Evaluation of chemical composition and antiedematogenic activity of the essential oil of Hyptis martiusii Benth

Rational design of 2-benzylsulfinyl-benzoxazoles as potent and selective indoleamine 2,3-dioxygenase 1 inhibitors to combat inflammation

Mimicking the transition state of tryptophan (Trp) and O2 in the enzymatic reaction is an effective approach to design indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors. In this study, we firstly assembled a small library of 2-substituted benzo-fused five membered heterocycles and found 2-sulfinyl-benzoxazoles with interesting IDO1 inhibitory activities. Next the inhibitory activity toward IDO1 was gradually improved. Several benzoxazoles showed potent IDO1 inhibitory activity with IC50 of 82-91 nM, and exhibited selectivity between IDO1 and tryptophan 2,3-dioxygenase (TDO2). Enzyme binding studies showed that benzoxazoles are reversible type II IDO1 inhibitors, and modeling studies suggested that the oxygen atom of the sulfoxide in benzoxazoles interacts with the iron atom of the heme group, which mimics the transition state of Fe-O-O-Trp complex. Especially, 10b can effectively inhibit the NO production in lipopolysaccharides (LPS) stimulated RAW264.7 cells, and it also shows good anti-inflammation effect on mice acute inflammation model of croton oil induced ear edema.

Phytochemistry and Evaluation of the Anti-Inflammatory Activity of the Hydroethanolic Extract of Virola elongata (Benth.) Warb. Stem Bark

BACKGROUND

Previous studies of the hydroethanolic extract of Virola elongata inner stem bark (HEVe) have demonstrated its antioxidant, gastroprotective, and antiulcer properties, but have not evaluated its anti-inflammatory potential.

METHODS

HEVe was obtained by maceration and phytochemically analyzed. Its systemic anti-inflammatory activity was assessed by its effect on lipopolysaccharide (LPS)-induced peritonitis in mice. HEVe gel (HEgVe) was employed to evaluate topical anti-inflammatory activity by measuring the ear edema resulting from croton-oil-induced dermatitis in mice. A cell viability assay was conducted to determine the non-cytotoxic concentrations of the HEVe. RAW 264.7 cells were stimulated by LPS to determinate cytokine and nitric oxide production.

RESULTS

A phytochemical analysis of the HEVe revealed the presence of phenolic acids, neolignans, flavonoids, and monomeric catechins. The oral treatment of acute peritonitis with HEVe reduced the total leukocytes, neutrophils, TNF-α, and IL-1β and elevated IL-10 levels. The application of the HEgVe reduced local edema. The HEVe on the RAW 264.7 cells exhibited no cytotoxicity, and the cells with HEVe displayed reduced TNF-α, IL-1β, and NO levels and increased IL-13 levels.

CONCLUSIONS

HEVe demonstrated systemic and topical multitarget anti-inflammatory activity, likely due to the combined effects of secondary metabolites. HEVe emerges as a promising herbal remedy for inflammation with minimal cytotoxicity, emphasizing its potential therapeutic significance.

Topical Antiedematogenic Activity of the Essential Oil of Psidium brownianum Mart. (OEPB) in Murine Ear Edema Models

Psidium brownianum Mart is reported in the literature by antinociceptive and antioxidant activities, indicating that this species' secondary metabolites might be used to control inflammatory processes. The present study aimed to characterize the topical antiedematogenic activity of the essential oil of Psidium brownianum Mart. (OEPB) in ear edema models by different inflammatory agents. Female Swiss mice (25-35 g) and Wistar albino rats (200-300 g) were used throughout tests (n=6/group) on acute or chronic edema models induced by single and multiple topical applications. The OEPB is administered topically pure or at a concentration of 100 or 200 mg/mL. The antiedematogenic mechanism of OEPB was analyzed by administering capsaicin, arachidonic acid, histamine, and phenol at the best effective dose (200 mg/mL). The results showed a significant reduction of edema-induced single (28.87 %) and multiple (50.13 %) applications of croton oil compared to the negative control group. Regarding potential mechanisms of action, OEPB (200 mg/mL) inhibited the development of edema triggered by capsaicin (29.95 %), arachidonic acid (22.66 %), phenol (23.35 %), and histamine (75.46 %), suggesting an interference with the histaminergic pathway. These results indicate that OEPB presents a topical antiedematogenic effect in acute and chronic murine models, possibly interfering with inflammatory pathways triggered by mediators such as histamine.

