Mevastatin in colon cancer by spectroscopic and microscopic methods - Raman imaging and AFM studies

One of the most important areas of medical science is oncology, which is responsible for both the diagnostics and treatment of cancer diseases. Simultaneously one of the main challenges of oncology is the development of modern drugs effective in the fight against cancer. Statins are a group of biologically active compounds with the activity of 3-hydroxy-3-methyl glutaryl-CoA reductase inhibitors, an enzyme catalyzing the reduction of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) to mevalonic acid. By acting on this enzyme, statins inhibit the endogenous cholesterol synthesis which in turn causes the reduction of its systemic concentrations. However, in vitro and in vivo studies confirm also the cytostatic and cytotoxic effects of statins against various types of cancer cells including colon cancer. In the presented studies the influence of mevastatin on cancerous colon cells CaCo-2 by Raman spectroscopy and imaging is discussed and compared with biochemistry characteristic for normal colon cells CCD-18Co. Based on vibrational features of colon cells: normal cells CCD-18Co, cancerous cells CaCo-2 and cancerous cells CaCo-2 treated by mevastatin in different concentrations and incubation times we have confirmed the influence of this statin on biochemistry composition of cancerous human colon cells. Moreover, the spectroscopic results for colon normal cells and cancerous cells based on data typical for nucleic acids, proteins, lipids have been compared. The cytotoxisity of mevastatin was determined by using XTT tests.

Mevastatin promotes neuronal survival against Aβ-induced neurotoxicity through AMPK activation

Statins or HMG-CoA reductase inhibitors have been shown to be effective at lowering cholesterol levels, and the application of these molecules has gradually emerged as an attractive therapeutic strategy for neurodegenerative diseases. Epidemiological studies suggest that statin use is associated with a decreased incidence of Alzheimer's disease (AD). Thus, statins may play a beneficial role in reducing amyloid β (Aβ) toxicity, the most relevant pathological feature and pathogenesis of AD. However, the precise mechanisms involved in statin-inhibited Aβ toxicity remain unclear. In the present study, we report that mevastatin significantly protects against Aβ-induced neurotoxicity in SK-N-MC neuronal cells by restoring impaired insulin signaling. This protection appears to be associated with the activation of AMP-activated protein kinase (AMPK), which has long been known to increase insulin sensitivity. Our results also indicate that high levels of cholesterol likely underlie Aβ-induced neurotoxicity and that activation of AMPK by mevastatin alleviates insulin resistance. Signaling through the insulin receptor substrate-1/Akt pathway appears to lead to cell survival. These findings demonstrate that mevastatin plays a potential therapeutic role in targeting Aβ-mediated neurotoxicity. The molecule presents a novel therapeutic strategy for further studies in AD prevention and therapeutics.

Fermentative production and optimization of mevastatin in submerged fermentation using Aspergillus terreus

The main objective of the study is to enhance the mevastatin production using Plackett–Burman (PB) and central composite design (CCD) by Aspergillus terreus in submerged fermentation (SmF). Eight nutrients were chosen for a PB design with 12 experimental runs. A maximum mevastatin production of 170.4 mg L⁻¹ was obtained in PB design. Response surface methodology (RSM) is a sequential procedure with an initial objective to lead the experimenter rapidly and efficiently along a path of improvement toward the general vicinity of the optimum. The individual and interactive effects of these variables were studied by conducting the fermentation run at randomly selected and different levels of all five factors. Experiments were conducted to optimize the medium constituents like glycerol, CuCl₂·2H₂O, FeSO₄·7H₂O, KH₂PO₄ and MgSO₄·7H₂O. At the optimum condition, a maximum mevastatin production of 701 mg L⁻¹ was obtained.

Screening of nutrient parameters for mevastatin production by Penicillium citrinum MTCC 1256 under submerged fermentation using the Plackett-Burman design

OBJECTIVE

Mevastain, an HMG-CoA reductase inhibitor produced by Penicillium citrinum. The Placket-Burman experimental design was used to identify the important nutrients influencing the production of mevastatin by Penicillium citrinum MTCC 1256 under submerged fermentation.

MATERIALS AND METHODS

Nine nutritional parameters, such as, glucose, glycerol, arrowroot, oats, urea, peptone, yeast extract, MgSO(4).7H(2)O, and CaCl(2).2H(2)O were screened by Placket-Burman experimental design in 12 experimental run.

RESULTS

Nine nutritional parameters, glucose, glycerol, arrowroot, oats, urea, peptone, yeast extract, MgSO(4).7H(2)O, and CaCl(2).2H(2)O contributed with 0.8114%, 24.0390%, 2.2786%, 0.1491%, 0.5608%, 47.5029%, 6.8092 %, 4.0980%, 10.5823% respectively towards mevastatin production by Penicillium citrinum under submerged fermentation.

CONCLUSION

Among the nine nutrient components glycerol, peptone, yeast extract, MgSO(4).7H(2)0, and CaCl(2).2H(2)O contributed to a large extent, urea had little impact, while glucose, oats, and arrowroot contributed moderately on production of mevastatin.