Reduction in FSH Throughout the Menstrual Cycle After Omega-3 Fatty Acid Supplementation in Young Normal Weight but not Obese Women.

Dietary fish oil restores ovarian function in subfertile rats, which is thought to be associated with decreased transcription of follicle-stimulating hormone (FSH) ß-subunit. We have previously demonstrated a reduction in early follicular serum FSH levels in normal weight but not obese women after treatment with omega-3 polyunsaturated fatty acids (PUFA). Herein, we report the effect of supplementation with omega-3 PUFA on urinary reproductive hormones across the whole menstrual cycle. This interventional study included 17 eumenorrheic women, aged 24-41 years. One month of daily morning urine was collected before and after 1 month of omega-3 PUFA supplementation with 4 g of eicosapentaenoic acid and docosahexaenoic acid daily. Measurements included urinary FSH, luteinizing hormone (LH) and estrogen and progesterone metabolites, plasma fatty acid composition, and markers of endoplasmic reticulum stress. Compliance with dietary supplementation was verified by significantly reduced ratios of omega-6 to omega-3 PUFA for all subjects after treatment (P < .01). After 1 month of omega-3 PUFA supplementation, urinary FSH was significantly decreased in normal weight, but not obese women, in both follicular and luteal phases (-28.4% and -12.6%, respectively, both P = .04). No significant changes were seen in LH or sex steroids for either weight group. The selective and specific decrease in FSH suggests that omega-3 PUFA supplementation merits further investigation in normal weight women with decreased fertility and/or diminished ovarian reserve.

Honey Bee Viruses in Wild Bees: Viral Prevalence, Loads, and Experimental Inoculation.

Evidence of inter-species pathogen transmission from managed to wild bees has sparked concern that emerging diseases could be causing or exacerbating wild bee declines. While some pathogens, like RNA viruses, have been found in pollen and wild bees, the threat these viruses pose to wild bees is largely unknown. Here, we tested 169 bees, representing 4 families and 8 genera, for five common honey bee (Apis mellifera) viruses, finding that more than 80% of wild bees harbored at least one virus. We also quantified virus titers in these bees, providing, for the first time, an assessment of viral load in a broad spectrum of wild bees. Although virus detection was very common, virus levels in the wild bees were minimal-similar to or lower than foraging honey bees and substantially lower than honey bees collected from hives. Furthermore, when we experimentally inoculated adults of two different bee species (Megachile rotundata and Colletes inaequalis) with a mixture of common viruses that is lethal to honey bees, we saw no effect on short term survival. Overall, we found that honey bee RNA viruses can be commonly detected at low levels in many wild bee species, but we found no evidence that these pathogens cause elevated short-term mortality effects. However, more work on these viruses is greatly needed to assess effects on additional bee species and life stages.

The Effect of Omega-3 Docosahexaenoic Acid Supplementation on Gestational Length: Randomized Trial of Supplementation Compared to Nutrition Education for Increasing n-3 Intake from Foods.

OBJECTIVE: DHA supplementation was compared to nutrition education to increase DHA consumption from fish and DHA fortified foods. DESIGN: This two-part intervention included a randomized double-blind placebo controlled DHA supplementation arm and a nutrition education arm designed to increase intake of DHA from dietary sources by 300 mg per day. SETTING: Denver Health Hospitals and Clinics, Denver, Colorado, USA. POPULATION: 871 pregnant women aged 18-40 were recruited between 16 and 20 weeks of gestation of whom 564 completed the study and complete delivery data was available in 505 women and infants. METHODS: Subjects received either 300 or 600 mg DHA or olive oil placebo or nutrition education. MAIN OUTCOME VARIABLE: Gestational length. RESULTS: Gestational length was significantly increased by 4.0-4.5 days in women supplemented with 600 mg DHA per day or provided with nutrition education. Each 1% increase in RBC DHA at delivery was associated with a 1.6-day increase in gestational length. No significant effects on birth weight, birth length, or head circumference were demonstrated. The rate of early preterm birth (1.7%) in those supplemented with DHA (combined 300 and 600 mg/day) was significantly lower than in controls. CONCLUSION: Nutrition education or supplementation with DHA can be effective in increasing gestational length.

Biodiversity, photosynthetic mode, and ecosystem services differ between native and novel ecosystems.