Anti-inflammatory, healing and antiophidic potential of Jatropha mollissima (Pohl) Baill. (Euphorbiaceae): From popular use to pharmaceutical formulation in gel

Jatropha mollissima (Pohl) Baill. (Euphorbiaceae) is widely used in traditional medicine to treat inflammatory disorders. So, a topical gel containing the hydroethanolic extract of its leaves was developed and evaluated for its anti-inflammatory, wound healing, and antiophidic properties in mice. First, the chemical profile of different parts of the plant was characterized by liquid chromatography coupled to mass spectrometry (LC-MS) using molecular networking. In the leaf extract, 11 compounds were characterized, with a particular emphasis on the identification of flavonoids. The gel efficiently inhibited carrageenan-induced paw edema, as well as acute and chronic croton oil-induced ear edema models, thereby reducing inflammatory and oxidative parameters in inflamed tissues. Besides anti-inflammatory activity, the herbal gel showed significant wound healing activity. The edematogenic, hemorrhagic and dermonecrotic activities induced by Bothrops jararaca snake venom were effectively inhibited by the treatment with J. mollissima gel. The association with the herbal gel improved in up to 90% the efficacy of commercial snake antivenom in reduce venom-induced edema. Additionally, while antivenom was not able to inhibit venom-induced dermonecrosis, treatment with herbal gel reduced in 55% the dermonocrotic halo produced. These results demonstrate the pharmacological potential of the herbal gel containing J. mollissima extract, which could be a strong candidate for the development of herbal products that can be used to complement the current antivenom therapy against snake venom local toxicity.

Lamiaceae Essential Oils, Phytochemical Profile, Antioxidant, and Biological Activities

Medicinal and aromatic plants present important active compounds that have potential for use in food, pharmaceutical, and agriculture industries. In this sense, the present work aimed to conduct a literature review on the potential applications of essential oils from Lamiaceae species. Antioxidant, anti-inflammatory, and antimicrobial activities were evaluated. The importance of this study is demonstrated as a way to theoretically provide information on the use of different plants belonging to the Lamiaceae family, especially with regard to the physical, chemical, and biological properties of its essential oils.

Anti-Inflammatory Comparison of Melatonin and Its Bromobenzoylamide Derivatives in Lipopolysaccharide (LPS)-Induced RAW 264.7 Cells and Croton Oil-Induced Mice Ear Edema

The pineal gland is a neuroendocrine organ that plays an important role in anti-inflammation through the hormone melatonin. The anti-inflammatory effects of melatonin and its derivatives have been reported in both in vitro and in vivo models. Our previous study reported the potent antioxidant and neuroprotective activities of bromobenzoylamide substituted melatonin. In silico analysis successfully predicted that melatonin bromobenzoylamid derivatives were protected from metabolism by CYP2A1, which is a key enzyme of the melatonin metabolism process. Therefore, the anti-inflammatory activities of melatonin and its bromobenzoylamide derivatives BBM and EBM were investigated in LPS-induced RAW 264.7 macrophages and croton oil-induced ear edema in mice. The experiments showed that BBM and EBM significantly reduced production of the inflammatory mediators interleukin-6 (IL-6), prostaglandin E2 (PGE₂), and nitric oxide (NO) in a dose-dependent manner, but only slightly affected TNF-α in LPS-induced RAW 264.7 macrophages. This suggests that modifying melatonin at either the N1-position or the N-acetyl side chain affected production of NO, PGE₂ and IL-6 in in vitro model. In the croton oil-induced mouse ear edema model, BBM, significantly decreased ear edema thickness at 2-4 h. It leads to conclude that bromobenzoylamide derivatives of melatonin may be one of the potential candidates for a new type of anti-inflammatory agent.

In-vivo anti-inflammatory activity and safety assessment of the aqueous extract of Algerian Erica arborea L. (Ericaceae) aerial parts

ETHNOPHARMACOLOGICAL RELEVANCE

Erica arborea known as Khlenj in Algeria is a small shrub belonging to Ericaceae family. E. arborea Aqueous extract (EAAE) is used in traditional medicine for anti-inflammatory, diuretic, antimicrobial, and antiulcer purposes.

AIM OF THE STUDY

To our knowledge, no data reveal the combination between in-vivo anti-inflammatory and toxicological studies of EAAE. For this purpose, the aim of this study is to evaluate the biological activity cited above and assess its safety.

MATERIAL AND METHODS

Anti-inflammatory activity was undergone using carrageenan-induced paw edema and croton oil-induced ear edema. The acute and sub-acute toxicity were conducted following the OECD guidelines 423 and 407, respectively. Phytochemical identification was carried out using HPLC-DAD-MS. Quantitative evaluation of polyphenols; flavonoids and antioxidant activity of EAAE were also determined.

