This randomized double-blind and controlled single-center clinical trial was designed to evaluate the effect of a 6-week intake of a probiotic product (1 capsule/day) vs. a placebo on an oxidative stress model of physical exercise (high intensity and duration) in male cyclists (probiotic group, n = 22; placebo, n = 21). This probiotic included three lyophilized strains (Bifidobacterium longum CECT 7347, Lactobacillus casei CECT 9104, and Lactobacillus rhamnosus CECT 8361). Study variables were urinary isoprostane, serum malondialdehyde (MDA), serum oxidized low-density lipoprotein (Ox-LDL), urinary 8-hydroxy-2′-deoxiguanosine (8-OHdG), serum protein carbonyl, serum glutathione peroxidase (GPx), and serum superoxide dismutase (SOD). At 6 weeks, as compared with baseline, significant differences in 8-OHdG (Δ mean difference −10.9 (95% CI −14.5 to −7.3); p < 0.001), MDA (Δ mean difference −207.6 (95% CI −349.1 to −66.1; p < 0.05), and Ox-LDL (Δ mean difference −122.5 (95% CI −240 to −4.5); p < 0.05) were found in the probiotic group only. Serum GPx did not increase in the probiotic group, whereas the mean difference was significant in the placebo group (477.8 (95% CI 112.5 to 843.2); p < 0.05). These findings suggest an antioxidant effect of this probiotic on underlying interacting oxidative stress mechanisms and their modulation in healthy subjects. The study was registered in ClinicalTrials.gov (NCT03798821).

A single-center, randomized, double-blind controlled trial was conducted to assess the efficacy of a food supplement based on a combination of grapefruit, bitter orange, and olive extracts administered for eight weeks (n = 51) versus placebo (n = 45) on reduction of cardiovascular risk in healthy volunteers. Study variables included flow-mediated vasodilation (FMD), blood pressure (BP), lipid profile, thrombotic status, oxidative stress biomarkers, inflammation-related biomarkers, anthropometric variables, quality of life, and physical activity. The per-protocol data set was analyzed. In the active product group, there were statistically significant within-group differences at eight weeks as compared with baseline in FMD, systolic and diastolic BP, total cholesterol, LDL-C, LDL-oxidase, oxidized/reduced glutathione ratio, protein carbonyl, and IL-6. Significant between-group differences in these variables were also found. Significant changes in anthropometric variables and quality of life were not observed in the study groups. Changes in the level of physical activity were not recorded. Treatment with the active product was well tolerated. All these findings, taken together, support a beneficial effect of supplementation with a mixture of grapefruit, bitter orange fruits, and olive leaf extracts on underlying mechanisms that may interact each other to decrease the cardiovascular risk in healthy people.

Hypertension is an important factor of cardiovascular diseases and contributes to their negative consequences including mortality. The World Health Organization estimated that 54% of strokes and 47% of cases of ischemic heart illness are related to high blood pressure. Recently, Hibiscus sabdariffa (HS) and Lippia citriodora (LC) have attracted scientific interest, and they are recognized for their high content of polyphenols as these may prevent several disease factors, such as hypertension. The aim of the present study is to determine if supplementation with an HS-LC blend (MetabolAid®) may be effective for the treatment of type 1 hypertensive sedentary populations. A total of 80 type 1 hypertensive subjects of both sexes were included in the study and were treated with placebo or the HS-LC extract, and both groups were treated over 84 days. The blood pressure (diastolic, systolic, and pulse pressure) was measured throughout the day, for each of the days of the study duration and determined using Ambulatory Blood Pressure Monitoring (ABPM). Physical activity was determined throughout the study to ensure similar conditions related to exercise. The results showed the capacity for reducing the blood pressure parameters in the case of the HS-LC extract. The daily consumption of the HS-LC extract but not the placebo over 84 days was able to reduce the daytime parameters related to blood pressure. The most remarkable results were observed in the measurements performed during the daytime, especially in the systolic blood pressure showing statistically significant variation.

