NMR spectroscopy spotlighting immunogenicity induced by COVID-19 vaccination to mitigate future health concerns.

In this review, the disease and immunogenicity affected by COVID-19 vaccination at the metabolic level are described considering the use of nuclear magnetic resonance (NMR) spectroscopy for the analysis of different biological samples. Consistently, we explain how different biomarkers can be examined in the saliva, blood plasma/serum, bronchoalveolar-lavage fluid (BALF), semen, feces, urine, cerebrospinal fluid (CSF) and breast milk. For example, the proposed approach for the given samples can allow one to detect molecular biomarkers that can be relevant to disease and/or vaccine interference in a system metabolome. The analysis of the given biomaterials by NMR often produces complex chemical data which can be elucidated by multivariate statistical tools, such as PCA and PLS-DA/OPLS-DA methods. Moreover, this approach may aid to improve strategies that can be helpful in disease control and treatment management in the future.

Evaluation of leishmanicidal and trypanocidal activities of phenolic compounds from Calea uniflora Less.

The phytochemical study of Calea uniflora led to the isolation of nine phenolic compounds identified as noreugenin (1), ethyl caffeate (2), a mixture of butein (3) + orobol (4), α-hydroxy-butein (5), caffeic acid (6), butein 4'-O-glucopyranosyl (7), quercetin 3-O-glucopyranosyl (8) and 3,5-di-O-caffeoylquinic acid (9). The chemical identity of the isolates was established on the basis of NMR and physical data. The chemical shifts of 5 and 7 have been reassigned and all the isolates were tested against Leishmania amazonensis and Trypanosoma cruzi amastigotes. None of the metabolites showed promising leishmanicidal activity. However, 2 and the mixture of 3 and 4 demonstrated interesting trypanocidal effect with IC50 values of 18.27 and 26.53 µM, respectively. Besides, these compounds did not present cytotoxic effect towards THP-1 cells, and compound 2 was 3.5-fold more selective than the mixture of 3+4.

Evaluation of the cytotoxic activity of some Brazilian medicinal plants.

Plants are promising sources of new bioactive compounds. The aim of this study was to investigate the cytotoxic potential of nine plants found in Brazil. The species studied were: Annona pickelii Diels (Annonaceae), Annona salzmannii A. DC. (Annonaceae), Guatteria blepharophylla Mart. (Annonaceae), Guatteria hispida (R. E. Fr.) Erkens & Maas (Annonaceae), Hancornia speciosa Gomes (Apocynaceae), Jatropha curcas L. (Euphorbiaceae), Kielmeyera rugosa Choisy (Clusiaceae), Lippia gracilis Schauer (Verbenaceae), and Hyptis calida Mart. Ex Benth (Lamiaceae). Different types of extractions from several parts of plants resulted in 43 extracts. Their cytotoxicity was tested against HCT-8 (colon carcinoma), MDA-MB-435 (melanoma), SF-295 (glioblastoma), and HL-60 (promielocitic leukemia) human tumor cell lines, using the thiazolyl blue test (MTT) assay. The active extracts were those obtained from G. blepharophylla, G. hispida, J. curcas, K. rugosa, and L. gracilis. In addition, seven compounds isolated from the active extracts were tested; among them, ß-pinene found in G. hispida and one coumarin isolated from K. rugora showed weak cytotoxic activity. In summary, this manuscript contributes to the understanding of the potentialities of Brazilian plants as sources of new anticancer drugs.

Beneficial effects of the ethanol extract of Caesalpinia pyramidalis on the inflammatory response and abdominal hyperalgesia in rats with acute pancreatitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Caesalpinia pyramidalis Tul. (Fabaceae) is a plant found in the Northeast of Brazil that is popularly used to treat inflammation. Acute pancreatitis (AP) is an inflammatory disease for which abdominal pain is a relevant symptom. As there is no specific therapy for AP, we investigated the effect of the ethanol extract from the inner bark of C. pyramidalis (EECp) on the AP induced by common bile duct obstruction (CBDO) in rats. MATERIAL AND METHODS: AP was induced in male Wistar rats (200-250 g, n=6-8) through laparotomy and subsequent CBDO. Animals were euthanized after 6 (G6h) or 24 h (G24h) of induction. In the G6h protocol, animals were pretreated with EECp (100-400 mg/kg, p.o.) or vehicle (Tween 80; 0.2%) 1h before CBDO or sham surgery. For the G24h protocol, rats were pretreated with EECp (400mg/kg, 1h before CBDO or 1 h before and 12 h after CBDO) or vehicle. The following parameters were measured: inflammatory/oxidative (myeloperoxidase activity and malondialdehyde formation in the pancreas and lung, leukocyte counts in the blood and serum nitrate/nitrite), enzymatic (serum amylase and lipase levels) and nociceptive (abdominal hyperalgesia). RESULTS: Induction of AP by CBDO significantly increased all the parameters evaluated in both G6h and G24h protocols when compared with the respective sham group. In the G6h protocol, the EECp pretreatment (400 mg/kg) significantly reduced all these parameters, besides completely inhibiting abdominal hyperalgesia. The same profile of reduction was observed from two administrations of EECp in the G24h protocol, while one single dose of EECp was able to significantly reduce pancreatic MDA, serum lipase levels, leukocyte counts in the blood and abdominal hyperalgesia without affecting the other parameters in the G24h protocol. Furthermore, rutin was found in the EECp. CONCLUSIONS: Our results demonstrated that EECp decreases inflammation, lipoperoxidation and hyperalgesia in CBDO-induced AP, making it of interest in future approaches to treat this condition.

Phytochemical characterization and antinociceptive effect of Lippia gracilis Schauer.

Lippia gracilis Schauer is an aromatic plant widely found in Northeastern Brazil. The leaf infusions or decoctions and alcoholic macerate are used for some inflammatory diseases and headache. This paper reports the isolation of naringenin by semi-preparative liquid chromatography from the methanolic extract of L. gracilis (ELg) and the evaluation of the analgesic and anti-inflammatory activities of this extract by measuring nociception through acetic acid, formalin, and hot-plate tests in carrageenan-induced inflammation in mice. Following oral administration, ELg (100, 200, and 400 mg/kg) significantly reduced the number of writhes in the writhing test and the time of paw licks in both phases of the formalin test when compared to the control group animals. Mice treated with ELg did not exhibit any behavioral alteration during the hot plate and rota-rod tests, suggesting non-participation of the supraspinal components in the modulation of pain by ELg and no motor abnormality. The oral administration of 400 mg/kg of ELg produced an anti-inflammatory effect on peritonitis induced by carrageenan. These effects can be associated with a decrease of inflammatory mediator synthesis by compounds of ELg, such as naringenin, which has anti-inflammatory action as already described.