Effects of substances on plants' active compounds on changes in the hormone levels of the pituitary-thyroid axis in hyperthyroidism and hypothyroidism

The roles of thyroid glands in different functions of the body have been well explained such that hypothyroidism and hyperthyroidism can impair the metabolism and normal functions of the body's tissues. Recently, using medicinal plants and their active compounds in treating diseases has attracted attention, and the people's tendency to use these compounds, which are considered to be low risk and to cause no side effect, is increasing. Because changes in the levels of thyroid hormones have considerable effects on body physiology and play a substantial role in the pathogenesis of different diseases, it is necessary to conduct further studies on hyperthyroidism and hypothyroidism and also the effects of plants and their compounds on thyroid hormone secretion rates. This review was conducted to present the information on thyroid hormones, as metabolism-regulating agents, and their association with different diseases as well as the effects of plant-based active compounds on changes in the hormone levels of the pituitary-thyroid axis in hyperthyroidism and hypothyroidism. Results indicated that disrupted serum levels of the thyroid hormones lead to increased incidence of cardiovascular disease, diabetes, depression, menstrual disorders, and kidney disease. The most important effective compounds on these hormones include flavonoids, coumarins, alkaloids, minerals, essential oil components, such as terpinene, gamma-terpinene, and limonene, and antioxidant compounds that directly influence thyroid and change serum levels of the thyroid hormones through inhibiting thyroid peroxidase. Other mechanisms of change in thyroid hormone levels by plant-based compounds are related to decrease in lipoxygenase activity and increase in the activities of catalase and dismutase. It can therefore be argued that using medicinal plants and their compounds can be a novel and efficient approach to develop drugs for thyroid diseases. © 2018 Pharmacognosy Reviews | Published by Wolters Kluwer - Medknow

Herbal medicine as an auspicious therapeutic approach for the eradication of Helicobacter pylori infection: A concise review.

Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5'-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1β, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori