Plants from Genus Dracocephalum in Iran: Pharmacology and Phytochemistry Overview.

BACKGROUND: Genus Dracocephalum belongs to the Lamiaceae family, representing 11 species in Iran, containing D. ghahremanii Jamzad, D. lindbergii Rech. F, D. oligadenium Bornm. & Gauba, D. kotschyi Boiss., D.multicaule, D.Aucheri, D.Subcapitatum, D.Thymifolium, D.Moldavica, D. polychaetum Borm, and D. surmandinum Rech.f. The current study aimed to investigate the morphological and phytochemical properties of Dracocephalum species in Iran and their pharmacological effects. METHODS: The search was restricted to scientific articles from PubMed, Google Scholar, Science Direct, SpringerLink, and Scopus. The search was limited to scientific journals, books, and book chapters focusing on the medicinal properties of Dracocephalum in Iran for the era from 1993 to 2020. RESULTS: Findings show that Dracocephalum species were utilized to treat various disorders in traditional medicine. Phytochemical studies show that the main constituents isolated from the plant consist of lignans, phytosterol, flavonoids, phenols, alkaloids, Sesquiterpenes, and oxygenated and hydro carbonated monoterpenes. These main components are responsible for antihyperlipidemic, antimicrobial, anticancer, antispasmodic, antioxidant, and cardiovascular effects of the plant. CONCLUSION: This plant has a good potential for drug discovery and curing different diseases. Therefore, more research will be done on the Iranian species of Dracocephalum based on clinical and animal studies to develop an effective drug formulation.

Ellagic acid ameliorates neuroinflammation and demyelination in experimental autoimmune encephalomyelitis: Involvement of NLRP3 and pyroptosis.

Multiple sclerosis (MS) is presented as the most common autoimmune and demyelinating neurological disorder with incapacitating complications and with no definite therapy. Most treatments for MS mainly focus on attenuation of its severity and recurrence. To model MS reliably to study pathogenesis and efficacy of possible chemicals, experimental autoimmune encephalomyelitis (EAE) condition is induced in rodents. Ellagic acid is a neuroprotective polyphenol that can protect against demyelination. This study was planned and conducted to assess its possible beneficial effect in MOG-induced EAE model of MS with emphasis on uncovering its modes of action. Ellagic acid was given p.o. (at doses of 10 or 50 mg/kg/day) after development of clinical signs of MS to C57BL/6 mice immunized with MOG35-55. Results showed that ellagic acid can ameliorate severity of the disease and partially restore tissue level of TNFα, IL-6, IL-17A and IL-10. Besides, ellagic acid lowered tissue levels of NLRP3 and caspase 1 in addition to its mitigation of neuroinflammation, demyelination and axonal damage in spinal cord specimens of EAE group. As well, ellagic acid treatment prevented reduction of MBP and decreased GFAP and Iba1 immunoreactivity. Taken together, ellagic acid can decrease severity of EAE via amelioration of astrogliosis, astrocyte activation, demyelination, neuroinflammation and axonal damage that is partly related to its effects on NLRP3 inflammasome and pyroptotic pathway.

Trigonelline mitigates lipopolysaccharide-induced learning and memory impairment in the rat due to its anti-oxidative and anti-inflammatory effect.

Brain inflammation is associated with cognitive dysfunction, especially in elderly. Trigonelline is a plant alkaloid and a major component of coffee and fenugreek with anti-diabetic, antioxidant, anti-inflammatory, and neuroprotective effects. In this study, the beneficial effect of trigonelline against lipopolysaccharide (LPS)-induced cognitive decline was assessed in the rat. LPS was injected i.p. at a dose of 500 µg/kg to induce neuroinflammation and trigonelline was administered p.o. at doses of 20, 40, or 80 mg/kg/day 1 h after LPS that continued for one week. Trigonelline-treated LPS-challenged rats showed improved spatial recognition memory in Y maze, discrimination ratio in novel object discrimination test, and retention and recall in passive avoidance paradigm. Additionally, trigonelline lowered hippocampal malondialdehyde (MDA) and acetylcholinesterase (AChE) activity and improved superoxide dismutase (SOD), catalase, and glutathione (GSH). Furthermore, trigonelline depressed hippocampal nuclear factor-kappaB (NF-κB), toll-like receptor 4 (TLR4), and tumor necrosis factor α (TNF α) in LPS-challenged rats. All of the effects of trigonelline followed a dose-dependent pattern and in some aspects, it acted even better than the routinely-used anti-inflammatory drug dexamethasone. Collectively, trigonelline is capable to diminish LPS-induced cognitive decline via suppression of hippocampal oxidative stress and inflammation and appropriate modulation of NF-κB/TLR4 and AChE activity.