Effect of ketoconazole, a cytochrome P450 inhibitor, on the efficacy of quinine and halofantrine against Schistosoma mansoni in mice

Evaluation of the prophylactic and therapeutic efficacies of mucus and tissue nucleoproteins extracted from Biomphalaria alexandrina snails on schistosomiasis mansoni

Schistosomiasis is a neglected tropical disease with considerable morbidity. The lone effective drug, praziquantel (PZQ), is showing emergence of drug resistance hence, searching for new supportive treatment is crucial. This study aimed to evaluate the efficacy of mucus and nucleoproteins (NPs) extracted from Biomphalaria alexandrina (B. alexandrina) snails on miracidia, cercariae and Schistosoma mansoni (S. mansoni) adults in vitro and assess their experimental in vivo effect through parasitological, histopathological, and biochemical parameters. The in vivo study included 90 male Swiss albino mice. Mice were grouped into 9 groups; G1-G5 were infected and treated with; GI: PZQ, GII: mucus, GIII: combined PZQ and mucus, GIV: NPs, GV: combined PZQ and NPs. Control groups; C1: Non infected non treated (negative control), C2: Infected non treated (positive control), C3: Non infected mucus treated and C4: Non infected NPs treated. The in vitro study proved that the mucus had a better lethal effect on cercariae than miracidia, while NPs had better lethal effect on miracidia. The mucus lethal effect on adults surpassed the NPs as 100% and 60%, respectively. The in vivo study proved that the combined NPs or mucus with PZQ added to the effect of individual PZQ resulting in 100% total worm burden (TWB) reduction. As regard oxidative stress markers, the lowest level of nitric oxide (NO) was shown with combined PZQ and NPs. While, the highest glutathione (GSH) level was produced by individual PZQ. The study concluded that mucus and NPs of B. alexandrina had cercaricidal, miracidicidal and anti-schistosomal effect in vitro and that their combination could be considered a contribution to PZQ potentiality in vivo.

Anti-fibrotic Effect of Oral Versus Intraperitoneal Administration of Gold Nanoparticles in Hepatic Schistosoma mansoni-Infected Mice

BACKGROUND

Schistosomiasis significantly impacts public health, as it causes severe morbidity. Infections caused by Schistosoma mansoni (S. mansoni) can be treated with gold nanoparticles (AuNPs). This study aims to determine the most effective route of AuNPs administration and the magnitude of its anti-fibrotic effect.

METHODS

In the five groups' in vivo assay design, AuNPs were administered intraperitoneally (1 mg/kg) and orally (1 mg/100 g) to S. mansoni-infected mice. Biochemical parameters (serum levels of albumin and liver enzymes alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. The histological changes of the liver in distinct groups were evaluated using Hematoxylin and Eosin, Masson's trichrome, and immunohistochemical stains.

RESULTS

Infection with S. mansoni was associated with substantial changes in the histological architecture of liver tissue and abnormal levels of hepatic function tests (albumin, AST, and ALT). Schistosoma infected hepatocytes exhibited an abnormal microscopic morphology, granuloma formation and aggressive fibrosis. AuNPs restored the liver histological architecture with a highly significant anti-fibrotic effect and significantly corrected hepatic function test levels. Intraperitoneal administration of AuNPs resulted in the most significant anti-fibrotic effect against hepatic S. mansoni infection as observed in all histological sections with Masson's trichrome being the best stain to represent this fact.

CONCLUSION

For treating S. mansoni-induced chronic liver fibrosis, intraperitoneal administration of AuNPs is a successful and effective route of administration that can be recommended.

Screening and verification of CYP3A4 inhibitors from Bushen-Yizhi formula to enhance the bioavailability of osthole in rat plasma

ETHNOPHARMACOLOGICAL RELEVANCE

With the features of multiple-components and targets as well as multifunction, traditional Chinese medicine (TCM) has been widely used in the prevention and treatment of various diseases for a long time. During the application of TCM, the researches about bioavailability enhancement of the bioactive constituents in formula are flourishing. Bushen-Yizhi formula (BSYZ), a TCM prescription with osthole (OST) as one of the main bioactive ingredients, have been widely used to treat kidney deficiency, mental retardation and Alzheimer's disease. However, the underlying biological mechanism and compound-enzyme interaction mediated bioavailability enhancement of OST are still not clearly illuminated.

AIM OF THE STUDY

The aim of this study is to explore the material basis and molecular mechanism from BSYZ in the bioavailability enhancement of OST. Screening the potential CYP3A4 inhibitors using theoretical prediction and then verifying them in vitro, and pharmacokinetics study of OST in rat plasma under co-administrated of screened CYP3A4 inhibitors and BSYZ were also scarcely reported.

