Casearia sylvestris var. lingua (Càmbess.) Eichler leaves aqueous extract improves colon inflammation through mucogenic, antioxidant and anti-inflammatory actions in TNBS- induced IBD rats

ETHNOPHARMACOLOGICAL RELEVANCE

Casearia sylvestris var. lingua (Cambess.) Eichler, a member of the Salicaceae family, holds a prominent place in traditional medicine across various cultures due to its versatile therapeutic properties. Historically, indigenous communities have utilized different parts of the plant, including leaves, bark, and roots, to address a wide array of health conditions. Traditional uses of C. sylvestris var. lingua encompasses the treatment of gastrointestinal disorders, respiratory infections, wound healing, inflammation, and stomach ulcers. Pharmacological studies have demonstrated the plant's antimicrobial, anti-inflammatory, antioxidant, analgesic, gastroprotective, and immunomodulatory effects. This signifies the first scientific validation report for C. sylvestris var. lingua regarding its effectiveness against ulcerative colitis. The report aims to affirm the traditional use of this plant through pre-clinical experiments.

AIM OF THE RESEARCH

This work uses an aqueous extract from C. sylvestris var. lingua leaves (AECs) to evaluate the acute anti-ulcerative colitis efficacy in rat and HT-29 (human colorectal cancer cell line) models.

METHODS

To determine the secondary metabolites of AECs, liquid chromatography with a diode array detector (LC-DAD) study was carried out. 2,4,6-trinitrobenzenesulfonic acid (TNBS, 30 mg/0.25 mL EtOH 30% v/v) was used as an enema to cause acute colitis. Three days were spent giving the C. sylvestris var. lingua extract orally by gavage at dosages of 3, 30, and 300 mg/kg. The same route was used to deliver distilled water to the vehicle and naïve groups. After the animals were sacrificed on the fourth day, intestinal tissues were taken for histological examination and evaluation of biochemical tests such as those measuring superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), malondialdehyde (MDA), nitrite/nitrate, myeloperoxidase (MPO) activity. Additionally, interleukin 1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and interleukin 10 (IL-10), were conducted on the intestinal tissues. Additionally, an MTT assay was used to evaluate the effect of AECs on the viability of HT-29 cells. Additionally, a molecular docking study was carried out to compare some potential target proteins with identified chemicals found in AECs.

RESULTS

LC-DAD analysis identified five compounds (caffeic acid, ellagic acid, ferulic acid, gallic acid, and quercetin) in AECs. Pre-administration of AECs (3; 30; 300 mg/kg) and mesalazine (500 mg/kg) reduced macroscopic scores (55%, 47%, 45%, and 52%, p < 0.001) and ulcerated areas (70.3%, 70.5%, 57%, and 56%, p < 0.001), respectively. It also increased SOD, GSH, and CAT activities (p < 0.01), while decreasing MDA (p < 0.001), nitrite/nitrate (p < 0.05), and MPO (p < 0.001) activities compared to the colitis group. Concerning inflammatory markers, significant modulations were observed: AECs (3, 30, and 300 mg/kg) lowered levels of IL-1β and TNF-α (p < 0.001) and increased IL-10 levels (p < 0.001) compared to the colitis groups. The viability of HT-29 cells was suppressed by AECs with an IC50 of 195.90 ± 0.01 μg/mL (48 h). During the molecular docking analysis, quercetin, gallic acid, ferulic acid, caffeic acid, and ellagic acid demonstrated consistent binding affinities, forming stable interactions with the 3w3l (TLR8) and the 3ds6 (MAPK14) complexes.

CONCLUSION

These results imply that the intestinal mucogenic, anti-inflammatory, and antioxidant properties of the C. sylvestris var. lingua leaf extract may be involved in its therapeutic actions for ulcerative colitis. The results of the in silico study point to the possibility of quercetin and ellagic acid interacting with P38 and TLR8, respectively, in a beneficial way.

