Natural Products and Small Molecules Targeting Cellular Ceramide Metabolism to Enhance Apoptosis in Cancer Cells

Bioactive lipid signaling and lipidomics in macrophage polarization: Impact on inflammation and immune regulation

Macrophages, crucial innate immune cells, defend against pathogens and resolve inflammation, maintaining tissue balance. They perform phagocytosis, present antigens to T cells, and bond innate and adaptive immunity through various activation states. Classical activation is associated with Th1 responses and interferon γ production, while alternative activation, induced by interleukin 4, is characterized by increased endocytosis, reduced secretion of pro-inflammatory cytokines, and roles in immunoregulation and tissue remodeling. Although these represent opposite extremes observed in vitro, the remarkable plasticity of macrophages allows for a wide spectrum of activation phenotypes that are complex to characterize experimentally. While the application of omics techniques has resulted in significant advances in the characterization of macrophage polarization, lipidomic studies have received lesser attention. Beyond their role as structural components and energy sources, lipids function as signaling molecules that regulate macrophage activation and polarization, thereby shaping immune responses. This work reviews the interaction between lipid signaling and macrophage polarization, exploring how lipid metabolism influences macrophage phenotype and function. These insights offer potential therapeutic strategies for immune-mediated diseases and inflammation-related disorders, including inflammaging.

Ceramides and Skin Health: New Insights

Ceramide has transitioned from an incidental discovery to a vital element in skincare, becoming a thoroughly studied compound in the quest to treat skin conditions. Creating a moisture barrier, preserving hydration, regulating pH, controlling inflammation, and enhancing skin functions and appearance are among its established benefits. It is often used medically to repair skin barrier defects, as observed in inflammatory skin conditions like atopic dermatitis (AD) and dry skin types. Furthermore, ceramide and its metabolites are commonly used as predictors before disease manifestation and for prognostication processes, thus can be used as biomarker for clinical diagnosis as well. In the last couple of decades, momentum was also seen in the pre-clinical studies involving anti-cancer and nanotechnology field, whereby ceramide was also used as a drug, a carrier, or even adjunct formulation to increase efficacy of treatment such as chemotherapy. Approaches to increase ceramide levels include directly replenishing lost ceramides with natural extracts, synthetic pseudo-ceramides, or ceramide-like analogues, as well as using supplements that stimulate the body's natural ceramide production. Although ceramide is a well-known treatment in skincare and for common skin conditions like AD and psoriasis, its development and related pharmacology for severe skin conditions, such as skin cancer, remain in pre-clinical stages. Hence, the purpose of this research is to explore the role of ceramide in skin health and its application in common skin diseases.

In vitro and in silico approaches manifest the anti-leishmanial activity of wild edible mushroom Amanita princeps

Visceral Leishmaniasis, caused by Leishmania donovani, is the second most deadly parasitic disease, causing over 65,000 deaths annually. Synthetic drugs available in the market, to combat this disease, have numerous side effects. In this backdrop, we aim to find safer antileishmanial alternatives with minimal side effects from mushrooms, which harbour various secondary metabolites with promising efficacy. Robust screening of sixteen extracts from eight different wild mushrooms reveals that the hydroalcoholic extract of Amanita princeps has outstanding antileishmanial activity against Leishmania donovani. Metabolomic profiling of this lead extract identifies 50 bioactive mycocompounds and among them, 10 were selected for in-silico study against five major targets-arginase, spermidine synthase, ornithine decarboxylase, trypanothione reductase and SOD, crucial for thiol-redox balance in parasites in the polyamine synthesis pathway. Molecular docking analysis against our prioritised targets identified two mycompounds Ergosterol and Taraxacolide 1-O-b-D-glucopyranoside from Amanita princeps having the highest binding affinity of -15.8 and -11.8 kcal/mol respectively against the ornithine decarboxylase of polyamine synthesis pathway. However, MD simulations and free energy calculation using MM-GBSA analysis revealed the better stability of ergosterol with PASP receptors suggesting its promising role as an anti-leishmanial compound. Further results of in vitro arginase, SOD, and NO enzyme assays also corroborated with in-silico findings, reinforcing the anti-leishmanial efficacy of the Amanita princeps extract. Thus, both in silico and in vitro analyses suggest the efficacy of both Ergosterol and Taraxacolide 1-O-b-D-glucopyranoside compounds resourced from Amanita princeps as potent antileishmanial agents.

Graphical abstract

Hepatotoxicity assessment of innovative nutritional supplements based on olive-oil formulations enriched with natural antioxidants

Introduction

This study focuses on the assessment of extra virgin olive-oil and olive fruit-based formulations enriched with natural antioxidants as potential nutritional supplements for alleviating symptoms and long-term consequences of illnesses whose molecular pathophysiology is affected by oxidative stress and inflammation, such as Alzheimer's disease (AD).

Methods

Besides evaluating cell viability and proliferation capacity of human hepatocellular carcinoma HepG2 cells exposed to formulations in culture, hepatotoxicity was also considered as an additional safety measure using quantitative real-time PCR on RNA samples isolated from the cell cultures and applying approaches of targeted molecular analysis to uncover potential pathway effects through gene expression profiling. Furthermore, the formulations investigated in this work contrast the addition of natural extract with chemical forms and evaluate the antioxidant delivery mode on cell toxicity.

Results

The results indicate minimal cellular toxicity and a significant beneficial impact on metabolic molecular pathways in HepG2 cell cultures, thus paving the way for innovative therapeutic strategies using olive-oil and antioxidants in dietary supplements to minimize the long-term effects of oxidative stress and inflammatory signals in individuals being suffered by disorders like AD.

Discussion

Overall, the experimental design and the data obtained support the notion of applying innovative molecular methodologies and research techniques to evidently advance the delivery, as well as the scientific impact and validation of nutritional supplements and dietary products to improve public health and healthcare outcomes.

Mysterious sphingolipids: metabolic interrelationships at the center of pathophysiology

Metabolic pathways are complex and intertwined. Deficiencies in one or more enzymes in a given pathway are directly linked with genetic diseases, most of them having devastating manifestations. The metabolic pathways undertaken by sphingolipids are diverse and elaborate with ceramide species serving as the hubs of sphingolipid intermediary metabolism and function. Sphingolipids are bioactive lipids that serve a multitude of cellular functions. Being pleiotropic in function, deficiency or overproduction of certain sphingolipids is associated with many genetic and chronic diseases. In this up-to-date review article, we strive to gather recent scientific evidence about sphingolipid metabolism, its enzymes, and regulation. We shed light on the importance of sphingolipid metabolism in a variety of genetic diseases and in nervous and immune system ailments. This is a comprehensive review of the state of the field of sphingolipid biochemistry.