MATERIALS AND METHODS

Screening of CYP3A4 inhibitors from BSYZ was performed with molecular docking simulation from systems pharmacology database. The screened compounds were verified by using P450-Glo Screening Systems. A multiple reaction monitoring (MRM) mass spectrometry method was established for OST quantification. Male Sprague-Dawley rats divided into four groups and six rats in each group were employed in the pharmacokinetics study of OST. The administrated conditions were group I, OST (20 mg/kg); group II, BSYZ (containing OST 1 mg/mL, at the dose of 20 mg/kg OST in BSYZ); group III, co-administration of ketoconazole (Ket, 75 mg/kg) and OST (20 mg/kg); group IV, co-administration of CYP3A4 inhibitor (10 mg/kg) and OST (20 mg/kg). They were determined by using HPLC-MS/MS (MRM) and statistical analysis was performed using student's t-test with p < 0.05 as the level of significance.

RESULTS

21 potential CYP3A4 inhibitors were screened from BSYZ compounds library. From the results of verification in vitro, we found 4 compounds with better CYP3A4 inhibition efficiency including Oleic acid, 1,2,3,4,6-O-Pentagalloylglucose, Rutin, and Schisantherin B. Under further verification, Schisantherin B exhibited the best inhibitory effect on CYP3A4 (IC₅₀ = 0.339 μM), and even better than the clinically used drug (Ket) at the concentration of 5 μM. In the study of pharmacokinetics, the area under the curve (AUC, ng/L*h) of OST after oral administration of BSYZ, Ket and Schisantherin B (2196.23 ± 581.33, 462.90 ± 92.30 and 1053.03 ± 263.62, respectively) were significantly higher than that of pure OST treatment (227.89 ± 107.90, p < 0.01).

CONCLUSIONS

Schisantherin B, a profoundly effective CYP3A4 inhibitor screened from BSYZ antagonized the metabolism of CYP3A4 on OST via activity inhibition, therefore significantly enhanced the bioavailability of OST in rat plasma. The results of this study will be helpful to explain the rationality of the compatibility in TCM formula, and also to develop new TCM formula with more reasonable drug compatibility.

The effect of ivermectin alone and in combination with cobicistat or elacridar in experimental Schistosoma mansoni infection in mice

Schistosoma mansoni is less susceptible to the antiparasitic drug ivermectin than other helminths. By inhibiting the P-glycoprotein or cytochrome P450 3A in mice host or parasites in a murine model, we aimed at increasing the sensitivity of S. mansoni to the drug and thus preventing infection. We assigned 124 BALB/c mice to no treatment, treatment with ivermectin only or a combination of ivermectin with either cobicistat or elacridar once daily for three days before infecting them with 150 S. mansoni cercariae each. The assignment was done by batches without an explicit randomization code. Toxicity was monitored. At eight weeks post-infection, mice were euthanized. We determined number of eggs in intestine and liver, adult worms in portal and mesenteric veins. Disease was assessed by counting granulomas/cm² of liver and studying organ weight indices and total weight. IgG levels in serum were also considered. No difference between groups treated with ivermectin only or in combination with cobicistat or elacridar compared with untreated, infected controls. Most mice treated with ivermectin and elacridar suffered severe neurological toxicity. In conclusion, systemic treatment with ivermectin, even in the presence of pharmacological inhibition of P-glycoprotein or cytochrome P450 3A, did not result in effective prophylaxis for S. mansoni infection in an experimental murine model.

Lung cancer cells survive epidermal growth factor receptor tyrosine kinase inhibitor exposure through upregulation of cholesterol synthesis

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) provide clinical benefits over chemotherapy for lung cancer patients with EGFR activating mutations. Despite initial clinical responses, long-term efficacy is not possible because of acquired resistance to these therapies. We have developed EGFR TKI drug-tolerant (DT) human lung cancer cell lines as a model for de novo resistance. Mass spectroscopic analysis revealed that the cytochrome P450 protein, CYP51A1 (Lanosterol 14α-demethylase), which is directly involved with cholesterol synthesis, was significantly upregulated in the DT cells. Total cellular cholesterol, and more specifically, mitochondrial cholesterol, were found to be upregulated in DT cells. We then used the CYP51A1 inhibitor, ketoconazole, to downregulate cholesterol synthesis. In both parental and DT cells, ketoconazole and EGFR TKIs acted synergistically to induce apoptosis and overcome the development of EGFR tolerance. Lastly, this combination therapy was shown to shrink the growth of tumors in an in vivo mouse model of EGFR TKI resistance. Thus, our study demonstrates for the first time that ketoconazole treatment inhibits upregulation of mitochondrial cholesterol and thereby overcomes EGFR-TKI resistance in lung cancer cells.