Human activities have caused non-native plant species with novel ecological interactions to persist on landscapes, and it remains controversial whether these species alter multiple aspects of communities and ecosystems. We tested whether native and exotic grasslands differ in species diversity, ecosystem services, and an important aspect of functional diversity (C3:C4 proportions) by sampling 42 sites along a latitudinal gradient and conducting a controlled experiment. Exotic-dominated grasslands had drastically lower plant diversity and slightly higher tissue N concentrations and forage quality compared to native-dominated sites. Exotic sites were strongly dominated by C4 species at southern and C3 species at northern latitudes with a sharp transition at 36-38°, whereas native sites contained C3:C4 mixtures. Large differences in C3:C4 proportions and temporal niche partitioning were found between native and exotic mixtures in the experiment, implying that differences in C3:C4 proportions along the latitudinal gradient are caused partially by species themselves. Our results indicate that the replacement of native- by exotic-dominated grasslands has created a management tradeoff (high diversity versus high levels of certain ecosystem services) and that models of global change impacts and C3/C4 distribution should consider effects of exotic species.

Fish oil decreases matrix metalloproteinases in knee synovia of dogs with inflammatory joint disease.

This study was designed to determine whether dietary fish oil affects the expression and activity of matrix metalloproteinases (MMP), tissue inhibitors of MMP-2 (TIMP-2) and urokinase plasminogen activator (uPA) in synovial fluid from dogs with spontaneously occurring stifle (knee) instability in a single hind limb resulting from acute cranial cruciate ligament (CCL) injury. Two groups of 12 dogs were fed diets from 1 week prior to surgery on the affected knee to 56 days post-surgery. The fish oil and control diets provided 90 and 4.5 mg, respectively, of combined eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)/kg body weight per day. Plasma and synovial fluid, from both surgical and nonsurgical knee joints, were obtained at start of the diet (-7), surgery day (0) and 7, 14, 28 and 56 days post-surgery. Plasma total EPA and DHA were significantly increased, and plasma total arachidonic acid (AA) was significantly decreased by the fish oil diet. In synovial fluid from the nonsurgical knee, fish oil treatment significantly decreased proMMP-2 expression at Days 7 and 14, and proMMP-9 expression at Day 56, and uPA activity at 28 days and significantly increased TIMP-2 expression at Days 7 and 28. There were no differences in MMP expression or activity, TIMP-2 expression and uPA activity in the surgical joint synovial fluid at any time throughout the study. These results suggest that dietary fish oil may exert beneficial effects on synovial fluid MMP and TIMP-2 equilibrium in the uninjured stifle of dogs with unilateral CCL injury.

Dietary docosahexaenoic acid alters pregnant rat reproductive tissue prostaglandin and matrix metalloproteinase production.

Shortened gestation is a major cause of infant mortality and morbidity. Evidence from both human and animal studies suggests that essential fatty acids of the n-6 and n-3 series play important and modifiable roles in gestational duration. We examined the influence of linolenic acid (LnA) vs. docosahexaenoic acid (DHA) on rat reproductive tissue prostaglandin (PG) and matrix metalloproteinase (MMP) indices of gestational duration. By varying the oil source of the diet, AIN-93G diets were constructed to provide either 0.7 energy % (en%) LnA, the current US intake of n-3 fatty acids, or 0.7 en% DHA. In addition, enhanced levels of 2.0 en% LnA or 2.0 e% DHA diets were also constructed. All diets contained approximately 6.0 en% linoleic acid (LA), the current US intake of LA. Four groups of 10 female rats were time-mated and fed the respective diets from conception through Day 20 of gestation. Day 20 uterus and placenta DHA were significantly increased by 160-180% by the 0.7 en% DHA diet, and by 250-350% by the 2.0 en% DHA diets in comparison to 0.7 en% LnA diet. DHA diets also significantly reduced uterus and placenta arachidonic acid content. Day 20 placenta and uterus PGE(2) and placenta PGF(2alpha) production rates were significantly reduced by 27-47% in the 0.7 en% DHA group in comparison to 0.7 en% LnA. Increasing LnA to 2.0 en% was without effect. Providing DHA at the enhanced 2.0 en% did not significantly enhance the suppression of PG production. Placenta active MMP-2 and active MMP-9 (gelatinase) production was suppressed significantly by 30-43% in the 0.7 en% DHA group in comparison to the 0.7 en% LnA group, and 2.0 en% DHA did not enhance this suppression. Placenta collagenase activity comprising the sum of MMP-1, MMP-8 and MMP-13 was also suppressed by 60% in the 0.7 en% DHA diet group with no additional effect with 2.0 en% DHA provision. These results suggest that substituting DHA for LnA even at the current US n-3 fatty acid intake of 0.7 en% is effective in suppressing indices of premature delivery and shortened gestation. Increasing LnA intake by 3-fold to 2.0 en% is not effective. The form of dietary n-3 fatty acid, DHA vs. LnA, appears to be more important than the amount.