Evaluation of the Antinociceptive Activity ofOcimum gratissimumL. (Lamiaceae) Essential Oil and its isolated Active Principles in Mice

Chemical Composition, Analgesic and Anti-Inflammatory Activity of Pelargonium peltatum Essential Oils from Eastern Cape, South Africa

Pelargonium species are native to South Africa, and they have a long history in medicinal use. This study aimed to extract essential oils from different parts of P. peltatum, determine the chemical composition of the essential oils, and assess the essential oils' biological potential as analgesic and anti-inflammatory agents. The essential oils were obtained by hydro-distilling different parts of P. peltatum, and the essential profile was determined by GC-FID and GC-MS. The analgesic activity of the essential oil was determined by using a tail immersion in hot water method in rats, whereas the anti-inflammatory activity of the essential oils was assessed according to right hind paw oedema induced by egg albumin; the three doses selected for each experiment were 100, 200, and 400 mg/kg. According to the GC-FID and GC-MS analysis, camphene (3.6-33.4%), α-terpineol (4.8-19.1%), α-thujone (1.5-15.6%), piperitone (0.9-12.2%), linalool (1.6-11.7%), myrcene (5.2-10.7%), germacrene D (3.7-10.4%), β-caryophyllene (1.2-9.5%), β-cadinene (3.4-6.7%), and β-bourbonene (4.2-6.2%) were some of the major compounds identified in the oil. P. peltatum essential oils demonstrated analgesic activity by increasing pain latency in hot water; furthermore, in an inflammation test, the essential oil reduced the egg-albumin-induced paw oedema in both the first and second phases. Therefore, the current findings suggest that P. peltatum essential oils have analgesic and anti-inflammatory properties.

Anti-Inflammatory and Analgesic Properties of the Cannabis Terpene Myrcene in Rat Adjuvant Monoarthritis

Cannabis-based terpenes are believed to modulate physiological responses to disease and alter the efficacy of cannabinoids in the so-called “entourage effect”. The monoterpene myrcene can reduce nociception produced by noxious thermal and mechanical stimuli as well as reducing acute inflammation. The current study examined the role of myrcene and cannabidiol (CBD) in controlling chronic joint inflammation and pain. Chronic arthritis was induced in male Wistar rats by intra-articular injection of Freund’s complete adjuvant into the right knee. On days 7 and 21 after arthritis induction, joint pain (von Frey hair algesiometry), inflammation (intravital microscopy, laser speckle contrast analysis) and joint histopathology were assessed. Local application of myrcene (1 and 5 mg/kg s.c.) reduced joint pain and inflammation via a cannabinoid receptor mechanism. The combination of myrcene and CBD (200 μg) was not significantly different from myrcene alone. Repeated myrcene treatment had no effect on joint damage or inflammatory cytokine production. These data suggest that topical myrcene has the potential to reduce chronic arthritis pain and inflammation; however, it has no synergistic effect with CBD.

Antinociceptive effects of minor cannabinoids, terpenes and flavonoids in Cannabis

Cannabis has been used for centuries for its medicinal properties. Given the dangerous and unpleasant side effects of existing analgesics, the chemical constituents of Cannabis have garnered significant interest for their antinociceptive, anti-inflammatory and neuroprotective effects. To date, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) remain the two most widely studied constituents of Cannabis in animals. These studies have led to formulations of THC and CBD for human use; however, chronic pain patients also use different strains of Cannabis (sativa, indica and ruderalis) to alleviate their pain. These strains contain major cannabinoids, such as THC and CBD, but they also contain a wide variety of cannabinoid and noncannabinoid constituents. Although the analgesic effects of Cannabis are attributed to major cannabinoids, evidence indicates other constituents such as minor cannabinoids, terpenes and flavonoids also produce antinociception against animal models of acute, inflammatory, neuropathic, muscle and orofacial pain. In some cases, these constituents produce antinociception that is equivalent or greater compared to that produced by traditional analgesics. Thus, a better understanding of the extent to which these constituents produce antinociception alone in animals is necessary. The purposes of this review are to (1) introduce the different minor cannabinoids, terpenes, and flavonoids found in Cannabis and (2) discuss evidence of their antinociceptive properties in animals.

A review on the traditional uses, phytochemistry, and pharmacological activities of clove basil (Ocimum gratissimum L.)