Comet assay and hormesis

The paper provides the first assessment of the occurrence of hormetic dose responses using the Comet assay, a genotoxic assay. Using a priori evaluative criteria based on the Hormetic Database on peer-reviewed comet assay experimental findings, numerous examples of hormetic dose responses were obtained. These responses occurred in a large and diverse range of cell types and for agents from a broad range of chemical classes. Limited attempts were made to estimate the frequency of hormesis within comet assay experimental studies using a priori entry and evaluative criteria, with results suggesting a frequency in the 40% range. These findings are important as they show that a wide range of genotoxic chemicals display evidence that is strongly suggestive of hormetic dose responses. These findings have significant implications for study design issues, including the number of doses selected, dose range and spacing. Likewise, the widespread occurrence of hormetic dose responses in this genotoxic assay has important risk assessment implications.

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.

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.

Toxicological findings about an anticancer fraction with casearins described by traditional and alternative techniques as support to the Brazilian Unified Health System (SUS)

ETHNOPHARMACOLOGICAL RELEVANCE

Extracts, essential oils and molecules from Casearia sylvestris have popularly shown pharmacological actions against chronic diseases, as anxiety, inflammation, cancer and dyslipidemia. In the context of antitumoral therapy, we investigated in vitro, ex vivo and in vivo toxicological changes induced by a Fraction with Casearins (FC) and its component Casearin X isolated from C. sylvestris on animal and vegetal cells, and upon invertebrates and mammals.

MATERIAL AND METHODS

Cytotoxicity was carried out using normal lines and absorbance and flow cytometry techniques, Artemia salina nauplii, Danio rerio embryos and meristematic cells from Allium cepa roots. Acute and 30 days-mice analysis were done by behavioral, hematological and histological investigations and DNA/chromosomal damages detected by alkaline Cometa and micronucleus assays.

RESULTS

FC was cytotoxic against lung and fibroblasts cells and caused DNA breaks, loss of integrity and mitochondrial depolarization on ex vivo human leukocytes. It revealed 24 h-LC₅₀ values of 48.8 and 36.7 μg/mL on A. salina nauplii and D. rerio embryos, reduced mitotic index of A. cepa roots, leading to cell cycle arrest at metaphase and anaphase and micronuclei. FC showed i.p. and oral LD₅₀ values of 80.9 and 267.1 mg/kg body weight. Subacute i.p. injections induced loss of weight, swelling of hepatocytes and tubules, tubular and glomerular hemorrhage, microvesicular steatosis, lung inflammatory infiltration, augment of GPT, decrease of albumin, alkaline phosphatase, glucose, erythrocytes, and lymphocytes, and neutrophilia (p > 0.05). FC-treated animals at 10 mg/kg/day i.p. caused micronuclei in bone marrow and DNA strand breaks in peripheral leukocytes.

CONCLUSIONS

This research postulated suggestive side effects after use of FC-related drugs, demonstrating FC as antiproliferative and genotoxic on mammal and meristematic cells, including human leukocytes, teratogenicity upon zebrafish embryos, myelosuppression, clastogenicity, and morphological and biochemical markers indicating liver as main target for FC-induced systemic toxicity.

In vitro and in vivo anti-Helicobacter pylori activity of Casearia sylvestris leaf derivatives

ETHNOPHARMACOLOGICAL RELEVANCE

The number of bacterial strains that are resistant to multiple conventional antimicrobial agents is increasing. In this context, natural products have been widely used as a strategy to treat diseases caused by bacteria. Infections by Helicobacter pylori have attracted attention because they are directly related to severe gastric medical conditions. Casearia sylvestris Swartz, popularly known as guaçatonga, is largely employed to treat gastric disorders in Brazilian folk medicine. This plant species has aroused much interest mainly because it displays anti-inflammatory activity and can act as an antiulcer agent.

AIM OF THE STUDY

To evaluate the in vitro and in vivo anti-H. pylori action of C. sylvestris leaf derivatives incorporated or not in a nanostructured drug delivery system.

