First report on phytochemical investigation, antioxidant and antidiabetic activities of Helianthemum getulum.

A new flavonoid, 5,7,2',4',5'-pentahydroxyflavone 3-O-ß-D-galactopyranoside (12) and twelve known derivatives: an aryltetralin-lignan (3), seven flavonoids (4-5, 7-10, 13) and four phenolic acids (1-2, 6, 11) have been isolated from the aerial parts of Helianthemum getulum Pomel. (Cistaceae family) an endemic species to the septentrional Sahara that is being studied for the first time. Structure elucidation of the isolated compounds was established by means of spectroscopic methods especially NMR and Mass Spectrometry. In vitro antioxidant (DPPH, ABTS, GOR and CUPRAC assays) and antidiabetic (micro-dilution method) activities of the crude extract, fractions and isolated compounds were performed. The new flavonol (12) and Compounds (2, 3, 7, 9) were found to be the most active, some of them exhibiting better activity than the antioxidant standards. Compounds 7, 9 and 3 showed higher α-glucosidase inhibitory activity compared to standard acarbose (IC50= 2.70 ± 0.03 µM, 3.09 ± 0.03 µM, 37.28 ± 1.20 µM and 275.43 ± 1.59 µM, respectively).

Evaluation of the Antioxidant, Anti-Inflammatory and Cytoprotective Activities of Halophyte Extracts against Mycotoxin Intoxication.

Twelve halophyte species belonging to different families, widely represented along French Atlantic shoreline and commonly used in traditional medicine, were screened for protective activities against mycotoxins, in order to set out new promising sources of natural ingredients for feed applications. Selected halophytic species from diverse natural habitats were examined for their in vitro anti-mycotoxin activities, through viability evaluation of Madin-Darby Bovine Kidney (MDBK) and intestinal porcine enterocyte (IPEC-J2) cell lines. Besides, the in vitro antioxidant activities of plant extracts were assessed (total antioxidant and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging bioassays). Of the 12 species, Galium arenarium, Convolvulus soldanella and Eryngium campestre exhibited the most protective action on MDBK and IPEC-J2 cells against zearalenone (ZEN) or T2 toxin contamination (restoring about 75% of cell viability at 10 µg·mL-1) without inflammation response. They also had strong antioxidant capacities (Inhibitory concentration of 50% (IC50) < 100 µg·mL-1 for DPPH radical and total antioxidant capacity (TAC) of 100 to 200 mg Ascorbic Acid Equivalent (AAE)·g-1 Dry Weight), suggesting that cell protection against intoxication involves antioxidant action. A bio-guided study showed that fractions of G. arenarium extract protect MDBK cells against T2 or ZEN toxicity and several major compounds like chlorogenic acid and asperuloside could be involved in this protective effect. Overall, our results show that the halophytes G. arenarium, C. soldanella and E. campestre should be considered further as new sources of ingredients for livestock feed with protective action against mycotoxin intoxication.

Effects of Spirulina platensis on lipid peroxidation, antioxidant defenses, and tissue damage in kidney of alloxan-induced diabetic rats.

Chronic hyperglycemia in diabetes causes free radicals overproduction, which contributes to the development of diabetic nephropathy. In modern medicine, no satisfactory therapy is available to cure diabetes mellitus. In that context, we investigated the potential therapeutic action of spirulina-enriched diet on renal impairment and oxidative stress in diabetic rats. Diabetes was induced by a single subcutaneous injection of alloxan (120 mg·kg-1) in rats. Following alloxan treatment, male Wistar rats were fed daily with 5% spirulina-enriched diet or treated with insulin (0.5 IU·rat-1) for 3 weeks. Diabetes was associated with hyperglycemia, increase in renal oxidative parameters (lipid peroxidation, thiobarbituric-acid reactive substances, protein carbonyl and advanced oxidation protein products levels, changes in antioxidant enzyme activities), and nephropathology markers. The renal injury induced by alloxan was confirmed by histological study of the diabetic rat kidney. Treatment with spirulina or insulin significantly ameliorated renal dysfunction by reducing oxidative stress, while rats recovered normal kidney histology. Overall, this study indicates that spirulina is efficient in inhibiting hyperglycemia and oxidative stress induced by diabetes, and suggests that the administration of this alga may be helpful in the prevention of diabetic complications. This amelioration was even more pronounced than that caused by insulin injection.

Cytoprotective and antioxidant effects of the edible halophyte Sarcocornia perennis L. (swampfire) against lead-induced toxicity in renal cells.

Lead (Pb) exposure is considered as a risk factor responsible for renal impairment in humans. On the other hand, the halophyte Sarcocornia perennis is a fresh vegetable crop suitable for leafy vegetable production. This study was designed to evaluate the in vitro protective activity of S. perennis against lead-induced damages in HEK293 kidney cells. Morphological and biochemical indicators were used to assess cytotoxicity and oxidative damages caused by Pb treatment on the cells. Our results showed that lead induced (1) a decrease in cell viability (MTT), (2) cell distortion and cohesion loss, (3) superoxide anion production and lipid peroxidation. Conversely, addition of S. perennis extract to the lead-containing medium alleviated every above syndrome. Thus, cell survival was increased and the production of reactive oxygen species caused by Pb treatment was inhibited. Taken together, our study revealed that S. perennis has potent cytoprotective effect against Pb-induced toxicity in HEK 293 cell. Such action would proceed through the decrease in ROS levels and resulting oxidative stress, which suggests a potential interest of this halophyte in the treatment of oxidative-stress related diseases.