Squalene through Its Post-Squalene Metabolites Is a Modulator of Hepatic Transcriptome in Rabbits

Chitosan Nanoparticles, a Novel Drug Delivery System to Transfer Squalene for Hepatocyte Stress Protection

The Mediterranean diet is a well-known dietary pattern that has gained considerable popularity worldwide for its ability to prevent the progression of nonalcoholic fatty liver disease. This is largely attributed to the use of virgin olive oil as the primary source of fat, which contains a substantial amount of squalene, a natural antioxidant. In order to enhance the delivery of squalene and amplify its effects due to its highly hydrophobic nature, herein, squalene has been incorporated into chitosan nanoparticles. The characterization of the resulting nanoparticles was conducted via scanning electron microscopy, dynamic light scattering, ζ potential, Fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry. Reactive oxygen species (ROS) generation and cell viability assays were conducted in oxidative and endoplasmic reticulum (ER) stress in AML12 and a TXNDC5-deficient AML12 cell line, which was generated by CRISPR/Cas9 technology. The results demonstrated that squalene was successfully encapsulated in chitosan nanoparticles and exhibited rapid and efficient cellular uptake at a 150 μM squalene concentration within 48 h. In conclusion, the encapsulation of squalene in chitosan nanoparticles, compared to the poly(d,l-lactide-co-glycolic acid) and ethanol drug carriers, significantly enhanced its cellular uptake. This allows the administration of higher doses, which improve hepatocyte viability and reduce ROS levels, effectively compensating for the adverse effects of TXNDC5 deficiency under the context of hepatocyte stress protection.

Differentially Expressed Genes in Response to a Squalene-Supplemented Diet Are Accurate Discriminants of Porcine Non-Alcoholic Steatohepatitis

Squalene is the major unsaponifiable component of virgin olive oil, the fat source of the Mediterranean diet. To evaluate its effect on the hepatic transcriptome, RNA sequencing was carried out in two groups of male Large White x Landrace pigs developing nonalcoholic steatohepatitis by feeding them a high fat/cholesterol/fructose and methionine and choline-deficient steatotic diet or the same diet with 0.5% squalene. Hepatic lipids, squalene content, steatosis, activity (ballooning + inflammation), and SAF (steatosis + activity + fibrosis) scores were analyzed. Pigs receiving the latter diet showed hepatic squalene accumulation and twelve significantly differentially expressed hepatic genes (log2 fold change < 1.5 or <1.5) correlating in a gene network. These pigs also had lower hepatic triglycerides and lipid droplet areas and higher cellular ballooning. Glutamyl aminopeptidase (ENPEP) was correlated with triglyceride content, while alpha-fetoprotein (AFP), neutralized E3 ubiquitin protein ligase 3 (NEURL3), 2'-5'-oligoadenylate synthase-like protein (OASL), and protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B) were correlated with activity reflecting inflammation and ballooning, and NEURL3 with the SAF score. AFP, ENPEP, and PPP1R1B exhibited a remarkably strong discriminant power compared to those pathological parameters in both experimental groups. Moreover, the expression of PPP1R1B, TMEM45B, AFP, and ENPEP followed the same pattern in vitro using human hepatoma (HEPG2) and mouse liver 12 (AML12) cell lines incubated with squalene, indicating a direct effect of squalene on these expressions. These findings suggest that squalene accumulated in the liver is able to modulate gene expression changes that may influence the progression of non-alcoholic steatohepatitis.

A Bio-Therapeutically Squalene

Although the skin tissue on our bodies is a well-organized structure with high biomechanical properties like tensile strength and friction, we have all experienced various types of wounds throughout our lives owing to numerous etiological factors. In the general population, it is a substantial source of morbidity. For instance, in the case of burnt skin tissue, self-healing is in fact a large and challenging barrier to tissue regeneration. Squalene is a bioactive triterpene that occurs naturally and plays a key role in the process of making sterols. The most well-known source of squalene is shark liver oil. Vegetable oils may contain squalene in a range of concentrations. They have been extracted using a variety of techniques, including supercritical carbon dioxide, microwave, ultrasonic, cold press, and traditional Soxhlet extractions. In vitro and in animal models, these substances have been demonstrated to have anticancer, antioxidant, drug carrier, detoxifier, skin moisturising, and emollient effects.

A Comprehensive Review of Health-Benefiting Components in Rapeseed Oil

Rapeseed oil is the third most consumed culinary oil in the world. It is well-known for its high content of unsaturated fatty acids, especially polyunsaturated fatty acids, which make it of great nutritional value. There is increasing evidence that a diet rich in unsaturated fatty acids offers health benefits. Although the consumption of rapeseed oil cuts across many areas around the world, the nutritional elements of rapeseed oil and the exact efficacy of the nutrients remain unclear. In this review, we systematically summarized the latest studies on functional rapeseed components to ascertain which component of canola oil contributes to its function. Apart from unsaturated fatty acids, there are nine functional components in rapeseed oil that contribute to its anti-microbial, anti-inflammatory, anti-obesity, anti-diabetic, anti-cancer, neuroprotective, and cardioprotective, among others. These nine functional components are vitamin E, flavonoids, squalene, carotenoids, glucoraphanin, indole-3-Carbinol, sterols, phospholipids, and ferulic acid, which themselves or their derivatives have health-benefiting properties. This review sheds light on the health-benefiting effects of rapeseed oil in the hope of further development of functional foods from rapeseed.