Protection of Liver Functions and Improvement of Kidney Functions by Twelve Weeks Consumption of Cuban Policosanol (Raydel®) with a Decrease of Glycated Hemoglobin and Blood Pressure from a Randomized, Placebo-Controlled, and Double-Blinded Study with Healthy and Middle-Aged Japanese Participants.

Policosanol consumption has been associated with treating blood pressure and dyslipidemia by increasing the level of high-density lipoproteins-cholesterol (HDL-C) and HDL functionality. Although policosanol supplementation also ameliorated liver function in animal models, it has not been reported in a human clinical study, particularly with a 20 mg doage of policosanol. In the current study, twelve-week consumption of Cuban policosanol (Raydel®) significantly enhanced the hepatic functions, showing remarkable decreases in hepatic enzymes, blood urea nitrogen, and glycated hemoglobin. From the human trial with Japanese participants, the policosanol group (n = 26, male 13/female 13) showed a remarkable decrease in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) from baseline up to 21% (p = 0.041) and 8.7% (p = 0.017), respectively. In contrast, the placebo group (n = 26, male 13/female 13) showed almost no change or slight elevation. The policosanol group showed a 16% decrease in γ-glutamyl transferase (γ-GTP) at week 12 from the baseline (p = 0.015), while the placebo group showed a 1.2% increase. The policosanol group exhibited significantly lower serum alkaline phosphatase (ALP) levels at week 8 (p = 0.012), week 12 (p = 0.012), and after 4-weeks (p = 0.006) compared to those of the placebo group. After 12 weeks of policosanol consumption, the ferric ion reduction ability and paraoxonase of serum were elevated by 37% (p < 0.001) and 29% (p = 0.004) higher than week 0, while placebo consumption showed no notable changes. Interestingly, glycated hemoglobin (HbA1c) in serum was lowered significantly in the policosanol group 4 weeks after consumption, which was approximately 2.1% (p = 0.004) lower than the placebo group. In addition, blood urea nitrogen (BUN) and uric acid levels were significantly lower in the policosanol group after 4 weeks: 14% lower (p = 0.002) and 4% lower (p = 0.048) than those of the placebo group, respectively. Repeated measures of ANOVA showed that the policosanol group had remarkable decreases in AST (p = 0.041), ALT (p = 0.008), γ-GTP (p = 0.016), ALP (p = 0.003), HbA1c (p = 0.010), BUN (p = 0.030), and SBP (p = 0.011) from the changes in the placebo group in point of time and group interaction. In conclusion, 12 weeks of 20 mg consumption of policosanol significantly enhanced hepatic protection by lowering the serum AST, ALT, ALP, and γ-GTP via a decrease in glycated hemoglobin, uric acid, and BUN with an elevation of serum antioxidant abilities. These results suggest that improvements in blood pressure by consumption of 20 mg of policosanol (Raydel®) were accompanied by protection of liver function and enhanced kidney function.

Antiglycation potential and antioxidant activity of genipap (Genipa americana L.) in oxidative stress mediated by hydrogen peroxide on cell culture.

Genipa americana L. is a plant widely used by folk medicine for the prevention and as an aid in the treatment of various diseases. In this work, we evaluated the anti-glycant and antioxidant activities of genipap fruit juice, as well as the influence of different temperatures (-6 °C and -80 °C) on the preservation of phenolic compounds. Purified extract from G. americana showed anti-glycant activity reducing the formation of fructosamine by up to 53% and recovered viability of cells under oxidative stress induced by H2O2. HPLC/UV-Vis analysis identified cinnamic acid as a bioactive substance and possibly responsible for the biological activities described above. Taken together, these results indicate that G. americana is a rich source of cinnamic acid with appreciable antioxidant and anti-glycant potential.

The Protective Effect of Brazilian Propolis against Glycation Stress in Mouse Skeletal Muscle.

We investigated the protective effect of Brazilian propolis, a natural resinous substance produced by honeybees, against glycation stress in mouse skeletal muscles. Mice were divided into four groups: (1) Normal diet + drinking water, (2) Brazilian propolis (0.1%)-containing diet + drinking water, (3) normal diet + methylglyoxal (MGO) (0.1%)-containing drinking water, and (4) Brazilian propolis (0.1%)-containing diet + MGO (0.1%)-containing drinking water. MGO treatment for 20 weeks reduced the weight of the extensor digitorum longus (EDL) muscle and tended to be in the soleus muscle. Ingestion of Brazilian propolis showed no effect on this change in EDL muscles but tended to increase the weight of the soleus muscles regardless of MGO treatment. In EDL muscles, Brazilian propolis ingestion suppressed the accumulation of MGO-derived advanced glycation end products (AGEs) in MGO-treated mice. The activity of glyoxalase 1 was not affected by MGO, but was enhanced by Brazilian propolis in EDL muscles. MGO treatment increased mRNA expression of inflammation-related molecules, interleukin (IL)-1ß, IL-6, and toll-like receptor 4 (TLR4). Brazilian propolis ingestion suppressed these increases. MGO and/or propolis exerted no effect on the accumulation of AGEs, glyoxalase 1 activity, and inflammatory responses in soleus muscles. These results suggest that Brazilian propolis exerts a protective effect against glycation stress by inhibiting the accumulation of AGEs, promoting MGO detoxification, and reducing proinflammatory responses in the skeletal muscle. However, these anti-glycation effects does not lead to prevent glycation-induced muscle mass reduction.

