Sleep-inducing effect of lettuce (Lactuca sativa) varieties on pentobarbital-induced sleep

Heukharang (Lactuca sativa L.) extracts enhanced the sleep behavior of mice: potential involvement of adenosine A1 and A2A receptors

A significant proportion of the world's population suffers from insomnia, a disorder characterized by complications in initiating and maintaining sleep. Many medications used to treat insomnia target the γ-aminobutyric acid (GABA) neurotransmitter system. However, these substances, such as benzodiazepines, induce significant adverse consequences, including dependence and memory impairment, after prolonged use. Thus, current studies are aimed at developing therapeutic hypnotics derived from natural sources that may cause less severe side effects. Heukharang is a variety of lettuce from Korea that was discovered to contain sleep-promoting compounds. Therefore, we investigated the potential effects of sub-chronic administration of Heukharang extract (FSD-LS) on sleep behavior (pentobarbital-induced sleeping test), brain wave activity and sleep architecture (electroencephalography), and physiological behavior (open-field test and rota-rod) in mice, along with radioligand binding assays (GABAA, adenosine A1 and A2A receptors). We found that FSD-LS prolonged the total sleep duration and reduced the onset time of sleep, and enhanced delta wave power and non-rapid eye movement (NREM) sleep duration, all indicating persistent sleep-enhancing effects. FSD-LS lacked adverse effects on the spontaneous locomotor activity and motor coordination of mice, unlike diazepam. Pharmacological blocking using caffeine and bicuculline supported the possible involvement of adenosine receptors in the sleep-promoting effects of FSD-LS, with partial contribution from GABA receptor activity. Overall, our study recommends FSD-LS as a potential source for the development of sleep-aiding therapeutics.

Lactuca sativa L. Extract Enhances Sleep Duration Through Upregulation of Adenosine A1 Receptor and GABAA Receptors Subunits in Pentobarbital-Injected Mice

We investigated the effects of Lactuca sativa L. extracts (Lactuc) on pentobarbital-induced sleep in mice to elucidate the mechanisms underlying its impact on sleep quality. Mice were randomly assigned to five groups: control, positive control (diazepam 2 mg/kg b.w.), and three groups orally administered with Lactuc (50, 100, and 200 mg/kg b.w.). After 2 weeks of oral administration and intraperitoneal injections, the mice were killed. We found that the Lactuc-administered groups had significantly reduced sleep latency and increased sleep duration compared with the control group. Furthermore, the oral administration of Lactuc induced a significant increase in mRNA expression and protein expression of adenosine A1 receptor in the brains compared with the expressions in the control group. In addition, the Lactuc-administered groups exhibited significantly higher levels of mRNA expressions of GABAA receptors subunits α2, β2, γ1, and, γ2 in the brain tissue. Therefore, we suggest that Lactuc could be used to develop natural products that effectively improve sleep quality and duration.

Therapeutic potential of hypnotic herbal medicines: A comprehensive review

Insomnia affects millions of people worldwide, prompting considerable interest in herbal remedies for its treatment. This review aims to assess the therapeutic potential of such remedies for insomnia by analyzing current scientific evidence. The analysis identified several herbs, including Rosmarinus officinalis, Crocus sativus, Rosa damascena, Curcuma longa, Valeriana officinalis, Lactuca sativa, Portulaca oleracea, Citrus aurantium, Lippia citriodora, and Melissa officinalis, which show promise in improving overall sleep time, reducing sleep latency, and enhancing sleep quality. These plants act on the central nervous system, particularly the serotonergic and gamma-aminobutyric acid (GABA)ergic systems, promoting sedation and relaxation. However, further research is necessary to fully understand their mechanisms of action, optimal dosages, and treatment protocols. Combining herbal medicines with conventional treatments may offer an effective natural alternative for those seeking medication. Nevertheless, individuals should consult their healthcare provider before using herbal remedies for insomnia. While this review provides evidence supporting their use, additional high-quality studies are needed to firmly establish their clinical efficacy.

