The response to endotoxin in guinea pigs after intravenous black currant seed oil

Blackcurrant Anthocyanins Improve Blood Lipids and Biomarkers of Inflammation and Oxidative Stress in Healthy Women in Menopause Transition without Changing Body Composition

Recent cell and animal studies suggest the potential of blackcurrants (BCs; Ribes nigrum) as a dietary agent that may reduce the risk of cardiovascular disease (CVD) by improving dyslipidemia, oxidative stress, and inflammation. This study aimed to examine the effects of BC anthocyanin (ACN) extract supplementation on biomarkers of CVD risk in healthy adult women in menopause transition. The effects of BC ACN supplementation on body composition, fasting blood lipids and biomarkers of inflammation and oxidative stress were evaluated using anthropometric measures and blood samples collected from a pilot randomized controlled clinical trial in peri- and early postmenopausal women. Thirty-eight eligible peri- and early postmenopausal women aged 45-60 completed the entire trial, in which they were randomly assigned into one of three treatment groups: placebo (control group), 392 mg/day (low BC group), or 784 mg/day (high BC group) for six months. The significance of differences in outcomes was tested using repeated-measures ANOVA. Overall, following six-month BC consumption, significantly decreased triglyceride (TG) levels were observed between treatment groups (p < 0.05) in a dose-dependent manner. Plasma interleukin-1β (IL-1β) was significantly reduced in a dose and time dependent manner (p < 0.05). Significant decreases in thiobarbituric acid reactive substances (TBARS) levels were also observed between treatment groups (p < 0.05) in a dose-dependent manner. Six-month change in oxidized LDL was inversely correlated with changes in catalase (CAT) and total antioxidant capacity (TAC) (p < 0.05), while C-reactive protein (hs-CRP) change was positively correlated with changes in TG and IL-1β (p < 0.01). Together, these findings suggest that daily BC consumption for six months effectively improved dyslipidemia, inflammation, and lipid peroxidation, thus potentially mitigating the risk of postmenopausal CVD development in study participants. Future studies with larger sample sizes and at-risk populations are warranted to confirm these findings.

The Effects of Blackcurrant and Raspberry Consumption on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

A systematic review and meta-analysis were designed to summarize studies conducted on the effects of raspberry and blackcurrant consumption on blood pressure (BP). Eligible studies were detected by searching numerous five online databases including PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, until December 17, 2022. We pooled the mean difference and its 95% confidence interval (CI) by applying a random-effects model. Overall, the impact of raspberry and blackcurrant on BP was reported in ten randomized controlled trials (RCTs) (420 subjects). Pooled analysis of six clinical trials revealed that raspberry consumption has no significant reduction in systolic blood pressure (SBP) (weighted mean differences [WMDs], -1.42; 95% CI, -3.27 to 0.87; p = 0.224) and diastolic blood pressure (DBP) (WMD, -0.53; 95% CI, -1.77 to 0.71; p = 0.401), in comparison with placebo. Moreover, pooled analysis of four clinical trials indicated that blackcurrant consumption did not reduce SBP (WMD, -1.46; 95% CI, -6.62 to 3.7; p = 0.579), and DBP (WMD, -2.09; 95% CI, -4.38 to 0.20; p = 0.07). Raspberry and blackcurrant consumption elicited no significant reductions in BP. More accurate RCTs are required to clarify the impact of raspberry and blackcurrant intake on BP.

Anti-cancer properties and mechanisms of action of thymoquinone, the major active ingredient of Nigella sativa

Over the past two decades, studies have documented the wide-range anti-cancer effects of Nigella sativa, known as black seed or black cumin. Thymoquinone (TQ), its major active ingredient, has also been extensively studied and reported to possess potent anti-cancer properties. Herein, we provide a comprehensive review of the findings related to the anti-cancer activity of TQ. The review focuses on analyzing experimental studies performed using different in vitro and in vivo models to identify the anti-proliferative, pro-apoptotic, anti-oxidant, cytotoxic, anti-metastatic, and NK-dependent cytotoxic effects exerted by TQ. In addition, we pinpoint the molecular mechanisms underlying these effects and the signal transduction pathways implicated by TQ. Our analysis show that p53, NF-κB, PPARγ, STAT3, MAPK, and PI3K/AKT signaling pathways are among the most significant pathways through which TQ mediates its anti-cancer activity. Experimental findings and recent advances in the field highlight TQ as an effective therapeutic agent for the suppression of tumor development, growth and metastasis for a wide range of tumors.

