Anti-inflammatory action of ethanolic extract and clerodane diterpenes from Casearia sylvestris

Promising Effects of Casearins in Tumor-Bearing Mice and Antinociceptive Action against Oncologic Pain: Molecular Docking and In Vivo Findings

Safer analgesic drugs remain a hard challenge because of cardiovascular and/or gastrointestinal toxicity, mainly. So, this study evaluated in vivo the antiproliferative actions of a fraction with casearins (FC) from Casearia sylvestris leaves against human colorectal carcinomas and antihyperalgesic effects on inflammatory- or opiate-based pain relief and oncologic pain in Sarcoma 180 (S180)-bearing mice. Moreover, docking investigations evaluated the binding among Casearin X and NMDA(N-methyl-D-aspartate)-type glutamate receptors. HCT-116 colorectal carcinoma-xenografted mice were treated with FC for 15 days. Antinociceptive assays included chemically induced algesia and investigated mechanisms by pharmacological blockade. Intraplantar region S180-bearing animals received a single dose of FC and were examined for mechanical allodynia and behavior alterations. AutoDock Vina determined molecular interactions among Cas X and NMDA receptor subunits. FC reduced tumor growth at i.p. (5 and 10 mg/kg) and oral (25 mg/kg/day) doses (31.12-39.27%). FC reduced abdominal pain, as confirmed by formalin and glutamate protocols, whose antinociception activity was blocked by naloxone and L-NAME (neurogenic phase) and naloxone, atropine, and flumazenil (inflammatory phase). Meanwhile, glibenclamide potentiated the FC analgesic effects. FC increased the paw withdrawal threshold without producing changes in exploratory parameters or motor coordination. Cas X generated a more stable complex with active sites of the NMDA receptor GluN2B subunits. FC is a promising antitumor agent against colorectal carcinomas, has peripheral analgesic effects by desensitizing secondary afferent neurons, and inhibits glutamate release from presynaptic neurons and/or their action on cognate receptors. These findings emphasize the use of clerodane diterpenes against cancer-related pain conditions.

Metabolism Characterization and Chemical and Plasma Stability of Casearin B and Caseargrewiin F

Oral preparations of Casearia sylvestris (guacatonga) are used as antacid, analgesic, anti-inflammatory, and antiulcerogenic medicines. The clerodane diterpenes casearin B and caseargrewiin F are major active compounds in vitro and in vivo. The oral bioavailability and metabolism of casearin B and caseargrewiin F were not previously investigated. We aimed to assess the stability of casearin B and caseargrewiin F in physiological conditions and their metabolism in human liver microsomes. The compounds were identified by UHPLC-QTOF-MS/MS and quantified by validated LC-MS methods. The stability of casearin B and caseargrewiin F in physiological conditions was assessed in vitro. Both diterpenes showed a fast degradation (p < 0.05) in simulated gastric fluid. Their metabolism was not mediated by cytochrome P-450 enzymes, but the depletion was inhibited by the esterase inhibitor NaF. Both diterpenes and their dialdehydes showed a octanol/water partition coefficient in the range of 3.6 to 4.0, suggesting high permeability. Metabolism kinetic data were fitted to the Michaelis-Menten profile with KM values of 61.4 and 66.4 µM and Vmax values of 327 and 648 nmol/min/mg of protein for casearin B and caseargrewiin F, respectively. Metabolism parameters in human liver microsomes were extrapolated to predict human hepatic clearance, and suggest that caseargrewiin F and casearin B have a high hepatic extraction ratio. In conclusion, our data suggest that caseargrewiin F and casearin B present low oral bioavailability due to extensive gastric degradation and high hepatic extraction.

Gastroprotective and gastric healing effects of the aqueous extract of Casearia sylvestris in rodents: Ultrasound, histological and biochemical analyzes

ETHNOPHARMACOLOGICAL IMPORTANCE

Casearia sylvestris Sw. (Salicaceae) is a native plant from the Americas, where it is also known as "guaçatonga" or "erva-de-bugre." Although its leaves have been commonly used to treat inflammation and gastrointestinal disorders in South America, the antiulcer effects of an aqueous extract from this medicinal plant, similar to popular use, have not to be investigated yet.

AIM OF THE STUDY

This study evaluated the hypothesis that the aqueous extract a of C. sylvestris (AEC) prevents the gastric ulcers and accelerates the healing of ulcers already installed, by assessing ultrasound imaging, histological and biochemical analyses.

MATERIALS AND METHODS

Rats (females) were treated with AEC (3, 30 or 300 mg/kg) prior to the ethanol or piroxicam-induced gastric ulcers. The healing effect of AEC (300 mg/kg) was examined in 80% acetic acid-induced ulcer in rats, whereas the quality of healing was evaluated in recurrent 10% acetic acid-induced ulcer in mice with recurrence induced by interleukin 1β. To assess the responses of the lesions, in addition to the classical methods used to analyze gastroprotection (ex vivo), we also measured the gastric wall thickness (in vivo) using ultrasonography. After euthanasia, the extent of ulcer was determined and the levels of reduced glutathione (GSH), lipid hydroperoxides (LOOH), nitrate, and the activities of myeloperoxidase (MPO), N-acetyl-β-D-glycosaminidase (NAG), superoxide dismutase (SOD), and glutathione S-transferase (GST) were measured. The antisecretory activity of AEC was also examined based on pylorus ligated rats. Furthermore, gastric tissue samples were analyzed histologically, and phytochemical analyses of the C. sylvestris extract were parallelly performed.

