were identified by UPLC-ESI-MS. Based on these results and on the scientific literature, it is possible to propose that phenylpropanoids and flavonoids are related to the anticoagulant activity observed.

CONCLUSION

The results demonstrate the in vitro anticoagulant activity of L. alba, probably due to the activation of intrinsic and extrinsic pathways. It is concluded, then, that there is a potential for interaction, which needs to be further studied, between L. alba and warfarin. Also, this medicinal species shows a great potential for use in the development of new antithrombotics.

Nip it in the Bud: Botanicals for Anxiety - a Practical Prescriber's Guide

PURPOSE OF REVIEW

The goal of this paper is to summarize the evidence for the use of botanical medicines for the treatment of anxiety disorders. We sought to make this review practical for psychiatrists and psychiatric prescribers.

RECENT FINDINGS

In 2018, the Natural Medicines database produced a Clinical Management of Anxiety guide that summarized the conventional and natural treatments of anxiety disorders. Based on this guide, four herbal supplements (also referred to as botanicals) were selected for deeper study including kava, lavender, lemon balm and passionflower. All four were considered possibly safe and possibly effective according to the Natural Medicines database. There is scientific evidence supporting the use of kava, lavender, lemon balm and passionflower in anxiety disorders. Lavender appears to have the best available evidence including comparable efficacy to conventional first line treatments and is available in a patented form that was used in the cited studies (Silexan).

Lemon balm (Melissa officinalis L.) essential oil and citronellal modulate anxiety-related symptoms - In vitro and in vivo studies

ETHNOPHARMACOLOGICAL RELEVANCE

Besides psyche-related symptoms, patients with anxiety disorders can have a large number of somatic symptoms as well. Although the treatment of these disorders is mainly focused on resolving their mental component, one cannot neglect the need for the treatment of accompanying somatic symptoms. Melissa officinalis L. (lemon balm), in various formulations, has been extensively used as an ethnomedicinal remedy for the treatment of different psyche-related symptoms, and its use is considered relatively safe.

AIM OF THE STUDY

In the present study, the activity of M. officinalis (MO) essential oil was evaluated in several in vitro and in vivo models mimicking or involving anxiety-related somatic symptoms.

MATERIALS AND METHODS

To address the effect of MO essential oil on the gastrointestinal and heart-related symptoms accompanying anxiety disorders, in vitro models were utilized that follow the function of the isolated mouse ileum and atria tissues, respectively, after exposure to MO essential oil. Effects of MO essential oil on BALB/c mice motor activity was estimated using the open field, rota-rod, and horizontal wire tests. Additionally, the essential oil was assayed for its potential in inhibiting acetylcholinesterase activity.

RESULTS

The performance of mice treated with 25 mg/kg of the oil showed a statistically significant decrease in the motor impairment arising from acute anxiety (open field test), while there was a prolonged latency and a reduction of the frequency of falling from a rotating rod and/or a horizontal wire (signs of muscle weakness/spasms). Concentrations of the essential oil higher than 1 μg/mL were found to inhibit both spontaneous and induced ileum contractions. Moreover, the essential oil and citronellal were found to decrease isolated mouse atria contraction frequency, as well as contraction force. However, the oil was found to be a very weak acetylcholinesterase inhibitor.

CONCLUSION

The modulation of anxiety-related symptoms by the oil was found not to be mediated through the inhibition of the acetylcholinesterase, nonetheless, the mechanistic studies involving the ileum and cardiac tissues, revealed that the activity of MO and citronellal might be related to the modification of either voltage-gated Ca²⁺ channels or muscarinic receptors. Mice locomotion, balance, and muscle strength were not impacted by the essential oil; however, its main constituent, citronellal, was found to exert a certain degree of muscle function inhibition. All these results suggest that the activity of MO essential oil arises from synergistic and/or antagonistic interactions of its constituents, and is not completely dependent on the oil's main constituent.