In traditional medicine, Ocimum gratissimum (clove basil) is used in the treatment of various diseases such as diabetes, cancer, inflammation, anaemia, diarrhoea, pains, and fungal and bacterial infections. The present study reviewed the phytochemicals, essential oils, and pharmacological activities of O. gratissimum. The bioactive compounds extracted from O. gratissimum include phytochemicals (oleanolic acid, caffeic acid, ellagic acid, epicatechin, sinapic acid, rosmarinic acid, chlorogenic acid, luteolin, apigenin, nepetoidin, xanthomicrol, nevadensin, salvigenin, gallic acid, catechin, quercetin, rutin, and kaempfero) and essential oils (camphene, β-caryophyllene, α- and β-pinene, α-humulene, sabinene, β-myrcene, limonene, 1,8-cineole, trans-β-ocimene, linalool, α- and δ-terpineol, eugenol, α-copaene, β-elemene, p-cymene, thymol, and carvacrol). Various in vivo and in vitro studies have shown that O. gratissimum and its bioactive constituents possess pharmacological properties such as antioxidant, anti-inflammatory, anticancer, hepatoprotective, antidiabetic, antihypertensive, antidiarrhoeal, and antimicrobial properties. This review demonstrated that O. gratissimum has a strong preventive and therapeutic effect against several diseases. The effectiveness of O. gratissimum to ameliorate various diseases may be attributed to its antimicrobial and antioxidant properties as well as its capacity to improve the antioxidant systems. However, despite the widespread pharmacological activities of O. gratissimum, further experiments in human clinical trial studies are needed to establish effective and safe doses for the treatment of various diseases.

Analgesic Potential of Terpenes Derived from Cannabis sativa

Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.

Bioguided identification of pentacyclic triterpenoids as anti-inflammatory bioactive constituents of Ocimum gratissimum extract

ETHNOPHARMACOLOGICAL RELEVANCE

Ocimum gratissimum is a plant spice widely used in African traditional medicine to treat pain-related conditions. However, the anti-inflammatory mechanisms underlying this activity and the main active ingredients in O. gratissimum have not yet been fully characterized.

AIM OF THE STUDY

To isolate and identify the main anti-inflammatory active constituents of Ocimum gratissimum extract and their underlying mechanisms in murine macrophages.

MATERIAL AND METHODS

Chromatographic techniques and spectroscopic data were used for compounds isolation and identification. Inflammatory conditions were produced in cultured RAW 264.7 macrophage cells by the application of lipopolysaccharide (LPS). The WST-1 assay was used to evaluate the cell viability, and the nitric oxide production was quantified by the Griess reagent method. The fluorometric cyclooxygenase (COX) activity assay kit was used to assess the activity of COX-1 and COX-2 enzymes. The levels of IFN-γ, TNF-α, IL-2, IL-4, IL-6, and IL-10 cytokines and the apoptosis-inducing effect were measured by flow cytometer using the cytometric Bead Array (CBA) Human Th1/Th2 Cytokine Kit II and FITC Annexin V Apoptosis Detection kit, respectively.

RESULTS

The results showed that the extract and fractions of Ocimum gratissimum inhibit nitric oxide production and the proliferation of Raw 264.7 macrophage cells. The bioguided fractionation led to the identification of pentacyclic triterpenes as anti-inflammatory bioactive compounds. Pomolic and tormentic acids being the most active, inhibiting the secretion of IFN-γ cytokine, COX enzyme, and inducing apoptosis in activated Raw 264.7 macrophage cells.

CONCLUSIONS

This study revealed that pomolic and tormentic acids are the main active principles responsible at least in part for the anti-inflammatory effect of the extract of Ocimum gratissimum. Besides of providing more evidence for the traditional use of Ocimum gratissimum against inflammatory disorders, this study reveals the multitarget potential of pomolic and tormentic acids as promising future drugs against inflammatory diseases.

Antinociceptive Effect of an Aqueous Extract and Essential Oil from Baccharis heterophylla