Effect of Selenium and Garlic Extract Treatments of Seed-Addressed Lettuce Plants on Biofortification Level, Seed Productivity and Mature Plant Yield and Quality

The enhancement of the plant seed yield and quality represents the basis of the successful productivity of the deriving crop. The effect of single and combined foliar treatments of lettuce plants with sodium selenate and garlic bulb extract on seed yield and quality and on mature plant biochemical characteristics was investigated using four lettuce cultivars (Bouquet, Picnic, Moskovsky parnikovy and Cavalier). The seed production of plants treated with Se increased by 20-41%, compared to the untreated control plants, while the augmentation was as much as 10-23% and 17-27% under garlic extract and the joint application of Se and garlic, respectively. Garlic extract stimulated the accumulation of Se in lettuce seeds, which rose by 1.21-1.29 times compared to the Se-treated plants. The proline levels in lettuce seeds exceeded the corresponding values recorded in the control ones by 1.32-1.64 times in the case of the Se supply, 1.10-1.47 times upon garlic extract application and 1.09-1.31 times under the combined Se/garlic treatment. All the treatments given to lettuce plants increased the leaf weight by 1.10-1.30 times, compared to the untreated control. The seed Se levels positively correlated with the leaf weight (r = 0.621; p < 0.005), chlorophyll (r = 0.672, p < 0.002) and total antioxidant activity (AOA; r = 0.730, p < 0.001) of plants grown from these seeds. Positive correlations were also recorded between the seed proline content and lettuce plant leaf weight, chlorophyll and AOA (r = 0.868, 0.811 and 0.815, respectively, at p < 0.001). Lettuce yield was positively correlated with the leaf AOA, chlorophyll and ascorbic acid content (r = 0.942, 0.921 and 0.665, respectively, at p < 0.001). The results indicate high prospects of Na2SeO4 and garlic extract application to seed-addressed lettuce plants, to improve seed productivity and quality, as well as lettuce yield and quality.

Edible Herbal Medicines as an Alternative to Common Medication for Sleep Disorders: A Review Article

Insomnia is repeated difficulty in falling asleep, maintaining sleep, or experiencing lowquality sleep, resulting in some form of daytime disturbance. Sleeping disorders cause daytime fatigue, mental confusion, and over-sensitivity due to insufficient recovery from a sound sleep. There are some drugs, such as benzodiazepines and anti-histaminic agents, which help to sleep induction and insomnia cure. However, the prolonged administration is unsuitable because of tolerance and dependence. Therefore, the researchers attempt to find new medicines with lesser adverse effects. Natural products have always been good sources for developing new therapeutics for managing diseases such as cancer, cardiovascular disease, diabetes, insomnia, and liver and renal problems. Ample research has justified the acceptable reason and relevance of the use of these herbs in the treatment of insomnia. It is worth noting that in this study, we looked into various Persian herbs in a clinical trial and in vivo to treat insomnia, such as Artemisia annua, Salvia reuterana, Viola tricolor, Passiflora incarnata, lettuce, and Capparis spinose. According to research, herb extracts and fractions, particularly n-butanol fractions with non-polar agents, impact the benzodiazepine receptors and have hypnotic properties. Also, alkaloids, glycosides, flavonoids, saponins, and tannins in practically every plant are mentioned making them the popular natural compounds to help with sleep disorders and promote calmness.

Aralia continentalis Root Enhances Non-Rapid Eye Movement Sleep by Activating GABAA Receptors

Aralia continentalis exhibits various biological activities; however, their sleep-promoting effects have not been previously reported. In this study, we evaluated the hypnotic effects and sleep-wake profiles of A. continentalis root (KS-126) using a pentobarbital-induced sleep-acceleration test and polysomnographic recordings. Additionally, we investigated the molecular mechanism of KS-126 through patch-clamp electrophysiology. Our polysomnographic recordings revealed that KS-126 not only accelerated the onset of non-rapid eye movement sleep (NREMS) but also extends its duration. Considering the temporal dynamics of the sleep-wake stages, during the initial and subsequent periods KS-126 extended NREMS duration and decreased wakefulness, thereby enhancing sleep-promoting effects. Furthermore, the assessment of sleep quality via analysis of electroencephalogram power density indicated that KS-126 did not significantly alter sleep intensity. Finally, we found that KS-126 enhanced GABAA receptor-mediated synaptic responses in primary hippocampal neurons, leading to an increase in the percentage of the GABA current. This effect was not affected by the selective benzodiazepine receptor antagonist flumazenil, but was entirely inhibited by the GABAA receptor antagonist bicuculline. In conclusion, KS-126 extends the duration of NREMS without altering its intensity by prolonging GABAergic synaptic transmission, which modulates GABAA receptor function.