Melissa officinalis L. ameliorates oxidative stress and inflammation and upregulates Nrf2/HO-1 signaling in the hippocampus of pilocarpine-induced rats

Epilepsy is characterized by recurrent epileptic seizures, and its effective management continues to be a therapeutic challenge. Oxidative stress and local inflammatory response accompany the status epilepticus (SE). This study evaluated the effect of Melissa officinalis extract (MOE) on oxidative stress, inflammation, and neurotransmitters in the hippocampus of pilocarpine (PILO)-administered rats, pointing to the involvement of Nrf2/HO-1 signaling. Rats received PILO via intraperitoneal administration and were treated with MOE for 2 weeks. MOE prevented neuronal loss; decreased lipid peroxidation, Cox-2, PGE2, and BDNF; and downregulated glial fibrillary acidic protein in the hippocampus of PILO-treated rats. In addition, MOE enhanced GSH and antioxidant enzymes, upregulated Nrf2 and HO-1 mRNA abundance, and increased the nuclear translocation of Nrf2 in the hippocampus of epileptic rats. Na⁺/K⁺-ATPase activity and GABA were increased, and glutamate and acetylcholine were decreased in the hippocampus of epileptic rats treated with MOE. In conclusion, MOE attenuated neuronal loss, oxidative stress, and inflammation; activated Nrf2/HO-1 signaling; and modulated neurotransmitters, GFAP, and Na⁺/K⁺-ATPase in the hippocampus of epileptic rats. These findings suggest that M. officinalis can mitigate epileptogenesis, pending further studies to explore the exact underlying mechanisms.

Potential antiviral effects of some native Iranian medicinal plants extracts and fractions against influenza A virus

Background

Influenza A virus (IAV) infection is a continual threat to the health of animals and humans globally. Consumption of the conventional drugs has shown several side effects and drug resistance. This study was aimed to screen some Iranian medicinal plants extracts and their fractions against influenza A virus.

Methods

Glycyrrhiza glabra (rhizome), Myrtus  commonis (leaves), Melissa officinalis (leaves), Hypericum perforatum (aerial parts), Tilia platyphyllos (flower), Salix alba (bark), and Camellia sinensis (green and fermented leaves) were extracted with 80% methanol and fractionated with chloroform and methanol, respectively. The cytotoxicity of the compounds were determined by MTT colorimetric assay on MDCK cells. The effective concentrations (EC₅₀) of the compounds were calculated from the MTT results compared to the negative control with no significant effects on cell viability. The effects of EC₅₀ of the compounds on viral surface glycoproteins and viral titer were tested by HI and HA virological assays, respectively and compared with oseltamivir and amantadine. Preliminary phytochemical analysis were done for promising anti-IAV extracts and fractions.

Results

The most effective samples against IAV titer (P ≤ 0.05) were crude extracts of G. glabra, M. officinalis and S. alba; methanol fractions of M. communis and M. officinalis; and chloroform fractions of M. communis and C. sinensis (fermented) mostly in co- and pre-penetration combined treatments. The potential extracts and fractions were rich in flavonoids, tannins, steroids and triterpenoids.

Conclusion

The outcomes confirmed a scientific basis for anti-influenza A virus capacity of the extracts and fractions from the selected plants for the first time, and correlated their effects with their phytochemical constituents. It is worth focusing on elucidating pure compounds and identifying their mechanism(s) of action.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03423-x.

The herbal extract ALS-L1023 from Melissa officinalis reduces weight gain, elevated glucose levels and β-cell loss in Otsuka Long-Evans Tokushima fatty rats

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L. (Labiatae; lemon balm) is a traditional medicinal plant with hypoglycemic and hypolipidemic effects; however, how it imparts its beneficial effects remains unclear. We thus hypothesized that the herbal extract ALS-L1023, isolated from Melissa officinalis, inhibits obesity and diabetes, and tested our hypothesis using Otsuka Long-Evans Tokushima fatty (OLETF) rats, which are an established animal model of type 2 diabetes.

MATERIALS AND METHODS

In this study, 28-week-old OLETF rats were fed a high-fat diet for 4 weeks to induce a marked impairment of the insulin response and were treated with or without ALS-L1023. Subsequently, the variables and determinants of glucose metabolism and pancreatic function were assessed via blood analysis, histology, immunohistochemistry, and real-time polymerase chain reaction.

RESULTS

The administration of ALS-L1023 resulted in a weight reduction without changes in food intake. It also markedly inhibited hyperglycemia and hypoinsulinemia, and restored β-cell mass that was severely impaired in OLETF rats. There was a decrease in lipid accumulation in the liver and skeletal muscle of the obese rats after treatment with ALS-L1023. Concomitantly, there was an increase in the expression levels of fatty acid-oxidizing enzymes (AMPKα2, ACOX, MCAD, and VLCAD) in the liver and skeletal muscle after ALS-L1023 treatment. Furthermore, ALS-L1023 attenuated the pancreatic inflammation including the infiltration of CD68-positive macrophages and mast cells, in addition to attenuating the expression of inflammatory factors (IL-6 and CD68).