Dereplication by HPLC-DAD-ESI-MS/MS and Screening for Biological Activities of Byrsonima Species (Malpighiaceae).

INTRODUCTION: Byrsonima species have been used in the treatment of gastrointestinal and gynecological inflammations, skin infections and snakebites. Based on their biological activities, it is important to study other organisms from this genus and to identify their metabolites. OBJECTIVES: To determine the metabolic fingerprinting of methanol and ethyl acetate extracts of four Byrsonima species (B. intermedia, B. coccolobifolia, B. verbascifolia and B. sericea) by HPLC-DAD-ESI-MS/MS and evaluate their in vitro antioxidant, anti-glycation, anti-inflammatory and cytotoxic activities. MATERIALS AND METHODS: Antioxidant activity was determined by DPPH˙, ABTS˙+ and ROO˙ scavenging assays. Anti-glycation activity was evaluated by the ability to inhibit the formation of advanced glycation endproducts (AGEs). Anti-inflammatory activity was evaluated using a murine macrophage cell line (RAW 264-7) in the presence of lipopolysaccharide (LPS). Tumour necrosis factor alpha (TNF-α) and nitrite (NO2- ) production were measured by ELISA and the Griess reaction, respectively. The compounds present in the extracts were tentatively identified by HPLC-DAD-ESI-MS/MS. RESULTS: The evaluation of the biological activities showed the potential of the extracts. The activities were assigned to the presence of glycoside flavonoids mainly derived from quercetin, quinic acid derivatives, gallic acid derivatives, galloylquinic acids and proanthocyanidins. Two isomers of sinapic acid-O-hexoside were described for the first time in a Byrsonima species. CONCLUSION: This research contributes to the study of the genus, it is the first report of the chemical composition of B. sericea and demonstrates the importance of the dereplication process, allowing the identification of known compounds without time-consuming procedures. Copyright © 2017 John Wiley & Sons, Ltd.

Antioxidant activity and protective role on protein glycation of synthetic aminocoumarins

Background: Synthesized aminocoumarins are heterocyclic compounds possessing potential for the treatment of insulin-dependent diabetes mellitus with unexplored anti-glycative action. Results: In this study 4-aminocoumarin derivatives (4-ACDs) were evaluated in vitro for antiglycation (AG) activities by using the human serum albumin (HSA)/glucose system, for 8 weeks of incubation. The glycation and conformational alteration of HSA in the presence of the tested compounds were evaluated by Congo red assay, fluorescence and circular dichroism spectroscopy. The antioxidant (AO) capacity were also tested by four different assays including: DPPH (2,2'-diphenyl-1-picrylhydrazyl radical), ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulphonate) diammonium salt), FRAP (ferric reducing antioxidant power) and β-carotene-linoleic acid assay. The tested compounds showed AG and AO effects. The intensity of the accomplished AO potential is related to the type of the used assay. Significant alterations in the secondary (monitored by CD spectropolarimetry) and tertiary structure (assessed by spectrofluorimetry) of HSA upon glycation were mitigated by the 4-ACDs, suggesting their suppressive role in the late stage (post-Amadori) of the HSA glycation. Conclusions: By the analogues, in vitro ascertained AO and AG properties of 4-ACD may be recognized as rationale for their protective role against oxidative changes of proteins, thereby precluding diabetic complications in humans.

Antioxidant activities of Juniperus foetidissima essential oils against several oxidative systems

The present study aimed to evaluate the antioxidant activity of essential oils obtained from branchlets of male and female trees as well as fruits of Juniperus foetidissima Willd., Cupressaceae, from Iran. For this purpose, essential oils of J. foetidissima were phytochemically analyzed and different concentrations of them were tested in five oxidative systems: 1) low-density lipoprotein oxidation; 2) linoleic acid peroxidation; 3) red blood cell hemolysis; 4) hemoglobin glycation; and 5) insulin glycation assays. In all employed systems, antioxidant effects were observed from the three tested oils though in varying degrees. The most promising activities of the oils were observed against hemoglobin and insulin glycation. Antioxidant activities of the oils did not appear to be dose-dependent. In addition, no consistent superiority in antioxidant effects was observed from a single oil in different assays. In view of the current results, J. foetidissima branchlet and fruit oils could be regarded as effective natural products with anti-glycation activity.