Differential Lipid Accumulation on HepG2 Cells Triggered by Palmitic and Linoleic Fatty Acids Exposure

Allergic inflammation triggers dyslipidemia via IgG signalling

BACKGROUND

Allergic diseases begin early in life and are often chronic, thus creating an inflammatory environment that may precede or exacerbate other pathologies. In this regard, allergy has been associated to metabolic disorders and with a higher risk of cardiovascular disease, but the underlying mechanisms remain incompletely understood.

METHODS

We used a murine model of allergy and atherosclerosis, different diets and sensitization methods, and cell-depleting strategies to ascertain the contribution of acute and late phase inflammation to dyslipidemia. Untargeted lipidomic analyses were applied to define the lipid fingerprint of allergic inflammation at different phases of allergic pathology. Expression of genes related to lipid metabolism was assessed in liver and adipose tissue at different times post-allergen challenge. Also, changes in serum triglycerides (TGs) were evaluated in a group of 59 patients ≥14 days after the onset of an allergic reaction.

RESULTS

We found that allergic inflammation induces a unique lipid signature that is characterized by increased serum TGs and changes in the expression of genes related to lipid metabolism in liver and adipose tissue. Alterations in blood TGs following an allergic reaction are independent of T-cell-driven late phase inflammation. On the contrary, the IgG-mediated alternative pathway of anaphylaxis is sufficient to induce a TG increase and a unique lipid profile. Lastly, we demonstrated an increase in serum TGs in 59 patients after undergoing an allergic reaction.

CONCLUSION

Overall, this study reveals that IgG-mediated allergic inflammation regulates lipid metabolism.

Preparation and characterization of nano-emulsion formulations of Asparagus densiflorus root and aerial parts extracts: evaluation of in-vitro antibacterial and anticancer activities of nano-emulsion versus pure plant extract

OBJECTIVE

Preparation and characterization of nano-emulsion formulations for Asparagus densiflorus aerial and root parts extracts.

SIGNIFICANCE

Genus Asparagus is known for its antimicrobial and anticancer activities, however, freeze dried powder of aqueous - alcoholic extract prepared in this study, exhibited a limited water solubility, limiting its therapeutic application. Thus, encapsulation of its phytochemicals into nano-emulsion is proposed as a solution to improve water solubility, and facilitate its clinical translation.

METHODS

the composition of extracts for both aerial and root parts of Asparagus densiflorus was identified by HPLC and LC-MS analysis. Nano-emulsion was prepared via homogenization where a mixture of Castor oil: phosphate buffered saline (10 mM, pH 7.4): Tween 80: PEG 600 in a ratio of 10: 5: 2.5: 2.5, respectively. Nano-emulsion formulations were characterized for particle size, polydispersity index (PDI), zeta potential, TEM, viscosity and pH. Then, the antibacterial and anticancer activities of nano-emulsion formulations versus their pure plant counterparts was assessed.

RESULTS

The analysis of extracts identified several flavonoids, phenolics, and saponins which were reported to have antimicrobial and anticancer activities. Nano-emulsion formulations were monodispersed with droplet sizes ranging from 80.27 ± 2.05 to 111.16 ± 1.97 nm, and polydispersity index ≤0.3. Nano-emulsion formulations enhanced significantly the antibacterial (multidrug resistant bacteria causing skin and dental soft tissues infections) and anticancer (HuH7, HEPG2, H460 and HCT116) activities compared to their pure plant extract counterparts.

CONCLUSION

Employing a nano-delivery system as a carrier for phytochemicals might be an effective strategy to enhance their pharmacological activity, overcome their limitations, and ultimately increase their potential for clinical applications.

Sea cucumber plasmalogen enhance lipophagy to alleviate abnormal lipid accumulation induced by high-fat diet

Sea cucumber phospholipids, including the plasmalogen (PlsEtn) and plasmanylcholine (PakCho), have been shown to play a regulatory role in lipid metabolism disorders, but their mechanism of action remains unclear. Therefore, high-fat diet (HFD) and palmitic acid were used to establish lipid accumulation models in mice and HepG2 cells, respectively. Results showed that PlsEtn can reduce lipid deposition both in vivo and in vitro. HFD stimulation abnormally activated lipophagy through the phosphorylation of the AMPK/ULK1 pathway. The lipophagy flux monitor revealed abnormalities in the fusion stage of lipophagy. Of note, only PlsEtn stimulated the dynamic remodeling of the autophagosome membrane, which was indicated by the significantly decreased LC3 II/I ratio and p62 level. In all experiments, the effect of PlsEtn was significantly higher than that of PakCho. These findings elucidated the mechanism of PlsEtn in alleviating lipid accumulation, showed that it might be a lipophagy enhancer, and provided new insights into the high-value utilization of sea cucumber as an agricultural resource.