CONCLUSIONS

These results suggest that treatment with ALS-L1023 may reduce weight gain, elevated glucose levels, and β-cell loss, by changing the expression of fatty acid-oxidizing enzymes in the liver and skeletal muscle, including inflammatory factors in the pancreas. These findings indicate that ALS-L1023 may be an effective therapeutic strategy to treat human obesity and type 2 diabetes.

Use of Plant-Derived Natural Products in Sleep Disturbances

Sleep disorders have a high prevalence both in the general population and especially in specific populations such older adults and oncologic patients. Impacting on quality of life, they often translate in drug prescription, with consequent increased risk of drug-drug interactions and adverse drug reactions. In the last years several products derived from plants have been developed with the aim of treating insomnia with lower risk of side effects. Despite several studies have been performed with this aim, the available evidence is inconclusive, and reviews summarizing the most recent evidences on the effectiveness of plant-derived products in treating insomnia are lacking.This narrative review aims at summarizing the evidences of the mechanism of action, effectiveness and safety of the most commonly used plant-derived products for the treatment of sleep disorders (Valerian, Lemon balm, Passionflower, Chamomile, Hops, and Jujube).

Addition of Valerian and Lemon Balm Extract to Quetiapine Reduces Agitation in Critically Ill Patients with Delirium: A Pilot Randomized Clinical Trial

Background

This study was pointed to evaluate the efficacy and safety of valerian and lemon balm additional to the quetiapine in critically ill patients with delirium and agitation.

Methods

We conducted a randomized, double-blind, placebo-controlled study. Fifty-three adult intensive care unit (ICU) patients (according to ICU Confusion Assessment Method scores) who were treated for delirium received quetiapine and Neurogol syrup (a combination of valerian and lemon balm) or placebo 5 mL every 12 hours for five consecutive days. Improvement in agitation according to the Richmond Sedation and Restlessness Scale was considered the main outcome.

Results

The trial was completed for 53 patients (27 in the treatment group and 26 in the placebo group). The baseline characteristics between the groups were similar. In the treatment group, the number of agitated patients was significantly reduced and the difference was statistically significant (p = 0.000). Compared with the placebo group, the length of ICU stay in the treatment group was significantly reduced (p = 0.001). The Glasgow Coma Scale improved significantly at the end of day 5 (p = 0.04). There was no statistical difference in the improvement of delirium between the study groups (p = 0.14). Neurogol syrup was well tolerated.

Conclusion

The addition of Neurogol to quetiapine (a combination of valerian and lemon balm) can reduce agitation and shorten the length of stay in the ICU without adverse effects. Clearly, more research is still needed to investigate the role of herbal medicines in ICUs and their efficacy and safety.

How to cite this article

Alikiaie B, Shahmoradi E, Yekdaneh A, Mousavi S. Addition of Valerian and Lemon Balm Extract to Quetiapine Reduces Agitation in Critically Ill Patients with Delirium: A Pilot Randomized Clinical Trial. Indian J Crit Care Med 2021;25(7):785–790.

Target specific post-harvest treatment by gamma radiation for the microbial safety of dried Melissa officinalis and Aloysia citrodora

This study aimed to assess a specific gamma radiation dose to be applied as a post-harvest process to guarantee the microbial safety of two medicinal plants, Melissa officinalis and Aloysia citrodora. Dried plants treated with gamma radiation indicated that a dose of 5 kGy could be applied as a post-harvest treatment process of M. officinalis and A. citrodora, assuring the microbial safety of dried medicinal plants and lowering the potentiality of deleterious effects on plants' quality attributes. This will enhance the safety and quality of the dried plants to be used as raw materials in industrial applications.

Eliciting effect of foliar application of chitosan lactate on the phytochemical properties of Ocimum basilicum L. and Melissa officinalis L

An increase in the content of secondary metabolites in herbal plants is desirable due to their therapeutic and nutraceutical properties. Therefore, the effects of foliar spray of 100 mg/L or 500 mg/L of chitosan lactate (ChL) on the accumulation of selected phenolics and physiological parameters of basil and lemon balm were investigated. In basil, the concentration of rosmarinic acid (RA) increased after application of 100 mg/L of ChL. In turn, in lemon balm both ChL concentrations increased the accumulation of RA and anthocyanins, while the level of total phenolic compounds (TPC) was elevated only at the dose of 100 mg/L of ChL. Elicitation of basil with 500 mg/L of ChL increased the shoot biomass. Therefore, such an elicitor as ChL can enhance the accumulation of valuable phytochemicals in Lamiaceae species. This simple and non-laborious method can be used for elicitation of herbal plants in production of functional food.