RESULTS

The AEC (30 or 300 mg/kg) prevented ulcers in the ethanol- and piroxicam-induced acute. Moreover, the AEC at a dose of 300 mg/kg also accelerated the gastric healing of acetic acid-induced ulcer in rats by 48% and the ultrasonography records shown a decrease in the wall thickness and the extent of edema of ulcerous lesions promoted by the extract. The gastric healing effect of AEC was also accompanied by reduced MPO and NAG activities at acetic acid-induced ulcer in rats; as well as was by the reduction in the nitrate and LOOH levels, the increase in mucin and SOD activity, and by a partial recovery of GSH levels. The AEC (300 mg/kg) minimized the ulcer recurrence in mice exposed to IL-1β, but the extract administration did not change pH or peptic activity of gastric juice in pylorus ligated rats.

CONCLUSION

The results of this study provide convincing evidence for the therapeutic efficacy of C. sylvestris with respect to gastroprotection and indicate that ultrasound examination would be a potentially promising approach for evaluating gastroprotective effects in vivo. Collectively, our findings indicate that the gastric the gastroprotective and healing effects of aqueous extract C. sylvestris involve a reduction in acid secretion, promotion of the antioxidant system, reductions in the migration of neutrophils and mast cells, with a consequent lower inflammatory response, and the preservation of mucin.

Phytochemistry and Biological Activity of Medicinal Plants in Wound Healing: An Overview of Current Research

Wound healing is a complicated process, and the effective management of wounds is a major challenge. Natural herbal remedies have now become fundamental for the management of skin disorders and the treatment of skin infections due to the side effects of modern medicine and lower price for herbal products. The aim of the present study is to summarize the most recent in vitro, in vivo, and clinical studies on major herbal preparations, their phytochemical constituents, and new formulations for wound management. Research reveals that several herbal medicaments have marked activity in the management of wounds and that this activity is ascribed to flavonoids, alkaloids, saponins, and phenolic compounds. These phytochemicals can act at different stages of the process by means of various mechanisms, including anti-inflammatory, antimicrobial, antioxidant, collagen synthesis stimulating, cell proliferation, and angiogenic effects. The application of natural compounds using nanotechnology systems may provide significant improvement in the efficacy of wound treatments. Increasing the clinical use of these therapies would require safety assessment in clinical trials.

In vitro schistosomicidal activities of the leaf extracts from Casearia sylvestris varieties

Schistosomiasis, a tropical disease caused by flatworms, may affect the liver, spleen, bladder, and intestine. Casearia sylvestris Swartz, a medicinal plant, displays antiprotozoal, antimicrobial, antifungal, and antiulcer activities. We have evaluated the in vitro schistosomicidal activity of two C. sylvestris varieties against Schistosoma mansoni adult worms at concentrations between 12.5 and 200 μg/mL of and var. lingua . At 100 and 200 μg/mL, the ethanolic C. sylvestris var. sylvestris leaf extract enriched in casearin-like diterpenes eliminated 100% of the parasites after incubation for 72 h and 48 h, respectively, whilst the same extract at 200 μg/mL eliminated 96%, 100%, and 100% of the parasites after incubation for 24, 48, and 72 h, respectively. On the other hand, the hydroalcoholic C. sylvestris var. lingua leaf extract at 200 μg/mL eliminated 60.4 and 66.7% of the parasites after incubation for 48 and 72 h, respectively. The presence of casearin-like diterpenes and glycosylated flavonoids was confirmed based on chromatographic techniques and mass spectrometry data.

Neo-clerodane diterpenic influence in the antinociceptive and anti-inflammatory properties of Salvia circinnata Cav

ETHNOPHARMACOLOGICAL RELEVANCE

Mexico is considered an ancestral center of diversity of Salvia species, however many of them lack scientific information. Salvia circinnata Cav. (syn. Salvia amarissima Ortega) is an endemic species used in traditional medicine to treat disorders attributed to a cold state like anxiety in the central nervous system, as well as gastrointestinal ailments and pain relief.

AIM OF THE STUDY

To give preclinical evidence about the pharmacological properties of this species by investigating its antinociceptive and anti-inflammatory effects, the chemical nature of at least one metabolite, and a possible mechanism of action and adverse effects, using different experimental models of pain.

MATERIAL AND METHODS

Different crude extracts of Salvia circinnata Cav. aerial parts were prepared using increasing polarity and evaluated in the formalin test in mice. This screening allowed to select and evaluate an ethyl acetate extract (EtOAc), as the most bioactive extract, and a metabolite. Antinociceptive and anti-inflammatory activities were confirmed using the plantar test and carrageenan-induced edema. The antinociceptive effects of the extracts were compared to that observed with morphine (1 mg/kg), tramadol (20 mg/kg) or indomethacin (20 mg/kg) as reference drugs. Participation of opioids and TRPV1 receptors was investigated, as well as acute toxicity and adverse effects of sedation and gastric damage.

