Brígido Heliton Patrick Cordovil, Varela Everton Luiz Pompeu, Quadros Gomes Antônio Rafael, Neves Cruz Jorddy, Correa-Barbosa Juliana, Siqueira José Edson de Sousa, Chagas Cristian Kallahan Silva, Marinho Andrey Moacir do Rosário, Almeida Carneiro Liliane, Coelho-Ferreira Márlia Regina, Percário Sandro, Dolabela Maria Fâni
Postgraduate Pharmaceutical Innovation Program, Institute of Health Sciences, Federal University of Pará, Belém, Brazil.
Post-Graduate Program in Biodiversity and Biotechnology, Belém, Brazil.
Front Chem. 2024 Oct 31;12:1492770. doi: 10.3389/fchem.2024.1492770. eCollection 2024.
The lack of vaccines shows the need for alternative leishmaniasis treatments. study previously demonstrated the leishmanicidal activity of extracts. This study describes for the first time, the antileishmanial activity of extracts in infected Balb/c mice and its immunomodulatory effect. The extract (EE) was obtained by maceration of the peel powder with ethanol, which was fractionated by acid-base partition, originating the alkaloid (FA) and neutral (FN) fractions. EE and FA were analyzed using mass spectroscopy. Daily intragastric treatment was performed with EE and FA, at doses of 200 mg/kg and 400 mg/kg, in Balb/c mice with 28 days of infection by . A thickness gauge was used to assess the progression of the lesion and the MTT method to determine the parasite load in the spleen. The quantification of IL-10 and IFN-γ was performed by ELISA. Analysis of the mass spectrum of EE indicated the presence of the alkaloids corynantheol and yohimbine, while in FA the alkaloid dihydrocorynantheol was identified. To elucidate the mode of interaction of these alkaloids with the TR protein, molecular target of antileishmanial drugs, we used molecular modeling approaches such as docking, molecular dynamics simulations and free energy affinity. Treatment with EE for 28 days at the highest dose tested, significantly reduced the size of the lesion. EE and FA after 28 days of treatment showed dose-dependent antileishmanial activity, which reduced the parasite load in the spleen of infected mice by 42.5% and 22.1%, respectively. Both EE and FA presented immunomodulatory effect, as they decreased IL-10 expression and increased IFN-y levels. The effectiveness of in the treatment of cutaneous leishmaniasis was proven in this study. The results obtained demonstrated that the compounds are capable of interacting with the catalytic residues of the TR. The affinity energy results demonstrated that the complexes formed are favorable for enzymatic inhibition. The alkaloids present in the plant have demonstrated not only antileishmanial activity, but also the ability to modulate the host's immune response. These promising results open perspectives for developing more effective and comprehensive treatments against cutaneous leishmaniasis.
疫苗的缺乏表明需要替代的利什曼病治疗方法。先前的一项研究证明了提取物的杀利什曼活性。本研究首次描述了提取物在感染的Balb/c小鼠中的抗利什曼活性及其免疫调节作用。提取物（EE）通过用乙醇浸渍果皮粉末获得，经酸碱分配进行分级分离，得到生物碱（FA）和中性（FN）馏分。使用质谱对EE和FA进行分析。对感染28天的Balb/c小鼠，分别以200mg/kg和400mg/kg的剂量用EE和FA进行每日胃内治疗。使用厚度计评估病变进展，采用MTT法测定脾脏中的寄生虫载量。通过ELISA对IL-10和IFN-γ进行定量分析。EE的质谱分析表明存在生物碱可待因醇和育亨宾，而在FA中鉴定出生物碱二氢可待因醇。为了阐明这些生物碱与抗利什曼药物的分子靶点TR蛋白的相互作用模式，我们使用了分子对接、分子动力学模拟和自由能亲和力等分子建模方法。在测试的最高剂量下用EE治疗28天，显著减小了病变大小。治疗28天后，EE和FA均表现出剂量依赖性的抗利什曼活性，分别使感染小鼠脾脏中的寄生虫载量降低了42.5%和22.1%。EE和FA均呈现免疫调节作用，因为它们降低了IL-10表达并提高了IFN-γ水平。本研究证明了其在治疗皮肤利什曼病方面的有效性。所获得的结果表明这些化合物能够与TR的催化残基相互作用。亲和力能量结果表明形成的复合物有利于酶抑制。植物中存在的生物碱不仅表现出抗利什曼活性，还具有调节宿主免疫反应的能力。这些有前景的结果为开发更有效和全面的皮肤利什曼病治疗方法开辟了前景。