Heukharang lettuce (Lactuca sativa L.) leaf extract displays sleep-promoting effects through GABAA receptor

ETHNOPHARMACOLOGICAL RELEVANCE

Although lettuce is traditionally known to have hypnotic and sedative effects, to date, only a few studies have documented its sleep-promoting effects and elucidated the related mechanisms.

AIM OF THE STUDY

We aimed to investigate the sleep-promoting activity of Heukharang lettuce leaf extract (HLE) with increased lactucin content, known as a sleep-promoting substance in lettuce, in animal models.

MATERIALS AND METHODS

To evaluate the effect of HLE on sleep behavior, analysis of electroencephalogram (EEG), gene expression of brain receptors, and activation mechanisms using antagonists were investigated in rodent models.

RESULTS

High-performance liquid chromatography analysis showed that HLE contained lactucin (0.78 mg/g of extract) and quercetin-3-glucuronide (1.3 mg/g of extract). In the pentobarbital-induced sleep model, the group administered 150 mg/kg of HLE showed a 47.3% increase in sleep duration time as compared to the normal group (NOR). The EEG analysis showed that the HLE significantly increased non-rapid eye movement (NREM), where delta waves were improved by 59.5% when compared to the NOR, resulting in increased sleep time. In the caffeine-induced arousal model, HLE significantly decreased the awake time increased by caffeine administration (35.5%) and showed a similar level to NOR. In addition, HLE increased the gene and protein expression of gamma-aminobutyric acid receptor type A (GABAA), GABA type B, and 5-hydroxytryptamine (serotonin) receptor 1A. In particular, in comparison to the NOR, the group administered 150 mg/kg HLE showed an increase in expression levels of GABAA and protein by 2.3 and 2.5 times, respectively. When the expression levels were checked using GABAA receptor antagonists, HLE showed similar levels to NOR, as the sleep duration was reduced by flumazenil (45.1%), a benzodiazepine antagonist.

CONCLUSIONS

HLE increased NREM sleep and significantly improved sleep behavior due to its action on the GABAA receptors. The collective findings suggest that HLE can be used as a novel sleep-enhancing agent in the pharmaceutical and food industries.

Spectral Analysis and Antiulcer Potential of Lactuca sativa through the Amelioration of Proinflammatory Cytokines and Apoptosis Markers

The objective of this study was to characterize the bioactive ingredients and antiulcer effects of Lactuca sativa leaves. Several bioactive chemicals were found in the cold methanolic extract of Lactuca sativa leaves after gas chromatography-mass spectrometry (GC-MS) research: 9,12-octadecadienoic acid (Z,Z)-, cyclononasiloxane, octadecamethyl-, n-hexadecanoic acid, Hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl, octadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl ester, 9-octadecenamide, (Z)-, hexadecanoic acid, stigmasterol, benzothiazole, ethyl iso-allocholate, and octacosane. Distinct fingerprint regions in GCMS indicated the existence of bioactive compounds. The leaf powder of Lactuca sativa (LPL) demonstrated substantial antiulcer properties at 400 mg/kg, which was almost equivalent to the standard drug at 20 mg/kg. The cytokine network was efficiently regulated by reducing the production of proinflammatory cytokines such as IL-1β, IL-6, and TNF-α. The levels of caspase-3 and caspase-9 were also considerably lowered at p < 0.05 significant level.

