Toxicological evaluation of ethanolic extract of leaves from Doliocarpus dentatus in Swiss mice

Doliocarpus dentatus (Dilleniaceae) has been used in folk medicine to treat inflammation and pain; however, studies evaluating its toxicity potential, as well as its effects on anxiety and depression, are scarce. This study investigated the toxicological profile of an ethanolic extract from leaves of D. dentatus (EEDd), and its effects on anxiety and depression models in mice. Male and female mice received either a single dose (500, 1000 or 2000 mg/kg) or repeated doses (75, 150 or 300 mg/kg) of EEDd by oral gavage. During the subacute toxicity assay, behavioral tests were performed on days 4, 14, 21 and 28. No evidence of toxicity was observed in the animals in both acute and subacute tests. However, males treated with the highest dose presented a reduction in the absolute weight of the kidney, an elevation in the AST levels, in addition to an alteration in the urea levels. The treatment did not affect other biochemical parameters, and did not induce any depressive-like behavior. EEDd exhibited low toxicity after single and repeated exposures. Since some analyzed parameters were compromised, further toxicity studies should be carried out.

Anti-inflammatory activity and chemical composition of aqueous extract and essential oil from leaves of Ocimum selloi Benth

ETHNOPHARMACOLOGICAL RELEVANCE

The population uses the aqueous extract as tea from leaves of Ocimum selloi Benth. (alfavaca) for pain and inflammation issues. This study is motivated by a lack of data about inflammation properties of O. selloi.

AIM OF THE STUDY

This study investigated the chemical composition and anti-inflammatory activity, in mice models, of the aqueous extract (OSAE) and essential oil (OSEO) obtained from leaves of O. selloi.

MATERIALS AND METHODS

The antioxidant activity and total phenolic content were evaluated for samples, although chemical composition was obtained by U-HPLC-DAD-ESI-MS for OSAE and GC-MS for OSEO. OSAE and OSEO were tested orally at doses of 30, 100 and 300 mg/kg at the carrageenan-induced pleurisy and paw edema, also mechanical hyperalgesia, in mice.

RESULTS

Four glycosylated flavonoids and one organic acid were identified in OSAE, and nine substances in OSEO, the two majoritarian are E-anethole and methyl chavicol. Oral treatments with OSAE and OSEO significantly inhibited the carrageenan-induced pleurisy in female Swiss mice, besides OSAE and OSEO significantly prevented paw edema (after 1, 2, and 4 h), mechanical hyperalgesia (after 3 and 4 h), and cold hyperalgesia 3 h after carrageenan model in male Swiss mice. The dose of 300 mg/kg of OSEO reduced cold hyperalgesia 4 h after carrageenan.

CONCLUSION

The results evidenced the anti-inflammatory, anti-edematogenic, anti-hyperalgesic, and anti-nociceptive potentials of both materials obtained from leaves of O. selloi, mainly OSAE, supporting the popular use of this species.

Polymerase chain reaction using conjunctival swab samples for detecting Leishmania DNA in dogs

The dog is the main domestic reservoir of Leishmania and font of infection for the vector, constituting an important host for the transmission of the parasite to humans. Non-invasive collection of swab samples for leishmaniasis diagnosis has been a promising alternative. This study analyzed the positivity of polymerase chain reaction (PCR) for the diagnosis of canine leishmaniasis in conjunctiva samples. DNA extraction was performed using SDS 20% and PCR was performed using 13A/13B primers that amplify 120-bp of Leishmania kDNA. Of the 77 dogs analyzed, 50 (64.93%) had ocular changes: 25 (32.47%) dogs had periocular lesion, 41 (53.25%) dogs had purulent eye discharge, and 17 (22.08%) dogs had both signals. PCR was positive in 35 dogs (45.45%), and there was no significant difference between dogs with and without ocular signals (p=0.4074). PCR positivity was significant higher in dogs without periocular injury (p=0.0018). Conjunctive PCR, a less invasive, fast, and painless collection technique, is indicated to complement the diagnosis, especially in dogs without periocular injury, independent of the presence of purulent eye discharge.

Aqueous extract from leaves of Doliocarpus dentatus (Aubl.) Standl. relieves pain without genotoxicity activity

ETHNOPHARMACOLOGICAL RELEVANCE

In the State of Mato Grosso do Sul, the watery sap of Doliocarpus dentatus is used to alleviate thirst, and the leaves of this species are used to relieve pain and swelling associated with inflammatory processes.

AIM OF THE STUDY

This study aimed to analyze the compounds of the leaves from the aqueous extract of D. dentatus (EADd) and evaluate its toxicogenetic and pain relief effects in animal models.

MATERIALS AND METHODS

Compounds were identified in EADd by UHPLC-HRMS (Ultra high-performance liquid chromatography coupled to high resolution mass spectrometry). The oral dose of 17 mg/kg EADd, calculated according to ethnopharmacological uses, and doses between 30 and 300 mg/kg were used to test Swiss mice in formalin- and acetic acid-induced models of pain and behavior. EADd (100-2000 mg/kg) was assayed in mice by comet, micronucleus, and phagocytosis tests and by peripheral leukocyte counts.