Infusions and poultices prepared from the aerial parts of Baccharis heterophylla Kunth (Asteraceae) are widely used in Oaxaca (Mexico) for relieving painful and inflammatory complaints. Therefore, the antinociceptive potential of an aqueous extract (31.6–316 mg/kg, p.o.) and essential oil (30–177 µg/paw, i.pl.) of the plant was assessed using the formalin test. Both preparations inhibited the formalin-induced nociception response (100–316 mg/kg and 100–177 µg/paw, respectively) during the test’s second phase. Chemical analysis of the aqueous extract revealed that the major active components were chlorogenic acid (1), 3,4-di-O-(E)-caffeoylquinic acid (2), 3,5-di-O-(E)-caffeoylquinic acid (3), 4,5-di-O-(E)-caffeoylquinic acid (4), 3,5-di-O-(E)-caffeoylquinic acid methyl ester (5), apigenin (6), genkwanin (7), acacetin (8). Compounds 1–5 and 8 are new for B. heterophylla. A high-pressure liquid chromatographic method for quantifying chlorogenic acid (1) and di-caffeoylquinic acids 2–4 in the plant was developed and validated. Analyses of the essential oil and the headspace solid-phase microextraction products, via gas-chromatography-mass spectrometry, revealed that the major volatiles were β-pinene, myrcene, D-limonene, β-caryophyllene, and α-caryophyllene, which have demonstrated antinociceptive properties.

COVID-19: Is There Evidence for the Use of Herbal Medicines as Adjuvant Symptomatic Therapy?

BACKGROUND

Current recommendations for the self-management of SARS-Cov-2 disease (COVID-19) include self-isolation, rest, hydration, and the use of NSAID in case of high fever only. It is expected that many patients will add other symptomatic/adjuvant treatments, such as herbal medicines.

AIMS

To provide a benefits/risks assessment of selected herbal medicines traditionally indicated for "respiratory diseases" within the current frame of the COVID-19 pandemic as an adjuvant treatment.

METHOD

The plant selection was primarily based on species listed by the WHO and EMA, but some other herbal remedies were considered due to their widespread use in respiratory conditions. Preclinical and clinical data on their efficacy and safety were collected from authoritative sources. The target population were adults with early and mild flu symptoms without underlying conditions. These were evaluated according to a modified PrOACT-URL method with paracetamol, ibuprofen, and codeine as reference drugs. The benefits/risks balance of the treatments was classified as positive, promising, negative, and unknown.

RESULTS

A total of 39 herbal medicines were identified as very likely to appeal to the COVID-19 patient. According to our method, the benefits/risks assessment of the herbal medicines was found to be positive in 5 cases (Althaea officinalis, Commiphora molmol, Glycyrrhiza glabra, Hedera helix, and Sambucus nigra), promising in 12 cases (Allium sativum, Andrographis paniculata, Echinacea angustifolia, Echinacea purpurea, Eucalyptus globulus essential oil, Justicia pectoralis, Magnolia officinalis, Mikania glomerata, Pelargonium sidoides, Pimpinella anisum, Salix sp, Zingiber officinale), and unknown for the rest. On the same grounds, only ibuprofen resulted promising, but we could not find compelling evidence to endorse the use of paracetamol and/or codeine.

CONCLUSIONS

Our work suggests that several herbal medicines have safety margins superior to those of reference drugs and enough levels of evidence to start a clinical discussion about their potential use as adjuvants in the treatment of early/mild common flu in otherwise healthy adults within the context of COVID-19. While these herbal medicines will not cure or prevent the flu, they may both improve general patient well-being and offer them an opportunity to personalize the therapeutic approaches.

Assessment of Pain Associated with the Injection of Sodium Pentobarbital in Laboratory Mice (Mus musculus)

The AVMA Guidelines for the Euthanasia of Animals considers injection of barbiturates to be an acceptable method of euthanasia in rodents but states there is a potential for pain when administered intraperitoneally. This study examined the potential for pain in mice by assessing visceral pain after intraperitoneal administration and acute pain by using a paw-lick test. Male and female mice (n = 160) intraperitoneally received a euthanizing dose of sodium pentobarbital at a concentration of 5, 50, or 390 mg/mL and were observed for writhing, peritoneum-directed behaviors (PDB), loss of righting reflex, and time to death. Writhing was not observed in any animal. There was no significant difference in the number of mice exhibiting PDB or in the rate of PDB for responders receiving either saline or the 390-mg/mL solution. There was a significant treatment effect on time, with greater concentration and dose resulting in more rapid loss of righting reflex and death. In the second set of experiments, the same solutions were injected subcutaneously into the plantar hindpaw of male and female mice (n = 84). The number of responders, latency until the first lick, and the number of licks per responder were recorded. The number of responders was increased in the 50-mg/mL group; however, there was no difference in latency or the number of licks per responder. These results show that intraperitoneal injection of sodium pentobarbital for euthanasia in mice did not result in increased behavioral signs of pain, and animals lose consciousness more rapidly than the onset of pain seen in the pawlick test. Therefore, although sodium pentobarbital is capable of inducing inflammation, euthanasia through intraperitoneal administration is rapid and does not result in overt signs of pain when compared with injection of saline.