Use of Various Sugarcane Byproducts to Produce Lipid Extracts with Bioactive Properties: Physicochemical and Biological Characterization

Sugarcane, a globally cultivated crop constituting nearly 80% of total sugar production, yields residues from harvesting and sugar production known for their renewable bioactive compounds with health-promoting properties. Despite previous studies, the intricate interplay of extracts from diverse sugarcane byproducts and their biological attributes remains underexplored. This study focused on extracting the lipid fraction from a blend of selected sugarcane byproducts (straw, bagasse, and filter cake) using ethanol. The resulting extract underwent comprehensive characterization, including physicochemical analysis (FT-IR, DSC, particle size distribution, and color) and chemical composition assessment (GC-MS). The biological properties were evaluated through antihypertensive (ACE), anticholesterolemic (HMG-CoA reductase), and antidiabetic (alpha-glucosidase and Dipeptidyl Peptidase-IV) assays, alongside in vitro biocompatibility assessments in Caco-2 and Hep G2 cells. The phytochemicals identified, such as β-sitosterol and 1-octacosanol, likely contribute to the extract's antidiabetic, anticholesterolemic, and antihypertensive potential, given their association with various beneficial bioactivities. The extract exhibited substantial antidiabetic effects, inhibiting α-glucosidase (5-60%) and DPP-IV activity (25-100%), anticholesterolemic potential with HMG-CoA reductase inhibition (11.4-63.2%), and antihypertensive properties through ACE inhibition (24.0-27.3%). These findings lay the groundwork for incorporating these ingredients into the development of food supplements or nutraceuticals, offering potential for preventing and managing metabolic syndrome-associated conditions.

Impaired hepatic lipid metabolism and biomarkers in fatty liver disease

The liver plays a crucial role in lipid metabolism and metabolic homeostasis. Non-Alcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease worldwide and currently has no specific treatments. Lifestyle modifications such as weight loss, exercise, and dietary changes are recommended to reduce the risk factors associated with the disease. Oxidized cholesterol products, some phospholipids and diacylglycerols can activate inflammatory pathways and contribute to the progression to Non-Alcoholic Steatohepatitis. Monitoring the whole plasma and liver lipidome may provide insights into the onset, development, and prevention of inflammatory-related diseases. As Lipid Droplets (LDs) represent augmented lipid reservoirs in NAFLD, new developments are being made on different therapies focused on LD associated proteins modulation (seipin, PLIN-2), as well as LD lipophagy mechanisms. The information covered in this publication provides an overview of the available research on lipid biomarkers linked to NAFLD and can be used to guide the development of future pharmacological therapies.

The Involvement of Polyunsaturated Fatty Acids in Apoptosis Mechanisms and Their Implications in Cancer

Cancer is a significant global public health issue and, despite advancements in detection and treatment, the prognosis remains poor. Cancer is a complex disease characterized by various hallmarks, including dysregulation in apoptotic cell death pathways. Apoptosis is a programmed cell death process that efficiently eliminates damaged cells. Several studies have indicated the involvement of polyunsaturated fatty acids (PUFAs) in apoptosis, including omega-3 PUFAs such as alpha-linolenic acid, docosahexaenoic acid, and eicosapentaenoic acid. However, the role of omega-6 PUFAs, such as linoleic acid, gamma-linolenic acid, and arachidonic acid, in apoptosis is controversial, with some studies supporting their activation of apoptosis and others suggesting inhibition. These PUFAs are essential fatty acids, and Western populations today have a high consumption rate of omega-6 to omega-3 PUFAs. This review focuses on presenting the diverse molecular mechanisms evidence in both in vitro and in vivo models, to help clarify the controversial involvement of omega-3 and omega-6 PUFAs in apoptosis mechanisms in cancer.