Integration of qRT-PCR and Immunohistochemical Techniques for mRNA Expression and Localization of m1AChR in the Brain of Aging Rat

Regulatory mechanism of perinatal nonylphenol exposure on cardiac mitochondrial autophagy and the PINK1/Parkin signaling pathway in male offspring rats

OBJECTIVE

This study investigated whether perinatal exposure to nonylphenol (NP) induces mitochondrial autophagy (i.e., mitophagy) damage in neonatal rat cardiomyocytes (NRCMs) and whether the PINK1/Parkin signaling pathway is involved in NP-induced primary cardiomyocyte injury.

METHODS AND RESULTS

In vivo: Perinatal NP exposure increased apoptosis and mitochondrial damage in NRCMs. Mitochondrial swelling and autophagosome-like structures with multiple concentric membranes were observed in the 100 mg/kg NP group, with an increase in the number of autophagosomes. Disorganized fiber arrangement and elevated serum myocardial enzyme levels were observed with increasing NP dosage. Additionally, NP exposure led to increased MDA levels and decreased SOD activity and ATP levels in myocardial tissue. The mRNA expression levels of autophagy-related genes, including Beclin-1, p62, and LC3B, as well as the expression of mitochondrial autophagy-related proteins (PINK1, p-Parkin, Parkin, Beclin-1, p62, LC3-I, LC3-II, and LC3-II/I) and apoptosis-related proteins (Bax and caspase-3), increased, whereas the expression levels of the mitochondrial membrane protein TOMM20 and the anti-apoptotic protein Bcl-2 decreased. In vitro: NP increased ROS levels, LDH release, and decreased ATP levels in NRCMs. CsA treatment significantly inhibited the expression of autophagy-related proteins (Beclin-1, LC3-II/I, and p62) and apoptosis-related proteins (caspase-3 and Bax), increased the expression levels of TOMM20 and Bcl-2 proteins, increased cellular ATP levels, and inhibited LDH release. The inhibition of the PINK1/Parkin signaling pathway suppressed the expression of mitochondrial autophagy-related proteins (PINK1, p-Parkin, Parkin, Beclin-1, LC3-II/I, and p62) and apoptosis-related proteins (caspase-3 and Bax), increased TOMM20 and Bcl-2 protein expression, increased ATP levels, and decreased LDH levels in NRCMs.

CONCLUSIONS

This study is novel in reporting that perinatal NP exposure induced myocardial injury in male neonatal rats, thereby inducing mitophagy. The PINK1/Parkin signaling pathway was involved in this injury by regulating mitophagy.

The benefits of grape seed extract in neurological disorders and brain aging

Common neurological disorders, including neurodegenerative diseases, stroke, epilepsy, autism and psychiatric disorders, affect many people worldwide and threaten their lives and health by inducing movement disorders, behavioral disorders, or a combination of both. Oxidative stress and neuroinflammation play a central role in neuronal damage and neurological diseases induction and progression. In addition, protein homeostasis (proteostasis) impairment occurs in many neurodegenerative diseases, which plays a critical role in the progression of the pathology. Grape seed contains several flavonoids and non-flavonoids and exerts potent antioxidant and anti-inflammatory effects. In addition, polyphenols and flavanols can maintain cellular proteostasis. Since impaired proteostasis is closely involved in all amyloid diseases, particularly neurodegenerative diseases, grape seeds extract can be a valuable therapeutic agent. Therefore, this review discusses the protective and therapeutic mechanisms of grape seed against neurological disorders and, in the end, links GSE to microRNAs as future therapeutic developments.

Novel shaking exercises for hippocampal and medial prefrontal cortex functioning maintain spatial working memory

INTRODUCTION

The decline in spatial working memory is one of the earliest signs of normal brain aging.

OBJECTIVE

We developed a novel physical exercise method, termed the "shaking exercise," to slow down this process.

METHODS

The experimental protocol included administering the shaking exercise for 8-32 weeks in male senescence-accelerated mouse prone 10 (SAMP-10). They were subjected to the T-maze test, followed by immunohistochemical analysis, to assess the influence of the shaking exercise on the M1 muscarinic acetylcholine receptor (CHRM1) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) of the dorsal hippocampus and medial prefrontal cortex (dHC-mPFC).

RESULTS

The T-maze test demonstrated that the shaking group had less hesitation in the face of selecting direction at week 24. In the immunohistochemical analysis, more CHRM1s were in the CA3 subregion and more AMPARs were in the subiculum. CHRM1s and AMPARs were maintained in the CA1 region and the mPFC. The CHRM1s seem to have a positive effect on the AMPAR in the dentate gyrus (DG) region and the CA3 region. In the CA1 region, CHRM1s were negatively correlated with AMPARs. In addition, high-density neurons were expressed in the shaking group in the upstream DG, the middle part and the distal part of CA3, the distal part of CA1, and the mPFC.

CONCLUSIONS

Our results raise the possibility that maintenance of the spatial working memory effect observed with the shaking exercise is driven in part by the uneven affection of CHRM1s and AMPARs in the dHC-mPFC circuit system and significantly maintains the neuronal expression in the dHC-mPFC.