Medicinal Plants Used in the Treatment of Mental and Neurological Disorders in Ghana

Ethnopharmacological Relevance

Mental and neurological disorders are a serious public health challenge globally, particularly in developing countries where cultural factors and limited access to standard healthcare have led to a reliance on traditional medicines. However, ethnopharmacological characterization of traditional medicines used to treat these diseases is lacking. In this study, an ethnobotanical description of plant species used in treating mental and neurological disorders in Ghana and an update of their experimentally validated pharmacological relevance are provided.

Materials and Methods

Two hundred herbalists agreed to participate but sixty-six specialized in treating mental and neurological disorders were interviewed on their traditional medical practice. Literature review was conducted to verify the experimentally validated pharmacological importance of the reported plants.

Results

Thirty-two plant species belonging to twenty-eight families were identified. Most plant species had either analgesic (50%), anxiolytic (18.8%), or anticonvulsant (15.6%) properties. Others had reported sedative, anti-Alzheimer's disease, motor coordination, antipsychotic, antidepressant, cognitive enhancement, and neuroprotective properties. While Ageratum conyzoides L. (Asteraceae) and Ocimum gratissimum L. (Lamiaceae) were the most commonly mentioned species with analgesic properties, Lantana camara L. (Verbenaceae) was the most-reported anxiolytic product, with Cymbopogon citratus DC. (Gramineae), Mangifera indica L., Tetrapleura tetraptera Schum Taub. (Fabaceae), and Persea Americana Mill (Lauraceae) being the most studied anticonvulsants.

Conclusions

This study provides the first report specifically on medicinal plants used in treating mental and neurological disorders in Ghana. Most of the identified plants have been scientifically confirmed to possess neuro- and psychopharmacological properties and may serve as templates for drug development.

Medicinal Plants of the Family Lamiaceae in Pain Therapy: A Review

Recently, numerous side effects of synthetic drugs have lead to using medicinal plants as a reliable source of new therapy. Pain is a global public health problem with a high impact on life quality and a huge economic implication, becoming one of the most important enemies in modern medicine. The medicinal use of plants as analgesic or antinociceptive drugs in traditional therapy is estimated to be about 80% of the world population. The Lamiaceae family, one of the most important herbal families, incorporates a wide variety of plants with biological and medical applications. In this study, the analgesic activity, possible active compounds of Lamiaceae genus, and also the possible mechanism of actions of these plants are presented. The data highlighted in this review paper provide valuable scientific information for the specific implications of Lamiaceae plants in pain modulation that might be used for isolation of potentially active compounds from some of these medicinal plants in future and formulation of commercial therapeutic agents.

Characterization of essential oil from Ocimum gratissimum leaves: Antibacterial and mode of action against selected gastroenteritis pathogens

Essential oil of fresh leaves of Ocimum gratissimum (OGEO) was water-steam distilled and analyzed by GC-MS. Thirty-seven compounds were identified, with eugenol (55.6%) as the major component followed by cis-ocimene (13.9%), γ-muurolene (11.6%), (Z,E)-α-farnesene (5.6%), α-trans-bergamotene (4.1%), and β-caryophyllene (2.7%). Antimicrobial activity of OGEO was tested against four gastroenteritis pathogens (Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Shigella flexneri). OGEO exhibited antibacterial effect, with MICs of 1-2 mg ml^-1, against the tested species. OGEO also displayed rapid killing effect within 5 s at four times of MIC against both E. coli and S. Typhimurium. Various assays were performed to investigate the mode of action of the oil. OGEO increased the permeability of microbial cell membrane as evidenced by LIVE/DEAD BacLight assay. Analyses of the release of absorbing materials at 260 nm, protein leakage, SDS-PAGE, and SEM strongly suggested the disruptive action of the oil on the cytoplasmic membrane of the tested microorganisms. Results revealed that the antibacterial property of OGEO could be due to membrane disruption.

Ocimum gratissimum L. leaf flavonoid-rich fraction suppress LPS-induced inflammatory response in RAW 264.7 macrophages and peritonitis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Ocimum gratissimum L. is a herbaceous plant that has been reported in several ethnopharmacological surveys as a plant readily accessible to the communities and widely used for the treatment of inflammatory diseases. The main goal of this study was to investigate the in vitro and in vivo anti-inflammatory activity and mechanism of action of the ethylacetate fraction of O. gratissimum leaf (EAFOg) and to chemically characterize this fraction.