LED light mediates phenolic accumulation and enhances antioxidant activity in Melissa officinalis L. under drought stress condition

The popularity of lemon balm in conventional medicine is suggested by the existence of two groups of compounds, namely essential oil and phenylpropanoids pathway derivatives. One of the promising approaches to improve tolerance to drought stress induced oxidative damage in seedlings grown in greenhouses and plant growth chambers is replacing the traditional and high-cost light technologies by recently developed light emitting diodes (LED). In this experiment, we analyzed the role of various LED lights including red (R), blue (B), red (70%) + blue (30%) (RB), and white (W) as well as normal greenhouse light (as control) to stimulate defense mechanisms against drought stress in two genotypes of Melissa officinalis L. The present study demonstrates that pre-treatment with LEDs with high-intensity output for 4 weeks alleviated harmful effects of drought stress in the two genotypes. Under drought stress, RB LED pre-treated plantlets of the two genotypes exhibited the highest relative growth index of shoot and root and total phenolic and anthocyanin content compared to those irradiated with other LEDs and greenhouse lights. The highest amount of malondialdehyde level was detected in R LED exposed plants. In response to drought, LED-exposed plants especially RB light-irradiated plants of the two genotypes maintained significantly higher antioxidant and phenylalanine ammonia-lyase (PAL) enzyme activities and higher expression level of the PAL1 and 4CL-1 genes compared to those irradiated with greenhouse light. We concluded that RB LED light provides a better growth condition and resistance to drought stress for the two genotypes of lemon balm by the highest antioxidant activity and the least amount of damage to the cell membranes. Our data suggest that LED light pre-treatments as moderate stress activate antioxidant systems, enhance the scavenging of ROS and induce drought stress tolerance in the two genotypes of lemon balm plants.

The herbal extract ALS-L1023 from Melissa officinalis alleviates visceral obesity and insulin resistance in obese female C57BL/6J mice

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L. (Labiatae; lemon balm) has traditionally been used as a medicinal herb to treat stress, anxiety, and insomnia. Current reports suggest that not only chronic stress stimulates angiogenesis, but angiogenesis also regulates adipogenesis and obesity. Because the herbal extract ALS-L1023 from Melissa officinalis inhibits angiogenesis, we hypothesized that ALS-L1023 could suppress visceral obesity and insulin resistance in obese female C57BL/6J mice, a mouse model of obese premenopausal women.

MATERIALS AND METHODS

The mice were grouped and fed for 16 weeks as follows: 1) low-fat diet (LFD), 2) high-fat diet (HFD), or 3) HFD supplemented with 0.4 or 0.8% ALS-L1023. Variables and determinants of visceral obesity, insulin resistance, and pancreatic dysfunction were then assessed via blood analysis, histology, immunohistochemistry, and real-time polymerase chain reaction.

RESULTS

ALS-L1023 decreased weight gain, visceral adipocyte size, and serum lipid levels in HFD-fed obese mice. ALS-L1023 also normalized hyperglycemia and hyperinsulinemia and concomitantly reduced blood glucose levels during oral glucose tolerance tests. The pancreatic islet size and insulin-positive β-cell area were significantly reduced in ALS-L1023-treated mice compared with untreated obese controls, reaching a level similar to that of LFD-fed lean mice. ALS-L1023 suppressed pancreatic lipid accumulation, infiltration of inflammatory cells, and collagen levels. ALS-L1023 treatment altered the pancreatic expression of genes involved in steatosis, inflammation, and fibrosis.

CONCLUSIONS

Our findings indicate that the herbal extract ALS-L1023 from Melissa officinalis not only inhibits visceral obesity, but also attenuates the increased fasting blood glucose, impaired glucose tolerance, and pancreatic dysfunction seen in female obese mice. These results suggest that ALS-L1023 may be effective in the prevention of visceral obesity and insulin resistance in obese premenopausal women.

