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The recent interest in bioactive compounds from natural sources has led to the evolution of the skin care industry. Efforts to develop biologically active ingredients from natural sources have resulted in the emergence of enhanced skin care products. Spirulina (SPR), a nutritionally enriched cyanobacteria-type microalga, is rich in nutrients and phytochemicals. SPR possesses antioxidant, immunomodulatory, and anti-inflammatory activities. Spirulina-loaded bilosomes (SPR-BS), a novel antiaging drug delivery system, were designed for the first time by incorporation in a lecithin–bile salt-integrated system for bypassing skin delivery obstacles. The optimized BS had good entrapment efficiency, small particle size, optimal zeta potential, and sustained drug release pattern. Blank and SPR-loaded BS formulations were safe, with a primary irritancy index of <2 based on the Draize test. In vivo tests were conducted, and photoprotective antiaging effects were evaluated visually and biochemically by analyzing antioxidant, anti-inflammatory, and anti-wrinkling markers following ultraviolet (UV) B irradiation. Results of biochemical marker analysis and histopathological examination confirmed the superior antiaging effect of SPR-BS compared with SPR. Thus, SPR-loaded BS is a promising nanoplatform for SPR delivery, can be used for treating UV-induced skin damage, and offers maximum therapeutic outcomes. [ABSTRACT FROM AUTHOR]

Preparation and evaluation of a non-invasive intranasal luteolin delivery for the management of cognitive dysfunction in Alzheimer's disease (AD) using novel chitosan decorated nanoparticles. Development of luteolin-loaded chitosomes was followed by full in vitro characterization. In vivo efficacy was evaluated using a sporadic Alzheimer's disease (SAD) animal model via intracerebroventricular injection of 3 mg/kg streptozotocin (ICV-STZ). Treatment groups of luteolin suspension and chitosomes (50 mg/kg) were then intranasally administered after 5 h of ICV-STZ followed by everyday administration for 21 consecutive days. Behavioral, histological, immunohistochemical, and biochemical studies were conducted. Chitosomes yielded promising quality attributes in terms of particle size (PS) (412.8 ± 3.28 nm), polydispersity index (PDI) (0.378 ± 0.07), Zeta potential (ZP) (37.4 ± 2.13 mv), and percentage entrapment efficiency (EE%) (86.6 ± 2.05%). Behavioral findings showed obvious improvement in the acquisition of short-term and long-term spatial memory. Furthermore, histological evaluation revealed an increased neuronal survival rate with a reduction in the number of amyloid plaques. Biochemical results showed improved antioxidant effects and reduced pro-inflammatory mediators' levels. In addition, a suppression by half was observed in the levels of both Aβ aggregation and hyperphosphorylated-tau protein in comparison to the model control group which in turn confirmed the capability of luteolin-loaded chitosomes (LUT-CHS) in attenuating the pathological changes of AD. The prepared nanoparticles are considered a promising safe, effective, and non-invasive nanodelivery system that improves cognitive function in SAD albino mice as opposed to luteolin suspension. [ABSTRACT FROM AUTHOR]

Background: In previous studies, pyridoxamine (PM) limited the formation of advanced glycation end products (AGEs) and development of nephropathy in streptozotocin-diabetic rats without affecting glycemic control. However, the lipid-lowering effects of PM and the correlation of plasma cholesterol and triglycerides with AGEs in skin collagen suggested that lipids might be an important source of AGEs in the diabetic rat. This study addresses the effects of hyperlipidemia on formation of advanced glycation and lipoxidation end products (AGE/ALEs) and the effects of PM on hyperlipidemia, hypertension, AGE/ALE formation, and development of nephropathy in the nondiabetic, Zucker obese rat.Methods: Three groups of Zucker rats were studied: lean (Fa/fa), untreated fatty (fa/fa), and fa/fa treated with PM (2 g/L drinking water). Blood pressure, plasma lipids and creatinine, and urinary albumin were measured monthly. AGE/ALEs were measured in skin collagen by high-performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Changes in wall thickness of the aorta and renal arterioles were evaluated by light microscopy.Results: AGE/ALEs formation was increased two- to threefold in skin collagen of obese versus lean rats. PM inhibited the increases in AGE/ALEs in collagen, and significantly decreased the rise in plasma triglycerides, cholesterol, and creatinine, corrected hypertension and thickening of the vascular wall, and nearly normalized urinary protein and albumin excretion in Zucker fa/fa rats.Conclusion: Lipids are an important source of chemical modification of tissue proteins, even in the absence of hyperglycemia. PM inhibited AGE/ALE formation and hyperlipidemia and protected against renal and vascular pathology in a nondiabetic model. [ABSTRACT FROM AUTHOR]

Insulin resistance contributes to several disorders including type 2 diabetes and cardiovascular diseases. Carpachromene is a natural active compound that inhibits α-glucosidase enzyme. The aim of the present study is to investigate the potential activity of carpachromene on glucose consumption, metabolism and insulin signalling in a HepG2 cells insulin resistant model. A HepG2 insulin resistant cell model (HepG2/IRM) was established. Cell viability assay of HepG2/IRM cells was performed after carpachromene/metformin treatment. Glucose concentration and glycogen content were determined. Western blot analysis of insulin receptor, IRS1, IRS2, PI3k, Akt, GSK3, FoxO1 proteins after carpachromene treatment was performed. Phosphoenolpyruvate carboxykinase (PEPCK) and hexokinase (HK) enzymes activity was also estimated. Viability of HepG2/IRM cells was over 90% after carpachromene treatment at concentrations 6.3, 10, and 20 µg/mL. Treatment of HepG2/IRM cells with carpachromene decreased glucose concentration in a concentration- and time-dependant manner. In addition, carpachromene increased glycogen content of HepG2/IRM cells. Moreover, carpachromene treatment of HepG2/IRM cells significantly increased the expression of phosphorylated/total ratios of IR, IRS1, PI3K, Akt, GSK3, and FoxO1 proteins. Furthermore, PEPCK enzyme activity was significantly decreased, and HK enzyme activity was significantly increased after carpachromene treatment. The present study examined, for the first time, the potential antidiabetic activity of carpachromene on a biochemical and molecular basis. It increased the expression ratio of insulin receptor and IRS1 which further phosphorylated/activated PI3K/Akt pathway and phosphorylated/inhibited GSK3 and FoxO1 proteins. Our findings revealed that carpachromene showed central molecular regulation of glucose metabolism and insulin signalling via IR/IRS1/ PI3K/Akt/GSK3/FoxO1 pathway. [ABSTRACT FROM AUTHOR]