Binge and Subchronic Exposure to Ketamine Promote Memory Impairments and Damages in the Hippocampus and Peripheral Tissues in Rats: Gallic Acid Protective Effects

Gallic acid enhances memory, learning and reduces neuroinflammation in a rat model of scopolamine-induced cholinergic dysfunction

Gallic acid (GA), a potent polyphenol antioxidant, has demonstrated beneficial effects on the nervous system. This study aimed to investigate the neuroprotective potential of GA on learning and memory in a rat model of scopolamine-induced cholinergic dysfunction. Additionally, the roles of oxidative stress and neuroinflammation were examined. Rats were divided into six groups: Control, scopolamine (2 mg/kg/day), scopolamine plus 25, 50, or 100 mg/kg of GA, and scopolamine plus 2 mg/kg of donepezil (DN, administered once daily). Behavioral performance was evaluated using the Morris Water Maze (MWM) and Passive Avoidance Test. Biochemical parameters were assessed to determine oxidative stress, and gene expression analyses were conducted to explore neuroinflammation in the hippocampus. The behavioral tests revealed that both GA and DN treatments improved the rats' performance in the MWM, as evidenced by their ability to locate the platform and spend more time in the target area. Additionally, GA administration increased the latency of entering the dark compartment and extended the time spent in the light compartment while reducing the frequency of dark compartment entries in the Passive Avoidance Test. Furthermore, GA exhibited antioxidant, anti-acetylcholinesterase, and anti-inflammatory effects, as indicated by the modulation of malondialdehyde levels, thiol content, superoxide dismutase activity, acetylcholinesterase activity, and the expression of inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-6. In conclusion, this study provides evidence for the potential therapeutic benefits of GA in Alzheimer's disease, highlighting its ability to enhance memory function and mitigate oxidative stress, acetylcholinesterase activity, and inflammation.

Therapeutic potential of berries in age-related neurological disorders

Aging significantly impacts several age-related neurological problems, such as stroke, brain tumors, oxidative stress, neurodegenerative diseases (Alzheimer's, Parkinson's, and dementia), neuroinflammation, and neurotoxicity. Current treatments for these conditions often come with side effects like hallucinations, dyskinesia, nausea, diarrhea, and gastrointestinal distress. Given the widespread availability and cultural acceptance of natural remedies, research is exploring the potential effectiveness of plants in common medicines. The ancient medical system used many botanical drugs and medicinal plants to treat a wide range of diseases, including age-related neurological problems. According to current clinical investigations, berries improve motor and cognitive functions and protect against age-related neurodegenerative diseases. Additionally, berries may influence signaling pathways critical to neurotransmission, cell survival, inflammation regulation, and neuroplasticity. The abundance of phytochemicals in berries is believed to contribute to these potentially neuroprotective effects. This review aimed to explore the potential benefits of berries as a source of natural neuroprotective agents for age-related neurological disorders.

Dietary gallic acid as an antioxidant: A review of its food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions

Gallic acid (GA), a dietary phenolic acid with potent antioxidant activity, is widely distributed in edible plants. GA has been applied in the food industry as an antimicrobial agent, food fresh-keeping agent, oil stabilizer, active food wrap material, and food processing stabilizer. GA is a potential dietary supplement due to its health benefits on various functional disorders associated with oxidative stress, including renal, neurological, hepatic, pulmonary, reproductive, and cardiovascular diseases. GA is rapidly absorbed and metabolized after oral administration, resulting in low bioavailability, which is susceptible to various factors, such as intestinal microbiota, transporters, and metabolism of galloyl derivatives. GA exhibits a tendency to distribute primarily to the kidney, liver, heart, and brain. A total of 37 metabolites of GA has been identified, and decarboxylation and dihydroxylation in phase I metabolism and sulfation, glucuronidation, and methylation in phase Ⅱ metabolism are considered the main in vivo biotransformation pathways of GA. Different types of nanocarriers, such as polymeric nanoparticles, dendrimers, and nanodots, have been successfully developed to enhance the health-promoting function of GA by increasing bioavailability. GA may induce drug interactions with conventional drugs, such as hydroxyurea, linagliptin, and diltiazem, due to its inhibitory effects on metabolic enzymes, including cytochrome P450 3A4 and 2D6, and transporters, including P-glycoprotein, breast cancer resistance protein, and organic anion-transporting polypeptide 1B3. In conclusion, in-depth studies of GA on food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions have laid the foundation for its comprehensive application as a food additive and dietary supplement.