Effect of lemon balm (Melissa officinalis) extract on growth performance, digestive and antioxidant enzyme activities, and immune responses in rainbow trout (Oncorhynchus mykiss)

This study was conducted to determine the effects of dietary supplementation of lemon balm (Melissa officinalis) aqueous methanolic extract on growth performance, blood parameters, digestive and antioxidant enzyme activities, and non-specific immune responses in rainbow trout (Oncorhynchus mykiss). Fish with an average weight of 23.03 ± 0.07 g were fed a diet supplemented with an aqueous methanolic extract of lemon balm at a dose of 0 (control), 0.1 (LB0.1), 0.5 (LB0.5), and 1 g kg^-1 (LB1) for 75 days. The final weight, weight gain, and specific growth rate were observed to be significantly increased in LB0.5 and LB1 groups compared with that of the control. No differences were observed in feed conversion ratio values. WBC increased at the 45th day of the study in LB0.1 group. No differences were determined in RBC (P > 0.05). At the end of the study, lipase increased significantly in all experimental groups compared with the control. Pepsin was also elevated in LB0.5 and LB1 groups compared with the control. Increased trypsin was determined in LB1 group (P < 0.05). SOD activity increased at the end of the study in LB1 group (P < 0.05). CAT values had no differences compared with control. GR activity increased in all experimental groups compared with control. GPx improved in LB0.5 and LB1 groups significantly (P < 0.05). Lipid peroxidation was decreased in LB1 group compared with that of control, but this decrease was not significant (P < 0.05). Oxidative radical production and lysozyme activity significantly increased in LB1 group (P < 0.05). The highest MPO was determined in control group (P < 0.05). Current results suggest that lemon balm extract stimulates growth promoting antioxidant and immune responses in rainbow trout.

Influence of medicinal and aromatic plants into risk assessment of a new bioactive packaging based on polylactic acid (PLA)

A new biodegradable antioxidant active packaging for food applications based on antioxidants from medicinal and aromatic plants incorporated into a polylactic acid matrix was designed and developed. Melt blending processing technique was applied to prepare polylactic acid films loaded by sage and lemon balm leaves. Antioxidant properties of developed active films were investigated using the following methods: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl and a home-made generator of hydroxyl radicals. In addition, reducing power and total phenolic content of polylactic acid films were checked. The results of antioxidant capacity showed that percentage of hydroxylation for active film with lemon balm and sage was 55.5% ± 0.1% and 67.4% ± 0.3%, respectively. The reducing power of active films increased 8 times in comparison to the blank samples. Moreover, extensive investigation of influence of sage and lemon balm leaves on material safety and type of migrants was performed using migration assays. The composition of both non-volatile and volatile compounds of different active packaging films was compared with neat polylactic acid film. Three different food simulants such as 95% (v/v) ethanol, 10% (v/v) ethanol and 3% (w/v) acetic acid were checked. It was shown that the addition of sage and lemon balm leaves into a polylactic acid structure decreased the migration of both linear and cyclic polylactic acid oligomers, currently not legislated by European Union. Besides, total absence or decrease of migration of volatile compounds were observed when using the active films. Both thermal and mechanical properties of films were also evaluated.

The Protective Effect of Melissa officinalis L. in Visceral Hypersensitivity in Rat Using 2 Models of Acid-induced Colitis and Stress-induced Irritable Bowel Syndrome: A Possible Role of Nitric Oxide Pathway

Background/Aims

The aim of present study is to estimate the effects of Melissa officinalis L. (MO) on visceral hypersensitivity (VH), defecation pattern and biochemical factors in 2 experimental models of irritable bowel syndrome (IBS) and the possible role of nitric oxide.

Methods

Two individual models of IBS were induced in male Wistar-albino rats. In the acetic acid model, the animals were exposed to rectal distension and abdominal withdrawal reflex, and the defecation patterns were determined. In the restraint stress model, the levels of TNF-α, myeloperoxidase, lipid peroxidation, and antioxidant powers were determined in the (removed) colon. Rats had been treated with MO, L-NG-nitroarginine methyl ester (L-NAME), aminoguanidine (AG), MO + AG, or MO + L-NAME in the mentioned experimental models.

Results

Hypersensitive response to rectal distension and more stool defecation in control rats have been observed in comparison to shams. MO-300 significantly reduced VH and defecation frequency in comparison to controls. VH and defecation pattern did not show significant change in AG + MO and L-NAME + MO groups compared to controls. Also, significant reduction in TNF-α, myeloperoxidase, thiobarbituric acid reactive substances (TBARS), and an increase in antioxidant power in MO-300 group was recorded compared to controls. AG + MO and L-NAME + MO groups showed a reverse pattern compared to MO-300 group.

