Olive Leaf Powder Modulate Insulin Production and Circulating Adipokines in Streptozotocin Induced Diabetic Rats.

Olives (Olea europaea) have natural phytochemical compounds that are of great importance for their potential beneficially health effects. This study aimed to evaluate the effects of olive leaf powder (OLP) on insulin production and circulating adipokines in streptozotocin-induced diabetic rats. Forty Wistar-albino male rats, weighing 200-225 g were divided into four groups (n = 10); group I: Normal healthy rats received balanced diet; group II: Diabetic control rats receiving balanced diet; group III: Diabetic rats receiving balanced diet + standard antidiabetic drugs (metformin, 600 mg/bw) and group four: Diabetic rats received diet supplemented with 2.0% OLP. The experiment was conducted for four weeks. Our results showed that the consumption of 2.0% OLP decreased serum glucose, triglycerides (TG), total cholesterol (TC), and low-density lipoprotein (LDL) levels, whereas serum high density lipoprotein (HDL) level was increased. OLP supplementation also inhibited the atherogenic index [AI; log (TG/HDL-C) and atherogenic coefficient (AC)] levels relative to those of the untreated diabetic group. Moreover, OLP increased serum adiponectin concentration, and decreased serum leptin concentration. Liver and kidney functions were also attenuated by OLP. This finding also implies that OLP can play an important role in the treatment and delay of diabetic complications.

Potential Role of L-Arginine and Vitamin E Against Bone Loss Induced by Nano-Zinc Oxide in Rats.

The purpose of this study was to illustrate the effects of zinc oxide nanoparticles (ZnO-NPs) administration on bone turnover and bone resorbing agents in rats and how L-arginine (L-arg) or vitamin E (vit E) co-administrations might affect them. Fasting rats were randomly divided into four groups (n = 10): G1-normal healthy animals; G2-ZnO-NPs-exposed rats (600 mg/kg-1/day-1); G3-ZnO-NPs-exposed rats co-administrated L-arg (200 mg/kg-1/day-1); G4-ZnO-NPs-exposed rats co-administrated vit E (200 mg/kg-1/day-1). The ingredients were orally administered daily. The body weight and food consumption of rats were recorded during the administration period and the experiment continued for three consecutive weeks. The results demonstrated that ZnO-NPs administration induced bone loss in rats as manifested by reduced activity of bone alkaline phosphatase (B-ALP) and increased level of C-terminal peptide type I collagen (CTx). The increase of inflammatory markers, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) by ZnO-NPs suggests that deleterious effects of ZnO-NPs on bone turnover were, in part, due to inflammation. Confirming to this suggestion, both L-arg and vit E reduced TNF-α and IL-6 levels and consequently decreased bone resorption as indicated by reduced serum CTx level. This study proved that ZnO-NPs can induce bone turnover, which may be reduced by L-arg or vit.E co-administration, partly by anti-inflammatory mechanism.

Potential Intervention of α- Lipoic Acid and Carnitine on Insulin Sensitivity and Anti-Inflammatory Cytokines Levels in Fructose-Fed Rats, a Model of Metabolic Syndrome.

The objective of this work was to evaluate the beneficial effect of α-lipoic acid (ALA) and L-carnitine (CAR) on insulin sensitivity and anti-inflammatory markers in animal model of metabolic syndrome (MS), high fructose (HF)-fed rats. Forty male rats were randomly divided into four groups (n = 10). Group 1(control rats, G1), animals were allowed to drink 0.2% gum acacia (GA, p.o) and were fed a modified diet containing 65% cornstarch. The remaining rats were induced MS by feeding the same diet + free access to 10% fructose (w/v) in 0.2% GA (HF, MS) for 4 weeks. After 4 weeks of HF feeding, the rats were further divided into three subgroups; G2: HF (MS) in 0.2% GA, G3: HF (MS)+CAR (200 mg/kg/day) in 0.2% GA and G4: HF (MS)+ALA (200 mg/kg/day) in 0.2% GA, respectively. All ingredients were administered orally by guava daily for four weeks. A significant increase in serum glucose, insulin and Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) levels was observed after four weeks of HF feeding compared to control rats. Administration of ALA and CAR reversed the increase of the mentioned parameters. In HF rats, the increase of serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels were significantly lowered, while the reduction of the serum high-density lipoprotein cholesterol (HDL-C) was alleviated after administration of CAR and ALA. The reduction of the serum adiponectin level was significantly increased after administration of CAR and ALA. These data suggested that CAR and/or ALA had a beneficial role in the prevention of MS associated with development of type 2 diabetes.

Alleviation of bone markers in rats induced nano-zinc oxide by qurecetin and α-lipolic acid.

The purpose of this study was to evaluate the potential protective effect of qurecetin (Qur) and α-lipolic acid (ALA) to modulate the perturbation of bone turnover which is induced by nano-zinc oxide (n-ZnO). Rats were fasted overnight and randomly divided into two groups: G1, normal healthy animals and the other rats were administered zinc oxide nanoparticles orally by guava in a dose of 600 mg/kg body weight/d for 5 sequential days in Wistar albino male rats. N-ZnO-exposed animals were randomly sub-divided into three groups: G2, n-ZnO-exposed animals; G3, n-ZnO-exposed animals co-treated with Qur (200 mg/kg daily); and G4, n-ZnO-exposed animals co-treated with ALA (200 mg/kg). Qur and ALA were administered orally by guava daily for three sequential weeks from the beginning of the experiment. The results revealed a significant reduction of nitiric oxide (NO) and serum level and comet assay in n-ZnO exposure rats after treatment of Qur and ALA. It was found the alteration of pro-inflammatory markers (tumor necrosis factor alpha; TNF-α, interleukin-6; IL-6 and C-reactive protein; CRP), bone alkaline phosphatase (B-ALP, bone formation marker), and C-terminal peptide type I collagen (CTx, bone resorption marker) levels compared with the normal group. Co-administration of Qur and ALA in n-ZnO-exposed rats significantly alleviated the mentioned alterations of biochemical parameters. These results suggest that Qur and ALA as antioxidant agents may be a candidate for preventive and treatment applications of impaired bone markers induced bone loss caused by nano-particles of metal oxide.

