An overview of the effect of medicinal herbs on pain.

This paper is typically intended to carefully collect and properly review the antinociceptive activities of medicinal plants. In this review article, by searching keywords of medicinal plants, pain, herbal medicine, antinociceptive, phytotherapy in databases of Web of Science, Scopus, Google Scholar, Springer, Wiley, Proquest, PubMed, Nature, Magiran, Emerald, SID, ISI, and some other indexing cites, or traditional books, desired articles were obtained until 2021. The title of medicinal plants was searched diligently in Persian and English. Ultimately, 270 articles were studied. The findings possibly indicated that several medicinal plants are among the most valuable plants that have antinociceptive activities. There efficiently are various antinociceptive compounds in medicinal plants. The antinociceptive activity of these specific compounds may be through their peculiar effects on the opioid system, cholinergic pathways, and stimulation of GABA receptors, with the peripheral and central antinociceptive mechanism. Antiinflammatory processes, inhibition of the synthesis, and the release of arachidonic acid, prostaglandins, phospholipase, nitric oxide, and cyclooxygenase-2 have been reported as analgesic mechanisms of some herbs. In a reasonable conclusion, our review thoughtfully provides a comprehensive summary of present data from some scientific studies on the common herbs with antinociceptive and antiinflammatory activities.

Activation of androgen receptors alters hippocampal synaptic plasticity and memory retention through modulation of L-type calcium channels.

AIMS: It has been revealed that membrane androgen receptor activation modulates avoidance memory and synaptic plasticity. In a previous study, we showed that Calcineurin, a calcium dependent phosphatase, could be a potential mediator of these AR effects. Also, it is reported that AR activation leads to L-type calcium channel activation. The aim of the current study is to test whether L-type calcium channels are downstream of AR and whether this signal pathway mediates the impairment effect of androgenic steroids on passive avoidance memory and synaptic plasticity. MATERIALS AND METHODS: We measured the effect of Nandrolone Decanoate (AR agonist), AR antagonist (Nilutamide) plus ND or L-type calcium channel inhibitor (Nifedipine) plus ND on passive avoidance performance of adolescent male rats. For extracellular field potential recordings hippocampal slices were perfused with ND, Nilutamide-ND or Nifedipine-ND. KEY FINDINGS: Our results clarified that AR activation by ND could impair avoidance behavior as step through latency decreased in ND-treated group while application of both Nilutamide and Nifedipine reestablished normal avoidance behavior. Also, LTP induction in the CA1 area of hippocampus was diminished by ND perfusion and both AR antagonist and L-type calcium channel inhibitor application lead to normal LTP. These findings support our hypothesis that activation of L-type calcium channels are involved in ARs mechanism effects on both avoidance behavior and hippocampal synaptic plasticity. SIGNIFICANCE: Understanding the biological effects of AR agonists on cognitive processes and its cellular mechanism may be a new/supplementary way to treating fear-related disorders.

The enhancing effects of alcoholic extract of Nigella sativa seed on fertility potential, plasma gonadotropins and testosterone in male rats.

BACKGROUND: The task force on plants for fertility regulation in men continued with its program to identify novel prototypes in plants alleged to have fertility regulating properties. Nigella Sativa seeds are frequently used in folk medicine in the Middle East and some Asian countries for the promotion of good health and treatment of many ailments. OBJECTIVE: To evaluated the role of alcoholic extract of Nigella sativa on fertility potential, Pituitary-testicular axis hormones and Testosterone in male rats. MATERIALS AND METHODS: 24 male rats were randomly divided into 3 groups; control, group A and group B, each group comprising of 8 rats. Animals in control group received 1 ml of normal saline and treatment groups (A and B) received (gavage) graded doses of 200 and 400 mg/kg body weight of alcoholic extract of Nigella sativa seeds on a daily basis for 60 days. At the end of treatment period, fertility parameters such as body and reproductive organs weight, sperm motility, viability and count, epididymal sperm reserve (ESR), daily sperm production (DSP), blood testosterone concentration, Gonadotropins levels and fertility index were measured. RESULTS: There was a significant difference in testes and epididymidis weight, sperm count, ESR, DSP, blood testosterone concentration, LH and fertility index in both the lower dose group and the higher group as compared to the control group. CONCLUSION: The results of this study showed that alcoholic extract of Nigella sativa seed especially in higher doses could increase fertility potential, LH and testosterone concentration in male rats.