Conclusions

MO can ameliorate IBS by modulating VH and defecation patterns. Antioxidant and anti-inflammatory properties along with its effect on the nitrergic pathway seem to play important roles in its pharmacological activity.

Suitability of lemon balm (Melissa officinalis L.) extract rich in rosmarinic acid as a potential enhancer of functional properties in cupcakes

Melissa officinalis (lemon balm) and its extracts have been frequently reported as possessing bioactive properties, offering the potential for use in development/enrichment of food products with additional functional capabilities, providing health benefits to consumers. The antioxidant, antibacterial and antifungal activity of lemon balm extract, as well as its potential hepatotoxicity were thoroughly evaluated. The extracts were then incorporated into cupcakes and their preserving effect, chemical composition, colour parameters and antioxidant activity were compared with those provided by potassium sorbate. In general, the variables with the largest differences among different storage times were energy level, sucrose, glucose, palmitic acid (C6:0) and oleic acid (C18:1n9). On the other hand, L∗ (top), a∗ (top), b∗ (top), pH, capric acid (C10:0) and lauric acid (C12:0) showed the greatest variation according to cupcake formulation. The results observed indicate that the lemon balm extract rich in rosmarinic acid can provide advantageous functional properties to bakery products.

Effect of Melissa officinalis (Lemon balm) on Sexual Dysfunction in Women: A Double- blind, Randomized, Placebo-controlled Study

Hypoactive sexual desire disorder (HSDD) is the most prevalent female sexual dysfunction (FSD) and its bio-psychosocial multifactorial etiology justifies its multifaceted treatment. In Persian Medicine (PM), the weakness of the main organs (heart, brain and liver) is one of the important causes of lack of sexual desire; hence, their strengthening is a priority during treatment. Melissa officinalis is one of the medicinal plants with tonic characteristics for the main organs in PM and was used for treatment in this study. The aim of the present study was to evaluate the efficacy and safety of M. officinalis in the improvement of HSDD in women. Eighty nine (89) eligible women suffering from decreased sexual desire were randomly assigned to groups. The participants received medication (500 mg of aqueous extract of M. officinalis) or placebo 2 times a day for 4 weeks. Changes in scores of desire, arousal, lubrication, orgasm, satisfaction and pain were evaluated at the end of 4 weeks of treatment using the Female Sexual Function Index (FSFI) questionnaire in the two groups. Forty three participants completed the study. The increase in desire (P < 0.001), arousal (P < 0.001), lubrication (P < 0.005), orgasm (P < 0.001), satisfaction (P < 0.001), pain (P < 0.002) and FSFI total score (P < 0.001) in the M. officinalis group was significantly more than that of the placebo group. The willingness to continue treatment was significantly higher in the M. officinalis as compared to the placebo group (P < 0.001). M. officinalis may be a safe and effective herbal medicine for the improvement of HSDD in women.

A Comparative Study on Essential Oil Intraspecific and Seasonal Variations: Melissa romana Mill. and Melissa officinalis L. from Sardinia

Two species of Melissa are currently present in Sardinia: Melissa officinalis L. and Melissa romana Mill. Our research can only count on a few supported evidences (as reported in Flora Italiana and Moris) and some notes on new stations in Sardinia that give us some information about morphology, distribution, bioecological, and ethnobotanical characteristics of both species. In this paper, we present the results of the research about morphological aspects of M. romana vs. M. officinalis, and their essential oils in different stations at different phenological periods. Moreover, we compared the essential oil of M. romana with the one obtained from M. officinalis growing in the few naturalized stations still present in Sardinia. The most evident morphological differences between the two entities are the long-stalked capitate glandular trichomes, shorts and inclined capitate trichomes, and peltate hairs. The chemical composition of essential oil presents several significant differences between the species. In fact, oils show that in none of the phenological stages, M. romana recalls in its composition M. officinalis. Major distinctions are also evident between dry and fresh plants, and among essential oils distilled in different seasons.

Melissa officinalis L. - A review of its traditional uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L. is a medicinal plant that has long been used in different ethno-medical systems especially in the European Traditional Medicine and the Iranian Traditional Medicine for the treatment of several diseases. It is also widely used as a vegetable and to add flavor to dishes

AIM OF THE REVIEW

This review aimed to provide a summary on the botanical characterization, traditional uses, phytochemistry, pharmacological activities, pharmacokinetics and toxicity of M. officinalis, and discusses research gaps and future opportunities for investigations on this plant.

