Oral administration of coenzyme Q10 prevents cytochrome c release from mitochondria induced by 1-methyl-4-phenylpyridinium ion in mouse brain synaptosomes

Coenzyme Q10 improves the quality of sheep sperm stored at room temperature by mitigating oxidative stress

The purpose of this experiment was to explore whether coenzyme Q₁₀ (CoQ₁₀ ) improves the quality of sheep semen stored at room temperature by attenuating oxidative stress. Semen was diluted without (control group), and with antioxidants (5, 50, 250, and 500 μmol/L CoQ₁₀ ). Sperm kinetic parameters and plasma membrane integrity were determined, and the reactive oxygen species (ROS), malondialdehyde (MDA), adenosine triphosphate (ATP), mitochondrial membrane potential (MMP), total antioxidant capacity (TAOC), catalase (CAT), and superoxide dismutase (SOD) activity were evaluated on the fifth day of semen preservation. The results showed that compared with the control group, the progressive motility in the 50 μmol/L group was higher (p < 0.05) within 2-5 days, and the plasma membrane integrity of sperm was higher in the 50 μmol/L group. The ROS content in the 5 and 50 μmol/L groups was reduced. The MDA level was reduced in the CoQ₁₀ supplementation groups (p < 0.05). Additionally, the CAT, SOD, TAOC, ATP and MMP levels in the 50 μmol/L group were higher than those in the control group (p < 0.05). In conclusion, CoQ₁₀ improved the quality of ram semen by alleviating oxidative stress, and 50 μmol/L CoQ₁₀ was the optimum concentration.

Preventive Effects of Neuroprotective Agents in a Neonatal Rat of Photothrombotic Stroke Model

Neonatal ischemic stroke has a higher incidence than childhood stroke. Seizures are the first sign for the need for clinical assessment in neonates, but many questions remain regarding treatments and follow-up modalities. In the absence of a known pathophysiological mechanism, only supportive care is currently provided. Stroke-induced microglia activation and neuroinflammation are believed to play a central role in the pathological progression of neonatal ischemic stroke. We induced a photothrombotic infarction with Rose Bengal in neonatal rats to investigate the effects of pre- and post-treatment with Aspirin (ASA), Clopidogrel (Clop), and Coenzyme Q10 (CoQ10), which are known for their neuroprotective effects in adult stroke. Pre-stroke medication ameliorates cerebral ischemic injury and reduces infarct volume by reducing microglia activation, cellular reactive oxygen species (ROS) production, and cytokine release. Post-stroke administration of ASA, Clop, and CoQ10 increased motor function and reduced the volume of infarction, and the statistical evidence was stronger than that seen in the pre-stroke treatment. In this study, we demonstrated that ASA, Clop, and CoQ10 treatment before and after the stroke reduced the scope of stroke lesions and increased behavioral activity. It suggests that ASA, Clop, and CoQ10 medication could significantly have neuroprotective effects in the neonates who have suffered strokes.

An alternative medical approach for the neuroprotective therapy to slow the progression of Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the core symptoms such as bradykinesia, resting tremor, rigidity and postural instability. Currently, pharmacotherapy and surgical approaches for the treatments of PD can only improve the neurological symptoms. Therefore, to search neuroprotective therapies using pharmacological and nonpharmacological approaches could be important to delay the progression of pathogenesis in PD. Coenzyme Q10 (CoQ10) is a component of the electron transport chain as well as an important antioxidant in mitochondrial and lipid membranes. The central role of CoQ10 in two areas implicated in the pathogenesis of PD, mitochondrial dysfunction and oxidative damages, suggest that it may be useful for treatment to slow the progression of PD. The neuroprotective effect of CoQ10 has been reported in several in vivo and in vitro models of neurodegenerative disorders. Although CoQ10 attenuated the toxin-induced reduction of dopamine content and tyrosine hydroxylase-immunoreactive neurons in the striatum of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model, it is still unknown how this nutrition affects the mitochondrial function. We demonstrated that oral administration of CoQ10 significantly attenuated the loss of dopaminergic nerve terminals induced by MPTP treatment. Furthermore, our experimental data indicate that an inhibition of mitochondrial cytochrome c release is one of the primary targets for CoQ10 and may lead to a potent neuroprotection.

Oral administration of coenzyme Q₁₀ reduces MPTP-induced loss of dopaminergic nerve terminals in the striatum in mice

The neuroprotective effect of coenzyme Q(10) (CoQ(10)) has been reported in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice. In this study, we investigated whether oral administration of CoQ(10) could protect the striatal dopaminergic (DAergic) nerve terminals against MPTP-induced toxicity in C57BL/6N mice using immunoisolation technique for DAergic synaptosomes. CoQ(10) significantly attenuated decrease in dopamine transporter as well as in synaptophysin and actin protein levels in DAergic synaptosomes from MPTP-treated mice. The effect of CoQ(10) was also observed in crude synaptosomes fraction, but not in homogenate. Our results indicate that the nerve terminals are a site for the action of CoQ(10) against the MPTP-induced DAergic neurodegeneration.

Loss of striatal dopaminergic terminals during the early stage in response to MPTP injection in C57BL/6 mice

The molecular mechanisms underlying MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced dopaminergic (DAergic) neuronal death in vivo are still not fully understood. To investigate the selective DAergic neurotoxicity, we have developed an immunological technique to isolate DAergic synaptosomes from mouse striatal tissues using an antibody against 20 amino acid residues in the extracellular second loop of dopamine transporter (DAT). The DAT protein level in the isolated DAergic synaptosomes was markedly decreased at 16 h after a single injection of 30 mg/kg MPTP, but not in striatal homogenate and crude synaptosomes fraction. GBR-12909, a dopamine uptake inhibitor, completely reversed the MPTP-induced decrease of DAT protein in the DAergic synaptosomes. These results suggest that the isolated DAergic synaptosomes can be useful to identify mechanisms of loss of the nerve terminals.

The anti-apoptotic action of 5-hydroxyindole: protection of mitochondrial integrity

5-Hydroxyindole (5HI), a metabolite of tryptophan, is involved in learning and memory, central neuron system regulation, and anti-oxidant activity. However, its protective action in mitochondrial function is not clear. Here, we tested whether 5HI protects against tert-butylhydroperoxide (t-BHP)-induced oxidative damage and mitochondrial dysfunction in human fibroblast cells. 5HI significantly suppressed t-BHP-induced cytotoxicity as determined by intracellular reactive species generation, lipid peroxidation, glutathione depletion, and peroxynitrite (ONOO(-)) generation. In addition, 5HI reduced t-BHP-induced DNA condensation. Pretreatment with 5HI significantly restored mitochondrial membrane potential (Deltapsim), suggesting that it protected cells against t-BHP-induced apoptosis. Western blot analysis also revealed that 5HI markedly inhibited cytochrome c release and caspase-3 activation, but not caspase-9 activation. Our data suggest that 5HI protects cells by attenuating oxidative stress and consequently protects against mitochondrial dysfunction.