Effect of evening primrose oil and ω-3 polyunsaturated fatty acids on the cardiovascular risk of celecoxib in rats

Evening Primrose Oil Ameliorates Hyperleptinemia and Reproductive Hormone Disturbances in Obese Female Rats: Impact on Estrus Cyclicity

Obesity is a public health burden disturbing all body functions and reproductive hormones. As obesity increases among females, there will be a rising challenge to physicians in care from fertility problems. Evening primrose oil (EPR oil) contains essential fatty acids including omega-6 linoleic acid with strong anti-inflammatory activity. Since EPR oil has utility in alleviating dysmenorrhea, this study aimed to ascertain its modulatory effect on systemic inflammation, reproductive hormones and estrus cycle irregularity in female obese rats. Thirty-two female rats were distributed to 4 groups: (i) normal, (ii) dietary obese-control female rats, and (iii and iv) dietary obese female rats treated with EPR oil (5 or 10 g/kg). Rats were examined for estrus regularity by taking vaginal smears daily during the last 2 weeks of the experiment. Serum level of insulin, leptin, adiponectin, and inflammatory cytokines was measured. In addition, serum lipid profile, and liver enzyme activities were estimated. Adipose tissues were taken for histopathologic examination as well as determination of gene expression for leptin, leptin receptors, adiponectin, and visfatin. Obese rats exhibited significant weight gain (90.69 ± 8.9), irregular prolonged estrus cycles (83.33%), increased serum levels of insulin, leptin, prolactin and testosterone and decreased gonadotropin levels. EPR oil exhibited a curative effect on obesity-related irregularity in estrus cycle and ovarian pathology. The underlying molecular mechanism may be related to reduction of systemic inflammation, alleviating insulin resistance and modulation of adipokine expression. EPR oil may be considered as a promising therapeutic intervention against obesity-related female hormonal disturbances and estrus irregularity.

Evening primrose oil or forskolin ameliorates celecoxib-enhanced upregulation of tissue factor expression in mice subjected to lipopolysaccharide-induced endotoxemia

Celecoxib, a selective cyclooxygenase-2 inhibitor, produces thrombotic events in patients predisposed to cardiovascular risk factors. One theory reported an increase in endothelial expression of tissue factor (TF) as a predisposing factor. This work explored the effect of evening primrose oil (EPO), a source of prostaglandin E1, and forskolin (a cyclic adenosine monophosphate stimulator) against the prothrombotic effect of celecoxib in mice. Lipopolysaccharide mouse model of endotoxemia was used to induce an upregulation of TF activity. Male mice received celecoxib (25 mg/kg), celecoxib plus EPO, or celecoxib plus forskolin for 4 weeks and then subjected to a prothrombotic challenge in the form of an intraperitoneal injection of lipopolysaccharide. Results showed an increase in plasma TF activity, endothelial TF expression, and thrombin-antithrombin (TAT) but lower antithrombin III (ATIII) level in mice that received celecoxib in comparison to those that received the vehicle. Adding EPO or forskolin to celecoxib regimen significantly decreased the prothrombotic effect of celecoxib. A positive correlation (r = 0.8501) was found between TF activity and TAT. Co-administration of EPO or forskolin decreased the activity of TF and mitigated the prothrombotic effect of celecoxib. Therefore, these combinations may have the utility to abrogate the prothrombotic adverse effect of celecoxib in clinical setting.

Concentrated fish oil (Lovaza(R)) extends lifespan and attenuates kidney disease in lupus-prone short-lived (NZBxNZW)F1 mice

A growing number of reports indicate that anti-inflammatory actions of fish oil (FO) are beneficial against systemic lupus erythematosus (SLE). However, the majority of pre-clinical studies were performed using 5-20% FO, which is higher than the clinically relevant dose for lupus patients. The present study was performed in order to determine the effective low dose of FDA-approved concentrated FO (Lovaza®) compared to the commonly used FO-18/12 (18-Eicosapentaenoic acid [EPA]/12-Docosahexaenoic acid [DHA]). We examined the dose-dependent response of Lovaza® (1% and 4%) on an SLE mouse strain (NZBxNZW)F1 and compared the same with 1% and 4% placebo, as well as 4% FO-18/12, maintaining standard chow as the control. Results show for the first time that 1% Lovaza® extends maximal lifespan (517 d) and 4% Lovaza® significantly extends both the median (502 d) and maximal (600 d) life span of (NZBxNZW)F1 mice. In contrast, FO-18/12 extends only median lifespan (410 d) compared to standard chow diet (301 d). Additionally, 4% Lovaza® significantly decreased anti-dsDNA antibodies, reduced glomerulonephritis and attenuated lipopolysaccharide-induced pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) in splenocytes compared to placebo. 4% Lovaza® was also shown to reduce the expression of inflammatory cytokines, including IL-1β, IL-6 and TNF-α, while increasing renal anti-oxidant enzymes in comparison to placebo. Notably, NFκB activation and p65 nuclear translocation were lowered by 4% Lovaza® compared to placebo. These data indicate that 1% Lovaza® is beneficial, but 4% Lovaza® is more effective in suppressing glomerulonephritis and extending life span of SLE-prone short-lived mice, possibly via reducing inflammation signaling and modulating oxidative stress.

Procyanidins from evening primrose (Oenothera paradoxa) defatted seeds inhibit invasiveness of breast cancer cells and modulate the expression of selected genes involved in angiogenesis, metastasis, and apoptosis

There is a growing interest in plant polyphenols (including flavanols) that exhibit pleiotropic biological activities such as antiinflammatory, antioxidant, and anticancer effects. Here, we report for the first time the inhibition of MDA-MB-231 breast cancer cell viability and invasiveness by an evening primrose flavanol preparation (EPFP). We observed a decrease in MDA-MB-231 viability of 50% vs. a control after 72 h of incubation with EPFP at a concentration of 58 μM gallic acid equivalents (GAE) and an inhibition of their invasiveness of 65% vs. a control at 75 μM GAE after 48 h of incubation. EPFP caused a 10-fold reduction in matrix metalloproteinase-9 (MMP-9) activity at 100 μM GAE. Furthermore, through modulation of mRNA expression, EPFP reduced the expression levels of the following proteins: antiapoptotic Bcl-2, angiogenic vascular endothelial growth factor (VEGF), and 2 transcription factors (c-Jun, c-Fos). Moreover, analysis by flow cytometry revealed that EPFP induced apoptosis in MDA-MB-231 cells. In conclusion, our data shows that EPFP inhibits cell viability by increasing apoptosis and decreases cell invasiveness by decreasing angiogenesis.