Effect of a sulforaphane supplement on muscle soreness and damage induced by eccentric exercise in young adults: A pilot study.

OBJECTIVE: Excessive exercise increases the production of reactive oxygen species in skeletal muscles. Sulforaphane activates nuclear factor erythroid 2-related factor 2 (Nrf2) and induces a protective effect against oxidative stress. In a recent report, sulforaphane intake suppressed exercise-induced oxidative stress and muscle damage in mice. However, the effect of sulforaphane intake on delayed onset muscle soreness after eccentric exercise in humans is unknown. We evaluated the effect of sulforaphane supplement intake in humans regarding the delayed onset muscle soreness (DOMS) after eccentric exercise. RESEARCH METHODS & PROCEDURES: To determine the duration of sulforaphane supplementation, continuous blood sampling was performed and NQO1 mRNA expression levels were analyzed. Sixteen young men were randomly divided into sulforaphane and control groups. The sulforaphane group received sulforaphane supplements. Each group performed six set of five eccentric exercise with the nondominant arm in elbow flexion with 70% maximum voluntary contraction. We assessed muscle soreness in the biceps using the visual analog scale, range of motion (ROM), muscle damage markers, and oxidative stress marker (malondialdehyde; MDA). RESULTS: Sulforaphane supplement intake for 2 weeks increased NQO1 mRNA expression in peripheral blood mononuclear cells (PBMCs). Muscle soreness on palpation and ROM were significantly lower 2 days after exercise in the sulforaphane group compared with the control group. Serum MDA showed significantly lower levels 2 days after exercise in the sulforaphane group compared with the control group. CONCLUSION: Our findings suggest that sulforaphane intake from 2 weeks before to 4 days after the exercise increased NQO1, a target gene of Nrf2, and suppressed DOMS after 2 days of eccentric exercise.

Three-dimensional ultrastructure of feeding tubes and interconnected endoplasmic reticulum in root-knot nematode-induced giant cells in rose balsam.

We investigated the three-dimensional ultrastructure of feeding tubes and the surrounding region in giant cells induced in rose balsam (Impatiens balsamina L.) roots by the root-knot nematode Meloidogyne incognita, using osmium maceration coupled with field emission scanning electron microscopy (FE-SEM). In the roots of 35-day-old galled rose balsam plants, adult nematodes induced the formation of giant cells containing feeding tubes and numerous organelles, including tubular endoplasmic reticulum (ER), cisternal ER, and mitochondria. The feeding tubes were surrounded by fine tubular structures (20-50 nm in diameter), which were in turn surrounded by tubular ER (approximately 120 nm in diameter). The termini of the fine tubular structures appeared to be connected to the surface of the feeding tubes, suggesting that the fine tubular structures were continuous with narrow channels in the feeding tubes. The tubular ER arose from cisternal ER. Large bundles of tubular ER were present near the feeding tube, in the centers of the giant cells, and in the peripheral regions of the giant cells, such as cell wall ingrowths, while smaller bundles of tubular ER formed networks in the giant cells. These observations suggest that tubular ER functions as vascular bundles in giant cells, facilitating the transport of nutrients. We identified capsule-shaped structures (30 µm in diameter) in the giant cells that consisted of smooth, repeatedly branched ER tubules wrapped in several layers of cisternal ER. We propose that lipids and steroids are synthesized at the smooth branched ER and stored in these capsules until needed by the nematode.

The Feeding Behavior of Adult Root-knot Nematodes (Meloidogyne incognita) in Rose Balsam and Tomato.

Meloidogyne incognita is a parasitic root-knot nematode that causes considerable yield loss in a wide range of plants. In this study we documented the movement of adult female nematodes for more than 2 hr in micro-slices of infected tomato (Solanum lycopersicum) and rose balsam (Impatiens balsamina) plants using light and video microscopy. Stylet thrusting was followed by short pumping actions of the esophagus, dorsal esophageal gland ampulla, and metacorpal bulb. Regular thrusting was normally accompanied by head turning and always preceded continuous stylet thrusting aimed at a single point (for 20 to 90 sec). Females often held the stylet in a protruded position, while pulsating the metacorpus bulb, for about 30 sec. Subsequently, the stylet was paused in a retracted position for 5 to 40 sec. This sequence of behavior took 290 to 380 sec to complete. The procedure developed in this study provides a useful cytological technique to investigate the interaction between root-knot nematodes and the giant cells formed by infected plants. Scanning electron microscopy revealed that the head of the adult nematode was located in the narrow intercellular spaces among several giant cells. The anterior part of the head of the adult was folded like a concertina, whereas that of the second-stage juvenile was not. The labial disc and medial lips of second-stage juveniles seemed expanded and sturdy, whereas those of the adult were star-shaped, appeared to be contracted, and softer. These morphological differences in the heads of adult and second-stage juveniles are discussed with respect to their movement.