Corrigendum to "Naturally occurring sesquiterpene lactones and their semi-synthetic derivatives modulate PGE2 levels by decreasing COX2 activity and expression" [Heliyon 5 (3) (March 2019) e01366].

[This corrects the article DOI: 10.1016/j.heliyon.2019.e01366.].

Naturally occurring sesquiterpene lactones and their semi-synthetic derivatives modulate PGE2 levels by decreasing COX2 activity and expression.

Plants of the Asteraceae family have been used in traditional medicine for centuries due to their main antimicrobial and analgesic activities. A liniment from Artemisia californica has recently been tested on patients affected by either acute pain or chronic pain conditions with great success. The aim of this study was to evaluate the anti-inflammatory activity of sesquiterpene lactones (SLs), representing the majority in the Asteraceae family. Leucodin, α-santonin and sclareolide (three SLs) were chosen to undergo chemical modifications. This pool of molecules underwent molecular modeling experiments using an in-house program, WATGEN, predicting the water network and its contribution to the overall affinity of the enzyme-ligand complex. The anti-inflammatory activity and the ability of compounds to modulate COX-2 expression have been evaluated in LPS-stimulated RAW 264.7 cells and in RIF-1 cells treated according to the Photodynamic Therapy (PDT) protocols using Photoprin (PH) as photosensitizer. Furthermore, commercially available assay kits were used to evaluate the concentration of PGE-2 and the direct inhibition of COX-2. All the tested molecules fit well in the enzyme binding pocket, but to get a substantial inhibition of the expression and activity of the enzyme as well as a reduction in the PGE2 concentration, high concentrations of the compounds are needed. The only exceptions being leucodin itself and FP6, one of the α-santonin derivatives, presenting a CF3 functional group. We believe that this class of compounds has some interesting potential in the treatment of pain and inflammation. Although, the activity seems to be due to a mechanism related to the expression of the COX enzymes rather than on a direct inhibition.

Salvia mellifera-How Does It Alleviate Chronic Pain?

Black sage, Salvia mellifera, can be made into a sun tea that is used as a foot soak to treat pain patients. The monoterpenoids and diterpenoids in the preparation penetrate the skin of the feet and stop the pain chemokine cycle, which may be the basis of chronic pain. Several chronic pain patients have reported long-term improvements in their pain after treatment with the preparation.

The Effects of Yin, Yang and Qi in the Skin on Pain.

The most effective and safe treatment site for pain is in the skin. This chapter discusses the reasons to treat pain in the skin. Pain is sensed in the skin through transient receptor potential cation channels and other receptors. These receptors have endogenous agonists (yang) and antagonists (yin) that help the body control pain. Acupuncture works through modulation of these receptor activities (qi) in the skin; as do moxibustion and liniments. The treatment of pain in the skin has the potential to save many lives and improve pain therapy in most patients.

Preclinical and clinical examinations of Salvia miltiorrhiza and its tanshinones in ischemic conditions.

Salvia miltiorrhiza (Labiatae, Laminaceae), danshen, is an annual sage mainly found in China and neighboring countries. The crude drug (dried root) and its preparations are currently used in China to treat patients suffering from heart attack, angina pectoris, stroke and some other conditions. The use of S. miltiorrhiza has been increasing in the management of stroke. Pharmacological examinations showed that the plant and its active ingredients, tanshinones and salvianolic acids, have anticoagulant, vasodilatory, increased blood flow, anti-inflammatory, free radical scavenging, mitochondrial protective and other activities. This review discusses the pharmacology, medicinal chemistry and clinical studies published, especially in China, for danshen and tanshinone preparations. Clinical examinations are evaluated in terms of S. miltiorrhiza preparation, dose, double blinding, control, clinical assessments of outcomes and other parameters. Meta-analyses of S. miltiorrhiza are also discussed.