Ketamine plus Alcohol: What We Know and What We Can Expect about This

Drug abuse has become a public health concern. The misuse of ketamine, a psychedelic substance, has increased worldwide. In addition, the co-abuse with alcohol is frequently identified among misusers. Considering that ketamine and alcohol share several pharmacological targets, we hypothesize that the consumption of both psychoactive substances may synergically intensify the toxicological consequences, both under the effect of drugs available in body systems and during withdrawal. The aim of this review is to examine the toxicological mechanisms related to ketamine plus ethanol co-abuse, as well the consequences on cardiorespiratory, digestive, urinary, and central nervous systems. Furthermore, we provide a comprehensive discussion about the probable sites of shared molecular mechanisms that may elicit additional hazardous effects. Finally, we highlight the gaps of knowledge in this area, which deserves further research.

Effect of gallic acid on the reproduction of adolescent male Brandt’s voles (Lasiopodomys brandtii)

Gallic acid (GA), a phenol that is present in various plants, potentially contains antioxidant properties. This study aimed to investigate the effects of GA on the reproduction of adolescent male Brandt’s voles (Lasiopodomys brandtii (Radde, 1861)). Antioxidant levels and apoptosis in the testis, as well as reproductive physiology, were evaluated in adolescent males treated with GA. The results showed that a low dose of GA enhanced relative epididymis mass and the sperm density in the epididymis, increased the mRNA levels of steroidogenic acute regulatory protein in the testis, and reduced the percentages of abnormal and dead sperm. In addition, a low dose of GA significantly increased the levels of superoxide dismutase, catalase, and glutathione peroxidase, and decreased the level of malondialdehyde in the testis, as well as the mRNA and protein levels of the apoptosis-related gene, caspase-3. However, a high dose of GA sharply reduced the mean diameter of the seminiferous tubules compared with a low dose. Collectively, these findings demonstrate that GA treatment during puberty affects the reproductive responses of male Brandt’s voles in a dose-dependent manner by regulating antioxidant levels and apoptosis.

Neuroprotective role of gallic acid in aflatoxin B1 -induced behavioral abnormalities in rats

The neurotoxic impact of dietary exposure to aflatoxin B₁ (AFB₁ ) is documented in experimental and epidemiological studies. Gallic acid (GA) is a triphenolic phytochemical with potent anticancer, anti-inflammatory, and antioxidant activities. There is a knowledge gap on the influence of GA on AFB₁ -induced neurotoxicity. This study probed the influence of GA on neurobehavioral and biochemical abnormalities in rats orally treated with AFB₁ per se (75 µg/kg body weight) or administered together with GA (20 and 40 mg/kg) for 28 uninterrupted days. Behavioral endpoints obtained with video-tracking software demonstrated significant (p < .05) abatement of AFB₁ -induced anxiogenic-like behaviors (increased freezing, urination, and fecal bolus discharge), motor and locomotor inadequacies, namely increased negative geotaxis and diminished grip strength, absolute turn angle, total time mobile, body rotation, maximum speed, and total distance traveled by GA. The improvement of exploratory behavior in animals that received both AFB₁ and GA was confirmed by track plots and heat maps appraisal. Abatement of AFB₁ -induced decreases in acetylcholinesterase activity, antioxidant status and glutathione level by GA was accompanied by a marked reduction in oxidative stress markers in the cerebellum and cerebrum of rats. Additionally, GA treatment abrogated AFB₁ -mediated decrease in interleukin-10 and elevation of inflammatory indices, namely tumor necrosis factor-α, myeloperoxidase activity, interleukin-1β, and nitric oxide. Further, GA treatment curtailed caspase-3 activation and histological injuries in the cerebral and cerebellar tissues. In conclusion, abatement of AFB₁ -induced neurobehavioral abnormalities by GA involves anti-inflammatory, antioxidant, and antiapoptotic mechanisms in rats.