Lettuce as an Effective Remedy in Uremic Pruritus: Review of the Literature Supplemented by an In Silico Study

Uremic pruritus is a frequent and prominent symptom in patients with advanced or end-stage renal disease. Lack of an effective treatment for kidney disease-associated pruritus often leads to many problems for these patients and makes it difficult to choose an appropriate treatment. The purpose of this evidence-based hypothesis is to share the scientific reasons and related mechanisms in order to claim that lettuce could be useful in the treatment of uremic pruritus. This hypothesis is based on studies related to lettuce and its anti-inflammatory, antioxidant, antidiabetic, sedative, hypnotic, nephroprotective, potassium balancing, and blood purification properties. As a result, we suggest that lettuce could be a good choice for improving and reducing uremic pruritus due to its certain characteristics. Although proof of this hypothesis requires further clinical trial studies, this hypothesis can nevertheless lead to formulating an appropriate therapy for uremic-induced pruritus. By conducting a molecular docking study, we investigated the interactions between nineteen natural bioactive components of lettuce (Lactuca sativa L.) and human kappa opioid receptors. The in silico docking studies revealed that most of the ligands showed better antipruritic efficacy than gabapentin. Gamma-tocopherol, delta-tocopherol, and campesterol demonstrated the highest binding affinities toward the target protein.

Public health approach of Unani medicine to cope and stay safe in hot environmental conditions

The rising episodes of deadly heat waves have intensified the need for a heat protection strategy. The Unani system of medicine offers ways to stay healthy in different climatic conditions. Hence, this article aims to discuss the applicability of health protection measures suggested by Unani scholars for hot weather conditions in the light of current researches. The manual literature survey of classical Unani texts was conducted to collect information on health safety measures for hot weather. A substantial search of scientific databases such as "Google Scholar" and "Medline" for proposed measures in combination with "heat-stroke", "heat exhaustion" and "heat rash" was also conducted to identify their possible activity in heat-related illnesses. The guidelines for summer seasons in the classical Unani literature are described under the title tadābīr-i-mavsam. Unani scholars have discussed in detail the pathophysiological effects of heat and the measures to stay healthy by regulating the body system through lifestyle, diet and herbs. Most of the measures proposed by them are backed up by evidences. However, some measures have not yet been evaluated for their therapeutic or prophylactic efficacy in heat-related illnesses. On the basis of findings, the authors advocate the adoption of evidence-based measures and propose further investigation of those measures that are not well supported by the evidence or have not yet been evaluated.

An Evidence-Based Research on Botanical Sources for Oral Mucositis Treatment in Traditional Persian Medicine

BACKGROUND

Cancer is one of the most prevalent diseases associated with heavy complications in treatment. Mucotoxic cancer therapies such as head and neck radiotherapy and some of the chemotherapy agents may lead to oral mucositis. In addition to its economic consequences, mucositis also affects patients' quality of life. In Traditional Persian Medicine (TPM) manuscripts, several medicaments have been suggested for the treatment of mucositis.

OBJECTIVE

Considering the public welcome for herbal medicine, the current evidence-based review study is conducted to investigate the herbal remedies which have been proposed for oral mucositis in TPM.

METHODS

At first, a comprehensive survey was done on Qanon fi al-Teb, which is the most important textbook of TPM; then the scientific name of the herbs was authenticated according to the botanical textbooks. At last, data banks including Scopus, Pubmed, Web of science and Science direct were investigated for possible relevant properties of each medicinal plant in the literature.

RESULTS

In total, 30 herbs are introduced in this study. According to the registered documents, 18 herbs are reported to have antioxidant, anti-inflammatory, antimicrobial, anti-nociceptive and wound healing properties of which the therapeutic effect of only a few herbs including Glycyrrhiza glabra, Malva sylvestris, Morus nigra, Punica granatum, and Solanum nigrum were directly evaluated against oral mucositis on the literature.

CONCLUSION

Despite the lack of human studies on mucositis for the other discussed herbs, their related pharmacological properties can be considered for new natural drug discovery supported by medieval and traditional experiments.