Cytochrome P450/ABC transporter inhibition simultaneously enhances ivermectin pharmacokinetics in the mammal host and pharmacodynamics in Anopheles gambiae

Mass administration of endectocides, drugs that kill blood-feeding arthropods, has been proposed as a complementary strategy to reduce malaria transmission. Ivermectin is one of the leading candidates given its excellent safety profile. Here we provide proof that the effect of ivermectin can be boosted at two different levels by drugs inhibiting the cytochrome or ABC transporter in the mammal host and the target mosquitoes. Using a mini-pig model, we show that drug-mediated cytochrome P450/ABC transporter inhibition results in a 3-fold increase in the time ivermectin remains above mosquito-killing concentrations. In contrast, P450/ABC transporter induction with rifampicin markedly impaired ivermectin absorption. The same ketoconazole-mediated cytochrome/ABC transporter inhibition also occurs outside the mammal host and enhances the mortality of Anopheles gambiae. This was proven by using the samples from the mini-pig experiments to conduct an ex-vivo synergistic bioassay by membrane-feeding Anopheles mosquitoes. Inhibiting the same cytochrome/xenobiotic pump complex in two different organisms to simultaneously boost the pharmacokinetic and pharmacodynamic activity of a drug is a novel concept that could be applied to other systems. Although the lack of a dose-response effect in the synergistic bioassay warrants further exploration, our study may have broad implications for the control of parasitic and vector-borne diseases.

Evaluation of the Anti-schistosomal Effects of Turmeric (Curcuma longa) Versus Praziquantel in Schistosoma mansoni Infected Mice

BACKGROUND

Curcumin is the major active ingredient of Curcuma longa L., traditionally known as turmeric and has been shown to exhibit a wide range of pharmacological activities including anti-parasitic effect. However, it is found to be water-insoluble and has low bioavailability. The aim of this study was to explore the potential role of turmeric solved in olive oil either alone or in combination with praziquantel (PZQ) in treatment of schistosomiasis mansoni.

METHODS

The whole turmeric powder suspended in olive oil (as a solvent) is indicated to S. mansoni-infected mice aiming to study its potential therapeutic role, either alone or in combination with PZQ.

RESULTS

Turmeric significantly reduced S. mansoni worm burden and complete absence of adult worms achieved in mice treated with combination of turmeric and PZQ. Turmeric has slight non-significant effect on the oogram pattern in all examined S. mansoni infected mice. Turmeric and PZQ found to exert a significant reduction of granuloma size in comparison with control. However, turmeric has a non-significant effect on granuloma number. On the other hand, turmeric or/and PZQ treated mice showed obvious improvement of pathology with mild cloudy swelling and less hydropic degeneration.

CONCLUSION

Turmeric significantly reduced parasite worm burden, granuloma size and consequently the pathology of affected liver, it still far less effective than PZQ.

Dietary accumulation of tetrabromobisphenol A and its effects on the scallop Chlamys farreri

Tetrabromobisphenol A (TBBPA) is currently the most widely-used brominated flame retardant (BFR) and has been proven to have a very high toxicity to aquatic organisms including bivalves. In this study, a laboratory experiment was conducted to obtain a better understanding of the role of algae food on the bioaccumulation of TBBPA and its effects on the suspension-feeding bivalve, the scallop, Chlamys farreri. Scallops were exposed to TBBPA via algae food alone or food+water for 10 days. Results showed that TBBPA was accumulated rapidly by scallops, reaching an approximate steady state in soft tissues within 3 days. The primary route of TBBPA accumulation was via the water, while dietary uptake was relatively minor. TBBPA exposure led to significant inhibition on microsomal cytochrome P450 and cytochrome b5 levels in gills and digestive gland, whereas GST activity and GSH level increased significantly, which indicated that TBBPA could be a suitable substrate to directly participate in phase II metabolism. TBBPA clearly induced the activity of SOD, suggesting the oxidant stress induced by TBBPA. This study suggests that dietary uptake was not the predominant uptake route for TBBPA in bivalves and also provides a preliminary basis for studying the detoxification and antioxidant responses of marine bivalves upon exposure to TBBPA.