RESULTS

Phenolic compounds and flavonoids as well as trigonelline and isoquercetin were identified in EADd. All oral doses of EADd exhibited antinociceptive activity, as indicated by a decrease in pain in both phases, a decrease in cold hypersensitivity induced by formalin, and a decrease in abdominal contortions induced by acetic acid. EADd did not alter the exploratory, motor or motivational activities of the animals. The comet and micronucleus tests indicated that EADd was not genotoxic and did not change the phagocytic activity or peripheral leukocyte count.

CONCLUSIONS

These results demonstrate that EADd could act as an antinociceptive agent that does not present genotoxicity. This study should contribute to justifying, in part, the popular use of D. dentatus in pain management, ensuring its safe use.

Evaluation of the toxicity and anti-inflammatory activities of the infusion of leaves of Campomanesia guazumifolia (Cambess.) O. Berg

ETHNOPHARMACOLOGICAL RELEVANCE

Some species of Campomanesia are used in the folk medicine due to anti-inflammatory, anti-diarrheal, anti-diabetes and hypercholesterolemic. However studies with Campomanesia guazumifolia (Cambess.) O. Berg. are scarce.

AIM OF THE STUDY

This study investigated the anti-inflammatory activity and toxicological profile of infusion obtained from leaves of Campomanesia guazumifolia in mice.

MATERIALS AND METHODS

Leaves infusion of C. guazumifolia was obtained in the proportion of 20 g/L (leaves/water) at 95-100 °C for 10 min in an enclosed container. The acute toxicity of the leaves infusion of C. guazumifolia lyophilized (ICG) was assessed by oral administration to female mice at doses of 500, 1000, 2000, and 5000 mg/kg, and the general behavior and toxic symptoms were observed for 14 days. In the subacute toxicity model, female mice were treated orally with the ICG (250, 500, and 1000 mg/kg) during 28 days, and biochemical, toxic signs and the estrous cycle were evaluated. The anti-inflammatory activity of the ICG (70, 300 and 700 mg/kg) was analyzed using carrageenan-induced pleurisy and inflammatory paw (mechanical and thermal hyperalgesia).

RESULTS

Three flavonoids glycosylated and a cyclohexanecarboxylic acid were identified in the ICG: quercetin pentose, quercetin deoxyhexoside, myricetin deoxyhexoside and quinic acid. No clinical signs of acute toxicity were observed, suggesting that the LD₅₀ (Lethal Dose) is above 5000 mg/kg. Subacute exposure of mice to the ICG did not change significantly the hematological and biochemical parameters as well as histology of organs. The ICG increased the duration of estrous cycle in all phases, showing anti-inflammatory potential by decreasing leukocyte migration, extravasation protein in the pleural cavity and antiedematogenic activity. The ICG treatment at a dose of 700 mg/kg decreased the mechanical hyperalgesia, while at doses of 300 mg/kg and 700 mg/kg, decreased the sensitivity to the cold.

CONCLUSION

The results evidenced the anti-inflammatory potential with low toxicity of infusion of the leaves of C. guazumifolia, supporting the popular use of this species.

Anti-inflammatory and toxicological evaluation of essential oil from Piper glabratum leaves

ETHNOPHARMACOLOGICAL RELEVANCE

Although some of the species of the genus Piper exhibit interesting biological properties, studies on Piper glabratum Kunth are very limited.

AIM OF THE STUDY

This study investigated the anti-inflammatory activity and the toxicological profile of the essential oil from P. glabratum leaves (OEPG) in mice.

MATERIALS AND METHODS

The acute toxicity of OEPG was evaluated by oral administration to female mice as single doses of 500, 1000, 2000 or 5000mg/kg/body weight. In the subacute toxicity test, the females received 500 or 1000mg/kg/body weight of OEPG for 28 days. The anti-inflammatory potential of OEPG was evaluated using four models including pleurisy, edema, mechanical hyperalgesia and cold allodynia models in mouse paws.

RESULTS

No clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD₅₀ is greater than 5000mg/kg. The subacute exposure to OEPG produced no significant changes in the hematological or biochemical parameters. Similarly, the histology of the organs and the estrus cycle displayed no marked alterations. OEPG exhibited anti-inflammatory activity as indicated by inhibition of the leukocyte migration (100, 300, 700mg/kg) and the protein extravasation into the pleural exudates (700mg/kg). After intraplantar injection of carrageenan, it was observed that the 700mg/kg dose of OEPG reduced edema formation and decreased the sensitivity to mechanical stimulation and cold.

CONCLUSIONS

These results demonstrate the anti-inflammatory potential of the essential oil of P. glabratum leaves in the absence of toxicity in female mice.