Propolis is a complex mixture of natural sticky and resinous components produced by honeybees from living plant exudates. Globally, research has been dedicated to studying the biological properties and chemical composition of propolis from various geographical and climatic regions. However, the chemical data and biological properties of Mexican brown propolis are scant. The antioxidant activity of the ethanolic extract of propolis (EEP) sample collected in México and the isolated compounds is described. Cytotoxic activity was evaluated in a central nervous system and cervical cancer cell lines. Cytotoxicity of EEP was evaluated in a C6 cell line and cervical cancer (HeLa, SiHa, and CasKi) measured by the 3-(3,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium (MTT) assay. The antibacterial activity was tested using the minimum inhibitory concentration (MIC) assay. Twelve known compounds were isolated and identified by nuclear magnetic resonance spectroscopy (NMR). Additionally, forty volatile compounds were identified by means of headspace-solid phase microextraction with gas chromatography and mass spectrometry time of flight analysis (HS-SPME/GC-MS-TOF). The main volatile compounds detected include nonanal (18.82%), α-pinene (12.45%), neryl alcohol (10.13%), and α-pinene (8.04%). EEP showed an anti-proliferative effect on glioma cells better than temozolomide, also decreased proliferation and viability in cervical cancer cells, but its effectiveness was lower compared to cisplatin.
Docosahexaenoic acid (DHA) is an omega-3 (ω-3) long-chain polyunsaturated fatty acid (LCPUFA) relevant for brain function. It has largely been explored as a potential candidate to treat Alzheimer’s disease (AD). Clinical evidence favors a role for DHA in the improvement of cognition in very early stages of the AD. In response to stress or damage, DHA generates oxygenated derivatives called docosanoids that can activate the peroxisome proliferator-activated receptor γ (PPARγ). In conjunction with activated retinoid X receptors (RXR), PPARγ modulates inflammation, cell survival, and lipid metabolism. As an early event in AD, inflammation is associated with an excess of amyloid β peptide (Aβ) that contributes to neural insult. Glial cells are recognized to be actively involved during AD, and their dysfunction is associated with the early appearance of this pathology. These cells give support to neurons, remove amyloid β peptides from the brain, and modulate inflammation. Since DHA can modulate glial cell activity, the present work reviews the evidence about this modulation as well as the effect of docosanoids on neuroinflammation and in some AD models. The evidence supports PPARγ as a preferred target for gene modulation. The effective use of DHA and/or its derivatives in a subgroup of people at risk of developing AD is discussed.
1 January 2007 in American Journal of Physiology-Renal Physiology
Recent studies from our laboratory have shown that the mineralocorticoid receptor (MR) blockade with spironolactone (Sp) prevented renal dysfunction and reduced renal injury in both acute and chronic cyclosporine (CsA) nephrotoxicity. This study was designed to evaluate whether Sp administration reduces functional and structural renal damage associated in the setting of preexisting chronic CsA nephrotoxicity. Twenty eight male Wistar rats were fed a low-sodium diet. Fourteen received vehicle (V) and the others were treated with CsA (15 mg/kg sc). After 18 days one half of each group received Sp (20 mg/kg po) for the subsequent 18 days. Creatinine clearance, arteriolopathy, tubulointerstitial fibrosis, arteriolar thickening, glomerular diameter, apoptosis index and TGF-β, procaspase-3, and kidney injury molecule 1 (Kim-1) mRNA levels as well as Kim-1 shedding in urine were evaluated. Sp reduced the progression of renal dysfunction and tubulointerstitial fibrosis in preexisting chronic CsA nephrotoxicity. There was a significant reduction of arteriolar thickening in the CsA+Sp group that was associated with greater glomerular diameter and reduction of apoptosis index. These renoprotective effects were associated with reduction of TGF-β, procaspase-3, and Kim-1 mRNA levels as well as Kim-1 shedding into the urine. In conclusion, MR blockade with Sp prevented the progression of renal injury in preexisting chronic CsA nephropathy. These results suggest that Sp may reduce CsA-induced established nephrotoxicity in patients.