Tibolone Prevents Oxidation and Ameliorates Cholinergic Deficit Induced by Ozone Exposure in the Male Rat Hippocampus

Abstract

Oxidative stress is related to the development of central nervous system diseases involving memory processes. Cholinergic system and memory processes are disrupted by ozone exposure. In rats, ozone induces motor disturbances and memory deficits as well as biochemical changes in brain regions related to memory processes. In this work, we analyzed the effect of chronic tibolone (TIB) administration in central nervous system, specifically the content of choline acetyltransferase, acetylcholinesterase, acetylcholine and oxidative stress markers in the hippocampus of male rats exposed to ozone. Our results reveal a neuroprotective effect of TIB treatment on neuronal damage induced by chronic ozone exposure. Furthermore, we suggest that TIB can prevent memory deficits by providing a protective effect against oxidative stress and the cholinergic system disruption induced by ozone exposure. Together, these findings present a potential neuroprotective effect of TIB in processes linked to memory deficits induced by aging or neurodegenerative diseases.

Identification of two arylimides as cholinesterase inhibitors and testing of propranolol addition on impaired rat memory

“…On the other hand, there was no additive effect for each arylimide in combination with propranolol. This result could be related to the shared region for the binding of these compounds on AChE, which is in agreement with the idea that the inhibition of this enzyme is the main mechanism of action for modulating the memory performance in the presently employed animal model (Farfán‐García et al, ; Mitsushima et al, ). However, other mechanisms have been mentioned for the modulation of the activity or expression of adrenoceptors in the brain (Ciprés‐Flores et al, ; Dobarro et al, ; Liu, Ma, et al, ; Lonergan et al, ).…”

“…Eighty male rats were randomly divided into eight experimental groups ( n = 10). In Group 1, the control animals were sham‐operated (Farfán‐García et al, ; Wang & Xiang, ) and treated with the vehicle for 15 days. The animals in Groups 2–8 were orchiectomized and treated by oral administration for 15 days with vehicle (Group 2), neostigmine (14 μg/kg, Group 3), propranolol (571 μg/kg, Group 4), compound C7 (70 μg/kg, Group 5), compound C8 (70 μg/kg, Group 6), compound C7 and propranolol (Group 7), or compound C8 and propranolol (Group 8).…”

“…AcONa, sodium acetate; RT, room temperature; THF, tetrahydrofuran For evaluating memory, passive avoidance training (PAT) was performed for every group. The PAT test was applied as reported previously (Ciprés-Flores et al, 2019;Farfán-García et al, 2014). In brief, we used a model with two sections, the safety and the shock compartments.…”

Acute Administration of Tibolone Prevents Oxidative Stress in Ovariectomized Rats Fed High-Fat-and-Fructose Diet

“…Tibolone (1 mg/kg; Livial®, Organon, Mexico) or vehicle (water) was administered daily by oral gavage for seven days. It has been recently demonstrated that this dose of TB has neuroprotective properties by reducing lipid peroxidation and ameliorating behavioral/functional deficits after ozone exposure [12,17]. The solutions containing TB or vehicle were independently coded before administration (▶ Fig.…”

“…Tibolone (TB), a synthetic steroid that has been used as an elective treatment for the relief of menopausal symptoms, and its various metabolites have estrogenic as well as progestogen/androgenic effects [11]. TB treatment in rats decreased OS markers [12], body weight, and total cholesterol levels [13], whereas in studies conducted with postmenopausal women, TB improved blood pressure, glycemia [14], insulin levels, HDL cholesterol, and triglycerides [15]. However, the acute effects of HT with TB on metabolic parameters and OS markers associated with the first stages of ED are still unknown.…”