Protection of cholinergic and antioxidant system contributes to the effect of berberine ameliorating memory dysfunction in rat model of streptozotocin-induced diabetes.

Memory impairment induced by streptozotocin in rats is a consequence of changes in CNS that are secondary to chronic hyperglycemia, impaired oxidative stress, cholinergic dysfunction, and changes in glucagon-like peptide (GLP). Treatment with antihyperglycemics, antioxidants, and cholinergic agonists are reported to produce beneficial effect in this model. Berberine, an isoquinoline alkaloid is reported to exhibit anti-diabetic and antioxidant effect, acetylcholinesterase (AChE) inhibitor, and increases GLP release.

Berberine protects C57BL/6J mice against ethanol withdrawal-induced hyperexcitability.

Berberine ([C20H18NO4](+) ), one of the major constituents of the Chinese herb Rhizoma coptidis, is an isoquinoline alkaloid. Plethora of recent reports has indicated its ability to modulate several neurotransmitter systems, especially those implicated in ethanol dependence. Thus, the influence of berberine treatment on the development and expression of ethanol dependence was tested by using the ethanol withdrawal-induced hyperexcitability paradigm.

Inhibitory effect of berberine on the motivational effects of ethanol in mice.

It is believed that drug-induced rewarding effects play an important role in the development of substance dependence. Recently, berberine was reported to inhibit the rewarding effects of drugs of abuse such as cocaine, morphine, and nicotine. Berberine is also demonstrated to modulate the activity of several neurotransmitter systems like, dopamine, nitric oxide, serotonin, and NMDA, which are implicated in rewarding effects of ethanol.

Anticonvulsant activity of berberine, an isoquinoline alkaloid in mice.

Berberine, an isoquinoline alkaloid is reported to modulate several neurotransmitter systems like N-methyl-D-aspartate, nitric oxide and serotonin, which modulate convulsions. In addition, it is suggested that Berberis vulgaris may be useful in treatment of convulsion and epilepsy. Therefore, the present study investigated the effects of berberine in pentylenetetrazole, maximal electroshock (MES) and kainic acid (KA)-induced convulsions.

Ameliorative effect of quercetin on memory dysfunction in streptozotocin-induced diabetic rats.

Diabetes-related cognitive dysfunction is a consequence of changes within the central nervous system that are secondary to chronic hyperglycemia, oxidative stress, and cholinergic dysfunction, and probably therefore anti-diabetics, anti-oxidants, and acetylcholine esterase (AChE) inhibitors were found to have beneficial effects in animal models. Quercetin, a bioflavonoid widely distributed in the plants is reported to be a potent anti-diabetic, anti-oxidant, AChE inhibitor, and memory enhancer. Therefore, we screened its influence against diabetes-induced cognitive dysfunction in streptozotocin-induced diabetic rats using Morris water and elevated plus maze (EPM) paradigms.

Inhibitory influence of mecamylamine on the development and the expression of ethanol-induced locomotor sensitization in mice.

Several evidences have indicated the involvement of neuronal nicotinic acetylcholine receptors (nAChR) in behavioral effects of drugs of abuse, including ethanol. nAChRs are implicated in ethanol-induced behaviors as well as neurochemical responses to ethanol. Recently, it is demonstrated that mecamylamine, a nAChR antagonist blocks cocaine-, d-amphetamine-, ephedrine-, nicotine-, and methylphenidate-induced psychomotor sensitization.

Reversal by quercetin of corticotrophin releasing factor induced anxiety- and depression-like effect in mice.

Quercetin is a bioflavonoid reported to produce variety of behavioral effects like anxiolytic, antidepressant, etc. Recent gathering evidences indicated that quercetin attenuates stress-induced behavioral and biochemical effects. It also decreases CRF expression in the brain.

Inhibitory influence of mecamylamine on ethanol withdrawal-induced symptoms in C57BL/6J mice.

Several reports show the involvement of neuronal nicotinic acetylcholine receptors (nAChRs) in the behavioral effects of ethanol, including ethanol drinking and relapse. Therefore, this study evaluated the effects of mecamylamine, a nAChR antagonist, on ethanol withdrawal signs. Ethanol dependence was induced in C57BL/6J mice by ethanol liquid diet administration.

Quercetin pretreatment increases the bioavailability of pioglitazone in rats: involvement of CYP3A inhibition.

Herbal antidiabetic preparations are often used as an add-on therapy in diabetes and such herbal preparations often contains quercetin that can inhibit cytochrome P450 (CYP) 3A4. This enzyme is responsible for metabolizing pioglitazone, a commonly used antidiabetic agent. Hence, it was speculated that quercetin may influence the bioavailability of pioglitazone, which could be particularly crucial, as any increment in its plasma levels may raise safety concerns.