A plant-derived glucocorticoid receptor modulator with potency to attenuate the side effects of glucocorticoid therapy

Protopanaxadiol derivative: A plant origin of novel selective glucocorticoid receptor modulator with anti-inflammatory effect

Constant efforts have been made to move towards maintaining the positive anti-inflammatory functions of glucocorticoids (GCs) while minimizing side effects. The anti-inflammatory effect of GCs is mainly attributed to the inhibition of major inflammatory pathways such as NF-κB through GR transrepression, while its side effects are mainly mediated by transactivation. Here, we investigated the selective glucocorticoid receptor modulator (SGRM)-like properties of a plant-derived compound. In this study, glucocorticoid receptor (GR)-mediated alleviation of inflammation by SP-8 was investigated by a combination of in vitro, in silico, and in vivo approaches. Molecular docking and cellular thermal shift assay suggested that SP-8 bound stably to the active site of GR via hydrogen bonding and hydrophobic interactions. SP-8 activated GR, induced GR nuclear translocation, and inhibited NF-κB pathway activation. Furthermore, SP-8 did not up-regulate the gene and protein expression of PEPCK and TAT in HepG2 cells, and it did not induce fat deposition like GC and has little effect on bone metabolism. Interestingly, SP-8 upregulated GR protein expression and did not cause GR phosphorylation at Ser211 in RAW264.7 cells. This work proved that SP-8 dissociated characteristics of transrepression and transactivation can be separated. In addition, the in vitro and in vivo anti-inflammatory effects of SP-8 were confirmed in LPS-induced RAW 264.7 cells and in a mouse model of DSS-induced ulcerative colitis, respectively. In conclusion, SP-8 might serve as a potential SGRM and might hold great potential for therapeutic use in inflammatory diseases.

Natural product pharmacology: the British Journal of Pharmacology perspective

Natural products (NPs) have long been used as a rich source of bioactive compounds for drug development. Recent technological advancements have revitalised natural products research as evidenced by increased publications in this field. In this editorial review, we highlight key points from the 2020 British Journal of Pharmacology (BJP) practical guide, which outlines standards for natural products research reports, and provide papers published in BJP between years 2020 to 2023 that demonstrate adherence to these guidelines. Looking ahead, we discuss the potential of chemical proteomics approaches to elucidate natural products mechanisms of action and identify therapeutic targets for future research. By fostering innovation, we aim to advance natural products research and contribute to the development of novel therapeutics that will have a significant impact on healthcare.

Excessive glucocorticoids combined with RANKL promote the differentiation of bone marrow macrophages (BMM) into osteoclasts and accelerate the progression of osteoporosis by activating the SYK/SHP2/NF-κB signaling pathway

The primary objective of this study was to explore the extensive implications and complex molecular interactions arising from the confluence of excessive glucocorticoids and RANKL on the differentiation process of BMM into osteoclasts, profoundly impacting osteoporosis development. The methodology encompassed X-ray analysis and HE staining for evaluating bone loss in mice, while immunohistochemical staining was utilized to observe phosphorylated SHP2 (p-SHP2) expression. The assessment of several phosphorylated and total protein expression levels, including NF-κB, SHP2, SYK, JAK2, TAK1, NFATC1, c-fos, and Cathepsin K, was conducted via Western blotting. Additional experiments, involving CCK8 and monoclonal proliferation assays, were undertaken to determine BMM proliferation capacity. Immunofluorescence staining facilitated the quantification of TRAP fluorescence intensity. In vivo analysis revealed that glucocorticoid surplus triggers SHP2 signaling pathway activation, accelerating osteoporosis progression. Western blot results demonstrated that SHP2 inhibition could decrease the expression of specific proteins such as p-NF-κB and p-SHP2, with minimal effects on p-SYK levels. In vitro findings indicated that glucocorticoid and RANKL interaction activates the SHP2 pathway through NF-κB and SYK pathways, enhancing expressions of p-JAK2, p-TAK1, NFATC1, c-fos, and Cathepsin K, thereby promoting BMM to osteoclast transformation. Conclusion: Excessive glucocorticoids and RANKL interaction advance osteoclast differentiation from BMM by activating the SYK/SHP2/NF-κB signaling pathway, expediting osteoporosis progression.

Skin Anti-Inflammatory Potential with Reduced Side Effects of Novel Glucocorticoid Receptor Agonists

Glucocorticoids (GCs) are commonly used in the treatment of inflammatory skin diseases, although the balance between therapeutic benefits and side effects is still crucial in clinical practice. One of the major and well-known adverse effects of topical GCs is cutaneous atrophy, which seems to be related to the activation of the glucorticoid receptor (GR) genomic pathway. Dissociating anti-inflammatory activity from atrophogenicity represents an important goal to achieve, in order to avoid side effects on keratinocytes and fibroblasts, known target cells of GC action. To this end, we evaluated the biological activity and safety profile of two novel chemical compounds, DE.303 and KL.202, developed as non-transcriptionally acting GR ligands. In primary keratinocytes, both compounds demonstrated anti-inflammatory properties inhibiting NF-κB activity, downregulating inflammatory cytokine release and interfering with pivotal signaling pathways involved in the inflammatory process. Of note, these beneficial actions were not associated with GC-related atrophic effects: treatments of primary keratinocytes and fibroblasts with DE.303 and KL.202 did not induce, contrarily to dexamethasone-a known potent GC-alterations in extracellular matrix components and lipid synthesis, thus confirming their safety profile. These data provide the basis for evaluating these compounds as effective alternatives to the currently used GCs in managing inflammatory skin diseases.

Impact of inhaled and intranasal corticosteroids on glucose metabolism and diabetes mellitus: A mini review

Inhaled corticosteroids (ICS) and intranasal corticosteroids (INS) are the mainstays of treatment for chronic respiratory diseases like asthma, chronic obstructive pulmonary disease, and allergic rhinosinusitis. In addition, these localized forms of steroid therapy are generally considered to have fewer systemic side effects compared to long-term oral corticosteroids. However, concern and controversy remain over the impact of ICS and INS on the incidence and control of diabetes mellitus (DM). Given the widespread use of ICS and INS, even small individual effects on DM could lead to large consequences for the global popu-lation. Multiple large observational studies suggest that high dose ICS is associated with increased incident DM and worsened DM control, though the contribution of other risk factors is less certain. In addition, only two studies were done to investigate the association of INS and DM, with both studies demon-strating a short-term association of INS use with hyperglycemia. While more research evaluating the risk of ICS/INS for DM-related adverse events is needed, high doses of ICS/INS should be avoided when possible. The following strategies for ICS/INS dose minimization can be considered: Use of non-pharmacological measures (trigger avoidance, smoking cessation, vaccination to avoid infection), control of comorbid conditions, use of non-ICS-containing medications, inter-mittent rather than regular ICS dosing, and appropriate de-escalation of high ICS doses.