MATERIALS AND METHODS

We extensively reviewed major unpublished old texts, and published and electronic literature on traditional medicines of different regions of the world to find traditional uses of M. officinalis. Electronic databases including Web of Science, PubMed, ScienceDirect, Google Scholar and Scopus were searched to find articles (published between 1956 and 2015) on pharmacology and phytochemistry of M. officinalis.

RESULTS

Traditional uses of M. officinalis have been recorded mostly in European countries, Mediterranean region and Middle East countries. Phytochemical investigations revealed that this plant contains volatile compounds, triterpenoids, phenolic acids and flavonoids. Crude extracts and pure compounds isolated from M. officinalis exhibited numerous pharmacological effects, from which only anxiolytic, antiviral and antispasmodic activities of this plant as well as its effects on mood, cognition and memory have been shown in clinical trials. AChE inhibitory activity, stimulation of the acetylcholine and GABAA receptors, as well as inhibition of matrix metallo proteinase-2 are the main mechanisms proposed for the widely discussed neurological effects of this plant.

CONCLUSIONS

Modern pharmacological studies have now validated many traditional uses of M. officinalis. The data reviewed here revealed that M. officinalis is a potential source for the treatment of a wide range of diseases especially anxiety and some other CNS disorders, though confirmatory trials are warranted to substantiate these effects in the clinical setting. Data regarding many aspects of this plant such as mechanisms of actions, pharmacokinetics, adverse effects of the extracts, potential interactions with standard-of-care medications and active compounds is still limited which call for additional studies particularly in humans.

Colic management: an interview with Professors Staiano and Miele

Annamaria Staiano and Erasmo Miele speak to Francesca Lake, Managing Editor: Following the presentation of the results from an Italian trial on the treatment of infantile colic through the combination of herbal agents and probiotics, Annamaria Staiano (Professor of Paediatrics) and Erasmo Miele (Assistant Professor of Paediatrics; both Naples University, Italy) discuss childhood gastrointestinal disorders. With an introduction to the topic written by Staiano, Miele proceeds to further discuss the topic.

Extracts from peppermint leaves, lemon balm leaves and in particular angelica roots mimic the pro-secretory action of the herbal preparation STW 5 in the human intestine

AIM

The herbal preparation STW 5 contains fresh plant extracts from bitter candytuft whole plant, extracts from greater celandine herb, angelica root, lemon balm leaves, peppermint leaves, caraway fruit, liquorice root, chamomile flower and milk thistle fruit. We recently reported that STW 5 increased intestinal chloride secretion and proposed that this action may be involved in its clinical efficacy in the treatment of irritable bowel syndrome. The aim of this study was to identify the extracts responsible for the secretory action in order to provide the basis to develop novel target oriented herbal combinations.

METHODS

We used the Ussing chamber voltage clamp technique to study the effects of individual extracts of STW 5 on short circuit current (Isc, reflecting electrogenic ion transport across epithelial cells) in mucosal/submucosal preparations of human small or large intestinal specimens and the human epithelial cell line T84.

RESULTS

STW 5 at concentrations of 512 µg/ml and 5120 µg/ml evoked an increase in Isc. The increase at the lower concentration was due to pro-secretory effects of angelica which were nerve mediated. The increase at the higher concentration was additionally mimicked by peppermint and lemon balm. The remaining extracts did not influence ISC in the large intestine. The results were similar in T84 cells except that angelica had no effect while chamomile induced secretion. These pro-secretory effects were reduced by adenylate cyclase inhibitor MDL-12330A, cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor CFTRinh-172 and calcium activated chloride channels blocker 4-acetamido-4-isothiocyanatostilbene-2,2-disulphonic acid (SITS). Liquorice decreased ISC only in small intestine which was reversed by the epithelial sodium channel blocker amiloride.

CONCLUSIONS

Results suggested that the pro-secretory action of STW 5 is mainly due to angelica with lesser contribution of peppermint and lemon balm. Their effects involve activation of cAMP- and Ca(++)-activated Cl(-) channels. We suggest that peppermint, lemon balm and in particular angelica may be the basis to develop novel herbal preparations to specifically treat secretory disorder based on impaired epithelial secretion, such as constipation.

Heart palpitation relief with Melissa officinalis leaf extract: double blind, randomized, placebo controlled trial of efficacy and safety

ETHNOPHARMACOLOGICAL RELEVANCE

In Traditional Iranian Medicine (TIM), Melissa officinalis L. is commonly regarded as an effective therapy for heart palpitations.