MATERIALS AND METHODS

The essential oil (obtained by hydrodistillation) and ethanolic extract (obtained by maceration) were obtained from C. sylvestris leaves. The ethanolic extract was submitted to fractionation through solid phase extraction and column chromatography, to yield the ethanolic fractions. Hydrolyzed casearin J was achieved by submitting isolated casearin J to acid hydrolysis. The derivatives were chemically characterized by nuclear magnetic resonance (NMR), gas chromatography (GC), and gas chromatography-mass spectrometry (GC-MS) analyses. A nanostructured lipid system was used as drug delivery system. To assess the in vitro antibacterial activity of C. sylvestris leaf essential oil, ethanolic extract, and derivatives, microdilution, biofilm, and time-kill assays were performed against H. pylori ATCC 43504. Finally, the in vivo action was investigated by employing male Wistar rats experimentally infected with H. pylori.

RESULTS

Many C. sylvestris leaf derivatives presented significant in vitro activity against H. pylori. Among the derivatives, fraction 2 (F2) was the most effective. In vivo tests showed that both the ethanolic extract and F2 decreased the ulcerative lesion size, but only the ethanolic extract eradicated H. pylori from the gastric lesions. Incorporation of plant derivatives in nanostructured lipid system blunted the in vitro action, as demonstrated by the microdilution assay. However, this incorporation improved the ethanolic extract activity against biofilms.

CONCLUSION

C. sylvestris leaf derivatives are effective against H. pylori both in vitro and in vivo. According to phytochemical analyses, these derivatives are rich in terpenoids, which could be related to the anti-H. pylori action. Synergism could also underlie C. sylvestris efficacy judging from the fact that the sub-fractions and isolated compounds had lower activity than the extract. Incorporation in a nanostructured lipid system did not improve the activity of the compounds in our in vivo protocol.

Cardanol: toxicogenetic assessment and its effects when combined with cyclophosphamide

Cardanol is an effective antioxidant and is a compound with antimutagenic and antitumoral activity. Here, we evaluated the genotoxic and mutagenic potential of saturated side chain cardanol and its effects in combination with cyclophosphamide in preventing DNA damage, apoptosis, and immunomodulation. Swiss mice were treated with cardanol (2.5, 5 and 10 mg/kg) alone or in combination with cyclophosphamide (100 mg/kg). The results showed that cardanol is an effective chemopreventive compound, with damage reduction percentages that ranged from 18.9 to 31.76% in the comet assay and from 45 to 97% in the micronucleus assay. Moreover, cardanol has the ability to reduce the frequency of apoptosis induced by cyclophosphamide. The compound did not show immunomodulatory activity. A final interpretation of the data showed that, despite its chemoprotective capacity, cardanol has a tendency to induce DNA damage. Hence, caution is needed if this compound is used as a chemopreventive agent. Also, this compound is likely not suitable as an adjuvant in chemotherapy treatments that use cyclophosphamide.

Evaluation of the Intestinal Absorption Mechanism of Casearin X in Caco-2 Cells with Modified Carboxylesterase Activity

The clerodane diterpene casearin X (1), isolated from the leaves of Casearia sylvestris, is a potential new drug candidate due to its potent in vitro cytotoxic activity. In this work, the intestinal absorption mechanism of 1 was evaluated using Caco-2 cells with and without active carboxylesterases (CES). An LC-MS method was developed and validated for the quantification of 1. The estimation of permeability coefficients was possible only under CES-inhibited conditions in which 1 is able to cross the Caco-2 cell monolayer. The mechanism is probably by active transport, with no significant efflux, but with a high retention of the compound inside the cells. The enzymatic hydrolysis assay demonstrates the susceptibility of 1 to first-pass metabolism as substrate for specific CES expressed in human intestine.

