Benzyl isothiocyanate

Candida albicans is the most prominent conditional fungal pathogen, which can cause systemic candidiasis when an individual becomes immunocompromised. The widespread and long-term use of azoles like fluconazole (FLC) has led to a significant increase in drug resistance, posing substantial challenges to clinical treatment. In our previous study, benzyl isothiocyanate (BITC) was extracted from Carica papaya L. seed, and it exhibited a notable inhibitory effect against C. albicans. However, the application of BITC is restricted by its instability, poor water solubility, volatility, and easy degradation. This study aimed to prepare BITC-loaded nanostructured lipid carrier (BITC-NLC) to address these limitations of BITC and enhance antifungal efficacy in vitro and in vivo against C. albicans. The results of physicochemical properties showed that BITC-NLC had small particle size, good physical stability, and high encapsulation efficiency. In vitro, the antifungal effect of BITC-NLC was better than BITC against both sensitive and resistant C. albicans and better than FLC against resistant C. albicans. Moreover, in the in vivo experiment using systemic candidiasis mice model induced by resistant C. albicans, BITC-NLC was more remarkable than BITC and FLC in the increase of the survival rate and the splenic index, the reduction of the fungal burden, and the alleviation of the pathological damage. These findings may be attributed to the enhanced stability and sustained release of BITC. This study highlights the potential of BITC-NLC as a novel and effective formulation for the clinical treatment of drug-resistant C. albicans infections, thereby expanding the application scope of papaya.

The global prevalence of overweight and obesity has risen sharply over the past few decades as a result of excess calorie intake and sedentary lifestyles. Obesity increases the risk for various metabolic disorders, such as hyperlipidemia, fatty liver disease, and diabetes mellitus. Isothiocyanates, which are abundant in cruciferous vegetables, have been shown to exhibit anticancer, anti-inflammatory, and antioxidant properties. However, the efficacy of benzyl isothiocyanate (BITC) in preventing the adverse effects of obesity, such as hepatic steatosis and insulin resistance, remains uncertain. To address this knowledge gap, we assessed whether BITC protects against hepatic insulin resistance by using primary mouse hepatocytes and AML12 cells treated with palmitic acid (PA) and mice fed a high-fat diet supplemented with cholesterol and cholic acid (HFCCD). We found that the impairments in insulin sensitivity caused by PA, such as decreases in the phosphorylation of insulin receptor substrate (IRS) 1 (Tyr608), Akt, glycogen synthase kinase (GSK) 3β, and FOXO1 and increases in the expression of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase 1 (PEPCK) mRNA in hepatocytes, were mitigated by pretreatment with BITC. BITC also attenuated PA-induced hepatic lipid accumulation and reactive oxygen species production. In vivo, BITC significantly reduced blood glucose levels and the HOMA-IR and inhibited hepatic lipid accumulation, IRS1 phosphorylation at Ser307, and G6Pase and PEPCK expression compared with that in mice fed the HFCCD alone. These results show that BITC ameliorates the lipotoxicity associated with insulin resistance by activating the IR/IRS/Akt/FOXO1 and GSK3β pathways, which leads to decreased gluconeogenesis and increased glycogen synthesis.