Osteoarthritis is a source of chronic pain and disability. Dietary supplements have been shown to be a more secure option than NSAIDS. Particularly, the eggshell membrane has demonstrated efficacy in relieving joint pain and stiffness. A clinical trial was designed in which three groups were assigned to two different doses of this supplement and compared to a placebo control group. The primary outcome variable was knee pain, which was assessed using a visual analogue scale. Secondary outcome variables were knee functional ability, quadriceps muscle strength (assessed by isometric and isokinetic trials), and quality of sleep. All groups showed a significant decrease in pain perception, although maximum values were obtained in the high-dose group. Isokinetic and isometric trials showed a significant increase in strength in the high-dose group. Eggshell membrane showed the potential to reduce pain and stiffness symptomatology. Here, for the first time, two quantitative variables (mobility and strength of knee joint) were used to accurately evaluate changes in the quality of life of subjects affected by knee joint pain. The results of this study indicate a dose-dependent response, which should be taken into account for later use in therapeutics to establish the correct dosage.

A randomized, double-blind, placebo-controlled study was conducted with the primary objective of assessing the effect of a natural extract of Sclerocarya birrea on glucose metabolism in subjects with prediabetes. The duration of the study was 90 days. Thirty-three subjects assigned to the experimental group (daily ingestion of 100 mg of the nutraceutical product) and 34 assigned to the placebo group completed the study. There were 36 men and 31 women with a mean age of 32.3 ± 14.1 years. In the area under the curve (AUC) of the oral glucose tolerance test (OGTT), statistically significant decreases in the experimental group at 40 and 90 days as compared with baseline were found, whereas significant changes in the placebo group were not observed. Within-group differences were statistically significant in favor of the experimental group for glucose peak at OGTT, serum insulin, insulin resistance markers, and flow-mediated dilation. Changes in lipid and anthropometric parameters were not observed, although there was a trend for lower cholesterol levels and a decrease in body weight in the experimental group. Decreases in systolic blood pressure were also higher among subjects in the experimental group. This exploratory study confirms the antidiabetic activity of Sclerocarya birrea in prediabetes. Further studies using better measurements of beta-cell function are needed to clarify the underlying mechanisms of the hypoglycemic effect of this natural compound.

The aim of the study was to assess whether oral intake of a nutraceutical product (Citrolive™) could determine changes in low-density lipoprotein (LDL) oxidation and other parameters of lipid metabolism and plasma atherogenic capacity. Citrolive™ is a commercial extract obtained from the combination of citrus fruit flavonoids and olive leaf extracts. Twenty-three untreated subjects (69.6% males, 30.4% females, mean age 41.9 ± 9.4 years) with cardiovascular risk factors and a total cholesterol level >200 mg/dL and LDL cholesterol (LDL-C) > 130 mg/dL participated in a 3-month randomized double-blind controlled study. Participants in the intervention group (71.4% males, 28.6% females, mean age 42.7 ± 9.7 years) consumed Citrolive™ (500 mg, two capsules/day), and controls (66.7% males, 33.3% females, mean age 40.6 ± 9.4 years) received a matched placebo. At 3 months, oxidized LDL (ox-LDL) decreased significantly in the intervention group from 93.8 ± 19.1 U/L to 62.8 ± 28.7 U/L (p < 0.05), whereas the control group increased from 98.2 ± 23.5 U/L to 105.7 ± 21.9 U/L (p = 0.1). Between-group differences were also significant (p < 0.05). Similar findings in the ox-LDL/LDL-C ratio were observed. Serum paraoxonase activity (PON1) increased significantly in the intervention group from 64.5 ± 15.6 U/L to 78.7 ± 28.8 U/L (p < 0.05) but remained unchanged in controls. Consumption of Citrolive™ for 3 months in treatment-naïve subjects with moderate risk of atherosclerosis was associated with a reduction in oxidized LDL-C and LDL-oxidase/LDL-C ratio as compared to controls.