Applications of Sesquiterpene Lactones: A Review of Some Potential Success Cases

Sesquiterpene lactones, a vast range of terpenoids isolated from Asteraceae species, exhibit a broad spectrum of biological effects and several of them are already commercially available, such as artemisinin. Here the most recent and impactful results of in vivo, preclinical and clinical studies involving a selection of ten sesquiterpene lactones (alantolactone, arglabin, costunolide, cynaropicrin, helenalin, inuviscolide, lactucin, parthenolide, thapsigargin and tomentosin) are presented and discussed, along with some of their derivatives. In the authors’ opinion, these compounds have been neglected compared to others, although they could be of great use in developing important new pharmaceutical products. The selected sesquiterpenes show promising anticancer and anti-inflammatory effects, acting on various targets. Moreover, they exhibit antifungal, anxiolytic, analgesic, and antitrypanosomal activities. Several studies discussed here clearly show the potential that some of them have in combination therapy, as sensitizing agents to facilitate and enhance the action of drugs in clinical use. The derivatives show greater pharmacological value since they have better pharmacokinetics, stability, potency, and/or selectivity. All these natural terpenoids and their derivatives exhibit properties that invite further research by the scientific community.

Sedative Effects of Latexes Obtained from Some Lactuca L. Species Growing in Turkey

Lactuca L. species belong to the Asteraceae family and these plants are traditionally used for therapeutic purposes around the world. The dried milky latex of L. serriola is known as "lettuce oil" and is used as a sedative in Turkey. This study aimed to evaluate the sedative effects and analyze the chemical compositions of latexes obtained from some Lactuca species growing in Turkey. The sedative effects were evaluated through various behavioral tests on mice. For this purpose, latexes were obtained from L. glareosa Boiss., L. viminea (L.) J. Presl and C. P, L. mulgedioides (Vis and Panćić) Boiss. and Kotschy ex. Boiss., L. saligna L., and L. serriola L. The latex from L. saligna showed the highest sedative effects, whilst L. serriola and L. viminea latexes also displayed significant sedative effects compared to the control group at a dose of 100 mg/kg. However, the latexes from L. glareosa and L. mulqedioides did not exhibit any sedative effects on mice. Characteristic sesquiterpene lactones (lactucin, lactucopicrin, 11,13β-dihydrolactucin, and 11,13β-dihydrolactucopicrin) were determined qualitatively and quantitatively by high-performance liquid chromatography (HPLC). Lactucin was identified as the main component.

Neutralization of a bothropic PLA2-like protein by caftaric acid, a novel potent inhibitor of ophidian myotoxicity

Envenoming by snakebite is an important global health issue that has received little attention, leading the World Health Organization to naming it as neglected tropical disease. Several snakebites present serious local symptoms manifested on victims that may not be efficiently neutralized by serum therapy. Phospholipase A₂-like (PLA₂-like) toxins are present in Viperidae venoms and are responsible for local myotoxic activity. Herein, we investigated the association between BthTX-I toxin and caftaric acid (CFT), a molecule present in plants. CFT neutralized neuromuscular blocking and muscle-damaging activities promoted by BthTX-I. Calorimetric and light-scattering assays demonstrated that CFT inhibitor interacted with dimeric BthTX-I. Bioinformatics simulations indicated that CFT inhibitor binds to the toxin's hydrophobic channel (HCh). According to the current myotoxic mechanism, three different regions of PLA₂-like toxins have specific tasks: protein allosteric activation (HCh), membrane dockage (MDoS), and membrane rupture (MDiS). We propose CFT inhibitor interferes with the allosteric activation, which is related to the conformation change leading to the exposure/alignment of MDoS/MDiS region. This is the first report of a PLA₂-like toxin fully inhibited by a compound that interacts only with its HCh region. Thus, CFT is a novel candidate to complement serum therapy and improve the treatment of snakebite.