RESULTS

Oral administration of EAAE (250 and 500 mg/kg) significantly (p < 0.05) reduced the edema induced by carrageenan. Administration of EAAE dosed at 250 and 500 mg/kg exhibited efficacy in reducing edema induced by croton oil. The acute administration of EAAE at doses of 2000 and 5000 mg/kg did not cause any mortality or adverse effects indicating that the LD50 is above 5000 mg/kg. The prolonged administration of EAAE (500 and 1000 mg/kg) showed a significant reduction in triglycerides levels in male and female rats whereas no significant changes in other biochemical and hematological parameters were observed. Histopathological damages were recorded in both liver and kidney animal's tissues of both sexes treated with medium and maximum doses of EAAE. Phytochemical characterization of EAAE revealed a high amount of phenolic compounds, HPLC-DAD-MS analysis led to the identification of chlorogenic acid and five flavonol glycosides: myricetin pentoside, quercetin-3-O-glucoside, myricetin-3-O-rhamnoside, quercetin-3-O-pentoside, and quercetin-3-O-rhamnoside.

CONCLUSION

In the light of the results obtained in this study, EAAE corroborates the popular use to treat the anti-inflammatory impairments. EAAE can be considered as non-toxic in acute administration and exhibited a moderate toxicity in sub-acute administration. High phenolic content and in-vitro antioxidant activity observed indicate that EAAE may reduce oxidative stress markers in-vivo.

Subtribe Hyptidinae (Lamiaceae): A promising source of bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

The subtribe Hyptidinae contains approximately 400 accepted species distributed in 19 genera (Hyptis, Eriope, Condea, Cantinoa, Mesosphaerum, Cyanocephalus, Hypenia, Hyptidendron, Oocephalus, Medusantha, Gymneia, Marsypianthes, Leptohyptis, Martianthus, Asterohyptis, Eplingiella, Physominthe, Eriopidion and Rhaphiodon). This is the Lamiaceae clade with the largest number of species in Brazil and high rates of endemism. Some species have been used in different parts of the world mainly as insecticides/pest repellents, wound healing and pain-relief agents, as well as for the treatment of respiratory and gastrointestinal disorders.

AIM OF THE REVIEW

This review aims to discuss the current status concerning the taxonomy, ethnobotanical uses, phytochemistry and biological properties of species which compose the subtribe Hyptidinae.

MATERIALS AND METHODS

The available information was collected from scientific databases (ScienceDirect, Pubmed, Web of Science, Scopus, Google Scholar, ChemSpider, SciFinder ACS Publications, Wiley Online Library), as well as other literature sources (e.g. books, theses).

RESULTS

The phytochemical investigations of plants of this subtribe have led to the identification of almost 300 chemical constituents of different classes such as diterpenes, triterpenes, lignans, α-pyrones, flavonoids, phenolic acids and monoterpenes and sesquiterpenes, as components of essential oils. Extracts, essential oils and isolated compounds showed a series of biological activities such as insecticide/repellent, antimicrobial and antinociceptive, justifying some of the popular uses of the plants. In addition, a very relevant fact is that several species produce podophyllotoxin and related lignans.

CONCLUSION

Several species of Hyptidinae are used in folk medicine for treating many diseases but only a small fraction of the species has been explored and most of the traditional uses have not been validated by current investigations. In addition, the species of the subtribe appear to be very promising as alternative sources of podophyllotoxin-like lignans which are the lead compounds for the semi-synthesis of teniposide and etoposide, important antineoplastic agents. Thus, there is a wide-open door for future studies, both to support the popular uses of the plants and to find new biologically active compounds in this large number of species not yet explored.

Macroscopic, biochemical and hystological evaluation of topical anti-inflammatory activity of Casearia sylvestris (Flacourtiaceae) in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammatory skin diseases presents high prevalence and lack of alternatives that can be used for self-care by the population. Casearia sylvestris is a plant used topically in different communities in Brazil, to treat wounds or promote cutaneous healing. To evaluate the topical anti-inflammatory activity for the crude hydroalcoholic extract of Casearia sylvestris (HCE-CS) in the models of single or multiple administration of chroton oil to induce ear edema in mice.

MATERIALS AND METHODS

Experimental study using male Swiss mice (25-35g) kept under constant conditions in the Laboratory of Experimental Neuroscience (LaNEx)-UNISUL. Edema was induced in both models, respectively, by the single or multiple application of croton oil (CO, 2.5%, in 20 μl) on the external surface of the ear. The different groups of animals (n = 8) received different treatments: vehicle, dexamethasone (DEXA) or different doses of HCE-CS. Edema was evaluated macroscopically for 6 h (early edema) or 8 days (late edema) after the first application of the CO and immediately after the animals were submitted to euthanasia for the collection of the samples (treated ears). For early edema, the tissue was biochemically evaluated for myeloperoxidase activity (MPO) and levels of nitrite/nitrate. In the late edema model, the ears were histologically evaluated for general morphometry, degranulated and non-degranulated mast cells, as well as acanthosis.

RESULTS

Topic treatment with HCE-CS significantly reduced the early and late edema, as well as MPO activity and tissue levels of nitrite/nitrate. Finally, in the late edema model there was a lower density of degranulated mast cells in relation to the vehicle treated group and decreased thickness of the epidermis (acanthosis).