Anthocyanin-Rich Blackcurrant Extract Attenuates Ovariectomy-Induced Bone Loss in Mice

Although several animal and cell studies have indicated that blackcurrant anthocyanins exert antioxidative and anti-inflammatory properties, which could potentially improve bone mass, the effect of blackcurrant on bone health has not been reported yet. Thus, this study was aimed to evaluate the effect of blackcurrant anthocyanins on bone mass in an estrogen deficiency mouse model. Fourteen-week-old C57BL/6J mice (n = 54) were ovariectomized or sham operated. The ovariectomized mice were divided into two groups, basal diet (OVX) or basal diet containing 1% anthocyanin-rich blackcurrant extract (OVX+BC), and sacrificed at 4, 8, and 12 weeks. Femoral bone mineral density (BMD) and trabecular bone volume by dual-energy X-ray absorptiometry and micro-computed tomography, respectively, and serum bone markers were measured. Ovariectomy significantly reduced BMD and trabecular bone volume at all time points (P < .05). Blackcurrant supplementation attenuated ovariectomy-induced bone loss measured by BMD and trabecular bone volume at 8 weeks (P = .055 and P = .057) and the effect was more pronounced at 12 weeks (P = .053 and P < .05). Ovariectomy and blackcurrant treatment did not alter serum biomarkers of bone formation and resorption. Bone marrow cells extracted from OVX mice significantly induced osteoclast-like (OCL) cell formation compared with cells from sham controls (P < .05). Blackcurrant treatment decreased the number of TRAP(+) OCL compared with OVX mice at 8 and 12 weeks (P < .05). Furthermore, blackcurrant supplementation reduced bone resorption activity when measured by resorption pit assay, compared with OVX group (P < .05). These results demonstrate that blackcurrant may be effective in mitigating osteoclast-induced postmenopausal bone loss.

Black currant anthocyanins normalized abnormal levels of serum concentrations of endothelin-1 in patients with glaucoma

PURPOSE

Our recent study, which involved a randomized, placebo-controlled, double-masked 24-month trial (Ophthalmologica 2012;228:26-35), revealed that oral administration of black currant anthocyanins (BCACs) slowed down the visual field deterioration and elevation of ocular blood flow of open-angle glaucoma (OAG). To elucidate the underlying mechanisms of these BCAC-induced effects, as possible factors affecting glaucomatous optic neuropathy, changes of serum endothelin-1 (ET-1), nitric oxide (NO), and antioxidative activities were examined in the present study.

METHODS

From among patients with OAG who participated in the randomized, placebo-controlled, double-masked trial, serum specimens were obtained from BCAC-treated (n=19) or placebo-treated (n=19) patients at baseline and every 6 months. Healthy volunteers (n=20) with age and gender matching the patients were used as a control. Serum ET-1 concentration, [NO2(-)] and [NO2(-) + NO3(-)] levels, advanced oxidation protein products (AOPP), and antioxidant activities were measured by using commercially available kits.

RESULTS

At the trial baseline, serum ET-1 concentrations were significantly lower in patients with OAG (BCACs, 3.18±1.06 pg/mL; placebo, 3.44±0.84 pg/mL) than those in healthy volunteers (4.38±1.03 pg/mL) (one-way analysis of variance and a Tukey's multiple comparison post hoc test, P<0.05). Upon administration of BCACs, serum ET-1 concentrations increased to the levels of those in healthy volunteers during the 24-month period. In contrast, those of placebo-treated patients remained at lower levels (3.82±1.14 pg/mL). While [NO2(-)] and [NO2(-)+NO3(-)] levels, AOPP, and antioxidative activities of patients from both the BCACs and placebo groups showed comparable levels to those of healthy subjects at baseline, no significant changes were observed during the observational period in either the BCAC or placebo groups.

CONCLUSIONS

Among the possible beneficial effects of BCACs toward visual field progression in patients with OAG, our present results suggest that BCACs caused normalization of serum ET-1 levels, and this may modulate ET-1-dependent regulation of the ocular blood hemodynamics.

Two-year randomized, placebo-controlled study of black currant anthocyanins on visual field in glaucoma

AIM

To examine the influence of the black currant anthocyanins (BCACs) on the disease progression of open-angle glaucoma (OAG), a randomized, placebo-controlled, double-masked trial was made in 38 patients with OAG treated by antiglaucoma drops.