Bridging the Reciprocal Gap between Sleep and Fruit and Vegetable Consumption: A Review of the Evidence, Potential Mechanisms, Implications, and Directions for Future Work

A substantial burden of disease and mortality globally is attributable to both sleep disruption and low intakes of fruit and vegetable (FV) and there is increasing mechanistic and epidemiological evidence to support a reciprocal relationship between the two. This review provides an overview of experimental and observational studies assessing the relations between sleep and FV consumption from 52 human adult studies. Experimental studies are currently limited and show inconsistent results. Observational studies support a non-linear association with adults sleeping the recommended 7–9 hours/day having the highest intakes of FV. The potential mechanisms linking sleep and FV consumption are highlighted. Disrupted sleep influences FV consumption through homeostatic and non-homeostatic mechanisms. Conversely, FV consumption may influence sleep through polyphenol content via several potential pathways. Few human experimental studies have examined the effects of FV items and their polyphenols on sleep and there is a need for more studies to address this. An appreciation of the relationship between sleep and FV consumption may help optimize sleep and FV consumption and may reduce the burden of chronic diseases. This review provides implications for public health and directions for future work.

Effectiveness of the Sleep Enhancement by Green Romaine Lettuce (Lactuca sativa) in a Rodent Model

This study was conducted to investigate the effects of the extracts of green romaine lettuce (GRE) on sleep enhancement. GRE contains 1071.7 and 199.2 µg/g of extracts of lactucin and lactucopicrin, respectively, known as sleep enhancement substances. When 100 mg/kg of GRE was administered orally, sleep latency and duration time were significantly increased compared to controls (p < 0.05). Rapid eye movement (REM) sleep decreased with 100 mg/kg of GRE administration and non-REM (NREM) sleep also increased. There was no significant difference between REM and NREM among the oral GRE administration groups receiving 100, 120, and 160 mg/kg GRE. In the caffeine-induced insomnia model, total sleep time was significantly increased by 100 mg/kg GRE administration compared to the caffeine-treated group (p < 0.05). In addition, GRE inhibited the binding of [3H]-flumazenil in a concentration-dependent manner, and affinity of both lactucin and lactucopicrin to gamma-aminobutyric acid (GABA)A-benzodiazepine (BDZ) receptor was 80.7% and 55.9%, respectively. Finally, in the pentobarbital-induced sleep mouse model, the sleep enhancement effect of GRE was inhibited by flumazenil, an antagonist of BDZ. Thus, these results demonstrate that GRE acts via a GABAergic mechanism to promote sleep in a rodent model.

Romaine Lettuce/Skullcap Mixture Improves Sleep Behavior in Vertebrate Models

The aim of this study is to investigate the effects of romaine lettuce leaves extract (RE), skullcap root extract (SE) and their mixture on sleep behaviors in vertebrate models. HPLC analysis showed that RE contains lactucopicrin (0.02±0.01 mg/g extract), chlorogenic acid (4.05±0.03 mg/g extract), caffeic acid (2.38±0.03 mg/g extract), and chicoric acid (7.02±0.32 mg/g extract) as main phenolic compounds, while SE includes baicalin (99.4±0.5 mg/g extract), baicalein (8.28±0.21 mg/g extract), and wogonin (3.09±0.32 mg/g extract). The mixture of RE (100 mg/g extract) and SE (40 mg/g extract) increased total sleep time by 50.9% compared with the control in pentobarbital-induced sleep model. In electroencephalography (EEG) analysis, RE/SE mixture significantly increased Non-Rapid Eye Movement (NREM), in which delta wave was enhanced by around 40% compared with normal control, leading to the increase of sleep time. In caffeine-induced wake model, RE/SE mixture greatly decreased (53%) caffeine-induced wake time, showing a similar level to normal control. In addition, caffeine-induced decreased of NREM and delta wave effectively increased with RE/SE mixture; NREM and delta wave increased by 85% and 108%, respectively. Furthermore, RE/SE mixture was shown to bind to a gamma-aminobutyric acid type A (GABAA)-benzodiazepine (BZD) receptor stronger than RE or SE single extract. Taken together, RE/SE mixture effectively improved sleep behavior with the increase of NREM via GABAA-BZD receptor binding. RE/SE mixture can be used as an herbal agent for sleep disorders.