Vitamin D status and insulin resistance among young obese Saudi females.

OBJECTIVES: To evaluate the association of vitamin D level with insulin resistance, among healthy student's obese women, and to identify factors that may elucidate this association. METHODS: One hundred and forty-seven female students between the age group of 18 and 25 years were included in this cross-sectional study, and the related socio-demographic and anthropometric data were obtained. They were selected randomly from Aljouf University, Sakaka, Saudi Arabia between November 2013 and June 2014. Serum 25-hydroxy vitamin D (25[OH]D), glucose, insulin was measured and insulin resistance was calculated using the insulin resistance index (HOMA-IR). RESULTS: The results showed the percentage of 25[OH]D concentration in female students was 21.3% sufficient, 59.6% mild deficiency, and 19.3% moderate deficiency. The percentage of waist circumferences (WC) were 41.3% (>88 cm) and 58.7% (<88 cm), body mass index (BMI) was 13.6% (obese) and 31.8% (over weight), blood pressure (BP) was 65.7% (<130/85 mm Hg), and 33.2% (>130/85 mm Hg). Based on the cut-off point of 25[OH]D, 17.4% of females had 25[OH]D  deficiency, 27.3% insufficient, and 55.3% sufficient. When the  females were classified according to the BMI category, the serum 25[OH]D  concentrations for obese was the lowest value (54.6%) when compared with the overweight (31.8%) and normal weight (0.9%). 25[OH]D  was inversely associated with BMI, fat%, and HOMA-IR.  CONCLUSION: Our results suggest that vitamin D deficiency is prevalent in women of Saudi who are university students especially in those who are obese. Preventive interventions in order to reduce the tendency of deficiency among college students should focus on the awareness of the essentiality of vitamin D promotion of direct exposure to sunlight (vitamin D3) and consumption of vitamin D fortified food as a part of Saudi diets.

Unhealthy nutritional habits in university students are a risk factor for cardiovascular diseases.

OBJECTIVE: To evaluate the relationship between the nutritional habits of university students with health parameters related to cardiovascular risk. METHODS: Three hundred and twelve students (180 females and 132 males; mean age 21.1 +/- 2.8 years) attending King Saud University, Riyadh, KSA were randomly selected from the university register and invited to participate in the study during 2008-2009. Students who consented to participate completed a self-reported questionnaire including: nutritional screen, health habits, and lifestyle practice. Daily food consumption was recorded, and nutritional analysis was performed. Blood pressure (BP) was also measured. RESULTS: A quarter of students was found to be overweight (21%) or obese (6.5%). The percentage of overweight and obese male students was 23% and 7% compared with female students who were 19% overweight and 6% obese. There was a positive correlation between fat consumption and BMI as well as BP in both genders, between economical status and BMI (p=0.05), and between salty food and BP (p=0.05). There was a negative correlation between consumption of fiber, grains, vegetables, fruits, beans, and BMI as well as BP in both genders (p=0.05). CONCLUSION: Our findings suggest that lifestyle modification is important especially in young age groups. The preventive interventions should focus not only on obesity, but also on related diseases. There is a need for strategies and coordinated efforts to reduce the tendency of overweight and obesity among college students.

Manipulation of flaxseed inhibits tumor necrosis factor-alpha and interleukin-6 production in ovarian-induced osteoporosis.

OBJECTIVE: To evaluate the potential effects of whole flaxseed (FS), and/or flax oil (FO) incorporation into the diet on the level of pro-inflammatory cytokines in ovariectomized (OVX) rats model of osteoporosis. METHODS: This study was performed in the Food Science & Agriculture Collage, King Saud University, Kingdom of Saudi Arabia from October to December 2009. Forty-eight, 3-month-old female Sprague-Dawley rats were randomly divided into 6 groups: Group 1 - sham + control diet; Group 2 - OVX rats + basal diet; Group 3 - OVX + 20% whole FS; Group 4 - OVX rats + 40% FS; Group 5 - OVX rats + 5% FO; Group 6 - OVX rats + 10% FO. All OVX rats underwent bilateral ovariectomy. The experiment was continued for 2 months. Serum bone alkaline phosphatase (B-ALP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), calcium (Ca), phosphorous (P), and magnesium (Mg) were measured. RESULTS: A significant increase of serum IL-6 and TNF-alpha concentrations were observed between OVX rats when compared with Group 1, while there was no significant difference in the activity of B-ALP, serum Ca, P, and Mg among all groups. A remarkable significant decrease of serum levels of IL-6 and TNF-alpha was observed in the group of rats that were fed with FS (Groups 3 and 4) and FO (Groups 5 and 6). CONCLUSION: This study suggests that FS and FO might be useful in the prevention of estrogen-deficiency induced osteoporosis via decreasing osteoclastogenesis. Further studies are needed to demonstrate their efficacy in humans by using bioactive components of FS, and to clarify their mechanism of action.