MATERIALS AND METHODS

EAFOg was obtained from a sequential methanol extract. The safety profile was evaluated on RAW 264.7 cells, using the alamarBlue® assay. Phenolic contents were determined by spectrophotometry, and metabolites quantified by high performance liquid chromatography. The anti-inflammatory activity of EAFOg and its ability to acts on leucocytes infiltration, inflammatory mediators as NO, IL-1β, TNF-α, and IL-10 in lipopolysaccharide-induced peritonitis in mice and LPS-stimulated RAW 264.7 macrophage were evaluated. In addition, the anti-inflammatory activity of EAFOg was also investigated in arachidonic acid-related enzymes.

RESULTS

Total phenolic and flavonoid contents of EAFOg were 139.76±1.07mg GAE/g and 109.95±0.05mg RE/g respectively. HPLC analysis revealed the presence of rutin, ellagic acid, myricetin and morin. The fraction exhibited no cytotoxic effects on the RAW 264.7 cells. The EAFOg (10, 50 and 200mg/kg) significantly reduced (p<0.05) neutrophils (38.8%, 58.9%, and 66.5%) and monocytes (38.9%, 58.0% and 72.8%) in LPS-induced peritonitis. Also, EAFOg (5, 20 and 100µg/mL) produced significant reduction in NO, IL-1β, and TNF-α in RAW 264.7 cells. However, IL-10 level was not affected by the EAFOg, and it preferentially inhibits COX-2 (IC₅₀ =48.86±0.02µg/mL) than COX-1 and 15-LO (IC₅₀ >100µg/mL).

CONCLUSION

The flavonoid-rich fraction of O. gratissimum leaves demonstrated anti-inflammatory activity via mechanisms that involves inhibition of leucocytes influx, NO, IL-1β, and TNF-α in vivo and in vitro, thus supporting its therapeutic potential in slowing down inflammatory processes in chronic diseases.

Analgesic Potential of Essential Oils

Pain is an unpleasant sensation associated with a wide range of injuries and diseases, and affects approximately 20% of adults in the world. The discovery of new and more effective drugs that can relieve pain is an important research goal in both the pharmaceutical industry and academia. This review describes studies involving antinociceptive activity of essential oils from 31 plant species. Botanical aspects of aromatic plants, mechanisms of action in pain models and chemical composition profiles of the essential oils are discussed. The data obtained in these studies demonstrate the analgesic potential of this group of natural products for therapeutic purposes.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Anti-inflammatory, Anti-nociceptive and Total polyphenolic Content of Hydroethanolic Extract of Ocimum gratissimum L. Leaves

Ocimum gratissimum has been reported in several ethnopharmacological surveys as a plant readily accessible to the communities and widely used with a lot of therapeutic potentials. In this study, we aimed to experimentally evaluate the anti-inflammatory effects of hydro-ethanolic extract in animal models of inflammation and nociception and membrane stabilization assay. O gratissimum leaves hydroethanolic extract was subjected to phytochemical screening and spectrophotometric quantification of polyphenolics. The extract was investigated for anti-inflammatory effects in carrageenan -induced paw oedema and cotton pellet - induced granuloma in rats. The antinociceptive effects were investigated in acetic acid -induced writhing in mice and formalin test in rats. Animals were randomly divided into groups; negative control, extract treated (200 -800 mg/kg) and indomethacin (10 mg/kg) standard reference groups. In- vitro anti-inflammatory activity was performed by testing for membrane stability in heat/hypotonic solution -induced rat erythrocytes destabilization assay. Phytochemical screening revealed presence of saponins, tannins, alkaloids, flavonoids, terpenoids, and cardenolides. Quantification of the polyphenolic content revealed the presence of appreciable quantities of phenolics and flavonoids. Carrageenan-induced paw oedema, cotton-pellet granuloma, acetic acid -induced writhing and formalin induced paw licking tests showed that hydroethanolic extract of O gratissimum possess anti-inflammatory and anti-nociceptive effects. The extract did not induce gastric lesion formation in stomach of cotton-pellet granuloma rats. The extract was more efficient at reducing membrane destabilization than indomethacin in the membrane stability assay. These results suggest that hydroethanolic extract of O gratissimum leaves exhibits anti-inflammatory and anti-nociceptive effects in the animals.