Exploring nature's hidden treasure: Unraveling the untapped phytochemical and pharmacological potentials of Clinopodium vulgare L. - A hidden gem in the Lamiaceae family

Folk medicine, rooted in historical practice, has long been used for medicinal purposes, emphasizing the need to ensure the safety, quality, and efficacy of herbal medicines. This imperative has grown over time, prompting collaborative efforts to document historical records and preserve invaluable knowledge of medicinal plants. The Lamiaceae (Labiatae) family, renowned for its rich assortment of medicinal plants characterized by high concentrations of volatile oils, stands out in this regard. This review focuses on Clinopodium vulgare (C. vulgare) L., commonly known as wild basil or basil thyme, a significant species within the Lamiaceae family found across diverse global regions. C. vulgare boasts a storied history of application in treating various ailments, such as gastric ulcers, diabetes, and inflammation, dating back to ancient times. Rigorous research has substantiated its pharmacological properties, revealing its antioxidant, antiviral, antibacterial, anti-inflammatory, anticancer, antihypertensive, and enzyme-inhibitory effects. This comprehensive review provides an insightful overview of the Lamiaceae family, elucidates the extraction methods employed to obtain medicinal compounds, explores the phytoconstituents present in C. vulgare, and systematically details its diverse pharmacological properties. Additionally, the review delves into considerations of toxicity. By synthesizing this wealth of information, this study opens avenues for the potential therapeutic applications of C. vulgare. The practical value of this research lies in its contribution to the understanding of medicinal plants, mainly focusing on the pharmacological potential of C. vulgare. This exploration enriches our knowledge of traditional medicine and paves the way for innovative therapeutic approaches, offering promising prospects for future drug development. As the demand for natural remedies continues to increase, this work provides a valuable resource for researchers, practitioners, and stakeholders in herbal medicine and pharmacology.

A behavioral and molecular study; ameliorated anxiety-like behavior and cognitive dysfunction in a rat model of chronic unpredictable stress treated with oregano extract

OBJECTIVE

Chronic stress is considered a severe risk factor leading to various disorders, including anxiety and cognitive decline. The present study aimed to investigate the effects of Origanum vulgare (oregano) extract on improving anxiety-like behavior and learning and memory defection caused by chronic unpredictable stress (CUS).

METHOD

A 10-day CUS protocol was executed on male rats, and on day 10, their anxiety, learning, and memory status were evaluated. After that, in addition to the CUS, the rats were treated with the oregano extract for 2 weeks. Then, the expression of BDNF, TrkB, and TLR2/4 genes in the hippocampus and prefrontal cortex of the rats was evaluated. Also, the liver- and kidney-related serum parameters, including triglycerides, total cholesterol, HDL, LDL, creatinine, urea, serum glucose, alanine aminotransferase, and aspartate aminotransferase were assessed. Further, the extract's lethal effect and its impact on animals' body weight were investigated.

RESULTS

Behavioral tests confirmed the anxiety-like behavior and learning-memory function impairment caused by CUS. In contrast, the administration of the extract could significantly alleviate the mental deficiencies and diminished anxiety-like behaviors. Molecular assessments showed that CUS could markedly decrease the BDNF and TrkB genes' expression levels while increasing that of TLR2 and TLR4. In contrast, in extract-treated animals, mRNA levels of BDNF and TrkB considerably increased, yet TLR2 and TLR4 mRNA levels reduced. Additionally, consumption of the extract caused weight gain, while having no lethality and detrimental effect on the liver and kidneys functions.

CONCLUSIONS

These findings indicate the anxiolytic properties of the extract and its improving effect on cognitive dysfunction.

Swimming training and Plantago psyllium ameliorate cognitive impairment and glucose tolerance in streptozotocin-nicotinamide-induced type 2 diabetic rats

Brain malfunction is common in diabetic patients. On the other hand, a growing body of research points to the beneficial effect of medicinal plants and exercise training on insulin sensitivity and brain function. Therefore, the aim of the present study was to investigate the effect of co-administration of swimming training and Plantago psyllium (mixed with standard pelleted food at a weight ratio of 5%) on learning and memory impairment and glucose tolerance in type 2 diabetic rats. For this purpose, 10 healthy and 40 rats with type 2 diabetes were randomly allocated to five groups: healthy sedentary control group (Con), sedentary diabetic group (D), diabetic group subjected to swimming training (D + Tr), diabetic group receiving P. psyllium (D + Ps), and diabetic group subjected to swimming training and receiving P. psyllium (D + Ps + Tr). Diabetes was induced by a single intraperitoneal injection of nicotinamide (120 mg/kg) and streptozotocin (65 mg/kg) separately with 15 min intervals. Experimental groups were treated with swimming training and P. psyllium independently and simultaneously for 12 weeks. Lipid profile and food intake were measured and also, glucose tolerance was evaluated by glucose area under the curve (AUCg) using an oral glucose tolerance test. Passive avoidance learning (PAL) and memory were evaluated by shuttle box test and cognitive memory was assessed by novel object recognition (NOR) and elevated plus-maze (EPM) tests. Diabetic rats exhibited a significant increase in food intake, lipid profile, and AUCg compared to healthy rats. Step-through latency in the PAL acquisition trial (STL-a) and retention test (STL-r) were significantly lower in diabetic rats than in the control group. In the diabetic group without treatment, time spent in the dark compartment increased compared to the control group in the shuttle box test. Discrimination index and distance traveled reduced in diabetic rats. On the other hand, swimming training and P. psyllium alleviated food intake, lipid profile, and glucose tolerance in diabetic rats. Also, the STL-a, STL-r, discrimination index, and distance travelled in the D + Ps + Tr group were significantly more than the diabetic group. Results showed that 12 weeks of swimming training and receiving P. psyllium improved memory deficit in streptozotocin-nicotinamide-induced type 2 diabetic rats possibly through hypolipidemic and hypoglycemic effects. These results suggest that the administration of swimming training and P. psyllium simultaneously might be an effective intervention for the treatment of diabetes-induced behavioral deficits.

Origanum vulgare ssp. hirtum (Lamiaceae) Essential Oil Prevents Behavioral and Oxidative Stress Changes in the Scopolamine Zebrafish Model

Origanum vulgare ssp. hirtum has been used as medicinal herbs promoting antioxidant, anti-inflammatory, antimicrobial, and neuroprotective activities. We investigated the protective effects and the mechanism of O. vulgare ssp. hirtum essential oil (OEO) on cognitive impairment and brain oxidative stress in a scopolamine (Sco)-induced zebrafish (Danio rerio) model of cognitive impairment. Our results show that exposure to Sco (100 µM) leads to anxiety, spatial memory, and response to novelty dysfunctions, whereas the administration of OEO (25, 150, and 300 µL/L, once daily for 13 days) reduced anxiety-like behavior and improved cognitive ability, which was confirmed by behavioral tests, such as the novel tank-diving test (NTT), Y-maze test, and novel object recognition test (NOR) in zebrafish. Additionally, Sco-induced brain oxidative stress and increasing of acetylcholinesterase (AChE) activity were attenuated by the administration of OEO. The gas chromatography-mass spectrometry (GC-MS) analyses were used to elucidate the OEO composition, comprising thymol (38.82%), p-cymene (20.28%), and γ-terpinene (19.58%) as the main identified components. These findings suggest the ability of OEO to revert the Sco-induced cognitive deficits by restoring the cholinergic system activity and brain antioxidant status. Thus, OEO could be used as perspective sources of bioactive compounds, displaying valuable biological activities, with potential pharmaceutical applications.