High-fat diet induced alteration in lipid enzymes and inflammation in cardiac and brain tissues: Assessment of the effects of Atorvastatin-loaded nanoparticles

Comparative toxicity of zinc oxide nanoparticles and zinc salts in male mice: Hematological, biochemical, and histopathological impacts

The aim of this study was to investigate the toxicity of zinc oxide nanoparticles (ZnO NPs) compared to different zinc salts (ZnSO4, Zn(NO3)2, and ZnCl2) in male mice. For this purpose, 45 male mice were divided into five groups of nine (one control group). Mice were exposed to ZnO NPs and various zinc salts for 28 days, while the control group remained unexposed. After the exposure period, the mice were euthanized, and hematological, biochemical, enzymatic, and histopathological changes were recorded. Most hematological (RBC, WBC, Hb, Ht counts), biochemical (cholesterol, triglyceride, glucose, total protein, and albumin), and enzymatic parameters alkaline phosphatase (ALP), aspartate transaminase (AST), alanine aminotransferase (ALT) were significantly different in exposed mice compared to the control group (p < 0.05). The number of erythrocytes in mice exposed to ZnCl2 for 28 days (7.84 ± 1.41 × 106 mm3) was significantly lower than in the control group (10.11 ± 1.14 ×106 mm3) (p < 0.05). Additionally, mice exposed to ZnCl2 had significantly lower white blood cell (WBC) counts, hemoglobin (Hb), and hematocrit (Ht) levels than the control group (p < 0.05). Zn-exposed mice developed deformed erythrocytes, including dacrocytes, keratocytes, and ovalocytes, likely due to cytogenetically damaged RBC precursors. ZnO NPs and its various salts caused degeneration in hepatocytes, thickening and inflammatory cell infiltration in the renal capsule, congestion in the blood vessels of the lungs, and swelling of goblet cells in the intestine. Adding to the wealth of literature on the toxicity of ZnO NPs and zinc salts, especially ZnCl2, our study highlights the ecotoxicity of these compounds in mice. Effective and timely measures should be taken to reduce the use of ZnO NPs and its various salts worldwide.

Targeted Strategy in Lipid-Lowering Therapy

Dyslipidemia is characterized by a diminished lipid profile, including increased level of total cholesterol and low-density lipoprotein cholesterol (LDL-c) and reduced level of high-density lipoprotein cholesterol (HDL-c). Lipid-lowering agents represent an efficient tool for the prevention or reduction of progression of atherosclerosis, coronary heart diseases and metabolic syndrome. Statins, ezetimibe, and recently proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are the most effective and used drugs in clinical lipid-lowering therapy. These drugs are mainly aimed to lower cholesterol levels by different mechanisms of actions. Statins, the agents of the first-line therapy-known as 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors-suppress the liver cholesterol synthesis. Ezetimibe as the second-line therapy can decrease cholesterol by inhibiting cholesterol absorption. Finally, the PCSK9 inhibitors act as an inducer of LDL excretion. In spite of their beneficial lipid-lowering properties, many patients suffer from their serious side effects, route of administration, or unsatisfactory physicochemical characteristics. Clinical demand for dose reduction and the improvement of bioavailability as well as pharmacodynamic and pharmacokinetic profile has resulted in the development of a new targeted therapy that includes nanoparticle carriers, emulsions or vaccination often associated with another more subtle form of administration. Targeted therapy aims to exert a more potent drug profile with lipid-lowering properties either alone or in mutual combination to potentiate their beneficial effects. This review describes the most effective lipid-lowering drugs, their favorable and adverse effects, as well as targeted therapy and alternative treatments to help reduce or prevent atherosclerotic processes and cardiovascular events.