A Pacific Oyster-Derived Antioxidant, DHMBA, Protects Renal Tubular HK-2 Cells against Oxidative Stress via Reduction of Mitochondrial ROS Production and Fragmentation.

The kidney contains numerous mitochondria in proximal tubular cells that provide energy for tubular secretion and reabsorption. Mitochondrial injury and consequent excessive reactive oxygen species (ROS) production can cause tubular damage and play a major role in the pathogenesis of kidney diseases, including diabetic nephropathy. Accordingly, bioactive compounds that protect the renal tubular mitochondria from ROS are desirable. Here, we aimed to report 3,5-dihydroxy-4-methoxybenzyl alcohol (DHMBA), isolated from the Pacific oyster (Crassostrea gigas) as a potentially useful compound. In human renal tubular HK-2 cells, DHMBA significantly mitigated the cytotoxicity induced by the ROS inducer L-buthionine-(S, R)-sulfoximine (BSO). DHMBA reduced the mitochondrial ROS production and subsequently regulated mitochondrial homeostasis, including mitochondrial biogenesis, fusion/fission balance, and mitophagy; DHMBA also enhanced mitochondrial respiration in BSO-treated cells. These findings highlight the potential of DHMBA to protect renal tubular mitochondrial function against oxidative stress.

Manipulation of Epileptiform Electrocorticograms (ECoGs) and Sleep in Rats and Mice by Acupuncture.

Ancient Chinese literature has documented that acupuncture possesses efficient therapeutic effects on epilepsy and insomnia. There is, however, little research to reveal the possible mechanisms behind these effects. To investigate the effect of acupuncture on epilepsy and sleep, several issues need to be addressed. The first is to identify the acupoints, which correspond between humans, rats, and mice. Furthermore, the depth of insertion of the acupuncture needle, the degree of needle twist in manual needle acupuncture, and the stimulation parameters for electroacupuncture (EA) need to be determined. To evaluate the effects of acupuncture on epilepsy and sleep, a feasible model of epilepsy in rodents is required. We administer pilocarpine into the left central nucleus of the amygdala (CeA) to simulate focal temporal lobe epilepsy (TLE) in rats. Intraperitoneal (IP) injection of pilocarpine induces generalized epilepsy and status epilepticus (SE) in rats. Five IP injections of pentylenetetrazol (PTZ) with a one-day interval between each injection successfully induces spontaneous generalized epilepsy in mice. Recordings of electrocorticograms (ECoGs), electromyograms (EMGs), brain temperature, and locomotor activity are used for sleep analysis in rats, while ECoGs, EMGs, and locomotor activity are employed for sleep analysis in mice. ECoG electrodes are implanted into the frontal, parietal, and contralateral occipital cortices, and a thermistor is implanted above the cerebral cortex by stereotactic surgery. EMG electrodes are implanted into the neck muscles, and an infrared detector determines locomotor activity. The criteria for categorizing vigilance stages, including wakefulness, rapid eye movement (REM) sleep, and non-REM (NREM) sleep are based on information from ECoGs, EMGs, brain temperature, and locomotor activity. Detailed classification criteria are stated in the text.