METHODS

BCACs (50 mg/day, n = 19) or their placebos (n = 19) were orally administered once daily for a 24-month period. Systemic blood pressure, pulse rates, intraocular pressure (IOP), ocular blood circulation by laser-speckle flowgraphy, and Humphrey visual field mean deviation (MD) were measured during the 24-month period.

RESULTS

As a main outcome measurement, we evaluated the difference between the groups in MD deterioration in the eye with a better MD from the trial's baseline through 24 months. A statistically significant difference was observed between the treatment groups in mean change from baseline in MD 24 months after therapy (p = 0.039, unpaired t test). Upon administration of BCACs, the ocular blood flows during the 24-month observational period increased in comparison with placebo-treated patients. However, no significant changes were observed in systemic and ocular conditions including IOP during the 24-month period.

CONCLUSIONS

Our results suggest that oral administration of BCACs may be a safe and promising supplement for patients with OAG in addition to antiglaucoma medication.

Nigella sativa modulates splenocyte proliferation, Th1/Th2 cytokine profile, macrophage function and NK anti-tumor activity

AIM OF THE STUDY

Nigella sativa, also known as blackseed, has long been used in traditional medicine for treating various conditions related to the respiratory and gastrointestinal systems as well as different types of cancers. In this study, the potential immunomodulatory effects of Nigella sativa are investigated in light of splenocyte proliferation, macrophage function, and NK anti-tumor activity using BLAB/c and C57/BL6 primary cells.

MATERIALS AND METHODS

Splenocyte proliferation was assessed by [(3)H]-thymidine incorporation. Griess assay was performed to evaluate NO production by macrophages. ELISA was performed to measure the level of cytokines secreted by splenocytes and macrophages. NK cytotoxic activity against YAC-1 tumor cells was examined by JAM assay.

RESULTS

We demonstrate that the aqueous extract of Nigella sativa significantly enhances splenocyte proliferation in a dose-responsive manner. In addition, the aqueous extract of Nigella sativa favors the secretion of Th2, versus Th1, cytokines by splenocytes. The secretion of IL-6, TNFalpha, and NO; key pro-inflammatory mediators, by primary macrophages is significantly suppressed by the aqueous extract of Nigella sativa, indicating that Nigella sativa exerts anti-inflammatory effects in vitro. Finally, experimental evidence indicates that the aqueous extract of Nigella sativa significantly enhances NK cytotoxic activity against YAC-1 tumor cells, suggesting that the documented anti-tumor effects of Nigella sativa may be, at least in part, attributed to its ability to serve as a stimulant of NK anti-tumor activity.

CONCLUSIONS

Our data present Nigella sativa as a traditionally used herb with potent immunomodulatory, anti-inflammatory, and anti-tumor effects. We anticipate that Nigella sativa ingredients may be employed as effective therapeutic agents in the regulation of diverse immune reactions implicated in various conditions and diseases such as cancer.

Short-term blackcurrant extract consumption modulates exercise-induced oxidative stress and lipopolysaccharide-stimulated inflammatory responses

Exercise-induced oxidative stress is instrumental in achieving the health benefits from regular exercise. Therefore, inappropriate use of fruit-derived products (commonly applied as prophalytic antioxidants) may counteract the positive effects of exercise. Using human exercise and cellular models we found that 1) blackcurrant supplementation suppressed exercise-induced oxidative stress, e.g., plasma carbonyls (0.9 ± 0.1 vs. 0.6 ± 0.1 nmol/mg protein, placebo vs. blackcurrant), and 2) preincubation of THP-1 cells with an anthocyanin-rich blackcurrant extract inhibited LPS-stimulated cytokine secretion [TNF-α (16,453 ± 322 vs. 10,941 ± 82 pg/ml, control vs. extract, P < 0.05) and IL-6 (476 ± 14 vs. 326 ± 32 pg/ml, control vs. extract, P < 0.05)] and NF-κB activation. In addition to its antioxidant and anti-inflammatory properties, we found that postexercise plasma collected after blackcurrant supplementation enhanced the differential temporal LPS-stimulated inflammatory response in THP-1 cells, resulting in an early suppression of TNF-α (1,741 ± 32 vs. 1,312 ± 42 pg/ml, placebo vs. blackcurrant, P < 0.05) and IL-6 (44 ± 5 vs. 36 ± 3 pg/ml, placebo vs. blackcurrant, P < 0.05) secretion after 24 h. Furthermore, by using an oxidative stress cell model, we found that preincubation of THP-1 cells with hydrogen peroxide (H2O2) prior to extract exposure caused a greater suppression of LPS-stimulated cytokine secretion after 24 h, which was not evident when cells were simultaneously incubated with H2O2 and the extract. In summary, our findings support the concept that consumption of blackcurrant anthocyanins alleviate oxidative stress, and may, if given at the appropriate amount and time, complement the ability of exercise to enhance immune responsiveness to potential pathogens.

