ABSTRACT
Chirality, a fundamental principle in chemistry, biology, and medicine, is prevalent in nature and in organisms. Chiral molecules, such as DNA, RNA, and proteins, are crucial in biomolecular synthesis, as well as in the development of functional materials. Among these, 1,1'-binaphthyl-2,2'-diol (BINOL) stands out for its stable chiral configuration, versatile functionality, and commercial availability. BINOL is widely employed in asymmetric catalysis and chiral materials. This review mainly focuses on recent research over the past five years concerning the use of BINOL derivatives for constructing chiral macrocycles and cages. Their contributions to chiral luminescence, enantiomeric separation, transmembrane transport, and asymmetric catalysis were examined.
ABSTRACT
OBJECTIVE: To investigate the inhibitory effect of tetramethylpyrazine (Tet) preconditioning on overload training-induced myocardial apoptosis in rats, and to explore cardioprotective mechanisms of Tet preconditioning. METHODS: A total of 25 male Sprague-Dawley rats were randomly divided into three groups, including the control group (n=5), the overload training group (overload training for 8 weeks, n=10), and the Tet preconditioning group (Tet preconditioning for 8 weeks before overload training, n=10). After 8 weeks, cardiac structure and myocardial apoptosis were analyzed by histology, transmission electron microscopy, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay staining. The expressions of Bcl-2, Bax, Caspase-3, and Caspase-9 in myocardium were evaluated by immunohistochemical staining. RESULTS: Overload training caused swelling, disorder, partial rupture, and necrosis of myocardial focal necrotic fibers, as well as mitochondrial vacuolization, cristae rupturing, and blurring. In contrast, Tet preconditioning attenuated the swelling of myocardial fibers, decreased the amount of ruptured fibers, and inhibited mitochondrial vacuolization, resulting in clear cristae. Overload training significantly increased Bax expression and decreased Bcl-2/Bax ratio when compared with the control group (P<0.01). Conversely, Tet preconditioning significantly increased Bcl-2 expression and the Bcl-2/Bax ratio as compared with the overload training group (P<0.05). Overload training dramatically increased the expressions of Caspase-3 and Caspase-9 when compared with the control groupP<0.05). Following Tet preconditioning, the expression of Caspase-3 was significantly reduced compared with the overload training group (P<0.05), while Caspase-9 expression showed a slight decline (P>0.05). CONCLUSION: Tet preconditioning increased the expression of Bcl-2 and reduced the expression of Caspase-3, thereby attenuating overload training-induced myocardial apoptosis, protecting against overload training-induced myocardial injury, and reducing damage to the myocardium due to overload training.