Inhibition of tumor proliferation associated with cell cycle arrest caused by extract and fraction from Casearia sylvestris (Salicaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Casearia sylvestris is a tree found in tropical America. In Brazil it is known mainly as Guaçatonga. Literature reports suggest that the leaves and other plant parts have been used by indigenous populations from South America in preparations, mainly aqueous or hydroethanolic macerations or decoctions, most times taken orally for the primary treatment of several diseases, including cancer.

AIM OF THE STUDY

This article reports the results of an investigation about the antiproliferative effects of Casearia sylvestris on tumor cells in vitro and in vivo.

MATERIAL AND METHODS

Aqueous ethanolic maceration and column chromatography were done to obtain a crude aqueous ethanolic extract (CAE) and a chloroform fraction (f-CHCl3). The human breast cancer cell line MCF-7 was used in culture. In vitro, non-cytotoxic concentrations were determined by MTT assay and the antiproliferative effect was assessed by the colony forming unit assay using non-cytotoxic concentrations. Effects on the cell cycle were observed through flow cytometry using a propidium iodide kit. Casearin C was identified in f-CHCl3 by chromatography and H(1) nuclear magnetic resonance. The effect on some key proteins of DNA damage (phosphorylation on the histone H2AX) and cell cycle control (p53, p16, cdk2) was evaluated through immunoblot. Antiproliferative effects in vivo were measured in tumor tissue from Ehrlich ascites-bearing mice through the (3)H-thymidine uptake assay and the trypan blue exclusion method.

RESULTS

In vitro, EC50 values found at 24 h on MCF-7 cells were 141 µg/mL for CAE and 66 µg/mL for f-CHCl3. Inhibition on proliferation was recorded at concentrations as low as 4 µg/mL in the case of the f-CHCl3 (up to 40%) and up to 50% when CAE was added at 9 µg/mL. The cell cycle arrest was demonstrated by the reduction in terms of number of cells in phases G2/M and S, up to 38.9% and 51.9% when cells were treated with CAE, and 53.9% and 66.2%, respectively, when cells were treated with f-CHCl3. The number of cells in G1 was increased when the cells were treated with CAE (21.4%) or f-CHCl3 (27.8%). Key proteins of cell cycle control were affected. The treatments caused activation of p53, p16 and DNA damage found by the appearance of bands corresponding to γ-H2AX. The treatments caused inhibition of cdk2. CAE and particularly f-CHCl3 caused significant inhibition on tumor growth in mice (40% and 60%, respectively). Uptake of (3)H-thymidine, thus proliferation was reduced in tumor cells from mice treated with CAE (>30%) or f-CHCl3 (up to 50%) compared to cells from control animals. Data from the trypan blue assay indicating a lower number of tumor cells in treated animals. From the overall, data from this study are in line with the traditional claims for the antitumor effect of Casearia sylvestris.

CONCLUSIONS

This investigation suggests that whether the extracts from Casearia sylvestris are cytotoxic at high concentrations, lower concentrations have antiproliferative effect and could be useful to complement conventional cytotoxic chemotherapy, and should be evaluated further.

Mutagenicity of ipriflavone in vivo and in vitro

Ipriflavone (7-isopropoxy-isoflavone) is a semisynthetic isoflavone derivative from daidzein and prescribed to prevent and treat osteoporosis in postmenopausal women. In the present study, ipriflavone was investigated with regard to their cytotoxic and mutagenic effects using the micronucleus assay (MN) in vivo on cells of bone marrow and peripheral blood of Swiss albino mice and the micronucleus test with the cytokinesis-blocked micronucleus assay (CBMN assay) on human peripheral blood lymphocytes. The studies were performed in mice with three dosages of the drug, 1.71, 8.57 and 42.85 mg/kg bw in single oral exposure, and for two dosages, 5 and 10 μg/mL in the CBMN assay. Ipriflavone, in the dosages tested, did not differ from controls neither in the induction of MN nor induced cytotoxicity to cells in the in vivo test. However, in the CBMN assay, the concentration of 10 μg/mL induced a statistically significant increase in MN formation and decreased cell proliferation, demonstrating to be mutagenic and cytotoxic at this concentration.