Immunomodulatory and therapeutic properties of the Nigella sativa L. seed

A larger number of medicinal plants and their purified constituents have been shown beneficial therapeutic potentials. Seeds of Nigella sativa, a dicotyledon of the Ranunculaceae family, have been employed for thousands of years as a spice and food preservative. The oil and seed constituents, in particular thymoquinine (TQ), have shown potential medicinal properties in traditional medicine. In view of the recent literature, this article lists and discusses different immunomodulatory and immunotherapeutic potentials for the crude oil of N. sativa seeds and its active ingredients. The published findings provide clear evidence that both the oil and its active ingredients, in particular TQ, possess reproducible anti-oxidant effects through enhancing the oxidant scavenger system, which as a consequence lead to antitoxic effects induced by several insults. The oil and TQ have shown also potent anti-inflammatory effects on several inflammation-based models including experimental encephalomyelitis, colitis, peritonitis, oedama, and arthritis through suppression of the inflammatory mediators prostaglandins and leukotriens. The oil and certain active ingredients showed beneficial immunomodulatory properties, augmenting the T cell- and natural killer cell-mediated immune responses. Most importantly, both the oil and its active ingredients expressed anti-microbial and anti-tumor properties toward different microbes and cancers. Coupling these beneficial effects with its use in folk medicine, N. sativa seed is a promising source for active ingredients that would be with potential therapeutic modalities in different clinical settings. The efficacy of the active ingredients, however, should be measured by the nature of the disease. Given their potent immunomodulatory effects, further studies are urgently required to explore bystander effects of TQ on the professional antigen presenting cells, including macrophages and dendritic cells, as well as its modulatory effects upon Th1- and Th2-mediated inflammatory immune diseases. Ultimately, results emerging from such studies will substantially improve the immunotherapeutic application of TQ in clinical settings.

Effect of dietary supplementation with black currant seed oil on the immune response of healthy elderly subjects

BACKGROUND

We have shown that the age-associated increase in prostaglandin E(2) production contributes to the decline in T cell-mediated function with age. Black currant seed oil (BCSO), rich in both gamma-linolenic (18:3n-6) and alpha-linolenic (18:3n-3) acids, has been shown to modulate membrane lipid composition and eicosanoid production.

OBJECTIVE

Our objectives were to 1) test whether dietary supplementation with BCSO can improve the immune response of healthy elderly subjects, and 2) determine whether the altered immune response is mediated by a change in the factors closely associated with T cell activation.

DESIGN

A randomized, double-blind, placebo-controlled (soybean oil) study was conducted to examine the effect of 2 mo of BCSO supplementation on the immune response of 40 healthy subjects aged >/=65 y. In vivo immune function was determined by delayed-type hypersensitivity skin response. Peripheral blood mononuclear cells (PBMCs) were tested for in vitro immune response.

RESULTS

In subjects supplemented with BCSO, the total diameter of induration at 24 h and individual responses to tetanus toxoid and Trichophyton mentagrophytes were significantly higher than their baseline values. The change in response to tetanus toxoid was significantly different from that of the placebo group. The BCSO group showed a significant increase in proliferative response of PBMCs to the T cell mitogen phytohemagglutinin that was not significantly different from that observed in the placebo group. BCSO had no effect on concanavalin A-induced mitogenic response, interleukin 2 and -1beta production, and PBMC membrane fluidity. Prostaglandin E(2) production was significantly reduced in the BCSO-supplemented group, and this change was significantly different from that of the placebo group.

CONCLUSION

BCSO has a moderate immune-enhancing effect attributable to its ability to reduce prostaglandin E(2) production.