CONCLUSION

These results suggest a possible benefit of topical treatment with HCE-CS in inflammatory conditions of the skin.

Toxicological and Pharmacological Activities of Leptohyptis macrostachys (Benth.) Harley and J.F.B.Pastore (Lamiaceae) on Intestinal Smooth Muscle

Leptohyptis macrostachys, previously known as Hyptis macrostachys Benth., is used in folk medicine to relieve the symptoms of asthma, cough, and bronchitis. Recently, we showed that the ethanol extract obtained from Leptohyptis macrostachys has selective spasmolytic activity on guinea pig ileum. Therefore, the aim of this study was to characterize the spasmolytic mechanism of this extract, investigated whether it presents toxicological and antidiarrheal activities. Therefore, the crude ethanolic extract of Leptohyptis macrostachys was analyzed by high-performance liquid chromatographic-diode array detection (HPLC-DAD). The spasmolytic effect was evaluated on guinea pig ileum, toxicological activity using rats and antidiarrheal activity using male and female mice. In HPLC-DAD analysis, Rosmarinic acid (5.44%) was the most abundant phenolic compound, being considered as a chemical marker. The spasmolytic potency of the extract on histamine-induced contraction was reduced in the presence of 1 mM TEA+, a selective big-conductance K+ channels blocker (BKCa). The extract produces a dose-dependent antidiarrheal activity, inhibiting equipotently defecation frequency and liquid stool formation. In addition, the extract has inhibited in a dose-dependent manner both castor oil-induced intestinal transit and intestinal fluid content. Thus, the spasmolytic activity of the extract involves positive modulation of BKCa and its antidiarrheal activity is related to inhibition of intestinal motility and secretion.

Essential oil of Pterodon polygalaeflorus Benth attenuates nociception in mice

Essential oils (EO) are volatile liquids responsible for the aroma of plants. Pterodon polygalaeflorus seeds have received widespread use in folk medicine for the treatment of inflammatory diseases. For this reason and because Pterodon polygalaeflorus seeds have great EO content, which is frequently pharmacologically active, the present study aimed to evaluate the antinociceptive effect of EO from Pterodon polygalaeflorus (EOPPgfl) and its acute toxic effects. The EEOPPgfl sample, which was extracted by steam distillation of the seeds, had a yield of 2.4% of the seeds weight and had, as major constituents, beta-elemene (48.19%), trans-caryophyllene (19.51%), and epi-bicyclosesquiphellandrene (12.24%). The EOPPgfl sample showed mild acute toxicity and its calculated median lethal dose (LD₅₀) was 3.38 g/kg. EOPPgfl (20–60 mg/kg) showed antinociceptive activity as evidenced by several tests and inhibited writhing induced by acetic acid. The maximum effect was obtained with the 30 mg/kg dose and at 60 min after its administration. EOPPgfl also decreased formalin-induced nociception, as verified by the inhibition of the first and second phase of the formalin test. At 30 mg/kg, EOPPgfl also decreased thermally stimulated nociception. Nociception may be related to inflammatory and antiedematogenic activity and at doses ranging 10–100 mg/kg, EOPPgfl blocked dextran- and carrageenan-induced edema. The results demonstrated that EOPPgfl presented, at doses approximately 100 times smaller than LD₅₀, an antinociceptive effect that probably was due to anti-inflammatory activities.

LASSBio-1586, an N-acylhydrazone derivative, attenuates nociceptive behavior and the inflammatory response in mice

Pain and inflammation are complex clinical conditions that are present in a wide variety of disorders. Most drugs used to treat pain and inflammation have potential side effects, which makes it necessary to search for new sources of bioactive molecules. In this paper, we describe the ability of LASSBio-1586, an N-acylhydrazone derivative, to attenuate nociceptive behavior and the inflammatory response in mice. Antinociceptive activity was evaluated through acetic acid-induced writhing and formalin-induced nociception tests. In these experimental models, LASSBio-1586 significantly (p<0.05) reduced nociceptive behavior. Several methods of acute and chronic inflammation induced by different chemical (carrageenan, histamine, croton oil, arachidonic acid) and physical (cotton pellet) agents were used to evaluate the anti-inflammatory effect of LASSBio-1586. LASSBio-1586 exhibited potent anti-inflammatory activity in all tests (p<0.05). Study of the mechanism of action demonstrated the possible involvement of the nitrergic, serotonergic and histamine signaling pathways. In addition, a molecular docking study was performed, indicating that LASSBio-1586 is able to block the COX-2 enzyme, reducing arachidonic acid metabolism and consequently decreasing the production of prostaglandins, which are important inflammatory mediators. In summary, LASSBio-1586 exhibited relevant antinociceptive and anti-inflammatory potential and acted on several targets, making it a candidate for a new multi-target oral anti-inflammatory drug.