OBJECTIVE

Heart palpitation is a common complaint that is often benign and associated with a marked distress that makes the condition difficult to treat. Herbal medicines provide an alternative to conventional drugs for treating various kinds of diseases. This study was done as a double blind randomized placebo-controlled clinical trial to evaluate the efficacy and safety of the dried extract of M. officinalis on adults suffering from benign palpitations.

MATERIALS AND METHODS

Eligible volunteers were randomly assigned as outpatients to a 14 day treatment with 500 mg twice a day of lyophilized aqueous extract of M. officinalis leaves (or placebo). Participants in the tests, physicians and researchers were blind to group assignments. Both primary and secondary outcomes were patient-reported. Primary outcomes were obtained from two measures: mean frequency of palpitation episodes per week, derived from patients׳ diaries, and mean intensity of palpitation estimated through Visual Analogue Scale (VAS) in a self-report questionnaire. Psychiatric symptoms (somatization, anxiety and insomnia, social dysfunction and severe depression) were evaluated as secondary outcomes by General Health Questionnaire-28 (GHQ-28), before and after intervention.

RESULTS

Fifty-five volunteers out of 71 recruited study subjects completed the trial. Results showed that 14-day of treatment with lyophilized aqueous extract of M. officinalis leaves reduced frequency of palpitation episodes and significantly reduced the number of anxious patients in comparison to the placebo (P=0.0001, P=0.004 resp.). Also, M. officinalis extract showed no indication of any serious side effects.

CONCLUSION

Lyophilized aqueous extract of M. officinalis leaves may be a proper and safe herbal drug for the treatment of benign palpitations.

How do background ozone concentrations affect the biosynthesis of rosmarinic acid in Melissa officinalis?

Lemon balm (Melissa officinalis; Lamiaceae) plants were exposed to background ozone (O3) dosages (80ppb for 5h), because high background levels of O3 are considered to be as harmful as episodic O3 peaks. Immediately at the end of fumigation the plants appeared visually symptomless, but necrotic lesions were observed later. The biosynthesis of rosmarinic acid (RA) comprises eight enzymes, among them phenylalanine ammonia-lyase (PAL), 4-coumarate:coenzyme A ligase (4CL), tyrosine aminotransferase (TAT) and rosmarinic acid synthase (RAS). The transcript levels of these genes have been investigated by quantitative RT-PCR. There was a quick up-regulation of all genes at 3h of O3 exposure, but at 24h from beginning of exposure (FBE) only RAS and PAL were up-regulated. The specific activity of RAS was closely correlated with a decrease of RA concentration in lemon balm leaves. The specific activity of PAL increased at 12h FBE to 163% in comparison to control levels. This work provides insight into the effect of O3 stress on the formation of the main phenolic ingredient of the pharmaceutically important plant M. officinalis.

How sensitive is Melissa officinalis to realistic ozone concentrations?

Lemon balm (Melissa officinalis, L.; Lamiaceae) was exposed to realistic ozone (O3) dosages (80 ppb for 5 h), because high background levels of O3 are considered to be as harmful as episodic O3 regimes. Temporal alterations of different ecophysiological, biochemical and structural parameters were investigated in order to test if this species can be considered as an O3-bioindicator regarding changes in background concentrations. At the end of ozone exposure, the plants did not exhibit any visible foliar symptoms, as only at microscopic level a small number of dead cells were found. Photosynthetic processes, however, were significantly affected. During and after the treatment, ozone induced a reduction in CO2 fixation capacity (up to 52% after 12 h from the beginning of the treatment) due to mesophyllic limitations. Intercellular CO2 concentration significantly increased in comparison to controls (+90% at the end of the post-fumigation period). Furthermore impairment of carboxylation efficiency (-71% at the end of the post-fumigation period compared to controls in filtered air) and membrane damage in terms of integrity (as demonstrated by a significant rise in solute leakage) were observed. A regulatory adjustment of photosynthetic processes was highlighted during the post-fumigation period by the higher values of qNP and (1-q(P)) and therefore suggests a tendency to reduce the light energy used in photochemistry at the expense of the capacity to dissipate the excess as excitation energy. In addition, the chlorophyll a/b ratio and the de-epoxidation index increased, showing a rearrangement of the pigment composition of the photosynthetic apparatus and a marked activation of photoprotective mechanisms.