Statine zur Behandlung von Erkrankungen des zentralen Nervensystems

Probiotic Characteristics of Lactiplantibacillus Plantarum N-1 and Its Cholesterol-Lowering Effect in Hypercholesterolemic Rats

In this study, the probiotic potential and treatment effects of Lactiplantibacillus plantarum N-1 in hypercholesterolemic rats were investigated, and the possible regulatory mechanisms of lipid metabolism via short-chain fatty acids (SCFAs) and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase were elucidated. The strain N-1 displayed probiotic properties of antioxidant capacity, adhesion to Caco-2 cells, susceptibility to antibiotics in vitro. The results in animal study showed that the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels in serum and TC in liver declined significantly in both N-1 and simvastatin (Sta) treatment groups compared to the control (P < 0.05), and the extent of these decreases were similar between them. The expression of the HMG-CoA gene in the N-1 group was downregulated significantly by 31.18% compared to the control (P < 0.01), and the contents of butyrate and valerate in N-1 groups were significantly higher than those in both model and Sta group (P < 0.05). Thus, promoting the production of the intestinal SCFAs and inhibiting the expression of HMG-CoA reductase by L. plantarum N-1 may contribute to the improved lipid metabolism and thus lowering cholesterol level in rats. Our investigation indicated that L. plantarum N-1 has the potential to be developed into a functional food supplement for hypercholesterolemia treatment.

The ocular toxicity and pharmacokinetics of simvastatin following intravitreal injection in mice

AIM

To investigate the retinal toxicity and pharmacokinetics of simvastatin intravitreally injected into mice.

METHODS

Forty-eight 6-8-week-old C57BL/6J mice were used in this study. Simvastatin was intravitreally injected into the right eye of each mouse; the left eye was injected with vehicle and was used as a control. Bilateral dark-adapted electroretinography (ERG) was performed 1 and 7d following injection. Histology was examined using a combination of light, fluorescence and electron microscopy. High-performance liquid chromatography (HPLC) was used to determine the decay in the retinal simvastatin concentration.

RESULTS

ERG revealed no significant changes in the simvastatin-injected eyes compared to control. Histologic studies showed normal retinal morphology in eyes injected with simvastatin up to a final vitreal concentration of 200 µmol/L. No significant changes in the number of photoreceptors, bipolar cells or ganglion cells were found. The retinal simvastatin concentration decayed exponentially, with a half-life of 1.92-2.41h.

CONCLUSION

Intravitreal injection of up to 200 µmol/L simvastatin produced no signs of adverse effects in the mouse retina. Simvastatin reaches the retina shortly after intravitreal injectionand has a short half-life.

Simvastatin interferes with process outgrowth and branching of oligodendrocytes

Statins have attracted interest as a treatment option for multiple sclerosis (MS) because of their pleiotropic antiinflammatory and immunomodulatory effects. However, contradictory results have been described when they are applied to oligodendrocytes (OLGs), the cell type predominantly affected in MS. In this study we focus on the in vitro effect of statins on process outgrowth in OLN-93 cells, a well-characterized OLG-derived cell line, and primary cultures of neonatal rat OLGs. Application of the lipophilic simvastatin, as low as 0.1-1 μM, disturbs process formation of both cell types, leading to less ramified cells. We show that both protein isoprenylation and cholesterol synthesis are required for the normal differentiation of OLGs. It is further demonstrated that the expression of 2',3'-cyclic-nucleotide-3' phosphodiesterase (CNP) and tubulin is lowered, concomitant with a reduction of membrane-bound CNP as well as tubulin. Therefore, we propose that lack of isoprenylation of CNP could help to explain the altered morphological and biochemical differentiation state of treated OLGs. Moreover, expression of specific myelin markers, such as myelin basic protein, myelin-associated glycoprotein, and myelin oligodendrocyte glycoprotein, was compromised after treatment. We conclude that simvastatin treatment has detrimental effects on OLG process outgrowth, the prior step in (re)myelination, thereby mortgaging long-term healing of MS lesions.

Lipidsenker- und andere toxische Myopathien

A growing number of therapeutic agents and exogenous toxins are harmful to structure and function of human skeletal muscle. The clinical syndrome encompasses asymptomatic creatine kinase elevation, myalgia, exercise intolerance, muscle paresis and atrophy, and lastly acute rhabdomyolysis. Toxic myopathies are potentially reversible, hence a prompt recognition is particularly helpful for the early diagnosis and in conclusion elimination of a myopathy inducing toxin. Toxic myopathies may be classified as acute or chronic accordingly to the exposition time to a toxin. Main source of an exogenous induced toxic myopathy is chronic alcohol abuse. Alcohol excess induces acute and/or chronic neuropathy and myopathy, consequently muscle wasting and weakness occurs. Drug-induced myopathies are most frequently seen due to amplified utilization of corticosteroids or lipid lowering agents.

[Direct neuronal effects of statins]

Statins, i.e. HMG-CoA reductase inhibitors, reduce the risk of stroke and may have therapeutic potential for other neurologic diseases, including multiple sclerosis and Alzheimer's disease. In addition to lowering cholesterol levels, statins exert a number of cholesterol-independent (pleiotropic) effects. While endothelial, anti-thrombotic, anti-inflammatory, and immunomodulatory, i.e. peripheral, effects of statins are well known, little is known about the direct effects on neurons. This may be of clinical relevance because some statins are able to cross the blood-brain barrier. Recent experimental studies demonstrate that statins reduce the activity of neuronal glutamate receptors and protect neurons from excitotoxic insults. At higher doses, however, statins may also inhibit neurite sprouting and even induce neuronal apoptosis.