Voss K A, Bacon C W, Norred W P, Chapin R E, Chamberlain W J, Plattner R D, Meredith F I
USDA, Richard B. Russell Agricultural Research Center, Athens, Georgia 30604-5677, USA.
Nat Toxins. 1996;4(1):24-33. doi: 10.1002/19960401nt4.
Fumonisins are mycotoxins produced by Fusarium moniliforme and other Fusarium species. They are commonly found in corn and corn-based foodstuffs. Fumonisins inhibit sphingolipid (SL) biosynthesis, alter cellular SL profiles, and thus may affect cell proliferation and differentiation, both of which are important processes for reproduction. However, there are few reports of the effects of F. moniliforme or fumonisins on mammalian reproduction or development. To study the reproductive effects of this fungus, diets formulated with culture material of toxic F. moniliforme strain MRC 826 (CM) to provide 0, 1, 10, or 55 ppm fumonisin B1 (FB1) were fed to male and female rats beginning 9 and 2 weeks before mating, respectively, and continuing throughout mating, gestational, and lactational phases of the study. CM caused nephropathy, typical of FB1, in males fed > or = 10 ppm and females fed 55 ppm FB1. No significant reproductive effects were found in males (n = 12/group), dams, and fetuses examined on gestation day 15 (G15) (n > or = 8/group), or dams and litters through day 21 postpartum (n > or = 9/group). Litter weight gain in the 10 or 55 ppm FB1 groups was slightly decreased; however, gross litter weight and physical development of offspring were not affected. Altered SL ratios indicative of fumonisin exposure, specifically increased sphinganine to sphingosine ratios, were found in the livers of dams from the 55-ppm FB1 group on G15. However, SL ratios of abdominal slices, containing liver and kidney, of fetuses from control and high-dose litters did not differ. In a second experiment, two dams were injected intravenously on G15 with 101 micrograms [14C]FB1 (3.179 x 10(5) dpm). After 1 hr, which allowed for ca. 98% of the dose to be cleared from the maternal blood, negligible amounts of radioactivity were found in the fetuses. Together, these results indicate that the CM, and by inference FB1, did not have significant reproductive effects at doses which are minimally toxic, and further suggest that little in utero FB1 exposure occurred through G15.
伏马菌素是由串珠镰刀菌和其他镰刀菌属产生的霉菌毒素。它们常见于玉米及玉米类食品中。伏马菌素可抑制鞘脂（SL）生物合成，改变细胞内鞘脂谱，进而可能影响细胞增殖和分化，而这两个过程对生殖都很重要。然而，关于串珠镰刀菌或伏马菌素对哺乳动物生殖或发育影响的报道较少。为研究这种真菌的生殖影响，从交配前9周和2周开始，分别给雄性和雌性大鼠喂食用有毒串珠镰刀菌菌株MRC 826（CM）的培养物配制的日粮，以提供0、1、10或55 ppm伏马菌素B1（FB1），并在整个交配、妊娠和哺乳期持续喂食。CM使摄入≥10 ppm FB1的雄性大鼠以及摄入55 ppm FB1的雌性大鼠出现了典型的FB1所致肾病。在妊娠第15天（G15）检查的雄性大鼠（每组12只）、母鼠和胎儿（每组≥8只），以及产后21天内的母鼠和幼崽（每组≥9只）中，均未发现明显的生殖影响。10或55 ppm FB1组的幼崽体重增加略有减少；然而，幼崽总体重和后代的身体发育未受影响。在G15时，55 ppm FB1组母鼠的肝脏中发现鞘脂比例改变，表明有伏马菌素暴露，具体表现为鞘氨醇与鞘脂醇的比例增加。然而，对照组和高剂量组幼崽包含肝脏和肾脏的腹部切片的鞘脂比例并无差异。在第二项实验中，于G15给两只母鼠静脉注射101微克[14C]FB1（3.179×10⁵ 每分钟衰变数）。1小时后，此时约98%的剂量已从母鼠血液中清除，在胎儿中发现的放射性物质可忽略不计。总之，这些结果表明，CM以及由此推断的FB1在产生最小毒性的剂量下不会产生明显的生殖影响，进一步表明在G15之前胎儿在子宫内很少接触到FB1。