RESULTS

EtOAc (0.1-10 mg/kg) of S. circinnata Cav. showed a dose-dependent and significant antinociceptive activity, associated in part with the presence of a neo-clerodane glycoside amarisolide A (0.01-1 mg/kg), in the neurogenic and inflammatory phases of the formalin test. Central action of both treatments was corroborated in the plantar test, whereas anti-inflammatory effects were confirmed with the extract (1 and 10 mg/kg) and amarisolide A (1 mg/kg) in the carrageenan-induced edema test. An opioid mechanism in both treatments, and the TRPV1 receptor modulation in the extract were involved. No acute toxicity and adverse effects were noticed with the extract and pure compound in comparison to the reference drugs.

CONCLUSION

These results provide preclinical evidence of the ethnopharmacological antinociceptive S. circinnata Cav. properties, in which the neo-clerodane diterpene glycoside amarisolide A was partially responsible involving the participation of the opioid receptors, while TRPV1 receptor modulation was implicated in the anti-inflammatory activity may be because of the presence of other constituents. This information supports the use of this species in folk medicine for pain therapy.

The drug likeness analysis of anti-inflammatory clerodane diterpenoids

Inflammation is an active defense response of the body against external stimuli. Long term low-grade inflammation has been considered as a deteriorated factor for aging, cancer, neurodegeneration and metabolic disorders. The clinically used glucocorticoids and non-steroidal anti-inflammatory drugs are not suitable for chronic inflammation. Therefore, it's urgent to discover and develop new effective and safe drugs to attenuate inflammation. Clerodane diterpenoids, a class of bicyclic diterpenoids, are widely distributed in plants of the Labiatae, Euphorbiaceae and Verbenaceae families, as well as fungi, bacteria, and marine sponges. Dozens of anti-inflammatory clerodane diterpenoids have been identified on different assays, both in vitro and in vivo. In the current review, the up-to-date research progresses of anti-inflammatory clerodane diterpenoids were summarized, and their druglikeness was analyzed, which provided the possibility for further development of anti-inflammatory drugs.

Fragmentation study of clerodane diterpenes from Casearia species by tandem mass spectrometry (quadrupole time-of-flight and ion trap)

RATIONALE

Clerodane-type diterpenes from Casearia species show important pharmacological activites such as antitumor, antimicrobial and anti-inflamatory. There are several mass spectrometry (MS)-based methods for identification of diterpenes; however, there is still a lack of MS procedures capable of providing characteristic fragmentation pathways for a rapid and unambiguous elucidation of casearin-like compounds.

METHODS

Casearin-like compounds were investigated by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The fragmentation studies were carried out by tandem mass spectrometry in space (quadrupole time-of-flight (QTOF)) using different collision energies and also by tandem mass spectrometry in time (QIT) by selective isolation of product ions.

RESULTS

Casearin-like compounds presented a predominance of sodium- and potassium-cationized precursor ions. Both QIT and QTOF techniques provided sequential neutral losses of esters related to the R₁ to R₅ substituents linked to the nucleus of the clerodane diterpenes. The fragmentation pathway is initiated with a cleavage of the ester moieties R₂ followed by the elimination of the ester groups R₃ , both losing neutral carboxylic acids. Using QIT, it was also possible to observe the cleavage of the ester groups R₁ or R₅ by MS⁴ experiments.

CONCLUSIONS

Through a rational analysis of the fragmentation mechanisms of Casearia diterpenes it was possible to suggest an annotation strategy based on the sequential cleavages of the ester groups related to the R₂ , R₃ and R₅ substituents. These results will assist studies of the dereplication and metabolomics involving casearin-like compounds present in complex extracts of Casearia species.

Chemical Constituents and Pharmacological Activities of Family Flacourtiaceae: A Class of Important Phytomedicine

Flacourtiaceae plants are widely used as folk medicines in traditional medicine systems for its chemical diversity and pharmacological activities. In many different areas, Flacourtiaceae plants are used as traditional medicines for the treatment of ulcers, malaria, rheumatism. The Flacourtiaceae plants contain a very plentiful chemical composition, and phytochemical studies show that the Flacourtiaceae plants contained terpenoids, aromatic glycosides, flavnoids, phenylpropanoids, alkaloids, fatty hydrocarbon, and other compounds. In pharmacological studies, various extract and isolated individual compounds exhibited antitumor, anti-oxidation, and anti-inflammatory activities. In this review, the literature data on the chemical constituents and pharmacological investigations of the Flacourtiaceae plants are summarized, to provide information about a more comprehensive chemical composition and detailed pharmacological activities of Flacourtiaceae plants, with a view of further development of clinical medication. However, research on quantitative analysis, toxicity, and drug safety in vitro and in vivo is still insufficient, and further research is required.